Rajith Perera

@inproceedings{Gunathilka2023,

title = {Toxic metal contamination in food chains via paddy plant; A study in CKDu endemic area in North Western Province, Sri Lanka},

author = {VHNM Gunathilka and WPRT Perera and PLRA Perera and CC Kadigamuwa and JA Liyanage and WAPJ Premaratne},

url = {https://www.researchgate.net/publication/377600053_Toxic_metal_contamination_in_food_chains_via_paddy_plant_A_study_in_CKDu_endemic_area_in_North_Western_Province_Sri_Lanka



https://conf.kln.ac.lk/iprc/media/attachments/2024/01/23/abstract-volume-2023.pdf},

year  = {2023},

date = {2023-11-24},

volume = {23},

number = {22},

issue = {2023},

pages = {31},

publisher = {International Postgraduate Research Conference (IPRC)},

address = {Department of Chemistry, Faculty of Science, University of Kelaniya, Sri Lanka},

organization = {University of Kelaniya, Sri Lanka},

abstract = {This study addresses the urgent need for a comprehensive risk assessment of toxic metal contamination in the food chain via paddy plants in CKDu-affected areas emphasizing the health hazards associated with the transfer of toxic metals from soil to paddy grains and evaluating the health risk of consuming rice through different risk indices. Twenty composite paddy soil samples and twenty paddy plant samples with rice grains in the exact locations were collected from paddy areas in Nikawewa Grama Niladhari division during the Maha growing cycle in 2023. The analysis of Cr, Pb, As, Cd, Ni, and Cu was conducted using inductively coupled plasma-mass spectrometry (ICP-MS). Descriptive statistics revealed the average metal concentrations in rice grains as: Cr(637.42±157.44 µg/Kg), Pb(262 ±62.35 µg/Kg), As(39.29±11.97 µg/Kg), Cd(1836±192 µg/Kg), and Cu(1567 ±466 µg/Kg). Cr, As, and Cu levels in rice grains remained within WHO/FAO and codex limits. However, average Pb and Cd levels surpassed permissible limits (Pb-200 µg/Kg, Cd-50 µg/Kg; WHO). Nevertheless, the Target hazard quotient(THQ) values of Cr and Cd were greater than 1. The estimated Daily Intake(EDI) values of Cr(3.15 µg/Kg/Day) and Cd(9.15 µg/Kg/Day) are higher than Tolerable Daily Intake(TDI) values. The transfer factors(TF) for toxic metals in the soil-root system were determined as follows: Cr-0.069, Pb-0.30, As-0.67, Cd-0.49, Ni-0.10, Cu-0.23. Toxic metal transfer factors in the soil-root system were evaluated, indicating greater uptake by plant roots. When considering a metal transfer from roots to rice grains, Cd had a transfer factor greater than 1, indicating potential accumulation in grains, while Cr exhibited a notable increase in transfer factor compared to the soil-root system. The risk of toxic metal transfer from soil to paddy grains warrants concern due to potential human exposure and related health risks, including Chronic Kidney Disease, from the consumption of contaminated rice grains.},

keywords = {Contamination, Food Chain, Heavy metals, paddy soil, Risk assessment},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{Perera2023d,

title = {Advancements in multifunctional core-shell adsorbent comprising graphene oxide/ sand for adsorptive removal of water contaminants},

author = {WPRT Perera and PLRA Perera and JA Liyanage and AR Kumarasinghe},

url = {https://www.researchgate.net/publication/377600187_Advancements_in_multifunctional_core-shell_adsorbent_comprising_graphene_oxide_sand_for_adsorptive_removal_of_water_contaminants



https://conf.kln.ac.lk/iprc/media/attachments/2024/01/23/abstract-volume-2023.pdf},

year  = {2023},

date = {2023-11-24},

urldate = {2023-11-24},

volume = {23},

number = {25},

issue = {2023},

pages = {34},

publisher = {International Postgraduate Research Conference (IPRC)},

address = {Department of Chemistry, Faculty of Science, University of Kelaniya, Sri Lanka},

