Rajarata, administratively including the Anuradhapura and Polonnaruwa districts is hailed as the region bearing the legacy of Sri Lanka, not only with the nostalgia it retains from the golden ages of the country, but also as the heart of agriculture, ensuring a major portion of the food security of the entire nation. Not only does the vast reservoirs coming second only to oceans, giant pagodas scraping the sky and solid stone carvings depicting emotions of a living Buddha bear evidence to the skills of ancient residents of Rajarata, but the lush green paddy fields adding color to the parched grounds of dry zone proves the competency of Rajarata farmer kings as well.
This glory and riches, in addition to having been the two most flourishing kingdoms of the country, had always been the major target of a number of foreign invasions throughout the history of Sri Lanka. Having endured those enemy attacks in the history running back to more than 2500 years, Rajarata is now facing another deadly threat, which is proving to be trickier to combat than the foreign attacks in the history and that, is none other than the Chronic Kidney Disease of Unknown Etiology (CKDu).
According to results of research conducted by National Science Foundation of Sri Lanka in collaboration of WHO, the number of cases of chronic kidney failure and deaths caused as a result, reporting from several regions of Anuradhapura and Polonnaruwa districts has been unusually high since early nineties and are on the increase up to present. Not only Rajarata but certain areas of Uva province and Central Province have fallen under this curse. What makes this gradual loss of functioning of kidneys remarkable is the fact that its origin is unknown. Although usually the etiology of chronic kidney diseases yields to high blood pressure and diabetes mellitus, none of these causes being the root to the chronic kidney disease in Rajarata makes it more the enigmatic. It is that very enigma of this deadly menace costing the lives of many in Rajarata and other areas, which makes CKDu an issue of great national importance.
So far, experts in various fields have tried and are still deep in the process of unraveling the mystery of CKDu. The most popular trails they run behind are contamination by toxicants in agrochemicals, cyanobacteria toxins, long term exposure to sunlight and dehydration, fluoride concentration and water hardness etc. Although the authenticity of the link these parameters have with CKDu is highly debated, one fact which has a common link to all the above mentioned parameters shall shed some light over uncovering the truth about CKDu in Sri Lanka. That link is none other than, the culprit for many other global issues – Climate Change.
Climate Change has become such a mundane topic that many laymen know that it refers to drastic changes happening in several climatic parameters at a global scale. The most prominent aspect of climate change is the increase of global mean atmospheric temperatures due to increased emission of greenhouse gases, mainly CO2. Although at a glance climate change seems to be a long shot towards unraveling the mystery of CKDu, once a few missing jigsaw pieces are fitted, the big picture will nicely prove to be the blueprint in finding the etiology of CKDu.
The first missing piece can be found by focusing on which in the island which are mostly affected by CKDu. Rajarata coming on top of the list and other areas concerned are prominent agricultural areas of the country, with Rajarata claimed as the heart of paddy cultivation in the country. The excessive use of agrochemicals to get a higher yield as well as to cope with the threat posed by pests is a bitter truth involved with the paddy cultivation in Sri Lanka. Agrochemicals used in Sri Lanka include a cocktail of chemical compounds which has been proven by scientific research to be severe toxicants, affecting a number of organs in the human body, including kidneys. While excessive use of agrochemicals in paddy cultivation carried out in Rajarata and other areas of concern alone proves to be a possible root cause, climate change has a role to play in it in the enhancement of spread of CKDu.
A thumb rule of impacts of climate change is, ‘Dry areas getting drier, while wet areas getting wetter’ which happens as a result of prolonged dry seasons followed by intense periods of heavy rainfall. This is proven to be true if attention is paid to the climatic conditions that prevailed throughout the country during the past two-three years, especially in Rajarata area, which suffered from droughts which spanned for a greater part of the year. Those drought seasons were followed by bouts of intense rainfall, which included the rainfall of the entire year concentrated to one or two rainfall event, making the rains less frequent, but more intense. Intense dry periods cause toxicants in agrochemicals to retain deposited in soil for a longer period of time before being washed away. Longer the time the toxicants retain in soil, more concentrated they become during the dry season. In such a condition, when a heavy rainfall following the dry period, washes off this highly concentrated toxicants retained in soil, it all ends up in the watersheds in the surrounding. Life in Rajarata area, acclaimed as the Land of Reservoirs (Wewu Bandi Rajjya) has a strong bond with reservoirs which serves as a lifeline for people residing the area, involving all aspects regarding water such as bathing, drinking and irrigation for agriculture. That is why the highly concentrated toxicants ending up in nearby watersheds have the potential of having a severe impact on the human health of people in the area.
