Effectiveness, compliance and application of sunscreen for solar ultraviolet radiation protection in Australia.

Objectives and importance of study: Sunscreens are widely used, not only to prevent acute sunburn, but also for skin cancer prevention and protection against photoaging and other skin conditions related to cumulative solar ultraviolet radiation (UVR) exposure. When correctly applied, sunscreens reduce the amount of UVR reaching the skin and therefore they can reduce harmful effects of such exposures. This paper examines the benefits and risks of sunscreens, compliance requirements and how sunscreen should be used for optimal effectiveness. STUDY TYPE: Narrative review. METHODS: We reviewed evidence relating to the benefits and risks of sunscreens, sunscreen manufacturing compliance, consumer usage of sunscreen and how sunscreen should be used to be most effective. RESULTS: There is strong evidence that sunscreen is safe to use and, when applied correctly, reduces the risk of skin cancer. There is a need to address questions about the impact of sunscreen on vitamin D and its risk to the environment, as well as a need to develop sun protection factor (SPF) sunscreen testing methods that are more reproducible and ethically based. The amount of sunscreen and the way it is applied varies considerably between individuals, and this in turn markedly affects the degree and duration of protection received. Sunscreen should be used in combination with other sun protection measures that include clothing, hats, sunglasses and seeking shade. CONCLUSIONS: Regulation is essential to ensure high-quality, safe and effective sunscreen products are available to the Australian population. There is an important role for governments to put in place skin cancer prevention policies and long-term funding arrangements to build on our successful sunscreen programs so that future generations are afforded the highest level of topical protection against solar UVR.

Burning daylight: balancing vitamin D requirements with sensible sun exposure.

OBJECTIVE: To examine the feasibility of balancing sunlight exposure to meet vitamin D requirements with sun protection guidelines. DESIGN AND SETTING: We used standard erythemal dose and Ultraviolet Index (UVI) data for 1 June 1996 to 30 December 2005 for seven Australian cities to estimate duration of sun exposure required for fair-skinned individuals to synthesise 1000 IU (25 µg) of vitamin D, with 11% and 17% body exposure, for each season and hour of the day. Periods were classified according to whether the UVI was < 3 or ≥ 3 (when sun protection measures are recommended), and whether required duration of exposure was ≤ 30 min, 31-60 min, or > 60 min. MAIN OUTCOME MEASURE: Duration of sunlight exposure required to achieve 1000 IU of vitamin D synthesis. RESULTS: Duration of sunlight exposure required to synthesise 1000 IU of vitamin D varied by time of day, season and city. Although peak UVI periods are typically promoted as between 10 am and 3 pm, UVI was often ≥ 3 before 10 am or after 3 pm. When the UVI was < 3, there were few opportunities to synthesise 1000 IU of vitamin D within 30 min, with either 11% or 17% body exposure. CONCLUSION: There is a delicate line between balancing the beneficial effects of sunlight exposure while avoiding its damaging effects. Physiological and geographical factors may reduce vitamin D synthesis, and supplementation may be necessary to achieve adequate vitamin D status for individuals at risk of deficiency.