Preliminary Assessment of Microplastic Pollution Index: A Case Study in Marmara Sea

Abstract

Microplastics are global threat for marine environment, which originated from anthropogenic activities. Although human-induced effects on microplastics are well known, a holistic assessment has not been made. Here, we present the Microplastic Pollution Index (MPI); a fast, convenient, inexpensive and semi-quantitative tool for assessing land- and sea-based pressures on the sampling area. In this preliminary study, MPI were determined for eight different locations in Marmara Sea. According to the MPI results, The Marmara Sea is under the effect of several pressures such as urban and industrial wastewater, marine traffic, agricultural and residential activities on land. Furthermore, coastline morphology affects the retention time of water at the coastal zone. The highest MPI values were obtained from the lzmit and Bandit ma Gulfs, whereas the lowest value was found at inflow of the Dardanelle Strait. MPI values and surface water abundance values for each station showed a linear relation (R-2=0.60; F=7.619; DF=1, P<0.05). No correlation was found between MPI and microplastic abundance in water column and sediment. MPI is providing extensive information on microplastic pollution. The index can be useful to generate an effective monitoring strategy combating, restoring and protecting the coastal waters against the microplastic pollution.