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1.
Environ Sci Technol ; 58(15): 6772-6780, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38577774

RESUMO

The quality of chemical analysis is an important aspect of passive sampling-based environmental assessments. The present study reports on a proficiency testing program for the chemical analysis of hydrophobic organic compounds in silicone and low-density polyethylene (LDPE) passive samplers and hydrophilic compounds in polar organic chemical integrative samplers. The median between-laboratory coefficients of variation (CVs) of hydrophobic compound concentrations in the polymer phase were 33% (silicone) and 38% (LDPE), similar to the CVs obtained in four earlier rounds of this program. The median CV over all rounds was 32%. Much higher variabilities were observed for hydrophilic compound concentrations in the sorbent: 50% for the untransformed data and a factor of 1.6 after log transformation. Limiting the data to the best performing laboratories did not result in less variability. Data quality for hydrophilic compounds was only weakly related to the use of structurally identical internal standards and was unrelated to the choice of extraction solvent and extraction time. Standard deviations of the aqueous concentration estimates for hydrophobic compound sampling by the best performing laboratories were 0.21 log units for silicone and 0.27 log units for LDPE (factors of 1.6 to 1.9). The implications are that proficiency testing programs may give more realistic estimates of uncertainties in chemical analysis than within-laboratory quality control programs and that these high uncertainties should be taken into account in environmental assessments.


Assuntos
Polietileno , Poluentes Químicos da Água , Polietileno/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Compostos Orgânicos , Silicones
2.
J Pediatr Genet ; 11(3): 232-235, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35990036

RESUMO

Chronic pancreatitis (CP) is a rare disease in children. We describe the first case of a 3-year-old Caucasian patient with CP with the presence of a homozygous pathogenic variant c.194 + 2T > C in serine protease inhibitor, Kazal type 1 ( SPINK1 ) and pancreas divisum.

3.
Environ Toxicol Chem ; 41(8): 1885-1902, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35512673

RESUMO

We evaluated the precision and accuracy of multilaboratory measurements for determining freely dissolved concentrations (Cfree ) of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in sediment porewater using polydimethylsiloxane (PDMS) and low-density polyethylene (LDPE) polymeric samplers. Four laboratories exposed performance reference compound (PRC) preloaded polymers to actively mixed and static ex situ sediment for approximately 1 month; two laboratories had longer exposures (2 and 3 months). For Cfree results, intralaboratory precision was high for single compounds (coefficient of variation 50% or less), and for most PAHs and PCBs interlaboratory variability was low (magnitude of difference was a factor of 2 or less) across polymers and exposure methods. Variability was higher for the most hydrophobic PAHs and PCBs, which were present at low concentrations and required larger PRC-based corrections, and also for naphthalene, likely due to differential volatilization losses between laboratories. Overall, intra- and interlaboratory variability between methods (PDMS vs. LDPE, actively mixed vs. static exposures) was low. The results that showed Cfree polymer equilibrium was achieved in approximately 1 month during active exposures, suggesting that the use of PRCs may be avoided for ex situ analysis using comparable active exposure; however, such ex situ testing may not reflect field conditions. Polymer-derived Cfree concentrations for most PCBs and PAHs were on average within a factor of 2 compared with concentrations in isolated porewater, which were directly measured by one laboratory; difference factors of up to 6 were observed for naphthalene and the most hydrophobic PAHs and PCBs. The Cfree results were similar for academic and private sector laboratories. The accuracy and precision that we demonstrate for determination of Cfree using polymer sampling are anticipated to increase regulatory acceptance and confidence in use of the method. Environ Toxicol Chem 2022;41:1885-1902. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Assuntos
Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Dimetilpolisiloxanos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Humanos , Naftalenos , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Polietileno/química , Polímeros , Poluentes Químicos da Água/análise
4.
J Hazard Mater ; 425: 127901, 2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-34906870

RESUMO

The aim of this work was to evaluate the adsorption capacity and mechanism of two antiviral drugs AVDs (lopinavir (LOP) and ritonavir (RIT)) on three various sewage sludges (SSLs). The results showed that SSLs differed in the structure and chemical composition and LOP and RIT had a high affinity to the studied SSLs (Kd in ranges 2076-3449 L/kg). The adsorption capacities differed between SSLs and ranged 7.55-8.71 mg/g (RIT) and 8.10-8.64 mg/g (LOP). The Freundlich model provided a best fitting of adsorption isotherms of all AVDs-SSLs. The adsorption kinetics were best described by pseudo-second order kinetic model. The adsorption of LOP and RIT on SSLs was exothermic, spontaneous, and thermodynamically feasible. The sorption of LOP and RIT to SSLs was complex due to the diverse chemical composition of SSLs and the differences in the chemical structure of AVDs. Analysis of binary solution of both AVDs showed the competition effect between AVDs and a decrease in adsorption efficiency (3-17%) compared to single solutions. The amount of desorbed AVDs from all SSLs was low (less than 15%). The findings of the present work are significant in the prediction of fate and persistence of AVDs on SSLs in the context of their further transmission and possible environmental contamination.


