Introduction: The regulatory importance of mineral oil hydrocarbons
Mineral Oil Hydrocarbons - MOH are one of the most important groups of chemical contaminants found in food contact packaging materials, especially in recycled paper and cardboard packaging. MOH can be divided into two main fractions: MOSH (Mineral Oil Saturated Hydrocarbons – Saturated Mineral Oil Hydrocarbons) and MOAH (Mineral Oil Aromatic Hydrocarbons – Aromatic Mineral Oil Hydrocarbons). The European Food Safety Authority (EFSA) has scientifically proven that MOSH accumulates in the liver and spleen and can lead to chronic toxicity; The MOAH faction, on the other hand, has genotoxic and carcinogenic potential, especially in its 3-7-ring aromatic components. Under the European Union's Packaging Regulation (PPWR), the controls on the contamination of MOH in packaging that come into contact with food are further intensified, and the manufacturers are given clear obligations in this regard. Nano-Test Labor Services carries out MOSH and MOAH analyzes in compliance with GLP principles with the internationally recognized LC-GC-FID technology and provides our customers with reliable quantitative data and an assessment of compliance with legal regulations.
Chemical definition and toxicological profile of MOSH and MOAH
Mineral Oil Hydrocarbons are a complex mixture of numerous hydrocarbon compounds that occurs when refining crude oil. Depending on the chemical structure and toxicological properties, they are divided into two main fractions. The following table compares the chemical definition, the toxicological profiles and the typical sources in the packaging of the MOSH and MOAH fractions:
| Property | MOSH (saturated mineral oil hydrocarbons) | MOAH (aromatic mineral oil hydrocarbons) |
|---|---|---|
| Chemical structure | Straight-chain (N-alkanes), branched (isoalkanes) and cyclic (cycloalkanes) saturated hydrocarbons | Hydrocarbons containing one or more aromatic rings; Highly alkylated benzene derivatives and polycyclic aromatic compounds |
| Carbon number range | C10 – C50 (Analysis range typically C10–C35 or C10–C50) | C10 – C50 (Analysis range typically C10–C35 or C10–C50) |
| Toxicological concerns | Enrichment in the liver and spleen (granuloma formation), chronic inflammation; classified by EFSA as a “potential risk to human health”. | 3-7-ring aromatic compounds can bind to the DNA; Potential for genotoxic carcinogenicity; classified by EFSA as a “high-priority health risk” |
| Typical source in packaging | Recycled paper/cardboard (newspaper inks), mineral oil-based process chemicals used in the production of fresh paper, printing inks, adhesives, wax coatings, jute and sisal fiber batch oils | |
Regulatory Framework and Applicable Limits
Although no legally binding specific migration limit (SML) has been established at European Union level, there are recommended thresholds and surveillance recommendations published by various Member States and EFSA. The PPWR aims to close this regulatory gap and provides for stricter control of the occurrence of mineral oil hydrocarbons in packaging materials.
Current Recommended Limits
The following table summarizes the current limits recommended by various regulators and interest groups for MOSH and MOAH:
| Parameter | Reference / Source | Limit (mg/kg food or simulans) | Scope / Explanation |
|---|---|---|---|
| MOAH (C10-C35) | Federal Law on Food and Feed (LFGB) / 22nd Amendment Ordinance | 0.5 (not verifiable) | Binding national limit for paper and cardboard that comes into contact with food |
| MOAH (C10-C25) | German LFGB / 22nd Amendment Ordinance | 0.15 (not verifiable) | Additional limit specifically for the more volatile low molecular weight MOAH fraction |
| MOSH (C10–C16) | Technical Report of EFSA / JRC (2019) | 12 | Recommended low viscosity mosh fraction threshold and high migration potential |
| MOSH (C16-C35) | Technical Report of EFSA / JRC (2019) | Recommendation for monitoring and minimization | Mosh fraction with high molecular weight; Reduction of exposure is recommended due to the potential for accumulation in the body |
| Moah (all factions) | FoodDrinkEurope Guide for Packaging | 0.5 (to detection limit) | Limit value voluntarily adopted by industry; An undetectable level is sought |
Note: The above limits apply to materials that come into contact with food; The total concentration limits for the packaging itself may differ. With the entry into force of the PPWR, the setting of harmonized, binding limit values at EU level is expected. Nano-Test continuously follows developments in legislation and proactively informs its customers.
MOSH/MOAH analysis methodology in the Nano Test Laboratory
MOSH and MOAH analyzes are an analytical process that requires a high degree of technical expertise and requires reliable separation and quantitative determination of complex hydrocarbon mixtures. In the nano-test laboratory, this analysis is carried out using the internationally recognized reference method LC-GC-FID (liquid chromatography - gas chromatography - flame ionization detector).
