What are Non-Intentionally Added Substances – NIAS?
NIAS are chemical compounds which may be present in materials but have not been added for a technical reason during the production process. Their presence in food contact materials is often challenging for food contact materials producers. NIAS may arise from the following:
- Impurities originating from the manufacturing process
- Reaction intermediates formed during the polymerisation process
- Decomposition or reaction products formed during manufacture and use of food contact materials (FCM)
- Contaminants from recycling or irradiation treatments
What are the current regulatory guidelines concerning NIAS?
Regulation EU 10/2011 requires NIAS and non-listed substances to be risk assessed by the manufacturer in accordance with internationally recognised scientific principles – identification and measurement of the non-intentionally added substances is necessary.
How do you undertake NIAS assessment?
Different methodologies for testing exist but we advocate an analytical approach which includes:
- Screening the finished article using headspace/GC/MS to look for volatiles
- Solvent extraction GC/MS to look for less volatile substances
- An examination of formulation
- Migration testing using food simulants such as ethanol/water mixtures and iso-octane
- Incorporating internal markers to estimate levels
- Analysis by high temperature GC/FID and GC/MS.
- LC/MS multimode for picking up very polar, less volatile substances. LC/CAD for estimating levels
What are your methods of hazard evaluation?
We look for existing authorisations via Decernis regulatory intelligence and perform a toxicological review of databases - we utilise Toxtree to assign Cramer Class and any carcinogenicity/genotoxicity alerts. We also evaluate structurally similar compounds.
Can the Threshold of Toxicological Concern (TTC) be applied to NIAS?
You can assign human exposure thresholds that have a very low probability of causing adverse health effects to NIAS with known chemical structures. The EFSA opinion on TTC allows different thresholds to be set based upon structural activity relationships (SAR).
The TTC cannot be applied to unknown chemical structures and there are exclusions such as substances that bio-accumalate, proteins, metals (non-essential) and high potency carcinogens.
How is exposure to NIAS calculated?
The migration of NIAS into food/food simulants is measured and hazards of the identified substances are evaluated. To calculate exposure to NIAS we conduct migration and screening tests as well as modelling calculations. The (C)EDI is calculated and compared against an ADI (if available), where the ADI has been derived from toxicological data. The conventional EU exposure model is 60 kg person eating 1 kg food per day all wrapped in the same packaging (special provisions for children). However, in some cases a more refined estimate of exposure may be obtained by the use of FACET (Flavourings, additives food Contact materials Exposure Tool) which was developed under the EU 7th Framework Program.
What are some common problems encountered with NIAS risk assessments?
Problems can include:
- Substances that cannot be easily identified may require more expensive analytical techniques
- The possibility of carcinogens and creating a strategy to deal with them
- A lack of agreed analytical approach and coverage of methods
- Obtaining formulation details (in some cases)
Smithers Pira has expert knowledge of food contact regulatory requirements around the world. We offer a comprehensive range of migration testing and consultancy to help you demonstrate regulatory compliance or register new food contact substances. We also provide expert analytical testing and investigation to solve problems associated with contaminants, taints, packaging performance and other issues.
Find out more:
Contact Ian Cooper >
Non-Intentionally Added Substances >
Investigations and Chemical Analysis >
Webinar: Intro to EU Legislation on Food Contact Plastics (EU Regulation 10/2011) >