Health Hazard Evaluations (HHEs)

(2001) Oklahoma City Community College, Oklahoma City, Oklahoma. (Click to open report)
The National Institute for Occupational Safety and Health (NIOSH) received a request for a health hazard evaluation from employees at the Oklahoma City Community College Bookstore on August 13, 2001. Employees were concerned that the temporary location of the bookstore in the school's gymnasium was exposing them to excessive noise from activities occurring in the gymnasium. Following a cheerleading camp held in the Summer of 2001, one employee experienced pain and ringing in her ears from the ... (Click to show more) The National Institute for Occupational Safety and Health (NIOSH) received a request for a health hazard evaluation from employees at the Oklahoma City Community College Bookstore on August 13, 2001. Employees were concerned that the temporary location of the bookstore in the school's gymnasium was exposing them to excessive noise from activities occurring in the gymnasium. Following a cheerleading camp held in the Summer of 2001, one employee experienced pain and ringing in her ears from the yelling and screaming by the participants. The bookstore employees were also concerned about mold and dust in the bookstore that they felt resulted in additional sickness for the workers. A NIOSH investigator visited the campus bookstore on October 17-19, 2001, to make noise measurements in the bookstore while a Fall Break Camp was held in the gymnasium. Personal and area noise samples were obtained over two full days in the bookstore. The NIOSH investigator also made visual observations of the work area, interviewed bookstore employees, and spoke with representatives of the College's physical plant about the operation of the heating, ventilating, and air conditioning (HVAC) system and the condition of the gymnasium's roof. The results of the personal noise sampling revealed time-weighted average (TWA) noise levels that were 6% or less of the daily allowed noise dose according to the evaluation criteria to prevent occupational hearing loss from noise. The area noise samples showed that the activities in the gymnasium did interfere with communications for the employees of the bookstore, particularly the voices of the children in the day camp. The temporary wall constructed to isolate the bookstore was ineffective in reducing the noises emanating from the gymnasium. Also, the housekeeping conditions observed in the bookstore were poor, with dust located throughout the space. The personal noise measurements made during the two days of the Fall Break Camp revealed that employees of the bookstore are not at increased risk of occupational hearing loss as a result of their noise exposures. However, the interference with daily activities at the store was confirmed by the area noise samples. Visual observations made during the site visit found large amounts of dust throughout the bookstore and an area on the southeast wall that had visible staining from a previous roof leak. Recommendations are made in the report on the construction of a more efficient, sound-attenuation wall and on improving general housekeeping practices. (Click to show less)
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(2001) Robinson Run Mine, Shinnston, West Virginia. (Click to open report)
On December 6, 1999, NIOSH received a confidential health hazard evaluation request regarding possible health effects in workers exposed to Solcenic HL hydraulic fluid at the Robinson Run Mine in Shinnston, West Virginia. Solcenic HL emulsion is used in the closed loop hydraulic system that pressurizes the piston-driven roof supports in the longwall section of the underground coal mine. Solcenic HL is a proprietary formulation of mineral oil, alcohol, poly glycol, inorganic salt, organic acid sa... (Click to show more) On December 6, 1999, NIOSH received a confidential health hazard evaluation request regarding possible health effects in workers exposed to Solcenic HL hydraulic fluid at the Robinson Run Mine in Shinnston, West Virginia. Solcenic HL emulsion is used in the closed loop hydraulic system that pressurizes the piston-driven roof supports in the longwall section of the underground coal mine. Solcenic HL is a proprietary formulation of mineral oil, alcohol, poly glycol, inorganic salt, organic acid salt, and a triazine biocide. It is similar in formulation to emulsifiable metal working fluids which have been associated with respiratory disorders, work related asthma, and allergic and irritant skin disorders (NIOSH, 1998a). We conducted telephone and on-site interviews with miners who were concerned that exposures to Solcenic HL emulsion might be putting them at risk for sinusitis, rhinitis, adult onset occupational asthma, and dermatitis, especially during periods of atypical exposure such as when working around large spills. We administered a medical-work history questionnaire on October 18, 19, and 20, 2000. Its purpose was to assess the prevalence of various respiratory and skin disorders and symptoms in relation to possible sources and pathways of exposure, especially to Solcenic HL emulsion. The questionnaire requested demographic data, a brief work history, possible workplace exposures, and included questions designed to identify individuals with sinusitis (nasal), breathing, and dermal (skin) disorders. Because Solcenic HL emulsion is only used at the longwall, miners were grouped as either "longwall miners" (potentially exposed individuals) or "nonlongwall miners" (minimally exposed or nonexposed individuals). The minimally exposed group includes some miners who occasionally assisted with relocation and maintenance of the longwall equipment. There were 85 respondents out of 250 current employees representing 100 percent (33/33) of the longwall workforce and about 25 percent (52/250) of the "nonlongwall workforce." The prevalence of self-reported sinus or nasal symptoms that required medical attention was 24 percent (8/33) among longwall miners versus 48 percent (24/52) among miners whose primary work areas were other areas of the mine. Because the rate of symptoms was higher in the nonexposed group, there does not appear to be a positive relationship between the routine use of Solcenic HL emulsion and nasal/sinus symptoms. However, self-reporting bias is a possible explanation for the higher rate of symptoms in the nonexposed group; those without symptoms may not have been motivated to respond to the questionnaire. Exposure misclassification is another possible explanation; some of the "minimally exposed workers" may have experienced acute exposures to Solcenic HL emulsion during their temporary assignments to work on the longwall. The prevalence of self-reported adult onset asthma was 6 percent (2/33) among longwall miners and 6 percent (3/52) among nonlongwall miners [For comparison, McWhorter et al. (1989) estimated the prevalence of active asthma among U.S. adults to be 2.6 percent.] Of the five self-reported cases, two worked on the longwall, two worked throughout the mine including the longwall, and one worked on a continuous mining section. Four of the five, including the continuous mining section worker, reported that "Solcenic" or "hydraulic fluid" exacerbated their asthma symptoms. Self-reporting bias and misclassification are concerns, and we can neither establish nor rule out a relationship between exposure to Solcenic HL emulsion and self-reported adult onset asthma. The prevalence of self-reported dermal symptoms that required medical treatment was 21 percent (7/33) for longwall miners and 25 percent (13/52) for other miners. Once again, self-reporting bias and misclassification are concerns, and we can neither establish nor rule out a relationship between exposure to Solcenic HL emulsion and self-reported mine-related dermatitis. Concurrent with obtaining and evaluating the medical-work history information, we collected and analyzed samples of the bulk Solcenic HL, the Solcenic HL emulsion, emulsion leakage from the mine floor, and area samples of the mine air to characterize the work environment. We identified two agents that warranted further investigation. The first agent was formaldehyde (a breakdown product of the triazine biocide in Solcenic HL), which is associated with upper respiratory and dermal irritation and sensitization and is considered by NIOSH to be a potential occupational carcinogen. The second agent was microbials (i.e., bacteria and fungi) from the shearer sprays and the mine air, which are also associated with upper respiratory symptoms, adult onset asthma, and dermal symptoms. The maximum concentration of formaldehyde in air during our sampling program was 0.027 parts per million (ppm). This is two orders of magnitude below the MSHA Permissible Exposure Limit (PEL) of 2 ppm, one order of magnitude below the American Conference of Governmental Industrial Hygienists (ACGIH) 2000 Threshold Limit Value (TLV) of 0.3 ppm, and similar in magnitude to the NIOSH Recommended Exposure Limit (REL) of 0.016 ppm. Although the PEL is the legally enforceable limit, employers are encouraged to follow the most protective criterion among the PEL, TLV and REL. The NIOSH REL for formaldehyde is a qualitative value based primarily on the analytical limit of detection. There were no large spills of Solcenic HL emulsion during our sampling program, but we believe that formaldehyde concentrations in air during atypical events have the potential to exceed the MSHA PEL. We evaluated the possibility that triazine from spillage of Solcenic HL emulsion might adsorb onto or absorb into rockdust and be converted to formaldehyde after inhalation and deposition of the dust in the respiratory tract. The amount of triazine that might be adsorbed onto or absorbed into rockdust that becomes aerosolized and inhaled was found to be negligible. In our microbial evaluation, we sampled the Solcenic HL emulsion from the hydraulic lines and found no bacteria and four colony forming units per milliliter (CFU/ml) of basidiomycetes and 2 CFU/ml of an unidentified fungus. These low levels of fungi in the emulsion could have originated from contact with equipment surfaces during sampling. We also sampled the shearer spray water for microbial content and found several species of bacteria that may be pathogenic or that are indicators of pathogenic potential. The shearer spray is fed by surface water that passes through a coarse sand filter before being sprayed to suppress dust from the shearer. Based on good public health practice, we recommend additional filtration or treatment for the shearer sprays. We sampled the air on June 13-14, 2000, for fungi and bacteria. Fungi concentrations