Study on the postmortem submersion interval and accumulated degree days for a multiple drowning accident

Recreational accidents in aquatic environments leading to death by drowning are quite frequent. Even if they do not usually require forensic investigation, they may provide useful information on the post mortem submersion interval (PMSI) and its relation with accumulated degree days (ADD). This is particularly useful to forensic science since most studies dealing with these matters rely mostly on animal carcasses as human analogues. In this work we report on a multiple drowning accident resulting in 6 victims. ADD was calculated based on the PMSI and water temperature during this period. PMSI varied between ∼7.4 days and ∼11.4 days, and estimated body drift from the accident site ranged from 0.5km to 8.0km. Surface water temperature in the accident area showed little variation during the PMSI (14.5-16.0°C). Estimated ADD varied between 115°C and 174°C, and between 104°C and 191°C when considering the cumulative lower (ADDmin) and upper (ADDmax) limits for ADD. We compare the results with recently published data on two similar cases, and suggest a range for ADD that can be assumed as necessary before body floatability is regain after a drowning accident.