Sunscreens sold on supermarket shelves in SA are reliable and provide adequate protection against sun damage, says a top expert.
Dr Beverley Summers, a lecturer in the pharmacy department of the University of Limpopo, was commenting on the sunscreen saga that unfolded this week when it emerged the Cancer Association of SA (Cansa) had tested several local products, finding they were not optimal in protecting against sun damage.
Investigative magazine Noseweek reported on the confidentiality agreement that forbade Cansa from making its test results public.
Summers’s photobiology laboratory at the Medunsa campus tests many of the sun creams on store shelves in SA.
She said Cansa was “trying to do the right thing” in testing them, but this had “backfired” on the cancer watchdog and on sunscreen makers.
Misinformation was being spread in a “frenzy triggered by a lack of understanding”.
“Cansa subjected the samples to a test, which in all fairness the older products weren’t designed to meet.”
Summers said the sun lotions had failed the Colipa test, the basis for a new ISO international standard for UVA assessment of sunscreens that was only finalised in May. It gauges whether sunscreens break down chemically when exposed to harmful UVA rays.
“The old tests just tested the UVA and UVB spectrum, the new ones test the spectrum and then irradiate the sunscreen with a huge UV dose equivalent to the SPF of the sunscreen.
“Some sunscreens, we know, do break down a little bit, but not so much that they become useless when irradiated. This new one [test] just takes the spectrum of protection and level of protection, irradiates it, and then takes the level again at the end.
“The new test tests for how much UVA protection sunscreen loses when irradiated. The tests show we lose a little bit on the sunscreens that didn’t make the grade. If you reapply your sunscreen regularly, it would only have a minor effect.”
This was “unless you spend hours and hours in the sun without reapplying your sunscreens”.
“I think South African sunscreens generally are reliable, certainly the newer formulations are. It’s possible that some of the older formulations need to be updated and they certainly will be after this. The sunscreens that don’t photodegrade and lose their stability are the ones containing zinc oxide and titanium dioxide.”
Summers explained that most baby care products and children’s suncare products contained these chemicals.
“They are less reactive to the skin and less likely to biodegrade.”
Cansa said that from next week, it would provide a list on its website indicating the names of all sunscreens adhering to the EU standards.
Summers added that the Cansa Seal of Recognition was “still valid” and “still a pretty good label”. “The manufacturers would reformulate anyway, this has just speeded up the process, but it does not mean the older products are useless and should not be used.”
A dermatologist in the south of Joburg said there was “a loss of confidence” in sunscreens, which was a pity, as several local sunscreens offered excellent protection.
“But even with a high SPF sunscreen, always encourage patients that you can’t solely rely on sunscreen. Avoid sun between 10am and 3pm as much as possible and wear protective clothing. We do recommend reapplication every two or three hours,” he said.