Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 98
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Environ Sci Technol ; 58(14): 6093-6104, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38545700

RESUMO

Second-generation anticoagulant rodenticides (SGARs) are widely used to control rodent populations, resulting in the serious secondary exposure of predators to these contaminants. In the United Kingdom (UK), professional use and purchase of SGARs were revised in the 2010s. Certain highly toxic SGARs have been authorized since then to be used outdoors around buildings as resistance-breaking chemicals under risk mitigation procedures. However, it is still uncertain whether and how these regulatory changes have influenced the secondary exposure of birds of prey to SGARs. Based on biomonitoring of the UK Common Buzzard (Buteo buteo) collected from 2001 to 2019, we assessed the temporal trend of exposure to SGARs and statistically determined potential turning points. The magnitude of difenacoum decreased over time with a seasonal fluctuation, while the magnitude and prevalence of more toxic brodifacoum, authorized to be used outdoors around buildings after the regulatory changes, increased. The summer of 2016 was statistically identified as a turning point for exposure to brodifacoum and summed SGARs that increased after this point. This time point coincided with the aforementioned regulatory changes. Our findings suggest a possible shift in SGAR use to brodifacoum from difenacoum over the decades, which may pose higher risks of impacts on wildlife.


Assuntos
Anticoagulantes , Rodenticidas , Animais , Anticoagulantes/análise , Rodenticidas/análise , Animais Selvagens , Aves , Reino Unido , Monitoramento Ambiental
2.
Environ Geochem Health ; 43(5): 2105-2120, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33392898

RESUMO

Conversion of agricultural fields into the industrial corridor under the State Industries Promotion Corporation of Tamil Nadu Limited (SIPCOT) necessitated the investigation of soil-borne organic contaminants. This study is the first attempt to evaluate the occurrence of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in soils from Mambakkam and Cheyyar SIPCOT belt, along the residential, industrial and agricultural transects. Concentrations of Σ28PCBs, Σ16PAHs and OCPs were in the range 0.3-9 ng/g, 33-2934 ng/g and nd-81.4 ng/g, respectively. Residential areas showed higher OCP concentrations than other site types, probably due to their frequent use in vector control programmes. DDT isomers and α-isomer of endosulfan showed low concentrations indicating past usage of these OCPs. Principal component analysis indicated that high-temperature combustion and industrial processes might be the major sources of high molecular weight PAHs, while low-temperature combustion processes might be responsible for low molecular weight PAHs. PCBs in soil were probably attributed to unaccounted combustion processes of e-waste in the region. Carcinogenic PAHs and Σ28PCBs were higher in the industrial sites. Mean Σ28PCBs at Mambakkam (4.8 ng/g) was significantly higher (p < 0.05) than that at the incipient industrial corridor Cheyyar (2.7 ng/g). Lower chlorinated PCBs (3-Cl and 4-Cl) amounted to more than half of Σ28PCBs in 75% of the sites. Total toxic equivalents (TEQs) of PAHs (total BaPeq) were found to be maximum in industrial areas. Maximum contribution to TEQs due to dioxin-like-PCBs was from PCB-157, followed by PCB-189.


Assuntos
Hidrocarbonetos Clorados/análise , Poluentes do Solo/análise , Agricultura , Dioxinas/análise , Monitoramento Ambiental , Humanos , Hidrocarbonetos Clorados/toxicidade , Índia , Indústrias , Praguicidas/análise , Praguicidas/toxicidade , Bifenilos Policlorados/análise , Bifenilos Policlorados/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Análise de Componente Principal , Medição de Risco , Solo/química , Poluentes do Solo/toxicidade
3.
Indoor Air ; 30(5): 900-913, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32090381

