Shi Yanfeng, Han Xinle, Wu Lixingzi, Fu Ling, Xue Weina, Jing Xuli, Xu Jing, Zhang Zhibin, Ding Botao
School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, China.
School of Water Conservancy and Environment, University of Jinan, Ji´Nan, China.
Environ Geochem Health. 2025 Jun 14;47(7):268. doi: 10.1007/s10653-025-02532-7.
Hexafluoropropylene oxide dimer acid (HFPO-DA, tradename Gen-X) is used as a substitute to perfluorooctanoic acid (PFOA). Its widespread presence in the environment and potential health risks on humans. Nevertheless, the research on transport of HFPO-DA in saturated porous media remains limited. This study investigates the effects of hydrochemical conditions on the transport behavior of HFPO-DA and PFOA in quartz sand and limestone porous media, such as ionic type (Na, Ca), ionic strength (1 mM, 10 mM, 50 mM) and initial solution pH (pH = 4, 7, 10). Findings indicate that both HFPO-DA and PFOA have high mobility in saturated media. The transport of HFPO-DA through quartz sand and limestone porous media is not notably influenced by different ionic types and strengths, with recoveries all over 98.94% and R all below 1.02. Similarly, PFOA showed high mobility under different ionic conditions, with recoveries exceeding 101.68% and Rf less than 1.02.The influence of initial pH on the transport of HFPO-DA showed that HFPO-DA is pH-sensitive in quartz sand, with retention enhanced and significant trailing of the BTC at pH = 4; however, the pH-buffering capacity of limestone media reduced the impact of pH on HFPO-DA transportation. Compared with PFOA, HFPO-DA transported faster at pH = 4 with an R value of 0.97, lower than that of PFOA at 1.21, due to its smaller molecular weight and shorter carbon chain. Overall, the research reveals the potent mobility of HFPO-DA and PFOA in the environment, highlighting their groundwater pollution potential and environmental risks.
六氟环氧丙烷二聚酸（HFPO-DA，商品名Gen-X）被用作全氟辛酸（PFOA）的替代品。它在环境中广泛存在并对人类具有潜在健康风险。然而，关于HFPO-DA在饱和多孔介质中迁移的研究仍然有限。本研究调查了水化学条件对HFPO-DA和PFOA在石英砂和石灰石多孔介质中迁移行为的影响，如离子类型（Na、Ca）、离子强度（1 mM、10 mM、50 mM）和初始溶液pH值（pH = 4、7、10）。研究结果表明，HFPO-DA和PFOA在饱和介质中都具有较高的迁移率。HFPO-DA通过石英砂和石灰石多孔介质的迁移不受不同离子类型和强度的显著影响，回收率均超过98.94%，R值均低于1.02。同样，PFOA在不同离子条件下也表现出较高的迁移率，回收率超过101.68%，Rf小于1.02。初始pH值对HFPO-DA迁移的影响表明，HFPO-DA在石英砂中对pH敏感，在pH = 4时保留增强且BTC出现明显拖尾；然而，石灰石介质的pH缓冲能力降低了pH对HFPO-DA迁移的影响。与PFOA相比，HFPO-DA在pH = 4时迁移更快，R值为0.97，低于PFOA的1.21，这是由于其分子量较小且碳链较短。总体而言，该研究揭示了HFPO-DA和PFOA在环境中的强大迁移能力，突出了它们对地下水污染的潜在可能性和环境风险。
