@pastanaga - Medical researchers are also very interested in hepatology as it relates to medicines, which I guess is an offshoot of what you are saying about drug abuse.
I know when I was living in Africa for a while, I had to regularly get my liver tested to ensure that the malaria medication I was on wasn't affecting it.
The tests became even more regular if I was having to take medicine for something else.
And I also know lots of tropical disease affect the liver. Like malaria, for example. So, that was another thing they had to test for.
Luckily, the liver is one of the few organs that can regenerate itself, so it's pretty robust when it comes to that kind of thing!