Table 1.
Physicochemical parameters and water quality index (WQI) of the water sampled at the Reconquista river.
| Parameters | Units | Methodology | Reconquista River water | Argentine Guidelinesa (mg/L) |
|---|---|---|---|---|
| Temperature | °C | 11.5 | ≤ 45 | |
| pH | UpH | Hanna field meter | 7.9 ± 0.1 (3) | 6.5–10 |
| Conductivity | µS/cm | Hach field meter | 720 ± 5 (3) | |
| Turbidity | UNF | 94 ± 2 (3) | ||
| Hardness | mg CaCO3/L | EDTA titration | 65 ± 5 (3) | |
| Alkalinity | mg CaCO3/L | H2SO4 titration | 678.6 ± 5.8 (3) | |
| Chlorides | mg Cl−/L | AgNO3 titration | 27 ± 1 (3) | |
| DO | mg O2/L | Iodometric | 3.4 ± 0.1 (3) | |
| Ammonium | mg N-NH4+/L | Colorimetry | 0.41 ± 0,03 (3) | 0.05–0.47 |
| Nitrites | mg N-NO2−/L | Colorimetry | 0.05 ± 0.01 (3) | ≤ 0.06 |
| PRS | mg P-PO43-/L | Colorimetry | 0.29± 0.004 (3) | |
| BOD5 | mg O2/L | Iodometric | 1.93 | ≤ 50 |
| COD | mg O2/L | Colorimetry | 18 | ≤ 250 |
| COD/BOD5 | 9.33 | |||
| WQI | 7.33 | |||
| Heavy metal | mg/L | Atomic absorption spectrophotometry | ||
| Cr | < 0.005 | 0.002 | ||
| Pb | < 0.010 | 0.001 | ||
| Cd | < 0.005 | 0.0001–0.0004 | ||
| Cu | 0.010 | 0.002–0.004 | ||
| Zn | 0.013 | ≤ 0.030 | ||
| As | 0.009 | ≤ 0.03 |
aArgentine Surface Water Guidelines for protection of aquatic life or maximum allowable content in effluents disposed in a water body. Data are expressed as mean ± SEM of three readings.