The research team, from Wake Forest University Baptist Medical Center, the Southwest Research Institute, and NIEHS, found pesticide residues on floors, toys and hands of children who lived in farm worker households in four mountain counties in North Carolina and two in Virginia. The team looked only at households with children under 7.
"Pesticides pose a greater health risk for children, because of their small body size and rapid development," said Sara A. Quandt, Ph.D., professor of public health sciences -- epidemiology and lead author.
"People have always said that no one has ever demonstrated that workers in North Carolina and Virginia are exposed to pesticides," she said. "Now we have."
Quandt said the team targeted eight agricultural chemicals and 13 pesticides commonly found in homes in the United States. They wiped toys to detect chemicals there, and used similar methods on children's hands and on the portions of the floor where they were likely to play. They sent the wipes to the Southwest Research Institute in San Antonio, Texas, for analysis.
Laboratory results showed residues of six agricultural chemicals and 11 residential pesticides. Quandt noted that others had found that pesticide residues can remain on surfaces indoors for long periods of time, "creating a significant exposure for children, especially those young enough to play on floors or to place toys and household objects in the mouth."
Adults in these farm worker households often apply chemicals and perform hand labor in fields treated with pesticides.