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Sample records for organic dust toxic

  1. Toxicity of lunar dust

    NARCIS (Netherlands)

    Linnarsson, D.; Carpenter, J.; Fubini, B.; Gerde, P.; Loftus, D.; Prisk, K.; Staufer, U.; Tranfield, E.; van Westrenen, W.

    2012-01-01

    The formation, composition and physical properties of lunar dust are incompletely characterised with regard to human health. While the physical and chemical determinants of dust toxicity for materials such as asbestos, quartz, volcanic ashes and urban particulate matter have been the focus of

  2. Respiratory Toxicity of Lunar Highland Dust

    Science.gov (United States)

    James, John T.; Lam, Chiu-wing; Wallace, William T.

    2009-01-01

    Lunar dust exposures occurred during the Apollo missions while the crew was on the lunar surface and especially when microgravity conditions were attained during rendezvous in lunar orbit. Crews reported that the dust was irritating to the eyes and in some cases respiratory symptoms were elicited. NASA s vision for lunar exploration includes stays of 6 months on the lunar surface hence the health effects of periodic exposure to lunar dust need to be assessed. NASA has performed this assessment with a series of in vitro and in vivo tests on authentic lunar dust. Our approach is to "calibrate" the intrinsic toxicity of lunar dust by comparison to a nontoxic dust (TiO2) and a highly toxic dust (quartz) using intratrachael instillation of the dusts in mice. A battery of indices of toxicity is assessed at various time points after the instillations. Cultures of selected cells are exposed to test dusts to assess the adverse effects on the cells. Finally, chemical systems are used to assess the nature of the reactivity of various dusts and to determine the persistence of reactivity under various environmental conditions that are relevant to a space habitat. Similar systems are used to assess the dissolution of the dust. From these studies we will be able to set a defensible inhalation exposure standard for aged dust and predict whether we need a separate standard for reactive dust. Presently-available data suggest that aged lunar highland dust is slightly toxic, that it can adversely affect cultured cells, and that the surface reactivity induced by grinding the dust persists for a few hours after activation.

  3. Ocular toxicity of authentic lunar dust.

    Science.gov (United States)

    Meyers, Valerie E; Garcìa, Hector D; Monds, Kathryn; Cooper, Bonnie L; James, John T

    2012-07-20

    Dust exposure is a well-known occupational hazard for terrestrial workers and astronauts alike and will continue to be a concern as humankind pursues exploration and habitation of objects beyond Earth. Humankind's limited exploration experience with the Apollo Program indicates that exposure to dust will be unavoidable. Therefore, NASA must assess potential toxicity and recommend appropriate mitigation measures to ensure that explorers are adequately protected. Visual acuity is critical during exploration activities and operations aboard spacecraft. Therefore, the present research was performed to ascertain the ocular toxicity of authentic lunar dust. Small (mean particle diameter = 2.9 ± 1.0 μm), reactive lunar dust particles were produced by grinding bulk dust under ultrapure nitrogen conditions. Chemical reactivity and cytotoxicity testing were performed using the commercially available EpiOcularTM assay. Subsequent in vivo Draize testing utilized a larger size fraction of unground lunar dust that is more relevant to ocular exposures (particles lunar dust was minimally irritating. Minor irritation of the upper eyelids was noted at the 1-hour observation point, but these effects resolved within 24 hours. In addition, no corneal scratching was observed using fluorescein stain. Low-titanium mare lunar dust is minimally irritating to the eyes and is considered a nuisance dust for ocular exposure. No special precautions are recommended to protect against ocular exposures, but fully shielded goggles may be used if dust becomes a nuisance.

  4. Modeling Respiratory Toxicity of Authentic Lunar Dust

    Science.gov (United States)

    Santana, Patricia A.; James, John T.; Lam, Chiu-Wing

    2010-01-01

    The lunar expeditions of the Apollo operations from the 60 s and early 70 s have generated awareness about lunar dust exposures and their implication towards future lunar explorations. Critical analyses on the reports from the Apollo crew members suggest that lunar dust is a mild respiratory and ocular irritant. Currently, NASA s space toxicology group is functioning with the Lunar Airborne Dust Toxicity Assessment Group (LADTAG) and the National Institute for Occupational Safety and Health (NIOSH) to investigate and examine toxic effects to the respiratory system of rats in order to establish permissible exposure levels (PELs) for human exposure to lunar dust. In collaboration with the space toxicology group, LADTAG and NIOSH the goal of the present research is to analyze dose-response curves from rat exposures seven and twenty-eight days after intrapharyngeal instillations, and model the response using BenchMark Dose Software (BMDS) from the Environmental Protection Agency (EPA). Via this analysis, the relative toxicities of three types of Apollo 14 lunar dust samples and two control dust samples, titanium dioxide (TiO2) and quartz will be determined. This will be executed for several toxicity endpoints such as cell counts and biochemical markers in bronchoaveolar lavage fluid (BALF) harvested from the rats.

  5. Lunar Airborne Dust Toxicity Hazard Assessments (Invited)

    Science.gov (United States)

    Cooper, B. L.; McKay, D. S.; Taylor, L. A.; Wallace, W. T.; James, J.; Riofrio, L.; Gonzalez, C. P.

    2009-12-01

    The Lunar Airborne Dust Toxicity Assessment Group (LADTAG) is developing data to set the permissible limits for human exposure to lunar dust. This standard will guide the design of airlocks and ports for EVA, as well as the requirements for filtering and monitoring the atmosphere in habitable vehicles, rovers and other modules. LADTAG’s recommendation for permissible exposure limits will be delivered to the Constellation Program in late 2010. The current worst-case exposure limit of 0.05 mg/m3, estimated by LADTAG in 2006, reflects the concern that lunar dust may be as toxic as quartz dust. Freshly-ground quartz is known to be more toxic than un-ground quartz dust. Our research has shown that the surfaces of lunar soil grains can be more readily activated by grinding than quartz. Activation was measured by the amount of free radicals generated—activated simulants generate Reactive Oxygen Species (ROS) i.e., production of hydroxyl free radicals. Of the various influences in the lunar environment, micrometeorite bombardment probably creates the most long-lasting reactivity on the surfaces of grains, although solar wind impingement and short-wavelength UV radiation also contribute. The comminution process creates fractured surfaces with unsatisfied bonds. When these grains are inhaled and carried into the lungs, they will react with lung surfactant and cells, potentially causing tissue damage and disease. Tests on lunar simulants have shown that dissolution and leaching of metals can occur when the grains are exposed to water—the primary component of lung fluid. However, simulants may behave differently than actual lunar soils. Rodent toxicity testing will be done using the respirable fraction of actual lunar soils (particles with physical size of less than 2.5 micrometers). We are currently separating the fine material from the coarser material that comprises >95% of the mass of each soil sample. Dry sieving is not practical in this size range, so a new system

  6. Pulmonary Toxicity Studies of Lunar Dust in Rodents

    Science.gov (United States)

    Lam, Chiu-Wing; James, John T.

    2012-01-01

    NASA has been contemplating returning astronauts to the moon for long-duration habitation and research and using it as a stepping-stone to Mars. Other spacefaring nations are planning to send humans to the moon for the first time. The surface of the moon is covered by a layer of fine dust. Fine terrestrial dusts, if inhaled, are known to pose a health risk to humans. Some Apollo crews briefly exposed to moon dust that adhered to spacesuits and became airborne in the Lunar Module reported eye and throat irritation. The habitable area of any lunar landing vehicle or outpost would inevitably become contaminated with lunar dust. To assess the health risks of exposure of humans to airborne lunar dust, we evaluated the toxicity of Apollo 14 moon dust in animal lungs. Studies of the pulmonary toxicity of a dust are generally first done by intratracheal instillation (ITI) of aqueous suspensions of the test dust into the lungs of rodents. If a test dust is irritating or cytotoxic to the lungs, the alveolar macrophages, after phagocytizing the dust particles, will release cellular messengers to recruit white blood cells (WBCs) and to induce dilation of blood capillary walls to make them porous, allowing the WBCs to gain access to the alveolar space. The dilation of capillary walls also allows serum proteins and water entering the lung. Besides altering capillary integrity, a toxic dust can also directly kill the cells that come into contact with it or ingest it, after which the dead cells would release their contents, including lactate dehydrogenase (a common enzyme marker of cell death or tissue damage). In the treated animals, we lavaged the lungs 1 and 4 weeks after the dust instillation and measured the concentrations of these biomarkers of toxicity in the bronchioalveolar lavage fluids to determine the toxicity of the dust. To assess whether the inflammation and cellular injury observed in the biomarker study would lead to persistent or progressive histopathological

  7. Toxicity of lunar dust assessed in inhalation-exposed rats.

    Science.gov (United States)

    Lam, Chiu-wing; Scully, Robert R; Zhang, Ye; Renne, Roger A; Hunter, Robert L; McCluskey, Richard A; Chen, Bean T; Castranova, Vincent; Driscoll, Kevin E; Gardner, Donald E; McClellan, Roger O; Cooper, Bonnie L; McKay, David S; Marshall, Linda; James, John T

    2013-10-01

    Humans will again set foot on the moon. The moon is covered by a layer of fine dust, which can pose a respiratory hazard. We investigated the pulmonary toxicity of lunar dust in rats exposed to 0, 2.1, 6.8, 20.8 and 60.6 mg/m(3) of respirable-size lunar dust for 4 weeks (6 h/day, 5 days/week); the aerosols in the nose-only exposure chambers were generated from a jet-mill ground preparation of a lunar soil collected during the Apollo 14 mission. After 4 weeks of exposure to air or lunar dust, groups of five rats were euthanized 1 day, 1 week, 4 weeks or 13 weeks after the last exposure for assessment of pulmonary toxicity. Biomarkers of toxicity assessed in bronchoalveolar fluids showed concentration-dependent changes; biomarkers that showed treatment effects were total cell and neutrophil counts, total protein concentrations and cellular enzymes (lactate dehydrogenase, glutamyl transferase and aspartate transaminase). No statistically significant differences in these biomarkers were detected between rats exposed to air and those exposed to the two low concentrations of lunar dust. Dose-dependent histopathology, including inflammation, septal thickening, fibrosis and granulomas, in the lung was observed at the two higher exposure concentrations. No lesions were detected in rats exposed to ≤6.8 mg/m(3). This 4-week exposure study in rats showed that 6.8 mg/m(3) was the highest no-observable-adverse-effect level (NOAEL). These results will be useful for assessing the health risk to humans of exposure to lunar dust, establishing human exposure limits and guiding the design of dust mitigation systems in lunar landers or habitats.

  8. Toxic Leadership in Educational Organizations

    Science.gov (United States)

    Green, James E.

    2014-01-01

    While research on the traits and skills of effective leaders is plentiful, only recently has the phenomenon of toxic leadership begun to be investigated. This research report focuses on toxic leadership in educational organizations--its prevalence, as well as the characteristics and early indicators. Using mixed methods, the study found four…

  9. Activation of the aryl hydrocarbon receptor is the major toxic mode of action of an organic extract of a reference urban dust particulate matter mixture: The role of polycyclic aromatic hydrocarbons

    International Nuclear Information System (INIS)

    Andrysik, Zdenek; Vondracek, Jan; Marvanova, Sona; Ciganek, Miroslav; Neca, Jiri; Pencikova, Katerina; Mahadevan, Brinda; Topinka, Jan; Baird, William M.; Kozubik, Alois; Machala, Miroslav

    2011-01-01

    Highlights: → SRM1649a extract and its fractions are potent activators of AhR in a model of epithelial cells. → AhR-dependent effects include both induction of CYP1 enzymes and disruption of cell proliferation control. → Polycyclic aromatic hydrocarbons present in the neutral SRM1649a fraction are major contributors to the AhR-mediated toxic effects. → Activation of AhR and related nongenotoxic effects occur at significantly lower doses than the formation of DNA adducts and activation of DNA damage response. → More attention should be paid to the AhR-dependent nongenotoxic events elicited by urban particulate matter constituents. - Abstract: Many of the toxic and carcinogenic effects of urban air pollution have been linked to polycyclic aromatic hydrocarbons (PAHs) adsorbed to airborne particulate matter (PM). The carcinogenic properties of PAHs in complex organic mixtures derived from PM have been chiefly attributed to their mutagenicity. Nevertheless, PAHs are also potent activators of the aryl hydrocarbon receptor (AhR), which may contribute to their nongenotoxic effects, including tumor promotion. As the genotoxicity of carcinogenic PAHs in complex mixtures derived from urban PM is often inhibited by other mixture constituents, the AhR-mediated activity of urban PM extracts might significantly contribute to the carcinogenic activity of such mixtures. In the present study, we used an organic extract of the urban dust standard reference material, SRM1649a, as a model mixture to study a range of toxic effects related to DNA damage and AhR activation. Both the organic extract and its neutral aromatic fraction formed a low number of DNA adducts per nucleotide in the liver epithelial WB-F344 cells model, without inducing DNA damage response, such as tumor suppressor p53 activation and apoptosis. In contrast, we found that this extract, as well as its neutral and polar fractions, were potent inducers of a range of AhR-mediated responses, including induction

  10. Toxicity of Depleted Uranium Dust Particles: Results of a New Model

    International Nuclear Information System (INIS)

    Zucchetti, M.

    2013-01-01

    Depleted uranium (DU) is mostly composed of U-238, a naturally radioactive isotope. Concerning chemical toxicity, uranium, being a heavy metal, is known to have toxic effects on specific organs in the body, the kidneys in particular. Its effects are similar to those of other heavy metals, such as lead and cadmium. Scientific evidence resulting both from in vitro and in vivo analyses shows that current models of the mechanisms of toxicity of uranium dust are not fully satisfactory. They should be refined in order to obtain more effective responses and predictions regarding health effects. In particular, radiotoxicity potential of Depleted Uranium dust originated by military use of this material for ammunition must be re-evaluated taking into account the bystander effect, the dose enhancing effect and other minor phenomena. Uranium dust has both chemical and radiological toxicity: the synergistic aspect of the two effects has to be accounted for, in order to arrive to a complete description of the phenomenon. The combination of the two different toxicities (chemical and radiological) of depleted uranium is attempted here for the first time, approaching the long-term effects of Depleted Uranium, and in particular the carcinogenetic effects. A case study (Balkan war, 1999) is discussed. (Author)

  11. Water and organics in interplanetary dust particles

    Science.gov (United States)

    Bradley, John

    Interplanetary dust particles (IDPs) and larger micrometeorites (MMs) impinge on the upper atmosphere where they decelerate at 90 km altitude and settle to the Earths surface. Comets and asteroids are the major sources and the flux, 30,000-40,000 tons/yr, is comparable to the mass of larger meteorites impacting the Earths surface. The sedimentary record suggests that the flux was much higher on the early Earth. The chondritic porous (CP) subset of IDPs together with their larger counterparts, ultracarbonaceous micrometeorites (UCMMs), appear to be unique among known meteoritic materials in that they are composed almost exclusively of anhydrous minerals, some of them contain >> 50% organic carbon by volume as well as the highest abundances of presolar silicate grains including GEMS. D/H and 15N abundances implicate the Oort Cloud or presolar molecular cloud as likely sources of the organic carbon. Prior to atmospheric entry, IDPs and MMs spend 104-105 year lifetimes in solar orbit where their surfaces develop amorphous space weathered rims from exposure to the solar wind (SW). Similar rims are observed on lunar soil grains and on asteroid Itokawa regolith grains. Using valence electron energy-loss spectroscopy (VEELS) we have detected radiolytic water in the rims on IDPs formed by the interaction of solar wind protons with oxygen in silicate minerals. Therefore, IDPs and MMs continuously deliver both water and organics to the earth and other terrestrial planets. The interaction of protons with oxygen-rich minerals to form water is a universal process.

  12. Chapter 6: Selenium Toxicity to Aquatic Organisms

    Science.gov (United States)

    This chapter addresses the characteristics and nature of organic selenium (Se) toxicity to aquatic organisms, based on the most current state of scientific knowledge. As such, the information contained in this chapter relates to the 'toxicity assessment' phase of aquatic ecologi...

  13. Particle size: a missing factor in risk assessment of human exposure to toxic chemicals in settled indoor dust.

    Science.gov (United States)

    Cao, Zhi-Guo; Yu, Gang; Chen, Yong-Shan; Cao, Qi-Ming; Fiedler, Heidelore; Deng, Shu-Bo; Huang, Jun; Wang, Bin

    2012-11-15

    For researches on toxic chemicals in settled indoor dust, selection of dust fraction is a critical influencing factor to the accuracy of human exposure risk assessment results. However, analysis of the selection of dust fraction in recent studies revealed that there is no consensus. This study classified and presented researches on distribution of toxic chemicals according to dust particle size and on relationship between dust particle size and human exposure possibility. According to the literature, beyond the fact that there were no consistent conclusions on particle size distribution of adherent fraction, dust with particle size less than 100 μm should be paid more attention and that larger than 250 μm is neither adherent nor proper for human exposure risk assessment. Calculation results based on literature data show that with different selections of dust fractions, analytical results of toxic chemicals would vary up to 10-fold, which means that selecting dust fractions arbitrarily will lead to large errors in risk assessment of human exposure to toxic chemicals in settled dust. Taking into account the influence of dust particle size on risk assessment of human exposure to toxic chemicals, a new methodology for risk assessment of human exposure to toxic chemicals in settled indoor dust is proposed and human exposure parameter systems to settled indoor dust are advised to be established at national and regional scales all over the world. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Toxicity of Lunar Dust in Lungs Assessed by Examining Biomarkers in Exposed Mice

    Science.gov (United States)

    Lam, C.-W.; James, J. T.; Zeidler-Erdely, P. C.; Castranova, V.; Young, S. H.; Quan, C. L.; Khan-Mayberry, N.; Taylor, L. A.

    2010-01-01

    NASA is contemplating to build an outpost on the Moon for prolonged human habitation and research. The lunar surface is covered by a layer of soil, of which the finest portion is highly reactive dust. Dust samples of respirable sizes were aerodynamically isolated from two lunar soil samples of different maturities (cosmic exposure ages) collected during the Apollo 16 mission. The lunar dust samples, TiO2, or quartz, suspended in normal saline were given to groups of 5 C57 male mice by intrapharyngeal aspiration at 0. 1, 0.3, or 1.0 mg/mouse. Because lunar dust aggregates rapidly in aqueous media, some tests were conducted with dusts suspended in Survanta/saline (1:1). The mice were euthanized 7 or 30 days later, and their lungs were lavaged to assess the presence of toxicity biomarkers in bronchioalveolar lavage fluids. The overall results showed that the two lunar dust samples were similar in toxicity, they were more toxic than T102 , but less toxic than quartz. This preliminary study is a part of the large study to obtain data for setting exposure limits for astronauts living on the Moon

  15. Preliminary Assessment of Health Risks of Potentially Toxic Elements in Settled Dust over Beijing Urban Area

    Directory of Open Access Journals (Sweden)

    Dejun Wan

    2016-05-01

    Full Text Available To examine levels, health risks, sources, and spatial distributions of potentially toxic elements in settled dust over Beijing urban area, 62 samples were collected mostly from residential building outdoor surfaces, and their <63 μm fractions were measured for 12 potentially toxic elements. The results show that V, Cr, Mn, Co, Ni, and Ba in dust are from predominantly natural sources, whereas Cu, Zn, As, Cd, Sb, and Pb mostly originate from anthropogenic sources. Exposure to these elements in dust has significant non-cancer risks to children but insignificant to adults. Cancer risks of Cr, Co, Ni, As, and Cd via inhalation and dermal contact are below the threshold of 10−6–10−4 but As via dust ingestion shows a tolerable risk. The non-cancer risks to children are contributed mainly (75% by As, Pb, and Sb, and dominantly (92% via dust ingestion, with relatively higher risks mainly occurring in the eastern and northeastern Beijing urban areas. Although Cd, Zn, and Cu in dust are heavily affected by anthropogenic sources, their health risks are insignificant. Source appointments suggest that coal burning emissions, the dominant source of As, are likely the largest contributors to the health risk, and traffic-related and industrial emissions are also important because they contribute most of the Pb and Sb in dust.

  16. Acute toxicity of tobacco ( Nicotiana tobaccum ) leaf dust on ...

    African Journals Online (AJOL)

    Experiments were conducted using dry tobacco (Nicotiana tobaccum) leaves aqueous extract to determine the acute toxicity and sub lethal effects on some haematological indices of Oreochromis niloticus using static renewable bioassay method. The extract was found to be toxic with a 48-h LC50 value of 109.6 mg/l.

  17. Toxicity of common ions to marine organisms

    International Nuclear Information System (INIS)

    Pillard, D.A.; DuFresne, D.L.; Evans, J.

    1995-01-01

    Produced waters from oil and gas drilling operations are typically very saline, and these may cause acute toxicity to marine organisms due to osmotic imbalances as well as to an excess or deficiency of specific common ions. In order to better understand the relationship between toxicity and ion concentration, laboratory toxicity tests were conducted using mysid shrimp (Mysidopsis bahia), sheepshead minnow (Cyprinodon variegatus), and inland silverside (Menidia beryllina). For each species the ionic concentration of standard laboratory water was proportionally increased or decreased to produce test solutions with a range of salinities. Organisms were exposed for 48 hours. Individual ions (sodium, potassium, calcium, magnetsium, strontium, chloride, bromide, sulfate, bicarbonate, and borate) were also manipulated to examine individual ion toxicity. The three test species differ in their tolerance of salinity. Mysid shrimp show a marked decrease in survival at salinities less than approximately 5 ppt. Both fish species tolerated low salinity water, however, silversides were less tolerant of saline waters (salinity greater than 40 ppt). There were also significant differences in the responses of the organisms to different ions. The results show that the salinity of the test solution may play an important role in the responses of the organisms to the produced water effluent. Predictable toxicity/ion relationships developed in this study can be used to estimate whether toxicity in a produced water is a result of common ions, salinity, or some other unknown toxicant

  18. A comparative study of health risk of potentially toxic metals in urban and suburban road dust in the most populated city of China

    Science.gov (United States)

    Shi, Guitao; Chen, Zhenlou; Bi, Chunjuan; Wang, Li; Teng, Jiyan; Li, Yuansheng; Xu, Shiyuan

    2011-01-01

    Urban and suburban road dust samples were collected in the most populated city of China, Shanghai. Size fractions of dust particles were analyzed; metal levels of the dust were also measured. Human exposure to individual toxic metals through road dust was assessed for both children and adults. The results showed that dust particles from urban and suburban road were presented similar size distribution pattern, with most particles in the range of 100-400 μm. Urban road dust consisted of higher proportions of inhalable, thoracic and respirable particles with increased risk of adverse effects to human. In general, mean grain sizes of urban road dust were smaller than suburban dust. Total organic carbon contents and levels of Pb, Cd, Cu, Zn, Ni, Cr in urban dust were higher than those of suburban dust. But the concentrations of As and Hg from suburban dust were higher, indicting a different main source. The exposure pathway which resulted in the highest level of risk for human exposed to road dust was ingestion of this material, which was followed by dermal contact. Except for some locations, risk values of both cancer and non-cancer obtained in this study were in the receivable range on the whole. Children had greater health risks than adults. The overall risks of non-cancer in urban area were higher than those in suburban area, but the values of cancer in the two areas were comparable. As for the aggregate noncarcinogenic risk, Pb was of most concern regarding the potential occurrence of health impacts. Of the three carcinogenic metals As, Cr and Cd, the only mean risk higher than 10 -6 was Cr, accounting for a great percentage (95%) of the overall risk of cancer. Hence, potentially adverse health effects arising from Pb and Cr in road dust should arouse wide concern.

  19. Toxic effects of fluoride on organisms.

    Science.gov (United States)

    Zuo, Huan; Chen, Liang; Kong, Ming; Qiu, Lipeng; Lü, Peng; Wu, Peng; Yang, Yanhua; Chen, Keping

    2018-04-01

    Accumulation of excess fluoride in the environment poses serious health risks to plants, animals, and humans. This endangers human health, affects organism growth and development, and negatively impacts the food chain, thereby affecting ecological balance. In recent years, numerous studies focused on the molecular mechanisms associated with fluoride toxicity. These studies have demonstrated that fluoride can induce oxidative stress, regulate intracellular redox homeostasis, and lead to mitochondrial damage, endoplasmic reticulum stress and alter gene expression. This paper reviews the present research on the potential adverse effects of overdose fluoride on various organisms and aims to improve our understanding of fluoride toxicity. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Electrostatic Dust Cloth: A Passive Screening Method to Assess Occupational Exposure to Organic Dust in Bakeries

    Directory of Open Access Journals (Sweden)

    Carla Viegas

    2018-02-01

    Full Text Available Organic dust is widespread in the environment including occupational settings, such as bakeries. Recently, a new collection device—the electrostatic dust cloth (EDC—has been described for the assessment of occupational exposures. The aim of this study was to investigate the suitability of EDC for identifying the distribution patterns and exposure concentrations of particulate matter and microbial contaminants such as fungi and bacteria in bakeries. Twelve bakeries were selected, and dust was allowed to settle for 13 to 16 days on EDCs (a total of 33 samples. Particle counts and size distribution (0.3 µm, 0.5 µm, 1 µm, 2.5 µm, 5 µm and 10 µm were measured with direct-reading equipment. Higher EDC mass was significantly correlated (p values < 0.05 with higher fungal load on dichloran glycerol (DG18 and with particle size distribution in the 0.3 µm, 0.5 µm, 1.0 µm and 10.0 µm range. Fungal levels on malt extract agar (MEA ranged from 0 to 2886 CFU/m2 EDC in the warehouse setting, 0 to 500 CFU/m2 EDC in the production setting, and 0 to 3135 CFU/m2 EDC in the store. Penicillium sp. (42.56% was the most frequent fungi. Total bacterial load ranged from 0 to 18,859 CFU/m2 EDC in the warehouse, 0 to 71,656 CFU/m2 EDC in production, and 0 to 21,746 CFU/m2 EDC in the store. EDC assessment provided a longer-term integrated sample of organic dust, useful for identifying critical worksites in which particulate matter and bio-burden exposures are elevated. These findings suggest that EDC can be applied as a screening method for particulate matter-exposure assessment and as a complementary method to quantify exposures in occupational environments.

  1. Potentially toxic metal contamination of urban soils and roadside dust in Shanghai, China

    International Nuclear Information System (INIS)

    Shi Guitao; Chen Zhenlou; Xu Shiyuan; Zhang Ju; Wang Li; Bi Chunjuan; Teng Jiyan

    2008-01-01

    A detailed investigation was conducted to understand the contamination characteristics of a selected set of potentially toxic metals in Shanghai. The amount of Pb, Zn, Cu, Cr, Cd and Ni were determined from 273 soil/dust samples collected within urban area. The results indicated that concentration of all metals except Ni in soils was significant, and metal pollution was even severer in roadside dust. A series of metal spatial distribution maps were created through geostatistical analysis, and the pollution hotspots tended to associate with city core area, major road junctions, and the regions close to industrial zones. In attempt of identifying the source of metals through geostatistical and multivariate statistical analyses, it was concluded as follows: Pb, Zn and Cu mainly originated from traffic contaminants; soil Ni was associated with natural concentration; Cd largely came from point-sourced industrial pollution; and Cr, Ni in dust were mainly related to atmospheric deposition. - Human activities have led to high accumulation of potentially toxic metals in urban soils and roadside dust of Shanghai

  2. Potentially toxic metal contamination of urban soils and roadside dust in Shanghai, China

    Energy Technology Data Exchange (ETDEWEB)

    Shi Guitao [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China); Chen Zhenlou [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China)], E-mail: gt_shi@163.com; Xu Shiyuan [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China); Zhang Ju [School of Environment and Planning, Liaocheng University, Liaocheng 252059 (China); Wang Li; Bi Chunjuan [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China); Teng Jiyan [Shanghai Chongming Dongtan National Nature Reserve, Shanghai 202183 (China)

    2008-11-15

    A detailed investigation was conducted to understand the contamination characteristics of a selected set of potentially toxic metals in Shanghai. The amount of Pb, Zn, Cu, Cr, Cd and Ni were determined from 273 soil/dust samples collected within urban area. The results indicated that concentration of all metals except Ni in soils was significant, and metal pollution was even severer in roadside dust. A series of metal spatial distribution maps were created through geostatistical analysis, and the pollution hotspots tended to associate with city core area, major road junctions, and the regions close to industrial zones. In attempt of identifying the source of metals through geostatistical and multivariate statistical analyses, it was concluded as follows: Pb, Zn and Cu mainly originated from traffic contaminants; soil Ni was associated with natural concentration; Cd largely came from point-sourced industrial pollution; and Cr, Ni in dust were mainly related to atmospheric deposition. - Human activities have led to high accumulation of potentially toxic metals in urban soils and roadside dust of Shanghai.

  3. EMISSIONS OF ORGANIC AIR TOXICS FROM OPEN ...

    Science.gov (United States)

    A detailed literature search was performed to collect and collate available data reporting emissions of toxic organic substances into the air from open burning sources. Availability of data varied according to the source and the class of air toxics of interest. Volatile organic compound (VOC) and polycyclic aromatic hydrocarbon (PAH) data were available for many of the sources. Data on semivolatile organic compounds (SVOCs) that are not PAHs were available for several sources. Carbonyl and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofuran (PCDD/F) data were available for only a few sources. There were several sources for which no emissions data were available at all. Several observations were made including: 1) Biomass open burning sources typically emitted less VOCs than open burning sources with anthropogenic fuels on a mass emitted per mass burned basis, particularly those where polymers were concerned; 2) Biomass open burning sources typically emitted less SVOCs and PAHs than anthropogenic sources on a mass emitted per mass burned basis. Burning pools of crude oil and diesel fuel produced significant amounts of PAHs relative to other types of open burning. PAH emissions were highest when combustion of polymers was taking place; and 3) Based on very limited data, biomass open burning sources typically produced higher levels of carbonyls than anthropogenic sources on a mass emitted per mass burned basis, probably due to oxygenated structures r

  4. [Aluminum--occurrence and toxicity for organisms].

    Science.gov (United States)

    Ochmański, W; Barabasz, W

    2000-01-01

    Aluminium (Al.) is an ubiquitous element found in every food product. The sources of Al. are especially corn, yellow cheese, salt, herbs, spices, tea and tap water. In household Al.-made ware is a major source of the element. Al. may cause diseases in humans, especially hampers many metabolic processes especially turnover of calcium, phosphorus and iron. Salts of Al. may bind to DNA, RNA, inhibit such enzymes as hexokinase, acid and alkaline phosphatases, phosphodiesterase and phosphooxydase. Al. salts are especially harmful to nervous, hematopoietic systems and to skeleton. Al. gets to organism with food, water, cosmetics, from aluminium ware and containers. Toxicity comes from substitution of Mg and Fe ions effecting in disturbances in intracellular signaling, excretory functions and cellular growth. Neurotoxic action of Al. probably comes from substitution of Mg ions in ATP, what finally influences function of every ATP using-enzymes. There are observations in experimental models proving Al. salts are responsible for Alzheimer disease development. Toxicity of Al. to skeletal system results in diminished resistance thus tendencies to breaking, and comes from lower collagen synthesis and slowing down of mineralisation. Low erythropoietin production, inhibition of hem-synthesing enzymes and binding of Al. to transferrin, effects in anaemia. Carcinogenic effects of Al. were nor proved nor denied, but high concentrations of Al. were found in many neoplastic cells. In conclusion, we should introduce prophylactic measures effecting in less Al. intake esp. avoiding use of Al.-made ware nad controlling food for Al. content.

  5. Self-organization and oscillation of negatively charged dust particles in a 2-dimensional dusty plasma

    Energy Technology Data Exchange (ETDEWEB)

    Song, Y.L. [College of Science, China Agricultural University, Beijing 100083 (China); Huang, F., E-mail: huangfeng@cau.edu.cn [College of Science, China Agricultural University, Beijing 100083 (China); Chen, Z.Y., E-mail: chenzy@mail.buct.edu.cn [Department of Physics, Beijing University of Chemical Technology, Beijing 100029 (China); State Key Laboratory of Laser Propulsion & Application, Beijing 101416 (China); Liu, Y.H. [School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025 (China); Yu, M.Y. [Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Institute for Theoretical Physics I, Ruhr University, D-44801 Bochum (Germany)

    2016-02-22

    Negatively charged dust particles immersed in 2-dimensional dusty plasma system are investigated by molecular dynamics simulations. The effects of the confinement potential and attraction interaction potential on dust particle self-organization are studied in detail and two typical dust particle distributions are obtained when the system reaches equilibrium. The average radial velocity (ARV), average radial force (ARF) and radial mean square displacement are employed to analyze the dust particles' dynamics. Both ARVs and ARFs exhibit oscillation behaviors when the simulation system reaches equilibrium state. The relationships between the oscillation and confinement potential and attraction potential are studied in this paper. The simulation results are qualitatively similar to experimental results. - Highlights: • Self-organization and oscillation of a 2-dimensional dusty plasma is investigated. • Effect of the confinement potential on dust self-organization and oscillation is given. • Effect of the attraction potential on dust self-organization and oscillation is studied.

  6. Self-organization and oscillation of negatively charged dust particles in a 2-dimensional dusty plasma

    International Nuclear Information System (INIS)

    Song, Y.L.; Huang, F.; Chen, Z.Y.; Liu, Y.H.; Yu, M.Y.

    2016-01-01

    Negatively charged dust particles immersed in 2-dimensional dusty plasma system are investigated by molecular dynamics simulations. The effects of the confinement potential and attraction interaction potential on dust particle self-organization are studied in detail and two typical dust particle distributions are obtained when the system reaches equilibrium. The average radial velocity (ARV), average radial force (ARF) and radial mean square displacement are employed to analyze the dust particles' dynamics. Both ARVs and ARFs exhibit oscillation behaviors when the simulation system reaches equilibrium state. The relationships between the oscillation and confinement potential and attraction potential are studied in this paper. The simulation results are qualitatively similar to experimental results. - Highlights: • Self-organization and oscillation of a 2-dimensional dusty plasma is investigated. • Effect of the confinement potential on dust self-organization and oscillation is given. • Effect of the attraction potential on dust self-organization and oscillation is studied.

  7. TOXICITY BEHAVIORS IN ORGANIZATIONS: STUDY OF RELIABILITY AND VALIDITY OF TOXIC EMOTIONAL EXPERIENCES SCALE

    OpenAIRE

    Bektas, Meral; Erkal, Pinar

    2016-01-01

    In toxic organizations which are mostly destructive instead of being constrictive towards its employees, toxicity behaviors emerge as a result of the formal and informal relationships. Toxicity behaviors are often negatively affect motivation, job satisfaction or performance of the employees in workplace. Basic toxicity behaviors in organizations are: extreme jealousy, biting words, emphasis  superiority emphasis, getting angry, offending employees, strict control, heavy job workload, limited...

  8. Persistent organic contaminants in Saharan dust air masses in West Africa, Cape Verde and the eastern Caribbean

    Science.gov (United States)

    Garrison, Virginia H.; Majewski, Michael S.; Foreman, William T.; Genualdi, Susan A.; Mohammed, Azad; Massey Simonich, Stacy L.

    2014-01-01

    Anthropogenic semivolatile organic compounds (SOCs) that persist in the environment, bioaccumulate, are toxic at low concentrations, and undergo long-range atmospheric transport (LRT) were identified and quantified in the atmosphere of a Saharan dust source region (Mali) and during Saharan dust incursions at downwind sites in the eastern Caribbean (U.S. Virgin Islands, Trinidad and Tobago) and Cape Verde. More organochlorine and organophosphate pesticides (OCPPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyl (PCB) congeners were detected in the Saharan dust region than at downwind sites. Seven of the 13 OCPPs detected occurred at all sites: chlordanes, chlorpyrifos, dacthal, dieldrin, endosulfans, hexachlorobenzene (HCB), and trifluralin. Total SOCs ranged from 1.9–126 ng/m3 (mean = 25 ± 34) at source and 0.05–0.71 ng/m3 (mean = 0.24 ± 0.18) at downwind sites during dust conditions. Most SOC concentrations were 1–3 orders of magnitude higher in source than downwind sites. A Saharan source was confirmed for sampled air masses at downwind sites based on dust particle elemental composition and rare earth ratios, atmospheric back trajectory models, and field observations. SOC concentrations were considerably below existing occupational and/or regulatory limits; however, few regulatory limits exist for these persistent organic compounds. Long-term effects of chronic exposure to low concentrations of SOCs are unknown, as are possible additive or synergistic effects of mixtures of SOCs, biologically active trace metals, and mineral dust particles transported together in Saharan dust air masses.

  9. Organic Signature of Dust from the Interstellar Medium (ISM)

    Science.gov (United States)

    Freund, Friedemann; Freund, Minoru; Staple, Aaron; Scoville, John

    2001-01-01

    Dust in the ISM carries an "organic" signature in form of a distinct group of C-H stretching bands, both in emission and absorption, around 3.4 micrometers. These bands agree with the symmetrical and asymmetrical C-H stretching vibrations of aliphatic -CH2- entities and are thought to be associated with organic molecules on the surface of dust grains. We show that this interpretation is inconsistent with laboratory experiments. Synthetic MgO and natural olivine single crystals, grown from a CO/CO2/H2O-saturated melt, exhibit the same C-H stretching bands but those bands are clearly associated with C-H entities inside the dense mineral matrix. The multitude of C-H stretching bands suggests that the C-H bonds arise from polyatomic C(sub n) entities. We heated the MgO and olivine crystals to temperatures between 550-1000 K to pyrolyze the C-H bonds and to cause the C-H stretching bands to disappear. Upon annealing at moderate temperatures between 300-390 K the C-H stretching bands reappear within a few days to weeks. The C-H stretching band intensity increases linearly with the square root of time. Thus, while the pyrolysis broke the C-H bonds and caused the H to disperse in the mineral matrix, the H atoms (or H2 molecules) are sufficiently mobile to return during annealing and reestablish the C-H bonds. Dust grains that condense in a gas-laden environment (outflow of late-stage stars or in dense molecular clouds) probably incorporate the same type of Cn-H entities. Imbedded in and in part bonded to the surrounding mineral matrix, the Cn-H entities display C-H stretching bands in the 3.4 micrometer region, but their lower frequency librational modes are so strongly coupled to the lattice modes that they broaden excessively and thus become unobservable.

  10. Increased occupational coal dust toxicity in blood of central heating system workers.

    Science.gov (United States)

    Tuluce, Yasin; Ozkol, Halil; Koyuncu, Ismail; Ine, Hatice

    2011-02-01

    Coal dust causes lung diseases in occupational exposure. Reactive oxygen species have been implicated in the pathogenesis of its toxicity. In this study, serum enzymes, lipid profile and other biochemical values with oxidant/antioxidant status in whole blood and serum of central heating system workers (CHSW; the persons responsible for heating the apartment with coal) were determined to reflect the cell injury. Blood samples were obtained from CHSW (n = 25) and healthy individuals (n = 25). All values were measured in whole blood and serum. ANOVA was used for the estimation of statistical data. In the group of CHSW, creatinine, ferritin, alanin aminotransferase, aspartate aminotransferase, creatine phosphokinase, gamma glutamyl transferase, lactate dehydrogenase and glutathione reductase activities as well as triglyceride, very low density lipoprotein, protein carbonyl and malondialdehide were significantly higher, while transferrin, high density lipoprotein and catalase (CAT) activities were lower than the group of healthy individuals. This result is consistent with hypothesis that respirable coal dust generates lipid and protein oxidation and induces leakage of serum enzymes by cell damage. It also leads to imbalance in antioxidant defense system, lipid profile and other biochemical parameters.

  11. Toxic organic compounds from energy production

    Energy Technology Data Exchange (ETDEWEB)

    Hites, R.A.

    1991-09-20

    The US Department of Energy's Office of Health and Environmental Research (OHER) has supported work in our laboratory since 1977. The general theme of this program has been the identification of potentially toxic organic compounds associated with various combustion effluents, following the fates of these compounds in the environment, and improving the analytical methodology for making these measurements. The projects currently investigation include: an improved sampler for semi-volatile compounds in the atmosphere; the wet and dry deposition of dioxins and furans from the atmosphere; the photodegradation and mobile sources of dioxins and furans; and the bioaccumulation of PAH by tree bark. These projects are all responsive to OHER's interest in the pathways and mechanisms by which energy-related agents move through and are modified by the atmosphere''. The projects on gas chromatographic and liquid chromatographic tandem mass spectrometry are both responsive to OHER's interest in new and more sensitive technologies for chemical measurements''. 35 refs., 9 figs.

  12. Effect of industrial dust on some test organisms

    Energy Technology Data Exchange (ETDEWEB)

    Schuck, H.J.

    1974-01-01

    The effect of industrial dust on the growth of Lepidium sativum Cress and on spore germination and germ-tube development of Botrytis cinerea and Fusarium oxysporum was studied. Lepidium sativum was strongly inhibited and in most cases the fungi were stimulated. The effect was related to the species of trees and the district, where the dust-samples were collected.

  13. Pollution and health risk of potentially toxic metals in urban road dust in Nanjing, a mega-city of China

    International Nuclear Information System (INIS)

    Liu, Enfeng; Yan, Ting; Birch, Gavin; Zhu, Yuxin

    2014-01-01

    Spatial variations in concentrations of a suite of potentially toxic metals (Ba, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and Ca in road dusts (n = 99) from urban trunk roads (TR) in Nanjing, a mega-city in China, were established. Metal pollution levels, sources and human health risk (non-carcinogenic) were studied. In contrast to previous studies, we labeled the indicative metals relating to non-exhaust traffic emissions by comparing metal pollution between crossroad and park road dusts, and then anthropogenic sources of metals in TR dusts were assessed combining their spatial pollution patterns, principal component analysis and Pb isotopic compositions. Results showed that the metals were enriched in TR dusts compared to background soil concentrations with mean enrichment factors (EFs) of 2.2–23, indicating considerable anthropogenic influence. The degrees of metal pollution ranged from minimal to extremely high and ranked by Ca > Cu > Pb ≈ Zn > Cr ≈ Fe > Ni ≈ Ba > Mn on average. Pollution of Cr, Cu, Fe, Mn, Ni, Pb and Zn in TR dusts resulted primarily from industrial emissions (e.g., coal combustion and smelting) and high pollution levels were found close to suburb industrial complexes, whereas pollution of Ba and Ca was mainly related to construction/demolition sources and was generally distributed homogeneously. The relatively minor contribution of non-exhaust traffic emissions to metal pollution in TR dusts was considered to be due to overwhelming industrial and construction/demolition contributions, as well as to the dilution effect of natural soil particles. Ingestion appears to be the major route of exposure for road dust for both adults and children, followed by dermal contact. The non-carcinogenic health risk resulting from exposure to the potentially toxic metals in TR dusts was within the safe level based on the Hazard Index (HI), except in pollution hotspots where exposure to Pb, Cr, and Cu may be hazardous to children. - Highlights: • Pollution and

  14. Pollution and health risk of potentially toxic metals in urban road dust in Nanjing, a mega-city of China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Enfeng, E-mail: efliu@niglas.ac.cn [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Yan, Ting [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Birch, Gavin [School of Geosciences, University of Sydney, Sydney, NSW 2006 (Australia); Zhu, Yuxin [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China)

    2014-04-01

    Spatial variations in concentrations of a suite of potentially toxic metals (Ba, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and Ca in road dusts (n = 99) from urban trunk roads (TR) in Nanjing, a mega-city in China, were established. Metal pollution levels, sources and human health risk (non-carcinogenic) were studied. In contrast to previous studies, we labeled the indicative metals relating to non-exhaust traffic emissions by comparing metal pollution between crossroad and park road dusts, and then anthropogenic sources of metals in TR dusts were assessed combining their spatial pollution patterns, principal component analysis and Pb isotopic compositions. Results showed that the metals were enriched in TR dusts compared to background soil concentrations with mean enrichment factors (EFs) of 2.2–23, indicating considerable anthropogenic influence. The degrees of metal pollution ranged from minimal to extremely high and ranked by Ca > Cu > Pb ≈ Zn > Cr ≈ Fe > Ni ≈ Ba > Mn on average. Pollution of Cr, Cu, Fe, Mn, Ni, Pb and Zn in TR dusts resulted primarily from industrial emissions (e.g., coal combustion and smelting) and high pollution levels were found close to suburb industrial complexes, whereas pollution of Ba and Ca was mainly related to construction/demolition sources and was generally distributed homogeneously. The relatively minor contribution of non-exhaust traffic emissions to metal pollution in TR dusts was considered to be due to overwhelming industrial and construction/demolition contributions, as well as to the dilution effect of natural soil particles. Ingestion appears to be the major route of exposure for road dust for both adults and children, followed by dermal contact. The non-carcinogenic health risk resulting from exposure to the potentially toxic metals in TR dusts was within the safe level based on the Hazard Index (HI), except in pollution hotspots where exposure to Pb, Cr, and Cu may be hazardous to children. - Highlights: • Pollution and

  15. Technetium and diazotrophic organisms: toxicity, localization, transfer factors

    International Nuclear Information System (INIS)

    Vandecasteele, C.M.; Delmotte, A.; Roucoux, P.; Hove, C. van

    1982-01-01

    Three diazotrophic organisms, together with one leguminous organism in symbiosis with one of them, were cultivated in the presence of various quantities of technetium, of which the localization, transfer factors and toxicity were studied in relation to the age of the organisms and their type of metabolism. The paper discusses the biochemical aspects of the results. (author)

  16. The influence of organic-containing soil dust on ice nucleation and cloud properties

    Science.gov (United States)

    Hummel, Matthias; Grini, Alf; Berntsen, Terje K.; Ekman, Annica

    2017-04-01

    Natural mineral dust from desert regions is known to be the most important contributor to atmospheric ice-nucleating particles (INP) which induce heterogeneous ice nucleation in mixed-phase clouds. Its ability to nucleate ice effectively is shown by various laboratory (Hoose and Möhler 2012) and field results (DeMott et al. 2015) and its abundance in ice crystal residuals has also been shown (Cziczo et al. 2013). Thus it is an important player when representing mixed-phase clouds in climate models. MODIS satellite data indicate that 1 /4 of the global dust emission originates from semi-arid areas rather than from arid deserts (Ginoux et al. 2012). Here, organic components can mix with minerals within the soil and get into the atmosphere. These so-called 'soil dust' particles are ice-nucleating active at high sub-zero temperatures, i.e. at higher temperatures than pure desert dust (Steinke et al. 2016). In this study, soil dust is incorporated into the Norwegian Earth System Model (NorESM, Bentsen et al. 2013) and applied to a modified ice nucleation parameterization (Steinke et al. 2016). Its influence on the cloud ice phase is evaluated by comparing a control run, where only pure desert dust is considered, and a sensitivity experiment, where a fraction of the dust emissions are classified as soil dust. Both simulations are nudged to ERA-interim meteorology and they have the same loading of dust emissions. NorESM gives a lower annual soil dust emission flux compared to Ginoux et al. (2012), but the desert dust flux is similar to the MODIS-retrieved data. Although soil dust concentrations are much lower than desert dust, the NorESM simulations indicate that the annual INP concentrations from soil dust are on average lower by a just a factor of 4 than INP concentrations from pure desert dust. The highest soil dust INP concentrations occur at a lower height than for desert dust, i.e at warmer temperatures inside mixed-phase clouds. Furthermore, soil dust INP

  17. Inhalation Toxicity of Ground Lunar Dust Prepared from Apollo-14 Soil

    Science.gov (United States)

    James, John T.; Lam, Chiu-wing; Scully, Robert R.; Cooper, Bonnie L.

    2011-01-01

    Within the decade one or more space-faring nations intend to return humans to the moon for more in depth exploration of the lunar surface and subsurface than was conducted during the Apollo days. The lunar surface is blanketed with fine dust, much of it in the respirable size range (<10 micron). Eventually, there is likely to be a habitable base and rovers available to reach distant targets for sample acquisition. Despite designs that could minimize the entry of dust into habitats and rovers, it is reasonable to expect lunar dust to pollute both as operations progress. Apollo astronauts were exposed briefly to dust at nuisance levels, but stays of up to 6 months on the lunar surface are envisioned. Will repeated episodic exposures to lunar dust present a health hazard to those engaged in lunar exploration? Using rats exposed to lunar dust by nose-only inhalation, we set out to investigate that question.

  18. Organic Matter Application Can Reduce Copper Toxicity in Tomato Plants

    Science.gov (United States)

    Campbell, Brian

    2010-01-01

    Copper fungicides and bactericides are often used in tomato cultivation and can cause toxic Cu levels in soils. In order to combat this, organic matter can be applied to induce chelation reactions and form a soluble complex by which much of the Cu can leach out of the soil profile or be taken up safely by plants. Organic acids such as citric,…

  19. Human health risk assessment based on toxicity characteristic leaching procedure and simple bioaccessibility extraction test of toxic metals in urban street dust of Tianjin, China.

    Directory of Open Access Journals (Sweden)

    Binbin Yu

    Full Text Available The potential ecological and human health risk related with urban street dust from urban areas of Tianjin, China was quantitatively analyzed using the method of toxicity characteristic leaching procedure (TCLP and simple bioaccessibility extraction test (SBET. In the study, Hakason index, Nemerow index (P, the hazard index (HI and the cancer risk index (RI were calculated to assess the potential risk. The sequence of potential ecological risk based on Hakason index was arsenic (As > cadmium (Cd > lead (Pb > copper (Cu > chromium (Cr, in particular, As and Cd were regarded as high polluted metals. While the results of extraction of TCLP were assessed using P, the sequence was As > Pb > Cd > Cr > Cu, which mean that As and Pb should be low polluted, and Cd, Cr and Cu would barely not polluted. For human health, total carcinogenic risk for children and adults was 2.01 × 10(-3 and 1.05 × 10(-3, respectively. This could be considered to be intolerable in urban street dust exposure. The sequence in the hazard quotient (HQ of each element was As > Cr > Pb > Cu > Cd. The HI value of these toxic metals in urban street dust for children and adults was 5.88 × 10(-1 and 2.80 × 10(-1, respectively. According to the characters of chemistry, mobility, and bioavailability of metals in urban street dust, we estimated the hazards on the environment and human health, which will help us to get more reasonable information for risk management of metals in urban environment.

  20. Temperature influence on chemical toxicity to aquatic organisms

    International Nuclear Information System (INIS)

    Cairns, J. Jr.; Heath, A.G.; Parker, B.C.

    1975-01-01

    The literature on the effects of temperature on chemical toxicity to aquatic animals and microorganisms is reviewed. Microbial photosynthesis and respiration is briefly discussed. It is concluded that there is a paucity of information on the inter-relations of temperature and toxicants to algae, bacteria, and protozoa and that standards based on the in situ response of indigenous organisms to specific discharge areas should be developed

  1. Neopterin: A candidate biomarker for the early assessment of toxicity of aluminum among bauxite dust exposed mine workers

    Science.gov (United States)

    Pingle, Shubhangi K.; Thakkar, Lucky R.; Jawade, Aruna A.; Tumane, Rajani G.; Jain, Ruchika K.; Soni, Pravin N.

    2015-01-01

    Introduction: Bauxite ore is a major source of aluminum (Al) which contains approximately 35–60% Al by weight. Occupational and environmental bauxite dust exposure may cause toxicity by interaction with human biological systems resulting in oxidative stress (OS) and cell death. A neopterin derivative as an antioxidant is able to modulate cytotoxicity by the induction of OS. Materials and Methods: A total of 273 subjects were selected for blood collection from three different major Al producing bauxite mines and were categorized into three groups as experimental (Exp) (n = 150), experimental controls (ExC) (n = 73) and control (Con) (n = 50). Whole blood and serum samples were used for measurement of Al, neopterin, urea and creatinine values. Statistical analysis was performed using R-2.15.1 programming language. Results and Discussion: The result showed that age, body mass index and the behavioral habits, that is, smoking, tobacco and alcohol consumption have possible effects on neopterin level. Serum neopterin levels were found to be significantly higher (P bauxite dust (even at low levels of Al) changes biochemical profile leading to high levels of serum neopterin. Levels of serum neopterin in workers exposed to bauxite dust were probably examined for the 1st time in India. The outcome of this study suggested that serum neopterin may be used as potential biomarker for early detection of health risks associated with bauxite dust exposed population. PMID:26500413

  2. Harmful influence of industrial dusts upon plants and animal organisms

    Energy Technology Data Exchange (ETDEWEB)

    Dziubek, T

    1967-01-01

    Contamination of the atmosphere near aluminum and copper foundries and phosphate fertilizer plants is caused mainly by fluorine compounds. The contamination damages plants, meadows, and pastures adjacent to factories or situated in the vicinity and has an indirect effect on domestic animals fed with fodder from such grasslands. Grassland vegetation 100-3000 m from the factories were investigated by measuring the quality and quantity of dust; 0-30 mg% fluorine compounds were found. Changes in cattle tissue (teeth and bones), a decrease in lactation, and a stunting of young animal growth were noted. A considerable decrease in the hemoglobin in the animals investigated also occurred.

  3. Lunar Dust and Lunar Simulant Activation, Monitoring, Solution and Cellular Toxicity Properties

    Science.gov (United States)

    Wallace, William; Jeevarajan, A. S.

    2009-01-01

    During the Apollo missions, many undesirable situations were encountered that must be mitigated prior to returning humans to the moon. Lunar dust (that part of the lunar regolith less than 20 microns in diameter) was found to produce several problems with mechanical equipment and could have conceivably produced harmful physiological effects for the astronauts. For instance, the abrasive nature of the dust was found to cause malfunctions of various joints and seals of the spacecraft and suits. Additionally, though efforts were made to exclude lunar dust from the cabin of the lunar module, a significant amount of material nonetheless found its way inside. With the loss of gravity correlated with ascent from the lunar surface, much of the finer fraction of this dust began to float and was inhaled by the astronauts. The short visits tothe Moon during Apollo lessened exposure to the dust, but the plan for future lunar stays of up to six months demands that methods be developed to minimize the risk of dust inhalation. The guidelines for what constitutes "safe" exposure will guide the development of engineering controls aimed at preventing the presence of dust in the lunar habitat. This work has shown the effects of grinding on the activation level of lunar dust, the changes in dissolution properties of lunar simulant, and the production of cytokines by cellular systems. Grinding of lunar dust leads to the production of radicals in solution and increased dissolution of lunar simulant in buffers of different pH. Additionally, ground lunar simulant has been shown to promote the production of IL-6 and IL-8, pro-inflammatory cytokines, by alveolar epithelial cells. These results provide evidence of the need for further studies on these materials prior to returning to the lunar surface.

  4. Phytoremediation of Toxic Elemental and Organic Pollutants

    International Nuclear Information System (INIS)

    Meagher, Richard B.

    2000-01-01

    Phytoremediation is the use of plants to extract, sequester, and/or detoxify pollutants. Phytoremediation is widely viewed as the ecologically responsible alternative to the environmentally destructive physical remediation methods currently practiced. Plants have many endogenous genetic, biochemical, and physiological properties that make them ideal agents for soil and water remediation. Significant progress has been made in recent years in developing native or genetically modified plants for the remediation of environmental contaminants. Because elements are immutable, phytoremediation strategies for radionuclide and heavy metal pollutants focus on hyperaccumulation above-ground. In contrast, organic pollutants can potentially be completely mineralized by plants

  5. Assessing toxicity of varying major ion concentrations to marine organisms

    International Nuclear Information System (INIS)

    Mount, D.R.; Quast, W.

    1993-01-01

    Recent regulatory developments have required that produced waters discharged in the Gulf of Mexico be monitored for toxicity to marine organisms. While produced water may contain a variety of indigenous and introduced chemicals, virtually all have moderate to high concentrations of major ions. Although seawater is also rich in these ions, excessive salinity can cause toxicity to marine organisms. Perhaps more importantly, toxicity to marine organisms can be caused by deviations from normal ion ratios even if the total salinity is within organism tolerances. To provide a better understanding of marine organism responses to variations in major ion concentrations, the authors conducted a series of laboratory experiments to quantify the responses of mysid shrimp (Mysidopsis bahia) and sheepshead minnows (Cyprinodon variegatus) to modifications of normal seawater chemistry. Acute testing included both increasing and decreasing the concentrations of individual ions relative to seawater, as well as altering total salinity. Results show these organisms can be adversely affected by this altered chemistry and their sensitivity is dependent upon the individual ions that are manipulated. Results from these studies are being incorporated into an overall strategy for evaluating the influence of major ion chemistry on produced water toxicity tests

  6. Impact of Saw Dust Application on the Distribution of Potentially Toxic Metals in Contaminated Soil.

    Science.gov (United States)

    Awokunmi, Emmmanuel E

    2017-12-01

    The need to develop an approach for the reclamation of contaminated site using locally available agricultural waste has been considered. The present study investigated the application of sawdust as an effective amendment in the immobilization of potentially toxic metals (PTMs) by conducting a greenhouse experiment on soil collected from an automobile dumpsite. The amended and non-amended soil samples were analyzed for their physicochemical parameters and sequential extraction of PTMs. The results revealed that application of amendment had positive impact on the physicochemical parameters as organic matter content and cation exchange capacity increased from 12.1% to 12.8% and 16.4 to 16.8 meq/100 g respectively. However, the mobility and bioavalability of these metals was reduced as they were found to be distributed mostly in the non-exchangeable phase of soil. Therefore, application of sawdust successfully immobilized PTMs and could be applied for future studies in agricultural soil reclamation.

  7. Saharan dust - a carrier of persistent organic pollutants, metals and microbes to the Caribbean?

    Directory of Open Access Journals (Sweden)

    V.H Garrison

    2006-12-01

    Full Text Available An international team of scientists from government agencies and universities in the United States, U.S. Virgin Islands (USVI, Trinidad & Tobago, the Republic of Cape Verde, and the Republic of Mali (West Africa is working together to elucidate the role Saharan dust may play in the degradation of Caribbean ecosystems. The first step has been to identify and quantify the persistent organic pollutants (POPs, trace metals, and viable microorganisms in the atmosphere in dust source areas of West Africa, and in dust episodes at downwind sites in the eastern Atlantic (Cape Verde and the Caribbean (USVI and Trinidad & Tobago. Preliminary findings show that air samples from Mali contain a greater number of pesticides, polychlorinated biphenyls (PCBs and polycyclic aromatic hydrocarbons (PAHs and in higher concentrations than the Caribbean sites. Overall, POP concentrations were similar in USVI and Trinidad samples. Trace metal concentrations were found to be similar to crustal composition with slight enrichment of lead in Mali. To date, hundreds of cultureable micro-organisms have been identified from Mali, Cape Verde, USVI, and Trinidad air samples. The sea fan pathogen, Aspergillus sydowii, has been identified in soil from Mali and in air samples from dust events in the Caribbean. We have shown that air samples from a dust-source region contain orders of magnitude more cultureable micro-organisms per volume than air samples from dust events in the Caribbean, which in turn contain 3-to 4-fold more cultureable microbes than during non-dust conditions. Rev. Biol. Trop. 54 (Suppl. 3: 9-21. Epub 2007 Jan. 15.

  8. Comparative toxicity of ten organic chemicals to four earthworm species

    Energy Technology Data Exchange (ETDEWEB)

    Neuhauser, E.F.; Durkin, P.R.; Malecki, M.R.; Anatra, M.

    1986-01-01

    Ten organic chemicals were tested for toxicity to four earthworm species: Allolobophora tuberculata, Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus, using the European Economic Community's (EEC) earthworm artificial soil and contact testing procedure. The phenols were the most toxic chemicals tested, followed by the amine, substituted benzenes, halogenated aliphatic hydrocarbon, polycyclic aromatic hydrocarbon and phthalate as the least toxic chemical tested. Correlations among species within each type of test for a given chemical were extremely high, suggesting that the selection of earthworm test species does not markedly affect the assessment of a chemical's toxicity. The correlation between the two tests was low for all test species. The contact test LC50 for a given chemical cannot be directly correlated to an artificial soil test LC50 for the same earthworm species.

  9. Toxicity, Bioaccumulation and Biotransformation of Silver Nanoparticles in Marine Organisms

    Science.gov (United States)

    The toxicity, bioaccumulation and biotransformation of citrate and polyvinylpyrrolidone (PVP) capped silver nanoparticles (NPs) (AgNP-citrate and AgNP-PVP) and titanium dioxide (TiO2) NPs in marine organisms via marine sediment exposure were investigated. Results from 7-d sedimen...

  10. Acute toxicity of birch tar oil on aquatic organisms

    Directory of Open Access Journals (Sweden)

    M. HAGNER

    2008-12-01

    Full Text Available Birch tar oil (BTO is a by-product of processing birch wood in a pyrolysis system. Accumulating evidence suggests the suitability of BTO as a biocide or repellent in terrestrial environments for the control of weeds, insects, molluscs and rodents. Once applied as biocide, BTO may end up, either through run-off or leaching, in aquatic systems and may have adverse effects on non-target organisms. As very little is known about the toxicity of BTO to aquatic organisms, the present study investigated acute toxicity (LC50/EC50 of BTO for eight aquatic organisms. Bioassays with the Asellus aquaticus (crustacean, Lumbriculus variegatus (oligochaeta worm, Daphnia magna (crustacean, Lymnea sp. (mollusc, Lemna minor (vascular plant, Danio rerio (fish, Scenedesmus gracilis (algae, and Vibrio fischeri (bacterium were performed according to ISO, OECD or USEPA-guidelines. The results indicated that BTO was practically nontoxic to most aquatic organisms as the median effective BTO concentrations against most organisms were >150 mg L-1. In conclusion, our toxicity tests showed that aquatic organisms are to some extent, invariably sensitive to birch tar oil, but suggest that BTO does not pose a severe hazard to aquatic biota. We deduce that, unless BTOs are not applied in the immediate vicinity of water bodies, no special precaution is required.;

  11. Comparative toxicity in rats vs hamsters of inhaled radon daughters with and without uranium ore dust

    International Nuclear Information System (INIS)

    Gaven, J.C.; Palmer, R.F.; McDonald, K.E.; Lund, J.E.; Stuart, B.O.

    1977-01-01

    Simultaneous exposures of rats and hamsters to inhaled radon daughters, with and without uranium ore dust, were performed daily for five months. Pulmonary pathology developing in 6 to 13 mo after cessation of daily exposures included interstitial fibrosis, emphysema, epithelial hyperplasia, squamous metaplasia, and malignant neoplasia. Rats showed a greater variety and more severe response to these uranium mine inhalation exposures than did hamsters. Inhalation of radon daughters with uranium ore dust displayed the site of greatest damage, including squamous carcinoma, from the nasopharynx to the lungs. Sixty percent of the rats exposed to radon daughters with ore dust developed primary pulmonary carcinomas, providing an appropriate short-term experimental animal model for investigation of respiratory tract carcinogenesis in uranium miners

  12. The effect of organic coating on the heterogeneous ice nucleation efficiency of mineral dust aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Moehler, O; Benz, S; Saathoff, H; Schnaiter, M; Wagner, R [Forschungszentrum Karlsruhe, Institute for Meteorology and Climate Research, 76021 Karlsruhe (Germany); Schneider, J; Walter, S [Max Planck Institute for Chemistry, 55128 Mainz (Germany); Ebert, V; Wagner, S [University of Heidelberg, Institute for Physical Chemistry, 69120 Heidelberg (Germany)], E-mail: Ottmar.Moehler@imk.fzk.de

    2008-04-15

    The effect of organic coating on the heterogeneous ice nucleation (IN) efficiency of dust particles was investigated at simulated cirrus cloud conditions in the AIDA cloud chamber of Forschungszentrum Karlsruhe. Arizona test dust (ATD) and the clay mineral illite were used as surrogates for atmospheric dust aerosols. The dry dust samples were dispersed into a 3.7 m{sup 3} aerosol vessel and either directly transferred into the 84 m{sup 3} cloud simulation chamber or coated before with the semi-volatile products from the reaction of {alpha}-pinene with ozone in order to mimic the coating of atmospheric dust particles with secondary organic aerosol (SOA) substances. The ice-active fraction was measured in AIDA expansion cooling experiments as a function of the relative humidity with respect to ice, RHi, in the temperature range from 205 to 210 K. Almost all uncoated dust particles with diameters between 0.1 and 1.0 {mu}m acted as efficient deposition mode ice nuclei at RHi between 105 and 120%. This high ice nucleation efficiency was markedly suppressed by coating with SOA. About 20% of the ATD particles coated with a SOA mass fraction of 17 wt% were ice-active at RHi between 115 and 130%, and only 10% of the illite particles coated with an SOA mass fraction of 41 wt% were ice-active at RHi between 160 and 170%. Only a minor fraction of pure SOA particles were ice-active at RHi between 150 and 190%. Strong IN activation of SOA particles was observed only at RHi above 200%, which is clearly above water saturation at the given temperature. The IN suppression and the shift of the heterogeneous IN onset to higher RHi seem to depend on the coating thickness or the fractional surface coverage of the mineral particles. The results indicate that the heterogeneous ice nucleation potential of atmospheric mineral particles may also be suppressed if they are coated with secondary organics.

  13. The effect of organic coating on the heterogeneous ice nucleation efficiency of mineral dust aerosols

    International Nuclear Information System (INIS)

    Moehler, O; Benz, S; Saathoff, H; Schnaiter, M; Wagner, R; Schneider, J; Walter, S; Ebert, V; Wagner, S

    2008-01-01

    The effect of organic coating on the heterogeneous ice nucleation (IN) efficiency of dust particles was investigated at simulated cirrus cloud conditions in the AIDA cloud chamber of Forschungszentrum Karlsruhe. Arizona test dust (ATD) and the clay mineral illite were used as surrogates for atmospheric dust aerosols. The dry dust samples were dispersed into a 3.7 m 3 aerosol vessel and either directly transferred into the 84 m 3 cloud simulation chamber or coated before with the semi-volatile products from the reaction of α-pinene with ozone in order to mimic the coating of atmospheric dust particles with secondary organic aerosol (SOA) substances. The ice-active fraction was measured in AIDA expansion cooling experiments as a function of the relative humidity with respect to ice, RHi, in the temperature range from 205 to 210 K. Almost all uncoated dust particles with diameters between 0.1 and 1.0 μm acted as efficient deposition mode ice nuclei at RHi between 105 and 120%. This high ice nucleation efficiency was markedly suppressed by coating with SOA. About 20% of the ATD particles coated with a SOA mass fraction of 17 wt% were ice-active at RHi between 115 and 130%, and only 10% of the illite particles coated with an SOA mass fraction of 41 wt% were ice-active at RHi between 160 and 170%. Only a minor fraction of pure SOA particles were ice-active at RHi between 150 and 190%. Strong IN activation of SOA particles was observed only at RHi above 200%, which is clearly above water saturation at the given temperature. The IN suppression and the shift of the heterogeneous IN onset to higher RHi seem to depend on the coating thickness or the fractional surface coverage of the mineral particles. The results indicate that the heterogeneous ice nucleation potential of atmospheric mineral particles may also be suppressed if they are coated with secondary organics

  14. Electron beam treatment of toxic volatile organic compounds and dioxins

    International Nuclear Information System (INIS)

    Kojima, Takuji

    2006-01-01

    Considerations of wastes based on the reduction, reuse and recycle in daily life are primary measures to conserve our environment, but the control technology is necessary to support these measures. The electron beam (EB) process is promising as an advanced purification process having advantages such as a quick treatment of big volume gas, applicability even for very low concentration pollutants as the further purification at the downstream of existing process, and decomposition of pollutants into non-toxic substances by one process. The EB technology has been developed for treatment of toxic volatile organic compounds (VOCs) in ventilation gas and dioxins in solid waste incineration flue gas. (author)

  15. Health effects of exposure to organic dust in workers of a modern hatchery.

    Science.gov (United States)

    Skórska, Czesława; Mackiewicz, Barbara; Golec, Marcin; Cholewa, Grazyna; Chmielowiec-Korzeniowska, Anna; Dutkiewicz, Jacek

    2007-01-01

    The aim of the presented study was to determine the health status of workers occupationally exposed to moderate amounts of organic dust, employed in a modern hatchery with an efficient ventilation system. A group of 32 hatchery workers was examined. As a reference group, 50 urban dwellers not exposed to any kind of organic dust were examined. All people were interviewed for the presence of work-related symptoms and subjected to physical and spirometric examinations. Blood sera were examined for the presence of precipitins against 13 antigens associated with organic dust, and for the presence of total and chicken-specific No significant differences were found between the spirometric values in the group of hatchery workers and the reference group. Positive precipitin reactions were noted mostly with the antigens of Gram-negative bacteria associated with organic dust. The frequencies of positive reactions to antigens of Escherichia coli and Acinetobacter baumannii in hatchery workers were significantly greater compared to the reference group (phatchery workers were significantly greater compared to the reference group (phatchery workers was nearly 3 times greater compared to the reference group, and the difference proved to be statistically significant (pchicken feathers were detected in the blood of hatchery workers and referents. In conclusion, the examined hatchery workers showed a moderate frequency of work-related symptoms, no decline in lung function and low reactivity to most microbial and bird protein allergens. These results suggest that the effects of exposure to organic dust in workers of modern hatcheries with an efficient ventilation system are less compared to the workers of poultry farms, such as broiler or egg laying houses.

  16. Mechanism and Modelling for Sorption of Toxic Ion on Cement Kiln Dust

    International Nuclear Information System (INIS)

    EI- Dakroury, A.; Sayed, M.S.; EL- Sherif, E.

    2009-01-01

    Cement manufacturing is a critically important industry in Egypt. These industrial by-product and waste materials must be managed responsibly to insure a clean and safe environment. Cement kiln dust (CKD) is a significant by-product material of the cement manufacturing process. Cement kiln dust is a waste residue composed chiefly of oxidized, anhydrous, micron - sized particles generated as a by product of the manufacture of Portland cement. The use of cement kiln dust as adsorbent in wastewater treatment has a great attention as cheap material and clay structure. This work will discuss the basic characteristics of CKD physical and chemical properties and regulatory requirements: The batch removal of Cr(VI) from aqueous solution using low cost adsorbents such as cement kiln dust under different experimental conditions. The influences of initial Cr (VI) ion concentration (20 to 300 mg1-1) and ph (1 to 4) were investigated in this study. Adsorption of Cr (VI) is highly ph-dependent and the results indicate that the optimum ph for the removal was found to be 1 for CKD. A comparison of kinetic models applied to the adsorption of Cr (VI) ions on the CKD was evaluated for the pseudo first order, the pseudo second-order, Elovich and intra particle diffusion kinetic models, respectively. The results showed that the pseudo second-order kinetic model was found to correlate the experimental data well

  17. Effect of atmospheric organic complexation on iron-bearing dust solubility

    OpenAIRE

    Paris , R.; Desboeufs , K. V.

    2013-01-01

    International audience; Recent studies reported that the effect of organic complexation may be a potentially important process to be considered by models estimating atmospheric iron flux to the ocean. In this study, we investigated this process effect by a series of dissolution experiments on iron-bearing dust in the presence or the absence of various organic compounds (acetate, formate, oxalate, malonate, succinate, glutarate, glycolate, lactate, tartrate and humic acid as an analogue of hum...

  18. Nonvolatile organic pollutants in domestic dust samples from the urban Hamburg area; Schwerfluechtige organische Umweltchemikalien in Hamburger Hausstaeuben

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    Nonvolatile organic pollutants were measured in 65 private apartments, i.e. biocides, softeners, flame protection agents, stabilisers, soot, tar and bitumen which are contained in many everyday products and building materials. The homes were the private homes of staff members of the Hamburg Environmental Office and their friends; none of the homes were problem cases. The information was obtained by collecting vacuum cleaner dust. The inhomogeneous dust was screened, and the < 63 {mu}m fraction was analyzed. This fraction was homogeneously enough to provide reproducible results. Chloroparaffins and organic tin compounds were measured for the first time ever in this project. While the concentrations of chloroparaffins were significant, organic tin compounds are rather scarce. Bis(2,ethylhexyl)phthalate (DEHP) was the main component in nearly all household dust samples. Phthalates in general had the highest concentrations. Next to phthalates, chloroparaffins and the biocide permethrin were found in high concentrations, followed by organic phosphates, further biocides, organic tin compounds and benzo(a)pyrene. The individual substances wre assessed on the basis of 95 percent percentiles obtained from the measured frequency distributions. This figure means that 95 percent of the household dust have a lower or equal concentration than the 95 percent percentile. 95 percent percentiles are generally used as reference values in environmental measurements. The reference values presented here should be considered as preliminary values, owing to the fact that the apartments are not representative of the city of Hamburg, and 65 dust samples are too small a data base. Among the most important substances, owing to their high concentrations and/or toxic effects, are DEHP with a preliminary reference value of 1600 mg/kg of household dust, dibutyl phthalate with 180 mg/kg of dust, short-chain chloroparaffins with 180 mg/kg of dust, permethrin with 110 mg/kg of dust, monobutyl tin

  19. Linkage of genomic biomarkers to whole organism endpoints in a Toxicity Identification Evaluation (TIE).

    Science.gov (United States)

    Aquatic organisms are exposed to many toxic chemicals and interpreting the cause and effect relationships between occurrence and impairment is difficult. Toxicity Identification Evaluation (TIE) provides a systematic approach for identifying responsible toxicants. TIE relies on ...

  20. USE OF POWDERED COCONUT CHARCOAL AS A TOXICITY IDENTIFICATION AND EVALUATION MANIPULATION FOR ORGANIC TOXICANTS IN MARINE SEDIMENTS

    Science.gov (United States)

    We report on a procedure using powdered coconut charcoal to sequester organic contaminants and reduce toxicity in sediments as part of a series of toxicity identification and evaluation (TIE) methods. Powdered coconut charcoal (PCC) was effective in reducing the toxicity of endos...

  1. Toxicity of selected organic chemicals to the earthworm Eisenia fetida

    Energy Technology Data Exchange (ETDEWEB)

    Neuhauser, E.F.; Loehr, R.C.; Malecki, M.R.; Milligan, D.L.; Durkin, P.R.

    A number of methods recently have been developed to biologically evaluate the impact of man's activities on soil ecosystems. Two test methods, the 2-d contact test and the 14-d artificial soil test, were used to evaluate the impact of six major classes of organic chemicals on the earthworm Eisenia fetida (Savigny). Of the organic chemicals tested, phenols and amines were the most toxic to the worms, followed in descending order of toxicity by the substituted aromatics, halogenated aliphatics, polycyclic aromatic hydrocarbons, and phthalates. No relationship was found between earthworm toxicity as determined by the contact test and rat, Rattus norvegicus Berkenhout and mouse, Mus musculus L. LD/sub 50/ values. The physicochemical parameters of water solubility, vapor pressure, and octanol/water partition coefficient for the chemicals tested in the contact test did not show a significant relationship to the E. fetida LC/sub 50/ values. These studies indicate that: (i) earthworms can be a suitable biomonitoring tool to assist in measuring the impact of organic chemicals in wastes added to soils and (ii) contact and artificial soil tests can be useful in measuring biological impacts.

