A simulation model of building intervention impacts on indoor environmental quality, pediatric asthma, and costs

Department of Environmental Health, Harvard School of Public Health, Boston, Mass. Electronic address: .
The Journal of allergy and clinical immunology (Impact Factor: 11.48). 07/2013; DOI: 10.1016/j.jaci.2013.06.003
Source: PubMed


Although indoor environmental conditions can affect pediatric asthmatic patients, few studies have characterized the effect of building interventions on asthma-related outcomes. Simulation models can evaluate such complex systems but have not been applied in this context.
We sought to evaluate the impact of building interventions on indoor environmental quality and pediatric asthma health care use, and to conduct cost comparisons between intervention and health care costs and energy savings.
We applied our previously developed discrete event simulation model (DEM) to simulate the effect of environmental factors, medication compliance, seasonality, and medical history on (1) pollutant concentrations indoors and (2) asthma outcomes in low-income multifamily housing. We estimated health care use and costs at baseline and subsequent to interventions, and then compared health care costs with energy savings and intervention costs.
Interventions, such as integrated pest management and repairing kitchen exhaust fans, led to 7% to 12% reductions in serious asthma events with 1- to 3-year payback periods. Weatherization efforts targeted solely toward tightening a building envelope led to 20% more serious asthma events, but bundling with repairing kitchen exhaust fans and eliminating indoor sources (eg, gas stoves or smokers) mitigated this effect.
Our pediatric asthma model provides a tool to prioritize individual and bundled building interventions based on their effects on health and costs, highlighting the tradeoffs between weatherization, indoor air quality, and health. Our work bridges the gap between clinical and environmental health sciences by increasing physicians' understanding of the effect that home environmental changes can have on their patients' asthma.

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Available from: Patricia Fabian, Sep 03, 2015
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    • "Indoor sources tend to be intermittent and depend on both occupant behaviors and building design; frying, grilling (with and without exhaust fans), burning candles that evaporate oil, and smoking can lead to peak PM concentrations of several hundred µg/m 32425262728. Higher concentrations of particles generated indoors are expected to occur in kitchens and bathrooms, and decrease with the use of exhaust ventilation systems or operation of window and central air conditioning systems[25,29]. Outdoor sources contribute to indoor concentrations through transmission in active (e.g., air handling units) and passive (e.g., open windows and leaks) ventilation systems. Infiltration of outdoor air can lead to high indoor concentrations of outdoor pollutants near industrial or traffic sources[30]. "
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    • "A recent exposure modeling study in multi-unit public housing estimated reductions in PM2.5 by >50% for a combination of interventions that included use of kitchen and bathroom exhaust fans, replacement of gas with electric stoves, introduction of a no smoking policy and improved weatherization in the apartment [47]. No other individual intervention in that modeling study was able to reduce PM2.5 levels by >50%, and use of a portable HEPA air cleaner alone was able to reduce modeled PM2.5 levels by only 25%. "
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