Extractant property | Extractant | ||
Deionized water | Rainwater | Groundwater | |
Electrical conductivity (µS∙cm−1) | 0.9 (<0.01)aa | 4.1 (<0.01)b | 296 (0.6)c |
pH | 8.22 (0.01)a | 5.24 (0.02)b | 7.64 (0.02)c |
Arsenic (mg∙L−1) | <0.005b | <0.005b | <0.005b |
Chromium (mg∙L−1) | <0.001b | <0.001b | <0.001b |
Selenium (mg∙L−1) | <0.005b | <0.005b | <0.005b |