At the present time extensive varieties of pesticides are being used but the demand for organophosphorus pesticide is
increasing globally to control insect. Chlorpyrifos is a broad spectrum, moderately toxic, chlorinated
organophosphate insecticide that is synthetic in origin and is normally ester or thiol derivatives of phosphoric,
phosphonic or phosphoramidic acids. The mode of action involves inhibiting acetyl cholinesterase leading to
accumulation of acetylcholine causing neurotoxicity. It is being transported by circulation far away from site of
application leading to pollution of environment. Due to its persistent in nature, it is not only severely detrimental to
the target pests, but also causes toxicity in non -target organisms including humans. It is thus critically important to
develop methods to eradicate these pollutants from the environment. Lately, research activities in this area have
demonstrated that microorganisms are potential tool in decaying chlorpyrifos into less harmful and non -toxic
metabolites through a process known as bioremediation. This article therefore aims at giving an overview of the
present status of research and future prospects in bioremediation of chlorpyrifos
Catalogue of community medicine spottersRizwan S A
This document provides a catalogue of items from the Department of Community Medicine at Velammal Medical College Hospital & Research Institute. It includes descriptions of various disinfectants, pesticides, vaccines, nutrition items, and public health equipment. Disinfectants described include savlon, bleaching powder, malathion, and abate. Items for measuring nutrition include an analytical balance, lactometer, and fat extraction apparatus. Vaccines mentioned include MMR, polio, and typhoid vaccines. The document provides information on the uses, properties, and application of these various public health and medical items.
Commonly used Insecticides and Pesticides KULDEEP VYAS
Pesticides include insecticides, herbicides and fungicides. There are several thousand different types in use and almost all of them are possible causes of water pollution. For example, DDT, malathion, parathion, delthametrine and others have been sprayed in the environment for long periods of time for the control of disease vectors such as mosquitoes, and to control the growth of weeds and other pests.
This document discusses pesticide residues in food. It begins by defining pesticides and explaining how residues can occur in foods when pesticides are used during agricultural production. It notes that processing foods can help reduce residues. It then discusses groups vulnerable to pesticide effects like children. The document outlines pesticide risk assessment and various health effects of pesticide exposure. It concludes by discussing approaches for preventing and controlling pesticide residues like consumer education, legislation, research into alternatives, and promotion of integrated pest management.
Seminar on pesticide analysis by prakashprakash64742
The document summarizes a seminar on pesticide analysis presented by Prakash Gupta. It discusses the effects of pests on food, the use of pesticides in agriculture, and various types of pesticides. It also outlines the benefits of pesticide use, such as increasing food production and controlling diseases, but also describes problems with pesticides like their impacts on non-target organisms, persistence in the environment, and potential to cause health issues. The seminar provided an overview of pesticide regulation through acts like FIFRA and FQPA.
Pesticides classification and maximum residue limits in foodsherif Taha
This presentation describes main pesticide classification and illustrate how to obtain MRL for pesticide residue in EU, Codex alimentarius, USA, and Japan
insecticide pollution, persistance and problems associated with agricultureSafeena Majeed
The document discusses the negative environmental impacts of pesticide use in agriculture. It notes that pesticides can persist in soil and water for long periods of time, killing beneficial organisms and contaminating ecosystems. Their overuse has led to issues like pest resurgence and the development of resistance. The document also examines the health hazards of pesticide exposure through soil, water and air to humans and other organisms. Long-term effects on farmers and communities have included increased rates of cancer, neurological and respiratory diseases. Proper regulation and alternative methods of pest control are needed to reduce these risks.
The document summarizes a study that tested for the presence of nitrogen-containing pesticides and insecticides in various fruits and vegetables like apples, grapes, brinjal, and tomatoes. Samples of the fruits and vegetables were crushed and extracted with alcohol. The extracts were then tested using Lassigne's test, which involves fusing the extract with sodium and testing the filtrate for the presence of cyanide ions, indicating the presence of nitrogen and thus pesticides. All fruit and vegetable samples showed positive results, suggesting the presence of nitrogenous pesticides in all tested foods. The study demonstrates a method for detecting pesticide residues in foods.
Catalogue of community medicine spottersRizwan S A
This document provides a catalogue of items from the Department of Community Medicine at Velammal Medical College Hospital & Research Institute. It includes descriptions of various disinfectants, pesticides, vaccines, nutrition items, and public health equipment. Disinfectants described include savlon, bleaching powder, malathion, and abate. Items for measuring nutrition include an analytical balance, lactometer, and fat extraction apparatus. Vaccines mentioned include MMR, polio, and typhoid vaccines. The document provides information on the uses, properties, and application of these various public health and medical items.
Commonly used Insecticides and Pesticides KULDEEP VYAS
Pesticides include insecticides, herbicides and fungicides. There are several thousand different types in use and almost all of them are possible causes of water pollution. For example, DDT, malathion, parathion, delthametrine and others have been sprayed in the environment for long periods of time for the control of disease vectors such as mosquitoes, and to control the growth of weeds and other pests.
This document discusses pesticide residues in food. It begins by defining pesticides and explaining how residues can occur in foods when pesticides are used during agricultural production. It notes that processing foods can help reduce residues. It then discusses groups vulnerable to pesticide effects like children. The document outlines pesticide risk assessment and various health effects of pesticide exposure. It concludes by discussing approaches for preventing and controlling pesticide residues like consumer education, legislation, research into alternatives, and promotion of integrated pest management.
Seminar on pesticide analysis by prakashprakash64742
The document summarizes a seminar on pesticide analysis presented by Prakash Gupta. It discusses the effects of pests on food, the use of pesticides in agriculture, and various types of pesticides. It also outlines the benefits of pesticide use, such as increasing food production and controlling diseases, but also describes problems with pesticides like their impacts on non-target organisms, persistence in the environment, and potential to cause health issues. The seminar provided an overview of pesticide regulation through acts like FIFRA and FQPA.
Pesticides classification and maximum residue limits in foodsherif Taha
This presentation describes main pesticide classification and illustrate how to obtain MRL for pesticide residue in EU, Codex alimentarius, USA, and Japan
insecticide pollution, persistance and problems associated with agricultureSafeena Majeed
The document discusses the negative environmental impacts of pesticide use in agriculture. It notes that pesticides can persist in soil and water for long periods of time, killing beneficial organisms and contaminating ecosystems. Their overuse has led to issues like pest resurgence and the development of resistance. The document also examines the health hazards of pesticide exposure through soil, water and air to humans and other organisms. Long-term effects on farmers and communities have included increased rates of cancer, neurological and respiratory diseases. Proper regulation and alternative methods of pest control are needed to reduce these risks.
The document summarizes a study that tested for the presence of nitrogen-containing pesticides and insecticides in various fruits and vegetables like apples, grapes, brinjal, and tomatoes. Samples of the fruits and vegetables were crushed and extracted with alcohol. The extracts were then tested using Lassigne's test, which involves fusing the extract with sodium and testing the filtrate for the presence of cyanide ions, indicating the presence of nitrogen and thus pesticides. All fruit and vegetable samples showed positive results, suggesting the presence of nitrogenous pesticides in all tested foods. The study demonstrates a method for detecting pesticide residues in foods.
Fruits and vegetables are highly nutritious but also highly perishable, leading them to often be contaminated with toxic pesticides. Testing found that 98% of apples and over 95% of celery contained at least one pesticide residue. Common fruits and vegetables like strawberries, spinach, and grapes frequently test positive for pesticides. Pesticides are designed to kill and are generally not good for human consumption. Reducing exposure by peeling produce and washing hands and surfaces thoroughly can help lower health risks from pesticide residues.
Pesticides are substances used to kill pests like insects, weeds, rodents, and fungi that damage crops or transmit diseases. They work by inhibiting the metabolic processes of pests. Common types include insecticides, herbicides, rodenticides, and fungicides. Integrated Pest Management is an approach that uses targeted pest control methods like biological and mechanical controls instead of relying solely on chemical pesticides. Choosing the right pesticide depends on the type of pest and habitat. Some natural pesticides come from plants like tobacco, pyrethrum, and derris elliptica.
The document discusses the environmental impacts of pesticides, how pesticides can contaminate soil and water sources like groundwater, and the health effects pesticides can have on humans and non-target organisms through routes of exposure like skin contact, inhalation, and ingestion. It also provides information on emergency responses to pesticide exposure, like first aid measures and contacting poison control centers, as well as the risks of heat stress when applying pesticides in hot conditions. The goals of responsible pesticide use are to achieve effective pest control while minimizing risks to the environment.
This document discusses pesticides and insecticides used in agriculture. It defines pesticides as substances that kill pests and insecticides as a subclass of pesticides that kill insects. It describes how pesticides are commonly used by farmers and homeowners and provides a brief history of pesticide use. The document outlines different types of insecticides including organochlorines, organophosphates, and carbamates. It discusses the impacts of pesticide use on the environment, economy, and human health.
This document defines persistent pollutants as toxic chemicals that remain in the environment for long periods without breaking down, accumulate in animals through the food chain, and are widespread. It discusses specific persistent organic pollutants like DDT, PCBs, dioxins, and mercury that were widely used but are now regulated or banned due to health effects. The document also outlines integrated pest management as a more sustainable approach than using persistent pesticides.
Any substance or mixture of substances, intended for preventing, destroying, or
mitigating any pest, or intended for use as a plant growth regulator, defoliant or
desiccant.
Pesticides play a sensitive role in food systems. we can see a visible parallel correlation between higher productivity, high chemical input use and environmental degradation and human health effects. There is need to be aware of pesticides pollution, its impact and make policies for its reduction.
Organochlorine pesticides are organic compounds containing chlorine that were the first synthetic pesticides widely used in agriculture and public health. They act as nervous system disruptors in insects, causing convulsions and paralysis. Examples include DDT, lindane, and endosulfan. Organochlorines are highly persistent, building up in tissues and food chains. They were commonly used to control insects before some were banned due to environmental impacts.
This presentation discusses agrochemicals and pesticides. It defines agrochemicals as chemical products used in agriculture, and pesticides as substances used to eradicate pests. Pesticides are classified according to their mode of action and chemicals. Insecticides are substances used to kill insects, and are classified as systemic or contact based on activity, and inorganic or organic based on chemical nature. The presentation notes the first use of synthetic pesticides in 1940 and their environmental impacts like air, water, and soil pollution.
Pesticides have widespread negative effects on ecosystems. Over 98% of insecticides and 95% of herbicides do not reach their intended target, and instead contaminate air, water, soil and non-target species. Pesticide use reduces biodiversity and threatens endangered species. Pesticides bioaccumulate up the food chain and can cause poisoning in livestock, wildlife and pets. While pesticides are intended to control pests, they also have unintended consequences across entire ecosystems. Alternative approaches like manual removal of weeds, using pest traps and lures, and supporting natural biocontrol agents can help control pests while avoiding harmful pesticides.
Pesticides use in agriculture: benefits, risks and safetykrishgupta17
This document discusses pesticides, including their history, types, uses, and risks. It notes that pesticides have increased agricultural production but also pose environmental and health risks. The main types of pesticides are insecticides, fungicides, herbicides, and rodenticides. Risks include negative effects on humans, water and soil pollution, resistance in pests, and impacts on non-target species and pollinators. Proper use and disposal of pesticides can help reduce risks to human and environmental health.
Pesticides have been linked to a number of health problems, including neurologic and endocrine (hormone) system disorders, birth defects, cancer, and other diseases.
This document discusses the environmental concerns of pesticides. It outlines how pesticides can affect human health, target organisms, non-target organisms, soil environments, and water and air ecosystems. Pesticides can cause health issues for people with direct and indirect exposure through various routes. They can also lead to pest resistance, resurgence, and effects on soil microbes, earthworms, pollinators, and predators. When pesticides enter water and air, they negatively impact fish, birds and other organisms. The document provides examples and details for many of these topics over 22 sections.
