In this article, the current scientific evidence of Chronic Kidney disease with unknown aetiology... more In this article, the current scientific evidence of Chronic Kidney disease with unknown aetiology (CKDu), were critically reviewed and harnessed with other relevant literature with a view to justify the possible causative reason(s) for this chronic health problem. To this end, authors first reviewed the literature on socio-economic, environmental, meteorological, health and geo-environmental/chemical aspects in relation to the CKD of unknown aetiology in Sri Lanka and then studied the known aetiology of CKD (key medical facts) in detail highlighting a comprehensive list of causes. Based on the nature of economic development in the CKDu prevailing area, previous studies have suggested that the causative factor for CKDu is probably environmental and is related to the nature of anthropogenic activities. Therefore, authors investigated subject more into the chronic exposure to heavy metals associated with agricultural activities. Potential sources of heavy metals in the area are mention...
Methods for treating industrial wastewater containing heavy metals often involve technologies for... more Methods for treating industrial wastewater containing heavy metals often involve technologies for reduction of toxicity in order to meet technology-based treatment standards. This article was focused on the recently developed and newly applicable various treatment processes for the removal of heavy metals from industrial wastewater. Physico-chemical removal processes such as; adsorption on new adsorbents, ion exchange, membrane filtration, electrodialysis, reverse osmosis, ultrafiltration and photocatalysis were discussed. Their advantages and drawbacks in application were evaluated. In the processes of biological treatments microorganisms play a role of settling solids in the solution. Activated sludge, trickling filters, stabilization ponds are widely used for treating industrial wastewater. Bioadsorption is a new biological method and various low cost bioadsorbents (agricultural waste, forest waste, industrial waste, algae etc.) are used for maximum removal of heavy metals from w...
A laboratory study was done to evaluate the effects of binder on the physico-chemical properties ... more A laboratory study was done to evaluate the effects of binder on the physico-chemical properties and the quality of paracetamol tablets prepared by the wet granulation method using three different binders, namely, polyvinyl pyrrolidone (PVP), starch paste and gelatine solution. Tablets were evaluated for uniformity of weight and drug content, hardness & tensile strength, friability, disintegration time and dissolution rate. Results indicated that tablet weights measured for formulation 1, 2 & 3 were well within the ranges, (253.5 ± 12.7), (230.2 ± 17.3) and (238.1 ± 17.9) according to BP standard, respectively. Hardness, tensile strength, and disintegration time evidenced that the gelatine solution appeared to be the best for paracetamol tablet than PVP and starch paste. Friability and dissolution rates were not in agreement with other parameters. It was found that the strength of inter- and intragranular forces plays key role in maintaining quality of tables. All parameters are dep...
Unplanned Municipal Solid Waste (MSW) dumping is a serious problem in Sri Lanka especially becaus... more Unplanned Municipal Solid Waste (MSW) dumping is a serious problem in Sri Lanka especially because it contributes to water pollution as contamination by leachate. Humic Substances (HS) are highly toxic compounds and precursors of numerous chlorination by-products. To understand the role of HSs in water chemistry, it is necessary to isolate sufficient amounts of fractionated DOC. Limited data availability on DOC and suspended solids aggravates many difficulties in environmental studies. Present study was focused on quantification of solids and analysis of DOC fractions at landfill leachate in Gohagoda, Kandy. Collected leachate samples from four locations (one sample per each as GS1, GS2, GS3 and GS4) of the drainage channel were analyzed for TS, TSS, VS, VSS, TDS, SS and TOC. They were collected once per two weeks basis for a period of three months. A leachate sample (GS5) was obtained from the main dumpsite for analysis of DOC based on the Walkley and Black method. Humic acid ...
Abstract In the view of the above this research paper is aimed at presenting the results and fin... more Abstract In the view of the above this research paper is aimed at presenting the results and findings on the effects of all these developed agricultural practices, as well as over fertilization, on the surface water quality, shallow groundwater and deep groundwater ...
