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1.
J Nepal Health Res Counc ; 20(1): 251-256, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35945885

RESUMO

BACKGROUND: The growing concern over pesticide use has been linked to self-harm and suicide especially in agricultural countries like Nepal.  Pesticides like organophosphorus and aluminum phosphide cause the majority of deaths. Although organophosphorus poisoning is common means for suicide, Aluminum phosphide poisoning is also encountered occasionally. Our case series aims to look after the intent of poisoning and the outcome of the patients following Aluminum phosphide poisoning. METHODS: This hospital record-based study includes Aluminum phosphide poisoning patients presenting to the emergency department of Scheer Memorial Adventist Hospital from first January 2017 to 31st December 2020. Data were analyzed using SPSS version-22. RESULTS:   Out of 25 total poisoning cases, most of them were female (60%) and married (56%).  The case fatality rate was 84% among which 20% cases were brought dead while 64% died in the hospital. All poisoning cases were suicidal in intent. CONCLUSIONS: Herein we report a case series on 25 Aluminum phosphide poisoning cases with high case fatality rate and all cases being suicidal in intent.


Assuntos
Praguicidas , Fosfinas , Compostos de Alumínio , Feminino , Humanos , Masculino , Nepal/epidemiologia , Fosfinas/análise
2.
J Chromatogr A ; 1637: 461833, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33373796

RESUMO

The reliable determination of arsine (AsH3) and phosphine (PH3) in hydrogen (H2), nitrogen (N2) and liquefied petroleum gas (LPG) is of great importance because of its drastic effects on the efficiency of catalysts, as well as the strict regulations associated with health, safety and environmental issues. It is challenging for an analyst to determine the parts per billion of AsH3 and PH3 in H2, N2, and LPG at low and high pressures without collection procedures using adsorption, desorption, and dissolution techniques. To overcome this analytical need an analytical methodology was developed, employing a variable pressure sampler (VPS) coupled to a gas chromatograph (GC) with mass spectrometry (MS) for the identification and quantification of traces of AsH3 and PH3. The instrumentation, tubing and accessories of the VPS were made of passivated steel to avoid losses from absorption of AsH3 and PH3 in the steel which would generate significant analytical problems. The VPS had a homogeneous heating block that prevented analyte losses from condensation. With the VPS, 24 AsH3 and PH3 standards were prepared between 0.005 and 0.1 mg kg-1 in balance of H2, N2 and LPG. The separation and quantification of the analytes was achieved with an improved GC with 4 valves and 5 columns in series that guaranteed the elimination of impurities. The proposed method was optimized in VPS and GC-MS and then validated showing highly accaptable linearity (r2 > 0.9999), detection limits (<0.0009 mg kg-1), limits of quantification (<0.003 mg kg-1), intra-day and inter-day precision and accuracy (<1.14% and ≤3.0% respectively), recovery for the standard addition (86-109%), P values> 0.05 for the test Student's t paired who evaluated the effect of the matrix on pressure and concentration. The speed of analysis was high (<5.2 min). The method was applied to real samples, showing values between 0.005 and 0.1 mg kg-1 and an effect on the efficiency of the Ziegler Natta catalyst between 5 and 56%.


Assuntos
Arsenicais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrogênio/química , Nitrogênio/química , Petróleo/análise , Fosfinas/análise , Humanos , Limite de Detecção , Reprodutibilidade dos Testes
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 235: 118280, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32248034

