A reliable method to determine airborne microplastics using quantum cascade laser infrared spectrometry

The number of studies dealing with airborne microplastics (MPs) is increasing but sampling and sample treatment are not standardized, yet. Here, a fast and reliable method to characterize MPs is presented. It involves the study of two passive sampling devices to collect atmospheric bulk deposition (...

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Detalles Bibliográficos
Autores: González Pleiter, Miguel, López-Rosales, Adrián, Ferreiro, Borja, Andrade, José, Fernández-Amado, María, López-Mahía, Purificación, Rosal, Roberto, Muniategui-Lorenzo, Soledad
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/716836
Acceso en línea:http://hdl.handle.net/10486/716836
https://dx.doi.org/10.1016/j.scitotenv.2023.169678
Access Level:acceso abierto
Palabra clave:Atmospheric microplastics
passive air samplers
quantum cascade laser
infrared spectrometry
LDIR
bulk deposition
Biología y Biomedicina / Biología
Descripción
Sumario:The number of studies dealing with airborne microplastics (MPs) is increasing but sampling and sample treatment are not standardized, yet. Here, a fast and reliable method to characterize MPs is presented. It involves the study of two passive sampling devices to collect atmospheric bulk deposition (wet and dry deposition) and three digestion methods (two alkaline-oxidative and an oxidative) to treat the samples. The alkaline-oxidative method based on KOH and NaClO was selected for a mild organic matrix digestion. In addition, some operational parameters of a high-throughput quantum cascade laser-based infrared device (LDIR) were optimized: an effective automatic tiered approach to differentiate fibres from particles (>90 % success in validation) and a criterion to establish positive matches when comparing an unknown spectrum against the spectral database (proposed match index > 0.85). The procedural analytical recoveries were very good for particles (82–90 %) and slightly lower for fibres (62–73 %). Finally, the amount and type of MPs deposited at a sub-urban area NW Spain were evaluated. Most common polymers were Polyethylene (PE), Polypropylene (PP) and Polyethylene terephthalate (PET). The deposition rates ranged 98–1220 MP/m2/day, ca. 1.7 % of the total collected particles. More than 50 % of the total MPs deposited were in the 20–50 μm size range, whereas fibres were mostly in the 50–500 μm size range