WorldWideScience

Sample records for assessing vegetation toxicity

  1. Review: Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops

    Institute of Scientific and Technical Information of China (English)

    ISLAM Ejaz ul; YANG Xiao-e; HE Zhen-li; MAHMOOD Qaisar

    2007-01-01

    Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants,particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary

  2. Assessment of freshwater sediment toxicity from enhanced anaerobic vegetable oil degradation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K.; Wohlgeschaffen, G.; King, T.; Cobanli, S.E. [Department of Fisheries and Oceans, Dartmouth, NS (Canada). Bedford Inst. of Oceanography; Doe, K.G.; Jackman, P.M. [Environment Canada, Moncton, NB (Canada). Environmental Conservation Branch; Wrenn, B.A.; Li, Z. [Washington Univ., St. Louis, MO (United States). Dept. of Civil Engineering; Venosa, A. [United States Environmental Protection Agency, Cincinnati, OH (United States)

    2004-07-01

    This study addressed some of the concerns associated with a proposed vegetable oil spill remediation method for use in aquatic environments. The method involves the addition of clay to mediate the transport of oil to the sediment where anaerobic microorganisms decompose it. There is concern that oleic acid and metabolic by products in the oil may be toxic. This study monitored the biodegradation and toxicity of canola oil within anaerobic sediments in replicate test chambers using Microtox{sup R} and amphipods bioassays. Anaerobic degradation was confirmed through gravimetric analysis of the residual oil and measurements of methane production. The Microtox{sup R} Solid-Phase Test indicated a trend towards the depression of EC50 values with higher oil concentrations at T=0. Both the oiled treatments had elevated toxicity levels after 2 weeks, but the sediments were found to recover to control levels after 2 months. Monitoring of survival and growth patterns of the amphipods assays showed similar trends. The results indicate that concerns are unfounded regarding the production of free fatty acids and other toxic metabolites from anaerobic hydrolysis of vegetable oil triglycerides in the proposed spill countermeasure.

  3. Application of principal component analysis in the assessment of essential and toxic metals in vegetable and soil from polluted and referent areas

    OpenAIRE

    Balabanova, Biljana; Stafilov, Trajče; Baceva, Katerina

    2015-01-01

    The aim of the paper is to assess the 23 elements distribution in agricultural soil and vegetables [garlic (Allium sativum), onion (Allium cepa) and parsley (Petroselinum crispum)] widely used as food in areas contaminated with toxic metals due to long-lasting copper mining activities in the Republic of Macedonia. Principal components analysis (PCA) models were computed with different variables: elements contents in vegetables and soil samples collected from contaminated and uncontaminated...

  4. Rapid bioassessment methods for assessing vegetation toxicity at the Savannah River Site - germination tests and root elongation trials

    Energy Technology Data Exchange (ETDEWEB)

    Specht, W.L.; Klaine, S.J.; Hook, D.D. [and others

    1996-01-01

    Plants form the basis of all ecosystems including wetlands. Although they are the most abundant life form and are the primary producers for all other organisms, they have received the least attention when it comes to environmental matters. Higher plants have rarely been used in ecotoxicity testing and may not respond in the same manner as algae, which have been used more frequently. The introduction of hazardous waste materials into wetland areas has the potential to alter and damage the ecological processes in these ecosystems. Measuring the impact of these contaminants on higher plants is therefore important and needs further research. Higher plants are useful for detecting both herbicidal toxicity and heavy metal toxicity. For phytotoxicity tests to be practical they must be simple, inexpensive, yet sensitive to a variety of contaminants. A difference between seed germination and root elongation tests is that seed germination tests measure toxicity associated with soils directly, while root elongation tests consider the indirect effects of water-soluble constituents that may be present in site samples.

  5. Hazard assessment of vegetated slopes

    NARCIS (Netherlands)

    J.E. Norris; J.R. Greenwood; A. Achim; B.A. Gardiner; B.C. Nicoll; E. Cammeraat; S.B. Mickovski

    2008-01-01

    The hazard assessment of vegetated slopes are reviewed and discussed in terms of the stability of the slope both with and without vegetation, soil erosion and the stability of the vegetated slope from windthrow and snow loading. Slope stability can be determined by using either limit equilibrium or

  6. Role of vegetation in a constructed wetland on nutrient-pesticide mixture toxicity to Hyalella azteca.

    Science.gov (United States)

