Mineral dust exposure and systemic diseases.

Based on clinical and immunological studies, we have proposed the hypothesis that occupational dust exposure might cause not only pneumoconiosis but also autoimmune diseases and malignancies of various organs such as neoplasms of lymphatic and hematopoietic tissues and gastric cancer. Evidence from cohort studies of pneumoconiotic patients in Japan, copper miners, and stone masons support our hypothesis. The carcinogenicity and cytotoxic effect of inhaled dust on immune cells are considered to contribute to the development of these diseases.