Photosynthetic Activity in Marine and Brackish Water Strains of Fucus vesiculosus and Fucus radicans (Phaeophyceae) at Different Light Qualities

This study investigates the effects of different light qualities on the photosynthetic capacity of the brown algae Fucus vesiculosus, from the Norwegian Sea, and Fucus radicans and F. vesiculosus, from the Bothnian Sea. The electron transport rates (ETR) obtained for F. vesiculosus from the Norwegian Sea showed significantly higher levels of light saturation compared with both species of algae from the Bothnian Sea. The maximum of ETR values for the Norwegian Sea strain showed no significant changes due to varying light quality compared with the initial values. For F. vesiculosus, from the Bothnian Sea, treatment with blue light showed an effect after 1 week of 30 and 90 μmol photons m^?2 s^?1 (P < 0.01), and for F. radicans from the Bothnian Sea, at the irradiance of 90 μmol photons m^?2 s^?1 and 1 week (P < 0.01). After 1 week in the Bothnian Sea species and after 2 weeks in F. vesiculosus from the Norwegian Sea, the photosynthetic efficiency (α) was significantly higher regardless of light quality and irradiance compared with the initial values. Variation in light quality and irradiance had minor effects on the F_v:F_m values of the three algal strains studied.     

Determination of technetium-99 from the aspect of environmental radioactivity

A radioanalytical procedure has been developed for the determination of⁹⁹Tc in environmental samples. The procedure consists of precipitation, solvent extraction, ion exchange, electrodeposition and radiation measurement. Rhenium was used as a non-isotopic carrier of⁹⁹Tc. On the basis of 3σ counting error, the detection limits were 4.9·10^?5 Bq/l, 7.4·10^?3 Bq/kg wet and 7.4·10^?2 Bq/kg dry for water, biota and soil samples, respectively. Sea water, seaweeds (brown algae) and soils were collected to evaluate the present levels of⁹⁹Tc in Japan. The level of⁹⁹Tc in sea water was ca. 1·10^?4 Bq/l around Japan. Among the seaweeds (brown algae), Ishige okamurai showed the highest concentration of 5.8·10^?2 Bq/kg wet tissue and the highest concentration factor of 583. The level of⁹⁹Tc in the organic rich surface soil was ca. 1 Bq/kg dry soil in Fukuoka.     

Development of a radiochemical neutron activation analysis procedure for determination of rhenium in biological and environmental samples at ultratrace level

Summary Radiochemical neutron activation procedures using liquid-liquid extraction with tetraphenylarsonium chloride in chloroform from 1M HCl and solid extraction with ALIQUAT 336 incorporated in a polyacrylonitrile binding matrix from 0.1M HCl were developed for accurate determination of rhenium in biological and environmental samples at the sub-ng ^. g^-1 level. Concentrations of Re in the range of 0.1 to 2.4 ng ^. g^-1 were determined in several botanical reference materials (RM), while in a RM of road dust a value of ~10 ng ^. g^-1 was found. Significantly elevated values of Re, up to 90 ng ^. g^-1 were found in seaweed (brown algae). Results for Re in the brown algae Fucus vesiculosus in which elevated ⁹⁹Tc values had previously been determined suggested possible competition between Re and Tc in the accumulation process.     

Determination of technetium-99 in aqueous samples by isotope dilution inductively coupled plasma-mass spectrometry

An isotope dilution/inductively coupled plasma mass spectrometric method (ID/ICP-MS) for measuring the concentration of technetium-99 in aqueous samples was developed at the Savannah River Technology Center (SRTC). The procedure is faster than radiometric tecniques, is less subject to interferences, and has equal or better detection limits. It is currently being used to measure the concentration of⁹⁹Tc in samples of Savannah River water collected in the vicinity of the Savannah River Site. In this method one liter samples of water are spiked with⁹⁷Tc. After equilibration, the technetium is extracted from the sample with a chromatographic resin. Interfering elements, molybdenum and ruthenium, are either not retained by the resin or are washed off with, dilute nitric acid. The technetium is then eluted with more concentrated nitric acid, and the⁹⁹Tc/⁹⁷Tc ratio in the eluant is measured with an ICP-MS. The⁹⁹Tc concentration in the original sample is calculated from the⁹⁹Tc/⁹⁷Tc ratio. The chemical recovery of the extraction procedure is greater than 90%. The detection limit of the instrument, taken as three times the background counts atm/z=99, is 0.6 part per trillion (ppt). The detection limit of the procedure, taken as three times the standard deviation of several reagent blank analyses, is 0.33 pCi/l.     

