Mercury’s bad! (Other than Freddie.) That’s why the U.N. is outlawing it in your thermometers, light bulbs, and batteries, because DANGER and health risks and environmental hazards. But if you want to keep applying mercury directly to your eyes, THAT’s cool. If that does not compute, Scientific American can explain:

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Last week, about 140 countries signed the United Nations’ Minamata Convention, which includes a ban on mercury in cosmetics and soaps. But mascara and other eye makeup is exempt because “no effective safe substitute alternatives are available” and “the intention is not to cover cosmetics, soaps or creams with trace contaminants,” the treaty says.

Mercury is sometimes used in small amounts in mascara as a preservative and a germ-killer. In the United States, the Food and Drug Administration allows it in eye cosmetics at a concentration of up to 65 parts per million.

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Basically, mercury kills fungi and bacteria that would otherwise hang out in your mascara tube like it was some bathroom party pad. Unfortunately, as science reveals, mercury also kills your brain and kidneys!

Mercury is a potent neurotoxicant. High levels can cause serious neurological effects and kidney damage, and, if a pregnant woman is exposed, lower concentrations can disrupt the brain of a developing fetus …

Stacy Malkan, co-founder of the advocacy group Campaign for Safe Cosmetics, said there is no reason “a known neurotoxin should be allowed in any of these products” because most companies already have found alternatives.

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Most … but not all. Revlon subsidiary Bari Cosmetics makes six mascaras with thimerosal, a preservative containing mercury. Thankfully, other companies have found thimerosal substitutes: parabens and formaldehyde. Hooray! Wait, NOT HOORAY. Although those puppies aren’t as bad for you as mercury, they’re STILL linked to cancer and screw with your hormones.

I’m not sure why the U.N. didn’t include mascara in the mercury ban, but we should probably switch to smearing lumps of charcoal on our eyes or whatever Disney princesses do (right after they use strawberries for lipstick). That or go au naturel and stick it to cosmetics companies.