Point of use (POU) household water treatment is increasingly being adopted as a solution for access to safe water. Non-tuberculous Mycobacteria (NTM) are found in water, but there is little research on whether NTM survive POU treatment. Mycobacteria may be removed by multi-barrier treatment systems that combine processes such as coagulation, settling and disinfection. This work evaluated remova...

egionnaires’ disease is caused by Legionella bacteria, which colonize 12–70% of hospital water systems (Lin et al, 1998b). Of the Legionnaires’ disease cases reported to the Centers for Disease Control and Prevention (CDC), 25–45% were hospital-acquired (Benin et al, 2002). Legionella and other opportunistic pathogens colonize water systems; cause pneumonia, wound, and bloodstream infections in...

Inactivation of infectious viruses during drinking water treatment is usually achieved with free chlorine. Many drinking water utilities in the United States now use monochloramine as a secondary disinfectant to minimize disinfectant by-product formation and biofilm growth. The inactivation of human adenoviruses 2, 40, and 41 (HAdV2, HAdV40, and HAdV41), coxsackieviruses B3 and B5 (CVB3 and CVB...

The legal biological survey of swimming pool waters is based on both the level of bacteriological contamination and the amount of material of fecal origin. The great number of soil amoebas and the occasional epidemiological risk involved led us to consider using these organisms as possible biological markers to estimate the quality of pool water and the extent of disinfection. During a 1-year s...

Abstract The sequential use of disinfection strategies for drinking water treatments has been shown to provide levels of inactivation greater than those corresponding to the single-step disinfection effects (Corona-Vasquez et al., 2002; EPA, 1999). Therefore, a disinfectants combined system could be applied both for the inactivation of microorganisms, resistant to traditional treatments, and al...

In this study, a Computational Fluid Dynamics (CFD) model was developed to evaluate ultraviolet disinfection applesauce reactor. To simulate UV reactors, three sets of equations, including hydrodynamics, radiation and species mass conservation were solved simultaneously. The Realizable k-e turbulence model and the discrete ordinate method were used to find the UV radiation profile through the r...

We investigated recreational vehicle (RV) water reservoirs in response to a case of pneumonia in which Legionella pneumophila was cultured both from the patient and a RV reservoir in which he travelled. Water samples processed and cultured at the CDC according to standard protocol were positive for Legionella spp. in 4/17 (24%) faucets, 1/11 (9%) water tanks from 4/20 (20%) RVs from three diffe...

Despite the low nutrient level and constant presence of secondary disinfectants, bacterial re-growth still occurs in drinking water distribution systems. The molecular mechanisms that starved bacteria use to survive low-level chlorine-based disinfectants are not well understood. The objective of this study is to investigate these molecular mechanisms at the protein level that prepare starved ce...

The solar disinfection of water (SODIS) is a simple technique used to destroy pathogenic microorganisms and so it can improve microbiological quality of drinking water. Many countries are in good positions with respect to receiving solar radiation and Iran ranks first in this regard. Thus, it is important for health authorities to prefer this simple method for use in rural areas of the Country ...

Conventional drinking water production includes coagulation-flocculation, settling followed by sand filtration and chlorine disinfection. In order to avoid algae proliferation, pre and intermediate chlorination is usually effected. During these previous oxidation steps, water contains higher loads of organics; thus formation of chlorinated disinfection by products (DBP), such as trihalomethanes...