Micronuclei frequencies in exfoliated nasal mucosa cells from pathology and anatomy laboratory workers exposed to formaldehyde

Formaldehyde (FA) is a widely used industrial chemical. Sufficient evidence exists to consider FA as an animal carcinogen. A possible causal role for FA may be considered likely for cancer of the nasopharynx and the nasal cav ities in humans. The frequency of micronuclei (MN) in cells of the nasal mu cosa was evaluated for 23 individuals in pathology and anatomy laboratories exposed to FA. Twenty-five healthy subjects were selected from the univers ity and hospital staff as a control group. The measured air concentrations of FA in the breathing zone of the laboratory workers were between 2 and 4 ppm. The mean +/- SD values of nasal mucosa MN (parts per thousand) frequen cy from exposed and controls were 1.01 +/- 0.62 and 0.61 +/- 0.27, respecti vely (p < 0.01). Effect of smoking, age, sex and duration of exposure on th e genotoxicity parameters analyzed were also evaluated. Our data suggest th at low level exposure to FA is associated with cytogenetic changes in epith elial cells of the nasal region and that nasal mucosa cells exposed through respiration is an important target of FA-induced genotoxic effects.