The use of diatom fingerprinting to determine death in drowning cases

Drowning is one of the major cause of deaths in India. Drowning can be accidental, Homicidal or Suicidal. Drowning is a form of asphyxia death in which breathing is prevented by immersion in a liquid. Presence of fine froth at the mouth or nostrils, petechial haemorrhages, impression of ribs on lungs, oedematous lungs, etc. are Signs of Drowning in freshly retrieved body from waters. However, these symptoms don’t appear in decomposed corpses and skeletonized body.

Here diatom test stands as the only direct screening test for drowning. The principle behind the “Diatom Test” is when drowning takes place the diatoms present in medium, enter through ruptured capillaries via penetration into the alveolar system, subsequently to blood stream and further distant organs and other body tissues, it is here diatom test seeks as golden standard test in forensic investigation to detect antemortem or postmortem drowning. The utility of the diatom test for drowning using femoral bone marrow was calculated in a series of 771 cases of drowning that occurred during the summer, late spring and early autumn in Ontario, Canada. The diatom test for drowning was positive in 205 cases (28%) of the freshwater drowning cases but was rarely positive if drowning occurred in water from a domestic source that lacked diatoms due to water filtration and processing. Only four cases (12%) of domestic drowning had a positive diatom test.

Know about Diatoms Here: Diatoms: A Marvelous Living Organism

The relationship of test outcome with diatom population dynamics is important corroborating evidence for the validity of the test since it is predictable that the diatom content of the water would influence test outcome. The postmortem analysis of drowning is a classical problem in the pathology of sudden violent death. From a historical perspective, one of the most important issues in the study of drowning has been the search for a sensitive, specific and easily applicable test for this cause of death. On this basis, the diatom test has emerged as the foremost laboratory procedure for the detection of drowning. 29 cases of drowning were analyzed and emphasize for the usefulness of the diatom-test to find the manner of death and stressed on the collaboration between forensic pathologists and specialist- biologists, who could work together to generate the diatomologic map of the water bodies of that region. In this way, some rare types of diatoms can be identified and located, which can be of great help in pinpointing the actual site of drowning.

The presence of diatoms can be established and analyzed both quantitatively and qualitatively through a diatom test. This can lead not only to a more direct determination of the cause of death, but also can help to pinpoint the site of a suspected drowning. Continuous monitoring of water bodies for the percentage bloom of diatom flora and its taxonomy is very essential every year. Since due to climate changes there is variability in diatom flora, which serves as an effective tool to diagnose death due to drowning. Many times, body get drifted to some other place either due to water current or otherwise. In such cases if a thorough monitoring of diatom flora of a particular body is recorded, it becomes possible to locate site and season of drowning. For this purpose, database of most commonly occurring, site specific, and seasonal occurring diatoms was constituted along with the shape and size resulting into the formation of a fingerprinting system for diatoms.

Few Commonly Occurring Diatoms
Few Commonly Occurring Diatoms
Few Least Occurring Diatoms
Few Least Occurring Diatoms
Few Seasonal Diatoms
Few Seasonal Diatoms

Citation: Vinayak V, Mishra V, Goyal MK (2013) Diatom Fingerprinting to Ascertain Death in Drowning Cases. J Forensic Res 4: 207. doi:10.4172/2157-7145.1000207

References

  • He F, Huang D, Liu L, Shu X, Yin H, et al. (2008) A novel PCR-DGGE-based method for identifying plankton 16S rDNA for the diagnosis of drowning. Forensic Sci Int 176: 152-156.
  • Pollanen MS, Cheung C, Chiasson DA (1997) The diagnostic value of the diatom test for drowning 1. Utility: a retrospective analysis of 771 cases of drowning in Ontario, Canada. J Forensic Sci 42: 281-285.
  • Pollanen MS (1998) Forensic Diatomology and Drowning. Elsevier, Amsterdam, The Netherlands 1-157.
  • Natasha D, Aleksej D (2005) Differential diagnostic elements in the determination of drowning. Rom J Leg Med 13: 22-30.
  • Ludes B, Coste M, North N, Doray S, Tracqui A et al. (1999) Diatom Analysis in Victim’s Tissues as an Indicator of the site of Drowning. International Journal of Legal Medicine 112: 163-166.