Abstract Decamethylcyclopentasiloxane (D5) is frequently used in personal care products (PCPs). In the gas phase, D5 is oxidized to form 1-hydroxynonamethylcyclopentasiloxane (D4TOH), which can partition to the particle phase. Numerous studies have reported secondary organic aerosol (SOA) formation via hydroxyl (OH) radical-initiated oxidation of D5. It is expected that PCPs have a significant impact on SOA, but the extent has not yet been investigated. To date, no studies have reported the occurrence of PCP-derived SOA in ambient particulate matter. This study examined fine particulate matter (PM2.5) collected in Atlanta, GA and Houston, TX and determined D4TOH was present in 28 of 29 and 33 of 46 ambient PM2.5 samples, respectively. Gas chromatographic retention data in the form of the Kovats index is reported for the first time to aid others in identifying this compound in order to assess the impact of PCPs on SOA formation. The estimated concentration of D4TOH ranged from 16 to 185 pg m-3 in Atlanta and 19–206 pg m-3 in Houston. Synthetic musks were also detected in Atlanta and Houston PM2.5 samples, which is consistent with PCPs impacting urban air quality. Because of its’ specificity and demonstrated detectability, D4TOH may be useful as a tracer of PCP-derived secondary organic aerosol.

中文翻译：

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检测来自个人护理产品的二次有机气溶胶示踪剂

摘要 十甲基环戊硅氧烷 (D5) 经常用于个人护理产品 (PCP)。在气相中，D5 被氧化形成 1-羟基九甲基环戊硅氧烷 (D4TOH)，它可以分配到颗粒相中。许多研究报告了通过羟基 (OH) 自由基引发的 D5 氧化形成二次有机气溶胶 (SOA)。预计 PCP 会对 SOA 产生重大影响，但其影响程度尚未调查。迄今为止，尚无研究报告环境颗粒物中出现 PCP 衍生的 SOA。该研究检查了在佐治亚州亚特兰大和德克萨斯州休斯顿收集的细颗粒物 (PM2.5)，并确定 D4TOH 分别存在于 29 个和 46 个环境 PM2.5 样品中的 33 个中。首次报告了 Kovats 指数形式的气相色谱保留数据，以帮助其他人识别该化合物，从而评估 PCP 对 SOA 形成的影响。D4TOH 的估计浓度在亚特兰大为 16 至 185 pg m-3，在休斯顿为 19-206 pg m-3。在亚特兰大和休斯顿 PM2.5 样本中也检测到合成麝香，这与影响城市空气质量的 PCP 一致。由于其特异性和已证明的可检测性，D4TOH 可用作 PCP 衍生的二次有机气溶胶的示踪剂。这与影响城市空气质量的 PCP 一致。由于其特异性和已证明的可检测性，D4TOH 可用作 PCP 衍生的二次有机气溶胶的示踪剂。这与影响城市空气质量的 PCP 一致。由于其特异性和已证明的可检测性，D4TOH 可用作 PCP 衍生的二次有机气溶胶的示踪剂。