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1.
J Oncol Pharm Pract ; 25(3): 674-688, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30200843

RESUMO

PURPOSE: To create a set of consensus-based and evidence-informed recommendations to provide guidance around the safe dispensing and handling of oral anti-cancer drugs in low-volume settings unique to the community pharmacy setting. METHODS: A review of published and grey literature (published in non-commercial domains such as national organizations and associations) documents and nine key informant interviews were conducted and a modified Delphi approach was taken to achieve consensus. The final list of 47 candidate recommendations was reviewed by a task force and validated by multi-disciplinary stakeholders. A draft of the statements was circulated broadly within the community pharmacy community in an effort to assess relevance and implementation feasibility. RESULTS: The final report included 44 recommendations that addressed 11 key areas germane to the safe handling of oral anti-cancer drugs in community pharmacies. Mean agreement increased from 70% to 95%. Early feedback from community pharmacy leaders during the external review suggests that many of the proposed recommendations can be feasibly implemented within a reasonable timeframe when released with appropriate education and resource materials. CONCLUSIONS: A modified-Delphi approach supplemented by key informant interviews and a comprehensive external review resulted in a set of evidence-informed, community-driven recommendations for community pharmacies. The recommendations address a gap in existing literature to improve understanding of the risks associated with handling and dispensing oral anti-cancer drugs for both community pharmacy staff and management and offer mitigating strategies to reduce those risks. Incorporating feasibility assessment actions early (through the key informant interviews) and late (through the external review) ensures recommendations are grounded in practicality and support broad and early knowledge translation strategies.


Assuntos
Antineoplásicos , Serviços Comunitários de Farmácia/normas , Farmácias , Canadá , Consenso , Humanos
3.
Environ Toxicol Chem ; 36(11): 2981-2990, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28519901

RESUMO

We investigated individual toxicities of the nitrogen-based energetic materials (EMs) 2,4-dinitrotoluene (2,4-DNT); 2-amino-4,6-dinitrotoluene (2-ADNT); 4-amino-2,6-dinitrotoluene (4-ADNT); and nitroglycerin (NG) on microbial activity in Sassafras sandy loam (SSL) soil, which has physicochemical characteristics that support very high qualitative relative bioavailability for organic chemicals. Batches of SSL soil for basal respiration (BR) and substrate-induced respiration (SIR) assays were separately amended with individual EMs or acetone carrier control. Total microbial biomass carbon (biomass C) was determined from CO2 production increases after addition of 2500 mg/kg of glucose-water slurry to the soil. Exposure concentrations of each EM in soil were determined using US Environmental Protection Agency method 8330A. Basal respiration was the most sensitive endpoint for assessing the effects of nitroaromatic EMs on microbial activity in SSL, whereas SIR and biomass C were more sensitive endpoints for assessing the effects of NG in soil. The orders of toxicity (from greatest to least) were 4-ADNT > 2,4-DNT = 2-ADNT > NG for BR; but for SIR and biomass C, the order of toxicity was NG > 2,4-DNT > 2-ADNT = 4-ADNT. No inhibition of SIR was found up to and including the greatest concentration of each ADNT tested in SSL. These ecotoxicological data will be helpful in identifying concentrations of contaminant EMs in soil that present acceptable ecological risks for biologically mediated processes in soil. Environ Toxicol Chem 2017;36:2981-2990. Published 2017 Wiley Periodicals Inc. on behalf of SETAC.This article is a US government work and, as such, is in the public domain in the United States of America.


Assuntos
Bactérias/efeitos dos fármacos , Compostos de Nitrogênio/toxicidade , Microbiologia do Solo , Biomassa , Respiração Celular/efeitos dos fármacos , Sassafras/efeitos dos fármacos , Solo/química , Poluentes do Solo/toxicidade , Testes de Toxicidade
4.
J Hazard Mater ; 262: 143-50, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24021166

