Photooxidative molecular damage under blue light

The widespread adoption of artificial lighting has substantially increased human exposure to blue light across various environments, raising concerns about its potential adverse effects on human health. Over the past decades, blue light-induced biological responses have been investigated across multiple levels-from mechanistic studies of photoinduced reactive oxygen species generation to broader physiological consequences. Since all cellular and tissue-level effects ultimately originate from structural and functional alterations in molecular components, a comprehensive understanding of blue light-induced molecular damage is clearly warranted. This review summarizes current knowledge and recent findings on photooxidative molecular damage induced by blue light exposure, with a focus on the primary photochemical mechanisms of reactive oxygen species generation, blue light-sensitive endogenous photosensitizers, and the resulting oxidative damage to key biomolecules, including proteins, DNA and lipids. These insights collectively establish a more integrated framework for understanding how blue light compromises molecular integrity within cells.