Biomonitoring of Chemical Exposure among New York City Firefighters Responding to the World Trade Center Fire and Collapse
Edelman, Philip, Osterloh, John, Pirkle, James, Caudill, Sam P., Grainger, James, Jones, Robert, Blount, Ben, Calafat, Antonia, Turner, Wayman, Feldman, Debra, Baron, Sherry, Bernard, Bruce, Lushniak, Boris D., Kelly, Kerry, Prezant, David, Environmental Health Perspectives
The collapse of the World Trade Center (WTC) on 11 September 2001 exposed New York City firefighters to smoke and dust of unprecedented magnitude and duration. The chemicals and the concentrations produced from any fire are difficult to predict, but estimates of internal dose exposures can be assessed by the biological monitoring of blood and urine. We analyzed blood and urine specimens obtained from 321 firefighters responding to the WTC fires and collapse for 110 potentially fire-related chemicals. Controls consisted of 47 firefighters not present at the WTC. Sampling occurred 3 weeks after 11 September, while fires were still burning. When reference or background ranges were available, most chemical concentrations were found to be generally low and not outside these ranges. Compared with controls, the exposed firefighters showed significant differences in adjusted geometric means for six of the chemicals and significantly greater detection rates for an additional three. Arrival time was a significant predictor variable for four chemicals. Special Operations Command firefighters (n = 95), compared with other responding WTC firefighters (n = 226), had differences in concentrations or detection rate for 14 of the chemicals. Values for the Special Operations Command firefighters were also significantly different from the control group values for these same chemicals and for two additional chemicals. Generally, the chemical concentrations in the other firefighter group were not different from those of controls. Biomonitoring was used to characterize firefighter exposure at the WTC disaster. Although some of the chemicals analyzed showed statistically significant differences, these differences were generally small. Key words: antimony, biomonitoring, dioxins, disaster, firefighters, metals, PAHs, PCBs, VOCs. Environ Health Perspect 111:1906-1911 (2003). doi:10.1289/ehp.6315 available via http://dx.doi.org/[Online 9 September 2003]
The catastrophic collapse of the World Trade Center (WTC) on 11 September 2001 produced unprecedented fire-related exposures for New York City, New York, firefighters. The initial fires, building collapses, and persistent fires that burned for months, while intense rescue and recovery efforts continued, contributed to exposures from a wide variety of pyrolysis, combustion, and pulverized building materials.
Predicting the chemicals and their concentrations produced from a fire is difficult because the composition depends on the diversity of natural and synthetic fuels, fire temperature and duration, availability of oxygen, compression pressure, atmospheric conditions, and the fire's course relative to surrounding topography. Firefighters and other rescue and recovery personnel may inhale gases or vapors released during a fire or collapse and may inhale and ingest particulates. Hand-to-mouth contamination, contamination inside masks, and dermal absorption also may be important Factors affecting chemical absorption. Although some chemicals are common to most fires (Austin et al. 2001), neither knowledge of the burning materials nor environmental measurements can accurately predict the absorbed dose of combustion products. Recent studies have focused on acutely toxic firefighter exposures and specific aspects of firefighter response (Hartzell 1996); however, there has not been a comprehensive biomonitoring assessment of firefighters after a major incident.
Biomonitoring is the measurement of the internal dose of a chemical or its metabolite in body matrices (e.g., blood or urine) and provides critical information about the amount of a chemical that actually enters the body from any source--for example, air, water, dust, soil, food, and other environmental sources (Sampson et al. 1994). Biomonitoring is ideally used in conjunction with measurements of external exposure, however, because in this case personal sampling of firefighter external exposures was not possible initially and often is impractical. …