Oxygenated and Nitrated Polycyclic Aromatic Hydrocarbons in Ambient Air—Levels, Phase Partitioning, Mass Size Distributions, and Inhalation Bioaccessibility

Abstract

Among the nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) are some of the most hazardous substances to public health, mainly because of their carcinogenicity and oxidative potential. Despite these concerns, the concentrations and fate of NPAHs and OPAHs in the atmospheric environment are largely unknown. Ambient air concentrations of 18 NPAHs, 5 quinones, and 5 other OPAHs were determined at two urban and one regional background sites in central Europe. At one of the urban sites, the total (gas and particulate) concentrations of Σ10OPAHs were 10.0 ± 9.2 ng/m3 in winter and 3.5 ± 1.6 ng/m3 in summer. The gradient to the regional background site exceeded 1 order of magnitude. Σ18NPAH concentrations were typically 1 order of magnitude lower than OPAHs. Among OPAHs, 9-fluorenone and (9,10)-anthraquinone were the most abundant species, accompanied by benzanthrone in winter. (9,10)-Anthraquinone represented two-thirds of quinones. We found that a large fraction of the target substance particulate mass was carried by submicrometer particles. The derived inhalation bioaccessibility in the PM10 size fraction is found to be ≈5% of the total ambient concentration of OPAHs and up to ≈2% for NPAHs. For 9-fluorenone and (9,10)-anthraquinone, up to 86 and 18%, respectively, were found at the rural site. Our results indicate that water solubility could function as a limiting factor for bioaccessibility of inhaled particulate NPAHs and OPAHs, without considerable effect of surfactant lipids and proteins in the lung lining fluid.

Polycyclic aromatic hydrocarbons (PAHs) and oxy- and nitro-PAHs in ambient air of the Arctic town Longyearbyen, Svalbard

“…The PAH emissions profile was dominated by Nap and Phe, accounting for 53 % and 27 % of 16 PAHs, followed by Flu, Flt, and Pyr. Nap and Phe are often reported as major emitted compounds from power plants equipped with analogous exhaust cleaning systems and/or burning the same type of coal (Hsu et al, 2016;Li et al, 2016;Wang et al, 2015). A similar PAH emissions profile was reported by Hsu et al (2016) for the power plant in central Taiwan (Table S12).…”

“…Among measured oxy-PAHs, concentrations of 9-Flu and 9,10-AntQ were the highest in the present study. The 9-Flu level (270.3±146.9 pg m −3 at UNIS and 139.4±24.9 pg m −3 in Adventdalen) was a factor of 3 higher than reported for Pallas and Råö (southern Sweden) background stations (Brorström-Lundén et al, 2010), while 9,10-AntQ (163.5 ± 57.4 pg m −3 at UNIS and 71.7 ± 39.2 pg m −3 in Adventdalen) in Longyearbyen was equal to the winter levels in central European background air (Lammel et al, 2020). The sum of oxy-PAHs detected at UNIS was similar to rural sites in eastern England (Alam et al, 2014) and the central Czech Republic (Lammel et al, 2020) but was significantly lower than in rural southern China (B. and the French Alps (Albinet et al, 2008).…”

“…Currently, there is no PAH emissions standard for coal-fired power plants in Norway. However, compared to the Canadian emission limits of PAHs for municipal solid waste incinerators of 5 µg m −3 (Li et al, 2016), the Longyearbyen PP emissions are a factor of 3 lower. About 94 % of 16 PAHs were emitted in a gas phase, in agreement with earlier studies (Li et al, 2016;Wang et al, 2015;Yang et al, 1998).…”

“…However, compared to the Canadian emission limits of PAHs for municipal solid waste incinerators of 5 µg m −3 (Li et al, 2016), the Longyearbyen PP emissions are a factor of 3 lower. About 94 % of 16 PAHs were emitted in a gas phase, in agreement with earlier studies (Li et al, 2016;Wang et al, 2015;Yang et al, 1998). The emission profile of the Longyearbyen PP is dominated by LMW PAHs (two and three rings), which represents 89 % of 16 PAHs emission; high molecular-weight (HMW) PAHs (5-7 rings) were not detected, likely due to their low vapour pressure and thus association with particles.…”

“…Source identification based on diagnostic ratios derived from total (G+P) concentrations; averages of individual ratio values (n = 6) with standard deviation are presented. Kuo et al (2013) the rural site in the Czech Republic which is representative of central European background levels (Lammel et al, 2020).…”