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Item Cadmium and arsenic levels in edible fishes, Oreochromis niloticus (Nile tilapia) and Ompok bimaculatus (Pena walaya) from Padaviya reservoir of North Central Province, Sri Lanka(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Weerasekara, K.A.W.S.; Pathiratne, A.; Kithsiri, H.M.P.Oreochromis niloticus (Nile tilapia) and Ompok bimaculatus (Pena walaya) are two edible fish species captured in the reservoirs in the North Central province. Objective of this study was to assess the cadmium and arsenic levels in muscle, liver and kidney tissues of O. niloticus and O. bimaculatus inhabiting the Padaviya reservoir to assess association of metal/metalloid levels in tissues with body weights, and total lengths of the fishes. The body weight (180-300g; 110-225g) and the total length (19.0-24.1cm; 24.0-34.0cm) of Nile Tilapia (n=30), and Pena walaya (n=30) respectively were recorded during three sampling events in 2018. The tissues were analyzed for cadmium and arsenic levels using Inductively Coupled Plasma Mass Spectrometry. Cadmium and arsenic contents of the muscle tissues were below the limit of detection (LOD) (<0.05 mg/kg wet weight) except cadmium in the muscle tissues of five Nile tilapia (0.05-0.10 mg/kg). Cadmium contents in the liver tissues of both Nile tilapia and Pena walaya, ranged from <0.05 to 0.14 mg/kg (wet weight) where cadmium levels of 67-70% of the fishes were below the LOD. Arsenic levels in liver tissues of Nile tilapia and Pena walaya were <0.05–0.10 mg/kg and <0.05–0.06 mg/kg respectively where arsenic levels in 83% of Nile tilapia and 97% of Pena walaya were below the LOD. Cadmium content in the kidney tissues of Nile tilapia and Pena walaya were <0.05-0.90 mg/kg and <0.05-0.40 mg/kg respectively where cadmium levels in 30% and 33% fishes were below the LOD. Arsenic was detected only in kidney tissues of 10% Nile tilapia (<0.050.46 mg/kg). Cadmium contents in liver tissues of Nile tilapia positively correlated (p <0.05) with the total length. No other significant associations were found between the metal/metalloid content in the tissues and the body size of the fishes. Results revealed that the cadmium and arsenic contents in the edible muscle tissues of most of these fishes were within the safe limits specified by the regulatory authorities for human consumption. Bioaccumulation pattern of cadmium in the tissues of both fishes followed the order: muscle < liver < kidney, showing greater cadmium bioaccumulative capacity in the kidney tissues. Periodic monitoring of metal/metalloid levels in edible fishes in Padaviya reservoir is recommended considering human safety. The data generated in this study can serve as baseline information for future monitoring and human health risk assessment programmes.Item Presence of arsenic in agrochemicals and their association with the agricultural chronic kidney disease in Sri Lanka(The Journal of Toxicology and Health, 2014) Jayasumana, C.; Fonseka, S.; Fernando, A.; Jayalath, K.; Amarasinghe, M.; Paranagama, P.Chronic Kidney Disease of Agricultural origin (CKDa) formerly known as Chronic Kideny Disease of unknown etiology (CKDu) is one of the biggest health problems in Sri Lanka. In recent years, a significant increase in CKDa cases have been observed in North Central Province (NCP) in Sri Lanka. Since majority of CKDa patients are farmers with chronic arsenic toxicity, the present study was aimed to assess the source of the arsenic in CKDa patients in selected rice farming areas, Padaviya, Mahawilachchiya and Polpithigama and evaluate the amounts of arsenic present in agrochemicals used by these farmers. This study was concentrated on the analysis of agrochemicals; synthetic and natural fertilizers and pesticides which continuously affect the human health. Samples of synthetic fertilizer, organic fertilizer and pesticides (insecticides, weedicides and fungicides) collected from selected CKDa prevalence areas were analyzed using atomic absorption spectrometer using hydride generator and graphite furnace. The highest amount of arsenic contamination was reported from triple super phosphate (TSP) used in cultivation of rice and it was in the range from 25 mg/kg to 37 mg/kg. Since the consumption of TSP for cultivation in Sri Lanka in 2012 was approximately 108,000 MT, the amount of arsenic introduced to Sri Lankan agricultural soils through imported TSP was calculated to be about 2100 kg. On contrary, organic fertilizer prepared with plant organic matter contained very low amounts of arsenic. Investigations carried out to detect presence of arsenic in pesticides showed 0.18 ppm to 2.53 ppm concentration of As. Arsenic has already been identified as one of the major etiological factors for the rapidly spreading CKDa among paddy farmers in the dry zone of Sri Lanka. Since analysis of soil profiles in the endemic areas had previously confirmed that source of arsenic is not from the bed rock, findings of the present study suggest that agrochemicals are the major source of arsenic in CKDa endemic areas.