A businesswoman who styled herself as the “Queen of Trash” has gone on trial in Sweden accused of illegally dumping mountains of waste, in the country's biggest-ever environmental crime case.

Bella Nilsson is one of 11 people charged with “aggravated environmental crime”.

She was chief executive of waste management company NMT Think Pink, which is accused of dumping or burying 200,000 tonnes of waste in 21 locations between 2015 and 2020.

Lawyers for Ms Nilsson who is now called Fariba Vancor, and another former chief executive Leif-Ivan Karlsson say they deny any wrongdoing.

Entering Attunda district court north of Stockholm, Ms Nilsson refused to answer reporters' questions.

Prosecutors said the way the company mismanaged the waste led to harmful levels of carcinogenic chemicals, lead, arsenic and mercury being released into the air, soil and water.

In one incident, a Think Pink waste pile close to a nature reserve burned for two months after spontaneously combusting.

Ms Nilsson has previously told Swedish media that her company acted in line with the law.

Prosecutors said that NMT Think Pink – which went bankrupt in 2020 when Bella Nilsson was arrested - had “no intention or ability to handle [the waste] in line with environmental legislation”.

The way the rubbish was discarded at the sites endangered the "health of humans, animals and plant life", they added.

Think Pink was hired by building companies, municipalities and private individuals, to dispose of everything from building materials, electronics, metals, plastics, wood, tyres and toys. But it left the piles "unsorted" and abandoned, according to prosecutors.

All 11 defendants have denied wrongdoing. They include Bella Nilsson’s ex husband Thomas Nilsson, whose lawyer said that as chief executive before 2015 he had was not in charge when the offences were committed.

A preliminary investigation into the scandal ran to 45,000 pages.

Prosecutor Anders Gustafsson argues that as well as dumping waste, the defendants used falsified documents to mislead authorities and make money which was used for private purposes.

Several municipalities are seeking damages of 260m kronor ($25.4 million) for cleaning up the mountains of waste as well as decontaminating the sites.

Botkyrka council, south of Stockholm, has sought 125m kronor in damages, having spent far more than that merely on removing the waste.

One fire in Kagghamra forced parents to keep their children indoors for miles around because of toxic smoke fumes.