The objective was to determine the spatial-temporal distribution of total mercury (T-Hg) bioavailability at the Goiana Estuary using Anomalocardia brasiliana as model organism. Two seasons (rainy in February and dry in August), three habitats of the tidal flats (upper, middle and lower) and two size classes (<20 mm and >20 mm) were considered. In addition, depurated and non-depurated samples were tested. Individuals (N = 600) were pooled in samples representing the combinations of the above situations. T-Hg in the tissues of the pooled samples of A. brasiliana from Goiana Estuary varied from 0.06 and 0.18 μg g-1 dry weight. Significant differences occurred between treatments (P < 0.05). In average (10-30%), after depuration T-Hg concentrations decreased, especially at the tidal flat areas most exposed to tidal variations (upper and middle). There were no significant differences between seasons or size classes.

El objetivo del estudio fue determinar la distribución espacio-temporal de la biodisponibilidad de mercurio total (T-Hg) en Anomalocardia brasiliana como organismo modelo en el estuario de Goiana. Se efectuaron observaciones en dos temporadas (lluvia febrero y sequía en agosto), en tres habitats, en llanuras de marea (alta, media y baja) y se consideraron dos clases de tamaño (<20 mm y >20 mm). Además, se utilizaron muestras depuradas y no depuradas. Los individuos (N = 600) se agruparon en las muestras que representan las combinaciones de las situaciones anteriores. T-Hg en los tejidos de las muestras combinadas de A. brasiliana variaron entre 0,06 y 0,18 μg g-1 peso seco. Diferencias significativas se produjeron entre tratamientos (P < 0,05). En promedio (10-30%), después de las depuraciones de concentraciones de T-Hg disminuyeron, especialmente en las áreas planas de marea más expuesta a las variaciones de marea (alta y media). No hubo diferencias significativas entre estaciones y clases de tamaño.

The study assessed selenium concentrations in the muscle tissues and liver samples of three fish species and in the soft tissues of a mussel species. The samples were analyzed by GF-AAS using Zeeman background correction. Selenium in the muscle samples was higher in carnivorous fish. The liver of all studied fish species presented higher selenium concentrations than the muscle. The fish species presented a high positive correlation between their total length and selenium concentration. A significant correlation was observed between the selenium concentration in the mussel soft tissues and the condition index.