This work was funded by the European Union Seventh Framework Program FP7/2007-2013 under grant agreement no. 265721. The authors thank the RIKILT Institute for Food Safety (NL) for their support in this project.

Note: The following protocol describes the SPE performed on 100 ml water sample with C18 sorbent and elution with 50% v/v methanol. The enriched sample is diluted to reach 10% v/v methanol before analysis with an enzyme linked immunosorbent assay (ELISA) kit.
1. Preparing the Reagents
<ol>
	<li>Prepare the water samples
	<ol>
		<li>Prior to any other step, filter each 100 ml water sample with 0.2 &#181;m pore size filters.</li>
		<li>Spike the sample with desired concentration by diluting appropriate volume of reference solution into a volume of water. For example, prepare 100 ml of water sample with 100 ng/L of E2 by diluting 3.3 &#181;l of E2 reference solution at a concentration of 300 &#181;g/L. Dilute this solution ten times to get a sample spiked with 10 ng/L E2. Dilute this latter another ten times to obtain a sample of 100 ml with 1 ng/L E2.</li>
		<li>Place the filtered sample (unmodified or spiked) in a glass bottle with GL45 thread. Use the sample on the same day. Take a small fraction to be analyzed with the ELISA to estimate initial concentration.</li>
	</ol>
	</li>
	<li>Prepare 300 &#181;l of eluent by diluting methanol in de-ionized (di-) water to 50% v/v in a tight tube.</li>
</ol>
2. Preparation of the SPE Column
<ol>
	<li>Prepare a 20 mg/ml suspension of octadecyl-silica sorbent particles by adding first 1,600 &#181;l of methanol and then 400 &#181;l of di-water to 40 mg of reverse phase sorbent. Tightly close the lid and agitate with a vortex.</li>
	<li>Installing the bottom membrane in column
	<ol>
		<li>Select one Nylon membrane with pore size 11 &#181;m and place it on a double layer of anti-dust tissue. With a 3 mm diameter punch, cut two small parts in the membrane.</li>
		<li>Grab one of the small membranes with a flat-end filter forceps and place it on one side of the column.</li>
		<li>Screw the flat-bottom connector with the tube and tighten. The membrane is now in place and the sorbent can be added securely. Draw an arrow on the body of the column pointing towards the end where the membrane was placed.</li>
	</ol>
	</li>
	<li>Preparing the packed sorbent column
	<ol>
		<li>Secure the column on the holder with the arrow pointing towards the bottom. The column must be set as vertically as possible.</li>
		<li>Attach an empty 10 ml disposable syringe to the end of the tube of the column, by using the Luer-Lock connectors.</li>
		<li>Prepare a micro-pipette with a 20-200 &#181;l tip, set the volume to 100 &#181;l. This pipette tip format is adapted to the size of the sorbent column to be prepared. The procedure would be more difficult with larger pipette tips such as the ones used with 1 ml pipettes.</li>
		<li>Agitate the sorbent suspension with a vortex, and rapidly pipet 100 &#181;l in the center on the column. While injecting, aspirate gently all the pipetted solution trough the membrane by using the syringe with the other hand. At this stage, the solution filling the syringe must be clear of particles, and a particle bed can eventually be observed in the column.</li>
		<li>Repeat this process 2 more times by agitating the stock suspension between all pipetting steps to ensure homogeneous suspension of the particles in the solution. The resulting column contains 6 mg of sorbent.</li>
		<li>When the 300 &#181;l of suspension have been loaded and dried by aspirating with the syringe, keep the syringe in position and place the second Nylon membrane on the top by using the forceps with the other hand.</li>
		<li>Screw down the second connector with tube and dispose the syringe. The SPE column is ready for use.</li>
	</ol>
	</li>
</ol>
3. Preparing the System
<ol>
	<li>Tighten the SPE column on the device by using the Luer-Lock connectors. The arrow must be pointing to the same direction as the one shown on the device.</li>
