New dangerous chemicals in the environment: Lessons from TBT

M a r i n e P o l l u t i o n Bulletin

economic zone and intends to protect part of that zone as a special area by prescribing norms more stringent than those established through the competent international organization (in this case M A R P O L 73/78), it may designate a special area within the E E Z where more stringent measures may be applied according to art. 211(6) of the LOS Convention. As this provision is not an example of great draftsmanship, and there is hardly any state practice on this point, the conditions for invoking this article are not very clear. In any case IMO will have to be consulted, and there is a case for the view that cooperation with neighbouring states is required. An interesting development concerning the environmental hazards for marine protected areas caused by shipping takes place within IMO. Since 1986 the Marine Environment Protection Committee (MEPC) of IMO has been working on the issue of Particularly Sensitive Sea Areas, defined as areas which need special protection through action by IMO because of its significance for recognized ecological or socio-economic reasons and which may be vulnerable to damage by maritime activities.t These discussions, which will be continued at the 30th session of M E P C at the end of 1990, are intended to culminate in the adoption of guidelines for the designation of specially protected areas and the identification of particularly sensitive areas. These should assist IMO and national governments in identifying, designating, managing, and protecting particularly sensitive areas. As follows from the definition, special protective measures are limited to actions within the purview of IMO. These are essent D o c . M E P C 3 0 / 1 9 / 1 , p. 45, par. 4.1.3.

tially the same as those already mentioned: the development of routeing measures under SOLAS and the designation of special areas under M A R P O L . While the guidelines thus will not lead to any new legal possibilities, it is important that the problems of navigation and pollution in so far as they are regulated through IMO are taken together, and are supplemented with some guidelines as to the management of such areas. The shortcomings are also obvious however: other sources of pollution, such as pollution from off-shore installations or land-based sources, and other threats, such as fisheries and military activities, remain out of sight. It is thus obvious that the possibilities within these global instruments will have to be supplemented by international protective rules for the areas concerned at the regional level, such as those contained in the UNEP protocols mentioned above. After all, which protective measures are required depends on the threats to a particular area, and any international legal steps have to be tailored to those specific problems. While not all the regional instruments adopted up till now go equally far in prescribing international protecting obligations, it is notable that the more recent instruments such as the 1990 UNEP Protocol for the Wider Caribbean Region significantly go beyond earlier instruments such as the 1982 UNEP Protocol for the Mediterranean. This might, in combination with the other developments indicated above, be interpreted as a trend. It is clear however, that this trend should continue for some time however before an adequate international protection of marine areas will be attained. ANDRE NOLLKAEMPER

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Marine Pollution Bulletin, Volume 22, No. 1, pp. 8-10, 1991,

Printed in Great Brilain.

Viewpoint is a column which allows authors to express their own opinions about current events.

New Dangerous Chemicals in the Environment: Lessons from TBT D E R E K V. ELLIS

Derek Ellis is a Professor of Biology at the University of Victoria, Canada. He started biological indicator research related to TBT in 1987, and is now exploring new ways to bring the biology and chemistry together.

TBT (Tributyltin) was a new chemical in the sea during the early 1960s. It is no longer new, but it is now recognized as dangerous. The case has been well reviewed

many times (e.g. Stebbing, 1985; Hall & Pinkney, 1985; Thompson et al., 1986; Laughlin & Linden, 1987), and there are many features which contain lessons for the

Volume22/Number 1/January 1991 future. Particularly the TBT case is a well documented example of the problems in predicting environmental risks, assessing impact, and introducing control policies. To summarize TBT. It is a broad spectrum algicide, fungicide, insecticide and miticide long used in agriculture, especially by fruit growers. In the late 1960s it was introduced to the marine environment in boat antifoulant paints, and on salmon farm pen nets. However, it had the potential to reach the sea also through coastal run-off, and by leaching from plastic articles (due to its use as a stabilizer during their manufacture). Eventually, during the 1970s it was recognized as a cause of oyster farm losses, causing growth deformities and killing spat. The impact was recognized in other bivalve molluscs especially mussels. TBT was also found to bioaccumulate in salmon held i~nnet pens, and so to enter the human food chain. It is toxic to humans. The use of TBT has been banned in some countries during the past few years (mid-1980s), but often not completely. It is usually still permitted in anti-foulant paints on ships. Currently TBT is particularly liable to occur in wastewaters from marine paint-scraping yards. TBT is thus an example of slow detection, slow recognition, and slow and partial control of a dangerous chemical set free in the environment. There are two features of the case which I want to emphasize here as lessons for future responses to new toxins.

