It is presented results of research of molecular-mass distribution humic acids in peat soils dranned and used in agricultural production. The influence of the drainages on processes of organic matter transformations in upper layer dranned peat soil-unrepresentative for peat soils oxidation-reduction conditions and raised biological activity that is reflected on structure of humic acids.

Results obtained from comparative studies of the structures of humic acids from peats of different origins in the Tomsk area by infrared spectroscopy are presented. These data showed that the IR spectra of humic acids extracted from different types of peat had high levels of similarity, demonstrating similarities in their chemical structures. Humic acid from lowland woody-grassy peat had very significant differences from other types of peat and consisted of compounds with high proportions of aliphatic fragments and, perhaps, lower benzenoid levels, as well as higher contents of active acid groups (carboxyl, hydroxyl).

In article results of comparative studying of structure of humic acids of peats of a various origin of Tomsk area are resulted by a method of infra-red spectroscopy. It is shown, that IR-spectra of the humic acids taken from different types of peat, have a high degree of similarity that specifies affinity of their chemical structure. It is established, that humic acids low-moor woody-grassy type of peat have rather significant differences from other types of peat and represent connections with a high share aliphatic fragments and it is possible a smaller degree benzenoid, and also with the high contents of active sour groups (carboxylic, hydroxyl).

In article results of research of a chemical structure of humic acids of low-moor woody-grassy type of peat of Tomsk Region are resulted by methods of the elemental analysis and infra-red spectroscopy. In this work results of toxicological research of humic acids also are described: acute toxicity, pathomorphology and flow properties of blood. It is shown, that humic acids of low-moor woody-grassy type of peat represent connection with a high share aliphatic fragments submitted long connected by circuits, have a small degree benzenoid, contain active oxygen and itrogen-containing functional groups (carboxylic, hydroxyl, amides, amino groups). It is established, that humic acids at intragastric introduction are nontoxic substances. At intraperitoneal introduction of lethal dozes, the destruction of animals comes from acute intimate insufficiency, thus the cause of acute infringement hemodynamics can be negative influence of humic acids on flow properties of blood.

In the article results of research of a chemical structure of humic acids of low moor woody grassy type of peat of Tomsk area are resulted by methods of the elemental analysis and infra red spectroscopy. In this work results of toxicological research of humic acids also are described: acute toxicity, pathomorphology and flow properties of blood. It is shown, that humic acids of low moor woody grassy type of peat represent connection with a high share aliphatic fragments submitted long connected by circuits, have a small degree benzenoid, contain active oxygen and nitrogen containing functional groups (carboxylic, hydroxyl, amides, amino groups). It is established, that humic acids at intragastric introduction are nontoxic substances. At intraperitoneal introduction of lethal dozes the destruction of animals comes from acute intimate insufficiency, thus the cause of acute infringement hemodynamics can be negative influence of humic acids on flow properties of blood.

In given paper the results of comparative research of molecular parameters humic acids of various types of peat are resulted. As a method of research the method gel-chromatography is chosen. Results received during research have allowed to speak us about uniformity of molecules humic acids of various types of peat, however optimum for the further studying biological activity is chosen low tree-grassy peat since it is characterized by a set of more low-molecular humic acids.