Unusually high levels of hexachlorobenzene (HCB) were detected in the air and in sera of volunteers of a village located in the vicinity of an organochlorinated-compounds factory (Flix, Catalonia, Spain). A significant increase for specific causes of death was obtained only for neoplasms of unknown origin. However, an excess of incident cases was observed for thyroid neoplasms, soft-tissue sarcoma and brain neoplasms in men. These descriptive findings are in agreement with previously reported associations between soft-tissue sarcoma and human exposure to organochlorinated compounds, as well as with animal experiments relating HCB and thyroid cancer, and add new information on the possible relation between organochlorinated compounds, and particularly HCB, and cancer.