The swimming pool at Berkeley High School in Berkeley, Calif., was shut down last Wednesday, after city officials said the level of chemicals in the water exceeded normal operating conditions, Berkeleyside reported.

The decision was made after parents delivered a letter to the school’s principle the day before, expressing concern over the health of students on the water polo team. According to the letter, the players were displaying some disturbing symptoms, such as burning eyes, bleached hair, and even the disappearance of body hair.

The city came in to test the pool the following day and found that the water showed an “exponentially high” pH level of 8.5, which had been caused by a defective CO2 tank. Pool pH levels should typically be kept between 7.2 and 8.0.

The school’s water polo coach, Bill Gaebler, reported the test results in an email.

“The pH scale is an exponential scale, so 8.5 is very high (10x), and the level of rapid eye and skin irritation due to chloramines rises significantly at levels above 0.6.,” he wrote. “The high pH was caused by a defective CO2 tank, CO2 being the gas that buffers (lowers) the pH.”

Gaebler explained that a new CO2 tank had been ordered and that it should arrive within the next week. He also said that going forward, chemical readings of the pool would be taken three times daily. According to Berkeleyside, this is the second time the Berkeley High School pool has been closed for similar problems with chemical imbalance.

Some parents of children on the water polo team were upset with the school administration for negligence, though they didn’t want to make their complaints into a larger issue.

“We didn’t want the pool closed. We don’t want to make a political issue out of it. We want a safe and healthy environment for our children,” one parent, who wished to remain anonymous, told Berkeleyside. “We didn’t want the school administration to wait until there was a crisis to deal with this issue.”

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