Occurrence of cocaine and benzoylecgonine in drinking and source water in the São Paulo State region, Brazil.

The occurrence of illicit drugs in natural waters (surface, source and drinking water) is of interest due to the poor sanitation coverage and the high consumption of drugs of abuse in Brazil. In addition, little is known about the effects of these compounds on aquatic organisms and human health. This work investigates the occurrence of cocaine (COC) and its major metabolite, benzoylecgonine (BE), in surface and drinking water collected in rivers from a populated geographic area in Brazil.

A preliminary nationwide survey of the presence of emerging contaminants in drinking and source waters in Brazil.

This is the first nationwide survey of emerging contaminants in Brazilian waters. One hundred drinking water samples were investigated in 22 Brazilian state capitals. In addition, seven source water samples from two of the most populous regions of the country were evaluated.

Organic micropollutants (OMPs) in natural waters: Oxidation by UV/H2O2 treatment and toxicity assessment.

Organic micropollutants (OMPs) are ubiquitous in natural waters even in places where the human activity is limited. The presence of OMPs in natural water sources for human consumption encourages the evaluation of different water purification technologies to ensure water quality. In this study, the Biobío river (Chile) was selected since the watershed includes urban settlements and economic activities (i.

Assessment of the Impact of Potential Tetracycline Exposure on the Phenotype of Aedes aegypti OX513A: Implications for Field Use.

Background: Aedes aegypti is the primary vector of dengue fever, a viral disease which has an estimated incidence of 390 million infections annually. Conventional vector control methods have been unable to curb the transmission of the disease. We have previously reported a novel method of vector control using a tetracycline repressible self-limiting strain of Ae.

Occurrence and potential risk of triclosan in freshwaters of São Paulo, Brazil--the need for regulatory actions.

Triclosan (TCS) is a broad-spectrum bactericide, highly toxic to algae, which is released into the environment via wastewater effluents. Predicted no-effect concentrations (PNECs) for aquatic biota have been proposed in the literature, varying from 1.4 to 1,550 ng/L, reflecting contradicting protection goals.

Ecotoxicity of TiO2 to Daphnia similis under irradiation.

Currently, there are a large number of products (sunscreen, pigments, cosmetics, plastics, toothpastes and photocatalysts) that use TiO(2) nanoparticles. Due to this large production, these nanoparticles can be released into the aquatic, terrestrial and aerial environments at relative high concentration. TiO(2) in natural water has the capacity to harm aquatic organisms such as the Daphnia (Cladocera) species, mainly because the photocatalytic properties of this semiconductor.

Bioluminescent yeast estrogen assay (BLYES) as a sensitive tool to monitor surface and drinking water for estrogenicity.

Estrogenic Endocrine Disrupting Chemicals (EDCs) are a concern due to their ubiquity and recognized adverse effects to humans and wildlife. Methods to assess exposure to and associated risks of their presence in aquatic environment are still under development. The aim of this work is to assess estrogenicity of raw and treated waters with different degrees of pollution.

Determination of antibiotics in Brazilian surface waters using liquid chromatography-electrospray tandem mass spectrometry.

A liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) method for the determination of antibiotics in water was developed and applied to Brazilian surface waters. Amoxicillin, ampicillin, cefalexin (CEF), ciprofloxacin (CIP), norfloxacin (NOR), sulfamethoxazole, tetracycline (TET), and trimethoprim were selected as target compounds due to their high consumption pattern in Brazil. LC and MS conditions were optimized to produce the maximum analytic response for each compound.

Elemental gaseous mercury flux at the water/air interface over the Negro River basin, Amazon, Brazil.

The amount of dissolved gaseous mercury (DGM) released annually into the atmosphere by water bodies in each of the 18 major sub-basins of the Negro River tributaries has been estimated for the wet season and adopted for the entire year. Using Remote Sensors (RS) and the Geographic Information System (GIS), an estimate was made for the total flooded area during the period of the wet season (May-July), which corresponds to around 10% of the total basin area. The estimates of DGM evasive flux values were made during four scientific campaigns and ranged from 0.

Sorption of mercury (II) in Amazon soils from column studies.

The sorption of Hg (II) onto four different types of Amazon soils from the A-horizon was investigated by means of column experiments under saturation conditions and controlled metal load. Higher organic matter contents in the soil resulted in higher Hg (II) adsorptions, reaching values as high as 3.8 mg Hg g(-1) soil.

Piranhas (Serrasalmus spp.) as markers of mercury bioaccumulation in Amazonian ecosystems.

Mercury (Hg) concentration in fish depends on feeding strategies and age/size within the species as well as on water parameters related to acidity and Hg speciation. We chose two species of piranhas (Serrasalmus aff. eigenmanni and Serrasalmus rhombeus) to test their suitability as markers of Hg bioaccumulation.

Stimulation of potato tuber respiration by cold stress is associated with an increased capacity of both plant uncoupling mitochondrial protein (PUMP) and alternative oxidase.

The CO2 evolution of intact potato tubers (Solanum tuberosum, L., var. "Bintje") was analyzed during a 10-day period of their warm (25 +/- 2 degrees C) or cold (5 +/- 1 degrees C) storage, to evaluate cold-stress effects on expression and activities of plant uncoupling mitochondrial protein (PUMP) and alternative oxidase (AOX).

Operational problems related to the preparation of the seawater soluble fraction of crude oil.

Owing to the importance of dissolution and weathering processes following oil spills, this work focused on the operational (quantitative) aspects related to the dissolution of petroleum-derived products, as well as the influence of solar light on both dissolution and the photoproduction of hydrogen peroxide. Four Brazilian crude oil samples were used to study the transfer process of organic compounds from the crude oil film to the aqueous phase (natural seawater) over a period of up to 45 days. Dissolved organic carbon (DOC), measured by non-dispersive infrared spectroscopy followed by high temperature catalytic combustion, was used to follow the partitioning between the two phases.