A.I.S.E. research on the biodegradability of polyvinyl alcohol based film used for liquid detergent capsules has been published in Tenside Surfactants Detergents
(Volume 58, Issue 2) and is now available via open access.
This peer-reviewed publication, developed with the support of Henkel, Kuraray, McBride, Procter & Gamble, Reckitt and Unilever, reports biodegradation data for the water-soluble grades of polyvinyl alcohol (PVOH) that are most commonly used for detergent capsule films.
- Ready biodegradability screening test data on six technical (commercial) PVOH film materials were confidentially collected, anonymised, and aggregated for assessment.
- These materials represent a range of PVOH films currently on the market. These films include structural modifications and auxiliary ingredients, required to meet performance and safety requirements for this specific part of the detergents market.
- Substantial variability between the results of biodegradation studies on different films was reported. Some materials fully met the criteria for ready biodegradation. Other materials underwent biodegradation at a lower rate and did not fulfil these criteria. Nevertheless, for these materials the biodegradation process continued, and the biodegradation threshold was well exceeded subsequently as part of an enhanced test protocol.
- Modelling across all aggregated data suggests that a total extent of biodegradation of 60 % was reached after 28 days.
The ready biodegradability data on PVOH films used for detergent applications (as collected, aggregated, and reported in this paper) confirm the information in literature. Highly soluble PVOH biodegrades in an aqueous environment.
The PVOH film of detergent capsules was shown to be biodegradable in OECD screening test conditions. Despite variable biodegradation rates between studies and materials, all films were found to meet the criteria for biodegradability in these stringent studies - which offers definitive and conclusive evidence of their actual biodegradability in the environment.