This paper compares the effects of adding fertilizer in nitrate pollution of groundwater in the U... more This paper compares the effects of adding fertilizer in nitrate pollution of groundwater in the Udunuwara area in Sri Lanka and the Shiroishi Plain in Japan. Excessive application of nitrogen fertilizers to soils contributes to contamination of groundwater by nitrates. As nitrate is one of the most identified contaminant in groundwater several environmental protection agencies maximum contamination level for nitrate is 10 mg/l as NO 3-N. The problem becomes severe in rural areas where people depend entirely on dug wells in the shallow groundwater table for their drinking water supply. Several locations were selected from the Udunuwara area of Sri Lanka for the detailed study. Nineteen shallow dug wells and 4 deep tube wells were selected for water sampling beginning of January to March 1998. Shiroishi Plain in Japan reclaimed from the Ariake Sea has a soil layer consisting of Ariake clay. The total 82 drug wells of average depth 1.5 m had been drilled around the area. Sample were collected in December 2000 and continued for one year around. Nitrate concentration in groundwater was measured by Cadmium reduction method. The results showed a varying nitrate distribution pattern compared to that the Udunuwara area. The effect of fertilizer application on groundwater depends on soil type, fertilizer type and amount used, crop type and climatic condition. The highly permeable soil around Udunuwara area showed that shallow groundwater is highly vulnerable for nitrate than the poorly drained soil of the Shiroishi Plain in Japan. As the people living in Shiroishi Plain use deep groundwater for domestic purposes, drinking water is safe (less than Maximum Contaminated Level for nitrate in drinking water for Japan-10 mg/l as NO 3-N) as far as the nitrate contamination is concerned. The results of these studies suggest that applying the correct rate of N fertilizer at the optimum time would have a substantial effect on reducing nitrate-N losses.
—Methods for treating industrial wastewater containing heavy metals often involve technologies fo... more —Methods for treating industrial wastewater containing heavy metals often involve technologies for reduction of toxicity in order to meet technology-based treatment standards. This article was focused on the recently developed and newly applicable various treatment processes for the removal of heavy metals from industrial wastewater. Physico-chemical removal processes such as; adsorption on new adsorbents, ion exchange, membrane filtration, electrodialysis, reverse osmosis, ultrafiltration and photocatalysis were discussed. Their advantages and drawbacks in application were evaluated. In the processes of biological treatments microorganisms play a role of settling solids in the solution. Activated sludge, trickling filters, stabilization ponds are widely used for treating industrial wastewater. Bioadsorption is a new biological method and various low cost bioadsorbents (agricultural waste, forest waste, industrial waste, algae etc.) are used for maximum removal of heavy metals from wastewater. Bioadsorption techniques are eco friendly best solutions for removing heavy metals from wastewater rather than physic-chemical methods. But chemical methods are most suitable treatments for toxic inorganic compounds produced from various industries which cannot removed from any biological and physical techniques.
— The quantity of waste adding to the mainstream can be simply reduced by home composting. During... more — The quantity of waste adding to the mainstream can be simply reduced by home composting. During the year 2007, the Central Environmental Authority, Sri Lanka has introduced compost bins to encourage the home composting and also they launched pilot projects in selected Local Authorities. This research was focused on the understanding of the effectiveness of the household composting bins as a waste management technique for household garbage. In this research, 70 household samples were selected randomly among the 4 Grama Niladhari Divisions in Gampaha Municipal Council Area and a questionnaire survey was carried out to understand the attitudes of the community towards the home composting and to identify the problems associate with the use of compost bin. During the survey to analyze the compost parameters, two compost samples were collected from the top and the bottom of the compost bin. The color, odor and texture of the compost samples were tested visually and the pH was measured by using a calibrated pH meter. Moisture content and the bulk densities were measured by oven dry method. Sieve test procedure was used to measure the particle size variation. Finally the collected data was analyzed statistically by using Minitab 14. According the results of the questionnaire survey, it showed the most widely used waste type was kitchen waste which is about 97% and about 66% of the compost bin owners add waste to their compost bin once a day. Also the finding stated that the most abundant problems associate with the use of compost bin was leachate problems (19%), unpleasant smell (13%) and worm problems (10%). The questionnaire survey indicated that the wastes disposed to the waste collection services were reduced 69% after introducing this technology among the people. Also the research findings revealed that there were no significant differences between the initial stage and the composting stage with respect to pH (Paired t test, P value=0.78), moisture content (Paired t test, P value=0.26), compact bulk densities (Wilcoxon Signed Rank test, P value=0.26) and loose densities (Wilcoxon Signed Rank test, P value=0.22) parameters. This was indicated that the efficiency of the compost bin was low on the basis of composting theories.
