Name: characterization and application of passive samplers for monitoring of pesticides in water
Uploaded: 2016-08-03T09:00:00
Description: Watch this Scientific Journal Video about Characterization and Application of Passive Samplers for Monitoring of Pesticides in Water at JoVE.com

The Swedish EPA (Naturv&#229;rdsverket) (agreement 2208-13-001) and Centre for Chemical Pesticides (CKB) are gratefully acknowledged for funding this project. We thank M&#228;rit Peterson, Henrik Jernstedt, Emma Gurnell and Elin Paulsson at the OMK-lab, SLU, for skillful assistance with analytical support and supply of pesticide standards.

1. Passive Sampler Design and Preparation
<ol>
	<li>Silicone rubber sheets
	<ol>
		<li>Cut the silicone rubber sheets (600 mm x 600 mm, 0.5 mm thick) into stripes of 2.5 mm x 600 mm and 2.5 mm x 314 mm using a stainless steel cutter and connect them using a stainless steel blind rivet (3.2 mm x 10 mm) with a rivet gun to obtain a total sampler stripe size of 2.5 mm x 914 mm (surface area = 457 cm2, sorbent mass = 15.6 g, volume = 22.9 cm3).</li>
	</ol>
	</li>
	<li>Place the silico...

<ol>
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Chem. 23 (7), 1640-1648 (2004).</li><li>Vrana, B., 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=Passive+sampling:+An+effective+method+for+monitoring+seasonal+and+spatial+variability+of+dissolved+hydrophobic+organic+contaminants+and+metals+in+the+Danube+river.">Passive sampling: An effective method for monitoring seasonal and spatial variability of dissolved hydrophobic organic contaminants and metals in the Danube river.</a> Environ. Pollut. 184, 101-112 (2014).</li><li>Dougherty, J. A., Swarzenski, P. W., Dinicola, R. 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A. 1218 (51), 9162-9173 (2011).</li><li>Poulier, G., 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=Estimates+of+pesticide+concentrations+and+fluxes+in+two+rivers+of+an+extensive+French+multi-agricultural+watershed:+application+of+the+passive+sampling+strategy.">Estimates of pesticide concentrations and fluxes in two rivers of an extensive French multi-agricultural watershed: application of the passive sampling strategy.</a> Environ. Sci. Pollut. Res. 22 (11), 8044-8057 (2015).</li><li>Moschet, C., Vermeirssen, E. L. 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Technol. 43 (14), 5383-5390 (2009).</li><li>Vrana, B., 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=Passive+sampling+techniques+for+monitoring+pollutants+in+water.">Passive sampling techniques for monitoring pollutants in water.</a> TrAC - Trend. Anal. Chem. 24 (10), 845-868 (2005).</li><li>Allan, I. J., Harman, C., Ranneklev, S. B., Thomas, K. V., Grung, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Passive+sampling+for+target+and+nontarget+analyses+of+moderately+polar+and+nonpolar+substances+in+water.">Passive sampling for target and nontarget analyses of moderately polar and nonpolar substances in water.</a> Environ. Toxicol. Chem. 32 (8), 1718-1726 (2013).</li><li>Escher, B. I., 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=Evaluation+of+contaminant+removal+of+reverse+osmosis+and+advanced+oxidation+in+full-scale+operation+by+combining+passive+sampling+with+chemical+analysis+and+bioanalytical+tools.">Evaluation of contaminant removal of reverse osmosis and advanced oxidation in full-scale operation by combining passive sampling with chemical analysis and bioanalytical tools.</a> Environ. Sci. Technol. 45, 5387-5394 (2011).</li><li>Pesce, S., Morin, S., Lissalde, S., Montuelle, B., Mazzella, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Combining+polar+organic+chemical+integrative+samplers+(POCIS)+with+toxicity+testing+to+evaluate+pesticide+mixture+effects+on+natural+phototrophic+biofilms.">Combining polar organic chemical integrative samplers (POCIS) with toxicity testing to evaluate pesticide mixture effects on natural phototrophic biofilms.</a> Environ. Pollut. 159 (3), 735-741 (2011).