After a month of study by an independent lab of dust samples gathered from the old North Whidbey Middle School, Oak Harbor School District officials learned Monday what in the school could have been making people sick.

A “high dust load” and a high concentration of glass fibers from the building’s acoustic ceiling tiles are named as particles found in the school that could have made people ill, said the microscopist that conducted the testing.

“From the samples I saw I certainly would not be surprised that people had health problems,” said E.R. Crutcher, a consultant with Microlab Northwest.

However, Crutcher said it is more difficult to draw the conclusion that the school is making people sick.

No evidence of a fungal growth problem exists in the samples studied, said Crutcher, in both a written report and a verbal presentation to district officials.

The highest concentrations of glass fibers were found in samples taken from the B Wing of the interim school site, which is where staff that was allegedly made ill worked, and in the gymnasium.

Recent work to the ceilings of both those areas probably contributed greatly to the amount of glass fibers found there, said Rick Schulte, superintendent of Oak Harbor schools.

Crutcher’s report states that the glass fibers found tend to be “shorter than 500 micrometers,” and “these short glass fibers can cause rashes, nasal congestion, sinus headaches, bloody nasal discharge, sore throat, upper lung congestion, and irritated eyes.”

Effects are not long-lived, however. “Fortunately those symptoms will disappear over time,” Crutcher said Monday.

All of the samples, taken throughout the school building, “have a problem with total particle loading,” Crutcher’s report states.

“The cleaning process (was) not quite as rigorous as it might have been,” Crutcher said Monday. Certain pollen found in the samples had to have been there since at least last summer, he said.

The school, as indicated by the samples Crutcher examined, is cleanable, he said.