School children don't apply enough sunscreen: research

16 February, 2012

Queensland children may not be applying enough sunscreen to protect them from sunburn and skin cancer, a Queensland University of Technology sun safety researcher has found.

Postgraduate researcher Abbey Diaz, from QUT's AusSun Research Laboratory, investigated how much SPF 30+ sunscreen 87 primary school-aged children in Queensland applied. She also studied whether using a pump, squeeze bottle or roll-on applicator made any difference to the thickness of the sunscreen they put on.

"The SPF (sun protection factor) of sunscreen depends on the thickness of application so if it is applied too thinly the skin will have substantially lower SPF than one might expect," Ms Diaz said.

"We found the children were applying on average only a quarter of the amount of sunscreen applied by sunscreen manufacturers to test the SPF which is 2mg per square cm of skin. Based on what we know from other research, we can say that it is unlikely that this is enough sunscreen to protect children from sunburn and other sun damage.

"This is concerning because sun exposure during childhood has been found to be an important risk factor for future skin cancer. Children typically spend substantial time in the sun during times when the UV index is high, such as during big lunch at school.

"Early sun-exposure contributes to accumulated life-time exposure, increasing a child's chance of developing skin cancer in later life.

"In fact, it has been estimated that regular sunscreen use during childhood and adolescence can reduce lifetime skin cancer risk by up to 80 per cent."

Ms Diaz conducted her study over three weeks. Children, aged five to 12, applied their sunscreen on school-day mornings, without physical assistance from their parents.

Each week the children used a different sunscreen dispenser: either a pump, squeeze or roll-on.

The order the children used these dispensers depended on the study group to which that they had been allocated.

"This was done so we could ensure any difference in application thickness observed between dispenser types was not simply a time effect," Ms Diaz said.

"The team weighed the dispensers each week to determine how much had been used, and divided this by the area of the skin that sunscreen had been applied to. Children applied the most sunscreen from a pump bottle (0.75 mg/cm2), and 0.57 mg/cm2 when using a squeeze bottle but only 0.22 mg/cm2 with a roll-on dispenser.

"These results suggest that the roll-on may not provide an adequate coverage of sunscreen for children. Other dispenser types, such as pump and squeeze bottles, appear to be more effective for children to use.

"We believe that the more effective dispensers should be available in every household and every school classroom."

Ms Diaz said parents unsure of how much to apply should use the Australia Cancer Council's recommendation of one teaspoon of sunscreen for each limb, the back, and the torso and a half teaspoon for the face and neck for themselves and a proportion of this amount, depending on their size, for their children.

Parents can use the Cancer Council's SunSmart sunscreen calculator: to work how much sunscreen needs to be applied.

"Parents are role models in sunscreen use so the best way to ensure your child applies the right amount of sunscreen is to let them see you applying it as part of your own morning routine, and applying it generously to all skin that is not otherwise covered by clothing, at least 20 minutes before going out in the sun," she said.

"It's best to roughly rub in your sunscreen, not be too vigorous. Let the sunscreen absorb over those 20 minutes, and if you are staying out in the sun, re-apply every two hours," Ms Diaz said.

"Ideally children should apply sunscreen before going to school, before outdoor play or sports times, and again before heading home. To stress something we probably all already know: sunscreen is best used in conjunction with the other sun-protection methods, such as wearing a broad-brim hat, sun-safe clothing, sunglasses and staying in the shade."

Source: Queensland University of Technology