Interview with Forensic Archaeologist & Researcher Amy Rattenbury

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What is your current job role and what does this involve?

By training I’m a Forensic Archaeologist but currently work as a lecturer at Wrexham Glyndwr University teaching on the BSc (Hons) in Forensic Science. My day to day job is teaching student groups across all three years of the programme in a range of subjects such as Crime Scene Investigation, Anatomy & Pathology and the Forensic Investigation of Mass Fatalities. As well as delivering the theory I set up a lot of the practical work that the students do such as fingerprinting workshops, organ dissections and simulated crime scenes that we mock up in our Crime Scene House. I also supervise a number of student research projects mainly in the area of Taphonomy which we conduct on our ‘Body Farm’

What initially attracted you to this field of work?

I had always been interested in science and particularly forensic science and initially took a degree in Forensic Biology at Staffordshire. I always imagined that I would go on to work in a laboratory or doing fingerprint comparisons until I took a module in ‘Identification of Human Remains’. This really sparked my interest in human osteology and made me pursue a MSc in Forensic Archaeology and Crime Scene Investigation at Bradford University where I found my very niche area in search and recovery of human remains. I started teaching anatomy alongside completing my MSc and found a real love for being in the classroom. It gives me an ideal role in being able to share what I’ve learnt so far whilst still being able to pursue my own research and industry related work. Looking back now I can’t imagine not being a teacher. There’s something about introducing students to concepts they had never considered before that really exciting. And sometimes they come back to you later on in their academic careers and actually end up teaching you something; that’s a really rewarding feeling.

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Can you tell us about the research you are currently involved in at Wrexham Glyndwr University?

We are really lucky here at Glyndwr to have Wales’ first and only Taphonomic Research Facility which is licensed by DEFRA. This ‘Body Farm’ allows us to conduct a number of research projects looking at decomposition which could necessarily be hosted by other universities without a dedicated, rural area in which to conduct their research. This coupled with a high calibre research lab in our Chemistry Department has really allowed both myself and students to expand research ideas. Current student projects which are out on the body farm include:

  • The effect of clandestine burial decomposition on soil chemistry and vegetation
  • How tattoo identification is effect by post mortem changes
  • A comparison of decomposition rates in fresh and stagnant water

I am also hoping to set up my own research once the temperature improves slightly and this will be looking at how oxygen deprivation (i.e. vacuum packing) affects taphonomic changes. This is a research project based on a pilot study I supervised, conducted last year by Shareei Singer at the University Centre Southend, and we hope to expand this further by looking at more samples, over a longer time frame whilst also improving the analysis methods used.

What are some of the biggest challenges in your field of work?

Teaching is a challenging role in the first place, but even more so at University level where there is an increased need to challenge students academically, and this can be particularly difficult field to get in to early in a professional career. I’m only 25 so it’s been very much a case of putting myself out there for any and every opportunity to prove myself and gain any experience I can. You really have to show not just your ability as an academic but also a drive and passion for the subject and the students. It is a highly competitive area, not only in terms of securing jobs in the first place, but then going on to conduct and publish research whilst still maintaining high quality, engaging session, for students every week. For me in particular, I find the sheer volume of books and journals I have to read, to ensure that my delivery keeps up with the speed that the area is progressing, a little daunting. But when it’s a subject that I’m passionate about, and books I would likely read anyway, it does make it easier!

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Aside from research, are you often involved in police casework or consultancy work, and what does this typically involve?

I’m not currently involved in any active police work but I did only move up to North Wales around 6 months ago. It is something that I am very keen to start and hope to build up connections in the area to so this. I do some other consultancy work in different areas of forensic search. I work quite closely with UK-K9 who are a search dog training team. They specialise in training dogs to search for a variety of forensic evidence including human remains, explosives and drugs. We are currently working to improve the use of the human remains detection dogs on water and particularly in salt water setting such as costal searches. They are also involved in a lot of cold case reviews and large scale searches which I can offer an archaeological perspective on. I have also recently taken up a consultancy position with Kenyon International Emergency Services who deal with crisis incidents world-wide. I am currently awaiting deployment but once I am called in the role could be anything from collecting evidence at aeroplane crash sites to helping with disaster victim identification during natural disaster.

