Barhoumi Badreddine, Guigue Catherine, Touil Soufiane, Johnson-Restrepo Boris, Driss Mohamed Ridha, Tedetti Marc
Laboratory of Hetero-Organic Compounds and Nanostructured Materials (LR18ES11), Department of Chemistry, Faculty of Sciences of Bizerte, University of Carthage, 7021 Zarzouna, Tunisia; Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288 Marseille, France.
Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288 Marseille, France.
Sci Total Environ. 2023 Jun 25;879:162986. doi: 10.1016/j.scitotenv.2023.162986. Epub 2023 Mar 22.
Many studies have focused on aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (AHs and PAHs) in different environmental compartments, especially atmospheric particles (aerosols), due to their adverse effects on the environment and human health. However, much less information is currently available on the content of AHs and PAHs in the atmospheric gas phase, which is a major reservoir of volatile and photoreactive compounds. Here, for the first time, we assessed the levels, gas-particle partitioning, human health risks and seasonal variations of AHs and PAHs in the atmospheric gas-phase of Bizerte city (Tunisia, North Africa) over a one-year period (March 2015-January 2016). ΣPAH concentration in the gas phase over the period ranged from 6.7 to 90.6 ng m and on average was 2.5 times higher in the cold season than in the warm season. ΣAH concentration in the gas phase over the period ranged from 14.0 to 35.9 ng m, with no clear seasonal variations. In the gas phase, hydrocarbons were dominated by low-molecular-weight (LMW) compounds, i.e. 3- and 4-ring for PAHs and < n-C for AHs. Gas-phase concentrations of PAHs and AHs accounted for up to 80 % of the total (gas + particle phases) atmospheric concentrations of PAHs and AHs. Further analysis of gas-particle partitioning showed that LMW hydrocarbons preferential accumulated in the gas phase, and that gas-particle partitioning was not in equilibrium but dominated by absorption processes into the aerosol organic matter. Benzo[a]pyrene toxic equivalency quotient (BaP-TEQ) in the gas phase represented on average 37 % of the total atmospheric BaP-TEQ concentration, which was always higher in the cold season. Atmospheric gas is a significant factor in the risks of cancer associated with inhalation of ambient air. The Monte Carlo simulation-based exposure assessment model predicted that outdoor air exposure to PAHs does not pose a cancer risk to infants, but the children, adolescent, and adult populations may face a lower cancer risk during the warm season and a higher risk in the cold season.
许多研究聚焦于不同环境介质中的脂肪烃和多环芳烃（AHs和PAHs），尤其是大气颗粒物（气溶胶），因为它们会对环境和人类健康产生不利影响。然而，目前关于大气气相中AHs和PAHs含量的信息要少得多，而大气气相是挥发性和光反应性化合物的主要储存库。在此，我们首次评估了突尼斯（北非）比塞大市大气气相中AHs和PAHs在一年期间（2015年3月 - 2016年1月）的含量、气 - 粒分配、对人类健康的风险及季节变化。在此期间气相中ΣPAH浓度范围为6.7至90.6 ng m，冷季平均浓度比暖季高2.5倍。在此期间气相中ΣAH浓度范围为14.0至35.9 ng m，无明显季节变化。在气相中，烃类以低分子量（LMW）化合物为主，即PAHs为三环和四环，AHs为小于正构烷烃。PAHs和AHs的气相浓度占PAHs和AHs大气总浓度（气相 + 颗粒相）的比例高达80%。气 - 粒分配的进一步分析表明，LMW烃类优先在气相中积累，且气 - 粒分配并非处于平衡状态，而是以气溶胶有机物的吸收过程为主导。气相中苯并[a]芘毒性当量商（BaP - TEQ）平均占大气总BaP - TEQ浓度的37%，冷季时该值始终更高。大气气相是与吸入环境空气相关的癌症风险的一个重要因素。基于蒙特卡洛模拟的暴露评估模型预测，室外空气暴露于PAHs对婴儿不会构成癌症风险，但儿童、青少年和成年人群在暖季可能面临较低的癌症风险，而在冷季风险较高。
