SEOUL, South Korea — Samsung admitted this week that the tin contained in its mobile phones may be from a mine that has used child labor.
The tin comes from a mine on the Indonesian island of Bangka that is controversial for its labor and environmental practices, the Guardian reported.
"While we do not have a direct relationship with tin suppliers from Bangka Island, we do know that some of the tin that we use for manufacturing our products does originate from this area," Samsung said in an email to customers.
"We are also undertaking a thorough investigation of our supply chain in the region to better understand what is happening, and what part we play."
The admission by Samsung came after a campaign by the human rights group Friends of the Earth (FOE).
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Samsung received complaints from 16,000 customers after the campaign.
It's not the first time tin and tin mining in Bangka was condemned for its unsavory practices.
A Bloomberg Businessweek report last summer highlighted those practices at the mine where one third of the global tin supply comes from.
The Guardian also conducted an investigation into the mine that played a key role in prompting the FOE campaign.
Craig Bennett of Friends of the Earth said in a statement after Samsung's admission: "Millions of us love our smartphones and couldn't do without them - we want to be able to love the way they're made too."
Samsung has long been suspected of exploiting cheap labor and tolerating poor working conditions at its factories even in South Korea, a developed democracy.
Many former Korean workers have been diagnosed with brain tumors and leukemia at Samsung semiconductor plants, which make the chipsets that go into all sorts of smart phones, including those manufactured by Apple. Rights groups say the Korean government and Samsung have refused to fully compensate the victims.
The company denies its plants are dangerous.