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Formaldehyde exposure in gross anatomy laboratory of Suranaree University of Technology: a comparison of area and personal sampling Full text
2015
Saowakon, Naruwan | Ngernsoungnern, Piyada | Watcharavitoon, Pornpun | Ngernsoungnern, Apichart | Kosanlavit, Rachain
Cadavers are usually preserved by embalming solution which is composed of formaldehyde (FA), phenol, and glycerol. Therefore, medical students and instructors have a higher risk of exposure to FA inhalation from cadavers during dissection. Therefore, the objective of this study was to evaluate the FA exposure in indoor air and breathing zone of medical students and instructors during dissection classes in order to investigate the relationship between them. The indoor air and personal air samples in breathing zone were collected three times during anatomy dissection classes (in January, August, and October of 2014) with sorbent tubes, which were analyzed by high-performance liquid chromatography (HPLC). The air cleaner machines were determined by weight measurement. Pulmonary function tests and irritation effects were also investigated. The mean of FA concentrations ranged from 0.117 to 0.415 ppm in the indoor air and from 0.126 to 1.176 ppm in the breathing zone of students and instructors. All the personal exposure data obtained exceeded the threshold limit of NIOSH and WHO agencies. The air cleaner machines were not significant difference. The pulmonary function of instructors showed a decrease during attention of classes and statistically significant decreasing in the instructors more than those of the students. Clinical symptoms that were observed in nose and eyes were irritations with general fatigue. We suggested that the modified exhaust ventilation and a locally ventilated dissection work table were considered for reducing FA levels in the gross anatomy dissection room.
Show more [+] Less [-]Recent trends in chloride and sodium concentrations in the deep subalpine lakes (Northern Italy) Full text
2015
Rogora, Michela | Mosello, Rosario | Kamburska, Lyudmila | Salmaso, Nico | Cerasino, Leonardo | Leoni, Barbara | Garibaldi, Letizia | Soler, Valentina | Lepori, Fabio | Colombo, Luca | Buzzi, Fabio
A growing concern exists about the effects of chloride (Cl) on freshwater systems. Increasing Cl concentrations have been observed in the last few decades in several rivers and lakes, mainly in northern countries. In Italy, present levels and temporal changes of sodium (Na) and Cl in water bodies have rarely been assessed. Based on long-term data for the lakes of the subalpine district in Italy (Maggiore, Lugano, Como, Iseo, Garda), we analyzed trends affecting Cl and Na concentrations during the last 25 years, with the aim of identifying temporal changes and assessing possible causes. An in-depth analysis is presented for Lake Maggiore. Positive temporal Na and Cl trends were evident in all studied lakes, with the trends increasing since early 2000s. Data for Lake Maggiore tributaries showed a clear seasonality (higher values in winter and early spring). The NaCl used as road de-icing agent, together with Cl discharge from wastewater treatment plants, were identified as the main causes for the observed trends. Chloride concentrations in the lakes are below the threshold limit for reduced water quality and below concentrations known to harm aquatic biota. However, considering the relevance of deep subalpine lakes, representing almost 80 % of the total freshwater volume in Italy, these trends indicate an important chemical change, which warrants further analysis.
Show more [+] Less [-]Spatial and seasonal variations of methylmercury in European glass eels (Anguilla anguilla) in the Adour estuary (France) and relation to their migratory behaviour Full text
2015
Claveau, Julie | Monperrus, Mathilde | Jarry, Marc | Pinaly, Herve | Baudrimont, Magalie | Gonzalez, Patrice | Amouroux, David | Bardonnet, Agnès | Bolliet, Valérie
Spatial and seasonal variations of methylmercury in European glass eels (Anguilla anguilla) in the Adour estuary (France) and relation to their migratory behaviour Full text
2015
Claveau, Julie | Monperrus, Mathilde | Jarry, Marc | Pinaly, Herve | Baudrimont, Magalie | Gonzalez, Patrice | Amouroux, David | Bardonnet, Agnès | Bolliet, Valérie
Overall recruitment of European glass eels (Anguilla anguilla) has decreased significantly since the early 1980s. Due to their long life cycle, benthic/demersal habits and high lipid content, eels might accumulate high concentrations of contaminants, but data concerning glass eels are still scarce. This study provides original data on methylmercury (MeHg) concentrations in glass eels at spatial (marine and estuarine), annual and seasonal scales. The relationship between MeHg concentrations in glass eels and their propensity to migrate up estuaries was also investigated. MeHg data were individually related to the eels’ energetic condition which was estimated by dry weight. Glass eel migratory behaviour was investigated in an experimental flume and related to the MeHg concentration and dry weight at the individual scale. Marine and estuarine glass eels were caught from 2004 to 2011. There was a strong inverse correlation between MeHg concentrations and dry weight. MeHg concentrations increased in marine and estuarine glass eels from 2004 to 2009 and from 2004 to 2010, respectively, and then, both groups decreased in 2011. On a seasonal time scale, MeHg concentrations were higher at the end of the fishing season (April). MeHg bioaccumulation is likely to result from different sources, but the lack of significant differences between marine and estuarine glass eels suggests that direct contamination during estuarine migration is low. Other sources such as maternal transfer or oceanic contamination are discussed.
