DROWNING

DROWNING

Definition –

Drowning is a form of violent asphyxiation where the respiratory passage is occupied by fluid i. e., water, due to submersion under water and inhalation of water. To be drowned, it is not necessary that the whole body should be under water. Submersion of mouth and nasal openings by any means is sufficient for that purpose.

In a classical case of drowning, full submersion does not occur all at a time. The mean specific gravity of the body is less than that of water. It is due to the buoyancy of the body that a person can float or swim on water.

Causes of drowning –

(a) For a swimmer exhaustion or other adversities.
(b) For a non-swimmer incapability to utilise the buoyancy of the body to keep the nose and mouth above the surface level of the water.

Process of drowning in a non-swimmer –

DROWNINGDue to the ignorance how to swim and due to panic and apprehension, the victim of drowning first swallows and inhales water, and thus the air in the lungs is gradually replaced by water. These increase the weight of the body which ultimately submerges totally under the water surface. When the paniky victim cries for help, a good amount of air from the lungs come out. In the attempt of inspiration, when some water comes in contact with the laryngeal opening, there is automatic cough reflex and thus a part of the reserve air from the lungs also comes out. Simultaneously, as the victim engulfs some water, the weight of the body further increases.. Ultimately the mean specific gravity of the body becomes more than that of the water which leads to final submersion.

Types of drowning –

Depending on different circumstances, effects and factors, we get the following types of drownings –

1. Dry drowning (type -1)
2. Wet drowning (type – II)
(a) Fresh water drowning (type – IIA)
(b) Salt water drowning (type – IIB)
3. Shallow water drowning
4. Immersion syndrome
5. Secondary drowning.

1. Dry drowning: Type I drowning –

In about 10% to 20% of deaths due to drowning no water is found in the lungs during the postmortem examination. These are the circumstances where death actually occurs due to submersion or drowning, yet the lungs remain dry or water-free. This may occur in two ways : (i) During first inhalation of water, there is severe laryngeal spasm which does not allow any water to enter the lungs though death occurs due to asphyxia due to laryngeal spasm in a circumstance of drowning, (ii) When death occurs due to vagal inhibition of heart before complete submersion of the body under the water, as it happens in case of immersion syndrome.

2. Wet drowning: Type II drowning –

In this variety, the water enters the lungs. The effects of water entering the lungs depend on, whether submersion has occurred in fresh water (type II – A) or it has occurred in salt water (type II -B).

(a) Type II – A drowning – When drowning occurs in fresh water and the water enters the lungs, then due to difference in the salinity between the inhaled fresh water and the blood, there is passage of water from the lungs to the circulation. As a result, the chloride level in the blood of the left side chambers of the heart decreases to almost its 50% value. There is haemodilution which ultimately causes haemolysis with resultant absolute and relative low count of R.B.C. and increase in the plasma potassium level and decrease in the plasma sodium level. As a result, not only there is increased load on the heart due to increased volume of the blood but the heart muscle also suffers from hypoxia and there is ventricular fibrillation. In fresh water drowning, there may be upto 72% increase in the total volume of the blood.

(b) Type II – B drowning – In salt water drowning, when water enters the lungs, due to high salinity of the inhaled water, water from the blood is drawn in the lungs. This causes pulmonary oedema, haemoconcentration, 30 – 40% increase in the level of chloride in the blood of the left side chambers of the heart, an overall increase in the plasma magnesium concentration, relative increase in the R.B.C. count of the blood and microscopically, crenated appearance of the R.B.C.s. There is hypoxia.

3. Shallow water drowning –

Alcoholics, epileptics, infants and children and unconscious persons may die due to drowning in shallow water, in a shallow pit or a drain. In shallow water drowning, the whole body need not be submerged. Submersion of face alone is sufficient to cause drowning if the mouth and the nose remains under the water. If shallow water drowning occurs in a drain then the debris and dirts present in the drain water will also be present in the lumen of the respiratory tract and in the stomach. Shallow water drowning cases are either accidental or homicidal.

4. Immersion syndrome –

This is a condition which is found in temperate and cold zones. Usually the young swimmers are the victims. When they dive in very cold water, they may suffer from vagal inhibition of the heart and die sudden death in water, even though they may be good swimmers.

5. Secondary drowning –

This is not drowning in the truest sense, but a complication or sequelae of drowning. After a few days of recovery from drowning, the victim may suffer from pulmonary infection and oedema. Ultimately the person may die due to asphyxia of pulmonary origin. Due to its aetiological background, such a development is termed as secondary drowning.

