MT. PULASKI, Ill. (WAND) - High levels of nitrate in Mt. Pulaski water might be dangerous for infants to drink, city leaders said in a press release. 

They said water sample results received Dec. 26 showed nitrate at 11 mg/L, which is above the maximum contaminant level (MCL) of 10 mg/L. They said children younger than six months old should not drink the water, as high nitrate levels can cause serious illness and possibly death in infants. 

Those symptoms can include blue baby syndrome, which involves blueness of the skin as a symptom. Symptoms can happen quickly, with an infant's health getting worse over a period of days. Should an infant show these symptoms, parents are asked to seek medical attention for them immediately. 

Parents should use bottled water or water low in nitrates when giving an infant water, juice or formula.

People in Mt. Pulaski are also asked to not boil water, as boiling, freezing, filtering or letting water stand won't reduce the nitrate level. 

"Excessive boiling can make the nitrates more concentrated, because nitrates remain behind when the water evaporates," the Mt. Pulaski release said.

Mt. Pulaski leaders said nitrate can come from "natural, industrial or agricultural sources" such as septic systems and run-off. Levels can vary during the year, and authorities said they will continue to monitor water for safer levels. 

"We are now testing the water each month for nitrate," the release said. "We are also working with the EPA to design a system that can reliably deliver water well below the maximum level. As things progress, we will keep you informed." 

Adults and children older than six months can drink the tap water, authorities said.