Credit: Spencer Platt/Getty Images Small-scale mining companies in the Democratic Republic of the Congo often employ children.

A new report alleges material found in the batteries of popular tech gadgets may stem from child labor. The report, a joint venture between Amnesty International and African Resources Watch, tracked cobalt from mines in the Democratic Republic of the Congo to manufacturers that may include Apple, Samsung, Sony and Microsoft.

More than half of the world's cobalt, a main ingredient in popular lithium-ion batteries, comes from the Central African country, much of it from small-scale, "artisanal mining" that often employs children as young as seven.

“Millions of people enjoy the benefits of new technologies but rarely ask how they are made," said Mark Dummett, a human rights researcher at Amnesty International, in a statement. “The glamorous shop displays and marketing of state of the art technologies are a stark contrast to the children carrying bags of rocks, and miners in narrow manmade tunnels risking permanent lung damage."

The artisanal mines mentioned in the report are said to pay workers just $1 to $2 a day, as miners toil with basic tools in underground tunnels. Children often pick through leftover rocks and cobalt is then sold to intermediaries, who export it to China.

In 2014, UNICEF estimated around 40,000 children "worked for up to 12 hours a day in the mines, carrying heavy loads."

Amnesty tracked the material via public documents to importers and battery manufacturers in China and South Korea that claim to supply products to some of the world's largest tech companies.

Several companies, including Samsung and Sony, either denied a connection with cobalt from the DRC or declined to confirm or deny a link. Apple said it was "currently evaluating" battery materials, including cobalt, to determine if any child labor was involved in its supply chain.

Dummett told The Guardian it was worrying that many of the companies linked to the practices in the report were unable to identify where the cobalt used in their products was mined.

"No company can validly claim that they are unaware of the human rights and child labour abuses linked with mineral extraction in the region,” he said.“Anyone with a smartphone would be appalled to think that children as young as seven carrying out back-breaking work for 12 hours a day could be involved at some point in the making of it.”

You can read the entire report here.

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