该议定书建立的项目由国家海洋和大气管理局 (NOAA) 海洋碎片计划 (NA16NO29990029) 提供经费。我们感谢伊利诺伊州奥尔顿国家大河研究和教育中心 (NGRREC) 的迈尔斯. 科克伦, 以帮助选址和船上操作。现场和实验室的工作是在卡米尔. 巴克利, 迈克尔. Abegg, 和丽贝卡. 瓦格纳的帮助下完成的。

1. 水样采集
<ol><li>收集水样本和水质量数据的利益乘船的河流是良好的混合, 理想的地方, 河流阶段或排放已知 (例如,美国地质调查 (USGS) 测量站)。20要保证水是混合的, 用手持式仪表在河中浸泡, 在电导率保持相对恒定的地方引导小船。</li>
	<li>在取样点, 记录位置坐标和深度。要找到0.6 深度, 只需将总深度乘以0.6。使用手持式仪表测量感兴趣的水质参数 (如浊度、温度、电导率、pH 值和溶解氧)。要测量参数, 将所需深度的取样水泵入宽口容器, 使用蠕动泵, 并立即进行测量 (步骤 1.5)。</li>
	<li>使用带有油管的蠕动泵从表面和0.6 深度获取样品。将正确的油管长度连接到泵上, 以获得给定的深度。<ol>
<li>由于在河流系统的强大电流, 连接一个6.4 毫米焊接链到泵油管使用 zip 领带, 以帮助重量的油管。在链条的末端, 放置一个重量或水泥块进一步重量的链条和油管总成。 警告:不要将重量或水泥块直接附着在泵油管上。</li>
	</ol>
</li>
	<li>把油管的出水端放在船的边缘, 远离可能脱落纤维的衣物。慢慢降低油管进水端到所需深度 (即,表面或0.6 深度)。然后, 运行在反向泵, 以空气中的油管清洗至少三十年代。在空气净化后, 反转泵的方向, 并从所需深度的样品水冲洗油管, 同时允许水排出船或废物容器。在油管冲洗至少三十年代后, 停止泵。</li>
	<li>用取样水冲洗三次用于水质测量的容器, 每次倾倒漂洗水。冲洗后, 用取样水将容器装满, 用手持式仪表测量所感兴趣的水质参数 (步骤 1.2)。</li>
	<li>收集 microplastic 亚组, 将油管出水放入一个标有1升的容器中, 经预先冲洗至少250毫升的 DI 水三次。然后, 用样品水冲洗容器三次, 每次丢弃漂洗水。microplastic 容器冲洗后, 用样品填充。</li>
	<li>使用步骤1.6 中概述的相同的蠕动泵方法, 收集一个标记的250毫升瓶中的总悬浮固体 (TSS) 的亚组, 该瓶子已预冲洗至少100毫升的 DI 水三次。用水样冲洗瓶子三次, 每次都要丢弃漂洗水。一旦将 TSS 容器冲洗干净, 请将其填入样品。</li>
	<li>按照步骤 1.6-1.7 中描述的相同方式, 在现场每天至少收集一次字段 triplicates 和空白, 以进行质量保证/质量控制 (QA/QC) 目的。收集一个空白, 带两个1升容器的 DI 水的领域。用空气清洗泵管后, 打开第一容器的 DI 水, 并用步骤1.4 中描述的方法冲洗泵油管。一旦油管被冲洗, 打开第二个容器的 DI 水, 并泵入一个空的1升容器和一个250毫升瓶为 microplastic 和 TSS 空白, 分别。</li>
	<li>将 microplastic 和 TSS 标本放在冰上, 直到返回实验室, 在那里他们将储存在 20°c, 直到他们被处理。 警告:确保在样品容器中留出一些头部空间, 以便在结冰时它们不会因冰膨胀而损坏。 注:协议可以在这里暂停。</li>
</ol>2. TSS 测定
<ol><li>使用美国环境保护局 (环保局) 方法160.2 确定 TSS 与250毫升标本收集在领域23。将计算的 TSS 值与所发现的总塑料进行比较。</li>
</ol>3. Microplastic 过滤装置总成
<ol><li>用至少250毫升的 DI 水彻底冲洗过滤装置和尼龙网筛 (图 1) 三次。将所需孔径 (例如, 50 µm、100µm、300µm、500µm) 的筛网筛入每个联合接头, 其孔径尺寸从过滤装置的顶部降低到底部 (图 1A)。紧密密封各联合接头, 防止泄漏。</li>
	<li>将所需孔径 (如0.45 µm) 的混合纤维素酯膜过滤器 (142 毫米直径) 折成锥形形状, 放入过滤装置中: 注:折叠膜过滤器可提供更多的表面积, 防止过滤器堵塞。<ol>
<li>用底水湿膜过滤器。在潮湿的时候, 将膜过滤器折叠成圆锥状, 直径与过滤装置相适应。此外, 折叠一个小唇沿圆锥的边缘, 使其适合在联合关节顶部 (图 1B)。 警告:膜过滤器在折叠前必须是湿的, 以防止撕裂。</li>
		<li>将不锈钢网篮放入最后一个联合接头 (图 1C)。小心地将锥形膜过滤器放入篮子 (图 1D)。将膜过滤器的唇折叠在联合接头的边缘。 注:一旦真空应用, 网篮将支持过滤器并减少破损。</li>
	</ol>
</li>
	<li>在图 1中所见的最后一个联合接头中, 将最小所需孔径 (例如50 µm) 放在膜过滤器顶部的网状筛。 注:这将提供额外的支持, 以保持膜过滤器在过滤过程中到位。</li>
	<li>一旦所有的联合接头密封紧密, 将软管从过滤瓶的顶部连接到过滤装置的底部。然后把软管从过滤瓶的侧面连接到真空泵上, 如图 2所示。</li>
