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A simple, repeatable and inexpensive laboratory practice applied to teach and discuss aquatic metal pollution and oxidative stress detoxification mechanisms through biomarker analyses, as well as important ecotoxicology concepts, is presented herein. It has been implemented in a university in Brazil to both undergraduate and Master's and PhD students, indicating usefulness to all these levels. Students learned to detect metallothionein and reduced glutathione concentrations in biological samples and investigate several variables of interest in biomonitoring assessments. In addition, statistical correlations were used to indicate the potential dual role played by MT in aquatic organisms, allowing for biological inferences regarding both aquatic metal pollution and oxidative stress detoxification mechanisms and maturing of ecotoxicological and biomonitoring concepts discussed and presented both theoretically and integrated to the laboratory findings.

The reports of fish cell cultivation date back to the early 20th century, and since then, it has become a tool of great importance for different areas of ichthyology, such as immunology, toxicology, and biotechnology. The cell cultivation methodology can vary according to the species and cell type, requiring knowledge of the specificities and characteristics of the target cell for them to be efficiently cultured. In this review, we address the main characteristics of the in vitro culture of fish cells, presenting their purposes, uses, main parameters, and different characteristics necessary for the culture environment. Finally, we present the experiences in Brazil using cell culture techniques. [ABSTRACT FROM AUTHOR]

Contaminants compounds like Heavy Metals and Polycyclic Aromatic Hydrocarbons (PAH's) are primarily sourced from industrial and urban areas. As pollutants, these chemical elements and compounds are potentially toxic and present the capacity to negatively impact the ecosystem, especially the most sensitive ones such as estuaries. Bivalves' species have been successfully utilized as monitoring tools to evaluate pollutants bioaccessibility around the globe. The present study assessed heavy metals (Zn, Cd, Ni, Fe, Cr, Cu and Pb), As and PAH's levels in two mollusk species (Perna perna and Crassostrea rhizophorae) from Santos Estuarine System, in São Paulo State, in order to compare the effectiveness of each species in the biomonitoring process. According to the obtained data, Perna perna mussels may be better indicators of environmental pollution than Crassostrea rhizophorae oysters for some metals (Iron and Nickel) and hydrocarbons. On the other hand, in the present study, oysters had a higher capacity for retaining zinc, copper, and cadmium, due to their peculiar physiological characteristics. [ABSTRACT FROM AUTHOR]

Self-medication is the use of drugs to treat self-diagnosed illnesses or symptoms, on one's own initiative, without the guidance of a healthcare professional. Poison centers play an important role in understanding the relationship between self-medication and poisoning. The objective of this study is to evaluate the clinical and epidemiological profile of patients exposed to and/or poisoned by different drugs through self-medication. This retrospective, cross-sectional, and descriptive study analyzed data from 2014 to 2020, provided by the Toxicological Information and Assistance Center of Santa Catarina, Brazil. Data were selected, tabulated, and analyzed by using descriptive statistics and group comparison with the chi-square test or Fisher's exact test. A P value <0.05 was considered statistically significant. There were 683 cases of self-medication identified. Most patients were female (62.8 percent) and between 20 and 29 years old (26.1 percent). A toxic dose of a substance was administered in only 22.8 percent of the cases, and five deaths were recorded. The most commonly used medications were anxiolytics (18 percent), followed by analgesics and antipyretics (15.4 percent). Paracetamol was the drug used in three of the five cases that resulted in deaths. This study demonstrates the prevalence of self-medication among women aged between 20 and 29 years old. Statistical analysis failed to show a relationship between a toxic dose and clinical manifestations. Anxiolytics, analgesics, and antipyretics are the most reported medications probably because healthcare professionals are mostly the ones who contact the center. Analgesics and antipyretics account for more than fifty percent of the deaths caused by self-medication in the present report. Some limitations such as secondary sources are related. We highlight the importance of health professionals in promoting the rational use of medicines, as well as poison centers in assisting the population and raising their awareness regarding the issue. [ABSTRACT FROM AUTHOR]

Petiveria alliacea L. (Phytolaccaceae) holds significant importance in the Amazon region, where it has been traditionally utilized in folk medicine. In this study, we conducted a comprehensive bibliometric analysis using conventional metrics, combined with a critical content review of its pharmacological and toxicological properties, to identify gaps in the existing literature that require further investigation. Our investigation identified a total of 55 articles that met the inclusion criteria for this study. Remarkably, Brazil emerged as the primary contributor within the scope of this review, indicating a strong presence of research from this country. Furthermore, professional scientific societies have played a pivotal role in facilitating the dissemination of scientific findings through specialist journals, fostering the sharing of research work within the community. Analysis of keyword co-occurrence revealed that "Petiveria alliacea", "plant extract", and "guatemala" were the most frequently encountered terms, indicating their significance within the literature. In terms of study designs, in vivo and in vitro were the predominant types observed, highlighting their prevalence in this field of study. Our study also identified a lack in knowledge yet to be investigated. [ABSTRACT FROM AUTHOR]

River dolphins of the genus Inia are among the most endangered cetacean species in the world. However, information on the elemental constitution of the blood and milk of these species is still quite scarce. This study aims to evaluate the wavelength‐dispersive X‐ray fluorescence (WD‐XRF) spectrometry to detect and quantify heavy metals in blood and milk samples of a free‐ranging female Amazon river dolphin (Inia geoffrensis) from Central Amazon, Brazil. The WD‐XRF method detected and quantified 14 elements (Na, Mg, Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Zn, and Cu) in the samples analyzed, in which 13 elements were in the blood and 14 were in the milk. The WD‐XRF method did not detect some heavy metals, including those already described for the Amazon river dolphin milk (e.g., mercury) detected by other analytical methods, such as atomic absorption spectrometry (AAS). However, it is possible that the samples analyzed may come from a non‐contaminated individual. Therefore, the joint use of different analytical methods is recommended for future analyses. In addition, both blood and milk samples presented high concentrations of some metals, and the health risks of botos are discussed. This result demonstrates that the WD‐XRF method is a viable analytical procedure for detecting certain elements and quantifying their concentrations in liquid biological samples of Amazonian cetaceans. [ABSTRACT FROM AUTHOR]

