In order to evaluate the temporary variations, first of the total metal content and second, of the labile fraction, a comparison between sediment results obtained at the same sampling stations in the years 2005 and 1999 was evaluated. For this reason, the quotient between 2005 NEF and 1999 NEF (NEFq) and the quotient between percentages (i.e. each one normalized with respect to total metal concentration) of the labile fraction (LFq) extracted in 2005 and in 1999 were calculated, respectively.
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Figure VI.6. Time changes of the contamination by metals in the surface sediment of the Vigo Ria.
Isoline maps show the NEF of year 2005 divided by NEF of year 1999 to the metal in the fine fraction. The black tick is the no-change isoline, and it corresponds to the same NEF value in both years.
5 km
V
0.9 1.0 1.5 1 5 kmZn
0.8 0.9 0.5 1 2 1 5 kmFe
1 1.0 1.2 5 kmNi
1.0 1.4 1 1.5 3 5 kmCd
2.5 1 1.5 1.1 0.6 2.5Cu
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The main change that occurred during the 1999-2005 period in the Ria environment was the installation and operation of six sewage treatment plants (STP) over the years 1999-2000. Prior to this time, sewage flowed into the Ria (1) directly through 160 sewers in the Vigo harbour and (2) indirectly through wastewaters spilling into the Lagares River. This would explain the distribution maps of NEFq shown in Figure VI.6. In these, it is possible to observe that metal content in surface sediments decreased in most parts of the Ria. An explanation of this behaviour may be the presence of STPs which prevent the entry of suspended particulate matter into the Ria. In the Humber estuary a drop in metal concentration was observed since the STP began functioning (Cave et al., 2005). A similar response has been previously reported for Cd, Cu, Fe and Zn by Blomqvist et al. (1992) and Huh (1996). Nevertheless, some local exceptions to this trend have been detected: Ni and Zn in Rande Strait-San Simón Inlet resulting from the motorway road-bridge over Rande Strait and fish-cages anchored there (Howarth et al., 2005); Cu in the harbour and fishery boats in the main zones as a result of the use of antifouling paint (Valkirs et al., 2003); and Cd in two points without any explanation at present.
The illustration of LFq (Figure VI.7) isolines in the Ria is the opposite of that of NEFq. An increase in metal bioavailability in the sediment was found after the STPs had been in operation for six years, which may be mainly associated with them. Large portions of metals transported in dissolved form or onto fine particles (Huh, 1996) were carried into the Vigo Ria, having been distributed by currents. Iron may be a tracer of these STP spills. Cadmium, Ni and Zn present an increase in the labile metal fraction after this six year period in the outer Ria, from Borneira Point to Home Cape (Figure VI.7). Three steps could be involved in this process: the STP of Cangas (F point in Figure VI.1) which spills metals into the Ria water column; the surface outgoing residual current (Prego and Fraga, 1992; Taboada et al., 1999) which transports the metals toward the northern Ria mouth; and the neighboring mussel raft area where these bivalves are able to sequester metals that are found in fine-grained faecal mud and are ultimately deposited on the adjacent seafloor. In this faecal materialn Zn concentration increases but Pb does not show any variation in LFq, as observed in Amiard et al. (1986). Moreover, some mussel shelves sedimented naturally and pre-treatment processes of mussels onboard rafts may produce enrichment on Ni (Puente et al., 1996). Consequently, the labile fraction (i.e. metals in organic matter and co-precipitated with carbonates) increase in these metals.
In the innermost Ria, i.e. the San Simón Inlet, copper, iron and vanadium exhibited a bioavailability time-increase. These metals reach the Inlet by natural and different anthropogenic sources as Howarth et al. (2005) explained in detail, with agricultural activities being one of the main reasons. The upper sediments of the inlet basin are often disturbed and oxygenated during the harvest season of clams and cockles. Hence, the redox-sensitive metals like V (Tribovillard et al., 2006), Fe and Cu (Guo et al., 1997) tend to be more soluble under oxidizing conditions and less soluble under reducing conditions, which increases the labile fraction.
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Figure VI.7. Time changes of the labile metal levels in the surface sediment of the Vigo Ria. Isoline
maps show the labile metal percentage in the fine fraction for year 2005 divided by the percentage for 1999. The black tick is the no-change isoline, and it corresponds to the same percentage value in both years.
