Potential pollution of a marine environment by lead alkyls: the Cavtat

Potential pollution of a marine environment by lead alkyls: the Cavtat incident. Giovanni Tiravanti, and Gianfranco Boari. Environ. Sci. Technol. , 19...
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Literature Cited (1) Armstrong, D. E., Anderson, M. A., Perry, J. R., Flatness, D.,

“Availability of Pollutants Associated with Access to the Great Lakes”, unpublished EPA Progress Report, University of Wisconsin-Madison, 1977. (2) Logan, T. J.,“Chemical Extraction as an Index of Bioavailability of Phosphate in Lake Erie Basin Suspended Sediments”, Final Report for US. Army Corps of Engineers, Buffalo. (3) U S . Environmental Protection Agency, “Algal Assay Procedure Bottle Test”, National Eutrophication Research Program, Corvallis, Ore., 1971, 82 pp. (4) Cowen, W. F., Lee, G. F., Water Pollut. Control Fed., 48,580-91 (1976). (5) Cowen, W. F., Lee, G. F., Sirisinh,K., Water Pollut Control Fed., 48,339-45 (1976). (6) Cowen. W. F.. Lee. G. F.. ‘‘Algal Nutrient Availabilitv and Limitation in Lake Ontario During YFYGL”, EPA-600/3-76-b94a,EPA, Duluth, Minn., 1976. (7) Dorich, R. A., Nelson, D. W., “Algal Availability of Soluble and Sediment Phosphorus in Drainage Water of the Black Creek Watershed”, Indiana Experiment Station, Purdue University, West Lafayette, Ind., 1977. (8) Lake, J., Morrison, J., “Environmental Impact of Land Use on Water Quality”, EPA-905/9-77-007-B, Great Lakes National

Program Office, EPA, Chicago, Ill., 1977. (9) Golterman, H. L., Bakels, C. C., Jacobs-Mogelin, J., Verh. Int. Ver. Theor. Angew. Limnol., 17,467-79 (1969). (10) DePinto, J. V., Verhoff, F. H., Enuiron. Sci. Technol., 11,371-7 (1977). (11) U.S. Army Corps of Engineers, Buffalo District, “Lake Erie Wastewater Management Study Preliminary Feasibility Report”, Buffalo, N.Y., Dec 1975. ( 1 2 ) Logan, T. J., Verhoff, F. H., DePinto, J. V., “Bioavailability of Phosphate in Suspended Stream Sediments from Tributaries into Lake Erie”, Technical Report, US. Army Corps of Engineers, Buffalo, N.Y., Sept 1978. (13) McKosky, F., M.S. Thesis, Clarkson College of Technology, 1977. (14) Bierman, W. J., Jr., private communication, US. EPA Gross Ile Laboratory, 1978. (15) “Standard Methods for the Examination of Water and Wastewater”, 14th ed., American Public Health Association, New York, 1975. Received for reuiew December 7,1978. Accepted March 14, 1979. This work was supported entirely by the U.S. Army Corps of Engineers, Buffalo District. Some of this material was presented at the International Association of Great Lake Research Conference in Windsor. Ontario, M a y 1978.

Potential Pollution of a Marine Environment by Lead Alkyls: The Cavtat Incident Giovanni Tiravanti” and Gianfranco Boari lstituto di Ricerca sulle Acque, CNR, Via F. De Blasio, Bari, Italy

T h e 2000-ton Yugoslav cargo ship Cavtat, containing about 325 tons of lead alkyl antiknock compounds, sank on July 14, 1974, in 94 m of water, 3.5 miles southeast of the Otranto Cape, in t h e Adriatic Sea. T h e organic nature of this load gave rise t o pollution problems that had not yet been considered in the literature. A significant release of lead alkyls was prevented by salvaging the material, with a loss of only 7%. A preliminary evaluation of t h e potential polluting effects of lead alkyl dispersion in t h e marine environment is reported, solid evaluation being‘ based on a diffusion/convection transport model which allows t h e compound hypothetical concentration distribution in the wreck area t o be calculated. Analysis of seawater, sediments, and biological samples near the wreck, using standard analytical methods, verified t h a t there was little environmental effect.

