The possibility that wider exposure to anti-microbial agents in food contact materials (FCMs) may contribute to heightened bacterial resistance was highlighted as an area of concern for the UK-based body. It also said the accumulation of nanosilver in the environment should be scrutinised and the development of bespoke recycling procedures considered.
The IFST made its comments in its response to the European Food Safety Authority’s (EFSA) guidelines on the potential risks of nano-applications in food and feed published in January 2011.
The independent group said it was important that the EFSA document suggest the need for full toxicity data on engineered nanomaterials (ENM) used as composites in FCMs even where there is no evidence for migration of these particles into food, or where levels of migration are low, it said.
The body added: “IFST considers that this is important because, although the direct use of these materials may not lead to significant ingestion of the particles, knowledge of the level of toxicity, or lack of toxicity, may be needed in order to assess the acceptable levels of migration.”
The organisation said it was “concerned” that a number of mineral ENMs were being used, or put forward for use, as anti-microbial agents in food contact materials. It called for more research on the consequences of their release into the environment and declared this should be evaluated when considering their use in food applications.
The IFST said the use of antimicrobial agents was potentially important in the future – particularly in light of the spread of antimicrobial resistant microorganisms.
“If there is to be a use for such antimicrobials in the medical area in dressings, treatment of wounds, or generally in coating of medical implants, surgical instruments or hospital surfaces, then the IFST believes one should avoid widespread low-level exposure, which could lead to bacterial resistance to these materials,” said the body.
This issue should also be taken into account when considering the use of antimicrobials in supplements, or in directly-applied coatings for natural food products to prevent spoilage
Whole life concerns and specialised recycling
Crucially it raised the issue that production and disposal of these materials may eventually lead to increased exposure to the nanoparticles and urged that the possible consequences of this be explored.
Consideration of the ‘whole life’ aspects of encapsulated nanoparticles should be taken into account in their use or regulation, said the IFST.
It noted there was already evidence that the increased commercial use of nanosilver had led to a rise in the level of silver in streams and rivers. But it added that most nanosilver particles were removed during sewage treatment and converted into less reactive and more stable silver sulphite nanoparticles.
The IFST raised the possibility that disposal of food contact materials containing nanoparticles – and their subsequent breakdown - could lead to the release of more reactive forms into the environment.
The body cited evidence that nanoparticles can be transferred up the food chain once released into the environment and suggested the development of specialised recycling procedures be considered as part of the risk assessment.