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Chemical and toxicological characterisation of anticancer drugs in hospital and municipal wastewaters from Slovenia and Spain Texte intégral
2016
Isidori, Marina | Lavorgna, Margherita | Russo, Chiara | Kundi, M. (Michael) | Žegura, Bojana | Novak, Matjaž | Filipič, Metka | Mišík, Miroslav | Knasmueller, Siegfried | de Alda, Miren López | Barceló, Damià | Žonja, Božo | Česen, Marjeta | Ščančar, Janez | Kosjek, Tina | Heath, Ester
Anticancer drugs are continuously released into hospital and urban wastewaters, where they, most commonly, undergo conventional treatment in wastewater treatment plants (WWTPs). Wastewaters contain complex mixtures of substances including parent compounds, their metabolites and transformation products (TPs). In this study, samples of hospital effluents and WWTP influents and effluents from Slovenia and Spain were analyzed for twenty-two selected anticancer drugs, their metabolites and transformation products. Acute and chronic toxicity tests were performed on the crustacean Ceriodaphnia dubia, genotoxicity was determined with Tradescantia and Allium cepa micronucleus (MN) assays and in vitro comet assay in zebrafish (Danio rerio) liver cell line (ZFL cells). Sixty of the two hundred-twenty determinations revealed detectable levels of anticancer drug residues. Among the targeted compounds, platinum based were most frequently detected (90%). Furthermore, erlotinib was detected in 80%, cyclophosphamide and tamoxifen in 70% and methotrexate in 60% of the samples. Seven of ten samples were toxic to C. dubia after acute exposure, whereas after chronic exposure all samples reduced reproduction of C. dubia at high sample dilutions. Allium cepa proved insensitive to the potential genotoxicity of the tested samples, while in Tradescantia increased MN frequencies were induced by a hospital effluent and WWTP influents. In ZFL comet assay all but one sample induced a significant increase of DNA strand breaks. Correlations of chemotherapeutics or their TPs were detected for all bioassays except for Allium cepa genotoxicity test, however for each test the highest correlations were found for different substances indicating differential sensitivities of the test organisms.
Afficher plus [+] Moins [-]Mutielemental concentration and physiological responses of Lavandula pedunculata growing in soils developed on different mine wastes Texte intégral
2016
Santos, Erika S. | Abreu, Maria Manuela | Saraiva, Jorge A.
This study aimed to: i) evaluate the accumulation and translocation patterns of potentially hazardous elements into the Lavandula pedunculata and their influence in the concentrations of nutrients; and ii) compare some physiological responses associated with oxidative stress (concentration of chlorophylls (Chla, Chlb and total), carotenoids, and total protein) and several components involved in tolerance mechanisms (concentrations of proline and acid-soluble thiols and total/specific activity of catalase (CAT) and superoxide dismutase (SOD)), in plants growing in soils with a multielemental contamination and non-contaminated. Composite samples of soils, developed on mine wastes and/or host rocks, and L. pedunculata (roots and shoots) were collected in São Domingos mine (SE of Portugal) and in a reference area with non-contaminated soils, Corte do Pinto, with the same climatic conditions.São Domingos soils had high total concentrations of several hazardous elements (e.g. As and Pb) but their available fractions were small (mainly <5.8 % of the total). Translocation behaviour of elements was not clear according to the physiological importance of the elements. In general, plant shoots from São Domingos had the highest elements concentrations, but only As, Mn and Zn reached phytotoxic concentrations. Concentration of Chlb in shoots from São Domingos was higher than those from Corte do Pinto. No significant differences were obtained between concentrations of Chla, total protein, proline and acid-soluble thiols in shoots collected in both areas, as well as SOD activity (total and specific) and specific CAT activity. Total CAT activity varied with population being lower in the shoots of the plants from São Domingos, but no correlation was obtained between this enzymatic activity and the concentrations of the studied elements in shoots.Lavandula pedunculata plants are able to survive in soils developed on different mine wastes with multielemental contamination and low fertility showing no symptoms (visible and physiological) of phytotoxicity or deficiency.