RESUMO

Indoor Air Quality monitoring in cultural institutions is of particular concern to protect these places and the cultural heritage content. An indoor monitoring campaign was performed in three museums in Florence (Italy) to determine the occurrence and levels of volatile organic compounds (VOCs). VOCs of interest included BTEX (benzene, toluene, ethylbenzene, xylenes), terpenes, aldehydes, organic acids, and cyclic volatile methyl siloxanes (cVMS). The most abundant VOCs in all samples analyzed were BTEX, which were strictly related to the traffic source, followed by siloxanes and terpenes. Among BTEX, toluene was always the most abundant followed by xylenes, ethylbenzene, and benzene. cVMS in exhibition rooms with the presence of visitors showed higher values compared to samples collected when the museums were closed. Terpenes showed not only the influence of vegetation-biogenic sources surrounding a museum but could also be related to the wood used for the construction of showcases and furniture and the use of cleaning products. Data obtained also showed the presence of organic acids and aldehydes whose source can be traced back to exhibits themselves and wood-based furniture. Assessing the levels of organic acids in museums is important because, over time, it can cause deterioration of the artifacts.


Assuntos
Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Monitoramento Ambiental , Museus/estatística & dados numéricos , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/análise , Aldeídos/análise , Benzeno/análise , Itália , Terpenos , Tolueno/análise , Xilenos/análise
4.
Ecotoxicol Environ Saf ; 189: 110036, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31825795

RESUMO

Self-contamination should not be underestimated when quantifying microplastics (MPs) in environmental matrices. Standardised and validated methodologies for MP sampling, extraction, and analysis are lacking. The various applications of plastics in our society have made them ubiquitous, even in clothing, rendering MP self-contamination inevitable. In the present study, we sampled lake sediment, snow, and ice, purposefully wearing red overalls composed of cotton; fibres from which we could quantify using Fourier-Transform Infrared Spectroscopy (FTIR), serving as an indication of possible self-contamination from clothes. The suitability of cotton as a representation of MP contamination was also evaluated. For all detected fibres, 25 ± 1%, 20 ± 7%, and 8 ± 6% for snow, ice, and sediment, respectively, originated from sampling attire. These findings demonstrate that self-contamination can play a significant role when quantifying MP pollution, highlighting that sampling conducted to date might have overestimated the presence of MP or even contaminated MP-free samples.


Assuntos
Vestuário , Monitoramento Ambiental/normas , Microplásticos/análise , Poluentes Químicos da Água/análise , Fibra de Algodão/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Gelo/análise , Lagos/química , Neve/química
5.
Environ Monit Assess ; 192(1): 28, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823087

RESUMO

In the original publication, Figure 5 and the related text incorrectly referred to a polyurethane fibre; however, it was a possible PET-polyurethane blend.

6.
Environ Monit Assess ; 191(11): 652, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628537

RESUMO

In the last few years, several studies have investigated microplastics (MPs) in marine ecosystems, but data monitoring and assessing the occurrence in freshwater environments are still scarce. The present study aims to investigate the occurrence, distribution, and chemical composition of MP pollution in Vesijärvi lake and Pikku Vesijärvi pond close to the city of Lahti (Finland) in winter. Sediment, snow, and ice core samples were collected near the shore of these two aquatic systems. MPs were analysed and identified by a non-destructive method using Fourier transform infrared spectroscopy (FTIR) 2D imaging. The mean concentrations of MPs detected in sediment, snow, and ice samples were 395.5 ± 90.7 MPs/kg, 117.1 ± 18.4 MPs/L, and 7.8 ± 1.2 MPs/L, respectively. FTIR results showed the predominant abundance of microplastics, such as polyamides (up to 53.3%), polyethylene and polypropylene (up to 17.1%), and natural fragments such as cellulose (up to 45.8%) and wool (up 18.8%) in the same size range. The potential release of MPs arising from stormwaters and sport and recreational activities was evidenced.


Assuntos
Monitoramento Ambiental/métodos , Microplásticos/análise , Lagoas/química , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Animais , Celulose/análise , Ecossistema , Finlândia , Lagos/química , Nylons/análise , Polietileno/análise , Polipropilenos/análise , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Environ Res ; 164: 356-366, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29567421

