Many health experts recommend using glass containers to reheat food in the microwave. Some plastic containers, especially those made in years past, contain bisphenol-A, an endocrine disruptor. Studies have linked it with infertility and higher risks of breast and prostate cancers.
Check plastic containers for the recycle code numbers 3 or 7 because those may be made with BPA, according to the National Institutes of Health.
In general, recycle codes 1, 2, 4, 5 and 6 are unlikely to have BPA.
Children, whose bodies are still developing, should especially avoid BPA exposure, according to federal health officials.