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1.
Sci Total Environ ; 932: 173025, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38723955

RESUMO

Contaminants of emerging concern (CECs), including microplastics, have been the focus of many studies due to their environmental impact, affecting biota and human health. The diverse land uses and occupation of watersheds are important parameters driving the occurrence of these contaminants. CECs such as pesticides, drugs, hormones, and industrial-origin substances were analyzed in urban/industrial (Atibaia) and agricultural (Preto/Turvo) watersheds located in São Paulo state, Brazil. A total of 24 CECs were investigated, and, as a result, only 5 (caffeine, carbendazim, atrazine, ametrine and 2-hydroxytrazine) were responsible for 81.73 % of the statistical difference between watersheds contamination profile. The Atibaia watershed presented considerable concentrations of caffeine (ranging from 75 to 2025 ng L-1), while carbendazim (44 to 1144 ng L-1) and atrazine (3 to 266 ng L-1) presented highest levels in Preto/Turvo watershed. In all sampling points, the cumulative potential aquatic life risk assessed by the NORMAN database indicates some level of environmental concern associated to pesticides and caffeine (risk quotient >1). Microplastics had been analyzed in both watersheds, being the white/transparent fragments in size between 100 and 250 µm the most detected in this study. The estimated abundance in the Atibaia watershed ranged from 349 to 2898 items m-3 presenting some influence of pluviosity, while in Rio Preto/Turvo ranged from 169 to 6370 items m-3, being more abundant in the dam area without a clear influence of pluviosity. In both basins, polyethylene and polypropylene were the most detected polymers, probably due to the intense use of single-use plastics in urban areas. Possibly, due to the distinct physic-chemical properties of microplastics and organic CECs, no correlations were observed between their occurrence, which makes us conclude that they have different transport mechanism, behavior, and fate in the environment.


Assuntos
Agricultura , Monitoramento Ambiental , Microplásticos , Poluentes Químicos da Água , Brasil , Poluentes Químicos da Água/análise , Microplásticos/análise , Praguicidas/análise
2.
Chemosphere ; 340: 139813, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37586495

RESUMO

Brazil maintains its position at the top of the global ranking of plastic producers, yet recycling efforts have been incipient. Recent data reveals an annual production of approximately 14 million tons of plastic waste, not accounting for the surge in the usage of plastic masks and related materials due to the COVID-19 pandemic. However, what remains largely unreported is that over half of post-consumer plastic packaging in Brazil is managed without any monitoring, and it remains unclear how this will contribute to the occurrence of plastic waste and microplastics in Brazilian freshwaters. This scenario requires the consideration of several other crucial factors. Studies have been carried out mainly in marine and estuarine waters, while data on freshwaters are lacking. Brazil has continental dimensions and the highest water availability on the planet, yet the demand for water is greatest in regions with medium to low supply. Many densely populated Brazilian urban areas face chronic flood problems, possess inadequate levels of wastewater treatment, and display inadequate solid waste management practices. Consequently, urban freshwater with tropical characteristics in Brazil presents an intriguing scenario and is complementary to the most commonly studied marine environments. In this study, we explore the nuances of pollution in Brazilian urban freshwater and discuss how various parameters, such as organic matter, suspended solids, temperature, and pH, among others, influence the behavior of microplastics and their interactions with organic and inorganic contaminants. Furthermore, we address how microplastic conditions, such as biofouling, the type of plastic, or degradation level, may impact their behavior. By analyzing how these conditions change, we propose priority themes for investigating the occurrence of microplastics in Brazilian urban freshwater systems under different degrees of human impact. Ultimately, this study aims to establish a network dedicated to standardized monitoring of microplastic pollution in Brazilian urban freshwaters.


Assuntos
COVID-19 , Poluentes Químicos da Água , Humanos , Microplásticos , Plásticos , Efeitos Antropogênicos , Brasil , Pandemias , Água Doce , Água , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Ecossistema
3.
Mar Pollut Bull ; 172: 112809, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34365157

RESUMO

This study describes the beach profile, characterizes microplastics and correlates their abundance with morphodynamics characteristics on three beaches from the state of São Paulo, Brazil. 745 particles were found in 4 m2 of sediment, mostly styrofoam. Nearly 90% of the fragments were found in Boracéia, the most dissipative beach, while less than 1% were found in Juréia beach, the most reflective one. The chemical composition of microplastics was identified by near-infrared hyperspectral imaging (HSI-NIR). The correlation between the abundance of particles and the slope plus the extension of the sand strip was high, as well as that found with the waves' height. These preliminary results indicate that there might be an intrinsic relation among the morphodynamical forces, the movement and destination of microplastics in marine environments.


