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1.

The present study has carried out with an objective of determining the activity concentrations of two radionuclides namely polonium-210 (210Po) and lead-210 (210Pb) in smoke tobacco products (cigarette, bidi and cigar) and smokeless tobacco products (chewing tobacco and snuff) consumed in Tiruchirappalli District, Tamil Nadu (India) and their annual committed effective dose to tobacco consumers. The concentration of 210Po was always higher than that of 210Pb in all the analyzed tobacco products. It also revealed that 79% of Annual committed effective dose comes from 210Po and about 21% from 210Pb. Maximum concentration (13.2 mBq g?1) of 210Po recorded in cigarette and lowest concentration was observed in snuff (6.4 mBq g?1). The highest mean committed effective dose of 210Po and 210Pb in various tobacco products were found in cigarette followed by bidi, cigar, chewing tobacco and snuff. The study revealed that the tobacco products available in Tiruchirappalli District contain a relatively lower concentration of radionuclides when compared to other regional studies. Since this kind of study in India is fragmentary, the present study has generated a base data for the first time for entire Tiruchirappalli District.

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2.
Various Syrian cigarettes /Hamra long filter, Oreidt, Granata, Palmyra, Hamra short filter/ were analyzed for their210Po content.210Po was precipitated on a silver plate after chemical separation and measured by -spectroscopy. The concentration values found for210Po ranged between 0.02 and 0.08 pCi g–1.  相似文献   

3.
210Pb and210Po in human hair have been measured to serve as an aid in order to estimate the dietary intake and body burden of these radionuclides of Japanese. The210Po concentrations found in 83 hair samples were ranging from 4.0 to 59.3 mBq/g with a mean (median) value of 18.2±12.2 (14.9) mBq/g as compared to the210Pb concentrations from 0.7 to 6.5 mBq/g with a mean (median) value of 2.3±1.1 (2.0) mBq/g. The210Po/210Pb activity ratios (mean: 8.7±5.1, median: 7.1) were surprisingly higher compared with the available literature value of about 2. The high concentration of210Po in human hair of Japanese may be due to the ingestion of animal protein mainly in the form of seafood.  相似文献   

4.
Levels of 210Po in blood, urine and hair of some Saudi smokers   总被引:1,自引:0,他引:1  
Summary The activity concentration of 210Po was investigated in blood, urine and hair samples of some non-smokers, cigarette-smokers (tobacco-smokers) and shisha smokers (jurak- and mehassel-smokers). The results indicated that 210Po concentration was variable within each group of volunteers and fluctuated within certain range. The activity concentration in the blood of the non-smokers, the cigarette-smokers and the shisha-smokers was found to be ranged from 7-77, 17-86 and 22-92 mBq/l, respectively. These values were ranged from 1.5-10, 3.3-15.9 and 2.2-19.6 mBq/l in the urine samples of the same volunteers, respectively. The 210Po activity concentration in their hair was found to be ranged from 1.9-4.8, 1.9-6.4 and 2-6.5 Bq/kg, respectively. The obtained results are discussed and some conclusions, based upon the average values, were drawn.  相似文献   

5.
A highly selective method is described for the determination of 239,240Pu and 238Pu in soils by extraction chromatography with Microthene-710/tri-n-octylamine. The method is especially suitable for volcanic soils containing high concentrations of natural alpha radionuclides (Th, Po, U, etc.). The detection limit by α-spectrometry is 2.2 mBq kg?1 for 50-g soil samples. The average chemical yield, obtained by adding 242Pu as the internal standard, is 69.5 ± 17.1%. An IAEA reference soil was analyzed, with a relative error of 6.7% for 239Pu. The concentration of 2239,240Pu in thirteen analyzed soils and sediments ranged from 26.6 to 429 mBq kg?1.  相似文献   

