Table. Demographic Characteristics of Children by Blood Lead Level.
| Characteristic | Total No. | Blood lead level, μg/dL, No. (%) | ||||||
|---|---|---|---|---|---|---|---|---|
| <1.0 | 1.0-1.9 | 2.0-2.9 | 3.0-3.9 | 4.0-4.9 | 5.0-9.9 | ≥10.0 | ||
| All children | 1 141 441 | 565 349 (49.5) | 408 689 (35.8) | 99 885 (8.8) | 30 839 (2.7) | 15 507 (1.4) | 15 963 (1.4) | 5209 (0.5) |
| Blood source | ||||||||
| Venous | 844 961 | 441 738 (52.3) | 279 960 (33.1) | 68 616 (8.1) | 22 016 (2.6) | 11 622 (1.4) | 15 843 (1.9) | 5166 (0.6) |
| Capillary | 296 480 | 123 611 (41.7) | 128 729 (43.4) | 31 269 (10.6) | 8823 (3.0) | 3885 (1.3) | 120 (0.04) | 43 (0.01) |
| Sexa | ||||||||
| Female | 554 172 | 278 213 (50.2) | 197 849 (35.7) | 47 024 (8.5) | 14 279 (2.6) | 7121 (1.3) | 7313 (1.3) | 2373 (0.4) |
| Male | 586 703 | 286 770 (48.9) | 210 721 (35.9) | 52 816 (9.0) | 16 548 (2.8) | 8373 (1.4) | 8646 (1.5) | 2829 (0.5) |
| Age group, y | ||||||||
| <1.0 | 114 685 | 65 888 (57.5) | 34 953 (30.5) | 8528 (7.4) | 2517 (2.2) | 1220 (1.1) | 1220 (1.1) | 359 (0.3) |
| 1.0-1.9 | 411 833 | 201 190 (48.9) | 151 288 (36.7) | 35 931 (8.7) | 10 907 (2.7) | 5348 (1.3) | 5407 (1.3) | 1762 (0.4) |
| 2.0-2.9 | 287 526 | 131 750 (45.8) | 109 203 (38.0) | 27 920 (9.7) | 8469 (3.0) | 4301 (1.5) | 4402 (1.5) | 1481 (0.5) |
| 3.0-3.9 | 129 162 | 61 161 (47.4) | 47 268 (36.6) | 11 840 (9.2) | 3947 (3.1) | 1966 (1.5) | 2214 (1.7) | 766 (0.6) |
| 4.0-4.9 | 120 411 | 61 951 (51.5) | 41 900 (34.8) | 9732 (8.1) | 3110 (2.6) | 1621 (1.4) | 1599 (1.3) | 498 (0.4) |
| 5.0-5.9 | 77 824 | 43 409 (55.8) | 24 077 (30.9) | 5934 (7.6) | 1889 (2.4) | 1051 (1.4) | 1121 (1.4) | 343 (0.4) |
| Latitude (degrees)b | ||||||||
| Northern (>40) | 505 841 | 262 765 (52.0) | 156 846 (31.0) | 50 106 (9.9) | 15 898 (3.1) | 8048 (1.6) | 9058 (1.8) | 3120 (0.6) |
| Central (32-40) | 482 470 | 207 780 (43.1) | 207 133 (42.9) | 41 138 (8.5) | 12 523 (2.6) | 6276 (1.3) | 5881 (1.2) | 1739 (0.4) |
| Southern (<32) | 151 206 | 94 172 (62.3) | 43 822 (29.0) | 8426 (5.6) | 2351 (1.6) | 1143 (0.8) | 954 (0.6) | 338 (0.2) |
SI conversion factor: To convert blood lead level to micromoles per liter, multiply by 0.0483.
a
Missing data for 566 patients.
b
Missing data for 1924 patients.