Polycyclic aromatic hydrocarbons in airborne particulate matter samples from Hanoi, Vietnam: Particle size distribution, aryl hydrocarbon ligand receptor activity, and implication for cancer risk assessment. (October 2021)

• Record Type: Journal Article
• Authors: Trung, Nguyen Thanh; Anh, Hoang Quoc; Tue, Nguyen Minh; Suzuki, Go; Takahashi, Shin; Tanabe, Shinsuke; Khai, Nguyen Manh; Hong, Tran Thi; Dau, Pham Thi; Thuy, Pham Chau; Tuyen, Le Huu
• Is Part Of: Chemosphere. Volume 280(2021)
• Publication Date: 2021-10
• Subjects: PAHs -- Methylated PAHs -- PAH-CALUX -- Airborne particulate matter -- Hanoi; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.130720
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Concentrations and profiles of unsubstituted and methylated polycyclic aromatic hydrocarbons (PAHs and Me-PAHs) were analyzed in airborne particulate matter (PM) samples collected from high-traffic roads in Hanoi urban area. Levels of PAHs and Me-PAHs ranged from 210 to 660 (average 420) ng/m 3 in total PM, and these pollutants were mainly associated with fine particles (PM2.5 ) rather than coarser ones (PM > 10 and PM10 ). Proportions of high-molecular-weight compounds (i.e., 5- and 6-ring) increased with decreasing particle size. Benzo[b+k]fluoranthene, indeno[1, 2, 3-cd]pyrene, and benzo[ghi]perylene were the most predominant compounds in the PM2.5 samples. In all the samples, Me-PAHs were less abundant than unsubstituted PAHs. The PAH-CALUX assays were applied to evaluate aryl hydrocarbon receptor (AhR) ligand activities in crude extracts and different fractions from the PM samples. Benzo[a]pyrene equivalents (BaP-EQs) derived by the PAH-CALUX assays for low polar fractions (mainly PAHs and Me-PAHs) ranged from 300 to 840 ng/m 3, which were more consistent with theoretical values derived by using PAH-CALUX relative potencies (270–710 ng/m 3 ) rather than conventional toxic equivalency factor-based values (22–69 ng/m 3 ). Concentrations of PAHs and Me-PAHs highly correlated with bioassay-derived BaP-EQs. AhR-mediated activities of more polar compounds and interaction effects between PAH-related compounds were observed. By using PAH-CALUX BaP-EQs, the ILCR values ranged from 1.0 × 10 −4 to 2.8 × 10 −4 for adults and from 6.4 × 10 −5 to 1.8 × 10 −4 for children. Underestimation of cancer risk can be eliminated by using effect-directed method (e.g., PAH-CALUX) rather than chemical-specific approach. Graphical abstract: Image 1 Highlights: PAHs, Me-PAHs, and AhR ligand activities were measured in airborne PM samples. Pollutant concentrations and induced toxicities were mainly associated with PM2.5 . 5- and 6-ring compounds (e.g., Bb + kF, IP, BP) dominated PAH patterns in PM2.5 . Significant gaps between conventional and bioassay-derived BaP-EQs were found. Application of effect-directed method can reduce risk underestimation of PAHs.