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Item Assessment of groundwater contamination with environmental toxicants in CKDu endemic area, Polonnaruwa, Sri Lanka(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Perera, W. P. R. T.; Dayananda, M. D. N. R; Botheju, W. S. M.; Liyanage, J. A.Chronic Kidney Disease unknown etiology (CKDu) is one of the major health impacts predominantly confined to people in North Central Province in Sri Lanka. The root courses for the disease prevalence have not found yet. Therefore, this investigation was carried out to determine the groundwater contamination with environmental toxicants: Cadmium (Cd), Chromium (Cr), Copper (Cu), Lead (Pb), Zinc (Zn), Arsenic (As), Iron (Fe), Calcium (Ca), Magnesium (Mg) Fluoride (F), Sodium (Na) and Aluminium (Al) in Dimbulagala Grama Niladhari Division (GND) in Polonnaruwa District, Sri Lanka. The study investigated the groundwater quality of Dimbulagala GND in dry zone of Sri Lanka to assess its suitability for drinking purposes. Only Ten working tube wells were found in the studied area and groundwater samples were collected from the tube wells. Basic physicochemical parameters (pH, temperature, conductivity and dissolved oxygen), (Hatch HQ14d) and fluoride content were determined (Orion Star- 2014) onsite. Environmental toxicant concentrations were determined using Inductive Coupled Plasma Mass Spectrometry (ICP–MS, Agilent 7800). Results were analyzed using SPSS statistical software. descriptive statistics were performed on the data set and the Pearson correlation was applied. According to the results obtained from the onsite investigations the mean values of pH, conductivity and fluoride content were 7.78 (+1.28), 520 us/cm (+148) and 1.20 mg/l (+0.32) respectively. The mean value of the fluoride content has exceeded the permissible limit (1.0 mg/L), (SLS 614-2013). It was highlighted that significant toxic heavy metals such as Lead (Pb), Cadmium (Cd), Chromium (Cr) and Arsenic (As) levels as well as other metals like Fe, Cu, Zn, Na, Al have not been exceeded than permissible limits (SLS 614-2013). Statistically evaluation process proved none of the positive correlation is reported between heavy metal concentrations and Fluoride content of the groundwater in the studied area. But a negative correlation was reported between Fluoride and Cr (p= -0.05) in the groundwater in the studied area. Ca and Mg concentrations ranged between 3.43 mg/l to 130.56 mg/L And 6.54 mg/L to 75.32 mg/L respectively. Although mean Ca (10.12 mg/L) and Mg (15.45mg/L) did not exceed the permissible levels (100 mg/L and 30 mg/L for Ca and Mg), 40% and 50% of individual samples for Ca and Mg levels exceeded the permissible levels respectively. There is an urgent need for establishing proper long term drinking water treatment method for the studied area because of long term exposure to heavy metals such as Cd, Pb, Cr, As, and high levels of Fluoride as well as other environmental toxicants can be harmful to people. These findings can be used as a benchmark of raw water quality in the design processes of treatment plantsItem In depth analysis of groundwater quality and use of Moringa oleifera leaf powder treatment to improve physico-chemical properties and drinkability of contaminated groundwater(Environmental Nanotechnology, Monitoring & Management, 2019) Wijeyaratne, W. M. D. N.; Suvendran, S.Groundwater is the major source for domestic, and other uses in the Jaffna Peninsula, Sri Lanka. This study assessed the spatial and seasonal variation of physical and chemical parameters of water collected from domestic wells in Chunnakam and Vadamaradchi aquifers. The measured physicochemical parameters were compared with the drinking water standards established by Sri Lanka Standards Institution. Significant spatial variations in the water quality parameters were identified in both areas. Significantly elevated levels of nitrate and oil & grease were identified in Chunnakam, whereas significantly elevated levels of DO and pH were recorded in Vadamaradchi. Nitrate concentration of the wells ranged between 0.021–40.1 mg/ L. Oil & grease of these wells ranged from 0.011 to 0.373 mg/L. In Chunnakam, 60% of sampled wells had nitrate level above the permitted nitrate standard level, and all the wells had elevated oil and grease concentration above the permitted standard limit. Filtration of water through Moringa oleifera leaf powder could significantly reduce the nitrate an oil and grease concentrations, thereby improving the quality of water.Item Assessment of drinking water quality of domestic wells in Chunnakam and Vadamaradchi, Jaffna peninsula(Sri Lanka Association for the Advancement of Science Proceedings of the 73rd Annual Sessions, 2017) Suvendran, S.; Wijeyaratne, W.M.D.N.An assessment of the quality of drinking water was carried out by measuring 12 selected physicochemical parameters for selected domestic wells in Chunnakam and Vadamaradchi areas of Jaffna. Vadamaradchi is used as the reference site, as this area is considered to have the best fresh water in Jaffna peninsula. The measured physico-chemical parameters of water from selected domestic wells were compared with the standards established by World Health Organisation (WHO) and Sri Lanka Standards Institution (SLSI) for drinking water. Spatial and temporal variation of parameters among sites was analysed using Two-way ANOVA. The characteristic water quality parameters of the sampling sites were identified using Principal Component Analysis (PCA). Significantly high concentrations of nitrate and oil & grease were recorded in Chunnakam (p<0.05), whereas significantly high dissolved oxygen (DO) and pH were recorded in Vadamaradchi. Nitrate concentration of the wells ranged between 0.021 – 40.1 mg/L, while 30% of these wells exceeded WHO permitted nitrate standard level, 11mg/L. Oil & grease (OG) of the wells ranged from 0.011 to 0.373mg/L, while 70% of wells in Chunnakam exceeded the SLSI permitted standard limit for OG, 0.2mg/L. A significant temporal variation of DO, total solids and total hardness was recorded in Chunnakam, while pH, DO and total phosphorus showed significant (p<0.05) temporal variations in Vadamaradchi. The wells in Vadamaradchi were characterized by high DO, low nitrate, and low OG, while the wells in Chunnakam were characterized by high nitrate and OG. The values recorded in the current study can serve as baseline values for future water quality monitoring and management studies in Chunnakam and Vadamaradchi.Item Optimization of monoplex and multiplex PCR assays to detect meat species and adulteration of meat products in the Sri Lankan market(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Kothalawala, S. D.; Karaliyadda, S.; Fernando, A. L.; Karaliyadda, M.; De Silva, V.Meat identification testing, detecting intentional adulteration of meat and detecting meat contamination due to poor processing practices are essential to ensure good quality of meat products. Incidence of meat adulteration, product mislabelling, commercially motivated adulteration and contamination of meat products with undesired or forbidden meat species have been reported in some countries. In Sri Lanka, religious and cultural views are one of the primary determinants of choice of meat consumed. Therefore, the necessity for a rapid, sensitive reliable and reasonably cost effective assay that can determine the quality of meat products is high. Even though this need exists, no such reachable methods are currently available to the Sri Lankan meat producers to determine and certify the quality of their products. PCR based DNA methods are the gold standard in food species identification due to its less time consumption, specificity and sensitivity. The present study optimized monoplex and multiplex PCR assays to detect the meat species and to detect any adulterants or contaminants present in meat products. DNA was isolated by high salt TNES extraction method, from samples of raw meat and processed meat obtained from retail outlets in Colombo. The isolated DNA was amplified using PCR which demonstrated the specificity of the adopted primers to each species of raw meat. Mixtures of meat DNA were then subjected to optimized multiplex PCR; chicken-pork and beef-pork assays to detect each of the types of meat present in the mixture. Processed products of chicken (5) and beef samples (5) were subjected to these optimized multiplexes. The assay was found to be effective in determining the species of meat present in meat products containing chicken, beef and pork, clearly demonstrating species specific bands of 266 bp, 271 bp and 149 bp respectively. These PCR assays are useful in detecting main products and the contamination at the same time with reliable accuracy and specificity which can fulfil the requirement of quality testing of meat products that is important for the consumer, the meat industry and organizations that have an interest in food safety and quality. It is also economical and has wider applicability since many species can be detected with one assay. Compared to other available methods which sometimes fail to be effective when used on highly processed samples, PCR can be applied efficiently. Therefore, it is presented as a suitable assay for identification of meat species and for the detection of adulterants and contaminants in processed meat samples.