Differentiating Resin Oligomers from MOSH/MOAH Hydrocarbon Resins, - - PowerPoint PPT Presentation

• Representing European based producers of resins
• Members of the European Chemical Industry Council (Cefic).
• HARRPA exists since 1991
• 15 member companies in Europe for a total yearly production of more than 1 million tons and a total turnover around 1,5 billion euros
• >30 production sites in Europe / employing >3,000 people

Hydrocarbon Resins, Rosin Resins and Pine Chemicals Producers Association

Differentiating Resin Oligomers from MOSH/MOAH Annual Conference FEICA, Riga, 12-14 September 2018

Henk-Jan de Jager Ruud van der Eerden Michaela Hofbauer

From-Farm-to-Fork

Food safety

Content

• Introduction
• What are Resins?
• What are Mineral Oils?
• What is the issue?
• 2D vs 1D GC: C9 and DCPD Resins
• Take-away messages

Plant growth Harvesting & Storage Transport Food processing & Packaging Retailer Consumer Crop protection Environmental contamination: accidental Processing: Machine oils Processing: Machine oils Packaging: Migration

• Produced from feedstocks that originate from pine trees
• The main building block used for rosin resins production is rosin (Colophonium)
• Terpene resins are polymerized from terpenes
• Rosin can be chemically modified through disproportionation, hydrogenation,

dimerization and/or fortification with organic acids

• Esterification of rosin with alcohols yields rosin esters

→ Rosin and terpene resins are not mineral oils!

What are … Resins?

Rosin and Terpene Resins are low molecular weight, high Tg polymers

Tall Oil Rosin Gum Rosin Wood Rosin

Crude oil: “…… cracking operations generate olefins (alkenes and cycloalkenes), …. Olefins are not present in crude petroleum.”

National Research Council. 1985. Oil in the Sea: Inputs, Fates, and Effects. Washington, DC: The National Academies Press, p.25.

• Crude oil fractions (naphtha) are fed to steam-crackers to produce ethylene, propylene as well as other products
• Monomers for hydrocarbon resins (olefins and di-olefins) are also created in the steam cracker process
• Monomers are identified according to their chemical nature (e.g. C5, C9, ...)
• Resins oligomers in hydrocarbon resins are formed as integral part of the resin polymerization process,

Hydrocarbons resins are obtained by polymerizing hydrocarbon monomers such as C5, C9 and DCPD.

C5 C9

What are … Resins?

Hydrocarbon resins

Oligomers Mw

DCPD

→ The monomers used to make hydrocarbon resins are not present in crude oil, but synthetically produced! Hydrocarbon resins are not mineral oils!

Concawe (Mocrinis Workshop, 2017) Mineral oil is a generic term used to group several petroleum derived liquids, manufactured by atmospheric and vacuum distillation of crude oil followed by further refinement through extraction, dewaxing and hydrogenation or other treatment.

What are … Mineral Oils?

According to EFSA opinion (2012): “hydrocarbons containing 10 to about 50 carbon atoms, where the crude mineral oils remain by far the predominant source of the mineral oil hydrocarbons considered, but equivalent products can be synthesised from coal, natural gas or biomass.”

• Significant difference between definitions
• A clear mineral oil definition is missing

Source: Concawe Mocrinis II Workshop (Brussels, 17-18 October 2017); https://www.concawe.eu/wp-content/uploads/2017/10/DEF_C_MM_digital.pdf

Definitions

• Mineral oil expressed as MOSH (Mineral Oil Saturated Hydrocarbons) and MOAH (Mineral Oil Aromatic Hydrocarbons)
• Identified as a potential source of food contamination, primarily through recycling of paper
• Mineral oils sparked controversy about the health hazards of MOSH/MOAH species (bioaccumulation, carcinogenicity)
• Consumers groups (e.g. Food Watch) expressed their concerns
• Wish to monitor the situation and develop an inventory as a basis for possible regulatory action
• Regulations may be pursued that limit the MOSH/MOAH content of packaging materials
• Consequences for food producers, food packagers and their suppliers

What is the issue?

