From Ceylon Today 16 Oct 2014 Govt's agriculture policy, cause of CKD –Academics By Ravi Ladduwahetty three frontline university scientific experts blamed the government's agricultural policy as the cause for the Chronic Kidney disease which has engulfed the North Central Province and other geographical expanses of Sri Lanka.They attributed the use of excess and subsidized fertilizer as the cause, which flows down from the upcountry hills as Mahaweli waters and ends up in the paddy fields of the North Central Province and other areas, which areas now have a proliferation of the disease.Here, the three experts- University of Peradeniya Prof. Gamini Rajapaksa, former Director of Agriculture Dr. Chris Panabokke and founding Director of the Sugarcane Research Institute Dr. Nande Dharmawardena are in conversation with Ceylon Today.Th e difference between Chronic Kidney Disease (CKD) and Chronic Kidney Disease of Unknown Aetiology (CKDU) The kidney is the principle end organ which participates in the elimination of liquid waste from the blood and helps maintain osmo regulation of the body. Kidney disease that manifests when its well-recognized causes (for example, diabetes, hypertension, and so forth) are absent is called Chronic Kidney Disease of Unknown Aetiology (CKDU). Urine-albumin excretion above standard threshold is usually the early clinical warning of CKDU.
Poor planning and inconclusive reports
Unfortunately for Sri Lanka, speculators, non-scientists and newspaper columnists had a field day here on the subject while a plethora of studies carried out by various groups were besieged with poor planning, data gathering, required analytical skills, proper instrumentation and a wide knowledge on the subject areas under consideration, clouding the picture totally, spending millions of tax payer's money including those by the WHO and Ministry of Health here.
Groundwater Quality Atlas of Sri Lanka
One of the more systematic studies so far carried out is that by Prof. Tomonori Kawakami etal (2014) titled "Groundwater Quality Atlas of Sri Lanka" which fortunately has put a full stop to speculations on arsenic, cadmium, hardness of water and heavy metals in ground water. It implied fluoride as a contributing factor due to its incidence overlapping that of CKDU. But it failed to explain why some regions although having high fluoride do not have CKDU (for example Pulmoddai vs Medawachchiya; Ampara, Huruluwewa, Moneragala & Wellawaya). Hence, even if CKDU incidence overlaps the presence of fluoride, its presence does not imply CKDU. Studies elsewhere (for example, Rift valley in Ethiopia 2003) had found already that although 33% of the samples had high fluoride content but had no associated incidence of CKDU.
Thus it is evident that almost all the studies carried out on CKDU in Sri Lanka, tried to imply a known cause elsewhere in the world.
None dared to think out of the box prolonging the agony, making even the government panic with mounting costs, increasing CKDU burden, despair, hopelessness gripping horror stories from affected regions and national elections round the corner!
Scientific method and introductory facts on CKDU in SL
We trust this analysis using scientific methods will assist the authorities to bring lasting relief to the affected farming community in several farming areas in the country such as Girandurukotte in the Badulla District, Medawachchiya and Padaviya in the Anuradhapura District, Medirigiriya and Hingurakgoda in the Polonnaruwa District, Nickawewa in the Kurunegala District, where CKDU is prevalent (Figure 1).
Affected patients are mostly rice paddy farmers. The estimated age-standardized prevalence of the disease is 15%. According to the Ministry of Health, the estimated number of CKDU cases is 69,258 as of June 2014. Estimated death toll is 20,000.Affected patients were of age categories over 55 years. The age category is shifting towards younger ages. It has been predicted that even school children could be affected in the near future.
Main culprit is poor quality ground water
It is important to note that CKDU is absent in Anuradhapura and Polonnaruwa municipality areas where pipe borne water is available from National Water Supply & Drainage Board directly implying that main culprit is the poor quality ground water in the affected areas. Closer examination of main aquifer types in Sri Lanka shows that CKDU incidence overlaps regolith aquifer of hard rock region with small tank cascade. These dry zone metamorphic hard rock regolith aquifers are found in NCP, NWP, NP & SP regions of the country (Fig 2).
Regolith aquifer of hard rock region with small tank cascades in Anuradhapura and Polonnaruwa are affected by fertilizer runoff from Mahaweli system as well as intensive overuse of synthetic fertilisers in these areas, due to poor replenishment of their ground waters by fresh supplies caused by erratic weather patterns. Vavuniya and Hambantota have escaped this threatas yet as there are no feeder channels from high fertilizer runoff areas such as Mahaweli systems to those areas. Thus future irrigation schemes planned to divert waters from the hills to such areas
(for example Planned Uma Oya diversion to Hambantota) should carefully monitor water quality to prevent them acting as conduits of dissolved ions from excess synthetic fertilizers, their overuse and other sources polluting the hard rock regolith aquifer in those regions. Otherwise, CKDU is a distinct possibility in those areas too.
