Biodegradation is the decomposition of organic (living or once living) materials by micro-organisms as part of nature’s recycling system of growth and decay. Substances that are biodegradable break down naturally into simpler materials, instead of persisting in the environment.

There is a lot of confusion surrounding the importance of the biodegradability of solid materials. In Australia, it’s a commonly held myth that it’s okay to send biodegradable materials to landfill as they will eventually break down. However, the biodegradation of organic materials in landfill produces a greater proportion of methane gas and a lesser proportion of carbon dioxide, compared with breaking down in a well-aerated compost bin in a backyard.

Methane has over 20 times the global warming potential of carbon dioxide, meaning that the thoughtless dumping of large amounts of biodegradable material in landfill has a significant greenhouse impact.

Biodegradability is one consideration in material choices, but is not the ultimate solution to our waste problems. It does not make the materials available again in a similar form for further manufacture. Biodegradability does NOT give you the green light to use disposable convenience products. That is why environmentalists have favoured the use of reusable bags for supermarket shopping over moving to biodegradable single-use checkout bags. Reusable products are generally preferable to single-use products that will be disposed of in landfill.