In Situ Sampling Tool for Assessing Bioavailability and Toxicity of Sediments

摘要 该项目介绍了一种测定沉积物污染物生物利用度的新策略。 具有广泛的化学结构、性质和物理化学行为。该项目 满足超级基金利益相关者的迫切需求，以方便和可靠的方式确定 受污染沉积物造成的人类健康风险以及实施的补救战略的有效性。 原位采样/生物利用度测定(IS2B)工具是一种新的、正在申请专利的设备，能够 同时测定散装水和孔隙水中的污染物水平 方法检出限(MDLS)。当部署时，管状IS2B装置的一半被埋在沉积物中 另一种是暴露在散装水中。集成式多通道泵可同时抽取散装水和 泥沙孔隙水进入主动采样装置，并分别在高、低理想流量下推送 通过一系列过滤器和吸附介质。水样可以存储在设备中，也可以 随意排入散装水中。由于在部署期间不受限制地获取孔隙和散装水， IS2B工具为各种污染物提供超低MDL，范围从完全水溶性到 高度吸附和疏水性。此功能将设备与目前可用的无源设备区分开来 抽样策略。 以前的三个SRP项目的技术诀窍被用来测试IS2B的工作假设 技术可以可靠地(I)采样散装和孔隙水污染物，以供分析在亚ng/L范围内，(Ii) 通报沉积物污染物的生物有效性和生物活性；(3)通报人类暴露和 (4)跟踪底泥修复活动的进展情况。 实验室和实地研究将对来自阿波普卡湖的受污染沉积物进行，阿波普卡湖是 佛罗里达州的各种超级基金网站。为了说明IS2B应用的广度，本项目集中在 两种传统的和三种新出现的沉积物污染物(p，p‘-DDE，狄氏剂与氟虫腈，三氯生， 三氯卡班)。因为通过模型预测的生物积累量与 采样器数据和污染物的实际生物累积、生物有效性和生物累积将在#年进行评估。 通过人体测定对新添加和长期老化的污染沉积物进行实验室实验 两种受试生物的负荷量：杂色蚯蚓和Pimephales proelas。对生物的反应 还将使用DNA微阵列分析来测量鱼类体内的污染物暴露情况，以评估可能 不能仅仅根据母体化合物的身体负担来预测。它们之间的数学关系 散装水、孔隙水、蠕虫和鱼中的污染物浓度将根据理论和实验室数据进行计算， 并将其应用于IS2B衍生数据，以预测风险并跟踪两种补救方法的有效性， 颗粒活性碳(GAC)的改性和污染底泥的深耕。

ABSTRACT This project introduces a novel strategy for bioavailability determination of sediment-borne contaminants featuring a wide range of chemical structures, properties and physical-chemical behaviors. The project addresses the pressing need of Superfund stakeholders to determine in a convenient and reliable fashion both human health risks from contaminated sediments and the effectiveness of implemented remediation strategies. The in situ sampling/bioavailability determination (IS2B) tool is a novel, patent-pending device enabling simultaneous determination of contaminant levels in bulk water and pore water at hitherto unattainably low method detection limits (MDLs). When deployed, one half of the tubular IS2B device is buried in sediment and the other is exposed to bulk water. Integrated multi-channel pumps simultaneously draw bulk water and sediment pore water into the active sampling device and push it at, respectively, high and low desirable flow rates through an array of filters and adsorption media. Water samples either can be stored in the device or expelled into the bulk water at will. Due to unlimited access to pore and bulk water during deployment, the IS2B tool provides ultra-low MDLs for a broad spectrum of contaminants, ranging from fully water-soluble to highly sorptive and hydrophobic. This functionality distinguishes the device from presently available passive sampling strategies. Know-how from three previous SRP projects is being leveraged to test the working hypothesis that the IS2B technology can serve to reliably (i) sample bulk and pore water pollutants for analysis in the sub-ng/L range, (ii) inform on the bioavailability and bioactivity of sediment contaminants, (iii) inform on human exposures and associated health risks from fish consumption, and (iv) track the progress of sediment remediation activities. Laboratory and field studies will be conducted with contaminated sediments from Lake Apopka, home to one of Florida's various Superfund sites. To illustrate the breadth of IS2B applicability, this project concentrates on two traditional and three emerging sediment contaminants (p,p'-DDE, dieldrin versus fipronil, triclosan, triclocarban). Because there may be discrepancies between the bioaccumulation predicted via modeling from sampler data and actual bioaccumulation, bioavailability and bioaccumulation of pollutants will be assessed in lab experiments with freshly spiked and long-term aged contaminated sediments via determination of body burdens in two test organisms: Lumbriculus variegatus and Pimephales promelas. Biological responses to contaminant exposure will also be measured in fish using DNA microarray analysis to evaluate effects that may not be predicted solely based on body burden of parent compounds. Mathematical relationships between pollutant concentrations in bulk water, pore water, worms and fish will be formulated from theory and lab data, and applied to IS2B-derived data to predict risk and track the effectiveness of two remediation approaches, granular activated carbon (GAC) amendment and deep tilling of contaminated sediment.