Lois Rogers

The Sunday Times 09 November 2014

DIRTY air in the city may not make you feel so pretty. Scientific research suggests that pollution could age the appearance of women’s skin 10% faster than those who live in the countryside.

A study of 200 women aged 30 to 45 in China compared those who lived in a city such as Beijing with others who lived in rural areas. While both suffered sun damage, the city dwellers aged the most. This is because a cocktail of 224 pollutants found in city air all over the world destroy proteins called keratins that protect the skin from moisture loss.

The Chinese research was funded by Procter & Gamble, which makes Olay skincare products. Scientists now recognise that pollution particles much smaller than a grain of sand can penetrate the skin and break up cells. This study confirmed that free radicals formed in the body by exposure to heavy metals and other pollutants from diesel engines broke down keratins and thinned the skin barrier. 

Both groups of women had similar lifestyles and were exposed to comparable amounts of ultraviolet (UV) radiation. But while those from the country showed higher rates of sunlight-related ageing, overall damage was worse among those living in the inner city.

The research was carried out by Wei Liu, a professor of dermatology at the China Air Force general hospital in Beijing.

It follows a study of 400 women at the Heinrich Heine University in Düsseldorf, funded by the Estée Lauder cosmetics company, that showed women in urban areas suffered 20% higher rates of hyperpigmentation, or age spots, than those living in rural environments.

Pollution causes inflammation, disrupts the skin’s barrier, damages the collagen that maintains skin elasticity and accelerates wrinkling and ageing.

It was previously believed exposure to UV light was the main cause of varying rates of facial ageing. Now it is believed that up to 50% of the damage is a result of urban pollution.

P&G is looking for ways to control the process by blocking the penetration of polluting chemicals.

Elizabeth Hunt, 46, a teacher and mother of three, said the country air of rural Kent is her prescription for an appearance that belies her age. “My husband and I grow our own vegetables and try not to use supermarkets. Fresh air and long country walks help, too, but city life was never for me.”

Stephanie Williams, a Harley Street dermatologist, has one patient who is a 37-year-old childless, non-smoking Londoner with a high-powered creative job.

“This woman has a lot of stress but she cycles everywhere… and doesn’t take public transport or a cab,” she said.

“Cleansing her face, the white gauze cloth turns completely grey. You can see all the pollution, the chemicals and dirt of the city are on her skin. She’s slim and fit, but her skin age is about 10 years older than her chronological age. It’s a tricky one — you live in the city and you want to be healthy, but you’re more exposed to pollution.”

World Health Organisation data published this year shows that although Britain does not reach the level of pollution experienced in China, nine UK cities consistently breach safe limits for numerous airborne toxins.

A study earlier this year suggested that air quality in Oxford Street, central London, was routinely the worst in the world for levels of nitrogen dioxide, a by-product of diesel. The gas reacts with UV light to produce ozone which in high volumes disrupts skin cell function.

Frauke Neuser, scientific spokesman for P&G, said: “In the past we believed toxic particles in urban dust… are too large to penetrate skin. We now know particles as small as 0.1 of a micrometer, many times smaller than a grain of sand, carry a variety of these toxins and which can penetrate the skin even if the particles themselves can’t.”

P&G is setting up collaborative projects with environmental scientists. One, Irfan Rahman, professor of environmental medicine at Rochester University in New York state, said there is no question pollution worsens the skin damage caused by UV light.

“It is a particular problem in people susceptible to rashes and eczema, or those who have sensitive skin,” he said.

P&G’s rival L’Oréal has bought a Chinese company that produces stick-on facial masks favoured by Asian women to protect their skin against the toxins in urban air. The market for such masks is now worth £130m a year.

Mark Birch-Machin, professor of molecular dermatology at Newcastle University, said there is no dispute that air pollution can damage skin, but added: “There are no concrete figures as to how much of a problem this is.”