These powerful antioxidant compounds in foods help strengthen the body's defense systems. Both conventionally grown and organic grown fruits and vegetables are nutritious and healthy for us. Chemicals used don't change the nutritional value. It also depends on the season in which it is planted, the soil quality, the weather conditions in which it is exposed to - the amount of rain and sun, and how it's harvested, handled and stored prior to being in the store, and then eventually to us. Vegetables and fruits aren't the only foods that can contain pesticides.
Pesticides can also be present in meats and dairy products.
Organ meats like liver, high fat meats, and high fat dairy products have higher residue levels than low fat sources, since residues accumulate in the liver and fat of animals. Grains contain little residue since crops are often treated soon after planting, prior to the development of the edible plant parts. The physical processing of the grains also removes most residues. The Food Quality Protection Act of 1996 requires the EPA to reassess all existing tolerances over a 10-year period. The Food Quality Protection Act requires that a pesticide must be proven safe for infants and children before it is used on crops.