Experts say new data showing New Zealand’s air quality is ranked as one of the world’s highest will contribute to an elevated risk of skin cancer for thousands of skiers this season.
According to latest air quality data from Yale and Columbia Universities, New Zealand has the world’s seventh cleanest air when compared with 180 countries; however dermatologists say the lack of pollution significantly increases exposure to UV – particularly at altitude.
New Zealand also has the world’s highest rates of melanoma with 4,000 Kiwis diagnosed and over 350 dying from this form of cancer every year.
Around 318,000 New Zealanders ski or snowboard each year and local ski fields are set to open for the 2022 season within the coming days.
Dr Niyati Sharma, MoleMap dermatologist, says research shows UV exposure on a New Zealand ski field is up to 30 per cent higher than at sea level.
She says most skiers are unaware of the level of elevated risk they face for every hour spent on the mountain.
“What we know about leisure activities at altitude is that there is decreased atmospheric shielding from UV radiation, which leads to significantly more UV exposure than at sea level.
“For every 1000m increase in altitude the UV radiation level will increase about 10 per cent. New Zealand’s highest ski field is over 2300m and the peak exposure levels could be three times higher than at sea level.
“This means the level of UV exposure while skiing in the winter is equivalent to playing a round of golf in the summer.
“Unfortunately for many of us, winter is synonymous with less sun which tends to lead to a high level of complacency among regular skiers.
“The reality is that UV exposure levels are much more damaging at altitude than most skiers would realise,” she says.
Dr Sharma says research shows the surface of snow acts as a mirror reflecting up to 80 per cent of the sun’s rays back at us – intensifying the levels of UV absorbed through the skin.
“We know that spending time around reflective surfaces like snow and ice means you are getting up to 200 per cent more harmful UV exposure than at the beach.
“This can result in permanent damage to areas of the upper torso not commonly exposed to UV – such as the underside of the chin.
“Research has found that those who work on ski fields and spend long periods of time at altitude have higher rates of actinic keratosis, a precancerous lesion found on sun-damaged skin, than the general population – which tends to highlight the risk, skiers may face,” she says.
Dr Sharma says it is important to mitigate the exposure to UV by protecting your skin and eyes.
“There are a range of ways skiers can protect themselves this winter: the most fundamental of which includes using a good quality sunscreen with maximum SPF you can buy plus a SPF lip balm and UV protective eye gear.
“Even while skiing, sweat will reduce the effectiveness of sunscreen and so it is important to reapply it every two hours, even if you have a water resistant one.
“To help prevent ocular melanoma and cataracts, it is also recommended that skiers use wraparound goggles that are labelled as UV protective – rather than sunglasses which can let reflective UV in and also make sure they cover their neck with clothing that is UV rated,” she says.
Dr Sharma says the earth’s elliptical orbit means country’s are exposed to more sunlight than Northern Hemisphere counterparts.
“We know that New Zealanders are already seeing around 13 per cent more UV exposure than the countries above the equator on the equivalent latitude – along with the clean air and our outdoor lifestyles it is one of the reasons we have the world’s highest prevalence of skin cancer.
“It is essential that Kiwis, particularly those with common risk factors such as fair skin, red or blond hair or a history of sun damage get screened regularly to prevent the development of melanoma.
“This can be done by your GP or through a skin cancer surveillance service such as MoleMap,” she says.