A comparative study on physicochemical characteristics of household dust from a metropolitan city and a remote village in China

Özet

The physicochemical characteristics of household dust in a typical metropolitan city (i.e., Beijing, theurban region) and a remote village in western of China (the rural region) were investigated andcompared. The results show that the particles of household dust in both the regions could be classified assix types: micro-aggregates, biogenic, spherical, subrounded, subangular, and angular in morphology.Most dust particles were found to belong to the latter three types and belonged to mineral particles. Theaverage particle size (aerodynamic equivalent diameter) of household dust was 16.1 and 14.9 mm in therural and urban regions, respectively. Dust particles with diameters 10e20 mm were the highest bynumber in the both regions, while dust diameters from 30 to 40 mm and from 20 to 30 mm were thehighest by volume in the urban and rural regions, respectively. The minerals in household dust particlesin both the rural and urban regions were primarily quartz, albite, calcite, and dolomite. The averagepercentages of macro-element species (Si, Al, Ca, Fe, K, Mg, Na, P, and Ti) in household dust in the ruraland urban regions were lower than those in the corresponding outdoor dust and their backgroundvalues, except for Ca. Silicon, Al, Ca, Fe, and K were the predominant elements distributed in householddust in both the rural and urban regions. The concentrations of the studied macro-elements in the ruralhousehold dust were lower than those in the urban household dust, being in agreement with therelationship of the reference crust element content in the rural and urban regions. The average percentagesof the ions in the rural and urban household dust were generally higher than those in thecorresponding outdoor dust. The levels of SO42, NO3, Cl, and Ca2þ in the urban household dust werehigher than those in the rural, owing to human activities. The deposition rate of household dust in therural region (i.e., 15.3 ± 2.6 g m2 year1) was approximately 10 times greater than that observed in theurban region due to worse tightness of the houses. Dust at homes was one of the significant sources ofPM10 in the residential environment through resuspension, and the studied properties of household dustare closely related to human health. Household dust in both the rural and urban regions of China shouldnot be ignored.