The document discusses the current regulations for pesticide use in farming and whether they are sufficient for healthy living. It provides information on what pesticides are, the EPA regulations, types of pesticides and their effects, advantages and disadvantages of pesticide use, potential health effects, benefits of organic foods, and advances in technology that could reduce pesticide use. While pesticides improve food production and quality of life, the EPA approval process is slow and pesticides can damage the environment and health, especially for sensitive groups. More research into alternatives is still needed to establish effective regulations that protect both public health and agriculture.
Pesticides are chemicals designed to kill pests like weeds, insects, and fungi. They can cause acute poisoning, delayed illnesses, and allergic reactions in humans exposed through various means like ingestion, inhalation, eye or skin contact. Symptoms range from skin/eye irritation to excessive sweating or difficulty breathing. Exposure is prevented through proper storage, use of protective equipment, integrated pest management, and community education. First aid involves washing exposed areas, inducing vomiting only if instructed, and getting medical help. While pesticides boost agriculture, improper use without training harms both human and environmental health.
This document defines pesticides and describes different types of pests including animal pests like rodents and insects, and plant pests like weeds and microorganisms. It discusses how pesticides work by inhibiting metabolic processes and outlines their mechanism of action, potency, onset, and dose. Common pesticide types include insecticides, herbicides, fungicides, and rodenticides. The document also covers pesticide choice based on pest type and habitat, as well as methods of controlling pests including mechanical, biological, environmental, agricultural, and chemical methods. Integrated Pest Management is discussed as an alternative approach.
The document discusses understanding pesticides and provides information on key parts of a pesticide label. It defines what a pesticide is, outlines which federal agency regulates them, and describes common pesticide formulations and terminology. It also discusses toxicity and hazards of pesticides, explaining how they are determined. The label sections are then outlined, including the brand name, signal words, directions for use, precautions, active ingredients, and contact information. Common label violations are also noted.
This science exhibition presentation summarizes the negative effects of chemical pesticides on the environment. It discusses how pesticides can contaminate air, water, and soil through drift, runoff, and leaching. This pollution impacts ecosystems and public health. Pesticides also reduce biodiversity in soil, harm pollinators, and can cause pests to develop resistance over time. The presentation advocates for alternative pest control methods like integrated pest management that are more environmentally friendly.
Bioremediation of Chlorpyrifos Contaminated Soil by MicroorganismIJEAB
India is agricultural based country where 70% of the population survives on it. In order to increase the production of field various pesticides are used. Chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate) is an organophosphate pesticide which is widely used as insecticide for crop protection. But due to its persistent nature into the environment, it is leading to various hazards including neurotoxic effects, cardiovascular diseases and respiratory diseases. Bioremediation is a technology to eliminate chlorpyrifos efficiently from the environment. In bioremediation of chlorpyrifos the potential degradative microorganisms possess opd (organophosphate degrading) gene which hydrolyses the chlorpyrifos and utilizes it as a sole carbon source.Thus the present review discusses about how through bioremediation the pesticide chlorpyrifos can be degraded using potential soil microorganisms.
QUINALPHOS INDUCED BIOCHEMICAL AND PATHOPHYSIOLOGICAL CHANGES IN FRESHWATER E...Sameer Chebbi
This document discusses a study on the biochemical and pathophysiological changes in the freshwater fish Cyprinus carpio exposed to the organophosphate pesticide quinalphos. The study aims to understand the toxic effects of lethal and sublethal concentrations of quinalphos on C. carpio over different exposure periods. Biochemical parameters like proteins, oxidative stress markers, acetylcholinesterase activity, ions, and ATPases will be analyzed in the gills, kidney, and liver tissues of exposed fish. Histopathological changes and accumulation of the pesticide will also be examined in these tissues. The results will provide insights into the toxic impacts of quinalphos exposure on C. carpio at biochemical
Fruits and vegetables are highly nutritious but also highly perishable, leading them to often be contaminated with toxic pesticides. Testing found that 98% of apples and over 95% of celery contained at least one pesticide residue. Common fruits and vegetables like strawberries, spinach, and grapes frequently test positive for pesticides. Pesticides are designed to kill and are generally not good for human consumption. Reducing exposure by peeling produce and washing hands and surfaces thoroughly can help lower health risks from pesticide residues.
Pesticides are substances used to kill pests like insects, weeds, rodents, and fungi that damage crops or transmit diseases. They work by inhibiting the metabolic processes of pests. Common types include insecticides, herbicides, rodenticides, and fungicides. Integrated Pest Management is an approach that uses targeted pest control methods like biological and mechanical controls instead of relying solely on chemical pesticides. Choosing the right pesticide depends on the type of pest and habitat. Some natural pesticides come from plants like tobacco, pyrethrum, and derris elliptica.
The document discusses the environmental impacts of pesticides, how pesticides can contaminate soil and water sources like groundwater, and the health effects pesticides can have on humans and non-target organisms through routes of exposure like skin contact, inhalation, and ingestion. It also provides information on emergency responses to pesticide exposure, like first aid measures and contacting poison control centers, as well as the risks of heat stress when applying pesticides in hot conditions. The goals of responsible pesticide use are to achieve effective pest control while minimizing risks to the environment.
This document discusses pesticides and insecticides used in agriculture. It defines pesticides as substances that kill pests and insecticides as a subclass of pesticides that kill insects. It describes how pesticides are commonly used by farmers and homeowners and provides a brief history of pesticide use. The document outlines different types of insecticides including organochlorines, organophosphates, and carbamates. It discusses the impacts of pesticide use on the environment, economy, and human health.
This document defines persistent pollutants as toxic chemicals that remain in the environment for long periods without breaking down, accumulate in animals through the food chain, and are widespread. It discusses specific persistent organic pollutants like DDT, PCBs, dioxins, and mercury that were widely used but are now regulated or banned due to health effects. The document also outlines integrated pest management as a more sustainable approach than using persistent pesticides.
Any substance or mixture of substances, intended for preventing, destroying, or
mitigating any pest, or intended for use as a plant growth regulator, defoliant or
desiccant.
Pesticides play a sensitive role in food systems. we can see a visible parallel correlation between higher productivity, high chemical input use and environmental degradation and human health effects. There is need to be aware of pesticides pollution, its impact and make policies for its reduction.
Organochlorine pesticides are organic compounds containing chlorine that were the first synthetic pesticides widely used in agriculture and public health. They act as nervous system disruptors in insects, causing convulsions and paralysis. Examples include DDT, lindane, and endosulfan. Organochlorines are highly persistent, building up in tissues and food chains. They were commonly used to control insects before some were banned due to environmental impacts.
This presentation discusses agrochemicals and pesticides. It defines agrochemicals as chemical products used in agriculture, and pesticides as substances used to eradicate pests. Pesticides are classified according to their mode of action and chemicals. Insecticides are substances used to kill insects, and are classified as systemic or contact based on activity, and inorganic or organic based on chemical nature. The presentation notes the first use of synthetic pesticides in 1940 and their environmental impacts like air, water, and soil pollution.
Pesticides have widespread negative effects on ecosystems. Over 98% of insecticides and 95% of herbicides do not reach their intended target, and instead contaminate air, water, soil and non-target species. Pesticide use reduces biodiversity and threatens endangered species. Pesticides bioaccumulate up the food chain and can cause poisoning in livestock, wildlife and pets. While pesticides are intended to control pests, they also have unintended consequences across entire ecosystems. Alternative approaches like manual removal of weeds, using pest traps and lures, and supporting natural biocontrol agents can help control pests while avoiding harmful pesticides.
Pesticides use in agriculture: benefits, risks and safetykrishgupta17
This document discusses pesticides, including their history, types, uses, and risks. It notes that pesticides have increased agricultural production but also pose environmental and health risks. The main types of pesticides are insecticides, fungicides, herbicides, and rodenticides. Risks include negative effects on humans, water and soil pollution, resistance in pests, and impacts on non-target species and pollinators. Proper use and disposal of pesticides can help reduce risks to human and environmental health.
Pesticides have been linked to a number of health problems, including neurologic and endocrine (hormone) system disorders, birth defects, cancer, and other diseases.
This document discusses the environmental concerns of pesticides. It outlines how pesticides can affect human health, target organisms, non-target organisms, soil environments, and water and air ecosystems. Pesticides can cause health issues for people with direct and indirect exposure through various routes. They can also lead to pest resistance, resurgence, and effects on soil microbes, earthworms, pollinators, and predators. When pesticides enter water and air, they negatively impact fish, birds and other organisms. The document provides examples and details for many of these topics over 22 sections.
The document discusses the current regulations for pesticide use in farming and whether they are sufficient for healthy living. It provides information on what pesticides are, the EPA regulations, types of pesticides and their effects, advantages and disadvantages of pesticide use, potential health effects, benefits of organic foods, and advances in technology that could reduce pesticide use. While pesticides improve food production and quality of life, the EPA approval process is slow and pesticides can damage the environment and health, especially for sensitive groups. More research into alternatives is still needed to establish effective regulations that protect both public health and agriculture.
Pesticides are chemicals designed to kill pests like weeds, insects, and fungi. They can cause acute poisoning, delayed illnesses, and allergic reactions in humans exposed through various means like ingestion, inhalation, eye or skin contact. Symptoms range from skin/eye irritation to excessive sweating or difficulty breathing. Exposure is prevented through proper storage, use of protective equipment, integrated pest management, and community education. First aid involves washing exposed areas, inducing vomiting only if instructed, and getting medical help. While pesticides boost agriculture, improper use without training harms both human and environmental health.
This document defines pesticides and describes different types of pests including animal pests like rodents and insects, and plant pests like weeds and microorganisms. It discusses how pesticides work by inhibiting metabolic processes and outlines their mechanism of action, potency, onset, and dose. Common pesticide types include insecticides, herbicides, fungicides, and rodenticides. The document also covers pesticide choice based on pest type and habitat, as well as methods of controlling pests including mechanical, biological, environmental, agricultural, and chemical methods. Integrated Pest Management is discussed as an alternative approach.
The document discusses understanding pesticides and provides information on key parts of a pesticide label. It defines what a pesticide is, outlines which federal agency regulates them, and describes common pesticide formulations and terminology. It also discusses toxicity and hazards of pesticides, explaining how they are determined. The label sections are then outlined, including the brand name, signal words, directions for use, precautions, active ingredients, and contact information. Common label violations are also noted.
This science exhibition presentation summarizes the negative effects of chemical pesticides on the environment. It discusses how pesticides can contaminate air, water, and soil through drift, runoff, and leaching. This pollution impacts ecosystems and public health. Pesticides also reduce biodiversity in soil, harm pollinators, and can cause pests to develop resistance over time. The presentation advocates for alternative pest control methods like integrated pest management that are more environmentally friendly.
Bioremediation of Chlorpyrifos Contaminated Soil by MicroorganismIJEAB
India is agricultural based country where 70% of the population survives on it. In order to increase the production of field various pesticides are used. Chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate) is an organophosphate pesticide which is widely used as insecticide for crop protection. But due to its persistent nature into the environment, it is leading to various hazards including neurotoxic effects, cardiovascular diseases and respiratory diseases. Bioremediation is a technology to eliminate chlorpyrifos efficiently from the environment. In bioremediation of chlorpyrifos the potential degradative microorganisms possess opd (organophosphate degrading) gene which hydrolyses the chlorpyrifos and utilizes it as a sole carbon source.Thus the present review discusses about how through bioremediation the pesticide chlorpyrifos can be degraded using potential soil microorganisms.
QUINALPHOS INDUCED BIOCHEMICAL AND PATHOPHYSIOLOGICAL CHANGES IN FRESHWATER E...Sameer Chebbi
This document discusses a study on the biochemical and pathophysiological changes in the freshwater fish Cyprinus carpio exposed to the organophosphate pesticide quinalphos. The study aims to understand the toxic effects of lethal and sublethal concentrations of quinalphos on C. carpio over different exposure periods. Biochemical parameters like proteins, oxidative stress markers, acetylcholinesterase activity, ions, and ATPases will be analyzed in the gills, kidney, and liver tissues of exposed fish. Histopathological changes and accumulation of the pesticide will also be examined in these tissues. The results will provide insights into the toxic impacts of quinalphos exposure on C. carpio at biochemical
IOSR Journal of Pharmacy (IOSRPHR), www.iosrphr.org, call for paper, research...iosrphr_editor
IOSR Journal of Pharmacy (IOSRPHR), www.iosrphr.org, call for paper, research paper publishing, where to publish research paper, journal publishing, how to publish research paper, Call for research paper, international journal, publishing a paper, call for paper 2012, journal of pharmacy, how to get a research paper published, publishing a paper, publishing of journal, research and review articles, Pharmacy journal, International Journal of Pharmacy, hard copy of journal, hard copy of certificates, online Submission, where to publish research paper, journal publishing, international journal, publishing a paper
GRAD STUDENT SYMPOSIUM WWTP mass balance poster Sam 3-3-15 30x45Sam Supowit
- Conventional wastewater treatment is not efficient at removing fiproles like fipronil, with total fiprole levels remaining similar between influent and effluent.
- Fipronil is reduced by about 25% during treatment, while its metabolite fipronil sulfone forms, likely in aerobic reactors.
- Total fiprole levels re-entering the environment from wastewater treatment effluent are toxicologically relevant and may impact aquatic life.
This document provides definitions and information about pesticides. It begins with defining pesticides as substances intended to prevent, destroy or mitigate pests. It then discusses the history of pesticide use dating back to ancient civilizations, and provides examples of early pest control methods. The document categorizes common types of pesticides and discusses their classification, including organochlorines, organophosphates, carbamates, and pyrethroids. It also covers toxicity measures such as LD50, LC50 and MLD values.
This document discusses and compares organic agriculture and conventional agriculture that uses synthetic pesticides. It notes that while pesticides increase crop yields, there are also concerns about their impacts on human health, animal health, and the environment. The document then provides details on the history and types of pesticides used in agriculture, such as organochlorines and organophosphates. It also discusses the standards and regulations around organic certification. While organic farming avoids synthetic pesticides, it still uses natural pesticides that can also be toxic. Overall, the document examines some of the debates and misconceptions around organic versus conventional methods.
1. The study isolated 32 bacterial strains from chlorpyrifos contaminated soil that were able to degrade chlorpyrifos as the sole carbon source.
2. Four strains - SGB2, SWLC1, SWLC2, and SWLH2 - were able to degrade up to 92% of 100 mg/L chlorpyrifos within 18 days under shaking conditions at 30°C and neutral pH.
3. Analysis showed the biodegradation was directly correlated to bacterial growth, indicating it was a growth-linked process. 16S rRNA gene sequencing identified the strains as Enterobacter spp. (SGB2, SWLC1, SWLC2) and Agrobacterium (SWLH
This document discusses the health hazards of fungicide residues. It begins by defining fungicides and fungicide residues. It then discusses how pesticide residues occur in agriculture and related terms like persistence and deposit. It outlines some maximum residue limits set by India and the Codex Alimentarius. It details several toxic effects of pesticide residues on human health like neuronal damage, long-term neuropsychiatric disorders, persistent memory and cognitive deficits, psychomotor performance deficits, oxidative stress, cancer development, and reproductive disorders.
ABSTRACT- Mosquito-borne diseases have intruded the globe since immemorial time. The present scenario for
commanding the mosquitoes is aimed at application of target and stage-specific, cost-effective and biodegradable
phytoproducts. Plant extracts are safer for non-target organisms including man. Plant based formulations would be more
feasible environmental products with proven potential as insecticide. Therefore, in the present study of larvicidal
activity of biologically active compound Apigenin extracted from leaf of Jatropha gossypifolia against the filarial
vector, Culex quinquefasciatus was studied. Standard WHO protocols with minor modifications was adopted for the
larvicidal bioassay. The active compound Apigenin extracted through ethyl alcohol solvent from the leaf of Jatropha
gossypifolia plant of family Euphorbiaceae was administered for 24h or 96h to the larvae of Culex quinquefasciatus.
Exposure of larvae over 24h to sub-lethal doses (40% and 80% of LC50) of apigenin, significantly (P<0.05) altered the
level of total protein, total free amino acid, glycogen and activity of enzymes acetyl cholinesterase, acid and alkaline
phosphatase activity in whole body tissue of Culex quinquefasciatus larvae. The alterations in all these biochemical
parameters were significantly (P<0.05) time and dose dependent.
Key-words- Jatropha gossypifolia, Euphorbiaceae, Culex quinquefasciatus, biochemical effects, Wuchereria bancrofti
The document summarizes a study on the toxicity effects of the pesticide Monocrotophos 36% EC on the hematology of the fish Labeo rohita. The study found that exposure to sublethal concentrations of Monocrotophos resulted in decreased red blood cell count, hemoglobin content, and total erythrocytes over time. Meanwhile, white blood cell count increased with increasing exposure time, indicating the pesticide stimulated white blood cell production. Overall, the results show Monocrotophos exposure caused anemia and physiological stress responses in the hematological parameters measured in L. rohita.
The document summarizes the findings of a study on organochlorine pesticide concentrations in sediment samples from 12 sites along the River Yamuna in Agra, India. High levels of pesticides were found, particularly HCH isomers, which can be attributed to agricultural and public health uses of pesticides. Alpha-HCH and gamma-HCH were generally found at higher concentrations than other isomers. The distribution of pesticides was uneven across sampling sites and did not follow a single pattern, likely due to differences in pesticide and sediment properties as well as transportation and transformation processes. Pesticide concentrations pose risks to environmental and human health.
Describes Various aspects of pharmaceutical products affecting the environment.
Effects of Environmental pollution by Drugs on Aquatic systems and Humans.
Examples of drugs on various environmental effects are given.
Impact of pesticide on ecosystem and human health.pptxHemchandraJha3
The document discusses the impacts of pesticide usage on ecosystems and human health. It notes that pesticide residues can persist in the environment and pose threats. Pesticides can enter the environment through various pathways like drift during application, runoff, and leaching into groundwater. Long-term pesticide exposure is linked to negative effects like damage to beneficial soil organisms, water pollution, air pollution, and increased cancer risks for humans. The widespread use of chemical pesticides has significant effects on both environmental and human health worldwide.
Abstract— After the II Word War, the chemical based industrial revolution generated a wide and global contamination due to the release in the environment of thousand of compounds without an adequate knowledge of their environmental biotransformation and their toxic effect on the living matter. Recently, it has been found that several of these compounds and/or their relative by-products are persistent environmental contaminants associated with undesirable long-term effects. At present many questions have to be clarified with particular reference to lipophilic polyhalogenated compounds, such as polychloro-dibenzo-dioxins (PCDD), polychloro-dibenzo-furans (PCDF) and polychloro-biphenyls (PCB). These compounds accumulate up the food chain and humans can reach relative high concentration in their body with a consequent risk for health. In this paper we discuss the some basic features of both biological and toxicological aspects related to the dioxins exposure.
Triclosan Persistence in Environment and Its Potential Toxic Effects on AlgaeAJASTJournal
1) The document examines the persistence of triclosan in the environment and its potential toxic effects on algae. It finds that triclosan decreases algae growth and chlorophyll a concentration in a dose-dependent manner.
2) The study exposed the microalga Nannochloropsis sp. to different concentrations of triclosan from 10-50 ppm. It observed decreased algae population, changes in color, and decreased chlorophyll a levels as the triclosan concentration increased.
3) Growth curves showed triclosan treatment reduced the exponential phase and led to an earlier decline phase compared to the control. Conductivity also increased with decreased chlorophyll a and phytop
Toxicity and Effect of Cypermethrin onTotal Protein and Nucleic Acid Content ...Agriculture Journal IJOEAR
— Effect of cypermethrin (25%EC) on total protein and nucleic acid content in different tissues of Cirrhinus mrigala was assessed by static renewal bioassay, using different sub-lethal concentrations (5, 10, 15 and 20% of 96h LC 50) for 5, 10 and 15 days duration. There was a gradual decrease in protein content in all the tissues under sub-lethal concentrations at all exposure periods with maximum percentage of depletion (45.26%) in muscle and minimum (35.12%) in kidney at 15 days and at 20% 96hLC50. DNA and RNA contents were not altered much by cypermethrin at 5 th day which later gradually decreased with increased exposure period. Decrement in DNA content is less in muscle when compared to the other tissues. Maximum percentage of depletion in DNA was (17.17%) in liver and minimum (13.94%) in muscle at 15 days and at 20% 96hLC50. RNA content decreased significantly in liver (29.90%), muscle (25.53%), brain (23.38%), kidney (21.82%) and gill (20.34%). This decrease was comparatively higher at 15 days and at 20% 96hLC50. Influence of cypermethrin was found to be time and exposure dependent for both the nucleic acids in the aquaculture practices used edible fish.
Pesticides can persist in the environment for long periods and accumulate in living organisms. They are linked to serious health effects in humans and other species. Pesticides enter aquatic environments through various pathways like agricultural use, dumping of waste, and atmospheric deposition. Their fate depends on factors like solubility, adsorption, and bioaccumulation. Pesticides can have ecological impacts like death, reproductive inhibition, immune suppression, and physiological effects in organisms as well as human health impacts through ingestion, inhalation, and skin contact. Persistent organic pollutants are resistant to degradation, can undergo long-range transport and bioaccumulation, and have impacts on health and environment.
Pesticides play a vital role in agricultural production by controlling pests and increasing crop yields, though they can also negatively impact the environment if not properly disposed of. The document discusses methods for disposing of and treating pesticide waste, including land cultivation, which uses soil microbes to break down pesticides over time, and composting, where microbes decompose biodegradable pesticide compounds. The conclusion evaluates different disposal and treatment methods based on criteria like detoxification ability and cost to determine suitable options for on-farm use.
ABSTRACT- Tobacco caterpillar, Spodoptera litura (Fabricius) is a widely distributed pest in South-East Asia, feeding on 63 plant species belonging to 22 families. It is a serious pest of soybean, pulses oilseeds, cotton and vegetables. In an outbreak phase, this insect can completely defoliate large area of crops causing reduction in yield. Heavy use of synthetic organic insecticides to control this pest resulted in the development of resistance against insecticides of different groups. Although a variety of agrochemicals are used for growing crops, little is known about their direct or indirect effects on nontarget organisms including insect pests. Therefore, alternative control measures have been searched out for this noxious pest. By adopting probable and advanced management practices this important pest can be managed. Key-words- Spodoptera litura, Bioassay, agrochemicals, Growth and development, Polyphagous pest
This research article studied the effects of gamma radiation on total phenolic content, flavonoids, and antioxidant activity in dried Pleurotus ostreatus mushrooms stored in different packaging materials. Dried mushrooms were exposed to gamma radiation doses from 0 to 2 kGy and stored for 1 month. Extracts from the mushrooms were analyzed for total phenolic content, flavonoids, and antioxidant activity. Statistical differences were found between the extracts and radiation doses. A significant positive correlation was observed between total phenolic content and antioxidant activity. The results suggest that P. ostreatus mushrooms can be a promising source of natural antioxidants and low dose gamma radiation may help improve quality, shelf-life and nutrient preservation of mushrooms.
Similar to Biodegradation of Organophosphorous Pesticide: Chlorpyrifos (20)
Scientific Management of Equipment in Medical Innovation LaboratoryScientific Review SR
Aim; To solve the problem of innovation laboratory instrument management and improve laboratory management level. Method; It is necessary to do an excellent job in managing innovative laboratory equipment by improving the equipment management system, functional division management, appointment registration, and strengthening the construction of management teams to guarantee the cultivation of innovation and entrepreneurship capabilities of undergraduates. Results; The number of innovative experimental projects approved and the number of project groups that the laboratory can accept at the same time was increased significantly. The utilization rate of laboratory equipment has increased, and the vacancy rate has decreased. Conclusion; Excellent instrument management can significantly improve the efficiency of scientific research in the innovation laboratory.
Internationalization and Sustainable Operations: A Broad Investigation of Chi...Scientific Review SR
We investigate if internationalization behaviors encourage sustainable operations of China’s manufacturing firms due to their substantial impact on climate change and special governance modes, and organize a heterogeneity test to clarify what kind of internationalization behaviors can robustly influence such operations. We find that firms with abundant assets and heavy-polluting feature are more committed to sustainable operations. Getting close to international sustainability standards, international auditing standards, and international business all improve sustainable operations. Heterogeneity test further shows that compared with international standards, the positive impact of international business on sustainable operation lacks a robustness, which responds to an argument that for one country, international business acts as a double-edged sword. Overall, this paper reveals internationalization as a key indicator significantly influencing economic, ecological, and social spheres in manufacturing sectors of emerging markets, and complying with well-accepted international standards can be significantly embodied in a more optimistic sustainable operations. However, how to deal with international business in a right manner is a research highlight worthy of ongoing discussion. We focus on different types of internationalization behaviors, and this indicator can theoretically inspire future study to dialectically evaluate the role of internationalization in addressing sustainability problems in emerging markets’ pillar industries.
Mechanical Engineering in Ancient Egypt, Part 92: Tomb Inscription During the...Scientific Review SR
This document discusses ancient Egyptian tomb inscriptions from the Old Kingdom period, specifically the Third through Fifth Dynasties. It provides several examples of reliefs and scenes from tombs that contain hieroglyphic inscriptions, including a relief of a dentist from the Third Dynasty, a hunting scene from a Fourth Dynasty tomb with an inscription above, and a colorful scene from a Fifth Dynasty tomb with a descriptive text in four columns above the images. The document examines the development of tomb inscriptions during this early period in ancient Egypt and highlights the important role they played in documenting the tomb owners' lives and achievements.
Usability Engineering, Human Computer Interaction and Allied Sciences: With R...Scientific Review SR
Human Computer Interaction is actually responsible for the designing of the computing technologies keeping in mind the aspects of Interaction. Some of the fields viz. Man-Machine Interaction (MMI), User Experience Designing, User Experience Design, Human Centered Designing etc and importantly all these systems and technologies are dedicated to the designing of interface of various tools and systems such as computers, laptops, electronic systems, smart phones etc. Information Technology field is growing rapidly and there are various technologies are increasing viz. Big Data Management, Cloud Computing, Green Computing, Data Science, Internet of Things (IoT), HCI, Usability Engineering etc. Usability Engineering is gaining as a field of study as well and dedicated in creation of the higher usability and user friendliness of the electronic tools and products. In this field few aspects and technologies are most important and emerging viz. Human cognition, behavioral Research Methods, Quantitative techniques etc for the development of usability systems. Designing, implementation, usability even in multimedia material viz. audio-video may also practice in the Usability Engineering and allied fields. Wireframes including few other prototypes are required in maintaining of the better and healthy man and machine interaction. As the field is growing therefore, it is applicable in other sectors and allied areas and among these agriculture is important one. In agricultural sector different applications of information technologies are increasing and among this Usability Engineering and HCI are important one. In pre production and also in post production; directly and indirectly this technology is emerging and growing. This paper talks about the basics of this technologies and also its current and future technologies with reference to academic potentialities of this branch in Agricultural Informatics programs.
Concentration Distribution and Ecological Risk Assessment of Polycyclic Aroma...Scientific Review SR
The ecological risk assessment of 16 USEPA priority polycyclic aromatic hydrocarbon (PAHs) in water and sediments of Kolo creek, Niger Delta Nigeria was assessed the samples were collected from November, 2018 to June, 2019 from seven locations (A-G) along the creek. The samples were extracted using standard methods and analyzed using gas chromatography (model: HP5890 S). The concentrations of the PAHs in the water and sediment samples ranged between 0.000 - 9.239 µ/L and .002 – 374.35µg/Kg respectively. All the compounds analyzed were detected in all the sampling places, even area far from the flow stations. Hence, the urban runoffs, sewage discharges, and agricultural activities are implicated. Four rings hydrocarbon were present in higher concentration when compared to other PAHs in all sampling sites, with benz (a)anthracene having the highest values in both matrixes. Similarly, lower molecular weight (LMW) PAHs were present in lower concentrations in all sampling sites and they are known to exhibit higher lethal toxicity than the larger PAHs. HMW were present in high concentrations than LMW and are persistent in the environment as a result of their increase resistance to oxidation, reduction and vaporization as molecular weight increases. Similarly, The PAFs of the investigated creek is less than 5%, suggesting existences of minor ecological risks that are insignificance. However, the TEQs detected in high molecular weight showed that there is possibility of cancer to those who may be exposed to the bottom sediment. The indices measured in this habitat may put more pressures to the aquatic organisms and cause drastic changes to their ecosystem which may lead to species extinction.
Volume Fractions of Tantalum Carbides Deduced from the Ta Contents in the Mat...Scientific Review SR
Some superalloys for service at high temperature under stresses are strengthened by tantalum carbides. Their creep resistance depends on the quantity of TaC and this is the reason why it is often important to control the volume fraction of these carbides in the microstructure. Metallographic preparation followed by electron imaging and surface fraction measurements by image analysis is a frequent way for that. Another possibility is to deduce the mass fraction of TaC, and after their volume fraction, from the chemical composition of the matrix when the alloys are only double–phased, on the {matrix + TaC} type. In this work three alloys – chemically designed to be made exclusively of matrix and TaC – were elaborated and isothermally exposed to an elevated temperature for a duration long enough to allow the alloys being at their thermodynamic equilibria. The chemical compositions of the alloy and of its matrix were measured and the results allowed evaluating their TaC mass fractions which were converted in volume fractions. The obtained TaC fractions were compared to results issued from thermodynamic calculations. Good agreement was found for the three alloys, and this allowed to exploit the used software and thermodynamic database to explore further the microstructures at the same high temperature, notably to know the conditions on the Co, Ni, Cr, Ta and C contents to keep the {matrix + TaC} structure and to avoid any possible partial melting.
Assessment of the Coliform Bacterial Load of Some Drinking Water Sources in D...Scientific Review SR
Drinking water samples from 5 sachet water companies, 3 boreholes and 2 taps, collected from different locations of Dutse Metropolis of Jigawa State, Nigeria were analysed for coliform bacterial counts using the Membrane Filtration Technique. All the samples contained some amounts of total coliforms, but mostly within permissible levels. Thirty three percent (33%) of the samples from borehole, 60% from sachet water and 100% from the taps contained faecal coliforms, which indicates contamination. Cultures of the faecal coliforms obtained were morphologically identified using the gram-staining procedure and some series of biochemical tests were carried out in order to identify the organisms. The identified organisms were Escherichia coli (E. coli), Klebsiella sp. and Citrobacter sp. Presence of coliforms above the regulatory set standards indicates contamination and un-safeness of the water for drinking. Presence of organisms such as E. coli, Klebsiella sp. and Citrobacter sp. necessitates improvement in monitoring and water hygiene practices to improve the quality of drinking water in the study area.
Bio Inspired Self-Curing Composite: A Leap into Augmented EnactmentScientific Review SR
Relentless progress has been made on composite materials, their manufacturing processes and their structural design in past few decades. Nevertheless, the approval of composite materials in all engineering disciplines is constrained due to its susceptibility to various kinds of defects during manufacturing stage viz porosity, foreign body inclusion, incorrect fiber volume, bonding defect, fiber misalignment, ply misalignment, incorrect curing cycle, wavy fiber, ply cracking, delamination, fiber microstructural defects etc. Hence there was a requirement of techniques to somehow overcome these defects during the service life of composites being used in various structures and equipment. This promising field of research has made great progress over the past several years, but many procedural encounters are still to be overcome, and there exists a great need for focused research to address several areas of concern. On the other hand, nature has materials that have curing potential and repair strategies ensuring their survival. Sustained development in the field will produce new curing chemistries that possess greater stability, faster kinetics. Tailor-made placement of curing agents is dynamic research subject at the cutting edge of self-curing. New bio-imitative curing agents are closely connected to vascular networks. The purpose of this technical paper is to sort the methodology in line with ongoing research efforts in composites. A perspective on current and future self-curing approaches using this biomimetic technique is offered.
Influence of Information and Communication Technology (ICT) in Tourism Sector...Scientific Review SR
Nepal is a country blessed with natural beauty, diverse culture, majestic Himalayas, religious destination which attracts thousands of tourists every year making the tourism industry progressive to flourish. Information Communication Technology (ICT) proves to be an effective tool for strengthening the tourism industry. Thus, the purpose of this research study is to analyze about the past scenario of tourism industry, advent of ICT in tourism industry, positive impacts of ICT in tourism industry through in-depth interview with tourism experts and people who have worked for tourism since decades. This study is a form of qualitative research where narrative inquiry has been selected and the scenario has been analyzed through themes developed from the narratives. The result reveals that the emerging technology brings positive impacts to tourism industry assisting branding, promotion of the country, enhancing networks through communication and easily booking tours. The proper utilization of ICT helps to welcome tourists and to give identity of our country Nepal to the world.
Reinforcement of Bakelite Moulding Powder in Acrylonitrile Butadiene Rubber (...Scientific Review SR
The document discusses a study that compares the effects of adding two different phenolic resins - cashew nut oil modified phenol-formaldehyde resin (CN-m-PF) and Bakelite moulding powder (BMP) - to carbon black filled acrylonitrile butadiene rubber (NBR). The addition of both resins increases hardness and modulus but decreases some mechanical properties like tensile strength and elongation at break. CN-m-PF provides better processability and mechanical properties than BMP at the same content. However, BMP can also enhance stiffness without processing issues and may be preferred due to its lower cost. The document reports results of various tests measuring properties like curing characteristics, hardness, tensile strength,
Toxic Effect of Glyphosate-Pesticide on Lipid Peroxidation Superoxide Dismuta...Scientific Review SR
The oxidative stress indices lipid peroxidation (LPO), superoxide dismutase (SOD) and catalase (CAT) in juvenile Clarias gariepinus (average weight 200.15 g) exposed to sub - lethal dose 2.40mg/L and 4.98mg/L of glyphosate was investigated over a period of days 1,5,10 and 15 in three replicates. The colorimetric analysis showed increase in lipid peroxidation from 4.55 ±2.14a1 to 12.12± 10.00a1at 2.40mg/L but remain the same at 4.98mg/L (4.55±2.14a1) compared with control (3.03±0.01a1 to 1.51±2.14b1) from day 1 to 15. The SOD activity decreased significantly with time and concentration compared with control. The Catalase activity at day 15 decreased to 0.17±0.05a1 in 2.40mg/L but further increased to 0.28±0.05b1 in 4.98mg/L compared to 0.28±0.02a1 catalase activity as control. The result suggests that glyphosate induce oxidative stress that may overwhelm the antioxidant system in juvenile catfish especially at higher concentrations with long exposure.
Wheeled robots are often utilized for various remote sensing and telerobotic applications because of their ability to navigate through dynamic environments, mostly under the partial control of a human operator. To make these robots capable to traverse through terrains of rough and uneven topography, their driving mechanisms and controllers must be very efficient at producing and controlling large mechanical power with great precision in real-time, however small the robot may be. This paper discusses an approach for designing a quad-wheeled robot, which is wirelessly controlled with a personal computer (PC) by medium-range radio frequency (RF) transceiver, to navigate through unpaved paths with little or no difficulty. An efficient servo-controlled Ackerman steering mechanism and a high-torque driving power-train were developed. The robot’s controller is programmed to receive and respond to RF control signals from the PC to perform the desired motions. The dynamics of the robot’s drivetrain is modeled and analyzed on MATLAB to predict its performances. The robot was tested on various topographies to determine its physical capabilities. Results show that the robot is capable of non-holonomically constrained motions on rough and uneven terrains.
