BIODISPONIBILIDADE E TOXICIDADE DE CONTAMINANTES EM SEDIMENTOS NA PORÇÃO NORDESTE DA BAÍA DE TODOS OS SANTOS
Hidrocarbonetos
Toxicologia
Bentos
Tríade BTS
Hidrocarbon
Toxicology, Bentos, Triad TSB
CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOLOGIA::GEOQUIMICA
Resumo
The purpose of this study the quality of the sediment surface of the northeast portion of the
Todos os Santos Bay through the application of the sediment quality triad. For samples that
were collected from surface sediment samples in eight seasons (Coqueiro Grande (1-CG),
Mataripe (2-MA, 3-MA, 4-MA, 5-MA), Caípe (6-CA), Suape (7-SU) e Coqueiro Grande (8-
CG)) in the northern portion of the Todos os Santos Bay-BA, (TSB). It was determined the
spatial distribution of acid volaties sulfides (AVS) and simultaneously extracted metal (SEM)-
(Cd, Cu, Pb, Ni and Zn), nutrients (C.O, Ntotal), TPH and PAH by GC/MS. They also
evaluated the size, pH and Eh of the sediment. The AVS was extracted from the anaerobic
sediment with hydrochloric acid 1 mol L-1, the cold, and the divalent metals released during
this treatment are referred to as simultaneously extracted metals (SEM). The method of
hydrocarbons followed USEPA. The tests were performed Ecotoxicological sediments with
benthic copepods Tisbe biminiensis. Samples of macrozoobentos were collected, counted and
identified to the level taxonomic family. Tests showed statistical difference between the
stations. The results obtained by reason AVS/SEM, were correlated with the size fractions,
total organic carbon (0.14 11.6%), total nitrogen (0.02 0.25%), metals [Cd (<0.10 0.26
μg g-1), Cu (0.04 35.42 μg g-1), Pb (0.02 9.85 μg g-1), Ni (<0.07 4.76 μg g-1), Zn (16.74
38.39 μg g-1)]. Compared to the results with international reference values (National
Oceanic and Atmosferic Administration - NOAA and Summary of Existing Canadian
Environmental Quality Guidelines) it was found to be below the set, when even compared
with those found in other regions of Brazil. There was still, values <1 for the ratio [SEM] /
[AVS], not suggesting the bioavailability of these metals, except in stations 1-CG, 2-MA, 5-
MA- and 7SU (1st collection) and 1-CG (2nd collection). The results ecotoxicological test
with the Tisbe biminiensis had sub-lethal effects in the CG-stations, 2-MA, 5-MA and 7 -SU
(1st collection). The screening resulted in a total of 1333 bodies belonging to only 6 phylo.
The groups of highest species richness were Mollusca (12), the Annelida - Polychaeta (8),
beyond the Arthropoda - Crustacea (6), which accounted for 97.8% of taxonomic unit
sampled. It was found that the stations located in spite of not showing mesolitoral values of
density, richness and diversity much higher than the stations located in infralitoral show a
distinct pattern of distribution with dominance of polychaetes specifies indicators of organic
contamination as Capitellidae. The bivalve (Anomalocardia brasiliana, Tellina sp., Tagelus
plebeius) and polychaetes (Capitella sp., Laeonereis acuta, Glycinde multidens) were the
most representative species. The richness of species, relatively low, observed in the study
area, may be related to the occurrence of the high percentage of mud, which has been
described by previous work that the associations are faunistic poorest. The integration of the
Triad using the table for a decision to classify the area into 4 categories: 1st collection: high
quality (8-GC), intermediate/high quality (3-MA), intermediate/degraded quality (6-CA, 5-
MA and 7-SU), degraded quality (1-CG, 2-MA and 4-MA). In the 2nd collection: high quality
(5-MA, 6-CA and 7-SU), intermediate/high quality (2-MA, 3-MA and 8-GC),
intermediate/degraded quality (4-MA), degraded quality (1-GC). The results of this study
suggest that the quality of the sediment infralitoral (1-CG, 2-MA e 4-MA) have more
evidence of degradation induced by contamination of the stations of mesolitoral.
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Assunto(s)
MetaisHidrocarbonetos
Toxicologia
Bentos
Tríade BTS
Hidrocarbon
Toxicology, Bentos, Triad TSB
CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOLOGIA::GEOQUIMICA