The highest nickel concentrations were reported from El-Salam and El-Marg and the lowest
from El-Mataria areas, which were 1.42 ppm, 1.42 ppm and 0.05 ppm respectively (Figure 4).
All areas have exceeded the standard limit (0.03 ppm) in all samples.
Almost all areas except El-Marg have shown the molybdenum concentration to exceed the
standard limit (0.07 ppm) which varied from 0.09 ppm to 0.43 ppm. The highest
concentrations were represented by Heliopolice and El-Salam areas (Figure 5).