  2. Multi-Organ toxicity demonstration in a functional human in vitro system composed of four organs.

    Science.gov (United States)

    Oleaga, Carlota; Bernabini, Catia; Smith, Alec S T; Srinivasan, Balaji; Jackson, Max; McLamb, William; Platt, Vivien; Bridges, Richard; Cai, Yunqing; Santhanam, Navaneetha; Berry, Bonnie; Najjar, Sarah; Akanda, Nesar; Guo, Xiufang; Martin, Candace; Ekman, Gail; Esch, Mandy B; Langer, Jessica; Ouedraogo, Gladys; Cotovio, Jose; Breton, Lionel; Shuler, Michael L; Hickman, James J

    2016-02-03

    We report on a functional human model to evaluate multi-organ toxicity in a 4-organ system under continuous flow conditions in a serum-free defined medium utilizing a pumpless platform for 14 days. Computer simulations of the platform established flow rates and resultant shear stress within accepted ranges. Viability of the system was demonstrated for 14 days as well as functional activity of cardiac, muscle, neuronal and liver modules. The pharmacological relevance of the integrated modules were evaluated for their response at 7 days to 5 drugs with known side effects after a 48 hour drug treatment regime. The results of all drug treatments were in general agreement with published toxicity results from human and animal data. The presented phenotypic culture model exhibits a multi-organ toxicity response, representing the next generation of in vitro systems, and constitutes a step towards an in vitro "human-on-a-chip" assay for systemic toxicity screening.

  3. Research of nickel nanoparticles toxicity with use of Aquatic Organisms

    International Nuclear Information System (INIS)

    Morgaleva, T; Morgalev, Yu; Gosteva, I; Morgalev, S

    2015-01-01

    The effect of nanoparticles with the particle size Δ 50 =5 nm on the test function of aquatic organisms was analyzed by means of biotesting methods with the use of a complex of test-organisms representing general trophic levels. The dependence of an infusoria Paramecium caudatum chemoattractant-elicited response, unicellular algae Chlorella vulgaris Beijer growth rate, Daphnia magna Straus mortality and trophic activity and Danio rerio fish kill due to nNi disperse system concentration, is estimated. It is determined that the release of chlorella into cultivated environment including nNi as a feed for daphnias raises the death rate of entomostracans. The minimal concentration, whereby an organism response to the effect of nNi is registered, depends on the type of test organism and the analysed test function. L(E)C 20 is determined for all the organisms used in bioassays. L(E)C 50 is estimated for Paramecium caudatum (L(E)C 50 = 0.0049 mg/l), for Chlorella vulgaris Beijer (L(E)C 50 = 0.529 mg/l), for Daphnia m. S (L(E)C 50 > 100 mg/l) and for fish Danio rerio (L(E)C 50 > 100 mg/l). According to the Globally Harmonized System hazard substance evaluation criteria and Commission Directive 93/67/EEC, nNi belongs to the “acute toxicity 1” category of toxic substances. (paper)

  4. Research of nickel nanoparticles toxicity with use of Aquatic Organisms

    Science.gov (United States)

    Morgaleva, T.; Morgalev, Yu; Gosteva, I.; Morgalev, S.

    2015-11-01

    The effect of nanoparticles with the particle size Δ50=5 nm on the test function of aquatic organisms was analyzed by means of biotesting methods with the use of a complex of test-organisms representing general trophic levels. The dependence of an infusoria Paramecium caudatum chemoattractant-elicited response, unicellular algae Chlorella vulgaris Beijer growth rate, Daphnia magna Straus mortality and trophic activity and Danio rerio fish kill due to nNi disperse system concentration, is estimated. It is determined that the release of chlorella into cultivated environment including nNi as a feed for daphnias raises the death rate of entomostracans. The minimal concentration, whereby an organism response to the effect of nNi is registered, depends on the type of test organism and the analysed test function. L(E)C20 is determined for all the organisms used in bioassays. L(E)C50 is estimated for Paramecium caudatum (L(E)C50 = 0.0049 mg/l), for Chlorella vulgaris Beijer (L(E)C50 = 0.529 mg/l), for Daphnia m. S (L(E)C50 > 100 mg/l) and for fish Danio rerio (L(E)C50 > 100 mg/l). According to the Globally Harmonized System hazard substance evaluation criteria and Commission Directive 93/67/EEC, nNi belongs to the “acute toxicity 1” category of toxic substances.

  5. Effect of atmospheric organic complexation on iron-bearing dust solubility

    Directory of Open Access Journals (Sweden)

    R. Paris

    2013-05-01

    Full Text Available Recent studies reported that the effect of organic complexation may be a potentially important process to be considered by models estimating atmospheric iron flux to the ocean. In this study, we investigated this process effect by a series of dissolution experiments on iron-bearing dust in the presence or the absence of various organic compounds (acetate, formate, oxalate, malonate, succinate, glutarate, glycolate, lactate, tartrate and humic acid as an analogue of humic like substances, HULIS typically found in atmospheric waters. Only 4 of tested organic ligands (oxalate, malonate, tartrate and humic acid caused an enhancement of iron solubility which was associated with an increase of dissolved Fe(II concentrations. For all of these organic ligands, a positive linear dependence of iron solubility to organic concentrations was observed and showed that the extent of organic complexation on iron solubility decreased in the following order: oxalate >malonate = tartrate > humic acid. This was attributed to the ability of electron donors of organic ligands and implies a reductive ligand-promoted dissolution. This study confirms that among the known atmospheric organic binding ligands of Fe, oxalate is the most effective ligand promoting dust iron solubility and showed, for the first time, the potential effect of HULIS on iron dissolution under atmospheric conditions.

  6. Toxicity of organic supplies for the egg parasitoid Telenomus podisi

    Directory of Open Access Journals (Sweden)

    Débora Mello da Silva

    2014-01-01

    Full Text Available Toxicity (dosage per hectare of: 1 Baculovirus anticarsia 140x109 cpi; 2 Bacillus thuringiensis 16.8g; 3 Azadirachtin-A, azadirachtin-B, nimbina and salamina 9.6 ppm; 4 Rotenoids 4 liters; 5 Nitrogen 1.3%, phosphorus 3.0% and total organic carbon 8.0% 3 liters; 6 Sodium silicate 2% 4 liters; 7 Copper 7% + calcium 3.3% 1.8 liters; 8 Sulfur 20% + quicklime 10% 1.8 liters; 9 Chlorpyrifos 384g; 10 Distilled H2O (control were evaluated for pupae and adults of Telenomus podisi. Treatments from 1 to 8 were in general harmless (class 1 to both pupae and adults of T. podisi. Among them, only treatment 5 and 7 presented slightly toxic to the parasitoid with a reduction in parasitism 5 days after F1 parasitoid emergence. Differently, the chlorpyrifos was classified as slightly harmful (class 2 or moderately harmful (class 3. Therefore, the use of the tested organic agricultural supplies in the production of organic soybean is viable, without impairing the natural biological control allowed by this egg parasitoid. Chlorpyrifos use, on the other hand, is not allowed in organic soybean, but even on convention crop production, could whenever possible, be replaced by other products more compatible with T. podisi preservation.

  7. Flow characteristics of bounded self-organized dust vortex in a complex plasma

    Science.gov (United States)

    Laishram, Modhuchandra; Sharma, D.; Chattopdhyay, P. K.; Kaw, P. K.

    2018-01-01

    Dust clouds are often formed in many dusty plasma experiments, when micron size dust particles introduced in the plasma are confined by spatial non-uniformities of the potential. These formations show self-organized patterns like vortex or circulation flows. Steady-state equilibrium dynamics of such dust clouds is analyzed by 2D hydrodynamics for varying Reynolds number, Re, when the cloud is confined in an azimuthally symmetric cylindrical setup by an effective potential and is in a dynamic equilibrium with an unbounded sheared plasma flow. The nonconservative forcing due to ion flow shear generates finite vorticity in the confined dust clouds. In the linear limit (Re ≪ 1), the collective flow is characterized by a single symmetric and elongated vortex with scales correlating with the driving field and those generated by friction with the boundaries. However in the high Re limit, (Re ≥ 1), the nonlinear inertial transport (u . ∇u) is effective and the vortex structure is characterized by an asymmetric equilibrium and emergence of a circular core region with uniform vorticity, over which the viscous stress is negligible. The core domain is surrounded by a virtual boundary of highly convective flow followed by thin shear layers filled with low-velocity co- and counter-rotating vortices, enabling the smooth matching with external boundary conditions. In linear regime, the effective boundary layer thickness is recovered to scale with the dust kinematic viscosity as Δr ≈ μ1/3 and is modified as Δr ≈ (μL∥/u)1/2 in the nonlinear regime through a critical kinematic viscosity μ∗ that signifies a structural bifurcation of the flow field solutions. The flow characteristics recovered are relevant to many microscopic biological processes at lower Re, as well as gigantic vortex flows such as Jovian great red spot and white ovals at higher Re.

  8. An analysis of employee exposure to organic dust at large-scale composting facilities

    Science.gov (United States)

    Sykes, P.; Allen, J. A.; Wildsmith, J. D.; Jones, K. P.

    2009-02-01

    with inhalation of organic dusts at composting sites.

  9. Health hazards of cement dust

    International Nuclear Information System (INIS)

    Meo, Sultan A.

    2004-01-01

    ven in the 21st century, millions of people are working daily in a dusty environment. They are exposed to different types of health hazards such as fume, gases and dust, which are risk factors in developing occupational disease. Cement industry is involved in the development of structure of this advanced and modern world but generates dust during its production. Cement dust causes lung function impairment, chronic obstructive lung disease, restrictive lung disease, pneumoconiosis and carcinoma of the lungs, stomach and colon. Other studies have shown that cement dust may enter into the systemic circulation and thereby reach the essentially all the organs of body and affects the different tissues including heart, liver, spleen, bone, muscles and hairs and ultimately affecting their micro-structure and physiological performance. Most of the studies have been previously attempted to evaluate the effects of cement dust exposure on the basis of spirometry or radiology, or both. However, collective effort describing the general effects of cement dust on different organ and systems in humans or animals, or both has not been published. Therefore, the aim of this review is to gather the potential toxic effects of cement dust and to minimize the health risks in cement mill workers by providing them with information regarding the hazards of cement dust. (author)

  10. THE REINCARNATION OF INTERSTELLAR DUST: THE IMPORTANCE OF ORGANIC REFRACTORY MATERIAL IN INFRARED SPECTRA OF COMETARY COMAE AND CIRCUMSTELLAR DISKS

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Hiroshi, E-mail: hiroshi_kimura@cps-jp.org [Graduate School of Science, Kobe University, c/o CPS (Center for Planetary Science), Chuo-ku Minatojima Minamimachi 7-1-48, Kobe 650-0047 (Japan)

    2013-09-20

    We consider the reincarnation of interstellar dust to be reborn in protoplanetary disks as aggregates consisting of submicron-sized grains with a crystalline or amorphous silicate core and an organic-rich carbonaceous mantle. We find that infrared spectra of reincarnated interstellar dust reproduce emission peaks at correct wavelengths where the peaks were observed in cometary comae, debris disks, and protoplanetary disks if the volume fraction of organic refractory meets the constraints on elemental abundances. We discuss what we can learn from the infrared spectra of reincarnated interstellar dust in cometary comae and circumstellar disks.

  11. The Reincarnation of Interstellar Dust: The Importance of Organic Refractory Material in Infrared Spectra of Cometary Comae and Circumstellar Disks

    Science.gov (United States)

    Kimura, Hiroshi

    2013-09-01

    We consider the reincarnation of interstellar dust to be reborn in protoplanetary disks as aggregates consisting of submicron-sized grains with a crystalline or amorphous silicate core and an organic-rich carbonaceous mantle. We find that infrared spectra of reincarnated interstellar dust reproduce emission peaks at correct wavelengths where the peaks were observed in cometary comae, debris disks, and protoplanetary disks if the volume fraction of organic refractory meets the constraints on elemental abundances. We discuss what we can learn from the infrared spectra of reincarnated interstellar dust in cometary comae and circumstellar disks.

  12. THE REINCARNATION OF INTERSTELLAR DUST: THE IMPORTANCE OF ORGANIC REFRACTORY MATERIAL IN INFRARED SPECTRA OF COMETARY COMAE AND CIRCUMSTELLAR DISKS

    International Nuclear Information System (INIS)

    Kimura, Hiroshi

    2013-01-01

    We consider the reincarnation of interstellar dust to be reborn in protoplanetary disks as aggregates consisting of submicron-sized grains with a crystalline or amorphous silicate core and an organic-rich carbonaceous mantle. We find that infrared spectra of reincarnated interstellar dust reproduce emission peaks at correct wavelengths where the peaks were observed in cometary comae, debris disks, and protoplanetary disks if the volume fraction of organic refractory meets the constraints on elemental abundances. We discuss what we can learn from the infrared spectra of reincarnated interstellar dust in cometary comae and circumstellar disks

  13. Occupational agriculture organic dust exposure and its relationship to asthma and airway inflammation in adults.

    Science.gov (United States)

    Wunschel, Javen; Poole, Jill A

    2016-06-01

    Recent studies have made advances into understanding the complex agriculture work exposure environment in influencing asthma in adults. The objective of this study is to review studies of occupational agricultural exposures including dust, animal, and pesticide exposures with asthma in adult populations. PubMed databases were searched for articles pertaining to farming, agriculture, asthma, occupational asthma, airway inflammation, respiratory disease, lung disease, pesticides, and organic dust. Studies chosen were published in or after 1999 that included adults and asthma and farming/agricultural work or agricultural exposures and airway inflammatory disease measurements. The data remain inconclusive. Several retrospective studies demonstrate agricultural work to be protective against asthma in adults, especially with increased farming exposure over time. In contrast, other studies find increased risk of asthma with farming exposures, especially for the non-atopic adult. Mechanistic and genetic studies have focused on defining the wide variety and abundance of microorganisms within these complex organic dusts that trigger several pattern recognition receptor pathways to modulate the hosts' response. Asthma risk depends on the interplay of genetic factors, gender, atopic predisposition, type of livestock, pesticide exposure, and magnitude and duration of exposure in the adult subject. Longer exposure to occupational farming is associated with decreased asthma risk. However, studies also suggest that agricultural work and multiple types of livestock are independent risk factors for developing asthma. Prospective and longitudinal studies focusing on genetic polymorphisms, objective assessments, and environmental sampling are needed to further delineate the influence of agriculture exposure in the adult worker.

  14. Perspectives of experimental and theoretical studies of self-organized dust structures in complex plasmas under microgravity conditions

    International Nuclear Information System (INIS)

    Tsytovich, V N

    2015-01-01

    We review research aimed at understanding the phenomena occurring in a complex plasma under microgravity conditions. Some aspects of the work already performed are considered that have not previously been given sufficient attention but which are potentially crucial for future work. These aspects, in particular, include the observation of compact dust structures that are estimated to be capable of confining all components of a dust plasma in a bounded spatial volume; experimental evidence of the nonlinear screening of dust particles; and experimental evidence of the excitation of collective electric fields. In theoretical terms, novel collective attraction processes between likely charged dust particles are discussed and all schemes of the shadowy attraction between dust particles used earlier, including in attempts to interpret observations, are reviewed and evaluated. Dust structures are considered from the standpoint of the current self-organization theory. It is emphasized that phase transitions between states of self-organized systems differ significantly from those in homogeneous states and that the phase diagrams should be constructed in terms of the parameters of a self-organized structure and cannot be constructed in terms of the temperature and density or similar parameters of homogeneous structures. Using the existing theoretical approaches to modeling self-organized structures in dust plasmas, the parameter distribution of a structure is recalculated for a simpler model that includes the quasineutrality condition and neglects diffusion. These calculations indicate that under microgravity conditions, any self-organized structure can contain a limited number of dust particles and is finite in size. The maximum possible number of particles in a structure determines the characteristic inter-grain distance in dust crystals that can be created under microgravity conditions. Crystallization criteria for the structures are examined and the quasispherical

  15. Organic chemistry of cometary dust as derived from PUMA 1 data

    Science.gov (United States)

    Kissel, J.; Krueger, F. R.

    1989-01-01

    Onboard the Halley Fly-By spacecrafts Vega 1, Vega 2, and Giotto were the dust impact mass spectrometers PUMA 1, PUMA 2, and PIA respectively. PUMA 1 was the most sensitive instrument among them. From its data the occurrence of masslines greater than 60 Daltons could be shown to be statistically significant. An analysis of these masslines lead to a scenario, which could explain the masslines as fragment ions from larger molecules which characterize the chemical nature of cometary organic matter as: (1) highly unsaturated hydrocarbons; (2) some of them containing oxygen; (3) less containing nitrogen; and (4) a few containing oxygen and nitrogen as heteroatoms. From the properties of the spectrometer, also some physical parameters of the dust particles could be inferred, such as their density and structure.

  16. Effect of malachite green toxicity on non target soil organisms.

    Science.gov (United States)

    Gopinathan, R; Kanhere, J; Banerjee, J

    2015-02-01

    Although malachite green (MG), is banned in Europe and US for its carcinogenic and teratogenic effect, the dye being cheap, is persistently used in various countries for fish farming, silk, dye, leather and textile industries. Current research, however, fails to elucidate adequate knowledge concerning the effects of MG in our ecosystem. In the present investigation, for the first time, an attempt has been made to study the effects of MG on soil biota by testing Bacillus subtilis, Azotobacter chroococcum, Saccharomyces cerevisiae, Penicillium roqueforti, Eisenia fetida and seeds of three crop plants of different families. Various tests were conducted for determining cytotoxicity, genotoxicity, acute toxicity, morphological and germination effect. Our data confirmed MG toxicity on fungi and bacteria (gram positive and gram negative organisms) showing elevated level of ROS. Genotoxicity caused in the microorganisms was detected by DNA polymorphism and fragmentation. Also, scanning electron microscopy data suggests that the inhibitory effect of MG to these beneficial microbes in the ecosystem might be due to pore formation in the cell and its eventual disruption. Filter paper and artificial soil test conducted on earthworms demonstrated a LC 50 of 2.6 mg cm(-2) and 1.45 mg kg(-1) respectively with severe morphological damage. However, seed germination of Mung bean, Wheat and Mustard was found to be unaffected in presence of MG up to 100 mL(-1) concentration. Thus, understanding MG toxicity in non target soil organisms and emphasis on its toxicological effects would potentially explicate its role as an environmental contaminant. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Alteration of Organic Compounds in Small Bodies and Cosmic Dusts by Cosmic Rays and Solar Radiation

    Science.gov (United States)

    Kobayashi, Kensei; Kaneko, Takeo; Mita, Hajime; Obayashi, Yumiko; Takahashi, Jun-ichi; Sarker, Palash K.; Kawamoto, Yukinori; Okabe, Takuto; Eto, Midori; Kanda, Kazuhiro

    2012-07-01

    A wide variety of complex organic compounds have been detected in extraterrestrial bodies like carbonaceous chondrites and comets, and their roles in the generation of terrestrial life are discussed. It was suggested that organics in small bodies were originally formed in ice mantles of interstellar dusts in dense cloud. Irradiation of frozen mixture of possible interstellar molecules including CO (or CH _{3}OH), NH _{3} and H _{2}O with high-energy particles gave complex amino acid precursors with high molecular weights [1]. Such complex organic molecules were taken in planetesimals or comets in the early solar system. In prior to the generation of the terrestrial life, extraterrestrial organics were delivered to the primitive Earth by such small bodies as meteorites, comets and space dusts. These organics would have been altered by cosmic rays and solar radiation (UV, X-rays) before the delivery to the Earth. We examined possible alteration of amino acids, their precursors and nucleic acid bases in interplanetary space by irradiation with high energy photons and heavy ions. A mixture of CO, NH _{3} and H _{2}O was irradiated with high-energy protons from a van de Graaff accelerator (TIT, Japan). The resulting products (hereafter referred to as CAW) are complex precursors of amino acids. CAW, amino acids (dl-Isovaline, glycine), hydantoins (amino acid precursors) and nucleic acid bases were irradiated with continuous emission (soft X-rays to IR; hereafter referred to as soft X-rays irradiation) from BL-6 of NewSUBARU synchrotron radiation facility (Univ. Hyogo). They were also irradiated with heavy ions (eg., 290 MeV/u C ^{6+}) from HIMAC accelerator (NIRS, Japan). After soft X-rays irradiation, water insoluble materials were formed. After irradiation with soft X-rays or heavy ions, amino acid precursors (CAW and hydantoins) gave higher ratio of amino acids were recovered after hydrolysis than free amino acids. Nucleic acid bases showed higher stability than free

  18. Saharan dust - a carrier of persistent organic pollutants, metals and microbes to the Caribbean?

    Directory of Open Access Journals (Sweden)

    V.H Garrison

    2006-12-01

    Full Text Available An international team of scientists from government agencies and universities in the United States, U.S. Virgin Islands (USVI, Trinidad & Tobago, the Republic of Cape Verde, and the Republic of Mali (West Africa is working together to elucidate the role Saharan dust may play in the degradation of Caribbean ecosystems. The first step has been to identify and quantify the persistent organic pollutants (POPs, trace metals, and viable microorganisms in the atmosphere in dust source areas of West Africa, and in dust episodes at downwind sites in the eastern Atlantic (Cape Verde and the Caribbean (USVI and Trinidad & Tobago. Preliminary findings show that air samples from Mali contain a greater number of pesticides, polychlorinated biphenyls (PCBs and polycyclic aromatic hydrocarbons (PAHs and in higher concentrations than the Caribbean sites. Overall, POP concentrations were similar in USVI and Trinidad samples. Trace metal concentrations were found to be similar to crustal composition with slight enrichment of lead in Mali. To date, hundreds of cultureable micro-organisms have been identified from Mali, Cape Verde, USVI, and Trinidad air samples. The sea fan pathogen, Aspergillus sydowii, has been identified in soil from Mali and in air samples from dust events in the Caribbean. We have shown that air samples from a dust-source region contain orders of magnitude more cultureable micro-organisms per volume than air samples from dust events in the Caribbean, which in turn contain 3-to 4-fold more cultureable microbes than during non-dust conditions. Rev. Biol. Trop. 54 (Suppl. 3: 9-21. Epub 2007 Jan. 15.Un grupo internacional de agencias gubernamentales y universidades de los Estados Unidos, las Islas Vírgenes (EUA, Trinidad y Tobago, la República de Cabo Verde y la República de Mali (África Oeste, está trabajando en conjunto para elucidar el papel que el polvo del Sahara puede estar jugando en el deterioro de los ecosistemas caribeños. El

  19. Fluid-induced organic synthesis in the solar nebula recorded in extraterrestrial dust from meteorites.

    Science.gov (United States)

    Vollmer, Christian; Kepaptsoglou, Demie; Leitner, Jan; Busemann, Henner; Spring, Nicole H; Ramasse, Quentin M; Hoppe, Peter; Nittler, Larry R

    2014-10-28

    Isotopically anomalous carbonaceous grains in extraterrestrial samples represent the most pristine organics that were delivered to the early Earth. Here we report on gentle aberration-corrected scanning transmission electron microscopy investigations of eight (15)N-rich or D-rich organic grains within two carbonaceous Renazzo-type (CR) chondrites and two interplanetary dust particles (IDPs) originating from comets. Organic matter in the IDP samples is less aromatic than that in the CR chondrites, and its functional group chemistry is mainly characterized by C-O bonding and aliphatic C. Organic grains in CR chondrites are associated with carbonates and elemental Ca, which originate either from aqueous fluids or possibly an indigenous organic source. One distinct grain from the CR chondrite NWA 852 exhibits a rim structure only visible in chemical maps. The outer part is nanoglobular in shape, highly aromatic, and enriched in anomalous nitrogen. Functional group chemistry of the inner part is similar to spectra from IDP organic grains and less aromatic with nitrogen below the detection limit. The boundary between these two areas is very sharp. The direct association of both IDP-like organic matter with dominant C-O bonding environments and nanoglobular organics with dominant aromatic and C-N functionality within one unique grain provides for the first time to our knowledge strong evidence for organic synthesis in the early solar system activated by an anomalous nitrogen-containing parent body fluid.

  20. Evolution of organic and inorganic components of aerosol during a Saharan dust episode observed in the French Alps

    Directory of Open Access Journals (Sweden)

    G. Aymoz

    2004-01-01

    Full Text Available A Saharan dust event was observed in a rural area in the Maurienne Valley (French Alps in summer 2000. Detailed data on PM10, particle numbers, and aerosol chemistry (ionic species and Elemental Carbon (EC and Organic Carbon (OC are presented. The comparative evolutions of particle numbers and chemistry (calcium, sodium, and sulfate show that the overall period included two episodes of dust particles with very distinct chemistry, followed by an episode with a large increase of the concentrations of species with an anthropogenic origin. The overall data set does not indicate large interactions between the dust particles and compounds from anthropogenic origin (sulfate, nitrate or with organic carbon, all of these species showing very low concentrations. Simplistic calculations indicate that these concentrations are consistent with our current knowledge of adsorption processes of gases on mineral dust in a clean air mass.

  1. Organization and effectivity of works on dust suppressing in the special zone of the Chernobyl' NPP

    International Nuclear Information System (INIS)

    Shimin, S.A.; Krapchatov, V.P.; Nad''yarnykh, G.V.; Komarov, V.I.; Andreev, Yu.B.; Samojlenko, Yu.N.

    1989-01-01

    In 1988 three methods of dust suppressing were used: regular watering of roads, chemical treatment of roadsides and dusting sections of area, long-time biologochemical fixation of open sections of area, including sowing with grass and simultaneous treatment by dust-suppressing compositions. Preliminary treatment of objects by polymeric compositions was an effective action to reduce dust-raising. 3 refs.; 3 figs

  2. Comparison of a direct-reading device to gravimetric methods for evaluating organic dust aerosols in an enclosed swine production environment.

    Science.gov (United States)

    Taylor, C D; Reynolds, S J

    2001-01-01

    The production of livestock in enclosed facilities has become an accepted practice, driven by the need for increased efficiency. Exposure to organic dusts, containing various bioactive components, has been identified an important risk factor for the high rate of lung disease found among workers in these environments. Assessment of organic dust exposure requires technical skills and instrumentation not readily available to most agricultural enterprises. Development of a simple, cost-effective method for measuring organic dust levels would be useful in evaluating and controlling exposures in these environments. The objective of this study was to evaluate the usefulness of the direct reading MIE PDM-3 Miniram for estimating organic dust concentrations in enclosed swine production facilities. Responses from the MIE PDM-3 Miniram were compared to gravimetric methods for total and inhalable dust. Total dust determinations were conducted in accordance with the National Institute for Occupational Safety and Health (NIOSH) method 0500. Inhalable particulate mass (IPM) sampling was conducted using SKC brand IOM (Institute of Occupational Medicine) sampling cassettes, which meet the American Conference of Governmental Industrial Hygienists ACGIH criteria for inhalable dust sampling. This study design also allowed for the comparison of traditional total dust method to the IPM method, in collecting organic dusts in an agricultural setting. Fifteen sets of side-by-side samples (Miniram, total dust, and IPM) were collected over a period of six months in a swine confinement building. There were statistically significant differences in the results provided by the three sampling methods. Measurements for inhalable dust exceeded those for total dust in eleven of fifteen samples. The Miniram time-weighted average (TWA) response to the organic dust was always the lower of the three methods. A high degree of correlation was found among all three methods. The Miniram performed well under

  3. Impact of dust filter installation in ironworks and construction on brownfield area on the toxic metal concentration in street and house dust (Celje, Slovenia).

    Science.gov (United States)

    Zibret, Gorazd

    2012-05-01

    This article presents the impact of the ecological investment in ironworks (dust filter installation) and construction works at a highly contaminated brownfield site on the chemical composition of household dust (HD) and street sediment (SS) in Celje, Slovenia. The evaluation is based on two sampling campaigns: the first was undertaken 1 month before the ecological investment became operational and the second 3 years later. The results show that dust filter installations reduced the content of Co, Cr, Fe, Mn, Mo, W and Zn on average by 58% in HD and by 51% in SS. No reduction was observed at sampling points in the upwind direction from the ironworks. By contrast, the impact of the construction works on the highly contaminated brownfield site was detected by a significant increase (on average by 37%) of elements connected to the brownfield contamination in SS. Such increase was not detected in HD.

  4. Pesticide Toxicity Index: a tool for assessing potential toxicity of pesticide mixtures to freshwater aquatic organisms

    Science.gov (United States)

    Nowell, Lisa H.; Norman, Julia E.; Moran, Patrick W.; Martin, Jeffrey D.; Stone, Wesley W.

    2014-01-01

    Pesticide mixtures are common in streams with agricultural or urban influence in the watershed. The Pesticide Toxicity Index (PTI) is a screening tool to assess potential aquatic toxicity of complex pesticide mixtures by combining measures of pesticide exposure and acute toxicity in an additive toxic-unit model. The PTI is determined separately for fish, cladocerans, and benthic invertebrates. This study expands the number of pesticides and degradates included in previous editions of the PTI from 124 to 492 pesticides and degradates, and includes two types of PTI for use in different applications, depending on study objectives. The Median-PTI was calculated from median toxicity values for individual pesticides, so is robust to outliers and is appropriate for comparing relative potential toxicity among samples, sites, or pesticides. The Sensitive-PTI uses the 5th percentile of available toxicity values, so is a more sensitive screening-level indicator of potential toxicity. PTI predictions of toxicity in environmental samples were tested using data aggregated from published field studies that measured pesticide concentrations and toxicity to Ceriodaphnia dubia in ambient stream water. C. dubia survival was reduced to ≤ 50% of controls in 44% of samples with Median-PTI values of 0.1–1, and to 0% in 96% of samples with Median-PTI values > 1. The PTI is a relative, but quantitative, indicator of potential toxicity that can be used to evaluate relationships between pesticide exposure and biological condition.

  5. Transformation of Graphitic and Amorphous Carbon Dust to Complex Organic Molecules in a Massive Carbon Cycle in Protostellar Nebulae

    Science.gov (United States)

    Nuth, Joseph A., III; Johnson, Natasha M.

    2012-01-01

    More than 95% of silicate minerals and other oxides found in meteorites were melted, or vaporized and recondensed in the Solar Nebula prior to their incorporation into meteorite parent bodies. Gravitational accretion energy and heating via radioactive decay further transformed oxide minerals accreted into planetesimals. In such an oxygen-rich environment the carbonaceous dust that fell into the nebula as an intimate mixture with oxide grains should have been almost completely converted to CO. While some pre-collapse, molecular-cloud carbonaceous dust does survive, much in the same manner as do pre-solar oxide grains, such materials constitute only a few percent of meteoritic carbon and are clearly distinguished by elevated D/H, N-15/N-16, C-13/C-12 ratios or noble gas patterns. Carbonaceous Dust in Meteorites: We argue that nearly all of the carbon in meteorites was synthesized in the Solar Nebula from CO and that this CO was generated by the reaction of carbonaceous dust with solid oxides, water or OH. It is probable that some fraction of carbonaceous dust that is newly synthesized in the Solar Nebula is also converted back into CO by additional thermal processing. CO processing might occur on grains in the outer nebula through irradiation of CO-containing ice coatings or in the inner nebula via Fischer-Tropsch type (FTT) reactions on grain surfaces. Large-scale transport of both gaseous reaction products and dust from the inner nebula out to regions where comets formed would spread newly formed carbonaceous materials throughout the solar nebula. Formation of Organic Carbon: Carbon dust in the ISM might easily be described as inorganic graphite or amorphous carbon, with relatively low structural abundances of H, N, O and S . Products of FTT reactions or organics produced via irradiation of icy grains contain abundant aromatic and aliphatic hydrocarbons. aldehydes, keytones, acids, amines and amides.. The net result of the massive nebular carbon cycle is to convert

  6. Effect of Organic Dust Exposure on Pulmonary Functions in Workers of Vegetable Market with Special Reference to its Microbial Content.

    Science.gov (United States)

    Goel, Arun; Omar, Balram Ji; Kathrotia, Rajesh; Patil, Prashant M; Mittal, Sunita

    2018-01-01

    Wholesale vegetable market is a rich source of generation of organic dust as loads of fruits and vegetables are loaded and unloaded here daily. Thus, regular workers are exposed to this organic dust for a considerable period of time depending on their work schedule. This study was planned to determine the microbial status of organic dust and to explore its association with pulmonary functions in the workers of wholesale vegetable market in Rishikesh. It was a cross-sectional exploratory/observational study. Thirty-five apparently healthy adult males were selected from vegetable market having no history of any chronic illness. Smokers and alcoholic were excluded from the study. The same number of age- and sex-matched controls with the same exclusion criteria were recruited from workers not working in the vegetable market and also not exposed to any other kinds of organic dust. Microbial culture of air in the vegetable market was done. It was compared with the microbial status of air in the working place of controls. Pulmonary functions of all the workers were performed with the help of digital spirometer (Helios 401). Bacterial and fungal concentration was found to be significantly higher in the air of vegetable market as compared to air in the workplace of controls (such as coagulase-negative staphylococci >25 colony-forming unit (CFU) at incubation temperature vs. 10-12 CFU at incubation temperature, significant growth of Mucor , Aspergillus niger , and Candida nonalbicans in vegetable market as compared to workplace of controls). Pulmonary function parameters (percentage forced expiratory volume in 1 st s (FEV 1 ), percentage predicted forced expiratory flow in mid-half of expiration, and FEV 1 ) of workers exposed to organic dust in vegetable market were also significantly lower ( P < 0.05). Exposure of organic dust is associated with compromised pulmonary functions and there is a need of formulation of safety guidelines.

  7. Nitrogen isotopic composition of macromolecular organic matter in interplanetary dust particles

    Science.gov (United States)

    Aléon, Jérôme; Robert, François; Chaussidon, Marc; Marty, Bernard

    2003-10-01

    Nitrogen concentrations and isotopic compositions were measured by ion microprobe scanning imaging in two interplanetary dust particles L2021 K1 and L2036 E22, in which imaging of D/H and C/H ratios has previously evidenced the presence of D-rich macromolecular organic components. High nitrogen concentrations of 10-20 wt% and δ 15N values up to +400‰ are observed in these D-rich macromolecular components. The previous study of D/H and C/H ratios has revealed three different D-rich macromolecular phases. The one previously ascribed to macromolecular organic matter akin the insoluble organic matter (IOM) from carbonaceous chondrites is enriched in nitrogen by one order of magnitude compared to the carbonaceous chondrite IOM, although its isotopic composition is still similar to what is known from Renazzo (δ 15N = +208‰). The correlation observed in macromolecular organic material between the D- and 15N-excesses suggests that the latter originate probably from chemical reactions typical of the cold interstellar medium. These interstellar materials preserved to some extent in IDPs are therefore macromolecular organic components with various aliphaticity and aromaticity. They are heavily N-heterosubstituted as shown by their high nitrogen concentrations >10 wt%. They have high D/H ratios >10 -3 and δ 15N values ≥ +400‰. In L2021 K1 a mixture is observed at the micron scale between interstellar and chondritic-like organic phases. This indicates that some IDPs contain organic materials processed at various heliocentric distances in a turbulent nebula. Comparison with observation in comets suggests that these molecules may be cometary macromolecules. A correlation is observed between the D/H ratios and δ 15N values of macromolecular organic matter from IDPs, meteorites, the Earth and of major nebular reservoirs. This suggests that most macromolecular organic matter in the inner solar system was probably issued from interstellar precursors and further processed

  8. Acute toxicity of anionic and non-ionic surfactants to aquatic organisms.

    Science.gov (United States)

    Lechuga, M; Fernández-Serrano, M; Jurado, E; Núñez-Olea, J; Ríos, F

    2016-03-01

    The environmental risk of surfactants requires toxicity measurements. As different test organisms have different sensitivity to the toxics, it is necessary to establish the most appropriate organism to classify the surfactant as very toxic, toxic, harmful or safe, in order to establish the maximum permissible concentrations in aquatic ecosystems. We have determined the toxicity values of various anionic surfactants ether carboxylic derivatives using four test organisms: the freshwater crustacean Daphnia magna, the luminescent bacterium Vibrio fischeri, the microalgae Selenastrum capricornutum (freshwater algae) and Phaeodactylum tricornutum (seawater algae). In addition, in order to compare and classify the different families of surfactants, we have included a compilation of toxicity data of surfactants collected from literature. The results indicated that V. fischeri was more sensitive to the toxic effects of the surfactants than was D. magna or the microalgae, which was the least sensitive. This result shows that the most suitable toxicity assay for surfactants may be the one using V. fischeri. The toxicity data revealed considerable variation in toxicity responses with the structure of the surfactants regardless of the species tested. The toxicity data have been related to the structure of the surfactants, giving a mathematical relationship that helps to predict the toxic potential of a surfactant from its structure. Model-predicted toxicity agreed well with toxicity values reported in the literature for several surfactants previously studied. Predictive models of toxicity is a handy tool for providing a risk assessment that can be useful to establish the toxicity range for each surfactant and the different test organisms in order to select efficient surfactants with a lower impact on the aquatic environment. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Exposure to Inhalable Dust, Endotoxin, and Total Volatile Organic Carbons on Dairy Farms Using Manual and Automated Feeding Systems

    DEFF Research Database (Denmark)

    Basinas, Ioannis; Cronin, Garvin; Hogan, Victoria

    2017-01-01

    Introduction: Agricultural workers tend to have high exposures to organic dusts which may induce or exacerbate respiratory disorders. Studies investigating the effect of work tasks and farm characteristics on organic dust exposures among farm workers suggest that handling of animal feed is an imp...... feeding. Until effective permanent engineering controls are established farm workers should be encouraged to wear respiratory protective equipment during these tasks....... of exposure to these agents depend on the applied feeding system in the farms. Methods: Thirty-eight personal exposure measurements were collected from farmers across seven dairy farms. The farms used manual, loft, or semi-automated feeding systems. Information on worker tasks and farm characteristics...

  10. Evaluation of the toxicity of organic matter in marine sediments

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.

    stream_size 3 stream_content_type text/plain stream_name 2_Int_Conf_Waste_Mgmt_Chem_Petrochem_Ind_Toxic_Mgmt_1991_258.pdf.txt stream_source_info 2_Int_Conf_Waste_Mgmt_Chem_Petrochem_Ind_Toxic_Mgmt_1991_258.pdf.txt Content...

  11. Toxicity of petroleum hydrocarbon distillates to soil organisms.

    Science.gov (United States)

    Cermak, Janet H; Stephenson, Gladys L; Birkholz, Detlef; Wang, Zhendi; Dixon, D George

    2010-12-01

    Canadian standards for petroleum hydrocarbons in soil are based on four distillate ranges (F1, C6-C10; F2, >C10-C16; F3, >C16-C34; and F4, >C34). Concerns have arisen that the ecological soil contact standards for F3 may be overly conservative. Oil distillates were prepared and characterized, and the toxicity of F3 and two subfractions, F3a (>C16-C23) and F3b (>C23-C34), to earthworms (Eisenia andrei), springtails (Orthonychiurus folsomi), and northern wheatgrass (Elymus lanceolatus), as well as the toxicity of F2 to earthworms, was determined. Clean soil was spiked with individual distillates and measured concentrations were determined for select tests. Results agree with previous studies with these distillates. Reported toxicities of crude and petroleum products to invertebrates were generally comparable to that of F3 and F3a. The decreasing order of toxicity was F3a > F3 > F3b with invertebrates, and F3a > F3b > F3 with plants. The toxicities of F3a and F3b were not sufficiently different to recommend regulating hydrocarbons based on these distillate ranges. The results also suggest that test durations may be insufficient for determining toxicity of higher distillate ranges, and that the selection of species and endpoints may significantly affect interpretation of toxicity test results. Copyright © 2010 SETAC.

  12. House dust in seven Danish offices

    Science.gov (United States)

    Mølhave, L.; Schneider, T.; Kjærgaard, S. K.; Larsen, L.; Norn, S.; Jørgensen, O.

    Floor dust from Danish offices was collected and analyzed. The dust was to be used in an exposure experiment. The dust was analyzed to show the composition of the dust which can be a source of airborne dust indoors. About 11 kg of dust from vacuum cleaner bags from seven Danish office buildings with about 1047 occupants (12 751 m 2) was processed according to a standardized procedure yielding 5.5 kg of processed bulk dust. The bulk dust contained 130.000-160.000 CFU g -1 microorganisms and 71.000-90.000 CFU g -1 microfungi. The content of culturable microfungi was 65-123 CFU 30 g -1 dust. The content of endotoxins ranged from 5.06-7.24 EU g -1 (1.45 ng g -1 to 1.01 ng g -1). Allergens (ng g -1) were from 147-159 (Mite), 395-746 (dog) and 103-330 (cat). The macro molecular organic compounds (the MOD-content) varied from 7.8-9.8 mg g -1. The threshold of release of histamine from basophil leukocytes provoked by the bulk dust was between 0.3 and 1.0 mg ml -1. The water content was 2% (WGT) and the organic fraction 33%. 6.5-5.9% (dry) was water soluble. The fiber content was less than 0.2-1.5% (WGT) and the desorbable VOCs was 176-319 μg g -1. Most of the VOC were aldehydes. However, softeners for plastic (DBP and DEHP) were present. The chemical composition includes human and animal skin fragments, paper fibers, glass wool, wood and textilefibers and inorganic and metal particles. The sizes ranged from 0.001-1 mm and the average specific density was 1.0 g m -3. The bulk dust was resuspended and injected into an exposure chamber. The airborne dust was sampled and analyzed to illustrate the exposures that can result from sedimented dirt and dust. The airborne dust resulting from the bulk dust reached concentrations ranging from 0.26-0.75 mg m -3 in average contained 300-170 CFU m -3. The organic fraction was from 55-70% and the water content about 2.5% (WGT). The content of the dust was compared to the similar results reported in the literature and its toxic potency is

  13. Comparative toxicity of sodium carbonate peroxyhydrate to freshwater organisms.

    Science.gov (United States)

    Geer, Tyler D; Kinley, Ciera M; Iwinski, Kyla J; Calomeni, Alyssa J; Rodgers, John H

    2016-10-01

    Sodium carbonate peroxyhydrate (SCP) is a granular algaecide containing H2O2 as an active ingredient to control growth of noxious algae. Measurements of sensitivities of target and non-target species to hydrogen peroxide are necessary for water resource managers to make informed decisions and minimize risks for non-target species when treating noxious algae. The objective of this study was to measure and compare responses among a target noxious alga (cyanobacterium Microcystis aeruginosa) and non-target organisms including a eukaryotic alga (chlorophyte Pseudokirchneriella subcapitata), microcrustacean (Ceriodaphnia dubia), benthic amphipod (Hyalella azteca), and fathead minnow (Pimephales promelas) to exposures of hydrogen peroxide as SCP. Hydrogen peroxide exposures were confirmed using the I3(-) method. SCP margins of safety for these organisms were compared with published toxicity data to provide context for other commonly used algaecides and herbicides (e.g. copper formulations, endothall, and diquat dibromide). Algal responses (cell density and chlorophyll a concentrations) and animal mortality were measured after 96h aqueous exposures to SCP in laboratory-formulated water to estimate EC50 and LC50 values, as well as potency slopes. Despite a shorter test duration, M. aeruginosa was more sensitive to hydrogen peroxide as SCP (96h EC50:0.9-1.0mgL(-)(1) H2O2) than the eukaryotic alga P. subcapitata (7-d EC50:5.2-9.2mgL(-1) H2O2), indicating potential for selective control of prokaryotic algae. For the three non-target animals evaluated, measured 96-h LC50 values ranged from 1.0 to 19.7mgL(-1) H2O2. C. dubia was the most sensitive species, and the least sensitive species was P. promelas, which is not likely to be affected by concentrations of hydrogen peroxide as SCP that would be used to control noxious algae (e.g. M. aeruginosa). Based on information from peer-reviewed literature, other algaecides could be similarly selective for cyanobacteria. Of the

  14. Overview of major hazards. Part 2: Source term; dispersion; combustion; blast, missiles, venting; fire; radiation; runaway reactions; toxic substances; dust explosions

    Science.gov (United States)

    Vilain, J.

    Approaches to major hazard assessment and prediction are reviewed. Source term: (phenomenology/modeling of release, influence on early stages of dispersion); dispersion (atmospheric advection, diffusion and deposition, emphasis on dense/cold gases); combustion (flammable clouds and mists covering flash fires, deflagration, transition to detonation; mostly unconfined/partly confined situations); blast formation, propagation, interaction with structures; catastrophic fires (pool fires, torches and fireballs; highly reactive substances) runaway reactions; features of more general interest; toxic substances, excluding toxicology; and dust explosions (phenomenology and protective measures) are discussed.

  15. Grain dust originating from organic and conventional farming as a potential source of biological agents causing respiratory diseases in farmers.

    Science.gov (United States)

    Zukiewicz-Sobczak, Wioletta A; Cholewa, Grażyna; Krasowska, Ewelina; Chmielewska-Badora, Jolanta; Zwoliński, Jacek; Sobczak, Paweł

    2013-12-01

    Agricultural producers are exposed to a number of different health risks associated with their work environment. The objective of the study was to assess the degree of colonization by fungi in terms of quantity and in terms of variety of species the samples taken from the settled dust from combine threshing of rye cultivation from organic and conventional farms in the Province of Lublin. This paper is a preliminary quantitative assessment of the species of fungi colonizing the samples of settled dust collected during combine threshing from organic and conventional farms in the Province of Lublin. One of the stages of the project was the classification of biosafety BSL (biosafety level) of selected isolates and API ZYM tests to evaluate the potential ability of isolates to cause adverse health effects. To determine the concentration and composition of fungi in collected samples plate dilution method was used with two media: Malt Agar and Potato Dextrose Agar. MOST COMMONLY ISOLATED FUNGI IN SETTLED DUST SAMPLES COLLECTED DURING COMBINE THRESHING FROM ORGANIC FARMS, ON PDA MEDIUM WERE: Alternaria alternata and Aureobasidium pullulans. Cultures on MA medium were dominated by Alternaria alternata, Mycelia sterilia and Fusarium poae. In samples of dust from conventional crops, the predominant species was Alternaria alternata on PDA medium and on MA medium. The obtained results show a potential risk of people involved in agricultural work.

  16. Typical halogenated persistent organic pollutants in indoor dust and the associations with childhood asthma in Shanghai, China.

    Science.gov (United States)

    Meng, Ge; Nie, Zhiqing; Feng, Yan; Wu, Xiaomeng; Yin, Yong; Wang, Yan

    2016-04-01

    Halogenated persistent organic pollutants (Hal-POPs) are significant contaminants in the indoor environment that are related to many human diseases. Ingestion of indoor dust is considered the major pathway of Hal-POP exposures, especially for children aged 3-6 years. Alongside a retrospective study on the associations between typical Hal-POP exposure and childhood asthma in Shanghai, indoor dust samples from asthmatic and non-asthmatic children's homes (n = 60, each) were collected. Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were measured by GC-MS. BDE-209, PCB-8 and p,p'-DDE were the predominant components in each chemical category. The concentrations of most Hal-POPs were significantly higher in the asthmatic families. The associations between Hal-POP exposure and asthma occurrence were examined by calculating the odds ratios (ORs) using a logistic regression model. A positive association was found between p,p'-DDE in indoor dust and childhood asthma (OR = 1.825, 95%CI: 1.004, 3.317; p = 0.048). The average daily doses of Hal-POP intake were calculated using the method provided by the USEPA. Non-carcinogenic health risks were preliminarily assessed. Our study indicated that exposure to p,p'-DDE via indoor dust may contribute to childhood asthma occurrence. Non-carcinogenic health risks were not found with the intake of Hal-POPs via the ingestion of indoor dust. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. DC Glow Discharge Plasma, Containing Dust Particles: Self Organization and Peculiarities of Behavior

    International Nuclear Information System (INIS)

    Molotkov, V.I.; Pustyl'nik, M.Y.; Torchinskij, V.M.; Fortov, V.E.

    2003-01-01

    Dust particles, immersed in a plasma, acquire charge due to which they may be electrostatically trapped in a plasma. The energy of the interaction of the dust particles may be enough to transfer the dust component to nonideal and even crystalline state. This phenomenon is observed in various plasmas. In the present work a review of the investigations of strongly nonideal dusty plasma of the dc glow discharge striations is given. The formation of plasma crystals, liquids and plasma liquid crystals is considered. Typical phenomenon a for the dc discharge dusty plasma, such as coexistence of different phases in a single structure, convective motions, dust acoustic instability, are underlined. Results of the experiments on different external influences on dusty plasma structures are stated. It is shown that external influences may be used for measuring of the particle charge and field of forces acting on a dust grain levitating in a plasma. (author)

  18. Structural, chemical and isotopic examinations of interstellar organic matter extracted from meteorites and interstellar dust particles

    Science.gov (United States)

    Busemann, Henner; Alexander, Conel M. O'D.; Nittler, Larry R.; Stroud, Rhonda M.; Zega, Tom J.; Cody, George D.; Yabuta, Hikaru; Kilcoyne, A. L. David

    2008-10-01

    Meteorites and Interplanetary Dust Particles (IDPs) are supposed to originate from asteroids and comets, sampling the most primitive bodies in the Solar System. They contain abundant carbonaceous material. Some of this, mostly insoluble organic matter (IOM), likely originated in the protosolar molecular cloud, based on spectral properties and H and N isotope characteristics. Together with cometary material returned with the Stardust mission, these samples provide a benchmark for models aiming to understand organic chemistry in the interstellar medium, as well as for mechanisms that secured the survival of these fragile molecules during Solar System formation. The carrier molecules of the isotope anomalies are largely unknown, although amorphous carbonaceous spheres, so-called nanoglobules, have been identified as carriers. We are using Secondary Ion Mass Spectrometry to identify isotopically anomalous material in meteoritic IOM and IDPs at a ~100-200 nm scale. Organics of most likely interstellar origin are then extracted with the Focused-Ion-Beam technique and prepared for synchrotron X-ray and Transmission Electron Microscopy. These experiments yield information on the character of the H- and N-bearing interstellar molecules: While the association of H and N isotope anomalies with nanoglobules could be confirmed, we have also identified amorphous, micron-sized monolithic grains. D-enrichments in meteoritic IOM appear not to be systematically associated with any specific functional groups, whereas 15N-rich material can be related to imine and nitrile functionality. The large 15N- enrichments observed here (δ15N > 1000 ‰) cannot be reconciled with models using interstellar ammonia ice reactions, and hence, provide new constraints for understanding the chemistry in cold interstellar clouds.

  19. Use of Monte Carlo analysis in a risk-based prioritization of toxic constituents in house dust.

    Science.gov (United States)

    Ginsberg, Gary L; Belleggia, Giuliana

    2017-12-01

    Many chemicals have been detected in house dust with exposures to the general public and particularly young children of potential health concern. House dust is also an indicator of chemicals present in consumer products and the built environment that may constitute a health risk. The current analysis compiles a database of recent house dust concentrations from the United States and Canada, focusing upon semi-volatile constituents. Seven constituents from the phthalate and flame retardant categories were selected for risk-based screening and prioritization: diethylhexyl phthalate (DEHP), butyl benzyl phthalate (BBzP), diisononyl phthalate (DINP), a pentabrominated diphenyl ether congener (BDE-99), hexabromocyclododecane (HBCDD), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and tris(2-chloroethyl) phosphate (TCEP). Monte Carlo analysis was used to represent the variability in house dust concentration as well as the uncertainty in the toxicology database in the estimation of children's exposure and risk. Constituents were prioritized based upon the percentage of the distribution of risk results for cancer and non-cancer endpoints that exceeded a hazard quotient (HQ) of 1. The greatest percent HQ exceedances were for DEHP (cancer and non-cancer), BDE-99 (non-cancer) and TDCIPP (cancer). Current uses and the potential for reducing levels of these constituents in house dust are discussed. Exposure and risk for other phthalates and flame retardants in house dust may increase if they are used to substitute for these prioritized constituents. Therefore, alternative assessment and green chemistry solutions are important elements in decreasing children's exposure to chemicals of concern in the indoor environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. The Simplest Flowchart Stating the Mechanisms for Organic Xenobiotics-induced Toxicity: Can it Possibly be Accepted as a "Central Dogma" for Toxic Mechanisms?

    Science.gov (United States)

    Park, Yeong-Chul; Lee, Sundong; Cho, Myung-Haing

    2014-09-01

    Xenobiotics causing a variety of toxicity in biological systems could be classified as two types, inorganic and organic chemicals. It is estimated that the organic xenobiotics are responsible for approximately 80~90% of chemical-induced toxicity in human population. In the class for toxicology, we have encountered some difficulties in explaining the mechanisms of toxicity caused especially by organic chemicals. Here, a simple flowchart was introduced for explaining the mechanism of toxicity caused by organic xenobiotics, as the central dogma of molecular biology. This flowchart, referred to as a central dogma, was described based on a view of various aspects as follows: direct-acting chemicals vs. indirect-acting chemicals, cytochrome P450-dependent vs. cytochrome P450-independent biotransformation, reactive intermediates, reactivation, toxicokinetics vs. toxicodynamics, and reversibility vs. irreversibility. Thus, the primary objective of this flowchart is to help better understanding of the organic xenobiotics-induced toxic mechanisms, providing a major pathway for toxicity occurring in biological systems.

  1. Plant-associated bacterial degradation of toxic organic compounds in soil.

    LENUS (Irish Health Repository)

    McGuinness, Martina

    2009-08-01

    A number of toxic synthetic organic compounds can contaminate environmental soil through either local (e.g., industrial) or diffuse (e.g., agricultural) contamination. Increased levels of these toxic organic compounds in the environment have been associated with human health risks including cancer. Plant-associated bacteria, such as endophytic bacteria (non-pathogenic bacteria that occur naturally in plants) and rhizospheric bacteria (bacteria that live on and near the roots of plants), have been shown to contribute to biodegradation of toxic organic compounds in contaminated soil and could have potential for improving phytoremediation. Endophytic and rhizospheric bacterial degradation of toxic organic compounds (either naturally occurring or genetically enhanced) in contaminated soil in the environment could have positive implications for human health worldwide and is the subject of this review.

  2. Evaluation of the treatment efficiencies of paper mill whitewaters in terms of organic composition and toxicity

    International Nuclear Information System (INIS)

    Latorre, Anna; Malmqvist, Asa; Lacorte, Silvia; Welander, Thomas; Barcelo, Damia

    2007-01-01

    The efficiency of several lab scale treatments (aerobic, anaerobic and ozone or combination of these) was evaluated using two packaging board mill whitewaters. The effect of the different treatments on the elimination of the organic load, the chemical oxygen demand (COD) and the toxicity was tested as well as the relationship between these parameters. Biocides, phenolic compounds, surfactants, plasticiziers and wood extractives were identified in untreated and treated whitewaters by liquid chromatography coupled with mass spectrometry (LC-MS) or gas chromatography coupled with mass spectrometry (GC-MS). A strong dependency on the water type and treatment efficiency was observed, being the combination of anaerobic and aerobic treatments the best option to reduce the organic contaminants in these waters, although in some cases, the toxicity did not decrease. However, ozone as post-treatment permitted a further reduction of organic compounds, toxicity and COD. - Aerobic and anaerobic treatments remove organic compounds in paper mill effluents but toxicity remains

  3. The Study and Development of Metal Oxide Reactive Adsorbents for the Destruction of Toxic Organic Compounds

    National Research Council Canada - National Science Library

    Mitchell, Mark B

    2008-01-01

    ... and other toxic organic compounds. The research program that was developed built upon earlier results achieved in the room temperature oxidative decomposition of a chemical warfare agent simulant, dimethyl methylphosphonate (DMMP...

  4. The toxicity of oxidised DWCNTs to the aquatic organisms, and related causing mechanisms

    CSIR Research Space (South Africa)

    Lukhele, LP

    2013-08-01

    Full Text Available earlier reported for the three aquatic organisms in earlier scientific reports. Finally, the paper discusses the linkage between the toxicity mechanisms and the physicochemical properties of DWCNTs, namely: agglomeration state, surface chemistry...

  5. Source apportionment and health risk assessment of potentially toxic elements in road dust from urban industrial areas of Ahvaz megacity, Iran.

    Science.gov (United States)

    Najmeddin, Ali; Keshavarzi, Behnam; Moore, Farid; Lahijanzadeh, Ahmadreza

    2017-10-28

    This study investigates the occurrence and spatial distribution of potentially toxic elements (PTEs) (Hg, Cd, Cu, Mo, Pb, Zn, Ni, Co, Cr, Al, Fe, Mn, V and Sb) in 67 road dust samples collected from urban industrial areas in Ahvaz megacity, southwest of Iran. Geochemical methods, multivariate statistics, geostatistics and health risk assessment model were adopted to study the spatial pollution pattern and to identify the priority pollutants, regions of concern and sources of the studied PTEs. Also, receptor positive matrix factorization model was employed to assess pollution sources. Compared to the local background, the median enrichment factor values revealed the following order: Sb > Pb > Hg > Zn > Cu > V > Fe > Mo > Cd > Mn > Cr ≈ Co ≈ Al ≈ Ni. Statistical results show that a significant difference exists between concentrations of Mo, Cu, Pb, Zn, Fe, Sb, V and Hg in different regions (univariate analysis, Kruskal-Wallis test p matrix factorization model revealed that traffic-related emissions (43.5%) and steel industries (26.4%) were first two sources of PTEs in road dust, followed by natural sources (22.6%) and pipe and oil processing companies (7.5%). The arithmetic mean of pollution load index (PLI) values for high traffic sector (1.92) is greater than industrial (1.80) and residential areas (1.25). Also, the results show that ecological risk values for Hg and Pb in 41.8 and 9% of total dust samples are higher than 80, indicating their considerable or higher potential ecological risk. The health risk assessment model showed that ingestion of dust particles contributed more than 83% of the overall non-carcinogenic risk. For both residential and industrial scenarios, Hg and Pb had the highest risk values, whereas Mo has the lowest value.

  6. Toxicity of organic chemical pollution in groundwater downgradient of a landfill (Grindsted, Denmark)

    DEFF Research Database (Denmark)

    Baun, Anders; Jensen, S. D.; Bjerg, Poul Løgstrup

    2000-01-01

    The aim of the present study was to describe the occurrence and distribution of toxicity related to organic chemical contaminants in the leachate plume downgradient of the Grindsted Landfill (Denmark). A total of 27 groundwater samples were preconcentrated by solidphase extraction (SPE) using XAD-2...... bioassays, it was concluded that SPE extracts of groundwater collected close to the landfill were toxic. The toxicity decreased with the distance from the landfill. At distances greater than 80 m from the border of the landfill, the groundwater toxicity was not significantly different from the background...... characterization and hazard ranking of groundwater polluted with complex chemical mixtures, such as landfill leachates....

  7. Guanicid and PHMG Toxicity Tests on Aquatic Organisms

    OpenAIRE

    Eva Poštulková; Radovan Kopp

    2016-01-01

    The emergence and development of new algicidal products is caused by the ever increasing popularity of garden ponds as well as the use of these products in the fisheries sector, especially for disposal of cyanobacteria and algae. Most frequent means of combating cyanobacteria and algae are applications of algicidal substances. Newly developed algaecides include Guanicid and polyhexamethylene guanidine hydrochloride (PHMG). The aim of the study was to identify toxic effects of Guanicid and PHM...

  8. Effect of the waste products storage on the environmental pollution by toxic organic compounds

    Directory of Open Access Journals (Sweden)

    Aleksandra Lewkiewicz-Małysa

    2005-11-01

    Full Text Available A permanent deposition of industrial wastes is a method of its neutralization. A storage yard for toxic materials must meet specific site and construction conditions. The storage place region of toxic organic waste materials has to be monitored. The environmental impact of this waste on the groundwater quality, especially the migration of persistent organic pollutants, was discussed on the example of a chemical plant.

  9. FOR SELECTED ORGANIC MICROPOLLUTANTS ELIMINATION AND CHANGE OF WATER TOXICITY

    Directory of Open Access Journals (Sweden)

    Mariusz Dudziak

    2016-12-01

    Full Text Available All of the available and applicable chemical oxidants were found to affect the quality of the treated water or wastewater. It has been commonly observed that the oxidation processes generate by-products, which often possess unknown biological activity. Accordingly, the present study assessed the degree of degradation of mixture of selected micropollutants and the change of the solution toxicity in the UV/TiO2/H2O2 hybrid process. Water containing bisphenol A and diclofenac at a concentration of 1 mg/dm3 was treated. For toxicological evaluation of solution sample were used three different tests, ie. enzymatic Microtox® using luminescent strain of marine bacteria Aliivibrio fischeri, survival of the crustaceans Daphnia magna and the growth of duckweed Lemna minor. Decomposition of tested micropollutants depend on the processing time and the type of the oxidizing compound. However, during the process we observed adverse effects of water toxicity. The toxicity was documented in both bacteria and water plant.

  10. Typical halogenated persistent organic pollutants in indoor dust and the associations with childhood asthma in Shanghai, China

    International Nuclear Information System (INIS)

    Meng, Ge; Nie, Zhiqing; Feng, Yan; Wu, Xiaomeng; Yin, Yong; Wang, Yan

    2016-01-01

    Halogenated persistent organic pollutants (Hal-POPs) are significant contaminants in the indoor environment that are related to many human diseases. Ingestion of indoor dust is considered the major pathway of Hal-POP exposures, especially for children aged 3–6 years. Alongside a retrospective study on the associations between typical Hal-POP exposure and childhood asthma in Shanghai, indoor dust samples from asthmatic and non-asthmatic children's homes (n = 60, each) were collected. Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were measured by GC–MS. BDE-209, PCB-8 and p,p′-DDE were the predominant components in each chemical category. The concentrations of most Hal-POPs were significantly higher in the asthmatic families. The associations between Hal-POP exposure and asthma occurrence were examined by calculating the odds ratios (ORs) using a logistic regression model. A positive association was found between p,p′-DDE in indoor dust and childhood asthma (OR = 1.825, 95%CI: 1.004, 3.317; p = 0.048). The average daily doses of Hal-POP intake were calculated using the method provided by the USEPA. Non-carcinogenic health risks were preliminarily assessed. Our study indicated that exposure to p,p’-DDE via indoor dust may contribute to childhood asthma occurrence. Non-carcinogenic health risks were not found with the intake of Hal-POPs via the ingestion of indoor dust. - Highlights: • Three POP species were measured in indoor dust from the homes of asthmatic and non-asthmatic children. • The concentrations of BDE-47/-99/-209, PCB-8/-49 and p,p’-DDE were significantly higher in the case group. • p,p′-DDE showed positive association with childhood asthma occurrence. • Hal-POP exposure via ingestion of indoor dust was not associated with non-carcinogenic health risks. - The concentrations of select Hal-POPs in dust were determined, and a positive association was found between p

  11. Bioremediation of Heavy Metals and Organic Toxicants by Composting

    Directory of Open Access Journals (Sweden)

    Allen V. Barker

    2002-01-01

    Full Text Available Hazardous organic and metallic residues or by-products can enter into plants, soils, and sediments from processes associated with domestic, municipal, agricultural, industrial, and military activities. Handling, ingestion, application to land or other distributions of the contaminated materials into the environment might render harm to humans, livestock, wildlife, crops, or native plants. Considerable remediation of the hazardous wastes or contaminated plants, soils, and sediments can be accomplished by composting. High microbial diversity and activity during composting, due to the abundance of substrates in feedstocks, promotes degradation of xenobiotic organic compounds, such as pesticides, polycyclic aromatic hydrocarbons (PAHs, and polychlorinated biphenyls (PCBs. For composting of contaminated soils, noncontaminated organic matter should be cocomposted with the soils. Metallic pollutants are not degraded during composting but may be converted into organic combinations that have less bioavailability than mineral combinations of the metals. Degradation of organic contaminants in soils is facilitated by addition of composted or raw organic matter, thereby increasing the substrate levels for cometabolism of the contaminants. Similar to the composting of soils in vessels or piles, the on-site addition of organic matter to soils (sheet composting accelerates degradation of organic pollutants and binds metallic pollutants. Recalcitrant materials, such as organochlorines, may not undergo degradation in composts or in soils, and the effects of forming organic complexes with metallic pollutants may be nonpermanent or short lived. The general conclusion is, however, that composting degrades or binds pollutants to innocuous levels or into innocuous compounds in the finished product.

  12. A Raman spectroscopic study of organic matter in interplanetary dust particles and meteorites using multiple wavelength laser excitation

    OpenAIRE

    Starkey, N. A.; Franchi, I. A.; Alexander, C. M. O'D.

    2013-01-01

    Raman spectroscopy was used to investigate insoluble organic matter (IOM) from a range of chondritic meteorites, and a suite of interplanetary dust particles (IDPs). Three monochromatic excitation wavelengths (473 nm, 514 nm, 632 nm) were applied sequentially to assess variations in meteorite and IDP Raman peak parameters (carbon D and G bands) as a function of excitation wavelength (i.e., dispersion). Greatest dispersion occurs in CVs > OCs > CMs > CRs with type 3 chondrites compared at diff...

  13. Promotion Effect of Asian Dust on Phytoplankton Growth and Potential Dissolved Organic Phosphorus Utilization in the South China Sea

    Science.gov (United States)

    Chu, Qiang; Liu, Ying; Shi, Jie; Zhang, Chao; Gong, Xiang; Yao, Xiaohong; Guo, Xinyu; Gao, Huiwang

    2018-03-01

    Dust deposition is an important nutrient source to the South China Sea (SCS), but few in situ experiments were conducted on phytoplankton response to the deposition. We conducted onboard incubation experiments at three stations near Luzon Strait in the SCS, with addition of multiple dissolved inorganic nutrients, Asian dust, and rainwater. From our results, nitrogen and phosphorus were both urgently needed for phytoplankton growth in the SCS, indicated by the evident Chl a response to the addition of nitrogen and phosphorus together. Almost no evident response was observed by adding phosphorus or iron alone to incubation waters, although a delayed response of Chl a in mass concentration was observed by adding nitrogen alone. The latter implied a possible utilization of dissolved organic phosphorus because of insufficient dissolved inorganic phosphorus in incubation waters. Under such nutrient condition, Asian dust showed an apparent promotion effect on phytoplankton growth by providing sufficient amounts of nitrogen but low phosphorus. Meanwhile, it was found that large sized (> 5 μm) phytoplankton community showed different responses to dust addition at different stations. At stations A3 and A6, Chaetoceros spp. became the dominant species during the bloom period, while at station WG2, Nitzschia spp. became dominant. In combination with different initial nutrients and Chl a levels at the three stations, the different phytoplankton community evolution implied the response difference to external inputs between oligotrophic (stations A3 and A6) and ultraoligotrophic (station WG2) conditions in the SCS.

  14. Guanicid and PHMG Toxicity Tests on Aquatic Organisms

    Directory of Open Access Journals (Sweden)

    Eva Poštulková

    2016-01-01

    Full Text Available The emergence and development of new algicidal products is caused by the ever increasing popularity of garden ponds as well as the use of these products in the fisheries sector, especially for disposal of cyanobacteria and algae. Most frequent means of combating cyanobacteria and algae are applications of algicidal substances. Newly developed algaecides include Guanicid and polyhexamethylene guanidine hydrochloride (PHMG. The aim of the study was to identify toxic effects of Guanicid and PHMG on zebrafish (Danio rerio and green algae (Desmodesmus communis. We determined the acute toxicity in fish according to ČSN EN ISO 7346-1, and conducted the freshwater algae growth inhibition test according to ČSN ISO 8692 methodology. For inhibition tests with green algae we chose Guanicid and PHMG concentrations of 0.001, 0.005, and 0.010 ml/L. For fish short-term acute toxicity tests we chose Guanicid concentrations of 0.010, 0.050, 0.150, 0.200, 0.250, and 0.300 ml/L and PHMG concentrations of 0.010, 0.025, 0.050, 0.075, 0.100, and 0.125 ml/L. In case of zebrafish (Danio rerio, the LC50 value for Guanicid is 0.086 ml/L, while the LC50 value for PHMG is 0.043 ml/L. Effects of Guanicid on inhibition of green algae (Desmodesmus communis appear highly significant (p < 0.010 at a concentration of 0.010 ml/L. For PHMG, these effects are highly significant (p < 0.001 at concentrations of 0.005 and 0.010 ml/L in 48 hours.

  15. Impacts of select organic ligands on the colloidal stability, dissolution dynamics, and toxicity of silver nanoparticles.

    Science.gov (United States)

    Pokhrel, Lok R; Dubey, Brajesh; Scheuerman, Phillip R

    2013-11-19

    Key understanding of potential transformations that may occur on silver nanoparticle (AgNP) surface upon interaction with naturally ubiquitous organic ligands (e.g., -SH (thoil), humic acid, or -COO (carboxylate)) is limited. Herein we investigated how dissolved organic carbon (DOC), -SH (in cysteine, a well-known Ag(+) chelating agent), and -COO (in trolox, a well-known antioxidant) could alter the colloidal stability, dissolution rate, and toxicity of citrate-functionalized AgNPs (citrate-AgNPs) against a keystone crustacean Daphnia magna. Cysteine, DOC, or trolox amendment of citrate-AgNPs differentially modified particle size, surface properties (charge, plasmonic spectra), and ion release dynamics, thereby attenuating (with cysteine or trolox) or promoting (with DOC) AgNP toxicity. Except with DOC amendment, the combined toxicity of AgNPs and released Ag under cysteine or trolox amendment was lower than of AgNO3 alone. The results of this study show that citrate-AgNP toxicity can be associated with oxidative stress, ion release, and the organism biology. Our evidence suggests that specific organic ligands available in the receiving waters can differentially surface modify AgNPs and alter their environmental persistence (changing dissolution dynamics) and subsequently the toxicity; hence, we caveat to generalize that surface modified nanoparticles upon environmental release may not be toxic to receptor organisms.

  16. Trends in phytoremediation of toxic elemental and organic pollutants

    African Journals Online (AJOL)

    OHWESIRI IBUJE

    2010-09-13

    Sep 13, 2010 ... interactions and other rhizosphere processes, plant uptake .... protein and they play important role in deciding plant's tolerance to .... molecular biology, vol. 107. Totawa, NJ: .... Simulation of organic processes. Boca Raton, FL: ...

  17. Stabilization of dissolved organic matter by aluminium: A toxic effect or stabilization through precipitation?

    NARCIS (Netherlands)

    Scheel, T.; Jansen, B.; van Wijk, A.J.; Verstraten, J.M.; Kalbitz, K.

    2008-01-01

    Carbon mineralization in acidic forest soils can be retarded by large concentrations of aluminium (Al). However, it is still unclear whether Al reduces C mineralization by direct toxicity to microorganisms or by decreased bioavailability of organic matter (OM) because dissolved organic matter (DOM)

  18. Pattern Recognition Scavenger Receptor A/CD204 Regulates Airway Inflammatory Homeostasis Following Organic Dust Extract Exposures

    Science.gov (United States)

    Poole, Jill A.; Anderson, Leigh; Gleason, Angela M.; West, William W.; Romberger, Debra J.; Wyatt, Todd A.

    2014-01-01

    Exposure to agriculture organic dusts, comprised of a diversity of pathogen-associated molecular patterns, results in chronic airway diseases. The multi-functional class A macrophage scavenger receptor (SRA)/CD204 has emerged as an important class of pattern recognition receptors with broad ligand binding ability. Our objective was to determine the role of SRA in mediating repetitive and post-inflammatory organic dust extract (ODE)-induced airway inflammation. Wild-type (WT) and SRA knockout (KO) mice were intra-nasally treated with ODE or saline daily for 3 wk and immediately euthanized or allowed to recover for 1 wk. Results show that lung histopathologic changes were increased in SRA KO mice as compared to WT following repetitive ODE exposures marked predominately by increased size and distribution of lymphoid aggregates. After a 1-wk recovery from daily ODE treatments, there was significant resolution of lung injury in WT mice, but not SRA KO animals. The increased lung histopathology induced by ODE treatment was associated with decreased accumulation of neutrophils, but greater accumulation of CD4+ T-cells. The lung cytokine milieu induced by ODE was consistent with a TH1/TH17 polarization in both WT and SRA KO mice. Overall, our data demonstrate that SRA/CD204 plays an important role in the normative inflammatory lung response to ODE as evidenced by the enhanced dust-mediated injury viewed in the absence of this receptor. PMID:24491035

  19. Evaluation of the toxicity of organic matter in marine sediments

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.

    The inhibitory effects of the organics from the sediment along the east coast of India on acetylcholinesterase (AChE) in-vitro were evaluated. Sediment samples collected from the surface layers at various depths were extracted. Each of the extracts...

  20. Spatiotemporal drivers of dissolved organic matter in high alpine lakes: Role of Saharan dust inputs and bacterial activity.

    Science.gov (United States)

    Mladenov, Natalie; Pulido-Villena, Elvira; Morales-Baquero, Rafael; Ortega-Retuerta, Eva; Sommaruga, Ruben; Reche, Isabel

    2008-01-01

    The effects of many environmental stressors such as UV radiation are mediated by dissolved organic matter (DOM) properties. Therefore, determining the factors shaping spatial and temporal patterns is particularly essential in the most susceptible, low dissolved organic carbon (DOC) lakes. We analyzed spatiotemporal variations in dissolved organic carbon concentration and dissolved organic matter optical properties (absorption and fluorescence) in 11 transparent lakes located above tree line in the Sierra Nevada Mountains (Spain), and we assessed potential external (evaporation and atmospheric deposition) and internal (bacterial abundance, bacterial production, chlorophyll a, and catchment vegetation) drivers of DOM patterns. At spatial and temporal scales, bacteria were related to chromophoric DOM (CDOM). At the temporal scale, water soluble organic carbon (WSOC) in dust deposition and evaporation were found to have a significant influence on DOC and CDOM in two Sierra Nevada lakes studied during the ice-free periods of 2000-2002. DOC concentrations and absorption coefficients at 320 nm were strongly correlated over the spatial scale (n = 11, R(2) = 0.86; p DOC concentration and CDOM to these factors. At the continental scale, higher mean DOC concentrations and more CDOM in lakes of the Sierra Nevada than in lakes of the Pyrenees and Alps may be due to a combination of more extreme evaporation, and greater atmospheric dust deposition.

  1. Toxicity assessment of volatile organic compounds and polycyclic aromatic hydrocarbons in motorcycle exhaust

    International Nuclear Information System (INIS)

    Chang, C.-T.; Chen, B.-Y.

