Environmental toxicology deals with the harmful impacts of pollutants on living organisms. Pollutants include chemicals present in the air, soil, and water due to human activity. More than 60,000 chemicals are in common use and pollution is increasing due to industrialization. Pollution can cause respiratory issues, central nervous system depression, and acute toxicity. Ecotoxicology examines the effects of pollutants on ecosystems and communities. Major types of pollution include water, air, and land pollution which can contaminate resources and spread disease. Chemical, biological, nuclear and radiological weapons can also harm humans through inhalation, ingestion and absorption.

1. Environmental Toxicology

9. Environmental Toxicology
• It deals with potentially harmful impact of chemicals present as
pollutants of the environment, to living organisms.
• Environment includes all the surroundings of living organisms,
especially the air, soil and water.
• A pollutant is a substance present in the environment due to human
activity, and which has harmful effect on living organisms.

10. • More than 60,000 chemicals are said to be in common use.
• With advances in technology, pollution is increasing.
• The main causes of pollution are the production and use of industrial
chemicals, increased use of insecticides, etc., in agriculture and
production and use of energy.

11. • All substances causing methemoglobinemia, and smoke inhalation can cause
upper airway obstruction, lower airway obstruction, bronchospasm, pulmonary
oedema and tissue hypoxia.
• Smoke may contain acrolein (aldehyde), ammonia, CO, cyanide, oxides of
nitrogen, hydrogen sulphide, sulphur dioxide, hydrogen chloride, chlorine,
phosphene, isocyanates, etc., depending on the material burnt.
• Acute respiratory failure may occur due to atelectasis, airway obstruction, or
pulmonary oedema.
• Toxic combustion products depress CNS by acting as anaesthetic agents.

12. Ecotoxicology
• It is concerned with the toxic effects of chemicals and physical agents
on living organisms, especially in pollutions and communities with in
defined ecosystems.
• It includes the transfer pathways of those agents and their interactions
with the environment.

13. POLLUTION
1. Water Pollution
Definition-Any chemicals, physical or biological change in the quality
of water that has a harmful effect on any living thing called as water
pollution.

14. Types of pollution of water
 Surface waters pollution
 Ground water pollution

15. Sources of water Pollution
 Sewage leakages
 Oil spillage
 Industrial waste dumped into waters
 Flooding during rainy season which carries waste deposits into our waters.
 Building lavatories and visionaries over running water
 House hold chemicals and animal wastes.
 Radioisotope, heavy metal, Pesticides etc.

16. General clinical manifestations of drinking of polluted water by
human being-
• Water has played a significant role in the transmission of human
diseases.
• Typhoid fever, diarrhoea, infectious hepatitis, bacillary and amoebic
dysenteries and many varieties of gastrointestinal diseases could be
transmitted by water.

17. 2. Air Pollution-
Definition- The presence or introduction of gases into the air which
has harmful or poisonous effects is called as air pollution.
Causes of air pollution
• Burning of fossil Fuels- Sulphur dioxide emitted from the
combustion of fossil fuels like coal, petroleum and other factory
combustibles is one of the major causes of air pollution.
• Pollution emitted from vehicles including trucks, jeeps, cars, trains,
airplanes cause immense amount of pollution.

18. • Agricultural activities: Ammonia is a very common by product from
agriculture related activities and is one of the most hazardous gases
in the atmosphere.
• Exhaust from factories and industries: Manufacturing industries
release large amount of carbon monoxide, hydrocarbons, organic
compounds, and chemicals into the air there by depleting the quality
of air.

19. • Mining operations: During the process dust and chemicals are
released in the air causing massive air pollution.
• Indoor air pollution: Household cleaning products, Painting supplies
emit toxic chemicals in the cause air pollution. Indoor air pollution
caused by combustion of solid fuels for cooking and domestic
heating in India.

20. Adverse health effects of indoor air pollution in India
• Acute lower respiratory tract infection in children less than 5 years of
age, COPD in women chronically exposed, Aggravation of Asthma
and COPD, ischemic heart disease, Tuberculosis, adverse pregnancy
outcome, Cataract, Lung cancer.
Adverse health effects of outdoor air pollution in India
• Outdoor pollution causes significant increase in death from
respiratory and cardiovascular.

21. 3.Land pollution-
Definition-The deposition of solid or liquid waste materials on land or
underground in a manner that can contaminate the soil and groundwater
which causes hazards to living called land pollution.

22. Causes and sources of Land pollution-
 Agricultural activities- Farmer often use Highly toxic fertilizers and pesticides to
get rid of insects, fungi and bacteria from their crops which caused land pollution.
 Mining activities: During extraction and mining activities, several land spaces are
created beneath the surface.
 Overcrowded landfills: Each household produces tonnes of garbage each year.
Garbage like aluminium, plastic, paper, cloth, wood, is collected and sent to the
local recycling unit.

