The optical radiation safety of various seasonal affective disorder (SAD) treatment lamps, sunrise simulators and daylight bulbs available on the UK market have been assessed using recognised guidelines. An analysis is included of the photometry of circadian entrainment by bright light therapy, with a justification for a melanopsin-based action spectrum for treatment efficacy. Parameters relating to both efficacy and phototoxicity risk, which are potentially relevant to bright light therapy treatment regimes, are considered. Unpredictable variations are highlighted which lead to the conclusion that several relevant photometric variables of treatment lamps need to be characterised to predict efficacy and potential hazards.
Get full access to this article
View all access options for this article.
References
1.
LewyAJLeflerBJEmensJSBauerVK. The circadian basis of winter depression. Proceedings of the National Academy of Science USA2006; 103(19): 7414–7419.
2.
RosenthalNESackDAGillinJCLewyAJGoodwinFKDavenportYMuellerPSNewsomeDAWehrTA. Seasonal affective disorder. A description of the syndrome and preliminary findings with light therapy. Archives of General Psychiatry1984; 41: 72–80.
3.
Baczynska K, O’Hagan J, Khazova M. Assessment of the optical radiation safety of seasonal affective disorder lamps: Proceedings of the Health Protection Conference 2009.
4.
LewyAKernHRosenthalNWehrT. Bright artificial light treatment of a manic-depressive patient with a seasonal mood cycle. The American Journal of Psychiatry1982; 139: 1496–1498.
5.
Vetter C, Juda M, Lang D, Wojtysiak A, Roenneberg T. Blue-enriched office light competes with natural light as a zeitgeber. Scandinavian Journal of Work Environment and Health 2011; 37(5): 437–445.
6.
BrainardGCHanifinJPGreesonJMByrneBGlickmanGGernerERollagMD. Action spectrum for melatonin regulation in humans: evidence for a novel circadian photoreceptor. Journal of Neuroscience2001; 21: 6405–6412.
7.
ThapanKArendtJSkeneDJ. An action spectrum for melatonin suppression: evidence for a novel non-rod, non-cone photoreceptor system in humans. Journal of Physiology2001; 535: 261–267.
8.
BersonDMDunnFATakaoM. Phototransduction by retinal ganglion cells that set the circadian clock. Science2002; 295(5557): 1070–1073.
9.
International Commission on Non-Ionizing Radiation Protection (ICNIRP). Guidelines on limits of exposure to broad-band incoherent optical radiation (0.38 to 3 mm). Health Physics1997; 73(3): 539–554.
10.
International Commission on Non-Ionizing Radiation Protection (ICNIRP). Guidelines on limits of exposure to ultraviolet radiation of wavelengths between 180 nm and 400 nm (incoherent optical radiation). Health Physics2004; 87(2): 171–186.
11.
SlineyDWolbarshtML. Safety with Lasers and Other Optical Sources, New York: Plenum Press, 1980.
12.
Commission International de l’Eclairage (CIE). The Basis of Physical Photometry. CIE Publication 18.2. Paris: CIE, 1983.
13.
Commission International de l’Eclairage. CIE Collection in Photobiology and Photochemistry 2000 Blue-light Photochemical Retinal Hazard. CIE Publication 138/1. Vienna: CIE, 2000.
14.
RevellVLSkeneDJ. Light-induced melatonin suppression in humans with polychromatic and monochromatic light. Chronobiology International2007; 24(6): 1125–1137.
15.
MainsterMATurnerPL. Blue-blocking IOLs decrease photoreception without providing significant photoprotection. Survey of Ophthalmology2010; 55(3): 272–289.
16.
DIN. Optical Radiation Physics and Illuminating Engineering – Part 100: Non-visual Effects of Ocular Light on Human Beings – Quantities, Symbols and Action Spectra. Berlin: Lighting Technology Standards Committee (FNL) in the DIN, 2009: 16.
17.
LallGSRevellVLMomijiHAl EneziJAltimusCMGulerADAguilarCCameronMAAllenderSHankinsMWLucasRJ. Distinct contributions of rod, cone, and melanopsin photoreceptors to encoding irradiance. Neuron2010; 66(3): 417–428.
18.
Peirson S. Personal communication. Relating that Original Data on the Melatonin-Suppression Action Spectrum (from Reference 6) had been Refitted and Shown to be Consistent with a Melanopsin Action Spectrum with Maximal Sensitivity to 476 nm at the Retina. 2011.
19.
HankinsMWLucasRJ. The primary visual pathway in humans is regulated according to long-term light exposure through the action of a non-classical photopigment. Current Biology2002; 12(3): 191–198.
20.
ReaMSFigueiroMGBiermanABulloughJD. Circadian light. Journal of Circadian Rhythms2010; 8(1): 2–2.
21.
KreuterABlumthalerM. Stray light correction for solar measurements using array spectrometers. Review of Scientific Instruments2009; 80(9): 096108–096108.
22.
LehmanBWilkinsABermanSPoplawskiMMillerJ. Proposing measures of flicker in the low frequencies for lighting applications. Leukos2011; 7(3): 189–195.
