Nanoparticles are capable of preconcentrating various elements, including toxic ones; they have high mobility in the environment and can easily penetrate into a human body. The study of the chemical composition and properties of road dust nanoparticles is an urgent task of analytical chemistry, which needs to be addressed in the monitoring of the anthropogenic load on the environment and the assessment of the potential danger of pollution to human health. In the present paper, we propose a new approach for the isolation, characterization, and quantitative elemental analysis of road dust nanoparticles. Conditions are selected for the separation of nanoparticles from Moscow dust samples by field-flow fractionation in a rotating coiled column; the resulting fractions are characterized by independent methods (using static light scattering and electron microscopy); the method for calculating the concentration of elements in the nanoparticle fraction according to inductively coupled plasma atomic emission spectrometry and mass spectrometry is improved; elements in a water-soluble form are isolated and determined; and the role of soluble organic matter in the binding of trace elements is discussed. It is shown that the total concentration of most elements in the samples of Moscow dust is comparable to the average values for urban soils. Abnormally high concentrations of several elements (Cu, Zn, Ag, Cd, Sn, Sb, Hg, Pb, Tl, and Bi) are revealed in the fraction of nanoparticles; the enrichment factor with respect to the total concentration ranges from 10 to 450. The source of contamination of road dust nanoparticles with copper, zinc, antimony, and cadmium is highly probable wearing-off of brake pads and car tires. The developed procedure of separation, characterization, and analysis of nanoparticles can be used for other polydisperse environmental samples (for example, volcanic ash).

State-of-the-art approaches to the study of environmental natural and man-made nano- and microparticles are summarized. Separation methods (sedimentation, membrane filtration, field-flow fractionation), methods for assessing particle size and morphology (electron microscopy, dynamic and static light scattering), and also methods for their elemental analysis (inductively coupled plasma atomic emission and mass spectrometry, atomic absorption spectrometry, energy-dispersive X-ray spectroscopy) are considered. Some particular examples of studies of natural particles of dust, volcanic ash, and natural waters, and also of synthetic nanoparticles of environment samples are presented. A necessity of using a complex of complementary methods of the separation, characterization, and analysis in the study of environmental particles is shown. Special attention is paid to hybrid methods ensuring the online separation, size evaluation, and analysis of particles. The main problems of the characterization and analysis of natural nanoparticles are formulated, and possible methods of their solution are proposed.