Cindy Crawford took her children out of school in protest after officials found the outlawed chemical PCB in Malibu schools her children attend.

PCB Found In Malibu High School Classrooms

Crawford and her husband Rande Gerber are parents to two children, daughter Kaia, 12, and son Presley, 14, who attend Malibu public schools. Four out of ten Malibu High School classrooms randomly tested were found positive for PCB. PCB, a chemical used in window caulking in buildings built in the 50s, 60s and early 70s, was outlawed by Congress in 1976 and has been known to cause cancer and damage the reproductive and immune systems with continued exposure.

Cindy Crawford Takes Her Kids Out Of School

While the school says they are removing the window caulking in those four classrooms, they have not tested the caulking in the remainder of the school building. Instead, the school conducted air and dust tests and found no elevated levels of PCB, which is enough to be declared safe. When school started on Tuesday, Aug. 19, Crawford refused to let her children attend.

“I don’t feel 100 percent safe,” Crawford explained in an interview with Today Show correspondent Maria Shriver on Tuesday, Aug. 19.

Awwww! Presley and Kaia. pic.twitter.com/2tyNvEsHhl

— Cindy Crawford (@CindyCrawford) August 4, 2014

Cindy Crawford Interview On Today

Malibu High School insists it is completely safe to resume classes as scheduled, and have pledged to continue conducting regular air and dust tests throughout the year to monitor PCB levels. However, Crawford is still uncomfortable with their findings, specifically the fact that authorities failed to test the caulking in every classroom, choosing instead to rely on air and dust tests, results of which can change week to week.

“I think that air testing and water testing are a piece of the puzzle…The problem is that they haven’t tested the source. Unless they’re testing every day, how do I know it’s safe for my kid?” Crawford added.

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Crawford was just one celebrity who spoke at a rally on Tuesday, Aug. 12, held outside the Malibu Courthouse. Crawford spoke to fellow concerned parents, including actor Joshua Malina, and teachers about the possible PCB contamination, and offered to pay for testing herself.

“Now see if the district will let us. I don’t know how they could possibly say no,” Crawford told the crowd.

Now that she has made the decision to take her kids out of the contaminated school, Crawford says she will continue to fight for more treatment and better regulations regarding PCB in schools, declaring, “This is not a Malibu issue.”

In fact, Crawford and many other parents are suggesting a campaign for stricter national laws regarding PCB testing and treatment.

“I look 10 years down the line. What if my kid, God forbid, had a problem? How could I live with myself if I knew that it was a possibility and I still sent them to school there?” Crawford told Today.