why do toxicology reports take so long?


It seems like if someone goes into an emergency room, they can get a toxicology report super fast depending on the emergency but if someone dies the toxicology report takes months. Why is that?

In: 15

Because the lab prioritizes the ER patients. In addition, there is no “oops, go get another sample” in an autopsy so they have to be very careful and test more selectively across a broader group of possible toxins as this report will become the “permanent record”.

Obviously, finding out what is affecting a living person, who could be saved/healed is of more urgency than discovering someone’s cause of death. It’s just prioritization.


The tests run in hospital test for the common offenders: opioids, thc, meth, benzos…

They are run using blood and/or urine samples. The general idea is if they are actively suffering effects of the toxin, it is likely actively circulating in their body and you will find it there. Also, having a live patient to help you rule out possibilities about what they may have ingested helps narrow it down. But you are not getting a complete “tox screen.” Those don’t exist.

Post-mortem, the blood is clotted, there may not be much urine, and we don’t know if they died from an active circulating toxin, or the effects of the toxin (liver failure, kidney failure, arrhythmia), thus all possible tissues are tested for many possible toxins, and typically tested in a staged manner, the most likely/common being tested first, then gradually testing the more odd or less common toxins. These tests cost a lot of money and need to be run individually on their own piece of tissue.

In a live patient, if the standard toxicology report is negative, then they need to sample other organs, which means taking a biopsy of the liver/kidney/whatever, which usually involves surgery and taking as little as possible to minimize the potential complications of the surgery.

In a deceased patient, you can take the whole liver. Both kidneys. Whole heart. And run tests until you run out of money or body parts.

Typically, hospitals only test for the presence of certain substances. It’s a very limited and generalized list. It tests for “opioids”, benzodiazepines, or cannabinoids, as opposed to specific drugs.

More in depth quantitative tests with identification take longer and are only done a certain labs.

There’s also chain of custody issues when dealing with legal cases, as well as a backlog at crime labs.