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Airborne psychotropic substances in eight Italian big cities: Burdens and behaviours 全文
2012
Cecinato, Angelo | Balducci, Catia | Romagnoli, Paola | Perilli, Mattia
Psychotropic substances were monitored in eight big cities of Italy over one year, starting in May 2010, in the frame of the Ariadrugs Project. Yearly average concentrations ranged from 0.02 ± 0.01 to 0.26 ± 0.11 ng/m³ for cocaine, from 0.05 ± 0.05 to 0.96 ± 1.37 ng/m³ for cannabinoids, from 16 ± 6 to 61 ± 28 ng/m³ for nicotine, and from 1.0 ± 0.8 to 8 ± 7 ng/m³ for caffeine. Palermo and Turin were the cities suffering the lowest and the highest psychotropic substance concentrations, respectively. Nicotine and cocaine exhibited trends less seasonally modulated than common air toxicants. Caffeine and cannabinoids peaked in winter dropping close to zero from May to August. In Rome, where various anthropic contours were investigated in February 2011, differences were observed both in net concentrations and ratios of psychotropic substances vs. regulated toxicants. Ambient drugs look as a consequence of addiction and their burdens give insights about the corresponding consumes.
显示更多 [+] 显示较少 [-]Bioaccumulation of microcystins in two freshwater gastropods from a cyanobacteria-bloom plateau lake, Lake Dianchi 全文
2012
Zhang, Junqian | Wang, Zhi | Song, Zhuoyan | Xie, Zhicai | Li, Lin | Song, Lirong
To investigate the bioaccumulation patterns of microcystins (MCs) in organs of two gastropods, samples were collected in Lake Dianchi monthly from May to October, 2008, when cyanobacteria typically bloom. The average MCs concentrations for Radix swinhoei (pulmonate) and Margarya melanioides (prosobranch) tended to be similar for the different organs: the highest values in the hepatopancreas (9.33 by 3.74μg/g DW), followed by digestive tracts (1.66 by 3.03μg/g DW), gonads (0.45 by 1.34μg/g DW) and muscles (0.22 by 0.40μg/g DW). Pulmonate had higher value than prosobranch because of the stronger bioaccumulation ability in hepatopancreas. The levels in organs of R. swinhoei were correlated with environmentally dissolved MCs, but influenced by intracellular MCs for M. melanioides. The estimated MCs concentrations in edible parts of M. melanioides were beyond the WHO’s provisional tolerable daily intake (0.04μg/kg), suggesting the risk of consumption of M. melanioides from the lake.
显示更多 [+] 显示较少 [-]Spatial patterns and temporal trends in mercury concentrations, precipitation depths, and mercury wet deposition in the North American Great Lakes region, 2002–2008 全文
2012
Risch, Martin R. | Gay, David A. | Fowler, Kathleen K. | Keeler, Gerard J. | Backus, Sean M. | Blanchard, Pierrette | Barres, James A. | Dvonch, J Timothy
Annual and weekly mercury (Hg) concentrations, precipitation depths, and Hg wet deposition in the Great Lakes region were analyzed by using data from 5 monitoring networks in the USA and Canada for a 2002–2008 study period. High-resolution maps of calculated annual data, 7-year mean data, and net interannual change for the study period were prepared to assess spatial patterns. Areas with 7-year mean annual Hg concentrations higher than the 12 ng per liter water-quality criterion were mapped in 4 states. Temporal trends in measured weekly data were determined statistically. Monitoring sites with significant 7-year trends in weekly Hg wet deposition were spatially separated and were not sites with trends in weekly Hg concentration. During 2002–2008, Hg wet deposition was found to be unchanged in the Great Lakes region and its subregions. Any small decreases in Hg concentration apparently were offset by increases in precipitation.
显示更多 [+] 显示较少 [-]Methylmercury and dissolved organic carbon relationships in a wetland-rich watershed impacted by elevated sulfate from mining 全文
2012
Berndt, Michael E. | Bavin, Travis K.
Methylmercury (MeHg), dissolved organic carbon (DOC), and sulfate (SO₄ ⁼) relationships were investigated in the mining-influenced St. Louis River watershed in northeast Minnesota. Fewer wetlands and higher SO₄ ⁼ in the mining region lead to generally lower availability and solubility of DOC in mining streams compared to non-mining streams. MeHg concentrations, however, are similarly low in mining and non-mining streams during low flow periods, implying that the extra DOC found in non-mining streams carries little MeHg with it during these periods. High water levels elevated MeHg concentrations in both stream types owing to release from wetlands of DOC species that contain MeHg and remain relatively soluble in streams with elevated ionic strength. In-river methylation appeared to be a negligible component of the MeHg budget for the St. Louis River during this study as MeHg and DOC concentrations were intermediate to those observed in its mining-influenced and wetland-dominated tributaries.
显示更多 [+] 显示较少 [-]Methylmercury bioaccumulation in invertebrates of boreal streams in Norway: Effects of aqueous methylmercury and diet retention 全文
2012
de Wit, Heleen A. | Kainz, Martin J. | Lindholm, Markus
Transfer of aqueous methylmercury (MeHg) to primary consumers in aquatic foodwebs is poorly understood despite its importance for bioaccumulation of MeHg. We studied bioaccumulation of MeHg in simple aquatic food chains of two humic boreal streams in relation to streamwater chemistry, food web characteristics and dietary fatty acid (FA) biomarkers. Transfer of aqueous MeHg into primary consumers was similar in both streams, resulting in higher MeHg in consumers in the MeHg-rich stream. Trophic enrichment of MeHg and dietary retention of FA biomarkers was the same in both streams, suggesting that exposure to aqueous MeHg at the base of the food chain determined levels of MeHg in biota. In addition, contents of dietary biomarkers suggested that ingestion of algae reduced MeHg bioaccumulation, while ingestion of bacteria stimulated MeHg uptake. Dietary uptake of bacteria could thus be an important pathway for MeHg-transfer at the bottom of food chains in humic streams.
显示更多 [+] 显示较少 [-]Polycyclic aromatic hydrocarbons (PAHs) in the Mediterranean Sea: Atmospheric occurrence, deposition and decoupling with settling fluxes in the water column 全文
2012
Castro-Jiménez, Javier | Berrojalbiz, Naiara | Wollgast, Jan | Dachs, Jordi
∑₃₀PAH gas phase concentrations (13–86 and 22–40 ng m⁻³ in the Mediterranean and Black Seas, respectively) dominated the atmospheric levels due to the high contribution of phenanthrene, dibenzothiophene and their alkylated derivates. The high variability of PAH atmospheric concentrations in the different sub-basins is due to several factors (i.e. air-mass trajectory, proximity to sources and losses by deposition). The ∑₃₀PAH atmospheric deposition (dominated by low MW PAH net air–water diffusive fluxes) is estimated to be ∼3100 ton y⁻¹ (Mediterranean) and ∼500 ton y⁻¹ (Black Sea). Net volatilization for certain PAHs was estimated. Deposition fluxes (1–2 orders of magnitude higher than reported PAH settling fluxes in the water column) confirm an important depletion/sink of water column PAH in the photic zone, especially for low MW PAHs. Degradation processes in the water column may be responsible for this decoupling. Conversely, high MW PAHs dry deposition fluxes are similar to their settling fluxes.
显示更多 [+] 显示较少 [-]First evidence on different transportation modes of arsenic and phosphorus in arsenic hyperaccumulator Pteris vittata 全文
2012
Lei, Mei | Wan, Xiao-ming | Huang, Ze-chun | Chen, Tong-bin | Li, Xue-wen | Liu, Ying-ru
Arsenic (As) reduction and translocation are key processes for As hyperaccumulation by the hyperaccumulator Pteris vittata L. Micro-X-ray adsorption spectroscopy of P. vittata’s rhizoid tissues revealed that As reduction mainly occurred in endodermis during translocation from epidermis to vascular bundle. Prior to reduction, arsenate (As (V)) translocation was an active process requiring energy and employing a phosphate (P) transporter. Use of a synchrotron X-ray microprobe showed that As (V) and P were cotransported and that this process could be enhanced by As (V) exposure or P deficiency but restrained by energy release inhibition caused by 2,4-dinitrophenol or sodium orthovanadate. In contrast, after As reduction, As(III) translocation differed from P translocation and was more efficient, appearing free from the apparent endodermal blockage. The results here revealed the role of the P transporter on As translocation as well as the key role of As reduction in As hyperaccumulation by P. vittata.
显示更多 [+] 显示较少 [-]Temporal and spatial trends of perfluoroalkyl substances in liver of roe deer (Capreolus capreolus) 全文
2012
Falk, Sandy | Brunn, Hubertus | Schröter-Kermani, Christa | Failing, Klaus | Georgii, Sebastian | Tarricone, Kathrin | Stahl, Thorsten
For more than 50 years perfluoroalkyl substances (PFASs) have found worldwide industrial and household uses. Some PFASs are presumed to be persistent and bioaccumulative. Roe deer (Capreolus capreolus) are thought to be a suitable bioindicator for the accumulation of organic xenobiotics. Due to the ubiquitous nature of PFASs in the environment a retrospective study on temporal trends was carried out. A total of 110 deer liver pools collected from 1989 to 2010 in Germany were analyzed for their levels of PFASs. The highest concentrations were measured for perfluorooctane sulfonate (PFOS) (median 6.3 μg/kg). Perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA) were detected with median concentrations of 0.5 μg/kg, 1.2 μg/kg and 0.3 μg/kg, respectively, while concentrations of the other PFASs were below the limit of quantification. PFOS concentrations decreased significantly (rₛ = −0.741; p = <0.0001) from 9.2 μg/kg in 2000 to 1.8 μg/kg in 2010.
显示更多 [+] 显示较少 [-]Influence of sugarcane burning on indoor/outdoor PAH air pollution in Brazil 全文
2012
Cristale, Joyce | Silva, Flávio Soares | Zocolo, Guilherme Julião | Marchi, Mary Rosa Rodrigues
This work presents the influence of sugarcane burning on PAH levels and their profiles at a residence located in Araraquara (SP, Brazil), a city surrounded by sugarcane plantations. The average concentrations of total PAHs (ΣPAHs) associated with atmospheric particulate matter were higher during the burning period (ΣPAHs 22.9 ng m⁻³) than in the non-burning period (ΣPAH 2.35 ng m⁻³). A comparison of our results with previous studies regarding PAH levels and their profiles in Araraquara outdoor air indicated that sugarcane burning was the main PAH air source in the indoor harvesting season samples. The benzo[a]pyrene equivalent (BaPₑq) was used for cancer risk assessment, and higher average values were obtained in the harvesting season air samples (1.7 ng m⁻³) than in the non-harvesting air samples (0.07 ng m⁻³). These findings suggest that sugarcane burning during the harvesting season can represent a public health risk in affected cities.
显示更多 [+] 显示较少 [-]How healthy is urban horticulture in high traffic areas? Trace metal concentrations in vegetable crops from plantings within inner city neighbourhoods in Berlin, Germany 全文
2012
Säumel, Ina | Kotsyuk, Iryna | Hölscher, Marie | Lenkereit, Claudia | Weber, Frauke | Kowarik, Ingo
Food production by urban dwellers is of growing importance in developing and developed countries. Urban horticulture is associated with health risks as crops in urban settings are generally exposed to higher levels of pollutants than those in rural areas. We determined the concentration of trace metals in the biomass of different horticultural crops grown in the inner city of Berlin, Germany, and analysed how the local setting shaped the concentration patterns. We revealed significant differences in trace metal concentrations depending on local traffic, crop species, planting style and building structures, but not on vegetable type. Higher overall traffic burden increased trace metal content in the biomass. The presence of buildings and large masses of vegetation as barriers between crops and roads reduced trace metal content in the biomass. Based on this we discuss consequences for urban horticulture, risk assessment, and planting and monitoring guidelines for cultivation and consumption of crops.
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