The aim of this paper was to evaluate the cadmium concentrations in the muscles, liver, and kidney of three age categories (≤ 8 months; ≤ 2 years; ≥ 2 years) of cattle during the period of years 2014–2019 and to determine the age limit at which the concentration of cadmium in an organ with the highest accumulation increases health risk for consumers. In cattle above two years of age, there was a higher average cadmium concentration in the liver (0.10 mg/kg) and kidney (0.62 mg/kg), when compared with cadmium concentration in the liver (0.06 mg/kg) and kidney (0.24 mg/kg) of cattle under two years of age. A paired correlation coefficient r = 0.825 8 (P < 0.006) and Spearman’s coefficient ρ = 0.92 (P < 0.000 1) were calculated for the dependence of the cadmium concentration on the age. The correlation analysis statistically demonstrated a significant positive correlation between the concentration of cadmium in the kidney and the age of the cattle. A non-significant difference between the maximum limit and the average concentration of the cadmium in the kidney of the cattle from the age of 6 years (P = 0.029) was demonstrated using the t-test. The cadmium concentration in the muscles was low and was not significantly affected by the cattle’s age.
The assessment of mercury content in the muscle, liver and kidneys of fattening pigs and sows was conducted in the Czech Republic during the period of 2015–2019. The samples were collected from sows (n = 31) and fattening pigs (n = 210). The average mercury content in muscle, liver, and kidneys of sows over 5 years was 0.00057 ± 0.00004, 0.0045 ± 0.0008, and 0.0224 ± 0.0067 mg·kg-1, respectively. The average mercury content in muscle, liver, and kidneys of fattening pigs over the same period was 0.00059 ± 0.00004, 0.0012 ± 0.0001, and 0.0044 ± 0.0004 mg·kg-1, respectively. The maximum residual limit (MRL) for human consumption was exceeded in 14 kidney samples. The mercury content in liver did not differ significantly between sows and fattening pigs; in kidneys, the mercury content was higher in sows, with a significant difference in one year (P < 0.05). A slight decrease in the mercury content in kidneys and liver was observed in fattening pigs from the year 2015. In sows, there was a significant increase in the mercury content in kidneys in the year 2016. It can be concluded that there is a need for further monitoring of the mercury content in pig tissues in the Czech Republic.