Brussels, 22 Oct 2004
A review carried out by the UK Health and Safety Executive (HSE) of the occupational hygiene of individuals working in the nanoparticle production process has concluded that the risks of exposure have not been sufficiently assessed.
The study focused on processes for the deliberate development and manufacture of nanoparticle products, such as nanotubes, nanowires, and quantum dots. It analysed potential routes for human exposure, levels of exposure, control measures, and knowledge gaps and the ease with which they can be filled.
The HSE identified approximately 2,000 people in the UK currently working in universities, research centres and new nanotechnology companies who could potentially be exposed to nanoparticles in some form, and this figure could double within five years, it adds. The four main nanoparticle production processes are gas-phase, vapour deposition, colloidal and attrition, all of which could result in exposure through inhalation, dermal or ingestion routes.
From an occupational hygiene perspective, these processes are not too different to existing chemical production processes. For exposure by inhalation, protection methods already exist that should be effective against nanoparticles, but for dermal and ingestion exposure, current control methods based on personal protective equipment may not be as effective as they are for chemical production processes.
Worryingly, the HSE states that no information is available concerning workers' exposure to nanoparticles in the UK, but information from other powder handling processes suggests that exposures may be significant. 'In summary, we conclude that there is little evidence to suggest that the exposure of workers arising from the production of nanoparticles has been adequately assessed,' states the HSE.
Key knowledge gaps identified in the study include the absence of agreed definitions or descriptions for nanoparticles, which the HSE team suggests could either be based on their physical dimensions or behavioural properties. Progress in this area will be best achieved by building consensus, and the HSE is organising a workshop to discuss the issue.
Finally, the report finds that current knowledge of nanoparticle risks is not sufficient to provide accurate risk assessments. 'Risk assessment approaches will have to consider how best to use information which is currently available, and plan to collect new information,' it concludes.
To download the full report, please consult the following web address: