Susceptibility of the eggs of the pest slug Deroceras reticulatum to contact with metal salts

Laboratory research is reported in which eggs of the pest slug Deroceras re ticulatum were incubated on filter paper moistened with solutions of cupric sulphate, aluminium sulphate, ferric chloride and zinc sulphate at differe nt concentrations. After four or more days exposure, the median lethal dose s (LD50) were below 10 mu g metal ion/cm(2) for the four metals tested. Cop per showed the highest toxicity with LD50 values below 5 mu g metal ion/cm( 2).