The Effects of Height on the Accumulation of n-Alkanes and Polycyclic Aromatic Hydrocarbons (PAHs) in Air-Conditioning Filter Dust from High-Rise Apartments

Abstract

To assess the effect of floor levels of high-rise apartment buildings on the accumulation of contaminants in indoor environment, residential air-conditioner filter dust (ACFD) samples from the 1 st , 10 th , 20 th and 30 th floors of a high-rise apartment building were collected for the determination of n-alkanes and polycyclic aromatic hydrocarbons (PAHs). The results show that both n-alkanes and PAHs in the residential ACFD were ubiquitous but varied greatly in concentrations. The total concentrations of 27 n-alkanes (Σ 27 AK) and 16 PAHs (Σ 16 PAH) ranged from 1.35 to 9290 µg g -1 and 278-34200 ng g -1 , respectively. Source apportionment revealed that n-alkanes were from mixed sources combining fossil fuel combustion, natural emission and solid biomass burning, but PAHs were mainly from indoor sources. Furthermore, the diagnostic ratio of paired low weight molecular PAH species may change during transportation and accumulation. Significantly higher concentrations of Σ 27 AK and Σ 16 PAH were observed in the samples from low floor levels (the 1 st and 10 th floors) compared to those from high floor levels (the 20 th and 30 th floors). The results of classification and regression tree analysis clearly suggested floor level is the most important factor influencing the accumulation of Σ 27 AK and Σ 16 PAH in the ACFD. Our findings imply that people living on lower floor levels have greater exposure risks to PAHs associated with indoor dust.

Vertical Distribution Characteristics and Source Apportionment Of Heavy Metals in Urban Near-Surface Dust Based on Receptor Model

“…In all functional areas, the Ni content of HRD were all greater than that in RDS (Table 3) and this general trend is consistent with conclusion of Zhang et al [7] that heavy metal content in dust gradually increases with floor height; whereas, as can be seen from Fig. 2, the Ni concentrations of road dust were higher in EA1(3), EA3(3), EA4(1) and CA1 (2), which can be attributed to the existence of urban surface point source pollution in campus and business districts. The RSDs of Ni in RDS are larger than that in HRD, implying that the Ni concentration of dust is greatly affected by human activities on the ground.…”

“…The pollution load value of RDS in the sample point of CA1( 2) is highest (PLI = 6.24), which is larger than in the other two sample points of CA1 (2.08 and 3.27), representing apparent surface point source pollution. The PLI values of HRD are higher than those of RDS at other research points, except for EA3(3), EA4(1) and CA1 (2), where the index values of RDS are higher than those of HRD. In HRD, expect the sampling point of EA3(3), the PLI values of other research points are all greater than 2.…”

“…However, the higher concentration of Zn in RDS in EA1(2), EA3(3), EA4(1) and CA1(2) can attribute to the urban ground point source pollution. Analogously, arsenic concentrations in RDS are lower than that in HRD, except in EA3(2), EA4(1) and CA1 (2), where the contents of As are higher in RDS. And the Cd concentrations in RDS are lower than those in HRD, except in EA3(3), EA4(1), CA1(2) and CA2 (2).…”

“…Analogously, arsenic concentrations in RDS are lower than that in HRD, except in EA3(2), EA4(1) and CA1 (2), where the contents of As are higher in RDS. And the Cd concentrations in RDS are lower than those in HRD, except in EA3(3), EA4(1), CA1(2) and CA2 (2). Except for the points of EA3(3), EA4(1), CA1(1), CA1(2), the Pb contents of RDS in other sampling points are lower than that of HRD.…”

“…In the process of the rapid advancement of urbanization, human activity space has been greatly extended in height and high-rise buildings are ubiquitous, especially in urban cities [1,2], which lead to an expectation of upper air quality in the modern city. Compared with road dust [3], the atmospheric dry sedimentation particles that sink on the top layer of city buildings can better reflect the contamination status of heavy elements (HEs) adsorbed in the atmospheric particulate matter.…”