</li><li>Booij, K., Smedes, F., Van Weerlee, E. M., Honkoop, P. J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Environmental+monitoring+of+hydrophobic+organic+contaminants:+The+case+of+mussels+versus+semipermeable+membrane+devices.">Environmental monitoring of hydrophobic organic contaminants: The case of mussels versus semipermeable membrane devices.</a> Environ. Sci. Technol. 40 (12), 3893-3900 (2006).</li><li>Harman, C., Allan, I. J., Vermeirssen, E. L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calibration+and+use+of+the+polar+organic+chemical+integrative+sampler-a+critical+review.">Calibration and use of the polar organic chemical integrative sampler-a critical review.</a> Environ. Toxicol. Chem. 31 (12), 2724-2738 (2012).</li><li>Jonker, M. T. O., Der Heijden, S. A. V. a. n., Kotte, M., Smedes, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantifying+the+effects+of+temperature+and+salinity+on+partitioning+of+hydrophobic+organic+chemicals+to+silicone+rubber+passive+samplers.">Quantifying the effects of temperature and salinity on partitioning of hydrophobic organic chemicals to silicone rubber passive samplers.</a> Environ. Sci. Technol. 49 (11), 6791-6799 (2015).</li><li>Jansson, C., Kreuger, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiresidue+analysis+of+95+pesticides+at+low+nanogram/liter+levels+in+surface+waters+using+online+preconcentration+and+high+performance+liquid+chromatography/tandem+mass+spectrometry.">Multiresidue analysis of 95 pesticides at low nanogram/liter levels in surface waters using online preconcentration and high performance liquid chromatography/tandem mass spectrometry.</a> J. AOAC Int. 93 (6), 1732-1747 (2010).</li><li>Ahrens, L., Daneshvar, A., Lau, A. E., Kreuger, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+five+passive+sampling+devices+for+monitoring+of+pesticides+in+water.">Characterization of five passive sampling devices for monitoring of pesticides in water.</a> J. Chromatogr. A. 1405, 1-11 (2015).</li><li>Royston, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Approximating+the+Shapiro-Wilk+W-test+for+non-normality.">Approximating the Shapiro-Wilk W-test for non-normality.</a> Stat. Comput. 2 (3), 117-119 (1992).</li><li>Gauthier, T. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detecting+trends+using+Spearman's+rank+correlation+coefficient.">Detecting trends using Spearman's rank correlation coefficient.</a> Environ. Forensics. 2 (4), 359-362 (2001).</li><li>Morin, N., Mi&#232;ge, C., Coquery, M., Randon, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemical+calibration,+performance,+validation+and+applications+of+the+polar+organic+chemical+integrative+sampler+(POCIS)+in+aquatic+environments.">Chemical calibration, performance, validation and applications of the polar organic chemical integrative sampler (POCIS) in aquatic environments.</a> TrAC - Trend. Anal. Chem. 36, 144-175 (2012).</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=Water+Quality+-+Sampling+-+Part+23:+Guidance+on+Passive+Sampling+in+Surface+Waters.">Water Quality - Sampling - Part 23: Guidance on Passive Sampling in Surface Waters.</a> ISO 5667-23:2011. , (2011).</li><li>Morin, N., Camilleri, J., Cren-Oliv&#233;, C., Coquery, M., Mi&#232;ge, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+uptake+kinetics+and+sampling+rates+for+56+organic+micropollutants+using+"pharmaceutical"+POCIS.">Determination of uptake kinetics and sampling rates for 56 organic micropollutants using "pharmaceutical" POCIS.</a> Talanta. 109, 61-73 (2013).</li></ol>

For quality control, as standard procedure, laboratory blanks, limits of detection (LOD), recoveries, and repeatability were examined23. A few pesticides were detected in the blank samples at low concentration levels. LODs were set as the value of the lowest point on the calibration curve which meets the criteria of a signal to noise ratio of 3. The average LODs were 8.0 pg absolute injected on column for silicone rubber, 1.7 pg absolute for POCIS-A, 1.6 pg absolute for POCIS-B, 3.0 pg absolute for SDB-RPS dis...

Pesticides are continuously introduced to the aquatic environment and may pose a risk to aquatic organisms1. Monitoring of pesticides in the aqueous environment is typically performed using grab sampling, however, this sampling technique does not fully account for temporal variations in concentrations due to fluctuations in flow or episodic inputs (e.g., precipitation, combined sewer overflows, sewage lagoon release)2,3. Thus, monitoring methods need to be improved for a better estimation of environmental risks associated with pesticides. Passive sampling allows continuous monitoring over an extended period of time with minimal infrastructure and low contaminant concentrations4,5.
Passive samplers have been shown to be a valuable tool for the monitoring in groundwater6, fresh water7-10, wastewater11 and marine waters12. Besides monitoring purposes13,14, passive samplers have also been used for non-target analysis15, toxicology testing16,17, and as an alternative to sediment- and biomonitoring18. Passive samplers accumulate chemicals continuously from water and provide time weighted average (TWA) concentrations14. The uptake of the contaminant depends on the sampling rate (RS) and passive sampler-water partition coefficient (KPW), which depends on the passive sampler design, sampler material, physicochemical properties of the contaminant, and environmental conditions (e.g., water turbulence, temperature)13,14,19,20.
The detailed video aims to show how to calibrate and apply passive samplers for pesticides in water. The specific objectives included i) to perform preparation, extraction and instrumental analysis for 124 individual pesticides using five different types of passive samplers, including silicone rubber, polar organic chemical integrative sampler (POCIS)-A, POCIS-B, SDB-RPS and C18 disk, ii) to assess RS and KPW for the pesticides in a laboratory uptake study, and iii) to demonstrate how to select the appropriate passive sampler of the target compound of interest and how to calculate TWA concentrations for the respective passive sampler.
Reference standards and passive sampler devices
Target compounds included 124 legacy and currently used pesticides including herbicides, insecticides and fungicides (Table 1). Internal standard mixture (IS mixture) included fenoprop (2,4,5-TP), clothianidin-D3, ethion and terbuthylazine-D5. Other used chemicals included methanol (MeOH), acetonitrile (ACN), acetone (ACE), dichloromethane (DCM), cyclohexane (CH), ethyl acetate (EA), petroleum ether (PE), 2-propanol, 25% ammonia solution, acetic acid (HAc) and formic acid (FA). Five different passive sampling devices were characterized, including silicone rubber, POCIS-A and POCIS-B, SDB-RPS, and C18 disk1,21.
Table 1. Passive sampler sampling rate (R&#39;S, L day-1), sampler-water partition coefficients (K&#39;PW, L kg-1) and equations (Eq.) used for the calculation of concentrations in field samples for individual pesticidesa. (Reprinted from Journal of Chromatography A, 1405, Lutz Ahrens, Atlasi Daneshvar, Anna E. Lau, Jenny Kreuger, Characterization of five passive sampling devices for monitoring of pesticides in water, 1-11, Copyright (2015), with permission from Elsevier.)22 <a href="https://www.jove.com/files/ftp_upload/54053/Table_1.xlsx" target="_blank">Please click here to download this file.</a>

