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Advances made on many different fronts
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
Andrea Jaquins Gerstl, I. Mitch Taylor, Zhan Shu, Hong Zhang, Stephen G. Weber
Source:TrAC Trends in Analytical Chemistry, Volume 36
Andrea Jaquins Gerstl, I. Mitch Taylor, Zhan Shu, Hong Zhang, Stephen G. Weber
Chemical monitoring activity for the implementation of the Water Framework Directive
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
Philippe Quevauviller, Mario Carere, Stefano Polesello
Source:TrAC Trends in Analytical Chemistry, Volume 36
Philippe Quevauviller, Mario Carere, Stefano Polesello
Chemical monitoring and emerging pollutants in the Common Implementation Strategy of the Water Framework Directive
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
Mario Carere, Stefano Polesello, Caterina Sollazzo, Bernd Manfred Gawlik
This Foreword gives an overview on the last two mandates on Chemical Monitoring under the Common Implementation Strategy of the Water Framework Directive. It describes the development from 2005 until today, highlighting the various topics being addressed by the expert group. It sets the work into the relationship of the policy-making process as regards chemical-monitoring aspects for priority substances and emerging contaminants.
Source:TrAC Trends in Analytical Chemistry, Volume 36
Mario Carere, Stefano Polesello, Caterina Sollazzo, Bernd Manfred Gawlik
This Foreword gives an overview on the last two mandates on Chemical Monitoring under the Common Implementation Strategy of the Water Framework Directive. It describes the development from 2005 until today, highlighting the various topics being addressed by the expert group. It sets the work into the relationship of the policy-making process as regards chemical-monitoring aspects for priority substances and emerging contaminants.
Guidance for sediment and biota monitoring under the Common Implementation Strategy for the Water Framework Directive
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
Mario Carere, Valeria Dulio, Georg Hanke, Stefano Polesello
The Environmental Quality Standards Directive 2008/105/EC (EQSD) marks an important step in the use of sediments and biota as matrices for chemical-status assessment under the Water Framework Directive 2000/60/EC (WFD). Analysis of contaminants in sediments and biota is indeed widely recognized as a cost-effective approach in water-quality monitoring to describe the general contamination level, to supply reference values for local and regional monitoring and to identify areas of concern where additional monitoring effort is needed. Because of the explicit reference in the EQSD to the use of sediments and biota as preferred matrices for the monitoring of substances with accumulation potential – especially for the assessment of long-term trends, but also for compliance checking, wherever appropriate – Member States of the European Union (EU) asked the European Commission to publish a guidance document to enhance the degree of harmonization among EU countries in chemical monitoring of sediments and biota, taking into account best available techniques, standard procedures and common practices. This article presents the key features of that guidance document, its main recommendations for chemical monitoring of sediments and biota and the scope for further improvement in current monitoring practices.
Source:TrAC Trends in Analytical Chemistry, Volume 36
Mario Carere, Valeria Dulio, Georg Hanke, Stefano Polesello
The Environmental Quality Standards Directive 2008/105/EC (EQSD) marks an important step in the use of sediments and biota as matrices for chemical-status assessment under the Water Framework Directive 2000/60/EC (WFD). Analysis of contaminants in sediments and biota is indeed widely recognized as a cost-effective approach in water-quality monitoring to describe the general contamination level, to supply reference values for local and regional monitoring and to identify areas of concern where additional monitoring effort is needed. Because of the explicit reference in the EQSD to the use of sediments and biota as preferred matrices for the monitoring of substances with accumulation potential – especially for the assessment of long-term trends, but also for compliance checking, wherever appropriate – Member States of the European Union (EU) asked the European Commission to publish a guidance document to enhance the degree of harmonization among EU countries in chemical monitoring of sediments and biota, taking into account best available techniques, standard procedures and common practices. This article presents the key features of that guidance document, its main recommendations for chemical monitoring of sediments and biota and the scope for further improvement in current monitoring practices.
