Silent Killer: Unveiling the Deadly Effects of Arsenic Poisoning

Arsenic Poisoning-Metallic Arsenic is not poisonous, because it is not absorbed from intestines. The poisonous forms of arsenical compound as follows-

• Arsenic oxide/trioxide (Sankhya/Somalkhar)– most common
• Copper arsenite (Scheel’s green)
• Copper acetoarsenite (Paris green)
• Arsenic acid
• Sodium or Potassium arsenite
• Arsenic sulphide
• Arsenic trichloride (Butter of arsenic)
• Arsin
• Organic compound (Cacodylate, Atoxyl, acetarson, Salvarsan,Mepharsan etc.)

Character of Arsenic-

• No taste
• No smell
• Sparingly soluble in water
• When added to water it floats on the surface
• Sublimes on heating
• Smooth, heavy crystalline white powder

Uses-

• Fruit spray
• Sheep-dips
• Weed killer, Insecticide, Rat killer
• Fly paper
• Calico printing
• Taxidermy
• Wall paper and artificial flower
• Lather and timber preserving

Absorption– Orally (pentavalent) from stomach also, dermally (arsenite), inhalation (arsine)

Distribution– All tissues of the body. Mostly in bones and keratin tissue such as hairs, nails etc. In intermittent chronic poisoning, successive deposition of arsenic is seen in hair and nails. It appears in hair and nails within hour of ingestion. It does not cross BBB.

Excretion– Mainly through urine, but can also through bile, sweat, feces, milk and other secretion.  It appears in urine within half an hour of ingestion.

Tolerance– Chronic user as aphrodisiac may tolerate up to 0.3g. Such person is known as Arsenophagist

MECHANISM ACTION OF ARSENIC POISONING –

       (1)Arsenic   >      Sulphydyl groups of Pyruvate Kinase and other Phosphatases (in Mitochondria) >   Interferes cellular respiration i.e. glycolysis  Damage vascular endothelium  >  Dilatation of the vessels  > Increases vascular permeability  >Tissue edema & hemorrhage (specially in intestinal canal) > Hemorrhagic Diarrhea > Hypovolumic Shock > Death.

  (2)Arsenic >  Depression of CNS   > Coma  > Death.

  (3)Arsenic  > Depression of myocardium > Cardiogenic shock > Death.

FATAL DOSE– 0.1 to 0.2 g

FATAL PERIOD – o1 to 02 days

DAILY NORMAL INTAKE– 0.5 to 1 mg 

SYMPTOMS AND SIGNS OF ARSENIC POISONING:-

Fulminant Type-

 It occurs due to ingestion of massive doses (03 to 05 gm). The poison rapidly absorbed from the intestinal tract and causes massive dilatation of all capillaries and small arterioles specially in the splanchnic areas causes sudden marked fall of blood pressure followed by hypovolumic shock and death. It also depresses the action of heart muscles which also a cause of cardiogenic shock.

Gastroenteric Type-   This is common form. Starts half to one hour after ingestion. May be delayed for some hours if taken with food.

• Burning and colicky pain in the throat and abdomen
• Dysphagia
• Severe projectile continuous vomiting
• Intense thirst
• Severe involuntary  purging with tenesmus, pain and irritation around anus
• Stool is firstly dark color and bloody, later on colorless, odorless, rice-water type
• Acute circulatory failure
• Oliguria, hematuria, dysuria
• Headache, vertigo, tremor
• Hair loss and eruption in skin.

