Q What's the best way to keep a sidewalk ice-free? Is there a deicer that's safer for concrete and doggie paws?

A A sidewalk deicer such as Safe Paws Ice Melter (www.safepaw.com), is less irritating to pet paws than traditional deicers, and better for the environment, according to National Geographic's Green Guide.

Generallly, to keep walks ice-free, remove snow promptly. If ice builds up and won't yield to snow shovels, ice chippers are the tools to use. They're available at hardware and home stores for $15 to $30.

If mechanical removal doesn't work, then spread deicer. But read the labels and pick your product carefully.

• Sodium chloride kills plants and grass, poisons soil and can lead to concrete problems.

• Calcium chloride works at very low temperatures, but also can result in concrete problems.

• Potassium chloride doesn't work in extreme cold, but is kinder to plants and concrete.

• Corn-based products, such as Safe Walk (www.safe-walk.com), contain the chlorides found in traditional deicers and other trace elements, it'll work in subzero temperatures, yet it's supposedly safer for lawns and gentler on pet feet.

In any case, it's a good idea to use as little deicer as possible and to protect trees and plants from deicers.

More on melamine In response to a recent column on the safety of milk in this country, Adam Ismail, executive director of the Global Organization for EPA and DHA Omega-3s, wrote:

"One other thing that is relevant is that in the United States, we primarily consume fresh liquid milk, but in China they primarily consume powdered milk, which is one of the primary sources of nourishment and is usually fortified with vitamins and other nutrients. Fresh milk in the U.S. meets a standard of identity and is sold on a volume basis. In China there is no standard of identity and because the milk is sold for its nutritive value, the price is based on its protein content (higher protein means higher prices). Therefore, there was a strong incentive for the middle-men, who collect milk from farmers, to add melamine because they get a higher price. We do not have this structure or these dynamics here, so the risk of melamine contamination in our milk supply is much lower."

Send your questions to Fixit in care of the Star Tribune, 425 Portland Av. S., Minneapolis, MN 55488, or call 612-673-7032, or e-mail fixit@startribune.com. Past columns are available at www.startribune.com/fixit. Sorry, Fixit cannot supply individual replies.