Microplastics from BioSolids (Marketed as Natural Fertilizer) Can Carry Dangerous Pollutants Into the Air
By Eurasia Review:
“According to estimates by the U.S. Environmental Protection Agency, over 2 million dry metric tons of biosolids — roughly half of the total amount collected by wastewater treatment plants — are applied to land each year. As a result, microplastics in these biosolids have the chance to reenter the environment.
Because the plastics could carry other pollutants from the wastewater they originated from, they can be potentially dangerous when inhaled. So, Sanjay Mohanty and colleagues wanted to investigate how wind could pick up and transport microplastic particles from biosolid-treated agricultural fields.
The team analyzed airborne microplastics in wind-blown sediments that were gathered during wind-tunnel experiments on two plots of biosolid-treated land in rural Washington state. The researchers discovered that these wind-blown sediments contained higher concentrations of microplastics than either the biosolids or the source soil itself.
This enrichment effect is caused by the plastic particles being less dense than soil minerals, such as quartz, and less “sticky” — they’re not trapped as easily by moisture as the soil minerals are. As a result, microplastics can be picked up by a breeze more easily than soil minerals, and winds that might not be strong enough to kick up dust could still be introducing microplastics into the air.”