U.S. study shows switch to organic diet can quickly clear pesticide from our bodies

Print Email Share Tweet

A new study published Tuesday found that after switching to an organic diet for just a few days, people could cut the levels of a pesticide linked to cancer found in their urine by more than 70 percent.

The researchers collected a total of 158 urine samples from four families –seven adults and nine children – and examined the samples for the presence of the weed killer glyphosate, which is the active ingredient in Roundup and other popular herbicides. The participants spent five days on a completely non-organic diet and five days on a completely organic diet.

“This study demonstrates that shifting to an organic diet is an effective way to reduce body burden of glyphosate… This research adds to a growing body of literature indicating that an organic diet may reduce exposure to a range of pesticides in children and adults,” states the study, which was published in the journal Environmental Research.

Notably, the researchers found that the children in the study had much higher levels of glyphosate in their urine than did the adults. Both adults and children saw large drops in the presence of the pesticide following the diet change. The mean urinary glyphosate levels for all subjects dropped 70.93 percent.

Despite its small size, the study is an important one because it shows people can markedly reduce their exposures to pesticides in food even without regulatory action, said Bruce Lanphear, Professor of Health Sciences at Simon Fraser University.

Lanphear noted that the study showed children appear to be more heavily exposed than adults, though the reason is unclear.  “If the food is contaminated with pesticides, they will have a higher body burden,” Lanphear said.

Roundup and other glyphosate herbicides are commonly sprayed directly over the top of growing fields of corn, soybeans, sugar beets, canola, wheat, oats and many other crops used to make food, leaving traces in finished food products consumed by people and animals.

The Food and Drug Administration has found glyphosate even in oatmeal  and honey, among other products. And consumer groups have documents glyphosate residues in an array of snacks and cereals.

But glyphosate and glyphosate-based herbicides such as Roundup have been linked to cancer and other illness and disease in several studies over the years and growing awareness of the research has led to growing fears about exposure to the pesticide through the diet.

Many groups have documented the presence of glyphosate in human urine in recent years. But there have been few studies comparing glyphosate levels in people eating a conventional diet versus a diet made up only of foods grown organically, without the use of pesticides such as glyphosate.

“The outcomes of this research validate the previous research in which organic diets could minimize the intakes of agrochemicals, such as glyphosate,” said Chensheng Lu, adjunct professor of the University of Washington School of Public Health and honorary professor, Southwest University, Chongqing China.

“In my opinion, the underlying message of this paper is to encourage producing more organic foods for people who want to protect themselves from the exposure of agrochemicals. This paper has proven again this absolute right pathway for prevention and protection,” Lu said.

The study was authored by John Fagan and Larry Bohlen, both of the Health Research Institute in Iowa, along with Sharyle Patton, director of the Commonweal Biomonitoring Resource Center in California and Kendra Klein, a staff scientist at Friends of the Earth, a consumer advocacy group.

The families participating in the study live in Oakland, California, Minneapolis, Minnesota, Baltimore, Maryland and Atlanta, Georgia.

The study is the second of a two-part research project. In the first, levels of 14 different pesticides were measured in the urine of participants.

Glyphosate is of particular concern because it is the most widely used herbicide in the world and is sprayed on so many food crops. The International Agency for Research on Cancer, part of the World Health Organization, said in 2015 that researched showed glyphosate to be a probable human carcinogen.

Tens of thousands of people have sued Monsanto claiming exposure to Roundup caused them to develop non-Hodgkin lymphoma, and many countries and localities around the world have recently limited or banned glyphosate herbicides or are considering doing so.

Bayer, which bought Monsanto in 2018, is attempting to settle more than 100,000 such claims brought in the United States. The plaintiffs in the nationwide litigation also claim Monsanto has long sought to hide the risks of its herbicides.

A California appeals court ruled last month that there was “abundant” evidence that glyphosate, together with the other ingredients in Roundup products, caused cancer.

U.S. regulators relied for years on flawed pesticide data provided by Dow Chemical

Print Email Share Tweet

For years, U.S. regulators relied on falsified data provided by Dow Chemical to allow unsafe levels of the chemical chlorpyrifos into American homes, according to a new analysis from University of Washington researchers.

The analysis reexamines work from the 1970s sponsored by Dow and submitted to the Environmental Protection Agency (EPA) to guide the agency in establishing what scientists refer to as a “no-observed-adverse-effect-level” or NOAEL. Such thresholds are used to determine what types of use and at what level a chemical exposure can be allowed and still be considered “safe.”

According to the new analysis, published online July 3 in the journal Environmental International, the inaccurate findings were the result of a chlorpyrifos dosing study conducted by researcher Frederick Coulston and colleagues from the Albany Medical College in the early 1970s for Dow.

The authors of the new paper reexamining that prior work are Lianne Sheppard, Seth McGrew and Richard Fenske of the Department of Environmental and Occupational Health Sciences, School of Public Health at the University of Washington.

While the study was authored by the Coulston group, the analysis was completed by a Dow statistician and concluded that 0.03 mg/kg-day was the chronic NOAEL level for chlorpyrifos in humans. But the new analysis by the University of Washington researchers found that wildly overstated the margin of safety. Had the data been properly analyzed a lower NOAEL of 0.014 mg/kg-day would have been found, they said.

The Coulston study did not undergo peer review but still was used by the EPA for risk assessments throughout much of the 1980′s and 1990′s, the University of Washington researchers reported.

The researchers concluded: “During that period, EPA allowed chlorpyrifos to be registered for multiple residential uses that were later cancelled to reduce potential health impacts to children and infants. Had appropriate analyses been employed in the evaluation of this study, it is likely that many of those registered uses of chlorpyrifos would not have been authorized by EPA. This work demonstrates that reliance by pesticide regulators on research results that have not been properly peer-reviewed may needlessly endanger the public.”

Widely used

Commonly known as the active ingredient in the brand name Lorsban, chlorpyrifos insecticides were introduced by Dow Chemical in 1965 and have been used widely in agricultural settings. The largest agricultural market for chlorpyrifos is corn but the pesticide is also used by farmers growing soybeans, fruit and nut trees, Brussels sprouts, cranberries, and cauliflower, as well as other row crops. Residues of the chemical are commonly found in food. Non-agricultural uses include golf courses, turf, green houses, and utilities.

Despite the science promoted by Dow, independent scientific research has shown mounting evidence of the dangers of chlorpyrifos, particularly to young children. Scientists have found that prenatal exposures to chlorpyrifos are associated with lower birth weight, reduced IQ, the loss of working memory, attention disorders, and delayed motor development.

The American Academy for Pediatrics, which represents more than 66,000 pediatricians and pediatric surgeons, has warned that continued use of the chemical puts developing fetuses, infants, children and pregnant women at great risk.

Chlorpyrifos is so dangerous that the European Food Safety Authority has stated that there is no safe exposure level.

The EPA reached an agreement with Dow in 2000 to phase out all residential uses of the chemical because of research showing the chemical is dangerous to the developing brains of babies and young children. In 2012, chlorpyrifos was banned from use around schools.

In February 2020, after pressure from consumer, medical, scientific groups and in face of growing calls for bans around the world, Corteva AgriScience, a successor corporation to a merger of Dow and DuPont, said it would phase out production of chlorpyrifos. The chemical, however, remains legal for other companies to make and sell.

Human subjects

The study that is the subject of the new paper by the University of Washington researchers was overseen in 1971 by the Albany Medical College’s Institute of Experimental Pathology and Toxicology. The study included 16 healthy adult male inmates from a pool of volunteers at Clinton Correctional Facility, a maximum-security prison in Dannemora, New York.

The volunteers were randomized into four experimental groups, including one control group, whose members received a daily placebo. The members of the three other groups received daily chlorpyrifos treatments at three different doses.  The study took place over 63 days.

The new analysis found several problems with the study, including the omission of eight valid baseline measurements for one of the three treatment groups.

“Such an omission of valid data without justification is a form of data falsification that violates all standard codes of ethical research practice and is classified as outright research misconduct,” the University of Washington researchers concluded.

The researchers said that chlorpyrifos “passed through the regulatory process without much debate,” even though there was “growing evidence that it might pose a health hazard in residential environments.”

“The Coulston Study misled regulators by omitting valid data,” and “may have adversely impacted public health” for several years, the University of Washington paper concludes.