organization = {University of Kelaniya, Sri Lanka},

abstract = {Our study introduces a novel approach to enhance the efficiency of water treatment by developing a porous material (M-GO/S) that combines graphite oxide (GO) with river sand overcoming the limitations of conventional granular media filtration. Synthesized M-GO/S was finally characterized by X-ray Photoelectron Spectroscopy (XPS) after primary characterization via X-ray diffraction (XRD), FT-IR, Ramen, and Scanning Electron Microscopic images (SEM). The adsorptive removal efficiency of M-GO/S on selected toxic metals (Pb, Cr, Cd, and Ni), calcium, and methylene blue dye was investigated under the optimum conditions. The findings reveal the presence of a non-uniform graphene oxide coating on the surface of the sand. The incorporation of oxygenated functional moieties within the structure observed according to the comprehensive analysis of the Carbon 1s (C 1s) spectra of the M-GO/S sample in XPS spectrums and revealed the existence of four distinct carbon species exhibiting binding energies at 284.8 eV, 287.05 eV, and 288.85 eV. These carbon species were identified as C-C/C-H, CO , and COO (epoxy) functional groups, respectively. The adsorption capacities of Pb, Cr, Cd, and Ni were recorded as; 52.2 mg/g, 21.9 mg/g, 38.1 mg/g, and 21.9 mg/g respectively. Under the optimum conditions, the sand/GO nanocomposite demonstrated remarkable efficacy in removing 75% of calcium ions (elevated removal percentage than commercial coal powdered activated carbon) from simulated hard water. Apart from that, under the optimum conditions, M/GO-S was able to mitigate 95% of methylene blue which was identified as a toxic dye from the water. Therefore, based on its versatile characteristics as a multifunctional porous material, the synthesized graphene oxide-sand nanocomposite (M-GO/S) demonstrates significant potential as a viable solution for the treatment of contaminated water.},

keywords = {Adsorption, CKDu, Contamination, Estimated Daily Intake (EDI), Grains, Graphene oxide, Heavy metals, Methylene blue, Water hardness},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{Perera2023e,

title = {Exploring the toxic metal contamination and unveiling the risks in staple grains grown in a CKDu hotspot in Sri Lanka},

author = {MASN Perera and WPRT Perera and PLRA Perera and CC Kadigamuwa and JA Liyanage and WAPJ Premaratne},

url = {https://www.researchgate.net/publication/377600084_Exploring_the_toxic_metal_contamination_and_unveiling_the_risks_in_staple_grains_grown_in_a_CKDu_hotspot_in_Sri_Lanka},

year  = {2023},

date = {2023-11-24},

volume = {23},

number = {24},

issue = {2023},

pages = {33},

publisher = {International Postgraduate Research Conference (IPRC)},

address = {Department of Chemistry, Faculty of Science, University of Kelaniya, Sri Lanka},

