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What happens when pesticides enter the body?

Most people are aware of the potential dangers of pesticide use.  However, understanding that pesticides can be harmful to human health is one thing; knowing how they work is another! 

1.  Most pesticides can enter the body through the skin, lungs or mouth.  If pesticides are eaten the muscular action of the esophagus carries them to the stomach. 2.  From the stomach, the pesticide enters the small intestine.  It then enters the blood through the villi of the small intestine.  Regardless of how a pesticide enters the body, it always winds up in the blood.
3.  Blood from the small intestine is carried to the liver.  Liver cells change the chemical nature of foreign chemicals, and this often has the effect of reducing the toxicity. These chemical reactions are called metabolism.  During metabolism the chemical structure of the pesticide is changed and the modified pesticide is then called a metabolite.

In the case of some pesticides, the process of metabolism actually causes a nontoxic pesticide to become a toxic metabolite.

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