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Gloves
Published in Robert N. Phalen, Howard I. Maibach, Protective Gloves for Occupational Use, 2023
Marie-Noëlle Crépy, Pierre Hoerner
For gloves that are not polymer-coated, in-line chlorination is generally performed after vulcanization of the glove. The product is immersed in a dilute aqueous chlorine solution for a short time (a few seconds). The chlorine rapidly reacts with the rubber surface of the product, which results in a lower coefficient of friction. The chlorination also results in a reduced level of extractable latex proteins, both due to the extra leaching achieved by the water and also due to the formation of insoluble forms of some proteins.22 After chlorination, it is necessary to wash the products to remove excess chlorine, and this is done by using dilute aqueous ammonia solution and then rinsing in water.
Fungi and Water
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
The last step is disinfection. Disinfectants used in tap water treatment are chlorine or chloramine. Chlorination is added in order to kill any remaining parasites, bacteria, and viruses, and to protect the water from germs when it is piped to homes and businesses (175–176). However, chlorination is less effective at removing protozoa, such as Giardia lamblia. Chlorine-resistant protozoa and viruses are instead removed by extensive filtration methods (169).
Communicable diseases
Published in Jan de Boer, Marcel Dubouloz, Handbook of Disaster Medicine, 2020
Infectious agents can rarely be attacked directly in the environment; usually, intervention must take the form of controlling transmission and this may be: – physical, e.g. mosquito nets to prevent contact between mosquitoes and humans.– hygienic e.g. personal hygiene to reduce contact between faecal matter and humans.– chemical, e.g. water chlorination, insecticides.
Pollution assessment and estimation of the percentages of toxic elements to be removed to make polluted drinking water safe: a case from Nigeria
Published in Toxin Reviews, 2023
Johnbosco C. Egbueri, Daniel A. Ayejoto, Johnson C. Agbasi
The acidity, basicity or neutrality of water is determined by its pH. It is responsible for water’s biological habitat. A significant change in the pH level of a body of water can be lethal to aquatic life. Table 1 shows that pH values in this study area ranged from 4.0 to 6.4, with an average value of 4.98, showing that groundwater is acidic in nature and falls below the allowable limit of 6.5 set by the NIS (2007) and WHO (2017). This is due to geogenic and anthropogenic influences, rendering the groundwater in this area unfit for human consumption. The pH values increased when the concentrations of CO2, carbonate, and bicarbonate in the water varied. Tuberculosis can be caused by pH levels that are too low. Higher values may cause incrustation, silting, deposition, and certain difficulty in water disinfection with chlorination (Vandal et al.2009). For example, when the human body is acidic, the solubility and adsorption of PTHMs increases, resulting in enhanced bioaccumulation and bioavailability of the PTHMs (The Tyent Team 2019).
Reducing free residual chlorine using four simple physical methods in drinking water: effect of different parameters, monitoring microbial regrowth of culturable heterotrophic bacteria, and kinetic and thermodynamic studies
Published in Toxin Reviews, 2021
Razieh Sheikhi, Amir Hossein Mahvi, Abbas Norouzian Baghani, Mahdi Hadi, Armin Sorooshian, Mahdieh Delikhoon, Somayeh Golbaz, Arash Dalvand, Fatemeh Johar, Mohammad Rezvani Ghalhari
Chlorination is used to destroy the pathogens, remove taste and odor, oxidize some metals, and prevent algal growth and regrowth of microorganisms in drinking water distribution networks (National Research Council (US) Safe Drinking Water Committee 1980, Gopal et al. 2007). During the transportation of treated water via these networks, it may be polluted again (Pourshafie et al. 2007, Bakhshi et al. 2009). Hence, by keeping some of the disinfectant residues in the treated water, it could be protected against probable secondary contamination (Randtke 2010, Rostamia et al. 2017). Free residual chlorine (FRC) can be used as the disinfectant residues in the drinking water distribution networks, which includes hypochlorous acid (HClO), hypochlorite (OCl−), and chlorine gas (Randtke 2010).
The influence of chlorination timing and concentration on microbial communities in labyrinth channels: implications for biofilm removal
Published in Biofouling, 2019
Peng Song, Bo Zhou, Gary Feng, John P. Brooks, Hongxu Zhou, Zhirui Zhao, Yaoze Liu, Yunkai Li
Labyrinth channels are widely used in cooling channels of precision molds, pressure relief structures for pressure-reducing valves, water channels for water pump seals, and flow channel structures for drip irrigation emitters in agriculture. The growth of biofilms in the flow channels leads to the clogging of the entire flow channels and reduces their effectiveness, especially in the field of drip irrigation emitters. Since the first international drip irrigation conference held in Israel in 1971, many scientists have tried to solve the clogging problems in drip emitters with labyrinth channels by installing filter equipment properly, treating with acid and chlorine periodically, and optimizing the design of emitter channels (Li et al. 2008; Duran-Ros et al. 2009; Katz et al. 2014; Oliver et al. 2014). The control of attached biofilms in the labyrinth channels has become the key to solving emitter bio-clogging, which is a problem for microirrigation. As the reuse of reclaimed water for farmland irrigation has become much more common, it has received international support (Castro et al. 2015). Drip irrigation is one of the best and fastest-growing agricultural water-saving irrigation technologies, and its use has grown at an average annual rate of 33% around the world over the last 20 years (Zhang 2015), making the development of biofilm control strategies for labyrinth channels even more relevant. Chlorination is a widely used biofilm control method, but its effectiveness is not clear for complex microbiological control mechanisms and processes.