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Behavioural ecotoxicology, an “early warning” signal to assess environmental quality Полный текст
2011
Hellou, Jocelyne
BACKGROUND: In this review, the position of behavioural ecotoxicology within the available means to assess the status of marine environments is described as filling the gap for the needed “early warning” signals. A few examples of studies performed since the 1960s are discussed to highlight the sensitivity of these approaches in investigating the effects of chemicals, including priority pollutants and emerging contaminants, relative to conventional toxicity tests measuring survival. DISCUSSION: The advantage of the behavioural response is due to the integration of biochemical and physiological processes that reflect changes at higher levels of organisation with ecological relevance. Avoidance often represents a behavioural symptom easily detected in many animals exposed to contaminants and would be a useful test to explore more widely. This rapid response would reflect a defence mechanism protective against further exposure and the potential development of more pronounced deleterious effects, whilst in some cases, escape could lead to the relocation of a species with negative consequences. An investigation of the avoidance behaviour of mud shrimp, Corophium volutator, along with the chemical analyses of sediments and amphipods to assess the quality of harbour sediments is summarised. The body burden of the amphipods was 1,000 times lower than the one associated with narcosis, emphasizing the sensitivity of this endpoint. The application of this acute toxicity test is briefly compared to additional work that involved intertidal mussels collected in the field. CONCLUSIONS: Recent research undertaken with mud snails, Ilyanassa obsoleta, and harbour sediments confirmed the usefulness of the escape behaviour as an assessment tool. However, the limits of the state of knowledge regarding the fate of contaminants in species with the ability to metabolise contaminants is further discussed along with directions to be pursued to address questions arising from the reviewed literature.
Показать больше [+] Меньше [-]Exploring the metal phytoremediation potential of three Populus alba L. clones using an in vitro screening Полный текст
2011
Di Lonardo, Sara | Capuana, Maurizio | Arnetoli, Miluscia | Gabbrielli, Roberto | Gonnelli, Cristina
PURPOSE: This work was planned for providing a useful screening tool for the selection of Populus alba clones suitable for phytoremediation techniques. To this aim, we investigated variation in arsenic, cadmium, copper, and zinc tolerance, accumulation and translocation in three poplar clones through an in vitro screening. Poplars have been widely proposed for phytoremediation, as they are adaptable to grow on contaminated areas and able to accumulate metals. The investigation of possible differences among poplar clones in metal tolerance and accumulation deserves to be deeply studied and exploited for the selection of the more suitable tool for phytoremediation purposes. METHODS: In vitro multiplied microshoots of a commercial and two autochthonous P. alba clones were subcultured on hormone-free WPM medium for 1 month and then transferred for 2 weeks onto media containing different concentrations of the metals investigated. At the end of the treatments, plantlets were sampled, weighed, and mineralised by wet ashing. Metal concentrations were determined by ICP-OES. RESULTS: For the metal concentration used in the experiments, our clones of P. alba showed variation in metal tolerance, metal accumulation and content. The fast-growing commercial clone, even if rarely showing the highest plant metal concentration, displayed the highest metal content, suggesting biomass production as the key factor in evaluating the phytoextraction capacity of P. alba clones for the metals studied. CONCLUSIONS: Data demonstrated that in vitro screening of cuttings represents a valuable way of assessing the ability of different poplar clones to take up, tolerate and survive metal stress.
