Human exposure to per- and polyfluoroalkyl substances also known as PFAS is an ongoing occupational and environmental health problem. This study seeks to characterise multiple pathways for firefighters’ exposure to PFAS. PFAS were analysed in 688 environmental samples such as eggs, fruits, vegetables, dust, soil, surface swabs, appliance washes and water obtained from fire stations. Relevant exposure pathways were identified and daily intake levels were estimated using PFAS concentrations and exposure factors relevant to firefighters.

Five PFAS including perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), 6:2 fluorotelomer sulfonate (6:2 FTS), and 8:2 fluorotelomer sulfonic acid (8:2 FTS) were frequently detected in the samples. Based on the median concentrations in each sample type, PFOS was the most abundant contaminant in eggs (80%), fruits (52%), dust (81%), surface swab (66%), soil (83%) and appliance wash (31%) samples. On the other hand, PFHxS was most abundant in vegetables (77%) and 8:2 FTS in water (58%). The intake estimation results show that dietary exposure from ingestion of foods produced on fire stations was the predominant exposure pathway, representing 82% and 62% of firefighters’ total PFAS intake under typical and worst-case exposure scenarios, respectively. Incidental ingestion and dermal absorption of PFAS in dust contributed 15% for typical and 34% for worst-case exposure scenarios. The relative contributions from incidental ingestion and dermal absorption of PFAS in soil and appliance washes were insignificant. Overall, the study identifies multiple exposure pathways relevant to career firefighters including consumption of food grown on fire stations, which has not previously been recognised within the occupational exposure context. The results suggest exposure control strategies that target foods produced on fire stations could substantially reduce firefighters’ exposure to PFAS.

人类接触全氟烷基物质和多氟烷基物质（也称为 PFAS）是一个持续存在的职业和环境健康问题。本研究旨在描述消防员接触 PFAS 的多种途径。对 688 个环境样本中的 PFAS 进行了分析，这些样本包括从消防站获得的鸡蛋、水果、蔬菜、灰尘、土壤、表面拭子、器具清洗剂和水。确定了相关暴露途径，并使用 PFAS 浓度和与消防员相关的暴露因素估算了每日摄入水平。

全氟辛烷磺酸 (PFOS)、全氟辛酸 (PFOA)、全氟己烷磺酸 (PFHxS)、6:2 氟调聚物磺酸 (6:2 FTS) 和 8:2 氟调聚物磺酸 (8:2 FTS) 等五种 PFAS 经常被使用。样品中检测到。根据每种样本类型的中位浓度，PFOS 是鸡蛋 (80%)、水果 (52%)、灰尘 (81%)、表面拭子 (66%)、土壤 (83%) 和器具清洗液中含量最丰富的污染物(31%) 样本。另一方面，全氟己烷磺酸 (PFHxS) 在蔬菜中含量最高 (77%)，在水中含量最高 (58%)，比例为 8:2 FTS。摄入量估算结果表明，通过摄入消防站生产的食物而进行的膳食暴露是主要的暴露途径，在典型和最坏情况暴露情况下，分别占消防员 PFAS 总摄入量的 82% 和 62%。粉尘中 PFAS 的偶然摄入和皮肤吸收在典型暴露情况下占 15%，在最坏情况暴露情况下占 34%。土壤和器具洗涤液中 PFAS 的偶然摄入和皮肤吸收的相对贡献微不足道。总体而言，该研究确定了与职业消防员相关的多种暴露途径，包括食用消防站种植的食物，这在职业暴露背景下之前尚未得到认可。结果表明，针对消防站生产的食品的暴露控制策略可以大大减少消防员接触 PFAS 的情况。