TRACE METALS IN MUSCLE TISSUE FROM SOUTHERN BRAZILIAN COAST FISH.
Carvalho,C.E.V.;
Rezende,C.E.; Ferreira,A.G.; Faria,V.V.; Gomes, M.P. & Cavalcante, M.P.O. (Laboratório
de Ciências Ambientais, CBB, Universidade Estadual do Norte Fluminense, Av.
Alberto Lamego, 2000, Horto, Campos dos Goytacazes, R.J., CEP: 28015-620,
Brazil. Tel: +55 24 726-3709 Fax: +55 24 726-3720, E-mail: carvalho@cbb.uenf.br
).
As part of the Marine Environmental Monitoring Program (MoMAM) of the Brazilian Coast, fish samples were collected from five sites along the Southern Brazilian Coast. The present work reports the concentration of Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in fish species. Al and Cd presented the highest concentrations in Zapteryx brevirostris (158 and 7 mg.g-1d.w.) in Macaé and Barra de Guaratiba (respectively) both sites located in the coast of Rio de Janeiro State (RJ); Mn concentrated mainly in Porichthys porosissimus (7.7 mg.g-1 d.w.) from São Sebastião, São Paulo State (SP); Cr, Cu and Ni presented the highest concentration in Dasyatis guttata (0.5, 5.3 and 20 mg.g-1 d.w. respectively) from Atafona (RJ); Pb and Zn showed the highest concentration in Lophius gastrophysus (5,8 and 34 mg.g-1 d.w. respectively) from Arraial do Cabo (RJ); Fe concentrated mainly in Merluccius hubbsi and Prionotus punctatus (116 mg.g-1 d.w.) from Arraial do Cabo (RJ) and Ubatuba (SP). Most of the concentrations were close to that described at the literature for areas under low contamination impact.
Heavy metals generally are present in small amounts in
natural aquatic environments. Industrial activities have raised natural
concentrations causing serious environmental problems. The biota that inhabit
contaminated sites are generally exposed
to very high concentrations of these pollutants, and/or to distinct
chemical formula from the natural undisturbed ecosystems (Woo et al., 1993).
The
main pathway to human contamination by organic and inorganic pollutants
associated to aquatic systems is consumption of contaminated food (Mackay &
Clark, 1991). The potential risk to human health associated to the consumption
of contaminated food is 20 to 40 times higher than the ingestion of
contaminated water (Foran, 1990). This fact is due to the capacity of some
aquatic organisms to concentrate heavy metals up to 105 times the concentration present in the water
(Guimarães et al., 1985).
The sampling was performed on board of the research
vessel Batelão “Miguel dos Santos” from the Brazilian Navy. A total of four
samplings cruises were done in different areas, Macaé (M), Arraial do Cabo
(AC), Atafona (A), Barra de Guaratiba (BG), Baía de Guanabara (GB) and Parati
(P) in the Rio de Janeiro State and Ubatuba (U), São Sebastião (SS) and Santos
(S) in São Paulo State. The sampling was performed with an otter-trawl (10 meters large) in a 20 minutes drag, mesh
net was 1 cm.
Each sampled individual was identified following the
procedure described by Figueiredo (1977), Compagno & Springer (1978) and
Spilman (1992). All the samples were measured, weighted and reproductive
condition and sex was observed. All the samples were freeze in the ship to be
transported to the laboratory.
In
the laboratory 20 grams of muscle tissue was removed with the help of a
stainless steel surgery knife and oven dried (80°C/48h) and powdered in a
porcelain mortar. One gram of sample in triplicate was submitted to a strong
acid digestion (HCl + HNO3 conc. 3:1) in a glass tube block
digester. After complete dissolution the acid was evaporated to almost dryness
and dissolved in 0.5N HCl (Páez-Osuna, et
al., 1995). Metal determination (Al, Fe, Cd, Cr, Cu, Mn, Ni, Pb and Zn) was
performed with an ICP-AES (Varian, Liberty II), and the results expressed in mg.g-1 of dry
weight (dw).
