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Results 451 - 495 of 495
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Stavric B - - 1994
It has been established that exposure to polycyclic aromatic hydrocarbons (PAHs), or more specifically benzo[a]pyrene (B[a]P), either by inhalation through cigarette smoking or by contact through occupational exposure of the lungs or skin, can result in cancerous lesions. It appears that the general population consumes more B[a]P from food than ...
Chameides W L - - 1994
Three regions of the northern mid-latitudes, the continental-scale metro-agro-plexes, presently dominate global industrial and agricultural productivity. Although these regions cover only 23 percent of the Earth's continents, they account for most of the world's commercial energy consumption, fertilizer use, food-crop production, and food exports. They also account for more than ...
Koutrakis P - - 1994
Standard ozone monitoring techniques utilize large, heavy, and expensive instruments that are not easily adapted for personal or microenvironmental monitoring. For large-scale monitoring projects that examine spatial variations of a pollutant and human exposure assessments, passive sampling devices can provide the methodology to meet monitoring and statistical goals. Recently, we ...
Kim D S - - 1993
Airborne 222Rn concentrations were surveyed to observe daily and seasonal variations in the 74 subway stations in the Seoul metropolitan area. Each station built of concrete elements usually has two or three stories underground with natural and mechanical ventilation facilities. The airborne radon level was determined three times: in July ...
Cicero-Fernández P - - 1993
Data for PM10 and TSP collected from SEDUE's (Secretary of Urban Development and Ecology) five principal air monitoring stations from March of 1988 to March of 1989 were analyzed with an emphasis on spatial and temporal distributions. The Mexico City sites consisted of a mixed residential and industrial setting in ...
Sternitzke A - - 1992
Treatment of food with wood smoke is a long-established method of preservation and flavouring food. Recently, hardwood smoke condensates, purified of polycyclic hydrocarbons, have become of importance for direct flavouring of sausage-meat. The acute toxicity of the purified phenolic fraction in mice after intraperitoneal administration was therefore investigated. The LD50 ...
Pryor W A - - 1992
We here explore the use of Criegee ozonides as markers of ozone damage to lipids in systems that model pulmonary surfactant, lung lining fluids, and/or pulmonary membranes. Ozonation of methyl oleate in hexane gives an 89% yield of the Criegee ozonide. The presence of water should reduce the yield of ...
Back S O - - 1992
The environmental importance of tropospheric polycyclic aromatic hydrocarbons (PAH) is reviewed. The impact of reducing lead on airborne PAH is indicated and the importance of monitoring both particulate and gaseous-phase PAH is demonstrated. A Brief description of a sampling regime performed from 1985 to 1987 is given. Sampling of 18 ...
Weisel C P - - 1992
Gasoline is emitted from automobiles as uncombusted fuel and via evaporation. Volatile organic compounds (VOC) from gasoline are at higher levels in roadway air than in the surrounding ambient atmosphere and penetrate into automobile cabins, thereby exposing commuters to higher levels than they would experience in other microenvironments. Measurements of ...
Löfgren L - - 1991
Twenty-two volatile aromatic hydrocarbons were determined in the air of an automobile during commuting. Sampling was made on Tenax cartridges and laboratory determinations were carried out using thermal desorption combined with temperature-programmed capillary gas chromatography. Selected hydrocarbons representative of petrol exhaust were determined in the automobile and in an electric ...
Asita A O - - 1991
Smoke condensates of woods used for food preservation and aromatization in Nigeria were tested for mutagenic activity using Salmonella typhimurium TA98 and TA100. The woods were: white mangrove (Avicennia nitida), red mangrove (Rhizophora racemosa), mahogany Khaya sp.), abura (Mitragyna ciliata), alstonia (Alstonia boonei) and black afara (Terminalia ivorensis). Cigarette tar ...
Sivaswamy S N - - 1991
South Indian food dishes, comprising several deep fried items have been proved to be mutagenic. Polycyclic aromatic hydrocarbons (PAHs) such as, benzo(a)pyrene, chrysene and dibenzanthracene, which are potent and proven carcinogens have been identified and quantified in several of the commonly consumed South Indian food dishes and food components. Most ...
