{"id":45415,"date":"2015-07-08T22:36:55","date_gmt":"2015-07-09T04:36:55","guid":{"rendered":"http:\/\/www.lankaweb.com\/news\/items\/?p=45415"},"modified":"2015-07-08T15:34:45","modified_gmt":"2015-07-08T22:34:45","slug":"supplying-clean-drinking-water-to-the-rajarata-in-sri-lanka","status":"publish","type":"post","link":"https:\/\/www.lankaweb.com\/news\/items\/2015\/07\/08\/supplying-clean-drinking-water-to-the-rajarata-in-sri-lanka\/","title":{"rendered":"Supplying clean drinking water to the Rajarata in Sri Lanka."},"content":{"rendered":"

By Bodhi Dhanapala, Quebec, Canada<\/span><\/h2>\n

The north-central province (NCP) in Sri\u00a0 Lanka, encompassing much of the ancient Rajarata with its irrigation channels and tanks (weva),\u00a0 has been afflicted with a kidney disease that was first identified by Nephrologists circa 1992. These patients were not linked with such well-understood causes like having diabetes or hypertension. The disease was named chronic kidney disease of unknown aetiology (CKDU). Also, although the first cases appeared in the early nineties, its causes must have existed before, as the illness develops slowly. This threw back the roots of the illness to the debut of the Mahaweli project, i.e., the\u00a0 late 1970s. This period, and the earlier decade (following the eradication of Malaria) saw a rapid rise\u00a0 in population in this\u00a0 fragile dry-zone environment. The disease may even have existed in earlier times without being recognized.<\/p>\n

Theories about the cause of CKDU.<\/strong><\/p>\n

A comprehensive study of the illness was sponsored by the\u00a0 WHO and the NSF. It\u00a0 examined the\u00a0 recognized\u00a0 causes like\u00a0 toxic heavy metal pollutants like arsenic (As), cadmium (Cd), lead (Pb) etc., as well as pesticide residues, gender and life-styles.\u00a0 The WHO-study showed clearly that\u00a0 arsenic and other metal\u201d\u00a0 toxins, or pesticide residues like glyphosate were NOT\u00a0 present in the NCP water or the soil.<\/p>\n

Theories based on arsenic and other toxins had to be ruled out as several independent research groups (from Peradeniya, and from Japan etc.) confirmed the WHO-conclusion that\u00a0 metal toxins are absent even at the astonishingly low\u00a0 10 parts per billion level in the Rajarata water. However, a very small number of researchers like Dr. Jayasumana of the Rajarata University have adamantly maintained that arsenic enters into the body combined with glyphosate,\u00a0 and causes CKDU, even though neither arsenic, not glyophosate is found in the Rajarata water table. The\u00a0 arsenic people\u201d\u00a0 have the support of\u00a0 credulous religious activists who claim that even divine spirits have confirmed that CKDU arises from\u00a0 arsenic!\u00a0 Their vociferous, short-sighted approach to combating CKDU has been to call for\u00a0 a rapid ban on herbicides and fertilizers. In Sri Lanka.\u00a0 Politicians propelled by uninformed journalists who fan public fear have recently banned glyphosate, throwing the plantation sector into jeopardy. This action is similar to that of persons\u00a0 who take preventive medication\u201d against some disease even though\u00a0 blood tests show that they do not have the disease!<\/p>\n

Arsenic was detected in the WHO study in the hair and body organs of CKDU patients. According to a study by Nanayakkara et al., jointly with Tokyo university, the\u00a0 type of arsenic found in CKDU patients is identifiable with that found in dried fish. Healthy people reject such arsenic, but those with damaged kidneys bio-accumulate the arsenic and show up in bio-assays. Thus the arsenic accumulation is a result of bad kidneys rather than an initial cause.<\/p>\n

Focus on clean water.
\n<\/strong>
\nRajarata residents who consumed spring water, municipal piped water\u00a0 or flowing surface water (in rivers and tanks) are relatively free of CKDU . This prompted several researches to consider that the illness must be linked to drinking water,\u00a0 since the metals, herbicides, and other\u00a0 multi-factorial\u201d causes\u00a0 (like life-style, poor agro-chemical safety practices etc) cannot be the culprit\u201d since the first two are absent, while the life-styles and agro-chemical usage of these farmers are common to all (a multi-factorial set of all the usual causes has been claimed by Prof. Wimalawansa).<\/p>\n

This led to various proposals for the c ause of the disease, one of which\u00a0 is that the high ionicity (excessively high levels of certain salts which affect protein layers in the kidney) could be the cause of CKDU. This has the merit of not needing arsenic, Cd, or glyphosate as\u00a0 the causative agent, given that they\u00a0 are in fact NOT\u00a0 found in the Rajarata water at any significant levels. Irrespective of whether this ionicity idea (Prof. Dhamawardana et al) , and related ideas based on fluoride ions (Prof. Illeperuma et al)\u00a0\u00a0 etc., are\u00a0 correct or not, it is evident that the supply of clean water\u00a0 should be a very desirable step in eliminating CKDU. It has also been ascertained that the\u00a0 water in ground wells (rather than from rivers and tanks)\u00a0 have high electrical conductivities,\u00a0 showing that they have a lot of salts and a high ionicity, while not containing arsenic or glyphosate.<\/p>\n

