The increasing pollution leads to the deterioration in the water quality of the region as well as the quality of the recreation areas in parallel with the meteorological and hydrodynamic conditions in seas. Therefore, plastic packages and plastic wastes being formed later on, no matter how meticulously they are collected, may lead to adverse effects on marine ecosystems in terms of their content. In coastal areas where macro plastics are detected, the entrance of materials into the marine ecosystem is very easy as a result of climatic and abiotic factors. The macro plastics that reach seas and oceans disintegrate in time and get a microplastic size and thus pose a threat for the marine organisms. This study aims to determine the possible entrance ways of macro and micro plastics, which were detected after they had been dimensioned in coastal area, into the marine ecosystem and their possible effects on living ecosystem on Istanbul coastal area. The studies, which have newly been started on microplastics, reveal the need for making a policy by predicting the conditions of globalized world apart from the country conditions. The role of researchers in the monitoring of plastic pollution will increase in the coming years, and the truly "big" data they document must become part of the science of plastic pollution. For the present, it is real that a few scientists around the Turkey are engaged in attempting to understand the consequences seas.