| The U.S. is a leading producer of phosphate rock for processing, with a large portion of mining and production occurring in central Florida. Florida phosphate mining and beneficiation operations currently provide about 75% of the national supply of phosphate-based fertilizers and 25% of the world supply. This constitutes a multi-billion dollar economic investment in the state with over 6000 jobs provided directly by the industry and as many as 30,000 additional positions in transport, shipping, and other service industries.;Potential occupational exposures associated with phosphate mining and beneficiation include sulfuric and phosphoric acid mists2, other mists and dusts containing phosphate, ammonium, fluoride, respirable silica, and technically enhanced naturally occurring radioactive materials (TENORM)3.;While the possible association between phosphate mining and beneficiation and excesses in cancers, specifically lung cancer and leukemia, has been studied, job exposure metrics have not been included. The goal of this study was to produce a job exposure matrix (JEM) based on exposure data (collected at four central Florida Phosphate fertilizer plants and one ore mining and beneficiation plant), positions held, regulatory and process changes, and the implementation and use of engineering controls and PPE. Because of limited exposure data, many of these factors could not be investigated. The resulting JEM was constructed based on job titles found in company records and cross referenced with industry job descriptions for assignment to similar exposure groups. These groups were then assigned a qualitative exposure rating based on data comparisons of two industrial hygiene surveys conducted in the Florida phosphate fertilizer industry. The JEM will be used by NIOSH researchers to reexamine the cohort of phosphate workers originally assembled by Stayner et al.1.;1–3. Please see thesis for references. |
