Lead exposure and amyotrophic lateral sclerosis

• Published in: Epidemiology (Cambridge, Mass.) Vol. 13; no. 3; p. 311
• Main Authors: Kamel, Freya, Umbach, David M, Munsat, Theodore L, Shefner, Jeremy M, Hu, Howard, Sandler, Dale P
• Format: Journal Article
• Language: English
• Published: United States 01.05.2002
• Subjects: Adult; Aged; Aged, 80 and over; Amyotrophic Lateral Sclerosis - chemically induced; Bone and Bones - chemistry; Case-Control Studies; Environmental Exposure - adverse effects; Female; Humans; Lead - adverse effects; Lead - blood; Linear Models; Male; Middle Aged; New England - epidemiology; Occupational Exposure - adverse effects; Surveys and Questionnaires; New England
• ISSN: 1044-3983
• DOI: 10.1097/00001648-200205000-00012

Previous interview-based studies have suggested that exposure to neurotoxicants including metals might be related to ALS. We evaluated the relation of lead exposure to ALS, using both biological measures and interviews, in a case-control study conducted in New England from 1993 to 1996. Cases (N = 109) were recruited at two hospitals in Boston, MA. Population controls (N = 256) identified by random-digit dialing were frequency-matched to cases by age, sex, and region of residence within New England. Risk of ALS was associated with self-reported occupational exposure to lead (odds ratio [OR] = 1.9; 95% confidence interval [CI] = 1.1-3.3), with a dose response for lifetime days of lead exposure. Blood and bone lead levels were measured in most cases (N = 107) and in a subset of controls (N = 41). Risk of ALS was associated with elevations in both blood and bone lead levels. ORs were 1.9 (95% CI = 1.4-2.6) for each microg/dl increase in blood lead, 3.6 (95% CI = 0.6-20.6) for each unit increase in log-transformed patella lead, and 2.3 (95% CI = 0.4-14.5) for each unit increase in log-transformed tibia lead. These results are consistent with previous reports and suggest a potential role for lead exposure in the etiology of ALS.