A Large-Scale Identification of Sediment-Associated Risks of Contamination with Heavy Metals and Organics: Indicators and Algorithms


As mediators in key biotransformation processes, the complex enzyme activities (measured as a total of extracellular and intracellular activity on sub-organism, organism and supra-organism level) have a high potential to be used as reliable indicators for risk identification in co-contaminated sediments with organics and heavy metals. Two enzyme activities—dehydrogenase activity (TTC-DHA) and phosphatase activity index (PAI) were measured by use of methods with tetrazolium chloride and p-nitrophenyl phosphate in polluted sediments of Middle Iskar River part, Bulgaria. The environmental state of river sector has been strongly influenced by the organics, nutrients, xenobiotics pollutants and by the intensive hydrotechnical activity for construction of 9 micro-hydro power plants. The change of hydrological regime was a factor for intensive sediment accumulation and concentration of pollutants in the area of the cascade. Data for total activities of dehydrogenases and phosphatases in sediments were compared with total count of culturable sediment bacteria and pollutants concentrations. The results showed that the enzyme activities correlated positively with bacterial abundance in sediments and organics content in sediments and negatively with concentrations of xenobiotic pollutants (heavy metals). This approves a high potential of enzyme indicators for regulation of ecosystem self-purification capacity and for early assessment of sediment-associated risks of co-contamination. The correlative relations allow dividing the mathematical algorithms for control and management of processes in technologically influenced hydroecosystem.

