There was a book released called The World Without Us, about how the Earth would adapt if humans were to vanish overnight. (A review in The Age.) A chapter excerpt shows the alarming impact that the huge amount of plastics humans manufacture have upon the environment. A bit of trivia I came across is that a plastic container might not decompose for as long as 50 000 years! Imagine the millions of tonnes of plastic items that end up in the world’s landfills and oceans, and the long-term implications are alarming, as the book extract points out.
What did this mean for the ocean, the ecosystem, the future? All this plastic had appeared in barely more than 50 years. Would its chemical constituents or additives – for instance, colorants such as metallic copper – concentrate as they ascended the food chain, and alter evolution? Would it last long enough to enter the fossil record? Would geologists millions of years hence find Barbie doll parts embedded in conglomerates formed in seabed depositions? Would they be intact enough to be pieced together like dinosaur bones? Or would they decompose first, expelling hydrocarbons that would seep out of a vast plastic Neptune’s graveyard for eons to come, leaving fossilized imprints of Barbie and Ken hardened in stone for eons beyond?
[…]
“Plastic is still plastic. The material still remains a polymer. Polyethylene is not biodegraded in any practical time scale. There is no mechanism in the marine environment to biodegrade that long a molecule.” Even if photodegradable nets helped marine mammals live, he concluded, their powdery residue remains in the sea, where the filter feeders will find it.
“Except for a small amount that’s been incinerated,” says Tony Andrady the oracle, “every bit of plastic manufactured in the world for the last 50 years or so still remains. It’s somewhere in the environment.”
That half-century’s total production now surpasses 1 billion tons. It includes hundreds of different plastics, with untold permutations involving added plasticizers, opacifiers, colors, fillers, strengtheners, and light stabilizers. The longevity of each can vary enormously. Thus far, none has disappeared. Researchers have attempted to find out how long it will take polyethylene to biodegrade by incubating a sample in a live bacteria culture. A year later, less than 1 percent was gone.
“The Fate of the Ocean”, Mother Jones, March 2006. This was linked from a Wikipedia page about the ocean; it’s an alarming read about how human activity is damaging the world’s oceans on which all life depends, and the damage might be irreversible. Reading all this makes me feverently wish that someone would genetically-engineer a virus to sterilize most of humanity.
