DETERMINATION OF POLYCHLORINATED DIBENZOTHIOPHENES IN STACK GASES AND IN BLEACHED PULP MILL EFFLUENTS

Abstract

Poiychlorinated dibenzothiophenes (PCDBTs) are environ- nnentaiiy interesting connpounds due to their structural resennbiance with poiychlorinated dibenzodioxins (PCDDs) and dibenzofurans (PCDFs), ^'^ The potential hazard of PCDBTs has been recently indicated by finding PCDBTs in emissions of waste incineration. ^'^ The origin of the PCDBTs in different environmental samples is not known. It is possible that these compounds are formed from polychlorobiphenyls and sulfur quite generally found in raw materials and chemicals or from different poiychlorinated thiophenols which are degradation products of certain pesticides and in part naturally occuring compounds through condensation reactions in a similar way as PCDFs are suggested to be formed from chlorophenols^. In