Sure, yellow's a cheery color, but we might have to pass on the yellow undies we got for Christmas. According to a new Rutgers University study, yellow dyes contain a potentially toxic chemical named PCB 11. Back in the 70s, the U.S. and Canada banned the manufacture of PCBs, also known as polychlorinated biphenyls. But PCB 11 is a different (and therefore legal) form of the chemical, and can be found in yellow dyes, inks, and paints. Because it's a by-product of PCB, the 1979 ban doesn't apply.
The Rutgers study, it should be noted, is undergoing peer review and is expected to be published later this year. In the study, researchers examined 28 samples of paper products, from postcards to napkins, that contained ink and were manufactured outside of America.
Each of those 28 samples had some degree of PCB 11. The study also tested 18 samples of ink-treated paper products manufactured in America — and of those, 15 contained some level of PCB 11.
The chemical can enter the human body through airways and skin. In a 2010 University of Iowa study, 60 percent of blood samples tested in women showed traces of PCB 11, though its unclear if those traces are anywhere near enough to cause ill effects. Waterways, including the New York-New Jersey Harbor and Delaware River, also have been shown to contain PCB 11.
The exact effects of PCB 11 aren't clear — but the rate at which they're appearing in yellow dye should be a cause for concern, the study's senior author, Lisa Rodenburg, told Environmental Health News. Rodenburg, an associate professor of chemistry at Rutgers, expanded: "Even at the parts per billion levels, if you find it in almost everything you test, that means people are in almost constant contact."
So... do we need to throw out our lovely yellow dresses, shirts, ties, bras, boxers? Repaint school buses green?
Not just yet. The Environmental Protection Agency is still assessing the risks of PCB 11. While PCB was banned as a result of many factors — for example, it was a probable human carcinogen, and had adverse effects on the immune system — PCB 11 as a by-product may have a different impact on the human body, if any.
Until then, maybe orange really is the new black?