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At least 19 recordsLinked to original sources
PubMed1999

[The basis for radioiodine therapy in differentiated thyroid cancer].

Radioiodine therapy of differentiated thyroid cancer is based on the ability of these tumors to accumulate iodine, making them accessible to a metabolic treatment with I-131, a beta-emitting radioisotope leading to in intensive, highly selective and tumoricidal irradiation of such cells. Radioiodine ablation of thyroid remnants is performed few weeks after radical thyroid surgery and significantly decreases the risk of recurrence of thyroid cancer and the risk of death due to thyroid cancer. Even in recurrent or metastatic thyroid cancer, radioiodine treatment will often be curative or at least result in long term improvement, making differentiated thyroid cancers among the most curable cancers at present. In Switzerland, radioiodine treatment of thyroid cancer must be done in specialized nuclear medicine wards. Secondary effects are mild and mostly related to the symptoms of hypothyroidism. Recurrent or metastatic thyroid cancer often necessitates an interdisciplinary approach, including surgery, radioiodine therapy and sometimes external radiation therapy. Follow-up should be done in specialized centers in collaboration with the patient's family doctor.

Adenocarcinoma, Follicular↗
PubMed2006

Inventories of fallout 210Pb and 137Cs radionuclides in moorland and woodland soils around Edinburgh urban area (UK).

Inventories of fallout (210)Pb and (137)Cs have been measured in moorland and woodland soils around the Edinburgh urban area, using a high purity germanium detector. The (210)Pb inventories in moorland soils were relatively uniform, with a mean value of 2520+/-270Bqm(-2). The mean (137)Cs inventory in moorland soils varied greatly from 1310 to 2100Bqm(-2), with a mean value of 1580+/-310Bqm(-2). The variability was ascribed mainly to the non-uniform distribution of fallout Chernobyl (137)Cs. The mean (210)Pb and (137)Cs inventories in woodland canopy soils were found to be 3630+/-380Bqm(-2) and 2510+/-510Bqm(-2), respectively. At sites for which both moorland and woodland data were available, the mean inventories provided fairly similar average enhancements of (47+/-7)% and (46+/-18)% of (210)Pb and (137)Cs under woodland canopy soils relative to open grassland soils, respectively. The enhancement factors are broadly in line with other independent findings in literature. Enhancement of both (210)Pb and (137)Cs in woodland soils relative to moorland soils is, in part, due to deposition by impaction during air turbulence, wash-off, gravitational settling and deposition during leaf senescence. Results of this study suggest that these processes affect both (210)Pb and (137)Cs carrier aerosols in a similar way.

Cesium Radioisotopes↗
PubMed1994

Tumour affinity of 203Pb-chloride: comparison with 67Ga-citrate and 201Tl-chloride.

The radionuclide 203Pb decays completely by electron capture to stable 203Tl with a half-life of 52 h. The primary radiation from the decay is gamma-ray radiation 280 keV (80%). 203Pb is produced easily from the natural metal thallium by the method described below. 203Pb-chloride is a promising imaging agent for tumour scanning because of the large retention value for tumour tissue and the small value for normal organs, but the large value for the kidney and bone is a shortcoming when considering it as an imaging agent. The retention value of 203Pb in tumour tissue is larger than that of 201Tl and smaller than that of 67Ga. The tumour/inflammatory lesion retention ratio for 203Pb is very large in comparison with those for 67Ga and 201Tl. 203Pb accumulates to a large extent in viable tumour tissue, and less in necrotic tumour tissue and in inflammatory lesion. Therefore, 203Pb-chloride is far better for visualization of viable tumour tissue than 67Ga and 201Tl if the large retention values for the kidney and bone were reduced.

Animals↗
PubMed2006

Long-term monitoring of radioactivity in surface air and deposition in New York State.

Gross-beta activities have been determined weekly for 22 y from filtered atmospheric aerosols at seven sites in New York State. The activities, ranging from 0.1 to 0.9 mBq m(-3), varied seasonally and were evaluated in terms of meteorological factors. Cosmogenic beryllium (7Be) concentrations were determined quarterly on the air filters and weekly in deposition collected at one site. Over 98% of the air filters contained observable activity concentrations of 7Be (mean of 3 mBq m(-3)) and 210Pb (mean of 1 mBq m(-3)). However, only 20% of deposition samples contained Be concentrations above analytical detection limits. Tritium (3H) concentrations were below detection limits in deposition samples at the background site, but were present on most samples collected near a H-processing facility. Measurements of 131I were conducted weekly on charcoal canisters, with only one site showing observable concentrations (mean of 1 mBq m(-3)), due to nearby incineration of dried municipal sludge containing patient waste from hospital treatments.

Air Pollutants, Radioactive↗
PubMed1998

Stress fracture of the sixth rib in an elite athlete.

