Another Class of Pesticides Is Destroying Brains

Analysis by Dr. Joseph Mercola Fact Checked

organophosphate pesticides

Story at-a-glance

  • A class of pesticides called organophosphates (OPs) has been implicated for the brain-destroying health risks — such as attention and memory deficits, autism and lower IQs — they present to children
  • A meta-analysis of OP data from 71 countries suggests these chemicals should be banned due to the significant health threat they pose to children and pregnant women
  • Pesticide regulations vary widely worldwide and are not always well enforced; chemicals banned in one country can be exported elsewhere
  • In the U.S., the safety of an OP called chlorpyrifos, produced by Dow Chemical Company, is being hotly debated even though it is known to be highly toxic
  • The Trump administration is in the process of rolling back the age limits on restricted-use pesticides, including chlorpyrifos, to allow workers as young as 16 to spray the toxic chemicals


This is an older article that may not reflect Dr. Mercola’s current view on this topic. Use our search engine to find Dr. Mercola’s latest position on any health topic.

While there are many sources of exposure to toxic chemicals, the use of organophosphates (OPs) is making news once again for the damage it causes to children's brains.

A group of environmental and public health researchers from the U.S. and Canada suggest prenatal exposure to OPs is putting children at risk for behavioral and cognitive deficits, as well as neurodevelopmental disorders. For this reason, they are calling for a global phaseout of these toxic chemicals, among other measures.

OP Pesticides Flagged as Significant Risk to Children and Pregnant Women

Authors of a study published in the journal PLOS Medicine1 suggest OPs pose significant health risks to children, including attention and memory deficits, autism and reduced IQ.

Based on a meta-analysis of data and literature on OPs contained in a United Nations (U.N.) database2 housing information reported by 71 countries, the team asserts these chemicals are such a significant threat to the health of children and pregnant women they should be banned.

With respect to the findings, lead author, professor Irva Hertz-Picciotto, Ph.D., environmental epidemiologist and director of the Environmental Health Sciences Core Center at the University of California, Davis, called the U.S. Environmental Protection Agency (EPA) to action, saying:3

"We have compelling evidence from dozens of human studies that exposures of pregnant women to very low levels of organophosphate pesticides put children and fetuses at risk for developmental problems that may last a lifetime. By law, the EPA cannot ignore such clear findings: It's time for a ban not just on chlorpyrifos, but all organophosphate pesticides."

Picciotto and her team noted:4

  • OP compounds were originally developed in the 1930s and 1940s for use as human nerve gas agents; some were later adapted at lower doses for use as insecticides5
  • People are routinely exposed to OP pesticides due to their wide use in agriculture, on golf courses and in homes, parks, rights of way, schools and countless public spaces
  • More than 40 OP pesticides, including those most commonly used, are now considered by the EPA, the World Health Organization (WHO) and the U.N.'s Food and Agriculture Organization (FAO) to be moderately or highly hazardous to human health6
  • In the U.S., a number of OP pesticides, including azinphos-methyl, chlorpyrifos, dichlorvos and malathion, were licensed for insecticidal use prior to the establishment of regulations requiring them to be evaluated for ecologic and human health impacts7
  • To date, U.S. regulators have already banned 26 out of 40 OP pesticides considered to be human health hazards, whereas the European Union has banned 33 of 398

Pesticide Bans Vary by Country and Are Not Well Enforced

The researchers were quick to note pesticide regulations vary widely around the world and are not always well enforced. Even when a certain toxic pesticide is banned in one country, it can still be exported elsewhere.

Very often these products end up in developing countries. Regions like Central America, where agricultural chemicals are less regulated, have been impacted.9 In addition, earlier this year, I discussed how agrochemicals have increased birth defects and deformities in Argentinian children.

Authors of a 2001 study published in the journal Toxicology10 observed developing countries with warmer climates, where the growing season allows for the cultivation of two or three crops a year — much of which is exported to regions with colder climates and shorter growing seasons — are increasingly impacted by toxic agricultural chemicals. The researchers stated:11

"Many older, [nonpatentable], more toxic, environmentally persistent and inexpensive chemicals are used extensively in developing nations, creating serious acute health problems and local and global environmental contamination.

