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Parallel to the increase in public concern about the safety of drinking water globally, the demand for bottled water has increased in almost every country. Although tap water is significantly cheaper than bottled water, consumers concerned about the safety of tap water. They still prefer the bottled water despite several checks implemented in tap water networks. The present paper aims to discuss network water quality in the city of Istanbul, Turkey and to present the findings on a related survey conducted by the authors. The survey was conducted with the participation of 980 individuals living in different districts in Istanbul and the findings were assessed to determine the public perception about tap water quality and bottled water consumption especially after the experienced years of drought and water quality concerns. Findings demonstrated that several individuals never drink tap water and certain individuals do not utilize tap water at all. It was found that only 4% in the surveyed group drink tap water without hesitation. Based on survey findings, the abovementioned group was mainly among the lowest income group in the sample. When purchasing bottled water, several individuals preferred the well-known brands. It was found that the most significant reasons for preferring bottled water were the nice taste of the bottled spring water, which was perceived not to exist in tap water. It was concluded that drinking water treatment facilities and regulations are required to cater the future quality demands. Furthermore, it was determined that adequate inspections and controls on network water are necessary.

Indoor dust samples were collected in the summer of 2017 from 10 residential buildings, 7 commercial buildings and 7 official buildings of Bushehr. Sixteen polycyclic aromatic hydrocarbons (PAHs) were analyzed by GC–MS. The sum concentration of the 16 PAHs in dust spanned between 87.8 to 14619 mgkg-1d.w. with a mean of 2211.6 mgkg-1d.w. The mean concentration of PAHs for the dust samples from the commercial buildings was higher than from residential buildings and, from residential building was higher than from official buildings. The cancer risk through dermal and ingestion route ranged from 10-6 to 10-5 across all the dust samples, while the average of cancer risk through inhalation pathway was 10-9 to 10−12, about 104 to 106 times lower, when compared with other two pathways (ingestion and dermal contact). Also, the level of cancer risk for children was significantly higher than the corresponding risk for adults. The results of this work would be suitable to enhance the quality of living environment and human health in Bushehr province.

The slag generated in the rotary furnaces is classified hazardous waste. In this regard, landfill disposal of lead smelting slag is not feasible since a few hundred tons are produced per year; leaching of heavy metals into ground water is of concern. The release of heavy metals into the environment has resulted in a number of environmental problems. The disposal of slag is becoming more expensive each year due to large land areas needed for its disposal. The best way to solve the disposal problem of waste materials is to decrease the quantity for disposal with utilization of waste materials in the industry. The toxicity of the waste is determined by leaching tests and depending on the characteristics of the waste the spent abrasive must be disposed of as solid or hazardous waste. The aim of this study is to investigate leaching characteristics of lead smelting slag according to leaching tests such as TCLP, and TS EN 12457-4 tests methods. In this study, mixed-level factorial design was applied to optimize process parameters for lead removal from lead smelting slag using natural (sepiolite, montmorillonite, illite and seashell) and waste material (red mud). The established model was then used as a predictor to achieve better understanding of the adsorption process and to obtain optimal settings of the experimental factors. The present study includes the safe disposal of lead smelting slag using natural and waste materials. Experimental results indicated that red mud and seashell can be used as environmentally friendly adsorbents that are capable of lead release from lead smelting slag.

The purpose of the study was to improve drinking water quality of conventional treatment processes by combining with UF-membrane systems. Performances of two membrane systems were evaluated in two different full-scale conventional water treatment plants in Istanbul. Low-pressure UF membranes were combined after settling and filtration units of Büyükçekmece and Emirli water treatment plants. Low-pressure UF systems were operated under vacuum and pressure conditions. The experimental results indicated that combining UF systems enhanced drinking water quality with respect to turbidity, TOC and UV254 removal. In all cases, vacuum-driven UF membranes provided higher treatment performance and low energy consumption comparing to pressure-driven system. Combination with UF membranes also reduced disinfection by-products.