Abstract
The health effects of exposure to lead from environmental sources are briefly reviewed and the likely benefits of removal of lead from petrol are evaluated. At current environmental levels of exposure, adverse effects of lead upon intellectual development of children are difficult to detect with certainty, but if present are extremely small. When viewed in the context of steadily increasing population IQ scores this effect appears almost negligible. The historical path of decision making over lead in petrol is traced and it is concluded that in the UK the present outcome is not necessarily the best practicable environmental option. The question is raised as to whether the considerable financial costs of removal oflead from petrol might have been better spent in other ways.