Quantification of umu genotoxicity level of urban river water

Abstract

In recent years, the request of environmental safety management for carcinogenic substances, mutagenic substances and/or reproductive toxicity substances (CMR) has increased. This study focused on clarifying the genotoxicity level of environmental water and its release source by using the umu test provided in ISO13829. Although a genotoxicity index "induction ratio (IR)" is used in ISO13829, we normalised it to make it possible to compare various environmental water quantitatively to each other as a new index "genotoxic activity (GA=(IR-1)/Dose)". Sample water was collected and concentrated to 100 times or 1,000 times by a solid phase extraction method. As the test results, it was found that GA level in actual river water varied widely from less than the determination limit of 23 [1/L] to 1,100 [1/L] by quantitative comparison, and the value was also equivalent to more than 50 times the level of tap water. The GA level of household wastewater was not so high, but the levels of treated water from wastewater treatment plant (WTP) were from 220 [1/L] to 3,200 [1/L]. Raw sewage of some WTP shows high level genotoxicity. A part of genotoxicity substances, for example 50%, could be removed by conventional wastewater treatment, but it was not enough to reduce the water environmental load of genotoxicity.

Seasonal Fluctuation of Polycyclic Aromatic Hydrocarbons and Aerosol Genotoxicity in Long-Range Transported Air Mass Observed at the Western End of Japan

“…The slope of the regression line was defined as genotoxicity. To correct for variations in the test sensitivity, genotoxicity was divided by the results of the positive control tests and represented as positive control equivalents, as previously reported [67,68].…”

Genotoxicity of Water Extracts from Sewage Effluents in the Kanagawa Prefecture, Japan Using the Novel <i>umu</i> Tester Strain

“…Our research groups have previously evaluated the effectiveness of this strain for the detection of photo-induced genotoxicity of several compounds. Despite the numerous studies on river water drainage, there have been relatively few reports of the genotoxic effects of river water [20] (Kameya et al, 2011). In our study, we evaluated 60 points from 20 rivers located in the Sagami Bay area.…”

Quantitative Evaluation of the Genotoxic Activity of Japanese Tap Water Using the Umu Test

“…A microplate version of the umu test was also developed for rapid detection of the genotoxicity of environmental samples (Reifferscheid et al, 1991). This method was accepted as the international standard method ISO 13829 "Water quality -Determination of the genotoxicity of water and waste water using the umu-test" in 2000 (ISO, 2000) and has been used in many investigations (Castillo et al, 2001;Dizer et al, 2002;Xiao et al, 2006;Kameya et al, 2011). For example, Sugimura et al (2008) developed a quantification method and a concentration method for water samples and used them to report quantitative genotoxicity for several kinds of water samples.…”