Assuntos
Plásticos , Poluentes Químicos da Água , Praias , Brasil , Monitoramento Ambiental , Microplásticos , Poluentes Químicos da Água/análise
4.
Environ Pollut ; 285: 117251, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33957518

RESUMO

Microplastic pollution is a global concern theme, and there is still the need for less laborious and faster analytical methods aiming at microplastics detection. This article describes a high throughput screening method based on near-infrared hyperspectral imaging (HSI-NIR) to identify microplastics in beach sand automatically with minimum sample preparation. The method operates directly in the entire sample or on its retained fraction (150 µm-5 mm) after sieving. Small colorless microplastics (<600 µm) that would probably be imperceptible as a microplastic by visual inspection, or missed during manual pick up, can be easily detected. No spectroscopic subsampling was performed due to the high-speed analysis of line-scan instrumentation, allowing multiple microplastics to be assessed simultaneously (video available). This characteristic is an advantage over conventional infrared (IR) spectrometers. A 75 cm2 scan area was probed in less than 1 min at a pixel size of 156 × 156 µm. An in-house comprehensive spectral dataset, including weathered microplastics, was used to build multivariate supervised soft independent modelling of class analogy (SIMCA) classification models. The chemometric models were validated for hundreds of microplastics (primary and secondary) collected in the environment. The effect of particle size, color and weathering are discussed. Models' sensitivity and specificity for polyethylene (PE), polypropylene (PP), polyamide-6 (PA), polyethylene terephthalate (PET) and polystyrene (PS) were over 99% at the defined statistical threshold. The method was applied to a sand sample, identifying 803 particles without prior visual sorting, showing automatic identification was robust and reliable even for weathered microplastics analyzed together with other matrix constituents. The HSI-NIR-SIMCA described is also applicable for microplastics extracted from other matrices after sample preparation. The HSI-NIR principals were compared to other common techniques used to microplastic chemical characterization. The results show the potential to use HSI-NIR combined with classification models as a comprehensive microplastic-type characterization screening.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Imageamento Hiperespectral , Plásticos , Polietileno/análise , Poluentes Químicos da Água/análise
5.
J Hazard Mater ; 403: 123732, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32846262

RESUMO

Phenylbenzotriazoles (PBTA) can be generated unintentionally during textile dyeing factories by reduction of dinitrophenylazo dyes and their subsequent chlorination in disinfection process. Eight non-chlorinated PBTAs (non-Cl PBTA) and their related chlorinated PBTAs have been found in rivers and presented mutagenic activity. No data on their aquatic toxicity are available. In this work, two new phenylbenzotriazoles, non-Cl PBTA-9 and PBTA-9, derived from the dye C.I. Disperse Violet 93 (DV93) were synthesized and chemically/toxicologically characterized. Both compounds were more mutagenic than the parental dye in the Salmonella/microsome assay in the presence of metabolic activation (S9). Mutagenicity studies in vivo with mammals would confirm their potential hazard to humans. The two compounds were acutely toxic to Daphnia similis. We developed an analytical method to simultaneously quantify non-Cl PBTA-9, PBTA-9 and DV93 in river waters. Non-Cl PBTA-9 was found in sites under influence of textile effluents but at concentrations that do not pose risk to the aquatic life according to the P-PNEC calculated based on the acute toxicity tests. PBTA-9 was not detected in any samples analyzed. More studies on the aquatic toxicity and water occurrence of PBTAs should be conducted to verify the relevance of this class of compounds as aquatic contaminants.


