Popis: |
Adverse health effects of inhaled particulates have been noted for centuries, and studies over the last several decades have linked particle and fiber inhalation to several pulmonary diseases, including fibrosis, silicosis, chronic obstructive pulmonary disease, emphysema, asthma, hypersensitivity pneumonitis, and cancer, as well as cardiovascular disease. Inhaled particles and fibers can produce toxicity through several mechanisms, many mediated by the immune system. Particle and fiber toxicity is influenced by composition, size and shape of the material, as well as surface properties, including surface charge, protein corona, and surface contamination. Dissolution rate within the body can also influence toxicity. Although less extensively studied, some particles and fibers can also produce health effects when ingested and as a result of dermal contact. To help protect against adverse effects of particle and fiber exposure, regulatory agencies in numerous countries have developed exposure limits for airborne particulates in general, as well as for specific particles and fibers of special concern. |