Pesticides are chemicals that destroy/repel pests. The use of pesticides is supposed to have beneficial effect on the production of crops. They are supposed to control the level of pest in the field but recently the issues of pesticide pollution is being seen. And the main reason behind this, is certainly the misuse of such chemical pesticides.

The problems with pesticides are:

1.      Evolution of Genetic resistance: The prolonged use of a particular pesticide can cause a pest population to develop genetic resistance to the pesticides. An insecticide that kills most of an insect population becomes less effective after prolong use. As a result, pesticides users switch to a new, often more expensive and to high doses and more frequently.

2.      Imbalances in the Ecosystem: When a pesticide is applied beside pests, beneficial insects are also killed which makes an organism more vulnerable to predators, diseases,or other environmental stresses and also kills natural enemies, predators.

New pest may evolved. Minor pest may changed into major pest. This is because the pesticide kills most of a certain pest’s natural predators, parasites, and competitors.

Example: Use of DDT (in lemon) resulted an outbreak of a scale insects. Brown plant hopper (in rice) in Nepal is also an example of pest resurgence.

3.      Persistence, Bioaccumulation, and Biological magnification: Chlorinated hydrocarbons are extremely persistent in the environment.Take many years to degrade, and when ingested stored in fatty tissues Bioaccumulation  is  the  movement  of  a  chemical from the surrounding   medium   into   an   organism. The primary   "sink"   for   some   pesticides  is  fatty tissue. Some pesticides, such as DDT, are "lipophilic",  meaning  that  they are soluble in,   and   accumulate  in,  fatty   tissue  such  as edible  fish tissue and human fatty tissue.Biomagnification  describes   the increasing concentration of a chemical as food energy   is    transformed    within   the food chain. Organisms at higher levels on food webs tend to have greater concentrations.

4.      Risks of pesticides to human health: Exposure to pesticides can damage human health. Exposure to short-term high levels can result even human death, whereas long-term exposure to low levels of pesticdes can cause certain types of cancer. Short-term Effects of pesticides are acute pesticide poisoning is a large-scale problem, especially in developing countries. In developing countries, users often use dangerous pesticides at higher dose and more frequently with minimum levels of safety precaution. WHO estimates that, globally, four million poisoning each year, and of these, about 300,000 die.

5.      Long-term effects of pesticides: Many pesticids are associated with carcinogenesis (creation of cancer),  immunotoxicity (affecting immune system), neurotoxicity (altering normal activity of nervous system), behavioral impairment , reproductive dysfunction, endocrine disruption, (affecting gland system), developmental disabilities, and respiratory diseases like asthma. Positive relationship between pesticide exposure and cancer (brain, breast, kidney, lung, pancreatic, stomach); leukemia,birth defects, low sperm counts,have been found. Chronic health effects are problemetic to study because most people are exposed to low doses of pesticides and delayed health effets are difficult to link to past exposure.

The simple solution to all this is the responsive use of pesticide according to the recommended dose. Along with this, the pesticides containers and bottles should be discarded into proper places.