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Rapid urbanization and uncontrolled industrial activities in developing countries have raised concerns about potentially toxic metal contamination of the environment. This study assessed the levels of potentially toxic elements in soil and airborne particulate matter in the Suame and Asafo areas in the Kumasi metropolis, characterized by a high concentration of auto mechanic workshops and residential settlements. X-ray fluorescence analysis and inductively coupled plasma-mass spectrometry were used to determine the metal concentrations in the samples. The results showed high concentrations of potentially toxic elements in the soil and air samples, indicating contamination from automotive activities. Metals such as Co, Ni, Pb, and Zn were found to be present at concentrations (13.42–6101.58 mg/kg and 14.15–11.74 mg/kg for Suame and Asafo respectively) that pose potential health risks to exposed populations. Mathematical models such as pollution indices were used to assess the extent of contamination and determine the potential sources of the metals - the automotive repairs. The findings highlight the urgent need for environmental management and remediation strategies to mitigate the health risks of exposure to potentially toxic elements in the Kumasi metropolis automotive hub.

The aim was two-fold: to characterise the risks of lead (Pb) in Agaricus bitorquis collected in the city of Leicester (England), and to evaluate its presence in urban topsoils. Pb was monitored by ICP-MS in twenty-two homogenised mushroom samples (caps and stipes) mineralised with HNO3/H2O2 [LoD = 0.872 mg/kg dry weight (dw)]. Moreover, 450 topsoil samples were collected from 18 urban parks across Leicester; Pb was also measured by ICP-MS after appropriate digestion (LoD = 0.698 mg/kg). Levels were significantly higher in the mushroom caps (p-value = 3 × 10−5); median and ranges are provided in mg/kg dw: 2.461 (1.806–6.664) vs. 1.579 (0.988–4.223). Concentrations were much higher than those reported in sixteen A. bisporus (median < 1.0 mg/kg DW) specifically cultivated in high-traffic areas in the inner city of Berlin, suggesting some contamination by Pb. All caps monitored exceeded the established maximum concentration limit for Pb in cultivated mushrooms in the European Union (3 mg/kg dw), in line with the high accumulative metal capability described in the literature for Agaricus spp. Although non-carcinogenic risks characterised for Pb were negligible in the monitored mushrooms, a high consumption of wild green edibles in Leicester's city should be limited as there are multiple additional sources of Pb and other metals, and they should be substituted by cultivated edibles where possible. [ABSTRACT FROM AUTHOR]

Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Polycyclic aromatic hydrocarbons are among persistent organic pollutants and incomplete combustion of hydrocarbons during petroleum processing activities may cause polycyclic aromatic hydrocarbons contamination in the surrounding area. For the first time in Morgah, Rawalpindi, Pakistan, three targeted polycyclic aromatic hydrocarbons i.e. naphthalene, phenanthrene, and pyrene were estimated from surroundings of an oil refinery. Samples were collected simultaneously in soil, water, and leaves of Melia azedarach L., a widely grown tree species in the sampling area, along different selected sites of main drainage coming out of the refinery. Among three polycyclic aromatic hydrocarbons, pyrene was observed in maximum concentration (24.31 mg/kg in soil) among all selected environmental media and studied compounds showed a dynamic behavior in context of accumulation at different sampling points. There was a significant effect of distance, from petroleum refining area on polycyclic aromatic hydrocarbons levels in soil, water and plant leaves. Our findings provide conclusive evidence that location of an oil refinery has attributed to high polycyclic aromatic hydrocarbons contamination in selected study area which can pose significant risk to general environment and to the public. [ABSTRACT FROM AUTHOR]

