Seminário Nacional do Benzeno ( 5 e 6 dez/12) - Derivação de Limites de Exposição Ocupacional para Substâncias Carcinogênicas e
Mutagênicas - Experiências Internacionais e Nacional
This document discusses occupational cancers and preventive strategies. It defines how carcinogens are identified and classified differently across countries. Approximately 2-8% of cancers are related to occupations, with certain chemicals and industries linked to increased risks of specific cancer types. Biomarkers can help assess exposure to known carcinogens like tobacco smoke and aflatoxin. The International Agency for Research on Cancer (IARC) classifies agents as Group 1 (carcinogenic to humans), Group 2A (probably carcinogenic), Group 2B (possibly carcinogenic) or Group 3 (unclassifiable) based on evidence from human and animal studies. Preventive measures include banning known carcinogens from industry and replacing them with safer substitutes when possible
2-8% of cancers are caused by occupational exposures. Certain occupations are associated with increased risks of specific cancers, such as lung cancer from asbestos, arsenic, chromium and nickel exposure. Prevention through controlling exposures, smoking cessation, and medical monitoring can help reduce cancer risks from the workplace. Epidemiological studies help identify occupational carcinogens and estimate cancer risks but have limitations like long latency periods and confounding factors.
Industrial and agricultural activities over the last 50 years have significantly increased the concentration of toxic pollutants in the environment such as PAHs, PCBs, chlorophenols, nitrophenols, and BTEX. Most of these substances are mutagenic and carcinogenic. Environmental pollution accounts for over 55% of all cancers according to the WHO. Carcinogens may be chemical, physical, or biological agents that can cause cancer. They may act as initiators that alter DNA or promoters that encourage uncontrolled cell growth. Cancer rates are expected to increase significantly in the coming decades due to rising environmental pollution.
Application of nanomaterials in lifescienceArun kumar
The document discusses the application of nanomaterials in life sciences. It begins with an introduction to nanomaterials, their properties, synthesis, and classification. It then discusses two key applications: drug delivery and biosensors. For drug delivery, it provides examples of using metal-organic frameworks for controlled drug release. For biosensors, it details the development of a graphene-nickel oxide nanocomposite for cholesterol detection with high sensitivity and selectivity. In conclusion, the document outlines the potential of nanotechnology to advance areas like targeted drug delivery and disease diagnostics.
Design and development of nanomaterials for biomolecular detection and cancer...Arun kumar
This document discusses the design and development of nanomaterials for biomolecular detection and cancer therapy. It describes using graphene-protamine conjugates for sensing heparin and graphene/NiO composites for cholesterol sensing. For cancer therapy, it outlines using NMOF/PEG conjugates for drug delivery and ROS therapy, NCTP conjugates for drug delivery and cancer senescence, and PAMAM/5-FU conjugates for targeting oncoproteins. The document examines nanomaterials for improved biomolecular detection and drug delivery for cancer treatment.
Integrating advances in exposure science and toxicity testing next stepsChristina Parmionova
Findings from the workshop are
detailed in this report; key outcomes
include the following:
• Advances in molecular technologies are enabling environmental epidemiology and toxicology to
identify the exposure-effect relationship at the cellular, organismal, and population levels.
• The success of these approaches hinges on the availability of biologically-relevant exposure
information that is rapidly evolving from improved measurement technologies, more targeted
biomonitoring studies, and applications of advanced informatics and computational tools.
• The exposome, defined as a lifetime of human environmental exposures including lifestyle
factors, was highlighted as a possible framework for guiding developments in exposure science.
• Stem cells offer great potential for the development of in vitro toxicity models that are relevant to
effects that can occur in humans; similarly, new imaging methods offer innovative approaches to
understand mechanisms of toxicity in in vitro models.
• Computational models are becoming increasingly sophisticated and advanced both in the
analysis of ‘omics’ data, such as high throughput methods, as well as in their predictive
capabilities, such as for biological system interactions and (quantitative) structure- activity
relationship [(Q)SAR] modeling.
• New informational tools, including the Toxicological Priority Index (ToxPi) and the Chemical
Screening Visualization Tool (CVST), can incorporate and transform multiple types of chemicalinformation into visual formats that facilitate chemical prioritization and identification of areas for
additional toxicity testing.
• Value of information (VOI) methods and other decision analysis tools provide an approach for
identifying those test protocols that offer the best value in terms of resource allocation.
• Effective communication about chemicals must include both risk and benefit information so that
all shareholders, including the public, are fully informed.
• Risk characterization is an analytical, deliberative, and decision-driven process; successful
characterization of risk for chemicals requires getting the science and the participation right as
well as getting the right science and the right participation.
• Stakeholders must be part of the risk assessment process to improve credibility and the utility of
the results; input, dialogue,
This document discusses occupational cancers and preventive strategies. It defines how carcinogens are identified and classified differently across countries. Approximately 2-8% of cancers are related to occupations, with certain chemicals and industries linked to increased risks of specific cancer types. Biomarkers can help assess exposure to known carcinogens like tobacco smoke and aflatoxin. The International Agency for Research on Cancer (IARC) classifies agents as Group 1 (carcinogenic to humans), Group 2A (probably carcinogenic), Group 2B (possibly carcinogenic) or Group 3 (unclassifiable) based on evidence from human and animal studies. Preventive measures include banning known carcinogens from industry and replacing them with safer substitutes when possible
2-8% of cancers are caused by occupational exposures. Certain occupations are associated with increased risks of specific cancers, such as lung cancer from asbestos, arsenic, chromium and nickel exposure. Prevention through controlling exposures, smoking cessation, and medical monitoring can help reduce cancer risks from the workplace. Epidemiological studies help identify occupational carcinogens and estimate cancer risks but have limitations like long latency periods and confounding factors.
Industrial and agricultural activities over the last 50 years have significantly increased the concentration of toxic pollutants in the environment such as PAHs, PCBs, chlorophenols, nitrophenols, and BTEX. Most of these substances are mutagenic and carcinogenic. Environmental pollution accounts for over 55% of all cancers according to the WHO. Carcinogens may be chemical, physical, or biological agents that can cause cancer. They may act as initiators that alter DNA or promoters that encourage uncontrolled cell growth. Cancer rates are expected to increase significantly in the coming decades due to rising environmental pollution.
