Plastic pollution is increasingly becoming a threatening problem worldwide, with highlighted health risks associated with plastic waste incineration. Among the immediate measures to address this problem, proper recycling of PET bottles stands out as a pertinent strategy. Considering the urgent need for administrative-led reforms, we assessed the separation rates of PET bottle caps and labels in a government office in Japan, which revealed a concerning fact; only 59.3% had both caps and labels removed and properly separated. Thus, one potential solution is the use of Nudges, which are effective methods for promoting behaviors such as healthy actions. Since both health and environmentally conscious behaviors involve choices across different time points, leveraging insights from Nudges developed in the field of health behavior to environmental behaviors are considered crucial even from a health promotion perspective.