Jules Lefort (1816-1889) was a French pharmacist and chemist who did extensive research on toxicology and forensic tests, particularly for morphine and phosphorus. He studied the coloration produced by different reagents with morphine, narcotine, brucine, and strychnine, and the chemical and toxicological effects produced by morphine during its passage through the animal economy. Morphine resisted without alteration the most active and extended putrefaction of animal matter. Salts of iron sesquioxide were the best reagent for assuring the presence of morphine in powder or concentrated solution; iodic acid with ammonia could detect morphine in a liquid containing 1/10,000 part of the alkaloid, and morphine ingested in a continuous manner and in variable doses, would appear in the urine but not in the sweat. He proved that HCl gaseous was the best reagent for detecting the presence of digitaline in colorless liquids and that this compound could be neatly separated by dialysis. Leroy reported the differences between the ipecacuanhas originating from Brasil and from New Granada; the latter contained 23% less emetine. He also developed a very efficient procedure for the separation of this principle. Leroy found that the odor released by putrefying bodies, as well as their slight emission of light, were caused by a sulfur derivative and a combination of hydrogen and phosphorus. He also determined the amount of atropine present in the leaves and roots of belladonna and proposed an efficient method for its extraction. [ABSTRACT FROM AUTHOR]

Cururu toad (Rhinella marina group) is widely distributed in Brazil. Lesser grison (Galitic cuja) is a South American mustelid. This is the first report of natural poisoning in a free-ranging lesser grison by Rhinella toad parotoid gland secretion (PGS). Five minutes after biting a toad, the lesser grison developed convulsion, dying within 1.5 h. Mass spectrometry analysis of a milky-whitish secretion found in the lesser grison oral cavity allowed identification of a bufotoxin and a new bufonid peptide. • A free-ranging lesser grison had a lethal poisoning after an attempted predation on Rhinella sp. • The lesser grison (Galitic cuja) exposed to the cururu toad poison developed lethal neurologic signs. • A bufotoxin was detected in the toad secretion collected from the oral cavity of the affected lesser grison. • A novel bufonid peptide was discovered in the toad secretion collected from the oral cavity of the affected lesser grison. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the 96-h LC50 (lethal concentration for 50% of the test population in 96 h of observation) of mercury chloride (HgCl2) and evaluated its absorption in the gills, liver, and muscle of juvenile "curimatã-pacu," Prochilodus argenteus. The fish were exposed for 4 days to different concentrations of HgCl2: 0.000, 0.0375, 00.075, 0.150, 0.225, 0.300, and 0.400 mg L−1 to get the 96-h LC50, and the concentration of Hg in the tissues. The fish were exposed to different levels of HgCl2 (0.000, 0.0375, 00.075, 0.150, 0.225, and 0.300 mg L−1), for 4 and 7 days, when different tissues (gills, liver, and muscle) were sampled. The mercury concentration values obtained were compared between tissues, days, and concentration of mercury in the water. The 96-h LC50 for P. argenteus was 0.339 mg L−1 of HgCl2, within the range found for other neotropical and tropical species, showing a medium sensitivity. The concentration of Hg in the tissues increased from the muscle to the gills and liver, and according to the increasing concentration of HgCl2 in the water. The fish liver is the most suitable tissue for environmental monitoring and for the evaluation of the consumed fished. Despite being the tissue that least accumulated mercury, the muscle must be evaluated because it is the part consumed by the population. [ABSTRACT FROM AUTHOR]

Echinodorus macrophyllus (Kunth.) Micheli (Alismataceae), known as chapéu-de-couro in Brazil, is popularly used to treat inflammatory diseases. We have previously demonstrated a significant reduction in the acute inflammation for the aqueous extract of E. macrophyllus (AEEm) and its ethanolic fraction (Fr20) and described that hydroxycinnamoyl derivatives present in SF1 (Fr20 subfraction) showed higher anti-inflammatory properties by mechanisms that include a reduction of TNF-α, IL-1β, CKCL1/KC, LTB4, and PGE2 levels in exudate. This work describes the acute toxicological effect of SF1 subfraction on SW mice treated orally for five days in the air pouch model by evaluating the hematological and biochemical determinations on the blood samples; the relative organ weight and its histopathological analysis; the liver genotoxicity assessment and the activity of liver enzymes from xenobiotic metabolism. Fr20 was earlier fractionated on the Sephadex LH-20 column, yielding mainly four subfractions, including SF1. The SF1 toxicity was evaluated in mice challenged with carrageenan on the air pouch inflammation model and orally treated for five days. The body weight was monitored daily, and the organs were weighed after the euthanasia. Hematological and biochemical determinations were carried out using specific commercial kits and following the protocols provided by the manufacturers. The organs were fixed, sectioned, processed for hematoxylin and eosin staining, and analyzed by light microscopy. Genotoxicity assessment was performed by the alkaline single-cell gel electrophoresis. Livers were processed for ethoxyresorufin-O-deethylase (EROD) and Glutathione S-transferase (GST) assays. SF1 exhibited low toxicity, as no significant discrepancy was observed in the relative weight of the body organs of mice. Moreover, the daily treatment with SF1 did not alter the number and percentage of red blood cells or hemoglobin concentration in the blood. The treatment with SF1 did not affect the creatinine concentration, but the 25 mg/kg dose reduced the plasma urea level and uric acid, suggesting its use in treating acute renal failure. The parameters analyzed did not present biochemical alterations indicative of liver disease. Regarding serum triglyceride and cholesterol levels, a significant decrease was detected in both parameters in mice treated with SF1. In addition, the histopathological analysis showed that inflammatory focus in the livers seemed more relevant in the control groups than in those treated. There were no significant changes in the renal or splenic tissues of animals treated with SF1. Treatment with SF1 also does not have a genotoxic effect on liver cells. Treatment with SF1 showed no toxicity in mice at doses equivalent to those recommended for humans, which provides evidence of the safety of the therapeutic use of this subfraction. [Display omitted] • Fr20 was fractionated, and the SF1 subfraction exhibited higher anti-inflammatory properties. • SF1 phytochemical analysis indicates the major presence of hydroxycinnamoyl derivatives. • Previously, SF1 showed reduced inflammatory response induced by carrageen on the air pouch model. • In this study, no significant toxicity was observed in mice after five days of SF1 treatment with all tested doses. • All results provide evidence of the safety of the therapeutic use of this subfraction. [ABSTRACT FROM AUTHOR]

