SapnaShudhodhanJamgade1, Deepak Tukaram Sakhare2, Papal Dilip Rathod1
- M.V.Sc Scholar, Department of Veterinary Pharmacology and Toxicology, Post Graduate Institute of Veterinary and Animal Sciences, Akola.
- Ph.D. Scholar, Division of Animal Biochemistry, Indian Veterinary Research Institute, Bareilly.
The United State Environmental Protection Agency (USEPA) defines pesticide as “any substance or mixture of substances intended for preventing, destroying, repelling or mitigating any pest”. As pesticides are the chemical, physical or biological agent that would kill or destroy unwanted plants or animals pest. Pesticides are one of the most widely used agrochemicals of toxicological importance. With the advent of the green revolution, the use of pesticides has increased many folds. Pesticide widely used to control insect vectors of public health importance. Pesticides consist of a large verity of chemical agents having diverse chemical structure and biological activities which form the largest group of potentially toxic agents which are intentionally introduced into the environment for protection against the pests of plant, plant, animal and human importance (Garg, 2006 and Sandhu, 2012).
- Classification of pesticide
There are three most popular ways of classifying pesticides; classification based on the mode of action, classification based on the targeted pest species and classification based on the chemical composition given in table-1 (Buchel, K. H. 1983).
- Impacts of pesticides use in agriculture and public health
The use of pesticides in agriculture has led to a significant improvement in crop yield per hectare of land. Many studies throughout the world have established a possible correlation relationship between the number of pesticides used per hectare and the number of crop yields per hectare. Pesticides like DDT and others proved their usefulness in agriculture and public health. Economies were boosted, crop yields were tremendously increased, and so were the decreases in fatalities from insect-borne diseases. Insecticides have saved the lives of countless millions of people from insect-borne diseases (Aktar, et. Al.,2009).
Table: 1.Classification of various pesticides
| Classification of pesticides | |||
| Sr no | Mode of action | Targeted pest species | Chemical composition of the pesticide |
| 1 | Contact (nonsystemic):Bring about the desired effect when they come in contact with the targeted pest. Ex.paraquat and diquatdibromide | Insecticides : Against Insects | Organochlorines: Ex. DDT, lindane, endosulfan, aldrin, dieldrin and chlordane |
| 2 | Systemic pesticides: Those which effectively penetrate the plant tissues and move through the plant vascular system in order to bring about the desired effect. Ex. 2, 4-D and glyphosate
|
Herbicides: Against weeds | Organophosphorous: Ex. parathion, malathion, diaznon and glyphosate |
| 3 | Rodenticides: Against Rodents | Carbamates: Ex. oxime and aryl carbamates | |
| 4 | Fungicides: Against Fungi | Pyrethrin and pyrethroids:
Ex.permethrin, cypermethrin and deltamethrin
|
|
| 5 | Acaricides and Miticides: Against Arachnids of the order Acarina such as ticks and Mites | ||
| 6 | Molluscicides: Against Mollusks | ||
- Side effects of pesticides used to the environment and public health
The primary benefits are improving productivity, Protection of crop losses/yield reduction, Vector disease control, Quality of food, and other areas – transport, sports complex, building. Rather than the good results of using pesticides in agriculture and public health described above, their use is accompanied by harmful, deleterious environmental and public health effects. Pesticides hold a unique position among environmental contaminants due to their high biological activity and toxicity (acute and chronic). Although some pesticides are to be selective in their modes of action, their selectivity is only limited to test animals. Thus pesticides can be best described as biocides (capable of harming all forms of life other than the target pest) (Sandhu, 2012).
- Direct impact on humans: Pesticide poisoning cause initial stimulation of CNS followed by depression and death due to respiratory failure. The behavioral changes like aggressiveness, wall climbing, abnormal posture, madness syndrome, initial anxiety and the neurological symptoms like hypersensitivity, hyperthermia, vomition, diarrhea, and micturition along with marked salivation are seen (Garg, 2006).
- Impact through food commodities: After their use agricultural and animal husbandry operations, pesticides enter into the food chain and ultimately affect man and animals and produced short and long term toxic effects. Persistent administration even in lower doses, may effect on body immune system which afterward leads to the certain irreversible toxic effect like carcinogenicity, teratogenicity and more susceptibility to various infection. (Aktar, et. Al., 2009).
- Impact on environment: Due to the specific effect of pesticides on the ecosystem, these chemicals are released into the environment. In addition, they adversely affect and interfere with the life of non-target organisms in the ecosystem
- Surface water contamination: The major sources of pesticide poisoning include accidental exposure of the most common source of pesticide poisoning and can result from the ingestion of pesticide sprayed crops, drinking of water from paddy fields treated with a pesticide may cause the death of livestock. Similarly, animals may get poisoned following ingestion of paddy straw orother fodder sprayed with insecticides.Pesticides also found in ground water in India, About 58% of drinking water samples drawn from various hand pumps and wells around Bhopal were contaminated with OrganoChlorine pesticides above the EPA standards.
- Soil contamination: Effect on soil fertility (beneficial soil microorganisms) Heavy treatment of soil with pesticides can cause populations of beneficial soil microorganisms to decline(Drum, C. 1980).
f.Contamination of air, soil, and non-target vegetation: Pesticide sprays can directly hit non-target vegetation, or can drift or volatilize from the treated area and contaminate air, soil, and non-target plants. Some pesticide drift occurs during every application, even from ground equipment
Conclusion
There is no specific treatment is available. Treatment is only symptomatic and supportive. Remove the source of poisoning at once. Administration of non-oily purgatives, activated charcoal, a small dose of atropine sulfate and calcium borogluconate, pentobarbital sodium may be tried.
Reference:
Garg,Satish K. 2006. Textbook of Veterinary Toxicology. 1st Ed. Cbs publishers & Distributors New delhi, Page no-147-150.
Sandhu, Harpal S and Brar, Rajinder S. 2012.Textbook of Veterinary Toxicology. 2nded. KalyaniPublishers.ludhiyana.Page no-178-188.
Drum, C. (1980). Soil Chemistry of Pesticides, PPG Industries, Inc. USA
Buchel, K. H. (1983). Chemistry of Pesticides, John Wiley & Sons, Inc. New York, USA
Aktar,Md. Wasim.,Sengupta,Dwaipayan and Chowdhury, Ashim. 2009.Impact of pesticides use in agriculture: their benefits and hazards.InterdiscipToxicol. 2(1): 1–12.
