More than a decade since the first cases of the fatal disease werereported, health experts are now blaming contaminated groundwater as the main cause.
The illness slowly destroys kidneys, making it impossible to get rid of body waste or excess water, eventually requiring dialysis or a transplant.
Wide areas of Sri Lanka’s North Central, Northern and Eastern provinces have recorded a high prevalence of chronic kidney disease in the last two decades. Recently published research by the New Delhi-based Centre for Science and Environment (CSE) estimated affected areas cover 17,000sqkm where 2.2 million people live.
These provinces are also the island’s main rice-producing regions. CSE found male farmers at highest risk with at least 15,000 currently affected.
From 2009-2011 in the north-central Anuradhapura District, health officials reported that the number of registered patients with chronic kidney disease diagnoses increased by 25 percent to 1,424. The district reported some 1,600 chronic kidney-disease-related deaths from 2003-2010.
CSE officials told IRIN that water consumption is high in the dry zone and likely to increase during droughts.
Research carried out in 2011 by Sri Lanka’s University of Peradeniya, Central Province, found the farmers most at risk spent long hours working alone without hired help.
Dhammika Dissanayake, a researcher at the university who co-authored the November 2011 report, said farmers sometimes spent 12 hours a day in extreme heat. “Field studies showed that they did not take enough water. If the temperatures are going up, the situation is likely to worsen.”
According to the Ministry of Environment, there were 1,400 reported droughts nationwide between 1985 and 2004, mainly in the dry zone, with the most severe being in 2001, 2004 and this year when the monsoon rains arrived almost one month later than usual. The country has two monsoons annually, with the next one expected to arrive in December and ending next March.
“[Farmers] need to take in more water to flush out the chemicals, but they don’t. Sometimes we just can’t imagine the extreme heat they work in,” Dissanayake added.
The water farmers are drinking is contaminated with high levels of calcium, fluoride and dissolved solids due, in part, to geography, CSE reported.
“High temperatures in Sri Lanka and long working hours in the paddy field mean that there is a high consumption of [contaminated] water, which is readily filtered by the kidney but not readily secreted by the renal tubules.”
According to the National Water Supply and Drainage Board, 80 percent of the population has access to “safe” water sources, but only 30 percent has access to piped water, which health experts say is safer than the more commonly used hand-dug wells.
Sri Lanka has been going through a severe dry spell since mid-April with temperatures in some of the areas reporting chronic kidney disease, including the north-central Pollonnaruwa District, reaching 34-35 Celsius. Though rains have arrived in the country’s south, they have yet to reach the central-northern dry zone.
“Temperatures are on the rise and will keep rising, even after this dry spell is over,” said Malika Wimalasooriya, head of the climate change unit at the Department of Meteorology, who attributed rising temperatures to changing global weather patterns.
The more extreme heat has sped up surface water evaporation and shrunk groundwater resources, he added.
Other researchers point to unregulated use of fertilizer and pesticide as causes. “But water is at the heart of the problem,” said Channa Jayasumana from the faculty of medicine at Rajarata University in North Central Province, who explained how farmers try to salvage heat-withered crops with often incorrectly used fertilizer and pesticide.
Since the leading causes of chronic kidney disease worldwide are diabetes and hypertension, the fact that doctors reported the cases in Sri Lanka’s dry zone as water-related makes comparisons with other outbreaks difficult, said CSE's deputy director, Chandra Bushan.
The closest comparison he noted is Balkan Endemic Nephropathy, a kidney disease (the causes of which remain unconfirmed) affecting farmers in parts of the former Yugoslavia. No new cases have been reported since the 1990s.
What to do?
Bushan calls for providing clean water through water purification units in the short term and piped water in the long term to the population at risk as well as improving medical facilities to handle kidney complications.
Though doctors conduct mobile clinics in high-risk areas, researchers say early detection is still weak overall. Treatment at government hospitals is free.
There are renal units at North Central Province’s main Anuradhapura Hospital, smaller units at two city hospitals in the province, a larger facility at Kandy hospital in neighbouring Central Province and a standalone national kidney unit in the capital, Colombo.
Jayasumana from Rajarata University told IRIN the government should regulate fertilizer and pesticide imports and use nationwide due to what he calls “rampant” unrestrained use of the products - an idea that has not received official backing.
On 22 August the Sri Lankan government announced it will begin distribution of water purification units in affected areas.
“The most effective way to curb the spread quickly would be to educate those at risk [on a regional level] on the dangers and the importance of water quality and water intake,” said Dissanayake.