How to provide clean water to NCP residents.<\/strong><\/p>\n

The above discussion\u00a0 suggests that it is\u00a0 desirable to use the water from rivers and tanks, and treat them at home or in community locations to bring the water to municipal standards,\u00a0 using simple low-cost methods which are appropriate for the\u00a0 affected rural villages\u00a0 of the Rajarata.\u00a0 Meanwhile, a number of NGOs have promoted the technology known as reverse osmosis\u201d (RO), where the contaminated water is forced through special membranes using high pressure pumps. The membranes allow clean water to pass through, retaining the salts and contaminants behind.\u00a0 This provides a high-tech turn-key\u201d solution, providing fully de-mineralized water. This technology is not cheap, even for affluent communities.\u00a0 However, RO is the only adequate method if the untreated water is salty. Water containing over 3.0 grams\/litre of salt is salty. Completely demineralized water (RO water) is normally\u00a0 remineralized\u00a0 to bring its hardness to about 200 mg of Ca-equivalents\/Liter to make the water palatable. It should also be\u00a0 chlorinated\u00a0 (as with municipal water) to ensure that no accidental bacterial contamination occurs. Many, but not all scientists,\u00a0 believe that such mineralization helps to reduce cardio-vascular diseases (see, e,g., the Wikipedia article on hardness). The proposal to put back a bit of the RO waste water to remineralize the RO water may be adequate for livestock, but certainly not for human consumption.<\/p>\n

However, very low-tech, extremely cheap methods are available for\u00a0 obtaining clean water from polluted fresh water where the remove of NaCl and full de-meneralization are not needed. Since the NCP waters are not high in\u00a0 NaCl\u00a0 (c.f.,Table I of Water Lanka, vol. 3, issue 3), we discuss two possible water-cleaning devices which are, in our opinion, adequate\u00a0 as they can deal with fluoride and many other toxins. The first is a simple domestic\u00a0 filter that can be assembled at home,\u00a0 which uses clean sand and granulated bleach (calcium hypochlorite),\u00a0 and optionally some activated charcoal.\u00a0 A family would need a bag of\u00a0 fine clean sand, and a small drum of calcium hypochlorite granules from a swimming-pool supplier. To last 3-4 months.\u00a0 About 25 liters (i.e., about 5 imperial gallons) of water are brought from a stream or\u00a0 tank (weva\u201d)\u00a0 each day and provide the drinking and cooking water for a family of five. This water is stored in a glass fish-tank\u201d and\u00a0 treated with about one spoon of swimming-pool grade granulated bleach. The chlorine in the bleach destroys the bacteria, algae, organic matter etc.. The resulting broken-down debris\u00a0 flocculate\u00a0 and sink to the bottom of the tank.\u00a0 Furthermore, the calcium hydroxide and calcium carbonate present in the bleach granules react with any fluorides, phosphates, (or arsenates)\u00a0 and precipitate them\u00a0 as insoluble calcium salts which are brought down with the rest of the debris. These processes work best when the pH of the water is maintained near 7.\u00a0 Even if some of this material remain as suspended matter, they are removed by the next stage where the water passes through a sand filter. The sand is held in a cloth bag lining the container and thrown out every two or three\u00a0 days.<\/p>\n

The water may be (optionally)\u00a0 brought into contact with (a cloth bag containing) activated charcoal (made at\u00a0 home from coconut shells, or purchased), and\u00a0 further\u00a0 refiltered (sand bed).\u00a0 The sand from the last stage can be used in the first stage to economize on sand.\u00a0 A method of making home-made\u201d activated charcoal from coconut shells, developed by\u00a0 scientists at\u00a0 Santa Clara University, California, USA\u00a0 may be found at\u00a0 http:\/\/library.queensu.ca\/ojs\/index.php\/ijsle\/article\/viewFile\/4244\/4344<\/a><\/p>\n

I also contacted a municipal water-works engineer in Quebec, Canada who suggested that commonly available swimming pool filtration technology can be used to construct filtration units that may be used to at least pre-treat (or fully treat) river water or\u00a0 weva\u201d\u00a0 water. It is easy to set up a 10, 000 gallon above-ground plastic pool and use it as the water container or storage tank. It is\u00a0 filled, when needed,\u00a0 from a stream containing contaminated water. The pool-tank\u201d is treated with the appropriate amount of calcium hypochlorite\u00a0 (determined using a drop of indicator in a test tube, available from pool supply stores\u00a0 to optimize\u00a0 the amount of bleach used), and the chlorine is allowed to act on the water. Once the algae, organic matter, and insoluble calcium salts have precipitated down (usually 24-48\u00a0 hours), the pump is turned on. This circulates the water thorough a\u00a0 sand-filtering system. As the sand gets clogged with the filtered debris, the pressure builds up. At that point a back-wash step is carried out to wash away the contamination and the filter is rejuvenated. This process is carried out till the water is clean, or using test papers and indicator solutions giving the pH, total solids, total chlorine etc. The back-washing process leads to a loss of about 10% of the good water produced by the unit.\u00a0 RO membranes also needs regular back-washing, and also looses a significant amount of the input water as the RO-waste water is\u00a0 unusable.<\/p>\n

The chlorination and filtration presented here will purify the water but it will not reduce the hardness of the water. However, as mentioned before, the hardness data seen in Table I of the Walter Lanka, vol. 3 reference given earlier suggest that river and tank waters in the Rajarata are hard but quite palatable. In any case, it is very easy to determined that the output water (collected in the pool tank\u201d) is palatable by drinking a bit of it. A detailed chemical assay (as done for municipal water) should be conducted as frequently as possible.<\/p>\n

Notice that we have not used activated charcoal in this pool-tank filter system. We feel that maintaining\u00a0 the stipulated amount of chlorine. Health\u00a0 guidelines state that The use of chlorine in the treatment of drinking water has virtually eliminated water borne diseases, because chlorine can kill or inactivate most micro-organisms commonly found in water. All drinking water supplies should be disinfected, unless specifically exempted by the responsible authority. …The health risks associated with disinfection byproducts are much less than the risks from consuming water that has not been adequately disinfected. Free chlorine concentrations in most Canadian drinking water distribution systems range from 0.04 to 2.0 mg\/L.\u201d<\/p>\n

The water delivered from a simple sand- filtration and chlorination system will run at a tiny fraction of the cost of high-tech RO plants, and will require minimal intervention. The sand in sand filters need not be replaced for several years. The filtration units for a 10,000 gallon installation would be less than $150! The chemicals, equipment and know-how needed for\u00a0 a pool-filtration type water system should be freely available in Sri Lanka because tourists hotels and resorts routine maintain swimming pools.<\/p>\n

It is sometimes suggested that the chlorine in the water should be removed and that its presence is mildly\u00a0 objectionable. However, the Walkerton tragedy, where accidental contamination at the output stage (this led to the death of 7 people and hospitalization of thousands) was due to lack of adequate chlorination. Water from RO plants and other large distribution units should also include a chlorination step.<\/p>\n

An important question that can be raised here is, what evidence do we have that this type of treatment of water is sufficient to eliminate CKDU? The main evidence we have is the fact that\u00a0 Anuradhapura municipality is NOT a CKDU- stricken locality. The municipal water used in Anuradhapura does not completely de-mineralize the water as is done in RO plants. While the methods used bu municipalities are more elaborate than what is described here, the filtered water obtained by the simple methods used here should produce a water similar to municipal water, and far more healthy than the highly contaminated\u00a0 water from grond wells consumed by residents in CKDU- affected areas.<\/p>\n

ITI scientists have also proposed water-filtration systems using a clay-filtration tablet.\u00a0 The tablets can be discarded when they get clogged, as back-wash may not be possible, unlike with a sand-filtration system. Chlorination and means to remove fluorides, phosphates etc., are not included in the ITI system.<\/p>\n

Collection of rain water has also been discussed by many people, and this should also be encouraged by supplying inexpensive water tanks to the people in the affected areas.<\/p>\n

In conclusion, we have explored a number of very simple and inexpensive water filtration devices that may be useful to rural people, and well within their technological and financial capacity.\u00a0 The high-tech RO units belong to another level of sophistication and the two technologies are complementary. The rationale for proposing such simple units is that many of the causative factors originally proposed for CKDU can now be ruled out. For instance, metal toxins,\u00a0 glyphosate,\u00a0 agro-chemical\u00a0 misuse, or poor lifestyles cannot be relevant since these are equivalent for people in a village using spring water and not contracting CKDU, or for people in an adjacent village who do not use spring water and end up with CKDU.\u00a0 Metal toxins, herbicides or chloro-carbons\u00a0 etc., are not detected even at 10 parts per billion levels and hence attempting to remove them is pointless. The simple methods proposed here do not require a re-mineralization process to make the water more palatable and more healthy. They automatically incorporate a chlorination step which is mandatory for\u00a0 community water distribution systems. Furthermore, these simple filtration systems can be set up using local technological competence.<\/p>\n","protected":false},"excerpt":{"rendered":"

By Bodhi Dhanapala, Quebec, Canada The north-central province (NCP) in Sri\u00a0 Lanka, encompassing much of the ancient Rajarata with its irrigation channels and tanks (weva),\u00a0 has been afflicted with a kidney disease that was first identified by Nephrologists circa 1992. These patients were not linked with such well-understood causes like having diabetes or hypertension. The […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12],"tags":[],"class_list":["post-45415","post","type-post","status-publish","format-standard","hentry","category-forum"],"_links":{"self":[{"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/posts\/45415","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/comments?post=45415"}],"version-history":[{"count":0,"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/posts\/45415\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/media?parent=45415"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/categories?post=45415"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lankaweb.com\/news\/items\/wp-json\/wp\/v2\/tags?post=45415"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}