Current techniques used for diatom test in diagnosis of drowning deaths

Diatoms are well known water planktons with variable number of shape and sizes, and they are found in almost all types of water bodies. They (diatoms) are very important in Forensic Science in solving cases where death has occurred due to drowning. When a person drowns in water he tends to grasps for air due to which water along with diatoms enters the lungs, and from lungs into the blood stream and from blood stream the diatoms get lodged into the distant organs of the body. The identification of diatoms is based on the morphology of their structure by using light microscopy or scanning electron microscope. In an investigation of a case in which the body has been recovered from a water body, two preliminary queries arise i.e. whether the drowning is post-mortem or ante-mortem. Since symptoms of drowning diminishes with the passage of time; hence diatom test act as a revival tool in solving the cases pertaining to deaths by drowning. This paper reviews the progress made in the recent years in the diagnosis of diatoms pertaining to deaths by drowning.