New research published in the journal Environmental Science & Technology reveals that in 2020 alone, some 74 metric tons of microplastics – that is, the plastic particulates released from waste into the environment – fell on the city of Auckland in New Zealand via rainfall.

The first peer-reviewed study of its kind to calculate the total mass of microplastics in a city’s air, the paper found that the pollution equivalent of three million plastic bottles falls on Auckland in an average year – a truly astounding level that is much higher than generally accepted estimates.

Researchers say the global prevalence of airborne microplastics appears to be much higher than previously believed. Most of these particulates are too small to be seen with the naked eye, though scientists were able to identify them using a colored, light-emitting dye.

For analysis, researchers also applied heat treatment, which allowed them to calculate an aggregate mass of the particulates in terms of volume and tonnage. (Related: The average person consumes a credit card’s worth of microplastics every week in tainted food.)

“The smaller the size ranges we looked at, the more microplastics we saw,” said Joel Rindelaub, the study’s lead author and a chemical scientist at The University of Auckland. “This is notable because the smallest sizes are the most toxicologically relevant.”  […]

Microplastics are everywhere, including in New Zealand’s rainfall — Rangitikei Environmental Health Watch