This certainly is interesting. I remember when I was a kid, the DDT truck used to spray our street and kids would run out to play in the fog:
Studies linking environmental substances to disease are coming fast and furious. Chemicals in plastics and common household goods have been associated with serious developmental problems, while a long inventory of other hazards are contributing to rising rates of modern ills: heart disease, obesity, diabetes, autism.
Add attention-deficit/hyperactivity disorder (ADHD) to the list. A new study in the journal Pediatrics associates exposure to pesticides to cases of ADHD in the U.S. and Canada. In the U.S. alone, an estimated 4.5 million children ages 5 to 17 have ever been diagnosed with ADHD, according to the Centers for Disease Control and Prevention, and rates of diagnosis have risen 3% a year between 1997 and 2006. Increasingly, research suggests that chemical influences, perhaps in combination with other environmental factors — like video gaming, hyperkinetically edited TV shows and flashing images in educational DVDs aimed at infants — may be contributing to the increase in attention problems.(See pictures of inside a school for autistic children.)
Led by Maryse Bouchard in Montreal, researchers based at the University of Montreal and Harvard University examined the potential relationship between ADHD and exposure to certain toxic pesticides called organophosphates. The team analyzed the levels of pesticide residues in the urine of more than 1,100 children aged 8 to 15 years old, and found that those with the highest levels of dialkyl phosphates, which are the breakdown products of organophosphate pesticides, also had the highest incidence of ADHD. Overall, they found a 35% increase in the odds of developing ADHD with every 10-fold increase in urinary concentration of the pesticide residues. The effect was seen even at the low end of exposure: kids who had any detectable, above-average level of the most common pesticide metabolite in their urine were twice as likely as those with undetectable levels to record symptoms of the learning disorder.
“I was quite surprised to see an effect at lower levels of exposure,” says Bouchard, who used data on ADHD from the National Health and Nutrition Examination Survey, a long-term study of health parameters of a representative sample of U.S. citizens.(Read how fidgeting can help kids with ADHD learn.)