O4D.1 Longitudinal analysis of incidence of beryllium sensitization in a us nuclear workforce

The goal of this study was to evaluate trends in incidence of beryllium sensitization (BeS) and the impact of exposure regulation in a US Department of Energy (DOE) nuclear worker cohort. The 1999 DOE final rule for Chronic Beryllium Disease Prevention Program was established to accomplish three goals: reduce the number of workers currently exposed to beryllium; minimize exposures and the potential for exposure; and establish medical surveillance requirements to ensure early detection of disease. While the impact of this rule has been evaluated through observational reports, with decreases in exposure and reported cases, there have been no published studies assessing whether exposure reduction measures result in the prevention of BeS. Methods We examined the incidence of beryllium sensitization in a cohort of 6915 workers with almost 29,000 BeLPT results obtained between 1994–2018. All workers were employed at a single DOE nuclear site that implemented the DOE beryllium rule between 1999–2002. Workers were classified as BeS when they met one of the following definitions: two abnormal blood BeLPT results, one abnormal and one borderline blood BeLPT result, three borderline blood BeLPT results, or one abnormal lung lavage BeLPT result. Descriptive statistics, longitudinal analyses, and correlation analyses were utilized to evaluate the trends in incidence before and after implementation of the beryllium rule. Results Results indicated a general decrease in exposure and BeS incidence rates, though there are some years with notable increases presumably due to increased clean-up activity, where construction and decommissioning workers had opportunity for exposure from legacy beryllium operation materials that were not part of normal current production activity. Conclusion These findings provide support for the hypothesis that the DOE Beryllium Rule helps prevent beryllium sensitization. Future research will more precisely assess the relationship between beryllium exposure levels and beryllium incidence over time.