Water is the basic essential for living. It plays an important role in the environment and human life. Fluoride (F) and arsenic (As) are impotent elements that cause health problems in people living around the world. F and As contamination in the groundwater due to anthropogenic activities and natural sources. These activities are weathering and erosion of rocks, brick kilns, biological activities, wood preservatives usage, paints, metals, soaps, fertilizers, different herbicides, pesticides, dyes, and drugs ( Farooqi et al. 2009; Rasool et al. 2016). But brick kilns are the main source of fluoride and arsenic in groundwater. Low-quality fuel is used in brick kilns for instance; oily sludge, coal, rubber tires, wasted oil, wood, etc. (Khalid and Mansab 2015). F concentration of more than 1.5mg/L in drinking water can cause skeletal fluorosis, kidney stones, decrease birth rates, tooth decay, and bone weakness in humans ( Guo et al. 2007; Khalid and Mansab 2015). While As concentration of more than10 µg/L in drinking water can cause hepatitis, skin, and lung cancer respectively (Khalid 2019).
Arsenic contamination in groundwater is extending from east to west (Japan to the United States), Latin America (Argentina, Mexico, Chile), Europe (Poland, Hungry), and Asia (China, Japan, India, Bangladesh, Pakistan, Taiwan) (Bhowmik et al. 2015; Shakoor et al. 2015). According to several types of research, As pollution in drinking water is significant, exceeding WHO guidelines, putting 200 million people globally and approximately a hundred million people in Asia at danger of As poison (Bhowmik et al. 2015; Rasool et al. 2015; Shahid et al. 2015; Shakoor et al. 2016). Pakistan, China, Japan, India, Sri Lanka, Germany, Ghana, Senegal, Kenya, Turkey, Algeria, Ethiopia, Uganda, Tanzania, South Africa, New Zealand, Mexico, Thailand, and also Argentina are among the F impacted countries (Rasool et al. 2016; Rafiq et al. 2017). In dry and semi-arid parts of the world, arsenic and F in groundwater are widespread (Farooqi et al. 2007; Rasool et al. 2016).
Lately, the contamination level of As and F is high in the groundwater of Pakistan (PSQCA, 2017), thereby people who are living in the Indus valley (about 50–60 million) can be affected (Podgorski et al. 2017). Around 95% of the population in Pakistan depend on groundwater, moreover, they lack awareness and precautionary measure to combat with this problem (Rafiq et al. 2017). Since 1999, UNICEF and PCRWR have recognized for estimation of the quality of drinking water. These agencies have thoroughly sampled groundwater and detected As in the range between (10–200 µg/L) and F in the range (> 1.5 mg/L), especially in various areas of Punjab, Pakistan (Toor and Tahir 2009). In addition to them, the urban areas of Lahore, Sheikhupura, Multan, Bahawalpur, and Hyderabad are significantly contaminated by arsenic and Fluoride (WHO 2008; PSQCA 2017). Approximately 61–73 percent of inhabitants in the Sindh province of Pakistan are struggling from chronic toxicity of As and F (Kazi et al. 2009). In another study from District Vehari showed in which 95percent of groundwater was not suitable for drinking indicating huge amount of As and F in the aquifer of this district that might have adverse impact on human health upon consumption of such water (Shahid et al. 2017).
The District Vehari is a component of Southern Punjab and is situated in the active flood plains of the Indus River in Pakistan. It is a neglected and poor area of Pakistan. In Pakistan, there is limited research focusing on the environmental concern of As and F in drinking water. The objectives of my research are 1) to determine the spatial distribution, characteristics of fluoride or arsenic concentration in drinking water, 2) to elucidate the source identification of fluoride and arsenic contamination using multivariate analysis and possible mechanisms producing high fluoride in the drinking water, and 3) to calculate health risk assessment of fluoride and arsenic intake water for drinking purposes.