CAMERON, Mo. — Despite a state report that says otherwise, a Kansas City personal injury law firm told residents Saturday that their five-month investigation shows a larger than expected number of cancer cases among the town’s 6,500 residents.

Dr. James Dahlgren, a California toxicology expert made famous by a movie about Erin Brockovich, said the high incidences are the aftereffects of the former Rockwool Industries insulation plant, which operated in Cameron for 18 years, between 1974 and 1992.

Ms. Brockovich was to speak in Cameron on Monday, but organizers said she postponed due to a scheduling conflict.

Saturday’s town hall meeting was attended by about 50 residents — many themselves diagnosed with brain tumors.

It came just two days after another town hall meeting in which a state epidemiologist told residents that brain tumor cases in a four-county area near Cameron isn’t statistically higher than the numbers throughout the state.

Dr. Dahlgren said the law firm he has been hired by — Peterson and Associates — is representing about 40 brain tumor cases in Cameron.

Citing a town population of 6,500, he said that number is “higher than it should be” when considering 15 out of 100,000 malignant cancer cases would be a high incidence in any other part of the country.

Answering an audience question about the validity of the state investigation, Dr. Dahlgren said his experience as an expert on numerous toxic exposure cases across the country has been that the state investigates the community in a way so that they’re not compelled into action and made to run into “a political buzzsaw.”

He said the town’s drinking water doesn’t appear to be the source.

Attorney Dave Peterson said his firm has been investigating the matter since news about Cameron contamination fallout broke in May.

Through independent water and soil tests as well as multiple interviews, he said the firm has determined that slag — a lava-like by-product of producing mineral wool — tests higher for arsenic and lead in samples taken in Cameron.

State health officials previously reported that the high levels of lead and arsenic were not to the health threat level and that they had no proof that the metals reached people through ingestion, inhalation or skin contact.

However, attorneys said Saturday that they’ve interviewed witnesses and have uncovered likely legal violations relating to the Rockwool facility. Mr. Peterson said the company “surreptitiously” burned materials in violation of environmental laws.

Before the town hall meeting, residents lined up to view a map locating many brain tumor patients in the area.

“It’s so serious with that plant there,” said one elderly woman.

“I live right there,” another man said.

“And these are the people that we are just aware of,” said Attorney Todd Matthews.

Attorneys actively noted names of possible tumor victims.

Ahmad Safi can be reached at ahmadsafi@npgco.com.