Pharmaceuticals, natural and synthetic hormones and phenols in sediments from an eutrophic estuary, Jurujuba Sound, Guanabara Bay, Brazil.

A screening for microcontaminants performed by gas chromatography detected several microcontaminants in 12 sediment samples from the eutrophic estuary Guanabara Bay (GB) in southeastern Brazil. Bisphenol A (BPA) ranged from 1.4 to 20.3 ng g-1, 4-octylphenol, from

Polycyclic aromatic hydrocarbons in sediments and shellfish from Todos os Santos bay, Brazil.

The present study evaluated the occurrence of 24 Polycyclic Aromatic Hydrocarbons (PAHs) in sediments and shellfish (Anomalocardia flexuosa, Crassostrea rhizophorae, and Mytella guyanensis) of Todos os Santos bay (BTS, Brazil). Total PAHs levels ranged from 89 to 921 ng g-1 dry weight (d.w.) in sediments, and from 66 to 505 ng g-1 d.w. in shellfish, signalizing that BTS was moderately contaminated by PAHs, mostly from pyrogenic activities. The bioaccumulation factor (BAF) of total PAHs ranged from 0.20 to 2.9 and did not show a clear trend among the studied species. BAFs of high molecular weight compounds were higher for A. flexuosa (specie found buried in fine sediment), while those of low molecular weight compounds were higher for C. rhizophorae (specie found in the roots of mangrove trees). High concentrations of PAHs, especially benzo[a]pyrene and dibenzo[a,h]anthracene, suggest that contamination compromises shellfish quality and raise concern about seafood consumption safety.

Oil spills: The invisible impact on the base of tropical marine food webs.

The Brazilian oil spill, from August 2019 to January 2020, was considered the most extensive accident in tropical oceans. We estimated the concentration of oil droplets that may be available for ingestion by microzooplankton. The collection was carried out in three areas: estuarine plume, bay and reef (Tamandaré, Pernambuco coast). We highlight the contribution of coral larvae in the reef region, surpassing the copepods, evidencing a spawning event. Oil droplets were recorded in all the sampled areas, with a high numerical abundance in the plume. Traces of oil ingestion by Brachyura zoea and Calanoida, Paracalanidae and Oithonidae copepods were observed, suggesting that these groups might have an important role in the degradation and final destination of oil dispersed after spills. The vulnerability of the larval phases of crabs and reef-building corals has been hypothesized, suggesting that the negative effects of oil on zooplankton can affect the recruitment of benthic invertebrates.

Additional Pressure to a Threatened Species: High Persistent Organic Pollutant Concentrations in the Tropical Estuarine Batoid Gymnura altavela.

Persistent organic pollutants (POPs) were determined in Gymnura altavela liver samples from one of the most impacted estuarine environments in the Atlantic Ocean (Guanabara Bay, Brazil). PCBs were the predominant compounds (91.2%) averaging 6773 ± 4659 ng.g-1 lipid weight (lw). DDT, Mirex, HCH and HCB concentrations were 633 ± 715, 6.2 ± 9.3, 3.4 ± 1.4 and 0.5 ± 0.5 ng.g-1 lw, respectively. Recent DDT input in the estuary was minimum, as verified by the p,p'-DDE/∑DDT ratio (0.67). The prevalence of industrial compounds was highlighted by the ΣDDT/ΣPCB ratio (0.08). A negative correlation detected between disc width and PCBs, Mirex and HCH concentrations may be a consequence of maternal offloading. High POP concentrations in G. altavela liver samples from Guanabara Bay suggests that PCBs, in particular, may pressure the conservation of this threatened with extinction tropical estuarine batoid species.

PCBs occurrence in marine bivalves and fish from Todos os Santos Bay, Bahia, Brazil.

In order to evaluate contamination by polychlorinated biphenyls (PCBs) in a tropical bay exposed to different anthropogenic pressures, samples of bivalves: mangrove oyster (Crassotrea rhizophorae), mangrove mussel (Mytella guyanensis)and clams (Anomalocardia brasiliana), were collected in different parts of Todos os Santos Bay, Bahia, Brazil. In addition, samples of bivalves and fish, purchased from a seafood market in the city of Salvador were analyzed to evaluate human exposure to PCBs through ingestion. Identification and quantification of PCBs were done by GC/MS after microwave extraction and purification with sulfuric acid. In bivalves, concentrations ranged from <0.08 to 50.1 ng g -1 (dry weight), with the highest values being detected in mangrove oyster, followed by clams and mangrove mussel of the Subaé estuary and Madre de Deus/Mataripe; regions known to be impacted by anthropic activities. From the total of the 12 fish species analyzed, only 5 presented levels of PCBs above the detection limit, ranging from 0.23 to 4.55 ng g -1 and 0.51 to 26.05 ng g -1 by dry weight and lipid weight, respectively. In general, concentrations of PCBs on the bay are lower than in most regions around the world, especially those located in the Northern Hemisphere. Indexes indicated that local biota and seafood from the fish market are not adversely impacted by PCBs and do not represent a risk to human health.

