Biological Evaluation of Pollution in the Sagami River Using the 7-Ethoxycoumarin O-Deethylase Activity Induced by River Sediment Extracts in HepG2 Cells

Abstract

The arylhydrocarbon receptor (AhR)-dependent induction of 7-ethoxycoumarin O-deethylase (ECOD) activity in HepG2 cells was employed in a longitudinal study of pollution in the Sagami River flowing into Sagami Bay using river sediment extracts. The six sampling points for river sediment were Ogurabashi, Shimomizo, Atsugi, Kurami, Shinomiya, and Hiratsuka (in descending order of distance from the estuary). In samples obtained at the four midpoints along the river, ECOD activity was induced almost to the same extent. Ogurabashi, the point farthest from the estuary, seemed less polluted than downstream areas based on ECOD activity, while a marginal increase in the activity above the baseline was found at the highest concentration in the sample from Hiratsuka. The points where the river sediment caused a marked induction of ECOD activity in HepG2 cells were surrounded by inland industrial areas scattered along the river.

Bacterial community structure analysis of sediment in the Sagami River, Japan using a rapid approach based on two-dimensional DNA gel electrophoresis mapping with selective primer pairs

“…Because Lake Sagami located upstream of the river was found to be eutrophication and inland industrial areas are located midstream of the river, there may be pollution stresses on river sediments that accumulate pollutants. Although there were a few studies of chemical and biological evaluation on the river pollution (Iwashita and Shimamura 2003;Nito et al 2003), few analyses of bacterial community in the river sediments were found. In the present study, we attempted to analyze bacterial community structure in different sediments of the Sagami River using a rapid method on the basis of 2-DGE mapping combined with selective primer pairs, which can be used to match specific bacterial groups (Kang et al 2002).…”