Occupational airborne contamination in South Brazil: 2. Oxidative stress detected in the blood of workers of incineration of hospital residues

One of the most useful methods for elimination of solid residues of health services (SRHS) is incineration. However, it also provokes the emission of several hazardous air pollutants such as heavy metals, furans and dioxins, which produce reactive oxygen species and oxidative stress. The present study, which is parallel to an accompanied paper (Avila Jr. et al., this issue), investigated several enzymatic and non-enzymatic biomarkers of oxidative stress in the blood (contents of vitamin E, lipoperoxidation = TBARS, reduced glutathione = GSH, oxidized glutathione = GSSG, and activities of glutathione S-transferase = GST, glutathione reductase = GR, glutathione peroxidase = GPx, catalase = CAT and superoxide dismutase = SOD), in three different groups (n = 20 each) exposed to airborne contamination associated with incineration of SRHS: workers directly (ca. 100 m from the incinerator) and indirectly exposed (residents living ca. 5 km the incineration site), and controls (non-exposed subjects). TBARS and GSSG levels were increased whilst GSH, TG and alpha-tocopherol contents were decreased in workers and residents compared to controls. Increased GST and CAT activities and decreased GPx activities were detected in exposed subjects compared to controls, while GR did not show any difference among the groups. In conclusion, subjects directly or indirectly exposed to SRHS are facing an oxidative insult and health risk regarding fly ashes contamination from SRHS incineration.

Antioxidant therapy attenuates oxidative stress in the blood of subjects exposed to occupational airborne contamination from coal mining extraction and incineration of hospital residues

Coal mining and incineration of solid residues of health services (SRHS) generate several contaminants that are delivered into the environment, such as heavy metals and dioxins. These xenobiotics can lead to oxidative stress overgeneration in organisms and cause different kinds of pathologies, including cancer. In the present study the concentrations of heavy metals such as lead, copper, iron, manganese and zinc in the urine, as well as several enzymatic and non-enzymatic biomarkers of oxidative stress in the blood (contents of lipoperoxidation = TBARS, protein carbonyls = PC, protein thiols = PT, alpha-tocopherol = AT, reduced glutathione = GSH, and the activities of glutathione S-transferase = GST, glutathione reductase = GR, glutathione peroxidase = GPx, catalase = CAT and superoxide dismutase = SOD), in the blood of six different groups (n = 20 each) of subjects exposed to airborne contamination related to coal mining as well as incineration of solid residues of health services (SRHS) after vitamin E (800 mg/day) and vitamin C (500 mg/day) supplementation during 6 months, which were compared to the situation before the antioxidant intervention (Avila et al., Ecotoxicology 18:1150-1157, 2009; Possamai et al., Ecotoxicology 18:1158-1164, 2009). Except for the decreased manganese contents, heavy metal concentrations were elevated in all groups exposed to both sources of airborne contamination when compared to controls. TBARS and PC concentrations, which were elevated before the antioxidant intervention decreased after the antioxidant supplementation. Similarly, the contents of PC, AT and GSH, which were decreased before the antioxidant intervention, reached values near those found in controls, GPx activity was reestablished in underground miners, and SOD, CAT and GST activities were reestablished in all groups. The results showed that the oxidative stress condition detected previously to the antioxidant supplementation in both directly and indirectly subjects exposed to the airborne contamination from coal dusts and SRHS incineration, was attenuated after the antioxidant intervention.

Determination of cadmium and lead in cetacean Dolphinidae tissue from the coast of Bahia state in Brazil by GFAAS

In the present study, cadmium and lead in the muscle, lung, liver and kidney of dolphins (Sotalia guianensis and Stenella clymene) of the Bahia coast in the northwest of Brazil were determined by graphite furnace atomic absorption spectrometry. Samples were digested using a diluted oxidant mixture (HNO(3) + H(2)O(2)) with a microwave heating program performed in five steps. The optimized temperatures and chemical modifier for the pyrolysis and atomization were 700 degrees C, 1400 degrees C and Pd plus Mg for Cd, and 900 degrees C, 1800 degrees C and NH(4)H(2)PO(4) for Pb, respectively. Characteristic masses and limits of detections (n = 20, 3 sigma) for Cd and Pb were 1.6 and 9.0 pg and 0.82 ng g(-1) and 0.50 ng g(-1), respectively. Repeatability ranged from 0.87 to 8.22% for Cd and 4.31 to 8.09% for Pb. The found concentrations presented no statistical differences at the 95% confidence level when compared with the ICP OES methods. Addition and recovery tests were also performed and the results ranged between 87 and 112% for both elements. Samples of cetacean Dolphinidae (S. guianensis and S. clymene) were analyzed, and the higher concentrations ranged from 0.09 to 46.2 mu g g(-1) for Cd and 0.04 to 0.47 mu g g(-1) for Pb in liver, and from 0.133 to 277 mu g g(-1) for Cd in the kidney. (C) 2010 Elsevier By. All rights reserved.

EVALUATION OF METAL TOXICITY BY A MODIFIED METHOD BASED ON THE FUNGUS GERRONEMA VIRIDILUCENS BIOLUMINESCENCE IN AGAR MEDIUM

Metal cation toxicity to basidiomycete fungi is poorly understood, despite its well-known importance in terrestrial ecosystems. Moreover, there is no reported methodology for the routine evaluation of metal toxicity to basidiomycetes. In the present study, we describe the development of a procedure to assess the acute toxicity of metal cations (Na(+), K(+), Li(+), Ca(2+), Mg(2+), Co(2+), Zn(2+), Ni(2+), Mn(2+), Cd(2+), and Cu(2+)) to the bioluminescent basidiomycete fungus Gerronema viridilucens. The method is based on the decrease in the intensity of bioluminescence resulting from injuries sustained by the fungus mycelium exposed to either essential or nonessential metal toxicants. The assay described herein enables LIS to propose a metal toxicity series to Gerronenia viridilucens based on data obtained from the bioluminescence intensity (median effective concentration [EC50] values) versus metal concentration: Cd(2+) > Cu(2+) > Mn(2+) approximate to Ni(2+) approximate to Co(2+) > Zn(2+) > Mg(2+) > Li(+) > K(+) approximate to Na(+) > Ca(2+), and to shed some li-ht on the mechanism of toxic action of metal cations to basidiomycete fungi. Environ. Toxicol. Chem. 2010;29:320-326. (C) 2009 SETAC

OZONATION OF SEDIMENTS FROM AN URBAN LAKE: AN EXPLORATORY INVESTIGATION

An exploratory investigation was conducted on the effects of application of ozone on the removal of organic and inorganic contaminants and the reduction of settleable solids in urban lake sediments. Homogenized sediment samples were treated in a batch reactor with an external recirculation loop and ozone feed from a Venturi injector. The ozone generating system was fed with ambient air with small footprint and operational simplicity. Ozone mass application (g/h) and contact time (min) were varied over wide ranges during testing. The effects of the ozone mass applied per unit time and the contact time on contaminant removal efficiencies were analyzed and a trade-off between the costs of ozonation and of solids treatment and disposal was proposed. The minimum ozone mass application required for total contaminant removal apparently depended on the type of organic contaminant present. An apparent influence of inorganic contaminant speciation on the removal efficiency was found and discussed.

Automated two-dimensional separation flow system with electrochemical preconcentration, stripping, capillary electrophoresis and contactless conductivity detection for trace metal ion analysis

This paper describes the automation of a fully electrochemical system for preconcentration, cleanup, separation and detection, comprising the hyphenation of a thin layer electrochemical flow cell with CE coupled with contactless conductivity detection (CE-C(4)D). Traces of heavy metal ions were extracted from the pulsed-flowing sample and accumulated on a glassy carbon working electrode by electroreduction for some minutes. Anodic stripping of the accumulated metals was synchronized with hydrodynamic injection into the capillary. The effect of the angle of the slant polished tip of the CE capillary and its orientation against the working electrode in the electrochemical preconcentration (EPC) flow cell and of the accumulation time were studied, aiming at maximum CE-C(4)D signal enhancement. After 6 min of EPC, enhancement factors close to 50 times were obtained for thallium, lead, cadmium and copper ions, and about 16 for zinc ions. Limits of detection below 25 nmol/L were estimated for all target analytes but zinc. A second separation dimension was added to the CE separation capabilities by staircase scanning of the potentiostatic deposition and/or stripping potentials of metal ions, as implemented with the EPC-CE-C(4)D flow system. A matrix exchange between the deposition and stripping steps, highly valuable for sample cleanup, can be straightforwardly programmed with the multi-pumping flow management system. The automated simultaneous determination of the traces of five accumulable heavy metals together with four non-accumulated alkaline and alkaline earth metals in a single run was demonstrated, to highlight the potentiality of the system.

Methylmercury localization in Danio rerio retina after trophic and subchronic exposure: A basis for neurotoxicology

Methylmercury is a known neurotoxic organometal which affects visual functions and few studies concerns to wild fish are available. The autometallography mercury distribution in the retina of Danio rerio was mapped using light and electron microscopy. Abundant mercury deposits were found in the photoreceptor layer (outer and inner segments of the photoreceptors) and in the inner and outer nuclear layers. Occasionally, the presence of mercury deposits in plexiform layers was observed and very rarely in the ganglion cell layer. Also the occurrence of mercury deposits in cells from the disc region was observed, but not in the nerve fiber layer. An interesting difference was found between mercury accumulation in the central and peripheral regions of the retina. These results demonstrate that mercury after trophic exposure to Danio rerio is able to cross the blood-retina barrier and accumulate in the cells of the retina even under subchronic exposure. (C) 2010 Elsevier Inc. All rights reserved.

Tungmetallers påverkan på bottenfaunans artsammansättning i sjön Tisken

The purpose of this study was to investigate how elevated levels of heavy metals affect the faunal species composition, abundance and species-diversity. The bentic macroinvertebrate fauna in the highly polluted lake Tisken was compared with the bentic macroinvertebrate fauna in the unpolluted lake Varpan. Mine wastes account for most of the metal that is discharged into Tisken. The hypotheses was that the heavy metal pollutions in lake Tisken influenced the species composition, abundance and diversity of the macroinvertebrates. Twenty samples were taken in both sites. The invertebrates were collected with a bag net and a plastic cylinder one meter from the shoreline. The invertebrates in the forty samples were classified and statistical analyses were made.Some taxa, common at undisturbed sites, were missing at metal polluted sites. Mayfly larvae, Ephemeroptera, were only found in Varpan. Surprisingly, more taxa were found in the polluted lake Tisken (23 taxa) compared to the unpolluted Varpan (19 taxa). However, the abundance of macroinvertebrates in Varpan (291 individuals) was higher than in Tisken (242 individuals).

Desenvolvimento e validação de método analítico para quantificação da boldina em peumus boldus mol. (monimiaceae) e avaliação preliminar de sua estabilidade

Peumus boldus Molina (Monimiaceae) é uma árvore comum e abundante no Chile, e suas folhas são amplamente empregadas pela medicina tradicional para o tratamento de uma variedade de afecções do sistema digestivo e hepatobiliar. Seus principais constituintes químicos são alcalóides do tipo aporfínicos, sendo a boldina seu maior e mais característico representante, cujas propriedades antioxidantes são extensivamente relatadas na literatura, servindo desta forma como marcador químico para a espécie. Com o objetivo de contribuir com parâmetros de controle de qualidade, um estudo botânico macro e microscópico das folhas e do pó da espécie foi realizado. Características morfológicas, identificadas pela análise macroscópica, como pilosidade, tipologia dos tricomas, proeminência ao redor da base dos tricomas e aparência do bordo, e características microscópicas como estômatos anomocíticos, folha hipoestomática e ocorrência de cristais de oxalato de cálcio denotam valor taxonômico. Parâmetros farmacopéicos como cinzas totais e perda por dessecação foram determinados, e um método de quantificação da boldina foi desenvolvido e validado utilizando a CLAE. O limite mínimo de boldina observado na análise de 10 amostras adquiridas foi de aproximadamente 0,016%. A fim de avaliarse o comportamento de seus constituintes químicos frente a variações de temperatura e umidade, realizou-se estudo de estabilidade acelerada (40ºC ± 2ºC / 75% ± 5% U.R.). A degradação máxima de boldina foi observada após 90 dias em câmara climática chegando a aproximadamente 52%. A reação de degradação sugerida foi de segunda ordem, e o tempo de vida útil e meia-vida calculados foram de aproximadamente 18 dias e 165 dias, respectivamente. Por fim, realizou-se a quantificação de alguns metais pesados nas folhas da espécie, que decresceram na ordem de Fe> Mn> Cu> Ni, sendo que Pb, Cr e Co tiveram níveis abaixo do limite de detecção de 5 μg/g.

New bacterial cellulose nanocomposites prepared by in situ radical polymerization of methacrylate monomers

Bacterial cellulose/polymethacrylate nanocomposites have received attention in numerous areas of study and in a variety of applications. The attractive properties of methacrylate polymers and bacterial cellulose, BC, allow the synthesis of new nanocomposites with distinct characteristics. In this study, BC/poly(glycidylmethacrylate) (BC/PGMA) and BC/poly(ethyleneglycol)methacrylate (BC/PPEGMA) nanocomposites were prepared through in situ free radical polymerization of GMA and PEGMA, respectively. Ammonium persulphate (APS) was used as an initiator and N,N’methylenebisacrilamide (MBA) was used as a crosslinker in BC/PGMA. Chemical composition, morphology, thermal stability, water absorption, mechanic and surface properties were determined through specific characterization techniques. The optimal polymerization was obtained at (1:2) for BC/PGMA, (1:2:0.2) ratio for BC/GMA/MBA and (1:20) for BC/PPEGMA, with 0.5% of initiator at 60 ºC during 6 h. A maximum of 67% and 87% of incorporation percentage was obtained, respectively, for the nanocomposites BC/PGMA/MBA and BC/PPEGMA. BC/PGMA nanocomposites exhibited an increase of roughness and compactation of the three-dimensional structure, an improvement in the thermal and mechanical properties, and a decrease in their swelling ability and crystallinity. On the other hand, BC/PPEGMA showed a decrease of stiffness of three-dimensional structure, improvement in thermal and mechanical properties, an increase in their swelling ability and a decrease the crystallinity. Both BC/polymethacrylate nanocomposites exhibited a basic surface character. The acid treatment showed to be a suitable strategy to modifiy BC/PGMA nanocomposites through epoxide ring-opening reaction mechanism. Nanocomposites became more compact, smooth and with more water retention ability. A decrease in the thermal and mechanical proprieties was observed. The new nanocomposites acquired properties useful to biomedical applications or/and removal of heavy metals due to the presence of functional groups.

Vermiculitas tratadas quimicamente na obtenção de sólidos microporosos como precursores para híbridos inorgânico-orgânicos com aplicações adsortivas

ALVES, Ana paula Melo. Vermiculitas tratadas quimicamente na obtenção de sólidos microporosos como precursores para híbridos inorgânico-orgânicos com aplicações adsortivas. 2009. 124 f. Tese (Doutorado em Quimica) - Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraíba, João Pessoa, PB, 2009.

