Health Hazard Evaluations (HHEs)

(2007) Copperhill smelter worker study. (Click to open report)
The union that represented some workers at the smelter asked NIOSH to study worker health. The union and people in the nearby community wanted to know if health problems were related to working in or living near the smelter. Although this study only included smelter workers, NIOSH thought the results would help answer questions about health in the community. Many people in the community worked at the smelter. Also, smelter operators had data about exposures in the plant. These data would help re... (Click to show more) The union that represented some workers at the smelter asked NIOSH to study worker health. The union and people in the nearby community wanted to know if health problems were related to working in or living near the smelter. Although this study only included smelter workers, NIOSH thought the results would help answer questions about health in the community. Many people in the community worked at the smelter. Also, smelter operators had data about exposures in the plant. These data would help researchers better understand whether smelter-related exposures were linked to health problems. Because a study of the smelter workers had been done in the 1980s, this study was possible. The researchers set the following four goals for the study: 1. Compare death rates and causes of death in smelter workers with those in the general population. 2. Describe the work environment in the smelter by work area, job title, and levels of exposure to six agents. 3. Describe the smoking history of smelter workers and use this information to help understand the cause-of-death results. 4. Examine whether specific causes of death were related to exposures in the smelter work setting. The study included 2,422 men who worked in the smelter, mill, or sulfur plant for 3 or more years between January 1946 and April 1996. For the years 1949 through 2000, the researchers found out whether these workers were living or deceased. If the workers were deceased, the researchers obtained information about their cause of death. The researchers used information from national and state records to learn whether people in the study had died. The researchers then obtained information about the causes of those deaths. They also used information from records in the smelter about the age, race, and sex of people in the study. They compared the number of deaths of smelter workers to the number that would be expected in groups of people who did not work in the smelter. These included the general population of the United States and the population of the counties around the smelter. They made these comparisons for all causes of death combined, for groups of diseases (such as all cancer or all lung disease), and for specific diseases (such as lung cancer or cerebrovascular disease, also known as stroke). They used statistical tests to decide if the results were meaningful. When they saw meaningful differences, they looked to see if death rates were related to exposure. They got exposure information from smelter records and by interviewing workers about smelter operations. To look at exposure, they grouped people by how long they worked in the plant, what department they worked in, their job title, and the level of exposure. They estimated exposure levels for lead, arsenic, cadmium, cobalt, dust, and sulfur dioxide based on records of workplace air sampling done by smelter operators. All causes of death. Of the workers in the study, 961 (41%) were deceased. Researchers found a cause of death for 878 of these. The total number of deaths expected among smelter workers was based on national and local county rates. For all causes of death, all types of cancer, all types of heart disease, respiratory disease other than cancer, and many of the specific causes of death, the rates in the surrounding counties were similar to the national rates. Cancer deaths. Of the workers in the study, 228 died of cancer. This was 18% lower than expected based on national rates and 16% lower based on local county rates. When specific types of cancer were looked at separately, some differences between smelter workers and the general population were found. Most of these differences were based on numbers of deaths so small they were not thought to be important. Eleven workers died of cancer of the central nervous system, an excess of 39% compared to the general population. By statistical tests, this difference was not meaningful. Noncancer deaths. The results did not show that smelter workers had a meaningful increase in the risk of death from any other cause of death. Levels of exposure. The average exposure levels for lead and sulfur dioxide were close to the current workplace limits for these agents. For arsenic, cadmium, cobalt, and dust, the past average exposure levels were much lower than current limits. Causes of death and exposure. After examining all causes of death and all measures of exposure, the researchers looked at two findings more closely. These were the link between arsenic exposure and stroke and the link between cadmium exposure and bronchitis. Stroke and arsenic exposure. Seventy workers died of stroke. The risk of death from stroke was higher for people who worked longer and for people with more arsenic exposure. By statistical tests, this difference was not meaningful. For example, workers with the highest level of total exposure were 1.5 times more likely to die of stroke than unexposed workers, but the p value, a measure of significance, was 0.17; a p value of 0.05 or less is regarded as statistically significant. Bronchitis and cadmium exposure. Seven workers died of bronchitis. The risk of bronchitis death was higher for some exposed workers than for unexposed workers. This finding, however, was not the same for all exposure groups or measures. For example, workers with a moderate level of total cadmium exposure were 14.8 times more likely to die of bronchitis than unexposed workers. But, workers with the highest level of exposure were only 3.8 times more likely to die of bronchitis. The p value for these findings was 0.06, not statistically significant. As with most studies of this type, some