Indoor Environmental

Indoor Environmental and Air Quality (IEAQ) health concerns have increased as a result of energy conservation measures that were instituted for office buildings during the 1970s. These well-intentioned measures resulted in a reduction of fresh outside air infiltration and contributed to the buildup of indoor air contaminants.

EPA studies indicate that indoor air levels of many pollutants may be 2-5 times higher than outdoor levels. This results from the recycling of indoor air within the building air conveyance systems, trapping pollutants and causing their buildup. Common pollutants include dust, mold and spores, pollen, pet dander, smoke, asbestos, odors, radon and carbon monoxide.

Elevated levels of indoor air pollutants can be a concern because estimates show most people spend as much as 90% of their time in an indoor environment. The EPA has ranked IEAQ among its top five concerns.

School Children and Teachers ill from Odors

An elementary school underwent refinishing of its gymnasium. The odors of the coating materials were strong. Teachers and children felt ill. An environmental consulting firm measured hundreds of low-level VOC's in the school. At a town meeting, the parents wanted to know what risk each of them posed to the students. NIOSH came in. They were asked the same questions, but had no satisfactory answers. When we were called, six months into this saga, the parents and teachers were greatly distressed and outraged. We met with parent-teacher working groups on several occasions, met with parent leaders separately, developed a plan for eliminating all odors and conducted a community meeting in which we discussed and explained the toxicology of low-level VOC exposures. There was no risk and, ultimately, the constituents were able to accept that.

Toluene and Xylene Exposure

A middle school had asbestos floor tile removed during the summer. When school reconvened in the fall, teachers and students were reporting odors and related symptoms of malaise, coughing, nausea and headaches, especially in the gymnasium. An industrial hygienist found high levels of toluene and xylene in the air, but could not find a source. ICTM was called to investigate and found the odors were not evident in the gymnasium area which had a wood floor. This led our toxicologist to speak to the asbestos floor tile removal company.

As a result of this inquiry, our physician toxicologist discovered that they had poured a solvent solution onto the asbestos tile and had let it soak into the tile for three days in order to facilitate the tile removal. We pulled up the new tile. Since there was a concrete slab onto which the tile had been laid, the concrete had absorbed the solvent solution which was giving off solvent vapors. ICTM met with parents at a PTA-sponsored barbecue and explained what had been found. A formal plan was developed and presented at both a PTA meeting and County School Board meeting and all parties agreed to the plan. The school was closed for one month, during which time the students were moved to portable classrooms located on the elementary school grounds, the new tile was removed and the concrete left bare. The building was then heated to 90 degrees and large fans were placed in the building in order to volatilize the absorbed solvent. We continuously monitored the air. When the concentration of the volatilized solvents fell to non-detect levels, new tiles were installed, and the students and faculty returned to the building. There was no recurrence of symptoms or complaints of illness.


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