Elle's sunscreen maker in hot water

The maker of Elle Macpherson and Jerry Hall's favourite sunscreen is in hot water with Australia's drugs regulator over claims made on its website.

The zinc-based sunscreen promoted by the world-famous models has been taken to task for suggesting some rival products are dangerous for sunlovers to use.

The Therapeutic Goods Administration (TGA) has ordered Invisible Zinc's manufacturer to dump references to the sunscreen being "nano free" from its website.

The sunscreen is promoted as being free from the nanoparticles zinc oxide and titanium dioxide, which some scientific studies claim can pose health risks.

However, other studies have played down the supposed risks.

The TGA argues that promotions of Invisible Zinc as "not nano" and "nano free" could imply that sunscreens containing nanoparticles are unsafe.

"Although labelling of therapeutic goods including sunscreens as `nanoparticle free' is permitted, TGA remains concerned that promotion of goods as `nano free' may imply that therapeutic goods that contain nanoparticles are unsafe when there is no evidence that this is the case," a TGA spokeswoman said.

"The TGA carefully considered this matter under the advertising provisions in the Therapeutic Goods Act and has ordered the company to undertake a number of remedial actions.

"These include withdrawal of the advertisement and any representations that other sunscreens may be harmful or ineffectual or contain ingredients that may be harmful or ineffectual (including `nan' ingredients or chemical ingredients."

The sunscreen's US-based manufacturer Valeant, which bought Invisible Zinc from its Australian founder Ganehill Pty Ltd in April, can appeal the TGA's order.

Despite the ruling being made public on Wednesday, the Invisible Zinc website still had references to "not nano" and "nano free".

Under the heading Micronised (Not Nano) Sunscreens, the website explains that Invisible Zinc uses zinc oxide particles which are up to 50 times larger than the size of typical nanoparticles in some other sunscreens.

Nanoparticles are smaller than 100 billionths of a metre.

Several sunscreens contain nano-grade titanium dioxide and zinc oxide, which offer sun protection and leave little residue when spread on skin.

The TGA previously carried out two reviews and concluded there was evidence zinc oxide and titanium could damage cells though it was questionable whether nanoparticles could penetrate the body's outer "dead" layer of skin.

The CSIRO is currently carrying out more studies, which it hopes will be complete by the end of 2011.

The head of CSIRO's division of material science and engineering Cathy Foley, who oversees the body's nano safety research program, said the research so far had not raised any alarm bells about nanoparticles in sunscreen.

"So far none of the data we have got tells us there are any concerns at this stage, but the work is continuing," she told AAP.

"Until the science is there it's not good science to jump the gun and say we are worried about it and we should ban everything."

But environment group Friends of the Earth believes that until studies confirm the safety of nanoparticles in sunscreens, people with skin conditions such as eczema and psoriasis and young children should not use them.

Spokeswoman Elena McMaster also criticised the TGA, saying its ruling was an "attack on nano-labelling".

"It sets a dangerous precedent, and other manufacturers may be scared away from labelling their products as nano free," she said.

"It means consumers will be left in the dark about whether there are nanoparticles in their sunscreens or not."

Calls to Valeant's Sydney office were not returned.