(Beyond Pesticides, July 31, 2007) Preliminary research into birth records and pesticide data reveal that mothers who were within 500 meters of fields sprayed with organochlorine pesticides during their first trimester of pregnancy were six times higher to have children with autism compared to mothers who did not live near the fields.
Scientists from the California Department of Public Health conducted the study, which is available online in Environmental Health and Perspectives, entitled, “Maternal Residence Near Agricultural Pesticide Applications and Autism Spectrum Disorders Among Children in the California Central Valley.” The study, initiated to “systemically explore the general hypothesis that residential proximity to agricultural pesticide applications during pregnancy could be associated with autism spectrum disorders in offspring,” found that 28% of the mothers studied who lived near fields in Central Valley, which were sprayed with organochlorines, such as endosulfan and dicofol, have children with autism. However, officials are quick to point out that their findings are preliminary.
“We want to emphasize that this is exploratory research,” says Dr. Mark Horton, M.D., director of the California Department of Health. “We have found very preliminary data that there may be an association. We are in no way concluding that there is a causal relationship between pesticide exposure of pregnant women and autism.”
The scientists conclude that the “possibility of a connection between gestational exposure to organochlorine pesticides and autism spectrum disorders requires further study.”
The study analyzes information collected for the years 1996 through 1998, for nearly 300,000 children born in 19 counties of the Sacramento and San Joaquin river valleys. State records of the addresses of the pregnant women were compared against those of fields sprayed with pesticides. Only areas sprayed with organochlorines exhibited extraordinary patterns.
The highest rates for children with autism were those whose mothers lived closest to these fields. Exposure is brought about due to chemicals drifting off of the fields and into residential areas.
According to Susan Kegley, Ph.D., of the Pesticide Action Network North America, “This is one of the first papers that links use of pesticide to incidence of a disease, and autism in particular. The findings are very strong. This is a six-fold factor in comparison to someone who is not exposed.” But even though small numbers of children were involved, “it is still one of those things that make you sit up and pay attention,” she says.
A previous report citing air monitoring in Fresno, Monterey and Tulare counties in July by the state Department of Pesticide Regulation indicates that endosulfan can spread via the air from fields and expose the public. The agency is likely to soon designate endosulfan as a toxic air contaminant, and then take suitable steps to minimize chemicals drifting off fields into nearby homes.
Endosulfan and dicofol were developed in the 1950s to kill mites on cotton, vegetables and other crops. Since then, organochlorine use has declined because of increasing insect resistance, coupled with use restrictions and phase-outs of most other organochlorines, such as DDT. Endosulfan and dicofol are still in use in the U.S., however, both affect the nervous system, and have been shown to cause reproductive effects and alter hormones in animal studies. Even though these chemicals are not found in household products, residues are also found in food.
A growing number of scientific studies now link exposure to pesticides with increased rates of certain cancers, nervous system diseases, learning disabilities, Parkinson’s disease, and reproductive problems. Children, especially, are considered a high-risk group due to their increased exposure and sensitivity to toxic chemicals. Developmental disabilities such as autism, attention deficit hyperactivity disorder, developmental delays, and behavioral disorders are being studied for links to childhood exposure and environmental contaminants found in pesticides. Autism, which has been increasing in prevalence, currently affects one in every 150 children.
For more information on pesticides and children’s health, and ways to protect the next generation, please visit http://www.beyondpesticides.org/schools/index.htm.
Source: Los Angeles Times