Estimation of Individual Exposure to Erythemal Weighted UVR by Multi-Sensor Measurements and Integral Calculation

Abstract

Ultraviolet radiation (UVR) can be hazardous to humans, especially children, and is associated with sunburn, melanoma, and the risk of skin cancer. Understanding and estimating adults’ and children’s UVR exposure is critical to the design of effective interventions and the production of healthy UVR environments. Currently, there are limitations to the ways computer modeling and field measurements estimate individual UVR exposure in a given landscape. To address these limitations, this study developed an approach of integral calculation using six-directional (up, down, south, north, east, and west) field-measured UVR data and the estimated body exposure ratios (ER) for both children and adults. This approach showed high agreement when compared to a validated approach using ambient UVR and estimated ER data with a high r-square value (90.72% for child and adult models), and a low mean squared error (6.0% for child model and 5.1% for adult model) in an open area. This approach acting as a complementary tool between the climatology level and individual level can be used to estimate individual UVR exposure in a landscape with a complicated shady environment. In addition, measuring daily UVR data from six directions under open sky conditions confirmed that personal dosimeters underestimate actual individual UVR exposure.

Satellite-Based Personal UV Dose Estimation

“…Additionally, the abundance of local shading and varying levels of shade seeking behaviour are (respectively) environmental and individual factors that lower doses and can vary substantially, but that our model does not yet account for due to a lack of information [11,34,51,52]. Our model assumes that subjects are fully exposed for the entire duration of their exposure period when, in reality, builders and skiers could find themselves on slopes that are topographically shaded, and builders especially could be occasionally shaded by foliage, structures, or even their colleagues and vehicles.…”

“…On hot days, people will naturally seek such shade more so than on cold days. Additionally, recent research has found that dosimeters are prone to underestimating doses when subject to complex environmental shading such as man-made canopies [52]. By not accounting for any level of environmental shading or individual shade-seeking behaviour, our approach can overestimate doses, but it is not clear if this over-estimation is significant here as the original study for the builders data specifically chose locations with a lack of shade to avoid these issues [39] and most ski slopes are not shaded.…”

Bringing Light into Darkness—Comparison of Different Personal Dosimeters for Assessment of Solar Ultraviolet Exposure

“…This work is also intended to serve this purpose. A classification is therefore difficult and can only be compared with modelling [47][48][49].…”

Estimating personal solar ultraviolet radiation exposure through time spent outdoors, ambient levels and modelling approaches*

“…We found that modelled personal UVR exposure (based on a combination of self‐reported time spent outdoors and ambient UVR levels) and self‐reported time outdoors were equally good and better predictors of measured personal UVR exposure than ambient UVR. Previous studies 9,11–13 exploring UVR exposure modelling approaches include an algorithm (Genesis‐UV) to retrospectively estimate lifetime occupational exposure, and a 3D numeric model (SimUVex/SimUVex v2) that estimates site‐specific erythemal doses received at an individual level; therefore, it is not possible to compare their findings with ours. However, our observation that self‐reported time outdoors and a modelling approach could better predict measured personal UVR exposure compared with the ambient UVR is in line with our previous simulation study, 6 which showed that ambient UVR alone could explain only 16% of the variability in the annual measured personal UVR exposure whereas self‐reported time spent outdoors along with ambient UVR increased the explained variation to 40%.…”

“…To date, the available evidence evaluating the validity of the aforementioned surrogates of UVR exposure is still limited, with few studies validating UVR exposure modelling approaches 9,11–13 . Moreover, studies comparing validity of different surrogates of long‐term UVR exposure are nonexistent.…”