    2008-01-01

    This study investigates the toxicity of various pollutant species from motorcycle exhaust via dose-response analysis and margin of safety using Escherichia coli DH5α. The toxicity evaluation of the major components of motorcycle exhaust volatile organic compounds (VOCs), collected with impinger, and polycyclic aromatic hydrocarbons (PAHs), collected with filter and XAD-2, is essential to determine emission standards for motorcycles. The toxicity of benzene (B), toluene (T), ethyl benzene (E) and xylene (X) was selected for comparison as standard VOCs emitted from motorcycles. In addition, three types of reformulated gasoline (high oxygenate and high benzene content (No. 1), low oxygen and high benzene (No. 2), and low oxygen and low benzene (No. 3) were prepared to reveal combined toxicity of individual compositions. Motorcycle exhaust is significantly more toxic than BTEX due to the highly toxic VOCs generated from incomplete combustion. Overall toxicity evaluation showed that the toxicity, indicated as EC 50 , was approximately as follows: PAHs > two-stroke engines > four-stroke engines > BTEX

  2. Toxicity assessment of volatile organic compounds and polycyclic aromatic hydrocarbons in motorcycle exhaust.

    Science.gov (United States)

    Chang, Chang-Tang; Chen, Bor-Yann

    2008-05-30

    This study investigates the toxicity of various pollutant species from motorcycle exhaust via dose-response analysis and margin of safety using Escherichia coli DH5 alpha. The toxicity evaluation of the major components of motorcycle exhaust volatile organic compounds (VOCs), collected with impinger, and polycyclic aromatic hydrocarbons (PAHs), collected with filter and XAD-2, is essential to determine emission standards for motorcycles. The toxicity of benzene (B), toluene (T), ethyl benzene (E) and xylene (X) was selected for comparison as standard VOCs emitted from motorcycles. In addition, three types of reformulated gasoline (high oxygenate and high benzene content (No. 1), low oxygen and high benzene (No. 2), and low oxygen and low benzene (No. 3) were prepared to reveal combined toxicity of individual compositions. Motorcycle exhaust is significantly more toxic than BTEX due to the highly toxic VOCs generated from incomplete combustion. Overall toxicity evaluation showed that the toxicity, indicated as EC50, was approximately as follows: PAHs>two-stroke engines>four-stroke engines>BTEX.

  3. Characterisation of atmospheric deposited particles during a dust storm in urban areas of Eastern Australia

    Energy Technology Data Exchange (ETDEWEB)

    Gunawardena, Janaka, E-mail: j.gunawardena@qut.edu.au; Ziyath, Abdul M., E-mail: mohamed.ziyath@qut.edu.au; Bostrom, Thor E., E-mail: t.bostrom@qut.edu.au; Bekessy, Lambert K., E-mail: l.bekessy@qut.edu.au; Ayoko, Godwin A., E-mail: g.ayoko@qut.edu.au; Egodawatta, Prasanna, E-mail: p.egodawatta@qut.edu.au; Goonetilleke, Ashantha, E-mail: a.goonetilleke@qut.edu.au

    2013-09-01

    The characteristics of dust particles deposited during the 2009 dust storm in the Gold Coast and Brisbane regions of Australia are discussed in this paper. The study outcomes provide important knowledge in relation to the potential impacts of dust storm related pollution on ecosystem health in the context that the frequency of dust storms is predicted to increase due to anthropogenic desert surface modifications and climate change impacts. The investigated dust storm contributed a large fraction of fine particles to the environment with an increased amount of total suspended solids, compared to dry deposition under ambient conditions. Although the dust storm passed over forested areas, the organic carbon content in the dust was relatively low. The primary metals present in the dust storm deposition were aluminium, iron and manganese, which are common soil minerals in Australia. The dust storm deposition did not contain significant loads of nickel, cadmium, copper and lead, which are commonly present in the urban environment. Furthermore, the comparison between the ambient and dust storm chromium and zinc loads suggested that these metals were contributed to the dust storm by local anthropogenic sources. The potential ecosystem health impacts of the 2009 dust storm include, increased fine solids deposition on ground surfaces resulting in an enhanced capacity to adsorb toxic pollutants as well as increased aluminium, iron and manganese loads. In contrast, the ecosystem health impacts related to organic carbon and other metals from dust storm atmospheric deposition are not considered to be significant. - Highlights: • The dust storm contributed a large fraction of fine particles to pollutant build-up. • The dust storm increased TSS, Al, Fe and Mn loads in build-up on ground surfaces. • Dust storm did not significantly increase TOC, Ni, Cu, Pb and Cd loads in build-up. • Cr and Zn in dust storm deposition were contributed by local anthropogenic sources.

  4. Characterisation of atmospheric deposited particles during a dust storm in urban areas of Eastern Australia

    International Nuclear Information System (INIS)

    Gunawardena, Janaka; Ziyath, Abdul M.; Bostrom, Thor E.; Bekessy, Lambert K.; Ayoko, Godwin A.; Egodawatta, Prasanna; Goonetilleke, Ashantha

    2013-01-01

    The characteristics of dust particles deposited during the 2009 dust storm in the Gold Coast and Brisbane regions of Australia are discussed in this paper. The study outcomes provide important knowledge in relation to the potential impacts of dust storm related pollution on ecosystem health in the context that the frequency of dust storms is predicted to increase due to anthropogenic desert surface modifications and climate change impacts. The investigated dust storm contributed a large fraction of fine particles to the environment with an increased amount of total suspended solids, compared to dry deposition under ambient conditions. Although the dust storm passed over forested areas, the organic carbon content in the dust was relatively low. The primary metals present in the dust storm deposition were aluminium, iron and manganese, which are common soil minerals in Australia. The dust storm deposition did not contain significant loads of nickel, cadmium, copper and lead, which are commonly present in the urban environment. Furthermore, the comparison between the ambient and dust storm chromium and zinc loads suggested that these metals were contributed to the dust storm by local anthropogenic sources. The potential ecosystem health impacts of the 2009 dust storm include, increased fine solids deposition on ground surfaces resulting in an enhanced capacity to adsorb toxic pollutants as well as increased aluminium, iron and manganese loads. In contrast, the ecosystem health impacts related to organic carbon and other metals from dust storm atmospheric deposition are not considered to be significant. - Highlights: • The dust storm contributed a large fraction of fine particles to pollutant build-up. • The dust storm increased TSS, Al, Fe and Mn loads in build-up on ground surfaces. • Dust storm did not significantly increase TOC, Ni, Cu, Pb and Cd loads in build-up. • Cr and Zn in dust storm deposition were contributed by local anthropogenic sources

  5. Dust evolution, a global view: III. Core/mantle grains, organic nano-globules, comets and surface chemistry

    Science.gov (United States)

    2016-01-01

    Within the framework of The Heterogeneous dust Evolution Model for Interstellar Solids (THEMIS), this work explores the surface processes and chemistry relating to core/mantle interstellar and cometary grain structures and their influence on the nature of these fascinating particles. It appears that a realistic consideration of the nature and chemical reactivity of interstellar grain surfaces could self-consistently and within a coherent framework explain: the anomalous oxygen depletion, the nature of the CO dark gas, the formation of ‘polar ice’ mantles, the red wing on the 3 μm water ice band, the basis for the O-rich chemistry observed in hot cores, the origin of organic nano-globules and the 3.2 μm ‘carbonyl’ absorption band observed in comet reflectance spectra. It is proposed that the reaction of gas phase species with carbonaceous a-C(:H) grain surfaces in the interstellar medium, in particular the incorporation of atomic oxygen into grain surfaces in epoxide functional groups, is the key to explaining these observations. Thus, the chemistry of cosmic dust is much more intimately related with that of the interstellar gas than has previously been considered. The current models for interstellar gas and dust chemistry will therefore most likely need to be fundamentally modified to include these new grain surface processes. PMID:28083090

  6. Toxicity of anthelmintic drugs (fenbendazole and flubendazole) to aquatic organisms.

    Science.gov (United States)

    Wagil, Marta; Białk-Bielińska, Anna; Puckowski, Alan; Wychodnik, Katarzyna; Maszkowska, Joanna; Mulkiewicz, Ewa; Kumirska, Jolanta; Stepnowski, Piotr; Stolte, Stefan

    2015-02-01

    Flubendazole (FLU) and fenbendazole (FEN) belong to benzimidazoles-pharmaceuticals widely used in veterinary and human medicine for the treatment of intestinal parasites as well as for the treatment of systemic worm infections. In recent years, usage of these drugs increased, which resulted in a larger contamination of the environment and possible negative effects on biota. Hence, in our research, we investigated an aquatic ecotoxicity of these pharmaceuticals towards: marine bacteria (Vibrio fischeri), green algae (Scenedesmus vacuolatus), duckweed (Lemna minor) and crustacean (Daphnia magna). Ecotoxicity tests were combined with chemical analysis in order to investigate the actual exposure concentration of the compounds used in the experiment as well as to stability and adsorption studies. As a result, study evaluating sensitivity of different aquatic organisms to these compounds and new ecotoxicological data is presented. The strongest negative impact of FLU and FEN was observed to D. magna.

  7. A Novel Multi-Approach Protocol for the Characterization of Occupational Exposure to Organic Dust-Swine Production Case Study.

    Science.gov (United States)

    Viegas, Carla; Faria, Tiago; Monteiro, Ana; Caetano, Liliana Aranha; Carolino, Elisabete; Quintal Gomes, Anita; Viegas, Susana

    2017-12-27

    Swine production has been associated with health risks and workers' symptoms. In Portugal, as in other countries, large-scale swine production involves several activities in the swine environment that require direct intervention, increasing workers' exposure to organic dust. This study describes an updated protocol for the assessment of occupational exposure to organic dust, to unveil an accurate scenario regarding occupational and environmental risks for workers' health. The particle size distribution was characterized regarding mass concentration in five different size ranges (PM0.5, PM1, PM2.5, PM5, PM10). Bioburden was assessed, by both active and passive sampling methods, in air, on surfaces, floor covering and feed samples, and analyzed through culture based-methods and qPCR. Smaller size range particles exhibited the highest counts, with indoor particles showing higher particle counts and mass concentration than outdoor particles. The limit values suggested for total bacteria load were surpassed in 35.7% (10 out of 28) of samples and for fungi in 65.5% (19 out of 29) of samples. Among Aspergillus genera, section Circumdati was the most prevalent (55%) on malt extract agar (MEA) and Versicolores the most identified (50%) on dichloran glycerol (DG18). The results document a wide characterization of occupational exposure to organic dust on swine farms, being useful for policies and stakeholders to act to improve workers' safety. The methods of sampling and analysis employed were the most suitable considering the purpose of the study and should be adopted as a protocol to be followed in future exposure assessments in this occupational environment.

  8. Evaluation of Levels, Sources and Health Hazards of Road-Dust Associated Toxic Metals in Jalalabad and Kabul Cities, Afghanistan.

    Science.gov (United States)

    Jadoon, Waqar Azeem; Khpalwak, Wahdatullah; Chidya, Russel Chrispine Garven; Abdel-Dayem, Sherif Mohamed Mohamed Ali; Takeda, Kazuhiko; Makhdoom, Masood Arshad; Sakugawa, Hiroshi

    2018-01-01

    This study was designed to investigate selected road-dust associated heavy metals, their relations with natural and anthropogenic sources, and potential human and environmental health risks. For this purpose, 42 and 36 road-dusts samples were collected from Jalalabad and Kabul cities (Afghanistan), respectively. The following elements were found in descending concentrations: Mn, Zn, Pb, Ni, Cu, Cr, Co, and Cd in Jalalabad; and Mn, Zn, Ni, Cu, Cr, Pb, Co, and Cd in Kabul. Except for Ni, all the elemental contents were less than the Canadian permissible limits in residential/parkland soils. Principle Component Analysis and enrichment of Cd, Cu, Ni, Pb, and Zn pointed to anthropogenic sources, whereas Co, Cr, and Mn indicated crustal inputs. Broadly, Cd monomial risk index ([Formula: see text]) was considerable; however, one site each in both cities showed high risk ([Formula: see text] ≥ 350). The potential ecological risk (RI) is mostly low; however, at some sites, the risk was considerable. Ingestion appeared to be the main exposure route (99%) for heavy metals and contributed > 90% to noncancerous (all residents), as well as 92% (children) and 75-89% (adults) cancerous risks. The noncancerous risks of all metals and their integrated risks for all residents were within acceptable levels. Moreover, potential cancer risks in children from Ni and Cr were slightly higher than the US-EPA safe levels but were within acceptable levels for adults. This study found higher risks to children and therefore recommends proper management and ways to control metals pollution load in these areas to decrease human health and RIs.

  9. Fate of petroleum hydrocarbons and toxic organics in Louisiana coastal environments

    International Nuclear Information System (INIS)

    DeLaune, R.D.; Gambrell, R.P.; Pardue, J.H.; Patrick, W.H. Jr.

    1991-01-01

    Numerous potentially toxic compounds are entering Louisiana's inshore and nearshore coastal environments. To a large degree there is insufficient information for predicting the fate and effect of these materials in aquatic environments. Studies documenting the impact of petroleum hydrocarbons entering Louisiana coastal wetlands are summarized. Also included are research findings on factors affecting the persistence of petroleum hydrocarbons and other toxic organics (pentachlorophenol (PCP), 2,4-dichlorophenoxyacetic acid (2,4-D), creosote, etc.) in sediment-water systems. Sediment pH and redox conditions have been found to play an important role in the microbial degradation of toxic organics. Most of the hydrocarbons investigated degrade more rapidly under high redox (aerobic) conditions although there are exceptions (e.g., 1,1,1-trichloro-2,2-bis(4-chlorophenyl)(DDT) and polychlorobiphenyls (PCBs)). Some of these compounds, due to their slow degradation in anaerobic sediment, may persist in the system for decades

  10. Chronic toxicity of sediment-associated linear alkylbenzene sulphonates (LAS) to freshwater benthic organisms

    Energy Technology Data Exchange (ETDEWEB)

    Comber, S.D.W. [WRc-NSF, Henley Road, Medmenham, Marlow, Buckinghamshire, SL7 2HD (United Kingdom)]. E-mail: sean.comber@atkinsglobal.com; Conrad, A.U. [Weinberg Group, Blue Tower, Box 16, B-1050 Brussels (Belgium); Hoess, S. [ECOSSA, Thierschstrasser 43, 80538, Muenchen (Germany); Webb, S. [CEFIC, Ave E. Van Nieuwenhuyse 4, B-1160 Brussels (Belgium); Marshall, S. [Unilever Research, Environment Centre, Bebington, Wirral, Merseyside, L63 3JW (United Kingdom)

    2006-11-15

    The toxicity of linear alkylbenzene sulphonates (LAS), to freshwater benthic organisms was assessed during exposure to spiked sediment. Lethal and sub-lethal end-points were monitored for two organisms (oligochaete Lumbriculus variegatus and nematode Caenorhabditis elegans). Results demonstrated relatively low toxicity (LOECs >100 mg/kg dry weight). No observed effect concentrations (NOECs) of 81 mg/kg dw (Lumbriculus) and 100 mg/kg dw (Caenorhabditis) were determined. For the oligochaete, no specific endpoint was particularly sensitive to LAS. For the nematode, egg production was the most sensitive endpoint. Significant degradation was measured over the 28-day duration of the Lumbriculus study, equating to a half-life of 20 days in sediment. - This paper provides sediment toxicity data for LAS, essential for a detailed and accurate environment risk assessment.

  11. Chronic toxicity of sediment-associated linear alkylbenzene sulphonates (LAS) to freshwater benthic organisms

    International Nuclear Information System (INIS)

    Comber, S.D.W.; Conrad, A.U.; Hoess, S.; Webb, S.; Marshall, S.

    2006-01-01

    The toxicity of linear alkylbenzene sulphonates (LAS), to freshwater benthic organisms was assessed during exposure to spiked sediment. Lethal and sub-lethal end-points were monitored for two organisms (oligochaete Lumbriculus variegatus and nematode Caenorhabditis elegans). Results demonstrated relatively low toxicity (LOECs >100 mg/kg dry weight). No observed effect concentrations (NOECs) of 81 mg/kg dw (Lumbriculus) and 100 mg/kg dw (Caenorhabditis) were determined. For the oligochaete, no specific endpoint was particularly sensitive to LAS. For the nematode, egg production was the most sensitive endpoint. Significant degradation was measured over the 28-day duration of the Lumbriculus study, equating to a half-life of 20 days in sediment. - This paper provides sediment toxicity data for LAS, essential for a detailed and accurate environment risk assessment

  12. Historic records of organic compounds from a high Alpine glacier: influences of biomass burning, anthropogenic emissions, and dust transport

    Directory of Open Access Journals (Sweden)

    C. Müller-Tautges

    2016-01-01

    Full Text Available Historic records of α-dicarbonyls (glyoxal, methylglyoxal, carboxylic acids (C6–C12 dicarboxylic acids, pinic acid, p-hydroxybenzoic acid, phthalic acid, 4-methylphthalic acid, and ions (oxalate, formate, calcium were determined with annual resolution in an ice core from Grenzgletscher in the southern Swiss Alps, covering the time period from 1942 to 1993. Chemical analysis of the organic compounds was conducted using ultra-high-performance liquid chromatography (UHPLC coupled to electrospray ionization high-resolution mass spectrometry (ESI-HRMS for dicarbonyls and long-chain carboxylic acids and ion chromatography for short-chain carboxylates. Long-term records of the carboxylic acids and dicarbonyls, as well as their source apportionment, are reported for western Europe. This is the first study comprising long-term trends of dicarbonyls and long-chain dicarboxylic acids (C6–C12 in Alpine precipitation. Source assignment of the organic species present in the ice core was performed using principal component analysis. Our results suggest biomass burning, anthropogenic emissions, and transport of mineral dust to be the main parameters influencing the concentration of organic compounds. Ice core records of several highly correlated compounds (e.g., p-hydroxybenzoic acid, pinic acid, pimelic, and suberic acids can be related to the forest fire history in southern Switzerland. P-hydroxybenzoic acid was found to be the best organic fire tracer in the study area, revealing the highest correlation with the burned area from fires. Historical records of methylglyoxal, phthalic acid, and dicarboxylic acids adipic acid, sebacic acid, and dodecanedioic acid are comparable with that of anthropogenic emissions of volatile organic compounds (VOCs. The small organic acids, oxalic acid and formic acid, are both highly correlated with calcium, suggesting their records to be affected by changing mineral dust transport to the drilling site.

  13. Toxicity of strontium-90 depending on the way of its administration to animal organisms

    International Nuclear Information System (INIS)

    Shvedov, V.L.

    1978-01-01

    Toxicity of strontium-90 administered orally is almost thrice lower than that after parenteral administration. The values of the doses absorbed in the critical organ of rats, corresponding to LDsub(50/30), were 2400 to 2600 rad irrespective of the route of the radionuclide administration

  14. Risk of Adverse Health and Performance Effects of Celestial Dust Exposure

    Science.gov (United States)

    Scully, Robert R.; Meyers, Valerie E.

    2015-01-01

    silica (Permissible Exposure Limit [PEL] 0.05 mg/m3) but more toxic than the nuisance dust titanium dioxide (TiO2 [PEL 5.0 mg/m3]). A PEL for episodic exposure to airborne lunar dust during a six-month stay on the lunar surface was established, in consultation with an independent, extramural panel of expert pulmonary toxicologists, at 0.3 mg/m3. The PEL provided for lunar dust is limited to the conditions and exposure specified therefore additional research remains to be accomplished with lunar dust to further address the issues of activation, address other areas of more unique lunar geology (Glotch et al., 2010; Greenhagen et al., 2010), examine potential toxicological effects of inhaled or ingested dust upon other organ systems, such cardiovascular, nervous systems, and examine effects of acute exposure to massive doses of dust such as may occur during off-nominal situations. Work to support the establishment of PELs for Martian dust and dusts of asteroids remains to be accomplished. The literature that describes health effects of exposure to toxic terrestrial dusts provides substantial basis for concern that prolonged exposure to respirable celestial dust could be detrimental to human health. Celestial bodies where a substantial portion of the dust is in the respirable range or where the dusts have large reactive surface areas or contain transition metals or volatile organics, represent greater risks of adverse effects from exposure to the dust. It is possible that in addition to adverse effects to the respiratory system, inhalation and ingestion of celestial dusts could pose risks to other systems

  15. Organic anion transporter (Slc22a) family members as mediators of toxicity

    International Nuclear Information System (INIS)

    Sweet, Douglas H.

    2005-01-01

    Exposure of the body to toxic organic anions is unavoidable and occurs from both intentional and unintentional sources. Many hormones, neurotransmitters, and waste products of cellular metabolism, or their metabolites, are organic anions. The same is true for a wide variety of medications, herbicides, pesticides, plant and animal toxins, and industrial chemicals and solvents. Rapid and efficient elimination of these substances is often the body's best defense for limiting both systemic exposure and the duration of their pharmacological or toxicological effects. For organic anions, active transepithelial transport across the renal proximal tubule followed by elimination via the urine is a major pathway in this detoxification process. Accordingly, a large number of organic anion transport proteins belonging to several different gene families have been identified and found to be expressed in the proximal nephron. The function of these transporters, in combination with the high volume of renal blood flow, predisposes the kidney to increased toxic susceptibility. Understanding how the kidney mediates the transport of organic anions is integral to achieving desired therapeutic outcomes in response to drug interactions and chemical exposures, to understanding the progression of some disease states, and to predicting the influence of genetic variation upon these processes. This review will focus on the organic anion transporter (OAT) family and discuss the known members, their mechanisms of action, subcellular localization, and current evidence implicating their function as a determinant of the toxicity of certain endogenous and xenobiotic agents

  16. Acute and chronic toxicity of boron to a variety of freshwater organisms.

    Science.gov (United States)

    Soucek, David J; Dickinson, Amy; Koch, Brian T

    2011-08-01

    Boron enters the aquatic environment from various sources, including weathering of borates, sewage effluents, coal combustion, use of cleaning compounds, and agrochemicals. The present study was designed to generate data on acute and chronic boron toxicity in support of an update of water quality standards in Illinois, USA. We examined the acute toxicity of boron to eight different freshwater organisms including a fish, an insect, two crustaceans, and four bivalve mollusks. To our knowledge, this is the first study to present data on the toxicity of boron to freshwater mollusks. We also sought to clarify whether hardness or pH affect boron toxicity to aquatic life, and to quantify chronic effect levels in two freshwater species. Sensitivity among the various species ranged widely, with the fathead minnow (Pimephales promelas) being the most sensitive. Neither pH nor hardness had a consistent effect on acute boron toxicity to two crustaceans (Ceriodaphnia dubia and Hyalella azteca), but we observed evidence that chloride reduces boron toxicity to H. azteca. The fathead minnow, while more acutely sensitive than the other species, had a lower acute to chronic ratio than did H. azteca, which had reduced reproduction at 13 mg/L. While we do not know the extent to which the eight tested species represent the range of sensitivities of native but untested species in Illinois, the current water quality standard for Illinois (1 mg/L) is conservative with regard to the native species tested thus far. Copyright © 2011 SETAC.

  17. Copper toxicity and organic matter: Resiliency of watersheds in the Duluth Complex, Minnesota, USA

    Science.gov (United States)

    Piatak, Nadine; Seal, Robert; Jones, Perry M.; Woodruff, Laurel G.

    2015-01-01

    We estimated copper (Cu) toxicity in surface water with high dissolved organic matter (DOM) for unmined mineralized watersheds of the Duluth Complex using the Biotic Ligand Model (BLM), which evaluates the effect of DOM, cation competition for biologic binding sites, and metal speciation. A sediment-based BLM was used to estimate stream-sediment toxicity; this approach factors in the cumulative effects of multiple metals, incorporation of metals into less bioavailable sulfides, and complexation of metals with organic carbon. For surface water, the formation of Cu-DOM complexes significantly reduces the amount of Cu available to aquatic organisms. The protective effects of cations, such as calcium (Ca) and magnesium (Mg), competing with Cu to complex with the biotic ligand is likely not as important as DOM in water with high DOM and low hardness. Standard hardness-based water quality criteria (WQC) are probably inadequate for describing Cu toxicity in such waters and a BLM approach may yield more accurate results. Nevertheless, assumptions about relative proportions of humic acid (HA) and fulvic acid (FA) in DOM significantly influence BLM results; the higher the HA fraction, the higher calculated resiliency of the water to Cu toxicity. Another important factor is seasonal variation in water chemistry, with greater resiliency to Cu toxicity during low flow compared to high flow.Based on generally low total organic carbon and sulfur content, and equivalent metal ratios from total and weak partial extractions, much of the total metal concentration in clastic streambedsediments may be in bioavailable forms, sorbed on clays or hydroxide phases. However, organicrich fine-grained sediment in the numerous wetlands may sequester significant amount of metals, limiting their bioavailability. A high proportion of organic matter in waters and some sediments will play a key role in the resiliency of these watersheds to potential additional metal loads associated with future

  18. Toxicity of aluminium in natural waters controlled by type rather than quantity of natural organic matter

    International Nuclear Information System (INIS)

    Papathanasiou, Grigorios; White, Keith N.; Walton, Rachel; Boult, Stephen

    2011-01-01

    Extension of the conditions under which Al toxicity is tested is required. Environmentally representative preparation of waters is used in investigating roles of alginate (AA) and humic acids (HA) in partitioning of Al (0.5 mg L -1 ), subsequent uptake and accumulation by and toxicity to Lymnaea stagnalis. HA and AA did not alter precipitation of Al(OH) 3 , but altered subsequent behaviour of Al. High (40 mg L -1 ) HA concentrations, and to a lesser extent AA, prevented settling and availability for benthic grazing but made deposited Al more likely to be ingested. HA detoxified but AA increased toxicity relative to Al alone. Low concentration (4 mg L -1 ) AA and HA do not change partitioning but increase uptake; they both detoxify, but AA less than HA. The study shows OC:Al ratio is critical in predicting Al behaviour in natural waters, also uptake is mediated by snail behaviour, not solely a function of concentration and form of Al. Therefore, predicting Al behaviour will be subject to errors in determining relevant water composition and response of biota to the new speciation. However, with respect to toxicity, rather than other aspects of Al behaviour, different ratios of HA and Al are insignificant compared to whether AA is present rather than HA. - Highlights: → Toxicity assessment in which environmental relevance is of primary concern. → Mass balance of Al monitored throughout the exposure period. → Al behaviour influenced by concentration of organic matter. → Strong dependence of toxicity on type rather than concentration of organic matter. → Toxicity is a function of Al behaviour but also animal behaviour.

  19. Effect of natural organic matter on the photo-induced toxicity of titanium dioxide nanoparticles.

    Science.gov (United States)

    Wormington, Alexis M; Coral, Jason; Alloy, Matthew M; Delmarè, Carmen L; Mansfield, Charles M; Klaine, Stephen J; Bisesi, Joseph H; Roberts, Aaron P

    2017-06-01

    Nano-titanium dioxide (TiO 2 ) is the most widely used form of nanoparticles in commercial industry and comes in 2 main configurations: rutile and anatase. Rutile TiO 2 is used in ultraviolet (UV) screening applications, whereas anatase TiO 2 crystals have a surface defect that makes them photoreactive. There are numerous reports in the literature of photo-induced toxicity to aquatic organisms following coexposure to anatase nano-TiO 2 and UV. All natural freshwater contains varying amounts of natural organic matter (NOM), which can drive UV attenuation and quench reactive oxygen species (ROS) in aquatic ecosystems. The present research examined how NOM alters the photo-induced toxicity of anatase nano-TiO 2 . Daphnia magna neonates were coexposed to NOM and photoexcited anatase nano-TiO 2 for 48 h. Natural organic matter concentrations as low as 4 mg/L reduced anatase nano-TiO 2 toxicity by nearly 100%. These concentrations of NOM attenuated UV by <10% in the exposure system. However, ROS production measured using a fluorescence assay was significantly reduced in a NOM concentration--dependent manner. Taken together, these data suggest that NOM reduces anatase nano-TiO 2 toxicity via an ROS quenching mechanism and not by attenuation of UV. Environ Toxicol Chem 2017;36:1661-1666. © 2016 SETAC. © 2016 SETAC.

  20. The Simplest Flowchart Stating the Mechanisms for Organic Xenobiotics-induced Toxicity: Can it Possibly be Accepted as a “Central Dogma” for Toxic Mechanisms?

    Science.gov (United States)

    Lee, Sundong; Cho, Myung-Haing

    2014-01-01

    Xenobiotics causing a variety of toxicity in biological systems could be classified as two types, inorganic and organic chemicals. It is estimated that the organic xenobiotics are responsible for approximately 80~90% of chemical-induced toxicity in human population. In the class for toxicology, we have encountered some difficulties in explaining the mechanisms of toxicity caused especially by organic chemicals. Here, a simple flowchart was introduced for explaining the mechanism of toxicity caused by organic xenobiotics, as the central dogma of molecular biology. This flowchart, referred to as a central dogma, was described based on a view of various aspects as follows: direct-acting chemicals vs. indirect-acting chemicals, cytochrome P450-dependent vs. cytochrome P450-independent biotransformation, reactive intermediates, reactivation, toxicokinetics vs. toxicodynamics, and reversibility vs. irreversibility. Thus, the primary objective of this flowchart is to help better understanding of the organic xenobiotics-induced toxic mechanisms, providing a major pathway for toxicity occurring in biological systems. PMID:25343011

  1. Toxicity of natural mixtures of organic pollutants in temperate and polar marine phytoplankton

    KAUST Repository

    Echeveste, Pedro

    2016-07-26

    Semivolatile and persistent organic pollutants (POPs) undergo atmospheric transport before being deposited to the oceans, where they partition to phytoplankton organic matter. The goal of this study was to determine the toxicity of naturally occurring complex mixtures of organic pollutants to temperate and polar phytoplankton communities from the Mediterranean Sea, the North East (NE) Atlantic, and Southern Oceans. The cell abundance of the different phytoplankton groups, chlorophyll a concentrations, viability of the cells, and growth and decay constants were monitored in response to addition of a range of concentrations of mixtures of organic pollutants obtained from seawater extracts. Almost all of the phytoplankton groups were significantly affected by the complex mixtures of non-polar and polar organic pollutants, with toxicity being greater for these mixtures than for single POPs or simple POP mixtures. Cocktails\\' toxicity arose at concentrations as low as tenfold the field oceanic levels, probably due to a higher chemical activity of the mixture than of simple POPs mixtures. Overall, smaller cells were the most affected, although Mediterranean picophytoplankton was significantly more tolerant to non-polar POPs than picophytoplankton from the Atlantic Ocean or the Bellingshausen Sea microphytoplankton. © 2016 Elsevier B.V.

  2. Metal-organic frameworks for the removal of toxic industrial chemicals and chemical warfare agents.

    Science.gov (United States)

    Bobbitt, N Scott; Mendonca, Matthew L; Howarth, Ashlee J; Islamoglu, Timur; Hupp, Joseph T; Farha, Omar K; Snurr, Randall Q

    2017-06-06

    Owing to the vast diversity of linkers, nodes, and topologies, metal-organic frameworks can be tailored for specific tasks, such as chemical separations or catalysis. Accordingly, these materials have attracted significant interest for capture and/or detoxification of toxic industrial chemicals and chemical warfare agents. In this paper, we review recent experimental and computational work pertaining to the capture of several industrially-relevant toxic chemicals, including NH 3 , SO 2 , NO 2 , H 2 S, and some volatile organic compounds, with particular emphasis on the challenging issue of designing materials that selectively adsorb these chemicals in the presence of water. We also examine recent research on the capture and catalytic degradation of chemical warfare agents such as sarin and sulfur mustard using metal-organic frameworks.

  3. Oral bioaccessibility of semi-volatile organic compounds (SVOCs) in settled dust: A review of measurement methods, data and influencing factors.

    Science.gov (United States)

    Raffy, Gaëlle; Mercier, Fabien; Glorennec, Philippe; Mandin, Corinne; Le Bot, Barbara

    2018-06-15

    Many semi-volatile organic compounds (SVOCs), suspected of reprotoxic, neurotoxic or carcinogenic effects, were measured in indoor settled dust. Dust ingestion is a non-negligible pathway of exposure to some of these SVOCs, and an accurate knowledge of the real exposure is necessary for a better evaluation of health risks. To this end, the bioaccessibility of SVOCs in dust needs to be considered. In the present work, bioaccessibility measurement methods, SVOCs' oral bioaccessibility data and influencing factors were reviewed. SVOC bioaccessibilities (%) ranged from 11 to 94, 8 to 100, 3 to 92, 1 to 81, 6 to 52, and 2 to 17, for brominated flame retardants, organophosphorus flame retardants, polychlorobiphenyls, phthalates, pesticides and polycyclic aromatic hydrocarbons, respectively. Measurements method produced varying results depending on the inclusion of food and/or sink in the model. Characteristics of dust, e.g., organic matter content and particle size, also influenced bioaccessibility data. Last, results were influenced by SVOC properties, such as octanol/water partition coefficient and migration pathway into dust. Factors related to dust and SVOCs could be used in prediction models. To this end, more bioaccessibility studies covering more substances should be performed, using methods that are harmonized and validated by comparison to in-vivo studies. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Severe Toxic Skin Reaction Caused by a Common Anemone and Identification of the Culprit Organism.

    Science.gov (United States)

    Tezcan, Özgür Deniz; Gözer, Özgür

    2015-01-01

    In a marine envenomation, identification of the culprit organism can be difficult. In this case report, we present our method to identify snakelocks anemone (Anemonia viridis or formerly Anemonia sulcata) as the culprit of a severe toxic skin reaction. A. viridis is one of the most common anemones of the Mediterranean Sea and the North Atlantic Ocean. It lives at a depth of up to 10 m. It is a member of the phylum Cnidaria, which includes jellyfish, anemones, hydroids, and corals. They have toxic organelles called cnidocysts that have the capacity to inject venom with microscopic harpoon-like structures. The cnidocysts of A. viridis may cause toxic and allergic reactions, and although its venom is one of the most studied cnidarian venoms, detailed case reports are rare. © 2015 International Society of Travel Medicine.

  5. Review Article. Organochlorine pesticides, their toxic effects on living organisms and their fate in the environment

    Directory of Open Access Journals (Sweden)

    Jayaraj Ravindran

    2016-12-01

    Full Text Available Organochlorine (OC pesticides are synthetic pesticides widely used all over the world. They belong to the group of chlorinated hydrocarbon derivatives, which have vast application in the chemical industry and in agriculture. These compounds are known for their high toxicity, slow degradation and bioaccumulation. Even though many of the compounds which belong to OC were banned in developed countries, the use of these agents has been rising. This concerns particularly abuse of these chemicals which is in practice across the continents. Though pesticides have been developed with the concept of target organism toxicity, often non-target species are affected badly by their application. The purpose of this review is to list the major classes of pesticides, to understand organochlorine pesticides based on their activity and persistence, and also to understand their biochemical toxicity.

  6. Toxicity of Select Organic Acids to the Slightly Thermophilic Acidophile Acidithiobaccillus Caldus

    Energy Technology Data Exchange (ETDEWEB)

    John E Aston; William A Apel; Brady D Lee; Brent M Peyton

    2009-02-01

    Acidithiobacillus caldus is a thermophilic acidophile found in commercial biomining, acid mine drainage systems, and natural environments. Previous work has characterized A. caldus as a chemolithotrophic autotroph capable of utilizing reduced sulfur compounds under aerobic conditions. Organic acids are especially toxic to chemolithotrophs in low-pH environments, where they diffuse more readily into the cell and deprotonate within the cytoplasm. In the present study, the toxic effects of oxaloacetate, pyruvate, 2-ketoglutarate, acetate, malate, succinate, and fumarate on A. caldus strain BC13 were examined under batch conditions. All tested organic acids exhibited some inhibitory effect. Oxaloacetate was observed to inhibit growth completely at a concentration of 250 µM, whereas other organic acids were completely inhibitory at concentrations of between 1,000 and 5,000 µM. In these experiments, the measured concentrations of organic acids decreased with time, indicating uptake or assimilation by the cells. Phospholipid fatty acid analyses indicated an effect of organic acids on the cellular envelope. Notable differences included an increase in cyclic fatty acids in the presence of organic acids, indicating possible instability of the cellular envelope. This was supported by field emission scanning-electron micrographs showing blebbing and sluffing in cells grown in the presence of organic acids.

  7. Examination of Mechanisms Responsible for Organic Dust-related Diseases: Mediator Release induced by Microorgansims. A review

    DEFF Research Database (Denmark)

    Norn, Svend; Clementsen, Paul; Kristensen, K.S.

    1994-01-01

    Farmakologi, org. dust-related diseases, bacteria, pathogenic mechanisms, mediator release, entoxins - fungal spores......Farmakologi, org. dust-related diseases, bacteria, pathogenic mechanisms, mediator release, entoxins - fungal spores...

  8. Comparative toxicity test of water-accommodated fractions of oils and oil dispersants to marine organisms

    International Nuclear Information System (INIS)

    1989-01-01

    This reference method describes a simple procedure for comparing the toxicity of oil, oil dispersants, and mixtures thereof, to marine animals. It allows the toxicity of different dispersants to be rapidly compared to that of oil, or of a mixture of oil an oil dispersant. It is designed for routine monitoring and screening purposes and is not appropriate as a research method. The physical and chemical properties of oil dispersants create many difficulties in the measurements of their toxicity to marine organisms. Strictly speaking, their toxicity can only be accurately estimated using complex procedures and apparatus. (A relatively simple apparatus for preparing oil/water or oil/water/oil dispersant emulsions is described in Appendix B). Simpler methods can provide useful information, provided their limitations are clearly understood and taken into consideration in the assessment and application of their results. Some of the special considerations relating to the measurement of the toxicity of oil and oil dispersants are described in Appendix A. The Appendix also explains the rationale and limitations of the method described here. 3 refs, 4 figs, 2 tabs

  9. Nature and prevalence of non-additive toxic effects in industrially relevant mixtures of organic chemicals.

    Science.gov (United States)

    Parvez, Shahid; Venkataraman, Chandra; Mukherji, Suparna

    2009-06-01

    The concentration addition (CA) and the independent action (IA) models are widely used for predicting mixture toxicity based on its composition and individual component dose-response profiles. However, the prediction based on these models may be inaccurate due to interaction among mixture components. In this work, the nature and prevalence of non-additive effects were explored for binary, ternary and quaternary mixtures composed of hydrophobic organic compounds (HOCs). The toxicity of each individual component and mixture was determined using the Vibrio fischeri bioluminescence inhibition assay. For each combination of chemicals specified by the 2(n) factorial design, the percent deviation of the predicted toxic effect from the measured value was used to characterize mixtures as synergistic (positive deviation) and antagonistic (negative deviation). An arbitrary classification scheme was proposed based on the magnitude of deviation (d) as: additive (50%, class-IV) antagonistic/synergistic. Naphthalene, n-butanol, o-xylene, catechol and p-cresol led to synergism in mixtures while 1, 2, 4-trimethylbenzene and 1, 3-dimethylnaphthalene contributed to antagonism. Most of the mixtures depicted additive or antagonistic effect. Synergism was prominent in some of the mixtures, such as, pulp and paper, textile dyes, and a mixture composed of polynuclear aromatic hydrocarbons. The organic chemical industry mixture depicted the highest abundance of antagonism and least synergism. Mixture toxicity was found to depend on partition coefficient, molecular connectivity index and relative concentration of the components.

  10. Reactive oxygen species formed in aqueous mixtures of secondary organic aerosols and mineral dust influencing cloud chemistry and public health in the Anthropocene.

    Science.gov (United States)

    Tong, Haijie; Lakey, Pascale S J; Arangio, Andrea M; Socorro, Joanna; Kampf, Christopher J; Berkemeier, Thomas; Brune, William H; Pöschl, Ulrich; Shiraiwa, Manabu

    2017-08-24

    Mineral dust and secondary organic aerosols (SOA) account for a major fraction of atmospheric particulate matter, affecting climate, air quality and public health. How mineral dust interacts with SOA to influence cloud chemistry and public health, however, is not well understood. Here, we investigated the formation of reactive oxygen species (ROS), which are key species of atmospheric and physiological chemistry, in aqueous mixtures of SOA and mineral dust by applying electron paramagnetic resonance (EPR) spectrometry in combination with a spin-trapping technique, liquid chromatography-tandem mass spectrometry (LC-MS/MS), and a kinetic model. We found that substantial amounts of ROS including OH, superoxide as well as carbon- and oxygen-centred organic radicals can be formed in aqueous mixtures of isoprene, α-pinene, naphthalene SOA and various kinds of mineral dust (ripidolite, montmorillonite, kaolinite, palygorskite, and Saharan dust). The molar yields of total radicals were ∼0.02-0.5% at 295 K, which showed higher values at 310 K, upon 254 nm UV exposure, and under low pH (formation can be explained by the decomposition of organic hydroperoxides, which are a prominent fraction of SOA, through interactions with water and Fenton-like reactions with dissolved transition metal ions. Our findings imply that the chemical reactivity and aging of SOA particles can be enhanced upon interaction with mineral dust in deliquesced particles or cloud/fog droplets. SOA decomposition could be comparably important to the classical Fenton reaction of H 2 O 2 with Fe 2+ and that SOA can be the main source of OH radicals in aqueous droplets at low concentrations of H 2 O 2 and Fe 2+ . In the human respiratory tract, the inhalation and deposition of SOA and mineral dust can also lead to the release of ROS, which may contribute to oxidative stress and play an important role in the adverse health effects of atmospheric aerosols in the Anthropocene.

  11. Gold leaching by organic base polythionates: new non-toxic and secure technology.

    Science.gov (United States)

    Smolyaninov, Vladislav; Shekhvatova, Galina; Vainshtein, Mikhail

    2014-01-01

    The article present a review on own experimental and some published data which are related with the gold leaching. It is well-known that the most common and usual process of the leaching with cyanide can be dangerous, needs a great water consumption, and additional costs for remediation of the poisoned and toxic sites. The experimental data described production of poythionates which are not toxic but perspective for the prosperous gold leaching. The paper dedicated to the safe gold leaching with thiosulfates and organic salts of polythionic acids (organic base polythionates). The method of production of these polythionates based on the Smolyaninov reaction is described in stages and in details for the first time. Possible application of the polythionates application in the gold leaching is discussed and its advantages are compared with the gold leaching by cyanation.

  12. Nanomaterial translocation - the biokinetics, tissue accumulation, toxicity and fate of materials in secondary organs

    DEFF Research Database (Denmark)

    Kermanizadeh, Ali; Balharry, Dominique; Wallin, Håkan

    2015-01-01

    into the toxicity posed by the NMs in these secondary organs is expanding due to the realisation that some materials may reach and accumulate in these target sites. The translocation to secondary organs includes, but is not limited to, the hepatic, central nervous, cardiovascular and renal systems. Current data...... dioxide and quantum dots) or fast (e.g. zinc oxide) solubility. The translocation of NMs following intratracheal, intranasal and pharyngeal aspiration is higher (up to 10% of administered dose), however the relevance of these routes for risk assessment is questionable. Uptake of the materials from....... For toxicological and risk evaluation, further information on the toxicokinetics and persistence of NMs is crucial. The overall aim of this review is to outline the data currently available in the literature on the biokinetics, accumulation, toxicity and eventual fate of NMs in order to assess the potential risks...

  13. Arabidopsis and the Genetic Potential for the Phytoremediation of Toxic Elemental and Organic Pollutants

    OpenAIRE

    Cobbett, Christopher S.; Meagher, Richard B.

    2002-01-01

    In a process called phytoremediation, plants can be used to extract, detoxify, and/or sequester toxic pollutants from soil, water, and air. Phytoremediation may become an essential tool in cleaning the environment and reducing human and animal exposure to potential carcinogens and other toxins. Arabidopsis has provided useful information about the genetic, physiological, and biochemical mechanisms behind phytoremediation, and it is an excellent model genetic organism to test foreign gene expr...

  14. Chronic toxicity of the organic reactor coolant OS-84 to an aquatic organism

    International Nuclear Information System (INIS)

    Guthrie, J.E.; Wiewel, A.M.

    1977-04-01

    The toxicity of irradiated partially hydrogenated polyphenyls to successive generations of Aedes aegypti (Linnaeus) is reported. Suspensions prepared in the laboratory exceeding 0.75 mg/l of the coolant in water significantly affected the survival of the larvae and the percentage of larvae that pupated. No effects on adult emergence, number of eggs laid per female or on the hatching success of these eggs were observed in concentrations ranging from 0.5 to 2 mg/l. Few of the larvae reared in a concentration of 5 mg/l survived beyond the second instar stage and none of them pupated. (author)

  15. Sensing and capture of toxic and hazardous gases and vapors by metal-organic frameworks.

    Science.gov (United States)

    Wang, Hao; Lustig, William P; Li, Jing

    2018-03-13

    Toxic and hazardous chemical species are ubiquitous, predominantly emitted by anthropogenic activities, and pose serious risks to human health and the environment. Thus, the sensing and subsequent capture of these chemicals, especially in the gas or vapor phase, are of extreme importance. To this end, metal-organic frameworks have attracted significant interest, as their high porosity and wide tunability make them ideal for both applications. These tailorable framework materials are particularly promising for the specific sensing and capture of targeted chemicals, as they can be designed to fit a diverse range of required conditions. This review will discuss the advantages of metal-organic frameworks in the sensing and capture of harmful gases and vapors, as well as principles and strategies guiding the design of these materials. Recent progress in the luminescent detection of aromatic and aliphatic volatile organic compounds, toxic gases, and chemical warfare agents will be summarized, and the adsorptive removal of fluorocarbons/chlorofluorocarbons, volatile radioactive species, toxic industrial gases and chemical warfare agents will be discussed.

  16. Modeling time-dependent toxicity to aquatic organisms from pulsed exposure of PAHs in urban road runoff

    International Nuclear Information System (INIS)

    Zhang Wei; Ye Youbin; Tong Yindong; Ou Langbo; Hu Dan; Wang Xuejun

    2011-01-01

    Understanding of the magnitude of urban runoff toxicity to aquatic organisms is important for effective management of runoff quality. In this paper, the aquatic toxicity of polycyclic aromatic hydrocarbons (PAHs) in urban road runoff was evaluated through a damage assessment model. Mortality probability of the organisms representative in aquatic environment was calculated using the monitored PAHs concentration in road runoff. The result showed that the toxicity of runoff in spring was higher than those in summer. Analysis of the time-dependent toxicity of series of runoff water samples illustrated that the toxicity of runoff water in the final phase of a runoff event may be as high as those in the initial phase. Therefore, the storm runoff treatment systems or strategies designed for capture and treatment of the initial portion of runoff may be inappropriate for control of runoff toxicity. - Research highlights: → Toxicity resulting from realistic exposure patterns of urban runoff is evaluated. → Toxicity of runoff water in the final phase is as high as the initial phase. → Treatment of the initial runoff portion is inappropriate to abate runoff toxicity. - Toxicity to aquatic organisms after sequential pulsed exposure to PAHs in urban road runoff is evaluated.

  17. Elucidating mechanisms of toxic action of dissolved organic chemicals in oil sands process-affected water (OSPW).

    Science.gov (United States)

    Morandi, Garrett D; Wiseman, Steve B; Guan, Miao; Zhang, Xiaowei W; Martin, Jonathan W; Giesy, John P

    2017-11-01

    Oil sands process-affected water (OSPW) is generated during extraction of bitumen in the surface-mining oil sands industry in Alberta, Canada, and is acutely and chronically toxic to aquatic organisms. It is known that dissolved organic compounds in OSPW are responsible for most toxic effects, but knowledge of the specific mechanism(s) of toxicity, is limited. Using bioassay-based effects-directed analysis, the dissolved organic fraction of OSPW has previously been fractionated, ultimately producing refined samples of dissolved organic chemicals in OSPW, each with distinct chemical profiles. Using the Escherichia coli K-12 strain MG1655 gene reporter live cell array, the present study investigated relationships between toxic potencies of each fraction, expression of genes and characterization of chemicals in each of five acutely toxic and one non-toxic extract of OSPW derived by use of effects-directed analysis. Effects on expressions of genes related to response to oxidative stress, protein stress and DNA damage were indicative of exposure to acutely toxic extracts of OSPW. Additionally, six genes were uniquely responsive to acutely toxic extracts of OSPW. Evidence presented supports a role for sulphur- and nitrogen-containing chemical classes in the toxicity of extracts of OSPW. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Arabidopsis and the Genetic Potential for the Phytoremediation of Toxic Elemental and Organic Pollutants

    Science.gov (United States)

    Cobbett, Christopher S.; Meagher, Richard B.

    2002-01-01

    In a process called phytoremediation, plants can be used to extract, detoxify, and/or sequester toxic pollutants from soil, water, and air. Phytoremediation may become an essential tool in cleaning the environment and reducing human and animal exposure to potential carcinogens and other toxins. Arabidopsis has provided useful information about the genetic, physiological, and biochemical mechanisms behind phytoremediation, and it is an excellent model genetic organism to test foreign gene expression. This review focuses on Arabidopsis studies concerning: 1) the remediation of elemental pollutants; 2) the remediation of organic pollutants; and 3) the phytoremediation genome. Elemental pollutants include heavy metals and metalloids (e.g., mercury, lead, cadmium, arsenic) that are immutable. The general goal of phytoremediation is to extract, detoxify, and hyperaccumulate elemental pollutants in above-ground plant tissues for later harvest. A few dozen Arabidopsis genes and proteins that play direct roles in the remediation of elemental pollutants are discussed. Organic pollutants include toxic chemicals such as benzene, benzo(a)pyrene, polychlorinated biphenyls, trichloroethylene, trinitrotoluene, and dichlorodiphenyltrichloroethane. Phytoremediation of organic pollutants is focused on their complete mineralization to harmless products, however, less is known about the potential of plants to act on complex organic chemicals. A preliminary survey of the Arabidopsis genome suggests that as many as 700 genes encode proteins that have the capacity to act directly on environmental pollutants or could be modified to do so. The potential of the phytoremediation proteome to be used to reduce human exposure to toxic pollutants appears to be enormous and untapped. PMID:22303204

  19. Performance investigation of low-toxic organic corrosion inhibitors in amine treating unit

    International Nuclear Information System (INIS)

    Veawab, A.; Tanthapanichakoon, W.

    2003-01-01

    Amine treating unit is constantly subject to severe corrosion problems leading to extra expenditure and operational limitations. Heavy-metal vanadium compounds are extensively used as corrosion inhibitors to suppress the severe corrosion to an acceptable level. In recent years, the fact that these vanadium compounds are inherently toxic and can potentially pose adverse impacts on the human health and the environment has brought about environmental awareness that causes their uses costly due to the difficulty in waste disposal. To respond to the environmental concern and reduce cost of waste disposal as well as prepare for more stringent regulations for chemical uses, the development of low-toxic corrosion inhibitors is necessary. This work therefore focuses on an investigation of inhibition performance of a number of organic and inorganic compounds that have relatively low toxicity in comparison with conventional inhibitors. The performance evaluation was carried out through corrosion experiments using carbon steel specimens. The experiments were done in 3 and 5 kmol/m 3 monoethanolamine (MEA) solution saturated with CO 2 at 80 o C. It was found that several tested compounds have potential to be effective low-toxic corrosion inhibitors. The promising compounds provide reasonable and in some cases comparable protection performance to the conventional inhibitor. (author)

  20. Acute toxicity assessment of Osthol content in bio-pesticides using two aquatic organisms

    Directory of Open Access Journals (Sweden)

    Eun-Chae Yim

    2014-12-01

    Full Text Available Objectives This study focused on the assessment of acute toxicity caused by Osthol, a major component of environment-friendly biological pesticides, by using two aquatic organisms. Methods The assessment of acute toxicity caused by Osthol was conducted in Daphnia magna and by examining the morphological abnormalities in Danio rerio embryos. Results The median effective concentration value of Osthol in D. magna 48 hours after inoculation was 19.3 μM. The median lethal concentration of D. rerio embryo at 96 hours was 30.6 μM. No observed effect concentration and predicted no effect concentration values of Osthol in D. magna and D. rerio were calculated as 5.4 and 0.19 μM, respectively. There was an increase in the morphological abnormalities in D. rerio embryo due to Osthol over time. Coagulation, delayed hatching, yolk sac edema, pericardial edema, and pigmentation were observed in embryos at 24–48 hours. Symptoms of scoliosis and head edema occurred after 72 hours. In addition, bent tails, ocular defects, and symptoms of collapse were observed in fertilized embryo tissue within 96 hours. Ocular defects and pigmentation were the additional symptoms observed in this study. Conclusions Because Osthol showed considerable toxicity levels continuous toxicity evaluation in agro-ecosystems is necessary when bio-pesticides containing Osthol are used.

  1. Influences of natural emission sources (wildfires and Saharan dust) on the urban organic aerosol in Barcelona (Western Mediterranean Basis) during a PM event.

    Science.gov (United States)

    van Drooge, Barend L; Lopez, Jordi F; Grimalt, Joan O

    2012-11-01

    The urban air quality in Barcelona in the Western Mediterranean Basin is characterized by overall high particulate matter (PM) concentrations, due to intensive local anthropogenic emissions and specific meteorological conditions. Moreover, on several days, especially in summer, natural PM sources, such as long-range transported Saharan dust from Northern Africa or wildfires on the Iberian Peninsula and around the Mediterranean Basin, may influence the levels and composition of the organic aerosol. In the second half of July 2009, daily collected PM(10) filter samples in an urban background site in Barcelona were analyzed on organic tracer compounds representing several emission sources. During this period, an important PM peak event was observed. Individual organic compound concentrations increased two to five times during this event. Although highest increase was observed for the organic tracer of biomass burning, the contribution to the organic aerosol was estimated to be around 6 %. Organic tracers that could be related to Saharan dust showed no correlation with the PM and OC levels, while this was the case for those related to fossil fuel combustion from traffic emissions. Moreover, a change in the meteorological conditions gave way to an overall increase of the urban background contamination. Long-range atmospheric transport of organic compounds from primary emissions sources (i.e., wildfires and Saharan dust) has a relatively moderate impact on the organic aerosol in an urban area where the local emissions are dominating.

  2. Review of reproductive and developmental toxicity induced by organotins in aquatic organisms and experimental animals

    Energy Technology Data Exchange (ETDEWEB)

    Hirose, A.; Takagi, A.; Nishimura, T.; Kanno, J.; Ema, M. [National Inst. of Health Sciences, Tokyo (Japan)

    2004-09-15

    Widespread use of organotins has caused increasing amounts to be released into the environment. The most important non-pesticidal route of entry of organotins into the environment is through leaching of organotin-stabilized PVC in water, and the use in antifouling agents, resulting in the introduction of organotin into the aquatic environment. Data are available regarding the detection of butyltins and phenyltins in aquatic marine organisms and marine products. Food chain bioamplification of butyltin in oysters, mud crabs, marine mussels, chinook salmons, dolphins, tunas, and sharks and of phenyltin in carps and horseshoe crabs has been reported. These findings indicate that organotins accumulate in the food chain and are bioconcentrated, and that humans can be exposed to organotins via seafood. The levels of organotin compounds in seafood are not considered to be sufficiently high to affect human health. However, Belfroid et al. (2000) noted that more research on residual TBT levels in seafood was needed before a definitive conclusion on possible health risks could be drawn. Although the toxicity of organotins has been extensively reviewed, the reproductive and developmental toxicity of organotins is not well understood. We summarized the data of the studies on reproductive and developmental toxicity of organotins in aquatic organisms and experimental animals.

  3. USING STRUCTURAL EFFECTS ON THE ORGANIZATION OF THE CYTOSKELETON OF RAINBOW TROUT HEPATOCYTES TO SORT PATHWAYS OF REACTIVE TOXICITY

    Science.gov (United States)

    Quinones have been shown to be more acutely toxic to aquatic organisms than chemicals that are not capable of either direct interaction with cellular nucleophiles or potentially metabolized free radicals. For the development of accurate QSAR models, in vitro toxicity assays are n...

  4. Phototransformation of Amlodipine in Aqueous Solution: Toxicity of the Drug and Its Photoproduct on Aquatic Organisms

    Directory of Open Access Journals (Sweden)

    Marina DellaGreca

    2007-01-01

    Full Text Available The phototransformation of amlodipine in water was investigated under various conditions. A quantum yield ΦS2.2×10−4 and a half-life time t1/2 0.419 days were calculated when the drug in water (10−4 M was exposed to sunlight. The only photoproduct found was its pyridine derivative. Formation of this product was explained on the basis of a radical cation intermediate. The acute and chronic toxicity of the drug and its photoproduct were evaluated on different organisms of the freshwater chain (Brachionus calyciflorus, Thamnocephalus platyurus, Daphnia magna, Ceriodaphnia dubia. The photoproduct exhibited a stronger toxic potential than the parent drug on the long time for C. dubia.

  5. The effect of pH on the bioconcentration and toxicity of weak organic electrolytes

    DEFF Research Database (Denmark)

    Rendal, Cecilie

    to the bioconcentration of ionizing organic compounds showed that this fraction cannot safely be overlooked. The work presented in this thesis suggests that the standard test procedures used to test toxicity and bioconcentration are not sufficient to fully illuminate the ecotoxicity of ionizing organic compounds unless......Many of the compounds in use today have ionizing properties. Investigations have shown that around half of the compounds preregistered for REACH and over 70% of all pharmaceuticals are ionizing organic compounds. These compounds may pose a risk when they are released into the environment....... Ionization, however, complicates the environmental risk assessment of these compounds because the uptake processes of the neutral fraction differ from the processes of the ionized fraction. Acids are increasingly neutral at pH levels below the pKa while bases are increasingly neutral at pH levels above the p...

  6. Agglomeration processes sustained by dust density waves in Ar/C2H2 plasma: From C2H2 injection to the formation of an organized structure

    International Nuclear Information System (INIS)

    Dap, Simon; Hugon, Robert; Poucques, Ludovic de; Briancon, Jean-Luc; Bougdira, Jamal; Lacroix, David

    2013-01-01

    In this paper, an experimental investigation of dust particle agglomeration in a capacitively coupled RF discharge is reported. Carbonaceous particles are produced in an argon plasma using acetylene. As soon as the particle density becomes sufficient, dust density waves (DDWs) are spontaneously excited within the cathode sheath. Recently, it was proven that DDWs can significantly enhance the agglomeration rate between particles by transferring them a significant kinetic energy. Thus, it helps them to overcome Coulomb repulsion. The influence of this mechanism is studied from acetylene injection to the formation of very large agglomerates forming an organized structure after a few dozens of seconds. For this purpose, three diagnostic tools are used: extinction measurements to probe nanometer-sized particles, fast imaging for large agglomerates and a dust extraction technique developed for ex-situ analysis.

  7. Hazard identification of contaminated sites. Ranking potential toxicity of organic sediment extracts in crustacean and fish

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, J.; Sundberg, H.; Aakerman, G.; Grunder, K.; Eklund, B.; Breitholtz, M. [Dept. of Applied Environmental Science (ITM), Stockholm Univ. (Sweden)

    2008-09-15

    Background, aim, and scope: It is well known that contaminated sediments represent a potential long-term source of pollutants to the aquatic environment. To protect human and ecosystem health, it is becoming common to remediate contaminated sites. However, the great cost associated with, e.g., dredging in combination with the large numbers of contaminated sites makes it crucial to pinpoint those sites that are in greatest need of remediation. In most European countries, this prioritization process has almost exclusively been based on chemical analyses of known substances; only seldom toxicity data has been considered. The main objective of the current study was therefore to develop a tool for hazard identification of sediment by ranking potential toxicity of organic sediment extracts in a crustacean and a fish. A secondary objective was to investigate the difference in potential toxicity between compounds with different polarities. Materials and methods Early life stages of the crustacean Nitocra spinipes and the fish Oncorhynchus mykiss, which represent organisms from different trophic levels (primary and secondary consumer) and with different routes of exposure (i.e. ingestion through food, diffusive uptake, and maternal transfer), were exposed to hexane and acetone fractions (semi-polar compounds) of sediment from five locations, ranging from heavily to low contaminated. Preliminary tests showed that the extracts were non-bioavailable to the crustacean when exposed via water, and the extracts were therefore loaded on silica gel. Rainbow trout embryos were exposed using nano-injection technique. Results and discussion Clear concentration-response relationships of both mortality and larval development were observed in all tests with N. spinipes. Also for rainbow trout, the observed effects (e.g., abnormality, hemorrhage, asymmetric yolk sac) followed a dose-related pattern. Interestingly, our results indicate that some of the locations contained toxic semi

  8. Sub-chronic toxicity of low concentrations of industrial volatile organic pollutants in vitro

    International Nuclear Information System (INIS)

    McDermott, Catherine; Allshire, Ashley; Pelt, Frank N.A.M. van; Heffron, James J.A.

    2007-01-01

    Organic solvents form an important class of pollutants in the ambient air and have been associated with neurotoxicity and immunotoxicity in humans. Here we investigated the biological effects of sub-chronic exposure to industrially important volatile organic solvents in vitro. Jurkat T cells were exposed to toluene, n-hexane and methyl ethyl ketone (MEK) individually for 5 days and solvent exposure levels were confirmed by headspace gas chromatography. A neuroblastoma cell line (SH-SY5Y) was exposed to toluene for the same period. Following exposure, cells were harvested and toxicity measured in terms of the following endpoints: membrane damage (LDH leakage), perturbations in intracellular free Ca 2+ , changes in glutathione redox status and dual-phosphorylation of MAP kinases ERK1/2, JNK and p38. The results show that sub-chronic exposure to the volatile organic solvents causes membrane damage, increased intracellular free calcium and altered glutathione redox status in both cell lines. However, acute and sub-chronic solvent exposure did not result in MAP kinase phosphorylation. Toxicity of the solvents tested increased with hydrophobicity. The lowest-observed-adverse-effect-levels (LOAELs) measured in vitro were close to blood solvent concentrations reported for individuals exposed to the agents at levels at or below their individual threshold limit values (TLVs)

  9. Black Carbon, Dust and Organic Matter at South Cascade Glacier in Washington State, USA: A Comprehensive Characterization of Temporal (1865-2014) and Spatial Variability

    Science.gov (United States)

    Kaspari, S.; Pittenger, D.; Swick, M.; Skiles, M.; Perez, A.; Sethi, H.; Sevier, E.

    2017-12-01

    Rising temperatures are a widely recognized cause of glacial retreat in Washington, however light absorbing aerosols (LAA, including black carbon (BC), dust and organic matter) can also contribute to increased melt by reducing snow albedo. We present updated results of BC and dust variability at South Cascade (SOCAS) glacier spanning 1865-1994 using a 158 m ice core. Peak BC deposition occurred between 1940-1958, when median BC concentrations were 25 times higher than background levels. Post 1958 BC concentrations decrease, followed by an increase post 1980 associated with melt consolidation and/or trans-Pacific aerosol transport. Dust deposition at SOCAS is dominated by local sources. Albedo reductions from LAA are dominated by dust deposition, except during high BC deposition events from wildfires, and during the 1940-1958 period when BC contributes equally to albedo reductions. Results from a 2014 field campaign that included collection of 3 shallow ice cores, surface snow, and snow albedo measurements allow the 1865-1994 ice core record to be extended toward present, and spatial variability in LAA to be characterized. Snow albedo transects were measured using a spectrometer. BC concentrations were measured using a Single Particle Soot Photometer (SP2). Gravimetric filtration was used to determine the total LAA, and a thermal gravimetric technique was used to partition the LAA between dust and organic matter. The organic matter was partitioned into organic and elemental carbon using a thermal optical method. These methods allow LAA abundances be measured, but to partition the contribution of the LAA to albedo reductions requires characterization of LAA optical properties. This was accomplished using a Hyperspectral Imaging Microscope Spectrometer method that allows particle reflectance to be measured at 138 nm2 pixel resolution. By combining these methods, we provide a comprehensive characterization of spatial and temporal LAA variability at SOCAS.

  10. Effects of soil organic matter content on cadmium toxicity in Eisenia fetida: implications for the use of biomarkers and standard toxicity tests.

    Science.gov (United States)

    Irizar, A; Rodríguez, M P; Izquierdo, A; Cancio, I; Marigómez, I; Soto, M

    2015-01-01

    Bioavailability is affected by soil physicochemical characteristics such as pH and organic matter (OM) content. In addition, OM constitutes the energy source of Eisenia fetida, a well established model species for soil toxicity assessment. The present work aimed at assessing the effects of changes in OM content on the toxicity of Cd in E. fetida through the measurement of neutral red uptake (NRU) and mortality, growth, and reproduction (Organisation for Economic Co-operation and Development [OECD] Nos. 207 and 222). Complementarily, metallothionein (MT) and catalase transcription levels were measured. To decrease variability inherent to natural soils, artificial soils (Organization for Economic Cooperation and Development 1984) with different OM content (6, 10, and 14%) and spiked with Cd solutions at increasing concentrations were used. Low OM in soil decreased soil ingestion and Cd bioaccumulation but also increased Cd toxicity causing lower NRU of coelomocytes, 100 % mortality, and stronger reproduction impairment, probably due to the lack of energy to maintain protection mechanisms (production of MT).Cd bioaccumulation did not reflect toxicity, and OM played a pivotal role in Cd toxicity. Thus, OM content should be taken into account when using E. fetida in in vivo exposures for soil health assessment.

  11. Treatment of Acute Tacrolimus Toxicity with Phenytoin in Solid Organ Transplant Recipients

    Directory of Open Access Journals (Sweden)

    Arin S. Jantz

    2013-01-01

    Full Text Available The pharmacokinetics of tacrolimus are influenced by many factors, including genetic variability, acute infections, liver dysfunction, and interacting medications, which can result in elevated concentrations. The most appropriate management of acute tacrolimus toxicity has not been defined though case reports exist describing the therapeutic use of enzyme inducers to increase tacrolimus metabolism and decrease concentrations. We are reporting on the utilization of phenytoin to assist in decreasing tacrolimus concentrations in a case series of four solid organ transplant recipients with acute, symptomatic tacrolimus toxicity presenting with elevated serum creatinine, potassium, and tacrolimus trough concentrations greater than 30 ng/mL. All four patients had the potential causative agents stopped or temporarily held and were given 300 to 400 mg/day of phenytoin for two to three days. Within three days of beginning phenytoin, all four patients had a decrease in tacrolimus concentration to less than 15 ng/mL, a return to or near baseline creatinine concentration, and lack of phenytoin-related side effects. Therefore, phenytoin appears to be a safe and potentially beneficial treatment option in patients with symptomatic tacrolimus toxicity.

  12. Quick, portable toxicity testing of marine or terrigenous fluids, sediments, or chemicals with bioluminescent organism

    International Nuclear Information System (INIS)

    Sabate, R.W.; Stiffey, A.V.; Dewailly, E.L.

    1995-01-01

    A hand-held, battery-operated instrument, which measures bioluminescence inhibition of the microscopic marine dinoflagellate Pyrocystis lunula, is capable of field-testing substances for toxicity. The organism is sensitive to ppb of strong toxicants. It tolerates some solvents in concentrations necessary for testing lipophylic samples. A test consumes only micrograms of sample. This method requires no adjustments for salinity, pH, color, or turbidity. It has been used successfully to test oil-well drilling fluids, brines produced with oil, waters and sediments from streams and lakes and petroleum-plant effluents containing contaminants such as benzene. The test is non-specific; however, if the substance is known, the end-point effects a direct measurement of its concentration. One-hour toxicity screening tests in the field produce results comparable to the standard four-hour laboratory test. Keeping the sample in the dark during incubation and testing, together with shortness of the overall procedure, eliminates anomalies from light-sensitive substances. Day-to-day variation, as well as among test replicates, is less than 10%. This quick method yields results comparable with a quick test that uses Photobacterium phosphoria, and with 96-hour tests that use Mysidopsis bahia, Artemia salina, Gonyaulax polyedra, Pimephales promelas, Ceriodaphnia dubia, and Cyprinodon variegatus

  13. Influence of salinity and dissolved organic carbon on acute Cu toxicity to the rotifer Brachionus plicatilis.

    Science.gov (United States)

    Cooper, Christopher A; Tait, Tara; Gray, Holly; Cimprich, Giselle; Santore, Robert C; McGeer, James C; Wood, Christopher M; Smith, D Scott

    2014-01-21

    Acute copper (Cu) toxicity tests (48-h LC50) using the euryhaline rotifer Brachionus plicatilis were performed to assess the effects of salinity (3, 16, 30 ppt) and dissolved organic carbon (DOC, ∼ 1.1, ∼ 3.1, ∼ 4.9, ∼ 13.6 mg C L(-1)) on Cu bioavailability. Total Cu was measured using anodic stripping voltammetry, and free Cu(2+) was measured using ion-selective electrodes. There was a protective effect of salinity observed in all but the highest DOC concentrations; at all other DOC concentrations the LC50 value was significantly higher at 30 ppt than at 3 ppt. At all salinities, DOC complexation significantly reduced Cu toxicity. At higher concentrations of DOC the protective effect increased, but the increase was less than expected from a linear extrapolation of the trend observed at lower concentrations, and the deviation from linearity was greatest at the highest salinity. Light-scattering data indicated that salt induced colloid formation of DOC could be occurring under these conditions, thereby decreasing the number of available reactive sites to complex Cu. When measurements of free Cu across DOC concentrations at each individual salinity were compared, values were very similar, even though the total Cu LC50 values and DOC concentrations varied considerably. Furthermore, measured free Cu values and predicted model values were comparable, highlighting the important link between the concentration of bioavailable free Cu and Cu toxicity.

  14. Toxicity of pentachlorophenol to aquatic organisms under naturally varying and controlled environmental conditions

    Energy Technology Data Exchange (ETDEWEB)

    Hedtke, S.F.; West, C.W.; Allen, K.N.; Norberg-King, T.J.; Mount, D.I.

    1986-06-01

    The toxicity of pentachlorophenol (PCP) was determined in the laboratory for 11 aquatic species. Tests were conducted seasonally in ambient Mississippi River water and under controlled conditions in Lake Superior water. Fifty-one acute toxicity tests were conducted, with LC50 values ranging from 85 micrograms/L for the white sucker Catastomus commersoni during the summer to greater than 7770 micrograms/L for the isopod Asellus racovitzai during the winter. The effect of PCP on growth and/or reproduction was determined for seven species. The most sensitive chronically exposed organisms were the cladoceran Ceriodaphnia reticulata and the snail Physa gyrina. The greatest variation in toxicity was due to species sensitivity. Within a given, season there was as much as a 40-fold difference in LC50 values between species. For any one species, the maximum variation in LC50 between seasons was approximately 14-fold. There were also substantial differences in acute-chronic relationships, with acute/chronic ratios ranging from greater than 37 for C. reticulata to 1 for Simocephalus vetulus. It is suggested that the composition of the aquatic community should be the most important consideration in estimating the potential environmental effects of PCP.

  15. Cyanotoxins: producing organisms, occurrence, toxicity, mechanism of action and human health toxicological risk evaluation.

    Science.gov (United States)

    Buratti, Franca M; Manganelli, Maura; Vichi, Susanna; Stefanelli, Mara; Scardala, Simona; Testai, Emanuela; Funari, Enzo

    2017-03-01

    Cyanobacteria were present on the earth 3.5 billion years ago; since then they have colonized almost all terrestrial and aquatic ecosystems. They produce a high number of bioactive molecules, among which some are cyanotoxins. Cyanobacterial growth at high densities, forming blooms, is increasing in extension and frequency, following anthropogenic activities and climate changes, giving rise to some concern for human health and animal life exposed to cyanotoxins. Numerous cases of lethal poisonings have been associated with cyanotoxins ingestion in wild animal and livestock. In humans few episodes of lethal or severe human poisonings have been recorded after acute or short-term exposure, but the repeated/chronic exposure to low cyanotoxin levels remains a critical issue. The properties of the most frequently detected cyanotoxins (namely, microcystins, nodularins, cylindrospermopsin and neurotoxins) are here critically reviewed, describing for each toxin the available information on producing organisms, biosynthesis/genetic and occurrence, with a focus on the toxicological profile (including kinetics, acute systemic toxicity, mechanism and mode of action, local effects, repeated toxicity, genotoxicity, carcinogenicity, reproductive toxicity; human health effects and epidemiological studies; animal poisoning) with the derivation of health-based values and considerations on the risks for human health.

  16. Zinc oxide nanoparticle toxicity in embryonic zebrafish: Mitigation with different natural organic matter.

    Science.gov (United States)

    Kteeba, Shimaa M; El-Adawi, Hala I; El-Rayis, Osman A; El-Ghobashy, Ahmed E; Schuld, Jessica L; Svoboda, Kurt R; Guo, Laodong

    2017-11-01

    Exposure experiments were conducted to evaluate the influence of dissolved organic matter (DOM) on the toxicity of ZnO-NPs (10-30 nm) and dissolved Zn at sub-lethal doses (50 and 5 ppm, respectively) to zebrafish (Danio rerio). Humic acid, alginic acid, bovine serum albumin and various natural DOM isolated from rivers as the Milwaukee River-WI (NOMW), Yukon River-AK (NOMA) and Suwannee River-GA DOM (NOMS) were used to represent humic substances (HA), carbohydrates (CHO), proteins (PTN), and natural organic matter (NOM), respectively. Initial experiments were carried out to confirm the toxic effect of ZnO-NPs at 50 ppm, followed by mitigation experiments with different types and concentrations of DOM (0.4-40 mg-C/L). Compared to 0% hatch of 50 ppm ZnO-NPs exposed embryos at 72 h post fertilization (hpf), NOMS, NOMW and HA had the best mitigative effects on hatching (53-65%), followed by NOMA, CHO and PTN (19-35%); demonstrating that the mitigation effects on ZnO-NPs toxicity were related to DOM's quantity and composition. At 96 hpf, 20% of embryos exposed to 50 ppm ZnO-NPs hatched, 100% of embryos reared in embryo medium hatched, and close to 100% of the embryos hatched upon mitigation, except for those mitigated with PTN which had less effect. Dissolved Zn (5 ppm) also exhibited the same toxicity on embryos as ZnO-NPs (50 ppm). However, in the presence of HA, NOM and CHO, the hatching rates at 72 and 96 hpf increased significantly compared to 5% hatch without DOM. The overall mitigation effects produced by DOM followed the order of HA ≥ NOMS > NOM (A&W) > CHO > PTN, although specific mitigation effects varied with DOM concentration and functionalities. Our results also indicate that the toxicity of ZnO-NPs to embryos was mostly derived from NPs although dissolved Zn released from ZnO-NPs also interacted with embryos, affecting hatching, but to a less extent. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Toxicity of two imidazolium ionic liquids, [bmim][BF4] and [omim][BF4], to standard aquatic test organisms: Role of acetone in the induced toxicity.

    Science.gov (United States)

    Tsarpali, Vasiliki; Dailianis, Stefanos

    2015-07-01

    The main goal of this study was to investigate the toxicity of the imidazolium-based ionic liquids (ILs), [bmim][BF4] (1-butyl-3-methylimidazolium tetrafluoroborate) and [omim][BF4] (1-octyl-3-methylimidazolium tetrafluoroborate), in battery of standard aquatic toxicity test organisms. Specifically, exposure of the algae Scenedesmus rubescens, crustaceans Thamnocephalus platyurus and Artemia franciscana, rotifers Brachionus calyciflorus and Brachionus plicatilis and bivalve Mytilus galloprovincialis to different concentrations of [bmim][BF4], [omim][BF4] and/or a binary mixture of [bmim][BF4]-[omim][BF4] (1:1) with or without acetone (carrier solvent), revealed that solvent can differentially mediate ILs' toxic profile. Acetone's ability to differentially affect ILs' cation's alkyl chain length, as well as the hydrolysis of [BF4(-)] anions was evident. Given that the toxic potency of the tested ILs seemed to be equal or even higher (in some cases) than those of conventional organic solvents, the present study revealed that the characterization of imidazolium-based ILs as "green solvents" should not be generalized, at least in case of their natural occurrence in mixtures with organic solvents, such as acetone. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Uptake of dissolved inorganic and organic nitrogen by the benthic toxic dinoflagellate Ostreopsis cf. ovata.

    Science.gov (United States)

    Jauzein, Cécile; Couet, Douglas; Blasco, Thierry; Lemée, Rodolphe

    2017-05-01

    Environmental factors that shape dynamics of benthic toxic blooms are largely unknown. In particular, for the toxic dinoflagellate Ostreopsis cf. ovata, the importance of the availability of nutrients and the contribution of the inorganic and organic pools to growth need to be quantified in marine coastal environments. The present study aimed at characterizing N-uptake of dissolved inorganic and organic sources by O. cf. ovata cells, using the 15 N-labelling technique. Experiments were conducted taking into account potential interactions between nutrient uptake systems as well as variations with the diel cycle. Uptake abilities of O. cf. ovata were parameterized for ammonium (NH 4 + ), nitrate (NO 3 - ) and N-urea, from the estimation of kinetic and inhibition parameters. In the range of 0 to 10μmolNL -1 , kinetic curves showed a clear preference pattern following the ranking NH 4 + >NO 3 - >N-urea, where the preferential uptake of NH 4 + relative to NO 3 - was accentuated by an inhibitory effect of NH 4 + concentration on NO 3 - uptake capabilities. Conversely, under high nutrient concentrations, the preference for NH 4 + relative to NO 3 - was largely reduced, probably because of the existence of a low-affinity high capacity inducible NO 3 - uptake system. Ability to take up nutrients in darkness could not be defined as a competitive advantage for O. cf. ovata. Species competitiveness can also be defined from nutrient uptake kinetic parameters. A strong affinity for NH 4 + was observed for O. cf. ovata cells that may partly explain the success of this toxic species during the summer season in the Bay of Villefranche-sur-mer (France). Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Adolescent Exposure to Toxic Volatile Organic Chemicals From E-Cigarettes.

    Science.gov (United States)

    Rubinstein, Mark L; Delucchi, Kevin; Benowitz, Neal L; Ramo, Danielle E

    2018-04-01

    There is an urgent need to understand the safety of e-cigarettes with adolescents. We sought to identify the presence of chemical toxicants associated with e-cigarette use among adolescents. Adolescent e-cigarette users (≥1 use within the past 30 days, ≥10 lifetime e-cigarette use episodes) were divided into e-cigarette-only users (no cigarettes in the past 30 days, urine 4-[methylnitrosamino]-1-[3-pyridyl]-1-butanol [NNAL] level 30 pg/mL; n = 16), and never-using controls ( N = 20). Saliva was collected within 24 hours of the last e-cigarette use for analysis of cotinine and urine for analysis of NNAL and levels of 8 volatile organic chemical compounds. Bivariate analyses compared e-cigarette-only users with dual users, and regression analyses compared e-cigarette-only users with dual users and controls on levels of toxicants. The participants were 16.4 years old on average. Urine excretion of metabolites of benzene, ethylene oxide, acrylonitrile, acrolein, and acrylamide was significantly higher in dual users versus e-cigarette-only users (all P < .05). Excretion of metabolites of acrylonitrile, acrolein, propylene oxide, acrylamide, and crotonaldehyde were significantly higher in e-cigarette-only users compared with controls (all P < .05). Although e-cigarette vapor may be less hazardous than tobacco smoke, our findings can be used to challenge the idea that e-cigarette vapor is safe, because many of the volatile organic compounds we identified are carcinogenic. Messaging to teenagers should include warnings about the potential risk from toxic exposure to carcinogenic compounds generated by these products. Copyright © 2018 by the American Academy of Pediatrics.

  20. Development of multicomponent parts-per-billion-level gas standards of volatile toxic organic compounds

    International Nuclear Information System (INIS)

    Rhoderick, G.C.; Zielinski, W.L. Jr.

    1990-01-01

    This paper reports that the demand for stable, low-concentration multicomponent standards of volatile toxic organic compounds for quantifying national and state measurement of ambient air quality and hazardous waste incineration emissions has markedly increased in recent years. In response to this demand, a microgravimetric technique was developed and validated for preparing such standards; these standards ranged in concentration from several parts per million (ppm) down to one part per billion (ppb) and in complexity from one organic up to 17. Studies using the gravimetric procedure to prepare mixtures of different groups of organics. including multi-components mixtures in the 5 to 20 ppb range, revealed a very low imprecision. This procedure is based on the separate gravimetric introduction of individual organics into an evacuated gas cylinder, followed by the pressurized addition of a precalculated amount of pure nitrogen. Additional studies confirmed the long-term stability of these mixtures. The uncertainty of the concentrations of the individual organics at the 95% confidence level ranged from less than 1% relative at 1 ppm to less than 10% relative at 1 ppb. Over 100 primary gravimetric standards have been developed, validated, and used for certifying the concentrations of a variety of mixtures for monitoring studies

  1. Acute Toxicity of the Antifouling Compound Butenolide in Non-Target Organisms

    KAUST Repository

    Zhang, Yi-Fan

    2011-08-29

    Butenolide [5-octylfuran-2(5H)-one] is a recently discovered and very promising anti-marine-fouling compound. In this study, the acute toxicity of butenolide was assessed in several non-target organisms, including micro algae, crustaceans, and fish. Results were compared with previously reported results on the effective concentrations used on fouling (target) organisms. According to OECD\\'s guideline, the predicted no effect concentration (PNEC) was 0.168 µg l^(−1), which was among one of the highest in representative new biocides. Mechanistically, the phenotype of butenolide-treated Danio rerio (zebrafish) embryos was similar to the phenotype of the pro-caspase-3 over-expression mutant with pericardial edema, small eyes, small brains, and increased numbers of apoptotic cells in the bodies of zebrafish embryos. Butenolide also induced apoptosis in HeLa cells, with the activation of c-Jun N-terminal kinases (JNK), Bcl-2 family proteins, and caspases and proteasomes/lysosomes involved in this process. This is the first detailed toxicity and toxicology study on this antifouling compound.

  2. Intervention of D-glucose ameliorates the toxicity of streptozotocin in accessory sex organs of rat

    International Nuclear Information System (INIS)

    Vikram, A.; Tripathi, D.N.; Ramarao, P.; Jena, G.B.

    2008-01-01

    Streptozotocin (STZ) is a naturally occurring compound isolated from Streptomyces achromogens. It is used extensively for inducing diabetes in experimental animals. Diabetes mellitus is known to have proven adverse effects on male sexual organs and their reproductive functions. The atrophy of prostate gland and other organs of the genitourinary tract were observed in experimental diabetic animals. STZ exhibits a structural resemblance to D-glucose due to the presence of sugar moiety in its structure. Pancreatic β-cells mainly contain GLUT1 and GLUT2 glucose transporters. Possibly due to structural resemblance, STZ and D-glucose, share a common recognition site for entry into the β-cells. The objective of the present study is to evaluate the effect of D-glucose on STZ-induced toxicity in accessory sex organs of male rats. Animals were kept on overnight fasting. One group received vehicle and served as negative control, while all other groups were given STZ (45 mg/kg). Animals that received only STZ served as positive control. The effect of D-glucose was studied on STZ treated animals with different dosage of D-glucose (250, 500, 1000 and 2000 mg/kg). Restoration of body weight, plasma glucose and plasma insulin was evident only at 1000 and 2000 mg/kg of D-glucose. The protective effect of D-glucose is evident only when it is administered simultaneously with STZ. In the present investigation, we report that simultaneous administration of D-glucose along with STZ ameliorates STZ-induced toxicity. This is evident from the restoration of accessory sex organ's weight, cellular morphology as well as insulin level

  3. Wood Dust

    Science.gov (United States)

    Learn about wood dust, which can raise the risk of cancers of the paranasal sinuses and nasal cavity. High amounts of wood dust are produced in sawmills, and in the furniture-making, cabinet-making, and carpentry industries.

  4. A Raman spectroscopic study of organic matter in interplanetary dust particles and meteorites using multiple wavelength laser excitation

    Science.gov (United States)

    Starkey, N. A.; Franchi, I. A.; Alexander, C. M. O'd.

    2013-10-01

    Raman spectroscopy was used to investigate insoluble organic matter (IOM) from a range of chondritic meteorites, and a suite of interplanetary dust particles (IDPs). Three monochromatic excitation wavelengths (473 nm, 514 nm, 632 nm) were applied sequentially to assess variations in meteorite and IDP Raman peak parameters (carbon D and G bands) as a function of excitation wavelength (i.e., dispersion). Greatest dispersion occurs in CVs > OCs > CMs > CRs with type 3 chondrites compared at different excitation wavelengths displaying conformable relationships, in contrast to type 2 chondrites. These findings indicate homogeneity in the structural nature of type 3 chondrite IOM, while organic matter (OM) in type 2 chondrites appears to be inherently more heterogeneous. If type 2 and type 3 chondrite IOM shares a common source, then thermal metamorphism may have a homogenizing effect on the originally more heterogeneous OM. IDP Raman G bands fall on an extension of the trend displayed by chondrite IOM, with all IDPs having Raman parameters indicative of very disordered carbon, with almost no overlap with IOM. The dispersion effect displayed by IDPs is most similar to CMs for the G band, but intermediate between CMs and CRs for the D band. The existence of some overlapping Raman features in the IDPs and IOM indicates that their OM may share a common origin, but the IDPs preserve more pristine OM that may have been further disordered by ion irradiation. H, C, and N isotopic data for the IDPs reveal that the disordered carbon in IDPs corresponds with higher δ15N and lower δ13C.

  5. The relationship between metal toxicity and biotic ligand binding affinities in aquatic and soil organisms: a review.

    Science.gov (United States)

    Ardestani, Masoud M; van Straalen, Nico M; van Gestel, Cornelis A M

    2014-12-01

    The biotic ligand model (BLM) is a theoretical, potentially mechanistic approach to assess metal bioavailability in soil and aquatic systems. In a BLM, toxicity is linked to the fraction of biotic ligand occupied, which in turn, depends on the various components of the solution, including activity of the metal. Bioavailability is a key factor in determining toxicity and uptake of metals in organisms. In this study, the present status of BLM development for soil and aquatic organisms is summarized. For all species and all metals, toxicity was correlated with the conditional biotic ligand binding constants. For almost all organisms, values for Ag, Cu, and Cd were higher than those for Zn and Ni. The constants derived for aquatic systems seem to be equally valid for soil organisms, but in the case of soils, bioavailability from the soil solution is greatly influenced by the presence of the soil solid phase. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Comparison of metal toxic impacts between aquatic and terrestrial organisms: is the free ion concentration a sufficient descriptor?

    DEFF Research Database (Denmark)

    Owsianiak, Mikolaj; Rosenbaum, Ralph K.; Larsen, Henrik Fred

    2011-01-01

    Characterization of metal toxic impacts in comparative risk assessment and life cycle impact assessment (LCIA) should take into account metal speciation and interactions with soil/water organic constituents, because these mechanisms control metal bioavailability and may influence their toxic...... that the free metal ion is an appropriate “general”descriptor of metal toxicity. Results for 128 laboratory tests on Daphnia magna exposed to copper ions (Cu2+) in water show that variation of several orders of magnitude are observed between the toxicity tests. These variations may be a result of the inability...... of magnitude difference occur for the extreme case of barley (Hordeum vulgare). Given the scarcity of terrestrial effect data compared to aquatic data, reliable and transparent, mechanistic-based predictions of terrestrial toxic impacts from aquatic effect data would be an important step ahead in the context...

  7. Valorization of GaN based metal-organic chemical vapor deposition dust a semiconductor power device industry waste through mechanochemical oxidation and leaching: A sustainable green process.

    Science.gov (United States)

    Swain, Basudev; Mishra, Chinmayee; Lee, Chan Gi; Park, Kyung-Soo; Lee, Kun-Jae

    2015-07-01

    Dust generated during metal organic vapor deposition (MOCVD) process of GaN based semiconductor power device industry contains significant amounts of gallium and indium. These semiconductor power device industry wastes contain gallium as GaN and Ga0.97N0.9O0.09 is a concern for the environment which can add value through recycling. In the present study, this waste is recycled through mechanochemical oxidation and leaching. For quantitative recovery of gallium, two different mechanochemical oxidation leaching process flow sheets are proposed. In one process, first the Ga0.97N0.9O0.09 of the MOCVD dust is leached at the optimum condition. Subsequently, the leach residue is mechanochemically treated, followed by oxidative annealing and finally re-leached. In the second process, the MOCVD waste dust is mechanochemically treated, followed by oxidative annealing and finally leached. Both of these treatment processes are competitive with each other, appropriate for gallium leaching and treatment of the waste MOCVD dust. Without mechanochemical oxidation, 40.11 and 1.86 w/w% of gallium and Indium are leached using 4M HCl, 100°C and pulp density of 100 kg/m(3,) respectively. After mechanochemical oxidation, both these processes achieved 90 w/w% of gallium and 1.86 w/w% of indium leaching at their optimum condition. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. PAHs concentration and toxicity in organic solvent extracts of atmospheric particulate matter and sea sediments.

    Science.gov (United States)

    Ozaki, Noriatsu; Takeuchi, Shin-ya; Kojima, Keisuke; Kindaichi, Tomonori; Komatsu, Toshiko; Fukushima, Takehiko

    2012-01-01

    The concentration of polycyclic aromatic hydrocarbons (PAHs) and the toxicity to marine bacteria (Vibrio fischeri) were measured for the organic solvent extracts of sea sediments collected from an urban watershed area (Hiroshima Bay) of Japan and compared with the concentrations and toxicity of atmospheric particulate matter (PM). In atmospheric PM, the PAHs concentration was highest in fine particulate matter (FPM) collected during cold seasons. The concentrations of sea sediments were 0.01-0.001 times those of atmospheric PM. 1/EC50 was 1-10 L g(-1) PM for atmospheric PM and 0.1-1 L g(-1) dry solids for sea sediments. These results imply that toxic substances from atmospheric PM are diluted several tens or hundreds of times in sea sediments. The ratio of the 1/EC50 to PAHs concentration ((1/EC50)/16PAHs) was stable for all sea sediments (0.1-1 L μg(-1) 16PAHs) and was the same order of magnitude as that of FPM and coarse particulate matter (CPM). The ratio of sediments collected from the west was more similar to that of CPM while that from the east was more similar to FPM, possibly because of hydraulic differences among water bodies. The PAHs concentration pattern analyses (principal component analysis and isomer ratio analysis) were conducted and the results showed that the PAHs pattern in sea sediments was quite different to that of FPM and CPM. Comparison with previously conducted PAHs analyses suggested that biomass burning residues comprised a major portion of these other sources.

  9. Nickel toxicity to benthic organisms: The role of dissolved organic carbon, suspended solids, and route of exposure.

    Science.gov (United States)

    Custer, Kevin W; Hammerschmidt, Chad R; Burton, G Allen

    2016-01-01

    Nickel bioavailability is reduced in the presence of dissolved organic carbon (DOC), suspended solids (TSS), and other complexing ligands; however, no studies have examined the relative importance of Ni exposure through different compartments (water, sediment, food). Hyalella azteca and Lymnaea stagnalis were exposed to Ni-amended water, sediment, and food, either separately or in combination. Both organisms experienced survival and growth effects in several Ni compartment tests. The DOC amendments attenuated L. stagnalis Ni effects (survival, growth, and (62)Ni bioaccumulation), and presence of TSS exposures demonstrated both protective and synergistic effects on H. azteca and L. stagnalis. (62)Ni trophic transfer from food to H. azteca and L. stagnalis was negligible; however, bioaccumulating (62)Ni was attributed to (62)Ni-water ((62)Ni flux from food), (62)Ni-TSS, and (62)Ni-food. Overall, H. azteca and L. stagnalis Ni compartment toxicity increased in the following order: Ni-water > Ni-sediment > Ni-all (water, sediment, food) > Ni-food. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Endosulfan Toxicity to Anabas testudineus and Histopathological Changes on Vital Organs

    Directory of Open Access Journals (Sweden)

    Nordin I.L.

    2018-01-01

    Full Text Available The toxicity of endosulfan, an organochlorine type insecticide to a commonly consumed freshwater fish species, A. testudineus (40.68±9.03 g; 13.49±0.99 cm, was investigated under static conditions. The nominal endosulfan concentrations ranging from 10 to 80 μg/L subjected to the fish population results in 96-hour median lethal concentration, LC50, of 35.2±3.99 μg/L. The toxicity is a function of both endosulfan concentration and exposure time (p>0.05. Histopathological analysis on vital organs exposed to sublethal concentrations indicates that structural changes started at sublethal dose and the effects aggravated with increasing endosulfan concentration. Gill was found to experience aneurism, hyperplasia in lamellar and autolysis of mast cell. Pyknotic nuclei and necrosis were observed in liver cell, while the lumen of renal tubule was found to narrow and haemorrhage was observed in cytoplasm cell. High LC50 compared to other fishes indicates that A. testudineus has high tolerant to endosulfan, however, endosulfan slowly alters the fish biochemistry and is potentially transferable to human

  11. Estimation of the toxicity of pollutants to marine phytoplanktonic and zooplanktonic organisms

    International Nuclear Information System (INIS)

    1989-01-01

    One of the basic components of the action plans sponsored by UNEP in the framework of the Regional Seas Programme is the assessment of the state of the marine environment and of its resources, and of the sources and trends of the pollution, and the impact of pollution on human health, marine ecosystems, and amenities. In order to ensure that the data obtained through this assessment can be compared on a world-wide basis and thus contribute to the Global Environment Monitoring System (GEMS) of UNEP, a set of Reference Methods and Guidelines for marine pollution studies are being developed as part of a programme of comprehensive technical support which includes the provision of expert advice, reference methods and materials, training and data quality assurance. This reference method describes procedures for estimating the toxicity of pollutants to marine phytoplankton and zooplankton. Procedures are given for estimating the media effective concentrations (EC50) of toxicants to phytoplankton, and the minimum algistatic concentration (MAC-5). For zooplankton, procedures are given for determining median lethal concentrations. Organisms are exposed to each of a range of concentrations of the test substance. For phytoplankton, the median effective concentration (EC50) is estimated in terms of the number of individuals surviving, the biomass of individuals surviving, or the chlorophyll content of the individuals surviving. For zooplankton, the media lethal concentration (LC50) is estimated by conventional log-probit analysis of the mortality data

  12. Endosulfan Toxicity to Anabas testudineus and Histopathological Changes on Vital Organs

    Science.gov (United States)

    Nordin, I. L.; Ibrahim, N.; Ahmad, S. A.; Hamidin, N. l.; Dahalan, F. A.; Abd. Shukor, M. Y.

    2018-03-01

    The toxicity of endosulfan, an organochlorine type insecticide to a commonly consumed freshwater fish species, A. testudineus (40.68±9.03 g; 13.49±0.99 cm), was investigated under static conditions. The nominal endosulfan concentrations ranging from 10 to 80 μg/L subjected to the fish population results in 96-hour median lethal concentration, LC50, of 35.2±3.99 μg/L. The toxicity is a function of both endosulfan concentration and exposure time (p>0.05). Histopathological analysis on vital organs exposed to sublethal concentrations indicates that structural changes started at sublethal dose and the effects aggravated with increasing endosulfan concentration. Gill was found to experience aneurism, hyperplasia in lamellar and autolysis of mast cell. Pyknotic nuclei and necrosis were observed in liver cell, while the lumen of renal tubule was found to narrow and haemorrhage was observed in cytoplasm cell. High LC50 compared to other fishes indicates that A. testudineus has high tolerant to endosulfan, however, endosulfan slowly alters the fish biochemistry and is potentially transferable to human

  13. Removal of organic matter and toxicity in hospital wastewaters by ozone

    International Nuclear Information System (INIS)

    Grisales Penagos, Dayana; Ortega Lopez, Joela; Rodriguez Chaparro, Tatiana

    2012-01-01

    Hospital wastewaters are considered to be one of the major sources of emergent contaminants as result of the dairy activities and excretion of the patients. Several studies have demonstrated that these compounds are not easily removed in conventional wastewater treatments that use biological process. This study evaluated the removal of the organic matter present in real hospital effluent applying ozone at different pH conditions (3,0, 6,7, 10). Parameters such as UV254, biodegradability ratio (COD/BOD) and color (VIS436) were measured. Moreover, it was assessed the acute toxicity with Allium cepa L. The results demonstrated that with an ozone dosage of 187 mgO3/h and pH = 10 the biodegradability increased by 70% and the acute toxicity decreased by 62%, whereas for pH =3,0 both UV254 and color removal was notable. The ozone application seems to be a viable alternative to treat hospital effluents as a pretreatment of a biological process.

  14. Removal of organic matter and toxicity in hospital wastewaters by ozone

    International Nuclear Information System (INIS)

    Grisales Penagos Dayana; Ortega Lopez Joela; Rodriguez Chaparro Tatiana

    2012-01-01

    Hospital wastewaters are considered to be one of the major sources of emergent contaminants as result of the dairy activities and excretion of the patients. Several studies have demonstrated that these compounds are not easily removed in conventional wastewater treatments that use biological process. This study evaluated the removal of the organic matter present in real hospital effluent applying ozone at different pH conditions (3,0, 6,7, 10). Parameters such as UV254, biodegradability ratio (COD/BOD) and color (VIS436) were measured. Moreover, it was assessed the acute toxicity with Allium cepa L. The results demonstrated that with an ozone dosage of 187 MgO 3 /h and pH = 10 the biodegradability increased by 70% and the acute toxicity decreased by 62%, whereas for pH =3,0 both UV254 and color removal was notable. The ozone application seems to be a viable alternative to treat hospital effluents as a pretreatment of a biological process. Allium cepa L., biodegradability, emergent compounds, recalcitrance

  15. A Broad Spectrum Catalytic System for Removal of Toxic Organics from Water by Deep Oxidation - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Ayusman

    2000-12-01

    A most pressing need for the DOE environmental management program is the removal of toxic organic compounds present in groundwater and soil at specific DOE sites. While several remediation procedures have been proposed, they suffer from one or more drawbacks. The objective of the present research was to develop new catalytic procedures for the removal of toxic organic compounds from the environment through their deep oxidation to harmless products. In water, metallic palladium was found to catalyze the deep oxidation of a wide variety of toxic organic compounds by dioxygen at 80-90 C in the presence of carbon monoxide or dihydrogen. Several classes of organic compounds were examined: benzene, phenol and substituted phenols, nitro and halo organics, organophosphorus, and organosulfur compounds. In every case, deep oxidation to carbon monoxide, carbon dioxide, and water occurred in high yields, resulting in up to several hundred turnovers over a 24 hour period. For substrates susceptible to hydrogenation, the conversions were generally high with dihydrogen than with carbon monoxide. It is clear from the results obtained that we have discovered an exceptionally versatile catalytic system for the deep oxidation of toxic organic compounds in water. This system possesses several attractive features not found simultaneously in other reported systems. These are (a) the ability to directly utilize dioxygen as the oxidant, (b) the ability to carry out the deep oxidation of a particularly wide range of functional organics, and (c) the ease of recovery of the catalyst by simple filtration.

  16. Metabolic responses of Eisenia fetida after sub-lethal exposure to organic contaminants with different toxic modes of action

    International Nuclear Information System (INIS)

    McKelvie, Jennifer R.; Wolfe, David M.; Celejewski, Magda A.; Alaee, Mehran; Simpson, Andre J.; Simpson, Myrna J.

    2011-01-01

    Nuclear magnetic resonance (NMR) - based metabolomics has the potential to identify toxic responses of contaminants within a mixture in contaminated soil. This study evaluated the metabolic response of Eisenia fetida after exposure to an array of organic compounds to determine whether contaminant-specific responses could be identified. The compounds investigated in contact tests included: two pesticides (carbaryl and chlorpyrifos), three pharmaceuticals (carbamazephine, estrone and caffeine), two persistent organohalogens (Aroclor 1254 and PBDE 209) and two industrial compounds (nonylphenol and dimethyl phthalate). Control and contaminant-exposed metabolic profiles were distinguished using principal component analysis and potential contaminant-specific biomarkers of exposure were found for several contaminants. These results suggest that NMR-based metabolomics offers considerable promise for differentiating between the different toxic modes of action (MOA) associated with sub-lethal toxicity to earthworms. - Highlights: → NMR-based earthworm metabolomic analysis of the toxic mode of action of various environmental contaminants. → Organic chemicals with different toxic modes of action resulted in varied metabolomic responses for E. fetida. → NMR-based metabolomics differentiates between the different modes of action associated with sub-lethal toxicity. - 1 H NMR metabolomics was used to identify potential biomarkers of organic contaminant exposure in Eisenia fetida earthworms.

  17. Metabolic responses of Eisenia fetida after sub-lethal exposure to organic contaminants with different toxic modes of action

    Energy Technology Data Exchange (ETDEWEB)

    McKelvie, Jennifer R.; Wolfe, David M.; Celejewski, Magda A. [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada); Alaee, Mehran [Environment Canada, 867 Lakeshore Rd., P.O. Box 5050, Burlington, ON L7R 4A6 (Canada); Simpson, Andre J. [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada); Simpson, Myrna J., E-mail: myrna.simpson@utoronto.ca [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada)

    2011-12-15

    Nuclear magnetic resonance (NMR) - based metabolomics has the potential to identify toxic responses of contaminants within a mixture in contaminated soil. This study evaluated the metabolic response of Eisenia fetida after exposure to an array of organic compounds to determine whether contaminant-specific responses could be identified. The compounds investigated in contact tests included: two pesticides (carbaryl and chlorpyrifos), three pharmaceuticals (carbamazephine, estrone and caffeine), two persistent organohalogens (Aroclor 1254 and PBDE 209) and two industrial compounds (nonylphenol and dimethyl phthalate). Control and contaminant-exposed metabolic profiles were distinguished using principal component analysis and potential contaminant-specific biomarkers of exposure were found for several contaminants. These results suggest that NMR-based metabolomics offers considerable promise for differentiating between the different toxic modes of action (MOA) associated with sub-lethal toxicity to earthworms. - Highlights: > NMR-based earthworm metabolomic analysis of the toxic mode of action of various environmental contaminants. > Organic chemicals with different toxic modes of action resulted in varied metabolomic responses for E. fetida. > NMR-based metabolomics differentiates between the different modes of action associated with sub-lethal toxicity. - {sup 1}H NMR metabolomics was used to identify potential biomarkers of organic contaminant exposure in Eisenia fetida earthworms.

  18. Method to prepare essentially organic waste liquids containing radioactive or toxic materials

    International Nuclear Information System (INIS)

    Baehr, W.; Drobnik, S.H.; Hild, W.; Kroebel, R.; Meyer, A.; Naumann, G.

    1976-01-01

    Waste solutions occuring in nuclear technology containing radioactive or toxic materials can be solidified by mixing with a polymerisable mixture with subsequent polymerization. An improvement of this method, especially for liquids in which the radioactive components are present as organic compounds is achieved by adding a mixture of at least one monomeric vinyl compound, at least one polyvinyl compound and appropriate catalysts and by polymerizing at temperatures between 15 and 150 0 C. Should the waste liquid contain mineral acid, this is first neutralized by the addition of CaO or MgO. In processing oils or soaps, the addition of swelling agent for polystyrol resins is advantageous. 16 examples illustrate the invention. (UWI) [de

  19. Toxicity risk of non-target organs at risk receiving low-dose radiation: case report

    International Nuclear Information System (INIS)

    Shueng, Pei-Wei; Lin, Shih-Chiang; Chang, Hou-Tai; Chong, Ngot-Swan; Chen, Yu-Jen; Wang, Li-Ying; Hsieh, Yen-Ping; Hsieh, Chen-Hsi

    2009-01-01

    The spine is the most common site for bone metastases. Radiation therapy is a common treatment for palliation of pain and for prevention or treatment of spinal cord compression. Helical tomotherapy (HT), a new image-guided intensity modulated radiotherapy (IMRT), delivers highly conformal dose distributions and provides an impressive ability to spare adjacent organs at risk, thus increasing the local control of spinal column metastases and decreasing the potential risk of critical organs under treatment. However, there are a lot of non-target organs at risk (OARs) occupied by low dose with underestimate in this modern rotational IMRT treatment. Herein, we report a case of a pathologic compression fracture of the T9 vertebra in a 55-year-old patient with cholangiocarcinoma. The patient underwent HT at a dose of 30 Gy/10 fractions delivered to T8-T10 for symptom relief. Two weeks after the radiotherapy had been completed, the first course of chemotherapy comprising gemcitabine, fluorouracil, and leucovorin was administered. After two weeks of chemotherapy, however, the patient developed progressive dyspnea. A computed tomography scan of the chest revealed an interstitial pattern with traction bronchiectasis, diffuse ground-glass opacities, and cystic change with fibrosis. Acute radiation pneumonitis was diagnosed. Oncologists should be alert to the potential risk of radiation toxicities caused by low dose off-targets and abscopal effects even with highly conformal radiotherapy

  20. The chronic toxicity of molybdate to marine organisms. I. Generating reliable effects data

    International Nuclear Information System (INIS)

    Heijerick, D.G.; Regoli, L.; Stubblefield, W.

    2012-01-01

    A scientific research program was initiated by the International Molybdenum Association (IMOA) which addressed identified gaps in the environmental toxicity data for the molybdate ion (MoO 4 2− ). These gaps were previously identified during the preparation of EU-REACH-dossiers for different molybdenum compounds (European Union regulation on Registration, Evaluation, Authorization and Restriction of Chemical substances; EC, 2006). Evaluation of the open literature identified few reliable marine ecotoxicological data that could be used for deriving a Predicted No-Effect Concentration (PNEC) for the marine environment. Rather than calculating a PNEC marine using the assessment factor methodology on a combined freshwater/marine dataset, IMOA decided to generate sufficient reliable marine chronic data to permit derivation of a PNEC by means of the more scientifically robust species sensitivity distribution (SSD) approach (also called the statistical extrapolation approach). Nine test species were chronically exposed to molybdate (added as sodium molybdate dihydrate, Na 2 MoO 4 ·2H 2 O) according to published standard testing guidelines that are acceptable for a broad range of regulatory purposes. The selected test organisms were representative for typical marine trophic levels: micro-algae/diatom (Phaeodactylum tricornutum, Dunaliella tertiolecta), macro-alga (Ceramium tenuicorne), mysids (Americamysis bahia), copepod (Acartia tonsa), fish (Cyprinodon variegatus), echinoderms (Dendraster exentricus, Strongylocentrotus purpuratus) and molluscs (Mytilus edulis, Crassostrea gigas). Available NOEC/EC 10 levels ranged between 4.4 mg Mo/L (blue mussel M. edulis) and 1174 mg Mo/L (oyster C. gigas). Using all available reliable marine chronic effects data that are currently available, a HC 5,50% (median hazardous concentration affecting 5% of the species) of 5.74 (mg Mo)/L was derived with the statistical extrapolation approach, a value that can be used for national and

  1. The chronic toxicity of molybdate to marine organisms. I. Generating reliable effects data

    Energy Technology Data Exchange (ETDEWEB)

    Heijerick, D.G., E-mail: Dagobert.heijerick@arche-consulting.be [ARCHE - Assessing Risks of Chemicals, Stapelplein 70 Bus 104, Gent (Belgium); Regoli, L. [International Molybdenum Association, 4 Heathfield Terrace, London, W4 4JE (United Kingdom); Stubblefield, W. [Oregon State University, Department of Environmental and Molecular Toxicology, 421 Weniger Hall, Corvallis, OR 97331 (United States)

    2012-07-15

    A scientific research program was initiated by the International Molybdenum Association (IMOA) which addressed identified gaps in the environmental toxicity data for the molybdate ion (MoO{sub 4}{sup 2-}). These gaps were previously identified during the preparation of EU-REACH-dossiers for different molybdenum compounds (European Union regulation on Registration, Evaluation, Authorization and Restriction of Chemical substances; EC, 2006). Evaluation of the open literature identified few reliable marine ecotoxicological data that could be used for deriving a Predicted No-Effect Concentration (PNEC) for the marine environment. Rather than calculating a PNEC{sub marine} using the assessment factor methodology on a combined freshwater/marine dataset, IMOA decided to generate sufficient reliable marine chronic data to permit derivation of a PNEC by means of the more scientifically robust species sensitivity distribution (SSD) approach (also called the statistical extrapolation approach). Nine test species were chronically exposed to molybdate (added as sodium molybdate dihydrate, Na{sub 2}MoO{sub 4}{center_dot}2H{sub 2}O) according to published standard testing guidelines that are acceptable for a broad range of regulatory purposes. The selected test organisms were representative for typical marine trophic levels: micro-algae/diatom (Phaeodactylum tricornutum, Dunaliella tertiolecta), macro-alga (Ceramium tenuicorne), mysids (Americamysis bahia), copepod (Acartia tonsa), fish (Cyprinodon variegatus), echinoderms (Dendraster exentricus, Strongylocentrotus purpuratus) and molluscs (Mytilus edulis, Crassostrea gigas). Available NOEC/EC{sub 10} levels ranged between 4.4 mg Mo/L (blue mussel M. edulis) and 1174 mg Mo/L (oyster C. gigas). Using all available reliable marine chronic effects data that are currently available, a HC{sub 5,50%} (median hazardous concentration affecting 5% of the species) of 5.74 (mg Mo)/L was derived with the statistical extrapolation approach, a

  2. Radioisotopic methods - determination of action of toxic chemicals to food - digestion organs

    International Nuclear Information System (INIS)

    Saitmuratova, O.H.; Tursunov, E.A.

    2004-01-01

    Full text: It is known that poison chemicals used for agriculture enter in an organism of human and animal by various ways and affect key processes in cells and tissues. These processes are investigated insufficiently, nevertheless, investigating actions of chemicals on bodies and tissues it, is possible to define a degree of its toxicity. In the present work influence of defoliant drop and insecticide buldok on protein synthetic ability (PSA) of cells of digestive bodies (a liver, a stomach and duodenal gut) is investigated. Experiments carried out on white not purebred rats - males in weight 160-180 g, which entered drop in doze of 1/5 IC 50 5350 mg/kg, buldok 1/5 IC 50 400 mg/kg and 14 C-glutamine acid with the general activity 1 mk Curie (2.2*106 imp/min) in one hour up to slaughter. A control animal in parallel entered a physiological solution. In animals hammered in one hour and investigated inclusion 14 C- glutamine acids in structure of synthesized proteins of a liver, a stomach and duodenal gut. Action of preparations checked in 1, 24 and 72 hours after introduction. As have shown the received data drop suppresses PSA in cells of a liver on 14 % and 45 % in 24 and 72 hours accordingly; in a stomach - on 32 % and 34 %; in duodenal gut - on 39 % and 48 %. PSA it is more suppressed in a stomach. Further process is gradually restored in all bodies. Buldok in the same terms suppresses PSA in a liver on 4 % and 25 %; in a stomach of 4 % and 16 % and in duodenal gut on the contrary are raised with formation of protein on 27 %. The next day there is restoration PSA in all investigated bodies. From the received data it is visible, that defoliant drop as well as insecticide buldok influence on PSA cells, but action of drop is stronger, than buldok. It will be coordinated to earlier received data on change of morphological structures under influence of these pesticides. Though drop and buldok differ on dynamics of action on PSA digestive bodies, they are not strongly

  3. Delivery of Exogenous Complex Organic Compounds by Solar System Small Bodies and Space Dusts and Its Relevance to Origins of Life

    Science.gov (United States)

    Kobayashi, Kensei; Fushimi, Hidehiko; Motoyama, Takuya; Kaneko, Takeo; Obayashi, Yumiko; Yoshida, Satoshi; Mita, Hajime; Yabuta, Hikaru; Okudaira, Kyoko; Hashimoto, Hirofumi; Yokobori, Shin-Ichi; Yamagishi, Akihiko

    A wide variety of organic compounds including amino acid precursors have been detected in such extraterrestrial bodies as carbonaceous chondrites and comets. It was suggested that these organics were formed in quite cold environments. We irradiated frozen mixtures of possible constituents of ice mantles of interstellar dust particles including water, methanol and ammonia with high-energy heavy ions from HIMAC, National Institute of Radiological Science, Japan. Amino acid precursors with complex structures were detected whose molecular weights are up to a few thousands. Such complex amino acid precursors are much stronger than free amino acids against radiation. Such organics could have been incorporated in solar system small bodies after the formation of the solar system and delivered to the primitive Earth. Possible carriers of such organics are meteorites, comets and interplanetary dust particles (IDPs) that were formed from comets and meteorites. It is suggested that IDPs brought much more organics than meteorites and comets. However, nature of organics in IDPs is little known, since they have been collected only in terrestrial biosphere. We are planning a space experiments named Tanpopo, where IDPs would be collected in aerogel equipped on the Exposure Facility of the International Space Station. In addition, amino acids and their relating compounds would be exposed to space environments to see their possible alteration processes in the interplanetary space. We will report some preliminary results for the preparation of the mission including the capture of amino acid-containing particles at high velocity with ultra-low density aerogel.

  4. Theory of hysteresis during electron heating of electromagnetic wave scattering by self-organized dust structures in complex plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Tsytovich, Vadim, E-mail: tsytov@lpi.ru [A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilova str. 38, Moscow 119991 (Russian Federation); Max Planck Institute for Extraterrestrial Physics, Garching (Germany); Gusein-zade, Namik; Ignatov, Alexander [A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilova str. 38, Moscow 119991 (Russian Federation); Medicobiologic Faculty, Pirogov Russian National Research Medical University, Moscow (Russian Federation)

    2015-07-15

    Dust structuring is a natural and universal process in complex plasmas. The scattering of electromagnetic waves by dust structures is governed by the factor of coherency, i.e., the total number of coherent electrons in a single structure. In the present paper, we consider how the factor of coherency changes due to additional pulse electron heating and show that it obeys a hysteresis. After the end of the pulse heating, the scattering intensity differs substantially from that before heating. There are three necessary conditions for scattering hysteresis: first, the radiation wavelength should be larger than the pattern (structure) size; second, the total number of coherent electrons confined by the structure should be large; and third, the heating pulse duration should be shorter than the characteristic time of dust structure formation. We present the results of numerical calculations using existing models of self-consistent dust structures with either positively or negatively charged dust grains. It is shown that, depending on the grain charge and the ionization rate, two types of hysteresis are possible: one with a final increase of the scattering and the other with a final decrease of the scattering. It is suggested that the hysteresis of coherent scattering can be used as a tool in laboratory experiments and that it can be a basic mechanism explaining the observed hysteresis in radar scattering by noctilucent clouds during active experiments on electron heating in mesosphere.

  5. Silver Nanoparticles in the Lung: Toxic Effects and Focal Accumulation of Silver in Remote Organs

    Directory of Open Access Journals (Sweden)

    Martin Wiemann

    2017-12-01

    Full Text Available The distribution of silver (Ag into remote organs secondary to the application of Ag nanoparticles (Ag-NP to the lung is still incompletely understood and was investigated in the rat with imaging methods. Dose-finding experiments were carried out with 50 nm- or 200 nm-sized polyvinyl pyrrolidine (PVP-coated Ag-NP using alveolar macrophages in vitro and female rats, which received Ag-NP via intratracheal instillation. In the main study, we administered 37.5–300 µg per rat lung of the more toxic Ag50-PVP and assessed the broncho-alveolar lavage fluid (BALF for inflammatory cells, total protein and fibronectin after three and 21 days. In parallel, lung tissue was analysed for DNA double-strand breaks and altered cell proliferation. While 75–150 µg Ag50-PVP per rat lung caused a reversible inflammation, 300 µg led to DNA damage, accelerated cell proliferation and progressively increasing numbers of neutrophilic granulocytes. Ag accumulation was significant in homogenates of liver and other peripheral organs upon lung dose of ≥75 µg. Quantitative laser-ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS combined with enhanced dark field microscopy and autometallography revealed focal accumulations of Ag and/or Ag-NP in sections of peripheral organs: mediastinal lymph nodes contained Ag-NP especially in peripheral macrophages and Ag in argyrophilic fibres. In the kidney, Ag had accumulated within proximal tubuli, while renal filter structures contained no Ag. Discrete localizations were also observed in immune cells of liver and spleen. Overall, the study shows that concentrations of Ag-NP, which elicit a transient inflammation in the rat lung, lead to focal accumulations of Ag in peripheral organs, and this might pose a risk to particular cell populations in remote sites.

  6. Toxicity of single walled carbon nanotubes to rainbow trout (Oncorhynchus mykiss): Respiratory toxicity, organ pathologies, and other physiological effects

    International Nuclear Information System (INIS)

    Smith, Catherine J.; Shaw, Benjamin J.; Handy, Richard D.

    2007-01-01

    Mammalian studies have raised concerns about the toxicity of carbon nanotubes (CNTs), but there is very limited data on ecotoxicity to aquatic life. We describe the first detailed report on the toxicity of single walled carbon nanotubes (SWCNT) to rainbow trout, using a body systems approach. Stock solutions of dispersed SWCNT were prepared using a combination of solvent (sodium dodecyl sulphate, SDS) and sonication. A semi-static test system was used to expose rainbow trout to either a freshwater control, solvent control, 0.1, 0.25 or 0.5 mg l -1 SWCNT for up to 10 days. SWCNT exposure caused a dose-dependent rise in ventilation rate, gill pathologies (oedema, altered mucocytes, hyperplasia), and mucus secretion with SWCNT precipitation on the gill mucus. No major haematological or blood disturbances were observed in terms of red and white blood cell counts, haematocrits, whole blood haemoglobin, and plasma Na + or K + . Tissue metal levels (Na + , K + , Ca 2+ , Cu, Zn and Co) were generally unaffected. However some dose-dependent changes in brain and gill Zn or Cu were observed (but not tissue Ca 2+ ), that were also partly attributed to the solvent. SWCNT exposure caused statistically significant increases in Na + K + -ATPase activity in the gills and intestine, but not in the brain. Thiobarbituric acid reactive substances (TBARS) showed dose-dependent and statistically significant decreases especially in the gill, brain and liver during SWCNT exposure compared to controls. SWCNT exposure caused statistically significant increases in the total glutathione levels in the gills (28%) and livers (18%), compared to the solvent control. Total glutathione in the brain and intestine remained stable in all treatments. Pathologies in the brain included possible aneurisms or swellings on the ventral surface of the cerebellum. Liver cells exposed to SWCNT showed condensed nuclear bodies (apoptotic bodies) and cells in abnormal nuclear division. Overt fatty change or wide

  7. Toxicity of single walled carbon nanotubes to rainbow trout (Oncorhynchus mykiss): Respiratory toxicity, organ pathologies, and other physiological effects

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Catherine J. [Ecotoxicology and Stress Biology Research Group, School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Shaw, Benjamin J. [Ecotoxicology and Stress Biology Research Group, School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Handy, Richard D. [Ecotoxicology and Stress Biology Research Group, School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)]. E-mail: rhandy@plymouth.ac.uk

    2007-05-01

    Mammalian studies have raised concerns about the toxicity of carbon nanotubes (CNTs), but there is very limited data on ecotoxicity to aquatic life. We describe the first detailed report on the toxicity of single walled carbon nanotubes (SWCNT) to rainbow trout, using a body systems approach. Stock solutions of dispersed SWCNT were prepared using a combination of solvent (sodium dodecyl sulphate, SDS) and sonication. A semi-static test system was used to expose rainbow trout to either a freshwater control, solvent control, 0.1, 0.25 or 0.5 mg l{sup -1} SWCNT for up to 10 days. SWCNT exposure caused a dose-dependent rise in ventilation rate, gill pathologies (oedema, altered mucocytes, hyperplasia), and mucus secretion with SWCNT precipitation on the gill mucus. No major haematological or blood disturbances were observed in terms of red and white blood cell counts, haematocrits, whole blood haemoglobin, and plasma Na{sup +} or K{sup +}. Tissue metal levels (Na{sup +}, K{sup +}, Ca{sup 2+}, Cu, Zn and Co) were generally unaffected. However some dose-dependent changes in brain and gill Zn or Cu were observed (but not tissue Ca{sup 2+}), that were also partly attributed to the solvent. SWCNT exposure caused statistically significant increases in Na{sup +}K{sup +}-ATPase activity in the gills and intestine, but not in the brain. Thiobarbituric acid reactive substances (TBARS) showed dose-dependent and statistically significant decreases especially in the gill, brain and liver during SWCNT exposure compared to controls. SWCNT exposure caused statistically significant increases in the total glutathione levels in the gills (28%) and livers (18%), compared to the solvent control. Total glutathione in the brain and intestine remained stable in all treatments. Pathologies in the brain included possible aneurisms or swellings on the ventral surface of the cerebellum. Liver cells exposed to SWCNT showed condensed nuclear bodies (apoptotic bodies) and cells in abnormal nuclear

  8. Effect of Soil Filtration and Ozonation in the Change of Baseline Toxicity in Wastewater Spiked with Organic Micro-pollutants

    KAUST Repository

    Gan, Alexander

    2012-07-01

    Bioassays for baseline toxicity, which measure toxicants’ non-specific effects, have been shown in previous studies to effectively correlate with the increased presence of pharmaceuticals, personal care products, endocrine-disrupting compounds, and other synthetic organics in treated sewage effluent. This study investigated how the baseline toxicity of anthropogenic compounds-spiked wastewater changed during the treatment of biofiltration and ozone oxidation, as measured by the bioluminescence inhibition of the Vibrio fischeri bacterium. The water quality parameters of dissolved organic carbon, seven common anions, and fluorescence spectroscopy were used to corroborate and collate with the toxicity results. Water quality was evaluated on two bench-scale soil filtration columns, which were configured for pre-ozonation and post-ozonation. Both systems’ soil aerobically removed similar amounts of dissolved organic carbon, and the reduction ranged between 57.7% and 62.1% for the post-ozonation and pre-ozonation systems, respectively. Biological removal of DOC, protein-like, humic-like, and soluble microbial product-like material was highest in the first 28.5 cm of each 114 cm-long system. While bioluminescence inhibition showed that ozonation was effective at lowering baseline toxicity, this study’s bioassay procedure was a very poor indicator of soil filtration treatment; both system’s effluents were significantly more toxic than their non-ozonated influents.

  9. Toxic effect of a marine bacterium on aquatic organisms and its algicidal substances against Phaeocystis globosa.

    Directory of Open Access Journals (Sweden)

    Qiuchan Yang

    Full Text Available Harmful algal blooms have caused enormous damage to the marine ecosystem and the coastal economy in China. In this paper, a bacterial strain B1, which had strong algicidal activity against Phaeocystis globosa, was isolated from the coastal waters of Zhuhai in China. The strain B1 was identified as Bacillus sp. on the basis of 16S rDNA gene sequence and morphological characteristics. To evaluate the ecological safety of the algicidal substances produced by strain B1, their toxic effects on marine organisms were tested. Results showed that there were no adverse effects observed in the growth of Chlorella vulgaris, Chaetoceros muelleri, and Isochrystis galbana after exposure to the algicidal substances at a concentration of 1.0% (v/v for 96 h. The 48h LC50 values for Brachionus plicatilis, Moina mongolica Daday and Paralichthys olivaceus were 5.7, 9.0 and 12.1% (v/v, respectively. Subsequently, the algicidal substances from strain B1 culture were isolated and purified by silica gel column, Sephadex G-15 column and high-performance liquid chromatography. Based on quadrupole time-of-flight mass spectrometry and PeakView Software, the purified substances were identified as prolyl-methionine and hypoxanthine. Algicidal mechanism indicated that prolyl-methionine and hypoxanthine inhibited the growth of P. globosa by disrupting the antioxidant systems. In the acute toxicity assessment using M. mongolica, 24h LC50 values of prolyl-methionine and hypoxanthine were 7.0 and 13.8 g/L, respectively. The active substances produced by strain B1 can be considered as ecologically and environmentally biological agents for controlling harmful algal blooms.

  10. The acute toxicity of thallium to freshwater organisms: Implications for risk assessment.

    Science.gov (United States)

    Tatsi, Kristi; Turner, Andrew; Handy, Richard D; Shaw, Benjamin J

    2015-12-01

    The acute toxicity of Tl(I) to the microalga, Pseudokirchneriella subcapitata, the planktonic crustaceans, Daphnia magna and Daphnia pulex, and early-life stage of the zebrafish, Danio rerio, has been studied according to OECD protocols. Toxicological end-point concentrations for the microalga ranged from 17 μg l(-1) for a 72 h EyC25 (yield inhibition) to 80 μg l(-1) for a 72 h ErC50 (growth inhibition). Daphnia were less sensitive to Tl, with 48 h EC50s of about 1000 μg l(-1) and 1200 μg l(-1) for D. magna and D. pulex, respectively; however, end-point concentrations were reduced considerably (to about 510 μg l(-1) and 730 μg l(-1), respectively) when experiments were repeated in dechlorinated Plymouth tap water (rather than OECD medium). The 96 h LC50 for D. rerio was 870 μg l(-1) but a variety of sub-lethal effects, including enlargement of yolk sac and reduction in heart beat rate, were observed when larvae were exposed to lower concentrations. Based on these results, a predicted no effect concentration (PNEC) for Tl in freshwaters of 0.087 μg l(-1) is proposed. The PNEC is an order of magnitude lower than the only (Canadian) water quality guideline for Tl that appears to exist, and is lower than Tl concentrations reported in freshwaters impacted by historical or contemporary metal mining. Our results are also consistent with previous studies that employ different organisms and end-points in that Tl toxicity is dependent on the concentration of K+, the biogeochemical analogue of Tl+. Accordingly, regulation of Tl in the freshwater environment should factor in the relative abundance of K. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Cometary Dust

    Science.gov (United States)

    Levasseur-Regourd, Anny-Chantal; Agarwal, Jessica; Cottin, Hervé; Engrand, Cécile; Flynn, George; Fulle, Marco; Gombosi, Tamas; Langevin, Yves; Lasue, Jérémie; Mannel, Thurid; Merouane, Sihane; Poch, Olivier; Thomas, Nicolas; Westphal, Andrew

    2018-04-01

    This review presents our understanding of cometary dust at the end of 2017. For decades, insight about the dust ejected by nuclei of comets had stemmed from remote observations from Earth or Earth's orbit, and from flybys, including the samples of dust returned to Earth for laboratory studies by the Stardust return capsule. The long-duration Rosetta mission has recently provided a huge and unique amount of data, obtained using numerous instruments, including innovative dust instruments, over a wide range of distances from the Sun and from the nucleus. The diverse approaches available to study dust in comets, together with the related theoretical and experimental studies, provide evidence of the composition and physical properties of dust particles, e.g., the presence of a large fraction of carbon in macromolecules, and of aggregates on a wide range of scales. The results have opened vivid discussions on the variety of dust-release processes and on the diversity of dust properties in comets, as well as on the formation of cometary dust, and on its presence in the near-Earth interplanetary medium. These discussions stress the significance of future explorations as a way to decipher the formation and evolution of our Solar System.

  12. Emissions of organic air toxics from open burning: a comprehensive review

    Energy Technology Data Exchange (ETDEWEB)

    Lemieux, P M [United States Environmental Protection Agency, NC (United States). Air Pollution Prevention and Control Division, National Risk Management Research Laboratory; Lutes, C C; Santoianni, D A [ARCADIS G and M, Durham, NC (United States)

    2004-07-01

    Emissions from open burning, on a mass pollutant per mass fuel (emission factor) basis, are greater than those from well-controlled combustion sources. Some types of open burning (e.g. biomass) are large sources on a global scale in comparison to other broad classes of sources (e.g. mobile and industrial sources). A detailed literature search was performed to collect and collate available data reporting emissions of organic air toxics from open burning sources. The sources that were included in this paper are: Accidental Fires, Agricultural Burning of Crop Residue, Agricultural Plastic Film, Animal Carcasses, Automobile Shredder Fluff Fires, Camp Fires, Car-Boat-Train (the vehicle not cargo) Fires, Construction Debris Fires, Copper Wire Reclamation, Crude Oil and Oil Spill Fires, Electronics Waste, Fiberglass, Fireworks, Grain Silo Fires, Household Waste, Land Clearing Debris (biomass), Landfills/Dumps, Prescribed Burning and Savanna/Forest Fires, Structural Fires, Tire Fires, and Yard Waste Fires. Availability of data varied according to the source and the class of air toxics of interest. Volatile organic compound (VOC) and polycyclic aromatic hydrocarbon (PAH) data were available for many of the sources. Non-PAH semi-volatile organic compound (SVOC) data were available for several sources. Carbonyl and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofuran (PCDD/F) data were available for only a few sources. There were several known sources for which no emissions data were available at all. It is desirable that emissions from those sources be tested so that the relative degree of hazard they pose can be assessed. Several observations were made including: Biomass open burning sources typically emitted less VOCs than open burning sources with anthropogenic fuels on a mass emitted per mass burned basis, particularly those where polymers were concerned. Biomass open burning sources typically emitted less SVOCs and PAHs than anthropogenic sources on a mass

  13. High-Density Real-Time PCR-Based in Vivo Toxicogenomic Screen to Predict Organ-Specific Toxicity

    Directory of Open Access Journals (Sweden)

    Laszlo G. Puskas

    2011-09-01

    Full Text Available Toxicogenomics, based on the temporal effects of drugs on gene expression, is able to predict toxic effects earlier than traditional technologies by analyzing changes in genomic biomarkers that could precede subsequent protein translation and initiation of histological organ damage. In the present study our objective was to extend in vivo toxicogenomic screening from analyzing one or a few tissues to multiple organs, including heart, kidney, brain, liver and spleen. Nanocapillary quantitative real-time PCR (QRT-PCR was used in the study, due to its higher throughput, sensitivity and reproducibility, and larger dynamic range compared to DNA microarray technologies. Based on previous data, 56 gene markers were selected coding for proteins with different functions, such as proteins for acute phase response, inflammation, oxidative stress, metabolic processes, heat-shock response, cell cycle/apoptosis regulation and enzymes which are involved in detoxification. Some of the marker genes are specific to certain organs, and some of them are general indicators of toxicity in multiple organs. Utility of the nanocapillary QRT-PCR platform was demonstrated by screening different references, as well as discovery of drug-like compounds for their gene expression profiles in different organs of treated mice in an acute experiment. For each compound, 896 QRT-PCR were done: four organs were used from each of the treated four animals to monitor the relative expression of 56 genes. Based on expression data of the discovery gene set of toxicology biomarkers the cardio- and nephrotoxicity of doxorubicin and sulfasalazin, the hepato- and nephrotoxicity of rotenone, dihydrocoumarin and aniline, and the liver toxicity of 2,4-diaminotoluene could be confirmed. The acute heart and kidney toxicity of the active metabolite SN-38 from its less toxic prodrug, irinotecan could be differentiated, and two novel gene markers for hormone replacement therapy were identified

  14. Characterization of organic matter in dusts and fluvial sediments from exposed areas of dowtown Prague, Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Sýkorová, Ivana; Havelcová, Martina; Trejtnarová, Hana; Matysová, Petra; Vašíček, Michal; Suchý, V.; Kříbek, B.

    2009-01-01

    Roč. 80, č. 2 (2009), s. 69-86 ISSN 0166-5162 R&D Projects: GA AV ČR IAA300460804 Institutional research plan: CEZ:AV0Z30460519 Keywords : dust * fluvial sediment * carbonaceous particles Subject RIV: DD - Geochemistry Impact factor: 1.924, year: 2009

  15. Valorization of GaN based metal-organic chemical vapor deposition dust a semiconductor power device industry waste through mechanochemical oxidation and leaching: A sustainable green process

    Energy Technology Data Exchange (ETDEWEB)

    Swain, Basudev, E-mail: Swain@iae.re.kr [Institute for Advanced Engineering (IAE), Advanced Materials & Processing Center, Yongin-Si 449-863 (Korea, Republic of); Mishra, Chinmayee; Lee, Chan Gi; Park, Kyung-Soo [Institute for Advanced Engineering (IAE), Advanced Materials & Processing Center, Yongin-Si 449-863 (Korea, Republic of); Lee, Kun-Jae [Department of Energy Engineering, Dankook University, Cheonan 330-714 (Korea, Republic of)

    2015-07-15

    Dust generated during metal organic vapor deposition (MOCVD) process of GaN based semiconductor power device industry contains significant amounts of gallium and indium. These semiconductor power device industry wastes contain gallium as GaN and Ga{sub 0.97}N{sub 0.9}O{sub 0.09} is a concern for the environment which can add value through recycling. In the present study, this waste is recycled through mechanochemical oxidation and leaching. For quantitative recovery of gallium, two different mechanochemical oxidation leaching process flow sheets are proposed. In one process, first the Ga{sub 0.97}N{sub 0.9}O{sub 0.09} of the MOCVD dust is leached at the optimum condition. Subsequently, the leach residue is mechanochemically treated, followed by oxidative annealing and finally re-leached. In the second process, the MOCVD waste dust is mechanochemically treated, followed by oxidative annealing and finally leached. Both of these treatment processes are competitive with each other, appropriate for gallium leaching and treatment of the waste MOCVD dust. Without mechanochemical oxidation, 40.11 and 1.86 w/w% of gallium and Indium are leached using 4 M HCl, 100 °C and pulp density of 100 kg/m{sup 3,} respectively. After mechanochemical oxidation, both these processes achieved 90 w/w% of gallium and 1.86 w/w% of indium leaching at their optimum condition. - Highlights: • Waste MOCVD dust is treated through mechanochemical leaching. • GaN is hardly leached, and converted to NaGaO{sub 2} through ball milling and annealing. • Process for gallium recovery from waste MOCVD dust has been developed. • Thermal analysis and phase properties of GaN to Ga{sub 2}O{sub 3} and GaN to NaGaO{sub 2} is revealed. • Solid-state chemistry involved in this process is reported.

  16. Bioaccumulation and Toxicity of Single-Walled Carbon Nanotubes to Benthic Organisms at the Base of the Marine Food Chain

    Science.gov (United States)

    As the use of single-walled carbon nanotubes (SWNTs) increases over time, so does the potential for environmental release. This research aimed to determine the toxicity, bioavailability, and bioaccumulation of SWNTs in marine benthic organisms at the base of the food chain. The t...

  17. INTERSPECIES CORRELATION ESTIMATION (ICE) FOR ACUTE TOXICITY TO AQUATIC ORGANISMS AND WILDLIFE. II. USER MANUAL AND SOFTWARE

    Science.gov (United States)

    Asfaw, Amha, Mark R. Ellersieck and Foster L. Mayer. 2003. Interspecies Correlation Estimations (ICE) for Acute Toxicity to Aquatic Organisms and Wildlife. II. User Manual and Software. EPA/600/R-03/106. U.S. Environmental Protection Agency, National Health and Environmental Effe...

  18. Individual and combined effects of organic, toxic, and hydraulic shocks on sequencing batch reactor in treating petroleum refinery wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Mizzouri, Nashwan Sh., E-mail: nashwan_mizzouri@yahoo.com [Department of Civil Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia); Department of Civil Engineering, University of Duhok, Kurdistan (Iraq); Shaaban, Md Ghazaly [Department of Civil Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia)

    2013-04-15

    Highlights: ► This research focuses on the combined impact of shock loads on the PRWW treatment. ► System failure resulted when combined shock of organic and hydraulic was applied. ► Recovery was achieved by replacing glucose with PRWW and OLR was decreased to half. ► Worst COD removals were 68.9, and 57.8% for organic, and combined shocks. -- Abstract: This study analyzes the effects of toxic, hydraulic, and organic shocks on the performance of a lab-scale sequencing batch reactor (SBR) with a capacity of 5 L. Petroleum refinery wastewater (PRWW) was treated with an organic loading rate (OLR) of approximately 0.3 kg chemical oxygen demand (COD)/kg MLSS d at 12.8 h hydraulic retention time (HRT). A considerable variation in the COD was observed for organic, toxic, hydraulic, and combined shocks, and the worst values observed were 68.9, 77.1, 70.2, and 57.8%, respectively. Improved control of toxic shock loads of 10 and 20 mg/L of chromium (VI) was identified. The system was adversely affected by the organic shock when a shock load thrice the normal value was used, and this behavior was repeated when the hydraulic shock was 4.8 h HRT. The empirical recovery period was greater than the theoretical period because of the inhibitory effects of phenols, sulfides, high oil, and grease in the PRWW. The system recovery rates from the shocks were in the following order: toxic, organic, hydraulic, and combined shocks. System failure occurred when the combined shocks of organic and hydraulic were applied. The system was resumed by replacing the PRWW with glucose, and the OLR was reduced to half its initial value.

  19. Resolving the false-negative issues of the nonpolar organic amendment in whole-sediment toxicity identification evaluations.

    Science.gov (United States)

    Mehler, W Tyler; Keough, Michael J; Pettigrove, Vincent

    2018-04-01

    Three common false-negative scenarios have been encountered with amendment addition in whole-sediment toxicity identification evaluations (TIEs): dilution of toxicity by amendment addition (i.e., not toxic enough), not enough amendment present to reduce toxicity (i.e., too toxic), and the amendment itself elicits a toxic response (i.e., secondary amendment effect). One such amendment in which all 3 types of false-negatives have been observed is with the nonpolar organic amendment (activated carbon or powdered coconut charcoal). The objective of the present study was to reduce the likelihood of encountering false-negatives with this amendment and to increase the value of the whole-sediment TIE bioassay. To do this, the present study evaluated the effects of various activated carbon additions to survival, growth, emergence, and mean development rate of Chironomus tepperi. Using this information, an alternative method for this amendment was developed which utilized a combination of multiple amendment addition ratios based on wet weight (1%, lower likelihood of the secondary amendment effect; 5%, higher reduction of contaminant) and nonconventional endpoints (emergence, mean development rate). This alternative method was then validated in the laboratory (using spiked sediments) and with contaminated field sediments. Using these multiple activated carbon ratios in combination with additional endpoints (namely, emergence) reduced the likelihood of all 3 types of false-negatives and provided a more sensitive evaluation of risk. Environ Toxicol Chem 2018;37:1219-1230. © 2017 SETAC. © 2017 SETAC.

  20. Diuron exposure induces systemic and organ-specific toxicity following acute and sub-chronic exposure in male Wistar rats.

    Science.gov (United States)

    Domingues, Alexandre; Barbisan, Luis Fernando; Martins, Priscila Raquel; Spinardi-Barbisan, Ana Lúcia Tozzi

    2011-05-01

    Diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] is a substitute urea herbicide widely used on agricultural crops with potential mutagenic, teratogenic, reproductive and carcinogenic effects. Nonetheless, its toxic potential on the immune system needs a detailed assessment. Thus, in order to evaluate the adverse effect of this herbicide on lymphohematopoietic organs and macrophage activity, male Wistar rats were orally treated with Diuron at 125, 1250 and 2500 ppm for 14, 28 or 90 days. General signs of toxicity were observed in Diuron-treated groups (1250 and 2500 ppm), including reduced food intake and body weight gain, as well as higher relative weights for spleen, kidneys and liver (28 and 90-day toxicity studies) and elevated serum levels of ALT, albumin, total protein, creatinine and urea (28-day toxicity study). Diuron exposure caused a severe depletion of splenic white pulp compartments and cellularity, followed by a decreased number of CD4(+) T lymphocytes, increased extramedullary hematopoiesis and deposition of hemosiderin in red pulp. Despite alteration in macrophage spreading, the macrophagic activity was not significantly affected by the herbicide. Under these experimental conditions, the results suggest that Diuron exerts systemic and target-organ toxicity, mainly at higher concentration. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Occurrence and risk assessment of potentially toxic elements and typical organic pollutants in contaminated rural soils.

    Science.gov (United States)

    Xu, Yongfeng; Dai, Shixiang; Meng, Ke; Wang, Yuting; Ren, Wenjie; Zhao, Ling; Christie, Peter; Teng, Ying

    2018-07-15

    The residual levels and risk assessment of several potentially toxic elements (PTEs), phthalate esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs) in rural soils near different types of pollution sources in Tianjin, China, were studied. The soils were found to be polluted to different extents with PTEs, PAEs and PAHs from different pollution sources. The soil concentrations of chromium (Cr), nickel (Ni), di-n-butyl phthalate (DnBP), acenaphthylene (Any) and acenaphthene (Ane) were higher than their corresponding regulatory reference limits. The health risk assessment model used to calculate human exposure indicates that both non-carcinogenic and carcinogenic risks from selected pollutants were generally acceptable or close to acceptable. Different types of pollution sources and soil physicochemical properties substantially affected the soil residual concentrations of and risks from these pollutants. PTEs in soils collected from agricultural lands around industrial and residential areas and organic pollutants (PAEs and PAHs) in soils collected from agricultural areas around livestock breeding were higher than those from other types of pollution sources and merit long-term monitoring. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Growth of eucalyptus rooted cuttings in toxic organic waste compost of textile industry

    Directory of Open Access Journals (Sweden)

    Priscila F. de Souza

    2015-09-01

    Full Text Available ABSTRACTBiodegradation techniques may help contaminated organic wastes to become useful for plant production. The current study aimed to evaluate the efficiency of composting in the biodegradation of toxic residues from the textile industry and its use as substrate in saplings production. Cotton cloths contaminated with oil and grease, used in loom maintenance, were composted in a mixture with cattle manure. The composted material replaced coconut fiber in the substrate for the production of eucalyptus rooted cuttings: mixture of vermiculite, carbonized rice husk and coconut fiber in the ratio of 2:1:1 (v/v and using it as control. Thus, the amount of rice husks remained unchanged and the amount of vermiculite and compost varied. The compost proportion in the tested substrates were 0, 19, 37, 56 and 75%. The compost produced from textile wastes showed high nutrient levels and low levels of heavy metals. In general, the survival, growth and some growth indices of rooted cuttings produced on substrates with 19 and 37% compost were similar to those of rooted cuttings grown in commercial substrate. Composting is efficient and the material is useful for rooted cuttings production.

  3. Maintenance of adult primate liver in organ culture: Potential use in toxicity testing

    International Nuclear Information System (INIS)

    Smith, P.F.; O'Brien, K.A.; Allen, L.; DeLuca, J.; Norman, B.; Keenan, K.P.

    1991-01-01

    Adult Rhesus monkey liver slices were incubated using a dynamic organ culture method to determine hepatocyte viability, drug biotransformation potential and the in vitro response to the hepatotoxicant, allyl alcohol (AA). After 1, 2, 4, or 8 hr, slices were removed from culture and analyzed for incorporation of [ 3 H]-leucine into acid-precipitable material, and medium alanine aminotransferase (ALT) activity was determined. Separate slices were taken for histological evaluation and for evaluation of microsomal 7-ethoxy-4-trifluoromethyl coumarin-O-deethylase (EFCOD) activity. Incorporation of [ 3 H]-leucine into slices was linear over the period of incubation and was specifically inhibited by cycloheximide (10 uM) at all time points. In the absence of AA, enzyme leakage was minimal over 8 hr. Marked ALT leakage occurred with 1 mM AA. Control slices had an initial fall to 55% of in vivo EFCOD activity that stabilized at 40-50% control slices indicated that there was minimal cellular degeneration and that, in PAS-stained sections, glycogen accumulation occurred over the incubation period. This system allows for maintenance and viability of adult primate liver slices in culture for at least 8 hr and may be useful for in vitro toxicity and biotransformation studies

  4. [Optimization of solid-phase extraction for enrichment of toxic organic compounds in water samples].

    Science.gov (United States)

    Zhang, Ming-quan; Li, Feng-min; Wu, Qian-yuan; Hu, Hong-ying

    2013-05-01

    A concentration method for enrichment of toxic organic compounds in water samples has been developed based on combined solid-phase extraction (SPE) to reduce impurities and improve recoveries of target compounds. This SPE method was evaluated in every stage to identify the source of impurities. Based on the analysis of Waters Oasis HLB without water samples, the eluent of SPE sorbent after dichloromethane and acetone contributed 85% of impurities during SPE process. In order to reduce the impurities from SPE sorbent, soxhlet extraction of dichloromethane followed by acetone and lastly methanol was applied to the sorbents for 24 hours and the results had proven that impurities were reduced significantly. In addition to soxhlet extraction, six types of prevalent SPE sorbents were used to absorb 40 target compounds, the lgK(ow) values of which were within the range of 1.46 and 8.1, and recovery rates were compared. It was noticed and confirmed that Waters Oasis HLB had shown the best recovery results for most of the common testing samples among all three styrenedivinylbenzene (SDB) polymer sorbents, which were 77% on average. Furthermore, Waters SepPak AC-2 provided good recovery results for pesticides among three types of activated carbon sorbents and the average recovery rates reached 74%. Therefore, Waters Oasis HLB and Waters SepPak AC-2 were combined to obtain a better recovery and the average recovery rate for the tested 40 compounds of this new SPE method was 87%.

  5. New land disposal restrictions on contaminated soil and debris, and newly identified toxicity characteristic organics

    International Nuclear Information System (INIS)

    Fortune, William B.; Schumann, Jean C.; Fallon, William E.; Badden, Janet W.; Smith, Edward H.

    1992-01-01

    The applicability of the Resource Conservation and Recovery Act (RCRA) Land Disposal Restrictions (LDR) program to radioactive mixed wastes (RMW) has been clarified through U.S. Environmental Protection Agency (EPA) and U.S. Department of Energy (DOE) rulemakings and notices. However, a number of waste management concerns involving RMW and RMW-contaminated soil and debris continue to exist with respect to achieving compliance with LDR provisions and treatment standards. Consequently, DOE has become increasingly proactive in its participation in the LDR rulemaking process and in the identification of LDR compliance issues associated with its RMW inventories. Both data and recommendations from across the DOE complex were collected and transmitted to EPA in response to proposed requirements that would implement LDR for contaminated soil and debris, and certain newly identified toxicity characteristic (TC) organics. Much of this information focused on concerns related to the application of proposed regulatory approaches to RMW streams. Highlights from the information included in these DOE responses are presented. (author)

  6. Trichloroethylene Biotransformation and its Role in Mutagenicity, Carcinogenicity and Target Organ Toxicity

    Science.gov (United States)

    Lash, Lawrence H.; Chiu, Weihsueh A.; Guyton, Kathryn Z.; Rusyn, Ivan

    2014-01-01

    Metabolism is critical for the mutagenicity, carcinogenicity, and other adverse health effects of trichloroethylene (TCE). Despite the relatively small size and simple chemical structure of TCE, its metabolism is quite complex, yielding multiple intermediates and end-products. Experimental animal and human data indicate that TCE metabolism occurs through two major pathways: cytochrome P450 (CYP)-dependent oxidation and glutathione (GSH) conjugation catalyzed by GSH S-transferases (GSTs). Herein we review recent data characterizing TCE processing and flux through these pathways. We describe the catalytic enzymes, their regulation and tissue localization, as well as the evidence for transport and inter-organ processing of metabolites. We address the chemical reactivity of TCE metabolites, highlighting data on mutagenicity of these end-products. Identification in urine of key metabolites, particularly trichloroacetate (TCA), dichloroacetate (DCA), trichloroethanol and its glucuronide (TCOH and TCOG), and N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine (NAcDCVC), in exposed humans and other species (mostly rats and mice) demonstrates function of the two metabolic pathways in vivo. The CYP pathway primarily yields chemically stable end-products. However, the GST pathway conjugate S-(1,2-dichlorovinyl)glutathione (DCVG) is further processed to multiple highly reactive species that are known to be mutagenic, especially in kidney where in situ metabolism occurs. TCE metabolism is highly variable across sexes, species, tissues and individuals. Genetic polymorphisms in several of the key enzymes metabolizing TCE and its intermediates contribute to variability in metabolic profiles and rates. In all, the evidence characterizing the complex metabolism of TCE can inform predictions of adverse responses including mutagenesis, carcinogenesis, and acute and chronic organ-specific toxicity. PMID:25484616

  7. Volatile organic compounds emitted by filamentous fungi isolated from flooded homes after Hurricane Sandy show toxicity in a Drosophila bioassay.

    Science.gov (United States)

    Zhao, G; Yin, G; Inamdar, A A; Luo, J; Zhang, N; Yang, I; Buckley, B; Bennett, J W

    2017-05-01

    Superstorm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to eight genera: Penicillium (11 species), Fusarium (four species), Aspergillus (three species), Trichoderma (two species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis. Then, we used a Drosophila larval assay to assess possible toxicity of volatile organic compounds (VOCs) emitted by these molds. When cultured in a shared atmosphere with growing cultures of molds isolated after Hurricane Sandy, larval toxicity ranged from 15 to 80%. VOCs from Aspergillus niger 129B were the most toxic yielding 80% mortality to Drosophila after 12 days. The VOCs from Trichoderma longibrachiatum 117, Mucor racemosus 138a, and Metarhizium anisopliae 124 were relatively non-toxigenic. A preliminary analysis of VOCs was conducted using solid-phase microextraction-gas chromatography-mass spectrometry from two of the most toxic, two of the least toxic, and two species of intermediate toxicity. The more toxic molds produced higher concentrations of 1-octen-3-ol, 3-octanone, 3-octanol, 2-octen-1-ol, and 2-nonanone; while the less toxic molds produced more 3-methyl-1-butanol and 2-methyl-1-propanol, or an overall lower amount of volatiles. Our data support the hypothesis that at certain concentrations, some VOCs emitted by indoor molds are toxigenic. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Exposure to grain dust in Great Britain.