<table border="0" cellpadding="0" cellspacing="0" width="1047">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Methanol</td>
			<td style="width:164px;">Merck Millipore</td>
			<td style="width:163px;">1.06035.2500</td>
			<td style="width:228px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Acetonitrile</td>
			<td>Merck Millipore</td>
			<td>1.00029.2500&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:22px;width:492px;">Acetone</td>
			<td>Merck Millipore</td>
			<td style="width:163px;">1.00012.2500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2-propanol</td>
			<td>Merck Millipore</td>
			<td>1.00272.2500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Dichloromethane</td>
			<td>Merck Millipore</td>
			<td>1.06054.2500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ammoniak</td>
			<td>Merck Millipore</td>
			<td>1.05428.1000</td>
			<td>Purity 25%</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Formic acid</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td>94318-50ML-F</td>
			<td>Purity ~98%</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:22px;">Ethyl acetate&#160;</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td>31063-2.5L</td>
			<td>for pesticide residue analysis</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:22px;">Petroleum ether&#160;</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td>34491-4X2.5L</td>
			<td>for pesticide residue analysis</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Acetic acid&#160;</td>
			<td style="width:164px;">Sigma-Aldrich</td>
			<td>320099-500ML</td>
			<td>Purity &#8805;99.7%</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cyclohexane&#160;</td>
			<td style="width:164px;">Fisher Chemicals</td>
			<td>C/8933/17</td>
			<td>for residue analysis</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Empty polypropylene SPE Tube with PE frits, 20 &#956;m porosity, volume 6&#160;mL</td>
			<td style="width:164px;">Supelco</td>
			<td>57026</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Empore SPE Disks, C18, diam. 47&#160;mm</td>
			<td>Supelco</td>
			<td style="width:163px;">66883-U</td>
			<td>Passive sampler</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Empore SPE Disks, SDB-RPS (Reversed-Phase Sulfonate), diam. 47&#160;mm</td>
			<td>Supelco</td>
			<td style="width:163px;">66886-U&#160;</td>
			<td>Passive sampler</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">POCIS-A&#160;</td>
			<td>EST</td>
			<td style="width:163px;">POCIS-HLB</td>
			<td>Passive sampler</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">POCIS-B</td>
			<td>EST</td>
			<td style="width:163px;">POCIS-Pesticide&#160;</td>
			<td>Passive sampler</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Polyethersulfone (PES) membranes</td>
			<td>EST</td>
			<td style="width:163px;">PES</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Silicone rubber sheet</td>
			<td style="width:164px;">Altec</td>
			<td style="width:163px;">03-65-4516</td>
			<td>Passive sampler</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Agilent 5975C</td>
			<td style="width:164px;">Agilent Technologies</td>
			<td style="width:163px;">5975C</td>
			<td>GC-MS</td>
		</tr>
		<tr height="23">
			<td height="23" style="height:23px;width:492px;">HP-5MS UI</td>
			<td style="width:164px;">J&#38;W Scientific</td>
			<td style="width:163px;">HP-5MS</td>
			<td>Analytical column for GC-MS</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Agilent 6460</td>
			<td style="width:164px;">Agilent Technologies</td>
			<td style="width:163px;">6460</td>
			<td>HPLC-MS/MS</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Strata C18&#8211;E, 20 x 2 mm id and 20&#8211;25 &#956;m particle size</td>
			<td style="width:164px;">Phenomenex</td>
			<td style="width:163px;">Strata C18&#8211;E</td>
			<td style="width:228px;">Online SPE column for LC-MS/MS</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Strata X, 20 x 2 mm id and 20&#8211;25 &#956;m particle size</td>
			<td style="width:164px;">Phenomenex</td>
			<td style="width:163px;">Strata X</td>
			<td style="width:228px;">Online SPE column for LC-MS/MS</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:492px;">Zorbax Eclipse Plus C18</td>
			<td style="width:164px;">Agilent Technologies</td>
			<td style="width:163px;">Zorbax Eclipse Plus C18</td>
			<td>Analytical column for LC-MS/MS</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Isolute phase separator, 25 mL</td>
			<td style="width:164px;">Biotage</td>
			<td style="width:163px;">120-1907-E</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:492px;">Stainless steel blind rivet, 3.2x10 mm</td>
			<td style="width:164px;">Ejot &#38; Avdel</td>
			<td style="width:163px;">951222</td>
			<td></td>
		</tr>
	</tbody>
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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).

Five different passive sampler techniques were compared for the uptake of 124 legacy and current used pesticides including silicone rubber (Figure 1), and POCIS A, POCIS B, SDB-RPS and C18 disk (Figure 2). The performance of the extraction method and instrumental analysis was optimized. The outcome of the laboratory uptake experiments can be used to calculate the R&#39;S and log K&#39;PW values (T...

Watch this Scientific Journal Video about Characterization and Application of Passive Samplers for Monitoring of Pesticides in Water at JoVE.com

