This study documented the levels of microplastics in three commercially important small pelagic fish species in South African waters, namely European anchovy (Engraulis encrasicolus), West Coast ...round herring (Etrumeus whiteheadi) and South African sardine (Sardinops sagax). Data suggested variation between species with a higher concentration of microplastics for S. sagax (mean of 1.58 items individual-1) compared to Et. whiteheadi (1.38 items individual-1) and En. encrasicolus (1.13 items individual-1). The occurrence of microplastics was also higher for S. sagax (72%) and Et. whiteheadi (72%) compared to En. encrasicolus (57%). Microfibres accounted for 80% of ingested microplastics (the remainder were plastic fragments) with the main ingested polymers being poly(ethylene:propylene:diene) (33% occurrence), polyethylene (20%), polyamide (20%), polyester (20%) and polypropylene (7%). The abundance of ingested items was not significantly correlated with fish caudal length or body weight, and spatial investigation indicated an increase in the abundance of ingested items from the West to the South coast. Etrumeus whiteheadi is proposed as a bio-indicator for microplastics for South Africa.
An investigation into the abundance and distribution of meso- and microplastics within the Port of Durban was conducted using a static immersible water pump and particle filtration system to collect ...meso- and microplastics from the water column, microplastics from sediment samples and corresponding CTD. Microplastics were detected in all samples under investigation. Results suggest that sewage overflow, stormwater drains, port operations, followed by rivers are input areas for mitigation to focus on. Identifying meso- and microplastics inputs, baselines and distribution allow for long term monitoring and management in a harbour environment. This can potentially contribute to the control and regulation of small plastics particles in harbours, and the subsequent transport of these pollutants via dredged material into other ecosystems.
•Considerations for microplastic monitoring in relation to dredging, a Port of Durban perspective•Sampling of meso- and microplastics from near surface waters and microplastics in sediment•Microplastics were detected in all water and sediment samples from the Port of Durban.•Sewage overflow, storm water drains, operational activity and rivers all contributed to plastic contamination.