Will you get poisoned if a thermometer breaks?
Nov 24, 2025
Source: Cainiu Health
Dr. Ren Yi
Introduction
Thermometers contain liquid mercury, which easily volatilizes into mercury vapor at room temperature. If a thermometer breaks, promptly open windows for ventilation and use cardboard and tape to collect the mercury droplets, placing them into a sealed container; thoroughly clean the floor as well. This will rapidly reduce mercury vapor concentration, which generally will not reach toxic levels. However, if not cleaned up promptly, continuous volatilization of mercury may cause indoor mercury concentrations to exceed safety limits, potentially leading to symptoms such as headache, nausea, and vomiting upon inhalation.
Generally, breaking a thermometer will not cause poisoning if cleaned up promptly. However, failure to handle it properly may lead to mercury vapor accumulation and potentially result in poisoning. Seek medical attention immediately if any abnormalities occur. Detailed analysis is as follows:
Thermometers contain liquid mercury, which easily volatilizes into mercury vapor at room temperature. If the thermometer breaks, immediately open windows for ventilation and use stiff paper or adhesive tape to collect the mercury droplets into a sealed container, then thoroughly clean the affected area. This will rapidly reduce mercury vapor concentration, typically preventing levels from reaching those hazardous to health. However, if not cleaned promptly, continuous evaporation of mercury may cause indoor concentrations to exceed safety limits. Inhalation may lead to symptoms such as headache, coughing, nausea, vomiting, and limb tremors. Long-term exposure may damage vital organs including the nervous system and kidneys.
Vulnerable populations such as pregnant women, children, and individuals with weakened immune systems are more sensitive to mercury vapor; even minimal exposure may trigger noticeable discomfort. If proper protective measures—such as wearing masks and gloves—are not taken during cleanup, direct skin or respiratory contact with mercury may occur, increasing the risk of poisoning.
After a thermometer breaks, immediately open windows to ventilate, wear a mask and gloves to carefully collect mercury droplets, and avoid using vacuum cleaners or brooms. Wash hands thoroughly after cleanup and maintain indoor ventilation for at least 24 hours. Contact professional services for assistance when necessary.
