Science of the small may carry big risks

Beauty products don’t have a fantastic record on health over the centuries - think mercury face powders in Ancient Egypt or lead and arsenic face creams popular in the Elizabethan court. Today there is a widespread expectation that regulators will keep high risk ingredients out of cosmetics. Unfortunately, nanotechnology, the “science of the small” is introducing a new generation of high risk cosmetic ingredients whose health effects remain poorly understood and effectively unregulated.

The beauty industry is one of the most enthusiastic early adopters of nanotechnology. L’Oreal, sponsor of the recent L’Oreal Melbourne Fashion Festival and the world’s largest cosmetics company, is also the top nanotechnology patent holder in the United States. Other big name brands like Revlon, Avon, Prestige, The Body Shop, Dr Brandt, Sircuit, Zelens and dozens of boutique lines also sell nano-cosmetics.

When most people think of nanotechnology - if they think of nanotechnology at all - common images are futuristic tiny robots, performing advanced surgery or being deployed on the battle ground. But at a more prosaic level, the beauty industry is adding “nanoparticles” to lipstick, foundation and anti-ageing products because at this extremely small scale familiar substances have novel optical and biological properties.

As larger particles titanium dioxide and zinc oxide are white and opaque - as in the old fashioned zinc sunscreen worn by surf life savers. But at the nanoscale, a hundred times smaller than a red blood cell, these same substances become transparent. This enables their use in moisturisers and foundations. Other nanoparticles such as aluminium oxide give a “soft focus” effect that disguises wrinkles. These are used in high-end concealer sticks, foundations and face powders. Carbon “fullerene” nanoparticles are used in anti-ageing creams and moisturisers partly because these tiny nanoparticles penetrate skin so effectively.

The beauty industry’s willingness to use novel nanoparticles in its products while their health effects remain so poorly understood has raised a few eyebrows among the less fashion-conscious scientific community. The increased capacity of nanoparticles to penetrate skin and gain access to our bodies’ cells is a double edged sword: it may be useful for medical purposes, but it could also result in far greater uptake of substances that have a negative health effect.

Recent research shows that nanoparticles of titanium dioxide, one of the most commonly used cosmetic ingredients, can move across the placenta of pregnant mice, resulting in brain damage and reduced sperm production in male offspring. An earlier mice study shows that carbon fullerenes also move across the placenta and damage developing embryos.

Test tube studies have shown that nanoparticles commonly used in cosmetics and sunscreens can damage DNA and cause serious cellular damage.

Outside the lab, Blue Scope Steel has found that where workers wearing nano-sunscreens have left handprints on Colour Bond roofs, those sections of roof aged 100 times more rapidly than surrounding areas. What these findings mean for women of child-bearing age who wear nano-cosmetics daily, the millions of Australians who wear nano-sunscreens regularly, or the workers who manufacture nano beauty products, remains uncertain.

The cosmetics industry argues that risks for consumers are low, as there is no evidence that nanoparticles in cosmetics penetrate healthy, intact adult skin. The latter point is true for most nanoparticles, although it’s also true that there is still little published skin penetration research; CSIRO and others are engaged in ongoing studies. However, it is important to recognise that many nanoparticles are used in moisturisers and anti-ageing creams which contain penetration enhancers specifically designed to increase skin uptake of product ingredients. We also know that particles are much more likely to penetrate damaged skin, for example in the presence of pimples, eczema or sunburn.

Nano-cosmetics have so far escaped public scrutiny and debate. Unfortunately, they have also fallen through loopholes in government regulation. In 2004 the world’s oldest scientific institution, the United Kingdom’s Royal Society, recommended that given their risks, all products containing nano-ingredients should pass rigorous safety testing, and face mandatory labelling, before they can be sold. Global reinsurance agent Swiss Re recommended that “the precautionary principle should be applied whatever the difficulties”. But although potentially hundreds of products are on sale in Australia right now, not a single nano-cosmetic has gone through safety assessment by regulators and companies are still not required to label nano-ingredients.

The emerging nanotechnology industry receives a great deal of government support and public funding, in Victoria and elsewhere. Given that the public faces very intimate daily exposure to nano-cosmetics and personal care products it doesn’t seem unreasonable to demand rigour in their safety assessment and mandatory labelling to enable informed purchasing choices.

As fashion fans tally up the highs and lows of L’Oreal Melbourne Fashion Week, it’s a good time to reflect on the lessons learnt from past beauty product disasters and to ensure that we avoid their repeat.