Application of nanomaterials in lifescienceArun kumar
The document discusses the application of nanomaterials in life sciences. It begins with an introduction to nanomaterials, their properties, synthesis, and classification. It then discusses two key applications: drug delivery and biosensors. For drug delivery, it provides examples of using metal-organic frameworks for controlled drug release. For biosensors, it details the development of a graphene-nickel oxide nanocomposite for cholesterol detection with high sensitivity and selectivity. In conclusion, the document outlines the potential of nanotechnology to advance areas like targeted drug delivery and disease diagnostics.
Design and development of nanomaterials for biomolecular detection and cancer...Arun kumar
This document discusses the design and development of nanomaterials for biomolecular detection and cancer therapy. It describes using graphene-protamine conjugates for sensing heparin and graphene/NiO composites for cholesterol sensing. For cancer therapy, it outlines using NMOF/PEG conjugates for drug delivery and ROS therapy, NCTP conjugates for drug delivery and cancer senescence, and PAMAM/5-FU conjugates for targeting oncoproteins. The document examines nanomaterials for improved biomolecular detection and drug delivery for cancer treatment.
Integrating advances in exposure science and toxicity testing next stepsChristina Parmionova
Findings from the workshop are
detailed in this report; key outcomes
include the following:
• Advances in molecular technologies are enabling environmental epidemiology and toxicology to
identify the exposure-effect relationship at the cellular, organismal, and population levels.
• The success of these approaches hinges on the availability of biologically-relevant exposure
information that is rapidly evolving from improved measurement technologies, more targeted
biomonitoring studies, and applications of advanced informatics and computational tools.
• The exposome, defined as a lifetime of human environmental exposures including lifestyle
factors, was highlighted as a possible framework for guiding developments in exposure science.
• Stem cells offer great potential for the development of in vitro toxicity models that are relevant to
effects that can occur in humans; similarly, new imaging methods offer innovative approaches to
understand mechanisms of toxicity in in vitro models.
• Computational models are becoming increasingly sophisticated and advanced both in the
analysis of ‘omics’ data, such as high throughput methods, as well as in their predictive
capabilities, such as for biological system interactions and (quantitative) structure- activity
relationship [(Q)SAR] modeling.
• New informational tools, including the Toxicological Priority Index (ToxPi) and the Chemical
Screening Visualization Tool (CVST), can incorporate and transform multiple types of chemicalinformation into visual formats that facilitate chemical prioritization and identification of areas for
additional toxicity testing.
• Value of information (VOI) methods and other decision analysis tools provide an approach for
identifying those test protocols that offer the best value in terms of resource allocation.
• Effective communication about chemicals must include both risk and benefit information so that
all shareholders, including the public, are fully informed.
• Risk characterization is an analytical, deliberative, and decision-driven process; successful
characterization of risk for chemicals requires getting the science and the participation right as
well as getting the right science and the right participation.
• Stakeholders must be part of the risk assessment process to improve credibility and the utility of
the results; input, dialogue,
This document summarizes regulations and safety procedures for working with benzene. It outlines permissible exposure limits, regulated areas, health hazards like cancer risks, required monitoring, emergency response procedures, necessary personal protective equipment, medical surveillance, and signage requirements. The Windsor Consulting Group provides industrial hygiene and occupational health consulting, with offices in Washington, DC and New York.
Benzene is the simplest aromatic hydrocarbon, containing a six-carbon ring with alternating single and double bonds. Unlike other unsaturated hydrocarbons, benzene does not readily undergo addition reactions. The aromatic properties of benzene and related compounds were established through the work of numerous scientists in the 19th and early 20th centuries, including Hofmann, Kekulé, Thomson, Robinson, and Hückel. Friedel-Crafts reactions involve alkylating or acylating aromatic rings using a Lewis acid catalyst. Polycyclic aromatic hydrocarbons consist of multiple fused benzene rings and are common combustion byproducts and pollutants found in cigarette smoke, styrofoam, gasoline, and other sources
Benzene is an organic chemical compound composed of six carbon atoms joined in a ring with one hydrogen atom attached to each carbon atom. It is a natural component of crude oil and one of the simplest petrochemicals. Benzene is a colorless, highly flammable liquid with a sweet smell. It is mainly used as a precursor to make chemicals such as ethylbenzene and cumene, and is an important component of gasoline comprising a few percent of its mass. Exposure to benzene can occur through inhalation of vapors during activities like fueling vehicles or using household products containing benzene. Long-term exposure is linked to increased cancer risk and damage to reproductive organs.
The document discusses the properties and structure of benzene (C6H6). It explains that benzene is planar and has resonance structures with delocalized pi electrons. This delocalization contributes to benzene's unusual stability compared to other unsaturated hydrocarbons. The document also introduces Kekulé structures and describes how current models of benzene are based on resonance and electron delocalization rather than distinct single and double bonds. It discusses how benzene's properties satisfy criteria for aromaticity including being cyclic, planar, fully conjugated, and having 4n+2 pi electrons as per Hückel's rule.
Benzene is a colorless or light yellow liquid at room temperature that is the parent compound of aromatic compounds. It has 6 carbons in a trigonal planar ring with alternating single and double bonds and delocalized electrons through resonance. Benzene floats on water, has a sweet odor, and is flammable.
5 Production Methods of Benzene cyclic hydrocarbon first isolated by Faraday a natural component of crude oil can be produced using different methods Pyrolysis gasoline, coal tar, Catalytic Reforming, Toluene hydrodealkylation, Toluene disproportionation
Benzene is an organic chemical compound with the molecular formula C6H6. Benzene is a colorless and highly flammable liquid with a sweet smell and a relatively high melting point
This document summarizes a research study on the biodegradation of polystyrene foam by microorganisms found in a landfill in Thailand. Samples of microbes were taken from polystyrene foam and contaminated soil in the landfill. The microbes were cultured with polystyrene as the sole carbon source to identify those capable of degrading it. Analysis of the cultures over time found shifts in the dominant microbial species. Selected species were identified through molecular techniques as known aromatic compound degraders, including Herbaspirillum seropedicae and Ochrobactrum sp. Scanning electron microscopy was used to observe physical changes to polystyrene exposed to the cultures, indicating biodegradation
Benzene is an organic compound with the formula C6H6 that is a colorless, flammable liquid. It is a natural constituent of crude oil and is produced industrially from petroleum as well as through catalytic reforming, toluene hydrodealkylation, toluene disproportionation, and steam cracking. Benzene's structure involves delocalized pi bonding that contributes to its stability and defines its chemical properties. It is used mainly to produce other chemicals including styrene, phenol, cyclohexane, and naphthalene.
