1. Freshly squeezed raw milk: The hygiene of the milking environment, the cleanliness and disinfection of the containers, the health status of the milker, and the cleaning and disinfection of their hands cannot be guaranteed. Moreover, it is unknown if the freshly squeezed and sold milk is contaminated with disease. Therefore, this extremely fresh milk should absolutely not be tasted.
2. Fresh jellyfish: Fresh jellyfish contains a lot of water, has a thick body, and also contains toxins. Only after being salted and alum-pickled three times (commonly known as "three-alum") to dehydrate it three times can the toxins be fully drained away. The "three-alum" jellyfish is light red or light yellow, thin and even with a chewy texture, and no water can be squeezed out even with force. Only this type of jellyfish is edible.
3. Fresh wood ear mushrooms: Fresh wood ear mushrooms contain a photosensitive substance called porphyrin. After consumption, exposure to sunlight can cause skin pain, itching, and swelling; in severe cases, it can lead to skin necrosis. If the swelling occurs in the pharyngeal mucosa, it can cause difficulty in breathing. Dried wood ear mushrooms are a finished product that has been sun-dried. During the sun-drying process, most of the porphyrin is decomposed. When consuming, the dried mushrooms are soaked in water, and any remaining toxins will dissolve into the water, making the rehydrated dried wood ear mushrooms non-toxic.
4. Fresh pickled vegetables: Fresh pickled vegetables contain a certain amount of non-toxic nitrate. During the salt-pickling process, it is reduced into toxic nitrite. Generally, nitrite begins to increase significantly 4 hours after salting, peaks between 14-20 days, and then gradually decreases. Therefore, you should either eat the freshly pickled vegetables within 4 hours, or eat those that have been pickled for more than 30 days. Nitrite can cause hypoxia symptoms such as cyanosis, and it can also combine with secondary amines in food to form carcinogenic nitrosamines.
5. Fresh daylilies: Unprocessed fresh daylilies contain colchicine. Colchicine itself is non-toxic, but after ingestion, it is oxidized in the body into a highly toxic substance called colchicine dioxide. According to experimental calculations, as little as 1 milligram of colchicine is enough to cause nausea, vomiting, headache, and abdominal pain. A larger dose may lead to hematuria or hemafecia, and 20 milligrams can be fatal. Dried daylilies are steamed and processed, during which the colchicine is leached out, making them non-toxic.
6.桶装水：市售的桶装水，不论是蒸馏水、矿泉水、纯净水及其他净水，在装桶前大多要用臭氧作最后的消毒处理。因此，在刚灌好的桶装水里都会含有较高浓度的臭氧，对人而言臭氧是毒物，如果趁新鲜喝，无疑会把毒物一起摄入，若将这些桶装水再放1=2天，臭氧会自然消失，这时再喝就无毒之虑了。