Biodegradability
of solvents and coalescents

Classifications of biodegradability

Readily biodegradable is a term used for substances that meet the very stringent testing criteria of a readily biodegradability test demonstrating ultimate biodegradation in a specified time period. Substances that are readily biodegradable are expected to rapidly degrade in wastewater treatment plants or in the environment. Being readily biodegradable is one of the key criteria for demonstrating a lack of persistence in persistent, bioaccumulative and toxic (PBT) assessments, hazard classifications, or green chemistry certifications.

Inherently biodegradable is a term for substances that can be biodegraded under specific conditions. The inherent biodegradability test is not as stringent as a readily biodegradability study. It uses a greater amount of microorganism inoculum and doesn’t have as strict a time component. It is often used when a substance is not able to pass a readily biodegradable test but will demonstrate whether or not the substance will eventually biodegrade.

Predicted to be readily biodegradable indicates that the substance has not been tested for biodegradation but is predicted to be readily biodegradable based on quantitative structure-activity relationship (QSAR) modeling.

Glossary of biodegradation terms per REACH (Table R. 7.9-1)