Child IQ loss linked to pesticides exposure in womb
The dangers to health from certain pesticides, for unborn children, has been shown to be very real, according to the latest results from a long-term study. Three separate papers published today in the journal Environmental Health Perspectives see significant declines in children's intelligence because of organophosphates (OPs) - specifically if their mothers had signs of higher exposure to those chemicals while they were developing in the womb.
That vindicates the long-held concerns about widespread use of such pesticides at home and in agriculture. It also reinforces the need for mothers to take care of what they eat during pregnancy - and to consider switching to organic food where possible.
Organophosphates are pesticides whose dangerous toxicity for the nervous system is well understood - after all, that is the reason why they are so effective when being used against agricultural and home pests. But because they break down quickly in the natural environment, scientists had presumed that the health effects for humans would be limited.
That assumption looks like being optimistic - recent reports have implicated OPs in higher levels of chronic fatigue syndrome, Alzheimer's and ADHD. Now this new study is showing a strong link between childhood intelligence, and the amount of OPs that mothers may have come across during pregnancy.
Over 300 children are being followed in the research project, which started in 1999. It is part of a long term look at a variety of pesticides being run by the University of California, and its Berkeley School of Public Health.
Mothers-to-be were tested for how much dialkyl phosphate (DAP) was present in their urine, for 2 sampling sessions during pregnancy. DAPs are produced by the body's processing of OPs that have been consumed, and so are a good indicator of OP exposure. The mental abilities of the children were then followed in the years following birth - together with regular testing for DAPs in the children themselves.
What the papers have found is that there is a strong correlation between a lower level of intelligence - both IQ and Wechsler Intelligence Scale measures - and in-womb exposure to Ops. For every ten-fold increase in a mother's DAP levels, there is a 5.5 drop in average IQ; similar results are seen in testing both city-dwelling children, and those in more rural areas.
Such a link wasn't found for those children who have had a high exposure to OPs since birth. That makes some sort of impairment in the developing nervous system and brains of unborn children, due to the absorbed organophosphates, as the most likely culprit.
The good news is that OP use is on a decline in many parts of the US. And for mothers-to-be, exposure to risky levels of OP can be reduced. The authors suggest not using pesticides around the home, thorough washing of fruit and vegetables - and best of all eating more organic food, which bans the use of such pesticides.
But it is important to keep eating fresh fruit and vegetables. Brenda Eskenaz, the study's principal investigator from Berkely, cautions ''Most people already are not getting enough fruits and vegetables in their diet, which is linked to serious health problems in the United States. People, especially those who are pregnant, need to eat a diet rich in fruits and vegetables.''