Microcystins (MCs) are potent toxins produced by environmental cyanobacterial blooms. The present study evaluated the effects of a Microcystis aeruginosa cyanobacterial lysate containing 0.1, 1, and 10 μg L−1 MC‐LR equivalent in the C. elegans Bristol N2 wild‐type and the effects caused by equivalent concentrations of a MC‐LR standard. The lysate was prepared from a culture of toxic strain (RST9501) originated from the Patos Lagoon Estuary (RS, Brazil). The minimal concentration necessary to cause significant effects in C. elegans under exposure to M. aeruginosa lysate or to MC‐LR standard were, respectively, 10 and 0.1 μg L−1 MC‐LR equivalent for growth and 10 and 1 μg L−1 MC‐LR equivalent for fertility. Reproduction (ie, brood size) was only affected by the exposure to 10 μg L−1 MC‐LR standard and was not affected by the lysate. The nematodes that were exposed to lysate containing 1 μg L−1 MC‐LR equivalent or MC‐LR were also analyzed for pharyngeal pumping and gene expression using RT‐qPCR. The worms' rhythmic contractions of the pharynx were similarly affected by the lysate containing 1 μg L−1 of MC‐LR equivalent and the MC‐LR standard. The MC‐LR standard caused down‐regulation of genes related to growth (daf‐16), fertility (spe‐10), and biotransformation (gst‐2). This is the first study to evaluate the effects of a toxic cyanobacterial lysate using the C. elegans model. This study suggests the organism as a potential biotest to evaluate toxicity of natural waters containing M. aeruginosa cells and to environmental risk assessment associated to cyanobacterial bloom events. [ABSTRACT FROM AUTHOR]

Water quality has declined globally due to increased contamination of aquatic ecosystems. The use of fish genotoxicity biomarkers may improve and complement parameters for environmental risk assessment. The aim of this study was to assess the genotoxicity of samples collected from streams of the Jordão River, a tributary of the Paranaíba River, Brazil with different levels of metal contamination, utilizing a native fish species to determine the sensitivity and viability of implementing a useful, reliable technique for routine biomonitoring programs. Chemical analysis of water and sediments collected from different sites indicated that a gradient of contamination existed as evidenced by different concentrations of metals detected. After chronic exposure to contaminated samples, micronucleus (MN) frequencies in fish erythrocytes were measured and correlation with environmental parameters determined. Sites where the water concentrations of the metals aluminum (Al), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) were high indicating a greater genotoxic potential of these elements. At the samples collected from the urban zone, a gradual increase was found for chromium (Cr), cadmium (Cd) and nickel (Ni) indicative of adverse impacts of discharge of urban effluents. Data demonstrated that Astyanax altiparanae, used in the test, exhibited a reliable sensitivity for detection of genotoxic consequences attributed to exposure to water samples collected near the discharge of industrial and domestic waste. [ABSTRACT FROM AUTHOR]

Annually, more than 1.2 million scorpion stings and more than 3,000 deaths occur worldwide. Tityus serrulatus Lutz and Mello, 1922 (Scorpiones, Buthidae) is the most medically relevant species in Brazil where it is spreading rapidly and causing over 90,000 cases of envenomation yearly. We monitored T. serrulatus longevity and ability to reproduce under conditions of food and/or water deprivation. We found that T. serrulatus is highly tolerant to food deprivation, with individuals enduring up to 400 days without food. On the other hand, access to water played a pivotal role in T. serrulatus survival. Food and water deprived scorpions showed weight reduction. Reproduction occurred throughout the year for food-deprived scorpions and controls, but not in the water-deprived groups. Remarkably, food-deprived animals were able to give birth after 209 days of starvation. Tityus serrulatus resistance to food and water deprivation is likely to be an additional factor underlying this species' geographic expansion and the difficulties encountered in controlling it. [ABSTRACT FROM AUTHOR]

The bacterium Actinobacillus pleuropneumoniae is the etiological agent of Contagious Porcine Pleuropneumonia, a disease responsible for economic losses in the swine industry worldwide. A. pleuropneumoniae is capable of producing proteinaceous exotoxins responsible for inducing hemorrhagic lesions, one of which is ApxI. Few studies have conducted an in-depth evaluation of polymorphisms of the nucleotides that make up the ApxI toxin gene. Here we analyze the polymorphisms of the apxIA gene region of A. pleuropneumoniae serovar 5 isolated from swine in different regions in Brazil and report the results of molecular sequencing and phylogenetic analysis. Analysis of the apxIA gene in 60 isolates revealed the presence of genetic diversity and variability. The polymorphisms in the nucleotide sequences determined the grouping of the Brazilian sequences and five more sequences from the GenBank database into 14 different haplotypes, which formed three main groups and revealed the presence of mutations in the nucleotide sequences. The estimation of selection pressures suggests the occurrence of genetic variations by positive selective pressure on A. pleuropneumoniae in large groups of animals in relatively small spaces. These conditions presumably favor the horizontal dissemination of apxIA gene mutations within bacterial populations with host reservoirs. As a result, the same serovar can demonstrate different antigenic capacities due to mutations in the apxIA gene. These alterations in sequences of the apxIA gene could occur in other areas of countries with intense swine production, which could lead to differences in the pathogenicity and immunogenicity of each serovar and have implications for the clinical status or diagnosis of A. pleuropneumoniae. [ABSTRACT FROM AUTHOR]

Snakebite envenomation is a neglected condition that constitutes a public health problem in tropical and subtropical countries, including Brazil. Interestingly, some animals are resistant to snake envenomation due to the presence of inhibitory glycoproteins in their serum that target toxic venom components. DM64 is an acidic glycoprotein isolated from Didelphis aurita (opossum) serum that has been characterized as an inhibitor of the myotoxicity induced by bothropic toxins bearing phospholipase A2 (PLA2) structures. This antitoxic protein can serve as an excellent starting template for the design of novel therapeutics against snakebite envenomation, particularly venom-induced local tissue damage. Therefore, the aim of this work was to produce a recombinant DM64 (rDM64) in the methylotrophic yeast Pichia pastoris and to compare its biological properties with those of native DM64. Yeast fermentation in the presence of Pefabloc, a serine protease inhibitor, stimulated cell growth (~1.5-fold), increased the rDM64 production yield approximately 10-fold and significantly reduced the susceptibility of rDM64 to proteolytic degradation. P. pastoris fermentation products were identified by mass spectrometry and Western blotting. The heterologous protein was efficiently purified from the culture medium by affinity chromatography (with immobilized PLA2 myotoxin) and/or an ion exchange column. Although both native and recombinant DM64 exhibit different glycosylation patterns, they show very similar electrophoretic mobilities after PNGase F treatment. rDM64 formed a noncovalent complex with myotoxin II (Lys49-PLA2) from Bothrops asper and displayed biological activity that was similar to that of native DM64, inhibiting the cytotoxicity of myotoxin II by 92% at a 1:1 molar ratio. [ABSTRACT FROM AUTHOR]

