An innovative safety model and e-learning guide to working safely with beryllium throughout the industrial supply chain.

Over the past 10 years, Brush Wellman Inc., the primary beryllium producer, has partnered with the National Institute for Occupational Health and Safety (NIOSH) and others in conducting research to develop a beryllium safety model to prevent chronic beryllium disease. As the result of this research-to-practice partnership, a philosophically different worker protection model evolved based on the premise of addressing all routes and pathways of potential worker exposure. The model's fundamental principles involve keeping beryllium (1) out of the lungs, (2) work areas clean, (3) off the skin, (4) off clothing, (5) at the source, (6) in the work area, (7) on the plant site, and (8) workers prepared to work safely. Recent research by NIOSH is demonstrating that the model has reduced beryllium sensitization and lowered the risk of chronic beryllium disease in employees hired since 2001. As a result, an e-learning tool was created to enhance the communication of the model throughout the industrial supply chain.

Performance of the beryllium blood lymphocyte proliferation test based on a long-term occupational surveillance program.

OBJECTIVE: Data from surveys of the general workforce and new employees at a beryllium manufacturer were used to evaluate the performance of the beryllium blood lymphocyte proliferation test (BeBLPT). METHODS: Over 10,000 results from nearly 2,400 participants collected over 12 years were analyzed using consistent criteria to describe the performance characteristics of the BeBLPT. RESULTS: Approximately 2% of new employees had at least one positive BeBLPT result at the time of hire, and approximately 1% of new employees with no known potential occupational or possible take-home exposures to beryllium were confirmed positive (two positive results) from the time of hire. Positive results were observed in some workers within weeks or months of initial exposure, and the median time to the first positive result in confirmed positive individuals was 5 months. The prevalence of positive BeBLPT results was greatest during the first year of employment with an apparent peak in months 4-8. At least one negative or borderline/negative result was observed in 100% of new workers who underwent follow-up testing after they had been confirmed positive. There was no correlation between time of employment and an increasing prevalence of confirmed positive BeBLPT results in individual surveys; however, the cumulative incidence of confirmed positive results in subsets of workers that participated in multiple surveys increased over time. CONCLUSION: The detection of confirmed positive results in non-occupationally exposed persons, the apparent reversions of previously confirmed positive results, the identification of a positive BeBLPT peak prevalence period, and the variation in intra- and inter-laboratory test methods and interpretation should be considered when interpreting results from studies utilizing the BeBLPT, especially when considering worker-specific interventions. Additional research to refine the BeBLPT or develop a new test is needed to properly characterize the relationship between sensitization and subclinical or clinical indicators of chronic beryllium disease.

Exposure-response analysis for beryllium sensitization and chronic beryllium disease among workers in a beryllium metal machining plant.

The current occupational exposure limit (OEL) for beryllium has been in place for more than 50 years and was believed to be protective against chronic beryllium disease (CBD) until studies in the 1990s identified beryllium sensitization (BeS) and subclinical CBD in the absence of physical symptoms. Inconsistent sampling and exposure assessment methodologies have often prevented the characterization of a clear exposure-response relationship for BeS and CBD. Industrial hygiene (3831 personal lapel and 616 general area samples) and health surveillance data from a beryllium machining facility provided an opportunity to reconstruct worker exposures prior to the ascertainment of BeS or the diagnosis of CBD. Airborne beryllium concentrations for different job titles were evaluated, historical trends of beryllium levels were compared for pre- and postengineering control measures, and mean and upper bound exposure estimates were developed for workers identified as beryllium sensitized or diagnosed with subclinical or clinical CBD. Five approaches were used to reconstruct historical exposures of each worker: industrial hygiene data were pooled by year, job title, era of engineering controls, and the complete work history (lifetime weighted average) prior to diagnosis. Results showed that exposure metrics based on shorter averaging times (i.e., year vs. complete work history) better represented the upper bound worker exposures that could have contributed to the development of BeS or CBD. Results showed that beryllium-sensitized and CBD workers were exposed to beryllium concentrations greater than 0.2 microg/m3 (95th percentile), and 90% were exposed to concentrations greater than 0.4 microg/m3 (95th percentile) within a given year of their work history. Based on this analysis, BeS and CBD generally occurred as a result of exposures greater than 0.4 microg/m3 and maintaining exposures below 0.2 microg/m3 95% of the time may prevent BeS and CBD in the workplace.