Concentration of trace metals from mine-derived pollution in marine waters and sediments across the Torres Strait (TS), October 2016 (NESP TWQ 2.2.2, CSIRO)

This dataset summarises the results of a survey to determine the concentration of trace metals from mine-derived pollution in marine waters and sediments across the Torres Strait during October 2016. Sampling was performed by a CSIRO team between 3 and 16 October 2016 on board the MV Eclipse. Surface water samples were collected from 21 sites using strict sampling protocols that are designed to minimise contamination (USEPA, 1996; Angel et al., 2010b).

METHODS:

- Sample Collection
Clean powder-free vinyl gloves were worn for the handling of all sample bottles and sampling equipment, and the collection of water samples before sediment samples at any given site. Acid washed sampling bottles (0.5, 1, and 5 L), double-bagged in zip-lock bags and stored inside an esky containing ice bricks was transported on the tender to each site. The 0.5 L bottle was used to collect a sample for total mercury analysis. The 1 L bottle was used for collecting a sample for total recoverable metals analyses other than mercury, and the 5 L bottle was used for collecting a sample for filterable (dissolved) and TSS-bound metals analyses other than mercury. At every sampling site a ‘clean hands’, ‘dirty hands’ protocol was used for taking water samples. This involved the ‘clean hands’ person opening the esky, placing gloves on hands, withdrawing the 1 L sample bottle from pre-labelled zip-lock bags, placing it into an attachment on a purpose built Perspex pole sampler, uncapping the bottle and holding onto the cap. The ‘dirty hands’ person then rapidly submerged the bottle in the pole sampler to a depth of approximately 50 cm to take the sample. Each sample bottle was rinsed twice with water from the sample site by filling each bottle, capping, shaking and emptying. The 1 L bottle was used to collect water samples that were decanted into the 0.5 and 5 L bottles until they were full of sample, after which the 1 L bottle was filled a final time. The ‘clean hands’ person capped each bottle once they well filled and replaced them into the zip-lock bags in the esky. The water samples were placed into a fridge on board the MV Eclipse prior to filtration. The samples were filtered within 6 hours of sample collection.

For quality control purposes, field blanks were collected at sites M, O and 8 and duplicate samples were collected at sites N, O and A. Field blanks for trace metals analysis were prepared at the designated sites by opening a 1 L bottle to the air for approximately 30 seconds followed by capping and returning to its zip-lock bag. On return to the MV Eclipse, the bottle was then filled with 1 L of deionised water.

Salinity and pH were measured using an Orion Star A329 portable meter (Thermo Scientific). Sample pH was measured using a Thermo Scientific Orion Gel-Filled ROSS pH Ultra Triode Electrode (8107UWMMD) that was calibrated using pH 4.00, 7.00 and 10.00 buffers. Salinity was measured using a Thermo Scientific Orion Conductivity Cell (013010MD) that was calibrated using KCl conductivity standards.

Sediment samples were collected from each site immediately after the water sampling. A combination of techniques were employed to collect the sediment samples that depended on the local water current conditions and ability of the corer to penetrate the sediment. Firstly, a gravity core sampler was deployed from the Eclipse, which collected up to 12 cm deep sediment within pre-loaded plastic core tubes. If this was unsuccessful divers took hand cores of up to 7 cm depth by diving to the sea bed. The core tubes were capped with plastic stoppers and wherever possible, returned to the surface in an upright position. If the substrate was too hard for hand coring, the divers took a grab of loose sediment samples by hand inside 250 mL polycarbonate vials.

The core tubes were withdrawn from the corer on-board the MV Eclipse, placed into zip-lock bags, and placed inside a freezer until frozen. The cores were then sectioned by allowing a core to partially thaw so that the sediment core could be extruded with a plastic plunger, before cutting into sections (typically 1-2 cm length) with a plastic blade. The core sections were placed into zip-lock bags and stored frozen for transport to the Lucas Heights laboratories. The contents of some of the shorter unconsolidated sediment cores became mixed, in which case the entire core was treated as a single sample rather than sub-sectioning. Triplicate cores/sediment grabs were generally taken at each site in order to assess sampling heterogeneity.

