CAMARINES NORTE PROVINCE, Philippines -- A teenage boy places some sand mixed with gold and some mercury onto a large, shallow, wooden plate then kneads the mixture with his hands.
He adds some water, and repeatedly sifts out the unwanted sand and waste, leaving behind a shiny alloy of gold and mercury in the center of the plate. "If you heat this up, you get high-grade gold," the 15-year-old boy, Reynan Broso, explains.
Broso lives in the Philippine province of Camarines Norte, where the beaches consist of a combination of black sand mixed with gold. Renowned as a gold region even before the country was colonized by Spain in the 16th century, the province is now an area where impoverished children carry out a task known as artisanal and small-scale gold mining (ASGM), which makes use of mercury.
"I don't go to school so I get bored, with nothing to do," Broso says. The youngster graduated from elementary school but couldn't afford to proceed to the next level of schooling and has found himself doing ASGM work since the age of 10.
ASGM poses a health risk as workers often touch the toxic mercury with their bare hands and breathe in the steam when the mercury is heated. Broso learned this only recently.
"This is the first time I've heard it's bad for your health," he said when he was told.
Some 100 concrete enclosures can be seen at the edge of the water, each measuring about 1 meter by 1 meter. Underneath them are holes that extend to a depth of 50 meters. These holes were dug to enable workers to collect gold dust and gold ore from deep underground. However, in 2016, the use of these holes was banned by the local government in response to an order from the central government, and they now lie idle. The order came as these holes had been operated without authority's permission.
"The holes supported a large number of families in this area, but now everyone has moved away," says a senior member of one ASGM organization. Broso's father also used to work in the area. Now, with the holes banned, he focuses on catching small fish, which Broso's mother and older brother then sell to support their living costs.
Broso's revenue is precious. Each day, he earns the equivalent of 500 yen (a little over $4) which is used up buying food for the family. His younger sister has a congenital illness that left a hole in her heart, and she needs medicine. "What will happen to our family? I'm extremely worried," Broso says.
The majority of ASGM work in the Philippines is unlicensed. This is because it is expensive to compile the necessary documents when applying to the government for a permit. However, if the authorities crack down on poor families such as Broso's, then this leads to further poverty. With this reality in mind, officials turn a blind eye.
There are other problems emerging, as revealed by a man who employs about 20 people as part of his gold-digging operation in another part of the province: "If we dig a new hole in order to collect gold ore, police officers appear one by one asking for bribes in exchange for not reporting us." The bribes are thus paid, instantly halving workers' incomes.
When Broso -- who is unaware of such corrupt practices -- was asked what he wants to be when he is older, his reply was pure and innocent: "I want to be a police officer. I want to help people who are in trouble." (By Tetsuro Hatakeyama, Science & Environment News Department)
This is part four of a series on mercury poisoning.