** FILE ** Crop dusting planes from Blair Air Service in Lemoore, Calif., dust cotton crops in this Tuesday, Sept. 25, 2001 file photo, in Lemoore. An Associated Press investigation has found that over the past decade, hundreds, possibly thousands, of schoolchildren in California and other agricultural states have been exposed to farm chemicals linked to sickness, brain damage and birth defects. The family of at least one California teenager suspects pesticides caused her death. (AP Photo/Gary Kazanjian, FILE)