Benzene is a colorless liquid with a sweet odor that is found naturally in crude oil and gasoline. Michael Faraday first isolated benzene in 1825 from illuminating gas. Benzene's stability is due to its resonance structure containing alternating single and double bonds. The main electrophilic aromatic substitution reactions of benzene are halogenation, nitration, sulfonation, and Friedel-Crafts acylation and alkylation. Activating groups like -OH increase the rate of substitution at the ortho and para positions by increasing electron density on the ring, while deactivating groups like -NO2 direct substitution to the meta position. Alkylbenzene side chains can undergo halogenation and
This document summarizes biodegradation of various xenobiotics including hydrocarbons, plastics, and pesticides. It discusses that xenobiotics are man-made chemicals that do not occur naturally. Biodegradation is the breakdown of these substances by microorganisms. Various microbes can degrade hydrocarbons through aerobic and anaerobic pathways. Plastics are broken down through hydrolysis and further degraded by acidogenic, acetogenic, and methanogenic bacteria. Pesticides are degraded through methods like dehalogenation, deamination, and hydroxylation. The document provides examples of microbes and mechanisms involved in the biodegradation of these pollutants.
Mechanism of aerobic & an aerobic biodegradation07sudha
The document discusses the mechanisms of aerobic and anaerobic biodegradation. It explains that aerobic biodegradation breaks down organic contaminants using oxygen, while anaerobic biodegradation occurs without oxygen. The key stages of anaerobic biodegradation are hydrolysis, acidogenesis, acetogenesis, and methanogenesis. It also compares aerobic and anaerobic biodegradation, noting that aerobic is faster but anaerobic produces less waste. Various microorganisms involved in each process are also identified.
Benzene is a colorless, flammable liquid hydrocarbon with a characteristic odor that occurs naturally in fossil fuels. It has a six-carbon ring structure with alternating single and double bonds. Benzene undergoes electrophilic substitution reactions like nitration, sulfonation, and Friedel-Crafts alkylation and acylation. It also undergoes addition reactions through halogenation and hydrogenation, as well as oxidation. Benzene and its derivatives have many applications in daily products like plastics, rubbers, fibers, detergents, and pharmaceuticals.
What is The Meaning Of Biodegradation?
A biodegradable product can dissolve easily in the environment without destroying nature. It’s the opposite of plastic and Styrofoam, which harm the environment.
The meaning of biodegradation is breaking down of organic substances by the help of other living organisms such as bacteria and microbes.
History:
The first known use of the word in biological text was in 1961 when employed to describe the breakdown of material into the base components of carbon, hydrogen, and oxygen by microorganisms .
The document defines environmental pollution and describes its three main types: air, water, and soil pollution. It provides details on the causes and effects of each type of pollution. Air pollution is caused by emissions from vehicles, factories, and burning of fossil fuels, and can lead to acid rain, haze, health issues, and depletion of the ozone layer. Water pollution results from industrial waste, oil spills, and waste disposal in rivers and oceans, harming wildlife and spreading disease. Soil pollution is caused by industrial chemicals, mining, pesticides, and landfills, contaminating groundwater and reducing soil fertility.
The document discusses the benefits of exercise for both physical and mental health. It notes that regular exercise can reduce the risk of diseases like heart disease and diabetes, improve mood, and reduce feelings of stress and anxiety. The document recommends that adults get at least 150 minutes of moderate exercise or 75 minutes of vigorous exercise per week to gain these benefits.
Alternative and integrated testing strategiesEFSA EU
The document discusses alternative and integrated testing strategies for toxicity assessment. It describes the development of such strategies over time, from early proposals in 2002 for integrated testing schemes, to the current use of adverse outcome pathways (AOPs) and predictive toxicology approaches using cellular assays. Validation and regulatory acceptance of alternative methods has allowed reduction in animal testing, especially for skin and eye irritation/corrosion hazards.
This document discusses eliminating occupational cancer caused by chemical exposures. It provides estimates of the current cancer burden from past occupational exposures in the UK. Exposures to many known carcinogens like asbestos, silica, and diesel exhaust have significantly declined over time due to improved controls and safety practices. However, cancers like mesothelioma and lung cancer still result from earlier exposures. Priority carcinogens are identified that can be further addressed through continued exposure monitoring and prevention efforts from government, industry, and unions to one day reduce occupational cancer rates below a public health risk threshold.
Occupational exposure limits (OEL) to chemical agents APIs - Quantitative Ris...Azierta
The Occupational Exposure Limit (OEL) is defined as the airborne concentration of a substance (expressed as a weighted average in time for a working day of 8 hours/day and 40 hours/working week) under which it is believed that nearly all workers may be repeatedly exposed (day after day, over a working lifetime) without adverse health effects (ACGIH, 2006; DFG, 2005).
Occupational exposure limits (OELs) are a useful tool to prevent adverse effects on health when managing chemical substances.
On a European scale…
• Employers are legally obliged to provide a work environment that does not threaten the health of the workers (Chemical Agent Directive 98/24/EC and Framework Directive 89/391/EEC).
• Under Directive 89/391/EEC, OELs can be developed nationally, Indicative Occupational Exposure Limit Values (IOELVs).
This document summarizes regulations and safety procedures for working with benzene. It outlines permissible exposure limits, regulated areas, health hazards like cancer risks, required monitoring, emergency response procedures, necessary personal protective equipment, medical surveillance, and signage requirements. The Windsor Consulting Group provides industrial hygiene and occupational health consulting, with offices in Washington, DC and New York.
