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NEWTON, Mass. - February 4, 2009 - If your sidewalk or driveway looked like most other people's in the past week, then you must recognize this noise.

It's ice being chipped, scraped, and shoveled away. Local streets have been coated with the stuff lately, and rock salt and ice melt are flying off store shelves.

But where do these products go after they melt? And are they safe to put all over the ground?

WBUR's health and science reporter Sacha Pfeiffer reports.