Do you have any words of advice for students wishing to pursue a career in your field of work?

For students wanting to go in to the forensic science generally just make sure you have it clear in your head before you start that it isn’t going to be how you see things portrayed in the media, I wouldn’t want you to be disappointed or put off once you start the course. I would say trying to get any sort of work experience is going to be crucial. Experience is essential nowadays but still almost impossible to get in crime related areas so think outside of the box a little bit. There are lots of labs you could do placements in that, although aren’t forensic can help you to learn and demonstrate key skills. I worked in a drinking water testing lab and in a haematology lab for a little while, both of which helped learn more about preventing cross contamination. But there are lots of other areas you can volunteer in such as becoming a PCSO, the Appropriate Adult services or any other charity that deals with victims of crime or offenders.

For students wanting to become educators I would say persevere. Remember what made you so passionate about that subject in the first place and share this with you students. It’s amazing how much more progress you make once you’ve learnt to foster this positive learning and collaborative environment. The planning and the marking will get easier, I promise!

 

Follow Amy on Twitter at @amy_rattenbury

Forensics at Glyndŵr can be followed on Twitter or Facebook.

Interview with Postgraduate Researcher Winsome Lee

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What is the focus of your research at the University of Leicester?

My research focus, namely for my dissertation is a comparative study of the forensic science progression in Hong Kong over a 40 years time frame. Hong Kong is where I have been brought up, and forensic science in the city is always covered with the mysterious veil. In 1965, we had our first forensic case. Till today, more than 40 years have passed by, it will be essential to evaluate how much we had progress.

Other than the dissertation research, since my focus is on forensic anthropology and forensic archaeology, I am also doing different excavation field schools, projects,  and osteology related research with other institutions.

Why is this research important to the field of forensic science and what do you hope to achieve by carrying out this research?

Technology and forensic techniques develop in a pace that we would never catch up with. However, due to constraints, not much comparative studies have been done, as an evaluation of the progress and development of the field, on the one hand. Sadly, funding is usually not entirely willing to sponsor studies of this sort, as they are hoping for new discovery most of the time, which likely lead to over generalization of ideas. Given the fact that forensics subjects heavily to experiences and contexts. Therefore, comparative study of forensic science is something that the profession needs yet tends to be overseen usually. On the other hand, a historical comparative study like the captioned one above, shows the same model over different time frames. It allows us to see the approach or policy from a macro level, namely environmental and political factors. In hope of this research, the government and the law enforcement will make improvements of their policies and models in order to facilitate the growth and application of forensic science in Hong Kong.

What does life as a postgraduate researcher entail?

Grad school life, as we all know, is tough. It is the kind of life that you have a full plate and always do not know where to start with. A lot of time management is involved, especially when I am also working alongside the study. People say you can use the senior year of undergraduate as a postgraduate tryout, I find this mostly correct! Also, other than studying, you are constantly looking for research and publication opportunities. Every time, when we are struggling, my pals and I keep asking ourselves, “why would we do this to ourselves.” But the sense of achievement is never better when you have accomplished something and survived a semester after another.

What are your plans for after you have completed your research?

After completing the existing project in the University of Leicester, I would be looking for PhD opportunities in either bioarchaeology, or biological anthropology.

Also, I have several real life forensic projects with police and other authorities ongoing and lined up. I am all excited and looking forward to all these amazing opportunities ahead!

Do you have any advice for students hoping to pursue a position in forensic research?

Keep your mind open!

First of all, forensic science itself is a relatively broad profession. Some of my friends switched from one discipline to another after trying out things, from forensic anthropology to law, from forensic pathology to forensic photography. You never know until you have tried. So first thing will be, to grasp as many opportunities as you can, then decide.

Once you made your choice, you also have to remember that forensic scientist is a relatively narrow yet competitive profession. What I mean is that, there is only certain demand in the authorities or law enforcement for forensic experts. If no one retires, you probably will not get a job. So it is always beneficial to have a broader, or second profession focus besides forensics.

