A review of publications on the creation and application of certified reference materials for the chemical analysis of geological materials and environmental objects with the aim to ensure the uniformity of measurements is presented.

The role of plant-matrix certified reference materials as instruments ensuring the uniformity of measurements and the reliability of the results in performing ecological research and the production of foodstuffs and medicines is discussed. Specific features of the composition of plants as of test materials for chemical analysis and requirements to the methods of its determination are considered from the viewpoint of the provision of traditional agricultural tasks and geochemical, ecological, and medicobiological projects with certified reference materials. International and Russian regulatory documents on the preparation of certified reference materials taking into account the limited concentrations of toxic elements in plant materials are presented. Various content of classes of the existing plant-matrix certified, reference and for quality control materials of different producers are noted. The need in the expansion of the list of matrix certified reference materials for ensuring the reliability of analytical procedures in using methods of chemical analysis of plant materials and the consistency of their results is shown.

Plants of the genus Thymus L. are traditionally used in medicine and cooking due to the presence of biologically active compounds in them that have fungicidal, antibacterial and other medicinal properties and original taste qualities. Genetic features and growing conditions cause the elemental composition, responsibly of the synthesised medicinal compounds. However, information on the contents and distributions of elements in the organs of Thymus L. is very limited. This study was to set and compare the elements in organs of wild thyme for different soil and climatic conditions. Two species of wild Thymus L. from Mongolian steppe and on the coast of Lake Baikal were collected during flowering. Twenty-four elements, including Si, in soils, roots, stems, leaves and flowers were simultaneously determined by atomic emission spectrometry. Elemental profiles of two species of wild Thymus L. are described. It is assumed that Si is a necessary element of the plant. The predominance of the genetic resistance of plants over the influence of soil and climatic conditions is shown.

The way of extraction of insoluble carbonaceous substance (ICS) from black shales and technique of determination of noble metals (NM) in it by direct arc atomic emission analysis (AEA) were developed. The first results are reported on the determination of mineral-bound noble metals in ICS concentrates, which were extracted from the rocks and ores of the Sukhoi Log, Vernyi, Vasil’evskoe, Kuranakh, Daugyztau, Bakyrchik, Kamennoe, El’dorado, and other deposits.

Scintillation arc atomic-emission spectrometry (SAES) is used to study noble metals (NM), including Au, Ag, Pt, Pd, Ir, Os, Rh, and Ru, in black shales of the Sukhoi Log gold deposit (Irkutsk Region, Russia), with a focus on NM total contents in samples and on the compositions and sizes of NM-bearing particles. The estimated sizes of gold particles and their distribution are confirmed by results of scanning electron microscopy combined with energy dispersive X-ray microanalysis (SEM-EDX). The SAES results are in satisfactory agreement with earlier SEM-EDX data on NM species but reveal a much greater number and diversity of element associations.

ОПРЕДЕЛЕНИЕ МИКРОЭЛЕМЕНТОВ В РАСТЕНИЯХ МЕТОДОМ ДУГОВОЙ АТОМНО-ЭМИССИОННОЙ СПЕКТРОМЕТРИИ