Virus detection in drinking water is very important to protect human health. The different methodologies for analysing human pathogenic virus are very time consuming and expensive, so until now only a few specialised laboratories carried out this analysis. Detection of bacteriophages may be possible by examining the aquatic virus, with advantages of easy and cheap. The bacteriophages ofBacteroides fragilis have been proven as specifically present in human faeces and have relationships with water contaminated by enterovirus. Our study, for the first time in France, discovered theB. fragilis phages present in sample of sewage, Seine river and raw water for water supply. Our results also presented thatB. fragilis phages may be a better indicator for water bacteriology compared with classical bacteriological indicators in water treatment. On the other hand, our results demonstrated that MPN method (Most Probable Number) has more advantages than that of PFU (Plaque Forming Units).

The equilibrium partitioning theory may be used to describe the partitioning of nonionic organic chemicals between water, sediment, and aquatic biota. This paradigm was employed to compare the relative magnitudes of organic carbon-normalized sediment-quality criteria that are intended to protect either benthic organisms from the direct toxic effects of sediment-associated chemicals or humans from the indirect health effects posed by the ingestion of contaminated aquatic animals. Comparison of calculated sediment-quality criteria for a variety of hydrophobic chemicals suggests that human health-based end points often result in more restrictive criteria than aquatic effects-based values. Review of published field data indicates that the equilibrium partitioning paradigm may, depending on contaminant class, either over- or underestimate the extent to which sediment-associated contaminations are bioaccumulated. Despite the limitations of adopting this simple theory for criteria development, calculations reveal that regulatory decisions involving sediments contaminated with such chemicals may be dictated by human health concerns if current risk assessment methodologies are applied.