The level of pH in these buckets becomes dangerous after washing as little as one tool. Even clean, running water does little to remove residual alkali contaminants. Allegic Contact Dermatitis Allergic contact dermatitis is caused by absorption of particular elements or compounds into the skin. Water-soluble hexavalent chromium is one of these elements and is present in small amounts in Portland cement. Some of it comes from cement's raw materials, some from the cement manufacturing equipment.
Hexavalent chromium is a know allergen to some people.
Over a period of weeks, or months or years, hexavalent chromium can be gradually absorbed into the skin. Once the body becomes sensitized to the chrome, even a very small amount can trigger a severe skin reaction. Once a concrete worker is sensitized, chances are he or she will be sensitized for his or her entire life. Chromium-sensitized concrete workers are strongly urged to leave the trade.