International conference on Frontiers in Chemical Technology 2020 (FCT 2020)
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Item Determination of water quality and suitability in a chronic kidney disease of unknown etiology (CKDu) prevalence area, Sri Lanka(Institute of Chemistry Ceylon Adamantane House, Rajagiriya, Sri Lanka., 2020) Botheju, W. S. M.; Liyanage, Janitha A.Chronic Kidney Disease of unknown etiology (CKDu) is a global health obstacle that is presenting as kidney disease in patients who do not show common causative factors, such as diabetes or hypertension. Although the causative factors and major causes for CKDu prevalence are still in debate, most of the external factors which affect the disease are associated with drinking water. Therefore, this study investigated the water quality and suitability of drinking water in a CKDu prevalence area to assess its suitability for human consumption. The water samples were collected from 30 dug wells in Girandurukotte Grama Niladhari Division (GND), Badulla District which reported the highest number of CKDu patients and from Buddhangala GND in Ampara District (as reference sampling site) in dry season. Dissolved Oxygen (DO), Electrical Conductivity (EC) and Fluoride (F) were analyzed as on-site measurements. Calcium (Ca), Magnesium (Mg), Cadmium (Cd), Arsenic (As) were determined using Inductive Coupled Plasma Mass Spectrometry. Sulphate, Nitrate and Chlorides were analyzed using Ion Chromatography. Each analysis was performed in triplicates. The Water Quality Index (WQI) was calculated using standards of drinking water quality recommended by the World Health Organization (WHO). According to the results, pH, DO, EC, F, Ca, Mg, Cd, Cr, Pb, As, total hardness, sulphate, nitrate and chloride values in Girandurukotte GND were 7.03±0.08, 4.8±0.8 mg/L, 396.9±9.1 μS/cm, 1.64±0.04 mg/L, 1.05±0.90 mg/L, 202.85±5.60 mg/L, 0.124±0.074 μg/L, 54.75±0.54 μg/L, 0.20±0.05 μg/L, 30.64±8.60 μg/L, 83.60±4.02, 60.28±5.62 mg/L, 20.56±8.62 mg/L and 122.65±10.36 mg/L respectively. The results obtained for WQI in Girandurukotte and Buddhangala were 71.84 (51-75 poor) and 42.67 (26-50 good) respectively. Results indicate that water samples analyzed from Girandurukotte are not safe for human consumption and other domestic purposes while the water samples in reference site are safe for human consumption. Therefore, taking all necessary precautionary measures before the consumption can be recommended to avoid adverse health impacts.Item Bioaccumulation of nephrotoxic metals in rice grains (Oryza sativa) in a CKDu hotspot in Sri Lanka via soil analysis(Institute of Chemistry Ceylon Adamantane House, Rajagiriya, Sri Lanka., 2020) Dayananda, M. D. N. R.; Liyanage, Janitha A.Accumulation of nephrotoxic metals in edible crops and associated soil is a major international concerns today which results food safety issues and adverse health risks like CKDu. Soils are considered to be an excellent media to monitor and assess chemical pollution where the application, deposition and absorption of chemicals are taken place. Therefore, this study attempts to investigate the bioaccumulation of nephrotoxic metals in soil and rice grains (Oryza sativa) and to interpolate the spatial distribution of selected chemical elements using Inverse Distance Weighted (IDW) and Spatial Autocorrelation tools in ArcMap 10.2.2 software in a CKDu hotspot; Girandurukotte Grama Niladhari Division (GND), Badulla, Sri Lanka via soil analysis. Dambethalawa GND in Ampara district was selected as the reference site. 30 soil samples were collected according to random stratified design including 10 paddy cultivated sites and 10 composite rice grain samples were collected from those paddy fields separately. Microwave digested soil and rice samples were analyzed by inductively coupled plasma mass spectrophotometry. The average concentrations of Cd, Pb, As, Cr, Ca and Mg in soil were 0.45±0.02, 0.20±0.02, 0.65±0.25, 0.29±0.04, 4812.00±692.00, and 15157.00±1275 mg/kg respectively. According to the lower Moran’s indices given by the Spatial Autocorrelation, the selected metals were evenly distributed throughout the sampling area and Cd, Pb, Ca and Mg contents in CKDu prevailed area was significantly higher (p<0.05) than the reference. The higher bioaccumulation factors (from soil to rice grain) (BCF>1) indicated that rice grains tend to accumulate the nephrotoxic metals including Cd;2.35, Pb;7.48, As;2.60 and Cr;5.80. The calculated Enrichment factors (EF) which derives the degree of soil contamination by nephrotoxic metals were Cd;6.49, Pb;6.01, As;1.30 and Cr;1.48 and greater EFs (EF>1) indicates higher availability and distribution of metals in