A Blue-Enriched Light Intervention Counteracts the Alertness Decrement Among Mine Workers on Extended 12-Hour Night Shift Periods.

Publication Type:

Journal Article

Authors:

Marc Hébert; Lavigne, Andrée-Anne; Auclair, Julie; Martin, Jeanne-Sophie; Francis, Kimberley; Gagnon, Justine Dumoulin; Dubois, Marc-André; Laberge, Luc

Source:

J Occup Environ Med, Volume 65, Issue 7, p.584-589 (2023)

Keywords:

Attention, Circadian Rhythm, Humans, Miners, Sleep, Work Schedule Tolerance

Abstract:

OBJECTIVE: The aim of the study is to assess whether a blue-enriched light intervention improves nocturnal alertness and daytime sleep of night workers.METHODS: Thirteen miners performing 12-hour night shifts for 12 consecutive nights were exposed to a baseline and a blue-enriched light condition. All subjects wore an actigraph and completed a Psychomotor Vigilance Task at the beginning and at the end of each shift. Data were analyzed with linear mixed models.RESULTS: In the blue-enriched light condition, the daily increase in median reaction time (RT), mean RT, slowest 10% of RT, and fastest 10% of RT was lower than that observed in the baseline condition between day 1 and 12 ( P ≤ 0.05).CONCLUSIONS: The addition of blue-enriched light during a long period of extended night shifts counteracts most of the daily decline in nocturnal alertness observed in the standard lighting condition, irrespectively of sleep duration and sleep efficiency.