A laboratory study of the pollution of formaldehyde in cemeteries (South Africa)

Abstract

Cemeteries are known to be associated with soil and groundwater pollution from contaminants in coffin materials. However, possible contamination from embalming fluids such as formaldehyde has not been investigated. Formaldehyde is a recognised carcinogen, which is primarily toxic after inhalation, skin contact or ingestion. Although it is maintained that formaldehyde breaks down into innocuous compounds, this has not been established at sites such as cemeteries where there is a continuous addition of formaldehyde-preserved bodies, sometimes on a daily basis. It is also not confirmed whether different soil types and environmental conditions affect the leaching of formaldehyde into groundwater resources. This study comprises a laboratory study of the leaching potential of formaldehyde through different soils and environmental conditions. Twenty-seven containers with taps were filled with either sandy, silty or clayey soils. Samples of burial materials and a cloth saturated with formalin were buried within each column. These were exposed to conditions simulating that of the environment, i.e. (1) different temperatures, (2) heavy or prolonged rainfall and (3) using either acidic or slightly acid water. Leachate samples were collected every 2 weeks for a period of 24 weeks and analysed for formaldehyde using acid titration. The results showed that most formaldehyde percolated through the soil between week 6 and week 14 of interment, with a greater amount being leached from sand. Neither temperature nor pH affected the amount of formaldehyde leached; however, conditions simulating heavy rainfall facilitated leaching. Although a total of only 3% of the initial amount of formaldehyde mobilised, concentrations of up to 15 mg/L formaldehyde were recorded on two occasions, exceeding the tolerable concentration recommended by the World Health Organisation.

Full text

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
A laboratory study of the pollution of formaldehyde in cemeteries
1
(South Africa)
2
Sunette van Allemann1, Jana Olivier1, Matthys A. Dippenaar2a
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4
1 Department of Geography, Geoinformatics and Meteorology, University of Pretoria, South Africa
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2 Engineering Geology and Hydrogeology, Department of Geology, University of Pretoria, South
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Africa
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a Corresponding author (matthys.dippenaar@up.ac.za / madippenaar@gmail.com)
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9
Abstract
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11
Cemeteries are known to be associated with soil and groundwater pollution from contaminants in
12
coffin materials. However, possible contamination from embalming fluids such as formaldehyde has
13
not been investigated. Formaldehyde is a recognised carcinogen, which is primarily toxic after
14
inhalation, skin contact or ingestion. Although it is maintained that formaldehyde breaks down into
15
innocuous compounds, this has not been established at sites such as cemeteries where there is a
16
continuous addition of formaldehyde-preserved bodies, sometimes on a daily basis. It is also not
17
confirmed whether different soil types and environmental conditions affect the leaching of
18
formaldehyde into groundwater resources. This study comprises a laboratory study of the leaching
19
potential of formaldehyde through different soils and environmental conditions. Twenty-seven
20
containers with taps were filled with either sandy, silty or clayey soils. Samples of burial materials
21
and a cloth saturated with formalin were buried within each column. These were exposed to
22
conditions simulating that of the environment i.e. (i) different temperatures, (ii) heavy or prolonged
23
rainfall, and (iii) using either acidic or slightly acid water. Leachate samples were collected every two
24
weeks for a period of 24 weeks and analysed for formaldehyde using acid titration. The results
25
showed that most formaldehyde percolated through the soil between week six and week 14 of
26
interment, with a greater amount being leached from sand. Neither temperature nor pH affected the
27
amount of formaldehyde leached; however, conditions simulating heavy rainfall facilitated leaching.
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Although a total of only 3% of the initial amount of formaldehyde mobilised, concentrations of up to
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15mg/L formaldehyde were recorded on two occasions, exceeding the Tolerable Concentration
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recommended by the World Health Organization.
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32
Keywords: Cemeteries; Interment; Formaldehyde; Burial Materials; Embalming; Formalin.
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1. Introduction
35