Also, it is also very important to know that not every forensic scientist is good with doing research. Some are good with applying what we have learned, rather than doing research and making new discoveries. Be open minded, and do not get frustrated! Keep in mind that, either way we are making remarkable contribution.

Follow Winsome’s blog “Traces in Bones” here.

Interview with Biological & Forensic Anthropologist Dr Geraldine Fahy

Geraldine Fahy

What is your current job role and what does this involve?

I am a lecturer in Biological/Forensic Anthropology in the Skeletal Biology Research Centre, University of Kent. During term-time I teach all aspects of Human Evolution from early fossil hominins, hunter-gatherer societies, to methodologies used to reconstruct the last common ancestor (LCA). I also convene a forensic anthropology module where I teach forensic taphonomy, excavation and recovery, disaster victim identification and biometric identification. We are in the process of developing our MSc Forensic Osteology and Field Recovery Methods which will run from Sept. 2017 which is very exciting!

What initially attracted you to this field of work?

I wanted to become a forensic anthropologist from the first time I read Kathy Reich’s debut novel, Deja Dead. Of course, fiction is fiction however by the time I started researching the topic and where I could study forensics, I loved the topic for itself, for the science and so continued. I have turned more towards analytical chemistry techniques and human evolution in recent years; however, my interest in forensics continues, and my education and employment background remains relevant, as most forensic science disciplines, including forensic anthropology, have solid foundations in science, with the ‘forensic’ aspect being related to chain-of-custody maintenance and courtroom presentation.

Can you tell us about the research you are currently involved in at the University of Kent?

I conduct research into dietary ecology and subsistence patterns of past populations using stable isotope analysis. I have previously conducted such research on a population of wild Western chimpanzees, as correlates for the LCA; however, my current research focuses on medieval dietary reconstruction from East and West Europe. I am also currently involved in a project looking at the effects of bone turnover rates on stable isotope values and am currently investigating potential stable isotope methodologies that may have future use in forensic identification.

Has your work led you to be involved in any legal investigations? If so, what did this involve?

I worked as a forensic anthropology intern at the Netherlands Forensic Institute where I looked at decomposition of muscle tissue following submersion in water for my MSc thesis. Following this I worked as a forensic anthropology intern for the UN Mission in Kosovo in 2007 where I assisted in the identification and repatriation of victims of the Yugoslavian conflict. Subsequently I worked as an Associate Forensic Expert for the UN International Independent Investigation Commission in Lebanon which involved evidence collection and cataloging in the investigation of the assassination of former Lebanese Prime Minister Rafik Hariri and others.

Do you have any words of advice for students wishing to pursue a career in forensic anthropology?

Do your research but don’t be disheartened if you end up doing a different degree initially; as long as it’s not totally removed (e.g. doing a business degree when you then want to work in science) it is possible to get where you want to go without a straight path. I would advise doing as many unpaid internships as possible, this is where you gain valuable experience and make contacts for the future. Importantly realise that what you want can change as the years go by and this is fine….you may start out wanting to work constantly in the field, but then realise this is not viable for you and end up in a lab or a classroom, just go with whatever feels right for you.

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Interview with Forensic Anthropologist Dr Anna Williams

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What is your current job role and what does this involve?

I am Principal Enterprise Fellow (equivalent to Reader or Associate Professor) in Forensic Anthropology at the University of Huddersfield. My time is divided between teaching undergraduate and postgraduate students, supervising MSc and PhD students, and doing research and forensic casework. I teach on the BSc/MSci Forensic and Analytical Sciences, and the MSc in Forensic Anthropology and the MSc in Risk, Disaster and Environmental Management. Part of my role is also to engage with the public and communicate our research to lay people, including school children, interested adults and other scientists. I regularly present at academic conferences, local interest groups, Science Festivals and public events. This year, I am presenting at the Royal Society Summer Science Exhibition. I have also been featured in several TV science documentaries, and regularly consult for TV shows like Bones, Rosewood and Silent Witness. I also write a blog about my adventures in forensic anthropology.

What initially attracted you to this field of work?

