Your search found 5 records
1 Pavelic, Paul; Senaratna Sellamuttu, Sonali; Johnston, Robyn; McCartney, Matthew; Sotoukee, Touleelor; Balasubramanya, Soumya; Suhardiman, Diana; Lacombe, Guillaume; Douangsavanh, Somphasith; Joffre, O.; Latt, K.; Zan, A. K.; Thein, K.; Myint, A.; Cho, C.; Htut, Y. T. 2015. Integrated assessment of groundwater use for improving livelihoods in the dry zone of Myanmar. Colombo, Sri Lanka: International Water Management Institute (IWMI) 47p. (IWMI Research Report 164) [doi: https://doi.org/10.5337/2015.216]
(Location: IWMI HQ Call no: IWMI Record No: H047229)
(3 MB)
In the Dry Zone of Myanmar, improved access to water is widely acknowledged as being vital for livelihood enhancement and the general well-being of around 10 million people, most of whom depend on agriculture. Thus, expanding the sustainable use of groundwater is of great importance for socioeconomic development. According to this study, opportunities for accessing groundwater are generally good, and development of the resource has steadily increased over the years. However, there still appears to be good prospects for expanding groundwater use for irrigation, with a view to increasing agricultural production. Provision of affordable mechanical technologies for drilling wells and support with credit facilities to purchase small-capacity motorized pumps for irrigation could improve food security and livelihoods, where there is potential to expand groundwater use. Replenishable groundwater resources of the Dry Zone are likely to be less than previously thought. Thus, it is important to find the right balance between increasing development of the resource for enhanced irrigation, while also protecting its existing beneficial use for communities and the environment.
(Location: IWMI HQ Call no: e-copy only Record No: H048177)
Chronic kidney disease of unknown (āuā) cause (CKDu) is a growing public health concern in Sri Lanka. Prior research has hypothesized a link with drinking water quality, but rigorous studies are lacking. This study assesses the relationship between nephrotoxic elements (namely arsenic (As), cadmium (Cd), lead (Pb), and uranium (U)) in drinking water, and urine samples collected from individuals with and/or without CKDu in endemic areas, and from individuals without CKDu in nonendemic areas. All water samples ā from a variety of source types (i.e. shallow and deep wells, springs, piped and surface water) ā contained extremely low concentrations of nephrotoxic elements, and all were well below drinking water guideline values. Concentrations in individual urine samples were higher than, and uncorrelated with, those measured in drinking water, suggesting potential exposure from other sources. Mean urinary concentrations of these elements for individuals with clinically diagnosed CKDu were consistently lower than individuals without CKDu both in endemic and nonendemic areas. This likely stems from the inability of the kidney to excrete these toxic elements via urine in CKDu patients. Urinary concentrations of individuals were also found to be within the range of reference values measured in urine of healthy unexposed individuals from international biomonitoring studies, though these reference levels may not be safe for the Sri Lankan population. The results suggest that CKDu cannot be clearly linked with the presence of these contaminants in drinking water. There remains a need to investigate potential interactions of low doses of these elements (particularly Cd and As) with other risk factors that appear linked to CKDu, prior to developing public health strategies to address this illness.
(Location: IWMI HQ Call no: e-copy only Record No: H048450)
This paper provides an overview of policy responses to arsenic in groundwater in rural Bangladesh to assess their role and potential effectiveness in reducing exposure. With 97% of the country consuming groundwater for drinking, there is a continuing crisis of tens of millions of people exposed to elevated levels of arsenic. An examination of the number of people protected through two major remediation efforts suggests that recent progress may not be sufficient to keep up with the increasing population or to resolve the crisis during this century. Recent developments in remedial options are examined to identify their potential role in an evolving policy and research agenda. There appears to be growing agreement about future research and policy responses that can scale remedial options and make them widely accessible. These include: (1) the need for a reliable and affordable programme of arsenic testing and retesting; (2) attention to risks from other soluble contaminants and pathogens; (3) explicit priority setting across locations, time and to address fairness; and (4) development of value chains to ensure remedial options are supported over time.
(Location: IWMI HQ Call no: e-copy only Record No: H048490)
(1.60 MB)
The source of geogenic arsenic (As) contaminating a shallow aquifer in West Bengal was traced to fine-grained sediments deposited in an abandoned river channel. Along with As-bearing phases, these sediments contain 0.46% codeposited organic carbon. The release of As and the geochemistry of groundwater within the channel-fill deposits is investigated using a detailed mass balance model supported by aqueous, solid-phase, and mineralogical data. The model describes the evolution of groundwater chemistry along a flow path extending from its recharge in an abandoned channel pond, through the channel fill, to the underlying aquifer. Variations in groundwater composition are explained in terms of mineral weathering of host sediments driven by organic carbon decay. Arsenic is released through the reductive dissolution of goethite and the weathering of chlorite. Concomitantly, some As is sequestered in precipitating vivianite. These competing processes reach equilibrium deeper in the channel-fill sequence as groundwater As concentrations stabilize. The model yields estimates of mineral reaction (or precipitation) rates including rates of organic carbon oxidation (1.15 mmol C L21 a21 ) and net As release (4:5731024 mmol L21 a21 ). Fine-grained, slightly permeable, deposits such as channel fill containing reactive organic carbon and As-bearing goethite and phyllosilicates are centers of intense chemical weathering conducive to As mobilization.
(Location: IWMI HQ Call no: e-copy SF Record No: H049987)
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