Geometrical Analysis and Design of Tension-Actuated Ackermann Steering System...Scientific Review SR
The tension-actuated steering system is a vehicular steering design that comprises a motorized gear system, pulleys, inelastic string, main steering bar, and a strain gauge. This development is aimed to produce a steering design that could enhance the efficiency of steering systems in quad-wheeled (i.e. four-wheeled) robots. In this work, the steering system of conventional passenger vehicles and existing quad-wheeled robots are reviewed and their technical deficiencies are improved based on cost, power and production factors. Thus, the tension-actuated steering system is proposed as a solution for mechanizing steering functions in quad-wheeled robots. It is expected that this work will stimulate interest and enthusiasm.
A Study of Propensity Score on Influencing Factors of Length of Stay in Hospi...Scientific Review SR
Background: Burns are a global public health problem, which are universal and can happen to anyone. Because the physical functions in children and adults are different, the confounding factors are easy to affect the results of study. Objective: In this study, we aimed to explore influencing factors of the length of hospital stay (LOS) when the confounding factors were excluded by Propensity Score (PS) in children and adults. Methods: Patients hospitalized for burn from 2014 to 2016 were retrieved from the medical record system of a general biggest hospital in Zunyi. A database was established to analyze the influencing factors of LOS between children and adults by the PS. Results A total of 465 children (61.7% males) and 327 (69.7% males) adults were recruited. The average age was 3.61±3.57 years and 42.48±14.76 years in children and adults with burns respectively. Before PS matching, low age and skin grafting were the protective factors for LOS (Hazard Ratio [HR]=0.993 and 0.339). The risk factors of LOS were male (HR=1.234), the burn depth and total body surface area (TBSA), and burn etiology (HR=1.497). After PS matching, only skin grafting (HR=0.080) and treatment within 24 hours (HR=1.865) were the common influencing factors of LOS. Conclusion the confounding factors were excluded by the PS method, and skin grafting was still a protective factor of LOS for both children and adults. The results provide a reference for the promotion of skin grafting to reduce LOS in burn patients.
Concrete is one of the reliable, durable, economical and acceptable construction materials among the building and construction stakeholders worldwide. Performance of concrete could be threatened especially reinforced concrete by some processes such as corrosion, sulfate attack among others. Corrosion of reinforcement in reinforced concrete can be induced by carbonation process. Even though carbonation initiates corrosion, it has been gathered that carbonation could still be of immense benefits to building and construction industries if its mechanism of operation is understudied. This research work has therefore investigated the effect of carbonation on some selected mechanical properties of concrete such as compressive strength, flexural strength, water absorption and weight changes. Concrete cubes and beams of M15 grade with 0.5 % water-cement ratio were prepared and subjected to accelerated carbonation. Their compressive strength, flexural strength, water absorption and weight changes were determined in accordance with the relevant standards. The outcomes show that carbonation improves all the mechanical properties investigated. The use of carbonation can be positively explored in reinforced concrete provided there is adequate nominal cover.
Biogas Synthesis as Means of Solid Waste Management in Kampala, UgandaScientific Review SR
Cattle dung, cooked food waste, and chicken droppings mixed with coffee husks have been used separately and also as mixtures to form anaerobic digestion slurries in a bid to treat to degrade the organic fractions of these wastes and recycle the bio-fertilizer after recovering biogas. Single and mixed substrate slurries evolved significant quantities of methane within 27days together with reduced mass of soil conditioner. The volume of biogas formed in cogeneration mixtures were higher than for single substrate digestion due to the C/N ratio shifting to near 30:1 as a result of mixing. So degradation of organic pollutants was higher in mixed substrate digestion mixtures. Our study yielded average volumes ranging from 315 to 435+ 5.65.mL/L which was in agreement with what is in literature. Digestion of cattle dung, cooked waste foods, and droppings of chicken and mixed substrate slurries using sludge inoculums was very effective in degrading solid waste from homes, thus detoxifying it to bio-fertilizers. Although both single and mixed substrate digestion of waste yielded high enough volumes of biogas; digestion of slurry of mixed organic solid waste substrates is better method of waste management. Digestion of garbage from Kampala should be tested at macro levels at both ambient and mesophilic temperatures. There is need to try out the garbage digestion experiments in the semi-arid towns as well as very cold towns in Uganda.
The Influence of Partial Replacement of Some Selected Pozzolans on the Drying...Scientific Review SR
Concrete is prone to cracking and one of the major causes of cracking is drying shrinkage of the hardened concrete. This research work was carried out to study the influence of partial replacement of some selected pozzolans on the drying shrinkage of concrete. Four pozzolans used in this study, were made to replace cement at various percentages resulting in various concrete mixes. Setting time test was conducted for the various cement mixes using Vicat’s apparatus and drying shrinkage test was done for the concrete test specimens. The results of the setting time indicate that partial replacement of pozzolans with ordinary Portland cement increases both the initial and final setting time of cement as the percentage replacement increases. Similarly, drying shrinkage results show that concrete made with Groundnut Shell Ash (GSA) and Locust Bean Pod Ash (LBA) at 12% replacement will have a stable and better shrinkage resistance than the control at both 56 days and 90 days. Meanwhile, the control concrete gives a better drying shrinkage at 28 days curing. In conclusion, the results show that pozzolanas [Bamboo Leaves Ash (BLA), Locust Bean Pod Ash (LBA), Sugarcane Bagasse Ash (SBA) and Groundnut Shell Ash (GSA)] can successfully replace cement up to 12% without necessarily affecting the shrinkage ability of the produced concrete. It also shows that Groundnut Shell Ash (GSA), Locust Bean Pod Ash (LBA) and Bamboo Leaves Ash (BLA) are more resistance to drying shrinkage than the control.
Study on the Granulation of FLY Ash from Thermal Power StationScientific Review SR
This study examined the granulation of fly ash from a thermal power station in Bulgaria to utilize this waste material. The highest yield of granules was achieved using clayish slip as a binder. Adding sodium phosphate as a reinforcing additive increased the granule yield and strength. Sintering the granules increased their density, decreased porosity, and substantially improved their compression strength up to 2.2 MPa, making them suitable for use as a filler in light concretes. The granulation process and additions showed potential for utilizing fly ash waste from thermal power stations.
Machining Versus Molding Tolerances in Manufacturing Automotive Sealing SystemsScientific Review SR
The automotive industry has been at the forefront of converting traditional metal parts to plastics. The latter surely offer greater design freedom, opportunity for consolidation, fewer assembly operations, reduced secondary finishing, weight reduction, lower total system costs, a range of properties tailored to specific applications, the ability to withstand temperatures, immunity to most chemicals and corrosive environments. They offer processing in many colors, electrical non-conductivity (insulation from electrical shocks), good thermal breaks (“warmth-to-the-touch”), and low sound transmission (tendency to muffle noise). Nonetheless, plastics have only tapped an estimated 15% of their tremendous potential to replace metals. This is particularly to increase with newer high-performance plastics, increasing sophistication in alloying and blending technologies, and use of computer-aided design and engineering (CAD/CAE) systems. The latter enable engineers to visualize complex parts and molding tools more effectively and faster than ever before. This article identifies fundamental steps and requirements to conduct an efficient and successful conversion of metallic parts to plastics, reviewing the replacement design process from concept to production; an under-the-hood rear retainer for Ford Motor Company is detailed as a case study.
Sinthesis and Properties of Marble-Like Glass-Ceramics Using of Ash from Ther...Scientific Review SR
Color marble-like glass-ceramic materials were obtained through thermal treatment of glasses of the system CaO-Al2O3-SiO2 by using natural materials with the introduction of waste materials - ash from thermal power plants (TPP). The melting of the glass batch was in corundum crucibles at 1450oC with an isothermal hold of 60 min. The glasses obtained was fritted in distilled water and dried for 6 hours at 100oC, then completely crushed and divided into fractions with grain size of 0.8 mm, 1.0 mm, 2 mm, 2.5 mm and over 2.5 mm. It was found that the use of ash from TPP lead to higher values of degree of transformation (crystallization) than using base composition. Values of Avramy parameter’s in the range n=1,0 ÷ 1,6 are showed that crystallization of the glass frit is largely heterogeneous and crystal growing starts from the surface. The introduction of ash from TPP to native glasses carry out to significant reduction of energy of crystallization by Ес=289 kJ/mol to Ec=221 kJ/mol. The glass-ceramic materials were obtained through a one stage crystallization - 1050÷1070оС and an isothermal hold of 60 min., colored white, yellow brown to dark brown. The main crystalline phase in glass-ceramics is β-vollastonite with needle habit, size of crystals - ĺ = 40 ÷ 120 μm and d <5 μm in quantities 37 ÷ 42%. As secondary phases depending on the amount of ash have been identified - the anorthite, gehlenite and α-quartz with prismatic habit were appeared. The obtained glass-ceramic materials have a marble-like effect and technical parameters compared with natural granite and marble and have higher values of density, micro hardness, speed grinding, bending strength and chemical resistance. That’s why they can be used in construction such as lining materials.
Basics of Electrocardiogram
CONTENTS
●Conduction System of the Heart
●What is ECG or EKG?
●ECG Leads
●Normal waves of ECG.
●Dimensions of ECG.
● Abnormalities of ECG
CONDUCTION SYSTEM OF THE HEART
ECG:
●ECG is a graphic record of the electrical activity of the heart.
●Electrical activity precedes the mechanical activity of the heart.
●Electrical activity has two phases:
Depolarization- contraction of muscle
Repolarization- relaxation of muscle
ECG Leads:
●6 Chest leads
●6 Limb leads
1. Bipolar Limb Leads:
Lead 1- Between right arm(-ve) and left arm(+ve)
Lead 2- Between right arm(-ve) and left leg(+ve)
Lead 3- Between left arm(-ve)
and left leg(+ve)
2. Augmented unipolar Limb Leads:
AvR- Right arm
AvL- Left arm
AvF- Left leg
3.Chest Leads:
V1 : Over 4th intercostal
space near right sternal margin
V2: Over 4th intercostal space near left sternal margin
V3:In between V2 and V4
V4:Over left 5th intercostal space on the mid
clavicular line
V5:Over left 5th intercostal space on the anterior
axillary line
V6:Over left 5th intercostal space on the mid
axillary line.
Normal ECG:
Waves of ECG:
P Wave
•P Wave is a positive wave and the first wave in ECG.
•It is also called as atrial complex.
Cause: Atrial depolarisation
Duration: 0.1 sec
QRS Complex:
•QRS’ complex is also called the initial ventricular complex.
•‘Q’ wave is a small negative wave. It is continued as the tall ‘R’ wave, which is a positive wave.
‘R’ wave is followed by a small negative wave, the ‘S’ wave.
Cause:Ventricular depolarization and atrial repolarization
Duration: 0.08- 0.10 sec
T Wave:
•‘T’ wave is the final ventricular complex and is a positive wave.
Cause:Ventricular repolarization Duration: 0.2 sec
Intervals and Segments of ECG:
P-R Interval:
•‘P-R’ interval is the interval
between the onset of ‘P’wave and onset of ‘Q’ wave.
•‘P-R’ interval cause atrial depolarization and conduction of impulses through AV node.
Duration:0.18 (0.12 to 0.2) sec
Q-T Interval:
•‘Q-T’ interval is the interval between the onset of ‘Q’
wave and the end of ‘T’ wave.
•‘Q-T’ interval indicates the ventricular depolarization
and ventricular repolarization,
i.e. it signifies the
electrical activity in ventricles.
Duration:0.4-0.42sec
S-T Segment:
•‘S-T’ segment is the time interval between the end of ‘S’ wave and the onset of ‘T’ wave.
Duration: 0.08 sec
R-R Interval:
•‘R-R’ interval is the time interval between two consecutive ‘R’ waves.
•It signifies the duration of one cardiac cycle.
Duration: 0.8 sec
Dimension of ECG:
How to find heart rhytm of the heart?
Regular rhytm:
Irregular rhytm:
More than or less than 4
How to find heart rate using ECG?