I did a mixture of sciences and humanities at A Level and could never decide which I liked best, so I chose Archaeology and Anthropology as my first degree. There, I was fascinated by what you could tell about individuals by their skeletal remains, for example about hominid evolution. Then I discovered the burgeoning science of Forensic Anthropology, on a short course at Bradford University, and that was it, I was hooked! I love how you can glean all sorts of information from the smallest pieces of evidence. I have always loved logic problems, and forensic anthropology offers the most exciting puzzles. The fact that it is often confronting, challenging and disturbing, and could help to bring criminals to justice, just serves to add to its appeal for me.

Can you tell us about the research you are currently involved in at the University of Huddersfield?

I specialise in decomposition and taphonomy (the study of how bodies decay in different environments). To do this, I use an outdoor decomposition laboratory. I lead a research group currently doing research into the gases given off by decomposing cadavers (we use pigs that have died of natural causes), and comparing that to the efficiency of police dogs that are specially trained to find dead bodies. We’re also looking at how skin colour changes in surface or water environments, and trying to find ways to improve our estimation of post-mortem interval and post-mortem submersion interval. Other research is focussed on the taphonomic changes that occur to bone and teeth in hot, arid environments. I am also running a citizen science project in order to improve age estimation of unknown individuals from dental eruption. There is a webpage and online questionnaire for anyone who would like to help us build a large, modern set of tooth eruption data to see if dental eruption ages are changing.

Aside from research, are you often involved in police casework, and what does this typically involve?

Sometimes I am asked by the police to attend crime scenes or mortuaries to undertake forensic examination of decomposed or skeletonised remains. They can be either the victims of crime, or the remains of people who have gone missing. I will determine whether they are human or animal, and if they are human, I will estimate the age at death, sex, stature and ancestry of the individual(s), and try to say something about their lifestyle, disease, injury and how they died. I work in conjunction with forensic archaeologists and odontologists, as well as pathologists, to reach an identification. I also do consultancy for forensic science providers and, on occasion, a mass disaster company that helps to ‘clean up’ after disaster and repatriate the victims. I am involved in disaster victim identification and the Emergency Operations Centre.

The existence of so-called ‘body farms’ has sparked great interest in the media. Are there plans to establish such a facility in the UK? What are the primary challenges associated with this?

I believe that Human Taphonomy Facilities, or ‘Body Farms’ as they have become colloquially known, are vital for the advancement of forensic science. We owe all that we know already about human decomposition to the Forensic Anthropology Center at the University of Tennessee, and there is so much more to learn. We need to know how human conditions like diabetes, cancer, smoking and drug use affect our decomposition, which is something we cannot learn from experimenting with dead pigs. Unfortunately, a lot of the data generated by the ‘Body Farms’ in the USA and Australia are not directly relevant to forensic cases in the UK or Europe, because of the different climate, insects and scavengers. The UK is falling behind the USA and Australia by not having one of these outdoor laboratories where vital decomposition research can be done on donated cadavers. There was an attempt to establish a Body Farm in the UK in 2011, but this failed for a variety of financial and political reasons. I think the main obstacles to getting one set up in the UK are lack of funding, public awareness and rivalry between academic institutions. I hope that, in the near future, we will be able to create a facility where researchers, academics and practitioners will be able to work together to improve methods of search and recovery, post-mortem interval estimation and identification of human remains.

Do you have any words of advice for students wishing to pursue a career in forensic anthropology?

Forensic anthropology is a very competitive field, and there aren’t many jobs out there, so you need to be dedicated and determined. It can also be hard work and distressing, so decide carefully whether you want to pursue a career in it. The best way to make yourself stand out from the crowd of other applicants to jobs is to have experience, so try to get as much hands-on experience as you can. This doesn’t have to be forensic (although, of course, that would be preferable), but can be in archaeological units or museums or hospitals (or even zoos), somewhere where you can deal with human (or animal) bodies.

Images from Research

These pictures show the progression of decomposition in a small (10kg) pig. The first picture shows the pig in the fresh stage, when post-mortem interval was less than 24 hours. The second picture shows the pig in the active decay stage, 25 days later. The brown froth is decomposition fluid that has been agitated by the movement of maggots. The body was bloated with decomposition gases, but has now collapsed, and the intestines are escaping. The skin has desiccated, but the hair is still intact. The skin has darkened and become leathery in texture. The bones are becoming detached from the body.

