## 3 Results and Discussion  
### Metal Analysis  
Figure 2a,b show the findings of the Cd, Cu, Zn, and Pb determinations in the gills and hepatopancreta of _P. segnis_. The studies confirmed the presence of these elements in the tissues of the target crab at heterogeneous levels. The Zn levels were higher at both study locations (Table 1). According to the findings, the heavy metal levels at the two research locations and in the two tissues (the gills and hepatopancreas) followed a concentration scale in the following decreasing order: Zn > Cd > Cu > Pb (Figure 2a,b). Statistical analyses tests for the levels of the four trace elements at the Ghannouch site revealed statistically significant differences in the _P. segnis_ gills (F = 42.68; \(p\) < 0.01) and hepatopancreas (F = 42.68; \(p\) < 0.01) and in the hepatopancreas (F = 72.57; \(p\) < 0.01). In addition, the Zn, Cd, Cu and Pb contents at the Djerba site showed statistically significant differences for the gills (F = 20.31; \(p\) < 0.01) and hepatopancreas (F = 15.12; \(p\) < 0.01) (Table 1). Figure 3a reveals that the highest concentrations in the gills were found in the individuals collected from Ghannouch, near the industrial zone of Gabes, for the four studied metals, Cd (19.21 \(\pm\) 0.1 \(\upmu\)g/g), Cu (12.53 \(\pm\) 0.078 \(\upmu\)g/g), Pb (10.15 \(\pm\) 1.38 \(\upmu\)g/g), and Zn (37.36 \(\pm\) 12.57 \(\upmu\)g/g) compared to the values noted in the individuals coming from Djerba, which were Cd (7.2 \(\pm\) 0.049 \(\upmu\)g/g), Cu (6.458 \(\pm\) 0.122 \(\upmu\)g/g), Pb (2.212 \(\pm\) 0.054 \(\upmu\)g/g), and Zn (10.722 \(\pm\) 2.9 \(\upmu\)g/g). For the values obtained from the hepatopancreas, the individuals from the Ghannouch site also presented the highest levels (Figure 3b) of metallic trace elements, Cd (7.74 \(\pm\) 0.14 \(\upmu\)g/g), Cu (6.96 \(\pm\) 0.79 \(\upmu\)g/g), Pb (4.536 \(\pm\) 0.24 \(\upmu\)g/g), and Zn (18.14 \(\pm\) 8.38 \(\upmu\)g/g), in comparison with the contents in the tissues of the individuals from Djerba, Cd (3.18 \(\pm\) 0.04 \(\upmu\)g/g), Cu (2.91 \(\pm\) 0.087 \(\upmu\)g/g), Pb (2.212 \(\pm\) 0.054 \(\upmu\)g/g), and Zn (8.71 \(\pm\) 1.03 \(\upmu\)g/g). In fact, the statistical analyses between the two study stations showed \begin{table}
\begin{tabular}{l l l l l l l} \hline \hline
**Site** & **Tissues** & **Element** & **Mean \(\pm\) SD** & **F** & \(\mathbf{p}\) \\ \hline \multirow{8}{*}{**Ghannouch**} & & Cd & 19.21 \(\pm\) 0.1 & & \\  & & Cu & 12.53 \(\pm\) 0.078 & & \\  & & Pb & 10.15 \(\pm\) 1.38 & & \\  & & Zn & 37.36 \(\pm\) 12.57 & & \\ \cline{2-6}  & & & Cd & 7.74 \(\pm\) 0.14 & & \\  & & Cu & 6.96 \(\pm\) 0.79 & \\  & & Pb & 4.536 \(\pm\) 0.24 & \\  & & Zn & 18.14 \(\pm\) 8.38 & & \\ \hline \multirow{8}{*}{**Djerba**} & & Cd & 7.2 \(\pm\) 0.049 & & \\  & & Cu & 6.45 \(\pm\) 0.12 & & \\ \cline{1-1}  & & Pb & 4.9 \(\pm\) 0.01 & & \\ \cline{1-1}  & & Zn & 10.72 \(\pm\) 2.9 & & \\ \cline{1-1} \cline{2-6}  & & & Cd & 3.18 \(\pm\) 0.04 & & \\ \cline{1-1}  & & Cu & 2.91 \(\pm\) 0.08 & & \\ \cline{1-1}  & & Pb & 2.21 \(\pm\) 0.05 & & \\ \cline{1-1}  & & Zn & 8.71 \(\pm\) 1.03 & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Metal data (mg/kg dw) in _P. segnis_ at the two studied sites for the gills and hepatopancreas. statistically significant differences in gill levels for Cd (F = 23.32; \(p<0.01\)), Cu (F = 92.35; \(p<0.01\)), Zn (F = 62.24; \(p<0.01\)), and Pb (F = 23.96; \(p<0.01\)), as well as for the levels in the hepatopancreas for Cd (F = 74.39; \(p<0.01\)), Cu (F = 17.11; \(p<0.01\)), Zn (F = 54.31; \(p<0.01\)), and Pb (F = 36.06; \(p<0.01\)) (Figure 3a,b). Only Italy [29] and Turkey [30; 31] have provided data on metal levels in Mediterranean _Portuus segtis_ populations. With a few exceptions, the majority of these research analyses were performed solely on soft tissues.