factors make it hard for researchers to draw firm conclusions about the findings. First, because complete and accurate information about cigarette smoking was not available, the researchers could not investigate how cigarette smoking affected causes of death. But, it is unlikely that this limitation had an important effect on the conclusions. Second, this study was smaller than studies of other workplaces. The small size makes it less likely that the findings will be statistically significant, even if there is a real risk. Because of this, it is helpful to look at the how the findings of this study fit in with the findings of other studies of smelter workers or of other workers with similar exposures. Death rates for Copperhill smelter workers were lower than expected for all causes of death and from specific cancer and noncancer causes. This is not an unusual finding in studies of workers. So, researchers looked to see if workplace exposures were related to the risk of death from specific causes. One finding of interest was for arsenic and stroke. Another was for cadmium and bronchitis. The researchers concluded it is unlikely that arsenic exposure caused increased stroke risk or that cadmium exposure caused increased bronchitis disease risk in Copperhill workers. This conclusion is based on the detailed analyses of the findings from this study and on evidence from other studies about these exposures and diseases. It is also important to note that other studies of smelter workers have shown that arsenic exposure is related to respiratory cancer. Arsenic exposures in the Copperhill smelter were lower than in other smelters studied. The researchers in this study did not see an increase in respiratory cancer risk. (Click to show less)
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(2007) Interfaith Medical Center, Brooklyn, New York. (Click to open report)
On March 24, 2003, the National Institute for Occupational Safety and Health (NIOSH) received a request from the New York State Nurses Association (NYSNA) to conduct a health hazard evaluation (HHE) at Interfaith Medical Center (IMC) in Brooklyn, New York. The survey was conducted July 30 -August 1, 2003. Air monitoring was conducted in the endoscopy unit for glutaraldehyde and indoor environmental quality (IEQ), and ventilation measurements were taken in the operating room, intensive care unit... (Click to show more) On March 24, 2003, the National Institute for Occupational Safety and Health (NIOSH) received a request from the New York State Nurses Association (NYSNA) to conduct a health hazard evaluation (HHE) at Interfaith Medical Center (IMC) in Brooklyn, New York. The survey was conducted July 30 -August 1, 2003. Air monitoring was conducted in the endoscopy unit for glutaraldehyde and indoor environmental quality (IEQ), and ventilation measurements were taken in the operating room, intensive care unit (ICU), and emergency department at the main facility. IEQ measurements were also taken at the methadone clinic, which is at a separate location. Confidential interviews were conducted with twelve employees in the ICU at the main IMC facility, and an informal interview was conducted with three employees at the methadone clinic. OSHA logs were reviewed as well. Glutaraldehyde levels in air were well below applicable occupational exposure limits. However, approximately half the rooms at the main IMC facility lacked adequate ventilation and there was no mechanical ventilation system in place at the methadone clinic. Some employees were concerned about inadequate ventilation in their workplace. Another mentioned that there was a delay in learning whether a patient had a communicable disease. Employees also expressed satisfaction with management's timely response to their complaints. OSHA logs showed that there were 80 cases of workplace violence over a 2-year period. The NIOSH evaluation identified areas in the main IMC facility with inadequate ventilation. Ventilation at the methadone clinic was nonexistent, leading to complaints of heat exhaustion among employees. NIOSH investigators recommend consultation with ventilation engineers who are familiar with hospital facilities to improve ventilation. NIOSH investigators recommend addressing workplace violence, improving communication between management at the main IMC facility and management at the methadone clinic, as well as between employees and management at the methadone clinic. (Click to show less)
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(2006) Buildings in the Vicinity of the World Trade Center, New York City, New York. (Click to open report)
On January 1, 2002, the National Institute for Occupational Safety and Health (NIOSH) received three health hazard evaluation (HHE) requests from employee representatives at four different work sites: Stuyvesant High School, the Borough of Manhattan Community College (BMCC), 120 Broadway and 40 Rector Street (housing four city agencies), near the World Trade Center (WTC) site. This report summarizes four separate NIOSH investigations, which document the extent of physical and psychological sympt... (Click to show more) On January 1, 2002, the National Institute for Occupational Safety and Health (NIOSH) received three health hazard evaluation (HHE) requests from employee representatives at four different work sites: Stuyvesant High School, the Borough of Manhattan Community College (BMCC), 120 Broadway and 40 Rector Street (housing four city agencies), near the World Trade Center (WTC) site. This report summarizes four separate NIOSH investigations, which document the extent of physical and psychological symptoms among workers at these sites in the months following the September 11, 2001 disaster at the WTC. Each of these reports compared physical and mental health symptoms among employees at these buildings with the same symptoms among employees at comparable New York City work sites distant from the WTC. NIOSH personnel conducted a questionnaire survey of employees at Stuyvesant High School and a comparison high school, La Guardia High School, in late January 2002. The survey occurred at BMCC and a comparison college, York Community College, in mid-March 2002; at 40 Rector Street in