V
5 km 1 3 1.1 0.5 0.5Zn
5 km 2 4 1 0.9 0.9Ni
5 km 1 3 10 15 0.8 1.8Fe
5 km 1.1 0.4 2 2 1 0.5 3Cd
5 km 1 1.5 0.9 3 0.5Cu
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6.4. ConclusionThe industrialized and densely populated Vigo Ria may be a good example of how these types of coastal systems could be affected by anthropogenic influence. Through the total and labile metal content in the sedimentary Ria reservoir it is possible to identify the trace of the natural lithogenic inputs, harbour activities, shipyard works, wastewater flows, wind-borne urban dusts, agricultural contributions, river transports and mariculture production.
Among these combined sources, another noteworthy factor could be the narrow seashore strip in the middle ria where Cd, Cu, and Zn are accumulated in the sediments as a result of the presence of shipyards and docks. In these areas, total metal contamination is from severe to heavy and the labile metal (Cd, Cu, Fe, Ni and Zn) concentrations are the highest in all the Ria. However, the abundance of other metals such as Fe, Ni and V has a natural origin, according to their enrichment factors, as a consequence of the local geological structure. In the southern middle Ria, where no river or sewage inputs are located, as a result of diffuse or uncontrolled dumping, dissolved and particulate metals may be deposited rapidly in the vicinity of discharge points, i.e., port areas, due to changes in pH and salinity. The main freshwater flow, the Oitavén River, at the Ria head is not metal contaminated and this contamination is moderate in the San Simón Inlet in relation to the metal considered.
Another aspect to be highlighted is the presence of the sewage treatment plants which started to operate during the last year of the 20th Century. These plants constitute the most recent change, with notable environmental consequences to the Ria. Six years later, particulate metal in surface sediments was generally observed to decrease, while the labile metal presence has increased. In the northern littoral of the outer Ria in the year 2005, labile Cd, Ni and Zn, probably resulting from the combined action of a sewage plant and a mussel raft area, reached levels of up to 4, 15 and 5 times higher than in 1999, respectively. Another rise in the labile metals was detected in the inner Ria where some redox sensitive metals, such as Cu, Fe and V, increased their bioavailability up to 3 times in six years. This may be due to the agricultural uses and the surrounding network of roads together with the sediment being distrurbed from mariculture activities in the Ria.
Acknowledgements. The authors would like to express their gratitude to R/V
Mytilus crew, METRIA project participants, Paloma Herbello and Monserrat Martínez for their help with the sampling; to Clemente Trujillo and Paula Ferro for the technical and analysis assistance. Dra. Filgueiras and Ph. D. Santos- Echeandia would like to thank the Spanish Education and Science Ministry (I3P researcher contract) and Basque Government (Predoctoral Grant), respectively, for their financial support Graduate Santos for This work is a contribution to the Spanish LOICZ program and was supported by CICYT under the project ‘Biogeochemical budget and 3D transport model of trace metals in a Galician Ria’ (Acronym: METRIA, reference REN2003-04106-C03).
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ReferencesAckerman, F., 1980. A procedure for correcting the grain size effect in heavy metal analyses of estuarine and coastal sediments.
Environmental Technology Letters 1, 518-527.
Ahnstrom, Z.S., Parker, D.R., 1999. Development and assessment of a sequential extraction procedure for the fractionation of soil cadmium. Soil Science
Society of America Journal 63,
1650-1658.
Amiard, J.C., Amiardtriquet, C., Berthet, B., Metayer, C., 1986. Contribution to the ecotoxicological study of cadmium, lead, copper and zinc in the mussel Mytilys-Edulis. 1. Field study. Marine Biology 90, 425-431.
Alvarez-Iglesias, P., Rubio, B., Vilas, F., 2003. Pollution in intertidal sediments of San Simón Bay (Inner Ria de Vigo, NW of Spain): total heavy metal concentrations and speciation.
Marine Pollution Bulletin 46,
491-521.
Balls, P.W., Hull, S., Miller, B.S., Pirie, F.M., Proctor, W., 1997. Trace metal in Scottish estuarine and sediments. Marine Pollution
Bulletin 348, 42-50.
