Upload
others
View
0
Download
0
Embed Size (px)
Citation preview
Dr Tim Thompson RFPLecturer in Forensic Anthropology
Anatomy & Forensic Anthropology, School of Life Sciences, University of [email protected] www.tjuthompson.com
Heat-induced Changes tothe Human Body and theImplications for Positive
Identification
Contents
1. Burned Human Remains andForensic Anthropology
2. General Heat-induced Changes in theHuman Body
1. The Soft Tissues2. The Hard Tissues
3. The Implications for HumanIdentification
4. Conclusions
Attitudes in Anthropology
I would straight away place on record my consideredopinion, based on experience, that cremated remains
of human bones in burial urns are almost alwaysdevoid of any anthropological interest … From an
anthropological point of view, therefore, these bonesare of no scientific value, and I consider that nothing
is lost if they are neither submitted to nor preserved inthe Museum.
Professor CM FurstChief Inspector of Antiquities in Stockholm, 1930s
We are not starting from a happy place…
Contexts Surrounding Burned Remains
Anthropological Interest (archaeological, enthnographic, forensic & medico-legal)
The Story So Far…
Limited understanding due to lack of coherent, continuous research
McKinley, J.I. 1993 Bone Fragment Size andWeights of Bone frm Modern British Cremations andthe Implications for the Interpretation ofArchaeological Cremations. International Journal ofOsteoarchaeology 3: 283-287.
McKinley, J.I. 1994 Bone Fragment Size in BritishCremation Burials and its Implications for PyreTechnology and Ritual. Journal of ArchaeologicalScience 21: 339-342.
McKinley, J.I. 1994b The Anglo-Saxon Cemetery atSpong Hill, North Elmham. Part VIII: TheCremations. East Anglian Archaeology Report No.69: GB.
McKinley, J.I. 1998 Archaeological Manifestations ofCremation. The Archaeologist 33: 18-20.
McKinley, J.I. 2000 Phoenix Rising: Aspects ofCremation in Roman Britain. In: Pearce, J., Millett,M. and Struck, M. (eds.) Burial, Society and Contextin the Roman World. Oxbow Books: GB. Pp38-44.
McKinley, J.I. and Bond, J.M. 2001 Cremated Bone.In: Brothwell, D.R. and Pollard, A.M. (eds.)Handbook of Archaeological Sciences. John Wileyand Sons, Ltd.: GB.
Mayne Correia, P.M. 1997 Fire Modification ofBone: A Review of the Literature. In: Haglund, W.D.and Sorg, M.H. (eds.) Forensic Taphonomy: ThePost-mortem Fate of Human Remains. CRC Press,Inc.: USA. Pp275-293.
Mayne Correia, P. and Beattie, O. 2002 A CriticalLook at Methods for Recovering, Evaluating, andInterpreting Cremated Human Remains. In:Haglund, W.D. and Sorg, M.H. (eds.) Advances inForensic Taphonomy: Method, Theory, andArchaeological Perspectives. CRC Press, Inc.: USA.Pp435-450.
Kennedy, K.A.R. 1996 The Wrong Urn:Commingling of Cremains in Mortuary Practices.Journal of Forensic Sciences 41(4): 689-692.
De Gruchy, S. and Rogers, T.L. 2002 IdentifyingChop Marks on Cremated Bone: A PreliminaryStudy. Journal of Forensic Sciences 47(5): 933-943.
Tomita, M., Ijiri, I., Shimosato, K. and Mikami, Y.1984 The Effect of Heating on Y-chromosomeDetection. Forensic Science International 24: 43-49.
Heat & the Integumentary System
First layer of contact with the source of the heat
SkinErythema and blistersHeat contractureAM vs PM damage
Keratinous TissueHair and nails‘Clubbing’
Spontaneous Human Combustion
Explaining the urban legend…
Heat & the Internal Organs
The Muscles‘Pugilistic attitude’
The Respiratory TractInhalation of hot gases
The Internal OrgansVisceraBrain
Surviving these injuries
Damage to the soft tissues inevitably affects positive identification
Heat & the Blood
The constituents of blood are severely affected by heating and fires
Heat-induced changes to the bloodRed blood cell breakdownHeat haematomaAM vs PM damage
Toxins in the bloodCarbon Monoxide (CO)CyanideOther toxins
4 Stages of Heat-induced Degradation
As described by Mayne Correia (1997) and revised by Thompson (1999)
Stage Description Approximate TemperatureRange (°°°°C)
Dehydration Removal of Water 100-600
Decomposition Removal of OrganicComponents 500-600
Inversion Removal of Carbonates 700-1100Fusion Melting of Crystals 1000+
Secondary Heat-induced Change
Examples of secondary heat-induced change
0
20
40
60
80
100
120
Pre-
burn
ing
500o
C 1
5min
s 5m
ins
500o
C 1
5min
s 15
min
s
5 00o
C 1
5min
s 25
min
s
5 00o
C 4
5min
s 5m
ins
500o
C 4
5min
s 15
min
s
5 00o
C 4
5min
s 25
min
s
7 00o
C 1
5min
s 5m
ins
7 00o
C 1
5min
s 15
min
s
7 00o
C 1
5min
s 25
min
s
7 00o
C 4
5min
s 5m
ins
7 00o
C 4
5min
s 15
min
s
7 00o
C 4
5min
s 25
min
s
9 00o
C 1
5min
s 5m
ins
9 00o
C 1
5min
s 15
min
s
900o
C 1
5min
s 25
min
s
9 00o
C 4
5min
s 5m
ins
900o
C 4
5min
s 15
min
s
9 00o
C 4
5min
s 25
min
s
Burning Conditions
Num
ber o
f Mea
sure
men
ts R
ecor
ded
4 Stages of Heat-induced Transformation
Redesigning Mayne Correia (1997) and Thompson (1999)
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
Dehydration
Decomposition
Inversion
Fusion
Temperature (°°°°C)
The intricate inter-relationship between the heat-induced changes
1200
1100
1000
900
800
700
600
500
400
300
200
1000
Temperature (°°°°C)
Dimensional Change
Porosity Change
Recrystallisation
Changes in Strength
Fracture Formation
Weight Loss
Colour Change
Modeling Heat-induced Change
Heat-induced Dimensional Change
Here we see both the presence of H-i expansion and shrinkage
Dimension 500oC15mins
500oC45mins
700oC15mins
700oC45mins
900oC15mins
900oC45mins
5 Minutes 1.94 1.2 1.64 2.44 5.52 5.3515 Minutes 1.96 1.39 1.81 2.92 5.56 5.57D125 Minutes 1.96 1.5 1.95 3.34 5.69 5.765 Minutes 0.9 0.88 4.25 19.33 7.29 14.45
15 Minutes 0.86 1.47 4.86 5.58 8.03 15.16D225 Minutes 0.87 1.83 5.23 6.24 9.1 15.715 Minutes 0.79 -4.53 -1.72 3.07 6.52 36.18
15 Minutes 10.13 -3.84 -1.1 4.4 7.4 37.06D325 Minutes 0.84 -3.19 -0.37 5.22 8.73 37.685 Minutes -1.59 1.15 14.09 5.24 19.15 14.62
15 Minutes -1.59 1.15 14.6 6.88 20.54 16.2D425 Minutes -1.46 2.06 15.68 8.67 21.55 16.475 Minutes 2.67 3.04 7.02 6.02 10.62 4.96
15 Minutes 2.7 3.61 7.57 6.88 11.59 10.39D525 Minutes 2.73 4.14 8.29 7.26 13.58 10.795 Minutes 0.93 6.57 3.88 4.1 5.67 -3.92
