Atmospheric Microplastics: The Hidden Chemical Threat in Urban Air

Abstract

Atmospheric microplastics (MPs) represent an emerging environmental contamination pathway with significant implications for urban air quality and human health. This comprehensive review synthesizes current knowledge on the occurrence, distribution, and chemical characteristics of atmospheric MPs in urban environments based on verified scientific literature. MPs are ubiquitously present in atmospheric deposition across global urban areas, with concentrations ranging from 2-1008 particles/m²/day based on documented studies. Primary sources include synthetic textile fibers, plastic waste degradation, and vehicular emissions. Fibrous morphologies dominate atmospheric MP samples (>90% in most studies), with synthetic polymers including polyethylene terephthalate (PET), polypropylene (PP), and polyethylene (PE) being most prevalent. Atmospheric transport enables long-range distribution of MPs, allowing contamination of remote environments hundreds of kilometers from urban sources. Health implications are concerning as particles <10 μm can penetrate deep into respiratory tissues, potentially causing oxidative stress and inflammatory responses. Current analytical methods primarily rely on FTIR and Raman spectroscopy for definitive polymer identification. Urgent needs include standardized sampling protocols, improved analytical techniques, and comprehensive health risk assessments to understand the full implications of atmospheric MP pollution in urban environments.