Introduction: Magnesium sulfate (MgSO4) is the drug of choice for the prevention and control of seizures in the management of severe preeclampsia/eclampsia. Several barriers have been identified in the use of MgSO4, especially in low and middle-income settings. Objective: To describe the obstetrician’s perception on possible reasons for underutilizing magnesium sulfate to treat preeclampsia/eclampsia. Method: A qualitative clinical study, based on phenomenological reference by semi-structured interviews and open-ended discussions with obstetricians of the public healthcare system in primary care units (PCU) and referral maternity hospitals (RMH), in a southeastern Brazilian city. Results: Fear of drug toxicity was the major cause for not prescribing the medication in PCU. Fear was justified by insufficient technical, structural and organizational resources of healthcare facilities and by a shortage of physicians properly trained for adequate drug use. Conclusion: Fear of toxicity of magnesium sulfate was the main barrier towards timely and proper drug use. Periodic skill development and training of obstetricians, along with integration of the medical team in the work environment may contribute to decrease fear, ensuring safety of drug prescription and thus possibly reducing adverse outcomes related to PE. [ABSTRACT FROM AUTHOR]

The mosquito Aedes aegypti is the primary vector of different arboviruses and represents a major public health problem. Several Brazilian populations of Ae. aegypti have developed resistance to temephos, the most used organophosphate larvicide. New tools which are less harmful to the environment and safer for humans are becoming increasingly important to control this insect vector. Spinosad, an aerobic fermentation product of a soil actinobacteria, has a favorable environmental profile. It presents selective insecticide properties, a mechanism of action that differs from those of many synthetic chemical insecticides. The toxicity of spinosad and temephos to Aedes aegypti populations from Brazil, which were previously exposed to temephos, were investigated in this study. Larval susceptibility (LC50) to temephos varied from 3μg/L for Rockefeller up to 260 μg/L for Santana do Ipanema field derived population. Larval susceptibility (LC50) to spinosad varied from 23μg/L for Rockefeller up to 93μg/L for Marilia field derived population. In addition, a semi-field trial was performed to evaluate spinosad (NatularTM DT) initial efficacy and persistence toward four field-derived lineages and the Rockefeller lineage, used as an internal control. Spinosad was tested at 0.5mg active ingredient/L in 200L capacity water tanks. Mortality was recorded each 24 hours after exposition and tanks were further recolonized once per week with mortality being recorded daily for eight weeks. Spinosad provided a level equal or superior to 80% mortality during a seven to eight week evaluation period. The assessed populations did not present cross-resistance between spinosad and temephos in laboratory conditions. It demonstrates that spinosad may be a promising larvicide for the control of Ae. aegypti, especially for populations in which resistance to temephos has been detected. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Alibertia edulis , popularly known as “marmelo do Cerrado” is a native plant from the brazilian Cerrado. It has high food and ornamental potential and the tea leaves are currently used as hypoglycemic, antihypertensive and diuretic. Aim of the study In order to evaluate the safety of the aqueous extract of Alibertia edulis leaves (AEAE), the acute and subacute toxicity tests were performed in male and female Wistar albino rats. Materials and methods The experiments were performed in accordance with the OECD guidelines 425 and 407. For the acute toxicity, one single dose of the AEAE (2000 mg/kg) was administered by gavage to five female rats. The animals were observed for 14 days for any signs of toxicity and death. In the subacute toxicity, four different doses (125, 250, 500 and 1000 mg/kg) of the AEAE were administered to male and female rats for 28 consecutive days. A satellite group received the maximum dose (1000 mg/kg) for 28 days and remained untreated for 14 more days in order to observe reversibility, persistence, or delayed occurrence of toxic effects. The five parameters of the Hippocratic screening, body weight, food and water intake were daily observed. At the end of the experiment, blood samples were collected for the hematological and biochemical analysis. The vital and reproductive organs were inspected for any histopathological changes. Results No deaths or behavioral changes were observed during both experiments as well as no changes on organ weights, biochemical, hematological and histopathological parameters that could indicate any signs of toxicity. Conclusion All doses tested can be considered safe in rats and the LD 50 is higher than 2000 mg/kg. Therefore, further assessments are required in order to proceed to clinical studies in humans. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated the harmful effects of atmospheric pollutants on cardiac systems because of the presence of particulate matter (PM), a complex mixture of numerous substances including trace metals. In this study, the toxicity of PM 2.5 from two regions, rural (PM 2.5 level of 8.5 ± 4.0 μg m −3 ) and industrial (PM 2.5 level of 14.4 ± 4.1 μg m −3 ) in Brazil, was investigated through in vivo experiments in rats. Metal accumulation and biochemical responses were evaluated after rats were exposed to three different concentrations of PM 2.5 in saline extract (10× dilution, 5× dilution, and concentrated). The experimental data showed the bioaccumulation of diverse trace metals in the hearts of groups exposed to PM 2.5 from both regions. Furthermore, mobilization of the antioxidant defenses and an increase in lipid peroxidation of the cardiac tissue was observed in response to the industrial and rural area PM 2.5 . Glutathione-S-transferase activity was increased in groups exposed to the 5× and concentrated rural PM 2.5 . Additionally, ATP-binding cassette (ABC) transporter activity in the cardiac tissue exposed to PM 2.5 was reduced in response to the 5× dilution of the rural and industrial region PM 2.5 . Histological analysis showed a decrease in the percentage of cardiac cells in the heart at all tested concentrations. The results indicate that exposure to different concentrations of PM 2.5 from both sources causes biochemical and histological changes in the heart with consequent damage to biological structures; these factors can favor the development of cardiac diseases. [ABSTRACT FROM AUTHOR]

Brazil is the third largest contributor to Green Analytical Chemistry, and there is significant participation of toxicologists in the development and improvement of environmental techniques. Currently, toxicologists have their own strategies and guidelines to promote the reduction/replacement or elimination of solvents, reduce the impacts of derivatization and save time, among other objectives, due to the peculiarities of toxicological analysis. Thus, this review aims to propose the concept of Green Analytical Toxicology and conduct a discussion about its relevance and applications specifically in forensic toxicology, using the microextraction methods developed for the determination of cocaine and its metabolites as examples., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Herbicides are the most commonly applied pesticides in Brazil, specifically those based on glyphosate, and are used for different crops, near the habitats of annual killifish. Annual killifish presents a short life cycle with generally restricted geographic distribution. In this context, we evaluated the effect of the Roundup Original© (65, 130 and 260 µg. L−1 of glyphosate) herbicide on different development stages (adult-young and senile) of the annual killifish (Cynopoecilus sp.). We quantified the oxidative balance markers (superoxide dismutase, catalase, glutathione S-transferase, lipid peroxidation levels, and total proteins). We observed that the senile individuals presented 2-fold higher lipid peroxidation levels associated with the maintenance of superoxide dismutase and catalase activity levels even after exposure to the herbicide. However, senile subjects were negatively impacted by the exposure to formulations containing glyphosate, and this was related to a loss of glutathione S-transferase activity. Our research demonstrated that the established physiological markers and this species look promising for toxicology studies. [Display omitted] • Oxidative stress markers were determined in young-adult and senile males of Killifish. • Annual killifish showed no mortality when exposed to concentrations of glyphosate. • Antioxidant system of young adults of Cynopoecilus sp. proved to be highly efficient. • Senile killifish showed an increase in LPO without changing SOD and CAT. • Exposed senile show a decrease in glutathione S-transferase activity. [ABSTRACT FROM AUTHOR]

