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The correlation between the Aquatic Decomposition Score (ADS) and the post-mortem submersion interval measured in Accumulated Degree Days (ADD) in bodies recovered from fresh water


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The Aquatic Decomposition Score (ADS) made by van Daalen et al., was developed to approximate the Post-Mortem Submersion Interval (PMSI) in bodies recovered in salt water. Since the decomposition process in salt water differs from the process in fresh water due to salinity, the temperature, and the depth of the water, we wanted to investigate whether there is a correlation between the ADS and the PMSI and if the ADS can be used to make an estimation of the PMSI in bodies recovered from fresh water. For the latter, the PMSI was measured using Accumulated Degree Days (ADD). In our study we included seventy-six human remains found outdoors in fresh water. Their decomposition was measured using the ADS. A strong correlation was found between the ADS and the PMSI. Also, it was found that the ADS can significantly estimate the ADD. Despite the more varied circumstances under which bodies in fresh water are found when compared to those found in salt water, the ADS can be used to measure the decomposition and accurately estimate the ADD, and thus the PMSI. More research is needed to validate our method and make a prediction model with smaller confidence intervals.
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Forensic Science, Medicine and
ISSN 1547-769X
Forensic Sci Med Pathol
DOI 10.1007/s12024-018-9987-5
The correlation between the Aquatic
Decomposition Score (ADS) and the post-
mortem submersion interval measured in
Accumulated Degree Days (ADD) in bodies
recovered from fresh water
Guido Reijnen, H.Tamara Gelderman,
Bernice F.L.Oude Grotebevelsborg, Udo
J.L.Reijnders & Wilma L.J.M.Duijst
1 23
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The correlation between the Aquatic Decomposition Score (ADS)
and the post-mortem submersion interval measured in Accumulated
Degree Days (ADD) in bodies recovered from fresh water
Guido Reijnen
&H. Tamara Gelderman
&Bernice F. L. Oude Grotebevelsborg
&Udo J. L. Reijnders
Wilma L. J. M. Duijst
Accepted: 18 April 2018
#Springer Science+Business Media, LLC, part of Springer Nature 2018
The Aquatic Decomposition Score (ADS) made by van Daalen et al., was developed to approximate the Post-Mortem
Submersion Interval (PMSI) in bodies recovered in salt water. Since the decomposition process in salt water differs from the
process in fresh water due to salinity, the temperature, and the depth of the water, we wanted to investigate whether there is a
correlation between the ADS and the PMSI and if the ADS can be used to make an estimation of the PMSI in bodies recovered
from fresh water. For the latter, the PMSI was measured using Accumulated Degree Days (ADD). In our study we included
seventy-six human remains found outdoors in fresh water. Their decomposition was measured using the ADS. A strong corre-
lation was found between the ADS and the PMSI. Also, it was found that the ADS can significantly estimate the ADD. Despite
the more varied circumstances under which bodies in fresh water are found when compared to those found in salt water, the ADS
can be used to measure the decomposition and accurately estimate the ADD, and thus the PMSI. More research is needed to
validate our method and make a prediction model with smaller confidence intervals.
Keywords Post-mortem submersion interval .Decomposition .Aquatic Decomposition Score .Accumulated Degree Days .
Drowning .Fresh water
Drowning is a manner of death which occurs frequently all
over the world. According to the World Health Organization,
every year 360,000 people drown [1]. The circumstances un-
der which people drown can be accidental, suicidal, or even
homicidal. The post-mortem submersion interval (PMSI), the
time between death and the recovery of human remains from
the water, is of great importance in the reconstruction of the
events that led to death.
Multiple methods have been developed to estimate the
PMSI. Methods involving the natural growth of biofilms con-
taining algal, bacterial, fungal and protozoan species have
been investigated and are promising [24]. Unfortunately,
most of these methods require intensive laboratory analysis
and thus they are not able to estimate the PMSI at the scene
of the recovery. Another method used to estimate the PMSI
involves measuring the degree of decomposition of the recov-
ered human remains. For example, the Total Decomposition
Score (TDS) method was developed for human remains found
*Guido Reijnen
H. Tamara Gelderman
Bernice F. L. Oude Grotebevelsborg
Udo J. L. Reijnders
Wilma L. J. M. Duijst
Amsterdam Public Health Service, Amsterdam, The Netherlands
Rijnstate Hospital Arnhem, Arnhem, The Netherlands
IJsselland Public Health Service, Zwolle, The Netherlands
Netherlands Forensic Institute (NFI), The Hague, The Netherlands
Faculty of Law and Criminology, Maastricht University,
Maastricht, The Netherlands
Forensic Science, Medicine and Pathology
Author's personal copy
on land [5]. This method used for bodies found on land was
adjusted for bodies found in water by Heaton et al. [6]. The
Aquatic Decomposition Scoring (ADS) method of Heaton et
al. has been the subject of much research [6]. Humphreys et al.
compared Heatons ADS method with the mass analysis
method and found the former was the more accurate and the
less compromising method for determining and evaluating the
level of decomposition for human remains found in fresh wa-
ter [7]. De Donno et al. also studied Heatons ADS method
and found it promising, but concluded that determining the
PMSI is still extremely difficult due to wide biological vari-
ability [8].
However, the adjusted scoring method for bodies found in
water has not been validated. Recently, van Daalen et al. de-
veloped the Aquatic Decomposition Scoring (ADS) method
to estimate the PMSI of bodies recovered from salt water [9].
This method was derived from Megyesi et al. [5], who quan-
tified the stage of decomposition of bodies recovered from
open air in a total decomposition score. This score is based
on the decomposition stages of three different areas of the
body: the face and neck; the body; and the limbs. The van
Daalen et al. [9] ADS divides the body in the same manner.
