Mercury is one of the most toxic elements known and has devastating effects on the neurological systems of humans and animals alike (Tchounwou et al., 2003; Selin 2009). The water-soluble form, the mercury(II) ion (Hg²⁺) is one of the most prevalent forms of mercury pollution.

Mercury tends to accumulate and become magnified in aquatic food chains (Clarkson et al., 2003; Leopold et al, 2010). As a result, fish and seafood consumption is one of the most important exposure routes for mercury (Al-Mughairi et al., 2013; Greenfield et al., 2013).

Mercury exposure damages a variety of human organs, like the brain and kidney and compromise immune, nervous, and endocrine systems (Clarkson et al., 2003; Nolan and Lippard 2008; de Souza and de Carvalho, 2009; Mutter et al., 2010; Mamdani and Vettese, 2013).

The National Health and Nutrition Examination Survey has found evidence that mercury levels were 4-fold higher in people who ate 3 or more servings of fish per month than in those who did not consume seafood (Schober et al., 2003). Fish that contain higher levels of mercury may harm an unborn baby or young child’s developing nervous system. The U.S. Food and Drug Administration and Environmental Protection Agency advise us that pregnant women, women of child-bearing age, nursing mothers, and young children must completely avoid certain fish and other seafood (Emily et al., 2002), especially shark, swordfish, king mackerel, and tilefish, that contain significantly high levels of mercury (FDA, 2014).

The European Union has set maximum residual limits for total mercury in fish and seafood and most fish processors routinely monitor their seafood for contamination (Maggi et al., 2009) before exporting to this economic region. The Food and Agriculture Organization/World Health organization (FAO/WHO) jointly introduced provisional tolerable intake levels on a weekly basis (PTWI) in several food matrices for total mercury and methylmercury at 5.0 and 1.6 μg/kg/week, respectively over 15 years ago (WHO, 2003). Several nations such as the USA (Lange et al., 1994), the UK (Collings et al., 1996), Australia (Denton and Burdon-Jones, 1996), India (Sivaperumal et al., 2007), and Oman (Al-Busaidi et al., 2011) have recommended a maximum level of 0.5 mg Hg/kg in fish tissue.

The measurement and quantification of mercury ions in contaminated samples is measured nowadays by inductively coupled plasma mass spectrometry (Ugo et al., 2001), high-performance liquid chromatography (HPLC) (Balarama Krishna et al., 2007), atomic absorption spectrometry (Hsu et al., 2011), and electrochemical techniques (Zhu et al., 2009).

These methods offer excellent sensitivity, but their major drawbacks are high cost with complex and time-consuming test protocols. There is a need for development of a simple, rapid, economical, and sensitive method for mercury detection for detecting mercury ions in food and environmental samples (Male et al., 2013; Mansour, 2014; Yasri et al., 2014).

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