One interesting implication of this is that most discussions about microplastics focus on food or ocean pollution, but urban air exposure might actually be much more constant.

Tire abrasion is happening everywhere there is traffic, so people in cities are probably inhaling these particles daily without noticing it.

It raises question about particle size distribution. Nanoplastics behave very differently from larger particles and may interact with biological tissues in ways that are still poorly understood...

Urban environments might therefore be an important long-term exposure pathway that hasn’t been studied as much as water or seafood contamination