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 (PAHs), some of which are listed as Group 1 Human Carcinogens by the International Agency for Research on Cancer (IARC). The potential for occupational exposure to airborne levels of PAHs may be present during coal tar sealant (CTS) application work. There are numerous workers potentially exposed to coal tar pitch volatiles (considered potential occupational carcinogens by NIOSH), but occupational exposure levels of CTS Applicators are unknown and require assessment. Exposure to coal tar PAHs is being 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 (optional); collection and analysis of skin wipe samples for assessment of dermal exposure. Bulk samples of CTS sealant used during surveys have been collected for use in evaluation of polycyclic aromatic mixtures in separate research studies. Contact with industry representatives, and recruitment of companies identified several sites suitable for this study. To date, five field surveys have been conducted and 72 worker-days have been monitored. A sixth site survey has been scheduled for October, 2018. Chemical and biological sample analyses from the first set of site visits have been completed and the analyses of the last two job surveys are ongoing.