contaminated soil when compared to the reference. It can be concluded that the degree of soil contamination by nephrotoxic metals was higher in the selected CKDu hotspot than the reference. Hence, human renal dysfunctions can be related with consumption of contaminated rice with those metals.Item Effect of fertilizer application to the agricultural soil and the determination of soil to plant transfer coefficients of selected elements(Institute of Chemistry Ceylon Adamantane House, Rajagiriya, Sri Lanka., 2020) Perera, W. P. R. T.; Dayananda, M. D. N. R.; Botheju, W. S. M.; Liyanage, Janitha A.Transfer of metals from soil to plant depends on the availability of particular elements in soil and the fertilizer which are applied to the agricultural fields. This study aims to determine the effect of fertilizer application to the agricultural soil and to determine the soil to plant transfer coefficients of selected elements in Eppawala Grama Niladhari Division (GND), Anuradhapura, Sri Lanka. Fifteen soil and rice root samples were randomly collected from paddy fields and composite fertilizer samples were prepared by adding Urea, Muriate of Potash and Rock Phosphate in the ratios which were used by farmers in sampled area. Metals were analyzed by Inductive Coupled Plasma Mass Spectrometry (ICP-MS-Agilent 7800). Mean concentrations of Cr, Fe, Cu, As, Cd, Pb and Zn in fertilizer composites were 445.00±171.00, 114638.00±46722.00, 92.90±38.40, 178.00±109.00, 5.56±3.41, 912.00±534.00 and 2553.00±1452.00 in mg/kg respectively. Mean concentrations of Cr, Fe, Cu, As, Cd, Pb and Zn in soil samples were 0.22±0.03, 135.10±38.90, 1.37±0.16, 0.25±0.30, 0.01±0.00, 0.32±0.07 and 40±10.3 in mg/kg respectively. The transfer coefficients (TC) of different metals were quantified to indicate the lability of metals in soils. Greater TC value indicates relatively poor retention of metal in soil or greater efficiency of plant roots to absorb metal, and low TC is attributed to strong sorption of metal to the soil colloid. TCs from soil to roots for Cr, Fe, Cu, As, Cd, Pb and Zn were 62.14, 260.04, 46.93, 6.94, 21.26, 14.14 and 3.37 respectively. It indicates that rice roots absorb higher amounts of metals in soil colloids which are resulting mostly from the fertilizer applications. It can be concluded that considerable amount of metals coming from the fertilizers are remaining in the soil and the efficiency of absorbing metals from plant roots is higher than the retention of metals in soil as having greater Transfer Coefficients.Item Study of aqueous calcium ion adsorption competence by coreshell adsorbent granules engineered from sand/graphene oxide nanocomposite(Institute of Chemistry Ceylon Adamantane House, Rajagiriya, Sri Lanka., 2020) Premasinghe, Niroshan; Perera, W. P. R. T.; Fernando, W. S. K.; Liyanage, Janitha A.; Kumarasinghe, A. R.In water treatment, sand unit processes are frequently used to remove turbidity. In order to enhanced the performance of the sand, a surface modification was done using graphite oxide. The core-shell granules were fabricated using graphite oxide coated river sand. Graphite oxide was derived from high purity vein graphite in Sri Lanka. Repeated coating of graphite oxide on the sand followed by low temperature (110 °C) thermal pyrolysis yield hierarchical core-shell structure where several layers of graphite oxide covered the sand particulates. Mineralogical and physicochemical characterization of the novel adsorbent was carried out by Energy Dispersive X-Ray attached to Scanning Electron Microscopy (SEM-EDX), Fourier-Transform Infrared Spectrometry (FTIR), and X-ray Powder Diffraction (XRD). The operational parameters such as contact time, initial calcium ion concentration, adsorbent dose and initial pH of the solution were evaluated in batch procedures at room temperature (26±2 °C) using Five time GO/sand combination which observed as the most effective combination for calcium ion removal from hard water. Characterization studies reveal that uneven coatings of graphene oxide present on the surface of Nanocomposite is containing oxygen-based functional groups (C-O, C=O, O-H) in addition to C-C groups. Optimization studies showed that, the most effective dosage of the adsorbent is 5.0 g with initial calcium ion concentration 50 mg/L. It appears that there was no significant effect on the calcium ion removal over a wide range of pH 4-10 and the process began to reach equilibrium after 20 minutes. Finally, super sand granules show high partiality towards calcium ions and it will be important for the treatment of the hard water and the multiple coated GO/sand combination can be used to regulate excess water calcium and turbidity simultaneously.