The Total Aquatic Decomposition Score (TADS) is the com-
bined scores for these three areas. The ADS describes specific
aquatic decomposition phenomena divided into six stages. A
validation test was carried out with high outcomes. The ADS
method developed by van Daalen et al. [9] differs from the one
developed by Heaton et al. [6]. Instead of a maximum TADS
of 25, van Daalens ADS has a maximum TADS of 18. In the
ADS method of van Daalen et al., phenomena are added to-
gether in one stadium, while in Heaton et al.s they are given
their own score [6,9].
The literature shows that the salinity of water greatly influ-
ences the decomposition process. For example, a high saline
concentration in water reduces the bacterial activity [8,10,11].
Temperature also influences the decomposition process, as the
process is accelerated in warmer waters [6]. The temperature
of the water is influenced by depth, since sunlight rarely pen-
etrates deeper than two meters [6]. Depth also influences de-
composition itself. When a body isbelow a certain water depth
(approximately 61 m), bloating does not occur (due to high
pressure) and thus the body will not float or wash ashore
[1214]. The more varied levels of decomposition of human
bodies recovered from fresh water may adversely affect the
accuracy of the decomposition score.
In recent years, multiple studies have investigated the use of
ADD and TADS to calculate or estimate the PMSI [7,8]. The
ADD is the sum of the average daily ambient temperatures
between the date of death and the date of recovery. It represents
the heat energy units needed for the biological and chemical
reactions to decompose a body [15]. The ADD has not (yet)
been used to estimate the PMSI with the ADS developed by
vanDaalenetal.[9] for bodies recovered in fresh water.
This study describes the correlation between the ADS de-
veloped by van Daalen et al. [9]and the PMSI and between
the TADS and the ADD (and thus the PMSI) in bodies recov-
ered from fresh water.
In this retrospective study, bodies recovered from outdoor
fresh water in Amsterdam, the Amsterdam region, and the
IJsselland region, all located in the Netherlands, between
March 2008 and July 2017 were included. Fresh water was
defined as water having a sodium chloride content of less than
nine grams per liter.
All included cases of bodies recovered from water were
closed, which means there was no ongoing (criminal) inves-
tigation at the time of data analysis. For the body to be includ-
ed, the personal data of the deceased person had to be known
and a post-mortem report had to be available. This included a
known PMSI and full color photographs of the face, limbs and
the body. Children under the age of 18 years were excluded
because their body surface area body content ratio is higher
compared to that of adults [16]. Moreover, children have a
different distribution of body surface area due to their propor-
tionally larger heads and smaller lower extremities [17].
Bodies recovered from indoor fresh water were also excluded.
Seventy-six cases were included, of which there were 61
males (80.3%) and 15 females (19.7%). The mean age was
52 years with a minimum of 18 and a maximum of 83. The
types of water in which the human remains were found in-
cluded ditches (n=13),canals(n= 14), channels (n= 9), riv-
ers (n= 19), ponds (n= 6), puddles (n= 4), lakes (n= 5), other
(n= 1) and unknown (n= 5). Thirty-five individuals passed
away after an accident and 26 after committing suicide. In
15 cases, the manner of death was unknown.
Measuring decomposition
The decomposition scoring method of van Daalen et al. [9]
was used to measure the level of decomposition. This decom-
position scoring method divides the sequential pattern of the
decomposition process into six stages, each containing specif-
ic phenomena. The human body is divided into three anatom-
ical regions (face and neck, body, and limbs). Each region can
be appointed a value from 1 to 6. The TADS is equal to the
sum of these three values. A score of 3 means no visible
changes and a score of 18 means complete skeletonization.
To guide the users of the decomposition scoring method, an
explanation of the decomposition stages and phenomena has
been developed, as well as a pictorial reference atlas. The
reference atlas contains photographic examples of all the phe-
nomena occurring in the decomposition process.
Forensic Sci Med Pathol
Author's personal copy
Measuring TADS
A senior forensic physician, with no experience with this
method outside the received verbal instructions described be-
low, scored all 76 included cases. This forensic physician had
no knowledge of the cases, so the scoring was blinded to
prevent bias. Previous research has shown that the ADS has
a strong agreement between scorers (who ranged from medi-
cal doctors to police officers). The Krippendorffs alpha scores
were between 0.93 and 0.96, where scores over 0.80 are con-
sidered to be high [9,18]. Because of this strong agreement,
scoring in this study could be done by one forensic physician.
Before scoring any of the 76 cases, the forensic physician
received verbal instructions regarding the decomposition scor-
ing method and how to use the pictorial reference atlas. The
forensic physician was instructed to start with the highest
stage and work his way down, until the decomposition stage
containing the visible phenomena was reached. When multi-
ple phenomena were present, the highest score was to be re-
corded. After the three anatomical regions were scored by the
forensic physician, the TADS was calculated by the
Measuring ADD
The ADD is the sum of the mean daily water temperatures
between the time of death and the recovery date. The water
temperature data was provided by the executive agency of the
Ministry of Infrastructure and Water Management
(Rijkswaterstaat) [19]. Because we had to deal with different
water types and many different locations, we chose to use the
water temperature from two points in the Amsterdam region.
For the bodies found between 2008 and 2013, we used record-
ings near the Amsterdam IJtunnel. These recordings were
made approximately 1 to 3 times per month. From the years
2013 up to and including 2017, there were daily recordings of
the water temperature at the former NDSM shipyard (approx-
imately 2.5 km north-west of the IJtunnel recordings).
The ADD was calculated by adding up the average daily
water temperatures from the date the body was found back to
the date of death.
Statistical analysis
The statistical analysis was conducted using SPSS, version
24.0 (SPSS Inc.) and Software R and R studio. The
Spearman correlation coefficient was used to test the correla-
tion between the aquatic decomposition score and the PMSI.
The ADD and TADS were used to produce a linear regression
model with the ADD as the independent variable. We trans-
formed the ADD with the logarithm (log 10). The TADS was
rescaled from 3 to 18 to 015 by subtracting 3. Software R and
R studio was used to make estimates of the ADD with
prediction intervals for every TADS score using inverse pre-
diction. The statistical method is based on Moffat et al. [20].
This study was approved by the Public Health Service
Amsterdam and the Public Health Service IJsselland and per-
formed according to the ethical and legal standards in the
Netherlands. All data were processed anonymously.
Baseline characteristics
In the research population, the TADS rescaled ranged
from 0 (no visible changes) to 10 (extensive decomposi-
tion). In 42 cases there were no visible changes, in 9 cases
there was one decomposition phenomenon visible, and in
25 cases there were two or more decomposition phenom-
ena visible.
The ADD ranged from 3.7 to 6245.8. Twenty cases had an
ADD below 10. Forty-four cases had an ADD between 10 and
100, nine between 101 and 1000 and three cases had an ADD
higher than 1001. The last three cases, with an ADD of
1259.0, 1398.7 and 6245.8 respectively are considered to be
outliers, but were not removed from the analysis because they
are part of daily practice. The fourth highest ADD is 611.6.
TADS versus PMSI
The correlation between the decomposition and PMSI was
measured for the three body regions separately and for the
combination of these (TADS). The highest correlation was
found between LADS and the PMSI, followed by the corre-
lation between TADS and PMSI (Table 1). The correlation
between FADS and PMSI was very close to the correlation
Table 1 ADS versus PMSI
Spearmans rho FADS 0.754 <0.001
BADS 0.754 <0.001
LADS 0.846 <0.001
TADS 0.818 <0.001
ADS as made by van Daalen et al.
PMSI Post-Mortem Submersion Interval, FA D S Facial Aquatic
Decomposition Score, BADS Body Aquatic Decomposition Score,
LADS Limbs Aquatic Decomposition Score, TADS Total Aquatic
Decomposition Score, p = p-value
Forensic Sci Med Pathol
Author's personal copy
between BADS and PMSI. Although the lowest correlation is
0.754, this is still considered a strong correlation [21].
Correlation between TADS and ADD
The correlation between decomposition (TADS) and ADD
was measured and was strong (N= 76, Spearmansρ=
0.707, p<0.001)[21]. The TADS can be used to predict the
ADD using the following formula:
TADS rescaled ¼4:055 x Log ADDðÞ3:836:
This model fits the data well (R
= 0.782); the regression
line is shown in Fig. 1.
We have developed a prediction model with an estimated
ADD with a confidence interval for every TADS. Table 2
shows the values of the confidence interval. These values
were log transformed to make Fig. 2.
As previously mentioned, bodies recovered from fresh wa-
ter are exposed to different variables compared to bodies
recovered from salt water [8]. The aim of this study was to
investigate whether the recently published ADS developed
by van Daalen et al. [9] can also be used to measure de-
composition for bodies recovered from different types of
fresh water and to make a correlation with the PMSI. We
decided not to exclude the outliers because they are part of
daily practice. We realize that this makes our outcomes
potentially less favorable than they would be if the outliers
were excluded.
Our results showed a strong correlation between the FADS
and BADS with the PMSI and a very strong correlation
between the LADS and TADS with the PMSI. We conclude
that the ADS can be used for measuring the degree of decom-
position in bodies recovered from fresh water.
The TADS is strongly correlated with the ADD, despite our
heterogeneous population with outliers. An advantage of the
ADS compared with other decomposition scores is that the
decomposition can be scored at the scene of the recovery
and no autopsy is required. Another advantage of this method
is that it is less time consuming than other methods, such as
Fig. 2 Log confidence interval lines per TADS. TADS Total Aquatic
Decomposition Score, ADD Accumulated Degree Days, CI
Confidence Interval
Table 2 TADS and predicted ADD using inverse prediction
TADS rescaled Predicted ADD Lower 95% CI Upper 95% CI
0 8.8 2.1 37
2 27.5 6.6 114.6
4 85.6 20.4 359.8
5 151 35.6 640.8
6 266.4 62 1145
7 470.1 107.6 2053
8 829.5 186.3 3692
9 1464 321.6 6660
10 2582 553.4 12,048
11 4556 949.9 21,855
12 8039 1626 39,745
13 14,185 2777 72,458
14 25,028 4731 132,399
15 44,161 8044 242,449
TAD S Total Aquatic Decomposition Score, ADD Accumulated Degree
Days, CI Confidence Interval
Fig. 1 Plot of Total Aquatic Decomposition Score vs. Log transformed
Accumulated Degree Days. R
=0.782 (n=76)
Forensic Sci Med Pathol
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those involving the natural growth of biofilms, and no specific
expertise is needed [2,3,22].
We conclude that for bodies recovered from fresh water,
there is a correlation between the TADS and the ADD. The
strength of this study is that cases from different types of water
were included and these cases are from a general forensic
practice. What makes this model especially useful in practice
is that the water temperature of a general measuring point can
be used. Thus the model can be used even if the temperature of
the water in which a deceased person is found is unknown.
Future research could compare van Daalens ADS method
to other methods to investigate the accuracy of both methods.
Validating other methods by using this method is discouraged,
however, since there are limitations of this study which need
to be addressed first.
This research has certain limitations. It is a retrospective
study and the scoring is based on photographs. Some cases
lacked sufficient photographs of certain body parts. In some
cases, only pictures of the divergences were made, while the
other parts of the body were not recorded in detail. The ab-
sence of pictures from these parts can potentially lead to an
underestimation of the TADS. In a prospective study, when
scoring is performed on site, this limitation can be avoided.
Bodies with no visible decomposition are relatively over-
represented in our general practice (N=42(55.3%),TADS=
3). Most of these individuals were reported missing and found
soon after a search was started. In other cases, bystanders saw
individuals going for a swim, for example, but they never
returned or a body was seen floating in the water. In these
cases, emergency aid was started quickly and the remains
were not in the water long enough for decomposition phenom-
ena to become visible.
Unfortunately, there were 58 cases (76.3%) with an ADD
between 0 and 50. Future prospective studies would benefit
from more cases with a higher ADD and advanced decompo-
sition and also to validate the results found in this research.
The exclusion of outliers should be avoided because they are
present in the daily practice.
In this study there was no differentiation made between
complete submersion and partial submersion. In some cases,
the body was partially exposed to air, either because the water
was shallow or the body was already floating as a result of
ongoing decomposition. As decomposition on land differs
from decomposition in water [23], the exposure to air could
have an influence on the TADS in our study.
Humphreys et al. [7] tested the TADS method developed
by Heaton et al. [6] and found a different logarithmic re-
gression line compared to the one found by Heaton et al.
The authors mention that this was expected because the
methods in the two studies differed from each other (human
remains vs. perinatal piglets and U.K. waterways vs. agri-
cultural reservoir); however, it should be stated that their
regression line is based on a natural logarithm (with a base
of 2.7) instead of the base 10 logarithm used by Heaton et
al. [6]. The authors also described the need to determine the
appropriate ADD and TADS equation for every location in
which human remains are found. In our study we have de-
veloped one model that fits for multiple locations and types
of water in the Netherlands using a general water tempera-
ture measurement point.
In addition to the correlation previously found between van
Daalens ADS and the PMSI in bodies recovered from salt
water, there is a strong correlation between van Daalens
ADS and bodies recovered from fresh water. Thereby, there
is also a strong correlation between the ADS and the ADD of
bodies recovered from fresh water. These correlations were
found despite the various circumstances under which bodies
were found in fresh water compared to those found in salt
water. We conclude that the ADS is usable in measuring the
decomposition and in a prediction model to accurately predict
the ADD for bodies recovered from fresh water. More re-
search is needed to validate this model with use of future cases
and to make a prediction model with smaller confidence
Key points
1. There is a strong correlation between the Aquatic
Decomposition Score and the Accumulated Degree Days.
2. The Aquatic Decomposition Score can be used to predict
the time of death in bodies recovered from fresh water.
3. The Aquatic Decomposition Score is applicable under
various circumstances.
4. More research is needed to make a more accurately pre-
diction model using the Accumulated Degree Days.
Acknowledgments The authors would like to thank Mr. W Heutz (inde-
pendent forensic physician) for scoring the 76 cases.
Funding This research did not receive any specific grant from funding
Compliance with ethical standards
Conflict of interest The authors declare that they have no conflict of
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... Estimating the time of death using ADD-based methods can also provide a correct assessment in advanced stages of decomposition in which pathological parameters cannot estimate the minimum PMI [15,[17][18][19]. Thus, quantitative approaches (ADD and body scoring methods) too have been extensively used [20][21][22][23][24] and validated [21,23,[25][26][27][28]. One of the premier studies developed by Megyesi et al. [20] involved an assessment method to record the decomposition process, which divided the entire body into three areas: (i) the head and neck area, (ii) trunk area, and (iii) limbs followed by a summary of these points in the form of the total body score (TBS). ...
... Similarly, Fink [28] studied 73 forensic cases collected from different medical examiners' offices and calculated the PMSI using ADD estimates developed by Megyesi et al. [20] and Heaton et al. [21] ranging the ADD between 0.01°C and 1826.5°C with a mean ADD and showed similarity with research that studied the correlation between the ADDs calculated using two different methods [23,[26][27][28]40]. ...
... The correlation studied has shown a significant effect between ADD and TADS, as found in the current study. Like Reijnen et al.'s[26] study, TAD scores and the actual ADD showed a significant correlation (r 2 = 91.71%). The actual and the estimated ADD also showed a significant correlation (r = 0.9585) ...
Investigating drowning-related deaths remains a significant problem for forensic personnel all over the world. The previously published decomposition scoring method like the total aquatic decomposition (TAD) score promises to estimate the correct post-mortem submersion interval (PMSI) in aquatic habitats through the assessment and calculation of the decomposition rate and accumulated degree days (ADD). The current study comprised of 53 drowned death cases belonging to various districts of Haryana from May 2016 to August 2017. The regression and Pearson's correlation indicated a significant correlation between the TAD scores and the actual ADD (calculated through water temperatures) (r2 = 0.917) and between the actual and the estimated ADDs (calculated through TAD scores used by Heaton et al. [21]) (r = 0.9585). The results indicated that the estimated ADD tends to over predict the PMSI compared to the actual ADD. It is further confirmed by paired t-test, which showed the mean of actual ADD (mean = 349) to be significantly lower than the mean of estimated ADD (mean = 663). Moreover, these methods will help forensic investigators and researchers formulate region-specific regression equations for PMSI estimation.
... As PMSI (days) and ADD showed a non-parametric distribution, the Spearman Rank determination coefficient was calculated to determine whether PMSI or ADD correlated with the TADS. As performed in previous studies [16,21,25], the ADD was log-transformed (log 10) to fulfil the requirement of a linear relationship and a normal distribution when performing linear regression analysis to investigate the relationship between ADD and TADS. Therefore, a regression analysis was conducted in order to produce an equation for each model and determine which better fits the variation in decomposition. ...
