Does lead play a role in the development of chronic renal disease?

For many decades lead has been considered to be one of the causes of chronic renal failure. A critical analysis of the available epidemiological studies, however, indicates that the relationship between lead exposure and the development of chronic renal failure is largely circumstantial. Indeed, several aspects remain obscure: relative and absolute risk, risk factors, duration of exposure, pathology and diagnostic criteria. Moreover, methodological problems related to cohort selection (i.e. the 'Healthy worker effect'), study design and definition of renal dysfunction may limit the value of the epidemiological results. Although the available literature suggests that lead may play a direct or contributory role in the development of chronic renal failure it is concluded that additional detailed epidemiological studies are required.