Findings from industry-funded toxicity studies of the commonly used pesticide chlorpyrifos that showed the product had no effects on neurodevelopment may be biased, misleading, and inaccurate, according to a new study.
The study, published in Environmental Health, examined raw data from animal research sponsored by Dow Chemical Company on chlorpyrifos and the related substance chlorpyrifos-methyl and found evidence that the chemicals were associated with changes in brain dimension of animals at all dose levels tested, though the industry reports did not note this finding. The researchers also raised concerns that some of the dosages of the chemicals used in the studies were too low to have any impact on nursing pups.
“If all of this raw data had been scrutinized properly, it should have at least required further testing to see if these findings were abnormal,” Dr. Philippe Grandjean, senior author of the study and adjunct professor of environmental health at Harvard T.H. Chan School of Public Health, said in a November 16 article in Environmental Health News. “In our minds, their [Dow’s] data are not appropriate to prove that [chlorpyrifos] is not a neurotoxicant.”