A thermometer mercury is about 1 gram, this dose is not enough to cause death by poisoning, but there may be some toxic side effects, but the specific situation needs to be different from person to person. Mercury is a heavy metal, usually in liquid form, volatile and can cause protein denaturation upon exposure. If the patient is exposed to less mercury, the symptoms of poisoning are mild, usually 1-2 days may appear gum swelling, bleeding, nausea, vomiting and other gastrointestinal symptoms, which can be recovered by effective treatment and usually do not lead to death. If the patient is exposed to a large amount of mercury for a long time, the symptoms of its poisoning are generally more serious, which will cause irreversible damage to organ functions and even trigger organ failure, such as acute renal tubular necrosis, acute renal failure, respiratory failure, etc., which may eventually lead to the death of the patient, but the specific time of death cannot be determined and needs to be determined according to the specific condition and medical intervention. Therefore, the mercury dose in the thermometer is small and not harmful to humans. However, once the human body is exposed to mercury, should be promptly to the hospital emergency by a professional doctor for symptomatic treatment, so as not to cause other physical discomfort.