Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Gasoline”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

[Forecasting octane numbers of gasoline by NIR spectroscopy and the manufacture of octane number analyzer].

The predictive model of octane numbers, of gasoline was developed by using MLR and PLS method of chemometrics. It is applicable to forecast the MON, RON and PON of gasoline of catalytic cracking, catalytic reforming, alkylating as well as blended products. A near infrared optical multichannel analyzer (NIR-OMA) and a software package of octane number were developed. Combining both mentioned above a NIR-OM octane number analyzer was developed. With this NIR-OMONA one can obtain the MON, RON and PON (antiknock index) data in less than 1/2 minute with an accuracy of 0.6 ON unit and a precision of 0.1 ON unit by using 3-15 mL gasoline sample.

English Abstract↗

Manganese in the U.S. gasoline supply.

Methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic manganese compound recently approved for use in the United States as a gasoline additive. MMT use is expected to increase. This Commentary analyzes the impact of MMT use on population exposure to manganese, the health effects associated with manganese exposure, and the possibility that MMT use will lead to toxicity in the population. Although MMT use would result in only a small increment in most people's manganese exposure, certain populations will be disproportionately exposed. Although manganese is an essential nutrient at low levels, high-level manganese exposure leads to a characteristic severe nervous system toxicity. Pulmonary toxicity also occurs at high levels of exposure, and developmental toxicity to fetuses is an important concern based on more limited data. Selected subpopulations may be especially susceptible to the toxic effects of manganese. The critical question is whether the additional population exposure to manganese that would result from widespread MMT use would lead to toxic effects. Currently available evidence does not permit firm conclusions. Common sense and prudence therefore dictate that MMT not be used until further data are available and its safety is confirmed. Several measures are recommended to address the impending use of MMT in the U.S. gasoline supply.

Animals↗

Clamped in a straitjacket: the insertion of lead into gasoline.

In 1925, shortly after production of tetraethyl lead began, an outbreak of psychosis occurred in all three operating plants, and a number of workers died in acute mania. A temporary moratorium on the production of tetraethyl lead was imposed, and the Public Health Service convened a meeting of scientists, public health officials, and industrial representatives to investigate the safety of the product. This paper reviews the steps leading to the insertion of lead into gasoline, the response of industry to the tragic poisoning, the actions of the public health authorities to investigate the episode, and the forces that resulted in the restoration of the additive to gasoline.

Chemical Industry↗

The removal of lead from gasoline: historical and personal reflections.

Tetraethyllead (TEL) was first fabricated for use in gasoline in 1923. Shortly after manufacture began, workers at all three plants began to become floridly psychotic and die. A moratorium on TEL production was put into place, but was lifted in 1926. Between 1926 and 1965, the prevailing consensus was that lead toxicity occurred only at high levels of exposure and that lead in the atmosphere was harmless. Most of the data on lead toxicity issued from a single source, the Kettering Laboratory in Cincinnati. In 1959, the first warnings of adverse health effects of lead at silent doses were raised by Clair Patterson, a geochemist. In hearings before the Senate Committee on Public Works, Senator Edward Muskie raised the question of adverse health effects from airborne lead. As new data accumulated on health effects of lead at lower doses, the movement to remove lead from gasoline gained momentum, and the Environmental Protection Agency examined the question. The removal of lead would take place over the next 25 years, and its accomplishment would require a severe change in the federal stance regarding its hazard. This article details the interaction of various forces, industrial, regulatory, judicial, public health, and public interest, that were engaged in this contest and estimates the value of this step.

Air Pollutants↗

Hepatic metabolism of heme in rats after exposure to benzene, gasoline and kerosene.

delta-Aminolevulinic acid (ALA) synthetase, delta-ALA dehydratase and heme oxygenase activities were studied in the liver of albino rats, 3 and 20 h after i.p. administration of benzene, gasoline, and kerosene. delta-ALA synthetase activity was increased markedly after benzene administration, while gasoline and kerosene treated groups showed decreased enzyme activity. Inhibition of delta-ALA dehydratase activity was observed in all three groups, but heme oxygenase activity was unchanged.

