S. Berardinelli, NIOSH, Morgantown, WV; C. Guglielmo, WV Workers Compensation Commission, Fairmont, WV.
The NIOSH Firefighter Fatality Investigation and Prevention Program conducts firefighter line of duty death investigations. In October 2003, two volunteer firefighters were killed and eight others were injured while operating at a silo fire. The concrete silo was located at a lumber company in rural Ohio and was filled with sawdust and wood chips. The silo was originally designed as an oxygen-limiting silo, but the company later modified the silo and operated it as a conventional silo. The fire started at the base of the silo in the auger pit from an overheated auger drive belt. Firefighters were operating on the top of the silo directing water through the cover hatch and at the base of the silo directing water into a lower hatch. The explosion that followed blew the top off the silo, killing two firefighters who where thrown 70 feet to the ground. Several other firefighters and lumber company employees were injured from falling debris. The fire marshall concluded that a backdraft occurred from ignition of the fire gases. This case study will describe the strategies used by the firefighters and how those tactics led to the explosion. NIOSH recommends that firefighters operating at oxygen-limiting silo fires develop standard operating guidelines that include: not directing water through top hatches; carefully closing all open exterior hatches; lockout the electrical service; leaving the silo closed until the fire consumes all the oxygen and self-extinguishes; and consulting the silo manufacturers for advice. It is also recommended that an exterior placard with specific silo safety precautions be used and that facilities ensure the proper operation and maintenance of their silos.
J. Zey, L. Ferguson, CMSU, Warrensburg, MO.
Recent disasters have focused the nation and the world on the need for preparedness planning and well-coordinated rescue and aid methodologies. An equally important but less well-publicized need exists for occupational safety and health (OSH) professionals with a solid foundation in practitioner skills to evaluate exposures to rescuers, recovery workers, and residents. Many OSH professionals have responded to the needs to assess exposures and safety issues resulting from hurricanes Katrina and Rita. One university has already published results of occupational assessments in the aftermath of these disasters. A dichotomy currently exists in the message sent by the leaders of OSH. Professional organizations including the American Industrial Hygiene Association, the American Conference of Governmental Industrial Hygienists, and the American Society of Safety Engineers emphasize practitioner skills, while NIOSH emphasizes research skills for academic programs receiving training grant funding. The current leadership of academic education programs emphasizes research instead of practitioner skills. This can be verified by examining the size of training grants received by Level I vs. Level II academic institutions. Yet, current research of skills and knowledge desired by employers shows they overwhelmingly want new hires to have practitioner skills. Why does this apparent conflict exit? One possible reason is NIOSH’s dependence on academicians and researchers to review academic programs. Researchers are often lacking in practitioner skills. They know research techniques but not what skills are critical to successful work as an OSH professional in field operations. They often view courses such as calculus and advanced physics as paramount, while downplaying other courses that practitioner programs value. It is paramount that the nation’s leaders work together to ensure that what employers desire in entry-level industrial hygienists is actually being taught by faculty at academic programs funded via the nations taxpayers.
A. Streifel, A. Geeslin, University of Minnesota, Minneapolis, MN; G. Nelson, Energy Conservatory Inc., Minneapolis, MN.
Airborne infection isolation (AII) rooms are needed to contain patients with airborne-spread infectious diseases. The goal of this project is to measure the leakage areas of typical isolation rooms, determine the location of the leakages, seal most of the leakages, and make recommendations for an airtightness standard that is achievable based on the measurements. The criteria for these rooms are listed in American Institute of Architects and Centers for Disease Control and Prevention documents. The CDC recommends a leakage area (or equivalent orifice area) of 72 square inches in patient AII rooms. The recently reviewed TB guideline from the CDC suggests 150 square inches per room. Because these numbers do not specify a specific differential pressure at which they occur, they are invalid as standards. One commonly used standard for airtight energy efficient homes is 2.5 square inches of leakage area per 100 square feet of building envelope surface area at 0.04 inches water column. An off-set of 125 cfm for AII rooms is currently recommended. We tested rooms utilizing duct pressurization equipment to determine room leakage area. Unsealed AII rooms tested were found to have an average of 22 square inches of leakage per 100 square feet. A room that had been sealed was tested and found to have 5.6 square inches of leakage area per 100 square feet of surface area. The leakage testing procedure involves depressurizing the room using a fan to exhaust air out of the room and vary airflow volumes. This provides data that are used to calculate room leakage area. Construction specifications must be developed to determine room leakage and room seal standards. A room validation process that verifies room seal, air change rate, filtration, and relative pressure for rooms and areas needed for infectious disease management on a periodic basis must be established.
