I. Juttner et al., OCCURRENCE OF PCDD F IN DATED LAKE-SEDIMENTS OF THE BLACK-FOREST, SOUTHWESTERN GERMANY/, Environmental science & technology, 31(3), 1997, pp. 806-812
Despite concerns about the toxicity of polychlorinated dibenmo-p-dioxi
ns and dibenzofurans (PCDD/F), there are still few data on their past
trends in Middle Europe. Here, We use paleolimnology to assess the occ
urrence of PCDD/F in sediments of four remote Black Forest lakes where
atmospheric deposition has been the only possible input. Considerable
quantities of PCDD/F occurred in the sediments of one lake before the
production of chlorophenols in the 1920s, emphasizing that they are n
ot only recent contaminants. On the basis of homologue profiles typica
l for soots, we suggest that fossil fuels burned since industrializati
on were a major source at this time. PCDD/F loadings in sediments acce
lerated in the 1930s at one site and in the 1960s at three others. Cha
nges in homologue profiles were lake-specific but generally implicated
sources in waste incineration, combustion of fossil fuels, and metal
processing. Peak TEQ of 205.2 and 228.7 ng/kg occurred respectively in
sediments from 1964 to 1985 at Wildsee and from 1982 to 1992 at Herre
nwieser See. Despite the small geographical area represented by the la
kes, their historical trends in PCDD/F burden differed due probably to
variations in local and regional sources. This indicates that more ex
tensive surveys than those often available are required to ensure repr
esentative data on regional patterns of contamination.