The
metal average abundance observed in fish tissue was the following Al>Fe>Zn>Cd>Cu>Ni>Mn>Pb>Cr,
although the standard deviation was generally very high (table1). The high
standard deviation is probably due to the several biological and environmental
characteristics (e.g. metal essentiality, size, age, sex, feed habits, water
quality, distance from pollution source, etc) that will determine the
availability, intake and adsorption of the element by the local biota (Fostner
& Wittmann 1983).
Al
and Cd presented the highest
concentrations in Zapteryx brevirostris
(158 and 7 mg.g-1d.w.)
in Macaé and Barra de Guaratiba (respectively) located in the Rio de Janeiro
State (RJ); Mn concentrated mainly in Porichthys
porosissimus (7.7 mg.g-1
d.w.) from São Sebastião in São Paulo State (SP); Cr, Cu and Ni presented the
highest concentration in Dasyatis guttata
(0.5, 5.3 and 20 mg.g-1
d.w. respectively) from Atafona (RJ); Pb and
Zn showed the highest concentration
in Lophius gastrophysus (5,8 and 34 mg.g-1
d.w. respectively) from Arraial do Cabo (RJ); Fe concentrated mainly in Merluccius hubbsi and Prionotus punctatus (116 mg.g-1
d.w.) from Arraial do Cabo (RJ) and Ubatuba (SP).
It
is very important to mention that only Porichthys porosissimus
and Zapteryx brevirostris were collected in most of
all the sampling areas, this fact implies difficulties in comparing the sampled regions. Based on
heavy metal distribution in these two species it was possible to indicate some
of the areas that presented the highest metal concentrations. For Porichtys porosissimus the highest Al,
Cu and Mn concentrations were observed in the São Sebastião region (SP), Cd and
Zn were higher in the Rio de Janeiro Coast (station near Guanabara Bay), Fe
presented it's highest concentration in Ubatuba Region (SP) and Pb in the
Parati/Ubatuba region in the board from Rio and São Paulo States. For Zapteryx brevirostris the highest Zn, Pb and Ni
concentrations were observed in the Cabo Frio region (North of RJ State), Mn,
Fe and Cr were higher in the Parati/Ubatuba region and Cu and Cd higher at Rio
de Janeiro Coast (Baía de Guanabara and Barra de Guaratiba). Although the two
species did not show the same metallic distribution pattern, some of the above
mentioned areas presented high metal concentrations, showing that some
attention must be taken in order to avoid future metal contamination.
Comparing our results with previous works and literature
data it is possible to observe that although a large variability was observed,
the average of all studied fish presented values similar to the values
described by Pfeiffer et al. (1985)
in a study developed in Sepetiba Bay, in Rio de Janeiro State Coast.
Furthermore, the majority of the samples presented concentration below the
maximum permissible concentration determined by the Brazilian Health Ministry
(Table 1). It is important to mention that the study performed by Pffeifer
(1985) and the maximum permissible values determined by the BHM the concentrations are expressed in wet
weight. Considering that our values are in dry weight it is clear that our
results are lower than both studies.
Although
some of the studied areas presented strong human activities (e.g. Harbor,
contaminated river inputs, etc) the observed metal values in almost all samples
could be considered as unpolluted or with low levels of contamination.
Notwithstanding the fact that a minority of the samples presented high
concentration. This observation strengthen the importance of study the fish
biology and how it could influence the metal uptake, and also alarm the
authorities in order to begin to investigate coastal environmental
contamination.
References
Foran JA (1990). Environm. Sci. Technol. (24): 604-608.
Guimarães
JRD, Lacerda LD, Teixeira VL (1982), Rev. Brasil. Biol. 42: 553-557.
Mackay D, Clarck KE (1991), Predicting the environmental partitioning of organic contaminants and their transfer to biota. In: Jones KC (ed) Organic Contaminants in the Environment. Environm. Managem. Series, New York, Elsevier Science Pub.