alkyl load. I n fact, an international scientific meeting ( 3 )revealed a serious lack of knowledge concerning t h e long-term effects lead alkyls might have in seawater. Evaluation of the pollution effects is only possible knowing: t h e concentrations and amounts of lead alkyls in seawater, their degradation kinetics, a n d their staying power in the environment; t h e possible interactions with aquatic biota and sediments. Scientific studies related to these problems are very scarce. The existing data about lead alkyl effects on ecosystems and the hypothetical concentration distribution of the compound in the wreck area, which was worked out by means of a mathematical model, are reported in t h e following sections of this paper. Preliminary analytical data on lead contents in seawater, sediments, and biological samples collected near the wreck are also reported.

Fortunately, very few shipping accidents involving considerable amounts of lead alkyl antiknock compounds have occurred until now (1974 world production: 3 X lo5 tons of Pb/year ( I ) ) . T h e first accident t h a t did occur was in the Gulf of Trinidad in November 1961; t h e second was off Green Point, a few kilometers out of Cape Town Harbour, South Africa on July 1,1966 (2). In both cases, no studies to ascertain possible damage to the marine environment were recorded in t h e literature. T h e Cavtat wrecked on July 14, 1974, :1.5 miles southeast of t h e Otranto Cape, in the Adriatic Sea, and sank to a depth of 94 m a t 40’03’02” N, 18’34’02’’ E. (See Figure 1 for a map of t h e accident area.) Included in the cargo were 900 drums containing a total of about 325 tons of tetramethyllead (TML) a n d tetraethyllead (TEL) antiknock compounds, manufactured by the Associated Octel Co., Ltd. of London. The Cavtat wreck was immediately recognized as a formidable threat to t h e marine environment due to the completely unfamiliar pollution problems related to t h e organic nature of the lead

Literature Review

0013-936X/79/0913-0849$01.00/0 @

Various aspects of inorganic lead chemistry and toxicity have been described in the literature, and scientists from different disciplines have become concerned about the everincreasing levels of lead in the environment. Seawater pollution is generally related to inorganic and particulate aerosols from gasoline antiknock compounds, domestic sewage effluents, or some high-temperature industrial processes (pit-coal combustion, cement production, etc.) ( I 1. Recently, Huntzincker e t al. ( 4 ) carried out a study concerning the leaded gasoline consumption in the Los Angeles area and, with the aid of a mathematical model, concluded t h a t 20-25% of produced aerosols find their way into t h e oceans. This phenomenon is even more remarkable in t h e more industrialized northern hemisphere. T h e lead concentration in deep seawater is considered to be in the region of 0.001 FgIL ( 5 ) ,while t h e lead concentration in near surface a n d polluted coastal waters may go u p more than 100 times t h a t amount.

1979 American Chemical Society

Volume 13, Number 7 , July 1979 849

Figure 1. Map of

the Cavtat accident area. (+) Position of t h e wreck

In the absence of any reliable data on equilibrium constants between lead and various other organic and inorganic ligands, it was suggested (6) that these very low concentrations might quite possibly depend on the low solubility of the inorganic lead salts in waters having a p H of about 8. Hence, although the inorganic lead fluxes in oceans around the world are considerable, most of them are removed from waters very quickly and become incorporated in the sediments in harmless forms. A different approach to the impact lead alkyls have on sea850