Afficher plus [+] Moins [-]Characterizing the spatial distribution of ambient ultrafine particles in Toronto, Canada: A land use regression model Texte intégral
2016
Weichenthal, Scott | Van Ryswyk, Keith | Goldstein, Alon | Shekarrizfard, Maryam | Hatzopoulou, Marianne
Exposure models are needed to evaluate the chronic health effects of ambient ultrafine particles (<0.1 μm) (UFPs). We developed a land use regression model for ambient UFPs in Toronto, Canada using mobile monitoring data collected during summer/winter 2010–2011. In total, 405 road segments were included in the analysis. The final model explained 67% of the spatial variation in mean UFPs and included terms for the logarithm of distances to highways, major roads, the central business district, Pearson airport, and bus routes as well as variables for the number of on-street trees, parks, open space, and the length of bus routes within a 100 m buffer. There was no systematic difference between measured and predicted values when the model was evaluated in an external dataset, although the R² value decreased (R² = 50%). This model will be used to evaluate the chronic health effects of UFPs using population-based cohorts in the Toronto area.
Afficher plus [+] Moins [-]Degradation and sorption of the fungicide tebuconazole in soils from golf greens Texte intégral
2016
Badawi, Nora | Rosenbom, Annette E. | Jensen, Anne M.D. | Sørensen, Sebastian R.
The fungicide tebuconazole (TBZ) is used to repress fungal growth in golf greens and ensure their playability. This study determined the degradation and sorption of TBZ applied as an analytical grade compound, a commercial fungicide formulation or in combination with a surfactant product in thatch and soils below two types of greens (USGA and push-up greens) in 12-cm vertical profiles covered by three different types of turf grass. Only minor TBZ degradation was observed and it was most pronounced in treatments with the commercial fungicide product or in combination with the surfactant compared to the analytical grade compound alone. A tendency for higher TBZ sorption when applied as the formulated product and lowest sorption when applied as a formulated product in combination with the surfactant was observed, with this effect being most distinct on USGA greens. No correlation between occurrence of degradation and soil depth, green type or grass type was observed. Sorption seemed to be the main process governing the leaching risk of TBZ from the greens and a positive correlation to the organic matter content was shown. In light of these findings, organic matter content should be taken into consideration during the construction of golf courses, especially when following USGA guidelines.
Afficher plus [+] Moins [-]Sorption of non-polar organic compounds by micro-sized plastic particles in aqueous solution Texte intégral
2016
Hüffer, Thorsten | Hofmann, Thilo
The presence of microscale polymer particles (i.e., microplastics) in the environment has become a major concern in recent years. Sorption of organic compounds by microplastics may affect the phase distribution within both sediments and aqueous phases. To investigate this process, isotherms were determined for the sorption of seven aliphatic and aromatic organic probe sorbates by four polymers with different physico-chemical properties. Sorption increased in the order polyamide < polyethylene < polyvinylchloride < polystyrene. This order does not reflect the particle sizes of the investigated microplastics within the aqueous dispersions, indicating the influence of additional factors (e.g., π-π-interactions) on the sorption of aromatic compounds by polystyrene. Linear isotherms by polyethylene suggested that sorbate uptake was due to absorption into the bulk polymer. In contrast, non-linear isotherms for sorption by PS, PA, and PVC suggest a predominance of adsorption onto the polymer surface, which is supported by the best fit of these isotherms using the Polanyi-Manes model. A strong relationship between the sorption coefficients of the microplastics and the hydrophobicity of the sorbates suggests that hydrophobic interactions are of major importance.
