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Worries of Minamata disease-like crisis amid mercury-based gold refining boom in Cambodia

Ron Naroath helps out with his family's gold processing business in Romtom commune, Preah Vihear province, Cambodia. (Mainichi)

PREAH VIHEAR PROVINCE, Cambodia -- Mercury pours out over 12-year-old Ron Naroath's hands and down his fingers as he wrings out a cloth.

"I've never heard that it's bad for your health," he says.

Every day after school, Naroath heads to an open-air workshop in the rural commune of Romtom to help his 41-year-old father Kien Saron with his business: using mercury to purify gold, or "artisanal and small-scale gold mining" (ASGM).

In the process used by Saron, machine-ground gold ore is poured over a tray that has been painted with mercury. The gold clings to the mercury, after which the mixture is put in a cloth. When the cloth is wrung out, the pressure squeezes out the mercury, leaving behind only the gold. The precious metal in the cloth is treated with another chemical and then heated, resulting in nearly pure gold which Saron sells to nearby shops.

Father and son do the work with their bare hands, but Naroath insists that he has "never felt sick."

Naroath's family moved to Romtom some six years ago from Kampong Cham province, about 150 kilometers to the south. Before moving, Saron worked at a rubber tree plantation earning about 10,000 yen per month -- far too little to feed his family. Hoping for a quick income boost, Saron set his sights on the gold business. Soon, he had taken his family north to Romtom, famed in Cambodia for its plentiful gold deposits.

At first, Saron tried to mine the gold ore himself, but brought in far less than he had anticipated. Now, he loans an ore grinder to other miners, and processes any extra ore dust into gold.

Romtom was once controlled by anti-government Khmer Rouge guerrillas, but many people began moving into the area in around 2000 after Pol Pot's once fearsome force effectively disintegrated. Now, Romtom has around 5,500 residents, about 10 percent of who work in small-scale gold mining and refining. One needs government permission to get into the business. However, applying for permission cost money, and there are many unlicensed operators, Naroath's family among them.

The mercury-based refining technique the family uses arrived in Cambodia about two years ago with Vietnamese newcomers, whose number has sharply increased in Cambodia over the past two years.

"We buy mercury from a Vietnamese person. We get a lot of gold when we use mercury," Naroath told the Mainichi Shimbun. His father said, "I only learned that mercury is bad for your health a little while ago. But I can't extract the gold well if I don't use mercury, and we wouldn't make enough money to support the family. I'm worried (about the mercury), but I have no choice."

Chap Thala, head of the mercury issue for Preah Vihear province's environmental section, has come to observe Naroath and others like him working with the poisonous element.

"If people in the ASGM workshops absorb mercury directly or people are ingesting mercury in fish contaminated by runoff into rivers and rice fields, the problem presents a very serious health risk," Thala told the Mainichi. "We have to teach people about mercury poisoning if we want to prevent something like Japan's Minamata disease from happening here."

Meanwhile, in Battambang province on the Thai border, the local government gave instructions on safer gold processing at ASGM workshops about three years ago. Now, workers wear masks and gloves, and have collection pools to prevent the mercury-tainted wastewater from escaping into the environment.

According to 36-year-old Lay Sreypov, deputy head of one ASGM workshop, "a few years ago the mercury was just allowed to leak out, and nearby cattle that drank the tainted water died. Implementing countermeasures after human health problems appeared would be too late." (By Tetsuro Hatakeyama, Science and Environment Department)


This is part three of a series on mercury poisoning.

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