Toxicology - Metallic poisons - Mercury

1. MERCURY POISONING
Forensic Medicine and Toxicology

2. o Quick Silver
o Hydrargyrum
o Para
o Padarasa
Also known as.....
MERCURY

3. Exists as…..
Metallic Hg0
Mercurous
Hg2
2+
Mercuric
Hg2+

4. ELEMENTAL MERCURY
• Heavy metal
• Bright and silvery
• Liquid at room temperature
• Used in some thermometers, dental
amalgams, fluorescent light bulbs,
some electrical switches, mining,
and some industrial processes.
• Released into the air when coal and
other fossil fuels are burned.
• Toxicity:
• NON TOXIC if swallowed as
liquid
• ACUTE TOXICITY if inhaled as
vapour

5. Inorganic Mercurial
Compounds
Mercuric chloride Mercuric oxideMercuric sulphide Mercurous chloride

6. DISINFECT WOUNDS
TAXIDERMY
VERMILION
TATTOOING
ANTISEPTICS
LAXATIVE
TEETHING POWDER
BATTERIES
OINMENTS
Calomel
Corrosive sublimate
Cinnabar
Sipichand
USES

7. Medicinal preparationsNeptal
Thiomerin sodium
(mercaptomerin sodium)
Mecurophyllin
Used as diuretics and has low toxicity when
used in therapeutic doses
Metaphen
Merthiolate (thiomersalate)
Used as antiseptics for sterilizing skin and
instruments
Diethyl dimethyl mercury
Mercuric methide
Used as fungicides
Mercury is methylated
under sea water and
certain sea fishes,
particularly sword fish,
are rich in
methylmercury
Organic Mercurial
Compounds

8. Absorption
Mercuric chloride and some
other mercurial salts
Ingestion
Soluble in gastric juice
Readily absorbed through git
Vapour of mercury and soluble
mercury salts
Inhalation
Ingestion
Topical
well-absorbed through the respiratory
tract, vaginal tract (douche), urinary
bladder (mercurial antiseptic washing
agent)
Metallic mercury
Ingestion
Not absorbed

9. Fate
After absorption, mercury gets deposited in all tissues of the body, particularly in liver, kidneys, spleen
and bones.
The mercuric ion binds with sulfhydryl groups of enzymes and cellular proteins, nucleic acid and mitotic
apparatus interfering with enzyme and cellular transport functions.
Mercury, after absorption, is rapidly converted to mercuric ions in the blood which can lead to renal
tubular damage.
When absorbed by way of inhalation, maximum concentration in brain tissue; acts mainly upon
cerebellum, temporal lobe, basal ganglia and corpus callosum.
In general

10. Metallic
Hg0
High lipophilicity
Absorption
~80%
Urine
~50%
Feces
~40%
Excretion
Hg0
Vapour

11. Inorganic
Salts
Hg2+
Hg+
Hg2+
Absorption
~10%
Excretion
Urine
~60%
Feces
~40%
High Watersolubility

12. Organic
Mercurials
High Liposolubility
Absorption
~90%
Excretion
Urine
~10%
Feces
~90%
Hg+ - CH3
Methyl Mercury

13. EXCRETION
Mainly through
• Kidney (urine)
• Liver (bile)
• Large intestines (feces)
Larger Quantity:
• Placental circulation
Others:
• Saliva
• Sweat
• Milk

14. ACUTE
POISONING

15. FATAL DOSE:
1-4 g Mercuric chloride
10-60 mg/kg Methyl mercury
10 mg/m³ Mercury vapor
1.5-2 g Mercurous chloride
7-10 g Mercuric oxide
Death may occur
within a few hours
but is usually delayed
for 3–5 days
FATAL PERIOD:

16. Acute poisoning occurs through....
INGESTION INHALATION INJECTION

17. SIGNS AND SYMPTOMS

18. ELEMENTAL MERCURY
Clinical
picture
INITIAL PHASE
INTERMEDIATE PHASE
LATE PHASE
Mental fume fever
Severe multisystem failure
Only CNS symptoms
Headache Cough Metallic taste Bronchitis Chemical pneumonitis Pulmonary edema Gingivostomatitis Coarse shakingSalivation
SUBCUTANEOUS OR INTRAMUSCULAR Abscess formation with ulceration, exuding tiny droplets of mercury
INTRAVENOUS Mercurialism – thrombophlebitis, granuloma formation, pulmonary embolism, repeated hemoptysis
• Deliberate suicidal gesture
• Misconception that it can enhance athletic or sexual performance
INJECTION
• Heating metal in a closed room
• Gold refining in an enclosed area
Nausea
Insomnia Ataxia Blurred visionParesis Delirium Polyneuropathy
CNS SYMPTOMS
INHALATION