RESUMO

Phytoremediation is a green technique being increasingly used worldwide for various purposes including the treatment of municipal sewage sludge (MSS). Most plants proposed for this technique have high nutrient demands, and fertilization is often required to maintain soil fertility and nutrient balance while remediating the substrate. In this context, MSS could be a valuable source of nutrients (especially N and P) and water for plant growth. The aim of this study was to determine the capacity willow (Salix matsudana, cv Levante), poplar (Populus deltoides × Populus nigra, cv Orion), eucalyptus (Eucalyptus camaldulensis) and sunflower (Helianthus annuus) to clean MSS, which is slightly contaminated by trace elements (TEs) and organic pollutants, and to assess their physiological response to this medium. In particular, we aimed to evaluate the TE accumulation by different species as well as the decrease of TEs and organic pollutants in the sludge after one cropping cycle and the effect of MSS on plant growth and physiology. Since MSS did not show any detrimental effect on the biomass yield of any of the species tested, it was found to be a suitable growing medium for these species. TE phytoextraction rates depended on the species, with eucalyptus showing the highest accumulation for Cr, whereas sunflower exhibited the best performance for As, Cu and Zn. At the end of the trial, some TEs (i.e. Cr, Pb and Zn), n-alkanes and PCBs showed a significant concentration decrease in the sludge for all tested species. The highest Cr decrease was observed in pots with eucalyptus (57.4%) and sunflower (53.4%), whereas sunflower showed the highest Cu decrease (44.2%), followed by eucalyptus (41.2%), poplar (16.2%) and willow (14%). A significant decrease (41.1%) of Pb in the eucalyptus was observed. Zn showed a high decrease rate with sunflower (59.5%) and poplar (52%) and to a lesser degree with willow (35.3%) and eucalyptus (25.4%). The highest decrease in n-alkanes concentration in the sludge was found in willow (98.3%) and sunflower (97.3%), whereas eucalyptus has the lowest PCBs concentration (91.8%) in the sludge compared to the beginning of the trial. These results suggest new strategies (e.g. crop rotation and intercropping) to be adopted for a better management of this phytotechnology.


Assuntos
Biodegradação Ambiental , Salix , Esgotos , Poluentes do Solo , Oligoelementos , Solo
8.
Environ Res ; 167: 411-417, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30118960

RESUMO

The presence and accumulation of plastic waste into the marine environment are well known environmental issues. Microplastics (MPs) end up in sea waters and, due to their hydrophobicity and high surface/volume ratio, POPs tend to sorb and accumulate to their surface. The supralittoral amphipod Talitrus saltator (T. saltator) was selected to study the role of MPs in the transfer of organic pollutants and to investigate if ingested MPs could either transfer contaminants to biota or clean it adsorbing pollutants taken from the diet. T. saltator is an established POPs (Persistent Organic Pollutants) biomonitor in coastal environments and it is able to swallow microplastics in natural condition. Two laboratory experiments were performed and T. saltator was exposed to a labelled polybrominated diphenyl ether (13C-labelled BDE-47) to investigate the opposite gradient role of MPs. X Ray Micro-CT (Micro-Computed Tomography) analyses were also performed on sandhopper samples to evaluate the uptake of MPs via digestive tract. The results showed that MPs ingestion could whether transfer and remove contaminants from T. saltator, indicating a partial balance among positive and negative effects. This study has underlined MP potential double role demonstrating that MP can act both as a carrier and scavenger for the bioaccumulation of organic pollutants (i.e. PBDEs), suggesting that chemicals leaching from MPs could have a limited impact to biota.


Assuntos
Anfípodes , Monitoramento Ambiental , Éteres Difenil Halogenados/efeitos adversos , Plásticos/efeitos adversos , Poluentes Químicos da Água/efeitos adversos , Animais , Ingestão de Alimentos , Microtomografia por Raio-X
9.
Rev Environ Contam Toxicol ; 240: 1-30, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-26809717