Causes of death due to drowning circumstances –

1. In case of dry drowning – (a) asphyxia due to, laryngeal spasm and (b) in case of vagal inhibition due to heart failure.

2. In case of wet drowning of type II-A variety – (a) ventricular fibrillation, (b) overloading of circulatory function due to upto 70% increase in the volume of circulating blood, (c) due to hypoxia of heart musculature, all leading to heart failure.
3. In case of type II-B variety, haemoconcentration, and pulmonary oedema leads to death by asphyxiation.
4. In case of immersion syndrome – vagal inhibition of heart.
5. In case of divers, head injury may also be the cause of death,
6. In case of sea water drowning – gnawing by aquatic animals like shark fish may also cause death.
7. In some cases, complications like subsequent infection and pulmonary oedema may be the cause.

Symptoms in drowning –

The subjective features in drowning are interesting and divergent from person to person, as narrated by some of the victims after being rescued and resuscitated. Some gave a feeling of dullness and total lethargy, though not unconscious. Some gave a painless feeling with memory of events which were of very remote past but interesting. Some visualized an imaginary family gathering around him while others described extreme pain and mental agony, as their experiences.

Treatment – When the subject is removed from water, artificial respiration may save his life. Holger Nielson method or Schaffer’s method may be tried. In any case, head should be at a lower level than chest.

Signs of submersion in a dead body removed from water –

Most of these signs are not specific of death due to drowning and are rather signs of submersion of the body under water for some period.

External signs –

1. When freshly removed from water, the body and the clothes will be wet. Irrespective of the time passed after recovery of the body from the water, there will be sand and mud stain on the body, hair and clothes. This finding is not specific of antemortem drowning or death due to drowning.

2. Development of cutis anserina (goose skin like appearance of the surface of the body) is another non-specific finding which also does not tell about the antemortem or post-mortem nature of drowning. This condition develops due to contraction of the erector pilae muscles of the skin occurring due to contact of the body with the cold water. It also occurs in all dead bodies during the state of rigor mortis of the muscle of the skin. Cutis anserina is not appreciable when decomposition of the dead body starts.

3. Retraction of the scrotum and penis in males is another non-specific finding, which occurs due to submersion, whether before or after death.

4. Changes in the skin of the palm and sole, like that which occurs in a washer-woman is yet another non-specific sign of submersion of a body under water for some hours which has no relationship specifically with antemortem or postmortem drowning. The skin of the palms and soles appear bleached, sodden, corrugated and thickened.

5. Presence of mud, sand, gravel and weed in the hand, in a state of cadaveric spasm is one of the confirmatory signs of death due to drowning, because the cadaveric spasm of the hands indicate the last work of the person which he performed during the process of his death. Presence of sand, weed etc. in the hand in that state, indicates that, just before death he tried to grab the soil at the bottom of the water. This means that at the time of death he was submerged under the water.

6. Presence of copious fine white froth near the mouth and the nasal opening is another vital finding in a case of death due to drowning. It occurs due to the churning effect of the air in the alveoli, the water inhaled and the mucus secretion from the respiratory tract wall. The churning effect results from the violent effort for respiration. Another feature of this frothing is that, it continues to come out for a considerable period, even if wiped out again and again. Continuous frothing is a very very strong finding in support of death due to drowning but is not absolutely confirmatory, as it may occur in those cases where death is preceded by pulmonary edema.

7. Presence of sand and mud in the nail beds, though not in the tight grip of cadaveric spasm, is another important finding in support of antemortem drowning and bears weight in this respect, though not as forceful as the cadaveric spasm.

8. Water may be present in the middle ear. It is not a very important finding.

9. Suffused and congested conjunctiva is another external finding of antemortem drowning which also carry reasonable weight towards antemortem phenomenon of the drowning.

10. Distribution of postmortem staining in a body removed from water is somewhat different than in other dead bodies and is usually found over the head, face and neck. The head being heavier than other body parts, assumes lowest level when the body floats on water. However, when the body continuously rolls over flowing water, postmortem staining may not appear at all.

11. Sand and mud may be present inside the mouth cavity and the nose, which is not very much significant regarding the cause of death.

12. A dead body recovered from a pond or river may bear post mortem injury due to eating by fish or other aquatic animals or due to impact with some projecting substances.

13. Antemortem injury over the head in case of diver whose dead body has been recovered from a diving pool is significant as a sign of death due to the process of drowning or diving.

