Spectral Transmittance of Daily Disposable Contact Lenses: Variability in Ultraviolet Blocking

Ultraviolet radiation (UVR) is a well-established risk factor for ocular diseases; however, the ultraviolet-blocking properties of daily disposable contact lenses remain insufficiently characterized. This study evaluated thirteen commercially available lenses to determine their spectral transmittance across UV-B, UV-A, and visible light ranges using a UV-visible spectrophotometer. The oxygen permeability, central thickness, water content, and FDA material classification of each lens were documented, and oxygen transmissibility was subsequently calculated. A generalized linear mixed model (GLMM) was applied to identify predictors of spectral transmittance. All lenses demonstrated high visible light transmittance (>88%), but exhibited substantial variation in UV attenuation. While several lenses effectively blocked most UV radiation, others transmitted more than 70%. The analysis revealed that lens power was the most consistent predictor of spectral transmittance, with higher minus powers associated with reduced UV-blocking efficacy. Moisture content and material classification also influenced UV protection but had minimal effect on visible light transmission. In conclusion, daily disposable contact lenses vary considerably in their UV-blocking capabilities, and although lens power cannot be altered, consideration of material composition and UV transmittance properties may assist in selecting lenses that provide optimal ocular protection.