Chemistry
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Item Assessing Nephrotoxic Heavy Metal Contamination in Reservoir Sediments: Implications for Human Health and Aquatic Ecosystems(Gampaha Wickramarachchi University of Indigenous Medicine, 2024) Dayananda, M.D.N.R.; Liyanage, J.A.; Kannangara, S.D.Background: Wetlands, often referred to as the "kidneys of the earth," play a crucial role in ecosystem services. This study focuses on reservoirs in dry zone, in Sri Lanka, recognizing their significance in fulfilling diverse ecological needs. Originality/Value: The research addresses the scarcity of studies linking Chronic Kidney Disease of unknown etiology (CKDu) hotspots with heavy metal contamination in reservoir sediments. Objective: The study aims to assess nephrotoxic heavy metal contaminations in reservoir sediments, specifically focusing on the potential health risks for humans through the ecological implications for aquatic ecosystems. Methodology: Ten (10) triplicated composite sediment samples were randomly collected from Ulhitiya, Diwulankadawala, Wahalkada, (within the CKDu hotspots), and Namaloya (the Reference) reservoirs. Inductively Coupled Plasma Mass Spectrometry was employed to determine metal concentrations followed by microwave digestion. Inverse Distance Weighted (IDW) tool in ArcMap. 10.8 Software was used for the spatial interpolations. Findings: Ulhitiya, Diwulankadawala, and Wahalkada reservoirs exhibited elevated contents of Cd, Pb, As, Cr, Cu, and Zn in sediments than the reference. Sediment-bound As, Cu, Zn, and Cd were higher than NOOA-ERL and ERM levels and instead of Pb, all the other selected heavy metals exceeded the LELs, implicating harmful biological impacts on living organisms inhabiting the selected reservoirs in the CKDu hotspots. A clustering pattern in higher concentrations of Cd and Pb was observed near the water inputs of the reservoirs in CKDu endemic areas. Conclusions: Heavy metal contamination in reservoir sediments, particularly Cd and Pb, poses risks to aquatic ecosystems and human health through the food chain, especially in CKDu hotspots.Item Daily intake of essential minerals through drinking water in a chronic kidney disease of unknown etiology prevalence area, Sri Lanka(Proceedings of the Research Conferenc e in Health Sciences 2021, 2021) Botheju, W.S.M.; Liyanage, J.A.; Kannangara, S.D.P.Background: Chronic Kidney Disease of unknown etiology (CKDu) is increasing at an alarming rate in North Central Province, Sri Lanka. Based on previous observations, CKDu has a profound relationship with drinking water quality. The contribution of drinking water to the total dietary intake of essential minerals is pronounced. Essential minerals are required for humans in limited quantities, and excessive or insufficient intake of vital minerals can cause various chronic effects such as CKDu. Objective: This study aimed to assess the essential mineral intake of human body via drinking water obtained from a CKDu endemic area in Sri Lanka. Method: Thirty drinking water samples were randomly collected from dug wells in Girandurukotte grama niladhari division, Badulla District, Sri Lanka. The collected water samples were stored in pre-cleaned containers, sealed, and transported to the laboratory at a refrigerated temperature. They were filtered through 0.45 μm membrane filters. Selected essential minerals, including calcium (Ca), magnesium (Mg), copper (Cu), zinc (Zn), ferrous (Fe), and manganese (Mn), were analyzed using Inductive Coupled Plasma Mass Spectrometry (ICP-Agilent-7800). Mean Oral Daily Intake (ODI) for an adult human was determined in triplicates using the concentrations of essential minerals. Results: The results obtained for Ca, Mg, Cu, Zn, Fe, and Mn were 1.1±0.1 mg/L, 20.3±0.8 mg/L, 1.1±0.0 μg/L, 18.4±1.0 μg/L, 108.3±12.6 μg/L, and 143.0±21.6 μg/L respectively. Mean ODI value (μgkg−1day−1) for Ca, Mg, Cu, Zn, Fe, and Mn were 0.04, 0.74, 3.89x10-5, 0.07x10-2, 0.04x10-1, and 0.01 respectively. Mean concentrations of selected essential elements in drinking water complied with WHO standards except for Mg. Conclusion: The reported chronic ODI values indicate low potential harmful health risks to the people of the study area. However, long-term use of this water may pose a hazard to human health. Therefore, regular monitoring and taking all necessary precautionary measures before using this water can be recommended.Item Quest to Assess Potentially Nephrotoxic Heavy Metal Contaminants in Edible Wild and Commercial Inland Fish Species and Associated Reservoir Sediments; a Study in a CKDu Prevailed Area, Sri Lanka(Expo Health 13, 2021) Dayananda, N.R.; Liyanage, J.A.Inland fish is one of the main protein sources of the regular diets of remote communities in Sri Lanka where the incidences of chronic kidney disease of unknown etiology (CKDu) have significantly increased. Nevertheless, the nephrotoxic heavy metals accumulated in the reservoir sediments may affect the bio-community, especially in fish through the food chains. To study the problem, concentrations of heavy metals (Cd, Pb, As, Cr, Cu, Zn, and Mn) in two common edible wild and commercial inland fish species and associated reservoir sediments were investigated in selected CKDu endemic and non-endemic areas in Sri Lanka. The concentrations of heavy metals were 1000 times higher in sediments than in dorsal fish muscles. Based on SQGs, Sediment-bound As, Cu, Zn, and Cd contents which exceeded the Effect range-low and median levels, implicated the harmful biological impacts to the living organisms inhabiting the Ulhitiya reservoir in the CKDu hotspot, including fish. Significant strong correlations in Cd, Pb, and Zn between the reservoir sediments and dorsal muscles of E. suratensis and O. niloticus confirmed that presume. Calculated Hazard Indices (HIs) were higher in E. suratensis (wild species) than O. niloticus (commercial species) irrespective of the location, and nephrotoxic heavy metals, including Pb, Cd, and As in fish muscles, contributed about 80% to the HI. Whether the estimated Target hazard quotients (THQs) for fish consumption were very much less than the threshold of 1, a relative possibility to the occurrence of chronic kidney failure of CKDu can exist due to exposure to the nephrotoxic heavy metals such as Pb, Cd, and As via fish consumption in the selected CKDu prevalence area. While a pollution event into an inland reservoir is often transitory, the pollutants’ effects may be long-lived due to their tendency to be absorbed in the sediments and then released into the food chain. Even though detected heavy metal contents have complied with acceptable limits for human consumption, long-term consumption as the main animal protein source can directly impact the prevalence of CKDu among the residents in Girandurukotte GND, Badulla, Sri Lanka.Item Chemical speciation modeling of drinking water in chronic kidney disease of unknown etiology (CKDu) affected areas(Department of Forestry and Environment Science, University of Sri Jayewardenepura, Sri Lanka., 2016) Perera, D.H.; Liyanage, J.A.Item Determination of Ash content in Varatika and Abhraka used in Ayurveda Rasa pharmaceuticals(Sri Lanka Association for the Advancement of Science, 2011) Gunaratna, T.A.N.R.; Maduwanthi, J.A.H.; Weerasooriya, W.M.B.; Liyanage, J.A.Varatika is the shell of Cyprea moneta (shell of cowry) and chemically it is identified as a carbonate of calcium (CaCO3). This is used in Rasa Shatra as a key ingredient. Among Abhraka varieties Krishna vajra abhraka (Biotite Mica) is the finest variety used for therapeutic purposes. Mineral compounds that are prepared through Shodhana (purification), Bhavana (trituration) and Marana (incineration) are considered pharmaceutically as the most suitable forms as they are superior, non-toxic and highly potent for therapeutic point of view. Owing to the superiority of mineral drugs in the place of herbal drugs it has been described that the supremacy might be due to their fast action in smaller dose with good palatability. Hence determination of the total ash content and the acid soluble ash content of Varatika and Abhraka bhashma are important, as it could be helpful to understand the effectiveness of those Ayurveda medicines in the human body. Purification of Varatika and Krishna vajra abhraka (six samples each) and preparation of Dhanyabhraka and Dhanyabhraka chakrika were carried out using traditional methods described in authentic Ayurveda texts. Samples were ashed using Muffel furnace and total ash content and acid soluble ash content were determined. Ash content of unpurified and purified Varatika was 55.64% and 57%, respectively. When compared with the traditionally incinerated sample it is lower (8.50%) than the sample incinerated in a Muffle furnace (14%). These results revealed the importance of improving traditional methods using modern techniques for the manufacture of quality Ayurvedic medicines and this result could be useful to interpret the therapeutic effect of Varatika Bhashma used in hyper acidity. The ash content of unpurified Abhraka was 0.94g (±0.00) in 1g of sample and it was 0.95g (±0.01) in 1g of purified sample. Acid soluble ash content has increased during the purification from 5% to 7.8%. Total ash content and acid soluble ash content of Dhanyabhraka was 0.92g (±0.01) and 10% respectively, and 0.66g (±0.01) ash amount was determined in Abhraka chakrika. Acid soluble ash content in Abhraka chakrika was 5.8%. These results highlight the significance of purification process in Ayurveda pharmaceutical preparation.Item Evaluation of ion concentration in selected aurvedic preparations used for iron deficiency anemia(Sri Lanka Association for the Advancement of Science, 2012) Gunaratna, T.A.N.R.; Maduwanthi, J.A.H.; Weerasooriya, W.M.B.; Liyanage, J.A.Item Determination of the concentration of Mercury, Lead and Arsenic in selected ayurvedic medicine(Sri Lanka Association for the Advancement of Science, 2010) Maduwanthi, J.A.H.; Weerasooriya, W.M.B.; Liyanage, J.A.Item Essential metal transfer from nutrient supplement to serum in vitro(Sri Lanka Association for the Advancement of Science, 2010) Ariyaratne, V.U.; Liyanage, J.A.Item Ground water regime in Tsunami affected Southern coastal area of Sri Lanka(Sabaragamuwa University of Sri Lanka, 2006) Piyadasa, R.A.D.; Weerasinghe, K.D.N.; Liyanage, J.A.Item Physiochemical characteristics of ground water in out-skirt of Tsunami affected area; case study in Denipitiya, Southern Sri Lanka(Sabaragamuwa University of Sri Lanka, 2006) Weerasinghe, K.D.N.; Piyadasa, R.U.K.; Wijayawardhana, L.M.J.R.; Liyanage, J.A.