In this article, the current scientific evidence of Chronic Kidney disease with unknown aetiology... more In this article, the current scientific evidence of Chronic Kidney disease with unknown aetiology (CKDu), were critically reviewed and harnessed with other relevant literature with a view to justify the possible causative reason(s) for this chronic health problem. To this end, authors first reviewed the literature on socio-economic, environmental, meteorological, health and geo-environmental/chemical aspects in relation to the CKD of unknown aetiology in Sri Lanka and then studied the known aetiology of CKD (key medical facts) in detail highlighting a comprehensive list of causes. Based on the nature of economic development in the CKDu prevailing area, previous studies have suggested that the causative factor for CKDu is probably environmental and is related to the nature of anthropogenic activities. Therefore, authors investigated subject more into the chronic exposure to heavy metals associated with agricultural activities. Potential sources of heavy metals in the area are mention...
Methods for treating industrial wastewater containing heavy metals often involve technologies for... more Methods for treating industrial wastewater containing heavy metals often involve technologies for reduction of toxicity in order to meet technology-based treatment standards. This article was focused on the recently developed and newly applicable various treatment processes for the removal of heavy metals from industrial wastewater. Physico-chemical removal processes such as; adsorption on new adsorbents, ion exchange, membrane filtration, electrodialysis, reverse osmosis, ultrafiltration and photocatalysis were discussed. Their advantages and drawbacks in application were evaluated. In the processes of biological treatments microorganisms play a role of settling solids in the solution. Activated sludge, trickling filters, stabilization ponds are widely used for treating industrial wastewater. Bioadsorption is a new biological method and various low cost bioadsorbents (agricultural waste, forest waste, industrial waste, algae etc.) are used for maximum removal of heavy metals from w...
A laboratory study was done to evaluate the effects of binder on the physico-chemical properties ... more A laboratory study was done to evaluate the effects of binder on the physico-chemical properties and the quality of paracetamol tablets prepared by the wet granulation method using three different binders, namely, polyvinyl pyrrolidone (PVP), starch paste and gelatine solution. Tablets were evaluated for uniformity of weight and drug content, hardness & tensile strength, friability, disintegration time and dissolution rate. Results indicated that tablet weights measured for formulation 1, 2 & 3 were well within the ranges, (253.5 ± 12.7), (230.2 ± 17.3) and (238.1 ± 17.9) according to BP standard, respectively. Hardness, tensile strength, and disintegration time evidenced that the gelatine solution appeared to be the best for paracetamol tablet than PVP and starch paste. Friability and dissolution rates were not in agreement with other parameters. It was found that the strength of inter- and intragranular forces plays key role in maintaining quality of tables. All parameters are dep...
Unplanned Municipal Solid Waste (MSW) dumping is a serious problem in Sri Lanka especially becaus... more Unplanned Municipal Solid Waste (MSW) dumping is a serious problem in Sri Lanka especially because it contributes to water pollution as contamination by leachate. Humic Substances (HS) are highly toxic compounds and precursors of numerous chlorination by-products. To understand the role of HSs in water chemistry, it is necessary to isolate sufficient amounts of fractionated DOC. Limited data availability on DOC and suspended solids aggravates many difficulties in environmental studies. Present study was focused on quantification of solids and analysis of DOC fractions at landfill leachate in Gohagoda, Kandy. Collected leachate samples from four locations (one sample per each as GS1, GS2, GS3 and GS4) of the drainage channel were analyzed for TS, TSS, VS, VSS, TDS, SS and TOC. They were collected once per two weeks basis for a period of three months. A leachate sample (GS5) was obtained from the main dumpsite for analysis of DOC based on the Walkley and Black method. Humic acid ...
Abstract In the view of the above this research paper is aimed at presenting the results and fin... more Abstract In the view of the above this research paper is aimed at presenting the results and findings on the effects of all these developed agricultural practices, as well as over fertilization, on the surface water quality, shallow groundwater and deep groundwater ...