... The regression analysis confirmed the results of the t-test performed between PMSI, ADD and TADS of corpses recovered in the cold and in the warm season, which failed to demonstrate significant differences. The low influence of water temperature on the prediction model might be due to the salinity, that slows down the putrefaction processes even at higher temperatures [4,25,27]. However, this hypothesis should be confirmed with further studies that include a higher sample size and bodies recovered in different geographical areas. ...
Purpose The decomposition process of human bodies in marine environment is not well understood, and it is influenced by external variables related to the geographical area where the body is submerged. We report the application of two decomposition scores, the Heaton’s score and the van Daalen’s score, on a casuistry of human bodies recovered from the Northern Adriatic Sea. The aims of this study are to verify whether the marine environment of a Mediterranean climate area may affect the applicability of both scores and to develop a prediction model that can be applied on bodies recovered in salt water. Methods A retrospective study was performed on 61 human bodies recovered between 2005 and 2019 from coastal water of the Northern Adriatic Sea nearby the Italian regions Emilia-Romagna and Marche. For each of the 61 cases included, the Total Aquatic Decomposition Score (TADS) was calculated with the Heaton’s score and the Van Daalen’s score. The prediction model was assessed through multiple regression analyses, and the determination coefficients (r²) between TADS and PMSI (expressed in days) and between TADS and Accumulate Degrees Days (ADD) were studied. The prediction model was applied to the entire case sample, to bodies recovered during the warm season and to bodies recovered during the cold season. Results All bodies were recovered floating, and a very poor scavenging activity was observed. The regression analyses showed a strong correlation between the TADS and the total case sample using both scores and both independent variables (PMSI and ADD). The determination coefficients were greater than 0.95 also when considering the total case sample. Discussion The proposed prediction models are not significantly influenced by seasonality, contrarily to what observed on bodies recovered in fresh water in the same climate area. However, the ADD model, which also consider the water temperature, should be preferred for higher decomposition stages. This study helps increase the accuracy of PMSI estimation in bodies recovered from a marine environment of the Northern Adriatic Sea.
... The movement of drowned bodies through water, and the various related characteristics of that movement are also of interest to forensic investigators, leading potentially to the identification of missing people or leading searchers to locate drowned victims faster and more efficiently (Byard, 2018;Mateus et al., 2013;Reijnen et al., 2018) Clearly, functions of water movement, through currents or flows and a body's specific gravity (SG) (combining physical characteristics, levels of gas within the body and additional items such as clothing) determine how fast, in what direction and at what depth a body is suspended. ...
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This paper catalogues a dataset drawn from Metropolitan Police records in the period 2004-2015 regarding drowning victims recovered from a tidal stretch of the River Thames and provides a comparative study with a similar dataset from the time period 1956-1959 by the County of London (Western District), H.M. Coroner of that time, Gavin Thurston, from the information gathered in his professional role. In addition to drawing comparisons between these time periods the paper draws inferences regarding the Post-Mortem Submersion Interval (PMSI) and proposing further study required. Both datasets show a significant bias towards male subjects counter to other comparable data in the literature. This bias is even more pronounced in the 2004-2015 period where additionally there are significantly more incidents during Full Moon Lunar Phase. Some weak seasonal trends were observed regarding equinoctial peaks but these were not statistically significant. There are few clear trends observable in factors that might influence Post-Mortem Submersion Interval although there was a weak and counter-intuitive inverse relationship between clothing weight and time in water.
... El método del cálculo de intervalo de inmersión comunicado por Heaton resultó novedoso y fue validado por otros autores en otras localizaciones [8][9][10] , sin embargo fue cuestionado desde lo metodológico por los errores relacionados con el redondeo, la escala de temperatura y el uso incorrecto de un modelo de regresión estadística que hacen que su fórmula predictiva sea inutilizable 8 . Del mismo modo, otros autores como De Donno 11 tomaron con cautela el método de la ADG en cuerpos recuperados del agua para estimar el intervalo de inmersión, argumentando que el mismo puede dar una falsa percepción de precisión debido a la complejidad de integrar todos los factores cambiantes que afectan la descomposición humana en ambientes acuáticos tales como corrientes, actividad animal, temperaturas del agua, profundidad de inmersión, edad, tamaño, y vestimenta la cual puede alterar la temperatura cadavérica 9-12 . ...
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Introducción: la estimación del tiempo de inmersión de cuerpos recuperados del agua, mediante la valoración de los cambios cadavéricos permiten inferir el tiempo que han permanecido en el agua independientemente de la causa de la muerte. En el presente estudio se analiza el método de Acumulación Diaria de Grados (ADG) para el cálculo de intervalo de inmersión en cuerpos recuperados del agua, en 36 cuerpos con intervalo de permanencia en el agua conocido. Material y métodos: sobre un total de 161 cuerpos recuperados del agua entre 2007 y 2022, en 41 casos se contaban con datos para ser analizados mediante el método de ADG y 36 fueron aptos para realizar el análisis del método al confrontarlos con los intervalos conocidos de inmersión de los cuerpos. Resultados: la comparación del cálculo por ADG versus el intervalo de inmersión conocido, de la muestra de 36 casos, resultó que la diferencia de cifras en días obtenidas es estadísticamente significativa (p= 0,48 > 0,005). En 16 casos (44,4%) hubo una subestimación por el método de ADG con respecto al tiempo de permanencia en el agua conocido que difería en un promedio del 40%, y en 18 casos (50%) una sobreestimación del 41%. Con base en la observación de los cambios cadavéricos, el mes del año y la temperatura del medio líquido, se confeccionó una tabla para la estimación del intervalo postmortal de inmersión para cursos de agua de la Patagonia Norte. Conclusión: el método de ADG en cuerpos recuperados del agua para estimar el intervalo de inmersión, puede dar una falsa percepción de precisión debido a la complejidad de integrar todos los factores cambiantes que afectan la descomposición humana en ambientes acuáticos. n 2022 Asociación Nacional de Médicos Forenses. Publicado por Elsevier España, S.L.U. Todos los derechos reservados.