19. GASTROINTESTINALSYSTEM
•Metallic taste
•Feeling of constriction in the throat
•Hoarse voice.
•Buccal cavity corroded, swollen and
mucous membrane appears grayish
white.
•Hot burning pain from the mouth to
the stomach and pain radiating over
the abdomen
•Followed by nausea, retching and
vomiting (grayish, slimy, mucoid
material with blood and shreds of
mucous membrane)
•Followed by diarrhea, often bloody with
tenesmus
RENALSYSTEM
•Oliguria
•Albuminuria
•Hematuria
•Ends in renal failure or nephritic
syndrome.
CARDIOVASCULARSYSTEM
•Hypertension
•Tachycardia
•Dyspnea
•Circulatory collapse.
IPHASE
INGESTION
INORGANIC MERCURIC SALTS

20. IIPHASE
If a person SURVIVES,
RENAL TUBULAR
NECROSIS• Polyuria
• Albuminuria
• Cylindruria
• Uremia
• Acidosis
MEMBRANOUS COLITIS
• Dysentery
• Ulceration of mucosa
• Hemorrhage
GLOSSITIS
ULCERATIVE GINGIVITIS
• Loosening of teeth
• Necrosis of the jaw
24–36Hours
2 – 3 Days 10 -14 Days RECOVERY

21. ORGANIC MERCURIALS
Latency Period
 1 week
Visual field constriction
Ataxia
Paresthesia
Dysarthria
Neuropathies Mental deterioration
Chorea
Hearing loss
DEATH

22. DIAGNOSIS
LEVELS IN BLOOD
3.6 μg/L 20 μg/LSymptoms develop
Atomic absorption spectrophotometer
excretion in feces and urine

23. Colonoscopy & X Ray
Ascending colon Cecum Ingestion Injection

24. TREATMENT

25. Removal from source of exposure
Provide Supplemental oxygen
Observe for the development of acute pneumonitis and
pulmonary edema
INHALATION

26. INGESTION
• Milk
• Egg white
• 5% albumin
B.A.L (Dimercaprol)Penicillamine Succimer
GASTRIC HIGH COLONIC
• 5% sodium formaldehyde
sulphoxylate
• 2 to 5% sodium bicarbonate
1:1000 solution of
sulphoxylate twice daily
• 100 mg/kg every 6 hours for 5
days
• 250 mg/kg four times a day
for 5 days
• 400 to 800 mg on first day, 200
to 400 mg on second and third
days, in divided doses every four
hours
• 100 to 200 mg in two divided
doses for 7 to 10 days
• Until urine level falls below 50μg
in a 24 hour specimen.
10 mg/kg
• every 8 hours for 5 days
• Every 12 hours for 2 weeks
Formation of protective
coating on mucosa
DEMULCENT
S
Renal damage
HEMODIALYSIS
LAVAGE
CHELATING AGENTS
Higher renal excretion of metal-agent complex

27. CHRONIC
POISONING
Hydrargyrism / Mercurialism

28. Chronic poisoning due to……
After effects of acute attack Continuous accidental
absorption by workers
Excessive therapeutic use External application for a long
time.

29. SIGNS AND SYMPTOMS

30. Tremors
Neuropsychiatric disturbances
Gingivostomatitis
TRIAD
CHRONIC
INHALATION
OF MERCURY VAPOUR

31. CHRONIC
INGESTION
Constant metallic taste
Gingivitis
Glossitis
Salivation
Loosening of teeth
Blue line in the gum
Anorexia
Anemia
Lymphocytosis
Jaundice
Uraemia
Restricted field of vision
Irritation of skin
Chronic inflammation of kidneys
Impairment of renal function
CNS toxicity
Impairment of
• Motor speed
• Memory
• Coordination.

32. CHARACTERISTIC FEATURES

33. TREMORS
Danbury tremors
Tremors
Hands << lips & tongue << arms & legs
Moderately coarse
Interspersed by jerky movements.
Hatter's shakes or
glass-blower's
shakes
Unable to dress himself, write legibly or
walk properly
Common in persons working in glass-
blowing and hat industries
Concussio
mercurialis
No activity

34. MERCURIAL ERETHISM
Refers to the
neuropsychiatric
effects of mercury
toxicity.
In persons working
with mercury in
mirror manufacturing
firms.
Anxiety
Depression
Shyness
Timidity
Irritability
Loss of confidence
Mental depression
Delusions
Hallucinations
Suicidal melancholia
Manic depressive psychosis
Emotional instability
Loss of memory
Insomnia

35. MERCURIALENTIS
Slit-lamp
examination
demonstrates a
malt-brown reflex
from the anterior
lens capsule.
Peculiar eye change due to exposure to the vapour
of mercury.
Brownish deposit of mercury through the cornea on
the anterior lens capsule - bilateral
There may be fine punctate opacities.
Visual blurring is often present, and sometimes
is concentric constriction of visual fields (“tunnel
vision”).

36. ACRODYNIAPink disease
• Mostly in children due to idiosyncratic hypersensitivity
reaction to repeated ingestion or contact with mercury
• The onset is insidious with anorexia, insomnia,
sweating, skin rash and photophobia.
• Hands and feet become puffy, pinkish, painful,
paraesthetic with peeling of skin.
• Teeth may be shed.

