Center for Fisheries, Aquaculture and Aquatic Sciences, School of Biological Sciences, Southern Illinois University, Carbondale, IL, 62901, USA.
Department of Environmental Science and Policy, University of California Davis, Davis, CA, 95616, USA.
Environ Pollut. 2024 Nov 1;360:124606. doi: 10.1016/j.envpol.2024.124606. Epub 2024 Jul 23.
The Sacramento Deep Water Ship Channel (SDWSC) in the San Francisco Estuary, which is an active commercial port, is critical habitat for pelagic fish species including delta smelt (Hypomesus transpacificus), longfin smelt (Spirinchus thaleichthys), and Sacramento perch (Archoplites interruptus). Pelagic organism decline has been attributed to covarying factors such as manipulation of habitat, introduction of invasive species, decrease in food production, and contaminant exposure. Quantification of bioavailable toxicant loads in the SDWSC is limited despite previous surveys that have detected elevated contaminant concentrations in the sediments. Therefore, the focus of the present study was to characterize the bioavailability of the contaminants in the SDWSC from six sites along the channel. At each site, organochlorine pesticides (OCPs), pyrethroid insecticides, polyaromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) were quantified in sediment, zooplankton, and suspended solids. In addition, Tenax extraction was used to measure the bioaccessible fraction of sediment-associated contaminants freely dissolved in the water. Bioaccessible contaminants in the sediment provided an uptake route for these stressors into invertebrates and fish with bioaccessible OCPs being found at all sites, particularly 4,4'-dichlorodiphenyldichloroethylene (DDE). Bifenthrin was the only pyrethroid detected in the chosen matrices and it was found at concentrations below levels of concern. Bioaccessible PAHs were found at all sites, with highest detections for phenanthrene and pyrene. No PCBs were detected in sediments, but were detected in both suspended solids and zooplankton. Contaminant concentrations overall were significantly higher in suspended solids, followed by zooplankton and sediments. The highest sediment concentrations of DDE, fluoranthene, pyrene, and dibenzo[a,h]anthracene exceeded sediment quality benchmarks indicating potential risk to sediment-dwelling species. Finally, elevated contaminant levels were found in both suspended solids and zooplankton, suggesting additional risk to pelagic species in the SDWSC.
萨克拉门托深水区航道（SDWSC）位于旧金山湾，是一个活跃的商业港口，是包括亚洲羊头濑鱼（Hypomesus transpacificus）、长鳍羊头濑鱼（Spirinchus thaleichthys）和萨克拉门托鲈（Archoplites interruptus）等洄游鱼类的关键栖息地。洄游鱼类的减少归因于栖息地的人为改变、入侵物种的引入、食物产量下降和污染物暴露等多种因素。尽管先前的调查已经在沉积物中检测到了升高的污染物浓度，但对 SDWSC 中生物可利用的有毒物质负荷的量化仍然有限。因此，本研究的重点是从航道的六个地点描述 SDWSC 中污染物的生物可利用性。在每个地点，都对沉积物、浮游动物和悬浮固体中的有机氯农药（OCPs）、拟除虫菊酯类杀虫剂、多环芳烃（PAHs）和多氯联苯（PCBs）进行了量化。此外，还用 Tenax 萃取法测量了自由溶解在水中的与沉积物相关的污染物的生物可利用部分。沉积物中具有生物可利用性的污染物为这些压力源进入无脊椎动物和鱼类提供了一条吸收途径，所有地点都发现了具有生物可利用性的 OCPs，特别是 4,4'-二氯二苯二氯乙烯（DDE）。在所选基质中仅检测到了联苯菊酯，其浓度低于关注水平。所有地点都检测到了具有生物可利用性的 PAHs，其中最高的检测到的是菲和芘。在沉积物中没有检测到 PCBs，但在悬浮固体和浮游动物中都有检测到。总的来说，污染物浓度在悬浮固体中最高，其次是浮游动物和沉积物。DDE、荧蒽、芘和二苯并[a,h]蒽的沉积物浓度最高，超过了沉积物质量基准，表明对栖息在沉积物中的物种存在潜在风险。最后，在悬浮固体和浮游动物中都发现了升高的污染物水平，这表明 SDWSC 中的洄游鱼类也面临着额外的风险。
