Mercury (Elemental): Lung Damaging Agent

CAS #:
7439-97-6

RTECS #: OV4550000

UN #: 2809 (Guide 172)

Common Names:

  • Elemental mercury
  • Liquid silver
  • Quicksilver

Agent Characteristics

Heavy, shiny, silver-white, mobile liquid metal, at room temperature.

Mercury exists naturally in the earth’s crust, and is released by degassing of the earth’s crust, volcanic emissions, and through evaporation. It can be obtained by heating mercury containing ores and condensing the vapors. Mercury is used in many industries, especially the electrical industry, and in many instruments such as thermometers and barometers. It has been used clinically, but because of its toxicity this use is diminishing. Most people are exposed to mercury through diet and dental fillings. Mercury is odorless. This card will only address elemental mercury.

  • Indoor Air: Mercury can be released into indoor air as a liquid spray (aerosol) or as a vapor.
  • Water: Mercury can be used to contaminate water.
  • Food: Mercury can be used to contaminate food.
  • Outdoor Air: Mercury can be released into outdoor air as a liquid spray (aerosol) or as a vapor.
  • Agricultural: If mercury is released into the air as a liquid spray (aerosol), it has the potential to contaminate agricultural products. If mercury is released as a vapor, it is highly unlikely to contaminate agricultural products.

Elemental mercury is toxic primarily through inhalation of mercury vapors. It is only slowly absorbed through the skin, although it may cause skin and eye irritation. Elemental mercury droplets may be absorbed through eye contact. Ingestion is not an important route of acute exposure as almost no elemental mercury is absorbed through the gastrointestinal tract.


Personal Protective Equipment

First Responders should use a NIOSH-certified Chemical, Biological, Radiological, Nuclear (CBRN) Self Contained Breathing Apparatus (SCBA) with a Level A protective suit when entering an area with an unknown contaminant or when entering an area where the concentration of the contaminant is unknown. Level A protection should be used until monitoring results confirm the contaminant and the concentration of the contaminant.
NOTE: Safe use of protective clothing and equipment requires specific skills developed through training and experience.

Select when the greatest level of skin, respiratory, and eye protection is required. This is the maximum protection for workers in danger of exposure to unknown chemical hazards or levels above the IDLH or greater than the AEGL-2.

  • A NIOSH-certified CBRN full-face-piece SCBA operated in a pressure-demand mode or a pressure-demand supplied air hose respirator with an auxiliary escape bottle.
  • A Totally-Encapsulating Chemical Protective (TECP) suit that provides protection against CBRN agents.
  • Chemical-resistant gloves (outer).
  • Chemical-resistant gloves (inner).
  • Chemical-resistant boots with a steel toe and shank.
  • Coveralls, long underwear, and a hard hat worn under the TECP suit are optional items.

Select when the highest level of respiratory protection is necessary but a lesser level of skin protection is required. This is the minimum protection for workers in danger of exposure to unknown chemical hazards or levels above the IDLH or greater than AEGL-2. It differs from Level A in that it incorporates a non-encapsulating, splash-protective, chemical-resistant splash suit that provides Level A protection against liquids but is not airtight.

  • A NIOSH-certified CBRN full-face-piece SCBA operated in a pressure-demand mode or a pressure-demand supplied air hose respirator with an auxiliary escape bottle.
  • A hooded chemical-resistant suit that provides protection against CBRN agents.
  • Chemical-resistant gloves (outer).
  • Chemical-resistant gloves (inner).
  • Chemical-resistant boots with a steel toe and shank.
  • Coveralls, long underwear, a hard hat worn under the chemical-resistant suit, and chemical-resistant disposable boot-covers worn over the chemical-resistant suit are optional items.

Select when the contaminant and concentration of the contaminant are known and the respiratory protection criteria factors for using Air Purifying Respirators (APR) or Powered Air Purifying Respirators (PAPR) are met. This level is appropriate when decontaminating patient/victims.

