What is the maximum contaminant level for nitrate in water, measured in mg/L?

The maximum contaminant level (MCL) for nitrate in drinking water is set at 10 mg/L. This standard is established to protect human health, particularly for vulnerable populations such as infants and pregnant women. Elevated levels of nitrate can lead to serious health issues, including methemoglobinemia or 'blue baby syndrome,' which affects the ability of blood to carry oxygen in infants.

The set MCL is based on comprehensive studies and assessments of the risks associated with high concentrations of nitrate, making 10 mg/L the threshold deemed safe for consumption. Regulatory agencies monitor and enforce this limit to ensure that public water supplies remain safe for all users. Therefore, the correct answer highlights the appropriate health and safety standard related to nitrate levels in water.