RESUMO

To clarify the interaction of phosphine copper(I) complex with DNA, our study reports the synthesis of a new phosphine copper(I) complex, along with a detailed analysis of the geometry characterization and its interaction with double-stranded DNA. The triclinic phase Cu(PPh3)2(L)(I) with a tetrahedral geometry was identified as the product of the reaction of copper(I) iodide with (E,E)-N,N'-1,2-Ethanediylbis[1-(3-pyridinyl)methanimine] ligand and triphenylphosphine by single-crystal X-ray analysis. Molecular interaction of the synthesized complex with the calf thymus deoxyribonucleic acid (ct-DNA) was investigated in the physiological buffer (pH 7.4) by multi-spectroscopic approaches associated with a competitive displacement towards Hoechst 33258 and methylene blue (MB) as groove and intercalator probes. The fluorescence and UV/Vis results detected the formation of a complex-DNA adduct in the ground-state with a binding affinity in order of 104 M-1, which is in keeping with both groove binders and intercalators. The thermodynamic parameters, ΔS0 = -200.31 ± 0.08 cal/mol·K and ΔH0 = -63.11 ± 0.24 kcal/mol, confirmed that the van der Waals interaction is the main driving force for the binding process. Moreover, the ionic strength and pH effect experiments demonstrated the electrostatic interactions between the complex and DNA is negligible. Analysis of the molecular docking simulation declared the flat (E,E)-N,N'-1,2-Ethanediylbis[1-(3-pyridinyl)methanimine] part of the complex was inserted between the sequential A…T/A…T base pairs, while the phosphine substituents were located in the groove, i.e. threading intercalation. Besides, the cytotoxicity of the complex against the MCF-7 human breast cancer cells was detected at IC50 = 10 µg/mL.


Assuntos
Cobre/análise , DNA/análise , Fosfinas/análise , Apoptose , Sítios de Ligação , DNA/química , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Concentração Inibidora 50 , Íons , Células MCF-7 , Modelos Moleculares , Simulação de Acoplamento Molecular , Concentração Osmolar , Espectrofotometria Ultravioleta , Eletricidade Estática , Termodinâmica , Raios X
4.
Rapid Commun Mass Spectrom ; 34(10): e8738, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31981253

RESUMO

RATIONALE: Determination of phosphine exposure from zinc or aluminum phosphide fumigants continues to be a routine analytical requirement in veterinary forensic toxicology. There is a need for a more reliable and specific method than simple gas chromatography/mass spectrometry (GC/MS) analysis of sample solvent extracts, as GC/MS of extracts on capillary columns used for general screens involves significant interference from air peaks. METHODS: GC/MS/MS headspace analysis of acid-generated phosphine gas enabled study of the feasibility of devising multiple reaction monitoring (MRM) approaches to the determination of phosphine with greater specificity. RESULTS: Collision-induced dissociation in GC/MS/MS showed that phosphine generated m/z 34 → 31, 32 and 33 ion transitions by sequential proton release as well as minor transitions m/z 34 → 47, 34 → 63 and 63 → 31.5 by intermolecular collisions and double charging. Study of the formation of these product ions enabled development of MRM settings for a highly useful headspace method for phosphine detection. CONCLUSIONS: The method was validated over a working range of 5-100 ppm of phosphide generating phosphine gas which enabled retention of regular screen capillary columns without necessitating separation from air components. The method should have adequate sensitivity and reliability for veterinary toxicology laboratories confronting specimens from animals poisoned by crop fumigants.


Assuntos
Praguicidas/análise , Fosfinas/análise , Espectrometria de Massas em Tandem/métodos , Compostos de Alumínio/análise , Animais , Toxicologia Forense/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limite de Detecção , Medicina Veterinária/métodos , Compostos de Zinco/análise
5.
Astrobiology ; 20(2): 235-268, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31755740

RESUMO

A long-term goal of exoplanet studies is the identification and detection of biosignature gases. Beyond the most discussed biosignature gas O2, only a handful of gases have been considered in detail. In this study, we evaluate phosphine (PH3). On Earth, PH3 is associated with anaerobic ecosystems, and as such, it is a potential biosignature gas in anoxic exoplanets. We simulate the atmospheres of habitable terrestrial planets with CO2- and H2-dominated atmospheres and find that PH3 can accumulate to detectable concentrations on planets with surface production fluxes of 1010 to 1014 cm-2 s-1 (corresponding to surface concentrations of 10s of ppb to 100s of ppm), depending on atmospheric composition and ultraviolet (UV) irradiation. While high, the surface flux values are comparable to the global terrestrial production rate of methane or CH4 (1011 cm-2 s-1) and below the maximum local terrestrial PH3 production rate (1014 cm-2 s-1). As with other gases, PH3 can more readily accumulate on low-UV planets, for example, planets orbiting quiet M dwarfs or with a photochemically generated UV shield. PH3 has three strong spectral features such that in any atmosphere scenario one of the three will be unique compared with other dominant spectroscopic molecules. Phosphine's weakness as a biosignature gas is its high reactivity, requiring high outgassing rates for detectability. We calculate that tens of hours of JWST (James Webb Space Telescope) time are required for a potential detection of PH3. Yet, because PH3 is spectrally active in the same wavelength regions as other atmospherically important molecules (such as H2O and CH4), searches for PH3 can be carried out at no additional observational cost to searches for other molecular species relevant to characterizing exoplanet habitability. Phosphine is a promising biosignature gas, as it has no known abiotic false positives on terrestrial planets from any source that could generate the high fluxes required for detection.


