Assessing water contamination
One of the popular methods of assessment of water contamination is monitoring and bio-indication of phytoplankton species quantity and diversity. Laboratory experiments on raw oil show differences in sensitive for a range of phytoplankton species. The species Ditylum brightwelli, Coscinodiscus granii and Chactoceros curvisetus perish within 24 h after oil treatment in 100 mcl/l concentration (Mironov, 1970). Experiments show delay of reproduction of phytoplankton species Nitzschia closterium with oil concentrations of 25% (Galtsoff et al., 1935). Other experiments show gathering of large numbers of active forms of Infusoria around an oil spot.
We carried out laboratory experiments on aquarium fish (Lebistes reticulates). They were kept in an oil polluted environment. Two aromatic fractions of Mirzaani oil showed mutagenic effect in chronic tests. The level of chromosomal aberrations was increased to 7-8% per cell compared with control cells (0.2%). The same experiments were carried out on laboratory mice, where aromatic fractions of oil were shown to have a mutagenic effect (Devidze, 1986).
The second part of our methodology for emergency response on oil spills is bioremediation, as a natural process that uses microorganisms to transform harmful substances into non-toxic carbon dioxide, water and fatty acids. We studied the microbial diversity of Cyanobacterial species in the mountain mineral waters of the Borjomi region, which is crossed by the pipeline. Phormidium, Oscillatoria, Mycrocystis, Gloeocapsa, and Synecho-cystis cyanobacterial morphotypes were dominant in this area. Laboratory research showed that in oil-contaminated cultures cyanobacterial communities of Phormidium tenuissimum, Synechocystis minuscula and Synechococcus elongates are edificatory. In small compounds of these communities, physiological groups of microorganisms are present that activate the process of degradation of the hydrocarbon components.
From the northern Caspian was picked out cyanobacterial community Phormidium gelatinosum Ph. tenue, Oscillatoria pseudogeminata, Osc. tambi, Osc. Amphibian (Soprunova, 2005). In our experiments it was shown that from these species the most resistant to oil contamination is Oscillatoria pseudogeminata as bacterial and fungi associates are present in its glico-calics and they are able to oxidize oil hydrocarbons.
Upon introduction into an oil spill contaminated environment, the microbes will germinate and become active instantly. In good conditions, these special microbial blends multiply exponentially within minutes. These begin the bioremediation to digest environmental pollution and wastes as long as all the necessary ingredients of water, oxygen and a food or waste source are present. Normal effective temperature range for these bio-remediation microbes is between 50°F to 100°F.
The underlying idea is to accelerate the rates of natural indigenous populations of microbial bacteria which can be stimulated through the addition of nutrients or other materials. Exogenous microbial populations can be introduced in the contaminated environment. But we do not recommend using exogenous microbial populations in sensitive areas as they will have negative impact on ecological balance in these ecosystems.
We recommend using indigenous Cyanobacteria compounds for sensitive area in the Borjomi region for remediation as emergency response to oil spills. It was shown that the introduction of Cyanobacteria associations in oil polluted ecosystems creates conditions for the development of polyfunctional associations (Cyanobacteria microalgae, bacteria, fungi), which degrade pollutants and increase the effective biological rehabilitation of contaminated areas.
In conclusion, our methodologies of bio-indication and defining Cyano-bacterial natural compound are being developed for bioremediation of oil contaminated waters, which will be used especially for sensitive areas as improved safety methods for emergency response for water security.
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