Countermeasures for animal products: a review of effectiveness and potential usefulness after an accident.

Over the last decade, there has been considerable progress in the development of countermeasures for preventing or reducing contamination of animal products by radioisotopes of iodine, caesium and strontium. In this paper, recent significant technical improvements are summarised and the current availability of countermeasures and their usefulness in the event of a nuclear accident reviewed. An improved understanding of factors controlling the metabolism of radioiodine and radiostrontium has enabled previously suggested countermeasures to be either optimised or dismissed. For radiocaesium in particular, experience since the Chernobyl accident has enabled effective and feasible countermeasures to be identified and successfully implemented in different situations. It has also been more widely understood that countermeasure effectiveness, although important, is not the only criterion which needs to be determined. In addition, cost and practical considerations such as availability, technical feasibility, acceptability and side-effects need to be taken into account. Evaluation of these factors has shown that some previously recommended countermeasures are unlikely to be feasible.     

Do changes in risk-taking affect habitat shifts of sticklebacks?

The distribution of individuals is often the outcome of conflicting demands, such as between predator avoidance and reproduction. A factor that has seldom been considered in studies on habitat choice is time-dependent changes in risk-taking. We investigated the distribution of threespine sticklebacks, Gasterosteus aculeatus, over two breeding seasons and found it to change with time towards shallower areas with a more open habitat structure. Shallow and structurally less complex habitats were probably favorable due to a higher reproductive rate, but costly due to an increased risk of predation. Contrary to expectation, changing predation pressure was not a predictor of the shift in habitat use and, thus, not the proximate cue. Instead date was the main predictor. This suggests that increased risk-taking in relation to predation contributed to the habitat shift. The possibility was supported by a laboratory experiment that showed sticklebacks to take larger risks and prefer more predator-exposed areas at the end of the season than at the start of the season. These results demonstrate that temporal changes in risk-taking occur and can influence habitat choice, which points to the importance of considering risk-taking, in addition to predation pressure, when studying the effect of predators on distribution.Communicated by J. Krause     

Rapid karyotyping in prenatal diagnosis: A comparative study of the ‘pipette method’ and the ‘in situ’ technique for chromosome harvesting

Rapid karyotyping in the second and third trimesters has important implications for the management of pregnancies at risk. From September 1985 to March 1992, 735 amniotic fluid samples sent to our laboratory for rapid karyotyping from 64 different diagnostic centres of the Federal Republic of Germany were included in a comparative study on harvesting for chromosome analysis using the ‘pipette method’ or the ‘in situ’ technique. The average time between preparation of the amniotic fluid and verbal notification of the analysed karyotype was 5·41 days. The ‘pipette method’ needed on average 4·65 days, and the ‘in situ’ technique 5·97 days. In comparison with other more invasive techniques available for rapid karyotyping such as cordocentesis and placental biopsy, amniocentesis and subsequent chromosome harvesting using the ‘pipette method’ and/or the ‘in situ’ technique proved very useful and efficient. The overall incidence of chromosome aberrations was 15·3 per cent. The high rate of structural chromosome aberrations and uncommon aneuploidies found in our investigation (12 per cent) indicates that for rapid karyotyping in the second and third trimesters, conventional cytogenetic techniques cannot be replaced by faster techniques based on fluorescent in situ hybridization on interphase cells in the near future.     

The importance of glutathione and phytochelatins on the selenite and arsenate detoxification in Arabidopsis thaliana

We investigated the role of glutathione(GSH) and phytochelatins(PCs) on the detoxification of selenite using Arabidopsis thaliana. The wild-type(WT) of Arabidopsis thaliana and its mutants(glutathione deficient Cad 2–1 and phytochelatins deficient Cad 1–3) were separately exposed to varying concentrations of selenite and arsenate and jointly to both toxicants to determine their sensitivities. The results of the study revealed that, the mutants were about 20-fold more sensitive to arsenate than the WT, an indication that the GSH and PCs affect arsenate detoxification. On the contrary, the WT and both mutants showed a similar level of sensitivity to selenite, an indication that the GSH and PCs do not significantly affect selenite detoxification. However, the WT is about 8 times more sensitive to selenite than to arsenate, and the mutants were more resistant to selenite than arsenate by a factor of 2. This could not be explained by the accumulation of both elements in roots and shoots in exposure experiments. The co-exposure of the WT indicates a synergistic effect with regards to toxicity since selenite did not induce PCs but arsenic and selenium compete in their PC binding as revealed by speciation analysis of the root extracts using HPLC–ICP–MS/ESI–MS. In the absence of PCs an antagonistic effect has been detected which might suggest indirectly that the formation of Se glutathione complex prevent the formation of detrimental selenopeptides. This study, therefore, revealed that PC and GSH have only a subordinate role in the detoxification of selenite.     

Photodegradation of the antibiotic spiramycin studied by high-performance liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry

The degradation of spiramycin induced by ultraviolet (UV) irradiation was studied at pH 3–4, 6–7 and 8–9 using high-performance liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry. Furthermore, the influence of hydrogen peroxide and oxygen on the photodegradation was investigated. Three degradation products were observed in the presence of oxygen and four in the absence of oxygen. The degradation kinetics were monitored as mass area-time curves, analyzed and described using subsequent follow-up reaction first-order models. The m/z values of the degradation products were determined to be 160, 322 and 366, the latter representing two separate products, the sugar moieties of spiramycin. Remainders of the macrocycle or the intact lactone ring of spiramycin were not observed, since the conjugated π-electron system was assumed photoexcited and thus undergoing photodegradation and fast destruction of the ring. The kinetic of the degradation of spiramycin itself was described using a first-order model. The degradation was accelerated upon addition of hydrogen peroxide. In contrast, systematic acceleration depending on pH could not be found. The absence of oxygen did not lead to any significant acceleration. The findings are interpreted in terms of the effectiveness of advanced oxidation processes and their potential use as a fourth purification step in wastewater treatment plants.     

Influence of altitude concerning the contamination of humus soils in the German Alps: a data evaluation approach using PyHasse

Background, aim and scope  

In an international project named MONARPOP (Monitoring Network in the Alpine Region for Persistent and other Organic Pollutants), selected chemicals in different environmental media were analysed in the years 2004 and 2005. Seventeen pesticides were chosen and analysed in humus and mineral soil in the German Alps. The samples were taken at different altitudes.     

Response to W. Kramer: The human sex odds at birth after the atmospheric atomic bomb tests,after Chernobyl,and in the vicinity of nuclear facilities: comment (doi:10.1007/s11356-011-0644-8)

Introduction

This paper is in response to criticism of our article “The human sex odds at birth after the atmospheric atomic bomb tests, after Chernobyl, and in the vicinity of nuclear facilities” published in Environ Sci Pollut Res 18(5):697–707, 2011.

Methods

Our findings and methods concerning the disturbed human sex odds at birth have been criticized in this journal for being artifacts of data mining, that the concept of statistical significance was misunderstood, and that confounding factors have not been accounted for. Here, we show that this criticism has no basis. We applied well-established statistical methods to large official data sets, and confounding is less important at the level of secular sex odds trends in aggregated annual figures from countries or continents.

Results and conclusions

Moreover, our results are strengthened by recent findings concerning increased infant death sex odds in Germany and increased Down syndrome prevalence at birth across Europe after Chernobyl. Prompted by our studies, an official investigation in Lower Saxony, Germany, by the “Niedersächsisches Landesgesundheitsamt (NLGA)” confirmed our observation of severely escalated sex odds within 40 km distance from the nuclear storage site in Gorleben, Germany.