Arsenic fed piglets: Assessing arsenic levels in decomposing pig tissues and soil samples

This research developed an instrumental method by which arsenic levels can be successfully detected in decomposing pig tissue. An essential goal of a forensic toxicologist is the analysis of biological matrices for the presence of drugs, metals, and other toxins, as they are important for investigations associated with the potential use of these materials acutely prior to homicidal-death. Currently, there are several methods available for the assessment of heavy metals such as arsenic in human tissue collected during a typical autopsy (Formicki et al., 2010). However, when one considers examining decomposing tissues these tests are limited in their ability to detect heavy metals like arsenic. An experiment has been conducted that potentially allows one to detect arsenic levels in decomposing pig tissue (skin, muscle and bone) as well as from surrounding soil. The purpose of the experiment is to set minimal ranges of arsenic levels in these tissues. The experiment begins with the feeding of arsenic (in the form of potassium arsenate) to 4 piglets; the feeding of arsenic was at sub-lethal concentrations over a 3 day period. The piglets received a total of 2.8 mg/kg amount of arsenic. On the fourth day, the pigs were euthanized. An additional piglet was used as a control animal, it was not fed arsenic. After euthanizing them, all 5 piglets were set out for surface decomposition. Results demonstrated that arsenic concentrations can be identified in skin, muscle, bone, and soil after a three month decomposition period. Furthermore, multi-factor analysis of variance yielded significant effects for the response of arsenic concentration with respect to the decomposition time (p =0.0198) and type of bio-specimen (p = 0.0300) in relation to measured concentration values. There was no observed significant difference across all piglets tested. Arsenic concentrations were much higher in the soil samples collected from underneath the cadaveric area of each piglet, with a peak concentration detected at day 18 of decomposition. Little data specific to how arsenic redistributes postmortem is available, hence the work presented helps in the forensic assessment of acute-toxic antemortem dosages specific to death events.