    Lizotte, Richard E; Moore, Matthew T; Locke, Martin A; Kröger, Robert

    2011-02-01

    The toxicity of a nutrient-pesticide mixture in nonvegetated and vegetated sections of a constructed wetland (882 m² each) was assessed using Hyalella azteca 48-h aqueous whole-effluent toxicity bioassays. Both sections were amended with a mixture of sodium nitrate, triple superphosphate, diazinon, and permethrin simulating storm-event agricultural runoff. Aqueous samples were collected at inflow, middle, and outflow points within each section 5 h, 24 h, 72 h, 7 days, 14 days, and 21 days postamendment. Nutrients and pesticides were detected throughout both wetland sections with concentrations longitudinally decreasing more in vegetated than nonvegetated section within 24 h. Survival effluent dilution point estimates-NOECs, LOECs, and LC₅₀s-indicated greatest differences in toxicity between nonvegetated and vegetated sections at 5 h. Associations of nutrient and pesticide concentrations with NOECs indicated that earlier toxicity (5-72 h) was from permethrin and diazinon, whereas later toxicity (7-21 days) was primarily from diazinon. Nutrient-pesticide mixture concentration-response assessment using toxic unit models indicated that H. azteca toxicity was due primarily to the pesticides diazinon and permethrin. Results show that the effects of vegetation versus no vegetation on nutrient-pesticide mixture toxicity are not evident after 5 h and a 21-day retention time is necessary to improve H. azteca survival to ≥90% in constructed wetlands of this size. PMID:20814671

  7. National Air Toxic Assessments (NATA) Results

    Data.gov (United States)

    U.S. Environmental Protection Agency — The National Air Toxics Assessment was conducted by EPA in 2002 to assess air toxics emissions in order to identify and prioritize air toxics, emission source types...

  8. Bonneville - Hood River Vegetation Management Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    N/A

    1998-08-01

    To maintain the reliability of its electrical system, BPA, in cooperation with the U.S. Forest Service, needs to expand the range of vegetation management options used to clear unwanted vegetation on about 20 miles of BPA transmission line right-of-way between Bonneville Dam and Hood River; Oregon, within the Columbia Gorge National Scenic Area (NSA). We propose to continue controlling undesirable vegetation using a program of Integrated Vegetation Management (IVM) which includes manual, biological and chemical treatment methods. BPA has prepared an Environmental Assessment (EA) (DOE/EA-1257) evaluating the proposed project. Based on the analysis in the EA, BPA has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an Environmental Impact Statement (EIS) is not required and BPA is issuing this FONSI.

  9. Arizona Vegetation Resource Inventory (AVRI) accuracy assessment

    Science.gov (United States)

    Szajgin, John; Pettinger, L.R.; Linden, D.S.; Ohlen, D.O.

    1982-01-01

    A quantitative accuracy assessment was performed for the vegetation classification map produced as part of the Arizona Vegetation Resource Inventory (AVRI) project. This project was a cooperative effort between the Bureau of Land Management (BLM) and the Earth Resources Observation Systems (EROS) Data Center. The objective of the accuracy assessment was to estimate (with a precision of ?10 percent at the 90 percent confidence level) the comission error in each of the eight level II hierarchical vegetation cover types. A stratified two-phase (double) cluster sample was used. Phase I consisted of 160 photointerpreted plots representing clusters of Landsat pixels, and phase II consisted of ground data collection at 80 of the phase I cluster sites. Ground data were used to refine the phase I error estimates by means of a linear regression model. The classified image was stratified by assigning each 15-pixel cluster to the stratum corresponding to the dominant cover type within each cluster. This method is known as stratified plurality sampling. Overall error was estimated to be 36 percent with a standard error of 2 percent. Estimated error for individual vegetation classes ranged from a low of 10 percent ?6 percent for evergreen woodland to 81 percent ?7 percent for cropland and pasture. Total cost of the accuracy assessment was $106,950 for the one-million-hectare study area. The combination of the stratified plurality sampling (SPS) method of sample allocation with double sampling provided the desired estimates within the required precision levels. The overall accuracy results confirmed that highly accurate digital classification of vegetation is difficult to perform in semiarid environments, due largely to the sparse vegetation cover. Nevertheless, these techniques show promise for providing more accurate information than is presently available for many BLM-administered lands.

  10. Estimating vegetation dryness to optimize fire risk assessment with spot vegetation satellite data in savanna ecosystems

    Science.gov (United States)

    Verbesselt, J.; Somers, B.; Lhermitte, S.; van Aardt, J.; Jonckheere, I.; Coppin, P.

