A UK television film says users of mobile telephones and other electronic goods are endangering some African ape populations.
The appliances use the mineral coltan, obtained mainly from the Democratic Republic of Congo (DRC).
Part of the country is the last stronghold of the eastern lowland gorilla, which the film says is in drastic decline.
It says a United Nations initiative to save the apes could prove a vital factor.
The film, No Hiding Place - Part Two, made by Television Trust for the Environment (TVE), is shown on BBC World in its Earth Report series.
Click here to watch BBC World and its report on the world's great apes.
TVE assesses the prospects for Grasp, the Great Apes Survival Project, launched by the UN Environment Programme (Unep) and Unesco.
Mineral frenzy
It says there is evidence suggesting that in the last five years the eastern lowland gorillas have declined by 80-90%, with just 3,000 or so animals left alive.
But eastern DRC is a war zone, where factions vie for power across the borders of Rwanda, Burundi and Uganda.
Coltan is used to make pinhead capacitors, which regulate voltage and store energy in mobile phones.
The spread of mobile phones across the world in recent years has led to a coltan boom in eastern DRC, home to 80% of the world's coltan reserves.
TVE says the price of coltan surged a few years ago from $65 to $600 a kilogram.
The British primatologist Ian Redmond says: "To work in the park, the miners have to pay one spoonful of coltan to the military, and one spoon to the local chief. That means about $15.
"There are about 15,000 people working here, each paying $15 per week to the military who control the region.
"That's something in the region of $1m a month going into the pockets of the militia."
Unwittingly, TVE says, the users of mobile phones and other devices incorporating coltan are contributing to the apes' downfall.
Dr Jane Goodall, renowned for her four decades of work with chimpanzees, tells TVE the problem has become acute in the last 10 years, as big logging companies, especially European ones, open up the forests.
Left hungry
She says: "Hunters from the towns go along the roads and shoot everything - elephants, apes, monkeys, bats and birds.
"They smoke it, load it on to the trucks and take it into the cities. It doesn't feed starving people, but people who'll pay more for bushmeat.
"The pygmy hunters who've lived in harmony with the forest for hundreds of years are now being given guns and ammunition and paid to shoot for the logging camps. And that's absolutely not sustainable.
"The animals have gone, the forest is silent, and when the loggers finally move what's left for the indigenous people? Nothing."
National asset
In Asia, TVE says, illegal logging and unsustainable commercial timber production have fuelled a sharp decline in the numbers of orang-utans.
Infants are highly prized in the international pet trade, but capturing them inevitably means the death of the mother, the film says.
Orang-utans, unlike other great apes, can be re-introduced to the wild. But forest loss is so bad that conservationists are trying to return them to partially cleared areas.
The film says great apes are a valuable economic resource for their host countries, because they attract tourists.
Jane Goodall tells TVE: "The bounty of the forest is gradually getting less and less and less.
"So the Grasp initiative is really crucial in spreading knowledge about the situation, which is very frightening."