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Surface pig 1, day 0

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Surface pig 1, day 25

 

Website: www.forensicanna.com

Twitter: @Bonegella

Also, you can follow #scentofdeath and #teamtaphonomy

Scientist Special: William R. Maples

“That’s how I feel about the skeletons in my laboratory. These have tales to tell us, even though they are dead. It is up to me, the forensic anthropologist, to catch their mute cries and whispers, and to interpret them for the living, as long as I am able”. – William R. Maples in Dead Men Do Tell Tales.

William R. Maples (Source: http://anthro.ufl.edu)

William R. Maples (Source: http://anthro.ufl.edu)

As an internationally-renowned forensic anthropologist, William R. Maples travelled the world to offer his expertise to over a thousand cases, fighting to not only identify skeletal remains but also uncover how they died.

Born on 7th August 1937 in Dallas, Texas, Maples developed an early fascination with anthropology and death investigation, allegedly when a deputy sheriff showed him autopsy photos of the infamous duo Bonnie and Clyde. After receiving his Master’s Degree in 1962, he spent a short time working in Kenya studying primates, later being awarded his PhD in anthropology from the University of Texas in 1967. He began his career with a number of teaching positions at Western Michigan University and the University of Florida at Gainesville, later taking on the role of Curator of Physical Anthropology at the Florida State Museum. He was President of the American Board of Forensic Anthropology and a fellow of the American Academy of Forensic Sciences.

During the 1970’s, Maples began offering his expertise to legal death investigations, aiding in the identification of victims and conclusion of cause of death, working with a number of police departments. This further extended to working alongside the U.S Army’s Central Identification Laboratory in Hawaii, examining the remains of military personnel.

Throughout his career he applied his expertise and guidance to hundreds of cases, some of which involved particularly high profile investigations. Perhaps his most famous case is that of the investigation of the Romanov family. The Romanovs were members of a Russian royal family with Nicholas II as Tsar. However in 1918 he was forced to give up his throne and he and his family were arrested and brutally executed by the Bolsheviks, a group of Russian communists who would soon become the dominant political power in Russia. In the early 1990s the bodies of the Romanov family were recovered from a mass grave, with William Maples leading a team of forensic experts in the investigation. They ultimately concluded that the remains were in fact those of the members of the Romanov family, with DNA testing confirming this.

In 1991 Maples was also part of the team examining the remains of former President Zachary Taylor, rumoured to have been murdered by arsenic poisoning. A former humanities professor at the University of Florida, Clara Rising, called for further tests to be carried out, convincing Maples to lend a hand and examine the remains. His investigation aimed to put these claims to rest and ultimately concluded that the cause of death had been gastroenteritis.

In 1994, Maples was part of the team that laid to rest a vicious murder case from the 1960s. In 1963, civil rights leader Medgar Evers was assassinated as he returned home one day. When taken to hospital, he was at first refused entry because of his race, and later died, bitterly just hours after President John F. Kennedy delivered a speech in support of civil rights. White supremacist and member of the Ku Klux Klan Byron De La Beckwith was arrested under suspicion of his murder, but managed to escape justice. But 30 years later when the case was re-opened, William Maples helped exhume the remains of Evers for an autopsy, eventually leading to the long overdue conviction of Beckwith.

This scrapes the surface of Maples’ involvement in death investigations, which extends to the examination of the remains of Joseph Merrick (the ‘Elephant Man’), the investigation of the 1996 ValuJet 592 disaster, and the study of the remains of victims of the Gainesville student murders.

In 1995 he was diagnosed with brain cancer and, although continuing to work for two more years despite this, passed away on 27th February 1997 at the age of 59 years.

You can read William Maple’s book, Dead Men Do Tell Tales: The Strange and Fascinating Cases of a Forensic Anthropologist, to gain a further insight into his life and career.