Environmental Science & Technology

water must be considered. Due to lead’s very rapid degradation kinetics on going from organic to inorganic forms during the process of internal combustion, environmental lead alkyl pollution can be said to be caused only by accidental releases into water, as was the case for the Cavtat. Generally speaking, the most important aspects of marine pollution are the possible damage to marine organisms and the danger to humans from consumption of contaminated fish. Some data exist on the effects inorganic lead has on marine

organisms (7-10). Recent studies (11, 12) have shown that lead is bioaccuniulated with respect to calcium going from seawater to kelp, while it is biodiminished when going from kelp to the gastropod food chain, with an overall lead pollution factor for tuna muscle of lo4, thereby giving rise to contaminated seafood. Indeed, little is known on how lead alkyl affects ecosystems. Some data are relative to T M L effects on algae in freshwater (23),where a T M L quantity lower than 500 pg induces an 85% drop in primary activity and a 32% drop in cellular growth of Scenedesmus quadricauda and Anhistrodemus falcatus. Similar effects are produced with 20 times as much lead in the form of lead nitrate (13).The acute toxicity to rainbow trout (Salmo gairdneri) was investigated ( 2 4 ) in batch experiments with triethyl- and trimethyllead chloride in river waters. The results, extrapolated over a period of 3 months, indicate safe concentrations in the water to be 750 and 1300 pg of P b L for (CZHj)3PbCl an'd (CH:3)3PbCl, respectively. Other data refer to acute toxic effects on bluegill sunfish (Lepomis macrochirus) in fresh water: for TEL solutions, LCso values after 24 and 48 h are, respectively, 2000 and 1400 pg of Pb/L (15). Bioassays on the acute toxicity of alkyls in seawater, recently performed a t the IRSA-CNR Laboratory of Brugherio (Milan) (16) give the following data for the LCjo after 48 h: pg of

Pb/L

test organism

TML-CB

TEL-CB

hacteria algae crustaceans fish

1900 1650 250 100

200 150 85 65

These data show t h a t T E L is much more toxic than TML. However, uptake of heavy metals directly by marine organisms from seawater is not the only route of contamination: most pollutants are also absorbed from food or sediments ( I 7-19). Patterson (20) showed that only soluble lead interacts with biological activity and is accumulated by aquatic organisms. Assuming the same accumulation factors for the alkyls as for inorganic lead in phytoplankton, found to be on the order of 102-104 (21), and considering the former's greater solubility (see Appendix), the higher trophic levels could be polluted either hy lead alkyls in seawater or by their leaded food sources. I t should be noted that phytoplankton along Italian seacoasts make up 95% of the total marine biomass (22). For humans, acute and chronic conditions due to ingestion, vapor inhalation, or skin adsorption of lead alkyls are well known medically because of long and varied experiences suffered by the workers in factories producing these compounds (23-25). Gremer (26-28) found that liver enzymes can convert the tetraalkyl compounds into their trialkyl salts, which are far more reactive and toxic for mammals. Very little is known about the biochemical mechanisms that affect the central nervous system and change cell morphology as a result of lead poisoning. However, it is interesting to note that after acute poisoning an apparently complete recovery ensues when mammals are moved away from the polluting source (in the case of inhalation) or when they survive the dosage (in the case of ingestion) (29). Here, too, T E L toxicity is higher than that of T M L (29), though the threshold limit values (TLV) for TML and TEL are equal to 0.075 rng/m" of air ( 3 0 ) .This corresponds to a 1-mg alkyl inhalation per day by a man weighing 70 kg. No data are available about the safety maxima for direct ingestion of compounds. FAO/WHO report no. 51 (1973) gives a safe value of 3 mg/week for overall lead intake, coming from all inputs, especially from food (31 1. This limit would probably not be

"safe" in the case of lead alkyl polluted seafood ingestion but should be lowered as was done for organomercury compounds (11.

