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PubMed1985

Change in the volatile fatty acids content of laboratory stored sterilized and non-sterilized swine wastes.

The influence of urine and microbial activity was studied as possible factors leading to the generation of volatile fatty acids in non-sterilized stored swine wastes. Urine was found to promote the generation of the volatile acids. The microbial origin of the volatile acids in the wastes was ascertained by the growth of an anaerobic bacterial strain (Peptostreptococcus anaerobius). Significant generation and transformation of these acids was observed in sterilized swine waste samples stored under conditions similar to the non-sterilized samples.

Animals↗
PubMed1984

Survey of resistance to metals and volatilization activity of Hg-resistant R plasmids in Citrobacter isolated from clinical lesions in Japan.

Clinical isolates of Citrobacter (277 strains) were studied for the resistance to four metals and four drugs. The distribution patterns of their susceptibility to Hg, Cd and As clearly revealed two peaks, but only a single peak of resistance to Pb. The frequencies of resistance to Hg, Cd, As, SM, TC, CP and KM were 31.8, 94.2, 57.8, 51.3, 44.8, 35.7 and 28.9%, respectively. And we selected 88 mercury resistant strains, and they were tested for their ability to transfer the resistance to the mercury and drug sensitive recipients of E. coli K12-ML1410-Nx and E. coli JE17-Rif. Among 88 strains of Hg resistant Citrobacter, 80 R plasmids with Hg resistance could be demonstrated. It should be noted that transferable R plasmids with Hg resistance were demonstrated in 91% of the Hg-resistant isolates. Furthermore, we tested the volatilization of mercury by strains containing these mercury resistance plasmids, by using radioactive 203Hg2+. All of these isolates of Citrobacter have volatilization activity of Hg2+. Also, all of these volatilization activity is inducible.

Anti-Bacterial Agents↗
PubMed1984

Formation of volatile nitrosamines by drug-nitrite interactions under physiological conditions.

Twenty-eight drugs, most of which are tertiary amines, were tested for the formation of volatile nitrosamines by reaction with nitrite under physiological conditions; the drugs (10mM) were incubated with nitrite ( 40mM ) at pH 3.0, 37 degrees for 1 and 4 hr. The volatile nitrosamines formed were determined by gas chromatography-thermal energy analysis. Of the 28 drugs, 24 formed measurable amounts of volatile nitrosamines that are known carcinogens. The yields of nitrosodimethylamine (NDMA) from aminopyrine (55-65%) and minocycline (11%) were higher than that from dimethylamine under the same conditions. This result suggests that there may be a pathway not involving the secondary amine (dimethylamine) as an intermediate in the formation of NDMA from minocycline as well as from aminopyrine, Tolazamide gave rise to nitrosopiperidine ( NPIP ) in addition to nitrosohexamethyleneimine ( NHXI ), formation of which was expected from the chemical structure of tolazamide, and the yield of NPIP (2-7%) was higher than that of NHXI (0.2-1.2%). Ascorbic acid ( 40mM ) was effective in decreasing the formation of nitrosamines from drugs by reaction with nitrite, although the blocking effects varied between 88 and 100% depending on the drugs tested or on the nitrosamines formed.

Amines↗
PubMed1981

The role of organic volatile profiles in clinical diagnosis.

The organic volatile constituents of biological fluids contain clinically useful diagnostic information for the recognition of metabolic disorders in man. To gain access to this information, it was necessary to develop the methodology for reproducibly stripping the trace concentrations of volatiles from biological fluids (dynamic headspace, gas phase-stripping, solvent extraction, and the transevaporator technique), to separate the complex extracts by high-resolution capillary column gas chromatography, and to develop computer-aided data-handling and pattern-recognition techniques for analyzing the immense amount of information generated. The normal and pathological organic volatiles identified by gas chromatography--mass spectrometry in urine, serum, and breast milk are tabulated. Clinical applications of the above techniques to the study and diagnosis of diabetes mellitus, respiratory virus infection, renal insufficiency, and cancer are described.

Alcohols↗
PubMedDate not supplied

[Dynamics of the accumulation and retention of volatile organic substances released by bacteria].

The object of this work was to study the production of volatile biologically active compounds by microorganisms and their accumulation in the medium in the course of several days. The inhibiting action of the accumulated volatile metabolites was found to depend on the time within which the culture was incubated and on the sensitivity of the test organism. The activity of the accumulated metabolites was shown to decrease with the time of storage. Several volatile compounds were found among the metabolites.

Anti-Bacterial Agents↗
PubMed1994

Volatile substance abuse.

Volatile substance abuse (VSA) (glue sniffing, inhalant abuse, solvent abuse), the deliberate inhalation of volatile substances in order to achieve intoxication, has now been reported from most parts of the world, mainly among adolescents, individuals living in remote communities and those whose occupations give ready access to abusable substances. Solvents from contact adhesives, notably toluene, petrol (gasoline), halogenated solvents, volatile hydrocarbons such as those found in cigarette lighter refills, aerosol propellants, halocarbon fire extinguishers, and inhalational anaesthetics may be abused in this way. VSA gives rise to dose-related effects similar to those of other hypnosedatives. Small doses can rapidly lead to euphoria and other disturbances of behaviour similar to those caused by ethanol (alcohol), and may also induce delusions and hallucinations. Higher doses may produce life-threatening effects such as convulsions and coma. Death may ensue indirectly after, for example, inhalation of vomit, or from direct cardiac or central nervous system toxicity. Chronic abuse of toluene-containing products and of chlorinated solvents such as 1,1,1-trichloroethane, for example, can produce severe organ damage, especially in the liver, kidneys, and brain. Drunken behaviour, unexplained listlessness, anorexia and moodiness may result from VSA, especially in children and adolescents. The hair, breath and clothing may smell of solvent, and empty adhesive tubes or other containers, potato crisp bags, cigarette lighter refills, and aerosol spray cans are often found. Toxicological examination of blood and tissue specimens is especially important in confirming a diagnosis of sudden VSA-related death. The development and evaluation of strategies for the treatment of chronic abusers and for prevention are major challenges for the future.

Death, Sudden↗
PubMed1994

[The occurrence of organic volatile compounds in a sample room of a new building in relation to the "natural" air exchange].

The occurrence of certain volatile organic compounds was to be investigated in a sample room of a new building to determine any health hazard arising from the employed materials. Approximately 60 volatile organic compounds, formaldehyde, polychlorinated biphenyls, inorganic fibrous particles and "natural" air-exchange were included in the investigation. The reasons for increased concentrations of formaldehyde and volatile organic compounds could be determined by material-emission-investigations. These investigations further revealed that medical-hygienic demands for sufficient "natural" air-exchange should possibly be given priority over warmth conservation regulations (Wärmeschutzverordnung) that require a high degree of insulation in windows and doors. If this is not taken into consideration then some of the staff may display a variety of symptoms known as "sick-building-syndrome".

Air Conditioning↗
PubMedDate not supplied

Determination of volatile organic contaminants in bulk oils (edible, injectable, and other internal medicinal) by purge-and-trap gas chromatography/mass spectrometry.

Purge-and-trap gas chromatography/mass spectrometry is evaluated for the quantitation of part-per-billion levels of volatile organic contaminants in bulk vegetable oils. Results using 2 purge techniques (direct purging of the heated oil and purging after dispersing the oil on an aluminum oxide powder) and 2 quantitative methods (standard curve and deuterium-labeled internal standard addition) are reported. Twenty volatile compounds and 8 vegetable oils were investigated. Recovery data and estimated detection limits for each compound are reported for each purge technique. Generally acceptable recoveries (70-130% for more than 90% of the analyte spikes) and acceptable detection levels (approximately 4-10 ppb) were obtained for all compounds using either the external standard curve or the deuterium-isotope-labeled internal standard. The use of a dispersant (such as alumina) for sample purging resulted in poor recoveries of the highly volatile contaminants.

Aluminum Oxide↗
PubMedDate not supplied

Estimated content percentages of volatile liquids and fat extractables in ready-to-eat foods.

Content percentages of volatile liquids and fat extractables in 340 samples of ready-to-eat foods were determined gravimetrically. Volatile liquids were determined by drying samples in a microwave oven with a self-contained balance; results were printed out automatically. Fat extractables were extracted from the samples with mixed ethers; extracts were dried and weighed manually. The samples, 191 nonfat and 149 fatty (containing ca 2% or more fat) foods, represent about 5000 different food items and include infant and toddler, ethnic, fast, and imported items. Samples were initially prepared for screening of essential and toxic elements and chemical contamination by chopping and mixing into homogenous composites. Content determinations were then made on separate portions from each composite. Content results were put into a database for evaluation. Overall, mean results from both determinations agree with published data for moisture and fat contents of similar food items. Coefficients of variation, however, were lower for determination of volatile liquids than for that of fat extractables.

Chromatography, Gas↗
PubMedDate not supplied

On-line steam distillation/purge and trap analysis of halogenated, nonpolar, volatile contaminants in foods.