</ol><img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/57969/57969fig1.jpg"> 图 1: 过滤装置的装配.(A) 过滤装置是通过将所需孔径的网格筛放入上联合接头中组装而成。(B) 混合纤维素酯膜过滤器必须折叠成圆锥形, 以适合过滤装置的直径;锥应包括一个小唇, 以适应在联合关节的边缘, 以确保过滤器到位。(C) 将网状篮子放入联合中, 以增加膜过滤器的稳定性。(D) 将折叠膜过滤器添加到网篮中, 最小的网筛尺寸放在膜过滤器的顶部。(E) 完全组装的过滤装置。<a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/57969/57969fig1large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/57969/57969fig2.jpg"> 图 2: 过滤瓶和泵的装配.过滤瓶连接到过滤装置真空适配器使用一个明确的乙烯基油管。过滤瓶然后连接到真空泵。<a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/57969/57969fig2large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
4. 样品过滤
<ol><li>每次组装设备时, 先收集设备的空白。在收集空白之前, 用至少250毫升的 DI 水彻底冲洗设备三次。这些空白是使用步骤 4.2-4.4 中概述的步骤收集的。</li>
	<li>打开真空泵。确保真空泵的压力不超过127毫米汞, 否则膜过滤器可能会撕裂。 警告:根据样品过滤的流速, 如果沉积物堵塞网筛或膜过滤器, 过滤装置内的压力会增加。这可能导致膜过滤器的破裂, 然后才达到127毫米汞的读数。因此, 密切注意压力, 因为它可能需要调整低于127毫米汞样品根据样品。</li>
	<li>使用500毫升的毕业气缸, 三重冲洗至少250毫升的 DI 水, 以测量样品的总容积。记录体积并将样品从毕业气缸转移到过滤装置。 警告:根据水样和过滤瓶的大小, 过滤瓶在样品过滤过程中可能需要多次清空。<ol>
<li>要清空过滤瓶, 请关闭泵并将两个软管从烧瓶中分离出来。把瓶子倒进一个单独的废物容器里。 警告:保持过滤样品水, 直到整个样品被过滤, 并确认膜过滤器是完整的。</li>
		<li>要继续过滤循环, 请将软管重新连接到过滤瓶, 如步骤3.4 中所述, 然后打开泵。</li>
	</ol>
</li>
	<li>一旦整个样品被过滤, 冲洗样品容器和毕业圆筒三次以至少250毫升的 DI 水。每次冲洗后, 过滤水冲洗容器和毕业汽缸, 以确保所有微粒已被过滤。</li>
</ol>5. Microplastic 过滤装置拆卸
<ol><li>用至少250毫升的 DI 水冲洗过滤装置的墙壁三次, 以确保所有微粒都被过滤, 并且没有残留在过滤装置上。</li>
	<li>关闭真空泵, 然后仔细拧开并分离第一个接头。将泵重新打开, 使用二水冲洗瓶冲洗接头的边缘。将滤网筛边缘的微粒清洗成中心, 以确保全部收集。</li>
	<li>将泵关闭, 用干净的镊子小心地取出网筛, 确保不接触筛网表面的微粒。将网筛放入覆盖的培养皿中, 干燥60ᵒC 24 小时。一旦干燥, 样品可以储存, 直到分析可以开始。</li>
	<li>重复步骤 5.1-5.3 为每个联合联合住房一个网状筛子。</li>
	<li>对于最后一个结合网格筛和膜过滤器的联合接头, 重复步骤 5.1-5.3 为网筛。 警告:冲洗网筛时要小心, 如在滤膜过滤器下冲洗样品就会丢失。</li>
	<li>用二水冲洗瓶将真空泵打开, 冲洗膜过滤器的边缘。将膜过滤器边缘的微粒洗涤到中心, 以确保过滤完整的样品。在拆卸膜过滤器之前, 要确保所有的水都经过它, 并且没有水在其表面上聚集。 警告:再次, 清洗膜过滤器时要小心, 如果在它下面冲洗样品可以丢失。</li>
	<li>用镊子小心地取出和展开膜过滤器。将膜过滤器放到适合其直径的培养皿或箔包中。 注:滤膜过滤器在处理时必须受潮, 以防撕裂。</li>
	<li>将所述膜过滤器在烤箱中干燥60ᵒC 24 小时。一旦干燥, 储存样品, 直到分析可以开始。 注:协议可以在这里暂停。</li>
</ol>6. 微粒分析
<ol><li>将筛网或滤膜过滤器留在培养皿中, 取出盖子, 开始检查样品的 microplastics。这将确保, 如果任何微粒脱落的筛网或膜过滤器, 他们将留在培养皿, 可以分析后, 所有微粒从筛网或膜过滤器去除。</li>
	<li>检查网筛或膜过滤器下的显微镜 (14-90X 放大), 以识别可疑的塑料微粒和纤维。在识别怀疑塑料时, 使用以下标准: 没有蜂窝结构, 纤维在整个过程中都是相等的, 粒子不发亮24。</li>
	<li>从筛网或滤膜过滤器中取出所有怀疑的塑料, 放入含有70% 乙醇的收集瓶中。记录每个可疑塑料的颜色和形状 (如微粒、纤维、胶片等)。</li>
	<li>一旦所有怀疑的塑料从筛网或滤膜过滤器中取出, 并量化, 检查的盖子和底部的培养皿后步骤 6.2-6.3。</li>
	<li>在筛网或膜过滤器和培养皿被检查和所有怀疑塑料去除和量化后, 将微粒或纤维从收集瓶放置到12槽铝涂层幻灯片上进行分析, 使用微量的 ATR 红外光谱分析。 注:在微红外光谱上测试每种怀疑的塑料并不总是可行的。因此, "战略性地选择" 将解决研究目标和怀疑塑料中的异常 (例如,大量类似纤维或颗粒) 的数量25。从一般意义上说, 测试尽可能多的怀疑塑料, 但不少于20%。<ol>
<li>一旦怀疑塑料的分析使用微型 ATR-FTIR, 使用光谱数据库, 以确定是否一个给定的样品是塑料的, 如果是这样, 确定塑料的聚合物类型。</li>
	</ol>
</li>
</ol>