Highlights
► The European Commission developed Guidance on monitoring of sediment and biota. ► The Guidance addresses harmonization on monitoring sediment and biota in EU countries. ► Practically applying Water Framework and Environmental Quality Standards Directives.Chemical-monitoring on-site exercises to harmonize analytical methods for priority substances in the European Union
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
Georg Hanke, Giulio Mariani, Sara Comero, Robert Loos, Giovanni Bidoglio, Stefano Polesello, Sara Valsecchi, Marianna Rusconi, Jan Wollgast, Javier Castro-Jiménez, Luisa Patrolecco, Nicoletta Ademollo
In support of the implementation of the Water Framework Directive (WFD, 2000/60/EC), three intercomparison exercises were carried out on European rivers (Po, Danube and Meuse) in order to assess the current state of monitoring methodologies. Laboratories from European Union (EU) Member States (MSs) were invited to gather at the selected EU river and sample together, each laboratory with its own method. Participants simultaneously sampled the river water and analyzed according to their protocols. A selection of priority substances (PSs) [i.e. polybromodiphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs) and alkyl phenols (APs)] included in Directive 2008/105/EC were analyzed in standard solutions, extracts from river waters and river-water samples in order to investigate variabilities in different steps of the analytical process. Concentrations measured in river samples using WFD-monitoring protocols showed that even some of the most challenging WFD PSs (e.g., PAHs, PBDEs and APs) can be measured at WFD-relevant concentrations with methods currently applied in MSs, but variability is still too great and not all laboratories meet required limits of quantification. Hindrance to the implementation of the monitoring requirements is therefore not the technical feasibility of analysis at these concentration levels, but rather communication, knowledge exchange and harmonization among the laboratories involved.
Source:TrAC Trends in Analytical Chemistry, Volume 36
Georg Hanke, Giulio Mariani, Sara Comero, Robert Loos, Giovanni Bidoglio, Stefano Polesello, Sara Valsecchi, Marianna Rusconi, Jan Wollgast, Javier Castro-Jiménez, Luisa Patrolecco, Nicoletta Ademollo
In support of the implementation of the Water Framework Directive (WFD, 2000/60/EC), three intercomparison exercises were carried out on European rivers (Po, Danube and Meuse) in order to assess the current state of monitoring methodologies. Laboratories from European Union (EU) Member States (MSs) were invited to gather at the selected EU river and sample together, each laboratory with its own method. Participants simultaneously sampled the river water and analyzed according to their protocols. A selection of priority substances (PSs) [i.e. polybromodiphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs) and alkyl phenols (APs)] included in Directive 2008/105/EC were analyzed in standard solutions, extracts from river waters and river-water samples in order to investigate variabilities in different steps of the analytical process. Concentrations measured in river samples using WFD-monitoring protocols showed that even some of the most challenging WFD PSs (e.g., PAHs, PBDEs and APs) can be measured at WFD-relevant concentrations with methods currently applied in MSs, but variability is still too great and not all laboratories meet required limits of quantification. Hindrance to the implementation of the monitoring requirements is therefore not the technical feasibility of analysis at these concentration levels, but rather communication, knowledge exchange and harmonization among the laboratories involved.
Highlights
► European intercomparison for implementation of the Water Framework Directive. ► Current state of monitoring methods for PAHs, PDBEs and alkyl phenols in EU rivers. ► Harmonization of monitoring procedures among laboratories is needed.Testing sample stability in short-term isochronous stability studies for EU-wide monitoring surveys of polar organic contaminants in water
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
Bernd Manfred Gawlik, Robert Loos, Giovanni Bidoglio, Gisela Fauler, Xinghua Guo, Ernst Lankmayr, Thomas Linsinger
The article introduces the European Union (EU)-wide monitoring concept as run by the European Commission’s Joint Research Centre (JRC) and specifically addresses the issue of stability tests for environmental specimen and samples using the so-called isochronous stability-test design. We briefly describe the underlying statistical concept and apply it to water samples being collected in the context of the JRC’s EU-wide environmental monitoring activities. The stability of spiked tap-water and river-water samples and their containers was assessed at 4°C, 20°C and 40°C using ibuprofen, gemfibrozil, ketoprofen, diclofenac, bezafibrate, naproxen, perfluoroheptanoate (PFHpA), perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), carbamzepine, sulfamethoxazole, terbutylazine and triclosan as test substances in two different stability-testing schemes. The stability of the samples decreased as expected with an increase in the storage temperature. Uncertainty contributions were calculated and it was concluded that this type of sample remains stable for ca. 6weeks if stored at 4°C.