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
1
The main sources of pollution from cemeteries are (a) human bodies; (b) embalming fluids, which
2
primarily contain formaldehyde (Guttman et al. 2012); and (c) the fabrication materials of coffins,
3
which may contain harmful and toxic metals that could seep into the soil (Jonker and Olivier 2012).
4
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The pollution potential of cemeteries has received increasing attention over the past few years. This
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research has dealt with the environmental and health hazards associated with metals used in coffin
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materials and microorganisms from decomposing corpses, which may potentially become mobile,
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seep into the soils and end up in nearby water reserves. However, the potential pollution due to
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embalming fluids, such as formaldehyde (Guttman et al. 2012), has gone unnoticed.
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Although not required by law, embalming is performed for the benefit of loved ones to ensure that
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family members are not left with an undesirable last memory (Frater 2007). Formaldehyde is
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currently the main embalming fluid used in South Africa, athough it is not known whether
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formaldehyde actually leaches into the soil and groundwater. Different soil types, pH, rainfall
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intensities and temperature may also influence the leaching and decomposition rates of formaldehyde
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and, since it is difficult to determine these relationships directly in the field, a laboratory study under
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controlled conditions was conducted.
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The aim of this laboratory study is to determine whether formaldehyde from burial materials has the
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potential to contaminate groundwater. The objectives are to (a) determine whether the formaldehyde
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becomes mobile and leaches into groundwater and, if so, to (b) estimate the rate of leaching and (c)
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assess whether the amount of rainfall and its pH, the type of soil and temperature play a role in the
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rate of leaching.
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2. Literature
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Despite the widely held belief that the decomposition of bodies and the stench of decomposing
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corpses were potential health hazards to living individuals, it was only in the mid-1800s when
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Dr George Walker (a British surgeon) described how the soil around graves became saturated with
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potentially deadly decomposing matter (Tarlow 2000). In 1845, Snow established a clear link between
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water and cholera within close proximity of graveyards (Eyler 2001). Subsequent to this research,
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numerous researchers have shown that water bodies and wells near cemeteries could become
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contaminated with bacteria from decaying bodies, and therefore result in environmental and health
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hazards (e.g. Dent 2000; Dippenaar 2014; Engelbrecht 1998; Eyler 2001; Fogli 2016; Tumagole 2009;
35
Zychowski 2012).
36

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
1
Although the first studies focused on the contaminants associated with bodies and associated bacteria,
2
recent studies have been conducted to inclide contamination from minerals and metals contained in
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burial materials such as coffins and caskets. Van Haaren (1951) and Dent (1998) found above normal
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concentrations of salts in the vicinity of graves in the Netherlands and Australia respectively. High
5
levels of metals and trace minerals were also recorded in cemeteries in many countries ranging from
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Brazil, Iran, Rwanda, Australia, China and South Africa (Amuno 2013; Amuno and Oluwajana 2014;
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Barros et al. 2008; Dent and Knight 1995; Jonker and Olivier 2012; Pour and Khezri 2010; Spongberg
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& Becks 2000)
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10
In comparison to research on decomposing bodies and burial materials, possible contamination from
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embalming agents has received relatively little attention. According to Ezugworie et al. (2008),
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Ancient Egypt is principally associated with the beginnings of the art and techniques of embalming.
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These embalming agents comprised mainly of mixtures of resins, herbs, spices, honey and minerals
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and may have been innocuous (Mdladenov 2016). It is believed, for instance, that the body of
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Alexander of Macedonia was transported from Babylon to Macedonia in a coffin filled with honey.
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Since the advent of the American Civil War (1861) until about 1910, the main ingredient for
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embalming fluids was essentially arsenic (Konefes and McGee 2001). Even though arsenic is very
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effective, it is not only toxic, but also persistent and will never be able to degrade into harmless by-
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products (Singh et al. 2011). The use of arsenic was a significant improvement from refrigeration or
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dry ice (carbon dioxide) when preserving the deceased for burial or transport, but embalming
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practitioners did not take into consideration the long-term effects of these substances (Konefes and
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McGee 2001). As a result, large concentrations of arsenic were placed within burial grounds and
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ultimately local water supplies.
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Today it is known that arsenic poses a significant environmental threat and health hazard since some
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of the arsenic in an embalmed body can leach out and eventually contaminate nearby groundwater
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(Konefes and McGee 2001). In a hypothetical case study, Konefes and McGee (2001) estimated that,
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in a modest-sized town recording 2,000 deaths between 1880 and 1910, and if only half of the
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deceased were embalmed with 30 ml of pure arsenic, the cemetery would contain 172 kg of arsenic. If
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the embalmers used more arsenic, such as 1.5 litres per person (depending on the formula used), the
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cemetery would contain over one ton of arsenic. Both of these scenarios would cause a significant
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amount of contamination at one location.
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35