Bay, S.M., Zeng, E.Y., Lorenson, T.D., Tran, K., Alexander, C., 2003. Temporal and spatial distributions of contaminants in sediments of Santa Monica Bay, California. Marine Environmental
Research 56, 255-276.
Barciela-Alonso, M.C., Pazos- Capeáns, P., Regueira-Miguens, M.E., Bermejo-Barrera, A., Bermejo-Barrera, P., 2004. Study of cadmium, lead and tin
distribution in surface marine sediment samples from Ria de Arousa (NW of Spain). Analytica
Chimica Acta 524, 115-120.
Belzunce-Segarra, M.J., Bacon, J.R., Prego, R., Wilson, M.J., 1997a. Chemical forms of heavy metals in surface sediments of the San Simón inlet, Ría de Vigo, Galicia.
Journal of Environmental Science and Health A32, 1271-
1292.
Belzunce-Segarra, M.J., Capelo, J.L., Prego, R., 1997b. El ciclo del hierro en la ensenada de San Simón. In: R. Prego, J.M. Fernández Procesos Biogeoquímicos en sistemas costeros Hispano-Lusos, pp. 57- 62. Pontevedra: Diputación de Pontevedra – CSIC.
Bernárdez, P., Prego, R., Frances, G., González-Álvarez, R., 2005. Opal content in the Ria de Vigo and Galician continental shelf: biogenic silica in the muddy fraction as an achúrate paleoproductivity proxy.
Continental Shelf Research 25,
1249-1264.
Bolton, J.L., Stehr, C.M., Boyd, D.T., Burrows, D.G., Tkalin, A.V., Lishavskaya, T.S., 2003. Organic and trace metal contaminants in sediments and English sole tissues from Vancouver Harbour, Canada.
Marine Environmental Research
57, 19-36.
Blomqvist, S., Larson, U., Borg, H., 1992. Heavy metal decrease in the sediments of a Baltic Bay following tertiary sewage treatment. Marine Pollution Bulletin 24, 258-266.
Temporal and spatial changes of total and labile metal concentration in the surface sediments of the Vigo Ria (NW Iberian Peninsula): Influence of anthropogenic sources
150
Canario, J., Prego, R., Vale, C., 2007. Distribution of mercury and monomethylmercury in sediments of Vigo Ria, NW Iberian Peninsula. Water, Air,
and Soil Pollution 182, 21-29.
Carballeira, A., Carral, E., Puente, X., Villares, R., 2000. Regional- scale monitoring of coastal contamination. Nutrients and heavy metals in estuarine sediments and organisms on the coast of Galicia (northwest Spain). International Journal of
Environment and Pollution 13,
534-572.
Carral, E., Puente, X., Villares, R., Carballeira, A., 1995. Background heavy metal levels in estuarine sediments and organisms in Galicia (northwest Spain) as determined by modal analysis. The Science of the
Total Environment 172, 175-188.
Cave, R.R., Andrews, J.E., Jickells, T, Coombes, E.G., 2005. A review of sediment contamination by trace metals in the Humber catchment and estuary, and the implications for future estuary water quality.
Estuarine Coastal and Shelf Science 62, 547-557.
Cobelo-García, A., Prego, R., 2003. Heavy metal sedimentary record in a Galician Ria (NW Spain): background values and recent contamination. Marine Pollution
Bulletin 46, 1253-1262.
Diz, P., Francés, G., Rosón, G., 2006, Effects of contrasting upwelling-downwelling on benthic foraminiferal distribution in the Ría de Vigo. Journal of
Marine Systems 60, 1-18.
Doherty, G.B., Coomans, D., Brunskill, G.J., 2000. Modelling natural and enhanced trace
metal concentrations in sediments of Cleveland Bay, Australia. Marine and Freshwater Research 51, 739-
747.
EPA 1996. Method 3052. Microwave assisted acid digestion of siliceous and organically based matrices. Available from <www.epa.gov/epaoswer/hazwa ste/test/3052.pdf>
Evans, G., Howarth, R.J., Nombela, M.A., 2003. Metals in the sediments of Ensenada de San Simón (inner Ría de Vigo), Galicia, NW Spain. Applied Geochemistry 18, 973-996. Evans, G., Prego, R., 2003. Rias,
estuaries and incised valleys: is a ria an estuary? Marine
Geology 196, 171-175.
