Transformation of organophosphate esters (OPEs) in natural ambient air and potential health risks from coexposure to OPEs and their transformation products are largely unclear. Therefore, a novel framework combining field-based investigation, in silico prediction, and target and suspect screening was employed to understand atmospheric persistence and health impacts of OPEs. Alkyl-OPE transformation products ubiquitously occurred in urban ambient air. The transformation ratios of tris(2-butoxyethyl) phosphate were size-dependent, implying that transformation processes may be affected by particle size. Transformation products of chlorinated- and aryl-OPEs were not detected in atmospheric particles, and atmospheric dry deposition might significantly contribute to their removal. Although inhalation risk of coexposure to OPEs and transformation products in urban ambient air was low, health risks related to OPEs may be underestimated as constrained by the identification of plausible transformation products and their toxicity testing in vitro or in vivo at current stage. The present study highlights the significant impact of particle size on the atmospheric persistence of OPEs and suggests that health risk assessments should be conducted with concurrent consideration of both parental compounds and transformation products of OPEs, in view of the nonnegligible abundances of transformation products in the air and their potential toxicity in silico.

中文翻译：

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深入了解城市环境空气中有机磷酸酯的大气持久性、转化和健康影响

自然环境空气中有机磷酸酯 (OPE) 的转化以及共同暴露于 OPE 及其转化产物的潜在健康风险在很大程度上尚不清楚。因此，一个新的框架结合了基于现场的调查，在 silico预测、目标和嫌疑人筛选被用来了解 OPE 的大气持久性和健康影响。烷基-OPE 转化产物普遍存在于城市环境空气中。三(2-丁氧基乙基) 磷酸盐的转化率与尺寸有关，这意味着转化过程可能受颗粒尺寸的影响。在大气颗粒中未检测到氯化和芳基 OPE 的转化产物，大气干沉降可能显着有助于它们的去除。尽管在城市环境空气中同时暴露于 OPE 和转化产物的吸入风险很低，但与 OPE 相关的健康风险可能会被低估，因为对合理的转化产物的识别及其体外或毒性试验的限制活体现阶段。本研究强调了颗粒大小对 OPE 的大气持久性的显着影响，并建议健康风险评估应同时考虑 OPE 的母体化合物和转化产物，因为空气中转化产物的丰度不可忽略。及其在计算机中的潜在毒性。