Table 1. Characteristics of 985 subjects of this study.
| Parameters | Exposed groups (by distance from smelter) | Control group ≥ 15 km |
P | |||
|---|---|---|---|---|---|---|
| E1 ( | E2 (1-2 km) | E3 (2-3 km) | E4 (3-4 km) | |||
| No. of subjects | 108 | 312 | 122 | 30 | 413 | - |
| Age, yr | 63.67 ± 12.50 | 63.04 ± 11.92 | 64.63 ± 10.28 | 57.33 ± 10.76 | 65.86 ± 11.42 | < 0.001* |
| Duration of residence, yr | 40.58 ± 19.27 | 39.79 ± 21.10 | 37.64 ± 19.09 | 29.63 ± 22.55 | 43.27 ± 22.74 | 0.002† |
| Gender | 0.511‡ | |||||
| Male | 49 (45.4) | 129 (41.3) | 52 (42.6) | 15 (50.0) | 158 (38.3) | |
| With work history in smelter | 30 | 63 | 27 | 3 | 0 | |
| Without work history in smelter | 19 | 66 | 25 | 12 | 158 | |
| Female | 59 (54.6) | 183 (58.7) | 70 (57.4) | 15 (50.0) | 255 (61.7) | |
| With work history in smelter | 8 | 17 | 1 | 1 | 0 | |
| Without work history in smelter | 51 | 166 | 69 | 14 | 255 | |
| Smoking status | 0.924‡ | |||||
| Smoker§ | 21 (19.4) | 44 (14.1) | 24 (19.7) | 6 (20.0) | 50 (12.1) | |
| Non-smoker | 87 (80.6) | 268 (85.9) | 98 (80.3) | 24 (80.0) | 363 (87.9) | |
| Drinking status | 0.638‡ | |||||
| Drinker | 50 (46.3) | 168 (53.8) | 64 (52.5) | 13 (43.3) | 188 (45.5) | |
| Non-drinker | 58 (53.7) | 144 (46.2) | 58 (47.5) | 17 (56.7) | 225 (54.5) | |
| Level of toxic metals, geometric means (geometric standards deviation) | ||||||
| Urinary As (µg/g creatinine) | 8.78 (1.64) | 9.25 (1.67) | 9.41 (1.68) | 8.14 (1.51) | 8.36 (1.63) | 0.035 |
| Blood Pb, µg/dL | 4.85 (1.53) | 4.16 (1.61) | 4.11 (1.55) | 3.57 (1.70) | 3.13 (1.49) | < 0.001∥ |
| Blood Cd, µg/L | 3.62 (1.86) | 2.59 (1.82) | 2.53 (1.66) | 2.20 (1.75) | 1.71 (1.69) | < 0.001¶ |
| Urinary Cd, µg/g creatinine | 3.62 (2.04) | 2.71 (2.01) | 2.55 (1.83) | 1.88 (1.90) | 1.66 (1.98) | < 0.001** |
*Different group by Duncan analysis followed by ANOVA, E4 group vs. other groups; †Different group by Duncan analysis followed by ANOVA, E3 and E4 groups vs. other groups; ‡ P by chi-square test for trend; §Defined as smoking > 20 pack-years for lifetime; ‖Different group by Duncan analysis followed by ANOVA, E1 group vs. E2 and E3 groups vs. E4 group vs. control group; ¶Different group by Duncan analysis followed by ANOVA, E1 group vs. E2, E3 and E4 groups vs. control group; **Different group by Duncan analysis followed by ANOVA, E1 vs. E2 and E3 vs. E4 and control group.