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Todorova, Y. , Yotinov, I. , Lincheva, S. and Topalova, Y. (2015) A Large-Scale Identification of Sediment-Associated Risks of Contamination with Heavy Metals and Organics: Indicators and Algorithms. Journal of Water Resource and Protection, 7, 101-110. doi: 10.4236/jwarp.2015.72008.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Santos, B.J.C., Beltran, R. and Gomez, A.J.L. (2003) Spatial Variations of Heavy Metals Contamination in Sediments from Odiel River (Southwest Spain). Environment International, 29, 69-77.
[2] Zhu, H., Yuan, X., Zeng, G., Jiang, M., Liang, J., Zhang, C., Yin, J., Huang, H., Liu, Z. and Jiang, H. (2012) Ecological Risk Assessment of Heavy Metals in Sediments of Xiawan Port Based on Modified Potential Ecological Risk Index. Transactions of Nonferrous Metals Society of China, 22, 1470-1477.
[3] Hu, W.F., Lo, W., Chua, H., Sin, S.N. and Yu, P.H.F. (2001) Nutrient Release and Sediment Oxygen Demand in a Eutrophic Land-Locked Embayment in Hong Kong. Environment International, 26, 369-375.
[4] Petticrew, E.L. and Arocena, J.M. (2001) Evaluation of Iron-Phosphate as a Source of Internal Lake Phosphorus Loading. Science of the Total Environment, 266, 87-93.
[5] Mihailova, P., Traykov, I., Tosheva, A. and Nachev, M. (2013) Changes in Biological and Physicochemical Parameters of River Water in a Small Hydropower Reservoir Cascade. Bulgarian Journal of Agricultural Science, 19, 286-289.
[6] Yotinov, I., Lincheva, S., Kenderov, L., Schneider, I. and Topalova, Y. (2013) Evaluation of the Self-Purification in the Waters of the Micro-Dams in the Small Hydroelectric Power Plants (HEPPs) Lakatnik and Svrazhen: Potential of the Bioalgorithms. Bulgarian Journal of Agricultural Science, 19, 135-139.
[7] Todorova, Y. and Topalova, Y. (2013) Short-Time Effect of Heavy Metals Stress on Key Enzyme Indicators in River Sediments. Bulgarian Journal of Agricultural Science, 19, 282-285.
[8] Todorova, Y. and Topalova, Y. (2010) Modulation Effect of Heavy Metal Pollution on Key Enzyme Activities in River Sediments. Journal of Biotechnology, 150, 283-284.
[9] Lincheva, S., Todorova, Y. and Topalova Y. (2014) Long-Term Assessment of the Self-Purification Potential of a Technologically Managed Ecosystem: The Middle Iskar Cascade. Biotechnology and Biotechnological Equipment, 28, 455-462.
[10] Vidali, M. (2001) Bioremediation. An Overview. Pure Applied Chemistry, 73, 1163-1172.
[11] Tabak, H.H., Lens, P., van Hullebusch, E.D. and Dejonghe, W. (2005) Developments in Bioremediation of Soils and Sediments Polluted with Metals and Radionuclides-1. Microbial Processes and Mechanisms Affecting Bioremediation of Metal Contamination and Influencing Metal Toxicity and Transport. Reviews in Environmental Science and Bio/ Technology, 4, 115-156.
[12] Perelo, L.W. (2010) Review: In Situ Bioremediation of Organic Pollutants in Aquatic Sediments. Journal of Hazardous Materials, 177, 81-89.
[13] Topalova, Y. (2009) Biological Control and Management of Wastewater Treatment. Publish ScieSet-Eco, Sofia.
[14] Arnosti, C. (2003) Microbial Extracellular Enzymes and Their Role in Dissolved Organic Matter Cycling. In: Sinsabaugh, R.L., Ed., Aquatic Ecosystems: Interactivity of Dissolved Organic Matter, Academic Press, San Diego, 315-342.
[15] Chrost, R.J. and Siuda, W. (2002) Ecology of Microbial Enzymes in Lake Ecosystems. In: Burns, R.C. and Dick, R.P., Eds., Microbial Enzymes in the Environment Activity, Ecology, and Applications, Marcel Dekker, Inc., New York, 35-72.
[16] Chrost, R.J. (1992) Significance of Bacterial Ectoenzymes in Aquatic Environments. Hydrobiologia, 243-244, 61-70.
[17] Wlodarczyk, T. (2000) Some of Aspects of Dehydrogenase Activity in Soils. International Agrophysics, 14, 365-376.
[18] Wilczek, S., Fischer, H. and Pusch, M. (2005) Regulation and Seasonal Dynamics of Extracellular Enzyme Activities in the Sediments of a Large Lowland River. Microbial Ecology, 50, 253-267.
[19] Matavuly, M., Bokorov, M., Gayin, S., Gantar, M., Stoyilkovicy, S. and Flint, K.P. (1990) Phosphatase Activity of Water as a Monitoring Parameter. Water Science and Technology, 2, 63-68.
[20] Kenderov, L. and Yaneva, I. (2009) Ecological Characteristics of the Iskar River Catchment. Biotechnology and Biotechnological Equipment, 23, 276-280.
[21] APHA, AWWA and WEF (1989) Standard Methods for the Examination of Water and Wastewater. Washington DC.
[22] Lenhard, G., Nourse, L.D. and Schwartz, H.M. (1964) The Measurement of Dehydrogenase Activity of Activated Sludge. Advances in Water Pollution, 2, 105-107.
[23] Kochetov, G.A. (1980) A Practical Guide on Enzymology. High School, Moscow.
[24] EUR-Lex (2000) Directive 2000/60/EC of the European Parliament and of the Council Establishing a Framework for Community Action in the Field of Water Policy.
[25] Alexander, M. (1994) Biodegradation and Bioremediation. Academic Press, San Diego.
[26] Lacerda, L.D., Fernandez, M.A., Calazans, C.F. and Tanizaki, K.F. (1992) Bioavailability of Heavy Metals in Sediments of Two Coastal Lagoons in Rio de Janeiro, Brazil. Hydrobiologia, 228, 65-70.
[27] Bryan, G.W. and Langston, W.J. (1992) Bioavailability, Accumulation and Effects of Heavy Metals in Sediments with Special Reference to United Kingdom Estuaries: A Review. Environmental Pollution, 76, 89-131.
[28] US-EPA (2002) A Guidance Manual to Support the Assessment of Contaminated Sediments in Freshwater Ecosystems. Volume III—Interpretation of the Results of Sediment Quality Investigations. Washington DC.
[29] Lorenz, N., Hintemann, T., Kramarewa, T., Katayama, A., Yasuta, T., Marschner, P. and Kandeler, E. (2006) Response of Microbial Activity and Microbial Community Composition in Soils to Long-Term Arsenic and Cadmium Exposure. Soil Biology & Biochemistry, 38, 1430-1437.
[30] Chaperon, S. and Sauve, S. (2007) Toxicity Interaction of Metals (Ag, Cu, Hg, Zn) to Urease and Dehydrogenase Activities in Soils. Soil Biology & Biochemistry, 39, 2329-2338.
[31] Xie, W., Zhou, J., Wangb, H., Chen, X., Lu, Z., Yu, J. and Chen, X. (2009) Short-Term Effects of Copper, Cadmium and Cypermethrin on Dehydrogenase Activity and Microbial Functional Diversity in Soils after Long-Term Mineral or Organic Fertilization. Agriculture, Ecosystems and Environment, 129, 450-456.
[32] Cerón, L.E.R. and Ramírez, E.V. (2011) Microbial Activity in Soil and Sediments of the Upper Arzobispo River Basin. Agronomía Colombiana, 29, 257-263.
[33] Khan, S., Cao, Q., Hesham, A., Xia, Y. and He, J. (2007) Soil Enzymatic Activities and Microbial Community Structure with Different Application Rates of Cd and Pb. Journal of Environmental Sciences, 19, 834-840.

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