UK Blood Lead Monitoring Programme 1984-1987: protocol and results for 1984

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 1st January 1986. The study includes 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. The surveys are planned to cover about 1500 adults and 1000 children in total each year. Cohorts of adults are being followed, with replacement where necessary owing to moving, etc. For ethical reasons, no child will be sampled more than once, although the schools concerned will be revisited each year; children's blood is also being examined for antibodies to measles and poliomyelitis. Blood samples 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. Results for 1984 indicated that average blood lead concentrations 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. A detailed statistical analysis has confirmed the results of the EEC Blood Lead Surveys (carried out in 1979-1981) that blood lead concentrations were related to a range of personal, social and environmental factors including age, sex and smoking and drinking habits. Comparisons of any trends during the survey period in blood level concentrations in the exposed and control groups, together with results from the monitoring of sources of environmental lead should enable a broad assessment to be made of the effect of the reduction in petrol lead.