This report gives background information on current applications of nanotechnology for providing clean drinking water. It includes both technologies still being developed in the laboratory and those that have reached the market.

New water filters and purification systems are now being designed with nanomaterials including carbon nanofiltration membranes, and nanocatalysts such as iron and silver. Such technologies could help countries in the developing world cope with the pressures of a growing population and stressed water services.

The review features research into water nanotechnologies from around the world, with special attention to those developed and marketed in India's water sector. It points to key challenges that may hinder their impact in providing clean drinking water to the poor, and identifies technologies that could be further researched and developed.

This report from PLoS Medicine argues that nanotechnology has a role in the development of low-income countries. The authors survey 85 experts worldwide and rank the top ten nanotech applications most likely to benefit developing nations. They outline how these applications can help meet the Millennium Development Goals. The paper calls for an initiative to identify "grand challenges" in nanotechnology for global health, which since the publication of this paper are now underway.

This follow-up paper, from the Journal of Nanotechnology Online, provides an in-depth look at the way poor countries engage with nanotechnology. It analyses why some developing nations are ahead of others in nanotechnology progress, and the challenges some less-developed countries face in shoring up nanotechnology capacity. It also investigates nanotechnology patent activity and assesses country participation in nanotechnology policy dialogues – for instance, China is a frontrunner in filing nanotech patents yet it is absent from policy discussions.

This essay by Chunli Bai, executive vice president of the Chinese Academy of Sciences (CAS), explains the reasons behind the rapid progress of nanotechnology in China. A key factor, says Bai, has been "extraordinary" government support for the field since the early 1980s, which led to the creation of research institutes and significant grant money. But, cautions Bai, public communication on nanotechnology research, and ongoing monitoring and assessment of nanotechnology risks is needed.

This report, published by the Meridian Institute describes the growing interest of developing countries including Brazil, China, India and South Africa, in nanotechnology. The ways nanotechnology applications could solve health, sanitation, and pollution problems and provide faster, cheaper information and communication technology are outlined. The challenges of using and developing nanotechnology for and in developing nations including the roles and responsibilities of different stakeholders are also discussed.

The Meridian Institute says nanotechnology can play a role in achieving the UN Millennium Development Goals. As a result, rich nations should dedicate a reasonable portion of their overseas development assistance to nanotechnology.

Mohamed Hassan at the Academy of Sciences for the Developing World (TWAS) argues that the nanotechnology boom will not lead to a divide between developed and developing countries due to the transformation of 21st century global science. Hassan says Brazil, China and India are swiftly developing nanotech capabilities. Instead, he warns of a South-South divide as poorer nations struggle to catch up. To avoid this, Hassan recommends that developing nations create networks between universities and research centres to share nanotech expertise.

This Nanomedicine paper reviews a range of strategies based on nanotechnology that are currently being used or tested to improve HIV/AIDS treatment and prevention. The authors review nanomedical advances in antiretroviral therapy, gene therapy, immunotherapy, vaccines and microbicides.

They conclude that nanotechnology promises great improvements in all of these areas but they warn that the field still faces many challenges including the toxicity of nanomaterials, their stability in physiological settings and the question of how to mass-produce them.

This report, written for the Meridian Institute by a team of scientists from South Africa and Sri Lanka, describes the general issues facing projects aimed at improving access to clean water in the developing world, as well as the specific challenges facing nano-based projects.

The authors describe a number of water treatment devices that incorporate nanotechnology, including nanofiltration membranes, attapulgite clays and zeolites, nanocatalysts, magnetic nanoparticles and nanosensors. More importantly, they outline potential opportunities associated with these technologies, and possible risks.

The paper includes two case studies of projects designed to improve access to clean water — one in Bangladesh based on a conventional approach using sari cloth to remove cholera from water, and one in South Africa that incorporates a nanofiltration membrane.

