The American Cleaning Institute (ACI)

Frequently Asked Questions: Biodegradability of PVOH used in Liquid Laundry Packets (LLPs) and Other Detergent Capsule Films

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Liquid detergent packets were introduced to the North American market in 2010 and have since become an important product. They have grown in popularity because they provide a convenient way to deliver the correct dose of detergent for maximum cleaning efficiency. With increased use come more questions on what makes up the packets, especially the technology that goes into the film that encapsulates them. This page hopes to answer many of the common questions about PVOH films used in detergent packets.

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Q: What are laundry packet films made of?

A: Throughout the cleaning product industry, detergent pods and liquid detergent packets are made from water soluble films. These films are made of polyvinyl alcohol (PVOH). 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 fully dissolve and fully biodegrade in the environment after use.

Q: Are there different types of PVOH and PVA?

A: PVA stands for Polyvinyl Alcohol also known as PVOH (since the OH is the alcohol group when expressed in a chemical formula). For the purposes of this “Frequently Asked Questions” page we will refer to them as PVOH. PVOH can be manufactured in a variety of ways and with a variety of purposes. Uses range from more durable purposes such as fishing lines, papermaking, and textiles to pharmaceuticals including “artificial tears” and contact lens lubricants. Each is formulated differently and as a result will have different properties. PVOH used in detergent products such as Liquid Laundry Packets (LLPs) and dishwasher packets are specifically designed to be soluble and biodegradable in water, which may not be the case for other PVOH formulations.

Q: How is PVOH made?

A: PVOH used in detergent products is formulated using Ethylene Gas and Acetic Acid as the primary ingredients. The product is Vinyl Acetate that when processed further creates the films used to make detergent pods.

Q: Is PVOH laundry detergent film made from fossil fuels/petroleum?

A: PVOH is typically made from fossil fuels/petroleum.  The building blocks of the PVOH used in detergent film are oxygen (natural component of air), the gas ethylene (which is typically derived from petroleum or natural gas), and acetic acid (which is also typically made from petroleum or natural gas). 

Q. Can PVOH laundry detergent film be made from plants?

A: The ethylene used to create PVOH can be made from ethanol which can be sourced from corn, sugar cane, or sugar beet (bio-ethanol).  The acetic acid used to create detergent films can also be made from bio-ethanol.  Although PVOH films currently used in detergents are typically made from fossil fuels/petroleum, this will change as bio-based feedstocks become more available and cost-competitive.

Q: What are the benefits of PVOH films?

A: When used to contain detergents, PVOH films have several benefits: 

  • By encapsulating a single dose of a product, PVOH films are helping to take the guess work out of measuring.   This is especially important for users with physical disabilities. It also prevents users from wasting detergent by using too much.
  • The use of these films to make detergent packets also allows for use of more concentrated formulas. This means significantly less water in cleaning product formulas which means reduced packaging waste, less weight and fewer CO2 emissions from transporting these products. 
  • Encapsulating the highly concentrated detergent helps to make sure that users are not coming into contact with the products inside the detergent packet which could irritate skin. 

Q: What are microplastics?

A: Microplastics are microscopic solid particles made of synthetic polymer that are insoluble in water and typically resistant to biodegradation in the aquatic environment. Although our understanding of microplastics is evolving, California’s proposed definition refers to particles that are solid (i.e. not water soluble) polymeric materials that have at least two dimensions greater than 1 but less than 5,000 micrometers (µm). Such plastics may be intentionally added (such as microbeads), or result from progressive physical fragmentation of plastic objects into smaller and smaller particles that can take place in the environment. Such particles can be ingested and potentially transfer within food chains. Further, microplastics are practically impossible to remove from the environment after release. 
 

Q: How are detergent packet films different from microplastics?

A: Although PVA films have similar properties to many plastics such as flexibility, they fully dissolve in water when used and the dissolved polymers are fully biodegraded by microorganisms in water treatment facilities and the environment. Whereas microplastics are persistent in the environment and do not biodegrade.

Q: Are PVOH films biodegradable and how do we know?

A: PVA films used in detergents must meet strict standards of OECD’s test guidelines for biodegradability (301B). There is also a wealth of peer reviewed journal information that studies the biodegradability of these films. In a recent study (Byrne, et al., 2021) researchers could not find indications that film from detergent capsules is present in microplastic found in marine environments.

Q: How do PVA films biodegrade?

A: When a detergent packet enters a washing machine, the PVOH film encapsulating the product readily dissolves in the water (including cold water), allowing the highly concentrated detergent it contains to do the work of cleaning. The PVOH film will completely dissolve and at the end of the cycle, dissolved polymers go down the drain along with dirt and other detergent ingredients contained in the wash. This water will go to a wastewater treatment facility where bacteria and other microbes in the environment complete the degradation of the dissolved film. The below infographic describes the process by which biodegradation of PVOH films occurs:

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Scientific Papers: