Occupational lead exposure and strabismus in offspring: A case-control study

The authors conducted a population-based case-control study to investigate the association between strabismus and parental occupational lead exposure. Cases were children diagnosed with nonrestrictive strabismus between 1985 and 1986 at Baltimore, Maryland-area pediatric ophthalmology practices and clinics (n = 377). Controls were matched for age and hospital of birth (n = 377). Jobs held by parents were assessed for lead exposure by industrial hygienists. The time window for lead exposure was defined as the period from conception through age 9 months. The unadjusted odds ratio for maternal lead exposure and the esotropic form of strabismus was 2.6 (95% confidence interval (Cl) 0.4-27). Unadjusted odds ratios for paternal occupational lead exposure and esotropia were 1.0 (95% Cl 0.5-2.1) for low exposure, 2.1 (95- Cl 0.9-5.3) for moderate exposure, and 1.2 (95% Cl 0.4-3.3) for high exposure. The study results suggest the possibility of a weak association between paternal lead exposure and strabismus in offspring. Am J Epidemiol 1991 ;133:351-6.