Федеральное государственное бюджетное учреждение науки
There are up to one hundred of anthropological investigations performed each year by the Laboratory of Osteology at the Lithuanian Institute of Forensic Medicine. The material for examination includes skeletal remains which are usually found by general public when caring out building excavations. However a discovery of sewer decomposed corpses on the earth's surface or in the water is also not uncommon.
When objects thought to be skeletal remains are found, one of the most difficult question need to be asked and where possible, answered is: "how long have they been dead and/or concealed?"
An investigation searching to resolve this problem involves the following steps:
visual inspection,
an investigation under a macroscope,
histological examination,
an evaluation of the bone surface and sections in the ultraviolet light.
1. An investigation of bones found
on the earth's surface or in the water
One investigating skeletal remains which have rest on the earth's surface or in the water for different time periods (of up to 1,5 years, from 1,5 to 3 years, from 3 to 5 years) can notice that most of the specimens belonging to a certain time group represent quite distinct features (table 1).
Table 1. Macroscopic and microscopic features observed on the surfaces and in the cross-sections of bones founded on earth surface or in the water.
No |
Observed features |
from 0,5 to 1,5 years |
from 1,5 to 3 years |
from 3 to 5 years |
Macroscopy |
||||
1. |
Adipocered soft tissues |
partial presence |
small remnants |
no |
2. |
Surface discoloration |
whitish-yellowish |
greyish-whitish,or yellow-brownish (soil contact) |
greyish, or whitish (on earth) |
3. |
Organic smell |
enamates |
no |
no |
4. |
Surface adipose soaking |
full or halfway |
islands rarely |
no |
5. |
Traces of erosion |
no |
no |
starting scarification |
Microscopy |
||||
6. |
Bones porous tissue¢ s filling with adiposed mass |
fully |
partially or parafin shaped |
no |
7. |
Blood vessels content |
blood |
blood |
seldom blood |
8. |
Haversian channels content |
empty |
empty |
empty or filled with adipose masses |
9. |
Bones structure changes in cross-section |
no |
no |
no |
10. |
Colour of the ultraviolet light fluorescent in cross-section |
non-fluorescent, or whitish-bluish line outern |
slightly bluish |
whitish blue, sometimes strong |
11. |
Rough weight |
heavy |
heavy |
lighter |
1.1. Bones features in the time period of up to 1,5 years
- there is a partial presence of adipocered soft tissues;
- the bones display a whitish-yellowish discoloration and emanate a foul organic smell;
- the macroscopic view of the cross-sections of the bones does not indicate distinct changes in the structure of long bones. The compact tissue is halfway or fully adipose-soaked, the long bone marrow cavity and skull vault porous tissue is fully filled with adipose mass,
- the microscopic examination of the bones slices reveals blood in the nutritional vessels and shows empty Haversian channels;
- in the ultraviolet light the cross-sections of the bones are non-fluorescent and only a whitish line of a bluish tint can be observed on the outer bones surface.
1.2. Bones features in the time period of 1,5-3 years
- only small patches of dried or curdled soft tissue remnants in the ligaments fixation places and natural cavities can be noticed.
- the parts of bones having had contact with soil usually present a greasy surface having dark yellow-brownish discoloration, microscopic examination of which shows no traces of erosion;
- the external aspects of bones which have been more or less influenced by environmental conditions look dry, porous, with traces of separate splits showing a greyish - whitish discoloration. There is no stratification of the external skull plate,
- the bone compact tissue is adipose-soaked, adipose wax masses are observed in the bone marrow cavities, in the skull vault porous tissue adipose wax masses are paraffin-shaped,
- histological examination reveals no changes of the bone structure, the blood in blood vessels and empty Haversian channels,
- the cross-section of the compact tissue is of a whitish color showing slightly bluish luminescence in the ultraviolet light.
1.3. Bones features in the time period of 3-5 years
- there is no remnants of ligaments or cartilages on the outer bones surface. In very rare cases tiny patches of soft tissues can be observed;
- bones are lighter in weight. The bones surface is dry, bleached with no adipose reflection representing deep, quite long infractions. The external skull plate demonstrates the signs of starting stratification;
- the skull vault of younger individuals gets deformed due to a partial separating of the bones sutures,
- there is no adipose wax masses in the long bone marrow cavities;
- microscopically bone structure indicates no changes, blood vessels seldom contain blood, Haversian channels are either empty or partially filled with adipose masses,
- in the ultraviolet light the bone compact tissue fluorescence with a rather strong whitish blue color.
