Table 5.
Comparison of urinary concentrations of dialkylphosphates with the results of other similar studies.
| Diethylphosphate metabolitesa | Dimethylphosphate metabolites | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
|
||||||||||||||||
| No. subjects | >LODbDEP | >LODbDEPT | >LODb Sum DEAP | >LODb DMP | >LODb DMTP | >LODb DMDTP | >LODb Sum DMAP | |||||||||
| (Area) | Age | (%) | (nmol/l)c | (%) | (nmol/l)c | (%) | nmol/ld | (%) | (nmol/l)c | (%) | (nmol/l)c | (%) | (nmol/l)c | (%) | nmol/ld | |
| Current Chilean | ||||||||||||||||
| Study | ||||||||||||||||
| Dec 2010 samples | 190 | 6-11 | 40.5 | 59.3 | 43.2 | 48.9 | 72.6 | 155.8 | 20.5 | 41.3 | 25.8 | 38.8 | 16.3 | 56.0 | 31.6 | 147.7 |
| (spray month) | (Talca, Chile) | (49.1-75.5) | (41.4-57.6) | (133.4-182.0) | (36.6-46.5) | (34.5-43.7) | (51.6-60.8) | (133.3-163.6) | ||||||||
| May 2011 samples | 181 | 126.4 | 21.8 | 160.7 | 36.0 | 32.0 | 44.7 | 120.5 | ||||||||
| (nonspray month) | (Talca, Chile) | 7-12 | 80.1 | (107.1-149.2) | 2.8 | (20.9-22.7) | 80.0 | (140.1-184.4) | 14.9 | (32.9-39.4) | 13.8 | (28.8-35.6) | <LOD | (44.7-44.7) | 18.6 | (111.7-129.9) |
| Comparison studies | ||||||||||||||||
| Azaroff et al. 1999k | 136 (El Salvador, farm children) |
8-17 | -- | -- | -- | 14 | -- | -- | -- | -- | -- | -- | 35 | -- | ||
| Koch et al. 2002f(16) | 44 (Seattle) |
2-5 | - | - | 53.0 | - | 0.03(1.56)g | - | - | 73.0 | - | - | - | - | 0.080(2.51) g | |
| Barr et al. 2004 h(25) | 471 (US population) |
6-11 | - | 1.73 h (1.06-2.83) |
- | - | - | 17.4h (11.1-27-3) |
- | - | - | 3.08 h (1.9-4.9) |
- | - | - | 72.8 h (54.3-97.5) |
| Grandjean et al. 2006 k | 72 (Ecuador) |
5-9 | 82 | -- | 58 | -- | 89 | -- | 85 | -- | 17 | -- | 28 | -- | 85 | -- |
| Marks et al. 2010i, j(14) | 290 | 3.5 | - | - | - | - | - | 7.0 | - | - | - | - | - | - | - | 62.5 (52.5-74.7) |
| 320 (Salinas Valley, California) |
5 | - | - | - | - | - | 7.2 (6.0-8.7) |
- | - | - | - | - | - | - | 72.4 (61.0-86.0) |
|
| Bouchard et al. 2010i, j(15) | 1139 (US population) |
8-15 | 53.1 | 4.7 (0.9-28.1) |
57.2 | 2.0 (0.4-7.6) |
77.8 | 11.0 (2.1-35.0) |
49 | 10.7 (2.8-39.0) |
64.3 | 13.7 (1.9-58.8) |
41.7 | 1.7 (0.4-7.3) |
81.7 | 41.3 (10.1-130.7) |
DEP = diethylphosphate; DETP = diethylthiophosphate; DEAP = diethyl alkylphosphates; DMP = dimethylphosphate; DMTP =dimethyldithiophosphate; DMDTP = dimethyldithiophosphate; DMAP = dimethylalkylphosphates; LOD = limit of detection
Diethyldithiophosphate (DEDTP) are not presented in this table because its values were lower than the LOD in almost all the children.
Samples below the LOD were assigned a value of LOD/V2 (Hornung and Reed, 1990). The limit of detection was 10.0 μg/L for dimethyl dithiophosphate (DMDTP) and 5.0 μg/L for all other alkylphosphate metabolites measured.
Values correspond to geometric means and confidence interval(95%).
Diethyl and dimethyl phosphate metabolites were summed as nmol/l. Values correspond to geometric mean and confidence interval.
Double dash (−) indicates LOD % or analyte not reported.
LOD are 7.4(μg/l) for DMP, 1.1 for DMTP, 0.7 for DMDTP, 6.6 for DEP, 1.2 for DETP, and 1.1 for DEDTP.
Geometric mean and SD.
LOD were 0.58(μg/l) for DMP, 0.18(μg/l) for DMTP, 0.08 (μg/l) for DMDTP, 0.2 (μg/l) for DEP, 0.09 (μg/l) for DETP, and 0.05 (|μg/l) for DEDTP. Geometric means were adjusted for age, sex, race/ethnicity, and concentrations of serum cotinine and urinary creatinine. GMs were calculated for metabolites with detection frequencies of ≥ 60%.
Values for LOD of metabolites were not reported.
Neither of these two studies evaluating urinary DAP concentrations in Latin America reported actual urinary DAP concentrations for the populations studied; only frequencies of detection were given.