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How Biodegradation Additives Work


The Biodegradation Additives Debate
You’ll see more and more degradable products appearing on the market, often with markings that indicate biodegradable properties.
You’ll see more and more degradable products appearing on the market, often with markings that indicate biodegradable properties.
Courtesy Bio-Tech

Plastics are everywhere. Plastics are big, big business. So, many organizations have a lot at stake when it comes to the regulation and politics of biodegradability. A lot of people argue the details about whether various plastics really rot. And if they do, how long it takes and what sort of byproducts they leave behind.

To define biodegradability, governments and companies turn to the American Society for Testing and Materials (ASTM). ASTM develops voluntary consensus standards for all sorts of products and services, both in the United States and internationally.

The ASTM standards for biodegradability are still evolving, and although it's not yet a standard, many organizations adhere to the ASTM D-5511-11 testing method. This test helps companies determine the biodegradability of plastics in an anaerobic environment like a landfill.

Because decomposition tests take time and trial-and-error, there's plenty of room for disagreement as to what the test results mean. Companies that make various types of biodegradable plastics, oxo-degradable plastics, and compostable bioplastics push each other for proof that their approach is superior.

Charles Lancelot, executive director of the Plastics Environmental Council, has been working with plastics for 40 years. He says that politics and PR games, especially in California, have misled the public about the differences between these plastics.

He points to PLA-based bioplastics, which are made from corn starch, as one example. Corn and agriculture lobby groups want PLA in more products because doing so will increase the demand -- and eventually the price -- for corn.

But Lancelot says that PLA products just don't degrade unless they're composted professionally. And from an environmental point of view, that makes them less desirable than plastics that truly biodegrade in landfills and ditches. He also highlights a drawback of oxobiodegradable plastics; they need UV light and oxygen in order to degrade, and those variables are in short supply in a landfill.

In order to calm controversy and build exacting standards for biodegradation, Georgia Tech and North Carolina State Universities are performing landfill simulations and will submit their findings and recommendations to the U.S. government. New standards will be publicized by the media and likely will affect public opinion on various types of degradable plastics for years to come.

Public pressure, as well as more efficient means of making biodegradable plastics, could well accelerate the acceptance and use of these additives in many products. In the end, that could mean more environmentally friendly plastics, ones that disappear completely -- instead of lasting for millennia as a hallmark of a civilization that knew how to make wonderfully durable products yet couldn't find a way to properly dispose of them.