Association between arsenic, cadmium, manganese, and lead levels in private wells and birth defects prevalence in North Carolina: a semi-ecologic study

Table 3 Association ^a [PR (95% CI)] between selected metals and birth defects

Defect	Arsenic	Cadmium	Manganese	Lead
1. Spina bifida	0.7 (0.3, 1.4)	0.5 (0.2, 1.4)	0.7 (0.4, 1.4)	1.0 (0.5, 1.7)
2. Anotia/microtia	0.6 (0.2, 2.0)	1.0 (0.3, 4.2)	1.3 (0.5, 3.4)	1.0 (0.4, 2.6)
3. Conotruncals	1.0 (0.6, 1.6)	1.1 (0.6, 2.0)	1.6 (1.1, 2.5)*	0.9 (0.6, 1.5)
4. AVSD/ECD	1.1 (0.5, 2.3)	0.7 (0.2, 1.9)	1.3 (0.6, 2.5)	0.7 (0.3, 1.8)
5. HLHS	0.3 (0.1, 1.0)*	0.8 (0.3, 2.4)	0.5 (0.2, 1.3)	1.7 (0.9, 3.3)
6. Cleft palate (CP)	0.8 (0.5, 1.3)	1.1 (0.6, 2.1)	0.7 (0.5, 1.2)	0.9 (0.6, 1.5)
7. Cleft lip ± CP	1.3 (0.9, 1.9)	1.0 (0.6, 1.7)	1.2 (0.9, 1.8)	1.0 (0.7, 1.5)
8. EA/TEF	1.3 (0.6, 2.7)	0.9 (0.3, 2.4)	0.9 (0.4, 2.0)	1.1 (0.5, 2.3)
9. Pyloric stenosis	1.1 (0.9, 1.5)	0.4 (0.3, 0.7)*	0.8 (0.6, 1.1)	0.8 (0.6, 1.1)
10. Limb reduction	0.5 (0.2, 1.0)	0.6 (0.2, 1.6)	0.7 (0.4, 1.2)	0.7 (0.4, 1.4)
11. Gastroschisis	1.0 (0.5, 1.8)	1.2 (0.5, 2.8)	0.5 (0.2, 1.1)	1.4 (0.8, 2.4)
12. Hypospadias	0.9 (0.7, 1.1)	0.9 (0.7, 1.2)	0.9 (0.7, 1.1)	1.1 (0.9, 1.4)

^aPrevalence ratios were adjusted for maternal age, race, and education status. Metal exposure status was dichotomized as ≥90^th percentile of average census tract metal levels or ≤50^th percentile. Where the 50^th and 90^th percentile of census tract average levels were as follows: 1.29 and 2.54 ppb for arsenic, 0.54 and 1.82 ppb for cadmium, 41.55 and 139.69 ppb for manganese, and 3.52 and 7.28 ppb for lead.
*p < 0.05.
Abbreviations: ‘Conotruncals’ consists of a group of heart defects including common truncus, Tetralogy of Fallot, and transposition of the great arteries; Atrioventricular septal/Endocardial cushion defects (AVSD/ECD); Hypoplastic left heart syndrome (HLHS); Esophageal atresia also called tracheo-esophageal fistula (EA/TEF); ‘Limb reduction’ includes reduction defects of the upper and lower limbs.

ISSN: 1471-2458