Tiny particles in consumer products pose health and environmental risks and need to be tracked, a group of New Zealand scientists say.

Amid growing worldwide concern about the potential effects of nanoparticles, Kiwi scientists, academics and officials want the government to introduce a labeling system identifying nanomaterials used in products on supermarket shelves and to maintain a public database of nanoproducts.

Finely-ground feed stocks have been around for quite a while, so the commercial use of nano-sized materials is not necessarily new – although thinking about them as such is relatively novel. But manufacturers have stepped up the conscious use of nanomaterials and reportedly they are already used in more than 800 consumer products, including cosmetics, sunblock, clothing, food, washing machines and refrigerators.

A report on the opportunities and drawbacks of nanotechnology has just been published by the Ministry of Research, Science and Technology. It lists more than 70 actions the government should take.

Report editor and University of Canterbury physicist Simon Brown told The Press that apart from nanotechnology’s obvious advantages in the computer and electronics world, there are known and unknown hazards.

Brown conveys a belief that the New Zealand government has yet to face up to nanotechnology.

“My impression is they’re keen to work on the issues, but their departments don’t see it as a priority. Fundamentally, it’s been well-established that some nanoparticles cause negative health impacts. We know that certain nanoparticles cause cancer, damage to genes and can accumulate in your brain if they get into your body,” says Brown. “How should we regulate new products when there is a lack of clarity about the risks? And how do we balance the benefits and risks?”

Silver nanoparticles used in disposable diapers were an example of the possible risks.

“Do they accumulate in sewage ponds, which may stop them breaking down the sludge because they are antibacterial, or if it is then used as fertilizer, is it possible those nanoparticles will accumulate in those plants that grow?” Brown asks.

Another example of unintended consequences had been found in Australia, where sunblock containing nanoparticles used by roofing workers had been shown to cause unpredicted chemical reactions when it fell on to a roof, prematurely corroding the iron.

“It is this potential for the unexpected that makes this difficult to deal with. There’s not just the potential for health and environmental risk, but a business risk too. Labeling gives people a choice and instills a bit of discipline on the system, but it’s not a solution in itself. The worst thing we can do, which is what we’re doing at the moment, is sit around and do nothing,” Brown says.