Preliminary study on microplastic pollution in surface-water at Tallo and Jeneberang Estuary, Makassar, Indonesia

Microplastic is anthropogenic-based pollution that becomes a global problem, threatening the ecosystem and food security. Microplastic from land-based source can enter the ocean through estuarine waters. Makassar City with a population around 1.7 million people, provides possible sources of microplastic pollution in Makassar Strait through the flow of surrounding rivers, Tallo and Jeneberang in particular. Neuston net method was used to collect 18 surface-water samples from Makassar Estuaries for microplastic analysis. Fish gastrointestinal tracts were collected from 76 pelagic fish in study sites for microplastic analysis, using KOH digestive method. Surface-water samples from both Jeneberang and Tallo river estuaries positively contained microplastic (MPs) particles with abundance of 1.84±0.17 and 1.78±0.25 MPs m respectively. There is no difference between microplastic abundance on both estuaries using t-test statistic, but microplastic from both estuaries, in general, has different characteristics in shape and color. The higher abundance of microplastic in riverine part on both estuaries indicated that microplastic originated from land sources. Pelagic fish from both estuaries were also contained an average of 0.91 to 3.5 MPs individual with more than 50% of contamination level on most species. This result shows that estuary water in Makassar City have been contaminated by microplastic particles and have accumulated to pelagic fish as consumption fish, posing a threat to food safety and human health.