Data comprise concentration ratios for lead and 210Pb in terrestrial wildlife and plants, and residual maximum likelihood (REML) model values for taxons (order, family and genus). Pb was used as an example of the derivation and application of a REML model for terrestrial wildlife species. The model outputs consists of a mean value for each taxa on a common scale after REML adjustment (referred to as the ‘REML mean’) taking account of the random factor (i.e. site). The REML mean value represents a relative scaling value. Funding for preparing this data set was provided by the TREE project (http://www.ceh.ac.uk/tree) funded by the NERC, the Environment Agency and Radioactive Waste Management Ltd. under the RATE programme. Full details about this dataset can be found at https://doi.org/10.5285/2bd9bd0e-2c52-4767-ae2e-9c70ba8c358d