early April 2002, and at 120 Broadway (state attorney general's office) in early June 2002. The LeFrak Building, was surveyed in early April 2002 and was the comparison building for 40 Rector Street and 120 Broadway. We used a self-administered questionnaire to ask about physical and mental health symptoms that occurred since September 11 and symptoms still present at the time of the survey. In addition, we used the questionnaire to ask participants about experiences on September 11, about medical diagnoses since then, and about social support. Participation rates were 82%-83% at both high schools and at the 40 Rector Street building, 76% at the comparison office building, about 55%-60% at BMCC, about 45%-50% at the comparison college, and 37% at the 120 Broadway building. In all four studies, the prevalence of physical symptoms, including upper and lower respiratory symptoms, tended to be higher at the work sites near the WTC site than at the comparison work sites. The prevalence of persistent symptoms (upper and lower respiratory symptoms) also tended to be higher. Depressive symptoms and post traumatic stress disorder (PTSD) symptoms were prevalent at Stuyvesant and BMCC, but not at the two office buildings. Likewise, PTSD diagnosed since September 11 was more prevalent at Stuyvesant and BMCC than at their comparison sites, and a similar, though not statistically significant, prevalence ratio was found at the 40 Rector Street building. Newly diagnosed depression was not statistically more prevalent at any of the individual sites than at the comparison sites. All the surveys were limited by the lack of quantitative information about employees' exposures to dust and smoke from the collapsing buildings and fires on September 11 and our inability to infer medical diagnoses solely on the basis of a symptom survey. Since our interim letters were issued, published reports from several studies have described short- and medium-term physical health effects among rescue workers, office workers, and residents from the surrounding community. These studies have provided information suggesting that exposure to the dust cloud and the chemical/physical properties of the dust from the collapse of the buildings on September 11 as well as exposures to combustion products from the burning materials have contributed to the respiratory problems. Continued longitudinal follow-up of those exposed will be necessary to determine whether the changes in spirometry documented up to 5 years post-disaster will lead to chronic problems or whether the initial decline in respiratory function will be followed by recovery, as has been seen in other irritant-exposed groups. Reports of psychological problems have also been well documented since our interim letters were issued. On-going interventions addressing these reactions may help prevent the development of long-lasting psychological sequelae. NIOSH investigators determined that an occupational health hazard due to exposures surrounding the collapse of the World Trade Center existed among the working groups studied. A substantial burden of symptoms of depression and PTSD, as well as physical symptoms of eye irritation and upper airway irritation were present among those surveyed. Recommendations for medical evaluation of symptomatic persons, facilitating access to medical heath services, fostering social support, and training were given. (Click to show less)
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(2006) United States Environmental Protection Agency, Research Triangle Park Durham, North Carolina. (Click to open report)
From September 6 through September 9, 2005, investigators from the National Institute for Occupational Safety and Health (NIOSH), Division of Respiratory Disease Studies, performed a site visit at the Environmental Protection Agency facility at Research Triangle Park in Durham, North Carolina. This evaluation was conducted in response to a request from EPA management for a NIOSH health hazard evaluation regarding a history of particulate exposure and staff health effects in the laboratory areas ... (Click to show more) From September 6 through September 9, 2005, investigators from the National Institute for Occupational Safety and Health (NIOSH), Division of Respiratory Disease Studies, performed a site visit at the Environmental Protection Agency facility at Research Triangle Park in Durham, North Carolina. This evaluation was conducted in response to a request from EPA management for a NIOSH health hazard evaluation regarding a history of particulate exposure and staff health effects in the laboratory areas of the facility. Laboratory staff became aware of excessive indoor particulate levels starting in 2003. Some EPA researchers measured PM2.5 (particulate smaller than 2.5 microns) levels and noted instances where indoor concentrations were higher than outdoor concentrations. Staff in many laboratories started to note a rapid buildup of white dust on surfaces which would quickly recur after cleaning. High efficiency particulate filters in bio-safety cabinets in many laboratories had to be changed out after several months use when normally they would be expected to last several years. Electrical components of several laboratory devices were found to be damaged and to have evidence of corrosion and accumulated particulate. Investigations by EPA/RTP facilities staff revealed that the humidification system in the heating, ventilation, and air conditioning (HVAC) units was causing a buildup of sodium and chloride deposits on the cooling coils and was a potential source of the laboratory particulate. An additional issue contributing to the particulate problem was periodic malfunctioning of ventilation-system controls which would cause transient increased airflows in laboratory areas. Such malfunctions were associated with increased deposition of visible particulate matter on surfaces. These events were referred to as "dumps" by EPA staff. In 2004, a number of laboratory staff in Buildings A and B developed acute health symptoms in laboratories where a dump had just occurred. The symptoms reported by these individuals included cough, shortness of breath, chest pain with inhalation, chest tightness, sore throat, and