References

Herszenhorn, D. M. 1997. William. R. Maples, 59, Dies; Anthropologist of Big Crimes. [online] Available: http://www.nytimes.com/1997/03/01/us/william-r-maples-59-dies-anthropologist-of-big-crimes.html

Maples Center for Forensic Medicine. W. R. Maples. [online] Available: http://maples-center.ufl.edu/organizations/people/william-r-maples

Maples, W. R. Browning, M. 2010. Dead Men Do Tell Tales: The Strange and Fascinating Cases of a Forensic Anthropologist. California: Doubleday.

Williams, R. C. 2015. The Forensic Historian: Using Science to Reexamine the Past. Abingdon: Routledge.

From Mummies to Grave Wax – The Preservation of Human Cadavers

From Mummies to Grave Wax – The Preservation of Human Cadavers

Warning: Graphic images included.

When we envisage the decomposition of a corpse, the images that probably come to mind are of a rapidly-decayed, foul-smelling body quickly turning to sludge and bones. But there are actually other pathways a body can take following death, some of which can be of great importance in a forensic investigation. I’m namely talking about mummification and adipocere.

Mummification

Thanks to the Ancient Egyptians, we all know about mummification, a particular process of body preservation. When these guys mummified their dead, this routine typically involved the removal of the internal organs, most notably the brain, which was pulled out through the nostrils. Finally, the body would be wrapped in linens and salt and left to dry. The end result would be a remarkably well-preserved body displaying features that would have usually been lost to decomposition.

Aside from this especially famous post-mortem ritual, there are actually a number of ways by which a body can become mummified. For instance, more modern intentional mummification would utilise chemicals to preserve the body. But how can mummification occur naturally, and what are the implications of this in a forensic investigation?

The natural preservation of a cadaver is highly dependent on the surrounding environment, with only very specific conditions causing the body to mummify. A range of factors can play a part in this phenomenon, including temperature, humidity and the action of bacteria and other microorganisms.

In hot, dry climates moisture can evaporate from the skin at such an accelerated rate that the process of mummification can occur. As the skin is rapidly dehydrated, it often takes on a dark and leathery appearance. The internal organs may be preserved to an extent, though will typically undergo some level of decomposition so are at least likely to be smaller in size. Hot, dry climates can also hinder bacterial growth, limiting the bacterial decay and further preserving the body. Hot, sandy deserts are perhaps amongst the first scenarios that come to mind when considering mummification, but mummified remains have also be discovered in attics, basements, and even within the walls of buildings.

Conversely, especially cold and dry environments can also bring about mummification. The cold temperatures can significantly slow microorganism activity, once again reducing the rate of decomposition and aiding in preservation. A famous example of this is the natural mummy Otzi the Ice Man, believed to have died thousands of years ago but preserved through mummification induced by extremely cold temperatures.

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Mummifying conditions are not limited to temperature-based factors. Environments of extreme salinity (salt content) can preserve cadavers. The majority of bacteria cannot survive in highly salty conditions, thus severely reducing microbial action on the body. Furthermore salt itself acts as a desiccant on the soft tissue, dehydrating the body and drawing out water much as high temperatures would. An example of this type of mummification was experienced in Iran, where a number of mummies were found in the Chehrabad salt mines.

Mummified remains have also been found in bogs or marshland, in which the excess water, organic material and anaerobic (oxygen-free) environment prevents a great deal of bacterial action, thus preserving the body. This is something of a contrast to the typical hot, arid conditions mostly associated with mummified remains, but bogs with particularly acidic water, low temperatures and a lack of oxygen can essentially pickle a body. Thousands of these “bog bodies” have been recovered over the years, perhaps the most famous being the Lindow Man, determined to be the victim of a prehistoric ritual killing.

The conditions described may not necessarily induce mummification throughout the entire cadaver, but in some cases may cause localised mummification, if only particular areas of the body are exposed to these conditions. Mummification most often occurs in the face, scalp, chest and back, but typically begins in the extremities such as the fingers and toes.

Adipocere

Another phenomenon that can assist in preservation of a cadaver is the formation of adipocere. Known as “grave wax”, this is a soapy, white or grey wax composed primarily of saturated fatty acids such as palmitic and stearic acid formed through the hydrolysis and hydrogentation of body fats (Forbes et al, 2005). Numerous theories have been put forward to suggest how adipocere forms, namely the saponification, hydrogenation and fat migration theories.

