The Presence of Heavy Metals in Urban Snow

Manganese, zinc, lead, copper, chromium and cadmium concentrations in snow collected in an urban area and its environs and snow clumping stations were determined for the snow from an area a]ong the basin of the Toyoliira River which runs tlirough Sapporo City in Hokkaido. These elements were chosen because they can be commonly founcl in mttnicipal, industrial and minlng eMuents. We studiecl the relationship of heavy meta! concentrations against a backgrotincl level, to see whether the heavy metal concentrtttion$ in the snow could be used as an available inclicator of urban pol!ution. The l)eavy metal concentrations in the snow clearly increased as the river approached the center of the city. The maximum value of the Mn, Zn, Cu, Cr ancl Cd in the snow were 161.3, 22.3, 11.2, 9.74, 1.21 and e.13 xig!l, respectlvely. These values were infiuencecl by local pollution in the industrial area of the city and by the effect of the seasonal wincl from the northwest. The heavy meta}s except Mn had a high correlation with each other.