River vermicelli may produce mycotoxin after a week in the refrigerator. This toxin is more likely to be produced in a humid environment. If the rice noodles become moldy, sticky, etc. after the overnight storage, it is likely that they have already produced zymotoxin.

Consumption of rice vermicelli containing zymotoxin may cause symptoms of poisoning, including nausea, vomiting and diarrhea. If the poisoning is severe, it may be life-threatening. Therefore, it is recommended to consume river noodles that have been placed in the refrigerator as soon as possible and not leave them for too long. If the river noodle has been spoiled, it is best not to consume it to avoid health problems.