Mutagenicity of drinking water sampled from the Yangtze River and Hanshui River (Wuhan section) and correlations with water quality parameters

Abstract

A total of 54 water samples were collected during three different hydrologic periods (level period, wet period, and dry period) from Plant A and Plant B (a source for Yangtze River and Hanshui River water, respectively), and several water parameters, such as chemical oxygen demand (COD), turbidity, and total organic carbon (TOC), were simultaneously analyzed. The mutagenicity of the water samples was evaluated using the Ames test with Salmonella typhimurium strains TA98 and TA100. According to the results, the organic compounds in the water were largely frame-shift mutagens, as positive results were found for most of the tests using TA98. All of the finished water samples exhibited stronger mutagenicity than the relative raw and distribution water samples, with water samples collected from Plant B presenting stronger mutagenic strength than those from Plant A. The finished water samples from Plant A displayed a seasonal-dependent variation. Water parameters including COD (r = 0.599, P = 0.009), TOC (r = 0.681, P = 0.02), UV254 (r = 0.711, P = 0.001), and total nitrogen (r = 0.570, P = 0.014) exhibited good correlations with mutagenicity (TA98), at 2.0 L/plate, which bolsters the argument of the importance of using mutagenicity as a new parameter to assess the quality of drinking water.

Mutagenicity as a parameter in surface water monitoring programs—opportunity for water quality improvement

“…TA98 Salmonella strain was by far the most sensitive strain, 99% of the positive samples showed mutagenic activity with that strain, regardless the presence of metabolic activation, or positive results also detected with other strains. The same kind of results were observed by Kanno et al (2010), andLv et al (2015), and pointed out in the review by Ohe et al (2004), as well. In our study, positive results were detected with TA98 and not detected with TA100 (or YG1042, see below) in 234 samples, of which 83 were positive with and without metabolic activation (24% of all positive samples), 113 exclusively without S9, and 38 exclusively with S9 (32% and 11% of all mutagenic samples, respectively).…”

The mutagenicity of organic extracts in source water and peripheral water with different disinfection ways

“…Some studies have indicated mutagenic potential of drinking water. For instance, all water extracts from the Yangtze River and Hanshui River caused dose-dependent DNA mutation at certain concentrations, and mutagenicity varied during different seasons (Liu et al, 2011;Wu et al, 2004;Yuan et al, 2005 typhimurium strains TA98 and TA100 (Lv et al, 2015). It was found that the organic compounds in the water were largely frame-shift mutagens, and the finished water samples exhibited stronger mutagenicity than the relative raw and distribution water samples.…”

Application ofin vitrobioassays for water quality monitoring in three drinking water treatment plants using different treatment processes including biological treatment, nanofiltration and ozonation coupled with disinfection

“…In contrast, mutagenicity and adaptive stress responses, such as the oxidative stress response, often increase after drinking water treatment. 10,12,15,16 This is attributed to the formation of disinfection by-products (DBPs) from the reaction of disinfectants, such as chlorine, with natural organic matter and inorganic ions, such as bromide and iodide. 17 Unlike chemical analysis, which provides information about the individual chemicals present in a sample, bioassays respond to all active chemicals and cannot distinguish between micropollutants and DBPs.…”