Formaldehyde Levels and the Factors Affecting These Levels in Homes in Perth, Western Australia

Abstract

Formaldehyde is a highly irritant gas commonly encoun tered in indoor environments. Domestic levels of formal dehyde may vary with building practices and climate and the aim of the present study was to investigate formalde hyde levels in 185 homes in Perth, Australia. The formal dehyde was monitored using a validated passive sam pling technique. Levels were measured in four rooms of each house (living room, kitchen and large and small bedrooms). In 160 homes the monitoring was repeated 4-7 months later in a different season to the original measurement. It was found that within homes there was no significant difference in formaldehyde concentrations measured in the four rooms. For the first sampling peri od, the geometric mean of the average household con centration (average of the four rooms) for all homes was 22.8 ppb and ranged from 3.0 to 92.3 ppb. Only the age of the house (p < 0.0001) and the season of monitoring (p < 0.0001) were significant predictors of indoor levels, high er levels in newer homes and in homes monitored in summer. Mean concentrations were lower during the fol low-up monitoring, but only in houses that were less than 10 years old or in houses that were initially moni tored in summer. Overall formaldehyde concentrations were low and rarely exceeded the Australian guideline level of 100 ppb. There seemed to be good inter-room mixing of formaldehyde within homes. Concentrations were significantly affected by season and age of the house.