Development and validation of a method for the determination of Hg in animal tissues (equine muscle, bovine kidney and swine kidney, and poultry muscle) by direct mercury analysis (DMA)

• A method sensitive, with low limits of detection and quantification for the determination of trace levels of Hg in animal tissues by DMA.
• Simplicity and high efficiency without the need for any sample preparation procedure.
• Inadequate exposition of animals to the Hg can lead to accumulation this contaminant in animal tissues to consumption.

Mercury is a toxic metal persistent in the environment that has the tendency to accumulate and reaches the food chain. In this study, in order to assess the risk of mercury to humans due to consumption of animal origin food, a rapid and simple method for the precise and accurate determination of trace levels of total mercury in animal tissues by DMA was developed and validated. The Hg quantification was performed about 225.0 mg of sample without any pre-treatment using an elemental mercury analyzer (DMA-80). This method was validated for Hg analysis in the range of 2 ng to 150 ng of Hg with concentrations of 8.9 μg kg− 1 to 667 μg kg− 1. The recovery values obtained showed averages of 98.9% to 106.1%. The detection and quantification limits were determined as 2.7 μg kg− 1 and 8.9 μg kg− 1, respectively. Repeatability and within-laboratory reproducibility were evaluated through the HORRATr and HORRATR indicator and the results were less than 0.15. The method is fast and simple and showed adequate precision and accuracy for the determination of Hg in animal tissues (equine muscle, bovine kidney and swine kidney, and poultry muscle). The method showed standard measurement uncertainty in analytical concentration (32.71 μg kg− 1) below the maximum standard measurement uncertainty (66.72 μg kg− 1). The results obtained showed that the method is simple, fast, and sensitive and showed adequate precision and accuracy for the determination of trace levels of Hg in animal tissues (muscle and kidneys) by DMA. The performance characteristics of the method development and validated indicate its fitness for use in food control.