A mission was launched on this week off the Italian coast to investigate what anti-Mafia investigators have long suspected was a conspiracy between organised crime, industrialists and government agencies to dump nuclear and other toxic waste in the Mediterranean and off Africa. An Italian marine survey ship under police protection started tests 12 miles off Calabria’s coast on the wreck of a cargo ship 500 metres below.

According to Francesco Fonti, a Mafia turncoat, the ship was scuttled in 1992 carrying 120 barrels of toxic materials – much of it possibly radioactive. The ship, identified by Mr Fonti as the Cunski, is one of three vessels carrying toxic cargoes he says he sank as a service provided by the ’Ndrangheta, the Calabrian Mafia.

Over two decades Italian prosecutors have looked into more than 30 such suspicious deep-water sinkings. They suspect that Italian and foreign industrialists have acted in league with the Mafia, and possibly government agencies, to use the Mediterranean as a dumping ground. Vessels sank in fair weather had suspicious cargo, sent no mayday or the crew vanished. None had been located, until now.

Fishermen and political leaders in Calabria, alarmed at the possible environmental disaster, are protesting. Local mayors rallied in Rome on Tuesday to press the government to act quickly. Brussels has also added its voice. A letter sent last month by Stavros Dimas, European environment commissioner, seeking clarification from Italy, has so far gone unanswered.

The discovery of nuclear waste on the Cunski or other ships could raise uncomfortable issues for Silvio Berlusconi’s centre-right government, which is relaunching Italy’s nuclear power industry after a 22-year moratorium.

Now, the marine survey ship Mare Oceano is to use sonars to map and hopefully identify the ship, and test for radioactivity, before efforts are made to salvage the barrels. An Italian coastguard vessel has also searched for another wreck of a ship that Mr Fonti claims was scuttled off the central port of Livorno with toxic waste on board.

The Mafia’s involvement in illegal waste disposal on land, working for industrialists and local officials, is well documented.

The Mafia informant’s claims about involvement in sea dumping first made headlines in 2005, but progress was slow in pursuing them. Last month an expedition located what appears to be the Cunski, using Mr Fonti’s directions.

Over the years, magistrates have been aided by lists of suspicious sinkings provided by Lloyd’s of London in connection with suspect insurance claims, as well as persistent probing by environmental groups.

Francesco Neri, a Calabrian prosecutor who began investigating the “poison ships” mystery in the 1990s, says Mr Fonti has confirmed his suspicions.

“It was like investigating a murder without having the corpse,” he says, referring to their failure to pinpoint the missing ships, starting with the Rigel, which a court ruled was scuttled in 1987. Mr Neri recalls years of digging, threats, lack of funding and the strange death of his main investigator – one of several deaths said to be linked to the affair.

In December 1995, the investigator, Natale de Grazia, a young coastguard captain, died suddenly on a mission to the port of La Spezia. The official cause of death was heart attack, but colleagues suspect that he was poisoned.

Following the apparent find of the Cunski, a new inquiry has been launched by Calabria’s anti-Mafia directorate. (The exact identity of the ship is unclear – some disputed records show a ship named Cunski was scrapped years later.)

Attention is also being refocused on the case of a ship called Rosso which ran aground in rough weather near Amantea in Calabria in 1990, after what officials claimed was a botched attempt to scuttle it. Its cargo was removed and disposed of on land. Years later, doctors spotted a high incidence of local cancers.

Toxic contaminants and traces of radioactive caesium 137 were found in a nearby quarry used as an illegal dump. Investigating magistrates suspect a link with the Rosso.

Massimo Scalia, professor of physics at Rome’s La Sapienza university who led a parliamentary commission on illegal dumping in the 1990s, thinks the oceans were a natural extension for the Mafia.

“I’m sure they disposed of toxic and radioactive waste by sinking these ships,” he said. “But so far it is a theory – a theory in which I believe strongly but couldn’t find proof. That’s what I have been asking all these years: let’s find a ship and see what it carried.”

The commission and investigators repeatedly appealed for more government funding, but earlier inquiries were stopped.

Claims by Mr Fonti of involvement of Italian and foreign intelligence agencies and government officials in the trade of toxic and radioactive products have fuelled suspicions that some institutions may not have wanted to shed light on what lies on the seabed.

Investigators and parliamentarians have raised worrying questions about the source of the suspected nuclear material and who ordered its disposal.

In 2005, Mr Fonti told L’Espresso magazine that the Cunski carried radioactive waste from Norway. Ships, he said, were also sunk off Kenya, Somalia and west Africa. He also spoke of disposing waste for Italian, German, Swiss and Russian chemical and pharmaceutical companies.

Italian authorities have rejected his claim to have disposed of 40 lorry loads of material delivered to him at the Rotondella facility run by Enea, Italy’s nuclear authority.

Four years ago, Nicola Maria Pace, a prosecutor, told parliamentarians of three accidents involving nuclear waste stored at Rotondella, the last in 1994. He spoke of Italy’s “total submission” to US control over nuclear materials at Rotondella from 1954 to the 1970s, and how Iraqi scientists trained at Rotondella to use Italy’s Cirene reactors, which Iraq had sought to acquire in the 1980s.

In 2007, eight former senior Enea officials were placed under investigation over the handling of nuclear material. Italian media reported that the case was recently dropped.

More broadly, the extent to which a foreign hand is suspected is hard to gauge. Several sessions of the parliamentary waste commission were held in private for reasons of secrecy. Its public conclusions noted “interferences and threats” against investigators, and were critical of Enea’s management of nuclear waste.

The commission’s 1995 report spoke of the “possible existence of national and international trafficking in radioactive waste, managed by business and criminal lobbies, which are believed to operate also with the approval of institutional subjects belonging to countries and governments of the [European Union] and outside the EU”.

Prof Scalia is not alone in noting that Italy lacks a coherent nuclear waste policy and still has old waste held in “temporary” sites, some of it brought from the US decades ago.

The environment ministry and Enea did not respond to questions for this article. Statements by Stefania Prestigiacomo, the environment minister, have created confusion. First, the initial plans to use the ministry’s research vessel to survey the wreck was ditched. Then, parliament was told that a ship provided by Eni, the state-controlled energy group, was on its way from Cyprus.

Finally, the ministry said last Friday that the Mare Oceano, provided by Geolab, a Naples-based marine survey company, would do the work instead, directed by anti-Mafia investigators.

* This article was originally published in The Financial Times on 20 Octoboer 2009.