Application of LC-MS for monitoring of substances in surface water under WFD

Transcription

1 Twinning Contract BG 06 IB EN 01 Strengthening of Surface Water Monitoring Network Operation Activity 3.3: Training on chemical analytical methods. Course on chemical analytical methods February 2009 Application of LC-MS for monitoring of substances in surface water under WFD Emanuele Ferretti National Institute of Health Dept. of Envronment and Primary Prevention Section of Inland Water Hygiene

2 Priority substances: legislation Strategy for dealing with pollution of water from chemicals is set out in Article 16 of the Water Framework Directive 2000/60/EC (WFD). A list of priority substances was adopted (Decision 2455/2001/EC) identifying 33 substances or groups of substances of priority concern in surface waters throughout the European Union due to their widespread use and their high concentrations in rivers, lakes, transitional, and coastal waters. This list will have to be reviewed every four years and updated as appropriate. The current list comprises mainly organic compounds including various pesticides, certain PAHs, benzene, halogenated solvents, flame retardants, a plasticiser, surfactants and antifouling agents as well as some heavy metals.

3 The identification of substances of priority concern Based on a simplified risk-based assessment procedure taking particular account of: evidence regarding the intrinsic hazard of the substance concerned, and in particular its aquatic ecotoxicity and human toxicity via aquatic exposure routes, evidence from monitoring of widespread environmental contamination, other proven factors, which may indicate the possibility of widespread environmental contamination, such as production or use volume and use patterns. For those priority pollutants measures shall be aimed at the progressive reduction and, for the subset of priority hazardous substances because of their high persistence, bioaccumulation and toxicity, at the cessation or phasing-out of discharges, emissions and losses.

4 Directive to protect surface water from pollution by chemicals (DIR 2008\105\EC) The proposed Directive will set limits on concentrations in surface waters of 41 dangerous chemical substances including 33 priority substances and 8 other pollutants that pose a particular risk to animal and plant life in the aquatic environment and to human health. This proposal aims at ensuring a high level of protection against such risks originating from those 41 substances by setting environmental quality standards (EQSs) at European level.

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8 21 - (EQS-AA) Environmental Quality Standard expressed as an annual average value (EQS-MAC) Environmental Quality Standard expressed as a maximum allowable concentration. Where the MAC-EQS are marked as "not applicable", the AA-EQS values are also protective against short-term pollution peaks since they are significantly lower than the values derived on the basis of acute toxicity For the group of priority substances covered by brominated diphenylethers (No. 5) listed in Decision 2455/2001/EC, an EQS is established only for pentabromodiphenylether For Cadmium and its compounds (No. 6) the EQS values vary dependent upon the hardness of the water as specified in five class categories

9 WFD - Specific pollutants Under the Water Framework Directive, Member States shall furthermore set quality standards for river basin specific pollutants identified in accordance with that Directive and take actions to meet those quality standards by Specific pollutants are defined as substances that can have a harmful effect on biological quality, and which may be identified by Member States as being discharged to surface waters in significant quantities. According to WFD compliance with EQSs for specific pollutants is part of the g p Q p p p ecological status assessment. WFD provides only an indicative list of such pollutants in Annex VIII including:

10 (1) organohalogen compounds and substances, which may form such compounds in the aquatic environment, (2) organophosphorous compounds, (3) organotin compounds, (4) substances and preparations, or the breakdown products of such, which have been proved to possess carcinogenic or mutagenic properties or properties, which may affect steroidogenic, thyroid, reproduction or other endocrine-related functions in or via the aquatic environment, (5) persistent hydrocarbons and persistent and bioaccumulative organic toxic substances, (6) cyanides, (7) metals and their compounds, (8) arsenic and its compounds, (9) biocides and plant protection products. Generally, candidates for specific pollutants will come from List II of the Dangerous Substances Directive (76/464/EEC), which is now integrated in the Water Framework Directive and will be fully repealed in 2013, or they will be chemicals identified as emerging issues.

11 UNCERTAINTY, LOQ and EQS According to ISO-DIS minimum performance criteria laboratories should demonstrate that the methods they apply to the analysis of priority substances and other pollutants for the purpose of compliance checking have U % (extended uncertainty) = 1/2 EQS LOQ (limit of quantification) = 1/3 EQS The comparability of monitoring results is of major importance for the usefulness and the acceptance of these monitoring requirements. EU Member States need to develop and to implement a quality-assurance/quality control (QA/QC) system to ensure that all monitoring results meet the desired levels of accuracy. Among these measures, participation in proficiency testing (PT) schemes plays an important role for ensuring the comparability of measurement data, and checking laboratory performance.

