NANOTECHNOLOGY

Dangers come in small particles

Hundreds of nanotechnology applications are already in commercial production despite a huge health and safety question mark. Hazards looks at how an industry the safety authorities admit they know precious little about has been allowed to grow, unregulated, into the biggest thing since the microchip.

In the 1951 film classic “The man in the white suit,” Alec Guinness played a man who invented a fabric which never wore out and never got dirty. The story ended in humiliating disaster. Self-cleaning, long-lasting fabrics are among of the promises of the nanotech industry.

Danger! Dollar signs!

In the two decades since the birth of the nanotechnology revolution, it has been a strict case of small is beautiful. Dollar signs have blotted out the warning signs, and the technology has developed, as one observer put it, "at warp speed." This is a modern day gold rush - forget precaution, get to production.

When President Clinton launched the National Nanotechnology Initiative, now third in the research funding pecking order in the US behind the war on cancer and the Star Wars programme, he gushed about the potential. Tiny sensors would in the future speed through arteries detecting cancers at an early stage, exotic new lightweight materials would have be 10 times the strength of steel [1].

Media reports marvel at promised nano-based cancer cures and desktop nanomachine factories. The European Commission talked this year of "atom-scale 'nano-robots' that can be injected in the human body to cure diseases, electronic 'nano-chips' that can store and process much more information than today's microchips, 'nano-fibres' for better and always-clean clothes, and 'nano-materials' for high-performance coatings, for instance in aircraft and space ships."

The whole world caught the nanotech bug, quietly ignoring the early but serious question marks over safety. In May 2004, the European Commission put the industry's value today at Euro 2.5 billion worldwide. By 2011, it could hit the US$1 trillion mark.

According to a July 2004 TUC briefing: "Despite the fact that there are very few practical applications for nanotechnology at present, it is already a huge industry with almost £2 billion spent on research and development worldwide last year. Within the UK there is around £100 million of public money being spent on developing the technology over the next five years and a further £200 million likely to be invested by the private sector." [2]

In 2003 there were reports that Mitsubishi Chemical in Japan had begun construction work on a facility to manufacture hundreds of tonnes of "nano-tubes" each year. The US space agency NASA is scaling up production. A US Senate hearing in 2003 heard that most of the Fortune 500 companies now have nanotechnology programmes. Household names and major employers in the UK - IBM, ExxonMobil, DuPont, Hewlett Packard - all have had major programmes operational for years.

Production not protection

The journey from nanoscience emergence to commercial exploitation was travelled at dizzying speed - carbon nanotubes were first produced in a lab in 1991. By 2000 they were in commercial use as sports stadium flood lights.

In the US, the epicentre of the nanotech revolution, this upturn in commercial exploitation predated the creation in February 2004 of a nanotechnology health and safety research programme, run by the government's safety research agency NIOSH. It has still to issue a promised "best practices" guide however.

In the UK, attention to safety has been more sluggish still. On 29 July 2004, the Royal Society and the Royal Academy of Engineering announced the findings of a UK study of the safety of nanoparticles and called for new rules to guard against dangers to health and to the environment [3]. In October, HSE's Health and Safety Laboratory will host an international conference on workplace nanotech risks in Buxton. For now though, it's business as usual.

Already hundreds of nanotechnology-based products are on the market, from new computer displays to self-cleaning windows, from wrinkle creams to wrinkle-resistant pants. We might not know for certain whether nanotech will make you sick, but industry knows it can certainly make you rich.

And our own safety watchdog knows it too. In the introduction to a March 2004 paper prepared for the Health and Safety Commission (HSC), the Health and Safety Executive's chief scientist, Paul Davies, notes: "In the absence of complete and robust evidence of the risks HSC/E must work with stakeholders to promote and assure risk management of this technology without unnecessarily stifling innovation and wealth creation." [4]

As the organisation charged with ensuring the health of the workforce, many would argue that concerns for "innovation" might be better left to other agencies, and HSE resources would be more appropriately spent arguing the "health" and not the "wealth" case.

Wealth and safety

In May, the European Commission published its blueprint, Towards a European strategy for nanotechnology, "to help Europe to become world leader in the rapidly developing field of nanotechnology - the science of the infinitely small" [5]. The policy focuses on research and development, and calls for more investment in nanotechnology "to realise wealth generating products and services."

An EC news release accompanying the new research strategy does say it "also highlights the need to identify and address safety, health and environmental concerns associated with nanotechnologies and to promote risks assessment procedures at all stages of the technology's life cycle" [6]. But this is a real-life, real-time industry that is in place and is growing and unregulated.

HSE's Paul Davies suggests in his briefing it might stay that way for some time. He argues that a "precautionary approach" could hamper the development of nanotech-based safety technology and "would also earn the opprobrium of the government, which is strongly committed to the development of nanotechnology." Instead, a "Provisional Information Note" published in early 2004 says "control strategies should be based on the principle of reducing exposure to as low a level as is reasonably practicable" [7].

Reasonably dangerous

Applying the same control strategy you might apply to, say, grass cuttings or sugar dust to nanotechnology would guarantee widespread ill-health in the nanotech workforce if exposures were found to be anything other than low risk. This is a point not lost on John Howard, head of the US government's safety research body NIOSH.

He told a May 2004 conference: "Very little is known currently about how dangerous nanomaterials are, or how we should protect workers in related industries. Research over the past few years has shown that nanometre-diameter particles are more toxic than larger particles on a mass basis. The combination of particle size unique structures, and unique physical and chemical properties, suggests that a great deal of care needs to be taken to ensure adequate worker protection when manufacturing and using nanomaterials."

Howard added that nano products in development "are so far from our current understanding that we can not easily apply existing paradigms to protecting workers." [8]

By late July 2004, HSE had, belatedly, shifted to a more precautionary stance. The finalised information note, Nanotechnology: Horizons scanning information [9], says "as the risks arising from exposure to many types of nanoparticles are not yet completely understood, control strategies should be based on a principle of reducing exposure as much as possible."

Nonetheless, this is an information note, not a law, is not legally binding and is not evidential. Nanoparticles are still not subject to the more stringent controls that have seen many industrial substances banned outright and others, for example substances that can cause cancer, subject to special and more exacting regulations.

But while some existing workplace safety regulations may be an ill-fit, some don't fit at all. Getting a new substance onto the market is normally regulated by the Notification of New Substances Regulations 1993 (NONS). But nanotechnology uses structural, smaller, variants of common industrial substances. Its properties might be utterly different to its non-nano namesake, but it still would not require notification.

Real cause for concern

Nanotech safety was an obsession of sci fi geeks long before the safety boffins twigged there might be problem.

Although fears that runaway self-replicating "nanobots" would one day reduce the world to a "grey goo" have subsided, a runaway industry is exposing workers - maybe 2 million will be directly employed in the industry within 15 years - to an array of substances not adequately covered by existing exposure standards or governed by existing regulations on new substances.

The HSE briefing acknowledges "there can be considerable uncertainty in any assessment of the health and safety risks because of lack of knowledge about the hazards. Similarly there may be also a lack of knowledge about the effectiveness of risks control measures." [4]

The evidence we do have, however, suggest real concerns about human and environmental health effects and should have been sufficient to justify a halt in the nanotech clamour until we had a better idea of the risks and how to control them.

Jim Thomas, an Oxford-based programme officer with the technology watchdog ETC, writing in The Ecologist in February 2004, revealed that US and other regulatory agencies are "privately admitting they have made a mistake in letting nanoproducts onto the market without safety studies, and are looking for ways to tweak existing regulations" [10].

A July 2004 ETC report [11] says only in recent months have governments on both sides of the Atlantic "reluctantly conceded that current safety and health regulations may not be adequate" for nano materials. "Ironically, they are talking about the need to be proactive, failing to admit that they are already at least one decade late: nanotech products are already commercially available and laboratory workers and consumers are already being exposed to nanoparticles that could pose serious risks to people and the environment."

According to Thomas: "Only a handful of toxicological studies exist on engineered nanoparticles, but not-so-tiny red flags are popping up everywhere."

