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There is little or no evidence to suggest that exposure to formaldehyde causes leukemia, according to a group of researchers.
The team reanalyzed data from a study published in 2010 that suggested a possible link between formaldehyde exposure and myeloid leukemia.
They also reviewed other recent studies investigating the health effects of formaldehyde.
“The weight of scientific evidence does not support a causal association between formaldehyde and leukemia,” said Kenneth A. Mundt, PhD, of Ramboll Environ, a consulting firm focused on environmental, health, and social issues.
Dr Mundt and his colleagues detailed the evidence in the Journal of Critical Reviews in Toxicology.
The team’s research was supported by the Foundation for Chemistry Research and Initiatives (formerly the Research Foundation for Health and Environmental Effects), an organization established by the American Chemistry Council (an industry trade association for American chemical companies).
The study that suggested a possible link between formaldehyde and myeloid leukemia, particularly acute myeloid leukemia (AML), was published in January 2010 in Cancer Epidemiology, Biomarkers & Prevention.
In this study, Luoping Zhang, PhD, of the University of California at Berkeley, and her colleagues compared 2 groups of workers in China—43 workers with occupational exposure to formaldehyde and 51 without such exposure.
The researchers looked at complete blood counts and peripheral stem/progenitor cell colony formation. They also cultured myeloid progenitor cells, aiming to determine the level of leukemia-specific chromosome changes, including monosomy 7 and trisomy 8, in these cells.
The team found that workers exposed to formaldehyde had significantly lower peripheral blood cell counts and significantly elevated leukemia-specific chromosome changes in myeloid progenitor cells.
Dr Zhang and her colleagues said these results suggest “formaldehyde exposure can have an adverse effect on the hematopoietic system and that leukemia induction by formaldehyde is biologically plausible.”
Dr Mundt and his colleagues reanalyzed raw data from this study, including previously unavailable data on individual workers’ exposure to formaldehyde. Those data were recently released by the National Cancer Institute, which co-funded Dr Zhang’s study.
The reanalysis indicated that the observed differences in blood cell counts were not dependent on formaldehyde exposure. And the researchers found no association between the individual average formaldehyde exposure estimates and chromosomal abnormalities.
Dr Mundt’s team also reviewed several other publications on the health effects of formaldehyde, and they said the data, as a whole, provide “little if any evidence of a causal association between formaldehyde exposure and AML.”
