Biologic markers in ethylene oxide-exposed workers and controls.

Area of Science:

• Occupational Health
• Toxicology
• Biomonitoring

Background:

• Ethylene oxide (EtO) is a known mutagen and carcinogen.
• Occupational exposure to EtO occurs in sterilization units.
• Assessing health effects of low-level EtO exposure is crucial.

Purpose of the Study:

• To evaluate the association between low-level occupational EtO exposure and various biological markers in sterilization workers.
• To investigate the relationship between EtO exposure, DNA damage, DNA repair capacity, and potential genetic susceptibility.
• To determine if current Occupational Safety and Health Administration (OSHA) standards are adequately protective.

Main Methods:

• Biomonitoring of 34 sterilization workers and 23 controls using blood samples.
• Measurement of EtO-hemoglobin adducts (EtO-Hb), sister-chromatid exchanges (SCEs), micronuclei, chromosomal aberrations (CAs), DNA single-strand breaks (SSBs), and DNA repair index.
• Collection of environmental, occupational, and smoking histories; personal monitoring for EtO exposure.

Main Results:

• Significant associations found between EtO exposure (below 1 ppm) and increased EtO-Hb adducts and SCEs, independent of smoking.
• Suppressed DNA repair capacity was observed in EtO-exposed individuals.
• A strong correlation was noted between EtO-Hb adducts and SCE markers, indicating a link between dose and genotoxic response.
• No significant elevation in micronuclei, CAs, or SSBs was detected.

Conclusions:

• Low-level occupational EtO exposure, even below 1 ppm, induces significant genotoxic effects.
• The current OSHA standard for EtO may not provide adequate protection for workers.
• Biomarkers like EtO-Hb and SCEs are sensitive indicators of EtO exposure and its biological effects.