Trace elements influence the hatching success and emergence of Caretta caretta and Chelonia mydas.

Trace elements from industrial, domestic and agricultural activities can be transferred into marine environments, affecting the survival of sea species. Due to their global distribution, sea turtles are recognized as indicators of ocean pollution. The aim of this work was to quantify Ba, Cd, Cr, Cu, Fe, Mn, Pb, Sr and Zn using inductively coupled plasma optical emission spectrometry (ICP-OES) in the eggs and offspring of Caretta caretta and Chelonia mydas from two important nesting beaches, Guanabara Beach, Anchieta, and Trindade/Martim Vaz Island, Espírito Santo, Brazil. C. mydas pups and eggs collected on Trindade/Martim Vaz Island presented significant differences in Ba, Cr, Cu, Mn and Sr (p < 0.001). Higher concentrations of Ba, Pb, and Sr were detected in eggs of this species in comparison to those of C. caretta on Guanabara Beach, Anchieta. Ba and Cd presented higher concentrations in pups than in eggs of C. caretta, which could indicate nesting pollution. Positive correlations between trace element concentrations and hatching success in C. caretta nests from Guanabara Beach, Anchieta, could be identified for Cu and Zn (r²â€¯= 0.86, F2.7 = 21, p < 0.001). Emergence success was influenced by Cu and Cd (r²â€¯= 0.84, F2.7 = 18.9, p = 0.002). In addition, Ba and Cd also influenced the emergence sucess (r²â€¯= 0.56, F2, 10 = 6.29, p = 0.017). The hatching success of C. mydas was influenced by the concentration of Cu (r²â€¯= 0.53, F2.14 = 7.82, p = 0.005). Further studies including the analyzed areas and migratory routes should be performed to promote conservation management at these beaches.

High waterborne Mg does not attenuate the toxic effects of Fe, Mn, and Ba on Na+ regulation of Amazonian armored catfish tamoatá (Hoplosternum litoralle).

Formation water (FoW) is a by-product from oil and gas production and usually has high concentrations of soluble salts and metals. Calcium (Ca) and magnesium (Mg) have been shown to reduce the toxicity of metals to aquatic animals, and previous study showed that high waterborne Ca exerts mild effect against disturbances on Na+ regulation in Amazonian armored catfish tamoatá (Hoplosternum littorale) acutely exposed to high Fe, Mn, and Ba levels. Here, we hypothesized that high Mg levels might also reduce the toxic effects of these metals on Na+ regulation of tamoatá. The exposure to 5% FoW promoted an increase in Na+ uptake and a rapid accumulation of Na+ in all tissues analyzed (kidney

Development of the concept of spatial-temporal mask for testing effects of discharge from well-drilling activities on biological communities.

This paper describes the use of Bayesian spatial models to develop the concept of a spatial-temporal mask for the purpose of identifying regions in which before and after drilling effects are most clearly defined and from which the consequences of exposure of macrofauna and meiofauna to the release of drilling discharges can be evaluated over time. To determine the effects of drilling fluids and drill-cuttings on the marine benthic community, it is essential to know not only where discharged materials ended up within the possible impact area, but also the chemical concentrations to which biota were exposed during and after drilling. Barium and light hydrocarbons were used as chemical tracers for water-based and non-aqueous-based fluids in a shallow water site in the Campos Basin, off the coast of Brazil. Since the site showed evidence of exposure to waste material from earlier drilling, the analysis needed to take into account the background concentrations of these compounds. Using the Bayesian models, concentrations at unsampled sites were predicted and regions altered and previously contaminated were identified.

Toxicologia experimental de compostos contendo bário solúvel

Embora aparentemente incipiente, compostos contendo Bário podem induzir quadro de intoxicaçäo pouco estudados. Envenenamentos têm ocorrido em animais, pela ingestäo de inseticidas inôrganicos `a base de bário (Bartic & Pistak, 1981). No homem eles ocorrem por penetraçäo intrapulmonar de Sulfato de Bário, por ingestäo de Cloreto de Bário, ou por inalaçäo habitual de resíduos anemófilos contendo Bário, advindos da soldadura de metais (Caldas et al., 1984). Na presente investigaçäo tenta-se simular em três grupos de experimentos, os agentes causais e efeitos capazes de induzir alteraçöes na fisiologia de cobaios: 1) Efeitos in vivo, de doses (4 -12 mg/Kg) de Cloreto de Bário (BaCl2) e de extrato de resíduos metálicos ricos em bário solúvel (BaF); 2) Efeitos in vitro, de BaCl2, e BaF em músculo liso de cobaio; e 3) o uso de propranolol e Nifedipina nos experimentos citados. In vivo, observam-se: efeitos brancoconstritores, nas aplicaçöes por aerosol ou por via venosa; arritmias cardíacas, com inversäo de onda T; e complexos QRS bizarros e extrassístoles, com elevaçäo da pressäo arterial. In vitro, ielo isolado e segmentos de parenquima pulmonar e traquéia, mostraram respostas contráteis de longo curso, com menores potência e eficácia do que as da histamina e acetilcolina. In vivo e in vitro os efeitos foram antagonizados pela nifedipina (10-6-10-9M). In vivo, propranolol (4 mg/Kg) bloqueou parte dos efeitos pressores do bário, e ecentuou as arritmias cardíacas. Conclui-se que uma exposiçäo continuada, a compostos de bário solúvel, constitui perigo potencial para os sistemas respiratório e cardiovascular. E, ainda, que o uso Nifedipina previniria os efeitos nocivos, enquanto que Propranolol seria contra-indicado