corrosives, sulphuric acid poisoning, vitriolage, mechanism of action, classification of corrosives

1. 137
1830

2. Classification of Corrosive poisons and
Sulphuric acid poisoning

3. Corrosives - The definition:
 A corrosive is a substance that fixes, destroys and
erodes the surface with which it comes into contact.
 The word 'corrosion' is derived from the Latin
verb ’corrodere’, which means 'to gnaw', indicating
how these substances seem to 'gnaw' their way
through the flesh.

4. Classification of Corrosive poisons:
1.Mineral acids 2. Organic acids
-Sulphuric acid -Oxalic acid
-Nitric acid -Carbolic acid
-Hydrochloric acid -Acetic acid
-Salicylic acid
3. Vegetable acid 4. Alkalis
-Hydrocyanic acid - Caustic potash and soda
- Ammonium hydroxide

5. Mechanism of action of corrosives:
Any part of the body + corrosive substance
Extraction of water
Liberation of heat
Coagulation and precipitation of cellular proteins
Conversion of hemoglobin to hematin
Corrosion and destruction of tissues

6. Sulphuric acid
‘Oil of Vitriol’; ‘Battery acid’; ‘Oleum’
Physical appearance:
 Heavy, odorless, colorless, non-fuming, oily liquid.
 Has a tendency to carbonize organic substances.
 Hygroscopic; has great affinity for water and evolves
tremendous heat when mixed with it.

7. Uses:
 Industrial chemical
 Storage batteries and accumulators
 Pipe and drain cleaners
 Laboratory
Fatal dose: 10 to 15 ml
Fatal period: 12 to 24 hours

8. Clinical features:
 Corrosion of mucous membranes of mouth, throat,
esophagus.
 Epigastric pain spreads all over the abdomen and
thorax.
 Pharyngeal pain- the most common presenting
symptom.

9.  Teeth- chalky-white.
 Tongue- swollen, sodden and black.
 Abdomen- distended, very tender.
 Eyes are sunken and pupils dilated.

10. Dysarthria
Dysphagia
Retching
Vomiting
Hematemesis
Dehydration
Constipation
Tenesmus
Starvation
Thirst
Perforation of stomach
Chemical peritonitis
Stricture of
esophagus
and pylorus
Dysphagia,
infection
GIT- Signs and symptoms:
Severe burns in mouth, esophagus and stomach.
SHOCK AND DEATH

11. Respiratory signs:
Inflammatory edema of glottis or larynx
Dyspnoea
Suffocation
Death

12. Complications and The Cause of death:
1.Circulatory collapse.
2.Spasm or edema of glottis.
3.Collapse due to perforation of stomach.
4.Toxaemia.
5.Delayed death due to—
 hypostatic pneumonia
 secondary infection
 renal failure
 starvation due to stricture of the esophagus.

13. Treatment:
 Gastric lavage, activated charcoal and emetics-
contraindicated.
 Acid immediately diluted and neutralized in situ by-
- One-fourth litre of water or milk
- Milk of magnesia or lime water
- Aluminium hydroxide gel; within 30 minutes of
ingestion.
 Alkaline carbonates and bicarbonates-
contraindicated.

14.  Prednisolone- 60mg/day; to prevent esophageal
stricture and shock.
 A 3-4 cm mercury-filled bougie is passed daily if
stricture develops.
 Correct circulatory shock.
 Tracheostomy if there is oedema of the glottis.
 Concomitant prophylactic broad-spectrum
antibiotic use is recommended.

15.  No oral feed until endoscopy confirms the extent of
injury.
 Eye burns require copious irrigation with sodium
bicarbonate with the eyelids retracted for 10-15
minutes. A suspended i.v. bag that administers low
pressure irrigation is ideal.
 Laparotomy is required for patients with gastric
perforation and peritonitis.

16. Autopsy findings:
External:
 Evidence of acid corrosion and chemical burns with
brownish-black parchment like and corroded spots
are seen over the chin, cheek, neck and chest
resulting from trickling of the acid.
 Excoriation of lips.
 Corrosion of mucosa of mouth and tongue.
 Chalky-white teeth.

17. Internal:
Limited to the upper digestive tract and respiratory
system.
 Mucous membrane of esophagus inflamed,
swollen by edema and severe interstitial
hemorrhage present, even when corrosion is
absent.
 Greater part of the stomach converted into soft,
boggy, black mass that readily disintegrates on
touching. Blackened with peppery feel.

18.  The Small intestine shows evidence of irritation.
 Severe inflammation of the larynx and trachea.

20. Diagnosis:
Litmus test:
 The pH of the saliva tested to determine whether
the chemical ingested is an alkali or an acid.
 Fresh stains in clothing may be tested by adding a
few drops of sodium bicarbonate.
Production of an effervescence is indicative of an
acid stain.

21. Radiology:
 In view of the high rate of perfusion, water soluble
contrast agents are used for evaluation.
 Diffuse mottling of lung fields on X-ray when there
is inhalation of acid vapor.
 Chest and abdominal X-rays and routine laboratory
testing should be obtained to evaluate for
Aspiration,
Perforation and
Organ dysfunction.

22. Endoscopy:
 Used to document the site of injury and its severity.
 Better performed 12-14 hours after ingestion.
 The squamous epithelium of the esophagus is
relatively resistant to acid burns, while the
columnar epithelium of the stomach is very
susceptible.
Hence perforation of the stomach is more frequent
than that of the esophagus.

23. Medico-Legal aspects:
 Accidental poisoning results due to mistaking it
for glycerin or castor oil.
 In suicide.
 Rarely used in homicide.
 Taken internally or injected into the vagina as an
abortifacient.
 Vitriolage.

24. THE ACID-BATH MURDERER:
Have a body to get rid off? Talk to Haigh.
On 18th February 1949,
John George Haigh, self-professed
owner of a factory, induced an
early widow to accompany him
to his warehouse where he shot
her and then dumped her body
after removing some valuables, in a steel tank filled with
sulphuric acid.

25. •28 pounds of human body fat
•Three faceted gallstones
•Part of a left foot, not quite eroded
•Eighteen fragments of human bone
•Intact upper and lower dentures
•The handle of a red plastic bag
•A lipstick container
The remains were discovered by the police on
March 1st. By then, the body had been converted into
a sludgy, greasy material. Careful retrieval by the
forensic pathologist Prof. Keith Simpson yielded-

26. “BUT IF THERE ARE NO BODIES, HOW
CAN I BE CHARGED WITH MURDER?”

27. Thank you!