A small number of studies have demonstrated that industrial wastewaters significantly increase the microplastic (MP) load in the receiving environment. Additionally, nothing is known about the quantity, nature, and eventual fate of MPs in the WWTPs where these wastewaters are treated. There is no research in this topic that has been published in our nation's worldwide literature. It is evident that both in our country and internationally, there is a need for systematic research on this subject. The proposed study is designed to take advantage of the fact that OIZs are businesses where it is possible to evaluate both the wastewater that results from a mixing of many sectors and the wastewater of particular industries individually. The unique contribution of this work is to fill a gap in the literature by identifying MPs in process wastewaters from industrial processes based on mixed OIZ and for various industrial sectors. The process wastewaters from the various sectors will also be assessed before and after the pre-treatment, and samples will be taken throughout the day to assess the impact of the pre-treatment procedures and daily variations on MP levels. The proposed project will examine the impact of wastewater treatment on these findings and produce comparable results. It will make an original contribution to the literature by comparing the amounts and compositions of MPs in process wastewater from selected industries in two different OIZs with MPs in wastewater from the entire OIZ. In two OIZs in Ankara, ASO 1st OIZ and ASO 2nd and 3rd OIZ, one of which lacks a WWTP and the other of which runs one of the WWTPs with the largest capacity, MP determinations from wastewater will be done. With samples to be taken from the mixed wastewater of OIZs, the MP amounts and composition of the loads carried by these firms to the municipal canal (ASO 1st OIZ), AAT (ASO 2nd and 3rd OIZ), and Ankara Stream (ASO 2nd and 3rd OIZ) will be determined. In this regard, the study's findings will guide other OIZs in our state, information on MPs originating from industrial wastewater in our country, and help fill the aforesaid gap in the worldwide literature.

The project started on September 15, 2021 and was completed on September 15, 2022.

Project outputs:

• Oğuzhan Altuntaş, Ozan Karakurt, F. Dilek Sanin "Occurrence of Microplastics in Industrial Wastewaters" 6th Eurasia Waste Management Symposium, 24-26 October 2022, İstanbul, Turkey.