15 Minutes 1.06 7.35 5.1 5.06 6.77 -2.71D625 Minutes 1.06 8.04 5.82 5.85 7.94 -1.935 Minutes 2.34 10.15 11.64 7.32 15.26 -2.04
15 Minutes 2.4 11.16 12.45 8.53 16.64 -0.6D725 Minutes 2.4 13.04 13.59 9.57 21.12 0.155 Minutes 3.28 0.47 5.51 7.42 9 24.57
15 Minutes 3.35 1.28 6.25 8.32 10.04 25.4D825 Minutes 6.13 1.82 6.77 9.1 10.43 26.235 Minutes 6.83 -0.12 0.85 7.81 15.86 12.32
15 Minutes 6.94 0.98 1.97 9.12 17.99 13.66D925 Minutes 6.97 1.86 6.24 9.66 19.35 14.85 Minutes 5.79 -0.07 7.27 4.62 9.43 11.98
15 Minutes 5.84 0.83 8.02 5.74 10.63 13.17D1025 Minutes 5.77 1.72 9.52 6.47 11.66 13.765 Minutes 7.65 -0.45 5.24 5.92 11.81 18.18
15 Minutes 7.65 0.64 6.5 6.38 13.68 19.17D1125 Minutes 7.75 1.68 7.61 7.7 16.5 20.66
Influences on H-i Transformations in BonePrincipal Component
1 2 3 4 5Temperature 0.392 0.565 0.669 0.233 0.161
Duration -0.506 0.332 -0.099 -0.196 0.765% Weight loss -0.832 0.190 0.438 0.280 0.033
Number ofMeasurements -0.138 -0.890 -0.209 -0.357 -0.132
Crystal Size 0.257 0.517 0.533 0.210 0.582Skeletal Density 0.020 0.091 -0.940 0.300 -0.133
Bulk Density 0.676 -0.071 0.371 0.642 -0.158Microporosity 0.103 -0.223 -0.921 -0.269 -0.136Mesoporosity 0.096 0.934 -0.145 0.240 0.202Macroporosity -0.952 -0.116 -0.104 -0.241 -0.105D1 % Change -0.321 0.686 0.178 0.018 0.628D2 % Change 0.448 0.342 0.689 -0.015 0.455D3 % Change 0.766 0.182 0.248 0.153 0.544D4 % Change 0.985 0.094 0.123 0.068 -0.032D5 % Change -0.304 0.849 0.346 -0.259 0.023D6 % Change -.0941 -0.113 0.173 -0.193 0.188D7 % Change -0.876 0.297 -0.132 -0.356 0.036D8 % Change 0.148 0.091 0.355 0.194 0.898D9 % Change 0.351 0.075 0.199 0.911 0.034D10 % Change 0.680 -0.230 0.381 -0.427 0.397D11 % Change 0.025 0.376 -0.267 0.865 0.196
Major PCA associations (>0.550, <-0.550) are highlighted
A Unified System
Countering the false dichotomy between soft and hard tissues
Forensic vs Medicine vs ArchaeologyExperimentsPublicationsCollaborations
Body TissuesInfluence of soft on hard tissuesInfluence of hard on soft tissues
H-i Influences on Anthropological Methods
Heat-induced Change Technique Affected Cause of Effect
Colour Change MetricIndirectly: Colour changeimplies loss of organicswhich causes shrinkage
Weight Loss MetricIndirectly: Weight loss
implies loss of organicswhich causes shrinkage
Fracture Formation Morphological and Metric
Directly: Increasedfragmentation reduceslikelihood of technique
application
Changes in Strength Morphological and Metric
Indirectly: Weaker boneincreases fragmentation
which reduces likelihood oftechnique application
Recrystallisation Morphological and Metric
Directly: Changes inmicrostructure may affect
shape and will affectdimensions.
Porosity Change MetricIndirectly: Implies loss of
organics and reorganisationof microstructure.
Dimensional Change Morphological and MetricDirectly: Differential size
changes may affect shapeand will affect dimensions.