Results a n d Discussion

A preliminary evaluation of the potential polluting effects of lead alkyl dispersion in the marine environment was carried out making use of: (a) a diffusionlconvection transport model; (b) monitoring of lead content in seawater, sediments, and biological organisms within the wreck area. The lead-alkyl mixture density was found to be about 1.6 g/cm3. Consequently, if there was any leakage, the compounds loaded on the deck and in the hold would have sunk to the bottom of the sea, where they would have formed a body which could either have been adsorbed by the sediments or slowly solubilized by seawater. Stream velocity along the Otranto Channel sea bottom is on the order of 0.1-0.18 m/s, with a maximum value of 0.6 m/s (32), which is too low to drag the body (33). Preliminary and qualitative experiments have shown t h a t the antiknock compounds only enter the superficial layers (5-10 cm) of Otranto sediment, mainly composed of clays, calcite, quartz, and feldspar (34). Calculated Dispersion of Lead Compounds f r o m t h e Wreck. Many theoretical and experimental papers in the literature deal with waste disposal in deep waters, but most of them refer to streams coming from estuaries or sewers and wastewater pipes. Very little, indeed, is known about the diffusion of negligible mass pollution loads on the sea bed 100 m down. In order to obtain more information on the matter, a mathematical model for the dispersion of lead compounds was worked out using the classical diffusion equation in flow conditions. The Otranto Channel was considered to be a rectangular cross-section duct, 100 m deep and 100 km wide, with side walls, sea bottom, and water-air interface impermeable to lead. The polluting source was located 5 km off the Italian coast; the stream velocity was assumed to be constant, equal to 0.25 m/s (35) and flowing southward parallel to the coast, as, in fact, does the prevailing bottom stream in the wreck area (32). Interactions between lead alkyl compounds and seawater, sediment, and aquatic life were assumed to be negligible. Assuming isotropic diffusion coefficients equal to 0.1 m2/s (36), the diffusion equation was solved analytically considering a point source and a quasicontinuous polluting flow

Figure 2. Computed lead alkyl concentrations on seawater surface (curves c, d) and along the sea bottom (curves a, b) as a function of the source distance downflow. Lead release flow: 100 kg of Pb/h. Continuous lines: numerical solution; dotted lines: analytical solution

Volume 13, Number 7, July 1979

851

Table 1. Analytical Data for Total Lead Contents Obtained from Seawater Samples and Sediments Collected June 19, 1976 Near the Cavtat Wreck position

1 MS 2 3 4

1 miles over the wreck 0.25 mile N 0.25 mile E 0.25 mile S 0.25 mile W 0.25 mile SW 0.25 mile NW 0.25 mile NE superficial fraction 12 mile N superficial fraction close to the wreck

5 6 7 8 9 10 11 a

surface water, pg of Pb/L

sample

Data from lstituto di Ricerca sulle Acque, Bari.

a

b

a

5.5 5.0 14.0 2.0

8.0 11.0 13.0 15.0 13.0 6.0 10.0 8.0 15.0

5.0 5.0

5.5 2.0 7.0 5.0

5.5

Environmental Science & Technology

5.5 5.0 13.0 10.0 7.5 6.5

b

a

6.0 12.0 4.0 7.0 9.0 11.0 6.0 7.0 1.o

9.0 4.0 9.0 1 .o 5.0 1.0 7.5 0.0 9.0

b

9.0 7.0 2.0 1.o 15.0 11.0 6.0 13.0 7.0

marine sediments, pg of Pb/g dry wt a b

8.8 8.6 5.6 4.3 7.3 8.5 5.1 4.0 9.0 28.7 24.4

8.5 6.4 12.2 10.7 9.8 7.4 7.3 9.6 5.9 30.5 58.1

Data from lstituto Superiore Sanita, Rome.

