Not quite true. The Soviet-era labs were certainly not up to that standard at the end of the Cold War,
There are NO BSL-4 labs in Ukraine. Period.
Known as biosafety level 4 (BSL4) labs, these are designed and built so that researchers can safely work with the most dangerous pathogens on the planet – ones that can cause serious disease and for which no treatment or vaccines exist. Researchers are required to wear full-body pressurised suits with independent oxygen.
https://theconversation.com/fifty-nine-labs-around-world-handle-the-deadliest-pathogens-only-a-quarter-score-high-on-safety-161777
“There are NO BSL-4 labs in Ukraine. Period.”
I’m not disputing that. What I am saying is that none of the labs in Ukraine were up to any BSL safety protocol at all until after the Soviet Union fell and we began to help them upgrade the labs. However we were not granted full access to at least one facility, the Melnikov AP facility in Odessa, which is one of the 2 labs in Ukraine that was dealing with the most deadly pathogens. The inspectors reported that they were only able to inspect the outside security measures at that lab and not the lab itself.
I believe Ukraine later, after 2005, upgraded that lab to BSL-3 without direct Western participation. So we have no way of knowing what is contained in that lab, whether it is BSL-4 or not.