  • A NIOSH-certified CBRN tight-fitting APR with a canister-type gas mask or CBRN PAPR for air levels greater than AEGL-2.
  • A NIOSH-certified CBRN PAPR with a loose-fitting face-piece, hood, or helmet and a filter or a combination organic vapor, acid gas, and particulate cartridge/filter combination or a continuous flow respirator for air levels greater than AEGL-1.
  • A hooded chemical-resistant suit that provides protection against CBRN agents.
  • Chemical-resistant gloves (outer).
  • Chemical-resistant gloves (inner).
  • Chemical-resistant boots with a steel toe and shank.
  • Escape mask, face shield, coveralls, long underwear, a hard hat worn under the chemical-resistant suit, and chemical-resistant disposable boot-covers worn over the chemical-resistant suit are optional items.

Select when the contaminant and concentration of the contaminant are known and the concentration is below the appropriate occupational exposure limit or less than AEGL-1 for the stated duration times.

  • Limited to coveralls or other work clothes, boots, and gloves.

Emergency Response

  • Heating mercury vapor produces mercuric oxide, which is highly irritating to mucous membranes and more likely than elemental mercury vapor to adversely affect the lungs.
  • Elemental mercury reacts with most metals.
  • Elemental mercury reacts with many acids.
  • Elemental mercury reacts vigorously with ground mixtures of sodium carbide.
  • Mercury reacts with acetylenic compounds, ammonia, azides, oxygen, oxidants, and halogens.
  • A violent heat-producing (exothermic) reaction, possibly an explosion, occurs when mercury comes in contact with chlorine dioxide, lithium, rubidium, halogens, or acetylide.
  • Mercury and methyl azide are shock and electrical discharge sensitive.
  • Pure dry ammonia and mercury do not react even under pressure and heat, but if water is present, a compound forms that can explode during depressurization.
  • Upper and lower explosive (flammable) limits in air are not available for mercury.
  • Mercury is non-combustible.
  • The agent itself does not burn, but it may react upon heating to produce corrosive and/or toxic fumes.
  • Fire will produce irritating, corrosive, and/or toxic gases.
  • Use an extinguishing agent suitable for the type of surrounding fire.
  • Do not direct water at the heated metal.
  • Run-off may pollute waterways.
  • If the situation allows, control and properly dispose of run-off (effluent).
  • When any large container is involved in a fire, consider initial evacuation for 0.33 mi (500 m) in all directions.
  • This agent is not included in the DOT ERG2004 Table of Initial Isolation and Protective Action Distances.
  • In the DOT ERG 2004 orange-bordered section of the guidebook, there are public safety recommendations to isolate a mercury (Guide 172) spill or leak area immediately for at least 150 ft (50 m) in all directions.
  • Vapors are heavier than air and will collect and stay in poorly-ventilated or low-lying areas.
  • Hazardous concentrations may develop quickly in enclosed, poorly-ventilated, or low-lying areas.
  • Health: 1
  • Flammability: 0
  • Reactivity: 0
  • Special:

Health: 1, Flammability: 0, Reactivity: 0, Special:

  • OSHA: ID140
  • NIOSH: 6009
References are provided for the convenience of the reader and do not imply endorsement by NIOSH.
  • AIR MATRIX
    Chatterjee S, Pillai A, Gupta VK [2002]. Spectrophotometric determination of mercury in environmental sample and fungicides based on its complex with o-carboxy phenyl diazoamino p-azobenzene. Talanta 57(3): 461-465. Abstract.NIOSH [1994]. Mercury: Method 6009. In: NIOSH Manual of Analytical Methods. 4th ed. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-113.OSHA [1989]. Particulate mercury in workplace atmospheres, mercury: OSHA-SLTC Method ID-145. Salt Lake City, Utah: U.S. Department of Labor, Occupational Safety and Health.

    OSHA [1991]. Mercury vapor in workplace atmospheres: OSHA-SLTC Method ID-140. Salt Lake City, Utah: U.S. Department of Labor, Occupational Safety and Health.

    Singhvi R, Turpin R, Kalnicky DJ, Patel J [2001]. Comparison of field and laboratory methods for monitoring metallic mercury vapor in indoor air. J Hazard Materials 83(1-2):1-10.