Benzene is the simplest aromatic hydrocarbon, containing a six-carbon ring with alternating single and double bonds. Unlike other unsaturated hydrocarbons, benzene does not readily undergo addition reactions. The aromatic properties of benzene and related compounds were established through the work of numerous scientists in the 19th and early 20th centuries, including Hofmann, Kekulé, Thomson, Robinson, and Hückel. Friedel-Crafts reactions involve alkylating or acylating aromatic rings using a Lewis acid catalyst. Polycyclic aromatic hydrocarbons consist of multiple fused benzene rings and are common combustion byproducts and pollutants found in cigarette smoke, styrofoam, gasoline, and other sources
Benzene is an organic chemical compound composed of six carbon atoms joined in a ring with one hydrogen atom attached to each carbon atom. It is a natural component of crude oil and one of the simplest petrochemicals. Benzene is a colorless, highly flammable liquid with a sweet smell. It is mainly used as a precursor to make chemicals such as ethylbenzene and cumene, and is an important component of gasoline comprising a few percent of its mass. Exposure to benzene can occur through inhalation of vapors during activities like fueling vehicles or using household products containing benzene. Long-term exposure is linked to increased cancer risk and damage to reproductive organs.
The document discusses the properties and structure of benzene (C6H6). It explains that benzene is planar and has resonance structures with delocalized pi electrons. This delocalization contributes to benzene's unusual stability compared to other unsaturated hydrocarbons. The document also introduces Kekulé structures and describes how current models of benzene are based on resonance and electron delocalization rather than distinct single and double bonds. It discusses how benzene's properties satisfy criteria for aromaticity including being cyclic, planar, fully conjugated, and having 4n+2 pi electrons as per Hückel's rule.
Benzene is a colorless or light yellow liquid at room temperature that is the parent compound of aromatic compounds. It has 6 carbons in a trigonal planar ring with alternating single and double bonds and delocalized electrons through resonance. Benzene floats on water, has a sweet odor, and is flammable.
5 Production Methods of Benzene cyclic hydrocarbon first isolated by Faraday a natural component of crude oil can be produced using different methods Pyrolysis gasoline, coal tar, Catalytic Reforming, Toluene hydrodealkylation, Toluene disproportionation
Benzene is an organic chemical compound with the molecular formula C6H6. Benzene is a colorless and highly flammable liquid with a sweet smell and a relatively high melting point
This document summarizes a research study on the biodegradation of polystyrene foam by microorganisms found in a landfill in Thailand. Samples of microbes were taken from polystyrene foam and contaminated soil in the landfill. The microbes were cultured with polystyrene as the sole carbon source to identify those capable of degrading it. Analysis of the cultures over time found shifts in the dominant microbial species. Selected species were identified through molecular techniques as known aromatic compound degraders, including Herbaspirillum seropedicae and Ochrobactrum sp. Scanning electron microscopy was used to observe physical changes to polystyrene exposed to the cultures, indicating biodegradation
Benzene is an organic compound with the formula C6H6 that is a colorless, flammable liquid. It is a natural constituent of crude oil and is produced industrially from petroleum as well as through catalytic reforming, toluene hydrodealkylation, toluene disproportionation, and steam cracking. Benzene's structure involves delocalized pi bonding that contributes to its stability and defines its chemical properties. It is used mainly to produce other chemicals including styrene, phenol, cyclohexane, and naphthalene.
Benzene is a colorless liquid with a sweet odor that is found naturally in crude oil and gasoline. Michael Faraday first isolated benzene in 1825 from illuminating gas. Benzene's stability is due to its resonance structure containing alternating single and double bonds. The main electrophilic aromatic substitution reactions of benzene are halogenation, nitration, sulfonation, and Friedel-Crafts acylation and alkylation. Activating groups like -OH increase the rate of substitution at the ortho and para positions by increasing electron density on the ring, while deactivating groups like -NO2 direct substitution to the meta position. Alkylbenzene side chains can undergo halogenation and
This document summarizes biodegradation of various xenobiotics including hydrocarbons, plastics, and pesticides. It discusses that xenobiotics are man-made chemicals that do not occur naturally. Biodegradation is the breakdown of these substances by microorganisms. Various microbes can degrade hydrocarbons through aerobic and anaerobic pathways. Plastics are broken down through hydrolysis and further degraded by acidogenic, acetogenic, and methanogenic bacteria. Pesticides are degraded through methods like dehalogenation, deamination, and hydroxylation. The document provides examples of microbes and mechanisms involved in the biodegradation of these pollutants.
Mechanism of aerobic & an aerobic biodegradation07sudha
The document discusses the mechanisms of aerobic and anaerobic biodegradation. It explains that aerobic biodegradation breaks down organic contaminants using oxygen, while anaerobic biodegradation occurs without oxygen. The key stages of anaerobic biodegradation are hydrolysis, acidogenesis, acetogenesis, and methanogenesis. It also compares aerobic and anaerobic biodegradation, noting that aerobic is faster but anaerobic produces less waste. Various microorganisms involved in each process are also identified.
Benzene is a colorless, flammable liquid hydrocarbon with a characteristic odor that occurs naturally in fossil fuels. It has a six-carbon ring structure with alternating single and double bonds. Benzene undergoes electrophilic substitution reactions like nitration, sulfonation, and Friedel-Crafts alkylation and acylation. It also undergoes addition reactions through halogenation and hydrogenation, as well as oxidation. Benzene and its derivatives have many applications in daily products like plastics, rubbers, fibers, detergents, and pharmaceuticals.
What is The Meaning Of Biodegradation?
A biodegradable product can dissolve easily in the environment without destroying nature. It’s the opposite of plastic and Styrofoam, which harm the environment.
The meaning of biodegradation is breaking down of organic substances by the help of other living organisms such as bacteria and microbes.
History:
The first known use of the word in biological text was in 1961 when employed to describe the breakdown of material into the base components of carbon, hydrogen, and oxygen by microorganisms .
