Occurrence of odor problems in drinking water of major cities across China

Abstract

A comprehensive investigation into the occurrence of odor problem at 111 drinking water treatment plants (DWTPs) in major cities across China was undertaken using both flavor profile analysis (FPA) and gas chromatography-mass spectrometry (GC-MS). Eighty percent of source water samples exhibited odor problems, characterized by earthy/musty (41%) and swampy/septic (36%) odors, while the occurrence rate was lower (45%) in the finished water. Source water from rivers exhibited more pollution-origin odors, such as the swampy/septic odor, while that from lakes and reservoirs exhibited more algaeorigin odors, such as earthy/musty odors. The occurrence rate of 2-methylisoborneol (2-MIB) in the surface source water samples was 75%, with 7% of samples containing 2-MIB concentrations of over 10 ng$L -1 . The earthy/musty odor in the lake/reservoir water samples was mainly caused by 2-MIB (linear regression coefficient, R 2 = 0.69), while the correlation between 2-MIB concentration and the earthy/musty odor intensity in the river-source water samples was weak (R 2 = 0.35). These results will be useful for the management of odor-quality problems in drinking water of China.

Simultaneous assessments of occurrence, ecological, human health, and organoleptic hazards for 77 VOCs in typical drinking water sources from 5 major river basins, China

“…Though MIB (FOD of 90%) was the most widely distributed odor-causing compounds, geosmin (FOD of 73%) was also frequently detected in this study. These results agree with others suggesting that MIB existed more widely than geosmin in source water of China (Sun et al, 2014). However, we found that the median and the mean concentrations of geosmin were higher than those of MIB, including several exceeding the reference values, but (Sun et al, 2014) detected the concentrations of geosmin lower than that of MIB.…”

“…These results agree with others suggesting that MIB existed more widely than geosmin in source water of China (Sun et al, 2014). However, we found that the median and the mean concentrations of geosmin were higher than those of MIB, including several exceeding the reference values, but (Sun et al, 2014) detected the concentrations of geosmin lower than that of MIB. Few studies have investigated the other 8 off-flavors in large scale (Chen et al, 2013a,b).…”

“…After that, related studies are focusing on ecological and human health risk assessments to evaluate the likelihood of adverse effects as a result of exposure to environmental contaminants (Du et al, 2013;Gao et al, 2012;Yang et al, 2014), especially the risks of natural water (Nganje et al, 2015;Zhu et al, 2015). What's more, concerns on taste and odor problems have been dramatically increased (Chen et al, 2013a,b;Sun et al, 2012Sun et al, , 2014Yu et al, 2009) since the water crisis in Wuxi, China in 2007 (Guo, 2007;Yang et al, 2008). These hazardous VOCs in water sources may not only affect the aquatic ecosystem, but also cause human health risks or taste and odor problems when they provide raw water for drinking water.…”

Simultaneous removal of multiple odorants from source water suffering from septic and musty odors: Verification in a full-scale water treatment plant with ozonation

“…Though reported less frequently, the septic odor caused by compounds such as thioethers and thiols is another important odor type because of its strong impact on human perception (Schiffman et al, 2001;Yang et al, 2008;Yu et al, 2009). These two types of odors have been those most frequently encountered in the source waters of China, according to a nationwide survey (Sun et al, 2014).…”

Source-water odor during winter in the Yellow River area of China: Occurrence and diagnosis

“…No fishy odor was perceived in the sample from Lanzhou, but a slightly septic/swampy odor was detected. A previous investigation on the occurrence of odor in major cities across China showed that river source waters tend to exhibit pollution-origin odors, while lake/reservoir source waters tend to exhibit algae-origin odors (Sun et al, 2014). Among the six cities, only Lanzhou takes water directly from the Yellow River without a reservoir, which might be the main reason for the lack of fishy odor in the source water.…”