Abstract

Background:

In human biomonitoring, blood is often used as a matrix to measure exposure to per- and polyfluoroalkyl substances (PFAS). Because the toxicokinetics of a substance (determining the steady-state blood concentration) may affect the toxic potency, the difference in toxicokinetics among PFAS has to be accounted for when blood concentrations are used in mixture risk assessment.

Objectives:

This research focuses on deriving relative potency factors (RPFs) at the blood serum level. These RPFs can be applied to PFAS concentrations in human blood, thereby facilitating mixture risk assessment with primary input from human biomonitoring studies.

Methods:

Toxicokinetic models are generated for 10 PFAS to estimate the internal exposure in the male rat at the blood serum level over time. By applying dose–response modeling, these internal exposures are used to derive quantitative internal RPFs based on liver effects.

Results:

Internal RPFs were successfully obtained for nine PFAS. Perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), perfluorononanoic acid (PFNA), perfluorododecanoic acid (PFDoDA), perfluorooctane sulfonic acid (PFOS), and hexafluoropropylene oxide-dimer acid (HFPO-DA, or GenX) were found to be more potent than perfluorooctanoic acid (PFOA) at the blood serum level in terms of relative liver weight increase, whereas perfluorobutane sulfonic acid (PFBS) and perfluorohexane sulfonic acid (PFHxS) were found to be less potent. The practical implementation of these internal RPFs is illustrated using the National Health and Nutrition Examination Survey (NHANES) biomonitoring data of 2017–2018.

Discussion:

It is recommended to assess the health risk resulting from exposure to PFAS as combined, aggregate exposure to the extent feasible. https://doi.org/10.1289/EHP10009

中文翻译：

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人体生物监测中全氟烷基物质和多氟烷基物质 (PFAS) 混合物风险评估的内部相对效力因素

摘要

背景：

在人体生物监测中，血液通常用作基质来测量全氟烷基物质和多氟烷基物质 (PFAS) 的暴露量。由于物质的毒代动力学（确定稳态血液浓度）可能会影响毒性效力，因此在混合物风险评估中使用血液浓度时，必须考虑 PFAS 之间毒代动力学的差异。

目标：

本研究的重点是推导血清水平的相对效力因子（RPF）。这些 RPF 可应用于人类血液中的 PFAS 浓度，从而促进利用人类生物监测研究的主要输入进行混合物风险评估。

方法：

生成 10 种 PFAS 的毒代动力学模型，以估计雄性大鼠血清水平随时间的内暴露情况。通过应用剂量反应模型，这些内部暴露用于根据肝脏影响得出定量的内部 RPF。

结果：

已成功获得 9 种 PFAS 的内部 RPF。全氟丁酸 (PFBA)、全氟己酸 (PFHxA)、全氟壬酸 (PFNA)、全氟十二烷酸 (PFDoDA)、全氟辛烷磺酸 (PFOS) 和六氟环氧丙烷二聚酸 (HFPO-DA，或 GenX)就相对肝脏重量增加而言，血清水平上的全氟辛酸（PFOA）比全氟辛酸（PFOA）有效，而全氟丁磺酸（PFBS）和全氟己烷磺酸（PFHxS）的效力较弱。使用 2017-2018 年国家健康和营养检查调查 (NHANES) 生物监测数据说明了这些内部 RPF 的实际实施。

讨论：

建议在可行的范围内评估因接触 PFAS 造成的健康风险。https://doi.org/10.1289/EHP10009