Table 1.
Characteristics of the study population by country and self-described ethnicity.
| Total Population | Arizona, USA Non-Hispanic |
Arizona, USA Hispanic |
Sonora, Mexico Hispanic |
P-value† | |
|---|---|---|---|---|---|
| Number of participants (n, %) | 377 | 165 (43.8) | 50 (13.3) | 162 (43.0) | |
| Gender (n, %) | |||||
| Male | 133 (35.2) | 68 (41.2) | 23 (46.0) | 42 (25.8) | |
| Female | 245 (64.8) | 97 (58.8) | 27 (54.0) | 121 (74.2) | 0.007 |
| Age in years (mean, SD) | 50.0 ± 16.3 | 57.2 ± 14.7 | 48.9 ± 15.5 | 43.0 ± 14.9 | <0.001 |
| BMI (mean, SD) | 28.8 ± 5.9 | 28.1 ± 5.9 | 31.6 ± 6.5 | 28.8 ± 5.5 | 0.001 |
| Current smoker | 64 (18.3) | 27 (17.6) | 3 (7.0) | 34 (22.2) | 0.120 |
| Frequent alcohol use (> 4x/wk) | 37 (7.6) | 32 (18.5) | 5 (9.6) | 0 (0) | <0.001 |
| Physician-diagnosed diabetes | 40 (10.6) | 20 (12.2) | 11 (22.0) | 9 (5.8) | 0.017 |
| Drinking water As, geometric mean (95% CI) | |||||
| Weighted concentration# (μg/L) | 7.65 (6.80-8.63) | 8.66 (6.93-10.81) | 4.56 (3.77-5.51) | 7.91 (6.90-9.07) | <0.002 |
| Total volume consumed (L/day) | 0.63 (0.55-0.72) | 1.37 (1.20-1.58) | 1.03 (0.48-1.37) | 0.24 (0.20-0.29) | <0.001 |
| Drinking water intake (μg/day) | 2.47 (1.99-3.07) | 5.83 (4.23-8.02) | 3.37 (2.37-4.80) | 0.93 (0.68-1.28) | <0.001 |
| Urinary arsenic, adjusted for specific gravity (μg/L), geometric mean (95% CI) | |||||
| Total | 41.19 (37.65-45.07) | 33.57 (28.92-38.98) | 24.86 (21.81-28.33) | 59.17 (52.63-66.51) | <0.001 |
| As+3 | 1.10 (0.98-1. 23) | 0.72 (0.60-0.85) | 0.54 (0.42-0.69) | 2.10 (1.86-2.37) | <0.001 |
| As+5 | 0.82 (0.71-0.93) | 0.61 (0.49-0.76) | 0.47 (0.34-0.65) | 1.29 (1.08-1.55) | <0.001 |
| MMA | 2.04 (1.85-2.25) | 1.66 (1.40-1.96) | 1.06 (0.87-1.30) | 3.06 (2.75-3.41) | <0.001 |
| DMA | 13.67 (12.50-14.95) | 10.38 (8.93-12.06) | 7.89 (6.67-9.35) | 21.39 (19.44-23.52) | <0.001 |
| Sum of species | 18.44 (18.86-20.17) | 13.99 (12.01-16.28) | 10.60 (9.05-12.43) | 28.91 (26.31-31.77) | <0.001 |
| Urine specific gravity, geometric mean (95% CI) | |||||
| 1.016 (1.015-1.017) | 1.015 (1.015-1.017) | 1.015 (1.014-1.017) | 1.017 (1.016-1.018) | 0.035 | |
| Serum MMP-9 (ng/mL), geometric mean (95% CI) | |||||
| 295.60 (274.4-318.5) | 347.4 (311.6-387.3) | 250.0 (204.1-306.3) | 264.2 (235.4-296.5) | <0.001 | |
†
P-values based on chi-square test, analysis of variance, or Kruskal-Wallis test
#
Weighted concentration = (where n = the number of drinking sources used by the individual, and frequencyi =the frequency of use of each source i).