Blue blocker glasses impede the capacity of bright light to suppress melatonin production
Article first published online: 18 MAY 2006
Journal of Pineal Research
Volume 41, Issue 1, pages 73–78, August 2006
How to Cite
Sasseville, A., Paquet, N., Sévigny, J. and Hébert, M. (2006), Blue blocker glasses impede the capacity of bright light to suppress melatonin production. Journal of Pineal Research, 41: 73–78. doi: 10.1111/j.1600-079X.2006.00332.x
- Issue published online: 28 JUN 2006
- Article first published online: 18 MAY 2006
- Received December 9, 2005; accepted March 28, 2006.
- shift workers;
Abstract: Blocking morning light exposure with dark goggles can contribute to the adjustment to night work but these glasses are incompatible with driving. Recently, it was discovered that the biological clock is most sensitive to short wavelengths (blue light). Therefore, we tested the hypothesis that cutting the blue portion of the light spectrum with orange lens glasses (blue blockers) would prevent the light-induced melatonin suppression, a test broadly used as an indirect assessment of the circadian clock sensitivity. Fourteen normal subjects were exposed at night to a 60 min bright light pulse (1300 lx behind filters) between 01:00 and 02:00 hr while wearing orange lens glasses (experimental condition) or grey lens glasses (control condition). The amount of salivary melatonin change observed during the light pulse was compared with a melatonin baseline obtained the night before. Although both glasses transmitted the same illuminance (1300 lx) but at an irradiance 25% higher for the orange lens (408 μW/cm2) compared with the grey lens (327 μW/cm2), a non-significant increase of 6% (95% CI, −20% to 9%) was observed with the orange lens whereas a significant (P < 0.05) reduction of 46% (95% CI, 35–57%) was observed with the grey lens. Blue blockers represent an elegant means to prevent the light-induced melatonin suppression. Further studies are needed to show that these glasses, which are suitable for driving, could facilitate adaptation to night work.