Iodine concentrations of soils near Trabzon, Turkey: a region of endemic goiter

Ciftci E., Sevketbeyoglu E. (., Tokel S.

ENVIRONMENTAL GEOLOGY, vol.53, no.2, pp.457-465, 2007 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 53 Issue: 2
  • Publication Date: 2007
  • Doi Number: 10.1007/s00254-007-0661-6
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.457-465
  • Kocaeli University Affiliated: No


Iodine contents of soils developed over the major rock formations of the northern zone of the Eastern Pontide Tectonic Belt (Northeastern Turkey) have been investigated with respect to soil-parent rock relationship, effect of topography, elevation, and climate to construe its effect on the health of the local population. Samples were collected from the A and B horizons of the soils developed over the major stratigraphic units constituting the eastern Pontides, including the Lower Basic Complex of Jurassic-Lower Cretaceous age, the Berdiga limestone (Jurassic-lower Cretaceous), the Dagbasi granitoid (Upper Cretaceous), volcano-sedimentary sequence of Upper Cretaceous age, ore-bearing and barren dacites of Upper Cretaceous age, and Neogene alkaline basalts. Chemical analyses of soil samples indicate significantly lower iodine abundances for all the soils studied (5-28 ppm) in comparison to the average abundance of iodine in analogous soils of other parts of the world (22-93 ppm). The concentration of iodine in soils developed over the same geologic formation decrease with increasing elevation. In certain cases, this decrease may reach up to 70%. Goiter is highly common throughout this region in Turkey. The results of this study suggest that the iodine deficiency of region's soils may be a principal underlying cause for this area of Turkey being an endemic goiter region.