The utility of naphthyl-keratin adducts as biomarkers for jet-fuel exposure

Abstract

We investigated the association between biomarkers of dermal exposure, naphthyl-keratin adducts (NKA), and urine naphthalene biomarker levels in 105 workers routinely exposed to jet-fuel. A moderate correlation was observed between NKA and urine naphthalene levels (p = 0.061). The NKA, post-exposure breath naphthalene, and male gender were associated with an increase, while CYP2E1*6 DD and GSTT1-plus (++/+−) genotypes were associated with a decrease in urine naphthalene level (p < 0.0001). The NKA show great promise as biomarkers for dermal exposure to naphthalene. Further studies are warranted to characterize the relationship between NKA, other exposure biomarkers, and/or biomarkers of biological effects due to naphthalene and/or PAH exposure.

Keywords::

• Biomarkers
• CYP2E1
• dermal exposure
• glutathione S-transferase mu 1 (GSTM1)
• glutathione S-transferase theta 1 (GSTT1)
• jet fuel (JP-8)
• keratin adduct
• NAD(P)H:quinone oxidoreductase (NQO1)
• 1-naphthol
• 2-naphthol
• naphthalene
• urine

Acknowledgments

We are especially grateful to the workers for their participation in the study. The United States Environmental Protection Agency through its Office of Research and Development collaborated in the research described here.

Declaration of interest

The authors report no conflicts of interest. Mention of company names and/or products does not constitute endorsement by the National Institute for Occupational Safety and Health. The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health. This work was supported by NIEHS (P42ES05948), NIOSH (T42/CCT422952 and T42/008673), and the NIEHS Intramural Research Program. It has been subjected to United States Environmental Protection Agency review and approved for publication. This article may be the work product of an employee or group of employees of the National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH); however, the statements, opinions or conclusions contained therein do not necessarily represent the statements, opinions or conclusions of NIEHS, NIH, or the United States government.