Chemcatcher

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Chemcatcher is a passive sampling device for monitoring a variety of pollutants (including trace metals, polycyclic aromatic hydrocarbons, pesticides and pharmaceutical residues) in water. [1] It is a reusable three component, water-tight PTFE body. Two different designs are available to accommodate different types of commercially available 47 mm diameter receiving phase disks.

Contents

Background

Most monitoring programmes involve the periodic collection of low volume spot samples (bottle or grab) of water, which is challenging, particularly where levels fluctuate over time and when chemicals are only present at trace, yet toxicologically relevant concentrations. Chemcatcher is used to measure time-weighted average (TWA) or equilibrium concentrations of a wide range of pollutants in water. This allows the end user to obtain a more representative picture of the chemicals that may be present in the aquatic environment.

Development

The Chemcatcher concept was developed [2] [3] by Professors Richard Greenwood and Graham Mills at the University of Portsmouth, together with colleagues from Chalmers University of Technology, Sweden. The device is patented [4] [5] in a number of countries and the name is a registered trademark in Ireland and the United Kingdom. [6]

T.E. Laboratories (TelLab), based in Tullow, Ireland, holds the global licence to manufacture and sell Chemcatcher.

Use

The sampler can be deployed in the field for extended periods of time ranging from days to weeks. The specific pollutants of interest are sequestered by the samplers and these are retained on the receiving phase disk. After retrieval from the environment the pollutants are eluted from the disk and analysed in the laboratory using conventional instrumental methods. In order to obtain TWA concentrations the sampler must first be calibrated in the laboratory so as to ascertain the uptake rate (usually measured as the volume of water cleared per unit time i.e. L/h for the analyte) of the pollutant of interest. Chemcatcher has been used in a range of aquatic environments; however, most work to date has been in monitoring the TWA concentrations of priority and emerging pollutants in surface waters. [7] [8] [9]

The use of passive sampling devices, [10] [11] such as Chemcatcher or polar organic chemical integrative sampler (POCIS), has a number of advantages over the use of spot or bottle sampling for monitoring pollutants in the aquatic environment. The latter technique gives only an instantaneous concentration of the pollutant as the specific time of sampling. Passive samplers, depending on their mode of use, can give either the TWA or equilibrium concentration of the pollutant over the deployment period. The measurement of TWA concentrations can give a better indication of the long-term environmental conditions and enables improved risk assessment. Chemcatcher can be used to monitor both polar and non-polar compounds.

Related Research Articles

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<span class="mw-page-title-main">Water pollution</span> Contamination of water bodies

Water pollution is the contamination of water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. Water pollution results when contaminants mix with these water bodies. Contaminants can come from one of four main sources. These are sewage discharges, industrial activities, agricultural activities, and urban runoff including stormwater. Water pollution may affect either surface water or groundwater. This form of pollution can lead to many problems. One is the degradation of aquatic ecosystems. Another is spreading water-borne diseases when people use polluted water for drinking or irrigation. Water pollution also reduces the ecosystem services such as drinking water provided by the water resource.

<span class="mw-page-title-main">Biochemical oxygen demand</span> Oxygen needed to remove organics from water

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<span class="mw-page-title-main">Aquatic toxicology</span> Study of manufactured products on aquatic organisms

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<span class="mw-page-title-main">Bromoform</span> Chemical compound

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<span class="mw-page-title-main">Bioindicator</span> Species that reveals the status of an environment

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<span class="mw-page-title-main">Environmental monitoring</span> Monitoring of the quality of the environment

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A polar organic chemical integrative sampler (POCIS) is a passive sampling device which allows for the in situ collection of a time-integrated average of hydrophilic organic contaminants developed by researchers with the United States Geological Survey in Columbia, Missouri. POCIS provides a means for estimating the toxicological significance of waterborne contaminants. The POCIS sampler mimics the respiratory exposure of organisms living in the aquatic environment and can provide an understanding of bioavailable contaminants present in the system. POCIS can be deployed in a wide range of aquatic environments and is commonly used to assist in environmental monitoring studies.

<span class="mw-page-title-main">Diffusive gradients in thin films</span> Environmental chemistry technique

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<span class="mw-page-title-main">Air pollution measurement</span>

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<span class="mw-page-title-main">Stabilized liquid membrane devices</span>

A stabilized liquid membrane device or SLMD is a type of passive sampling device which allows for the in situ, integrative collection of waterborne, labile ionic metal contaminants. By capturing and sequestering metal ions onto its surface continuously over a period of days to weeks, an SLMD can provide an integrative measurement of bioavailable toxic metal ions present in the aqueous environment. As such, they have been used in conjunction with other passive samplers in ecological field studies.

