Top: Example of partially degraded plastic sample. Image courtesy Green Mountain Compost

In February 2022, the Biodegradable Products Institute (BPI) began offering free overs testing for compost manufacturers in the U.S. and Canada to document when compostable plastics are not breaking down. This service enables composters to submit partially degraded plastic samples for testing via a form on BPI’s website. It is designed to build a feedback loop between BPI and composters, supporting contamination mitigation by determining whether products in a composter’s overs are compostable or not.

The simple form asks for contact information, sample description and images, composting method, length of time before the sample was retrieved, and the sampling date. The samples will be tested by a BPI Approved lab and the results shared with the composter. If the items are determined to be compostable plastic, BPI will discuss field testing options with the composter including possible funding support. If the items are determined to be non-compostable, BPI will help identify sources of contamination and discuss strategies for reduction. Send questions about the program to BPI .