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[Michaelangelica]

No such thing as a safe sunscreen?

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Do nanoparticles in sunscreens and cosmetics penetrate the skin?
Do nanoparticles in sunscreens and cosmetics penetrate the skin? | nano.foe.org.au

"There are sunscreens out there being sold right now that contain nano ingredients that could be causing quite serious toxicity problems," Georgia Miller, from Friends of the Earth (FOTE), said.

Associate Professor Tom Faunce, from the Australian National University (ANU), says concerns centre on nanotechnology's unknowns.

"The big issue is to what extent do they [nano particles] get inside the cells through the dead skin on the outer surface of the body?" he said.

"To what extent do they accumulate? To what extent do they actually cause long-term injury?

"We really don't have this information."

Many sunscreens contain titanium dioxide and zinc oxide - effective reflectors of the sun's rays - but they leave an inconvenient thick, sticky, white layer on the skin.

Making these ingredients nano-sized - the particles used in sunscreen are about 200 times smaller than human blood cells -mean they rub on clear.

"A nanometre is a billionth of a metre," Dr Faunce said.

"We're talking about particles that are about 40 nanometres - very small, but they actually have a larger surface area at that size.

"So they still have the capacity - in fact an enhanced capacity in some cases - to reflect ultraviolet rays."

This all might sound attractive, but according to Dr Faunce there are concerns about what happens if these nano particles were to enter the body.

Unable to convince the Government to remove the products from shelves, FOTE is taking on manufacturers and alerting consumers of what they say are the potential dangers of particular sunscreens.

Nano-tech sunscreen presents potential health risk - ABC News (Australian Broadcasting Corporation)

Brief background information on nanoparticles in sunscreens | nano.foe.org.au

Early studies on the safety of zinc oxide nanoparticles used in sunscreens are reassuring, say scientists.

But the studies still can't tell us the actual risk of using products containing these tiny particles.

Two of the first Australian studies on the safety of zinc oxide nanoparticles will be presented later this month at the International Conference on Nanoscience and Nanotechnology in Melbourne.

One study looked at what happens when sunscreen containing these nanoparticles is applied to human skin.

"You put these materials on your skin and they disappear," says researcher Professor Brian Gulson from Macquarie University's Graduate School of the Environment in Sydney.

"Surely they must go somewhere. Are they being absorbed through the skin?"

Tests on sunscreen nanoparticles 'reassuring' (ABC News in Science)