Source:TrAC Trends in Analytical Chemistry, Volume 36
Bernd Manfred Gawlik, Robert Loos, Giovanni Bidoglio, Gisela Fauler, Xinghua Guo, Ernst Lankmayr, Thomas Linsinger
The article introduces the European Union (EU)-wide monitoring concept as run by the European Commission’s Joint Research Centre (JRC) and specifically addresses the issue of stability tests for environmental specimen and samples using the so-called isochronous stability-test design. We briefly describe the underlying statistical concept and apply it to water samples being collected in the context of the JRC’s EU-wide environmental monitoring activities. The stability of spiked tap-water and river-water samples and their containers was assessed at 4°C, 20°C and 40°C using ibuprofen, gemfibrozil, ketoprofen, diclofenac, bezafibrate, naproxen, perfluoroheptanoate (PFHpA), perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), carbamzepine, sulfamethoxazole, terbutylazine and triclosan as test substances in two different stability-testing schemes. The stability of the samples decreased as expected with an increase in the storage temperature. Uncertainty contributions were calculated and it was concluded that this type of sample remains stable for ca. 6weeks if stored at 4°C.
Highlights
► We developed a non-probabilistic, pan-European snapshot mechanism for water samples. ► It is used to derive benchmarks and links to regional chemical-monitoring programs. ► We addressed the issue of analyte stability in water samples. ► We applied the isochronous stability test used for reference materials. ► We used data directly to feed into policy implementation.Chemical water monitoring under the Water Framework Directive with Certified Reference Materials
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
Marina Ricci, Ivan Kourtchev, Hendrik Emons
In the field of environment protection, a series of European Directives with special emphasis on the water bodies has been approved as a cascade after the milestone Water Framework Directive (WFD) of the year 2000. The most recent piece of legislation, Directive 2009/90/EC, points out the necessity of ensuring the quality of the analytical data and prescribes that the laboratories appointed by the Member States as responsible for the chemical water monitoring shall “demonstrate their competences…by…analysis of available reference materials…”. Certified Reference Materials (CRMs) are the anchor points for comparability of measurement results, in both space and time, ensuring their traceability to a common reference. In this article, we present a critical overview of existing matrix CRMs, related to WFD monitoring needs. Our survey concerns available water, biota and sediment matrix CRMs for the 33 Priority Substances (PSs) (and the eight “other certain pollutants”) listed in the WFD, together with a reference to discontinued CRMs. Tables providing a more synoptic view are available on-line as supplementary information. For the four priority metals (Cd, Pb, Hg and Ni), there are sufficient CRMs for all matrices considered to cover the needs of the monitoring laboratories, but there is a serious lack of matrix CRMs for most of the organic PSs. Also, for the matrix water, there are no materials available for organic pollutants that could be classified as CRMs as commonly understood. We also briefly discuss pure compounds and solution CRMs for calibration purposes. In the final section, we show how a CRM could be used in the estimation of measurement uncertainty for checking compliance at the Environmental Quality Standard level, according to the technical specifications given in Directive 2009/90/EC.
Source:TrAC Trends in Analytical Chemistry, Volume 36
Marina Ricci, Ivan Kourtchev, Hendrik Emons
In the field of environment protection, a series of European Directives with special emphasis on the water bodies has been approved as a cascade after the milestone Water Framework Directive (WFD) of the year 2000. The most recent piece of legislation, Directive 2009/90/EC, points out the necessity of ensuring the quality of the analytical data and prescribes that the laboratories appointed by the Member States as responsible for the chemical water monitoring shall “demonstrate their competences…by…analysis of available reference materials…”. Certified Reference Materials (CRMs) are the anchor points for comparability of measurement results, in both space and time, ensuring their traceability to a common reference. In this article, we present a critical overview of existing matrix CRMs, related to WFD monitoring needs. Our survey concerns available water, biota and sediment matrix CRMs for the 33 Priority Substances (PSs) (and the eight “other certain pollutants”) listed in the WFD, together with a reference to discontinued CRMs. Tables providing a more synoptic view are available on-line as supplementary information. For the four priority metals (Cd, Pb, Hg and Ni), there are sufficient CRMs for all matrices considered to cover the needs of the monitoring laboratories, but there is a serious lack of matrix CRMs for most of the organic PSs. Also, for the matrix water, there are no materials available for organic pollutants that could be classified as CRMs as commonly understood. We also briefly discuss pure compounds and solution CRMs for calibration purposes. In the final section, we show how a CRM could be used in the estimation of measurement uncertainty for checking compliance at the Environmental Quality Standard level, according to the technical specifications given in Directive 2009/90/EC.