consisting of a number of instantaneous releases of a fixed quantity of lead ( 3 4 ) . T h e total concentration a t any given time and location was computed as the sum of n concentrations corresponding to n releases. The diffusion equation was also solved numerically by t h e finite differences method, considering a continuous and constant source of pollution, 40 m long and 1 m high, located in the vertical plane perpendicular t o the coast. Figure 2 shows the pattern of computed lead alkyl concentrations as a function of distance downstream of the source in steady-state conditions a t 0 and 94 m depth, along the vertical plane comprising the source and parallel to the stream direction. The continuous line refers to the numerical solution; t h e dotted line refers to t h e analytical one. In both cases, a safety factor as high as a release flow equal t o 100 kg/h of lead alkyl in solution was assumed corresponding to the breakage of 1drum every 90 min. From Figure 2 it can be seen t h a t concentrations computed assuming different source characteristics agree very well about 1 km downflow of the wreck, where magnitude is rather low, in the region of about 10 pg of Pb/L. It is interesting to note that, while t h e lead concentration on the bottom is a monotonic decreasing function, the surface concentration reaches a maximum approximately a t the point where complete merging concentration of the 94-m layer occurs. The concentration of lead alkyl which could, in theory, have reached the Italian coast 5 km downflow from the wreck was analytically evaluated as negligible, much lower, in fact, than in “nonpolluted” seawaters. Analytical Data. Lead alkyl analysis of seawater samples collected near the wreck gives a n indication of the release of the compounds from the Cavtat wreck. Considering that lead alkyl solubilities are significant and hydrolysis effects would increase solubility (see Appendix), it can be expected that, if a major release occurs, it should be detectable by standard analytical methods, with a concentration threshold of 10 pg/L, even if contamination during seawater sample manipulation can considerably affect analytical results (37, 38). However, due to a scarcity of analytical procedures regarding lead alkyl determination in seawater, the main purpose for analysis was t o detect any eventual massive seawater pollution. A few days after the Cavtat accident, a first set of marine sediments and seawater samples was collected a t 0, 50, and 90 m of depth within a 300-m radius from the wreck. The total lead conFent was analyzed by atomic absorption spectropho; tometry, after predigestion with nitric acid, using the typical solvent extraction system with methyl isobutyl ketone 852

90 m deep water, pg of Pb/L

50 m deep water, pg of Pb/L

( M I B K ) a n d ammonium pyrrolidine-dithiocarbamate (APDC) (39). Results were below the sensitivity limits of the method used in all the seawater samples and revealed 1-4 mg of Pb/kg dry weight in the sediments. The latter values are consistent with average P b contents in sediments with the same mineralogical composition (40). A second study was carried out 1 year later and a third collection of samples was made on October 28, 1975, during a Yugoslav submarine survey of the wreck (41).Similar results were obtained. Further investigations on seawater, sediments, and biological organisms collected near the wreck were carried out in J u n e 1976. Fish samples were also collected 12 miles upstream for comparison ( 3 4 ) .T h e same samples were also analyzed by Cotta Ramusino, of t h e Istituto Superiore di Saniti (ISS) of Rome, using different techniques, such as anodic stripping voltammetry and, for the fish samples, X-ray emission spectroscopy. Tables I and I1 report the preliminary analytical results for seawater, sediments, and biological organisms obtained from the various laboratories involved with t h e fourth sampling cruise. The obtained results indicate that total lead concentrations in the seawater were below 10 pg/L. It is worth noting that the accepted “minimum risk concentration” for lead on marine organisms is considered to be 10 pg of Pb/L (22). Total lead concentrations in marine sediments (5-30 mg/kg dry weight) indicate that the sea bed bottom was not heavily polluted. The total lead contents in fish analyses performed a t the Istituto di Ricerca sulle Acque (IRSA) and a t the Istituto Superiore di SanitA (ISS) were generally found to agree only for those samples collected 12 miles from the wreck, in a northerly direction. For the benthic organisms taken near the wreck, the IRSA lead values are for the most part five times higher than the ISS values. This difference can be ascribed to the different handling of the samples: all fish analyses were carried out on the whole body, plus skin, for the IRSA tests, and only on the tissue for the ISS. The results hence indicate that the benthic organisms near the wreck were slightly polluted by lead. No pollution was observed in pelagic organisms. After a long disputed controversy, the drum recovery began in March 1977, before any breakup had occurred. Special submarine procedures were applied in order to safeguard the divers’ health and to prevent environmental pollution. Drum recovery was completed in April 1978, no harm having come either to divers or the environment. Seven percent of the

