Higher levels of greenness in urban neighborhoods are associated with reduced indoor levels of particulate matter and noise annoyanceThis study was part of a larger research initiative (the HEALS study) in which sensors were used in the homes of families with young children to assess indoor levels of particulate matter (fine airborne particles) and noise. Families participating in this initiative completed questionnaires pertaining to socioeconomic data, household information, and noise annoyance. This initiative included households in four European urban areas and the surrounding environs.
This study linked the indoor exposure monitoring data from 131 households in the HEALS project to measures of greenness around those households. Three metrics of greenspace were used: Normalized Difference Vegetation Index (NDVI), tree cover density and green land use.
Findings showed lower indoor particulate matter (PM2.5) and road noise annoyance were associated with higher levels of greenness as measured by NDVI. No significant associations were observed between indoor noise and greenspace.
These findings have important health-related implications, as fine airborne particles and noise are known environmental risk factors for human illness and disease. Reducing exposure to these risk factors could potentially provide significant health benefits at the population level. Because many people spend as much as 90% of their time indoors, the quality of the indoor environment is of special concern. As it relates to air quality and noise levels, indoor environments are highly influenced by outdoor environments. “Outdoor sources contribute over half of indoor particulate matter (PM 2.5) concentrations and are linked to over 60% of the total burden of disease caused by indoor air pollution exposure in Europe.”
This study was based on findings from previous research indicating that urban greenspace may promote positive pathways to health. One such pathway involves the reduction of harmful exposures, including particulate matter and noise. This study, by examining the impact of greenness on the indoor environment (which has rarely been studied), makes a valuable contribution to our understanding of potential health pathways for urban residents.
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