What is the Primary MCL for total nitrate, which is associated with Blue Baby Syndrome?

The primary Maximum Contaminant Level (MCL) for total nitrate in drinking water is 10 mg/l. This limit is established to protect vulnerable populations, particularly infants under six months old, from health risks associated with elevated nitrate levels, such as Blue Baby Syndrome (methemoglobinemia). This condition prevents the blood from carrying adequate amounts of oxygen, leading to serious health issues. The MCL is based on scientific studies and health assessments, ensuring that drinking water remains safe and free from contaminants that can pose health risks, particularly for sensitive populations.

The guideline of 10 mg/l serves as a preventive measure to maintain water quality and safeguard public health, particularly among vulnerable groups such as infants.