Table II. Total Lead Concentrations, Expressed as Micrograms of Lead per Gram Fresh Weight, in Marine Organisms Collected June 19, 1976 in the Cavtat Area organism

bogue (Boops boops) whole liver brain hake (Merluccius merluccius) whole liver brain striped mullet (Mullus barbatus) whole liver brain weever (Trachinus spp.) liver kidney brain ray (Raja) liver scorpion fish (Scorpaena spp.) angler fish (Lofius spp.) kidney brain large-scaled scorpion fish (Scorpaena scrofa) sole (Solea lutea) common sole (Solea solea) small spotted dogfish (Scyliorhinus caniculus) muscle brain cuttlefish (Sepia officinalis) (anguilliformes) octopus (Octopus vulgaris) (Gadidae) crustaceans (Crustacea) (Gastropoda) starfish (Echinodermata as teroidea) a

-

12 miles N of the wreck

close to the wreck

b

a

a

b

0.1

0.12

0.60

0.25 0.215

0.75

0.10 0.09 0.10 0.14 0.21

0.1-0.17 0.4 0.15 0.1 0.08 0.03

0.41 0.33

0.10

0.43 0.68 0.16 0.32

0.1

0.22-0.4

0.1 0.16 0.17

0.03 0.04 0.2-0.4 0.09 0.74

0.10

0.17 0.06-0.26

1.10 0.40

0.18 0.14

0.90

0.18 0.06

o.1e 0.07 0.03

0.14 0.18 0.9 0.15 0.20

0.04

Data from lstituto di Ricerca Sulle Acque, Bari. Data from lstituto Superiore Sanita, Rome

products were found missing, probably lost as an immediate result of the collision. Results from a n oceanographic survey performed during drum recovery are still under study. Conclusions Assuming a high release velocity of 100 kg of Pb/h, computed lead concentrations at the Italian coast line were found to be negligible. 'This means that there were no hazards at all to swimmers. Concentrations found in seawater samples collected close to the wreck were below 10 pg of Pb/L, and they are probably in excess of true values, due to contamination factors. Analytical data for sediment and organism samples indicate low quantity lead alkyl leakages over a limited area very close to the wreck. These experimental results verify that a loss of 7% of the cargo, immediately after t h e accident, was not enough to produce major environmental effects. In this case, the assumption that the local fishermen could be considered safe, if the FAO-recommended limit for organolead concentrations were taken as valid (311, is also justified. More study of aqueous behavior of lead alkyls is urgently needed to develop better strategies for environmental protection, in similar cases. The fact is that present knowledge of lead alkyl behavior in seawater environments. especially

their long-term effects, does not allow any foresight into whether a considerable amount of these compounds could, in fact, damage marine ecosystems, for the following reasons: (a) the analytical determination of lead alkyl compounds in seawater is quite difficult even when concentrations are greater than those of natural inorganic lead; (b) these compounds are not readily degraded chemically into inorganic lead and they can persist for a certain length of time in the environment; (c) they might easily be accumulated in the first trophic level, Le., in phytoplankton and macrophytes; lead alkyl release velocities are not known; ( d ) trialkyl salts may be better metabolized by fish. If organic lead is incorporated into aquatic soft tissues, i t may be recirculated upon death, and then be assimilated by humans, especially by fish-eating fishermen and their families. This incident has been brought to a most successful ending. I t evidenced, however, the need to understand what toxic chemicals are being moved across t h e oceans and what types of accidents we should he prepared to cope with.