	<li>Connect the bottle containing the sample to the device by screwing the provided GL45 safety cap on it.</li>
	<li>Load 200 &#181;l of eluent in the &#39;Eluent&#39; reservoir.</li>
	<li>Load 800 &#181;l of di-water in the &#39;Dilution&#39; reservoir.</li>
	<li>Place a bottle at the waste outlet to collect the processed water during extraction step. The format is not important but the volume needs to be sufficiently large with regard to the sample volume.</li>
	<li>Place a small vial at the sensor outlet with the minimum volume capacity of 1.5 ml. A maximum volume of 1 ml will be too small as bubbles will form at this outlet when collecting enriched eluent and dilution buffer.</li>
	<li>Verify the pressure regulator is in closed position by turning it manually, reverse-clockwise until further movement is not possible.</li>
</ol>
4. SPE with the Prototype
<ol>
	<li>Switch on the prototype by pressing the button on the back.</li>
	<li>Preparing the user interface and selecting the program
	<ol>
		<li>Open the user interface. Select the communication port of the computer to which the device is connected from the list, and click the button &#39;Next&#39;.</li>
		<li>Enter the values 580 for pset and 30 for dpset. The pump will adjust to maintain pressure in the pressurized system and reservoirs at 580 &#177; 30 mbar when running.</li>
		<li>Select the automated mode.</li>
		<li>In the automated mode corner, load the program file in the box &#39;configuration file path&#39;.</li>
	</ol>
	</li>
	<li>Adjusting the pressure regulator
	<ol>
		<li>Start the pump.</li>
		<li>Turn manually the pressure regulator until the value read for preg is inferior but close to 320 mbar.</li>
		<li>Stop the pump.</li>
	</ol>
	</li>
	<li>Starting the SPE procedure
	<ol>
		<li>Press &#39;start&#39; in the automated mode corner. The pump will switch on and the extraction, elution and dilution steps will automatically follow one another. The whole procedure for a 100 ml sample is performed in 50 min.</li>
		<li>Verify the value of preg. It must be in the range 320 - 350 mbar during the extraction step to ensure an optimal flow-rate.</li>
		<li>Close the small vial and store at 4-5 &#176;C in the dark until analysis. Perform analysis in the following 30 hr to prevent degradation of the analyte.</li>
		<li>Dispose of the processed water.</li>
	</ol>
	</li>
	<li>Cleaning the system 
	Note: After each extraction procedure the system needs to be cleaned to prevent cross-contamination.
	<ol>
		<li>Prepare a 10 ml solution of methanol 70% v/v in a GL 45 glass bottle.</li>
		<li>Unplug the SPE column and plug the tubing with connectors.</li>
		<li>In the automated mode, select the &#39;cleaning&#39; file and start it with same pressure settings.</li>
	</ol>
	</li>
</ol>
5. Detection of Estradiol Concentration with ELISA
<ol>
	<li>Prepare the calibration samples with concentrations as indicated in the protocol provided with the ELISA kit that is used. Prepare one calibration set with the same matrix as the sample, and one calibration set with methanol 10% v/v.</li>
	<li>Dispense the necessary amount of sample in the wells on the plate, according to manufacturer&#39;s instructions. Use calibration samples, unmodified and spiked water samples that were filtered but not processed with SPE, and enriched samples in methanol 10% v/v. Use 3 wells per sample to reduce the error associated with the assay.</li>
	<li>Follow the indications of the protocol that is provided with the kit for the addition of reactants, incubation time, washing and further reaction with the enzyme.</li>
	<li>Read the optical signal in each well according to the kit manufacturer&#39;s instructions with a plate reader instrument and collect the data.</li>
	<li>Use the software of the plate reader instrument to fit the calibration curves and determine the E2 concentration in the initial sample with same matrix, and in the enriched samples with methanol 10% v/v.</li>
</ol>