If heart Rhytm is Regular :
Heart rate =
300/No.of large b/w 2 QRS complex
= 300/4
=75 beats/mins
How to find heart rate using ECG?
If heart Rhytm is irregular:
Heart rate = 10×No.of QRS complex in 6 sec 5large box = 1sec
5×6=30
10×7 = 70 Beats/min
Abnormalities of ECG:
Cardiac Arrythmias:
1.Tachycardia
Heart Rate more than 100 beats/min
Test bank clinical nursing skills a concept based approach 4e pearson educati...rightmanforbloodline
Test bank clinical nursing skills a concept based approach 4e pearson education
Test bank clinical nursing skills a concept based approach 4e pearson education
Test bank clinical nursing skills a concept based approach 4e pearson education
Emotional and Behavioural Problems in Children - Counselling and Family Thera...PsychoTech Services
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
Solution manual for managerial accounting 18th edition by ray garrison eric n...rightmanforbloodline
Solution manual for managerial accounting 18th edition by ray garrison eric noreen and peter brewer_compressed
Solution manual for managerial accounting 18th edition by ray garrison eric noreen and peter brewer_compressed
English Drug and Alcohol Commissioners June 2024.pptxMatSouthwell1
Presentation made by Mat Southwell to the Harm Reduction Working Group of the English Drug and Alcohol Commissioners. Discuss stimulants, OAMT, NSP coverage and community-led approach to DCRs. Focussing on active drug user perspectives and interests
Fit to Fly PCR Covid Testing at our Clinic Near YouNX Healthcare
A Fit-to-Fly PCR Test is a crucial service for travelers needing to meet the entry requirements of various countries or airlines. This test involves a polymerase chain reaction (PCR) test for COVID-19, which is considered the gold standard for detecting active infections. At our travel clinic in Leeds, we offer fast and reliable Fit to Fly PCR testing, providing you with an official certificate verifying your negative COVID-19 status. Our process is designed for convenience and accuracy, with quick turnaround times to ensure you receive your results and certificate in time for your departure. Trust our professional and experienced medical team to help you travel safely and compliantly, giving you peace of mind for your journey.www.nxhealthcare.co.uk
Cyclothymia Test: Diagnosing, Symptoms, Treatment, and Impact | The Lifescien...The Lifesciences Magazine
The cyclothymia test is a pivotal tool in the diagnostic process. It helps clinicians assess the presence and severity of symptoms associated with cyclothymia.
Digital Health in India_Health Informatics Trained Manpower _DrDevTaneja_15.0...DrDevTaneja1
Digital India will need a big trained army of Health Informatics educated & trained manpower in India.
Presently, generalist IT manpower does most of the work in the healthcare industry in India. Academic Health Informatics education is not readily available at school & health university level or IT education institutions in India.
We look into the evolution of health informatics and its applications in the healthcare industry.
HIMMS TIGER resources are available to assist Health Informatics education.
Indian Health universities, IT Education institutions, and the healthcare industry must proactively collaborate to start health informatics courses on a big scale. An advocacy push from various stakeholders is also needed for this goal.
Health informatics has huge employment potential and provides a big business opportunity for the healthcare industry. A big pool of trained health informatics manpower can lead to product & service innovations on a global scale in India.
At Malayali Kerala Spa Ajman we providing the top quality massage services for our customers.
Our massage center prioritizes efficiency to ensure a quality massage experience for our clients at Malayali Kerala Spa Ajman. We offer a convenient appointment system and precise massage services.
Reach us at Villa No 7, Near Ammar Bin Yasir Street Al Rashidiya 2 - Ajman - United Arab Emirates.
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nursing management of patient with Empyema pptblessyjannu21
prepared by Prof. BLESSY THOMAS, SPN
Empyema is a disease of respiratory system It is defines as the accumulation of thick, purulent fluid within the pleural space, often with fibrin development.
Empyema is also called pyothorax or purulent pleuritis.
It’s a condition in which pus gathers in the area between the lungs and the inner surface of the chest wall. This area is known as the pleural space.
Pus is a fluid that’s filled with immune cells, dead cells, and bacteria.
Pus in the pleural space can’t be coughed out. Instead, it needs to be drained by a needle or surgery.
Empyema usually develops after pneumonia, which is an infection of the lung tissue. it is mainly caused due in infectious micro-organisms. It can be treated with medications and other measures.
Biodegradation of Organophosphorous Pesticide: Chlorpyrifos
1. Scientific Review
ISSN(e): 2412-2599, ISSN(p): 2413-8835
Vol. 5, Issue. 1, pp: 8-18, 2018
URL: https://arpgweb.com/journal/journal/10
DOI: https://doi.org/10.32861/sr.51.8.18
Academic Research Publishing
Group
*Corresponding Author
8
Original Research Open Access
Biodegradation of Organophosphorous Pesticide: Chlorpyrifos
Farjana A. Koly*
Institution of Radiation and Polymer Technology, Atomic Energy Research Establishment, Dhaka, Bangladesh
Ruhul A. Khan
Institution of Radiation and Polymer Technology, Atomic Energy Research Establishment, Dhaka, Bangladesh
Abstract
At the present time extensive varieties of pesticides are being used but the demand for organophosphorus pesticide is
increasing globally to control insect. Chlorpyrifos is a broad spectrum, moderately toxic, chlorinated
organophosphate insecticide that is synthetic in origin and is normally ester or thiol derivatives of phosphoric,
phosphonic or phosphoramidic acids. The mode of action involves inhibiting acetyl cholinesterase leading to
accumulation of acetylcholine causing neurotoxicity. It is being transported by circulation far away from site of
application leading to pollution of environment. Due to its persistent in nature, it is not only severely detrimental to
the target pests, but also causes toxicity in non-target organisms including humans. It is thus critically important to
develop methods to eradicate these pollutants from the environment. Lately, research activities in this area have
demonstrated that microorganisms are potential tool in decaying chlorpyrifos into less harmful and non-toxic
metabolites through a process known as bioremediation. This article therefore aims at giving an overview of the
present status of research and future prospects in bioremediation of chlorpyrifos.
Keywords: Pesticide; Acetyl cholinesterase; Neurotoxicity; Persistent; Pollutant; Pollution; Chlorpyrifos; Bioremediation;
Microorganism; Environment.
CC BY: Creative Commons Attribution License 4.0
1. Introduction
Enhanced agricultural activities throughout the world have been required large scale synthesis of xenobiotic
compounds leading to considerable pollution of the environment. Pesticides as agrochemicals were introduced in
agriculture system to meet the demand of increased food needs of growing population act by preventing, destroying,
repelling, or mitigating any pest [1, 2]. Despite numerous merits, they are now considered a necessary evil for their
multifaceted toxicity, persistence and recalcitrance nature. It is ironic that only 0.3% of applied pesticide reaches to
the target pest, and the rest which are not utilized, eventually dissipated into the environment [3, 4]. Pesticides
commonly used during agricultural activities include organochlorines, organophosphates, pyrethroids and
carbamates [5, 6]. Among these pesticides, organophosphorus pesticide alone is account for about 38% of the total
pesticides used globally. The increase use of organophosphorus pesticide is because of its high effectiveness against
target pests and relatively low toxicity to non-target organisms than other groups of pesticides [7, 8].
Chlorpyrifos is one of the most widely used chlorinated organophosphorous pesticide having the chemical name
O, O-diethyl O-3, 5, 6-trichloropyridyl phosphorothioate (Fig. 1) and the trade names Lorsban, Agromil, Dhanwan,
Dorson, Omexan, Dursban, Suscon Green, Empire, Equity to name a few. It is effective against a broad spectrum of
insect pests of economically important crops which has been extensively used globally since 65s as an insecticide to
control crop pests, mosquito as well as soil dwelling grubs, borers, cutworms, corn rootworms, cockroaches, grubs,
flea beetles, flies, termites, fire ants lice and subterranean termites. It is available in a variety of formulations, such as
granules, wettable powder, dustable powder and emulsifiable concentrate. Chlorpyrifos is registered for use in nearly
100 countries and is annually applied to approximately 8.5 million crop acres [9]. However, this continuous and
excessive use in agriculture sector has resulted in the persistence of their residues and contamination of various
environmental compartments, such as soil, water and air. The contamination has been found up to about 24
kilometers from the site of application [8]. For instance, residues of chlorpyrifos have been detected in fruits,
vegetables, and also in water and soil samples, in marine, sediments, streams, sumps, sloughs, rivers, urban storm
drains, freshwater lakes, groundwater, fog, rain and air in many parts of the world [10].
The half-life of chlorpyrifos generally ranges between 10 and 120 days in soil but can range from 2 weeks to
over 1 year depending on abiotic factors such as soil type, climate, and other conditions [7, 11]. In environment
chlorpyrifos is hydrolyzed to 3, 5, 6-trichloropyridinol (TCP), which has more water solubility and therefore more
mobile and easily leaches into ground as well as surface water with greater efficiency than chlorpyrifos itself [12,
13]. Half-life of TCP ranges from 65 to 360 days in soil and is reported as persistent pollutant by US EPA [14].
Chlorpyrifos is acutely toxic to bees, birds, mammals, aquatic life, and certain species of algae. Poisoning from
chlorpyrifos and TCP may affect the central nervous system, the cardiovascular system, endocrine system as well as
the respiratory system of non-target organisms [15, 16]. Acute exposure can result in such symptoms as numbness,
tingling sensation, incoordination, dizziness, vomiting, sweating, nausea, stomach cramps, headache, vision
disturbances, muscle twitching, drowsiness, anxiety, slurred speech, depression, confusion and in extreme cases,
respiratory arrest, unconsciousness, convulsions, and even death [17].
2. Scientific Review
9
Due to the environmental concern associated with the accumulation of organophosphorus compounds in food
products and water supplies, here is urgent to develop safe, convenient, and economically feasible methods for its
detoxification from the environment. Mechanisms for cleanup of chlorpyrifos using conventional methods such as
chemical treatment, volatilization and incineration have met public opposition because of the use of large volume of
acids and alkalis and accumulation of recalcitrant residuals [18]. Generally, physical and chemical cleanup
technologies are expensive and sometimes not much effective [19]. Biodegradation processes are increasingly
attracting scientists’ interest as novel technological methods to detoxify contaminated natural matrices and it is a
cost-effective, reliable as well as easy to use technique which does not pose threat of secondary pollution to the
environment [20, 21]. It exploits the use of microorganisms whether bacteria or fungi that show the capability to
degrade chlorpyrifos through specific pathways by using them as carbon and energy sources rendering the
contaminants harmless or less toxic products in most cases [22].
The main objectives of this article, however are to give a chronological overview on the research efforts
undertaken worldwide to develop sensitive methods for biodegradation of chlorpyrifos as well as critically review
mode of action and recent biotechnological advancements in the development of bio-catalysts and genetically
modified organisms for chlorpyrifos and their possible application in bioremediation of contaminated ecosystems.
2. Mechanism of Action of Chlorpyrifos and Its Effects
Chlorpyrifos works basically the same way both in insects and other animals including humans through
impairment of nervous system. It enters into organisms by contact and ingestion in addition with absorbed through
the skin, gut and pulmonary membranes [23]. Inside animals it is converted to their oxidized forms or oxon which is
about 3000 times as potent against the nervous system as chlorpyrifos itself [24, 25]. The mechanism of action by
which chlorpyrifos-oxon exerts its toxic effect is related to binding and irreversibly inhibiting acetylcholinesterase
(AChE-ase), an enzyme located in the nervous system and in the neuromuscular junction [26-28]. AChE-ase
involves in the breaks down of a neurotransmitter chemical acetylcholine (ACh) that involves in the transmission of
impulses across neuromuscular junction. The stimulant effect of ACh is rapidly hydrolyzed to avoid over-stimulating
or overwhelming the nervous system by AChE-ase activity. The inhibition of AChE-ase by clorpyrifos oxon results
in the accumulation of ACh, with consequent serious disruption of nervous activity [29]. Reduction in
acetylcholinesterase activity to 10-20% of normal activity in man results usually in severe muscle paralysis,
convulsions and ultimately death [30]. The mechanism of action of chlorpyrifos is shown in Fig. 2.