Показать больше [+] Меньше [-]Do metal concentrations in moss from the Zackenberg area, Northeast Greenland, provide a baseline for monitoring? Полный текст
2011
Zechmeister, Harald G. | Dullinger, Stefan | Koellensperger, Gunda | Ertl, Siegrun | Lettner, Christian | Reiter, Karl
PURPOSE: This study aims at evaluating (a) whether concentrations of a suite of elements in mosses sampled in the arctic region around Zackenberg reflect background concentrations useful for estimating pollution levels in industrialized parts of the northern hemisphere as is attempted, e.g. in the framework of the UNECE ICP Vegetation monitoring programme, and (b) whether there are any influences from Zackenberg research station detectable in these concentrations. METHODS: Two moss species were sampled according to guidelines used in the UNECE ICP Vegetation programme. Samples were analysed for ¹⁹⁵Pt at low resolution, ²⁷Al, ⁵²Cr, ⁶⁵Cu, ⁶⁶Zn, ⁹⁵Mo, ¹¹¹Cd, ¹¹⁸Sn, ¹²¹Sb and ²⁰⁸Pb at medium resolution and ⁷⁵As at high resolution on an Element 2 inductively coupled plasma sector field mass spectrometer. RESULTS: Except for Al, As and Cr, data from Zackenberg showed significantly lower mean element concentrations than those reported in comparable studies from all over the world including those from other Arctic environments. Minimum concentrations in Zackenberg mosses were consistently below all values reported so far for all elements analysed. The results of a PCA suggested only a slight impact from Zackenberg research station on concentrations of Cd, Mo and Zn in moss. CONCLUSIONS: We conclude that the sites in Zackenberg can be considered true background sites providing baseline concentrations of at least eight elements for comparable monitoring studies.
Показать больше [+] Меньше [-]Still present after all these years: persistence plus potential toxicity raise questions about the use of atrazine Полный текст
2011
As one of the worlds' most heavily applied herbicides, atrazine is still a matter of controversy. Since it is regularly found in ground and drinking water, as well as in sea water and the ice of remote areas, it has become the subject of continuous concern due to its potential endocrine and carcinogenic activity. Current findings prove long-held suspicions that this compound persists for decades in soil. Due to the high amount applied annually all over the world, the soil burden of this compound is considered to be tremendous, representing a potential long-term threat to the environment. The persistence of chemicals such as atrazine has long been underestimated: Do we need to reconsider the environmental risk?
Показать больше [+] Меньше [-]Evaluating threats to an endangered species by proxy: air pollution as threat to the blue swallow (Hirundo atrocaerulea) in South Africa Полный текст
2011
Kylin, Henrik | Bouwman, Henk | Evans, Steven W
Background, aim, and scope The blue swallow (Hirundo atrocaerulea) is one of the most threatened bird species in southern Africa. Among terrestrial birds, its plumage is known to be the most water repellent, an adaptation to foraging on the wing in dense fog. Despite this unique adaptation, the nesting success of the blue swallow at the Blue Swallow Natural Heritage Site (BSNHS) is lower during years with high incidence of fog. As the phenomenon is not observed at other nesting sites, we hypothesized that this is due to changes in the air chemistry at the BSNHS. In the immediate proximity of the BSNHS, plantations of exotic trees (e.g., pines and eucalypts), rich in volatile organic compounds (VOCs), are dominant features. In addition, air pollution from the Johannesburg area is transported with the surface winds and mix with VOCs released from exotic trees. Together with the high humidity and high elevation, these conditions may result in the formation of sulphonates. Sulphonates are strong detergents, and the presence of these in the fog could lead to decreased water repellence of the plumage. This study was performed in order to determine the occurrence and distribution of sulphonates in the BSNHS and to compare these with sulphonates formed in other locations in South Africa. Because the blue swallow is endangered, pine needles were used as proxy to detect formation of sulphonates. Methods We sampled pine needles with different exposure to air pollutants, in climates with different humidity, and at different elevation and analyzed these for sulphonates using mass spectrometry. Results Pine needles from high elevations and the BSNHS, with high humidity, and exposure to air pollution contained significantly higher concentrations of sulphonates than pine needles from low elevations or from high elevations with a dryer climate or a different combination of air pollutants. Conclusions These findings lead to two conclusions. First, the occurrence and distribution of sulphonates may be explained by chemical reactions between sulphur dioxide and organic compounds in the humid air induced by ultraviolet radiation. Second, elevated concentrations of sulphonates in the fog could affect the water repellence of the blue swallow plumage, possibly decreasing their capacity to forage in the fog. We cannot prove conclusively that this is the reason why the number of blue swallows at the BSNHS has decreased dramatically, but for endangered species, we may have to rely on proxies to draw conclusions about outside threats. All such information should be valuable in devising protection plans for species under threat. Recommendations and perspectives The use of proxies to elucidate threats to endangered species should be evaluated in a broad scale. The mist-belt habitat in general is threatened by many human activities. These findings indicate that air pollution and the proximity of volatile organic compound (VOC) sources close to mist-belt habitat refuges may be an unrecognised conservation threat to the animals inhabiting them.