Show more [+] Less [-]Spatial and seasonal variations of methylmercury in European glass eels (Anguilla anguilla) in the Adour estuary (France) and relation to their migratory behaviour Full text
2015
Claveau, Julie | Monperrus, Mathilde | Amouroux, David | Jarry, Marc | Pinaly, Hervé | Baudrimont, Magalie | Gonzalez, Patrice | Bardonnet, Agnes | Bolliet, Valérie | Ecologie Comportementale et Biologie des Populations de Poissons (ECOBIOP) ; Institut National de la Recherche Agronomique (INRA)-Université de Pau et des Pays de l'Adour (UPPA) | Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM) ; Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | J.C. ’ s PhD thesis was funded by the University of Pau et les Pays de l ’ Adour (ED 211). The project was partly supported by funding from the Office National de l ’ Eau and Milieux Aquatiques (ONEMA), from the European Union within the framework of the ORQUE SUDOE project, the Conseil Général des Pyrénées Atlantiques within the framework of the EXPLOR project and by the University of Pau (BQR MIRA)
International audience | Overall recruitment of European glass eels (Anguilla anguilla) has decreased significantly since the early 1980s. Due to their long life cycle, benthic/demersal habits and high lipid content, eels might accumulate high concentrations of contaminants, but data concerning glass eels are still scarce. This study provides original data on methylmercury (MeHg) concentrations in glass eels at spatial (marine and estuarine), annual and seasonal scales. The relationship between MeHg concentrations in glass eels and their propensity to migrate up estuaries was also investigated. MeHg data were individually related to the eels’ energetic condition which was estimated by dry weight. Glass eel migratory behaviour was investigated in an experimental flume and related to the MeHg concentration and dry weight at the individual scale. Marine and estuarine glass eels were caught from 2004 to 2011. There was a strong inverse correlation between MeHg concentrations and dry weight. MeHg concentrations increased in marine and estuarine glass eels from 2004 to 2009 and from 2004 to 2010, respectively, and then, both groups decreased in 2011. On a seasonal time scale, MeHg concentrations were higher at the end of the fishing season (April). MeHg bioaccumulation is likely to result from different sources, but the lack of significant differences between marine and estuarine glass eels suggests that direct contamination during estuarine migration is low. Other sources such as maternal transfer or oceanic contamination are discussed
Show more [+] Less [-]Long-term exposure of rapeseed (Brassica napus L.) to ZnO nanoparticles: anatomical and ultrastructural responses Full text
2015
Mousavi Kouhi, Seyed Mousa | Lahouti, Mehrdad | Ganjeali, Ali | Entezari, Mohammad H.
Rapid development of nanotechnology in recent years has raised concerns about nanoparticle (NPs) release into the environment and its adverse effects on living organisms. The present study is the first comprehensive report on the anatomical and ultrastructural changes of a variety of cells after long-term exposure of plant to NPs or bulk material particles (BPs). Light and electron microscopy revealed some anatomical and ultrastructural modifications of the different types of cell in the root and leaf, induced by both types of treatment. Zinc oxide (ZnO) BPs-induced modifications were surprisingly more than those induced by ZnO NPs. The modifications induced by ZnO BPs or ZnO NPs were almost similar to those induced by excess Zn. Zn content of the root and leaf of both ZnO NPs- and ZnO BPs-treated plants was severely increased, where the increase was greater in the plants treated with ZnO BPs. Overall, these results indicate that the modifications induced by ZnO particles can be attributed, at least partly, to the Zn²⁺ dissolution by ZnO particles rather than their absorption by root and their subsequent effects.
Show more [+] Less [-]Fish consumption recommendations to conform to current advice in regard to mercury intake Full text
2015
Vieira, H. C. | Morgado, F. | Soares, A. M. V. M. | Abreu, S. N.