Distribution of 99Tc and 129I in the vicinity of underground nuclear tests at the Nevada Test Site

⁹⁹Tc and ¹²⁹I are important contributors to risk assessment due to their long half-lives and high mobility as aqueous anionic species. We analyzed ⁹⁹Tc and ¹²⁹I in groundwater samples in and near 11 underground nuclear tests and in melt glass and rock samples retrieved from the Chancellor test cavity, Nevada Test Site. The ¹²⁹I/¹²⁷I ratio ranges from 10⁻³ to 10⁻⁶ in cavity water and 10⁻⁴ to 10⁻⁹ in satellite wells. The ⁹⁹Tc concentration ranges from 3 to 10⁻⁴ Bq/l in cavity waters and from 0.3 to 10⁻⁴ Bq/l in satellite wells. Downstream migration is apparent for both radionuclides. However, it is affected by both retardation and initial distribution. In-situ ⁹⁹Tc and ¹²⁹I K _d s calculated using rubble and water concentrations are 3 to 22 ml/g and 0 to 0.12 ml/g, respectively, and are suggestive of mildly reducing conditions. ¹²⁹I distribution in the melt glass, rubble and groundwater of the Chancellor test cavity is 28%, 24% and 48%, respectively, for ⁹⁹Tc, it is 65%, 35% and 0.3%, respectively. Our partitioning estimates differ from those of underground tests in French Polynesia, implying that fission product distribution may vary from test to test. Factors that may influence this distribution include geologic conditions (e.g., lithology, water and CO₂ content) and the cooling history of the test cavity.     

Distribution and behaviour of99Tc,237Np,239,240Pu,and241Am in the coastal and estuarine sediments of the Irish Sea

Intertidal coastal and estuarine sediments from 24 sites in the Irish Sea have been analyzed for⁹⁹Tc,²³⁷Np,²³⁸Pu,^239,240Pu and²⁴¹Am. The²³⁷Np activity and²³⁹Pu/²⁴⁰Pu ratio were measured simultaneously by ICP-MS, and⁹⁹Tc was determined by HR-ICP-MS which is ten times more sensitive than Q-ICP-MS.The activities of⁹⁹Tc,²³⁷Np,^239,240Pu and²⁴¹Am were distributed over a wide range of 1.5–70.5, 0.01–13.3, 2.3–1589, 2.6–1894 Bq/kg, respectively. Activities of these radionuclides decreased exponentially with distance from the Sellafield source. The²⁴¹Am/^239,240Pu and²³⁷Np/^239,240Pu ratios were almost constant with distance from the Sellafield. This result suggests that the distribution and behavior of Np and Pu are controlled by complicated factors such as the influence of transport, the variation with time of Np/Pu ratio in the Sellafield discharges and sedimentary mixing processes in the Irish Sea.     

Etude de la dispersion du technetium-99 sur les côtes françaises de la manche à l'aide de deux indicateurs biologiques:Fucus sp. etPatella sp.

Determination of⁹⁹Tc in two biological indicators,Fucus sp. andPatella sp., of the French coast of the Channel showed that this radionuclide found in small amounts, was dispersed eastwards from the La Hague reprocessing fuel plant. However,⁹⁹Tc trace amounts were also detected in the river Seine bay and in the bay of Mont St. Michel, which confirms the great mobility of this element.      

