Microplastic (MP) Pollution in the Context of Occurrence, Distribution, Composition and Concentration in Surface Waters and Sediments: A Global Overview

Abstract

Microplastic (MP) pollutants are widespread and have been detected in both surface waters and sediments across the globe. At some places, MP abundance reached 90–100% of the samples sampled in surface waters. They (MP) have even reached the remote and pristine parts of the world. Plastic litters have outnumbered fish larvae and plankton at several places in the world. The increased abundance of MP was reported in surface waters close to larger cities and cities with higher population density, enclosed basins, gyres, dams/reservoirs and coastal areas. The Coastal Soya Island, South Korea (having 46,334 MP particles/m2) and the Pearl River Estuary, Hong Kong (having 5595 MP particles/m2), are the two MP pollution ‘hot spots’ in surface waters. MP pollutants are also widespread and detected in sediments of a wide range of aquatic environments including archipelagos, bays, channels, coasts, beaches, deep seas, estuaries, lagoons, rivers, shellfish farms and ship-breaking yards. At some places, MP abundance in sediments reached around 64% to 100% of the samples sampled. The Kachelotplate and Spiekeroog islands, Germany (having 38,000 MP particles/kg dw sediments) and Jakarta Bay, Indonesia (having 30,006 MP particles/kg dw sediments), are the two MP pollution ‘hot spots’ in sediments. Based on polymer shapes, the most commonly detected MPs in both surface waters and sediments are fibres, fragments, foams and films. On the other hand, based on polymer chemistry, the most commonly detected MPs in surface waters and sediments are polyethylene (PE), polypropylene (PP) and polystyrene (PS). To reduce impacts from plastic wastes and plastic pollution, a number of measures have been suggested.