Table 2.
Average (±SE) proportion of microcystin structural variants and microcystin concentrations (in MC-LR equiv.) recorded at Kisumu Bay from various sample types (n = 4).
| Structural Variant | Retention (min) | Surface | Integrated | Patch | Shore | p-Value 1 |
|---|---|---|---|---|---|---|
| Proportion | ||||||
| MC-YR | 17.06–17.26 | 40 ± 5 a,b | 26 ± 6 b | 45 ± 2 a | 33 ± 4 a,b | 0.015 |
| MC-LR | 18.34–18.52 | 28 ± 4 | 18 ± 4 | 29 ± 2 | 26 ± 4 | 0.136 |
| MC m/z 1052 | 23.95–24.16 | 25 ± 9 | 51 ± 12 | 16 ± 1 | 31 ± 9 | 0.05 |
| MC m/z 1002 | 25.0–25.07 | 7 ± 3 | 6 ± 2 | 11 ± 2 | 9 ± 2 | 0.463 |
| Concentration (µg/L) | ||||||
| MC-YR | 17.06–17.26 | 0.6 ± 0.4 a,b | 0.5 ± 0.1 b | 343 ± 186 a | 29 ± 17 a,b | <0.001 |
| MC-LR | 18.34–18.52 | 1.3 ± 0.3 b | 0.4 ± 0.1 b | 210 ± 102 a | 22 ± 12 a,b | <0.001 |
| MC m/z 1052 | 23.95–24.16 | 1.4 ± 0.6 b | 1.2 ± 0.3 b | 160 ± 94 a | 17 ± 9 a,b | <0.001 |
| MC m/z 1002 | 25.0–25.07 | 0.6 ± 0.5 b | 0.2 ± 0.04 b | 111 ± 60 a | 9 ± 5 a,b | <0.001 |
1 Friedman Repeated Measures ANOVA on Ranks (Superscripts indicate homogeneous subsets not significantly different at p = 0.05 according to Tukey-test post-hoc pairwise comparison).