14. It must be remembered that a dead body though is fresh when removed from the water, may be in an advanced state of decomposition when postmortem examination is performed by the autopsy surgeon. This is because a submerged dead body decomposes very rapidly, once the body is removed from the water, though while in water the rate of decomposition is generally slow.

Internal findings –

1. As discussed under the heading of external findings the mouth cavity will show presence of sand, mud etc. which are not of much significance.

2. Sand, mud or weed may be present in the oesophagus which is also not very much significant in support of death due to drowning.

3. The lumen of the larynx, trachea, bronchus and bronchioles show presence of fine froth mixed with sand and mud. This is a very important sign of death due to drowning. Presence of sand and mud in the lower respiratory tract is more important than their presence in the upper respiratory tract.

4. The lungs are voluminous, oedematous, have balloon like appearance with marks of indentation over the surface by ribs. The lungs pit on pressure. When incised, the cut surfaces ooze frothy thin fluid blood. When the person submerges consciously, violent respiratory effort may cause rupture of the alveolar walls, particularly underlining the pleura near the lower margins. The ruptured large alveolar spaces contain watery, thin, haemolysed blood, some amount of air. This change in the lung is known as “emphysema aquosum” change. This change is more commonly seen at the undersurface of pleura, near the margins of lower lobes which is popular as paltauf’s sign or paltauf’s haemorrhage. But when death occurs before total submersion or when the person goes under the water in an unconscious state, i.e., when there is no violent effort for respiration, there may not be any sign of emphysema aquosum. Instead, some water may enter the lung’s bed passively, causing passive oedema of the lungs. This condition is known as “oedema aquosum”. In some cases where death occurs due to laryngeal spasm and the body is recovered soon after death, the lungs may not contain water (dry drowning), in contrast to the aquosum conditions of the lungs (wet drowning). An interesting negative finding in case of wet drowning is absence of Tardieu’s spots. This is due to leakage of water in the subpleural space.

5. The stomach may show presence of water, sand, mud and weed. This is another diagnostic feature of death due to drowning, because their presence in the stomach indicates reflex swallowing of water etc. during the process of submersion and inhalation of water.

6. Presence of water, sand etc. in the upper part of the intestine is diagnostic of death due to drowning, because passing of these substances through the pylorus needs antemortem process of peristaltic movement and opening of the pyloric sphincter.

7. The blood is thick in case of death due to drowning in salt water (wet drowning type – II – B), and is thin due to haemolysis in case of drowning in fresh water (wet drowning type – II- A).

8. Laboratory findings –

(a) Detection of diatoms in some remote organs and tissues including brain and bone marrow. This is one of the most dependable signs of death due to drowning but there are falacies.

(b) Blood chemistry – The chloride level in blood of both side chambers of the heart is almost equal. According to Gettler, in case of fresh water drowning, haemodilution occurs in the right side chambers of the heart early and for this the chloride value of the blood on the right side chambers may come down to the 50% of the normal value of 600 mgm/100 ml. Conversely, in salt water drowning, there is haemoconcentration which affects the left side chambers of the heart first and as a result there is increase in the level of chloride in the blood of the left side chambers of the heart by 30% to 40%.

Apart from the chloride level of the blood of both side chambers of the heart, certain other chemical changes occur in the blood. In case of fresh water drowning there is haemodilution and haemolysis which causes increase in the potassium level of blood plasma and decrease in the plasma sodium level. In salt water drowning, there is haemoconcentration and there is increased magnesium level of the blood.

(c) Microscopic changes in the blood – In fresh water drowning there is both haemo- dilution and haemolysis which leads to both absolute and relative low count of the R. B. C. In salt water drowning, there is haemo- concentration which causes relative increase in the R. B. C. count. The R.B.C.s shrink and appear crenated.

The findings concerning the chemical changes in the blood definitely has some value. But the study of the chloride level in the blood of both side chambers is useless, if the deceased had a patent foramen ovale or some ventricular septal defect or if drowning has occurred in water with salinity equal to that of blood. Study of blood chemistry in drowning cases becomes meaningless altogether, if decomposition has reached advanced state, because decomposition as such alters the blood chemical levels to a great extent.

DIATOMS

These are unicellular algae which have inert silicon coating around them. These are present in all natural water sources, more abundantly in pond water or in a lagoon, or where the water is stagnant. They are less frequent in streams or in rivers where the water is frequently polluted by chemicals and industrial refuge.

