If you own a mobile, it's probably held together by tin from the Indonesian island of Bangka. Mining is wrecking the environment and every year it claims dozens more lives

Suge doesn't have a mobile phone, so he uses a friend's to tell us the news: he doesn't want any visitors and he won't talk. His boss has told him not to say anything. They're neighbours and the mine's just up the road and he needs this job – the job he hopes to go back to when he gets better, inshallah – because mining is good money. Everything is OK. Just please don't come.

We leave at dawn. In the black morning sky the two-lane highway cuts west across the island towards Suge's village, a cluster of wooden and cinderblock houses near mangroves so deep the palm trees look like drowned bonsais. There are mosques with orange gates and lime roofs, clapboard shacks selling sweets to schoolchildren, and then, every so often, vast expanses of seeming desert.

At the bottom of the sandy dunes sit wide turquoise craters, looked over by gritty hills where haphazard tents made from tarpaulins and thatch serve as shelters for the men descending into the hollowed-out pools with pickaxes and buckets. Fifteen metres deep, they scavenge for tin, cutting into the sand with their hands and feet, just like Suge used to do, until one day in August his pit collapsed, burying him alive and snapping his left shin in half. His cries of "Longsor! Longsor!" – Landslide! – were drowned by the mud that killed the three friends who had been working beside him.

The tin that 44-year-old Suge has mined over the past 12 years on Bangka island – a granite outcrop just east of Sumatra in Indonesia – has been in heavy demand for the past few centuries. Bangka is a key point in its global trade. A long, boot-shaped belt of the metal stretches from Burma all the way down through Thailand, Malaysia, Singapore and Indonesia, with Bangka and its sister island Belitung comprising its toe.

When the Dutch colonised Indonesia in the early 19th century, one of their first tasks was to carve out vast mines on the island where locals and Chinese coolies worked side by side digging for dark specks of cassiterite – the main mineral in tin ore – to be used in alloys, conductors and tin plating. Today that same tin is mined for use primarily as solder in consumer electronics, according to tin industry group ITRI, holding together the circuit boards, transistors and resistors in items such as smartphones and tablets and mobiles. Around seven grams of tin goes into every mobile phone.

There is a chain here: Bangka and Belitung produce 90% of Indonesia's tin, and Indonesia is the world's second-largest exporter of the metal. A recent Businessweek investigation into tin mining in Bangka found that Indonesia's national tin corporation, PT Timah, supplies companies such as Samsung directly, as well as solder makers Chernan and Shenmao, which in turn supply Foxconn (which manufactures many Apple products). Chernan has also supplied Samsung, Sony and LG. So it is highly likely that the smartphone or tablet you use has Bangkanese tin in it, perhaps mined by Suge or one of the many tens of thousands of men like him, most of whom earn around £5 a day in a local industry that fetches roughly £42m of revenue for Indonesia every year.

It is still early morning when we knock on Suge's peeling front door, the village chief in tow to help him feel comfortable talking about his accident. Inside, Suge is propped up on a mattress on the floor watching soap operas, an overflowing spittoon at his side. Dangling from the rafters is the rope that keeps his leg elevated at night; today it whirls around his head like a noose not quite reaching its target.

Suge's father tells us that his son's accident was unavoidable. "The act of Allah," he splutters, "a big warning from God for him to change his life!" Suge is crying, spitting tears into the spittoon, moved by his father's accusation that he never prayed enough before the accident. He begins describing the crumbling wall of mud that enveloped him, the image of his young daughter propelling him to fight to the surface and take his first breath of air. "Look, mining has changed our community," he says, trembling. "People are wealthier now. They can send their kids to school."

But he knows that change is afoot. Two of his neighbours recently died while mining, bringing the unofficial death toll this year to 78, and the number of police crackdowns on informal miners has increased significantly in the past month. "We are on the cusp of a revolution here," Suge says quietly. "My accident was a small sacrifice to give happiness to people in the world, to give them phones and electronics." He begins likening himself to Napoleon Bonaparte, "the leader of the revolution", until his father cuts in suddenly: "It's silly. We are the ones producing the tin but we don't use it. We don't have handphones."

Suge describes being buried alive when a mine collapsed as, ‘a small sacrifice to give happiness to people in the world, to give them phones and electronics’. Photograph: Ulet Ifansasti/Friends Of The Earth

Official police figures show that mining accidents such as Suge's have quadrupled in the past two years, with the number of deaths increasing from 21 in 2010 to 44 in 2011. But activists say the number of dead actually averages around 100-150 every year, with many cases going unreported. Suge is lucky that his employer – a private mine operator that supplies tin to Timah – is paying him regular compensation and has offered to give him his job back once his leg heals. But compensation is a rare privilege in an industry in which most miners fend for themselves, says Ratno Budi of the Bangka-Belitung branch of Indonesian environment group Walhi. Suge calls the opportunity a "second life" and expects to begin mining again next year.

