More research needed to fill nanotech knowledge gaps

A lack of plausible scientific evidence means that no general conclusions can currently be drawn on the safety of food and packaging derived from nanomaterials, said Hong Kong’s Centre for Food Safety (CFS).

The food safety body also called for the development of a comprehensive code of guidance to evaluate the safety of the technology in food. It added that more general research into the field was vital to boost industry accountability as it was not currently possible to verify claims made by companies about the presence of NMs in foods.

The CFS identified the accelerating development of nanotech in FCMs and food as the trigger behind conducting its risk appraisal. The study aimed to review the basic principles, application and the potential health implications associated with the use of nanotechnology in the food sector.

No agreed definition

Nanotechnology deals with structures sized between approximately 1 and 100 nanometers in at least one dimension, said the agency, noting that no internationally agreed definition currently exists.

The report said: “A clear and internationally harmonised description of the technology would help to define the scope for safety assessment and regulation on the application of nanotechnology in food.”

The CFS highlighted packaging as having the largest uptake of the technology in the food sector – citing current examples of nano-enhanced FCMs as PET beer bottles with a nano-clay gas-barrier and polypropylene food containers with nano-silver for antimicrobial protection.

In food formulation, nanoencapsulation is currently the second largest area of nanotechnology application in the sector. The technique is used to harnessa controlled delivery system for food ingredients and additives in processed food and can be used to mask unpleasant flavours and protect ingredients from degradation.

But the agency also noted that while “the concept of nanodelivery systems can offer the benefit to enhance the absorption, uptake and bioavailability of nutrients and supplements, it also has the potential to alter the distribution of the substances in the body”.

Neither safer nor more dangerous

One of the issues raised by the report – Nanotechnology and Food Safety – is that not enough is presently known about the effects of NMs on the human body. It added that methods for detection and description of NMs in food also are not readily available as yet.

“In many instances, claims about the presence of NMs in food products could not be verified and people have to rely on information provided by the industry, producers and marketing organisations,” said the CFS.

But the body stated that no general conclusion could presently be reached on the safety of nanofood.

“At present, there is no tenable evidence that food and food contact materials derived from nanotechnology is any safer or more dangerous than their conventional counterparts,” said the CFS. “Neither is there any evidence to prove that consumption of nanomaterials is detrimental to human health."

An agency spokesman said the World Health Organisation (WHO) had recommended that the potential health and environmental risks of nanoscale materials be assessed before they are introduced into food. The UN bodies had also called for innovative and interdisciplinary research that could lead to novel risk assessment strategies for the application of nanotechnologies in food, he added.

The agency vowed that it would continue to scrutinise international trends in nano safety and noted that no standards safely guidance on NM had been developed.

"There is currently no comprehensive guidance developed particularly for the safety assessment of NMs in food,” said the spokesman. “Regulatory controls vary from country to country. The CFS will continue to monitor closely international trends regarding the application of nanotechnology in food products, discussions on safety issues, and the latest developments for possible follow-up action."