1. Biodegradation occurs when materials are broken down by bacteria, fungi, or other biological means. Composting requires biodegradation in order for organic matter to decompose and be turned into fertilizer and soil conditioners. Biodegradation doesn’t necessarily require composting, but composting requires biodegradation.
2. Degradation and/or fragmentation are not the same as biodegradation. In most cases, degradation means that the structural integrity of a product is compromised (often due to chemical or mechanical actions). It is possible for a product to degrade or fragment without actually biodegrading. Note that fragmentation can sometimes help increase the rate of biodegradation, but simple degradation and/or fragmentation do
not guarantee that a product will biodegrade.
If the intention is to produce compost or reduce the presence of solids, the most desirable results for plastic packaging and products is that they biodegrade. Biodegradation of a plastic is confirmed through testing by measuring the actual amount of carbon elements that are converted into carbon dioxide and methane gases during the test period.
3. There are two types of biodegradation:
• Anaerobic digestion occurs when microorganisms break down material in the absence of oxygen. It is used in industrial processes to manage waste or to produce fuels, and also causes the fermentation need to produce food and drink products.) Anaerobic digestion occurs naturally in some soils and in lakes and oceans. Methane (CH4) and carbon dioxide
(CO2), both greenhouse gases, are two end products of this process.
• Aerobic digestion occurs when material is broken down in the presence of oxygen. It has traditionally been used as a sewage treatment process, but recent technology allows for the aerobic treatment of food, cardboard, and plant waste in industrial compost facilities. Water
vapor, carbon dioxide, and ammonia (NH4) are end products of this process.