Musa Ilias Biala

This study used both quasi-experiment and contingent valuation survey to explore the applicability of deposit-refund system (DRS) to water-sachet litter management in Nigeria. In the experiment, a DRS was established to incentivize the participants to return emptied sachets of water. A contingent valuation survey of 454 sachet-water consumers selected using quasi-systematic sampling technique was conducted. Experimental results showed that the number of sachets returned by the experimental group – those subjected to DRS – was significantly greater than that of the comparison group – those not subjected to DRS. Logit regression results showed that refund size increased the odds of returning sachets by 42.0%. Increasing the redemption time decreased the odds of turning in sachets by about 16.0%. A one-minute increase in the time spent on redemption would result in about 2.4% decrease in the probability that participants would comply. Income decreased the odds of compliance by about 31.0%, while age reduced the odds of compliance by about 2.2%. These results imply that the DRS reduced water-sachet littering in the study area, and that income, refund amount, redemption time, age and perceived effectiveness of DRS influenced consumers’ compliance with DRS. Hence, an appropriate motivating DRS would reduce litter and its attendant problems, such as hygiene, plastic pollution, flooding, aesthetic loss, non-naturally degradable toxic compounds, degradation of natural habitat ant its endangered species. The government should, therefore, implement a DRS and set up recycling plants, or encourage private recycling firms, in order to accommodate used sachets that would end up piling up.

Littering has been a subject of inquiry by environmental economists, as well as social and environmental psychologists, each using a different theoretical and analytical toolkit. While economists see littering as an externality problem or a market failure, psychologists see it as a social behavior problem. Regardless of the discipline, both theories have a common goal: What factors affect littering behavior and how can it be curtailed? This paper, therefore, adopts theory-triangulation approach to review theories concerning littering. It concisely reviews the economist’s and the psychologist’s approaches to littering and their respective solutions. The finding from this review is that the psychological approaches to litter control are narrower in coverage than the economic approaches in that the former are applicable to smaller environmental settings or areas, such as school premises, office places, factories, and market places, as opposed to such lager settings as cities, states or the country at large to which economic instruments are usually applied. Despite the plethora of research extolling the virtues of economic approaches to litter control, their real-world application has not caught on. One of the factors responsible for this is the implementation costs and difficulty involved. The economic instruments are costlier than the psychological instruments, because the former cover a larger setting and entail a lot of bureaucracies. To better understand littering and find appropriate solutions to it, studies on littering should consider looking at littering holistically from this interdisciplinary perspective. Both the economist’s and the psychologist’s approaches to litter control should be synthesized for sustainable waste management. However, policymakers need to consider the available financial resources and the multifarious views of litter in policies relating to litter. An option for policymakers is to minimize those costs associated with implementing economic instruments.