Concentration and distribution of polycyclic aromatic hydrocarbons in oysters from Todos os Santos Bay (Bahia, Brazil).

The aim of the present study was to evaluate the presence of polycyclic aromatic hydrocarbons (PAHs) in oysters (Crassostrea rhizophorae) collected from Todos os Santos Bay (Bahia, Brazil). The total PAH concentration was highest in Madre de Deus (36.3 to 37.8 ng g-1 in dry weight, dw), which is located near a petrochemical complex, oil refinery, and commercial port. In the Paraguaçu river estuary, PAH concentrations varied between 23.2 and 25.7 ng g-1 dw. The lowest concentrations (1.55 ng g-1 dw) were found in the Jaguaribe river estuary, which can be considered a relatively preserved area. The main source of PAHs in the study areas was observed to be pyrogenic. Values of benzo[a]pyrene toxic equivalent ranged from 0.28 to 4.20. The concentrations of PAHs in oysters from the Paraguaçu river estuary and in Madre de Deus indicate the possible lifetime risk of developing cancer in humans who feed on it.

Historical records of mercury deposition in dated sediment cores reveal the impacts of the legacy and present-day human activities in Todos os Santos Bay, Northeast Brazil.

We determined depth profiles of total mercury (T-Hg) in six 210Pb-dated sediment cores from Todos os Santos Bay to reconstruct the history of anthropogenic Hg accumulation. We also assessed superficial sediments samples from five estuaries. T-Hg concentrations (5-3500 µg kg-1) presented a large spatial and temporal variability. T-Hg concentrations in Ribeira Bay increased up to 200-fold along time, whereas the fluxes of T-Hg are substantially higher (up to 10,000 fold) than present-day wet deposition for industrialized areas. Sedimentary records indicate that a chlor-alkali plant has been the main source of Hg pollution until the present, although the T-Hg records suggest that harbor, shrimp farming, and oil refinery activities, besides Hg atmospheric depositions, are important across the bay. Sediments in the Ribeira Bay act as an important Hg sink. If sediments are eroded or disturbed, they may release Hg, thus posing a serious risk to wildlife and ecosystem health. CAPSULE: Sedimentary cores provide data on preindustrial levels and also anthropogenic fluxes of Hg for the appraisal of the magnitude, processes and potential risks of the contamination.

Metal bioaccumulation in edible target tissues of mullet (Mugil liza) from a tropical bay in Southeastern Brazil.

The present study aimed to investigate metal bioaccumulation in mullet (M. liza) from a tropical bay located in Southeastern Brazil, comparing a previously considered reference site to a known contaminated area of the bay, as well as to conduct human health risk assessments with regard to the consumption of this species. The metal concentrations were compared to the maximum residue level (MRL) in foods established by the different national and international regulatory agencies, and the Provisional Tolerable Daily Intake (PTDI) was determined and compared to reference values. Chromium (Cr), Zinc (Zn), Copper (Cu), Manganese (Mn), Nickel (Ni), Cadmium (Cd) and Lead (Pb) concentrations were determined in the gills, muscle and liver of 28 mullet by ICP-MS after acid digestion. Certain metals exceeded MRL guidelines established by different regulatory agencies, indicating human health risks associated to these metals. PTDI values, however, did not exceed corresponding metal values proposed by the World Health Organization. The metal concentrations found in the mullet samples indicate that the previously considered reference site is now showing signs of anthropogenic contamination.

Reproductive biology of Cetengraulis edentulus (Cuvier, 1829), the major fishery resource in Guanabara Bay, Brazil