This paper from the Meridian Institute describes a range of well-known and field-tested conventional approaches to removing contaminants from water as well as the current crop of nanotechnologies that could enhance existing — or develop new — water treatment technologies.

For each approach or potential product the authors give a short description of what it is and who has developed it, and report on the product's effectiveness in removing contaminants, the amount of water it can treat, and its cost and ease of use. They also include summary comparative charts of conventional versus nano-based treatments.

Conventional approaches covered include various types of filters, ultraviolet radiation, chemical treatment and desalination. Nano-based water treatments covered include carbon nanotube-based technologies, nanofiltration membranes and devices, nanoporous materials and clays, zeolites, nanocatalysts and magnetic nanoparticles.

This scientific article, written by researchers at Rice University in the United States, describes how magnetite (iron) nanocrystals — or 'nanorust' — can be used to remove arsenic from contaminated water. The authors describe the discovery of unexpected magnetic interactions between nanoparticles of rust that mean they can be easily extracted from water using a hand-held magnet.

Iron is well known for its ability to bind arsenic and the researchers' experiments show that by suspending the nanoparticles of rust in arsenic-contaminated water, arsenic levels were reduced to well below accepted standards for drinking water.

This feature article from Nanowerk, written in collaboration with scientists, provides a short introduction to the role nanotechnology could play in resolving water shortage and quality issues.

The authors describe how nanotechnologies are being used in water filtration, especially nanotechnology membranes incorporating carbon nanotubes and dendrimers. They also examine how nanotechnologies and materials such as zeolites, carbon nanotubes and biopolymers can be used to remove, reduce or neutralise heavy metals and other contaminants that pose a threat to human health. And they briefly discuss the issue of using nanotechnology to develop water disinfectants.

This commentary, by South African scientists Thembela Hillie and Mbhuti Hlophe, examines nanoscience's potential to solve the technical challenges associated with removing pollutants from water. The authors describe a range of nano-based water treatment technologies already in the marketplace and discuss how nanofiltration membranes can be used in low-cost methods to produce safe drinking water. They highlight a case study in South Africa where such membranes were used to treat brackish groundwater.

The authors emphasise the importance of technology transfer in getting nano-based solutions to the countries that need them, arguing that direct transfer does not often work. Rather, what developing countries need are approaches that combine technology transfer with technology adaptation and adoption — involving local stakeholders in establishing water treatment devices and developing local capacity to use them.

This paper by scientists at the University of Hyderabad examines the nanoscience debate in India. Nanoscience's revolutionary potential and economic benefits are assessed against ethical, legal, social and environmental (ELSE) issues.

The authors present commercial applications, investment, risks and regulatory mechanisms, using the case of Bt cotton in India to show the implications of a new technology. They argue that India's diverse socio-cultural landscape means that nanoscience is likely to have uneven and multilayered effects.

India's scientists do not advocate regulation at the current stage of research — so as not to slow down development, say the authors. But they add that a broad-based and transparent regulatory body to address ELSE issues and funding for research on them would be beneficial.

This report, published by the Project on Emerging Technologies at the Woodrow Wilson International Center for Scholars, looks at social and ethical issues of emerging technologies, with a focus on nanotechnologies.

The author examines social context issues such as unequal access to health care, morally controversial practices such as synthetic biology, the emergence of technoculture, and life issues.

He discusses three common misconceptions; that it is too soon to understand the ethical implications of new technologies; that raising ethical issues hinders technological and social progress; and that the sole purpose of ethical and social research is to secure public acceptance.

The author concludes that ethical considerations can anticipate and proactively address any negative aspects.

In 2003, the UK Government commissioned the UK Royal Society, and the UK Royal Academy of Engineering, to conduct an enquiry into the potential risks and benefits of nanotechnology. For this, they collected evidence from various parties, including the science and technology officer of the British Consulate in Brazil, Alexandra Ozorio de Almeida.

