RESUMEN
The Brazilian sardine (Sardinella aurita) is an important food resource found in the subtropical Southwestern Atlantic Continental Shelf (CSSWA), but limited information about its metal(loid) concentrations is available, restricting effective risk assessment by its consumption. On this research, we hypothesized that S. aurita presents different metal(loid) concentrations within a latitudinal gradient in the CSSWA (northern and southern sectors). We also assessed the S. aurita consumption contamination risk in both sectors of the CSSWA. The results indicated that S. aurita might present different chemical and contamination profiles between the observed sectors, with highlights to As, Cr, and Fe at greater levels than the safety limits established by regulatory agencies. Such finds could be explained by urbanization, industrialization, continental and oceanographic processes along the CSSWA, corroborating our hypothesis for most observed metals(loid). On the other hand, our risk assessment analysis of metal(loid) concentrations did not indicate hazards for human consumption.
Asunto(s)
Metales Pesados , Contaminantes del Suelo , Animales , Humanos , Monitoreo del Ambiente/métodos , Brasil , Metales/análisis , Alimentos Marinos/análisis , Peces , Medición de Riesgo , Metales Pesados/análisis , China , Contaminantes del Suelo/análisisRESUMEN
Concentrations of PAHs and metals were obtained from mussels collected in beaches, coastal island and estuary of the Macaé coast, the main operational basin for offshore oil exploration in Brazil. This survey provides reference levels for scenarios of increasing exploration, as well as for other areas of the coast undergoing urbanization to support exploration. As expected, urban areas such as the Macaé river estuary presented high concentrations of PAHs, although unsuspected sites such the island also presented signs of contamination. PAH in mussels originated from pyrolytic and petrogenic sources. Metals were typical of non-contaminated coastal environments, although Cr concentrations were above Brazilian Reference Levels.
Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Yacimiento de Petróleo y Gas , Perna/química , Hidrocarburos Policíclicos Aromáticos/análisis , Ríos/química , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Brasil , Estuarios , Sedimentos Geológicos/químicaRESUMEN
Dissolved gaseous Hg, reactive Hg, total dissolved Hg and particulate Hg concentrations were measured in samples of majors tributaries of the Sepetiba Bay, SE Brazil (Itimirim, Itinguçu, Guarda, Guandu, São Francisco and Ita rivers), in dry and rainy seasons. The average Hg concentrations found varied from 0.02 to 0.18 ng L(-1) for dissolved gaseous Hg, from 0.1 to 18.1 ng L(-1) for reactive Hg, from 0.1 to 66.6 ng L(-1) for total dissolved Hg and from 0.3 to 250 ng L(-1) for particulate Hg. During the rainy season, a decrease in the dissolved Hg concentrations and an increase in the particulate Hg concentrations was observed. Positive correlations were found between the reactive Hg and the total dissolved Hg concentrations (r = 0.99), between the particulate Hg and TSS concentrations (r = 0.82) and between total Hg and particulate Hg concentrations (r = 0.95). The instantaneous Hg fluxes varied among rivers from 0.02 to 412 microgs(-1) for total dissolved Hg and from 0.03 to 12,572 microgs(-1) for particulate Hg. The log Kd varied from 3.76 to 6.43 and showed a significant increase in rainy season following an increase in particulate Hg and a decrease in dissolved Hg concentrations. These results suggest that erosion and runoff are the major pathways of Hg transport to rivers and eventually to Sepetiba Bay.