23.  Effects of land pollution on human being:
 Cancer- Many of the widely used pesticides on agricultural lands are potentially
carcinogenic.
 Neurological Problem: According to the EPA, children are most vulnerable to the
health effects of lead in the soil. Their developing neurological systems put them
at risk for serious health issues, causing possible brain and nervous system
damage.
 Tissue Damage and irritation: Mercury can cause irritation of your internal and
external tissues, such as your skin and the lining of your gastrointestinal tract.
The severity depends upon the toxin and length of exposure

24. Solutions for land pollution:
 Make people aware about the concept of reduce, recycle and reuse.
 Reduce the use of pesticides and fertilizers in agricultural activities.
 Avoid buying packages items as they will lead to garbage and end up in landfill
site.
 Ensure that you do not litter on the ground and do proper disposal of garbage.
 Buy biodegradable products.
 Do organic gardening and eat organic food that will be grown without the use of
pesticides.
 Create dumping ground away from residential areas.

25. Effect of chemical and nuclear warfare
• Chemical weapons are chemical agents, whether gaseous, liquid, or
solid, those are employed because of their direct toxic effects on
humans, animals, and plants.
• They inflict damage when inhaled, absorbed through the skin, or
ingested in food or drink.
• Chemical agents become weapons when they are placed into artillery
shells, land mines, aerial bombs, missile warheads, mortar shells,
grenades, spray tanks, or any other means of delivering the agents to
designated targets.

26. Chemical used in war, their clinical feature & Management
S.
N.
Chemical Clinical Feature Management
1 Nerve
agents
Moderate Exposure: Diffuse muscle
cramping, runny nose, difficulty
breathing, eye pain, diminished vision,
sweating & muscle tremors.
High exposure : The above plus sudden
loss of consciousness, seizures, flaccid
paralysis (late sign)
Atropine (2 mg) iv; repeat q 5 minute, titrate until effective,
average doses 6 to >15 mg/IM in the field before IV access
(establish airway for oxygenation).
Pralidoxime chloride: (2-PAMCI) 600-1800 mg IM or 1.0 g IV
over 20-30 minutes (maximum 2g IM or IV per hour). Additional
doses of atropine and 2-PAMCI depending on severity. Diazepam
or lorazepam to prevent seizures.
2 Cyanides Moderate exposure:- Giddiness,
palpitation, Dizziness, nausea, vomiting,
headache, eye irritation, increase in rate
and depth of breathing (hyperventilation),
drowsiness.
High exposure: Immediate loss of
consciousness, convulsions and death
with in 1 to 5 minute.
100% oxygen by face mask; intubation with 100% Fio2 if
indicated amyl nitrite via inhalation. 1 ampule amyl nitrite via
inhalation, 1 ampule (0.2 mL) q 5 Minutes sodium nitrite (300
mg IV over 5-10 minutes) and sodium thiosulfate(12.5 g IV).
Additional sodium nitrite should be given based on haemoglobin
level and weight of patient.

27. Biological Warfare
Micro-
organism
Agent Disease Route
Bacteria Bacillus anthrasis Anthrax Aerosol Spores
Yersinia pestis Plague Aerosol Vegetative cells
Brucella abortus Brucellosis Aerosol Vegetative cells
B. Melitensis Brucellosis Aerosol Vegetative cells
Viruses Variola virus Small pox Aerosol Virus particle
Ebola viruses Ebola haemorrhagic fever Aerosol Virus particle
Marburg viruses Marburg haemorrhagic fever Aerosol Virus particle
Toxin Clostridium Botulinum Botulism Ingestion of food & water Toxin
Stephylococcus aureus Staphylococcus enterotoxin
type
Ingestion of food & water Toxin

28. Nuclear War &its effects
• Nuclear weapons are the most destructive weapons available for use
on the battlefield today.
• The principal physical effects of nuclear weapons are blast, thermal
radiation (heat), and nuclear radiation.
• These effects are dependent upon the yield (or size) of the weapon
expressed in kilotons (KT), physical design of the weapon (such as
conventional and enhanced), and upon the method of employment. For
a low altitude detonation of a moderate sized (3 to 10 KT) weapons,
the energy is distributed as follows:

29. Radiation effects on Humans:-
• The most important attributed factor responsible for damage is the
amount of the dose. The more energy absorbed by cells, the greater the
biological damage.
• Health physicists refer to the amount of energy absorbed by the body
as the radiation dose. The effects of exposure to high levels of
radioactive fall out include…..

30. S.N
.
Organ Damage
1. Hair Loss
2. Brain Radiation kills nerve cells and small blood vessels, and cause seizures and immediate
death.
3. Thyroid The thyroid gland is susceptible to radioactive iodine. In sufficient amounts,
radioactive iodine can destroy all or part of the thyroid. By taking potassium iodide
can reduce the effects of exposure.
4. Blood Bleeding from the month and gums, internal bleeding and the blood’s lymphocyte
cell count will be reduced, leaving the victim more susceptible to infection.
5. Heart Immediate damage to small blood vessels and probably cause heart failure and death
directly.
6. GIT Radiation damage to the intestinal tract lining will cause nausea, bloody vomiting and
diarrhoea.
7. Reproduc
tive
Long term, some radiation sickness victims will become sterile.