Lake Norman High School students in Iredell County are using bottled water this week. Tests of the school’s drinking water supply revealed the chemical perchlorate in the water, which is used in the production of rocket propellant and fireworks.
The chemical may affect the thyroid in those exposed to it for an extended period of time. Iredell-Statesville Superintendent Brady Johnson says the water-testing at all 36 of the county’s schools were prompted by the testing for lead in the drinking water at Charlotte-Mecklenburg schools. Numerous schools tested positive for lead in water fountains and sinks.
“So we decided to test the water in all of our 36 schools," Johnson said. "All of our schools were fine, but Lake Norman High School did have an elevated — significantly elevated — level of perchlorate."
Johnson says two other schools tested positive for perchlorate but the levels miniscule and well below state and federal regulations. He says those schools' drinking water comes from a well and Lake Norman High's comes from the municipal water supply.
"What’s really perplexing to us is that the municipal water supply line that feeds Lake Norman also feeds six other schools that are fine, but yet Lake Norman came back with an elevated level. We're still trying to find the source (of the perchlorate),” Johnson said.
Johnson said it may be a case of human error and the water at the high school was retesed twice this week. In the meantime, until those results are available, students and staff are being given bottled water and it is also being used in the cafeteria for cooking.
The chemical discovery at the school coincides with a state investigation of higher-than-normal cases of thyroid cancer in the part of the county where the schools are located.
Johnson says the thyroid cancer correlation and the perchlorate found in the water are separate issues, for now.