a new investigation has found that the recycled lead purchased by U.S. battery manufacturers is linked to dangerous lead poisoning from the source, Nigeria, which uses recycling methods anyone with 10 minutes of education on lead exposure, would avoid.

The New York Times and a nonprofit newsroom called The Examination followed the supply chain of U.S. car batteries over the course of a year from a town near Lagos Nigeria where factories recycle lead, to the US where stricter regulations in the U.S. that have driven smelters out of business because Americans have put regulations in place because we don't want lead poisoning in our midst in the United States, combined with growth that has produced demand for lead that's exceeded what the domestic plants can get. 

Batteries get picked up by the pickers that go around Nigeria, finding spent batteries they buy, bring to the yards where the breakers use machetes to break apart the plastic casing.

Then they use their bare hands typically to pull out the lead from inside. And then that lead gets hauled off by truck to a bunch of factories, smelters, in this one town of Ogijo, the lead gets melted down to liquid form.

And the result of this is lead poisoning the local area being downwind of the atomized particles in the atmosphere. 

Nigeria is the fastest growing source of a small percent of recycled lead that's being exported to the U.S. because though large American battery manufacturers would prefer to recycle spent batteries in the region, and it's cheaper to rely on the domestic supply chain, because the scale is so huge and they already have their plants in place.

But growth has produced demand for lead that's exceeded what the domestic plants can get. So they have gone out around the world looking for other sources of lead to supplement what they have got, and Nigeria is one of scores of countries that are now supplying this recycled lead to the U.S. to be folded in to batteries.

https://www.pbs.org/newshour/show/recycled-lead-used-in-u-s-auto-batteries-linked-to-poisoning-in-african-communities