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2-Naphthol levels and genotoxicity in rubber workers
Glenn Talaska1, Beverly Gaultney, Susan Peters
1Department of Environmental Health, University of Cincinnati College of Medicine, 3223 Eden Ave, Cincinnati, OH 45267-0056, USA. glenn.talaska@uc.edu
Toxicology Letters
|May 26, 2011
Summary
Urinary bladder cancer risk persists in rubber workers despite reduced aromatic amine exposure. This study found increased urinary 2-naphthol (2NAP) levels post-shift, especially in the curing department, suggesting polycyclic aromatic compounds (PACs) as potential carcinogens.
Area of Science:
- Occupational Health
- Environmental Toxicology
- Cancer Epidemiology
Background:
- Urinary bladder cancer has historically affected rubber workers, linked to aromatic amine exposure.
- Despite decreased exposure to known carcinogens like 2-naphthylamine, bladder cancer risk remains elevated.
- Polycyclic aromatic compounds (PACs) are investigated as potential contributors to bladder cancer in this population.
Purpose of the Study:
- To measure pre- and post-exposure urinary levels of 2-naphthol (2NAP), a metabolite of a volatile PAC.
- To assess the relationship between urinary 2NAP levels and exposure/effect markers in non-smoking rubber workers.
Main Methods:
- Collected pre- and post-exposure urine samples from 43 non-smoking rubber workers.
- Measured urinary 2-naphthol (2NAP) levels.
- Compared 2NAP levels between pre- and post-shift samples and between production and non-production workers.
- Correlated 2NAP levels with carcinogen-DNA adducts and other exposure/effect indicators.
Main Results:
- Overall mean post-shift urinary 2NAP levels were higher than pre-exposure levels, though not statistically significant (p=0.29).
- A 4.5-fold increase in post-exposure 2NAP was observed in the curing department.
- Post-shift 2NAP levels were significantly higher in production workers compared to non-production workers (p=0.02).
- Urinary 2NAP levels did not correlate with carcinogen-DNA adducts or other exposure/effect measures.
Conclusions:
- Post-shift urinary 2NAP levels increase in rubber workers, particularly in the curing department.
- While not statistically significant overall, these findings suggest PAC exposure in the rubber industry.
- Urinary 2NAP levels did not serve as a reliable biomarker for carcinogen-DNA adducts in this study.
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