Показать больше [+] Меньше [-]Incorporation of in silico biodegradability screening in early drug development--a feasible approach Полный текст
2011
Steger-Hartmann, Thomas | Lange, Reinhard | Heuck, Klaus
Introduction The concentration of a pharmaceutical found in the environment is determined by the amount used by the patient, the excretion and metabolism pattern, and eventually by its persistence. Biological degradation or persistence of a pharmaceutical is experimentally tested rather late in the development of a pharmaceutical, often shortly before submission of the dossier to regulatory authorities. Materials and methods To investigate whether the aspect of persistence of a compound could be assessed early during drug development, we investigated whether biodegradation of pharmaceuticals could be predicted with the help of in silico tools. To assess the value of in silico prediction, we collected results for the OECD 301 degradation test (“ready biodegradability”) of 42 drugs or drug synthesis intermediates and compared them to the prediction of the in silico tool BIOWIN. Results and discussion Of these compounds, 38 were predictable with BIOWIN, which is a module of the Estimation Programs Interface (EPI) Suite™ provided by the US EPA. The program failed to predict the two drugs which proved to be readily biodegradable in the degradation tests. On the other hand, BIOWIN predicted two compounds to be readily biodegradable which, however, proved to be persistent in the test setting. Conclusion The comparison of experimental data with the predicted one resulted in a specificity of 94% and a sensitivity of 0%. The results of this study do not indicate that application of the biodegradation prediction tool BIOWIN is a feasible approach to assess the ready biodegradability during early drug development.
Показать больше [+] Меньше [-]Applications of polychlorinated biphenyls Полный текст
2011
Erickson, Mitchell D | Kaley, Robert G II
Background, aim, and scope In the 50 years or so that polychlorinated biphenyls (PCBs) were manufactured in the USA and elsewhere, they were widely used in numerous applications because of their desirable properties. The purpose of this paper is to review and summarize in one place the factual information about the uses of PCBs, as well as to correct some misconceptions that have arisen over the years. The focus is on applications in the USA for which there is ample documentation. However, use patterns were probably similar worldwide. Materials and methods Review. Results PCBs were used primarily as electrical insulating fluids in capacitors and transformers and also as hydraulic, heat transfer, and lubricating fluids. PCBs were blended with other chemicals as plasticizers and fire retardants and used in a range of products including caulks, adhesives, plastics, and carbonless copy paper. In the USA, PCBs were manufactured from 1929 through mid-1977, although many products remained in service for decades after the manufacture of PCBs was terminated. This article reviews the historic uses of PCBs in the USA and discusses, where possible, the relative sales volumes. Especially with smaller volume, military, and third-party uses, documenting a use and/or differentiating between a commercial use and an experimental test batch is not possible. Discussion A major contribution of this paper is to differentiate reported commercial applications of PCBs that can be documented from those which cannot. Undocumented uses may include actual minor uses as well as reported applications that are unlikely ever to have been commercialized.