Contamination of mineral oils in food is a matter of food safety!

Action EC: Recommendation (EU) 2017/84: Monitoring of mineral oil hydrocarbons in food  Generate reliable and comparable results  Determine the possible source of mineral oil  European Reference Laboratory (EU-RL) develops guidance for suitable test method

• Guidance stipulates the use of 1D GC analysis
• Test method suitable if you accept that all C10-C50 is MOSH/MOAH – even products of biological or vegetable
• rigin
• Listed components in the Union list of the Plastics Regulation might contribute to MOSH/MOAH levels
• Demonstrated (*) that 1D GC does not sufficiently distinguish between mineral oils and other low molecular

weight hydrocarbons

• If MOSH/MOAH levels are regulated, an improper analytical method could lead to the dismissal of evaluated and

approved food contact materials

(*) Lommatzsch, M., Biedermann, M., Grob, K., & Simat, T. (2016, October 17). Analysis of saturated and aromatic hydrocarbons migrating from polyolefin-based hot-melt adhesive into food. Food additives & contaminants, Part A, 33(3), 473-488

Implementing EU Recommendation

Challenges due to selectivity of the test method

Analytical technique: 1D GC

Real world: recycled cardboard

Analytical technique: 1D GC

1. Measures all hydrocarbons: Insufficient selectivity for mineral oil constituents and non-mineral oil constituents. 2. Broad unresolved hump  too complex for ID purposes: Too many peaks (=substances) Severe overlap of peaks (resolution) Ideal world: clean GC

What is the issue?

Resin oligomers are not MOSH / MOAH!

Need to develop an improved analytical technique that can distinguish between resin oligomers and MOSH/MOAH

What is the issue?

Analytical technique: 2D GC Feedstock Tall Oil Rosin Rosin Terpene DCPD DCPD/C9 C9 C5 PMR Modification / Type Non-H2 Glycerol Ester α,β-Pinene mixture Non-H2 Non-H2 Non-H2 Non-H2 AMS / Styrene Glycerol Rosin Ester Partial H2 Glycerol Ester Terpene Phenol resin Partial H2 Partial H2 Partial H2 Aromatic Non-H2 Penta Rosin Ester H2 H2 H2

HARRPA

• Initiative to develop a technique to distinguish between MOSH/MOAH and resins (Laboratory Lommatzsch & Säger)
• Create awareness of the difference between MOSH/MOAH and resins among stakeholders.

Resin families selected by HARRPA for 1D GC and 2D GC analyses

1D GC: C9 resins Resin Saturated Hydrocarbons Resin Aromatic Hydrocarbons H2 Partial H2 non H2 H2 Partial H2 non H2 C10-C50 Recycled cardboard - Extract

2D vs 1D GC

• Overlap of MOSH/MOAH with resin oligomers could result in false positives!

Analytical technique: 2D GC

Recycled cardboard – Extract Food print of a mineral oil

Main border cyclic MOSH Monoaromatics Di-aromatics Tri-aromatics Poly-aromatics Internal standards MOSH

Orientation in 2D GC Hydrocarbon separation based on:

• 1D GC Volatility
• 2D GC Volatility and Polarity

2D vs 1D GC

A. Dimers B. Trimers C. Tetramers Non H2 partial H2 H2

C

2D GC: C9 resins Saturated hydrocarbons Unsaturated hydrocarbons

2D vs 1D GC

Mineral Oil footprint

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2D GC: H2-DCPD resin

• A. Trimer
• B. Tetramer
• C. Pentamer
• D. Hexamer

2D vs 1D GC

Saturated hydrocarbons Unsaturated hydrocarbons

• 1D GC is intended to determine (un)saturated hydrocarbons, but is limited for mixtures of hydrocarbons from

different sources.

• Concentrations of hydrocarbons in different fractions can be determined, but a qualitative evaluation is hardly

feasible.

• 2D GC identified and differentiated the vast majority of the resin oligomers from mineral oil hydrocarbons.

