- "Water supplies are falling while the demand is dramatically growing at an unsustainable rate [, and] over the next 20 years, the average supply of water worldwide per person is expected to drop by a third. Over 1.5 billion people lack ready access to drinking water and, if current consumption patterns continue, at least 3.5 billion people — nearly half the world’s projected population — will live in water-stressed river basins in just 20 years.”( Water Facts 1).
- "Asian rivers are the most polluted in the world, with three times as many bacteria from human waste as the global average. These rivers have 20 times more lead than those of industrialized countries"( Water Facts 1).
- "Water is becoming scarce due to higher pollution levels and habitat degradation. Contamination denies as many as 3.3 billion people access to clean water supplies. In developing countries, an estimated 90% of wastewater is discharged directly into rivers and streams without treatment. Each year there are about 250 million cases of water-related diseases, with roughly 5 to 10 million deaths"(Water Facts 1).
- “One liter of wastewater pollutes about eight liters of freshwater. An estimated 12,000 km3 of polluted water worldwide, which is more than the total amount contained in the world’s ten largest river basins at any given moment. Therefore, if pollution keeps pace with population growth, the world will effectively lose 18,000 km3 of freshwater by 2050 – almost nine times the total amount countries currently use each year for irrigation, which is by far the largest consumer of the resource” (Water Facts 1).
What is Water Pollution?
The National Environmental Agency, a branch of the Ministry of Science, Technology, and Environment, is responsible for environmental issues in Vietnam.
At the provincial level, the Departments of Science, Technology, and the Environment bear responsibility. Non-governmental organizations, particularly the Institute of Ecological Economics, also play a role. Urbanization, planning, industrialization, and intensive farming are having a negative impact on Vietnam’s environment. These factors have led to air pollution, water pollution, and noise pollution, particularly in urban and industrial centers like Ho Chi Minh City and Hanoi. The most serious problem is waste treatment. Land use pressures have led to significant environmental problems, including severe deforestation, soil erosion, sedimentation of rivers, flooding in the deltas, declining fish yields, and pollution of the coastal and marine environment. The use of Agent Orange by the U.S. military in the Second Indochina War, or Vietnam War, (1954– 75) has had a lingering effect on Vietnam in the form of persistent environmental contamination that has increased the incidence of various diseases and birth defects.
Agent Orange is the code name for one of the herbicides and defoliants used by the U.S. military as part of its herbicidal warfare program, Operation Ranch Hand, during the Vietnam War from 1961 to 1971.
A 50:50 mixture of 2,4,5-T and 2,4-D, it was manufactured for the U.S. Department of Defense primarily by Monsanto Corporation and Dow Chemical. The herbicides used to produce Agent Orange were later discovered to be contaminated with TCDD, an extremely toxic dioxin compound. It was given its name from the color of the orange-striped 55 US gallons (210 L) barrels in which it was shipped, and was by far the most widely used of the so-called "Rainbow Herbicides".
During the Vietnam war, between 1962 and 1971, the United States military sprayed 20,000,000 US gallons (80,000,000 L) of chemical herbicides and defoliants in Vietnam, eastern Laos and parts of Cambodia, as part of Operation Ranch Hand. The program's goal was to defoliate forested and rural land, depriving guerrillas of cover; another goal was to induce forced draft urbanization, destroying the ability of peasants to support themselves in the countryside, and forcing them to flee to the U.S. dominated cities, thus depriving the guerrillas of their rural support base and food supply.
Air Force records show that at least 6,542 spraying missions took place over the course of Operation Ranch Hand. By 1971, 12 percent of the total area of South Vietnam had been sprayed with defoliating chemicals, which were often applied at rates that were 13 times as high as the legal USDA limit.In South Vietnam alone, an estimated 10 million hectares of agricultural land were ultimately destroyed. In some areas TCDD concentrations in soil and water were hundreds of times greater than the levels considered "safe" by the U.S. Environmental Protection Agency. Overall, more than 20% of South Vietnam's forests were sprayed at least once over a nine year period.
The US began to target food crops in October 1962, primarily using Agent Blue. In 1965, 42 percent of all herbicide spraying was dedicated to food crops. Rural-to-urban migration rates dramatically increased in South Vietnam, as peasants escaped the destruction and famine in the countryside by fleeing to the U.S.-dominated cities. The urban population in South Vietnam more than tripled: from 2.8 million people in 1958, to 8 million by 1971. The rapid flow of people led to a fast-paced and uncontrolled urbanization; an estimated 1.5 million people were living in Saigon slums, while many South Vietnamese elites and U.S. personnel lived in luxury.
According to Vietnamese Ministry of Foreign Affairs, 4.8 million Vietnamese people were exposed to Agent Orange, resulting in 400,000 people being killed or maimed, and 500,000 children born with birth defects.
Agent Orange by the U.S. war has caused environmental pollution, especially water environments in Vietnam and their impact on the people of Vietnam:
At least 500,000 people were affected by waterborne diseases during 1995-2000 in the union territory of Pondicherry due to the lack of coordination among the government agencies. According to a report of the Comptroller and Auditor General of India, the quality of ground and surface water in all four regions of Pondicherry is not in accordance with the prescribed standards. The report also states that the union territory's pollution control committee has shown a lax attitude towards carrying out pollution tests. The water testing was done only when complaints were received. According to the report, the waterbodies of Pondicherry are being polluted as industries are indiscriminately dumping toxic effluents into them.
The parasites in these two papers were of two categories, the known pathogens Cryptosporidium parvum ("Crypto") and Giardia lamblia ("Giardia"); and the more recently discovered microsporidia, Enterocytozoon bieneusi and Encephalitozoon intestinalis. The latter two have been known to cause human disease, especially (but not exclusively) in immunocompromised individuals, but they are hard to test for and identify so we know little about their epidemiology, including where those infected encountered them. Crypto and Giardia, on the other hand, have caused numerous waterborne disease outbreaks (including the largest in US history in Milwaukee in 1993, from Crypto) and both are highly resistant to chlorination. Their cysts can remain viable in a hostile environment as long as a year.
These papers are taken up with technical details relating how the samples were taken, handled and analyzed. These are important because much still needs to be worked out and variations in how these things are done is necessary to compare one study with another. But the bottom line is relatively simple: For either class of parasite there was a significant relationship between levels and the humber of bathers. Samples were taken on busy weekends and compared with lightly populated weekdays. Almost half the samples had microsporidia and levels of Crypto ranged from zero to 42 cysts/liter and Giardia from zero to 33 cysts/liter. How much of this stuff does it take to make you sick. For the microsporidia we aren't sure. We'll need human volunteer feeding studies to nail this down. For Crypto and Giardia it depends on the strain. In some cases the answer is less than 10 cysts.
What is the source? Again, we still aren't sure. These studies show clearly that the turbidity or cloudiness of the water is directly related to bather density. So stirring up sediments is happening and this could be the source. But bathers are also sources. It has been estimated that anal fecal residue shed to water amounts to 0.14 g and may be as high as 10 grams (this is from a paper by Chuck Gerba, Quantitative Microbiology 2:55-68, 2000). Despite this estimates of Crypto and Giardia risk from swimming in lakes is estimated to be pretty low (less than one in ten thousand).
But one of the things these studies show is that there are pathogens in recreational waters even when they meet standards deemed acceptable by state and federal bacterial standards. These beaches were legally open to the public. Thus the bacterial indicator standards are of doubtful protection. It further underlines the commonsense notion that public drinking water sources should be separated from recreational bathing locales.
And there are other possible interventions. Limit the number of bathers, prohibit children in diapers and advise anyone symptomatic to stay away