5-Aminolevulinate Synthetase↗

[Trichlorethylene-, carbon tetrachloride- and gasoline-intoxication in connection with arterio- and coronary sclerosis (author's transl)].

On the occasion of autopsies of 4 toxicomaniac adolescents sniffing and occasionally drinking trichlorethylene, carbon tetrachloride and gasoline severe arteriosclerotic damage of the coronary vessels was encountered. Experimental intoxication of 12 rabbits with these solvents over a period of 10 weeks, each time until a prenarcotic stage, provoked pathological changes in accordance with well known findings but no arteriosclerosis. Ergometrical examination with simultaneous recording of the E.C.G. of 6 adolescents with solvent-sniffing history and of 1 man, working for years under trichlorethylene exposure conditions and showing symptoms of chronic intoxication, revealed no signs of coronary-artery insufficiency. These findings are not inconsistent with the assumption -- though not substantiating it -- of a causal relationship between the intoxication with trichlorethylene, carbon terachloride and gasoline and the development of arteriosclerosis, as the coronary sclerosis may be of the elstic type with a very high degree of adaptability and the probands proved unable to reach the limit of maximum stress. In addition to the main purpose the occurrence of epileptic seizures following chronic trichlorethylene sniffing in one case and the manifestation of pulmonary obstruction following i.v. application of Methyl-Phenidat (Ritalin) in two cases are reported.

Adolescent↗

Alteration of rat liver microsomal monooxygenase activities by gasoline treatment.

Previous work has shown an increase in rat liver enzyme activities after chronic exposure to gasoline vapor. In the present study, male Sprague-Dawley rats were pretreated with unleaded gasoline at 1 and 5 ml/kg, i.p., and selected hepatic microsomal monooxygenase activities were determined at 18, 48, and 72 h. At 18 h, moderate increases were observed in P450 content (1.3-fold), cytochrome c-reductase activity (1.25-fold), and in N-nitrosodimethylamine demethylation rate (1.25- to 1.6-fold). Pentoxyresorufin dealkylase activity (an activity displayed primarily by P450IIB1) was significantly elevated at 18 and 48 h (30- to 60-fold), and ethoxyresorufin dealkylase activity (an activity displayed by P450 IA1) was elevated (2- to 4-fold). Immunoblot analysis revealed no change in P450IIE1 at these time points, but an elevation in P450IIB1 in agreement with the pentoxyresorufin dealkylase activity measurements.

Animals↗

Treatment of groundwater contaminated with PAHs, gasoline hydrocarbons, and methyl tert-butyl ether in a laboratory biomass-retaining bioreactor.

In this study, we investigated the treatability of co-mingled groundwater contaminated with polycyclic aromatic hydrocarbons (PAHs), gasoline hydrocarbons, and methyl tert-butyl ether (MtBE) using an ex-situ aerobic biotreatment system. The PAHs of interest were naphthalene, methyl-naphthalene, acenaphthene, acenaphthylene, and carbazole. The gasoline hydrocarbons included benzene, toluene, ethyl benzene, and p-xylene (BTEX). Two porous pot reactors were operated for a period of 10 months under the same influent contaminant concentrations. The contaminated groundwater was introduced into the reactors at a flow rate of 4 and 9 l/day, resulting in a hydraulic retention time (HRT) of 32 and 15 h, respectively. In both reactors, high removal efficiencies were achieved for the PAHs (>99%), BTEX and MtBE (>99.7%). All the PAHs of interest and the four BTEX compounds were detected at concentrations less than 1 mug/l throughout the study duration. Effluent MtBE from both reactors was observed at higher levels; nevertheless, its concentration was lower than the 5 mug/l Drinking Water Advisory for MtBE implemented in California.

Aerobiosis↗

Anaerobic biodegradation of natural gas condensate can be stimulated by the addition of gasoline.