- Water sample processing
Water samples for analysis of trace metals were vacuum filtered through acid-washed 0.45 µm Millipore membrane filters using an acid washed polycarbonate filtration apparatus (Sartorius). The filtration assemblies were further cleaned before processing each sample by first filtering a 100 mL volume of 10% v/v nitric acid solution followed by two 150 mL volumes of deionised water, and finally, a 50 mL volume of sample. For each volume of these solutions the filtration rig was held on an angle and rotated both before and after filtration so that the solutions came into contact with all surfaces of the top and bottom compartments of the apparatus to ensure rigorous rinsing / pre-treatment was achieved. The 50 mL aliquot of sample used to pre-clean the filtration rig was poured into the 1 L acid washed Nalgene filtrate receiving bottle, shaken to pre-treat the bottle, and discarded to waste. The sample was then filtered and the filtrate transferred into the receiving bottle. Between 4-6 L of each sample filtrate was retained for analysis. Filtrates were then preserved by addition of 2 mL/L of concentrated nitric acid (Merck Tracepur).

For the field blanks, approximately half of the 1L sample was filtered and preserved. The remaining 500 mL was acidified and retained for subsequent analysis. The difference between the filtered and unfiltered field blanks gave an indication if filtration resulted in contamination.

Suspended sediment samples for total suspended sediment (TSS) and TSS-bound metals analyses were acquired by filtering known volumes of water through pre-weighed 0.45 µm membrane filters (Millipore). The filters were rinsed with 10% nitric acid before use and each sample was filtered using the filtration procedure described above. After the sample was filtered and the filtrate removed, the upper compartment of the filtration apparatus and the filter were rinsed with approximately 20 mL of deionised water to remove any salt. The filters were placed into acid-washed plastic Petri slides and stored frozen. The filters were transferred to the CSIRO Lucas Heights laboratories, after which they were oven-dried at 60oC, cooled to room temperature in a desiccator, and weighed. This procedure was repeated three times to ensure the mass was consistent, after which, the filters were stored at room temperature until total recoverable (TR) metals analysis was performed. The TSS concentration (mg/L) of the water samples was calculated using the difference in the mass of the filter before and after filtration divided by the volume of sample filtered.

- Analysis of dissolved metals
Dissolved Cd, Co, Cu, Ni, Pb and Zn in filtered samples were analysed by complexation and solvent extraction prior followed by quantitation of the pre-concentrated metals by ICPMS. The extraction procedure allowed the pre-concentration of metals by a factor of 25, thus allowing more accurate quantification. A dithiocarbamate complexation/solvent extraction method based on the procedure described by Magnusson and Westerlund (1981) was employed. The major differences were the use of a combined sodium bicarbonate buffer/ammonium pyrrolidine dithiocarbamate reagent (Apte and Gunn, 1987) and 1,1,1-trichloroethane as the extraction solvent in place of Freon. In brief, sample aliquots (250 mL) were buffered to pH 5 by the addition of the combined reagent and extracted into two 10-mL portions of triple-distilled trichloroethane. The extracts were combined and the metals back-extracted into 1 mL of concentrated nitric acid (Merck Tracepur). The back extracts were diluted to a final volume of 10 mL by addition of deionised water and analysed by inductively coupled plasma-mass spectrometry (ICPMS) (Agilent, 7500CE) using the instrument operating conditions recommended by the manufacturer. For quality control purposes a portion of the certified reference seawater NASS-6 (National Research Council (NRC), Canada) CRM was analysed in every sample batch.

Dissolved aluminium and iron concentrations were measured directly on portions of acidified filtered waters by ICP-AES (Varian730 ES) using matrix-matched standards. The concentrations of dissolved chromium were measured directly by ICP-MS (Agilent 7500CE ) following three-fold dilution with deionised water and calibration against matrix-matched standards.

