What Biodegradable and Compostable Really Mean?

“There are an awful lot of product claims being made with regard to biodegradable, compostable and degradable properties. It is fairly easy to become confused on exactly what is fact and what is spin. The first step is to define what these words actually mean. There are of course definitions that can be looked up and some even have definitions written by the ASTM (American Standards for Testing Materials) which we’ll cover. But what is most important is what the average consumer thinks these terms mean. The American Chemistry Council did a study on this exact topic. They concluded that most people feel a product is biodegradable if it is able to break down naturally (on its own) in 1 year or less and leave nothing behind, or completely disappear. The FTC (Federal Trade Commission) has a very similar view on a biodegradable definition. They state that the …materials should break down in a reasonably short period of time after customary disposal.”

Facts on biodegradable products

It is very important to get the facts on products that make a biodegradable claim. What are the conditions necessary for bio-degradation to occur? There are some foamed polystyrene products on the market right now that are claiming they will biodegrade in a landfill environment. Some even offer a certificate signed by a company official, certifying the product will biodegrade in a landfill. According to the FTC however, in landfills, materials degrade very slowly, if at all. This is because modern landfills are designed, according to law, to keep out sunlight, air and moisture. This helps prevent pollutants from the garbage from getting into the air and drinking water, and slows the decomposition of the trash. In Dr. William Rathje’s book entitled “Rubbish,” he sites that “The truth is, however, that the dynamics of a modern landfill are very nearly the opposite of what most people think…Well designed and managed landfills seem to be far more apt to preserve their contents for posterity than transform them into humus or mulch. They are not vast composters: rather they are vast mummifiers.” In his book, Dr. Rathje talks about doing excavations on 15 landfills throughout North America. From those digs, they found 40 year old newspapers that were still legible, 5 year old lettuce and a 15 year old hot dog. From these studies it seems fairly clear that even organic materials take a very long time to break down in landfills let alone plastic or other items.

Facts on compostable products

Compostable product claims are another hot topic today. Once again the American Chemistry Council surveyed consumers to find out what their definition of compostable is. Their study cited that most respondents felt that compostable items can be put back into the ground to make soil, mulch or fertilizer that can be used in a garden or around the home. They also go on to state that the chief attribute of compostable materials is that the decomposition is beneficial to the earth which stands in opposition to their biodegradable beliefs that materials simply disappear completely.

The ASTM also has a definition for compostable plastic products which some municipalities have mandated as their rule and guideline that packaging must meet. The ASTM D6400 definition is quite lengthy and very specific. It covers such points as time frames for decomposition and left over materials acceptable.

You could find the entire ASTM D6400 definition on their website and read all the pages, but if you are looking for compostable products, we would recommend simply looking for products that carry the BPI logo. BPI is the Biodegradable Products Institute and is a not for profit organization that promotes the use of compostable materials and organics recovery via composting. They have a third party certification process that will verify if a manufacturer’s products meet the ASTM definition for compostability.  Products that does meet these criteria and carries the BPI logo. This means that a third party has verified that all products will turn to compost within the time frame specified in the ASTM definition. It is important to note that these products must be sent to a professionally managed composting facility in order to be composted correctly. They will not compost in a back yard compost heap. They will however completely compost at a professionally run facility. We have also sought and received verification from such a facility, that our products will do what we say they will.

Will the products biodegrade in a landfill? It is safe to say that, from the facts listed above, nothing biodegrades in a landfill in a reasonable period of time, so we will not make that claim.

Until there are tighter rules with regard to marketing claims for biodegradable and compostable products, it is really up to the consumer to do their homework. Simply because a product may be made from organic sources, one cannot assume it will biodegrade or even compost properly. Ask for third party verification proving the claims are valid. If none exist, then the consumer must make their own decision.