Can plastic lunch boxes still be used after being stored for 6 years

Whether plastic lunch boxes can be used after being stored for 6 years depends on the material and storage status. If there is no obvious aging, deformation, or odor, they can usually continue to be used. Plastic products may release harmful substances due to material degradation, high temperature, or chemical corrosion. It is recommended to prioritize food grade PP materials and undamaged lunch boxes. The safety of using plastic lunch boxes after long-term storage mainly depends on the type of material used. Food grade polypropylene material is resistant to high temperatures and has good stability. If stored in a dark and dry environment, it does not come into contact with oil or strong acid or alkali substances. The structure is intact without cracks and usually still meets the usage standards. Before use, thoroughly clean with warm water and neutral detergent to observe for scratches or discoloration, which may increase the risk of microplastic precipitation. For containers that have been used to hold stained or highly acidic foods, it is even more important to carefully evaluate their safety. Some inferior plastics or non food contact grade materials are prone to oxidation and decomposition after long-term storage, especially lunch boxes that have been repeatedly heated or exposed to ultraviolet radiation, which may release harmful ingredients such as plasticizers. If the surface of the lunch box becomes sticky, brittle, or has an abnormal odor, it indicates that the polymer chain has broken and should be immediately stopped from use. Colored plastic products have a higher risk of pigment migration, and it is not recommended to continue exposure to high-temperature foods.

When using plastic tableware in daily life, avoid microwave heating of non high temperature resistant labeled products, and store away from heat sources and chemical solvents. Regularly replacing plastic lunch boxes that have been in use for over two years and choosing glass or stainless steel materials as alternatives is more beneficial for health. If there are doubts about the safety of old lunch boxes, boiling tests can be conducted to observe whether they have deformed, but the safest way is to replace the container with a new one to ensure food safety.