Mainly depends on the material, because the temperature resistance of plastic crispers made of different materials are different.
The most heat-resistant is polypropylene (PP) which can withstand 140°C, followed by polyethylene (PE) which can withstand 110°C, while polystyrene (PS) can only withstand heat to 90°C. Currently commercially available plastic lunch boxes for microwave ovens are mainly made of PP or PE. If the temperature exceeds their heat resistance limit, the plasticizer may be released. Therefore, long-term use of high temperature heating plastic lunch boxes to reheat food should be avoided.
If it is a disposable plastic preservation box, it is best not to use boiling water. The plasticizer in disposable plastic bowls and cups is easy to melt and release when exposed to heat, and long-term use is not good for health. Plasticizers can interfere with the human endocrine system, especially the male reproductive system. Plastic preservation box with the PET mark may precipitate plasticizers when heated above 70°C; for materials that do not meet the PET standard, the precipitation temperature point may be lower.