    2005-10-01

    The lack of information on vegetation dryness prior to the use of fire as a management tool often leads to a significant deterioration of the savanna ecosystem. This paper therefore evaluated the capacity of SPOT VEGETATION time-series to monitor the vegetation dryness (i.e., vegetation moisture content per vegetation amount) in order to optimize fire risk assessment in the savanna ecosystem of Kruger National Park in South Africa. The integrated Relative Vegetation Index approach (iRVI) to quantify the amount of herbaceous biomass at the end of the rain season and the Accumulated Relative Normalized Difference vegetation index decrement (ARND) related to vegetation moisture content were selected. The iRVI and ARND related to vegetation amount and moisture content, respectively, were combined in order to monitor vegetation dryness and optimize fire risk assessment in the savanna ecosystems. In situ fire activity data was used to evaluate the significance of the iRVI and ARND to monitor vegetation dryness for fire risk assessment. Results from the binary logistic regression analysis confirmed that the assessment of fire risk was optimized by integration of both the vegetation quantity (iRVI) and vegetation moisture content (ARND) as statistically significant explanatory variables. Consequently, the integrated use of both iRVI and ARND to monitor vegetation dryness provides a more suitable tool for fire management and suppression compared to other traditional satellite-based fire risk assessment methods, only related to vegetation moisture content.

  11. Direct toxicity assessment - Methods, evaluation, interpretation.

    Science.gov (United States)

    Gruiz, Katalin; Fekete-Kertész, Ildikó; Kunglné-Nagy, Zsuzsanna; Hajdu, Csilla; Feigl, Viktória; Vaszita, Emese; Molnár, Mónika

    2016-09-01

    Direct toxicity assessment (DTA) results provide the scale of the actual adverse effect of contaminated environmental samples. DTA results are used in environmental risk management of contaminated water, soil and waste, without explicitly translating the results into chemical concentration. The end points are the same as in environmental toxicology in general, i.e. inhibition rate, decrease in the growth rate or in yield and the 'no effect' or the 'lowest effect' measurement points of the sample dilution-response curve. The measurement unit cannot be a concentration, since the contaminants and their content in the sample is unknown. Thus toxicity is expressed as the sample proportion causing a certain scale of inhibition or no inhibition. Another option for characterizing the scale of toxicity of an environmental sample is equivalencing. Toxicity equivalencing represents an interpretation tool which enables toxicity of unknown mixtures of chemicals be converted into the concentration of an equivalently toxic reference substance. Toxicity equivalencing, (i.e. expressing the toxicity of unknown contaminants as the concentration of the reference) makes DTA results better understandable for non-ecotoxicologists and other professionals educated and thinking based on the chemical model. This paper describes and discusses the role, the principles, the methodology and the interpretation of direct toxicity assessment (DTA) with the aim to contribute to the understanding of the necessity to integrate DTA results into environmental management of contaminated soil and water. The paper also introduces the benefits of the toxicity equivalency method. The use of DTA is illustrated through two case studies. The first case study focuses on DTA of treated wastewater with the aim to characterize the treatment efficacy of a biological wastewater treatment plant by frequent bioassaying. The second case study applied DTA to investigate the cover layers of two bauxite residue (red mud

  12. Toxicity assessment of hydrazine fuels

    Energy Technology Data Exchange (ETDEWEB)

    Keller, W.C.

    1988-11-01

    The major health aspects of exposure to hydrazine propellants are reviewed. Toxic effects of hydrazine fuels on humans and animals as well as in vitro studies are discussed with emphasis on recent findings and USAF studies. Propellant hydrazines have been found to be genotoxic in in vitro studies and oncogenic in animal studies. Embryotoxicity has been demonstrated at very high exposures but not at occupationally encountered levels for hydrazine and unsymmetrical dimethylhydrazine. Epidemiologic evidence to support these findings is lacking; however, the results of animal and in vitro studies have resulted in lowering both the time-weighted average-threshold limit values and short-term exposure limits for these propellants.

  13. Accuracy Assessment Points for Tuzigoot National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The accuracy assessment field work was performed in May, 1997 to verify the accuracy of the vegetation communities spatial data developed by the USGS-NPS Vegetation...