Páez-Osuna
P, Frias-Espericueta MG, Osuna-López JI
(1995), Mar. Environ. Res. 40(17): 133-141.
Pfeiffer WC, Lacerda LD, Fiszman M, Lima NRW (1985), Ciênc. e Cult., 37 (2): 297-301.
Szpilman M (1992), Aqualung Guide of Fishes - A Practical Guide to The Identification of Brazilian Coastal Fishes. Aqualung Confecção Ltda.
Woo
P T K, Sin YM, & Wong MK (1993). Environ. Biol. of Fishes, 37: 67-74.
The
authors would like to express their gratitude to IEAPM (Project
Coordination), FENORTE and the
Brazilian Navy Ministry for financial and logistic support. The technicians
Arizoli A.R. Gobo, Cristina B. Siqueira, and Denise N. de Souza for the
laboratory support. The crew of the R.V. Batelão Miguel dos Santos. And M.Sc.
Eduardo Barros Fagundes Netto and M.Sc. Luiz Ricardo Gaelzer for species
identification. It is important to mention that this work is part of the Marine
Environmental Monitoring Program (MoMAM);that have the participation of the
following institutions: IEAPM, CTM, IO-USP, IRD, UFSC, UERJ, UFRJ and UENF.
Table 1. Average metal concentrations in all sampling sites in each of the
analyzed species (mg.g-1,
dry weight).
|
Species (sampling
areas) |
Al |
Cd |
Cr |
Cu |
Fe |
Mn |
Ni |
Pb |
Zn |
|
Myliobatis
freminuillei (AC) |
22.1 |
8.33 |
0.14 |
4.03 |
23.2 |
< 0.02 |
0.50 |
0.56 |
24.5 |
|
Zapteryx
brevirostris (M, GB, BG, AC, P, U) |
52.1 |
3.03 |
0.12 |
1.03 |
22.9 |
1.02 |
0.18 |
0.78 |
14.6 |
|
Psammobatis extenta (AC) |
99.0 |
2.49 |
< 0.01 |
1.40 |
24.0 |
< 0.02 |
0.66 |
2.77 |
17.3 |
|
Raja agassizi (M, AC) |
20.3 |
4.17 |
0.54 |
0.36 |
19.6 |
1.04 |
1.65 |
0.71 |
17.7 |
|
Raja castelnaui (AC) |
31.3 |
2.09 |
0.11 |
< 0.05 |
21.5 |
< 0.02 |
0.25 |
2.07 |
19.2 |
|
Raja sp (AC) |
2.4 |
2.42 |
0.42 |
< 0.05 |
1.00 |
< 0.02 |
0.70 |
1.70 |
11.8 |
|
Sympterigya acuta (M) |
4.1 |
2.48 |
< 0.01 |
0.91 |
1.00 |
< 0.02 |
< 0.03 |
< 0.05 |
19.1 |
|
Sympterigya
bonapartei (M) |
2.0 |
4.36 |
0.37 |
0.36 |
89.8 |
< 0.02 |
0.37 |
1.65 |
13.8 |
|
Dasyatis guttata (A) |
36.6 |
0.30 |
0.50 |
5.30 |
27.3 |
< 0.02 |
20.0 |
0.40 |
16.4 |
|
Pellona sp (A) |
109 |
0.10 |
0.40 |
3.40 |
67.6 |
< 0.02 |
< 0.03 |
0.10 |
15.4 |
|
Porichthys
porosissimus (GB, M, U, P, SS) |
24.0 |
0.65 |
0.14 |
0.40 |
34.9 |
