Carbamyl poisoning

　　Poisoning can occur through accidental ingestion of this type of pesticide, skin contact, or inhalation of its mist droplets. Acute carbamate poisoning is mainly due to pesticide applicators not wearing protective clothing and masks, leakage of applicators, and protective gloves of carbamate finished product packaging workers breaking, resulting in a large amount of carbamate contamination of the skin and inhalation through the respiratory tract; acute poisoning can also occur when ingesting or self-administering 25% carbamate mother liquid.

　　The mechanism of carbamate poisoning is relatively complex. The main mechanism may be direct anesthesia and inhibition of the cardiovascular system. The aniline active group of carbamate and its metabolites can cause methemoglobinemia and hemorrhagic cystitis. Carbamate inhibits monoamine oxidase and other enzymes in the blood, leading to a complex clinical presentation.

　　Occupational poisoning is mainly absorbed through the skin and respiratory tract. Symptoms generally appear 2-4 hours after exposure to carbamate, while oral poisoning may occur within half an hour to one hour after ingestion.

　　1. Mild poisoning

　　Common symptoms include headache, dizziness, mental depression, fatigue, palpitations, nausea, drowsiness, and mild cyanosis.

　　2. Moderate poisoning

　　In addition to the exacerbation of the above symptoms, there may be shallow coma, cyanosis of the skin and mucous membranes, frequent urination, urgency, dysuria, hematuria, and other symptoms of hemorrhagic cystitis. Some patients may have fever, decreased or increased blood pressure, tachycardia, and arrhythmia.

　　3. Severe poisoning

　　Symptoms include coma, marked cyanosis, dilated pupils, shock, respiratory failure, and heart failure. A few patients may develop pulmonary edema, acute renal failure, upper gastrointestinal bleeding, hemolytic anemia, disseminated intravascular coagulation, brain edema, and cardiac arrest. Local skin redness and millet-like skin rash may be accompanied by burning pain and itching.

　　Acute poisoning with mild symptoms includes nausea, vomiting, dizziness, fatigue, drowsiness, sweating, bradycardia, cold extremities, with drowsiness as the prominent manifestation. Severe cases may present with deep coma, disappearance of reflexes, and even death due to respiratory and circulatory failure. Poisoning patients often have frequent urination, urgency, dysuria, hematuria, proteinuria, cyanosis, and other symptoms. Skin contact with the poison may cause burning, numbness, and itching, with local appearance of millet-like papules. Therefore, drowsiness, cyanosis, and hemorrhagic cystitis are the main characteristics of severe poisoning.

　　I. Disease Prevention

　　1. Improve the packaging machine and workers of carbamate mother liquid, as well as the labor protection supplies for applicators, to prevent external leakage and skin contamination.

　　2. Medical personnel should be vigilant about carbamates and other pesticides, especially the mixed poisoning of organophosphorus insecticides, which may lead to misdiagnosis or missed diagnosis, resulting in the loss of the opportunity for rescue.

　　II. Safety Tips

　　1. Avoid accidental ingestion or poisoning due to accidents or negligence in protection during production, packaging, storage, transportation, and use, and refer to the treatment for oral poisoning for symptoms after absorption.

　　2. In cases of oral poisoning, vomiting induction, gastric lavage (using a 1% to 2% sodium bicarbonate solution), catharsis, fluid replacement, and diuresis should be used to promote the excretion of toxins. Individuals with cyanosis can be treated with methylene blue, glucose solution, and intravenous injection of vitamin C. Hematuria can be treated with adrenal cortical hormones.

　　3. In cases of skin contact or inhalation of poisoning, immediately脱离 contact with the environment and wash the contaminated areas with soap and water. Refer to the treatment for oral poisoning for symptoms after absorption.

　　The urine may contain red blood cells, protein, a small number of white blood cells, and casts. A few patients may have an increased serum ALT, and the level of carbaryl and its metabolite 4-chloro-o-toluidine in the urine may increase (the normal value is 0.02 ± 0.025 mg/L, of which carbaryl is 0.01 ± 0.023 mg/L, and 4-chloro-o-toluidine is 0.010 ± 0.16 mg/L). The level of methemoglobin in the blood increases, and in severe poisoning, the level of monoamine oxidase in the blood decreases. The electrocardiogram may show arrhythmias and myocardial damage.

　　1. Patients with carbaryl poisoning should eat

　　Diet should be light, with a preference for liquid and easily digestible foods. Pay attention to a nutritious diet and eat more chicken, lean meat, eggs, dairy products, millet, corn, jujube, silver ear, lily, chestnut, white fungus, and other foods, as well as fresh vegetables such as cabbage, lotus root, cucumber, watermelon, apple, and pear, which are high in nutrition, rich in vitamins and fiber.

　　2. Patients with carbaryl poisoning should avoid eating

　　Avoid smoking and drinking, and avoid spicy and刺激性 food.

　　Oral poisoning should be treated with vomiting induction, gastric lavage (using a 1% to 2% sodium bicarbonate solution), catharsis, fluid replacement, and diuresis to promote the excretion of toxins; individuals with cyanosis can be treated with methylene blue, glucose solution, and intravenous injection of vitamin C; hematuria can be treated with adrenal cortical hormones. Other treatments are symptomatic.