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Enhancing/extending the scope of pesticide multi-residue methods employed in the UK Pesticide Residue Committee programme - PS2537

Description
There is an ongoing expectation from consumers and the European Commission that regulatory authorities can undertake surveillance of increasing numbers of pesticides at ppb concentrations (around 0.01 mg/kg) in almost any food or feed sample.

Recent developments in chromatography-mass spectrometry techniques have underpinned significant improvements in the capability of laboratories to screen for hundreds of pesticides in individual samples. As a result of the successful outcomes of ongoing Pesticide Residues Committee (PRC) research and development programmes in recent years, the laboratories contributing to the UK PRC monitoring programme are currently analysing around 200 pesticides in each sample of fruit or vegetable. This represents a step change compared to 2006 in which the maximum number of residues tested was 129 [1]. This improvement has been delivered by analysing approximately 100 pesticides each by (Liquid ChromatographyTandem Mass Spectrometry (LC-MS/MS) and gas chromatography mass spectrometry (GC-MS) and has been achieved with no increase in the cost of the analysis. The next obvious step is to continue to evaluate the use of generic acetonitrile extraction procedures in combination with LC-MS and GC-MS technologies to further increase the number of pesticides that can be screened in the PRC programme. The real challenge for PRC laboratories is to achieve this target of 400 pesticides more cost effectively, using the minimum number of methods and appropriate analytical quality control. Therefore, PSD have requested research to be undertaken with an objective to inform on strategies for different approaches to integrated LC and GC multi-residue methods to answer the following questions;

i) Is it possible to undertake PRC surveillance for 300, 400 or 500 pesticides using integrated LC and GC multi-residue screens?
ii) What are the most relevant pesticides to include in an extension of scope of the PRC programme?
III) What analytical challenges do laboratories have to overcome to achieve these numbers of analytes?
IV) What are the best cost-benefits that can be obtained?

It is proposed to attempt to improve the robustness and extend scope of the QuEChERS acetonitrile extraction method by solving difficulties reported with the GC-MS analysis [3] and then to focus on the further development of LC-MS/MS methods. The initial aim is to increase the scope of the LC-MS/MS method to around 200 pesticides. The outcome of this research will be to demonstrate that it should be possible, using an integrated LC-MS (LC-MS/MS and GC-MS (GC-MS or GC-MS/MS ) approach, to increase the number of pesticides sought in the PRC to at least 300 during 2009. It is inevitable that all pesticides cannot be included in generic methodology and there will be an ongoing need for the development of alternative technologies [e.g. Time of Flight Mass Spectrometry (TOFMS)] and single residue methods to compliment multi-residue methods.

References
1) Annual Report of the Pesticide Residues Committee 2006 (http://www.prc-uk.org).
2) Amadeo Fernades Alba, Presentation; European Community Reference Laboratories (CRL) work programme scope and benefit for official pesticide residues laboratories; 4th Fresenius Conference on Pesticide Residues in Food, Frankfurt 9-10th July 2007.
3) CSL SID 5 report (2006) for Defra project PS2513; QuEChERS (Optimisation and Implementation of Low Cost Generic Extraction Procedures for Pesticide Residues in Food).

Objective
The Overall Project Objectives supplied by PSD were as follows;

To undertake research to inform on strategies for different approaches to integrated LC and GC multi-residue methods to answer the following questions;

• Is it possible to undertake PRC surveillance for 300, 400 or 500 pesticides using integrated LC and GC multi-residue screens?
• What are the most relevant pesticides to include in an extension of scope of the PRC programme?
• What analytical challenges do laboratories have to overcome to achieve these numbers of analytes?
• What are the best cost-benefits that can be obtained?


Therefore the proposed specific objectives of this project in Phase 1 are:

1) To attempt to overcome outstanding issues with problematic GC-MS pesticides reported in a previous project PS2513 [3] and difficulties experienced during routine surveillance. If successful this would facilitate wider implementation of the QuEChERS acetonitrile extraction procedure and maximise the cost savings from the use of a single generic extraction.

2) To attempt to increase the scope of the use of the QuEChERS acetonitrile extraction in combination with LC-MS/MS for the analysis of up to 200 pesticides.

3) To evaluate the literature on developments in pesticide multi-residue methods including QuEChERS to update the current project and direct future R&D.
Project Documents
• Final Report : Extending the scope of pesticide multi-residue methods employed in the UK PRC programme   (396k)
Time-Scale and Cost
From: 2007

To: 2008

Cost: £80,677
Contractor / Funded Organisations
Central Science Laboratory
Keywords
Agriculture and Food Chain              
Analysis              
Analytical Chemistry              
Analytical Quality Control              
Food Quality              
Food Safety              
Mass Spectrometry              
Method Development              
Monitoring and evaluation              
Pesticide Residues              
Public Health              
Residues Testing              
Fields of Study
Pesticide Safety