Biodegradation of a broad range of linear and branched alkanes, parent and alkyl alicyclic hydrocarbons, and benzene and alkyl-substituted benzenes was observed when sediment and groundwater samples collected from a gas condensate-contaminated aquifer were incubated under methanogenic and especially under sulfate-reducing conditions, even though no exogenous nitrogen or phosphorus was added. This finding expands the range of hydrocarbon molecules known to undergo anaerobic decay and confirms that natural attenuation is an important process at this site. The addition of 1 mul of gasoline to the samples (approximately 10 ppm) had minimal impact on the biodegradation of saturated compounds, but substantially increased the diversity and extent of aromatic compounds undergoing transformation. We attribute this to the promotion or induction of biodegradation pathways in the indigenous microflora following the addition of the gasoline components. The promoting compounds are not precisely known, but may have been present in the initial condensate and reduced in concentration by various mechanisms (dissolution, biodegradation, etc.) such that their concentration in the aquifer fell below necessary levels. A variety of aromatic hydrocarbons would appear to be likely candidates.

Anaerobiosis↗

Field examination of ground water quality as an indicator of microbiological activity at gasoline contaminated sites.

Various portable electrodes and an on-line colorimetric test kit were used in the field to examine ground water quality as an indicator of natural bioremediation across two sites in Connecticut having subsurface gasoline contamination. The parameters examined included dissolved oxygen, dissolved carbon dioxide, direct redox potential (Eh), nitrate, ammonia and pH. These parameters permitted delineating regions of aerobic and anaerobic microbiological activity. Variations in these parameters over an eighteen month period along with gas chromatographic analyses of certain gasoline components in the ground water indicated that in-situ bioremediation was effective at containing the petroleum contamination at both sites. It was found that a new on-line colorimetric test kit for the determination of oxygen was more accurate than a commonly used dissolved oxygen electrode.

Ammonia↗

Use of leaded gasoline and volatile halogenated hydrocarbon emission from automotive exhaust.

The presence of volatile halogenated hydrocarbons (VHH) in the atmosphere of the urban areas of Piedmont and its possible correlation with traffic has been studied. Automotive exhausts of leaded and unleaded gasoline were tested, according to the "European Cycle" of the EEC guidlines N.C. 181/89, 7/9/1982, for the presence of seven VHH. The results show that VHH are produced in concentrations roughly proportional to the number of kilometres covered by each car. Cars filled with unleaded gasoline were substantially free of VHH. Thus, some of the VHH found in the atmosphere may arise from automotive (leaded petrol) exhausts.

Air Pollutants↗

An overview of atmospheric pollution in Italy before the use of new gasoline.

In 1991 an Italian law will impose a lead reduction in gasoline from 0.4 to 0 g/l. In the present paper we show the actual level (1988) of contamination in Turin city air, in relationship to: lead, some Volatile Halogenated Hydrocarbon and carbonyls that are also bound (directly or indirectly) to emissions from automobiles filled with leaded gasoline. The results confirm the presence in atmosphere of some important "risk factors" for public health that could be substituted with some other ones.

Air Pollution↗

Impact of reduction of lead in gasoline on the blood and hair lead levels in the population of Tarragona Province, Spain, 1990-1995.

The limitation in the use of lead in Spanish gasoline has induced a resulting decrease in atmospheric lead concentrations, a remarkable reduction in the lead levels of edible vegetables, as well as a marked decrease in the dietary lead intake of the population of Tarragona Province (Catalonia, N.E. Spain). The present study evaluates the impact of such decreases on blood lead values and hair lead concentrations in an adult and children population of that region. A total of 250 adult participants between 16-65 years of age and 252 children were included in the study. Blood and hair samples were subjected to lead analyses by graphite furnace atomic absorption spectrophotometry and inductively coupled plasma spectrometry, respectively. A substantial decline in both, blood lead levels in adults (47.5%) and lead concentrations in children's hair (53%) was observed. During the period 1990-1995, blood levels were reduced from 12.0 micrograms dl-1 to 6.3 micrograms dl-1, while the hair lead concentrations decreased from 8.8 micrograms g-1 to 4.1 micrograms g-1. These decreases were noted for all the subgroups (sex, age and place of residence) examined, and were mainly attributable to the reduced leaded gasoline consumption.

Adolescent↗

Post-mortem test for low-boiling arson residues of gasoline by gas chromatography-ion-trap mass spectrometry.

