The Health Protection Agency’s Centre for Radiation, Chemical and Environmental Hazards (CRCE) at Chilton, Oxfordshire, UK is to be the site of a new center for experimental toxicology research examining possible health effects of human exposure to nanoparticles: the National Nanotoxicology Research Centre (NNRC). The Agency is collaborating with five United Kingdom universities and the Medical Research Council’s (MRC) Toxicology Unit to develop the centre and its research programme. The Agency is adapting its existing aerosol inhalation research facilities, at a cost of more than £300,000, to allow a programme of experimental work on nanomaterials.
Knowledge of the possible interactions between nanomaterials and the human body is developing rapidly . NNRC will focus, initially, on the physical chemistry of nanoparticles and the behaviour of nanomaterials that enter the body via the lung and skin. Methods for producing aerosols of nanomaterials and measuring their properties, such as size distribution and concentration in air, will be developed and subsequent work will examine biological pathways taken by nanomaterials within the body.
A CRCE paper presented to the HPA Board in June described some of the industrial and toxicological developments underpinning the new centre’s creation. On the one hand, the CRCE paper explains, nanotechnology is likely to be one of the most important technological developments of the present century, yielding materials with physico-chemical properties that are valuable in electronics, in optoelectronics , in imaging systems used for medical diagnostic work, in cosmetics and in food preparations. While questions about the safety of these materials has led to the rapid growth of the new discipline of nanotoxicology, “& nanomaterials do not have entirely new toxicological properties,” the paper points out. “The key discoveries [of nanotoxicology research] have been that nanomaterials may reach parts of the body inaccessible to larger particles and that they tend to be more active than larger particles when activity is expressed on a ‘per unit mass’ basis.”
On the other hand, “The problem is not quite as simple as this”, the paper states. “The effort needed to characterize adequately nanomaterials under investigation and to identify the most appropriate measurement to express dose should not be underestimated. & Nano-materials may be able to gain access to parts of the body which larger particles cannot reach and thus might produce novel effects”. Experimental work involving injection of carbon nano-tubes into the peritoneal cavity of rats, for example, has already given rise to speculation that long, thin, insoluble carbon nano-tubes that are biopersistant may have toxicological properties similar to those of asbestos fibers, the CRCE paper notes.
A programme of international collaborative work on the safety of manufactured nanomaterials, being carried out as part of the OECD Chemicals Programme, is being coordinated in the UK by the Department for Environment, Food and Rural Affairs with input from other agencies including the Health and Safety Executive (HSE), the Environment Agency (EA) and the HPA.