- Dettagli della rivista
- Formato
- Rivista
- eISSN
- 2719-9509
- Pubblicato per la prima volta
- 01 Jan 1992
- Periodo di pubblicazione
- 4 volte all'anno
- Lingue
- Inglese
Cerca
- Accesso libero
Systematic Studies on the Breakdown of p,p'-DDT in Tobacco Smokes
Pagine: 167 - 174
Astratto
These studies, on the pyrolysis of DDT, can be divided into two sections. Section 1 deals with the pyrolysis of p,p'-DDT in a nitrogen atmosphere at 900°C and subsequent isolation and identification of CH2Cl2, CHCl3, CCl4, CHCl = CCl2, CCl2 = CCl2, chlorobenzene, CCl3- CCl3, a,p-dichlorotoluene, p,p'-dichlorobiphenyl, bis-(p-chlorophenyl)methane, cis-p,p'-dichlorostilbene, bis-(p-chlorophenyI)chloromethane, p,p'-DDM, p,p'-DDE, trans-p,p'-dichlorostilbene, p,p'-TDE, and p,p'-DDT. Mechanisms for the formation of these compounds are proposed, and on that basis prediction is made on the formation of DDT degradation products when DDT-treated tobacco is smoked. Section 2 deals with pyrolytic degradation of DDT incorporated in tobacco. Methyl chloride, bis-(p-chlorophenyl)methane, p,p'-dichlorobenzophenone, p,p'-DDM, trans-p,p'-dichlorostilbene, p,p'-DDE, p,p'-TDE and p,p'-DDT were identified as the pyrolysis products. Based on the type and nature of pyrolysis products obtained, eight conclusions are made.
- Accesso libero
The Determination of Malathion Residues in Tobacco and Tobacco Smoke Condensate
Pagine: 175 - 178
Astratto
A method was developed to determine Malathion on tobacco and in smoke condensate at levels of 0.05 ppm and above. A study on the Malathion content of leaf tobacco, cigarette tobacco, and the transfer rate from cigarettes into the mainstream smoke was made. The analysis revealed that the air-cured tobacco contained 0.1 ppm of the pesticide, while the flue-cured samples and cigarettes contained less than 0.05 ppm. The transfer studies indicated that approximately 91-92 % of Malathion is lost during the smoking of cigarettes.
- Accesso libero
Organophosphorus and Carbamate Insecticides as Substitutes for DDT in Controlling the Tobacco Flea Beetle on Flue-Cured Tobacco
Pagine: 179 - 182
Astratto
Field experiments conducted in North Carolina during 1964-65 to compare the residual effectiveness of insecticidal sprays against the tobacco flea beetle, Epitrix hirtipennis (Melsheimer), on flue-cured tobacco showed that, for the number of days indicated after application, the following treatments provided control similar to that obtained with 1 lb / acre of DDT: [1] for 10 days, 0.5lb of carbofuran, Dasanit® (o,o-diethyl o-[p-(methylsulfinyl)phenyl]phosphorothioate), dimethoate, Gardona® (2-chloro-1-(2,4,5-trichlorophenyl) vinyl dimethyl phosphate), Imidan®(o,o-dimethyl S- phthalimidomethyl phosphorodithioate), and Supracide® (S-((2-methoxy-5oxo-Δ2-1,3,4-thiadiazolin-4-yl)methyl) o,o-dimethyl phosphorodithioate), and 1lb of aminocarb and MCA-600 (benzo[b]thien-4-yl methylcarbamate), [2] for 6 days, 0.25 lb of azinphosmethyl, 0.5 lb of dicrotophos and phosphamidon, and 1 lb of carbaryl, and [3] for 3 days, 0.25 lb of parathion and 1 lb of carbanolate. One-fourth lb of methyl parathion, 0.5lb of diazinon, endosulfan, malathion, and naled, and 1 lb of TDE provided control inferior to that of 1 lb of DDT for 3 days and no significant control thereafter. Variable control was obtained with monocrotophos
- Accesso libero
Chemical Studies on Tobacco Smoke: XI. Dibenzofurans in Cigarette Smoke
Pagine: 183 - 188
Astratto
A method was developed for the isolation of dibenzofuran (DBF) and its four methyl derivatives (MDBF) from cigarette smoke. Since an excess of alkanes was found to inhibit the column chromatographic separation of dibenzofurans, distribution systems had to be developed which, in the initial step of the analysis, would lead to an enrichment of DBF and MDBF with loss of the bulk of the tobacco smoke alkanes. The three distributions which lead to a preliminary concentration of these heterocyclics were the solvent pairs methanol/water (4:1) and n-hexane; n-hexane and dimethylformamide; and water/dimethylformamide (4:1) and n-hexane. The