A portable cart for containing medical waste, the cart including: a mobile base; a frame attached to the base that is located above the base, the frame having an outer surface and an opening, the frame shaped to removably hold a bag so that the bag is held open within the frame opening; and a bag tensioner mounted to the frame, said bag tensioner having at least one member mounted to the frame that is adapted to engage a portion of the bag that extends over the outer surface of the frame so that at least a portion of the bag is placed in tension around a section of the outer surface of the frame, said portable cart being characterized in that is said bag tensioner further includes: at least one first pin mounted centrally to a base plate which is adapted to be in rotating abutment with the frame at a fixed location, wherein a first portion of the periphery of the bag is to be routed around the at least one first pin; and wherein the at least one member of the bag tensioner is a bag catch that is mounted to said base plate and extends outwardly therefrom so as to rotate around said at least one first pin, and a second portion of the periphery of the bag is to be placed around the bag catch, said bag catch being located relative to said at least one first pin so that the movement of the bag catch with the second portion of the periphery of the bag mounted thereto places the first portion of the periphery of the bag when routed around the at least one first pin in tension around the at least one first pin so that the periphery of the bag is tensioned around the frame. a mobile base; a frame attached to the base that is located above the base, the frame having an outer surface and an opening, the frame shaped to removably hold a bag so that the bag is held open within the frame opening; and a bag tensioner mounted to the frame, said bag tensioner having at least one member mounted to the frame that is adapted to engage a portion of the bag that extends over the outer surface of the frame so that at least a portion of the bag is placed in tension around a section of the outer surface of the frame, said portable cart being characterized in that is said bag tensioner further includes: at least one first pin mounted centrally to a base plate which is adapted to be in rotating abutment with the frame at a fixed location, wherein a first portion of the periphery of the bag is to be routed around the at least one first pin; and wherein the at least one member of the bag tensioner is a bag catch that is mounted to said base plate and extends outwardly therefrom so as to rotate around said at least one first pin, and a second portion of the periphery of the bag is to be placed around the bag catch, said bag catch being located relative to said at least one first pin so that the movement of the bag catch with the second portion of the periphery of the bag mounted thereto places the first portion of the periphery of the bag when routed around the at least one first pin in tension around the at least one first pin so that the periphery of the bag is tensioned around the frame. at least one first pin mounted centrally to a base plate which is adapted to be in rotating abutment with the frame at a fixed location, wherein a first portion of the periphery of the bag is to be routed around the at least one first pin; and wherein the at least one member of the bag tensioner is a bag catch that is mounted to said base plate and extends outwardly therefrom so as to rotate around said at least one first pin, and a second portion of the periphery of the bag is to be placed around the bag catch, said bag catch being located relative to said at least one first pin so that the movement of the bag catch with the second portion of the periphery of the bag mounted thereto places the first portion of the periphery of the bag when routed around the at least one first pin in tension around the at least one first pin so that the periphery of the bag is tensioned around the frame.