Environmental effects Pesticide

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pesticide use raises number of environmental concerns. on 98% of sprayed insecticides , 95% of herbicides reach destination other target species, including non-target species, air, water , soil. pesticide drift occurs when pesticides suspended in air particles carried wind other areas, potentially contaminating them. pesticides 1 of causes of water pollution, , pesticides persistent organic pollutants , contribute soil contamination.


in addition, pesticide use reduces biodiversity, contributes pollinator decline, destroys habitat (especially birds), , threatens endangered species.

pests can develop resistance pesticide (pesticide resistance), necessitating new pesticide. alternatively greater dose of pesticide can used counteract resistance, although cause worsening of ambient pollution problem.


the stockholm convention on persistent organic pollutants, listed 9 of 12 dangerous , persistent organic chemicals (now obsolete) organochlorine pesticides. since chlorinated hydrocarbon pesticides dissolve in fats , not excreted, organisms tend retain them indefinitely. biological magnification process whereby these chlorinated hydrocarbons (pesticides) more concentrated @ each level of food chain. among marine animals, pesticide concentrations higher in carnivorous fishes, , more in fish-eating birds , mammals @ top of ecological pyramid. global distillation process whereby pesticides transported warmer colder regions of earth, in particular poles , mountain tops. pesticides evaporate atmosphere @ relatively high temperature can carried considerable distances (thousands of kilometers) wind area of lower temperature, condense , carried ground in rain or snow.


in order reduce negative impacts, desirable pesticides degradable or @ least deactivated in environment. such loss of activity or toxicity of pesticides due both innate chemical properties of compounds , environmental processes or conditions. example, presence of halogens within chemical structure slows down degradation in aerobic environment. adsorption soil may retard pesticide movement, may reduce bioavailability microbial degraders.








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