organization = {University of Kelaniya, Sri Lanka},

abstract = {Toxic metals in dietary grains could pose health risks from direct ingestion. Thisinvestigation aims to analyze the concentrations of toxic metals in selected dietary grainsand conduct a comparative risk assessment in a region endemic to Chronic KidneyDisease of Unknown etiology(CKDu) in a non-endemic region. Six household fields in theCKDu endemic region in Nikawewa Grama Niladhari Division(GND) and three in thereference region; Wewagedara GND were selected for sampling. Inductively CoupledPlasma-Mass Spectrometry(ICP-MS) was used to determine Arsenic (As), Cadmium (Cd),Lead (Pb), Chromium (Cr), Copper (Cu), and Zinc (Zn) in composite samples collectedfrom both GND areas (pulses; [(Vigna radiata; n=20), (Vigna unguiculata; n=20), (Vignaunguiculata subsp.; n=20)] cereal; [(Oryza sativa; n=30)]. Descriptive statistics revealedaverage As concentrations in samples as follows; Oryza sativa (38.60±13.84 g/kg,) Vignaunguiculata (3.25±1.96 g/kg), As was undetectable in samples of Vigna radiate, andVigna unguiculata subsp. in CKDu endemic area. The average As concentrations of Oryzasativa in the reference area was 5.56±1.87g/kg and As was not detected in other grainspecies. All values complied with FAO/WHO & Codex permissible limits (As-100-200g/kg). The estimated Daily Intake (EDI) value of As (0.257 g/kg/day) in Oryza sativain the endemic area did not exceed the Tolerable Daily Intake (TDI) (As-0.3 g/kg/day).The average concentrations of Cd and Pb were reported in the CKDu endemic area; Oryzasativa (Cd-1276.92±234.42 g/kg, Pb-419.31±98.78 g/kg), Vigna radiata(Cd-571.31±60.71 g/kg, Pb-344.15±93.75 g/kg), Vigna unguiculata (Cd-1354.33±265.34g/kg, Pb-408.56±22.20 g/kg), and Vigna unguiculata subsp.(Cd-1546.23±355.23g/kg, Pb-408.63±115.14 g/kg) and exceeded FAO/WHO permissible limit(Cd-400g/kg, Pb-300 g/kg). But those values were within the limits in the reference areas.However, Cu, Cr, and Zn remained within FAO/WHO safe limits in both regions. A healthrisk can be generated owing to long-term consumption of staple grains grown inNikawewa GND; CKDu endemic area. 



},

keywords = {CKDu, Contamination, Estimated Daily Intake (EDI), Grains, Heavy metals},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{kumari2022investigation,

title = {Investigation of toxic metals contamination status in red raw rice (Bg 350) grown in North Central province in Sri Lanka},

author = {MKJK Kumari and WAPJ Premaratne and PLRA Perera and WPRT Perera and JA Liyanage},

url = {https://www.researchgate.net/publication/367091781_Investigation_of_toxic_metals_contamination_status_in_red_raw_rice_Bg_350_grown_in_North_Central_Province_in_Sri_Lanka},

year  = {2022},

date = {2022-12-01},

urldate = {2022-01-01},

booktitle = { International Postgraduate Research Conference (IPRC)},

pages = {87},

publisher = {Faculty of Graduate Studies, University of Kelaniya Sri Lanka},

abstract = {Red raw rice consumption is high due to its nutritional properties. The chemical components of food

are correlated with their ability to sustain better human health. Rice is the staple food of Sri Lanka.

Although it is a good source of nutrients in a diet, its consumption can also lead to exposure to toxic

metals due to environmental pollution. Rice is grown extensively in the North Central Province (NCP)

where the prevalence of chronic kidney disease of unknown origin (CKDu) is high. This study was

aimed to determine the toxic metal content such as Arsenic (As), Cadmium (Cd), and Lead (Pb) in

domestically grown red raw rice in NCP and assess the risk of these values to human health. A total of

35 samples Of red raw rice were obtained from farmers in NCP during Yala growing cycle in 2021 based

on the eight sampling sites. As, Cd and Pb levels were analyzed by Inductively Coupled Plasma-Mass

Spectrometry (l •Ille potential health risk was estimated by Estimated Daily Intake (EDI). The mean Pb levels

in red raw rice were higher than the FAO/WHO allowable limits (Pb-200 gg/kg) in all the selected areas

except the Rambewa area. The highest mean pb concentration was recorded in the Horowpathana area

as 429.93±100.93 pg/kg. As and Cd values were within FAO/WHO allowable limits (As-200 pg/kg, Cd-

400 gg/kg). The highest mean value of as was recorded in the Medirigiriya area, and it was 97.72±18.19

gg/kg. The highest Cd level was recorded in the Horowpathana area as 60.70±24.39 gg/kg The

estimated daily intake (EDI) values are also significantly lower than the Tolerable Daily Intake (TDI)