Proposed causal factors
CKDU is a disease of as yet unknown origin, which reared its ugly head first in the mid-1990s in the NCP. Since then, many causal factors such as fluoride from drinking water and in combination with aluminum in cooking pots/pans, cadmium in rice and fish, cadmium, iron and lead in reservoir waters, arsenic in hard waters and toxins from...
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...cyanobacteria and chemically impossible glyphosate-arsenic association were proposed by various workers here. Perhaps, the ionicity hypothesis of Professor Chandre Dharmawardena et al explains satisfactorily most of the available data on CKDU in Sri Lanka. (Environ. Geochem.Health vol 34 no 4 August 2014 on line edition).
Causal Factors of CKDU
All the available data on the subject up-to-date, since early fifties, when analyzed scientifically show that, main culprit is the high ionicity of NCP ground waters in certain areas together with dehydration/insufficient intake of potable water under hot sunny stressful work conditions and routine alcohol consumption habits of the farming community in place of potable water during long working hours in the sun together with changes in weather patterns especially higher day time temperature with erratic precipitation due to climate changes here have failed to replenish the high ionicity waters in regolith aquifers of the NCP as they are constantly replenished by high ionicity waters from Mahaweli channels as well as frequent oxidation-reduction of those regolith aquifers releasing increasing quantities of ions to water table in the area making even dug well waters in certain areas not within safe ionicity for human consumption. They all contribute synergistically to CKDU.
Speculators misleading the Government- root cause not eliminated
As basic sciences of CKDU root cause have been clouded by speculations, the latest being the glyphosate-Arsenic association which is chemically impossible in NCP soils, efforts of the government in eliminating the root cause of the problem is delayed as government is totally mislead by speculators. Since the root cause is not eliminated, NCP farming community in affected areas continue to suffer unnecessarily. In the meanwhile Dialysis, Kidney transplantation, Reverse Osmosis and supply of potable water have become thriving businesses for some.
CKDU could be eliminated by practicing good science
CKDU has become a roaring business for some and for others it has become a topic for cheap popularity while the poor farming community is at the receiving end of this great circus. CKDU which could be eliminated by practicing good science has come to be viewed as a terminal incurable disease; a disease of as yet unknown origin, and the latest threat is the imaginary association between one of the well-known, time-tested green plant specific weedicide used all over the world including Europe, USA and Australia known commonly as "Round up" or chemically as glyphosate and a metalloid called arsenic species, combination of which is not favoured chemically! It is very well known that glyphosate only acts on photosynthetic tissues, it inhibits Shikimic acid pathways specific to green plants as the key enzyme is located in the chloroplast ("green tissue") only.
It has no effect on animals and microbes even at concentration five times the recommended dose. Glyphosate is inactivated as soon as it comes in contact with soil or even water containing debris. Thus farmers are adviced to use clean water in their knapsap sprayers to avoid inactivation. If proponent of glyphosate-arsenic association knew geometry theorem called Reductio ad Absurdum of Euclid, he would touch neither glyphosate nor arsenic in CKDU context here. Thus hasty banning of glyphosate which has no connection to CKDU will not lessen the CKDU burden in the country, but certainly it would aggravate food production problems here.
Our country is blessed by Nature to have minimum levels of arsenic when compared to the same in the South East and South Asian countries. If the rice production is declined due to ill advised agriculture policy decisions such as glyphosate banning, country will be compelled to import increasing amounts of rice from other countries; rice grown in soils naturally containing excessive amounts of arsenic, such as those prevailing in Bangladesh, which would lead to many other health problems such as cancers as arsenic species are well known carcinogens (cancer causing agents).
Implications of Cadmium
According to WHO reports, large amounts of cadmium ions have been added to our soils from imported triple superphosphate (TSP) fertilizers. Some reports point to possibilities of high amounts of cadmium in rice, cereals, lotus roots and inland fish, but their validity is doubtful as subsequent analyses which are reproducible have shown that cadmium levels in those food stuffs are below the WHO recommended levels. "Groundwater Quality Atlas of Sri Lanka" by Prof. Kawakami et al (2014) show that the values for arsenic and cadmium are extremely low and way below the stipulated standards which implies that arsenic and cadmium in ground water have no relation to CKDU prevalence in SriLanka.