Toxic warnings

In his May 2004 "Nanowatch" column in The Ecologist, Thomas points out that the first ever scientific conference on nano-toxicity, Nanotox 2004, only took place in January this year [12]. He lists "Ten toxic warnings" including NASA research in 2003 showing nano-tubes produce a more toxic response in rats than quartz dust and claims by top UK toxicopathologist Vyvyan Howard that that nano-particles can cross the blood-brain barrier in humans and gold nano-particles can move across the placenta from mother to fetus.

According to Vyvyan Howard and ETC, nanoparticle toxicity is more related to their size than to the material from which they are made; while the reduction in size confers a variety of interesting and potentially profitable properties to substances, it can also confer unforeseen toxic properties. And they have high mobility not just within the body but getting into the body, by ingestion, inhalation or absorption through the skin [13].

Gold is a case in point - usually considered inert, it is highly reactive at the nano-scale. Similarly, titanium dioxide, one of the most commonly used substances in nanotechnology. Generally considered a relatively benign "nuisance dust" in normal industrial uses, it may have far more worrying properties in its nano applications.

The report of a March 2004 European Commission workshop, "Mapping out nano risks", looked at "the implications of these 'technologies of the tiny' for public health, health and safety at work and the environment" [14]. The findings of this workshop were in sharp contrast to the clamour for nano products encouraged and financed elsewhere in the Commission.

The EC report warned that "some engineered nanoparticles produced via nanotechnology may have the potential to pose serious concerns" and that "adverse effects of nanoparticles cannot be predicted (or derived) from the known toxicity of bulk material." The experts recommended "striving for the elimination whenever possible and otherwise the minimisation of the production and unintentional release of nanosized particles."

The new asbestos?

The ETC report notes that there has been a long tradition of ignoring early warnings until the bodies are piled high, pointing to examples including tobacco, PCBs, radiation, benzene and the biggest industrial killer of all time, asbestos. For asbestos, the parallels may not end there.

A June 2004 report from the European Union sponsored Nanoforum notes "some scientists have already compared nanotubes with asbestos in terms of risks and danger. For example, Dr Wiesner at Rice University pointed out that carbon nanotubes resemble asbestos fibres in shape: because they are long and needle-like." [15]

It was 100 years before asbestos companies and their insurers claimed they were "crippled" by asbestos liabilities so couldn't not pay asbestos victims compensation for deadly diseases. For nanotechnology, the problem may start much earlier in the life of the industry. Reinsurance company Swiss Re has already warned that uncertainty about risks from nanotoxicity and nanopollution meant there was insufficient information to offer insurance on the industry [16].

Its 10 May 2004 report, Nanotechnology: small matter, many unknowns, notes: "Specialist circles and society at large have neither solid knowledge derived from the past nor a suitable method for definitely assessing the consequences of any changes that may arise in the future."

It adds: "There are indications that certain nanomaterials are potential health hazards. The danger is most probably not of an acute but of a chronic nature, and it could be some time before it manifests itself. That is where the real risk for insurers lies, and the comparison with asbestos should be seen in this light."

Nano particles can kill you

Two factors could make nanoparticles a particularly serious occupational risk. Firstly their size alone could present hazards; secondly their massive surface area may adsorb other toxins that can then be transported into the body.

And evidence already exists to make this more than theory. Before nanotechnology became an industry, there was workplace and environmental pollution on a nano scale. Pollution from power plants, incinerators, cement kilns and diesel engines all contain "ultrafine" airborne particles that fall in the right size range. These particles are attributed with thousands of pollution-related deaths each year - perhaps 60,000 per year in the US alone. A California study suggests that these ultrafines are 10 to 50 times more damaging to lung tissue than larger particles [17].

The point was echoed in October 2003 by Professor Ken Donaldson of the University of Edinburgh, who warned that "the development of nanotechnology is predicted to improve our lives, but these very small nanoparticles look to have considerable potential to cause harm to the lungs.

"Already, the damaging effects of air pollution in cities looks like it is driven mostly from traffic-derived nanoparticles."

When he looked at the effects of pure carbon and pure titanium dioxide, very common chemicals in both traditional and nanotech industrial production, he found larger particles caused no damage to the lungs of rats, but when crushed to nano scale (less than 100 nanometres) they were potent causes of lung inflammation. A re-run of the experiment with styrene produced similar results [15].