(Pb-250 gg/day, Cd-62 gg/day. As-3 gg/day). Dietary exposure is the most common route through

which these toxic metals enter the human body. Long term consumption of red raw rice causes to

accumulate the toxic metals in body tissues and generates adverse health effects of residents in selected

CKDu prevalent areas in NCP. It is suggested that further studies are needed to get a more

comprehensive idea on the public health concerns of toxic metals due to red raw rice consumption in

Sri Lanka.},

keywords = {CKDu, Contamination, Toxic Metals},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{P2023,

title = {Toxic metal contamination of Inland Fish (Etroplus suratensis) in Mahakanadarawa reservoir: A study in a CKDu prevalent area, Sri Lanka},

author = {Lahiru P and WPRT Perera and PLRA Perera and JA Liyanage and WAPJ Premaratne},

url = {https://www.researchgate.net/publication/365029106_TOXIC_METAL_CONTAMINATION_OF_INLAND_FISH_Etroplus_suratensis_IN_MAHAKANADARAWA_RESERVOIR_A_STUDY_IN_A_CKDu_PREVALENT_AREA_SRI_LANKA},

year  = {2022},

date = {2022-10-10},

urldate = {2023-10-10},

booktitle = {PGIS Research Congress, 2022 (RESCON)},

volume = {2022},

number = {64},

pages = {14},

address = {Sri Lanka},

organization = {University of Peradeniya},

abstract = {Fish is a great source of protein, polyunsaturated fatty acids (PUFA), lipo-soluble vitamins, and essential minerals. Meanwhile, people who live in the dry zone of Sri Lanka consume inland fish species collected from irrigation reservoirs. Toxic metals tend to accumulate in fish; thus, it is important to investigate the safety of the consumption of inland fish. This study evaluated the toxic metal contamination status of the edible fish (Etroplus suratensis) in the Mahakanadarawa tank and assessed the risk of fish consumption. Mihintale Divisional Secretariat Division was identified as a major CKDu-prone area in the Anuradhapura District. Mahakanadarawa tank is a major fishing source in the area. Fifteen E. suratensis samples were collected from the Mahakanadarawa tank in April 2022. The fish muscle parts, gut, and gills were removed, stored in sterile polyethylene bags, and kept at 4°C during transport. The concentration of metal elements, including Mn, Co, As, Cd, Cr, Pb, Cu, Zn, Al, Fe, and Ni, was determined in an acid-digested sample using inductively coupled plasma mass spectrometry. The average contents of the nephrotoxic heavy metals/metalloids such as As, Cd, Pb, and Cr in the gut tissues of E. suratensis had reported elevated values compared to other tissue parts (gills and muscle). The average Pb content in the tissues of the gills, muscles, and gut of E. suratensis exceeded the permissible limits given by WHO/FAO. Average Cd contents did not exceed the permissible level in all analyzed tissue types, while average Zn and Cu levels have also complied with the WHO/FAO standard limits. The edible part of the fish consisted of an average of As = 0.01(±0.01) mg/kg, Cr = 0.22 (±0.03) mg/kg, Mn = 1.19 (± 0.36) mg/kg, and Al = 180.8 (±137.0) mg/kg. Even small amounts of toxic metals are reported in edible tissues of the E. suratensis; long-term consumption of fish may generate a negative health effect on consumers. Further risk assessment of toxic metals in E. suratensis in different reservoirs, including reference areas (CKDu-non-endemic areas), needs to be investigated in future studies.},

keywords = {CKDu, Contamination, E. suratensis;, Heavy metals, Inland Fish},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{sampath2022evaluation,

title = {Evaluation of toxic metal contamination in surface sediments and water in Mahakanadarawa tank; Anuradhapura, Sri Lanka},

author = {M Sampath and RT Perera and PLRA Perera and JA Liyanage and WAPJ Premaratne},

