IDENTIFICATION AND LEVEL ESTIMATION OF CHLORINATED NEUTRAL AROMATIC SULFUR-COMPOUNDS AND THEIR ALKYLATED DERIVATIVES IN PULP-MILL EFFLUENTSAND SEDIMENTS

Seven effluent samples from a modern pulp mill, in which chlorine and chlorine dioxide bleaching is used, and five sediment samples from the recipient watercourse were investigated for polychlorinated dibenzoth iophenes (PCDBTs), polychlorinated thianthrenes (PCTAs), polychlorinat ed diphenylsulfides (PCDPSs) and for alkylated derivatives of these. M ainly di-, tri-, tetra- and pentachlorinated congeners were studied. P articles and filtrates from the effluents were analyzed separately. Th e concentration levels of the nonalkylated compounds were found to be higher in the filtrates than in the particles. Trichlorinated dibenzot hiophenes and thianthrenes were found as the major congeners. Pentachl orinated derivatives were not found. Alkylated di- and trichlorodibenz othiophenes were detected in some samples, while alkylated chlorinated thianthrenes and diphenylsulfides were nondetectable. The estimated c oncentration levels of the compounds detected were in the range of 40- 2700 pg/L in the pulp mill effluents and in the range of 2-40 pg/g dry weight in the sediments. Mixtures of methylated di- and trichlorodibe nzothiophenes used as references in analyses were prepared from methyl chlorobiphenyls. Some new pure model compounds were obtained by HPLC f ractionation of the chlorination mixture of dibenzothiophene. Structur es of these were determined by H-1 NMR.