RESUMO

The high explosive nitroaromatic 2,4-dinitroanisole (DNAN) is less shock sensitive than 2,4,6-trinitrotoluene (TNT), and is proposed as a TNT replacement for melt-cast formulations. Before using DNAN in munitions and potentially leading to environmental impact, the present study examines the ecotoxicity of DNAN using selected organisms. In water, DNAN decreased green algae Pseudokirchneriella subcapitata growth (EC50 = 4.0mg/L), and bacteria Vibrio fischeri bioluminescence (Microtox, EC50 = 60.3mg/L). In soil, DNAN decreased perennial ryegrass Lolium perenne growth (EC50 =7 mg/kg), and is lethal to earthworms Eisenia andrei (LC50 = 47 mg/kg). At sub-lethal concentrations, DNAN caused an avoidance response (EC50 = 31 mg/kg) by earthworms. The presence of DNAN and 2-amino-4-nitroanisole in earthworms and plants suggested a role of these compounds in DNAN toxicity. Toxicity of DNAN was compared to TNT, tested under the same experimental conditions. These analyses showed that DNAN was equally, or even less deleterious to organism health than TNT, depending on the species and toxicity test. The present studies provide baseline toxicity data to increase the understanding of the environmental impact of DNAN, and assist science-based decision makers for improved management of potential DNAN contaminated sites.


Assuntos
Anisóis/toxicidade , Poluentes Ambientais/toxicidade , Substâncias Explosivas , Animais , Oligoquetos/efeitos dos fármacos , Trinitrotolueno/toxicidade
5.
Bioresour Technol ; 104: 775-82, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22154584

RESUMO

Presently lignin is used as fuel but recent interests in biomaterials encourage the use of this polymer as a renewable feedstock in manufacturing. The present study was undertaken to explore the potential applicability of microwaves to isolate lignin from agricultural residues. A central composite design (CCD) was used to optimize the processing conditions for the microwave (MW)-assisted extraction of lignin from triticale straw. Maximal lignin yield (91%) was found when using 92% EtOH, 0.64 N H(2)SO(4), and 148 °C. The yield and chemical structure of MW-extracted lignin were compared to those of lignin extracted with conventional heating. Under similar conditions, MW irradiation led to higher lignin yields, lignins of lower sugar content, and lignins of smaller molecular weights. Except for these differences the lignins resulting from both types of heating exhibited comparable chemical structures. The present findings should provide a clean source of lignin for potential testing in manufacturing of biomaterials.


Assuntos
Grão Comestível/química , Grão Comestível/efeitos da radiação , Lignina/isolamento & purificação , Lignina/efeitos da radiação , Modelos Químicos , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/efeitos da radiação , Simulação por Computador , Relação Dose-Resposta à Radiação , Lignina/química , Micro-Ondas , Doses de Radiação
6.
Sci Total Environ ; 409(24): 5284-91, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21975007

RESUMO

Nitroglycerin (NG) is widely used for the production of explosives and solid propellants, and is a soil contaminant of concern at some military training ranges. NG phytotoxicity data reported in the literature cannot be applied directly to development of ecotoxicological benchmarks for plant exposures in soil because they were determined in studies using hydroponic media, cell cultures, and transgenic plants. Toxicities of NG in the present studies were evaluated for alfalfa (Medicago sativa), barnyard grass (Echinochloa crusgalli), and ryegrass (Lolium perenne) exposed to NG in Sassafras sandy loam soil. Uptake and degradation of NG were also evaluated in ryegrass. The median effective concentration values for shoot growth ranged from 40 to 231 mg kg(-1) in studies with NG freshly amended in soil, and from 23 to 185 mg kg(-1) in studies with NG weathered-and-aged in soil. Weathering-and-aging NG in soil did not significantly affect the toxicity based on 95% confidence intervals for either seedling emergence or plant growth endpoints. Uptake studies revealed that NG was not accumulated in ryegrass but was transformed into dinitroglycerin in the soil and roots, and was subsequently translocated into the ryegrass shoots. The highest bioconcentration factors for dinitroglycerin of 685 and 40 were determined for roots and shoots, respectively. Results of these studies will improve our understanding of toxicity and bioconcentration of NG in terrestrial plants and will contribute to ecological risk assessment of NG-contaminated sites.


