Degradability and composting seem like nature's way to make things "disappear" after their useful life, a seemingly simple solution to the complex problem of managing and disposing of solid waste. But often what may appear to be a simple solution is not the answer to a complex problem, particularly when dealing with solid waste issues. As part of Plastics Foodservice Packaging Group's continuing effort to foster a better understanding of polystyrene packaging and provide factual information about packaging, solid waste management, recycling, and source reduction issues, here are several facts about packaging, degradability, and composting.
Designing packaging materials to degrade, either through biodegradation (the break down and consumption of materials by naturally-occurring microorganisms) or photodegradation (the break down of materials from sunlight), is not currently a viable option to manage solid waste in the U.S., but is a supplementary one at best.
Degradability of Materials and Municipal Solid Waste (MSW) Landfills
While degradable materials may not be intended to end up in landfills or incinerators, the reality is that the majority of MSW in the U.S., including degradables, is disposed of in landfills (57 percent) or is incinerated (15 percent), places where degradation does not occur.(1)
A very common misconception is that materials biodegrade in a reasonable timeframe in today's landfills. It is often mistakenly thought that landfills are vast composters, when in reality, they are vast mummifiers of waste. Very little of the waste discarded in today's modern, highly engineered landfills, including paper, plastic, and even food, biodegrades -- and it's not supposed to. Biodegradation of materials has hidden costs, the creation of potentially harmful liquid and gaseous by-products that could contaminate groundwater and air, including carbon dioxide and methane, heat-trapping greenhouse gasses that international efforts currently aim to reduce. Because of this, today's landfills are designed to minimize contact with air and water required for biodegradation to occur, thereby practically eliminating the biodegradation of waste.(2)
MSW Composting and Home (Back Yard) Composting
MSW composting is not currently a commonplace method of managing MSW in the U.S. Those programs that do exist generally accept only organic materials (leaves, grass, yard trimmings). Composting opportunities for other materials, including packaging materials, are very rare. As of December 2002, there was a total of only 15 MSW composting projects currently operating in the U.S., generally in rural areas, and interest in the development of new facilities is low.(3) There are three primary reasons why mixed waste composting is not viable as a large-scale waste management option:
- In most cases, the economics of this option do not compare favorably to landfilling or incineration;
- There are very limited viable, long-term markets for the compost material produced. Generally, it is used for minor public works applications and landfill cover; and
- There are often severe odor problems associated with this technology that make siting mixed composting facilities very difficult.
Home composting is also not a widespread method of MSW management in the U.S. Used primarily for home-generated yard debris and food scraps, home composting is done by only a very small percentage of all U.S. households.
Degradability and Litter
A widely held misconception is that litter is a problem caused by specific materials themselves rather than aberrant consumer behavior. The reality is that some people improperly dispose of materials by littering. Littering is a matter of behavior; people who discard materials into the environment usually do so because they don't think or don't care. Attributing the litter issue to one particular packaging material does not solve the problem because another type of packaging will take its place as litter unless behavior changes.
Degradation of materials is not a practical or functional technique for alleviating litter problems. In fact, there is a concern in some circles that degradable packaging may lead to an increase in the amount of litter by giving consumers a sense of lessened responsibility for properly disposing of waste. Consumer education and awareness is the practical solution to effectively address litter concerns.
Conclusion
Based on the realities of solid waste management in the U.S., it is currently not in the interest of the consuming public, nor consistent with sound environmental practices, for degradability of materials to be promoted as a viable remedy for dealing with municipal solid waste without the wide availability of composting facilities to accept these kinds of materials.
(1) "Municipal Solid Waste in the United States 1999 Facts and Figures," prepared for the United States Environmental Protection Agency, by Franklin Associates, July 2001.
(2) "Rubbish! The Archaeology of Garbage," William Rathje and Cullen Murphy, 1989.
(3) "BioCycle: Journal of Composting and Recycling," January, 2003
