The following HTML text is provided to enhance online
readability. Many aspects of typography translate only awkwardly to HTML.
Please use the page image
as the authoritative form to ensure accuracy.
Gulf War and Health: Insecticides and Solvents, Volume 2
Summary and Conclusion
The relationship between exposure to organic solvents and bone cancer was reported in only four cohort studies, representing three different solvent exposures. Each study had low power, and exposure assessment relied primarily on job titles as surrogates of exposure. No case-control studies of bone cancer were identified. Studies with larger numbers of exposed cases (increased power) and more precise exposure assessment are needed for the committee to evaluate the relationship between solvent exposures and risk of bone cancer. Table 6.16 identifies the key studies and relevant data points reviewed by the committee in drawing its conclusion. Unless indicated in the table, the study populations include both men and women.
The committee concludes, from its assessment of the epidemiologic literature, that there is inadequate/insufficient evidence to determine whether an association exists between chronic exposure to solvents under review and bone cancer.
TABLE 6.16 Selected Epidemiologic Studies—Bone Cancer and Exposure to Organic Solvents
Reference
Study Population
Exposed Cases
Estimated Relative Risk (95% CI)
Trichloroethylene
Cohort Study—Mortality
Blair et al., 1998
Aircraft maintenance workers in Utah, employed in exposed area >1 year
5
2.1 (0.2–18.8)
Benzene
Cohort Study—Mortality
Wong, 1987a,b
Male Chemical Manufacturers Association workers
Continuous exposure
2
3.17 (0.38–11.46)
Duration of exposure
<5 years
1
2.63
5–14 years
1
6.63
≥15 years
0
—
Unspecified Mixtures of Organic Solvents
Cohort Study—Incidence
Nielsen et al., 1996
Danish lithographers, ever employed
1
11.4 (0.6–56.0)
Cohort Study—Mortality
Fu et al., 1996
Shoe-manufacturing workers
English cohort, employed in 1939
6
2.08 (0.76–4.52)
Probable solvent based on work area
1
1.12 (0.03–6.26)
Florence cohort, ever employed
0
0 (0.0–3.45)
SOFT TISSUE SARCOMA
Because of the lack of available studies on the relationship between exposure to organic solvents and soft tissue sarcomas (STS), a conclusion regarding association could not be drawn. Only one study (Serraino et al., 1992) identified by the committee analyzed the relationship between relevant exposures reviewed in this report (“benzene/solvents” and “dyes/paints”) and STS. Although the population-based case-control study observed an increased risk of STS among men exposed to “benzene/solvents” for more than 10 years (OR=2.2, 95% CI=0.9–5.5), the study was limited by the use of self-reported exposures. Additional studies are needed to support the relationship before a conclusion regarding association can be drawn.