The word "dilemma" is the one most locals use to describe the situation in Bangka. Tin mining is a lucrative but destructive trade that has scarred the island's landscape, bulldozed its farms and forests, killed off its fish stocks and coral reefs, and dented tourism to its pretty palm-lined beaches. The damage is best seen from the air, as pockets of lush forest huddle amid huge swaths of barren orange earth. Where not dominated by mines, this is pockmarked with graves, many holding the bodies of miners who have died over the centuries digging for tin. Encircling the island are the dredgers and the suction ships and the thousands of illegal pontoons sucking up ore from the seabed like mechanised mosquitoes.

At 8.30am on a cloudy morning at Rebo beach, Alik, a lanky 35-year-old with shoulder-length hair and a wispy goatee, is looking out at the storm on the horizon with a beer in his hand. As the manager of 20 pontoons – makeshift rafts assembled from wood, thatch, plastic barrels and suction hoses – he is nervous. Soon there will be a meeting with the local government about turning Rebo beach into a tourism destination, essentially putting an end to the illegal mining his 80 men work at every day.

"There's no other work here besides mining," Alik says solemnly, pointing with his beer can out to sea. "Last year there were three suction ships just off the shore there. They sucked out almost all the tin, and so this year we have 75% less than last year." He sighs. "It's enough to get by but finding tin ore is like gambling. If you're lucky you'll find a lot and get rich for the day. If you're not, you earn just enough for a little food."

The beach is beautiful – arcing white sands intersecting in turquoise waters – but it is hard to imagine it as a tourist destination any time soon. The village is a smattering of fishing shacks frequented by stray dogs and chickens; the sand is littered with sweet wrappers, water bottles, flip-flops and polystyrene food containers; the sea is cloudy from the dredging.

Once the lifeblood of this beach, fishing is no longer an option, villagers claim. They say that large-scale seabed mining practised by private companies as well as Timah have damaged Rebo's fish stocks so severely that local fishermen have banded together in protest.

Their leader is Tjong Ling Siaw, a 40-year-old third-generation fisherman. For the past decade he has mounted one-man protests against seabed mining, and earlier this year he marched with members of his 600-strong association from the governor's office to parliament and Timah's sprawling headquarters in Bangka's capital, Pangkal Pinang. "We're calling for an end to all offshore mining – small-scale and large-scale – in the area," he says. "The water is cloudy now. There used to be fish and shrimp just three miles from shore. Now we have to go eight miles out and, for the big fish, 17 miles." He shakes his head and swats away a fly. "The government has spent a lot of money on local programmes teaching fishermen how to catch fish and giving us free engines. If they give us training on how to fish, then why don't they stop the mining?"

A short walk down the beach, a group of seabed miners are milling in front of their pontoons. Near them, a villager with bandy legs and a bulbous neck tumour is digging into the sand with half a white plastic plate and pouring it into a large bucket. When the bucket is full, he carries it over to a little pit of seawater and drags over what looks like a large wooden sled to start washing and separating the cassiterite from the grains of sand.

"If they stop the mining, I really don't know what I'll do," says Dulaksan, 54. "I'm getting old. I don't have enough energy to start fishing again." Without mining, people will become thieves, he says. Will he, too? "If there's no food to eat, sure. If the police catch me, at least I'll get a free meal and a place to sleep."

The seabed miners are also worried. "This is the only work we know how to do," says Mansur, 35, squatting in his yellow galoshes. "The tin is like a pulse – you have to follow it." He digs a hole in the sand to demonstrate how he and three co-workers operate. With just a mask and plastic tube connected to a compressor to supply them with air, they dive into the water, hoover up the sand with the suction hose, create a ditch to stand in, then turn the hose towards the newly created sea walls. "There's a line of white rocks and soil that you look for – the kong – and that's what you suck up."

Such practices are extremely dangerous. Umar, a childlike 30-year-old from Rebo with a maniacal laugh, was diving for tin in exactly the same manner when his four metre-deep underwater ditch collapsed around him, knocking away his mask and air tube. When he came to four days later, he discovered that doctors had spent hours pumping mud out of his lungs while he was still in a coma. Villagers at Rebo say accidents like Umar's were far more frequent in the past – sometimes causing as many as three deaths a month – but now many men stay on board, using long wooden pipes with hoses run off a generator to suck up the tin.

Edi, a sea tin miner, uses a bamboo raft to dredge for tin ore in Bangka, Indonesia. Photograph: Ulet Ifansasti/Friends Of The Earth

Whether they're diving or digging for tin, informal miners sell their day's findings on to middlemen, who also collect ore from miners working in official mines. The middlemen then mix the bags together to sell to smelters and companies such as Timah, or "whoever's offering the higher price", says Fitriyadi, 39, a middleman who operates from his home in south Bangka. "I don't ask where the tin comes from – all I know is that if there's a lot, they probably weren't controlled by the police."

After leading an investigation into tin mining in Bangka earlier this year, Friends of the Earth is now pushing the biggest smartphone companies, Samsung and Apple, to agree and implement a plan that will put an end to the human and environmental problems it causes. The demands are part of FoE's Make It Better campaign, calling for Europe-wide legislation that would require companies to report on their products' full human and social impacts – from accidents and pollution to how much water, land and raw materials they use. "Samsung and Apple have the power to help improve the situation [in Bangka]," says campaigner Julian Kirby. "Millions of us love our smartphones; this new mandatory company reporting would set us on track to also being able to love the way they're made."

In an emailed statement to the Guardian, Samsung said that it had recently "been trying to investigate sources of minerals in our supply chain" and added: "We will monitor the Bangka island situation to determine if an investigation into whether tin in our supply chain is being sourced from the region is required." At Apple, a spokesman said that the company's "commitment to social responsibility extends to the source of raw materials used in the manufacturing of our products. We require that our suppliers only use materials that have been procured through a conflict-free process and from sources that adhere to our standards of human rights and environmental protection." He did not clarify whether Apple sourced its tin from Bangka, pointing instead to a 2012 supplier responsibility report identifying (but not naming) 179 tin suppliers and 58 tin smelters.

LG, meanwhile, told the Guardian that it "takes the Friends of the Earth investigation seriously and believes that this issue requires action at an industry-wide level". A Sony spokesperson said its 2005 code of conduct "expects" suppliers to agree and adhere to "respect for human rights, environmental conservation and health and safety", and pointed to an online report on responsible sourcing, which says: "Sony supports and contributes to industry initiatives such as the traceability project for tin launched in 2010 by ITRI… to validate that the metals used in its products are not contributing to conflict and come from sustainable sources."

To say that mining is everywhere on Bangka seems an exaggeration until one studies the numbers. Government officials estimate that roughly 20% of Bangka-Belitung's 1.3m islanders are miners, with a further 40% involved in related industries – working in the smelters, for example, or trading as middlemen, or selling generators. There are mines in backyards, mines in the forest, mines on the side of the road, mines out at sea. Unofficial miners scrape for tin next to official bulldozers at a 5,000-hectare mine operated by Timah. The vast government compound in Pangkal Pinang is built on a reclaimed mine, and even here men with pickaxes can be seen digging when officials aren't looking.

At the provincial tourism office in the government compound, framed photos of beaches hang next to those of mines, the bright blue sky reflected in their stagnant pools. The irony is not lost on director Yan Megawandi. "For tourism, mining is a big problem." He sighs. "Tin mining has been exploited here for more than 200 years, so changing people's mindsets is really a challenge for us." He unfolds a map of the island and lays it out on his desk. "The eastern beaches of Bangka are the best on this island. But they're also very rich in potential tin. When there's mining in front of [Bangka's best hotels], it's noisy and the water becomes dirty. Tourists complain to the hotel, and the hotel complains to me." He clasps his hands together to explain the difficulty of his position. "We have no power to stop the mining here. I can only suggest to mining officials or the local police or journalists that we stop the mining."

An hour north of Megawandi's office, down winding lanes lined with trees that obscure the mining pits just a few metres either side, lies Parai Beach Resort & Spa, a four-star resort with cabins perched under palm trees, a long sandy beach and views out to a glittering sea. Despite a location on one of Bangka's most popular beaches, occupancy here is down 90% – all because of the seabed mining last year, according to manager Edy Mulyana.

"The government said there would only be one or two ships, and that they'd be far from shore, but actually there were 20, 30, 40 ships – so many I couldn't count," he says. "The ships were loud, the smell was bad and the water was cloudy and dirty. No one wants to vacation if they can't swim."

Some 35 companies are involved in mining in Bangka-Belitung, and mining and related industries account for roughly 60% of the province's revenue, says Bangka-Belitung's head of mining and energy, Aldan Djalil. Tourism now brings in a mere fraction of what mining earns – just £810,000 compared with mining's £42m, according to 2011 figures – but I ask Djalil whether tourism could trump mining in the future. He takes out a laser pointer and aims it at a triptych of badly hung wall maps in his office. "This is good view, here good view," he says in English, his red laser dancing across the pink splodges of official mining zones. "But so much potential for tin!" he laughs gleefully. He adjusts his tracksuit bottoms around his pot belly and then says with gravity: "Before there were hotels, there was tin."

