The End of Single Use Plastics in the Kitchen
A few years ago I was sitting in a Master Water Steward class learning how to be a better steward of the water resources in my community. The topic of plastic sandwich bags and whether washing and reusing them was more sustainable than throwing them away came up. On the one hand, you use quite a bit of water to clean them, but on the other you are wasting a lot of plastic every year that contributes to our growing landfill problem. No one had a good answer and we moved on to another topic. I forgot all about the question until I recently purchased a pack of durable reusable plastic bags. When we had the discussion years ago these types of reusable bags were not readily available, so I was curious how a long lasting bag instead of washing a regular Ziplock that would eventually wear out would change which was better environmentally.
Water in Production
To question was simple, is it better to use water to wash out the reusable bag or buy single use bags and throw them away after each use. I began with an understanding of all the ways water is used in the life cycle of a bag. There's the visible water needed to wash the reusable bag and there is virtual water which is the water used to make a plastic bag. Nearly all products have a virtual water footprint. Your smartphone for example took almost 3,200 gallons of water to make which is a little shocking when you consider today's smart phones barely make it to the end of the two year contract before they start glitching and losing battery life. Our cars take between 13,700 and 21,900 gallons of water to make. Worst may just be the amount of water required to produce a plastic water bottle. It takes about double the amount of water contained in the actual bottle itself.
Water in Reusing
One pound of plastic requires 22 gallons of water to make. When considering one quart sized single use bag is about 0.2 ounces means that it takes roughly 11.68 cups of water to make one Ziploc bag. It only took me 6 cups of water to wash it out to reuse again (I'm the type that doesn't let the water run when I'm scrubbing dishes). My reusable bag weighs more than a single use bag since its meant to be durable, so it actually took just under 4 gallons of water to make. I calculated it would take about 11 uses of my reusable bag to overcome the initial difference in water used to make the bag versus continually throwing away the plastic bags and buying more. I have already reached 11 uses and therefore each time I reuse the bag now I save just under 6 cups of water (not being used to make the bag) and add nothing to the landfill.
More detailed studies exist that go through the full life-cycle cost of a sandwich bag but knowing less waste is in the landfill and more water is conserved is enough to sell me on my reusable sandwich bags. With families using on average 500 sandwich bags each year that equates to roughly 58,164,130 bags in the landfill or 11,632,826 pounds of wasted plastic. The virtual water waste is equal to 255,922,172 gallons of water (or 387 Olympic swimming pools of water) used to make the bags.
The Solution
Since February I have been using these reusable sandwich bags which come in a variety of sizes. They have worked great for leftovers, snacks to take to work, and storing my vegetables. They also save money in the long run since I will never need to spend $6 on a box of plastic bags at the grocery store every few weeks anymore.
I also stopped using plastic wrap which also has a negative impact on our water use. Since its more difficult to calculate out the impact (plastic use varies by whatever you are covering) I decided to trust that a reusable option is going to be better in the long run than trashing the plastic wrap and buying more. I have been using these beeswax wraps since February as well and love them more than plastic wrap. They mold over dishes and actually adhere to the dish much better than plastic wrap which never seemed to stick. Similar to the bags, the upfront cost was quickly regained after a few reuses compared to buying several boxes of plastic wrap at $6 a box. And they are really cute designs which is an added bonus.
These are two relatively small changes that did not take much to get used to, yet they will have a significant impact on waste and water use over my lifetime. My next step will be to figure out how to substitute tinfoil in my husbands grilling/smoking process.
