The organic micro-pollutants recently studied in the lake Leman waters and ecosystem are non-polar volatil substances and organochlorines like PCBs and DDT. The main volatil substances found are tetra- and trichloroethylene and 1,4 - dichlorobenzene. Concentration of this substances seems not ta be alarming. Pollution by DDT and its derivatives is decreasing, but the PCBs concentrations of coastal sediments and fishes can ta be considered as high and risk to produce a long-term contamination of the lake ecosystem. Eco-toxicological problems like a diminution of reproductive potential of the chars ("Salvelinus alpinus") would be related with the presence of organochlorine residues.

National audience

International audience | The organic micro-pollutants recently studied in the lake Leman waters and ecosystem are non-polar volatil substances and organochlorines like PCBs and DDT. The main volatil substances found are tetra- and trichloroethylene and 1,4 - dichlorobenzene. Concentration of this substances seems not ta be alarming. Pollution by DDT and its derivatives is decreasing, but the PCBs concentrations of coastal sediments and fishes can ta be considered as high and risk to produce a long-term contamination of the lake ecosystem. Eco-toxicological problems like a diminution of reproductive potential of the chars ("Salvelinus alpinus") would be related with the presence of organochlorine residues.

Taenia saginata and other pathogens likely to cause problems resulting from agricultural use of sewage sludge, laboratory and field trials testing efficacy of DF 955 (formalin based compound) as a means of chemical destruction

Taenia saginata, Ascaris suum, current research on inactivation of ova in sewage sludge by means of heated anaerobic digestion: United Kingdom