German safety body maintains doubts over nano silver

The Federal Institute for Risk Assessment (BfR) in Germany has called for further data on the safety of nano silver before it makes a final risk assessment.

The decision was made following a workshop held by the BfR between invited experts, from research and science, as well representatives from industry and associations.

The aim of the workshop was to discuss current risks, the availability of data and scientific studies on the area, and the possible need to take action for consumer protection against the risk.

Need for scientific data

“The decision confirmed the words of caution from the BfR, because the situation continues to be characterised by the fact that not enough secured scientific findings about the specific effects of nano-sized sliver particles are available,” said Dr. Andreas Hensel, BfR president.

Previously the BfR has published an official opinion, No. 24/2010, stating that nano silver might represent a toxicological effect profile because there are additional toxic effects which have not yet been fully identified.

European cosmetics industry body Colipa says that nano silver is used ‘sporadically’ in personal care formulations, mainly for use as an anti-microbial agent, and that such products have undergone a full assessment for safety.

Exisiting data is considered insufficient

However, the workshop highlighted the fact that so far there is only very limited data available that has assessed the material on the nano scale for its toxicological effects, and that the existing data is largely insufficient as it is incomplete.

The workshop also highlighted the fact that more recent studies have given clear indications of effects so far not yet known for silver, including pathological changes for tissues in the liver following oral and inhalative exposure, as well as physiological changes to specific organs.

The BfR also pointed out that there may be challenges in securing further studies and data on the health risks of nano silver because at present few industries are obliged to provide the public authorities with toxicological data on the subject at present, making the assessment process extremely difficult.

Friends of the Earth criticise nano silver

Last November, Friends of the Earth released a report that criciticed the use of nanotechnology in cosmetics and specifically drew attention to the end of the life cycle of nano silver as being problematic.

The organisation referenced research that suggests exposing sludge similar to that found in waste water treatment plants to nano silver particles led to a significant increase in the release of nitrous oxide.

The report explained that nitrous oxide is designated as a potent greenhouse gas and according to the United Nations Framework Convention on Climate Change, it is 310 times more effective in trapping heat in the atmosphere when compared to carbon dioxide over a 100 year period.

According to the organisation, the public should be made aware that avoiding products containing nano silver could reduce their carbon foot print.