6.
The concentrations of 226Ra, 210Po and 210Pb have been measured, by high efficiency 5″ × 5″ NaI(Tl) gamma ray spectrometer and chemical deposition method, in surface water samples from major rivers Kali, Sharavathi and Netravathi of coastal Karnataka. Measurements of 226Ra, 210Po and 210Pb in surface water from these rivers are important because the river water is main source of potable water in this region due to inadequate supply of treated water. The mean activity of 226Ra, 210Po and 210Pb in the surface water of the river Kali was found to be 5.13 mBq L−1, 1.28 and 1.37 Bq L−1, for Sharavathi River the mean activity was found to be 3.37 mBq L−1, 1.30 and 1.44 Bq L−1. In Netravathi River the mean activity of 226Ra, 210Po and 210Pb was found to be 3.30 mBq L−1, 1.00 and 1.20 Bq L−1. From the measured concentration of 226Ra, 210Po and 210Pb, the Effective dose to the population of the region was computed. The results of these systematic studies are presented and discussed in the paper.  相似文献   

7.
The paper presents systematic studies on the vertical profiles of 210Po, an important decay product of 238U, in soils along coastal Kerala. Soil samples collected from different depth intervals 0–10, 10–20, 20–30 cm were analyzed for 210Po activity concentration by radiochemical methods. The activity 210Po in soil samples were counted using a ZnS(Ag) alpha scintillation counting system. The mean values of activity concentrations of 210Po in soil of various depths were found to be 8.66, 5.63 and 4.95 Bq kg−1 for depth intervals of 0–10, 10–20 and 20–30 cm, respectively. The overall activity concentration of 210Po in soil was found to vary from 2.26 ± 0.19 to 14.02 ± 0.12 Bq kg−1 with a mean value of 6.43 Bq kg−1. Maximum activity concentration was found in soil samples of Kollam region with the mean value of 10.08 ± 0.92 Bq kg−1. The activity of 210Po was found to be comparatively high in surface soil. The variation of 210Po activity concentration with organic matter contents was studied. 210Polonium activity concentration was found to increase with increasing organic matter content.  相似文献   

8.
The concentration of two important radionuclides: 210Pb and its decay product 210Po in the urban air in the center of the Polish city of Lodz were measured during the winter and spring seasons of 2008–2009. Urban airborne particulate matter was collected using two methods: an Anderson 9-stage impactor, and a high-volume aerosol sampler type ASS500 working in the frames of the aerosol sampling network in Poland, established for radionuclide monitoring. Average concentrations for 10 months sampling period for 210Pb and 210Po were 0.556 and 0.067 mBq/m3, respectively. However remarkable fluctuations due to meteorological condition were observed: from 0.010 to 0.431 mBq/m3 for 210Po and from 0.167 to 1.847 mBq/m3 for 210Pb. The highest concentrations, almost 60% of the total activities, of both radionuclides were found in the first two fine aerosol fractions with particle diameters below 0.36 μm. The aerosol residence times calculated from the 210Po/210Pb ratio ranged from 7 to 120 days.  相似文献   

9.
210Po is absorbed into the human body by seafood intake. Especially, mollusks and mussels are known to have much higher 210Po concentration than fish among various other types of seafood and are consumed in large quantities in Aegean Sea. 210Po and 210Pb radionuclide concentrations are obtained in the Mediterranean mussel (Mytilus galloprovincialis) and in the sediment samples collected from the Çanakkale. The activity concentrations of 210Po and 210Pb are counted using alpha spectrometry. Activity concentrations of 210Po and 210Pb in mussels are in the ranged of 227 ± 11–540 ± 38 and 17 ± 4–48 ± 5 Bq kg?1 dw (dry weight), for sediments the ranges are 23 ± 6–41 ± 3 and 15 ± 3–44 ± 1 Bq kg?1 dw, respectively. Additionally, annual committed effective dose are calculated due to consumption mussel in Çanakkale coastal region. The highest effective doses of 210Po and 210Po are found as 3187 and 56 μSv, respectively. Finally, risk analysis assessment is recommended to determine the pollutant effects of radionuclides. The risk fractions at the concentrations are easily determined with this evaluation process. This methodology has made a great contribution to risk assessments.  相似文献   

