is gaseous mercury poisonous
But the real dangerous property of mercury is its density. 13.5 times denser than water, its liquid and gas forms are highly poisonous. When inhaled or ingested, Mercury can accumulate in the body, slowly degrading the membranes of important organs like the brain, nervous system, kidneys or liver.ercury is the only metal that is liquid at standard temperature and pressure: in fact it is the metal that can remain liquid in the widest range of conditions.