A cadaver presenting adipocere. Credit: Kumar et al, 2009

The type of environment required for adipocere formation is somewhat different from that suitable for mummification. It is often encountered in especially humid graves with little or no air access, thus oxygen-poor, such as a bog or certain bodies of water. The formation of adipocere can take weeks if not years to form depending on the climatic conditions, the rate at which it forms being further affected by the environment and circumstances surrounding the cadaver. Depending on the extent to which it forms, adipocere can produce a waxy layer across the body and act as a barrier against the usual process of decomposition, providing significant protection over time as adipocere itself is fairly resistant to decay.

So these are some of the alternative routes of decay a body can take post-mortem. But what does this mean to the forensic scientist?

In some cases, the occurrence of mummification or adipocere formation can be of assistance to a forensic investigation, as it may be possible that certain aspects of the deceased person’s appearance and even any injuries they might have acquired will be preserved. Mummified tissues can even be rehydrated to aid in visualising injuries and other distinguishing marks. Similarly, the formation of adipocere can preserve tissues and organs along with recognisable facial characteristics. This can in theory aid in identification if the victim is unknown or even determining cause of death.

Furthermore, just as the stage of decomposition of a body can roughly indicate the post-mortem interval (time since death), mummification and adipocere can provide some indication in that a certain amount of time is required for mummification to occur. Approximately 6-12 months are required for the natural mummification of an adult, with a child’s body requiring less time to become mummified (Gitto et al, 2015), though in some cases mummification has been reported in a matter of weeks or even days (Sledzik and Micozzi, 1997). Of course these time periods can vary widely depending on climatic conditions and a number of other factors, but they may provide assistance nonetheless. To an extent it may be possible to determine the rough age of the remains based on the weight of the mummified cadaver, as more recent bodies will be heavier than those which are older and have lost a greater proportion of water content.

So given the right conditions, processes such as mummification and adipocere formation can interestingly be a great aid to the forensic investigator.

References

Bereuter, M. T. L. Lorbeer, E. Reiter, C. Seidler, H. Unterdorfer, H. Post-morten alterations of human lipids – part I: evaluation of adipocere formation and mummification by desiccation. Human Mummies. 3 (1996), pp. 265-273.

Bryd, J. H. Castner, J. L. 2010. Forensic Entomology: The Utility of Arthropods in Legal Investigations. Boca Raton, Florida: CRC Press.

Forbes, S. L. Bent, B. B. Stuart, H. The effect of soil type on adipocere formation. For Sci Int. 154 (2005), pp. 35-43.

Gitto, L. Bonaccorso, L. Maiese, A. dell’Aquila, M. Arena, V. Bolino, G. A scream from the past: A multidisciplinary approach in a concealment of a corpse found mummified. Journal of Forensic and Legal Medicine. 32 (2015), pp. 53-58.

Kumar, T. S. M. et al. Early adipocere formation: A case report and review of literature. Journal of Forensic and Legal Medicine. 16 (2009), pp. 475-477.

Rich, J. Dead, D. E. Powers, R. H. 2005. Forensic Medicine of the Lower Extremity. Totowa, New Jersey: Humana Press Inc.

Geochemistry and Clandestine Graves

Geochemistry and Clandestine Graves

Perpetrators of fatal crimes will on occasion attempt to conceal their wrongdoings by burying the evidence – that is, attempting to bury human cadavers. This can be problematic during a forensic investigation for a number of reasons. Firstly, the search for a victim’s body may well be relatively blind, with investigators having little or no idea as to where a body has been buried. In some instances, a body may well be so damaged or decomposed that little recognisable human remains are present. The perpetrator may later remove the body from the burial site, perhaps fearing discovery, leaving behind no obvious trace that a body was ever buried there.

