FLUORIDE ACCUMULATION BY VEGETATION IN THE VICINITY OF A PHOSPHATE FERTILIZER PLANT IN TUNISIA

Abstract

SUMMARY: Monthly observations from May through October during the year 2000 on the southwest side of a phosphate fertilizer plant located in the coastal zone of the Sfax region of Tunisia showed that vegetation close to the factory accumulates large quantities of F with variable specific symptoms of toxicity. According to their F content, cultivated species can be classified into five different categories. At the same level of exposure, species with high F content include olive trees (420 µg F/g dry weight), while those with low F content are represented by apricot trees (50 µg F/g dry weight). As expected, F concentrations decreased with increasing distance from the pollution source. Beyond 8 km, they were lower than 30 µg F/ g dry weight. Analysis of atmospheric fluoride revealed a close interrelationship between concentrations of F in the atmosphere and in plant leaves.