Another remarkable fact in this story is freshwater fish bred in reservoirs, commonly called tank fish (wewu malu) being a highly savored delicacy in Rajarata. Most of the toxicants washing into reservoirs do not just end up in the waters, but makes its way into bodies of all organisms inhabiting the those waters. Most of tank fish, which mainly include tilapia, are top predator species in the aquatic food chains prevailing in the reservoirs. As these toxicants make their way up along the food chains into flesh of tank fish, the concentration of toxicants increase in each step of the food chain, making the toxicant level entering the human body through consumption of the flesh of tank fish even greater than what enters the water.
On the other hand toxicants retaining in soil over a prolonged drought period, results in increased uptake of those by plants, especially those cultivated in the area, which is mainly rice. Rice being the staple food of the majority of Sri Lankan paves another path for toxicants to enter the bodies of humans, making way for the devil of CKDu into humans.
Toxicants are not the only suspect in the list of unraveling the mystery of etiology of CKDu. Intense heat resulting from climate change comes next. According to predictions made by Intergovernmental Panel for Climate Change (IPPC) the global mean atmospheric temperature is predicted to increase by 40C by 2100. Rajarata area is one of the regions in Sri Lanka in which highest temperatures are being recorded which at times goes up to 400C. Intense heat is nothing new for Sri Lankans inhabiting the sultry tropics. But the fact whether unusually intense heat in tropics occurring lately as a result of climate change has a role to play in the mysterious drama of CKDu is a question worthy of rising.
Farmers of Rajarata who are the most prominent among victims of CKDu are also a group who are being exposed to strong sunlight for a greater part of the day, while engaging in work in the agricultural fields. It costs a large amount of water from their bodies which can lead to intense dehydration. It does not need rocket science to link dehydration as a cause to chronic kidney failure, as kidneys are the major excretory organ, responsible for filtering water in the body while producing urine. The main job of kidney is to reabsorb the excess water and other useful ions and salts in the blood and eliminating the toxic excretory products diluted in water, in the form of urine. Dehydration cause more water to be lost from the body in the form of sweat, resulting in decreasing the amount of water excreted via kidneys causing urine to become more concentrated and kidneys shall need to exert an extra effort to reabsorb the little amount of water available while salts can become concentrated resulting in formation of kidney stones. This not only proves to be the root cause for cystitis (inflammation of urinary tract and bladder) but also chronic damage to kidneys. That is what makes residents of Rajarata, particularly farmers who are getting exposed to scorching sun resulting from increased temperatures due to climate change, become more prone to chronic kidney failure. Despite being habitually exposed to intense sunlight in a torrid area in a tropical country, farmers of Rajarata are still at high risk of dehydration for they are exposed to scorching sunlight for a greater part of the day and they seldom drink adequate water to compensate the amount lost from body due to heat. The susceptibility of farmers for CKDu increases with another habitual practice of farmers which involves drinking of water from the places that collect water flowing from paddy fields – wakkada, which are rich in agrochemicals washing down from paddy fields.
Acidification of waters as a result climate change is the third missing piece in completing the story of CKDu. Other than increase of global temperature, the other major aspect of climate change is the increase of CO2 levels in atmosphere which accounts for various reasons, mainly burning of fossil fuels. Being an acidic gas dissolution of CO2 cause waters to become acidic. This links up with another habitual practice of people of Rajarata areas to attack kidneys in a chronic manner. As mentioned earlier, people of Rajarata rely of reservoirs in the area for most of their daily activities and usually Aluminum containers are being used for carrying and storing water taken from reservoirs. Increased acidity of water cause increased solubility of Aluminium, resulting in increased entry of Aluminium ions to body along with drinking water, taking a sever toll on kidneys.
Though scientific research has not expanded enough yet to precisely prove that climate change has a finger in the pie of CKDu, once these missing pieces are linked up together with the thread of climate change, the tapestry hiding the secret code for unraveling the mystery of CKDu is nicely formed, which is more than sufficient to take action towards elimating the menace of CKDu. It is clear from the facts so far discussed, that erroneous habits unknowingly practices by laymen coupled with results of climate change have a significant role to play in elevation of the risk for CKDu. That is where following a precautionary principle is vital which should involve creating awareness regarding these facts among laymen residing the high risk areas, since taking action towards mitigation of climate change is a far cry for farmers in these remote areas.