Airborne Microplastics in a Suburban Location in the Desert Southwest
KANCHANA CHANDRAKANTHAN, Pierre Herckes,
Arizona State University Abstract Number: 140
Working Group: Aerosol Chemistry
AbstractMicroplastics are rapidly emerging anthropogenic stressors that pose a potential threat to ecosystems and human health. They are defined as plastic particles that are less than 5 mm in size. Microplastics are either intentionally manufactured at a microscopic size or result from the fragmentation of larger plastic litter. While the ubiquitous nature of microplastics in water has been well documented, studies on their distribution in the air are limited. Microplastics in suspended particulate matter in the atmosphere is important in assessing microplastic contamination within a breathing zone. Owing to their small size and low material density, microplastics can be easily inhaled and pose a potential threat on humans. An additional concern arises from the additives used in plastic manufacturing and adsorbed hydrophobic organic pollutants such as Polycyclic aromatic hydrocarbons (PAHs). In addition to the concentration, it is important to understand the chemical composition of microplastics. Chemical characterization will yield information on the nature of the microplastics present and therefore provide an insight into their origin and toxicity.
Here we investigate and present results for the occurrence of microplastics in suspended particulate matter and total atmospheric fallout in a suburban location in the desert Southwest, and thereby aim to contribute to the limited existing knowledge of their occurrence in the air. Samples were collected, processed and microplastics were counted under an optical microscope to obtain quantitative information of their distribution in air. Microplastics were present in all collected suspended particulate and total atmospheric fallout samples ranging from between 0.02 to 1.1 microplastics/m3 (average concentration of 0.2 microplastics/m3) and 71 to 389 microplastics/m2/day (average deposition flux of 178 microplastics/m2/day) respectively. Micro-Raman spectroscopy was used to identify the chemical composition of microplastics in suspended particulate matter. Chemical characterization results revealed an array of polymers for the airborne microplastics.