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are consistently posing high risks to human/biota in developing countries of South Asia where domestic areas are exposed to biomass burning and commercial/industrial activities. This review article summarized the available data on PAHs occurrence, distribution, potential sources and their possible risks in the key environmental matrices (i.e., Air, Soil/Sediments, Water) from South Asian Region (SAR). Available literature reviewed suggested that PAHs concentration levels were strongly influenced by the monsoonal rainfall system in the region and it has been supported by many studies that higher concentrations were measured during the winter season as compared to summer. Biomass burning (household and brick kilns activities), open burning of solid wastes and industrial and vehicular emissions were categorized as major sources of PAHs in the region. Regional comparison revealed that the contamination levels of PAHs in the water bodies and soil/sediments in SAR remained higher relatively to the reports from other regions of the world. Our findings highlight that there is still a general lack of reliable data, inventories and research studies addressing PAHs related issues in the context of environmental and human health in SAR. There is therefore a critical need to improve the current knowledge base, which should build upon the research experience from other regions which have experienced similar situations in the past. Further research into these issues in South Asia is considered vital to help inform future policies/control strategies as already successfully implemented in other countries.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Biota , Sedimentos Geológicos/análise , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Poluentes do Solo/análise , Poluentes Químicos da Água/análise
10.
Environ Res ; 152: 26-42, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27741446

RESUMO

In this review article, we have compiled and reviewed the previously published available literature on environmental distribution, behaviour, fate and regional trends of legacy and emerging flame retardants (FRs) including brominated (BFRs), organo-phosphate (OPFRs), novel brominated flame retardants (NBFRs) and dechlorane plus (DP) in the freshwater ecosystem. Transport and fate is discussed briefly with the evidences of de-bromination, sedimentation and accumulation in biota. De-bromination of BDE-209 is considered of concern because the lower brominated congeners are more toxic and mobile thus posing increased risk to the freshwater ecosystem. The available data on temporal and spatial trends as yet, is too few to show any consistent trends, enabling only general conclusions to be drawn. There is a lack of temporal studies in Asia, while, overall the trends are mixed, with both increasing and decreasing concentrations of BFRs and OPFRs. OPFRs and NBFRs have replaced classical BFRs (polybrominated diphenyl ethers (PBDEs)) in some countries but the amount of PBDEs in the environment is still considerable. Knowledge gaps and recommendations for future research are discussed emphasizing on further monitoring, advanced analytical methodologies, and risk assessment studies to completely understand the science of flame retardants in the freshwater ecosystem.


Assuntos
Retardadores de Chama/análise , Poluentes Químicos da Água/análise , Ecossistema , Água Doce
12.
Ecotoxicol Environ Saf ; 127: 135-43, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26827277

RESUMO

The aim of this study was to evaluate the effect of traffic related polycyclic aromatic hydrocarbons (PAHs) on blood parameters of subjects, including traffic police officers (TP), drivers (DR) and control subjects (CN) with presumably different levels of exposure. We quantified the urinary 1-hydroxypyrene (1-OHPyr), α-naphthol and ß-naphthol (α- and ß-naph) as biomarkers of exposure to PAHs in relation with biomarkers of effect (Hb, MCV, PCV, PLT, RBCs), biomarkers of inflammation/infection (CRP, WBCs), oxidative stress (SOD) and oxidative DNA damage i.e. 8-hydroxy-2-deoxyguanosine (8-OHdG). Results showed that mean 1-OHPyr, α-naph and ß-naph concentrations were significantly higher in TPs (0.98, 1.55, and 1.9µmolmol-Cr(-1), respectively, p<0.05) than CNs (0.7, 0.6; 0.67µmolmol-Cr(-1), respectively, P<0.05). Furthermore, WBC and CRP were found in higher concentrations in TPs than CNs (7.04×10(3)µL(-1) and 0.95mgL(-1) vs. 5.1×10(3)µL(-1) and 0.54mgL(-1), respectively). The urinary 8-OHdG level, a biomarker of oxidative DNA damage, was higher in TPs than both CN and DR subjects (48ngmg-Cr(-1), 24ngmg-Cr(-1) and 33ngmg-Cr(-1), respectively). Self-reported health assessment indicates that, on the basis of daily time spent in the middle of heavy traffic, TPs and DRs more frequently suffered from adverse head and respiratory symptoms. The PCA analysis evidenced the impact of traffic pollution on exposure biomarkers and DNA damage. The study suggests that traffic pollution may be associated with important health risk, in particular on the respiratory system, not only for workers exposed to traffic exhausts but also for general public. Finally, vehicular air pollution in the city of Rawalpindi should be a high-priority concern for the Pakistan Government that needs to be addressed.