An on-line, steam distillation/purge and trap gas chromatographic procedure is described for determination of halogenated analytes in foods and beverages. Recoveries were generally >80% (versus aqueous standards) from vegetable oil, flour, root beer, cream (10% butter fat), and milk spiked at 1-3 micrograms/kg for each of the 32 analytes studied. Analytes ranged in volatility from vinyl chloride to 1,2,3,4-tetrachlorobenzene. Repeatabilities from aqueous standards were <10% for most analytes. For a 1 g food sample, method detection limits ranged from 0.02 to 0.2 micrograms/kg for the 32 analytes. Reduced recoveries for less volatile analytes, however, occurred when steam-distillable, nonpolar food components were carried to the sparger. This effect was observed for citrus beverages containing steam-volatile limonene, roasted and ground coffees, and some salad dressings. The method was applied to a variety of foods.

Chromatography, Gas↗
PubMed1996

A novel approach to study antibacterial properties of volatile components of selected Indian medicinal herbs.

The aromatic substances of natural origin are used medicinally in Ayurveda, and can have diverse bio-dynamic actions. The existing methods like agar-cup method or disc diffusion method are not adequate to study the exclusive antibacterial effects of the volatile components of aromatic oils due to lack of ideal diffusion and evaporation from the surface. Hence an attempt is made to develop a novel approach to assess the antibacterial activity of few aromatic herbs like Eugenia caryophyllus, Thymus vulgaris, Cinnamonum zeylanium, Cuminum cyminum; these were extracted with hexane filled in tiny sterile tubes and the volatile components were tested for their antibacterial properties using standard strains of gram +ve and gram -ve bacteria grown on agar slants. The results are expressed as a percent of inhibition of the area on the slants, from the top of the extract tube. Of the four herbs selected, volatile components of Thymus vulgaris were most effective againsts all the seven test organisms.

Anti-Bacterial Agents↗
PubMed1998

The effect of the volatile oils of Chenopodium ambrosioides and Thymus vulgaris against the larvae of Lucilia sericata (Meigen).

Nowadays, there are many problems with the use of chemical insecticides as resistance, environmental pollution, toxicity to man and animal... etc. All these required the investigation of a new line for controlling arthropod pests of medical and agricultural importance. The volatile oils of Chenopodium ambrosioides (American wormseed) and Thymus vulgaris (Tyme) proved to be effective against the third stage larvae of Lucilia sericata. The LC50 confidence limits were 70 ppm and 130 ppm for both volatile oils respectively. No doubt, the use of these plant volatile oils, which are widely distributed in the Egyptian flora, more cheap, more safe and without any pollution or hazard, is recommended.

Animals↗
PubMedDate not supplied

Rapid determination of volatile bases in fish by using an ammonia ion-selective electrode.

A simple and rapid method using an ammonia ion-selective electrode (ISE) to measure volatile bases in fish is proposed. Accuracy and precision were determined with 5, 10, 20, and 30 ppm NH3 standard solutions. Ammonia values obtained with the method correlate strongly with total volatile basic nitrogen (r2 = 0.88). Recoveries of added ammonia to homogenized fish samples ranged from 83.7 to 96.0%. Responses of the probe to trimethylamine (TMA), calculated as NH3 (mg/100 mL), ranged from 74.9 to 91.7%. These findings indicate that the probe measured TMA as well as ammonia. Storage trials on 8 fish species illustrated that the results obtained with the ISE method reflected nitrogen concentrations based on total volatile base (TVB) analysis. This procedure may be used in lieu of the traditional TVB method for on-site rapid screening of fish.

Ammonia↗
PubMed1994

Rush hemolysis. A 'bite-cell' hemolytic anemia associated with volatile liquid nitrite use.

Volatile nitrites are illegally marketed compounds that have been inhaled by persons who believe that they cause sexual arousal. These substances have been associated with significant hemolysis of red blood cells in patients with decreased or normal glucose-6-phosphate dehydrogenase levels because such nitrites act as cell-membrane oxidants. We report herein a case of hemolysis in a patient with an underlying glucose-6-phosphate dehydrogenase deficiency associated with the use of volatile nitrites, and we also review the literature of volatile nitrite-induced hemolytic anemia.

Adolescent↗
PubMed2002

Dietary exposure and urinary excretion of total N-nitroso compounds, nitrosamino acids and volatile nitrosamine in inhabitants of high- and low-risk areas for esophageal cancer in southern China.

