Role of Citizen Scientists in Environmental Plastic Litter Research—A Systematic Review

Abstract

In recent years, citizen science has proven to be an effective means of monitoring plastic litter, bring potential benefits to professional researchers and authorities, and create awareness on plastic pollution at a society level. This paper aims to review the advances of employing the citizen science approach for plastic litter evaluation and explore the research contributions of these initiatives and their impact at the society and environmental levels. A systematic search was undertaken using the main scientific paper databases and back-referencing from reviewed papers over a period of 10 years. Out of 221 papers found, only 94 papers that discussed plastic litter/waste and citizen science remained in the analysis. Geographically, 66% of the studies were concentrated in the Northern Hemisphere (mostly in USA). The majority were related to clean-up activities that analysed litter density, types, and potential sources. The results showed that citizens can provide data over large geographical regions and can be essential to researchers and authorities in implementing litter management policies. Citizen science programs are effective in creating awareness and increasing education regarding plastic litter pollution and impact. However, it is not clear if they can enhance behavioural changes after participation in field survey programs.