August 25, 2010

Pesticides linked to ADHD in children

Children exposed to pesticides known as organophosphates could have a higher risk of attention-deficit/hyperactivity disorder (ADHD), according to a U.S. study that urges parents to always wash produce thoroughly.

Researchers tracked the pesticides' breakdown products in childrens' urine and found those with high levels were almost twice as likely to develop ADHD as those with undetectable levels.

The findings are based on data from the general U.S. population, meaning that exposure to the pesticides could be harmful even at levels commonly found in children's environment.

Organophosphates were originally developed for chemical warfare, and they are known to be toxic to the nervous system.

There are about 40 organophosphate pesticides such as malathion registered in the United States, the researchers wrote in the journal Pediatrics.

The compounds have been linked to behavioral symptoms common to ADHD – for instance, impulsivity and attention problems – but exactly how is not fully understood.

Weisskopf and colleagues' sample included 1,139 children between 8 and 15 years. They interviewed the children's mothers, or another caretaker, and found that about one in 10 met the criteria for ADHD, which jibes with estimates for the general population.

After accounting for factors such as gender, age and race, they found the odds of having ADHD rose with the level of pesticide breakdown products.

For a 10–fold increase in one class of those compounds, the odds of ADHD increased by more than half. And for the most common breakdown product, called dimethyl triophosphate, the odds of ADHD almost doubled in kids with above–average levels compared to those without detectable levels.

If at all possible, eat organic fruits and vegetables. If that's not possible, be sure to wash them thouroughally before letting anyone eat them.