Cobalt and nickel content of Asian cements

The total cobalt and nickel concentration of 11 brands or Asian cement ranged from 8.1 to 14.2 μg/g and 28.5 μg/g, respectively. These metals exist mainly as insoluble suits; the water-soluble concentration of cobalt and nickel in the cements ranged from 039 to 0.65 μg/g and from 0–1.2 μg/g. respectively. 1.5% (4/272) of construction workers in a prefabrication construction factory had cobalt sensitivity. All had allergic contact dermatitis from chromate in cement. No worker and isolated cobalt sensitivity and cement dermatitis. It appeared that sensitization to cobalt in cement occurs only Secondarily to an existing cement dermatitis 1.8% (5/272) workers had nickel sensitivity: 2 with allergic contact dermatitis to nickel in their watches. 2 were asymptomatic and I had allergic contact dermatitis to chromate and cobalt in content. The low prevalence of cobalt and nickel sensitivity from cement was probably related to the low concentration of soluble cobalt and nickel salts in the cement. However, these insoluble salts can form soluble completes with body fluids on eczematous skin and sensitize the skin.