Assuntos
Atmosfera/química , Exobiologia/métodos , Meio Ambiente Extraterreno/química , Gases/análise , Fosfinas/análise , Atmosfera/análise , Biomarcadores/análise , Exobiologia/instrumentação , Análise Espectral/instrumentação , Análise Espectral/métodos , Telescópios
6.
J Anal Toxicol ; 42(5): 330-336, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29378027

RESUMO

Phosphine is an insecticide for the fumigation of grains, animal feed, and leaf-stored tobacco, and it was used as a rodenticide in bulk grain stores. Phosphine poisoning may occur after accidental inhalation of phosphine, sometimes leading to death. Analysis of phosphine and its metabolites in postmortem specimens from seven fatal cases was conducted in this study, as well as postmortem specimens collected from rabbits exposed to phosphine. The total phosphine in postmortem specimens was analyzed by headspace gas chromatography coupled with mass spectrometry. Diagnosis of aluminum phosphide poisoning was made after postmortem toxicological analysis and confirmed by police investigation. The deaths of the children occurred after inhalation of phosphine generated from aluminum phosphide contacting moisture in the air in all seven fatal cases. The concentration of total phosphine in the biological fluids and tissues of victims ranged from 0.2 to 4.7 µg/mL (µg/g). Animal experiments demonstrated that the phosphine generated from aluminum phosphide could rapidly cause death. The toxicological analysis of postmortem specimens provides useful information in diagnosis of aluminum phosphide poisoning in forensic science. As an important fumigation pesticide, aluminum phosphide deserves special attention, especially since there is no specific antidote and there is a high fatality rate.


Assuntos
Compostos de Alumínio/toxicidade , Exposição por Inalação/efeitos adversos , Inseticidas/toxicidade , Intoxicação por Organofosfatos/metabolismo , Fosfinas/análise , Fosfinas/toxicidade , Rodenticidas/toxicidade , Animais , Biotransformação , Cadáver , Criança , Pré-Escolar , Feminino , Fumigação/efeitos adversos , Humanos , Rim/química , Rim/patologia , Fígado/química , Fígado/patologia , Pulmão/química , Pulmão/patologia , Masculino , Intoxicação por Organofosfatos/diagnóstico , Intoxicação por Organofosfatos/mortalidade , Intoxicação por Organofosfatos/patologia , Fosfinas/sangue , Fosfinas/urina , Coelhos , Estudos Retrospectivos , Distribuição Tecidual , Toxicocinética
7.
Dalton Trans ; 47(3): 742-749, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29242864

RESUMO

A novel fluorescent receptor L was synthesized by Schiff base condensation of 1-pyrenemethylamine with the vitamin B6 cofactor pyridoxal. The receptor L is highly selective and sensitive towards Zn2+ ions among other tested metal ions. Upon interaction with Zn2+, the receptor L showed a distinct fluorescence enhancement at 485 nm due to the excimer formation leading to the fluorescent colour change from blue to bluish-green. Subsequently, when the in situ generated ZnL2 complex interacted with various anions and amino acids, the addition of H2PO4- and cysteine reinstated the fluorescence of the receptor L due to the demetalation of Zn2+ from the ZnL2 complex. Accordingly, the receptor L was developed for the highly selective, specific and sensitive detection of three important bioactive analytes, i.e., Zn2+, H2PO4- and cysteine with a detection limit down to 2.3 × 10-6 M, 2.18 × 10-7 M and 1.59 × 10-7 M, respectively. Additionally, the receptor L was applied to the detection of intracellular Zn2+ ions in live HeLa cells.


