Melanin provides protection against excess exposure to solar ultraviolet radiation (UVR) and related adverse health effects. Diffuse Reflectance Spectroscopy (DRS) can be used to calculate 2 cutaneous melanin and erythema, but this is complex and has been mostly used for light-tomedium pigmented skin. Handheld reflectance spectrophotometers, such as the Mexameter® MX18, can also be used. We compared DRS-calculated melanin and erythema values with Mexameter melanin and erythema index values to understand how these techniques / measurements correlate in an African population of predominantly deeply-pigmented skin. 503 participants comprised 68.5% self-identified Black African, 9.9% Indian/Asian, 18.4% White and 2.9% Coloured. The majority of Black African (45%), Indian/Asian (34%) and Coloured This finding is considered spurious and may result from the complexity of separating brown and red pigment when using narrowband reflectance techniques. Further work is needed to understand melanin, erythema and colour in Black skin given sun-related health risks in vulnerable groups in Africa.

Temperatures in Africa are expected to increase by the end of the century. Heat-related health impacts and perceived health symptoms are potentially a problem, especially in public schools with limited resources. Students (n = 252) aged ~14–18 years from eight high schools completed an hourly heat-health symptom log over 5 days. Data loggers measured indoor classroom temperatures. A high proportion of students felt tired (97.2%), had low concentration (96.8%) and felt sleepy (94.1%) during at least one hour on any day. There were statistically significant correlations, when controlling for school cluster effect and time of day, between indoor temperatures ≥32 °C and students who felt tired and found it hard to breathe. Consistently higher indoor classroom temperatures were observed in classrooms constructed of prefabricated asbestos sheeting with corrugated iron roof and converted shipping container compared to brick classrooms. Longitudinal studies in multiple seasons and different classroom building types are needed.

South African schoolchildren at urban government schools do have some knowledge about sun protection, and they do have some positive sun behaviours; however, the reported occurrence of sunburn, a risk factor for skin cancer, was relatively high. There were few differences in responses by sex and some differences by skin type. These findings are important for the development of appropriate sun protection programmes aimed at schoolchildren in South Africa and other countries with similar multi-ethnic populations.

The elevated prevalence of some respiratory health outcomes among schoolchildren, especially in conjunction with domestic fossil fuel burning, is of concern. The data collected in this study may be used to complement or form a basis for future policy regarding indoor or ambient air quality in the area.