Authors: CANUTEC Emergency Response Advisors
For immediate help, moderate to serious exposures, call 911 or the Poison Control Centre in your area and seek medical treatment, and refer to the first aid section.
For technical help, call CANUTEC at 613-996-6666 and refer to the spill response section.
Mercury, once a staple in manufacturing of thermometers and other articles, has come under scrutiny due to hazards it poses. Every year, CANUTEC receives many calls about possible mercury spills from broken equipment like:
- thermometers
- fluorescent lamps (CFL bulbs)
- barometers
- thermostats
This article summarizes information on mercury and mercury spills gathered by CANUTEC Emergency Response Advisors.
On this page
- Introduction
- Potential hazards
- First aid
- Handling
- Storage
- Fire response
- Spill response and disposal
- Conclusion
- References
Introduction
Mercury is the only metal on earth that is liquid at room temperature. Mercury has been used in the manufacturing of thermometers for over 300 years because of its liquid state and how it expands when heated, which allows us to read the temperature markings on the thermometer.
Mercury is still used in:
- fluorescent lamps
- thermostats
- float valves
- producing other chemicals
- liquid mirrors
Mercury is considered safe when it’s properly contained in these items or a sealed environment. In fact, the immediate danger when an item containing mercury breaks is glass fragments. This is because mercury isn’t a short-term hazard.
Recently made thermometers do not contain mercury. The Products Containing Mercury Regulations were amended in 2015. They say that a person must not manufacture or import any product that contains mercury unless they meet specific conditions. For example, specialized laboratory equipment containing mercury is allowed. There are also alcohol and digital thermometers with similar and better ranges to mercury ones.
Galinstan is a non-toxic metal alternative used in modern thermometers. This metal alloy is composed of mostly Gallium (Ga), Indium (In) and Tin (Sn). The exact proportions depend on the brand. Galinstan has the same silver-liquid-like appearance and texture as mercury.
At a quick glance, galinstan could easily be mistaken for mercury. The best way to tell them apart is by their behaviour and appearance.
Mercury:
- forms round beads that look solid:
- if the beads are wiped down, they will break into smaller beads instead of smudging or spreading out like water
- spilled mercury tends to spill in all directions as small beads:
- this means mercury beads can often be found across the room from the spill, not just near the spill
- does not stain
Galinstan:
- tends to “stick” to a lot of different materials
- when wiped down, it will break into smaller “puddles” that also spread and smudge
- once smudged, the texture is more like viscous (thick) water than mercury beads
- stains silver when smudged
Potential hazards
Hazards of mercury
The main hazard of mercury is long-term inhalation (breathing in) of its vapours. It’s important to note that under normal temperatures, mercury won’t produce many vapours as mercury’s vapour pressure is 0.0002 mmHg, which can be considered almost negligeable. However, mercury can release vapours over time and with temperature changes. Breathing in mercury vapours over a long time can harm the nervous system, lungs, and kidneys. Its vapours can easily pass from the lungs to the bloodstream.
Mercury exposure is most dangerous in small, confined, and poorly ventilated areas. Mercury containing equipment like thermometers must be handled with care to avoid breathing in the vapours if there is a leak or if the thermometer breaks. Although short-term exposure isn’t usually dangerous, avoid direct contact, such as touching the metal or ingesting (swallowing).
Mercury is a corrosive metal. Prolonged contact can cause irritation or chemical burns. You should wear gloves when handling mercury.
Hazards of galinstan
The main hazard of galinstan is that it’s corrosive. Galinstan can cause chemical burns to the skin and prolonged contact can cause irritation. You should wear gloves when handling galinstan. Continuous or repeated skin contact can also cause dry skin. It doesn’t present any fire or explosion risk. Just like mercury, it doesn’t produce much vapour and isn’t an immediate inhalation hazard.
First aid
Mercury poisoning symptoms may include:
- slight muscular tremor
- loss of appetite
- nausea
- diarrhea
In the case of exposure with mercury and galinstan
Eyes: Immediately flush the eyes with large amounts of water for at least 20 minutes. Occasionally lift the lower and upper eyelids.
Skin: Wash down the skin area with water and soap. For mercury exposure: Remove any contaminated clothing. Quickly and gently blot or brush away the excess mercury. Wash gently and thoroughly with lukewarm water and soap for 5 minutes.
Inhalation: Supply fresh air. Keep the affected person warm and at rest. Get medical attention if needed. For mercury inhalation: If the person inhaled a large amount of mercury, move them to fresh air immediately. If they have stopped breathing, perform artificial respiration (CPR). Keep the affected person warm and at rest. Get medical attention as soon as possible.
Ingestion: If someone has swallowed mercury or galinstan, seek medical attention immediately.
Handling
Make sure that you wear proper personal protective equipment (PPE), such as gloves and safety glasses. Make sure there is proper ventilation before handling mercury or galinstan.
Storage
Keep mercury thermometers out of direct sunlight, in a safe, cool, and dry area away from heat sources. Keep them out of reach of young children and pets. We recommend properly disposing of thermometers that might contain mercury and replacing them with a less or non-hazardous alternative, like a galinstan or digital thermometer.
