Which plastic containers are best?

I talk to my mom every Monday morning because it's my day off and since she's in sales I can usually catch her at home while she's getting ready and answering calls. Like many mother-daughter relationships, our conversations can meander in numerous directions, often ending on a path I didn't expect. Today after we'd gotten the usual dating, work and rugby updates out of the way, we got talking about her weekend purge of old clothes and shoes, which led to our unanimous approval of discount stores like Marshalls, to her saying she bought glass food containers on sale the last time she was there. She finally got rid of her old Tupperware containers, some she's had for 25 years. Yikes, that's bad, but at least she knew they needed to be thrown away and were so old they could be leaching chemicals into her food. She doesn't microwave her plastic containers but she does pour hot soup into them so after many years of use, I'm sure they were not safe anymore.

She said she also wanted to buy new plastic containers since she didn't want to have only glass ones, but planned to do some research into which ones were safest and didn't contain the chemical BPA (bisphenol A). I remembered a useful article I read a year ago in National Geographic's Green Guide magazine. I bought the magazine when I moved into my apartment so I could find out which kitchen gadgets and items were the greenest. I still had the magazine so I just looked over the article again.

It recommended glass, ceramic and stainless steel, plus for lighter options that are easier to carry to work, it suggested "stainless steel or reusable storage containers made from #5 polypropylene plastic, but avoid exposing plastic to heat." The items they recommended included GladWare round #5 plastic bowls with blue lids and Ziploc "Twist 'n Loc" #5 plastic containers. I must have studies this article carefully because I have the Ziploc containers. I like them because they're the perfect size for storing leftovers and snacks for work, although a little small to pack a full meal into. But I also forgot the cautionary advice about using single-use yogurt and butter containers. They can get scratches that are hard to see, and you should store only cold food in them, not hot food (heat speeds deterioration). I've been collecting and using old yogurt, cottage cheese, butter and hummus containers since I moved in and since I've been here a year, it's probably time to rotate out the old ones with new ones.

I couldn't find that article on the Green Guide website, but I did find a handy plastic containers buying guide. So Mom, I've saved you some research time. Check it out before you hit Target (or Marshalls again) to update your kitchen.