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B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fishery+Production+and+the+Mississippi+River.">Fishery Production and the Mississippi River.</a> Fisheries. 28 (8), 17-26 (2001).</li><li>Talvitie, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Do+wastewater+treatment+plants+act+as+a+potential+point+source+of+microplastics?+Preliminary+study+in+the+coastal+Gulf+of+Finland,+Baltic+Sea.">Do wastewater treatment plants act as a potential point source of microplastics? Preliminary study in the coastal Gulf of Finland, Baltic Sea.</a> Water Science and Technology. 72 (9), 1495-1504 (2015).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> United States Environmental Protection Agency (USEPA) Method 160.2: Residue, Non-filtereable (Gravimetric, Dried at 103-105C). , (1971).</li><li>Nor, N. H., Obbard, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microplastics+in+Singapore's+coastal+mangrove+ecosystems.">Microplastics in Singapore's coastal mangrove ecosystems.</a> Marine Pollution Bulletin. 79 (1-2), 278-283 (2014).</li><li>Woodall, L. C., Gwinnett, C., Packer, M., Thompson, R. C., Robinson, L. F., Paterson, G. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+a+forensic+science+approach+to+minimize+environmental+contamination+and+to+identify+microfibres+in+marine+sediments.">Using a forensic science approach to minimize environmental contamination and to identify microfibres in marine sediments.</a> Marine Pollution Bulletin. 95 (1), 40-46 (2015).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> S. 1424 - 114th Congress: Microbead-Free Waters Act of 2015. , (2015).</li></ol>

作者没有什么可透露的。

Microplastic 收集使用漂移网是传统的方法, 在海洋环境, 如泥沙和塑料浓度低, 因此需要大量的样本量。然而, 在高泥沙荷载和大型漂浮或淹没的河流中, 漂移网并不总是切实可行或安全的。此外, 在试图彻底捕获和量化 microplastic 材料 (尤其是纤维) 时, 使用漂移网是不可行的, 因为大多数用于塑料测量的网都有网格尺寸≥300µm。本文所描述的协议允许在含有高泥沙负荷的水体中进行取样, 同时允许捕获...

最早在二十世纪三十年代1, 塑料首次在海洋中被观测到。最近对海洋塑料碎片的估计范围从海洋表面的塑料超过24.3万公吨 (mt) 到 4.8-1270万吨塑料, 每年从陆地来源进入大洋2,3。早期对海洋塑料碎片的研究侧重于 macroplastics (> 5 毫米直径), 因为它们很容易看到和量化。然而, 最近发现, macroplastics 代表 < 10% 的塑料碎片, 计数, 在海洋中, 表明绝大多数的塑料碎片是 microplastic (< 5 毫米直径)2。
Microplastics 分为两组: 初级和二级 Microplastics。主要 microplastics 由直径 < 5 毫米制造的塑料组成, 包括塑料球, 用于制造消费品的原料, 微球用作个人护理产品中的 exfoliants (例如,洗脸、身体磨砂、牙膏), 以及在工业中的磨料或润滑剂。次级 microplastics 是在环境中创建的, 因为较大的塑料碎片被光解、磨损和微生物分解4,5碎片。合成纤维也是次要的 microplastics 并且是越来越关心。一个单一的服装可以释放 > 1900 纤维每洗涤在国内洗衣机6。这些纤维, 以及个人护理产品的微珠, 在进入废水处理厂之前, 都被冲进下水道并进入排污系统。墨菲 (2016) 发现, 一个65万人口的污水处理厂将 microplastic 浓度减少了 98.4%, 从进水到出水, 但 6500万 microplastics 在废水和污泥中保持每天7。即使在处理过程中 microplastics 的比例很高, 千百万人, 可能是亿万, microplastics 通过废水处理厂每天和进入地表水在污水6,8 ,9,10,11。
由于其环境的释放, microplastics 在所有营养水平12,13,14,15的海洋生物的消化和呼吸组织中发现。它们在吸收后的影响是可变的, 有些研究没有观察到伤害, 而另一些则显示了许多影响, 如物理和化学组织损伤4,6,14,15。由于这些发现, 这一领域的兴趣在过去五年中有所增加。然而, 最近才开始对淡水系统, 如河流和湖泊中的塑料碎片 (特别是 microplastics) 进行量化研究, 或评估对居住在这些生境12、16的生物的影响, 17,18。河流是海洋中发现的塑料碎片的主要来源, 因为它们接收到含 microplastics 和 macroplastics 的废水和地表水径流。
此处详述的协议可用于收集不可行的漂移网的 microplastic 样本;具体来说, 在水生环境中, 悬浮沉积物高度集中, 像密西西比河这样的大型漂浮碎屑。密西西比河流域是世界上最大的、拥有 > 9000万人口的国家之一, 这可能使它成为海洋中最大的塑料碎片来源19,20。每年, 密西西比河平均排放735公里3的淡水到墨西哥湾, 以及高浓度的悬浮沉积物 (60 至 > 800 毫克/升) 和大碎片13,21。在密西西比河及其支流的两个深度 (即表面和0.6 深度) 收集水样, 使用蠕动泵在半透明的 1 L 低密度聚乙烯 (PE) 容器中。在实验室中, 用尼龙网筛和混合纤维素酯膜过滤器同时过滤样品, 用特制的63.5 毫米 (2.5 英寸) 聚氯乙烯 (PVC) 气缸与联合接头插入筛和过滤器22。在过滤装置中加入 PVC 联合, 可以根据需要尽可能多或少量的粒度类进行过滤。此外, 它还可用于在研究合成纤维时使用膜过滤器捕获 microplastic 碎片到亚微米尺寸。过滤后 , 样品燥 , 怀疑塑料被识别和分类从网筛和膜过滤器下的显微镜。然后用微衰减的全反射傅里叶变换红外光谱 (微型 ATR-FTIR) 研究了怀疑塑料, 以消除非合成材料或确定聚合物类型。考虑到 microplastic 颗粒和纤维的大小, 污染是司空见惯的。污染来源包括大气沉积物、衣物、田间和实验室设备以及去离子 (DI) 水资源。在整个《议定书》中包括多个步骤, 以减少来自不同来源的污染, 同时进行研究的所有阶段。

<table border="0" cellpadding="0" cellspacing="0" style="width:1076px;" width="1075">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">1L Cubitainer Containers, Low-Density Polyethylene</td>
			<td style="width:127px;">VWR</td>
			<td style="width:119px;">89094-140</td>
			<td style="width:612px;">Containers used to collect and store samples.</td>
		</tr>
		<tr height="126">
			<td height="126" style="height:126px;width:219px;">2-1/2&#34; Clear Schedule 40 Rigid PVC Pipe</td>
			<td style="width:127px;">United States Plastic Corporation</td>
			<td style="width:119px;">34138</td>
			<td style="width:612px;">The PVC pipe used to make the device comes as an 2.43 m pipe. The pipe was then cut to the desired lengths for each section seperated by union joints. Section lengths were decided by predicting smaller pore sizes would clogg the device quicker. Longer sections were placed above the smaller pore sizes to collect and hold water to prevent needing to disassemble the device to change a filter while a sample remained in the device. For one filtration device one 18 in, one 12 in, and two 6 in peices are needed.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">2-1/2&#34; PVC SCH 40 Socket Union&#160;</td>
			<td style="width:127px;">Supply House</td>
			<td style="width:119px;">457-025</td>
			<td style="width:612px;">Union joints were glued to PVC pipe to house nylon sieves and mixed cellulose membranes.</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:219px;">Nylon 6 Woven Mesh Sheet, Opaque Off-White, 12&#34; Width, 12&#34; Length, 500 microns Mesh Size, 38% Open Area (Pack of 5)</td>
			<td style="width:127px;">Small Parts via Amazon</td>
			<td style="width:119px;">CMN-0500-C/5PK-05</td>
			<td style="width:612px;">Mesh sheets were cut into circles to match the diameter of the outer diameter of the PVC pipe. The edges were glued to esure no fraying would occur. The glue &#39;s diamter should not extend into the inner diameter of the PVC so that it will not be affected during filtration.&#160;</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:219px;">Nylon 6 Woven Mesh Sheet, Opaque White, 12&#34; Width, 12&#34; Length, 100 microns Mesh Size, 44% Open Area (Pack of 5)</td>
			<td style="width:127px;">Small Parts via Amazon</td>
			<td style="width:119px;">B0043D1TB4</td>
			<td style="width:612px;">Mesh sheets were cut into circles to match the diameter of the outer diameter of the PVC pipe. The edges were glued to esure no fraying would occur. The glue &#39;s diamter should not extend into the inner diameter of the PVC so that it will not be affected during filtration.&#160;</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:219px;">Nylon 6 Woven Mesh Sheet, Opaque White, 12&#34; Width, 12&#34; Length, 50 microns Mesh Size, 37% Open Area (Pack of 5)</td>
			<td style="width:127px;">Small Parts via Amazon</td>
			<td style="width:119px;">B0043D1SGA</td>
			<td style="width:612px;">Mesh sheets were cut into circles to match the diameter of the outer diameter of the PVC pipe. The edges were glued to esure no fraying would occur. The glue &#39;s diamter should not extend into the inner diameter of the PVC so that it will not be affected during filtration.&#160;</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:219px;">Mixed Cellulose Ester Membrane, 0.45um, 142mm, 25/pk</td>
			<td style="width:127px;">VWR</td>
			<td style="width:119px;">10034-914</td>
			<td style="width:612px;">Mixed cellulose membrane filter with 0.45 um was used as the last filter. A large diameter was used to allow the filter to be folded into a cone to increase surface area of the filter to prevent clogging.&#160;</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:219px;">Metal Mesh Basket Tea Leaves Strainer Teapot Filter 76mm Dia 3pcs</td>
			<td style="width:127px;">Uxcell via Amazon</td>
			<td style="width:119px;">a15071600ux0260</td>
			<td style="width:612px;">The mesh basket used to provide extra support for the membrane filter to prevent tearing when pressure was applied by a vacuum pump.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">1/2&#34; PVC Barbed Insert Male Adapter</td>
			<td style="width:127px;">Supply House</td>
			<td style="width:119px;">1436-005</td>
			<td style="width:612px;">A vacuum adapter was added to allow vacuum filtration in the case of slow filtration due to high sediment concentration.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">1/2 in. O.D. x 3/8 in. I.D. x 10 ft. PVC Clear Vinyl Tube</td>
			<td style="width:127px;">Home Depot</td>
			<td style="width:119px;">702229</td>
			<td style="width:612px;">Tubing used to connect the vacuum pump to the filtration device.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:219px;">YSI Professional Plus Multiparameter Instrument with Quatro Cable</td>
			<td style="width:127px;">YSI</td>
			<td>6050000</td>
			<td style="width:612px;">Handheld meter used to measure additional water quality parameters parameters (e.g., turbidity, temperature, conductivity, pH, and dissolved oxygen (DO)).</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:219px;">2100P Portable Turbidimeter</td>
			<td style="width:127px;">Hach</td>
			<td style="width:119px;">4650000</td>
			<td style="width:612px;">Handheld meter used to measure turbidity.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">FEP-lined PE tubing</td>
			<td style="width:127px;">Geotech</td>
			<td style="width:119px;">87050529</td>
			<td style="width:612px;">Tubing used with perestaltic pump to collect water samples from desired depths.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Geopump Peristaltic Pump Series II</td>
			<td style="width:127px;">Geotech</td>
			<td style="width:119px;">91350123</td>
			<td style="width:612px;">Pump used to collected water samples.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">MeiJi Techno EMZ-8TR Microscope</td>
			<td style="width:127px;">Microscope.com</td>
			<td style="width:119px;">EMZ8TR-PLS2</td>
			<td style="width:612px;">Microscope used analyze mesh sieves and membrane filters to quanitfy suspect microsplastics.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Nicolet iS10 FTIR Spectrometer</td>
			<td style="width:127px;">Thermo Electron North America</td>
			<td style="width:119px;">912A0607</td>
			<td style="width:612px;">FTIR used to analyze suspect microplastics.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Nicolet iN5 FTIR microscope</td>
			<td style="width:127px;">Thermo Electron North America</td>
			<td style="width:119px;">912A0895</td>
			<td style="width:612px;">FTIR microscope used to analyze suspect microplastics.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Germanium (Ge) ATR</td>
			<td style="width:127px;">Thermo Electron North America</td>
			<td style="width:119px;">869-174400</td>
			<td style="width:612px;">Geranium ATR accessory used along with the Nicolet iN5 FTIR microscope to analyze suspect microplastic.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Aluminum EZ-Spot Micro Mounts (Pkg of 5)</td>
			<td style="width:127px;">Thermo Electron North America</td>
			<td style="width:119px;">0042-545</td>
			<td style="width:612px;">Microscope slides used along with the Nicolet iN5 FTIR microscope to analyze suspect microplastic.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:219px;">Aluminum Coated Glass Sample Slides</td>
			<td style="width:127px;">Thermo Electron North America</td>
			<td style="width:119px;">0042-544</td>
			<td style="width:612px;">Microscope slides used along with the Nicolet iN5 FTIR microscope to analyze suspect microplastic.</td>
		</tr>
	</tbody>
</table>