The concentration of dissolved arsenic in the filtered samples was measured by hydride generation atomic absorption spectrometry (HG-AAS), using procedures based on the standard methods described by APHA (1998). Samples were first digested by addition of potassium persulfate (1% m/v final concentration) and heating to 120°C for 30 min in an autoclave. Hydrochloric acid, (3 M final concentration) was then added to the samples. Pentavalent arsenic was then pre-reduced to arsenic (III) by addition of potassium iodide (1% (m/v) final concentration) and ascorbic acid (0.2% (m/v) final concentration) and left standing for at least 30 min at room temperature prior to analysis. Arsenic concentrations were then measured by HG-AAS using a Varian VGA system operated under standard conditions recommended by the manufacturer. Arsenic (III) in solution was reduced to arsine by reduction with sodium borohydride, which was stripped from solution with argon gas into a silica tube, electrically heated at 925°C. Heating converted arsine into arsenic vapour, which was quantified by atomic absorption spectrometry.

For quality control purposes a portion of the certified reference seawater NASS-6 (National Research Council (NRC), Canada) CRM was analysed in every sample batch.

DOC was measured on aliquots of filtered samples collected during the June 2018 survey using a Shimadzu TOC-LCSH Total Organic Carbon Analyser using the procedures recommended by the manufacturer.

- Analysis of metals bound to total suspended solids (TSS) and benthic sediment
The TSS and benthic sediment was digested in pre-cleaned Teflon digestion vessels using aqua-regia digestions in a microwave-assisted reaction system (MARS). The membrane filters containing the suspended sediments or known quantities of dry benthic sediment were transferred into the MARS digestion vessels and subjected to pressurised digestion. The method involved adding 2.5 mL of concentrated nitric acid (Tracepur, Merck) and 7.5 mL of concentrated hydrochloric acid (Tracepur, Merck) to each digestion vessel and heating at high pressure in a MARS digestion system for 90 minutes. Once cool, the digest vessels were vented followed by dilution of the digest to a final volume of 40 mL using deionised water. The masses of the empty vessel, the vessel plus sample, and the vessel plus sample and acid mixture before and after heating were recorded to allow calculation of a dilution factor used in the determination of metal concentrations in the initial undiluted sample. For quality control purposes, portions of the certified reference sediments ERM-CC018 (IRMM) and PACS-3 (NRC Canada) were analysed in each sample batch.

Format:

This dataset consists of multiple Comma Separated Value (CSV) tables containing the data provided by the project team.

Data Location:

This dataset is filed in the eAtlas enduring data repository at: data\NESP-TWQ-2\2.2.2_TS-mine-pollution

本数据集汇总了2016年10月托雷斯海峡海域海水与沉积物中矿山源污染痕量金属浓度调查的结果。2016年10月3日至16日，澳大利亚联邦科学与工业研究组织(CSIRO)团队在MV Eclipse号科考船上完成了采样工作。研究人员依照严格的污染控制采样规程，在21个站位采集了表层海水样品（USEPA, 1996; Angel et al., 2010b）。

## 研究方法
### 样品采集
所有样品瓶与采样设备的操作，以及在任意站位先采集水样再采集沉积物样的过程，均需佩戴无粉聚乙烯手套。酸洗后的采样瓶（0.5 L、1 L及5 L）装入自封袋双层封装，置于装有冰砖的保温箱内，通过交通艇运至各采样站位。其中0.5 L瓶用于采集总汞分析样品，1 L瓶用于采集除汞外的总可回收金属分析样品，5 L瓶用于采集除汞外的可过滤态（溶解态）及总悬浮颗粒物(TSS)结合态金属分析样品。

每个采样站位均采用“净手-脏手”规程采集水样：由“净手”人员打开保温箱、佩戴手套、从预标记的自封袋中取出1 L采样瓶并安装至定制亚克力杆采样器的夹具上，拧下瓶盖并握持；随后由“脏手”人员快速将采样瓶浸入水下约50 cm深度完成采样。每个采样瓶需用站位处的海水冲洗两次：注满海水、加盖摇匀后倒空。先用1 L采样瓶采集水样，再将水样分装至0.5 L和5 L瓶至满，最后再次装满1 L采样瓶。“净手”人员在样品瓶注满后加盖，并放回保温箱内的自封袋中。水样在MV Eclipse号船上放入冰箱冷藏，需在采样后6小时内完成过滤。

