An analytical instrument manufacturer s perspective;

Transcription

1 An analytical instrument manufacturer s perspective; supporting the accreditation and training needs of food testing laboratories Sara Stead PhD sara_stead@waters.com Fera-JIFSAN Annual Symposium 13 th June Waters Corporation 1

2 Overview Food testing analysis requirements & challenges the big five The regulatory perspective? Technology solutions to solve real world challenges Case study 1; ASAP for rapid testing of export samples Demonstrating fitness for purpose Case study 2; Validation of a multi-residue method accordance with regulatory criteria Making the customer successful Supporting capacity building & training priorities 2013 Waters Corporation 2

3 Food analysis requirements? the big five Robust quantitative analytical tools Rapid multi-class screening Simplified extraction protocols Ease of operation Identification of unknowns 2013 Waters Corporation 3

4 Quantitative trace residue analysis What challenges do our customers face? Matrix & analyte complexity Validation & AQC requirements Sample type & extract preparation Compliance with regulatory performance criteria Ease of use & implementation 2013 Waters Corporation 4

5 Complying with the regulatory framework the day-to-day challenges Regulated market sector Regulations vary with geography Trade barriers? Permitted residue levels Authorised compounds, e.g. ractopamine Requirement to validate method performance & monitoring ongoing AQC Drive to harmonise the regulations globally (CODEX, WHO FAO) International standards for food safety Many countries choose to implement the criteria of the countries they export to EU has criteria for third countries 2013 Waters Corporation 5

6 Regulations may define the choice of analytical method employed Increasing potential for interferences Techniques suitable for screening assays Suitable for use as confirmatory assays for BANNED compounds Suitable for use as confirmatory assays for permitted compounds MS/MS LC/GC-MS LC-F LC-UV ELISA Microbiological Increasing ability to discriminate (selectivity) 2013 Waters Corporation 6

7 Instrument manufacturers role? Meeting the needs of the industry Regulatory Requirements? Permitted limits Banned residues Validation and AQC Informed product development via effective communication Current analytical challenges? Sample complexity Sensitivity Selectivity Speed of analysis Emerging risks? Residue scares Consumer safety Toxicological assessments Future directions and trends? Horizon scanning 2013 Waters Corporation 7

8 Deployment of technology solutions to solve complex analytical challenges 2013 Waters Corporation 8

9 Case Study -1 Strategy for rapid analysis 2011 plasticizer incident in food exports from Taiwan 2013 Waters Corporation 9

10 Background 2011 plasticiser incident in Taiwan Di(2-ethylhexyl) phthalate (DEHP): general purpose plasticizer used to make soft / pliable plastics Toxicity 20 times more toxic than melamine! Classified as class B2 (probable human carcinogen) Regulations Dissolved DEHP maximum level must not exceed 1.5 ppm International TDI between mg /60 kg adult May 2011 Taiwan FDA found DEHP in powdered probiotics Product recall, traced back clouding agent food additive Rigorous tests were carried out on six categories of food & beverages including: o o o o Sports, fruit and tea drinks Jam and jellies Food powders Health supplement tablets Rapid screen for the presence of DEHP using a simple technique with minimal sample preparation and no chromatographic separation was required 2013 Waters Corporation 10

11 Developing a solution to meet the analytical needs Direct sample analysis Fast analysis No sample prep No chromatography Solids & liquids Ambient ionisation Analytical requirements Detect specific compounds in complex samples Minimise risk of carryover Quick and easy to use Screen 1000 s food samples 2013 Waters Corporation 11

12 Export survey findings Monitoring for all 6 plasticizers in food samples 2013 Waters Corporation 12

13 Fruit jam desorption profiles 1 ppm spike (green) vs blank (red) DBP BBP DNOP Suspected positive sample DEHP DINP DIDP 2013 Waters Corporation 13

14 ASAP based rapid analysis Method highlights Simple & rapid screening of 6 plasticizers from sample preparation to analysis was achieved in <2 minutes per sample using ASAP coupled to tandem MS DEHP was successfully detected at 1 ppm in a range of food matrices An increase in lab productivity & efficiency due to the ease of sample preparation (direct sampling from the matrix) and shorter analysis times Fit for purpose, robust method 2013 Waters Corporation 14

15 Demonstrating fitness for purpose via method validation, AQC & proficiency testing 2013 Waters Corporation 15

16 Why is method validation necessary? Establish that the method is fit-for-purpose in accordance with regulatory criteria To ensure consistency of results between analysts/laboratories/countries To comply with quality system requirements (GLP/ISO 17025) Robust application of control methods (ongoing AQC) All of the above play a part in facilitating (international) trade 2013 Waters Corporation 16

17 CD 2002/657/EC approach to validation for vet drug residues Screening vs confirmatory methods Confirmatory analysis Quantitative method performance The Identification Point system Prescribed validation protocol and experimental design Specificity Repeatability Reproducibility Precision Recovery and trueness Calibration curve Robustness Storage stability Decision Limit (CCα) Detection Limit (CCβ) 2013 Waters Corporation 17

18 Current EU guidelines for pesticides analysis: SANCO/12495/2011 Guidance criteria for method validation & analytical quality control Covers the full analytical process from sampling through to reporting procedures Screening Detection Limit (SDL) must be calculated for each analyte within the scope of the method SDL is the concentration in matrix at which the analyte will be detected in 95% of samples Fit for purpose SDL = MRL for the majority of analytes Supports compliance with the accreditation standard ISO/ Waters Corporation 18

19 SANCO/12495/2011 performance criteria for pesticides Sensitivity in line with the relevant regulatory limits MRLs/ tolerances etc. Signal to noise ratio >3:1 Applicability of the screening method is defined by the false noncompliant (positive) and false compliant (negative) rates Tolerance 5% false negative rate Desirable 5% false positive rate (cost considerations) Identification Mass accuracy tolerance = 5 ppm and 2 diagnostic ions Mass resolution tolerance = 20k (FWHM) 2013 Waters Corporation 19

20 SANCO/12495/2011 (for pesticides) Identification requirements and future trend A variety of MS analysers and configurations including HR-MS are recognised with differing requirements for identification depending on the inherent analytical power 2013 Waters Corporation 20

21 Case Study -2 Validation of a multi-pesticide screening method in accordance with EU guidelines 2013 Waters Corporation 21

22 Generic Sample Preparation QuEChERS 15 g milled sample + 15 ml 1% HAc in MeCN Shake Add 6 g MgSO g of NaAcO Shake & centrifuge dspe: 1.5 ml supernatant mg MgSO mg PSA DisQuE QuEChERS (AOAC method) 10 different sample types 216 of the pesticides spiked at 0.01 and 0.05 mg kg -1 Shake & centrifuge Solvent exchange: 75% Water 25% ACN 2013 Waters Corporation 22

23 Chromatographic separation System Column Column temperature Flow Mobile phase ACQUITY UPLC I-Class ACQUITY UPLC BEH C18 50 mm x 2.1 mm, 1.7 µm 45 o C 0.45 ml/min (A) H 2 O (0.01M Amm. Acetate) (B) MeOH (0.01M Amm. Acetate) Gradient Time (min) % A % B Injection Volume: 5µL flow through needle injection 2013 Waters Corporation 23

24 Detection: Xevo G2-S QToF Ionization Mode ESI + (0.8 kv) Capillary voltage 1.0V Cone voltage 25V Desolvation Temperature 550 C Reference Mass Acquisition Range Leucine enkephalin [M+H] + = m/z Acquisition Rate 8 spectra/second Data Acquisition Acquire data-independent MS E data MS E scan (Low CE): 2V MS E scan (ramp CE): 10-45V 8 Spectra/Sec 2013 Waters Corporation 24

25 % Detection rate achieved 0.01 & 0.05 mg/kg per commodity Commodity %Detection rate 0.01 mg/kg 0.05 mg/kg Blank Grape Tomato Pepper Nectarine Pear Orange Melon Broccoli Apple Celery Mean Waters Corporation 25

26 Screening Detection Limits Two different samples for each commodity Commodities spiked with c.200 EU approved LC ammenable pesticides Analysis (ESI +ve mode) on 2 different days (>2 months apart) Apple, grape, tomato, pepper, nectarine, pear, onion, melon, broccoli celery and leek Screening Detection Limits 0.01 mg/kg 0.05 mg/kg Number of compounds detected 95% of the time % detection rate Waters Corporation 26

27 EURL Proficiency Test Scheme Screening methods (SM series) Series ID Year Matrix SM Mandarin SM Pear SM Leek Concentration range mg/kg Wide scope screening methods Only qualitative data requested for pesticides detected Target list of pesticides not provided 2013 Waters Corporation 27

28 EUPT results Automated data processing Sample ID Leek SM- 02 Mandarin SM- 03 Pear SM- 04 No. of targets No. of targets in database No. of target pesticides detected No. of FDs Detection rate (%) (No. of pesticides in DB) ESI + Processing parameters ± 5 ppm, ± 0.5 min, >100 counts, isotope m/z match (10 ppm), fragments 2013 Waters Corporation 28

29 Validation Overview Qualitative performance (screen) Detection rates typically 90% at 0.01 mg/kg and 95% at 0.05 mg/kg 80% pesticides have SDL 0.01 mg/kg, 90% have SDL 0.05 mg/kg %FD rate typically 5% across 10 matrices Quantitative performance Good recovery (mean % recovery = 92%, 186 pesticides in apple) Good linearity (mean R 2 = ) Good mass accuracy (<3ppm in matrix) Demonstration of fitness for purpose & applicability for routine surveillance 2013 Waters Corporation 29

30 Supporting laboratory capacity building & training needs to demonstrate compliance 2013 Waters Corporation 30

31 Training priorities developing laboratory capability Global context of food safety Analytical methods QA (validation & accreditation) Data analysis & interpretation Sampling requirements Metrology Laboratory management (LIMS, SDMS) Maintenance & troubleshooting May be addressed by face-to-face or online training 2013 Waters Corporation 31

32 A Global Network for Food Safety Training (capacity building) 2013 Waters Corporation 32

33 Benefits of capacity building? GAO Report: US foreign assistance with pesticide control will: o Decrease the likelihood that US consumers receive produce grown with pesticides lacking EPA tolerances for use on specific crops, o Help these countries avoid no tolerance pesticide violations o Prevent economic losses to exporters and US importers o Improve awareness and technical competency within that country Capacity building measures can be the first step in building assurances of efficacy of foreign food safety systems 2013 Waters Corporation 33

34 Summary Food analysis presents a complex analytical challenge! A variety of techniques are required adequately address these challenges Ease of implementation & robustness are critical to withstand the rigours of validation and ongoing AQC Instrument manufacturers can support the food industry Development of robust fit for purpose technologies capable of addressing today s challenges Provision of training and support Facilitating the sharing of information and contributing to establishment of analytical performance criteria 2013 Waters Corporation 34

35 Thank You for your attention Sara Stead 2013 Waters Corporation 35