Spectroscopic Indicators for Cytotoxicity of Chlorinated and Ozonated Effluents from Wastewater Stabilization Ponds and Activated Sludge

Abstract

We investigated chronic mammalian cell cytotoxicity of wastewaters from four sources and their optical spectroscopic properties with or without chlorination or ozonation. Samples from effluents of activated sludge, nitrification tower, facultative waste stabilization pond, and maturation waste stabilization pond were either chlorinated or ozonated. The wastewater samples were analyzed for fluorescence excitation emission matrix, specific fluorescence index (SFI), and specific UV absorbance at 254 nm (SUVA). Before and after disinfection the wastewater samples were quantitatively analyzed for in vitro mammalian cell cytotoxicity. We found that the organic extracts from the ozonated samples induced lower cytotoxicity responses than those from the chlorinated or the nondisinfected samples. To develop correlations between SFI, SUVA, and cytotoxicity, we analyzed 21 independent samples. Significant linear correlations found among these samples suggest that under the tested conditions, cytotoxicity was preferentially influenced by the fluorescence and SUVA of their composite organic agents. These two spectroscopic parameters may be used as indicators for the potential cytotoxicity of nondisinfected, ozonated, or chlorinated municipal wastewaters.

Global Transcriptional Analysis of Nontransformed Human Intestinal Epithelial Cells (FHs 74 Int) after Exposure to Selected Drinking Water Disinfection By-Products

“…Future research is now needed to investigate the potential augmented risk associated with the presence of DBPs as complex mixtures (Teuschler and Simmons 2003; Massalha et al 2018; Dong et al. 2017; Plewa et al.…”

UV Inactivation of Rotavirus and Tulane Virus Targets Different Components of the Virions

“…Sampling and characterization of wastewater. Water from a reservoir, which is the last step in a series of waste stabilization ponds at a wastewater treatment facility in Illinois, was collected as described previously (39). At this facility, water from this reservoir is regularly disinfected by UV irradiation at 254 nm before being used for irrigation.…”

“…At this facility, water from this reservoir is regularly disinfected by UV irradiation at 254 nm before being used for irrigation. This water was characterized by a total organic carbon (TOC) content of 18.7 mg/liter, 0.65 mg/liter ammonia, a total chemical oxygen demand (COD) of 59 mg/liter, and 18 mg/liter volatile suspended solids (VSS) (39). All disinfection experiments were conducted with this water, and the pH of this water was 8.57, which is typical for the waste stabilization pond (40).…”

Biosolids leachate variability, stabilization surrogates, and optical metric selection

“…4,7 Pilot and bench scale studies have also utilized UV-vis absorbance and fluorescence spectroscopy to assess transformations of sludge or biosolids leachates. 8–13 Optical changes in leachates have been correlated with OM changes due to heat, enzymatic treatments, or composting trials. 8–13 Several studies demonstrate that stabilizing treatments may decrease UV fluorescence emissions at 300–400 nm (classically attributed to soluble microbial products or SMPs), and increases in visible wavelength fluorescence emissions at 400–500 nm (classically referred to as both fulvic and humic acid-like emissions – albeit a debated association).…”

“…8–13 Optical changes in leachates have been correlated with OM changes due to heat, enzymatic treatments, or composting trials. 8–13 Several studies demonstrate that stabilizing treatments may decrease UV fluorescence emissions at 300–400 nm (classically attributed to soluble microbial products or SMPs), and increases in visible wavelength fluorescence emissions at 400–500 nm (classically referred to as both fulvic and humic acid-like emissions – albeit a debated association). 8,10,13,14 Wang et al 8 noted 18-fold increases in SUVA 254 and releases of higher molecular weight leachate signatures after sludge-pumice mixture composting trials.…”