Mercury concentrations in air and in condensed steam coming from fumar
olic activity at the Solfatara crater (Phlegraean Fields - Italy) were
determined. In the condensed steam, mercury was found mainly associat
ed as Hg-S complexes and showed a flux in the range from 0.9 to 4.5 g
day(-1). Using the point monitor technique, high values (up to 690 ng
m(-3)) of atmospheric mercury levels were observed only close to the m
ain exhaling areas, while background levels (2 ng m(-3)) were measured
over the crater area using the lidar technique. An upper limit (<2.4
g day(-1)) for the flux of elemental mercury in air was estimated with
the lidar. This remote sensing technique also allowed to assess an up
per limit for the SO2 flux (<24 kg day (-1)).