Table 1 Participant characteristics and data on e-waste exposure and ADHD among 243 preschool children in Guiyu
Characteristics | Values |
|---|---|
Age (years) | 5.1 ± 1.0 |
Male, n (%) | 141 (58.0%) |
Serum ferritin (ug/L) | 51.8 (20.3–113.9) |
Father’s education level, n (%) |  |
 Illiterate/primary school | 26 (11.1%) |
 Middle school | 145 (61.7%) |
 High school | 52 (22.1%) |
 College | 12 (5.1%) |
Mother’s education level, n (%) |  |
 Illiterate/primary school | 45 (19.3%) |
 Middle school | 134 (57.5%) |
 High school | 38 (16.3%) |
 College | 16 (6.9%) |
Monthly household income, n (%) | Â |
 Poor, n (%) | 38 (16.5%) |
 Moderate, n (%) | 135 (58.4%) |
 Good, n (%) | 58 (25.1%) |
Father’ s work relating to e-waste, n (%) |  |
 Yes | 98 (42.8%) |
 No | 131 (57.2%) |
E-waste workshops around the house, n (%) | Â |
 Yes | 137 (58.3%) |
 No | 98 (41.7%) |
Household tobacco smoke exposure, n (%) | Â |
 Yes | 170 (70.8%) |
 No | 70 (29.2%) |
Status of e-waste exposure | Â |
Blood Pb (ug/dL) | 7.9 (5.1–16.9) |
Blood Cd (ug/L) | 0.95 (0.54–1.57) |
Blood Pb ≥ 10 ug/dL, n (%) | 68 (28.0%) |
Blood Cd ≥ 2 ug/L, n (%) | 3 (1.2%) |
Status of DSM-IV ADHD | Â |
Inattentive score | 7.9 ± 4.7 |
Hyperactive/Impulsive score | 7.2 ± 4.9 |
Total scorea | 15.2 ± 8.6 |
Inattentive type, n (%) | 11 (4.5%) |
Hyperactive/Impulsive type, n (%) | 13 (5.3%) |
Combined type, n (%)b | 7 (2.9%) |
ADHD, n (%)c | 31 (12.8%) |