Diagnóstico ecotoxicológico dos efluentes lançados no complexo estuarino do Jundiaí/Potengi, Natal/RN

Untreated effluents that reach surface water affect the aquatic life and humans. This study aimed to evaluate the wastewater s toxicity (municipal, industrial and shrimp pond effluents) released in the Estuarine Complex of Jundiaí- Potengi, Natal/RN, through chronic quantitative e qualitative toxicity tests using the test organism Mysidopsis Juniae, CRUSTACEA, MYSIDACEA (Silva, 1979). For this, a new methodology for viewing chronic effects on organisms of M. juniae was used (only renewal), based on another existing methodology to another testorganism very similar to M. Juniae, the M. Bahia (daily renewal).Toxicity tests 7 days duration were used for detecting effects on the survival and fecundity in M. juniae. Lethal Concentration 50% (LC50%) was determined by the Trimmed Spearman-Karber; Inhibition Concentration 50% (IC50%) in fecundity was determined by Linear Interpolation. ANOVA (One Way) tests (p = 0.05) were used to determinate the No Observed Effect Concentration (NOEC) and Low Observed Effect Concentration (LOEC). Effluents flows were measured and the toxic load of the effluents was estimated. Multivariate analysis - Principal Component Analysis (PCA) and Correspondence Analysis (CA) - identified the physic-chemical parameters better explain the patterns of toxicity found in survival and fecundity of M. juniae. We verified the feasibility of applying the only renewal system in chronic tests with M. Juniae. Most efluentes proved toxic on the survival and fecundity of M. Juniae, except for some shrimp pond effluents. The most toxic effluent was ETE Lagoa Aerada (LC50, 6.24%; IC50, 4.82%), ETE Quintas (LC50, 5.85%), Giselda Trigueiro Hospital (LC50, 2.05%), CLAN (LC50, 2.14%) and COTEMINAS (LC50, IC50 and 38.51%, 6.94%). The greatest toxic load was originated from ETE inefficient high flow effluents, textile effluents and CLAN. The organic load was related to the toxic effects of wastewater and hospital effluents in survival of M. Juniae, as well as heavy metals, total residual chlorine and phenols. In industrial effluents was found relationship between toxicity and organic load, phenols, oils and greases and benzene. The effects on fertility were related, in turn, with chlorine and heavy metals. Toxicity tests using other organisms of different trophic levels, as well as analysis of sediment toxicity are recommended to confirm the patterns found with M. Juniae. However, the results indicate the necessity for implementation and improvement of sewage treatment systems affluent to the Potengi s estuary

Influência do lodo de ETE na massa para fabricação de cerâmica vermelha

The WTP produce many kinds of residue on your treatment stages, but the sludge is the more problematic from the final disposition point view. The actual rate of residue production deriving from technological evolution and the crescent population needs prevents the subtle equilibrium generation between consumption and recycling/reuse, creating problems of pollution resulting from inappropriate management of residues. Thus, is necessary achieve a new equilibrium between the grow from raw materials and energy and the residue generation. This equilibrium should be achieved by technical and economic feasibility of environmental supported models through recycling and reuse. The red ceramic industry stand out in residue absorption question as raw material due their clay mass heterogeneity, constituted by clay minerals and non-clay minerals with wide mineralogical variation, allowing residue inclusion which act like plastic or non-plastic materials, contributing to retain heavy metals contained in residues in the vitreous mass formed during the burning of the ceramic bodies. This work propose the study of the influence of incorporation of 25 wt.% sludge from wastewater treatment plant, according preliminary results, in the mass to produce ceramic bodies. The raw materials was characterized through chemical composition analyses by XRF, mineralogical analyses by XRD, thermal analyses by TG and DTA, Atterberg limits and thermodilatometry. Subsequently was composed the mass with 75 wt.% of clay and 25 wt.% of dried wastewater sludge from UFRN WWTP. Samples with 6,0 x 2,0 x 0,5 cm was produced with unidirectional compacting under pressure of 20MPa and burned in temperatures between 950 and 1,200ºC. After fired, the ceramic bodies have been submitted to physical and mechanical analyses through the measure of firing shrinkage, water absorption, density, apparent porosity and flexural strength; crystallographic analyses through XRD and microstructure analyses by SEM. The technological properties obtained was satisfactory to production of roof tiles with 25 wt.% at 1,200 ºC, but the production of others products at lower temperatures was not feasible

