A Study on the Phototoxic Effect of LED Bulbs on the Zebrafish (Danio rerio) Embryos

Light emitting diodes (LEDs) constitute a recent light source right from home, office lightings. The advantage of the LEDs is that they offer superior light intensity, efficiency even being smaller than the traditional lighting system. LEDs are highly specific when it comes to wavelengths of light. The current investigation assessed the effects of various light wavelengths emitted by light-emitting diodes (LEDs) on the development of zebrafish at the embryo and larval stages. The coloured LEDs used had the wavelength of 630 nm (red), 450 nm (blue), 530 nm (green) and yellow (585) white light (full spectra). Zebrafish has become the leading model organism in research to investigate human diseases, high-throughput drug screening, assessing toxicity and biological rhythms. The large number of eggs which are transparent and with its low maintenance cost makes zebrafish as a popular model organism in contemporary biomedical research. The present study investigated the phototoxic effect of different wavelengths of light which induced apoptosis in zebrafish 5 dpf larva. The apoptosis caused by the phototoxicity of LEDs were assessed by using the vital dye Acridine orange (AO). Often AO is used as a marker of apoptotic cells. The fluorescent images recorded were manipulated and analysed using the ImageJ software. The results showed that among the different LEDs, blue light indeed caused more apoptosis in the 5dpf larva. The study significantly contributes to toxicology by presenting a comparative analysis of LED phototoxicity across various wavelengths, which is crucial given the pervasive use of LED technology.​