Isolated and mixed effects of pure and formulated abamectin and difenoconazole on biochemical biomarkers of the gills of Danio rerio.

Pesticides are released into the environment daily, and their effects on nontarget species in aquatic ecosystems have been widely reported. To evaluate the adverse effects caused in adults of Danio rerio species exposed to the pesticides abamectin, difenoconazole, and their commercial formulations (Kraft 36EC® and Score 250EC®), both isolated and in mixtures, biochemical biomarkers were analyzed in the gills of organisms exposed to sublethal concentrations. To this end, the activities of the enzymes 7-ethoxyresorufin-O-deethylase (EROD), glucuronosyltransferase (UDPGT), glutathione-S-transferase (GST), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), lipid hydroperoxide (LH), and malondialdehyde (MDA), which are indicative of oxidative stress, were measured after 48 h of exposure to the different pesticide treatments.

Lethal and sublethal toxicity of abamectin and difenoconazole (individually and in mixture) to early life stages of zebrafish.

In recent years, the need for the development of alternative test methods for the conventional acute fish toxicity test (AFT) with adult fish has often been discussed. In addition, concerns have been raised on the potential risks related with environmentally realistic pesticide mixtures since risk evaluations have traditionally been based on individual pesticides. The insecticide/acaricide abamectin and the fungicide difenoconazole are the main pesticides that are intensively used in Brazilian strawberry crop and are hence likely to occur simultaneously in edge-of-field waterbodies.

Red disperse dyes (DR 60, DR 73 and DR 78) at environmentally realistic concentrations impact biochemical profile of early life stages of zebrafish (Danio rerio).

Dyes have been used for more than twenty thousand years in textile, pharmaceutical, food, cosmetic, and photographic industries, among others. Despite their importance in these applications, dyes can be toxic and resistant to many degradation processes used in wastewater treatment plants. Although a large number of dyes have been released in the environments in high amounts, studies into the environmental toxicity of these substances are still scarce.

Single and mixture toxicity of abamectin and difenoconazole to adult zebrafish (Danio rerio).

Concerns have been raised in recent years on the potential risks related with pesticide mixtures that are likely to be present in agricultural edge-of-field waterbodies. Despite the high use of pesticides in tropical countries like Brazil, studies evaluating pesticide mixtures are especially scarce in the tropics. The insecticide abamectin and the fungicide difenoconazole are the main pesticides intensively used in Brazilian strawberry crop and are hence likely to occur simultaneously.

Toxicity of abamectin and difenoconazole mixtures to a Neotropical cladoceran after simulated run-off and spray drift exposure.

Aquatic risk assessments of pesticides in tropical countries have often been disputed for being largely based on risk evaluations conducted in temperate regions. Although pesticide sensitivity comparisons between temperate and tropical freshwater organisms have indeed not revealed consistent differences, risk assessments are currently still based on a relatively small tropical toxicity dataset. In addition, greater levels of runoff and spray drift may be expected in tropical than in temperate agroecosystems, indicating that aquatic life in edge-of-field water bodies is likely to be subjected to higher concentrations of pesticides and their mixtures.

Acute and chronic sensitivity, avoidance behavior and sensitive life stages of bullfrog tadpoles exposed to the biopesticide abamectin.

As compared to other aquatic organism groups, relatively few studies have been conducted so far evaluating the toxicity of pesticides to amphibians. This may at least partly be due to the fact that regulations for registering pesticides usually do not require testing amphibians. The sensitivity of amphibians is generally considered to be covered by that based on toxicity tests with other aquatic organisms (e.

Biochemical responses in mussels Perna perna exposed to diesel B5.

In Brazil B5 blend (5% biodiesel and 95% diesel oil) has been adopted as mandatory fuel since 2010 for automotive vehicles. Since little is known about the effects of B5 exposure can promote on antioxidant system of marine biota this study aimed to assess if B5 can generate modifications in antioxidant parameters of mussels Perna perna. To address this question mussels were exposed to two concentrations of B5 (0.

Biochemical biomarkers in Nile tilapia (Oreochromis niloticus) after short-term exposure to diesel oil, pure biodiesel and biodiesel blends.

Fossil fuels such as diesel are being gradually replaced by biodiesel, a renewable energy source, cheaper and less polluting. However, little is known about the toxic effects of this new energy source on aquatic organisms. Thus, we evaluated biochemical biomarkers related to oxidative stress in Nile tilapia (Oreochromis niloticus) after two and seven exposure days to diesel and pure biodiesel (B100) and blends B5 and B20 at concentrations of 0.