This paper compares the effects of adding fertilizer in nitrate pollution of groundwater in the U... more This paper compares the effects of adding fertilizer in nitrate pollution of groundwater in the Udunuwara area in Sri Lanka and the Shiroishi Plain in Japan. Excessive application of nitrogen fertilizers to soils contributes to contamination of groundwater by nitrates. As nitrate is one of the most identified contaminant in groundwater several environmental protection agencies maximum contamination level for nitrate is 10 mg/l as NO 3-N. The problem becomes severe in rural areas where people depend entirely on dug wells in the shallow groundwater table for their drinking water supply. Several locations were selected from the Udunuwara area of Sri Lanka for the detailed study. Nineteen shallow dug wells and 4 deep tube wells were selected for water sampling beginning of January to March 1998. Shiroishi Plain in Japan reclaimed from the Ariake Sea has a soil layer consisting of Ariake clay. The total 82 drug wells of average depth 1.5 m had been drilled around the area. Sample were collected in December 2000 and continued for one year around. Nitrate concentration in groundwater was measured by Cadmium reduction method. The results showed a varying nitrate distribution pattern compared to that the Udunuwara area. The effect of fertilizer application on groundwater depends on soil type, fertilizer type and amount used, crop type and climatic condition. The highly permeable soil around Udunuwara area showed that shallow groundwater is highly vulnerable for nitrate than the poorly drained soil of the Shiroishi Plain in Japan. As the people living in Shiroishi Plain use deep groundwater for domestic purposes, drinking water is safe (less than Maximum Contaminated Level for nitrate in drinking water for Japan-10 mg/l as NO 3-N) as far as the nitrate contamination is concerned. The results of these studies suggest that applying the correct rate of N fertilizer at the optimum time would have a substantial effect on reducing nitrate-N losses.
—Methods for treating industrial wastewater containing heavy metals often involve technologies fo... more —Methods for treating industrial wastewater containing heavy metals often involve technologies for reduction of toxicity in order to meet technology-based treatment standards. This article was focused on the recently developed and newly applicable various treatment processes for the removal of heavy metals from industrial wastewater. Physico-chemical removal processes such as; adsorption on new adsorbents, ion exchange, membrane filtration, electrodialysis, reverse osmosis, ultrafiltration and photocatalysis were discussed. Their advantages and drawbacks in application were evaluated. In the processes of biological treatments microorganisms play a role of settling solids in the solution. Activated sludge, trickling filters, stabilization ponds are widely used for treating industrial wastewater. Bioadsorption is a new biological method and various low cost bioadsorbents (agricultural waste, forest waste, industrial waste, algae etc.) are used for maximum removal of heavy metals from wastewater. Bioadsorption techniques are eco friendly best solutions for removing heavy metals from wastewater rather than physic-chemical methods. But chemical methods are most suitable treatments for toxic inorganic compounds produced from various industries which cannot removed from any biological and physical techniques.
— The quantity of waste adding to the mainstream can be simply reduced by home composting. During... more — The quantity of waste adding to the mainstream can be simply reduced by home composting. During the year 2007, the Central Environmental Authority, Sri Lanka has introduced compost bins to encourage the home composting and also they launched pilot projects in selected Local Authorities. This research was focused on the understanding of the effectiveness of the household composting bins as a waste management technique for household garbage. In this research, 70 household samples were selected randomly among the 4 Grama Niladhari Divisions in Gampaha Municipal Council Area and a questionnaire survey was carried out to understand the attitudes of the community towards the home composting and to identify the problems associate with the use of compost bin. During the survey to analyze the compost parameters, two compost samples were collected from the top and the bottom of the compost bin. The color, odor and texture of the compost samples were tested visually and the pH was measured by using a calibrated pH meter. Moisture content and the bulk densities were measured by oven dry method. Sieve test procedure was used to measure the particle size variation. Finally the collected data was analyzed statistically by using Minitab 14. According the results of the questionnaire survey, it showed the most widely used waste type was kitchen waste which is about 97% and about 66% of the compost bin owners add waste to their compost bin once a day. Also the finding stated that the most abundant problems associate with the use of compost bin was leachate problems (19%), unpleasant smell (13%) and worm problems (10%). The questionnaire survey indicated that the wastes disposed to the waste collection services were reduced 69% after introducing this technology among the people. Also the research findings revealed that there were no significant differences between the initial stage and the composting stage with respect to pH (Paired t test, P value=0.78), moisture content (Paired t test, P value=0.26), compact bulk densities (Wilcoxon Signed Rank test, P value=0.26) and loose densities (Wilcoxon Signed Rank test, P value=0.22) parameters. This was indicated that the efficiency of the compost bin was low on the basis of composting theories.
Uploads
Papers