An Indonesian scientist whose work proves that companies are illegally burning forest to grow the palm oil used in foods and cosmetics has received a British award in recognition of the huge risks he has taken.

Bambang Hero Saharjo, from Bogor Agricultural University, has been sued, threatened and intimidated because of his work identifying the companies behind the fires that ravage what remains of the Indonesian wilderness.

Greenpeace has warned that in buying goods ranging from shampoo to margarine British consumers inadvertently support illegal land clearance. All these products contain palm oil and the charity has linked those of conglomerates such as Unilever and Nestlé to “devastating” fires.

Professor Saharjo, who has worked on the front line in stopping these fires, has been given the Maddox prize, a British award for researchers who take personal risks in the cause of science. He has been the expert witness in hundreds of cases against palm oil companies, proving that they started fires to clear land on the cheap.

He said: “Seventeen companies we investigated in order to know whether they were compliant. None were. Are companies really sustainable or are they merely paying lip service?”

“It has made me very powerful, to fight this environmental destruction,” says Bambang Hero Saharjo, pictured here on the front lines of a burn.

Greenpeace said that the idea of “certified sustainable palm oil” was a con by “supermarkets and big brands attempting to distance themselves from deforestation”. Much of it is grown in Indonesia but to get new agricultural land means clearing forest and peatland. The cheapest way is by fire, causing considerable air pollution.

An Indonesian scientist’s work proves that companies are illegally burning forest to grow the palm oil used in foods and cosmetics.

Proving that the companies start the fires requires forensically tracing them to their source. Courts need expertise to do that and in an atmosphere of intimidation Professor Saharjo is the only one prepared to give it.

“These men phone me,” he said. “They say, ‘Bambang, be careful, if you continue this kind of work, you and your family will be in trouble.’ They ask me to stop, they intimidate me, they even threaten to kill me.”

Now that the scientific journal Nature and Sense About Science, a UK charity, have jointly awarded him the prize, he said that it would make him better able to withstand the threats.

“I have spent years alone, working in the field. Now I’m very happy because I’m not alone. I have supporters. So it has made me very powerful, to fight this environmental destruction.”