Decomposition Changes in Bodies Recovered from Water

Recovering bodies from water is a common task for any medical examiner or coroner office. Unfortunately, there will be a significant postmortem interval before many of these remains are found. A thorough scene investigation must be undertaken to determine if the location of the death and that of the body recovery are the same. Decomposition in a wet environment differs from that in other settings, both in the changes that occur and the rate at which they occur. It is essential that the forensic pathologist or medicolegal death investigator recognize and appreciate the uniqueness of immersed and submerged remains. The typical decomposition changes proceed more slowly in the water, primarily due to cooler temperatures and the anaerobic environment. However, once a body is removed from the water, putrefaction will likely be accelerated. Postmortem changes are not only affected by water temperature, but also by current as well as obstacles and structures, both natural and man-made, that may interact with the remains. The anaerobic nature of decomposition for wet or submerged remains may result in adipocere formation, a unique and fascinating process that results from incomplete transformation of lipids by bacteria. Insect and animal species feeding on the remains are different for submerged bodies. Postmortem predation may cause external defects that mimic injuries and should be interpreted with care. Forensic pathologists and medicolegal death investigators must be aware of the postmortem changes that may occur with submerged and immersed bodies.