The information refutes criticisms questioning the materials’ biodegradability launched by the interest group Plastic Oceans International, which according to ACI relies upon a "severely flawed research article and ignores decades of peer-reviewed studies on these widely used chemistries," according to the association.
The films used in laundry and automatic dish detergent products are typically made of polyvinyl alcohol (PVA), also known as PVOH (since the OH is the alcohol group when expressed in a chemical formula). 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, says ACI.
“These films are designed to dissolve completely in the washing machine and then flow down the drain with the wash water,” comments Kathleen Stanton, ACI associate vice president, Technical & International Affairs. “ACI’s newest resource depicts the process of how detergent packets biodegrade, ultimately helping consumers understand the science behind their products.”
Material suppliers and brand owners test to the highest global standards of biodegradability using independent third-party laboratories to verify their claims, ACI notes.
More On PVOH Biodegradability
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.
The attacks made on PVOH biodegradability are based on a paper (Rolsky & Kelkar, Int. J. Environ. Res. Public Health 2021, 18(11), 6027) that ACI believes presents a flawed model and uses flawed data in that model. ACI alleges 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 organizations funding the research.
“What we can say is that what is hypothesized 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,” says ACI’s Kathleen Stanton. “One need look no further than a recently published journal article to see this issue tackled head-on, with a thorough explanation of film design, test methods and conclusive evidence of biodegradability in the wastewater treatment environment.”
That journal article is Byrne et al. “Biodegradability of Polyvinyl Alcohol Based Film Used for Liquid Detergent Capsules,” Tenside Surf. Det. 58 2021 2.