Does PVOH Film Really Biodegrade? What ISO 14852 and ASTM D6691 Tests Show

Why "it dissolves" is not proof

A film that disappears in a glass of water has only dissolved. The polymer is still there, now as a solution. Biodegradation is the next step, when microorganisms consume that solution and turn the polymer into carbon dioxide, water and biomass. Buyers should ask for proof of the second step, measured by a recognised standard, with the number of days.

Our rule for every degradation claim is simple: we write "passed [standard] in N days", we name the lab, and we do not use percentages or vague words such as "eco" on their own.

What ISO 14852 measures

ISO 14852 determines the ultimate aerobic biodegradability of plastic materials in an aqueous medium, by measuring the carbon dioxide evolved. The test material is exposed in a synthetic medium, under standardised laboratory conditions, to an inoculum from activated sludge under aerobic conditions. The standard explicitly applies to water-soluble polymers (ISO 14852:2021).

Because the inoculum comes from activated sludge, the test is a good reference for what happens when a PVOH film dissolves in a washing machine and the solution goes to a wastewater treatment plant with aerobic biological treatment.

AquaFlex result: passed ISO 14852 in 32 days in fresh water (OK biodegradable WATER technical report, ARCHA S.r.l.).

What ASTM D6691 measures

ASTM D6691 determines the degree and rate of aerobic biodegradation of plastic materials exposed to marine microorganisms, either a defined consortium of at least ten marine microorganisms or the indigenous population of natural seawater, under controlled laboratory conditions. Biodegradation is measured as the carbon dioxide produced (ASTM D6691).

ASTM itself notes that results describe the conditions of the test and should not be extrapolated beyond its duration. That is why we state the environment and the days, and we do not promise what happens in every sea.

AquaFlex result: passed ASTM D6691 in 43 days in natural seawater (OK biodegradable MARINE technical report 22410332, ARCHA S.r.l.). The same programme included an OECD 202 ecotoxicity test, which AquaFlex passed.

Industrial compost: ISO 14855-1 and EN 13432

EN 13432 is the European standard for packaging recoverable through composting. It requires biodegradation, disintegration, no negative effect on the composting process and good compost quality; disintegration must reach 90 percent within 12 weeks in a pilot test (European Bioplastics).

AquaFlex result: passed ISO 14855-1 in 125 days in industrial composting. ARCHA S.r.l. report 22311632 (Feb 29, 2024) covered the full EN 13432 checklist: chemical characterisation, heavy metals and fluorine, biodegradation, disintegration to ISO 16929 on 30 µm and 61 µm film, final compost quality, and a plant toxicity test on barley and cress. Every item was judged compliant. We do not claim home compostability, because no home compost test has been run.

All results at a glance

These are lab test reports from ARCHA S.r.l., an independent laboratory in Pisa, Italy, run under ISO and ASTM standards. They are strong, valid references that most competitors on this material technology do not reach. Ask us for the reports, or see the AquaFlex film page and the lab test reports page.

What independent research says about PVOH in wastewater

PVOH from detergent films has been studied widely. A 2024 study in Integrated Environmental Assessment and Management ran an OECD 303A wastewater treatment plant simulation on a non-modified detergent-film PVOH and observed high levels of removal due to biodegradation (IEAM, 2024). The American Cleaning Institute states that detergent-grade PVA is designed to dissolve and biodegrade in wastewater treatment (ACI).

Results always depend on the grade. Other researchers have reported residues from some commercial detergent pods (Chemistry & Chemical Technology, 2023). That is exactly why a buyer should ask for test reports on the film being bought, not on PVOH in general.

What these tests do not say

Lab tests run under controlled conditions: a set temperature, a known inoculum and a measured amount of material. They show that a material can be fully converted by microorganisms in those conditions and how quickly. They do not mean that packaging may be littered, and real environments vary in temperature, oxygen and microbial life. That is why we describe results as "passed [standard] in N days" and keep the standard, the lab and the report next to every number.

Results also belong to the material that was tested. The ARCHA tests cover AquaFlex film; for a laminate such as AquaFlex paper, only the film or coating was tested, not the full laminate. Ask the same question of any supplier: which product, which thickness, which report?

The three reports in detail

Thickness is part of the result. A report covers the film that was tested, so if you plan a much thicker bag, ask how your thickness relates to the tested samples before you write any claim on pack.

What OECD 202 adds

Biodegradation tests show that the polymer is consumed. Ecotoxicity tests ask a second question: is the water harmful to aquatic life? OECD Test No. 202 exposes young daphnids, small freshwater crustaceans less than 24 hours old, to the test substance at a range of concentrations for 48 hours, and records how many can no longer swim at 24 and 48 hours (OECD). AquaFlex passed OECD 202 within the ASTM D6691 seawater programme.

Worked example: from washing machine to treatment plant

• In use. A hospital puts soiled linen in a hot water B-HWS laundry bag and loads the closed bag into the machine.
• Dissolving. The bag dissolves in the wash cycle; nobody opens it by hand.
• Wastewater. The PVOH solution leaves with the wash water toward wastewater treatment with aerobic biological treatment.
• Evidence. ISO 14852 uses an inoculum from activated sludge, which is why it is the closest lab reference for this route; AquaFlex passed it in 32 days.

A garment bag follows a different route, because it does not dissolve in use. For that case, tell end users how to dispose of it and base the wording on the reports above.

Which claim needs which evidence

How to read a supplier's claim

• Is the standard named (ISO 14852, ASTM D6691, ISO 14855-1)?
• Is the result given in days, with the environment?
• Is the lab independent, and is the report number given?
• Does the test cover the film you are buying, or only a resin or another product?
• Is home composting claimed without a home compost test?

For the full buying process, see How to source PVOH film. For background on the material, start with What is modified PVOH?.