IMPORTANT INFORMATION OF BIOCHEMISTRY ENVIRONMENTAL HAZARDS

1. BIOCHEMISTRY BASIS
OF ENVIROMENTAL
HEALTH HAZARDS

2. INTRODUCTION
WATER POLLUTION
METAL POISONING
PESTICIDE AND INSECTICIDE
AIR POLLUTION
NOISE POLLUTION

3. INTRODUCTION
Environmental pollution may be
regarded as the addition of
extraneous materials to air, water,
land which adversely affect the
quality of life.
Pollution may be caused by
physical , chemical and biological
processes.
Pollutants refers to a substance
which increase in quantity due to
human activity and adversely
affect the environment.

4. The pollution of water occur due to
the waste disposal from industries,
agriculture and municipalities.
The pollutants may be organic,
inorganic, sediment, radioactive and
thermal etc.
Several pathogenic organism find
there entry and causes disease.
The water borne disease includes
amoebiasis, infectious hepatitis,
cholera, thyroid.

6.  Lead is a most inorganic
pollutant found in air, water,
foods and soil.
The source of lead pollution
includes petrol, gasoline,
cigarettes, newspaper, lead pipes,
xerox copies.
Plasma concentration of >25
ug/dl in adults and 10 ug/dl in
children resulting toxic
manifestation.

7. The principal target organ of lead toxicity
is central nervous system.
In growing children, lead causes learning
disabilities and mental retardation.
In adults, it causes confusion, irritability,
abdominal colic and severe anemia.
Lead can pass through placenta and
causes miscarriage, stillbirth, and
premature birth.
SIGNS AND SYMPTOMS

8. Lead inhibit enzymes particularly
delta aminolevulinic acid
synthase and ALA dehyratase and
ferrochelatase of heme synthesis.
This results in severe anemia.
Calcium disodium versanate and
dimercaptosuccinic acid are used
as a antidote In lead poisoning.

9. It is a common industrial
pollutant. The source for
poisoning may be elemental,
organic or inorganic mercury.
Elemental mercury poisoning
causes oral lesions(stomatitis,
salivation), tremors ,
psychological changes(insomnia,
shyness, memory loss). This is
called erethism.

10. Organic mercury poisoning is
commonly referred to as
minimata disease by consuming
methyl mercury.
Methyl mercury causes
dysarthria, ataxia and visual field
constriction.
Dimercaprol derivatives and N-
acetylcysteine can increase the
excretion of mercury and are
useful in treatment.

11. Arsenic commonly found in many
insecticides and fungicides, is toxic to
the body.
There are certain regions in India
where arsenic is seen in water and
lead to chronic toxicity.
It act on sulfhydryl enzymes and
interfere with the cell metabolism.
It causes intravascular hemolysis,
which lead to the hemoglobinuria.

12. The source of aluminium includes
cooking vessels, building
materials, and cosmetics.
Aluminium precipitates
Alzheimer precursor proteins and
lead to Alzheimer’s disease.
Aluminium is implicated in
degeneration of dendrites. It is
involved in Parkinson’s disease.

13. Outbreak of cadmium toxicity
was reported in Japan in the form
of itai-itai or ouch disease.
Cadmium poisoning causes
fragile bone ,bone marrow
disorder, anemia and kidney
damage.
Biochemically cadmium replaces
zinc and adversely influences
several metabolic reaction.

14.  It is the widely used pesticide however continuous
use of DDT leads to its accumulation in foods
causing ill effects.
DDT being fat soluble accumulate in the adipose
tissue and is not excreted thus its concentration in
body goes on increasing.
DDT causes nervous irritability , muscle twitching
and convulsions.
DICHLORODIPHENYLTRICHLOROETHANE

15. Organophosphorus and
organocarbamates are the common
pesticides and organosulfurs
compound are fungicides.
They are powerful neurotoxic agent.
They inhibit acetylcholine esterase
through phosphorylation of active
centre of the enzyme.
Thus the nerve impulse across synapse
and at the neuromuscular junction is
prevented.
ORGANOPHOSPHORUS COMPOUND

16. The major constituent of air includes
nitrogen 78.09% and oxygen
20.94%carbon dioxide 0.03% and
water vapors.
The permissible level of total
suspended particle is 230 mg/cu.m.
The major constituent of air pollution
are SO₂, oxide of carbon, oxide of
nitrogen and hydrocarbon and
particulate.

17. Industrial activity such as burning of
fuel and oil emits large quantity of
sulphur dioxide.
It causes irritation of the respiratory
tract and increases air way resistance.
Dipalmityl lecithin, the phospholipid
acting as a lung surfactant get
affected.
Continuous exposure to SO₂ (>1ppm)
causes bronchitis and lung cancer.
It also causes acid rain.

18.  CO is produced by the incomplete
combustion of fuel and carbon containing
compound.
 CO combining with Hb to form carboxy Hb
this cause drastic reduction in the supply of
oxygen to tissue.
 At a CO concentration around 1ppm
impairment in mental performance and
visual perception take place.
 Death may be inevitable in person exposed
to above 750ppm of CO.

19. NO ₂ like carbon monooxide combine
with Hb and reduce supply of O₂ to
the tissue.
NO ₂ is more harmful to human health
than CO.
It causes cough, dyspnea, pulmonary
edema in acute manifestation.
In chronic manifestation causes
emphysema and chronic bronchitis

20. The solid dust particle suspended in
the atmosphere constitute particulate.
The source of particulate are grinding,
spraying, erosion and smoking etc.
Particulate causes interference in
respiratory function (coughing and
sneezing) and toxicity caused by
absorption of particulate chemicals.

21. The unwanted sound is noise ,which is
major urban environmental pollutant
Man can tolerate noise upto 100
decibel, a noise above 150 decibel is
uncomfortable.
It causes headache, increase blood
pressure, irritability, neuromuscular
tension, confusion , disturbed vision
and depression and loss of hearing.

22. Bibliography
DM Vasudevan
U Satyanarayana Chakrapani

23. THANK YOU