http://www.iflscience.com/environment/snow-sponge-toxic-car-exhaust-particles

Why You Shouldn't Eat ANY Snow, Not Just Yellow Snow

You know the saying: Don’t eat yellow snow. Unfortunately, a new study published in the journal Environmental Science: Processes & Impacts, suggests that you shouldn’t actually eat any snow at all, if you can avoid it. Snow has been found to act as a rather effective sink for tiny particles that are found primarily in car exhaust fumes, so any consumption of it is effectively like eating a pollution-flavored Popsicle.

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