Lens opacifications detected by slitlamp biomicroscopy are associated withexposure to organic nitrate explosives

Context: Unusual cataracts (flecks) have been reported to occur at very low levels of trinitrotoluene exposure, but prevalence estimates vary widely. Cataracts have not been reported among workers in the United States exposed to organic nitrate explosives. Objectives: To determine the prevalence of unusual cataracts in a populatio n of workers in the United States exposed to organic nitrate explosives, to determine whether associations exist with reported cataract risk factors, and to determine if other eye effects (eg, retinal hemorrhage) are associat ed with exposure. Design: Cohort prevalence study. Setting A university-based ophthalmologic clinic. Subjects: Sixty-one workers From an explosives plant comprised the exposed group. The comparison group consisted of 56 workers using chemicals other t han organic nitrate explosives. Outcome Measures: The primary outcome measure was opacifications (necks) of the crystalline lens, graded clinically on a scale of 0 to 4+. Additional measures included visual acuity, applanation tonometry, and clinical evalua tion using standard examination techniques. Results: Sixty-three percent of the workers had anterior cortical lens opac ifications in a pattern of peripheral flecks. Exposed subjects were 18 time s more likely to exhibit changes than those not exposed, a statistically si gnificant association (95% confidence interval [CI], 5.0-65.0; P<.001). A s tatistically significant association with the duration of exposure was also found. Conclusions: Asymptomatic, low-grade cataracts (flecks) were identified in 53% of the workers exposed to pentolite. No other eye effects were found to be associated with exposure. Cataracts were not associated with other know n risk factors, but were associated with the duration of exposure. Biomicro scopy is widely available and useful for detecting changes in the asymptoma tic stages.