On the determination of subpicogram concentrations of Pu in environment and living species

The method of ²³⁹Pu minor content determination based on subsequent activation with thermal neutrons and gamma-rays was applied for preparations chemically separated from soils, water, river sediments and some living species. The obtained level of sensitivity for routine analysis is proved to be equal 10⁻¹³ gram Pu per gram of sample.