in the mine ranged to 9.6 x 103 CFU per cubic meter of air (CFU/m3) and bacteria concentrations ranged from below the level of detection to 1.4 x 105 CFU/m3. The predominant fungal genera outside the mine was Cladosporium and the predominant fungal genus inside the mine were Cladosporium, Penicillia, and basidiospores. The bacteria found in the mine air included Actinomycetes, Rhodococcus, Actinobacter, and Pseudomonas. Although these are ubiquitous environmental microbials, exposures to fungi and bacteria have been associated with sinus/nasal and asthmatic symptoms in susceptible individuals. In conclusion, the hypothesis that miner exposures to Solcenic HL emulsion caused or exacerbated the reported health effects in some workers can neither be established nor ruled out. Exposure to formaldehyde is possible during atypical events such as large spills. Pathogenic microbial species were also found in both the shearer spray and the mine air, but their relationship to the reported symptoms is unknown. The following recommendations are based on information derived from studies of m... (Click to show less)
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(2001) Special Metals Corporation, Princeton Powder Division, Princeton, Kentucky. (Click to open report)
The National Institute for Occupational Safety and Health (NIOSH) conducted a health hazard evaluation (HHE) at Special Metals Corporation, Princeton Powder Division, Princeton, Kentucky. NIOSH conducted this HHE at the request of employees at that facility who were concerned about the possible formation of hexavalent chromium (Cr[VI]) in the specialty alloy production operations, and of the potential health hazards from exposures to this and other materials associated with those operations. Hea... (Click to show more) The National Institute for Occupational Safety and Health (NIOSH) conducted a health hazard evaluation (HHE) at Special Metals Corporation, Princeton Powder Division, Princeton, Kentucky. NIOSH conducted this HHE at the request of employees at that facility who were concerned about the possible formation of hexavalent chromium (Cr[VI]) in the specialty alloy production operations, and of the potential health hazards from exposures to this and other materials associated with those operations. Health effects mentioned in the request included nose bleeds, sinusitis, gastric disturbance, and fatigue. In response to this request, NIOSH investigators conducted an initial environmental and medical investigation at the site on July 23 and 24, 1997. NIOSH investigators collected 5 personal breathing-zone (PBZ) and 4 area air samples for Cr(VI), 7 PBZ and 4 area air samples for heavy metals, and 6 residual process bulk-material samples for Cr(VI). Two areas of the facility were also evaluated for noise levels. Based upon the initial findings, the NIOSH investigators determined that a follow-up visit was necessary to better characterize workers' exposures to several of the metals used at the facility, by conducting biological monitoring and additional environmental monitoring. The follow-up visit was conducted on September 17-18, 1998. During this visit, NIOSH investigators collected a total of 40 PBZ and 8 area air samples for Cr(VI), 38 PBZ and 7 area air samples for heavy metals, 4 bulk-material samples for Cr(VI), 2 PBZ air samples for respirable crystalline silica, 1 area "bulk-air" sample for crystalline silica, and 2 bulk-material samples for crystalline silica. In general, the highest PBZ air sample concentrations of nickel, cobalt, total chromium, and niobium were found in the furnace bay, laboratory, and inert screening areas. During the initial survey, 1 air sample (collected in the breathing zone of the laboratory assistant) exceeded the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) for nickel (1000 micrograms per cubic meter [µg/m 3 ]) and cobalt (100 µg/m 3 ). Five PBZ air samples exceeded the NIOSH Recommended Exposure Limit (REL) for nickel (15 µg/m 3 ) and 1 PBZ air sample exceeded the REL for cobalt (50 µg/m 3 ). Two PBZ air samples exceeded the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLV) for cobalt (20 µg/m 3 ). One PBZ air sample exceeded the NIOSH REL and the ACGIH TLV for total chromium (500 µg/m 3 ). Bulk sample analysis revealed that Cr(VI) is present in the facility, however all PBZ air sample concentrations for Cr(VI) were below relevant evaluation criteria. During the follow-up survey, 2 air samples (collected in the breathing zone of the laboratory assistant and furnace operator's helper) exceeded the OSHA PEL for nickel and cobalt. Twenty-two PBZ air samples exceeded the NIOSH REL for nickel and four PBZ air samples exceeded the REL for cobalt. Seven PBZ air samples exceeded the ACGIH TLV for cobalt. All results for total chromium were below relevant evaluation criteria. Bulk sample analysis confirmed the initial survey results that Cr(VI) is present in the facility. However, all Cr(VI) PBZ air samples collected were below relevant evaluation criteria. All samples collected for crystalline silica resulted in nondetectable concentrations. Sample results in many cases represent potential exposures, rather than actual inhalation exposures, due to employees wearing respirators. During the follow-up evaluation, all chromium and cobalt levels in urine were well below their