Assuntos
Técnicas de Química Analítica/instrumentação , Cisteína/análise , Fosfinas/análise , Piridoxal/química , Zinco/análise , Cisteína/química , Células HeLa , Humanos , Limite de Detecção , Modelos Moleculares , Conformação Molecular , Imagem Molecular , Fosfinas/química , Espectrometria de Fluorescência , Zinco/química
8.
Int J Legal Med ; 131(4): 1001-1007, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28243772

RESUMO

Aluminum phosphide (AlP) is an effective and cheap pesticide that is commonly used worldwide, but it is also a common cause of human poisoning and carries a high mortality rate. AlP reacts with moisture in air, water, and hydrochloric acid in the stomach to produce phosphine (PH3) gas. Two routes of exposure are ingestion of AlP and inhalation of phosphine generated by the action of moisture on AlP. Absorbed phosphine is rapidly metabolized into phosphite and hypophosphite. A method is described for the analysis of the phosphine metabolites in various biological matrices. The method involves reacting the sample with zinc and aqueous H2SO4 in a volatile organic analysis vial. The metabolites were transformed into phosphine gas and then analyzed by headspace gas chromatography coupled with mass spectrometry (HS-GC-MS). This method is capable of detecting quantities of PH3 as low as 0.2 µg/mL in a sample. After validation, the method was applied to animal experiments and a real case of human AlP intoxication. This approach has the advantage of detecting metabolites of PH3, in case the PH3 was converted, and can be considered a useful additional tool for the diagnosis of AlP poisoning in forensic science.


Assuntos
Compostos de Alumínio/análise , Compostos de Alumínio/intoxicação , Praguicidas/análise , Praguicidas/intoxicação , Fosfinas/análise , Fosfinas/intoxicação , Animais , Toxicologia Forense/métodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Limite de Detecção , Intoxicação/diagnóstico , Ratos
9.
Eur J Mass Spectrom (Chichester) ; 22(5): 275-287, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27882894

RESUMO

Tetrahedral [Cu(P)4][BF4]-type complexes (P = tertiary phosphine) are a class of monopositively charged compounds that have shown notable antitumor activity in both in vitro and in vivo tests. This biological property appears to be related to the peculiar physicochemical characteristics of these compounds. Although thermodynamically stable, they are labile at micromolar concentrations. Such a behavior allows the Cu(I) ion in [Cu(P)n]+ assemblies (n < 4) to interact with surrounding molecules, including the rich peptide/protein environment that metal complexes have to face in the physiological milieu on the way to tumor cells. The scope of this investigation was to study the interaction products that originate from the treatment in water/methanol mixtures of representative phosphino Cu(I) compounds with an excess of individual amino acids (AAs) selected on the basis of the donor atom likely involved in metal coordination (i.e. O-glycine, S-methionine and N-histidine). These interactions have been investigated in electrospray ionization mass spectrometry (ESI-MS), mainly in the positive ion mode [ESI(+)MS], and the interaction products have been characterized by sequential collisional experiments, performed by an ion trap instrument. Histidine and methionine, but not glycine, were able to mine Cu(I) from [Cu(P)n]+ assemblies through the formation of mixed [CuI(P)(AA)]+ and eventually [CuI(AA)2]+ adducts. The ability to substitute phosphine(s) by AAs and the strongest affinity for Cu(I) was proved by the study of the energetics of collisional-induced decomposition (CID) reactions [CuI(P)(AA)]+ → CuI(AA) + P]+. Among the investigated AAs, histidine displayed the strongest affinity for Cu(I). Transchelation of Cu(I) was similarly observed when [Cu(P)n]+ species were treated with the model tripeptide GlyGlyHis (GGH), the most investigated member of the amino terminal Cu(II) and Ni(II) (ATCUN) peptide family. GGH was able to form robust metal adducts not only with Cu(II) and the related divalent Zn(II) and Ni(II) ions, but also with monovalent ions, including Cu(I) and Ag(I). CID pathways of [CuI(GGH)]+ and [AgI(GGH)]+ were qualitatively superimposable and proceeded through losses of neutral fragments. Similar losses of neutral fragments were observed from [ZnII(GGH)] and [NiII(GGH)]. CID pathways of [CuII(GGH)]-/+ adducts instead took place mainly through intramolecular electron-transfer reactions comprising the reduction of Cu(II) to Cu(I) and the formation of fragment radical cations.


