Nitrate contamination in drinking water and adverse reproductive and birth outcomes: a systematic review and meta-analysis

Abstract

Exposure to low levels of nitrate in drinking water may have adverse reproductive effects. We reviewed evidence about the association between nitrate in drinking water and adverse reproductive outcomes published to November 2022. Randomized trials, cohort or case–control studies published in English that reported the relationship between nitrate intake from drinking water and the risk of perinatal outcomes were included. Random-effect models were used to pool data. Three cohort studies showed nitrate in drinking water is associated with an increased risk of preterm birth (odds ratio for 1 mg/L NO3-N increased (OR1) = 1.01, 95% CI 1.00, 1.01, I2 = 23.9%, 5,014,487 participants; comparing the highest versus the lowest nitrate exposure groups pooled OR (ORp) = 1.05, 95% CI 1.01, 1.10, I2 = 0%, 4,152,348 participants). Case–control studies showed nitrate in drinking water may be associated with the increased risk of neural tube defects OR1 = 1.06, 95% CI 1.02, 1.10; 2 studies, 2196 participants; I2 = 0%; and ORp = 1.51, 95% CI 1.12, 2.05; 3 studies, 1501 participants; I2 = 0%). The evidence for an association between nitrate in drinking water and risk of small for gestational age infants, any birth defects, or any congenital heart defects was inconsistent. Increased nitrate in drinking water may be associated with an increased risk of preterm birth and some specific congenital anomalies. These findings warrant regular review as new evidence becomes available.

Direct potable reuse and birth defects prevalence in Texas: An augmented synthetic control method analysis of data from a population-based birth defects registry

“…Finally, we did not investigate other adverse pregnancy outcomes that have been linked to drinking water contamination, such as prematurity and low birthweight. 36,37 DPR may increase efficiency and sustainability while reducing costs and wastewater discharge, 38 but concerns regarding the safety and acceptability of this approach remain. Importantly, the lack of an environmental buffer could conceivably result in increased concentrations of contaminants that have been linked to birth defects and adverse pregnancy outcomes in treated drinking water.…”

Hidden toxins: The effects of water quality on pregnancy and infant health

“…A systematic review involving a sample of over 7 million subjects found nitrate in drinking water to be associated with a host of adverse reproductive and birth outcomes, including an increased risk of preterm birth, at nitrate levels below the current regulatory levels. 5 Some case studies also showed that nitrate in drinking water may be associated with an increased risk of neural tube defects (NTDs), although the result does not appear to be robust across samples. As with other correlational analyses, caution is warranted in interpreting results as causal or in making quantitative inferences about the magnitude of impacts.…”

Confinement engineering for enhanced electrocatalytic nitrate reduction by integrating B-doped graphene with iron catalysts for long-term stability

“…Because of the large amount of nitrogenous wastewater discharged from agriculture and industry and the extremely high solubility of NO 3 − in water, the nitrogen cycle in ecosystems has been severely disrupted, thereby endangering human health. 1 Therefore, numerous researchers are striving to restore balance to the nitrogen cycle. [2][3][4] Common NO 3 − removal methods include physical, biological, and chemical methods.…”