We report on a previously unreported site of rib stress fracture in an elite athlete. A 27 year old sweep rower, a National champion and an Olympic finalist, presented with a 3-day history of the left-side thoracic pain. Technetium 99m bone scintigraphy showed increased focal uptake of the radioisotope, leading to the diagnosis of stress injury of the anterolateral part of the sixth rib. The probable mechanism of this injury was that strong muscle force itself was great enough to produce a fracture. In the case of our rower, the precipitation cause was only a slight change in the rowing technique, in contrast to all other reports on such rib fractures among rowers where the primary cause was an increase in the level of strength training. The treatment included a complete rest of the affected area and upper extremities, while the cardiovascular and strength fitness was maintained. The athlete was able to resume with his standard training routine less than four weeks after the onset of the symptoms.

Adult↗
PubMed1998

The biogeochemistry of an ombrotrophic bog: evaluation of use as an archive of atmosphere mercury deposition.

The utility of ombrotrophic bogs as archives of atmospheric mercury deposition was assessed with an investigation in Arlberg Bog, Minnesota, U.S.A. Since the use of ombrotrophic bogs as archives depends on the immobility of deposited trace metals, we examined the postdepositional transport processes revealed by the solid-phase distributions of mercury and ancillary metals (Fe, Al, Mn, and Pb) in this bog. We modeled metal speciation in bog porewaters as a function of pe in order to understand metal behavior in ombrotrophic peat. Specifically, we considered the effect of water movement and resultant shifts in redox potential gradients on metal retention. Our results indicate that Hg and Pb are immobile in ombrotrophic peat, so their distribution can be used to determine temporal changes in deposition. To substantiate the deposition estimates determined in this study, we emphasized the importance of confirming the validity of the dating scheme, assessing the degree of horizontal homogeneity in the accumulation record, and providing evidence for retention of Hg based on geochemical modeling. As recorded in Arlberg Bog, historic atmospheric Hg deposition increased gradually after the mid-1800s, peaked between 1950 and 1960, and may have declined thereafter. Preindustrial deposition was about 4 micrograms/m2 year and recent deposition about 19 micrograms/m2 year. The results of this study indicate that deposition at Arlberg Bog has been influenced by a regional and/or local-scale source.

Air Pollutants↗
PubMed1989

Radionuclides in shoreline waters of the northeast Irish Sea.

The shoreline waters of the Irish Sea along the Cumbrian coast near the British Nuclear Fuels plc works at Sellafield have been sampled at three locations over a 31/2 year period from December 1980. The particulate content was analysed for 238Pu, 239 + 240Pu, 241Am, 137Cs and stable Al. In some cases the radionuclide concentrations in filtered seawater were also determined. The results showed that the suspended particulate loads were high (typically about 100 mg l-1) and variable, and that they contained about 65 mg g-1 of aluminium. The isotopic ratio 238Pu/239 + 240Pu, which can indicate the chronology of the discharge, was about 0.26, which suggested that the Sellafield discharges over at least 5 years contributed to the observed concentrations. The 239 + 240Pu and 241Am annual average concentrations in the particulate material were in the ranges 3.0-5.1 and 3.3-5.2 Bq g-1, respectively. The individual values were very variable in time, but highly correlated with each other. No significant downward trends in the concentrations could be identified over this period. This is consistent with the behaviour of a reservoir (the northeast Irish Sea) where Pu and Am, which are available for suspension in particulate material, are fed by the Sellafield discharges and are subject to a mean removal time of several years. Thus the effects of the large reduction in the Sellafield discharges which occurred over this period should only be observable over a longer time interval. The concentrations in the dissolved fractions in seawater were negligible compared with the particulate fraction concentrations, in sharp contrast with the situation in offshore seawater.(ABSTRACT TRUNCATED AT 250 WORDS)

Americium↗
PubMed2001

Qualitative estimates of soil disturbance in the vicinity of CANDU stations, utilizing measurements of 137Cs and 210Pb in soil cores.

Anthropogenically derived 14C has been used to trace recent carbon input in a study of carbon accumulation and turnover in Canadian soils. In order to do so, documentation of the undisturbed nature of the soil horizons sampled was of prime concern. Although all the sites chosen for coring were currently uncultivated, detailed information on long-term land usage was not available. To overcome this problem, 137Cs profiles were measured in all the cores used in the study. 210Pb measurements were also made in cases where total 137Cs deposition was lower than predicted. For some sample sites, the data obtained showed correlated losses of both radionuclides, indicating that land disturbance and/or erosion had indeed occurred in these areas over the past 50 years, hence invalidating the use of those cores for carbon cycling studies. In a few cases a marked lack of correlation between these two radionuclides has made it necessary to hypothesize that chemical, rather than physical, processes have been partially responsible for the observed anomalies. Since results of this nature raise doubts about the reliability of the 137Cs method for identification of land disturbance, further investigation is warranted.

Agriculture↗
PubMedDate not supplied

[Size distribution of artificial and natural radioactive aerosols in the 30-kilometer zone of the Chernobyl AES in 1986-1996].