Acknou~ledgment The authors are grateful to Dr. A. Maritati (Judge of Otranto Court) for permission to publish some confidential data reported in a judicial report. Volume 13, Number 7, July 1979

853

Appendix Lead Alkyl Properties. From the basic properties and the details of the electronic structure, it was shown t h a t lead compounds contain highly polar bonds, which facilitate attack by polar reagents ( 4 2 ) .In addition, lead compound reactivity is enhanced by the presence of vacant d orbitals, making the formation of stable transition states possible. The solubility of T E L in distilled water, as determined by Feldhake and Stevens in 1963, lies between 0.2 and 0.3 mg of Pb/L ( 4 3 ) . No data are reported in the literature for T M L solubility in water; the Octel data give a value of 9.0 mg of Pb/L (2). As far as water contamination is concerned, however, hydrolysis is important, since trialkyl salts are also toxic and their solubility is very high. The degradation of tetraalkylto trialkyllead compounds in aqueous solution follows a first-order reaction initially. Only a few data concerning the evaluation of the first kinetic constant K1 in dilute seawater are available (2): TEL

K1 = 1.33 X 10-5

S-1

TML

K1 = 1.83 X

s - ~

Very little is known about the degradation reactions leading to complete replacement of the alkyl groups via dialkyl compounds. Octel data indicate t h a t trialkyl ions are very stable in aqueous solution, and the degradation of dialkyl compounds t o inorganic lead is relatively rapid ( 2 ) . In the Cavtat situation, the lead alkyl compounds interact with aquatic biota and with sediments as well. Hence, the knowledge of biological and sediment lead transport pathways a n d of degradation kinetics is necessary for a more accurate estimate of lead alkyl compound concentrations in seawater. Literature Cited (1) Goldberg, E. D., “The Health of the Oceans”, The Unesco Press, Paris, 1976, Chapters 2 and 5 . (2) “Octel Report after Diver’s Submarine Survey”, London, J a n 30, 1976.

( 3 ) Report of the NATO Science Committee’s Panel on Marine Sciences on the Recommended Strategies in the Cavtat Episode, Venice, Aug 30-31,1976. ( 4 ) Huntzinker, J. J., Friedlander, S.K., Davidson, C. I., Enuiron. Sei. Technol , 9,448-57 (1975). (5) Patterson, C., Settle, D. M., Natl. Bur. Stand. (U.S.)Spec. Publ., No. 422,321-51 (1976). (6) Hem, J. D., Durum, W. H., J. Am. Water Works Assoc., 65,562-8 (1973).

(7) Reish. D. .J.. Kauwline. T . tJ.. Mearns. A. J.. J Water Pollut. C‘ontroiFed., 47, 1617-3k (197i). (8)D’Amelio, V., Rec. Int. Oceanogr. M e d . , 33, 111 (1974).

J. S., “Pollution and Physiology of Marine Organisms”, Academic Press, New York, 1974, pp 465-85. (10) Gray. J . S.. Ventilla. R. J.. Ambio. 2i4). 118 (1973). (1 1) Ella;, R., Hirao, Y., Patterson, C., International Conference on Heavy Metals in the Environment. Toronto. Oct 30, 1975. ( 1 % ) Patterson, C.. Settle, D.. S h a d e , B., Burnett, M., in “Marine Pollutant Transfer”, Windom, H. L., Duce, R. A,, Eds., Lexington Books. Lexington, Mass., 1976, Chapter 2. (13) Wong, P. S.T.,Chaw, Y.K., Luxon, P. L., Nature (London),253, 263 (1975). (9) Gray,

854

Environmental Science & Technology

(14) Report of the Water Pollution Research Laboratory, Department of Scientific and Industrial Research, Stevenage, England, 1964. (15) Turnbull, H., De Mann, J. G . , Weston, R. F., Ind. Eng. Chern., 43,324-33 (1954). (16) Marchetti, R., Chiaudani, G., Da Gasso, R., De Paolis, A,,

