Table 1. Variation in arsenic exposure and mortality for selected characteristics of childhood participants.
| Average As in well water (µg/L) | Baseline As in well water (µg/L) | Baseline Cohort (n = 58406) | Death (n = 185) | Rate * | |||||
| Mean | SD | Mean | SD | N | % | N | % | ||
| Sex | (χ2 = 0.2,1 P = 0.64) | ||||||||
| Male | 177.66 | 152.27 | 119.08 | 172.88 | 28756 | 49.23 | 88 | 47.57 | 4.68 |
| Female | 178.10 | 147.65 | 114.57 | 168.69 | 29650 | 50.77 | 97 | 52.43 | 5.03 |
| Age in years | (χ2 = 4.8, P = 0.017) | ||||||||
| 5–11 | 175.42 | 153.92 | 117.81 | 169.91 | 27730 | 47.48 | 73 | 39.46 | 3.67 |
| 12–18 | 180.12 | 146.22 | 115.86 | 171.56 | 30676 | 52.52 | 112 | 60.54 | 6.15 |
| Education category | (χ2 = 209.0, P = 0.000) | ||||||||
| 0 | 167.06 | 150.40 | 118.39 | 179.10 | 7970 | 13.65 | 92 | 49.73 | 20.28 |
| 1–5 | 178.78 | 150.87 | 118.65 | 170.38 | 31102 | 53.25 | 68 | 36.76 | 3.21 |
| 6+ | 180.90 | 148.04 | 113.14 | 167.84 | 19334 | 33.10 | 25 | 13.51 | 2.02 |
| SES | (χ2 = 16.2, P = 0.003) | ||||||||
| 1 poorest) | 167.59 | 149.95 | 121.54 | 181.75 | 10014 | 17.15 | 45 | 24.32 | 6.97 |
| 2 (poor) | 175.01 | 150.77 | 118.54 | 169.29 | 11655 | 19.96 | 42 | 22.70 | 5.52 |
| 3 | 180.71 | 151.11 | 120.50 | 170.52 | 13312 | 22.79 | 48 | 25.95 | 5.72 |
| 4 (rich) | 189.54 | 151.11 | 118.15 | 168.52 | 12510 | 21.42 | 22 | 11.89 | 2.63 |
| 5 (richest) | 173.60 | 145.26 | 104.48 | 164.20 | 10915 | 18.69 | 28 | 15.14 | 3.84 |
| Baseline arsenic exposure in well water | (χ2 = 5.9, P = 0.20) | ||||||||
| <10 | 123.98 | 133.87 | 1.42 | 2.04 | 28901 | 49.48 | 83 | 44.86 | 4.39 |
| 10–49 | 128.09 | 131.75 | 24.84 | 11.13 | 5092 | 8.72 | 15 | 8.11 | 4.47 |
| 50–149 | 148.26 | 93.18 | 99.91 | 29.52 | 5634 | 9.65 | 13 | 7.03 | 3.52 |
| 150–299 | 216.77 | 81.93 | 222.10 | 41.58 | 10329 | 17.68 | 39 | 21.08 | 5.77 |
| 300+ | 364.49 | 144.79 | 449.34 | 154.44 | 8450 | 14.47 | 35 | 18.92 | 6.48 |
| Time-weighted lifetime average arsenic exposure | (χ2 = 3.8, P = 0.43) | ||||||||
| <10 | 1.46 | 2.41 | 2.44 | 11.03 | 8527 | 14.60 | 24 | 12.97 | 4.21 |
| 10–49 | 28.93 | 12.04 | 21.27 | 56.38 | 5648 | 9.67 | 17 | 9.19 | 4.61 |
| 50–149 | 101.08 | 29.61 | 59.73 | 91.45 | 13357 | 22.87 | 44 | 23.78 | 5.03 |
| 150–299 | 216.80 | 41.73 | 142.85 | 139.98 | 19946 | 34.15 | 56 | 30.27 | 4.33 |
| 300+ | 415.38 | 117.02 | 277.56 | 249.35 | 10928 | 18.71 | 44 | 23.78 | 6.27 |
| Cumulative arsenic exposure | (χ2 = 6.46, P = 0.04) | ||||||||
| <1000 | 30.60 | 35.92 | 19.60 | 53.92 | 19274 | 33.00 | 54 | 29.19 | 4.16 |
| 1000–40000 | 201.55 | 82.80 | 132.41 | 145.86 | 29558 | 50.61 | 88 | 47.57 | 4.53 |
| >4000 | 401.34 | 134.37 | 264.23 | 254.73 | 9574 | 16.39 | 43 | 23.24 | 7.54 |
Crude death rate per 10000 person-years.