Spatial Distribution of PCDD/F in Surface Sediments of Lake Maggiore (Italy)

2 . As a consequence the local Health Authorities prohibited commercial fishing of a series of contaminated fish species. The source of DDT contamination was a DDT production site, closed down in 1996. This plant was located on the Marmazza River, a tributary of River Toce entering LM from the westernmost part of LM, close to Baveno. Besides the contamination with DDT, PCBs, including some dioxin like congeners, were found at concentrations exceeding 3-7 times the levels of other sub alpine lakes in Italy. Levels of HCB and HCH in the LM ecosystem instead gave no rise to concern 1 . The aim of the present study is to supplement the existing data on POPs with sediment levels of PCDD/Fs, where so far only few data 3 are available for LM. Materials and Methods