A. Palaszewska, A. Swidwinska, S. Czerczak, Nofer Institute of Occupational Medicine, Lodz, Poland.
After the official agreement between the Agency for Toxic Substances and Diseases Registry (ATSDR), Atlanta, and the Nofer Institute of Occupational Medicine (NIOM), Lodz, was reached in September 2004, the Hazardous Substances Emergency Events Surveillance (HSEES) system was implemented in Poland. According to the set agreement NIOM, in close collaboration with ATSDR representatives, prepared required staff and computer equipment and developed proper agreements with potential reporting sources. In January 2005, NIOM started to collect and analyze information about acute releases of hazardous substances that need to be cleaned up or neutralized according to particular legislation as well as threatened releases that result in a public health action such as an evacuation. Initially, data collection within the HSEES concerned only one Polish administrative region—Lodz Voivodship. But one voivodship occurred to be insufficient for the estimation of the level and severity of chemical releases and their health and environmental consequences in Poland. That was the reason for collecting the data mostly from three administrative regions in the course of the study. Following the HSEES goals in the United States, including the reduction of the morbidity and mortality connected with hazardous substances events, the purpose of the pilot HSEES in Poland was not only to describe the spatial and temporal distribution of hazardous-substances emergencies and the morbidity and mortality experienced by employees, responders, and the general public but also in the long-term to identify the risk factors and develop strategies and action models to reduce subsequent morbidity and mortality among emergencies responders, employees, and the general public. Effects of the study comprising the chemical emergencies data collection in Poland are to be shown.
J. Utrecht, University of Cincinnati, Cincinnati, OH; A. Maier, A. Parker, Toxicology Excellence for Risk Assessment, Cincinnati, OH; C. Pittinger, BBL Science, Cincinnati, OH; J. Stewart, Environmental Health and Engineering, Boston, MA.
Toxicology and other research studies using whole animal exposures remain a cornerstone of chemical and drug safety evaluation. These studies involve potential health consequences for researchers, laboratory personnel, and animal handlers. Therefore, approaches for assessing potential health concerns associated with study protocols are needed. To meet the requirements of Institutional Animal Care and Use Committees (IACUC) and other groups, we have developed an integrated approach for risk assessment of activities associated with conducting animal research experiments. This approach brings new tools to support the traditional elements of risk assessment. First, an evergreen database structure has been developed that summarizes key hazards of toxicants or drugs used in each newly evaluated protocol. This database synthesizes and provides a critical evaluation of toxicological data for each agent. Second, a decision-logic for evaluating the potential exposure has been developed based on physical and chemical characteristics, routes of administration and use scenarios, and toxicokinetic data. Third, a qualitative approach for aligning potential hazard and exposure to corresponding control strategies has been developed. This approach has been applied to more than 250 laboratory use protocols, and offers a tool for increasing the consistency in defining hazards as well as improving the documentation of the underlying rationale for workplace control recommendations.
A. Maier, E. Hack, L. Haber, Toxicology Excellence for Risk Assessment, Cincinnati, OH; R. Savage, NIOSH, Cincinnati, OH.
For more than two decades, scientists have been touting the importance and ultimate application of biomarkers in reducing disease and protecting individuals from the harmful effects of exposure to occupational and/or environmental chemicals. While established guidelines for biomarker validation exist, methods for their implementation and case studies testing the methods are rare. This pilot study demonstrates the use of a framework for integrating complex and multifaceted data, validating biomarkers, and incorporation of the biomarkers into an occupational risk assessment for benzene. The objectives of the project were to (1) identify an occupationally relevant case study chemical; (2) develop a structure for a biomarker database that can be used to organize the diverse types of data; (3) use Bayesian analysis and regression techniques to test and validate (or discount) biomarkers along the entire exposure-disease continuum; and (4) use the biomarker database information to develop a risk assessment and compare that with a risk assessment developed using historical, traditional methodologies. A survey was developed and disseminated to 59 occupational safety and health professionals to help identify an occupationally relevant, data-rich, case study compound. Data were binned into one of the exposure-disease categories (e.g., exposure, internal dose, effective dose, early effects, mild/moderate effects, or severe effects) and entered into a customized database. A Bayesian belief network was used to validate the biomarkers by analyzing the strength of the dependencies between exposure, the potential biomarkers, and disease. Regression analysis was used to generate dose-biomarker relationships that were examined to confirm or reject biomarkers. The framework lays out an approach to consider a variety of biomarkers from the exposure-disease continuum for the enhancement of occupational risk assessment.