Background: Snakebites is a neglected disease and in Brazil is considered a serious health problem, with the majority of the snakebites caused by the genus Bothrops. Antivenom therapy and other first-aid treatments do not reverse local myonecrose which is the main sequel caused by the envenomation. Several studies have shown the effectiveness of low level laser (LLL) therapy in reducing local myonecrosis induced by Bothropic venoms, however the mechanism involved in this effect is unknown. In this in vitro study, we aimed to analyze the effect of LLL irradiation against cytotoxicity induced by Bothrops jararacussu venom on myoblast C2C12 cells. Methodology: C2C12 were utilized as a model target and were incubated with B. jararacussu venom (12.5 μg/mL) and immediately irradiated with LLL at wavelength of red 685 nm or infrared 830 nm with energy density of 2.0, 4.6 and 7.0 J/cm2. Effects of LLL on cellular responses of venom-induced cytotoxicity were examined, including cell viability, measurement of cell damage and intra and extracellular ATP levels, expression of myogenic regulatory factors, as well as cellular differentiation. Results: In non-irradiated cells, the venom caused a decrease in cell viability and a massive release of LDH and CK levels indicating myonecrosis. Infrared and red laser at all energy densities were able to considerably decrease venom-induced cytotoxicity. Laser irradiation induced myoblasts to differentiate into myotubes and this effect was accompanied by up regulation of MyoD and specially myogenin. Moreover, LLL was able to reduce the extracellular while increased the intracellular ATP content after venom exposure. In addition, no difference in the intensity of cytotoxicity was shown by non-irradiated and irradiated venom. Conclusion: LLL irradiation caused a protective effect on C2C12 cells against the cytotoxicity caused by B. jararacussu venom and promotes differentiation of these cells by up regulation of myogenic factors. A modulatory effect of ATP synthesis may be suggested as a possible mechanism mediating cytoprotection observed under laser irradiation. [ABSTRACT FROM AUTHOR]

The introduction of an agricultural pest species into a new environment is a potential threat to agroecosystems of the invaded area. The phytosanitary concern is even greater if the introduced pest’s phenotype expresses traits that will impair the management of that species. The invasive tomato borer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is one such species and the characterization of the insecticide resistance prevailing in the area of origin is important to guide management efforts in new areas of introduction. The spinosad is one the main insecticides currently used in Brazil for control of the tomato borer; Brazil is the likely source of the introduction of the tomato borer into Europe. For this reason, spinosad resistance in Brazilian populations of this species was characterized. Spinosad resistance has been reported in Brazilian field populations of this pest species, and one resistant population that was used in this study was subjected to an additional seven generations of selection for spinosad resistance reaching levels over 180,000-fold. Inheritance studies indicated that spinosad resistance is monogenic, incompletely recessive and autosomal with high heritability (h2 = 0.71). Spinosad resistance was unstable without selection pressure with a negative rate of change in the resistance level ( = −0.51) indicating an associated adaptive cost. Esterases and cytochrome P450-dependent monooxygenases titration decreased with spinosad selection, indicating that these detoxification enzymes are not the underlying resistance mechanism. Furthermore, the cross-resistance spectrum was restricted to the insecticide spinetoram, another spinosyn, suggesting that altered target site may be the mechanism involved. Therefore, the suspension of spinosyn use against the tomato borer would be a useful component in spinosad resistance management for this species. Spinosad use against this species in introduced areas should be carefully monitored to prevent rapid selection of high levels of resistance and the potential for its spread to new areas. [ABSTRACT FROM AUTHOR]

Background Despite being the second largest tobacco producer in the world, Brazil does not have prevalence studies about green tobacco sickness (GTS). Methods A cross-sectional study was carried out on a sample of Brazilian tobacco workers. The sample was described according to socio-demographic, behavioral, and occupational variables. Gender-stratified multivariate analyses examined variables associated with GTS. Results GTS prevalence among men in the previous month was 6.6%, while among women it was 11.9%. Among men, age, being a non-smoker, hanging tobacco sticks in the barn, harvesting wet leaves, and exposure to physical exertion were risk factors for GTS. Among women, tying hands of tobacco, transporting bales, harvesting wet leaves, having had contact with pesticides, and exposure to physical exertion were positively associated with GTS. Conclusion Research is required to improve methods for GTS screening, as well as the ability to distinguish GTS from pesticide poisoning. Health professionals should be trained to diagnose and treat GTS. Am. J. Ind. Med. 57:726-735, 2014. © 2014 The Authors. American Journal of Industrial Medicine Published by Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Basic research is fundamental for discovering potential diagnostic and therapeutic tools, including drugs, vaccines and new diagnostic techniques. On this basis, diagnosis and treatment methods for many diseases have been developed. Presently, discovering new candidate molecules and testing them in animals are relatively easy tasks that require modest resources and responsibility. However, crossing the animal-to-human barrier is still a great challenge that most researchers tend to avoid. Thus, bridging this current gap between clinical and basic research must be encouraged and elucidated in training programmes for health professionals. This project clearly shows the challenges faced by a group of Brazilian researchers who, after discovering a new fibrin sealant through 20 years of painstaking basic work, insisted on having the product applied clinically. The Brazilian government has recently become aware of this challenge and has accordingly defined the product as strategic to the public health of the country. Thus, in addition to financing research and development laboratories, resources were invested in clinical trials and in the development of a virtual platform termed the Virtual System to Support Clinical Research (SAVPC); this platform imparts speed, reliability and visibility to advances in product development, fostering interactions among sponsors, physicians, students and, ultimately, the research subjects themselves. This pioneering project may become a future model for other public institutions in Brazil, principally in overcoming neglected diseases, which unfortunately continue to afflict this tropical country. [Copyright &y& Elsevier]