Few developing nations have a clearly expressed 'philosophy' concerning pesticides. There is a lack of rigorous legislation and regulations to control pesticides, as well as training programs for personnel to inspect and monitor use."

According to the current study, at least a dozen OP pesticides classified by the WHO/FAO as highly hazardous are still being used in Mexico.12 Based on the large amount of produce imported to the U.S. from that country, such news is of particular concern to Americans. This is just one more reason to avoid conventional produce and buy organic fruits and vegetables as often as possible.

The Dangers of Chlorpyrifos, One of the Most Commonly Used Pesticides

Although you may not have heard of chlorpyrifos, scientists at Harvard University assert it's very likely to be found inside your body based on the fact it is the most widely-used pesticide on American farms.13 Having been invented as an alternative to the caustic dichlorodiphenyltrichloroethane (DDT) — which was itself a replacement for toxic lead arsenate — chlorpyrifos is said to be the latest in a group of "regrettable substitutions."14 Beyond this, chlorpyrifos:15

  • Was banned from household use by the EPA in 2000
  • Continues to be sprayed on agricultural crops and is routinely applied to golf courses and public spaces
  • Kills insect pests by attacking their nervous system; its impact on humans is somewhat similar
  • When sprayed on food crops, the farmworkers applying chlorpyrifos may experience confusion, dizziness and nausea

Sharing more facts about chlorpyrifos, the Environmental Working Group (EWG) states:16

"Use of chlorpyrifos is heaviest in [U.S.] areas dominated by agriculture, including California, the Northwest and the Midwest. It is applied on grapes; on tree fruits such as apples, nectarines, peaches, citrus and almonds; and on corn, wheat and soybeans.

Researchers with the U.S. Department of Agriculture, which tests produce for pesticide residues each year, estimate that almost half of conventionally grown apples are sprayed with the pesticide. Americans are also exposed to chlorpyrifos residues on imported produce."

Corporate Profits and Industry Interests Prioritized Over Human Health

In the U.S., the battle over how to handle toxic pesticides continues to be waged, pitting corporate profits and the interest of industry trade groups against human health. August 2018, a U.S. federal appeals court mandated the EPA ban the use of chlorpyrifos with respect to its remaining applications.17

The judgment, which is currently under appeal, countered the EPA's 2017 reversal of the Obama administration's efforts to eliminate the poison two years earlier. The EWG suggests political ties between U.S. President Donald Trump and Dow Chemical Company, manufacturer of chlorpyrifos, initially stalled the action to more comprehensively ban the pesticide.18

According to EWG, Dow contributed $1 million to President Trump's inaugural ball in 2017. Alleged conversations in early 2017 between former EPA administrator Scott Pruitt, who was forced to resign in July 2018 due to ethical scandals, and Dow's CEO are believed to have resulted in Pruitt reversing the agency's proposal to ban chlorpyrifos from use on food crops.19

As such, Pruitt ignored the recommendation of EPA scientists, who, in November 2016, had revised both their human health risk and drinking water exposure assessments for chlorpyrifos, highlighting the potential health risks of exposure to chlorpyrifos residues in food and drinking water.

About the planned revision, the EPA states, "Currently, chlorpyrifos remains registered as it undergoes registration review. As part of the ongoing registration review, we will continue to review the science addressing neurodevelopmental effects and complete our assessment by October 1, 2022."20

With respect to corporate interests, the Union of Concerned Scientists states, "The power that companies like Dow Chemical wield in government can give them special access to administration officials, which in turn can allow them to unduly influence federal policies in ways that serve corporate interests rather than the public interest."21

Proposed Rollback on Pesticide Application Age Limits Also Puts Children at Risk

The Global Justice Ecology Project22 says the Trump administration also intends to roll back the age limits on restricted-use pesticides, including chlorpyrifos, to allow workers as young as 16 years old to spray the toxic chemicals.23 This recommendation was first announced by Pruitt last year and is set to take effect in September 2019.

Previously, the Obama administration had established the minimum age rules to protect minors working on farms, many of whom are teenage (or younger) migrant workers speaking little, if any, English. Given the language barrier, it can be challenging for them to understand directions on how to apply pesticides safely.

