Description
Mercury is found in trace amounts in the air, but the largest
deposits on earth are as cinnabar (mercuric sulfide). It exists in
several forms such as a liquid metal (quicksilver), as a vapor,
and in compounds (organic and inorganic). Mercury has been
used as a medicine, to make amalgams, and in many industrial
applications. Exposure to mercury can be toxic in any of its
forms, in any route (ingestion, skin contact, and inhalation)
depending on the dose and duration of exposure. Thermometers,
‘button’ batteries, the new energy-saving fluorescent light
bulbs, and many seafood (shellfish, tuna, marlin, and many
others) contain mercury, and are, therefore, potential sources
of mercury poisoning. The primary intracellular target of
mercury is the sulfhydryl groups in many tissue enzymes and
proteins. Binding of –SH– groups paralyzes vital functions,
eventually causing failure of organ systems such as the lungs,
kidneys, or the nervous system.
Industrial disasters cause release of mercury or methylmercury
into the environment. The classic example of such
a disaster is the contamination of Minamata Bay in Japan,
where the term Minamata disease originated. Studies from
about 1956 to 1960 suggested the unusual symptoms
(neurological) found in people in this area was traced back to
industrial wastewater containing methylmercury. Nearly 2200
people were diagnosed and over 1700 deaths were eventually
attributed to methylmercury poisoning. Mercury has been used
in skin creams; the most recent problem cream was identified
in 1996 from Mexico named ‘Crèma de Belleza-Manning.’
Mercury poisoning can be caused by all forms of mercury
(elemental, vapor, inorganic, and organic).
Chemical Properties
Mercury bichloride is an odorless white crystalline solid.
Chemical Properties
Mercuric chloride,HgC12, is white crystals that are soluble in water and alcohol that melt at 276℃ and boil at 302℃. Highly toxic and corrosive, it is used in the manufacture of mercury compounds, in organic synthesis, as a reagent and catalyst, as a fungicide, insecticide, and wood preservative, and for many other purposes.
Uses
Mercuric chloride is used in preservatives for wood and
anatomical specimens, embalming solutions, disinfectants,
photographic intensifiers, leather tanning, seed treatments,
analytical reagents for organic syntheses, and the manufacture
of other mercury-containing compounds. Pharmaceuticals
containing mercuric chloride have also been used therapeutically
as topical antiseptics and disinfectants.
Uses
Mercuric chloride is used in tanning leather; intensifier in photography; topical antiseptic and disinfectant.
Uses
Preserving (kyanizing) wood and anatomical specimens; also embalming; disinfecting; browning and etching steel and iron; intensifier in photography; white reserve in fabric printing; tanning leather; electroplating aluminum; depolarizer for dry batteries; freeing gold from lead; magic photograms; mordant for rabbit and beaver furs; staining wood and vegetable ivory pink; manufacture of ink for mercurography; treating seed potatoes; manufacture of other mercury Compounds. As an important reagent In animal chemistry.
Definition
ChEBI: A mercury coordination entity made up of linear triatomic molecules in which a mercury atom is bonded to two chlorines. Water-soluble, it is highly toxic. Once used in a wide variety of applications, including preserving wood and anatomical specimens, emba
ming and disinfecting, as an intensifier in photography, as a mordant for rabbit and beaver furs, and freeing gold from lead, its use has markedly declined as less toxic alternatives have been developed.
Production Methods
Commercial production of mercuric chloride typically involves the reaction of elemental mercury with chlorine gas or mercuric sulphate with sodium chloride. In one common method, mercury is first oxidised by chlorine to form mercuric chloride directly, a process carried out in controlled reactors due to the toxic and volatile nature of the reactants. Alternatively, mercuric sulphate can be treated with sodium chloride in aqueous solution, precipitating mercuric chloride, which is then purified through crystallisation.
General Description
An odorless white crystalline solid. Density 5.4 g / cm3. Melting point 277°C. Slightly volatile at ordinary temperatures. Can be sublimed unchanged. Corrosive to the mucous membranes. Toxic by inhalation (dusts, etc.), ingestion, and skin absorption. Used in photography, disinfectants, wood preservatives, fungicides.
Air & Water Reactions
Slightly soluble in water.
Reactivity Profile
Mercury chloride is decomposed by sunlight. Incompatible with formates sulfites, phpophosphites, phosphates, sulfides, albumin, gelatin, alkalis, alkaloid salts, ammonia, lime water, antimony, arsenic, bromides, borax, carbonates, reduced iron, iron, copper, lead and silver salts, infusions of cinchona, oak bark or senna, tannic acids and vegetable astringents. .
Hazard
Toxic by ingestion, inhalation, and skin
absorption; a poison.
Health Hazard
Mercury chloride is classified as extremely toxic. All forms of mercury are poisonous if absorbed. Probable oral lethal dose is 5-50 mg/kg; between 7 drops and 1 teaspoonful for a 150 lb. person. Mercury chloride is one of the most toxic salts of mercury. Material attacks the gastrointestinal tract and renal systems.
Fire Hazard
Material may explode on heating, with friction, or contact with alkali metals, sulfides, acetylene, ammonia, and oxalic acid. Upon decomposition highly toxic chloride and mercury fumes are emitted. Avoid formates, sulfites, hypophosphites, phosphates, sulfides, albumin, gelatin, alkalies, alkaloid salts, ammonia, lime water, antimony, arsenic, bromides, borax, carbonates, reduced iron, copper, iron, lead, silver salts, infusions of cinchona, columbo, oak bark or senna, and tannic acid. Mercury chloride may explode with friction or application of heat. Mixtures of Mercury chloride and sodium or potassium are shock sensitive and will explode on impact. Avoid contact with acids or acid fumes.
Mechanism of action
A non-specific, multi-site fungicide. It disrupts essential enzymatic activities in fungal cells, interferes with mitochondrial respiration and inhibits carbohydrate synthesis in fungal mycelia. The compound can also alter membrane permeabilit
Safety Profile
A human poison by
ingestion. Poison experimentally by
ingestion, skin contact, and subcutaneous
routes. Human systemic effects by ingestion:
respiratory obstruction, nausea or vomiting,
urine volume decrease or anuria. Human
reproductive effects by ingestion: terminates
pregnancy. Experimental teratogenic and
reproductive effects. Human mutation data
reported. Questionable carcinogen. A severe
eye and skin irritant. Reaction with sodmm
aci-nitromethanide + acids forms the
explosive mercury fulminate. Reacts
violently with K, Na. When heated to
decomposition it emits toxic fumes of Hg.
Potential Exposure
Mercuric chloride is used as dip for
bulbs and tubers; for earthworm control; as repellent to
ants, roaches, etc.; in preserving wood and anatomical
specimens; embalming, browning, etching steel and iron;
as a catalyst for organic synthesis; disinfectant, antiseptic,
tanning; textile printing aid; manufacture of dyes; in
agricultural chemicals; dry batteries; pharmaceuticals, and
photographic chemicals
First aid
If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 min, occasionally lifting upper and lower lids. Seek 1686 Mercuric chloride medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit. Medical observation is recommended for 2448 h after breathing overexposure, as pulmonary edema may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consider administering a corticosteroid spray. Antidotes and special procedures for medical personnel: The drug NAP (n-acetyl penicillamine) has been used to treat mercury poisoning, with limited success. Note to physician: For severe poisoning BAL [British AntiLewisite, dimercaprol, dithiopropanol (C3H8OS2)] has been used to treat toxic symptoms of certain heavy metals poisoning including mercury. Although BAL is reported to have a large margin of safety, caution must be exercised, because toxic effects may be caused by excessive dosage. Most can be prevented by premedication with 1-ephedrine sulfate (CAS: 134-72-5).
Environmental Fate
Mercury adsorbed from mercuric chloride and 2-methoxyethylmercury
chloride (Aretan) solutions by three contrasting
soils showed a dependence on soil–solution ratio and initial
mercury (Hg) concentration in soil solution. Changing the
soil–solution ratio from 1:10 to 1:100 but keeping the initial
concentration constant resulted in an increase in initial
concentration but, on the other hand, resulted in decrease in
Hg adsorption. Upon manipulation of the pH of the surface
soils, adsorption of mercuric chloride at 100 mg Hg l
-1
concentration increased from ～ 70 to over 95 mg Hg kg
-1
when the pH was raised from 5.0 to 8.0. Precipitation of Hg
may also have contributed to this trend. Removal of organic
matter from soil resulted in large reductions of Hg adsorbed, as
much as 95% from the mercuric chloride solutions. Mercuric
compounds found in the atmosphere are likely to be transformed
by chemical or physical processes. Theoretical calculations
on the photodissociation of mercuric compounds have
indicated that mercuric chloride and mercuric cyanide are
stable, while mercuric hydroxide may dissociate in the gas
phase. Exchange reactions between water and mercury
compounds are likely to occur in the atmosphere. These
exchange reactions eventually result in the release of elemental
mercury into the gaseous phase.
storage
Color Code—Blue: Health Hazard/Poison: Store in a secure poison location. Prior to working with this chemical you should be trained on its proper handling and storage. Mercuric chloride must be stored to avoid contact with potassium and sodium, since violent reactions occur. See also “Incompatibilities,” above. Store in tightly closed containers in a cool, well-ventilated area.
Shipping
UN1624 Mercuric chloride, Hazard Class: 6.1;
Labels: 6.1-Poisonous materials.
Purification Methods
It is soluble in EtOH and is extracted into Et2O from an aqueous solution. It is very POISONOUS and 0.2-0.4g is fatal. The antidote is immediate administration of white of egg as an emetic.
Toxicity evaluation
A reference from Middle Ages in Goldwater’s book on mercury
describes oral ingestion of mercury as causing severe abdominal
cramps, bloody diarrhea, and suppression of urine. This is
an accurate report of the effects following accidental or suicidal
ingestion of mercuric chloride. Injection of mercuric chloride
produces necrosis of the epithelium of the pars recta kidney.
Cellular changes include fragmentation and disruption of the
plasma membrane and its appendages, vesiculation and
disruption of the endoplasmic reticulum and other cytoplasmic
membranes, dissociation of polysomes and loss of ribosomes,
mitochondrial swelling and loss of amorphous intramatrical
deposits, and condensation of nuclear chromatin. Although
exposure to a high dose of mercuric chloride is directly toxic to
renal tubular lining cells, chronic low-dose exposure may
induce an immunologic glomerular disease. This form of
chronic mercury injury to the kidney is clinically the most
common form of mercury-induced nephropathy. Experimental
studies have shown that the pathogenesis of chronic mercury
nephropathy has two phases: an early phase characterized by
anti-basement membrane glomerular nephritis followed by
a superimposed immune complex glomerulonephritis with
transiently raised concentrations of circulating immune
complexes.
Incompatibilities
A strong reducing agent; keep away
from oxidizers. Mercuric chloride may explode with friction or application on heat. Mixtures of mercuric chloride
and sodium or potassium are shock sensitive and will
explode on impact. Avoid contact with acids or acid fumes.
Also avoid the presence of formats, sulfites, hypophosphites, phosphates, sulfide; albumin, gelatin, alkalies,
alkaloid salts; ammonia, lime water; antimony, arsenic,
bromides, borax, carbonates, reduced iron, copper; iron,
lead, silver salts; infusions of cinchona; columbo, oak bark
or senna; and tannic acid