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

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

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

The overall goal of this procedure is to demonstrate preparation, extraction, and analysis of pesticides using five different passive sampling devices and to show how to calibrate them in the laboratory for field application. Passive sampling is a promising tool to answer quick questions for measuring pesticides, continuously at low concentration levels to improve for example, environmental risk assessments. The main advantage of passive sampling is that it's a simple time-integrated method for measuring a broad range of pesticides in aqueous environment.This method is a valuable tool for monitoring of pesticides in water. It can also be used for non-target analyzers, toxicity testing, and as an alternative for sediment and biomonitoring. Following this procedure, sampling rates and passive sampler water partitioning coefficients can be calculated based on the uptake profile for individual pesticides.Cut silicone rubber sheets into stripes of 2.5 millimeters by 600 millimeters and 2.5 millimeters by 214 millimeters using a stainless steel cutter. Connect them using a stainless steel blind rivet with a rivet gun to obtain a total sampler stripe size of 2.5 millimeters by 914 millimeters. After cleaning the silicone rubbers by socket extraction as described in the text protocol attach a silicone rubber stripe to a stainless steel spider sampler holder by wrapping the silicone rubber stripe around the rods on the holder.Attach each end of the silicone rubber stripe to a rod on the holder to the loop at the end of the silicone rubber stripe. For POCIS A place 220 milligrams of HLB bulk sorbent between 2 9.0 centimeters by 9.0 centimeters square PES membranes. For POCIS B, place 220 milligrams of a sorbent mixture between two PES membranes.Compress the sorbent and the two PES membranes between two stainless steel rings manually, and secure onto a stainless steel sample holder. Next, place the SDBRPC and C18 disks between two PES membranes. Similarly compress the disks and two PES membranes between two stainless steel rings manually and secure onto a stainless steel sample holder.Fill the three tanks with natural water. Perform all experiments at a constant water temperature and under turbulent water conditions using two electric pumps attached to the tank wall on each side. Also perform the experiments in the dark to minimize the effect of photo-degradation.Next spike each glass container with a pesticide standard mixture containing 124 pesticides using a glass syringe. Conduct the uptake study in rectangular 95 liter glass containers. Designate tank one for silicone rubber, tank two for POCIS A, POCIS B.And tank three for SDB-RPS disk C18 disk.Take out the passive samplers manually from the tanks at time intervals of 5, 11, 20, and 26 days to determine the sampling rates of the pesticides. In addition, monitor the concentrations of the pesticides in each tank by collecting 100 milliliter water samples at day 0, 5, 11, 20, and 26. Prior to extraction, dry the silicone rubber stripe under a stream of high purity nitrogen gas.For gas chromotography mass spectrometry analysis, carry out the solid liquid extraction using sockslet extraction. After placing the silicone rubber into the sockslet extractor add 250 milliliters petroleum ether and acetone and 3 boiling stones into the round bottom flask. Spike the silicone rubber with 100 microliters of an internal standard mixture using a pipet.Then add 50 milliliters of petroleum acetone into the sockslet extractor. Switch on the heater and run the sockslet extraction for 19 hours and then switch off the heater. Concentrate the extracts by rotory evaporation followed by gentle nitrogen blowdown to one milliliter.Exchange the solvent to 90 to 10 cyclohexane to acetone by adding 3 times 1 milliliter of cyclohexane acetone during the nitrogen blowdown to 1 milliliter. For liquid chromotography tandem mass spectrometry analysis the silicone rubber is extracted with 300 milliliters of methanol. Exchange the solvent to a acetonitrile by adding one milliliter of acetonitrile during the nitrogen blowdown to one milliliter.Open the POCIS sampler carefully and transfer the sorbent with ultra-pure water using a funnel into a pre-cleaned empty polypropylene solid face extraction cartridge containing two polyethylene frets. Dry the sorbent by vacuum to remove water. Prior to elution, spike the sorbent with 100 microliters of an internal standard mixture using a pipet.Elude the POCIS A and POCIS B cartridges using 1.5 milliliters of methanol followed by 8 milliliters of 80 to 20 dychloromethane to methanol for LCMSMS analysis. Concentrate the extracts to 1 milliliter by gentle nitrogen blowdown before exchanging the solvent to acetonitrile by adding 1 milliliter of acetonitrile during the nitrogen blowdown to 1 milliliter. For gas chromotography mass spectrometry analysis POCIS A and B is eluded using 5 milliliters of ethyl acetate and the solvent is exchanged to 90 to 10 cyclohexane to acetone by adding 3 times 1 milliliter of cyclohexane to acetone during the nitrogen blowdown to 1 milliliter.Transfer individual disks of SDB-RPS and C18 into a glass beaker and dry them under nitrogen gas. Spike the disks with 100 microliters of an internal standard mixture using a pipet. Sonicate the disks two times in a glass beaker at room temperature.First with five milliliters of ethyl acetate for ten minutes and then with three milliliters of ethyl acetate for ten minutes. Transfer both extracts into one glass tube before concentrating them to two milliliters by gentle nitrogen blowdown. Split the samples into two one millimeter fractions for GCMS and LCMSMS analysis.In one fraction concentrate the extracts to 0.5 milliliters by gentle nitrogen blowdown and then exchange the solvent to cyclohexane and acetone for GCMS analysis. For LCMSMS analysis concentrate the extracts to 0.5 milliliters by gentle nitrogen blowdown and exchange the solvent to acetonitrile. Shown here are exemplary results for the uptake of acetamiprid in silicone rubber in nanograms showing a linear uptake from day 0 to 20 and then a curvilinear uptake from day 20 to 26.This plot shows exemplary results for the uptake of dimethoate in silicone rubber in nanograms. Showing a linear uptake from day 0 to 10 and then an equilibrium after day 10. The five tested passive samplers were capable of accumulating pesticides with a wide range of different octenol water partition coefficients showing that silicone rubber is more suitable for hydrophobic compounds, whereas more polar compounds were better taken up by POCIS A, POCIS B, and SDB-RPS disk.After watching this video you should have a good understanding how to prepare, extract, and analysis pesticides using five different passive sampling devices and how to calibrate them in the laboratory. While attempting this procedure it's important to remember that this study was performed under static conditions while future uptake study should consider using follow-through exposure or in calibration. The usage of performance compounds, which are spiked to the passive sampler before deployment can be used to calculate n-zeto sampling rates and allow for more accurate estimates of time-rate average concentration.Please don't forget, working with organic solvents acets and basics can be extremely hazardous and precautions like lab coat, gloves, eye protection, should be taken while performing this procedure.

