Dichloroacetate (DCA) is a toxicant by-product from the chlorination disinfection process for municipal water. The levels would not affect people with normal renal and liver function. However, people with impaired renal or liver function may have an increased susceptibility to DCA toxicity as those are the organs affected by DCA. People (and rodents) with polycystic kidney disease (PKD) are pol...

Small drinking water treatment systems (serving <10,000 population) in rural communities frequently encounter multiple challenges in water quality and federal regulatory compliance, especially the disinfection byproduct (DBP) regulations, due to source water variations, limited resources, and aging infrastructures. Unlike most studies on the DBP control using synthetic water in laboratory setti...

Various natural organic matter (NOM) constituents were evaluated in terms of their biodegradability, disinfection byproduct (DBP) formation potentials, and membrane fouling. The biodegradability of NOM was evaluated with respect to biodegradable dissolved organic carbon (BDOC) and its inhibition control. NOM was divided into (i) colloidal and noncolloidal NOM, using a dialysis membrane with a m...

Worldwide transfer and introduction of non-indigenous species in ballast water causes significant environmental and economic impact. One way to address this problem is to remove or inactivate organisms that are found in ballast water. In this study, 3 experiments were conducted in Puget Sound, Washington, USA, using a prototype ozone treatment system installed on a commercial oil tanker, the S/...

Natural organic matter (NOM) can affect the performance of water treatment processes, and serves as a main precursor for the formation of disinfection byproduct (DBPs) during chlorination. To minimize such undesirable effects, a better understanding of its structural information and reactivity toward chlorine is necessary. In this study, electrospray ionization coupled to Fourier transform ion ...

Wastewater treatment plants in Ohio and elsewhere in the U.S. operating with MBR systems are required to disinfect permeate. This requirement results in an increased cost to both capital and O&M, and with chlorination there is a potential increase in the formation of disinfection byproducts. Disinfection following MBR treatment may not be needed if the MBR process alone removes microorganisms a...

BACKGROUND Biofilms are composed of communities of micro-organisms adhering to essentially any surface. We evaluated whether biofilm formation in the hydraulic circuit of a purposely contaminated haemodialysis monitor would modify the efficacy of different disinfection modalities against bacteria and endotoxin concentrations. METHODS A water-borne Pseudomonas aeruginosa (109) suspension was r...

This research investigated a membrane bioreactor (MBR) process for removing biodegradable organic matter (BOM) and trihalomethane (THM) precursors from pre-ozonated water. Bench-scale and mini-pilot-scale MBR experiments were conducted using powdered activated carbon (PAC) and acclimated biomass. Dissolved organic carbon (DOC) was removed through a combination of adsorption and biodegradation m...

Chloramination of drinking waters has been associated with N-nitrosodimethylamine (NDMA) formation as a disinfection byproduct. NDMA is classified as a probable carcinogen and thus its formation during chloramination has recently become the focus of considerable research interest. In this study, the formation mechanisms of NDMA from ranitidine and trimethylamine (TMA), as models of tertiary ami...

A systematic experimental study was conducted using a pilot-scale drinking water distribution system simulator to quantify the effect of hydrodynamics, total organic carbon (TOC), initial disinfectant levels, and pipe materials on chlorine decay and disinfection byproduct (DBP) formation. The first phase of the experiments focused on the variables of flow rate and pipe materials and their effec...