Cindy Crawford has withdrawn her children from school.
The 48-year-old supermodel and her husband Rande Gerber have decided not to allow Presley, 15, and Kaia, 12, to return to Malibu High School after routine soil tests found elevated levels of PCBs - chemicals which can cause cancer and damage immune and reproductive systems - in window caulking in four of 10 classrooms checked at random.
Cindy said: ''I don't feel 100 percent safe....
''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?''
The school plan to remove caulk from the classrooms and periodically monitor for air and dust, but Cindy - who earned a university scholarship to study chemical engineering before embarking on a modelling career - doesn't think they are doing enough because PCB levels can vary from week to week.
Speaking to Maria Shriver for 'Today', she said: ''I'm very frustrated and I'm very disappointed at the way this has been handled.
''The problem is, for me, is that they haven't tested the source.
''I think that air testing and water testing are a great piece of the puzzle. Unless they're testing every day, how do I know that every day it's safe for my kid?''
Cindy has even offered to fund more PCB testing herself and thinks laws around the problem need to change.
She argued: ''This is not a Malibu issue. This is really an issue in a lot of older schools.''
''I just think the laws need to be changed.''
Malibu High School insisted student health and safety is its ''first priority''.
They added: ''Using federal EPA students, our schools are safe for students and employees.''