An article in the Scientific American suggests they are. Here's an excerpt.
Processing and safely storing waste from the chemical, pharmaceutical and other industries can cost hundreds, even thousands, of dollars per ton—which makes illegal disposal highly profitable. According to the Italian environmental organization Legambiente, some waste shippers that have operational bases in southern Italy have been using the Mediterranean as a dump. While acknowledging that “no wreck has yet been found that contains toxic or radioactive waste,” physicist Massimo Scalia of the University of Rome, La Sapienza, who has chaired two parliamentary commissions on illegal waste disposal, argues that other vidence makes their existence “beyond reasonable doubt.”
Scalia contends that 39 ships were wrecked under questionable circumstances between 1979 and 1995 alone; in every case, he adds, the crew abandoned the ship long before it sank. An average of two ships per year suspiciously disappeared in the Mediterranean during the 1980s and early 1990s, according to Legambiente—and the number has increased to nine wrecks per year since 1995. Paolo Gerbaudo of the Italian daily il Manifesto, who is assisting investigations, has identified 74 suspect wrecks of which he regards 20 as being extremely suspicious. (The record extends until 2001.)A chart of suspicious ship sinkings and disappearances in the Mediterranean Sea
(For a larger view and details of each sinking, click here)
. . .
Significantly, the increase in the frequency of wrecking correlates with the progressive tightening of international dumping regulations. The first suspect sinking, in 1979, occurred the year after the Barcelona Convention, which restricts the disposal of pollutants in the Mediterranean Sea, came into force. Over the following decades other treaties expanded the regulations, culminating in a 1993 amendment to the London Dumping Convention that halted the ocean disposal of all radioactive waste and in a 1995 amendment to the Basel Convention that banned the deposition of the industrial world’s lethal excreta in developing countries. The laws ruined the ambitious plans of one firm, Oceanic Disposal Management, incorporated in the British Virgin Islands, to drop tens of thousands of cubic meters of radioactive waste into the seabed off the African coast. Andreas Bernstorff, who formerly headed a Greenpeace campaign against the trade in toxic waste, reports that the number of schemes to ship such garbage to Africa fell steeply at this time, to at most one attempt per year. The drop coincides with a sudden and ominous rise in the frequency with which ships in the Mediterranean perished.
Despite profound concern in southern Italy, efforts to find the wrecks and identify their cargo have been slow. The endeavor is expensive, Scalia notes, and requires “serious engagement by magistrates and politicians”—which, but for “a few honorable exceptions,” has been lacking. Fear of violence may also have hindered investigation. In 1994 Italian television journalist Ilaria Alpi and cameraman Miran Hrovatin were shot dead near Mogadishu, after they picked up the hazardous waste trail in Somalia, where political upheaval has kept the country from enforcing controls.
That African nation possibly holds clues to the kinds of health hazards Italians might face. “My committee heard from Somalians who said many people in that area had symptoms of poisoning and some died,” Scalia attests, referring to a stretch of highway along which Alpi and Hrovatin may have witnessed the offloading of toxic substances. The tsunami of December 2004 dredged up giant metal containers from the seabed and placed them on Somali beaches—proving that the country’s coastal waters had also received questionable trash. A United Nations report blamed fumes from these unidentified objects for internal hemorrhages and deaths of local people.
In April 2007 Calabrian authorities had temporarily halted fishing in waters off Cetraro (where the Cunski lies, according to a turncoat from the ’Ndrangheta mafia) because of dangerous levels of heavy metals in marine sediment. In the region around Amantea, mortality from cancer between 1992 and 2001 exceeded that in neighboring areas, a study found; just as worrisome, hospitalizations for certain malignancies have risen in recent years.
There's more at the link.
The article makes for very interesting (and troubling) reading. If you think that here in the USA, we're not affected, think again . . . much of the world's toxic waste is generated here, and we're as vulnerable to criminally negligent disposal of it as any other country. Furthermore, if the countries bordering the Mediterranean find they can no longer use its water, gather its fish, or discharge their lower-grade pollutants into it because it's too toxic to absorb them any longer . . . just think of what that'll do to their economies - and those of their trading partners, like us.