    Science.gov (United States)

    Spankie, Sally; Cherrie, John W

    2012-01-01

    Airborne grain dust is a complex mixture of fragments of organic material from grain, plus mineral matter from soil, and possible insect, fungal, or bacterial contamination or their toxic products, such as endotoxin. In the 1990s, grain workers in Britain were frequently exposed to inhalable dust >10 mg.m(-3) (8 h), with particularly high exposures being found at terminals where grain was imported or exported and in drying operations (personal exposure typically approximately 20 mg.m(-3)). Since then, the industry has made substantial progress in improving the control of airborne dust through better-designed processes, increased automation, and an improved focus on product quality. We have used information from the published scientific literature and a small survey of industry representatives to estimate current exposure levels. These data suggest that current long-term exposure to inhalable dust for most workers is on average less than approximately 3 mg.m(-3), with perhaps 15-20% of individual personal exposures being >10 mg.m(-3). There are no published data from Britain on short-term exposure during cleaning and other tasks. We have estimated average levels for a range of tasks and judge that the highest levels, for example during some cleaning activities and certain process tasks such as loading and packing, are probably approximately10 mg.m(-3). Endotoxin levels were judged likely to be dust levels are <10 mg.m(-3). There are no published exposure data on mycotoxin, respirable crystalline silica, and mite contamination but these are not considered to present widespread problems in the British industry. Further research should be carried out to confirm these findings.

  9. Target organ specific activity of drosophila MRP (ABCC1) moderates developmental toxicity of methylmercury.

    Science.gov (United States)

    Prince, Lisa; Korbas, Malgorzata; Davidson, Philip; Broberg, Karin; Rand, Matthew Dearborn

    2014-08-01

    Methylmercury (MeHg) is a ubiquitous and persistent neurotoxin that poses a risk to human health. Although the mechanisms of MeHg toxicity are not fully understood, factors that contribute to susceptibility are even less well known. Studies of human gene polymorphisms have identified a potential role for the multidrug resistance-like protein (MRP/ABCC) family, ATP-dependent transporters, in MeHg susceptibility. MRP transporters have been shown to be important for MeHg excretion in adult mouse models, but their role in moderating MeHg toxicity during development has not been explored. We therefore investigated effects of manipulating expression levels of MRP using a Drosophila development assay. Drosophila MRP (dMRP) is homologous to human MRP1-4 (ABCC1-4), sharing 50% identity and 67% similarity with MRP1. A greater susceptibility to MeHg is seen in dMRP mutant flies, demonstrated by reduced rates of eclosion on MeHg-containing food. Furthermore, targeted knockdown of dMRP expression using GAL4>UAS RNAi methods demonstrates a tissue-specific function for dMRP in gut, Malpighian tubules, and the nervous system in moderating developmental susceptibility to MeHg. Using X-ray synchrotron fluorescence imaging, these same tissues were also identified as the highest Hg-accumulating tissues in fly larvae. Moreover, higher levels of Hg are seen in dMRP mutant larvae compared with a control strain fed an equivalent dose of MeHg. In sum, these data demonstrate that dMRP expression, both globally and within Hg-targeted organs, has a profound effect on susceptibility to MeHg in developing flies. Our findings point to a potentially novel and specific role for dMRP in neurons in the protection against MeHg. Finally, this experimental system provides a tractable model to evaluate human polymorphic variants of MRP and other gene variants relevant to genetic studies of mercury-exposed populations. © The Author 2014. Published by Oxford University Press on behalf of the Society of

  10. Treatment of toxic and hazardous organic wastes by wet oxidation process with oxygenated water at low temperature

    International Nuclear Information System (INIS)

    Piccinno, T.; Salluzzo, A.; Nardi, L.; Gili, M.; Luce, A.; Troiani, F.; Cornacchia, G.

    1989-11-01

    The wet oxidation process using air or molecular oxygen is a well-known process from long time. It is suitable to oxidize several types of waste refractory to the usual biological, thermal and chemical treatments. The drastic operating conditions (high pressures and temperatures) prevented its industrial development. In the last years a new interest was assigned to the process for the treatment of nuclear wastes (organic resins and exhaust organic wastes); the treatment is carried out at widely reduced operating conditions (atmospheric pressure and boiling temperature) by means of metallic catalysts and hydrogen peroxide. With some limits, the wet oxidation with hydrogen peroxide at low temperature can be applied to conventional waste waters containing toxic organic compounds. In the present report are summarized the activities developed at ENEA Fuel Cycle Department by the task force 'Deox' constituted by laboratory and plant specialists in order to verify the application of the wet oxidation process to the treatment of the toxic wastes. (author)

  11. Allergies, asthma, and dust

    Science.gov (United States)

    Reactive airway disease - dust; Bronchial asthma - dust; Triggers - dust ... Things that make allergies or asthma worse are called triggers. Dust is a common trigger. When your asthma or allergies become worse due to dust, you are ...

  12. Genotoxicity and carcinogenicity of diesel soot and oil shale dust, two markedly different particles with associated organic content

    International Nuclear Information System (INIS)

    Mauderly, J.L.; Barr, E.B.; Bechtold, W.E.

    1987-01-01

    Levels of DNA adducts in lungs of rats were measured by 32 P postlabeling techniques after 240-mo exposure to either diesel exhaust or oil shale dusts. Preliminary results suggest that whole-lung adduct levels from chronic inhalation exposures are not predictive for carcinogenicity. Lung tumors were observed in animals exposed to diesel exhaust. Carcinogenicity was correlated to the mutagenicity of extracts and severity of epithelial proliferation

  13. Dust, Climate, and Human Health

    Science.gov (United States)

    Maynard, Nancy G.

    2003-01-01

    Air pollution from both natural and anthropogenic causes is considered to be one of the most serious world-wide environment-related health problems, and is expected to become worse with changes in the global climate. Dust storms from the atmospheric transport of desert soil dust that has been lifted and carried by the winds - often over significant distances - have become an increasingly important emerging air quality issue for many populations. Recent studies have shown that the dust storms can cause significant health impacts from the dust itself as well as the accompanying pollutants, pesticides, metals, salt, plant debris, and other inorganic and organic materials, including viable microorganisms (bacteria, viruses and fungi). For example, thousands of tons of Asian desert sediments, some containing pesticides and herbicides from farming regions, are commonly transported into the Arctic during dust storm events. These chemicals have been identified in animal and human tissues among Arctic indigenous populations. Millions of tons of airborne desert dust are being tracked by satellite imagery, which clearly shows the magnitude as well as the temporal and spatial variability of dust storms across the "dust belt" regions of North Africa, the Middle East, and China. This paper summarizes the most recent findings on the effects of airborne desert dust on human health as well as potential climate influences on dust and health.

  14. Trace metals in urban road dust

    International Nuclear Information System (INIS)

    Randazzo, Loredana Antonella; Dongarra, Gaetano; Manno, Emanuela; Varrica, Daniela

    2006-01-01

    Heavy metals associated with urban road dust is a matter for concern as they may have serious effects on biological systems. The bioavailability and potential toxicity of metals bound to urban dust is related to the specific chemical form of the element. In the present article are reported the determinations and chemical speciation of As, Ba, Cr, Cu, Mo, Ni, Pb and Zn in six samples of road dust collected within the urban centre and the outskirts of Palermo [it

  15. Dust collected in air filters - Possible source of volatile organic compounds and particles; Ger smutsiga luftfilter foersaemrad tilluft ? En studie av emissioner med ursprung i filter

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, J.H.P.; Rosell, Lars

    1998-06-01

    Emissions from dust collected in air filters have been investigated using in situ measurements. Two air filters of different classes (F6 and F8/9) have been exposed to outdoor air for a preconditioning period of six months. After this period measurements have been carried out using two operating conditions, continuous and intermittent. Air samples were taken both up- and downstream of the filters. The air samples were analysed regarding volatile organic compounds (VOCs), including formaldehyde and microbial VOCs (mVOC) and the samples of airborne dust were examined regarding the contents of colony forming units, ergosterol (marker of fungi), and endotoxin (marker of gram negative bacteria). Furthermore, a visual inspection of the airborne dust was conducted using SEM. Particles released when the fan was turned on and a short period after, were monitored using an optical particle counter, slitsamplers (fungus spores) and membrane filters for SEM analysis. After finishing the in situ measurements, the filters were placed in climate chambers for emission sampling. Finally, samples were cut out for analysis of microbial contents in the filter material, both on the dusty and `clean` side of the filters. No consistent change of VOC, aldehyde or mVOC concentrations across the filters could be measured. A significant ozone reduction was seen in one of the in situ measurements. The chamber experiments showed that the filters were a source of various VOCs, e.g. aldehydes and mVOCs. The emission of mVOCs in the chambers was significantly higher for the F8/9 filter, probably due to more and finer dust in that filter. Only a few colonization units (fungi) penetrate filters when running continuously but an increase was noted at the moment the fans were started. The same phenomenon was observed with the optical particle counter, but both the intensity and length of the increase, for colonization units and other particles, were moderate. Mycological examination of the filter

  16. Role of the plasma membrane H+-ATPase in the regulation of organic acid exudation under aluminum toxicity and phosphorus deficiency

    Science.gov (United States)

    Yu, Wenqian; Kan, Qi; Zhang, Jiarong; Zeng, Bingjie; Chen, Qi

    2016-01-01

    Aluminum (Al) toxicity and phosphorus (P) deficiency are 2 major limiting factors for plant growth and crop production in acidic soils. Organic acids exuded from roots have been generally regarded as a major resistance mechanism to Al toxicity and P deficiency. The exudation of organic acids is mediated by membrane-localized OA transporters, such as ALMT (Al-activated malate transporter) and MATE (multidrug and toxic compound extrusion). Beside on up-regulation expression of organic acids transporter gene, transcriptional, translational and post-translational regulation of the plasma membrane H+-ATPase are also involved in organic acid release process under Al toxicity and P deficiency. This mini-review summarizes the current knowledge about this field of study on the role of the plasma membrane H+-ATPase in organic acid exudation under Al toxicity and P deficiency conditions. PMID:26713714

  17. Role of the plasma membrane H(+)-ATPase in the regulation of organic acid exudation under aluminum toxicity and phosphorus deficiency.

    Science.gov (United States)

    Yu, Wenqian; Kan, Qi; Zhang, Jiarong; Zeng, Bingjie; Chen, Qi

    2016-01-01

    Aluminum (Al) toxicity and phosphorus (P) deficiency are 2 major limiting factors for plant growth and crop production in acidic soils. Organic acids exuded from roots have been generally regarded as a major resistance mechanism to Al toxicity and P deficiency. The exudation of organic acids is mediated by membrane-localized OA transporters, such as ALMT (Al-activated malate transporter) and MATE (multidrug and toxic compound extrusion). Beside on up-regulation expression of organic acids transporter gene, transcriptional, translational and post-translational regulation of the plasma membrane H(+)-ATPase are also involved in organic acid release process under Al toxicity and P deficiency. This mini-review summarizes the current knowledge about this field of study on the role of the plasma membrane H(+)-ATPase in organic acid exudation under Al toxicity and P deficiency conditions.

  18. Synthesis and toxicity evaluation of hydrophobic ionic liquids for volatile organic compounds biodegradation in a two-phase partitioning bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Castillo, Alfredo Santiago [Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7 (France); Université européenne de Bretagne (France); Guihéneuf, Solène, E-mail: solene.guiheneuf@wanadoo.fr [Université européenne de Bretagne, Université de Rennes 1, Sciences Chimiques de Rennes, UMR, CNRS 6226, Groupe Ingénierie Chimique & Molécules Pour le Vivant (ICMV), Bât. 10A, Campus de Beaulieu, Avenue du Général Leclerc, CS 74205, 35042 Rennes cedex (France); Le Guével, Rémy [Plate-forme ImPACcell Structure Fédérative de Recherche BIOSIT Université de Rennes 1, Bat. 8, Campus de Villejean, 2 Avenue du Pr. Leon Bernard, CS 34317, 35043 Rennes Cedex (France); Biard, Pierre-François [Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7 (France); Université européenne de Bretagne (France); and others

    2016-04-15

    Highlights: • Description of a VOC depollution system suitable with industrial processes, TPPB. • Novel association of TPPB and hydrophobic ionic liquids. • Synthesis of several hydrophobic ionic liquids designed to fit desired properties. • Toxicity evaluation of these ILs towards cells, animals and bacteria. - Abstract: Synthesis of several hydrophobic ionic liquids (ILs), which might be selected as good candidates for degradation of hydrophobic volatile organic compounds in a two-phase partitioning bioreactor (TPPB), were carried out. Several bioassays were also realized, such as toxicity evaluation on activated sludge and zebrafish, cytotoxicity, fluoride release in aqueous phase and biodegradability in order to verify their possible effects in case of discharge in the aquatic environment and/or human contact during industrial manipulation. The synthesized compounds consist of alkylimidazoliums, functionalized imidazoliums, isoqinoliniums, triazoliums, sulfoniums, pyrrolidiniums and morpholiniums and various counter-ions such as: PF{sub 6}{sup −}, NTf{sub 2}{sup −} and NfO{sup −}. Toxicity evaluation on activated sludge of each compound (5% v/v of IL) was assessed by using a glucose uptake inhibition test. Toxicity against zebrafish and cytotoxicity were evaluated by the ImPACCell platform of Rennes (France). Fluoride release in water was estimated by regular measurements using ion chromatography equipment. IL biodegradability was determined by measuring BOD{sub 28} of aqueous samples (compound concentration,1 mM). All ILs tested were not biodegradable; while some of them were toxic toward activated sludge. Isoquinolinium ILs were toxic to human cancerous cell lines. Nevertheless no toxicity was found against zebrafish Danio rerio. Only one IL released fluoride after long-time agitation.

  19. Synthesis and toxicity evaluation of hydrophobic ionic liquids for volatile organic compounds biodegradation in a two-phase partitioning bioreactor

    International Nuclear Information System (INIS)

    Rodriguez Castillo, Alfredo Santiago; Guihéneuf, Solène; Le Guével, Rémy; Biard, Pierre-François

    2016-01-01

    Highlights: • Description of a VOC depollution system suitable with industrial processes, TPPB. • Novel association of TPPB and hydrophobic ionic liquids. • Synthesis of several hydrophobic ionic liquids designed to fit desired properties. • Toxicity evaluation of these ILs towards cells, animals and bacteria. - Abstract: Synthesis of several hydrophobic ionic liquids (ILs), which might be selected as good candidates for degradation of hydrophobic volatile organic compounds in a two-phase partitioning bioreactor (TPPB), were carried out. Several bioassays were also realized, such as toxicity evaluation on activated sludge and zebrafish, cytotoxicity, fluoride release in aqueous phase and biodegradability in order to verify their possible effects in case of discharge in the aquatic environment and/or human contact during industrial manipulation. The synthesized compounds consist of alkylimidazoliums, functionalized imidazoliums, isoqinoliniums, triazoliums, sulfoniums, pyrrolidiniums and morpholiniums and various counter-ions such as: PF_6"−, NTf_2"− and NfO"−. Toxicity evaluation on activated sludge of each compound (5% v/v of IL) was assessed by using a glucose uptake inhibition test. Toxicity against zebrafish and cytotoxicity were evaluated by the ImPACCell platform of Rennes (France). Fluoride release in water was estimated by regular measurements using ion chromatography equipment. IL biodegradability was determined by measuring BOD_2_8 of aqueous samples (compound concentration,1 mM). All ILs tested were not biodegradable; while some of them were toxic toward activated sludge. Isoquinolinium ILs were toxic to human cancerous cell lines. Nevertheless no toxicity was found against zebrafish Danio rerio. Only one IL released fluoride after long-time agitation.

  20. Combining polar organic chemical integrative samplers (POCIS) with toxicity testing to evaluate pesticide mixture effects on natural phototrophic biofilms

    International Nuclear Information System (INIS)

    Pesce, Stephane; Morin, Soizic; Lissalde, Sophie; Montuelle, Bernard; Mazzella, Nicolas

    2011-01-01

    Polar organic chemical integrative samplers (POCIS) are valuable tools in passive sampling methods for monitoring polar organic pesticides in freshwaters. Pesticides extracted from the environment using such methods can be used to toxicity tests. This study evaluated the acute effects of POCIS extracts on natural phototrophic biofilm communities. Our results demonstrate an effect of POCIS pesticide mixtures on chlorophyll a fluorescence, photosynthetic efficiency and community structure. Nevertheless, the range of biofilm responses differs according to origin of the biofilms tested, revealing spatial variations in the sensitivity of natural communities in the studied stream. Combining passive sampler extracts with community-level toxicity tests offers promising perspectives for ecological risk assessment. - Research highlights: → Polar organic chemical integrative samplers (POCIS) were used for monitoring polar organic pesticides in a contaminated river. → The acute effects of POCIS extracts were tested on natural phototrophic biofilm communities. → POCIS pesticide mixtures affected chlorophyll a fluorescence, photosynthetic efficiency and community structure. → Biofilm responses differed according to origin of the biofilms tested, revealing variations in the sensitivity of natural communities. → Combining passive sampler extracts with community-level toxicity tests offers promising perspectives for ecological risk assessment. - Pesticide mixtures extracted from POCIS can affect chl a fluorescence, photosynthetic efficiency and community structure of natural biofilms.

  1. Single- and mixture toxicity of three organic UV-filters, ethylhexyl methoxycinnamate, octocrylene, and avobenzone on Daphnia magna.

    Science.gov (United States)

    Park, Chang-Beom; Jang, Jiyi; Kim, Sanghun; Kim, Young Jun

    2017-03-01

    In freshwater environments, aquatic organisms are generally exposed to mixtures of various chemical substances. In this study, we tested the toxicity of three organic UV-filters (ethylhexyl methoxycinnamate, octocrylene, and avobenzone) to Daphnia magna in order to evaluate the combined toxicity of these substances when in they occur in a mixture. The values of effective concentrations (ECx) for each UV-filter were calculated by concentration-response curves; concentration-combinations of three different UV-filters in a mixture were determined by the fraction of components based on EC 25 values predicted by concentration addition (CA) model. The interaction between the UV-filters were also assessed by model deviation ratio (MDR) using observed and predicted toxicity values obtained from mixture-exposure tests and CA model. The results from this study indicated that observed ECx mix (e.g., EC 10mix , EC 25mix , or EC 50mix ) values obtained from mixture-exposure tests were higher than predicted ECx mix (e.g., EC 10mix , EC 25mix , or EC 50mix ) values calculated by CA model. MDR values were also less than a factor of 1.0 in a mixtures of three different UV-filters. Based on these results, we suggest for the first time a reduction of toxic effects in the mixtures of three UV-filters, caused by antagonistic action of the components. Our findings from this study will provide important information for hazard or risk assessment of organic UV-filters, when they existed together in the aquatic environment. To better understand the mixture toxicity and the interaction of components in a mixture, further studies for various combinations of mixture components are also required. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. From dust to life

    Science.gov (United States)

    Wickramasinghe, Chandra

    After initially challenging the dirty-ice theory of interstellar grains, Fred Hoyle and the present author proposed carbon (graphite) grains, mixtures of refractory grains, organic polymers, biochemicals and finally bacterial grains as models of interstellar dust. The present contribution summarizes this trend and reviews the main arguments supporting a modern version of panspermia.

  3. Migratory birds are the source of highly toxic organic pollutants for indigenous people in the Russian Arctic

    Science.gov (United States)

    Pesiakova, A. A.; Gusakova, E. V.; Trofimova, A. N.; Sorokina, T. Yu

    2018-01-01

    Polychlorinated biphenyls are highly toxic organic contaminants. Due to their chemical properties they had wide application in industry and agriculture in the 20th century. In 2001 the production of PCBs has been prohibited almost worldwide. Environmental contamination has been found in soils, water, and air where there were PCB production sites. They have been detected in fish, birds and animals of migratory species, retaining transboarding transfer. Several migratory species of birds (Taiga bean goose, greater white-fronted goose, lesser white fronted goose and barnacle goose) are a diet for indigenous people. PCBs accumulating in the human body affect all systems and organs. This article reviews the contribution of migratory bird species in transboarding transfer of highly toxic contaminants in the Nenets Autonomous Area, Kolguev island (Russian Arctic).

  4. Gold leaching by organic base polythionates: new non-toxic and secure technology

    OpenAIRE

    Smolyaninov, Vladislav; Shekhvatova, Galina; Vainshtein, Mikhail

    2014-01-01

    The article present a review on own experimental and some published data which are related with the gold leaching. It is well-known that the most common and usual process of the leaching with cyanide can be dangerous, needs a great water consumption, and additional costs for remediation of the poisoned and toxic sites. The experimental data described production of poythionates which are not toxic but perspective for the prosperous gold leaching. The paper dedicated to the safe gold leaching w...

  5. Contribution of transformation products towards the total herbicide toxicity to tropical marine organisms.

    Science.gov (United States)

    Mercurio, Philip; Eaglesham, Geoff; Parks, Stephen; Kenway, Matt; Beltran, Victor; Flores, Florita; Mueller, Jochen F; Negri, Andrew P

    2018-03-19

    The toxicity of herbicide degradation (transformation) products is rarely taken into account, even though these are commonly detected in the marine environment, sometimes at concentrations higher than the parent compounds. Here we assessed the potential contribution of toxicity by transformation products of five photosystem II herbicides to coral symbionts (Symbiodinium sp.), the green algae Dunaliella sp., and prawn (Penaeus monodon) larvae. Concentration-dependent inhibition of photosynthetic efficiency (∆F/F m ') was observed for all herbicides in both microalgal species. The toxicity of solutions of aged diuron solutions containing transformation products to Symbiodinium sp. and Dunaliella sp. was greater than could be explained by the concentrations of diuron measured, indicating transformation products contributed to the inhibition of ∆F/F m '. However, the toxicity of aged atrazine, simazine, hexazinone, and ametryn solutions could be explained by the concentration of parent herbicide, indicating no contribution by transformation products. Prawn larval metamorphosis was not sensitive to the herbicides, but preliminary results indicated some toxicity of the transformation products of atrazine and diuron. Risk assessments should take into account the contribution of herbicide transformation products; however, further studies are clearly needed to test the toxicity of a far wider range of transformation products to a representative diversity of relevant taxa.

  6. A survey of the ambient concentrations and deposition rates of toxic organic micropollutants at urban sites in the United Kingdom

    International Nuclear Information System (INIS)

    Coleman, P.; Clayton, P.; Davis, B.; Donovan, B.; Duff, M.

    1994-01-01

    Warren Spring Laboratory (WSL) coordinates a programme funded by the UK Department of Environment, Air Quality Division, Science Unit. The aim of the programme is to investigate the behaviour of toxic organic micropollutants (TOMP) in the UK environment. Part of this programme involves the measurement of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (dioxins) polychlorinated biphenyls (PCB) and polyaromatic hydrocarbons (PAH) in urban air in the UK. (orig.)

  7. [The toxic and hygienic characteristics of the new synthetic organic flocculants AES-5, AES-7 and AES-10].

    Science.gov (United States)

    Prokopov, V A; Nekrasova, L S; Mudryĭ, I V

    2000-03-01

    A toxicological and hygienic characterization is submitted of novel synthetic organic flocculant AEC-5, AEC-7, AEC-10 which are low-toxicity substances and are classified under the fourth class of hazards. They have no skin-resorptive, locally irritative action and are endowed with a weak cumulative activity of functional character. The AEC-5 flocculant exerts a moderately manifest sensitizing effect in the dermal route of entry.

  8. Linear solvation energy relationships for toxicity of selected organic chemicals to Daphnia pulex and Daphnia magna

    Science.gov (United States)

    Passino, Dora R.M.; Hickey, James P.; Frank, Anthony M.

    1988-01-01

    In the Laurentian Great Lakes, more than 300 contaminants have been identified in fish, other biota, water, and sediment. Current hazard assessment of these chemicals by the National Fisheries Research Center-Great Lakes is based on their toxicity, occurrence in the environment, and source. Although scientists at the Center have tested over 70 chemicals with the crustacean Daphnia pulex, the number of experimental data needed to screen the huge array of chemicals in the Great Lakes exceeds the practical capabilities of conducting bioassays. This limitation can be partly circumvented, however, by using mathematical models based on quantitative structure-activity relationships (QSAR) to provide rapid, inexpensive estimates of toxicity. Many properties of chemicals, including toxicity, bioaccumulation and water solubility are well correlated and can be predicted by equations of the generalized linear solvation energy relationships (LSER). The equation we used to model solute toxicity is Toxicity = constant + mVI/100 + s (π* + dδ) + bβm + aαm where VI = intrinsic (Van der Waals) molar volume; π* = molecular dipolarity/polarizability; δ = polarizability 'correction term'; βm = solute hydrogen bond acceptor basicity; and αm = solute hydrogen bond donor acidity. The subscript m designates solute monomer values for α and β. We applied the LSER model to 48-h acute toxicity data (measured as immobilization) for six classes of chemicals detected in Great Lakes fish. The following regression was obtained for Daphnia pulex (concentration = μM): log EC50 = 4.86 - 4.35 VI/100; N = 38, r2 = 0.867, sd = 0.403 We also used the LSER modeling approach to analyze to a large published data set of 24-h acute toxicity for Daphnia magna; the following regression resulted, for eight classes of compounds (concentration = mM): log EC50 = 3.88 - 4.52 VI/100 - 1.62 π* + 1.66 βm - 0.916 αm; N = 62, r2 = 0.859, sd = 0.375 In addition we developed computer software that identifies

  9. Ensemble mean climatology of snow darkening effect due to deposition of dust, black carbon, and organic carbon as simulated with the NASA GEOS-5 Earth System Model

    Science.gov (United States)

    Yasunari, T. J.; Lau, W. K.; Mahanama, S. P.; Colarco, P. R.; Koster, R. D.; Kim, K.; da Silva, A.

    2013-12-01

    The importance of the snow darkening effect (SDE) caused by solar absorbing aerosols such as dust and black carbon (BC) on climate has been discussed in previous studies. We have developed a snow darkening package for the catchment land surface model coupled to the NASA Goddard Earth Observing System, version 5 (GEOS-5), Earth System Model. Our snow darkening package includes the schemes for snow albedo and mass concentration calculations in polluted snow by dust, BC, and organic carbon (OC) depositions. The snow darkening package is currently available for seasonal snowpack over the model-defined land areas, excluding sea ice and inland of the ice sheets. The depositions of the solar absorbing aerosols are obtained from the GOCART aerosol module in the GEOS-5. Here we show the preliminary results of ensemble mean climatology (EMC) of the full SDE (i.e., dust+BC+OC). Ensemble simulations covering 10-year of 2002-2011 were carried out with the GEOS-5 including and excluding the full SDE for which each has 10 ensemble members. Shortwave radiative forcing (RF) at the top of atmosphere under all-sky condition for the 10-member EMC of the full SDE was relatively larger over Europe, Central Asia (CA), the Himalayas, the Tibetan Plateau (TP), East Asia (EA), Eastern Siberia (ES), the US, and Canadian Arctic. The RF was the strongest over the Himalayas and the TP in the northern hemisphere. The increases of surface air temperature also well correspond to the RF pattern. Larger reductions of snow water equivalent in seasonal snowpack were seen over the Himalayas, the TP, Alaska, Western Canada, and Arctic regions. We will discuss more on the day of the presentation.

  10. Sensitivity and toxic mode of action of dietary organic and inorganic selenium in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Berntssen, M H G; Sundal, T K; Olsvik, P A; Amlund, H; Rasinger, J D; Sele, V; Hamre, K; Hillestad, M; Buttle, L; Ørnsrud, R

    2017-11-01

    Depending on its chemical form, selenium (Se) is a trace element with a narrow range between requirement and toxicity for most vertebrates. Traditional endpoints of Se toxicity include reduced growth, feed intake, and oxidative stress, while more recent finding describe disturbance in fatty acid synthesis as underlying toxic mechanism. To investigate overall metabolic mode of toxic action, with emphasis on lipid metabolism, a wide scope metabolomics pathway profiling was performed on Atlantic salmon (Salmo salar) (572±7g) that were fed organic and inorganic Se fortified diets. Atlantic salmon were fed a low natural background organic Se diet (0.35mg Se kg -1 , wet weight (WW)) fortified with inorganic sodium selenite or organic selenomethionine-yeast (SeMet-yeast) at two levels (∼1-2 or 15mgkg -1 , WW), in triplicate for 3 months. Apparent adverse effects were assessed by growth, feed intake, oxidative stress as production of thiobarbituric acid-reactive substances (TBARS) and levels of tocopherols, as well as an overall metabolomic pathway assessment. Fish fed 15mgkg -1 selenite, but not 15mgkg -1 SeMet-yeast, showed reduced feed intake, reduced growth, increased liver TBARS and reduced liver tocopherol. Main metabolic pathways significantly affected by 15mgkg -1 selenite, and to a lesser extent 15mgkg -1 SeMet-yeast, were lipid catabolism, endocannabinoids synthesis, and oxidant/glutathione metabolism. Disturbance in lipid metabolism was reflected by depressed levels of free fatty acids, monoacylglycerols and diacylglycerols as well as endocannabinoids. Specific for selenite was the significant reduction of metabolites in the S-Adenosylmethionine (SAM) pathway, indicating a use of methyl donors that could be allied with excess Se excretion. Dietary Se levels to respectively 1.1 and 2.1mgkg -1 selenite and SeMet-yeast did not affect any of the above mentioned parameters. Apparent toxic mechanisms at higher Se levels (15mgkg -1 ) included oxidative stress and

  11. Ice formation via deposition nucleation on mineral dust and organics: dependence of onset relative humidity on total particulate surface area

    International Nuclear Information System (INIS)

    Kanji, Zamin A; Florea, Octavian; Abbatt, Jonathan P D

    2008-01-01

    We present ice nucleation results for Arizona test dust, kaolinite, montmorillonite, silica, silica coated with a hydrophobic octyl chain, oxalic acid dihydrate, Gascoyne leonardite (a humic material), and Aldrich humic acid (sodium salt). The focus was on deposition mode nucleation below water saturation at 233 K. Particles were deposited onto a hydrophobic cold stage by atomization of a slurry/solution and exposed to a constant partial pressure of water vapor. By lowering the temperature of the stage, the relative humidity with respect to ice (RH i ) was gradually increased until ice nucleation was observed using digital photography. Different numbers of particles were deposited onto the cold stage by varying the atomization solution concentration and deposition time. For the same total particulate surface area, mineral dust particles nucleated ice at lower supersaturations than all other materials. The most hydrophobic materials, i.e. Gascoyne leonardite and octyl silica, were the least active. For our limit of detection of one ice crystal, the ice onset RH i values were dependent on the total surface area of the particulates, indicating that no unique threshold RH i for ice nucleation prevails

  12. Ice formation via deposition nucleation on mineral dust and organics: dependence of onset relative humidity on total particulate surface area

    Energy Technology Data Exchange (ETDEWEB)

    Kanji, Zamin A; Florea, Octavian; Abbatt, Jonathan P D [Department of Chemistry, University of Toronto, 80 St George Street, Toronto, ON, M5S 3H6 (Canada)], E-mail: zkanji@chem.utoronto.ca

    2008-04-15

    We present ice nucleation results for Arizona test dust, kaolinite, montmorillonite, silica, silica coated with a hydrophobic octyl chain, oxalic acid dihydrate, Gascoyne leonardite (a humic material), and Aldrich humic acid (sodium salt). The focus was on deposition mode nucleation below water saturation at 233 K. Particles were deposited onto a hydrophobic cold stage by atomization of a slurry/solution and exposed to a constant partial pressure of water vapor. By lowering the temperature of the stage, the relative humidity with respect to ice (RH{sub i}) was gradually increased until ice nucleation was observed using digital photography. Different numbers of particles were deposited onto the cold stage by varying the atomization solution concentration and deposition time. For the same total particulate surface area, mineral dust particles nucleated ice at lower supersaturations than all other materials. The most hydrophobic materials, i.e. Gascoyne leonardite and octyl silica, were the least active. For our limit of detection of one ice crystal, the ice onset RH{sub i} values were dependent on the total surface area of the particulates, indicating that no unique threshold RH{sub i} for ice nucleation prevails.

  13. Building Blocks of Dust and Large Organic Molecules: a Coordinated Laboratory and Astronomical Study of AGB Stars

    Science.gov (United States)

    McCarthy, Michael C.; Gottlieb, Carl A.; Cernicharo, Jose

    2017-06-01

    The increased sensitivity and angular resolution of high-altitude ground-based interferometers in the sub-millimeter band has enabled the physics and chemistry of carbon- and oxygen-rich evolved stars to be re-examined at an unprecedented level of detail. Observations of rotational lines in the inner envelope - the region within a few stellar radii of the central star where the molecular seeds of dust are formed - allows one to critically assess models of dust growth. Interferometric observations of the outer envelope provide stringent tests of neutral and ionized molecule formation. All of the astronomical studies are crucially dependent on precise laboratory measurements of the rotational spectra of new species and of vibrationally excited levels of known molecules and their rare isotopic species. By means of a closely coordinated laboratory and astronomical program, a number of exotic species including the disilicon carbide SiCSi, titanium oxides TiO and TiO_2, and carbon chain anions ranging from CN^- to C_8H^- have recently been observed in evolved stars. This talk will provide overview of these findings, and how they impact current models of the ``chemical laboratories'' of evolved stars. Ongoing laboratory studies of small silicon-bearing molecules such as H_2SiO_2 and vibrationally excited SiC_2 will be highlighted.

  14. Comparing rankings of selected TRI organic chemicals for two environments using a level III fugacity model and toxicity

    International Nuclear Information System (INIS)

    Edwards, F.G.; Egemen, E.; Nirmalakhandan, N.

    1998-01-01

    The Toxics Release Inventory, TRI (USEPA, 1995) is a comprehensive listing of chemicals, mass released, source of releases, and other related information for chemicals which are released into the environment in the US. These chemicals are then ranked according to the mass released as a indication of their environmental impact. Industries have been encouraged to adopt production methods to decrease the release of chemicals which are ranked highly in the TRI. Clearly, this ranking of the chemicals based upon the mass released fails to take into account very important environmental aspects. The first and most obvious aspect is the wide range of toxicity's of the chemicals released. Numerous researchers have proposed systems to rank chemicals according to their toxicity. The second aspect, which a mass released based ranking does not take into account, is the fate and transport of each chemical within the environment. Cohen and Ryan (1985) and Mackay and Paterson (1991) have proposed models to evaluate the fate and transport of chemicals released into the environment. Some authors have incorporated the mass released and toxicity with some fate and transport aspects to rank the impact of released chemicals. But, due to the complexities of modeling the environment, the lack of published data on properties of chemicals, and the lack of information on the speciation of chemicals in complex systems, modeling the fate and transport of toxic chemicals in the environment remains difficult. To provide an indication of the need to rank chemicals according to their environmental impact instead of the mass released, the authors have utilized a subset of 45 organic chemicals from the TRI, modeled the fate and transport of the chemicals using a Level III fugacity model, and compared those equilibrium concentrations with toxicity data to yield a hazard value for each chemical

  15. Toxic potential of organic constituents of submicron particulate matter (PM1) in an urban road site (Barcelona).

    Science.gov (United States)

    Mesquita, Sofia R; van Drooge, Barend L; Dall'Osto, Manuel; Grimalt, Joan O; Barata, Carlos; Vieira, Natividade; Guimarães, Laura; Piña, Benjamin

    2017-06-01

    Atmospheric particulate matter (PM) is a recognized risk factor contributing to a number of diseases in human populations and wildlife globally. Organic matter is a major component of PM, but its contribution to overall toxicity of PM has not been thoroughly evaluated yet. In the present work, the biological activity of organic extracts from PM1 (particles with less than 1 μm of aerodynamic diameter) collected from an urban road site in the centre of Barcelona (NE Spain) was evaluated using a yeast-based assay (AhR-RYA) and different gene expression markers in zebrafish embryos. Dioxin-like activity of the extracts correlated to primary emissions from local traffic exhausts, reflecting weekday/weekend alternance. Expression levels of cyp1a and of gene markers for key cellular processes and development (ier2, fos) also correlated to vehicle emissions, whereas expression of gene markers related to antioxidant defence and endocrine effects (gstal, hao1, ttr) was strongly reduced in samples with strong contribution from regional air masses with aged secondary organic species or with strong influence of biomass burning emissions. Our data suggest that the toxic potential of PM1 organic chemical constituents strongly depends on the emission sources and on the process of ageing from primary to secondary organic aerosols.

  16. An indicator for effects of organic toxicants on lotic invertebrate communities: Independence of confounding environmental factors over an extensive river continuum

    International Nuclear Information System (INIS)

    Beketov, Mikhail A.; Liess, Matthias

    2008-01-01

    Distinguishing between effects of natural and anthropogenic environmental factors on ecosystems is a fundamental problem in environmental science. In river systems the longitudinal gradient of environmental factors is one of the most relevant sources of dissimilarity between communities that could be confounded with anthropogenic disturbances. To test the hypothesis that in macroinvertebrate communities the distribution of species' sensitivity to organic toxicants is independent of natural longitudinal factors, but depends on contamination with organic toxicants, we analysed the relationship between community sensitivity SPEAR organic (average community sensitivity to organic toxicants) and natural and anthropogenic environmental factors in a large-scale river system, from alpine streams to a lowland river. The results show that SPEAR organic is largely independent of natural longitudinal factors, but strongly dependent on contamination with organic toxicants (petrochemicals and synthetic surfactants). Usage of SPEAR organic as a stressor-specific longitude-independent measure will facilitate detection of community disturbance by organic toxicants. - Indicator for organic toxicants at community level can be independent of natural environmental factors

  17. Toxicity of tetramethylammonium hydroxide to aquatic organisms and its synergistic action with potassium iodide.

    Science.gov (United States)

    Mori, Izumi C; Arias-Barreiro, Carlos R; Koutsaftis, Apostolos; Ogo, Atsushi; Kawano, Tomonori; Yoshizuka, Kazuharu; Inayat-Hussain, Salmaan H; Aoyama, Isao

    2015-02-01

    The aquatic ecotoxicity of chemicals involved in the manufacturing process of thin film transistor liquid crystal displays was assessed with a battery of four selected acute toxicity bioassays. We focused on tetramethylammonium hydroxide (TMAH, CAS No. 75-59-2), a widely utilized etchant. The toxicity of TMAH was low when tested in the 72 h-algal growth inhibition test (Pseudokirchneriellia subcapitata, EC50=360 mg L(-1)) and the Microtox® test (Vibrio fischeri, IC50=6.4 g L(-1)). In contrast, the 24h-microcrustacean immobilization and the 96 h-fish mortality tests showed relatively higher toxicity (Daphnia magna, EC50=32 mg L(-1) and Oryzias latipes, LC50=154 mg L(-1)). Isobologram and mixture toxicity index analyses revealed apparent synergism of the mixture of TMAH and potassium iodide when examined with the D. magna immobilization test. The synergistic action was unique to iodide over other halide salts i.e. fluoride, chloride and bromide. Quaternary ammonium ions with longer alkyl chains such as tetraethylammonium and tetrabutylammonium were more toxic than TMAH in the D. magna immobilization test. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Waste Load Allocation for Whole Effluent Toxicity to Protect Aquatic Organisms

    Science.gov (United States)

    Hutcheson, M. R.

    1992-11-01

    A process is developed to determine a waste load allocation that will implement the narrative criteria for fish and wildlife propagation found in states' water quality standards. The waste load allocation to implement the narrative chronic criterion is determined to be percent effluent at a location in the receiving stream, as opposed to an effluent concentration derived from the numerical waste load allocation process. A typical narrative chronic criterion is "receiving streams shall not exhibit chronic toxicity outside the mixing zone," while a typical numerical chronic criterion is "receiving stream concentration shall not exceed 0.005 μg/L of chlordane outside the mixing zone." Toxicity tests are used to implement narrative criteria, while compliance with numerical criteria involves concentration measurements. It is shown that the appropriate percent effluent is inversely proportional to the dilution factor for chronic toxicity. An appropriate waste load allocation to implement the narrative acute criterion is 100% effluent. Waste load allocation for whole effluent toxicity is feasible. The required independent variables are available to regulatory agencies, and toxicity testing has become routine.

  19. Vermicomposting eliminates the toxicity of Lantana (Lantana camara) and turns it into a plant friendly organic fertilizer

    Energy Technology Data Exchange (ETDEWEB)

    Hussain, N.; Abbasi, Tasneem; Abbasi, S.A., E-mail: prof.s.a.abbasi@gmail.com

    2015-11-15

    Highlights: • It is shown for the first time that Lantana can lose its toxicity when vermicomposted. • The Lantana vermicompost is shown to be a good organic fertilizer. • FTIR studies identified Lantana’s toxic constituents destroyed by vermicomposting. • The findings have far-reaching implications in the gainful use of harmful weeds. - Abstract: In evidently the first study of its kind, vermicompost derived solely from a weed known to possess plant and animal toxicity was used to assess its impact on the germination and early growth of several plant species. No pre-composting or supplementation of animal manure was done to generate the vermicompost in order to ensure that the impact is clearly attributable to the weed. Whereas the weed used in this study, Lantana (Lantana camara), is known to possess strong negative allelopathy, besides plant/animal toxicity in other forms, its vermicompost was seen to be a good organic fertilizer as it increased germination success and encouraged growth of all the three botanical species explored by the authors – green gram (Vigna radiata), ladies finger (Abelmoschus esculentus) and cucumber (Cucumis sativus). In terms of several physical, chemical and biochemical attributes that were studied, the vermicompost appeared plant-friendly, giving best results in general when employed at concentrations of 1.5% in soil (w/w). Fourier transform infrared spectrometry revealed that the phenols and the sesquiterpene lactones that are responsible for the allelopathic impact of Lantana were largely destroyed in the course of vermicomposting. There is also an indication that lignin content of Lantana was reduced during its vermicomposting. The findings open up the possibility that the billions of tons of phytomass that is generated annually by Lantana and other invasives can be gainfully utilized in generating organic fertilizer via vermicomposting.

  20. Vermicomposting eliminates the toxicity of Lantana (Lantana camara) and turns it into a plant friendly organic fertilizer

    International Nuclear Information System (INIS)

    Hussain, N.; Abbasi, Tasneem; Abbasi, S.A.

    2015-01-01

    Highlights: • It is shown for the first time that Lantana can lose its toxicity when vermicomposted. • The Lantana vermicompost is shown to be a good organic fertilizer. • FTIR studies identified Lantana’s toxic constituents destroyed by vermicomposting. • The findings have far-reaching implications in the gainful use of harmful weeds. - Abstract: In evidently the first study of its kind, vermicompost derived solely from a weed known to possess plant and animal toxicity was used to assess its impact on the germination and early growth of several plant species. No pre-composting or supplementation of animal manure was done to generate the vermicompost in order to ensure that the impact is clearly attributable to the weed. Whereas the weed used in this study, Lantana (Lantana camara), is known to possess strong negative allelopathy, besides plant/animal toxicity in other forms, its vermicompost was seen to be a good organic fertilizer as it increased germination success and encouraged growth of all the three botanical species explored by the authors – green gram (Vigna radiata), ladies finger (Abelmoschus esculentus) and cucumber (Cucumis sativus). In terms of several physical, chemical and biochemical attributes that were studied, the vermicompost appeared plant-friendly, giving best results in general when employed at concentrations of 1.5% in soil (w/w). Fourier transform infrared spectrometry revealed that the phenols and the sesquiterpene lactones that are responsible for the allelopathic impact of Lantana were largely destroyed in the course of vermicomposting. There is also an indication that lignin content of Lantana was reduced during its vermicomposting. The findings open up the possibility that the billions of tons of phytomass that is generated annually by Lantana and other invasives can be gainfully utilized in generating organic fertilizer via vermicomposting

  1. Comparison of toxicity of class-based organic chemicals to algae and fish based on discrimination of excess toxicity from baseline level.

    Science.gov (United States)

    Li, Jin J; Tai, Hong W; Yu, Yang; Wen, Yang; Wang, Xiao H; Zhao, Yuan H

    2015-07-01

    Toxicity data to fish and algae were used to investigate excess toxicity between species. Results show that chemicals exhibiting excess toxicity to fish also show excess toxicity to algae for most of the compounds. This indicates that they share the same mode of action between species. Similar relationships between logKOW and toxicities to fish and algae for baseline and less inert compounds suggest that they have similar critical body residues in the two species. Differences in excess toxicity for some compounds suggest that there is a difference of physiological structure and metabolism between fish and algae. Some reactive compounds (e.g. polyamines) exhibit greater toxic effects for algae than those for fish because of relatively low bio-uptake potential of these hydrophilic compounds in fish as compared with that in algae. Esters exhibiting greater toxicity in fish than that in algae indicate that metabolism can affect the discrimination of excess toxicity from baseline level. Algae growth inhibition is a very good surrogate for fish lethality. This is not only because overall toxicity sensitivity to algae is greater than that to fish, but also the excess toxicity calculated from algal toxicity can better reflect reactivity of compounds with target molecules than fish toxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Toxic Volatile Organic Compounds (VOCs in the Atmospheric Environment: Regulatory Aspects and Monitoring in Japan and Korea

    Directory of Open Access Journals (Sweden)

    Wen-Tien Tsai

    2016-09-01

    Full Text Available In the past decades, hazardous air pollutants (HAPs, so-called air toxics or toxic air pollutants, have been detected in the atmospheric air at low concentration levels, causing public concern about the adverse effect of long-term exposure to HAPs on human health. Most HAPs belong to volatile organic compounds (VOCs. More seriously, most of them are known carcinogens or probably carcinogenic to humans. The objectives of this paper were to report the regulatory aspects and environmental monitoring management of toxic VOCs designated by Japan and Korea under the Air Pollution Control Act, and the Clean Air Conservation Act, respectively. It can be found that the environmental quality standards and environmental monitoring of priority VOCs (i.e., benzene, trichloroethylene, tetrachloroethylene, and dichloromethane have been set and taken by the state and local governments of Japan since the early 2000, but not completely established in Korea. On the other hand, the significant progress in reducing the emissions of some toxic VOCs, including acrylonitrile, benzene, 1,3-butadiene, 1,2-dichloroethane, dichloromethane, chloroform, tetrachloroethylene, and trichloroethylene in Japan was also described as a case study in the brief report paper.

  3. Granular activated carbon for simultaneous adsorption and biodegradation of toxic oil sands process-affected water organic compounds.

    Science.gov (United States)

    Islam, Md Shahinoor; Zhang, Yanyan; McPhedran, Kerry N; Liu, Yang; Gamal El-Din, Mohamed

    2015-04-01

    Naphthenic acids (NAs) released into oil sands process-affected water (OSPW) during bitumen processing in Northern Alberta are problematic for oil sands industries due to their toxicity in the environment and resistance to degradation during conventional wastewater treatment processes. Granular activated carbon (GAC) has shown to be an effective media in removing biopersistent organics from wastewater using a combination of adsorption and biodegradation removal mechanisms. A simultaneous GAC (0.4 g GAC/L) adsorption and biodegradation (combined treatment) study was used for the treatment of raw and ozonated OSPW. After 28 days of batch treatment, classical and oxidized NAs removals for raw OSPW were 93.3% and 73.7%, and for ozonated OSPW were 96.2% and 77.1%, respectively. Synergetic effects of the combined treatment process were observed in removals of COD, the acid extractable fraction, and oxidized NAs, which indicated enhanced biodegradation and bioregeneration in GAC biofilms. A bacteria copy number >10(8) copies/g GAC on GAC surfaces was found using quantitative real time polymerase chain reaction after treatment for both raw and ozonated OSPW. A Microtox(®) acute toxicity test (Vibrio fischeri) showed effective toxicity removal (>95.3%) for the combined treatments. Therefore, the simultaneous GAC adsorption and biodegradation treatment process is a promising technology for the elimination of toxic OSPW NAs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Effect of long-term equilibration on the toxicity of molybdenum to soil organisms

    International Nuclear Information System (INIS)

    Gestel, Cornelis A.M. van; McGrath, Steve P.; Smolders, Erik; Diez Ortiz, Maria; Borgman, Eef; Verweij, Rudo A.; Buekers, Jurgen; Oorts, Koen

    2012-01-01

    To determine if long-term equilibration may alleviate molybdenum toxicity, earthworms, enchytraeids, collembolans and four plant species were exposed to three soils freshly spiked with Na 2 MoO 4 .2H 2 O and equilibrated for 6 or 11 months in the field with free drainage. Total Mo concentrations in soil decreased by leaching, most (up to 98%) in sandy soil and less (54–62%) in silty and clayey soils. Changes in residual Mo toxicity with time were inconclusive in sandy soil. In the other two soils, toxicity of residual total Mo was significantly reduced after 11 months equilibration with a median 5.5-fold increase in ED50s. Mo fixation in soil, i.e. the decrease of soil solution Mo concentrations at equivalent residual total soil Mo, was maximally a factor of 2.1 only. This experiment shows natural attenuation of molybdate ecotoxicity under field conditions is related to leaching of excess Mo and other ions as well as to slow ageing reactions. - Highlights: ► Three molybdate-spiked soils were equilibrated for 6 and 11 months outdoors. ► Mo chronic toxicity to earthworms, enchytraeids, Collembola and four plant species was assessed. ► Mo concentrations in all soils decreased due to leaching. ► Based on actual total Mo remaining in the soil, Mo toxicity decreased by a median factor of 5.5. ► Decreased Mo toxicity was due to leaching as well as slow ageing reactions. - Natural attenuation under field conditions is more related to leaching of excess molybdate than to slow ageing reactions

  5. Toxicity on aquatic organisms exposed to secondary effluent disinfected with chlorine, peracetic acid, ozone and UV radiation.

    Science.gov (United States)

    da Costa, Juliana Berninger; Rodgher, Suzelei; Daniel, Luiz Antonio; Espíndola, Evaldo Luiz Gaeta

    2014-11-01

    The toxic potential of four disinfectant agents (chlorine, ozone, peracetic acid and UV radiation), used in the disinfection of urban wastewater, was evaluated with respect to four aquatic organisms. Disinfection assays were carried out with wastewater from the city of Araraquara (São Paulo State, Brazil), and subsequently, toxicity bioassays were applied in order to verify possible adverse effects to the cladocerans (Ceriodaphnia silvestrii and Daphnia similis), midge larvae Chironomus xanthus and fish (Danio rerio). Under the experimental conditions tested, all the disinfectants were capable of producing harmful effects on the test organisms, except for C. xanthus. The toxicity of the effluent to C. silvestrii was observed to increase significantly as a result of disinfection using 2.5 mg L(-1) chlorine and 29.9 mg L(-1) ozone. Ozonation and chlorination significantly affected the survival of D. similis and D. rerio, causing mortality of 60 to 100 % in comparison to the non-disinfected effluent. In experiments with effluent treated with peracetic acid (PAA) and UV radiation, a statistically significant decrease in survival was only detected for D. rerio. This investigation suggested that the study of the ideal concentrations of disinfectants is a research need for ecologically safe options for the treatment of wastewater.

  6. The Toxicity of Nitroguanidine and Photolyzed Nitroguandine to Freshwater Aquatic Organisms

    Science.gov (United States)

    1985-03-01

    presently stored in lagoons and holding ponds; release of Wu could result from leakage, overflows, or leaching from the storage facilities. 2...111-112. *16. American Society for Testing and Materials. 1980. Standard practice for conducting acute toxicity tests with fishes, macroinvertebrates

  7. Organ specific acute toxicity of the carcinogen trans-4-acetylaminostilbene is not correlated with macromolecular binding.

    Science.gov (United States)

    Pfeifer, A; Neumann, H G

    1986-09-01

    trans-4-Acetylaminostilbene (trans-AAS) is acutely toxic in rats and lesions are produced specifically in the glandular stomach. Toxicity is slightly increased by pretreating the animals with phenobarbital (PB) and is completely prevented by pretreatment with methylcholanthrene (MC). The prostaglandin inhibitors, indomethacin and acetyl salicylic acid, do not reduce toxicity. The high efficiency of MC suggested that toxicity is caused by reactive metabolites. trans-[3H]-AAS was administered orally to untreated and to PB- or MC-pretreated female Wistar rats and target doses in different tissues were measured by means of covalent binding to proteins, RNA and DNA. Macromolecular binding in the target tissue of poisoned animals was significantly lower than in liver and kidney and comparable to other non-target tissues. Pretreatment with MC lowered macromolecular binding in all extrahepatic tissues but not in liver. These findings are not in line with tissue specific metabolic activation. The only unique property of the target tissue, glandular stomach, that we observed was a particular affinity for the systemically available parent compound. In the early phase of poisoning, tissue concentrations were exceedingly high and the stomach function was impaired.

  8. Innovative reactor technology for selective oxidation of toxic organic pollutants in wastewater by ozone

    NARCIS (Netherlands)

    Boncz, M.A.; Bruning, H.; Rulkens, W.H.

    2003-01-01

    Ozonation can be a suitable technique for the pre-treatment of wastewater containing low concentrations of toxic or non-biodegradable compounds that cannot be treated with satisfactory results when only the traditional, less expensive biological techniques are applied. In this case, the oxidation

  9. Bioaccumulation of potentially toxic trace elements in benthic organisms of Admiralty Bay (King George Island, Antarctica)

    International Nuclear Information System (INIS)

    Majer, Alessandra Pereira; Petti, Mônica Angélica Varella; Corbisier, Thais Navajas; Ribeiro, Andreza Portella; Theophilo, Carolina Yume Sawamura; Ferreira, Paulo Alves de Lima; Figueira, Rubens Cesar Lopes

    2014-01-01

    Highlights: • Toxic metals were released in the 2012 fire in the Brazilian base at Admiralty Bay. • Potentially toxic metals were measured in eight Antarctic benthos species. • The bioaccumulation of As, Cd and Pb was verified in the studied species. • The biomagnification of Cd is suggested for the studied Antarctic food web. - Abstract: Data about the concentration, accumulation and transfer of potentially toxic elements in Antarctic marine food webs are essential for understanding the impacts of these elements, and for monitoring the pollution contribution of scientific stations, mainly in Admiralty Bay due to the 2012 fire in the Brazilian scientific station. Accordingly, the concentration of As, Cd, Cu, Ni, Pb and Zn was measured in eight benthic species collected in the 2005/2006 austral summer and the relationship between concentration and trophic position (indicated by δ 15 N values) was tested. A wide variation in metal content was observed depending on the species and the element. In the studied trophic positions, it was observed bioaccumulation for As, Cd and Pb, which are toxic elements with no biological function. In addition, Cd showed a positive relationship between concentration and trophic level suggesting the possible biomagnification of this element

  10. Toxicity of the fluoroquinolone antibiotics enrofloxacin and ciprofloxacin to photoautotrophic aquatic organisms.

    Science.gov (United States)

    Ebert, Ina; Bachmann, Jean; Kühnen, Ute; Küster, Anette; Kussatz, Carola; Maletzki, Dirk; Schlüter, Christoph

    2011-12-01

    The present study investigated the growth inhibition effect of the fluoroquinolone antibiotics enrofloxacin and ciprofloxacin on four photoautotrophic aquatic species: the freshwater microalga Desmodesmus subspicatus, the cyanobacterium Anabaena flos-aquae, the monocotyledonous macrophyte Lemna minor, and the dicotyledonous macrophyte Myriophyllum spicatum. Both antibiotics, which act by inhibiting the bacterial DNA gyrase, demonstrated high toxicity to A. flos-aquae and L. minor and moderate to slight toxicity to D. subspicatus and M. spicatum. The cyanobacterium was the most sensitive species with median effective concentration (EC50) values of 173 and 10.2 µg/L for enrofloxacin and ciprofloxacin, respectively. Lemna minor proved to be similarly sensitive, with EC50 values of 107 and 62.5 µg/L for enrofloxacin and ciprofloxacin, respectively. While enrofloxacin was more toxic to green algae, ciprofloxacin was more toxic to cyanobacteria. Calculated EC50s for D. subspicatus were 5,568 µg/L and >8,042 µg/L for enrofloxacin and ciprofloxacin, respectively. These data, as well as effect data from the literature, were compared with predicted and reported environmental concentrations. For two of the four species, a risk was identified at ciprofloxacin concentrations found in surface waters, sewage treatment plant influents and effluents, as well as in hospital effluents. For ciprofloxacin the results of the present study indicate a risk even at the predicted environmental concentration. In contrast, for enrofloxacin no risk was identified at predicted and measured concentrations. Copyright © 2011 SETAC.

  11. Effect of keratin on heavy metal chelation and toxicity to aquatic organisms

    Energy Technology Data Exchange (ETDEWEB)

    Coello, W.F.; Khan, M.A.Q. [Univ. of Illinois, Chicago, IL (United States). Dept. of Biological Sciences

    1998-12-31

    The presence of fresh scales and human hair in water can reduce the toxicity of lead nitrate at and above 6 ppb to fish. This ability is lost on drying and storage, but can be restored if dried hair or scales are treated with a solution of amino acids. The chelation ability of keratin in amino acid-treated scales or hair is retained for months on dry storage. Addition of these hair and/or scales to solutions of lead nitrate, mercuric chloride and a mixture of both, and cupric sulfate reduced the toxicity of these solutions to Daphnia magna and Dreissena polymorpha (zebra mussels). Toxicity of 10 ppm solutions of salts of 27 different metals to daphnids was similarly reduced after filtration through scales or hair. A mixture of a 2 ppb concentration of each of these 27 metals also became nonlethal to daphnids in the presence of, or filtration through, treated scales or hair. 0.25 g of treated hair or scale can be used indefinitely, again and again, to remove the mixture of these 27 metals from their fresh solution in 1 L water if the keratin is frequently rinsed with 0.1% nitric acid to remove the bound metals. The keratin in scales, this, may be the most important ectodermal secretion in absorbing metals from polluted environments and in providing protection against their toxic levels.

  12. [The toxicity variation of organic extracts in drinking water treatment processes].

    Science.gov (United States)

    Mei, M; Wei, S; Zijian, W; Wenhua, W; Baohua, Z; Suxia, Z

    2001-01-01

    Source water samples and outlet water samples from different treatment processes of the Beijing Ninth Water Works were concentrated in situ with XAD-2 filled columns. GC-MS analysis and toxic assessment including acute toxicity evaluation by luminescent bacterium bioassay(Q67 strains) and mutagenicity assessment by Ames test(TA98 and TA100 strains with and without S9 addition) were conducted on these samples. The results showed that prechlorination caused the direct and indirect frame shift mutagenicity as well as indirect base pair substitute mutagenicity. Addition of coagulant may increase the base pair substitute mutagenic effects greatly. Sand and coal filtration and granular activated carbon filtration could effectively remove most of the formed mutagens. The rechlorination do not obviously increase the mutagenic effects. No mutagenic effect was observed in tap water. Acute toxicity showed the same variation with that of mutagenicity during the treatment processes. Sample from flocculation treatment process was found to be the most toxic sample. Results of GC-MS analysis showed that water in this plant was not contaminated by PCB. Concentrations of toluene, naphthalene and phenol increased in flocculation treatment process and in tap water. However, the concentrations of these substances were at the level of microgram/L, therefore, were not high enough to cause mutagenicity.

  13. Acute toxicity of double-walled carbon nanotubes to three aquatic organisms

    CSIR Research Space (South Africa)

    Lukhele, LP

    2015-01-01

    Full Text Available , respectively. In the presence of humic acid high DWCNTs acute toxicity towards D. pulex and P. reticulata was observed but ionic strength led to opposite effect irrespective of DWCNTs form. Both humic acid and ionic strength shielded the P. subcapitata from...

  14. Toxicity evaluation of chlorinated organic compounds using immortalized rat hepatocytes; Fushika rat kansaibo wo mochiita yuki enso kagobutsu no dokusei hyoka no kokoromi

    Energy Technology Data Exchange (ETDEWEB)

    Sone, H; Nakajima, M; Yonemoto, J [National Institute for Environmental Studies, Tsukuba (Japan)

    1997-11-10

    Chlorinated organic compounds has high priority for toxicity screening among environmental hazardous chemicals. In the present study, we used immortalized rat hepatocytes as a liver model in vitro to evaluate the toxicity of nine chlorinated organic compounds. Toxicity of nine chlorinated organic compounds were evaluated to cellular viability of immortalized rat hapatocytes. The potency of the toxicity based on 50% inhibitory concentration (IC50) value was in the following order: triclocalban>triclosan>3,4-dichloroaniline>2,5-diclorophenol> 2,5-dichloroanisole>p-dichlorobenzene> p-chloroaniline>o-dichlorobenzene=tris (2-chloroethyl) phosphate. The rank order of cytotoxic potency of nine chemicals was compared with toxicity information using animals. The rank order of cytotoxic potency did not relative to the order referenced mean lethal dose (LD50) as an index of acute toxicity of rats or mice. However, the rank order of cytotoxic potency relatively correlated non-observed adverse effect level (NOAEL) under the exposure duration adjusted for chronic toxicity in vivo. These data suggests that the origin of testing cell had better to make match target organ of toxic chemicals for extrapolation from data of bioassay in vitro to in vivo. 16 refs., 2 figs., 3 tabs.

  15. Urgent need to reevaluate the latest World Health Organization guidelines for toxic inorganic substances in drinking water.

    Science.gov (United States)

    Frisbie, Seth H; Mitchell, Erika J; Sarkar, Bibudhendra

    2015-08-13

    The World Health Organization (WHO) has established guidelines for drinking-water quality that cover biological and chemical hazards from both natural and anthropogenic sources. In the most recent edition of Guidelines for Drinking-water Quality (2011), the WHO withdrew, suspended, did not establish, or raised guidelines for the inorganic toxic substances manganese, molybdenum, nitrite, aluminum, boron, nickel, uranium, mercury, and selenium. In this paper, we review these changes to the WHO drinking-water guidelines, examining in detail the material presented in the WHO background documents for each of these toxic substances. In some cases, these WHO background documents use literature reviews that do not take into account scientific research published within the last 10 or more years. In addition, there are instances in which standard WHO practices for deriving guidelines are not used; for example, rounding and other mathematical errors are made. According to published meeting reports from the WHO Chemical Aspects Working Group, the WHO has a timetable for revising some of its guidelines for drinking-water quality, but for many of these toxic substances the planned changes are minimal or will be delayed for as long as 5 years. Given the limited nature of the planned WHO revisions to the inorganic toxic substances and the extended timetable for these revisions, we suggest that governments, researchers, and other stakeholders might establish independent recommendations for inorganic toxic substances and possibly other chemicals to proactively protect public health, or at the very least, revert to previous editions of the Guidelines for Drinking-water Quality, which were more protective of public health.

  16. The Presence of Algae Mitigates the Toxicity of Copper-Based Algaecides to a Non-Target Organism.

    Science.gov (United States)

    Bishop, West M; Willis, Ben E; Richardson, Robert J; Cope, W Gregory

    2018-05-07

    Copper-based algaecides are routinely applied to target noxious algal blooms in freshwaters. Standard toxicity testing data with copper suggest typical concentrations used to control algae can cause deleterious acute impacts to non-target organisms. These "clean" water experiments lack algae, which are specifically targeted in field applications of algaecides and contain competing ligands. This research measured the influence of algae on algaecide exposure and subsequent response of the non-target species Daphnia magna to copper sulfate and an ethanolamine-chelated copper algaecide (Captain®). Significant shifts (Palgae were present in exposures along with a copper salt or chelated copper formulation. Copper sulfate 48-h LC50 values shifted from 75.3 to 317.8 and 517.8 µg Cu/L whereas Captain increased from 353.8 to 414.2 and 588.5 µg Cu/L in no algae, 5 × 10 5 and 5 × 10 6 cells/mL algae treatments, respectively. Larger shifts were measured with copper sulfate exposures, although Captain was less toxic to Daphnia magna in all corresponding treatments. Captain was more effective at controlling Scenedesmus dimorphus at most concentrations, and control was inversely proportional to toxicity to D. magna. Overall, incorporating target competing ligands (i.e., algae) into standard toxicity testing is important for accurate risk assessment, and copper formulation can significantly alter algaecidal efficacy and risks to non-target organisms. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. Assessing the fate and toxicity of Thallium I and Thallium III to three aquatic organisms.

    Science.gov (United States)

    Rickwood, C J; King, M; Huntsman-Mapila, P

    2015-05-01

    Thallium has been shown to significantly increase in both water and aquatic biota after exposure to metal mine effluent, however, there is a lack of knowledge as to its fate and effect in the aquatic environment. The objectives of this project were to assess (1) fate of thallium by conducting speciation analysis and determining the influence of water quality on toxicity and (2) effects of thallium (I) and (III) on three aquatic species; the algae, Pseudokirchneriella subcapitata, the invertebrate Ceriodaphnia dubia and the vertebrate Pimephales promelas. Speciation analysis proved challenging with poor recovery of thallium (I), however analysis with solutions >125μg/L revealed that over a 7-d period, recovery of thallium (III) was less than 15%, suggesting that the majority of thallium (III) was converted to Thallium (I). It was only in fresh solutions where recovery of Thallium (III) was greater than 80%. The lowest IC25s generated during our effects assessment for both Thallium (I) and (III) were more than 10-fold greater than the highest concentration recorded in receiving environments (8μg/L) and more than 100-fold greater than the current guideline (0.8μg/L). To assess the influence of water quality on thallium toxicity, the concentrations of both potassium and calcium were reduced in dilution water. When potassium was reduced for both C. dubia and P. subcapitata tests, the lowest IC25 generated was 5-fold higher than the current guideline, but within the range of concentrations reported in receiving environments for both Thallium (I) and (III). When calcium was reduced in dilution water, toxicity only increased in the Tl (III) tests with C. dubia; the IC25 for Tl(III), similar to the exposures conducted with reduced potassium, was within the range of total thallium concentrations reported in the receiving environment. Without an accurate, repeatable method to assess thallium speciation at low concentrations it is not possible to draw any firm conclusions

  18. Interaction of silver nanoparticles with biological objects: antimicrobial properties and toxicity for the other living organisms

    Energy Technology Data Exchange (ETDEWEB)

    Egorova, E M, E-mail: emenano@mail.ru [Laboratory of Nanopathology, Institute of General Pathology and Patophysiology of RAMS, Baltijskaya st., 8, 125315 Moscow (Russian Federation); Science-technology Company ' Nanomet' , Moscow (Russian Federation)

    2011-04-01

    This paper presents several examples of the biological effects of small-sized silver nanoparticles (10.5{+-}3.5nm) observed in experiments on bacteria, slim mold, unicellular alga and plant seeds. The nanoparticles were prepared by the biochemical synthesis, based on the reduction of metal ions in reverse vicelles by biological reductants - natural plant pigments (flavonoids). It is found that, except for the plant seeds, silver nanoparticles (SNP) act as a strong toxic agent, both in water solution and as part of liquid-phase material. It is shown also that the biological action of silver nanoparticles can not be reduced to the toxic action of silver ions in equivalent concentrations or to that of the surfactant (the SNP stabilizer) present in the SNP water solution. Possible SNP applications are suggested.

  19. Interaction of silver nanoparticles with biological objects: antimicrobial properties and toxicity for the other living organisms

    International Nuclear Information System (INIS)

    Egorova, E M

    2011-01-01

    This paper presents several examples of the biological effects of small-sized silver nanoparticles (10.5±3.5nm) observed in experiments on bacteria, slim mold, unicellular alga and plant seeds. The nanoparticles were prepared by the biochemical synthesis, based on the reduction of metal ions in reverse vicelles by biological reductants - natural plant pigments (flavonoids). It is found that, except for the plant seeds, silver nanoparticles (SNP) act as a strong toxic agent, both in water solution and as part of liquid-phase material. It is shown also that the biological action of silver nanoparticles can not be reduced to the toxic action of silver ions in equivalent concentrations or to that of the surfactant (the SNP stabilizer) present in the SNP water solution. Possible SNP applications are suggested.

  20. Bioconcentration and acute toxicity of polycyclic musks in two benthic organisms (Chironomus riparius and Lumbriculus variegatus)

    NARCIS (Netherlands)

    Artola-Garicano, E.; Sinnige, T.L.; Holsteijn, I. van; Vaes, W.H.J.; Hermens, J.L.M.

    2003-01-01

    In the current study, the bioconcentration behavior and acute toxicity of two polycyclic musks, Tonalide® 7-acetyl-1,1,3,4,4,6,-hexamethyl-1,2,3,4,-tetrahydronaphthalene (AHTN) and Galaxolide® 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexa-methyl-cyclopenta[γ]-2- benzopyran (HHCB), were studied in two

  1. Toxicity assessment of pesticide triclosan by aquatic organisms and degradation studies.

    Science.gov (United States)

    Taştan, Burcu Ertit; Tekinay, Turgay; Çelik, Hatice Sena; Özdemir, Caner; Cakir, Dilara Nur

    2017-12-01

    Triclosan is considered as an important contaminant and is widely used in personal care products as an antimicrobial agent. This study demonstrates the biodegradation of triclosan by two freshwater microalgae and the acute toxicity of triclosan and 2,4-dichlorophenol. The effects of culture media and light on biodegradation of triclosan and the changing morphology of microalgae were systematically studied. Geitlerinema sp. and Chlorella sp. degraded 82.10% and 92.83% of 3.99 mg/L of triclosan at 10 days, respectively. The microalgal growth inhibition assay confirmed absence of toxic effects of triclosan on Chlorella sp., even at higher concentration (50 mg/L) after 72 h exposure. HPLC analysis showed that 2,4-dichlorophenol was produced as degradation product of triclosan by Geitlerinema sp. and Chlorella sp. This study proved to be beneficial to understand biodegradation and acute toxicity of triclosan by microalgae in order to provide aquatic environmental protection. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Incipient toxicity of lithium to freshwater organisms representing a salmonid habitat

    International Nuclear Information System (INIS)

    Emery, R.; Klopfer, D.C.; Skalski, J.R.

    1981-07-01

    Because the eventual development of fusion power reactors could increase the mining, use and disposal of lithium five-fold by the year 2000, potential effects from unusual amounts of lithium in aquatic environments were investigated. Freshwater oganisms representing a Pacific Northwest salmonid habitat were exposed to elevated conentrations of lithium. Nine parameters were used to determine the incipient toxicity of lithium to rainbow trout (Salmo gairdneri), insect larvae (Chironomus sp.), and Columbia River periphyton. All three groups of biota were incipiently sensitive to lithium at concentrations ranging between 0.1 and 1 mg/L. These results correspond with the incipient toxicity of beryllium, a chemically similar component of fusion reactor cores. A maximum lithium concentration of 0.01 mg/L occurs naturally in most freshwater environments (beryllium is rarer). Therefore, a concentration range of 0.01 to 0.1 mg/L may be regarded as approaching toxic concentrations when assessing the hazards of lithium in freshwaters

  3. The potential acute and chronic toxicity of cyfluthrin on the soil model organism, Eisenia fetida.

    Science.gov (United States)

    Li, Lingling; Yang, Da; Song, Yufang; Shi, Yi; Huang, Bin; Bitsch, Annette; Yan, Jun

    2017-10-01

    In this study, the acute (72h and 14 d) and chronic (28 d and 8 weeks) effects of cyfluthrin on earthworms were evaluated across different endpoints, which are mortality, growth, reproduction and enzyme activities. Cyfluthrin was rated as moderately toxic in 72-h filter paper test and low toxic in 14-day soil test. The exposure of earthworms to cyfluthrin-polluted soil for 8 weeks showed that growth of earthworms was inhibited by cyfluthrin, cocoon production and hatching were inhibited by 20-60mg/kg cyfluthrin. Moreover, 28-day soil test on the responses of enzymes associated with antioxidation and detoxification showed that the activities of catalase (CAT) and glutathione S- transferase (GST) were initially increased by cyfluthrin at 5-20mg/kg, but reduced at 30-60mg/kg, peroxidase (POD) was increased by 26-102% by cyfluthrin in the early period, except 5mg/kg on day 7, and ethoxyresorufin-O-deethylase (EROD) was increased by 29-335% by cyfluthrin after 3 days. Cyfluthrin degraded with a half-life of 24.8-34.8 d, showing the inconsistency between the continuous toxic responses of earthworms and degradation of cyfluthrin in soil. The variable responses of these indexes indicated that different level endpoints should be jointly considered for better evaluation of the environmental risk of contaminants in soil. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Supplementation of Nigella sativa fixed and essential oil mediates potassium bromate induced oxidative stress and multiple organ toxicity.

    Science.gov (United States)

    Sultan, Muhammad Tauseef; Butt, Masood Sadiq; Ahmad, Rabia Shabeer; Pasha, Imran; Ahmad, Atif Nisar; Qayyum, Mir Muhammad Nasir

    2012-01-01

    The plants and their functional ingredients hold potential to cure various maladies and number of plants hold therapeutic potential. The present research was designed study the health promoting potential of black cumin (Nigella sativa) fixed oil (BCFO) and essential oil (BCEO) against oxidative stress with special reference to multiple organ toxicity. For the purpose, thirty rats (Strain: Sprague Dawley) were procured and divided into three groups (10 rats/group). The groups were fed on their respective diets i.e. D1 (control), D2 (BCFO @ 4.0%) and D3 (BCEO @ 0.30%) for a period of 56 days. Mild oxidative stress was induced with the help of potassium bromate injection @ 45 mg/Kg body weight. Furthermore, the levels of cardiac and liver enzymes were assayed. The results indicated that oxidative stress increased the activities of cardiac and liver enzymes. However, supplementation of BCFO and BCEO was effective in reducing the abnormal values of enzymes. Elevated levels of lactate dehydrogenase (LDH), CPK and CPK-MB were reduced from 456 to 231, 176 to 122 and 45 to 36mg/dL, respectively. Similarly, liver enzymes were also reduced. However, the results revealed that BCEO supplementation @ 0.30% is more effectual in ameliorating the multiple organ toxicity in oxidative stressed animal modelling. In the nutshell, it can be assumed that black cumin essential oil is more effective in reducing the extent of potassium bromate induced multiple organ toxicity (cardiac and liver enzymes imbalance) that will ultimately helpful in reducing the extent of myocardial and liver necrosis.

  5. Organic chemistry of cosmic dusts for understanding an intra-relationship between meteorites and comets: Toward a new frontier of astromaterial science

    Science.gov (United States)

    Yabuta, Hikaru

    2012-07-01

    Organic matter in primitive solar system small bodies, such as meteorites, asteroids, and comets, provides us significant information on the origin and evolution of the early solar system. The achievements of the Stardust comet sample return mission [1] have enabled the comparable small body organic chemistry between comet 81P/Wild 2 and chondritic meteorites [2, 3]. The study of organic matter in interplanetary dust particles (IDPs) will play an important role for our further understanding of an intra-relationship among meteorites and comets, as some IDPs are of cometary origin. Historically, a number of isotopic and molecular compositions of organic matter in IDPs collected in stratosphere have been studied [4-7]. Recent new insights in the study of IDP organics is that, Ultracarbonaceous Antarctic micrometeorites (UCAMMs), unique extraterrestrial materials that represent large sizes of high carbon contents, have been first discovered by [8]. The mineralogical and isotopic investigations of UCAMMs by [9] have revealed the association of extreme deuterium-rich organic matter with both crystalline and amorphous silicates, which appears to be compatible to cometary origin. Yabuta et al. (2012) [10] has identified a highly nitrogen-rich but isotopically normal organic material from a UCAMM by X-ray absorption near edge structure (XANES) spectroscopy using a scanning transmission X-ray microscope (STXM). Such N-rich compositions have not been generally observed from chondritic organics and stratosphere IDPs, and are rather similar to those observed from several particles of Comet 81P/Wild 2. Aiming to investigate the intact compositions of organic matter in IDPs which those collected from stratosphere and Antarctica might have lost, the Japanese Astrobiology working group, Tanpopo, will be planning to collect the IDPs on the International Space Station from 2013. The mission has great advantages that collection of the pristine IDPs without atmospheric entry heating

  6. Effect of dissolved organic matter (DOM) of contrasting origins on Cu and Pb speciation and toxicity to Paracentrotus lividus larvae.

    Science.gov (United States)

    Sánchez-Marín, Paula; Santos-Echeandía, Juan; Nieto-Cid, Mar; Alvarez-Salgado, Xosé Antón; Beiras, Ricardo

    2010-01-31

    Water samples of contrasting origin, including natural seawater, two sediment elutriates and sewage-influenced seawater, were collected and obtained to examine the effect of the dissolved organic matter (DOM) present on metal bioavailability. The carbon content (DOC) and the optical properties (absorbance and fluorescence) of the coloured DOM fraction (CDOM) of these materials were determined. Cu and Pb complexation properties were measured by anodic stripping voltammetry (ASV) and the effect of DOM on Cu and Pb bioavailability was studied by means of the Paracentrotus lividus embryo-larval bioassay. Sediment elutriates and sewage-influenced water (1) were enriched 1.4-1.7 times in DOC; (2) absorbed and reemitted more light; and (3) presented higher Cu complexation capacities (L(Cu)) than the natural seawater used for their preparation. L(Cu) varied from 0.08 microM in natural seawater to 0.3 and 0.5 microM in sediment elutriates and sewage-influenced water, respectively. Differences in DOC, CDOM and Cu complexation capacities were reflected in Cu toxicity. DOM enriched samples presented a Cu EC(50) of 0.64 microM, significantly higher than the Cu EC(50) of natural and artificial seawater, which was 0.38 microM. The protecting effect of DOM on Cu toxicity greatly disappeared when the samples were irradiated with high intensity UV-light. Cu toxicity could be successfully predicted considering ASV-labile Cu concentrations in the samples. Pb complexation by DOM was only detected in the DOM-enriched samples and caused little effect on Pb EC(50). This effect was contrary for both elutriates: one elutriate reduced Pb toxicity in comparison with the control artificial seawater, while the other increased it. UV irradiation of the samples caused a marked increase in Pb toxicity, which correlated with the remaining DOC concentration. DOM parameters were related to Cu speciation and toxicity: good correlations were found between DOC and Cu EC(50), while L(Cu) correlated

  7. Effect of dissolved organic matter (DOM) of contrasting origins on Cu and Pb speciation and toxicity to Paracentrotus lividus larvae

    International Nuclear Information System (INIS)

    Sanchez-Marin, Paula; Santos-Echeandia, Juan; Nieto-Cid, Mar; Alvarez-Salgado, Xose Anton; Beiras, Ricardo

    2010-01-01

    Water samples of contrasting origin, including natural seawater, two sediment elutriates and sewage-influenced seawater, were collected and obtained to examine the effect of the dissolved organic matter (DOM) present on metal bioavailability. The carbon content (DOC) and the optical properties (absorbance and fluorescence) of the coloured DOM fraction (CDOM) of these materials were determined. Cu and Pb complexation properties were measured by anodic stripping voltammetry (ASV) and the effect of DOM on Cu and Pb bioavailability was studied by means of the Paracentrotus lividus embryo-larval bioassay. Sediment elutriates and sewage-influenced water (1) were enriched 1.4-1.7 times in DOC; (2) absorbed and reemitted more light; and (3) presented higher Cu complexation capacities (L Cu ) than the natural seawater used for their preparation. L Cu varied from 0.08 μM in natural seawater to 0.3 and 0.5 μM in sediment elutriates and sewage-influenced water, respectively. Differences in DOC, CDOM and Cu complexation capacities were reflected in Cu toxicity. DOM enriched samples presented a Cu EC 50 of 0.64 μM, significantly higher than the Cu EC 50 of natural and artificial seawater, which was 0.38 μM. The protecting effect of DOM on Cu toxicity greatly disappeared when the samples were irradiated with high intensity UV-light. Cu toxicity could be successfully predicted considering ASV-labile Cu concentrations in the samples. Pb complexation by DOM was only detected in the DOM-enriched samples and caused little effect on Pb EC 50 . This effect was contrary for both elutriates: one elutriate reduced Pb toxicity in comparison with the control artificial seawater, while the other increased it. UV irradiation of the samples caused a marked increase in Pb toxicity, which correlated with the remaining DOC concentration. DOM parameters were related to Cu speciation and toxicity: good correlations were found between DOC and Cu EC 50 , while L Cu correlated better with the

  8. Effect of dissolved organic matter (DOM) of contrasting origins on Cu and Pb speciation and toxicity to Paracentrotus lividus larvae

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Marin, Paula, E-mail: paulasanchez@uvigo.es [Laboratorio de Ecoloxia Marina (LEM), Universidade de Vigo, Campus Universitario, 36310 Vigo, Galicia (Spain); Santos-Echeandia, Juan; Nieto-Cid, Mar; Alvarez-Salgado, Xose Anton [Instituto de Investigacions Marinas, Consejo Superior de Investigaciones Cientificas (CSIC), Eduardo Cabello 6, 36208 Vigo, Galicia (Spain); Beiras, Ricardo [Laboratorio de Ecoloxia Marina (LEM), Universidade de Vigo, Campus Universitario, 36310 Vigo, Galicia (Spain)

    2010-01-31

    Water samples of contrasting origin, including natural seawater, two sediment elutriates and sewage-influenced seawater, were collected and obtained to examine the effect of the dissolved organic matter (DOM) present on metal bioavailability. The carbon content (DOC) and the optical properties (absorbance and fluorescence) of the coloured DOM fraction (CDOM) of these materials were determined. Cu and Pb complexation properties were measured by anodic stripping voltammetry (ASV) and the effect of DOM on Cu and Pb bioavailability was studied by means of the Paracentrotus lividus embryo-larval bioassay. Sediment elutriates and sewage-influenced water (1) were enriched 1.4-1.7 times in DOC; (2) absorbed and reemitted more light; and (3) presented higher Cu complexation capacities (L{sub Cu}) than the natural seawater used for their preparation. L{sub Cu} varied from 0.08 {mu}M in natural seawater to 0.3 and 0.5 {mu}M in sediment elutriates and sewage-influenced water, respectively. Differences in DOC, CDOM and Cu complexation capacities were reflected in Cu toxicity. DOM enriched samples presented a Cu EC{sub 50} of 0.64 {mu}M, significantly higher than the Cu EC{sub 50} of natural and artificial seawater, which was 0.38 {mu}M. The protecting effect of DOM on Cu toxicity greatly disappeared when the samples were irradiated with high intensity UV-light. Cu toxicity could be successfully predicted considering ASV-labile Cu concentrations in the samples. Pb complexation by DOM was only detected in the DOM-enriched samples and caused little effect on Pb EC{sub 50}. This effect was contrary for both elutriates: one elutriate reduced Pb toxicity in comparison with the control artificial seawater, while the other increased it. UV irradiation of the samples caused a marked increase in Pb toxicity, which correlated with the remaining DOC concentration. DOM parameters were related to Cu speciation and toxicity: good correlations were found between DOC and Cu EC{sub 50}, while L

  9. High-grade acute organ toxicity as positive prognostic factor in primary radio(chemo)therapy for locally advanced, inoperable head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, Hendrik Andreas; Bosch, Jan; Hennies, Steffen; Hess, Clemens F.; Christiansen, Hans [Dept. of Radiotherapy and Radiooncology, Univ. Medicine Goettingen (Germany); Jung, Klaus [Dept. of Medical Statistics, Univ. Medicine Goettingen (Germany); Overbeck, Tobias [Dept. of Haematology and Oncology, Univ. Medicine Goettingen (Germany); Matthias, Christoph; Roedel, Ralph M. [Dept. of Otorhinolaryngology, Univ. Medicine Goettingen (Germany)

    2010-05-15

    Purpose: to test for a possible correlation between high-grade acute organ toxicity during primary radio(chemo)therapy and treatment outcome in patients with locally advanced head and neck squamous cell carcinoma (HNSCC). Patients and methods: from 05/1994 to 01/2009, 216 HNSCC patients were treated with radio(chemo)therapy in primary approach. They received normofractionated (2 Gy/fraction) irradiation including associated nodal drainage sites to a cumulative dose of 70 Gy. 151 patients received additional concomitant chemotherapy (111 patients 5-fluorouracil/mitomycin C, 40 patients cisplatin-based). Toxicity during treatment was monitored weekly according to the Common Toxicity Criteria (CTC), and any toxicity grade CTC {>=} 3 of mucositis, dysphagia or skin reaction was assessed as high-grade acute organ toxicity for later analysis. Results: a statistically significant coherency between high-grade acute organ toxicity and overall survival as well as locoregional control was found: patients with CTC {>=} 3 acute organ toxicity had a 5-year overall survival rate of 4% compared to 8% in patients without (p < 0.01). Thereby, multivariate analyses revealed that the correlation was independent of other possible prognostic factors or factors that may influence treatment toxicity, especially concomitant chemotherapy and radiotherapy technique or treatment-planning procedure. Conclusion: these data indicate that normal tissue and tumor tissue may behave similarly with respect to treatment response, as high-grade acute organ toxicity during radio(chemo)therapy showed to be an independent prognostic marker in the own patient population. However, the authors are aware of the fact that a multivariate analysis in a retrospective study generally has statistical limitations. Therefore, their hypothesis should be further analyzed on biomolecular and clinical levels and other tumor entities in prospective trials. (orig.)

  10. [Roles of organic acid metabolism in plant adaptation to nutrient deficiency and aluminum toxicity stress].

    Science.gov (United States)

    Wang, Jianfei; Shen, Qirong

    2006-11-01

    Organic acids not only act as the intermediates in carbon metabolism, but also exert key roles in the plant adaptation to nutrient deficiency and metal stress and in the plant-microbe interactions at root-soil interface. From the viewpoint of plant nutrition, this paper reviewed the research progress on the formation and physiology of organic acids in plant, and their functions in nitrogen metabolism, phosphorus and iron uptake, aluminum tolerance, and soil ecology. New findings in the membrane transport of organic acids and the biotechnological manipulation of organic acids in transgenic model were also discussed. This novel perspectives of organic acid metabolism and its potential manipulation might present a possibility to understand the fundamental aspects of plant physiology, and lead to the new strategies to obtain crop varieties better adapted to environmental and metal stress.

  11. Multiple linear regression models for predicting chronic aluminum toxicity to freshwater aquatic organisms and developing water quality guidelines.

    Science.gov (United States)

    DeForest, David K; Brix, Kevin V; Tear, Lucinda M; Adams, William J

    2018-01-01

    The bioavailability of aluminum (Al) to freshwater aquatic organisms varies as a function of several water chemistry parameters, including pH, dissolved organic carbon (DOC), and water hardness. We evaluated the ability of multiple linear regression (MLR) models to predict chronic Al toxicity to a green alga (Pseudokirchneriella subcapitata), a cladoceran (Ceriodaphnia dubia), and a fish (Pimephales promelas) as a function of varying DOC, pH, and hardness conditions. The MLR models predicted toxicity values that were within a factor of 2 of observed values in 100% of the cases for P. subcapitata (10 and 20% effective concentrations [EC10s and EC20s]), 91% of the cases for C. dubia (EC10s and EC20s), and 95% (EC10s) and 91% (EC20s) of the cases for P. promelas. The MLR models were then applied to all species with Al toxicity data to derive species and genus sensitivity distributions that could be adjusted as a function of varying DOC, pH, and hardness conditions (the P. subcapitata model was applied to algae and macrophytes, the C. dubia model was applied to invertebrates, and the P. promelas model was applied to fish). Hazardous concentrations to 5% of the species or genera were then derived in 2 ways: 1) fitting a log-normal distribution to species-mean EC10s for all species (following the European Union methodology), and 2) fitting a triangular distribution to genus-mean EC20s for animals only (following the US Environmental Protection Agency methodology). Overall, MLR-based models provide a viable approach for deriving Al water quality guidelines that vary as a function of DOC, pH, and hardness conditions and are a significant improvement over bioavailability corrections based on single parameters. Environ Toxicol Chem 2018;37:80-90. © 2017 SETAC. © 2017 SETAC.

  12. Acute Toxicity Comparison of Single-Walled Carbon Nanotubes in Various Freshwater Organisms

    Directory of Open Access Journals (Sweden)

    Eun Kyung Sohn

    2015-01-01

    Full Text Available While the commercialization of single-walled carbon nanotubes (SWCNTs is rapidly expanding, the environmental impact of this nanomaterial is not well understood. Therefore, the present study evaluates the acute aquatic toxicity of SWCNTs towards two freshwater microalgae (Raphidocelis subcapitata and Chlorella vulgaris, a microcrustacean (Daphnia magna, and a fish (Oryzias latipes based on OECD test guidelines (201, 202, and 203. According to the results, the SWCNTs inhibited the growth of the algae R. subcapitata and C. vulgaris with a median effective concentration (EC50 of 29.99 and 30.96 mg/L, respectively, representing “acute category 3” in the Globally Harmonized System (GHS of classification and labeling of chemicals. Meanwhile, the acute toxicity test using O. latipes and D. magna did not show any mortality/immobilizing effects up to a concentration of 100.00 mg/L SWCNTs, indicating no hazard category in the GHS classification. In conclusion, SWCNTs were found to induce acute ecotoxicity in freshwater microalgae, yet not in D. magna and medaka fish.

  13. Toxicity of polyunsaturated aldehydes of diatoms to Indo-Pacific bioindicator organism Echinometra mathaei.

    Science.gov (United States)

    Sartori, Davide; Gaion, Andrea

    2016-01-01

    Although it is well known suitability of early developmental stages of sea urchin as recommended model for pollutant toxicity testing, little is known about the sensitivity of Indo-Pacific species Echinometra mathaei to polyunsaturated aldehydes. In this study, the effect of three short chain aldehydes, 2,4-decadienal (DD), 2,4-octadienal (OD) and 2,4-heptadienal (HD), normally found in many diatoms, such as Skeletonema costatum, Skeletonema marinoi and Thalassiosira rotula, was evaluated on larval development of E. mathaei embryos. Aldehydes affected larval development in a dose-dependent manner, in particular HD>OD>DD; the results of this study highlighted the higher sensitivity of this species toward aldehydes compared with data registered for other sea urchin species. In comparison with studies reported in the literature, contrasting results were observed during our tests; therefore, an increasing toxic effect was registered with decreasing the chain length of aldehydes. This work could provide new insights in the development of new toxicological assays toward most sensitive species.

  14. Attractive Toxic Sugar Bait (ATSB) For Control of Mosquitoes and Its Impact on Non-Target Organisms: A Review.

    Science.gov (United States)

    Fiorenzano, Jodi M; Koehler, Philip G; Xue, Rui-De

    2017-04-10

    Mosquito abatement programs contend with mosquito-borne diseases, insecticidal resistance, and environmental impacts to non-target organisms. However, chemical resources are limited to a few chemical classes with similar modes of action, which has led to insecticide resistance in mosquito populations. To develop a new tool for mosquito abatement programs that control mosquitoes while combating the issues of insecticidal resistance, and has low impacts of non-target organisms, novel methods of mosquito control, such as attractive toxic sugar baits (ATSBs), are being developed. Whereas insect baiting to dissuade a behavior, or induce mortality, is not a novel concept, as it was first introduced in writings from 77 AD, mosquito baiting through toxic sugar baits (TSBs) had been quickly developing over the last 60 years. This review addresses the current body of research of ATSB by providing an overview of active ingredients (toxins) include in TSBs, attractants combined in ATSB, lethal effects on mosquito adults and larvae, impact on non-target insects, and prospects for the use of ATSB.

  15. Engineering-scale dust control experiments

    International Nuclear Information System (INIS)

    Winberg, M.R.; Pawelko, R.J.; Jacobs, N.C.; Thompson, D.N.

    1990-12-01

    This report presents the results of engineering scale dust-control experiments relating to contamination control during handling of transuranic waste. These experiments focused on controlling dust during retrieval operations of buried waste where waste and soil are intimately mixed. Sources of dust generation during retrieval operations include digging, dumping, and vehicle traffic. Because contaminants are expected to attach to soil particles and move with the generated dust, control of the dust spread may be the key to contamination control. Dust control techniques examined in these experiments include the use of misting systems, soil fixatives, and dust suppression agents. The Dryfog Ultrasonic Misting Head, manufactured by Sonics, Incorporated, and ENTAC, an organic resin derived from tree sap manufactured by ENTAC Corporation, were tested. The results of the experiments include product performance and recommended application methods. 19 figs., 7 refs., 6 tabs

  16. The impact of sediment bioturbation by secondary organisms on metal bioavailability, bioaccumulation and toxicity to target organisms in benthic bioassays: Implications for sediment quality assessment

    International Nuclear Information System (INIS)

    Remaili, Timothy M.; Simpson, Stuart L.; Amato, Elvio D.; Spadaro, David A.; Jarolimek, Chad V.; Jolley, Dianne F.

    2016-01-01

    Bioturbation alters the properties of sediments and modifies contaminant bioavailability to benthic organisms. These naturally occurring disturbances are seldom considered during the assessment of sediment quality. We investigated how the presence (High bioturbation) and absence (Low bioturbation) of a strongly bioturbating amphipod within three different sediments influenced metal bioavailability, survival and bioaccumulation of metals to the bivalve Tellina deltoidalis. The concentrations of dissolved copper decreased and manganese increased with increased bioturbation. For copper a strong correlation was observed between increased bivalve survival (53–100%) and dissolved concentrations in the overlying water. Increased bioturbation intensity resulted in greater tissue concentrations for chromium and zinc in some test sediments. Overall, the results highlight the strong influence that the natural bioturbation activities from one organism may have on the risk contaminants pose to other organisms within the local environment. The characterisation of field-based exposure conditions concerning the biotic or abiotic resuspension of sediments and the rate of attenuation of released contaminants through dilution or readsorption may enable laboratory-based bioassay designs to be adapted to better match those of the assessed environment. - Highlights: • Bioturbation intensity modifies metal exposure and outcomes of sediment bioassays. • Sediment fluxes of Cu decrease and Mn and Zn increase with increased bioturbation. • Strong correlations between bioaccumulated and dissolved Cd, Cr, Pb, Zn, Cu and Ni. • Weak correlations between bioaccumulated and particulate metals. - This study investigated the impact of sediment bioturbation intensity on metal bioavailability and toxicity to aquatic organisms, and the implications of this to toxicity test design.

  17. Toxicity of natural mixtures of organic pollutants in temperate and polar marine phytoplankton

    KAUST Repository

    Echeveste, Pedro; Galbá n-Malagó n, Cristó bal; Dachs, Jordi; Berrojalbiz, Naiara; Agusti, Susana

    2016-01-01

    concentrations, viability of the cells, and growth and decay constants were monitored in response to addition of a range of concentrations of mixtures of organic pollutants obtained from seawater extracts. Almost all of the phytoplankton groups were significantly

  18. SITE - EMERGING TECHNOLOGIES: LASER INDUCED PHOTO- CHEMICAL OXIDATIVE DESTRUCTION OF TOXIC ORGANICS IN LEACHATES AND GROUNDWATERS

    Science.gov (United States)

    The technology described in this report has been developed under the Emerging Technology Program of the Superfund Innovative Technology Evaluation (SITE) Program to photochemically oxidize organic compounds in wastewater by applying ultraviolet radiation using an excimer laser. T...

  19. Combined effects of microplastics and chemical contaminants on the organ toxicity of zebrafish ( Danio rerio )

    DEFF Research Database (Denmark)

    Rainieri, Sandra; Conlledo, Nadia; Larsen, Bodil Katrine

    2018-01-01

    3 weeks of exposure fish were dissected and liver, intestine, muscular tissue and brain were extracted. After visual observation, evaluation of differential gene expression of some selected biomarker genes in liver, intestine and brain were carried out. Additionally, quantification of perfluorinated...... compounds in liver, brain, muscular tissue and intestine of some selected samples were performed. The feed supplemented with microplastics with sorbed contaminants produced the most evident effects especially on the liver. The results indicate that microplastics alone does not produce relevant effects......-contaminants of different nature in living organisms. Persistent organic pollutants and metals have been the co-contaminants majorly investigated in this field. The combined effect of microplastics and sorbed co-contaminants in aquatic organisms still needs to be properly understood. To address this, we have subjected...

  20. The influence of natural organic matter and aging on suspension stability in guideline toxicity testing of silver, zinc oxide, and titanium dioxide nanoparticles with Daphnia magna

    DEFF Research Database (Denmark)

    Cupi, Denisa; Hartmann, Nanna Isabella Bloch; Baun, Anders

    2015-01-01

    The present study investigated changes in suspension stability and ecotoxicity of engineered nanoparticles (ENPs) by addition of Suwannee River natural organic matter and aging of stock and test suspensions prior to testing. Acute toxicity tests of silver (Ag), zinc oxide (ZnO), and titanium...... not decrease toxicity significantly. Conversely, the presence of Suwannee River natural organic matter (NOM; 20mgL-1) completely alleviated Ag ENP toxicity in all testing scenarios and did not aid in stabilizing suspensions. In contrast, addition of Suwannee River NOM stabilized ZnO ENP suspensions and did...... in stock suspensions. The authors' results suggest that aging and presence of Suwannee River NOM are important parameters in standard toxicity testing of ENPs, which in some cases may aid in gaining better control over the exposure conditions but in other cases might contribute to agglomeration...

  1. Bioprinted 3D Primary Liver Tissues Allow Assessment of Organ-Level Response to Clinical Drug Induced Toxicity In Vitro.

    Directory of Open Access Journals (Sweden)

    Deborah G Nguyen

    Full Text Available Modeling clinically relevant tissue responses using cell models poses a significant challenge for drug development, in particular for drug induced liver injury (DILI. This is mainly because existing liver models lack longevity and tissue-level complexity which limits their utility in predictive toxicology. In this study, we established and characterized novel bioprinted human liver tissue mimetics comprised of patient-derived hepatocytes and non-parenchymal cells in a defined architecture. Scaffold-free assembly of different cell types in an in vivo-relevant architecture allowed for histologic analysis that revealed distinct intercellular hepatocyte junctions, CD31+ endothelial networks, and desmin positive, smooth muscle actin negative quiescent stellates. Unlike what was seen in 2D hepatocyte cultures, the tissues maintained levels of ATP, Albumin as well as expression and drug-induced enzyme activity of Cytochrome P450s over 4 weeks in culture. To assess the ability of the 3D liver cultures to model tissue-level DILI, dose responses of Trovafloxacin, a drug whose hepatotoxic potential could not be assessed by standard pre-clinical models, were compared to the structurally related non-toxic drug Levofloxacin. Trovafloxacin induced significant, dose-dependent toxicity at clinically relevant doses (≤ 4uM. Interestingly, Trovafloxacin toxicity was observed without lipopolysaccharide stimulation and in the absence of resident macrophages in contrast to earlier reports. Together, these results demonstrate that 3D bioprinted liver tissues can both effectively model DILI and distinguish between highly related compounds with differential profile. Thus, the combination of patient-derived primary cells with bioprinting technology here for the first time demonstrates superior performance in terms of mimicking human drug response in a known target organ at the tissue level.

  2. Lansoprazole Exacerbates Pemetrexed-Mediated Hematologic Toxicity by Competitive Inhibition of Renal Basolateral Human Organic Anion Transporter 3.

    Science.gov (United States)

    Ikemura, Kenji; Hamada, Yugo; Kaya, Chinatsu; Enokiya, Tomoyuki; Muraki, Yuichi; Nakahara, Hiroki; Fujimoto, Hajime; Kobayashi, Tetsu; Iwamoto, Takuya; Okuda, Masahiro

    2016-10-01

    Pemetrexed, a multitargeted antifolate, is eliminated by tubular secretion via human organic anion transporter 3 (hOAT3). Although proton pump inhibitors (PPIs) are frequently used in cancer patients, the drug interaction between PPIs and pemetrexed remains to be clarified. In this study, we examined the drug interaction between pemetrexed and PPIs in hOAT3-expressing cultured cells, and retrospectively analyzed the impact of PPIs on the development of hematologic toxicity in 108 patients who received pemetrexed and carboplatin treatment of nonsquamous non-small cell lung cancer for the first time between January 2011 and June 2015. We established that pemetrexed was transported via hOAT3 (Km = 68.3 ± 11.1 µM). Lansoprazole, rabeprazole, pantoprazole, esomeprazole, omeprazole, and vonoprazan inhibited hOAT3-mediated uptake of pemetrexed in a concentration-dependent manner. The inhibitory effect of lansoprazole was much greater than those of other PPIs and the apparent IC50 value of lansoprazole against pemetrexed transport via hOAT3 was 0.57 ± 0.17 µM. The inhibitory type of lansoprazole was competitive. In a retrospective study, multivariate analysis revealed that coadministration of lansoprazole, but not other PPIs, with pemetrexed and carboplatin was an independent risk factor significantly contributing to the development of hematologic toxicity (odds ratio: 10.004, P = 0.005). These findings demonstrated that coadministration of lansoprazole could exacerbate the hematologic toxicity associated with pemetrexed, at least in part, by competitive inhibition of hOAT3. Our results would aid clinicians to make decisions of coadministration drugs to avoid drug interaction-induced side effects for achievement of safe and appropriate chemotherapy with pemetrexed. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  3. Repeated subcutaneous administrations of krokodil causes skin necrosis and internal organs toxicity in Wistar rats: putative human implications.

    Science.gov (United States)

    Alves, Emanuele Amorim; Brandão, Pedro; Neves, João Filipe; Cravo, Sara Manuela; Soares, José Xavier; Grund, Jean-Paul C; Duarte, José Alberto; Afonso, Carlos M M; Pereira Netto, Annibal Duarte; Carvalho, Félix; Dinis-Oliveira, Ricardo Jorge

    2017-05-01

    "Krokodil" is the street name for an impure homemade drug mixture used as a cheap substitute for heroin, containing desomorphine as the main opioid. Abscesses, gangrene, thrombophlebitis, limb ulceration and amputations, jaw osteonecrosis, skin discoloration, ulcers, skin infections, and bleeding are some of the typical reported signs in humans. This study aimed to understand the toxicity of krokodil using Wistar male rats as experimental model. Animals were divided into seven groups and exposed subcutaneously to NaCl 0.9% (control), krokodil mixture free of psychotropic substances (blank krokodil), pharmaceutical grade desomorphine 1 mg/kg, and four different concentrations of krokodil (containing 0.125, 0.25, 0.5, and 1 mg/kg of desomorphine) synthesized accordingly to a "domestic" protocol followed by people who inject krokodil (PWIK). Daily injections for five consecutive days were performed, and animals were sacrificed 24 hr after the last administration. Biochemical and histological analysis were carried out. It was shown that the continuous use of krokodil may cause injury at the injection area, with formation of necrotic zones. The biochemical results evidenced alterations on cardiac and renal biomarkers of toxicity, namely, creatine kinase, creatine kinase-MB, and uric acid. Significant alteration in levels of reduced and oxidized glutathione on kidney and heart suggested that oxidative stress may be involved in krokodil-mediated toxicity. Cardiac congestion was the most relevant finding of continuous krokodil administration. These findings contribute notably to comprehension of the local and systemic toxicological impact of this complex drug mixture on major organs and will hopefully be useful for the development of appropriate treatment strategies towards the human toxicological effects of krokodil. Copyright © 2017 John Wiley & Sons, Ltd.

  4. Nematodes as sentinels of heavy metals and organic toxicants in the soil

    NARCIS (Netherlands)

    Ekschmitt, K.; Korthals, G.W.

    2006-01-01

    Field and laboratory research has repeatedly shown that free-living soil nematodes differ in their sensitivity to soil pollution. In this paper, we analyze whether nematode genera proved sensitive or tolerant toward heavy metals and organic pollutants in six long-term field experiments. We discuss

  5. Overview of the anaerobic toxicity caused by organic forest industry wastewater pollutants.

    NARCIS (Netherlands)

    Sierra-Alvarez, R.; Field, J.A.; Kortekaas, S.; Lettinga, G.

    1994-01-01

    Numerous types of organic environmental pollutants are encountered in forest industry effluents which potentially could inhibit consortia of anaerobic bacteria. The purpose of this study was to collect anaerobic bioassay data from the literature to better estimate the impact of these pollutants on

  6. Physicochemical and spectroscopic properties of natural organic matter (NOM) from various sources and implications for ameliorative effects on metal toxicity to aquatic biota

    Energy Technology Data Exchange (ETDEWEB)

    Al-Reasi, Hassan A.; Wood, Chris M. [Department of Biology, McMaster University, Hamilton, ON, L8S 4K1 (Canada); Smith, D. Scott, E-mail: ssmith@wlu.camailto [Department of Chemistry, Wilfrid Laurier University, Waterloo, ON, N2L 3C5 (Canada)

    2011-06-15

    Natural organic matter (NOM), expressed as dissolved organic carbon (DOC in mg C L{sup -1}), is an ubiquitous complexing agent in natural waters, and is now recognized as an important factor mitigating waterborne metal toxicity. However, the magnitude of the protective effect, judged by toxicity measures (e.g. LC50), varies substantially among different NOM sources even for similar DOC concentrations, implying a potential role of NOM physicochemical properties or quality of NOM. This review summarizes some key quality parameters for NOM samples, obtained by reverse osmosis, and by using correlation analyses, investigates their contribution to ameliorating metal toxicity towards aquatic biota. At comparable and environmentally realistic DOC levels, molecular spectroscopic characteristics (specific absorbance coefficient, SAC, and fluorescence index, FI) as well as concentrations of fluorescent fractions obtained from mathematical mixture resolution techniques (PARAFAC), explain considerable variability in the protective effects. NOM quality clearly influences the toxicity of copper (Cu) and lead (Pb). NOM quality may also influence the toxicity of silver (Ag), cadmium (Cd) and inorganic mercury (Hg), but as yet insufficient data are available to unequivocally support the latter correlations between toxicity reduction and NOM quality predictors. Cu binding capacities, protein-to-carbohydrate ratio, and lipophilicity, show insignificant correlation to the amelioration offered by NOMs, but these conclusions are based on data for Norwegian NOMs with very narrow ranges for the latter two parameters. Certainly, various NOMs alleviate metal toxicity differentially and therefore their quality measures should be considered in addition to their quantity.

  7. Toxicity of anti-fouling paints for use on ships and leisure boats to non-target organisms representing three trophic levels

    International Nuclear Information System (INIS)

    Karlsson, Jenny; Ytreberg, Erik; Eklund, Britta

    2010-01-01

    Leachates of anti-fouling paints for use on ships and leisure boats are examined for their ecotoxicological potential. Paint leachates were produced in both 7 per mille artificial (ASW) and natural seawater (NSW) and tested on three organisms, the bacterium Vibrio fischeri, the macroalga Ceramium tenuicorne, and the crustacean Nitocra spinipes. Generally, leaching in ASW produced a more toxic leachate and was up to 12 times more toxic to the organisms than was the corresponding NSW leachate. The toxicity could be explained by elevated concentrations of Cu and Zn in the ASW leachates. Of the NSW leachates, those from the ship paints were more toxic than those from leisure boat paints. The most toxic paint was the biocide-free leisure boat paint Micron Eco. This implies that substances other than added active agents (biocides) were responsible for the observed toxicity, which would not have been discovered without the use of biological tests. - Leachate from a biocide-free anti-fouling paint for leisure boat use was more toxic than leachates from ship paints.

  8. Critical issues in benzene toxicity and metabolism: the effect of interactions with other organic chemicals on risk assessment.

    Science.gov (United States)

    Medinsky, M A; Schlosser, P M; Bond, J A

    1994-11-01

    Benzene, an important industrial solvent, is also present in unleaded gasoline and cigarette smoke. The hematotoxic effects of benzene are well documented and include aplastic anemia and pancytopenia. Some individuals exposed repeatedly to cytotoxic concentrations of benzene develop acute myeloblastic anemia. It has been hypothesized that metabolism of benzene is required for its toxicity, although administration of no single benzene metabolite duplicates the toxicity of benzene. Several investigators have demonstrated that a combination of metabolites (hydroquinone and phenol, for example) is necessary to duplicate the hematotoxic effect of benzene. Enzymes implicated in the metabolic activation of benzene and its metabolites include the cytochrome P450 monooxygenases and myeloperoxidase. Since benzene and its hydroxylated metabolites (phenol, hydroquinone, and catechol) are substrates for the same cytochrome P450 enzymes, competitive interactions among the metabolites are possible. In vivo data on metabolite formation by mice exposed to various benzene concentrations are consistent with competitive inhibition of phenol oxidation by benzene. Other organic molecules that are substrates for cytochrome P450 can inhibit the metabolism of benzene. For example, toluene has been shown to inhibit the oxidation of benzene in a noncompetitive manner. Enzyme inducers, such as ethanol, can alter the target tissue dosimetry of benzene metabolites by inducing enzymes responsible for oxidation reactions involved in benzene metabolism. The dosimetry of benzene and its metabolites in the target tissue, bone marrow, depends on the balance of activation processes, such as enzymatic oxidation, and deactivation processes, like conjugation and excretion.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Drosophila embryos as model to assess cellular and developmental toxicity of multi-walled carbon nanotubes (MWCNT in living organisms.

    Directory of Open Access Journals (Sweden)

    Boyin Liu

    Full Text Available Different toxicity tests for carbon nanotubes (CNT have been developed to assess their impact on human health and on aquatic and terrestrial animal and plant life. We present a new model, the fruit fly Drosophila embryo offering the opportunity for rapid, inexpensive and detailed analysis of CNTs toxicity during embryonic development. We show that injected DiI labelled multi-walled carbon nanotubes (MWCNTs become incorporated into cells in early Drosophila embryos, allowing the study of the consequences of cellular uptake of CNTs on cell communication, tissue and organ formation in living embryos. Fluorescently labelled subcellular structures showed that MWCNTs remained cytoplasmic and were excluded from the nucleus. Analysis of developing ectodermal and neural stem cells in MWCNTs injected embryos revealed normal division patterns and differentiation capacity. However, an increase in cell death of ectodermal but not of neural stem cells was observed, indicating stem cell-specific vulnerability to MWCNT exposure. The ease of CNT embryo injections, the possibility of detailed morphological and genomic analysis and the low costs make Drosophila embryos a system of choice to assess potential developmental and cellular effects of CNTs and test their use in future CNT based new therapies including drug delivery.

  10. Amiodarone Hepatotoxicity with Absent Phospholipidosis and Steatosis: A Case Report and Review of Amiodarone Toxicity in Various Organs

    Directory of Open Access Journals (Sweden)

    Adela Cimic

    2013-01-01

    Full Text Available We present the first description of amiodarone toxicity in the liver without phospholipidosis or steatosis. In doing so, we will review the various effects of amiodarone toxicity in various organs. The patient is a young adult who had cardiac reconstruction as a child for transposition of the great vessels. A needle biopsy was taken due to elevated liver enzymes. Her ALT was 188 U/L (5–50 and AST 162 U/L (5–50. Alkaline phosphatase, total bilirubin, protein, and albumin were within normal limits. A serologic panel for viral hepatitis was negative. Antinuclear antibodies were positive at 260; however, anti-smooth muscle antibody and anti-mitochondrial antibody were negative. A protein electrophoresis showed a slightly elevated beta globulin 2 level of 0.5. Quantitative immunoglobulin levels were within normal limits except for a slightly elevated IgA 409 mg/dL (60–350. Liver ultrasound was unremarkable. The clinical differential was broad and included hepatic congestion along with autoimmune hepatitis. Sections showed only ballooned hepatocytes with Mallory-Denk bodies and perisinusoidal fibrosis. Arrival to the diagnosis was possible only after careful review of the patient’s medications. After discontinuation of amiodarone, the patient’s liver enzymes returned to normal levels.

  11. Is ozonation environmentally benign for reverse osmosis concentrate treatment? Four-level analysis on toxicity reduction based on organic matter fractionation.

    Science.gov (United States)

    Weng, Jingxia; Jia, Huichao; Wu, Bing; Pan, Bingcai

    2018-01-01

    Ozonation is a promising option to treat reverse osmosis concentrate (ROC). However, a systematic understanding and assessment of ozonation on toxicity reduction is insufficient. In this study, ROC sampled from a typical industrial park wastewater treatment plant of China was fractionated into hydrophobic acid (HOA), hydrophobic base (HOB), hydrophobic neutral (HON), and hydrophilic fraction (HI). Systematic bioassays covering bacteria, algae, fish, and human cell lines were conducted to reveal the role of ozonation in toxicity variation of the four ROC fractions. HOA in the raw ROC exhibited the highest toxicity, followed by HON and HI. Ozonation significantly reduced total organic carbon (TOC) and UV 254 values in HOA, HON, and HI and their toxicity except in HOB. Correlation analysis indicated that chemical data (TOC and UV 254 ) of HOA and HON correlated well with their toxicities; however, poor correlations were observed for HOB and HI, suggesting that a battery of toxicity assays is necessary. This study indicates that TOC reduction during ozonation could not fully reflect the toxicity issue, and toxicity assessment is required in conjunction with the chemical data to evaluate the effectiveness of ozonation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Enhancing Signal Output and Avoiding BOD/Toxicity Combined Shock Interference by Operating a Microbial Fuel Cell Sensor with an Optimized Background Concentration of Organic Matter

    Directory of Open Access Journals (Sweden)

    Yong Jiang

    2016-08-01

    Full Text Available In the monitoring of pollutants in an aquatic environment, it is important to preserve water quality safety. Among the available analysis methods, the microbial fuel cell (MFC sensor has recently been used as a sustainable and on-line electrochemical microbial biosensor for biochemical oxygen demand (BOD and toxicity, respectively. However, the effect of the background organic matter concentration on toxicity monitoring when using an MFC sensor is not clear and there is no effective strategy available to avoid the signal interference by the combined shock of BOD and toxicity. Thus, the signal interference by the combined shock of BOD and toxicity was systematically studied in this experiment. The background organic matter concentration was optimized in this study and it should be fixed at a high level of oversaturation for maximizing the signal output when the current change (ΔI is selected to correlate with the concentration of a toxic agent. When the inhibition ratio (IR is selected, on the other hand, it should be fixed as low as possible near the detection limit for maximizing the signal output. At least two MFC sensors operated with high and low organic matter concentrations and a response chart generated from pre-experiment data were both required to make qualitative distinctions of the four types of combined shock caused by a sudden change in BOD and toxicity.

  13. Lethal and sublethal endpoints observed for Artemia exposed to two reference toxicants and an ecotoxicological concern organic compound.

    Science.gov (United States)

    Manfra, Loredana; Canepa, Sara; Piazza, Veronica; Faimali, Marco

    2016-01-01

    Swimming speed alteration and mortality assays with the marine crustacean Artemia franciscana were carried out. EC50 and LC50 values after 24-48h exposures were calculated for two reference toxicants, copper sulphate pentahydrate (CuSO4·5H2O) and Sodium Dodecyl Sulphate (SDS), and an ecotoxicological concern organic compound, Diethylene Glycol (DEG). Different end-points have been evaluated, in order to point out their sensitivity levels. The swimming speed alteration (SSA) was compared to mortality values and also to the hatching rate inhibition (literature data). SSA resulted to be more sensitive than the mortality and with a sensitivity comparable to (or even higher than) the hatching rate endpoint. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Synthesis and adsorption behaviour of some organic and inorganic sorbents for some hazardous toxic elements

    International Nuclear Information System (INIS)

    El-Naggar, I.M.; Abou-Mesalam, M.M.; Abdel-Hamid, M.M.; Shady, S.A.; Aly, H.F.

    2000-01-01

    Poly (acrylamide-acrylic acid ) -zirconium phosphate p(AM-AA) -Zr p is a new organic resin and can be synthesized by gamma radiation induced polymerization of acrylic acid (AA) in the presence of poly acrylamide (PAM) using a template polymerization technique in the presence of zirconium oxychloride and then soaking in phosphoric acid. The obtained polymer shows an excellent thermal and chemical stabilities, high capacities measurements in addition to high selectivity behaviour to some hazardous heavy metals. In a comparative study for the previous organic resin, P(AM-AA)-Zr P with cerium(IV) antimonate (Ce Sb) and titanium (IV) antimonate (Ti Sb) as inorganic ion exchangers we can concluded that both of Ce Sb and Ti Sb have a greater selectivities to the hazardous heavy metals as compared with p(AM-AA) Zr P whereas the later has a higher capacity than Ce Sb and Ti Sb

  15. Combined effects of microplastics and chemical contaminants on the organ toxicity of zebrafish (Danio rerio).

    Science.gov (United States)

    Rainieri, Sandra; Conlledo, Nadia; Larsen, Bodil K; Granby, Kit; Barranco, Alejandro

    2018-04-01

    Microplastics contamination of the aquatic environment is considered a growing problem. The ingestion of microplastics has been documented for a variety of aquatic animals. Studies have shown the potential of microplastics to affect the bioavailability and uptake route of sorbed co-contaminants of different nature in living organisms. Persistent organic pollutants and metals have been the co-contaminants majorly investigated in this field. The combined effect of microplastics and sorbed co-contaminants in aquatic organisms still needs to be properly understood. To address this, we have subjected zebrafish to four different feeds: A) untreated feed; B) feed supplemented with microplastics (LD-PE 125-250µm of diameter); C) feed supplemented with 2% microplastics to which a mixture of PCBs, BFRs, PFCs and methylmercury were sorbed; and D) feed supplemented with the mixture of contaminants only. After 3 weeks of exposure fish were dissected and liver, intestine, muscular tissue and brain were extracted. After visual observation, evaluation of differential gene expression of some selected biomarker genes in liver, intestine and brain were carried out. Additionally, quantification of perfluorinated compounds in liver, brain, muscular tissue and intestine of some selected samples were performed. The feed supplemented with microplastics with sorbed contaminants produced the most evident effects especially on the liver. The results indicate that microplastics alone does not produce relevant effects on zebrafish in the experimental conditions tested; on the contrary, the combined effect of microplastics and sorbed contaminants altered significantly their organs homeostasis in a greater manner than the contaminants alone. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Environmental recovery by destruction of toxic organic compounds using electron beam accelerator

    International Nuclear Information System (INIS)

    Duarte, C.L; Sampa, M.H.O.; Rela, P.R.; Oikawa, H.

    2001-01-01

    The oxidation process has attracted many researchers because of the capacity to mineralise organic compounds. The most efficient oxidation is the use of OH radicals. There are various methods to generate OH radicals as the use of ozone, hydrogen peroxide and ultra-violet (AOP - Advanced Oxidation Process). The most simple and efficient method for generating OH radicals in situ is the interaction of ionizing radiation with water. The reactive species formed by the water irradiation are the reducing radical's solvated electron and H atoms and the oxidising radical hydroxyl OH. The reactive species will react with organic compounds in the water inducing their decomposition. The use of ionizing radiation has great ecological and technologies advantages, especially when compared to physical-chemical and biological methods. It degrades organic compounds, generating substances that are easily biodegraded without the necessity of adding chemical compounds. The purpose of the radiation treatment is the conversion of these substances to biodegradable compounds; sometimes the complete decomposition is not necessary for this conversion

  17. Review of organic nitrile incineration at the Toxic Substances Control Act Incinerator

    International Nuclear Information System (INIS)

    1997-10-01

    Lockheed Martin Energy Systems, Inc. (LMES) operates the East Tennessee Technology Park (ETTP), formerly called the Oak Ridge K-25 Site, where uranium was enriched under contract with the US Department of Energy (DOE). Currently, ETTP missions include environmental management, waste management (WM), and the development of new technologies. As part of its WM mission, ETTP operates the TSCA (Toxic Substances Control Act) Incinerator (TSCAI) for treatment of hazardous waste and polychlorinated biphenyls (PCBs) contaminated with low-level radioactivity. Beginning in the autumn of 1995, employees from diverse ETTP buildings and departments reported experiencing headaches, fatigue, depression, muscle aches, sleeplessness, and muscle tremors. These symptoms were judged by a physician in the ETTP Health Services Department to be consistent with chronic exposures to hydrogen cyanide (HCN). The National Institute for Occupational Safety and Health (NIOSH) was called in to perform a health hazard evaluation to ascertain whether the employees' illnesses were in fact caused by occupational exposure to HCN. The NIOSH evaluation found no patterns for employees' reported symptoms with respect to work location or department. NIOSH also conducted a comprehensive air sampling study, which did not detect airborne cyanides at the ETTP. Employees, however, expressed concerns that the burning of nitrile-bearing wastes at the TSCAI might have produced HCN as a combustion product. Therefore, LMES and DOE established a multidisciplinary team (TSCAI Technical Review Team) to make a more detailed review of the possibility that combustion of nitrile-bearing wastes at the TSCAI might have either released nitriles or created HCN as a product of incomplete combustion (PIC)

  18. Organic micropollutants (OMPs) in natural waters: Oxidation by UV/H2O2 treatment and toxicity assessment.

    Science.gov (United States)

    Rozas, Oscar; Vidal, Cristiane; Baeza, Carolina; Jardim, Wilson F; Rossner, Alfred; Mansilla, Héctor D

    2016-07-01

    Organic micropollutants (OMPs) are ubiquitous in natural waters even in places where the human activity is limited. The presence of OMPs in natural water sources for human consumption encourages the evaluation of different water purification technologies to ensure water quality. In this study, the Biobío river (Chile) was selected since the watershed includes urban settlements and economic activities (i.e. agriculture, forestry) that incorporate a variety of OMPs into the aquatic environment, such as pesticides, pharmaceuticals and personal care products. Atrazine (herbicide), caffeine (psychotropic), diclofenac (anti-inflammatory) and triclosan (antimicrobial) in Biobío river water and in different stages of a drinking and two wastewater treatment plants downstream Biobío river were determined using solid phase extraction (SPE) and liquid chromatography/tandem mass spectrometry (LC-MS/MS) and electrospray ionization (ESI). Quantification of these four compounds showed concentrations in the range of 8 ± 2 to 55 ± 10 ng L(-1) in Biobío river water, 11 ± 2 to 74 ± 21 ng L(-1) in the drinking water treatment plant, and 60 ± 10 to 15,000 ± 1300 ng L(-1) in the wastewater treatment plants. Caffeine was used as an indicator of wastewater discharges. Because conventional water treatment technologies are not designed to eliminate some emerging organic pollutants, alternative treatment processes, UV and UV/H2O2, were employed. The transformation of atrazine, carbamazepine (antiepileptic), diclofenac and triclosan was investigated at laboratory scale. Both processes were tested at different UV doses and the Biobío river water matrix effects were evaluated. Initial H2O2 concentration used was 10 mg L(-1). Results showed that, the transformation profile obtained using UV/H2O2 at UV doses up to 900 mJ cm(-2), followed the trend of diclofenac > triclosan > atrazine > carbamazepine. Furthermore acute toxicity tests with Daphnia magna were carried

  19. The chronic toxicity of molybdate to freshwater organisms. I. Generating reliable effects data

    Energy Technology Data Exchange (ETDEWEB)

    De Schamphelaere, K.A.C., E-mail: karel.deschamphelaere@Ugent.be [Laboratory of Environmental Toxicology and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University (Belgium); Stubblefield, W. [Oregon State University, Department of Environmental and Molecular Toxicology, 421 Weniger Hall, Corvallis, OR 97331 (United States); Rodriguez, P. [Centro de Investigacion Minera y Metalurgica (CIMM), Santiago (Chile); Vleminckx, K. [Department for Molecular Biomedical Research, Ghent University (Belgium); Janssen, C.R. [Laboratory of Environmental Toxicology and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University (Belgium)

    2010-10-15

    The European Union regulation on Registration, Evaluation, Authorization and Restriction of Chemical substances (REACH) (EC, 2006) requires the characterization of the chronic toxicity of many chemicals in the aquatic environment, including molybdate (MoO{sub 4}{sup 2-}). Our literature review on the ecotoxicity of molybdate revealed that a limited amount of reliable chronic no observed effect concentrations (NOECs) for the derivation of a predicted no-effect concentration (PNEC) existed. This paper presents the results of additional ecotoxicity experiments that were conducted in order to fulfill the requirements for the derivation of a PNEC by means of the scientifically most robust species sensitivity distribution (SSD) approach (also called the statistical extrapolation approach). Ten test species were chronically exposed to molybdate (added as sodium molybdate dihydrate, Na{sub 2}MoO{sub 4}.2H{sub 2}O) according to internationally accepted standard testing guidelines or equivalent. The 10% effective concentrations (EC10, expressed as measured dissolved molybdenum) for the most sensitive endpoint per species were 62.8-105.6 (mg Mo)/L for Daphnia magna (21 day-reproduction), 78.2 (mg Mo)/L for Ceriodaphnia dubia (7 day-reproduction), 61.2-366.2 (mg Mo)/L for the green alga Pseudokirchneriella subcapitata (72 h-growth rate), 193.6 (mg Mo)/L for the rotifer Brachionus calyciflorus (48 h-population growth rate), 121.4 (mg Mo)/L for the midge Chironomus riparius (14 day-growth), 211.3 (mg Mo)/L for the snail Lymnaea stagnalis (28 day-growth rate), 115.9 (mg Mo)/L for the frog Xenopus laevis (4 day-larval development), 241.5 (mg Mo)/L for the higher plant Lemna minor (7 day-growth rate), 39.3 (mg Mo)/L for the fathead minnow Pimephales promelas (34 day-dry weight/biomass), and 43.2 (mg Mo)/L for the rainbow trout Oncorhynchus mykiss (78 day-biomass). These effect concentrations are in line with the few reliable data currently available in the open literature. The data

  20. The chronic toxicity of molybdate to freshwater organisms. I. Generating reliable effects data

    International Nuclear Information System (INIS)

    De Schamphelaere, K.A.C.; Stubblefield, W.; Rodriguez, P.; Vleminckx, K.; Janssen, C.R.

    2010-01-01

    The European Union regulation on Registration, Evaluation, Authorization and Restriction of Chemical substances (REACH) (EC, 2006) requires the characterization of the chronic toxicity of many chemicals in the aquatic environment, including molybdate (MoO 4 2- ). Our literature review on the ecotoxicity of molybdate revealed that a limited amount of reliable chronic no observed effect concentrations (NOECs) for the derivation of a predicted no-effect concentration (PNEC) existed. This paper presents the results of additional ecotoxicity experiments that were conducted in order to fulfill the requirements for the derivation of a PNEC by means of the scientifically most robust species sensitivity distribution (SSD) approach (also called the statistical extrapolation approach). Ten test species were chronically exposed to molybdate (added as sodium molybdate dihydrate, Na 2 MoO 4 .2H 2 O) according to internationally accepted standard testing guidelines or equivalent. The 10% effective concentrations (EC10, expressed as measured dissolved molybdenum) for the most sensitive endpoint per species were 62.8-105.6 (mg Mo)/L for Daphnia magna (21 day-reproduction), 78.2 (mg Mo)/L for Ceriodaphnia dubia (7 day-reproduction), 61.2-366.2 (mg Mo)/L for the green alga Pseudokirchneriella subcapitata (72 h-growth rate), 193.6 (mg Mo)/L for the rotifer Brachionus calyciflorus (48 h-population growth rate), 121.4 (mg Mo)/L for the midge Chironomus riparius (14 day-growth), 211.3 (mg Mo)/L for the snail Lymnaea stagnalis (28 day-growth rate), 115.9 (mg Mo)/L for the frog Xenopus laevis (4 day-larval development), 241.5 (mg Mo)/L for the higher plant Lemna minor (7 day-growth rate), 39.3 (mg Mo)/L for the fathead minnow Pimephales promelas (34 day-dry weight/biomass), and 43.2 (mg Mo)/L for the rainbow trout Oncorhynchus mykiss (78 day-biomass). These effect concentrations are in line with the few reliable data currently available in the open literature. The data presented in this

  1. Dust collector

    Energy Technology Data Exchange (ETDEWEB)

    Sahourin, H.

    1988-03-22

    This invention relates to a dust collector or filter which may be used for large volume cleaning air for gases or for separating out industrial byproducts such as wood chips, sawdust, and shavings. It relies on filtration or separation using only a uniquely configured medium. A primary, but not exclusive, purpose of the invention is to enable very large throughput, capable of separating or filtering of gases containing up to three or more tons of byproduct with a minimum pressure-drop across the device. No preliminary cycloning, to remove major particulates is necessary. The collector generally comprises a continuous and integral filter medium which is suspended from a plurality of downwardly extending frames forming a series of separate elements having a triangular cross-section, each element being relatively wide at the top and narrow at the bottom to define, between adjacent elements, a divergent collecting space which is wide at the bottom. 11 figs.

  2. Dust Measurements in Tokamaks

    International Nuclear Information System (INIS)

    Rudakov, D; Yu, J; Boedo, J; Hollmann, E; Krasheninnikov, S; Moyer, R; Muller, S; Yu, A; Rosenberg, M; Smirnov, R; West, W; Boivin, R; Bray, B; Brooks, N; Hyatt, A; Wong, C; Fenstermacher, M; Groth, M; Lasnier, C; McLean, A; Stangeby, P; Ratynskaia, S; Roquemore, A; Skinner, C; Solomon, W M

    2008-01-01

    Dust production and accumulation impose safety and operational concerns for ITER. Diagnostics to monitor dust levels in the plasma as well as in-vessel dust inventory are currently being tested in a few tokamaks. Dust accumulation in ITER is likely to occur in hidden areas, e.g. between tiles and under divertor baffles. A novel electrostatic dust detector for monitoring dust in these regions has been developed and tested at PPPL. In DIII-D tokamak dust diagnostics include Mie scattering from Nd:YAG lasers, visible imaging, and spectroscopy. Laser scattering resolves size of particles between 0.16-1.6 (micro)m in diameter; the total dust content in the edge plasmas and trends in the dust production rates within this size range have been established. Individual dust particles are observed by visible imaging using fast-framing cameras, detecting dust particles of a few microns in diameter and larger. Dust velocities and trajectories can be determined in 2D with a single camera or 3D using multiple cameras, but determination of particle size is problematic. In order to calibrate diagnostics and benchmark dust dynamics modeling, pre-characterized carbon dust has been injected into the lower divertor of DIII-D. Injected dust is seen by cameras, and spectroscopic diagnostics observe an increase of carbon atomic, C2 dimer, and thermal continuum emissions from the injected dust. The latter observation can be used in the design of novel dust survey diagnostics

  3. A broad spectrum catalytic system for removal of toxic organics from water by deep oxidation. 1998 annual progress report

    International Nuclear Information System (INIS)

    Sen, A.

    1998-01-01

    'Toxic organics and polymers pose a serious threat to the environment, especially when they are present in aquatic systems. The objective of the research is the design of practical procedures for the removal and/or recycling of such pollutants by oxidation. This report summarizes the work performed in the first one and half years of a three year project. The authors had earlier described a catalytic system for the deep oxidation of toxic organics, such as benzene, phenol and substituted phenols, aliphatic and aromatic halogenated compounds, organophosphorus, and organosulfur compounds [1]. In this system, metallic palladium was found to catalyze the oxidation of the substrate by dioxygen in aqueous medium at 80--100 C in the presence of carbon monoxide. For all the substrates examined, deep oxidation to carbon monoxide, carbon dioxide, and water occurred in high yields, resulting in up to several hundred turnovers over a 24 h period. Because of a pressing need for new procedures for the destruction of chemical warfare agents, the authors have examined in detail the deep oxidation of appropriate model compounds containing phosphorus-carbon and sulfur-carbon bonds using the same catalytic system. The result is the first observation of the efficient catalytic oxidative cleavage of phosphorus-carbon and sulfur-carbon bonds under mild conditions, using dioxygen as the oxidant [2]. In addition to the achievements described above, they have unpublished results in several other areas. For example, they have investigated the possibility of using dihydrogen rather than carbon monoxide as a coreductant in the catalytic deep oxidation of substrates. Even more attractive from a practical standpoint is the possibility of using a mixture of carbon monoxide and dihydrogen (synthesis gas). Indeed, experiments indicated that it is possible to substitute carbon monoxide by dihydrogen or synthesis gas. Significantly, in the case of nitro compounds, the deep oxidation in fact proceeded

  4. Toxic effect of zinc nanoscale metal-organic frameworks on rat pheochromocytoma (PC12) cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Fei, E-mail: paper_mail@126.com [Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou 510515 (China); Yang, Baochun; Cai, Jing [Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou 510515 (China); Jiang, Yaodong [Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou 510515 (China); Xu, Jun [Department of Health Economy Administration, Nanfang Hospital, Southern Medical University, Guangzhou 510515 (China); Wang, Shan [Department of Pharmacy, Winthrop University Hospital, Mineola, NY 11501 (United States)

    2014-04-01

    Highlights: • Metal-organic frameworks (MOFs) represent a newborn family of hybrid materials. • MOFs have already shown promise in a number of biological applications. • The biological applications of MOFs raise concerns for potential cytotoxicity. • Substantial information about MOF's neurotoxicity is still quite scarce. • This study reveals for the first time the interaction of MOFs with neural cells. - Abstract: Metal-organic frameworks (MOFs) possess unique properties desirable for delivery of drugs and gaseous therapeutics, but their uncharacterized interactions with cells raise increasing concerns of their safety in such biomedical applications. We evaluated the adverse effects of zinc nanoscale MOFs on the cell morphology, cytoskeleton, cell viability and expression of neurotrophin signaling pathway-associated GAP-43 protein in rat pheochromocytoma PC12 cells. At the concentration of 25 μg/ml, zinc MOFs did not significantly affect morphology, viability and membrane integrity of the cells. But at higher concentrations (over 100 μg/ml), MOFs exhibited a time- and concentration-dependent cytotoxicity, indicating their entry into the cells via endocytosis where they release Zn{sup 2+} into the cytosol to cause increased intracellular concentration of Zn{sup 2+}. We demonstrated that the toxicity of MOFs was associated with a disrupted cellular zinc homeostasis and down-regulation of GAP-43 protein, which might be the underlying mechanism for the improved differentiation in PC12 cells. These findings highlight the importance of cytotoxic evaluation of the MOFs before their biomedical application.

  5. Toxic effect of zinc nanoscale metal-organic frameworks on rat pheochromocytoma (PC12) cells in vitro

    International Nuclear Information System (INIS)

    Ren, Fei; Yang, Baochun; Cai, Jing; Jiang, Yaodong; Xu, Jun; Wang, Shan

    2014-01-01

    Highlights: • Metal-organic frameworks (MOFs) represent a newborn family of hybrid materials. • MOFs have already shown promise in a number of biological applications. • The biological applications of MOFs raise concerns for potential cytotoxicity. • Substantial information about MOF's neurotoxicity is still quite scarce. • This study reveals for the first time the interaction of MOFs with neural cells. - Abstract: Metal-organic frameworks (MOFs) possess unique properties desirable for delivery of drugs and gaseous therapeutics, but their uncharacterized interactions with cells raise increasing concerns of their safety in such biomedical applications. We evaluated the adverse effects of zinc nanoscale MOFs on the cell morphology, cytoskeleton, cell viability and expression of neurotrophin signaling pathway-associated GAP-43 protein in rat pheochromocytoma PC12 cells. At the concentration of 25 μg/ml, zinc MOFs did not significantly affect morphology, viability and membrane integrity of the cells. But at higher concentrations (over 100 μg/ml), MOFs exhibited a time- and concentration-dependent cytotoxicity, indicating their entry into the cells via endocytosis where they release Zn 2+ into the cytosol to cause increased intracellular concentration of Zn 2+ . We demonstrated that the toxicity of MOFs was associated with a disrupted cellular zinc homeostasis and down-regulation of GAP-43 protein, which might be the underlying mechanism for the improved differentiation in PC12 cells. These findings highlight the importance of cytotoxic evaluation of the MOFs before their biomedical application

  6. Hair cell regeneration in the bullfrog vestibular otolith organs following aminoglycoside toxicity

    Science.gov (United States)

    Baird, Richard A.; Torres, M. A.; Schuff, N. R.

    1994-01-01

    Adult bullfrogs were given single intraotic injections of the aminoglycoside antibiotic gentamicin sulfate and sacrificed at postinjection times ranging from 0.5 to 9 days. The saccular and utricular maculae of normal and injected animals were examined in wholemount and cross-section. Intraotic 200 (mu) M gentamicin concentrations resulted in the uniform destruction of the hair bundles and, at later times, the cell bodies of saccular hair cells. In the utriculus, striolar hair cells were selectively damaged while extrastriolar hair cells were relatively unaffected. Regenerating hair cells, identified in sectioned material by their small cell bodies and short, well-formed hair bundles, were seen in the saccular and utricular maculae as early as 24-48 h postinjection. Immature versions of mature hair cell types in both otolith organs were recognized by the presence of absence of a bulbed kinocilia and the relative lengths of their kinocilia and longest sterocilia. Utricular hair cell types with kinocilia longer than their longest stereocilia were observed at earlier times than hair cell types with shorter kinocilia. In the same sacculus, the hair bundles of gentamicin-treated animals, even at 9 days postinjection, were significantly smaller than those of normal animals. The hair bundles of utricular hair cells, on the other hand, reached full maturity within the same time period.

  7. Technetium-99m-labeled deoxynivalenol from Fusarium mycotoxin alters organ toxicity in BALB/c mice by oral and intravenous route

    Directory of Open Access Journals (Sweden)

    P Chattopadhyay

    2012-01-01

    Full Text Available The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m (99m Tc-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma-scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of 99mTc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation.

  8. Technetium-99m-labeled deoxynivalenol from Fusarium mycotoxin alters organ toxicity in BALB/c mice by oral and intravenous route

    Energy Technology Data Exchange (ETDEWEB)

    Chattopadhyay, P; Pandey, A; Goyary, D; Chaurasia, A; Singh, L; Veer, V. [Division of Pharmaceutical Technology, Defence Research Laboratory, Assam (India); Department of Life Sciences, Defense Research Development and Organization, New Delhi (India)

    2012-07-01

    The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m ({sup 99m} Tc)-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of {sup 99m}Tc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation. (author)

  9. Technetium-99m-labeled deoxynivalenol from Fusarium mycotoxin alters organ toxicity in BALB/c mice by oral and intravenous route

    International Nuclear Information System (INIS)

    Chattopadhyay, P; Pandey, A; Goyary, D; Chaurasia, A; Singh, L; Veer, V.

    2012-01-01

    The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m ( 99m Tc)-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of 99m Tc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation. (author)

  10. Volatile organic compounds released from Microcystis flos-aquae under nitrogen sources and their toxic effects on Chlorella vulgaris.

    Science.gov (United States)

    Xu, Qinghuan; Yang, Lin; Yang, Wangting; Bai, Yan; Hou, Ping; Zhao, Jingxian; Zhou, Lv; Zuo, Zhaojiang

    2017-01-01

    Eutrophication promotes massive growth of cyanobacteria and algal blooms, which can poison other algae and reduce biodiversity. To investigate the differences in multiple nitrogen (N) sources in eutrophicated water on the emission of volatile organic compounds (VOCs) from cyanobacteria, and their toxic effects on other algal growth, we analyzed VOCs emitted from Microcystis flos-aquae with different types and concentrations of nitrogen, and determined the effects under Normal-N and Non-N conditions on Chlorella vulgaris. M. flos-aquae released 27, 22, 20, 27, 19, 25 and 17 compounds, respectively, with NaNO 3 , NaNO 2 , NH 4 Cl, urea, Ser, Lys and Arg as the sole N source. With the reduction in N amount, the emission of VOCs was increased markedly, and the most VOCs were found under Non-N condition. C. vulgaris cell propagation, photosynthetic pigment and Fv/Fm declined significantly following exposure to M. flos-aquae VOCs under Non-N condition, but not under Normal-N condition. When C. vulgaris cells were treated with two terpenoids, eucalyptol and limonene, the inhibitory effects were enhanced with increasing concentrations. Therefore, multiple N sources in eutrophicated water induce different VOC emissions from cyanobacteria, and reduction in N can cause nutrient competition, which can result in emissions of more VOCs. Those VOCs released from M. flos-aquae cells under Non-N for nutrient competition can inhibit other algal growth. Among those VOCs, eucalyptol and limonene are the major toxic agents. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Control of sand flies with attractive toxic sugar baits (ATSB) and potential impact on non-target organisms in Morocco.

    Science.gov (United States)

    Qualls, Whitney A; Müller, Gunter C; Khallaayoune, Khalid; Revay, Edita E; Zhioua, Elyes; Kravchenko, Vasiliy D; Arheart, Kristopher L; Xue, Rui-De; Schlein, Yosef; Hausmann, Axel; Kline, Daniel L; Beier, John C

    2015-02-08

    The persistence and geographical expansion of leishmaniasis is a major public health problem that requires the development of effective integrated vector management strategies for sand fly control. Moreover, these strategies must be economically and environmentally sustainable approaches that can be modified based on the current knowledge of sand fly vector behavior. The efficacy of using attractive toxic sugar baits (ATSB) for sand fly control and the potential impacts of ATSB on non-target organisms in Morocco was investigated. Sand fly field experiments were conducted in an agricultural area along the flood plain of the Ourika River. Six study sites (600 m x 600 m); three with "sugar rich" (with cactus hedges bearing countless ripe fruits) environments and three with "sugar poor" (green vegetation only suitable for plant tissue feeding) environments were selected to evaluate ATSB, containing the toxin, dinotefuran. ATSB applications were made either with bait stations or sprayed on non-flowering vegetation. Control sites were established in both sugar rich and sugar poor environments. Field studies evaluating feeding on vegetation treated with attractive (non-toxic) sugar baits (ASB) by non-target arthropods were conducted at both sites with red stained ASB applied to non-flowering vegetation, flowering vegetation, or on bait stations. At both the sites, a single application of ATSB either applied to vegetation or bait stations significantly reduced densities of both female and male sand flies (Phlebotomus papatasi and P. sergenti) for the five-week trial period. Sand fly populations were reduced by 82.8% and 76.9% at sugar poor sites having ATSB applied to vegetation or presented as a bait station, respectively and by 78.7% and 83.2%, respectively at sugar rich sites. The potential impact of ATSB on non-targets, if applied on green non-flowering vegetation and bait stations, was low for all non-target groups as only 1% and 0.7% were stained with non-toxic bait

  12. Toxicity of organic and inorganic nanoparticles to four species of white-rot fungi

    International Nuclear Information System (INIS)

    Galindo, T.P.S.; Pereira, R.; Freitas, A.C.; Santos-Rocha, T.A.P.; Rasteiro, M.G.; Antunes, F.; Rodrigues, D.; Soares, A.M.V.M.; Gonçalves, F.

    2013-01-01

    The rapid development of nanoparticles (NP) for industrial applications and large-volume manufacturing, with its subsequent release into the environment, raised the need to understand and characterize the potential effects of NP to biota. Accordingly, this work aimed to assess sublethal effects of five NP to the white-rot fungi species Trametes versicolor, Lentinus sajor caju, Pleurotus ostreatus, and Phanerochaete chrysosporium. Each species was exposed to serial dilutions of the following NP: organic-vesicles of SDS/DDAB and of Mo/NaO; gold-NP, quantum dot CdSe/ZnS, and Fe/Co. Fungi growth rate was monitored every day, and at the end of assay the mycelium from each replicate was collected to evaluate possible changes in its chemical composition. For all NP-suspensions the following parameters were characterized: hydrodynamic diameter, surface charge, aggregation index, zeta potential, and conductivity. All tested NP tended to aggregate when suspended in aqueous media. The obtained results showed that gold-NP, CdSe/ZnS, Mo/NaO, and SDS/DDAB significantly inhibited the growth of fungi with effects on the mycelium chemical composition. Among the tested NP, gold-NP and CdSe/ZnS were the ones exerting a higher effect on the four fungi. Finally to our knowledge, this is the first study reporting that different types of NP induce changes in the chemical composition of fungi mycelium. - Highlights: • Nanoparticles (NP) tend to aggregate when in aqueous suspensions. • Chemical composition revealed to be very important in the ecotoxicity of NP. • Observed effects suggested diversified modes of action of different NP. • White-rot fungi species exhibit great differences in their sensitivity to NP

  13. Toxicity of organic and inorganic nanoparticles to four species of white-rot fungi

    Energy Technology Data Exchange (ETDEWEB)

    Galindo, T.P.S., E-mail: pgalindo@ua.pt [CESAM, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Departamento de Biologia, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Pereira, R. [CESAM, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 4169-007 Porto (Portugal); Freitas, A.C.; Santos-Rocha, T.A.P. [CESAM, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Departamento de Química, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); ISEIT, Instituto Piaget Viseu, Estrada do Alto do Gaio, Lordosa, 3515-776 Viseu (Portugal); Rasteiro, M.G.; Antunes, F. [Department of Chemical Engineering, University of Coimbra, 3030-290 Coimbra (Portugal); Rodrigues, D. [CESAM, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Departamento de Química, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); ISEIT, Instituto Piaget Viseu, Estrada do Alto do Gaio, Lordosa, 3515-776 Viseu (Portugal); Soares, A.M.V.M.; Gonçalves, F. [CESAM, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Departamento de Biologia, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); and others

    2013-08-01

    The rapid development of nanoparticles (NP) for industrial applications and large-volume manufacturing, with its subsequent release into the environment, raised the need to understand and characterize the potential effects of NP to biota. Accordingly, this work aimed to assess sublethal effects of five NP to the white-rot fungi species Trametes versicolor, Lentinus sajor caju, Pleurotus ostreatus, and Phanerochaete chrysosporium. Each species was exposed to serial dilutions of the following NP: organic-vesicles of SDS/DDAB and of Mo/NaO; gold-NP, quantum dot CdSe/ZnS, and Fe/Co. Fungi growth rate was monitored every day, and at the end of assay the mycelium from each replicate was collected to evaluate possible changes in its chemical composition. For all NP-suspensions the following parameters were characterized: hydrodynamic diameter, surface charge, aggregation index, zeta potential, and conductivity. All tested NP tended to aggregate when suspended in aqueous media. The obtained results showed that gold-NP, CdSe/ZnS, Mo/NaO, and SDS/DDAB significantly inhibited the growth of fungi with effects on the mycelium chemical composition. Among the tested NP, gold-NP and CdSe/ZnS were the ones exerting a higher effect on the four fungi. Finally to our knowledge, this is the first study reporting that different types of NP induce changes in the chemical composition of fungi mycelium. - Highlights: • Nanoparticles (NP) tend to aggregate when in aqueous suspensions. • Chemical composition revealed to be very important in the ecotoxicity of NP. • Observed effects suggested diversified modes of action of different NP. • White-rot fungi species exhibit great differences in their sensitivity to NP.

  14. Sustainable Soil Washing: Shredded Card Filtration of Potentially Toxic Elements after Leaching from Soil Using Organic Acid Solutions

    Science.gov (United States)

    Ash, Christopher; Drábek, Ondřej; Tejnecký, Václav; Jehlička, Jan; Michon, Ninon; Borůvka, Luboš

    2016-01-01

    Shredded card (SC) was assessed for use as a sorbent of potentially toxic elements (PTE) carried from contaminated soil in various leachates (oxalic acid, formic acid, CaCl2, water). We further assessed SC for retention of PTE, using acidified water (pH 3.4). Vertical columns and a peristaltic pump were used to leach PTE from soils (O and A/B horizons) before passing through SC. Sorption onto SC was studied by comparing leachates, and by monitoring total PTE contents on SC before and after leaching. SC buffers against acidic soil conditions that promote metals solubility; considerable increases in solution pH (+4.49) were observed. Greatest differences in solution PTE content after leaching with/without SC occurred for Pb. In oxalic acid, As, Cd, Pb showed a high level of sorption (25, 15, and 58x more of the respective PTE in leachates without SC). In formic acid, Pb sorption was highly efficient (219x more Pb in leachate without SC). In water, only Pb showed high sorption (191x more Pb in leachate without SC). In desorption experiments, release of PTE from SC varied according to the source of PTE (organic/mineral soil), and type of solvent used. Arsenic was the PTE most readily leached in desorption experiments. Low As sorption from water was followed by fast release (70% As released from SC). A high rate of Cd sorption from organic acid solutions was followed by strong retention (~12% Cd desorption). SC also retained Pb after sorption from water, with subsequent losses of ≤8.5% of total bound Pb. The proposed use of this material is for the filtration of PTE from extract solution following soil washing. Low-molecular-mass organic acids offer a less destructive, biodegradable alternative to strong inorganic acids for soil washing. PMID:26900684

  15. Sustainable Soil Washing: Shredded Card Filtration of Potentially Toxic Elements after Leaching from Soil Using Organic Acid Solutions.

    Directory of Open Access Journals (Sweden)

    Christopher Ash

    Full Text Available Shredded card (SC was assessed for use as a sorbent of potentially toxic elements (PTE carried from contaminated soil in various leachates (oxalic acid, formic acid, CaCl2, water. We further assessed SC for retention of PTE, using acidified water (pH 3.4. Vertical columns and a peristaltic pump were used to leach PTE from soils (O and A/B horizons before passing through SC. Sorption onto SC was studied by comparing leachates, and by monitoring total PTE contents on SC before and after leaching. SC buffers against acidic soil conditions that promote metals solubility; considerable increases in solution pH (+4.49 were observed. Greatest differences in solution PTE content after leaching with/without SC occurred for Pb. In oxalic acid, As, Cd, Pb showed a high level of sorption (25, 15, and 58x more of the respective PTE in leachates without SC. In formic acid, Pb sorption was highly efficient (219x more Pb in leachate without SC. In water, only Pb showed high sorption (191x more Pb in leachate without SC. In desorption experiments, release of PTE from SC varied according to the source of PTE (organic/mineral soil, and type of solvent used. Arsenic was the PTE most readily leached in desorption experiments. Low As sorption from water was followed by fast release (70% As released from SC. A high rate of Cd sorption from organic acid solutions was followed by strong retention (~12% Cd desorption. SC also retained Pb after sorption from water, with subsequent losses of ≤8.5% of total bound Pb. The proposed use of this material is for the filtration of PTE from extract solution following soil washing. Low-molecular-mass organic acids offer a less destructive, biodegradable alternative to strong inorganic acids for soil washing.