This calls for a reliable and adequate (2D GC) analysis Correct Interpretation is key Possibility to trace source of contamination HARRPA strongly recommends that 2D GC is accepted and endorsed for MOSH/ MOAH analysis EU Recommendation 2017/84 stipulates:

• Generate reliable and comparable results of the monitoring
• Determine the possible source of mineral oil

Conclusions

2D vs 1D GC

Take-away messages

1. Resins are not minerals oils! 2. The 1D (JRC method) is supposed to focus on finding MOSH and MOAH – false positives have been identified 3. HARRPA with Lommatzsch lab evaluated 2D GC

• Differentiation between resins and MOSH/MOAH
• HARRPA encourages stakeholders to use 2D GC

4. 2D GC technology is more sophisticated and should be endorsed as a complimentary method 5. Our industry (HARRPA) is committed to continue working with all stakeholders on this to further develop a suitable method

HARRPA Position paper on Resin and mineral oil analysis in food contact materials:

http://www.harrpa.eu/images/Publications/HARRPA_MOSHMOAH_201712.pdf

Acknowledgement to Laboratory Lommatzsch & Säger

Backup Slides

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Source: Concawe Mocrinis II Workshop (Brussels, 17-18 October 2017); https://www.concawe.eu/wp-content/uploads/2017/10/DEF_C_MM_digital.pdf

What are Mineral Oils?

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Concawe definition mineral oil

MOSH: Mineral Oil Saturated Hydrocarbons

• chromatographic measure of alkane content of a mineral oil.

MOAH: Mineral Oil Aromatic Hydrocarbons

• chromatographic measure of aromatic content of a mineral oil.

MOSH and MOAH are not substances, but constituents in mineral oil!

What are MOSH / MOAH?

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Concawe definition MOSH & MOAH

Who are the stakeholders?

Overview situation

HPLC-GCxGC- FID/MS (2D) HPLC-GC- FID (1D)

2D GC Mineral Oil

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• This 2D GC chromatogram of

mineral oil mix

• 2D GC chromatogram of the MOAH

fraction of a mineral oil mix

MOAH fraction

• SIC technology allows to show on the chromatogram, species made of selected fragments only
• Fragment 91 m/z (tropylium ion) can be used to visualize most of the monoaromatics or aromatics

containing only single aromatic rings

• Fragment 117 m/z characteristic for monoaromatics with an indane basic structure
• Species showing same fragments and eluting in different locations have different chemical structure

Single Ion Chromatogram differentiation (SIC)

Both examples show main elution areas between the 1- and 2-line as expected

C9 resin

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The C9-oligomers are assembled from different mono-aromatic-units, which can be displayed by fragments 91 and 117 m/z. Contrary to MOAH, the oligomers from C9 resins do not contain condensed aromatic ring systems as basic structure

• C9 dimers and trimers, whether partially- (dotted circles) or non-H2 (solid line circles), show main elution areas

below the 2-line.

• Significant overlapping with monoaromatic MOAH cannot be observed.
• C9 Oligomers are distinguished from MOAH species

C9 resin

Single Ion Chromatogram differentiation (SIC)

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• Similar differentiation study is done on C9 modified DCPD resins :
• Aromatic-modified DCPD resin oligomerss (CPD/C9 dimers – hexamers), whether partially- (solid

line circles) or non-H2 (dotted circles), show also main elution areas below the 2-line.

• A significant overlapping with monoaromatic MOAH cannot be observed .
• C9 modified DCPD Oligomers are distinguished from MOAH species

Single Ion Chromatogram differentiation (SIC)

C9 modified DCPD resin

HARRPA – contact details

The mailing address of the organisation is: Cefic / HARRPA Avenue E van Nieuwenhuyse 4 B - 1160 Brussels (Belgium) www.harrpa.eu For further assistance, please contact: Joël Wilmot Tel +32.2.676.72.88 email: jwi@cefic.be Karin Coiffard Tel : +32 2 676 74 93 E-mail : kco@cefic.be

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