[Epidemiology of occupational disease among bricklayers in Nigeria. Effects of age and duration of contact].

Clinical and epidemiological investigations on 240 bricklayers in Nigeria show an incidence of 2,3% of cement-eczema, 2,0% of wear and tear dermatosis, and 2,8% of sensitivity against chrome. None of the examined showed a concomitant reaction to cobalt chloride. The workers with longest professional contact with cement showed the highest incidence of cement-eczema, and sensitivity against chrome. Workers of the lower age group had a higher alkali neutralization power of the skin than the older workers. The same tendency was noticed in the control tests. Generally, the African skin showed a higher alkali neutralization power than the white skin. The discussion tried to expand on the possible factors which could have influenced the observed rate of sensitization in Nigeria.