We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Problems caused by microplastics in soil: Personal perspective
Summary
This perspective paper argues that microplastics in soil are an underappreciated legal and regulatory problem and presents experimental evidence showing polyethylene glycol caused water ponding and reduced infiltration by clogging soil pores. The author warns that microplastic polymer effects on soil hydrology could impair agricultural productivity.
In this perspective, I focus on problems caused by plastics or microplastics in soil that are based on my knowledge. I point out that contacts that I have had from lawyers and policy makers show that plastics in soil are going to become important legal and regulatory issues. I describe an experiment that I did with the microplastic, polyethylene glycol, added to soil, which showed that it caused ponding of water on the soil surface and reduced infiltration, probably due to the participation of the polymers of the microplastic in a process called solvation. The large, hydrated molecules apparently clogged the soil pores, preventing aeration. I also showed in the same experiment that polyethylene glycol increased the uptake of the toxic heavy metal, cadmium, into wheat plants. I end the perspective by describing a recent experiment that indicates that the Casparian strip is a likely barrier for the uptake by lettuce of polystyrene microplastics that are 200 nm in diameter. However, smaller particles might penetrate it, and we need more studies to determine the size of nanoparticles that can move through the Casparian strip and up to the shoot.