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
Although arsenic was the main ingredient of embalming fluids, other embalming compositions used
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less frequently also consisted of similar toxins such as mercury and creosote (Johnson 1995).
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Nowadays embalming fluids contain formaldehyde, distilled water, phenol and glycerol (Anat 1993),
3
of which 10 litres of the mixture (containing 1.5 litres of formaldehyde) (Karmaka 2010) is required
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for a 70 kg body. Formaldehyde (CH2O) is released during decomposition and has been shown to be
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carcinogenic (especially leukaemia) to living organisms (Guttman et al. 2012). According to a 2002
6
report, the World Health Organization (2002) indicated that when formaldehyde comes into contact
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with water it breaks down into methanol, amino acids and several other chemicals and therefore does
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not persist in the environment. However, its persistence in a cemetery environment has not been
9
assessed, especially given the role of the vadose (unsaturated) zone and the time for it to break down
10
into harmless byproducts.
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3. Materials and Methods
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Given the difficulty in determining the rate of formaldehyde leaching in situ, a laboratory simulation
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under controlled conditions was designed. This simulation of formaldehyde at different environmental
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conditions including variation in (i) the type of soil, (ii) rainfall intensity, (iii) pH and (iv) temperature
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was carried out over a period of 24 weeks. These experiments were conducted at Orytech (Pty) Ltd,
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an independent paint/coating, corrosion, environmental and materials testing facility located in
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Johannesburg, Gauteng (as elaborated by Van Allemann 2017).
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Sand, silt and clay were collected from Klerksdorp, located in North-West Province (South Africa).
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The soil types were determined by means of particle size distribution where sand particles are 0.5-2.0
23
mm, silt 0.002-0.05 mm and clay less than 0.002 mm (Brady and Weil 2008). The possible presence
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of some organic materials in the samples are duly noted.
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The soil samples were placed into plastic columns with a diameter of 170 mm and a height of 190
27
mm. The soil samples were slightly compacted to minimize pore spaces between the soil particles.
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The plastic containers were fitted with a small tap at the bottom of each container to allow water
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leachate to move out of the column, and a material sieve to prevent blockage.
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Embalming fluid and coffin materials were collected from one of South Africa’s oldest and largest
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funeral suppliers. Until recently, coffin materials, such as handles and ornaments, were made of
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metals such as aluminium, copper, mild steel, zinc and its alloys, as well as silver and bronze. This
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has now been replaced with plastic handles and ornaments. The material safety data sheets of these
35
indicated that the plastic comprise of polypropylene and contain traces of formaldehyde (Motlatsi
36

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
2007). The varnish also contain traces of formaldehyde (Chemical Specialists (Pty) Ltd 2009) and the
1
collected embalming fluid, formalin, consists of 10% formaldehyde.
2
3
Information obtained from the South African Weather Service (SAWS 2016) was used to identify
4
general climatic conditions occurring over South Africa. From this it became evident that the average
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daily temperature ranges between 20°C and 30°C and rainfall, especially in the summer rainfall
6
regions of the country, frequently occur in the form of heavy thunderstorms. Conversely, rainfall is
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less intense and often prolonged in the winter rainfall region. In rural, pollution-free areas, the
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rainwater usually has a pH of 5.6, but when combined with emissions containing sulphur dioxide or
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nitrogen oxide, the rain becomes more acidic than usual with typical acid rain having a pH of 4
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(Hairston 2003).
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This information was used to simulate natural environmental conditions in the laboratory study.
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A sample of each coffin material, as well as a pure cotton cloth of 50 x 50 mm which had been dipped
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in 15.6 ml formalin, a 4% formaldehyde solution, was ‘buried’ at a depth of 95 mm of the soil column
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(Figure 1). The soil columns were given a unique sample identification and labelled accordingly. Half
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of the containers were then placed within a 30oC chamber and the other half in a temperature
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controlled room, which was set at 20oC.
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20
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Figure 1. Setup of the laboratory experiment.
22
23

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
In addition to simulating moderate and hot temperatures, the samples were watered with 1L of water
1
every two weeks to simulate different rainfall intensities. The samples exposed to ‘prolonged rainfall’
2
periods received 1L of water over a period of 4 days every second week whereas the entire 1 L of
3
water was added to the containers every second week to simulate heavy rainfall (referred to as ‘flash
4
floods).
5
6
The water added to the samples, which simulated the different rainfall intensities, also had different
7
pH values. Half of the samples were given water with a pH of 6 (slightly acidic) and the other half
8
water with a pH of 4 (acidic). In order to achieve these pH values, hydrochloric acid (HCl) was added
9
to distilled water in order to increase the acidity. Figure 2 illustrates the various conditions under
10
which the samples were tested. Interment continued for a period of 6 months (24 weeks).
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12
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Figure 2. Variables tested during the experimental study.
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Table 1 summarises the simulated conditions to which the sources of formaldehyde were exposed.
16
17

