The New Nation - Internet Edition

Climate change and human health

Md. Tareq Mahmud

Human health, incorporating physical, social and psychological well-being, depends on an adequate supply of potable water and a safe environment. Human beings are exposed to climate change directly through weather patterns (more intense and frequent extreme events), and indirectly through changes in water, air, food quality and quantity, ecosystems, agriculture, livelihoods and infrastmcture. Due to the very large number of people that may be affected, malnutrition and water scarcity may be the most important health consequences of climate change. Population health has improved remarkably over the last 50 years, but substantial inequalities in health persist within and between countries. The Millennium Development Goal (MDG) of reducing the mortality rate in children aged under 5 years old by two-thirds by 2015 is unlikely to be reached in some developing countries. Poor health increases vulnerability and reduces the capacity of individuals and groups to adapt to climate change. Populations with high rates of disease and disability cope less successfully with stresses of all kinds, including those related to climate change.

The World Health Organization (WHO) and UNICEF Joint Monitoring programme currently estimates that 1.1 billion people (17% of the global population) lack access to water resources, where access is defined as the availability of at least 20 litres of water per person per day from an improved water source within a distance of 1 km. An improved water source is one that provides 'safe' water, such as a household connection or a bore hole. Nearly two-thirds of the people without access are in Asia. In sub-Saharan Africa, 42% of the population is without access to improved water. The WHO estimates that the total burden of disease due to inadequate water supply, and poor sanitation and hygiene, is 1.7 million deaths per year. Health outcomes related to water supply and sanitation are a focal point of concern for climate change in many countries. In vulnerable regions, the concentration of risks from both food and water insecurity can make the impact of any weather extreme (for example, flood and drought) particularly severe for the households affected.

Changes in climate extremes have the potential to cause severe impacts on human health. Flooding is expected to become more severe with climate change, and this will have implications for human health. Vulnerability to flooding is reduced when the infrastructure is in place to remove solid waste, manage waste water, and supply potable water. Lack of water for hygiene is currently responsible for a significant burden of disease worldwide. A small and unquantified proportion of this burden can be attributed to climate variability or climate exh·emes. 'Water scarcity' is associated with multiple adverse health outcomes, including diseases associated with water contaminated with faecal and other hazardous substances (e.g., parasites). Childhood mortality and morbidity due to diarrhea in lowincome countries, especially in sub-Saharan Africa, remains high despite improvements in care and the use of oral rehydration therapy.

Climate change is expected to increase water scarcity, but it is difficult to assess what this means at the household level for the availability of water, and therefore for health and hygiene. There is a lack of information linking largescale modelling of climate change to small-scale impacts at the population or household level. Furthermore, any assessments of future health impacts via changes in water availability need to take into account future improvements in access to 'safe' water.

The relationship between rainfall, river flow and contamination of the water supply is highly complex, as discussed below both for piped water supplies and for direct contact with surface waters. If river flows are reduced as a consequence of less rainfall, then their ability to dilute effluent is also reduced leading to increased pathogen or chemical loading. This could represent an increase in human exposures or, in places with piped water supplies, an increased challenge to water treatment plants. Durirg the dry summer of 2003, low flows in the Netherlands resulted in apparent changes in water quality (Senhorst and Zwolsman, 2005). The marked seasonality of cholera outbreaks in the Amazon was associated with low river flow in the dry season (Gerolomo and Penna, 1999), probably due to high pathogen concentrations in pools.

Drainage and storm water management is important in low income urban communities, as blocked drains can cause flooding and increased transmission of vector-borne diseases (Parkinson; and Butler, 2005). Cities with combined sewer overflows can experience increased sewage contamination during 'flood events. In high-income countries, rainfall and runoff events may increase the total microbial load in watercourses and drinking water reservoirs, although the linkage to cases of human disease is less certain because the concentration of contaminants is diluted. The seasonal contamination of surface water in early spring in North America and Europe may explain some of the seasonality in sporadic cases of water-borne diseases such as cryptosporidiosis and campylobacteriosis. A significant proportion of notified water-borne disease outbreaks are related to heavy precipitation events, often in conjunction with treatment failures.

Freshwater harmful algal blooms (HABs) produce toxins that can cause human diseases. The occurrence of such blooms in surface waters (rives and lakes) may increase due to higher temperatures. However, the threat to human health is very low, as direct contact with blooms is generally restricted. There is a low risk of contamination of water supplies with algal toxins but the implications for human health are uncertain. In areas with poor water supply infrastructure, the transmission of enteric pathogens peaks during the rainy season. In addition, higher temperatures were found to be associated with increased episodes of diarrhoeal disease (Checkley et al., 2000; Singh et aI., 2001; Vasilev, 2003; Lama et aI., 2004). The underlying incidence of these diseases is associated with poor hygiene and lack of access to safe water.

The previous sections have described how climate change will affect the risk of water-related disasters, including glacial lake outburst floods (GLOFs), increased storm surge intensity, andchanges in flood risk including flash flooding and urban flooding, with some reductions in risk of spring snowmelt floods. [WGII 3.4.3] Floods have a considerable impact on health both in terms of number of deaths and disease burden, and also in terms of damage to the health infrastructure. While the risk of infectious disease following flooding is generally low in high-income countries, populations with poor infrastructure and high burdens of infectious disease often experience increased rates of diarrhoeal diseases after flood events. There is increasing evidence of the impact that climate-related disasters have on mental health, with people who have suffered the effects of floods experiencing long-term anxiety and depression.

Flooding and heavy rainfall may lead to contamination of water with chemicals, heavy metals or other hazardous substances, either from storage or from chemicals already in the environment (e.g., pesticides). Increases in both population density and industrial development in areas subject to natural disasters increase both the probability of future disasters and the potential for mass human exposure to hazardous materialsduring these events.

For a few infectious diseases, there is an established rainfall association that is not related to the consumption of drinkingwater (quality or quantity) or arthropod vectors.

The spatial distribution, intensity and seasonality of meningococcal (epidemic) meningitis in the Sahelian region of Africa is related to climatic and environmental factors, particularly drought, although the causal mechanism is not well understood. The geographical distribution of meningitis has expanded in West Africa in recent years, which may be attributable to environmental change driven both by land-use changes and by regional climate change.

Windblown dust originating in desert regions of Africa, the Arabian Peninsula, Mongolia, cenh'al Asia and China can affect air quality and population health in distant areas. When compared with non-dust weather conditions, dust can carry large concentrations of respirable particles; trace elements that can affect human health; fungal spores; and bacteria.

Climate influences the spatial distribution, intensity of transmission, and seasonality of diseases transmitted by vectors (e.g., malaria) and diseases that have water snails as an intermediate host (e.g., schistosomiasis). During droughts, mosquito activity is reduced but, if transmission drops significantly, the population of non-immune individuals may increase. In the long term, the incidence of mosquito-borne diseases such as malaria decreases because mosquito abundance is reduced, although epidemics may still occur when suitable climate conditions occur. The distribution of schistosomiasis, a water-related parasitic disease with aquatic snails as intermediate hosts, is influenced by climate factors in some locations, For example, the observed change in the distribution of schistosomiasis in China over the past decade may in part reflect the recent warming trend. Irrigation schemes have also been shown to increase the incidence of schistosomiasis, when appropriate control measures are not implemented.

Climate change and different sorts of human diseases are related to each other. So we should aware about climate change. International Panel on Climate Change (IPCC) should take proper initiatives and measures to combat with climate change and protect human health.

(The writer is of the Dept. of environmental science and resource management Mawlana Bhashani Science & Technology University, Santosh, Tangail)

The global water situation

Manir Hossain

Water is not distributed evenly over the globe. Fewer than 10 countries possess 60% of the world's available fresh water supply: Brazil, Russia, China, Canada, Indonesia, U.S., India, Columbia and the Democratic Republic of Congo. However, local variations within countries can be highly significant.

Less than 3% of the world's water is fresh - the rest is seawater and undrinkable.

Of this 3% over 2.5% is frozen, locked up in Antarctica, the Arctic and glaciers, and not available to man and 0.5% Fresh water available.

Thus humanity must rely on this 0.5% for all of man's and ecosystem's fresh water needs.

10,000,000 km3 stored in underground aquifers. Since 1950 there has been a rapid expansion of groundwater exploitation providing: 50% of all drinking water; 40% of industrial water; and 20% of irrigation water. 119,000 km3 net of rainfall falling on land after accounting for evaporation.

91,000 km3 in natural lakes.

Over 5,000 km3 in man made storage facilities reservoirs. There has been a 7 fold increase in global storage capacity since 1950.

2,120 km3 in rivers - constantly replaced from rainfall and melting snow and ice.

As farmers, industry and people take too much water there is nothing left for nature. The concept of water stress is relatively simple: it applies to situations where there is not enough water for all uses, whether agricultural, industrial or domestic. Defining thresholds for stress in terms of available water per capita is more complex, however, entailing assumptions about water use and its efficiency. Nevertheless, it has been proposed that when annual per capita renewable freshwater availability is less than 1,700 cubic meters, countries begin to experience periodic or regular water stress. Below 1,000 cubic meters, water scarcity begins to hamper economic development and human health and well-being.

The four ways people contribute to water stress as follows-

1. Excessive withdrawal from surface waters: Over the past 30 years, the Aral Sea in the former Soviet Union has shrunk to less than half of its original size. The demise of the Aral Sea was caused primarily by the diversion of the inflowing Amu Dar'ya and Syr Dar'ya rivers to irrigate water-intensive cotton and rice crops. This graphic shows the disappearance of the Aral Sea from 1957 to 2001. By 1987, about 60% of the Aral Sea's volume had been lost, its depth had declined by 14 meters, and its salt concentration had doubled.

2. Excessive withdrawal of water from underground aquifers: Along much of the west coast of India excessive fresh water abstraction has allowed sea water to enter aquifers thereby making the water so saline that it is unfit for human use. These consequences have been compounded due to excess irrigation water containing fertilizers and pesticides leaching into these aquifers.

3. Pollution of fresh water resources: Pollution can be so severe that the fresh water is no longer useable without incurring unacceptably high clean up costs. Pollution from many small paper mills using outdated technology has depleted the oxygen from the several river stretches in China, making them unfit for consumption by any form of life. China entered into a joint venture with a Finnish company to build a state of the art paper mill. China then closed the polluting firms and these rivers are making a remarkable recovery.

4. Inefficient use of freshwater: Poor irrigation practices, leakage in water delivery systems, inefficient use by industry and excessive consumption by individuals can all contribute to water stress. (Ref.: "Water for People, Water for Life" United Nations World Water Development Report, UNESCO, 2003. www.unesdoc.unesco.org)

(Manir Hossain is the President of Society for Environment and Nature Study (SENS) at Mawlana Bhashani Science and Technology University, Tangail. Email: Manir_nir@yahoo.com )

Rock structures planned to reclaim beaches

Arnab Pratim Dutta

On July 31, an expert committee of the Indian union ministry of environment and forest decided not to recommend the construction of rock structures designed to reclaim Puducherry's beaches from the sea. The committee has deferred its consent till there are proper studies on these structures-called groynes in engineering parlance. Puducherry's public works department has proposed the construction of groynes, but a group of activists from the union territory had petitioned the environment ministry against the proposal.

Construction of hydraulic structures was an unscientific way of tackling coastal erosion, they contended.

Coastal erosion is a serious problem in Puducherry. But the beaches did not disappear overnight. The problem began in 1989, when a harbour was built at the southern tip of the union territory. Two breakwaters were constructed as a part of the harbour which stopped the littoral drift, the natural south to north movement of sand.

The country's eastern cost has a high littoral drift with an estimated 6 million cubic metres of sand moving south to north along the coast. The breakwaters in southern Puducherry meant that sand from the beaches of the state moved north but there was no sand to replenish it. So the area north of the breakwater lost all beaches.

Consulting Engineer Services, a New Delhi organization which designed the harbour, had anticipated this problem. It had incorporated a sand bypass system in the harbour's design to obviate sea erosion: silt from the harbour would be dredged and artificially pumped to the other side, restoring the movement of sediments along the coast. Says M D Kudale, chief research officer of Central Water and Power Research Station (CWPRS), " a sand bypass system was put in place but seldom used except for a brief period between 2000 and 2001, when small stretches of beach began to reappear. But the system was discarded in 2002, and the beaches disappeared once again."

By 2002, Northern Puducherry had lost all sand. Structures along the coast began to crumble as sea water intruded into their foundation. In 2002-2003, the state government decided to build a seven km long seawall consisting of boulders along the coast. Rs 40 crore were spent on the construction. While Puducherry was saved temporarily, the problem of erosion was transferred to villages in Tamil Nadu in the north.

By 2006-end, areas in the state north of Puducherry had lost 200 metres of beach and the sea waves destroyed a few houses and killed a child. The Tamil Nadu government had to fortify these villages with a seawall. Meanwhile, in 2002, experts from the Indian Institute of Technology Chennai and the National Institute of Ocean Technology (NIOT) suggested that groynes be erected on a trial basis in Puducherry. Civil society groups like Indian National Trust for Art and Cultural Heritage and Citizens Forum For Puducherry opposed the move, contending that groynes would only transfer the problem of erosion towards the north of the structures-much like the breakwaters. The issue was raised in the union territory's legislative assembly in 2002. The government had then assured that it would seek a second opinion on the subject. It decided to seek the opinion of the Danish Hydraulics Institute (DHI), a Delhi-based consultancy . In June 2004, Z S Tarapore, a consulting engineer with DHI and a former director of CWPRS warned the Puducherry government against building groynes.

Tarapore, who had studied the site in 2002 at the behest of Puducherry's public work's department, wrote: "There were proposals to protect the coastt by two trial greyness, to protect this critical reach. I had pointed out that this was a dangerous proposition since the greyness would only transfer the problem further down-drift, where there are heavily populated areas." Tarapore also wrote that the government must conduct a "morphological" study before manipulating the shoreline.

He was not the first to warn. In 1978, before work on the harbour had begun, CWPRS had carried out a study which suggested a sand bypass system once the harbour was built.

On November 3, 2007, a consultation entitled "Restoration and Protection of Pondicherry-Tamil Nadu coastline, was held in Auroville near Puducherry, where senior government officials from Tamil Nadu and Puducherry as well as hydrologists from it Chennai, NIOT, CWPRS discussed strategies to save the coastline. "It was unanimously agreed that soft solutions such as beach nourishment using a sand bypass system should be used to control erosion," says Probir Banerjee, a civil engineer and coordinator of Pondicherry Citizens Action Network (PONDYCAN).

Kudale of CWPRS also believes that groynes are a hard solution and must be built if there are no alternatives. He believes that bypass systems have worked very successfully at Visakhapatnam's port where there is a similar problem. At the November 2007 consultation, the Puducherry government officials assured that the sand bypass system would be reactivated. But a few days after the meet, rocks began to be dumped at the Kuruchikuppam area towards the north of Puducherry town-for erecting groynes. This was done without applying for coastal regulation zone (CRZ) clearance.

In January 2008, PONDYCAN along with another NGO, Coastal Action Network, filed a public interest litigation in the Chennai high court, seeking a stop on the construction work. A month later, the court directed that the public works department should get environmental clearances for the project. The department applied for CRZ clearance in February 2008.

According to a Union environment ministry official, the Centre had asked the Puducherry government to stop work on the groynes because it had not applied for CRZ clearance. "A notice was sent to the state public works department asking it to stop all work on the groynes, he said."

Meanwhile in January this year, the Tamil Nadu government initiated an enquiry on erosion in Kottakuppam block in Villupuram district. The report of the enquiry noted. "All villages in Kottakuppam block and other areas of Vannur Taluk of Villupuram north of Puducherry, are at the risk of sea erosion because sea walls/groynes had blocked the natural transport of sand up and down the coast." It further added that if construction proceeds further in Puducherry, it would "aggravate the erosion on Tamil Nadu coast especially in the Villupuram district". PONDYCAN also petitioned the environment ministry against the Puducherry government's groyen building spree. In January, Meena Gupta, then secretary at the ministry, wrote a letter to Puducherry's chief secretary, Rashid Behary, asking him to initiate a dialogue with his counterpart in Tamil Nadu. "It has been brought to our notice that the recent construction of groynes has only shifted the problem north of Puducherryt I would appreciate it if you could ask the concerned authorities in Puducherry to discuss the matter with their counterparts in Tamil Nadu, so that our beaches can be saved," Gupta wrote. On May 22, 2008 the issue of CRZ clearance came up before the ministry's additional expert committee of new construction. The ministry sought details of littoral drift, erosion and alternative measures for shore protection. Gupta had also instructed that the expert committee must consult the groups opposing the groynes before recommending clearance. "The secretary had clearly noted that PONDYCAN be consulted when members of the expert committee visit the site. But that wasn't done" says Aurofilio Schiavina, a hydrologist based in Puducherry.

In fact, according to an environment ministry official, the committee had almost decided to give go-ahead to the groynes in its July 31 meeting. One of the members then pointed out that objections against the structures had not been weighed and they had to be studied before considering the application for clearance.

(Source: CSE/Down To Earth Feature Service)

Containing Delhi's air pollution

New Delhi, April 25, 2008: Delhi might soon lose its war against growing traffic and increasing pollution, without an effective and massive public transport system. Delhi needs big answers for its big problem and tough measures like the Bus Rapid Transit (BRT) system is one such solution in the future roadmap. This thumbs-up for the BRT came here today from Bhure Lal, chairperson of the Environment Pollution (Prevention and Control) Authority (EPCA), as well as Sunita Narain, director, Centre for Science and Environment (CSE).

"Once seen as one of the most polluted cities in the world, Delhi did succeed in arresting its air pollution through big-ticket solutions like the introduction of CNG. Our research tells us that Delhi could negate the gains made because of the phenomenal increase in vehicle numbers in the city. The answer will be to invest heavily in public transport, increase the bus fleet and restructure the bus service. But all this is not enough unless we can provide space for the bus to move and it is for this reason that the BRT is one solution," said Bhure Lal.

"The fact also is that buses have not been replaced in India by the car or the two-wheeler as is the situation in other parts of the world. Instead, buses have only been marginalized. Even today, buses in this city, which has an old and disorganized public transport system, move between 50-60 per cent of its people," added Sunita Narain. "This is why we need a system that can efficiently move the bulk of the city passengers and even provide options for the rest to move towards bus transport and BRT provides us this option. Out of the roughly 16 million passenger trips in the city, buses cater to roughly 9 million passenger trips.

As part of its effort to control pollution, EPCA is working on a four-pronged agenda.

Agenda: Increase buses

The first task is to increase the number of buses. EPCA has in its reports has noted that Delhi is short of the 10,000 bus target for buses set by the Supreme Court. The city has since ordered 500 new buses and placed tenders for another 4500 buses. EPCA is monitoring progress Agenda: Revamp bus service EPCA has also noted that the Delhi bus service needs re-structuring so that it is efficient and convenient. Delhi government has submitted plan for revamp of bus service-clusters of bus routes have been made and tender opened. EPCA monitoring progress Agenda: Increase public transport and connectivity between NCR towns It is surprising to note that there is no connectivity between Delhi and neighbouring cities. For instance, there is no bus service between Delhi-Gurgaon. Now a memorandum is being signed between states for public transport in NCR, only on CNG.

Agenda: Provide buses space to move within cramped road space In late 2005, Delhi government has proposed the BRT to the Hon'ble Supreme Court has one option to increase bus transport efficiently. The Court accepted its proposal and asked EPCA to monitor progress of the corridors.

"It is important to note that Delhi is running out of road space and options" says Bhure Lal.

Consider:

Delhi already has 21% of its land area under roads

Between 1996 and 2006 road length increased by 20%. Cars increased by 132 per cent

So road space decreased, not increased

In 2001; 8.5 km available per vehicle

In 2007: 6 km available per vehicle

This will decrease further as the city adds about 1,000 vehicles each day on its roads. The only option is to make the transition to public transport.

"The BRT corridor will provide space to the over 60 per cent of people in Delhi either travel by bus, or bicycle or walk to work. We know that cars take 75 per cent of the road space, but carry just less than 20 per cent of people. It is time we gave the bus its due space on our roads. Also, an improved bus service will certainly attract more commuters," added Narain.

"There is no doubt that there have been problems in its implementation. But that does not mean that we should give up on this big idea. We will have to learn from this experience and do even better in the remaining corridor. We believe that Delhi, which is faced with the same problems across all its roads, has no other option but to turn towards solutions like the BRT system. Like the transition to CNG, which also went through a lot of problems before we got benefit of its gain, this transition will also take time," said Bhure Lal and Narain.

(To contain Delhi's growing air pollution and congestion, BRT is a step in the right direction-says Bhure Lal of the Environment Pollution (Prevention and Control) Authority (EPCA) and Sunita Narain, director, CSE)