Microplastics in the Air and Their Associated Health Impacts

Microplastics (MPs) have recently emerged as an important environmental contaminant. Due to their environmental persistence and deep penetration into the body, microplastics may cause harmful health effects such as oxidative stress, cytotoxicity, disruption in the immune system, neurotoxicity, microbial infections, etc. Microplastics are ubiquitous and have been recovered from regions far from their primary sources of origin. They are generally defined as plastic fragments having a diameter ranging between 1 μm to 5 mm. Microplastic exists in different shapes, sizes, and colors, determined by its origin and production process, and thus varies greatly in abundance depending on the source of origin. The chemical composition of the MPs depends on the type of polymer used to make the plastics from which MPs are eventually formed. Many scientific investigations have been carried out to document the effects of MPs in marine and other aquatic ecosystems. However, there exists an information gap about their quantitative assessment in the atmosphere, physical and chemical characteristics, and associated health impacts. Moreover, to examine their occurrence, transport, and risks to human health, more research-based studies are required to standardize sampling and identification protocols. In this chapter, based on the existing literature, we have discussed the characteristics of MPs present in the atmosphere, their possible route of exposure to the human body, and associated health effects.