Assuntos
Esgotos , Poluentes Químicos da Água , Adsorção , Antivirais , Cinética , Lopinavir , Ritonavir , Poluentes Químicos da Água/análise
5.
Water Res ; 185: 116259, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798889

RESUMO

Passive sampling and bioaccumulation assessments were used to evaluate the performance of activated carbon (AC) remediation of polychlorinated biphenyl (PCB) contaminated sediment offshore in Parcel F of the former Hunters Point Naval Shipyard (HPNS) (San Francisco, California). Two different composite AC materials, AquaGate+PAC™ (86 tons) and SediMite™ (24 tons) were placed on the sediment surface covering an area of 3200 m2. PCB tissue concentrations in the clam Macoma nasuta were reduced 75 to 80% in pilot amendment areas after 8 months and 84-87% in non-lipid normalized tissues after 14 months during in situ monitoring, confirming the effectiveness of the AC at reducing bioavailability of the PCBs. Polydimethylsiloxane (PDMS) passive samplers were applied to evaluate and monitor freely dissolved concentrations (Cfree) of PCBs in sediment porewater before AC placement (i.e., during baseline) and at 8 months, 14 months and 26 months following placement. Although AC composite materials were placed only at the surface, 80% reductions were observed to a depth of 16 cm after 8 months and up to 26 cm after 26 months in AquaGate+PAC treatment area. Total PCB porewater concentrations in surface sediments (1-6 cm) were reduced 89 and 91% in the AquaGate+PAC and SediMite areas during final sampling. Ex situ passive sampling showed porewater concentrations 2-5 times larger than in situ measurements due to the absence of hyporheic exchange in laboratory measurements and near equilibration between sediment and porewater. Estimated post placement ex situ porewater concentrations were more consistent with a model of bioaccumulation using the octanol-water partition coefficient (KOW) as a bioaccumulation factor leading to a hypothesis that the bioaccumulation factor in the deposit feeding clam is better estimated by equilibrium ex situ porewater measurements.


Assuntos
Bifenilos Policlorados , Poluentes Químicos da Água , Animais , Disponibilidade Biológica , Carvão Vegetal , Monitoramento Ambiental , Sedimentos Geológicos , Bifenilos Policlorados/análise , São Francisco , Poluentes Químicos da Água/análise
6.
Sci Total Environ ; 737: 139726, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32563112

RESUMO

Recontamination of sediments by stormwater is a major concern when evaluating the potential effectiveness of sediment remediation. Stormwater and sediment sampling were conducted in a mixed-use watershed at Paleta Creek in San Diego, CA to evaluate methods for assessing sediment recontamination by metals. Size-segregated stormwater contaminant loads with simultaneous receiving water and sediment measurements were used to identify dominant sources and contaminants with respect to their impact on sediment recontamination. Most of the stormwater contaminant loads of Cd, Cu, Pb, and Zn were associated with residential and highway sources from the upstream portions of the watershed and As, Ni and Hg were more significantly influenced by the downstream area of the watershed. Cd was strongly associated with large particles (>63 µm) and observed to settle in near shore areas with some attenuation due to mixing and dilution. Cu, in contrast, was associated more with the filtered fraction (<0.45 µm) and clay fraction (0.45-5 µm), resulting in less near shore sediment recontamination. Depositing sediment and other metals, particularly Cu and Hg, exhibited greater accumulation in settling traps than could be attributed to stormwater loads indicating the importance of other sources or resuspension of bay sediments on surficial sediment concentrations. Pb, Zn, Ni, and As showed influences of both stormwater and other sources. The study showed that measurement of size-segregated stormwater contaminant mass and concentrations combined with simultaneous measurements of deposition in sediment traps could differentiate between recontamination by stormwater and that of other sources.

