**4. Methods for inorganic arsenic determination in food and beverages**

Inorganic arsenic determination could be performed applying a number of methods (WHO, 2011). Some of them, such as the spectrophotometric analysis with silver diethyldidhiocarbamate and certain modifications of the atomic absorption spectrometry (AAS) and the inductively coupled plasma (ICP) are standardised (DIN 38405-D12; APHA/AWWA/WPCF 3500-As C; AOAC 33.125-33.132 in combination with 25.041 and 25.042; EPA 7061; DIN 38405-D1; APHA/AWWA/WPCF 3500-As B: 3114 B; APHA/AWWA/WPCF 3500-As E: 3120 B; DIN 38406-E22) and are among the mostly applied for arsenic determination in food and beverages (Bingöl et al., 2010; Conklin, 2010; Husáková et al., 2007; Karadjova et al., 2005; Niu Jianjun & Wang Bingwu, 1992; Roberge et al., 2009; Stafilov et al., 2004; Syr-Song Chen et al., 2003; Tašev et al., 2005). Nevertheless, arsenic is one of the few elements for which AAS is not enough sensitive. Using special supplies such as arsine generators and electrothermal analysers allows lowering the detection limit, but causes difficulties in the routine analysis. The other advanced instrumental methods such as ICP, neutron activation analysis (NAA), and X-ray

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**Arsenic intake, g/day**

Fig. 1. Average daily arsenic intakes for various countries (Arsenic. WHO Food Additives

**3. Sample collection, preparation and treatment for arsenic determination in** 

Sample collection, preparation and treatment for arsenic determination in food and beverages are performed according to the established procedures (WHO, 2011). These include: collection of samples, representative of the food consumed in a population; sample conservation in acid washed plastic containers; freezing of samples if necessary, to -80oC; food preparation or cooking in a manner similar to those that would be used at home, if appropriate; sample homogenization and digestion, applying various techniques guided by

**4. Methods for inorganic arsenic determination in food and beverages** 

Inorganic arsenic determination could be performed applying a number of methods (WHO, 2011). Some of them, such as the spectrophotometric analysis with silver diethyldidhiocarbamate and certain modifications of the atomic absorption spectrometry (AAS) and the inductively coupled plasma (ICP) are standardised (DIN 38405-D12; APHA/AWWA/WPCF 3500-As C; AOAC 33.125-33.132 in combination with 25.041 and 25.042; EPA 7061; DIN 38405-D1; APHA/AWWA/WPCF 3500-As B: 3114 B; APHA/AWWA/WPCF 3500-As E: 3120 B; DIN 38406-E22) and are among the mostly applied for arsenic determination in food and beverages (Bingöl et al., 2010; Conklin, 2010; Husáková et al., 2007; Karadjova et al., 2005; Niu Jianjun & Wang Bingwu, 1992; Roberge et al., 2009; Stafilov et al., 2004; Syr-Song Chen et al., 2003; Tašev et al., 2005). Nevertheless, arsenic is one of the few elements for which AAS is not enough sensitive. Using special supplies such as arsine generators and electrothermal analysers allows lowering the detection limit, but causes difficulties in the routine analysis. The other advanced instrumental methods such as ICP, neutron activation analysis (NAA), and X-ray

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Korea China Japan UK

Series 18)

**food and beverages** 

the subsequent analysis technique.

Germany Scotland Canada Austria fluorescence permit the determination of arsenic at trace levels, but they require expensive and sophisticated equipment. The spectrophotometric methods, although simple and cost effective, do not provide the required sensitivity.

The electrochemical methods for inorganic arsenic determination (Cavicchioli et al., 2004), including mainly anodic stripping voltammetry and differential pulse polarography, in spite of their limited application in food quality control, could be considered as an alternative to the above mentioned analytical techniques. For instance, their sensitivity is similar to this of mass spectrometry and NAA, but they are much more simple, require low costing equipment, and allow distinguishing the electro-active As(III) and the electroinactive As(V), in contrast to the enumerated techniques. As(III) and As(V) have different toxicity, biological activity, and physiological action. The toxicity of As(III) is known to be greater of that of As(V). Thus, the distinction between the two forms is of primary importance.

The further development of the electrochemical methods is associated with the appearance, during the 1960s, of the so-called electrochemical biosensors. They combine the high sensitivity, accuracy and reproducibility of the electrochemical analysis with the substrate specificity and catalytic activity of the biological molecules. A number of them found an application in food industry, namely in food safety and quality control, and in the control of the fermentation processes (Mutlu, 2010; Scott, 1998; Prodromidis & Karayannis, 2002; Wagner & Guilbault, 1994).