Assuntos
Echinochloa/efeitos dos fármacos , Lolium/efeitos dos fármacos , Medicago sativa/efeitos dos fármacos , Nitroglicerina/toxicidade , Poluentes do Solo/toxicidade , Echinochloa/crescimento & desenvolvimento , Lolium/crescimento & desenvolvimento , Medicago sativa/crescimento & desenvolvimento , Nitroglicerina/farmacocinética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Dióxido de Silício , Solo , Poluentes do Solo/farmacocinética
7.
J Environ Monit ; 13(8): 2304-11, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21734991

RESUMO

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a widely used explosive that is present in soils at a number of military sites, including training and testing ranges. Because of its relatively weak adsorption to soil, RDX frequently migrates through the unsaturated zone and causes groundwater contamination. In the environment, RDX can transform to produce mono-, di-, and tri-nitroso derivatives (MNX, DNX, and TNX) and the ring cleavage products methylenedinitramine (MEDINA) and 4-nitro-2,4-diazabutanal (NDAB). The present study was undertaken to analyze RDX and its products in groundwater samples taken from various US military sites. The stability of some of the common transformation intermediates of RDX, including the nitroso derivatives, NDAB and MEDINA, under typical conditions in a groundwater aquifer is not well understood, and appropriate preservation methods for these compounds have not been established. Therefore, we studied the inherent stability of these compounds in deionized water and in groundwater, and evaluated various preservation techniques, including adjustment of pH, temperature, and salinity. NDAB and nitroso derivatives were stable under typical ambient environmental conditions, but MEDINA was highly unstable. The addition of sea salts (10% w/v) was found to stabilize MEDINA when the samples were stored at 4 °C. Using appropriate preservation techniques, we detected nitroso derivatives and NDAB, but no MEDINA, at some of the sites investigated. Stabilizing RDX intermediate products in field samples to allow detection is important because the presence of any of these chemicals can indicate past contamination by RDX and provide insight into the occurrence of in situ natural attenuation.


Assuntos
Monitoramento Ambiental , Substâncias Explosivas/análise , Solo/análise , Triazinas/análise , Poluentes Químicos da Água/análise , Água/análise , Estados Unidos
8.
Appl Microbiol Biotechnol ; 84(3): 535-44, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19455327

RESUMO

The transformation of explosives, including hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), by xenobiotic reductases XenA and XenB (and the bacterial strains harboring these enzymes) under both aerobic and anaerobic conditions was assessed. Under anaerobic conditions, Pseudomonas fluorescens I-C (XenB) degraded RDX faster than Pseudomonas putida II-B (XenA), and transformation occurred when the cells were supplied with sources of both carbon (succinate) and nitrogen (NH4+), but not when only carbon was supplied. Transformation was always faster under anaerobic conditions compared to aerobic conditions, with both enzymes exhibiting a O2 concentration-dependent inhibition of RDX transformation. The primary degradation pathway for RDX was conversion to methylenedinitramine and then to formaldehyde, but a minor pathway that produced 4-nitro-2,4-diazabutanal (NDAB) also appeared to be active during transformation by whole cells of P. putida II-B and purified XenA. Both XenA and XenB also degraded the related nitramine explosives octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane. Purified XenB was found to have a broader substrate range than XenA, degrading more of the explosive compounds examined in this study. The results show that these two xenobiotic reductases (and their respective bacterial strains) have the capacity to transform RDX as well as a wide variety of explosive compounds, especially under low oxygen concentrations.


Assuntos
Proteínas de Bactérias/metabolismo , Substâncias Explosivas/metabolismo , Flavoproteínas/metabolismo , Oxirredutases/metabolismo , Pseudomonas fluorescens/enzimologia , Pseudomonas putida/enzimologia , Triazinas/metabolismo , Xenobióticos/metabolismo , Aerobiose , Anaerobiose , Compostos Aza/metabolismo , Azocinas/metabolismo , Proteínas de Bactérias/genética , Biodegradação Ambiental , Biotecnologia/métodos , Flavoproteínas/genética , Compostos Heterocíclicos/metabolismo , Oxirredutases/genética , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/crescimento & desenvolvimento , Pseudomonas fluorescens/metabolismo , Pseudomonas putida/genética , Pseudomonas putida/crescimento & desenvolvimento , Pseudomonas putida/metabolismo
9.
Tumori ; 94(2): 154-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18564600

