High concentrations of nitrates in drinking water are?

High concentrations of nitrates in drinking water are a recognized concern due to their association with methemoglobinemia, often referred to as "blue baby syndrome." This condition primarily affects infants and is caused by the conversion of hemoglobin into methemoglobin, which is less effective at transporting oxygen in the bloodstream. When infants consume high levels of nitrates, typically found in contaminated well water or agricultural runoff, the nitrates can convert to nitrites in the body. These nitrites then interfere with the ability of red blood cells to carry oxygen, leading to serious health issues.

While adults can tolerate higher levels of nitrates without experiencing significant health effects, the vulnerability of infants necessitates strict guidelines concerning allowable nitrate concentrations in drinking water. Therefore, the potential for methemoglobinemia highlights the critical nature of monitoring nitrate levels to protect public health, especially for vulnerable populations such as young children.