Microplastics in an urban wastewater treatment plant: The influence of physicochemical parameters and environmental factors

This paper presents the abundance, concentration and variability of microplastics (MP) in an urban wastewater treatment plant (WWTP), according to different water parameters and environmental factors, their possible sources and removal efficiency. A total of 352.6 L of wastewater from four stages of...

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Detalles Bibliográficos
Autores: Bayo Bernal, Francisco Javier, Olmos Espinar, Sonia, López Castellanos García, Joaquín
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
País:España
Institución:Universidad Politécnica de Cartagena(UPCT)
Repositorio:Repositorio Digital UPCT
OAI Identifier:oai:repositorio.upct.es:10317/13753
Acceso en línea:http://hdl.handle.net/10317/13753
https://www.sciencedirect.com/science/article/pii/S004565351931817X
Access Level:acceso abierto
Palabra clave:Microlitter
Microplastic
Wastewater treatment plant
Low-density polyethylene
Tecnologías del Medio Ambiente
3308 Ingeniería y Tecnología del Medio Ambiente
Descripción
Sumario:This paper presents the abundance, concentration and variability of microplastics (MP) in an urban wastewater treatment plant (WWTP), according to different water parameters and environmental factors, their possible sources and removal efficiency. A total of 352.6 L of wastewater from four stages of the treatment process were processed following a standardized extraction protocol by density separation, trinocular microscopic identification and polymeric analysis by Fourier transform infrared spectroscopy. MP comprised a 46.6% of total microlitter, with a statistically significant removal of 90.3% in the final effluent of the WWTP. Five different shapes were isolated; i.e. fragment, film, bead, fiber, and foam. The most prominent MP forms in the final effluent were fragments and fibers, with the most common size class being 400e600 mm. Seventeen different polymer families were identified, with low-density polyethylene being the most prevalent one (52.4%) in a film form (27.7%), mostly from agriculture greenhouses near the sewage plant and single plastic bags (it is noted that only a year ago consumers are charged for them in Spain). Influent wastewater with high concentrations of suspended solids proved to have a low MP burden with a larger MP size, possibly due to a hetero-aggregation with particulate matter. Agglomeration of polystyrene and polyethylene terephthalate with organic material is also suggested, both with surface energies higher than 25mNm 1 enough for a high biofouling rate. The sewage plant cushions sharp-point microplastic concentrations during the warm season, allowing a stable performance of the WWTP.