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HANDLING IRRADIATED MAIL
Health Hazard Evaluation (HHE) Report: Office of Personnel Management (OPM)
February 1, 2002
United States Office of Personnel Management
1900 East Street N.W.
Washington, D.C. 20415
On January 17, 2002, the National Institute for Occupational Safety and Health (NIOSH) received a request from management officials at the United States Office of Personnel Management (OPM) regarding health concerns related to handling and opening irradiated mail at the OPM office building in Washington, D.C. OPM employees in the building expressed concerns about symptoms such as nose bleeds, eye irritation, skin rashes, and upper/lower respiratory irritation. This letter summarizes the monitoring results obtained during our investigation. We are awaiting laboratory analytical results of samples collected for formaldehyde.
In preparation for this evaluation, we decided to sample for potential contaminants that may be derived from heated mail as a result of irradiation. Contaminants identified from heated mail that may be associated with worker symptoms include small particulate, volatile organic compounds (VOCs) derived from inks and plastics in the mail, and formaldehyde. Other possible contaminates that may be generated as byproducts of the irradiation process include ozone and carbon monoxide. During the evaluation, we also sampled for typical indoor air environmental parameters such as carbon dioxide, temperature, and relative humidity.
On January 22, 2002, an opening conference was held with management officials and union representatives (the American Federation of Governmental Employees [AFGE]) where information was obtained on the building and the areas where the employees had concerns about potential exposures. After the opening conference, samples were collected throughout the building where workers handle, process, and open the mail.
In addition to the environmental assessment of the building, confidential medical interviews were conducted to assess health concerns potentially related to the work environment. A closing conference was held in the OPM building on January 23, 2002, during which preliminary findings and recommendations were discussed.
Discussion and Results
Monitoring inside the building was conducted for small particulate, VOCs, formaldehyde (results will be reported in a separate report), ozone, carbon monoxide (CO), carbon dioxide (CO2), temperature, and relative humidity.
Because small particles can be generated when handling, processing, or opening the mail, and workers in the building reported respiratory irritation which has also been associated with exposure to small particles,, samples were collected throughout the building for particles having an aerodynamic diameter between 0.01 and 0.1 micrometers.
Small particulate measurements inside the building indicated counts between approximately 21,000 particles per cubic centimeter (pa/cc) and 41,000 pa/cc. Outside the building, in the ambient environment, small particulate measurements indicated counts between approximately 62,000 pa/cc and 174,000 pa/cc.
Volatile Organic Compounds (VOCs)
VOCs are a large class of organic chemicals (i.e., containing carbon) that have a sufficiently high vapor pressure to allow some of the compounds to exist in the gaseous state at room temperature. These compounds could result from heating the mail containing inks and plastics. It is important to note, however, that these compounds are typically found in indoor air environments and are emitted in varying concentrations from numerous indoor sources including, but not limited to, carpeting, fabrics, adhesives, solvents, paints, cleaners, waxes, cigarettes, and combustion sources.
Individual VOCs were identified with thermal desorption tubes which were analyzed in the laboratory by a gas chromatograph with a mass selective detector. The results of these tubes indicated various trace amounts (very low concentrations) of VOCs that may be found in indoor air environments. These concentrations are generally in the parts per billion range (ppb) and well below any applicable exposure criteria. Some of the compounds identified on the thermal desorption tubes included various aliphatic hydrocarbons, toluene, benzene, limonene, xylene, butyl cellosolve, isopropanol, ethanol, propanol, ethyl t-butyl ether (MTBE), and fatty acids.
Some of the samples were quantified for benzene, toluene, and limonene. These samples indicated concentrations of benzene less than 0.0004 ppm, toluene concentrations less than 0.002 ppm, and limonene concentrations less than 0.002 ppm. These concentrations are considered extremely low.
Indoor environmental quality studies have measured wide ranges of VOC concentrations in indoor air as well as differences in the mixtures of chemicals which are present. Research suggests that the irritant potency of these VOC mixtures can vary. While in some instances it may be useful to identify some of the individual chemicals which may be present, the concept of total volatile organic compounds (TVOC) has been used in an attempt to predict certain types of health effects. The use of this TVOC indicator, however, has never been standardized.
Some researchers have compared levels of TVOCs with symptoms similar to those of concern among OPM employees (such as headache and irritative symptoms of the eyes, nose, and throat). However, neither NIOSH nor the Occupational Safety and Health Administration currently have specific exposure criteria for VOC mixtures in the nonindustrial environment. Research conducted in Europe suggests that reports of symptoms by building occupants may be more likely to occur when TVOC concentrations increase. It should be emphasized that the highly variable nature of these complex VOC mixtures can greatly affect their irritancy potential. Considering the difficulty in interpreting TVOC measurements, caution should be used in attempting to associate adverse health effects with specific TVOC concentrations.