  16. PERSPECTIVE: Dust, fertilization and sources

    Science.gov (United States)

    Remer, Lorraine A.

    2006-11-01

    fraction that arrives at another continent [2]. At the deposition end of the chain, it is still unclear how the limited minerals in the dust such as iron are released for uptake by organisms either on land or in the ocean. Not all dust deposited into oceans results in a phytoplankton bloom. The process requires a chemical pathway that mobilizes a fraction of the iron into soluble form. Meskhidze et al [3] show that phytoplankton blooms following dust transport from the Gobi desert in Asia into the Pacific ocean result in a phytoplankton bloom only if the dust is accompanied by high initial SO2-to-dust ratios, suggesting that sulfuric acid coatings on the dust particle mobilize the embedded iron in the dust for phytoplankton uptake. Quantifying transport, deposition and nutrient availability are the latter ends of a puzzle that must begin by identifying and quantifying dust emission at the sources. The emission process is complex at the microscale requiring the right conditions for saltation and bombardment, which makes identification and inclusion of sources in global transport models very difficult. The result is that estimates of annual global dust emissions range from 1000 to 3000 Tg per year [4]. Even as global estimates of dust emissions are uncertain, localizing the sources brings even greater uncertainty. It has been recognized for several years that dust sources are not uniformly distributed over the arid regions of the Earth, but are regulated to topographic lows associated with dried lake deposits [5]. Using aerosol information from satellites, a comprehensive map of the world's source regions shows sources localized to specific areas of the Earth's arid regions [6]. Still these maps suggest broad emission sources covering several degrees of latitude and longitude. In the paper by Koren and co-authors [7] appearing in this issue, one particular dust source, the Bodélé depression in Chad, is analyzed in detail. They find that the specific topography of the

  17. Choice of test organisms for determination of oil dispersant toxicity in marine waters. Auswahl von Testorganismen zur Bestimmung der Toxizitaet von Dispergatoren bei der Oelbekaempfung in marinen Gewaessern

    Energy Technology Data Exchange (ETDEWEB)

    Henke, G.A.

    1987-06-01

    Several marine organisms were investigated regarding their qualification for oil dispersant toxicity determination. Appropriate organisms were chosen for two different test procedures: Using mortality as a test criterion an acute toxicity test can be carried out very easy with larvae of the brine shrimp Artemia sp. The sensitivity for different dispersants ranges over several orders of magnitude. Another test indicator is the cell multiplication-inhibition test, conducted with the microalga Scrippsiella trochoidea, a representative of phytoplankton. The sensitivity for a common dispersant ranges a hundredfold higher than the acute toxicity test. Both test procedures are also practicable for other water-soluble substances, as well. One oil-spill dispersant efficiency test is proposed provisionally. (orig.) With 62 refs., 20 tabs., 11 figs.

  18. Composting of soils/sediments and sludges containing toxic organics including high energy explosives. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, R.C.; Kitchens, J.F.

    1993-07-01

    Laboratory and pilot-scale experimentation were conducted to evaluate composting as an on-site treatment technology to remediate soils contaminated with hazardous waste at DOE`s PANTEX Plant. Suspected contaminated sites within the PANTEX Plant were sampled and analyzed for explosives, other organics, and inorganic wastes. Soils in drainage ditches and playas at PANTEX Plant were found to be contaminated with low levels of explosives (including RDX, HMX, PETN and TATB). Additional sites previously used for solvent disposal were heavily contaminated with solvents and transformation products of the solvent, as well as explosives and by-products of explosives. Laboratory studies were conducted using {sup 14}C-labeled explosives and {sup 14}C-labeled diacetone alcohol contaminated soil loaded into horse manure/hay composts at three rates: 20, 30, and 40%(W/W). The composts were incubated for six weeks at approximately 60{degree}C with continuous aeration. All explosives degraded rapidly and were reduced to below detection limits within 3 weeks in the laboratory studies. {sup 14}C-degradates from {sup 14}C-RDX, {sup 14}C-HMX and {sup 14}C-TATB were largely limited to {sup 14}CO{sub 2} and unextracted residue in the compost. Volatile and non-volatile {sup 14}C-degradates were found to result from {sup 14}C-PETN breakdown, but these compounds were not identified. {sup 14}C-diacetone alcohol concentrations were significantly reduced during composting. However, most of the radioactivity was volatilized from the compost as non-{sup 14}CO{sub 2} degradates or as {sup 14}C-diacetone alcohol. Pilot scale composts loaded with explosives contaminated soil at 30% (W/W) with intermittent aeration were monitored over six weeks. Data from the pilot-scale study generally was in agreement with the laboratory studies. However, the {sup 14}C-labeled TATB degraded much faster than the unlabeled TATB. Some formulations of TATB may be more resistant to composting activity than others.

  19. REAL-TIME EMISSION CHARACTERIZATION OF ORGANIC AIR TOXIC POLLUTANTS DURING STEADY STATE AND TRANSIENT OPERATION OF A MEDIUM DUTY DIESEL ENGINE

    Science.gov (United States)

    An on-line monitoring method, jet resonance-enhanced multi-photon ionization (REMPI) with time-of-flight mass spectrometry (TOFMS) was used to measure emissions of organic air toxics from a medium-duty (60 kW)diesel generator during transient and steady state operations. Emission...

  20. A broad spectrum catalytic system for removal of toxic organics from water by deep oxidation. Annual progress report, September 15, 1996 - September 14, 1997

    International Nuclear Information System (INIS)

    Sen, A.

    1997-01-01

    'During the first year, the palladium-catalyzed deep oxidation of toxic organics by dioxygen in aqueous solution was examined in some detail. The research performed has established the viability of the catalytic system to effect the deep (and complete) oxidation of a very wide range of organic substrates under mild conditions. One significant observation was that chemical warfare agent models containing phosphorus-carbon and sulfur-carbon bonds could be eliminated by using this procedure.'

  1. Optimization of organic contaminant and toxicity testing analytical procedures for estimating the characteristics and environmental significance of natural gas processing plant waste sludges

    International Nuclear Information System (INIS)

    Novak, N.

    1990-10-01

    The Gas Plant Sludge Characterization Phase IIB program is a continuation of the Canadian Petroleum Association's (CPA) initiatives to characterize sludge generated at gas processing plants. The objectives of the Phase IIB project were to develop an effective procedure for screening waste sludges or centrifuge/leachate generated from sludge samples for volatile, solvent-soluble and water-soluble organics; verify the reproducibility of the three aquatic toxicity tests recommended as the battery of tests for determining the environmental significance of sludge centrifugates or leachates; assess the performance of two terrestrial toxicity tests in determining the environmental significance of whole sludge samples applied to soil; and to assess and discuss the reproducibility and cost-effectiveness of the sampling and analytical techniques proposed for the overall sludge characterization procedure. Conclusions and recommendations are provided for sludge collection, preparation and distribution, organic analyses, toxicity testing, project management, and procedure standardization. The three aquatic and two terrestrial toxicity tests proved effective in indicating the toxicity of complex mixtures. 27 refs., 3 figs., 59 tabs

  2. Treatment of heterogeneous mixed wastes: Enzyme degradation of cellulosic materials contaminated with hazardous organics and toxic and radioactive metals

    International Nuclear Information System (INIS)

    Vanderberg, L.A.; Foreman, T.M.; Attrep, M. Jr.; Brainard, J.R.; Sauer, N.

    1999-01-01

    The redirection and downsizing of the US Department of Energy's nuclear weapons complex requires that many facilities be decontaminated and decommissioned (D and D). At Los Alamos National Laboratory, much of the low-level radioactive, mixed, and hazardous/chemical waste volume handled by waste management operations was produced by D and D and environmental restoration activities. A combination of technologies--air stripping and biodegradation of volatile organics, enzymatic digestion of cellulosics, and metal ion extraction--was effective in treating a radiologically contaminated heterogeneous paint-stripping waste. Treatment of VOCs using a modified bioreactor avoided radioactive contamination of byproduct biomass and inhibition of biodegradation by toxic metal ions in the waste. Cellulase digestion of bulk cellulose minimized the final solid waste volume by 80%. Moreover, the residue passed TCLP for RCRA metals. Hazardous metals and radioactivity in byproduct sugar solutions were removed using polymer filtration, which employs a combination of water-soluble chelating polymers and ultrafiltration to separate and concentrate metal contaminants. Polymer filtration was used to concentrate RCRA metals and radioactivity into <5% of the original wastewater volume. Permeate solutions had no detectable radioactivity and were below RCRA-allowable discharge limits for Pb and Cr

  3. The contribution of oxidative stress to drug-induced organ toxicity and its detection in vitro and in vivo.

    Science.gov (United States)

    Pereira, Claudia V; Nadanaciva, Sashi; Oliveira, Paulo J; Will, Yvonne

    2012-02-01

    Nowadays the 'redox hypothesis' is based on the fact that thiol/disulfide couples such as glutathione (GSH/GSSG), cysteine (Cys/CySS) and thioredoxin ((Trx-(SH)2/Trx-SS)) are functionally organized in redox circuits controlled by glutathione pools, thioredoxins and other control nodes, and they are not in equilibrium relative to each other. Although ROS can be important intermediates of cellular signaling pathways, disturbances in the normal cellular redox can result in widespread damage to several cell components. Moreover, oxidative stress has been linked to a variety of age-related diseases. In recent years, oxidative stress has also been identified to contribute to drug-induced liver, heart, renal and brain toxicity. This review provides an overview of current in vitro and in vivo methods that can be deployed throughout the drug discovery process. In addition, animal models and noninvasive biomarkers are described. Reducing post-market drug withdrawals is essential for all pharmaceutical companies in a time of increased patient welfare and tight budgets. Predictive screens positioned early in the drug discovery process will help to reduce such liabilities. Although new and more efficient assays and models are being developed, the hunt for biomarkers and noninvasive techniques is still in progress.

  4. Excellent performance of copper based metal organic framework in adsorptive removal of toxic sulfonamide antibiotics from wastewater.

    Science.gov (United States)

    Azhar, Muhammad Rizwan; Abid, Hussein Rasool; Sun, Hongqi; Periasamy, Vijay; Tadé, Moses O; Wang, Shaobin

    2016-09-15

    The increasing concerns on toxicity of sulfonamide antibiotics in water require a prompt action to establish efficient wastewater treatment processes for their removal. In this study, adsorptive removal of a model sulfonamide antibiotic, sulfachloropyridazine (SCP), from wastewater is presented for the first time using a metal organic framework (MOF). A high surface area and thermally stable MOF, HKUST-1, was synthesized by a facile method. Batch adsorption studies were systematically carried out using HKUST-1. The high surface area and unsaturated metal sites resulted in a significant adsorption capacity with faster kinetics. Most of the SCP was removed in 15min and the kinetic data were best fitted with the pseudo second order model. Moreover, isothermal data were best fitted with the Langmuir model. The thermodynamic results showed that the adsorption is a spontaneous and endothermic process. The adsorption capacity of HKUST-1 is 384mg/g at 298K which is the highest compared to most of the materials for the antibiotics. The high adsorption capacity is attributed mainly to π-π stacking, hydrogen bonding and electrostatic interactions. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Concentrations of Semivolatile Organic Compounds Associated with African Dust Air Masses in Mali, Cape Verde, Trinidad and Tobago, and the U.S. Virgin Islands, 2001-2008

    Science.gov (United States)

    Garrison, Virginia H.; Foreman, William T.; Genualdi, Susan A.; Majewski, Michael S.; Mohammed, Azad; Simonich, Staci Massey

    2011-01-01

    Every year, billions of tons of fine particles are eroded from the surface of the Sahara Desert and the Sahel of West Africa, lifted into the atmosphere by convective storms, and transported thousands of kilometers downwind. Most of the dust is carried west to the Americas and the Caribbean in the Saharan Air Layer (SAL). Dust air masses predominately impact northern South America during the Northern Hemisphere winter and the Caribbean and Southeastern United States in summer. Dust concentrations vary considerably temporally and spatially. In a dust source region (Mali), concentrations range from background levels of 575 micrograms per cubic meter (mu/u g per m3) to 13,000 mu/u g per m3 when visibility degrades to a few meters (Gillies and others, 1996). In the Caribbean, concentrations of 200 to 600 mu/u g per m3 in the mid-Atlantic and Barbados (Prospero and others, 1981; Talbot and others, 1986), 3 to 20 mu/u g per m3 in the Caribbean (Prospero and Nees, 1986; Perry and others, 1997); and >100 mu/u g per m3 in the Virgin Islands (this dataset) have been reported during African dust conditions. Mean dust particle size decreases as the SAL traverses from West Africa to the Caribbean and Americas as a result of gravitational settling. Mean particle size reaching the Caribbean is <1 micrometer (mu/u m) (Perry and others, 1997), and even finer particles are carried into Central America, the Southeastern United States, and maritime Canada. Particles less than 2.5 mu/u m diameter (termed PM2.5) can be inhaled deeply into human lungs. A large body of literature has shown that increased PM2.5 concentrations are linked to increased cardiovascular/respiratory morbidity and mortality (for example, Dockery and others, 1993; Penn and others, 2005).

  6. Transfer of hydrophobic contaminants in urban runoff particles to benthic organisms estimated by an in vitro bioaccessibility test

    DEFF Research Database (Denmark)

    Nakajima, F.; Saito, K.; Isozaki, Y.

    2006-01-01

    An in vitro bioaccessibility test was applied for assessing the transfer of polycyclic aromatic hydrocarbons (PAHs) present in road dust, into benthic organisms living in a receiving water body. The road dust is supposed to be urban runoff particles under wet weather conditions. Sodium dodecyl...... sulfate (SDS) solution was used as a hypothetical gut fluid. Pyrene, fluoranthene and phenanthrene were the main PAH species in the SIDS extractable fraction of road dust, as well as the whole extract. Benzo(ghi)perylene showed relatively low concentrations in the SIDS extract in spite of a high...... concentration in the original dust. The PAH composition in benthic organisms (polychaetes) did not correspond with that of the surrounding sediment and the PAHs detected were also detected in high concentrations in the SDS extract of road dust. When testing the toxicity of the extracted contaminants...

  7. Gene Expression Profiling of Lung Tissue of Rats Exposed to Lunar Dust Particles

    Science.gov (United States)

    Zhang, Ye; Feiveson, Alan H.; Lam, Chiu-Wing; Kidane, Yared H.; Ploutz-Snyder Robert; Yeshitla, Samrawit; Zalesak, Selina M.; Scully, Robert R.; Wu, Honglu; James, John T.

    2014-01-01

    The purpose of the study is to analyze the dynamics of global gene expression changes in the lung tissue of rats exposed to lunar dust particles. Multiple pathways and transcription factors were identified using the Ingenuity Pathway Analysis tool, showing the potential networks of these signaling regulations involved in lunar dust-induced prolonged proflammatory response and toxicity. The data presented in this study, for the first time, explores the molecular mechanisms of lunar dust induced toxicity. This work contributes not only to the risk assessment for future space exploration, but also to the understanding of the dust-induced toxicity to humans on earth.

  8. Relationship of antioxidant and oxidative stress markers in different organs following copper toxicity in a rat model

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Vijay [Department of Neurology, Sanjay Gandhi Post Graduate Medical Sciences, Lucknow (India); Kalita, Jayantee, E-mail: jayanteek@yahoo.com [Department of Neurology, Sanjay Gandhi Post Graduate Medical Sciences, Lucknow (India); Bora, Himangsu K. [National Laboratory Animal Centre, CSIR-Central Drug Research Institute, Lucknow (India); Misra, Usha K. [Department of Neurology, Sanjay Gandhi Post Graduate Medical Sciences, Lucknow (India)

    2016-02-15

    Copper (Cu) at a higher level becomes toxic and it can catalyze the formation of highly reactive hydroxyl radical. We report the vulnerability of liver, kidney and brain to different dose of copper sulfate (CuSO{sub 4}) induced oxidative stress at different time duration. Fifty-four male Wistar rats (weight range = 205 ± 10 g) were equally divided into three groups. CuSO{sub 4} was administered orally to the experimental groups (Group-II and III) up to 90 days in a dose of 100 and 200 mg/Kg body weight per day. Saline water was given to the control group (Group-I). At the end of 30, 60 and 90 days of administration, neurobehavioral studies were done and six rats from each group were sacrificed. Their liver, kidney and brain tissues were subjected for Cu, glutathione (GSH), malondialdehyde (MDA) and total antioxidant capacity (TAC) assay. Blood urea nitrogen (BUN), serum creatinine, bilirubin and transaminases were measured. GSH, TAC and MDA levels were correlated with the markers of respective organ dysfunction. Administration of CuSO{sub 4} resulted in increased free Cu and MDA level, and decrease GSH and TAC levels in group-II and III compared with group-I. In experimental groups, the reduction in TAC and GSH levels was maximum in liver tissue followed by brain and kidney; whereas increase in MDA level was highest in liver followed by brain and kidney at 30, 60 and 90 days. TAC and GSH levels in the liver inversely correlated with serum transaminases and bilirubin, and tissue free Cu, and positively correlated with MDA levels. Free Cu level in kidney tissue and BUN inversely correlated with TAC and GSH, and positively with MDA level. Grip-strength, rotarod and Y-maze findings were inversely correlated with brain free Cu and MDA levels and positively with GSH and TAC levels. The oxidative stress was highest in liver followed by brain and kidney after oral CuSO{sub 4} exposure in a rat model. These levels correlated with the respective organ dysfunction and tissue

  9. Carbonaceous Components in the Comet Halley Dust

    Science.gov (United States)

    Fomenkova, M. N.; Chang, S.; Mukhin, L. M.

    1994-01-01

    Cometary grains containing large amounts of carbon and/or organic matter (CHON) were discovered by in situ measurements of comet Halley dust composition during VEGA and GIOTTO flyby missions. In this paper, we report the classification of these cometary, grains by means of cluster analysis, discuss the resulting compositional groups, and compare them with substances observed or hypothesized in meteorites, interplanetary dust particles, and the interstellar medium. Grains dominated by carbon and/or organic matter (CHON grains) represent approx. 22% of the total population of measured cometary dust particles. They, usually contain a minor abundance of rock-forming elements as well. Grains having organic material are relatively more abundant in the vicinity of the nucleus than in the outer regions of the coma, which suggests decomposition of the organics in the coma environment. The majority of comet Halley organic particles are multicomponent mixtures of carbon phases and organic compounds. Possibly, the cometary CHON grains may be related to kerogen material of an interstellar origin in carbonaceous meteorites. Pure carbon grains, hydrocarbons and polymers of cyanopolyynes, and multi-carbon monoxides are present in cometary dust as compositionally simple and distinctive components among a variety of others. There is no clear evidence of significant presence of pure formaldehyde or HCN polymers in Halley dust particles. The diversity of types of cometary organic compounds is consistent with the inter-stellar dust model of comets and probably reflects differences in composition of precursor dust. Preservation of this heterogeneity among submicron particles suggest the gentle formation of cometary, nucleus by aggregation of interstellar dust in the protosolar nebula without complete mixing or chemical homogenization at the submicron level.

  10. Characteristics of mineral dust impacting the Persian Gulf

    Science.gov (United States)

    Ahmady-Birgani, Hesam; McQueen, Kenneth G.; Mirnejad, Hassan

    2018-02-01

    It is generally assumed that severe dust events in western Iran could be responsible for elevated levels of toxic and radioactive elements in the region. Over a period of 5 months, from January 2012 to May 2012, dust particles in the size range PM10 (i.e. chemical compositions of dust and aerosol samples collected during the non-dusty periods and during two severe dust events. Results of ICP-MS analysis of components indicate that during dust events the concentrations of major elements such as Ca, Mg, Al and K increase relative to ambient conditions when Fe and trace elements such as Cu, Cr, Ni, Pb and Zn are in higher proportions. Toxic trace elements that are generally ascribed to human activities, including industrial and urban pollution, are thus proportionately more abundant in the dust under calm conditions than during dust events, when their concentration is diluted by more abundant mineral particles of quartz, calcite and clay. The variability of chemical species during two dust events, noted by tracking the dust plumes in satellite images, was also assessed and the results relate to two different source areas, namely northern Iraq and northwestern Syria.

  11. Critical dose and toxicity index of organs at risk in radiotherapy: Analyzing the calculated effects of modified dose fractionation in non–small cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Pedicini, Piernicola, E-mail: ppiern@libero.it [Service of Medical Physics, I.R.C.C.S. Regional Cancer Hospital C.R.O.B, Rionero in Vulture (Italy); Strigari, Lidia [Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome (Italy); Benassi, Marcello [Service of Medical Physics, Scientific Institute of Tumours of Romagna I.R.S.T., Meldola (Italy); Caivano, Rocchina [Service of Medical Physics, I.R.C.C.S. Regional Cancer Hospital C.R.O.B, Rionero in Vulture (Italy); Fiorentino, Alba [U.O. of Radiotherapy, I.R.C.C.S. Regional Cancer Hospital C.R.O.B., Rionero in Vulture (Italy); Nappi, Antonio [U.O. of Nuclear Medicine, I.R.C.C.S. Regional Cancer Hospital C.R.O.B., Rionero in Vulture (Italy); Salvatore, Marco [U.O. of Nuclear Medicine, I.R.C.C.S. SDN Foundation, Naples (Italy); Storto, Giovanni [U.O. of Nuclear Medicine, I.R.C.C.S. Regional Cancer Hospital C.R.O.B., Rionero in Vulture (Italy)

    2014-04-01

    To increase the efficacy of radiotherapy for non–small cell lung cancer (NSCLC), many schemes of dose fractionation were assessed by a new “toxicity index” (I), which allows one to choose the fractionation schedules that produce less toxic treatments. Thirty-two patients affected by non resectable NSCLC were treated by standard 3-dimensional conformal radiotherapy (3DCRT) with a strategy of limited treated volume. Computed tomography datasets were employed to re plan by simultaneous integrated boost intensity-modulated radiotherapy (IMRT). The dose distributions from plans were used to test various schemes of dose fractionation, in 3DCRT as well as in IMRT, by transforming the dose-volume histogram (DVH) into a biological equivalent DVH (BDVH) and by varying the overall treatment time. The BDVHs were obtained through the toxicity index, which was defined for each of the organs at risk (OAR) by a linear quadratic model keeping an equivalent radiobiological effect on the target volume. The less toxic fractionation consisted in a severe/moderate hyper fractionation for the volume including the primary tumor and lymph nodes, followed by a hypofractionation for the reduced volume of the primary tumor. The 3DCRT and IMRT resulted, respectively, in 4.7% and 4.3% of dose sparing for the spinal cord, without significant changes for the combined-lungs toxicity (p < 0.001). Schedules with reduced overall treatment time (accelerated fractionations) led to a 12.5% dose sparing for the spinal cord (7.5% in IMRT), 8.3% dose sparing for V{sub 20} in the combined lungs (5.5% in IMRT), and also significant dose sparing for all the other OARs (p < 0.001). The toxicity index allows to choose fractionation schedules with reduced toxicity for all the OARs and equivalent radiobiological effect for the tumor in 3DCRT, as well as in IMRT, treatments of NSCLC.

  12. LADEE LUNAR DUST EXPERIMENT

    Data.gov (United States)

    National Aeronautics and Space Administration — This archive bundle includes data taken by the Lunar Dust Experiment (LDEX) instrument aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft....

  13. Construction dust amelioration techniques.

    Science.gov (United States)

    2012-04-01

    Dust produced on seasonal road construction sites in Alaska is both a traffic safety and environmental concern. Dust emanating from : unpaved road surfaces during construction severely reduces visibility and impacts stopping sight distance, and contr...

  14. On Dust Charging Equation

    OpenAIRE

    Tsintsadze, Nodar L.; Tsintsadze, Levan N.

    2008-01-01

    A general derivation of the charging equation of a dust grain is presented, and indicated where and when it can be used. A problem of linear fluctuations of charges on the surface of the dust grain is discussed.

  15. Kuiper Belt Dust Grains as a Source of Interplanetary Dust Particles

    Science.gov (United States)

    Liou, Jer-Chyi; Zook, Herbert A.; Dermott, Stanley F.

    1996-01-01

    The recent discovery of the so-called Kuiper belt objects has prompted the idea that these objects produce dust grains that may contribute significantly to the interplanetary dust population. In this paper, the orbital evolution of dust grains, of diameters 1 to 9 microns, that originate in the region of the Kuiper belt is studied by means of direct numerical integration. Gravitational forces of the Sun and planets, solar radiation pressure, as well as Poynting-Robertson drag and solar wind drag are included. The interactions between charged dust grains and solar magnetic field are not considered in the model. Because of the effects of drag forces, small dust grains will spiral toward the Sun once they are released from their large parent bodies. This motion leads dust grains to pass by planets as well as encounter numerous mean motion resonances associated with planets. Our results show that about 80% of the Kuiper belt grains are ejected from the Solar System by the giant planets, while the remaining 20% of the grains evolve all the way to the Sun. Surprisingly, the latter dust grains have small orbital eccentricities and inclinations when they cross the orbit of the Earth. This makes them behave more like asteroidal than cometary-type dust particles. This also enhances their chances of being captured by the Earth and makes them a possible source of the collected interplanetary dust particles; in particular, they represent a possible source that brings primitive/organic materials from the outer Solar System to the Earth. When collisions with interstellar dust grains are considered, however, Kuiper belt dust grains around 9 microns appear likely to be collisionally shattered before they can evolve toward the inner part of the Solar System. The collision destruction can be applied to Kuiper belt grains up to about 50 microns. Therefore, Kuiper belt dust grains within this range may not be a significant part of the interplanetary dust complex in the inner Solar

  16. Minimal levels of ultraviolet light enhance the toxicity of TiO2 nanoparticles to two representative organisms of aquatic systems

    Science.gov (United States)

    Clemente, Z.; Castro, V. L.; Jonsson, C. M.; Fraceto, L. F.

    2014-08-01

    A number of studies have been published concerning the potential ecotoxicological risks of titanium dioxide nanoparticles (nano-TiO2), but the results still remain inconclusive. The characteristics of the diverse types of nano-TiO2 must be considered in order to establish experimental models to study their toxicity. TiO2 has important photocatalytic properties, and its photoactivation occurs in the ultraviolet (UV) range. The aim of this study was to investigate the toxicity of nano-TiO2 to indicators organisms of freshwater and saline aquatic systems, under different illumination conditions (visible light, with or without UV light). Daphnia similis and Artemia salina were co-exposed to a sublethal dose of UV light and different concentrations of nano-TiO2 in the form of anatase (TA) or an anatase/rutile mixture (TM). Both products were considered practically non-toxic under visible light to D. similis and A. salina (EC5048h > 100 mg/L). Exposure to nano-TiO2 under visible and UV light enhanced the toxicity of both products. In the case of D. similis, TM was more toxic than TA, showing values of EC5048h = 60.16 and 750.55 mg/L, respectively. A. salina was more sensitive than D. similis, with EC5048h = 4 mg/L for both products. Measurements were made of the growth rates of exposed organisms, together with biomarkers of oxidative stress and metabolism. The results showed that the effects of nano-TiO2 depended on the organism, exposure time, crystal phase, and illumination conditions, and emphasized the need for a full characterization of nanoparticles and their behavior when studying nanotoxicity.

  17. Physics of interstellar dust

    CERN Document Server

    Krugel, Endrik

    2002-01-01

    The dielectric permeability; How to evaluate grain cross sections; Very small and very big particles; Case studies of Mie calculus; Particle statistics; The radiative transition probability; Structure and composition of dust; Dust radiation; Dust and its environment; Polarization; Grain alignment; PAHs and spectral features of dust; Radiative transport; Diffuse matter in the Milky Way; Stars and their formation; Emission from young stars. Appendices Mathematical formulae; List of symbols.

  18. Dust as a surfactant

    International Nuclear Information System (INIS)

    Ignatov, A M; Schram, P P J M; Trigger, S A

    2003-01-01

    We argue that dust immersed in a plasma sheath acts as a surfactant. By considering the momentum balance in a plasma sheath, we evaluate the dependence of the plasma surface pressure on the dust density. It is shown that the dust may reduce the surface pressure, giving rise to a sufficiently strong tangential force. The latter is capable of confining the dust layer inside the sheath in the direction perpendicular to the ion flow

  19. Microplate Ames MPF™ test use in assessment of mutagenic properties of dust pollution

    Directory of Open Access Journals (Sweden)

    Agnieszka Kozłowska

    2012-09-01

    Full Text Available Background: Highly industrialized Upper Silesia Region is particularly polluted by both anthropogenic and natural airborne particulate matters, which may lead to negative health effects in human. Materials and methods: The aim of the study was to assess the mutagenic properties of dust extracts which were collected in six cities in the Silesian Voivodeship. Dust samples were collected on glass fiber filters by the aspirator with air flow ca. 1 m3/min. Extraction of pollution was carried out using dichlorometane. The extracted samples were dissolved in dimethylsulfoxide (DMSO. The mutagenic properties were assessed using microplate Ames assay MPFTM with the use of bacteria Salmonella typhimurium strain TA98 and TA100. Results: In microplate Ames assay MPFTM there was observed a linear dose-response relationship in both metabolic variants of TA98 strain. Similar relationship was observed for TA100 strain with metabolic activation (S9. Mutagenic activity (AM of 100% extracts for TA98 strain in both metabolic variants (S9 exceeded 2, what indicate highly mutagenic effects of dust extracts. There was no mutagenic activity observed in the assay with TA100 (S9, AM 1. In the variant with exogenous metabolic activation (S9 in TA100 strain AM values ranged from AM1,160,15 to AM9,671,02. Mutagenic activity varied between different cities. Conclusions: The study demonstrated that microplate Ames assay MPFTM is fast and complex method of assessing the mutagenic properties of dust pollution, which exert toxic effect on organisms. The use of microplate Ames assay MPFTM together with chemical analyses of air dust pollution may evaluate the level of exposure in the environment and enable to perform health risk assessment in populations exposed to mutagenic, toxic and cytotoxic substances.

  20. Effect of Soil Filtration and Ozonation in the Change of Baseline Toxicity in Wastewater Spiked with Organic Micro-pollutants

    KAUST Repository

    Gan, Alexander

    2012-01-01

    Bioassays for baseline toxicity, which measure toxicants’ non-specific effects, have been shown in previous studies to effectively correlate with the increased presence of pharmaceuticals, personal care products, endocrine-disrupting compounds

  1. Toxicity and bioaccumulation of xenobiotic organic compounds in the presence of aqueous suspensions of aggregates of nano-C60

    DEFF Research Database (Denmark)

    Baun, Anders; Sørensen, Sara Nørgaard; Rasmussen, R.F.

    2008-01-01

    The potential of C60-nanoparticles (Buckminster fullerenes) as contaminant carriers in aqueous systems was studied in a series of toxicity tests with algae (Pseudokirchneriella subcapitata) and crustaceans (Daphnia magna). Four common environmental contaminants (atrazine, methyl parathion, pentac...

  2. Critical issues in benzene toxicity and metabolism: the effect of interactions with other organic chemicals on risk assessment.

    OpenAIRE

    Medinsky, M A; Schlosser, P M; Bond, J A

    1994-01-01

    Benzene, an important industrial solvent, is also present in unleaded gasoline and cigarette smoke. The hematotoxic effects of benzene are well documented and include aplastic anemia and pancytopenia. Some individuals exposed repeatedly to cytotoxic concentrations of benzene develop acute myeloblastic anemia. It has been hypothesized that metabolism of benzene is required for its toxicity, although administration of no single benzene metabolite duplicates the toxicity of benzene. Several inve...

  3. Quality of Life and Toxicity after SBRT for Organ-Confined Prostate Cancer, a Seven Year Study

    Directory of Open Access Journals (Sweden)

    Alan Jay Katz

    2014-10-01

    Full Text Available Objectives: Stereotactic body radiation therapy (SBRT yields excellent disease control for lowandintermediate-risk prostate cancer by delivering high doses of radiation in a small number offractions. Our report presents a 7-year update on treatment toxicity and quality of life (QOLfrom 515 patients treated with prostate SBRT.Methods: From 2006 to 2009, 515 patients with clinically localized, low-, intermediate- andhigh-risk prostate cancer were treated with SBRT using Cyberknife technology. Treatmentconsisted of 35 to 36.25 Gy in 5 fractions. Seventy-two patients received hormone therapy.Toxicity was assessed at each follow up visit using the Expanded Prostate Cancer IndexComposite (EPIC questionnaire and the Radiation Therapy Oncology Group (RTOG urinaryand rectal toxicity scale.Results: Median follow up was 72 months. The actuarial 7-year freedom from biochemicalfailure was 95.8%, 89.3% and 68.5% for low-, intermediate- and high-risk groups, respectively(p < 0.001. No patients experienced acute Grade III or IV acute complications. Fewer than 5%of patients had any acute Grade II urinary or rectal toxicity. Late toxicity was low, with Grade IIrectal and urinary toxicity of 4% and 9.1%, respectively, and Grade III urinary toxicity of 1.7%.Mean EPIC urinary and bowel QOL declined at 1 month post-treatment, returned to baseline by2 years and remained stable thereafter. EPIC sexual QOL declined by 23% at 6-12 months andremained stable afterwards. Of patients potent at baseline evaluation, 67% remained potent atlast follow-up.Conclusions: This study suggests that SBRT, when administered to doses of 35 to 36.25 Gy, isefficacious and safe. With long-term follow up in our large patient cohort, we continue to findlow rates of late toxicity and excellent rates of biochemical control.

  4. The effects of salinity, pH, and dissolved organic matter on acute copper toxicity to the rotifer, Brachionus plicatilis ("L" strain).

    Science.gov (United States)

    Arnold, W R; Diamond, R L; Smith, D S

    2010-08-01

    This paper presents data from original research for use in the development of a marine biotic ligand model and, ultimately, copper criteria for the protection of estuarine and marine organisms and their uses. Ten 48-h static acute (unfed) copper toxicity tests using the euryhaline rotifer Brachionus plicatilis ("L" strain) were performed to assess the effects of salinity, pH, and dissolved organic matter (measured as dissolved organic carbon; DOC) on median lethal dissolved copper concentrations (LC50). Reconstituted and natural saltwater samples were tested at seven salinities (6, 11, 13, 15, 20, 24, and 29 g/L), over a pH range of 6.8-8.6 and a range of dissolved organic carbon of <0.5-4.1 mg C/L. Water chemistry analyses (alkalinity, calcium, chloride, DOC, hardness, magnesium, potassium, sodium, salinity, and temperature) are presented for input parameters to the biotic ligand model. In stepwise multiple regression analysis of experimental results where salinity, pH, and DOC concentrations varied, copper toxicity was significantly related only to the dissolved organic matter content (pH and salinity not statistically retained; alpha=0.05). The relationship of the 48-h dissolved copper LC50 values and dissolved organic carbon concentrations was LC50 (microg Cu/L)=27.1xDOC (mg C/L)1.25; r2=0.94.

  5. Lunar Dust Separation for Toxicology Studies

    Science.gov (United States)

    Cooper, Bonnie L.; McKay, D. S.; Riofrio, L. M.; Taylor, L. A.; Gonzalex, C. P.

    2010-01-01

    During the Apollo missions, crewmembers were briefly exposed to dust in the lunar module, brought in after extravehicular activity. When the lunar ascent module returned to micro-gravity, the dust that had settled on the floor now floated into the air, causing eye discomfort and occasional respiratory symptoms. Because our goal is to set an exposure standard for 6 months of episodic exposure to lunar dust for crew on the lunar surface, these brief exposures of a few days are not conclusive. Based on experience with industrial minerals such as sandblasting quartz, an exposure of several months may cause serious damage, while a short exposure may cause none. The detailed characteristics of sub-micrometer lunar dust are only poorly known, and this is the size range of particles that are of greatest concern. We have developed a method for extracting respirable dust (<2.5 micron) from Apollo lunar soils. This method meets stringent requirements that the soil must be kept dry, exposed only to pure nitrogen, and must conserve and recover the maximum amount of both respirable dust and coarser soil. In addition, we have developed a method for grinding coarser lunar soil to produce sufficient respirable soil for animal toxicity testing while preserving the freshly exposed grain surfaces in a pristine state.

  6. Some biochemical characteristics of a toxic substance isolated from organs of lethally irradiated animals in the course of the intestinal syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Meter, J D; Sirota, N S [Tsentral' nyj Nauchno-Issledovatel' skij Rentgeno-Radiologicheskij Inst., Leningrad (USSR)

    1976-05-01

    A toxic substance isolated from organs of lethally irradiated (1300 rads) animals in the period when intestinal syndrome has developed is classified according to the parameters under study (namely, the molecular weight, UV-absorption curve, extinction coefficient, specific monosaccharides, the presence and percentage of KDA, etc.) as lipopolysaccharide of Escherichia coli, the main inhabitant of the gastroenteric tract of mice. That endotoxins (sensitivity to which is increased in this period of radiation sickness) are detected in the blood and organs of lethally irradiated animals, might indicate their participation in the pathogenesis of the intestinal syndrome.

  7. Some biochemical characteristics of a toxic substance isolated from organs of lethally irradiated animals in the course of the intestinal syndrome

    International Nuclear Information System (INIS)

    Meter, J.D.; Sirota, N.S.

    1976-01-01

    A toxic substance isolated from organs of lethally irradiated (1300 rads) animals in the period when intestinal syndrome has developed is classified according to the parameters under study (namely, the molecular weight, UV-absorption curve, extinction coefficient, specific monosaccharides, the presence and percentage of KDA, etc.) as lipopolysaccharide of Escherichia coli, the main inhabitant of the gastroenteric tract of mice. That endotoxins (sensitivity to which is increased in this period of radiation sickness) are detected in the blood and organs of lethally irradiated animals, might indicate their participation in the pathogenesis of the intestinal syndrome

  8. Analysis of gas-phase mercury sorption with coke and lignite dust

    Directory of Open Access Journals (Sweden)

    Marczak Marta

    2017-01-01

    Full Text Available In recent years the problem of mercury emission became a widely discussed topic. Its high impact is caused by its toxicity and ability to accumulate in living organisms, properties that justified the United States Environmental Protection Agency (US EPA to classify mercury as hazardous pollutant. The problem of mercury emission is crucial for countries like Poland, where the most of the emission is caused by coaldepended energy sector. Current technology of mercury removal utilizes adsorption of mercury on the surface of activated carbon. Due to high price of activated carbon, this technological approach seems to be uneconomical and calls for cheaper alternative. One possible solution can be usage of other sorptive materials obtained from thermal processes like coke production. Example of such material is coke dust obtained from dry quenching of coke. The aim of this work was to analyse the sorption potential of lignite and coke dust and determine parameters influencing mercury behaviour during combustion.

  9. In situ exposures using caged organisms: a multi-compartment approach to detect aquatic toxicity and bioaccumulation

    International Nuclear Information System (INIS)

    Burton, G. Allen; Greenberg, Marc S.; Rowland, Carolyn D.; Irvine, Cameron A.; Lavoie, Daniel R.; Brooker, John A.; Moore, Laurie; Raymer, Delia F.N.; McWilliam, Ruth A.

    2005-01-01

    An in situ toxicity and bioaccumulation assessment approach is described to assess stressor exposure and effects in surface waters (low and high flow), the sediment-water interface, surficial sediments and pore waters (including groundwater upwellings). This approach can be used for exposing species, representing major functional and taxonomic groups. Pimephales promelas, Daphnia magna, Ceriodaphnia dubia, Hyalella azteca, Hyalella sp., Chironomus tentans, Lumbriculus variegatus, Hydra attenuatta, Hexagenia sp. and Baetis tibialis were successfully used to measure effects on survival, growth, feeding, and/or uptake. Stressors identified included chemical toxicants, suspended solids, photo-induced toxicity, indigenous predators, and flow. Responses varied between laboratory and in situ exposures in many cases and were attributed to differing exposure dynamics and sample-processing artifacts. These in situ exposure approaches provide unique assessment information that is complementary to traditional laboratory-based toxicity and bioaccumulation testing and reduce the uncertainties of extrapolating from the laboratory to field responses. - In situ exposures provide unique information that is complementary to traditional lab-based toxicity results

  10. The Lunar Dust Environment

    Science.gov (United States)

    Szalay, Jamey Robert

    Planetary bodies throughout the solar system are continually bombarded by dust particles, largely originating from cometary activities and asteroidal collisions. Surfaces of bodies with thick atmospheres, such as Venus, Earth, Mars and Titan are mostly protected from incoming dust impacts as these particles ablate in their atmospheres as 'shooting stars'. However, the majority of bodies in the solar system have no appreciable atmosphere and their surfaces are directly exposed to the flux of high speed dust grains. Impacts onto solid surfaces in space generate charged and neutral gas clouds, as well as solid secondary ejecta dust particles. Gravitationally bound ejecta clouds forming dust exospheres were recognized by in situ dust instruments around the icy moons of Jupiter and Saturn, and had not yet been observed near bodies with refractory regolith surfaces before NASA's Lunar Dust and Environment Explorer (LADEE) mission. In this thesis, we first present the measurements taken by the Lunar Dust Explorer (LDEX), aboard LADEE, which discovered a permanently present, asymmetric dust cloud surrounding the Moon. The global characteristics of the lunar dust cloud are discussed as a function of a variety of variables such as altitude, solar longitude, local time, and lunar phase. These results are compared with models for lunar dust cloud generation. Second, we present an analysis of the groupings of impacts measured by LDEX, which represent detections of dense ejecta plumes above the lunar surface. These measurements are put in the context of understanding the response of the lunar surface to meteoroid bombardment and how to use other airless bodies in the solar system as detectors for their local meteoroid environment. Third, we present the first in-situ dust measurements taken over the lunar sunrise terminator. Having found no excess of small grains in this region, we discuss its implications for the putative population of electrostatically lofted dust.

  11. Will Organic Synthesis Within Icy Grains or on Dust Surfaces in the Primitive Solar Nebula Completely Erase the Effects of Photochemical Self Shielding?

    Science.gov (United States)

    Nuth, Joseph A., III; Johnson, Natasha M.

    2012-01-01

    There are at least 3 separate photochemical self-shielding models with different degrees of commonality. All of these models rely on the selective absorption of (12))C(16)O dissociative photons as the radiation source penetrates through the gas allowing the production of reactive O-17 and O-18 atoms within a specific volume. Each model also assumes that the undissociated C(16)O is stable and does not participate in the chemistry of nebular dust grains. In what follows we will argue that this last, very important assumption is simply not true despite the very high energy of the CO molecular bond.

  12. Toxic effects of chlorinated organic compounds and potassium dichromate on growth rate and photosynthesis of marine phytoplankton

    DEFF Research Database (Denmark)

    Kusk, Kresten Ole; Nyholm, Niels

    1992-01-01

    The toxic effects of potassium dichromate (K2Cr2O7), 3,4-dichloroaniline (DCA) and 2,4-dichlorophenol (DCP) on the photosynthesis of natural marine phytoplankton and five species of marine microalgae were investigated. Effect concentrations corresponding to a 50 % depression of photosynthesis (6h...

  13. QSAR modeling of toxicity of diverse organic chemicals to Daphnia magna using 2D and 3D descriptors

    International Nuclear Information System (INIS)

    Kar, Supratik; Roy, Kunal

    2010-01-01

    One of the major economic alternatives to experimental toxicity testing is the use of quantitative structure-activity relationships (QSARs) which are used in formulating regulatory decisions of environmental protection agencies. In this background, we have modeled a large diverse group of 297 chemicals for their toxicity to Daphnia magna using mechanistically interpretable descriptors. Three-dimensional (3D) (electronic and spatial) and two-dimensional (2D) (topological and information content indices) descriptors along with physicochemical parameter log K o/w (n-octanol/water partition coefficient) and structural descriptors were used as predictor variables. The QSAR models were developed by stepwise multiple linear regression (MLR), partial least squares (PLS), genetic function approximation (GFA), and genetic PLS (G/PLS). All the models were validated internally and externally. Among several models developed using different chemometric tools, the best model based on both internal and external validation characteristics was a PLS equation with 7 descriptors and three latent variables explaining 67.8% leave-one-out predicted variance and 74.1% external predicted variance. The PLS model suggests that higher lipophilicity and electrophilicity, less negative charge surface area and presence of ether linkage, hydrogen bond donor groups and acetylenic carbons are responsible for greater toxicity of chemicals. The developed model may be used for prediction of toxicity, safety and risk assessment of chemicals to achieve better ecotoxicological management and prevent adverse health consequences.

  14. QSAR modeling of toxicity of diverse organic chemicals to Daphnia magna using 2D and 3D descriptors

    Energy Technology Data Exchange (ETDEWEB)

    Kar, Supratik [Drug Theoretics and Cheminformatics Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Raja S C Mullick Road, Kolkata 700032 (India); Roy, Kunal, E-mail: kunalroy_in@yahoo.com [Drug Theoretics and Cheminformatics Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Raja S C Mullick Road, Kolkata 700032 (India)

    2010-05-15

    One of the major economic alternatives to experimental toxicity testing is the use of quantitative structure-activity relationships (QSARs) which are used in formulating regulatory decisions of environmental protection agencies. In this background, we have modeled a large diverse group of 297 chemicals for their toxicity to Daphnia magna using mechanistically interpretable descriptors. Three-dimensional (3D) (electronic and spatial) and two-dimensional (2D) (topological and information content indices) descriptors along with physicochemical parameter log K{sub o/w} (n-octanol/water partition coefficient) and structural descriptors were used as predictor variables. The QSAR models were developed by stepwise multiple linear regression (MLR), partial least squares (PLS), genetic function approximation (GFA), and genetic PLS (G/PLS). All the models were validated internally and externally. Among several models developed using different chemometric tools, the best model based on both internal and external validation characteristics was a PLS equation with 7 descriptors and three latent variables explaining 67.8% leave-one-out predicted variance and 74.1% external predicted variance. The PLS model suggests that higher lipophilicity and electrophilicity, less negative charge surface area and presence of ether linkage, hydrogen bond donor groups and acetylenic carbons are responsible for greater toxicity of chemicals. The developed model may be used for prediction of toxicity, safety and risk assessment of chemicals to achieve better ecotoxicological management and prevent adverse health consequences.

  15. Toxicity and oxidative stress of different forms of organic selenium (Se) and dietary protein in mallard (Anas platyrhynchos) ducklings

    Science.gov (United States)

    Hoffman, D.; Heinz, G.; Eisemann, J.; Pendleton, G.

    1994-01-01

    High concentrations of Se have been found in aquatic food chains associated with irrigation drainwater and toxicity to fish and wildlife. Earlier studies have compared toxicities of Se as selenite and as seleno-DL-methionine (DL) in mallards. This study compares DL, seleno-L-methionine (L), selenized yeast (Y) and selenized wheat (W). Day-old mallard ducklings received an untreated diet (controls) containing 75% wheat (22% protein) or the same diet containing 15 or 30 ppm Se in the above forms. After 2 weeks blood and liver samples were collected for biochemical assays and Se analysis. All forms of selenium caused significant increases in plasma and hepatic glutathione peroxidase activities. Se as L was the most toxic, resulting in high mortality (64%) and impaired growth (>50%) and the greatest increase in ratio of oxidized to reduced glutathione with 30 ppm in the diet. Se as Y accumulated the least in liver. In a subsequent experiment with 30% dietary protein Se as L was less toxic.

  16. CeO2 nanoparticles induce no changes in phenanthrene toxicity to the soil organisms Porcellionides pruinosus and Folsomia candida.

    Science.gov (United States)

    Tourinho, Paula S; Waalewijn-Kool, Pauline L; Zantkuijl, Irene; Jurkschat, Kerstin; Svendsen, Claus; Soares, Amadeu M V M; Loureiro, Susana; van Gestel, Cornelis A M

    2015-03-01

    Cerium oxide nanoparticles (CeO2 NPs) are used as diesel fuel additives to catalyze oxidation. Phenanthrene is a major component of diesel exhaust particles and one of the most common pollutants in the environment. This study aimed at determining the effect of CeO2 NPs on the toxicity of phenanthrene in Lufa 2.2 standard soil for the isopod Porcellionides pruinosus and the springtail Folsomia candida. Toxicity tests were performed in the presence of CeO2 concentrations of 10, 100 or 1000mg Ce/kg dry soil and compared with results in the absence of CeO2 NPs. CeO2 NPs had no adverse effects on isopod survival and growth or springtail survival and reproduction. For the isopods, LC50s for the effect of phenanthrene ranged from 110 to 143mg/kg dry soil, and EC50s from 17.6 to 31.6mg/kg dry soil. For the springtails, LC50s ranged between 61.5 and 88.3mg/kg dry soil and EC50s from 52.2 to 76.7mg/kg dry soil. From this study it may be concluded that CeO2 NPs have a low toxicity and do not affect toxicity of phenanthrene to isopods and springtails. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Influence of water temperature and waterborne cadmium toxicity on growth performance and metallothionein-cadmium distribution in different organs of Nile tilapia, Oreochromis niloticus (L.).

    Science.gov (United States)

    Abdel-Tawwab, Mohsen; Wafeek, Mohammed

    2014-10-01

    Cadmium (Cd) is believed to be one of the most abundant and ubiquitously distributed toxins in the aquatic system. This metal is released to the aquatic environment from both anthropogenic sources, such as industrial, agricultural and urban effluents as well as natural sources, such as rocks and soils. Otherwise, the temperature increase of water bodies, which has been observed due to global climatic changes, has been shown to increase Cd toxicity for several aquatic animal species including fish. In the present study, Nile tilapia, Oreochromis niloticus (L.), (26.0 ± 0.38 g) were reared at 20, 24, 28, or 32 °C and exposed to 0.0 or 0.5mg Cd/L for 8 weeks to investigate effects of water temperature, Cd toxicity and their interaction on fish performance as well as metallothionein (MT) and Cd distribution in different fish organs. It was found that fish reared in Cd-free group at 28 °C showed the optimum growth and feed intake, while Cd-exposed fish showed low growth and feed intake irrespective to water temperature. A synergetic relationship between water temperature and Cd toxicity was observed where Cd toxicity increased as water temperature increased and the worse growth was obtained in Cd-exposed fish reared at 32 °C. Additionally, the highest Cd residues in different fish organs were detected in Cd-exposed fish reared at 32 °C. Similarly, MT concentrations in different fish organs increased as water temperature increased especially in Cd-exposed fish groups. A high positive correlation between MT and Cd concentrations in fish organs was detected. The distribution of MT and Cd levels was in the order of liver>kidney>gills>muscles. The present study revealed that the optimum water temperature suitable for Nile tilapia growth is 28 °C. Additionally, Cd exposure had a deteriorate effect on the growth and health of Nile tilapia. This hazardous effect increased as water temperature increased. Further, liver and kidney were the prime sites of Cd accumulation

  18. Dust Devil Tracks

    Science.gov (United States)

    2002-01-01

    (Released 8 May 2002) The Science This image, centered near 50.0 S and 17.7 W displays dust devil tracks on the surface. Most of the lighter portions of the image likely have a thin veneer of dust settled on the surface. As a dust devil passes over the surface, it acts as a vacuum and picks up the dust, leaving the darker substrate exposed. In this image there is a general trend of many of the tracks running from east to west or west to east, indicating the general wind direction. There is often no general trend present in dust devil tracks seen in other images. The track patterns are quite ephemeral and can completely change or even disappear over the course of a few months. Dust devils are one of the mechanisms that Mars uses to constantly pump dust into the ubiquitously dusty atmosphere. This atmospheric dust is one of the main driving forces of the present Martian climate. The Story Vrrrrooooooooom. Think of a tornado, the cartoon Tasmanian devil, or any number of vacuum commercials that powerfully suck up swirls of dust and dirt. That's pretty much what it's like on the surface of Mars a lot of the time. Whirlpools of wind called

  19. Marine chemistry, fish / shell-fish surveys, benthic organisms, and marine toxic substances and pollutants data from current meter and other instruments in the Gulf of Mexico from 1993-01-26 to 1994-06-13 (NODC Accession 9500088)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine chemistry, fish / shell-fish surveys, benthic organisms, and marine toxic substances and pollutants data were collected using current meter and other...

  20. Benthic organisms and marine toxic substances and pollutants collected using sediment sampler and net casts from the GUS III and EXCELLENCE in the Gulf of Mexico from 1978-05-24 to 1979-02-26 (NODC Accession 7900304)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic organisms and marine toxic substances and pollutants were collected using sediment sampler and net casts in the Gulf of Mexico. Data were submitted by Texas...

  1. Benthic organisms and marine toxic substances and pollutants collected using net and sediment samplers from the MT MITCHELL and other platforms from 22 May 1974 to 27 May 1974 (NODC Accession 7800886)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic organisms and marine toxic substances and pollutants were collected using sediment sampler and net casts in the coastal waters of the East coast of US. Data...

  2. Benthic organism and marine toxic substances and pollutants collected using net and sediment sampler casts from NOAA Ship RESEARCHER in Gulf of Mexico from 1979-07-23 to 1980-12-13 (NODC Accession 8200103)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic organism and marine toxic substances and pollutants were collected using net, sediment sampler, and other instruments from NOAA Ship RESEARCHER and other...

  3. Benthic organisms and marine toxic substances and pollutants data collected using net casts and other instruments from the GYRE and other platforms in NW Atlantic Ocean from 11 November 1983 to 30 July 1986 (NODC Accession 8800192)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic organisms and marine toxic substances and pollutants were collected using net casts, sediment sampler, and other instruments from the GYRE and other...

  4. Chemical, benthic organisms, zooplankton, marine toxic substances, and other data from moored current meter casts and other instruments in the Gulf of Mexico during the Brine Disposal project, 1979-08-30 to 1981-09-21 (NODC Accession 8200012)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chemical, marine toxic substances, benthic organisms, zooplankton, and other data were collected using moored current meter casts and other instruments in the Gulf...

  5. Effect of soil organic matter content and pH on the toxicity of ZnO nanoparticles to Folsomia candida.

    Science.gov (United States)

    Waalewijn-Kool, Pauline L; Rupp, Svenja; Lofts, Stephen; Svendsen, Claus; van Gestel, Cornelis A M

    2014-10-01

    Organic matter (OM) and pH may influence nanoparticle fate and effects in soil. This study investigated the influence of soil organic matter content and pH on the toxicity of ZnO-NP and ZnCl2 to Folsomia candida in four natural soils, having between 2.37% and 14.7% OM and [Formula: see text] levels between 5.0 and 6.8. Porewater Zn concentrations were much lower in ZnO-NP than in ZnCl2 spiked soils, resulting in higher Freundlich sorption constants for ZnO-NP. For ZnCl2 the porewater Zn concentrations were significantly higher in less organic soils, while for ZnO-NP the highest soluble Zn level (23mgZn/l) was measured in the most organic soil, which had the lowest pH. Free Zn(2+) ion concentrations were higher for ZnCl2 than for ZnO-NP and were greatly dependent on pH (pHpw) and dissolved organic carbon content of the pore water. The 28-d EC50 values for the effect of ZnCl2 on the reproduction of F. candida increased with increasing OM content from 356 to 1592mgZn/kg d.w. For ZnO-NP no correlation between EC50 values and OM content was found and EC50 values ranged from 1695 in the most organic soil to 4446mgZn/kg d.w. in the higher pH soil. When based on porewater and free Zn(2+) concentrations, EC50 values were higher for ZnCl2 than for ZnO-NP, and consistently decreased with increasing pHpw. This study shows that ZnO-NP toxicity is dependent on soil properties, but is mainly driven by soil pH. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. The Lunar Environment: Determining the Health Effects of Exposure to Moon Dusts

    Science.gov (United States)

    Khan-Mayberry, Noreen

    2007-01-01

    The moon's surface is covered with a thin layer of fine, charged, reactive dust capable of layer of fine, charged, reactive dust capable of capable of entering habitats and vehicle compartments, where it can result in crewmember health problems. NASA formed the Lunar Airborne Dust Toxicity Advisory Group (LADTAG) to study the effects of exposure to Lunar Dust on human health. To date, no scientifically defensible toxicological studies have been performed on lunar dusts, specifically the determination of exposure limits and their affect on human health. The multi-center LADTAG (Lunar Airborne Dust Toxicology center LADTAG (Lunar Airborne Dust Toxicology Advisory Group) was formed in response to the Office of the Chief Health and Medical Office s (OCHMO) request to develop recommendations for defining risk (OCHMO) request to develop recommendations for defining risk defining risk criteria for human lunar dust exposure.

  7. Toxicity Assessment of Synthetic Pyrethroids (Lambda Cyhalothrin) on the Liver and Kidney Organs of Male Wistar Rats

    OpenAIRE

    O. O. Fadina; F. I. Oshoke; O. O. Fayinminnu

    2017-01-01

    Aims: Humans and animals are occasionally and unintentionally exposed to lethal and sub lethal doses of pesticides stemming from its various uses to control pests both in agriculture, homes, gardens and public health. The use of pyrethroid products has grown and continues to grow due to the suspension of some organophosphorus and organochloride products. This current study evaluated the toxic effects of lambda-cyhalothrin (LCT) on hematological and histopathological changes in the liver and k...

  8. The toxicity of silver to soil organisms exposed to silver nanoparticles and silver nitrate in biosolids-amended field soil.

    Science.gov (United States)

    Jesmer, Alexander H; Velicogna, Jessica R; Schwertfeger, Dina M; Scroggins, Richard P; Princz, Juliska I

    2017-10-01

    The use of engineered silver nanoparticles (AgNPs) is widespread, with expected release to the terrestrial environment through the application of biosolids onto agricultural lands. The toxicity of AgNPs and silver nitrate (AgNO 3 ; as ionic Ag + ) to plant (Elymus lanceolatus and Trifolium pratense) and soil invertebrate (Eisenia andrei and Folsomia candida) species was assessed using Ag-amended biosolids applied to a natural sandy loam soil. Bioavailable Ag + in soil samples was estimated using an ion-exchange technique applied to KNO 3 soil extracts, whereas exposure to dispersible AgNPs was verified by single-particle inductively coupled plasma-mass spectrometry and transmission electron microscopy-energy dispersive X-ray spectroscopy analysis. Greater toxicity to plant growth and earthworm reproduction was observed in AgNP exposures relative to those of AgNO 3 , whereas no difference in toxicity was observed for F. candida reproduction. Transformation products in the AgNP-biosolids exposures resulted in larger pools of extractable Ag + than those from AgNO 3 -biosolids exposures, at similar total Ag soil concentrations. The results of the present study reveal intrinsic differences in the behavior and bioavailability of the 2 different forms of Ag within the biosolids-soils pathway. The present study demonstrates how analytical methods that target biologically relevant fractions can be used to advance the understanding of AgNP behavior and toxicity in terrestrial environments. Environ Toxicol Chem 2017;36:2756-2765. © 2017 Crown in the Right of Canada. Published Wiley Periodicals Inc., on behalf of SETAC. © 2017 Crown in the Right of Canada. Published Wiley Periodicals Inc., on behalf of SETAC.

  9. Whither Cometary Dust?

    Science.gov (United States)

    Lisse, Carey M.

    2010-10-01

    In this paper I will discuss recent findings that have important implications for our understanding of the formation and evolution of primitive solar system dust, including: - Nesvorny et al. (2010), following up on their dynamical analyses of the zodiacal dust bands as sourced by the breakup of the Karin (5Mya) and Veritas (8Mya) asteroid families, argue that over 90% of the interplanetary dust cloud at 1 AU comes from JFC comets with near-circularized, low inclination orbits. This implies that the noted IPD collections of anhydrous and hydrous dust particles are likely to be from Oort cloud and JFC comets, respectively, not from asteroids and comets as thought in the past. Hydrous dust particles from comets like 85P/Wild2 and 9P/Tempel 1 would be consistent with results from the STARDUST and Deep Impact experiments. - Estimates of the dust particle size distributions (PSDs) in the comae of 85P/Wild2 (Green et al. 2004, 2007) and 73P/SW-3 (Sitko et al. 2010, Vaubaillon & Reach 2010) and in the trails of comets (Reach et al. 2007) have broken power law structure, with a plateau enhancement of particles of 1 mm - 1 cm in size. This size is also the size of most chondritic inclusions, and the predicted size range of the "aggregational barrier", where collisions between dust particles become destructive. - Studies of the albedo and polarization properties of cometary dust (Kolokolova et al. 2007) suggest there are 2 major groupings, one with low scattering capability and one with high. While these families could possibly have been explained by systematics in the PSDs of the emitted dust, independent work by Lisse et al. (2008) on the mineralogy of a number of highly dusty comets has shown evidence for one family of comets with highly crystalline dust and another with highly amorphous dust.

  10. Machine learning for toxicity characterization of organic chemical emissions using USEtox database: Learning the structure of the input space.

    Science.gov (United States)

    Marvuglia, Antonino; Kanevski, Mikhail; Benetto, Enrico

    2015-10-01

    Toxicity characterization of chemical emissions in Life Cycle Assessment (LCA) is a complex task which usually proceeds via multimedia (fate, exposure and effect) models attached to models of dose-response relationships to assess the effects on target. Different models and approaches do exist, but all require a vast amount of data on the properties of the chemical compounds being assessed, which are hard to collect or hardly publicly available (especially for thousands of less common or newly developed chemicals), therefore hampering in practice the assessment in LCA. An example is USEtox, a consensual model for the characterization of human toxicity and freshwater ecotoxicity. This paper places itself in a line of research aiming at providing a methodology to reduce the number of input parameters necessary to run multimedia fate models, focusing in particular to the application of the USEtox toxicity model. By focusing on USEtox, in this paper two main goals are pursued: 1) performing an extensive exploratory analysis (using dimensionality reduction techniques) of the input space constituted by the substance-specific properties at the aim of detecting particular patterns in the data manifold and estimating the dimension of the subspace in which the data manifold actually lies; and 2) exploring the application of a set of linear models, based on partial least squares (PLS) regression, as well as a nonlinear model (general regression neural network--GRNN) in the seek for an automatic selection strategy of the most informative variables according to the modelled output (USEtox factor). After extensive analysis, the intrinsic dimension of the input manifold has been identified between three and four. The variables selected as most informative may vary according to the output modelled and the model used, but for the toxicity factors modelled in this paper the input variables selected as most informative are coherent with prior expectations based on scientific knowledge

  11. Communication plan for windblown dust.

    Science.gov (United States)

    2015-05-01

    Windblown dust events occur in Arizona, and blowing dust has been considered a contributing factor to serious crashes on the : segment of Interstate 10 (I10) between Phoenix and Tucson, as well as on other Arizona roadways. Arizonas dust events...

  12. Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats 22). Effects of 2- and 4-week administration of theobromine on the testis.

    Science.gov (United States)

    Funabashi, H; Fujioka, M; Kohchi, M; Tateishi, Y; Matsuoka, N

    2000-10-01

    The effects of theobromine, a xanthine derivative, on the testis were compared between rats dosed for 2 and 4 weeks to determine whether a 2-week dosing period is long enough to detect toxicity. Theobromine was administered orally to male Sprague-Dawley rats at dose levels of 250 and 500 mg/kg for 2 weeks starting at the age of 6 or 8 weeks, and for 4 weeks from the age of 6 weeks. Histopathological examination of reproductive organs revealed toxic findings in the testis at 500 mg/kg after 2 weeks of dosing at both ages, and at 250 and 500 mg/kg after 4 weeks of dosing. The primary findings were degeneration/necrosis and desquamation of spermatids and spermatocytes, vacuolization of seminiferous tubules, and multinucleated giant cell formation. These findings were present mainly in stages I-VI and XII-XIV. From these results, it is concluded that the toxic effects of theobromine on the testis can be detected by repeated dosing for 2 weeks as well as for 4 weeks.

  13. Effects of exposure to grain dust in Polish farmers: work-related symptoms and immunologic response to microbial antigens associated with dust.

    Science.gov (United States)

    Skórska, C; Mackiewicz, B; Dutkiewicz, J; Krysińska-Traczyk, E; Milanowski, J; Feltovich, H; Lange, J; Thorne, P

    1998-01-01

    Medical examinations were performed in a group of 76 Polish farmers heavily exposed to grain dust during harvesting and threshing, and in a group of 63 healthy urban dwellers not exposed to organic dusts (controls). The examinations included: interview concerning the occurrence of respiratory disorders and work-related symptoms, physical examination, lung function tests, and allergological tests comprising skin prick test with 4 microbial antigens associated with grain dust and agar-gel precipitation test with 12 microbial antigens. As many as 34 farmers (44.7%) reported the occurrence of work-related symptoms during harvesting and threshing. The most common was dry cough reported by 20 individuals (26.3%). Dyspnoea was reported by 15 farmers (19.7%), tiredness by 12 (15.7%), chest tightness by 8 (10.5%), plugging of nose and hoarseness by 5 each (6. 5%). No control subjects reported these work-related symptoms. The mean spirometric values in the examined group of farmers were within the normal range, but a significant post-shift decrease of these values was observed after work with grain. The farmers showed a frequency of the positive early skin reactions to environmental allergens in the range of 10.8 - 45.5%, and a frequency of positive precipitin reactions in range of 3.9 - 40.8%. The control group responded to the majority of allergens with a significantly lower frequency of positive results compared to the farmers. The obtained results showed a high response of grain farmers to inhalant microbial allergens and indicate a potential risk of occupational respiratory diseases (such as allergic alveolitis, asthma, Organic Dust Toxic Syndrome) among this population

  14. Dust in planetary nebulae

    International Nuclear Information System (INIS)

    Mathis, J.S.

    1978-01-01

    The author's review concentrates on theoretical aspects of dust in planetary nebulae (PN). He considers the questions: how much dust is there is PN; what is its composition; what effects does it have on the ionization structure, on the dynamics of the nebula. (Auth.)

  15. Combustible dust tests

    Science.gov (United States)

    The sugar dust explosion in Georgia on February 7, 2008 killed 14 workers and injured many others (OSHA, 2009). As a consequence of this explosion, OSHA revised its Combustible Dust National Emphasis (NEP) program. The NEP targets 64 industries with more than 1,000 inspections and has found more tha...

  16. Release of copper from sintered tungsten-bronze shot under different pH conditions and its potential toxicity to aquatic organisms

    International Nuclear Information System (INIS)

    Thomas, Vernon G.; Santore, Robert C.; McGill, Ian

    2007-01-01

    Sintered tungsten-bronze is a new substitute for lead shot, and is about to be deposited in and around the wetlands of North America. This material contains copper in the alloyed form of bronze. This in vitro study was performed according to U.S. Fish and Wildlife Service criteria to determine the dissolution rate of copper from the shot, and to assess the toxic risk that it may present to aquatic organisms. The dissolution of copper from tungsten-bronze shot, pure copper shot, and glass beads was measured in a buffered, moderately hard, synthetic water of pH 5.5, 6.6, and 7.8 over a 28-day period. The dissolution of copper from both the control copper shot and the tungsten-bronze shot was affected significantly by the pH of the water and the duration of dissolution (all p values < 0.000). The rate of copper release from tungsten bronze shot was 30 to 50 times lower than that from the copper shot, depending on pH (p < 0.0000). The observed expected environmental concentration of copper released from tungsten-bronze shot after 28 days was 0.02 μg/L at pH 7.8, and 0.4 μg/L at pH 5.6, using a loading and exposure scenario specific in a U.S. Fish and Wildlife Service protocol. Ratio Quotient values derived from the highest EEC observed in this study (0.4 μg/L), and the copper toxic effect levels for all aquatic species listed in the U.S. Environmental Protection Agency ambient water quality criteria database, were all far less than the 0.1 criterion value. Given the conditions stipulated by the U.S. Fish and Wildlife Service and the U.S. Environmental Protection Agency, heavy loading from discharged tungsten-bronze shot would not pose a toxic risk to potable water, or to soil. Consequently, it would appear that no toxic risks to aquatic organisms will attend the use of tungsten-bronze shot of the approved composition. Given the likelihood that sintered tungsten-bronze of the same formula will be used for fishing weights, bullets, and wheel balance weights, it is

  17. Response of the Eastern Mediterranean microbial ecosystem to dust and dust affected by acid processing in the atmosphere

    Directory of Open Access Journals (Sweden)

    Michael David Krom

    2016-08-01

    Full Text Available Acid processes in the atmosphere, particularly those caused by anthropogenic acid gases, increase the amount of bioavailable P in dust and hence are predicted to increase microbial biomass and primary productivity when supplied to oceanic surface waters. This is likely to be particularly important in the Eastern Mediterranean Sea (EMS, which is P limited during the winter bloom and N&P co-limited for phytoplankton in summer. However, it is not clear how the acid processes acting on Saharan dust will affect the microbial biomass and primary productivity in the EMS. Here, we carried out bioassay manipulations on EMS surface water on which Saharan dust was added as dust (Z, acid treated dust (ZA, dust plus excess N (ZN and acid treated dust with excess N (ZNA during springtime (May 2012 and measured bacterioplankton biomass, metabolic and other relevant chemical and biological parameters. We show that acid treatment of Saharan dust increased the amount of bioavailable P supplied by a factor of ~40 compared to non-acidified dust (18.4 nmoles P mg-1 dust vs. 0.45 nmoles P mg-1 dust, respectively. The increase in chlorophyll, primary and bacterial productivity for treatments Z and ZA were controlled by the amount of N added with the dust while those for treatments ZN and ZNA (in which excessive N was added were controlled by the amount of P added. These results confirm that the surface waters were N&P co-limited for phytoplankton during springtime. However, total chlorophyll and primary productivity in the acid treated dust additions (ZA and ZNA were less than predicted from that calculated from the amount of the potentially limiting nutrient added. This biological inhibition was interpreted as being due to labile trace metals being added with the acidified dust. A probable cause for this biological inhibition was the addition of dissolved Al, which forms potentially toxic Al nanoparticles when added to seawater. Thus, the effect of anthropogenic acid

  18. Respirable dust measured downwind during rock dust application.

    Science.gov (United States)

    Harris, M L; Organiscak, J; Klima, S; Perera, I E

    2017-05-01

    The Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health (NIOSH) conducted underground evaluations in an attempt to quantify respirable rock dust generation when using untreated rock dust and rock dust treated with an anticaking additive. Using personal dust monitors, these evaluations measured respirable rock dust levels arising from a flinger-type application of rock dust on rib and roof surfaces. Rock dust with a majority of the respirable component removed was also applied in NIOSH's Bruceton Experimental Mine using a bantam duster. The respirable dust measurements obtained downwind from both of these tests are presented and discussed. This testing did not measure miners' exposure to respirable coal mine dust under acceptable mining practices, but indicates the need for effective continuous administrative controls to be exercised when rock dusting to minimize the measured amount of rock dust in the sampling device.

  19. Lunar Dust Mitigation Screens

    Science.gov (United States)

    Knutson, Shawn; Holloway, Nancy

    With plans for the United States to return to the moon, and establish a sustainable human presence on the lunar surface many issues must be successfully overcome. Lunar dust is one of a number of issues with the potential to create a myriad of problems if not adequately addressed. Samples of dust brought back from Apollo missions show it to be soft, yet sharp and abrasive. The dust consists of a variety of morphologies including spherical, angular blocks, shards, and a number of irregular shapes. One of the main issues with lunar dust is its attraction to stick to anything it comes in contact with (i.e. astronauts, equipment, habitats, etc.). Ionized radiation from the sun strikes the moon's surface and creates an electrostatic charge on the dust. Further, the dust harbors van der Waals forces making it especially difficult to separate once it sticks to a surface. During the Apollo missions, it was discovered that trying to brush the lunar dust from spacesuits was not effective, and rubbing it caused degradation of the suit material. Further, when entering the lunar module after moonwalks, the astronauts noted that the dust was so prolific inside the cabin that they inhaled and ingested it, causing at least one of them, Harrison "Jack" Schmidt, to report irritation of the throat and lungs. It is speculated that the dust could also harm an astronaut's nervous and cardiovascular systems, especially during an extended stay. In addition to health issues, the dust can also cause problems by scouring reflective coatings off of thermal blankets, and roughening surfaces of windows and optics. Further, panels on solar cells and photovoltaics can also be compromised due to dust sticking on the surfaces. Lunar dust has the capacity to penetrate seals, interfere with connectors, as well as mechanisms on digging machines, all of which can lead to problems and failure. To address lunar dust issues, development of electrostatic screens to mitigate dust on sur-faces is currently

  20. Quantitative Trait Loci and Inter-Organ Partitioning for Essential Metal and Toxic Analogue Accumulation in Barley.

    Directory of Open Access Journals (Sweden)

    Stefan Reuscher

    Full Text Available The concentrations of both essential nutrients and chemically similar toxic analogues accumulated in cereal grains have a major impact on the nutritional quality and safety of crops. Naturally occurring genetic diversity can be exploited for the breeding of improved varieties through introgression lines (ILs. In this study, multi-element analysis was conducted on vegetative leaves, senesced flag leaves and mature grains of a set of 54 ILs of the wild ancestral Hordeum vulgare ssp. spontaneum in the cultivated variety Hordeum vulgare ssp. vulgare cv. Scarlett. Plants were cultivated on an anthropogenically heavy metal-contaminated soil collected in an agricultural field, thus allowing simultaneous localization of quantitative trait loci (QTL for the accumulation of both essential nutrients and toxic trace elements in barley as a model cereal crop. For accumulation of the micronutrients Fe and Zn and the interfering toxin Cd, we identified 25, 16 and 5 QTL, respectively. By examining the gene content of the introgressions, we associated QTL with candidate genes based on homology to known metal homeostasis genes of Arabidopsis and rice. Global comparative analyses suggested the preferential remobilization of Cu and Fe, over Cd, from the flag leaf to developing grains. Our data identifies grain micronutrient filling as a regulated and nutrient-specific process, which operates differently from vegetative micronutrient homoeostasis. In summary, this study provides novel QTL for micronutrient accumulation in the presence of toxic analogues and supports a higher degree of metal specificity of trace element partitioning during grain filling in barley than previously reported for other cereals.

  1. Inorganic and organic mercury chloride toxicity to Coturnix: Sensitivity related to age and quantal assessment of physiologic responses

    Science.gov (United States)

    Hill, E.F.