Показать больше [+] Меньше [-]Vertical transport of ozone and CO during super cyclones in the Bay of Bengal as detected by Tropospheric Emission Spectrometer Полный текст
2011
Fadnavis, S | Beig, G | Buchunde, P | Ghude, Sachin D | Krishnamurti, T. N
Vertical profiles of carbon monoxide (CO) and ozone retrieved from Tropospheric Emission Spectrometer have been analyzed during two super cyclone systems Mala and Sidr. Super cyclones Mala and Sidr traversed the Bay of Bengal (BOB) region on April 24-29, 2006 and November 12-16, 2007 respectively. The CO and ozone plume is observed as a strong enhancement of these pollutants in the upper troposphere over the BOB, indicating deep convective transport. Longitude-height cross-section of these pollutants shows vertical transport to the upper troposphere. CO mixing ratio ~90 ppb is observed near the 146-mb level during the cyclone Mala and near 316 mb during the cyclone Sidr. Ozone mixing ratio ~60-100 ppb is observed near the 316-mb level during both the cyclones. Analysis of National Centers for Environmental Prediction (NCEP) reanalysis vertical winds (omega) confirms vertical transport in the BOB.
Показать больше [+] Меньше [-]Effective dose estimation and lifetime cancer mortality risk assessment from exposure to Chernobyl ¹³⁷Cs on the territory of Belgrade City and the region of Vojvodina, Serbia Полный текст
2011
Spasić-Jokić, Vesna | Župunski, Ljubica | Janković, Ljiljana | Gordanić, Vojin
Purpose The purpose of this paper is to determine the activity concentrations of radionuclide ¹³⁷Cs in soil samples on the territory of Belgrade and the province of Vojvodina. Also, the lifetime cancer mortality risk from external exposure during 1 year is assessed, and the effective dose is estimated. Methods Eighty eight soil samples were collected from 30 uncultivated locations in Belgrade, and 30 soil samples were collected from 10 locations in the province of Vojvodina. Activity concentrations were measured using an HPGe detector. Using dose conversion factors taken from “EPA Federal Guidance Report 12,” annual effective doses from external sources were estimated. The lifetime cancer mortality risk was assessed using cancer risk coefficients taken from “EPA Federal Guidance Report 13.” Results Activity concentrations of ¹³⁷Cs for the territory of Belgrade are in the range of 2.07-89.1 Bq/kg with a mean value of 23.77 Bq/kg; the estimated annual effective doses are in the range of 0.41-17.5 nSv with a mean value of 4.67 nSv, and assessed lifetime cancer mortality risks, normalized on 100,000 inhabitants, are in the range 0.2-9.5 × 10⁻⁵ with a mean value 2.5 × 10⁻⁵. Activity concentrations of ¹³⁷Cs for the province of Vojvodina are in the range of 2.73-18.9 Bq/kg with a mean value of 8.57 Bq/kg; estimated annual effective doses are in the range of 0.54-3.71 nSv with a mean value of 1.68 nSv, and assessed lifetime cancer mortality risks, normalized on 100,000 inhabitants, are in the range of 0.3-2.0 × 10⁻⁵ with a mean value 0.9 × 10⁻⁵. Conclusion Receiving doses are low from ¹³⁷Cs radionuclides occurring in soil, according to the linear no-threshold approach; the risk for cancer development exists but is very small.
Показать больше [+] Меньше [-]PM₁₀ source apportionment in the surroundings of the San Vicente del Raspeig cement plant complex in southeastern Spain Полный текст
2011
Yubero, Eduardo | Carratalá, Adoración | Crespo, Javier | Nicolas, Jose | Santacatalina, Milagros | Nava, Silvia | Lucarelli, Franco | Chiari, Massimo
INTRODUCTION: The concentrations of trace metals, ionic species, and carbonaceous components in PM₁₀ (particulate matter with aerodynamic diameters smaller than 10 µm) were measured from samples collected near an industrial complex, primarily composed of cement plants, in southeastern Spain, from September 2005 to August 2006. MATERIALS AND METHODS: Positive matrix factorization and conditional probability function were applied to this data set to identify different types of sources. RESULTS: Six significant sources were identified: crustal matter, traffic, aged sea salt, industrial emissions, secondary aerosol, and sea salt. The difficulty of separating anthropogenic sources from those of natural origin is highlighted in this study; in particular, the crustal source can be connected with both natural (African outbreaks, wind resuspension) and man-made emissions, like fugitive emissions in an industrial environment.
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