Energy & Environment

For thousands of common chemicals, there is ‘no safe level,’ says report

Plastics, pesticides and forever chemicals are exposing billions of people around the world to pernicious and dangerous health effects, a new report has found.

In the report published Monday, scientists from the Endocrine Society and the International Pollutants Elimination Network criticized the way regulators determine the toxicity level of chemicals — and suggested that for a staggering array of common compounds, no dose may be safe.

This is a problem scientists connect to the rising production from the fossil fuel and petrochemical industries.

“There is good reason to suspect that increasing chemical and plastic production and use are related to the growing incidence of endocrine- associated disorders over the past 20 years,” the report found.

The authors noted that plastic sales had increased thirty-fold since 1970 — and that annual production had gone up by a factor of nine. That’s an increase that had corresponded with a dramatic rise in diseases such as obesity, as well as similarly stark falls in male fertility.


“It’s a public health problem if people who want to have families can’t have them,” report lead author Andrea Gore, an endocrinologist of the University of Texas, told The HIll.

“It’s also a public health problem — and maybe a bigger public health problem — that endocrine disruptors are associated with greater likelihood to have obesity and Type 2 diabetes. Those are huge public health problems that are very costly, both to the individual and to society.”

The report points to mounting evidence that a wide array of compounds — pesticides such as glyphosate, plastics additives, forever chemicals (PFAS), phthalates, bisphenols — play an insidious role in chronic disease.

These compounds are known as endocrine-disrupting chemicals (EDCs) because their size and shape resemble the messenger molecules, or hormones, that human and animal bodies use to govern a wide range of physical systems.

With about a quarter of diseases likely caused by environmental factors — and more than three-quarters of the most deadly — endocrinologists and public health experts have increasingly focused on the EDCs that are found in everything from food to children’s toys to furniture.

Those chemicals “may contribute to disorders with hormonal underpinnings such as diabetes, neurological disorders, reproductive disorders, inflammation, and compromised immune functioning,” the report found.

While they’re likely not safe for people of any age, they’re particularly dangerous to the developing bodies of fetuses and young children, the report found.

The scientists also pinpointed the distinct risks of rising production of plastics, which creates a host of problems from production to waste-disposal or recycling, with pronounced dangers for children.

The report highlights several assumptions that the regulators of industrialized countries have made as they assess what compounds are safe for spraying on food or using to build consumer goods — assumptions that turn out to be dangerous.

First and most glaring is the idea that the compounds that we spray on food, dump into waterways or put into food containers won’t enter our bodies in the same levels as those same compounds if they were added to food.

“These chemicals, for the most part, are not intended to be in food,” Gore said. “Nobody planned to cook [bisphenol A] or any of these industrial chemicals into food — but they’ve gotten into food.”

“And the way chemicals are regulated in food is different from how you would regulate a chemical, let’s say, in a water bottle.”

According to the report, another likely invalid assumption regulators make is the one offered by the American Chemistry Council that sufficiently low doses of toxic chemicals are safe.

This is a reasonable assumption for many otherwise toxic compounds — the deadly poison cyanide is innocuous when found in trace amounts in apples.

But in the case of EDCs, “that approach doesn’t work, because the body’s endocrine system is exquisitely sensitive to hormones,” Gore said.

“And it is also exquisitely sensitive to chemicals that can mimic or block hormones. The regulatory toxicology system doesn’t even look at their chemicals at those low doses, because they’re looking for these overly toxic effects — and are not looking for impacts on sperm count. They’re not looking at behavioral changes. They don’t they don’t dive in at that level.”

This gap has led endocrinologists to focus on chemicals at the levels at which the public is actually exposed to them.

“That’s a typically pretty low dose, fortunately,” Gore said. “But unfortunately, we also know that chemicals can activate those low doses.”

For example, the herbicide glyphosate — which was found in the urine of more than 80 percent of Americans in 2014 — alters the expression of sex hormones even at low levels. Studies have found that women in agricultural regions of Indiana were more likely to give premature birth; that pregnant women in Ontario exposed to glyphosate were more likely to miscarry; and that the children of pesticide applicators were more likely to have “neurobehavioral deficits.”

Then there is bisphenol A (BPA), a “plastizer” that makes plastic products like baby bottles or the inside of cans flexible. While there are replacements for BPA that do the same thing, the report found that “it is impossible for the consumer to know which do and which do not.” (One study of “BPA-free” products found that about two-thirds contained BPA.)

BPA is dangerous because of its close resemblance to the “female” hormone estrogen — which among other things helps trigger the start of puberty in girls. (The age at which girls experience puberty is dropping, and some studies suggest that girls with early-onset menses have higher levels of BPA in their blood, though results are contradictory.)

Women struggling to get pregnant during in vitro fertilization also tended to have higher levels of BPA in their blood, according to a 2011 study.

And then there are metabolic consequences, Gore said. BPA interferes with cells that make insulin, which breaks down the sugars absorbed after we eat.

These systems are complicated, Gore emphasized. But while far more science must be done, she said regulators can’t wait for conclusive answers.

“These chemicals pose particularly serious risks to pregnant women and children,” she said. “Now is the time for the U.N. Environment Assembly and other global policymakers to take action to address this threat to public health.”