Question: who nitrate standards in drinking water?
Answer: The maximum contaminant level (MCL) for nitrate in public drinking water supplies in the United States (U.S.) is 10 mg/L as nitrate-nitrogen (NO3-N). This concentration is approximately equivalent to the World Health Organization (WHO) guideline of 50 mg/L as NO3 or 11.3 mg/L NO3-N (multiply NO3 mg/L by 0.2258).