Assuntos
Poluição do Ar/efeitos adversos , Condução de Veículo , Exposição Ocupacional/efeitos adversos , Polícia , Emissões de Veículos/toxicidade , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Poluição do Ar/análise , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Proteína C-Reativa/análise , Estudos de Casos e Controles , Cidades , Dano ao DNA/fisiologia , Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Paquistão , Hidrocarbonetos Policíclicos Aromáticos/análise , Superóxido Dismutase/metabolismo , Emissões de Veículos/análise , Adulto Jovem
13.
Ecotoxicol Environ Saf ; 126: 219-227, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26773831

RESUMO

The present study aims to assess the arsenic (As) levels into dust samples and its implications for human health, of four ecological zones of Pakistan, which included northern frozen mountains (FMZ), lower Himalyian wet mountains (WMZ), alluvial riverine plains (ARZ), and low lying agricultural areas (LLZ). Human nail samples (N=180) of general population were also collected from the similar areas and all the samples were analysed by using ICP-MS. In general the higher levels (p<0.05) in paired dust and human nail samples were observed from ARZ and LLZ than those of other mountainous areas (i.e., WMZ and FMZ), respectively. Current results suggested that elevated As concentrations were associated to both natural, (e.g. geogenic influences) and anthropogenic sources. Linear regression model values indicated that As levels into dust samples were associated with altitude (r(2)=0.23), soil carbonate carbon density (SCC; r(2)=0.33), and population density (PD; r(2)=0.25). The relationship of paired dust and nail samples was also investigated and associations were found for As-nail and soil organic carbon density (SOC; r(2)=0.49) and SCC (r(2)=0.19) in each studied zone, evidencing the dust exposure as an important source of arsenic contamination in Pakistan. Risk estimation reflected higher hazard index (HI) values of non-carcinogenic risk (HI>1) for children populations in all areas (except FMZ), and for adults in LLZ (0.74) and ARZ (0.55), suggesting that caution should be paid about the dust exposure. Similarly, carcinogenic risk assessment also highlighted potential threats to the residents of LLZ and ARZ, as in few cases (5-10%) the values exceeded the range of US-EPA threshold limits (10(-6)-10(-4)).


Assuntos
Arsênio/análise , Carcinógenos/análise , Poeira/análise , Exposição Ambiental , Adulto , Criança , Fenômenos Ecológicos e Ambientais , Feminino , Humanos , Masculino , Unhas/química , Paquistão , Medição de Risco , Solo/química
14.
Int J Environ Health Res ; 26(1): 37-57, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25742192

RESUMO

This study presents the analyses of urinary biomarkers (1-OHPyr, α- and ß-naphthols) of polycyclic aromatic hydrocarbons (PAHs) exposure and biomarkers of effect (i.e. blood parameters) in petroleum-refinery workers (RFs) and auto-repair workers (MCs). Exposed subjects had higher concentrations of white blood cell (WBC) count than control subjects (CN) subjects (5.31 × 10(3) µL(-1) in exposed vs. 5.15 × 10(3) µL(-1) in CN subjects), while the biomarker of oxidative DNA damage (8-OHdG) was significantly higher in MCs. The exposure among these two cohorts could be influenced by the ambience of the workplaces; in fact, MCs' shops are relatively damp and enclosed workplaces in comparison with the indoor environment of refineries. PAHs in the dust samples from mechanical workshops probably originated from mixed sources (traffic exhaust and petroleum spills), while the incremental lifetime cancer risk (ILCR) for MCs showed moderate-to-low cancer risk from exposure to dust-bound PAHs. The study shows that increasing PAH exposure can be traced in MC workstations and needs to be investigated for the safety of public health.