Government officials such as Djalil, as well as industry officials, are aware that tin ore on Bangka will soon run out. This explains Timah's current strategy, "Go offshore, go deeper", as well as the newest addition to its offshore fleet: a massive bucketwheel dredger with a long, chainsaw-like arm that can churn up tin ore from 70 metres below the seabed, nearly twice as deep as the current dredgers manage.

The extent and severity of the mining both on- and offshore have resulted in massive changes to the geology of Bangka and to its food chain. While there have been some environmental successes – in Belitung last month, 10,000 protesters called successfully for a revocation of seabed-mining permits – more than half of Bangka's coral reefs are now in critical condition, according to Walhi. On land, the pits' stagnant pools of water become breeding grounds for dengue fever and malaria. Tin mining typically requires land to be bulldozed, then hosed down and dug up, meaning that the fertile topsoil so essential for agriculture and plantations is lost, and acidic soil brought to the surface instead.

Aware of the problems, the government is now looking at solutions. A draft law to be signed by parliament in December would refocus the provincial budget away from mining and on to agriculture, fishing and tourism, funding rubber and pepper plantations and boosting infrastructure, according to Didit Srigusjaya, a local MP who sits on the parliamentary regulations commission. There's also a new edict from the central forestry ministry whereby communities will be able to bulldoze up to a fifth of the forest in their locality for agriculture or plantation use. While this may bring some people back to farming, however, cutting down more trees is not a beneficial long-term strategy, according to Walhi's Budi, who claims that 77% of Bangka's forests are already in critical condition.

Under current legislation, all former mining pits are required to be turned into reclamation projects like farms and plantations, but a drive around the island shows that most are either left abandoned or are still being exploited by groups of informal miners, many of whom sleep and eat on site under makeshift tents. Sometimes a newly planted banana tree can be seen sticking up out of the thick mud, its yellowed leaves withering in the sun.

Timah, which operates 510,000 hectares of on- and offshore mining concessions, says that its new policy is to focus on the environment. Where once the company hired subcontractors who could mine where they chose, under new regulations the location and duration of their activities must be controlled directly by the corporation.

"The new programme is designed to save the environment," says spokesman Agung Nugroho, explaining that the changes will allow Timah to better control the damage wrought by mining. But it seems that this new policy may in fact be a smokescreen to increase profits. Nugroho admits that Timah is losing money to informal miners and companies that collect tin ore from its mines but sell it on to others. "We have the biggest mining area, but we are not producing the most tin," he complains. "Our deposit is being stolen."

It is this complaint – rather than calls for better safety controls – that has seemingly forced the police to clamp down on the island's informal miners. Under the leadership of Bangka-Belitung's new police chief, Budi Untung, police have made the same number of arrests in the past five weeks as they did in the previous nine months.

"We want to change the community mindset so that mining isn't the only focus of income – there's agriculture, plantations, other jobs to do here," says Untung, 54, from an office so huge it encompasses four sofas, various planters and orchids, and a flatscreen TV.

Disused mines will be patrolled and turned into reclamation sites, Untung says, with the miners who disobey arrested and possibly sent to jail. "People's mindsets about tin will change because of the price one day. Coal today is very cheap and tin one day will have a low price, too."

In the six days I am on Bangka, I see just one police raid. The generator the informal miners use to both wet the sand and suck it up out of the mine has sputtered to a stop as the officers warn them not of the risks they are running, but of the damage they could do to the highway 100 metres away. "The road could collapse," the officer says. "This is a warning, otherwise we will confiscate your equipment."

Timah says that it offers health and safety training to its employees and subcontractors (Suge confirms that he underwent such training with his employer) and that its mines must be dug in terraces to diminish the possibility of a landslide. But many mines on Bangka are dug straight down, and no one – from the police chief to Walhi to government officials – has ever heard of a mine owner being prosecuted for dangerous practices.

When asked who is responsible when a death or injury like Suge's takes place in a mine run by a subcontractor supplying tin to Timah, Nugroho says, "If they work for us, then all the health and safety is checked by us. People can make mistakes and when we investigate, it can be settled by us and that company." Does that mean prosecution, or an economic settlement? "It is settled," he repeats without clarifying, but says it is in accordance with government law.

Death and injury are part and parcel of this job, Suge says. "Every job has its risks."

His wife looks forlornly away. "Everyone's husband works in the mines," she says when asked if she's worried about her own. "I just feel lucky he survived the accident."

Suge expects it to take a full year for the bones of his leg to heal. He needs a new pair of crutches – his old-fashioned wooden ones are an uncomfortable way to get around – so when he calls to thank us for the small sum of money we gave him to purchase new ones, I'm not surprised.

"Hey! Thanks for the donation," he cries. "But I used the money to buy something else – a mobile phone!"