    Temmerman E, Vandecasteele C, Vermeir G, Leyman R, Dams R [1990]. Sensitive determination of gaseous mercury in air by cold vapour atomic fluorescence spectrometry after amalgamation. Anal Chim Acta 236:371-376. Abstract.

    Yu JC, Zhang B, Lai Y-K [2000]. Direct determination of mercury in atmospheric particulate matter by graphite plate filtration–electrothermal atomic absorption spectrometry with Zeeman background correction. Spectrochim Acta B Atom Spectrosc 55(4):395-402.

  • OTHER
    No references were identified for this sampling matrix for this agent.
  • SOIL MATRIX
    Barshick CM, Barshick S-A, Britt PF, Lake DA, Vance MA, Walsh EB [1998]. Development of a technique for the analysis of inorganic mercury salts in soils by gas chromatography/mass spectrometry. Int J Mass Spectrom 178(1-2):31-41. Abstract.Götzl A, Riepe W [2001]. Mercury determination –– SPME and colorimetric spot test. Talanta 54(5):821-827. Abstract.López-García I, Sánchez-Merlos M, Hernández-Córdoba M [1997]. Determination of mercury in soils and sediments by graphite furnace atomic absorption spectrometry with slurry sampling. Spectrochim Acta B Atom Spectrosc 52(14):2085-2092. Abstract.

    Moreda-Piñeiro J, López-Mahía P, Muniategui-Lorenzo S, Fernández-Fernández E, Prada-Rodríguez D [2002]. Direct mercury determination in aqueous slurries of environmental and biological samples by cold vapour generation–electrothermal atomic absorption spectrometry. Anal Chim Acta 460(1):111-122.

    Vedrina-Dragojevic I, Dragojevic D, Cadež S [1997]. Spectrofluorimetric method for the determination of the total mercury content in sediment and soil. Anal Chim Acta 355(2-3):151-156. Abstract.

  • SURFACES
    No references were identified for this sampling matrix for this agent.
  • WATER
    EPA [1994]. Determination of metals and trace elements in water and wastes by inductively coupled plasma-atomic emission spectrometry, Method 200.7. In: Methods for the determination of metals in environmental samples supplement 1. Cincinnati, OH: U.S. Environmental Protection Agency. (EPA/600/R-94/111), National Technical Information Service, PB95-125472.EPA [1994].Mercury by cold vapor AA Spectrometry – Manual, Method 245.1. In: Methods for the determination of metals in environmental samples supplement 1. Cincinnati, OH: U.S. Environmental Protection Agency. (EPA/600/R-94/111), National Technical Information Service, PB95-125472.

Signs/Symptoms

Symptoms develop within a few hours of exposure to mercury.

Exposure to high levels of elemental mercury vapor produces acute health effects. Respiratory symptoms predominate, and they include cough and difficulty breathing or shortness of breath (dyspnea). Gastrointestinal effects, such as metallic taste, nausea, vomiting (emesis), diarrhea, and abdominal pain, are frequent. Central nervous system (CNS) effects are also common, and they include headache, weakness, and vision changes.

  • Irritation
  • Ingestion does not normally result in whole-body (systemic) toxicity.
  • Acute exposure to high levels of elemental mercury vapor may cause inflammation of the lungs (chemical pneumonitis), difficulty breathing or shortness of breath (dyspnea), chest pain, and dry cough. Effects may improve or, conversely, worsen, leading to fluid accumulation in the lungs (pulmonary edema), respiratory failure, and death. Acute toxicity may also cause kidney damage (sometimes severe) and kidney failure, rapid heart rate (tachycardia), and high blood pressure (hypertension). The patient/victim may have a metallic taste, salivation, difficulty swallowing (dysphagia), abdominal cramps, and diarrhea. Central nervous system (CNS) effects include headache, weakness, and visual disturbances.
  • Skin (dermal) reactions associated with skin contact with elemental mercury liquid or vapor are rare.
  • Rash or inflammation of the skin (contact dermatitis) are possible.
  • Acute contact with the skin does not normally result in whole-body (systemic) toxicity.