There is no way to avoid H-i changes when analysing burned bone
Predicting the Influence of Heating
DependentVariable Equation (using most appropriate variables) R2 Value
D1 % Change -D2 % Change -15.564 + 1.5 (Crystal Size) 0.848D3 % Change 25.726 - 468.258 (Macroporosity) 0.757D4 % Change 25.208 Š 311.342 (Macroporosity) 0.950D5 % Change -D6 % Change -1.750 + 242.815 (Macroporosity) 0.842D7 % Change 6.948 + 184.843 (Macroporosity) 0.751D8 % Change -10.615 + 1.426 (Crystal Size) 0.837D9 % Change -34.544 + 27.957 (Bulk Density) 0.737D10 % Change -D11 % Change -Temperature 207.015 + 31.850 (Crystal Size) 0.704
Duration -D1 % Change -1.023 + 0.131 (Duration) 0.789D1 % Change -6.273 + 0.131 (Duration) + 0.0075 (Temperature) 0.928
D1 % Change5.606 + 0.138 (Duration) Š 0.0607 (Number of
Measurements) Š 1.092 (Skeletal Density) + 0.01354 (%Weight Loss)
1.000
Linear regression equations [Note: dash indicates an equation could not be created]
Comparison of Prediction Equations
DependentVariable Prediction Equation R2 Value
D1 % Change Shipman et al (1984)0.302X3 + 0.0000826x2 + 0.0000000704x Š 0.688 0.775
D1 % Change This Research-1.023 + 0.131 (Duration) 0.789
D1 % Change This Research-6.273 + 0.131 (Duration) + 0.0075 (Temperature) 0.928
Additional variables improves description of sample
H-i Influences on Other ID Methods
Identification Technique Influenced by BurningHuman Bone Burning affects histology
Facial Reconstruction Facial bones shrink, distort and fractureDNA Destroyed Š but SNP and may survive in
micronichesOdontology Teeth suffer dimensional changes, fracture and
explodeFinger Prints Destruction of distal body parts
Ear Print Ears burned away
The potential of the British Association for Human Identification [www.bahid.org]
Conclusions
• Need to change attitudes in forensic anthropology andpathology with regard to the unification of the two tissuesystems and the identification information that can beextracted
• Need more basic data on the fundamental primary-levelheat-induced changes in bone
• Need a more coherent approach to all fire-orientedidentification research
• Refine and modify anthropological techniques of humanidentification
Relevant References
McKinley, J.I. 2000 The Analysis of Cremated Bone. In: Cox, M. and Mays, S. (eds.)Human Osteology: In Archaeology and Forensic Science. Greenwich Medical MediaLtd: GB. Pp403-421.
Mayne Correia, P.M. 1997 Fire Modification of Bone: A Review of the Literature. In:Haglund, W.D. and Sorg, M.H. (eds.) Forensic Taphonomy: The Post-mortem Fate ofHuman Remains. CRC Press, Inc.: USA. Pp275-293.
Thompson, T.J.U. in press Heat-induced Dimensional Changes in Bone and their Consequences for ForensicAnthropology. Journal of Forensic Sciences.
Thompson, T.J.U. 2004 Recent Advances in the Study of Burned Bone and their Implications for Forensic Anthropology.Forensic Science International 146S: S203–S205.
Hiller, J., Thompson, T.J.U., Evison, M.P., Chamberlain, A.T. and Wess, T.J. 2003 Bone Mineral Change DuringExperimental Heating: An X-ray Scattering Investigation. Biomaterials 24(28): 5091-5097.
Thompson, T.J.U. 2002 The Assessment of Sex in Cremated Individuals: Some Cautionary Notes. Canadian Society ofForensic Science Journal 35(2): 49-56.
Thompson, T.J.U. 2003 An Experimental Study of the Effects of Heating and Burning on the Hard Tissues of the HumanBody and the Implications for Anthropology and Forensic Science. Unpublished PhD Thesis, University of Sheffield.
Acknowledgements
This research formed the bulk of a doctoral project undertaken in the Departments ofForensic Pathology and Archaeology, University of Sheffield, UK. The practical aspectof this research could not have been achieved without the help, advice and time of thefollowing people: my supervisors Dr Martin Evison (Forensic Pathology) and Dr AndrewChamberlain (Archaeology); Erika Petersen (Archaeology, University of Sheffield) andRichard Stacey (Chemical and Process Engineering, University of Sheffield) providedaccess to the muffle furnaces; Ian Newsome (Forensic Pathology, University ofSheffield) the department’s digital photography equipment; David Jarvis (ForensicPathology, University of Sheffield) assisted with the radiography and John Proctor(Biomedical Sciences, University of Sheffield) likewise the electron microscopy; Dr ColinSmith (Palaeobiology, Museo Nacional de Ciencias Naturales, Madrid), Miranda Jansand Dr Matthew Collins (Biology and Archaeology, University of York) made availableand conducted the ground-breaking use of porosimetry and Dr Jen Hiller and Prof TimWess (Biological Sciences, University of Cardiff) the same with WAXS and SAXS.Current imaging work is being conducted with Dr Sandy Chudek. Thanks to Dr BeckyGowland (St John’s College, University of Cambridge) who gave advice and commentson the draft versions of this paper as well as throughout the research.
Thanks also to the International Association of Arson Investigators for allowing me theprivilege of presenting this research here.
Contact Details
Dr Tim Thompson
Unit of Anatomy & Forensic AnthropologySchool of Life Sciences
University of DundeeDow Street, Dundee, DD1 5EH, Scotland
T: +44 (0) 1382 344220E: [email protected]