Rooftop cultivation of vegetables is considered as a potential food source for urban population. However, rooftop products in the urban area can be contaminated by different types of pollutants like toxic metals and polycyclic aromatic hydrocarbons (PAHs). The present study is the first that investigated the concentrations of toxic metals and PAHs in rooftop soils and vegetables grown in the urban and peri-urban areas of Bangladesh. Red amaranth and Spinach were selected for rooftop cultivation, and both soil and vegetable samples were collected and analyzed for determining the concentrations of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) as toxic metals, while naphthalene, fluorene, phenanthrene, anthracene, pyrene, benzo(a)anthracene, and chrysene as PAHs. The study observed that urban rooftop soil and vegetables were highly contaminated with toxic metals and PAHs as compared to peri-urban rooftop samples. The metal concentrations were found in order of Zn > Cu > Pb > Cd, however, Pb and Cd concentrations in urban vegetables exceeded the safe limit. On contrary, negligible concentrations of PAHs were detected in both urban and peri-urban rooftop vegetables. The values of health risk indices revealed that the concentrations of toxic metals and PAHs in urban rooftop vegetables would not pose any carcinogenic and non-carcinogenic health risks for adults and children and thus are considered to be safe for consumption. The findings of this study will provide scientific evidence to the policy makers and public administrations for urban agriculture based policy formulation as well as will encourage the city dwellers towards urban rooftop agricultural practices. [ABSTRACT FROM AUTHOR]

Lake sediments are natural receptors for a wide range of anthropogenic contaminants including organic matter and toxicants such as trace metals, polycyclic aromatic hydrocarbons, polychlorinated biphenyls that accumulate over time. This contamination can impact benthic communities, including microorganisms which play a crucial role in biogeochemical cycling and food-webs. The present survey aimed at exploring whether anthropogenic contamination, at a large lake scale, can influence the diversity, structure and functions of microbial communities associated to surface sediment, as well as their genetic potential for resistance to metals and antibiotics. Changes in the characteristics of these communities were assessed in surface sediments collected in Lake Geneva from eight sampling sites in October 2017 and May 2018. These sampling sites were characterized by a large concentration range of metal and organic compound contamination. Variation between the two sampling periods were very limited for all sampling sites and measured microbial parameters. In contrast, spatial variations were observed, with two sites being distinct from each other, and from the other six sites. Benthic communities from the most contaminated sampling site (Vidy Bay, near the city of Lausanne) were characterized by the lowest bacterial and archaeal diversity, a distinct community composition, the highest abundance of antibiotic resistance genes and functional (respiration, denitrification, methanogenesis, phosphatase, and beta-glucosidase) activity levels. The second sampling site which is highly influenced by inputs from the Rhône River, exhibited low levels of diversity, a distinct community composition, high abundance of antibiotic resistance genes and the highest bacterial abundance. Overall, our results suggest that local anthropogenic contamination, including organic matter and toxicants, is a major driver of the diversity and functioning of sediment-microbial communities in Lake Geneva. This highlights the need to consider benthic microbial communities and a suite of complementary ecotoxicological endpoints for more effective environmental risk assessments of contaminants in lake sediments. [ABSTRACT FROM AUTHOR]

We assessed the quality of Andes-Amazonia streams in Ecuador impacted by gold mining (GM), discharges from inefficient sewage network in urban areas (UA), wastes from fish farming (FF) and from non-functional landfill (LF) and other few threats (FT). We selected three lines of evidence (LOE) that were used separately and integrated into a index: water quality (WQI) and macroinvertebrate community (AAMBI) indices and phytotoxicity tests. Streams affected by UA and LF had the lowest scores to WQI and phytotoxicity, and by GM had the lowest scores to AAMBI. Macroinvertebrate absence in GM should be considered as a warning signal of long-term mining impacts in the area. The integrated LOE index showed that sites with identified threats had 30%–53% stream quality decline compared to FT sites. The use of the selected LOE seems to be a useful tools for long-term monitoring and evaluation of this sensitive aquatic ecosystem. [ABSTRACT FROM AUTHOR]

Two years of observations and interviews provided evidence of injustices as state officials ignored calls for monitoring by residents at a toxic waste site in Phoenix Arizona. When federal investigators arrived, they found toxic vapours exceeded regulatory levels in 17 homes and businesses out of the 77 locations sampled. That prompted a shift among the research team from observation to research intervention. Two public engagements were designed to perturb routine interactions between residents living on contaminated urban land and the government officials and corporate agents managing the environmental remediation efforts. The framing of techno-politics offers insights about who was excluded from decisions by non-elected technical experts and why they were excluded. Techno-politics, when used to focus on the urban-scale, demonstrates how historical decisions and values continue to influence contemporary actions and behaviours. Further, the concept of infrastructuring reveals what social, legal and technical mechanisms were built and how those modules were woven into the complex socio-technical system. In this way, it questions underlying assumptions, calls attention to short-term decisions, and highlights the lack experimentation and rigidity of the techno-political regime. It became evident that government officials and corporate agents believe the current technology can contain contamination for a thousand years. Thus, the obduracy of infrastructure came into relief and the intervention research made transparent the ways in which power and authority were used to maintain the status quo and perpetuate injustices. While alternative visions can theoretically counteract techno-political arrangements, it remains to be seen if transformative changes will occur. [ABSTRACT FROM AUTHOR]

