Scientists call for ban on pesticides that harm children's brains

plane spraying a field
CC BY 2.0 Santiago Nicolau

New study says there's no safe level of exposure to organophosphates, a main ingredient in pesticides.

A panel of toxicology experts would like to see an entire class of pesticides banned from use. The chemicals in question are organophosphates (OP), developed as human nerve gas agents in the 1930s-40s and adapted as agricultural pesticides in the 1960s. Their use hasn't remained in the fields, however, but has spread to hospitals, healthcare institutions, schools, parks, golf courses, shopping malls, and playing fields for pest control purposes (i.e. spraying for mosquitoes). They're used in flea and tick treatments for pets. This means that ever more humans are coming into contact with OP chemicals.

A study, just published in October in the journal PLOS Medicine, reveals that there is no safe level of exposure for pregnant women and children when it comes to organophosphates. Even low levels of exposure put fetuses at risk for long-term developmental problems that might not manifest until later in childhood. One of the paper's eight co-authors, Bruce Lanphear of Simon Fraser University in Vancouver, said,

“We found no evidence of a safe level of organophosphate pesticide exposure for children. Well before birth, organophosphate pesticides are disrupting the brain in its earliest stages, putting them on track for difficulties in learning, memory and attention, effects which may not appear until they reach school-age. Government officials around the world need to listen to science, not chemical lobbyists.”

Disorders range from "impaired mental and motor skills and memory loss to autism and attention-deficit hyperactivity disorder." OPs harm memory and the capacity to retain short-term thoughts. From the Guardian: "[An affected] child might only remember one or two parts of an instruction such as 'open your science textbooks to page 37 and began exercise number four.'"

OPs can decrease IQ by four or five points, which, as co-author Robin Whyatt of Columbia University said, "would probably not have a huge impact," but becomes problematic in the big picture:

“When you have an exposure as ubiquitous as this, you get distributional shifts in IQ, with fewer people in the brilliant range and more in the lower ranges of IQ. That can have a very substantial economic impact on societies in terms of the ruined potential of children’s abilities.”

The study authors would like to see OPs banned, both for agricultural and non-agricultural purposes. The Environmental Protection Agency was on track to banning their use on food crops, but two years ago the Trump administration abandoned these plans, going against scientists' recommendations. The Huffington Post reports that in August a federal court ordered the EPA to enact the ban, but the agency is appealing it.

Meanwhile, in Europe, 33 out of 39 organophosphate pesticides are banned, which is significantly more than the 26 out of 40 that are currently banned in the United States. Despite these efforts to control their use, OPs are fourth among the 24 most commonly imported chemicals to Central America.

High levels of exposure lead to acute poisoning, as is the case with many pesticides. The UN estimates 200,000 deaths annually from pesticide poisonings, 99 percent of which occur in the developing world, with an additional 110,000 pesticide-induced suicides each year.

The study offers several recommendations. While working toward a global phase-out, the authors would like to see interim measures put in place, including reducing human exposure by limiting pesticide application near residences and schools, and not using aerial spray methods; instituting regular monitoring of watersheds to limit pollution; the establishment of a nationally-coordinated pesticide reporting system; and better education for healthcare professionals about the signs of pesticide poisoning.

As citizens we can fight by buying organic produce (voting with our dollars), washing all fruits and vegetables thoroughly, even if we're peeling them, and speaking to local representatives.

Scientists call for ban on pesticides that harm children's brains
New study says there's no safe level of exposure to organophosphates, a main ingredient in pesticides.

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