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At least 19 recordsLinked to original sources
PubMed1994

[Relationship between bacteria decomposing organic substances and water pollution in river water].

In order to clarify the relationship between water pollution and bacteria decomposing organic substances, 48 samples of river water were collected at twelve stations of the Chikuma-Sai river system. The bacteria decomposing organic substances were enumerated and identified by GM plates, which contained fewer organic substances than agar plates. Sixteen biological-physicochemical examinations of the river water were also performed. The results were as follows: temperature and dissolved oxygen in river water influenced the number of bacteria decomposing organic substances; proportions of bacteria decomposing degradable organic substances were higher in summer and spring than those in winter and autumn; the proportions of bacteria decomposing undegradable organic substances were higher in winter and autumn than those in other seasons. Organic substances were decomposed mainly by Aeromonas, a coliform group of facultatively anaerobic Gram-negative rods, and Pseudomonas, Gram-negative aerobic rods. Organic substances decomposed by facultatively anaerobic Gram-negative rods were much more degradable than those decomposed by Gram-negative aerobic rods. It seemed that the bacterial population of Aeromonas and the coliform group in river water increased with increases in the effluent of domestic and sewage abundant in degradable organic substances. Although Gram-positive rods were hardly isolated from river water, most of them decomposed undegradable organic substances. These results suggest that most bacteria decomposing organic substances are mainly distributed in river water and soil, and that modification of the river environment influences self-purification of rivers.

Bacteria↗
PubMed1982

Naegleria fowleri in thermally polluted waters).

Two complexes of lakes and canals supplying water for two electric power plants, their steam condensors and an adjoining river were investigated by means of culture methods for the presence of Naegleria fowleri in Poland in the period from 1974 to 1980. Sixty-four strains of N. fowleri were isolated, 13 isolates being virulent for mice when instilled intranasally. These strains were found in the steam condensor of the power station A and in waters polluted with warm water of this plant. Pathogenic N. fowleri strains occurred also in an adjoining river connected with the water system of the power plant. The results show the possible role of the steam condensor A as an incubator and regular source of pollution with pathogenic amoebae for its own system of cooling waters and even the adjoining river.

Amoeba↗
PubMed1992

[Nitrate water pollution of drinking water in the Bydgoszcz district].

The study was undertaken to evaluate the degree of drinking water pollution in the towns and countryside of the Bydgoszcz District, supplied by various installations, on the basis of the results of investigations of sanitary-epidemiological stations. Evaluation was done according to the state in 1985 as compared with that of 1981 to establish the eventual dynamics of the changes. The data presented in the tables indicate that the water supplied by the big water lines (public and institutional) does not contain nitrate quantities exceeding the norm (above 10 mg N/dm3). Their presence at a 20 mg N level/dm3 was found only in four (1.5%) lines supplying large state farms. Small installations were much more frequently polluted with nitrates, especially public wells and those of local institutions, a total of 8.8% in towns and as many as 17% in the country, where a tendency to deterioration of this state is also visible in contrast to the towns. Among the plants and institutions supplied by these water sources the situation is most unfavourable in agriculture, schools, educational and food producing and distributing establishments. The nitrate concentration in the analysed water varied in general within the limits of 10-30 mg N/dm3, maximal amounts within 60-200 mg N/dm3, showing an about 50% decrease in the compared time periods. Nitrates occur most frequently and in highest concentrations in water of wells belonging to individual households which supply about 50% of the rural population and about 11% of town dwellers.(ABSTRACT TRUNCATED AT 250 WORDS)

Nitrates↗
PubMed1993

[Relationship between water pollution and bacterial flora in river water].

To clarify the relationship between water pollution and bacterial flora in rivers, 132 samples of river water were collected at eleven stations of the Chikuma-Sai river system from April 1985 to March 1986, and 29 biological-physicochemical examinations for indices of water pollution were done using these samples. Species and genus of bacteria in 485 isolates from bacterial flora were identified. Although variations of bacterial flora were seen among sampling stations and sampling seasons, most isolated bacteria were Gram-negative (96.7-100%) with Pseudomonas (25.0-90.0%), Acinetobacter (0-43.8%) and Aeromonas (0-12.5%) occurring predominantly. The principal-component analysis of the data from water pollution indices indicated that the water pollution could be divided into two groups: One was categorized as organic pollution because of the strong relationship to the total plate count, the Bacillus number, coliforms, yeast and dissolved oxygen; the other as visible pollution because of strong relationship to transparency, chemical oxygen demand and suspended solids. Cluster analysis was applied to 19 indices of water pollution with strong relationships to the river pollution, indicating that five stages of river water pollution could be shown visually. The studies on the relationship between water pollution and bacterial flora in river showed that Pseudomonas, the coliform group, Pasteurella, Aeromonas, Acinetobacter, Achromobacter and Bacillus were strongly related to the organic pollution, and Flavobacterium, Moraxella and Pseudomonas (non-growth on MacConkey agar) to the visible pollution. It seemed that the more organic substances exceeded the capacity for self-purification of the river, the more the bacterial populations of Aeromonas, Pasteurella, Pseudomonas and the coliform group increased.

Bacteria↗