Studying Blood Toxicity in Workers Exposed to Formaldehyde

Research in industrial workers and professionals exposed to formaldehyde suggests that occupational exposure to this important chemical is associated with increased risk for myeloid leukemia. However, there is still uncertainty about the biologic plausibility of the association because of questions regarding the ability of formaldehyde, which is extremely reactive, to directly or indirectly cause toxicity to the bone marrow. There have been several relatively small studies of the impact of occupational formaldehyde exposure on peripheral blood cells that found some evidence that peripheral blood cells of the myeloid lineage (i.e., granulocytes, platelets) were significantly decreased in exposed workers. We propose to follow-up these findings in a relatively large study population in China. We will study hematologic parameters in 240 higher exposed workers (>1 ppm), 240 workers exposed to lower levels of formaldehyde (0.3 to 1 ppm), and a group of 240 unexposed controls frequency-matched to exposed workers. This study will make an important contribution to our understanding of the leukemogenic potential of formaldehyde, which has important public health and regulatory implications.