Exposure assessment to mercury vapor in chloralkali industry.

The aim of the study was to develop a sampling method aimed at individual sampling of mercury vapor and subsequent individual exposure assessment of the worker. Hopcalite available from Inowroclawskie Zaklady Chemiczne (in Poland) was found useful for mercury vapor sampling in active and passive individual samplers. However the sampling rate determined for passive sampler in steady-state laboratory chamber cannot be used under fluctuating conditions of mercury vapor concentration and air movement typical for field measurement. In order to check comparativeness of passive and active sampling methods, samples were taken in the same time and individual samplers fixed to worker's clothes were used. Mercury vapor concentration was measured at two chloralkali industries in Poland and the results were presented. Excessive exposure in both industries was confirmed by finding elevated mercury concentration in urine samples from the workers.

Emission of mercury to the atmosphere from industrial sources in Poland.

The emission factors of mercury and calculation of annual emission into the atmosphere from different industrial sources in Poland are presented. The emission factors in turn depend on mercury concentration in raw materials, as well as on the character of a technological process. The combustion of hard coal and lignite was found to be the major emission source of mercury into the atmosphere.

Emission factor of mercury from coal-fired power stations.

Mercury emission from coal-fired power stations, situated in Poland in the Silesian region was investigated. The determination methods for mercury in the consumed coal and in combustion gas, used in this research, are described. The mass of mercury emitted into the air from coal combustion in the power station is in constant relation to the mercury content in the consumed coal during the assumed period. A relationship between mercury emission into the air and the mercury content in the consumed coal in electric power stations is derived.

Determination of elemental carbon emission.

The studies on elemental carbon content in the atmospheric air, performed at the air monitoring station in Katowice (Poland), have revealed violations of allowable maximum average annual and diurnal concentrations. Elemental carbon is introduced into the atmosphere mainly as soot generated from combustion processes. This work presents the determination of elemental carbon in emission generated from coal combustion processes.

Methods for determination of elemental carbon in ambient air.

A few analytical methods of elemental carbon determination are described. The purpose of the work is to choose the best method for determination of its content in dust suspended in air in industrial regions. The reflectance and chromatographic methods were investigated. It was shown that the reflectance methods could be used only when the particle size and form of elemental carbons constant. The chromatographic method, which includes the step of combustion of the sample in oxygen and chromatographic determination of evolved CO2 is recommended, since it is independent of the form of carbon. Organic carbon is removed from dust samples by extraction with benzene-methanol mixture.