characterization-application-passive-samplers-for-monitoring

Research

JoVE Journal

Environment

Waste Water Derived Electroactive Microbial Biofilms: Growth, Maintenance, and Basic Characterization

The growth of anodic electroactive microbial biofilms from waste water inocula in a fed-batch reactor is demonstrated using a three-electrode setup controlled by a potentiostat. Thereby the use of potentiostats allows an exact adjustment of the electrode potential and ensures reproducible microbial culturing conditions. During growth the current production is monitored using chronoamperometry (CA). Based on these data the maximum current density (jmax) and the coulombic efficiency (CE) are discussed as measures for characterization of the bioelectrocatalytic performance. Cyclic voltammetry (CV), a nondestructive, i.e. noninvasive, method, is used to study the extracellular electron transfer (EET) of electroactive bacteria. CV measurements are performed on anodic biofilm electrodes in the presence of the microbial substrate, i.e. turnover conditions, and in the absence of the substrate, i.e. nonturnover conditions, using different scan rates. Subsequently, data analysis is exemplified and fundamental thermodynamic parameters of the microbial EET are derived and explained: peak potential (Ep), peak current density (jp), formal potential (Ef) and peak separation (&#916;Ep). Additionally the limits of the method and the state-of the art data analysis are addressed. Thereby this video-article shall provide a guide for the basic experimental steps and the fundamental data analysis.

Chronoamperometric growth of anodic electroactive microbial biofilms in a fed-batch reactor using a three-electrode setup, controlled by a potentiostat, is demonstrated. The extracellular electron transfer is characterized using cyclic voltammetry in the presence of the electron donor and in the absence of the electron donor. Fundamental data analysis is demonstrated.

The growth of anodic electroactive microbial biofilms from waste water inocula in a fed-batch reactor is demonstrated using a three-electrode setup ...

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. ...

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. Part III. Virus Detection by RT-qPCR

EPA Method 1615 measures enteroviruses and noroviruses present in environmental and drinking waters. This method was developed with the goal of having a standardized method for use in multiple analytical laboratories during monitoring period 3 of the Unregulated Contaminant Monitoring Rule. Herein we present the protocol for extraction of viral ribonucleic acid (RNA) from water sample concentrates and for quantitatively measuring enterovirus and norovirus concentrations using reverse transcription-quantitative PCR (RT-qPCR). Virus concentrations for the molecular assay are calculated in terms of genomic copies of viral RNA per liter based upon a standard curve. The method uses a number of quality controls to increase data quality and to reduce interlaboratory and intralaboratory variation. The method has been evaluated by examining virus recovery from ground and reagent grade waters seeded with poliovirus type 3 and murine norovirus as a surrogate for human noroviruses. Mean poliovirus recoveries were 20% in groundwaters and 44% in reagent grade water. Mean murine norovirus recoveries with the RT-qPCR assay were 30% in groundwaters and 4% in reagent grade water.

Here we present a procedure to quantify enterovirus and norovirus in environmental and drinking waters using reverse transcription-quantitative PCR. Mean virus recovery from groundwater with this standardized procedure from EPA Method 1615 was 20% for poliovirus and 30% for murine norovirus.

EPA Method 1615 measures enteroviruses and noroviruses present in environmental and drinking waters. This method was developed with the goal of having a ...

Calibrated Passive Sampling - Multi-plot Field Measurements of NH3 Emissions with a Combination of Dynamic Tube Method and Passive Samplers

