Discrepancies in toxicity tests

I BP Report This is the activity report for the International Biological Programme Section on Marine Productivity (IBP-PM), Theme B, 'The effects of man's activities on the marine environment' from 1 October 1969 to 30 September 1970. Since the sixth meeting o f the Scientific Committee of the International Biological Programme (SCIBP), held in London on 1-3 October, 1969, IBP-Theme B has concentrated on contacting marine scientists in Latin America who are interested in problems concerned with the effects of man's activities on the marine environment. We have written to 332 scientists in Mexico and Central and South America as well as investigators working in t h e W est Indies and Cuba. We received forty-one replies from research scientists, students and administrators. In our original correspondence we asked for reports or brief descriptions o f current research activities which are appropriate for Theme B. The reports would be used to Ihcilitate further exchange in other regions of the world. Papers which were reasonably complete have been and will be published in the 'Marine Pollution Bulletin'. We are beginning to contact marine scientists working in Japan, the Philippines, and other parts o f the orient. Our objective again is to locate scientists who are interested in the effects of man's activities on the marine environment. Once we have determined those investigators who have a genuine interest in these problems we will solicit their participation in PM-Theme B. Participation in Theme B so far has consisted of (1) registering projects with the IBP, (2) submitting reports to the 'Marine Pollution Bulletin', (3) advising the coordinators of Theme B of existing research in this area and of changes in research programmes proposed earlier and (4) submitting papers to the conference on marine pollution held in Rome on 9-18 December, 1970, sponsored by the UN F o o d and Agriculture Organization (FAO). We will use our lists of marine scientists to augment the distribution and return o f completed scientific expert forms for FAO, Rome. Several delegations, including that from the Netherlands, have reported the results of Theme B activities. These reports were printed in the Progress Report, 1968-1969, of the Netherlands Committee for the IBP (Amsterdam, September 1970). Other Theme B activities were reported in the reports issued by various national IBP committees, Theme B will no longer be primarily concerned with pollution effects and physical alterations of the marine environment. We are now interested in documenting programmes concerned with habitat improvement and the fostering o f information exchange between investigators working in this area of research. Included, for example, would be programmes devoted to the development of artificial reefs and research concerned with the effects of mariculture on the marine environment. Finally we are interested in documenting the effects which the introduction of exotic species has had on the marine environment, We have printed and distributed an index to the first eighteen issues o f the 'Marine Pollution Bulletin'; this has been sent to 319 scientists of twenW-nine nations. This index is of value in locating scientists who are working on various investigations in marine pollution in several parts of the world. The proceedings o f the Second ThermalWorkshop were printed in 'Chesapeake Science', 10 (3-4) for September and December 1969. The workshop was supported by the US International Biological Program and was co-chaired by Joseph Mihursky and Jack B. Pearce. More than 200 participants from twenty-seven states and six countries took part in the thermal workshop. Although it was supported by US-IBP funds the thermal workshop was registered as a Theme B project. Copies o f the proceedings 182

can be obtained by writing to Martin Wiley, M a na c ng Editor, 'Chesapeake Science', Chesapeake Biological Laboratory, Solomons, Maryland, USA. The proceedings contain thirty-two papers on diverse subjects concerned with the effects of thermal pollution. Because of the obvious interrelationships between Theme B and Themes A (studies of comparative ecology in different climatic regions) and C (the cultivation of marine organisms) we propose a much closer working relationship between theme coordinators. Finally, it is essential that a higher level of US national support and recognition of Theme B be obtained. So far we have had relatively little success in obtaining US support for Theme B on the form of reports and projects registered as official IBP projects. If the IBP, as reported in news media, is to continue for an additional two years until 1974, it is not too late to encourage participation. Recently, many commercial firms have enquired about Theme B activities and requested the index. The major thrust and interest in environmental activity in the US seems to be moving from the academic-government centres to the private sectors. Sandy Hook Laboratory, Highlands, New Jersey 07732, USA.

J . B . Pearce L . A . Walford

Discrepancies in Toxicity Tests Two government agencies, one British the other Canadian, have recently published the results of toxicity tests. The Canadian report by Dr J o h n B. Sprague and Dr William G. Carson of the Biological Station at St Andrews, New Brunswick (Fisheries Research Board o f Canada, Technical Report No. 201) is concerned only with oil dispersants in connection with the Chedabucto Bay oil spill last February. The other report by Dr J. E. Portmann of the Fisheries Laboratory at Burnham-on-Crouch (Ministry of Agriculture, Fisheries and Food, Shellfish Information Leaflet, No. 19) deals with a wider range o f substances (one hundred and twenty in all) including oil dispersants, insecticides and some herbicides. The two reports illustrate the urgent need for some degree of standardization, or at least intercalibration, between toxicity tests in different parts of the world. At Burnham-on-Crouch a wide range of animals is used: two shrimps, Pandalus montagui and Crangon crangon, a crab, Carcinus maenas, two bivalves, Ostrea edulis and Cardiurn edule, a starfish, Asterias rubens and two fish, Agonus cataphractus and Pleuronectes sp. Not all of these are used routinely, and only Crangon has been used as a test organism for virtually all the substances examined. The Canadians have used young salmon, Salmo salar, 6-9 cm long routinely, occasionally supplemented by winter flounders, Pseudopleuronectes arnericanus, American lobsters, Homarus americanus, and soft-shelled clams Mya arenaria. Both groups measure LCs0 (lethal concentration for 50 per cent of the animals) but at Burnham the period of exposure is generally 48 h, at St Andrews 4 days as a rule. With these periods of exposure, the measurements are of acute toxicity, and Sprague and Carson warn that more prolonged exposure due to chronic pollution would be expected to have damaging effects in concentrations lower than those measured in these tests. The grades of toxicity that now seem to be gaining international acceptance are shown in the table on page 183. Of the dispersants tested by Sprague and Carson only 'Corexit 8666' achieved the grade o f ' p r a c t i c a l l y non-toxic' and to salmon, though not to flounders and lobsters, it

becomes 'moderately toxic' when mixed with 'bunker C' oil (itself 'practically non-toxic'),

