Determination of Thiocyanate within Physiological Fluids and Environmental Samples: Current Practice and Future Trends

Abstract

As the toxicological and physiological importance of thiocyanate has become more and more evident during the past 20 years, there has been an increasing interest in this anion. Thiocyanate is a detoxication product of cyanide and its content in human saliva is considered as a biomarker for identification of nonsmokers and smokers. Chronically elevated levels of thiocyanate in body fluids are known to be toxic and its relation to local goiter, vertigo, or unconciousness has been pointed out. On the other hand, thiocyanate-containing waste discharged into rivers is harmful to aquatic life due to its degradation to cyanide in the presence of oxidants. Therefore, precise knowledge of the thiocyanate content in biological fluids and environmental samples is mandatory. An overview of the existing analytical methodologies for thiocyanate is presented and their advantages and limitations are highlighted. This review is intended not only to provide a comparison of the different methods employed, but also to make it possible for the interested reader to quickly find developments and relevant work that have transpired over the past 10 years.

Keywords:

• anions
• biological fluids
• cyanide
• environmental samples
• thiocyanate analysis

Acknowledgments

The authors thank Dr. Recalde Ruiz who contributed to the work described herein. Dr. Mayra Granda Valdés is grateful to the University of Oviedo and the University of Havana for support provided through the International Exchange Programme during fall 2002.