ISSN:
1440-1770
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Geography
Notes:
The water quality of Lake Orta was evaluated for recreational use. This lake was the only Italian lake to undergo a ‘liming treatment’ which neutralizes water acidity by adding carbonates. Chemical, bacteriological and virological parameters were monitored for 3 years after the treatment ended. Chemical and bacteriological studies were performed according to national standard methods (DPR 470/82) whereas F′ specific bacteriophage were enumerated according to an international standard (ISO 10705–1). Enteroviruses were detected by the observation of a cytophatic effect on buffalo green monkey cultures. Also, the possibility of applying molecular biological techniques for enterovirus detection directly to waters concentrated without previous isolation of viruses in cell culture was verified. The sensitivity, specificity and feasibility of both methods were evaluated. The association between the direct detection of enteroviruses and the indirect indication of their presence by the presence of bacteriophages, and the relationship between bacteriophage presence and bacteriological contamination were also evaluated. In the course of surveillance, none of the samples infringed the law with respect to the physical–chemical parameter (pH 〈 6). As far as bacteriological characteristics were concerned, 16.6% of the samples taken in 1993 infringed the law, as well as 19.4% of samples in 1994 and 19.4% in 1995. The level of faecal coliforms most frequently exceeded the given limits. The detection test for enteroviruses was positive in 5.1% of the samples using the traditional method with cell culture, and it was positive in 7.6% using the antigen capture polymerase chain reaction (AC-PCR) method directly applied to concentrated waters, indicating the feasibility and a higher sensitivity of the AC-PCR method compared to cell culture. Bacteriophages were present in all the samples that were positive in the virological analysis, as well as in 46.7% of negative samples.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1440-1770.1999.00083.x
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