Personal workers' lead exposure during indoor lead-based paint abatement.
Trunov M; Grinshpun SA; Willeke K; Choe KT; Friedman W
Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, 2002 Feb; :1-37
This study addresses personal exposures of lead abatement workers. Personal monitoring of workers' lead exposure was performed during lead-based paint (LBP) abatement of wooden surfaces in a room size environmental chamber. Short-term task-specific lead exposures were determined for dry scraping, dry non-REF A machine sanding, and wet scraping. Lead exposures were also monitored for different work practices during the final cleaning work task immediately after the required I-hour waiting period following active LBP removal. The personal monitoring of workers was performed with the Button Personal lnhalable Aerosol Sampler operated at 4 Lpm and the standard closed- face 37-mm cassette at 2 Lpm. The sampling efficiency curve of the Button Sampler at its flow rate is close to the ACGIH/CEN/ISO inhalable particles sampling efficiency convention, while the more common 37-mm cassette at its commonly-used flow rate is not. The 90% upper confidence levels of short-term worker lead exposures (measured with the Button Sampler) for all of the investigated active LBP removal methods exceeded the half-facepiece air purifying respirator protection level of 500 ug/m3 at least by a factor of 5. The two samplers were compared by correlation analysis which indicated up to 50% higher lead concentrations when measured using the Button Sampler as compared with that measured using the 37-mm cassette. The regression coefficients ranged from 1.08 for final wet cleaning to 1.50 for dry scraping. Microscopic analyses of the samples for all the above-mentioned work tasks showed that the sampler regression coefficients were higher for work tasks with higher percentages of large (> 20 um) inhalable particles. Because large airborne particles may penetrate through a respirator's faceseal leak less readily than submicron particles, the half-facepiece respirator's work protection factor is likely to be sufficient for worker's protection during majority of LBP abatement work tasks. Additional studies on the lead concentration inside face masks should be performed to clarify the situation.
Lead compounds; Exposure levels; Monitoring systems; Air samples; Workplace monitoring
S.A. Grinshpun, Center for Health Related Aerosol Studies, Department of Environmental Health, University of Cincinnati, P.O. Box 670056, Cincinnati, OH 45267-0056
Research Tools and Approaches: Exposure Assessment Methods
National Institute for Occupational Safety and Health
University of Cincinnati, Cincinnati, Ohio