During 10 years after the Chernobyl accident the systematical measurings of size distributions of radioactive aerosols were conducted near the block-IV. In the ground level the active median aerodynamic diameters (AMAD) of 137Cs aerosols were ranged from 0.4 up to 1.4 microns in May, 1986. In that time the aerosol carriers of radioactive Te, Ru and I had AMAD 0.3 ... 0.5 micron. During 1987-1996 AMAD of aerosol of fission products of the Chernobyl accident was stable in range 4 ... 7 microns. Simultaneously concentrations and size distributions of natural radioactive aerosols were determined. The cosmogenic 7Be aerosols had AMAD 0.5 ... 0.7 micron. AMAD of the aerosols of daughter products of radon and thoron was found 0.4 ... 0.6 micron.

Aerosols↗
PubMed2002

Variation of the activity concentrations and fluxes of natural (210Po, 210Pb) and anthropogenic (239,240Pu, 137Cs) radionuclides in the Strait of Gibraltar (Spain).

The activity concentrations and fluxes of natural (210Pb, 210Po) and anthropogenic (239,240Pu, 137Cs) radionuclides have been determined in the different water masses crossing the Strait of Gibraltar. New data have been gathered during four multidisciplinary and multinational sampling campaigns, performed between 1997 and 1999 within the framework of the CANIGO-FLUGIST Project. Mean activity concentrations of 210Po (1.53+/-0.34 Bq m(-3), n = 30) and 210Pb (1.16+/-0.50 Bq m(-3), n = 31) in the Atlantic water entering the Mediterranean basin are about double those measured in the Mediterranean outflow, namely 0.84+/-0.34 Bq m(-3) (n = 22) for 210Po and 0.66+/-0.34 Bq m(-3) (n = 22) for 210Pb. The opposite trend is observed for 231,240Pu, with average concentrations of 9.9+/-3.0 mBq m(-3) (n = 29) in the incoming Atlantic flow and 22.0+/-3.0 mBq m(-3) (n = 22) in the outpouring Mediterranean water. In the case of 137Cs, the same concentrations were quantified in the waters moving inwards (2.52+/-0.28 Bq m(-3), n = 27) and outwards (2.14+/-0.52 Bq m(-3), n = 21) from the Mediterranean Sea. On this basis, the Mediterranean basin experiences a net annual input flux of 14 TBq of 210Pb and 19 TBq of 210Po, and a net annual loss of 0.34 TBq of 239,240Pu, while--at present--137Cs input and output fluxes appear to be balanced.

Cesium Radioisotopes↗
PubMed2003

Formation of radioactivity enriched soils in mountain areas.

A field study was carried out in the Mercantour Mountains at 2200 m altitude to investigate the processes of soil enrichment in atmospheric Chernobyl (137)Cs. Soils with high (137)Cs activities have been collected in the pasture areas with frequently measured (137)Cs activity values of the order of 7000 Bq m(-2). At some single spots (about 6% of the studied area), activity in soils reached 300000 Bq m(-2), which represents 44% of the (137)Cs of the total area. Data further showed that spatial distribution of Cs depends widely on its origin: Chernobyl Cs is mainly concentrated in "enriched" soils, whereas older Cs and (241)Am fallout from nuclear weapons tests (NWTs) and natural atmospheric (210)Pb in soils is less heterogeneously distributed. In order to elucidate the processes which have led to the enrichment in Chernobyl (137)Cs in the Alps in May of 1986, we have studied the repartition of atmospheric (7)Be isotope (half-life=53.3 d) in the pasture compartments (soil, litter, grass, and snow). Snow (7)Be data give evidence that fallout enrichment is related to snow accumulation (snow drift). The transfer of beryllium occurs rapidly to the grass and litter, where the strongest pollutant accumulations were measured. However, (7)Be transport to the soil required more than 8 months.

Altitude↗
PubMed2001

Reinvestigation of airborne 210Pb, 137Cs and 207Bi in Vienna (Austria) after atmospheric nuclear weapons tests.

Reconstruction of atmospheric 210Pb and 137Cs activity concentrations occurring in Vienna immediately after the atmospheric nuclear weapons tests shall answer the question, whether artificial 210Pb has been produced by fusion devices using lead materials. If so, 207Bi also can be expected. In 1962, weekly average values for 210Pb were between 0.08 +/- 0.02 and 1.31 +/- 0.30 mBq/m2, 137Cs amounts up to 5.1 +/- 0.6 mBq/m3. 207Bi remains below the detection limit, viz. < 0.5 mBq/m3. Bimonthly averages for the periods 1962-1964 and 1974-1975 show 137Cs activity concentrations with typical springtime maxima occurring together with low 210Pb values and 207Bi < 0.02 mBq/m3. Annual averages of 210Pb are varying between 0.27 and 0.53 mBq/m3, independent of whether atmospheric tests have been performed or not. Comparison of the activity ratios 207Bi/210Pb, 207Bi/137Cs and 210Pb/137Cs with published data, leads to the conclusion that no evidence exists for a significant production of 210Pb by nuclear explosions, neither after the Soviet tests in 1961-1962 nor after the Chinese tests in 1973-1976.

Air Pollutants, Radioactive↗