Polluting the shores of all five continents as well as lakes and rivers around the globe, microplastics are tiny pieces of debris formed from the degradation of plastic. Scientists have expressed increasing concern over the potential threat to aquatic systems and public health by the accumulation of these microparticles. Here, we discuss what microplastics are and revisit the three R’s — reduce, reuse, and recycle — to discuss what you can do.
The Fate of Plastics
Plastic is formed by the chemical bonding of oil and natural gas. These chemically bonded chains are in the form of tiny pellets, which are melted and re-formed into the molds of familiar packaging materials such as soft drink bottles, yogurt cups, and films for meat (1). When plastic products are recycled, they are compacted, shredded, and melted back into the raw materials to make an increasing range of different end products, such as bottles and containers, furniture, or clothing.
Unfortunately, less than 10% of generated plastic is recycled (2). The unrecycled plastic waste may end up in landfills, where they produce toxic leachate. These plastics do not decompose for a thousand years. Alternatively, plastic waste from urban runoff, wastewater treatment plants, as well as rivers, harbors, and coastal tourism, can end up in earth’s oceans. Studies show high levels of plastic contamination in marine environments, mostly from terrestrial sources (3). These plastics can entangle or be ingested by animals, causing harm to their digestive systems. In addition, most plastics do not biodegrade, so they are broken down into smaller and smaller microplastics that circulate the oceans indefinitely (4).
Global estimates of the microplastic particle content in our oceans range from tens of thousands to hundreds of thousands of tons (3). Therefore, researchers have found it increasingly important to assess the environmental risks including the transfer of waterborne pollutants and the effects of microplastic uptake.
Studies have shown that microplastics can carry contaminants that can be transported to marine organisms. Due to their large surface-area-to-volume ratio and their hydrophobic surfaces, microplastic particles are susceptible to contamination by heavy metals, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and dichlorodiphenyltrichloroethane, among other contaminants (3). In addition, biofilms containing distinct potentially pathogenic microorganisms can develop on plastic in the marine system (3).
There is also evidence that microplastics and associated waterborne pollutants can enter the food chain and become enhanced to higher trophic levels. The presence of microplastics has been detected in seafood for human consumption (3).
The effects of these microplastic particles on humans are not yet clear. And while the presence and polluting nature of microplastics are known, more studies need to be done to determine the impact on marine environments as well as public health. In any case, to minimize the potential negative effects, consumers should reduce, reuse, and recycle plastic.
The 3 R’s + Recover, Redesign, Refuse, Rethink
Microparticles cannot be efficiently removed from marine ecosystems. Therefore, it is important to turn to source reduction. In addition to reduce, reuse, and recycle, “recover and redesign” and “refuse and rethink” have been suggested as additional measures for protecting the environment (3). Both the innovative (recover and redesign) and conservative (refuse and rethink) approaches are valuable for well-informed and good decision-making consumers.
Recover and redesign: one way to minimize harmful plastic waste is the production of “eco-friendly” polymers that are biodegradable or recyclable. Consumers should note that biodegradable plastic based on synthetic polymers, which are popular today, can act as a source for microparticles if released into aquatic ecosystems. Better alternatives include biobased polymers, such as starch-based or polylactic acid (PLA) plastic. However, it is also important to consider the environmental tradeoff for producing these alternatives. For instance, the environmental benefit of biopolymers is debatable, as a high amount of water, energy, and agricultural area are needed for their production. There is also the possible emission of natural gasses such as methane (3).
Refuse and rethink: Consumers can also rethink their use of plastics by making simple changes without having to worry about environmental tradeoffs or greenwashing. For example, for every consumer who substitutes plastic straws with glass or steel alternatives, 584 plastic straws are eliminated from the oceans. A steel lunch box elimates 540 plastic sandwich bags from the oceans and a reusable water bottle keeps 116 plastic bottles out of the oceans. A to-go cup eliminates 500 disposable coffee cups from the oceans and bringing your own bag to the store prevents 330 plastic bags from entering the oceans (5). These simple alternatives are surefire ways to reduce plastic waste.
Consumers concerned about the fate of their plastics, and in the environment in general, should research eco-friendly alternatives and how these alternatives were created in addition to making eco-friendly changes in their own lifestyles. WF
Published in WholeFoods Magazine April 2017