Temporal variations of iodine-127, potassium-40 and technetium-99 concentrations in Fucus serratus in the English Channel

The trends of¹²⁷I,⁴⁰K, and⁹⁹Tc levels were measured for several years inFucus serratus collected in 3 different Channel coastal stations. The results demonstrated cyclic seasonal variations of the levels, with maximum values in winter and minimum values in summer (ranging between 2 and 3). Ash levels evolved with a similar cycle, which allowed to estimate that the cycle thus observed was related to the alga biological activity and not to the releases. Trends of⁹⁹Tc levels were more complex. At Roscoff, a station little exposed to the releases, levels varied with the same annual cycle as natural elements. At Herquemoulin, a station close to the release point, the trend was mainly related to the released activities with a delay of about 1 year. At Wimereux, a distant station more strongly affected by sea currents, the cycle appeared in 1983 and 1984 but was hidden in 1985 and 1986 by the arrival of waters more strongly labelled because of the larger releases that occurred in 1985 (26 TBq), instead of 12 TBq in 1983 and 1984.     

Comparison of a radiation counting method and ICP-MS for the determination of99Tc in environmental samples

Results of⁹⁹Tc measurements between radiation and non-radiation counting methods were compared using four radiation sources for which⁹⁹Tc has been previously determined with a gas-flow proportional counter or a GM counter. Each⁹⁹Tc source consisted of a stainless steel planchet bound by mylar films. Seaweeds collected from the Irish Sea were analyzed and⁹⁹Tc was electroplated on the planchet. The⁹⁹Tc in each sample was separated and measured again by inductively coupled plasma mass spectrometry (ICP-MS). Tc was continuously removed from each sample with 2M HNO₃ and 2M NaOH. After the solution containing Tc was adjusted to 0.1M HNO₃, Tc was extracted on a novel extraction chromatographic resin to separate it from Ru. The total recoveries for Tc on the planchet samples were almost the same with an average of 91%. The results of⁹⁹Tc measurements by both radiation and non-radiation counting methods agreed well with each other.     

Determination of99Tc in coastal seawater collected in Fukuoka,Japan

Concentrations of⁹⁹Tc were determined by inductively coupled plasma mass spectrometry (ICP-MS) on coastal seawater in the general environment in Japan. Technetium was enriched on iron hydroxide by repetitive co-precipitation method from a large volume of seawater and separated from impurities by solvent extraction and ion-exchange techniques. The concentrations of⁹⁹Tc were 1.0 to 7.4 Bq1^–1, which was one order of magnitude lower than the level reported on seawater from general environment by beta-ray counting. Concentrations of¹³⁷Cs determined on the same seawater were 3.7 and 3.9 mBq1^–1. The activity ratio of⁹⁹Tc/¹³⁷Cs was calculated to be 2.7×10^–4. This ratio was very close to the value expected for fallout from nuclear tests.     

Determination of low-level99Tc in environmental samples by high resolution ICP-MS

An analytical method has been developed for the determination of low-level⁹⁹Tc in environmental samples by High Resolution ICP-MS. The method consists of leaching of⁹⁹Tc by HNO₃ and separation by three different solvent extractions with 30% TOA-xylene, MEK, and cyclohexanone. Finally, purification of⁹⁹Tc was made by using an anion exchange resin column to reduce dissolved solids content. The final solution was adjusted to 1M HNO₃ for introducing into the HR-ICP-MS. The accuracy and precision of the method was confirmed to be satisfactory by applying this technique to the determination of⁹⁹Tc in IAEA marine algae sample (AG-B-1). Measurements of⁹⁹Tc using 0.5–2.5 g of sediment samples from the Irish Sea, UK, were successfully performed by the present method.     

Presence of uranium and plutonium in marine sediments from gulf of tehuantepec, mexico

Uranium and plutonium were determined in the Tehua II-21 sediment core collected from the Gulf of Tehuantepec, Mexico. The analyses were performed using radiochemical separation and alpha spectroscopy. Activity concentrations of alpha emitters in the sediment samples were from 2.56 to 43.1 Bq/kg for ²³⁸U, from 3.15 to 43.1 Bq/kg for ²³⁴U and from 0.69 to 2.95 Bq/Kg for ^239+240Pu. Uranium activity concentration in marine sediment studied is generally high compared with those found in sediments from other marine coastal areas in the world. The presence of relatively high concentrations of anthropogenic plutonium in the sediments from the Gulf of Tehuantepec suggests that anthropogenic radionuclides have been incorporated and dispersed into the global marine environment.     