RESUMO

All European countries are facing common challenges for delivering appropriate, evidence-based care to patients with cancer. Despite tangible improvements in diagnosis and treatment, marked differences in cancer survival exist throughout Europe. The reliable translation of new research evidence into consistent patient-oriented strategies is a key endeavour to overcome inequalities in healthcare. Clinical-practice guidelines are important tools for improving quality of care by informing professionals and patients about the most appropriate clinical practice. Guideline programmes in different countries use similar strategies to achieve similar goals. This results in unnecessary duplication of effort and inefficient use of resources. While different initiatives at the international level have attempted to improve the quality of guidelines, less investment has been made to overcome existing fragmentation and duplication of effort in cancer guideline development and research. To provide added value to existing initiatives and foster equitable access to evidence-based cancer care in Europe, CoCanCPG will establish cooperation between cancer guideline programmes. CoCanCPG is an ERA-Net coordinated by the French National Cancer Institute with 17 partners from 11 countries. The CoCanCPG partners will achieve their goal through an ambitious, stepwise approach with a long-term perspective, involving: 1. implementing a common framework for sharing knowledge and skills; 2. developing shared activities for guideline development; 3. assembling a critical mass for pertinent research into guideline methods; 4. implementing an appropriate framework for cooperation. Successful development of joint activities involves learning how to adopt common quality standards and how to share responsibilities, while taking into account the cultural and organisational diversity of the participating organisations. Languages barriers and different organisational settings add a level of complexity to setting up transnational collaboration. Through its activities, CoCanCPG will make an important contribution towards better access to evidence-based cancer practices and thus contribute to reducing inequalities and improving care for patients with cancer across Europe.


Assuntos
Medicina Baseada em Evidências , Disseminação de Informação , Cooperação Internacional , Neoplasias/terapia , Guias de Prática Clínica como Assunto , Qualidade da Assistência à Saúde , Benchmarking , Comunicação , Diversidade Cultural , Europa (Continente) , França , Disparidades em Assistência à Saúde , Humanos , Idioma
10.
J Environ Qual ; 37(3): 858-64, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18453407

RESUMO

Sinking of military ships, dumping of munitions during the two World Wars, and military training have resulted in the undersea deposition of numerous unexploded ordnances (UXOs). Leaching of energetic compounds such as hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) from these UXOs may cause adverse ecological effects so that the long-term fate of these chemicals in the sea should be known. The present study assesses the contribution of alkaline hydrolysis into the natural attenuation of RDX and HMX in coastal waters. Alkaline hydrolysis rates were shown to be unaffected by the presence of sodium chloride, the most common component in marine waters. Kinetic parameters (E(a), ln A, k(2)) quantified for the alkaline hydrolysis of RDX and HMX in deionized water (30-50 degrees C, pH 10-12) agreed relatively well with abiotic degradation rates determined in sterilized natural coastal waters (50 and 60 degrees C, variable salinity) even if the latter were generally slightly faster than the former. Furthermore, similar products (HCHO, NO(2)(-), O(2)NNHCH(2)NHCHO) were obtained on alkaline hydrolysis in deionized water and abiotic degradation in coastal waters. These two findings suggested that degradation of nitramines in sterilized natural coastal waters, away from light, was mainly governed by alkaline hydrolysis. Kinetic calculations using the present parameters showed that alkaline hydrolysis of RDX and HMX in marine waters at 10 degrees C would respectively take 112 +/- 10 and 2408 +/- 217 yr to be completed (99.0%). We concluded that under natural conditions hydrolysis should not contribute significantly to the natural attenuation of HMX in coastal waters whereas it could play an active role in the natural attenuation of RDX.