Highlights
► Quality and comparability of water chemical monitoring results should be ensured. ► CRMs are necessary for quality assurance and quality control of measurement results. ► Water, biota and sediment matrix CRMs for Cd, Pb, Hg and Ni are generally available. ► There are no water-matrix CRMs for organic priority substances under the WFD. ► Biota and sediment CRMs exist only for some organic priority substances under the WFD.Monitoring of contaminants in suspended particulate matter as an alternative to sediments
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
Birgit Schubert, Peter Heininger, Martin Keller, Evelyn Claus, Mathias Ricking
The Water Framework Directive (WFD) requires Member States of the European Union to achieve good status of all waters in 2015. The survey of chemical status focuses on checking compliance of the quality of water systems against environmental quality standards and temporal trend monitoring of contaminants in sediments and/or biota. As sediments appropriate for monitoring contaminants may not always be available, we discuss the use of suspended particulate matter (SPM) as an alternative. We describe and discuss differences in quality and quantity of sediments and SPM collected by different sampling techniques with regard to the respective advantages and drawbacks for various monitoring purposes. Often, both contaminant concentrations in sediments and in SPM may give the required information. However, selection of the technique applied for collecting SPM should take into consideration, inter alia, the purpose of the monitoring, as well as the hydrodynamic and morphological conditions of the area monitored. We illustrate general conclusions with field applications from the European rivers Rhine and Elbe.
Source:TrAC Trends in Analytical Chemistry, Volume 36
Birgit Schubert, Peter Heininger, Martin Keller, Evelyn Claus, Mathias Ricking
The Water Framework Directive (WFD) requires Member States of the European Union to achieve good status of all waters in 2015. The survey of chemical status focuses on checking compliance of the quality of water systems against environmental quality standards and temporal trend monitoring of contaminants in sediments and/or biota. As sediments appropriate for monitoring contaminants may not always be available, we discuss the use of suspended particulate matter (SPM) as an alternative. We describe and discuss differences in quality and quantity of sediments and SPM collected by different sampling techniques with regard to the respective advantages and drawbacks for various monitoring purposes. Often, both contaminant concentrations in sediments and in SPM may give the required information. However, selection of the technique applied for collecting SPM should take into consideration, inter alia, the purpose of the monitoring, as well as the hydrodynamic and morphological conditions of the area monitored. We illustrate general conclusions with field applications from the European rivers Rhine and Elbe.
Highlights
► Suspended particulate matter (SPM) and sediments accumulate hydrophobic contaminants. ► The WFD requires trend monitoring of contaminants in sediments and/or biota. ► We compare the use of SPM and sediments for contaminant monitoring. ► Contaminant monitoring may be carried out for various purposes. ► The techniques described are applicable to rivers, estuaries and coastal systems.The analytical problem of measuring total concentrations of organic pollutants in whole water
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
N. Ademollo, L. Patrolecco, S. Polesello, S. Valsecchi, J. Wollgast, G. Mariani, G. Hanke
The Water Framework Directive (WFD) (2000/60/EC) of the European Union provides protection from chemical pollutants through the Environmental Quality Standards (EQS) Directive (2008/105/EC), which sets EQSs for priority substances (PSs) and certain other pollutants, according to the requirements set out in Article 16(8) of the WFD. For organic PSs, these EQSs are expressed as total concentrations in the whole-water sample. Total concentrations can be obtained by direct analysis of the whole-water sample or by separate determinations on filterable and solid phases. Both solutions have their advantages and drawbacks, which we critically discuss in the present review. Analysis of data in the literature and experience from standardization activities show that it is possible to find a simple extraction method for analyzing whole water without time-consuming separation steps. The solid-phase extraction disk is now subject to standardization efforts as the most promising technique to achieve this goal. We discuss limitations of this approach in the light of the consequences for chemical-status assessment.
Source:TrAC Trends in Analytical Chemistry, Volume 36
N. Ademollo, L. Patrolecco, S. Polesello, S. Valsecchi, J. Wollgast, G. Mariani, G. Hanke
The Water Framework Directive (WFD) (2000/60/EC) of the European Union provides protection from chemical pollutants through the Environmental Quality Standards (EQS) Directive (2008/105/EC), which sets EQSs for priority substances (PSs) and certain other pollutants, according to the requirements set out in Article 16(8) of the WFD. For organic PSs, these EQSs are expressed as total concentrations in the whole-water sample. Total concentrations can be obtained by direct analysis of the whole-water sample or by separate determinations on filterable and solid phases. Both solutions have their advantages and drawbacks, which we critically discuss in the present review. Analysis of data in the literature and experience from standardization activities show that it is possible to find a simple extraction method for analyzing whole water without time-consuming separation steps. The solid-phase extraction disk is now subject to standardization efforts as the most promising technique to achieve this goal. We discuss limitations of this approach in the light of the consequences for chemical-status assessment.
