An international convention banning the use of harmful organotin compounds in anti-fouling paints used on the hulls of ships and yachts will enter into force on Sept. 17. Organotin compounds are those based on tin with hydrocarbon substituents. The most often used is tributyltin (TBT).
Anti-fouling paints are used to coat the
bottoms of boat and ship vessels to prevent sea life such as algae and mollusks from
attaching themselves to the hull, which would slow the yacht and
increase fuel consumption.
Organotin compounds are very effective biocides. Unfortunately they are also very toxic to aquatic organisms such as mollusks (oysters, mussels, etc.) acting as endocrine disruptors.The convention:
The International Convention on the
Control of Harmful Anti-Fouling Systems on Ships (AFS Convention) was
adopted on Oct. 5, 2001 by the International Maritime Organization
(IMO) as well as the United Nations' specialized agency with
responsibility for safety and security of shipping and the prevention
of marine pollution by ships.
Under the terms of the Convention, it
enters into force 12 months after 25 states representing 25% of the
world's merchant shipping tonnage have ratified it. With the
ratification by the Republic of Panama in September, the AFS Convention
was ratified by 25 states, with a combined 38.11% of the world's
merchant shipping tonnage.
When the Convention is in force, ships and
yachts will no longer be permitted to apply or re-apply organotin
compounds, which act as biocides in their anti-fouling systems. Yachts
either shall not bear such compounds on their hulls or external parts
or surface or, for yachts already carrying such compounds on their
hulls, a coating that forms a barrier to such compounds will have to be
applied to prevent them escaping from the underlying non-compliant
anti-fouling systems. The Convention also establishes a mechanism to
evaluate and assess other anti-fouling systems and prevent the
potential future use of other harmful substances in these systems.
The Convention will apply to all yachts
flying the flag of a party to the Convention, as well as yachts not
entitled to fly their flag but that operate under their authority and
to all yachts that enter a port, shipyard or offshore terminal of a
In other words, either your flag of
registry will require compliance, or the port where the yacht calls
will require compliance by the September deadline.
For private and commercial yachts of 400
gross tons and above, an initial survey must be conducted by the flag
administration for issuance of the International Anti-Fouling Systems
Certificate (IAFSC). Any future changes or replacements after the
initial survey must be endorsed by the flag administration on the IAFSC.
For private and commercial yachts more
than 24 meters in length but less than 400 gross tons, owners have the
option of obtaining an IAFSC or self-declaring the type of anti-fouling
system used on the hull. This declaration must be supported by specific
documentation issued by the paint contractor.
EVISA Link Database: Toxicity of organotin compounds
EVISA Link Database: Environmental pollution by organotin compounds
EVISA Link Database: Industrial use of organotin compounds
The role of elemental speciation in legislation
EVISA Info: Regulation (EC) No 782/2003 of the European Parliament and of the
Council of 14 April 2003 on the prohibition of organotin compounds on
Related News EVISA News, April 30, 2008: Human exposure to organotin compounds via consumption of fish EVISA News, September 20, 2007: TBT-ban convention ratified
EVISA News, October 11, 2006: TBT from antifouling paint is still endangering marine life, says WWF ( 11.10.2006 )
EVISA News, January 23, 2004: Tuna is attuned to tin
EVISA News, December 15, 2003: Artifacts during the extraction of butyltin compounds from solid samples !
EVISA News, December 11, 2003: No degradation of TBT in seafood during cooking
last time modified: June 5, 2008