“It is Raining Plastic” is a May 14, 2019 US Geological Survey report. This report states that microplastic particles were found in more than 90 percent of atmospheric wet deposition samples collected from five sites in the Denver and Boulder urban corridors in Colorado.
“… The plastic materials were mostly fibers that were only visible with magnification … Plastic particles such as beads and shards were also observed with magnification … The mass of plastic … was not large enough to weigh or reliably estimate. Developing a routine capability to calculate plastic wet-deposition loads is not possible with current (2019) technology … How these plastic materials are accumulating and being assimilated in the environment and biota is unclear. Moreover, the potential effects of these materials on biota is not understood. Conclusions: It is raining plastic. Better methods for sampling, identification, and quantification of plastic deposition along with assessment of potential ecological effects are needed …”