Teeth as indicators of exposure of children to lead.

indicators of exposure of children to lead. Deciduous molars, extracted from a total of 310 children aged between 3 and 10 years who resided in urban, suburban, and rural environments in Northern Ireland, were analysed for lead by atomic absorption spectrophotometry. Tooth lead content increased with age and was influenced by the nature of the donor's environment. Lead concentrations were greatest in the teeth of children in the urban group and least in the rural group, with suburban specimens intermediate. Deciduous teeth, available in quantity due to the high prevalence of dental caries, can conveniently be used as indicators ef the past exposure of children to lead contamination. The analytical method is suitable for use on a sufficient scale to enable comparisons to be made between communities. The amount of lead to be encountered in the environment has given rise to concern in several regions. This paper examines a convenient method whereby its uptake by children might be monitored. Lead behaves like calcium and most absorbed lead accumulates in bones and teeth. Lead in bone is mobile and subject to loss during the processes of remodelling and mineral withdrawal to meet physiological needs. In teeth, on the other hand, lead deposits are virtually permanent. (Strehlow and Kneip, 1969, for example, found the lead content of teeth of mature subjects to be considerably greater than that of bones.) Tooth analysis therefore can provide retrospective information concerning lead exposure, and of a kind that is not obtainable from other tissues. Needleman, Tuncay, and Shapiro (1972) found lead levels in the teeth of children in the 'lead belt' of urban Philadelphia greatly in excess of those who resided in suburban areas. This investigation was undertaken to survey the distribution of lead in the teeth of children in Northern Ireland who were living in differing environments. Materials and method Carious primary molars, extracted from children aged from 3 to 10 years who resided in the areas detailed below, were collected and separated according to their donor's age and into the following three residential groups. (1) An Urban group comprised of teeth from children who resided within a 2-mile radius of Belfast City centre. (2) A Suburban group obtained from residents in suburban areas outside the stipulated 2-mile radius. (3) A Rural group made up of specimens collected from children in country districts remote from the city (Co. Fermanagh). Any teeth showing more than minimal …