North Carolina Cooperative Fish and Wildlife Research Unit, Department of Applied Ecology, North Carolina State University, Raleigh, North Carolina 27695, United States.
Department of Applied Ecology, North Carolina State University, Raleigh, North Carolina 27695, United States.
Environ Sci Technol. 2020 Jun 2;54(11):6800-6811. doi: 10.1021/acs.est.9b05007. Epub 2020 May 12.
Per- and polyfluoroalkyl substances (PFASs) have attracted scientific and regulatory attention due to their persistence, bioaccumulative potential, toxicity, and global distribution. We determined the accumulation and trophic transfer of 14 PFASs (5 short-chain and 9 long-chain) within the food web of the Yadkin-Pee Dee River of North Carolina and South Carolina, US. Food web components and pathways were determined by stable isotope analyses of producers, consumers, and organic matter. Analyses of water, sediment, organic matter, and aquatic biota revealed that PFASs were prevalent in all food web compartments. Biofilm, an aggregation of bacteria, fungi, algae, and protozoans and a basal resource for the aquatic food web, showed high PFAS accumulation (in 10 of 14 compounds), particularly for perfluorooctanoic acid, with the greatest mean concentration of 463.73 ng/g. The food web compartment with the most detections and greatest concentrations of PFASs was aquatic insects; all 14 PFASs were detected in individual aquatic insect samples (range of <limit of detection [<LOD] to 1670.10 ng/g of wet weight [WW]). These findings may suggest a trophic link between biofilm PFASs and aquatic insect PFASs. Individual fish tissue samples ranged from <LOD to 797.00 ng/g of WW, where perfluorooctanesulfonate (PFOS) was the dominant PFAS among all samples (64%). The ova of an imperiled fish, the robust redhorse (), had concentrations of 10 PFASs (range of <LOD to 482.88 ng/g of WW) and the highest PFOS concentration (482.88 ng/g of WW), indicating a likely maternal transfer. The trophic magnification factors (TMFs) calculated in this study showed that various taxa accumulated PFAS compounds differently. PFBS, a short-chain PFAS compound that would presumably exhibit lesser TMFs, had nine values among our compartments and organisms >1.0 (range of 0.57 to 2.33); it is possible that an unmeasured PFBS precursor may be accumulating in biota and metabolizing to PFBS, leading to a higher than expected TMFs for this compound. Our findings demonstrate the prevalence of PFASs in a freshwater food web with potential implications for ecological and human health.
全氟和多氟烷基物质（PFAS）因其持久性、生物蓄积潜力、毒性和全球分布而引起了科学界和监管机构的关注。我们确定了美国北卡罗来纳州和南卡罗来纳州的雅德金-皮迪河的食物网中 14 种 PFAS（5 种短链和 9 种长链）的积累和营养转移。通过对生产者、消费者和有机质进行稳定同位素分析，确定了食物网成分和途径。对水、沉积物、有机质和水生生物群的分析表明，PFAS 普遍存在于所有食物网隔室中。生物膜是细菌、真菌、藻类和原生动物的聚集物，也是水生食物网的基础资源，它显示出高 PFAS 积累（在 14 种化合物中的 10 种中），特别是全氟辛酸，其平均浓度最高为 463.73ng/g。PFAS 检测最多、浓度最高的食物网隔室是水生昆虫；所有 14 种 PFAS 都在单个水生昆虫样本中被检测到（范围为<检测限 [LOD] 至 1670.10ng/g 湿重 [WW]）。这些发现可能表明生物膜 PFAS 与水生昆虫 PFAS 之间存在营养联系。个别鱼类组织样本的浓度范围为<LOD 至 797.00ng/g WW，其中全氟辛烷磺酸（PFOS）是所有样本中含量最高的 PFAS（64%）。一种濒危鱼类，强壮的红鲷鱼（）的卵中含有 10 种 PFAS（范围为<LOD 至 482.88ng/g WW），且 PFOS 浓度最高（482.88ng/g WW），表明可能存在母体转移。本研究中计算的营养级放大因子（TMF）表明，不同分类群对 PFAS 化合物的积累方式不同。短链 PFAS 化合物 PFBS 的 TMF 值预计会较低，但在我们的隔室和生物组织中，有九个值大于 1.0（范围为 0.57 至 2.33）；可能存在一种未测量的 PFBS 前体正在生物体内积累并代谢为 PFBS，从而导致该化合物的 TMF 高于预期。我们的研究结果表明，PFAS 在淡水食物网中普遍存在，这可能对生态和人类健康产生影响。
