A cooking oil that is driving the destruction of the rainforests, displacing native people and threatening the survival of the orangutan is present in dozens of Britain's leading grocery brands, an investigation by The Independent has found.

Palm oil – blamed for a tree-felling rampage in south-east Asia – is present or suspected in 43 of 100 best-selling brands in UK, far more than the one in 10 products estimated by Friends of the Earth four years ago.

Palm oil is present in Hovis and Kingsmill bread, the country's best-selling margarine Flora, KitKat and Cadbury Dairy Milk chocolate bars, as well as Dove soap, Comfort fabric conditioner and Persil washing powder.

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The research – the first time palm oil, which is usually labelled as "vegetable oil", has been definitively quantified in British products – comes amid a surge in demand for the world's cheapest cooking oil.

The United Nations Environment Programme believes palm oil is the major driver of deforestation in the vast islands of Borneo and Sumatra. Hundreds of thousands of acres of forest are cleared to make way for plantations from which 90 per cent of wildlife disappear, including the orangutan, which is fighting a losing battle against extinction. Orangutan numbers have dwindled by 90 per cent since 1900, with the rate of loss accelerating in recent decades.

Emissions from the chainsawed peat-rich forests of Indonesia (which owns Sumatra and half of Borneo) are also thought to generate 4 per cent of global greenhouse gas emissions.

At present only 4 per cent of palm oil production is certified sustainable by the Roundtable on Sustainable Palm Oil (Rspo), meaning that the vast majority of global supply is linked to the forest gold rush. All companies contacted by The Independent said they were talking to suppliers about moving to a sustainable supply.

However most of them – including Cadbury, Kellogg's Nestlé, Mars and Heinz – have set no date for the process. Nestlé said: "Nestlé shares concerns about the serious environmental threat to rainforests in south-east Asia and supports an end to deforestation. Palm oil is not a major raw material and... the company's use of palm oil has been declining somewhat."

Mars said: "We do use palm oil in our chocolate, but only work with suppliers who respect the environment and are committed to working with all stakeholders to make progress towards sustainable production."

WWF, formerly the World Wildlife Fund, called on manufacturers to start matching rhetoric with reality by buying sustainable oil, which costs between 10 and 35 per cent more than ordinary supplies which are mixed at refineries.

Jan Kees Vis, Rspo chairman, said that manufacturers did not want to pay more for a hidden ingredient. "The volume of certified palm oil traded is disappointingly low so far, the reason for this being that many companies are not prepared to pay a premium for certified oil," he told The Independent.

Originating in West Africa, palm oil has become a £14bn-a-year industry. Some 38 million tonnes are produced annually. Manufacturers use the oil to bind and bulk out chocolate, biscuits, bread and margarine and to give a creamy consistency to soaps.

About 85 per cent of the global supply comes from Borneo and Sumatra, where corruption is rife and where incursions into the forests are enforced by gun-toting security guards.

Satellite pictures have shown the rapid loss of the islands' rainforests, which, in addition to the orangutan, contain endangered species such as the clouded leopard, Sumatran tiger, and sun bear. Survival International, the London-based human rights group, says that palm oil producers supplying world markets are evicting indigenous people such as the Penan in Borneo from their land. In an interview taped earlier this year in Borneo, a Penan villager recalled: "There were no official discussions. The company just moved in and put up signs saying the government had given them permission to plant oil palm on our land. The manager promised he would pay us whatever we wanted. But we already know that the companies lie... If oil palm is planted, we will lose our land... there will be no more forest."

Global demand for palm oil is rising at between 6 and 10 per cent a year. Although yields could be raised to meet the demand, suppliers have a financial incentive to chop down forest for hardwoods for furniture, which subsidises the plantations before the first oil is produced.

If current rates of logging continue, the UN Environment Programme estimates that 98 per cent of forests in Indonesia may be destroyed by 2020.

Around 16 per cent of global palm oil arrives in the EU. Companies often refuse to disclose whether their products contain palm oil.

However, after piecing together information from the companies, The Independent has established that palm oil is contained or suspected in 43 of the Top 100 grocery brands. Of the nation's £16bn spending on the top 100 brands, £5.5bn goes on brands which contain, or are suspected to contain, the oil. Thirty-three out of 62 food brands contain palm oil.

Only a few British firms, including Unilever and Sainsbury's, have bought large amounts of Rspo-certified oil.

Green Palm, a Hull-based company which trades Rspo certificates, says it has struggled to find corporate buyers. The Food and Drink Federation said the UK was "a small player in the complex global market for palm oil", importing only 1.2 per cent of the annual crop for manufacture here.

Andy Tait, Greenpeace's forests campaigner, said: "If you buy products from Unilever or Nestlé, ask what measures they are taking to remove unsustainable palm oil from their supply chain. Public pressure makes companies change."

Ancient oil: Modern uses

* Palm oil is made from the fruit and seeds of the oil palm (elaeis guineensis), an edible plant long used as a cooking oil by villagers in West Africa, which now has a wide range of industrial applications.

* Palm oil is so prized because in addition to being the world's cheapest, it is "uniquely fractionable". Chemical processes can separate solid (stearin) and liquid (olein). Manufacturers use the versatile oil in a wide range of foods and household products and, increasingly and controversially, it is used as a biofuel.

Household names: Big brands and palm oil

Kellogg's (US) Uses palm oil in 50 products, mostly cereal bars but also cereals such as Special K and Crunchy Nut, where it binds together clusters. Does not buy sustainable palm oil.

Cadbury (UK) Pours palm oil into chocolate bars, including Cadbury Dairy Milk, where it is listed as vegetable oil. Uses 40,000 tonnes a year, none certified as sustainable.

Mars (US/UK) Uses palm oil in Mars Bars, Galaxy and Maltesers, where it is labelled "vegetable fat". Does not buy sustainable palm oil. Says it wants to.

Procter & Gamble (US) Makes Ariel, Daz and Fairy Liquid, where use of palm oil is suspected but unproven. Says it will have a sustainable supply by 2015.

Unilever (UK) World's biggest user of palm oil, which is found in Flora margarine, Pot Noodle, Comfort and Persil. Buys 1.6m tonnes a year – 4.2 per cent of global production. Acknowledging the damage to its reputation and the environment, Unilever set up the Roundtable on Sustainable Palm Oil.

Kraft (US) Says it does not use palm oil in Dairylea cheese but does in other products. Buys half a per cent of global supply. Says it will move to sustainable palm oil by 2015.

Heinz (US) Uses palm oil to fry potatoes for Aunt Bessie's Potatoes, which it makes under licence.

United Biscuits (UK) Uses palm oil across its range including McVitie's Digestives and McCoy's crisps. Says it is reducing quantities.

Nestle (Swiss) Palm oil in KitKat, Quality Street, Aero and other brands.

Premier Food (UK) Uses in Hovis, Mr Kipling Cakes, Bisto Gravy and Cadbury cakes (made under licence). Hopes to move to a certified sustainable supply by 2011.

Pepsico (US) Makes Walker's crisps. Has one of the best corporate policies, only using palm oil in Quaker Oat Granola and Nobby's Nuts. Intends to phase out use on those two products.