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Digested sludge samples from domestic wastewater treatment plants located in Northern Italy were tested as far as the presence of viruses (enteric viruses and coliphages), bacteria (faecal coliforms, salmonella) and helminth eggs is concerned. Heavy metals were also analysed. Escherichia coli bacteriophages and faecal coliforms were isolated from all samples, while salmonellae and helminth eggs were isolated only from four and three out of 27 total samples, respectively. The 66% of sludge samples, 46 and 82% of aerobic and anaerobic digested sludges respectively, showed the presence of enteric viruses (enteroviruses and reoviruses). The virus concentrations ranged from 0.6 to 123 MPNCU/g. Results of this study suggest that significant concentrations of pathogens such as enteric viruses can be present in digested sludge, which showed compliance with Italian legislation. As suggested by other authors, there is the need for surveillance and reference indications both in EU (European Union) and Italian regulations concerning the use of sludge in agriculture. [ABSTRACT FROM AUTHOR]

Monitoring was carried out during summer 1997 along a selected area of the Tyrrhenian coast near the Tiber river mouth. Fifty-eight seawater samples, collected from 19 stations, were examined for coliforms, streptococci, Enteroviruses, Salmonellae, coliphages, Bacteroides fragilis phages, Pseudomonas, alophilic Vibrios, Aeromonas and yeasts. Salmonellae and coliphages were isolated in 3 and 12 out of 58 samples, respectively. Enteroviruses and Bacteroides fragilis phages were not isolated. Reoviruses were isolated only from 2 out of 58 samples. A limited number of samples of the northern stations located near the Tiber and other river mouths exceeded the guide values for bathing water by the EU Directive. All the southern stations, located near canals, were of very good microbiological quality. Pseudomonas, Vibrio, Aeromonas and yeasts were isolated from all stations and their values in 100 ml of seawater were 10-10[sup 6], 10-10[sup 6], 0-10[sup 6] and 1-10[sup 3], respectively. An extensive disinfection practice carried out on domestic wastes, which are discharged in rivers and canals, probably brought pollution levels of most stations to values within the bacterial standards. The spread of Pseudomonas, Aeromonas, etc. showed that all the coastal area studied was characterized by the presence of organic matter coming from land that can support the presence of opportunistic pathogens and other microbial flora. [ABSTRACT FROM AUTHOR]