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
Table 1. A summary of the controlled variables of the laboratory simulation of formaldehyde over a
1
period of 24 weeks.
2
Variables
Description of each controlled variable
Soil Type
Sand
Added and compacted into 170 mm x 190 mm soil columns
Silt
Added and compacted into 170 mm x 190 mm soil columns
Clay
Added and compacted into 170 mm x 190 mm soil columns
‘Rainfall’ Intensity
Flash Flooding
1L of distilled water once-off every second week
Prolonged
1L of distilled water over a period of 4 days every second week
Temperature
Moderate
20oC continuously
Warm
30oC continuously
‘Rainfall’ pH
Acidic
pH 4 continuously
Slightly Acidic
pH 6 continuously
Control Samples
Different soil types with no formaldehyde, which were exposed to neutral
flash floods at room temperature
3
It is important to note that formaldehyde also arises from the oxidation of natural organic material
4
(World Health Organization 2005), which suggests that formaldehyde is a natural occurring substance
5
in small concentrations. For this reason, soil columns compacted with the different soil types without
6
any formaldehyde were kept as controls, which are also exposed to neutral flash floods at room
7
temperature. Thus, there were 27 samples in total, which allowed for differentiation between the three
8
different soil types, simulated rainfall intensities (flash floods or prolonged rainfall periods),
9
temperature (20oC or 30oC) and slightly acidic or acidic ‘rain’.
10
11
The water leached out of each sample was collected fortnightly and given a unique sample
12
identification number. The concentration of formaldehyde in each sample was determined (in
13
triplicate) by means of a Hanna formaldehyde test kit. The test involved simple acid titration where
14
formaldehyde reacts with sodium sulphite (Na2SO3) to form an alkaline solution, which is then titrated
15
with HCl to form a yellow solution (Hanna Instruments n.d.). The amount of HCl titrated is
16
proportional to the concentration of formaldehyde in the solution. After analysis, the results were
17
tabulated and the formaldehyde concentrations were divided into equal pentad values, which are
18
indicative of the relative concentration of formaldehyde for a given sample. Excel (Microsoft 2010)
19
was used for calculations and rafting figures.
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21
Experimental studies such as this have certain limitations. Natural environments may be more prone
22
to bioaccumulate metals or digest formaldehyde than the biologically inert soils used in the study.
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Furthermore, this experimental study do not account for all possible influences of other parameters
24
such as ultraviolet radiation or light, variable temperatures, variable redox conditions and so forth.
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26
4. Results and Discussion
27

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
1
The amount of formaldehyde collected from each of the containers is given in Table 2.
2
3
Table 2. Formaldehyde (mg/l) concentrations of tested water samples over a period of 24 weeks (W2 – week 2;
4
etc.).
5
Legend (mg/l)
0.00 to 3.00
3.10 to 6.00
6.10 to 9.00
9.10 to 12.00
12.10 to 15.00
6
4.1. General trends in formaldehyde leaching
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8
Sample Identification
Fortnightly Concentrations in mg/l
W 2
W 4
W 6
W 8
W 10
W 12
W 14
W
16
W
18
W
20
W
22
W
24
Sum
(mg)
A coffin sand slightly acidic
20 prolong
1.50
0.50
5.00
4.00
3.00
2.00
0.50
0.20
0.10
0.10
0.10
0.10
17.10
B coffin sand slightly acidic
30 prolong
0.50
0.40
5.00
4.00
4.00
1.00
0.40
0.40
0.20
0.20
0.10
0.15
16.35
C coffin sand acidic 20
prolong
2.00
0.40
2.50
15.00
0.40
0.10
0.20
0.10
0.10
0.10
0.15
0.20
21.25
D coffin sand acidic 30
prolong
1.00
0.50
1.00
4.00
9.00
0.20
0.10
0.10
0.10
0.10
0.15
0.10
16.35
E coffin sand slightly acidic
20 flash
1.50
0.40
7.00
5.00
2.00
0.40
0.10
0.20
0.20
0.20
0.10
0.15
17.25
F coffin sand slightly acidic
30 flash
1.50
0.60
8.00
7.00
0.40
0.20
0.00
0.20
0.10
0.15
0.20
0.10
18.45
G coffin sand acidic 20 flash
1.50
0.50
10.00
2.00
0.40
0.40
0.20
0.40
0.20
0.10
0.15
0.10
15.95
H coffin sand acidic 30 flash
0.50
0.80
5.00
6.00
4.00
0.25
0.10
0.30
0.10
0.10
0.15
0.20
17.50
I sand control
0.10
0.10
0.20
0.10
0.10
0.10
0.20
0.10
0.10
0.10
0.10
0.10
1.40
Total Sand (Ʃ) excluding
control
10.00
4.10
43.50
47.00
23.20
4.55
1.60
1.90
1.10
1.05
1.10
1.10
140.20
J coffin silt slightly acidic 20
prolong
1.50
0.40
5.00
2.50
4.00
1.00
3.00
0.20
0.10
0.20
0.10
0.15
18.15
K coffin silt slightly acidic 30
prolong
1.00
0.40
5.00
2.00
3.00
2.00
0.20
0.10
0.20
0.10
0.10
0.10
14.20
L coffin silt acidic 20 prolong
0.50
0.40
0.20
4.00
5.00
3.00
0.40
0.10
0.20
0.15
0.10
0.15
14.20
M coffin silt acidic 30
prolong
2.00
0.40
4.00
3.00
4.00
1.00
0.30
0.20
0.40
0.20
0.10
0.10
15.70
N coffin silt slightly acidic 20
flash
1.00
0.40
4.00
4.00
5.00
0.40
0.20
0.20
0.20
0.20
0.10
0.15
15.85
O coffin silt slightly acidic 30
flash
1.50
0.40
2.50
3.00
5.00
3.00
0.50
0.30
0.40
0.15
0.15
0.10
17.00
P coffin silt acidic 20 flash
1.00
1.00
8.00
2.00
0.40
1.00
1.00
0.40
0.10
0.10
0.10
0.10
15.20
Q coffin silt acidic 30 flash
1.50
0.40
12.00
3.00
0.40
0.20
0.10
0.10
0.20
0.10
0.15
0.20
18.35
R silt control
0.20
0.10
0.20
0.10
0.20
0.20
0.20
0.20
0.10
0.10
0.20
0.20
2.00
Total Silt (Ʃ) excluding
control
10.00
3.80
40.70
23.50
26.80
11.60
5.70
1.60
1.80
1.20
0.90
1.05
128.65
S coffin clay slightly acidic
20 prolong
1.50
0.40
8.00
1.00
1.00
0.20
0.40
0.20
0.30
0.10
0.20
0.15
13.45
T coffin clay slightly acidic
30 prolong
1.50
0.40
8.00
2.00
0.50
0.40
0.20
0.10
0.50
0.10
0.20
0.10
14.00
U coffin clay acidic 20
prolong
1.00
0.40
0.20
1.00
5.00
3.00
4.00
0.50
0.20
0.10
0.10
0.20
15.70
V coffin clay acidic 30
prolong
0.50
0.60
5.00
3.00
2.00
1.00
3.00
0.80
0.10
0.20
0.10
0.15
16.45
W coffin clay slightly acidic
20 flash
1.00
0.40
1.00
14.00
0.10
0.40
0.10
0.10
0.20
0.10
0.20
0.15
17.75
X coffin clay slightly acidic
30 flash
1.00
0.50
2.00
15.00
0.10
0.10
0.20
0.20
0.10
0.20
0.10
0.10
19.60
Y coffin clay acidic 20 flash
1.00
0.60
4.00
1.00
5.00
0.50
3.00
0.20
0.20
0.10
0.20
0.10
15.90
Z coffin clay acidic 30 flash
1.00
0.40
0.50
1.00
10.00
2.00
0.20
0.40
0.20
0.15
0.20
0.20
16.25
AZ clay control
0.10
0.20
0.10
0.10
0.00
0.10
0.10
0.20
0.00
0.10
0.10
0.10
1.20
Total Clay (Ʃ) excluding
control
8.50
3.70
28.70
38.00
23.70
7.60
11.10
2.50
1.80
1.05
1.30
1.15
129.10

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
Comparison of the total amount of formaldehyde leached over the 24-week period from sand, silt and
1
clay (Table 2) indicated that a total of 140.2 mg/l was leached from sand, 128.65 mg/l from the silt
2
columns and 129.1 mg/l from the clay. This suggests that some of the formaldehyde were attached to
3
soil particles and could possibly flush out of silt and clay at a later stage. However, the soils
4
themselves were sources of formaldehyde (as shown by the controls). If this portion of the
5
formaldehyde is excluded from each of the samples, a total of 138.8 (i.e. 140.20-1.40), 126.65 and
6
127.9 mg/l were leached from sand, silt and clay, respectively. Sand appears to leach formaldehyde at
7
a greater rate. However, use of Student’s t-test revealed that there is no significant difference in the
8
amounts leached from the different soils, since the p-value is 0.316 between sand and silt. This is not
9
significant at p > 0.05.
10
11
Table 2 also indicates that most of the soils only started to percolate formaldehyde out of the system
12
at week six, and most of the formaldehyde appeared to have leached out of the soil by week 16.
13
Further scrutiny (Figure 3) shows that sand flushed formaldehyde out faster than silt and clay. By
14
weeks 12 and 14, the amount of formaldehyde leached from the burial materials in sandy soils had
15
decreased markedly whereas such low amounts were only reached in week 16 in silty and clayey
16
soils. This may, in part, be ascribed to the high permeability well-drained nature of sand compared to
17
silt and clay, implying that formaldehyde may be retained longer in finer-grained soils.
18
19
20
Figure 3. Cumulative plot of formaldehyde leached out of different soil types over the 24-week period.
21
22
4.2. The effect of changing environmental conditions
23
24
The effects of differences in the amount of formaldehyde leached from sand, silt and clay with
25
changes in temperature, rainfall intensity and pH are summarised in Table 3. These values were
26

