Radiation Protection Institute, Ghana Atomic Energy Commission, P.O. Box LG80, Legon, Accra, Ghana.
Faculty of Engineering, Queensland University of Technology (QUT), GPO Box 2434, Brisbane, 4001, Queensland, Australia.
Environ Pollut. 2022 Sep 1;308:119705. doi: 10.1016/j.envpol.2022.119705. Epub 2022 Jul 4.
The distribution and fate of hazardous polycyclic aromatic hydrocarbons (PAHs) and their associated transformed PAHs products (TPPs) notably carbonyl-PAHs (CPAHs), hydroxy-PAHs (HoPAHs), and nitro-PAHs (NPAHs) on urban road surfaces are influenced by diverse factors to varying extent. The pollutants are eventually transported to urban receiving waters via stormwater runoff posing risks to human and ecosystem health. In order to formulate an effective mitigation strategy, it is essential to comprehensively examine the role of both inherent and external factors in the distribution and fate of these hazardous pollutants, and thus, the need for this study. The research study showed that commercial land use has the highest cumulative concentration of PAHs and TPPs. Antecedent dry days (ADDs) has an inverse influence on the distribution of the total concentrations of low-molecular weight PAHs (LMW-PAHs), PAHs, and (PAHs + TPPs) irrespective of the type of land use, whilst there was no major influence on the total concentrations of high molecular weight PAHs (HMW-PAHs), and TPPs. The high volatility of LMW-PAHs compared to HMW-PAHs is considered to account for the decreasing concentration of LMW-PAH with increasing ADD. Particle size range has significant inverse influence on the cumulative concentration of pollutants across all land uses, since smaller particles are characteristically associated with larger surface area leading to the higher sorption of pollutants. Multivariate analysis of the influential factors indicated that two particle size ranges (0.45-150 μm and 150-425 μm) constitute the major influential factors on the distribution and fate of PAHs and TPPs in urban road dust. Greater quantum of pollutants are sorbed to the 0.45-150 μm particles due to the relatively higher specific surface area (SSA), concentration of total organic carbon (TOC) and total suspended solids (TSS) concentration. Therefore, it is critical to effectively remove finer particles from road surfaces in order to reduce exposure to hazardous pollutants.
城市道路表面上多环芳烃（PAHs）及其相关转化产物（TPPs），尤其是羰基 PAHs（CPAHs）、羟基 PAHs（HoPAHs）和硝基 PAHs（NPAHs）的分布和归宿受到多种因素的影响，程度各不相同。这些污染物最终通过雨水径流被输送到城市受纳水体中，对人类和生态系统健康构成威胁。为了制定有效的缓解策略，必须全面研究内在和外在因素在这些危险污染物分布和归宿中的作用，因此需要进行这项研究。研究表明，商业用地具有最高的 PAHs 和 TPPs 累积浓度。不论土地利用类型如何，前期干燥天数（ADDs）对低分子量 PAHs（LMW-PAHs）、PAHs 和（PAHs+TPPs）的总浓度分布都有反作用，而对高分子量 PAHs（HMW-PAHs）和 TPPs 的总浓度分布则没有重大影响。与 HMW-PAHs 相比，LMW-PAHs 的高挥发性被认为是随着 ADD 的增加而导致 LMW-PAHs 浓度降低的原因。粒径范围对所有土地利用类型的污染物累积浓度都有显著的反作用，因为较小的颗粒通常与较大的表面积有关，从而导致污染物的更高吸附。影响因素的多元分析表明，两个粒径范围（0.45-150μm 和 150-425μm）是影响城市道路灰尘中 PAHs 和 TPPs 分布和归宿的主要因素。由于相对较高的比表面积（SSA）、总有机碳（TOC）浓度和总悬浮固体（TSS）浓度，更多的污染物被吸附到 0.45-150μm 的颗粒上。因此，有效地从道路表面去除更细的颗粒对于减少接触危险污染物至关重要。
