Mercury Speciation in Fish Tissues from a Mediterranean River Basin: The Tagus River (Central Spain) as a Case Study

Department of Analytical Chemistry and Food Technology, Faculty of Chemistry, University of Castilla-La Mancha, Ciudad Real, Spain.
Archives of Environmental Contamination and Toxicology (Impact Factor: 1.9). 04/2011; 61(4):642-52. DOI: 10.1007/s00244-011-9666-y
Source: PubMed


An assessment of mercury (Hg) accumulation in fish from the Tagus River aquatic system (central Spain), which has been influenced by pollution from industrial and urban development, was performed. Total Hg (THg), inorganic Hg (IHg), and monomethylmercury (MMHg) were determined in muscle and liver of different fish species, including Cyprinus carpio, Ameiurus melas, and Chondrostoma miegii, sampled from three locations. Although concentrations of THg and Hg species showed wide variability among the fish species, they were also found to be considerably dependent on location and fish tissue. Relative contents of MMHg to THg in muscle varied from 60 to 88%, whereas those found in liver ranged from 7 to 59%. Mean THg concentrations ranged from 126 to 810 ng/g (dry weight [dw]) in liver and from 159 to 1057 ng/g dw in muscle. Therefore, the mean THg concentration in all fish muscle samples was far lower than the maximum residue level recommended by the European Union for fishery products. Nevertheless, the concentrations of Hg in fish muscle reported in this study were somewhat increased compared with other areas geographically distant from most major anthropogenic Hg sources and, in some cases, even greater than those previously reported elsewhere in more polluted areas. In contrast, Hg contents in liver were lower than those found in Hg-contaminated areas, but they were within the range found in other areas exposed to diffuse sources of pollution by Hg. Thus, this article provides an overview of the concentration and distribution of Hg species in fish muscle and liver tissues samples taken from a freshwater system in the Mediterranean River basin.

Download full-text


Available from: María Jiménez-Moreno,
32 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: This paper reports the method development for the simultaneous determination of methylmercury (MeHg+) and inorganic mercury (iHg) species in seafood samples. The study focused on the extraction and quantification of MeHg+ (the most toxic species) by liquid chromatography coupled to on-line UV irradiation and cold vapour atomic fluorescence spectroscopy (LC-UV-CV-AFS), using HCl 4 mol L−1 as the extractant agent. Accuracy of the method has been verified by analysing three certified reference materials and different spiked samples. The values found for total Hg and MeHg+ for the CRMs did not differ significantly from certified values at a 95% confidence level, and recoveries between 85% and 97% for MeHg+, based on spikes, were achieved. The detection limits (LODs) obtained were 0.001 mg Hg kg−1 for total mercury, 0.0003 mg Hg kg−1 for MeHg+ and 0.0004 mg Hg kg−1 for iHg. The quantification limits (LOQs) established were 0.003 mg Hg kg−1 for total mercury, 0.0010 mg Hg kg−1 for MeHg+ and 0.0012 mg Hg kg−1 for iHg. Precision for each mercury species was established, being ≤ 12% in terms of RSD in all cases. Finally, the developed method was applied to 24 seafood samples from different origins and total mercury contents. The concentrations for Total Hg, MeHg+ and iHg ranged from 0.07 to 2.33, 0.003–2.23 and 0.006–0.085 mg Hg kg−1, respectively. The established analytical method allows to obtain results for mercury speciation in less than 1 one hour including both, sample pretreatment and measuring step.
    Food Control 12/2014; 46:351–359. DOI:10.1016/j.foodcont.2014.05.054 · 2.81 Impact Factor