7.
Environ Toxicol Chem ; 39(1): 229-239, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622513

RESUMO

To assess potential impacts on receiving systems, associated with storm water contaminants, laboratory 10-d amphipod (Eohaustorius estuarius) survival toxicity tests were performed using intact sediment cores collected from Paleta Creek (San Diego Bay, CA, USA) on 5 occasions between 2015 and 2017. The approach included deposition-associated sediment particles collected from sediment traps placed at each of 4 locations during the 2015 to 2016 wet seasons. The bioassays demonstrated wet season toxicity, especially closest to the creek mouth, and greater mortality associated with particles deposited in the wet season compared with dry season samples. Grain size analysis of sediment trap material indicated coarser sediment at the mouth of the creek and finer sediment in the outer depositional areas. Contaminant concentrations of metals (Cd, Cu, Hg, Ni, Pb, and Zn) and organic compounds (polycyclic aromatic hydrocarbons [PAHs], polychlorinated biphenyls [PCBs], and pesticides) were quantified to assess possible causes of toxicity. Contaminant concentrations were determined in the top 5 cm of sediment and porewater (using passive samplers). Whereas metals, PAHs, and PCBs were rarely detected at sufficient concentrations to elicit a response, pyrethroid pesticides were highly correlated with amphipod toxicity. Summing individual pyrethroid constituents using a toxic unit approach suggested that toxicity to E. estuarius could be associated with pyrethroids. This unique test design allowed delineation of spatial and temporal differences in toxicity, suggesting that storm water discharge from Paleta Creek may be the source of seasonal toxicity. Environ Toxicol Chem 2019;39:229-239. © 2019 SETAC.


Assuntos
Anfípodes/efeitos dos fármacos , Baías/química , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Estações do Ano , Poluentes Químicos da Água/toxicidade , Animais , California , Testes de Toxicidade , Poluentes Químicos da Água/análise
8.
Environ Sci Technol ; 53(9): 4860-4868, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30920807

RESUMO

We report freely dissolved concentrations ( Cfree) of PAHs in soils amended with 2.5% biochar and activated carbon (AC) during a long-term (18-months) field experiment. The study evaluates also the impact of different plants (clover, grass, willow) on Cfree PAHs. The cumulative effect of treatments on nitrogen and available forms of phosphorus, potassium, and magnesium is also assessed. The direct addition of biochar to soil did not cause any immediate reduction of the sum of 16 Cfree PAHs, while AC resulted in a slight reduction of 5- and 6 ring compounds. The efficiency of binding of Cfree PAHs by biochar and AC increased with time. For biochar, the maximum reduction of 4-6-ring PAHs (18-67%) was achieved within 6 months. For 2- and 3-ring PAHs, a gradual decrease of Cfree was observed which reached 60-66% at 18 months. AC proved to be better in reducing Cfree PAHs than biochar, though for 2- and 3-ring PAHs, the differences in AC and biochar performances were smaller than those for 4-6-ring PAHs. After 18 months, a significantly lower content of Cfree PAHs was observed in the soil with plants compared to the unplanted soil. Except for potassium, AC or biochar did not negatively impact nutrient availability.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Carbono , Carvão Vegetal , Poluição Ambiental , Solo
9.
Environ Sci Technol ; 52(6): 3574-3582, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29488382

RESUMO

This work presents the results of an international interlaboratory comparison on ex situ passive sampling in sediments. The main objectives were to map the state of the science in passively sampling sediments, identify sources of variability, provide recommendations and practical guidance for standardized passive sampling, and advance the use of passive sampling in regulatory decision making by increasing confidence in the use of the technique. The study was performed by a consortium of 11 laboratories and included experiments with 14 passive sampling formats on 3 sediments for 25 target chemicals (PAHs and PCBs). The resulting overall interlaboratory variability was large (a factor of ∼10), but standardization of methods halved this variability. The remaining variability was primarily due to factors not related to passive sampling itself, i.e., sediment heterogeneity and analytical chemistry. Excluding the latter source of variability, by performing all analyses in one laboratory, showed that passive sampling results can have a high precision and a very low intermethod variability (

Assuntos
Sedimentos Geológicos , Poluentes Químicos da Água , Monitoramento Ambiental , Compostos Orgânicos , Medição de Risco
10.
Integr Environ Assess Manag ; 11(2): 221-34, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25641867

