Assessment of Occupational Exposure to Coal tar pitch volatiles containing PAHs in Coal Tar Sealant Applications

National Institute Of Environmental Health Sciences

Investigators

Abstract

Coal tar is a complex mixture of chemicals known to include a variety of Polycyclic Aromatic Hydrocarbons, some of which are listed as Group 1 Human Carcinogens by the International Agency for Research on Cancer (IARC). Occupational exposure assessments suggest that significant airborne levels may be present during the actual coal tar sealant application work. There is a large workforce potentially exposed to coal tar pitch volatiles (considered potential occupational carcinogens by NIOSH), but occupational exposure levels are unknown and require assessment. Exposure to coal tar PAHs will be assessed using: occupational air sampling and analysis to quantify exposures to PAHs/coal tar pitch volatiles; collection and analysis of urine samples to allow assessment of biomarkers of internal PAH exposure levels; collection of blood samples for analysis of biomarkers of effect potentially related to PAH exposure; collection and analysis of dermal wipe samples for assessment of dermal exposure. Bulk samples of sealant used during surveys will be provided to NTP for use in evaluation of polycyclic aromatic mixtures in a separate research program. During FY2015 a draft protocol was developed and peer review was completed. Tripartite and IRB review of the protocol is in progress. Contacts are being made to identify companies for site visits. Once review is complete and companies are recruited, field surveys will begin. Pre- and post-shift urine samples will be analyzed for 1OHP, using the ELISA (3-4 ring) PAH analysis method. NIOSH will analyze for additional metabolites using the ELISA (5-6 ring) PAH analysis method. NIOSH will also analyze each urine sample for the metabolites: 1-naphthol; and 2-naphthol. Urine samples will also be analyzed for cotinine and creatinine.