Thursday 2 September 13:15 > 13:30

Interactions between microplastics and organic pollutants: Effects on transport and bioaccumulation: from the lab to the environment

Prof. Yolanda Picó Dr. Julian Campo Prof. Ahmed H Alfarhan Prof. Mohamed A. El-Sheikh Prof. Damià Barceló
Session: 9(P) Microplastics in water treatment: fate, toxicity assessment and removal technologies
CEST ID: 441 ROOM: B Paper Presentation

Microplastics (MPs) have the ability to extract/preconcentrate other contaminants from water samples and could also act as vectors to other environmental compartments. The occurrence and distribution of MPs in different points of Al-Jubail, the most important industrial city, and the second biggest after Riyadh have been studied. The sampling points included those of the runoff channel system that transports treated water from different industries, and that cross longitudinally the city up to the sea. MPs were visually identified after filtration and digestion of the organic matter and the chemical composition was identified by FTIR. Furthermore, polycyclic aromatic hydrocarbons (PAHs) and perfluoroalkyl substances (PFASs) were selected as a model toxic hydrophobic organic contaminants to study the MPs capacity to sorb them. The relative bioavailability of dissolved and MP-sorbed phenanthrene, fluoranthene, prefluoroctane sulfonic acid (PFOS) and perfluoroctanoic acid (PFOA) under co-exposure conditions was assessed. To this, high density polyethylene (PE) microspheres were purchased from “Gran Velada” in dry powder form, in 180–221 μm (’PE-200′) range. These spheres were put in contact with PAHs and PFASs dissolved in water according to their solubility capacity. Results pointed out the presence of MPs of different sizes, colours and forms in the water samples taken. The most common plastics were whit fibers >0.5 mm. However, there were many different types of plastics mostly <200 µm. Regarding the type of polymer, only 4 polymer types, PE, PP, PET and PS were determined based on a comparison with infrared spectrogram databases. The sorption experiments demonstrated that both PAHs and PFASs are absorbed in the surface of the MPs. Then, the effects of this adsorption in the aquatic biota needs further research. This study can be used as a reference to better understand the impacts of MPs in artificial surface channels and ponds affected by the discharges of wastewater treatment plant. Furthermore, results confirmed the importance of polymer type, particle size and temperature as determining factors for the degree and mechanism of hydrophobic organic contaminant sorption from water to MP. Acknowledgement - The authors thank the financial support from the project number (RSP-2021/11) King Saud University, Riyadh, Saudi Arabia.