Study Measures Effects of DDT in California Children
California infants exposed to the pesticide DDT in utero experienced mental and physical developmental delays, according to a study published in Pediatrics' July issue, the Los Angeles Times reports. The study is part of a larger effort by University of California-Berkeley researchers to measure the effect of agricultural chemicals on children in the Salinas Valley, an area with a high level of agriculture.
UC-Berkeley researchers measured pesticide levels in 360 pregnant women and tested their infants' mental and motor skills. Most of the women were born in Mexico, and all of the children were born in the Salinas Valley. The U.S. banned DDT in 1972, but Mexico permitted its use on farms until 2002 and for mosquito control until 2000.
The researchers found that for every tenfold increase in DDT exposure, the infants' mental development dropped two to three points. Researchers also observed a seven- to 10-point drop in the mental development of two-year-old children exposed to the highest levels of DDT in utero compared to infants who were not exposed.
The average mental score in the study was 86. Infants who score below 85 could potentially have learning disabilities.
Study authors plan to evaluate the same children until they reach school age because the tests did not indicate whether DDT effects were long-term. The study is the first to examine the effects of maternal levels of DDT, according to the Times (Cone, Los Angeles Times, 4/5).