sampling, sorting, and characterizing microplastics in aquatic environments with high suspended sediment loads and large floating debris

在海洋中普遍存在的塑料碎片被公众、科学界和政府机构广泛认可。然而, 只有最近才在淡水系统, 如河流和湖泊中 microplastics, 被量化。Microplastic 抽样在表面通常包括部署漂移网在一个固定或移动的小船之后, 它限制取样对低水平悬浮的沉淀物和漂浮或被淹没的残骸的环境。以前的研究, 利用漂移网收集 microplastic 碎片通常使用网与≥300µm 网格大小, 允许塑料碎片 (颗粒和纤维) 低于这个大小, 通过网络和逃避量化。此处详述的协议使: 1) 在高悬浮荷载和漂浮或浸没碎片的环境中采集样本, 2) 对 microplastic 颗粒和纤维 < 300 µm 的捕获和定量. 用一种蠕动泵在低密度聚乙烯 (PE) 容器中储存, 然后在实验室进行过滤和分析。过滤是由一个定制的 microplastic 过滤装置, 其中包含了尼龙网状筛和混合纤维素酯膜过滤器可拆卸的联合关节。用显微镜对网筛和膜过滤器进行了定量和分离 microplastic 微粒和纤维的研究。然后用微衰减的全反射傅里叶变换红外光谱仪 (microplastic) 对这些材料进行了检测, 以确定聚合物的类型。采用蓝色 PE 微粒和绿色尼龙纤维对样品进行了峰值检测;测定颗粒物的回收率为 100%, 纤维含量为92%。该议定书将指导类似的研究 microplastics 在高浓度的河流泥沙。通过对蠕动泵和过滤装置的简单修改, 用户可以收集和分析各种样品体积和颗粒尺寸。

为了验证此协议的恢复率, 三个样本 (v1-v3) 从 Oso 湾, 科珀斯克里斯蒂, 得克萨斯州 (毗邻得克萨斯州 A & M 大学科珀斯克里斯蒂校区), 与10蓝色 PE 微粒 (范围从50-100 µm直径) 和50种不同长度的绿色尼龙纤维 (图 3)。计算了样本的 TSS (2 节), 然后用3-5 节中概述的方法对样品进行过滤。蓝色 PE 微粒和绿色尼龙纤维然后被分离和定量 (表 1...

