Every breath you take
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《英国医生杂志》
New Delhi
Indoor stoves and a boom in diesel cars are contributing to dangerous levels of air pollution in South Asia. Sanjay Kumar reports
Simple neglected public health issues, not exotic ones, dominate the agenda for environmental health in the South Asian region.
"Lack of safe sanitation, water, and hygiene are the biggest cause of infection and the key issues for environmental health in the region," says Gourisankar Ghosh, executive director of the Water Supply and Sanitation Collaborative Council, the Geneva based UN mandated body for water and sanitation goals. The council calls this inadequacy "one of the biggest scandals of the last 50 years."
South Asian countries are among the countries whose hygiene levels are "disastrous," says the council. In India alone, 519 500 children die every year from poor hygiene; the equivalent figures in neighbouring Pakistan and in Afghanistan are 135 000 and 48 000 respectively.
The primary cause of this is unsafe disposal of human excreta: 72% of human excreta in India is disposed of in an unsafe way. The amounts of excreta disposed of in an unsafe way in other countries in the region are 72% in Nepal, 88% in Afghanistan, 52% in Bangladesh, 38% in Pakistan, and 30% in Bhutan. These figures are given by the Water Supply and Sanitation Collaborative Council in a new report called Listening (www.wsscc.org/listening/).
Frequent illnesses, especially diarrhoea, undermine children's growth by taking away their appetite, inhibiting the absorption of nutrients, burning up calories in fever, and fighting infection, says the council. As a consequence, the percentage of children not growing normally is as high as 47% in India, 38% in Pakistan, 47% in Bangladesh, 47% in Nepal, 48% in Afghanistan, and 33% in Sri Lanka, says the report.
"There is very little focus on environmental health in this region as a whole," laments Mr Ghosh.
More than nine tenths of rural households and a fifth of urban households in India use wood, dung, or crop residues as a fuel in open fires or simple stoves, mostly indoors. This is rarely done with adequate ventilation—leading to some of the highest ever recorded levels of air pollution, says the World Bank, a story finding eloquent echo in the rest of the region.
The World Health Organization estimates that toxic indoor air pollution is causing nearly half a million premature deaths and some 500 million cases of illness, with about 16 million years of healthy life lost among women and children in India alone annually.
"Exposure to indoor pollution can also lead to a higher risk for tuberculosis, especially among the poor," says Jai Prakash Narain, coordinator for HIV/AIDS and tuberculosis for WHO in Delhi. "It is common sense that indoor pollution damages the respiratory system, thereby leading to higher susceptibility to tuberculosis," he adds. India, Bangladesh, Pakistan, and Afghanistan are four of the 22 countries with the highest burden of tuberculosis.
Pakistan witnessed its biggest environmental disaster last year when an oil tanker, the Tasman Spirit, broke in two in Karachi harbour
Credit: AAMIR QURESHI/AFP/GETTY
Outdoor air pollution in Karachi and Lahore has been estimated to be 20 times higher than the limits set by WHO. Cities in South Asia remain among the most polluted in the world, with the number of vehicles increasing uncontrollably.
Vehicular air pollution has been the focal point in recent years of public health campaigns and legal battles waged by the Centre for Science and Environment, Delhi. As a result of a Supreme Court order in 2002, the government forced the highly polluting diesel buses and three wheeled vehicles to switch to compressed natural gas by 31 January 2003. In Pakistan too, more than 265 000 vehicles have switched to compressed natural gas and more than 300 such gas stations have been set up.
But under the vehicle and fuel policy pursued by the Indian government, there has been a 106% increase in diesel cars since 1998-9, compared with a 12% increase in petrol cars in the same period, the centre says.
Diesel consumption has in fact increased by 39% since 1995 despite a sizeable conversion of diesel buses to compressed natural gas, as diesel is 35% cheaper.
"As a result of this completely flawed policy, paediatric asthma cases are on the rise again in Delhi after stabilising, and if this "dieselisation" mania goes unchecked, it will wipe out all the gains of the compressed natural gas switchover," says Pranay Lal, coordinator for health and environment at the Centre for Science and Environment.