This experiment was aimed at verifying the usefulness of phytoremediation using Short Rotation Coppice (SRC) in an urban Zn-contaminated site. Besides elemental uptake and reclamation, the SRC method was applied to evaluate the additional benefits of a green infrastructure. Nine different plants with rapid growth and large biomass production were selected: three Populus clones, three Salix hybrids, and three Robinia genotypes. Annual and biennial coppicing were evaluated. Poplar clones were more productive using annual coppicing, while Salix and Robinia produced higher biomass in blocks not coppiced. Poplar had the highest phytoextraction rate during the second year, with 1077 g/ha. Salix clones S1 and S3 extracted similar quantities using biennial coppicing. After two years, the bioavailable fraction of Zn decreased significantly using all species, from the 26% decrease of Robinia to the 36% decrease of Salix. The short rotation coppice method proved to be useful in an urban context, for both landscape and limiting the access to the contaminated area. Improving the biomass yield through the phytomanagement options (fertilization, irrigation, coppicing, etc.) could make SRC phytoremediation an economic and effective solution to manage urban contaminated areas, coupling the added values of biomass production to the landscape benefits. [ABSTRACT FROM AUTHOR]

The concentrations of Cu, Cr, Fe, Pb and Zn in thallus of three species of epiphytic lichens were determined: Flavopunctelia flaventior, Phaeophyscia orbicularis and Ramalina ecklonii, collected in three sectors of Talca city (Region of Maule, Chile), which have been exposed to different human activities. The first collection of samples was carried out by Pereira & Tapia. in 1999 and those results were compared with samples collected in 2016. Metal determinations were made by flame atomic absorption spectroscopy, considering the thallus of each lichen as representative sample for analysis. The methodological validation was carried out using certified reference material (SRM-1570). The highest levels of concentration in the three sectors and for the two sampling periods were for Fe > Zn > Pb > Cu > Cr > Cd. In 1999, the range of concentrations of the heavy metals in dry wet varied 335.5-1724 μg/g for iron (Fe); 40.7-209.5 μg/g for zinc (Zn); 10.4-64.2 μg/g for lead (Pb); 10-28.7 μg/g for copper (Cu); 0.6-4.8 μg/g for chromium and 0.1-0.4 μg/g for cadmium (Cd) while in 2016 the ranges were 1356.6-14280.4 μg/g for iron (Fe); 26.8-179.5 μg/g for zinc (Zn); 13.5-102.5 μg/g for lead (Pb); 7.9-36.2 μg/g for copper (Cu); 3.6-24.6 μg/g for chromium and not detected for cadmium (Cd). The samples collected in 2016 generally showed higher concentration levels of Fe, Cu, Cr and Pb than those collected in 1999, especially those corresponding to the central area of the city of Talca. According to the results, the species that accumulated more heavy metals were P. orbicularis followed by F. flaventior and last R. ecklonii. It can be concluded that foliose species are potentially better candidates to be used as long-term bioindicators than the fruticose species. The downtown sector of the city is the most polluted due to the presence of tannery industries and the increase of vehicular traffic that the city has had in the last two decades as a result of agricultural development and population growth.

