Question from J.K.
Hi Debra,
Thank you for all the work you do figuring all this out. I’ve seen a lot of things on plastics, but one thing I’m not sure of is; how safe is it to freeze plastic containers? I make broth and like to freeze it and have always done so in glass containers, but as you know, they can crack while unthawing. I tried freezing in some of my old washed sour cream containers that are plastic, but I ended up tossing them for fear of the plastic leaching. What about making homemade popsicles in those plastic containers, or even ice cubes? If #’s 1, 2, 4, & 5 are safe, are they safe to freeze in as well?
Thanks again for your help.
God Bless!
J.K.
Debra’s Answer
I found a webpage called Freezing Plastic Water Bottles that addressed a rumor going around that one should not freeze water in plastic bottles because it releases carcinogenic dioxin. This had been attributed to Johns Hopkins University.
The author of this webpage did some research and found…
This sounds right to me because I know that heat increases outgassing and cold inhibits outgassing. So I would say the SAFEST place to use plastic is in the freezer.
Freeze the containers ahead of time (with the lids on or it may be difficult to get them on the containers) & have the food items as cold as possible before putting the food in the containers. When thawing food containers remove food from the containers as soon as possible. This will cut down on the amount of plastic molecules absorption.
Hi Debra. I have an abundance of tomatoes in the garden and I’ve always blanched to remove the skin, chopped, then frozen them in BPA-free plastic containers. Now my husband is worried that the acid in the tomatoes will leach chemicals from the plastic. I’m happy to see your comment that “the safest place to use plastic is in the freezer” but do you think he might be right about the acid? I know some people freeze in glass but I’ve read that breakage can be a problem, plus jars take up more room in the freezer. Canning is a good solution, but I don’t have time, nor the right kind of stove (glass-top). Any thoughts would be much appreciated!
My best guess is the acid wouldn’t break down polyethylene. Don’t have any evidence for it, but it’s a pretty stable plastic.
Any plastic can leach, but as i said before, plastic will leach much less in a freezer than a microwave.