Spatio-temporal variation of microplastic along a rural to urban transition in a tropical river. (15th November 2021)

• Record Type: Journal Article
• Authors: Chen, Hui Ling; Gibbins, Christopher Neil; Selvam, Sivathass Bannir; Ting, Kang Nee
• Is Part Of: Environmental pollution. Volume 289(2021)
• Publication Date: 2021-11-15
• Subjects: Microplastics -- Surface water -- Spatial variation -- Temporal variation -- Discharge -- Suspended sediment concentration; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2021.117895
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Microplastic pollution is widely recognised as a global issue, posing risks to natural ecosystems and human health. The combination of rapid industrial and urban development and relatively limited environmental regulation in many tropical countries may increase the amount of microplastic entering rivers, but basic data on contamination levels are lacking. This is especially the case in tropical South East Asian countries. In this paper, the abundance, composition and spatio-temporal variation of microplastic in the Langat River, Malaysia, were assessed, and the relationship between microplastic concentration and river discharge was investigated. Water samples were collected over a 12-month period from 8 sampling sites on the Langat, extending from forested to heavily urbanised and industrial areas. All 508 water samples collected over this period contained microplastic; mean concentration across all sites and times was 4.39 particles/L but extended up to 90.00 particles/L in some urban tributaries. Most microplastics were secondary in origin, and dominated by fibres. Microplastic counts correlated directly with river discharge, and counts increased and decreased in response to changes in flow. A time-integrated assessment of the microplastic load conveyed by the Langat suggested that the river is typically (50 % of the time) delivering around 5 billion particles per day to the ocean. The positive correlation between the concentration of microplastics and suspended sediments in the Langat suggested that continuously logging turbidity sensors could be used to provide better estimates of microplastic loads and improve assessment of human and ecological health risks. Graphical abstract: Image 1 Highlights: Microplastics in the Langat were dominated by fibres. Microplastic concentrations varied spatially and increased with urbanisation. Microplastic concentrations increased and decreased in response to flow. The Langat delivers an estimated 5 billion particles to the ocean per day. Microplastic concentrations correlated with suspended sediment concentrations.