Apple Snails as Bioindicators of Microplastic Pollution in Singapore's Freshwaters

Microplastics (MPs) are persistent and ubiquitous environmental pollutants that can be difficult to monitor for their presence especially in water bodies. This study reports, for the first time, a quantified analysis of the abundance of MPs in Singapore’s freshwater environment, using the golden apple snail Pomacea canaliculata as a bioindicator. Snail samples were collected from six different freshwater locations around the island, and MPs present were identified via Fourier Transform Infrared Analysis, then subsequently quantified using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectroscopy. Results showed that Polyethylene is highest in pollution intensity at the central parts of Singapore, while Poly(methyl methacrylate) concentration is evenly distributed across all six sample sites while Nylon pollution is mostly concentrated along the shores. The results obtained can lead to insights on pollution levels, which is beneficial in implementing targeted cleaning-up measures and could allow analysis of the effectiveness of any existing approaches targeted at reducing MP pollution.