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In the beginning of April 2020, large fires that started in the Chernobyl Exclusion Zone (CEZ) established after the Chernobyl accident in 1986 caused media and public concerns about the health impact from the resuspended radioactivity. In this paper, the emissions of previously deposited radionuclides from these fires are assessed and their dispersion and impact on the population is examined relying on the most recent data on radioactive contamination and emission factors combined with satellite observations. About 341 GBq of 137Cs, 51 GBq of 90Sr, 2 GBq of 238Pu, 33 MBq of 239Pu, 66 MBq of 240Pu and 504 MBq of 241Am were released in 1st–22nd April 2020 or about 1,000,000,000 times lower than the original accident in 1986 and mostly distributed in Central and East Europe. The large size of biomass burning particles carrying radionuclides prevents long-range transport as confirmed by concentrations reported in Europe. The highest cumulative effective doses (> 15 μSv) were calculated for firefighters and the population living in the CEZ, while doses were much lower in Kiev (2–5 μSv) and negligible in Belarus, Russia and Europe. All doses are radiologically insignificant and no health impact o
2020
Environmental factors that can influence telomeres are diverse, but the association between telomeres and exposure to environmental contaminants is yet to be elucidated. To date, prior studies have focused on legacy persistent chlorinated pollutants (POPs), while the effects of poly- and perfluoroalkyl substances (PFAS) have been poorly documented. Here, we investigated the associations among PFAS congeners, absolute telomere length (cross-sectional approach), and telomere dynamics (rate of telomere length change over time, longitudinal approach) in one of the most contaminated arctic top predators, the glaucous gull Larus hyperboreus from Svalbard. We further estimated the effect of PFAS on apparent survival rates and re-sighting probabilities using a 10-year capture/recapture dataset (2010–2019). We found that birds exposed to higher concentrations of perfluorononadecanoate (PFNA) (median of 1565 pg/mL of ww in males and 1370 pg/mL of ww in females) and perfluorotetradecanoate (PFTeDA) (median of 370 pg/mL of ww in males and 210 pg/mL of ww in females) showed the slowest rate of telomere shortening. We also found that high blood concentrations of perfluorooctanoate (PFOA) (median of 120 pg/mL of ww in males and 150 pg/mL of ww in females) and perfluorohexanesulfonate (PFHxS) (median of 495 pg/mL of ww in males and 395 pg/mL of ww in females) were positively associated with higher re-sighting probabilities and apparent survival in males but not in females. Our work is the first to report an association between single PFAS compounds and telomeres, and the first to link PFAS exposure with survival probabilities, suggesting that the effect of PFAS exposure might be more tied to the type of compound rather than the total concentration of PFAS.
2020
Effects of titanium dioxide nanoparticles on the Hprt gene mutations in V79 hamster cells
The genotoxicity of anatase/rutile TiO2 nanoparticles (TiO2 NPs, NM105 at 3, 15 and 75 µg/cm2) was assessed with the mammalian in-vitro Hypoxanthine guanine phosphoribosyl transferase (Hprt) gene mutation test in Chinese hamster lung (V79) fibroblasts after 24 h exposure. Two dispersion procedures giving different size distribution and dispersion stability were used to investigate whether the effects of TiO2 NPs depend on the state of agglomeration. TiO2 NPs were fully characterised in the previous European FP7 projects NanoTEST and NanoREG2. Uptake of TiO2 NPs was measured by transmission electron microscopy (TEM). TiO2 NPs were found in cytoplasmic vesicles, as well as close to the nucleus. The internalisation of TiO2 NPs did not depend on the state of agglomeration and dispersion used. The cytotoxicity of TiO2 NPs was measured by determining both the relative growth activity (RGA) and the plating efficiency (PE). There were no substantial effects of exposure time (24, 48 and 72 h), although a tendency to lower RGA at longer exposure was observed. No significant difference in PE values and no increases in the Hprt gene mutant frequency were found in exposed relative to unexposed cultures in spite of evidence of uptake of NPs by cells.
2020
Pollutant concentrations are poorly known for the largest animals on Earth, blue whales Balaenoptera musculus and fin whales Balaenoptera physalus. In this study, concentrations of persistent organic pollutants (POPs) were determined in blubber biopsies and stable isotope values for nitrogen (δ15N) and carbon (δ13C) were measured using skin biopsies for 18 blue whales and 12 fin whales sampled in waters surrounding the Svalbard Archipelago, Norway. The samples were collected in summer during the period 2014–2018. POPs were dominated by DDTs, PCBs and toxaphenes, with median concentrations in blue/fin whales being 208/341, 127/275 and 133/233 ng/g lipid weight, respectively. Linear models indicated that pollutant concentrations were 1.6–3 times higher in fin whales than in blue whales, which is likely related to the higher trophic positions of fin whales, as indicated by their higher δ15N. Lower δ13C in fin whales suggests that they feed at higher latitudes than blue whales; these values were not correlated with pollutant concentrations. Pollutant levels were approximately twice as high in males compared to females (intraspecifically), which indicates that females of these species offload pollutants to their offspring during gestation and lactation, similar to many other mammalian species. Pollutant concentrations in balaenopterid whales from Svalbard waters were generally much lower than in conspecific whales from the Mediterranean Sea or the Gulf of California, but higher than those in conspecifics from the Antarctic Peninsula.
2020
Changes in the genetic material can lead to serious human health defects, as mutations in somatic cells may cause cancer and can contribute to other chronic diseases. Genotoxic events can appear at both the DNA, chromosomal or (during mitosis) whole genome level. The study of mechanisms leading to genotoxicity is crucially important, as well as the detection of potentially genotoxic compounds. We consider the current state of the art and describe here the main endpoints applied in standard human in vitro models as well as new advanced 3D models that are closer to the in vivo situation. We performed a literature review of in vitro studies published from 2000–2020 (August) dedicated to the genotoxicity of nanomaterials (NMs) in new models. Methods suitable for detection of genotoxicity of NMs will be presented with a focus on advances in miniaturization, organ-on-a-chip and high throughput methods.
2020
Active sampling methodology for atmospheric monitoring of cyclic volatile methylsiloxanes (cVMS) was improved to reduce sampling artifacts. A new sorbent, ABN Express (ABN), was evaluated for storage stability and measurement accuracy. Storage stability of cVMS on ABN showed less than 1% degradation of the individual 13C-labelled octamethylcyclotetrasiloxane (13C4-D4), decamethylcyclopentasiloxane (13C5-D5) and dodecamethylcyclohexasiloxane (13C6-D6) after 14 days storage at room temperature and at −20 °C whereas significant degradation was observed on ENV+ sorbent at room temperature (37–62 %) and −20 °C (9–16 %). 13C4-D4 formed on ENV+ spiked with 13C5-D5, and both 13C4-D4 and 13C5-D5 formed on ENV+ spiked with 13C6-D6. However, this was not observed on the ABN sorbent. Performance of ABN was compared to ENV+ through an 8-month Arctic sampling campaign at the Zeppelin Observatory (Ny Ålesund, Svalbard). Good agreement between ABN and ENV+ was observed for D4 in the spring/summer months. However, D5 and D6 was found to be consistently higher on the ABN sorbent during this time period with D6 showing the greatest deviation. During the winter months, larger deviations were observed between ABN and ENV+ sorbents with a factor of 4 times higher atmospheric concentrations of both D5 and D6 found on ABN; indicating sorbent related degradation on ENV+. Our findings show that the ABN sorbent provides greater stability and accuracy for atmospheric monitoring of cVMS. Implications of these improvements towards atmospheric fate processes will be discussed.