This experiment was aimed at verifying the usefulness of phytoremediation using Short Rotation Coppice (SRC) in an urban Zn-contaminated site. Besides elemental uptake and reclamation, the SRC method was applied to evaluate the additional benefits of a green infrastructure. Nine different plants with rapid growth and large biomass production were selected: three Populus clones, three Salix hybrids, and three Robinia genotypes. Annual and biennial coppicing were evaluated. Poplar clones were more productive using annual coppicing, while Salix and Robinia produced higher biomass in blocks not coppiced. Poplar had the highest phytoextraction rate during the second year, with 1077 g/ha. Salix clones S1 and S3 extracted similar quantities using biennial coppicing. After two years, the bioavailable fraction of Zn decreased significantly using all species, from the 26% decrease of Robinia to the 36% decrease of Salix. The short rotation coppice method proved to be useful in an urban context, for both landscape and limiting the access to the contaminated area. Improving the biomass yield through the phytomanagement options (fertilization, irrigation, coppicing, etc.) could make SRC phytoremediation an economic and effective solution to manage urban contaminated areas, coupling the added values of biomass production to the landscape benefits.

Résumé Introduction Les mycétomes sont des affections cutanées infectieuses rares causées par des agents de nature fongique ou bactérienne. Elles siègent préférentiellement sur les extrémités. Nous rapportons ici un cas original de mycétome polyfistulisé chez un commerçant camerounais. Observation Une masse cutanée polyfistulisée était reçue au laboratoire d’anatomopathologie. Elle provenait d’un commerçant de 30 ans, sans antécédents particuliers, vivant à Yaoundé qui avait été vu en consultation pour une lésion de la plante du pied apparue plusieurs mois auparavant. Cette lésion, au départ se serait présentée sous la forme d’un nodule dur et indolore qui aurait par la suite fistulisé à la peau. Ces faits cliniques ne permettant d’évoquer un diagnostic certain, on avait procédé à une exérèse chirurgicale de cette masse et une analyse anatomopathologique avait été requise. L’examen histopathologique usuel couplé à des colorations spéciales avait révélé le diagnostic de mycétome d’étiologie fongique. Discussion Cette observation décrit un cas original de mycétome d’origine fongique non suspecté cliniquement, survenu chez un commerçant camerounais, vivant en milieu urbain et en dehors de toute zone d’endémicité de mycétome. Ce cas pour lequel le diagnostic était posé en histologie confirme l’apport indéniable de l’anatomopathologie au diagnostic de certitude. À notre connaissance, et selon les données disponibles, c’est la première fois qu’un mycétome soit décrit en milieu urbain au Cameroun. Summary Background Mycetoma are rare cutaneous affections caused by pathogens such as fungi or bacteria. They settle preferentially on limb extremities. We are going to talk about an original case of mycetoma in a young Cameroonian trader. Observation A cutaneous mass with multiple draining sinuses was received at the anatomy and cytopathology laboratory. That mass was from a 30-year-old male trader, with no particular medical history and living in Yaounde, who was received for a lesion at the sole of the foot, which appeared some months before. This lesion started like a tough and painless nodule, which later showed draining sinuses to the skin. The surgical resection of the tissue mass was performed. The histopathological analysis with special staining procedures, which was later on performed, revealed mycetoma caused by fungi. Discussion This observation describes an original case of fungal mycetoma, which occured in a Cameroonian trader living in an urban milieu away from any mycetoma endemic zone. This case confirms the undeniable or undisputable contribution of histopathology in diagnosis of certainty. To our knowledge and according to available data, it is a premiere to find a case of mycetoma described in an urban milieu in Cameroon. [ABSTRACT FROM AUTHOR]

Adsorption is a key water pollution remediation measure used to achieve stormwater quality improvement in Sustainable urban Drainage Systems (SuDS). The level of contamination of detained sediment within SuDS assets is not well documented, with published investigations limited to specific contaminant occurrence in ponds, wetlands or infiltration devices (bioretention cells) and generally focused on solute or suspended sediment. Guidance on contamination threshold levels and potential deposited sediment contamination information is not included in current UK SuDS design or maintenance guidance, primarily due to a lack of evidence and understanding. There is a need to understand possible deposited sediment contamination levels in SuDS, specifically in relation to sediment removal maintenance activities and potential impact on receiving waterways of conveyed sediment. Thus, the objective of the research presented herein was to identify what major elements and trace metals were observable in (the investigated) SuDS assets detained sediment, the concentration of these major elements and trace metals and whether they met/surpassed ecotoxicity or contaminated land thresholds. The research presented here provides evidence of investigated SuDS sediment major element and trace metal levels to help inform guidance and maintenance needs, and presents a new methodology to identify the general cause (anthropocentric land use) and extent of detained SuDS fine urban sediment contamination through use of a contamination matrix. [ABSTRACT FROM AUTHOR]

Copyright of Revista Luna Azul is the property of Universidad de Caldas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The anthropogenic emissions of Pt to the environment have increased significantly over the past decades, especially after the introduction of the catalytic converters in motor vehicles. In order to check whether this is affecting the levels of this trace metal on living organisms, time-series analysis of freeze-dried soft tissue material of wild mussels ( Mytilus galloprovincialis ) covering the period from 1991 to 2001 and collected at an urban beach in the city of Vigo (NW Iberian Peninsula) was conducted. Concentrations ranged from 0.30 to 0.68 ng g − 1 with an average concentration of 0.47 ± 0.10 ng g − 1 ( n = 21); these concentrations were higher than those obtained for samples collected at a control location away from anthropogenic pressure (0.31 ± 0.10 ng g − 1 ; n = 5). Platinum concentrations followed a statistically significant temporal trend (at the 0.020 level), and the excess of Pt in mussels over the 1991–2011 period compared to the control location were correlated with the European Pt autocatalyst demand ( p = 0.0006) and, especially, the car sales in Spain ( p = 0.0001). A bioaccumulation factor of ~ 5 · 10 3 was derived, which is greater than those previously calculated for Pt from exposure experiments, but 1–2 orders of magnitude lower than other trace elements (e.g. Zn, Cu, Pb, Cd). [ABSTRACT FROM AUTHOR]

Abstract: The Water Framework Directive requires the development of biological tools which can act as early-warning indicators of a sudden increase (accidental pollution) or decrease (recovery due to prevention) of the chemical status of aquatic systems. River biofilms, which respond quickly to modifications of environmental parameters and also play a key part in the functioning of aquatic ecosystems, are therefore good candidates to monitor an increase or a decrease of water pollution. In the present study, we investigated the biological response of biofilms transplanted either upstream (recovery) or downstream (deterioration of exposure levels) the urban area of Paris (France). Both modifications of Cu community tolerance levels and of global bacterial and eukaryotic community structure using automated ribosomal intergenic spacer analysis (ARISA) fingerprints were examined 15 and 30 days after the transplantation. Cu tolerance levels of the heterotrophic component of biofilms were assessed using a short-term toxicity test based on β-glucosidase (heterotrophic) activity. Cu tolerance increased for biofilms transplanted upstream to downstream Paris (5-fold increase on day 30) and conversely decreased for biofilms transplanted downstream to upstream (8-fold decrease on day 30). ARISA fingerprints revealed that bacterial and eukaryotic community structures of transplanted biofilms were closer to the structures of biofilms from the transplantation sites (or sites with similar contamination levels) than to biofilms from their sites of origin. Statistical analysis of the data confirmed that the key factor explaining biofilm Cu tolerance levels is the sampling site and not the site of origin. It also showed that Cu tolerance levels are related to the global urban contamination (both metals and nutrients). The study shows that biofilms adapt fast to modifications of their surroundings. In particular, community tolerance varies quickly and reflects the new exposure levels only 15 days after transplantation. Those results support the use of biofilms as reliable early-warning indicators of diffuse urban contamination. [Copyright &y& Elsevier]

The feasibility of reducing children’s exposure to lead (Pb) polluted soil in New Orleans is tested. Childcare centers (median = 48 children) are often located in former residences. The extent of soil Pb was determined by selecting centers in both the core and outlying areas. The initial 558 mg/kg median soil Pb (range 14–3692 mg/kg) decreased to median 4.1 mg/kg (range 2.2–26.1 mg/kg) after intervention with geotextile covered by 15 cm of river alluvium. Pb loading decreased from a median of 4887 μg/m2 (454 μg/ft2) range 603–56650 μg/m2 (56–5263 μg/ft2) to a median of 398 μg/m2 (37 μg/ft2) range 86–980 μg/m2 (8–91 μg/ft2). Multi-Response Permutation Procedures indicate similar (P-values = 0.160–0.231) soil Pb at childcare centers compared to soil Pb of nearby residential communities. At ∼$100 per child, soil Pb and surface loading were reduced within hours, advancing an upstream intervention conceptualization about Pb exposure prevention. [Copyright &y& Elsevier]

