H. Burge, Environmental Microbiology Laboratory Inc., San Bruno, CA.
Risks associated with fungal aerosols can be divided into three topics: risk of exposure, risk of health effects, and risk management. For estimating risk of exposure, one must document that unusual exposure is occurring in interiors open to the outdoor aerosol, or document that any exposure is occurring in interiors where outdoor aerosol penetration is prevented. For the former, comparison with control sites — especially the outdoors — is essential. For the latter, one must establish a minimum exposure concentration, since proving the negative case is not possible, and, given the ubiquity of fungal spores, achieving a zero level is unlikely. Estimating the risk of health effects is more difficult, since there are no available dose/response data to be used for guidance. Epidemiological studies are, of course, possible and helpful. Deciding whether an individual is actually experiencing symptoms related to specific exposures relies generally on specific immunological testing (skin or other IgE tests for allergy/asthma) or specific physical tests for hypersensitivity pneumonitis. In the former case, concentrations of the agents are relatively unimportant. In the latter, high concentrations of antigen are apparently necessary but rarely found. Risk management involves preventing unusual exposures and minimizing any exposure for immunocompromised individuals. These can be accomplished by removing individuals from an environment that is clearly related to their illness (using the tests described above), removing the exposure reservoirs (usually done regardless of risk documentation), or by the use of personal respiratory equipment.
H. Burge, Environmental Microbiology Laboratory Inc., San Bruno, CA.
While evidence is increasing that exposure to Mycobacterium aerosols may result in hypersensitivity pneumonitis (HP), the factors that lead to the presence of this ubiquitous microorganism in machining coolants remain unknown. In fact, the management of microbial populations in machining coolants is far removed from science. Also, the patterns of exposure to any machining fluid aerosol that lead to HP are unknown. Thus we cannot use fluid management to prevent exposure to agents that could lead to HP. Outbreak investigations have not yielded data that would allow prediction of conditions that could lead to Mycobacterium infestation of fluids. Until these predictions are possible, control of Mycobacterium aerosols will have to depend on unproven chemical treatment or on mist control. We have developed a protocol that documents the chemical characteristics of used fluid and the concentration of microbes (culturable and countable), and that specifically allows counting of Mycobacterium cells. Included are measurements of pH, metals, and organic carbon. This protocol allows a determination of the prevalence of Mycobacterium and collects some preliminary data on the factors that may control its growth. We propose that industrial hygienists interested in machining coolants work with us to expand this protocol based on their knowledge and experience and collaborate in a broad study of machining coolants that could lead to the development of predictive models for the presence of Mycobacterium and other unusual microorganisms.
W. Davis, G. Utter, A. Fong, B. Brooks, J. Debroy, M. Marnell, R. Schimke, W. LaComb, S. Kreiser, IBM, Boulder, CO.
An environmental chamber testing study was undertaken to characterize the long-term emissions of volatile organic compounds (VOCs) from a high-performance mainframe server. The objective of the study was to expand the current database on VOC emissions from information technology (IT) and office equipment products, which is limited to data collected from smaller products (personal computers, monitors, and personal or small work-group printers) and short testing durations (96 hr or less). A mainframe server was tested in a 101 m3 environmental chamber, and air samples from the chamber were collected on days 1, 31, 65, 94, and 120 of the test. Emitted VOCs were identified by gas chromatography-mass spectrometry and quantified by comparison to standard calibration curves. Formaldehyde and acetaldehyde were determined by 2,4-Dinotrophenylhydrazine (DNPH) derivatization high-performance liquid chromatography. Ozone emissions were measured by a Dasibi ozone monitor. Emissions rates were measured for five groups of chemicals (alcohols, aldehydes, arenes, chlorinated compounds, and miscellaneous aliphatic hydrocarbons). The rates of emissions decayed over the 120-day test period for 16 of the 20 identified chemicals, with the largest percentage decrease generally found between sampling day 1 and day 31. Chamber air samples were below the limits of quantitation for the majority of the VOCs by sampling day 120. Estimated room VOC concentrations calculated from chamber emissions rates were below established occupational exposure limits and other health-based levels. A quantitative risk assessment was conducted comparing risks, assuming no decline in the rates of emissions of VOCs from the server to risks based on the measured decay rates. Results of the present study indicated that risks calculated using exposure assessments based on emissions rates measured over the commonly used 96-hr test period can markedly overestimate the potential health risks associated with VOC emissions from IT and office equipment products over the useful life of the products.
C. Torres, Intel Corp., Colorado Springs, CO; S. Kinsler, Intel Corp., Hillsboro, OR.
This presentation will outline the approach taken to control risk associated with new chemical introductions with limited or no environmental health and safety (EHS) data. Over the past several years, it has become increasingly difficult for EHS professionals to assess and control risk associated with new chemical and material introductions. A primary reason for this difficulty is the accelerating trend of chemical requests with limited or no toxicological/chemical data. To address the problem, a multidisciplinary EHS team was chartered to address the problem by developing and implementing improvements to existing chemical approval guidelines and processes. The team’s scope and objectives were to: (1) develop and implement guidance and tools for approvers for assessing chemicals with limited or no data; (2) define an appropriate level of engineering and administrative (personal protective equipment) controls; (3) clarify roles and responsibilities of site EHS chemical approvers, toxicologists, and others; (4) define minimum data and documentation expectations of chemical and material suppliers; and (5) define data needed for technology development and high-volume manufacturing applications. To address the problem, a tool was developed to provide a unique and elegant solution that accomplished the following: (1) ensured protection of employees and environment when using chemicals with limited or no data; (2) promoted consistent control strategies to be used companywide for chemicals with limited or no data; (3) provided EHS controls guidance to exceed the standard level of care for chemicals with limited/no data; and (4) documented the business processes used to manage and control chemicals with limited/no data.
The tool guides the approver through quantifying the available data, inventorying chemical characteristics affecting hazard potential, and categorizing the chemical based on available data and characteristics. Once the chemical is categorized, recommendations on appropriate controls are provided by category type. Testing and use has demonstrated the tool is highly effective at providing appropriate control recommendations, driving consistent outcomes, and documenting the process.
D. Venturin, Unifrax Corp., Niagara Falls, NY.
The refractory ceramic fiber (RCF) industry, through the Refractory Ceramic Fiber Coalition (RCFC), has partnered with various agencies since the early 1990s to facilitate the rulemaking and standard-setting process. Through partnering, agencies benefit by exposure to industry research scientists and the latest scientific studies on epidemiology, toxicology, risk assessment, exposure monitoring, and product stewardship efforts. The industry benefits from an accessible rulemaking process. RCFC finds that regulatory partnering is welcomed and viewed by agencies as an enlightened response to a mandate for workplace safety. In the early 1990s, the RCF industry partnered with the Environmental Protection Agency under a five-year consent agreement program to monitor fiber concentrations in manufacturer and customer facilities. This program was renewed in 2002 with OSHA as a voluntary product stewardship program (PSP 2002). PSP 2002, also a five-year plan, was recently renewed and continues monitoring efforts and other activities designed to reduce overall exposure. This ongoing partnership has effectively improved workplace safety across the industry. In 2005, the industry worked with the Ontario Ministry of Labour to provide information on PSP 2002, monitoring data, and scientific studies to set an occupational exposure limit (OEL) for RCF. As a result, the new OEL is identical to RCFC’s recommended exposure guideline (REG). This outcome pleased both industry and government: RCFC personnel were impressed with the transparency of the process, and agency personnel were impressed by the volume and quality of data provided by the industry.
The industry recently partnered with NIOSH to provide input for the 2006 criteria for a recommended standard for RCF. While NIOSH is not a regulatory agency, the industry intends to pursue additional opportunities for partnering with NIOSH to further workplace safety.
A. Finkel, UMDNJ, Piscataway, NJ.
OSHA maintains a database of personal and area air samples taken at U.S. workplaces since 1979, containing analytic results for more than 1600 different substances. Various investigators have studied portions of this database, generally confining their inquiries to a single substance of interest or a single industry sector, and have provided important insights about time trends in exposure conditions, the influence of covariates (such as company size and compliance history) on exposures, and the feasibility of lowering exposure limits on controversial chemicals. As the first phase in a series of investigations of the entire database, this presentation will report on general findings about the spectrum of occupational exposures over the past 25 years, focusing on insights regarding OSHA’s chemical sampling, occupational health enforcement, and rulemaking programs. Among other inquiries, statistical analysis of the OSHA database will shed light on these topics: (1) trends in the number of air samples OSHA has taken over time, both in total and for approximately 20 substances of intense scientific interest; (2) the relationship between the fraction of all measurements for these substances in a given year that are above the applicable mandatory or recommended exposure limit and the number of samples taken for that substance in the following year (as a rough indicator of how well OSHA targets its sampling resources); (3) the hypothesis that average workplace concentrations of regulated carcinogenic substances should be roughly 1000x greater than the ambient concentrations measured by federal and state EPA monitoring networks; and (4) a tentative risk-based ranking of which unregulated substances should be of highest priority for future OSHA rulemaking, based on the extent of exposure combined with dose-response information from the literature.