If any words trigger the ITV bosses in charge of the network’s reality television output, they are ‘toxic’, ‘exploited’ and ‘lawyers’.

Those three terms have certainly been used more than once this week in ITV’s west London headquarters, as the broadcaster struggles to contain its latest fall-out.

Because what was expected to be the latest hit from the network’s golden goose franchise, I’m A Celebrity, has instead turned into a multifaceted legal and reputational nightmare after clashes between celebrity contestants.

The spin-off show, I’m A Celeb South Africa, which concluded last week with TV star Adam Thomas being crowned king of the jungle, will better be remembered for his furious rows with fellow contestant former footballer Jimmy Bullard.

In one episode, an enraged Thomas was seen swearing at livewire Bullard, and in footage that wasn’t aired even called him the ‘c-word’.

So ferocious has been the aftermath of the on-screen row that insiders at the channel fear the gloss has come off the programme, which still attracts more than six million viewers.

My source tells me: ‘There are genuine fears that I’m A Celeb will not recover from this horrible example of male aggression. That’s not what the show is about. In recent years it has become quite the opposite, it’s been much more feelgood.

‘This is like something out of the early Noughties when reality TV was very dark.’

All this came after an episode aired last week, during which Bullard decided to stop a trial he was taking part in alongside Thomas, saying he ‘didn’t have it in’ him and shouted the catchphrase which halts proceedings: ‘I’m a celebrity… get me out of here!’

All just part of the game, one would think. Not so for Thomas, who quickly became incandescent and screamed at Bullard: ‘Are you f***ing taking the p***?’

He then shouted: ‘I am in there getting covered in f***ing ants!’

Bullard, 47, then told Thomas to calm down.

It was then, in footage which was edited out, that Waterloo Road star Thomas called Bullard the c-word.

Part of Thomas’s rage seemed to be because this time all celebrities were competing in pairs with the losing pair forced to leave camp.

Therefore Bullard’s decision to forfeit the trial meant that Thomas would also be forced to leave the camp.

However, hosts Ant and Dec then introduced a twist allowing campmates to vote on keeping Thomas – which led to him remaining on the show, and eventually winning the contest.

Bullard has now instructed lawyers to sue ITV.

And I can reveal that Bullard made recordings during the live final which he will be using in his legal action against ITV.

During the advert break, the former footballer recorded himself asking fellow celebrity contestants singer Sinitta, former football manager Harry Redknapp and actor Craig Charles if they thought Thomas’s behaviour had crossed the line. All agreed he had.

Bullard is aggrieved because in the show’s contract there is a section on misconduct which states that if a celebrity displays aggressive behaviour, they should be immediately kicked off the show.

However, despite Thomas’s outburst at Bullard, ITV allowed him to continue filming.

Bullard, who is known for calling a spade a spade, strongly believes that 37-year-old Thomas’s verbal outburst was aggressive, and so breached his contract. I’m told he also believes Thomas should never have been allowed to win the show.

A source close to Bullard tells me: ‘Jimmy wasn’t going to attend the live final but then changed his mind when he realised it would give him the opportunity to speak to the other celebrities.

‘[The boxer] David Haye has already been vocal about the way Adam Thomas was edited during the show, but he wasn’t there when he kicked off at Jimmy.

‘So Jimmy asked Harry, Sinitta and Craig during the final and recorded their answers. They all witnessed Adam’s outburst and agreed he’d crossed the line.’

So not only do ITV have a scandal where one of their top shows appears to be less than fragrant, but with the threat of legal action, it doesn’t look like these accusations are going away any time soon.

‘ITV know how to get the viewers in, but this has backfired spectacularly,’ says my source.

‘I’m A Celeb is in deep crisis. It’s a family show – ITV prides itself on this.

‘Now it’s become a terrible example of masculine toxicity. It all became extremely aggressive, ITV know that. There have been many meetings about how to deal with it.

‘There are conflicting views, of course. But one thing everyone agrees on is it’s a mess.’

To add to the turmoil, hosts Ant and Dec have also been dragged into the argument – something they are furious about.

While they were excited at the prospect of a new challenge with the live show filmed at the Versa studios in Acton, west London, last Friday, I am told they are ‘very cross’ at what they saw as a lack of professionalism that night.

‘Ant and Dec are the ultimate professionals,’ says my source at the network. ‘They have always created a positive and happy working environment. Of course they love good telly, and the odd feud and rift, but this got completely out of control.

‘They were visibly furious last Friday and have been since. They didn’t like the atmosphere and hated how it was allowed to escalate the way it did.’

Ant, in particular, was said to be angered that Bullard didn’t seem to want to let sleeping dogs lie in the live show.

The presenter stunned viewers by going up against Bullard, claiming the only reason they hadn’t screened his full outburst is because ‘c bombs are un-broadcastable’.

However, Bullard then replied: ‘Absolutely! But it is abusive, aggressive and intimidating what happened.’

Appearing rather perturbed by his response, Ant then went on to explain that he didn’t think Thomas had been intimidating.

In the advert break Dec had what was described as a ‘terse’ conversation with Bullard.

After filming Ant was seen, furiously vaping, flanked by security guards as he was approached by Bullard who looked like he was very angry in photographs taken of the moment.

The pair also spoke to contestant boxer David Haye who, to add to ITV’s woes, says he is also suing ITV for £10million as he believes his brand has suffered ‘irreparable damage’ because of his presentation in the final edits.

Perhaps understandably, ITV’s press team were not answering their phones this week as the crisis spiralled.

For his part, Thomas broke down this week while talking to his brothers Ryan and Scott on their At Home with The Thomas Bros podcast, and claimed Haye wanted to ‘break’ him.

In the lead-up to last weekend’s final, Thomas had also spoken again about living with psoriatic arthritis.

On the podcast, he said: ‘I just felt like I’d been exploited and I think you can see it at the end of the live show… I feel like I sold my soul and you couldn’t pay me £10million to do that experience again. Nothing is worth what I went through in there.’

His protective twin Scott was intent on blaming the broadcaster, insisting: ‘All those campmates were p***** off at ITV. It wasn’t your issue. It is ITV’s issue.

‘In those shows, you get eaten alive, because it is so toxic. This is what is cut-throat about these shows: they are so high-risk. It wasn’t your fault, it was the way ITV played it.’

However, my source told me: ‘Adam breaking down on the podcast and talking about how awful it was for him has further enraged Jimmy.

‘Jimmy is raging with ITV for not showing the footage and editing Adam to look like a nice guy when he wasn’t like that at all.

‘He also noticed he was posting about his condition just days before the final in a bid to get more sympathy. He just doesn’t believe that the public have seen what Adam is really like.’

And so Bullard and his legal team are studying his contract with ITV – particularly the part about misconduct – to see where it leaves them.

‘They have been going over it all and what Adam did with his behaviour,’ says the source.

‘So the fact that not only did ITV change the rules to get him back on the show, they too are breaching contract because he should have been kicked off for the way he acted. This really is just the beginning of it all, and it’s going to get even nastier.’

Inside ITV, staff are confused at bosses allowing such behaviour to be tolerated – especially considering how vocal they have been about supporting the mental health of reality TV contestants, following the suicides of two Love Island contestants, Mike Thalassitis and Sophie Gradon.

After their deaths, ITV launched a mental health campaign – ironically fronted by Ant and Dec – called Britain Get Talking.

‘The aggression and abuse isn’t really what ITV claims to be about,’ says one insider connected to the broadcaster.

‘It all felt very 2005. There are a few disconnects going on here.’