    1982-01-01

    The toxicities of mercuric chloride (HgCl(,2)) and methylmercuric chloride (CH(,3)HgCl) were compared for coturnix (Coturnix coturnix japonica) from hatching to adulthood. Comparisons were based on: (1) Median lethal dosages (LD50) derived by administering single peroral and single intramuscular dosages of mercury, (2) median lethal concentrations (LC50) derived by feeding mercury for 5 days, (3) median toxic concentrations (TC50) derived by feeding mercury 9 weeks and measuring plasma enzyme activity, plasma electrolytes, and other blood constituents, and (4) transient changes of various blood chemistries following a single peroral dose of mercury. Acute peroral and intramuscular LD50s for HgCl(,2) and CH(,3)HgCl increased by two- to threefold for coturnix chicks from hatching to 4 weeks of age. Concomitantly, the LC50s also increased, but the important difference between test procedures was that with both single dose routes of exposure the toxicity ratios, i.e., HgCl(,2)/CH(,3)HgCl, at each age were about 2 to 2.5 compared to about 100 for the LC50s. For example, at 2 weeks of age the peroral LD50s for HgCl(,2) and CH(,3)HgCl were 42 and 18 mg/kg; the dietary LC50s were 5086 and 47 ppm for HgCl(,2) and CH(,3)HgCl. The 9 week feeding trial was not associated with gross effects from either HgCl(,2) at 0.5 to 32 ppm or CH(,3)HgCl at 0.125 to 8 ppm. However, subtle responses were detected for the plasma enzymes aspartate aminotransferase, lactate dehydrogenase, and ornithine carbamoyl transferase and could be quantified by probit analysis. This quantal procedure was based on establishment of a normal value for each enzyme and classing outliers as respondents. A 'hazard index' based on the TC50 for an enzyme divided by the LD50 or LC50 was introduced. The single oral dosages of HgCl(,2) and CH(,3)HgCl showed that ratios of alanine aminotransferase, lactate dehydrogenase, and orinthine carbamoyl transferase for the liver and kidneys of adult coturnix were opposite from

  2. Toxicity of seven priority hazardous and noxious substances (HNSs) to marine organisms: Current status, knowledge gaps and recommendations for future research

    International Nuclear Information System (INIS)

    Rocha, A. Cristina S.; Reis-Henriques, Maria Armanda; Galhano, Victor; Ferreira, Marta; Guimarães, Laura

    2016-01-01

    Shipping industry and seaborne trade have rapidly increased over the last fifty years, mainly due to the continuous increasing demand for chemicals and fuels. Consequently, despite current regulations, the occurrence of accidental spills poses an important risk. Hazardous and noxious substances (HNSs) have been raising major concern among environmental managers and scientific community for their heterogeneity, hazardous potential towards aquatic organisms and associated social-economic impacts. A literature review on ecotoxicological hazards to aquatic organisms was conducted for seven HNSs: acrylonitrile, n-butyl acrylate, cyclohexylbenzene, hexane, isononanol, trichloroethylene and xylene. Information on the mechanisms of action of the selected HNS was also reviewed. The main purpose was to identify: i) knowledge gaps in need of being addressed in future research; and ii) a set of possible biomarkers suitable for ecotoxicological assessment and monitoring in both estuarine and marine systems. Main gaps found concern the scarcity of information available on ecotoxicological effects of HNS towards marine species and their poorly understood mode of action in wildlife. Differences were found between the sensitivity of freshwater and seawater organisms, so endpoints produced in the former may not be straightforwardly employed in evaluations for the marine environment. The relationship between sub-individual effects and higher level detrimental alterations (e.g. behavioural, morphological, reproductive effects and mortality) are not fully understood. In this context, a set of biomarkers associated to neurotoxicity, detoxification and anti-oxidant defences is suggested as potential indicators of toxic exposure/effects of HNS in marine organisms. Overall, to support the development of contingency plans and the establishment of environmental safety thresholds, it will be necessary to undertake targeted research on HNS ecotoxicity in the marine environment. Research should

  3. Toxicity of seven priority hazardous and noxious substances (HNSs) to marine organisms: Current status, knowledge gaps and recommendations for future research

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, A. Cristina S., E-mail: cristinasrocha@gmail.com; Reis-Henriques, Maria Armanda; Galhano, Victor; Ferreira, Marta, E-mail: marta.ferreira@usp.ac.fj; Guimarães, Laura

    2016-01-15

    Shipping industry and seaborne trade have rapidly increased over the last fifty years, mainly due to the continuous increasing demand for chemicals and fuels. Consequently, despite current regulations, the occurrence of accidental spills poses an important risk. Hazardous and noxious substances (HNSs) have been raising major concern among environmental managers and scientific community for their heterogeneity, hazardous potential towards aquatic organisms and associated social-economic impacts. A literature review on ecotoxicological hazards to aquatic organisms was conducted for seven HNSs: acrylonitrile, n-butyl acrylate, cyclohexylbenzene, hexane, isononanol, trichloroethylene and xylene. Information on the mechanisms of action of the selected HNS was also reviewed. The main purpose was to identify: i) knowledge gaps in need of being addressed in future research; and ii) a set of possible biomarkers suitable for ecotoxicological assessment and monitoring in both estuarine and marine systems. Main gaps found concern the scarcity of information available on ecotoxicological effects of HNS towards marine species and their poorly understood mode of action in wildlife. Differences were found between the sensitivity of freshwater and seawater organisms, so endpoints produced in the former may not be straightforwardly employed in evaluations for the marine environment. The relationship between sub-individual effects and higher level detrimental alterations (e.g. behavioural, morphological, reproductive effects and mortality) are not fully understood. In this context, a set of biomarkers associated to neurotoxicity, detoxification and anti-oxidant defences is suggested as potential indicators of toxic exposure/effects of HNS in marine organisms. Overall, to support the development of contingency plans and the establishment of environmental safety thresholds, it will be necessary to undertake targeted research on HNS ecotoxicity in the marine environment. Research should

  4. Accumulation of toxic metals and organic micro-pollutants in sediments from tropical urban rivers, Kinshasa, Democratic Republic of the Congo.

    Science.gov (United States)

    Kilunga, Pitchouna I; Sivalingam, Periyasamy; Laffite, Amandine; Grandjean, Dominique; Mulaji, Crispin K; de Alencastro, Luiz Felippe; Mpiana, Pius T; Poté, John

    2017-07-01

    The increasing contamination of fresh water resource by toxic metals and Persistence Organic Pollutants (POPs) is a major environmental concern globally. In the present investigation, surface sediments collected from three main rivers named, Makelele, Kalamu and Nsanga, draining through the city of Kinshasa, Democratic Republic of the Congo, were characterized for grain size, organic matter, toxic metals, POPs (including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs)), and polycyclic aromatic hydrocarbons (PAHs). Furthermore, enrichment factor (EF) and geoaccumulation index (Igeo) were performed to determine metal source and pollution status. The results highlighted high concentration of toxic metals in all sediment samples, reaching the values (mg kg -1 ) of 325 (Cu), 549 (Zn), 165 (Pb) and 1.5 (Cd). High values of PCBs and OCPs were detected in sediment samples, e.g. in Makelele river, PCB values ranged from 0.9 to 10.9 with total PCBs (∑7 PCBs × 4.3): 169.3 μg kg -1 ; OCPs from 21.6 to 146.8 with ∑OCPs: 270.6 μg kg -1 . The PBDEs concentrations were higher in investigated rivers comparatively with values detected in many rivers from Sub-Saharan Africa. The ΣPAHs value ranged from 22.6 to 1011.9 μg kg -1 . River contamination may be explained by local intense domestic activities, urban and agricultural runoff, industrial and hospital wastewaters discharge into the rivers without prior treatment. This research provides not only a first baseline information on the extent of contamination in this tropical ecosystem but also represents useful tools incorporated to evaluate sediment quality in the river receiving systems which can be applied to similar aquatic environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Construction and applications of DNA probes for detection of polychlorinated biphenyl-degrading genotypes in toxic organic-contaminated soil environments

    International Nuclear Information System (INIS)

    Walia, S.; Khan, A.; Rosenthal, N.

    1990-01-01

    Several DNA probes for polychlorinated biphenyl (PCB)-degrading genotypes were constructed from PCB-degrading bacteria. These laboratory-engineered DNA probes were used for the detection, enumeration, and isolation of specific bacteria degrading PCBs. Dot blot analysis of purified DNA from toxic organic chemical-contaminated soil bacterial communities showed positive DNA-DNA hybridization with a 32P-labeled DNA probe (pAW6194, cbpABCD). Less than 1% of bacterial colonies isolated from garden topsoil and greater than 80% of bacteria isolated from PCB-contaminated soils showed DNA homologies with 32P-labeled DNA probes. Some of the PCB-degrading bacterial isolates detected by the DNA probe method did not show biphenyl clearance. The DNA probe method was found to detect additional organisms with greater genetic potential to degrade PCBs than the biphenyl clearance method did. Results from this study demonstrate the usefulness of DNA probes in detecting specific PCB-degrading bacteria, abundance of PCB-degrading genotypes, and genotypic diversity among PCB-degrading bacteria in toxic chemical-polluted soil environments. We suggest that the DNA probe should be used with caution for accurate assessment of PCB-degradative capacity within soils and further recommend that a combination of DNA probe and biodegradation assay be used to determine the abundance of PCB-degrading bacteria in the soil bacterial community

  6. Toxic metals (Ni2+, Pb2+, Hg2+) binding affinity of dissolved organic matter (DOM) derived from different ages municipal landfill leachate

    Science.gov (United States)

    Rikta, S. Y.; Tareq, Shafi M.; Uddin, M. Khabir

    2018-03-01

    Solid waste production is rapidly increasing in Bangladesh and landfill leachate is the consequence of the decomposition of this waste. These leachates contain heavy metals and significant amount of dissolved organic matter (DOM). DOM is known to have considerable role in heavy metals speciation. Hence, it is important to characterize DOM/leachate and evaluate toxic metals binding affinity of DOM. The objectives of this study were to characterize the DOM in landfill leachate through physico-chemical and optical analyses and to investigate the toxic metals (Ni2+, Pb2+ and Hg2+) binding affinity of three different ages (fresh sample L-1, young sample L-2 and mature sample L-3) DOM samples. Results suggested that leachate is a potential pollutant which contained very high organic pollutant load. Conditional stability constant (Log K) and percentages of fluorophores that correspond to metal binding (% f) values indicated that young DOM sample (L-2) had the highest binding affinity to all the three metals ions. In general, DOM samples showed the following order affinity to the metal ions; Ni2+ binding affinity: L-2 > L-3 > L-1, Pb2+ binding affinity: L-2 > L-3 > L-1 and Hg2+ binding affinity: L-2 > L-1 > L-3.

  7. Applications of high-speed dust injection to magnetic fusion

    International Nuclear Information System (INIS)

    Wang, Zhehui; Li, Yangfang

    2012-01-01

    It is now an established fact that a significant amount of dust is produced in magnetic fusion devices due to plasma-wall interactions. Dust inventory must be controlled, in particular for the next-generation steady-state fusion machines like ITER, as it can pose significant safety hazards and degrade performance. Safety concerns are due to tritium retention, dust radioactivity, toxicity, and flammability. Performance concerns include high-Z impurities carried by dust to the fusion core that can reduce plasma temperature and may even induce sudden termination of the plasma. We have recognized that dust transport, dust-plasma interactions in magnetic fusion devices can be effectively studied experimentally by injection of dust with known properties into fusion plasmas. Other applications of injected dust include diagnosis of fusion plasmas and edge localized mode (ELM)'s pacing. In diagnostic applications, dust can be regarded as a source of transient neutrals before complete ionization. ELM's pacing is a promising scheme to prevent disruptions and type I ELM's that can cause catastrophic damage to fusion machines. Different implementation schemes are available depending on applications of dust injection. One of the simplest dust injection schemes is through gravitational acceleration of dust in vacuum. Experiments at Los Alamos and Princeton will be described, both of which use piezoelectric shakers to deliver dust to plasma. In Princeton experiments, spherical particles (40 micron) have been dropped in a systematic and reproducible manner using a computer-controlled piezoelectric bending actuator operating at an acoustic (0,2) resonance. The circular actuator was constructed with a 2.5 mm diameter central hole. At resonance (∼ 2 kHz) an applied sinusoidal voltage has been used to control the flux of particles exiting the hole. A simple screw throttle located ∼1mm above the hole has been used to set the magnitude of the flux achieved for a given voltage

  8. Quantifying Anthropogenic Dust Emissions

    Science.gov (United States)

    Webb, Nicholas P.; Pierre, Caroline

    2018-02-01

    Anthropogenic land use and land cover change, including local environmental disturbances, moderate rates of wind-driven soil erosion and dust emission. These human-dust cycle interactions impact ecosystems and agricultural production, air quality, human health, biogeochemical cycles, and climate. While the impacts of land use activities and land management on aeolian processes can be profound, the interactions are often complex and assessments of anthropogenic dust loads at all scales remain highly uncertain. Here, we critically review the drivers of anthropogenic dust emission and current evaluation approaches. We then identify and describe opportunities to: (1) develop new conceptual frameworks and interdisciplinary approaches that draw on ecological state-and-transition models to improve the accuracy and relevance of assessments of anthropogenic dust emissions; (2) improve model fidelity and capacity for change detection to quantify anthropogenic impacts on aeolian processes; and (3) enhance field research and monitoring networks to support dust model applications to evaluate the impacts of disturbance processes on local to global-scale wind erosion and dust emissions.

  9. Spirit Feels Dust Gust

    Science.gov (United States)

    2007-01-01

    On sol 1149 (March 28, 2007) of its mission, NASA's Mars Exploration Rover Spirit caught a wind gust with its navigation camera. A series of navigation camera images were strung together to create this movie. The front of the gust is observable because it was strong enough to lift up dust. From assessing the trajectory of this gust, the atmospheric science team concludes that it is possible that it passed over the rover. There was, however, no noticeable increase in power associated with this gust. In the past, dust devils and gusts have wiped the solar panels of dust, making it easier for the solar panels to absorb sunlight.

  10. Short-term variability of mineral dust, metals and carbon emission from road dust resuspension

    Science.gov (United States)

    Amato, Fulvio; Schaap, Martijn; Denier van der Gon, Hugo A. C.; Pandolfi, Marco; Alastuey, Andrés; Keuken, Menno; Querol, Xavier

    2013-08-01

    Particulate matter (PM) pollution in cities has severe impact on morbidity and mortality of their population. In these cities, road dust resuspension contributes largely to PM and airborne heavy metals concentrations. However, the short-term variation of emission through resuspension is not well described in the air quality models, hampering a reliable description of air pollution and related health effects. In this study we experimentally show that the emission strength of resuspension varies widely among road dust components/sources. Our results offer the first experimental evidence of different emission rates for mineral dust, heavy metals and carbon fractions due to traffic-induced resuspension. Also, the same component (or source) recovers differently in a road in Barcelona (Spain) and a road in Utrecht (The Netherlands). This finding has important implications on atmospheric pollution modelling, mostly for mineral dust, heavy metals and carbon species. After rain events, recoveries were generally faster in Barcelona rather than in Utrecht. The largest difference was found for the mineral dust (Al, Si, Ca). Tyre wear particles (organic carbon and zinc) recovered faster than other road dust particles in both cities. The source apportionment of road dust mass provides useful information for air quality management.

  11. Assessment of contamination for inorganic elements and phthalate esters in household dust from the metropolitan region of Sao Paulo

    International Nuclear Information System (INIS)

    Scapin, Valdirene de Oliveira

    2009-01-01

    Household dust has been identified as an important vector of exposure by inorganic and organic substances potentially toxic in children and adults. The dust composition has a strong influence of contaminants provided from internal and external environments. During the natural process of wearing or weather incidents of artifacts and materials variety, the chemical substances are released into the environment in the steam form or by leaching from final products. Once released, they can be accumulated and enriched in the dust; and by continuous exposure (inhalation, ingestion and dermal contact mechanisms), these substances are harmful to human health. In this work, a study to determine the inorganic constituents and phthalate esters concentrations in residential indoor environment dust samples, correlating them with the probable anthropogenic sources was proposed. Dust samples were collected from 69 residences in neighborhoods Pirituba, Freguesia do O, Jaragua and Perus of the Sao Paulo metropolitan region, using a domestic vacuum cleaner, between 2006 and 2008. The samples were sieved in the fractions of 850, 850-300, 300-150, 150-75, 75-63 and <63 μm. The analysis by X-ray fluorescence (WDXRF) showed the presence of Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Zr and Pb. The presence of phthalate esters (DEHP, DnBP, DEP, DEHA, DMP and BBP) was detected, by GCMS analyses. From the enrichment factor (EF), the elements P, S, Cr, Ni, Cu, Zn and Pb were classified as being significant and extremely enriched in the dust. The natural and anthropogenic contributions by statistical tools as factor analysis (AF) and cluster were identified. The elements Cr, Ni, Cu, Zn and Pb were present significantly elevated concentrations in relation to the total exposure values (ingestion, inhalation and skin contact) and to risk. (author)

  12. Ecological risk assessment of toxic organic pollutant and heavy metals in water and sediment from a landscape lake in Tianjin City, China.

    Science.gov (United States)

    Zhang, Ying; Liu, Yuanyuan; Niu, Zhiguang; Jin, Shaopei

    2017-05-01

    To estimate the ecological risk of toxic organic pollutant (formaldehyde) and heavy metals (mercury (Hg), arsenic (As), cadmium (Cd), and chromium (Cr)) in water and sediment from a landscape Lake in Tianjin City, an ecological risk assessment was performed. The risk quotient (RQ) method and the AQUATOX model were used to assess the ecological risk of formaldehyde in landscape water. Meanwhile, the RQ method and the potential ecological risk index method were used to assess the ecological risk of four heavy metals in water and sediment from the studied landscape lake, respectively. The results revealed that the maximum concentration of formaldehyde in landscape water was lower than the environmental quality standards of surface water in China. The maximum simulated concentrations of formaldehyde in phytoplankton and invertebrates were 3.15 and 22.91 μg/L, respectively, which were far less than its toxicity data values (1000 and 510 μg/L, respectively), suggesting that formaldehyde in landscape water was at a safe level for aquatic organisms. The RQ model indicated that the risks of phytoplankton and invertebrates were higher than that of fish posed by Hg and Cd in landscape water, and the risks from As and Cr were acceptable for all test organisms. Cd is the most important pollution factor among all heavy metals in sediment from studied landscape lake, and the pollution factor sequence of heavy metals was Hg > As > Cr > Cd. The values of risk index (RI) for four heavy metals in samples a and b were 43.48 and 72.66, which were much lower than the threshold value (150), suggesting that the ecological risk posed by heavy metals in sediment was negligible.

  13. Galactic dust and extinction

    International Nuclear Information System (INIS)

    Lyngaa, G.

    1979-01-01

    The ratio R between visual extinction and colour excess, is slightly larger than 3 and does not vary much throughout our part of the Galaxy. The distribution of dust in the galactic plane shows, on the large scale, a gradient with higher colour excesses towards l=50 0 than towards l=230 0 . On the smaller scale, much of the dust responsible for extinction is situated in clouds which tend to group together. The correlation between positions of interstellar dust clouds and positions of spiral tracers seems rather poor in our Galaxy. However, concentrated dark clouds as well as extended regions of dust show an inclined distribution similar to the Gould belt of bright stars. (Auth.)

  14. Occurrence of polycyclic aromatic hydrocarbons in dust emitted from circulating fluidized bed boilers.

    Science.gov (United States)

    Kozielska, B; Konieczyńiski, J

    2008-11-01

    Occurrence of polycyclic aromatic hydrocarbons (PAHs) in granulometric fractions of dust emitted from a hard coal fired circulating fluidized bed (CFB) boiler was investigated. The dust was sampled with the use of a Mark III impactor. In each fraction of dust, by using gas chromatography (GC), 16 selected PAHs and total PAHs were determined and the toxic equivalent B(a)P (TE B(a)P) was computed. The results, recalculated for the standard granulometric fractions, are presented as concentrations and content of the determined PAHs in dust. Distributions of PAHs and their profiles in the granulometric dust fractions were studied also. The PAHs in dust emitted from the CFB boiler were compared with those emitted from mechanical grate boilers; a distinctly lower content of PAHs was found in dust emitted from the former.

  15. Radioisotope dust pollution monitor

    International Nuclear Information System (INIS)

    Szepke, R.; Harasimczuk, J.; Dobrowiecki, J.

    1990-01-01

    Measuring principles and specification of two dust monitors: station-type AMIZ and portable-type PIK-10 for ambient air pollution are presented. The first one, a fully automatic instrument is destined for permanent monitoring of air pollution in preset sampling time from .25 to 24 hours. The second one was developed as a portable working model. Both instruments display their results in digital form in dust concentration units. (author)

  16. Coal dust symposium

    Energy Technology Data Exchange (ETDEWEB)

    1981-03-01

    This paper gives a report of the paper presented at the symposium held in Hanover on 9 and 10 February 1981. The topics include: the behaviour of dust and coal dust on combustion and explosion; a report on the accidents which occurred at the Laegerdorf cement works' coal crushing and drying plant; current safety requirements at coal crushing and drying plant; and coal crushing and drying. Four papers are individually abstracted. (In German)

  17. Dust devil generation

    International Nuclear Information System (INIS)

    G Onishchenko, O; A Pokhotelov, O; Horton, W; Stenflo, L

    2014-01-01

    The equations describing axi-symmetric nonlinear internal gravity waves in an unstable atmosphere are derived. A hydrodynamic model of a dust devil generation mechanism in such an atmosphere is investigated. It is shown that in an unstably stratified atmosphere the convective plumes with poloidal motion can grow exponentially. Furthermore, it is demonstrated that these convective plumes in an atmosphere with weak large scale toroidal motion are unstable with respect to three-dimensional dust devil generation. (papers)

  18. Initial Considerations of a Dust Dispenser for Injecting Tungsten Particles in Space

    Science.gov (United States)

    2014-09-26

    approved for toxic dusts and fumes  May combust at high temperature  Keep away from ignition sources  Material in powder form, capable of...creating a dust explosion with ignition source Toxicity  None  None  Inert  Not available Handling and Storage  Maintain good...on oxidation: Tungsten  Does not react with air, oxygen, and water at room temperature [6]  Strongly attacked by fluorine at room temperature [6

  19. Comparative toxicity and endocrine disruption potential of urban and rural atmospheric organic PM1 in JEG-3 human placental cells

    International Nuclear Information System (INIS)

    Drooge, Barend L. van; Marqueño, Anna; Grimalt, Joan O.; Fernández, Pilar; Porte, Cinta

    2017-01-01

    Outdoor ambient air particulate matter and air pollution are related to adverse effects on human health. The present study assesses the cytotoxicity and ability to disrupt aromatase activity of organic PM 1 extracts from rural and urban areas at equivalent air volumes from 2 to 30 m 3 , in human placental JEG-3 cells. Samples were chemically analyzed for particle bounded organic compounds with endocrine disrupting potential, i.e. PAH, O-PAH, phthalate esters, but also for organic molecular tracer compounds for the emission source identification. Rural samples collected in winter were cytotoxic at the highest concentration tested and strongly inhibited aromatase activity in JEG-3 cells. No cytotoxicity was detected in summer samples from the rural site and the urban samples, while aromatase activity was moderately inhibited in these samples. In the urban area, the street site samples, collected close to intensive traffic, showed stronger inhibition of aromatase activity than the samples simultaneously collected at a roof site, 50 m above ground level. The cytotoxicity and endocrine disruption potential of the samples were linked to combustion products, i.e. PAH and O-PAH, especially from biomass burning in the rural site in winter. - Highlights: • Organic extracts of outdoor ambient air PM1 showed aromatase activity inhibition in exposed human placental JEG-3 cells. • Cytotoxicity and strongest endocrine disruption was observed in rural winter samples, while lowest inhibition was observed in urban background site 50 m above a busy street. • Cytotoxicity and aromatase activity inhibition in the samples were linked to combustion products, i.e. PAH and O-PAH, especially from biomass burning. - Organic extracts from ambient air PM 1 related to biomass burning are more cytotoxic and have stronger endocrine disruption potential than urban PM 1 .

  20. Long-term use of biosolids as organic fertilizers in agricultural soils: potentially toxic elements occurrence and mobility.

    Science.gov (United States)

    Marguí, E; Iglesias, M; Camps, F; Sala, L; Hidalgo, M

    2016-03-01

    The presence of potentially toxic elements (PTEs) may hinder a more widespread application of biosolids in agriculture. At present, the European Directive 86/278/CEE limit the total concentrations of seven metals (Cu, Cr, Ni, Pb, Zn, Cd and Hg) in agricultural soils and in sewage sludges used as fertilizers but it has not taken into consideration the potential impacts of other emerging micropollutants that may be present in the biosolids as well as their mobility. The aim of this study was to evaluate the accumulation and mobility of 13 elements (including regulated metals and other inorganic species) in agricultural soils repeatedly amended with biosolids for 15 years. Firstly, three digestions programs using different acid mixtures were tested to evaluate the most accurate and efficient method for analysis of soil and sludge. Results demonstrated that sewage sludge application increased concentrations of Pb and Hg in soil, but values did not exceed the quality standard established by legislation. In addition, other elements (As, Co, Sb, Ag, Se and Mn) that at present are not regulated by the Spanish and European directives were identified in the sewage sludge, and significant differences were found between Ag content in soils amended with biosolids in comparison with control soils. This fact can be related to the increasing use of silver nanoparticles in consumer products due to their antibacterial properties. Results from the leaching tests show up that, in general, the mobility degree for both regulated and non-regulated elements in soils amended with biosolids was quite low (<10 %).

  1. Histopathological changes induced by acute toxicity of mercuric chloride on the air-breathing organ (branchial diverticulum) of the life-fish Heteropneustes (= Saccobranchus) fossilis (BLOCH)

    Energy Technology Data Exchange (ETDEWEB)

    Rajan, M.T. (Histochemistry and Histopathology Lab., Dept. of Zoology, Banaras Hindu Univ., Varanasi (India)); Banerjee, T.K. (Histochemistry and Histopathology Lab., Dept. of Zoology, Banaras Hindu Univ., Varanasi (India))

    1993-01-01

    Toxicity induced by 0.3 ppm (96 h LC[sub 50] value) mercuric chloride solution on the histomorphology of the innerlining of the air breathing organ (branchial diverticulum) of Heteropneustes fossilis has been described. The outer cell layers of the epithelial lining show cyclic necrosis leading to shedding with ultimate haemorrhage and drainage of blood into the lumen causing decrease in the number of blood islets. Simultaneously the epithelium regenerates causing hyperplasia of its cells and increased gas diffusion distance impairing normal aerial respiration. Also the number of foldings decreases and the secondary lamella like structures fuse together. This results in smoothening of the inner lining of the air sac. Later reappearance of the blood islets, secondary lamellae and foldings of the inner lining are observed along with the repair of the epithelium. Damage of the repaired inner lining follows again. (orig.)

  2. Dissolution of heavy metals from electrostatic precipitator (ESP) dust ...

    African Journals Online (AJOL)

    SIBOO

    Key words: Fungal leaching, sponge iron, electrostatic precipitator (ESP) dust, metal dissolution. INTRODUCTION ... ability of micro organisms to transform solid compounds ..... of metals from spent lithium ion secondary batteries using A.

  3. Comparative toxicity and endocrine disruption potential of urban and rural atmospheric organic PM1 in JEG-3 human placental cells.

    Science.gov (United States)

    van Drooge, Barend L; Marqueño, Anna; Grimalt, Joan O; Fernández, Pilar; Porte, Cinta

    2017-11-01

    Outdoor ambient air particulate matter and air pollution are related to adverse effects on human health. The present study assesses the cytotoxicity and ability to disrupt aromatase activity of organic PM 1 extracts from rural and urban areas at equivalent air volumes from 2 to 30 m 3 , in human placental JEG-3 cells. Samples were chemically analyzed for particle bounded organic compounds with endocrine disrupting potential, i.e. PAH, O-PAH, phthalate esters, but also for organic molecular tracer compounds for the emission source identification. Rural samples collected in winter were cytotoxic at the highest concentration tested and strongly inhibited aromatase activity in JEG-3 cells. No cytotoxicity was detected in summer samples from the rural site and the urban samples, while aromatase activity was moderately inhibited in these samples. In the urban area, the street site samples, collected close to intensive traffic, showed stronger inhibition of aromatase activity than the samples simultaneously collected at a roof site, 50 m above ground level. The cytotoxicity and endocrine disruption potential of the samples were linked to combustion products, i.e. PAH and O-PAH, especially from biomass burning in the rural site in winter. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Regularities of dust formation during stone cutting for construction works

    Directory of Open Access Journals (Sweden)

    V.G. Lebedev

    2016-09-01

    Full Text Available When cutting stone, a large amount of dust release, which is a mixture of small, mostly sharp, mineral particles. Shallow dry dust with inhalation causes the pathological changes in organs that are a consequence of infiltration of acute and solids particles. Despite the importance of this problem, the questions of dust generation during the various working processes and its fractions distribution are practically not considered. This determines the time of dust standing in the air and its negative impact on a person. Aim: The aim of this research is to study the process of dusting during stones cutting and dust distribution on fractions regularities and quantification of dust formation process in order to improve the production equipment, staff individual and collective safety equipment. Materials and Methods: Many types of cutting can be divided into two types - a “dry” cutting and cutting with fluid. During “dry” cutting a dust represents a set of micro-chips which are cut off by the abrasive grains. The size of such chips very small: from a micrometer to a few micrometers fraction. Thus, the size of chips causes the possibility of creating dust slurry with low fall velocity, and which is located in the working space in large concentrations. Results: The following characteristic dependences were obtained as a result of research: dependence of the dust fall from the size of the dust particles, size of dust particles from minute feeding and grain range wheel, the specific amount of dust from the number of grit abrasive wheel and the temperature of the dust particles from the feeding at wheel turnover. It was shown that the distribution of chips (dust by size will request of a normal distribution low. Dimensions of chips during cut are in the range of 0.4...6 μm. Thus, dust slurry is formed with time of particles fall of several hours. This creates considerable minute dust concentration - within 0.28∙10^8...1.68∙10^8 units/m3.

  5. Reducing dust and allergen exposure in bakeries

    Directory of Open Access Journals (Sweden)

    Howard J Mason

    2017-12-01

    Full Text Available Bakers have a continuing high incidence of occupational allergic asthma. In factory bakeries they are exposed not only to flour dust containing allergens, but also improvers whose ingredients enhance the strength and workability of the dough and its speed of rising. Improvers are flour-based but can contain added soya, fungal or bacterial enzymes that are also allergenic, as well as vegetable oil, calcium sulphate/silicate and organic esters. This study investigated the dustiness of the components used in factory bakeries and whether altering improver ingredients could reduce dust and allergen exposure. A standardised rotating drum test was employed on the individual components, as well as a representative improver and three practicable improver modifications by decreasing calcium sulphate, calcium silicate or increasing oil content. Levels of dust, the allergens wheat flour amylase inhibitor (WAAI and soya trypsin inhibitor (STI were measured in the generated inhalable, thoracic and respirable sized fractions. A “scooping and pouring” workplace simulation was also performed. Initial tests showed that dustiness of several wheat flours was relatively low, and even lower for soya flour, but increased in combination with some other improver components. All three improver modifications generally reduced levels of dust, STI and WAAI, but increasing oil content significantly decreased dust and STI in comparison to the standard improver and those improvers with reduced calcium silicate or sulphate. The simulation demonstrated that increased oil content reduced inhalable levels of gravimetric dust, STI and WAAI. Changing improver formulation, such as increasing oil content of flour by a small amount, may represent a simple, practical method of reducing bakery workers’ exposure to dust and allergens where improvers are used. It may be a useful adjunct to engineering control, changes to work practices and appropriate training in reducing the risk to

  6. FINDING WAYS OF RECYCLING DUST OF ARC STEEL FURNACES AT THE BELARUSIAN METALLURGIC PLANT. PART 3. EXPERIMENTS ON BRIQUETTING OF DUST OFARC STEEL FURNACES

    Directory of Open Access Journals (Sweden)

    A. I. Rozhkov

    2015-01-01

    Full Text Available The article gives an overview of the global experience of recycling dust by briquetting. The advantages and disadvantages of recycling dust with its preliminary briquetting are described. Information about experiments on briquetting of dust generated in different organizations of the Belarusian metallurgy plant with various binders is given. Economic calculations were performed on the basis of technical data obtained during the manufacture of prototypes of briquettes. The results of the calculations showedinexpediency of recycling dust briquetting method because of the low iron content in the dust, high cost of binder and a relatively small rate of ecological tax.

  7. Fractal dust grains in plasma

    International Nuclear Information System (INIS)

    Huang, F.; Peng, R. D.; Liu, Y. H.; Chen, Z. Y.; Ye, M. F.; Wang, L.

    2012-01-01

    Fractal dust grains of different shapes are observed in a radially confined magnetized radio frequency plasma. The fractal dimensions of the dust structures in two-dimensional (2D) horizontal dust layers are calculated, and their evolution in the dust growth process is investigated. It is found that as the dust grains grow the fractal dimension of the dust structure decreases. In addition, the fractal dimension of the center region is larger than that of the entire region in the 2D dust layer. In the initial growth stage, the small dust particulates at a high number density in a 2D layer tend to fill space as a normal surface with fractal dimension D = 2. The mechanism of the formation of fractal dust grains is discussed.

  8. Introducing Toxics

    OpenAIRE

    David C. Bellinger

    2013-01-01

    With this inaugural issue, Toxics begins its life as a peer-reviewed, open access journal focusing on all aspects of toxic chemicals. We are interested in publishing papers that present a wide range of perspectives on toxicants and naturally occurring toxins, including exposure, biomarkers, kinetics, biological effects, fate and transport, treatment, and remediation. Toxics differs from many other journals in the absence of a page or word limit on contributions, permitting authors to present ...

  9. Organic persistent toxic substances in soils, waters and sediments along an altitudinal gradient at Mt. Sagarmatha, Himalayas, Nepal

    International Nuclear Information System (INIS)

    Guzzella, Licia; Poma, Giulia; De Paolis, Adolfo; Roscioli, Claudio; Viviano, Gaetano

    2011-01-01

    Persistent Organic Pollutants (POPs) and Polycyclic Aromatic Hydrocarbons (PAHs) are important classes of compounds of serious environmental concern. These compounds were measured in waters, sediments and soils from several high altitude sites in the Sagarmatha National Park (Nepal) and included in the Himalayan ridge. In water samples, low-level substituted PCBs and PBDEs, along with more volatile PAHs, were the most common contaminants. In sediment and soil samples, the PCB profile was mainly composed of medium-level chlorinated congeners and significantly correlated with altitude. The PAH profile for water and soil samples showed the main contribution of pyrogenic PAHs due to emissions of solid combustion, whereas the profile for sediments indicated the main contribution of pyrogenic PAHs from gasoline emissions. The PAH levels measured in Himalayan samples must be considered as low to medium contaminated, whereas the regarded Himalayan stations can be considered undisturbed remote areas concerning PCB, PBDE and OC compounds. - Highlights: → POPs were measured in environmental samples from remote lakes in the Himalaya ridge. → It was confirmed the hypothesis of Long-Range Atmospheric Transport for lighter POPs. → PAH levels in Himalayan samples must be considered as low to medium contaminated. → The stations can be considered undisturbed remote areas concerning PCB, PBDE and OCC. - Organic PTSs in environmental matrices in remote regions of the Himalayan ridge.

  10. Sahara Dust Cloud

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Dust Particles Click on the image for Quicktime movie from 7/15-7/24 A continent-sized cloud of hot air and dust originating from the Sahara Desert crossed the Atlantic Ocean and headed towards Florida and the Caribbean. A Saharan Air Layer, or SAL, forms when dry air and dust rise from Africa's west coast and ride the trade winds above the Atlantic Ocean. These dust clouds are not uncommon, especially during the months of July and August. They start when weather patterns called tropical waves pick up dust from the desert in North Africa, carry it a couple of miles into the atmosphere and drift westward. In a sequence of images created by data acquired by the Earth-orbiting Atmospheric Infrared Sounder ranging from July 15 through July 24, we see the distribution of the cloud in the atmosphere as it swirls off of Africa and heads across the ocean to the west. Using the unique silicate spectral signatures of dust in the thermal infrared, AIRS can detect the presence of dust in the atmosphere day or night. This detection works best if there are no clouds present on top of the dust; when clouds are present, they can interfere with the signal, making it much harder to detect dust as in the case of July 24, 2005. In the Quicktime movie, the scale at the bottom of the images shows +1 for dust definitely detected, and ranges down to -1 for no dust detected. The plots are averaged over a number of AIRS observations falling within grid boxes, and so it is possible to obtain fractional numbers. [figure removed for brevity, see original site] Total Water Vapor in the Atmosphere Around the Dust Cloud Click on the image for Quicktime movie The dust cloud is contained within a dry adiabatic layer which originates over the Sahara Desert. This Saharan Air Layer (SAL) advances Westward over the Atlantic Ocean, overriding the cool, moist air nearer the surface. This burst of very dry air is visible in the AIRS retrieved total water

  11. Electrodynamic Dust Shield Demonstrator

    Science.gov (United States)

    Stankie, Charles G.

    2013-01-01

    The objective of the project was to design and manufacture a device to demonstrate a new technology developed by NASA's Electrostatics and Surface Physics Laboratory. The technology itself is a system which uses magnetic principles to remove regolith dust from its surface. This project was to create an enclosure that will be used to demonstrate the effectiveness of the invention to The Office of the Chief Technologist. ONE of the most important challenges of space exploration is actually caused by something very small and seemingly insignificant. Dust in space, most notably on the moon and Mars, has caused many unforeseen issues. Dirt and dust on Earth, while a nuisance, can be easily cleaned and kept at bay. However, there is considerably less weathering and erosion in space. As a result, the microscopic particles are extremely rough and abrasive. They are also electrostatically charged, so they cling to everything they make contact with. This was first noted to be a major problem during the Apollo missions. Dust would stick to the spacesuits, and could not be wiped off as predicted. Dust was brought back into the spacecraft, and was even inhaled by astronauts. This is a major health hazard. Atmospheric storms and other events can also cause dust to coat surfaces of spacecraft. This can cause abrasive damage to the craft. The coating can also reduce the effectiveness of thermal insulation and solar panels.' A group of engineers at Kennedy Space Center's Electrostatics and Surface Physics Laboratory have developed a new technology, called the Electrodynamic Dust Shield, to help alleviate these problems. It is based off of the electric curtain concept developed at NASA in 1967. "The EDS is an active dust mitigation technology that uses traveling electric fields to transport electrostatically charged dust particles along surfaces. To generate the traveling electric fields, the EDS consists of a multilayer dielectric coating with an embedded thin electrode grid

  12. Effects of Particulate Organic Matter Complexation and Photo-Irradiation on the Fate and Toxicity of Mercury(II) in Aqueous Systems

    Science.gov (United States)

    Gelfond, C. E.; Kocar, B. D.; Carrasquillo, A. J.

    2015-12-01

    This project investigates how interactions between mercury (Hg) and particulate organic matter (POM) affect the fate, transport, and toxicity of Hg in the environment. Previous studies have evaluated the coordination of dissolved organic matter (DOM) with Hg, but the coordination of POM with Hg has not been thoroughly addressed. Owing to a high density of reactive functional groups, POM will sorb appreciable quantities of Hg, resulting in a large pool of Hg susceptible to organic matter dependent transformations. Particulate organic carbon is also susceptible photolysis, hence chemical changes induced by irradiation by natural sunlight is also important. Further, photo-reduction of Hg(II) to elemental mercury in the presence of DOM has been observed, yet studies examining this process with Hg(II) complexed to POM are less exhaustive. Here, we illustrate that POM derived from fresh plant detritus is a powerful sorbent of Hg(II), and sorbent properties are altered during POM photolysis. Further, we examine redox transformations of Hg(II), and examine functional groups that contribute to mercury association with POM. Batch sorption isotherms of Hg to dark and irradiated POM from ground Phragmites australis ("common reed") were performed and data was collected using ICP-MS. Coordination of Hg to POM was lower in the irradiated samples, resulting from the decrease in Hg-associated (reduced) sulfur bearing functional groups as measured using X-ray adsorption near-edge spectroscopy (XANES) and extended x-ray adsorption fine structure (EXAFS). Further analysis of the dark and irradiated POM was performed using FT-IR microscopy and STXM to determine changes in distribution and alteration of functional groups responsible for Hg sorption to POM.

  13. Universal instability of dust ion-sound waves and dust-acoustic waves

    International Nuclear Information System (INIS)

    Tsytovich, V.N.; Watanabe, K.

    2002-01-01

    It is shown that the dust ion-sound waves (DISW) and the dust-acoustic waves (DAW) are universally unstable for wave numbers less than some critical wave number. The basic dusty plasma state is assumed to be quasi-neutral with balance of the plasma particle absorption on the dust particles and the ionization with the rate proportional to the electron density. An analytical expression for the critical wave numbers, for the frequencies and for the growth rates of DISW and DAW are found using the hydrodynamic description of dusty plasma components with self-consistent treatment of the dust charge variations and by taking into account the change of the ion and electron distributions in the dust charging process. Most of the previous treatment do not take into account the latter process and do not treat the basic state self-consistently. The critical lengths corresponding to these critical wave numbers can be easily achieved in the existing experiments. It is shown that at the wave numbers larger than the critical ones DISW and DAW have a large damping which was not treated previously and which can be also measured. The instabilities found in the present work on their non linear stage can lead to formation of different types of dust self-organized structures. (author)

  14. Epoxy composite dusts with and without carbon nanotubes cause similar pulmonary responses, but differences in liver histology in mice following pulmonary deposition

    DEFF Research Database (Denmark)

    Saber, Anne Thoustrup; Mortensen, Alicja; Szarek, Jozef

    2016-01-01

    Background: The toxicity of dusts from mechanical abrasion of multi-walled carbon nanotube (CNT) epoxy nanocomposites is unknown. We compared the toxic effects of dusts generated by sanding of epoxy composites with and without CNT. The used CNT type was included for comparison.Methods: Mice recei...

  15. Estimate of safe human exposure levels for lunar dust based on comparative benchmark dose modeling.

    Science.gov (United States)

    James, John T; Lam, Chiu-Wing; Santana, Patricia A; Scully, Robert R

    2013-04-01

    Brief exposures of Apollo astronauts to lunar dust occasionally elicited upper respiratory irritation; however, no limits were ever set for prolonged exposure to lunar dust. The United States and other space faring nations intend to return to the moon for extensive exploration within a few decades. In the meantime, habitats for that exploration, whether mobile or fixed, must be designed to limit human exposure to lunar dust to safe levels. Herein we estimate safe exposure limits for lunar dust collected during the Apollo 14 mission. We instilled three respirable-sized (∼2 μ mass median diameter) lunar dusts (two ground and one unground) and two standard dusts of widely different toxicities (quartz and TiO₂) into the respiratory system of rats. Rats in groups of six were given 0, 1, 2.5 or 7.5 mg of the test dust in a saline-Survanta® vehicle, and biochemical and cellular biomarkers of toxicity in lung lavage fluid were assayed 1 week and one month after instillation. By comparing the dose--response curves of sensitive biomarkers, we estimated safe exposure levels for astronauts and concluded that unground lunar dust and dust ground by two different methods were not toxicologically distinguishable. The safe exposure estimates were 1.3 ± 0.4 mg/m³ (jet-milled dust), 1.0 ± 0.5 mg/m³ (ball-milled dust) and 0.9 ± 0.3 mg/m³ (unground, natural dust). We estimate that 0.5-1 mg/m³ of lunar dust is safe for periodic human exposures during long stays in habitats on the lunar surface.

  16. A study of the uptake and toxicity of some stable and radioactive pollutants in marine organisms: antimony, silver, cobalt and strontium in mollusks, crustaceans and teleosts

    International Nuclear Information System (INIS)

    Amiard, J.-C.

    1978-10-01

    Qualitative and quantitative results following direct aquatic contamination of mollusks, crustaceans and teleosts by 125 Sb, 110 Ag, 60 Co, 85 Sr are reported. The effects of a number of biotic and abiotic parameters on the contamination of the various organisms and the distribution and elimination of the radionuclides in the tissues were investigated. The transfer of sup(110m)Ag, 60 Co and 125 Sb was studied in several benthic food chains. The transfer factor (F.T.) between a given trophic level and the initial environment (seawater) was determined as well as various physiological parameters (percentages ingested, assimilated, eliminated via the feces or urine and/or the gills. Elimination and tissue uptake were followed in mollusks and crustaceans. The consequences of contamination by stable and radioactive pollutants on plants and animals were considered. Acute (lethal) toxicity of various metals or metalloids on marine organisms were quantified. More sensitive sublethal tests considering physiological functions or behaviour were used. Irradiation doses to experiment animals were calculated, showing the importance of the (internal or external distribution of radionuclides and individual geometries on the total exposure dose [fr

  17. Effects of toxic organic flotation reagent (aniline aerofloat) on an A/O submerged membrane bioreactor (sMBR): Microbial community dynamics and performance.

    Science.gov (United States)

    Lin, Weixiong; Sun, Shuiyu; Wu, Chun; Xu, Pingting; Ye, Ziwei; Zhuang, Shengwei

    2017-08-01

    Bio-treatment of flotation wastewater has been proven to be both effective and economical, as a treatment method. Despite this, little is known regarding the effects of toxic organic floatation reagents such as Dianilinodithiophosphoric acid (DDA), on the microbial community performance or dynamics, which are critical to the effective performance of the bio-treatment reactor. A submerged membrane bioreactor (sMBR) was constructed to continuously treat simulated wastewater contaminated with DDA, an organic flotation reagent that is now considered a significant pollutant. The performance of the sMBR system was investigated at different DDA loading concentrations, with assessment of the effects of DDA on the microbial communities within the sMBR, in particular the biodiversity and succession within the microbial community. Results showed that, with increased DDA loadings, the performance of the sMBR was initially negatively affected, but the system adapted efficiently and consistently reached a COD removal rate of up to 80%. Increased DDA loading concentrations had an adverse effect on the activity of both the activated sludge and microbial communities, resulting in a large alteration in microbial dynamics, especially during the start-up stage and the high DDA loading stage. Strains capable of adapting to the presence of DDA, capable of degrading DDA or utilizing its byproducts, were enriched within the sMBR community, such as Zoogloea, Clostridium, Sideroxydans lithotrophicus, Thiobacillus, Thauera amino aromatica and Alicycliphilus denitrificans. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Dust in planetary nebulae

    International Nuclear Information System (INIS)

    Kwok, S.

    1980-01-01

    A two-component dust model is suggested to explain the infrared emission from planetary nebulae. A cold dust component located in the extensive remnant of the red-giant envelope exterior to the visible nebula is responsible for the far-infrared emission. A ward dust component, which is condensed after the formation of the planetary nebula and confined within the ionized gas shell, emits most of the near- and mid-infrared radiation. The observations of NGC 7027 are shown to be consisten with such a model. The correlation of silicate emission in several planetary nebulae with an approximately +1 spectral index at low radio frequencies suggests that both the silicate and radio emissions originate from the remnant of the circumstellar envelope of th precursor star and are observable only while the planetary nebula is young. It is argued that oxygen-rich stars as well as carbon-rich stars can be progenitors of planetary nebulae

  19. Interstellar dust and extinction

    International Nuclear Information System (INIS)

    Mathis, J.S.

    1990-01-01

    It is noted that the term interstellar dust refers to materials with rather different properties, and that the mean extinction law of Seaton (1979) or Savage and Mathis (1979) should be replaced by the expression given by Cardelli et al. (1989), using the appropriate value of total-to-selective extinction. The older laws were appropriate for the diffuse ISM but dust in clouds differs dramatically in its extinction law. Dust is heavily processed while in the ISM by being included within clouds and cycled back into the diffuse ISM many times during its lifetime. Hence, grains probably reflect only a trace of their origin, although meteoritic inclusions with isotopic anomalies demonstrate that some tiny particles survive intact from a supernova origin to the present. 186 refs

  20. Dust control for draglines

    Energy Technology Data Exchange (ETDEWEB)

    Grad, P.

    2009-09-15

    Monitoring dust levels inside draglines reveals room for improvement in how filtration systems are used and maintained. The Australian firm BMT conducted a field test program to measure airflow parameters, dust fallout rates and dust concentrations, inside and outside the machine house, on four draglines and one shovel. The study involved computational fluid dynamics (CFD) simulations. The article describes how the tests were made and gives results. It was not possible to say which of the two main filtration systems currently used on Australian draglines - Dynavane or Floseps - performs better. It would appear that more frequent maintenance and cleaning would increase the overall filtration performance and systems could be susceptible to repeat clogging in a short time. 2 figs., 1 photos.

  1. DustEM: Dust extinction and emission modelling

    Science.gov (United States)

    Compiègne, M.; Verstraete, L.; Jones, A.; Bernard, J.-P.; Boulanger, F.; Flagey, N.; Le Bourlot, J.; Paradis, D.; Ysard, N.

    2013-07-01

    DustEM computes the extinction and the emission of interstellar dust grains heated by photons. It is written in Fortran 95 and is jointly developed by IAS and CESR. The dust emission is calculated in the optically thin limit (no radiative transfer) and the default spectral range is 40 to 108 nm. The code is designed so dust properties can easily be changed and mixed and to allow for the inclusion of new grain physics.

  2. Size Distributions and Formation Pathways of Organic and Inorganic Constituents in Spring Aerosols from Okinawa Island in the Western North Pacific Rim: An Outflow Region of Asian Dusts

    Science.gov (United States)

    Deshmukh, D. K.; Lazaar, M.; Kawamura, K.; Kunwar, B.; Tachibana, E.; Boreddy, S. K. R.

    2015-12-01

    Size-segregated aerosols (9-stages) were collected at Okinawa Island in the western North Pacific Rim in spring 2008. The samples were analyzed for diacids (C2-C12), ω-oxoacids (ωC2-ωC9), a-dicarbonyls (C2-C3), organic carbon (OC), water-soluble OC (WSOC) and major ions to understand the sources and atmospheric processes in the outflow region of Asian pollutants. The molecular distribution of diacids showed the predominance of oxalic acid (C2) followed by malonic and succinic acids in all the size-segregated aerosols. ω-Oxoacids showed the predominance of glyoxylic acid (ωC2) whereas glyoxal (Gly) was more abundant than methylglyoxal in all the sizes. The abundant presence of sulfate as well as phthalic and adipic acids in Okinawa aerosols suggested a significant contribution of anthropogenic sources in East Asia via long-range atmospheric transport. Diacids (C2-C5), ωC2 and Gly as well as WSOC and OC peaked at 0.65-1.1 µm in fine mode whereas azelaic (C9) and 9-oxononanoic (ωC9) acids peaked at 3.3-4.7 µm in coarse mode. Sulfate and ammonium are enriched in fine mode whereas sodium and chloride are in coarse mode. An important mechanism for the formation of these organic species in Okinawa aerosols is probably gas phase oxidation of VOCs and subsequent in-cloud processing during long-range transport. Their characteristics size distribution implies that fine particles enriched with these organic and inorganic species could act as CCN to develop the cloud cover over the western North Pacific. The major peak of C9 and ωC9 on coarse mode suggest that they are produced by photooxidation of unsaturated fatty acids mainly derived from phytoplankton via heterogeneous reactions on sea spray particles. This study demonstrates that anthropogenic aerosols emitted from East Asia have significant influence on the compositions of organic and inorganic aerosols in the western North Pacific Rim.

  3. Two Cases of Tsunami Dust Pneumonia: Organizing Pneumonia Caused by the Inhalation of Dried Tsunami Sludge after the 2011 Great East Japan Earthquake

    Science.gov (United States)

    Yamanda, Shinsuke; Kobayashi, Seiichi; Hanagama, Masakazu; Sato, Hikari; Suzuki, Satoshi; Ueda, Shinsaku; Takahashi, Toru; Yanai, Masaru

    2016-01-01

    We report two cases of organizing pneumonia (OP) secondary to the inhalation of the dried tsunami sludge which formed during the 2011 Great East Japan Earthquake and the consequent tsunami. After the disaster, both of these patients had been engaged in the restoration work. About half a month later, they developed shortness of breath and pulmonary infiltrates. These patients were diagnosed with interstitial pneumonia. Their biopsy specimens revealed multifocal peribronchiolitis and OP. An electron probe microanalysis of these specimens demonstrated the presence of elements from the earth's crust in the inflammatory lesions. These two cases indicate that exposure to dried tsunami sludge can cause OP. PMID:27980267

  4. Assessing the toxicity of Pb- and Sn-based perovskite solar cells in model organism Danio rerio

    Science.gov (United States)

    Babayigit, Aslihan; Duy Thanh, Dinh; Ethirajan, Anitha; Manca, Jean; Muller, Marc; Boyen, Hans-Gerd; Conings, Bert

    2016-01-01

    Intensive development of organometal halide perovskite solar cells has lead to a dramatic surge in power conversion efficiency up to 20%. Unfortunately, the most efficient perovskite solar cells all contain lead (Pb), which is an unsettling flaw that leads to severe environmental concerns and is therefore a stumbling block envisioning their large-scale application. Aiming for the retention of favorable electro-optical properties, tin (Sn) has been considered the most likely substitute. Preliminary studies have however shown that Sn-based perovskites are highly unstable and, moreover, Sn is also enlisted as a harmful chemical, with similar concerns regarding environment and health. To bring more clarity into the appropriateness of both metals in perovskite solar cells, we provide a case study with systematic comparison regarding the environmental impact of Pb- and Sn-based perovskites, using zebrafish (Danio Rerio) as model organism. Uncovering an unexpected route of intoxication in the form of acidification, it is shown that Sn based perovskite may not be the ideal Pb surrogate.

  5. Comprehensive review on toxicity of persistent organic pollutants from petroleum refinery waste and their degradation by microorganisms.

    Science.gov (United States)

    Varjani, Sunita J; Gnansounou, Edgard; Pandey, Ashok

    2017-12-01

    Control and prevention of environmental pollution has become a worldwide issue of concern. Aromatic hydrocarbons including benzene, toluene, ethyl benzene, xylene (BTEX) and polyaromatic hydrocarbons (PAHs) are persistent organic pollutants (POPs), released into the environment mainly by exploration activities of petroleum industry. These pollutants are mutagenic, carcinogenic, immunotoxic and teratogenic to lower and higher forms of life i.e. microorganisms to humans. According to the International Agency for Research on Cancer (IARC) and United States Environmental Protection Agency (U.S. EPA), Benzo[a]pyrene (BaP) is carcinogenic in laboratory animals and humans. Aromatic hydrocarbons are highly lipid soluble and thus readily absorbed from environment in gastrointestinal tract of mammals. Treatment and remediation of petroleum refinery waste have been shown either to reduce or to eliminate genotoxicity of these pollutants. Bioremediation by using microorganisms to treat this waste is showing a promising technology as it is safe and cost-effective option among various technologies tested. The main aim of this review is to provide contemporary information on variety of aromatic hydrocarbons present in crude oil (with special focus to mono- and poly-aromatic hydrocarbons), exposure routes and their adverse effects on humans. This review also provides a synthesis of scientific literature on remediation technologies available for aromatic hydrocarbons, knowledge gaps and future research developments in this field. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Assessing the toxicity of Pb- and Sn-based perovskite solar cells in model organism Danio rerio

    Science.gov (United States)

    Babayigit, Aslihan; Duy Thanh, Dinh; Ethirajan, Anitha; Manca, Jean; Muller, Marc; Boyen, Hans-Gerd; Conings, Bert

    2016-01-01

    Intensive development of organometal halide perovskite solar cells has lead to a dramatic surge in power conversion efficiency up to 20%. Unfortunately, the most efficient perovskite solar cells all contain lead (Pb), which is an unsettling flaw that leads to severe environmental concerns and is therefore a stumbling block envisioning their large-scale application. Aiming for the retention of favorable electro-optical properties, tin (Sn) has been considered the most likely substitute. Preliminary studies have however shown that Sn-based perovskites are highly unstable and, moreover, Sn is also enlisted as a harmful chemical, with similar concerns regarding environment and health. To bring more clarity into the appropriateness of both metals in perovskite solar cells, we provide a case study with systematic comparison regarding the environmental impact of Pb- and Sn-based perovskites, using zebrafish (Danio Rerio) as model organism. Uncovering an unexpected route of intoxication in the form of acidification, it is shown that Sn based perovskite may not be the ideal Pb surrogate. PMID:26759068

  7. Dust-Plasma Interactions

    International Nuclear Information System (INIS)

    Rosenberg, M.

    2010-01-01

    The objective of our theoretical research under this grant over the past 3 years was to develop new understanding in a range of topics in the physics of dust-plasma interactions, with application to space and the laboratory. We conducted studies related to the physical properties of dust, waves and instabilities in both weakly coupled and strongly coupled dusty plasmas, and innovative possible applications. A major consideration in our choice of topics was to compare theory with experiments or observations, and to motivate new experiments, which we believe is important for developing this relatively new field. Our research is summarized, with reference to our list of journal publications.

  8. Microbial degradation of coconut coir dust for biomass production

    Energy Technology Data Exchange (ETDEWEB)

    Uyenco, F.R.; Ochoa, J.A.K.

    Several species of white-rot fungi were studied for its ability to degrade the lignocellulose components of coir dust at optimum conditions. The most effective fungi was Phanerochaeta chrysosporium UPCC 4003. This organism degraded the lignocellulose complex of coir dust at a rate of about 25 percent in 4 weeks. The degradation process was carried on with minimal nitrogen concentration, coconut water supplementation and moisture levels between 85-90 percent. Shake flask cultures of the degraded coir dust using cellulolytic fungi were not effective. In fermentor cultures with Chaetomium cellulolyticum UPCC 3934, supplemented coir dust was converted into a microbial biomass product (MBP) with 15.58 percent lignin, 19.20 percent cellulose and 18.87 percent protein. More work is being done on the utilization of coir dust on a low technology.

  9. Toxicity of organic compounds to marine invertebrate embryos and larvae: a comparison between the sea urchin embryogenesis bioassay and alternative test species.

    Science.gov (United States)

    Bellas, Juan; Beiras, Ricardo; Mariño-Balsa, José Carlos; Fernández, Nuria

    2005-04-01

    This study investigated the toxic effects of the insecticides lindane and chlorpyrifos, the herbicide diuron, the organometallic antifoulant tributyltin (TBT), and the surfactant sodium dodecyl sulfate (SDS) on the early life stages of Paracentrotus lividus (Echinodermata, Euechinoidea), Ciona intestinalis (Chordata, Ascidiacea), Maja squinado and Palaemon serratus (Arthropoda, Crustacea) in laboratory acute toxicity tests. The assays studied embryogenesis success from fertilized egg to normal larvae in P. lividus (48 h incubation at 20 degrees C) and C. intestinalis (24 h incubation at 20 degrees C), and larval mortality at 24 and 48 h in M. squinado and P. serratus. For P. lividus, the median effective concentrations (EC50) reducing percentages of normal larvae by 50% were: 350 microg l(-1) for chlorpyrifos, 5500 microg l(-1) for diuron, 4277 microg l(-1) for SDS, and 0.309 microg l(-1) for TBT. For C. intestinalis, the EC50 values affecting embryogenesis success were 5666 microg l(-1) for chlorpyrifos, 24,397 microg (l-1) for diuron, 4412 microg l(-1) for lindane, 5145 microg I(-1) for SDS, and 7.1 microg l(-1) for TBT. The median lethal concentrations (LC50) for M. squinado larval survival were 0.84 microg l(-1) (24 h) and 0.79 microg l(-1) (48 h) for chlorpyrifos, 2.23 microg(l(-1) (24 h) and 2.18 microg l(-1) (48 h) for lindane, and 687 microg l(-1) (48 h) for SDS. For P. serratus the LC50 values obtained were 0.35 microg l(-1) (24 h) and 0.22 microg l(-1) (48 h) for chlorpyrifos, 3011 microg l(-1) (24 h) and 3044 microg l(-1) (48 h) for diuron, 5.20 microg l(-1) (24 h) and 5.59 microg l(-1) (48 h) for lindane, and 22.30 microg l(-1) (24 h) and 17.52 microg l(-1) (48 h) for TBT. Decapod larvae, as expected, were markedly more sensitive to the insecticides than sea urchins and ascidians, and SDS was the least toxic compound tested for these organisms. Lowest observed effect concentrations (LOEC) of TBT for sea urchin and ascidian embryos, chlorpyrifos and

  10. Control of harmful dust in coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, B; Bower, K; Mitchell, D

    1973-01-01

    This handbook consists of a series of short chapters devoted to: sources of airborne dust; dust standards and methods of sampling; dust prevention on mechanized faces; ventilation and dust extraction; distribution and use of water; dust control on mechanized faces; dust control in drivages and headings; drilling and shotfiring; dust control in transport; some outbye dust control techniques (hygroscopic salts, impingement curtains); water infusion; personal protective equipment. (CIS Abstr.)

  11. Dust evolution in protoplanetary disks

    OpenAIRE

    Gonzalez , Jean-François; Fouchet , Laure; T. Maddison , Sarah; Laibe , Guillaume

    2007-01-01

    6 pages, 5 figures, to appear in the Proceedings of IAU Symp. 249: Exoplanets: Detection, Formation and Dynamics (Suzhou, China); International audience; We investigate the behaviour of dust in protoplanetary disks under the action of gas drag using our 3D, two-fluid (gas+dust) SPH code. We present the evolution of the dust spatial distribution in global simulations of planetless disks as well as of disks containing an already formed planet. The resulting dust structures vary strongly with pa...

  12. Respirable versus inhalable dust sampling

    International Nuclear Information System (INIS)

    Hondros, J.

    1987-01-01

    The ICRP uses a total inhalable dust figure as the basis of calculations on employee lung dose. This paper was written to look at one aspect of the Olympic Dam dust situation, namely, the inhalable versus respirable fraction of the dust cloud. The results of this study will determine whether it is possible to use respirable dust figures, as obtained during routine monitoring to help in the calculations of employee exposure to internal radioactive contaminants

  13. Paleo-dust insights onto dust-climate interactions

    Science.gov (United States)

    Albani, S.; Mahowald, N. M.

    2017-12-01

    Mineral dust emissions are affected by changing climate conditions, and in turn dust impacts the atmospheric radiation budget, clouds and biogeochemical cycles. Climate and public health dust-related issues call for attention on the fate of the dust cycle in the future, and the representation of the dust cycle is now part of the strategy of the Paleoclimate Modelling Intercomparison Project phase 4 and the Coupled Model Intercomparison Project phase 6 (PMIP4-CMIP6). Since mineral aerosols are one of the most important natural aerosols, understanding past dust responses to climate in the paleoclimate will allow us to better understand mineral aerosol feedbacks with climate and biogeochemistry in the Anthropocene. Modern observations and paleoclimate records offer the possibility of multiple, complementary views on the global dust cycle, and allow to validate and/or constrain the numerical representation of dust in climate and Earth system models. We present our results from a set of simulations with the Community Earth System Model for different climate states, including present and past climates such as the pre-industrial, the mid-Holocene and the Last Glacial Maximum. A set of simulations including a prognostic dust cycle was thoroughly compared with a wide set of present day observations from different platforms and regions, in order to realistically constrain the magnitude of dust load, surface concentration, deposition, optical properties, and particle size distributions. The magnitude of emissions for past climate regimes was constrained based on compilations of paleodust mass accumulation rates and size distributions, as well as based on information on dust provenance. The comparison with a parallel set of simulations without dust allows estimating the impacts of dust on surface climate. We analyze impacts of dust on the mean and variability of surface temperature and precipitation in each climate state, as well as the impacts that changing dust emissions had

  14. Injurious effects of wool and grain dusts on alveolar epithelial cells and macrophages in vitro.

    Science.gov (United States)

    Brown, D M; Donaldson, K

    1991-01-01

    Epidemiological studies of workers in wool textile mills have shown a direct relation between the concentration of wool dust in the air and respiratory symptoms. Injurious effects of wool dust on the bronchial epithelium could be important in causing inflammation and irritation. A pulmonary epithelial cell line in vitro was therefore used to study the toxic effects of wool dust. Cells of the A549 epithelial cell line were labelled with 51Cr and treated with whole wool dusts and extracts of wool, after which injury was assessed. Also, the effects of grain dust, which also causes a form of airway obstruction, were studied. The epithelial injury was assessed by measuring 51Cr release from cells as an indication of lysis, and by monitoring cells which had detached from the substratum. No significant injury to A549 cells was caused by culture with any of the dusts collected from the air but surface "ledge" dust caused significant lysis at some doses. Quartz, used as a toxic control dust, caused significant lysis at the highest concentration of 100 micrograms/well. To determine whether any injurious material was soluble the dusts were incubated in saline and extracts collected. No extracts caused significant injury to epithelial cells. A similar lack of toxicity was found when 51Cr labelled control alveolar macrophages were targets for injury. Significant release of radiolabel was evident when macrophages were exposed to quartz at concentrations of 10 and 20 micrograms/well, there being no significant injury with either wool or grain dusts. These data suggest that neither wool nor grain dust produce direct injury to epithelial cells, and further studies are necessary to explain inflammation leading to respiratory symptoms in wool and grain workers. PMID:2015211

  15. Erosion of dust aggregates

    NARCIS (Netherlands)

    Seizinger, A.; Krijt, S.; Kley, W.

    2013-01-01

    Aims: The aim of this work is to gain a deeper insight into how much different aggregate types are affected by erosion. Especially, it is important to study the influence of the velocity of the impacting projectiles. We also want to provide models for dust growth in protoplanetary disks with simple

  16. Dust-Plasma Interactions

    International Nuclear Information System (INIS)

    Rosenberg, Marelene

    2005-01-01

    Our theoretical research on dust-plasma interactions has concentrated on three main areas: (a)studies of grain charging and applications; (b) waves and instabilities in weakly correlated dusty plasma with applications to space and laboratory plasmas; (c) waves in strongly coupled dusty plasmas.

  17. Magnetic studies of dusts in the urban environment

    International Nuclear Information System (INIS)

    Xie, S.

    2000-12-01

    Dusts are one of the major public health concerns in the urban environment. This study investigates the application of magnetic techniques in the studies of urban dust pollution. Measurements of magnetic properties, element concentrations, and the organic matter content were carried out on Liverpool (UK) street dust and/or Bootle (UK) deposited dust. Mixed dominant ferrimagnetic phases are found in Liverpool street dust although magnetite is probably a major one. The partial susceptibility technique is able to model the contributions of main magnetic components satisfactorily in Liverpool street dust. There are similar spatial distributions for some measurements, such as χLF and Pb, whilst there are different patterns for some measurements, such as χLF and the organic matter content. There are good linear correlations between the organic matter content and some magnetic mineral concentration-related parameters for < 1mm (bulk) samples. Among them, frequency dependent susceptibility (χFD) shows the highest correlation coefficient value. χFD percentage demonstrates a significant correlation with the organic matter content for size fraction and bulk samples. This suggests that re-entrainment of soil is probably a major source of the organic material present in street dust. The ratio χARM /SIRM shows a highly significant correlation with the organic matter content for <150μm fraction samples. The study demonstrates that the simple, rapid, and non-destructive magnetic measurements may be used as proxies for the organic matter content in street dust. Associations between magnetic properties and element concentrations are investigated by using correlation analysis and factor analysis, which may be a potential approach for source identification of magnetic material in the environment. The study suggests that ferrimagnetic minerals are the dominant magnetic component in Bootle dust samples. Both studied sites show similar magnetic properties, but they can be

  18. Comparative In Vitro Biological Toxicity of Four Kinds of Air Pollution Particles.

    Science.gov (United States)

    Shin, Han-Jae; Cho, Hyun Gi; Park, Chang Kyun; Park, Ki Hong; Lim, Heung Bin

    2017-10-01

    Accumulating epidemiological evidence indicates that exposure to fine air pollution particles (APPs) is associated with a variety of adverse health effects. However, the exact physiochemical properties and biological toxicities of fine APPs are still not well characterized. We collected four types of fine particle (FP) (diesel exhaust particles [DEPs], natural organic combustion [NOC] ash, synthetic organic combustion [SOC] ash, and yellow sand dust [YSD]) and investigated their physicochemical properties and in vitro biological toxicity. DEPs were almost entirely composed of ultrafine particles (UFPs), while the NOC, SOC, and YSD particles were a mixture of UFPs and FPs. The main elements in the DEPs, NOC ash, SOC ash, and YSD were black carbon, silicon, black carbon, and silicon, respectively. DEPs exhibited dose-dependent mutagenicity even at a low dose in Salmonella typhimurium TA 98 and 100 strains in an Ames test for genotoxicity. However, NOC, SOC, and YSD particles did not show any mutagenicity at high doses. The neutral red uptake assay to test cell viability revealed that DEPs showed dose-dependent potent cytotoxicity even at a low concentration. The toxicity of DEPs was relatively higher than that of NOC, SOC, and YSD particles. Therefore, these results indicate that among the four FPs, DEPs showed the highest in vitro biological toxicity. Additional comprehensive research studies such as chemical analysis and in vivo acute and chronic inhalation toxicity tests are necessary to determine and clarify the effects of this air contaminant on human health.

  19. A survey of spatially distributed exterior dust lead loadings in New York City

    Energy Technology Data Exchange (ETDEWEB)

    Caravanos, Jack [Hunter College-CUNY, School of Health Sciences (United States); Weiss, Arlene L [Environmental Medicine Inc., 263 Center Avenue, Westwood, NJ 07675 (United States); School of Medicine, New York University, NY 10016 (United States); Blaise, Marc J [Hunter College-CUNY, School of Health Sciences (United States); Jaeger, Rudolph J [Environmental Medicine Inc., 263 Center Avenue, Westwood, NJ 07675 (United States) and School of Medicine, New York University, NY 10016 (United States)

    2006-02-15

    This work documents ambient lead dust deposition values (lead loading) for the boroughs of New York City in 2003-2004. Currently, no regulatory standards exist for exterior concentrations of lead in settled dust. This is in contrast to the clearance and risk assessment standards that exist for interior residential dust. The reported potential for neurobehavioral toxicity and adverse cognitive development in children due to lead exposure prompts public health concerns about undocumented lead sources. Such sources may include settled dust of outdoor origin. Dust sampling throughout the five boroughs of NYC was done from the top horizontal portion of pedestrian traffic control signals (PTCS) at selected street intersections along main thoroughfares. The data (n=214 samples) show that lead in dust varies within each borough with Brooklyn having the highest median concentration (730{mu}g/ft{sup 2}), followed in descending order by Staten Island (452{mu}g/ft{sup 2}), the Bronx (382{mu}g/ft{sup 2}), Queens (198{mu}g/ft{sup 2}) and finally, Manhattan (175{mu}g/ft{sup 2}). When compared to the HUD/EPA indoor lead in dust standard of 40{mu}g/ft{sup 2}, our data show that this value is exceeded in 86% of the samples taken. An effort was made to determine the source of the lead in the dust atop of the PTCS. The lead in the dust and the yellow signage paint (which contains lead) were compared using isotopic ratio analysis. Results showed that the lead-based paint chip samples from intact signage did not isotopically match the dust wipe samples taken from the same surface. We know that exterior dust containing lead contributes to interior dust lead loading. Therefore, settled leaded dust in the outdoor environment poses a risk for lead exposure to children living in urban areas, namely, areas with elevated childhood blood lead levels and background lead dust levels from a variety of unidentified sources.

  20. A survey of spatially distributed exterior dust lead loadings in New York City

    International Nuclear Information System (INIS)

    Caravanos, Jack; Weiss, Arlene L.; Blaise, Marc J.; Jaeger, Rudolph J.

    2006-01-01

    This work documents ambient lead dust deposition values (lead loading) for the boroughs of New York City in 2003-2004. Currently, no regulatory standards exist for exterior concentrations of lead in settled dust. This is in contrast to the clearance and risk assessment standards that exist for interior residential dust. The reported potential for neurobehavioral toxicity and adverse cognitive development in children due to lead exposure prompts public health concerns about undocumented lead sources. Such sources may include settled dust of outdoor origin. Dust sampling throughout the five boroughs of NYC was done from the top horizontal portion of pedestrian traffic control signals (PTCS) at selected street intersections along main thoroughfares. The data (n=214 samples) show that lead in dust varies within each borough with Brooklyn having the highest median concentration (730μg/ft 2 ), followed in descending order by Staten Island (452μg/ft 2 ), the Bronx (382μg/ft 2 ), Queens (198μg/ft 2 ) and finally, Manhattan (175μg/ft 2 ). When compared to the HUD/EPA indoor lead in dust standard of 40μg/ft 2 , our data show that this value is exceeded in 86% of the samples taken. An effort was made to determine the source of the lead in the dust atop of the PTCS. The lead in the dust and the yellow signage paint (which contains lead) were compared using isotopic ratio analysis. Results showed that the lead-based paint chip samples from intact signage did not isotopically match the dust wipe samples taken from the same surface. We know that exterior dust containing lead contributes to interior dust lead loading. Therefore, settled leaded dust in the outdoor environment poses a risk for lead exposure to children living in urban areas, namely, areas with elevated childhood blood lead levels and background lead dust levels from a variety of unidentified sources

  1. Modelling dust transport in tokamaks

    International Nuclear Information System (INIS)

    Martin, J.D.; Martin, J.D.; Bacharis, M.; Coppins, M.; Counsell, G.F.; Allen, J.E.; Counsell, G.F.

    2008-01-01

    The DTOKS code, which models dust transport through tokamak plasmas, is described. The floating potential and charge of a dust grain in a plasma and the fluxes of energy to and from it are calculated. From this model, the temperature of the dust grain can be estimated. A plasma background is supplied by a standard tokamak edge modelling code (B2SOLPS5.0), and dust transport through MAST (the Mega-Amp Spherical Tokamak) and ITER plasmas is presented. We conclude that micron-radius tungsten dust can reach the separatrix in ITER. (authors)

  2. Hydrometallurgical treatment of copper smelter dusts. Desarsenification of leaching solutions

    International Nuclear Information System (INIS)

    Alguacil, F.J.; Magne, L.; Navarro, P.; Simpson, J.

    1996-01-01

    Copper smelter dusts contain along with this metal, which is amenable for its recovery, a number of other metals (especially arsenic) which are considered as toxic. Different alternatives have been proposed for the treatment of such metallurgical residues and among them Hydrometallurgy shows good perspectives for its application in this field. In the present work different hydrometallurgical processes proposed for the treatment of copper smelter dusts are described and evaluated together with different alternatives given for the Desarsenification of the leaching solutions. (Author) 36 refs

  3. Dust resuspension and transport modeling for loss of vacuum accidents

    International Nuclear Information System (INIS)

    Humrickhouse, P.W.; Corradini, M.L.; Sharpe, J.P.

    2007-01-01

    Plasma surface interactions in tokamaks are known to create significant quantities of dust, which settles onto surfaces and accumulates in the vacuum vessel. In ITER, a loss of vacuum accident may result in the release of dust which will be radioactive and/or toxic, and provides increased surface area for chemical reactions or dust explosion. A new method of analysis has been developed for modeling dust resuspension and transport in loss of vacuum accidents. The aerosol dynamic equation is solved via the user defined scalar (UDS) capability in the commercial CFD code Fluent. Fluent solves up to 50 generic transport equations for user defined scalars, and allows customization of terms in these equations through user defined functions (UDF). This allows calculation of diffusion coefficients based on local flow properties, inclusion of body forces such as gravity and th