Carcinogenic polycyclic aromatic hydrocarbons in classrooms of schools: risk assessment for primary school teachers

Abstract

This study evaluated risks associated with inhalation exposure to carcinogenic PAHs for populations of primary schools teachers. Ten carcinogenic (probable, possible) PM2.5-bound PAHs were collected in indoor air of 9 classrooms at four Portuguese primary schools (PSC-PSR) during winter-spring 2014. The highest total levels of ten carcinogenic (Σ10PAH = 21.3-25.6 ng m-3) were found in classrooms at a school with busy traffic (in the surrounding streets) whereas the lowest indoor concentrations were obtained in classrooms of a school situated in residential zone (0.47-0.72 ng m-3). Dibenz[a,h]anthracene (21-29% of Σ10PAH), benzo[b]fluoranthene (13-28%) and naphthalene (5-40%) were the most abundant congeners in indoor air of classrooms, whereas benz[a]anthracene was among the least abundant PAHs (1-3%). Values of total incremental lifetime cancer risks (i.e. sum of risks of ten carcinogenic PAH congeners) were below the USEPA guideline level of 10-6 for teachers at all studied schools (independently of the duration of the employment) and thus the risks can be considered as negligible. (c) 2017 Taylor & Francis Group, London.