Arsenic, Chronic Renal Failure and use of Rainwater

by Dr. C.S. Weeraratna

(July 20, Colombo, Sri Lanka Guardian) Recent communications in the electronic and print media in relation to Chronic Renal Failure (CRF), and arsenic highlighted a number of issues which need the attention of the public and the relevant authorities

1. Chronic Renal Failure ( CRF), also called Chronic Kidney Disease of unknown etiology (CKDUE) is widespread in the North Central Province, part of North Western and Uva provinces. This disease is characterized by a slow, progressive, asymptomatic development. Around 10,000 people, mainly in the three provinces indicated above are currently undergoing treatment for this disease. In 2005,the Anuradhapura Teaching Hospital alone recorded 742 live discharges and 140 deaths due to CRF.

2. According to separate studies carried out by a number of Sri Lankan Scientists, CRF is attributed to high levels of one or more chemicals (to make it simple let us call it X). Among X are cadmium (Cd) , fluoride, aluminum, toxins released by Blue Green Algae, Arsenic (As) , and Mercury (Hg). The actual causal factor/s of CRF is not yet proved scientifically. The elements such as As, Hg, Cd, and their compounds, and other compounds which are suspected to cause CRF, are present mostly as complex organic/inorganic compounds in soils, fertilizers and pesticides. To prove that X which causes CRF has come from a fertilizer or a pesticide, it is necessary to carry out studies using labeled fertilizer or pesticide containing the element/compound under study. Simply because rice or any other plant contains X, it does not necessarily mean that the X has come from a fertilizer/pesticide, because X can be present in the soil too.

3. Analytical studies carried out by the Dept. of Chemistry of Kelaniya University (KU) and Industrial Technological Institute (ITI) on some pesticides and rice indicate contradictory results, This shows that the methods of analysis followed by either KU or ITI are incorrect. They need to verify their analytical methods.

4. Electronic and media reports indicating the presence of Arsenic in rice is worrying many people of the country. Not only As but many other possible toxic elements/compounds may be present in food. Heavy metals such as lead, cadmium, zinc etc. may be present not only in inorganic fertilizers but also in organic fertilizers made from solid wastes, which some are promoting. We hear/read about incidences of food toxicity in Sri Lanka, affecting a large number of students in schools, and workers in factories. The toxic elements/compounds present in food may not cause any harm if it is not absorbed into the system. However, if a pesticide is proved to contain high levels of X, it should not be applied as it could increase the level of X in the soil and hence in the plant products.

5. Authors of some articles in the electronic and print media, appear to be of the opinion that we need not use chemical fertilizers (Fs) and pesticides (Ps), because in the past these were not used in crop production. Of course it is best if we can produce crops without using Fs and Ps. Use of these Fs and Ps cause environmental pollution and tend to increase COP. All Pesticides are toxic compounds. Toxicity is indicated by what is called LD 50 values. Those of low LD values are more toxic than others. Although Fs and Ps were not used a few decades ago, the biotic environment including the level of the fertility of soils is not the same as was in the past, resulting in the need to use these Fs and Ps. New pests (insects, microorganisms etc.) keep on developing and unless these are effectively controlled, there could be food shortages. There may be a few plots cultivated without Fs and Ps using modified/different agronomic/spiritual methods. It is necessary to find out how effective these methods are. If they are effective, the researchers of the Dep. of Agriculture need to make recommendations based on their findings. It is also necessary that Integrated Pest Management (IPM) methods are developed and applied so that we could give up the use of synthetic toxic chemicals to control pests. In countries such as India, pests ate controlled mostly using IPM.

6. The most important issue not addressed effectively up to now is the fact that thousands of people, mainly from the Dry Zone have died/become disabled as a result of CRF. While the scientists try to find out the causal factor/s of CRF, it is extremely important that action is taken to reduce the occurrence of CRF. It is clear that CRF is caused by a toxic X in water. There is a need for a comprehensive public health effort to effectively address the problem of CRF which should be taken as a National Priority with the main responsibility resting on the Ministry of Health (MOH) . It is surprising why the MOH appear to be inactive on the issue of CRF. The findings of the research programme which is supposed to have been initiated by the Ministry of Health, in October 2008 are yet to be made public. The final report of this study was expected to be submitted in Dec. 2009. MOH needs to implement an integrated programme in association with other responsible authorities such as Ministries of Agriculture, Science and Technology, Education, Water Resources and the relevant provincial ministries to prevent/control the occurrence of CRF which is considered to be the third leading cause of death in North Central Province.

A relatively easy way of controlling /preventing CRF is making available good quality potable water. Rainwater is relatively the most pure form of water. It is almost free of toxic elements/compounds. A considerable portion of the rainwater that falls on the roofs of buildings can be collected in tanks in the premises itself. Water that falls on a roof of 1,000 sq m in an area where the average annual rainfall is 2,000 mm, would be around 2,000 cubic meters (i.e 2 million liters or app. 400,000 gallons). Water thus collected would be free of toxic substances and could be used for numerous domestic purposes including drinking.