为保障质量控制，在站位M、O和8采集了现场空白样，在站位N、O和A采集了平行样。痕量金属分析的现场空白样制备流程为：在指定站位打开1 L采样瓶暴露于空气中约30秒，加盖后放回自封袋；返回MV Eclipse号后，向瓶内注入1 L去离子水。

使用Orion Star A329型便携式分析仪（赛默飞世尔科技）测定盐度与pH值：pH值测定采用赛默飞世尔科技填充式ROSS pH超极三电极（8107UWMMD），使用pH 4.00、7.00及10.00缓冲液校准；盐度测定采用赛默飞世尔科技电导池（013010MD），使用氯化钾电导标准液校准。

沉积物样品在水样采集完成后立即在各站位采集。根据当地海流条件及采泥器穿透沉积物的能力，采用组合技术采集沉积物样：首先使用重力柱状采样器从Eclipse号下放，在预装的塑料柱状管中采集深度可达12 cm的沉积物柱样；若该操作失败，则由潜水员潜入海底采集深度可达7 cm的手采柱状样。柱状管使用塑料塞密封，尽可能保持直立状态运回水面；若底质过硬无法进行手采柱状采样，则由潜水员使用250 mL聚碳酸酯小瓶徒手抓取松散沉积物样品。

沉积物柱状管在MV Eclipse号船上从采泥器中取出后，装入自封袋并放入冷冻柜冷冻保存。随后将柱样部分解冻，使用塑料推杆将沉积物柱挤出，再用塑料刀片切成约1~2 cm的小段；将切段后的沉积物样品装入自封袋，冷冻保存并转运至卢卡斯高地实验室。部分较短的松散沉积物柱样出现混合，此类样品将整体作为单一样品处理，不再分切。为评估采样异质性，每个站位通常采集三份平行柱状样或沉积物抓取样。

### 水样处理
痕量金属分析用水样通过酸洗后的聚碳酸酯过滤装置（赛多利斯），经0.45 μm密理博微孔滤膜真空过滤。每批次样品过滤前，需先过滤100 mL 10%（体积分数）硝酸溶液、150 mL去离子水两次，再过滤50 mL待测样品以清洁过滤装置：每次过滤前后均将过滤装置倾斜并旋转，使溶液接触装置上下腔的所有表面，确保充分冲洗预处理。用于预清洁过滤装置的50 mL待测样品，倒入经酸洗的Nalgene滤液接收瓶中摇晃预处理后弃去。随后正式过滤样品，将滤液转移至接收瓶中，每份样品保留4~6 L滤液用于分析。向滤液中加入浓硝酸（默克Tracepur级），添加比例为2 mL/L，完成保存。

对于现场空白样，取约一半的1 L样品进行过滤并保存，剩余500 mL经酸化后留存以备后续分析，通过过滤与未过滤现场空白样的差异判断过滤过程是否引入污染。

总悬浮颗粒物(TSS)及TSS结合态金属分析所需的悬浮沉积物样品，通过将已知体积的水样过滤至预称重的0.45 μm密理博微孔滤膜上获得。滤膜使用前需用10%硝酸冲洗，过滤流程与前述一致。样品过滤完成并移除滤液后，用约20 mL去离子水冲洗过滤装置上腔及滤膜以去除盐分。将滤膜放入酸洗后的塑料培养皿中冷冻保存。将滤膜转运至CSIRO卢卡斯高地实验室后，在60 ℃下烘箱烘干，置于干燥器中冷却至室温后称重，重复该操作三次直至质量稳定，随后将滤膜室温保存以待总可回收金属分析。水样的TSS浓度（mg/L）通过滤膜过滤前后的质量差除以过滤水样体积计算得到。