10.
Polonium-210 has been measured in the soft parts of Anadara granosa purchased at Kuala Selangor, West Coast of Malaysia in August 2001, April 2002 and September 2002. It is shown that 210Po is non-uniformly distributed within cockles of various sizes (i.e., 2.5, 3.0, 3.5 and 4.0 cm of shell length) and the concentration of 210Po in the soft parts of cockle was significantly different (p<0.05) due to sampling date. The highest value was observed in the smallest cockle with a shell length of 2.5 cm (411.6±26.16 Bq/g dry wt.). It is clear that there is an allometric relationship between 210Po activity concentration and individual cockle weight. This may reflect on the differences of metabolic rate and growth age of cockles. The mean activity concentration of 210Po measured in Kuala Selangor filtered water were 1.75±0.17, 0.79±0.08 and 1.13±0.20 Bq/kg for August 2001, April 2002 and September 2002, respectively. The yield concentration factors for 210Po in the soft parts of cockles varies from 27.3. 103 to 106.9. 103. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

11.
The paper deals with the determination of 210 Pb and 210 Po in mineral and biological environmental samples. 210 Pb and 210 Po were preconcentrated from filtered water samples by coprecipitation with iron(III) hydroxide at pH 9-10 using ammonia solution and the precipitate was dissolved with HCl and mineralized with H2O2. 210 Pb and 210 Po in soil or sediment, algae and mussel samples were sequentially leached out at 250 °C with HNO3 +HF, HClO4 and HCl. About 10-20% of the leaching solution was used for 210 Po determination which was carried out at 85-90 °C for 4 hours by suspending a silver disk in a HCl solution of pH 1.5 and containing some hydroxylamine hydrochloride and sodium citrate. No preliminary separation was required and essentially quantitative recoveries were obtained by using standard 209 Po tracer. The remains of the leaching solution were used for the determination of 210 Pb which was first separated by a BIO-RAD-AG 1-X4 resin column, then purified by using Na2S to precipitate as PbS and finally precipitated as PbSO4 for source preparation. Starting from 3 g sediment (30 liter water), the lower limits of detection of the method were 0.73 Bq.kg-1 (0.078 mBq.l-1 ) for 210 Pb and 0.25 Bq.kg-1 (0.016 mBq.l-1 ) for 210 Po. The procedure has been checked with two certified samples supplied by the International Atomic Energy Agency (IAEA) and reliable results were obtained. Most of the analyzed samples were sediments, showing average yields of 84.2±5.2% for 210 Pb and 96.4±4.1% for 210 Po.  相似文献   

12.
In order to evaluate the possible radiological impact to the local public and environment from a phosphogypsum stockpile, 210Po and 210Pb concentrations in river water, lagoon water, suspended matter, superficial sediment, algae and bivalves samples collected in Venice lagoon area have been investigated. The results show that the mean 210Po and 210Pb concentrations in river water are 1.42±0.36 mBq.l-1 and 1.46±0.39 mBq.l-1 with a mean 210Po/210Pb ratio of 0.98±0.17 and about 60% of them are associated with the particulate; 210Po and 210Pb contribution from the phosphogypsum stockpile to the river water is negligible. Higher 210Po (2.61-5.67 mBq.l-1) and 210Pb (1.31-3.62 mBq.l-1) concentrations in the lagoon waters have been observed if compared with the literature values. About 60% of 210Po and 210Pb are found in the soluble form with a mean 210Po/210Pb ratio of 1.79±1.47. 210Po and 210Pb concentrations in 28 out 37 sediment samples ranged from 26 to 45 Bq.kg-1 (dry weight), only 9 sediments with 210Po and 210Pb concentrations greater than 45 Bq.kg-1 are found and most of them are located 1-4 km near the phosphogypsum stockpile. The elevated 210Po and 210Pb concentrations in the sediments may be due to the contamination from the phosphogypsum stockpile. The mean 210Po/210Pb ratio (0.986±0.049) in the sediments shows that 210Po and 210Pb exist in nearly secular equilibrium. 210Po and 210Pb concentrations in algae vary with different species. The mean 210Po and 210Pb concentrations in Gracilaria compress and Ulva laetevirens which show a similar behavior, are 3.18±1.23 Bq.kg-1 and 2.42±1.26 Bq.kg-1 (fresh weight), respectively, with a mean 210Po/210Pb ratio of 1.45±0.34. The mean concentration factors with respect to the filtered water are 1096±424 for 210Po and 1299±680 for 210Pb. The mean 210Po and 210Pb concentrations in the soft part of Mytilus edulis are 23.2±9.7 Bq.kg-1 and 0.537±0.203 Bq.kg-1 (fresh weight), respectively, with a mean 210Po/210Pb ratio of 43.6±10.0. The mean concentration factors with respect to the filtered water are 8006±3351 for 210Po and 290±109 for 210Pb, showing a very high accumulation effect for 210Po. The accumulation behaviors of Cerastoderma glaucum and Tapes philippinarum for 210Po are similar to Mytilus edulis, but that for 210Pb seems less effective, corresponding to a relatively higher 210Po/210Pb ratio. The estimated committed effective doses from 210Po for the individual local public through ingestion of bivalves are in the range of 0.050-0.231 mSv.y-1.  相似文献   