Narcotic Type-                                                                                                                              

• Giddiness
• Tenderness of muscles
• Delirium           >      Convulsion            >  Coma       >     Death
• Rarely complete paralysis of the muscles of the extremities

TREATMENT:

• Repeated stomach wash at intervals
• Demulcents prevent absorption
• Antidote- Freshly precipitated hydrated Ferric Oxide
• BAL- 200 to 400 mg in first day, 100 to 200 mg in second and third day, 50 to 100 mg for 7 to 10 days bd. DMSA or DMPS may be used instead of BAL. They are better. 
• Inj. Penicillamine- 250  to 500 mg qds.
• Purgatives- Castor oil or Magnesium Sulphate
• Cholera saline I/V to combat shock
• Antibiotics for preventing secondary infection.
• Analgesics and antispasmodic for controlling pain
• Hemodyalysis or exchange transfusion may required

POSTMORTEM FINDINGS OF ARSENIC POISONING:

External:

1. Signs of dehydration may be found
2. Rough, inelastic skin
3. Sunken eyes
4. Shrunken or emaciated body

Internal:

1. Stomach– Mucosa is swollen, edematous and red in patches or as a whole, especially at the pyloric area, greater curvature, posterior part and cardiac end. The mucosa appears as red velvet. Sometimes large sub mucous and sub peritoneal hemorrhage is seen. Arsenic particles may be seen on the sticky mucus covering the mucosa. Some erosion and ulceration may also be seen.
2. Intestines– Small intestines are flaccid and contain large flakes of mucus with very little fecal matter. Caecum and rectum show slight inflammation.
3. Liver, Kidneys and Spleen- are congested, enlarged and show cloudy swelling, rarely fatty changes. Glumerular nephrits is commonly seen in the kidneys.
4. Hemorrhages are seen in the abdominal organs, larynx, trachea and lungs.
5. Lungs-Are congested and subpleural ecchymoses.
6. Heart– Subendocardilal petechial hemorrhages of the ventricles are seen, which is also pathognomic.

D/D-

• Poisoning by phosphorus, barium or mercury.
• Heat stroke
• Acute infectious disease e.g. influenza
• Traumatic asphyxia

Special Features:

v  Arsenic in blood and liver is >1mg%

v  Sometimes arsenic penetrates through the walls of the stomach and appear in the liver and omentum.

v  If putrefaction takes place arsenic is seen as yellow streaks in the subperitoneal layer of the stomach and intestine. It is due to conversion of absorbed arsenic into sulphide.

v  It is found in bones, hairs, nails and skin after few years also

Arsenic is a popular Homicidal poison because

• It is cheap
• Easily available
• Colorless
• Odorless
• Tasteless
• Low lethal dose
• Can easily administered with food or drink
• Onset of symptoms are gradual
• Symptoms mimics a natural disease

Disadvantage as Homicidal poison because

• Sometime symptoms appear quickly
• It delays putrefaction
• Can be detected in highly decomposed body
• Can be detected in bones, hairs, nails after several years.

CHRONIC ARSENIC POISONING:

Sources:-

1. Drinking water
2. Adulterated food
3. Preserved food
4. Lather industries workers
5. Timber industries workers
6. Printing industries workers
7. Paint industries workers
8. Taxidermists

Pesticides industries workers

SYMPTOMS AND SIGNS OF CHRONIC ARSENIC POISONING-

Skin-

• Pigmentation (flexures, temple, eyelids, neck)- Rain-drop type
• Hyperkeratosis- (palm, soles, fingernails)-
• Aldrich-Mees lines in fingernails

Eyes– Congestion, watering and photoobia

GIT– Nausea, vomiting, abdominal cramps, diarrhea and salivation

CVS– CCF, dependant edema

Liver– Hepatomegaly, jaundice and cirrhosis of liver

Blood– Anemia, thrombocytopenia, bone marrow depression

Kidney– Chronic nephritis, oliguria, hematuria

CNS– Polyneuritis, paraesthesia, numbness, encephalopathy

TERATOGENIC– Can cause Lung and skin cancer, Leukemia

TREATMENT:-

• Removal of the patient from the source
• BAL or Penicillamine
• High protein diet, fresh vegetable
• Care of hands and feet
• Antibiotic if secondary infection occurs

PM FINDINGS:

• Emaciated, jaundiced, hyperpigmented, hyperkeratosis
• Stomach- Normal or signs of chronic gastritis
• Intestines- Dilated with thickened mucosa
• Liver- Fatty change or necrosis
• Kidney- Signs of tubular necrosis