Assuntos
Aminoácidos/química , Cobre/química , Citotoxinas/química , Peptídeos/química , Fosfinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Aminoácidos/análise , Sítios de Ligação , Cobre/análise , Citotoxinas/análise , Peptídeos/análise , Fosfinas/análise , Ligação Proteica
10.
Anal Chim Acta ; 891: 73-8, 2015 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26388365

RESUMO

An inductively coupled plasma mass spectrometry (ICPMS) coupled with gas to particle conversion-gas exchange technique was applied to the direct analysis of ultra-trace semiconductor gas in ambient air. The ultra-trace semiconductor gases such as arsine (AsH3) and phosphine (PH3) were converted to particles by reaction with ozone (O3) and ammonia (NH3) gases within a gas to particle conversion device (GPD). The converted particles were directly introduced and measured by ICPMS through a gas exchange device (GED), which could penetrate the particles as well as exchange to Ar from either non-reacted gases such as an air or remaining gases of O3 and NH3. The particle size distribution of converted particles was measured by scanning mobility particle sizer (SMPS) and the results supported the elucidation of particle agglomeration between the particle converted from semiconductor gas and the particle of ammonium nitrate (NH4NO3) which was produced as major particle in GPD. Stable time-resolved signals from AsH3 and PH3 in air were obtained by GPD-GED-ICPMS with continuous gas introduction; however, the slightly larger fluctuation, which could be due to the ionization fluctuation of particles in ICP, was observed compared to that of metal carbonyl gas in Ar introduced directly into ICPMS. The linear regression lines were obtained and the limits of detection (LODs) of 1.5 pL L(-1) and 2.4 nL L(-1) for AsH3 and PH3, respectively, were estimated. Since these LODs revealed sufficiently lower values than the measurement concentrations required from semiconductor industry such as 0.5 nL L(-1) and 30 nL L(-1) for AsH3 and PH3, respectively, the GPD-GED-ICPMS could be useful for direct and high sensitive analysis of ultra-trace semiconductor gas in air.


Assuntos
Poluentes Ocupacionais do Ar/análise , Arsenicais/análise , Gases/análise , Espectrometria de Massas/métodos , Fosfinas/análise , Semicondutores , Amônia/química , Limite de Detecção , Ozônio/química , Tamanho da Partícula
11.
Medicine (Baltimore) ; 94(38): e1637, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26402837

RESUMO

Metal phosphides such as aluminum phosphide are potent insecticides. This highly toxic substance is used for rice and other grains protection in Iran. Due to its high toxicity potential and easy availability, it is widely used as a suicide poison. This substance has no effective antidote and the incidence of deaths due to its poisoning is increasing day by day in Iran. The present study was conducted to show the increasing incidence of fatal aluminum phosphide poisoning and its toxicological and forensic aspects in an 8-year study, 2006 to 2013. Autopsy sheets were reviewed and cases with the history of aluminum phosphide poisoning were selected. Toxicological analysis results, demographic and necroscopic examination findings were studied. A total of 51.8% of studied cases were female. Most of the cases were between 10 and 40 years old. The manner of death was self-poisoning in 85% of cases. Morphine, ethanol, and amitriptyline were the most common additional drugs detected in toxicological analysis. The incidence of fatal aluminum phosphide poisoning cases referred for phosphine analysis was 5.22 and 37.02 per million of population of Tehran in 2006 and 2013, respectively. The results of this study showed that in spite of ban and restrictions, there was a dramatic increase in the incidence of fatal aluminum phosphide poisoning in Tehran from 2006 to 2013. Safety alert should be highlighted in training program for all population groups about the toxic effects of aluminum phosphide tablets.


Assuntos
Compostos de Alumínio/intoxicação , Praguicidas/intoxicação , Fosfinas/intoxicação , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos Transversais , Feminino , Toxicologia Forense , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Fosfinas/análise , Intoxicação/mortalidade , Estudos Retrospectivos , Suicídio , Adulto Jovem
12.
J Forensic Sci ; 60(3): 818-21, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25707792

RESUMO

Aluminum phosphide is one of the commonest poisons encountered in agricultural areas, and manner of death in the victims is often suicidal and rarely homicidal or accidental. This paper presents an unusual case, where two humans (owner and housemaid) and eight dogs were found dead in the morning hours inside a room of a house, used as shelter for stray dogs. There was allegation by the son of the owner that his father had been killed. Crime scene visit by forensic pathologists helped to collect vital evidence. Autopsies of both the human victims and the dogs were conducted. Toxicological analysis of viscera, vomitus, leftover food, and chemical container at the crime scene tested positive for aluminum phosphide. The cause of death in both humans and dogs was aluminum phosphide poisoning. Investigation by police and the forensic approach to the case helped in ascertaining the manner of death, which was accidental.


