"Toxic ship-paint additive banned — after 40 years"

A treaty that forbids the maritime use of what the Environmental Protection Agency deems the most toxic chemical ever deliberately released into the world's waters is expected to be ratified within days.

It bans the poison tributyltin, a cheap and effective barnacle and algae killer once used on nearly all of the world's 30,000 commercial ships. The treaty also sets up a system for future testing and curbs on other hull biocides worldwide.

By 1995, more than 500 research papers worldwide had linked tributyltin, known as TBT, to adverse environmental or health effects. The most worrisome were "profound reproductive effects" coupled with diminished marine-species populations, according to Jill Bloom, an EPA chemical-review manager who worked on the treaty.

"It's very, very bad stuff," said Lindy Johnson, a National Oceanographic and Atmospheric Administration lawyer who worked alongside Bloom.

"It's a tremendous victory for the marine environment," said Simon Walmsley, the head of marine programs at the World Wildlife Fund's London office, "but one that is long overdue."

The ban on tributyltin signals a green-ward turn for the U.S. and European chemical and paint and coatings industries, which endorsed the deal, as well as cruise lines, freighter and container fleets, and shipyard and marina operators.

Their commitment will be tested further by other pending maritime environmental concerns, including, in California, growing resistance to copper-based substitutes for TBT. Other challenges include ballast water releases and stack emissions from ships' massive engines....

Major U.S. and European makers voluntarily stopped producing TBT in January 2001, and its presence in marine organisms is declining. But it continues to be widely used in much of Asia, and on ships built or overhauled there that ply the world's seas. Indeed, China only recently pledged to stop adding DDT, a far more infamous biocide, to its hull-protecting marine paints.

A year after the TBT treaty is ratified, neither the ships of ratifying countries nor foreign vessels that enter their waters will be allowed to have TBT on their hulls unless a sealant has rendered it inert. Ships found in violation will be put on an international blacklist and barred by other ratifying countries.

Whatever the treaty's signing date, the European Union is ahead of the game. It'll invoke the TBT ban and blacklist system, abetted by hefty fines, in January.

The tricky part of coming up with new protective coatings is killing growths on hulls without destroying other marine organisms, said Erik Norrie, the chief executive officer of New Nautical Coatings Inc. of Clearwater, Fla., the last U.S. producer of marine paint that contains TBT.

"It's like coming up with an antibiotic that doesn't kill germs," said Norrie, a maverick in the paint and coatings industry.

U.S. and European producers say they've pulled it off with copper-based substitutes and additives such as zinc parathion. They cost nearly double what TBT did, and shipyard operators debate whether they're as effective.

Norrie sells TBT-additive paints to offshore clients he won't identify. That's not illegal, according to the EPA, at least not until the United States signs the treaty....

That could happen under the International Maritime Organization treaty, the negotiation of which was a textbook case of self-interested compromise, several participants said. Environmentalists, who wanted a ban on all marine biocides, settled for action against TBT and a system for going after other harmful marine chemicals.

Paint companies that had used TBT found that they couldn't defend it. With help from additive makers such as Arch, they saw the virtues of a single international enforcement regimen over a welter of laws enforced by individual countries...