EWG President Ken Cook did not mince words when commenting on the Trump administration's plans to allow kids as young as 16 to handle health-damaging pesticides. In addition to calling the administration's actions a "war on children's health,"24 Cook said:25

"There are other farm jobs they could do that don't involve strapping containers of dangerous chemicals on their backs that they will inhale and ingest. But this administration will let unscrupulous farm bosses risk these kids' health. Maybe the President should pick up a spray nozzle for a day and see what it's like walking through a plume of pesticide fumes."

Beyond this, the EWG suggests a decision by acting EPA administrator Andrew Wheeler in September 2018 to place the EPA's top children's health official, Dr. Ruth Etzel, on administrative leave may be the first step toward eliminating a team assigned to "reduce negative environmental impacts on children" through involvement in EPA activities such as policy enforcement, research and rulemaking.26

Etzel, a pediatrician and specialist in preventive medicine and public health, who has been a leader in children's environmental health for 30 years, was assigned as director of the EPA's Office of Children's Health Protection in 2015.

The removal of Etzel may be "the opening gambit in a plan by this administration to dismantle [the] EPA's Office of Children's Health Protection," says Dr. Philip Landrigan, one of the world's leading authorities on children's health and founding director of Boston College's global public health initiative.27

Pesticide Impacts on Children's Brains and How to Prevent Harm

While you may think adults and children are equally susceptible to the toxic side effects of pesticides like chlorpyrifos, EarthJustice, creator of the video shown above, notes, "Children often experience greater exposure to chlorpyrifos and other pesticides because they frequently put their hands in their mouths and, relative to adults, they eat more fruits and vegetables, and drink more water and juice for their weight."28

Robin Whyatt, deputy director of the Columbia Center for Children's Environmental Health at Columbia University in New York and coauthor of the October 2018 research, told the Guardian the impact of OPs on children's brains, while relatively low in terms of actual IQ points on a child by child basis, could result in long-term, negative societal shifts. She said:29

"The problem is that when you have an exposure as ubiquitous as [OPs], 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."

According to Whyatt, a good deal of the neurological damage linked to OP use impacts working memory, which, she notes, relates to your brain's ability to retain and recall short-term thoughts. As such, a child's brain that has been damaged by OPs may be able to retain only a portion of an instruction such as "open your science textbooks to page 37 and began [sic] exercise number four," she said.30

Another study coauthor, Bruce Lanphear, professor of health sciences at Simon Fraser University in British Columbia, Canada, stated:31

"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."

Recommendations to Protect Children From Pesticides

The group of study authors offered a number of specific recommendations to help protect children, including the call to phase out chlorpyrifos and other OP pesticides worldwide. With respect to their other suggestions, most of which will need to be addressed by government leaders and other policy influencers, the researchers invited global entities to:32

Encourage the use of integrated pest management (IPM) through incentives as well as training in agroecology

Ensure worker safety through proper training and the use of protective equipment

Implement mandatory surveillance of pesticide-related illness

Increase education on the hazards of OPs in medical and nursing schools, as well as continuing education courses targeting health care professionals

Monitor watersheds and other sources of human exposures to OPs

Promote the development of nontoxic approaches to pest control through IPM

While the battle around OPs and other toxic pesticides is waged, you can safeguard your health and the health of your children at the most basic level by purchasing organic, pesticide-free foods as often as possible. For more tips, check out my article "Which Fruits and Vegetables Have the Most Pesticides?" or refer to the EWG's "2018 Shopper's Guide to Pesticides in Produce."33

An even safer choice is to grow your own food. Because pesticide residues can transfer from peels to your hands, be sure to wash foods well before eating, even if you plan on peeling it afterward.

As a final thought, remember change comes from people, not governments or other high-level entities. Whether you realize it or not, you vote with your wallet. Every purchase you make influences the change you want to see. About this, André Leu, organic farmer, director of Regeneration International and author of "Poisoning Our Children: The Parent's Guide to the Myths of Safe Pesticides," in an interview about the myths of safe pesticides, said:

"You have to make this change yourself. It's simple to make. If enough of us are making this change, we'll actually change agriculture because the retailers and farmers will be forced to change production to meet the market.

Buying organic food, buying local food, going to Community-Supported Agriculture (CSAs), is actually a very powerful political and change act. Your dollars will do more to change the system than probably anything else."


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