Abstract
Background
Skin cancer is the most common cancer in New Zealand/Aotearoa and the incidence of melanoma, the most serious form of skin cancer, is amongst the highest in the world. Overexposure to ultraviolet radiation (UVR) causes over 90% of all skin cancers. It is also implicated in eye health issues, such as cataract and pterygium. Teenagers have been identified as an at-risk group for sun exposure because they experience higher levels of sunburn and have lower uptake of sun protection measures compared with other age groups. Secondary school sports participation has many associated benefits, but some outdoor summer sport settings have a high UVR exposure profile. There is little evidence that sun protection policies and guidelines are currently embedded at secondary school level or are adopted by summer sports organisations. Sun protection usually remains the responsibility of the competitor. This thesis relates to the secondary school sport of competitive rowing. It considers both the UVR environment within which secondary school rowers compete and the current use of visible sun protection by participants during competition.
Methods
The empirical contribution in this thesis is organised into two parts. The first measures personal UVR exposure using dosimeters positioned on the shoulder of rowers at six regattas held during the 2018-19 and 2019-20 Austral summer seasons. Second, a database of photographs of rowing crews at the race start line afforded comprehensive insights into the use of visible sun protective headwear, sunglasses and clothing by competitors.
Results
Dosimeter measurements included standard erythemal dose (where 1 SED equals 100 joules per m2), SED per hour and percentage ambient UVR. Over two-thirds (67.2%) of individual race-times, which is defined as the total time on the water in order to compete in a rowing race recorded a SED in excess of the Australian Radiation Protection and Nuclear Safety Agency recommendation of 1 SED per day. In addition, 24.1% of race-times equalled or exceeded 1.5 SED, which is the UVR dose estimated to cause just perceivable sunburn in individuals with light coloured skin. The median SED per hour for the five rowing regattas held at Lake Ruataniwha ranged from 0.97-2.37 SED per hour and the median percentage ambient ranged from 17–35%.
The photographic analysis indicated an established culture of cap wearing amongst rowers. In addition, approximately one-third of competitors wore sunglasses. However, one-fifth of competitors wore no headwear or eye protection and younger age groups were observed using the least visible sun protection. Females demonstrated a propensity to wear visors that offer even less sun protection than caps during competition. The use of protective clothing under the rowing zootie was almost non-existent. However, coxswains were well protected with headwear, sunglasses and clothing.
Conclusions
Applying these findings to the Ottawa Charter conceptual framework for health promotion highlights the need for a multifaceted approach if improvements in the use of sun protection by secondary school rowing students is to be achieved. The documented UVR exposure and concurrent information about visible sun protection use provides the opportunity for targeted sun protection strategies to be implemented in the sport of rowing. Targeting the most junior rowers with interventions to improve use of headwear and sunglasses would be a suitable starting point, but leadership from the national rowing body will be required to lift the 20% of rowers who currently do not use any form of headwear or sunglasses to routine adoption of sun protection for racing. Implementing best practice guidelines, including phasing out the use of visors and encouraging the use of sleeved tops to the start line, will improve not only the short- term health of secondary student rowers but should also reduce the long-term risks from overexposure to UVR. The recommendations arising from this research do not extend to the use of sunscreen. Best practice guidelines would, however, need to cover all five sun protection measures which, in addition to the ones studied here, include sunscreen use when competing and use of shade between races. Rowing is a unique and rewarding sport and secondary students should be able to receive the benefits associated with participation without the harms associated with overexposure to the Sun.
Like most summer outdoor sports in Aotearoa, Rowing New Zealand does not currently have a sun protection policy. The development of such a policy that aims to establish habitual sun protection practices on the part of all participants appears to be a necessary response to the personal UVR exposure doses reported in this thesis. Only then will the long-term wellbeing of all secondary school student rowers in relation to overexposure to UVR be realised.