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

Area of Science:

• Ophthalmology
• Optometry
• Materials Science

Background:

• Ultraviolet radiation (UVR) poses a significant risk to ocular health, contributing to various eye diseases.
• The UV-blocking capabilities of daily disposable contact lenses are not fully understood, necessitating further investigation.

Purpose of the Study:

• To evaluate the spectral transmittance of commercially available daily disposable contact lenses across UV-B, UV-A, and visible light spectra.
• To identify factors influencing the UV-blocking efficacy of these contact lenses.

Main Methods:

• Spectrophotometric analysis of thirteen different daily disposable contact lens brands.
• Documentation of lens properties including oxygen permeability, water content, thickness, and FDA material classification.
• Statistical analysis using a generalized linear mixed model (GLMM) to determine predictors of spectral transmittance.

Main Results:

• All lenses exhibited high visible light transmittance (>88%).
• Significant variation in UV attenuation was observed, with some lenses blocking most UVR and others transmitting over 70%.
• Lens power was identified as the primary predictor of UV transmittance, with higher minus powers correlating with lower UV protection.

Conclusions:

• Daily disposable contact lenses demonstrate considerable variability in their UV-blocking effectiveness.
• While lens power influences UV protection, material composition and inherent UV transmittance properties are crucial factors for selecting lenses that offer optimal ocular protection against UVR.