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The authors have nothing to disclose.

A new method for the preparation of water samples followed by analysis using immunoassay was proposed. The instrument enables to perform solid phase extraction in an automated and user-friendly way.
The filtration of the water sample prior to its injection into the system is critical. Any particulates still present in the solution would potentially cause clogging of the fluidic network and obstruct the SPE column. Another important step is the preparation of the SPE column. The amount of parti...

Sample preparation is an important step in any analytical process. In particular, removal of matrix effects, diminution of interferences, and enrichment of the analyte are necessary to obtain precise results and reach low limits of detection. Endocrine disrupting compounds (EDCs) are of particular concern due to their action on the living organisms even when present at very low levels in the environment. The natural hormone 17&#946;-estradiol is present on the EU water pollution Watch List and prone to be added to the list of priority substances regulated under the European Water Framework Directive. Solid phase extraction (SPE) is commonly applied for the analysis of small pollutants in water, with both chemical 1-5 (chromatography, mass spectrometry) and immunological 6-9 detection methods. The latter gained interest in the field of environmental monitoring, as immunoassays are available in large variety of formats, are specific to the target analyte, and reach low limits of detection.6, 7, 10, 11 Various enzyme linked immunosorbent assays (ELISA) are commercially available and enable to analyze multiple samples at once on a multi-well plate. The procedure consists in successive reaction steps that can take a few hours. The final product of reaction can be detected optically to determine the concentration of the target molecule based on a calibration curve.
Classical SPE procedures include sorbent pre-conditioning, sample extraction, washing, elution, and concentration by evaporation of the eluent. The solvent used for dilution of this extract is chosen depending on the detection method. For immunological methods, the amount of organic solvent influences strongly the sensitivity of the method.12
In addition to the recovery and the pre-concentration performances, the method also needs to be simple and cost efficient. Automation of the procedure helps to reduce human-related errors. In our previous work 13 we introduced our prototype for automated SPE, and our method was applied to the analysis of the natural hormone 17&#946;-estradiol in sea water samples. With the present video we would like to highlight the technical advantages of our method compared to traditional off-line and on-line SPE, and its particular compatibility with detection by immuno-reactions. We describe the protocol applied to water samples for the detection of 17&#946;-estradiol. SPE is performed with octadecyl-silica (C18) sorbent phase and elution is performed with diluted methanol.

<table border="0" cellpadding="0" cellspacing="0" width="609">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Filter membrane 0.2 &#956;m pore size</td>
			<td style="width:107px;">Merck Millipore</td>
			<td style="width:119px;">GNWP04700</td>
			<td style="width:167px;">For sample filtration</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Nylon membrane 11 &#956;m pore size</td>
			<td style="width:107px;">Merck Millipore</td>
			<td style="width:119px;">NY1104700</td>
			<td>For SPE column</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Disposable biopsy punch 5 mm</td>
			<td style="width:107px;">Medical Budget</td>
			<td style="width:119px;">39302439</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Nucleodur C18 ec&#160;</td>
			<td style="width:107px;">Macherey Nagel</td>
			<td style="width:119px;">713550.01</td>
			<td>50 &#956;m particle diameter</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Synthetic sea water</td>
			<td style="width:107px;">Sigma Aldrich</td>
			<td style="width:119px;">SSWS500-500ML</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Methanol</td>
			<td style="width:107px;">VWR</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">17beta-estradiol standard</td>
			<td style="width:107px;">Enzo Life Science</td>
			<td style="width:119px;"></td>
			<td>300 ng/ml</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">17beta-estradiol ELISA kit&#160;</td>
			<td style="width:107px;">Enzo Life Science</td>
			<td style="width:119px;">ADI-900-008</td>
			<td>96 wells, range 30 - 3000 ng/L</td>
		</tr>
	</tbody>
</table>

a simple method for automated solid phase extraction of water samples for immunological analysis of small pollutants

A new method for solid phase extraction (SPE) of environmental water samples is proposed. The developed prototype is cost-efficient and user friendly, and enables to perform rapid, automated and simple SPE. The pre-concentrated solution is compatible with analysis by immunoassay, with a low organic solvent content. A method is described for the extraction and pre-concentration of natural hormone 17&#946;-estradiol in 100 ml water samples. Reverse phase SPE is performed with octadecyl-silica sorbent and elution is done with 200 &#181;l of methanol 50% v/v. Eluent is diluted by adding di-water to lower the amount of methanol. After preparing manually the SPE column, the overall procedure is performed automatically within 1 hr. At the end of the process, estradiol concentration is measured by using a commercial enzyme-linked immune-sorbent assay (ELISA). 100-fold pre-concentration is achieved and the methanol content in only 10% v/v. Full recoveries of the molecule are achieved with 1 ng/L spiked de-ionized and synthetic sea water samples.

Reproducibility of sorbent packing was evaluated by drying and weighting the pipetted sorbent in glass vials and the result is shown in Figure 1. Reproducibility of the time of injection was tested for 100 ml samples, as shown in Figure 2. Concentration in initial and pre-concentrated spiked samples were determined by using a commercial ELISA kit for 17&#946;-estradiol and are shown in Figure 3.
<p class="jove_content" fo:keep-togethe...