Fish consumption recommendations to conform to current advice in regard to mercury intake Full text
2015
Vieira, H. C. | Morgado, F. | Soares, A. M. V. M. | Abreu, S. N.
This article reviews fish consumption data, mercury tolerable intake values, and mercury (Hg) content in fish, based on several reports from the Food and Agriculture Organization and European Union. The study assumptions are valid based on the current established USEPA reference dose (RfD). Combining the number of meals (per week), amount of fish ingested (by meal), and levels of MeHg in fish, this study calculates and presents isocurves indicating the maximum number of fishmeal per week without exceeding the USEPA RfD for methylmercury (MeHg). RfD are assumed to be the “exposure dose that is likely to be without deleterious effect even if continued exposure occurs over a lifetime.” The study points out that even considering a single 50-g fish meal per week, the USEPA RfD would be exceeded, triggered by values above 0.84 μg g⁻¹ of MeHg in fish, and this despite being allowed levels up to 1.0 μg g⁻¹ of MeHg in fish consumption!—Have we a health risk? Fish consumption is expected to be relatively stable, while anthropogenic mercury emissions are expected to stabilize or even to increase beyond current values. How many meals of fish per week can we have, combining the number of fish meals per week, amount of fish ingested by meal, and levels of MeHg in fish?
Show more [+] Less [-]Fish consumption recommendations to conform to current advice in regard to mercury intake Full text
2015 | 1000
Vieira, H. C. | Morgado, F. | Soares, A. M. V. M. | Abreu, S. N.
This article reviews fish consumption data, mercury tolerable intake values, and mercury (Hg) content in fish, based on several reports from the Food and Agriculture Organization and European Union. The study assumptions are valid based on the current established USEPA reference dose (RfD). Combining the number of meals (per week), amount of fish ingested (by meal), and levels of MeHg in fish, this study calculates and presents isocurves indicating the maximum number of fishmeal per week without exceeding the USEPA RfD for methylmercury (MeHg). RfD are assumed to be the Bexposure dose that is likely to be without deleterious effect even if continued exposure occurs over a lifetime.^ The study points out that even considering a single 50-g fish meal per week, the USEPA RfD would be exceeded, triggered by values above 0.84 μg g−1 of MeHg in fish, and this despite being allowed levels up to 1.0 μg g−1 of MeHg in fish consumption!—Have we a health risk? Fish consumption is expected to be relatively stable, while anthropogenic mercury emissions are expected to stabilize or even to increase beyond current values. How many meals of fish per week can we have, combining the number of fish meals per week, amount of fish ingested by meal, and levels of MeHg in fish?
Show more [+] Less [-]Pollutant toxicity and detoxification by humic substances: mechanisms and quantitative assessment via luminescent biomonitoring Full text
2015
Kudryasheva, N. S. | Tarasova, A. S.
The paper considers mechanisms of detoxification of pollutant solutions by water-soluble humic substances (HSs), natural detoxifying agents. The problems and perspectives of bioassay application for toxicity monitoring of complex solutions are discussed from ecological point of view. Bioluminescence assays based on marine bacteria and their enzymes are of special attention here; they were shown to be convenient tools to study the detoxifying effects on cellular and biochemical levels. The advantages of bioluminescent enzymatic assay for monitoring both integral and oxidative toxicities in complex solutions of model pollutants and HS were demonstrated. The efficiencies of detoxification of the solutions of organic oxidizers and salts of metals (including radioactive ones) by HS were analyzed. The dependencies of detoxification efficiency on time of exposure to HS and HS concentrations were demonstrated. Antioxidant properties of HS were considered in detail. The detoxifying effects of HS were shown to be complex and regarded as ‘external’ (binding and redox processes in solutions outside the organisms) and/or ‘internal’ organismal processes. The paper demonstrates that the HS can stimulate a protective response of bacterial cells as a result of (1) changes of rates of biochemical reactions and (2) stabilization of mucous layers outside the cell walls. Acceleration of auto-oxidation of NADH, endogenous reducer, by HS was suggested as a reason for toxicity increase in the presence of HS due to abatement of reduction ability of intracellular media.
Show more [+] Less [-]Evaluation of ettringite-related swelling mechanisms for treated chromite ore processing residue Full text
2015
Moon, Deok Hyun | Wazne, Mahmoud | Dermatas, Dimitris | Sanchez, Adriana M. | Cheong, Kyung Hoon | Park, Jeong-Hun
Accelerated one-dimensional unconfined swell tests were conducted for ferrous sulfate chromite ore processing residue (COPR) field-treated samples. The field-treated samples were subjected to wet and dry cycles over 100 days to accelerate the lithification of the samples. Parallel laboratory experiments were performed to investigate the effects of mineralogy on COPR swell under controlled conditions. The field and laboratory samples were treated with ferrous sulfate at a ferrous-to-Cr⁶⁺ molar stoichiometric ratios of eight (8×) and five (5×). X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) analyses were used to investigate the mineralogical changes upon treatment. The swell results indicated that significant COPR swelling was observed in all of the tested samples. The swelling was more pronounced in the 5× treated COPR sample than in the 8× treated COPR sample. Moreover, the laboratory-treated samples showed greater swelling behavior as compared with the field-treated samples, which was most probably due to the high dry density of the COPR, indicating that dry density was a more dominant factor than lithification. XRPD and SEM-EDX results confirmed that significant ettringite formation occurred in all treated samples.
Show more [+] Less [-]Alternatives to neonicotinoid insecticides for pest control: case studies in agriculture and forestry Full text
2015
Furlan, Lorenzo | Kreutzweiser, David
Neonicotinoid insecticides are widely used for control of insect pests around the world and are especially pervasive in agricultural pest management. There is a growing body of evidence indicating that the broad-scale and prophylactic uses of neonicotinoids pose serious risks of harm to beneficial organisms and their ecological function. This provides the impetus for exploring alternatives to neonicotinoid insecticides for controlling insect pests. We draw from examples of alternative pest control options in Italian maize production and Canadian forestry to illustrate the principles of applying alternatives to neonicotinoids under an integrated pest management (IPM) strategy. An IPM approach considers all relevant and available information to make informed management decisions, providing pest control options based on actual need. We explore the benefits and challenges of several options for management of three insect pests in maize crops and an invasive insect pest in forests, including diversifying crop rotations, altering the timing of planting, tillage and irrigation, using less sensitive crops in infested areas, applying biological control agents, and turning to alternative reduced risk insecticides. Continued research into alternatives is warranted, but equally pressing is the need for information transfer and training for farmers and pest managers and the need for policies and regulations to encourage the adoption of IPM strategies and their alternative pest control options.
Show more [+] Less [-]Chronic exposures to low and high concentrations of ibuprofen elicit different gene response patterns in a euryhaline fish Full text
2015
Jeffries, Ken M. | Brander, Susanne M. | Britton, Monica T. | Fangue, Nann A. | Connon, Richard E.
Ibuprofen is one of the most commonly detected pharmaceuticals in wastewater effluent; however, the effects of ibuprofen on aquatic organisms are poorly understood. This study presents the transcriptome-wide response of the inland silverside, Menidia beryllina, to chronic exposure to ibuprofen. At the lowest exposure concentration (0.0115 mg/L), we detected a downregulation of many genes involved in skeletal development, aerobic respiration, and immune function. At the highest exposure concentration (1.15 mg/L), we detected increased expression of regulatory genes in the arachidonic acid metabolism pathway and several immune genes involved in an inflammatory response. Additionally, there was differential expression of genes involved in oxidative stress responses and a downregulation of genes involved in osmoregulation. This study provides useful information for monitoring the effects of this common wastewater effluent contaminant in the environment and for the generation of biomarkers of exposure to ibuprofen that may be transferable to other fish species.
Show more [+] Less [-]Immobilization of Cd in paddy soil using moisture management and amendment Full text
2015
LI, Jianrui | XU, Yingming
To offer scientific data support for remediation of Cd-contaminated paddy soils under reasonable water condition, pot experiment was conducted to study the effects of moisture management and amendments on Cd immobilization in a paddy soil. Application of biochar combined with organic fertilizer reduced the exchangeable Cd by 20.4, 15.7, and 13.0 % and brown rice Cd by 43.8, 35.5, and 42.1 % under continuous flooding, conventional irrigation, and wetting irrigation, respectively, compared to the controls. Under no amendments, the content of Fe(II) in root coating in the continuous flooding treatment was 2.3 and 3.6 times of that in the conventional and wetting irrigation treatments, but Cd in root coating in the continuous flooding treatment was only 82.6 and 73.8 % of that in the conventional and wetting irrigation treatments. Applying amendments increased the Fe(II) in root coating by 27.3, 59.1, and 65.0 % but reduced the Cd in root coating by 33.6, 26.5, and 25.1 % under continuous flooding, conventional irrigation, and wetting irrigation, respectively. The lower bioavailability of Cd in paddy soil and the competition for adsorption sites in root coating of rice plant between Cd²⁺and Fe²⁺reduced from bivalent ions jointly caused the lower brown rice Cd in amended soils.
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