Assuntos
Azocinas/química , Triazinas/química , Poluentes Químicos da Água/química , Cinética , Água do Mar
11.
Int J Qual Health Care ; 18(3): 167-76, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16766601

RESUMO

PURPOSE: The development and updating of high-quality clinical practice guidelines require substantial resources. Many guideline programmes throughout the world are using similar strategies to achieve similar goals, resulting in many guidelines on the same topic. One method of using resources more efficiently and avoiding unnecessary duplication of effort would be to adapt existing guidelines. The aim was to review the literature on adaptation of guidelines and to propose a systematic approach for adaptation of guidelines. DATA SOURCES: We selected and reviewed reports describing the methods and results of adaptation of guidelines from those found by searching Medline, Internet, and reference lists of relevant papers. On the basis of this review and our experience in guideline development, we proposed a conceptual framework and procedure for adaptation of guidelines. RESULTS: Adaptation of guidelines is performed either as an alternative to de novo guideline development or to improve guideline implementation through local tailoring of an international or national guideline. However, no validated process for the adaptation of guidelines produced in one cultural and organizational setting for use in another (i.e. trans-contextual adaptation) was found in the literature. The proposed procedure is a stepwise approach to trans-contextual adaptation, including searching for existing guidelines, quality appraisal, detailed analysis of the coherence between the evidence and the recommendations, and adaptation of the recommendations to the target context of use, taking into account the organization of the health care system and cultural context. CONCLUSIONS: Trans-contextual adaptation of guidelines is increasingly being considered as an alternative to de novo guideline development. The proposed approach should be validated and evaluated to determine if it can reduce duplication of effort and inefficient use of resources, although guaranteeing a high-quality product, compared with de novo development.


Assuntos
Difusão de Inovações , Guias de Prática Clínica como Assunto/normas , Europa (Continente)
12.
Chemosphere ; 62(4): 545-58, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16112172

RESUMO

The toxicities of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitrobenzene (TNB), 2,4-dinitrotoluene (2,4-DNT), and 2,6-dinitrotoluene (2,6-DNT) to terrestrial plants alfalfa (Medicago sativa L.), Japanese millet (Echinochloa crusgalli L.), and perennial ryegrass (Lolium perenne L.) were determined in Sassafras sandy loam soil using seedling emergence, fresh shoot, and dry mass measurement endpoints. A 13-week weathering and aging of energetic materials in soils, which included wetting and drying cycles, and exposure to sunlight of individual soil treatments, was incorporated into the study design to better reflect the soil exposure conditions in the field than toxicity determinations in freshly amended soils. Definitive toxicity tests showed that dinitrotoluenes were more phytotoxic for all plant species in freshly amended treatments based on EC20 values for dry shoot ranging from 3 to 24mgkg(-1) compared with values for TNB or TNT ranging from 43 to 62mgkg(-1). Weathering and aging of energetic materials (EMs) in soil significantly decreased the toxicity of TNT, TNB or 2,6-DNT to Japanese millet or ryegrass based on seedling emergence, but significantly increased the toxicity of all four EMs to all three plant species based on shoot growth. Exposure of the three plant species to relatively low concentrations of the four compounds initially stimulated plant growth before the onset of inhibition at greater concentrations (hormesis).


Assuntos
Derivados de Benzeno/toxicidade , Echinochloa/efeitos dos fármacos , Lolium/efeitos dos fármacos , Medicago sativa/efeitos dos fármacos , Poluentes do Solo/toxicidade , Derivados de Benzeno/análise , Echinochloa/crescimento & desenvolvimento , Lolium/crescimento & desenvolvimento , Medicago sativa/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Dióxido de Silício , Solo , Poluentes do Solo/análise , Fatores de Tempo , Tempo (Meteorologia)
13.
Int J Syst Evol Microbiol ; 55(Pt 4): 1511-1520, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16014474

RESUMO

Previously, a psychrophilic rod-shaped marine bacterium (strain HAW-EB3(T)) isolated from Halifax Harbour sediment was noted for its ability to degrade hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). In the present study phenotypic, chemotaxonomic and genotypic characterization showed that strain HAW-EB3(T) represents a novel species of Shewanella. Strain HAW-EB3(T) contained lysine decarboxylase, which is absent in other known Shewanella species, and distinguished itself from most other species of Shewanella by the presence of arginine dehydrolase, ornithine decarboxylase and chitinase, and by its ability to oxidize and ferment N-acetyl-d-glucosamine. Strain HAW-EB3(T) grew on several carbon sources (N-acetyl-d-glucosamine, Tween 40, Tween 80, acetate, succinate, butyrate and serine) and showed distinctive fatty acid and quinone compositions. Both phenotypic and 16S rRNA gene phylogenetic cluster analyses demonstrated that HAW-EB3(T) belongs to the Na(+)-requiring group of Shewanella species. The HAW-EB3(T) 16S rRNA gene sequence displayed < or =97.4 % similarity to all known Shewanella species and was most similar to those of two bioluminescent species, Shewanella hanedai and Shewanella woodyi. However, gyrB of strain HAW-EB3(T) was significantly different from those of other Shewanella species, with similarities less than 85 %. DNA-DNA hybridization showed that its genomic DNA was less than 25 % related to that of S. hanedai or S. woodyi. Therefore we propose Shewanella sediminis sp. nov., with HAW-EB3(T) (=NCIMB 14036(T)=DSM 17055(T)) as the type strain.


