Simple coprecipitation method combined with low-background γ-spectrometry:: Determination of 7Be, 137CS, 210Pb, and radium and thorium isotopes in small-volume coastal water samples

Application of a coprecipitation method combined with low-background gamma-spectrometry allowed the isolation of Be-7, (CS)-C-137, Pb-210, and radium and thorium isotopes together with BaSO4, Fe(OH)(3), or AMP/Cs in 18 L of coastal water. This simple method showed high chemical yields of 77-91% (mean, 85%) for Pb-210 and radium isotopes, 87-92% (mean, 91%) for Be-7 and thorium isotopes, and 98% for (CS)-C-137. The activity of the nuclides showed good reproducibility with standard deviations of 1-8%, while the deviation of activity in particle-reactive Pb-210 (32%) and Be-7 (21%) in filtered water samples was exceptionally large.