So what can investigators do to determine if an area of soil was the site of a clandestine grave (illicit burial site)? A number of methods that have been developed to tackle this question.

grave

Certain chemical compounds may be indicative of decomposing flesh. Sterols have been suggested as a potential biomarker for decomposition fluids – that is, the presence of them in soil could indicate whether or not a body has decomposed in that location, depending on the types of sterols present and in what amounts. Sterols are a class of organic compound, of which cholesterol is perhaps the most well-known sterol present in animal cells. This compound can be found in plants too, but in a significantly smaller amount, thus the unexpected presence of cholesterol in soil will typically indicate some kind of animal-related activity. Research examining the decomposition fluids in soils found sterols to be beneficial in this application (Von der Luhe et al, 2013). A number of pig carcasses were buried over a few months, with soil samples being collected from underneath the cadavers at different time points after burial. Cholesterol and coprostanol were detected in the soil, and it is these substances that were of particular interest to the researchers. Coprostanol is formed via hydrogenation of cholesterol in the intestinal tract of higher mammals, thus it is considered a useful biomarker associated with the faecal matter of animals such as humans and pigs. The concentration of these compounds was greater during the time period in which the pigs were undergoing the putrefaction stage of decomposition, at which point fluids would be leeching into the soil. This suggests a certain time frame in which these compounds are useful as indicators of decomposition fluids.

chol

Cholesterol

The research suggested that, as the cadaver decomposes, decomposition fluids leak into the soil, depositing cholesterol and coprostanol (and a whole range of other substances). Thus the presence of these compounds in a particular area of soil, particularly if nearby similar areas did not contain them, could indicate previous decomposition of a human (or equally a pig or other animal) in the area. However it is vital to note that these compounds could equally be detected in the soil as a result of faecal matter, though potentially in considerably lower concentrations than those produced by a whole decomposing body.

Other compounds resulting from decomposition are of equal interest in detecting potential gravesites. Adipocere, also known as grave wax, is an insoluble, white substance known to form if a body decomposes in very specific conditions. The presence of this substance in soil can of course indicate the decomposition of a body, but how does one distinguish between the decomposition fluids of a human and those of another mammal? Research has aimed to answer this question using isotopes (Bull et al, 2009). By focusing on the ratio of 13C to 12C content of particular fatty acids from the fats of various animals, it was suggested that it is possible to distinguish between adipose fats from humans and those from other animals, such as pigs, though further work may be required to develop this application.

Other researchers are applying existing forensic techniques in a novel manner to the detection of clandestine graves. When the body decomposes, a significant amount of nitrogen is released, typically in the form of ammonium and nitrate (Hopkins et al, 2000). Ninhydrin, a compound already readily available to law enforcement due to its use as a method of fingerprint development, can produce a blue or purple pigment upon reaction with certain nitrogen-containing compounds.

nin

Ninhydrin is typically used for visualising fingerprints (http://daten.didaktikchemie.uni-bayreuth.de)

One particular study examining ninhydrin reactive nitrogen (Carter at al, 2008) left a number of mammalian cadavers to decay over a period of a month, after which soil samples from the burial sites were collected and analysed for ninhydrin reactive nitrogen. This work discovered that cadaver burial resulted in the concentration of NRN in the soil approximately doubling, thus concluding that it may be possible to use ninhydrin as a presumptive test for gravesoil. Of course this particular method is somewhat limited by the fact that any mammalian cadaver (and plants or faeces for that matter) will most likely produce this increase in nitrogen-containing compounds which will react with ninhydrin, but an interesting application of an existing indicator nonetheless.

The various methods of using the chemical analysis of soil to detect clandestine graves are plentiful and fascinating. Despite the limitations, namely the possibility of animal faeces and non-human decomposition providing false positive results, these techniques may at the very least act as a kind of presumptive or complimentary test for possible burial sites.

References

Von der Luhe, B. Dawson, L. A. Mayes, R. W. Forbes, S. L. Fiedler, S. Investigation of sterols as potential biomarkers for the detection of pig (S. s. domesticus) decomposition fluid in soils. Forensic Sci Int. 230 (2013), pp. 68-73.

Bull, I. D. Berstan, R. Vass, A. Evershed, R. P. Identification of a disinterred grave by molecular and stable isotope analysis. Sci Justice. 49 (2009), pp. 142-149.

Carter, D. O. Yellowless, D. Tibbett, M. Using ninhydrin to detect gravesoil. J Forensic Sci. 53 (2008), pp. 397-400.