For centuries, historians and archaeologists have defined periods of human history by the technologies or materials that made the greatest impact on society—like the Stone Age, Bronze Age, or Iron Age. But what age are we in now? For some researchers, according to Atlas Obscura's Cara Giamo, that question can be answered with one word: plastics.
The idea of named ages is not to be confused with geologic subdivisions of time like the Holocene or the proposed Anthropocene—a period resulting from massive human impact on the planet. This most recent geologic epoch is not yet official, but there have been many calls for its designation. A recent study argued that the Anthropocene began during the mid-20th century with the detonation of the first nuclear bombs, writes Ker Than for Smithsonian.com.
The last geologic epoch, the Holocene, is thought to encompass both the Bronze and Iron Ages. But we do not yet have a tool or material to define our current age. Scientists point to a few specifics changes that humans have wrought on the planet, including nuclear fallout and the rapid spread of materials like aluminum, concrete, and silicon as forensic proofs of humanity’s influence on Earth.
But according to archaeologist John Marston, plastic "has redefined our material culture and the artifacts we leave behind," and "will be found in stratified layers in our trash deposits," Giamo reports.
There is no place on Earth that plastics are naturally made, and the wide variety of synthetic polymers would not exist if it weren't for human action. Since the first plastic polymers were invented, about six billion tons of plastics have been made and spread around the planet, from forests to oceans. Along with the first nuclear detonations in 1945, plastics are one of the most significant changes that humans have made to the Earth’s makeup, Andrew C. Revkin reports for the New York Times.
To add to the problem, most plastics don't easily degrade, and recycling isn't an adequate solution. Not all types of plastic are easily recyclable, and there are only a few recycling plants in the United States that can process all varieties of plastic.
This means that much of the materials thrown into recycling bins can crisscross the planet several times before they are processed to produce rugs, sweaters, or other bottles, Debra Winter writes for The Atlantic. Although millions of tons of plastic are recycled every year, millions more end up in landfills or the ocean. The problem has reached the point where it's possible that in just a few decades there might be more plastic in the world's oceans than fish.
"With a presumed life span of over 500 years, it’s safe to say that every plastic bottle you have used exists somewhere on this planet, in some form or another," Winter writes.
Even if human populations worldwide change their plastic-using ways, the damage may already be done. With plastics filling landfills and washing up on coastlines around the world, the Plastic Age might soon take its place next to the Bronze Age and the Iron Age in the history of human civilization.