url = {https://www.researchgate.net/publication/364716334_Evaluation_of_toxic_metal_contamination_in_surface_sediments_and_water_in_Mahakanadarawa_tank_Anuradhapura_Sri_Lanka},

year  = {2022},

date = {2022-10-01},

urldate = {2022-01-01},

booktitle = {International Conference on Applied and Pure Sciences},

pages = {9},

publisher = {Faculty of Science, University of Kelaniya Sri Lanka},

abstract = {Toxic elements, including heavy metals/metalloids, readily contaminate water reservoirs via natural mechanisms such as surface runoff, precipitation, and atmospheric deposition. As a result, some toxic metals can be accumulated in surface sediments in the reservoirs and be incorporated into the food chains. It has become a major issue because various trace elements contaminate water, soil, and sediments, which can have serious health consequences due to their toxicity, persistence, and carcinogenic nature. This study was carried out with the aim of analysing the sediment quality in a major irrigation tank called Mahakanadarawa tank in Anuradhapura district, which is located in a high prevalence of chronic kidney disease of unknown etiology (CKDu) in Sri Lanka. Fifteen composite sediment samples (five samples in each of fifteen different locations) were randomly collected around the Mahakanadarawa tank in April (2022). Twenty surface water samples (Triplicated) were collected from the Mahakanadarawa lake using twenty different locations. Concentrations of metal elements including Mn, Co, As, Cd, Pb, Cu, Zn, Na, K, Al, Ca, Mg, Fe, and Ni were determined using inductively coupled plasma mass spectrometry (ICP-MS) and multi-element standards were used for the instrumental calibration. Statistical analysis was done using SPSS Statistics Software. According to the analysis of the sediment samples, none of the analysed toxic metals have exceeded the severe effect level as well as the lowest effect level. Abundancy of the metals in the sediments samples is varied as Fe> Mn > Cr> Zn > Cu >Pb > Ni >Co> As> Cd. The Igeo (Geo Accumulation value) values obtained, and the index values exhibit that the sediment samples have a tendency to transfer to an unpolluted to moderately polluted stage with analysed toxic metals except for Zn and Cd. Owing to the long-term intense applications of the crop fertilisers and pesticides in the area, toxic metals may be transferred and concentrated in the tanks from the agricultural fields. Apart from that, average concentrations values of analysed metals, including toxic metals such as Pb, As, and Cd in surface water, were far below the irrigation standards. Contamination of food chains and worsening the hazardous conditions for aquatic life can occur due to the toxic metal accumulations in the surface sediments. In order to conduct a health risk assessment for the consumption of tank fish from Mahakanadarawa tank, further studies should be performed by conducting several sampling cycles of sediment and water as well as toxic metal contamination status of inland fish in Mahakanadarawa tank also need to be evaluated.},

keywords = {ckd, CKDu, Contamination, Heavy metals, Sediment, Surface Water},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{mkjk2022bioaccumulation,

title = {Bioaccumulation of toxic metals in Oryza sativa grown in North Central Province in Sri Lanka},

author = {MKJK Kumari and WAPJ Premaratne and PLRA Perera and WPRT Perera and JA Liyanage},

url = {https://www.researchgate.net/publication/361999369_Bioaccumulation_of_toxic_metals_in_Oryza_sativa_grown_in_North_Central_Province_in_Sri_Lanka},

