Is nanotechnology a health timebomb?
By Paul Marks Emerging nanomaterials need to undergo urgent testing to assess their effects on health and the environment, the UK’s Royal Commission on Environmental Pollution said in a report released this week. It says nanotechnology-based products are hitting the market without being properly assessed for safety – and that’s a risk too far. But there are safety rules for all consumer products, aren’t there? Yes, but because nanomaterials are often made using chemicals like silver and carbon that are considered safe when used on a macro scale, the commission says they are slipping under the regulatory net when used at the nanoscale – without any consideration of the potentially adverse physical or chemical effects their novel nanostructures may have on people, animals, and the environment. What does the commission want? The commission is calling for the European Union to extend its regulatory regime for chemicals (REACH) to properly assess nanomaterials and their unique properties. In the UK, they want the Department of the Environment, Farming and Rural Affairs (DEFRA) to develop and undertake tests on products that contain nanomaterials, and develop gadgets that detect, for instance, nanomaterials like carbon nanotubes when they become airborne. “We have no means of detecting buckyballs or nanotubes in the environment right now,” says John Lawton, the RCEP’s chairman. Haven’t we been here before? Yes. But since 2004 when the Royal Society and Royal Academy of Engineering first said that a programme of research was necessary to ensure the safety of nanotech products, the field has moved on in leaps and bounds. “The rate of nanotechnology innovation now far outstrips our capacity to respond to the risks,” says Lawton. The RCEP thinks the arrival of products in our high streets means it’s time to reiterate the need for safety tests – as the earlier call fell on deaf ears in government. It also wants to avoid polarising public opinion, as happened with genetic modification. How many novel technologies are we talking about? The number of patents filed on nanomaterials worldwide by 2006 reached 1600 – and that growth has continued exponentially. According to the Project on Emerging Nanotechnologies in Washington, DC, there are at least 600 products on the global market that claim to contain a nanomaterial as a key ingredient, he adds. What kind of products contain nanomaterials? Well, the range is broad – and there could be health and environmental problems with any of them. They include sunscreens, cleaning products, anti-odour treatments for clothes, cosmetics, smart plastics, ceramics, self-cleaning glasses, composites, carbon-fibre-based textiles and other products containing nanotubes and buckyballs. Which ones are causing concern? All of them, to some extent. But the commission singled out two. “Nanosilver” – a bactericide which slows the formation of odour-forming bugs in clothes like socks, underpants and T-shirts. The second is a textile comprising spun fibres made from carbon nanotubes that could save the clothing industry a fortune by making clothes that don’t need dyes – their thread diameter dictates their colour through refraction effects. How might these products cause harm? “Nanosilver is biocidal to a remarkable extent – it’s extremely toxic to microorganisms,” says Lawton. In fact, it will kill twice the number of bacteria that bleach can. When flushed into water courses, no-one knows what could happen. It could stop the biochemical reactions that make your local sewage-processing plant work. Or it may damage aquatic life – buckyballs have already been shown to cause brain damage in fish. There have been reports that the carbon fibres in clothing could produce asbestosis-like lung diseases, and that spilled nanotubes could damage ecosystems. Why not just ban nanotech products? The RCEP thinks the advantages to society of nanotechnologies are too great to lose. “On balance there are no grounds for a blanket ban,” says Lawton. Instead, he simply wants a major increase in the amount of testing to assess risk – prioritising the materials that may present the greatest risk to the environment and human health. “Research gaps need to be addressed urgently, especially given the long lead times involved in developing and putting in place testing arrangements that will inform regulatory and legislative processes,” he says. More on these topics: