Arsenic poisoning: man-made disaster?

The suggestion he makes, right at the start of our meeting, is a dramatic one. Dr Jamal Anwar believes that if steps are not taken in the right direction very soon, arsenic contamination could threaten the very existence of our civilization. 'It seems dramatic to you because we have been led to believe that the danger from arsenic contamination has passed and what we need to do is take care of mitigation efforts. Well, that is not correct', he asserts. According to Dr Anwar, it has been generally accepted that arsenic contamination of our ground water is the result of a natural' phenomenon. "But my research shows that this is highly unlikely," he states. "Arsenic contamination is anthropogenic in Bangladesh i.e. it is caused by or influenced by human activities." A renowned geologist with vast experience in environmental studies, Dr Anwar's premise is that arsenic contamination in the ground water in Bangladesh is more than likely the result of indiscriminate use of sub-standard agrochemicals in the soil for some three to four decades from the start of the "Green Revolution" to this day. "

According to a premise put forward by a British Geological Survey, (BGS/MML 1998), arsenic came down from the Himalayas and was deposited in our soil some 18,000 years ago," Dr Anwar explains. This premise has been taken to be the most acceptable explanation of the origin of arsenic in Bangladesh over such a large portion of the country's groundwater source."I found this premise difficult to accept because the scientific evidence of geological conditions in Bangladesh some 18,000 years ago, as well as the soil conditions now, have led me to conclude otherwise. My research has challenged this premise conclusively," he states.

Dr Anwar, who is presently working with the Integrated Quality and Management (IQU) institute in Berlin, sets forth his own findings in great detail in a recently published book, "Arsenic Poisoning in Bangladesh:End of a civilization?" These findings are at times highly technical in nature and somewhat difficult for the layperson to grasp, but in essence they throw serious doubts on the assumption that Bangladesh has had arsenic in its soil for thousands of years because of a natural' set of circumstances. The arguments put forward by Dr Anwar reflect many questions already asked about arsenic. For instance, if it has been present for so many years, why is its presence being felt only now. Also, why is arsenic found in some groundwater sources, such as shallow tube wells, and not in deep tube wells? If the Himalayas are the source of the arsenic, why is it also found in the Chittagong Division? A reading of this work may not answer all these questions, but it will offer an alternative set of ideas and possibilities that should be taken seriously and what is more, should be investigated in much greater depth.

According to Dr Anwar's research, geological records of Bangladesh since 10.5 million years ago, to the present time do not show any abnormal concentration of arsenic. If arsenic had been dissolved by chemical and biological processes, every geological formation would show dissolved arsenic deep wells would be more contaminated than shallow wells and, if not contaminated, sediments would present arsenic contamination. If mobilisation of arsenic took place down the rivers and arsenic was adsorbed with iron, as claimed by the BGS report, then arsenic should be found in water with a high iron content, but this is not the case in Bangladesh.Dr Anwar states that other surveys, such as the German Geological Survey (BGR, 1996) indicate that the mass of snow and ice accumulated in the last glacial period in the Himalayas was small and in fact, the climate was drier in the subcontinent at that time. Therefore, it is difficult to visualise an increased rate of flushing that could have removed arsenic from the Himalayas and other terraced land into the deltaic region of Bangladesh.

Furthermore, there is little evidence of arsenic in the river-deposited silt in the Bay of Bengal. Furthermore, arsenic above the permissible level has been reported in the groundwater in Chittagong Division, he points out. "This area belongs to the Indo-Burman ranges, and geological and mineralogical investigation shows that the sources of sediments here are mainly river-transported sediments from the north-east. The premise of arsenic being sourced from the Himalayas to this area therefore is not convincing," he states. Anwar's research and vast experience in environmental studies and as a geologist led him to examine conditions in more recent times just four or five decades ago. "I have come to the conclusion that we need to examine the impact of agrochemicals on our soil I believe there is a strong link between agrochemicals and arsenic in the ground water. Indeed, I am convinced that arsenic occurs in Bangladesh not because of some "natural" phenomenon that happened thousands of years ago, but because of human activities in promoting the Green Revolution.

"The Green Revolution not only failed to actually produce more rice through its new high-yield varieties (the increase in production was the result of more land being brought under cultivation) but also, caused serious soil depletion, genetic erosion and by encouraging the use of fertilizers, could have eventually brought about arsenic contamination in Bangladesh," he states.In his recently published work, the German-based scholar presents comprehensive data to support his arguments. Dr Anwar contends that under the high-yielding "Green Revolution" technology, barrages were constructed without storage backing, thus diverting water in canal systems running hundreds of kilometres, without acknowledging the environmental impact. Besides a rapid increase in water-borne diseases, the new technology intensified chemical farming to increase yields. "Agriculture in Bangladesh is directly supported by chemical fertilizer production for which the World Bank has granted credit directly for fertilizer production, import, transportation and fertilizer industry rehabilitation," Dr Anwar explains.

