Distribution of heavy metals in sediments of the Patraikos gulf (Greece)

Marine Pollution Bulletm, Vo[. 14, No. 1, pp. 33-35, 1983 Printed in Great Britain

0025 326X '83;010033 03 $03.00/0 © 1983 Pergamon Press Ltd.

Distribution of Heavy Metals in Sediments of the Patraikos Gulf (Grccce) In August 1980 and February 1981, sediment samples were collected at 21 stations in the Greek gulf of Patraikos (Fig. 1), using a 0.1m 2 van Veen grab. After drying at 105°C, part of each sample was submitted to a grain size analysis, according to the procedure described by Buchanan (1971). The remainder was crushed in a mortar to pass a 0.45mm nylon sieve. For the determination of the heavy metals, 5g of the material was shaken with 75 ml of 2 N hydrochloric acid for 16 h in the cold, then the volume was brought to 100 ml with water. The loss of weight was deemed to represent calcium carbonate. The concentration in the filtered solution was estimated directly with a Perkin-Elmer 305 B A.A.S., equipped with a deuterium background corrector, except in the case of cadmium, which required the use of the graphite furnace. The technique employed was that of Satsmadjis & Voutsinou-Taliadouri (1981). Organic carbon was determined by the method of Gaudette etal. (1974). All samples were analysed twice.

Table 1 indicates the reproducibility of the determination of organic carbon, calcium carbonate and the heavy metals in a representative sediment sample. In the case of the metals, figures relating to nitric acid extraction are also quoted. The procedure consists of digesting 1 g of sediment in 50 ml of conc. nitric acid for a few hours just below the boiling point. Its accuracy has been established in several intercalibration exercises. However, the treatment with hydrochloric acid, which gives nearly the same results, was preferred, because of its higher precision and greater convenience. Table 2 demonstrates that the sediment in the Patraikos Gulf presents little variation in grain size (16 stations out of 21 have less than 2% sand), organic carbon (mean 0.67%) and calcium carbonate (mean 34%). Table 3 indicates that, as a rule, the concentration of the heavy metals does not change much throughout the Gulf. It tends to rise in its central part, where the sediment is finer and the depth greater. Neither the port of Patras nor the rivers perceptibly disturb this simple pattern. The levels of the metals resemble those in the East Aegean Sea, but they are only about half those in the Pagassitikos Gulf,

TABLE 1 Precision a n d a c c u r a c y o f the d e t e r m i n a t i o n s (representative sediment s a m p l e a n a l y s e d 10 timesL

Organic carbon (%) C a l c i u m c a r b o n a t e 1%) C o b a l t ( m g kg - 1) C h r o m i u m ( m g k g - 1) C o p p e r ( m g k g - 1) I r o n (%0) M a n g a n e s e ( m g k g t) Nickel (rag k g - t) L e a d ( m g k g - I) Z i n c (mg k g t)

Mean of determin,

S.D.

0.64 32.6 18.8 82.0 27.3 23.2 1680.0 98.0 16.3 69.0

0.014 1.14 1.18 2.53 1.27 1.02 66.00 4.50 1.15 4.19

Coeff. var.

Mean

2.2 3.5 6.0 3.0 5.0 4.0 4.0 5.0 7.0 6.0

Nitric acid e x t r a c t i o n S.D.

C o e f f . var.

2.6 13.0 3.7 1.7 70.0 18.0 1.3 9.0

13 14 11 7 4 16 8 12

20.1 91.0 33.3 23.9 1780.0 112.0 16.8 72.0

TABLE 2 G r a i n size, o r g a n i c c a r b o n a n d c a l c i u m c a r b o n a t e in the sediments. Organic,carbon (%)

G r a i n size ( % ) Stat. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Latitude 38o19 ' 38015 ' 38019 ' 38016 ' 38014 ' 38o12 ' 38019 ' 38016 ' 38°14 ' 38°12 ' 38°10 ' 38017 ' 38o16 ' 38014 ' 38o12 ' 38°18 ' 38°16 ' 38o14 ' 38017 ' 38016 ' 38015 '

Longitude 021o45 ' 021043 ' 021°41 ' 021041 , 021o41 ' 021041 ' 021035 ' 021035 ' 021°35 ' 021035 ' 021°35 ' 021030 ' 021030 ' 021o30 ' 021o30 , 021025 ' 021025 ' 021o25 ' 021019 ' 021020 ' 021o21 '

CaCO 3 (%)

Depth (m)

Sand

Silt

Clay

A u g . 80

Feb. 81

Mean

A u g . 80

Feb. 81

Mean

70 50 52 64 83 40 52 76 111 81 11 43 86 115 60 34 81 54 32 44 48

45.7 1.0 0.2 0.5 0.3 0.3 0.2 0.1 0.0 0.0 0.0 7.0 1.5 0.7 1.2 5.1 1.2 21.9 8.2 1.8 6.0

25.5 46.8 45.0 37.2 40.0 43.7 34.7 43.9 24.9 38.0 35.4 51.8 47.5 34.5 33.0 61.0 50.0 47.1 53.3 60.0 53.5

28.8 52.2 54.8 62.3 59.7 56.0 65.1 56.0 75.1 62.0 64.6 41.2 51.1 64.8 65.8 33.9 48.8 31.0 38.5 38.2 40.5

0.53 0.74 0.36 0.77 0.54 0.59 0.77 0.46 0.83 0.64 0.84 0.67 0.66 0.73 0.57 0.42 0.43 0.89 0.72 0.44 0.67

0.34 0.82 0.71 0.79 0.76 0.79 0.78 0.70 0.67 0.67 0.80 0.73 0.77 0.79 0.88 0.54 0.69 0.86 0.50 0.51 0.59

0.43 0.78 0.53 0.78 0.65 0.69 0.77 0.61 0.75 0.66 0.82 0.70 0.72 0.76 0.73 0.48 0.56 0.87 0.61 0.48 0.63

34.7 34.1 33.0 34.4 33.6 34.2 33.0 36.3 36.8 33.8 31.8 34.9 33.8 33.8 36.0 28.9 34.1 31.3 34.4 32.9 34.0

36.9 35.1 32.0 35.0 34.5 33.5 35.0 36.5 36.3 35.7 32.9 33.5 33.5 35.1 33.9 31.2 34.4 30.1 32.6 30.6 32.0

35.8 34.6 32.5 34.7 34.1 33.9 34.0 36.4 36.6 34.8 32.3 34.2 33.6 34.4 34.9 30.0 34.2 30.7 33.5 31.7 33.0

33

0

o"

8

~ ~ o o o

~ o o ~ ~ ~ § ~ o o o

1

I

m

J~

I

i

oo

0

j~

o~

c~

0

~u

3

©

o

J~

0

0

Volume 14/Number l/January 1983

except in the instance of Mn, which is the same in both regions. The authors wish to thank Constantine Bogdanos for collecting the samples. Spyros Stavrakakis for carrying out the grain size determinations, Eustathius Hadjigeorgiou for helping with the other analyses and Basel Marouda Lambropoulou for drawing the map.

Institute of F A N N Y VOUTSINOU- T A L I A D O U R I Oceanography and Fisheries J O H N SATSMADJIS Research, Agios Kosmas, Athens, Greece

Buchanan, J. B. (1971). Sediments. In Methods f o r the Study o f Marine Benthos (N. A. Holme and A. Mclntyre, eds.), pp. 35-39. IBP handbook No. 16. Oxford University Press, Oxford. Gaudette, H., Flight, W., Tones, L. & Folger, D. (1974). An inexpensive titration method for the determination of organic carbon in recent sediments. J. sedim. PetroL, 44, 249-253. Satsmadjis, J. & Voutsinou-Taliadouri, F. (1981). Determination of trace metals at concentrations above the linear calibration range by electrothermal atomic absorption spectromelry. Analvtica chim. Acta, 131, 83-90.