13.
The determination of 210Po in phosphoric acid reagent by alpha-ray spectrometry using extraction chromatographic resin is presented. The decontamination factors of interference elements were measured. It was observed that HCl, HNO3, ascorbic acid, thioacetamide and Cu were free from 210Po but Pb contain small amounts of 210Po. 210Po in phosphoric acid samples was ranged from <8 to 2.4 Bq/l. The detection limit of 210Po in 50 ml of phosphoric acid is 8 mBq/l with a counting time of 1 day undercounting efficiency of 30%.  相似文献   

14.
This research was dedicated to the study of the background levels of 210Po and natural gamma emitters as 40K, 214Pb, 214Bi, 228Ac, 212Pb and 212Bi in coffee powder and in coffee beverage; also the artificial 137Cs was determined. In the coffee powder the mean 210Po activity resulted 7.25 ± 2.25 × 10?2 Bq kg?1. 40K showed a mean activity of 907.4 ± 115.6 Bq kg?1. The mean activity concentration of 214Pb and 214Bi, indicators of 226Ra, given as mean value of the two radionuclides, resulted 10.61 ± 4.02 Bq kg?1. 228Ac, 228Ra indicator, showed a mean activity concentration of 13.73 ± 3.20 Bq kg?1. The mean activity concentration of 212Pb, 224Ra indicator, was 8.28 ± 2.88 Bq kg?1. 208Tl, 224Ra indicator, presented a mean activity concentration of 11.03 ± 4.34 Bq kg?1. In all samples, the artifical 137Cs resulted below the detection limit (2.0 Bq kg?1). The arithmetical mean value of percentage of 210Po extraction in coffee beverage resulted 20.5 ± 6.9. The percentage of transfer of gamma emitters,40K, 214Pb, 214Bi, 228Ac, 212Pb, 208Tl resulted of 80.0, 33.5, 24.7, 30.0, 35.1 and 53.5 % for 40K, 214Pb, 214Bi, 228Ac, 212Pb and 208Tl respectively.  相似文献   

15.
Our previous studies indicated the suitability of tobacco plants for biomonitoring remediated depositories, due to their 210Po and 210Pb accumulation ability. The methods and requirements of testing 210Pb uptake by leaf-surface adsorption was investigated and implemented in the construction of a controlled environment. Uranium ore (theoretical Rn concentration 638 Bqm?3) was the main source of radon and progeny. Rn concentrations were measured by RAD7, AlphaGUARD, EQF 3220, RTM 2100 and CR-39 SSNTDs (411–516 Bqm?3). Activity concentrations of the attached and unattached fractions were determined by EQF 3220. The results are indicative of good measurement setup for tracking 210Po(Pb) uptake pathways.  相似文献   

16.
The aim of this study was the determination one of the most radiotoxic elements, 210Po in different parts of tobacco plant from Poland. Investigation revealed that polonium is non-uniformly distributed within tobacco plant. Tobacco leaves constituting about 50% of the wet mass, contain 87.1% of the total burden of 210Po. Among the analyzed leaves about 66% of polonium is located in the oldest, over-ground part. The data obtained here indicate that 210Po is generally taken up by tobacco from the dry or wet deposition of the radioactive fall-out onto the plant. Moreover, 210Po concentration in tobacco leaves from Poland are higher than that in the other countries.  相似文献   

