Monday, May 29, 2017

Zambia's Lead Poisoning

Kabwe is the world’s most toxic town, according to pollution experts, where mass lead poisoning has almost certainly damaged the brains and other organs of generations of children – and where children continue to be poisoned every day. A large World Bank project that ended in 2011 revealed the problem, though it achieved little in remediating the pollution. In affected townships, the lead in soils is about 10 times the US safety limit and far higher in hotspots.

“Having been to probably 20 toxic hotspots throughout the world, and seeing mercury, chromium and many contaminated lead sites, I can say the scale in Kabwe is unprecedented,” says Prof Jack Caravanos, an environmental health expert at New York University, on his fourth visit to the town. “There are thousands of people affected here, not hundreds as in other places.”  Llead poisoning stays with you for the rest of your life – it can’t be reversed. Having seen the extreme lead levels measured in children in several townships, he says severe and widespread health impacts are highly likely, including brain damage, palsy and ultimately fatalities. “I am concerned kids are dying here,” he says.

Almost a century of lead mining and smelting has left a truly toxic legacy in the once-thriving town of 220,000 people in central Africa’s Copperbelt, 100km north of the capital Lusaka. The fumes from the giant state-owned smelter, which closed in 1994, has left the dusty soil in the surrounding area with extreme levels of lead. The metal, still used around the world in car batteries, is a potent neurotoxin and is particularly damaging to children. But it is youngsters who swallow the most, especially as infants when they start to play outside and frequently put their hands in their mouths. 

But the real impact on Kabwe’s people is yet to be fully revealed and, while the first steps towards a clean-up have begun, new dangers are emerging as desperately poor people scavenge in the vast slag heap known as Black Mountain. On Black Mountain, bare-foot and ragged-clothed men dig out lead from the huge slag heap, often in long, unsupported tunnels, dug with hand tools and lit only by candles. “When you don’t make them properly, you find they just bury someone,” says Provost Musonda, a young father of three, and people have died in the scarred hellscape of Black Mountain. He earns about 80 kwacha ($8.50) a day, unless his chest pains prevent him working. “If I could get another job, I would go there. But there is no way of sustaining our lives otherwise.” Caravanos uses a portable detector to measure the lead levels on Black Mountain: they are sky high at 30,000-60,000 ppm. “Kids playing here is really unbelievable,” he says, noting the youngsters nearby. At one spot, a young woman, Debola Kunda, toils away, with two of her young children lending a hand. The dust sparkles with the metallic glint of galena – pure lead sulphide – and the soil right next to her four-year-old son, Acili, measures an astronomical 37,900ppm – 100 times above the danger level.

The blood levels of lead in children in Kabwe are  known to be very high - a recent study revealed that every one of 246 children tested were above the safety limit of 5 micrograms per decilitre of blood. The vast majority were over 45 micrograms per decilitre, which causes brain, liver and hearing damage, and eight were over 150 micrograms per decilitre, at which point death is the likely outcome.

Annie Kabwe, first noticed her children getting stomach pains and fevers, and losing weight. “I thought it might be HIV, but the tests were negative,” she says. Then blood tests revealed very high levels of lead. “I thought they would die,” Kabwe says. After learning about the toxicity of the dust in her neighbourhood and reducing her children’s lead exposure, through frequent washing of hands and clothes, the worst has not happened. “The problem is they are not really learning well in school, so the lead is still affecting them,” she says.
The slow, insidious nature of lead poisoning means careful epidemiological work is needed to distinguish its effects from other causes and reveal the true extent of the crisis. But that work has barely begun. “It is shocking to think that we are here in 2017 and that problem we have known about for decades is still here,” says Caravanos.
One such hotspot turns out to be the dusty yard of the only medical clinic in Chowa, the township that once housed the mines and smelter workers, which serves 14,000 people. Caravanos uses a handheld detector to reveal extreme lead levels in the sun-baked mud, frequently over 10,000 parts per million (ppm), far above the 400ppm limit in the US.

No comments: