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Retinal phototoxicity and the evaluation of the blue light hazard of a new solid-state lighting technology.

ABSTRACT: Exposure Limit Values (ELV) for artificial lighting were defined in order to prevent light-induced damage to the retina. The evaluation of the lighting devices include the correction of their spectra by the B(?) function or blue light hazard function, representing the relative spectral sensitivity of the human eye to the blue light. This weighting function peaks between 435 and 440?nm. In this study we evaluate a new generation of light emitting diode (LED), the GaN-on-GaN (gallium nitride on gallium nitride) LED, that present an emission peak in the purple part of the spectrum. Wistar rats were exposed to GaN-on-GaN and conventional diodes at different retinal doses (from 2.2 to 0.5?J/cm²). We show that GaN-on-GaN diodes are more toxic than conventional LED for the rat neural retina and the rat retinal pigment epithelium, indicating that the BLH (blue light hazard) weighting is not adapted to this type of diodes. One of the reasons of this increased toxicity is the effects of shorter wavelengths on mitochondria polarization. We also show that the threshold of phototoxic retinal dose in the rat (fixed at 11?J/cm², BLH weighted) is overestimated, suggesting that the values used for regulations, calculated in primates using the same methods than in rats, should be revised.

SUBMITTER: Jaadane I

PROVIDER: S-EPMC7174369 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Retinal phototoxicity and the evaluation of the blue light hazard of a new solid-state lighting technology.

Jaadane Imene I Villalpando Rodriguez Gloria G Boulenguez Pierre P Carré Samuel S Dassieni Irene I Lebon Cecile C Chahory Sabine S Behar-Cohen Francine F Martinsons Christophe C Torriglia Alicia A

Scientific reports 20200421 1

Exposure Limit Values (ELV) for artificial lighting were defined in order to prevent light-induced damage to the retina. The evaluation of the lighting devices include the correction of their spectra by the B(λ) function or blue light hazard function, representing the relative spectral sensitivity of the human eye to the blue light. This weighting function peaks between 435 and 440 nm. In this study we evaluate a new generation of light emitting diode (LED), the GaN-on-GaN (gallium nitride on ga ...[more]

PMID: 32317708

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Retinal phototoxicity and the evaluation of the blue light hazard of a new solid-state lighting technology.

Publications

Retinal phototoxicity and the evaluation of the blue light hazard of a new solid-state lighting technology.

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