Is it OK to use old freezer bags?

dmathis10

I'm out of the purple Lansinoh freezer bags except for some that we're stored for the last year and a half in my parents' storage building. It gets really hot in that building, so is it OK to use the bags? I didn't know if the plastic would break down in the heat?? I can go buy some today if needed but wanted to use these if I can.