Table 1.
Observed and Expected Numbers of Deaths and Standardized Mortality Ratios for Cancer According to Age at Potential First Exposure to High Levels of Arsenic in Drinking Water, Antofagastaa, Chile, 2001–2010
| Disease and Age at First Exposure, years | Total | Men | Women | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Obs | Exp | SMR | 95% CI | P Valueb | Obs | Exp | SMR | 95% CI | P Value | Obs | Exp | SMR | 95% CI | P Value | |
| Lung cancer | |||||||||||||||
| Birth | 57 | 15.1 | 3.8 | 2.9, 4.9 | <0.001 | 27 | 9.3 | 2.9 | 1.9, 4.2 | <0.001 | 30 | 5.9 | 5.1 | 3.4, 7.3 | <0.001 |
| 1–10 | 237 | 52.4 | 4.5 | 4.0, 5.1 | <0.001 | 178 | 35.8 | 5.0 | 4.3, 5.8 | <0.001 | 59 | 17.4 | 3.4 | 2.6, 4.4 | <0.001 |
| 11–20 | 417 | 101.6 | 4.1 | 3.7, 4.5 | <0.001 | 328 | 69.2 | 4.7 | 4.2, 5.3 | <0.001 | 89 | 32.9 | 2.7 | 2.2, 3.3 | <0.001 |
| 21–30 | 457 | 122.1 | 3.7 | 3.4, 4.1 | <0.001 | 322 | 77.7 | 4.1 | 3.7, 4.6 | <0.001 | 135 | 43.1 | 3.1 | 2.6, 3.7 | <0.001 |
| 31–40 | 176 | 62.6 | 2.8 | 2.4, 3.3 | <0.001 | 112 | 33.8 | 3.3 | 2.7, 4.0 | <0.001 | 64 | 27.6 | 2.3 | 1.8, 3.0 | <0.001 |
| ≥41 | 28 | 13.6 | 2.1 | 1.4, 3.0 | <0.001 | 9 | 5.6 | 1.6 | 0.7, 3.0 | 0.12 | 19 | 7.1 | 2.7 | 1.6, 4.2 | <0.001 |
| P for trendc | <0.001 | 0.001 | 0.006 | ||||||||||||
| Bladder cancer | |||||||||||||||
| Birth | 24 | 1.5 | 16.0 | 10.3, 23.8 | <0.001 | 17 | 1.0 | 16.8 | 9.8, 27.0 | <0.001 | 7 | 0.5 | 13.6 | 5.5, 27.9 | <0.001 |
| 1–10 | 35 | 4.8 | 7.4 | 5.1, 10.3 | <0.001 | 28 | 3.5 | 7.9 | 5.3, 11.5 | <0.001 | 7 | 1.3 | 5.3 | 2.2, 11.0 | <0.001 |
| 11–20 | 59 | 9.3 | 6.3 | 4.8, 8.1 | <0.001 | 32 | 6.7 | 4.8 | 3.3, 6.8 | <0.001 | 27 | 2.7 | 9.9 | 6.5, 14.5 | <0.001 |
| 21–30 | 112 | 16.6 | 6.7 | 5.5, 8.1 | <0.001 | 65 | 11.1 | 5.9 | 4.5, 7.5 | <0.001 | 47 | 5.3 | 8.8 | 6.5, 11.7 | <0.001 |
| 31–40 | 80 | 15.6 | 5.1 | 4.1, 6.4 | <0.001 | 39 | 8.8 | 4.4 | 3.1, 6.0 | <0.001 | 41 | 6.4 | 6.4 | 4.6, 8.7 | <0.001 |
| ≥41 | 22 | 5.3 | 4.2 | 2.6, 6.3 | <0.001 | 13 | 2.6 | 4.9 | 2.6, 8.4 | <0.001 | 9 | 2.5 | 3.6 | 1.6, 6.8 | 0.001 |
| P for trend | <0.001 | <0.001 | 0.01 | ||||||||||||
| Kidney cancer | |||||||||||||||
| Birth | 8 | 6.2 | 1.3 | 0.6, 2.5 | 0.28 | 4 | 4.5 | 0.9 | 0.2, 2.3 | 0.50 | 4 | 1.8 | 2.2 | 0.6, 5.6 | 0.11 |
| 1–10 | 25 | 14.4 | 1.7 | 1.1, 2.6 | 0.007 | 18 | 10.8 | 1.7 | 1.0, 2.6 | 0.03 | 7 | 3.9 | 1.8 | 0.7, 3.7 | 0.10 |
| 11–20 | 49 | 21.5 | 2.3 | 1.7, 3.0 | <0.001 | 32 | 15.3 | 2.1 | 1.4, 3.0 | <0.001 | 17 | 6.4 | 2.6 | 1.5, 4.2 | <0.001 |
| 21–30 | 46 | 26.1 | 1.8 | 1.3, 2.4 | <0.001 | 29 | 16.7 | 1.7 | 1.2, 2.5 | 0.009 | 17 | 9.0 | 1.9 | 1.1, 3.0 | 0.01 |
| 31–40 | 38 | 14.1 | 2.7 | 1.9, 3.7 | <0.001 | 16 | 7.4 | 2.2 | 1.2, 3.5 | 0.004 | 22 | 6.5 | 3.4 | 2.1, 5.1 | <0.001 |
| ≥41 | 7 | 3.4 | 2.0 | 0.8, 4.2 | 0.06 | 3 | 1.5 | 2.0 | 0.4, 5.9 | 0.19 | 4 | 1.9 | 2.1 | 0.6, 5.4 | 0.12 |
| P for trend | 0.12 | 0.24 | 0.39 | ||||||||||||