Agricultural ammonia (NH3) emissions (90% of total EU emissions) are responsible for about 45% airborne eutrophication, 31% soil acidification and 12% fine dust formation within the EU15. But NH3 emissions also mean a considerable loss of nutrients. Many studies on NH3 emission from organic and mineral fertilizer application have been performed in recent decades. Nevertheless, research related to NH3 emissions after application fertilizers is still limited in particular with respect to relationships to emissions, fertilizer type, site conditions and crop growth. Due to the variable response of crops to treatments, effects can only be validated in experimental designs including field replication for statistical testing. The dominating ammonia loss methods yielding quantitative emissions require large field areas, expensive equipment or current supply, which restricts their application in replicated field trials. This protocol describes a new methodology for the measurement of NH3 emissions on many plots linking a simple semi-quantitative measuring method used in all plots, with a quantitative method by simultaneous measurements using both methods on selected plots. As a semi-quantitative measurement method passive samplers are used. The second method is a dynamic chamber method (Dynamic Tube Method) to obtain a transfer quotient, which converts the semi-quantitative losses of the passive sampler to quantitative losses (kg nitrogen ha-1). The principle underlying this approach is that passive samplers placed in a homogeneous experimental field have the same NH3 absorption behavior under identical environmental conditions. Therefore, a transfer co-efficient obtained from single passive samplers can be used to scale the values of all passive samplers used in the same field trial. The method proved valid under a wide range of experimental conditions and is recommended to be used under conditions with bare soil or small canopies (&#60;0.3 m). Results obtained from experiments with taller plants should be treated more carefully.

Calibrated Passive Sampling - Multi-plot Field Measurements of NH3 Emissions with a Combination of Dynamic Tube Method and Passive Samplers

Ammonia emissions are a major threat to the environment by eutrophication, soil acidification and fine particle formation and stem mainly from agricultural sources. This method allows ammonia loss measurements in replicated field trials enabling statistical analysis of emissions and of relationships between crop development and emissions.

Agricultural ammonia (NH3) emissions (90% of total EU emissions) are responsible for about 45% airborne eutrophication, 31% soil acidification and 12% ...

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 ...

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.

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

Continuous Hydrologic and Water Quality Monitoring of Vernal Ponds

Vernal ponds, also referred to as vernal pools, provide critical ecosystem services and habitat for a variety of threatened and endangered species. However, they are vulnerable parts of the landscapes that are often poorly understood and understudied. Land use and management practices, as well as climate change are thought to be a contribution to the global amphibian decline. However, more research is needed to understand the extent of these impacts. Here, we present methodology for characterizing a vernal pond's morphology and detail a monitoring station that can be used to collect water quantity and quality data over the duration of a vernal pond's hydroperiod. We provide methodology for how to conduct field surveys to characterize the morphology and develop stage-storage curves for a vernal pond. Additionally, we provide methodology for monitoring the water level, temperature, pH, oxidation-reduction potential, dissolved oxygen, and electrical conductivity of water in a vernal pond, as well as monitoring rainfall data. This information can be used to better quantify the ecosystem services that vernal ponds provide and the impacts of anthropogenic activities on their ability to provide these services.

Understanding the ecosystem services and processes provided by vernal ponds and the impacts of anthropogenic activities on their ability to provide these services requires intensive hydrologic monitoring. This sampling protocol using in-situ monitoring equipment was developed to understand the impact of anthropogenic activities on water levels and quality.

Vernal ponds, also referred to as vernal pools, provide critical ecosystem services and habitat for a variety of threatened and endangered species. ...

Improving Infrared Spectroscopy Characterization of Soil Organic Matter with Spectral Subtractions

Soil organic matter (SOM) underlies numerous soil processes and functions. Fourier transform infrared (FTIR) spectroscopy detects infrared-active organic bonds that constitute the organic component of soils. However, the relatively low organic matter content of soils (commonly &#60; 5% by mass) and absorbance overlap of mineral and organic functional groups in the mid-infrared (MIR) region (4,000-400 cm-1) engenders substantial interference by dominant mineral absorbances, challenging or even preventing interpretation of spectra for SOM characterization. Spectral subtractions, a post-hoc mathematical treatment of spectra, can reduce mineral interference and enhance resolution of spectral regions corresponding to organic functional groups by mathematically removing mineral absorbances. This requires a mineral-enriched reference spectrum, which can be empirically obtained for a given soil sample by removing SOM. The mineral-enriched reference spectrum is subtracted from the original (untreated) spectrum of the soil sample to produce a spectrum representing SOM absorbances. Common SOM removal methods include high-temperature combustion (&#39;ashing&#39;) and chemical oxidation. Selection of the SOM removal method carries two considerations: (1) the amount of SOM removed, and (2) absorbance artifacts in the mineral reference spectrum and thus the resulting subtraction spectrum. These potential issues can, and should, be identified and quantified in order to avoid fallacious or biased interpretations of spectra for organic functional group composition of SOM. Following SOM removal, the resulting mineral-enriched sample is used to collect a mineral reference spectrum. Several strategies exist to perform subtractions depending on the experimental goals and sample characteristics, most notably the determination of the subtraction factor. The resulting subtraction spectrum requires careful interpretation based on the aforementioned methodology. For many soil and other environmental samples containing substantial mineral components, subtractions have strong potential to improve FTIR spectroscopic characterization of organic matter composition.