MarinePollutionBulletin, Vol. 14, No. 1, 35-36, 1983 Printed in GreatBritain

Selenium in Marine Organisms from St Vincent's Gulf, South Australia In recent years anthropogenic inputs of selenium to the marine environment have increased (Bertine & Goldberg, 1971; Gissel-Nielsen & Gissel-Nielsen, 1973) and selenium is now considered to be a potential marine pollutant (Fowler & Benayoun, 1976b). Selenium is of interest as it is classified as an essential element for animals (Schwartz & Faltz, 1957) but is toxic at elevated levels (Schroeder & Mitchener, 1971) and may be carcinogenic (Shapiro, 1972). At present there are few reported measurements of selenium concentrations in marine organisms (Lunde, 1970; Schroeder etal., 1970; Sandholm etal., 1973; Mackay etal., 1975), while relatively little is known about the behaviour of this element within marine organisms (Lunde, 1970, 1972, 1973; Fowler & Benayoun, 1976 a, b, c; Wrench, 1978, 1979). To obtain information on the concentrations of selenium existing in marine organisms and to establish natural background levels, specimens were collected from St Vincent's Gulf, South Australia, and the selenium contents determined.

Materials and Methods Organisms were collected from St Vincent's Gulf, South Australia, during August-December 1981. All organisms were separated into component tissues and stored at - 2 ° C until analysed. Samples were freeze dried and ground (to < 200 ~m) before analysis. After digestion of organic matter with nitric and perchloric acids, selenium was isolated by coprecipitation with lanthanum hydroxide, then a piazselenol was formed between selenium and 2-3-diaminonaphthalene at pH 1.0 and extracted into cyclohexane. Selenium was determined fluorometrically 0-ex, 377 nm; ~em519 nm) in the extract. The detection limit of the method was 3.6 ng and the coefficient of variation 4070at the 10 ng level. The accuracy of the determination procedure has been previously assessed by recovery experiments and the analysis of a standard reference material (Maher, 1982). Recoveries of selenium added to selected marine tissues (fish, scallops and macroalgae) were in the range of 97-100°70. The selenium concentration obtained by replicate analysis of

0025-326X/83/0100354)2 $03.00/0 PergamonPressLtd.

Orchard Leaves, NBS SRM 1571 was 0.076 +0.002 mg/kg and in agreement with the certified value (0.08 +0.01 mg/kg).

Results and Discussion No organisms showed unusually elevated levels of selenium (Table 1) but the present results indicate that selenium concentrations are higher in the muscle and digestive tissues of crustaceans (average 3.3 mg kg- 1and 2.7 mg kg- t) than in the other organisms examined (average 1.3 mg kg-1 and 1.8 mg kg-1). It has been shown in several studies (Sandholm et al., 1973; Wrench et al., 1979) that the rate of uptake of organometallic forming elements, such as selenium, via food or water can influence the metabolism and subsequent accumulation of the element. Thus the differences in selenium concentrations found in different tissues may be a reflection of the mode of intake, as while crustaceans are scavengers and ingest sediment particles, fish and molluscs are primarily filter feeders. In general, TABLE 1 Selenium concentrations in marine organisms. Number Selenium of (mg kg J dry wt) samples Range mean

Sample Pisces Hemirhamphusaustralis

Muscle Digestive system Muscle Digestive system Muscle Digestive system Muscle Digestive system

5 5 5 5 4 4 3 3

Muscle Muscle Digestive system Crangon novae zelandiae Muscle Helograpsus sp. Muscle Soft tissue Callogobius mucosus Muscle Soft tissue

Sillaginodespunctatus Arripisgeorgianus Callogobius mucosus

0.56-0.81 1.3 -2.0 1.1 -1.7 2.0 -2.6 0.72-0.98 I. 1 -1.8 0.40-0.63 0.79-1.2

0.72 1.8 1.5 2.4 0.84 1.6 0.49 0.99

10 3 3 3 4 4 4 4

3.7 2.5 3.0 3.4 1.8 1.6 3.0 2.6

-5.6 -2.9 -3.5 -3.9 -3.3 -2.7 -3.6 -3.2

4.4 2.7 3.2 3.6 2.4 2.0 3.2 2.8

Muscle Viscera Muscle Viscera

10 10 10 10

0.7 1.1 1.6 1.4

-1.5 -2.3 -2.5 -2.7

1.1 1.6 2.3 2.5

Muscle

4

0.9 -2.6

2.1

Crustacea Penaeus latisuleatus Jasus novae hollandiae

Mollusca Mytilusedulisplanulatus

Pecten alba Cephalopoda Sepioteuthis australis

35