Impact of Extended Exposure to LED Light on Retinal Metabolome, Cognitive Function, and Behaviour

Background: Exposure to short-wavelength LEDs, which are increasingly common in the digital era, particularly between 400 nm and 490 nm, can negatively impact the visual system and retinal metabolome. Thisstudy aimed to determine the effects of blue light exposure on retinal metabolomic changes and behaviour in rodents via gas chromatography/mass spectrometry (GC/MS). Methodology: A total of 18 healthy adult male Wistar rats were randomly divided into six groups (n=6), three control (NC) groups (n=3), and three experimental (EXP) groups (n=3). The EXP animals were exposed to a 4-hour (4.00–8.00 pm) light cycle of blue LED light with uniform illumination (450–500 lux) throughout 14, 21, and 28 days. Postexposure, the rats were subjected to behavioural tests via the passive avoidance test (PAT). The animals were subjected to the elevated plus maze (EPM) test, and retinal tissue was removed to evaluate the metabolomic profile via GC-MS. Results: The PAT showed a notable difference in latency (p=0.0317) between the groups. The EXP to blue light resulted in worsened motor memory and a longer latency to enter the dark compartment (DC). The EPM test did not reveal noteworthy variance in the time spent in the closed arm (TSICA) across sessions (p=0.1801). When retinal metabolites were compared between the groups, there was a notable difference (p < 0.0001), with the experimental groups having different levels of hydroxylamine. Conclusion: Extended exposure to blue LED light can cause molecular changes in the retina that may lead to significant structural damage over time. This damage can result in alterations in learning and motor memory, which can persist for up to 28 days.