Highlights
► Whole-water analysis is carried out by direct analysis or separate determinations. ► We discuss the ways to analyze organics in whole water without separation. ► It is possible to use membrane-disk extraction for whole-water analysis. ► For whole-water analysis, membrane disks are validated in standardization activities. ► Limitations in whole-water analysis in the light of chemical-status assessment.Sediment and biota in trend monitoring of contaminants in transitional waters
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
C. Maggi, A. Ausili, R. Boscolo, F. Cacciatore, A. Bonometto, M. Cornello, D. Berto
According to Directive 2008/105/EC, the Italian Parliament issued in 2010 the Legislative Decree 219, which determined the environmental quality standard (EQS) for sediment of marine coastal areas, lagoons and coastal ponds. For the purpose of trend monitoring, sediment and biota are the most suitable matrices for many substances. Directive 2008/105/EC gives an indication of the substances that should be taken into consideration for trend monitoring and sets an integrated water-management plan, which has to be prepared for each river-basin district. This article illustrates the criteria that were applied to draw the plan with the aim of assessing the trends of several substances in sediment and biota of the Lagoon of Venice, taking into account the recommendations of Directive 2000/60/EC and the daughter Directives. For this purpose, contaminant concentrations coming from a survey conducted in 2005 were compared with the Italian EQS. Results allowed for the evaluation of spatial and temporal trends of several contaminants in sediments and mollusks of the Lagoon of Venice. They allowed us to focus on which compounds need further monitoring and, most of all, which pollutants require measures to reduce inputs.
Source:TrAC Trends in Analytical Chemistry, Volume 36
C. Maggi, A. Ausili, R. Boscolo, F. Cacciatore, A. Bonometto, M. Cornello, D. Berto
According to Directive 2008/105/EC, the Italian Parliament issued in 2010 the Legislative Decree 219, which determined the environmental quality standard (EQS) for sediment of marine coastal areas, lagoons and coastal ponds. For the purpose of trend monitoring, sediment and biota are the most suitable matrices for many substances. Directive 2008/105/EC gives an indication of the substances that should be taken into consideration for trend monitoring and sets an integrated water-management plan, which has to be prepared for each river-basin district. This article illustrates the criteria that were applied to draw the plan with the aim of assessing the trends of several substances in sediment and biota of the Lagoon of Venice, taking into account the recommendations of Directive 2000/60/EC and the daughter Directives. For this purpose, contaminant concentrations coming from a survey conducted in 2005 were compared with the Italian EQS. Results allowed for the evaluation of spatial and temporal trends of several contaminants in sediments and mollusks of the Lagoon of Venice. They allowed us to focus on which compounds need further monitoring and, most of all, which pollutants require measures to reduce inputs.
Highlights
► We assessed the trend monitoring of contaminants in the Lagoon of Venice. ► For the purpose of trend monitoring, we investigated sediment and biota. ► Directive 2008/105/EC states Member States must set Integrated Water Management Plans. ► Results used for the Sediment Monitoring Plan (2010–2012) for the Lagoon of Venice.Biomonitoring of lake sediments using benthic macroinvertebrates
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
R. Bettinetti, B. Ponti, L. Marziali, B. Rossaro
The Water Framework Directive (2000/60/EC) is an innovative piece of legislation aimed at protecting the quality of all continental and coastal waters in Europe through an ecological evaluation of the ecosystems. Since it is widely acknowledged that the greater the ecological realism the greater the difficulty of its definition, we describe the different uses of benthic organisms as a tool for assessing the quality of sediment in lakes. We review the responses from single species to the community. We focus on studies in the laboratory and in the field, and we also critically consider the use of predictive models for these evaluations. Our discussion of the information collected underlines the importance of the relation between sensitivity of single species and contaminants. Moreover, the recent approach in developing mechanistic models to predict the response of natural communities seems to be particularly powerful for community ecology, and we strongly recommend more effort along these lines.
Source:TrAC Trends in Analytical Chemistry, Volume 36
R. Bettinetti, B. Ponti, L. Marziali, B. Rossaro
The Water Framework Directive (2000/60/EC) is an innovative piece of legislation aimed at protecting the quality of all continental and coastal waters in Europe through an ecological evaluation of the ecosystems. Since it is widely acknowledged that the greater the ecological realism the greater the difficulty of its definition, we describe the different uses of benthic organisms as a tool for assessing the quality of sediment in lakes. We review the responses from single species to the community. We focus on studies in the laboratory and in the field, and we also critically consider the use of predictive models for these evaluations. Our discussion of the information collected underlines the importance of the relation between sensitivity of single species and contaminants. Moreover, the recent approach in developing mechanistic models to predict the response of natural communities seems to be particularly powerful for community ecology, and we strongly recommend more effort along these lines.
