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An evaluation of Fourier transform infrared (FTIR) spectroscopy for detecting organic solvents in expired breath.

The aim of this study was to test the performance of gas-phase FTIR analysis on human breath samples. Ten volatile organic compounds (VOC) were examined for applicability to FTIR spectroscopy (ethanol, ethylbenzene, n-hexane, methyl ethyl ketone, methyl tert-butyl ether, m-xylene, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, and toluene). Three sets of detection limits (LOD) were determined for comparison. LOD(1) were generated from partial least squares (PLS) calibration methods using spectroscopic software, LOD(2) from spiked breath samples, and LOD(3) from blank breath sam

Thermodynamics of the distribution of some carboxylic acids between organic solvents and a perchlorate solution.

The distribution of formic, benzoic and 4-methylbenzoic acids between a 0.1 mol dm(-3) (Na+, H+)ClO4- solution and octanol and carbon tetrachloride was studied at five different temperatures of 10 - 30 degrees C. The thermodynamic parameters for the transfer process of monomeric acid between two phases and for the dimerization of monomeric acid in carbon tetrachloride (deltaH and deltaS) were evaluated from the van't Hoff isochore. The free-energy change for the transfer of a methylene group from water to organic solvents was entropically controlled, irrespective of the organic solvents. The d…

[Identification and quantitative determination of chlorinated++ solvents after solid phase microextraction. Applications in hospital toxicology].

A simple method for the research and the identification of chlorinated solvents in biological fluids and tissues is described. The solvents are extracted using headspace solidphase microextraction and detected or measured by gas chromatography with electron capture detector. Three accidental poisonings are reported: one with carbon tetrachloride, one with trichlorethylene and the last one is a double intoxication with tetrachloroethylene and trichlorethylene.

PET scan findings in a patient with a remote history of exposure to organic solvents.

This is a single-case study employing positron emission tomography (PET) scanning and neuropsychological assessment on a 47-year-old male with a 15-year history of repeated respiratory and dermal exposure to high levels of organic solvents with at least 750 peak exposures (i.e., solvent "intoxication"). At age 43, he presented with neuropsychological symptoms of a solvent encephalopathy and multiple abnormalities in his peripheral neurological examination but had normal MRI and EEG findings. Four years after cessation of exposure to degreasing and solvent chemicals, the patient produced a gros…

Cometabolism of chlorinated solvents by nitrifying bacteria: kinetics, substrate interactions, toxicity effects, and bacterial response.

Pure cultures of ammonia-oxidizing bacteria, Nitrosomonas europaea, were exposed to trichloroethylene (TCE), 1,1-dichloroethylene (1,1-DCE), … quite readily and showed no inactivation effects. Recovery capabilities were demonstrated with all solvents except CF. A method for estimating protein yield, the relationship between the transformation capacity model and the IIR model, and a condition necessary for sustainable cometabolic treatment of inactivating substrates are presented. (c) 1997 John W …

[Exposure to solvents in scleroderma: disseminated circumscribed scleroderma (morphea) in a painter exposed to perchloroethylene].

We report on a 45-year-old painter who developed morphea-like scleroderma. He had been exposed to perchlorethylene for one year while operating a metal degreaser; the perchlorethylene concentration in the workplace ranged between 10 and 25 ppm. Whereas systemic scleroderma has frequently been attributed to solvent exposure in the past, this is only the third description of a morphea-like scleroderma suspected to be related to occupational contact with organic solvents.

Organic solvents increase membrane fluidity and affect bile flow and K+ transport in rat liver.

Following the earlier observation that inhalation of volatile lipid solvents and of narcotic gases causes cholestasis, we studied the effects of various organic solvents on bile flow, plasma membrane fluidity and potassium movement in rat liver. Both in vivo and in the isolated perfused liver, applications of CCl4, CHCl3, dichloromethane, trichloroethylene, halothane, benzene and cyclohexane elicited rapid and sustained but reversible cholestasis. A transient phase of choleresis was observed prior to and after cholestasis, during the increase and fall in liver tissue solvent concentrations, re…

[The comparative characteristics of the extractive capacity of solvents in removing aminazine from liver tissue].

Comparative assessment of extractive ability of some solvents with different physical and chemical properties is presented. Use of amphiphilic solvent acetone to isolate aminazine gave higher results. Experimental works (on dogs) showed that use of aqueous acid solutions for aminazine extraction in chemical toxicological investigation is unsuitable.

Urinary concentration, environmental concentration, and respiratory uptake of some solvents: effect of the work load.

