Could a new study suggesting BPA levels in humans are higher than previously thought explain public health trends like a global decline in sperm counts?

A new and more accurate method of measuring BPA levels in humans found that exposure to the hormone-disrupting chemical is far more severe than previously understood, according to a new study from the peer-reviewed scientific journal the Lancet Diabetes & Endocrinology. Researchers found that measurements used by regulatory agencies like the U.S. Food and Drug Administration may be underestimating exposure levels by as much as 44 times.

BPA, or bisphenol-A, is found in a broad range of plastics, canned goods and receipt paper. The chemical has been shown to disrupt essential hormone cycles in animal studies and has been linked to severe problems with growth, metabolism, behavior, fertility and even greater cancer risk in children who experience fetal exposure.

“This study raises serious concerns about whether we’ve been careful enough about the safety of this chemical,” said Patricia Hunt, Washington State University professor and corresponding author on the paper. “What it comes down to is that the conclusions federal agencies have come to about how to regulate BPA may have been based on inaccurate measurements.”

The new research method directly analyzes metabolites, the compounds created as a byproduct of breaking down and eliminating the chemical. Previous research used indirect methods to study BPA metabolite concentrations.

The research team compared the direct and indirect methods and “found much higher levels of BPA using the direct method, as much as 44 times the mean reported by the National Health and Nutrition Examination Survey (NHANES). The disparity between the two methods increased with more BPA exposure: the greater the exposure the more the previous method missed.”

“The regulatory decisions for this chemical, BPA, have been based in part on the idea that our exposure is so very, very low,” Hunt said. “And I just don’t think that’s true. Our data really challenged that assumption.”

“I hope this study will bring attention to the methodology used to measure BPA, and that other experts and labs will take a closer look and assess independently what is happening,” said Roy Gerona, a co-author on the paper who developed the new methodology, urging replication of the method by other research teams.

The new study could contribute to understanding of the alarming global decline in sperm counts, which have fallen by more than 50 percent in the U.S., Europe, Australia, and New Zealand over the last four decades according to a 2017 study conducted by researchers at the Mount Sinai School of Medicine and Hebrew University School of Public Health. “The worldwide trend is largely seen as a mystery, though there is a growing recognition that environmental contaminants play a role,” wrote the Intercept’s Sharon Lerner, a specialist in environmental crime.

BPAS have been shown to interfere with hormones involved in reproductive health, similarly to PFAS, or ‘forever chemicals,’ and phthalates, chemicals that Hunt and Gerona believe may also be vastly underrepresented by inaccurate research methods.

“BPA is still being measured indirectly through NHANES, and it’s not the only endocrine-disrupting chemical being measured this way,” Gerona said. “Our hypothesis now is that if this is true for BPA, it could be true for all the other chemicals that are measured indirectly.”

While many companies have phased out BPA production, the researchers believe BPA replacements may also be dangerous.

The researchers now plan to apply their model to other chemicals, “including environmental phenols such as parabens, benzophenone, triclosan found in some cosmetics and soaps, and phthalates found in many consumer products including toys, food packaging and personal care products.”