A recent study by Plastic Oceans International and Arizona State University, published in the International Journal of Environmental Research and Public Health, claims that detergent pods are contributing to the plastic pollution problem, leaking large amounts of untreated PVA - polyvinyl alcohol - into the environment, and possibly into the human food chain. Based on an extensive literature review, the authors concluded that as much as 75% of PVA from detergent pods goes untreated in the US.
“Because of water solubility, PVA turns into a solution, then goes down the drain, where the chances of it fully biodegrading are very low,” said Charlie Rolsky, one of the article’s co-authors who serves as the Director of Science for Plastic Oceans International. “The pods can easily pass through wastewater treatment plants and travel to ecosystems beyond.”
Not so, says the American Cleaning Institute. Calling the research article ‘severely flawed’, it has published new, online resources to provide ‘science-based information’ about the technology behind the water-soluble films used to package pre-measured doses of detergent.
Parrying the criticisms of Plastics Oceans International, the institute noted that a great amount of research has gone into these films to ensure they are safe to use in the home, along with the ingredients they encapsulate, and that they meet rigorous standards to ensure they fully dissolve and biodegrade after use. It added the riposte that 'any subject matter expert would see this paper as being designed not to test a hypothesis, but to arrive at a predetermined conclusion aligned with the opinions of the organisations funding the research'.
“These films are designed to dissolve completely in the washing machine and then flow down the drain with the wash water,” said Kathleen Stanton, ACI Associate Vice President, Technical & International Affairs.
Material suppliers and brand owners test to the highest global standards of biodegradability using independent third-party laboratories to verify their claims.
In an analysis of the paper, the ACI briefly summarises its inaccuracies and shortcomings. To counter misinformation about the biodegradability of PVOH, ACI worked with scientists and technical experts at several of its member companies to consolidate real-world research and data, now available on ACI’s website.
“What we can say is that what is hypothesised in the paper wildly contradicts more than 30 years of published science and ignores the rigorous product design and test methods used by the cleaning products industry to confirm the ready biodegradability of detergent film polymers,” said ACI’s Kathleen Stanton.
For further reading, she pointed to an article by Byrne et al, entitled ‘Biodegradability of Polyvinyl Alcohol Based Film Used for Liquid Detergent Capsules’ which appeared last year in the journal 'Tenside Surfactants Detergents'.