Abstract: Isolated mollusk shells and crustacean exoskeletons adsorb from waters almost twice their weight of Pb in a few minutes. Likewise, the chitin-based sorbents of animal and fungal origin adsorb U and transuranium elements: some are manufactured commercially in a form suitable for high flow-rates. Supported viable Trichoderma harzianum is quite effective in collecting microcrystals of U oxides. Chitosan as well can induce deposition of mixed U oxides, to the point that the final material contains a prevailing inorganic component. Metal-reducing bacteria also offer good performances. These data are exploitable for preventing pollution in civilian operations: the pollution case of Colonie, NY, is discussed in the light of the high toxicity of uranium. The disappointing results of the programs aimed at the collection of uranium from seawater with the aid of synthetic poly(amidoamine) induce to envisage that chitin/chitosan-bearing materials might be involved in the future exploitation of the marine uranium resources. [ABSTRACT FROM AUTHOR]

This study describes the biological importance of Guajará Bay (Belém, Pará, Brazil) for fish fauna and presents a diagnosis of water quality in the main channel and creeks, using the icthyofauna as an ecological indicator. A total of 567 individuals from 40 species were identified. About 58% of these use Guajará Bay as a nursery ground, 49 and 81% use the bay as a breeding and feeding ground, respectively. There were no significant differences between environments as measured by the diversity index; however, fish relative abundance (catch per unit of effort) was greater in the creeks than in the main channel. A significant difference was detected in the fish fauna inhabiting the main channel compared with the creeks. In the main channel, icthyofauna significantly differed during December relative to other months. [ABSTRACT FROM AUTHOR]

A regional policy of new towns development is proposed in order to obtain a better quality of life, a more rational use of energy, water and soil resources and alleviation of population pressure in the large cities, lower costs of contamination management and mitigation of impacts of urban population on ecosystems. Geographic, historic, social and economic obstacles in contamination management are noted and the case of the capital is analyzed. Engineering roles in obtaining sustainable cities are outlined. Priority in the development of new towns in the Caribe and Orinoquía is recommended. [ABSTRACT FROM AUTHOR]

Abstract: The impact on a population from an event resulting in dispersal and deposition of radionuclides in an urban area could be significant, in terms of both the number of people affected and the economic costs of recovery. The use of computer models for assessment of urban contamination situations and remedial options enables the evaluation of a variety of situations or alternative recovery strategies in contexts of preparedness or decision-making. At present a number of models and modelling approaches are available for different purposes. This paper summarizes the available modelling approaches, approaches for modelling countermeasure effectiveness, and current sources of information on parameters related to countermeasure effectiveness. Countermeasure information must be applied with careful thought as to its applicability for the specific situation being modelled. Much of the current information base comes from the Chernobyl experience and would not be applicable for all types of situations. [Copyright &y& Elsevier]

Abstract: This study reports the degree of heavy metal pollution (Cr, Cu, Ni, Pb, Zn and V) in 135 urban topsoil samples from the metropolitan area of Mexico City. Pollution indices (PI) were calculated to identify the metal accumulation with respect to the background values. The levels of heavy metals in the analyzed samples show a wide range of variation. Lead, Zn and Cu are the elements most enriched in the analyzed area, presenting pollution indexes of up to 23.8, 21.6 and 12.4, respectively. Geochemical maps were produced to assess the spatial distribution of pollution index. It is concluded that emissions from vehicles may be the major source of Pb urban contamination; furthermore, other small or large factories are possible sources for soil pollution (Cu, Zn). The concentration of Cr, Ni, and V in most of the analyzed samples do not appear to reach pollution levels. The assessment of the soil environmental quality in the metropolitan area Mexico City in terms of PI can be used as the basis for a regular monitoring program for implementing suitable pollution control measures. [Copyright &y& Elsevier]

