Since it first came into wide-scale industrial use in the mid 1930s, polyethylene has been chosen as the preferred material for many applications. Most of these applications came about because polyethylene is low-cost, heat resistant, acid resistant, insulant and slow to biodegrade in nature. Among these properties, the last has proven to be more of a double-edged sword as each year we continue to produce 80 metric tons and the environment breaks down far less.
Recent progress on biodegradable polyethylene has presented a partial solution, but many of the most common applications simply weren’t intended to rot under natural conditions. Most forms of tubing and cables only function effectively so long as they remain completely intact. The same can be said for most plastic car parts, electronic casings, food and drug containers, and many others.
Until recently, recycling remained our first and only effective strategy for sustainable use of “non-biodegradables”, but in 2008 it was discovered that a variety of bacteria called Sphingomonas can degrade polyethylene molecules. Since polyethylene does biodegrade very slowly in nature, a Canadian science fair student named Daniel Burd was able to isolate and eventually concentrate the specific microorganism(Sphingomonas) responsible for the breakdown. Though the right concentration does not exist in nature, high volume Sphingomonas can break down plastic in a few months instead of the 1000 years it takes now.
It should also be noted that this organism is unaltered at present, though many companies are now proficient at bioengineering bacteria for specific purposes. In the future it may be possible to breed varieties of Sphingomonas that are even more effective at breaking down polyethylene and other types of plastic.