However, if ingested, cadmium ions use the body's built in mechanism to go to kidneys from the liver. It is possible that excessive dehydration would concentrate these toxic materials in the blood of hard working farmers and chronic exposure will accumulate ions such as cadmium which can certainly damage kidneys as proven in the case of ItaiItai disease prevailing in the Toyama Prefecture of Japan.
High Ionicity of drinking waters and protein denaturation by Hofmeister mechanism
One of the more conceivable hypotheses for CKDU is that several ions being collectively responsible for denaturing of proteins as given by the Hofmeister series where fluoride ion is at the top in anions and ammonium is at the top in cations. These ions are readily available in excess amounts which are much higher than WHO recommended levels in these drinking waters.
Mahaweli waters acting as
conduits
The accelerated Mahaweli Project also brings in dissolved synthetic fertilizers that are applied to tea and vegetable cultivations in increasing amounts in the hill-country leading to increased iconicity in these particular areas where fluoride and ions derived from fertilizer are also abundant. This distinguishes between the drinking water quality of this particular area from those of other paddy growing areas, such as Ampara and Hambantota, and other areas of the Island. Hot environmental conditions prevailing in these areas concentrate both the so called "non-toxic ions" and "toxic ions" which can contribute to CKDU. Dehydration of farmers due to hard work under hot sun and also due to alcohol some of them routinely consume, together with inadequate water intake, will concentrate everything in blood; both apparently non-toxic ions and nephrotoxic (toxic to kidneys) ions.
This proposal by Dharmawardene et al. (Chronic kidney disease of unknown aetiology and ground water iconicity: Study based on Sri Lanka, 14 August 2014 In: Environ. Geochem. Healthvolume 34, No 4, available on line) fits very well with the facts available on CKDU in SriLanka. As such, the excessive usage of contaminated fertilizer and dehydration should be the most likely causative factors of CKDU.
Dehydration
A recent study by fourteen scientists of USA suggests that dehydration aggressively activates some biochemical pathways and thereby produce excessive amounts of unwanted materials some of which are toxic to kidneys. This study further supports the fact that dehydration to be the most likely causative factor of CKDU. The authors of this highly reputed publication have very correctly identified that global warming leads to the emergence of new diseases. Their study is based on CKDU in Central America but they have recognized that there is a concern that kidney diseases are increasing in other hot agricultural countries such as Sri Lanka, India, Mexico, Ecuador and Egypt.
Conclusion
Attempts to link arsenic, cadmium, fluoride, algal toxins and glyphosate with CKDU in Sri Lanka are not only inconclusive but have no valid scientific basis as they cannot explain the CKDU data for Sri Lanka.
On the other hand, high incidence of CKDU in Sri Lanka is shown to correlate with the presence of irrigation works and rivers that bring-in nonpoint source fertilizer runoff from intensive agriculture regions using excessive amounts of cheap synthetic fertilizers. Increased iconicity of drinking waters due to fertilizer runoff into river systems, frequent redox processes in hard rock regolith aquifers in tank cascades releasing more ions into these waters due to erratic weather patterns have jointly caused the CKDU. The consequent chronic exposure to high iconicity in drinking ground water together with dehydration under hot conditions debilitates the kidneys leading to CKDU.
Recommendations
• Management of water-table in hard rock regolith aquifer
Management of water table in hard rock regolith aquifer to be within potable quality standard is the principle intervention required to eliminate the root cause of CKDU. In addition, educating farming community on adequate consumption of good quality drinking water, prevention of dehydration and alcoholism are the other salutary practices.
• Free availability of good quality drinking water supplies
Dehydration increases concentration of all ions in blood and speedily drives biochemical pathways generating species which are toxic to kidneys. As such, supply of good-quality drinking water for the CKDU endemic areas is mandatory to eradicate this disease.
• Immediate review of Agriculture and hill country farming policy.
Banning of excessive use of synthetic fertilizers and monitoring their use in hill country are important. Resorting to organic farming in hill country through crop livestock integration, use of fertilizer efficient varieties, restricting cultivations of hills and practicing intensive cultivation of plains, subsidizing organic fertilizer and the supply of good-quality drinking waters to the affected areas would contribute to permanent solutions to the problem of CKDU. As a short term measure, drinking water derived from reverse osmosis would be an immediate solution but it should not be the permanent solution. Regolith and Mahaweli channels should be constantly monitored for excessive fertilizer runoff.
