IMPROVING INDOOR AIR IN NEW ZEALAND HOMES: THE RESPIRATORY HEALTH EFFECTS OF NITROGEN DIOXIDE EXPOSURE

Many homes in New Zealand are poorly constructed and maintained for the climate with inadequate heating resulting in winter temperatures that frequently fall below the World Health Organisation recommended level of 18°C. Approximately 30 % of New Zealand homes are heated by unflued portable gas heaters. To investigate the link between the indoor air environment and respiratory health effects in children, we studied 409 households that used unflued gas heaters or electric heating and had an asthmatic child. The study explores differences in children’s respiratory health before and after their home received a new form of heating and insulation if required. In 2006, houses were randomly assigned to the intervention or control group; those in the intervention group (n=195) received improved heating systems prior to the 2006 winter. NO2 and temperature measures were taken in each of the homes along with objective and subjective health measures. NO2 was significantly related to an increase in wheezing, coughing, reliever use, and lower respiratory symptoms, and a decrease in FEV1 readings