When a drowning person inhales water and when the alveoli get distended with water and air, the alveolar walls may get ruptured exposing the capillaries which are also ruptured alongwith. The water from the alveolar sacs along with diatoms it contains, enters the circulation and are carried to distant organs and tissues. Hence, in a body removed from water, if diatoms can be demonstrated in the tissues of some distant organs (distant from the lungs and the body surface, to exclude the chance of contamination of the tissue by surface diatoms), then it goes strongly in support of death due to drowning. There are of course certain falacies of the presence of diatoms in the tissue.

Test for presence of diatoms –

1. By histological examination diatoms can be demonstrated in the lungs or rarely in some other tissue, provided that plenty of diatoms were present in the submerging water and a good number of them entered in the circulation.

2. Diatoms can be demonstrated, alternatively and comparatively more easily, by acid digestion of the of bone marrow (considered most suitable for collection of contamination-free sample of tissue and for most satisfactory interpretation), brain tissue or tissue from other organs.

The procedure –

Collection of non-contaminated bone marrow – The femur is the bone of choice. About 3 cm. x 2 cm area is chipped out after marginal sawing. The bone marrow is scooped out. 5-10 gms. of bone marrow is subjected to 10 -12 hour’s acid digestion in a mixture of 10 ml. of concentrated nitric acid and 0.5 ml of conc. sulphuric acid. Sulphuric acid carbonises the organic substance and hence the fluid is decolourised by sodium nitrate. Then to reduce the acidity of the fluid a little alkaline solution is added for a very short period. The fluid is repeatedly washed by distilled water by centrifugation. . The residue is dried on a micro-slide and mounted with media of high refractive index. One or more than one type of diatoms may be seen under the high power observation.

Alternatively, diatom test can be performed by dealing the tissue with conc. nitric acid alone and then observing under the high power observation of a microscope.

Value and falacy of diatom test –

Along with test of the tissue for diatoms, a sample of the water from which the body has been recovered, should be subjected to control test. If similar type of diatoms are not available in both the test sample of the tissue and the sample of water for control test or if diatom is only present in the tissue then it can be concluded that diatom entered the body tissue of the victim during the usual process of drinking water which contained diatoms. On the other hand, diatoms may not be observed in the tissue, even if drowning was antemortem and the water contained diatom. If diatoms are present in both test sample of tissue and control sample of water, then it is strongly presumed that drowning was antemortem in nature and occurred in that water. But still it is not conclusive in all cases. Even if the drowning was not antemortem in nature, similar diatom may be present in both the test sample and the control sample, if the victim was habituated to drink water from the same source during his/her life. This is because when a person drinks water a little of the water may trickle down the larynx and trachea etc. and may reach the lungs bed and through some weak point of the alveolar wails may enter the circulation and carried away to distant organs.

Inspite of chances of falacy, if similar diatoms are available, both in the tissue and the water then, that acts as a strong evidence of death due to drowning.

Medicolegal aspects of drowning or submersion of a body in water or questions which arise after removal of a dead body from water –

The following medicolegal questions may arise in connection with such a case.

1. Whether drowning was antemortem or postmortem.
2. If drowning was antemortem what was the precise cause of death ?
3. What was the nature of drowning, suicidal, homicidal or accidental ?
4. What is the time of death and when did the submersion occur ?
5. Was any other offence involved in the case ?
6. If the body is unidentified then establishment of the identity becomes an important step of investigation.
7. If the body has been recovered from a river, then it is necessary to know the actual place of drowning.

1. Whether drowning was antemortem or postmortem in nature –

Of all the postmortem findings available in a dead body, recovered from water, only some external and internal findings and some laboratory findings focus light on whether drowning was antemortem or postmortem. These are –

a) Cadaveric spasm of the hands with presence of sand, mud, weed etc. in the grip.
b) Copious, white fine froth through the nose and mouth.
c) Presence of similar froth along with sand, mud etc., in the lumen of the whole of the respiratory tract.
d) Voluminous lungs, like balloons, with indentation or presence of marks of ribs on the surface; discharge of copious frothy fluid blood from the cut surface; emphysema aquosum change; presence of thin haemolysed fluid blood in the spaces at the undersurface of the pleura on the lower lobes and at the interfaces of the lobes and absence of tardieu’s spots are the important features of antemortem drowning deaths.
e) Presence of water, sand, mud and weed in the stomach and the upper part of the small intestine.
f) Presence of diatoms in the distant organs or tissue, similar to those present in the water where the body of the victim was submerged.
g) Difference in the chloride levels in the blood of both side chambers of the heart.
h) Changes in the blood in addition to the above, like haemoconcentration, increased plasma magnesium level, relative increase in the R.B.C. count, about 40% decrease in the blood volume, crenated appearance of the R.B.C.s under the microscope (salt water drowning) and, increased blood volume (even upto 70%) due to haemodilution, haemolysis with absolute and relative decrease in R.B.C. count, increased potassium level and decreased sodium level in the plasma (in case of fresh water drowning).