The document defines environmental pollution and describes its three main types: air, water, and soil pollution. It provides details on the causes and effects of each type of pollution. Air pollution is caused by emissions from vehicles, factories, and burning of fossil fuels, and can lead to acid rain, haze, health issues, and depletion of the ozone layer. Water pollution results from industrial waste, oil spills, and waste disposal in rivers and oceans, harming wildlife and spreading disease. Soil pollution is caused by industrial chemicals, mining, pesticides, and landfills, contaminating groundwater and reducing soil fertility.
The document discusses the benefits of exercise for both physical and mental health. It notes that regular exercise can reduce the risk of diseases like heart disease and diabetes, improve mood, and reduce feelings of stress and anxiety. The document recommends that adults get at least 150 minutes of moderate exercise or 75 minutes of vigorous exercise per week to gain these benefits.
Alternative and integrated testing strategiesEFSA EU
The document discusses alternative and integrated testing strategies for toxicity assessment. It describes the development of such strategies over time, from early proposals in 2002 for integrated testing schemes, to the current use of adverse outcome pathways (AOPs) and predictive toxicology approaches using cellular assays. Validation and regulatory acceptance of alternative methods has allowed reduction in animal testing, especially for skin and eye irritation/corrosion hazards.
This document discusses eliminating occupational cancer caused by chemical exposures. It provides estimates of the current cancer burden from past occupational exposures in the UK. Exposures to many known carcinogens like asbestos, silica, and diesel exhaust have significantly declined over time due to improved controls and safety practices. However, cancers like mesothelioma and lung cancer still result from earlier exposures. Priority carcinogens are identified that can be further addressed through continued exposure monitoring and prevention efforts from government, industry, and unions to one day reduce occupational cancer rates below a public health risk threshold.
Occupational exposure limits (OEL) to chemical agents APIs - Quantitative Ris...Azierta
The Occupational Exposure Limit (OEL) is defined as the airborne concentration of a substance (expressed as a weighted average in time for a working day of 8 hours/day and 40 hours/working week) under which it is believed that nearly all workers may be repeatedly exposed (day after day, over a working lifetime) without adverse health effects (ACGIH, 2006; DFG, 2005).
Occupational exposure limits (OELs) are a useful tool to prevent adverse effects on health when managing chemical substances.
On a European scale…
• Employers are legally obliged to provide a work environment that does not threaten the health of the workers (Chemical Agent Directive 98/24/EC and Framework Directive 89/391/EEC).
• Under Directive 89/391/EEC, OELs can be developed nationally, Indicative Occupational Exposure Limit Values (IOELVs).
Updating the european carcinogens directiveRetired
This document discusses occupational cancer risks and the European Carcinogens Directive. It summarizes a study that found increased mortality from cancers like lung cancer and bladder cancer in workers exposed to carcinogens at a coal plant. The directive aims to prevent risks from carcinogen exposure, but its requirements need updating. An estimated 5.3% of cancers in men are attributable to occupational exposure. Exposures have decreased over time but the cancer burden is still high. Updating exposure limits for substances like crystalline silica could significantly reduce future cancer cases and costs.
Dr. Igor V. Tetko introduces chemoinformatics, which uses informatics methods to solve chemical problems. It involves organizing and analyzing large chemical datasets. Key applications include drug discovery, chemical safety assessments like REACH, and predictive toxicology. Chemoinformatics helps address issues like high drug development costs and testing requirements by predicting properties in silico. The course covers topics like molecular representations, modeling techniques, and the online OCHEM database and modeling platform. Chemoinformatics aims to transform chemical data into knowledge to make better informed decisions.
Genotoxic impurities are potentially harmful compounds that must be strictly controlled in pharmaceuticals. They can cause mutations in DNA that may lead to cancer. Guidelines classify genotoxic impurities into five categories based on their mutagenic and carcinogenic potential to determine appropriate testing and control strategies. Analytical methods for detecting genotoxic impurities at the parts-per-million level or lower require sensitive techniques like mass spectrometry and NMR due to the stringent limits for these compounds.
Presentation from Manolis Kogevinas, Head of the Cancer Programme at ISGlobal, on occupational cancer.
Epidemiology in Occupational Health Conference - EPICOH 2017
This document outlines a lecture on occupational cancer. It begins with definitions of cancer and occupational cancer. It then discusses the global and national burden of cancer, noting that over 5 million new cancer cases occur worldwide annually and occupational exposures are responsible for 2-10% of cancer cases. The lecture covers carcinogenesis principles, strategies for identifying occupational carcinogens like epidemiological studies and toxicity testing, classes of carcinogens from IARC, and primary prevention methods like eliminating exposures and using protective equipment. It raises challenges around occupational cancer research and prevention.
This document derives Biomonitoring Equivalents (BEs) for triclosan based on recent health risk assessments and pharmacokinetic data. BEs provide screening values to evaluate biomonitoring data in a health risk context. The US EPA, EC, and Australian risk assessments identified no-observed-adverse-effect levels and reference doses for triclosan. Based on human and animal pharmacokinetic studies, the document estimates BE values in urine and plasma corresponding to the exposure guidelines. The urinary BEs were 6.4 and 2.6 mg/L, and the plasma BEs were 0.3, 0.9, and 0.4 mg/L corresponding to the different risk
The document discusses medical and laboratory waste management. It defines infectious waste and outlines various types of waste generated from medical facilities. Key elements of infectious waste management are identified, including identification, segregation, packaging, storage, transport, treatment, and disposal. Common treatment methods like incineration are described. The importance of microbial inactivation testing to ensure treatment effectiveness is emphasized. Guidelines for acceptable levels of pathogen reduction are provided. The document concludes with recommendations around improving waste treatment guidelines and prioritizing occupational health and safety in medical waste management.
The document discusses the challenges of achieving a non-toxic environment and proposes key actions to develop a more sustainable chemicals policy. It notes that while regulations aim to keep chemical concentrations below toxic levels, biodiversity continues to decline and human exposures are rising. It argues for intensifying efforts like minimizing chemical releases, banning persistent chemicals, increasing green chemistry and monitoring. The goal is to ultimately reduce both ecological damage and human health impacts from chemicals in the environment.
