Microplastics in Marine Sediments from Dar es Salaam Coast: Spatial Distribution and Characterization

Abstract

The purpose of the research was to determine the spatial distribution and characterization of microplastics in marine sediments of beaches along the Indian Ocean of Dar es Salaam coast. The sediment samples were extracted in triplicate using floatation method followed by digestion of organic debris, then analyzed using At-FTIR spectrophotometer and stereomicroscope. The mean concentrations of microplastics for Kijichi Beach were 700 ± 907 particles/m2 at 1 cm, 859 ± 839 particles/m2 at 5 cm and 590 ± 782 particles/m2 at 10 cm; from Palm Beach were 157 ± 15 particles/m2 at 1 cm, 130 ± 182 particles/m2 at 5 cm and 16 ± 0 particles/m2 at 10 cm; from Coco Beach were 167 ± 155 particles/m2 at 1cm, 104 ± 100 particles/m2 at 5 cm, 70 ± 86 particles/m2 at 10 cm; from Mbezi Beach were 115 ± 108 particles/m2 at 1cm, 74 ± 82 particles/m2 at 5 cm and 16 ± 0 particles/m2 at 10 cm. The microplastics were polypropylene, polyethylene, polyurethane, polyamide, polyvinyl chloride, polyethylene terephthalate, and polytetrafluoroethylene, in the form of fibres, fragments, sponges and pellets. The sediments were confirmed to be contaminated with microplastics with high amount at 1 cm compared to other profile location.