37. MINAMATA DISEASE
Chronic mercury intoxication caused by eating contaminated fish and
shellfish
• Paresthesia
• Narrowing of vision
• Dysarthria
• Diminution of hearing
• Amnesia
• Ataxia
• Staggering gait
• Weakness
• Emotional instability
• Some developed paralysis & are stuporous
Between 1953 and 1970, on the island of Kyushu around Minimata Bay
in Japan

38. DIAGNOSIS
LEVELS IN URINE
10-15μg/100 ml
Symptoms develop
excretion in feces and urine
20-100 μg/100 ml
Hair analysis by cold
vapour atomic
absorption
spectrometry

39. TREATMENT

40. CHELATION THERAPY
– BAL (British Anti Lewisite) - 100 mg by
deep IM, every 4 hours for 48 hours,
followed by 100 mg every 8 hours for 8 to
10 days. OR
– DMPS ( 2,3 DiMercapto Propane-1-
Sulfonate) - 5 mg/kg IV, or 6 infusions of
250 mg/day, followed by 100 mg orally
twice a day for 24 days.
OR
– DMSA (Meso 2,3 DiMercapto Succinic
Acid, or Succimer)
- 30 mg/kg/day orally for 5 days, followed
by 20 mg/day for 14 days.
– D-Penicillamine - 250 mg qid, for adults,
(20 mg/kg/day) for 5 to 10 days.
Removal from the
source of exposure.
Demulcent drinks
Saline purgatives

41. POSTMORTEM CHANGES

42. Emaciated – vomiting – purging
GIT Mucosa = Inflammation, congestion, coagulation, corrosion
o Mouth – necrotic - diffuse greyish white escharotic appearance
o Esophagus - corrugated and corroded
o Stomach - swollen - desquamation, haemorrhage, ulceration.
o Small intestine - necrosis - ulceration
o Caecum and large intestine - intense inflammation, ulceration
KIDNEYS = Acute proximal tubular damage - glomerular degeneration - glomerular nephritis
LIVER = Congested - cloudy swelling - fatty change
HEART = Fatty degeneration - subendocardial hemorrhage
INTERNAL
EXTERNAL:

43. THE CIRCUMSTANCES OF
POISONING

44. OCCUPATIONAL
EXPOSURE
(inorganic mercury)
• Mercury mines
• Chloroalkali plants
• Thermometer factories
• Health service
maintenance workers
(repairing broken
sphygmomanometers)
NONOCCUPATIONAL
EXPOSURE
• Dental amalgam
• Dietary intake
• Many foodstuffs
o Inorganic mercury
{lettuce, amaranth, water
spinach, cowpea and
rice}
o Organic mercury {fishes
e.G. Trout, pike and
tuna, etc.}
Homicidal And Suicidal Poisoning Is RARE.
ACCIDENTAL POISONING
• Diuretics
• Vaginal douches
• Dentistry
• Ingestion - antiseptic solutions - mercuric chloride/cyanide.
• Ingestion - sulphocyanide of mercury - Pharaoh's serpents
• Ingestion - mercurous chloride - teething powder -
ACRODYNIA
• Topical Application - Ammoniated mercury – bleaching
creams – Baby lotions

45. curious cluster of neurological symptoms
comprising paraesthesiae, narrowing of vision,
dysarthria, diminution of hearing, amnesia, ataxia,
staggering gait, weakness, and emotional
instability. Some developed paralysis and became
stuporous, and out of all the people afflicted nearly
nearly a hundred died. The condition came to be
known as the Minimata disease (Fig 9.18), and
intensive investigations pointed to one inescapable
conclusion: it was caused by consumption of fish
contaminated with methyl mercury, which
originated from a nearby vinyl chloride plant. The
most severely affected victims were actually infants
who had been exposed in utero.
In 1964, a similar outbreak of poisoning was
reported from another part of Japan: Niigata
along the Agano river. Forty three cases
were diagnosed as having the Minimata
disease out of whom six died.
In Iraq in 1971–72, when 500 people died out of
a total of 6530 victims due to consumption of
imported wheat and barley meant for sowing,
treated with methyl mercury. Nearly 95,000
tonnes of seed grain treated with methyl
mercury was baked into bread
ORGANIC MERCURIAL POISONING
TRAGEDIES

46. THANK YOU
BIBLIOGRAPHY
• The essentials of forensic medicine and toxicology - K
S Narayana Reddy
• Textbook of forensic medicine toxicology - Krishna
• Modern medical toxicology - V V Pillay
• Textbook of forensic medicine and toxicology –
Nagesh Kumar G Rao
• Concise textbook of forensic medicine and toxicology
– RK Sharma
• Review of forensic medicine and toxicology - Gautam
Biswas
• Mercury pollution in vegetables, grains and soils from
areas surrounding coal-fired power plants. {Rui Li, Han
Jing Ding, Weimin Fu, Lijun Gan & Yi Li , Scientific Reports volume 7, Article
number: 46545 (2017)}
• The Toxicology of Mercury Larry A. Broussard, PhD, DABCC,
FACB,1 Catherine A. Hammett-Stabler, PhD, DABCC, FACB,2 Ruth E.
Winecker, PhD,2,3 Jeri D. Ropero-Miller, PhD2
AYISHA MUFSIRA.S
III BNYS