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PCBs are synthetic organic compounds that were widely used in industry as dielectric fluids in transformers and capacitors, paints and lubricants hydraulic oils. After being detected in the environment on the end of 60, then they were identified as contaminants in the whole ecosystem, including the air, water, soil, plants, animals, humans and food, which led to its prohibition in 1977, in the United States, and in 1981, in Brasil. Nevertheless, its use is still allowed in our country in old electronics, until its replacement by other free PCB product. This has resulted in several use episodes, inadequate storage and disposal, contaminating the environment, animals, humans and all the food chain. Studies show that these compounds are able to cause significant changes, such as neurotoxicity, endocrine disruption, and immunosuppression, among others. According to the IARC, PCBs are classified in Group 2A (probably carcinogenic to humans), with the exception of PCB 126, which belongs to Group 1 (carcinogenic to humans). Because their high lipophilicity, accumulates in the food chain and, consequently, has been detected often in many kinds of food, which is the main source of human contamination. The aim of this review is to present the mains aspects related to polychlorinated biphenyls in foods, including their characteristics, toxicological aspects and occurrence. [ABSTRACT FROM AUTHOR]

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Abstract: Ethnopharmacological relevance: Solanum cernuum Vellozo is a Brazilian shrub or small tree, restricted to Southwest states of the country. It has been widely used for the treatment of many ailments. The pharmacological activity of the extract on gastric ulcer has been the major therapeutic target proposed by the population investigated. Materials and methods: In the acute toxicity test was used increasing doses of the extract (2, 4, 8, 12, 16, 20 and 25g of extract per kilogram of body weight). The animal behavior was observed from 5h after a single administration of the extract and subsequently monitored daily until the fourteenth day, beyond the calculation of the estimated LD50 of the extract. In the test sub-chronic toxicity was used two doses of the extract (0.1 and 1.4g/kg) and the parameters analyzed over 31 days were: body weight, food intake, behavior, respiratory rate, movement and mortality of animals. After anesthesia, blood samples were collected for hematological and biochemical analysis. The animals were euthanized followed by macroscopic analysis of the stomach and intestine. Liver, lungs and kidneys were removed, weighed and analyzed histopathologically. Results: In the acute toxicity test was observed a dose-dependent mortality and the value of estimated LD50 was 14.50g/kg. In the hematological and biochemical analyses there were significant increase in the activities of AST and ALT indicating liver toxicity, but the extract was not able to alter food intake, body weight and organ weights after 31 days of treatment and it did not produce significant histopathological changes. Conclusion: Therefore we can consider the hydroalcoholic extract of Solanum cernuum Vell as practically non-toxic in acute administration and safe in the sub-chronic administration, as hepatotoxicity was observed only with the highest dose used, not with the dose routinely used by the native population. [Copyright &y& Elsevier]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The use of sewage mud in agriculture has generated several discussions due to the risks of soil contamination mainly by metals. Due to the intimate contact of the diplopods with soil, they have been successfully used in ecotoxicological analyses. The impact of the external environment in the physiological changes in organs and tissues of different organisms can be reflected by the ultrastructural changes of their cells. Using the transmission electron microscopy, this study aimed to analyze the ultrastructural alterations in the midgut of the diplopod Rhinocricus padbergi exposed to substrate containing sewage mud from a Sewage Treatment Station of São Paulo State, Brazil. Therefore, it was sought to identify cellular alterations resulting from the subchronic exposure (90 days of exposure) of the animals to complex and potentially toxic mixtures such as sewage mud at different concentrations (1%, 10%, and 50%). The control group presented integrity in the cells and tissues that constitute the midgut. The animals exposed to sewage mud at 10% and 50% died before the 90 days of exposure. The analysis of the midgut of the animals exposed to 1% of sewage mud showed alterations in the epithelial cells, cells of the fat body layer, and hepatic cells. The main alterations observed were cytoplasmatic vacuolization, loss of the plasmatic membrane, and nuclear envelope integrity. We conclude that the mud sample presents a mixture of complex substances of cytotoxic and genotoxic action to the diplopod, causing cell death, since both the nucleus and other cellular compartments were damaged. [ABSTRACT FROM AUTHOR]

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Abstract: The acute poisoning of chronic renal patients during hemodialysis sessions in 1996 in Caruaru City (Pernambuco State, Brazil) stimulated an intensive search for the cause of this severe complication. This search culminated in the identification of microcystins (MC), hepatotoxic cyclic heptapeptides produced by cyanobacteria, as the causative agents. More than ten years later, additional research data provides us with a better understanding of the factors related to cyanobacterial bloom occurrence and production of MC in Brazil and other South American countries. The contamination of water bodies and formation of toxic blooms remains a very serious concern, especially in countries in which surface water is used as the main source for human consumption. The purpose of this review is to highlight the discoveries of the past 15 years that have brought South American researchers to their current level of understanding of toxic cyanobacteria species and that have contributed to their knowledge of factors related to MC production, mechanisms of action and consequences for human health and the environment. [ABSTRACT FROM AUTHOR]

Abstract: Toxinology in Brazil developed specially during the 19th and 20th centuries. A very brief description of the main contributions made by pioneer toxinologists is presented here in an attempt to give an idea of the evolution of toxinology in our country, from its first steps until the XVI World Congress of the International Society on Toxinology, held in Recife, Brazil in March of 2009. [ABSTRACT FROM AUTHOR]

The relevance of fetal abnormalities noted at maternally toxic doses is a long-standing issue regarding the interpretation of findings of segment II studies. A number of diseases and conditions during pregnancy are known to adversely affect embryo/fetal development, and along this line many scientists believe that any marked disturbance of maternal homeostasis produced by chemical exposure may eventually produce a teratogenic effect. Although there is little doubt that developmental toxicity may be maternally mediated, the notion that, in principle, any maternal toxicity leads to birth defects is disputed. When embryotoxicity is noted only within the maternally toxic dose range, it is not possible to ascertain whether it is in fact maternally mediated or not (i.e., embryo development may have been impaired by a direct action of the chemical at doses that also adversely affect the mother; in these circumstances it would still be a selective developmental toxicant). However, currently, a chemical is not regarded as a “developmental toxicant” (or “teratogenic agent”) if embryotoxicity is apparent only at doses that are also toxic to the mother. In the European Union, developmental hazard identification exerts a strong influence on the classification and labeling of chemicals. In Brazil, registration of any pesticide that proved to be teratogenic in animal studies is strictly forbidden by law (Pesticide Law, Federal Law 7.802, 1989). Therefore, interpretation of findings from developmental toxicity studies in light of maternal toxicity is particularly relevant to regulatory agencies, and becomes even more important when labeling or cutoff decision-making criteria are adopted regarding teratogenicity. [ABSTRACT FROM AUTHOR]

