Plastics are ubiquitous and do not decompose. Every piece of plastic produced since 1907 still exists. A combination of physical, biological, and sunlight exposures can degrade plastic debris, but at most to a micro or nano scale. In essence, plastics pollute land, water, and air, posing environmental and health issues for all living creatures.
Scientists are beginning to realize that this longevity dilemma might be solvable, since many species build strong, long-lasting materials that still break down into simpler compounds that can be reused by other organisms in a healthy, regenerative cycle. Plastics are made of repeating units called monomers, which can be bonded together in long, sturdy chains called polymers.
Natural organisms also produce complex polymer chains, but they can be broken down when enzymes fit into the bonds between monomers. These enzymes, found in the natural world, catalyze chemical reactions that unlock the bonds and break the chains into their component parts. With plastics, microbes and enzymes are only able to attack the surface, leaving the bonds mostly intact and out of reach of enzymes.
