Dupepe, L. M., Dauchy, R. T., McAndrew, D. et al. 2020. Eliminating light-at-night contamination during a lab animal facility renovation. Laboratory Animal Science Professional 8(5) (September/October), 60-62.

Relocating laboratory animal research from one animal facility room to another in advance of major renovations can be a daunting task for scientists and animal care personnel alike. This is especially so regarding controlled lighting and the elimination of light-at-night (LAN) contamination. Previous studies demonstrated that an animal room nighttime ‘light leak’, or LAN-contamination, of as little as 0.2 lux photometric illuminance (0.08 μW/cm2, photometric irradiance) at ocular level (within cage) during dark phase was sufficient to elicit disruptions in circadian rhythms of rodent metabolism and physiology, and to stimulate human breast tumor growth in nude rats. Prior to initiation of the renovation project, two new animal rooms were identified and upgraded to temporarily house the study animals of the five investigators affected. By mutual consensus, the decision was made to install a blackout curtain over the animal room door using a cornice sealed at the sides and top to prevent light entry. The inexpensive unit was simple to operate for room entry/access and maneuverability, easy to maintain and clean, and provided immediate and complete LAN-decontamination during dark phase (0 lux). Study animals were relocated to the new facility within minutes, reducing potential stress and without disrupting important ongoing cancer research studies.