Watch this Scientific Journal Video about Sampling, Sorting, and Characterizing Microplastics in Aquatic Environments with High Suspended Sediment Loads and Large Floating Debris at JoVE.com

Sampling, Sorting, and Characterizing Microplastics in Aquatic Environments with High Suspended Sediment Loads and Large Floating Debris

高悬浮泥沙荷载和大型漂浮碎屑水生环境中 Microplastics 的取样、分类和表征

迄今为止, 大多数 microplastic 研究都发生在海洋系统中, 悬浮固体水平相对较低。重点现在转移到淡水系统, 这可能具有高泥沙负荷和漂浮的碎片。该协议涉及收集和分析含有高悬浮固体负荷的水生环境中的 microplastic 样品。

The ubiquitous presence of plastic debris in the ocean is widely recognized by the public, scientific communities, and government agencies. However, only ...

sampling-sorting-characterizing-microplastics-aquatic-environments

Universidad de Cartagena UDEC

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Environment

15.8K 次观看.  Texas A&M University-Corpus Christi. 迄今为止, 大多数 microplastic 研究都发生在海洋系统中, 悬浮固体水平相对较低。重点现在转移到淡水系统, 这可能具有高泥沙负荷和漂浮的碎片。该协议涉及收集和分析含有高悬浮固体负荷的水生环境中的 microplastic 样品。

视频: Sampling, Sorting, and Characterizing Microplastics in Aquatic Environments with High Suspended Sediment Loads and Large Floating Debris

Sediment Core Sectioning and Extraction of Pore Waters under Anoxic Conditions

We demonstrate a method for sectioning sediment cores and extracting pore waters while maintaining oxygen-free conditions. A simple, inexpensive system is built and can be transported to a temporary work space close to field sampling site(s) to facilitate rapid analysis. Cores are extruded into a portable glove bag, where they are sectioned and each 1-3 cm thick section (depending on core diameter) is sealed into 50 ml centrifuge tubes. Pore waters are separated with centrifugation outside of the glove bag and then returned to the glove bag for separation from the sediment. These extracted pore water samples can be analyzed immediately. Immediate analyses of redox sensitive species, such as sulfide, iron speciation, and arsenic speciation indicate that oxidation of pore waters is minimal; some samples show approximately 100% of the reduced species, e.g. 100% Fe(II) with no detectable Fe(III). Both sediment and pore water samples can be preserved to maintain chemical species for further analysis upon return to the laboratory.

A protocol for sectioning sediment cores and extracting pore waters under anoxic conditions in order to permit analysis of redox sensitive species in both solids and fluids is presented.

沉积物核心切片和孔隙水萃取缺氧条件下

We demonstrate a method for sectioning sediment cores and extracting pore waters while maintaining oxygen-free conditions. A simple, inexpensive system is ...

科研

环境科学

Characterization and Application of Passive Samplers for Monitoring of Pesticides in Water

Five different water passive samplers were calibrated under laboratory conditions for measurement of 124 legacy and current used pesticides. This study provides a protocol for the passive sampler preparation, calibration, extraction method and instrumental analysis. Sampling rates (RS) and passive sampler-water partition coefficients (KPW) were calculated for silicone rubber, polar organic chemical integrative sampler POCIS-A, POCIS-B, SDB-RPS and C18 disk. The uptake of the selected compounds depended on their physicochemical properties, i.e., silicone rubber showed a better uptake for more hydrophobic compounds (log octanol-water partition coefficient (KOW) &#62; 5.3), whereas POCIS-A, POCIS-B and SDB-RPS disk were more suitable for hydrophilic compounds (log KOW &#60; 0.70).

A protocol about the characterization and application of five different passive sampling devices is presented.

表征和被动采样的应用在农药水监测

Five different water passive samplers were calibrated under laboratory conditions for measurement of 124 legacy and current used pesticides. This study ...

A Flow-through Exposure System for Evaluating Suspended Sediments Effects on Aquatic Life

This paper describes the Fish Larvae and Egg Exposure System (FLEES). The flow-through exposure system is used to investigate the effects of suspended sediment on various aquatic species and life stages in the laboratory by using pumps and automating delivery of sediment and water to simulate suspension of sediment. FLEES data are used to develop exposure-response curves between the effects on aquatic organisms and suspended sediment concentrations at the desired exposure duration. The effects data are used to evaluate management practices used to reduce the interactions between aquatic organisms and anthropogenic causes of suspended sediments. The FLEES is capable of generating total suspended solids (TSS) concentrations as low as 30 to as high as 800 mg/L, making this system an ideal choice for evaluating the effects of TSS resulting from many activities including simulating low ambient levels of TSS to evaluating sources of suspended sediments from dredging operations, vessel traffic, freshets, and storms.

A robust and flexible flow-through exposure system designed to maintain sediment in suspension is presented. The system is used to investigate the effects of suspended sediment on various aquatic species and life stages in the laboratory.

对水生生命值评价悬浮泥沙影响的流通系统曝光

This paper describes the Fish Larvae and Egg Exposure System (FLEES). The flow-through exposure system is used to investigate the effects of suspended ...