If death was not due to drowning, then all the above findings will be absent in the dead body and the actual cause of death may be present.

In case of dry drowning, it is very difficult to say if death occurred due to drowning, because almost all the reliable signs of death due to drowning including the laboratory tests are those of wet drowning. Hence, in dry drowning, circumstantial evidences become important to come to the conclusion whether death was due to submersion under water.

2. If drowning was antemortem then what was the precise cause of death.

To know the precise cause of death in a circumstance of drowning, the following points must be given due consideration.

(a) If from the circumstance (e.g. from dependable eye witness) it becomes evident that death was due to drowning and even then, if the internal and laboratory findings are negative, then the natural conclusion should be that death was due to dry drowning, either due to laryngeal spasm or due to vagal inhibition. In the former, signs of asphyxia should be quite markable with occasional presence of water, sand, mud etc. inside mouth, nose, stomach and intestine and in the latter, though the splanchnic vessels will be congested, signs of circulatory collapse may be noticed and the signs of asphyxia will not be much prominent.

(b) If it is a case of wet drowning and if there are prominent signs of asphyxia, extreme degree pulmonary oedema, relevant changes in the blood in support of salt water drowning with history of drowning in salt water and presence of diatom in different tissues, then death can be said to have occurred due to asphyxia due to drowning in salt water.

(c) If on the other hand, it is a case of wet drowning (with evidence of water etc. in lung) with internal and laboratory findings in support of drowning in fresh water, then the cause of death should be circulatory failure due to overloading of the heart due to haemodilution, or ventricular fibrillation due to haemolysis or due to suboxic state of the heart.

(d) If there is antemortem head injury and if there is a history of diving, then the traumatic findings will be sufficient to know the precise cause of death. Similarly, if death has occurred due to certain other injuries after submersion, then that also should not create any problem in coming to the proper diagnosis.

3. What was the nature of the drowning, was it suicidal, homicidal or accidental ?

Accidental drowning – Most of the drowning deaths are accidental in nature. Accidental drowning deaths occur in the following circumstances.

a) For a non-swimmer – accidental fall in deep water.
b) Fow swimmers, exhaustion due to prolonged swim, bathing during high tide, by being caught in an under-current in a river.
c) Circumstances of bout capsize, ship wreck etc.
d) Fall of a bus or a train down, from a river bridge.
e) While an intoxicated or epileptic person takes bath in a river or a pond.
f) In circumstances of natural calamities like flood or cyclone.
g) Getting electrocuted by the electrical heating system of a bath tub.
h) Divers diving in a shallow pool.
i) By being attacked by an aquatic animal like shark or crocodile.
j) Precipitated labour in lavatory pan or while bathing, may cause accidental drowning death of the new born infant.
k) Accidental drowning death may also occur to a new born due to inhalation of amniotic fluid if the membrane remains intact.

For proper diagnosis of accidental drowning cases circumstantial evidences are very important. The cause of death in (g), (h), (i) is not exactly inhalation of water.

Suicidal drowning deaths have the following features –

a) It is a common method of committing suicide by the women-folk in the rural side.
b) If the person is a non-swimmer, then he or she simply jumps from a place of height in deep water.
c) If he or she is a swimmer, then he or she makes certain preparations to be sure that the attempt will not fail.
 i) Before jumping in water the hands and legs may be tied, so that, swimming will not be possible.
ii) Some heavy weight may be tied with the body, so that, very quickly the person goes under water.

d) In domestic environment inside the bathroom the suicide makes such arrangements with the water heating system of the bath tub that, he either gets electrocuted or drowns, to die, the process of drowning here being facilitated by electrocution.
e) In many cases, the suicide, failing in some other method commits suicide by drowning. In such cases during post-mortem examination of the dead body, some non-fatal injuries may be found on the approachable parts of the body or some suicidal poison may be present in the stomach and the viscera.

In all doubtful cases motive for suicide should be identified.