Vehicles in Pakistan emitted some 550 tonnes of lead annually before lead-free petrol was introduced. Leaded petrol is now being phased out, but studies previously conducted in Karachi, Peshawar, Lahore, Dhaka, and Delhi all indicated unsafe high levels of lead in the air, with predicted adverse effects on brain development and IQ levels of children.
Pakistan, India, and Bangladesh have now all recently switched to lead-free petrol (after different phase-ins in the three countries), thereby reducing lead levels substantially in the atmosphere. But other sources of lead, such as batteries, pipelines, lead based paints, and ceramics, remain a health threat.
Arsenic in groundwater used for drinking in Bangladesh and West Bengal remains the world's biggest mass poisoning episode. Surveys estimate that in these countries more than 35 million people are drinking unsafe, arsenic laden water, and at least 150 million people are at risk ( BMJ 2003;326: 466).
The disaster is still unfolding. New sites have been discovered in Jharkhand and Bihar states, India. In Nepal, investigations by the Nepalese Red Cross and the Environment and Public Health Organization have found that 37% of tested tube wells in the Terai region have arsenic laden water beyond safe limits. Forty seven per cent of Nepal's population lives in this region and 3.19 million people may be affected, says the organisation.
Oil spills, on the other hand, are posing threats to the regions with huge coastlines. Last year, Pakistan witnessed its biggest environmental disaster when a Maltese oil tanker, the Tasman Spirit, broke in two in Karachi harbour, releasing more than 25 000 tonnes of crude oil.
The spill posed serious threats to the entire ecosystem and the nearby residential areas, with pungent fumes affecting the eyes and throats of thousands of people. Although short term effects included headaches, nausea, and throat infections, long term effects are not known.
Another newly emerging threat to environmental health is electronic waste (obsolete computers and television sets) being exported to countries such as India, China, and Pakistan from the United States for waste recycling. These units, estimated to total more than 10 million in 2002, come under the guise of "used working computers" with toxic parts containing lead, beryllium, mercury, cadmium, and brominated flame retardants, says the Delhi based non-governmental organisation Toxics Link.(Sanjay Kumar)
Indoor stoves and a boom in diesel cars are contributing to dangerous levels of air pollution in South Asia. Sanjay Kumar reports
Simple neglected public health issues, not exotic ones, dominate the agenda for environmental health in the South Asian region.
"Lack of safe sanitation, water, and hygiene are the biggest cause of infection and the key issues for environmental health in the region," says Gourisankar Ghosh, executive director of the Water Supply and Sanitation Collaborative Council, the Geneva based UN mandated body for water and sanitation goals. The council calls this inadequacy "one of the biggest scandals of the last 50 years."
South Asian countries are among the countries whose hygiene levels are "disastrous," says the council. In India alone, 519 500 children die every year from poor hygiene; the equivalent figures in neighbouring Pakistan and in Afghanistan are 135 000 and 48 000 respectively.
The primary cause of this is unsafe disposal of human excreta: 72% of human excreta in India is disposed of in an unsafe way. The amounts of excreta disposed of in an unsafe way in other countries in the region are 72% in Nepal, 88% in Afghanistan, 52% in Bangladesh, 38% in Pakistan, and 30% in Bhutan. These figures are given by the Water Supply and Sanitation Collaborative Council in a new report called Listening (www.wsscc.org/listening/).
Frequent illnesses, especially diarrhoea, undermine children's growth by taking away their appetite, inhibiting the absorption of nutrients, burning up calories in fever, and fighting infection, says the council. As a consequence, the percentage of children not growing normally is as high as 47% in India, 38% in Pakistan, 47% in Bangladesh, 47% in Nepal, 48% in Afghanistan, and 33% in Sri Lanka, says the report.
"There is very little focus on environmental health in this region as a whole," laments Mr Ghosh.
More than nine tenths of rural households and a fifth of urban households in India use wood, dung, or crop residues as a fuel in open fires or simple stoves, mostly indoors. This is rarely done with adequate ventilation—leading to some of the highest ever recorded levels of air pollution, says the World Bank, a story finding eloquent echo in the rest of the region.