Assuntos
Sedimentos Geológicos/microbiologia , Água do Mar/microbiologia , Shewanella/classificação , Sódio/metabolismo , Triazinas/metabolismo , Técnicas de Tipagem Bacteriana , Biodegradação Ambiental , DNA Bacteriano , DNA Ribossômico , Genes de RNAr , Genótipo , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fenótipo , RNA Ribossômico 16S , Análise de Sequência de DNA , Shewanella/química , Shewanella/genética , Shewanella/fisiologia
14.
J Chromatogr A ; 1072(1): 73-82, 2005 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-15881461

RESUMO

An Agilent 3DCE capillary electrophoresis system using sulfobutylether-beta-cyclodextrin (SB-beta-CD)-ammonium acetate separation buffer pH 6.9 was coupled to a Bruker Esquire 3000+ quadrupole ion trap mass detector via a commercially available electrospray ionization interface with acetonitrile sheath flow. The CE-MS system was applied in negative ionization mode for the resolution and detection of nitroaromatic and polar cyclic or caged nitramine energetic materials including TNT [2,4,6-trinitrotoluene, formula mass (FW) 227.13], TNB (1,3,5-trinitrobenzene, FW 213.12), RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine, FW 222.26) HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, FW 296.16), and CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, FW 438.19). The CE-MS system conformed to the high-performance liquid chromatography with ultraviolet absorbance detection (HPLC-UV) and HPLC-MS reference methods for the identification of energetic contaminants and their degradation products in soil and marine sediment samples.


Assuntos
Eletroforese Capilar/métodos , Poluentes Ambientais/análise , Sedimentos Geológicos/química , Nitrocompostos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Compostos Aza/análise , Azocinas/análise , Compostos Heterocíclicos/análise , Compostos Heterocíclicos com 1 Anel/análise , Triazinas/análise , Trinitrobenzenos/análise , Trinitrotolueno/análise , beta-Ciclodextrinas
15.
Environ Sci Technol ; 39(24): 9725-31, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16475359

RESUMO

RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) are cyclic nitramines ((CH2NNO2)n; n = 3 or 4, respectively) widely used as energetic chemicals. Their extensive use led to wide environmental contamination. In contrast to RDX, HMX tends to accumulate in soils due to its unique recalcitrance. In the present study, we investigated the potential of zerovalent iron (ZVI) to transform HMX under anoxic conditions. HMX underwent a rapid transformation when added in well-mixed anoxic ZVI-H2O batch systems to ultimately produce formaldehyde (HCHO), ammonium (NH4+), hydrazine (NH2NH2), and nitrous oxide (N2O). Time course experiments showed that the mechanism of HMX transformation occurred through at least two initial reactions. One reaction involved the sequential reduction of N-NO2 groups to the five nitroso products (1NO-HMX, cis-2NO-HMX, trans-2NO-HMX, 3NO-HMX, and 4NO-HMX). Another implied ring cleavage from either HMX or 1NO-HMX as demonstrated by the observation of methylenedinitramine (NH(NO2)CH2NH(NO2)) and another intermediate that was tentatively identified as (NH(NO2)CH2N(NO)CH2NH-(NO2)) or its isomer (NH(NO)CH2N(NO2)CH2NH(NO2)). This is the first study that demonstrates transformation of HMX by ZVI to significant amounts of NH2NH2 and HCHO. Both toxic products seemed to persist under reductive conditions, thereby suggesting that the ultimate fate of these chemicals, particularly hydrazine, should be understood prior to using zerovalent iron to remediate cyclic nitramines.