Assuntos
Poluentes Químicos da Água , Água , Animais , Corantes/toxicidade , Água Doce , Humanos , Testes de Mutagenicidade , Mutagênicos , Medição de Risco , Indústria Têxtil , Têxteis , Triazóis , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
6.
Sci Total Environ ; 572: 138-146, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27494660

RESUMO

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. Samples were collected from June to September of 2011 and again during the same period in 2012. The study covered emerging contaminants of different classes, including hormones, plasticizers, herbicides, triclosan and caffeine. The analytical method for the determination of the compounds was based on solid-phase extraction followed by analysis via liquid chromatography electrospray triple-quadrupole mass spectrometry (LC-MS/MS). Caffeine, triclosan, atrazine, phenolphthalein and bisphenol A were found in at least one of the samples collected in the two sampling campaigns. Caffeine and atrazine were the most frequently detected substances in both drinking and source water. Caffeine concentrations in drinking water ranged from 1.8ngL-1 to values above 2.0µgL-1 while source-water concentrations varied from 40ngL-1 to about 19µgL-1. For atrazine, concentrations were found in the range from 2.0 to 6.0ngL-1 in drinking water and at concentrations of up to 15ngL-1 in source water. The widespread presence of caffeine in samples of treated water is an indication of the presence of domestic sewage in the source water, considering that caffeine is a compound of anthropogenic origin.


Assuntos
Água Potável/análise , Água Doce/análise , Água Subterrânea/análise , Poluentes Químicos da Água/análise , Brasil , Monitoramento Ambiental
7.
Water Res ; 98: 109-18, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27085962

RESUMO

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.e. agriculture, forestry) that incorporate a variety of OMPs into the aquatic environment, such as pesticides, pharmaceuticals and personal care products. Atrazine (herbicide), caffeine (psychotropic), diclofenac (anti-inflammatory) and triclosan (antimicrobial) in Biobío river water and in different stages of a drinking and two wastewater treatment plants downstream Biobío river were determined using solid phase extraction (SPE) and liquid chromatography/tandem mass spectrometry (LC-MS/MS) and electrospray ionization (ESI). Quantification of these four compounds showed concentrations in the range of 8 ± 2 to 55 ± 10 ng L(-1) in Biobío river water, 11 ± 2 to 74 ± 21 ng L(-1) in the drinking water treatment plant, and 60 ± 10 to 15,000 ± 1300 ng L(-1) in the wastewater treatment plants. Caffeine was used as an indicator of wastewater discharges. Because conventional water treatment technologies are not designed to eliminate some emerging organic pollutants, alternative treatment processes, UV and UV/H2O2, were employed. The transformation of atrazine, carbamazepine (antiepileptic), diclofenac and triclosan was investigated at laboratory scale. Both processes were tested at different UV doses and the Biobío river water matrix effects were evaluated. Initial H2O2 concentration used was 10 mg L(-1). Results showed that, the transformation profile obtained using UV/H2O2 at UV doses up to 900 mJ cm(-2), followed the trend of diclofenac > triclosan > atrazine > carbamazepine. Furthermore acute toxicity tests with Daphnia magna were carried out after UV/H2O2 treatments of the OMPs mixture studied. At the lower UV doses tested (300 mJ cm(-2)) a higher toxicity was observed, suggesting the formation of toxic intermediates in the course of the reaction. As expected, at higher UV doses the toxicity declined. Considering the treatment of the mixture of ATZ, CBZ, DCL and TCS with a UV dose of 1200 mJ cm(-2) and 10 mg L(-1) of H2O2 the acute toxicity results exhibits values for Daphnia magna immobilization equal to 20 and 42% evaluated after 24 and 48 h, respectively.


Assuntos
Monitoramento Ambiental , Peróxido de Hidrogênio , Animais , Humanos , Rios/química , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/química
8.
Arq Bras Oftalmol ; 72(5): 631-5, 2009.
Artigo em Português | MEDLINE | ID: mdl-20027399

RESUMO

PURPOSE: To analyze the quality of the corneas evaluated by slit lamp examination in the Eye Bank of the Hospital de Clínicas UFPR and its relation to donor age and cause of death. METHODS: Analysis of 492 corneas, evaluated in BTO HC-UFPR between August 2006 to August 2008. Each cornea was classified regarding the quality as: very good, good, regular and bad; and according to clarity, epithelial defect, stromal edema, Descemet's folds, stromal opacity, corneal scarring, endothelial density and guttata. RESULTS: The mean donor age was 42.74 years (sd=17.77 years). Among the causes of death, trauma was the most common with 46.18%, followed by cardiovascular causes with 41.86%. In relation to the cornea, 57.11% were classified as 'good', followed by 20.73% as 'regular', 16.87% as 'very good' and 5.28% as 'bad'. With the application of statistical tests based on ordinal regression model, trauma deaths corneas tend to be better, as well as those of younger patients. CONCLUSIONS: Statistically, the corneas from younger donors tend to have better graduations in the assessment, as well as the corneas from donors dead by trauma that tend to have better quality when compared to corneas from donors dead by cardiovascular and other systemic diseases.


