Biomonitoring Study of Dry Cleaning Workers Using Cytogenetic Tests and the Comet Assay

Abstract

Perchloroethylene (PCE) is the main solvent used in the dry cleaning industry worldwide. The aim of the present work was to evaluate the genotoxic potential of occupational exposure to PCE in dry cleaning workers. The study was carried out in 59 volunteers (30 workers, 29 controls). The genotoxic effect was evaluated by analyzing chromosome aberrations (CAs), and micronuclei (MN) and DNA damage (assessed by the comet assay) in peripheral blood lymphocytes. Environmental monitoring of exposure was carried out on personal breathing zone air samples collected during two consecutive working days by measuring the concentration of PCE air levels. The mean PCE concentration in workplace air of dry cleaning workers was 31.40 mg/m³. There were no significant differences in CA frequency between dry cleaning workers and the controls, but analysis showed a significant association of CA frequency with employment duration and frequency of exposure to PCE. The MN frequency and DNA damage detected by alkaline comet assay were significantly increased in dry cleaning workers compared to the controls. The results suggest that (a) chronic occupational exposure to dry cleaning solvents below permissible occupational exposure limit of 70 mg/m³ (i.e., ∼10.3 ppm) may lead to an increased risk of genetic damage among dry cleaning workers, and (b) CA, MN tests, and comet assay are useful to monitor populations exposed to low doses of PCE.

Keywords:

• perchloroethylene
• lymphocytes
• chromosome aberrations
• micronuclei
• comet assay

Acknowledgments

We are grateful to Rita Karpičiūtė from the Institute of Oncology, Vilnius University, for her assistance throughout the study and for performing blood sample collection. The authors express their sincere thanks to Danutė Adamonienė, head of the Laboratory for Chemical Investigations, Institute of Hygiene, Vilnius, for providing facilities for the study. The authors also thank all the volunteers who participated in this study.