LC-GC-FID system: analytical principle and workflow
The LC-GC-FID technique is a fully automated and highly precise analysis platform in which the MOSH and MOAH fractions are first separated by liquid chromatography (LC) and then analyzed each fraction by gas chromatography (GC) and Flame ionization detector (FID) is quantitatively determined. This procedure was validated in accordance with DIN EN 16995:2017.
The following table describes the individual steps of the MOSH/MOAH analysis in the Nano Test Laboratory in detail:
| Step | Process | Technical Details |
|---|---|---|
| 1. Sample preparation | Extraction | The packaging sample or migration simulant is extracted with a suitable organic solvent (hexane or ethanol/hexane mixture). Appropriate internal standards (e.g. 5-α-cholan, periles) are added to monitor the extraction yield and to correct matrix effects. |
| 2. LC fractionation | Separation of Mosh and Moah | The extract obtained is injected into a normal phase LC column. The silica gel column allows the MOSH fraction (saturated hydrocarbons) to pass, but retains the MOAH fraction (aromatic compounds) in the column. Subsequently, the MOAH fraction is eluted from the column by changing the composition of the mobile phase and transferred to the GC system. |
| 3. GC FID Analysis | Quantitative Determination | The MOSH and MOAH fractions originating from the LC are transferred separately into the GC column. With the help of a temperature program, the hydrocarbons are separated according to their carbon number. With the FID detector, all hydrocarbons are measured quantitatively. The MOSH and MOAH amounts are calculated in relation to the peak areas of the internal standards. |
| 4. Data evaluation | Group Integration and Reporting | In the chromatograms, the characteristic "humps" (insoluble complex mixture - UCM) of the MOSH and MOAH fractions as well as the sharp n-alkane peaks above are integrated. The results are divided into various carbon number fractions (e.g. C10-C16, C16-C25, C25-C35) and given in mg/kg. |
Quality control and method validation
The reliability of the MOSH/MOAH analyzes in the nano test laboratory is guaranteed by a comprehensive quality control protocol. The following table summarizes the most important quality control parameters that are applied during the analysis process:
| Quality Control Parameters | Application | Acceptance criterion |
|---|---|---|
| Blind sample | At least 1 per analysis series | Mosh and moah < loq; Laboratory Contamination Monitoring |
| Recovery Rate of Internal Standard | Is added to each sample (e.g. 5-α-cholestan, periles) | 70-120% for the MOSH internal standard; For the MOAH internal standard 50-120% |
| Control standard (mineral oil mixture) | At least 1 in each analytical series | Within ±20 % of Expected Concentration |
| Duplicate analysis | 1 of 10 samples each | Relative percentage deviation (RPD) ≤ 30% |
| Certified Reference Material (CRM) | If available, in every series | Within ±25% of the certificate value |
The integrated service approach of Nano-Test in MOSH/MOAH analyses
As a Nano-Test Labor Services, we do not offer MOSH and MOAH analyzes as individual tests, but as an integral part of the PPWR and food safety conformity process. Our service model consists of the following components:
| Service Component | Scope | Benefits for the customer |
|---|---|---|
| Regulatory consulting | Determination of which fractions (C10-C16, C16-C25, C25-C35) need to be analyzed | Cost optimization through the right test strategy; Avoidance of missing or unnecessary analyses |
| LC GC FID Analysis | Quantitative MOSH and MOAH determination with a fully validated LC-GC-FID system for the quantitative determination of MOSH and MOAH | Reliable and traceable results with the reference method recognized by the supervisory authorities |
| Group-based reporting | Breakdown and detailed presentation of results by different carbon number fractions (C10-C16, C16-C25, C25-C35) | Easier identification of the source of contamination (fresh fibers, recycled components, specific process chemicals) |
| Conformity assessment | Preparation of a declaration of conformity or non-conformity by comparing the results with the applicable national limit values (e.g. German LFGB) and the industry recommendations and the submission of a declaration of conformity or non-conformity | A clear and binding assessment of the legal status of the product |
| Technical documentation | Comprehensive, GLP-compliant analysis report and declaration of conformity (DOC) | Complete documentation for official applications and customer audits |
Especially for manufacturers who use recycled paper and cardboard packaging, MOSH/MOAH contamination is one of the most critical aspects of supply chain management. As a nano test, we not only provide analytical data, but also offer our customers technical advice on the root cause analysis for detected contaminants, supplier evaluation and functional barrier solutions.
In order to ensure the MOSH/MOAH conformity of your packaging exported to the European market within the framework of the PPWR and the relevant regulations and to carry out your mineral oil-hydrocarbon analyzes with a reliable and experienced partner, you can Contact our team of experts for detailed information about the accredited laboratory services and technical advice from Nano-Test.