The Catholic archbishop of Dublin has removed trainee priests from Ireland's largest seminary over allegations of widespread use of the gay sex app Grindr and the failure of the authorities to properly investigate it.

The move is the latest scandal to hit the Catholic Church in Ireland, once the defining influence on public life, but now humbled by reports of child sex abuse stretching back decades and of church leaders' complicity in covering them up.

Archbishop Diarmuid Martin said a series of anonymous allegations about a gay sex culture at the Maynooth seminary, where over 50 students are training to be priests, had been compounded by the college authorities' failure to investigate.

"One (allegation) is that there is a homosexual, gay culture, that students have been using an app called Grindr, which would be inappropriate for seminarians and not just because they are going to be celibate priests," Martin said in an interview with Irish state broadcaster RTE on Tuesday.

"If this is going on a large scale in the seminary and it hasn't been noticed in the seminary, then there is something wrong," he said.

He said there were also allegations that students who had spoken to the authorities had been dismissed from the seminary. A series of anonymous allegations and counter-allegations had poisoned the culture at the college, he added.

The president of the seminary, Hugh Connolly, said no investigation had taken place because there had been no official complaint.

"It is very important that anything we do, we do in natural justice, in other words, that we will always act only when we have clarity and when we have grounds to act," Connolly told RTE. "Broadly speaking, I think the atmosphere is a very good one."