  14. An integrated assessment of wild vegetable resources in Inner Mongolian Autonomous Region, China

    Directory of Open Access Journals (Sweden)

    Wujisguleng Wujisguleng

    2010-12-01

    Full Text Available Abstract Background This paper was based on ethnobotanical investigations conducted from 2004-2006 in Inner Mongolian Autonomous Region of northern China. Today, due to their nutritious and relatively pollution-free characteristics, wild vegetables are playing an increasingly important role in peoples' health and well-being. This paper aims to provide scientific clues for the selection of special and high quality wild vegetables species. Methods An ethnobotanical study, consisting of a literature survey, open-ended and semi-structured interviews, and collection and identification of voucher specimens was carried out to gather information on wild vegetables in Inner Mongolia. Next, an integrated assessment of 90 species of wild vegetables was performed using the linearity weighted integrative mathematical analysis method. Results According to an integrated assessment of 90 species of wild vegetables in Inner Mongolia, there are 5 species with the highest integrated value, 40 species of high-integrated value, 43 species of general integrated value, and 2 species of low value. The results indicate that the vast majority of wild vegetables have high value in Inner Mongolia. Conclusions Inner Mongolia is rich in wild vegetable resources. A comprehensive assessment indicates that the vast majority of wild vegetables are of high value. However, these wild vegetables are seldom collected or cultivated by local people. Most of the collected species require further research and investigation into their nutrient content, toxicity and ethnobotany to illuminate their potential as new cultivars or products.

  15. LCIA selection methods for assessing toxic releases

    DEFF Research Database (Denmark)

    Larsen, Henrik Fred; Birkved, Morten; Hauschild, Michael Zwicky

    2002-01-01

    not fulfilled) but this task is at best very time consuming and often not possible. There seems to be a need for an easy in use and less time consuming selection/screening method based on readily available substance data. The aim of such a selection method is to prioritise those emissions (chemicals) from......Characterization of toxic emissions in life cycle impact assessment (LCIA) is in many cases severely limited by the lack of characterization factors for the emissions mapped in the inventory. The number of substances assigned characterization factors for (eco)toxicity included in the dominating LCA...... the inventory that contribute significantly to the impact categories on ecotoxicity and human toxicity to focus the characterisation work. The reason why the selection methods are more important for the chemical-related impact categories than for other impact categories is the extremely high number...

  16. Subacute toxicity assessment of annatto in rat.

    Science.gov (United States)

    Bautista, A R P L; Moreira, E L T; Batista, M S; Miranda, M S; Gomes, I C S

    2004-04-01

    Increased human use of annatto (Bixa orellana L), a red yellow food colorant, demands generation of toxicity data. The toxic effects of annatto powder (bixin 27%) have been assessed following administration of a subacute regimen (4 weeks, 20 doses) in Wistar male and female rats. A full study with three dose levels was considered unnecessary since no sign of toxicity had been noted in a preliminary experiment with 1000 mg/kg body weight/day as was recommended by the OECD guideline. In this study, annatto administered by gavage at a dose level of 2000 mg/kg/day decreased male body weight gain, but had no effect on either food intake or food conversion efficiency. Haematological and plasma biochemical examination as well necropsy performed at the end of administration (29th day) and observation (43rd day) periods revealed no alterations related with annatto administration. Kidney apoptosis occurred in 20% treated female rats in restricted areas without proliferation or tubular segments modification. The precise nature of apoptosis was not investigated in the present study. These findings suggest that annatto was no toxic to the rat. PMID:15019187

  17. Long-term toxicity assessment of soils in a recovered area affected by a mining spill.

    Science.gov (United States)

    Romero-Freire, A; García Fernández, I; Simón Torres, M; Martínez Garzón, F J; Martín Peinado, F J

    2016-01-01

    Residual pollution in the Guadiamar Green Corridor still remains after Aználcollar mine spill in 1998. The polluted areas are identified by the absence of vegetation, soil acidic pH and high concentrations of As, Pb, Zn and Cu. Soil toxicity was assessed by lettuce root elongation and induced soil respiration bioassays. In bare soils, total As and Pb concentrations and water-extractable levels for As, Zn and Cu exceeded the toxicity guidelines. Pollutants responsible for toxicity were different depending on the tested organism, with arsenic being most toxic for lettuce and the metal mixture to soil respiration. Soil properties, such as pH or organic carbon content, are key factors to control metal availability and toxicity in the area. According to our results, there is a risk of pollution to living organisms and the soil quality criteria established in the area should be revised to reduce the risk of toxicity.

  18. Accuracy Assessment Points for Dinosaur National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This point file displays the 1543 accuracy assessment (AA) points visited in the summer of 2005 as part of the vegetation mapping project. The points were randomly...

