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  2. SEMINAR BY GUIDED BY NAME – Bisnukanta Muduli Mr.Priyachandan Sahoo CLASS - +3 3rd Year Science Lecturer in Chemistry ROLL NO – 2002ACHEM162
  3. CONTENTS: What is Pesticide ? Classification Chemical or Synthetic Pesticides Benefits of Pesticides Hazards of Pesticides Alternative to Pesticides Biological Control Methods Bio-Pesticides Reference
  4. 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.
  5. 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
  6. 1.Insecticides :- These are pesticides which are used to destroy insects. These can be two types :- (a) Organic origin (b) Inorganic origin
  7. 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
  8. 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.
  9. 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.
  10. 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.
  11. 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.
  12.  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
  13. 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.
  14. 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.
  15. 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)
  16. • 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.
  17. Harmful impact of pesticide on environment and living beings :-
  18. 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.
  19. 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.
  20. 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.
  22. REFERENCES:- answers/item/chemical-safety- pesticides#:~:text=Pesticides%20are%20chemical%20comp ounds%20that,kill%20pests%20that%20damage%20crops. es/index.cfm pesticides