This document is a review of occupational and environmental exposure to selected synthetic organic fibres. The particular fibres covered in this document have been selected because they are the only ones for which some toxicological data are available, and they are probably of most importance in terms of production volumes and potential for human exposure. Carbon/graphite fibres are filamentary forms of carbon produced by high-temperature processing of one of three precursor materials: rayon (regenerated cellulose), pitch (coal tar or petroleum residue) or polyacrylonitrile (PAN).