Highlights
► Macroinvertebrates are used as indicators of lake sediment toxicity in laboratory and field tests. ► Biomarkers provide early warning of contamination of lake sediments in the field. ► Mesocosms can assist study of the response of a community to toxic contamination. ► Biotic indices and species traits can measure community structure and functioning as response to toxic contamination.Importance of dietary uptake of trace elements in the benthic deposit-feeding Lumbriculus variegatus
31 May 2012,
09:59:40
Publication year: 2012
Source:TrAC Trends in Analytical Chemistry, Volume 36
Marina Camusso, Stefano Polesello, Sara Valsecchi, Davide A.L. Vignati
The Water Framework Directive and daughter Directives of the European Union state that a risk-assessment approach should be used to set Environmental Quality Standards (EQSs) for different environmental compartments, including sediments. The derivation of sediment QSs is particularly relevant for substances that accumulate in sediment and could pose a risk through direct toxicity to benthic invertebrates, or to benthic predators through the food chain (secondary poisoning). For metals, total concentrations in sediment are not usually directly related to ecotoxicological effects because of variable natural background levels, and many abiotic and biotic factors can modify their bioaccessibility and bioavailability. The most common methods for incorporating bioavailability correction in QSsediment refer to the medium in which organisms live and determine only the chemical availability (bioaccessibility sensu) of elements, assuming that the available fraction is independent of the organisms to protect. However, there is significant evidence that the bioavailable fraction also depends on the feeding behavior and the ecology of biota, especially when the diet (sediment intake) is the main route of uptake. In the present work, we apply the Biodynamic Model to literature and original unpublished data of trace-element bioaccumulation in the sediment-dwelling oligochaete Lumbriculus variegatus to assess the main factors that affect the bioaccumulation and hence the bioavailable fraction in sediments. Results highlighted that, for L. variegatus, there is not a single, predominant route of uptake for all the elements considered. Ni is accumulated mainly from pore water. Sediment ingestion is the main uptake route for As, Cd, Cu and Zn. Pb body burden seems to depend on both the freely dissolved concentration in pore water and the dietary uptake. When diet is the main route of uptake, trace-element bioaccumulation is strongly controlled by the sediment-ingestion rate, which is itself a function of organic carbon (OC) content. We discuss the implications of these findings for the derivation of QSsediment and explore avenues for future research.
Source:TrAC Trends in Analytical Chemistry, Volume 36
Marina Camusso, Stefano Polesello, Sara Valsecchi, Davide A.L. Vignati
The Water Framework Directive and daughter Directives of the European Union state that a risk-assessment approach should be used to set Environmental Quality Standards (EQSs) for different environmental compartments, including sediments. The derivation of sediment QSs is particularly relevant for substances that accumulate in sediment and could pose a risk through direct toxicity to benthic invertebrates, or to benthic predators through the food chain (secondary poisoning). For metals, total concentrations in sediment are not usually directly related to ecotoxicological effects because of variable natural background levels, and many abiotic and biotic factors can modify their bioaccessibility and bioavailability. The most common methods for incorporating bioavailability correction in QSsediment refer to the medium in which organisms live and determine only the chemical availability (bioaccessibility sensu) of elements, assuming that the available fraction is independent of the organisms to protect. However, there is significant evidence that the bioavailable fraction also depends on the feeding behavior and the ecology of biota, especially when the diet (sediment intake) is the main route of uptake. In the present work, we apply the Biodynamic Model to literature and original unpublished data of trace-element bioaccumulation in the sediment-dwelling oligochaete Lumbriculus variegatus to assess the main factors that affect the bioaccumulation and hence the bioavailable fraction in sediments. Results highlighted that, for L. variegatus, there is not a single, predominant route of uptake for all the elements considered. Ni is accumulated mainly from pore water. Sediment ingestion is the main uptake route for As, Cd, Cu and Zn. Pb body burden seems to depend on both the freely dissolved concentration in pore water and the dietary uptake. When diet is the main route of uptake, trace-element bioaccumulation is strongly controlled by the sediment-ingestion rate, which is itself a function of organic carbon (OC) content. We discuss the implications of these findings for the derivation of QSsediment and explore avenues for future research.
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