Not Always an Easy Win:The Effectiveness of a Ballot Bin Experiment to Prevent Cigarette Butt Littering

This paper presents the results of two behavioural interventions aimed at reducing cigarette butt littering which is a significant environmental pollutant. The interventions were priming – spraying shoeprints on the pavement leading to the nearest bin – and gamification – replacing two litter bins with two ballot bins. This experiment used a before-and-after uncontrolled experimental design and was conducted at a Bratislava transportation hub. Our results show that two interventions did not prove to be effective. The possible reasons are highly heterogeneous intervention group at the transportation hub, the effects of the pandemic and lockdown during which the experiment took place.