Department of Chemical, Biochemical, and Environmental Engineering, University of Maryland, Baltimore, Maryland, USA.
Exponent, Alexandria, Virginia, USA.
Environ Toxicol Chem. 2018 Sep;37(9):2496-2505. doi: 10.1002/etc.4186. Epub 2018 Aug 6.
In situ amendment of sediments with highly sorbent materials like activated carbon (AC) is an increasingly viable strategy to reduce the bioavailability of persistent, sediment-associated contaminants to benthic communities. Because in situ sediment remediation is an emerging strategy, much remains to be learned about the field conditions under which amendments can be effective, the resilience of amendment materials toward extreme weather conditions, and the optimal design of engineered applications. We report the results of a multiyear, pilot-scale field investigation designed to measure the persistence and efficacy of AC amendments to reduce the bioavailability of polychlorinated biphenyls (PCBs) in an intertidal Phragmites marsh. The amendments tested were granular AC (GAC), GAC with a layer of sand, and a pelletized fine AC. Key metrics presented include vertically resolved black carbon concentrations in sediment and PCB concentrations in sediment, porewater, and several invertebrate species. The results demonstrate that all 3 amendments withstood Hurricane Sandy and remained in place for the duration of the study, successfully reducing porewater PCB concentrations by 34 to 97%. Reductions in invertebrate bioaccumulation were observed in all amendment scenarios, with pelletized fine AC producing the most pronounced effect. The present findings support the use of engineered AC amendments in intertidal marshes and can be used to inform amendment design, delivery, and monitoring at other contaminated sediment sites. Environ Toxicol Chem 2018;37:2496-2505. © 2018 SETAC.
原位用高吸附性材料（如活性炭）改良沉积物是一种减少持久性、与沉积物有关的污染物对底栖生物群落生物可利用性的可行策略。由于原位沉积物修复是一种新兴策略，人们仍然需要了解在哪些现场条件下改良剂可以有效，改良材料对极端天气条件的恢复能力，以及工程应用的最佳设计。我们报告了一项多年的试点规模现场调查的结果，该调查旨在测量活性炭改良剂对减少潮间带芦苇沼泽中多氯联苯（PCBs）生物可利用性的持久性和效果。测试的改良剂是颗粒活性炭（GAC）、GAC 加一层砂和颗粒状细活性炭。提出的关键指标包括沉积物中垂直分辨率的黑碳浓度和沉积物、孔隙水和几种无脊椎动物物种中的 PCB 浓度。结果表明，所有 3 种改良剂都经受住了桑迪飓风的考验，并在研究期间保持原位，成功地将孔隙水中的 PCB 浓度降低了 34%至 97%。在所有改良剂情况下都观察到无脊椎动物生物积累的减少，颗粒状细活性炭产生的效果最明显。目前的研究结果支持在潮间带沼泽中使用工程化的活性炭改良剂，并可用于为其他受污染沉积物地点的改良剂设计、交付和监测提供信息。环境毒理化学 2018;37:2496-2505。©2018 SETAC。
