What a great question! This is a topic that I am very interested in.

I am a geologist and I study groundwater contamination. I study water because of the many human health impacts that occur because of contaminated water. One way that water can become contaminated is because of pesticides, but more often our intake of pesticides comes directly from the plants that they are sprayed on or from airborne drift in our environment when they are sprayed on fields or through animals which ingest the pesticides and then we eat those animals.

I first became interested in this topic after reading Rachel Carson's book 'Silent Spring' when I was in middle school, which is a collection of stories and explanations of cases where incorrect use of pesticides caused severe environmental damage and death to humans. I highly recommend this book. It is credited with helping to launch the environmental movement and has been named one of the most influential books of the last century.

Pesticides and insecticides are harmful chemicals meant to kill animals and plants. They can kill humans too if humans get large doses of them. Some pesticide substances collect in the fat cells of animals/humans that ingest them and stay there. There is a lot of research going on right now to explore the affects of pesticides on humans in small doses over time. While large doses are known to kill humans, there is not yet enough evidence to say exactly what small doses do. But as is the case with all poisons, its better not to put any in your body or your environment if possible.

There are many alternatives to pesticides. There are many organic and natural compounds that work to keep away pests that are not toxic to humans or as toxic. In addition, proper farming practices, especially those practiced on organic farms and on small farms where crops are rotated and planted among other plants, not of the same, type helps to control pests. There is always a way to control pests without poisons. This just takes more ingenuity and time which is why organic foods are more expensive. But in my opinion organic foods are worth every extra dollar. Also, many harmful pesticides that have been outlawed in the US are still being used in other countries and often there are spills and incorrect disposals which has killed many poor people working with these chemicals in industrial farms worldwide.

This is a big topic. I would direct you to Silent Spring or to Pesticide Action Network Website

On the PAN website, go under the 'resources' tab and then the 'Non pesticide Advisor' which will direct you to a lot of material on alternatives to pesticides and organic products you can purchase.