Ballot Butts: Nudging Towards Pro-Environmental Behaviour


  • Anouk Hartmans University of Ljubljana
  • Lucija Karnelutti University of Ljubljana
  • Leon Žužek University of Ljubljana
  • Sabina Pajmon University of Ljubljana
  • Toma Strle University of Ljubljana



Escalating environmental issues underscore the need for innovative waste management solutions. In 2019, only a quarter of the 6 trillion butts were properly discarded, causing great soil and water contamination [1]. This pilot study investigates the efficacy of a behavioral nudge—a voting box where cigarette butts are used as ballots—to reduce littering on college campuses. Drawing from "The Little Book of Green Nudges" [2] and principles of behavioral science, this intervention seeks to influence smoker behavior through engaging and socially relevant disposal methods.

Our initial observation of the campus setting show 30% of butts were thrown on the ground despite bins being present. After observations, we created our own nudge using the EAST framework, comprised of four ideals - Easy, Attractive, Social, and Timely. The voting box, where people vote with their butts for one of two alternatives (example: Kendrick vs. Drake) was designed to be accessible, visually appealing, and strategically placed, all aimed at encouraging participation.


We utilized four recommended steps to make a nudge successful.

  1. Behavior identification: focusing on a specific non-environmental behavior (improper cigarette disposal)
  2. Context analysis: studying the context and underlying motivations for this behavior, drawing from Rifkin et al. [3], who demonstrated how dueling preferences can influence decisions.
  3. Design: designing the voting box to be aesthetically pleasing and placing it in an area frequented by smokers.
  4. Social engagement: crafting voting prompts that resonate with smokers' identities and preferences, encouraging participation and proper disposal.
  5. Observing the efficiency of the nudge by comparing the ratio of littered cigarettes vs. properly discarded cigarettes before and after the implementation of the nudge.


This study hypothesizes that the interactive nature of the voting box will significantly alter disposal behaviors by providing a tangible and immediate way for smokers to participate in larger social dialogues through the act of disposing their cigarette butts properly.

As this is an anticipatory study, no results have been gathered yet. The next phases will involve monitoring and evaluation of the impact of the voting box on littering behavior, which will be crucial for assessing the viability and scalability of such nudges in promoting sustainable environmental practices.

Possible implications

During our research, we realized there are many practical implications for nudging. As there is still a dearth of information regarding the duration of nudging effects, we think nudges could be excellent in short-term environments like festivals, concerts, and other events.


This pilot research study was partly supported by The Green Nudge project (the European Union - NextGenerationEU, and Republic of Slovenia, Ministry of Higher Education, Science and Innovation).



[1] D. S. Green, A. D. W. Tongue, B. Boots, “The ecological impacts of discarded cigarette butts,” Trends in Ecology & Evolution, vol. 37, no. 2, Oct. 2021, doi:

[2] U. N. Environment, “The Little Book of Green Nudges,” UNEP - UN Environment Programme, Aug. 27, 2020.

[3] J. R. Rifkin, K. M. Du, and J. Berger, “Penny for Your Preferences: Leveraging Self-Expression to Encourage Small Prosocial Gifts,” Journal of Marketing, Jun. 2020, doi: