Embolism: An embolism is a total or partial blockage of a blood vessel that impedes or stops blood flow. The blockage can be caused by a blood clot, bacteria, air, parasites, bone marrow (from breakage of a major bone) or other bodily or foreign materials. Embolisms can be life-threatening conditions. For example, if a blood clot travels to the heart and blocks blood flow in the vessels supplying the heart muscles, the result could be a fatal heart attack. If this happens in the brain, the result could be a stroke (also called a "brain attack"). Additional Info: A pulmonary embolism is an embolism that occurs in the lung. These are not uncommon in a condition called deep vein thrombosis (DVT) in which blood clots that form in the vessels of the groin or leg break free and travel to the lungs. If left untreated (by blood thinning medications such as coumarin, for example), a pulmonary embolism can be fatal. A thrombosis is a blood clot inside a blood vessel. If it breaks free and creates an obstruction it is then called an embolism. While symptoms of embolisms are often not noted by the victim, certain risk factors for pulmonary embolism are: (1) Immobility for a long period. (2) Having had surgery within the past month or two. (3) Medical history of cancer or heart disease. (4) Deep venous thrombosis. (5) Previous pulmonary embolisms. (6) Pregnancy or use of estrogen. (7) Hypercoagulability (tendency to clot easily). Embolisms can form due to trauma (damage) to the body. For example, a bullet, bone marrow or amniotic fluid could work its way into a blood vessel during an accident and cause an embolism. MSDS Relevance: This term is not commonly found on MSDS's, although we have seen on a few MSDS's, such as those for estrogens or estrogen mimics, that warn of embolisms as possible health hazards. See also: Respiratory System