Abstract: The Urban Remediation Working Group of the International Atomic Energy Agency''s EMRAS (Environmental Modelling for Radiation Safety) program was organized to address issues of remediation assessment modelling for urban areas contaminated with dispersed radionuclides. The present paper describes the second of two modelling exercises. This exercise was based on a hypothetical dispersal of radioactivity in an urban area from a radiological dispersal device, with reference surface contamination at selected sites used as the primary input information. Modelling endpoints for the exercise included radionuclide concentrations and external dose rates at specified locations, contributions to the dose rates from individual surfaces, and annual and cumulative external doses to specified reference individuals. Model predictions were performed for a “no action” situation (with no remedial measures) and for selected countermeasures. The exercise provided an opportunity for comparison of three modelling approaches, as well as a comparison of the predicted effectiveness of various countermeasures in terms of their short-term and long-term effects on predicted doses to humans. [Copyright &y& Elsevier]

Abstract: The Urban Remediation Working Group of the International Atomic Energy Agency''s EMRAS (Environmental Modelling for Radiation Safety) program was organized to address issues of remediation assessment modelling for urban areas contaminated with dispersed radionuclides. The present paper describes the first of two modelling exercises, which was based on Chernobyl fallout data in the town of Pripyat, Ukraine. Modelling endpoints for the exercise included radionuclide concentrations and external dose rates at specified locations, contributions to the dose rates from individual surfaces and radionuclides, and annual and cumulative external doses to specified reference individuals. Model predictions were performed for a “no action” situation (with no remedial measures) and for selected countermeasures. The exercise provided a valuable opportunity to compare modelling approaches and parameter values, as well as to compare the predicted effectiveness of various countermeasures with respect to short-term and long-term reduction of predicted doses to people. [Copyright &y& Elsevier]

Abstract: The Urban Remediation Working Group of the International Atomic Energy Agency''s Environmental Modelling for Radiation Safety (EMRAS) programme was established to improve modelling and assessment capabilities for radioactively contaminated urban situations, including the effects of countermeasures. An example of the Working Group''s activities is an exercise based on Chernobyl fallout data in Ukraine, which has provided an opportunity to compare predictions among several models and with available measurements, to discuss reasons for discrepancies, and to identify areas where additional information would be helpful. [Copyright &y& Elsevier]

In order to evaluate the historical impact of urban stormwater runoff on a lacustrine environment, eight sediment cores were collected in October 2006 in Lake Bourget (Savoie, France). Sediment samples were analysed for polycyclic aromatic hydrocarbons (PAH) and polychlorobyphenyls (PCB) in order to correlate the vertical profiles of contamination and the evolution of the urbanisation on the watershed for the last 100 years. Overall, we observe that vertical profiles of PCB and PAH concentrations in Lake Bourget are showing a downward trend, probably resulting from the pollution control measures. Concentrations of PCB and PAH measured in surface sediments are approximately 5-10 fold less than maximal concentrations found in the cores. Maximal PAH concentrations were found at the bottom of the cores (~40 cm) which approximately correspond to the beginning of the 20th century. Maximal PCB concentrations measured in cores L5 and L6 are respectively 850 and 790 μg/g dw (dryweight). The peak of PCB corresponds to the maximum of PCB production and consumption in the 1970s. In surface sediments total PCB concentrations range between 47 and 79 μg/kg dw. Those concentrations are particularly high compared to other values measured in lake sediments and highlight the problem of a local source of PCB contamination in the watershed. General trends were observed, yet the part of urban stormwater runoff in the total contamination could not be determined. [ABSTRACT FROM AUTHOR]

Recent investigations in Russia have emphasised the significance of dose contributions from contamination on urban streets and roof pavings, and, typically to a lesser extent, walls in the urban environment. The crucial factor determining the magnitude of these contributions is the retention of the contamination by the different types of urban surface. Since the Chernobyl accident, a series of long-term field studies has been carried out on urban streets, walls and roofs, to examine the weathering processes of 137Cs on the various surface types. The derived time-functions are applied to estimate resultant long-term doses to inhabitants of an urban centre. The paper highlights the effect on caesium retention of surface material characteristics. [Copyright &y& Elsevier]