Protocol for Microplastics Sampling on the Sea Surface and Sample Analysis

Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of scientific publications address microplastic pollution of the sea surface. The protocol below describes the methodology for sampling, sample preparation, separation and chemical identification of microplastic particles. A manta net fixed on an &#187;A frame&#171; attached to the side of the vessel was used for sampling. Microplastic particles caught in the cod end of the net were separated from samples by visual identification and use of stereomicroscopes. Particles were analyzed for their size using an image analysis program and for their chemical structure using ATR-FTIR and micro FTIR spectroscopy. The described protocol is in line with recommendations for microplastics monitoring published by the Marine Strategy Framework Directive (MSFD) Technical Subgroup on Marine Litter. This written protocol with video guide will support the work of researchers that deal with microplastics monitoring all over the world.

The protocol below describes the methodology for: microplastics sampling on the sea surface, separation of microplastic and chemical identification of particles. This protocol is in line with the recommendations for microplastics monitoring published by the MSFD Technical Subgroup on Marine Litter.

协议塑料微粒采样的海面和样品分析

Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of ...

A Lipid Extraction and Analysis Method for Characterizing Soil Microbes in Experiments with Many Samples

Microbial communities are important drivers and regulators of ecosystem processes. To understand how management of ecosystems may affect microbial communities, a relatively precise but effort-intensive technique to assay microbial community composition is phospholipid fatty acid (PLFA) analysis. PLFA was developed to analyze phospholipid biomarkers, which can be used as indicators of microbial biomass and the composition of broad functional groups of fungi and bacteria. It has commonly been used to compare soils under alternative plant communities, ecology, and management regimes. The PLFA method has been shown to be sensitive to detecting shifts in microbial community composition.
An alternative method, fatty acid methyl ester extraction and analysis (MIDI-FA) was developed for rapid extraction of total lipids, without separation of the phospholipid fraction, from pure cultures as a microbial identification technique. This method is rapid but is less suited for soil samples because it lacks an initial step separating soil particles and begins instead with a saponification reaction that likely produces artifacts from the background organic matter in the soil. 
This article describes a method that increases throughput while balancing effort and accuracy for extraction of lipids from the cell membranes of microorganisms for use in characterizing both total lipids and the relative abundance of indicator lipids to determine soil microbial community structure in studies with many samples. The method combines the accuracy achieved through PLFA profiling by extracting and concentrating soil lipids as a first step, and a reduction in effort by saponifying the organic material extracted and processing with the MIDI-FA method as a second step.

The article describes a method that increases throughput while balancing effort and accuracy for extraction of lipids from the cell membranes of microorganisms for use in characterizing both total lipids and the relative abundance of indicator lipids to determine soil microbial community structure in studies with many samples.

用于表征土壤微生物的脂质提取和分析方法在许多样品的实验中

Microbial communities are important drivers and regulators of ecosystem processes. To understand how management of ecosystems may affect microbial ...

Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds

Pollutant concentrations and loads in watersheds vary considerably with time and space. Accurate and timely information on the magnitude of pollutants in water resources is a prerequisite for understanding the drivers of the pollutant loads and for making informed water resource management decisions. The commonly used &#34;grab sampling&#34; method provides the concentrations of pollutants at the time of sampling (i.e., a snapshot concentration) and may under- or overpredict the pollutant concentrations and loads. Continuous monitoring of nutrients and sediment has recently received more attention due to advances in computing, sensing technology, and storage devices. This protocol demonstrates the use of sensors, sondes, and instrumentation to continuously monitor in situ nitrate, ammonium, turbidity, pH, conductivity, temperature, and dissolved oxygen (DO) and to calculate the loads from two streams (ditches) in two agricultural watersheds. With the proper calibration, maintenance, and operation of sensors and sondes, good water quality data can be obtained by overcoming challenging conditions such as fouling and debris buildup. The method can also be used in watersheds of various sizes and characterized by agricultural, forested, and/or urban land.

With the advancement of technology and the rise in end-user expectations, the need and use of higher temporal resolution data for pollutant load estimation has increased. This protocol describes a method for continuous in situ water quality monitoring to obtain higher temporal resolution data for informed water resource management decisions.

农业流域营养盐和泥沙的连续河道监测

Pollutant concentrations and loads in watersheds vary considerably with time and space. Accurate and timely information on the magnitude of pollutants in ...

Characterization of Aquatic Biofilms with Flow Cytometry

Biofilms are dynamic consortia of microorganism that play a key role in freshwater ecosystems. By changing their community structure, biofilms respond quickly to environmental changes and can be thus used as indicators of water quality. Currently, biofilm assessment is mostly based on integrative and functional endpoints, such as photosynthetic or respiratory activity, which do not provide information on the biofilm community structure. Flow cytometry and computational visualization offer an alternative, sensitive, and easy-to-use method for assessment of the community composition, particularly of the photoautotrophic part of freshwater biofilms. It requires only basic sample preparation, after which the entire sample is run through the flow cytometer. The single-cell optical and fluorescent information is used for computational visualization and biological interpretation. Its main advantages over other methods are the speed of analysis and the high-information-content nature. Flow cytometry provides information on several cellular and biofilm traits in a single measurement: particle size, density, pigment content, abiotic content in the biofilm, and coarse taxonomic information. However, it does not provide information on biofilm composition on the species level. We see high potential in the use of the method for environmental monitoring of aquatic ecosystems and as an initial biofilm evaluation step that informs downstream detailed investigations by complementary and more detailed methods.

Flow cytometry in combination with visual clustering offers an easy-to-use and fast method for studying aquatic biofilms. It can be used for biofilm characterization, detection of changes in biofilm community structure, and detection of abiotic particles embedded in the biofilm.

流式细胞仪对水生生物膜的表征

Biofilms are dynamic consortia of microorganism that play a key role in freshwater ecosystems. By changing their community structure, biofilms respond ...