... In 2017, van Daalen et al. developed another aquatic decomposition scoring (ADS) method to estimate PMSI of cadavers recovered from salt water, describing specific aquatic decomposition phenomena. Reijnen et al. (2018) investigate if van Daalen et al. (2017) ADS method could be used to estimate PMSI in bodies recovered from fresh water, since decomposition may be affected by salinity or water depth. They have concluded that this method can be accurately used in cadavers discovered in fresh water, emphasizing, however, that bodies found in this context are exposed to more diverse conditions that the ones found in salt water. ...
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The estimation of the postmortem interval (PMI), particularly the late time since death, is a crucial issue when dealing with human remains. Its establishment is an important task for forensic scientists since it has important legal implications such as identifying a victim or prosecuting an offender. However, dating death is a very complex and challenging task due to the amount of intrinsic and extrinsic factors, that may influence the rate and nature of body decomposition. Many methods have been used to estimate PMI, from classical decomposition methods to entomological and botanical methods or more recently physics and biochemical methods. This paper reviews current forensic dating methods, focusing especially on forensic anthropological techniques. Nevertheless, the existing literature is insufficient, denoting a lack of effective methods to achieve an accurate and reliable PMI estimation and further investigation is required. A holistic approach, where every element must be considered, is the key to achieving a reliable estimation of PMI. Interdisciplinarity is thus mandatory, allied with the capacity of forensic anthropologists to denote all the details.
... Predicting locations of mortality sources requires understanding of both taphonomic processes and the environmental factors that influence decomposition, as well as the dispersal and persistence of carcasses. Although there have been numerous studies on human (Mateus & Pinto 2016, Reijnen et al. 2018) and animal decomposition (Anderson & Hobischak 2004, Anderson & Bell 2014, few researchers have studied decomposition of marine animals or sea turtles in particular (Santos et al. 2018). Using cadaver studies and robust sample sizes, we show that both depth and water temperature significantly influence sea turtle decomposition, which has considerable bearing on the dispersal of dead sea turtles and thus probability of discovery. ...
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When a sea turtle dies, it typically sinks to the bottom, begins decomposing, and floats to the surface once sufficient internal gases have accumulated to produce positive buoyancy. This process is poorly characterized and is essential to understanding where and when sea turtles found on shore may have died. We conducted decomposition studies with detailed time-temperature histories using carcasses of cold-stunned sea turtles (22 Kemp’s ridleys Lepidochelys kempii and 15 green sea turtles Chelonia mydas) at temperatures of 14-32°C and depths of 2.2-9.5 m. We found strong depth/pressure-related effects; carcasses took longer to float when incubated at greater depths than shallower depths at similar temperatures. Furthermore, carcasses incubated at colder temperatures (~15°C) took 8 times longer to float than those at 32°C at the same depth. We applied accumulated degree hours (ADH; hourly sum of ambient temperatures a carcass experienced) to characterize environmental conditions associated with different stages of decomposition and key events, including buoyancy and sinking. A formula for temperature-correction of ADH was calculated to fit a non-linear increase in decomposition at higher temperatures. These data were then used to improve an existing backtracking model by incorporating water temperature, depth (pressure), bathymetry, and postmortem condition. Heat maps of the probable mortality locations from the model agreed well with carcass and effigy drift experiments, demonstrating the overall reliability of the enhanced model. Our method can be used to estimate at-sea locations where sea turtles found washed ashore in the northern Gulf of Mexico likely died and may help inform similar efforts in other regions.
... Over the years, multiple methods have been developed and published to estimate the PMI using decomposition [94][95][96][97][98][99][100][101][102]. Most of the decomposition scoring methods use temperature in the form of Accumulated Degree Days (ADD) to estimate the PMI [95][96][97][98][99]101]. ...
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When a capital crime is committed the post-mortem interval (PMI) is of particular importance in investigating a suspect’s alibi in court. A forensic expert can use different methods to estimate the PMI. This research focuses on who is considered an expert in court and whether the methods used to estimate the PMI are reliable. In this study, the methods used to estimate the PMI and the experts consulted, available in Dutch jurisprudence, in the period 2010–2019 were investigated. Ninety-four judicial cases were included and multiple experts and methods of estimating the PMI were found. As part of this study, the methods that were used to estimate the PMI in court were subjected to the Daubert criteria. Of these methods, only the Henssge nomogram and entomological methods met the Daubert criteria. However, the methods are only useful when applied by the right forensic expert and in the right manner. Unfortunately, this was not always the case.
... The model fit for surface cases is higher in this study than in studies conducted in Swedish indoor settings (r 2 = 0.54) [40,42], as well as in an outdoor study in the Netherlands (r 2 = 0.56) [73], while similar to the model fit achieved by Megyesi et al. [17] in the United States (r 2 = 0.84). The model fit for aquatic cases was lower in the current study than that achieved in the UK by Heaton et al. ...
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This paper presents a quantitative retrospective study of gross human decomposition in central and southeastern Sweden. The applicability of methods developed abroad for postmortem interval (PMI) estimation from decomposition morphology and temperature are is evaluated. Ninety-four cases were analyzed (43 terrestrial and 51 aquatic) with a median PMI of 48 days. The results revealed differences in decomposition patterns between aquatic, surface, hanging, and buried remains. While partial saponification and desiccation occurred in cases of surface remains, complete skeletonization was observed in all cases with a PMI over two years. Aquatic skeletonization was slower due to extensive saponification in cases with PMI higher than one year. Formulae for assessing accumulated degree-days (ADD) from the original methods did not fit the study material. However, a regression analysis demonstrated that 80% of decomposition variance in surface remains could be explained by ADD, suggesting that a geographically adapted equation holds promise for assessing PMI. In contrast, the model fit was poor for aquatic cases (43%). While this may be explained by problems in obtaining reliant aquatic temperature data or an insufficient scoring system, aquatic decomposition may be highly dependent on factors other than ADD alone. This study evaluates the applicability of current PMI methods on an outdoor sample from a previously unpublished region, and represents the first scientific publication of human outdoor decomposition patterns in Sweden. Suggestions for future research are provided, including that scoring methods should incorporate saponification to fit forensic taphonomy in Swedish environments.
