Safe as sunshine?

Far from being a knock to the nanotechnology industry, recommendations that nanoparticles be safety tested could give the UK an edge if we establish a uniform toxicology screening system.

The suggestion that imposing stricter controls over a fledgling field such as nanotechnology could help the UK steal a march on its competitors may seem laughable. But some researchers now believe the country could gain a vital lead in the emerging sector by developing a uniform toxicity screening system to assess the safety of nanoparticles.

As more companies, their employees and customers come into contact with nanotechnology-based processes and products, such a test could help the sector avoid comparisons with earlier disastrous developments such as asbestos.

Nanoparticles are already present in large numbers in the air from natural sources and as a result of combustion and vehicle exhaust emissions. Manufactured nanoparticles are currently used for applications such as titanium dioxide filters to ultraviolet in sunscreens.

At the scale of a billionth of a metre, materials have different properties from their parent, hence their ability to have numerous beneficial applications from targeted drug delivery in the body to the development of miniature, super-fast computing systems. However, the sector has for some time been the target of environmental activists, including those who campaigned successfully against GM food, who claim that technological development has sped ahead of safety.

The Royal Society and Royal Academy of Engineering’s report on nanotechnology, published in July, concluded that while most nanotechnologies pose no new risks there are still uncertainties about the potential effects on human health and the environment of manufactured nanoparticles and nanotubes.

The report recommended that, though production of nanoparticles and nanotubes should not be halted, because of their novel properties they should be treated and tested as new chemicals. Therefore, when new applications arise, safety testing should show that the novel properties of nanoparticles have been taken into account. However, no uniform method of testing the materials has been established, and attempts to do this are finding that funding is hard to come by.

The Royal Society’s report recommended that the UK Government should fund a programme of research to understand the effects of nanoparticles on humans and the environment, providing around £5-6m each year for a decade. This money would be used to support an interdisciplinary centre to research nanomaterials’ toxicity in the built and natural environment. But there is no guarantee of any such funding. The government is due to announce its response to the report later this year, but it refuses to be drawn on what this will be.

One academic is taking the matter into his own hands. Prof Ken Donaldson, lung toxicology expert and professor of respiratory medicine at Edinburgh University, has called for the development of a new discipline, nanotoxicology, to address the knowledge gaps concerning the interaction between nanoparticles and the human body.

He believes that while nanotechnology is vital, future acceptance depends on untangling science and science fiction through development of a system enabling industry to test new nanoscale materials.

If the UK can be first to develop a uniform testing scheme this could give us an edge in developing new technology. However, support has not been forthcoming.

‘When it came to looking at the toxic effects of silica, we depended on the US for research and followed their lead. I’m sure we don’t want to do that again,’ Donaldson said. ‘We are hoping to set up a service for industry called Nanoscreen which will offer comprehensive screening for new materials. It shouldn’t prove to be too expensive, but we are having trouble finding venture capital to start it up.’

In the meantime, his laboratory has been drawing together research money from a variety of sources. It hopes that if the government decides to take the Royal Society’s recommendation on-board, it will be positioned as an ideal site for any national test centre.

Despite the vast amount of money going into developing nanotechnology, setting up a toxicology testing system in the US may even be slightly behind the UK.

‘There is no call for uniform testing in the US so far – we don’t even have a uniform way to describe materials,’ said Ronald F. Turco of Purdue University. He is principal investigator in a project that aims to investigate the interaction between carbon-based manufactured nanoparticles and the environment. His group has been awarded grants, totalling $2m (£1m), from the US National Science Foundation and Environmental Protection Agency.

‘The only other active research programme I am aware of is at Rice University in Texas. I am hoping there will be around 10-20 more projects such as mine coming in the next two years. Even so, the budget will still be less than 10 per cent of the country’s total nanotech spend.’

Donaldson believes the UK has the expertise to seize the advantage from this. ‘We did a lot of work on PM10 [airborne particles from sources such as exhaust fumes that can penetrate the lungs. They have been linked to cardiovascular problems]. Many of the substances in PM10 are not normally harmful, so our idea was that the problem lies with the properties of ultra-fine particles, or in other words nanoparticles. We actually started to follow the nanoparticle trail 10 years ago.’

He is concerned that inhaled nanoparticles may be able to travel from the nasal nerves to the brain in the same way as viruses. This must be investigated if trust in the technology is to be established, he said.

‘People keep asking whether this is another GM and if there should be a moratorium,’ he said.’ However, each time you walk in the street you inhale millions of nanoparticles from diesel soot. We know these affect susceptible people only. Problems won’t apply to all materials. Nanotubes, for instance, aren’t very readily airborne, so inhalation shouldn’t be a problem with them.’

A well-developed test could help clear the air over what is and isn’t safe, enabling the whole nano-industry to fulfil its obvious potential.