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
obtained by summing the appropriate values in Table 2 (for example, formaldehyde leached from
1
sand at 20 ͦ C was 17.1+21.25+17.25 + 15.95 = 71.55 mg/l).
2
3
Table 3. Total amount of formaldehyde leached from soils over a 24-week period (mg/L).
4
Type of Soil
Temperature (°C)
Rainfall Intensity
Rainfall pH
20
30
Prolonged
Flash floods
Slightly Acidic
Acid
Sand
71.55
68.65
71.05
69.15
69.15
71.05
Silt
63.40
65.25
62.25
66.40
65.20
63.45
Clay
62.8
66.25
59.60
69.50
64.80
64.30
Total
197.75
200.15
192.90
205.05
199.15
198.80
Mean (n = 12)
16.48
16.68
16.08
17.08
16.60
16.57
5
4.2.1. Temperature
6
7
Table 3 clearly shows that, in sand, higher temperatures inhibited formaldehyde from percolating out
8
of the system. However, the opposite seems to be true for clay and silt, showing increased amounts of
9
formaldehyde leaching out of the system at increased temperatures. Comparison of Figures 4a-c
10
shows that, during higher temperatures, silt released the formaldehyde more uniformly than sand and
11
clay. In general, the temporal pattern of formaldehyde percolated from the soils were essentially the
12
same at 20°C and 30°C.
13
14

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
1
Figure 4. (a) The amount of formaldehyde leached from sand at different temperatures. (b) The amount
2
of formaldehyde leached from silt at different temperatures. (c) The amount of formaldehyde leached from clay
3
at different temperatures.
4
5

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
Observation of the soil columns indicated that sand were much drier than silt and clay at 30oC (as is
1
expected by the low moisture retention and high permeability compared to silt and clay), which could
2
explain this variation. Silt and clay subsequently stayed moist for longer, allowing them to flush out
3
greater amounts of formaldehyde at higher temperatures. Once again, the Student’s t-test indicated
4
that there is no significant difference in the amounts leached from sand at different temperatures,
5
since the p-value is 0.294, which is not significant at p > 0.05. Since the effect of temperature
6
difference is less in silt and clay, these can also be assumed to be statistically not significant at p >
7
0.05.
8
9
4.2.2. Rainfall intensity
10
11
More formaldehyde was leached from sandy soils during prolonged rainfall, whereas the opposite is
12
true for silt and clay (Table 3). Comparison of Figures 5a-c show that generally, prolonged rainfall
13
periods appeared to have flushed out formaldehyde faster than flash floods in sandy soils (week 12)
14
while silt and clay soils only released most of the formaldehyde by week 16. However, silt and clay
15
showed several instances of high formaldehyde flushing during ‘flash floods’ during the first 10
16
weeks. The Student’s t-test confirmed that there is a significant difference in the amounts leached
17
from clay at different rainfall intensities, since the p-value is 0.033 (p < 0.05). The opposite is true for
18
sand and silt, with p-values of 0.362 and 0.203, respectively.
19
20

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
1
Figure 5. (a) The amount of formaldehyde leached from sand at different rainfall intensities. (b) The
2
amount of formaldehyde leached from silt at different rainfall intensities. (c) The amount of formaldehyde
3
leached from clay at different rainfall intensities.
4
5
4.2.3. Rainfall pH
6
7

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
Table 3 indicates that the acidity of the water did not seem to have a significant effect on the rate of
1
leaching. Initially, more formaldehyde was flushed out of sand and clay soils under less acidic rainfall
2
conditions. Thereafter, the more acidic rainwater flushed out the remaining formaldehyde. With the
3
exception of week 6, the same pattern seems to hold for silty soils (Figures 6a-c). Yet, application of
4
Student’s t-test revealed that there is no significant difference in the amounts leached from clay with
5
rainfalls at different pH values, since the p-value is 0.468 (p > 0.05).
6
7

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
1
Figure 6. (a) The amount of formaldehyde leached from sand at different pH values. (b) The amount of
2
formaldehyde leached from silt at different pH values. (c) The amount of formaldehyde leached from clay at
3
different pH values.
4
5
4.3. Total amount of formaldehyde leached from soils
6

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
1
Calculations showed that the 15.6 ml formalin (containing 4% formaldehyde and with a density
2
approx. 1 g/ml) solution interred in the columns contained approximately 624 mg formaldehyde. Of
3
this an average of 16.38 mg and a maximum of 21.25 mg leached from the samples (Table 2). As
4
mentioned before, formaldehyde also arises from the oxidation of natural organic material, which
5
explains why small concentrations of formaldehyde persist for a long period of time in the soil
6
samples, including the control samples (Table 2). However, this naturally occurring formaldehyde in
7
not included in the calculations.
8
9
Ostensibly the embalming fluid does not appear to pose a risk to the environment since only
10
approximately 2.6% formalin buried in the soil percolates out over a 6-month period. However, in a
11
cemetery, burials take place at regular intervals, often daily. In the case of the Zandfontein Cemetery
12
in Tshwane (Pretoria, South Africa), for example, 60 000 burials have taken place over a period of 60
13
years (Jonker and Olivier 2012), equating to almost 20 burials per week. Since a 1.5 L formalin
14
solution is used to embalm a 70 Kg body, it is thus reasonable to assume that high concentrations of
15
formaldehyde could leach from cemetery soils on a daily basis.
16
17
Whether these concentrations make their way through water systems and into water sources are still
18
unknown and would depend on the environmental and other conditions. Noteworthy is the fact that, in
19
this laboratory study, the formaldehyde leachate in the experiment reached concentrations of up to 15
20
mg/L on two occasions, that is six times higher than the established a tolerable concentration of 2.6
21
mg/L for ingested formaldehyde (World Health Organisation 2002, 2005).
22
23
5. Conclusions
24
25
The contamination of soil and groundwater by embalming fluids is a key element that has largely
26
been overlooked in research involving cemeteries. This study comprises of a laboratory study in
27
which environmental conditions prevailing in South Africa are emulated to determine the amount and
28
rate of leaching of formaldehyde through different types of soils.
29
30
Contrary to expectation, formaldehyde persists in soils and slowly percolates through the soil for
31
periods of at least 14 weeks. Different environmental conditions such as soil type, high and low
32
temperatures, rainfall and pH of rainfall do not appear to affect the amount of leachate or the mobility
33
rate through soils, although sand allows more effective leaching.
34
35

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
A total of around 2.6% of the formalin introduced into the experimental soil columns leached from the
1
soil over a six-month period. The remaining >97% can safely be assumed to either break down, or to
2
only mobilise out of the soil column at a later stage. Despite the small amount of formalin found in
3
the leachates, concentrations exceeding the tolerable concentration of the compound, as given by the
4
World Health Organisation, leached from all the experimental soil columns at some stages between
5
weeks 6 to 14.
6
7
Considering the fact that burials take place on a weekly basis in operational cemeteries in South
8
Africa, the accumulated amount of formaldehyde reaching the groundwater may be a matter of
9
concern. It is recommended that surface and groundwater sources in the immediate vicinity be
10
monitored on a regular basis, and it is also recommended that drinking water standards for formalin be
11
introduced.
12
13
6. Acknowledgements
14
15
The authors wish to acknowledge the Water Research Commission of South Africa (www.wrc.org.za)
16
for the funding of project K5/2449 and Orytech (Pty) Ltd for the use of their facilities. Additional
17
acknowledgement is extended to all parties involved in the project for their valuable input throughout
18
discussions and reviews.
19
20
Further thanks are extended to the journal, its editor and reviewers for valuable input.
21
22
The authors declare no conflict of interest.
23
24
7. References
25
26
Amuno SA (2013) Potential ecological risk of heavy metal distribution in cemetery soils. Water, Air and Soil
27
Pollution Journal 224:1435-1447.
28
Amuno SA, Oluwajana, A (2014) Comparative assessment of trace metals in soils associated with casket
29
burials: Towards implementing green burials. Eurasian Journal of Soil Science 3:65-76.
30
Anat, J (1993) An improved composition for embalming fluid to preserve cadavers for anatomy 182:295-297.
31
Barros YJ, Melo VD, Zanello S, Romano EN, Luciano PR (2008) Heavy metal contents and mineralogical
32
characteristics of soils from the Santa Candida Municipal Cemetery in Curitiba. Revista Brasileira De
33
Ciencia Do Solo 32(4):1763-1773.
34
Brady NC, Weil RR (2008) The Nature and Properties of Soils. New Jersey: Pearson Education Inc.
35
Chemical Specialists (Pty) Ltd (2009) Material Safety Data Sheet 8270-203: Woodline Clear Sealer, Durban,
36
South Africa: ChemSpec.
37

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
Dent BB (2000) Decay products in cemetery ground waters. Rio de Janeiro, 31st International Geological
1
Congress 6-17.
2
Dippenaar, M. A. (2014). Towards a multi-faceted Vadose Zone Assessment Protocol: cemetery guidelines and
3
application to a burial site located near a seasonal wetland (Pretoria, South Africa). Bull Eng Geol Environ.
4
73(4):1105-1115.
5
Dent BB, Knight, MJ (1995) A watery grave: The role of hydrogeology in cemetery practice. Am. Coll. Couns.
6
Assoc. 2:19-22.
7
eNCA, 2015. South African Water Crisis. [Online] Available at: https://www.enca.com/south-africa/sa-water-
8
crisis-map-what-you-need-know
9
Engelbrecht JF (1998) Groundwater pollution from cemeteries: A case study. Porto, Portugal, 1-8.
10
Eyler JM (2001) The changing assessments of John Snow’s and William Farr’s cholera studies. History of
11
epidemiology 46(1):225–232.
12
Ezugworie J, Anibeze C, Ozoemena F (2008) Trends in the development of embalming methods. The Internet
13
Journal of Alternative Medicine 7:2.
14
Fogli, D (2016) Techniques of decomposition of bodies adopted in cemeteries and their relations with the
15
environment. [Online] Available at: http://docstoc.com.docs.5177995/decomposition-dead-bodies
16
Frater L (2015) The 5 Stages of Embalming. [Online] Available at: http://listverse.com/2007/11/08/the-5-stages-
17
of-embalming/
18
Fraust DG (2008) This Republic of Suffering: Death and the American Civil War. New York: Alfred A. Knopf.
19
Gagnon, A, 2015. Death and Mourning in the Civil War Era. [Online] Available at:
20
http://connecticuthistory.org/death-and-mourning-in-the-civil-war-era/
21
Guttman S, Watson J, Miller V (2012). Till Death Do We Pollute, and Beyond, Canada: Trent University.
22
Hairston, JE, 2003. Acid Rain: An Overview, Alabama: Alabama Cooperative Extension System.
23
Hanna Instruments (n.d.) Instruction Manual for HI 3838 Formaldehyde Test Kit, Hanna Instruments.
24
IPCS (2002) World Health Organization (Concise International Chemical Assessment Document No. 40),
25
Geneva, Switzerland: World Health Organization.
26
Johnson EC (1995) A History of the Art and Science of Embalming. Casket and Sunnyside.
27
Jonker C, Olivier J (2012) Mineral contamination from cemetery soils: Case study of Zandfontein cemetery,
28
South Africa. International Journal of Environmental Research and Public health ISSN 1660-4601, 511-
29
520.
30
Karmakar RN (2010) Forensic Medicine and Toxicology. 3rd ed. India: Academic Publishers.
31
Konefes JL, McGee MK (2001) Old Cemeteries, Arsenic, and Health Safety. In: Dangerous Places: Health,
32
Safety and Archaeology. Westport, United States: Greenwood Publishing Group Inc. 129-134.
33
Mdladenov S (2016) The preservative effect of honey. [Online] Available at: http://honeypedia.info/the-
34
preservative-effect-of-honey
35
Moore B, Lundell M (2012) Mound Builders of the Ancient World, Phoenix: Pueblo Grande Museu.
36
Motlatsi MS (2007) Material Safety Data Sheet: Polypropylene, Sandton, South Africa: Sasol.
37
Niven J (1965) Connecticut for the Union the Role of the State in the Civil War. New Haven, CT: Yale
38
University Press.
39

This is a pre-print of an article already published. The final authenticated version is available online at: Van Allemann ST,
Olivier J, Dippenaar MA. (2018). A laboratory study of the pollution of formaldehyde in cemeteries (South Africa).
Environmental Earth Science. https://doi.org/10.1007/s12665-017-7219-z
Pacheco A et al., (1991) Cemeteries - A potential risk to groundwater. Water Science and Technology 24(11):
1
97-104.
2
Perkins S (2014) Mummifying-balm recipe is older than the pharoahs. [Online] Available at:
3
http://www.nature.com/news/mummifying-balm-recipe-is-older-than-the-pharaohs-1.15717
4
Phillips N (2015) New species of extinct human 'Homo naledi' found in South African cave. [Online] Available
5
at: http://www.smh.com.au/technology/sci-tech/new-species-of-extinct-human-homo-naledi-found-in-
6
south-african-cave-20150910-gjjypf.html
7
Pour SK, Khezri SM (2010) Assessing the groundwater resources pollution potential by Beheshte Zahra
8
Cemetery. International Conference on Chemistry and Chemical Engineering (ICCCE) 414-418.
9
Rodriques L, Pacheco A (2003) Groundwater contamination from cemeteries cases of study. Porto.
10
South African Weather Service (SAWS) (2016) Climate. [Online] Available at:
11
http://www.weathersa.co.za/climate/recent-climate
12
Spongberg A, Becks P (2000) Inorganic soil contamination from cemetery leachate. Water, Air and Soil
13
Pollution 117:313-327.
14
Tarlow S (2000) Landscapes of memory; the nineteenth-century garden cemetery. European Journal of
15
Archaeology 3(2):217-239.
16
Trochu AF (2015) About Incorruptibles - The Catholic Heart. [Online] Available at:
17
www.thecatholicheart.org/pdf/AboutIncorruptibles.pdf
18
Tumagole KB (2009) Geochemical survey of underground water pollution at Ditengteng Northern Cemetery
19
within the Tshwane municipality, Johannesburg: University of Johannesburg.
20
van Allemann ST (2017) A laboratory simulation of the potential groundwater contamination associated with
21
burial materials. MSc dissertation (unpublished). University of Pretoria, Pretoria, South Africa.
22
van Haaren FW (1951) Cemeteries as sources of groundwater contamination (emneerlandes). Water 35(16):167-
23
172.
24
World Health Organization (2002) Formaldehyde: Concise International Chemical Assessment Document 40,
25
Geneva: WHO.
26
World Health Organization (2005) Formaldehyde in Drinking-water: Background document for development of
27
WHO Guidelines for Drinking-water Quality, Geneva, Switzerland: WHO.
28