Watch this Scientific Journal Video about A Simple Method for Automated Solid Phase Extraction of Water Samples for Immunological Analysis of Small Pollutants at JoVE.com

A Simple Method for Automated Solid Phase Extraction of Water Samples for Immunological Analysis of Small Pollutants

A protocol for the extraction and pre-concentration of estradiol from water samples by using an automated and miniaturized system is presented.

A new method for solid phase extraction (SPE) of environmental water samples is proposed. The developed prototype is cost-efficient and user friendly, and ...

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13.6K Views.  Centre Suisse d'Electronique et de Microtechnique. A protocol for the extraction and pre-concentration of estradiol from water samples by using an automated and miniaturized system is presented.

Video: A Simple Method for Automated Solid Phase Extraction of Water Samples for Immunological Analysis of Small Pollutants

A Small Volume Procedure for Viral Concentration from Water

Small-scale concentration of viruses (sample volumes 1-10 L, here simulated with spiked 100 ml water samples) is an efficient, cost-effective way to identify optimal parameters for virus concentration. Viruses can be concentrated from water using filtration (electropositive, electronegative, glass wool or size exclusion), followed by secondary concentration with beef extract to release viruses from filter surfaces, and finally tertiary concentration resulting in a 5-30 ml volume virus concentrate. In order to identify optimal concentration procedures, two different electropositive filters were evaluated (a glass/cellulose filter [1MDS] and a nano-alumina/glass filter [NanoCeram]), as well as different secondary concentration techniques; the celite technique where three different celite particle sizes were evaluated (fine, medium and large) followed by comparing this technique with that of the established organic flocculation method. Various elution additives were also evaluated for their ability to enhance the release of adenovirus (AdV) particles from filter surfaces. Fine particle celite recovered similar levels of AdV40 and 41 to that of the established organic flocculation method when viral spikes were added during secondary concentration. The glass/cellulose filter recovered higher levels of both, AdV40 and 41, compared to that of a nano-alumina/glass fiber filter. Although not statistically significant, the addition of 0.1% sodium polyphosphate amended beef extract eluant recovered 10% more AdV particles compared to unamended beef extract.

An approach was developed for identifying optimal viral concentration conditions for small volume water samples using spikes of human adenovirus. The techniques described here are used to identify concentration parameters for other viral targets, and applied to large-scale viral concentration experimentation.

Small-scale concentration of viruses (sample volumes 1-10 L, here simulated with spiked 100 ml water samples) is an efficient, cost-effective way to ...

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. I. Collection of Virus Samples

EPA Method 1615 was developed with a goal of providing a standard method for measuring enteroviruses and noroviruses in environmental and drinking waters. The standardized sampling component of the method concentrates viruses that may be present in water by passage of a minimum specified volume of water through an electropositive cartridge filter. The minimum specified volumes for surface and finished/ground water are 300 L and 1,500 L, respectively. A major method limitation is the tendency for the filters to clog before meeting the sample volume requirement. Studies using two different, but equivalent, cartridge filter options showed that filter clogging was a problem with 10% of the samples with one of the filter types compared to 6% with the other filter type. Clogging tends to increase with turbidity, but cannot be predicted based on turbidity measurements only. From a cost standpoint one of the filter options is preferable over the other, but the water quality and experience with the water system to be sampled should be taken into consideration in making filter selections.

EPA Method 1615 uses an electropositive filter to concentrate enteroviruses and noroviruses in environmental and drinking waters. This manuscript describes the procedure for collecting samples for Method 1615 analyses.

EPA Method 1615 was developed with a goal of providing a standard method for measuring enteroviruses and noroviruses in environmental and drinking waters. ...

