Plastic rain in protected areas of the United States

Abstract

Eleven billion metric tons of plastic are projected to accumulate in the environment by 2025. Because plastics are persistent, they fragment into pieces that are susceptible to wind entrainment. Using high-resolution spatial and temporal data, we tested whether plastics deposited in wet versus dry conditions have distinct atmospheric life histories. Further, we report on the rates and sources of deposition to remote U.S. conservation areas. We show that urban centers and resuspension from soils or water are principal sources for wet-deposited plastics. By contrast, plastics deposited under dry conditions were smaller in size, and the rates of deposition were related to indices that suggest longer-range or global transport. Deposition rates averaged 132 plastics per square meter per day, which amounts to >1000 metric tons of plastic deposition to western U.S. protected lands annually.

Reaching New Heights in Plastic Pollution—Preliminary Findings of Microplastics on Mount Everest

“…[10][11][12] However, the durability, versatility, low cost, and wide-scale use of plastic items means that plastic litter is now prevalent worldwide, even in remote areas. [13][14][15][16][17][18][19][20][21] Globally, attention has been focused on the accumulation of MP (<5 mm) and the quantity and potential impact of plastic on the marine environment. 22,23 It is estimated that 93,000-236,000 metric tons of MP is now floating on the global sea surface.…”

Scalable upcycling of thermoplastic polyolefins into vitrimers through transesterification

“…2 Although today's world seems unimaginable without the usage of plastic materials, disposed plastic is a serious concern because of environmental impact and global health threats. [3][4][5][6] It is hence imperative to chemically transform these disposed plastics into functional materials with high technological relevance. [7][8][9] The two classes of polymeric materials, thermoplastics and thermosets, are abundant in modern technology.…”

Microplastic shape, concentration and polymer type affect soil properties and plant biomass

“…Microplastics (< 5 mm) are increasingly reported in terrestrial systems, and due to slow turnover, may be gradually increasing through additions including soil amendments, plastic mulching, irrigation, flooding, atmospheric input and littering or street runoff [1][2][3][4] . As a result of their manufacturing origin, environmental degradation and intended use, these particles occur in many shapes, and cover a high physical and chemical diversity 5,6 .…”

“…The wide-spread application and the intentional or unintentional ubiquitous distribution of plastics affects even remote landscapes and agricultural sites with plastic-free management plans 12 . Other microplastic shapes, such as foams or fragments can be incorporated into the soil due to littering, street runoff 2 or wind deposition 3,13 .…”