In her questionnaire answers, Ozorio de Almeida described the Brazilian research institutes and developments in nanotechnology. She estimated that the development of nanotechnology will receive some 77.7 million reais (US$30 million) from the government between 2004 and 2007.

Ozorio de Almeida gave details of federally funded nanotechnology research networks, funding agency efforts, the location of research teams, and regulatory frameworks. At the time of the evidence, there were no regulations on research and development in nanotechnology, but a bill was underway. In addition, public interest and knowledge about the field was not very strong or accurate, wrote Ozorio de Almeida.

In June 2004, the Meridian Institute held a meeting of nanotechnology science policy advisors from 25 countries and the European Union. Argentina, Brazil, India, Mexico and South Africa were all represented.

In preparation for the meeting, participants were asked to answer a questionnaire. In it, they described national research and development programmes, funding and regulations for nanotechnology. They were also asked to say what they believed were the key issues that needed to be addressed in order to ensure the responsible development of nanotechnology.

The Meridian Institute's website provides access to the completed questionnaires, including answers and presentations from the developing nations mentioned above. These documents offer valuable insight into the growing industries of the most important nanotechnology players in the developing world.

The final report of the June meeting, also available on this site, includes a chapter summarising the discussions that took place in a workgroup on nanotechnologies in developing countries.

This report, published by the Meridian Institute describes the growing interest that developing countries, including Brazil, China, India and South Africa are showing for nanotechnology. It describes the ways in which nanotechnology applications could solve problems of health, sanitation, and pollution and provide faster, cheaper information and communication technologies.

The report also reviews the challenges of using nanotechnology for and in developing nations. Finally, it outlines the roles and responsibilities of different stakeholders in ensuring that nanotechnology moves forward responsibly.

The Meridian Institute says nanotechnology could play a role in achieving the UN Millennium Development Goals — a set of quantified development objectives to be achieved by 2015. As a result, governments of rich nations should dedicate a "reasonable" portion of their overseas development assistance to nanotechnology.

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This briefing paper from the US Pacific Research Institute explores three potential regulatory frameworks for nanotechnology: prohibiting it, limiting it to military applications, and regulating research into civilian applications.

It says an outright ban is unworkable and restricting its use to military applications would deny humanity of many of its potential benefits.

The paper therefore concludes that a combination of modest regulation, research into applications that are of interest to civilians, and the promotion of self-regulation, is they best way to harness nanotechnology's benefits whilst minimising risk. It examines the benefits and applications of such a system in the context of research, use and export, and of professional ethics and inherent safety.

This report analyses the technological trend for decreasing size, focussing specifically on nanotechnology and its implications. Produced by the ETC Group, a Canadian non-governmental organisation and critic of nanotechnology, it provides an overview of nanotechnology, its impacts and risks.

With plentiful background material, the report describes in detail the range of present and future 'atomtechnologies', how they work, and some of the new products we might expect to see in the near future. It identifies the major players in the field, including governments, universities and companies small and large, and goes on to make policy recommendations.

The report urges caution regarding the adoption of nanotechnology and warns of its potential negative impacts. Highlighting the lack of intergovernmental forums focussing on nanotechnology, it calls for governments and civil society organisations to form an 'international convention for the evaluation of new technologies'. The report also contains a useful glossary.

This paper by Anisa Mnyusiwall and colleagues at the University of Toronto, Canada reviews the state of nanotechnology literature, funding and policy documents.

Writing in the journal Nanotechnology, the authors say that although nanotechnology promises great developments for medicine, electronics and materials and has abundant funding, quality research on its ethical, legal and social implications is lacking. This is not because of a lack of funds, they say, but rather a need for quality proposals.

Summarising the key concerns about nanotechnology, they warn that unless the 'ethics gap' is closed, nanotechnology itself is under threat: public fear may prompt its rejection before its potential has been fully assessed. The authors call for funding to be set aside to address this, and for large-scale interdisciplinary research on ethical issues, capacity building, public engagement, and the involvement of developing countries.