Biology and Chemistry It has only recently become possible to measure TBT accurately at the low concentrations (ppb) which are toxic. The techniques (there are now several--e.g. Short, 1987; Chapman & Samuel, 1988; Page, 1989) require expensive instruments and skilled operators, hence are rarely used for geographic-scale monitoring with many replicated samples. Fortunately there is a biological indicator which is cheap to measure, requires little instrumentation, only basic anatomical dissection and observational skills, and is quick. This is imposex. It is the imposition of male characters on females (Gibbs et al., 1987). The response has been experimentally induced by TBT bioassays (Bryan et al., 1988). The measurement technique has been refined to the extent that it is now applicable routinely to an easily collected, abundant, globally distributed type of organism: shoreline snails i.e. whelks and other forms of carnivorous Neogastropod molluscs (Ellis & Pattisina, 1990). Different coexisting species can respond differently (Bright & Ellis, in press). Being a simple, cheap, technique it can be widely applied. My low budget laboratory, using University of Victoria seed money, not government grants (no luck yet!), surveyed about 1000 km of coastline in two months of low tides during 1989 (Saavedra Alvarez & Ellis, 1990). The imposex biological indicator has been criticized for a number of reasons: e.g. genetic differences between populations, seasonal differences, possibility of other causes than TBT. One of my assistants (Campbell, 1990) has some answers to these, but some new criticisms of her own. She had access to genetic lineages

(frozen by R. Palmer, University of Alberta) unknowingly bioassayed 1983-89 in a marine laboratory flowthrough sea-water system, and was able to test retroactively some imposex measures for normality. Her results support imposex as an environmentally driven pathology, but indicate statistical problems in comparisons. Imposex has many qualities of good biological indicators. It provides a quick, low precision (hopefully not low accuracy) surrogate measure of an environmental parameter. Because it can be applied easily, it can be used to indicate where the more expensive and time-consuming direct chemical measures should be made for the suspected toxin. Biological indicators have great potential to assist in environmental protection. Any assessor of a new dangerous chemical, especially one that is expensive to measure, should consider the lessons of TBT and Neogastropod imposex, and give some effort to seeking a cheap, easily applied biological indicator test, as a guideline in assigning priorities for the more rigorous chemical analyses.

Control of Dangerous Chemicals The work in my laboratory on the TBT indicator has generated some interesting responses from senior pollution control scientists and administrators. I suspect that similar responses have occurred in similar contexts with other dangerous chemicals, and will recur with yet other toxins in the future. During the course of our surveys, I have often received expressions of disbelief that there was a problem from TBT in the individual's region of responsibility. In some countries this was in part lack of concern for economic and health consequences, where the nation's oyster or other bivalve mollusc fisheries or mariculture were small or remote. In other countries it was in part a consequence of controls having been introduced. There was no longer a problem! (And no more funds for research, nor to monitor the effectiveness of the controls, even though shown appropriate by Alzieu et al., 1986, 1989). Everywhere it was in part due to belief that a simple low-tech biological procedure could not be meaningful when compared to high-tech chemistry (which was often not being done since it was so expensive!). I submit that these kinds of responses by senior pollution control scientists and administrators are the reason for there being such a disgraceful 20-30 year lead-time in bringing in even partial controls for TBT, and in only a few countries. We have to do better than this with the new chemicals that are now being released to the environment. L e t us hope that the lessons from the TBT case will be learnt by all of us who are concerned about the problem of new chemicals: scientists who have the opportunity to research quick assessment procedures, and administrators who can fund region-wide low technology indicator surveys, so that more expensive and rigorous assessments can then be made in the right places.

Marine Pollution Bulletin Alzieu, C. L., Sanjuan, J., Deltreil, J. P. & Borel, M. (1986). Tin contamination in Arcachon Bay: Effects on oyster shell anomalies. Mar. Pollut. Bull. 17,494-498. Alzieu, C. L., Sanjuan, J., Michel, P., Borel, M. & Dreno, J. P. (1989). Monitoring and assessment of butyltins in Atlantic coastal waters. Mar. Pollut. Bull. 20, 22-26. Bright, D. & Ellis, D. V. (1990). A comparative survey of imposex in NE Pacific Neogastropods (Prosobranchia) related to tributyltin contamination and choice of a suitable bioindicator. Can. Journ. Zool. (in press). Bryan, G. W., Gibbs, P. E. & Burt, G. R. (1987). A comparison of the effectiveness of tri-n-butyltin chloride and five other organotin compounds in promoting the development of imposex in the dogwhelk, Nucella lapillus. Z Mar. Biol. Ass. UK 68,733-744. Campbell, E. (1990). Critical appraisal of neogastropod imposex as a biological indicator of tri-butyltin contamination. B.Sc. Hons. Thesis, University of Victoria/Queen's University. Chapman, A. H. & Samuel, A. (1988). A simplified procedure for the determination of butyltin species in water. Applied Organomet. Chem. 2, 73--77. Ellis, D. V. & Pattisina, L. A. (1990). Widespread neogastropod imposex: a biological indicator of global TBT contamination. Mar. Pollut. Biol. 21,248-253.

MarinePollutionBulletin,Volume22, No. 1,pp. 10-14, 1991. Printedin GreatBritain.

Gibbs, P. E., Bryan, G. W., Pascoe, P. L. & Burt, G. R. (1987). The use of the dog-whelk, Nucella lapillus, as an indicator of tributyltin (TBT) contamination. J. Mar. Biol. Ass. UK 67,507-523. Hall, L. W. Jr. & Pinkney, A. E. (1985). Acute and sublethal effects of organotin compounds on aquatic biota: an interpretive literature evaluation. CRC Crit. .Rev. Tox. 14, 150-209. Laughlin, R. B. Jr. & Linden, O. (1987). Tributyltin--contemporary environmental issues. Ambio 16,252-256. Page, D. S. (1989). An analytical method for butyltin species in shellfish. Mar. Pollut. Bull. 20, 129-133. Saavedra Alvarez, M. M. & Ellis, D. V. (1990). Widespread neogastropod imposex in the northeast Pacific: implications for TBT contamination surveys. Mar. Pollut. Bull. 21,244-247. Short, J. W. (1987). Measuring Tri-n-Butyltin in salmon b y Atomic Absorption: analysis with and without gas chromatography. Bull, Environ. Contain. Toxic. 39, 412-426. Stebbing, A. R. D. (1985). Organotins and water quality--some lessons to be learned. Mar. Pollut. Biol. 16,383-390. Thompson, J. A. J., Sheffer, M. G., Pierce, R. C., Chau, Y. K., Cooney, J. J., Cullen, W. R. & Maguire, R. J. (1985). Organotin Compounds in the Aquatic Environment." Scientific Criteria for Assessing Their Effects on Environmental Quality. National Research Council of Canada, Environment Secretariat, Publ. No. NRCC 22494.

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Heavy Metals in Mussels and Fish from Italian Coastal Waters ROSA GIORDANO*:[:, PAOLO ARATAt, LAURA CIARALLI*, SILVANA RINALDI*, MICHELE GIANIt, ANNA MARIA CICEROt and SERGIO COSTANTINI* *Istituto Superiore di Sanitd, Applied Toxicology Laboratory, Viale Regina Elena, 299, 00161 Rome; t lstituto Centrale per la Ricerca Scientifica e Tecnologica Applicata alia Pesca Marittima, Via Lorenzo Respighi, 5, O0197 Rome, Italy ~;To whom correspondence should be addressed.

Concentrations of mercury, cadmium and lead were determined in the soft tissue of four types of marine organisms (Mytilus gailoprovincialis Lmk., Murex trunculus, Serranus scriba and Sertorius cabrilla), collected along the Italian coasts from Genoa (Ligurian Sea) to Termoli (Adriatic Sea) in the summer of 1986. T h e analyses were performed by the electrothermal (cadmium and lead) and cold vapour (mercury) atomic absorption techniques. Levels of metals in Mytilus gaUoprovincialis were for the most part low, except at a few sites. M u m trunculus contained higher mean concentrations of mercury and cadmium and lower concentrations of lead. In Serranus scriba and Serranus cabrilla, mean levels of mercury were 3 1 6 + 1 5 4 and 1 8 1 + 8 6 og l-t fresh weight, respectively, and the levels of cadmium and lead were generally below the detection limits calculated for both these elements.

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The role heavy metals play as pollutants is widely recognized (Ballester et al., 1980; Chester, 1975; Ober et al., 1987). In the sea, pollutants are potentially accumulated in marine organisms and sediments, and subsequently transferred to man through the food chain. Of all the studies carried out up to now on the subject of heavy metals in the Mediterranean area, only a few have been specifically dedicated to the Italian Sea, sometimes restricted to limited zones (Castagna et al., 1985; Leonzio et al., 1981; Renzoni et aL, 1986), and involving the study of mercury pollution. The purpose of this study was to evaluate the presence of some heavy metals chosen among those with the highest pollution potential (FAO, 1976), namely mercury, cadmium and lead, in marine benthic organisms collected along the Italian coasts. The sampling was performed by the WWF (World Wide Fund for Nature) as part of the 'The sea must live'