The World Health Organization estimates that toxic indoor air pollution is causing nearly half a million premature deaths and some 500 million cases of illness, with about 16 million years of healthy life lost among women and children in India alone annually.
"Exposure to indoor pollution can also lead to a higher risk for tuberculosis, especially among the poor," says Jai Prakash Narain, coordinator for HIV/AIDS and tuberculosis for WHO in Delhi. "It is common sense that indoor pollution damages the respiratory system, thereby leading to higher susceptibility to tuberculosis," he adds. India, Bangladesh, Pakistan, and Afghanistan are four of the 22 countries with the highest burden of tuberculosis.
Pakistan witnessed its biggest environmental disaster last year when an oil tanker, the Tasman Spirit, broke in two in Karachi harbour
Credit: AAMIR QURESHI/AFP/GETTY
Outdoor air pollution in Karachi and Lahore has been estimated to be 20 times higher than the limits set by WHO. Cities in South Asia remain among the most polluted in the world, with the number of vehicles increasing uncontrollably.
Vehicular air pollution has been the focal point in recent years of public health campaigns and legal battles waged by the Centre for Science and Environment, Delhi. As a result of a Supreme Court order in 2002, the government forced the highly polluting diesel buses and three wheeled vehicles to switch to compressed natural gas by 31 January 2003. In Pakistan too, more than 265 000 vehicles have switched to compressed natural gas and more than 300 such gas stations have been set up.
But under the vehicle and fuel policy pursued by the Indian government, there has been a 106% increase in diesel cars since 1998-9, compared with a 12% increase in petrol cars in the same period, the centre says.
Diesel consumption has in fact increased by 39% since 1995 despite a sizeable conversion of diesel buses to compressed natural gas, as diesel is 35% cheaper.
"As a result of this completely flawed policy, paediatric asthma cases are on the rise again in Delhi after stabilising, and if this "dieselisation" mania goes unchecked, it will wipe out all the gains of the compressed natural gas switchover," says Pranay Lal, coordinator for health and environment at the Centre for Science and Environment.
Vehicles in Pakistan emitted some 550 tonnes of lead annually before lead-free petrol was introduced. Leaded petrol is now being phased out, but studies previously conducted in Karachi, Peshawar, Lahore, Dhaka, and Delhi all indicated unsafe high levels of lead in the air, with predicted adverse effects on brain development and IQ levels of children.
Pakistan, India, and Bangladesh have now all recently switched to lead-free petrol (after different phase-ins in the three countries), thereby reducing lead levels substantially in the atmosphere. But other sources of lead, such as batteries, pipelines, lead based paints, and ceramics, remain a health threat.
Arsenic in groundwater used for drinking in Bangladesh and West Bengal remains the world's biggest mass poisoning episode. Surveys estimate that in these countries more than 35 million people are drinking unsafe, arsenic laden water, and at least 150 million people are at risk ( BMJ 2003;326: 466).
The disaster is still unfolding. New sites have been discovered in Jharkhand and Bihar states, India. In Nepal, investigations by the Nepalese Red Cross and the Environment and Public Health Organization have found that 37% of tested tube wells in the Terai region have arsenic laden water beyond safe limits. Forty seven per cent of Nepal's population lives in this region and 3.19 million people may be affected, says the organisation.
Oil spills, on the other hand, are posing threats to the regions with huge coastlines. Last year, Pakistan witnessed its biggest environmental disaster when a Maltese oil tanker, the Tasman Spirit, broke in two in Karachi harbour, releasing more than 25 000 tonnes of crude oil.
The spill posed serious threats to the entire ecosystem and the nearby residential areas, with pungent fumes affecting the eyes and throats of thousands of people. Although short term effects included headaches, nausea, and throat infections, long term effects are not known.
Another newly emerging threat to environmental health is electronic waste (obsolete computers and television sets) being exported to countries such as India, China, and Pakistan from the United States for waste recycling. These units, estimated to total more than 10 million in 2002, come under the guise of "used working computers" with toxic parts containing lead, beryllium, mercury, cadmium, and brominated flame retardants, says the Delhi based non-governmental organisation Toxics Link.(Sanjay Kumar)