year  = {2022},

date = {2022-06-01},

urldate = {2022-01-01},

booktitle = {International Symposium on Agriculture and Environment(ISAE)},

volume = {2022},

pages = {32},

publisher = {University of Ruhuna, Sri Lanka},

abstract = {This study was carried out to assess the levels of heavy metals such as Arsenic (As), Cadmium (Cd), and Lead (Pb) in domestically grown rice sold in North Central Province (NCP) which is identified as a high CKDu prevalent area in Sri Lanka. Based on eight paddy areas, thirty Oryza sativa composite samples were collected in each selected Divisional Secretariat (DS) area in NCP. Samples were subjected to microwave digestion process and As, Cd and Pb analysis were carried out by the ICP-MS. The mean Pb levels in domestically grown rice were significantly higher than the FAO/WHO allowable limits (Pb-200 µg/kg) in most of the DS areas. Among selected DS areas, the Padaviya DS area has highlighted reporting 2815 µg/kg mean Pb content in the rice samples. However, none of the mean values of As and Cd in rice samples in selected areas have exceeded the FAO/WHO allowable limits (As-200 µg/kg, Cd-400 µg/kg). The Highest Cd contamination was reported in Higurakgoda and Padaviya DS areas and the values were 106.69 µg/kg, 105.69 µg/kg, respectively. The highest mean value of as was reported in the Kebithigollewa DS area and it was 49.75 µg/kg. The values of estimated daily intake (EDI) of the analyzed metals were also very far below than the Tolerable Daily Intake (TDI) (Pb-250 µg/day, Cd-62 µg/day, As-3 µg/day). Owing to high Pb content in domestically grown rice samples in selected areas, long term consumption of rice causes to accumulate the Pb in body tissues and generates a health risk of residents in selected CKDu affected areas in NCP.},

keywords = {CKDu, Contamination, Parbolic Rice, Toxic Metals},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{perera2021risk,

title = {Risk Assessment of Bioaccumulation of Toxic Metals in Rice Grains (Oryza sativa) in a CKDu Endemic Area; A Study in Mihintale Division, Sri Lanka},

author = {PLRA Perera and WPRT Perera and JA Liyanage},

url = {https://www.researchgate.net/publication/354193460_Risk_assessment_of_bioaccumulation_of_toxic_metals_in_rice_grains_Oryza_sativa_in_a_CKDu_endemic_area_A_study_in_Mihintale_division_Sri_Lanka},

year  = {2021},

date = {2021-08-01},

urldate = {2021-01-01},

booktitle = {Research Symposium of the Faculty of Allied Health Sciences - RuFARS},

publisher = {Faculty of Allied Health Sciences, University of Ruhuna, Galle, Sri Lanka},

abstract = {Background: Chronic Kidney Disease of unknown etiology (CKDu) is a heterogeneous disorder affecting kidney structure and its functions. CKDu has rapidly spread throughout Sri Lanka in the past two decades and has become predominant in the North Central Region. Food or water borne diseases are one of the key issues in food safety assurance in Sri Lanka. Pesticides and heavy metals play an important role in modern agriculture and food safety. Objective: To evaluate the toxic metal contamination status in the polished rice samples (BG 300) grown in the Maradankulama area. Methods: Maradankulama GN Division was selected based on the available information on medical/hospital records, which has the highest number of CKDu patients in the Mihintale Division as the sampling area. A survey protocol was also developed. Thirty polished rice samples (BG 300) were collected from the households subject to three paddy areas in the Maradankulama GN area according to the random stratified sampling method and heavy metal concentrations of rice samples (Chromium, Lead, Arsenic and Cadmium) were analyzed by ICP-MS. Results: The male CKDu patients were higher than females (Male, 57.15%; Female, 42.85%). All the CKDu patients subjected to the survey in the area belong to the farming community within the age group of 60-70 years. In Maradankulama Cr(7.268±0.046), Pb(1.923±0.209), As(0.064±0.009) and Cd(0.026±0.003) were detected in mg/kg levels. Among the analyzed metals in the rice samples, mean Cr and Pb contents have exceeded the maximum permissible level (MPL) according to the Codex Alimentarius commission guidelines. Conclusion: Arsenic and Cadmium contents in the rice samples were well below the Codex standard. However, rice samples have been contaminated with some nephrotoxic metals such as Chromium and Lead. Hence, long term exposure to the toxic metals may generate a risk for kidney damage in people.},

keywords = {CKDu, CODEX, Contamination, Oryza sativa, Toxic Metals},

pubstate = {published},

tppubtype = {inproceedings}

}