Use of Chironomidae (Diptera) Surface-Floating Pupal Exuviae as a Rapid Bioassessment Protocol for Water Bodies

Rapid bioassessment protocols using benthic macroinvertebrate assemblages have been successfully used to assess human impacts on water quality. Unfortunately, traditional benthic larval sampling methods, such as the dip-net, can be time-consuming and expensive. An alternative protocol involves collection of Chironomidae surface-floating pupal exuviae (SFPE). Chironomidae is a species-rich family of flies (Diptera) whose immature stages typically occur in aquatic habitats. Adult chironomids emerge from the water, leaving their pupal skins, or exuviae, floating on the water&#8217;s surface. Exuviae often accumulate along banks or behind obstructions by action of the wind or water current, where they can be collected to assess chironomid diversity and richness. Chironomids can be used as important biological indicators, since some species are more tolerant to pollution than others. Therefore, the relative abundance and species composition of collected SFPE reflect changes in water quality. Here, methods associated with field collection, laboratory processing, slide mounting, and identification of chironomid SFPE are described in detail. Advantages of the SFPE method include minimal disturbance at a sampling area, efficient and economical sample collection and laboratory processing, ease of identification, applicability in nearly all aquatic environments, and a potentially more sensitive measure of ecosystem stress. Limitations include the inability to determine larval microhabitat use and inability to identify pupal exuviae to species if they have not been associated with adult males.

Use of Chironomidae Diptera Surface-Floating Pupal Exuviae as a Rapid Bioassessment Protocol for Water Bodies

Rapid bioassessment protocols using benthic macroinvertebrates are often used to monitor and assess water quality. An efficient protocol involves collections of Chironomidae surface-floating pupal exuviae (SFPE). Here, techniques for field collection, laboratory processing, slide mounting, and identification of Chironomidae SFPE are described.

Rapid bioassessment protocols using benthic macroinvertebrate assemblages have been successfully used to assess human impacts on water quality. ...

Automated Gel Size Selection to Improve the Quality of Next-generation Sequencing Libraries Prepared from Environmental Water Samples

Next-generation sequencing of environmental samples can be challenging because of the variable DNA quantity and quality in these samples. High quality DNA libraries are needed for optimal results from next-generation sequencing. Environmental samples such as water may have low quality and quantities of DNA as well as contaminants that co-precipitate with DNA. The mechanical and enzymatic processes involved in extraction and library preparation may further damage the DNA. Gel size selection enables purification and recovery of DNA fragments of a defined size for sequencing applications. Nevertheless, this task is one of the most time-consuming steps in the DNA library preparation workflow. The protocol described here enables complete automation of agarose gel loading, electrophoretic analysis, and recovery of targeted DNA fragments. 
In this study, we describe a high-throughput approach to prepare high quality DNA libraries from freshwater samples that can be applied also to other environmental samples. We used an indirect approach to concentrate bacterial cells from environmental freshwater samples; DNA was extracted using a commercially available DNA extraction kit, and DNA libraries were prepared using a commercial transposon-based protocol. DNA fragments of 500 to 800 bp were gel size selected using Ranger Technology, an automated electrophoresis workstation. Sequencing of the size-selected DNA libraries demonstrated significant improvements to read length and quality of the sequencing reads.

This manuscript describes an automated gel size selection approach for purifying DNA fragments for next-generation sequencing. The Ranger Technology provides complete automation of the entire process of agarose gel loading, electrophoretic analysis, and recovery of targeted DNA fragments allowing for high-throughput and high quality next-generation sequencing libraries.

Next-generation sequencing of environmental samples can be challenging because of the variable DNA quantity and quality in these samples. High quality DNA ...

Use of a Filter Cartridge for Filtration of Water Samples and Extraction of Environmental DNA

Recent studies demonstrated the use of environmental DNA (eDNA) from fishes to be appropriate as a non-invasive monitoring tool. Most of these studies employed disk fiber filters to collect eDNA from water samples, although a number of microbial studies in aquatic environments have employed filter cartridges, because the cartridge has the advantage of accommodating large water volumes and of overall ease of use. Here we provide a protocol for filtration of water samples using the filter cartridge and extraction of eDNA from the filter without having to cut open the housing. The main portions of this protocol consists of 1) filtration of water samples (water volumes &#8804;4 L or &gt;4 L); (2) extraction of DNA on the filter using a roller shaker placed in a preheated incubator; and (3) purification of DNA using a commercial kit. With the use of this and previously-used protocols, we perform metabarcoding analysis of eDNA taken from a huge aquarium tank (7,500 m3) with known species composition, and show the number of detected species per library from the two protocols as the representative results. This protocol has been developed for metabarcoding eDNA from fishes, but is also applicable to eDNA from other organisms.