A. Panepinto, B. Kirchner, Proctor & Gamble, Cincinnati, OH.
More than 2,000 raw materials comprise the formulary available to the modern perfumer. Fragranced products are a part of everyday modern life. Managing fragrance materials in the industrial environment adds another dimension to the practice of industrial hygiene and occupational medicine. In addition to handling traditional hazards such as flammability or dermal irritancy, there is the issue of odor annoyance. This adds complexity to the process of assessing and managing exposure risk. While perfume raw materials generally exhibit characteristically low acute toxicity, many of these compounds in their neat form are primary or sensory irritants. In addition, the response to odors is highly individualized and unpredictable both in terms of odor character as well as the concentration at which the odor becomes objectionable. Typically 20–30% of a working population exposed to a particular fragrance mixture will define the odor as objectionable. Individual responses to odors can very greatly of a 10–12X concentration range. This diversity of responses as well as the complexity of the perfume mixture is prohibitive toward establishing a discrete exposure guideline. Over time, experience and employee surveys have enabled the development of a basic risk prediction model, which assists in the mitigation of odor annoyance risks for new perfume raw materials or mixtures. This model considers vapor pressure, odor intensity, odor character (Hedonic Tone), and the available toxicological information to determine safety and operational practices for handling that material. The management process involves a sensory experience process where employees can determine their individual sensitivity prior to introduction of these materials into the workplace supervised by a perfumer. This approach coupled with proactive training and communication with employees enables a collaborative approach to managing health and safety aspects of these operations.
A. Maier, B. Gadagbui, Toxicology Excellence for Risk Assessment, Cincinnati, OH; J. Santory, P. Ranslow, E. Becker, Consortium for Environmental Risk Management, Evansville, IN.
Occupational health professionals are often called upon to assess worker risk from potential chemical exposures in the absence of validated sampling techniques or occupational exposure limits (OELs). In such cases, alternative tools and approaches are needed to develop robust quantitative risk assessments. Such tools and approaches have been developed and applied as part of U.S. EPA’s Sustainable Futures Initiative—a voluntary EPA program with the goal of encouraging application of pollution prevention principles and the development of inherently low-hazard new chemicals. As part of the program, physical/chemical properties and production information are used in conjunction with exposure assessment models such as ChemSTEER to estimate potential exposures. Human health hazard for noncancer and cancer effects are identified based on a broad search of the literature. In many cases, data on the chemicals are very limited, and toxicology data on structural analogues and degradation products as well as quantitative structure activity relationships (QSAR) are used to develop health toxicity benchmarks in the absence of published OELs. Toxicological judgment is used to identify preferred analogs, focusing on key reactive structural groups that are likely to determine toxicity. Decision criteria for identifying potential health concerns and for selecting analogs have been developed and refined in the implementation of this program. Using these data, effect- level benchmarks are identified and combined with estimates of occupational exposure to develop risk assessments for various scenarios. This risk assessment approach allows for the rapid collection and review of datasets and identification of potential toxicological concerns early in product development and for data-poor compounds. The approach is demonstrated in the context of a case study.
A. Maier, L. Haber, Toxicology Excellence for Risk Assessment, Cincinnati, OH.
While occupational exposure limits (OELs) are not intended to be a substitute for a holistic approach to occupational health practice that includes qualitative health and safety review processes and appropriate medical surveillance, OELs have become one of the vital tools of the industrial hygiene profession. Methods for evaluating the potential impact of adverse exposures are needed, particularly for prevention of effects that result from repeated exposure and that are not manifest as easily recognized and reversible short-term effects. While one could employ strategies of best available control technology or practices to keep exposure as low as reasonably achievable, OELs provide a scientific basis for documenting that the control objectives are being met. Because of the recognized benefits of OELs, it is reasonable to expect that the community of scientists charged with developing such limits will seek continuous improvement in OEL derivation methods. This project describes ongoing scientific improvements in the methodology used by many organizations that set health-based exposure limits, and through selected case studies shows the impact to OEL values of using current risk assessment techniques. For example, the impact of tools such as benchmark dose modeling and particle dosimetry are demonstrated. An OEL development framework is presented to serve as a tool to occupational health professionals charged with developing or reviewing OELs for their workplaces. The OEL framework leads a practitioner through the OEL setting process and is intended to (1) provide a mechanism to ensure all key data sources and issues have been addressed in an OEL; (2) ensure consistent evaluation of potential critical effects; (3) increase transparency by documenting decisions; (4) highlight areas of professional judgment and potential uncertainties; and (5) increase the scientific defensibility of OELs through better documentation of the basis for OELs.
C. Dion, Y. Cloutier, S. Viau, R. Gravel, IRSST, Montreal, PQ, Canada; A. Dufresne, McGill University, Montreal, PQ, Canada; G. Perrault, Consultant, Montreal, PQ, Canada.
