The stories about the toxicity of liquid mercury are very much overblown, as elemental mercury in liquid form is not absorbed by the body. Mercury vapors can be toxic, but unless heated, mercury volatilizes only very, very slightly at room temperature. The real toxicity problem results from ingestion of soluble mercury compounds. At one time, I had a job that involved my wading in large sumps of liquid mercury - tons of it. I never had any health problems, and that was over 50 years ago. Even earlier, I was a lab technician running mercury nitrometer equipment in a smokeless powder factory, and there was a lot of mercury involved in that testing also. I remember we had a large number of steel flasks of mercury stored in the basement of the lab building which had been taken from a captured WWII Japanese submarine. Their subs used it for ballast.