Decontamination

The purpose of decontamination is to make an individual and/or their equipment safe by physically removing toxic substances quickly and effectively. Care should be taken during decontamination, because absorbed agent can be released from clothing and skin as a gas. Your Incident Commander will provide you with decontaminants specific for the agent released or the agent believed to have been released.

The following are recommendations to protect the first responders from the release area:

  • Position the decontamination corridor upwind and uphill of the hot zone.
  • The warm zone should include two decontamination corridors. One decontamination corridor is used to enter the warm zone and the other for exiting the warm zone into the cold zone. The decontamination zone for exiting should be upwind and uphill from the zone used to enter.
  • Decontamination area workers should wear appropriate PPE. See the PPE section of this card for detailed information.
  • A solution of detergent and water (which should have a pH value of at least 8 but should not exceed a pH value of 10.5) should be available for use in decontamination procedures. Soft brushes should be available to remove contamination from the PPE.
  • Labeled, durable 6-mil polyethylene bags should be available for disposal of contaminated PPE.

The following methods can be used to decontaminate an individual:

  • Decontamination of First Responder:
    • Begin washing PPE of the first responder using soap and water solution and a soft brush. Always move in a downward motion (from head to toe). Make sure to get into all areas, especially folds in the clothing. Wash and rinse (using cold or warm water) until the contaminant is thoroughly removed.
    • Remove PPE by rolling downward (from head to toe) and avoid pulling PPE off over the head. Remove the SCBA after other PPE has been removed.
    • Place all PPE in labeled durable 6-mil polyethylene bags.
  • Decontamination of Patient/Victim:
    • Remove the patient/victim from the contaminated area and into the decontamination corridor.
    • Remove all clothing (at least down to their undergarments) and place the clothing in a labeled durable 6-mil polyethylene bag.
    • Thoroughly wash and rinse (using cold or warm water) the contaminated skin of the patient/victim using a soap and water solution. Be careful not to break the patient/victim’s skin during the decontamination process, and cover all open wounds.
    • Cover the patient/victim to prevent shock and loss of body heat.
    • Move the patient/victim to an area where emergency medical treatment can be provided.

First Aid

Initial treatment is primarily supportive of respiratory and cardiovascular function. Use caution when administering intravenous (IV) fluids when fluid accumulation in the lungs (pulmonary edema) is present.

There is no antidote for mercury toxicity. Chelation therapy may be warranted in some patient/victims following an assessment by a physician.

  • Immediately remove the patient/victim from the source of exposure.
  • Immediately wash eyes with large amounts of tepid water for at least 15 minutes.
  • Seek medical attention immediately.
  • Immediately remove the patient/victim from the source of exposure.
  • Ensure that the patient/victim has an unobstructed airway.
  • Do not induce vomiting (emesis).
  • Do not administer activated charcoal.
  • Ingestion of small amounts of mercury does not normally require treatment (decontamination).
  • If transport is necessary, prepare the transport vehicle in case the patient/victim vomits. The vomit may contain elemental mercury that can contaminate the transport vehicle. Have a suction apparatus ready and prepare several towels and double-sealable plastic bags to quickly clean and isolate vomitus. Only a professional mercury clean-up kit with a self-contained vacuum system should be used to decontaminate the transport vehicle. Ordinary vacuum cleaners can vaporize elemental mercury and increase the concentration of airborne mercury.
  • Seek medical attention immediately.
  • Immediately remove the patient/victim from the source of exposure.
  • Evaluate respiratory function and pulse.
  • Ensure that the patient/victim has an unobstructed airway.
  • If shortness of breath occurs or breathing is difficult (dyspnea), administer oxygen.
  • Assist ventilation as required. Always use a barrier or bag-valve-mask device.
  • If breathing has ceased (apnea), provide artificial respiration.
  • Seek medical attention immediately.
  • Immediately remove the patient/victim from the source of exposure.
  • See the Decontamination section for patient/victim decontamination procedures.
  • Seek medical attention immediately.
See ATSDR Medical Management Guidelines for Acute Chemical Exposures, Elemental Mercury https://www.atsdr.cdc.gov/MHMI/mmg46.pdf, for detailed recommendations.

