Pesticides linked to high risk of ADHD in children

Exposure to pesticides known as organophosphates may increase risk of attention-deficit/hyperactivity disorder or ADHD in children, a new study suggests.

Researchers tested urine samples from pediatric subjects and found that those with high levels of pesticides were about twice as likely to develop ADHD as those with undetected levels in their urine.

Marc Weisskopf of the Harvard School of Public Health, co-author of the study and colleagues published their study in the journal Pediatrics saying there are about 40 organophosphate pesticides allowed to be sold in the United States.

The study was based on data from the general U.S. population meaning that the findings are appplicable to the general population and children may be at high risk for ADHD if they are exposed to even low levels of these pesticides.

The toxicity of orthophosphates is well known. These chemicals are made originally as chemical weapons because they are toxic to the nervous system.

For the study, Weisskopf and colleagues interviewed mothers or caretakers of 1,139 children aged 8 to 15 years and found one in every 10 can be diagnosed with ADHD.

They found a 10-fold increase in one of class of the pesticides was associated with 50 percent increased risk of developing ADHD.

They also found children with above average levels of a metabolite called dimethyl triophosphate were almost twice as likely as those with undetectable levels to develop ADHD.

It is not clear where children got these pesticides. But fruits and vegetables are a possible route.  A health observer cited a report by the Environmental Working Group as saying that certain fruits/vegetables contain high levels of pesticides.

EWG, an evidence-based non-profit organization aiming to educate consumers about Environmental Health, says that up to 37 types of pesticides may be detected in apples.

The organization publishes a list on its website foodnews.org ranking 49 fruit and vegetables based on the severity of pesticide contamination.

Among the 49 fruit and vegetables, onion, avocado, frozen sweet corn, pineapples, mango, sweet sweet peas, asparagus, kiwi fruit, cabbage and eggplant are the ten with lowest levels of pesticides while imported grapes, potatoes, cherries, kale/collard greens, spinach, sweet bell peppers, nectarines, domestic blueberries, apples, strawberries, peaches and celery are the ten containing the highest levels.

David Liu