Risk of birth defects in a population exposed to environmental lead pollution

To investigate the relation between environmental lead and risk of birth de fects in humans, we examined the prevalence at birth of congenital anomalie s in an industrial area of northern Italy heavily polluted with lead. Throu gh a population-based registry of birth defects, we identified anomalies di agnosed during three consecutive periods characterized by decreasing enviro nmental lead exposure, 1982-1986, 1987-1990 and 1991-1995. In the lead-poll uted area, we observed an excess risk of cardiovascular defects which decre ased from 2.59 [95% confidence interval (CI) 1.68-3.82] in the first period to 1.18 (95% CI 0.62-2.06) and 0.97 (95% CI 0.57-1.54) in the subsequent p eriods. We also found an excess risk of oral clefts and musculoskeletal ano malies, with decreasing trends over time. We could not identify homogeneous patterns of temporal variation for other congenital anomalies, neither did we detect cases of neural tube defects. These results appear to support an association between severe parental lead exposure and specific birth defec ts. (C) 2001 Elsevier Science B.V. All rights reserved.