The exposure of chlorpyrifos has also been shown to interact with macromolecule synthesis (DNA, RNA, and
proteins), neurotransmitter receptors and signal transduction pathways. Besides, it impedes respiration in the livers
of laboratory animals by interacting with the activity of ATPase and cholesterol ester hydrolase, enzymes associated
with cellular respiration and normal reactions to stress respectively [31, 32].
3. Environment Fate and Pathway of Degradation of Chlorpyrifos
The fate of chlorpyrifos is affected not only by its own physicochemical properties, but also by characteristics of
the soil, environmental conditions and management practices [33] (Table 1). Its persistence increases with decreased
temperature, decreased pH, and decreased light. It has also been reported to have short to moderate persistence in the
environment as a result of several non-biological methods including volatilization, photolysis, abiotic hydrolysis,
and also by microbial degradation that might occur concurrently. The half-life may varies from 10 to 120 days that
has been attributed to different environmental factors, the most important of which are soil pH, temperature,
moisture content, organic carbon content, and pesticide formulation [34]. The dissipative half-life is significantly
longer in organic soils than mineral soils. As a result of photolysis and oxidation in air and on foliar surfaces,
chlorpyrifos is oxidized to its oxon form, chlorpyrifos-oxon. Volatilization governs dissipation from foliage in the
initial 12h after application, but cannot works in the days after application as the formulation adsorbs strongly to
foliage or penetrates more deeply into the soil matrix. The most significant step for the complete degradation of the
molecule in soil involves hydrolysis of P-O-alkyl and P-O-aryl bonds either enzymatically (as a result of microbial
activity) or spontaneously to yield 3, 5, 6-trichloropyridinol (TCP) and Diethylthiophosphoric acid (DETP) from
either chlorpyrifos or chlorpyrifos-oxon [35]. However, hydrolysis is slower in water containing clay minerals,
humate, dissolved organic matter, and suspended sediment [36].
The major intermediate hydrolysis product of chlorpyrifos is TCP with greater water solubility than chlorpyrifos
and causes the widespread contamination in environment. Also, TCP retards the proliferation of chlorpyrifos
degrading microorganisms owing to its antimicrobial properties that’s why in some earlier studies chlorpyrifos was
reported to be resistant to the phenomenon of enhanced biodegradation [20, 21]. The later studies revealed
considerable capacity of microorganisms in the efficient degradation of chlorpyrifos into CO2 and organic matter
[37-39]. Fig. 3 illustrates the degradation pathway of chlorpyrifos.
Table-1. Physicochemical and environmental fate properties of Chlorpyrifos [40]
Property Values for Chlorpyrifos
Empirical formula C9H11Cl3NO3PS
Molecular mass 350.6 g/mol
Melting point 42-44°C
Vapor pressure (25°C) 1.0 x 10-3
Pa
Water solubility 0.39 mg/L at 19°C
3. Scientific Review
10
0.941 mg/l at 20°C
0.588 mg/L at 20°C
Hydrolysis (t½) pH 5.0 : 73days
pH 7.0 : 72days
pH 9.0 : 16days
Soil sorption coefficient, Koc 652-30, 381 L/kg
Dissociation characteristics Practically non dissociative by
nature
Partition coefficient octanol or water Log Kow = 5.0 at 24.5°C
Log Kow = 4.7 at 20°C
Henry’s Law Constant (determines
solubility of gas in liquid)
1.10 × 10−5
atm m−3
mol−1
4. Bioremediation–A Potential Detoxification Technology
Bioremediation has now emerged as an innovative technology that is critically important for the clean-up of
polluted sites. This technology is cost effective that does not pose the threat of secondary pollution to the
environment. The contaminated soil, sediment as well as groundwater can be treated by bioremediation. The process
can be carried out by using indigenous microorganisms or by adding an enriched culture of microorganisms.
Degradation strategies exhibited by microbes include co-metabolism and catabolism. Incidental metabolism or co-
metabolism is the biotransformation of a molecule coincidental to the normal metabolic functions of the microbe to
partial intermediate with no net benefit. The later, catabolism or mineralization involves complete degradation and
utilization of the degraded products as a nutritive or energy source. However, studies conducted in soil and water has
led to the conclusion that the microbial activities are singularly most important mechanism in the degradation and
detoxification of chlorpyrifos [41].
4.1. Biodegradation by Bacteria
Bacteria are considered as indispensable tools by the researchers now have proven to be potential candidate in
the field of bioremediation of pesticide contaminated areas. Repeated application of pesticides for many years in any
area has resulted in the evolution and adaptation of bacteria capable of degrading these anthropogenic compounds in
that area [42]. Researchers have isolated and characterized bacteria showing potentiality towards degradation of
chlorpyrifos. Some important chlorpyrifos degrading bacteria are listed in Table 2.
Table-2. Potential chlorpyrifos degrading bacteria
Bacteria
Rate of
degradation
(%)
Concentration
(mg/L)
Duration
(hours) Reference
Enterobacter sp. 100 100 240 [38]
Alcaligenes faecalis 100 250 48 [43]
Sphingomonas sp. 100 100 48 [14]
Paracoccus sp. 100 50 96 [28]
Xanthomonas sp. 4R3-M1,
Pseudomonas sp. 4H1-M3,
and
Rhizobium sp. 4H1-M1
- 10 - [17]
Stenotrophomonas sp. YC-1 100 100 24 [44]
Gordonia sp. JAAS1 100 110 72 [19]
Cellulomonas fimi 100 50 72 [45]
Acinetobacter sp. MemCl4 98 - 144 [20]
Bacteria capable of degrading chlorpyrifos were also reported to promote several kinds of plants. Akbar and
Sultan [35] isolated and characterized two bacteria Achromobacter xylosoxidans JCp4 and Ochrobactrum FCp1 able
to degrade 93%-100% of input concentration (200mg/kg) of chlorpyrifos within 42days in sterilized as well as non-
sterilized soils. These strains showed substantial plant growth promoting traits such as phosphate solubilization and
production of ammonia and indole acetic acid. Feng, et al. [46] studied some endophytic bacteria with dual functions
stimulating plant growth and degrading pollutants. They isolated five endophytic bacteria from chlorpyrifos treated
rice plants showing more than 90% degradation of chlorpyrifos in 24h when the initial concentration was lower than
530 mg/L and identified as Pseudomonas aeruginosa RRA, Bacillus megaterium RRB, Sphingobacterium
siyangensis RSA, Stenotrophomonas pavanii RSB and Curtobacterium plantarum RSC. All of these species shown
to possess some plant growth promotional traits, including production of indole acetic acid and siderophore,
secretion of phosphate solubilizing chemicals and 1-aminocyclopropane-1-carboxylate deaminase.
A bacterial strain Bacillus subtilis Y242 was isolated from agricultural wastewater and the efficiency of
degrading chlorpyrifos was examined under different culture conditions. The bacterium was able to utilize
chlorpyrifos as a sole carbon and energy source and showed 95.12% chlorpyrifos decomposition within 48h on a
medium containing concentration up to 150 mg/L [47]. Fulekar and Geetha [48] reported the adaptation of
4. Scientific Review
11
Pseudomonas aeruginosa NCIM 2074 to chlorpyrifos up to a concentration of 75 mg/L in a mineral salt medium.
However, higher concentrations were detrimental to the growth and survival of the bacterium. Chishti and Arshad
[49] reported growth linked biodegradation of chlorpyrifos (100 mg/L) by Agrobacterium sp. and Enterobacter sp.
under shaking conditions. Up to 92% of the spiked chlorpyrifos was degraded within 18days at a neutral pH 7.0 and
incubation temperature of 30°C. Eissa, et al. [18] isolated Bacillus sp. SMF5 capable of degrading chlorpyrifos and
utilizing it as a sole source of carbon and phosphorus. The degradation was found to be optimum at 30°C and pH
7.0.
TCP, the intermediate metabolite of chlorpyrifos, acts as a buffer in the soil and sediment that prevents the
proliferation of chlorpyrifos degrading microbes. There have been no reports of mineralization of chlorpyrifos since
its first use in 1965 [21]. Recently researchers have reported extensive mineralization of TCP to carbon dioxide to
avoid its accumulation in the environment. Bacillus firmus [50], Ralstonia sp. T6 [51], Bacillus pumillus C2A1 [52],
Enterobacter sp. B-14 [38], Sphingobacterium sp. JAS3 [19], Cupriavidus sp. DT-1 [53], Alcaligenes sp. JAS1 [54],
Paracoccus sp. TRP [28], Xanthomonas sp. 4R3-M1 and Pseudomonas sp. 4H1M3 [17] are few bacteria that can
mineralize the chlorpyrifos effectively. Feng, et al. [55] for the first time isolated a pure culture of bacteria capable
of mineralizing TCP under aerobic conditions by a reductive de-chlorination pathway to yield CO2, chloride and
some unidentified polar metabolites. The bacterium was identified as a Pseudomonas sp. ATCC 700113. Li, et al.
[14] demonstrated that the concentration of the chlorpyrifos had apparently no effect on the degradation rate, but
when the concentration was higher than 200 mg/L, the bacterium stopped degrading its intermediate TCP and grew
very slowly. The growth experiments by Rani, et al. [56] showed that Providencia stuartii MS09 was able to grow in
the presence of high concentrations (50-700mg/L) of chlorpyrifos and utilized it as a source of carbon. However, the
optimum concentration that supported bacterial growth over 24h was found to be 50-200mg/L chlorpyrifos, whereas
at higher concentrations (300-700mg/L) an increased lag phase was observed, without inhibiting growth of the
pesticide-utilizing bacterium. An effective chlorpyrifos-degrading bacterial strain, Mesorhizobium sp. HN3, was
isolated and characterized by Jabeen, et al. [57]. This strain was capable of converting chlorpyrifos and TCP to
diethylthiophosphate and of 3,5,6trichloro-2-methoxypyridine, respectively up to 400mg/L initial concentration at
wide range of temperatures (30–40°C) and pH (6.0–8.0) while optimal degradation was achieved at 37°C and neutral
pH (7.0) at an initial inoculum density 2 × 107
colony forming unit/mL of culture medium. Xu, et al. [58] reported
complete mineralization of 100 mg/L chlorpyrifos by co-culturing of Serratia sp. a potential chlorpyrifos degrader
and Trichosporon sp. a TCP mineralizing strain within 24h of incubation period. The results obtained from previous
study clearly indicated that bacteria play a crucial role in detoxifying chlorpyrifos contaminated area.
4.2. Biodegradation by Fungi
Besides bacteria, many fungal isolates have been reported as potential degraders of chlorpyrifos as fungi
account for up to 75% of soil microbial biomass [59]. Bioremediation in which fungi are involved is referred to as
mycoremediation [39]. Only a few studies indicated that fungi degrade chlorpyrifos in liquid media. Ivashina [60]
studied chlorpyrifos degradation by several microbial cultures maintained in liquid media containing 10ppm
chlorpyrifos. Dissipation was more rapid in a sucrose-supplemented media containing Trichoderma sp. and glucose
supplemented media containing Bacillus sp. than in control media containing no microorganisms. Chlorpyrifos
disappeared from the microbial cultures in a linear fashion over a 2-week period. Jones and Hastings [61] isolated
several forest fungi namely Trichoderma harzianum, Penicillium vermiculatum, and Mucor sp. capable of
metabolizing 50ppm chlorpyrifos. After 28days, chlorpyrifos and its metabolite TCP were present in all cultures at
levels of 2-5% and 1-14%, respectively. Fang, et al. [62] reported pH and temperature dependent biodegradation of
chlorpyrifos by the Verticillium sp. DSP and concluded that the maximum degradation of 1mg/L chlorpyrifos was
achieved at pH 7.0 and 35°C. Some degree degradation of chlorpyrifos by the yeast Saccharomyces cervisiae was
reported by Lal and Lal [63]; where half the initial chlorpyrifos was recovered 12h after the cultures were inoculated
with 1-10ppm. Bumpus, et al. [64] reported the ability of Phanerochaete chrysosporium to degrade 27.5% of
chlorpyrifos during the 18days incubation in nitrogen-limited stationary cultures. Chen, et al. [65] isolated and
characterized a new fungal strain Cladosporium cladosporoides strain Hu-01 which has high chlorpyrifos
degradation activity. It utilized 50 mg/ml of chlorpyrifos as the sole carbon source and was able to tolerate upto 500
mg/ml of chlorpyrifos concentration. The optimum conditions for degradation were found to be 26.8°C and pH 6.5.
