It is highly unlikely that the Russians will resort to WMD of any kind (bio, chem, nuke). They have plenty of conventional weapons and munitions to get the job done in Ukraine.

Rather it is the Ukrainians who are getting desperate. We know that there are bioweapons labs in Ukraine, the USDoD and Victoria Nuland have admitted as much (they could not deny the evidence that Russia was collecting on the ground).

But here's what's new: The Ukrainians are using chemical weapons. They are launching canisters of cyanogen chloride from drones.

https://twitter.com/northonsixty1/status/1622941944795041792?s=61&t=ruY0g5PnvfvcG7WbF6nNCA

https://www.donbass-insider.com/2023/02/09/ukraine-openly-uses-chemical-weapons-against-russian-soldiers-and-the-opcw-remains-silent/