1.67 |
< 0.03 |
< 0.05 |
17.6 |
|
Lophius
gastrophysus (AC, P, U ) |
71.0 |
0.69 |
1.15 |
1.02 |
49.8 |
1.86 |
0.73 |
2.28 |
26.1 |
|
Merluccius hubbsi (AC) |
52.1 |
10.7 |
1.00 |
1.28 |
75.2 |
1.87 |
0.37 |
1.57 |
19.0 |
|
Prionotus punctatus (U, P, A) |
54.0 |
0.06 |
0.27 |
1.85 |
66.3 |
1.07 |
< 0.03 |
0.47 |
17.0 |
|
Dules auriga (P, U) |
19.7 |
0.15 |
0.10 |
0.40 |
38.1 |
1.21 |
< 0.03 |
0.07 |
17.7 |
|
Conodon nobilis (A) |
156 |
0.00 |
0.26 |
3.46 |
75.4 |
< 0.02 |
2.30 |
0.51 |
16.2 |
|
Pagrus pagrus (P,U) |
21.4 |
0.46 |
< 0.01 |
0.30 |
21.7 |
0.36 |
< 0.03 |
0.09 |
11.1 |
|
Cynoscion sp (M) |
29.0 |
< 0.02 |
< 0.01 |
0.81 |
18.0 |
< 0.02 |
< 0.03 |
< 0.05 |
10.7 |
|
Macrodon ancylodon (M) |
27.0 |
< 0.02 |
< 0.01 |
0.76 |
16.2 |
< 0.02 |
< 0.03 |
< 0.05 |
8.69 |
|
Menticirrhus
littoralis (M) |
20.0 |
< 0.02 |
< 0.01 |
0.58 |
8.80 |
< 0.02 |
< 0.03 |
< 0.05 |
8.53 |
|
Micropogonias
furnieri (U) |
23.6 |
0.18 |
< 0.01 |
0.50 |
21.8 |
1.40 |
< 0.03 |
0.23 |
12.6 |
|
Ophioscion
punctatissimus (M) |
34.0 |
< 0.02 |
< 0.01 |
0.85 |
12.8 |
< 0.02 |
< 0.03 |
< 0.05 |
9.88 |
Stellifer rastrifer (M, A)Paralichthys
patagonicus (P,U, SS, S) |
94.8 17.2 |
0.06 0.28 |
0.42 0.17 |
1.91 0.19 |
49.5 32.8 |
< 0.02 2.14 |
< 0.03 < 0.03 |
0.05 0.08 |
11.1 11.1 |
|
Symphurus trewavasae
(U) |
21.4 |
0.29 |
0.08 |
0.41 |
26.2 |
0.68 |
< 0.03 |
< 0.05 |
15.1 |
|
Symphurus sp (M) |
47.0 |
< 0.02 |
< 0.01 |
0.63 |
31.7 |
< 0.02 |
< 0.03 |
< 0.05 |
13.6 |
|
Paralonchurus
brasiliensis (S, A, M) |
61.3 |
0.13 |
0.35 |
1.59 |
34.7 |
0.69 |
< 0.03 |
0.41 |
11.4 |
|
Syacium sp (S) |
26.8 |
0.19 |
0.27 |
0.25 |
23.6 |
2.50 |
< 0.03 |
0.07 |
13.9 |
|
Pfeifer et
al. 1985 (wet weight) |
- |
0.03 |
0.53 |
0.53 |
- |
0.65 |
- |
0.93 |
11.8 |
|
Maximum Permissible BHM (wet weight) |
- |
1.0 |
0.1 |
30 |
- |
- |
- |
8.00 |
100 |
|
Average |
44.1 |
1.46 |
0.33 |
1.29 |
35.0 |
0.92 |
1.17 |
0.61 |
15.0 |
|
Standard deviation |
38.3 |
2.51 |
0.28 |
1.33 |
26.2 |
0.66 |
3.96 |
0.75 |
4.82 |
Sampling sites along Rio de Janeiro State: Atafona (A); Arraial do Cabo (AC); Macaé (M); Parati(P); Baía de Guanabara (GB); Barra de Guaratiba (BG). Sampling sites in São Paulo State: Ubatuba (U); São Sebastião (SS) and Santos (S).