<span class="mw-page-title-main">Passive sampling</span>

Passive sampling is an environmental monitoring technique involving the use of a collecting medium, such as a man-made device or biological organism, to accumulate chemical pollutants in the environment over time. This is in contrast to grab sampling, which involves taking a sample directly from the media of interest at one point in time. In passive sampling, average chemical concentrations are calculated over a device's deployment time, which avoids the need to visit a sampling site multiple times to collect multiple representative samples. Currently, passive samplers have been developed and deployed to detect toxic metals, pesticides, pharmaceuticals, radionuclides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and other organic compounds in water, while some passive samplers can detect hazardous substances in the air.

A diffusion tube is a scientific device that passively samples the concentration of one or more gases in the air, commonly used to monitor average air pollution levels over a period ranging from days to about a month. Diffusion tubes are widely used by local authorities for monitoring air quality in urban areas, in citizen science pollution-monitoring projects carried out by community groups and schools, and in indoor environments such as mines and museums.

References

  1. Adeline Charriau; Sophie Lissalde; Gaëlle Poulier; Nicolas Mazzella; Rémy Buzier; Gilles Guibaud (2016). "Overview of the Chemcatcher® for the passive sampling of various pollutants in aquatic environments Part A: Principles, calibration, preparation and analysis of the sampler". Talanta. 148: 556–571. doi:10.1016/j.talanta.2015.06.064. ISSN   0039-9140.
  2. Kingston J, Greenwood R, Mills GA, Morrison GM, Björklund-Persson L (2000). "Development of a novel passive sampling system for the timed-averaged measurement of a range of organic pollutants in aquatic environments". J Environ Monit. 2 (5): 487–495. doi:10.1039/b003532g. PMID   11254055.
  3. Björklund L, Morrison GM, Friemann JU, Kingston J, Mills GA, Greenwood R (2001). "Diffusional behaviour of metals in a passive sampling system for monitoring aquatic pollution". J Environ Monit. 3 (6): 639–645. doi:10.1039/b107959j. PMID   11785639.
  4. Greenwood, R; Kingston J; Mills GA; Morrison G; Björklund-Persson L. "Design and application of passive sampling device for the timed-average measurement of organic compounds in the aquatic environment". UK Patent No 2353860: Granted February 2004.
  5. Greenwood, R; Kingston J; Mills GA; Morrison G; Björklund-Persson L. "Design and application of passive sampling device for the timed-average measurement of organic compounds in the aquatic environment". US Patent Application No. 10/069351: Granted June 2006.
  6. Intellectual Property Office. "Case details for Trade Mark 2450451" . Retrieved 21 September 2011.
  7. Allan, IJ; Knutsson J; Guigues N; Mills GA; Fouillac A-M; Greenwood R (2008). "Chemcatcher and DGT passive sampling devices for regulatory monitoring of trace metals in surface water". J Environ Monit. 10 (7): 821–829. doi:10.1039/b802581a. PMID   18688449.
  8. Vrana, B; Mills GA; Leonards PEG; Kotterman M; Weideborg M; Hajslova J; Kocourek V; Tomaniova M; Pulkrabova J; Suchanova M; Hajkova K; Herve S; Ahkola H; Greenwood R (2010). "Field performance of the Chemcatcher passive sampler for monitoring hydrophobic organic pollutants in surface water". J Environ Monit. 12 (4): 863–872. doi:10.1039/b923073d. PMID   20383367.
  9. Allan, IJ; Booij K; Paschke A; Vrana B; Mills GA; Greenwood R (2009). "Field performance of seven passive sampling devices for monitoring of hydrophobic substances". Environ Sci Technol. 43 (14): 5383–5390. doi:10.1021/es900608w. PMID   19708370.
  10. Greenwood, R; Mills, G; Vrana, B, eds. (2007). Passive sampling techniques in environmental monitoring (Comprehensive Analytical Chemistry series, D Barcelo (series ed.). Amsterdam: Elsevier. pp.  453. ISBN   978-0-444-52225-2. Archived from the original on 2012-10-14. Retrieved 2011-09-21.{{cite book}}: CS1 maint: bot: original URL status unknown (link) Archived 2012-10-14 at the Wayback Machine
  11. Vrana, B; et al. (2005). "Passive sampling techniques for monitoring of pollutants in water (Review Article)". TrAC Trends in Analytical Chemistry. 24 (10): 845–868. doi:10.1016/j.trac.2005.06.006.