Nitrate contamination in infant formula: Occurrence and health risk assessment in Iran

This study evaluated nitrate levels in infant formulas as potential major source of nitrate exposure among Iranian infants and assessed the associated health risks. Sixty samples representing six popular consumed infant formula brands were analyzed using an optimized ion chromatography method. The analytical procedure employed a mobile phase consisting of sodium hydrogen carbonate (3.2 mmol/L) and sodium carbonate (1 mmol/L) at a flow rate of 1 mL/min, with method recoveries exceeding 88%. Nitrate concentrations ranged from 15.1 to 88.6 mg/kg, with an overall mean level of 39.4 ± 13.8 mg/kg. All measured nitrate levels were below the maximum permissible limit established by the European Commission. Health risk assessment indicated that nitrate intake from formula consumption under typical feeding conditions did not exceed the acceptable daily intake (ADI), and short-term exposure was unlikely to cause adverse effects. Although no non-carcinogenic risk was identified, the margin of safety was significant reduced. Therefore, despite nitrate concentrations remaining within acceptable regulatory limits, exposure through infant formula may still represent a potential risk of methemoglobinemia in susceptible infants, highlighting the importance of continuous surveillance and routine monitoring by national food safety authorities.