Assuntos
Acidentes , Compostos de Alumínio/intoxicação , Praguicidas/intoxicação , Fosfinas/intoxicação , Adulto , Idoso , Compostos de Alumínio/análise , Animais , Cromatografia Gasosa , Cães , Análise de Alimentos , Patologia Legal , Toxicologia Forense , Humanos , Masculino , Praguicidas/análise , Fosfinas/análise , Espectrofotometria Atômica , Espectroscopia de Infravermelho com Transformada de Fourier , Vômito
14.
Environ Sci Technol ; 48(6): 3372-7, 2014 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-24568676

RESUMO

This study explores catalytic decomposition of phosphine (PH3) using iron group metals (Co, Ni) and metal oxides (Fe2O3, Co(3)O4, NiO) supported on carbon nanotubes (CNTs). The catalysts are synthesized by means of a deposition-precipitation method. The morphology, structure, and composition of the catalysts are characterized using a number of analytical instrumentations, including high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, BET surface area measurement, and inductively coupled plasma. The activity of the catalysts in the PH3 decomposition reaction is measured and correlated with their surface and structural properties. The characterization results show that phosphidation occurs on the catalyst surface, and the resulting metal phosphides act as an active phase in the PH3 decomposition reaction. Cobalt phosphide, CoP, is formed on Co/CNTs and Co(3)O4/CNTs, whereas iron phosphide, FeP, is formed on Fe2O3/CNTs. In contrast, phosphorus-rich phosphide NiP2 is formed on Ni/CNTs and NiO/CNTs. The initial activities of the catalysts are shown in the following sequence: Ni/CNTs > Co/CNTs > Co(3)O4/CNTs >NiO/CNTs > Fe2O3/CNTs, whereas activities of metal phosphides are shown in the following order: CoP > NiP2 > FeP. The catalytic activity of metal phosphides is attributed to their electronic properties. Cobalt phosphide formed on Co/CNTs and Co(3)O4/CNTs exhibits not only the highest activity, but also long-term stability in the PH3 decomposition reaction.


Assuntos
Poluentes Atmosféricos/química , Recuperação e Remediação Ambiental/instrumentação , Recuperação e Remediação Ambiental/métodos , Metais Pesados/química , Nanotubos de Carbono/química , Fosfinas/química , Poluentes Atmosféricos/análise , Compostos Férricos/química , Óxidos/química , Fosfinas/análise
15.
J Environ Sci (China) ; 22(9): 1309-11, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21174959

RESUMO

Phosphine is a part of an atmospheric link of phosphorus cycle on earth, which could be an important pathway for phosphorus transport in environment. Wetland ecosystems are important locations for global biogeochemical phosphorus cycle. In this study, production and emission fluxes of free phosphine from four wetlands types in southern China were observed in different seasons. The results showed that the concentration of phosphine liberated from wetlands was at pg/m3-ng/m3 level. The emission concentrations of different wetlands followed the sequence: paddy field (51.83 +/- 3.06) ng/m3 > or = marsh (46.54 +/- 20.55) ng/m3 > lake (37.05 +/- 22.74) ng/m3 >> coastal wetland (1.71 +/- 0.73) ng/m3, the positive phosphine emission flux occurred in rice paddy field (6.67 +/- 5.18) ng/(m2 x hr) and marsh (6.23 +/- 26.9) ng/(m2 x hr), while a negative phosphine flux of (-13.11 +/- 35.04) ng/(m2 x hr) was observed on the water-air interface of Lake Taihu, suggesting that paddy field and marsh may be important sources for phosphine gas in atmosphere, while lake may be a sink of atmospheric phosphine gas during the sampling period. Atmospheric phosphine levels and emission flux from Yancheng marsh and rice paddy field varied in different seasons and vegetational zones. Both diffusion resistance in aqueous phase and temperature were dominating factors for the production and transportation of phosphine to atmosphere.