In the US, government safety research body NIOSH says it has found a close correlation between potentially life-threatening beryllium sensitisation in workers and the concentration of nanometre-diameter beryllium particles.

According to the 24 July 2003 issue of Rachel's Environment and Health News [17], "current research shows that nanoparticles in the lung cause the formation of free radicals, which in turn, cause lung disease, and cardiovascular disease. Furthermore, nanoparticles carry metals and carcinogenic hydrocarbons deep into the lung, where they exacerbate asthma and other serious breathing problems."

There are concerns that nanoparticles may also cause lung fibrosis and possibly Alzheimer's. Rachel's warns of the risks of ramping up the industrial production of nanoparticles similar to those old-style ultrafines already established to be prolific killers. It concludes: "Clearly, in the case of nanoparticles, we have reasonable suspicion of harm, and we have some remaining scientific uncertainty. There we have an ethical duty to take preventive (precautionary) action. If there ever was a proper time to invoke the precautionary principle, this is it."

The sentiment is echoed in the July 2004 TUC nanotechnology factsheet [2], which says: "Nanomaterials should be treated just like any other serious health risk." It adds: "For unions that means seeking to ensure that the production and use of nanoparticles is done within a contained process so that employees are not exposed to any potential unknown risk."

TUC concludes: "It is important that unions act now to ensure that we do not have a rerun of the asbestos tragedy where hundreds of thousands of people were exposed to a killer dust that even today kills over 3,000 people a year."

Insurance company Swiss Re concludes the highest levels of safety protection are justified. Its report notes: "Presumably, nanoparticles must be handled with the same care given certain bio-organisms or radioactive substances. Adequate protective measures, such as a nao-compatible 'glove box', will probably have to be developed to ward off possible dangers." [16]

References

1. Rachel's Environment and Health News, No. 772. The Revolution, Part 1, 26 June 2003 Rachel's Environment and Health News, No. 773. The Revolution, Part 2, 10 July 2003

2. Nanotechnology. TUC factsheet, July 2004 and news release

3. Royal Society and the Royal Academy of Engineering report, 29 July 2004, and news release

4. Managing the risks from nanotechnology. A paper by Paul Davies, HSE chief scientist, HSC, 22 March 2004. Paper to the 6 April 2004 Health and Safety Commission meeting [pdf]

5. Towards a European strategy for nanotechnology, European Commission Communication, 12 May 2004.

6. Creating new knowledge in nanotechnology and turning it into better quality of life, competitiveness and jobs, European Commission news release, 12 May 2004.

7. Nanotechnology information note, version 0.9 [Annex 4, pdf]. Annex to reference 4.

8. Howard: Nanotechnology represents an "exciting challenge" for EHS, Occupational Hazards, USA, 7 May 2004.

9. Nanotechnology. HSE information note. Horizons Scanning Information Note No. HSIN1, July 2004.

10. Jim Thomas. Nanotech, The Ecologist, February 2004.

11. Nanotech: Unpredictable and un-regulated, ETC, news release, 8 July 2004. . Nanotech news in living colour: An update on white papers, red flags, green goo (and red herrings), ETC Communique no.85, 8 July 2004.

12. Jim Thomas. Nanowatch, The Ecologist, May 2004.

13. Nanotech under the microscope: Small is beautiful, but super-small particles may be a health risk. Utne, pages 15-16, July-August 2004.

14. European Commission, Nanotechnologies: A preliminary risk analysis on the basis of a workshop organised in Brussels on 1-2 March 2004 by the Health and Consumer Protection Directorate General of the European Commission, 2004.

15. Benefits, risks, ethical, legal and social aspects of nanotechnology, 4th Nanoforum Report, June 2004.

16. Nanotechnology: small matter, many unknowns, Swiss Re news release, and full report, 10 May 2004

17. Rachel's Environment and Health News, No. 774. The Revolution, Part 3: Ultrafines, 24 July 2003

Resources

ETC group - action group on erosion, technology and concentration.

US National Institute for Occupational Safety and Health nanotechnology and health topic page.

Nanotechnology and nanoscience. Royal Society and Royal College of Engineering website.

Cordis nanotechnology website, European Commission.

Nanoforum.org European Nanotechnology Gateway.