Long-Term Implications

Chelation therapy may be considered for the patient/victim after consultation with a physician. However, the decision to chelate for a particular patient/victim should be made only by professionals experienced in the use of chelation, preferably in consultation with the regional poison control center. Chelation therapy becomes less effective in reducing the severity of poisoning and the risk of aftereffects (sequelae) as time after exposure increases.

Several days after the initial exposure, symptoms include heavy salivation (ptyalism), inflammation of the intestines (enteritis), and kidney (renal) damage. There can also be chronic central nervous system (CNS) effects, which develop as a result of the ability of absorbed elemental mercury to cross the blood-brain barrier. The acute mercury-induced lung damage usually resolves completely, but some cases of diffuse increased fibrous tissue in the lung (pulmonary fibrosis), restrictive lung disease, and chronic respiratory insufficiency have been reported.

Mercury is not classifiable as a carcinogen. It is unknown whether chronic or repeated exposure to mercury increases the risk of reproductive toxicity or developmental toxicity. Chronic or repeated exposure to mercury may cause lymphocyte aneuploidy. Menstrual disorders (dysmenorrhea) have been reported in female workers chronically exposed to mercury. An increased incidence of spontaneous abortion has been reported among wives of men chronically exposed to mercury. Mercury is known to cross the placental barrier. Repeated or continuous exposure to elemental mercury can result in accumulation of mercury in the body and permanent damage to the nervous system and kidneys. Classic health effects of poisoning include neurological and psychiatric effects, loss of kidney function, and inflammation of the upper airway and throat. Neuropsychiatric effects include tremor, anxiety, readily or frequently changing emotions (emotional lability), forgetfulness, insomnia, loss of appetite (anorexia), fatigue, and disturbances of thought and movement.


On-Site Fatalities

  • Consult with the Incident Commander regarding the agent dispersed, dissemination method, level of PPE required, location, geographic complications (if any), and the approximate number of remains.
  • Coordinate responsibilities and prepare to enter the scene as part of the evaluation team along with the FBI HazMat Technician, local law enforcement evidence technician, and other relevant personnel.
  • Begin tracking remains using waterproof tags.
  • Wear PPE until all remains are deemed free of contamination.
  • Establish a preliminary (holding) morgue.
  • Gather evidence, and place it in a clearly labeled impervious container. Hand any evidence over to the FBI.
  • Remove and tag personal effects.
  • Perform a thorough external evaluation and a preliminary identification check.
  • See the Decontamination section for decontamination procedures.
  • Decontaminate remains before they are removed from the incident site.
See Guidelines for Mass Fatality Management During Terrorist Incidents Involving Chemical Agents, U.S. Army Soldier and Biological Chemical Command (SBCCOM), November, 2001 for detailed recommendations.

Occupational Exposure Limits

  • NIOSH REL:
    • TWA (mercury vapor): 0.05 mg/m3 (skin)
    • Ceiling: 0.1 mg/m3 (skin)
  • OSHA PEL:
    • Ceiling: 0.1 mg/m3
  • ACGIH TLV:
    • TWA (8-hour): 0.025 mg/m3
  • NIOSH IDLH: 10 mg/m3
  • DOE TEEL:
    • TEEL-0: 0.025 mg/m3
    • TEEL-1: 0.1 mg/m3
    • TEEL-2: 2.05 mg/m3
    • TEEL-3: 4.10 mg/m3
  • AIHA ERPG:
    • ERPG-1: Not appropriate.
    • ERPG-2: 0.25 ppm
    • ERPG-3: 0.5 ppm