  19. Accuracy Assessment Points for Colorado National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This point file displays the 500 accuracy assessment (AA) points visited in July and August of 2004 as part of the vegetation mapping project. Five hundred and one...

  20. Accuracy Assessment Points for Badlands National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the accuracy assessment data associated with the vegetation land cover and land use geospatial database for Badlands National Park and...

  1. Accuracy Assessment Points for Wupatki National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This spatial dataset in ESRI Coverage format maps accuracy assessment point locations for the vegetation map at Wupatki National Monument and in the surrounding...

  2. 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

  3. Vegetation Health and Productivity Indicators for Sustained National Climate Assessments

    Science.gov (United States)

    Jones, M. O.; Running, S. W.

    2014-12-01

    The National Climate Assessment process is developing a system of physical, ecological, and societal indicators that communicate key aspects of the physical climate, climate impacts, vulnerabilities, and preparedness for the purpose of informing both decision makers and the public. Implementing a 14 year record of Gross and Net Primary Productivity (GPP/NPP) derived from the NASA EOS MODIS satellite sensor we demonstrate how these products can serve as Ecosystem Productivity and Vegetation Health National Climate Indicators for implementation in sustained National Climate Assessments. The NPP product combines MODIS vegetation data with daily global meteorology to calculate annual growth of all plant material at 1 sq. km resolution. NPP anomalies identify regions with above or below average plant growth that may result from climate fluctuations and can inform carbon source/sink dynamics, agricultural and forestry yield measures, and response to wildfire or drought conditions. The GPP product provides a high temporal resolution (8-day) metric of vegetation growth which can be used to monitor short-term vegetation response to extreme events and implemented to derive vegetation phenology metrics; growing season start, end, and length, which can elucidate land cover and regionally specific vegetation responses to a changing climate. The high spatial resolution GPP and NPP indicators can also inform and clarify responses seen from other proposed Pilot Indicators such as forest growth/productivity, land cover, crop production, and phenology. The GPP and NPP data are in continuous production and will be sustained into the future with the next generation satellite missions. The long-term Ecosystem Productivity and Vegetation Health Indicators are ideal for use in sustained National Climate Assessments, providing regionally specific responses to a changing climate and complete coverage at the national scale.

  4. Biodegradation and toxicity of vegetable oils in contaminated aquatic environments: Effect of antioxidants and oil composition.

    Science.gov (United States)

    Salam, Darine A; Suidan, Makram T; Venosa, Albert D

    2016-03-15

    Antioxidants may affect the oxidative rate of vegetable oils determining their fate and impact in contaminated aquatic media. In previous studies, we demonstrated the effectiveness of butylated hydroxytoluene (BHT), one of the most used antioxidants in edible oils, in enhancing the biodegradation of glyceryl trilinoleate, a pure triacylglycerol of cis,cis-9,12-octadecadienoic acid (C18:2 delta), through retarding its oxidative polymerization relatively to the oil with no added antioxidant. In this study, the effect of BHT on the biodegradation and toxicity of purified canola oil, a mixed-acid triacylglycerol with high C18:1 content, was investigated in respirometric microcosms and by use of the Microtox® assay. Investigations were carried out in the absence and presence (200 mg kg(-1)) of the antioxidant, and at an oil loading of 0.31 L m(-2) (333 gal acre(-1)). Substantial oil mineralization was achieved after 16 weeks of incubation (>77%) and was not significantly different (p>0.05) between the two BHT treatments, demonstrating an important role of the oil fatty acid composition in determining the potency of antioxidants and, consequently, the fate of spilled vegetable oils. Furthermore, for both treatments, toxicity was measured at early stages of the experiments and disappeared at a later stage of incubation. The observed transient toxicity was associated with the combined effect of toxic biodegradation intermediates and autoxidation products. These results were supported by the gradual disappearance of BHT in the microcosms initially supplemented with the antioxidant, reaching negligible amounts after only 2 weeks of incubation. PMID:26780134

  5. CHATTANOOGA AIR TOXICS (CATS) MONITORING RISK ASSESSMENT

    Science.gov (United States)

    The Chattanooga-Hamilton County Air Pollution Control Bureau (CHCAPCB), the United States Environmental Protection Agency Region 4 (Region 4), and other stakeholders, in a cooperative effort, conducted an air toxics study in the Chattanooga area (city population approximately 285...

  6. 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.

  7. Assessing sediment contamination using six toxicity assays

    Directory of Open Access Journals (Sweden)

    Allen G. BURTON Jr.

