engleski

Thallium Content in Zagreb Air

Limited industrial use of thallium and its compounds makes its emission unlikely on the global scale. However, thallium is present in relatively large amounts in raw materials and can significantly increase environmental exposure on local and regional level. This paper presents the results of thallium content in total suspended and deposited matter measured over two-year period in the Zagreb air. Twenty-four-hour samples of total suspended particulate matter (SPM) were collected on membrane filters at the average air flow rate of 70 L min-1, from approximately 100 m3 of ambient air. Monthly samples of depositions were collected in a Bergerhof type deposit gauge. Mass concentrations of thallium varied from 0.00 to 5.85 ng/m3 in the two-year period. Thallium content in deposited matter varied from 0.77 to 3.14 ěg/m2 d in the same period. The results were relatively high, especially in deposited matter. It can be assumed that thallium comes from reentrained dust of contaminated soil, probably because of a cement plant which existed in Zagreb 10 years ago and was the main source of thallium emission in the environment.

nije evidentirano

nije evidentirano