MOUDI is used to obtain the size distribution of beryllium aerosol. The rotating Model 110 is of special interest because it covers a wide range of aerosol sizes and can collect ultrafine particles (< 0.1 µm). The aim of this paper is to discuss problems and solutions that we have implemented as well as the still prevailing limitations of the instrument. The rotating model is currently used in a project evaluating the size distribution of beryllium aerosols in various occupational settings, first to find out if the proportion of beryllium aerosols is uniform throughout the size distribution and second to investigate the hypothesis that different chemical forms of beryllium might be predominantly found in some given sizes. The MOUDI is simple to use when one is acquainted with its operating procedures. Physically the MOUDI is bulky and is sometimes difficult to operate close to the worker. This might be problematic when comparisons need to be done with samples taken directly on workers. Problems related to the pump capacity and the flow rate adjustment have been experienced. The ability to easily achieve the two-stage pressures needed to properly operate the device will be discussed. Other parameters such as the use of the impactor with other collection substrates (ECM filters vs. aluminum substrates) for analytical purposes and the decontamination procedures of the device as validated by surface sampling will be presented. Some small modifications can make it a better device to be used in contaminated areas and more usable with different types of filters. MOUDI is just starting to be used in workplaces, and there are very few published scientific studies. It is important for research purposes to standardize all the procedures in order to compare and exchange data between different studies.
A. Stefaniak, M. Hoover, G. Day, NIOSH, Morgantown, WV; P. Breysse, Johns Hopkins University, Baltimore, MD; R. Scripsick, Los Alamos National Laboratory, Los Alamos, NM.
Elevated prevalences of sensitization and chronic beryllium disease (CBD) have been observed in workers exposed to dusts, fumes, and particles of copper-beryllium at airborne concentrations of beryllium below the current permissible limit of 2 µg/m3. Particle dissolution within lung macrophage phagolysosomes is thought to be an important source of dissolved beryllium for input to the cell-mediated immune reaction associated with development of beryllium sensitization and CBD. We used a phagolysosomal simulant fluid in a static dissolution technique to measure the simultaneous dissolution rates of copper and beryllium from a copper oxide-beryllium oxide (CuO/BeO) fume aerosol material and the dissolution rate of beryllium from a finished product BeO powder. Observed dissolution rates were normalized to values of specific surface area (SSA) to calculate a chemical dissolution rate constant (k) for each material. Dissolution of beryllium from BeO powder was biphasic (9% of total dissolved was in the initial rapid phase and the remaining 91% was in the slower long-term phase); kBe values were 8 × 10-7 g/(cm2·day) (initial phase) and 7 × 10-9 g/(cm2·day) (long-term phase). Dissolution of copper from the fume aerosol material was rapid, consisting of a single phase (100% dissolved in 4.5 days); kCu = 8 × 10-7 g/(cm2·day). Complete dissolution of copper from the fume aerosol exposed inclusions of BeO, which exhibited biphasic dissolution behavior. The measured value of SSA for the fume differed from the SSA that governed beryllium dissolution, which precludes determination of kBe. The BeO inclusions would have higher SSA than measured for the total particle sample and beryllium would therefore dissolve at a proportionally higher rate. In summary, a BeO-containing fume aerosol generated during the manufacture of copper-beryllium alloy has bioavailability properties similar to single-constituent BeO powder, which may help to explain the risk of beryllium sensitization and CBD for workers who manufacture copper-beryllium alloys.
M. Maslowski, Public Health Agency of Canada, Winnipeg, MB, Canada; J. Thom, University of British Columbia, Vancover, BC, Canada.
Laboratories traditionally did not have a primary Transmissible Spongiform Encephalo-pathy (TSE) focus. However, with the international increase of Bovine Spongiform Encephalopathy and its devastating economic and social impacts, containment laboratories specific to TSE handling are on the rise. The Canadian Science Center for Human and Animal Health (CSCHAH) is currently the world’s only high-containment facility (containment levels 3 and 4) dealing with both human and animal pathogens. The CSCHAH houses the Canadian Food Inspection Agency’s National Center for Foreign Animal Disease and the Public Health Agency of Canada’s National Microbiology Laboratory. Located in Winnipeg, Manitoba, Canada, the facility is approximately 29,200 square meters in gross area. Because of both the potential and perceived risks associated with TSE handling, a risk methodology process was used to cite a new, dedicated TSE laboratory within the existing CSCHAH. The following paper presents elements by which advancements in citing a TSE laboratory are being made. Learn the whys of establishing a laboratory specific to TSE agents. Learn the hows as the poster highlights the citing process, laboratory design, and operational practices. Program templates such as process maps, policy, and risk assessments will be shared with participants as additional handouts.
Posted May 30, 2006