Afficher plus [+] Moins [-]Hotspots of black carbon and PM2.5 in an urban area and relationships to traffic characteristics Texte intégral
2016
Targino, Admir Créso | Gibson, Mark David | Krecl, Patricia | Rodrigues, Marcos Vinicius Costa | dos Santos, Maurício Moreira | de Paula Corrêa, Marcelo
Three instrumented bicycles were used to measure black carbon (BC) and PM2.5 concentrations in a midsized city in southern Brazil. The objective of this study was to map the spatial distribution of BC and PM2.5, to identify air pollution hotspots and to assess factors that may affect the concentrations of these pollutants, e.g. traffic volume, number of heavy-duty diesel vehicles (HDDV), position of traffic signals and street incline. The cyclists collected data in the city centre along streets of different traffic density during nine sampling sessions in the weekday morning and afternoon rush hours, between March 13 and April 28, 2015. The sampling by bicycle covered an area of 2.70 km2, over variable elevation, and travelled a total distance of 215 km. BC and PM2.5 exhibited a large spatial variability on a scale of tens of metres and the concentrations were positively correlated with traffic counts, but exhibited a stronger relationship with the number of HDDV. These results imply that older buses and diesel-powered trucks may be the main driver behind the high pollution levels in the city's inner core. We observed a strong relationship between BC concentrations at junctions managed by traffic signals and the quantity of HDDV. The mean BC concentration was found to be 8.10 μg m−3 near traffic signals located on an inclined street (HDDV > 100 vehicles h−1) compared to traffic signals on flat terrain (6.00 μg m−3), which can be attributed to the higher acceleration required at the start of motion. This pattern was less evident for PM2.5 concentrations.
Afficher plus [+] Moins [-]Microplastics and mesoplastics in fish from coastal and fresh waters of China Texte intégral
2016
Jabeen, Khalida | Su, Lei | Li, Jiana | Yang, Dongqi | Tong, Chunfu | Mu, Jingli | Shi, Huahong
Plastic pollution is a growing global concern. In the present study, we investigated plastic pollution in 21 species of sea fish and 6 species of freshwater fish from China. All of the species were found to ingest micro- or mesoplastics. The average abundance of microplastics varied from 1.1 to 7.2 items by individual and 0.2–17.2 items by gram. The average abundance of mesoplastics varied from 0.2 to 3.0 items by individual and 0.1–3.9 items by gram. Microplastics were abundant in 26 species, accounting for 55.9–92.3% of the total number of plastics items in each species. Thamnaconus septentrionalis contained the highest abundance of microplastics (7.2 items/individual). The average abundance of plastics in sea benthopelagic fishes was significantly higher than in freshwater benthopelagic fishes by items/individual. The plastics were dominanted by fiber in shape, transparent in color and cellophane in composition. The proportion of plastics in the stomach to the intestines showed great variation in different species, ranging from 0.5 to 1.9 by items/individual. The stomach of Harpodon nehereus and intestines of Pampus cinereus contained the highest number of plastics, (3.3) and (2.7), respectively, by items/individual. Our results suggested that plastic pollution was widespread in the investigated fish species and showed higher abundance in comparison with worldwide studies. The ingestion of plastics in fish was closely related to the habitat and gastrointestinal tract structure. We highly recommend that the entire gastrointestinal tract and digestion process be used in future investigations of plastic pollution in fish.
Afficher plus [+] Moins [-]Wintertime haze deterioration in Beijing by industrial pollution deduced from trace metal fingerprints and enhanced health risk by heavy metals Texte intégral
2016
Lin, Yu-Chi | Xu, Shijie | Chou, Charles C.-K. | Zhang, Renjian | Wu, Yunfei | Kao, Shuh-Ji | Luo, Li | Huang, Chao-Hao | Lin, Shuen-Hsin | Huang, Yi-Tang
Airborne particulate matter (PM) was collected in Beijing between 24 February and 12 March 2014 to investigate chemical characteristics and potential industrial sources of aerosols along with health risk of haze events. Results showed secondary inorganic aerosol was the major contributor to PM2.5 during haze days. Utilizing specific elements, including Fe, La, Tl and As, as fingerprinting tracers, four emission sources, namely iron and steel manufacturing, petroleum refining, cement plant, and coal combustion were explicitly identified; their elevated contributions to PM during haze days were also estimated. The average cancer risk from exposure to inhalable PM toxic metals was 1.53 × 10⁻⁴ on haze days, which is one order of magnitude higher than in other developed cities. These findings suggested heavy industries emit large amounts of not only primary PM but also precursor gas pollutants, leading to secondary aerosol formation and harm to human health during haze days.
