(2) Lees, H., Quastel, J. H., Biochem. J . , 40,815 (1946). (3) Quastel, J. H., Scholefield, P. G., Bacterid. Rev., 15, l(1951). (4) Allison, F. E., Doetsch, J. H., Roller, E. M., Soil Sci., 72, 187 (1951). (5) Allison, F. E., Kefauves, M., Roller, E. M., Soil Sci. Soc. Am. Proc., 17,107 (1953). (6) Allison, F. E., Roller, M. E., Doetsch, J. H., Soil Sci., 75, 173 (1953). (7) Allison, R. E., Doetsch, J. H., Roller, M. E., ibid., p 373. (8) Bower, C. A,, Soil Sci. SOC.Am. ?roc,,, 15,99 (1951). (9) Goldberg, S. S., Gainey, P . L., Soil Scc., 80,43. (10) Koon, J. H., Kaufman, W. J., “Optimization of Ammonia Removal by Ion Exchange Using Clinoptilolite”, SERL Report No. 71-5, University of California, Berkeley, Calif., Sept. 1971. (11) Painter, H. A., Water Res., 4,393 (1970). (12) Lipman, C. B., Burgess, P. S., Centralbl. Bakteriol. I I Abt., 41. (13) Meiklejohn, J., “Some Aspects of the Physiology of the Nitrifying
Bacteria”, Symp. on Autotrophic Organisms, pp 68-83, Cambridge Univ. Press, London, England, 1954. (14) Mills, E. V., Wheatland, A. B., Water Waste Treat. J., 9, 170 (1962). (15) Coleman, D. A., Soil Sci., 4,345 (1917). (16) Loveless, J. E., Painter, H. A., J . Gen. Microbiol., 52, 1 (1968). (17) Finstein, M. S., Bitzky, M. R., Water Res., 6,31 (1972). (18) Chen, M., Carelli, E., Fuhs, G. W., J . Wat. Pollut. Control Fed., 47,2474 (1975). (19) McCarty, P. L., Kugelman, I. J., Lawrence, A. W., “Ion Effects in Anaerobic Digestion”, Technica! Report No. 33, Dept. of Civil Eng., Stanford University, Stanford, Calif., 1964. (20) Zobell, C. A,, J . Bacteriol., 46, 39 (1943).
Received for revieur January 5 , 1976. Accepted September 7, 1976. Work supported by the University o f Illinois Water Resources Center, State Project Number S-044-ILL.
Heavy Metal Concentrations in Water, Sediments, and Fish from Mediterranean Coastal Area, Israel lgal Roth and Hava Hornung* Israel Oceanographic & Limnological Research Ltd., Haifa Laboratories, P.O.B. 1793, Haifa, Israel
Samples of water, sediment, and fish were collected along the northern part of the Mediterranean coast of Israel and analyzed for cadmium, lead, copper, zinc, nickel, and chromium by atomic absorption spectrophotometry. The obtained values showed no significant heavy metal pollution in the studied area, compared with values found in literature for metal concentrations in other parts of the world. The Bay of Haifa receives domestic, industrial, agricultural, and natural runoff from a heavily populated and fairly industrialized area. The Qishon and Na’aman Rivers, both flowing to the Haifa Bay area, are heavily polluted, the former by industries and the latter by agriculture and domestic sewage. The Bay is also an important fishing ground for trawl, pelagic, and reef fishes. Trace elements introduced into the marine environment from effluents and river runoff may be concentrated in marine organisms by a factor ranging from 1 000 to 10 000 ( I ) . Metal concentrations in water and sediments of four streams and estuaries were studied by Roth and Hornung (2). Of these, only the Na’aman River flows into Haifa Bay. The values for metal concentations (Cd, Pb, Cu, Zn, Ni, and Cr) in the water and sediments of the Na’aman River were similar to, or only slightly higher than, those found along the Israeli shore. Since no previous data on the concentration of trace elements in the Bay of Haifa are available, this survey was undertaken to initiate a routine monitoring of the heavy metal concentration in that Bay. Water, sediment, fish, and random samples of algae were collected to determine the trace metal concentrations. The primary objective of the fish analyses was to ascertain whether the most commonly caught species contained concentrations of heavy metals hazardous to public health, and to establish the general levels and ranges for each of the metals in the edible parts of fish species. Materials and Methods
Nearshore samples of water and sediments were collected a t stations between Rosh Hanikra and Haifa. Fishes were collected from catches taken along the whole Mediterranean coast of Israel. Samples of some common marine algae were
collected a t the water’s edge on the Nahariya, Acre, and Haifa seashores. Water Samples. Surface seawater was sampled with a plastic bucket, and subsurface samples with Niskin PVC water bottles. The water for determination of Cd, Pb, Cu, Zn, and Ni was filtered through a 0.45-wm membrane filter immediately after sampling, so that there was no need to test the possible adsorption of the metals onto the containers. Each 2-1. sample was then passed through a glass column containing ion-exchange resin (Chelex-100) and treated according to the procedure outlined by Riley and Taylor ( 3 ) .The resulting solutions were then analyzed by atomic absorption spectroscopy. The analyzed filters showed low values of the adsorbed metal. The blanks and efficiency of the columns were determined on stripped seawater (filtered seawater which passed the Chelex-100 resin). Part of this water was spiked with known amounts of metals to be analyzed a t levels approximating twice their seawater concentrations. The spiked samples were analyzed in the same way as the other samples. The efficiency of this procedure and the limit of detection for each metal are given in Table I. The values of the blanks were below the limit
Table 1. Percent Efficiency for Concentration of Metals with Chelex-100 Resin Experiment no.a
I I1 111 IV V VI VI1 Mean value Standard deviation % coefficient of variation Standard error Limit of detection (ppb) a
Cd
88.0 84.4 83.3 84.9 88.9 83.9 79.2 84.7 3.2 3.8 1.2 0.6
Pb
Cu
Zn
81.7 78.5 87.8 87.0 86.0 86.6 92.3 86.2 80.0 80.0 86.7 76.2 72.6 87.6 65.8 72.2 89.1 68.2 82.2 84.0 78.0 79.6 86.8 8.4 6.8 1.6 11.0 8.5 1.9 0.6 3.2 2.6 20 2 2
Ni
82.5 89.9 92.7 84.2 73.5 78.5 83.6 7.1 8.5 2.9 8
Each experiment was replicated.
Volume 1 1 , Number 3,March 1977
265
Table II. Trace Element Concentration in Waters of Northern Israeli Coast Compared with Other Regions in the World in pg/I. (ppb) Drinking water standards ( 73)
Unpolluted seawater ( 74- 16) Present work, northern shoreline Present work, average Mediterranean off Crete ( 77) Red Sea, surface ( 7 7 ) Suez Canal ( 77) Ligurian Sea ( 78) Adriatic Sea, coast & Gulf of Trieste ( 79, 20) English coast, Liverpool Bay (27) English coast, Bristol Channel (27) Clyde Bay, Scotland (22) Menai Straits, Wales (23) Irish Sea, shoreline (24) Northeast Atlantic (25) Northeast Atlantic, nearshore (26, 27) Monterey Bay, California (28) California & Florida, shoreline (29, 30) Hong Kong, shoreline (3 7) a
Cd
Pb
cu
Zn
10 0.1 1 0.6-2.9 0.94
50 0.03 2.1-11.4 6.4
100 3.0 0.8-31.2 3.7 0.65 0.2-0.4 3.9 0.7-4.8
1000 10.0 1.0-256.0 38.3 24.7 2.4-24.8 40.0 3.3-86.0
0.14-0.74 0.3-4.2 0.01-0.18 0.03-1.4 0.07-0.71 0.04-0.3 0.02-4.7 45
0.5-5.0 0.7-4.2 0.4-5.1 0.02-0.36
NI
100 0.7-7.0 2.0-5.4 3.3
11.8
0.9-3.0 1.0-4.7 0.3-1.5 0.5-3.0 0.6-2.9 0.9-3.1 0.4-12.3 0.3-3.8 0.2-2.0 0.5-4.5 ~1d-36.0~ 20 660 69
2.3-47.6 3.6-21.4 1.8-11.8 5.0-60.0 3.8-49.1 1.0-22.0 0.6-12.6 0.7-35.0
0.8-2.6 0.9-9.8 1.1-4.0 0.5-5.2
92
nd = not detected.
of detection. Corrected values for the metals studied are presented in Table 11. Sediments. Nearshore sediment samples were collected by hand, and deep water samples were taken with a bottom grab covered with epoxy paint to eliminate contamination. Each sample was washed, oven-dried at 100 "C, and ground in an agate mortar. The particles which passed through a 2 0 0 - ~ m (70 mesh) nylon sieve were analyzed. Samples for Cd, Pb, Cu, Zn, Ni, and Cr analysis were determined using the combined acid-reducing technique of Chester and Hughes ( 4 ) . The concentration measurements were taken on a Techtron AA-5 atomic absorption spectrophotometer. Fish. For the determination of the trace elements (Cd, Pb, Cu, Zn, Ni, and Cr), the homogenized fish tissue was ovendried a t 105 "C. The dry material was weighed in the Teflon vessel of the Uni-seal decomposition bomb, digested with concentrated nitric acid, and heated for 1 h at 130 "C. The cooled acid digest was evaporated to dryness, diluted to a standard volume (10 ml) with 0.1 M "03, and analyzed by AAS (Techtron AA-5). The advantage of bomb decomposition
is the rapid and complete digestion of the biological material, especially fatty matter. This was in contrast to the methods of Leonard ( 5 )and Anderson (6),tried by us, in which fatty matter caused difficulties. All analyses of water, sediments, and fish samples were done at least in duplicate, but most were done in triplicate. Blanks and standards were prepared in triplicate, using the same procedure as that for the samples. No significant interference from other ions was detected when samples of water, sediments, and fish were treated by spiking with standard solutions.
Results and Discussion Water. The preliminary results presented here illustrate the general levels found in the waters of the Israeli northern shore. The data show that only slight variations occur in the concentrations of lead, cadmium, copper, and nickel in the water, and most of the values are close to the overall mean given in Table 11. High values of Cd (2.0-2.9 ppb), Cu (22.1-31.2 ppb), P b (10.7-11.4 ppb), and Ni (5.0-5.4 ppb) found in the surface samples opposite densely populated
Table 111. Concentration (ppb) of Trace Metals in Water Samples of Three Coastal Stations (20 October-10 November 1974) Acre
20 Oct 21 Oct 22 Oct 23 Oct 25 Oct
Kiryat Yam
Haifa
Cd
Pb
Cu
Zn
Ni
Cd
Pb
Cu
Zn
Ni
Cd
Pb
Cu
Zn
NI
0.8 0.7 0.6 0.6 0.7
8.3 6.9 7.9 5.5 7.5
2.5 1.6 2.3 1.6 2.3
87.2 86.5 13.4 8.9 33.3
3.8 3.4 3.2 2.7 3.1
1.5 0.7 0.9 0.6 0.7
9.3 7.6 7.5 6.7 5.8
3.7 3.2 2.9 1.9 2.3
24.4 24.6 17.3 67.6 17.5
5.0 3.6 3.7 3.1 2.7
0.6 0.5 0.7 0.8 0.8 0.8
6.7 5.9 8.0 6.2 6.2 7.7
1.5 1.8 3.2 1.9 1.8 2.1
52.9 57.4 48.8 17.3 32.4 15.9
2.6 2.3 3.1 3.0 2.8 3.0
0.8 0.7 0.6 0.8 1.3
7.3 7.2 5.5 8.3 1.5
2.0 2.0 1.6 2.5 1.6
32.1 43.6 8.9 87.2 9.8
3.5 3.3 2.7 3.8 1.4
0.9 0.6 1.5 2.5
7.4 5.8 9.3 1.6
2.8 1.9 3.7 2.0
30.3 17.3 67.6 3.9
3.6 2.7 5.0 1.9
0.7 0.5 0.8 1.6
6.8 5.9 8.0 1.4
2.1 1.5 3.2 2.1
37.5 15.9 57.4 3.6
2.8 2.3 3.1 1.3
5 Nov 10 Nov
Mean Min
Max Maxmin
266
Environmental Science & Technology
.Table IV. Concentration of Heavy Metals in Particulate Matter in pg/l. (ppb) Cd
Sampling area
nd-OBa
Our data, range Our data, mean Clyde Bay (22) Trieste Bay ( 79)
0.2 0.01-0.06
cu
Zn
Ni
nd-2.1 0.4 0.4-4.4
0.4-24.2 5.7 0.2-1 1.2
nd-2.4 0.5
0.1-8.9
3.9-16.3
0.1-1.3
nd
Cr
nd-5.8 0.4
0.6-3.5
North Sea, shoreline (32) a
Pb
0.1-13.3 2.4
0.1-0.3
nd = not detected.
