... if some plastic containers are safer than others? Yes, for sure and you have to know the code. Inside the tiny triangle on the bottom, there's a number from 1 to 7. The safest choices for food storage are 1,2,4 and 5. Number 3 is polyvinyl chloride (PVC), 6 is polystyrene, 7 can be various plastics. Avoid them because they are toxic and potentially dangerous. Glass is always a safe bet!