TALCHER AUTONOMOUS COLLEGE,
TALCHER
DEPARTMENT OF CHEMISTRY
SESSION:- 2020 – 2023
SEMINAR ON:-
PESTICIDES

SEMINAR BY GUIDED BY
NAME – Bisnukanta Muduli Mr.Priyachandan Sahoo
CLASS - +3 3rd Year Science Lecturer in Chemistry
ROLL NO – 2002ACHEM162

CONTENTS:
What is Pesticide ?
Classification
Chemical or Synthetic Pesticides
Benefits of Pesticides
Hazards of Pesticides
Alternative to Pesticides
Biological Control Methods
Bio-Pesticides
Reference

PESTICIDES
A pesticide is a substance or mixture of
substance intended for preventing, destroying,
repelling or lessening the damage caused by
the pest.
A pest can be a insect, plant
pathogen, weed, bacteria etc. That
compete with the human for food, destroy
property, spread disease.
A pesticide can be a chemical, biological agent,
antimicrobial, disinfectant etc.
Many chemical pesticides are poisonous to
human and animals.

Classification :-
Pesticides are classified into classes depending on different
criteria.But some of the subclasses of pesticides are,
1.Insecticides
2.Herbicides
3.Fungicides
4.Rodenticides

1.Insecticides :-
These are pesticides which are used to destroy
insects.
These can be two types :-
(a) Organic origin
(b) Inorganic origin

Organic origin Insecticides:-
(a)Organic Insecticides:-
The Organic insecticides control and manage
insects in organic farming . These are stable to
light and heat.
Examples: D.D.T., Aldrin, etc.
(b) Phosphate Insecticides:-
These are very poisonous to insects.
These insecticides destroy harmful as well as
useful insects.
Examples:- Malathion,Parathion

Inorganic origin Insecticides :-
Inorganic insecticides are compounds that are not carbon based.
They are stable chemicals which do not evaporate and are
frequently soluble in water .These insecticides are not used in
modern production agriculture.
Examples:-
Fluorine compound in the form of sodium, calcium
and barium
flurosilicate (Na2SiF6,CaSiF6,BaSiF6)
Arsenic compound like arsenates of calcium and
lead.(Ca3(AsO4)2,Pb3(AsO4)2.

2. Herbicides:-
Pesticides which are used to destroy unwanted
weeds in the crop are called herbicides.
Selective herbicides kill specific weeds and
leaves the desired crop unharmed. Some Plant
are produce natural herbicides. Herbicides are
widely used in agriculture.
Example:-Napropamaide, Dacthal etc.

3. Fungicides :-
There are many fungi which are
responsible for producing plant
diseases. Chemical which destroy
such fungi are called fungicides.
Example: Bordeaux,Neem oil,Jojoba oil etc.

4.Rodenticides:-
• Rodenticides are pest control
chemical which are used to kill
rodents.
• Rodenticides are so dangerous that if
given in single feed bait , the rodents
is killed in first dose only.
Example-Bromadiolone, Chlorophacinone etc.

 Organochlorenes-These are non-biodegradable and persist in
Soil for long time e.g., DDT, BHC,Endosulfan, Aldrin.
 Organophosphate-These are esters of alcohols with
phosphoric acid or with some other acids.
These are very toxic acetyl-cholinesterase inhibitors as a
result of which the breakdown of acetyl choline stops.The
accumulation of acetyl choline resulting in convulsion
paralysis and death e.g.,Malathion.
 Carbamates- They are derived from carbamic acid. Mode
of action of carbamates is almost similar to organo-
phosphate e.g., Carbaryl, Dimetilan.
Chemical or Synthetic Pesticides

Benefits of pesticides
• They are used in public health programmes to
control vector born diseases
• They are used to protect the stored food grains.
• They protect the standing crop in the field. They
do not increase the crop yield like fertilizer but by
protecting the crop from pests.
• They can be used to control household pests.

Hazards of pesticides
1. The pesticide industries cause pollution of soil, water
and air. The pesticidal residue washed along with rain
water, is added to the nearby water resources making
it unfit for drinking.
2. They enter the food chain and cause problem of
bioaccumulation or biomagnification.
3. They are not target specific hence also kills non-pest
insects.
4. They are non-biodegradable and affect the balance of
ecosystem.

5.They are highly toxic in nature and if not handled
carefully, they can cause serious health problems like
cancer, deformities and disease.
6. Accidents in pesticides manufacturing units cause great
loss of human life e.g.,
Bhopal Gas Tragedy(India,1984)

• The worst industrial disaster in the history of
the world is related to pesticide production.
This Occurred at Union Carbide Factory in
Bhopal,India Dec. 3, 1984.
• In this incident, Methyl Isocyanide (MIC) – an
ingredient in the production of the
insecticide Carbaryl , escaped into the
atmosphere killing more than 3,000 people
within a few hour.
• The insecticide, Carbaryl, itself is a highly
toxic chemical and carcinogen (cancer
causing agent) to humans.
• The tragedy occurred due to lack of adequate
safeguards in the storing the chemicals and lack
of adequate warning to the public.
The Bhopal Gas Tragedy:-
(Top) Survivors of the tragedy
lineup outside the factory
awaiting treatment.

Harmful impact of pesticide on environment and living beings :-

Integrated pest management
• Integrated Pest Management (IPM)- is an
ecosystem based strategy that focus on long term
prevention of pests and practices to grow healthy
crops and minimise the use of pesticides.
• IPM programs use current, comprehensive
information on the life cycles of pests and their
interaction with the environment.

Biological control methods- It include the use of living
beneficial organisms, called natural enemies to control pests.
• Biological control is an important part of any integrated pest
management programme. All insect and mites have some
natural enemies.
• Managing these enemies can effectively control many pest.

Bio-Pesticides
• These are most effective, important and
commercially viable because these are
inexpensive, cause no pollution and pose no
threat to human health.
• It include naturally available agents in nature
e.g.-Viruses-Nuclear polyhedrosis virus
Bacteria-Bacillus thuringiensis
Fungi-Metarhizium, Beauveria
• It also includes the use of natural extracts
obtained from plants and microbes e.g.
Azadiractin from neem, Nicotine from
tobacco.

SAFETY CHECK

REFERENCES:-
https://www.who.int/news-room/questions-and-
answers/item/chemical-safety-
pesticides#:~:text=Pesticides%20are%20chemical%20comp
ounds%20that,kill%20pests%20that%20damage%20crops.
https://www.niehs.nih.gov/health/topics/agents/pesticid
es/index.cfm
https://en.wikipedia.org/wiki/Pesticide
https://www.epa.gov/safepestcontrol/why-we-use-
pesticides

THANK YOU