屋面雨水集汇过程中新污染物分布及归趋特性

雨水中新污染物（ECs）识别逐渐受到广泛关注,掌握其在降水过程赋存及迁变特性成为雨水资源化利用的关键. 选取典型屋面,研究了2023年春季3~5月期间6场降雨事件不同集汇过程中雨水水质状况及ECs赋存差异,采用主成分分析（PCA）和相关性分析,探明了屋面雨水集汇过程中ECs归趋特性. 结果表明,54种目标ECs在净湿沉降、干湿沉降和屋面径流过程中共检出44种,总浓度范围为63.0~432.4 ng·L^-1（平均值为166.8 ng·L^-1）. 其中,双酚A（BPA）浓度水平最高,其范围为14.7~265.6 ng·L^-1（平均值为62.5 ng·L^-1）,其次为氧氟沙星（OFX）和甲氧基肉桂酸乙基己酯（EHMC）；溶解性有机质（DOM）、氮污染物和颗粒物是影响ECs赋存特性的重要因子,Mantel相关系数最高可达0.98（P<0.01）；初期雨水集汇过程中净湿沉降的ECs浓度最高,而后期干湿沉降和屋面径流的ECs浓度较高,干、湿沉降对屋面径流的ECs平均贡献率分别为21.48%和78.52%,药品与个人护理品（PPCPs）、内分泌干扰物（EDCs）和农药等在集汇过程中超30%沉积在屋面. 研究结果可为城市屋面径流中的ECs识别和控制以及雨水安全利用提供科学理论依据.

Identification and Derivation of Emerging Contaminants in the Roof Rainwater Confluence

To identify emerging contaminants （ECs） in rainwater is a topic that has gradually received widespread attention. Rainwater resources, specifically urban roofs, play a crucial role in utilizing rainwater efficiently by understanding the occurrence and migration characteristics of pollutants in precipitation. This study selected a typical roof and studied the differences in rainwater quality and pollution occurrence at different collection stages during six rainfall events from March to May in 2023. Principal component analysis （PCA） and correlation analysis were used to explore the distribution, migration, and transformation of ECs in the collection process of roof rainwater. The findings revealed the presence of 44/54 ECs in wet deposition, dry and wet deposition, and roof runoff processes, with a total concentration range of 63.0 to 432.4 ng·L^-1 and an average concentration of 166.8 ng·L^-1. Notably, bisphenol A （BPA） exhibited the highest concentration, ranging from 14.7 to 265.6 ng·L^-1, with an average concentration of 62.5 ng·L^-1, followed by ofloxacin （OFX） and ethylhexyl methoxycinnamate （EHMC）, with detected concentrations up to 45.5 ng·L^-1 and 44.8 ng·L^-1. Dissolved organic matter （DOM）, nitrogen pollutants, and particulate matter were important factors affecting the occurrence characteristics of ECs, with a mantel correlation coefficient of up to 0.98 （P<0.01）. Based on the analysis of different rainfall events and collection stages, variations were observed in the accumulation pathways and contribution ratios of different pollutants. The wet deposition exhibited the highest content of ECs in the initial stage, whereas the dry and wet deposition and roof runoff processes displayed higher ECs content in the later stages. Additionally, the average ECs contribution rates of dry and wet deposition to roof runoff were 21.48% and 78.52%, respectively. Due to the influence of roof material and surface roughness retention performance, over 30% of ECs, including pharmaceuticals and personal care products （PPCPs）, endocrine-disrupting compounds （EDCs）, and pesticides, were deposited on the roof during the runoff collection. The results of this research can provide the theoretical foundation and technical support for the identification and control of ECs in urban roof runoff and for the safe storage of rainwater.