Somatic cell mutation in workers occupationally exposed to mercury vapors

Area of Science:

• Environmental Health
• Toxicology
• Human Genetics

Background:

• Somatic cell mutation analysis in human peripheral lymphocytes is an emerging tool for biological monitoring of occupational environments.
• Assessing the sensitivity of biomonitoring methods to mercury (Hg) body burden is crucial for worker safety.

Purpose of the Study:

• To evaluate the sensitivity of specific biomonitoring techniques to mercury exposure.
• To determine if micronucleus frequency (MN), sister chromatid exchanges (SCE), and hypoxanthine guanine phosphoribosyl transferase (HGPRT) assays reflect mercury levels in exposed workers.

Main Methods:

• Selected 30 male workers from the chloralkali industry exposed to mercury (Hg) vapors and 30 unexposed control subjects.
• Measured micronucleus frequency (MN), sister chromatid exchanges (SCE), and HGPRT mutations in human lymphocytes.
• Used urinary mercury concentration (HgU) as a biological index of exposure.

Main Results:

• Exposed workers exhibited significantly higher levels of MN (32.0 +/- 1.7), SCE (7.3 +/- 0.2), and HGPRT mutations (0.94 +/- 0.01) compared to controls.
• Urinary mercury levels correlated with increased frequencies of these genetic damage markers.

Conclusions:

• Somatic cell mutation analyses are sensitive indicators of mercury vapor exposure in occupationally exposed individuals.
• Recommends incorporating somatic cell mutation analysis into the periodic medical surveillance of workers exposed to mercury vapors.