Drowning- Test

A i.e. Bone marrow of femur

D i.e. Diatoms in bone marrow

A i.e. Algae

B i.e. Diatoms has an extracellular coat composed of Mg

–   The extracellular coat of diatoms has silica and not magnesium

–    ‘Their cell walls are usually strongly impregnated with silica and contatain chlorophyll and diatomin, a brown pigment.’ ‘Diatoms secrete a hard siliceous outer box like skeleton called a frustule’-Reddy 24,h/315

–   Diatoms are a class of microscopic unicellular algae found suspended in most natural waters – Parikh

–    Diatoms are of medicolegal significance: Presence of diatoms in brain or bone marrow indicates antemortem inhalation of water

Diatoms present in water enter the lungs with inhaled water. Subsequently, only a live body with an intact circulation can transport diatoms from lungs to the brain or bone marrow.

Diatoms detected from bone marrow are thus indicative of antemortem drowning. The test is negative when dead bodies are thrown in water and dry drowning – Parikh

The current technique for isolation of diatoms involves acid digestion of tissue – commonly bone marrow, lung, blood or kidneys with subsequent centrifugation and washing – Parikh

Ans: C i.e. Drowning

Mode of death and findings

• Post-mortem findings of burns include heat hematoma (charring of skull), thermal fractures of the skull, pugilistic attitude, blisters, heat ruptures etc
• The ligature mark in the neck is the most important and specific sign of death from hanging
• The finding of similar diatoms in the water and in the body tissues is in favour of drowning

– The drowning fluid and the particles in it, e.g. diatoms and planktons, pass from the ruptured alveolar walls into the lymph channels and pulmonary veins and thus enter the left heart.

– Only a live body with circulation could transport diatoms from the lungs to the brain, bone marrow, liver and other viscera, and skeletal muscle.

Ans. Silica

Ans. Drowning

Ans. is ‘b’ i.e., Drowning

• Repeat from previous session. See explanation-2 of session-3.

Ans. is ‘b’ i.e., Chloride content of blood in drowning

• Gettler test estimates chloride content of blood from both sides of heart.
• It is done for drowning.
• Normally the chloride content is equal in the right and left chambers of the heart (600 mg/100 m1). In fresh water drowning due to hemodilution the chloride content is decreased and in salt water drowning due to hemoconcentration the chloride content is increased in left side of heart.
• A 25% difference in chloride is significant but the test is of doubtful value.