What is the MCL for combined Nitrate and Nitrite?

The maximum contaminant level (MCL) for combined nitrate and nitrite, which refers to the total concentration of these two compounds in drinking water, is set at 10 mg/L. This regulatory standard is established to protect public health, as elevated levels of nitrates and nitrites can lead to significant health issues, especially for vulnerable populations such as infants.

High nitrate levels can cause methemoglobinemia, commonly referred to as "blue baby syndrome," which affects the ability of blood to carry oxygen in infants. Therefore, maintaining the concentration of combined nitrate and nitrite below this MCL threshold is crucial for ensuring the safe consumption of drinking water.

Understanding this MCL also helps operators monitor water quality and comply with regulations to minimize health risks associated with water contaminants.