Lijinsky W - - 1991
Polynuclear aromatic hydrocarbons are common contaminants of processed food, usually at trace levels. These hydrocarbons are products of combustion and pyrolysis, and are present in petroleum and coal, and in products derived from them. Most polynuclear aromatic hydrocarbons are not carcinogenic, but some of them are, and a few are ...
Bush B - - 1991
Sources of burnable material within U.S. cities are analyzed. Based on a detailed evaluation of construction practices, storage of burnable contents, building function and layout, and density of buildings in city districts, we derive urban fuel load densities in terms of land use type and geographic location. Residential building fuel ...
Salman M D - - 1990
A pilot project was initiated to test an existing animal disease surveillance system for use in monitoring environmental pollutants. Eleven chlorinated hydrocarbon insecticides were assayed to provide an indication of environmental contamination. A total of 241 bovine serum samples from 53 Colorado beef ranches was tested; 123 samples (51%) were ...
Hawkins W E - - 1990
In this paper, we review studies on the carcinogenic effects of two polycyclic aromatic hydrocarbons (PAHs), benzo(a)pyrene (BaP) and 7,12-dimethylbenz(a)anthracene (DMBA), on the Japanese medaka (Oryzias latipes) and the guppy (Poecilia reticulata). Exposure media were prepared by adding PAHs to water, with and without dimethylformamide (DMF) as a carrier, and ...
de Vos R H - - 1990
Over a period of 2.5 yr, 221 different food items of a 'market basket' of 18-yr-old males were purchased every 3 months. In total, 10 market baskets were collected. The foodstuffs were prepared by normal methods and combined into 23 commodity groups. Homogenates were prepared from each commodity group, followed ...
Gilli G - - 1990
Atmospheric concentrations of volatile, halogenated hydrocarbons (VHH) can be correlated with intensity of industrial or commercial activities and with demographic density. Measurements of VHHs were performed in Turin, Italy. The VHH indoor/outdoor contamination ratio was calculated, and VHH blood concentrations were measured during 1 yr in Turin, Italy. The results ...
Madden S C - - 1989
We report the results of an initial survey in a variety of Galactic sources for cyclopropenylidene (C3H2), the first interstellar hydrocarbon ring molecule. C3H2 is found to be very widespread throughout the Galaxy. This, together with its large dipole moment and many observable transitions, makes cyclopropenylidene a promising probe for ...
Weagle G - - 1988
Normal mouse skin has a prominent fluorescence peak at 674 nm. Fluorescence emission and fluorescence excitation spectroscopy, carried out both in vitro and in vivo, led to the conclusion that the chromophore(s) responsible for this naturally occurring fluorescence is/are pheophorbide a and/or pheophytin a, degradation products of chlorophyll a that ...
Chung K - - 1988
The infrared spectra of seven commercially available posterior composite resins were analysed by ratioing the C = C aliphatic peak to the C = C aromatic peak. The degree of conversion ranged from 43.5 to 73.8%. The result was similar to the range previously obtained from unfilled Bis-GMA based resins ...
Duszynski J - - 1988
In order to study the kinetics and the nature of the interactions between the oligomycin sensitivity conferring protein (OSCP) and the F0 and F1 sectors of the mitochondrial ATPase complex, fluorescent derivatives of OSCP, which are fully biologically active, have been prepared by reaction of OSCP with the following fluorescent ...
Schenewerk M S - - 1988
A survey of well-known molecular clouds in the four strongest HCO NK-,K+ = 1(01)-0(00) hyperfine transitions has been carried out to determine the prevalence of HCO and to study its chemistry. HCO emission was observed in seven molecular clouds. Three of these, NGC 2264, W49, and NGC 7538, were not ...