Assuntos
Azocinas/metabolismo , Compostos Heterocíclicos com 1 Anel/metabolismo , Ferro/química , Esgotos/microbiologia , Microbiologia do Solo , Poluentes do Solo/metabolismo , Anaerobiose , Compostos de Anilina/metabolismo , Azocinas/toxicidade , Formaldeído/metabolismo , Compostos Heterocíclicos com 1 Anel/toxicidade , Hidrazinas/metabolismo , Ferro/farmacologia , Isomerismo , Nitrobenzenos/metabolismo , Óxido Nitroso/metabolismo , Compostos de Amônio Quaternário/metabolismo , Poluentes do Solo/toxicidade , Fatores de Tempo
16.
Water Res ; 38(19): 4055-64, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15491653

RESUMO

Hexanitrohexaazaisowurtzitane (HNIW) or CL-20 is a caged structure polycyclic nitramine that may replace RDX and HMX as a common use energetic chemical. To provide insight into the environmental fate of CL-20 we photolyzed the chemical in a Rayonet photoreactor (254-350 nm) and with sunlight in aqueous solutions. Previously, we found that initial photodenitration of the monocyclic nitramine RDX leads to ring cleavage and decomposition. Presently, we found that photolysis of the rigid molecule CL-20 produced NO2-, NO3-, NH3, HCOOH, N2 and N2O. Using LC/MS (ES-) we detected several key intermediates carrying important information on the initial steps involved in the degradation of CL-20. The identities of the intermediates were confirmed using a uniformly ring labeled 15N-[CL-20]. When CL-20 was photolyzed in the presence of H2(18)O, D2O or 18O2 we obtained a product distribution suggesting that the energetic chemical degraded via at least two initial routes; one involved sequential homolysis of N-NO2 bond(s) and another involved photorearrangement prior to hydrolytic ring cleavage and decomposition in water.


Assuntos
Compostos Aza/química , Compostos Heterocíclicos/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Hidrólise , Fotoquímica
17.
J Chromatogr A ; 1048(2): 213-21, 2004 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-15481259

RESUMO

When explosives are present in natural aqueous media, their concentration is usually limited to trace levels. A preconcentration step able to remove matrix interferences and to enhance sensitivity is therefore necessary. In the present study, we evaluated solid-phase microextraction (SPME) technique for the recovery of nine explosives from aqueous samples using high-performance liquid chromatography with ultraviolet detection (HPLC-UV). Several parameters, including adsorption and desorption time, coating type, rate of stirring, salt addition, and pH, were optimized to obtain reproducible data with good accuracy. Carbowax coating was the only adsorbent found capable of adsorbing all explosives including nitramines. Method detection limits (MDL) were found to range from 1 to 10 microg/L, depending on the analyte. SPME/HPLC-UV coupling was then applied to the analysis of natural ocean and groundwater samples and compared to conventional solid-phase extraction (SPE/HPLC-UV). Excellent agreement was observed between both techniques, but with an analysis time around five times shorter, SPME/HPLC-UV was considered to be applicable for quantitative analysis of explosives.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Explosões , Espectrofotometria Ultravioleta/métodos , Poluentes Químicos da Água/análise , Água/análise , Adsorção , Calibragem , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Sais/química , Tempo
18.
FEMS Microbiol Lett ; 237(1): 65-72, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15268939

RESUMO

Several H2-producing fermentative anaerobic bacteria including Clostridium, Klebsiella and Fusobacteria degraded octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) (36 microM) to formaldehyde (HCHO) and nitrous oxide (N2O) with rates ranging from 5 to 190 nmol h(-1)g [dry weight] of cells(-1). Among these strains, C. bifermentans strain HAW-1 grew and transformed HMX rapidly with the detection of the two key intermediates the mononitroso product and methylenedinitramine. Its cellular extract alone did not seem to degrade HMX appreciably, but degraded much faster in the presence of H2, NADH or NADPH. The disappearance of HMX was concurrent with the release of nitrite without the formation of the nitroso derivative(s). Results suggest that two types of enzymes were involved in HMX metabolism: one for denitration and the second for reduction to the nitroso derivative(s).