2. An investigation of bones found in soil
Bones could remain in soil under different conditions - in dry sand (in a pine grove), in damp black soil (in a fir-grove) or in marshy soil, so it is rather complicated to monosemantically generalize burial time (table 2).
Table 2. Macroscopic and microscopic features observed on the surfaces and in the cross-sections of bones founded in the soil.
No |
Observed features |
from 1,5 to |
from 3 to |
from 8 to |
over 40-50 to 100 years |
Macroscopy |
|||||
1. |
Adipocered soft tissues |
small quantity |
a few ligaments and cartilagines |
no |
no |
2. |
Surface discoloration |
whitish- yellowish |
from whitish -yellowish, to yellowish- brownish |
from yellow to brownish |
from dark yellow to brown |
3. |
Organic smell |
enamates |
sometimes |
no |
no |
4. |
Surface adipose soaking |
distinct greasiness |
greasy |
no |
no |
5. |
Traces of erosion |
no |
onset of scarification |
scarification and separate infractions |
scarifications, infractions, stratifications |
Microscopy |
|||||
6. |
Bones porous tissue¢ s filling with adiposed mass |
partial |
no |
no |
empty, or con- tains remnant of blackish mass |
7. |
Blood vessels content |
blood |
empty, or seldom blood |
empty |
empty |
8. |
Haversian channels content |
empty |
empty, or partially filled with adipose mass |
partially, or fully filled with adipose mass |
empty |
9. |
Bones structure changes in cross-section |
no |
no |
no |
surface minera- lization till in 0,5-1,5mm depth |
10. |
Colour of the ultraviolet light fluorescent in cross-section |
no as rule |
whitish- bluish or violet-greyish |
brithly- violet |
bluish-violet, greyish-violet |
11. |
Rough weight |
heavy |
heavy |
heavy |
light in weight |
Note - Bones samples remained in soil over 15 to 40 years in our laboratory not investigated.
2.1. Bones features in the time period of up to 3 years
- there is a small quantity of soft tissues on bone surface which itself shows no noticeable changes, except distinct surface greasiness;
- the cross-sections of bones compact tissues are adipose-soaked, the blood vessels contain blood, the marrow cavities and porous tissues are filled with adipose masses,
- histologicaly blood vessels contain blood, Haversian channels seem to be empty,
- as a rule there is no fluorescence in this time interval.
2.2. Bones features in the time period from 3 to 8 years
- only few ligaments and cartilages can be observed on the bone surface which looks greasy with onset of scarifications;
- marrow cavities and the skull vault porous tissue contain remnants of adipose masses,
- the adipose-soaked patches in the cross-section of long bones can be still observed;
- microscopical investigation enables to detect the blood in vessels and adipose wax masses in Haversian channels;
- in the ultraviolet light bones give fluorescence with a whitish - bluish or violet-grayish color.
2.3. Bones features in the time period from 8 to 15 years
- bones are heavy, show no surface greasiness, the microscopic examination reveals scarifications, in some cases separate infractions can be observed on the surface, some areas indicate stratification of the external skull plate surface layer;
- in the cross-section of long bones compact tissues contain no adipose-soaked patches,
- there is no adipose masses in the long bone marrow cavity and the skull vault porous tissue,
- the external surface of compact tissue displays no signs of mineralization;
- histologicaly the blood vessels contain no blood, Haversian channels are partially or fully filled with adipose masses,
- the cross section the compact tissue brightly fluorescence with a violet color.
2.4. Bones features in the time period of more than 30-40 years
No investigations of such kind of bones has been carried out in the laboratory.
2.5. Bones features in the time period over 40-50 to 100 years
Such kind of bones usually having survived since the War#2 or the post-war period are submitted to the laboratory very often. The main features of them can be described as follows:
- the bones are light in weight, dry, the color varies from dark yellow to brownish or brown;
- the surface contains many scarifications and infractions, the stratification of the skull vault exterior plate is observed;
- the porous tissue and marrow cavities are empty or contain remnants of a blackish crumbling mass,
- in the cross-section the compact tissue in the depth of 0,5-1,5 mm is mineralized, whereas in deeper layers the bone structure is well preserved,
- microscopically the blood vessels contain no blood and Haversian channels look empty,
- in the ultraviolet light the compact tissue always fluorescence well with a bluish-violet, bright violet or greyish - violet color.
Final note
The mentioned data are only preliminary, especially when the bones have been found in the soil. It depends on the absence (as usually) of preliminary information concerning the sort of the soil from which the bones have been excavated.
Список литературы