Using headspace capillary GC-MS with ion-trap detection, the additive in motor gasoline, MTBE (methyl tert.-butyl ether), was spotted in the blood from five victims of arsons set off with motor gasoline. In the brain from a death of a fire started by ignited isoparaffins, a number of branched C8 alkanes were found. Since 80 control samples of accidental fires, started by non-chemical means, tested negative for MTBE or isoparaffins, the data suggested that post-mortem exams for low-boiling organics may offer a new concept for arson analysis.

Ethers↗

Occurrence of PCDD/Fs in urban air before and after the ban of leaded gasoline.

The source of PCDDs and PCDFs in automotive exhaust is not yet fully explained. The chlorinated hydrocarbons used in the formulation of lead-alkyl additives were suspected as a possible major source. Based on this, the decreasing use of leaded gasoline followed by its final ban (occurred on 1/1/2002, in Italy) should have resulted in a decreasing presence of PCDD/Fs in urban air and possibly some differences in their profile. To investigate these aspects, we monitored PCDD/Fs for one year starting in September 2001, at a medium-traffic road site in Rome, with weekly frequency. Results were then compared with those obtained in a previous study performed before the ban (from February 2000 to January 2001) at the same site. As compared with the previous study, the yearly-averaged overall PCDD/F concentration, as toxic equivalent of 2,3,7,8-TCDD, decreased from 60 to 50 fg m(-3) I-TEQ; it remained unchanged, however, if one sample with a particularly high PCDD/F content was excluded from each data set. The monthly trend confirmed the one found in the former study. On an annual basis, the two mean congener profiles were almost identical. The concentration levels and the constancy of profiles, as calculated for the two periods, do not support the hypothesis of a major role of leaded gasoline, substantially different from unleaded one, in contributing to PCDD/F air pollution.

Air Pollutants, Occupational↗

Treatment of gasoline-contaminated waters by advanced oxidation processes.

In this study, the efficiency of advanced oxidative processes (AOPs) was investigated toward the degradation of aqueous solutions containing benzene, toluene and xylenes (BTX) and gasoline-contaminated waters. The results indicated that BTX can be effectively oxidized by near UV-assisted photo-Fenton process. The treatment permits almost total degradation of BTX and removal of more than 80% of the phenolic intermediates at reaction times of about 30 min. Preliminary investigations using water contaminated by gasoline suggest a good potentiality of the process for the treatment of large volumes of aqueous samples containing these polluting species. Heterogeneous photocatalysis and H2O2/UV system show lower degradation efficiency, probably due to the heterogeneous character of the TiO2-mediated system and lost of photonic efficiency of the H2O2/UV system in the presence of highly colored intermediated.

Benzene↗

Comparison of exposure assessment methods in occupational exposure to benzene in gasoline filling-station attendants.

The aim of this study was to assess gasoline filling-station attendants' exposure to benzene and to determine which biological exposure index (BEI), trans,trans-muconic acid (t,t-MA) or S-phenylmercapturic acid (S-PMA), shows better correlation with environmental exposure. Exposure to benzene was measured using passive samplers (Radiello) attached to the collar of the overalls of subjects (n=33) just before the work-shift (approximately 8h); analysis was performed by GC-FID. S-PMA and t,t-MA were determined, respectively, by an immunochemiluminescent assay based on specific monoclonal antibodies and by HPLC-UV at 264 nm. Both methods of biological monitoring were performed on beginning and end-shift urine samples, and expected t,t-MA and S-PMA values were calculated. Smoking habits and life-style were ascertained by means of a questionnaire. Both environmental and biological monitoring data showed that benzene exposure for gasoline filling-station attendants was low when compared with the respective ACGIH limit values (means-benzene: 0.044 mg/m(3); t,t-MA: 171 microg/g creatinine; S-PMA: 2.7 microg/g creatinine). No significant correlation was found between exposure to benzene and t,t-MA or S-PMA excretion data. The use of expected values was also experimented for S-PMA and t,t-MA. This consists of calculating, on the basis of the known half-life of the benzene metabolite, the concentration of that metabolite that a worker should present at the end of the work-shift, the difference between this value and the value actually found is a measure of benzene exposure during work. The use of expected values in biological monitoring did not improve correlations. At these low benzene levels, environmental monitoring seems to be the best method of evaluating individual exposure. However, biological monitoring remains useful, as a mean of assessing group exposure.

Acetylcysteine↗