(MALIBU, Calif.) -- School officials in Malibu, Calif., have launched an investigation into complaints that teachers' recent cancer diagnoses and other health problems may have been brought on by toxins on campus.
Twenty-one teachers at Malibu High School voiced concerns that their "health has been adversely effected [sic] as a result of working in our particular buildings," according to a letter addressed to Santa Monica-Malibu Unified School District's risk management specialist Gary Bradbury.
Three teachers at the school, which includes grades six through 12, have been diagnosed with thyroid cancer within the last six months, the letter said, and another teacher has bladder cancer.
In addition, the staff members list migraines, skin rashes, unexplained hair loss and respiratory problems as some of the medical conditions plaguing the staff over the past five years, the letter from the teachers said.
The complaints came after the district hired a contractor to remove soil from the middle school quad in 2010. The soil contained carcinogenic PCBs, lead and other pesticides, according to ABC News' Los Angeles affiliate KABC-TV.
Each of the teachers who has complained of health issues works within the main school building, the music and drama building, the visual arts building or the school's theater, the letter said.
The teachers are demanding the district have each of their classrooms and the school's theater tested for mold and asbestos, among other toxins, the letter said. They also want the school to test the soil outside and underneath the buildings they work in.
Santa Monica-Malibu Unified School District superintendent Sandra Lyon said the school hired environmental consultants to address teachers' health concerns, in a message to Malibu High School Staff on Friday.
"Some have also questioned the nature of the soil removed from the Middle School Quad. We take these concerns and questions seriously and, as a result, will provide a full environmental evaluation of the campus," the memo said. "Please know that safety of our staff and students is a primary concern."
Testing on school grounds began on Sept. 20, Lyon said.
During the course of their review, inspectors will speak with teachers about their ailments, review the 2010 soil remediation project report and see if there are any campus-wide factors that could be linked to health problems.
"Although we don't have any reason to believe that there's any contamination at this school, and we believe the school is safe, we're going to take every precaution to make sure that is in fact the case," school Principal Jerry Block told KABC-TV.
However, it is difficult to establish a causal relationship between these environmental contaminants and cancer, said Robert Giese, a professor at Northeastern University and a director at the Environmental Cancer Research Center.
"If this excavation took place in 2010, that's typically not enough time to get cancer underway. It's more like 10 to 15 years," he told ABC News. "We know that the environment, in the broadest sense, is responsible for 60 percent to 90 percent of all cancers. But there's a huge issue of susceptibility."
"In terms of the statistics of it, there are so few cases," Giese said of the teachers who are speaking out. "It's a pretty small population."
"Whenever you hear that there's a possible cancer cluster, you should be concerned," ABC News' Chief Health and Medical Editor Dr. Richard Besser said. "But it's so hard to know with a cancer cluster whether it's truly related to something in the environment or just a coincidence."
But parents whose children are on campus every day told KABC-TV that they had not been made aware of the health issues.
"I'm afraid. My children spend all day here and if it's not safe, it's a big concern. Everybody is afraid of cancer," said Carrie Krase.
"My biggest concern is that we find out more information about what exactly is going on in the middle school and what environmental issues are possibly a problem for not only the teachers but all the children," said Seth Jacobson, who has a sixth-grader who attends the school.
Malibu High School Parent Teacher Student Association President Amy Young declined to comment to ABC News. Executive Environmental, which was hired by the district to perform testing, and Bradbury also declined to comment.
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