At the end of 2022, we made a science popularization on the cleaning method after breaking the mercury thermometer, teaching everyone how to deal with it scientifically, so as to achieve the prompt function of preventing mercury poisoning. In 2023, the number of relevant consultations reached a record high. Until the middle of April 2024, the "Will mercury poisoning be caused" or "How to deal with it" when mercury thermometers are accidentally broken remains very hot. See the following data.

Consultation on mercury at the National Poisoning Hotline

First, let's learn some basic knowledge:

   Why is mercury thermometer associated with mercury poisoning?

The mercury thermometer shell is made of fragile glass, and the content "mercury" is the common name of the metal "mercury". The commercially available thermometer contains about 1g of mercury. Metal mercury is liquid and volatile at room temperature. After the thermometer shell is damaged, mercury will overflow and volatilize into mercury vapor. The higher the ambient temperature is, the faster the volatilization will be. The space ventilation will also affect the diffusion of mercury vapor. If not cleaned in time, there is a risk of inhalation.

Damaged skin mucosa may be poisoned by mercury. If the mercury thermometer breaks the skin and there is mercury deposition at the wound, it will cause local inflammation if the wound is not cleared in time. Mercury is absorbed into the blood through the damaged skin mucosa, which can increase the risk of acute mercury poisoning.

The children are very curious when they see the bright mercury beads, and playing with them for a long time will increase the risk of mercury poisoning.

Eating a small amount of mercury by mistake will not cause poisoning. When taking the temperature, accidentally bite the thermometer and take a small amount of mercury orally. If the oral mucosa is not damaged, mercury poisoning will not occur. In order to reduce the risk, it is not recommended to measure the temperature in the mouth of infants with mercury thermometer.

   Did the consultant who broke the mercury thermometer have mercury poisoning?

Is mercury poisoning caused by accidentally breaking the mercury thermometer in daily life? In order to understand this problem, we have called some consultants for follow-up. In their first consultation, they described the following special circumstances:

(1) After breaking the thermometer, no mercury was cleaned for more than 12 hours, and someone stayed in that room all the time;

(2) At the time of consultation, there were dizziness, fever and other symptoms;

(3) There are infants, pregnant women, lactating women and the elderly at home.

Only two of the more than 100 people who were followed up by telephone had similar symptoms of mercury poisoning, one of whom was a 4-and-a-half year old child, and the other was an adult, but suffered from cancer and kidney disease, with low immunity. The two people recovered quickly after professional treatment. None of the others showed significant health effects.

   Is it because of mercury poisoning that you feel dizzy and weak after breaking the mercury thermometer?

If there are fever, dizziness, headache and other symptoms before the thermometer is broken, because there is no contact with mercury at this time, it can be determined that it has nothing to do with mercury poisoning.

So how to identify whether the symptoms are related to mercury poisoning?

The symptoms occurred within one week after the mercury thermometer was broken. Mercury poisoning was considered and relevant examinations were carried out only after other pathogenic reasons were excluded.

After breaking the mercury thermometer, in addition to the above symptoms, there are red flaky rash, insomnia, and oral gingivitis on the body surface, so mercury poisoning should be considered.

Special circumstances, such as high temperature environment, poor ventilation, long contact time, basic diseases of the contact person, etc.

If it is still impossible to identify, you can check the blood mercury or urine mercury in the local institutions with the ability to detect metal mercury, and judge whether further treatment is needed according to the inspection results. The results of trace element detection methods cannot be used as reference standards for mercury poisoning.

   If handled correctly, it will not be poisoned, so don't worry too much

1. Window opening ventilation is the most effective way to reduce the concentration of mercury vapor in the environment and reduce the inhalation of mercury vapor.

2. Timely clean the mercury that is visible to the naked eye and can be collected. It is recommended to use hard paper pieces for centralized collection, put them into plastic bottles, seal them, mark the words "mercury", and put them into outdoor hazardous dustbins as soon as possible. It is not recommended to use a vacuum cleaner or mop directly before collecting mercury. If mercury particles are occasionally found in a corner after a few weeks or months, it means that the ambient temperature is low and mercury volatilizes slowly, so there is no need to panic. You can clean up whenever you see it.

3. When the temperature plan breaks the skin or oral mucosa, the wound should be washed with flowing water in time, especially the silver white liquid particles. If there is no wound, there is no need to worry about poisoning. The complete skin mucosa will not be poisoned if it is exposed to mercury for a short time.

Conclusion: You should have known that there is no need to move out of the room because of breaking the thermometer, or be too worried about poisoning to sleep. After the mercury thermometer is broken, a certain degree of attention can be given. It is important to open a window for ventilation and timely treatment. In addition, normal life is not affected.

  (Contributed by Cheng Bowen and Jiang Shaofeng from the Occupational Health Institute of China Center for Disease Control and Prevention)