Modelling the Effects of Competing Anions on Fluoride Removal by Functionalized Polyacrylonitrile Coated with Iron Oxide Nanoparticles

Fe2O3 nano particles supported on functionalized poly-acrylonitrile was prepared. PAN-oxime-nano Fe2O3 was characterized by XRD, FTIR andTEMand used for fluoride adsorption. The adsorption capacity increased with increasing initial fluoride concentration and reaction time. Fluoride-removal performance of PAN-oxime-nano Fe2O3 was also tested in the presence of various competing anions usually found in drinking water. Competitive sorption between fluoride and competing anions showed a minimum preference for chloride counterions. Carbonate was the greatest competitor for fluoride removal followed by phosphate and sulphate. Counterion presence decreased fluoride adsorption capacity in order of CO32−> PO43−> SO42−> Cl−. The presence of anions at various concentrations decreased fluoride adsorption capacity on PAN-oxime-nano Fe2O3 by 1.22 to 6.51 mg g–1. Effects of each two anions exist simultaneously in aqueous solution on fluoride adsorption was investigated using Tukey’s test (called also a pairwise comparison). Tukey’s HSD results indicate that the differences between various pairs of anions are significant (P < 0.05), except for chloride–sulphate (P = 0.08). In the design of PAN-oxime-nano Fe2O3 for environmental applications, the strong influence of the counter ions must be considered.KEYWORDS Fluoride, PAN-oxime- nano Fe2O3, counterion, adsorption

Occurrence and fate of amoxicillin and penicillin G antibiotics in hospital wastewater treatment plants: A case study � gonbad kavous, Iran

Release of antibiotics to the environment as a result of wastewater effluent discharge is a cause for concern worldwide, as they pose a potential threat to human health and the earth ecosystem. Penicillin and amoxicillin are widely used antibiotics. Despite their rapid hydrolysis in aqueous matrices, their presence in the environment is widely investigated. The current study reported and analysed the current state of four hospital wastewater treatment plants (WWTPs) in Gonbad Kavous, Iran, during 2019, from the perspective of amoxicillin and penicillin G removals. WWTPs were sampled at various stages of the treatment process to determine at which stage the antibiotics are being removed. Concentrations of amoxicillin and penicillin G in raw wastewater, analysed by HPLC, varied from 0.35 to 1.02 and 0.02�0.31 μgL�1, respectively. These values reduced in the final effluent, corresponding to overall efficiency in removing the studied antibiotics of 20-60.5. Anaerobic processes (i.e. septic tank) slightly outperformed aerobic biological processes for both antibiotics� removal, and penicillin G was removed more efficiently than amoxicillin. Effects of wastewater physicochemical properties, including chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total suspended solids (TSS) on antibiotics removal, were also studied. Whereas statistically significant correlations were noticed between COD, amoxicillin and penicillin G removals, their decline showed no correlation with TSS removal. Our study shows that despite the deployment of treatment plants, a considerable amount of antibiotics is released into receiving water bodies, resulting in significant amounts of these pharmaceuticals entering the environment. There is abundant room for further progress in the detection and quantification of pharmaceuticals and other emerging contaminants in hospital wastewaters and their metabolites and biodegradation products. © The Author(s) Published under a Creative Commons Attribution 4.0 International Licence (CC BY 4.0

An innovative drinking water nutritional quality index (DWNQI) for assessing drinking water contribution to intakes of dietary elements: A national and sub-national study in Iran

Drinking water contribution to intakes of dietary elements in urban communities of Iran in 2014 was determined and an innovative drinking water nutritional quality index (DWNQI) was introduced to assess the overall situation. The investigated nutrients were calcium (Ca), chloride (Cl), copper (Cu), fluoride (F), iron (Fe), magnesium (Mg), manganese (Mn), potassium (K), sodium (Na) and zinc (Zn). The DWNQI was developed in five steps as follows: (1) selecting input minerals, (2) assigning weight factor for input minerals, (3) converting the mineral levels to the sub-index values (from 0 to 100), (4) introducing an aggregation function to calculate the DWNQI and (5) Describing the DWNQI scores (from 0 to 100) in five categories as poor (0-44.9), marginal (45.0-59.9), fair (60.0-69.9), good (70.0-79.9) and excellent (80.0-100). The percentages of drinking water in the recommended dietary allowances (RDAs) of Ca, Cl, F, Mg and Na at the nationwide level were 9.9, 7.1, 20.5, 18.5 and 8.8, respectively which were significantly higher than those of the other minerals. At the provincial level, the highest and lowest average scores of the DWNQI (±standard deviation) were observed in North Khorasan and Kermanshah to be 83.7 ± 1.6 and 59.6 ± 5.2 described as excellent and marginal, respectively. The national average score of the DWNQI was 71.5 ± 8.2 (good description). This study indicated that the DWNQI could reliably characterize the drinking water contribution to the mineral intakes without strong sensitivity to any individual element. Based on the observed role of drinking water in intakes of dietary elements, it is recommended that the DWNQI be used in judgment about drinking source water quality. © 2015 Elsevier Ltd. All rights reserved