Practically non-toxic

Slightly toxic Moderately toxic Toxic Very toxic

Grades of Toxicity acute toxicity threshold (LCs0) above 10,000 rag/1. (that is, parts per million) threshold 1,000-10,000 rag/1, threshold 100-1,000 mg/1. threshold 1-100 mg/1. threshold above 1 rag/1,

Portmann, on the other hand awarded the grade 'practically non-toxic to none of the substances he tested, but has several dispersants in the 'slightly toxic' range. These include 'DS 4545' in isoprophyl alcohol, 'Corexit 7664', new 'Dispersol OS' ('Dispersol SD'), 'BP 1100A' and 'BP 1100B'. The chief discrepancies concern 'Dispersol SD' which Sprague and Carson found to be 'toxic' or 'moderately toxic' to fish but not lobsters and 'BP l l 0 0 B ' which they f o u n d to be not appreciably better than the old toxic 'BP 1002'. Whether these differences are due to different sensitivities of test organisms, techniques, or duration of exposure in the British and Canadian tests is unknown but is now being studied by the laboratories. One difficulty in interpreting the Canadian results is that the principal tests were carried out on y o u n g salmon in freshwater and it is not certain whether they can be applied directly to a marine situation, 'BP 1100' is a fairly recent product which has gone through several formulations recently, so that it may be that different batches examined by the two laboratories were markedly different in their properties. Sprague and Carson certainly seemed surprised at its poor performance and t e s t e d s e v e r a l d i f f e r e n t b a t c h e s , Pesticides tested by Portmann were all at the other end of the range, and 'very toxic' indeed to arthropods, bivalves and fish.

DDT in Californian Coastal Waters California has recently strengthened the law on water quality control. Mr Kerry Mulligan, Chairman of the State Water Resources Control Board c o m m e n d e d the new measures in vigorous terms last July at the fifth meeting of the International Association on Water Pollution Research in San Francisco. But although the new law is designed to protect the quality of receiving waters, it has recently been learned that fishes in Santa Monica Bay, California, have higher concentrations of DDT and DDT residues than fish from any other waters in the continental United States (J. S. MacGregor, q u o t e d in the 'Los Angeles Times', 24 September, 1970). Even while this alarming discovery was being discussed, the Los Angeles Regional Board o f the State Water Resources Control Board had on its agenda the matter of the daily discharge of 150-250 kg of DDT and its metabolites into the ocean from the outfall o f the Los Angeles

County Sanitation District. It was brought to the attention of the regional board that it is reasonable to assume some connexion between the discharge of pesticides through the outfall and the extraordinarily high concentrations of DDT and DDT derivatives, which amount to 60-1,026 parts per million (p.p.m.), found in the livers o f fishes caught near the outfall. The Federal authorities recommend that no fish be sold in interstate commerce if they contain more than 5 p.p.m, of DDT and its metabolites. The muscle tissues of fishes from Santa Monica Bay contained up to 35 p.p.m, of DDT and residues. Because of this and the legal position that nothing may be discharged into the sea that might render the flesh of fish unacceptable for human consumption, a request was made that an order be issued to the sanitation district to 'cease and desist' from the discharge o f pesticides. In reply, the executive officer of the Los Angeles Regional Board, Mr Ray m o n d Hertel, suggested that a symposium be called to study this problem and the board decided to hold such a symposium 'some time in the next 6 months'. It is well known that DD'F has a broad range of adverse biological effects on non-target organisms. Although this group of toxins was rendering fish unfit for human consumption as well as causing general biological damage in the affected waters, the legally constituted bodies charged with protecting the quality of receiving waters have found no reason to act in abating the pollution of local inshore areas with excessive amounts of insecticides. During the discussion of this matter at the board meeting, it transpired that most of the poison discharged in the outfall was attributable to the local manufacture o f DDT and that it had been continuing at unknown, but presumably equivalent rotes for some time - possibly for years. Obviously, the future integrity and productivity of an inshore fishery is at stake in southern California, but so far no overt action has been taken by the regulatory agencies responsible for protecting the quality of inshore waters, nor is there any prospect of action at present. A weak statement by the State Department of Fish and Game that the department had not formulated receiving water standards for permissible concentrations o f pesticides did little to comfort the biologists who have considered this matter or seen the report on pesticide residues in fishes. Although it is evident that the direct discharge of these toxins in high concentrations into the ocean will lead to rapid assimilation by marine organisms, there seems to be no immediately enforcible legal action that can be taken to abate the pollution. Undoubtedly further studies of the problem will be of value, but it may not be the best course of action to await the result of these while pesticide residues continue to increase in marine organisms. The outlook is even more depressing at the international level. If local politics can prevent the abatement of a serious pollution problem, it is most improbable that we shall progress far in the vastly more complicated realm o f international politics. The prediction that we shall destroy our marine biological resources before we learn how to manage them properly, is only too likely to prove correct. Ocean Fish Protective Association Inc., 1417 Georgia Street, Les Angeles, California 90015, USA.

Rimmon C. Fay

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