Fire response
Mercury itself doesn’t burn. However, if it is heated or involved in a fire, it can decompose and release toxic vapours and fumes like mercury vapour and mercuric oxide. You must be cautious if a fire or explosion occurs in an area or building containing mercury and ensure the following:
- evacuate the area and approach the fire from upwind
- use water spray or fog to absorb heat and keep containers or tanks exposed to fire cool
- if possible, isolate mercury materials not yet exposed to the fire and move containers away
- do not spray water directly on heated metal
Spill response and disposal
For technical advice, contact CANUTEC at 1-888-226-8832 (Canada and US only), 613-996-6666, or *666 (cell phone only).
If the spill is on a hard surface
Mercury spills can be cleaned using various household items. Some common tactics include:
- scooping mercury beads between two playing cards or any other firm paper
- sucking up mercury beads using an eye dropper or syringe
- using adhesive tape to pick up mercury beads from hard-to-reach corners or cracks
- directing mercury beads using a disposable rubber squeegee
- turning off all lights and shining a flashlight across the floor; hard to find mercury beads will reflect the light like a mirror
You should place mercury beads and all tools used for cleanup a sealable bag or glass jar. Make sure the bag or jar is airtight so that no vapours escape. Use tape or a damp paper towel to pick up smaller pieces of glass. Bring them to your local hazardous waste facility for proper disposal.
You should never dispose of mercury by pouring it down the drain. Mercury is heavier than water. It can accumulate in the drain and emit vapours over time.
After picking up all the mercury beads, clean the surfaces that have been in contact with mercury with water and soap. You can shake off and ventilate contaminated clothing outside. Ventilate and air out the space where the spill occurred.
If you frequently use the affected room, there should be enough ventilation to naturally disperse the leftover mercury vapours. For rooms with lower traffic, you should circulate air with the help of a fan and open the windows.
We do not recommend using a home vacuum to pick up the mercury beads. This can cause mercury droplets to nebulize (become a fine mist) and increase the risk of mercury vapours being spread back into the home and inhaled. Mercury residue may also remain trapped inside the vacuum. However, if you use a vacuum, you can empty the contents of the vacuum and place them with contaminated tools. Clean the vacuum so that it can be used afterwards. As an extra safety precaution, you can run the vacuum outdoors for 15 to 30 minutes.
We also do not recommend using a broom on a mercury spill. This will scatter the mercury droplets, making them harder to find and pick up afterwards.
You should not attempt to clean the spill by yourself if:
- you are dealing with a large spill
- the spill happened in a public area
- you are pregnant or expecting to be pregnant within the year
If the spill is on a soft surface
Mercury beads are very difficult to clean from carpets. The carpeting can be carefully removed and thrown out. Do not wash mercury contaminated clothing and items in the washing machine. Contaminated materials like cushions, rugs or stuffed toys should be sealed in a trash bag then sealed inside another bag for extra precaution. Store everything in a secure, non-living space (like the garage) until they can be brought to your local hazardous waste facility for proper disposal.
Galinstan spills
You should sweep or wipe up spilled galinstan and put the waste into plastic containers for proper disposal. You can also use an eye dropper or syringe to suck up the galinstan spill. Clean any residue on the surface with a water and soap solution and rinse to remove any residue. You can consult the safety data sheet (SDS) of the galinstan-containing equipment for more instructions and cleanup steps.
Conclusion
While the use of mercury in articles such as thermometers, barometers, and CFL bulbs has been valued for its precision and reliability, the potential hazards it can pose makes it not unsuitable for everyday use. New thermometers sold in Canada no longer contain mercury. You can consult this article for advice on how to clean up a spill and dispose of the broken equipment containing mercury.
It’s important to remember that mercury is a long-term inhalation hazard. Its short-term hazards aren’t critical nor life-threatening. If the spill is properly cleaned up right away, there shouldn’t be serious safety concerns. If you have any doubt, you can call CANUTEC for additional technical advice on mercury spills.
References
- RI Department of Health, “Mercury in Thermometers”, [Online]. Available: https://dem.ri.gov/sites/g/files/xkgbur861/files/programs/benviron/waste/pdf/therms.pdf
- Canadian Centre for Occupational Health and Safety, “Mercury”, [Online]. Available: https://ccinfoweb2.ccohs.ca/cheminfo/records/322E.html
- D.R. Lide, “Handbook of Chemistry and Physics”, CRC Press, pp. 4.125–4.126, 2005.
- J. Meija, et al. "Atomic Weights of the Elements 2013 (IUPAC Technical Report)," Pure and Applied Chemistry, vol. 88, no. 3, pp. 265–91, 2016.
- EPA, “How People are Exposed to Mercury,” [Online]. Available: https://www.epa.gov/mercury/how-people-are-exposed-mercury
- B. Littlefied, “Why it is that mercury is chosen for thermometers?”, [Online]. Available: https://www.ucl.ac.uk/culture-online/case-studies/2022/apr/why-it-mercury-chosen-thermometers
- South Carolina Department of Health and Environmental Control, “Health Risks of Mercury,” [Online]. Available: https://scdhec.gov/environment/your-homyee/mercury/health-risks-mercury
- CDC National Institute for Occupational Safety and Health (NIOSH), “Mercury compounds [except (organo) alkyls] (as Hg)”, [Online]. Available: https://www.cdc.gov/niosh/npg/npgd0383.html
- Michigan Department of Community Health, “How to Clean Up Spilled Mercury (for Homes)”, v.18, 2014, [Online]. Available: https://www.michigan.gov/mdhhs/safety-injury-prev/environmental-health/topics/mercury/homes