Table V. Concentration Range of Heavy Metals in Sediments from Various Marine Areas (ppm in Dry Sediment) Area
Cd
Present work, range Present work, average Israel coast, Tel-Aviv-Gaza (8) English coast, Southampton (27) English coast, Tor Bay (33) Cardigan Bay, Wales (34) Swansea Bay, Wales ( 3 9 Clyde Bay, Scotland (22) Clyde Estuary, Scotland (36) Atlantic Ocean (37) New York Bight (38) Harbor Island, Gulf of Mexico (39)
0.3-2.2 0.7 0.6-0.7 0.2-0.7 1.1 15 0.4-1.5 1.0-3.0
0.4-1.1
Pb
cu
3.9-19.7 8.4
0.3-2.9 1.6 1.4-24.2
21.3-65.7 25 195 12.0-45.0 24.0-67.0 16.0-35.0 12.0-25.0 3.4-9.0
2.4-7.6 11 75 2.7-17.1 9.0-20.0
2.1-18.2 7.0 5.4-49.6 115.0-224.0 17.2-42.0 36 170 34.0-102.0 60.0-130.0
Zn
Ni
3.0-8.0 2.7-5.2
18.0-26.0 14.0-28.0
Dry weight (%)
Cd
7.6 22.7 7.6 8.0
1.2 2.1 0.9 1.2
Cr
2.3-9.3 4.8 2.1-7.3
1.7-12.4 4.2 2.7-17.3
4.2-15.0
5.8-17.0
15.0-50.0 55 3 5.0-10.9
10.0-65.0 100 2.0-6.0
Table VI. Trace Metals in Marine Algae Location
Date (1974)
Acre (shore) Haifa (beach) Na’aman R. Estuary Nahariya (shore)
11 Jan 24 Jan 28 Jan 3 Jul
Algae
Chlorophyta Rhodophyta Chlorophyta Chlorophyta
settlements and in the vicinity of a chemical plant’s sewage outlet were exceptional. Considerable variations were found also for zinc, with high levels of 175.1-256.0 ppb in Haifa Bay. These high values of the trace elements could be attributed to the runoff from the two polluted rivers in this area. Comparison of sea areas in Table I1 confirms the general view that the water a t the shoreline, near densely populated and industrialized areas, contains higher levels of heavy metals than do coastal and ocean waters. Daily fluctuations of heavy metal concentrations were checked a t sampling stations along the shore of Haifa Bay between 20 October and 10 November 1974. The three stations chosen are close to the shore (10-20 m from the water’s edge), and hence were expected to be most affected by runoff. The data in Table I11 show that except for Zn, there were no significant daily fluctuations in the metal concentrations. Particulate Matter. With the exception of lead and zinc, heavy metals are found in solution rather than associated with particulate matter. The mean values obtained from all our data are close to the values found in Clyde Bay, Scotland, Trieste Bay, and the North Sea (Table IV). The high values of lead (5.8-13.3 ppb) and zinc (10.0-24.2 ppb) may have resulted from contamination or from organisms (retained on the filter pad) which concentrate these two elements (7). Sediments. The heavy metal concentrations in the sediments are presented together with data from other areas in Table V. A comparison of our results with those of Amiel and Navrot (8)shows that the concentrations of copper, zinc, and chromium along the southern shoreline are considerably higher than those obtained by us in the Haifa Bay area. The concentrations of nickel are the same for both areas. Most of the values for trace metal concentrations found in this study
Concentration (ppm dry weight) Pb Cu Zn Ni
5.6 22.2 1.9 5.3
2.9 7.6 5.5 5.4
218 117
5.2 5.8 5.3 5.5
Cr
No. of samples
6.7 2.6 2.8
5 3 3 3
are low when compared with values from other regions in the world. The present low levels of the trace metals in the nearshore sediments may represent an early stage in the accumulation of these elements, which may increase as pollution continues. The highest values of Cd (2.2 ppm), P b (19.7 ppm), Cu (2.9 ppm), Zn (18.2 ppm), Ni (9.3 ppm), and Cr (12.4 ppm) were found along the shores of Akhziv, Nahariya, and Acre. The presence of high concentrations could be explained by the proximity of domestic and industrial sewage outfalls. Trace elements in estuarine sediments are often much higher than those observed in sediments from the adjacent coastal areas (Clyde Bay-Clyde Estuary, Table V). Marine Algae. Only two species of algae were examined, Corallina uirgata (red algae, Rhodophyta), collected on the seashore near Haifa, and Codium tomentosum (green algae, Chlorophyta), collected a t the Na’aman Estuary, Nahariya, and Acre seashores. Both species are commonly found washed up on the beach and do not necessarily represent the dominant algae in the sea. The method applied for the determination of the metals was taken from Bernas (91,and the results are summarized in Table VI. The values obtained are useful only as a rough comparison with data in the literature. The ranges for Cd in marine algae found by Mullin and Riley ( I O ) (0.3-2.1 ppm dry weight) and levels for the other elements detected by Black and Mitchell (11) (Pb: 2.0-26.0, Cu:
