Table 3. Mean concentrations of Pb, Hg, and Cd in whole blood by age groups in study subjects.
| Metals | Age, yr | Male | Female | Total | |||
|---|---|---|---|---|---|---|---|
| No. | GM (95% CI) | No. | GM (95% CI) | No. | GM (95% CI) | ||
| Pb, µg/dL | 0–4 | 193 | 1.45 (1.36–1.55) | 179 | 1.53 (1.41–1.65) | 372 | 1.49 (1.42–1.57) |
| 5–9 | 312 | 1.60 (1.53–1.67)a | 301 | 1.42 (1.36–1.49) | 613 | 1.51 (1.46–1.56) | |
| 10–19 | 438 | 1.55 (1.51–1.60)a | 407 | 1.19 (1.14–1.24) | 845 | 1.36 (1.33–1.40) | |
| 20–29 | 145 | 1.91 (1.81–2.02)a | 154 | 1.51 (1.41–1.61) | 299 | 1.69 (1.62–1.77) | |
| 30–39 | 147 | 2.44 (2.32–2.56)a | 227 | 1.84 (1.76–1.91) | 374 | 2.05 (1.98–2.13) | |
| 40–49 | 198 | 2.70 (2.57–2.84)a | 269 | 1.91 (1.83–1.99) | 467 | 2.21 (2.14–2.29) | |
| 50–59 | 193 | 3.07 (2.93–3.21)a | 291 | 2.31 (2.22–2.39) | 484 | 2.58 (2.50–2.67) | |
| Above 60 | 198 | 3.02 (2.89–3.16)a | 218 | 2.23 (2.14–2.33) | 416 | 2.58 (2.49–2.67) | |
| Hg, µg/L | 0–4 | 224 | 1.91 (1.76–2.09) | 219 | 2.18 (2.02–2.35)b | 443 | 2.04 (1.93–2.16) |
| 5–9 | 323 | 2.02 (1.90–2.15) | 310 | 2.10 (1.98–2.22) | 633 | 2.06 (1.97–2.15) | |
| 10–19 | 443 | 2.20 (2.10–2.31) | 416 | 2.19 (2.09–2.30) | 859 | 2.20 (2.12–2.27) | |
| 20–29 | 145 | 3.36 (3.09–3.65)a | 154 | 2.47 (2.26–2.70) | 299 | 2.87 (2.69–3.05) | |
| 30–39 | 147 | 5.03 (4.58–5.52)a | 227 | 3.26 (3.04–3.49) | 374 | 3.86 (3.64–4.10) | |
| 40–49 | 200 | 5.55 (5.08–6.07)a | 269 | 3.62 (3.38–3.88) | 469 | 4.34 (4.10–4.60) | |
| 50–59 | 194 | 5.66 (5.20–6.16)a | 291 | 3.85 (3.59–4.13) | 485 | 4.49 (4.25–4.75) | |
| Above 60 | 198 | 4.81 (4.42–5.23)a | 218 | 3.43 (3.16–3.73) | 416 | 4.03 (3.79–4.28) | |
| Cd, µg/L | 0–4 | 211 | 0.22 (0.20–0.24) | 199 | 0.22 (0.20–0.25) | 410 | 0.22 (0.21–0.23) |
| 5–9 | 318 | 0.25 (0.24–0.27) | 302 | 0.24 (0.22–0.26) | 620 | 0.25 (0.23–0.26) | |
| 10–19 | 435 | 0.33 (0.31–0.35) | 403 | 0.34 (0.32–0.36) | 838 | 0.33 (0.32–0.35) | |
| 20–29 | 145 | 0.60 (0.55–0.67) | 154 | 0.62 (0.57–0.68) | 299 | 0.61 (0.58–0.66) | |
| 30–39 | 147 | 0.97 (0.89–1.05) | 223 | 1.08 (1.01–1.15)b | 370 | 1.03 (0.98–1.09) | |
| 40–49 | 197 | 1.06 (0.98–1.13) | 266 | 1.30 (1.23–1.37)a | 463 | 1.19 (1.14–1.24) | |
| 50–59 | 194 | 1.14 (1.07–1.21) | 291 | 1.44 (1.36–1.51)a | 485 | 1.31 (1.26–1.36) | |
| Above 60 | 197 | 1.14 (1.07–1.21) | 218 | 1.38 (1.31–1.46)a | 415 | 1.26 (1.21–1.31) | |
Pb = lead, Hg = mercury, Cd = cadmium, GM = geometric mean, CI = confidence interval.
aP < 0.01, statistically highly significant between males and females; bP < 0.05, statistically significant between males and females.