Inhaled metallic (fluid) mercury (Hg°) especially of heated mercury acts mainly as a neurotoxicant. Mercury vapor or fumes are particularly toxic when fluid mercury is heated and boils in a confined space. ARDS and fatal respiratory failure may develop. ARDS may affect several family members when Hg-containing material (fluid Hg, amalgams) is heated in the home or occupational setting. Heated mercury (boiling point 356,7°C) is particularly noxious. Injected fluid mercury in Munchausen syndrome, illicit drug abusers or secondary to breakage of old pressure sensors may lodge in the pulmonary circulation causing distinctive imaging features. Review on the toxic effects of environmental mercury at PMID 24744824