Obtenção de filtro cerâmico a partir da diatomita e casca de arroz carbonizada visando tratamento de efluente têxtil

The effluents released by the textile industry have high concentrations of alkali, carbohydrates, proteins, in addition to colors containing heavy metals. Therefore, a filter was prepared aiming primarily to the removal of color. In order to prepare this filter, rice hulls and diatomite were used, which have in their structure, basically amorphous hydrated silica. The silica exists in three crystalline forms: quartz, tridymite and cristobalite. In accordance with the above considerations, this study was divided into two stages; the first corresponds to the preparation of the filter and the second to carry out the tests in the effluent/filter in order to verify the efficiency of the color removal. First, the raw material was subjected to a chemical analysis and XRD, and then the diatomite was mixed, via humid, with a planetarium windmill with 20 %, 40 %, 60 % and 80 % of rice husk ash. To the mixture, 5 % carboxymethylcellulose (CMC) was added as a binder at room temperature. The samples were uniaxially compacted into metallic matrix of 0.3 x 0.1 cm² of area at a pressure of 167 MPa by means of hydraulic press and then sintered at temperatures of 1,000 °C, 1,200 °C and 1,400 °C for 1 h and submitted to granulometry test using laser, linear retraction, water absorption, apparent porosity and resistance to bending, DTA, TMA and XRD. To examine the pore structure of the samples scanning electron microscope (SEM) was used. Also tests were carried out in a mercury porosimeter to verify the average size of the pores and real density of the samples. In the second stage, samples of the effluent were collected from a local industry, whose name will be preserved, located in Igapó, in the State of Rio Grande do Norte - RN. The effluent was first pretreated before filtration and then subjected to a treatment of flotation. The effluent was then characterized before and after filtration, with parameters of color, turbidity, suspended solids, pH, chemical and biochemical oxygen demand (COD and BOD). Thus, through the XRD analysis the formation of cristobalite α in all samples was observed. The best average size of pore was found to be 1.75 μm with 61.04 % apparent porosity, thus obtaining an average 97.9 % color removal and 99.8 % removal of suspended solid

Avaliação da correlação entre os parâmetros, carbono orgânico total e elementos tóxicos, em solo de um posto de serviço e revenda de combustíveis

Today a major responsibility for the contamination of soil and groundwater and surface water are establishments known as gas stations of fuel which has attracted increasing attention from both the general population as the state agencies of environmental control due to leaks in storage tanks and mainly to disruption of pipe corrosion of tanks and pumping. Other services, like oil changes and car wash are also causes for concern in this type of establishment. These leaks can cause or waste produced, and the contamination of aquifers, serious health problems and public safety, since most of these stations located in urban areas. Based on this, the work was to evaluate soil contamination of a particular service station and fuel sales in the city of Natal, through the quantification of heavy metals like Cd, Cu, Cr, Ni, Pb, Zn of total organic carbon (TOC) and organic matter using different techniques such as optical emission spectrometry with inductively coupled plasma source (ICP OES), Total Organic Carbon analyzer and gravimetric analysis respectively. And also to characterize the soil through particle size analysis. Samples were taken in 21 georeferenced points and collected in the same period. The soils sampled in sampling stations P3, P5, P6, P10, P11, P12, P13, P14, P15, P17, P18 and P20 showed the smallest size fractions ranging from fine sand to medium sand. The other study sites ranged from fine sand to medium sand, except the point P8 showed that only the type size medium sand and P19, indicating a particle size of the coarse type. The small correlation of organic matter with the elements studied in this work suggests that these are not of anthropogenic origin but geochemical support