17.
Polonium-210 distribution in Syrian phosphogypsum   总被引:1,自引:0,他引:1  
Polonium-210 distributions in Syrian phosphogypsum and its leaching mechanisms have been evaluated. Radiochemical analyses have shown that 210Po concentration in Syrian phosphogypsum is always higher than 226Ra concentration. 210Po concentrations were found to vary between 373 and 589 Bq.kg–1 with an average value of 471 Bq.kg–1, which is lower than values reported in other countries. 210Po was found to be more concentrated in smaller particles; a specific activity of 827 Bq.kg–1 in particles less than 250 mesh was observed. Leaching experiments using distilled water have shown that 210Po are strongly bounded to phosphogypsum particles. The amount of 210Po transferred to aqueous media does not exceed 5.6% and 8.4% for batch wise and continuous leaching, respectively; lowering the pH has increased this percentage to 20%. In addition, leaching with diluted sulfuric acid indicated that 80% of polonium is present as water insoluble quadrivalent polonium sulfate while 20% as soluble simple polonium sulfate. However, the obtained data could be used to explain environmental pathways of 210Po from phosphogypsum.  相似文献   

18.
Nicotine was selected as the target molecule for monitoring of the smoking process by multicommutation Fourier Transform Infrared spectroscopy (FTIR). The method involved the use of CHCl3 for on-line extraction of nicotine from tobacco, cigarette filters and tobacco ash from NH4OH alkalinized samples, and absorbance measurement of the characteristic band at 1316 cm−1 in the stopped-flow mode, by obtaining the peak area in the range between 1334 and 1300 cm−1. Under the best operational conditions, the procedure developed provided a detection limit of 0.05 mg mL−1 nicotine, corresponding to 0.5 mg g−1 in the solid sample, a relative standard deviation less than 2.5%, and a sampling frequency of 12 determinations h−1. It can be concluded that nicotine migrates in the smoke mainstream towards the filter during the smoking process. The smoking of cigarettes and cigars is different. Nicotine is retained weakly by both tobacco and filter in the case of cigarettes, and strongly by the unburned tobacco in cigars. The incomplete smoking of cigars and cigarettes reduces nicotine intake and thus reduces the additive effect.  相似文献   

19.
A sensitive and reliable metbod for the sequential separation and determination of plutonium,241Am and90Sr in soil samples was developed. Plutonium was separated by a Microthene-TNOA column. Then90Y (for90Sr determination) was separated from americium by a HDEHP column after elimination of large amounts of interfering stable or radioactive nuclides (iron,210Bi and210Po etc.) by an oxalate precipitation and a Microthene-TNOA column. Finally americium was purified by another HDEHP column and a PMBP-TOPO extraction. A special attention was paid to the decontamination of Pu and Am from210Po and of90Y from210Bi; the relevant decontamination factors resulted greater than 105, 106 and 104 respectively. The detection limits were 1.2 mBq/kg for Pu and 1.7 mBq/kg for241Am and 0.32 Bq/kg for90Sr. The procedure was checked by analyzing three certified samples supplied by IAEA. Some Italian soil samples were also analyzed giving average yields of 84.9±7.2% for Pu, 57.8±3.2%for Am and 96.7±1.6% for Y; the239+240Pu,238Pu,241Am and90Sr contents (Bq/kg) ranged from 0.347 to 1.53, from 0.013 to 0.048, from 0.126 to 0.556 and from 2.89 to 11.6 respectively and the average ratios were 0.037±0.017 for238Pu/239+240Pu, 0.357±0.040 for241Am/239+240Pu and 7.0±1.2 for90Sr/239+240Pu.  相似文献   

20.
It was found that heating of diluted nitric or hydrochloric acids in many years stored glass beakers can result in mBq quantities of 210Po leached from beaker walls to the solution. In the case of freshly bought beakers acid leaching of 210Po was not observed. We suppose that acid leachable 210Po in old beakers is mainly due to implantation of radon progenies (from air) into superficial layers of glass beaker walls.  相似文献   

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