Acute Exposure Guidelines

Acute Exposure Guidelines [Interim]
10 min 30 min 60 min 4 hr 8 hr
AEGL 1
(discomfort, non-disabling) – mg/m3
NR NR NR NR NR
AEGL 2
(irreversible or other serious, long-lasting effects or impaired ability to escape) – mg/m3
3.1 mg/m3 2.1 mg/m3 1.7 mg/m3 0.67 mg/m3 0.33 mg/m3
AEGL 3
(life-threatening effects or death) – mg/m3
16 mg/m3 11 mg/m3 8.9 mg/m3 2.2 mg/m3 2.2 mg/m3

NOTE THAT VALUES ARE IN mg/m3, NOT ppm

NR = Not recommended due to insufficient data

Technical Support Document

IMPORTANT NOTE: Interim AEGLs are established following review and consideration by the National Advisory Committee for AEGLs (NAC/AEGL) of public comments on Proposed AEGLs. Interim AEGLs are available for use by organizations while awaiting NRC/NAS peer review and publication of Final AEGLs. Changes to Interim values and Technical Support Documents may occur prior to publication of Final AEGL values. In some cases, revised Interim values may be posted on this Web site, but the revised Interim Technical Support Document for the chemical may be subject to change. (Further information is available through AEGL Process).


Decontamination (Environment and Equipment)

The following methods can be used to decontaminate the environment/spillage disposal:

  • Do not touch or walk through the spilled agent if at all possible. However, if you must, personnel should wear the appropriate PPE during environmental decontamination. See the PPE section of this card for detailed information.
  • Keep combustibles (e.g., wood, paper, and oil) away from the spilled agent.
  • Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact the spilled agent.
  • Do not direct water at the spill or the source of the leak.
  • Stop the leak if it is possible to do so without risk to personnel, and turn leaking containers so that gas rather than liquid escapes.
  • Prevent entry into waterways, sewers, basements, or confined areas.
  • Isolate the area until gas has dispersed.
  • Ventilate the area.

Agents can seep into the crevices of equipment making it dangerous to handle. The following methods can be used to decontaminate equipment:

  • Not established/determined

Agent Properties

  • Chemical Formula:
    Hg
  • Aqueous solubility:
    Soluble
  • Boiling Point:
    674°F (356.72°C)
  • Density:
    Liquid: 13.534 at 77°F (25°C) (water = 1)
    Gas: 6.93 (air = 1)
  • Flammability:
    Not combustible
  • Flashpoint:
    Not established/determined
  • Ionization potential:

    Not established/determined

  • Log Kbenzene-water:
    Not established/determined
  • Log Kow (estimated):
    0.62
  • Melting Point:
    -102°F (-38.87°C)
  • Molecular Mass:
    200.59
  • Soluble In:

    Organic solvents

  • Specific Gravity:
    13.6 at 77°F (25°C)
  • Vapor Pressure:
    0.002 mm Hg at 77°F (25°C)
  • Volatility:
    Slightly volatile at room temperature.
    Significantly more volatile when heated.

Hazardous Materials Warning Labels/Placards

  • Shipping Name:
    Mercury
  • Identification Number:
    2809 (Guide 172)
  • Hazardous Class or Division:
    8
  • Subsidiary Hazardous Class or Division:
  • Label:
    Corrosive
  • Placard Image:
    dot_class8_corrosive

Trade Names and Other Synonyms

  • Colloidal mercury
  • Hg
  • Hydrargyrum
  • Kwik (Dutch)
  • Mercure (French)
  • Mercurio (Italian)
  • Mercury (Hg)
  • Mercury metal
  • Mercury vapor
  • Metallic mercury
  • Quecksilber (German)
  • Quick silver
Who to Contact in an Emergency

In the event of a poison emergency, call the poison center immediately at 1-800-222-1222. If the person who is poisoned cannot wake up, has a hard time breathing, or has convulsions, call 911 emergency services.

For information on who to contact in an emergency, see the CDC website at emergency.cdc.gov or call the CDC public response hotline at (888) 246-2675 (English), (888) 246-2857 (Español), or (866) 874-2646 (TTY).

Important Notice

The user should verify compliance of the cards with the relevant STATE or TERRITORY legislation before use. NIOSH, CDC 2003.