reporter: but pollen says new research studies show a new study between pesticide exposure and hyperactivity disorder in children. for a growing number of consumers that is a reason to buy organic or local and it was a $1 billion a year industry in 1990 is now more than $26 billion a year. organics cost more to cultivate and that high demand always adds to the price tag. so, when to spend your hard-earned money on organic food? foods that have a very delicate skin like grapes and strawberries and like peaches and like apples, that s a good investment. reporter: the nonprofit environmental working list has the dirty dozens. fruits and vegetables that carry high levels. save on the foods you peel, they generally have the lowest pesticide residue and pollen recommends organic dairy especially for pregnant women and kids.