the food chain
chemical cycling through an ecosystem
Cotton is considered as the dirties crop as it requires many hazardous insecticides and pesticides that harm both human beings and animals while being cultivated. They also contaminate the groundwater through over-use of these chemicals. Cottonseed and field trash is used as animal feed. The pesticides affect the cows and their products.
through pesticides
One example is of a house fly that settles on any uncovered food in a kitchen, after walking on dog faeces out in the garden.
Extraction through fracking can contaminate groundwater
Rachel Carson's problem was the environmental damage caused by indiscriminate pesticide use, particularly DDT. She raised awareness about the harmful effects of pesticides on ecosystems and human health through her book "Silent Spring," which led to the eventual ban of DDT and sparked the modern environmental movement.
through organisms which contaminate food like house fly
contaminate
No, amoebic dysentery is not infectious. It is transmitted through contaminate food or water.
leaching
Well, they would have their own example of a problem and they would walk you through that problem. They probably won't help you cheat on algebra homework however, and the easiest source that can solve and walk you through a problem no questions asked is probably a very helpful math nerd or a clueless teacher. Or maybe you can pay for a tutor website or something.
There are thousands of types of Pesticides, some of organic and natural sources and some synthesized chemicals like paralytics. The word pollution could be subjective, Atmospheric Pollution - Possibly through pesticides delivery system, CFCs Water System Pollution - Possibly, in the case of DDT and birds for example Soil Pollution - Possibly, in the case of chemicals that are not soluble