respective biological exposure indices. There is no biological exposure index for nickel in the United States. Urine nickel levels, however, suggested that all 48 participating employees may have been exposed to nickel at work. We found a potential health hazard from exposure to nickel and cobalt at this facility. Air samples showed potential employee exposures to nickel and cobalt exceeding relevant evaluation criteria. Bulk and air samples indicated the presence of Cr(VI) in various production areas of the facility, however all personal breathing zone air samples collected for Cr(VI) were below relevant evaluation criteria. Urine samples showed evidence of workplace exposure to nickel in all employees, and suggested that low levels of workplace exposure to chromium may be occurring in a small number of workers, but offered no convincing evidence of workplace exposure to cobalt. Use of respirators (by many of the potentially highest-exposed workers) reduced actual inhalation exposures, as well as absorbed doses. Suggestions to improve the health and safety of employees in this facility, through the use of administrative controls, personal protective equipment (PPE) and particularly through the use of engineering control measures to reduce or eliminate reliance on PPE, are presented in the Recommendations section of this report. (Click to show less)
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(2001) University of California, Berkeley, Berkeley, California. (Click to open report)
At the request of the University of California, Berkeley, the National Institute for Occupational Safety and Health (NIOSH) conducted a study of lead-based paint (LBP) exposures during exterior renovation work on campus buildings. Workers' personal airborne lead (PbA) exposures were assessed for eight renovation tasks during a three-day demonstration project. Additionally we measured concomitant area PbA concentrations 6 feet (ft) from the work surfaces, lead in settled dust (PbS) at three dis... (Click to show more) At the request of the University of California, Berkeley, the National Institute for Occupational Safety and Health (NIOSH) conducted a study of lead-based paint (LBP) exposures during exterior renovation work on campus buildings. Workers' personal airborne lead (PbA) exposures were assessed for eight renovation tasks during a three-day demonstration project. Additionally we measured concomitant area PbA concentrations 6 feet (ft) from the work surfaces, lead in settled dust (PbS) at three distances (6, 10, and 20 ft) from work surfaces for five tasks, and determined if these measures were correlated with the workers' PbA exposures. Five workers performed assigned renovation tasks during limited work periods (average time 28 minutes [min]) on 22 painted exterior surface areas (wood windows, wood doors, and metal stairs). A total of 132 work periods were sampled; the work took from 2 to 12 work periods per designated work surface, depending on the area. Lead concentrations in paint chip samples (one per work surface) ranged from 0.23% to 34% lead (Pb) by weight (average 11.3%). Personal PbA exposures were highly variable; range, none detected to 660 micrograms per cubic meter ( g/m3), geometric mean (GM) = 22 g/m3, geometric standard deviation (GSD) 4.3. Personal PbA exposures were significantly associated with task, worker, and paint lead concentration (p <0.001). High-exposure tasks were dry manual sanding (GM = 49 g/m3), dry manual scraping (53 g/m3), power finish sanding (44 g/m3), and power finish sanding with bag (68 g/m3). Low-exposure tasks were power sanding with high-efficiency particulate air (HEPA) exhaust (GM = 6.9 g/m3), wet manual sanding (6.2 g/m3), wet manual scraping (16 g/m3), and flame burning (23 g/m3). The area PbA concentrations at 6 ft distance, which were also highly associated with task, were roughly an order of magnitude below the personal exposures, ranging from none detected to 37 g/m3, GM = 1.5 g/m3, GSD = 3.3. GMs for PbS samples were 3.2 milligrams per square meter (mg/m2) at 6 ft (n=69), 1.4 mg/m2 at 10 ft (n=67), and 0.66 mg/m2 at 20 ft (n=39). Overall PbS levels decreased significantly as distance increased (p <0.0001). At each distance PbS levels were significantly associated with task (p-values 0.024, 0.0015, and <0.0001, respectively). Flame burning was among the tasks associated with the highest area PbA and PbS levels, although personal exposures were relatively low. Surface paint lead concentrations were poorly correlated with the PbA exposures (R = 0.30). Personal and area PbA levels were significantly correlated (R = 0.49, p <0.0001). Both area and personal PbA concentrations were significantly correlated with PbS levels measured 6 ft and 10 ft from the work surfaces (R values 0.34 to 0.73). Area PbA levels were significantly correlated with the PbS levels at 20 ft as well (R = 0.67). Worker lead exposures for eight renovation tasks on building exteriors with LBP were highly variable. Based on workers' exposures, the eight renovation tasks evaluated fell into two exposure groups. Estimated average exposures during dry manual sanding, dry manual scraping, power finish sanding, and power finish sanding with bag would exceed the permissible exposure limit (PEL) within an 8-hr period. Estimated average exposures for power sanding with HEPA exhaust, flame burning, wet manual sanding, and wet scraping would be below the PEL. Although it resulted in relatively low worker exposures, flame burning was among the tasks associated with the higher lead levels in air and settled dust levels in nearby areas. The power finish sander with a cloth dust bag was not effective in controlling worker exposures; the random-orbital power sanding equipped with HEPA-filtered exhaust ventilation appeared to be highly effective. Recommendations are provided in this report to help prevent hazardous worker exposures to LBP during renovation of surfaces with LBP. (Click to show less)