He points out that while the total World Bank credit allocation for the fertilizer sector from 1973 to 1996 has been US$166 million, no checks and balances have been put into place to screen the fertilizers or to establish standards to protect Bangladesh from import of fertilizers that contain hazardous materials and/or are banned in the west. "In 1992, there was a well-reported case of some 6300 metric tonnes of fertilizers being imported to Bangladesh from the USA these were found to contain extremely hazardous heavy metal concentration a thousand times in excess of the allowable level," he discloses. Details of this case are contained in his book. The US company that produced the fertilizer was eventually penalised for mixing hazardous waste in the fertilizer, but some 4000 metric tonnes had already been distributed and farmers and consumers of the crop grown with these fertilizers in Bangladesh were never compensated, nor warned of the hazards in these products."There are no mechanisms in our country to control or monitor these chemicals instead their use has been encouraged as a means of enhancing our food output. But the price we may be paying for this usage is not being taken into account," he asserts."If you refer to my book you will see that I have traced in detail the nature and impact of agrochemicals chemical fertilizers, pesticides which are key components in the agricultural production system in our country. I have traced the differences between the west and the developing world, mainly how vulnerable Bangladesh continues to be in its indiscrimate and uncontrolled use of chemicals many of which would never be allowed to be used in their country of origin."Citing a report by the General Accounting Office of the US Congress, a reliable source of data and statistics, Dr Anwar says that 30 per cent of all pesticides exported from the United States are unregistered this means that they are not approved by the Federal Environmental Protection Agency (EPA) for use in the USA. Possibly the most significant factor that he cites, however, is the recent appearance of phosphate in the soil of Bangladesh.

"The soil in Bangladesh is poor in phosphate this is a known fact. So isn't it surprising that we find phosphate along with arsenic wherever arsenic is detected?" he asks. Dr Anwar refers to a study conducted in India in 1976 and cited in some detail in his book, that discovered arsenic concentration of 2 percent in super phosphate fertilizers in the UP. The findings were most alarming, he states, adding that if the same fertilizers have been used in Bangladesh then, of course, it is more than likely that our soil has been contaminated with arsenic. "As we all know, these days we are using fertilizers and pesticides that have no name unknown in origin and composition from across the border. We also already have problems of waste disposal in our country. I have described this in my book in some detail, how the safe disposal of solid wastes or by-products from fertilizer plants, for instance, have been a problem in the west. In Bangladesh, the problem has been noted by some experts, for instance, a report by Professor Khalilur Rahman of BUET, in 1992, claims that it is estimated that well over 22,00 CFT of packing material along with sludge has piled up. The arsenic control in the sludge is about 40 %. The process has since been modifed…but large quantities of solid materials remain dumped in concrete pits and in the open.'

Apart from these instances, there are many other instances, reported and unreported, that lead to the premise that there has been consistent chemical contamination of our soil, releasing arsenic into our system."There are other serious changes that have created an imbalance in our ecosystem, Dr Anwar claims. The traditional form of irrigation, the "overflow irrigation" system that gave the soil its required replenishment of nutrients and protected the farmer against flooding of a severe kind, has been replaced by a modern system that does not really benefit the farmer or the soil. The modern system with embankments prevents the normal run-off of monsoon waters and causes flooding, while preventing shallow flooding which farmers need to improve the quality of the soil and improve groundwater conditions during the dry season."In layman's terms, what we have is a total change in our agricultural system and this, together with the indiscriminate use of agrochemicals is causing serious problems a major problem being the catastrophic contamination by arsenic," Dr Anwar states. "The people of Dhaka have not been affected directly, because the situation is most severe in the rural areas," he adds. "Perhaps that is why there is a lack of awareness. But if steps are not taken soon, the food-chain will be contaminated and we will face a bigger catastrophy than we can visualise," he warns.

As a scholarly study, Dr Anwar's book is full of excellent raw material of immense value to all those who wish to know more about arsenic in Bangladesh. As a work of reference, it is praiseworthy, containing as it does meticulously researched and cross-referenced evidence of research papers, the author's own field studies, contemporary views and discussions, as well as several chapters dedicated to information on arsenic contamination, its impact on health and lesser known mitigation methods.If there is a drawback, it is a lack of editing and the presence of typographical inaccuracies. True, the aim has been to produce the work in as quick a time as possible, and the material collated and analysed is vast. But a second revised edition with substantial editing changes, would be welcome. The book is noteworthy because it contains a very thorough account and analysis of agrochemicals, with special reference to Bangladesh. The text is also supported by a glossary of terms that enable the layperson to grasp what are at times highly technical definitions and descriptions."Arsenic Poisoning in Bangladesh: End of a civilization?" provides comprehensive data on the likely origin of arsenic in Bangladesh not only as an academic exercise, but more significantly, with the aim of alerting us to the potential dangers that could still exist in our lives. The suggestion that agrochemicals could be responsible for the arsenic contamination of the ground water needs to be taken seriously, especially by institutions such as the World Bank which are promoting mitigation measures without necessarily focusing on the root cause of the problem. If ignored, the impact could well be as serious as Dr Anwar has visualised: at best, a serious threat to a civilisation, and at worst, its very end.

by Almas Zakiuddin