## 3 Results
### Mineral and Metal Contents in Plant Organs and Fruit Parts  
Plants receiving wastewater irrigation accumulated high mineral contents in their parts as compared to the plants irrigated with canal water. Of the edible parts of wastewater-irrigated plants, the mesocarp accumulated a high amount of Na, with a 19% increase over control, while among the nonedible parts, the root accumulated a maximum amount of Na, \begin{table}
\begin{tabular}{c c c c c c c c} \hline
**Attribute** & **Water** & \multicolumn{2}{c}{**Permissible Limit in Water (mg L\({}^{-1}\))**} & \multicolumn{2}{c}{**Soil**} & \multicolumn{2}{c}{**Permissible Limits in Soil (mg kg\({}^{-1}\))**} \\ \cline{2-9}  & **(mg L\({}^{-1}\))** & **a** & **b** & **c** & **(mg kg\({}^{-1}\))** & **d** & **e** & **f** \\ \hline EC (dS m\({}^{-1}\)) & 2.5 & 0.7 & 1.5 & n.a. & 1.9 & n.a. & n.a. & n.a. \\ pH & 7.11 & 6.5-8.4 & 6.5-8.4 & n.a. & 7.41 & n.a. & n.a. & n.a. \\ Co & 0.00 & - & - & - & ND & - & - & - \\ Cd & 0.00 & - & - & - & ND & - & - & - \\ Mn & 0.16 & 0.20 & n.a. & 0.05 & 19.00 & n.a. & n.a. & n.a. \\ Cu & 0.10 & - & - & - & ND & - & - & - \\ Ni & 0.05 & - & - & - & ND & - & - & - \\ Fe & 0.46 & 5.0 & 5.0 & 1.0 & 35.88 & n.a. & n.a. & n.a. \\ Zn & 0.77 & 2.0 & 2.0 & 1.0 & 28.84 & 80.0 & 150–300 & 300–600 \\ Pb & 0.44 & 5.0 & 0.1 & 0.05 & 29.62 & 50.0 & 300–600 & 250–500 \\ \hline \end{tabular} ND = not determined due to very low concentration in wastewater; n.a. = not reported by the agency. a FAO [27]; b [28]; c [29]; d [30]; e [31]; f Indian standards [32; 33].  
\end{table} 
Table 1: Heavy metals in wastewater and soil and their comparison with standards set by various organizations/researchers. Figure 1: Concentrations of different metals and mineral nutrients in wastewater (**a,c**) and soil being irrigated with wastewater (**b,d**); *, **, *** = significant at 0.05, 0.01, and 0.001 levels, respectively; ns = nonsignificant. with a 42% increase over control. In contrast, no significant differences were found in stem and leaf Na contents, where a 34% increase in Na over control was recorded. The order of decreasing Na concentration in wastewater-grown plant organs was: mesocarp > root > pericarp > endocarp > stem > leaves (Figure 2a). The comparison of K accumulation in different plant organs showed that the stem (nonedible part) had a high accumulation of K, followed by the endocarp (edible part), and they showed an increase of 20% and 38% compared with that in the organs of plants irrigated with canal water. Leaves and the mesocarp accumulated an equal amount of K.  
Figure 2: Concentrations of Na (**a**), K (**b**), and Ca (**c**) in different organs of tomato plants and fruits grown with wastewater; **, ***, *** = significant at 0.05, 0.01, and 0.001 levels, respectively; ns = nonsignificant. The decreasing order of K concentration in edible and nonedible parts of plants grown with wastewater was stem > endocarp > mesocarp > leaves > root > pericarp (Figure 2b). Wastewater-irrigated plants accumulated a higher amount of Ca than plants irrigated with canal water. By comparing its accumulation in different plant organs, it was found that leaves accumulated higher Ca content, followed by stems, with 39% and 31% increases compared with plants grown with canal water irrigation. The minimum accumulation of Ca was found in the endocarp, which differed nonsignificantly from the control. The decreasing order of Ca concentration in wastewater-irrigated plants was leaves > stem > root > pericarp > mesocarp > endocarp (Figure 2c). The plants irrigated with wastewater had higher N content than canal-water-irrigated plants, in all their parts. The maximum N content was found in leaves, followed by the endocarp, while no significant difference was found in leaf N content compared with control plants. On the other hand, N was found in almost equal amounts in the stem and mesocarp. N concentration in different organs of wastewater-grown plants was in the following decreasing order: leaves > endocarp > root > mesocarp > pericarp > stem (Figure 3a).