The opioid epidemic was in full swing when I was sworn in as a coroner in January of 2018. Even though I’m a doctor, interpreting the complex postmortem toxicology reports landing on my desk involved a steep learning curve. Dead bodies, it turns out, are not the same as living bodies when it comes to chemistry.
In this first-in-a-series post about what I wish I’d known then about interpreting toxicology reports, I’m going to cover ethanol.
There are other alcohols that can kill you, but ethanol (alcohol to most of us) is by far the most common poison we like to put in our bodies. That’s assuming we agree that caffeine is not a poison.
First, let’s get a few things out of the way. Like, what does a toxicology report look like?
Anatomy of a toxicology report
This is a fairly simple report with only legal substances found and peripheral blood tested. In most cases, peripheral blood is the preferred source for tox testing. Peripheral means the blood was collected away from the heart, usually the femoral blood vessels.
Presumptive positive results on a urine sample are rarely useful for forensic purposes. I learned to ignore them.
It’s also common to test vitreous “humor”, the clear liquid extracted from the eye. This was a new one to me. For obvious reasons, we don’t collect vitreous in living humans. In the postmortem setting, it’s useful for measuring glucose and electrolytes. The results can diagnose conditions like diabetes mellitus or dehydration.
Next, let’s cover a few compounds that show up often but can usually be ignored.
The (usually) innocent bystanders
See how caffeine shows up on the report above? Caffeine may be the most popular drug in the United States, but as far as I know it’s never killed anyone. There are rumors that in moderation (of course) it may be good for you.
Nicotine is less commonly found in tox reports than caffeine. The cotinine on the report above is a breakdown product of nicotine. Tobacco is a “slow killer.” It wouldn’t be out of order to list tobacco use/abuse as a contributing factor on a death certificate for something like chronic obstructive lung disease. But not on the basis of a single toxicology test. Instead you’d be looking at the medical and social history to confirm decades of tobacco product use.
In my February 2025 newsletter, I wrote about how nicotine could also be an acute poison. It’s a pesticide, after all. Forensic toxicologist James Wigmore warns that high-nicotine e-cigarette liquids “may be a forerunner to further use of this poison.”
Cannabis in postmortem toxicology reports
Maybe you noticed the Delta-9 THC in the sample toxicology report. It is the psychoactive cannabinoid in marijuana. Sometimes tests show 11-hydroxy THC, an inactive metabolite. It is not possible to determine from these tests when or how much cannabis was ingested or inhaled.
Although toxicology tests frequently find cannabinoids, most coroners and medical examiners will not list them as contributing to a death.
A possible exception might be listing cannabinoid intoxication as a contributing factor in a fatal motor vehicle collision, assuming no other cause is found.
Three cases: Interpreting alcohol in postmortem toxicology reports
Toxicology test results must always be interpreted in the context of terminal events in the decedent’s life, their medical and social history, and autopsy findings.
Details in these cases have been changed to maintain privacy.
Case 1. Alcohol and benzos: A dangerous combo
A man in his late thirties was found dead at home with no evidence of trauma. According to friends, he’d been partying the night before and they had driven him home because he was too intoxicated to drive. The autopsy found no medical conditions to account for his death.
The sample report above shows his toxicology results. The blood alcohol concentration (BAC) is 0.441 g/100 ml, high enough to be fatal alone, but more so because mixed with Xanax.
Cause of death: acute alcohol and benzodiazepine intoxication. Manner of death: Accidental
Case 2. Where did the alcohol come from?
EMS was unable to resuscitate a four-month-old previously health baby after his mother called 9-1-1 when she noticed he wasn’t breathing. The baby was on his stomach when found in a bassinet with a pillow and blanket. Rigor mortis was almost complete, indicating it had been hours since the child had died.
An autopsy was negative, but the toxicology report noted a BAC of 0.02% (20 mg/dL) in peripheral blood. Puzzled as to how to interpret this surprising finding, I consulted the lab’s toxicologist.
The answer: While it was possible someone had given the baby alcohol, there was no evidence to confirm this. According to the toxicologist, decomposition of the body could have produced this low level of alcohol.
Don’t hesitate to consult with the toxicologist at the testing lab!
Cause of death: Sudden Unexpected Infant Death with Extrinsic Factors (prone sleep and bedding). Manner of death: Could not be determined
Case 3. Where’s the alcohol?
Family members found a forty-eight year old man dead in his apartment after they couldn’t reach him by phone. There was no sign of trauma at the scene but he was severely jaundiced. He had a long history of alcohol abuse with cirrhosis and other complications of alcoholism documented in his medical record. The autopsy confirmed advanced cirrhosis and cardiomyopathy but there was no alcohol in his system when he died.
It is not unusual for chronic alcoholics to die with no alcohol on board. In this case, there were two likely causes to consider: alcoholic ketoacidosis or a fatal dysrhythmia due to alcoholic cardiomyopathy. Analysis of vitreous confirmed ketoacidosis (high level of betahydroxybutyrate)
Cause of death: Alcoholic Ketoacidosis due to Chronic Alcoholism. Manner: Natural
Questions about a postmortem toxicology report?
More questions? I offer my newsletter subscribers a free 30-minute consultation on this or other topics I’ve covered in my blog. I will point you in the right direction if I can’t help. You can sign up for my newsletter or contact me here.
Resources
The following are worth reading if you want or need to do a bit more digging into postmortem toxicology.
- Excellent overview article by James R. Gill, Chief Medical Examiner of Connecticut
- Academic but accessible book chapter on forensic toxicology (Graham R. Jones)
- Scientific article on interpreting ethanol results in postmortem specimens (F.C. Kugelberg and A. W. Jones)
- Good explanation of postmortem distribution (Vanessa Fitkanis)
Featured Image Credit: Henryk Niestrój from Pixabay