J. Xing, The Center Hospital of Xihan Coal & Power Co., Taiyuan, China; W. Chen, F. Wang, School of Public Health, Tongji Medical College, in Huazhong University of Science and Technology, Wuhan, China.
This study was designed to understand the role of heat shock protein in protecting miners from coal dust exposure or describing damage from coal dust exposure. The objective was to explore the role of heat shock proteins Hsp27, Hsp72, and Hsp73 in the development of lung cancer in coal miners. Fifty-one coal miners suffering from lung cancer were selected as cases, and 99 healthy coal miners of the same age, employed in same coal mine, were selected as controls. The expressions of Hsp27, Hsp72, and Hsp73 in peripheral blood lymphocytes were determined for all subjects. Possible risk factors of lung cancer were analyzed for these coal workers. In comparison to the controls, both small and large stress-inducible Hsp27 (16.94±2.73) and Hsp72 (17.93±4.63) expressions of peripheral blood lymphocytes for lung cancer cases were significantly smaller than those in healthy coal miners (Hsp27: 22.94±10.21, and Hsp72: 23.12±12.61, P<0.01). No statistical difference was observed for Hsp73 between the two groups. The risk factors for lung cancer were high cumulative coal dust exposure, the amount of smoking, and decreased Hsp27. Long and high exposure to coal dust could reduce stress response ability. The Hsp27 and Hsp72 expressions in peripheral blood lymphocytes decreased in coal miners who developed lung cancer. Hsp27 may play a crucial role in preventing coal dust overexposure as well as lung cancer development.
D. Crane, OSHA, Sandy, UT.
Combining industrial health and safety expertise with its physical measurements knowledge, OSHA’s Salt Lake Technical Center provides expert evaluation of processes, accidents, and failures in support of OSHA inspections. A number of recent investigations of laboratory materials failure highlight the techniques used to determine the cause of fatal accidents and how they relate to existing OSHA regulations in various industries. This type of analysis is especially useful where there are no witnesses to an accident and the compliance officer needs help to determine the cause.
J. Hartle, Intel Corp., Santa Clara, CA.
Our company’s High Volume Manufacturing (HVM) Chemical Review Forum developed out of a need to anticipate future product manufacturing issues during the research and development (R&D) phase. The thorough evaluation of chemicals during the R&D phase is critical to prevent wasted time and resources in selecting chemicals that may encounter regulatory issues or factory specific issues downstream. The challenges we faced in developing this forum were designing the meeting format and tools to fit our needs, enlisting the correct stakeholders, and obtaining the production chemical list. The resulting meeting format is a core team of environmental health and safety (EHS) professionals that regularly meet to complete the initial review of each chemical. The team consists of industrial hygienists, environmental engineers, toxicologists, and a representative from our factory materials organization. The subsequent meetings involve the core team and EHS representatives from the sites that will receive the technology. It is these sites’ responsibility to review the chemicals and identify potential obstacles due to local regulations or factory-specific issues. Our current HVM forum has been used for two new product lines. Its success can be measured by the reduction in last-minute regulatory issues at the manufacturing sites, heightened and earlier assurance of adequate EHS controls for new chemicals, and improved communication with stakeholders. The improved communication has increased EHS’s ability to obtain the proprietary list of production chemicals. It has also resulted in positive feedback from the EHS staff at the manufacturing sites receiving the technology, the factory materials organization, and factory engineers selecting production chemicals.
F. Akbar-Khanzadeh, S. Milz, A. Ames, University of Toledo, Toledo, OH.
A field laboratory was set up to simulate concrete surface grinding using hand-held angle grinders in an enclosed workplace equipped with a general ventilation system. The effectiveness of wet grinding (wet dust reduction method) and ventilated-grinding (local exhaust ventilation method) in reducing the levels of silica dust (crystalline) and respirable suspended particulate (RSP) matter was compared to conventional grinding (no dust reduction method). The effects of the general ventilation on the levels of air contaminants were also studied. A total of 52 personal samples and 17 area samples (10 inside and 7 outside the laboratory) was collected during concrete grinding. In the laboratory without general ventilation, the mean concentrations of silica dust and RSP matter in personal samples were, respectively, 107 and 1082 mg/m3 during conventional grinding; 1.40 and 17.4 mg/m3 during wet grinding; and 0.16 and 2.17 mg/m3 during ventilated grinding. With the general ventilation, the mean concentrations of silica dust and RSP matter were reduced to 44.2 and 383 mg/m3 during conventional grinding; 0.52 and 7.77 mg/m3 during wet grinding; and 0.15 and 1.82 mg/m3 during ventilated grinding. The results of this study suggest that conventional grinding generated very high levels of silica dust and proportionally high levels of RSP matter. Wet grinding was effective in reducing the mean concentrations of silica dust and RSP matter more than 70x. Ventilated grinding was even more effective, reducing the mean concentrations of silica dust and RSP more than 400x compared to conventional grinding.