2020
Social-Environmental Analysis for the Management of Coastal Lagoons in North Africa
This study provides an overview of 11 lagoons in North Africa, from the Atlantic to the Eastern Mediterranean. Lagoons are complex, transitional, coastal zones providing valuable ecosystem services that contribute to the welfare of the human population. The main economic sectors in the lagoons included fishing, shellfish harvesting, and salt and sand extraction, as well as maritime transport. Economic sectors in the areas around the lagoons and in the watershed included agriculture, tourism, recreation, industrial, and urban development. Changes were also identified in land use from reclamation, changes in hydrology, changes in sedimentology from damming, inlet modifications, and coastal engineering. The human activities in and around the lagoons exert multiple pressures on these ecosystems and result in changes in the environment, affecting salinity, dissolved oxygen, and erosion; changes in the ecology, such as loss of biodiversity; and changes in the delivery of valuable ecosystem services. Loss of ecosystem services such as coastal protection and seafood affect human populations that live around the lagoons and depend on them for their livelihood. Adaptive management frameworks for social–ecological systems provide options that support decision makers with science-based knowledge to deliver sustainable development for ecosystems. The framework used to support the decision makers for environmental management of these 11 lagoons is Drivers–Activities–Pressures–State Change–Impact (on Welfare)–Responses (as Measures).
2020
We employ JRA-55 (Japanese 55-year Reanalysis), a recent second-generation global reanalysis providing data of high quality in the stratosphere, to examine whether a distinguishable effect of geomagnetic activity on Northern Hemisphere stratospheric temperatures can be detected. We focus on how the statistical significance of stratospheric temperature differences may be robustly assessed during years with high and low geomagnetic activity. Two problems must be overcome. The first is the temporal autocorrelation of the data, which is addressed with a correction of the t statistics by means of the estimate of the number of independent values in the series of correlated values. The second is the problem of multiplicity due to strong spatial autocorrelations, which is addressed by means of a false discovery rate (FDR) procedure. We find that the statistical tests fail to formally reject the null hypothesis, i.e. no significant response to geomagnetic activity can be found in the seasonal-mean Northern Hemisphere stratospheric temperature record.
2020
Risk governance of emerging technologies demonstrated in terms of its applicability to nanomaterials
Nanotechnologies have reached maturity and market penetration that require nano‐specific changes in legislation and harmonization among legislation domains, such as the amendments to REACH for nanomaterials (NMs) which came into force in 2020. Thus, an assessment of the components and regulatory boundaries of NMs risk governance is timely, alongside related methods and tools, as part of the global efforts to optimise nanosafety and integrate it into product design processes, via Safe(r)‐by‐Design (SbD) concepts. This paper provides an overview of the state‐of‐the‐art regarding risk governance of NMs and lays out the theoretical basis for the development and implementation of an effective, trustworthy and transparent risk governance framework for NMs. The proposed framework enables continuous integration of the evolving state of the science, leverages best practice from contiguous disciplines and facilitates responsive re‐thinking of nanosafety governance to meet future needs. To achieve and operationalise such framework, a science‐based Risk Governance Council (RGC) for NMs is being developed. The framework will provide a toolkit for independent NMs' risk governance and integrates needs and views of stakeholders. An extension of this framework to relevant advanced materials and emerging technologies is also envisaged, in view of future foundations of risk research in Europe and globally.
2020
Determining the Bio‐Based Carbon Content of Surfactants
In response to a mandate from the European Commission, the European Committee for Standardization (CEN) called on the technical committee CEN/TC 276 to develop a European standard (EN 17035) to define bio‐based surfactants and enable quantification of the bio‐based carbon content of surfactants based on radiocarbon analyses. This analytical approach was tested through directly contracted analyses and through a round robin procedure at commercial facilities in Europe. Initial results were unsatisfactory and further investigation identified issues surrounding the degree of homogenization in the samples. In general, the samples were only homogeneous at the gram level while the maximum quantity of material that could be introduced to the analytical process was at the milligram level. Having identified the root cause of the discrepancies between measured and expected results, new samples were sent to six European laboratories. The results were satisfactory indicating linearity and accuracy across the measurement range.
2020