RESUMO

Contaminated sediments can pose serious threats to human health and the environment by acting as a source of toxic chemicals. The amendment of contaminated sediments with strong sorbents like activated C (AC) is a rapidly developing strategy to manage contaminated sediments. To date, a great deal of attention has been paid to the technical and ecological features and implications of sediment remediation with AC, although science in this field still is rapidly evolving. This article aims to provide an update on the recent literature on these features, and provides a comparison of sediment remediation with AC to other sediment management options, emphasizing their full-scale application. First, a qualitative overview of advantages of current alternatives to remediate contaminated sediments is presented. Subsequently, AC treatment technology is critically reviewed, including current understanding of the effectiveness and ecological safety for the use of AC in natural systems. Finally, this information is used to provide a novel framework for supporting decisions concerning sediment remediation and beneficial reuse.


Assuntos
Carvão Vegetal/química , Recuperação e Remediação Ambiental , Sedimentos Geológicos/química
11.
Water Res ; 67: 96-104, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25262554

RESUMO

Addition of activated carbons (AC) to polluted sediments and soils is an attractive remediation technique aiming at reducing pore water concentrations of hydrophobic organic contaminants (HOCs). In this study, we present (pseudo-)equilibrium as well as kinetic parameters for sorption of a series of PAHs and PCBs to powdered and granular activated carbons (AC) after three different sediment treatments: sediment mixed with powdered AC (PAC), sediment mixed with granular AC (GAC), and addition of GAC followed by 2 d mixing and subsequent removal ('sediment stripping'). Remediation efficiency was assessed by quantifying fluxes of PAHs towards SPME passive samplers inserted in the sediment top layer, which showed that the efficiency decreased in the order of PAC > GAC stripping > GAC addition. Sorption was very strong to PAC, with Log KAC (L/kg) values up to 10.5. Log KAC values for GAC ranged from 6.3-7.1 and 4.8-6.2 for PAHs and PCBs, respectively. Log KAC values for GAC in the stripped sediment were 7.4-8.6 and 5.8-7.7 for PAH and PCB. Apparent first order adsorption rate constants for GAC (kGAC) in the stripping scenario were calculated with a first-order kinetic model and ranged from 1.6 × 10(-2) (PHE) to 1.7 × 10(-5) d(-1) (InP). Sorption affinity parameters did not change within 9 months post treatment, confirming the longer term effectiveness of AC in field applications for PAC and GAC.


Assuntos
Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Sedimentos Geológicos/química , Modelos Químicos , Hidrocarbonetos Policíclicos Aromáticos/química , Poluentes do Solo/química , Adsorção , Cinética
12.
Otolaryngol Pol ; 61(4): 623-5, 2007.
Artigo em Polonês | MEDLINE | ID: mdl-18260265

RESUMO

We describe children with orbital complications of acute sinusitis and analyse symptoms, diagnostic procedure and treatment options. We used X-ray and/or CT of paranasal sinuses to make diagnosis. The most frequent presenting orbital and occular symptoms are preseptal cellulitis and orbital cellulitis. Management of these children included intravenous antibiotic and we made maxillary sinus puncture with drainage. Proper recognition and treatment lead to total recovery.


Assuntos
Celulite Orbitária/diagnóstico por imagem , Celulite Orbitária/etiologia , Seios Paranasais/diagnóstico por imagem , Sinusite/complicações , Sinusite/diagnóstico por imagem , Doença Aguda , Feminino , Humanos , Masculino , Seio Maxilar/diagnóstico por imagem , Celulite Orbitária/terapia , Punções , Sinusite/terapia , Tomografia Computadorizada por Raios X
13.
Otolaryngol Pol ; 60(2): 181-5, 2006.
Artigo em Polonês | MEDLINE | ID: mdl-16903334