It was able to metabolize chlorpyrifos completely under these conditions and no accumulation of TCP was observed.
4.3. Biodegradation by Co-culture of Micro-Organisms
Although researchers were successful in the isolation of many chlorpyrifos degrading microorganisms, however,
there are very few reports of single microorganisms capable of efficiently degrading chlorpyrifos and its toxic
metabolite TCP completely. Therefore, some approaches have been made towards co-culturing of microorganisms to
ensure complete degradation of chlorpyrifos which was proven more efficient than single culture technique. John, et
al. [66] assembled a novel bacterial consortium namely C5 consisting of Staphylococcus warneri CPI2,
Pseudomonas putida CPI9 and Stenotrophomonas maltophilia CPI15 showing 90% degradation of chlorpyrifos (125
ppm) in 8days of incubation period at pH 7.0 and temperature 30ºC. The co-culture of a bacterial strain
Cellulomonas fimi, that could transform chlorpyrifos to TCP and a fungal strain Phanerochaete chrysosporium that
could utilize TCP showed complete mineralization of 50 mg/L CP within 16h at 33ºC and at pH 8.4 [45].
Sethunathan and Yoshida [67] reported degradation of CP by co-culture of Flavobacterium sp. and Pseudomonas
diminuta in liquid media which were initially isolated from a diazinon treated field and by parathion enrichment,
respectively. Xu, et al. [58] observed complete mineralization of 50 mg/ml of chlorpyrifos within 18h at 37°C by co-
culturing Serratia sp. that could transform chlorpyrifos to TCP and Trichosporon sp. that further mineralized TCP.
5. Scientific Review
12
Sasikala, et al. [68] reported efficient development of a consortium using four bacterial isolates namely
Pseudomonas putida (NII 1117), Klebsiella sp., (NII 1118), Pseudomonas stutzeri (NII 1119), and Pseudomonas
aeruginosa (NII 1120) capable of degrading chlorpyrifos to produce chlorpyrifos-oxon and Diethylphosphorothioate
and concluded that the intracellular fractions of the consortium exhibited more organophosphorus hydrolase activity
(0.171 ± 0.003 U/mL/min) while experiment was carried out at neutral pH and temperature 37°C with chlorpyrifos
concentration 500 mg/L.
4.4. Enzymes Involved in Chlorpyrifos Biodegradation
Enzyme based bioremediation has now become emerging technology to decontaminate pesticide residues from
agricultural soils and wastewater. Among various strategies used by the microorganism, the enzymes play a central
role in the biodegradation of organophosphorous pesticide. Like most other organophosphorous pesticide, the most
commonly studied enzymes for chlorpyrifos degradation are related to the phosphotriesterase (PTEs) or
organophosphate hydrolase (OPH), which are capable of hydrolyzing organophosphorus pesticides at the central
phosphorus atom containing P–O, P–F and P–S bonds. OPH activities in microbes is influence by various factors
like varying incubation time period, pH, temperature, carbon sources, metal ions and various chemical compounds.
Researchers had reported maximum OPH activity at 35°C and 37°C in Pseudomonas stutzeri S7B4 and
Pseudomonas aeruginosa NL01, respectively [69]. Many researchers reported alkaline pH to be the optimum for
maximum OPH activity [70]. Ningfeng, et al. [71] observed highest OPHC2 activity in Pseudomonas
pseudoalcaligenes at pH 9.0. The OPH enzymes include Methyl Parathion Hydrolase (MPH), Mevalonate
Pyrophosphate Decarboxylase (MPD) etc. The OPH was first isolated from Pseudomonas diminuta MG has the
ability to hydrolyze a wide range of organophosphorus compounds [72]. Yang, et al. [73] discovered an opdA
enzyme from A. radiobacter P230 that degraded a broad range of organophosphates. Singh, et al. [38] studied and
reported a novel PTE enzyme system isolated from Enterobacter sp. B-14 encoding gene that had a different
sequence from known organophosphate-degrading opd gene. Cui, et al. [74] isolated Methyl Parathion Hydrolase
(MPH, E.C.3.1.8.1) differ from OPH from Plesiomonas sp. M6 that was proven to be crucial enzyme for
hydrolyzing a broad spectrum of organophosphorus compounds. Khalid, et al. [75] identified Pseudomonas putida
CP-1 that can grow efficiently on phosphorus free media while utilizing chlorpyrifos as a sole source of phosphorus.
Cell free extract (CFE) obtained from Pseudomonas putida CP-1 further confirmed the triesterase activity as well as
presence of phosphotriesterase as it hydrolyzes chlorpyrifos to yield TCP as a major metabolite. Most of the
chlorpyrifos hydrolyzing enzymes are reported from bacterial species while there are few reports available in
literature in case of fungal species. However, several fungi are reported to produce enzymes and therefore, have been
suggested as potential candidates for bioremediation. Gao, et al. [11] purified and characterized a novel chlorpyrifos
hydrolase from cell extract of the fungi Cladosporium cladosporioides Hu-01 and reported its involvement in the
degradation of chlorpyrifos.
4.5. Genes Involved in Chloryrifos Biodegradation
With rapid progression in the avenue of metagenomics and genome sequencing, the scope for investigating the
novel genes possessing pesticide degradative efficiencies have opened up. In order to explore and successful
implementation of these technologies in the field of remediation, it is crucial to identify microorganisms containing
the efficient genes to degrade chlorpyrifos. Various catabolic genes including organophosphate-degrading genes
(opd) and mpd from different microorganisms from different geographical regions have been characterized by many
researchers. Most of these catabolic genes involved in degradation are extra-chromosomal or genomic while some
other found in transposons [7, 76]. The first described opd gene was found in Pseudomonas diminuta, and was
shown to be present on a plasmid [77]. A similar gene, opdA, is present in the chromosome of Agrobacterium
radiobacter [78]. Guha, et al. [79] also reported the involvement of plasmids in degradation of chlorpyrifos by
Micrococcus sp. isolated from soil. Singh and Walker [7] were successful in cloning opd gene capable of encoding
OPH from geographically different regions and taxonomically different species. The opd genes isolated from
Bacillus diminuta and Flavobacterium sp. ATCC 27551 were located on non-homologous plasmids that possess
100% similarity in DNA sequences. Very recently, a novel gene opdE (753 bp encoding a protein of 25 kDa) from
Enterobacter sp. which showed no similarity to any previously isolated genes reported to degrade organophosphates
was characterized by Chino-Flores, et al. [80]. Another gene, mpd, encoding an organophosphate degrading protein,
was isolated from a parathion-methyl degrading Plesiomonas sp. that showed no homology to the known opd genes
[14, 74] isolated Sphingomonas strain Dsp-2 having the ability to hydrolyze chlorpyrifos to TCP by the gene
encoding the chlorpyrifos hydrolytic enzyme with its greater hydrolytic efficiency than the wildtype mpd from
Plesiomonas sp. M6. mpd gene has also been reported to found in other genera of microbes. mpd gene located on the
chromosome of Stenotrophomonas sp. YC-1 was reported by Yang, et al. [44].
5. Genetically Engineered Bacteria Involved in Chloryrifos Biodegradation
Along with genes and enzymes, genetically engineered microorganisms made with gene and enzyme
engineering has become a rapidly growing and promising tool for degradation of various pollutants. Alteration in
specificity of MPH in Pseudomonas putida JS444 enhances the rate of chlorpyrifos degradation. For the first time,
MPH has been reported to display on the surface of microorganisms by using only N- and C-terminal domains of the
Ice Nucleation Protein (INPNC) from P. syringae INA5 as an anchoring motif. A shuttle vector pINCM coding for
INPNC–MPH was constructed and used to target MPH onto the surface of a Pseudomonas putida JS444 [81]. Cao,
6. Scientific Review
13
et al. [82] cloned a novel 6012 bp gene cluster from TCP-degrading strain P2 responsible for dehalogenation of TCP.
The gene cluster consisted of a monooxygenase gene (tcpA1), a flavin reductase gene (tcpB1), tcpR1, orf1 and orf2.
TcpA1 and TcpB1 worked together to catalyze the dehalogenation of three chlorine of TCP, and generated a more
readily biodegradable product of 3, 6-dihydroxypyridine-2, 5- dione. The cloning of mpd gene from chlorpyrifos
degrading bacterial strains to Escherichia coli helps in developing its biodegradation capability. Wang, et al. [83]
cloned Escherichia coli with opd gene that degrade chlorpyrifos co-metabolically. Yang, et al. [44] cloned the mpd
gene from chlorpyrifos degrading bacterium Stenotrophomonas sp. isolated using chlorpyrifos as the sole source of
carbon by enrichment method that degraded 100 mg/L of chlorpyrifos within 24h to DETP and TCP.
5.1. Immobilized Cells and Enzymes in Bioremediation
Various cells and enzymes are sensitive and unstable at extreme temperatures, in strong acids and alkaline
solutions and also in organic solvents. Besides, they can lose their ability to degrade substrates under certain
environmental stresses. Therefore, the immobilization of desired cells and enzymes on suitable materials as carriers
is gaining much consideration to extend the process of pollutant degradation. However, the information regarding to
the immobilization and characterization of enzymes that can degrade chlorpyrifos is limited [84]. Qiao, et al. [85]
reported immobilized cells of recombinant Escherichia coli can detoxify an aqueous waste stream containing the
insecticides, acetofenate and chlorpyrifos. An enhanced degradation of chlorpyrifos from 40.17% to 71.05% with the
immobilization of cells in mixed culture of Streptomyces sp. was reported by Fuentes, et al. [86]. Vijayalakshmi and
Usha [8] studied degradation of chlorpyrifos by free cells and calcium-alginate immobilized cells of Pseudomonas
putida isolated from an agricultural soil. Ca-alginate immobilized cells of Pseudomonas putida had higher
degradation efficiency of 96% for chlorpyrifos at 2% in comparison to 76% degradation by free cells. Wang, et al.
[87] found 70 % degradation rate of chlorpyrifos in soil after 48h of treatment with immobilized fungal laccase on
sodium alginate that was prepared by the method of embedding-crosslinking under different environmental
conditions. Xie, et al. [84] studied the free enzyme from Fusarium sp. LK. ex Fx and reported it is stable at 40°C.
However, after immobilization, the degrading enzyme was more stable at even higher temperatures of 50°C with
only a slight loss in its initial activity, even after three repeated uses.
6. Conclusion
In accompanied with other pesticides, various concerns regarding environmental pollution and human health
have been originated from the appliance of chlorpyrifos. Though a large number of microorganisms have been
isolated and characterized that can degrade and mineralize this compound, extensive research is going on for the co-
culturing of two or more microorganisms and development of efficient degradation pathways for chlorpyrifos.
Further studies on the genes, enzymes and immobilization responsible for enhanced biodegradation can be beneficial
in this regard. By integrating functional genomics, proteomics, transcriptomics and metabolomic data with
bioremediation process, a more exact system of microbial bioremediation is expected. Additionally, more research
on Omics-Based Approaches will enable us to detect even tiny amount of this anthropogenic compound.
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List of Figures
Fig-1. Chemical formula of chlorpyrifos
Fig-2. Effect of Chlorpyrifos on the AChE (Gilani et al., 2015)