Fairbridge, R.W., 1980. The Estuary: its definition and geodynamic cycle. In: E. Olausson, I. Cato Chemistry and Biogeochemistry of Estuaries, pp. 1-36. Bath: John Wiley & Sons.
Feng, H., Cochram, K., Lwiza, H., Brownawell, B.J., Hirschberg, D.J., 1998. Distribution of heavy metal and PCB contaminants in the sediments of an urban estuary: the Hudson River.
Marine Environmental Research
45, 69-88.
Filgueiras, A.V., Lavilla, I., Bendicho, C., 2002. Chemical sequential extraction for metal partitioning in environmental solid samples. Tutorial Review. Journal of
Environmental Monitoring 4,
823-857.
Förstner, U., 1987. Sediment- associated contaminants. An overview of basis for developing remedial options. Hydrologia 149, 221-246.
Part II; Chapter 6
151
Floor, P., 1966. Petrology of an Aegirine Riebeckite Gneiss- Bearing part of the hesperian massif: The Galiñeiro and Surrounding Areas, Vigo, Spain.
Leidse Geologische Mededelingen 36, 1-204.
Fraga, F., 1976. Primary production in Ria de Vigo. Investigación Pesquera 40, 151-167.
Fraga, F., 1981. Upwelling of the Galician coast, Northwest Spain. In: F.A. Richards Coastal upwelling, vol.1, pp. 176-182. Washington: Coastal Estuarine Science, AGU.
Gago, J., Alvarez-Salgado, X.A., Gilcoto, M., Pérez, F.F., 2003. Assessing the contrasting fate of dissolved and suspended organic carbon in a coastal upwelling system (‘‘Ría de Vigo’’, NW Iberian Peninsula).
Estuarine, Coastal and Shelf Science 56: 271-279
Guo, T., Delaune, R.D., Patrick Jr., W.H., 1997. The effect of sediment redox chemistry on solubility/chemically active forms of selected metals in bottom sediment receiving produced water discharge. Spill Science &
Technology Bulletin 4, 165-175.
Hakanson, L., 1980. An ecological risk index for aquatic pollution control. A sedimentological approach. Water Research 14, 975-1001.
Hanson, P.J., Evans, D.W., Colby, D.R., 1993. Assessment of elemental contamination in estuarine and coastal environments based on geochemical and statistical modeling of sediments. Marine
Enviromnental Research 36,
237-266.
Hölemann, J.A., Schirmacher, M., Kassens, H., Prange, A., 1999 Geochemistry of surficial and ice-rafted sediments from the Laptev Sea (Siberia). Estruarine,
Coastal and Shelf Science 49,
45-59.
Hornberger, M.I., Luoma, S.N., Van Geen, A., Fuller, C., Anima, R., 1999. Historical trends of metals in the sediments of San Francisco Bay, California.
Marine Chemistry 64, 39-55.
Hornberger, M.I., Luoma, S.N., Cain, D.J., Parchaso, F., Brown, C.L., Bouse, R.M., Wllise, C, Thompson, J.K., 2000. Linkage of bioaccumulation and biological effects to changes in pollutant loads in South San Francisco Bay. Environmental
Science and Technology 34,
2401-2409.
Howarth, R.J., Evans, G., Croudace, I.W., Cundy, A.B., 2005. Sources and timing of anthropogenic pollution in the Ensenada de Sna Simón (inner Ría de Vigo), Galicia, NW Spain: an application of mixture- modelling and nonlinear optimization to recent sedimentation. Science of the
Total Environment 340, 149-176.
Huh, C.A., 1996. Fluxes and budgets of anthropogenic metals in the Santa Monica and San Pedro Basins off Los Angeles: review and reassessment. The Science
of the Total Environment 179,
47-60.
Lacey, E.M., King, J.W., Quinn, F.G., Mecray, E.L., Appleby, P.G., Hunt, A.S., 2001. Sediment quality in Burlington Harbor, Lake Champlain, U.S.A. Water, Air, and Soil Pollution 126, 97- 120.
Temporal and spatial changes of total and labile metal concentration in the surface sediments of the Vigo Ria (NW Iberian Peninsula): Influence of anthropogenic sources
152
Loring, D.H., 1991. Normalization of heavy-metal data from estuarine and coastal sediments. ICES
Journal of Marine Science 48,
101-115.
Luoma, S.N., Dagovitz, R., Axtaman, E., 1990. Temporally intensive study of trace metals in sediments and bivalves from a large river-stuarine system: Suisun Bay/Delta in San Francisco Bay. The Science of
the Total Environment 97-8, 685-
712.
Maggi, C., Bianchi, J., Dattolo, M., Mariotti, S., Cozzolino, A., Gabellini, M., 2006. Fractionation studies and bioaccumulation of cadmium, mercury and lead in two harbour areas. Chemical Speciation and
Bioavailability 18, 95-103.
Mason, R.P., Kim, E.H., Cornwell, J., 2004. Metal accumulation in Baltimore Harbor: current and past inputs. Applied
Geochemistry 19, 1801-1825.
Marmolejo-Rodríguez, J., Cobelo- García, A., Prego, R., 2007. Background values, distribution and contamination of metals in the sediments of the Pontevedra Ría (NW Spain). Journal of
Sediment and Soil Contamination 16(6), 557-568.
McCready, S., Birch, G.F., Long, E.R., Spyrakis, G., Greely, C.R., 2006. Relationships between toxicity and concentrations of chemical contaminants in sediments from Sydney Harbour, Australia, and vicinity.
Environmental Monitoring and Assessment 120, 187-220.
Montero, P., Floor, P., Corretge, G., 1998. The accumulation of rare- earth and high-field-strength elements in peralkaline granitic
rocks: The Galiñeiro orthogneissic complex, northwestern Spain. Canadian
Mineralogist 36, 683-700.
Morillo, J., Usero, J., Gracia, I., 2002. Heavy metal fractionation in sediments from the Tinto River (Spain). International Journal of Environmental
Analytical Chemistry 82, 245-
257.
Morillo, J., Usero, J., Gracia, I., 2004. Heavy metal distribution in marine sediments from the southwest coast of Spain.
Chemosphere 55, 431-442.
Naidu, A.S., Blanchard, A., Kelley, J.J., Goering, J.J., Hameedi, M.J., Baskaran, M., 1997. Heavy metals in Chukchi Sea sediments as compared to selected circum-arctic shelves.
Marine Pollution Bulletin 35,
260–269.
Nombela, M.A., Vilas, F., Evans, G., 1995. Sedimentation in the mesotidal Rias Bajas of Galicia
(North-western Spain): Ensenada de San Simón, inner
Ria de Vigo. Spec. Publs int. Ass. Sediment. 24, 133-149. Palanques, A., Díaz, J.I., 1994.
Anthropogenic heavy metal pollution in the sediments of the Barcelona continental shelf (Northwestern Mediterranean).
Marine Environmental Research
38, 17-31.
Pazos, O., Nombela, M.A., Vilas, F., 2000. Continental contribution of suspended sediment to an estuary: Ría de Vigo. Scientia
Marina 64, 295-302.
Prego, R., 1993. Biogeochemical Pathways of Phosphate in a Galician Ria (North-western Iberian Peninsula). Estuarine,
Part II; Chapter 6
153
Coastal and Shelf Science 37,
437-451.
Prego, R., Cobelo-García, A., 2003. Twentieth century overview of heavy metals in the Galician Rias (NW Iberian Peninsula).
Environmental Pollution 121,
425-452.
Prego, R., Fraga, F., 1992. A simple- model to calculate the residual flows in a Spanish Ria – Hydrographic consequences in the Ria de Vigo. Estuarine
Coastal and Shelf Science 34,
603-615.
Prego, R., Barciela, M.D., Varela, M., 1999. Nutrient dynamics in the Galician coastal area (Northwestern Iberian Peninsula): Do the Rias Bajas
receive more nutrient salts than the Rias Altas? Continental Shelf
Research 19, 317-334.
Prego, R., Bao, R., Howland, R., 1995. The biogeochemical cycling of dissolved silicate in a Galician Ria. Ophelia 42, 301- 318.
Prego, R., Otxotorena, U., Cobelo- García, A., 2006. Presence of Cr, Cu, Fe and Pb in sediments underlying mussel-culture rafts (Arosa and Vigo rias, NW Spain). Are they metal- contaminated areas? Ciencias
Marinas 32, 339-349.