    2001-08-01

    Full Text Available An evaluation of sediment toxicity at Lake Orta, Italy was conducted to compare a toxicity test battery of 6 assays and to evaluate the extent of sediment contamination at various sediment depths. Lake Orta received excessive loadings of copper and ammonia during the 1900’s until a large remediation effort was conducted in 1989-90 using lime addition. Since that time, the lake has shown signs of a steady recovery of biological communities. The study results showed acute toxicity still exists in sediments at a depth of 5 cm and greater. Assays that detected the highest levels of toxicity were two whole sediment exposures (7 d using Hyalella azteca and Ceriodaphnia dubia. The MicrotoxR assay using pore water was the third most sensitive assay. The Thamnotox, Rototox, Microtox solid phase, and Seed Germination-Root Elongation (pore and solid phase assays showed occasional to no toxicity. Based on similarity of responses and assay sensitivity, the two most useful assays were the C. dubia (or H. azteca and Microtox pore water. These assays were effective at describing sediment toxicity in a weight-of-evidence approach.

  8. Assessing global vegetation activity using spatio-temporal Bayesian modelling

    Science.gov (United States)

    Mulder, Vera L.; van Eck, Christel M.; Friedlingstein, Pierre; Regnier, Pierre A. G.

    2016-04-01

    This work demonstrates the potential of modelling vegetation activity using a hierarchical Bayesian spatio-temporal model. This approach allows modelling changes in vegetation and climate simultaneous in space and time. Changes of vegetation activity such as phenology are modelled as a dynamic process depending on climate variability in both space and time. Additionally, differences in observed vegetation status can be contributed to other abiotic ecosystem properties, e.g. soil and terrain properties. Although these properties do not change in time, they do change in space and may provide valuable information in addition to the climate dynamics. The spatio-temporal Bayesian models were calibrated at a regional scale because the local trends in space and time can be better captured by the model. The regional subsets were defined according to the SREX segmentation, as defined by the IPCC. Each region is considered being relatively homogeneous in terms of large-scale climate and biomes, still capturing small-scale (grid-cell level) variability. Modelling within these regions is hence expected to be less uncertain due to the absence of these large-scale patterns, compared to a global approach. This overall modelling approach allows the comparison of model behavior for the different regions and may provide insights on the main dynamic processes driving the interaction between vegetation and climate within different regions. The data employed in this study encompasses the global datasets for soil properties (SoilGrids), terrain properties (Global Relief Model based on SRTM DEM and ETOPO), monthly time series of satellite-derived vegetation indices (GIMMS NDVI3g) and climate variables (Princeton Meteorological Forcing Dataset). The findings proved the potential of a spatio-temporal Bayesian modelling approach for assessing vegetation dynamics, at a regional scale. The observed interrelationships of the employed data and the different spatial and temporal trends support

  9. Ecotoxicogenomic assessment of diclofenac toxicity in soil

    International Nuclear Information System (INIS)

    Diclofenac is widely used as nonsteroidal anti-inflammatory drug leaving residues in the environment. To investigate effects on terrestrial ecosystems, we measured dissipation rate in soil and investigated ecotoxicological and transcriptome-wide responses in Folsomia candida. Exposure for 4 weeks to diclofenac reduced both survival and reproduction of F. candida in a dose-dependent manner. At concentrations ≥200 mg/kg soil diclofenac remained stable in the soil during a 21-day incubation period. Microarrays examined transcriptional changes at low and high diclofenac exposure concentrations. The results indicated that development and growth were severely hampered and immunity-related genes, mainly directed against bacteria and fungi, were significantly up-regulated. Furthermore, neural metabolic processes were significantly affected only at the high concentration. We conclude that diclofenac is toxic to non-target soil invertebrates, although its mode of action is different from the mammalian toxicity. The genetic markers proposed in this study may be promising early markers for diclofenac ecotoxicity. - Highlights: • Diclofenac is toxic to the non-target soil invertebrate Folsomia candida. • Diclofenac mainly caused mortality and thus only indirectly affected reproduction. • Diclofenac mode of action in F. candida was checked with gene expression profiling. • Diclofenac significantly affected development, growth and immune related processes. • Diclofenac nervous system activity in F. candida was different from that in mammals. - Diclofenac is toxic to non-target soil invertebrates with a mode of action clearly different from mammalian toxicity

  10. Vegetation recovery assessment following large wildfires in the Mediterranean Basin

    Science.gov (United States)

    Bastos, A.; Gouveia, C. M.; Trigo, R. M.; DaCamara, C. C.