Afficher plus [+] Moins [-]Occurrence and distribution of antibiotics, antibiotic resistance genes in the urban rivers in Beijing, China Texte intégral
2016
Xu, Yan | Guo, Changsheng | Luo, Yi | Lv, Jiapei | Zhang, Yuan | Lin, Haixia | Wang, Li | Xu, Jian
The occurrence and distribution of sulfonamide and tetracycline, corresponding bacterial resistant rate and resistance genes (ARGs) and two integrase genes were investigated in seven urban rivers in Beijing, China. The total concentration of sulfonamide and tetracycline ranged from 1.3 × 101–1.5 × 103 ng/L and 3.9 × 101–5.4 × 104 ng/L for water, and 1.0 × 100–2.7 × 102 and 3.1 × 101–1.6 × 102 ng/g for sediment, respectively. The sul resistant rate was 2–3 times higher than tet resistant rate in both surface water and sediment. The average rate of sul resistance and tet resistance were up to 81.3% and 38.6% in surface water, 89.1% and 69.4% in the sediment, respectively. The sul1, tetA and tetE genes were predominant in term of the absolute abundance. The absolute abundance of ARGs in Wenyu River and Qinghe River, which were close to the direct discharging sites, were 5–50 times higher than those in the other investigated urban rivers, suggesting that the source release played an important role in the distribution of ARGs. The sul1 and sul2 genes had positive correlation (p < 0.05) with sulfonamides, and the tet resistance genes was significantly correlated with tetracyclines (p < 0.05), indicating that some ARGs and antibiotics in the urban rivers had identical sources of pollution. Considering principal component analysis, sampling sites (QH5, QH6, B1, B2, B3 and BX2) intimated that a complex interplay of processes govern fate and transport of ARGs in the junction of rivers. These results are significant to understand the fate, and the contribution of ARGs from the source release. In view of the large-scale investigation of urban rivers system in Beijing, it reflected the bacterial resistance in sewage drainage system. Such investigation highlights the management on controlling the pollutant release which was seemed as a major driving force for the maintenance and propagation of many ARGs during the development of urbanization in the future.
Afficher plus [+] Moins [-]Distributions of organochlorine compounds in sediments from Jiulong River Estuary and adjacent Western Taiwan Strait: Implications of transport, sources and inventories Texte intégral
2016
Wu, Yuling | Wang, Xinhong | Ya, Miaolei | Li, Yongyu | Hong, Huasheng
Estuaries and coastal areas strongly influenced by terrestrial inputs resulted from anthropogenic activities. To study the distributions, origins, potential transport and burden of organochlorine compounds (OCs) from river to marginal sea, organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were investigated in surface sediments collected from a subtropical estuary (Jiulong River Estuary, JRE) and the inner shelf of adjacent Western Taiwan Strait (WTS). The concentrations of OCPs and PCBs were from 5.2 to 551.7 and 1.0–8.1 ng g−1 (dry weight), respectively. OCP concentrations in the JRE were higher than in adjacent WTS, and a decreasing trend with the ascending distance from the estuary to the open sea was observed. Concentrations of DDTs were quite high in the upper reach of the estuary, inferred from antifouling paint on fishing boats of a local shipping company. According to established sediment quality guidelines, DDTs in the JRE posed potential ecological risk. HCHs in the estuary were mainly derived from the weathered HCHs preserved in the agriculture soils via local major river runoffs.OCPs patterns showed that OCPs in the south coast of WTS were resulted from local sources via river input, while OCPs in the north coast attributed to the long-range transport derived by the Fujian-Zhejiang Coastal Current.Minor variations of PCB concentrations and homologs indicated that PCBs were not the main pollutant in the agricultural region, consistent lighter PCBs reflected industrial PCBs were transported via atmospheric deposition derived by East Asia Monsoon. Moreover, the primary distribution pattern founded for DDTs and the considerable mass inventories and burdens calculated (258.1 ng cm−2 and 10.4 tones for OCPs) that higher than Pearl River Delta and Yangtze River Delta, together suggested that the contaminated sediments in the study area may be a potential source of OCPs to the global ocean.
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