For chromate-pigment makers and users, respiratory cancer excesses have usually been found. Chromium pigments are usually hexavalent and commonly include zinc, lead, or strontium chromate. Chrome platers have also been found to have excess lung cancer. Stainless steel welding involves the greatest exposure to hexavalent chromium, as well as to nickel, and one study of chromium-nickel alloy foundry workers showed a statistically significant excess of lung cancers. It is insoluble in hot and cold water, nitric acid, and aqua regia, but reacts with dilute sulfuric acid and hydrochloric acid.
Calcium chromate occurs in the form of yellow monoclinic prisms.
It is soluble in cold and hot water and reacts with acids and ethanol. It is soluble in alcohol, ethanol, sulfuric acid, and nitric acid. When heated to decomposition, chromium trioxide emits smoke and irritating fumes. Lead chromate occurs as yellow or orange monoclinic crystals that are insoluble in water, acetic acid, and ammonia but are soluble in acid and alkali. Lead chromate, when heated to decomposition, emits toxic fumes of lead.