ASTM D5338 – Biodegradation Test – Composting

ASTM D5338 is a standard biodegradation test that measures aerobic biodegradation of plastic materials under controlled composting conditions.

Situ Biosciences has currently suspended testing according to the ASTM D5338 due to complications associated with the COVID-19 mandatory quarantine.

This ASTM biodegradation test method is an aerobic biodegradation test that introduces material to a mixed bacterial and fungal environmental inoculum and uses respirometry to measure biodegradation.

Standard testing for ASTM D5338 is a minimum of 90 days in an aerobic and controlled composting environment.

As the test samples are exposed to an inoculum derived from a municipal waste stream, the material will (ideally) biodegrade in a representative environment as commonly found in standard compost facilities.

ASTM D5338 is a core component of the ASTM D6400 Compostability Test Method, which is recognized by many Municipalities, Regulatory agencies, and The Federal Trade Commission as a requirement for making biodegradability claims about a product or material.

Given the specific conditions required for aerobic biodegradation and the wide range of composting facilities, ASTM D5338 is used primarily for materials that have yet to be introduced into the waste stream.  Because the ASTM D5338 is the core component for the testing of the composting portion of the ASTM D6400, the limitation to the types of samples tested and material challenges are the same.

Customers are requesting ASTM D5338 for paper, paperboard, corrugated, plastics and polymeric materials, and it is often used for food and beverage containers in addition to ingredients and components of larger formulations.

For more information about aerobic biodegradation, contact our biodegradation lab at 847-483-9950 or