In a recent study part of a new book, “Environmental Science: Processes & Impacts”, scientist claim that snow acts as a pollutant sponge, absorbing toxic particles in the air before accumulating on the ground.  Hence, yellow snow is not the only snow you should avoid eating!  This quote from the book sums up how the exhaust gets into the snow,“the alteration of exhaust aerosol size distributions at freezing temperatures and in the presence of snow, accompanied by changes of the organic pollutant content in snow, has potential to alter health effects of human exposure to vehicle exhaust.”