Pesticides are used to kill the crop invaders. These pesticides are sprayed on the crops where they remain. These crops are sold to the public and used in the production of animal feed and other byproducts.

The crops are the same ones we buy at market to eat. The bugs are gone but the chemicals are not. We are ingesting these chemicals which were used to kill living organisms. These chemicals reach the colon and remain there, making the colon toxic and slowly poisoning the body.  

the website 

http://www.globalhealingcenter.com/effects-of-pesticides/pesticides is quite useful