Table 4.

Contamination of the household water supply and congenital heart disease: Main findings from the literature.

Author Ref.	Article Type	All CHDs or Any CHD Subtypes	Study Limitations
Nieuwenhuijsen et al. [46]	Meta-analysis	Trihalomethanes: All CHDs: OR 17% (95% CI: 3, 34) VSDs: OR 58% (95% CI: 21, 107)	Small number of studies. Differences in exposure measurement and cut-off points.
Grazuleviciene et al. [47]	Cohort study	All CHDs: Brominated trihalomethanes: No dose response relationship. Bromodichloromethane exposure during first month of gestation: OR 2.16 (95% CI: 1.05, 4.46).	Subjects were interviewed on water usage in last trimester, not first month, possibly leading to recall bias.

Abbreviations: VSD: Ventricular septal defect.