A meta-analysis of occupational trichloroethylene exposure and multiple myeloma or leukaemia

Abstract

Background Trichloroethylene (TCE) has been widely used as an industrial solvent and degreasing agent. AimsWe conducted a meta-analysis of epidemiologic studies of occupational TCE exposure and multiple myeloma (MM) or leukaemia. MethodsWe identified a total of eight cohort or case-control studies that enumerated a TCE-exposed study population and presented relative risk (RR) estimates for MM (n 5 7) and/or leukaemia (n 5 7). The individual studies included aerospace or aircraft workers (n 5 3 studies), workers from a transformer manufacturing plant (n 5 1 study) and workers from numerous occupations who, based on biomonitoring or extensive industrial hygiene exposure measurements, were likely exposed to TCE (n 5 4). We used random effects models to calculate summary relative risk estimates (SRRE).In addition, we examined heterogeneity across studies and the relative influence of each individual study on the overall meta-analysis. ResultsNo association was observed for MM (SRRE 5 1.05, 95% CI: 0.80-1.38; P value for heterogeneity 5 0.94) or leukaemia (SRRE 5 1.11, 95% CI: 0.93-1.32; P value for heterogeneity 5 0.50), based on TCE-exposed subgroup meta-analyses. Study-specific RR estimates for MM ranged between 0.57 and 1.62. RRs for leukaemia ranged between 1.05 and 1.15 in five studies, while one study reported a 2-fold increased RR and another study reported an inverse association of 0.60. All confidence intervals (CIs) for study-specific estimates included 1.0. ConclusionsThe results of this meta-analysis do not support an etiologic association between occupational TCE exposure and risk of MM or leukaemia.

Occupational exposure to organic solvents and lymphoid neoplasms in men: results of a French case-control study

“…The absence of any association between chlorinated solvents and MM (OR=1.1 (0.5 to 2.2)) is also consistent with a recent meta-analysis16 (meta-RR=1.1 (0.8 to 1.4)).…”

Retrospective cohort study of a microelectronics and business machine facility

“…These findings are consistent with the literature. A meta-analysis of seven studies assessing the relation between TCE and leukemia reported very modest (RR 1.05–1.15), non-significant increases in risk in five of them [Alexander et al, 2006], and an Institute of Medicine (IOM) report [2003] concluded that there was insufficient evidence to determine whether TCE and/or PCE exposures are associated with leukemia risk [IOM, 2003]. An association between PCE and acute CNS effects is well established; literature on associations with chronic nervous system disease is sparse, with inconsistent results [National Research Council (NRC), 2009; Goldman et al, 2012].…”

Risk Factors for Multiple Myeloma: A Systematic Review of Meta-Analyses

“…[27][28][29][30][31][32][33][34] Among the remaining 29 articles, 7 were presented only as a supplement, as they were updated by more recent publications. With regard to updates, the meta-analysis by Alexander et al 57 61 The Supplemental Table 1 in the online version presents the characteristics of these meta-analysis that have been updated by more recent ones.…”