Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Sci Total Environ. 2022 Apr 20;818:151789. doi: 10.1016/j.scitotenv.2021.151789. Epub 2021 Nov 19.
Using an improved multimedia fate model, this study simulated the spatial distributions, partitioning behaviors, and mass exchanges of PAH (16 species with priority by the USEPA) in multiple environmental compartments in the coastal regions of the Bohai and Yellow Seas, Northern China. The model predictions generally matched well with the measured results, as the deviations of most points were within one order of magnitude in the air, freshwater, and 3 soil compartments. The estimated concentrations of ΣPAH in the northern part were higher than those in the southern part, which was consistent with the emissions of each part. Approximately 97.6% of the ΣPAH mass was distributed in soils; therefore, soils served as the dominant sink of PAH. The estimated net flux of ΣPAH from air to soil ranged from 0.4 to 10.7 mg/m/year (an average of 3.2 mg/m/year), and the estimated flux of deposition from air to soil fell in the range of 0.4-10.8 mg/m/year (an average of 3.2 mg/m/year), which served as the dominant process at the air-soil interface. The estimated net flux of ΣPAH from air to freshwater ranged from -15.3 to 9.4 mg/m/year (an average of -0.3 mg/m/year), and the reversed volatilization flux from freshwater to air ranged from 0.01 to 21.1 mg/m/year (an average of 3.7 mg/myear). This situation indicated notable spatial variations and volatilization as the main process affecting the direction of net flux at the air-freshwater interface. Deterministic risk assessment and probabilistic risk assessment were conducted. The overall health risks of the studied regions were acceptable, while the excess lifetime cancer risk (ELCR) by air inhalation was greater than that by soil ingestion. CAPSULE: Multimedia fate model-predicted distributions and compositions of PAH in different compartments, compartmental exchange fluxes and directions, and deterministic and probabilistic ELCR via different exposure pathways were assessed.
利用改进的多介质归趋模型，本研究模拟了中国北方渤海和黄海沿海地区多环境介质中多环芳烃（PAH）（美国环保署优先的 16 种物质）的空间分布、分配行为和质量交换。模型预测结果与实测结果总体吻合较好，大部分点位的偏差在空气、淡水和 3 种土壤介质中均在一个数量级内。北部地区ΣPAH 的估算浓度高于南部地区，这与各部分的排放情况一致。约 97.6%的ΣPAH 质量分布在土壤中；因此，土壤是 PAH 的主要汇。空气到土壤的ΣPAH 净通量估算值范围为 0.4 到 10.7mg/m/year（平均值为 3.2mg/m/year），空气到土壤的沉降通量估算值范围为 0.4-10.8mg/m/year（平均值为 3.2mg/m/year），这是空气-土壤界面的主要过程。空气到淡水的ΣPAH 净通量估算值范围为-15.3 到 9.4mg/m/year（平均值为-0.3mg/m/year），而淡水到空气的反向挥发通量范围为 0.01 到 21.1mg/m/year（平均值为 3.7mg/m/year）。这种情况表明，空气-淡水界面的净通量方向受到显著的空间变化和挥发作用的影响。进行了确定性风险评估和概率风险评估。研究区域的整体健康风险是可以接受的，而通过空气吸入的终生超额癌症风险（ELCR）大于通过土壤摄入的风险。结论：通过不同的暴露途径，评估了多介质归趋模型预测的不同介质中 PAH 的分布和组成、分室交换通量和方向，以及确定性和概率性 ELCR。