Knecht U - - 1986
The increased risk of lung cancer among foundry workers is assumed to be associated with the inhalation of gaseous and particle bound polycyclic aromatic hydrocarbons (PAH). These compounds are produced during pyrolysis of carbon containing loading material in the moulding sand. The concentrations of 20 PAH, some of which are ...
Edo K - - 1986
The unstability of neocarzinostatin (NCS), apo-NCS and NCS-chromophore (NCS-chr) has been investigated by using an extra-weak chemiluminescence (CL) analyzer. A significantly high emission intensity (10,840 counts/10 seconds) was detected from NCS under dark conditions at 20 degrees C, while no significant emission was observed in other antitumor antibiotics, such as, ...
Lawrence J F - - 1986
Methodology was developed for the determination of eight polycyclic aromatic hydrocarbons (PAH) in five food categories including meat/fish, dried dairy products, cereals, leafy vegetables and vegetable/marine oils. The eight PAH were fluoranthene, benzo[a]anthracene, benzo[k]fluoranthene, benzo[b]fluoranthene, benzo[a]pyrene, 7,12-dimethylbenzo[a]anthracene, dibenzo[ah]anthracene and dibenzo[ai]pyrene. Samples were digested with alcoholic KOH followed by partitioning into ...
Phelps D K - - 1986
Hexachlorobenzene (HCB) has been designated by the US Environmental Protection Agency as a chemical of interest. Re-examination of previously analysed gas chromatograms and archived samples revealed peaks that co-eluted with the authentic HCB standard. Levels of HCB were less than 1 ng/g in all samples re-examined, and were at least ...
Waller R E - - 1985
The concentrations of smoke, polycyclic aromatic hydrocarbons (PAHs), and some gaseous air pollutants have been measured in two London Transport diesel bus garages and compared with observations made in the same garages over 20 years earlier. The main feature of the results was a large reduction in the background concentrations ...
Tannenbaum E - - 1985
Pyrolysis experiments were carried out on Monterey formation kerogen and bitumen and Green River formation kerogen (Type II and I, respectively), in the presence and absence of montmorillonite, illite and calcite at 200 and 300 degrees C for 2-2000 hours. The pyrolysis products were identified and quantified and the results ...
Häsänen E - - 1984
The concentrations of polycyclic aromatic hydrocarbons (PAH) in the air of three different types of wood-heated saunas were studied. The highest concentrations were found in the smoke sauna (total PAH 170-1550 micrograms/m3, benzo[a]pyrene 4.6-20 micrograms/m3) the second highest in the preheated sauna (total PAH 50-90 micrograms/m3, benzo[a]pyrene 3.4-4.5 micrograms/m3) and ...
Roberts N B - - 1984
Direct-current plasma emission spectrometry determines food calcium and phosphorus, faecal calcium and chromium, and urinary calcium and phosphorus accurately, precisely and rapidly without acid digestion or dry ashing. Food and faeces are homogenised, diluted and aspirated directly into the plasma. The method makes metabolic balances swifter and less labour-intensive; it ...
Dennis M J - - 1984
A method is described for the sample clean-up and estimation of nitropolycyclic aromatic hydrocarbons (nitro-PAH) in foods. The analysis involves the novel use of a coupled capillary gas chromatograph/thermal energy analyser and provides a detection limit for 1-nitropyrene of 12 pg (equivalent to 0.02 micrograms/kg for a 50-g sample). Only ...
Steinberger E H - - 1982
Ozone concentrations have been measured in Jerusalem since 1977 by a chemiluminescent ozone meter. During the last five years ozone levels have increased considerably. In order to test whether this increase reflected the growth in the number of motor vehicles or was caused by atmospheric conditions, the summer data of ...
Hoffer T E - - 1982
From 1969 through 1978 an extensive ambient air quality monitoring program, including the measurement of atmospheric concentrations of ozone, has been conducted in a remote section of the desert in the southwestern U.S. Using a Monitor Labs chemiluminescent ozone instrument, these levels were measured atop a small mountain 500 feet ...
