Plastics #5 Polypropylene (PP) is the safest of all plastics because it’s the most heat resistant and unlikely to leach chemicals into your food or drink.
PP is also highly resistant to tears and punctures, making it great for storing items like pasta and rice that tend to be heavy enough to dent or poke holes through thinner plastic containers.
So if you’re looking for something that can withstand high temperatures without melting, breaking, or leaking harmful substances into whatever substance you’re putting inside it—like hot water—then Polypropylene should be right up your alley!