Comparison of oxidative stress response of in vitro retinal cells exposed to blue light from emissive versus reflective displays

Abstract

During COVID-19, there was increased use of handheld displays in educational settings. There is growing concern that eye health may be affected by prolonged exposure to the light-emitting diodes used as frontlights or backlights in handheld displays. The potential impact of light exposure from tablet-sized devices with different display technologies and various spectral outputs was assessed in an in vitro model using human retinal epithelial (ARPE-19) cells. Cellular response was quantified by measuring reactive oxidative species (ROS) and by analyzing mitochondrial morphology. Control experiments established a baseline ROS response to hazardous blue light exposure and also that red light resulted in no detectable ROS response. Under identical conditions, ROS response increased with time for all devices. However, different device spectra caused ROS to accumulate at different rates. When operating the devices in the same mode (day or night), cells accumulated ROS two to three times more slowly on exposure to frontlit electronic paper displays compared to backlit liquid crystal displays. With increasing ROS accumulation, mitochondrial morphology shifted from elongate interconnected features typically observed under normal conditions to rounded disconnected features associated with oxidative stress response.