Depressing because the 4 chemicals (benzene, toluene, ethylbenzen, xylene) are so pervasive in indoor air. And now to find that at levels considered "safe" by the EPA there may be disruption of our hormones (endocrine systems). Of course they are already known to have health effects on the human body other than what is discussed in this study. For example, toluene has a number of central nervous system effects. The EPA says toluene , which is found in highest concentrations in indoor air from the use of common household products (paints, paint thinners, adhesives, synthetic fragrances, and nail polish). Outside - the biggest source of toluene is from automobile emissions. Some ways to lower exposure to these 4 chemicals: read product labels and when using a product that says to use with proper ventilation - open the windows and let the room ventilate! Don't smoke. (For example: the EPA says tobacco smoke contains benzene and accounts for nearly half the national exposure to benzene) The study researchers themselves said the EPA should be paying more attention to these air contaminants. I read this at Scientific American, but it came from EHN:
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.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.
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. Ethylbenzene is one of the top ten chemicals used in children’s products such as toys and playground equipment, according to a 2013 EPA report. Toluene is in the top ten chemicals used in consumer products such as fuels and paints, the report found.
All four get into indoor and outdoor air via fossil fuel burning, vehicle emissions and by volatizing from products. Bolden said studies that measure the air in and around homes and businesses find the chemicals 90 to 95 percent of the time. In several of the monitoring studies Bolden and colleagues examined, levels of the chemicals were higher in indoor air than in outdoor air, suggesting that people might be exposed within their homes. “A lot of time indoor air is poorly circulated,” Bolden said.