This article critically appraises the threshold of toxicity model for non-carcinogens. It presents five examples of non-carcinogens that appear to lack a threshold: neonicotinoid insecticides, dioxin, dieldrin, endocrine disruptors, and sulfhydryl-reactive metals. The toxicity of neonicotinoids matches the dose-response relationship of the carcinogen diethylnitrosamine. Recent evidence also shows neonicotinoids persist in the environment and accumulate over time in invertebrates, threatening their survival. Given examples like these where the dose-response curve is linear at low doses, risk assessments can no longer assume thresholds for non-carcinogens.
This document discusses diesel emissions and their health effects. It summarizes recent studies that found strong evidence of a link between diesel exhaust exposure and increased lung cancer risk among miners and truck drivers. Even relatively low exposures of 0.1 mg/m3 per year for 10 years were found to more than double lung cancer risk. The document also outlines strategies for measuring and controlling diesel particulate matter exposure to protect worker health.
what are EDCs, impacts/effects of EDCs, Sources, treatment of EDC by various methods such as activated carbon, phytoremediation, membrane fouling during ultrafiltration, constructed wetlands, the advanced oxidation process
Choosing Chemicals for Precautionary Regulation: A Filter Series Approach (2005)morosini1952
Ulrich Müller-Herold, Marco Morosini, Olivier Schucht
Abstract
The present case study develops and applies a systematic
approach to the precautionary pre-screening of xenobiotic
organic chemicals with respect to large-scale environmental
threats. It starts from scenarios for uncontrollable harm
and identifies conditions for their occurrence that then are
related to a set of amplifying factors, such as characteristic
isotropic spatial range F. The amplifying factors related
to a particular scenario are combined in a pre-screening
filter. It is the amplifying factors that can transform a potential
local damage into a large-scale threat. Controlling the
amplifying factors means controlling the scope and range
of the potential for damage. The threshold levels for the
amplifying factors of each filter are fixed through recourse
to historical and present-day reference chemicals so as
to filter out as many as possible of the currently regulated
environmental chemicals and to allow the economically
important compounds that pose no large-scale environmental
concern. The totality of filters, with each filter corresponding
to a particular threat scenario, provides the filter series
to be used in precautionary regulation. As a demonstration,
the filter series is then applied to a group of nonreferential
chemicals. The case study suggests that the filter
series approach may serve as a starting point for
precautionary assessment as a scientific method of its
own.
Introduction: Carbon Monoxide (CO) is a colourless, odourless and euphoric gas produced as a result of incomplete combustion of organic materials. It could either cause morbidity or mortality depending on the concentration and duration of exposure. Aim: The aim of this study was to examine the long term effect of CO inhalation on haematological parameters.
This study summarizes a population-based study conducted approximately 20 years after a TCDD exposure accident in Seveso, Italy to evaluate long-term effects on immune and dioxin response biomarkers. The study randomly selected 121 subjects from the most exposed zones and a non-exposed area, measuring their plasma TCDD levels and markers of the aryl-hydrocarbon receptor pathway. Plasma TCDD levels ranged from background to 90 ng/kg and were associated with decreased plasma IgG concentrations and aryl-hydrocarbon receptor mRNA levels in lymphocytes. When lymphocytes were cultured with TCDD, genes in the aryl-hydrocarbon receptor pathway were induced, and plasma TCDD associated with decreased enzyme activity. The findings suggest long
The document discusses the potential applications of nanotechnology for site remediation. It describes how nanomaterials like nanoparticles and nanoscale zeolites could be used to detect, filter, and break down environmental contaminants more efficiently. The document outlines EPA research on using nanotechnology to address challenges in green manufacturing, contamination cleanup, and waste treatment. It also provides examples of how nanomaterials like thiol-functionalized nanoparticles and swellable organosilica are being tested and applied to remediate mercury, volatile organic compounds, and other pollutants in soils and water.
Este documento fornece dados estatísticos sobre o mercado de trabalho no Brasil e em seus estados e subsetores industriais. Inclui informações sobre a população, emprego formal, evolução do saldo de empregos na indústria e construção civil no Brasil entre 2008-2012. Também fornece dados detalhados sobre emprego por estado, incluindo participação da população em carteira assinada.
101 propostas para modernização trabalhista - www.relacoesdotrabalho.com.brradarrt
Este documento apresenta 101 propostas para a modernização da legislação trabalhista brasileira. As propostas buscam promover maior flexibilidade nas relações de trabalho, reduzir custos para as empresas e incentivar a geração de empregos. Dentre as propostas, destacam-se a valorização da negociação coletiva, a flexibilização de jornadas de trabalho, incentivos à contratação de determinados grupos e a redução de encargos para as empresas. O documento também traz propostas relacionadas à saúde e segurança do trabalhador, benefí
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O documento consolida a legislação brasileira sobre o benzeno, incluindo o Acordo Nacional do Benzeno de 1994, normas regulamentadoras, portarias e instruções normativas sobre limites de exposição, monitoramento ambiental e da saúde de trabalhadores, cadastramento de empresas, transporte e comercialização de produtos. Também apresenta convenções e recomendações da Organização Internacional do Trabalho sobre benzeno e limites de exposição adotados em outros países.