12 Analytical method for monitoring Any analytical method selected for the purpose of monitoring under Article 8 and Annex V of the Directive 2000/60/EC shall meet minimum performance criteria Annex V, paragraph 1.3.6, of Directive 2000/60/EC stipulates that methods used for the monitoring of type parameters shall conform to the international standards listed in that paragraph or such other national or international standards which will ensure the provision of data of an equivalent scientific quality and comparability; Accordingly, analytical methods that are not standardised but provide data of equivalent or better scientific quality and comparability than standard methods listed in Annex V, paragraph 1.3.6, of the Directive 2000/60/EC may be used for the purpose of the monitoring programmes.

13 Standard methods applicable to the analysis of priority substances and other pollutants in surface water for the purpose of compliance checking Priority substance a,b Standard method Principle Alachlor c EN ISO 6468: GC-ECD C Anthracene ISO 17993: 2002 HPLC-Fluorescence Detection Atrazine EN ISO 11369:1997 HPLC-UV EN ISO 10695: 2000 GC-NPD or GC MS Benzene EN ISO 15680:2003 Purge and Trap + Thermal Desorption ISO :1997 Headspace-GC-FID Cadmium and its compounds ISO :2003 ICP-MS Chlorfenvinphos EN 12918:1999 GC-FPD, GC-NPD, GC MS, GC-AED or GC-ECD Chlorpyrifos (-ethyl, -methyl) EN 12918:1999 GC-FPD, GC-NPD, GC MS, GC-AED or GC-ECD 1,2-Dichloroethane EN ISO 10301:1997 GC or Headspace-GC EN ISO 15680:2003 Purge and Trap + Thermal Desorption Dichloromethane EN ISO 10301:1997 GC or Headspace-GC-ECD or other EN ISO 15680:2003 Purge and Trap + Thermal Desorption

14 Standard methods applicable to the analysis of priority substances and other pollutants in surface water for the purpose of compliance checking Priority substance a,b Standard method Principle Di(2-ethylhexyl)phthalate (DEHP)d ISO 18856:2004 GC MS Diuron EN ISO 11369:1997 HPLC-UV DDT (4 Isomers)e EN ISO 6468:1996 GC-ECD Fluoranthene ISO 17993: 2002 HPLC-Fluorescence Detection Hexachlorobenzenee EN ISO 6468:1996 GC-ECD Hexachlorobutadienec EN ISO 10301:1997 GC-ECD or Headspace-GC-ECD or other EN ISO 15680:2003 Purge and Trap + Thermal Desorption EN ISO 6468:1996 GC-ECD Hexachlorocyclohexanee l h EN ISO 6468:1996 GC-ECD Isoproturon EN ISO 11369:1997 HPLC-UV Lead and its compounds ISO :2003 ICP-MS ISO 15586:2003 ET-AAS Mercury and its compounds EN 12338:1998 CV-AAS with Amalgamation EN 13506:2001 Atomic Fluorescence Spectrometry

15 Standard methods applicable to the analysis of priority substances and other pollutants in surface water for the purpose of compliance checking Priority substance a,b Standard method Principle Naphthalene ISO 17993: 2002 HPLC-Fluorescence EN ISO 15680:2003 Purge and Trap + Thermal Desorption Nickel and its compounds ISO :2003 ICP-MS EN ISO 11885:2007 ISO 15586:2003 ICP-AES* ET-AAS Nonylphenolsf yp ISO :2005 GC MS Octylphenol (4- (1,1,3,3Tetramethylbutyl)phenol) ISO :2005 GC MS Pentachlorophenol EN 12673:1998 GC-ECD or GC MS after derivatisation Benzo(a)pyrene ISO 17993: 2002 HPLC-Fluorescence Detection Benzo(b)fluorantheneg ISO 17993: 2002 HPLC-Fluorescence Detection Benzo(k)fluorantheneg ISO 17993: 2002 HPLC-Fluorescence Detection Simazinei EN ISO 11369: HPLC-UV EN ISO 10695: 2000 GC-NPD or GC MS

16 Standard methods applicable to the analysis of priority substances and other pollutants in surface water for the purpose of compliance checking Priority substance a,b Standard method Principle Tetrachloroethene th EN ISO 10301: GC-ECD or Headspace-GC-ECD or other EN ISO 15680:2003 Purge and Trap + Thermal Desorption Tetrachloromethane th EN ISO 10301: GC-ECD or Headspace-GC-ECD or other EN ISO 15680:2003 Purge and Trap + Thermal Desorption Trichlorobenzenesenes EN ISO 6468:1996 GC-ECD EN ISO 15680:2003 Purge and Trap + Thermal Desorption Trichloroethene EN ISO 10301:1997 GC-ECD or Headspace-GC-ECD or other EN ISO 15680:2003 Purge and Trap + Thermal Desorption Trichloromethane EN ISO 10301:1997 GC-ECD or Headspace-GC-ECD or other

17 a For the analysis of pentabromodiphenyl ether and C10 C13 chloroalkanes in water there is no standard method available. b The existing standards for the analysis of certain organochlorine pesticides (aldrin, endrin, isodrin, dieldrin, endosulfan, pentachlorobenzene), PAHs (benzo(g,h,i)perylene, indeno(1,2,3- cd)pyrene), ) and tributyltin compounds are not sensitive enough to conduct compliance monitoring. c Alachlor and hexachlorobutadiene are not within the scope of the standard but national monitoring laboratories reported that EN ISO 6468 may be used for the determination of these compounds. d Although the method is applicable to the analysis of DEHP in surface water and allows achieving sufficient low LOQ to conduct compliance checking in principle, many laboratories have serious blank problems and are hence, not able to meet the LOQ performance criterion (LOQ 30% EQS). e According to the results of a survey conducted within the Chemical Monitoring Activy LOQ low enough to allow compliance checking is difficult to achieve or even impossible ibl for DDT (due to the fact that 4 isomers have to be determined), hexachlorocyclohexane and hexachlorobenzene. f Although the method is applicable to the analysis of NP in surface water and allows achieving sufficient low LOQ to conduct compliance checking in principle, many laboratories have serious blank problems and are hence, not able to meet the LOQ performance criterion (LOQ 30% EQS). g Although benzo(k)fluoranthene and benzo(b)fluoranthene are mentioned in the scope of the standard LOQ low enough to allow compliance checking is difficult to achieve or even impossible.

18 LC-MS for monitoring of substances in surface water

19 LC-MS for monitoring of substances in surface water Pesticides (EDCs) DBPs (EDCs) Herbicides Hormonal residue (EDCs) Cyanotoxins Pharmaceuticals and Personal Care Products Organic compounds Drugs used in food producing animals

20 LC-MS High vacuum system Different Pumps Inlet Source Mass filter Detector Data System Sample Plate MALDI TOF Target ESI Quadrupole HPLC IonSpray Ion Trap GC FAB magnetic Solids probe LSIMS FTMS EI/CI CEM..

21 LC-MS soft ionization i techniques Electrospray / ionspray Laser ioni Matrice&campione MALDI (matrix assisted laser desorption ionization)

22 LC-MS: Single e triple quadrupole

23 MALDI TOF (Time Of Flight) Matrix assisted laser desorption-ionization (MALDI), time-of-flight (ToF), MS Sample (e.g.protein) embedded in matrix is ionised by laser Ions accelerated through electric field at different rates Lightest arrive first For protein For protein sequencing/identification of biological material (e.g. microorganism)

24 Pharmaceutical residues in water * * Toxicol. Lett., 131 (2002): 5 17.

25 Determination of pharmaceutical compounds in water by LC-MS.

26 LC-MS analyses of microcystins

27 LC-MS analyses of pesticide residues

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32 Tributyltin compounds The AA-EQS for tributyltin is significantly lower than the typical limits of quantitation (LOQ) for routinely applied analytical methods. The AA-EQS of 0.2 ng/l suggests a required LOQ of 0.06 ng/l whereas current commonly used analytical methodologies have typical LOQ in the 1 10 ng/l range. Need for further research to either improve the sensitivity of existing techniques, develop new practical methodologies or, perhaps, to utilise a compliance regime based on the analysis of a suitable biological receptor and take advantage of the associated biomagnification.

33 Pesticides EQSs were set for a number of pesticides including alachlor, atrazine, simazine, diuron, isoproturon, chlorfenvinphos, chlorpyrifos, endosulfan, trifluralin, hexachlorocyclohexanes (HCH), DDT, aldrin, dieldrin, endrin, and isodrin. The most widely used methods for the analysis of pesticides and their metabolites in environmental samples are based on GC-MS and tandem triple quadrupole LC-MS 2. LC-MS 2 is usually operated in the in the multiple reaction monitoring (MRM) mode by detecting specific MS/MS mass transitions of the molecules, resulting in increased selectivity. Isotope dilution, based on the addition of labelled internal standards prior to sample extraction, has proven to be a powerful quantitative analytical technique. Extraction of water samples, the most commonly used methods are solid-phase extraction (SPE) and liquid liquid extraction (LLE). Solid-phase microextraction (SPME) is less frequently applied. SPE methods are rapid, efficient (good recoveries and low detection limits), use less solvent than LLE and consequently reduce laboratory expenses. In addition, SPE methods can be automated t by using laboratory robotic systems that t do all or part of the sample preparation steps. SPE also can be combined on-line with LC-MS 2 detection. In addition, highly sophisticated techniques such as LC Q TOF MS methods have been reported for pesticide measurements in water.

34 Pesticides The more polar triazines (atrazine, simazine) and phenylurea herbicides (diuron, isoproturon) and the chloroacetanilide alachlor can be analysed by LC-MS. The method detection limits (MDLs) for the multi-compound pesticide methods based on SPE or LLE followed by LC MS 2 are usually in the range of 1 15 ng/l and thus suffice to meet the requirements of the WFD in most cases. However, AA-EQSs, in particular those for other surface waters, for endosulfan, hexachlorocylohexane and the sum of cyclodiene pesticides aldrin, dieldrin, endrin, and isodrin are significantly lower than the typical LOQ of routinely applied analytical methods. Pesticides without an aromatic structure like glyphosate, currently the most widely used herbicide, including its metabolites AMPA, and glufosinate can only be analysed by GC- or LC- MS methods after derivatisation.

35 Perfluorinated compounds (PFCs) Perfluorinated carboxylates and sulfonates are an emerging class of environmental pollutants, which are water-soluble and persistent. Perfluorooctansulfonate (PFOS) and perfluorooctanoate (PFOA) have been proposed as new priority substances of the WFD by the European Parliament. They have been found to be widespread in the aquatic environment. Since the WFD requires also the monitoring of other pollutants discharged in significant quantities in the river basins as already mentioned, the analysis of PFCs as river basin specific pollutants might be necessary in certain regions of Europe. LC-electrospray ionisation-ms i (LC-ESI-MS) and in particular LC-MS2 are the most common analytical techniques used for the measurement of PFCs. Also LC-TOF-MS has been proposed as a highly selective and sensitive method. Solid-phase extraction (SPE) is the method of choice for extracting PFCs from water, but also liquid liquid extraction (LLE) is suitable. A wide variety of SPE methods have been reported for sample extraction and clean-up of water samples. Different column types have been used, including purely hydrophobic (C18), mixed hydrophobic/polar p (e.g., Oasis HLB) and weak anion exchange (WAX)-type phases. Using these adsorbents, recoveries for short-chain PFCs with alkyl-chains of less than 6 carbon atoms, however, are insufficient.

36 Perfluorinated compounds (PFCs) The quality in PFC analysis has been improved considerably during the last years as demonstrated in recent laboratory intercomparisons organised within the PERFORCE project. The results of the first worldwide interlaboratory study on PFCs in water in 2005 showed poor performance with only a few laboratories achieving i satisfactory t results. Unlike this study, the 3rd interlaboratory trial on PFCs conducted in 2007 showed very promising results indicating that the majority of participating laboratories were able to analyse PFCs in the intercomparison i samples properly. The improvements compared to the first interlaboartory t study can mainly be explained by the use of common native and 13C-labelled PFC standards, but also attributed to better control of blanks and the wide experience gained by the laboratories during the last years.

37 Conclusions Reviewing the state of the art in monitoring chemical pollutants to assess water quality status has shown that approximately 75% of the 41 hazardous substances for which Europe-wide EQSs have been proposed can be reliably monitored in water with acceptable uncertainty when applying existing standardised methods, even though there are certain limitations in applicability and uncertainties in assessing the performance for some methods. Monitoring chemical pollutants in water encounters difficulties for some substances, in particular short-chain chlorinated paraffins (SCCPs), polybrominated diphenyl ethers (PBDEs), tributyltin compounds, certain organochlorine pesticides and six-ring PAHs, mainly for lack of validated, sufficiently sensitive methods that are applicable in routine laboratory conditions. The AA-EQSs for these compounds (except for SCCPs) are significantly lower than the typical limits of quantitation (LOQ) for routinely applied analytical methods particularly when taking the proposed minimum performance criterion LOQ less than 30% of EQS into account. There is an urgent need for further research to improve the sensitivity of existing techniques and to develop new practical methodologies, such us LC-MS-MS.