Morgantown, WV: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, HETA 2009-0172-3124, 2011 Mar; :1-312
In June 2009, school district management requested a health hazard evaluation to investigate concerns about indoor environmental quality at an elementary school. Since August 2005, after renovations and the addition of three classroom wings, there have been many issues regarding indoor environmental quality, including building-related symptoms and a history of dampness, mold growth, high humidity, and ventilation problems. Since 2005, the school district has had many consultants evaluate the school; we briefly summarize their findings in this report. In July 2009, a NIOSH team visited at the elementary school. We worked in conjunction with the Turner Building Science and Design Group, hired by the school district. We found (1) a musty, moldy odor in the basement, crawl space, and occupied space in the media center; (2) surface drainage issues around the school; (3) a blocked storm drain with standing water; (4) a damaged roof; (5) inadequate flashing; (6) moisture in the gym’s exterior concrete block wall; (7) pressure airflow issues between conditioned and unconditioned spaces; and (8) outdoor humid air entering through the classroom wing soffits. Except for the musty odor in the basement and crawl space under the media center, these findings were consistent with previous findings by consultants. During the site visit, we met with the medical director and other staff of the county health department and reviewed results of a questionnaire they had offered to the staff and parents of the school during May 2009. The health department shared de-identified data with us; our analysis indicated that, during the 2008/2009 school year while in the school building (1) 31% of staff and 13% of students had difficulty breathing/asthma attacks; (2) 52% of staff and 28% of students had one or more upper respiratory symptoms; (3) 75% of staff and 28% of students had eye symptoms; (4) 92% of staff and 49% of students had headaches; (5) 44% of staff and 6% of students had fatigue; and (6) 25% of staff and 20% of students had nosebleeds. Some school staff members who were interviewed over the telephone by a NIOSH medical officer reported building-related symptoms that were suggestive of hypersensitivity pneumonitis, an uncommon and potentially chronic condition known to be related to damp buildings. In August 2009, the school remained closed for remediation after summer break. The school district worked with the Turner Group and other consultants to address issues identified during the July 2009 site visit. The school reopened on February 22, 2010. During March 2-4, 2010, NIOSH investigators administered a health questionnaire to the elementary school staff. Compared with results of the previous health department survey, the NIOSH survey found that fewer staff reported headaches, sneezing, throat symptoms, eye symptoms, cough attacks, fatigue, nosebleeds, and difficulties remembering things or concentrating, consistent with a resolution of many employees’ symptoms while out of the school building. The prevalence of nasal symptoms and skin symptoms were higher in the NIOSH questionnaire than the health department survey, but fewer than 25% of those with these symptoms in the NIOSH survey reported they were work-related. Of staff that participated in the health department survey and worked at the school during the 2008/2009 school year, 74% reported they had symptoms that went away after leaving the school building, consistent with a work-related pattern. The 3%-7% prevalences of lower respiratory symptoms (i.e., shortness of breath, chest tightness, wheezing, and cough attacks) noted in the NIOSH questionnaire were much lower than prevalences of the two lower respiratory symptoms (breathing difficulty/asthma attacks (31%) and cough (15%)) in the health department survey. At the time of the March 2010 NIOSH questionnaire, the overall prevalences of ever and current physician-diagnosed asthma among participating school staff in the NIOSH survey were not significantly different than what would be expected in North Carolina when compared to the BRFSS survey of the North Carolina adult population. Most staff reporting asthma had experienced asthma prior to beginning employment at the elementary school. Compared to the U.S. adult population in the NHANES III, a nationally representative survey, the elementary school employees had significantly lower than expected rates of lifetime and current asthma, chronic bronchitis, shortness of breath on exertion, and nasal allergies, including hay fever. When we compared the elementary school employees who participated in the NIOSH survey to U.S. office workers in the BASE study, we found no excess of work-related upper and lower respiratory symptoms, headache, unusual tiredness and fatigue, or dry itchy skin among the school employees. The NIOSH health survey showed apparent resolution of many health symptoms likely associated with indoor environmental quality issues in the school building before remediation. If there are no future concerns, there may be no reason to resurvey the employees who have reoccupied the school. However, if concerns do arise in the future, another questionnaire can be administered to employees and compared to the NIOSH assessment to determine if increases in building-related symptoms have occurred. No specific environmental measurements are known to predict health outcomes for individuals, so assessing health is the only option for determining the adequacy of building remediation in improving indoor environmental quality.