Homicidal drowning – Homicidal drowning deaths are not very common, but do occur. Different possible circumstances are –

a) Forceful drowning of an adult swimmer is a difficult process but may be caused –
i) When number of assailants are more than one.
ii) When the victim has been made unconscious by injury or drug.
iii) When the hands and feet of the victim are tied before pushing him into the water.
iv) When the head of the victim is forcefully dipped in water.

b) When the victim is a non-swimmer and is deliberately pushed into deep water, all of a sudden without his knowledge.
c) The victim may be packed in a gunny bag with his mouth tied and then thrown into water.
d) As in case of suicide, the electrical heating system of a bath tub may be so arranged that, the victim unaware of this manipulation, while in the bath tub may get electrocuted and die as a result of electrocution or drowning.
e) Occasionally unwanted newborn infants are thrown in water.
f) When a person is taking bath in a tub he or she can be easily drowned by pushing the head down in water or pulling the victim with her legs.

(In the “bride of the bath” case a person after marriage used to make life insurance policy in the name of the bride. Then the bride was used to be killed in this method in the bath tub inside the bathroom, in a ”playful mood”. In the third occasion he could be brought to the book).

4. What was the time of death and when did the submersion occur ?

This is not always an easy problem to be solved in case of death due to drowning or in case of a dead body recovered from water. The changes which occur in a dead body after death comes late in a submerged dead body. That alone would have not created much problem for the autopsy surgeon. But the real problem lies in the fact that, once the dead body is lifted out of water, the process of these changes, particularly the process of decomposition progresses very rapidly imposing two levels for consideration for ascertaining the time of death, one for the period the body was in water and the other, after the body was removed from water. Added to the problem is the fact that not in all cases of dead bodies recovered from water, death occur in water. In many cases dead bodies may be disposed off in water. Hence, the doctor while giving due consideration to ascertain the time of death should keep it in mind that, after death the body might had been left in air for some time, then for sometime it remained submerged in water and lastly, after recovery from water, it again passed some period in air.

It is for these reasons that, in case of bodies recovered from water, to ascertain the time of death, in addition to physical changes in the body, the doctor should also take into account some other factors like the stomach content and the findings which help to say for what period the body remained in water.

A rough idea about the period of submersion of the body in water can be formed from the following changes –

 i) Wrinkling of the skin starts by about half an hour after submersion and this is well-formed after about an hour.
ii) Bleaching and corrugation of the skin occurs by about 8-12 hours after submersion.
iii) The body temperature comes down to that of the water by about 14 hours after submersion when submersion is the cause of death or when the body is disposed off in water immediately after death. The rate of cooling of the dead body in water is roughly twice as that in air.
iv) Floating of the dead body, in our country, in summer, occurs by about 24 hours after drowning or submersion. In winter, this time in our country is 2 – 3 days.

5. Was any other offence involved in the case ?

In one of the cases of the present author, a woman was first raped by the side of a river and then drowned to death by forcefully dipping the head under the water. In another case, dissected parts of more than one dead body were recovered from a lake. Findings on the body parts were very much suggestive that, clandestine training on human anatomy were being undertaken, may be somewhere in the city of Calcutta.

6. If the dead body recovered from water is an un-identified one, then establishment of the identity of the deceased is an important step for proper investigation. In many cases, due to extreme decomposition of the dead bodies or mutilation by the aquatic animals or when recovered from a river the chance that the body might have floated a long distance, establishment of identity may require much effort. The facial appearance, the complexion and some other features may get totally distorted. In such cases steps to identify the person should proceed in the same line as in case of identification of a highly decomposed dead body or a mutilated dead body. The wearing apparels, a few pocket articles, certain body peculiarities, deformities, tattoo marks, all may still help identification. Fingerprints may also be procured. Sex, age, race should not create much problem as these can be known from the bones and teeth even if the soft tissues have been totally or to a great extent destroyed. Teeth may give certain additional informations for identification. Superimposition technique may be used, if the skull bone is available and if the life-time photograph of a doubtful missing person is also available.

7. If the body has been removed from a river, then it is necessary to know the actual place of drowning, because in such a case it is possible that the dead body might have floated down for several miles before detection and removal. If the actual place of drowning cannot be known, then the identity of the individual and other legal issues with the death may not be solved. In case of a river, it may not always be very easy to locate the actual place of drowning. The best way to do that, is to undertake the tedious job to study the diatoms of different parts of the river, at least of the possible parts where the person might have actually drowned, and to compare them morphologically with the diatoms identified in different organs of the victim. But one may question the usefulness of such an elaborate study, when it is known that, even in known cases of drowning, diatoms can be detected from the tissue of the body in only about 10% of all cases.