Drowning is the third leading cause of accidental death globally, however, many individuals who lose their lives at sea are never recovered or identified. Along with the geographic challenges posed by the underwater environment, environmental conditions influence the degradation and preservation of submerged remains. Understanding how human bodies decompose in the marine environment can assist with more accurate estimations of the postmortem submersion interval, reconstruction of the postmortem history, and determination of the original deposition environment, as well as prepare recovery teams and their families for what to expect upon locating the deceased in a marine environment. In this review, previous research surrounding human remains in the marine environment is reviewed with a focus on the factors that will influence decomposition of the human body from initial submergence to skeletonization. Experimental research, retrospective analyses, and case studies are brought together in this paper to demonstrate the currently available knowledge on marine decomposition. It is suggested that further systematic research is necessary to create robust evidentiary standards to develop context-specific knowledge on which to base future forensic investigations and assist with the recovery and identification of submerged individuals.
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The taphonomy of carcasses submerged in the ocean is little understood, yet it is extremely important ecologically and forensically. The objectives of this study were to determine the fate of pig carcasses as human proxies in the Strait of Georgia at 170 m in spring and fall. Using Ocean Networks Canada’s Victoria Experimental Network Underseas (VENUS) observatory, two carcasses per season were placed under a cabled platform hosting a webcam and instruments measuring water chemistry. Two minutes of video were recorded every 15 min. In spring, Lyssianassidae amphipods and Pandalus platyceros were immediately attracted and fed on the carcasses, the amphipods removed the bulk of the soft tissue from the inside whilst the shrimp shredded the skin and tissue. The carcasses were skeletonized on Days 8 and 10. In fall, Metacarcinus magister was the major scavenger, removing most of the soft tissue from one carcass. Amphipods did not arrive in large numbers until Day 15, when they skeletonized the scavenged carcass by Day 22 and the less scavenged carcass by Day 24. Amphipods remained for some days after skeletonization. This skeletonization was very different from previous experiments at different depths and habitats. Such data are very valuable for predicting preservation, planning recoveries, and managing family expectations.
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Megyesi et al.'s (J Forensic Sci, 2005, 50, 618) paper was important to forensic anthropology as it introduced a quantitative framework for estimating time since death in human cadavers, based upon physical appearance by way of scoring on a novel scale. However, errors concerning rounding, temperature scale, and incorrect use of a statistical regression model render their predictive formula unusable. Based upon only their more reliable data, a more appropriate regression model to predict accumulated degree days (ADD) from total body score (TBS) is presented. The new model is also a superior fit (r(2) = 0.91) and produces markedly narrower confidence intervals than the original, which also allowed impossible, negative ADD values. Explanations of the shortcomings in the original analysis and calculations are presented, which it is hoped will help forensic scientists avoid making similar mistakes.
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Biofilms are a ubiquitous formation of microbial communities found on surfaces in aqueous environments. These structures have been investigated as biomonitoring indicators for stream heath, and here were used for the potential use in forensic sciences. Biofilm successional development has been proposed as a method to determine the postmortem submersion interval (PMSI) of remains because there are no standard methods for estimating the PMSI and biofilms are ubiquitous in aquatic habitats. We sought to compare the development of epinecrotic (biofilms on Sus scrofa domesticus carcasses) and epilithic (biofilms on unglazed ceramic tiles) communities in two small streams using bacterial automated ribosomal intergenic spacer analysis. Epinecrotic communities were significantly different from epilithic communities even though environmental factors associated with each stream location also had a significant influence on biofilm structure. All communities at both locations exhibited significant succession suggesting that changing communities throughout time is a general characteristic of stream biofilm communities. The implications resulting from this work are that epinecrotic communities have distinctive shifts at the first and second weeks, and therefore the potential to be used in forensic applications by associating successional changes with submersion time to estimate a PMSI. The influence of environmental factors, however, indicates the lack of a successional pattern with the same organisms and a focus on functional diversity may be more applicable in a forensic context.
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Decomposition and faunal colonization of a carcass in the terrestrial environment has been well studied, but knowledge of decomposition in the marine environment is based almost entirely on anecdotal reports. Three pig carcasses were deployed in Saanich Inlet, BC, over 3 years utilizing Ocean Network Canada's VENUS observatory. Each carcass was deployed in late summer/early fall at 99 m under a remotely controlled camera and observed several times a day. Dissolved oxygen, temperature, salinity, density and pressure were continuously measured. Carcass 1 was immediately colonized by Munida quadrispina, Pandalus platyceros and Metacarcinus magister, rapidly scavenged then dragged from view by Day 22. Artifacts specific to each of the crustaceans' feeding patterns were observed. Carcass 2 was scavenged in a similar fashion. Exposed tissue became covered by Orchomenella obtusa (Family Lysianassidae) which removed all the internal tissues rapidly. Carcass 3 attracted only a few M. quadrispina, remaining intact, developing a thick filamentous sulphur bacterial mat, until Day 92, when it was skeletonized by crustacea. The major difference between the deployments was dissolved oxygen levels. The first two carcasses were placed when oxygen levels were tolerable, becoming more anoxic. This allowed larger crustacea to feed. However, Carcass 3 was deployed when the water was already extremely anoxic, which prevented larger crustacea from accessing the carcass. The smaller M. quadrispina were unable to break the skin alone. The larger crustacea returned when the Inlet was re-oxygenated in spring. Oxygen levels, therefore, drive the biota in this area, although most crustacea endured stressful levels of oxygen to access the carcasses for much of the time. These data will be valuable in forensic investigations involving submerged bodies, indicating types of water conditions to which the body has been exposed, identifying post-mortem artifacts and providing realistic expectations for recovery divers and families of the deceased.