eye irritation. Some individuals had persistent symptoms for many days prior to eventual resolution, and some had symptoms recur when they tried to return to their usual laboratories. One individual reported receiving a diagnosis of asthma due to the particulate exposure. Despite attempts by EPA/RTP facilities staff to address the particulate problem, employees continued to detect excess particulate in laboratory areas and to experience respiratory symptoms. Results of limited air sampling and observations by NIOSH staff during the site visit suggest that particulate accumulation in the ventilation system air handling units, coupled with periodic loss of control of laboratory airflows by the system, is a likely source of excess particulate in laboratory areas. Other sources of laboratory particulate may include ceiling tiles, floor cleaning activities, and soil and construction activities outside the facility. The ongoing replacement of the cooling coils in the HVAC units, along with utilization of reverse osmosis and a water softener to treat the water for the humidification system, may correct the ventilation system particulate problem. However, the fact that the humidifier atomizer heads will still be relatively close to the cooling coils may cause particulate buildup on the coils to recur. In confidential interviews with 17 employees who requested interviews with NIOSH staff, employees reported health effects they experienced in, or attributed to, the EPA/RTP facility (mostly laboratory areas). The most common reports were of upper and lower respiratory symptoms and eye irritation. These symptoms may represent primarily irritant responses. Whether or not particulate exposures in the laboratories caused or exacerbated asthma in some employees could not be determined from the information available. Particulate accumulation on, and corrosion of, the cooling coils in the HVAC units has likely led to increased amount of visible particulate and PM2.5 in the laboratory areas of the EPA/RTP facility. The particulate may be responsible for the irritant-type symptoms that some employees have experienced while in their laboratories and/or adjacent offices. Symptoms were severe in instances where employees were exposed in relation to a particulate "dump" that resulted from a ventilation-system airflow malfunction. The ongoing replacement of the cooling coils reportedly will take several months to complete. This should decrease the amount of particulate that enters the laboratory areas from the ventilation system and may lead to resolution of employee symptoms. This report contains recommendations for steps that EPA/RTP facilities and health and safety staff should follow to prevent and minimize particulate from the ventilation system and other sources, and to protect employees that may continue to be adversely affected until the particulate problem is eliminated. (Click to show less)
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(2005) Ikens Hardwood Floor Services, Madison, Wisconsin. (Click to open report)
In May 2000, the National Institute for Occupational Safety and Health received a health hazard evaluation (HHE) request from management at Ikens Hardwood Floor Services, Madison, Wisconsin. The request concerned potential lead and wood dust exposures during wood floor refinishing. The floor service company had previously evaluated 41various floor finishes for lead content; among these, 15% exceeded the federal action level for lead-based paint (0.5% lead by weight). NIOSH investigators conducte... (Click to show more) In May 2000, the National Institute for Occupational Safety and Health received a health hazard evaluation (HHE) request from management at Ikens Hardwood Floor Services, Madison, Wisconsin. The request concerned potential lead and wood dust exposures during wood floor refinishing. The floor service company had previously evaluated 41various floor finishes for lead content; among these, 15% exceeded the federal action level for lead-based paint (0.5% lead by weight). NIOSH investigators conducted a site visit in June 2000 at a single-family home in Madison, Wisconsin, where Ikens Hardwood Floor Services was refinishing hardwood floors. General area and personal breathing-zone (PBZ) air samples were collected for lead and wood dust during floor refinishing, and settled dust samples were measured for lead content. Four in situ (in place) surface measurements were taken to measure the lead content in the varnish on floors. Results from the short-term task-based PBZ air samples ranged from 1.5 to 25 micrograms per cubic meter (ug/m3) and were below the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) for lead of 50 ug/m3. However, worker exposures during buffing approached the OSHA Action Limit for lead of 30 ug/m3, assuming that buffing would be performed over an 8-hour work day. Tasks with the greatest potential to produce lead exposures were buffing and final sanding combined with buffing. All of the wood dust exposures measured during rough sanding, rough edging, final sanding/buffing, and buffing tasks exceeded the NIOSH Recommended Exposure Limit (REL) of 1 milligram per cubic meter (mg/m3) for wood dust, if extrapolated to full shift. All of the settled dust collected on the floors of rooms during refinishing, but prior to final finishing, had lead concentrations exceeding U.S. Housing and Urban Development (HUD) federal clearance guidelines for residential floor areas (0.43 milligrams per square meter [mg/m2]). NIOSH investigators conclude that a health hazard exists during buffing and sanding hardwood floors. Workers are exposed to wood dust above the NIOSH REL, and lead exposures approach the OSHA Action Level for lead. Surface dust samples contained levels of lead which exceed federal clearance standards for residential areas. This suggests a potential health hazard to small children in the home during refinishing, and after if the floors are not cleaned. Recommendations for using engineering and administrative controls and wearing respiratory protection during refinishing activities are included in the Recommendations section of this report. (Click to show less)
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