Waste disposal device includes a container, a lid, and a rotation mechanism that rotates a waste-containing member when present in the container. A slide mechanism enables opening movement of the lid to cause the rotation mechanism to rotate the waste-containing member or prevent the rotation mechanism from rotating the waste-containing member depending on its setting. A foot pedal assembly includes a foot pedal and a spring, and causes both opening of the lid when the foot pedal is depressed and closure of the lid when the pressing force is removed. The spring is moved against its bias upon depression of the foot pedal and returns to its original state when the pressing force is removed to cause closure of the lid and rotation of the waste-containing member. The device may be used for medical waste from hospitals, doctors' offices, home health care personnel and facilities, nursing homes, and biohazard laboratories.