Detection of 3-Nitrotyrosine in Atmospheric Environments via a High-performance Liquid Chromatography-electrochemical Detector System

3-nitrotyrosine (3-NT) is generated from the tyrosine residue in atmospheric bio-aerosol proteins via a reaction with ozone (O3) and nitrogen dioxide (NO2). Stable 3-NT is a specific marker for oxidative damage and is reported to have a promotive effect to elicit allergies. In the present study, we report the development of a highly sensitive assay to quantify 3-NT in air sampler filters to collect &#60; 2.5 &#181;m of particulate matter (PM2.5) from urban environmental air, including bio-aerosol. In this method, a 6 mm-diameter round hole was cut from the filters of air samplers and mixed with a nonspecific protease cocktail in order to hydrolyze proteins. Protein samples digested to the amino acid level were tested for 3-NT using a high-performance liquid chromatography-electrochemical detector (HPLC-ECD). The maximum 3-NT content was detected in a prefilter for PM of sizes from 4.5 to 7.3 &#956;m, with a detection limit of 1.13 pg/m3.

Detection of 3-Nitrotyrosine in Atmospheric Environments via a High-performance Liquid Chromatography-electrochemical Detector System

We present a method to detect 3-nitrotyrosine chemical modifications of atmospheric proteins with 6 mm-diameter rounds cut from air sampler prefilters using a high-performance liquid chromatography-electrochemical detector (HPLC-ECD).

利用高效液相色谱-电化学检测仪检测大气环境中的 3-硝基酪氨酸

3-nitrotyrosine (3-NT) is generated from the tyrosine residue in atmospheric bio-aerosol proteins via a reaction with ozone (O3) and nitrogen dioxide ...

Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors

Denitrification is the primary biogeochemical process removing reactive nitrogen from the biosphere. The quantitative evaluation of this process has become particularly relevant for assessing the anthropogenic-altered global nitrogen cycle and the emission of greenhouse gases (i.e., N2O). Several methods are available for measuring denitrification, but none of them are completely satisfactory. Problems with existing methods include their insufficient sensitivity, and the need to modify the substrate levels or alter the physical configuration of the process using disturbed samples.This work describes a method for estimating sediment denitrification rates that combines coring, acetylene inhibition, and microsensor measurements of the accumulated N2O. The main advantages of this method are a low disturbance of the sediment structure and the collection of a continuous record of N2O accumulation; these enable estimates of reliable denitrification rates with minimum values up to 0.4-1 &#181;mol N2O m-2 h-1. The ability to manipulate key factors is an additional advantage for obtaining experimental insights. The protocol describes procedures for collecting the cores, calibrating the sensors, performing the acetylene inhibition, measuring the N2O accumulation, and calculating the denitrification rate. The method is appropriate for estimating denitrification rates in any aquatic system with retrievable sediment cores. If the N2O concentration is above the detection limit of the sensor, the acetylene inhibition step can be omitted to estimate the N2O emission instead of denitrification. We show how to estimate both actual and potential denitrification rates by increasing nitrate availability as well as the temperature dependence of the process. We illustrate the procedure using mountain lake sediments and discuss the advantages and weaknesses of the technique compared to other methods. This method can be modified for particular purposes; for instance, it can be combined with 15N tracers to assess nitrification and denitrification or field in situ measurements of denitrification rates.

Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors

This method estimates sediment denitrification rates in sediment cores using the acetylene inhibition technique and microsensor measurements of the accumulated N2O. The protocol describes procedures for collecting the cores, calibrating the sensors, performing the acetylene inhibition, measuring the N2O accumulation, and calculating the denitrification rate.

利用岩体和 n 2o 微传感器估计沉积物脱氮率

Denitrification is the primary biogeochemical process removing reactive nitrogen from the biosphere. The quantitative evaluation of this process has ...

Single-throughput Complementary High-resolution Analytical Techniques for Characterizing Complex Natural Organic Matter Mixtures

Natural organic matter (NOM) is composed of a highly complex mixture of thousands of organic compounds which, historically, proved difficult to characterize. However, to understand the thermodynamic and kinetic controls on greenhouse gas (carbon dioxide [CO2] and methane [CH4]) production resulting from the decomposition of NOM, a molecular-level characterization coupled with microbial proteome analyses is necessary. Further, climate and environmental changes are expected to perturb natural ecosystems, potentially upsetting complex interactions that influence both the supply of organic matter substrates and the microorganisms performing the transformations. A detailed molecular characterization of the organic matter, microbial proteomics, and the pathways and transformations by which organic matter is decomposed will be necessary to predict the direction and magnitude of the effects of environmental changes. This article describes a methodological throughput for comprehensive metabolite characterization in a single sample by direct injection Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), gas chromatography mass spectrometry (GC-MS), nuclear magnetic resonance (NMR) spectroscopy, liquid chromatography mass spectrometry (LC-MS), and proteomics analysis. This approach results in a fully-paired dataset which improves statistical confidence for inferring pathways of organic matter decomposition, the resulting CO2 and CH4 production rates, and their responses to environmental perturbation. Herein we present results of applying this method to NOM samples collected from peatlands; however, the protocol is applicable to any NOM sample (e.g., peat, forested soils, marine sediments, etc.).

This protocol describes a single throughput for complementary analytical and omics techniques culminating in a fully-paired characterization of natural organic matter and microbial proteomics in different ecosystems. This approach permits robust comparisons for identifying metabolic pathways and transformations important for describing greenhouse gas production and predicting responses to environmental change.