[Lead poisoning in Norwegian waterfowl (author's transl)]

In connection with routine autopsy of wild birds, liver samples from 56 waterfowl, representing 12 species, were analyzed for the content of lead. The median value for the birds examined was 0.2 microgram Pb/g wet weight. Concentrations probably causing lead poisoning were found in 1 mallard (Anas platyrhychos) with 11 microgram Pb/g liver and in 8 whooper swans (Cygnus cygnus) with 5.8--55 microgram Pb/g liver. Clinical observations and pathological findings of "typical" lead poisoning were found in 2 of the whooper swans with 25 and 55 microgram Pb/g liver, respectively. Lead was not detected (less than 0.1 microgram Pb/g liver) in 29% of the 34 whooper swans examined, while another 29% contained more than 1.0 microgram Pb/g liver. In some swans with a low liver lead concentration the autopsy findings strongly indicated an intoxication. The necessity of chemical analyses for the verification of lead poisoning is emphasized. The limited number of birds examined and the uneven selection among species prevent the drawing of general conclusions. This investigation indicates, however, that lead poisoning, especially in the whooper swan, may be a problem also in Norway, but hardly a so important one as in some other European countries and in the USA.