A Study on Characteristics of Atmospheric Heavy Metals in Subway Station

Abstract

In this study, we investigated the atmospheric heavy metal concentrations in the particulate matter inside the subway stations of Seoul. In particular, we examined the correlation between the heavy metals and studied the effect of the heavy metals on cell proliferation. In six selected subway stations in Seoul, particulate matter was captured at the platforms and 11 types of heavy metals were analyzed. The results showed that the mean concentration of iron was the highest out of the heavy metals in particulate matter, followed by copper, potassium, calcium, zinc, nickel, sodium, manganese, magnesium, chromium and cadmium in that order. The correlation analysis showed that the correlations between the heavy metals was highest in the following order: (Cu vs Zn) , (Ca vs Na) , (Ca vs Mn) , (Ni vs Cr) , (Na vs Mn) , (Cr vs Cd) , (Zn vs Cd) , (Cu vs Cd) , (Ni vs Cd) , (Cu vs Ni) , (K vs Zn) , (Cu vs K) , (Cu vs Cr) , (K vs Cd) , (Zn vs Cr) , (K vs Ni) , (Zn vs Ni) , (K vs Cr) , and (Fe vs Cu) . The correlation coefficient between zinc and copper was 0.937, indicating the highest correlation. Copper, zinc, nickel, chromium and cadmium, which are generated from artificial sources in general, showed correlations with many of the other metals and the correlation coefficients were also relatively high. The effect of the heavy metals on cell proliferation was also investigated in this study. Cultured cell was exposed to 10 mg/l or 100 mg/l of iron, copper, calcium, zinc, nickel, manganese, magnesium, chromium and cadmium for 24 hours. The cell proliferation in all the heavy metal-treated groups was not inhibited at 10 mg/l of the heavy metal concentration. The only exception to this was with the cadmium-treated group which showed a strong cell proliferation inhibition. This study provides the fundamental data for the understanding of simultaneous heavy metal exposure tendency at the time of particulate matter exposure in subway stations and the identification of heavy metal sources. Moreover, this study can be used as the fundamental data for the cell toxicity study of the subway-oriented heavy metal-containing particulate matter.

Airborne copper exposure in school environments associated with poorer motor performance and altered basal ganglia

“…This is consistent with reports indicating that the air in busy train stations contains large amounts of copper generated by overhead train wire supplying electrical power (Kim et al. ; Loxham et al. ).…”

Chemical Characterisation of the Coarse and Fine Particulate Matter in the Environment of an Underground Railway System: Cytotoxic Effects and Oxidative Stress—A Preliminary Study

“…Iron in particular is regarded as characteristic of the particulate matter found in underground systems [ 10 , 13 , 31 ]; in such environments, iron-containing particles are chiefly generated by mechanical wear and tear and friction at the wheel-rail and wheel-brake interfaces and between the pantograph and the overhead cables. These processes initially produce particles of metallic iron, which, on reacting with the oxygen present in the air, are transformed into iron oxide.…”

Correlation between levels of airborne endotoxin and heavy metals in subway environments in South Korea

“…To evaluate the level of the seven heavy metals, they were compared to levels of heavy metals in a previous study conducted in Seoul, South Korea 14 . The results showed that the mean Fe level was the highest of the heavy metals in PM, followed by Zn, Ni, Mn, Cr, respectively 14 .…”