POPs and organic polysufides in sediments of Lake Ladoga

Chemosphere. 2007 Mar;67(3):435-8. doi: 10.1016/j.chemosphere.2006.09.061. Epub 2006 Nov 30.

Abstract

The study included one station close to a pollution source (depth 59 m) and another far from polluted areas (depth 40 m). Samples were analysed for organic chlorine, bromine and sulfur compounds. Samples taken with a corer were sliced to the layers of 0-1, 1-4, 4-7 cm etc. down to the depth of 34 cm. The dating was made with two independent methods, the 210Po method and with the soot particle counting method. The analyses were made with a multiresidue method. Gas chromatography was connected to low resolution mass spectrometry (LRMS) or to high resolution mass spectrometry (HRMS). A different extraction was applied to screen the possible occurrence of polysulfides. Typical chlorophenol and chlorohydrocarbon traces from chlorobleaching of pulp were non-detectable. Also PCDDs, PCDFs, PCBs and various organochloride pesticides, fire retardant residues PBDEs, PBDDs and PBDFs and polychlorinated phenyl salicylates were not detected. Instead, methylated dibenzothiophenes Me-DBTs and Di-Me-DBTs, typical traces of oil based defoamers used in e.g. paper mills were found in the surface layers of the polluted site. Polysulfides were analyzed from layers representing years 1955-1970 from the polluted site. The structures of five congeners were according to GC/MS dimethyl trisulfide, 1,2,3,4-tetrathiepane, pentathiane, 1,2,3,4-tetrathiane and 1,2,4,5-tetrathiepane. Many of the analyzed pollutants have not been reported earlier from Lake Ladoga. The only positive observations were from oil-based defoamers used in paper mills, and from polysulfides, which are either of natural origin or indicate a discharge in the 1950s and 1960s. Owing to the large spreadout and dilution, the concentrations are low even at moderate distances from the pollution centers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chlorophenols / analysis
  • Finland
  • Fresh Water / chemistry*
  • Gas Chromatography-Mass Spectrometry
  • Geologic Sediments / chemistry*
  • Hydrocarbons, Brominated / analysis
  • Hydrocarbons, Chlorinated / analysis
  • Organic Chemicals / analysis*
  • Sulfides / analysis*
  • Thiophenes / analysis
  • Water Pollutants, Chemical / analysis*

Substances

  • Chlorophenols
  • Hydrocarbons, Brominated
  • Hydrocarbons, Chlorinated
  • Organic Chemicals
  • Sulfides
  • Thiophenes
  • Water Pollutants, Chemical
  • dibenzothiophene