HL Deb 29 October 1981 vol 424 c1191WA
Lord Melchett

asked Her Majesty's Government:

Whether they will confirm that there has been no significant drop in the levels of DDE (the main metabolite of DDT) in sparrowhawks and kestrels in the last 10 years.

Earl Ferrers

Available data, notably from the Institute of Terrestrial Ecology and my department's science laboratories, do not provide a basis for any reliable conclusions. In particular, and until recently, the data related mainly to birds which happen to have died for whatever reason and had been supplied or obtained for laboratory examination. Within the available samples, which are not necessarily representative, the indications are that DDE residues may have declined in kestrels over the past decade, but not in sparrowhawks. Current studies are designed in order to provide wider and more reliable data including, incidentally, DDE residues in birds upon which these two species prey and which migrate to the United Kingdom from countries which make more extensive use of pesticides containing DDT.