Concerns about the prevalence of micro plastics in the world’s oceans are increasing rapidly. A study conducted in 35 US National Parks sampled beach sand for evidence of these microplastics. Not surprisingly, they found some… lots.
Microplastics, as discussed previously, are pieces of plastic less then 5 mm in size. They are ubiquitous throughout marine and aquatic ecosystems, likely coming from waste water treatment outfalls, and the laundering of synthetic clothes. They are associated with high concentrations of dangerous toxins and can be consumed by plankton, thus entering the food web.
The National Park study found microplastics at every sampling location, but found no correlation with distance to waste water treatment plants, urban centers or rivers. The inability to correlate trends with land variables leads me to think that the density of micro plastics in these remote areas is likely more closely linked to currents (both macro and micro) than land usage. The paper does discuss some of these trends in general terms (e.g. how upwelling in CA might keep microplastics from accumulating on the shore at the same rate as in the Hawaiian Islands), though there was no statistical comparison conducted between the different regions.
Read the NOAA press release here
Download the full report here