There are two concepts of preserved egg poisoning. The first is bacterial poisoning and the other is lead poisoning.

Bacterial poisoning means that preserved eggs have been contaminated with Salmonella before consumption, and the bacteria multiply in the preserved eggs. After humans consume it, symptoms such as nausea, vomiting, abdominal pain, and diarrhea will occur. Although vinegar has a certain sterilizing effect, it is impossible to kill all bacteria. People who eat spoiled preserved eggs with vinegar will still be infected. Bacterial preserved egg poisoning is the most common preserved egg poisoning, and this is what we usually refer to as preserved egg poisoning. Therefore, when buying preserved eggs, it is best to buy ones with intact shells and no cracks. If you find any abnormality in the preserved eggs after cutting them, do not eat them. After all, the medicine is much more expensive than preserved eggs.

Lead poisoning is due to the traditional method of pickling preserved eggs using pickling materials containing heavy metals such as lead and copper, resulting in high lead content in preserved eggs. Long-term consumption will cause lead to accumulate in the body, reaching a certain level. Excessive amounts will produce symptoms of poisoning. This is a long-term process, and you will not be poisoned by eating preserved eggs in a short period of time. Therefore, when buying preserved eggs, it is best to buy lead-free preserved eggs. This kind of poisoning has nothing to do with whether vinegar is used or not.