Personal PM2.5 exposure among wildland firefighters working at prescribed forest burns in southeastern United States.
This study investigated occupational exposure to wood and vegetative smoke in a group of 28 forest firefighters at prescribed forest burns in a southeastern U.S. forest during the winters of 2003-2005. During burn activities, 203 individual person-day PM{sub 2.5} and 149 individual person-day CO samples were collected; during non-burn activities, 37 person-day PM{sub 2.5} samples were collected as controls. Time-activity diaries and post-work shift questionnaires were administered to identify factors influencing smoke exposure and to determine how accurately the firefighters qualitative assessment estimated their personal level of smoke exposure with discrete responses: 'none' or 'very little,' 'low,' 'moderate,' 'high,' and 'very high.' An average of 6.7 firefighters were monitored per burn, with samples collected on 30 burn days and 7 non-burn days. Size of burn plots ranged from 1-2745 acres (avg = 687.8). Duration of work shift ranged from 6.8-19.4 hr (avg = 10.3 hr) on burn days. Concentration of PM{sub 2.5} ranged from 5.9-2673 {mu}g/m{sup 3} on burn days. Geometric mean PM{sub 2.5} exposure was 280 {mu}g/m{sup 3} (95% CL = 140, 557 {mu}g/m{sup 3}, n = 177) for burn day samples, and 16 {mu}g/m{sup 3} (95% CL = 10, 26 {mu}g/m{sup 3}, n = 35) on non-burn days. Average measured PM{sub 2.5} differed across levels of the firefighters categorical self-assessments of exposure (p < 0.0001): none to very little = 120 {mu}g/m{sup 3} (95% CL = 71, 203 {mu}g/m{sup 3}) and high to very high = 664 {mu}g/m{sup 3} (95% CL = 373, 1185 {mu}g/m{sup 3}); p < 0.0001 on burn days. Time-weighted average PM{sub 2.5} and personal CO averaged over the run times of PM{sub 2.5} pumps were correlated (correlation coefficient estimate, r = 0.79; CLs: 0.72, 0.85). Overall occupational exposures to particulate matter were low, but results indicate that exposure could exceed the ACGIH{reg_sign}-recommended threshold limit value of 3 mg/m{sup 3} for respirable particulate matter in a few extreme situations. Self-assessed exposure levels agreed with measured concentrations of PM{sub 2.5}. Correlation analysis shows that either PM{sub 2.5} or CO could be used as a surrogate measure of exposure to woodsmoke at prescribed burns.
- Research Organization:
- USDA Forest Service-Savannah River, New Ellenton, SC
- Sponsoring Organization:
- USDOE; USDOE EM Office of Program and Site Support (EM-50)
- DOE Contract Number:
- AI09-00SR22188
- OSTI ID:
- 1027224
- Report Number(s):
- 11-07-P; na; TRN: US201121%%415
- Journal Information:
- Journal of Occupational and Environmental Hygiene, Vol. 8, Issue 8; ISSN 1545-9624
- Country of Publication:
- United States
- Language:
- English
Similar Records
Biological monitoring of smoke exposure among wildland firefighters: Apilot study comparing urinary methoxyphenols with personal exposures to carbon monoxide, particulate matter, and levoglucosan.
Biological monitoring of smoke exposure among wildland firefighters: Apilot study comparing urinary methoxyphenols with personal exposures to carbon monoxide, particulate matter, and levoglucosan.