Assuntos
Azocinas/metabolismo , Bactérias Anaeróbias/metabolismo , Clostridium/metabolismo , Compostos Heterocíclicos com 1 Anel/metabolismo , Anaerobiose , Biodegradação Ambiental , Fermentação , Formaldeído/metabolismo , Fusobactérias/metabolismo , Hidrogênio/metabolismo , Klebsiella/metabolismo , NAD/metabolismo , NADP/metabolismo , Nitritos/metabolismo , Óxido Nitroso/metabolismo , Oxirredução , Poluentes do Solo/metabolismo
19.
Ecotoxicol Environ Saf ; 58(3): 300-13, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15223256

RESUMO

Explosives are released into the environment at production and processing facilities, as well as through field use. These compounds may be toxic at relatively low concentrations to a number of ecological receptors. A toxicity assessment was carried out on soils from an explosive-contaminated site at a Canadian Forces Area Training Center. Toxicity studies on soil organisms using endpoints such as microbial processes (potential nitrification activity, dehydrogenase activity, substrate-induced respiration, basal respiration), plant seedling and growth (Lactuca sativa and Hordeum vulgare), and earthworm (Eisenia andrei) growth and reproduction were carried out. Results showed that 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane (HMX) was the principal polynitro-organic compound measured in soils. Soils from the contaminated site decreased microbial processes and earthworm reproduction; whereas plant growth was not significantly reduced. Toxicity to aquatic organisms and genotoxicity were also assessed on soil elutriates using Microtox (Vibrio fischeri), growth inhibition of algae (Selenastrum capricornutum), and SOS Chromotest (Escherichia coli). Results indicated that soil elutriates were generally not toxic to bacteria (Microtox) and algae. However, genotoxicity was found in a number of soil elutriate samples. Thus, the explosive-contaminated soils from the antitank firing range may represent a hazard for the soil organisms. Nevertheless, the global toxicity might have partially resulted from HMX as well as from other (not identified) contaminants such as heavy metals.


Assuntos
Ecologia , Armas de Fogo , Ciência Militar , Poluentes do Solo/toxicidade , Animais , Azocinas/análise , Canadá , Clorófitas/efeitos dos fármacos , Clorófitas/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Compostos Heterocíclicos com 1 Anel/análise , Concentração Inibidora 50 , Testes de Mutagenicidade , Nível de Efeito Adverso não Observado , Oligoquetos/efeitos dos fármacos , Oligoquetos/fisiologia , Desenvolvimento Vegetal , Plantas/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Medição de Risco , Solo/análise , Poluentes do Solo/análise , Vibrio/efeitos dos fármacos
20.
J Chromatogr A ; 1025(1): 125-32, 2004 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-14753679

RESUMO

CL-20 is a polycyclic energetic nitramine, which may soon replace the monocyclic nitramines RDX and HMX, because of its superior explosive performance. Therefore, to predict its environmental fate, analytical and physico-chemical data must be made available. An HPLC technique was thus developed to measure CL-20 in soil samples based on the US Environmental Protection Agency method 8330. We found that the soil water content and aging (21 days) had no effect on the recoveries (>92%) of CL-20, provided that the extracts were kept acidic (pH 3). The aqueous solubility of CL-20 was poor (3.6 mg l(-1) at 25 degrees C) and increased with temperature to reach 18.5 mg l(-1) at 60 degrees C. The octanol-water partition coefficient of CL-20 (log KOW = 1.92) was higher than that of RDX (log KOW = 0.90) and HMX (log KOW = 0.16), indicating its higher affinity to organic matter. Finally, CL-20 was found to decompose in non-acidified water upon contact with glass containers to give NO2- (2 equiv.), N2O (2 equiv.), and HCOO- (2 equiv.). The experimental findings suggest that CL-20 should be less persistent in the environment than RDX and HMX.


Assuntos
Compostos Aza/análise , Azocinas/análise , Monitoramento Ambiental/métodos , Compostos Heterocíclicos com 1 Anel/análise , Compostos Heterocíclicos/análise , Triazinas/análise
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