Biochemical and histopathological responses in Nile tilapia exposed to a commercial insecticide mixture containing dinotefuran and lambda-cyhalothrin.

The indiscriminate use of pesticides has led to an increased risk of environmental contamination and pest resistance worldwide, favoring the development of less hazardous formulations. The commercial insecticide ZEUS® (Ihara, Brazil) combining dinotefuran and lambda-cyhalothrin was recently formulated in order to meet the environmental sustainability and food security. However, little is known about the potential toxic effects of ZEUS® to aquatic species.

Response of biomarkers to metals, hydrocarbons and organochlorine pesticides contamination in crabs (Callinectes ornatus and C. bocourti) from two tropical estuaries (São José and São Marcos bays) of the Maranhão State (northeastern Brazil).

Response of biomarkers to chemical contamination was evaluated in crabs of the Callinectes genus (Callinectes ornatus and C. bocourti) from two tropical estuaries (São José and São Marcos bays) of the Maranhão State (northeastern Brazil). Biomarkers evaluated included hepatopancreatic metallothionein-like proteins (MTLP) and lipid peroxidation (LPO), as well as muscle acetylcholinesterase (AChE).

The bioaccumulation of waterborne zinc in tissues of silver catfish (Rhamdia quelen) and its effect on biochemical parameters.

Silver catfish (Rhamdia quelen) is a fish species with neotropical distribution, and is a potential model organism to study polluted environment. The aim of this study is to analyze the response of silver catfish to environmental concentrations of waterborne zinc (Zn) over 96 h. Significant metal accumulation was seen in gill, intestine and liver tissues.

Selection of biochemical and physiological parameters in the croaker Micropogonias furnieri as biomarkers of chemical contamination in estuaries using a generalized additive model (GAM).

Biochemical and physiological parameters in the croaker Micropogonias furnieri were evaluated as biomarkers of chemical contaminants in estuaries. Juvenile croakers (10-20 cm total body length) were collected in summer and winter (2011 and 2012), in two sites at the Lagoa dos Patos estuary (southern Brazil). Fish were also collected in summer (2011 and 2012) in one site at the Barra do Chui estuary (southern Brazil).

Effects of Experimental Lead Exposure on Testis of the Chestnut Capped Blackbird Chrysomus ruficapillus.

Lead (Pb) effects on testis histology, as well as sperm quality and oxidative status were evaluated in male Chestnut Capped Blackbird (Chrysomus ruficapillus). Wild blackbirds were captured, immediately sampled (field group) or kept in captivity and treated with a single intraperitoneal injection of saline solution (control) or saline solution with Pb acetate (50 or 100 mg/kg Pb). Seven days after injection, whole blood, ductus deferens and testis samples were collected.

Genetic and biochemical effects induced by iron ore, Fe and Mn exposure in tadpoles of the bullfrog Lithobates catesbeianus.

For decades, the extraction of minerals has intensified in order to meet the demand of industry. Iron ore deposits are important sources of metals, such as iron (Fe) and manganese (Mn). The particulate ores can be dispersed during extraction, transport and storage, with potential to induce biological impacts.

Metal contamination as a possible etiology of fibropapillomatosis in juvenile female green sea turtles Chelonia mydas from the southern Atlantic Ocean.

Environmental contaminants have been suggested as a possible cause of fibropapillomatosis (FP) in green sea turtles. In turn, a reduced concentration of serum cholesterol has been indicated as a reliable biomarker of malignancy in vertebrates, including marine turtles. In the present study, metal (Ag, Cd, Cu, Fe, Ni, Pb and Zn) concentrations, oxidative stress parameters [antioxidant capacity against peroxyl radicals (ACAP), protein carbonyls (PC), lipid peroxidation (LPO), frequency of micronucleated cells (FMC)], water content, cholesterol concentration and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) activity were analyzed in the blood/serum of juvenile (29.

Concentrations and distributions of metals in tissues of stranded green sea turtles (Chelonia mydas) from the southern Atlantic coast of Brazil.

Silver (Ag), cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) concentrations were analyzed in tissues of juvenile green sea turtles (Chelonia mydas) found stranded along the southern Atlantic coast in Brazil. Green sea turtles were collected (n=29), measured (curved carapace length: CCL) and had their muscle, liver, and kidney dissected for metal concentration measurements. Sex was identified in 18 individuals (10 females and 8 males) through gonad histology.

Acute waterborne copper toxicity to the euryhaline copepod Acartia tonsa at different salinities: influence of natural freshwater and marine dissolved organic matter.

The influence of natural dissolved organic matter (DOM) on acute waterborne Cu toxicity was evaluated in the euryhaline copepod Acartia tonsa at 3 different water salinities. Three sources of freshwater DOM (extracted by reverse osmosis) and 2 sources of marine DOM (extracted using a solid-phase technique) were used. Artificial salt water was used to prepare the experimental media.

Waterborne copper exposure inhibits ammonia excretion and branchial carbonic anhydrase activity in euryhaline guppies acclimated to both fresh water and sea water.

Inhibition of ammonia excretion (J(amm)) is a common response to Cu exposure in freshwater (FW) and seawater (SW) organisms. To determine the mechanism of this response, a euryhaline species of guppy (Poecilia vivipara) was exposed to 20 μg Cu/l in FW (0 ppt) and SW (25 ppt) for 96 h. In both salinities, Cu transiently inhibited ammonia excretion (J(amm)) followed by a full recovery by the end of the 96 h exposure.

Effect of copper on ion content in isolated mantle cells of the marine clam Mesodesma mactroides.

The effect of copper on ion content (Na(+), K(+), Ca(2+), and Cl(-)) was evaluated in isolated mantle gills of the marine clam Mesodesma mactroides. Clams were collected at the Mar Grosso Beach (São José do Norte, Rio Grande do Sul [RS], southern Brazil), cryoanesthetized, and had their mantles dissected. Mantle cells were isolated and incubated in a calcium-free phosphate solution without (control) or with Cu (CuCl(2)).

Mechanisms of copper accumulation in isolated mantle cells of the marine clam Mesodesma mactroides.

In vivo copper accumulation was determined in tissues (mantle, gills, digestive gland, and hemolymph) following exposure to Cu (5 µM) for up to 96 h. Mantle was the tissue that accumulated the most Cu, followed by gill, digestive gland, and hemolymph. Therefore, in vitro Cu accumulation was evaluated in isolated mantle cells exposed to 0.

Acute toxicity, accumulation and tissue distribution of copper in the blue crab Callinectes sapidus acclimated to different salinities: in vivo and in vitro studies.

In vivo and in vitro studies were performed to evaluate acute toxicity, organ-specific distribution, and tissue accumulation of copper in Callinectes sapidus acclimated to two different experimental salinities (2 and 30 ppt). Blue crabs were quite tolerant to copper. Acute dissolved copper toxicity (96-h LC(50) and its corresponding 95% confident interval) was higher at salinity 2 ppt (5.