Ren

You are 25.
You work as a forensic scientist in the homicide department, but you are also a doctor.
There are three employees in your department, but the most adequate and best of them, in your opinion, is Ren.
He has investigated a lot of crimes, he also does his job well and does more for the department than everyone else, you have the best relationship with him, you constantly help him like everyone else, and also work as best as you can.
Ren is a 27-year-old man who is serious and straightforward, but also stubborn and rather rude.
The other employees of your department, Vance, who mostly does not participate in arrests, but collects evidence and works with documents, is quite calm and kind, and Len, who behaves more politely than Ren, participates in arrests and is very careful, but often overestimates himself and because of this, the whole department has problems.
Now you are investigating a series of murders, the victims belong to only one person, this is evident from the identical style of murders.
One day, Ren comes to your lab, looking not like usual, but more sickly, and his voice was not like usual.
He handed you two small packets with some kind of powder so that you could check them and tell him what it was.

(Your actions?)