PROS AND CONS: Nanotechnology is being used to treat water in laboratory settings, but not yet on a large scale. Picture: THE TIMES
PROS AND CONS: Nanotechnology is being used to treat water in laboratory settings, but not yet on a large scale. Picture: THE TIMES

In 2005, there were 54 registered nanotechnology products in the world. The products contain tiny particles of about a billionth of a metre in size that can be used in water treatment, medicines and even sunscreens.

Last year, there were more than 1,300 such products in the fast-developing scientific niche, and it is expected that there will be between 3,400 and 4,000 by 2020, says Ndeke Musee, head of the Council for Scientific and Industrial Research’s (CSIR’s) Nanotech Environmental Impacts Research Group.

"We know that in 20 years’ time, nanotechnology will be common in products and many applications. Currently, we mostly import nano-products into SA — such as textiles (nanofibres), paints (easy to clean) and cosmetics — which triggers the need for regulations," he says.

However, there is a growing body of evidence that some — but not all — nano-products can be toxic to humans and bad for the environment. Nanotechnology, a fast-developing discipline internationally and in SA, involves managing and manipulating matter on an atomic level, and deals with structures between one and 100 nanometres in size. A nanometre is one billionth of a metre.

Nanotechnology can be found in textiles, pharmaceuticals, water purification and cosmetics, among other industries.

For example, a number of sunscreens contain titanium oxide nanoparticles.

The head of the Nanomaterials Science Research Group at the University of Johannesburg, Bhekie Mamba, who develops nanomaterials to clean water, says: "Producing nanomaterials is still expensive, but there is also hesitancy in the market because what is the fate of them once you’ve used them?

"When nanomaterials are used in computer chips, people don’t question it because they’re using it, not eating it or ingesting it," he says, noting that nanotechnology is now being used in water purification and cosmetics and suntan lotions, as well as for drug delivery. "You load the drug onto a nanomaterial, and it goes to the point where it delivers the therapy," Prof Mamba says.

The question is what happens to the nanomaterial after it has served its purpose? It can enter water treatment facilities, rivers, the air, the soil.

"Technologies all have risks (and) it is about how you manage them," Dr Musee says.

However, in conjunction with developing SA’s nanotechnology industry, South African researchers are assessing the risks of different nanomaterials, and both processes are funded by the Department of Science and Technology, he says.

In the past, SA has been playing catch-up in terms of environmental issues, but in nanotoxicology the country is on an equal footing with the rest of the world, says Victor Wepener, director of the School of Biological Sciences at North West University.

"Nanotechnology is moving from the development (of nanoproducts in laboratories) into a phase where people are going to start producing or wanting to produce large volumes," the professor says.

"The Department of Science and Technology is putting quite a lot of effort into developing frameworks to identify risks. There are research programmes to identify potential risks before the upscaling takes place."

The National Institute for Occupational Health "(conducts) research on all aspects of particle toxicology and pathology", says the institute’s Mary Gulumian, who also heads the national steering committee investigating nanotechnology risk.

"One is able to regulate nanotechnologies once the health and environmental adverse effects of the used nanomaterials are known…. (In the meantime) the international and national regulatory and other bodies have advised that nanotechnology producers should exercise the precautionary principle."

While SA is not yet a large-scale producer of nanomaterials, it is involved in laboratory-based synthesis of nanomaterials. But, as Dr Musee says, South African companies are looking to produce nanomaterials, although he cannot disclose their names.

Prof Wepener says that SA is "fortunate" because there is no large-scale production in the country yet.

"We can address the potential risks … it is better than pesticides, which are out there in the environment and we’re retrospectively trying to control use."

However, the difficulty with nanomaterials is that they are so small and consequently difficult to detect.

"The methodology to detect the nanomaterials in the environment does not exist," Prof Wepener says, adding that this is a problem internationally.

"At the laboratory level, the research is controlled and you can determine how much of the nanomaterial is in a beaker."

Dr Musee uses the example of trying to find nanomaterials in water: "Nanomaterials are difficult to detect, but you can see the effects when toxicity studies are done. The problem is size — it’s not easy to detect with the present range of facilities.

"It’s similar to looking for a needle in a haystack."

Prof Wepener suggests that production-side management is the way to manage risks.

"(Detection difficulty) is why you are not going to get environmental legislation in terms of levels in the environment, but you can legislate the amount that can be released…. It requires regulation at the production phase, rather than retrospectively."

The positive side is that "in the past, SA has been playing catch-up on environmental issues … fortunately, with nanotechnology, we’re involved in the studies as they are happening in Europe and North America."

However, Dr Musee highlights the need to manage the introduction of nanotechnology carefully: "We need evidence-based science to decide on the risk.… (The need for regulation) is not anti-nanotechnology growth," he says.

"You cannot introduce a new industry … without considering its effects on society and the environment…. Irresponsible development may affect the perception of nanotechnology, and other future emerging technologies through the legacy of nanotechnology," he says.