Home > Uncategorized > Science and Regulations Matter… as Lead, Chlorofluorocarbons, and Chlorpyrifos Illustrates

Science and Regulations Matter… as Lead, Chlorofluorocarbons, and Chlorpyrifos Illustrates

May 17, 2017

Decades ago, scientists determined that lead in the atmosphere and in the paints used in houses caused brain damage. Government officials listened to the scientists and, over the objections of corporations, developed and enforced regulations on the use of lead. The well-being of several generations improved as a result.

In the 1980s, scientists determined that chlorofluorocarbons were causing the depletion of the ozone layer around the earth and thereby contributing to climate change and skin cancer. Government officials listened to the scientists and, over the objections of corporations, developed and enforced regulations on the use of chlorofluorocarbons. The hole in the atmosphere stopped growing and is now on the way to closing entirely  as a result….  and the well-being of several generations improved as a result.

As reported in an article by Roni Caryn Rabin in Monday’s NYTimes, a recent study by Columbia University researchers determined that chlorpyrifos, a chemical used to control bugs in homes and fields for decades, caused brain damage in baby rats. Two years into the researchers’ study,  the pesticide was removed from store shelves and banned from home use. Why?

Scientists soon discovered that those with comparatively higher levels (of chlorpyrifos) weighed less at birth and at ages 2 and 3, and were more likely to experience persistent developmental delays, including hyperactivity and cognitive, motor and attention problems. By age 7, they had lower IQ scores.

The Columbia study did not prove definitively that the pesticide had caused the children’s developmental problems, but it did find a dose-response effect: The higher a child’s exposure to the chemical, the stronger the negative effects. 

That study was one of many. Decades of research into the effects of chlorpyrifos strongly suggests that exposure at even low levels may threaten children. A few years ago, scientists at the Environmental Protection Agency concluded that it should be banned altogether.

So once again we have a situation where a scientific finding informed a government agency who took relatively swift action to address a problem affecting the well-being of citizens. But now a new President, who sees regulations as an impediment to profits, appoints an agency head who intends to do everything possible to roll back those pesky regulations. As Ms. Rabin reports:

In March, the new chief of the E.P.A., Scott Pruitt, denied a 10-year-old petition brought by environmental groups seeking a complete ban on chlorpyrifos. In a statement accompanying his decision, Mr. Pruitt said there “continue to be considerable areas of uncertainty” about the neurodevelopmental effects of early life exposure to the pesticide.

Even though a court last year denied the agency’s request for more time to review the scientific evidence, Mr. Pruitt said the agency would postpone a final determination on the pesticide until 2022. The agency was “returning to using sound science in decision-making — rather than predetermined results,” he added.

Agency officials have declined repeated requests for information detailing the scientific rationale for Mr. Pruitt’s decision.

So after a study by reputable researchers concluded that exposure to chlorpyrifos resulted in “persistent developmental delays, including hyperactivity and cognitive, motor and attention problems” and was linked to lower IQ scores by the time those children were 7 years old, because of “considerable uncertainty about the neurodevelopment effects” of this pesticide, the ban on it will be lifted.

Ms. Rabin provides a comprehensive overview of the research that caused the EPA to reach its conclusion to ban the pesticide, noting that while research on animals exposed to chlorpyrifos is unequivocal and wholly negative:

Scientists have been studying the impact of chlorpyrifos on brain development in young rats under controlled laboratory conditions for decades. These studies have shown that the chemical has devastating effects on the brain.

“Even at exquisitely low doses, this compound would stop cells from dividing and push them instead into programmed cell death,” said Theodore Slotkin, a scientist at Duke University Medical Center, who has published dozens of studies on rats exposed to chlorpyrifos shortly after birth.

In the animal studies, Dr. Slotkin was able to demonstrate a clear cause-and effect relationship. It didn’t matter when the young rats were exposed; their developing brains were vulnerable to its effects throughout gestation and early childhood, and exposure led to structural abnormalities, behavioral problems, impaired cognitive performance and depressive-like symptoms.

But the research on human subjects is less unequivocal, and the manufacturers of chlorpyrifos have seized on that ambiguity…. and in President Trump’s EPA, it appears that corporate interests will outweigh the well-being of those exposed to chlorpyrifos:

Manufacturers say there is no proof low-level exposures to chlorpyrifos causes similar effects in humans. Carol Burns, a consultant to Dow Chemical, said the Columbia study pointed to an association between exposure just before birth and poor outcomes, but did not prove a cause-and-effect relationship…

Dr. Burns argues that other factors may be responsible for cognitive impairment, and that it is impossible to control for the myriad factors in children’s lives that affect health outcomes. “It’s not a criticism of a study — that’s the reality of observational studies in human beings,” she said. “Poverty, inadequate housing, poor social support, maternal depression, not reading to your children — all these kinds of things also ultimately impact the development of the child, and are interrelated.”

Brenda Eskenazi, director of the Center for Environmental Research and Children’s Health at the University of California, Berkeley, believes the marketplace will sort this all out… but not in a way that can assure the well-being of citizens who are, in effect, serving as lab rats:

In California, the nation’s breadbasket, use of chlorpyrifos has been declining, Dr. Eskenazi said. Farmers have responded to rising demand for organic produce and to concerns about organophosphate pesticides.

She is already concerned about what chemicals will replace it. While organophosphates and chlorpyrifos in particular have been scrutinized, newer pesticides have not been studied so closely, she said.

“We know more about chlorpyrifos than any other organophosphate; that doesn’t mean it’s the most toxic;” she said, adding, “There may be others that are worse offenders.”

The demand for organic produce is undoubtedly coming from well-heeled and well educated consumers. The consumers who cannot afford the organic produce will be the ones subjected to chlorpyrifos and the newer pesticides. In the meantime, Dow chemical shareholders will be pleased.

%d bloggers like this: