Approaches for the determination of NIAS as a part of Safety-By-Design

Transcription

1 Approaches for the determination of NIAS as a part of Safety-By-Design M. Driffield 1, M. Garcia-Lopez 1, E.L. Bradley 1, P.T.K. Oldring 2 1 Fera Science Ltd, 2 Valspar Corp. malcolm.driffield@fera.co.uk

2 What can migrate from FCMs? Known ingredients such as monomers, catalysts, solvents, suspension media, additives, etc. IAS Known or unknown isomers, oligomers (arguably not NIAS), impurities, reaction products and breakdown products of these ingredients Possible contaminants from the manufacturing process such as recycled materials, irradiated products, etc. Contamination from indirect sources such as printing inks, external coatings, adhesives, secondary packaging, etc. NIAS

3 NMR integral value NIAS analytical workflow Initial discussions with Sponsors Sample preparation Extraction or migration experiments Analysis Data interpretation Reporting Identification Detection Quantification TIC vs. EIC? Concentration vs.

4 Detection of NIAS Instrumentation Generally nonselective detectors Little structural information on unknowns Limited MS information - unit mass resolution GC-MS with searchable libraries LC-MS infancy LC-HR-MS routinely used Accurate mass and high resolution Structural data from controlled fragmentation GC-TOF-MS provides access to HR-MS for volatiles and semivolatiles

5 Detection of NIAS - Software Limited useful software available Software designed for non-targeted analysis Much more information extracted from the data sets Advanced statistics allow comparison of complex data

6 Identification of NIAS Manual data interrogation Time consuming??? Analytical tools (hardware and software) including: HR-MS Accurate mass Isotope information Controlled fragmentation NMR Comprehensive userprepared databases Close working relationship between the Analytical Chemist and Coating Manufacturer

7 Quantification of NIAS Comparison of structurally similar substances to standards e.g. BADGE related substances using LC-FLD OM, %LMWF vs. TIC Some internal standards More internal standards Structurally related oligomer standards Standard addition Authentic standards if available NMR vs. LC-MS Universal detectors

8 State-of-the-art (2016): Safety-By- Design Guides product development to the most appropriate low risk solutions e.g. from a coatings company: Product Development Ideation Material Investigation Process Monitoring Chemicals of Concern Endocrine Activity Testing Toxicological Testing Migration Analysis International Food Contact & Chemical Inventory Regulatory Approvals

9 State-of-the-art (2016): Safety-By- Design - Profiling What is the effect of changing an ingredient or processing temperature or site of manufacture on the NIAS profile? For example using the advanced statistical methods to investigate NIAS variation from the same coating applied at different locations: Industrial application company A Industrial application company B Laboratory application A Laboratory application B Laboratory application C Laboratory application D

10 State-of-the-art (2016): Modified coatings In support of a petition for a new monomer (non-bpa epoxy) it was necessary to investigate oligomers related to that monomer Original coating Modified coating A modified coating was prepared Non-BPA epoxy monomer was substituted by BADGE whilst keeping everything else the same All masses detected in the modified coating and the original coating could not be related to the monomer of interest Original coating Modified coating

11 State-of-the-art (2016): Databases Analytical data can be compared to theoretical databases of accurate masses of oligomers and reaction products associated with starting materials and impurities below 1000 Da Can include retention time, structures, MS/MS fragment data Mass differences of +/- 5 ppm (parts-per-million of the accurate mass) or better Can contain tens of thousands of substances but each match needs sense checking Should consider simulant-oligomer interactions

12 State-of-the-art (2016): Migration into food Due to the complexity of measuring known substances directly in foodstuffs, solvents and simulants are frequently used For NIAS (where unknown substances are detected) this is even more challenging Food simulants are defined in plastics legislation to over-estimate migration into foodstuffs Foodstuffs have been examined to see if simulants do in fact over-estimate migration of monomers and oligomers Initial results reported here but the work is on-going

13 Migration into food: Experiments Foodstuffs packed in cans with a polyester coating (containing nadic acid), stored up to 3 years, were analysed for the presence of monomers and oligomers The same foodstuffs packed in non-polyester coated cans used as control samples Generic solvent extraction with minimal clean-up and LC-TOF-MS analysis Profiling software used to identify substances present in the extract from the polyester and not a component of the food Comparison to database of oligomers Concentrations estimated using polyester oligomer standard

14 Migration into food: Oligomers Solvent or simulant Processing conditions Acetonitrile 1 Room temperarure for 24 hours water o C for 2 hours followed by 515 days at 40 o C 10% ethanol o C for 2 hours followed by 515 days at 40 o C 50% ethanol 2 No retort days at 40 o C IPA = isophthalic/terephthalic acid NA = nadic acid MPD = 2-methylpropane-1,3-diol CHDM = cyclohexane dimethanol Food Green beans 1 Wax beans 1 Peas 1 Processing conditions sterilised and stored for 730 days at ambient sterilised and stored for 450 days at ambient sterilised and stored for 500 days at ambient Estimated concentration of oligomer (μg/6 dm 2 ) A B C D E F G H I nd nd nd 77 nd nd nd nd nd Estimated concentration of oligomer (μg/kg) A B C D E F G H I nd nd 6.9 nd nd nd nd [1] Fera data [2] Data from Paseiro-Cerrato et al. J. Agri. Food Chem. (2016) 64 (11) A = IPA+MPD B = NA+CHDM C = IPA+2MPD D = 2IPA+2MPD E = NA+MPD+CHDM F = IPA+CHDM+MPD G = IPA+NA+2MPD H = 2IPA+2MPD+CHDM I = IPA+NA+CHDM+MPD

15 Migration into food: Oligomers Solvent or simulant Processing conditions Estimated concentration of oligomer (μg/6 dm 2 ) A B C D E F G H I Acetonitrile 1 Ambient for 24 hours nd nd nd 77 nd 68 water o C for 2 hours followed by 515 days at 40 o C 10% ethanol o C for 2 hours followed by 515 days at 40 o C 50% ethanol 2 No retort days at 40 o C nd nd nd nd Food Green beans 1 Wax beans 1 Peas 1 Processing conditions Sterilised and stored for 730 days at ambient Sterilised and stored for 450 days at ambient Sterilised and stored for 500 days at ambient Estimated concentration of oligomer (μg/kg) A B C D E F G H I nd nd 6.9 nd nd nd nd [1] Fera data [2] Data from Paseiro-Cerrato et al. J. Agri. Food Chem. (2016) 64 (11)

16 Migration into food: Monomers Solvent/simulant Processing conditions Nadic acid concentration (μg/6 dm 2 ) Acetonitrile 1 room temperature for 24 hours nd (LOD = 1.7) Acetonitrile 2 40 o C for 24 hours 1.8 Acetonitrile 3 room temperature for 24 hours nd (LOD = 24) 50% ethanol days at 40 o C 19 50% ethanol o C for 1 hour 42 10% ethanol o C for 2 hours followed by 515 days at 40 o C 46 3% acetic acid o C for 1 hour 18 water o C for 2 hours followed by 515 days at 40 o C 3.0 Foodstuff Processing conditions Nadic acid concentration (μg/kg) Green beans 1 sterilised and stored for 730 days at ambient <5.0 (n = 6) Green beans 1 sterilised and stored for 730 days at ambient 5.6 (n = 6) Tomato sauce 1 sterilised and stored for 990 days at ambient <0.30 (n = 3) Diced tomatoes 1 sterilised and stored for 1050 days at ambient <0.22 (n = 4) Tomatoes + chillies 1 sterilised and stored for 1050 days at ambient <0.22 (n = 4) [1] Fera data [2] Data from Paseiro-Cerrato et al. J. Agri. Food Chem. (2016) 64 (11) [3] Data from another laboratory

17 Migration into food: Summary Whilst the results for this coating show that the simulants exaggerate monomer migration, it is clear that for the selected oligomers, simulants greatly over-estimated the migration into the foods tested

18 State-of-the-art (2016): LC-QTOF-MS Controlled fragmentation experiments can lead to more data on structural information of peaks Characteristic fragments related to the non-bpa epoxy monomer can be used to further assign related peaks Differentiation between linear and cyclic oligomers + H 3 C CH 2 + H 2 C CH 3 O + H 3 C CH 2 OH O CH 3 HO O CH 3 OH CH 3

19 NMR integral value Area State-of-the-art (2016): NMR Oligomer determination 120 AA TMA PA CHDM BD EG DEG PG HD HMP TMP NPG H2O MW PA+EG linear EG+PA+EG linear PA+EG+PA+EG linear PA+EG+PA+EG cyclic PA+EG+PA+EG+PA linear PA+EG+PA+EG+PA+NPG linear PA+EG+PA+NPG+PA+EG linear PA+PG+PA+PG+PA+PG linear PA+PG+PA+PG+PA+PG cyclic Concentration Extraction of a FCM with solvent 0.04 mg/6 dm Concentration Monomer functional group quantification 0.03 mg/6 dm 2

20 Summary Safety-By-Design is an integrated alternatives assessment program that guides the product development process to the most appropriate low risk solution Ever-advancing analytical instrumentation provides very powerful tools for determination of NIAS As instruments become more readily available and sensitivity increases there is the potential for more and more NIAS to be detected

21 Acknowledgements Julie Christy Antony Lloyd Jonathan Tarbin Patrick Hough Danny Chan James Donarski