Assuntos
Monitoramento Ambiental , Fosfinas/análise , Áreas Alagadas
16.
J Chromatogr A ; 1217(52): 8298-307, 2010 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-21084090

RESUMO

Fumigants and volatile industrial chemicals are particularly hazardous to health when a freight container is fumigated or the contaminated material is introduced into its enclosed environment. Phosphine is now increasingly used as a fumigant, after bromomethane--the former fumigant of choice--has been banned by the Montreal Protocol. We have enhanced our previously established thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) method by integrating a second gas chromatographic dimension and a flame photometric detector to allow the simultaneous detection of phosphine and volatile organic compounds (VOCs), providing a novel application. A thermal desorption system is coupled to a two dimensional gas chromatograph using both mass spectrometric and flame photometric detection (TD-2D-GC-MS/FPD). Additionally, the collection of mass spectrometric SIM and Scan data has been synchronised, so only a single analysis is now sufficient for qualitative scanning of the whole sample and for sensitive quantification. Though detection limits for the herewith described method are slightly higher than in the previous method, they are in the low µL m(-3) range, which is not only below the respective occupational exposure and intervention limits but also allows the detection of residual contamination after ventilation. The method was developed for the separation and identification of 44 volatile substances. For 12 of these compounds (bromomethane, iodomethane, dichloromethane, 1,2-dichlorethane, benzene, tetrachloromethane, 1,2-dichloropropane, toluene, trichloronitromethane, ethyl benzene, phosphine, carbon disulfide) the method was validated as we chose the target compounds due to their relevance in freight container handling.


Assuntos
Poluentes Atmosféricos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Inseticidas/análise , Fosfinas/análise , Compostos Orgânicos Voláteis/análise , Fumigação/efeitos adversos , Cromatografia Gasosa-Espectrometria de Massas/instrumentação
17.
J Forensic Leg Med ; 16(6): 312-5, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19573839

RESUMO

Fatalities resulted from aluminium phosphide (ALP) intoxication in completely healthy children with no preceded clinical sings or symptoms were presented. Data regarding circumstances, autopsy reports, histopathological examination, toxicological investigation, and police enquiries were also collected and evaluated. The affected children were females, and 6-16 years old. They were completely healthy and died suddenly in relation to some physical activities such as running, walking, and bathing, without any prior complain. The viscera showed intense congestion with moderate to severe pulmonary edema. The cause of the sudden termination of life in the reported cases is mostly cardiac ones. Physical exertion may precipitate death due to increased cardiac stress, increased oxygen demand, and by aggravating metabolic acidosis. The absence of clinical symptoms before death may be due to the low level ALP, or due to the occurrence of death in the early stages after exposure to poison. Death due to ALP could result in cases of mild, moderate, or severe ALP intoxication. This may explain partly the differences encountered in clinical, autopsy, and histopathology findings of ALP intoxication. Fatalities are not the mere consequences of the dose of the poison, but factors such as physical activity and low oxygen level may be quite important.


Assuntos
Compostos de Alumínio/intoxicação , Banhos , Praguicidas/intoxicação , Fosfinas/intoxicação , Corrida , Caminhada , Acidentes , Doença Aguda , Adolescente , Carboxihemoglobina , Criança , Morte Súbita/etiologia , Exposição Ambiental/efeitos adversos , Feminino , Patologia Legal , Toxicologia Forense , Conteúdo Gastrointestinal , Insuficiência Cardíaca/etiologia , Hemorragia/patologia , Humanos , Exposição por Inalação/efeitos adversos , Fígado/química , Miocárdio/patologia , Neutrófilos/patologia , Fosfinas/análise , Edema Pulmonar/patologia
18.
Methods Enzymol ; 457: 149-65, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19426867

RESUMO

While palmitoylation is typically thought of as a cytosolic process resulting in membrane attachment of the palmitoylated proteins, numerous mitochondrial proteins have been shown to be palmitoylated following in vitro labeling of mitochondria with radioactive or bioorthogonal analogues of fatty acids. The fatty acylation of two liver mitochondrial enzymes, methylmalonyl semialdehyde dehydrogenase and carbamoyl phosphate synthetase 1, has been studied in great detail. In both cases palmitoylation of an active site cysteine residue occurred spontaneously and resulted in inhibition of enzymatic activity, thus, suggesting that palmitoylation may be a direct means to regulate the activity of metabolic enzymes within the mitochondria. The progress of investigators working on protein fatty acylation has long been impeded by the long exposure time required to detect the incorporation of [(3)H]-fatty acids into protein by fluorography (often 1-3 months or more). Significant reduction in exposure times has been achieved by the use of [(125)I]-iodofatty acids but these analogues are also hazardous and not commercially available. Herein, we describe a sensitive chemical labeling method for the detection of palmitoylated mitochondrial proteins. The method uses azido-fatty acid analogues that can be attached to proteins and reacted with tagged phosphines via a modified Staudinger ligation. Recently, we used this labeling method, combined with mass spectrometry analysis of the labeled proteins, to identify 21 palmitoylated proteins from rat liver mitochondria.


Assuntos
Acil Coenzima A/análise , Azidas/análise , Lipoilação , Mitocôndrias Hepáticas/metabolismo , Proteínas Mitocondriais/análise , Proteínas Mitocondriais/metabolismo , Acil Coenzima A/síntese química , Acil Coenzima A/química , Acilação , Animais , Azidas/síntese química , Azidas/química , Cromatografia , Cisteína/análise , Cisteína/metabolismo , Espectrometria de Massas , Mitocôndrias Hepáticas/química , Proteínas Mitocondriais/química , Proteínas Mitocondriais/isolamento & purificação , Ácido Palmítico/análise , Ácido Palmítico/síntese química , Ácido Palmítico/química , Fosfinas/análise , Fosfinas/síntese química , Fosfinas/química , Ratos , Ratos Sprague-Dawley
19.
Forensic Sci Int ; 177(2-3): e35-8, 2008 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-18294792

RESUMO

In a suicide committed using aluminium phosphide (AlP) the liberated toxic phosphine gas was detected in post-mortem specimens using a headspace gas chromatographic procedure with a nitrogen-phosphorous detector (HS-GC/NPD). At autopsy a direct sampling into airtight headspace vials for a later analysis is recommended. AlP has to be considered a potent pesticide and its use and availability should be restricted as much as possible.


Assuntos
Compostos de Alumínio/análise , Praguicidas/análise , Fosfinas/análise , Suicídio , Adulto , Compostos de Alumínio/intoxicação , Cromatografia Gasosa , Patologia Legal , Toxicologia Forense , Conteúdo Gastrointestinal/química , Humanos , Intestino Delgado/química , Masculino , Mucosa Nasal/química , Praguicidas/intoxicação , Fosfinas/intoxicação
20.
Pest Manag Sci ; 63(1): 96-103, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17051623

RESUMO

Owing to increased tolerance and the development of resistance in stored product insects to the fumigant phosphine, in recent years there has been a shift in the target terminal concentration from 100 ppm (100 mL m(-3)) to a higher level of 1000 ppm to achieve 100% insect mortality in 7 day commodity treatments. Therefore, there is a need to investigate whether the revised target concentration could be achieved for food commodities fumigated with phosphine at the standard dose of 2 g m(-3) for 7 days under airtight conditions at > or = 25 degrees C. When different types of food commodity (total 74) were fumigated (300 g per replicate) with phosphine at 2 g m(-3) for 7 days, the terminal gas concentrations in the free space of the commodities varied from 0 to > 2000 ppm. In chambers containing no substrate, a 1417 ppm concentration was recorded. Paddy rice, most of the oilseeds, shelled tree nuts, butter beans, cardamom, green gram splits, coriander powder, rice bran and cocoa powder were more sorptive (> or =60%), such that the target concentration of 1000 ppm was not achieved at the end of 7 days. For these commodities, increased doses of 3-6 g m(-3) were required to attain 1000 ppm. In-shell almonds, green cardamom, in-shell peanuts, leaf tea, tamarind pulp and sunflower seeds were exceptionally sorptive (>90%), so that 0, 41, 112, 168, 203 and 217 ppm respectively were noted at the end of 7 days; the dose must exceed 6 g m(-3) for effective fumigation of these commodities.


Assuntos
Análise de Alimentos , Fumigação/normas , Inseticidas/análise , Resíduos de Praguicidas/análise , Fosfinas/análise , Adsorção , Parasitologia de Alimentos , Controle de Pragas/normas
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