L. McGowan, U.S. Department of Labor, OSHA, Washington, DC.
WITHDRAWN
U. Perleberg, Georgia Tech Research Institute, Atlanta, GA.
The objective of this study was to evaluate industry compliance with the regulatory exposure limits for formaldehyde established by OSHA. One hundred and thirty-three funeral homes throughout Georgia were included in this study. The study found that 52% of companies had not completed any formaldehyde monitoring or had sampled incorrectly. Where records were available from the funeral home, previously collected formaldehyde exposure data was gathered for secondary data analysis. Funeral homes that had not conducted monitoring prior to the study were required to complete the monitoring and to provide the results to the research staff. Using organic vapor monitor passive badges, breathing zone air samples were collected by funeral home employees while they conducted embalming activities on human remains. Two types of samples were collected during an embalming: a 15-min short-term exposure limit (STEL) sample and a permissible exposure limit (PEL) sample. The STEL samples (n=239) averaged 1.5 ppm (ranging from 0-36 ppm), and the PEL samples (n=182) averaged 0.17-0.25 ppm (ranging from 0-3.27 ppm). Based on the self-reported results, 13.5-15.0% funeral homes were found to exceed either the PEL or the STEL. An additional 4.5-6.1% funeral homes reported results exceeding the OSHA action level. Of the funeral homes involved in this study, 18.0% to 21.1% exceeded the OSHA regulatory limits. These results suggest that Georgia funeral homes would benefit from additional training on the importance of formaldehyde monitoring in the workplace, with an emphasis on correct sampling techniques, to achieve compliance with OSHA regulations. In addition, based on the exposure levels reported by the funeral homes, a closer look at proper ventilation design is warranted.
M. Linnainmaa, M. Mäkinen, S. Metsärinne, J. Kangas, Finnish Institute of Occupational Health, Kuopio, Finland; P. Kalliokoski, M. Veteli, University of Kuopio, Kuopio, Finland; J. Säntti, Finnish Institute of Occupational Health, Helsinki, Finland.
Workers’ exposure to refractory ceramic fibers (RCFs), used to replace asbestos in the thermal insulation applications, was evaluated by measuring airborne RCFs in two steel plants, three foundries, and in a repair shop. The measurements were conducted both during normal production tasks and during the service breaks in the steel plants when oven insulations were changed. RCF samples were collected onto polycarbonate filters at the breathing zones of 55 workers and at 29 stationary sites, to study the spreading of the fibers to working environment. The fibers were identified with an energy dispersive X-ray analyzer, and counted with a scanning electron microscope with 1000x magnification. During the normal production, the levels of RCF were usually below the new Finnish occupational exposure limit (OEL) of 0.2 f/cm3 in the breathing zone samples, both in the steel plants (<0.01-0.29 f/cm3) and in the foundries (<0.01-0.09 f/cm3). The concentrations were very low (<0.02 f/cm3) at stationary sampling sites. To the contrary, high concentrations were measured during the maintenance breaks in the steel plants and the repair shop. During these service and repair tasks, the OEL was clearly exceeded in almost all the breathing zone samples, the highest concentration being 14.2 f/cm3. On the other hand, the concentrations at stationary sites outside the furnace were low (<0.01-0.07 f/cm3). The study confirmed that workers handling RCF materials may be exposed to high levels of fibers, especially during removal and installation of thermal insulation. Therefore, the exposure should be controlled by effective local exhausts and ventilation, and personal protective equipment should be used always when RCF materials are handled. When technically possible, carcinogenic RCF should be replaced by alkaline earth silicate fibers, which are more soluble in vivo and therefore are not classified as carcinogenic.
A. Siert, S. Woods, Xcel Energy, Denver, CO; K. Blehm, Colorado State University, Fort Collins, CO; H. Beaulieu, Industrial Hygiene Resources, Boise, ID; P. Bigelow, Institute for Work & Health, Toronto, ON, Canada.
