CMA: An Organic Deicer

Calcium magnesium acetate, or CMA as it is commonly know, has been the environmental deicer of choice for almost thirty years.

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During the winter months, many store shelves are stocked with a variety of deicing products, all making various claims related to their environmental friendliness. Consumers need look no further than the ingredients label to make an environmentally friendly choice. Typically the products will be either a salt (chloride) or an acid (acetate).

Salt or chloride based products are a staple of the deicer industry. Rock salt (sodium chloride) is among the best known and widely used products. Other products on the shelf will have labels saying, "Contains Primary Potassium Chloride & Secondary Urea Sodium Chloride". These are primarily fertilizers repackaged as deicers.

There is a large body of evidence demonstrating the environmental problems associated with salt based deicers. The use of potassium chlorides, for example, contribute to water eutrophication problems as they move down stream regardless of whether they are used as fertilizers or deicers. Salt may be a fairly benign chemical in most environments under limited use. However there is considerable evidence of water problems associated with excess runoff of salt based materials.

It should be noted that magnesium chloride products are commonly advertised as environmentally friendly. In comparison with other salt based deicers, the magnesium based deicers are more environmentally friendly. However, as a group, they are less friendly than the acetate group.

CMA is the most widely tested and used deicer in the acetates category. It is a natural acid that is soluble in water and it has chemical properties similar to vinegar. CMA products are used in both large scale deicing projects such as airport runways and environmentally sensitive roads, and small scale projects such as a front porch or sidewalk.

CMA and other acetate deicers are marketed under a variety of brand names. Product packaging often claim the product to be "non salt based" or "environmentally friendly". The only real way to evaluate the claim is by checking the ingredient label. Only labels with calcium magnesium acetate, CMA or another acetate based product is really the organic choice.

Price may be another quick way to identify CMA deicers on store shelves. They are approximately five times as expensive to produce as the salt based deicers. A quick scan of price tags along the store shelves will lead to the highest priced products, including any CMA products available.

© 2007. Patricia A. Michaels.