Howard J W - - 1980
Various polycyclic aromatic hydrocarbons (PAH) some of which are carcinogenic have been demonstrated to be present in water, air, food soils, etc. and are now considered by experts to be ubiquitous in our environment. During the last decade significant progress has been made in the development of multiresidue methods for ...
Soós K - - 1980
The quantity of phycyclic aromatic hydrocarbons (PAHs) in Hungarian foods and consumer goods were measured in more than 300 samples of food and other consumables. In more than 60% of the samples, pyrene, fluoranthene, benz(a)anthracene and benzo(g.h.i)perylene were detectable besides the highly carcinogenic benzo(a)pyrene (BaP). Investigational results and consumption data ...
Fritz W - - 1980
Smoking is a well-known source of food contaminated caused by carcinogenic polycyclic aromatic hydrocarbons. Epidemiological studies indicates a statistical correlation between the increased occurrence of cancer of the intestinal tract and the frequent intake of smoked foods. As observed during the last 10 years in a certain district of Hungary ...
Joe F L FL - - 1979
The Food and Drug Administration multi-component regulatory procedure for determining polynuclear aromatic hydrocarbons in foods was recently used to survey 24 foodstuffs for the presence of these compounds. The procedure has a reliable limit of quantitation of 2 ppb. The potent carcinogen benzo(a)pyrene was detected in only one of the ...
Lu P Y - - 1977
Radiolabeled benzo-((alpha)-pyrene, benzidine, and vinyl chloride were evaluated in laboratory model ecosystems for environmental fate, degradation pathways, bioconcentration, and food chain accumulation. The comparative effects of microsomal detoxications were evaluated using the inhibitor piperonyl butoxide. The accumulation and bioconcentration of benzo-(alpha)-pyrene and benzidine were closely correlated with their octanol/water partition ...
Grimmer G - - 1977
1. On the basis of figures for the production of PAH during the Europa drive cycle by 100 passenger cars and those for the consumption of petrol in the Federal Republic of Germany, an annual emission of 1,850 kg benzo[a]pyrene from petrol engine vehicles has been calculated. 2. The carcinogenic ...
Canick J A - - 1976
When measured in vitro using human placental microsomal preparations, the aromatization of 16alpha-hydroxytestosterone to estriol and androstenedione to estrone and estradiol proceeds at almost identical initial rates. Important differences between 16alpha-hydroxytestosterone and adrostenedione aromatization are evident, however. While substantial findings have implicated cytochrome P-450 in placental aromatization, the aromatizaiton of ...
Stupfel M - - 1976
The influence of auto exhaust on man's health is difficult to gauge considering the intricacy of human environmental urban stresses and particularly of other air polluting (industrial, domestic) emissions. Epidemiological surveys made in road tunnel employees and in traffic officers have not demonstrated specific effects and have often been complicated ...
Shabad L M - - 1976
Spectrofluorescent methods of analysis have shown that soot and exhaust products of aviation engines, both piston and turbine, contain benzo[a]pyrene (BP). A modern aircraft engine releases into the atmosphere from 2-10 mg BP per min. Extracts of aviation engine soot applied to the skin of mice induced malignant tumors in ...
Huggins C - - 1969
Pulse doses of emulsions of ten polynuclear aromatic hydrocarbons were found to destroy the adrenal cortex selectively. The corticolytic hydrocarbons are derivatives of 12-methylbenz(a)anthracene which possess at position 7 an alkyl, methoxymethyl, formyl, or hydroxyalkyl group. It would appear that the active corticolytic agent is 7-hydroxyalkyl-12-methylbenz(a)anthracene, of chemical source or ...
LIJINSKY W - - 1964
The possible production of carcinogenic polynuclear hydrocarbons in the charcoal broiling of food has been investigated. Fifteen steaks were cooked and the polynuclear compounds were extracted, separated by chromatography, and identified spectrometrically. Many polynuclear hydrocarbons were identified, but no nitrogen heterocyclic compounds were detected. The carcinogen benzo(a)pyrene was present in ...
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