Table 1.
Descriptive statistics for the DVWA concentrations of urinary metabolites for selected OP pesticides in the three study phases.
| Study phase | No. | Frequency of detection (%) | Median (μg/L) | Mean ± SD (μg/L) | Maximum (μg/L) |
|---|---|---|---|---|---|
| MDA (LOD = 0.3 μg/L) | |||||
| 1 | 87 | 60 | 1.5 | 2.9 ± 5.0* | 96.5 |
| 2 | 116 | 22 | 0 | 0.3 ± 0.9* | 7.4 |
| 3 | 156 | 60 | 1.6 | 4.4 ± 12.4* | 263.1 |
| TCPY (LOD = 0.2 μg/L) | |||||
| 1 | 87 | 78 | 6.0 | 7.2 ± 5.8** | 31.1 |
| 2 | 116 | 50 | 0.9 | 1.7 ± 2.7** | 17.1 |
| 3 | 155 | 78 | 4.3 | 5.8 ± 5.4** | 25.3 |
| IMPY (LOD = 0.7 μg/L) | |||||
| 1 | 71 | 14 | 0 | < LOD ± 0.2 | 1.2 |
| 2 | 107 | 9 | 0 | < LOD ± 0.1 | 0.4 |
| 3 | 148 | 14 | 0 | < LOD ± 1.3 | 14.6 |
| DEAMPY (LOD = 0.2 μg/L) | |||||
| 1 | 70 | 25 | 0 | 0.37 ± 2.2 | 17.4 |
| 2 | 103 | 25 | 0 | < LOD ± 0.1 | 0.8 |
| 3 | 146 | 25 | 0 | < LOD ± 0.3 | 2.3 |
| CMHC (LOD = 0.2 μg/L) | |||||
| 1 | 87 | 25 | 0 | < LOD ± 0.03 | 0.2 |
| 2 | 115 | 25 | 0 | < LOD ± 0.03 | 0.2 |
| 3 | 156 | 25 | 0 | < LOD ± 0.04 | 0.2 |
Abbreviations: CMHC, 3-chloro-4-methyl-7-hydroxycoumarin; DEAMPY, 2-diethylamino-6-methylpyrimidin-4-ol; IMPY, 2-isopropyl-6-methyl-pyrimidin-4-ol; MDA, malathion dicarboxylic acid; TCPY, 3,5,6-trichloro-2-pyridinol.
*Significantly different (one-way ANOVA, p < 0.01; Tukey test, phase 2 level significantly lower than levels in phase 1 and 3).
**Significantly different (one-way ANOVA, p < 0.001; Tukey test, phase 2 level significantly lower than phase 1 and 3 levels).