UK blood lead monitoring programme 1984-1987: results for 1985.

The Department of the Environment (DOE) has undertaken an extensive programme to monitor blood lead concentrations annually over the period 1984 to 1987 in the context of the reduction in the maximum permissible lead content of petrol from 0.4 to 0.15 g/l from 1 January 1986. The 2500 participants in the study include adults living in heavily trafficked urban areas and in occupational groups particularly exposed to petrol lead; children aged 6-7 years attending schools in heavily trafficked urban areas; and control groups of adults and children in rural areas. Blood samples (all venous) are being analysed for lead by atomic absorption spectrophotometry (AAS); considerable efforts are being made to ensure the validity of the analytical results during the period of the study. Average blood lead concentrations in 1984 and 1985 in both adults and children were generally low and were in line with levels expected on the basis of earlier surveys; only a very small proportion of individuals had raised levels. Detailed statistical analyses have confirmed that blood lead concentrations are related to a range of personal, social and environmental factors including age, sex and smoking and drinking habits. Blood lead levels in the exposed groups of adults and children were on average just under 1 microgram/100 ml lower in 1985 than in 1984, while overall changes in the police and control groups were smaller; there was, however, considerable variability in the changes in the individual surveys, particularly those of children. Levels fell in all social classes and in both categories of age of dwelling, but changes tended to be less marked in those who were older (particularly for men), smoked more, drank more or had lived for more than 15 years at their current address.