Abstract:
Metals, coatings and embalming fluid used in burial practices may corrode and seep
into the soils, which could end up in nearby water sources. However, this basic
assumption has not yet been proven. To avoid other anthropogenic factors, this thesis
comprised of a laboratory study of the leaching potentials of metals and formaldehyde
through different soils under various environmental conditions. After collecting and
analysing the coffin samples, twenty-seven containers with taps were filled with either
sand, silt or clay soils. Samples of burial materials, cloth saturated with formalin and
bacteria were buried within each soil column. These were exposed to high or lower
temperatures and conditions simulating heavy or prolonged rainfall using either
acidic or slightly acid water. Interment continued for six months.
In addition to testing the effects of these variables, cement was buried in the three soil
types with pre-weighed coiled wires of common metals, namely aluminium, iron,
copper and zinc. After 24 weeks of testing, the corrosion rates of the various metals
were determined, which allowed us to conclude that concrete tombs could be a
possible solution to reduce the corrosion rates of coffin materials. It may also retard
soil and groundwater contamination.
After analysing the water leachates of each sample, it became evident that coffin
materials do indeed corrode and become mobile. It also verifies that the
aforementioned variables do in fact affect the corrosion rate and leaching of the
various coffin materials and that concrete tombs truly are a solution to reduce
corrosion and contamination rates of cemeteries. The results also showed that most
formaldehyde percolated through the soil between weeks six to week 14 of interment.
Neither temperature nor pH affected the amount of formaldehyde leachate, however,
conditions simulating heavy rainfall facilitated leaching. Although a total of only 3%
of the initial amount of formaldehyde became mobile, concentrations of up to 15.0 mg/L formaldehyde were recorded on two occasions – considerably higher than
the Tolerable Concentration recommended by the World Health Organization.
