JIM LEHRER: Finally tonight, arsenic poisoning in the South Asian nation of Bangladesh. Fred de Sam Lazaro of KTCA-Minneapolis-St. Paul has our report.
FRED DE SAM LAZARO: The first thing a visitor sees in the village of Hatkopa is its water pump, for years the source of drinking water for most residents. It's the symbol of one of the most successful public health campaigns in the developing world. It's also a symbol of one of the biggest dangers to public health in Bangladesh. Water has long been a mixed blessing in Bangladesh. Until the 1970's, rivers and ponds like these served as the only water source for bathing, laundering, and drinking. That compromised hygiene. The exposure to wastes and infections caused tens of thousands of deaths in children each year, so the charity UNICEF thought it had a way to stop the death toll. It began sinking thousands of tube wells, tapping the abundant groundwater in the soggy nation that would be safe from bacteria and pollutants that are found in surface waters. But starting in the late 1980's, doctors began seeing patients with unusual symptoms, like skin rashes and warts, conditions that prompted an Indian doctor to test the water supply. It turned out the water from many of these tube wells contained dangerous levels of arsenic, a deadly element that occurs naturally through much of this region.
FRED DE SAM LAZARO: This is just five minutes old, and it's already quite -
DR. IFTIKHAR HUSSAIN: Yes, just five minutes after.
FRED DE SAM LAZARO: Quite yellow.
DR. IFTIHKHAR HUSSAIN: Yeah.
FRED DE SAM LAZARO: Dr. Iftikhar Hussain, with the country's health ministry, carries a small test kit to check on which wells contain the deadly poison. Those that are safe are painted green; those that are contaminated are painted red.
DR. IFTIKHAR HUSSAIN: So this is already quite higher than the national standard.
FRED DE SAM LAZARO: And the national standard is somewhere between these two.
DR. IFTIKHAR HUSSAIN: Between these two.
FRED DE SAM LAZARO: And this is way past there, so at least -
DR. IFTIKHAR HUSSAIN: Yes.
FRED DE SAM LAZARO: More than 100% worse than the allowable standard?
DR. IFTIKHAR HUSSAIN: Yes.
FRED DE SAM LAZARO: Hatkopa is one of 200 villages whose tube wells were recently tested under a U.N. program. Two-thirds of them of them were found to have unacceptably high levels of arsenic contamination. A staggering 15 million to 30 million Bangladeshis may be at risk. That would make this by far the worst case of mass poisoning in history. Also, the U.N. development program's Shireen Kamal Sayeed says it's slow and insidious.
SHIREEN KAMAL SAYEED: It's a very silent epidemic. It's a long-term effect, and it takes ten, 15 years for arsenic poison to accumulate in the human body.
FRED DE SAM LAZARO: So far, the vast majority of people affected are in the early stages of arsenic poisoning, showing signs of skin rashes and lesions.
DR. IFTIKHAR HUSSAIN: Now it has gone into the second stage. It has one some nodular growth. And this is called hyperkeratosis.
FRED DE SAM LAZARO: Hyperkeratosis?
DR. IFTIKHAR HUSSAIN: Hyperkeratosis.
FRED DE SAM LAZARO: Symptoms like those of Mohammad Abdul Barek's worsen if they're not checked. They can lead to warts, gangrene, and, in many cases, internal organ damage and cancers.
FRED DE SAM LAZARO: Any other symptoms?
FRED DE SAM LAZARO: But Barek's condition and that of his son Kokan actually have improved in recent months, after water from their contaminated well was fitted with an elaborate filtering system being tested by its U.S manufacturer. It works, but at $4,000 per unit is impractical in Bangladesh, where the average annual per capita income is about 1/20 of that figure.
FRED DE SAM LAZARO: The Barek family recently installed a new well, deeper and about 20 yards from the old one. Dr. Hussain's field test was not fully conclusive, so the sample was taken to the lab for a more precise measurement.
SPOKESPERSON: As the problem of arsenic poisoning by groundwater is a recent and unfamiliar phenomenon, many health workers and doctors may not know all the symptoms.
FRED DE SAM LAZARO: This video, produced for the British charity Oxfam and intended to train health workers, shows the damage wrought in subsequent stages of the illness.
SPOKESPERSON: When the situation deteriorates and becomes serious, treatment becomes difficult, and life is at severe risk.
FRED DE SAM LAZARO: The video also tries to educate doctors about the social as well as physical consequences. Women complained of being thrown out of their home by their husbands or becoming social outcasts after developing visible symptoms. What's especially frustrating for doctors is arsenic's varied impact from person to person, even within the same family. For example, Majid Khan shows only mild skin spots, but his father Ansar Ali Khan's body is covered with lesions.
DR. IFTIKHAR HUSSAIN: The very prominent visible sign of leukomelanosis and melanosis and alternate white and black colors. The second stage in the hand; the hardening is done. There is the nodules in the hands.
FRED DE SAM LAZARO: As he did in previous stops, Dr. Hussain tested water from a new well sunk by the khan family, one deeper than their old, contaminated one, but only a few feet away.
DR. IFTIKHAR HUSSAIN: So I think that's okay. That's fine.
FRED DE SAM LAZARO: Even though their new well tested clean, the Khans aren't guaranteed clean water forever. To all the uncertainties in this epidemic, add geology. The arsenic level in wells does not remain constant.
SHIREEN KAMAL SAYEED: But that doesn't mean that the other well will not start giving off arsenic-contaminated water in three months' time, six months', or a year's time, so each and every well has to be tested.
FRED DE SAM LAZARO: And tested again and again. It will take years to just test for the first time the four million wells nationwide, a daunting logistical and financial undertaking. In the meanwhile, public health officials fear many of the poor and illiterate, lacking a sense of urgency or other options for drinking water, or the ability to test all wells, may continue to drink from contaminated ones.
DR. IFTIKHAR HUSSAIN: The results we are getting about the contamination and informing the people is not enough, to them, to stop people from the contaminated water, until they get a good alternate source of water, because still, they don't want to take the water from the pond which looks dirty, and, you know, bacteriologically is not safe.
FRED DE SAM LAZARO: In the end, experts say it will likely be widespread disease and death that will be the catalyst for changed behavior.
SHIREEN KAMAL SAYEED: If people are made aware of the dangers of arsenic, and they obviously -- those who are infected right now and can see the symptoms in their hands, and they're suffering. They can't work; they've been thrown out of their houses; they've been sent out by their parents, not accepted by their husbands -- these are the people who will take heed, and then their families. So it will start coming into the community.
FRED DE SAM LAZARO: Sayeed predicts an explosion of serious arsenic exposure cases in the next five to 15 years. Still, ironically, public health experts say tube wells have prevented more deaths from water-borne infections than they will claim through arsenic poisoning.
