Does pesticide exposure in the womb mean a lower IQ later on in life?
Three studies featured in the journal Environmental Health Perspectives seem to support that conclusion, although it's very difficult to rule out other factors that might give rise to this trend.
One longitudinal study focused on chlorpyrifos, an insecticide used to eradicate bugs in the house or on growing crops. Gradually, the product was phased out in 2000.
Direct exposure to the insecticide earlier in life is associated with neurological problems, but what about in the womb?
They found that an increase of the chemical in cord blood was associated with worse IQ levels and working memory at the age of 7.
Another study concluded that organophosphates, which are often used in food production, negatively affected children's IQ as early as 1 year of age. It's also worth noting that researchers suspect that moms' genes play a role in how damaging the chemical can be to developing babies.
A third study also focused on organophosphate pesticides by measuring compounds in mothers' urine during pregnancy. The concentration of compounds in the urine was associated with "poorer cognitive development" in children.
With this information, can we conclude that pesticide exposure in the womb - whether future mothers were exposed to chemicals by inhaling them or eating food covered with pesticides - gives rise to cognitive problems among youth?
As with other studies looking at the association between a specific cause and effect, it's nearly impossible to rule out other influences. Since it's both unethical and unlikely that children would be raised in a controlled lab environment, proving one way or another will be difficult to do.
On the other hand, it's obvious researchers are on to something. Their results advocate reducing exposure to pesticides - something we should strive for anyway, especially during pregnancy. The research may support establishing new standards to limit the amount of pesticides that industries and food producers are allowed to use. Exposure levels reported in these studies - which might be high enough to cause harm in children - still fit within the acceptable limits monitored by the U.S. Environmental Protection Agency.
Inhaling air from recently sprayed areas and consuming food not washed well from pesticide sprays can increase one's exposure to chemicals. This is why researchers suggest pregnant women avoid problematic chemicals and look into buying organic produce or consider better methods to wash foods thoroughly.
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