The physical demands of the workplace differ depending on specific jobs. This implies that workers exposed to the same environmental level of an airborne contaminant can absorb different amounts of it depending on their pulmonary ventilation. Starting from the relationship between the uptake (U) and the urinary concentration of six solvents (Cu) (acetone, styrene, toluene, xylenes, methylchloroform, tetrachloroethylene) and from the equation expressing their lung uptake (U = K.V.CI.R.T) the expected values of a biological index after a given time of exposure can be derived. Such values are a f…

Extraction of acidic drugs from water and plasma: study of recovery with five different solvents.

The recovery of 28 acidic drugs from water and plasma was investigated spectrophotometrically using five different solvents for extraction: hexane, diethyl ether, toluene, n-butyl chloride, and chloroform. Nine barbiturates, three sulfonamides, four diuretics, and twelve other acidic drugs were studied. As classes, the barbiturates, the sulfonamides, and the diuretics were optimally extracted with diethyl ether from both water and plasma, while considerable variation in recovery was noted among solvents for the other drugs. In general, recoveries from water were higher than those from plasma w…

Concentration-dependent behavioral changes in mice following short-term inhalation exposure to various industrial solvents.

Mice were exposed during a 4-hr period to various concentrations of 13 aliphatic or aromatic solvents which affect primarily the central nervous system (CNS). The test compounds were benzyl chloride, butyl alcohol, chlorobenzene, cyclohexanone, 1,2-dichloroethylene, diisobutyl ketone, isopropyl acetate, methyl ethyl ketone, styrene, tetrachloroethylene, 1,1,1-trichloroethane, toluene, and ortho-xylene. After exposure, measurements were made to see whether these neurotoxicants would decrease the immobility developed in a "behavioral despair" swimming test. Each chemical was shown to reduce the …

Toxic activity of seventeen industrial solvents and halogenated compounds on human lymphocytes cultured in vitro.

Seventeen chemicals (solvents, insecticides and intermediates in the production of textiles and resins) were tested in a short-term in vitro system with human lymphocytes to determine their toxic action. The parameters studied were the tritiated thymidine uptake and cell viability in cultures grown with or without a rat liver metabolizing system (S-9 mix). Data obtained showed that 1,3-dichlorobenzene, 1,2-dichlorobenzene, hexane, 1,2-diiodoethane, 1,4-dichlorobenzene, tetrachloroethylene, 2,3-dibromopropanol, chloromethyl methyl ether, 1,2- and 1,3-dibromopropane, in order, exerted the more t…

[Evaluation of the exposure to organic solvents by means of urinalysis for metabolites (author's transl)].

The method of biological monitoring of the exposure to organic solvents by means of urinalysis is discussed. The topics include the variety of the solvents to which the method of monitoring is applicable, choice of time for urine sampling, possible correction of the results for urine density, and establishment of the biological threshold. Recent progress is reviewed in particular, in the cases of benzene, toluene, xylenes, styrene, trichloroethylene, tetrachloroethylene and 1, 1, 1-trichloroethane.

Central-nervous-system defects in children born to mothers exposed to organic solvents during pregnancy.

In a two-year study of mothers of children with congenital central-nervous-system defects and their matched-pair controls, exposure to noxious influences during pregnancy was analysed. Information on exposure was gained by interviews with all the mothers, sometimes supplemented by visits to their places of work. Significantly more case-mothers than control-mothers had been exposed to organic solvents during the first trimester of pregnancy (p less than 0.01).

Solvent dehydration with structurally engineered nanoporous graphene oxide membranes.

Pervaporation provides a selective route to high purity solvents that are indispensable for high precision industry. Here, we introduce structurally engineered nanoporous graphene oxide membranes (N-GOm), obtained by heterogeneous co-assembly of nanoporous graphene oxide (NPGO) and GO nanosheets. The NPGO nanosheet characterized by nanoporous sp3 carbon domains and oxygen functionalized groups, synergistically increases water affinity, effectively elevating the water adsorption energies (Eads). The N-GOm integrates defective sp3/sp2 heterogeneous stacked cavity to facilitate water transport, e…

Метод газовой хроматографии для количественного определения остаточных растворителей в наноформуляциях.

Описано разработку и проверку метода газовой хроматографии, который является чувствительным, быстрым и специфичным для оценки 19 распространенных растворителей класса 2 и класса 3, часто используемых в формулировке наномедицины. Проверка метода проводилась с использованием системы газовой хроматографии PerkinElmer с детектированием искровой ионизации и колонки Elite 624 Crossbond 6% цианопропилфенил-94% диметилполисилоксана или DB-Fatwax-Ultra Inert с гелием в качестве носителя. Оценены характеристики валидации, такие как линейность, восстановление при добавлении, точность метода, специфичност

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The development and validation of a sensitive, rapid, and specific gas chromatography method for the evaluation of 19 common Class 2 and Class 3 solvents frequently used in nanomedicine formulation is described. Method validation was performed using PerkinElmer's headspace gas chromatograph system with flame ionization detection and an Elite 624 Crossbond 6%…