### 溶解态金属分析
过滤后样品中的溶解态镉(Cd)、钴(Co)、铜(Cu)、镍(Ni)、铅(Pb)及锌(Zn)采用络合-溶剂萃取法预富集后，通过电感耦合等离子体质谱法(ICPMS)定量。该萃取流程可将金属预富集25倍，提升定量准确性。实验采用基于Magnusson与Westerlund（1981）的二硫代氨基甲酸盐络合-溶剂萃取方法，主要调整为使用碳酸氢钠缓冲液/吡咯烷二硫代氨基甲酸铵复合试剂（Apte与Gunn, 1987），并以1,1,1-三氯乙烷替代氟利昂作为萃取溶剂。具体流程为：取250 mL样品等分试样，加入复合试剂将pH缓冲至5，用两份10 mL三重蒸馏三氯乙烷萃取，合并萃取液后将金属反萃取至1 mL浓硝酸（默克Tracepur级）中，将反萃取液用去离子水定容至10 mL，采用安捷伦7500CE型电感耦合等离子体质谱仪，按照厂商推荐的仪器操作条件进行分析。为保障质量控制，每批次样品均同步分析加拿大国家研究委员会(NRC)制备的海水标准参考物质(CRM) NASS-6。

溶解态铝(Al)和铁(Fe)浓度直接采用电感耦合等离子体原子发射光谱法(ICP-AES，Varian730 ES型)测定，使用基体匹配标准溶液校准。溶解态铬(Cr)浓度经去离子水三倍稀释后，采用电感耦合等离子体质谱法(ICPMS，安捷伦7500CE型)直接测定，同样使用基体匹配标准溶液校准。

过滤样品中的溶解态砷浓度采用氢化物发生原子吸收光谱法(HG-AAS)测定，流程基于美国公共卫生协会(APHA, 1998)的标准方法：首先向样品中加入过硫酸钾（终浓度1% m/v），置于高压灭菌锅加热至120 ℃保持30分钟进行消解；随后加入盐酸（终浓度3 mol/L），加入碘化钾（终浓度1% m/v）与抗坏血酸（终浓度0.2% m/v）将五价砷预还原为三价砷，室温静置至少30分钟后待测。使用瓦里安VGA系统，按照厂商推荐的标准条件通过HG-AAS测定砷浓度：溶液中的三价砷经硼氢化钠还原为砷化氢，由氩气吹扫至925 ℃加热的石英管中，砷化氢分解为砷蒸气，通过原子吸收光谱法定量。

为保障质量控制，每批次样品均同步分析加拿大国家研究委员会(NRC)制备的海水标准参考物质(CRM) NASS-6。

溶解有机碳(DOC)采用岛津TOC-LCSH型总有机碳分析仪，按照厂商推荐的流程，对2018年6月调查采集的过滤水样等分试样进行测定。

### 总悬浮颗粒物(TSS)结合态金属及底泥沉积物金属分析
将承载悬浮沉积物的滤膜或定量干底泥样品放入经预处理的特氟龙消解罐中，采用微波辅助消解系统(MARS)进行王水消解。消解流程为：向每个消解罐中加入2.5 mL浓硝酸（Tracepur级，默克）与7.5 mL浓盐酸（Tracepur级，默克），在MARS系统中高压加热90分钟。待冷却后，打开消解罐排气，用去离子水将消解液定容至40 mL。记录消解罐空载、装载样品后以及加入酸混合物加热前后的质量，用于计算稀释因子，以反推初始未稀释样品中的金属浓度。为保障质量控制，每批次样品均同步分析欧盟标准物质与测量研究所(IRMM)制备的沉积物标准参考物质ERM-CC018及加拿大国家研究委员会(NRC)制备的PACS-3。

## 数据集格式
本数据集包含多个逗号分隔值(CSV)表格，收录了项目团队提供的全部数据。

## 数据存储位置
本数据集存储于eAtlas永久数据存储库中，路径为：dataNESP-TWQ-22.2.2_TS-mine-pollution