Lajoie P.,Environmental Health And Toxicology Division Institute National Of Sante Publique Du Quebec Inspq Quebec City |
Aubin D.,National Research Council Canada |
Gingras V.,Environmental Health And Toxicology Division Institute National Of Sante Publique Du Quebec Inspq Quebec City |
Daigneault P.,University of Quebec |
And 10 more authors.
Indoor Air | Year: 2015
A randomized controlled trial was carried out to measure the impact of an intervention on ventilation, indoor air contaminants, and asthma symptoms of children. Eighty-three asthmatic children living in low-ventilated homes were followed over 2 years. Several environmental parameters were measured during the summer, fall, and winter. The children were randomized after Year 1 (43 Intervention; 40 Control). The intervention included the installation of either a Heat Recovery Ventilator (HRV) or Energy Recovery Ventilator (ERV). During the fall and winter seasons, there was a significant increase in the mean ventilation rate in the homes of the intervention group. A statistically significant reduction in mean formaldehyde, airborne mold spores, toluene, styrene, limonene, and α-pinene concentrations was observed in the intervention group. There was no significant group difference in change in the number of days with symptoms per 14 days. However, there was a significant decrease in the proportion of children who experienced any wheezing (≥1 episode) and those with ≥4 episodes in the 12-month period in the intervention group. This study indicates that improved ventilation reduces air contaminants and may prevent wheezing. Due to lack of power, a bigger study is needed. © 2014 John Wiley & Sons A/S. Source