RESUMO

INTRODUCTION: Otitis media with effusion is a common problem in childhood. The tympanostomy tubes is a standard treatment of persistent otitis media with effusion in children which improves hearing level. However some pathological changes of the tympanic membrane and middle ear few years after treatment are observed. The aim of the study was prevalence of middle ear sequelaes in children with persistent otitis media with effusion treated by tympanostomy tubes 4-10 years after treatment. MATERIAL AND METHODS: The group of 61 patients aged between 1-13 with otitis media with effusion treated by tympanostomy tubes in Department of Otolaryngology Childrenís Hospital in Warsaw between 1994-2001 were controlled. 113 ears treated with tympanostomy tubes were examined 4-10 years after treatment. At the examination otomicroscope, pure-tone audiometry and tympanometry were used. RESULTS: Out of the 113 ears after ventilation tubes insertion as a method of otitis media with effusion treatment in 83 (73%) developed one or more middle ear sequelaes. Myringosclerosis in 47 ears (41,59%), segmental atrophy in 19 ears (16,81%), atrophy in 14 ears (12,38%), disfunction of Eustachian tube in 8 ears (7,07%), otitis media with effusion in 7 ears (6,19%), perforation of tympanic membrane in 6 ears (5,3%), chronic otitis media in 2 ears (1,76%), retraction pocket in 2 ears (1,76%) and tympanostomy tube in the middle ear cavity in 1 ear (0,88%) were found. No cases of cholesteatoma were found. In 22 ears (19,46%) the conductive hearing loss was greater than 20 dB. In 4 ears (3,5%) mixed hearing loss and in 3 ears (2,6%) receptable hearing loss was diagnosed. Tympanogram type A was in 86 ears (76,1%), tympanogram type B was in 11 ears (9,7%) and tympanogram type C was in 12 ears (12,6%). CONCLUSIONS: In children with otitis media with effusion treated with tympanostomy tubes the amount of sequelaes increased with time. In children with otitis media with effusion who started treatment with tympanostomy tubes in age to 4 years old the amount of sequelaes is less. The follow-up is recommended up to 8 years after the treatment.


Assuntos
Ventilação da Orelha Média , Otite Média com Derrame/cirurgia , Membrana Timpânica/cirurgia , Testes de Impedância Acústica , Limiar Auditivo , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Otite Média com Derrame/patologia , Polônia , Recidiva , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Membrana Timpânica/patologia
14.
Otolaryngol Pol ; 59(1): 71-6, 2005.
Artigo em Polonês | MEDLINE | ID: mdl-15915922

RESUMO

Hypertophy of pharyngeal tonsil and palatine tonsils is the most common cause of nasal obstruction in children. When the obstruction of the nasopharynx causes recurrent infections of upper respiratory tract, chronic otitis media secretoria or sleep apnoea, then adenoidectomy with or without tonsillectomy is indicated. The purpose of the study was analysis of postoperative hemorrhage after adenoidectomy with or without tonsillectomy. The influent of frequent infections of upper respiratory tract, disorders of blood clotting, chronic diseases, seasons of the year, operation time and general anesthesia on postoperative hemorrhage was estimated. A group of 1184 children after adenoidectomy with or without tonsillectomy was studied. Postoperative hemorrhage occurred in 59 children (4.98%). Early bleeding was frequently occurred after adenotonsillectomy and late bleeding after adenoidectomy. There was relationship between the time of general anesthesia and incidences of postoperative bleeding. Food or inhalation allergy, recurrent infections of upper respiratory tract and male sex are risk factors of postoperative hemorrhage after adenoidectomy with or without tonsillectomy.


Assuntos
Adenoidectomia/efeitos adversos , Hemorragia Pós-Operatória/epidemiologia , Hemorragia Pós-Operatória/etiologia , Tonsilectomia/efeitos adversos , Adenoidectomia/estatística & dados numéricos , Adolescente , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Hipertrofia/etiologia , Hipertrofia/cirurgia , Masculino , Polônia/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Tonsilectomia/estatística & dados numéricos
15.
Otolaryngol Pol ; 58(6): 1169-72, 2004.
Artigo em Polonês | MEDLINE | ID: mdl-15732843

RESUMO

Pott's puffy tumor is an infrequent entity characterized by subperiosteal abscess associated with frontal bone osteomyelitis. It is usually seen as a complication of frontal sinusitis. Although cases, in patients of all ages have been reported, teenagers are the most frequently affected. Despite modern methods of diagnosis and treatment, 9 new cases in children, have been published in the last 7 years. This paper describes the case of 13-year-old boy with subperiosteal abscess resulting from exacerbation of chronic frontal sinusitis. Complete resolution occurred with an intensive antibiotic regime and drainage of frontal sinus and subperiosteal abscess.


Assuntos
Sinusite Frontal/diagnóstico por imagem , Tuberculose da Coluna Vertebral/diagnóstico por imagem , Adolescente , Anti-Inflamatórios/uso terapêutico , Sinusite Frontal/complicações , Sinusite Frontal/tratamento farmacológico , Humanos , Masculino , Tomografia Computadorizada por Raios X , Tuberculose da Coluna Vertebral/complicações , Tuberculose da Coluna Vertebral/tratamento farmacológico
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