Easy and quick determination of some trace elements in table salt samples by inductively coupled plasma-mass spectrometry applying aerosol dilution method

Salt (NaCl) is among the most widely consumed food additives and is also used in medicine, dyeing, textile industry etc. Salt samples in the market may contain diverse amounts of metals, depending on its source (sea, lake or mining) and production processes. Trace elements play vital role in biological processes in terms of their essentiality and/or toxicity. Toxic effects of some elements such as nickel on human health are well-known even at trace levels. On the other hand, metals such as zinc, copper and iron which are essential for normal body functions exert toxic effects at high concentrations. Since its importance in human nutrition, salt samples should be routinely analyzed to assure food safety and quality control. Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) has been a method of choice for trace element analysis in many sample types because of its high detection power, relatively compound independent signal response, wide linear range, and also multi element detection capability. However, the interferences from polyatomic species formed in plasma and salt deposition on cones and lens of ICP-MS is a problem for routine analysis of salty solutions. Moreover, high abundance of Na and Cl ions suppresses the ionization of analytes in the argon plasma. This thesis comprises some studies for rapid determination of trace elements in high salt media applying aerosol dilution technique. In this approach, the carrier gas flow is decreased to reduce the formation of sample aerosol which is further diluted by dilution gas prior to its introduction into plasma, allowing direct analysis of high-matrix sample solutions.