The problem is great enough that the UN has warned that microplastics pose a threat to human health, while the US has banned products from using plastic microbeads—often included to make cosmetic products slightly abrasive so they work as exfoliants. A recent study found that US waterways are now basically full of microplastics. In that study, the most common type found was thin plastic fibers from textiles, which accounted for around 71% of the total plastic pollution in the samples collected.