Occupational exposure to formaldehyde was found to be associated with increased death rates from myeloid leukemia in 2 recent studies published by researchers at the National Cancer Institute. Formaldehyde is widely used in construction materials, manufacturing, and consumer products, and for embalming in the funeral industry. Millions of workers and consumers are regularly exposed to various concentrations of the chemical.The 2 studies, published in the Journal of the National Cancer Institute (2009;101:751-761 and 2009;101:1696-1708, found an elevated mortality rate from myeloid leukemia in individuals exposed to formaldehyde in manufacturing settings or the funeral industry. In both studies, the risk was associated with high peak exposure levels before 1980."Duration of embalming practice and related formaldehyde exposures in the funeral industry were associated with statistically significantly increased risk for mortality from myeloid leukemia," writes Michael Hauptmann, PhD, lead author and a biostatistician in the department of bioinformatics and statistics at the Netherlands Cancer Institute in Amsterdam, the Netherlands."The significance of these findings," Dr. Hauptmann says, "is that an enormously economically important chemical that is very useful for producing many things seems to be carcinogenic. There are bodies like the [World Health Organization] that have accepted that there is sufficient evidence that [formaldehyde] is carcinogenic. It not only causes a very rare cancer, nasopharyngeal cancer, but also leukemia. That means there is, in essence, a problem and this chemical should be replaced."According to the Hauptmann et al study of embalmers, the mortality rate from myeloid leukemia increased significantly with the number of years of embalming (P for trend, .020) and with increasing peak formaldehyde exposure (P for trend, .036). Compared with study subjects who had conducted fewer than 500 lifetime embalmings, mortality from myeloid leukemia was found to be elevated among those who performed embalmings for more than 34 years (odds ratio [OR], 3.9; 95% confidence interval [95% CI], 1.2-12.5 [P ϭ .024]), those who performed more than 3068 embalmings (OR, 3.0; 95% CI, 1.0-9.2 [P ϭ .057]), and those whose estimated cumulative formaldehyde exposure exceeded 9253 parts per million (ppm)-hours (OR, 3.1; 95% CI, 1.0-9.6 [P ϭ .047]).In 2003, Dr. Hauptmann's team conducted a cohort study of industrial workers who worked with formaldehyde in manufacturing and production (J Natl Cancer Inst. 2003;95:1615-1623. "We also found about a 3-fold risk for those in the highest category of peak exposure to formaldehyde compared to people who had little exposure to formaldehyde. They tripled their risk of dying from myeloid leukemia," he says."So far, we only have studies among people who are occupationally exposed," adds Dr. Hauptmann. "Often people who are occupationally exposed have higher levels of exposure than people who are environmentally exposed in their homes. Among people who work with formaldehyde, we ...
