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Freitas, A.S.; Pompermayer, L.L.O.; Santos, A.D.O.; Nascimento, M.T.L.; Félix, L.C.; Bila, D.M.; Neto, J.A.B., and Fonseca, E.M., 2024. Sediment toxicity assessment using marine organism bioassays from an urban coastal lagoon (Padre Lagoon, southeastern Brazil). Journal of Coastal Research, 40(2), 278–288. Charlotte (North Carolina), ISSN 0749-0208. This study aimed to evaluate the environmental quality of Padre Lagoon, an urban coastal lagoon, by using ecotoxicological fossil organisms (dinoflagellate cysts) for biomarker analysis associated with 14C radiocarbon dating. This is the first toxicity study in this anthropogenic coastal lagoon. A total of 15 surface sediment samples and a sediment core were analysed by radiocarbon dating, grain size, dinoflagellate cysts, and acute toxicity bioassays to assess the influence of land use changes in accelerated urban development in recent decades. Sediments varied between coarse sand and mud at different proportions. Radiocarbon dating placed the oldest age at 470–314 calibrated YBP in the sediment core base according to 14C radiocarbon dating. Artemia sp. showed high toxicity in both surface and core sediment samples. Vibrio fischeri showed a toxicity gradient in the sediment core and high toxicity in several surface samples. A major dinoflagellate cyst occurrence was observed in the sediment core; however, the highest accumulation was observed in the surface sediments. The data obtained in this study revealed high toxicity in the analysed sediment samples and the need for greater monitoring of this coastal lagoon. [ABSTRACT FROM AUTHOR]

Compounds displaying estrogenic potential can lead to serious negative aquatic ecosystem impacts, and exposure to mixtures of endocrine disruptors present in environmental matrices with very complex characteristics, including sediments, can cause serious risks to biota, animals, and humans. Within this perspective, the aim of the present study was to assess estrogenic activity and toxicity in sediments sampled from Guanabara Bay, the most important, although chronically polluted, estuary in southeastern Brazil. To this end, estrogenic activity determinations were performed by the yeast estrogen screen (YES) assay, and acute toxicity assays were carried out employing Vibrio fischeri. Estrogenic activity was quantified up for 8.7 ng g−1 in E2‐EQ, although high levels of cytotoxicity (up to 95%) were observed and might have hindered the determination of the real estrogenic potential in most samples. Acute toxicity to V. fischeri ranged from 0 to 45.21%. These results point to potential deleterious effects caused by micropollutants and underline the urgency of continuous monitoring of the degradation degree of the Guanabara Bay estuary. [ABSTRACT FROM AUTHOR]

Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to examine the water quality of the Extrema River spring in a Brazilian Cerrado area. Three collection sites (P1 - P3) were sampled in the dry and rainy seasons, which are close to industries from different sectors. In the physicochemical analysis, a decrease in dissolved oxygen levels (<5 mg/L) and pH (< 6) at P3 was detected. An increase in heterotrophic bacteria count was recorded at all sites (> 500 colonies/ml). In ecotoxicological analyses, P2 and P3 exhibited toxicity using Vibrio fischeri (> 20%). In evaluating toxicity, the reduction in seed germination was significant utilizing Lactuca sativa at all locations and with Allium cepa only at P2; rootlet length was decreased at P3 on L. sativa and at all sites with A. cepa. In contrast, loss of membrane integrity and mitochondrial function of meristems was adversely affected at all locations using both L. sativa and A. cepa assays. Principal components analysis (PCA) approach indicated that seasonality apparently did not markedly interfere with the obtained data, but it is important to include more collection locations to be evaluated with multiple bioindicators in the spring region. Our data indicate the urgent need for more rigorous programs to monitor the discharge of effluents into water springs.

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Harbours are located in major urban centres around the world and are of great economic importance to the cities in their surroundings. However, the intense traffic of boats and ships can generate environmental impacts that can directly affect the local biota as well as the population that lives in surrounding areas. Therefore, this work aimed to analyse the surface sediment of the Niterói Harbour using chemical, biological and micropalaeontological tools to investigate the environmental condition of this important harbour in Rio de Janeiro State. The pseudototal trace metal data analysed in the surface samples showed values far above those of the greater Guanabara Bay background. These data were corroborated by a high mortality rate of Artemia sp. and elevated presence of the bacterium Vibrio fischeri , indicating a high rate of local pollution. Dinoflagellate cysts also showed a direct response to high values of pseudototal trace metals. The data obtained in this study emphasize a need for greater monitoring of ports since the experience gained through this study in a Brazilian harbour can serve as an example for the management of other harbours located in large urban centres around the world. • Chemical pollutants in surface sediments from Niterói harbour, Brazil • Dinoflagellate cysts, Vibrio fischeri and Artemia sp. as a biomonitoring tool • Pb and Cd as potential pollutants affecting the biota and population surrounding [ABSTRACT FROM AUTHOR]