All samples were collected in June 2000. Two Scottish soils,
Cruden Bay (clay loam) and Glencorse (clay loam) were
used in this study. Soils were sampled from 0 to 25 cm
depth and homogenized by passage through a 3á35-mm
sieve. Samples of river water were obtained from the Rivers
Dee and Don in Aberdeen. Private drinking water was
obtained from a 10-m deep well on pasture grassland in rural
Aberdeenshire. Prior to use, all samples were stored at 4°C.
Unless otherwise stated, all soil data are presented on a dry
weight basis.