Results: The river cases consisted of 43 males and seven females (M:F 6:1); age range of 2-92 years (mean 46.8 years); decomposition-16/50 (32%); postmortem interval 1-14 days, average 3.8. The sea cases consisted of 36 males and 14 females (M:F 2.6:1); age range of 9-81 years (mean 50.7 years); decomposition-2/50 (4%) (p < 0.001%); postmortem interval 1-6 days, average 2.8. As decomposition reduces information obtained at autopsy, postmortem examination of deaths in rivers may be less informative than deaths that have occurred in the sea. The reasons for less decomposition in the sea include cooler temperatures, exposure to salt and shorter postmortem intervals.
This study aimed to develop an aquatic decomposition scoring (ADS) method and investigated the predictive value of this method in estimating the postmortem submersion interval (PMSI) of bodies recovered from the North Sea. This method, consisting of an ADS item list and a pictorial reference atlas, showed a high interobserver agreement (Krippendorff's alpha ≥ 0.93) and hence proved to be valid. This scoring method was applied to data, collected from closed cases—cases in which the postmortal submersion interval (PMSI) was known—concerning bodies recovered from the North Sea from 1990 to 2013. Thirty-eight cases met the inclusion criteria and were scored by quantifying the observed total aquatic decomposition score (TADS). Statistical analysis demonstrated that TADS accurately predicts the PMSI (p < 0.001), confirming that the decomposition process in the North Sea is strongly correlated to time.
Het merendeel van de in Nederland verkrijgbare geneesmiddelen is niet geregistreerd voor gebruik door kinderen. De twee belangrijkste redenen hiervoor zijn dat de farmaceutische industrie weinig is ge?nteresseerd in het verrichten van geneesmiddelenonderzoek bij kinderen vanwege de hoge kosten en de beperkte opbrengsten, en dat onderzoek van geneesmiddelen bij vooral kleine kinderen wordt beperkt door strenge wetgeving en methodologische problemen. In Nederland geldt dat men alleen medisch wetenschappelijk onderzoek met jonge kinderen mag doen als dit onderzoek niet met ?wilsbekwame? volwassenen kan worden uitgevoerd. De afgelopen jaren is er veel discussie geweest over het wetenschappelijk onderzoek bij kinderen. Dit heeft mede geleid tot de instelling van de commissie-Doek , die kiest voor het uitgangspunt ?ja, mits?. Deze commissie vindt verder dat de eisen van een verwaarloosbaar risico en minimale belasting voor een groot deel van het niet-therapeutisch onderzoek kunnen komen te vervallen. Uitgangspunt blijft wel dat de balans tussen het belang van het onderzoek en de risico?s en belasting voor het kind positief moet zijn. Hierbij moeten ook ernst en stadium van de aandoening en het beloop hiervan worden meegewogen. Het wachten is nu op aanpassing van de Wet medisch-wetenschappelijk onderzoek met mensen (WMO) die nog uitgaat van het uitgangspunt ?nee, tenzij?.
Human remains can be discovered in freshwater or marine ecosystems, circumstances where insects and other invertebrates have infrequently been used for understanding the time of postmortem submersion. In this study, the identification and succession of epinecrotic bacterial communities on vertebrate remains were described during decomposition in a temperate headwater stream during two seasons (summer and winter). Bacterial communities were characterized with 454 pyrosequencing and analyzed at phyletic and generic taxonomic resolutions. There was a significant increase in genera richness over decomposition during both seasons. Additionally, multivariate statistical modeling revealed significant differences in bacterial communities between seasons at both taxonomic resolutions and siginificant genera differences among sampling days within each season, suggesting a succession of these communities. These data are the first to describe aquatic bacterial succession using high-throughput metagenomic sequencing on vertebrate remains submerged in a freshwater habitat, and provide initial evidence for their potential use in forensic investigations. © 2015 American Academy of Forensic Sciences.
The study of decomposition by using accumulated degree days (ADDs) has been suggested not only in terrestrial decay but also for water-related deaths. Previous studies have demonstrated that the accumulation of thermal energy as a function of the post-mortem submersion interval (PMSI) can be derived from a descriptive decompositional scoring system (DSS). In order to verify how useful can the total aquatic decomposition score (TADS) for ADD prediction be, a comparative taphonomic study has been performed between two series of bodies: 16 corpses found floating in shallower waters with a presumptive PMSI from 3 to 118 days and exposed to water temperatures (Tw) between 10.5 and 20.3 °C approximately equating from a minimum of 46 to 1.392 ADD; 52 bodies, all victims of a single shipwreck, found in sequestered environments and subjected to constant Tw of 4 °C for 210 days approximately equating to 840 ADD. The two series of bodies have revealed different stages of decay and a large DSS variability. In most of bodies, freshly formed adipocere was able to delay the appearance of later decompositional stages explaining why most of the bodies were in relatively good condition. Although promising, the accuracy of the TADS model can be affected by adipocere and animal activity. The TADS model suffers of the same limitations for ADD calculations as they can give a false perception of accuracy due to the complexity of integrating all changing factors affecting human decay in sequestered and non-sequestered marine environments (currents, animal activity, water temperatures, depth of submersion).