Can a broken thermometer cause mercury poisoning?

A broken thermometer usually does not lead to mercury poisoning. The amount of mercury in a thermometer is about 0.5 grams, and mercury evaporates slowly at room temperature. As long as it is properly handled promptly, avoiding prolonged exposure or inhalation of high-concentration mercury vapor, poisoning will not occur. If mishandled and symptoms such as headache, nausea, or fatigue appear, medical attention should be sought promptly.

Mercury is chemically stable and exists as a liquid at room temperature. It takes time for mercury to volatilize into vapor, and if windows are opened promptly after a small amount of mercury vapor enters the indoor air, the concentration drops rapidly—insufficient to pose a health risk. Mercury poisoning occurs only through inhalation of mercury vapor via the respiratory tract; direct skin contact with liquid mercury generally does not result in absorption.

It is important to avoid improper cleanup methods, such as touching mercury directly with hands, sweeping it into drains or trash bins, which may cause mercury to spread or remain residual over time. Only in cases of large-scale mercury leakage within a confined space without timely cleanup might poisoning occur due to inhalation of high-concentration mercury vapor. The amount of mercury in a single thermometer is far below this risk threshold.

When cleaning up, open windows first to ventilate. Use stiff paper or adhesive tape to collect scattered mercury droplets, place them into a sealed container for proper disposal, and avoid direct hand contact or using a vacuum cleaner. When storing thermometers daily, keep them away from areas accessible to children to prevent accidental breakage and reduce risks.