    2012-04-01

    Mediterranean ecosystems have evolved along with fire, adapting to quick recovering following wildfire events. However, vegetation species respond differently to the changes in fire regimes that have been observed in the past decades in the Mediterranean. These changes, which occurred mainly due to socio-economic and climatic changes, led to dramatic modifications of landscape composition and structure (Malkinson et al., 2011). Post-fire vegetation recovery depends on environmental factors such as landscape features and climatic variables and on specific plant traits; however it also depends on the differentiated response of each species to the characteristics of fire regimes, such as recurrence, severity and extent. The complexity of the interactions between these factors emphasizes the importance of assessing quantitatively post-fire recovery as well as the role of driving factors of regeneration over different regions in the Mediterranean. In 2006, Spain experienced the fire season with larger fires, restricted to a relatively small region of the province of Galicia, that represents more than 60% of total burned area of this fire season (92000ha out of 148827 ha). The 2007 fire season in Greece was remarkably severe, registering the highest value of burnt area (225734 ha) since 1980. Finally, in 2010 a very large wildfire of about 5000 ha occurred in Mount Carmel, Israel, with major social and environmental impacts. The work relies on monthly NDVI data from SPOT/VEGETATION at 1km spatial resolution over the period from September 1998 - August 2011 for Spain, Greece and Israel. Here we have applied the same sequential methodology developed at our laboratory, starting by the identification of very large burnt scars by means of a spatial cluster analysis followed by the application of the monoparametric model (Gouveia et al., 2010; Bastos et al., 2011) in order to study post-fire vegetation dynamics. Post-fire recovery times were estimated for burnt scars from each

  11. Repellency, toxicity, and oviposition inhibition of vegetable extracts against greenhouse whitefly Trialeurodes vaporariorum (Westwood (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Edgar Eduardo Mendoza-Garcia

    2014-03-01

    Full Text Available In a search for sustainable options of greenhouse whitefly Trialeurodes vaporariorum (Westwood management, the toxic and/or repellent potential of water, ethanolic, and acetonic extracts of Ambrosia artemisiifolia L. (Asteraceae, Comocladia engleriana Loes (Anacardiaceae, Piper auritum Kunth (Piperaceae, Raphanus raphanistrum L. (Brassicaceae, and Taraxacum officinale F.H. Wigg. aggr.* (Asteraceae were evaluated. Repellency was assessed by the cylinder method (olfactometer, while toxicity and oviposition inhibition were assessed by the leaf immersion method. Acetonic extracts did not cause any repellent or insecticidal effect. In contrast, 200 mg mL-1 water and ethanolic extracts of R. raphanistrum and ethanolic extract of A. artemisiifolia had the highest repellent activity (76%, 72%, and 69%, respectively although their activity decreased gradually over time. Ethanolic extracts of P. auritum (66% and R. raphanistrum (56% at 200 mg mL¹ were highlighted as being toxic, while the most effective in inhibiting oviposition were water extracts of R. raphanistrum (76.1% and P. auritum (72.0% and ethanolic extract of P. auritum (69.5%; however, concentrations lower than 60 mg mL-1 caused oviposition stimulation. Our results suggest that water and ethanolic extracts of R. raphanistrum and P. auritum represent a useful tool in integrated whitefly management.

  12. Accumulation of Heavy Metals in Vegetable Species Planted in Contaminated Soils and the Health Risk Assessment

    Science.gov (United States)

    Zhou, Hang; Yang, Wen-Tao; Zhou, Xin; Liu, Li; Gu, Jiao-Feng; Wang, Wen-Lei; Zou, Jia-Ling; Tian, Tao; Peng, Pei-Qin; Liao, Bo-Han

    2016-01-01

    The objectives of the present study were to investigate heavy metal accumulation in 22 vegetable species and to assess the human health risks of vegetable consumption. Six vegetable types were cultivated on farmland contaminated with heavy metals (Pb, Cd, Cu, Zn, and As). The target hazard quotient (THQ) method was used to assess the human health risks posed by heavy metals through vegetable consumption. Clear differences were found in the concentrations of heavy metals in edible parts of the different vegetables. The concentrations of heavy metals decreased in the sequence as leafy vegetables > stalk vegetables/root vegetables/solanaceous vegetables > legume vegetables/melon vegetables. The ability of leafy vegetables to uptake and accumulate heavy metals was the highest, and that of melon vegetables was the lowest. This indicated that the low accumulators (melon vegetables) were suitable for being planted on contaminated soil, while the high accumulators (leafy vegetables) were unsuitable. In Shizhuyuan area, China, the total THQ values of adults and children through consumption of vegetables were 4.12 and 5.41, respectively, suggesting that the residents may be facing health risks due to vegetable consumption, and that children were vulnerable to the adverse effects of heavy metal ingestion. PMID:26959043