Assuntos
Carcinógenos/toxicidade , Neoplasias/epidemiologia , Exposição Ocupacional , Indústria de Petróleo e Gás , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Biomarcadores/urina , Carcinógenos/metabolismo , Criança , Pré-Escolar , Cidades , Estudos de Coortes , Poeira/análise , Monitoramento Ambiental , Humanos , Pessoa de Meia-Idade , Neoplasias/induzido quimicamente , Paquistão/epidemiologia , Hidrocarbonetos Policíclicos Aromáticos/sangue , Hidrocarbonetos Policíclicos Aromáticos/urina , Medição de Risco , Emissões de Veículos/toxicidade , Adulto Jovem
15.
Artigo em Inglês | MEDLINE | ID: mdl-25726016

RESUMO

The influence of salt concentration in the seawater on solar orientation in Talitrus saltator and Talorchestia ugolinii was studied in a confined environment (transparent plexiglass bowls). Sodium and calcium concentrations strongly affect both sea-land orientation and the sun compass mechanism in T.saltator, whereas the behaviour of T. ugolinii is less influenced. The absence of Na(+) does not influence the sun compass mechanism, but causes an inversion in the mean direction of orientation in T. saltator. In T. ugolinii, there was no influence on the compass mechanism for solar orientation and no inversion in the directional choice. In the absence of Ca(2+), a photonegative tendency was observed for T saltator together with marked reduction in the capacity to go in any direction. However, the effect of Ca(2+) absence on the orientation capacity of T. saltator is reversible and the orientation capacity can be reduced in a few minutes. The different behaviour of the two species of sandhoppers is discussed.


Assuntos
Anfípodes/fisiologia , Orientação , Cloreto de Sódio/farmacologia , Sistema Solar , Luz Solar , Animais , Cálcio/metabolismo , Orientação/efeitos dos fármacos , Orientação/fisiologia , Orientação/efeitos da radiação , Água do Mar/química , Especificidade da Espécie
16.
Bioorg Med Chem Lett ; 25(23): 5485-9, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26525863

RESUMO

An α-carbonic anhydrase (CA, EC 4.2.1.1) has been purified from the Antarctic hemoglobinless fish Chionodraco hamatus (icefish). The new enzyme, denominated ChaCA, has a good catalytic activity for the physiologic CO2 hydration to bicarbonate reaction, similar to that of the low activity human isoform hCA I, with a kcat of 5.3×10(5) s(-1), and a kcat/Km of 3.7×10(7) M(-1) s(-1). The enzyme was inhibited in the submillimolar range by most inorganic anions (cyanate, thiocyanate, cyanide, bicarbonate, halides), whereas sulfamide, sulfamate, phenylboronic/phenylarsonic acids were micromolar inhibitors, with KIs in the range of 9-77 µM. Many clinically used drugs, such as acetazolamide, methazolamide, dorzolamide, brinzolamide, topiramate and benzolamide were low nanomolar inhibitors, with KIs in the range of 39.1-77.6 nM. As the physiology of CO2/bicarbonate transport or the Root effect in this Antarctic fish are poorly understood at this moment, such inhibition data may give a more detailed insight in the role that CAs play in these phenomena, by the use of inhibitors described here as physiologic tools.


Assuntos
Anidrases Carbônicas/isolamento & purificação , Anidrases Carbônicas/metabolismo , Peixes/fisiologia , Animais , Ânions/farmacologia , Regiões Antárticas , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/farmacologia , Ativação Enzimática/efeitos dos fármacos , Estrutura Molecular , Sulfonamidas/farmacologia
17.
J Nanosci Nanotechnol ; 15(5): 3333-47, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26504950

RESUMO

The occurrence of pharmaceuticals and other hazardous substances in surface waters and drinking water and the long-term exposure may represent a potential risk for both the environment and human health. Many studies have evidenced that conventional technologies used for wastewater treatment do not completely remove pharmaceuticals and personal care products (PPCPs) residues, which can be detected in receiving waters at concentrations ranging from few ng L(-1) until more than µg L(-1). Nanomaterials are of fundamental importance in the current research efforts to develop more efficient water treatment and remediation systems in place of conventional technologies. This review provides a comprehensive overview of the most relevant works available in literature reporting the use of nanosorbents (nanotubes and zeolites), nanofiltration (NF) and advanced oxidation processes (AOPs) for the removal of PPCPs compounds from water and wastewater. The literature review of laboratory- and pilot-scale studies have shown that nanomaterials are promising tools in environmental cleaning processes and water purification, even if more researches are necessary.


