Scientists Warn of Hormone Impacts From Benzene, Xylene, Other Common Solvents

Four chemicals present both inside and outside homes might disrupt our endocrine systems at levels considered safe by the U.S. Environmental Protection Agency, according to an analysis released today.

The chemicals – benzene, toluene, ethylbenzene and xylene – are ubiquitous: in the air outside and in many products inside homes and businesses. They have been linked to reproductive, respiratory and heart problems, as well as smaller babies. Now researchers from The Endocrine Disruption Exchange (TEDX) and the University of Colorado, Boulder, say that such health impacts may be due to the chemicals’ ability to interfere with people’s hormones at low exposure levels.

“There’s evidence of connection between the low level, everyday exposures and things like asthma, reduced fetal growth,” said Ashley Bolden, a research associate at TEDX and lead author of the study. “And for a lot of the health effects found, we think it’s disrupted endocrine-signaling pathways involved in these outcomes.”

Bolden and colleagues – including scientist, activist, author and TEDX founder Theo Colborn who passed away last December – pored over more than 40 studies on the health impacts of low exposure to the chemicals.

“Hormones are how the body communicates with itself. Interrupt that, you can expect all sorts of negative health outcomes.”
—Susan Nagel, University of Missouri-Columbia(Colborn also co-authored “Our Stolen Future” along with Dianne Dumanoski and Pete Myers, founder of Environmental Health News and chief scientist at Environmental Health Sciences.)

They looked at exposures lower than the U.S. Environmental Protection Agency’s reference concentrations for the chemicals, which is the agency’s estimated inhalation exposure level that is not likely to cause health impacts during a person’s lifetime.

Many of the health problems – asthma, low birth weights, cardiovascular, disease, preterm births, abnormal sperm – can be rooted in early disruptions to the developing endocrine system, Bolden said.

The analysis doesn’t prove that exposure to low levels of the chemicals disrupt hormones. However, any potential problems with developing hormone systems are cause for concern.

“Hormones are how the body communicates with itself to get work done. Interrupt that, you can expect all sorts of negative health outcomes,” said Susan Nagel an associate professor at the University of Missouri-Columbia Obstetrics, Gynecology and Women’s Health School of Medicine who was not involved in the study.

Cathy Milbourn, a spokesperson for the EPA, said in an emailed response that the agency will “review the study and incorporate the findings into our work as appropriate.”

The “EPA is screening thousands of chemicals for potential risk of endocrine disruption,” she said. “As potential risk of endocrine disruption is identified, these chemicals are assessed further.”

The four chemicals are retrieved from the wellheads during crude oil and natural gas extraction and, after refining, are used as gasoline additives and in a wide variety of consumer products such as adhesives, detergents, degreasers, dyes, pesticides, polishes and solvents.