Occupational exposure to solvents and risk of lymphoma subtypes: results from the Epilymph case-control study
7 Sep, 10 | by lelliott
Re: Cocco et al., Occup Environ Med 2010; 67: 341-347 (Original article)
Considering the temporal association between exposure to benzene and the later development of leukaemia it is questionable if this phenomena is also true for NHL (1). From several independent epidemiologic studies with
consistent findings it can be concluded that 10 to 15 years after exposure to benzene has been stopped, the risk of leukaemia is significantly less or even absent (2,3,4).
Assuming that the underlying mechanism for leukaemia and NHL is the same, it would be important to use the large database of the “Epilymph study” to analyze the temporal pattern between exposure and disease.
The study found increased risks for chronic lymphocytic leukaemia after exposure to toluene and xylene. A benzene exposure was excluded. These statistical associations must be discussed with respect to the genotoxicologic evidence of these aromatic hydro-carbons. Compared to benzene, toluene and xylene have not been proven as human carcinogens. The IARC Working Group concluded in 1999, that there is inadequate evidence in humans for the carcinogenicity of toluene and xylenes (5). Therefore the
associations must be interpreted with caution and do not support causality.
1. Triebig G. Implications of latency period between benzene exposure and development of leukemia – a synopsis of literature. Chem Biol Interact 2010; 184: 26-29.
2. Hayes RB, Song-Nian Yin, Dosemeci M. Benzene and the dose related incidence of hematologic neoplasm in China. J Natl Cancer Inst 1997; 89: 1065-1071.
3. Finkelstein MM. Leukemia after exposure to benzene: temporal trends and implications for standards. Am J Ind Med 2000; 38: 1-7.
4. Glass DC, Sim MR, Fritschi L, Gray CN, Jolley DJ, Gibbons CG. Letter to the editor. Leukemia risk and relevant benzene exposure period. Am J Ind Med 2002; 42:481-489.
5. IARC Monographs on the evaluation of carcinogenic risks to humans. Re-evaluation of Some Organic Chemicals, Hydrazine and Hydrogen Peroxide. Volume 71, Part two (Toluene) and Part three (Xylene). World Health Organization International Agency for Research on Cancer, 1999.