We describe a protocol for filtration of water samples with a filter cartridge and extraction of environmental DNA (eDNA) without having to cut open the housing to remove the filter. This protocol is developed for metabarcoding eDNA from fishes, but is also applicable to eDNA from other organisms.

Recent studies demonstrated the use of environmental DNA (eDNA) from fishes to be appropriate as a non-invasive monitoring tool. Most of these studies ...

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.

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.

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

Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type Analysis

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment during manufacturing and transport. Because of their environmental persistence, they are widely distributed in the oceans and on beaches all over the world. They can act as a vector of potentially toxic organic compounds (e.g., polychlorinated biphenyls) and might consequently negatively affect marine organisms. Their possible impacts along the food chain are not yet well understood. In order to assess the hazards associated with the occurrence of plastic pellets in the marine environment, it is necessary to develop methodologies that allow for rapid determination of associated organic contaminant levels. The present protocol describes the different steps required for sampling resin pellets, analyzing adsorbed organochlorine pesticides (OCPs) and identifying the plastic type. The focus is on the extraction of OCPs from plastic pellets by means of a pressurized fluid extractor (PFE) and on the polymer chemical analysis applying Fourier Transform-InfraRed (FT-IR) spectroscopy. The developed methodology focuses on 11 OCPs and related compounds, including dichlorodiphenyltrichloroethane (DDT) and its two main metabolites, lindane and two production isomers, as well as the two biologically active isomers of technical endosulfan. This protocol constitutes a simple and rapid alternative to existing methodology for evaluating the concentration of organic contaminants adsorbed on plastic pieces.

Microplastics act as vector of potentially toxic organic contaminants with unpredictable effects. This protocol describes an alternative methodology for assessing the levels of organochlorine pesticides adsorbed on plastic pellets and identifying the polymer chemical structure. The focus is on pressurized fluid extraction and attenuated total reflectance Fourier transform infrared spectroscopy.

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment ...

A Simple Planting Technique for Re-establishing Trees Where Frequent Inundation Occurs

Many of the Everglades tree islands have lost elevation over the past century and most of their trees have died such that they are now covered with herbaceous plants. This protocol describes a simple, cost-effective tree planting technique needed for restoring degraded Everglade tree islands. The design is patterned after a natural Everglades process that creates floating peat islands, which allows tree survival and growth in flooded conditions and often leads to the development of tree islands. Commercially available peat bags were used as the medium for the growth and establishment of potted native tree saplings. The pop-up configuration floated initially and provided additional elevation to minimize inundation, with a single native tree species sapling and a single tree fertilizer spike. During a 3 year study involving 105 pop-ups, most plants survived (80%) and many thrived. Determining whether this technique can establish trees on a degraded tree island will require longer studies and extensive field tests.

This protocol describes a simple, cost-effective tree planting technique for restoring degraded Everglades tree islands that experience inundation. The design creates an island (pop-up) which floats initially and adds elevation to promote tree survival and growth under flooded conditions.

Many of the Everglades tree islands have lost elevation over the past century and most of their trees have died such that they are now covered with ...

Collection and Extraction of Occupational Air Samples for Analysis of Fungal DNA

Traditional methods of identifying fungal exposures in occupational environments, such as culture and microscopy-based approaches, have several limitations that have resulted in the exclusion of many species. Advances in the field over the last two decades have led occupational health researchers to turn to molecular-based approaches for identifying fungal hazards. These methods have resulted in the detection of many species within indoor and occupational environments that have not been detected using traditional methods. This protocol details an approach for determining fungal diversity within air samples through genomic DNA extraction, amplification, sequencing, and taxonomic identification of fungal internal transcribed spacer (ITS) regions. ITS sequencing results in the detection of many fungal species that are either not detected or difficult to identify to species level using culture or microscopy. While these methods do not provide quantitative measures of fungal burden, they offer a new approach to hazard identification and can be used to determine overall species richness and diversity within an occupational environment.

Determining the fungal diversity within an environment is a method utilized in occupational health studies to identify health hazards. This protocol describes DNA extraction from occupational air samples for amplification and sequencing of fungal ITS regions. This approach detects many fungal species that can be overlooked by traditional assessment methods.