Assuntos
Produtos Domésticos/análise , Nanotecnologia/métodos , Preparações Farmacêuticas/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Águas Residuárias
18.
Environ Geochem Health ; 37(3): 515-27, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25471479

RESUMO

Aims of this study were to provide firsthand data on the incidence of trace metals in human seminal plasma and find possible correlations between levels of toxic metals and semen quality of Pakistani population. Human semen samples were collected from male partners of couples undergoing infertility assessment at the National Institute of Health Islamabad (Pakistan). We investigated seventy-five seminal plasma samples, which were further categorized into three groups (normozoospermia, oligozoospermia and azoospermia) according to WHO guidelines. The concentration of 17 different toxic metals in human seminal plasma was determined simultaneously by using Inductively coupled plasma mass spectrometry (ICP-MS). Out of 17 trace metals, Cd and Ni showed significant difference (p < 0.05) among three monitored groups. Ni and Cd concentrations in the seminal plasma were negatively correlated with sperm concentration (r = -0.26, -0.29) and motility (r = -0.33, -0.37), respectively. This study suggested that exposure of Ni and Cd is mainly related with the consumption of contaminated dietary items, including ghee (cooking oil), flour and other agri-products. In some semen samples, the concentrations of Sn, V, Cu, Pb, Cr and Hg exhibited high levels suggesting a recent human exposure to surrounding sources. In Pakistani human semen samples, the levels of trace metals were lower and/or comparable to that found in populations of other countries. The results show the first evidence of the effect of toxic metals on semen quality and male infertility in Pakistan.


Assuntos
Infertilidade Masculina/epidemiologia , Metais Pesados/análise , Análise do Sêmen , Sêmen/química , Oligoelementos/análise , Cádmio/análise , Humanos , Masculino , Níquel/análise , Paquistão/epidemiologia
19.
Environ Res ; 134: 1-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25042029

RESUMO

The present pilot study monitored for the first time volatile organic compounds (VOCs) and aerosols in domestic and occupational microenvironments in the Arctic Region. Differences between the two categories of samples are noted with domestic environments exhibiting higher concentrations of VOCs (total VOCs ranging between 106 and 584 µg m(-3)), while total particulate matter was highest in workplace non-office environments (ranging between 132 and 284 µg m(-3)). The terpenes were the most abundant class of VOCs, while a variety of other compounds exhibited 100% frequency of occurrence (i.e. naphthalene, D5-volatile methyl siloxane). Compared to results from other studies/regions, the concentrations of VOCs are considered as relatively low. Based on the results and the knowledge of the typical characteristics of the Arctic lifestyle, some important sources are identified. As this is the first study that deals with indoor air quality in the coldest region globally, it is expected that it will trigger the interest of Authorities to proceed to more detailed studies.


Assuntos
Aerossóis/análise , Poluição do Ar em Ambientes Fechados/análise , Compostos Orgânicos Voláteis/análise , Regiões Árticas , Noruega , Controle de Qualidade
20.
MethodsX ; 12: 102777, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38883588

RESUMO

The contamination of microplastics in humans is of increasing concern. Therefore, the aim of this study was to develop effective methods to determine the concentration and types of microplastics entering human digestive system. To study levels of MPs contamination in humans, an excellent indicator are stools. Indeed, stools, and thus the digestive system, can be an excellent indicator of the level of MPs contamination in humans. Hence, objective was to find effective methods to extract, quantify and characterize microplastics in stool and small intestine samples. The samples studied were human stools and pig jejunum (which has human-like characteristics). The methods were optimized by observing extraction efficiency, compatibility by Fourier-transform infrared spectroscopy (FTIR) characterization and non-deformation of the microplastics. The steps of the procedure were: • Sampling to avoid plastic contamination • Non-aggressive chemical and enzymatic digestion • Counting and characterization The methods were optimized and validated, observing recovery and repeatability. Therefore, two simple, effective methods with high analytical performance have been developed. The MPs present in the stool and intestine samples were counted by stereoscopic microscope and characterized by FTIR, finding several types of MPs such as synthetic cellulose, polyethylene, polypropylene, polystyrene, and polyethylene terephthalate, among others.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA