International Science-Technology Center (ISTC) project KR-964, 2004-2006, PI: Perminova I.V.

Development of detoxicants of combined action on the basis of humic substances and their derivatives

Leading Institution:

• Institute of Chemistry and Chemical Technology of NAS, KR

Participating Institutions:

• Chemical Faculty of Lomonosov's Moscow State University
• Open Joint Stock Company "Biochimmash"

Foreign Collaborators/Partners:

• Institute for Ecological Chemistry, the Research Center for Environment and Health (IOEC GSF)

SUMMARY

Chemical pollution threatens greatly natural environments and can lead to the complete destruction of biogenosis. Effective detoxification of the contaminated environments is a primary condition for successful rehabilitation of the damaged biogenosis. The success of detoxification depends greatly on the efficiency of the detoxicants used. The latter is determined by the binding affinity of detoxicants for heavy metals and organic xenobiotica. The detoxifying effects can be substantially strengthen if the detoxicants are able of adaptogenic activity displayed as an increase in resistance of living organisms to chemical stress.

Humic substances (HS) and their derivatives can be considered as very promising compounds for development of the detoxicants of the wanted combined action. HS possess the properties of soil amendments, sorbents and antidotes. They do not expose toxic effects on biota. On contrary, HS are known to act as natural adaptogens increasing the resistance of living organisms to non-specific stress factors. For industrial applications, of particular importance is an ease of modification of HS and tremendous resources of the raw humic materials (brown coal, peat, and sapropel). Chemical and microbiological techniques can be applied for designing HS-based products of the wanted properties. They can be enriched with ionogenic groups, chelating fragments or hydrophobic units. Depending on the kind of modification, the obtained humic detoxicants can act as chelating agents, redox mediators, sorbents or flushing agents. Development of the HS based products of the controlled properties is a prerequisite for their wide use in remediation technologies.

The goal of the project is to develop detoxicants of combined action on the basis of humic substances and their derivatives and to optimize the technology for their production.

To reach the goal, the following objectives are set:

• to obtain humic preparations enriched with ionogenic groups, chelating fragments and hydrophobic units using techniques of fractionation and chemical and microbiological modification;
• to characterize structure and binding properties of the obtained humic preparations with respect to heavy metals and priority organic contaminants;
• to evaluate safety and adaptogenic activity of the obtained humic preparations using bioassays;
• to evaluate detoxifying properties of the humic preparations obtained with respect to priority classes of ecotoxicants using bioassays and vegetation experiments;
• to scale-up technology for production of the humic preparations that showed the highest detoxidying efficiency and specificity in the lab experiments;
• to assemble the technological lines for production of the most efficient humic detoxicants including different commercial forms (powder, granulate, solution) designed for different applications;
• to conduct field experiments on detoxification of contaminated territories using the humic detoxicants produced.

Novelty of the proposed research is provided by a lack of the reported developments both on the laboratory synthesis and industrial production of the humic detoxicants of the controlled properties. A use of humic derivatives along with the bulk humates is particularly promising. For the first time, the directed modification will be carried out in accordance with the preliminary derived "structure- detoxifying property" relationships to obtain humic preparations of the wanted properties. Production of the large quantities of the non-specific and selective humic detoxicants will allow unique investigations on the field-scale. Realization of the proposed research can promote greatly application of humic preparations in practice of remediation technologies.