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Nithin Coca headshot

Study: Pesticides Are Worse for Human Health When Combined

By Nithin Coca

A study released last week by UCLA found that commonly-used pesticides, which are known to be harmful, can be even worse when mixed, as is commonly done in farms all across California. Until now, these impacts were not being adequately tested by state officials.

The three fumigant pesticides tested in the study -- chloropicrin, telone and metam salts -- are often mixed, either in how they are sold or how they are applied on farms. Amazingly, these combinations were never properly tested by regulators. Thanks to the University of California, Los Angeles, we now know how these combinations impact human health – and it's not good.

“[Our] research shows that pesticide mixtures can interact to cause larger-than-anticipated impacts on public health,” said Timothy Malloy, faculty director of the Sustainable Technology and Policy Program at UCLA and one of the report’s authors, in a statement. “Farm workers and local residents are especially at risk, given that they may be exposed to two or more pesticides simultaneously or in sequence.”

Here's the scary part – these pesticides are found even near schools. That's right – children, who are often more prone to adverse health impacts from chemicals, could be exposed to dangerous pesticide combinations all across California. That is why, in response to the report, a coalition of parents, health professionals and food advocates is calling for the state to implement new restrictions on pesticide use.

“We face a growing epidemic of cancer and other threats to children’s health and learning potential,” said Emily Marquez, a staff scientist at the Pesticide Action Network, in a press statement. “Just like prescription drugs, when used in combination pesticides can grow in potency. The only difference is that state officials aren’t paying attention to these interactions.”

The report calls on the state to make three big changes: test pesticides that are sold as part of a mixture for interactive toxic effects before approving their use; require evaluation of products that are not used as part of a mixture but are used in combination or sequentially with other pesticides; and consider pesticides’ interactive effects when performing risk assessments and establishing management requirements.

This is only the latest in a long series of research showing the harmful impacts of traditional agriculture. I believe we have to change our approach to pesticides. Currently, we allow them to be used indiscriminately until we learn about a negative impact, and even then, big agriculture's lobbyists do all that they can to resist change.

How about, from now on, we ban all pesticides unless their manufacturers can prove, without a doubt, that they cause no harm to both the environment and human health, either in isolation or, as this study finds, in combination with other pesticides? Let's shift the burden of proof onto big agricultural companies, and let's promote organic food with the same subsidies that now benefit pesticide-intensive agriculture. It's time to change our food system to protect us, our children and our environment. Enough is enough.

Image credit: TSPDave via Pixabay

Nithin Coca headshot

Nithin Coca is a freelance journalist who focuses on environmental, social, and economic issues around the world, with specific expertise in Southeast Asia.

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