UV transmittance in market place sunglasses and their adherence to established standards

Abstract

Background: Sunglasses are used to shade and protect the public’s eyes every day. However some improperly made sunglasses offer inadequate UV protection that shade the eyes and dilate pupils, while letting in a high dose of UV radiation into sensitive ocular tissues. This UV exposure can have acute and chronic effects such as temporary blindness and clouding of the eye. This study investigated the prevalence of sunglasses with poor UV protection and examined any relationships or associations between such sunglasses and their retail price or declared protective standards. Methods: 35 unused sunglasses available in the Metro Vancouver area were tested using an Agilent 8453 UV-visible Spectroscopy System for UV transmittance rates in the UVA, UVB, and UVC wavelengths. Results were statistically analyzed for any potential relationships or associations between price, price categories, total number of wavelengths failed, transmittance test results, decal presence, and types of decals present. Results: Sample sunglasses were distributed to be 51% budget sunglasses, 23% standard sunglasses, and 26% premium sunglasses. Of these 35 sunglasses, 11% failed the 4% permitted transmittance test, and 89% of the sunglasses had some form of UV protection claim adhered or printed on the product. Statistically significant associations, using Chi-squared analysis, could not be found between transmittance test results and price category, UV protection claims, or the type of UV protection claim; p-values were found to be 0.43643, 0.44525, and 0.58402, respectively. A statistically significant relationship, using linear regression, could not be found between price and total wavelengths failed; p-value was found to be 0.2272 with a slope of -0.1334 Conclusion: Though no statistically significant relationships or associations could not be found, the study did find sunglasses that offered inadequate UV protection, leading to the conclusion that there are sunglasses in the Metro Vancouver market that are inappropriate for standard UV protection.