Silent Spring “Headlines in the NEW YORK TIMES in July 1962 captured the national sentiments…. silent spring is now noisy summer… In the few months between the New Yorkers serialization of “silent spring” in June and its publication in book form that September Rachel Carson’s alarm touched off a national debate on the use of chemical pesticides, the responsibility of science and limits of technological progress…” – Linda Lear- introduction to Silent Spring.
“These chemicals are now stored in the bodies of the vast majority of human beings regardless of age. They occur in the mother’s milk and in the tissues of the unborn child.
All this has come about because of the sudden rise and prodigious growth of an industry for the production of manmade or synthetic chemicals with insecticidal properties. This industry is a child of the Second World War!
“What sets the new synthetic insecticides apart is their enormous biological potency. They have immune power not merely to poison but to enter into the most vital process of the body and change them in sinister and often deadly ways. They destroy the very enzymes whose function is to protect the body from harm, they block the oxidation process from which the body receives its energy, they prevent the normal functioning of various organs and they may initiate in certain cells the slow and irreversible change that leads to malignancy……” - Rachel Carson – Silent Spring
" Also it had been noted that selenium levels of people with CKDu were below the normal level and arsenic levels of their hair were higher when compared with that of healthy persons in the areas. "
Rachel Carson and her book Silent Spring paved the way for the modern environment movement in the U.S.A. and to ban DDT and other related synthetic chemicals which has destroyed living beings including pests. Now this silent spring is echoing in our North Central province. There prevails a deadly silence of a chronic kidney disease which has already killed hundreds of innocent poor farmers.
Chronic Kidney Disease of unknown etiology (Ckdu)
Kidney diseases are not a rarity in Sri Lanka. Diabetes, hypertension and other known causal factors contribute towards chronic kidney diseases. However, this new variety is called Chronic Kidney Disease of unknown or uncertain etiology (CKDu). It is the duty of our scientists to research and find out the underlying factors for this CKDu and concrete remedial action that need to be implemented by the policy makers and relevant officials. That would be the only responsible way through which the term ‘unknown’ or ‘uncertain’ could be eliminated.
It has been reported that hundreds of people are dying every year due to CKDu in the region. Over 10,000 serious patients are registered in government- owned hospitals. According to a WHO survey some 15 percent of the population living in the North Central Province (total population 1.3 million in 2012) is suffering from CKDu. More dangerously, it is now spreading to other areas like the North, Eastern, North-West and Uva provinces.
When the disease was identified decades ago, many scientists carried out studies to determine its root cause. Some scientists attributed it to the hardness of the water and the presence of concentration of fluoride in soil. Some others suggested it was due to nitrification of tank water and the growth of some kind of algae.
A section of researchers boldly claimed it was due to contamination of heavy metal and excessive use of chemical fertilizer and pesticides. A group of nonwestern academics suggested Cadmium (Cd) and Arsenic (As) were responsible for it as agro chemicals used in those areas contained Cd and As. There were counter arguments over the scientific methods adopted by the non-western academics and the rationale of deities having guided those academics to find the root cause of CKDu. Some others argued as to why areas like Hambantota, where same agro chemicals were being used, were not affected, if agro chemicals caused the disease.
In response to a request made by the Ministry of Health and the funds provided by the National Science Foundation (NSF) which comes under the purview of the Ministry of Technology and research, the WHO some time back carried out a survey and a research to ascertain matters related to prevalence and causative factors of CKDu in Sri Lanka and also its social, economic and productivity impact. The report which had been made public in 2012 generated much controversy. Among the key charges against it was its failure to pinpoint any known etiology for CKDu prevailing in the North Central Province. It was therefore treated as inconclusive.
Cabinet Sub Committees, Parliamentary Select Committees and scientist committees had been appointed and recommendations have been made. However, it is a pity to note that a powerful lobby within the polity of Sri Lanka had been trying to dilute the facts, data and conclusions made by WHO and 43 leading scientists who carried out the study.
This prompted me, as the Minister of Technology and Research to direct the National Science Foundation to convene a scientists’ forum with WHO experts in order to try and reach a consensus on this health hazard. At that meeting the country representative of the WHO, Dr. F.R.Mehta clearly explained the study and its findings.
According to Dr.Mehta, CKDu is prevalent in four provinces in the country viz North Western North Central, Eastern and Uva. Besides the southern part of the Northern Province – Vavuniya also can be included in this geographical range. Globally, CKD is prevalent in El Salvador, Nicaragua, Balkan countries, Bangladesh and Andra Pradesh in India and its victims are mostly from farmer communities that use synthetic chemicals excessively.
Correlation of factors
Dr. Mehta pointed out that the team of scientists had focused on heavy metal contamination of food, human body, water, soil and other environmental systems. They have found 15 percent of the population living in those areas was suffering from CKDu, with 16.8 % among females and 13.3 % among males. The team had categorized the patients into four grades according to the severity of the disease and had found advanced grades of its severity more among males and becoming higher with the rise in age in both sexes. Only 40 percent of CKD patients had fallen into the category of CKDu. However the hospital registers had not differentiated the CKD from CKDu and 20 percent of CKDu cases had been associated with respective family histories of kidney diseases.
" However, it is a pity to note that a powerful lobby within the polity of Sri Lanka had been trying to dilute the facts, data and conclusions made by the W.H.O. and 43 leading scientists who carried out the study. "
The test results had revealed that urine cadmium excretion of persons with CKDu was significantly higher when compared to that of healthy persons living in endemic areas. It also had been noted that that higher excretion of cadmium and arsenic of healthy persons living in endemic areas were more exposed to Cd and As.
Also it had been noted that selenium levels of people with CKDu were below the normal level and arsenic levels of their hair were higher when compared with that of healthy persons in the areas. Scientifically negative correlation of selenium and arsenic could be expected. Although maximum level of arsenic concentration in water was higher in endemic areas ( CKDu household ground water wells) ,it was not so with water from the Mahaweli irrigation channels or traditional tanks. Even in non-endemic areas Cd and As levels were found somewhat higher when compared with stipulated values.
The test results of weedicides and pesticides (maximum levels) show dangerous contamination of Cd, As and lead (Pb) in some brands. In the case of fertilizer, Cd and Pb levels (maximum) were found to be higher than the desired levels. Cadmium and lead contents in bone tissues of CKDu patients were higher than controllable levels. Pesticide and weedicide residues were also found in persons living in endemic areas.
According to Dr. Mehta, the WHO study concluded that there was a triple threat to the kidneys viz low levels of cadmium through the food chain, Concurrent exposure to arsenic and pesticide coupled with deficiency of selenium.
Discussion which followed Dr. Mehta’s presentation identified that the multifactorial nature of CKDu and hardness of water may catalyst the situation. Also, dangerous contamination of heavy metals and agrochemical residues may cause other diseases such as cancer and liver malfunctioning etc.
Food habits and tobacco and alcohol consumption may exaggerate the situation in endemic regions. Further studies need to be carried out to ascertain food contamination
Under these circumstances, scientists need not argue about the inconclusiveness of the WHO report. It may be in a bad format, but with methodically adopted data there is more than enough to take concrete action. As suggested by the Ministry of Agriculture stern action should be taken on synthetic chemicals used in agriculture. Stern action also should be taken on imported food items contaminated with synthetic chemicals. Importers of agro chemicals and chemically contaminated food would be a powerful lobby with certain political backing. However truth, nature and compassion are the ultimate power blocks that would standup for human kind.