Polybrominated diphenyl ethers in Baltic herring from Estonian waters, 2006–2008

Concentrations of polybrominated diphenyl ethers (PBDEs) in Baltic Sea herring Clupea harengus membras L. collected from Estonian coastal waters are reported. In the period 2006–2008 the total PBDE concentrations (ΣPBDE, sum of 15 congeners) in Baltic herring varied between 0.57 and 4.08 ng g⁻¹ fresh weight. Highest ΣPBDE concentrations were in a 2007 sample from the mouth of the Gulf of Finland and in a 2007 sample from the Gulf of Riga. The former contained a high concentration of BDE 209 (16.3 ng g⁻¹) and in the latter this congener was the second most abundant. It is not clear whether the BDE 209 concentration in the Gulf of Finland sample is not an artefact and this value was not included in the above range. The PBDE concentrations increased with the age of herring are similar to those reported in [1] in fish collected in the Bothnian Sea in 2002 and did not increase between 2002 and 2008. The majority of concentrations in herring from the Estonian coastal zone was <1.0 ng g⁻¹ fresh weight. The PBDE congener profiles varied regionally as well as with age of the fish. The main congeners were mostly the BDEs 47, 99, and 100. Some of the variations probably caused by measurement artefacts.     

Determination of99Tc in reactor loop decontamination liquid waste using extraction chromatography

A new analytical method has been developed to determine⁹⁹Tc in samples of aqueous radioactive waste containing high levels of⁶⁰Co (10³–10⁶ Bq/l) in mixed forms (simple cationic⁶⁰Co²⁺ and coordinated complex forms). The method consists of selective extraction of the⁹⁹Tc with a combination of cation exchange and solid-phase extraction resins under strong acid conditions. Quantification of the isolated⁹⁹Tc is accomplished using liquid scintillation counting. The method provides high recoveries (>98%), is simpler than classical solvent extraction methods, eliminates the use of chlorinated organic solvents and the time of analysis is reduced by a factor of 2 when compared to solvent extraction methods.     

On variations of volumetric activity of 90Sr and 137Cs in the Baltic Sea coastal waters near the shore of Lithuania in 2005–2009

The article presents the measurement results of the volumetric activity (VA) of artificial radionuclides ⁹⁰Sr and ¹³⁷Cs in the coastal waters of the Baltic Sea near the Curonian Peninsula in 2005–2009. The annual average values for this period of time were 12 Bq/m³ (⁹⁰Sr) and 40 Bq/m³ (¹³⁷Cs). Considerable variations in the VA of the radionuclide in individual measurements compared to the average results were observed. The extreme values were 6 and 16 Bq/m³ for ⁹⁰Sr and for ¹³⁷Cs—27 and 75 Bq/m³. It is proposed to allow such variations under the influence of a variety of external factors such as hydro meteorological situations, inflowing rivers and bays, storm activity and etc. Besides, a possibility of penetration of radionuclides into the sea waters from the additional radioactive sources is not excluded.     

Radionuclide uptake in red macroalgae from the Bulgarian Black Sea coast

Summary Technogenic and natural radionuclide content in red macroalgae (Ceramium rubrum, Corallina officinalisand Callithamnion corymbosum) from the Bulgarian Black Sea coast, collected in the period 1992-2003, was studied by low-level gamma-spectrometry. The data show that the nuclide concentrations depend on macroalgae species and coast locations. The highest nuclide content was measured in Ceramium rubrumspecies. The ¹³⁷Cs mean value is 9.8 Bq/kg, 19.6 Bq/kg for ²²⁶Ra and 17 Bq/kg for ²¹⁰Pb. The radionuclide pollution is considerably small due to the absence of nuclear facilities along the Bulgarian Black Sea coast.     