O documento resume as discussões de um seminário nacional sobre o benzeno, incluindo: 1) Diferentes modelos internacionais para definir limites de exposição ocupacional a carcinógenos; 2) A importância dos mecanismos de ação e dados epidemiológicos nisso; 3) Estudos sobre a incidência de leucemia no Brasil e a associação com exposição ao benzeno. Recomenda-se formar um comitê para estabelecer limites de exposição nacionais e medir concentrações de benzeno em
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Seminário Nacional do Benzeno (5 e 6 de dez/12) - Derivação de Limites de Exposição Ocupacional para Substâncias Carcinogênicas e
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Mutagênicas - Experiências Internacionais e Nacional
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Mutagênicas - Experiências Internacionais e Nacional
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04062024_First India Newspaper Jaipur.pdfFIRST INDIA
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2. Derivation of OELs for carcinogens and mutagens
Strategy regarding carcinogens/mutagens of the
Scientific Committee on Occupatinal Exposure Limits
(SCOEL) of the European Union, with a view on benzene
Hermann M. Bolt, Dortmund/Germany
Leibniz-Institut für Arbeitsforschung an der TU Dortmund
Leibniz Research Centre for Working Environment and Human Factors
WHO Collaborating Centre
for Occupational Health
3. The Positioning of Advisory Bodies
The general discourse and interplays leading to OEL/BLV
regulations are similar at national and EU levels :
Political Legislation on
authorities occupational standards
Scientific experts
Social partners:
employers/industry,
trade unions
4. Chemical desasters with long-term influence on policy
and legislation on chemicals in the EU
1974 Flixborough/UK Cyclohexane explosion: 28 deaths,89 wounded
1976 Seveso/I TCDD desaster
1984 Bhopal/IND Methylisocyanate desaster
1986 Schweizerhalle/CH Environmental desaster; Rhine pollution
1993 Frankfurt-Höchst/D Accidents: communication desaster
2000 Baia Mare/RO Cyanide (50-100 t) in Tisa and Danube
2000 Enschede/NL Explosion: 23 deaths, 947 wounded
2001 Toulouse/F Ammonium nitrate explosion: 31 deaths
http://www.sust-chem.ethz.ch/teaching/courses/MaterialCuG/Unfaelle.pdf (modified)
5. OELs and BLVs: Development of the SCOEL Mandate
2013: New mandate
1980 1988 1989 1990 1995 1997 2004
SCOEL strategy
2007
for carcinogens
Revision/extension of
„Biological Monitoring“
EUR 19253“Methodology of derivation of OELs“
Commission Decision 95/320/EC setting up SCOEL
Council Directive 90/394/EEC protection of workers to carcinogens
Council Directive 89/391/EEC introduction of measures/safety and health
of workers
Council Directive 88/642/EEC amending the Directive of 1980
Council Directive 80/1107/EEC protection of workers from the risk related to exposure
to chemical, physical and biological agents at work
6. Commission Decision (95/320/EC) of 12 July 1995,
setting up a Scientific Committee for Occupational
Exposure Limits to Chemical Agents (SCOEL)
Article 2 (1)
... „The Committee shall in particular give advice on the setting of Occupational
Exposure Limits (OELs) based on scientific data and, where appropriate, shall
propose values which may include:
• the eight-hour time-weighted average (TWA),
• short-term limits/excursion limits (STEL),
• biological limit values.
The OELs may be supplemented, as appropriate, by further notations.
The Committee shall advise on any absorption of the substance in question
via other routes (such as skin and/or mucous membranes) which is likely
to occur.“ [Nota bene: no explicit reference to carcinogens!]
Review: European aspects of standard setting in
occupational hygiene and medicine. Rev.Environ.Health 16:81-86
7.
8. SCOEL Methodology (see SCOEL website)
✽ Evaluations on a “case by case“ basis
✽ Recommendations with clear justifications
✽ Critical effects and mechanisms of action to be
described as detailed as possible
✽ NOAEL and/or LOAEL, extrapolation model used
and quantitative considerations
✽ Systematic update of key scientific criteria (e.g.
genotoxicity)
8
9. Two kinds of OELs:
Indicative OELs
[majority of OELs]
Binding OELs
[traditionally for
genotoxic carcinogens
and for Pb]
10. Official performance data in 2008
(introduction of SCOEL carcinogen strategy)
✽ 156 Recommendations in total
✽ 18 Carcinogens
✽ 96 IOELVs (+10) D2000/39/CE & D2006/15/CE (91/322/CE)
• “Binding Values”: Benzene
VCM D 2004/37/CE Wood dust
Lead D 98/24/CE
Asbestos D2003/18/CE
10
12. Triggering Discussions for new Criteria (2000-2007)
(Threshold Effects for Carcinogens ?)
Induction of aneuploidy Endogenous carcinogens, within
Topoisomerase II poisons limits of homeostasis
Oxidative stress Clastogens (being discussed)
Inhibition of DNA synthesis
Steep dose-effect curve,
cytotoxicity involved
Kirsch-Volders et. al: Mutation Res. 464:3-11, 2000
Madle et. al: Mutation Res. 464:117-121, 2000
Pratt & Baron: Toxicol. Lett. 140/141: 53-62, 2003
„The dose-response relationship for a number of such
agents is generally accepted to show a threshold, however,
the degree of acceptance of the threshold effect differs in
different EU regulatory systems.“
13. Dose-Effect Relations in the Low Dose Range and Risk Evaluation
(Concept adopted by SCOEL - see Archives of Toxicology 82: 61-64, 2008)
Chemical carcinogen,
causing tumours in humans and/or experimental animals
Genotoxic Non-genotoxic
DNA reactive, Genotoxicity only on chromosome
causing mutations level (e.g. spindle, topoisomerase)
Clearly Weak genotoxin,
DNA-reactive Borderline secondary mecha-
& initiating cases nisms important
A: No threshold, B: Situation not clear C: Practical/apparent D: Perfect/statistical
LNT model to apply LNT as default threshold likely threshold likely
Numerical risk assessment, NOAEL
risk management procedures health-based exposure limits
14. Summary of the SCOEL Strategy for Carcinogens
• The scientific development allows to identify carcinogens
with a threshold-type mode of action. For these compounds
health based OELs (and BLVs, where appropriate) can be
derived.
• Such a mechanism-based assignment is independent of the
formal classification of carcinogens (i.e., former EU cate-
gories 1, 2 or 3, equivalent to GHS categories 1A, 1B, 2)!
• When derivation of a health-based OEL/BLV is not possible,
SCOEL assesses the quantitative cancer risk, whenever
data are sufficient.
• When data are not sufficient for a risk assessment, SCOEL
gives recommendations on possible strategies for risk
minimisation, if possible.
15. Results of SCOEL Discussions (Examples)
No threshold, LNT (Linear Non-Threshold) model to apply:
A vinyl chloride / vinyl bromide (risk assessment) MDA
dimethyl / diethyl sulfate 1,3-butadiene (risk assessment)
LNT as default assumption:
B acrylonitrile benzene (provisional assignment) arsenic
naphthalene hexavalent chromium o-anisidine
2,6-dimethylaniline (insuff. Data)
Practical/apparent threshold:
vinyl acetate nitrobenzene pyridine
C
lead (provisional OEL); lead chromate TRI DCM
glyceryl trinitrate
Perfect/statistical threshold:
D carbon tetrachloride chloroform
16. SCOEL: Formaldehyde - B oder C ?
Major points of general discussion
- Classical case since the 1980s of nasal tumours in rats
- Sublinear dose-response curve (accepted since the 1980s)
- Cytotoxicity as relevant/necessary influencing factor
- IARC (2005): Sufficient evidence of human nasopharyngeal
carcinomas (local effect in humans)
Discussions by SCOEL (2005-2007):
• A: Cell profiferation/irritation necessary for tumour formation
• B: No straightforward evidence for systemic effects
Group C: Carcinogen with practical threshold, OEL=0.2 ppm
17. Case Discussion: Vinyl Acetate, B oder C ?
- Local carcinogenesis upon inhalation and drinking water
application
- Locally hydrolysed to acetaldehyde and acetic acid
- Local genotoxicity of acetaldehyde plus cytotoxicity due to
acidification of cells (M. Bogdanffy, EUROTOX Budapest 2002)
Argumentations by SCOEL (2005)
• Cell proliferation/irritation necessary for tumour formation
• No straightforward evidence for systemic effects
Group C: OEL of 5 ppm recommended
18. Case: Acrylonitrile, B or C ?
- Carcinogenic to rats (oral and inhalation studies)
- Weakly mutagenic in vitro, but mutagenic epoxide metabolite
Argumentations for brain tumours discussed by SCOEL:
• Absence of DNA adducts in brain
• Oxidative DNA damage in astrocytes in vitro
• Reversible loss of gap junction communication in exposed astrocytes
• Dose-response curve sublinear
• Genotoxicity in vivo not straightforward
But: multi-organ carcinogen
[brain, spinal cord, Zymbal gland, GI tract (upon oral dosing),
mammary gland]
High acute toxicity, due to cyanide formation !
Group B; no health-based OEL
19. Special Case: Acrylamide, B or C ?
- Carcinogenic to rats (similar to acrylonitrile)
- Weakly mutagenic in vitro, but mutagenic epoxide metabolite
Argumentations discussed by SCOEL:
Similar to acrylonitrile: multi-organ carcinogen
[brain, mammary gland, mesotheliomas]
High neurotoxicity!
Group B; no health-based OEL
But: derivation of a „practical“ OEL and BLV, to
prevent neurotoxicity!
20. Case: Trichlorethylene, B oder C ?
- Renal cell carcinomas in humans exposed to very high peak
concentrations over several years (studies in Germany and France)
- -Lyase pathway involved in local bioactivation
- Specific VHL mutation patterns in highly exposed persons
- Nephrotoxicity involved ( 1-microglobulin, GST , other markers)
SCOEL Recommendation
Group C: Proposal of an OEL of 10 ppm
based on avoidance of nephrotoxicity
Toxicol. Lett. 140-141: 43-51, 2003
21. Further examples: Recent SCOEL
recommendations on inorganic compounds
A (no threshold): Cr(VI) - numerical risk assessment
B (situation not clear): Be – no OEL recommended
C (practical threshold):
• Crystalline silica, resp. dust: OEL = 50 µg/m3
• Cd: OEL = 4 µg/m3; BLV = 2 µg/g creatinine
• Ni: OEL = 10 µg/m3 inh., 5 µg/m3 resp. dust; BLV = 3 µg/L
D (perfect threshold): RCF; OEL = 0.3 fibres/mL
22. General conclusions:
There has been consistent progress in research on
modes of carcinogenic action. Secondary geno-
toxicity is receiving more attention!
The recognition of genotoxic and carcinogenic
thresholds will allow the assignment of health-based
limit values for an increasing number of relevant
carcinogens.
However: SCOEL/SEG discussions on benzene
dated prior to the introduction of the SCOEL
system for carcinogens!
23. SCOEL recommendation on benzene (I)
(1991, with addendum on biomonitoring 2006)
Benzene induces myelogenous leukemia
Growing evidence for lymphomas and multiple myelomas
Clastogenic in humans and animals,
with growig evidence for mutagenicity in vitro
Covalent binding of metabolites to DNA
-> No threshold can be identified at the present time
(equivalent to SCOEL Carcinogen Group B)
-> However: by lowering exposure risk can be reduced
24. SCOEL recommendation on benzene (II)
Risk assessment based on 1980s literature
Benzene Exposure Range of additional leuk.
conc. (ppm) ppm x years risk per 1000 workers
0.1 4 0.05 – 0.7
0.5 20 0.25 – 3.3
1.0 40 0.5 – 6.6
3.0 120 2.0 – 19.8
25. SCOEL recommendation on benzene (III)
An OEL of 0.5 ppm (20 ppm-years): reduction to 0.25-3.3
additional leukaemia cases per 1000
Non-genotoxic effects on the haematopoietic system
in animals: LOAEL 10 ppm
LOAEL for chromosomal damage (SCE, micronuclei) in
blood cells and bone marrow of rodents: 1-10 ppm
„If haematotoxic effects play a role in leukaemia induction,
avoidance of these will minimise leukaemia risk.
A limit value should be below 1.0 ppm;
this should also avoid chromosomal effects.“
26. Biological monitoring parameters (addendum 2006)
Benzene metabolism considered
t,t-Muconic acid
in urine
Benzene
in blood
S-Phenyl mercapturic acid
in urine
29. PS: Benzene may be a problem inside automobiles
Toxicol Lett. 2006; 160(2):93-104. Benzene and its methyl-derivatives:
derivation of maximum exposure levels in automobiles.
Schupp T, Bolt HM, Jaeck R, Hengstler JG.:
„A systematic toxicological evaluation of the risk associated
with benzene exposure in cars seems necessary.“
This keeps us busy.
Thank you for your attention!
30. Acknowledgement
Scientific Committee for
Occupational Exposure Limits,
DG Employment, European
Union, Luxembourg,
and the
German MAK Commission of
the Deutsche
Forschungsgemeinschaft (DFG)
La vallée des moulins (Müllerthal), Luxemburg