Biodegradability is defined as the ability of a substance to be digested or consumed by naturally occurring microorganisms present in water, air and soil systems. Complete biodegradability is the conversion of a substance to carbon dioxide and water.
How is biodegradability measured?
There are several standard test methods used to measure biodegradability. The method generally accepted in Europe is the Organization of European Cooperative Development (OECD) 301A-F test. This test is accepted by product developers and consumers as a “measuring stick” to help the user understand a product’s environmental impact. ASTM D7373 is also gaining acceptance as evidenced by EPA’s inclusion into the 2013 VGP guidelines.
Acceptable or passing levels for these tests are as follows:
|Biodegradability, %||ASTM D7373||> 60%|
|Biodegradability, % in 28 days||OECD 301A-F||≥ 60%|
Are all biodegradable products the same?
Beware of greenwashing! While many products claim to be biodegradable, the question of how quickly and easily they degrade is critical to how environmentally friendly they can be considered and how they are treated by law.
There are two widely used designations for biodegradability: Inherently biodegradable and readily biodegradable. Simply saying something is biodegradable still means it can persist in the environment for years, continuing to cause substantial damage, and often require long-term remediation—for example, petroleum-based products. Inherent biodegradation is defined as degrading > 20 percent to < 60 percent within 28 days. Readily biodegradable materials, on the other hand, degrade by 60 percent or more within 28 days or less. For those products on the quicker range of degradation, like those of RSC Bio Solutions, this means that major environmental damage can likely be avoided.
What differentiates Inherently Biodegradable from Readily Biodegradable?
Inherently biodegradable is defined as > 20% but < 60% biodegradability as measured by OECD 301A-F testing. This characteristic is defined by the original composition of the product. Readily biodegradable is defined as the ability of a product to biodegrade quickly and completely (≥ 60% by OECD 301A-F/ASTM D7373 testing) within 28 days. Readily biodegradable products are environmentally preferable.
Why would I want to use readily biodegradable lubricants?
Biodegradable oil can be used in any equipment operating in sensitive environments. Biodegradable oils have been designed for equipment that can come in direct contact with air, soil, or water systems and pose limited risk to aquatic life because these products are minimally toxic and not bioaccumulative.