An improved method for technetium determination in environmental samples

Summary The recent developments of extraction chromatography and ICP-MS made easier the determination of ⁹⁹Tc in environmental samples. However, in the non-contaminated area, a pre-concentration procedure is necessary, because usually a large amount of sample is used for analysis. In this study, the ferrous ion (Fe²⁺) added as a reductant can make chemical yield from 50 to 80%, when larger than 100 liter water samples or 500 g soil samples are analyzed. The extraction chromatography with TEVA resin (EIChrom) and the measurement by ICP-MS have been developed using ^95mTc and ¹⁰³Ru as yield tracers. Detection limits of 3σ are 0.054 mBq/kg for 500 g soil and 0.032 µBq/lfor 500 l water. A pond named Hinotani, Mie Prefecture in the central part of Japan, was selected to be investigated as a natural system in a non-contaminated area. Surface soil near this pond, pond water and sediment were collected and analyzed for ⁹⁹Tc. In a high fall-out area, Okuetsu, Fukui Prefecture forest soil was collected and analyzed. The ⁹⁹Tc in the surface (0-5 cm) was 10.5±0.8 mBq/kg. The ⁹⁹Tc in Hinotani surface (0-5 cm) soil were 0.77±0.06 mBq/kg less than in Okuetsu. Technetium-99 has been determined in pond water, sediment (0-5 cm) and shrimps in the Hinotani pond, 0.25±0.02 mBq/l, 3.3±0.3 mBq/kg, 1.5±0.2 mBq/kg, respectively.     

The lignin of the algaFucus vesiculosus

Summary 1. The plant material ofFucus vesiculosus has been treated with metallic sodium in liquid ammonia. The total yield of products extractable by ether was 1.1%.2. In the products of the decomposition of the lignin ofFucus vesiculosus 12 phenols and acids have been identified by paper chromatography and gas-liquid chromatography and it has thereby been established that the lignin of algae consists of p-coumaryl, guaiacyl, and syringyl structural units.3. The composition of the decomposition products confirms the hypothesis expressed previously that the brown algaFucus vesiculosus contains lignin.S. M. Kirov Belorussian Technological Institute, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 645–647, September–October, 1978.     

Comparison of the TEVA-Spec resin and liquid-liquid extraction methods for the separation of technetium in soil samples

When ICP-MS is used for⁹⁹Tc measurements, elements which interfere with⁹⁹Tc counting should be removed. In this study, a separation method using a novel chromatographic resin (TEVA·Spec^® resin) was compared with a liquid-liquid extraction (LLX) method for separation and concentration of⁹⁹Tc which was trapped in a solution after combustion of environmental soil samples. The results showed that Tc could be separated from Ru at high recoveries with both separation methods. Molybdenum, however, was not removed by LLX, while more than 99% of Mo in soil samples were removed by TEVA·Spec resin.     

Extractive scintillating resin for 99Tc quantification in aqueous solutions

A method utilizing extractive scintillating resin for ⁹⁹Tcmonitoring in aqueous solutions is presented. These extractive scintillatorscombine analyte selective uptake and scintillating properties to produce dualfunctionality analytical resins. These resins were produced by (1) co-locatedextraction chromatographic resin and plastic scintillating beads, (2) immobilizingfluors in macroporous polystyrene supports to which chains of monomethylatedpolyethylene glycol have been grafted and (3) co-immobilizing organic scintillatingfluors and a quaternary ammonium extractant (Aliquat-336) within macroporousacrylic and polystyrene supports. The first and third resins selectively extractpertechnetate ions from dilute acid whereas the second resin selectively extractspertechnetate ions from high ionic strength solutions. These resins were utilizedin ~0.20 ml pore volume columns while ⁹⁹Tc was continually monitoredwith commercially available scintillation detection systems. Manual and automatedmicrofluidics were used to deliver sample and reagent solution for loadingand elution of the ⁹⁹Tc. The detection efficiencies were determinedto be 45 and 70% for acrylic and polystyrene based resins, respectively, andindependent of extractant. Minimum detectable ⁹⁹Tc concentrationusing the Aliquat-336/acrylic-based resin was 6.2 Bq . l –1 for a 50-mlsample and 30-minute count time. The new methodology was applied towards analysisof contaminated groundwater samples and nuclear waste simulants.