Lymphocyte subsets and sister-chromatid exchanges in the students exposed to formaldehyde vapor

The present report evaluates the effects of formaldehyde (EA) exposure on peripheral lymphocytes by using both genetic and immunological parameters. Twenty-three non-smoking students in the study had inhalation exposure to 0.508 +/- 0.299mg/m(3) of FA for a period of 8 weeks (3h x 3 times each week) during anatomy classes. As for composition of lymphocyte subsets after FA exposure, significant increase was found in the percentage of CD19(B cells), while significant decrease was observed in CD,(total T cells), CD4(T helper-inducer cells), and CD8(T cytotoxic-suppressior cells) with a P < 0.01. increase in the ratio of T-helper-inducer cells to T-cytotoxic-suppressor cells (T-4/ T-8) was also observed with statistical significance after exposure (P < 0.001). In the meanwhile, no significant difference (P > 0.05) was reported between lymphocyte proliferation rate and sister-chromatid exchange (SCE) at the exposure level and duration. It is suggested that the lymphocyte subsets may be most susceptible to the effects of FA, though a single immunological endpoint is rarely related with pathophysiological interpretation.