I. Diagnosis: Unlike the traditional meaning of poisoning, lead poisoning in children does not mean poisoning in the clinical sense, but indicates that the lead load in the body is at a dangerous level that is detrimental to the health of children. Most children with lead poisoning are in subclinical state, therefore, the diagnosis of childhood lead poisoning does not depend on the presence or absence of corresponding clinical symptoms and signs, but mainly on the status of lead load in the body. (a) Measurement of lead content in tissues: 1. Blood lead: it can most directly reflect the lead load condition and is the main means to evaluate the lead load in the body, and the indicator recognized by the international health community to accurately measure whether children are lead poisoned is blood lead concentration. The half-life of lead is about 30 days, and blood lead can only reflect the recent lead exposure, but cannot indicate the exposure status one month ago. However, in a stable, low-level lead exposure state, blood lead level can reflect lead exposure and lead load status in the body. 2.Bone lead: It is the most objective indicator of lead load in the body, but has no clinical application value. 3.Dental lead: Once lead is deposited in teeth, it will no longer be mobilized into blood, and it can reflect the sum of previous lead exposure. 4.Urine lead: It has limited practical value and is often used as part of the lead repellent test. 5.Hair lead: A complete hair can record a history of lead exposure like a diary, and the lead content in each small section of hair can reflect the amount of lead exposure at the time of growth of that section of hair. (B) Other tests related to lead load: 1. peripheral blood picture; 2. lead repellent test; 3. porphyrin assay; 4. cerebrospinal fluid examination; 5. fecal occult blood test; 6. blood sugar; 7. X-ray examination; 8. lead examination of talcum powder. (C) Grading of lead poisoning in children – mainly based on blood lead level: Class I blood lead ≤ 100μg/L (relatively safe); Class II blood lead 100-199μg/L (mild lead poisoning); Class III blood lead 200-449μg/L (moderate lead poisoning); Class IV blood lead 450-699μg/L (severe lead poisoning); Class V blood lead 450-699μg/L (moderate lead poisoning); Class V blood lead ≤ 100μg/L (mild lead poisoning); Class V blood lead ≤ 100μg/L (moderate lead poisoning) Lead poisoning); Grade V Blood lead ≥700μg/L (as above); the last two grades are symptomatic lead poisoning. Differential diagnosis: 1. When gastrointestinal symptoms appear at the beginning of lead poisoning, it should be distinguished from acute gastroenteritis and viral hepatitis, etc. 2. 2. When there is abdominal colic, it should be distinguished from acute abdominal disease. 3. When signs of encephalopathy occur, it should be distinguished from encephalitis, tuberculous meningitis, brain tumor and hand-foot convulsion. 4. When there are symptoms and signs of peripheral neuritis, it should be distinguished from poliomyelitis and diphtheria nerve paralysis. The treatment of lead poisoning: 1. Principles: Combination of health education, environmental intervention and clinical treatment. Health education is the basic means, environmental intervention is the fundamental approach, and clinical treatment is the important link for children with moderate or above lead poisoning; the organic combination of the three is the fundamental guarantee for the successful treatment of lead poisoning in children. 2.Asymptomatic lead poisoning: Mild: blood lead is measured every three months, health education is the main way, oral consumption of lead-depleting food with lead repellent function; search for possible sources of lead pollution with the participation of public health personnel. Moderate: Blood lead is retested within one week, special tests are performed, and functional lead-depleting foods are taken when possible; environmental experts visiting the home to find the source of lead and intervene is the key. Severe: retest blood lead within 48 hours, hospitalization, lead expulsion treatment, environmental intervention. 3.Symptomatic lead poisoning: Blood lead ≥ 450μg/L, accompanied by one of the symptoms related to lead poisoning. The treatment principle is the same as that of severe lead poisoning. 4.Lead expulsion drugs: Disodium edetate calcium dimercaptopropionate Oral administration of dimercaptopropionic acid penicillamine. 5.Follow-up after lead expulsion: Blood lead measurement will be conducted again 7-21 days after the end of the course of treatment, and those who have rebound will proceed to the next course of treatment again. Health education: 1.General knowledge introduction. 2. Behavior guidance: wash hands regularly; cut nails regularly; clean toys regularly, etc. Use wet rags to wipe the dust in the living room near the roadside and industrial area, and do not play with lead work workers and roadside workers should clean before going home. Coal-burning families should open windows more often for ventilation; children should eat less food with high lead content; let off the overnight tap water for 1-5 minutes in the morning first. 3.Nutritional guidance: eat regularly, lead absorption increases when fasting. Sufficient calcium in food; sufficient amount of iron in food; sufficient amount of zinc in food; health food with lead repelling function. V. Environmental intervention: Remove lead paint, reduce lead dust, etc.