We assessed the exposure of total N-nitroso compounds (TNOCs) in the inhabitants of high- and low-risk areas for esophageal cancer in southern China. Samples of 24 hr diet and 12 hr overnight urine were collected from 120 male adults in each of the 2 areas, a high-risk area (Nan'ao County) and a low-risk area (Lufeng County) for esophageal cancer. Annual standardized mortality rates of esophageal cancer in Nan'ao and Lufeng are 110/10(6) and 10/10(6) respectively. The 240 healthy male subjects (35-64 years old) were selected by a 3-stage random cluster sample procedure. Levels of TNOCs, NAAs and volatile nitrosamines in the samples were measured. The TNOC detection rate (95%) in the diet, the TNOC daily intake (4.25 +/- 0.84 micromol), TNOC excretion levels (0.04 +/- 0.01 nmol/12 hr) and daily intake of volatile nitrosamines (5.84 +/- 0.71 micromol) in the high-risk area were significantly greater than values in the low-risk area (A +/- B = mean +/- SE). The TNOC detection rate in the diet, the TNOC daily intake, TNOC excretion levels and daily intake of volatile nitrosamines in the low-risk area were 70%, 0.25 +/- 0.06 micromol, 0.02 +/- 0.01 nmol/12 hr and 3.18 +/- 0.31 micromol, respectively. NAA excretion levels showed no difference between the 2 areas (16.3 +/- 7.18 micromol/12 hr for Nan'ao and 31.2 +/- 26.4 micromol/12 hr for Lufeng). Thus, TNOCs are implicated in the etiology of esophageal cancer in southern China.

Adult↗
PubMed1990

In vivo percutaneous absorption studies of volatile organic solvents in hairless mice. II. Toluene, ethylbenzene and aniline.

Percutaneous absorption studies were conducted with three single-ring, radiolabeled aromatic solvents (benzene derivatives) using a recently described direct method for studying volatile chemicals in hairless mice. Total absorption, determined from the sums of radioactivity found in the excreta, expired breath and carcass, was 2.1+, 3.4% and 4.7% of the nominal dose for toluene, ethylbenzene and aniline, respectively. Breath decay curves indicated that absorption of toluene and ethylbenzene was complete by 15 min after application and that by this time the excretion rate of aniline exceeded the absorption rate. Evaporation rates were used to derive estimated contact times, and these in turn were used in conjunction with the absorbed doses to estimate percutaneous absorption rates. Equivalent dermal exposures (cm2.min) that would yield body burdens equivalent to those expected following 8-h inhalations at existing US permissible exposure limits during light work were calculated. The data indicate that dermal absorption of these compounds could approach or exceed that from inhalation under some work conditions. Correlations between absorption and various physical properties were evaluated using Spearman's correlation coefficients. The physical properties evaluated included volatility, solubility, octanol/water partition coefficients and melting points. For this limited series of benzene derivatives, two measures of volatility, i.e. vapor pressure and boiling point, were the only physical properties significantly correlated with percutaneous absorption.

Aniline Compounds↗
PubMed2004

Elution and preliminary structure-retention modeling of polar and ionic substances in supercritical fluid chromatography using volatile ammonium salts as mobile phase additives.

Supercritical fluid chromatography has primarily been applied to relatively nonpolar analytes, even when polar organic solvents are used as modifiers. Here, we show that low levels of volatile ammonium salts as mobile-phase additives allow the elution of polar and even ionic organic materials such as sulfonate salts, carboxylate salts, polyamines, and quaternary ammonium salts. Also, volatile ammonium salts are compatible with mass spectrometric detection, in contrast to other common additives. We have performed preliminary structure-activity-relationship modeling for retention in the CO2/methanol/NH4OAc/Deltabond Cyano system. We have developed a three-descriptor model, where one descriptor, the "relative negative charged surface" explains over 61% of the variance in the retention values. We suggest that two mechanisms have the greatest influence on retention in this system. One is related to the presence of a volatile ammonium salt, the other is related to the ability of a molecule to "hide" its atom with the greatest partial negative charge.

Journal Article↗
PubMed2002

Quantification of volatile compounds in the headspace of aqueous liquids using selected ion flow tube mass spectrometry.

We describe a method by which the concentrations of volatile compounds in the headspace of their dilute aqueous solutions in sealed containers can be determined using on-line selected ion flow tube mass spectrometry (SIFT-MS). Thus, the changing number density of the molecules of the volatile compound in the carrier gas of the SIFT-MS instrument is described in terms of its changing flow rate as the pressure in the sealed container decreases during the sampling procedure. It is shown that the best analytical procedure is to determine the mean concentration of the trace gas in the liquid headspace over a given sampling time and relate this to the required concentration, which is the initial equilibrium concentration established before the pressure in the sealed container reduces significantly. To test the validity of this analytical approach, the headspace concentrations of acetaldehyde, ethanol and acetone above aqueous solutions of known concentrations have been determined. Hence, the Henry's Law constants for these compounds have been determined and found to agree with the published values. The confirmation of the quality of this sampling methodology combined with SIFT-MS for the analysis of volatile compounds in liquid headspace paves the way for the rapid analyses of biological liquids such as urine and serum for clinical diagnosis and physiological monitoring.

Journal Article↗