Ban Mae Toen is a small rural village in the Thai province of Lampang, 300 miles away from Bangkok. Unfortunately for the villagers, it is close to a fluoride mine. Though the mine closed 40 years ago, the area has become home a polluted artificial lake that overflows during the rainy season. Given the lack of other water supplies, years of people drinking from the lake has made Ban Mae Toen a very sick village. The symptoms still can be seen across three generations. The children may experience brain damage, deaf-mutism, or slow brain development; some older people, particularly women, have an enlarged thyroid gland on their necks, as did their parents before them.

Da is 64 years old. When she was 34, she drank water from the lake. As a result, the thyroid gland in her throat is massively enlarged. It’s known as a goiter. She says it is not painful, though it looks awful.

“I have thyroid problems since some time ago, and I have become accustomed to it. I can work at home and it doesn’t hurt. I can go everywhere around the village,” Da says.

When her lump appeared, Da didn’t give it too much thought. She didn’t bother to go to the doctor because she already knew what was going on. When she was younger, she had seen a similar swelling on her mother’s neck and the necks of other older villagers who had also drunk from the lake.

“My mother had the same lump as mine but smaller,” Da says. “For the last 20 years the lump hasn’t grown. The doctor told me that they can remove it, but I won’t. I am weak and I could bleed to death.” Da currently works as a housekeeper and has three grown children who do not have health problems. Like others who have been poisoned by the lake, she does not receive any government assistance.

“The problem we have is that in Ban Mae Toen, the groundwater is used for eating and cooking, and this is contaminated by with fluoride,” says Dr. Chatpat Kongpun, who works at the Ministry of Public Health Thailand. “Some of the younger generation still suffer health problems, but their problems are not as severe as those of the older people,” he says.

In Thailand and other Southeast Asian countries, the lack of drinking water is a serious problem because it usually only rains during the monsoon season between May and October. That’s why people in Ban Mae Toen drink from the lake.

At the time of a report by the Australian University of Tasmania in 2007, the village had 1,092 inhabitants, 11.2 percent of whom had lumps in their throats like Da. Much of the rest of the population was affected by other conditions. One in three men and two out of three women over 45 years old had some degree of limb deformity. Twelve were unable to walk, 21 had walking difficulties, and 65 percent had stained teeth.

The report pointed to iodine deficiency as the cause of the health problems, saying that ingesting water contaminated with fluoride hinders the absorption of iodine, which is necessary for the human body to function properly—especially the brain and the thyroid gland. When the thyroid does not have enough iodine to perform, it has to work harder, and this causes it to swell, making a goiter.

Iodine is especially vital for the development of the brain and nervous system of babies during the first 12 weeks of pregnancy. “The fetuses of pregnant women who have drunk contaminated water may experience brain damage, deaf-mutism, and mental disability,” says Pornithida Padthong, who was head of communications at UNICEF Thailand until 2013 and worked in the village of Ban Mae Toen.

To help solve the problems caused by fluoride in the village, the Rotary Club of D’Entracasteaux of Tasmania, in Australia, which also funded the report, introduced a water tank supply in 2003 and provided the villagers with receptacles to store the rainwater.

“The main water tank of Ban Mae Toen comes from a borehole three kilometers [two miles] above the village, and has been piped to houses since 2003”, says Neil McGlashan, who worked on the report. The foundation also gave sacks of iodized salt to the villagers.

Officially, nobody drinks from the lake anymore, but according to a report by the organization from 2007, the supply may not be enough to see people through the dry season. “About 50 percent of pregnant women [still] suffered from iodine deficiency when I worked in the village last year,” explains Pornithida Padthong, suggesting that people in Ban Mae Toen may still be drinking poison to this day.

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