Mercury Concentrations in Two Populations of the most Endangered Dolphin (Pontoporia blainvillei) from the Southwestern Atlantic Ocean.

Mercury contamination has been aggravated by emerging environmental issues, such as climate change. Top predators present concerning Hg concentrations once this metal bioaccumulates and biomagnifies. This study evaluated total mercury (THg) concentrations in tissues of 43 franciscanas (Pontoporia blainvillei) from two populations: the Franciscana Management Area (FMA) IIb and FMA IIIa.

The amphipod Parhyale hawaiensis as a promising model in ecotoxicology.

Near-shore marine/estuarine environments play an important role in the functioning of the marine ecosystem and are extremely vulnerable to the presence of chemical pollution. The ability to investigate the effects of pollution is limited by a lack of model organisms for which sufficient ecotoxicological information is available, and this is particularly true for tropical regions. The circumtropical marine amphipod Parhyale hawaiensis has become an important model organism in various disciplines, and here we summarize the scientific literature regarding the emergence of this model within ecotoxicology.

Measuring concentrations of a dye in the hemolymph of a marine amphipod: Development of a protocol for exposure assessment.

The increasing pollution of aquatic environments due to old and emerging contaminants requires the development of integrative methods for exposure assessment. Internal concentrations are a reliable way to estimate total exposure of contaminants originated from different routes (water, sediment, and food). We developed a protocol to evaluate the concentration of a dye, C.

Unusual male size vs sperm count relationships in a coastal marine amphipod indicate reproductive impairment by unknown toxicants.

Sperm quantity/quality are significant reproductive endpoints with clear links to population level dynamics. Amphipods are important model organisms in environmental toxicology. Despite this, field monitoring of male fertility in invertebrates has rarely been used in monitoring programs.

Pyrethroid insecticides along the Southwestern Atlantic coast: Guiana dolphin (Sotalia guianensis) as a bioindicator.

The presence of pyrethroid compounds in hepatic tissue of Guiana dolphins (Sotalia guianensis) is reported for the first time. Twelve pyrethroids were determined in 50 animals from eight locations of the Brazilian coast. The highest average concentration of total pyrethroids (∑PYR) was 1166 ng.

Behavioural effects on marine amphipods exposed to silver ions and silver nanoparticles.

Behavioural responses to contaminants are an important endpoint in ecotoxicology because they link effects at biochemical or cellular levels to impacts on individual fitness. Due to the increasing use of silver in nanomaterials, studies of its effects on the behaviour of aquatic organisms are important to assess the risks of silver nanoparticles (AgNP) released into the environment. The aim of this work was to evaluate the behavioural effects of silver on the marine amphipod Echinogammarus marinus after exposure to AgNO via water and AgCl or AgNP via food.

Higher silver bioavailability after nanoparticle dietary exposure in marine amphipods.

On release into surface waters, engineered silver nanoparticles (AgNPs) tend to settle to sediments and, consequently, epibenthic fauna will be exposed to them through diet. We established Ag uptake and accumulation profiles over time in the hemolymph of a marine amphipod fed with a formulated feed containing AgNPs or AgCl. Silver bioavailability was higher in organisms exposed to AgNPs, indicating that the nanoparticles pose a higher risk of toxicity compared to similar concentrations of AgCl.

Speciation of lead in seawater and river water by using Saccharomyces cerevisiae immobilized in agarose gel as a binding agent in the diffusive gradients in thin films technique.

Saccharomyces cerevisiae immobilized in agarose gel is proposed as a binding agent for the diffusive gradients in thin films (DGT) technique for determination of Pb in river water and seawater. DGT samplers were assembled with the proposed binding agent (25-mm disk containing 20%, m/v, S. cerevisiae and 3.