Scientists have found that Chicago’s air is infested with chemicals courtesy of airborne compounds that are traveling as far as the Arctic. The chemicals, called cyclic siloxanes, are toxic to aquatic life. Where do they come from? From chemicals in deodorants, lotions and conditioners.
“These chemicals are just everywhere,” said Keri Hornbuckle, an engineering professor at the University of Iowa and senior author of a new study, who also reveals that the concentrations in Chicago are 10 times higher than that in cities in Iowa. “These are big concentrations and, truthfully, are concerning to me.”
In Chicago’s air, the most prevalent compound, known as D5, was at levels three times greater than what polychlorinated biphenyl (PCBs) typically are there. PCBs are persistent chemicals banned in the 1970s. D5 is most commonly used in soaps, lotions, shampoos and conditioners.
The compounds also are probably in high concentrations in the air of many cities, but no one has looked elsewhere yet. The United States produces or imports between 200 million and one billion pounds of cyclic siloxanes annually, according to U.S. Environmental Protection Agency estimates.
Many people rub the compounds all over their bodies every day. They are in about half of all personal care items, comprising up to two-thirds of the product’s mass in some cases, according to a 2008 study by the New York Department of Public Health and a 2009 Health Canada study. They’re used in such products because they are odorless, colorless and feel smooth.
The new study did not track where the airborne chemicals came from, but it suggests that personal care products are a major source since D5 was the dominant compound in both indoor and outdoor air samples.
Indoor air concentrations in University of Iowa labs and offices were 30 and 75 times higher than those in the outdoor air of Cedar Rapids and West Branch, and D5 made up 97 percent of mass of the indoor samples.
“It’s population based,” said Rachel Yucuis, a masters student at the University of Iowa and lead author of the new study, who also notes that the levels of cyclic siloxanes are 2.7 times higher during the day than the night. “And indoors you have both personal products sitting out, and what’s on people, in a concentrated space.”
D4 is a common ingredient used in polishes, detergents, sealants, adhesives, and plastics. And the EPA reports that it is toxic to wildlife even in normal concentrations, let alone high concentrations. D4 has been associated with tumors, reproductive problems, and altered organ sizes in lab animals.
“D4 and D5 are not currently regulated anywhere in the world,” writes MNN. “But the EPA announced in 2012 that it would evaluate whether D4 should be regulated under the Toxic Substances and Control Act. However, the agency is less concerned about outdoor air concentrations than it is about the risks to water-dwelling creatures, an EPA spokesperson said in an email.”
That said, there is some dispute over D4 and D5.
“Despite the size of the dossier submitted by industry for evaluation, it is unfortunate that the dossier lacked meaningful information/data on actual consumer exposure to D4,” said a science panel of the European Commission.
Photo by Yinan Chen