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(2001) Wire Rope Corporation of America, Sedalia, Missouri. (Click to open report)
In March 2000, the National Institute for Occupational Safety and Health (NIOSH) received a confidential request from a group of employees to conduct a health hazard evaluation (HHE) at the Wire Rope Corporation of America (WRCA) in Sedalia, Missouri. The HHE request stated that some employees experienced symptoms of nose bleeds, eye irritation, and unspecified respiratory symptoms that were believed to be related to exposures to metal dust and asphalt fume at work. Employees were also concerned... (Click to show more) In March 2000, the National Institute for Occupational Safety and Health (NIOSH) received a confidential request from a group of employees to conduct a health hazard evaluation (HHE) at the Wire Rope Corporation of America (WRCA) in Sedalia, Missouri. The HHE request stated that some employees experienced symptoms of nose bleeds, eye irritation, and unspecified respiratory symptoms that were believed to be related to exposures to metal dust and asphalt fume at work. Employees were also concerned about hazardous noise levels, poor lighting, and lack of exhaust ventilation to control air contaminants. A site visit on June 14-16, 2000, included a walk-through inspection of the facility's processes and medical interviews. On June 28-29, 2001, personal breathing-zone (PBZ) and area air samples were collected for metal dust and asphalt fume. To measure asphalt fume, air samples were collected and analyzed for the total particulate, the benzene-soluble particulate fraction, and polycyclic aromatic compounds (PACs). Noise exposures and lighting levels were also measured. Six full-shift PBZ air samples showed exposures to metal dust that were less than 1 percent of the most stringent occupational exposure limit available. Six short-term air samples collected for asphalt fume (measured as total particulate) showed that utility workers' exposures ranged up to 3.2 milligrams per cubic meter (mg/m3), below the NIOSH 15-minute ceiling limit of 5 mg/m3. Air sampling for the benzene-soluble particulate fraction of asphalt showed a strander operator's time-weighed average (TWA) exposure as high as 0.8 mg/m3, a concentration which exceeded the American Conference of Governmental Industrial Hygienists' (ACGIH) time-adjusted Threshold Limit Value (TLV) of 0.25 mg/m3 for a 12-hour TWA concentration. Two utility workers' exposures of 0.3 mg/m3 and 0.4 mg/m3 also exceeded the 12-hour adjusted ACGIH TLV for benzene-soluble particulate. Although no occupational exposure limits are currently available for PACs as a group, area air sampling showed the most abundant subclass of PACs were those believed to be associated with irritative effects. A total of 15 workers were interviewed, including all three of the utility workers present during our site visit. The workers had complaints of headache, upper respiratory irritation, increases of allergy symptoms, cough, and dry eyes. The symptoms generally improve when the employees leave the work site. Interviewed employees noted that the majority of symptoms and complaints have decreased in frequency and severity following elimination of the scrap cutting and some descaling processes. Workers reported that current symptoms are frequently related to exposure to asphalt fume from the large lube holding tanks. The vast majority of workers at the WRCA are exposed to excessive noise levels; some up to 9 ½ times the allowable dose for a 12-hour work shift. All employees surveyed have noise exposures that require them to be included in a hearing conservation program. Illumination levels range from 8 to 76 foot-candles, which are generally less than the American National Standard Institute (ANSI) recommended range of 50 to 100 foot-candles for machining processes at WRCA. Workers who handle liquid asphalt are overexposed to asphalt fume (measured as benzene-soluble particulate). The majority of WRCA workers are exposed to excessive noise levels, and most areas of the plant are poorly illuminated. Interviewed workers complained of headache, upper respiratory irritation, increases of allergy symptoms, cough, and dry eyes. However, these employees have noticed a decrease in the frequency and severity of these symptoms and complaints since scrap cutting and some descaling processes have stopped. Workers also reported that current symptoms are frequently related to exposure to asphalt fume from the large lube holding tanks. Recommendations are offered to reduce exposures to asphalt fume and hazardous noise levels, and to improve lighting at work stations. (Click to show less)
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