Lung Cancer Risk after Exposure to Polycyclic Aromatic Hydrocarbons: A Review and Meta-Analysis

Abstract

Typical polycyclic aromatic hydrocarbon mixtures are established lung carcinogens, but the quantitative exposure–response relationship is less clear. To clarify this relationship we conducted a review and meta-analysis of published reports of occupational epidemiologic studies. Thirty-nine cohorts were included. The average estimated unit relative risk (URR) at 100 μg/m3 years benzo[a]pyrene was 1.20 [95% confidence interval (CI), 1.11–1.29] and was not sensitive to particular studies or analytic methods. However, the URR varied by industry. The estimated means in coke ovens, gasworks, and aluminum production works were similar (1.15–1.17). Average URRs in other industries were higher but imprecisely estimated, with those for asphalt (17.5; CI, 4.21–72.78) and chimney sweeps (16.2; CI, 1.64–160.7) significantly higher than the three above. There was no statistically significant variation of URRs within industry or in relation to study design (including whether adjusted for smoking), or source of exposure information. Limited information on total dust exposure did not suggest that dust exposure was an important confounder or modified the effect. These results provide a more secure basis for risk assessment than was previously available.

Chemical characterization of fine particulate matter emitted by peat fires in Central Kalimantan, Indonesia, during the 2015 El Niño

“…This chemical profile is in good agreement with 15 prior studies of Indonesian peat burning using laboratory measurements (Christian et al, 2003;Iinuma et al, 2007) and ambient aerosol studies in Indonesia (Fujii et al, 2015a;Fujii et al, 2015b) as well as laboratory studies of peat emissions from other locations Geron and Hays, 2013;Chen et al, 2007). (Armstrong et al, 2004;Kim et al, 2013).…”

Attributing risk burden of PM2.5-bound polycyclic aromatic hydrocarbons to major emission sources: Case study in Guangzhou, south China

“…They are ubiquitous in the atmosphere and emitted primarily from incomplete combustion of fossil fuels and biomass (Bi et al, 2003;Ravindra et al, 2008). Several PAHs have been proved to be human carcinogens and have a significant presence in particulate matter, these toxicants can deposit in the lungs and exert their carcinogenicity over long exposure periods (Collins et al, 1998;Armstrong et al, 2004). As semi-volatile persistent organic pollutants (POPs), airborne PAHs are capable of long range transport and impacting remote areas (Halsall et al, 2001;Ding et al, 2007;Liu et al, 2013).…”

Transpacific transport of benzo[a]pyrene emitted from Asia

“…Polycyclic aromatic hydrocarbons (PAHs) have been included in the Convention on Long range Transboundary Air Pollution Protocol on Persistent Organic Pollutants (United Nations Economic Commission, http://www.unece.org/env/ lrtap/pops h1.htm) and linked with human health (Armstrong et al, 2004). PAHs are mainly generated from incomplete combustion of carbonaceous bio-and fossil fuels.…”