Diurnal Variations and Personal Exposures of Carbonyl Compounds in Different Types of Malls in Nanchang

Abstract

Diurnal variations and personal exposure of carbonyl compounds were investigated in four types of large shopping malls (including department store, supermarket, bookstore and furniture store) in urban district of Nanchang, China. The diurnal measurements both in the summer and winter showed that the concentrations of carbonyls exhibited a higher peak at the morning hour and a lower peak at the evening hour except for acetaldehyde, which obviously peaked at the afternoon hour in winter. The indoor concentrations of LMW carbonyl compounds were found higher than their outdoor counterparts with only a few exceptions. For some high molecular weight (HMW) carbonyls (C5) especially for benzaldehyde and p-Tolualdehyde which might have stronger outdoor source (e.g. vehicle exhaust), resulting in the Indoor/Outdoor ratios below 1. The personal exposures showed that large shopping malls in Nanchang were important microenvironment for exposure to formaldehyde and acetaldehyde.