Disposal of tons of sludge produced daily by sewage treatment plants in large cities is a serious problem. Because recycling and application in agriculture have been proposed, the Brazilian National Environmental Council (CONAMA, 2006) issued a legal norm that regulates the use of the sewage sludge (SS) in crops. Due to the complex chemical nature of such products, characterization by analytical methods for health and environmental risk assessment has severe limitations. To overcome such limitations, it is necessary to (1) assess the toxicological potential of SS and (2) identify possible adverse effects in vivo in order to provide critical information for future environmental regulations. The present study was conducted to determine the potential toxicity of SS obtained from a representative urban treatment plant located in the Sao Paulo State, Brazil. Male and female Wistar rats were fed ad libitum a pelleted diet containing varying amounts of SS. No relevant clinical, hematological, urinary, or gross organ morphological alterations were observed in both genders of rats orally exposed to SS at up to 3.8 g/kg/d for 90 d. Sewage slude produced increased incidence of centrilobular hepatocyte hyperplasia at the high dose and significantly increased aspartate aminotransferease (AST) activities at all doses in both genders. Although the present data indicate some liver involvement, these alterations were considered adaptative and not toxicologically relevant, as the responses were relatively mild, not dose dependent, and no other parameters were markedly affected. The present results may contribute to the establishment of protocols for potential usage in SS agricultural soil application. [ABSTRACT FROM AUTHOR]

Acute cytotoxicity (neutral red assay), AhR-mediated toxicity (CYP P450 1A induction potential—EROD assay) and concentrations of PAHs were recorded in RTL-W1 cells to assess the ecotoxicological potential of sediments from reservoirs along the Tietê River and the Pinheiros River (Brazil). Almost all sediments tested induced cytotoxicity and stimulated cytochrome P450-associated EROD activity. Toxicity increases from Tietê River spring to São Paulo city region and decreases towards downstream. A closer analysis of chemical measurements of PAHs and results from bioassay revealed that the PAHs analyzed could not explain more than 7% of the EROD-inducing potencies. Results confirm that most of the toxicity is due to the discharges of the metropolitan area of São Paulo. Moreover, they indicate additional sources of pollutants along the river course, which contribute to the degradation of each reservoir. [Copyright &y& Elsevier]

Studies have shown that autologous hematopoietic SCT (HSCT) can be used as an intensive immunosuppressive therapy to treat refractory patients and to prevent the progression of multiple sclerosis (MS). This is a prospective multicentric Brazilian MS trial comparing two conditioning regimens: BEAM/horse ATG and CY/rabbit ATG. Most (80.4%) of the 41 subjects in the study had the secondary progressive MS subtype and the mean age was 42 years. The baseline EDSS score in 58.5% of the subjects was 6.5 and 78% had a score of 6.0 or higher, respectively. The complication rate during the intra-transplantation period was 56% for all patients: 71.4% of the patients in the BEAM/hATG group and 40% in the CY/rATG group (P=0.04). Three subjects (7.5%) died of cardiac toxicity, sepsis and alveolar hemorrhage, all of them in the BEAM/ATG group. EFS was 58.54% for all patients: 47% in the BEAM/hATG group and 70% in the CY/rATG group (P=0.288). In conclusion, the CY/rATG regimen seems to be associated with similar outcome results, but presented less toxicity when compared with the BEAM/hATG regimen. Long-term follow-up would be required to fully assess the differences in therapeutic effectiveness between the two regimens. [ABSTRACT FROM AUTHOR]

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Introduction. Pesticides are the second major cause of poisoning in Brazil, but information about the chemicals involved and the clinical management of patients is scarce. Methods. This study is a retrospective review of 709 pesticide cases reported to a toxicological information center from 2004 to 2007. Results. Over 90% of the cases occurred after accidental or self-poisoning; more than 60% of the accidents involved children up to 4 years old, mainly with domestic pyrethroid insecticides. One hundred ninety-four cases involved chumbinho, an illegal rodenticide known to contain acetylcholinesterase inhibitor insecticides, mainly aldicarb. In about half the cases, the individuals were admitted to hospitals. Those poisoned with acetylcholinesterase inhibitors stayed longer and most of them displayed pronounced clinical signs of poisoning (Poisoning Severity Score grades 2-4); 14 of the 18 deaths reported occurred with these products. Atropine was given to about 30% of the individuals, including to some with no cholinergic symptoms or exposed to non-acetylcholinesterase inhibitors. All 81 poisonings with coumarin were asymptomatic, but in half of the cases the individuals received vitamin K. Conclusions. The lack of laboratory support to confirm the chemical involved in the poisonings certainly contributed to the unnecessary antidote administration. In spite of continuing government efforts, poisoning with chumbinho is still a major problem in the country. [ABSTRACT FROM AUTHOR]

A liquid alcoholic extract of Papaver somniferum named Elixir Paregorico® is extensively used for diarrheal diseases in Brazil. Its increased popularity has brought concerns and fears over the safety of this herbal product. Given the lack of investigative clinical studies, in this regard, this study investigated whether Elixir Paregorico® administration causes any noticeable toxic effects in healthy volunteers. In all, 28 middle-aged healthy male (n = 14) and female (n = 14) were enrolled. After screening and a washout period, eligible subjects received four oral doses per day of Elixir Paregorico® (3 mL diluted in 30 mL of water) over a 10-day period. Altogether, all 28 participants completed the study. The results of hematological and biochemical tests performed pre and post-treatment were within the normal range. In both male and female volunteers, there were no statistical differences (P > 0.05) in the results of clinical and laboratory tests performed at screening, on 5th and 10th day visits, and at final assessment. Although mild adverse events were related, which subsided spontaneously, no serious untoward reactions were reported following Elixir Paregorico® administration. To our knowledge, this is the first demonstration that Elixir Paregorico® administered four times a day for 10 days is safe and does not cause any noticeable toxic effect in healthy volunteers. [ABSTRACT FROM AUTHOR]

The article discusses a study which evaluated the toxicological information on labels of cleaning products analyzed at the National Institute of Quality Control in Health in Rio de Janeiro, Brazil. It was found by researchers that the incidence of inadequate labels was higher than described by other authors because of the kind of products and the statements evaluated. Several important first aid information are also discussed.

