Workers in Zimbabwe exposed to toxic mercury in illegal gold mining operations

William Brangham:

The chemical mercury is considered so dangerous to humans and the environment that more than 100 countries have agreed to try and end its use.

But, across the world, millions of miners are still exposed to the toxic metal, including in Zimbabwe, where a majority of miners depend on it to help them extract a much more precious metal.

Nick Schifrin reports, in collaboration with the Global Press Journal.

Nick Schifrin:

In Mutare in Eastern Zimbabwe, it's a gold rush. Unregistered illegal miners are busy at work scouring the muck with only the tools God gave them, hinging their hopes on a silvery chemical. They use liquid mercury.

They have no idea it's toxic; 42-year-old Admire Munjoma has been mining for six years.

Admire Munjoma, Miner (through translator):

When it comes to mercury, we are not aware of any dangers. The only thing I know is that mercury locates gold.

Nick Schifrin:

Cepas Kamusond is 24.

Cepas Kamusond, Miner (through translator):

When it comes to health issues, we really don't have a clue. Sometimes, we put food in the same dishes that we put mercury in.

Linda Mujuru, Global Press Journal:

When I spoke to the miners on the ground, they indicated that they had no idea that the mercury that they were touching every day, the mercury that they were breathing every day posed some dangers to their health.

Nick Schifrin:

Linda Mujuru is an investigative journalist with the Global Press Journal. She's reported on mercury use in gold mining for more than five years.

She says half-a-million unregistered miners hunt for gold in Zimbabwe, and most use mercury. With children swimming in the background, they sift through river rocks, hoping to pick up gold. They swirl the rocks around and add mercury, which clings to gold like metal to a magnet.

The fire releases toxic vapors, but it also helps separate the mercury from the gold, the miners' ultimate prize, despite the price to their health.

What do they tell you when you tell them that it's dangerous?

Linda Mujuru:

Some of them were grateful for this information. But they indicated that, since now they knew of the dangers that was posed by mercury in the mining processes, they were not going to stop mining. The reason why is that they have no alternatives in terms of survival.

Nick Schifrin:

Like 37-year-old Clemence Tembo. He ended up with mercury in his blood.

Clemence Tembo, Mining Agent (through translator):

I would wake up with a rash on my face, no taste in my mouth. Then I would have delayed speech and memory loss. So, this kept worsening over time, up until I became mute.

The doctor told me that I was very lucky to be alive. Had it been someone else, they would have died.

Nick Schifrin:

But he refused his doctor's suggested treatment.

Clemence Tembo (through translator):

I then asked him of the best way to get rid of heavy metal inside my blood, and he said, stay away from mercury. This was hard for me to accept because this is my job.

Nick Schifrin:

Zimbabwe ratified a U.N. convention that phases out mercury, and has its own law that bans mercury in or near rivers. But gold is vital to Zimbabwe's economy. It's Zimbabwe's largest export, and 60 percent comes from these unregistered miners.

Linda Mujuru:

The government is prioritizing the economic side of it, but also not prioritizing the health sides, the consequences that mercury has on people.

Nick Schifrin:

The government acknowledges that.

Danmore Nhukarume directs metallurgy in Zimbabwe's Ministry of Mines and Mining Development.

Danmore Nhukarume, Ministry of Mines and Mining Development: So, the convention does not say that you must eliminate the use of mercury, because, if we did that, the livelihoods of these miners you're talking about who are still using the mercury would now be — they would have to find some other source of livelihood.

Nick Schifrin:

There are alternatives with new technology. But Zimbabwe's government says it needs more money from the U.N. and more time.

Danmore Nhukarume:

It has really transformed from mercury use, reduction to mercury elimination. We will move with the miners in the communities, and we can only do that together. We cannot just prescribe that it stop.

Nick Schifrin:

But the government fails to implement its own ban, despite knowing the health risks.

Linda Mujuru:

When I visited the areas that artisanal miners are operating from, we see that they use mercury upstream, but, downstream, women and children, they fetch water that they use for drinking, for bathing, for cooking, and so forth.

So it's not really about the miners, we say, only, but it's also about the greater, bigger community that is within these communities where the mining is taking place.

Nick Schifrin:

And the risks that mercury poses are multigenerational.

Dr. Josephat Chiripanyanga is a surgeon at Chinhoyi Mall Medical Center.

Dr. Josephat Chiripanyanga, Chinhoyi Mall Medical Center:

Our main worry is the children and pregnant mothers. They're the ones that are most affected.

If a woman is pregnant and the baby that they are carrying is affected by the cyanide and mercury, they could be born with congenital deformities, birth defects.

Nick Schifrin:

But until there is an alternative, these unregistered miners will continue to flirt with fatal consequences.

For the "PBS NewsHour," I'm Nick Schifrin.