SOM underlies many soil functions and processes, but its characterization by FTIR spectroscopy is often challenged by mineral interferences. The described method can increase the utility of SOM analysis by FTIR spectroscopy by subtracting mineral interferences in soil spectra using empirically obtained mineral reference spectra.

Soil organic matter (SOM) underlies numerous soil processes and functions. Fourier transform infrared (FTIR) spectroscopy detects infrared-active organic ...

The Plant Infection Test: Spray and Wound-Mediated Inoculation with the Plant Pathogen Magnaporthe Grisea

Plants possess a powerful system to defend themselves against potential threats by pathogenic fungi. For agriculturally important plants, however, current measures to combat such pathogens have proved too conservative and, thus, not sufficiently effective, and they can potentially pose environmental risks. Therefore, it is extremely necessary to identify host-resistance factors to assist in controlling plant diseases naturally through the identification of resistant germplasm, the isolation and characterization of resistance genes, and the molecular breeding of resistant cultivars. In this regard, there is need to establish an accurate, rapid, and large-scale inoculation method to breed and develop plant resistance genes. The rice blast fungal pathogen Magnaporthe grisea causes severe disease symptoms and yield losses. Recently, M. grisea has emerged as a model organism for studying the mechanisms of plant-fungal pathogen interactions. Hence, we report the development of a plant virulence test method that is specific for M. grisea. This method provides for both spray inoculation with a conidial suspension and wounding inoculation with mycelium cubes or droplets of conidial suspension. The key step of the wounding inoculation method for detached rice leaves is to make wounds on plant leaves, which avoids any interference caused by host penetration resistance. This spray/wounding protocol contributes to the rapid, accurate, and large-scale screening of the pathotypes of M. grisea isolates. This integrated and systematic plant infection method will serve as an excellent starting point for gaining a broad perspective of issues in plant pathology.

The Plant Infection Test: Spray and Wound-Mediated Inoculation with the Plant Pathogen Magnaporthe Grisea

Here, we present a protocol to test plant virulence with the plant pathogen Magnaporthe grisea. This report will contribute to the large-scale screening of the pathotypes of fungi isolates and serve as an excellent starting point for understanding the resistant mechanisms of plants during molecular breeding.

Plants possess a powerful system to defend themselves against potential threats by pathogenic fungi. For agriculturally important plants, however, current ...

Visualizing Efficacy of Pesticides Against Disease Vector Mosquitoes in the Field

Efficacy of public health pesticides targeting nuisance and disease-vector insects such as mosquitoes, sand flies, and filth-breeding flies is not uniform across ecological zones. To best protect public and veterinary health from these insects, the environmental limitations of pesticides need to be investigated to inform effective use of the most appropriate pesticide formulations and techniques. We have developed a research program to evaluate combinations of pesticides, pesticide application equipment, and application techniques in hot-arid desert, hot-humid tropical, warm and cool temperate, and urban locations to derive pesticide use guidelines specific to target insect and environment. To these ends we designed a system of protocols to support efficient, cost-effective, portable, and standardized evaluation of a diverse range of pesticides and equipment across multiple environments. At the core of these protocols is the use of an array of small cages with colony-reared sentinel mosquitoes (adults and immatures) and sand flies (adults), strategically arranged in natural habitats and exposed to pesticide spray. Spatial and temporal patterns of pesticide efficacy are derived from percent mortality in sentinel cages, then mapped and visualized in a geographic information system. Maps of sentinel mortality data may be statistically compared to evaluate relative efficacy of a pesticide across multiple environments, or to study multiple pesticides in a single environment. Protocols may be modified to accommodate a variety of scenarios, including, for example, the vertical orientation of sentinels in canopy habitats or simultaneous testing of ground and aerial application methods.

The efficacy of public health pesticides targeting nuisance and disease-vector insects is not uniform across different ecological zones. Here we present a system of techniques using captive vector insects as sentinels for pesticide efficacy to derive electronic maps supporting the standard evaluation of pesticides across multiple environments.

Efficacy of public health pesticides targeting nuisance and disease-vector insects such as mosquitoes, sand flies, and filth-breeding flies is not uniform ...