Occurrence and transport of microplastics sampled within and above the planetary boundary layer

Miguel González-Pleiter; Carlos Edo; Ángeles Aguilera; Daniel Viúdez-Moreiras; Gerardo Pulido-Reyes; Elena González-Toril; Susana Osuna; Graciela de Diego-Castilla; Francisco Leganés; Francisca Fernández-Piñas; Roberto Rosal

doi:10.1016/j.scitotenv.2020.143213

Occurrence and transport of microplastics sampled within and above the planetary boundary layer

Sci Total Environ. 2021 Mar 20:761:143213. doi: 10.1016/j.scitotenv.2020.143213. Epub 2020 Oct 27.

Affiliations

¹ Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain; Departamento de Ingeniería Química, Universidad de Alcalá, Alcalá de Henares, E-28871 Madrid, Spain. Electronic address: mig.gonzalez@uam.es.
² Departamento de Ingeniería Química, Universidad de Alcalá, Alcalá de Henares, E-28871 Madrid, Spain.
³ Centro de Astrobiología, CAB (INTA-CSIC), Torrejón de Ardoz, Spain.
⁴ Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain; Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, 8600 Duebendorf, Switzerland.
⁵ Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain.

PMID: 33162145
DOI: 10.1016/j.scitotenv.2020.143213

Abstract

Nowadays, there is no direct evidence about the presence of microplastics (MPs) in the atmosphere above ground level. Here, we investigated the occurrence, chemical composition, shape, and size of MPs in aircraft sampling campaigns flying within and above the planetary boundary layer (PBL). The results showed that MPs were present with concentrations ranging from 1.5 MPs m^-3 above rural areas to 13.9 MPs m^-3 above urban areas. MPs represented up to almost one third of the total amount of microparticles collected. Fourier Transform Infrared Spectroscopy allowed identifying seven types of MPs with the highest diversity corresponding to urban areas. Atmospheric transport and deposition simulations were performed using the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Air mass trajectory analyses showed that MPs could be transported more than 1000 km before being deposited. This pioneer study is the first evidence of the microplastic presence above PBL and their potential long-range transport from their point of release even crossing distant borders.

Keywords: Airborne microplastics; Aircraft sampling; Atmospheric transport; Microplastics deposition; Planetary boundary layer.