Respirable Quartz

**Semantic type:** Hazardous or Poisonous Substance

**Definition:** A widespread, naturally occurring, crystalline metal oxide, and is a component in most rocks. Respirable quartz is found in metal and nonmetal mining and milling operations as well as in industries of foundry, granite, ceramic and stone. Inhalation exposure to respirable quartz causes chronic silicosis, emphysema, lymph node fibrosis and is associated with an increased risk of developing lung cancer. (NCI05)