Total VOC concentrations were collected in the OPM building with a real-time instrument. Prior to taking the instrument to the OPM building, a few measurements were taken in our laboratory in Cincinnati, Ohio. These measurements indicated total VOC concentrations of 3 parts of volatile organic compounds per million parts of air (ppm). Measurements collected in various locations throughout the OPM building where workers processed the mail indicated total VOC concentrations of 1-2 ppm, lower than our "background" levels.
Ozone (O3) may be found as a pollutant around sources of X-rays, and has been associated with symptoms similar to those reported by OPM employees. Therefore, samples were collected to determine whether if any residual ozone may be in the mail. No ozone was detected during our evaluation.
Carbon Monoxide (CO)
CO was also sampled, because of its potential as a byproduct of the irradiation process. CO measurements were collected throughout the building where the mail is processed and handled. CO concentrations were also collected outside in the ambient environment to provide background concentration information. CO measurements indicated higher concentrations outside of the building in the ambient environment than inside the building. Inside the building, CO monitors indicated a peak of 1 ppm, and outside the building CO monitors indicated a peak of 5 ppm. These concentrations are all very low and well below any applicable exposure criteria.
Carbon Dioxide (CO2)
CO2 is a normal constituent of exhaled breath, and if monitored at equilibrium concentrations in a building, may be useful as a screening technique to evaluate whether adequate quantities of fresh air are being introduced into an occupied space. The American National Standards Institute (ANSI)/ASHRAE Standard 62-1989, Ventilation for Acceptable Indoor Air Quality, recommends outdoor air supply rates of 20 cubic feet per minute per person (cfm/person) for office spaces and conference rooms, 15 cfm/person for reception areas, classrooms, libraries, auditoriums, and corridors, and 60 cfm/person for smoking lounges. Maintaining the recommended ASHRAE outdoor air supply rates when the outdoor air is of good quality, and there are no significant indoor emission sources, should provide for acceptable indoor air quality.
CO2 is not considered a building air pollutant, but CO2 concentration is used as an indicator of the adequacy of outside air supplied to occupied areas. Indoor CO2 concentrations are normally higher than the generally constant ambient CO2 concentration. ASHRAE Standard 62-1989 recommends 1,000 ppm as the upper limit for comfort (odor) reasons. When indoor CO2 concentrations exceed 800 ppm in areas where the only known source is exhaled breath, inadequate ventilation is suspected. Elevated CO2 concentrations suggest that other indoor contaminants may also be increased. It is important to note that CO2 is not an effective indicator of ventilation adequacy if the ventilated area is not occupied at its usual level when the measurements are made.
CO2 measurements were collected throughout the building during the afternoon on January 22, 2002. CO2 levels inside the building ranged between 430 ppm to 640 ppm. Measurements collected outside the building indicated concentrations of approximately 400 ppm. CO2 concentrations collected inside the building indicated concentrations below levels where inadequate ventilation may be suspected.
Temperature and Relative Humidity
The American National Standards Institute (ANSI)/ASHRAE Standard 55-1992 specifies conditions in which 80% or more of the occupants would be expected to find the environment thermally acceptable. Assuming slow air movement and 50% RH, the operative temperatures recommended by ASHRAE range from 68-74°F in the winter, and from 73-79°F in the summer. The difference between the two is largely due to seasonal clothing selection. ASHRAE also recommends that RH be maintained between 30 and 60% RH.8 Upper and lower humidity limits are based on the maintenance of acceptable thermal conditions based solely on comfort considerations including thermal sensation, skin wettedness, skin dryness, and eye irritation.8 Some studies have suggested low humidity levels may be associated with symptoms of eye and skin irritation,,,,, similar to symptoms reported among OPM employees.
Temperatures inside the building ranged between 73-75°F. Relative humidity levels inside the building ranged from 18 to 22%.
Medical Interviews with Employees
Confidential interviews were held with the NIOSH medical officer. Thirteen employees were interviewed. Four employees interviewed reported no symptoms, but had questions and concerns about the irradiation process. Three individuals reported a prior history of asthma and reported symptoms of shortness of breath. These individuals were also under treatment for respiratory infections. Other employees had concerns related to dry skin and dermatitis. Concerns raised during the interviews by single employees related to upper respiratory symptoms, burning eyes, nausea, and headaches. One employee reported an episode of hives (this employee was being treated for a respiratory infection at the time).
Workers reported washing their hands more frequently, and using powdered latex gloves while handling mail to protect them from potential contaminants. The use of powdered latex gloves and the increased number of hand washing episodes per employee on a daily basis due to heightened awareness is likely contributing to skin dryness and irritation.
We sampled for contaminants likely to be associated with heated mail as a result of the irradiation process which included small particulate, individual VOCs, TVOCs, ozone, and CO. Results indicated concentrations of individual VOCs, ozone, and CO to be at very low levels, and small particulate and TVOC concentrations were less than "background" levels.
We also sampled for indoor air environmental parameters which included CO2, temperature, and relative humidity. CO2 and temperature measurements were within recommended guidelines. However, relative humidity levels ranged from 18 to 22%, which is below the recommended ASHRAE level of 30 to 60%. Low humidity levels may be associated with symptoms of eye irritation,(9-13) and dry skin which are similar to some of the symptoms reported among OPM employees.
Symptoms reported cannot be distinguished from common symptoms and illnesses which occur more frequently during the winter months (these would include colds, flu, dry irritated mucous membranes, dry eyes, and dry skin) due to low building humidity and spending an increased amount of time indoors.
- In view of these results, certain measures can be employed to help control and reduce symptomatology.
- First it is important to keep a systematic reporting log of symptoms in the employee medical clinic. The log may provide useful information over time.
- Individuals who choose to wear gloves while handling irradiated mail should be provided non-latex, powder-free gloves to decrease the potential for skin irritation.
- Individuals may continue to wash their hands frequently throughout the day especially after removing gloves or following the handling of large amounts of mail, but they should liberally apply hand cream or lotion after each hand washing, as well as frequently throughout the day.
- Individuals who experience eye or nose dryness or irritation may use over-the-counter saline eye drops or saline nose spray as frequently as they feel necessary to alleviate symptoms.
- If the eye or nose symptoms are not improved by these measures, the individual should be evaluated by their health care provider.
- Because low humidity levels have been associated with discomfort and irritation, careful adjustment of humidity levels could be made by someone familiar with the HVAC system.
Thank you for your cooperation with this investigation. A final report will be disseminated when the remaining results are received and analyzed. If you have any questions, please do not hesitate to contact us at (513) 841-4387 or (513) 841- 4463.
Ronald M. Hall, MS
Industrial Hygiene Section
Hazard Evaluations and Technical Assistance Branch
Division of Surveillance, Hazard Evaluations and Field Studies
Jeffery E. Hess, MD
Hazard Evaluations and Technical Assistance Branch
Division of Surveillance, Hazard Evaluations and Field Studies
- Wilson, W.E. and Suh, H.H. Fine Particles and Coarse Particles: Concentration Relationships Relevant to Epidemiological Studies. J. of Air Waste and Managment Assoc. 47:1238-1249.
- Peters, A., Wichmann, H.E., Tuch, T., Heinrich, J., and Heyder, J. Respiratory Effects are Associated with the Number of Ultrafine Particles. Am. Journal of Resp. and Critical Care Medicine. 155:1376-1383.
- Molhave L, Nielsen GD . Interpretation and limitations of the concept "Total Volatile Organic Compounds" (TVOC) as an indicator of human responses to exposures of volatile organic compounds (VOC) in indoor air. Indoor Air, Vol. 2, pp 65-77.
- Molhave L, Bach B, Pedersen OF . Human reactions to low concentrations of volatile organic compounds. Environ Int 12:167-176.
- . Technical Editor Dr. Luigi Parmeggiani. Encyclopedia of Occupational Health and Safety, Third (revised) Edition. International Labour Organization Publications, International Labour Office, CH –1211 Geneva 22, Switzerland.
- ASHRAE . Ventilation for acceptable indoor air quality. Atlanta, GA: American Society for Heating, Refrigeration, and Air-conditioning Engineers. ANSI/ASHRAE Standard 62-1989.
- NIOSH . NIOSH testimony to the U.S. Department of Labor: statement of the National Institute for Occupational Safety and Health. Presented at the public hearing on the proposed rulemaking on Indoor Air Quality, September 28, 1994. NIOSH policy statements. Cincinnati, OH: Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health.
- ASHRAE . Thermal environmental conditions for human occupancy. American National Standards Institute/ASHRAE standard 55-1992. Atlanta, GA: American Society for Heating, Refrigerating, and Air-Conditioning Engineers, Inc.
- NIOSH . Hazard evaluation and technical assistance report: Fischer and Porter Company, Warminster, Pennsylvania Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, NIOSH Report No. HHE-80-072-787.
- NIOSH . Hazard evaluation and technical assistance report: Philadelphia Newspapers, Inc., Philadelphia, Pennsylvania. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, NIOSH Report No. HETA-90-363-2115.
- NIOSH . Hazard evaluation and technical assistance report: Shamokin Elementary, Shamokin, Pennsylvania. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, NIOSH Report No. HETA-90-202-2116.
- NIOSH . Hazard evaluation and technical assistance report: National Institute of Mental Health, Rockville, Maryland. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, NIOSH Report No. HETA-82-023-1136.
- NIOSH . Hazard evaluation and technical assistance report: George Washington University Medical Center, Washington, D.C. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, NIOSH Report No. HETA-84-004-1568.
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