Tang Chun-Xue, Tang Min-Qi, Wu Chen-Chou, Li Cheng, Cai Ming-Hong, Bao Lian-Jun, Zeng Eddy Y
Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 511443, China.
Institute of Quality Standard and Testing Technology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
J Hazard Mater. 2025 Aug 15;494:138708. doi: 10.1016/j.jhazmat.2025.138708. Epub 2025 May 24.
The size-dependent gas-particle partitioning of transformation products (TPs) from organophosphate esters (OPEs) and the transform potential for OPEs to TPs in ambient atmosphere remain under-investigated. To fill this knowledge gap, we analyzed gaseous and size-fractionated particle samples collected from Beijing, Shanghai, and Guangzhou in China under different meteorological conditions. The concentrations of OPEs were comparable to those in other major cities worldwide, but the levels of TPs were lower than those in these cities. The Li-Ma-Yang model predicted well the size-fractionated gas-particle partition coefficients (K) of OPEs and TPs with log K > 9.1. Multiple linear regression model incorporating relative humidity narrowed the gap between predicted and observed K of OPEs with log K < 9.1, but still underestimated the K values. Hence, humidity-dependent water film adsorption and transformation of these OPEs should be included in future gas-particle partition modeling, especially in fine particles. Size distributions in concentration ratios of nine pairs of OPE to TP were not unified. Temperature exhibited negative effects on gas-particle partitioning of TPs, and inhibited the transformation of tris(2-chloropropyl) phosphate (TCIPP) to bis(1-chloro-2-propyl) phosphate (BCIPP) and triphenyl phosphate (TPhP) to 4-hydroxyphenyl diphenyl phosphate (4-OH-DPHP) in the particulate phase. Gaseous TPs contributed more to the human inhalation health risks of OPEs than particle-bound TPs. These findings are significant for comprehending the fate of atmospheric TPs in urban environment. ENVIRONMENTAL IMPLICATION: Transformation products (TPs) of organophosphate esters (OPEs) exhibit comparable or even enhanced toxicity relative to OPEs, but their atmospheric behavior remains incompletely understood. In the present study, gaseous and size-fractionated particulate samples were collected in Beijing, Shanghai, and Guangzhou to explore the gas-particle partitioning behavior of TPs and their transformation potential from OPEs. Results indicated that relative humidity influenced the gas-particle partitioning behavior of compounds with log K < 9.1, especially in fine particles. The transformation potentials of individual OPE to its TP were size-dependent. These findings are significant to comprehending the fates of OPEs and TPs in urban atmosphere.
有机磷酸酯（OPEs）转化产物（TPs）的尺寸依赖性气粒分配以及OPEs在环境大气中向TPs的转化潜力仍未得到充分研究。为填补这一知识空白，我们分析了在中国北京、上海和广州在不同气象条件下采集的气态和按粒径分级的颗粒物样本。OPEs的浓度与世界其他主要城市相当，但TPs的水平低于这些城市。Li-Ma-Yang模型很好地预测了OPEs和TPs的按粒径分级的气粒分配系数（K），log K>9.1。纳入相对湿度的多元线性回归模型缩小了log K<9.1的OPEs预测K值与观测K值之间的差距，但仍低估了K值。因此，未来的气粒分配模型应考虑这些OPEs的湿度依赖性水膜吸附和转化，尤其是在细颗粒物中。九对OPE与TP浓度比的粒径分布并不统一。温度对TPs的气粒分配有负面影响，并抑制了颗粒相中磷酸三（2-氯丙基）酯（TCIPP）向磷酸双（1-氯-2-丙基）酯（BCIPP）以及磷酸三苯酯（TPhP）向4-羟基苯基二苯基磷酸酯（4-OH-DPHP）的转化。气态TPs对OPEs的人体吸入健康风险的贡献大于颗粒结合态TPs。这些发现对于理解城市环境中大气TPs的归宿具有重要意义。环境意义：有机磷酸酯（OPEs）的转化产物（TPs）相对于OPEs表现出相当甚至更高的毒性，但其大气行为仍未完全了解。在本研究中，在北京、上海和广州采集了气态和按粒径分级的颗粒物样本，以探索TPs的气粒分配行为及其从OPEs的转化潜力。结果表明，相对湿度影响log K<9.1的化合物的气粒分配行为，尤其是在细颗粒物中。单个OPE向其TP的转化潜力与粒径有关。这些发现对于理解城市大气中OPEs和TPs的归宿具有重要意义。
