Patients with mercury poisoning may have the following clinical symptoms: 1. symptoms of the digestive system, such as nausea, vomiting, abdominal pain, diarrhea, cramps or mucopurulent stools or even upper gastrointestinal bleeding. 2. irritation of the respiratory tract with coughing and coughing of sputum and, in severe cases, respiratory distress or even transient paroxysmal apnea. Mercury poisoning will stimulate the circulatory system and manifest, for example, chest tightness, shortness of breath, palpitations, and precordial discomfort. In severe cases, mercury poisoning may also cause acute liver and kidney failure, resulting in anuria, yellow urine or even soy sauce urine.