Journal of the Air & Waste Management Association
ISSN: 1047-3289 (Print) (Online) Journal homepage: http://www.tandfonline.com/loi/uawm18
Measurement of Personal Carbon Monoxide Exposures by Mailed Passive Sampler Kiyoung Lee , Yukio Yanagisawa , John D. Spengler & Irwin H. Billick To cite this article: Kiyoung Lee , Yukio Yanagisawa , John D. Spengler & Irwin H. Billick (1992) Measurement of Personal Carbon Monoxide Exposures by Mailed Passive Sampler, Journal of the Air & Waste Management Association, 42:9, 1212-1213, DOI: 10.1080/10473289.1992.10467070 To link to this article: http://dx.doi.org/10.1080/10473289.1992.10467070
Published online: 06 Mar 2012.
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Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=uawm18 Download by: [91.230.110.27]
Date: 04 June 2016, At: 13:47
NOTE-BOOK Measurement of Personal Carbon Monoxide Exposures by Mailed Passive Sampler
Downloaded by [91.230.110.27] at 13:47 04 June 2016
Kiyoung Lee, Yukio Yanagisawa, John D. Spengler Harvard School of Public Health Boston, Massachusetts
Reliable knowledge of individual or population exposure to air pollutants is an important element in an epidemiological study of air pollution. Within the concept of total human exposure, personal exposures to air pollutants depend on people's activity patterns. 1 Use of a passive sampler is receiving attention as a means to measure actual personal exposure to hazardous air pollutants, since personal exposure can be measured by the sampler without disturbing daily human activities. A passive sampler for carbon monoxide (CO) was developed to measure low-level, time-weighted average (TWA) CO concentrations using a modified zeolite.2 Carbon monoxide transferred through a small diffusion tube was adsorbed to the Y-type zeolite of which the sodium ion was partially exchanged with the Zn ion. A fused silica capillary column was used for the diffusion tube. After the thermal desorption, the collected CO was converted to methane for analysis by gas chromatography (GC) with a flame ionization detector (FID). The accuracy, precision and effects of environmental factors during the use of passive samplers have been tested in laboratory set-ups and are described elsewhere.2 The sampler can measure CO exposures of 30 to 1600 ppm • h with 8 percent precision. Effects of environmental factors such as humidity, temperature and wind velocity were negligible in the detection of CO exposures by the sampler. The objective of this study was to determine the effectiveness of written instructions on the use of the passive sampler. Effects of local mailing on the CO sampler performance were also investigated. Experimental Methods
Passive samplers for carbon monoxide were provided as described in the previous study.2'3 The passive sampler was stored in a storage tube. 2 To undertake the CO measurement, the sampler was taken out of the storage tube and exposed to air for 24 hours. After sampling, the passive sampler was placed into the storage tube and sealed by a separate cap in which oil clay was placed. The collected CO was thermally desorbed from the adsorbent, separated from other gases by gas chromatography, and converted to methane prior to analysis with a flame ionization detector. The sampling rate of the passive sampler was 2.8 ml/day, according to the laboratory experiments.2 Personal exposures of 22 subjects to CO were measured for 24 hours by the CO passive sampler in May 1991. The 22 participants were students of the Harvard Extension School Copyright 1992—Air & Waste Management Association
1212
Irwin H. Billick Gas Research Institute Chicago, Illinois
who were noncompulsorily recruited in a class. The participants did not previously know about how to use a CO passive sampler. Six passive samplers, placed inside a polystyrene foam box, were mailed to each subject along with a one-page instruction sheet describing how to use the sampler (see Appendix), a time activity log, and a questionnaire asking characteristics of each subject. The survey protocol indicated sampling locations, duration, duplicate samplers, and a blank sampler. Four passive samplers were used to measure personal exposure to CO concentrations in the bedroom, kitchen and office. One sampler was a duplicate and one was used as a field blank. The locations of the duplicates were randomly designated among the four sampling locations for each person. Locations where the subject spent time were recorded, along with exposure time, on the time activity log sheet by the participants (Figure 1). Locations were classified in four categories: home, work, commute and other. Except for the blank, the samplers were exposed for 24 hours at the designated locations. Results and Discussion
The 24-hour TWA CO concentrations at the designated locations were somewhat log-normally distributed. The geometric mean of the personal exposures was 1.2 ppm. The geometric mean of CO concentration in the kitchen (1.1 ppm) was slightly higher than that in the bedroom (0.9 ppm). The arithmetic mean of CO concentration in the office (1.3 ppm) was the highest among the CO concentrations at the four sampling locations. If a passive sampler can be mailed, it is useful as a field survey instrument to assess air pollution levels. The advantages of mailing the passive sampler are speed and lower cost. However, the sampler must also be safely delivered. Six samplers were placed in a polystyrene box and sent and returned by mail without any major problems. Carbon monoxide concentrations in potentially hazardous environHOME WORK bedroom other in out of room office office 6:00 AM 6:30 7:00 7:30 8:00 8:30 9:00 9:30 10:00 10:30 11:00 11:30 12:00 PM 12:30
j i
COMMUTl 1
OTHER 2
3
! .
| !
Figure 1. Time activity log.
J. Air Waste Manage. Assoc.
1.3 cm
Rubber septum
Acknowledgment
0.6 cm
0.6 cm Plastic cop Fishing line
The authors are grateful to the 22 students of the Harvard Extension School who participated and sincerely followed our instructions. We also thank Louise McCorkle for editing the manuscript. This research project was partially supported by the Gas Research Institute (Contract #5082-251-0739) and Pacific Gas and Electric.
Figure 2. The CO passive sampler without the storage tube.
Downloaded by [91.230.110.27] at 13:47 04 June 2016
References
ments can be quickly and inexpensively monitored by use of mailed passive samplers. The low unit cost of the passive sampler provides massive measurements essential for epidemiological study within a limited budget. The passive sampler is easily operated by subjects with a minimum of training. The one-page instruction about how to open and close the sampler was effective. Use of the passive sampler was not explained in person to the participants, but they successfully used the sample based on the written instruction provided. However, the use of the separate cap to stop the exposure appeared to be a possibly confusing step. One subject did not use the separate cap in which oil clay was placed. The need for the separate cap can be omitted by the elimination of the storage tube. The storage tube will be eliminated by the new configuration (Figure 2). A two-page questionnaire characterizing the subject's house and office, such as the heating system, parking facilities, commuting time, and smoking environments was answered by each participant. The small sample size was not enough to carry out detailed statistical analyses. Since the characteristics of the subjects were not controlled when selecting subjects, the statistical association of the CO exposures and these factors could not be detected from the small number of subjects. The relationship between differences in the duplicate passive samplers and average CO concentrations of the duplicates is shown in Figure 3. The difference of the duplicate was slightly increased with the increase of CO concentration. The average differences of all the duplicates, including the two outliers of 2.5 ppm, were 0.61 ppm in a range of 0.02 to 2.5 ppm in the field study. Most of the difference can be explained by the variation of blank samplers. The blank passive sampler can be contaminated by a small amount of CO during the assembly process. Contaminations cause variation in the measurements of the blank and exposed samplers. Even though the passive samplers were exposed in various environmental conditions, the difference of the duplicate passive samplers (0.61 ppm) indicated relatively close to the standard deviation (0.4 ppm) of the blank sampler.
3 4 5 6 7 Average of duplicates (ppm)
9
10
Figure 3. Relationship between difference of duplicate passive samplers and average CO measurement of the duplicate sampler in 24 hours exposure.
September 1992
Volume 42, No. 9
1. Ott, W. "Concepts of human exposure to air pollution," Environ. Intnl. 7:179 (1982). 2. Lee, K.; Yanagisawa, Y.; Hishinuma, M.; Spengler, J. D.; Billick, I. H. "Passive sampler for measurement of carbon monoxide using a solid adsorbent," Environ. Sci. Technol. 26: 697 (1992). 3. Hishinuma, M.; Yanagisawa, Y. "Passive Sampler for Carbon Monoxide Using a Solid Adsorbent," Presented at the 82nd Annual Meeting of the Air Pollution Control Association, Anaheim, California, Paper No. 89-82.4 (1989). Appendix
Instruction for use of carbon monoxide passive sampler (COPS) 0. Content a) Six COPS stored in a sealed storage tube Do not open the storage tube until you are ready to start. The opening of the storage tube will cause significant error. b) Six red plastic caps with oil clay 1. To Begin Exposure —remove red plastic cap from storage tube; take out COPS —hold COPS in one hand and use other to pull clear plastic line from COPS —throw the clear plastic liner away —record the time that the COPS was unsealed on the field log (i.e., start time) 2. Placement —(for personal) place COPS in the holder with the end of the brown glass tube facing the open end upward and attach the holder to your clothes —(for stationary) place COPS horizontally, taking care that the top of the COPS is not covered and does not get wet 3. To End Exposure —find the red plastic cap with oil clay —place the exposed COPS (e.g., the end of the brown glass tube facing upward) into the plastic storage tube and seal the storage tube tightly by pressing the red cap with oil clay firmly —place storage tubes into their original polystyrene foam container and record the stop time —mail immediately to HSPH laboratories for analysis *BlankCOPS —place in the polystyrene foam during the measurement Do not open the red plastic cap of blank COPS —When you stop the measurement, open the red cap and seal by red plastic cap with oil clay which is in the box.
K. Lee is a doctoral candidate, Y. Yanagisawa is an associate professor and J. D. Spengler is a professor in the Department of Environmental Health, Harvard School of Public Health, 665 Huntington Ave. Boston, MA 02115. I. H. Billick is manager of Indoor Air Quality & Safety, Gas Research Institute, 8600 West Bryn Mawr Avenue, Chicago, II60631. This work was done at the Harvard School of Public Health. This note manuscript was peer reviewed.
1213
ISSN: 1047-3289 (Print) (Online) Journal homepage: http://www.tandfonline.com/loi/uawm18
Measurement of Personal Carbon Monoxide Exposures by Mailed Passive Sampler Kiyoung Lee , Yukio Yanagisawa , John D. Spengler & Irwin H. Billick To cite this article: Kiyoung Lee , Yukio Yanagisawa , John D. Spengler & Irwin H. Billick (1992) Measurement of Personal Carbon Monoxide Exposures by Mailed Passive Sampler, Journal of the Air & Waste Management Association, 42:9, 1212-1213, DOI: 10.1080/10473289.1992.10467070 To link to this article: http://dx.doi.org/10.1080/10473289.1992.10467070
Published online: 06 Mar 2012.
Submit your article to this journal
Article views: 26
View related articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=uawm18 Download by: [91.230.110.27]
Date: 04 June 2016, At: 13:47
NOTE-BOOK Measurement of Personal Carbon Monoxide Exposures by Mailed Passive Sampler
Downloaded by [91.230.110.27] at 13:47 04 June 2016
Kiyoung Lee, Yukio Yanagisawa, John D. Spengler Harvard School of Public Health Boston, Massachusetts
Reliable knowledge of individual or population exposure to air pollutants is an important element in an epidemiological study of air pollution. Within the concept of total human exposure, personal exposures to air pollutants depend on people's activity patterns. 1 Use of a passive sampler is receiving attention as a means to measure actual personal exposure to hazardous air pollutants, since personal exposure can be measured by the sampler without disturbing daily human activities. A passive sampler for carbon monoxide (CO) was developed to measure low-level, time-weighted average (TWA) CO concentrations using a modified zeolite.2 Carbon monoxide transferred through a small diffusion tube was adsorbed to the Y-type zeolite of which the sodium ion was partially exchanged with the Zn ion. A fused silica capillary column was used for the diffusion tube. After the thermal desorption, the collected CO was converted to methane for analysis by gas chromatography (GC) with a flame ionization detector (FID). The accuracy, precision and effects of environmental factors during the use of passive samplers have been tested in laboratory set-ups and are described elsewhere.2 The sampler can measure CO exposures of 30 to 1600 ppm • h with 8 percent precision. Effects of environmental factors such as humidity, temperature and wind velocity were negligible in the detection of CO exposures by the sampler. The objective of this study was to determine the effectiveness of written instructions on the use of the passive sampler. Effects of local mailing on the CO sampler performance were also investigated. Experimental Methods
Passive samplers for carbon monoxide were provided as described in the previous study.2'3 The passive sampler was stored in a storage tube. 2 To undertake the CO measurement, the sampler was taken out of the storage tube and exposed to air for 24 hours. After sampling, the passive sampler was placed into the storage tube and sealed by a separate cap in which oil clay was placed. The collected CO was thermally desorbed from the adsorbent, separated from other gases by gas chromatography, and converted to methane prior to analysis with a flame ionization detector. The sampling rate of the passive sampler was 2.8 ml/day, according to the laboratory experiments.2 Personal exposures of 22 subjects to CO were measured for 24 hours by the CO passive sampler in May 1991. The 22 participants were students of the Harvard Extension School Copyright 1992—Air & Waste Management Association
1212
Irwin H. Billick Gas Research Institute Chicago, Illinois
who were noncompulsorily recruited in a class. The participants did not previously know about how to use a CO passive sampler. Six passive samplers, placed inside a polystyrene foam box, were mailed to each subject along with a one-page instruction sheet describing how to use the sampler (see Appendix), a time activity log, and a questionnaire asking characteristics of each subject. The survey protocol indicated sampling locations, duration, duplicate samplers, and a blank sampler. Four passive samplers were used to measure personal exposure to CO concentrations in the bedroom, kitchen and office. One sampler was a duplicate and one was used as a field blank. The locations of the duplicates were randomly designated among the four sampling locations for each person. Locations where the subject spent time were recorded, along with exposure time, on the time activity log sheet by the participants (Figure 1). Locations were classified in four categories: home, work, commute and other. Except for the blank, the samplers were exposed for 24 hours at the designated locations. Results and Discussion
The 24-hour TWA CO concentrations at the designated locations were somewhat log-normally distributed. The geometric mean of the personal exposures was 1.2 ppm. The geometric mean of CO concentration in the kitchen (1.1 ppm) was slightly higher than that in the bedroom (0.9 ppm). The arithmetic mean of CO concentration in the office (1.3 ppm) was the highest among the CO concentrations at the four sampling locations. If a passive sampler can be mailed, it is useful as a field survey instrument to assess air pollution levels. The advantages of mailing the passive sampler are speed and lower cost. However, the sampler must also be safely delivered. Six samplers were placed in a polystyrene box and sent and returned by mail without any major problems. Carbon monoxide concentrations in potentially hazardous environHOME WORK bedroom other in out of room office office 6:00 AM 6:30 7:00 7:30 8:00 8:30 9:00 9:30 10:00 10:30 11:00 11:30 12:00 PM 12:30
j i
COMMUTl 1
OTHER 2
3
! .
| !
Figure 1. Time activity log.
J. Air Waste Manage. Assoc.
1.3 cm
Rubber septum
Acknowledgment
0.6 cm
0.6 cm Plastic cop Fishing line
The authors are grateful to the 22 students of the Harvard Extension School who participated and sincerely followed our instructions. We also thank Louise McCorkle for editing the manuscript. This research project was partially supported by the Gas Research Institute (Contract #5082-251-0739) and Pacific Gas and Electric.
Figure 2. The CO passive sampler without the storage tube.
Downloaded by [91.230.110.27] at 13:47 04 June 2016
References
ments can be quickly and inexpensively monitored by use of mailed passive samplers. The low unit cost of the passive sampler provides massive measurements essential for epidemiological study within a limited budget. The passive sampler is easily operated by subjects with a minimum of training. The one-page instruction about how to open and close the sampler was effective. Use of the passive sampler was not explained in person to the participants, but they successfully used the sample based on the written instruction provided. However, the use of the separate cap to stop the exposure appeared to be a possibly confusing step. One subject did not use the separate cap in which oil clay was placed. The need for the separate cap can be omitted by the elimination of the storage tube. The storage tube will be eliminated by the new configuration (Figure 2). A two-page questionnaire characterizing the subject's house and office, such as the heating system, parking facilities, commuting time, and smoking environments was answered by each participant. The small sample size was not enough to carry out detailed statistical analyses. Since the characteristics of the subjects were not controlled when selecting subjects, the statistical association of the CO exposures and these factors could not be detected from the small number of subjects. The relationship between differences in the duplicate passive samplers and average CO concentrations of the duplicates is shown in Figure 3. The difference of the duplicate was slightly increased with the increase of CO concentration. The average differences of all the duplicates, including the two outliers of 2.5 ppm, were 0.61 ppm in a range of 0.02 to 2.5 ppm in the field study. Most of the difference can be explained by the variation of blank samplers. The blank passive sampler can be contaminated by a small amount of CO during the assembly process. Contaminations cause variation in the measurements of the blank and exposed samplers. Even though the passive samplers were exposed in various environmental conditions, the difference of the duplicate passive samplers (0.61 ppm) indicated relatively close to the standard deviation (0.4 ppm) of the blank sampler.
3 4 5 6 7 Average of duplicates (ppm)
9
10
Figure 3. Relationship between difference of duplicate passive samplers and average CO measurement of the duplicate sampler in 24 hours exposure.
September 1992
Volume 42, No. 9
1. Ott, W. "Concepts of human exposure to air pollution," Environ. Intnl. 7:179 (1982). 2. Lee, K.; Yanagisawa, Y.; Hishinuma, M.; Spengler, J. D.; Billick, I. H. "Passive sampler for measurement of carbon monoxide using a solid adsorbent," Environ. Sci. Technol. 26: 697 (1992). 3. Hishinuma, M.; Yanagisawa, Y. "Passive Sampler for Carbon Monoxide Using a Solid Adsorbent," Presented at the 82nd Annual Meeting of the Air Pollution Control Association, Anaheim, California, Paper No. 89-82.4 (1989). Appendix
Instruction for use of carbon monoxide passive sampler (COPS) 0. Content a) Six COPS stored in a sealed storage tube Do not open the storage tube until you are ready to start. The opening of the storage tube will cause significant error. b) Six red plastic caps with oil clay 1. To Begin Exposure —remove red plastic cap from storage tube; take out COPS —hold COPS in one hand and use other to pull clear plastic line from COPS —throw the clear plastic liner away —record the time that the COPS was unsealed on the field log (i.e., start time) 2. Placement —(for personal) place COPS in the holder with the end of the brown glass tube facing the open end upward and attach the holder to your clothes —(for stationary) place COPS horizontally, taking care that the top of the COPS is not covered and does not get wet 3. To End Exposure —find the red plastic cap with oil clay —place the exposed COPS (e.g., the end of the brown glass tube facing upward) into the plastic storage tube and seal the storage tube tightly by pressing the red cap with oil clay firmly —place storage tubes into their original polystyrene foam container and record the stop time —mail immediately to HSPH laboratories for analysis *BlankCOPS —place in the polystyrene foam during the measurement Do not open the red plastic cap of blank COPS —When you stop the measurement, open the red cap and seal by red plastic cap with oil clay which is in the box.
K. Lee is a doctoral candidate, Y. Yanagisawa is an associate professor and J. D. Spengler is a professor in the Department of Environmental Health, Harvard School of Public Health, 665 Huntington Ave. Boston, MA 02115. I. H. Billick is manager of Indoor Air Quality & Safety, Gas Research Institute, 8600 West Bryn Mawr Avenue, Chicago, II60631. This work was done at the Harvard School of Public Health. This note manuscript was peer reviewed.
1213
