Table 3 Heavy metal concentrations in the constructed wetlands before and after treatments
Samples | Cr (mg/L) | Cu (mg/L) | Zn (mg/L) | Cd (mg/L) | Ni (mg/L) | Fe (mg/L) | Pb (mg/L) |
|---|---|---|---|---|---|---|---|
Influent | 0.61 ± 0.08 | 0.73 ± 0.11 | 0.58 ± 0.03 | 0.046 ± 0.02 | 0.278 ± 0.6 | 3.23 ± 0.6 | 0.3 ± 0.03 |
Typha domingensis | 0.13 ± 0.01 | 0.11 ± 0.05 | 0.07 ± 0.01 | 0.004 ± 0.034 | 0.015 ± 0.08 | 1.04 ± 0.01 | 0.05 ± 0.03 |
Cyperus papyrus | 0.07 ± 0.05 | 0.086 ± 0.03 | 0.05 ± 0.006 | 0.007 ± 0.001 | 0.047 ± 0.06 | 0.8 ± 0.06 | 0.06 ± 0.02 |
Control | 0.42 ± 0.14 | 0.5 ± 0.14 | 0.32 ± 0.12 | 0.033 ± 0.023 | 0.184 ± 0.3 | 1.23 ± 0.014 | 0.18 ± 0.07 |
WHO guideline | 0.05 | 1.00 | 3.00 | 0.003 | 0.20 | 0.10 | 0.01 |