Ethanol

Ethanol is present in the following beverages:

1. Malted liqors (beer)
2. Wines (light claret cider)
3. Fortified port
4. Spirit (rum, gin and whisky)

Pure ethanol is transparent, colorless, volatile liquid having characteristic spirituous odor with burning taste. It boils at 173° F It burns with blue smokeless flame

Uses
It is used as a solvent for resins, volatile oil and Bromine.

Signs and Symptoms

1. Acute Alcohol Poisoning
Stage I
Stage of Excitement (Blood alcohol levels are between 50-150 mg)

1. Talkative
2. Sense of well being
3. Over consciousness
4. Defective speech and movement
5. Increased confidence and lack of self-control
6. Arguments and quarrels with people
7. Face flushed and conjunctiva congested
8. Increased sexual desire
9. Error of judgment
10. Lack of co-ordination
11. Person becomes self iritic
12. When blood level reaches 150 mg %, person is debarred to drive a vehicle

Stage II
Stage of stupor (Blood alcohol level is between 150 – 300 mg)

1. Total in coordination
2. Staggering gait
3. Lack of concentration
4. Incoherent speech. Error of judgement
5. Dilated pupils
6. Slurred speech
7. Sluggish reaction to light
8. Muscular incoordination
9. Patient becomes dull, apathetic and sleepy
10. Pulse rapid and bounding
11. Positional nystagmus or alcohol gaze nystagmus. There are jerky movements of eyeball in the direction of gaze independent to the position of eye.
12. Nausea and vomiting leading to sleep and wakes up with heavy headache

Stage III
Stage of coma: (Blood alcohol levels are between 300-500 mg)

1. Coma: Giddiness which may deepen into coma and patient wakes up from coma with severe headache nausea and depression.
2. Pulse: Pulse is weak and thready
3. Pupils: Pupils are contracted
4. M C Ewan’s sign: Contracted pupil which starts dilating when stimulation is applied over skin only, to become contracted again.
5. Death is due to cerebral hypoxia and respiratory failure.

Treatment

1. Stomach wash
2. Hot tea or coffee with glucose should be given to drink so that hypoglycemia can be treated.
3. Hot douches or cold bath should be given as the state demands.
4. Prevents acidosis.
5. Symptomatic treatment should be given.

Post-mortem Appearances

1. Smell of alcohol from inner organs.
2. Mucus membranes of all internal organs congested.
3. Visceras in this type of poisoning are to be preserved in saturated solution of Sodium chloride.

2. Chronic Alcohol Poisoning

Drunkeness: This is a condition which occurs in a person who is so much under influence of alcohol that he has lost control over his faculties to such an extent so as to render him unable to execute safely the occupations in which he was engaged at the material moment.

Signs and Symptoms

1. Loss of general health
2. Insomnia
3. Nausea, vomiting and anorexia
4. Loss of memory
5. Jaundice
6. Poor judgement
7. Generalized anasarca
   • Hypoproteinemia
   • Peripheral neuritis and dementia during the last stage
   • Other significant symptoms:
8. Delirium tremens: Due to long continued action of poison in the brain
9. Alcoholic polyneuritis with Karsakoff’s psychosis c. Alcoholic paronia d. Alcoholic hallucinosis
   
   Delirium Tremens: This may occur in chronic alcoholics under the following circumstances:

1. A temporary alcoholic excess in case of habitual drunkards.
2. A sudden withdrawal of alcohol in a habitual drunkard
3. Chronic alcoholics suffering from shock after receiving injury, such as fracture of a bone or from acute disease like pneumonia, influenza and erysipelas, etc. may also develop delirium tremens. The condition is characterized by:
   1. Disorientation in respect to time and place
   2. Delirium
   3. Delusions or hallucination of sight or hearing
   4. Tremors and restlessness
   5. Loss of memory and insomnia
   6. Violent tendencies and tendency to commit suicide or homicide.

Legally delirium tremens is considered as unsoundness of mind and not intoxication. Hence, he will not be held responsible for any criminal act during the phase.

Treatment
Psychoanalysis and therapy.

Post-mortem Findings

1. Rigor mortis lasts longer. Gastric mucus membrane shows a deep reddish-brown patches of congestion or effusion.
2. Liver fatty degeneration and cirrhotic changes.
3. Heart is dilated and shows fatty degeneration. Blood is in fluid state and comparatively dark.
4. Pupils are dilated.
5. Kidneys show granular degenrations.
6. Methyl alcohol.

Methanol (Methyl Alcohol Or Wood Alcohol)

Physical Appearance
Colourless, volatile liquid with characteristic odor.

Uses
Methanol is widely used as a solvent and is present as a constituent of :

1. Antifreeze agents
2. Shellac
3. Paints
4. Paint removers
5. Varnishes, etc.
6. It is also frequently used to denature ethanol, i.e. make it unfit for consumption.

Mode of Action

Toxicity results from accumulation of two of its metabolites: formaldehyde and formic acid. The latter is the main culprit and is responsible for a severe metabolic acidosis apart from other deleterious effects.

Fatal Dose : 60-25 ml
Fatal Period : 1-3 ml

Signs and Symptoms
There may be a delay of 12 to 24 hours after ingestion.

1. CNS: Headache, neck stiffness, vertigo, confusion and coma.
2. Eye: Mydriasis, blurred vision, photophobia, optic neuritis, retinal edema and blindness.
3. GIT: Abdominal pain, vomiting and acute pancreatitis etc.
4. Other systems: Acute tubular necrosis of kidney, profound metabolic acidosis, (producing deep, noisy respiration referred to as Kussmaul respiration), hemolytic anemia, etc.

Treatment

1. Stomach wash should be done (with sodium bicarbonate) or induction of emesis. Either of these procedures is to be undertaken only within 2 to 4 hours of ingestion.
2. Peritoneal wash or hemodialysis.
3. Ethanol is the antidote for methanol since it blocks the formation of formaldehyde and formic acid by its preferential affinity for alcohol dehydrogenase. It is preferably given as an I.V. in 10% solution starting with a dose of around 500 ml given as an infusion and repeating as required (until the blood methanol level falls below 25 mg%). Oral administration of ethanol is undesirable.
4. Recently, a new antidote for methanol has been introduced called – 4 methyl pyrazole, which is said to be more efficacious than ethanol.
5. Sodium bicarbonate I.V. to correct metabolic acidosis.
6. Supportive measures.

Post-mortem Findings

Post mortem appearances are essentially similar to that seen in ethanol poisoning. Cyanosis, particularly of the upper parts of the body is very prominent. Liver and kidneys show toxic damage. Lungs may reveal edema, emphysema and desquamation of alveolar epithelium. Eyes may show optic atrophy and retinal edema. Viscera must be preserved in standard solution of sodium chloride and not rectified spirit, as in the case of all other alcohols.

Medico-legal Importance

Most of the cases of methanol ingestion are accidental arising out of either an alcoholic deprived of ethanol for any reason, consuming methanol containing products or because of intentional adulteration of ethanol (especially arrack) resulting in mass deaths. The latter are referred to as “liquor tragedies” and are reported in Indian newspapers at regular intervals from various parts of the country, e.g. Suryapet (Andhra Pradesh) in 1973, Agra in 1974, Vypeen (Kerala) in 1980 and in Delhi in 1991 etc. Suicidal cases involving methanol are uncommon.

Reference: A Handbook of Forensic Medicine and Toxicology by Dr Madona Joseph & Dr Harpreet Kaur