PVA: The Down and Dirty
We have received many messages and had several discussions in the shop about “that coating on the laundry and dish pods.” Some people have come in and told us straight up that they are terrible for water systems and we shouldn’t carry them. Others have come in asking for laundry sheets because they are convenient and don’t have that coating that pods have (bad news guys, that same coating is holding those sheets together too!) So we felt we needed to do some more research so we could give you all our down and dirty on PVA.
We need to preface the rest of this blog: We are not eco-scientists. This is our interpretation of the scientific research available to us. This write up is in no way meant to act as a research paper on its own and you need to come to your own conclusions!
Polyvinyl Alcohol (PVA or PVOH), is a promiscuous little molecule. It may be one of the most ubiquitous chemicals in our daily lives and has been touted as a biodegradable plastic alternative for the better part of a decade now. But what actually is it? Where does it come from? Where can we find this chemical in our daily lives? And most importantly, what kind of effect does this chemical have on the world around us? In this blog post I am going to try and find the answers to these questions.
What is it?
First things first, let us identify what exactly this chemical is, uhh, Houston we have a problem. PVA is more of a family of molecules rather than a specific molecule. While it has a mostly defined structure it exists in varying states of hydrolyzation and chain length. For the purpose of this blog post I will be talking about the subset that we as consumers have the most interaction with. While the various types of PVA muddies the water about what exactly is happening, the variations in the family of molecules used in consumer products such as laundry sheets and pods, dishwasher pods, etc. does not seem to affect the routes of degradation that have been reported.
How is it used?
So where exactly is PVA used? Well, it might be easier to see where it is not used! PVA is expected to be a billion dollar trade chemical in the coming years with most of the consumer end products being bought for the food packaging industry; roughly 31% of the total demand reported. But it can also be seen in electronics use, further chemical synthesis, coatings, printing, paper manufacture, cosmetics, construction, this list goes on. If you were to pick up a product in your house there is a good chance that PVA is either in it or aides in the manufacturing to make it. Terrifying. Or is it?
Where does it come from?
As for where this chemical comes from: PVA is a synthetic resin that does not naturally occur which is not exactly out of the normal in 2022. Importantly PVA is listed on the EPA’s website as meeting all of the criteria for their “Safer Choice” program, with full confidence that “The chemical has been verified to be of low concern based on experimental and modeled data” - Chemview.epa.gov. While it is certainly reassuring that we are not dumping toxic waste into the water table every time we wash our clothes, I do feel that it is worth exploring why the EPA has come to this conclusion, not only about the consumer products we use everyday but also the manufacturing grade products that we can find all around us.
So what, is it okay to use?!
So PVA is biodegradable, at least that is what the EPA has concluded. But what about independent review? If you do a quick Google search, one of the first “studies” that comes up is one funded by Blueland (a company that manufactures and sells tablet cleaning products) - which inherently means you should question the validity of the study. It makes quite a few assertions (mostly based on other plastics) that it believes that PVA is likely bad for the environment but then ends with “Very little research exists that aims to monitor the biodegradability of PVA in the natural environment. This presents a challenge in determining its role or impact as a pollutant. Research into truly eco-friendly substitutes for PVA is warranted and should be further explored.” Clearly that would help the company funding the study! It also states “Literature review data, when incorporated into our model, resulted in ~61% of PVA ending up in the environment via the sludge route.” I did some further looking into this sludge state and found some more compelling research.
In my literature search it would seem that many people agree that PVA is biodegradable, mostly by microorganisms in the family of Pseudomonas spp. and a few others. Some papers concluded that the degradation of PVA is largely dependent on where it ends up, i.e. the bacteria in the area is what determines if the molecule is able to be degraded or not. However, it has been demonstrated that bacteria are able to acclimate to the chemical quickly and begin breaking it down on a short enough time scale to not be concerning. So the water goes down the drain to the waste treatment plant, filled to the brim with bacteria, which have been shown to be well acclimated to PVA. PVA is 100% biodegraded in the sludge found in wastewater treatment plants on a timeline of days to less than a week for full degradation. But what about unacclimated bacteria? They tested that too, and data would suggest that after a few days of adaptation, 100% degradation can be achieved in approximately 15 days. Both of these conditions would meet biodegradable standards and thus we have proof the PVA is biodegradable.
We would never tell you how to live your life. You have to do you and do what you think is best for you and yours. That said, our research leads us to believe that PVA is likely not harming the environment and bacteria seem to enjoy breaking it down. Additionally, it is used in EVERYTHING from your food packaging to your electronics which makes it nearly impossible to avoid. At least you can rest fairly assured that the PVA used in laundry and dish products, that goes through the water system, gets enjoyed by bacteria!
Blueland study: https://www.mdpi.com/1660-4601/18/11/6027/htm