| Laryngeal cancer | |||||||||||||||
| Birth | 5 | 0.7 | 6.8 | 2.2, 15.8 | 0.001 | 3 | 0.6 | 4.8 | 1.0, 14.1 | 0.03 | 2 | 0.1 | 14.4 | 1.3, 51.9 | 0.009 |
| 1–10 | 6 | 2.6 | 2.3 | 0.8, 4.9 | 0.05 | 5 | 2.4 | 2.1 | 0.7, 4.8 | 0.10 | 1 | 0.3 | 3.3 | 0.1, 18.3 | 0.26 |
| 11–20 | 17 | 5.3 | 3.2 | 1.9, 5.1 | <0.001 | 15 | 4.8 | 3.1 | 1.7, 5.1 | <0.001 | 2 | 0.5 | 3.7 | 0.4, 13.2 | 0.10 |
| 21–30 | 12 | 7.6 | 1.6 | 0.8, 2.7 | 0.09 | 10 | 6.5 | 1.5 | 0.7, 2.8 | 0.12 | 2 | 1.0 | 2.1 | 0.3, 7.5 | 0.25 |
| 31–40 | 8 | 3.9 | 2.1 | 0.9, 4.1 | 0.04 | 6 | 3.0 | 2.0 | 0.7, 4.3 | 0.09 | 2 | 0.7 | 2.9 | 0.4, 10.6 | 0.15 |
| ≥41 | 1 | 0.8 | 1.3 | 0.1, 7.1 | 0.50 | 1 | 0.5 | 1.9 | 0.1, 10.3 | 0.42 | 0 | 0.2 | 0 | ||
| P for trend | 0.03 | 0.18 | 0.06 | ||||||||||||
| All cancers | |||||||||||||||
| Birth | 94 | 23.5 | 4.0 | 3.2, 4.9 | <0.001 | 51 | 15.5 | 3.3 | 2.4, 4.3 | <0.001 | 43 | 8.4 | 5.1 | 3.7, 6.9 | <0.001 |
| 1–10 | 303 | 74.2 | 4.1 | 3.6, 4.6 | <0.001 | 229 | 52.5 | 4.4 | 3.8, 5.0 | <0.001 | 74 | 22.9 | 3.2 | 2.5, 4.1 | <0.001 |
| 11–20 | 542 | 137.8 | 3.9 | 3.6, 4.3 | <0.001 | 407 | 95.9 | 4.2 | 3.8, 4.7 | <0.001 | 135 | 42.6 | 3.2 | 2.7, 3.8 | <0.001 |
| 21–30 | 627 | 172.5 | 3.6 | 3.4, 3.9 | <0.001 | 426 | 112.0 | 3.8 | 3.4, 4.2 | <0.001 | 201 | 58.4 | 3.4 | 3.0, 4.0 | <0.001 |
| 31–40 | 302 | 96.1 | 3.1 | 2.8, 3.5 | <0.001 | 173 | 53.1 | 3.3 | 2.8, 3.8 | <0.001 | 129 | 41.2 | 3.1 | 2.6, 3.7 | <0.001 |
| ≥41 | 58 | 23.0 | 2.5 | 1.9, 3.3 | <0.001 | 26 | 10.9 | 2.4 | 1.6, 3.5 | <0.001 | 32 | 11.7 | 2.7 | 1.9, 3.9 | <0.001 |
| P for trend | <0.001 | 0.002 | 0.06 | ||||||||||||
| All other cancers | |||||||||||||||
| Birth | 278 | 238.8 | 1.2 | 1.0, 1.3 | 0.007 | 133 | 97.3 | 1.4 | 1.1, 1.6 | <0.001 | 145 | 138.2 | 1.0 | 0.9, 1.2 | 0.29 |
| 1–10 | 454 | 389.2 | 1.2 | 1.1, 1.3 | <0.001 | 239 | 170.0 | 1.4 | 1.2, 1.6 | <0.001 | 215 | 216.9 | 1.0 | 0.9, 1.1 | 0.53 |
| 11–20 | 652 | 614.7 | 1.1 | 1.0, 1.1 | 0.07 | 353 | 308.8 | 1.1 | 1.0, 1.3 | 0.007 | 299 | 305.7 | 1.0 | 0.9, 1.1 | 0.64 |
| 21–30 | 833 | 803.2 | 1.0 | 1.0, 1.1 | 0.15 | 453 | 420.0 | 1.1 | 1.0, 1.2 | 0.06 | 380 | 378.5 | 1.0 | 0.9, 1.1 | 0.48 |
| 31–40 | 604 | 582.6 | 1.0 | 1.0, 1.1 | 0.19 | 305 | 274.9 | 1.1 | 1.0, 1.3 | 0.04 | 299 | 301.0 | 1.0 | 0.9, 1.1 | 0.53 |
| ≥41 | 166 | 189.5 | 0.9 | 0.7, 1.0 | 0.95 | 68 | 75.7 | 0.9 | 0.7, 1.1 | 98 | 112.3 | 0.9 | 0.7, 1.1 | 0.91 | |
| P for trend | 0.001 | <0.001 | 0.37 | ||||||||||||
Abbreviations: CI, confidence interval; Exp, expected number; Obs, observed number; SMR, standardized mortality ratio.
a All data presented for Antofagasta include neighboring Mejillones, which had the same water sources.
b One-sided P value for mortality being increased in Antofagasta as compared with the rest of Chile.
c Two-sided P value for linear trend in the SMRs for each 10-year increase in age at first exposure in Antofagasta.