296 Toxicol. Environ. Health. Sci. Vol. 8(5), 296-301, 2016Water is a vital requirement for all living organisms, including humans. Many water treatment plants are set up to clean contaminated water. The purpose of this study is to evaluate the influent and effluent water quality at various treatment plants and to com-pare the values of water quality variables by plant type. Sampling was conducted at 29 water treat-ment plants in Korea for 1 year. Biochemical oxygen demand (BOD), chemical oxygen demand (COD), and concentrations of suspended solids (SSs), total nitro-gen (TN), and total phosphorus (TP) were analyzed using the standard methods of environment analy-sis. The values of most variables were higher in the influent than in the effluent samples. Compared with other plant types, livestock excretion plants showed higher values of variables in the influent. In correla-tion analysis, BOD and other variables showed a positive correlation. Therefore, this study suggests that improvement measures are required to better the water quality of effluent from water treatment plants.Keywords: Water monitoring, Water quality, WastewaterIntroductionThe human body consists of approximately 57% of water. Water is a vital necessity for all living organisms, including humans. Water requirement has increased with increasing population and industrial development. So, many water treatment plants are set up to clean polluted water 1 . The plants are classified as domestic, industrial, livestock excretion, and human excretion plants depending on their use. Chemical and biological methods of water treatment are applied because waste-water contains organic and metal material. In Korea, there are 937 water treatment plants (domestic: 496, industrial: 162, livestock excretion: 192, and human excretion: 87) 1 . As per the 2014 data, these plants had a total capacity of 26,053,051 ton/day (domestic: 24,982,260 ton/day, industrial: 1,019,819 ton/day, live-stock excretion: 40,029 ton/day, and human excretion: 10,943 ton/day) 1 . International regulations or standards are set to prevent and reduce pollution. According to the National Pollutant Discharge Elimination System (NPDES) by the Environmental Protection Agency (EPA) in USA, the effluent standards of point pollu-tion source are set for each type of treatment plant, and availability of emission is decided for environmental standards 1 . The European Union (EU) obeys the Urban Wastewater Treatment Council Directive (UWWTD) and manages the integrated system of effluent for col-lecting, processing, and emission according to the emis-sion limit value, legislations, and measures 2 . In Japan, variables such as biochemical oxygen demand (BOD) and suspended solids (SSs) and total coliforms (TC) concentration are set as indices of water pollution by Standards of Emission and Law of Drainage System 3 . In Korea, the standard method for regulating and ana-lyzing water quality of effluent includes variables such as BOD; chemical oxygen demand (COD); concentra-tions of SSs, total nitrogen (TN), total phosphorus (TP), and total coliforms; and bio-toxicity 4 . A previous study showed that contaminated water had a negative effect on environment health. It is known that polluted water from industrial plants can induce demasculinization, changes in the function and structure of the reproduc-tive endocrine system, disorders of the immune system, and negative effects on fish egg 5-8 . A study assessing the effects of exposure to polluted water on frog re-ported that effluent leads to changes in the timing of overall development and affects sexual development Lim-Kyu Lee 1, *, Ju-Hyun Kim 2, *, Jaehong Park 3 & Junghwan Kim 41 Korea Southern Power Company Limited, Republic of Korea 2 Department of Physical Therapy, College of Health Welfare, Wonkwang Health Science University, Iksan 54538, Republic of Korea 3 Department of Social Welfare, College of Public Health & Welfare, Yongin University, Yongin 17092, Republic of Korea 4 Department of Physical Therapy, College of Public Health & Welfare, Yongin University, Yongin 17092, Republic of Korea *These authors contributed equally to this work. Correspondence and requests for materials should be addressed to J. Kim (junghwankim3@yongin.ac.kr)Received 11 August 2016 / Received in revised form 30 August 2016Accepted 1 September 2016 DOI 10.1007/s13530-016-0289-6 ©The Korean Society of Environmental Risk Assessment and Health Science and Springer 2016pISSN : 2005-9752 / eISSN : 2233-7784Toxicol. Environ. Health. Sci. Vol. 8(5), 296-301, 2016AbstractWater Quality at Water Treatment Plants Classified by Type
