engleski

CADMIUM CONTENT IN SUSPENDED PARTICULATE MATTER IN ZAGREB AIR

This paper presents the results of cadmium monitoring in total suspended particulate matter (TSPM) in Zagreb air at two measuring sites (city centre and the northern, residential part of the city) for 20 years (1984-2003). Samples of TSPM were collected over 24-hour periods (noon to noon) on membrane filters (Millipore SSWP 09025, pore size 0.8 &micro ; ; m) at the average air flow rate of 70 L min-1, from approximately 100 m3 of ambient air. Samples were destroyed in nitric acid and cadmium was determined by atomic absorption spectrometry. Over the 20 years of monitoring, the annual means of cadmium concentrations varied from 0.5 to 5.9 ng m-3 in the city centre and from 0.4 to 3.1 ng m-3 in the residential part of the city. Cadmium concentrations in the residential part were in average 32% lower than in the city centre. However, cadmium concentrations in Zagreb air were below the recommended value (RV) of 0.01 &micro ; ; g m-3, according to the Law on Air Quality Protection in Croatia. With respect to cadmium in TSPM, Zagreb air is of the 1st category – clean air (concentration levels of air pollution are below RV).

heavy metal; air quality monitoring; atomic spectrometry

nije evidentirano