[Lead and cadmium content in deciduous incisors of children from Duisburg and Gummersbach--developing trend 1976-1988].

Shed deciduous teeth (incisors only) were collected from children (n = 199) living in Duisburg and Gummersbach (F.R.G.) in 1976 and 1988. The teeth were analysed for lead and cadmium. Considering all teeth, there was a significant of tooth lead and tooth cadmium from 1976 to 1988. The reduction was between -40 and -50% for tooth lead and -45% for tooth cadmium. Regarding tooth lead, the reduction was more pronounced in children from Duisburg, an area heavily polluted by lead and other heavy metals due to the presence of large iron and steel plants and a large lead-/zinc smelter. Teeth from the upper jaw were found to have higher lead and calcium concentrations than teeth from the lower jaw. Moreover, it was found that central incisors had higher lead and cadmium concentrations than lateral incisors. Even after the effects of jaw and tooth type had been allowed for, the reduction of tooth lead and tooth cadmium could be demonstrated. Children living in pre-war houses were found to have higher tooth lead and tooth cadmium levels than children living in post-war houses. The higher lead and cadmium burden of children living in old houses seems to be related to a higher degree of exposure to lead and cadmium via drinking water resulting from the release of these metals from old zinc-plated steel water pipes. In total, our results indicate that there has been a significant decrease of lead and cadmium exposure in West-German children since the mid-70s. The reduction of tooth lead levels parallels the decrease of blood and bone lead levels, which has been observed in previous studies.