• Cotton uses approximately 25% of the world’s insecticides and more than 10% of the pesticides (including herbicides, insecticides, and defoliants.).
• Cotton pesticides can enter the human food chain via cotton seed oil used in processed foods. The meat and dairy products from cows fed cottonseed meal, trash from cotton gins and cotton straw may also contain pesticides that were applied to cotton.
• Eighty-four million pounds of pesticides were sprayed on the 14.4 million acres of conventional cotton grown in the U.S. in 2000 (5.85 pounds/ acre), ranking cotton second behind corn in total amount of pesticides sprayed.
• Over 2.03 billion pounds of synthetic fertilizers were applied to conventional cotton the same year (142 pounds/acre), making cotton the fourth most heavily fertilized crop behind corn, winter wheat, and soybeans.
• The Environmental Protection Agency considers seven of the top 15 pesticides used on cotton in 2000 in the United States as “possible,” “likely,” “probable,” or “known” human carcinogens (acephate, dichloropropene, diuron, fluometuron, pendimethalin, tribufos, and trifluralin).
• It takes roughly one-third of a pound of chemicals (pesticides and fertilizers) to grow enough cotton for just one T-shirt.
  

In contrast, organic cotton has all the benefits of organic agriculture, in addition to providing stronger, healthier cotton. For now it costs a little more, but the benefits far outweigh the costs.

Source: The Sustainable Cotton Project