Welding industrial hygiene surveys and metal fume exposure assessments were conducted over an 11-year period at 13 electric power generation plants in two states. Along with air monitoring data, survey information on (2) processes, consumables, base metals, and environmental conditions, and (2) use of exposure reduction controls was used to characterize exposures to total welding fume and its components, including manganese and hexavalent chromium.
F. Boelter, C. Simmons, CIH, Boelter Associates, Inc., Park Ridge, IL.
Electric arc welding is a common process and the U.S. Bureau of Labor Statistics estimates that welding, soldering, and brazing workers accounted for about 429,000 jobs in the United States in 2004. Shielded metal arc welding (SMAW), or stick welding, is the main electric arc welding process. The complex mixture of compounds that comprise fume, including metallic oxides, gases, silicates, and fluorides, are often associated with the flux coating on electrodes. Data generated during this field study was analyzed to determine the relationship between arc time and field derived generation rates for total particulate (TP), iron (Fe), and magnesium (Mn). Welding fume samples were collected under field conditions inside a boiler room and in an outdoor breezeway. Welding arc time ranged from 3.5 to 4.2 min for the 15-min short-term samples and varied by time period from 17.5 to 37.5 min for long-term personal samples. This correlated to a 20% to 37% arc time overall, for usage of both E6010 and E7018 electrodes. The short-term samples were used to assess trends. The average inside helmet, 15-min personal sample results in the boiler room were: TP - 5.00 mg/m3; Fe - 0.67 mg/m3; and Mn - 0.10 mg/m3. In the breezeway they were TP - 3.73 mg/m3; Fe - 0.58 mg/m3; and Mn - 0.12 mg/m3. Ventilation in the boiler room was characterized using an anemometer and sulfur hexafluoride tracer gas. A two-zone mass balance model was applied and used to determine the generation rate. Arc time was not found to be a good predictor of fume generation rate or airborne concentration in the breathing zone. Various reasons were examined including the fact that actual arc time is generally less than 25% for an 8-hr workday.
H. Beaulieu, C. Brown, J. Brown, Industrial Hygiene Resources, Boise, ID.
Phenyl mercuric acetate (PMA) has been used historically as a catalyst in polyurethane systems. In the 1950s-1970s, PMA was used as a catalyst in the 3M, Tartan brand, polyurethane flexible floors that were commonly installed in gymnasiums of schools. Mercury vapor is released into air above the surface of these floors. Sampling mercury (Hg) in bulk flooring material and mercury vapor in air was conducted in nine Idaho schools in spring 2006. These evaluations were conducted in response to concerns by school officials that the floors could contain mercury and could release the mercury vapor into the air, presenting a potential health hazard for students, staff, and visitors. In summer 2006, controlled abatement was conducted in one school, consisting of the removal of the mercury-bearing, flexible gym floors (~9000 s.f. total). The controlled abatement consisted of the following: containment of the work area with negative air technology; worker protection (including mercury specific training); use of personal protective equipment; biological and exposure monitoring; and environmental protection (including proper disposal of mercury-bearing, hazardous waste material).
P. Corcoran, Cal/OSHA, Sacramento, CA.
It appears from a recent string of Cal/OSHA inspections that the use of styrene-based polyester and vinyl ester resin systems is increasing in the fiber glass reinforced plastics (FRP) industry. Styrene exposures can lead to central and peripheral nervous system effects. These resin systems and the accompanying hazards are found in a wide range of manufacturers, including makers of swimming pools, hot tubs, sporting equipment, showers, and yachts. The thermoset resins are applied in a mixture containing a large proportion of styrene (up to 50% by weight), and are catalyzed with methyl ethyl ketone peroxide (MEKP), a highly reactive and unstable compound. The increasing preference for styrene-based resins is being driven by a desire to improve strength and durability, decrease costs, and avoid some of the well-documented hazards associated with other resin systems and their catalysts. Unfortunately, these styrene-based resin systems introduce problems of their own. This presentation focuses on several case studies of employers’ use of styrene-based resin systems and the hazards identified during Cal/OSHA investigations. Air sampling for styrene in these investigations identified significant overexposures of workers. Cal/OSHA permissible exposure limits for styrene (50 ppm) and short-term exposure limits (100 ppm) were routinely exceeded. Each case presented a similar pattern of violations. Styrene overexposures were accompanied by failure to monitor the styrene exposure, an inadequate respiratory protection program, an inadequate hazard communication program, lack of effective engineering controls, ineffective personal protective equipment, and uncontrolled dermal exposures. In addition, significant hazards associated with the use of an MEKP catalyst were present, and work practice controls needed for handling this reactive substance were lacking.