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Water Quality Improvement: Use of Indigenous Plant Materials
Published in Vinod Kumar Tripathi, Megh R. Goyal, Field Practices for Wastewater Use in Agriculture, 2021
S. Sivaranjani, Amitava Rakshit
Nowadays, it is a serious problem to access the clean water for drinking purpose, because of poor land management systems. The polluted water from sewages, industrial discharge, and runoff from agricultural land severely affects the groundwater source. Therefore, these water resources must undergo treatment process, so that the consumers can get the clean water for drinking and domestic purposes [2]. Treatment of drinking water process is carried out by coagulation, sedimentation, filtration, disinfection process [13]. Coagulants play a major role in the treatment of wastewater (WW). Many coagulants for conventional treatment process include inorganic coagulants (such as: Aluminum sulfate, alum). Organic coagulants act as polyelectrolytes and are obtained from synthetic or plant-based materials [11, 32].
Chemicals in California Drinking Water: Source of Contamination, Risk Assessment, and Drinking Water Standards
Published in Rhoda G.M. Wang, Water Contamination and Health, 2020
Richard H. F. Lam, Joseph P. Brown, Anna M. Fan
California depends on both surface and groundwater for its source of drinking water. Issues relating to the chemical contaminants in drinking water and the potential human health effects in exposure to these chemicals have received increasing public attention, especially in recent years. With its rapid population growth, many utilities may be forced to use lower quality water for drinking water purposes. Chemical contaminants found in drinking water are due to the presence of salts, nitrate, pesticides, herbicides, metals, and organic chemicals that enter drinking water supplies from both natural and human-engineered sources. In addition, water obtained from the Sacramento-San Joaquin Delta contains high concentrations of organic carbon, which can combine with disinfectants used at the water treatment plants to produce THM and other disinfection by-products. These pose a serious problem to utilities using Delta water because they many not be able to comply with the stricter standards for THM and DBP that the U.S. EPA is in the process of developing.
Exposure Characteristics
Published in Stephen S. Olin, Exposure to Contaminants in Drinking Water, 2020
Ted Johnson, P. J. (Bert) Hakkinen, David A. Reckhow
Until very recently, the U.S. EPA has recommended using default drinking water intake rates of 2 liters per day for adults (USEPA, 1980). This value is a total tap water rate, as it includes drinking water consumed in the form of juices and other beverages containing tap water, such as tea and coffee. Numerous studies, however, have generated data on drinking water intake rates that support using a significantly lower default value to represent average adult drinking water consumption, while using 2 liters per day to represent the upper 80th to 90th percentile rate. Consequently, the 1997 Exposure Factors Handbook (USEPA, 1997) recommends 1.4 liters per day as the default drinking water value for adult consumption. The relevant studies and associated data are summarized in Subsection 3.2.4.1.
Evaluation of spatio-temporal variations in water quality and suitability of an ecologically critical urban river employing water quality index and multivariate statistical approaches: A study on Shitalakhya river, Bangladesh
Published in Human and Ecological Risk Assessment: An International Journal, 2020
Md. Humayun Kabir, Tanmoy Roy Tusher, Md. Saddam Hossain, Md. Sirajul Islam, Rifat Shahid Shammi, Tapos Kormoker, Ram Proshad, Maksudul Islam
In this study, higher concentrations of NO2– and NO3– in river water were found to be of particular importance in terms of human and ecological health risks. Although the water of Shitalakhya river is usually not used as drinking water by the local inhabitants, consumption of this river water for drinking or other domestic purposes may pose severe human health hazards. For instance, NO2– and NO3– ingestion via consumption of contaminated drinking water can cause adverse human health outcomes including methemoglobinemia, colorectal cancer, thyroid disease, and neural tube defects (Fan 2011; Ward et al. 2018). On the other hand, NO2– exposure by aquatic animals may result in behavioral and morphological changes, reduced feeding activity, abnormalities and paralysis, hemolymph osmolality, and temperature tolerance (Philips et al. 2002). Moreover, Camargo et al. (2005) reported that freshwater organisms are more sensitive to NO3– as compared to the marine organisms. Higher concentrations of NO3– in river water may cause reduced body size and environmental adaptation of freshwater animals (Camargo et al. 2005). Besides these, temperature disturbance can trigger the effects of NO2– and NO3–, and also influences the metabolic level and biological activity of aquatic organisms as it also influences the tolerance limit (Bhadja and Vaghela 2013).
Spatial risk distribution and determinants of E. coli contamination in household drinking water: a case study of Bangladesh
Published in International Journal of Environmental Health Research, 2020
Jahidur Rahman Khan, K. Shuvo Bakar
Drinking water sources may contain various types of contaminants – microorganisms, (e.g. E. coli, Giardia), inorganic chemicals (e.g. lead, arsenic, nitrates, and nitrites), organic chemicals (e.g. atrazine, glyphosate, trichloroethylene, and tetrachloroethylene), and disinfection by-products (e.g. chloroform) (US Epa 2015). Microbial contaminants include bacteria, viruses, and protozoa that may cause severe water-borne diseases such as diarrhea, gastrointestinal illness (Arnone and Walling 2007; Craun et al. 2006; US Epa 2015). Several studies show that, young aged children are more sensitive to microbial contaminants because of their less developed immune systems compared to the adults (Centers for Disease Control and Prevention 2010; Dietert 2009; Garcia et al. 2000; Nwachuku and Gerba 2004; Thompson 1994; US Epa 2015; Woodruff et al. 2008; Yoder and Beach 2010). The MICS 2012–13 reveals that overall, 61.7% of the population had household water with detectable E. coli contamination (BBS, & UNICEF 2014).
Occurrence of contaminants in drinking water sources and the potential of biochar for water quality improvement: A review
Published in Critical Reviews in Environmental Science and Technology, 2020
Kumuduni Niroshika Palansooriya, Yi Yang, Yiu Fai Tsang, Binoy Sarkar, Deyi Hou, Xinde Cao, Erik Meers, Jörg Rinklebe, Ki-Hyun Kim, Yong Sik Ok
Membrane technology is a candidate method for organic matter removal and functions as a microbiological barrier. In membrane filtration, drinking water is treated through the physical removal of bacteria, virus, and other particles in raw water. Ultrafiltration (UF) membrane is common among the membrane techniques while integrated methods such as combined ozonation with ceramic UF membrane are also being employed (Fan et al., 2014). Poly(ether sulfone) (PES) UF membrane and surface-modified PES UF membrane were used to remove PPCPs and EDCs in water (Rana et al., 2014). It was found that the removal rates were 0 and 6.67% for carbamazepine and bisphenol A for unmodified PES UF, while modified PES UF showed 9.85 and 21.44% removal rates respectively for carbamazepine and bisphenol A. Modified membranes exhibited more specific features and higher efficiency than conventional membranes. However, modification was less effective to increase the charge of the PES membranes, and charge repulsion was not the controlling mechanism for removal in the entire removal process. An excellent removal efficiency of Cu and Pb was seen for bagasse biochar and polysulfone mixed matrix hollow fiber membrane. Maximum adsorption capacities were 24.47 and 79.76 mg/g for Cu and Pb, respectively (He et al., 2017). These findings suggest that the innovative composite membranes with biochar would be an effective technique to adopt in drinking water treatment operations for improving the process efficiency.