Reexamining the risks of drinking-water nitrates on public health.
Year: 2014
Type: article
Abstract: BACKGROUND: Nitrates in drinking water are generally considered the sole source of nitrite poisoning with methemoglobinemia in infantile methomoglobinemia (IM). However, IM, which occurs during the first 4 months of life, is actually a constellation of cyanosis and hypoxia associated with methemoglobinemia that can result from several other causes. METHODS: This review reexamines the role of nitrate levels in drinking water as a cause of IM and identifies other sources of nitrates that can affect public health and cause chronic diseases. RESULTS: Causes of IM include nitrites in foods, environmental chemical exposures, commonly prescribed pharmaceuticals, and the endogenous generation of oxides of nitrogen. Infants with congenital enzyme deficiencies in glucose-6-phosphate dehydrogenase and methemoglobin reductase are at greater risk of nitrite-induced methemoglobinemia from nitrates in water and food and from exposures to hemoglobin oxidizers. CONCLUSION: Early epidemiological studies demonstrated significant associations between high groundwater nitrate levels and elevated methemoglobin levels in infants fed drinking water-diluted formulas. However, more recent epidemiological investigations suggest other sources of nitrogenous substance exposures in infants, including protein-based formulas and foods and the production of nitrate precursors (nitric acid) by bacterial action in the infant gut in response to inflammation and infection.
Source: Europe PMC (PubMed Central)
Authors: Alyce M Richard, James H Diaz, Alan David Kaye
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2195100431