Yes, You Can Wash and Reuse Ziploc Bags—Sometimes
From K-cups to bubble wrap, many products billed as being disposable are actually reusable. But when it comes to Ziploc bags and other plastic baggies with resealable openings, their longevity beyond your desk lunch isn't always clear. According to The Takeout, you can save money and reduce waste by washing and reusing plastic Ziplocs in some cases, but in others, using the plastic bag more than once can get you sick.
When deciding whether or not to keep a used Ziploc in your kitchen, think about what you used it for in the first place. If it was used to store or marinade raw meat, eggs, or seafood, you should toss it in the trash. These products can contain dangerous pathogens in their uncooked state, and no matter how well you scrub the bag afterwards, there's no way to be sure you sanitized the bag completely.
If you filled the bag with products that are safe to eat and touch as they are—like baked goods, clean produce, sandwiches, etc.—it should be safe to use a second time. This rule doesn't apply to bags that have holes, tears, or look worn out in general.
For used bags that held safe foods and are still in good shape, Ziploc recommends hand-washing them and drying them thoroughly. Once they're clean, they're about as safe to eat out of as a reused Tupperware container. If you want to reuse the bag multiple times, just be aware that most sealable bags are made to be disposed of eventually, and it will likely develop wear and tear.
Another eco-friendly way to store food is to avoid lightweight plastic products altogether. Here are some reusable products that make packing lunch easy.
[h/t The Takeout]