196 The American Journal of Forensic Medicine and Pathology 22(2):196–199, 2001. ©2001 Lippincott Williams & Wilkins, Inc., Philadelphia Autopsy reports at the Forensic Science Centre, Ade- laide, South Australia, were reviewed for the 8 years from January 1991 to December 1998 for cases with un- usual features in which deaths had been attributed to ex- posure to high environmental temperatures. Ampheta- mine-related hyperpyrexial deaths, anesthetic deaths caused by malignant hyperpyrexia, deaths of elderly in- capacitated individuals during heat waves, and deaths of children trapped in the back of cars were excluded from the study. In 9 cases, where heat-related deaths had oc- curred (age range 21 to 77 years; M:F = 8:1). Predispos- ing factors included lack of familiarity with Australian environmental conditions, excessive clothing, prolonged sun exposure, acute alcohol intoxication, obesity, ben- ztropine and trifluoperazine medication, and underlying dementia, alcoholic liver disease, and possibly epilepsy. Key Words: Heat-related deaths—Hyperthermia. In Australia, as in other parts of the world, com- mon scenarios resulting in death from prolonged exposure to high ambient temperatures include physical illnesses in elderly individuals during heat waves, and leaving children in cars (1). The follow- ing cases are reported to demonstrate a range of al- ternative circumstances that may predispose to en- vironmental hyperpyrexial deaths, with comments on difficulties in autopsy diagnosis. MATERIALS AND METHODS Autopsy reports at the Forensic Science Centre, Adelaide, South Australia, were reviewed for the 8 years from January 1991 to December 1998 for cases in which heat-related deaths had been attrib- uted to exposure to high environmental tempera- tures. Amphetamine-related hyperpyrexial deaths, anesthetic deaths caused by malignant hyper- pyrexia, deaths of elderly incapacitated individuals during heat waves, and deaths of children trapped/left in cars were excluded from the study. Files were examined, and details of the age and sex of the victims, the circumstances surrounding the fatal episodes, the maximum ambient temperature, the location of the deaths, the autopsy findings, and any ancillary reports on toxicology were docu- mented. CASE REPORTS Case 1 A 21-year-old man was found dead under a tree at the base of a cliff. It appeared from inspection of the that he had slipped from the top of the cliff and fallen 20 meters into soft sand. He had subse- quently removed some of his clothes at the point of impact, and marks in the sand indicated that he had dragged himself to beneath the nearest tree. There were no marks in the sand to indicate the presence or involvement of other individuals. The maximum An Analysis of Factors Contributing to a Series of Deaths Caused by Exposure to High Environmental Temperatures Helen Green, B.Med.Sci., John Gilbert, F.R.C.P.A., Ross James, F.R.C.P.A., and Roger W. Byard, M.D. Manuscript received April 24, 2000; accepted August 21, 2000. From the Forensic Science Centre, Adelaide, Australia. Address correspondence to Roger W. Byard, M.D., Forensic Science Centre, 21 Divett Place, Adelaide 5000, Australia; e-mail:byardr01@forensic.sa.gov.au.