Fresh auricularia contains a light-sensitive substance called porphyrin. After it enters the body, it will greatly increase the sensitivity of the skin to light, so it is prone to diseases such as solar dermatitis and rash. If it is eaten too much, it will cause respiratory mucosa allergy and dyspnea. This kind of toxin is insoluble in water, so the toxicity of fresh auricularia auricula will not be reduced after washing and soaking in water. However, when auricularia auricula becomes a dry product after sun exposure, porphyrin poisons in it can decompose by themselves. Therefore, dried auricularia auricula is non-toxic.

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