This study aims to evaluate the impacts of the activation of a hypothetical radiological dispersal device (RDD) on the urban critical infrastructure (health facilities and public transport). A densely populated urban region was chosen as a scenery. Additionally, the influence of local environmental factors in the post-detonation process was verified. The source term was Cs-137 due to its mobility in the environment and relative ease of access. The approach used for the evaluation of the consequences was a computer simulation by Gaussian modeling. The HotSpot Health Physics Codes software was applied in conjunction with the RESRAD-RDD software. The results suggest that there is a strong influence of the local atmospheric stability classes (Pasquill-Gifford classes) on both the total equivalent effective dose (TEDE) and soil contamination. Consequently, the impacts on critical urban infrastructure follow the same trend. The method used for comparing the simulated and reference limits was the proportional ratio. All calculated values for radioactive contamination were divided by the reference value adopted by the RESRAD-RDD model for urban critical infrastructure. The results indicate that the information compiled is useful to support the decision-making process, although it is not sufficient to provide care and support for longer periods than those considered in the initial response phase. • Urban critical infrastructure are severely impacted by the RDD. • Atmospheric stability strongly influences TEDE in the first hours. • Codes approaching together may provide better support to decision. [ABSTRACT FROM AUTHOR]

Data on chlorophenoxy herbicides (CPHs) in drinking water from China are scarce. This study was designed to describe the occurrence of CPHs in drinking water in China. In June 2019, drinking water samples including 789 tap water and 95 groundwater samples were collected from 31 provinces in mainland China and Hong Kong. Raw source, treated, and tap water samples (n = 20, 20, and 170, respectively) in Wuhan, Central China were also analyzed. 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methyl-4-chlorophenoxyacetic acid (MCPA) were found in 71.2% and 74.9% of the samples nationwide, respectively. The cumulative concentration of CPHs (ΣCPHs) in tap water in China was up to 125 ng/L (median: 1.38 ng/L), and regional variations were found for ΣCPHs. The highest median ΣCPHs (3.95 ng/L) was found in Northeast China, followed by Central (3.40), South (2.71), East (2.43), Southwest (1.58), North (0.42), and Northwest China (0.30). The median ΣCPHs in groundwater was approximately five times lower than that in tap water. In addition, ΣCPHs were found in all the raw source water samples collected in Wuhan, Central China (median: 6.69 ng/L, range: 2.66–43.1 ng/L). The removal of 2,4-D and MCPA during conventional drinking water treatment was not efficient, removing approximately 0.91% and 17.4%, respectively. In a water plant with advanced treatment, they were efficiently removed. Seasonal variations were found in ΣCPHs in tap water from Wuhan, with the highest found in July (median: 21.2 ng/L), and the lowest in October (1.96 ng/L). The intake of CPHs via water ingestion was estimated as below 5 ng/kg-bw/day, much lower than the reference doses for 2,4-D (5 μg/kg-bw/day) and MCPA (4 μg/kg-bw/day). This is the first study to demonstrate the fate of CPHs during drinking water treatment and seasonal variations of CPHs in water from Wuhan, China. Moreover, this study provides an overview of ΣCPHs in tap water for many areas in China. Unlabelled Image • The highest median ΣCPHs was found in Northeast China. • MCPA was higher than 2,4-D in water from Wuhan and many other cities. • The highest ΣCPHs were observed in July, and the lowest in October. • Higher ΣCPHs were found in surface water derived tap water than in groundwater. [ABSTRACT FROM AUTHOR]

In the present work, a sampling grid of the urban core of the city of Murcia (South East Spain) was designed in order to analyze street dust, focusing on the contents of the heavy metals Cd, Cr, Cu, Ni, Pb, and Zn and their relationships with the color of the sample, the traffic pattern, and the location where they were sampled (sidewalks, ledges, and roads). The characterization of the samples was carried out by X-ray diffraction and scanning electron microscopy, whereas the heavy metals were extracted by acid digestion and determined by inductively coupled plasma mass spectrometry. The concentration (mg/kg) in urban dust of the city of Murcia was highest for Zn (653), followed by Cu (201) > Pb (177) > Cr (117) > Ni (51) >> Cd (0.5). The color expounded statistically significant differences with regard to the heavy metals, including the pollutant load. The same pattern was found when the classification variable was the traffic intensity, except in the case of Ni. The areas with a higher risk of contamination by heavy metals in the urban dust are the ledges of narrow city center streets with moderate traffic, where Zn and Pb seem to accumulate most greatly. [ABSTRACT FROM AUTHOR]