Assuntos
Causas de Morte , Córnea/anatomia & histologia , Doadores de Tecidos/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Córnea/fisiologia , Humanos , Pessoa de Meia-Idade , Controle de Qualidade , Análise de Regressão , Estudos Retrospectivos , Adulto Jovem
9.
Arq. bras. oftalmol ; 72(5): 631-635, set.-out. 2009. graf, tab
Artigo em Português | LILACS | ID: lil-534181

RESUMO

OBJETIVO: Analisar a qualidade das córneas avaliadas em lâmpada de fenda no Banco de Tecidos Oculares do Hospital de Clínicas da Universidade Federal do Paraná (BTO HC-UFPR) relacionando com a idade e causa de óbito. MÉTODOS: Foram analisadas retrospectivamente fichas de avaliações padronizadas de 492 córneas, avaliadas no BTO HC-UFPR, do período de agosto de 2006 a agosto de 2008. Cada córnea avaliada foi classificada em relação a sua qualidade em: Muito bom, bom, regular e ruim; mediante os seguintes fatores: claridade da córnea, edema epitelial, defeito epitelial, edema estromal, dobras de Descemet, opacidade estromal, cicatrizes corneanas, densidade endotelial e guttata. RESULTADOS: A idade média dos doadores foi de 42,74 anos (dp=17,77). Dentre as causas de óbito, a mais comum foi trauma com 46,18 por cento, seguindo por causas cardiovasculares com 41,86 por cento. Na avaliação da córnea, foram classificadas: 57,11 por cento como "bom", seguido por 20,73 por cento "regular", 16,87 por cento "muito bom" e 5,28 por cento "ruim". Com aplicação de testes estatísticos baseados em modelo de regressão ordinal verificou-se que as córneas provenientes de mortes por traumas tendem a ser melhores, bem como aquelas de pacientes mais jovens. CONCLUSÕES: Estatisticamente, córneas de doadores mais jovens tendem a ter melhores graduações na avaliação, bem como córneas provenientes de doadores com morte por trauma tendem a ser de melhor qualidade quando comparadas com as provenientes de mortes por doenças cardiovasculares e outras doenças sistêmicas.


PURPOSE: To analyze the quality of the corneas evaluated by slit lamp examination in the Eye Bank of the Hospital de Clínicas UFPR and its relation to donor age and cause of death. METHODS: Analysis of 492 corneas, evaluated in BTO HC-UFPR between August 2006 to August 2008. Each cornea was classified regarding the quality as: very good, good, regular and bad; and according to clarity, epithelial defect, stromal edema, Descemet's folds, stromal opacity, corneal scarring, endothelial density and guttata. RESULTS: The mean donor age was 42.74 years (sd=17.77 years). Among the causes of death, trauma was the most common with 46.18 percent, followed by cardiovascular causes with 41.86 percent. In relation to the cornea, 57.11 percent were classified as "good", followed by 20.73 percent as "regular", 16.87 percent as "very good" and 5.28 percent as "bad". With the application of statistical tests based on ordinal regression model, trauma deaths corneas tend to be better, as well as those of younger patients. CONCLUSIONS: Statistically, the corneas from younger donors tend to have better graduations in the assessment, as well as the corneas from donors dead by trauma that tend to have better quality when compared to corneas from donors dead by cardiovascular and other systemic diseases.


Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Causas de Morte , Córnea/anatomia & histologia , Doadores de Tecidos/estatística & dados numéricos , Distribuição por Idade , Fatores Etários , Córnea/fisiologia , Controle de Qualidade , Análise de Regressão , Estudos Retrospectivos , Adulto Jovem
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