Gaggino, G. F., Gerletti, M., Provini, A,, and Vighi, M., Mar. Pc~llut. Hull., 9, 206 (1978). (17) Goldberg, E. D., Mern., Geol. Soc. Am., 67,345 (1957). (18) Bowen, H. J. M., “Trace Elements in Biochemistry”, Academic Press, New York, 1966. (19) Aberg, B., Hungate, F. P., Eds., “Radioecological Concentration Processes”, Pergamon Press, Oxford, 1967. (20) Patterson, C., Settle, D., “Contribution of Lead via Aerosol Deposition t o the Southern California Bight”, Contribution No. 2426, Publications of the Division of Geological and Planetary Sciences, C.I.T., Pasadena, Calif., 1974. (21) Lowman, F. G., Rice, T. R., Richards, F. A,, “Radioactivity in t h e Marine Environment”, National Academy of Science, LVashington, D.C., 1971, p p 161-99. (22) Bernhard, M., Zattera, A., “Marine Pollution & Marine Waste Disposal”, Pearson, D. H., and Frangipane, E., Eds., Pergamon Press, New York, 1975, p p 195-300. (23) Buck, J. S., Kumro, D. M., “Toxicity of Lead Compounds”, Contribution of the Department of Chemistry at Duke University, Durham, N.C., 1929, p p 161-72. (24) McClain, R. M., Becker, B. A,, Toxicoi. A p p l . Pharrnacol., 21, 266-74 (1972). (25) Galzigna, L., Ferraro, M. V., Manani, G., Viola, A,, Rr J . Ind. Med.. 30, 129-33 (1973). (26) Cremer, J. E., Ann. Occup. Hyg., 3,226-30 (1961). (27) Cremer, J. E., Er. J . I n d . Med., 16, 191-9 (1959). (28) Cremer, ?J. E., Callaway, S., Rr. J . Ind. M c d . , 18, 277-82 (1961). (29) Gething, J., Rr. J . Ind. Med., 32,329-33 (1975).

(30) Manufacturing Chemists Association, “Guide for Safety in the Chemical Laboratory”, Van Nostrand Reinhold Co., New York, 1972, p 433. (31) F A 0 Nutrition Meeting Report Service, No. 61A, FAO, Rome, 1973.

(32) Frassetto, R., Laboratorio Grandi Masse, C.N.R., Venice. 1977, unpublished results. ( 3 3 ) Lo Savio, F., SAIPEM Co., Milan, 1977, private communication. (34) Tiravanti, G., Boari, G., Judicial Report deposited to Otranto Magistrate’s Court, Oct 14, 1976 (in Italian). (35) Zore-Armanda Mira, Institute of Oceanography and Fisheries, S d i t . Yugoslavia. Food and Aericulture Oreanization of the United Nations,Rome, VII, 1968. (36) Talbot, J. W., paper presented at the International Symposium on Discharge of Sewage from Sea Outfalls, London, Sept 1974, Paper No. 32. ( 3 7 ) Patterson, C.. Science. 183.553-4 (1974). (38)Participants, Interlaboratdry Lead Analysis of Standardized Samples of Sea Water, Mar. Chern., 2,69-84 (1974). (39) “Standard Methods for the Examination of \Vater and LVastewater”, 13th ed., American Public Health Association, New York, 1971, pp 210-15. (40) Wedepohl, K. H., Ed., “Handbook of Geochemistry”, 11-4. New York, 1974. (41) Tomislav, K., “Relazione concernente la ispezione a1 relitto della m/n “Cavtat” (Report on the “Cavtat” LVreck Submarine Survey), Brodospas Co., Split, Yugoslavia, Brindisi, Oct 29. 1975 (in Italian). (42) Coates, G. E., “Organo-metallic Compounds”. U‘iley. New York. 1960, pp 200-12. ( 4 3 ) Feldhake, C. J . , Stevens. C. D.. J . Chern. Eng. D a t a , 8, 196 ( 1963).

Received for reiieic, .V‘oi>ernber14, 1978. A c c e p t e d .bfarch 23, 1979.