Cetengraulis edentulus is a broadely distributed engraulid in Southwest Atlantic, currently accounting for the main fish species commercially exploited at Guanabara Bay, Brazil. This study aimed to extend the knowledge on reproduction of C. edentulus at Guanabara Bay and to test whether some descriptors of reproductive activity, especially the gonadosomatic index (GSI), and the index of reproductive activity (IRA) changed among seasons. A total of 978 C. edentulus specimens were retrieved from purse seine commercial landings at Conservas Rubi S.A. company, in São Gonçalo city, RJ. Subsamples of 90-120 individuals were collected from bimonthly yields between July 2010 (winter) and June 2011 (autumn). Most fish were adults (120-170 mm TL), in response to the high selectivity of commercial fisheries. All descriptors indicated a broad spawning period (late winter to spring), peaking in November, suggesting this is the critical period to protect C. edentulus stocks from overfishing at Guanabara Bay. Fecundity averaged 12,720 oocytes and was positively related to fish size, GSI and fullness index, indicating that preserving larger individuals (TL > 160 mm) could contribute significantly to the reproductive success of C. edentulus, since they produce more oocytes. Cetengraulis edentulus é um engraulídeo amplamente distribuído no Atlântico Sudoeste, sendo um importante recurso comercialmente explorado na baía de Guanabara, Brasil. O presente estudo teve como objetivo ampliar o conhecimento sobre a reprodução de C. edentulus na baía de Guanabara e testar quais descritores da atividade reprodutiva, especialmente o índice gonadossomático (IGS) e o índice de atividade reprodutiva (IAR) se modificaram ao longo das estações do ano. Um total de 978 indivíduos de C. edentulus foram capturados pelo método de rede de cerco da frota comercial no cais da empresa Conservas Rubi S.A., na cidade de São Gonçalo, RJ. Subamostras de 90-120 indivíduos de C. edentulus foram coletados bimestralmente durante o período de julho de 2010 (inverno) e junho de 2011 (outono). A maioria dos indivíduos foram adultos (120-170 mm CT), em resposta a alta seletividade das capturas comerciais. Todos os índices indicaram um amplo período reprodutivo (final do inverno e primavera), com pico em novembro, sugerindo que este seria um período crítico para preservar os estoques de C. edentulus da sobrepesca na baía de Guanabara. A fecundidade média foi de 12720 ovócitos e foi positivamente relacionada com tamanho do peixe, IGS e índice de repleção, indicando que preservar maiores indivíduos (CT > 160 mm) poderia contribuir significativamente para o sucesso reprodutivo de C. edentulus na área, visto que esses indivíduos produzem um maior número de ovócitos.

Reproductive biology of Cetengraulis edentulus (Cuvier, 1829), the major fishery resource in Guanabara Bay, Brazil

Cetengraulis edentulus is a broadely distributed engraulid in Southwest Atlantic, currently accounting for the main fish species commercially exploited at Guanabara Bay, Brazil. This study aimed to extend the knowledge on reproduction of C. edentulus at Guanabara Bay and to test whether some descriptors of reproductive activity, especially the gonadosomatic index (GSI), and the index of reproductive activity (IRA) changed among seasons. A total of 978 C. edentulus specimens were retrieved from purse seine commercial landings at Conservas Rubi S.A. company, in São Gonçalo city, RJ. Subsamples of 90-120 individuals were collected from bimonthly yields between July 2010 (winter) and June 2011 (autumn). Most fish were adults (120-170 mm TL), in response to the high selectivity of commercial fisheries. All descriptors indicated a broad spawning period (late winter to spring), peaking in November, suggesting this is the critical period to protect C. edentulus stocks from overfishing at Guanabara Bay. Fecundity averaged 12,720 oocytes and was positively related to fish size, GSI and fullness index, indicating that preserving larger individuals (TL > 160 mm) could contribute significantly to the reproductive success of C. edentulus, since they produce more oocytes. Cetengraulis edentulus é um engraulídeo amplamente distribuído no Atlântico Sudoeste, sendo um importante recurso comercialmente explorado na baía de Guanabara, Brasil. O presente estudo teve como objetivo ampliar o conhecimento sobre a reprodução de C. edentulus na baía de Guanabara e testar quais descritores da atividade reprodutiva, especialmente o índice gonadossomático (IGS) e o índice de atividade reprodutiva (IAR) se modificaram ao longo das estações do ano. Um total de 978 indivíduos de C. edentulus foram capturados pelo método de rede de cerco da frota comercial no cais da empresa Conservas Rubi S.A., na cidade de São Gonçalo, RJ. Subamostras de 90-120 indivíduos de C. edentulus foram coletados bimestralmente durante o período de julho de 2010 (inverno) e junho de 2011 (outono). A maioria dos indivíduos foram adultos (120-170 mm CT), em resposta a alta seletividade das capturas comerciais. Todos os índices indicaram um amplo período reprodutivo (final do inverno e primavera), com pico em novembro, sugerindo que este seria um período crítico para preservar os estoques de C. edentulus da sobrepesca na baía de Guanabara. A fecundidade média foi de 12720 ovócitos e foi positivamente relacionada com tamanho do peixe, IGS e índice de repleção, indicando que preservar maiores indivíduos (CT > 160 mm) poderia contribuir significativamente para o sucesso reprodutivo de C. edentulus na área, visto que esses indivíduos produzem um maior número de ovócitos.(AU)