Prego, R., Ferro, P. and Trujillo, C., 2008. Lead and Zinc contamination of surface sediments in the main harbours of the Galician Rias. Journal of
Iberian Geology 34(2), 243-252.
Puente, X., Villares, R., Carral, E., Carballeira, A., 1996. Nacreous shell of Mytilus galloprovincialis as a biomonitor of heavy metal pollution in Galiza (NW Spain).
The Science of the Total
Environment 183, 205-211.
Quevauviller, Ph., Rauret, G., Lopez- Sanchez, J.F., Rubio, R., Ure, A.M., Muntau, H., 1997. The certification of the EDTA- extractable contents (mass fractions) of Cd, Cr, Ni, Pb and Zn in sediment following a three- step sequential extraction procedure. Report EUR 17554 EN. Brussels: European Commission.
Repetto, M., 1995. Toxicología avanzada. Madrid: Díaz de Santos.
Río Barja, F.J., Rodríguez Lestegás, F., 1992. Os ríos galegos. Morfoloxía e réxime. Santiago de Compostela: Consello da Cultura Galega.
Rubio, B., Nombela, M.A., Vilas, F., 2000. Geochemistry of major and trace elements in sediments of the Ría de Vigo (NW Spain): an assessment of metal pollution. Marine Pollution Bulletin 40, 968-980.
Salomons, W., Förstner, U., 1984. Metals in the Hydrocicle. Berlin: Springer-Verlag.
Salomons, W., Kerdijk, H., Van Pagee, H.Y., Schreur, A., 1985. Behaviour and impact assessment of heavy metals in estuarine and coastal zones. In U. Seeliger, L.D. De Lacerda, S.D. Patchineelam Metals in Coastal environments of Latin America, pp. 157-198. Berlin: Springer-Verlag.
Sari, E., Çagatay, M.N., 2001. Distributions of heavy metals in the surface sediments of the Gulf of Saros, NE Aegean Sea.
Environmental International, 26,
Temporal and spatial changes of total and labile metal concentration in the surface sediments of the Vigo Ria (NW Iberian Peninsula): Influence of anthropogenic sources
154
Sposito, G., 1989. Surface-reactions in natural aqueous colloidal systems. Chimia 43, 169-176. Stone, M., Droppo, I.G., 1996.
Distribution of lead, copper and zinc in size-fractionated river bed sediment in two agricultural catchments of southern Ontario, Canada. Environmental Pollution 93, 353-362.
Sutherland, R.A., Tack, F.M.G., Tolosa, C.A., Verloo, M.G., 2000. Operationally defined metal fractions in road deposited sediment, Honolulu, Hawaii.
Journal of Environmental Quality
29, 1431-1439.
Taboada, J.J., Prego, R., Ruiz- Villarreal, M., Gómez-Gesteira, M., Montero, P., Santos, A.P., Pérez-Villar, V., 1998. Evaluation of the seasonal variations in the residual circulation in the Ría de Vigo (NW Spain) by means of a 3D baroclinic model. Estuarine,
Coastal and Shelf Science 47,
661-670.
Tanner, P.A., Leong, L.S., Pan, S.M., 2000. Contamination of heavy metals in marine sediment cores from Victoria Harbour, Hong Kong. Marine Pollution
Bulletin 40, 769-779.
Tribovillard, N., Algeo, T.J., Lyons, T., Reboulleau, A., 2006. Trace metals as paleoredox and paleoproductivity proxies: An update. Chemical Geology 232, 12-32.
Turner, A., Olsen, Y.S., 2000. Chemical versus enzymatic digestion of contaminated estuarine sediment: relative importance of iron and manganese oxides in controlling trace metal bioavailability.
Estuarine, Coastal and Shelf Science 51, 717-728.
Ure, A.M., Davidson, C.M., 2001. Chemical Speciation in the Environment. Glasgow: Blacki. Usero, J., Gamero, M., Morillo, J.,
Gracia, I., 1998. Comparative study of three sequential extraction procedures for metals in marine sediments.
Environmental International 24,
487-496.
Valkirs, A.O., Seligman, P.F., Haslbeck, E., Caso, J.S., 2003. Measurement of copper release rates from antifouling paint under laboratory and in situ conditions: implications for loading estimation to marine water bodies. Marine Pollution Bulletin