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Glyphosate is the active ingredient and polyoxyethyleneamine is the surfactant present in the herbicide Roundup® formulation commercialized in Brazil. The aim of this study was to assess the reproductive effects of glyphosate-Roundup® on male and female offspring of Wistar rats exposed during pregnancy and lactation. Dams were treated orally with water or 50, 150 or 450 mg/kg glyphosate during pregnancy (21–23 days) and lactation (21 days). These doses do not correspond to human exposure levels. The results showed that glyphosate-Roundup® did not induce maternal toxicity but induced adverse reproductive effects on male offspring rats: a decrease in sperm number per epididymis tail and in daily sperm production during adulthood, an increase in the percentage of abnormal sperms and a dose-related decrease in the serum testosterone level at puberty, and signs of individual spermatid degeneration during both periods. There was only a vaginal canal-opening delay in the exposed female offspring. These findings suggest that in utero and lactational exposure to glyphosate-Roundup® may induce significant adverse effects on the reproductive system of male Wistar rats at puberty and during adulthood. [ABSTRACT FROM AUTHOR]

Abstract: Two sewage sludge samples collected from an urban as well as a rural area in Brazil and one sludge sample originating from the city of Balingen, Baden-Württemberg, South Germany, were investigated in respect to contamination with heavy metals, PCDD/F and PCB. The results were compared to PCDD/F and indicator-PCB mean values found in the region of Baden-Württemberg. The observed toxicity equivalents of PCDD/F found in the Brazilian samples, were below the upper limit specified by German legislation for final disposal or agricultural use in soils. Both the PCB and heavy metal values exceeded this limit. The PCDD/F congener/homologue profiles found in the Brazilian samples indicated that the urban sewage sludge shows a contamination where both chlorophenols and depositional sources appear to be contributing to the contamination pool. The enrichment of highly chlorinated PCDD/F groups in the sludge of semi-rural origin is probably due to transport phenomena effects. For the German sludge sample, depositional sources seem to be the main PCDD/F contamination pathway. Regarding PCB, both Brazilian samples show a homologue profile that indicates a contamination stemming from technical PCB formulations like Clophen A50 and Clophen A60 or equivalent. [Copyright &y& Elsevier]

No abstract available. [ABSTRACT FROM AUTHOR]

During the monitoring of toxic cyanobacteria in the Utinga Reservoir, which is the main drinking water supply for the city of Bele´m, PA, Brazil, a Radiocystis fernandoi strain (SPC714) was isolated. This non-axenic strain was submitted to a toxicity bioassay with mice and microcystin production analyzed by HPLC-DAD. The species was identified based on cultured and natural preserved material. Morphometric, developmental and reproductive characteristics were analyzed. The strain was cultured in liquid ASM-1 medium, at 25±1 °C, at an incident irradiance of 20 μmol photon m−2 s−1 and constant aeration. At the end of the exponential growth phase, cells were lyophilized and submitted to toxicity tests. The strain showed high toxicity to mice, by intraperitoneal route, with an approximate LD100 of 60 mg kg−1 of body weight, producing characteristic symptoms of hepatotoxicity. Analyses performed by HPLC-DAD confirmed the production of microcystins, in a concentration of 3.83 μg mg−1 of lyophilized cells. This is the first reference related to the toxicity of the genus Radiocystis. [Copyright &y& Elsevier]

The Pantanal is a 140,000 km2 floodplain wetland stretching across western Brazil and parts of Bolivia and Paraguay. Gold mining with mercury (Hg) amalgamation has thrived since 1980 along its northern rim. We quantified Hg accumulation in sediment cores (N = 5) and food chains in this general region of the northern Pantanal and in a reference region, 200 km deeper into the wetland (Acurizal). Cores were dated with 210Pb and 137Cs using direct gamma-assay. Total Hg was analyzed by cold-vapor atomic fluorescence using a gold-mesh pre-concentration trap. Average pre-1940 Hg accumulation in cores was not significantly different (N = 5, p= 0.14) between both regions and comparable with rates calculated for global reference sites. Post gold-rush Hg (post-1980) deposition averaged 55 ± 11.3 μg m-2 yr-1 in the northern impacted region and was more than 1.5 times higher than the post-1980 rate in Acurizal, implying a regional Hg effect of gold mining. Post-1980 Hg accumulation in Acurizal, in turn, was 2.1 times the rate reported for a global reference during that time period, suggesting an additional basin-wide effect over such reference sites. By combining our core data with assessments of the size of the impacted area and the amount of Hg released to the region since 1980, we estimated that only 2–8% of this Hg was recovered as a sedimentary signal. The remainder of the Hg was lost to the atmosphere, downstream areas, or stored in biota. Hg concentrations in surface sediments in the northern Pantanal (45.5 ± 5.5 ng gdry-1) were significantly higher than those in our reference region (29.1 ± 0.7 ng gdry-1). Hg levels in primary producers were also elevated in the northern Pantanal. Eichhornia crassipes roots contained 2.7–3.0 times more mercury than shoots in both regions and Salvinia auriculata, suggested as a biological monitor for Hg pollution, contained almost four times more mercury in the northern Pantanal (90.7 ± 9.1 ng gdry-1) than in Acurizal (24.5 ± 3.3 ng gdry-1). Plant grazers and scavengers, such as apple snails ( Pomacea sp.) and adult water beetles (Fam. Hydrophilidae), were low in Hg, confirming previous data showing that the channeling of mercury from lower to higher trophic levels along herbivorous links was inefficient compared to transfer along carnivorous links. Collections of 12–16 individuals of four species of Characidae ( Aphyocharax sp., Tetragonopterus sp., Serrasalmus spiropleura and Pygocentris nattereri) in both regions showed elevated Hg body burdens in both piranhas S. spiropleura and P. nattereri from the northern Pantanal (149.9 ± 84.2 and 302.2 ± 159.1 ng gdry-1, respectively). Fish length for each species was not statistically different between regions. P. nattereri length correlated significantly (p<0.001) with Hg content in both regions, but the slope of the regression in the northern Pantanal was 2.6 times the slope for the Acurizal collection, indicating an elevated rate of biomagnification in the Hg-impacted region. Signals of Hg use in mining can be quantified in sediment core chronologies and biological tissues, although species at different trophic levels show dissimilar impacts. Mechanisms involved in Hg magnification along food chains deserve more attention, particularly in tropical regions where the threat of chronic exposure to this neurotoxin may have the greatest implications for biodiversity. [ABSTRACT FROM AUTHOR]

Investigates the relative contribution of asbestos-related pleural thickening to lung indices and to respiratory symptoms in Brazil. Levels of height-adjusted forced vital capacity and forced expiratory volume; Shortness of breath; Spirometry; Chest imaging; Presence of parenchymal and pleural changes in lungs.