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. FY2017 focused on review of FY2016 survey experience and results to evaluate if revision of protocol was necessary, contact with industry representatives, and recruitment of companies. Several dozen contacts were made to identify companies for site visits. Once companies were successfully recruited and agreed to participate, three additional field surveys were conducted. Chemical and biological sample analysis from these visits are ongoing.