resulting tobacco ''tar" extract was chromatographed on deactivated alumina and subsequently on Sephadex LH-20. The final concentrate of DBF was separated into individual components by gas chromatography. With the aid of this method we separated from cigarette smoke dibenzofuran and 1-, 2-, 3- and 4-methyldibenzofurans. These five dibenzofurans were identified by the retention times in two gas chromatographic systems, ultra-violet absorption spectra, and mass spectral analysis. The final DBF concentrate from cigarette smoke also contains, as major components, acenaphthylene and fluorene. For the quantitative analysis we employed dibenzofuran-1,2,3,4,4a,9b-14C6 as internal standard. This labelled compound was synthesized by the Trippett method on a microscale from phenol and 2-bromocyclohexanone. The mainstream smoke of an 85 mm U.S. nonfilter cigarette contained 106 ng of dibenzofuran, 40 ng of 1-methyldibenzofuran, 100 ng of 2- and 3-methyldibenzofurans, and 52 ng of 4-methyldibenzofuran. The identification of DBF and its four methyl derivatives in cigarette smoke represents their first isolation from a respiratory environmet
- Accesso libero
Fate of Aflatoxins in Cigarette Tobacco
Pagine: 189 - 192
Astratto
Commercial non-filter cigarettes were treated with 100 µg or 300 µg of aflatoxin B1 and smoked in a smoking machine. The 25 mm butts, the particulate phase of smoke collected on Cambridge filters, the gaseous phase of smoke, and the ashes combined from 10 cigarettes in each experiment, were tested for the presence of aflatoxins by TLC and spectrophotofluorometry. In six separate smoking experiments no trace of aflatoxin B1 could be detected in any of the fractions examined. The crystalline aflatoxin B1 used in these experiments was prepared by growing cultures of Aspergillus flavus on rice. The acute oral LD50 (12 days) in weanling rats was 7.5 mg/kg and the acute oral LD50 (7 days) in one-to-three-day old white Pekin ducklings was 0.78 mg/kg ± 0.30 mg/kg. The melting point of aflatoxin B1 was 263-264°C, and the molar extinction coefficient (ε) was 25,000 and 13,400 at wave lengths of 361 mµ and 265 mµ, respectively. The fluorescence excitation and emission wave lengths were 363 mµ and 423 mµ, respectively
- Accesso libero
A Market Analysis on the Cigarette-Consumption in the Federal Republic of Germany During 1961-1969 - Einige Trendanalysen zum Problem des Cigarettenrauchens in der Bundesrepublik Deutschland für die Jahre 1961-1969
Pagine: 193 - 197
Astratto
On the basis of numerous research results and data on the development of condensate contents of German cigarettes, their share of the market, the smoked length of cigarettes in laboratory tests as opposed to the average smoker, the pro capita consumption of cigarettes in the Federal Republic of Germany and the trends of the smokers' share, an estimate has been prepared in the Federal Republic on the yearly pro capita consumption of smoke condensates covering the years 1961-1969. The value for 1961 amounts to 40.2 gr., whereas for the year 1969 31.9 gr. Have been obtained. This means that the consumption of cigarette condensates in the Federal Republic has decreased during the last years. At a nearly constant share of smokers it can be seen that the consumption of smoke condensates per smoker has decreased by about 20 % during the years between 1961 and 1969 despite an increased cigarette consumption
- Accesso libero
Examination of the Cigarette Butt Length in 1968 in the Federal Republic of Germany - Über die Länge von Cigarettenstummeln in der Bundesrepublik Deutschland im Jahre 1968
Pagine: 198 - 200
Astratto
The length of the butts left by the smokers was ascertained from approx. 40000 cigarette butts gathered in 1968 in the whole of the Federal Republic of Germany and West Berlin. In comparison with an examination made in 1959 it could be seen that the length of the butts is increasing. Thus the length of the butts of filter cigarettes increased by 8.5 mm (from 22.1 to 30.6 mm) and the length of the butts of cigarettes without filter by 6.3 mm (from 19.3 to 25.6 mm)