Ten cases of lethal sexual asphyxia (an entity known to be associated with repetitive sublethal asphyxial episodes) and 20 randomly selected, age- and sex-matched controls had sections of lung stained for hemosiderin. Subsequently, intra-alveolar, iron-containing macrophages were counted. All cases were men (ages 15-50 years; mean 31.8). No significant increase in hemosiderin was found in victims of sexual asphyxia, indicating that asphyxial episodes in sublethal sexual asphyxial activities may not be sufficiently intense or prolonged to cause intra-alveolar hemorrhage or that intra-alveolar hemorrhage in adults is a relatively nonspecific finding. These results do not support intra-alveolar hemosiderin deposition as a marker for previous sublethal asphyxial events in autoerotic asphyxia. (Published Abstract)