  13. Accumulation of Heavy Metals in Vegetable Species Planted in Contaminated Soils and the Health Risk Assessment.

    Science.gov (United States)

    Zhou, Hang; Yang, Wen-Tao; Zhou, Xin; Liu, Li; Gu, Jiao-Feng; Wang, Wen-Lei; Zou, Jia-Ling; Tian, Tao; Peng, Pei-Qin; Liao, Bo-Han

    2016-03-04

    The objectives of the present study were to investigate heavy metal accumulation in 22 vegetable species and to assess the human health risks of vegetable consumption. Six vegetable types were cultivated on farmland contaminated with heavy metals (Pb, Cd, Cu, Zn, and As). The target hazard quotient (THQ) method was used to assess the human health risks posed by heavy metals through vegetable consumption. Clear differences were found in the concentrations of heavy metals in edible parts of the different vegetables. The concentrations of heavy metals decreased in the sequence as leafy vegetables > stalk vegetables/root vegetables/solanaceous vegetables > legume vegetables/melon vegetables. The ability of leafy vegetables to uptake and accumulate heavy metals was the highest, and that of melon vegetables was the lowest. This indicated that the low accumulators (melon vegetables) were suitable for being planted on contaminated soil, while the high accumulators (leafy vegetables) were unsuitable. In Shizhuyuan area, China, the total THQ values of adults and children through consumption of vegetables were 4.12 and 5.41, respectively, suggesting that the residents may be facing health risks due to vegetable consumption, and that children were vulnerable to the adverse effects of heavy metal ingestion.

  14. Polycyclic aromatic hydrocarbons in Dalian soils: distribution and toxicity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.; Chen, J.W.; Yang, P.; Qiao, X.L.; Tian, F. [Dalian University of Technology, Dalian (China). Dept. of Environmental Science & Technology

    2007-07-01

    Concentrations of 15 polycyclic aromatic hydrocarbons (PAHs) were measured in surface soils collected from Dalian, China, for examination of distributions and composition profiles and their potential toxicity. The sum of 15 PAHs ({Sigma} PAHs) ranged from 190 to 8595 ng g{sup -1} dry weight, and showed an apparent urban-suburban-rural gradient in both {Sigma} PAHs and composition profiles. Using hierarchical cluster analysis (HCA), the sampling sites were grouped into four clusters corresponding to traffic area, park/residential area, suburban and rural areas. The ratios of naphthalene (Nap) and fluorene (Fl) versus fluoranthene (Flu), pyrene (Pyr) and indeno(1,2,3-cd) pyrene (InP) in the four clusters provided evidence of local distillation. The diagnostic ratios indicated the prevalent PAH sources were petroleum combustion and coal combustion in Dalian, and a cross plot of diagnostic ratios distinguished the urban samples from suburban and rural ones. Toxic potency assessment of soil PAHs presented a good relationship with benzo(a) pyrene (BaP) levels, toxic equivalent concentrations based on BaP (TEQ(BaP)) and dioxin-like toxic equivalent concentrations (TEQ(TCDD)). The study highlights that BaP is a good indicator for assessing the potential toxicity of PAHs, and presents a promising toxicity assessment method for soil PAHs.

  15. Polycyclic aromatic hydrocarbons in Dalian soils: distribution and toxicity assessment.

    Science.gov (United States)

    Wang, Zhen; Chen, Jingwen; Yang, Ping; Qiao, Xianliang; Tian, Fulin

    2007-02-01

    Concentrations of 15 polycyclic aromatic hydrocarbons (PAHs) were measured in surface soils collected from Dalian, China, for examination of distributions and composition profiles and their potential toxicity. The sum of 15 PAHs (SigmaPAHs) ranged from 190 to 8595 ng g(-1) dry weight, and showed an apparent urban-suburban-rural gradient in both SigmaPAHs and composition profiles. Using hierarchical cluster analysis (HCA), the sampling sites were grouped into four clusters corresponding to traffic area, park/residential area, suburban and rural areas. The ratios of naphthalene (Nap) and fluorene (Fl) versus fluoranthene (Flu), pyrene (Pyr) and indeno(1,2,3-cd)pyrene (InP) in the four clusters provided evidence of local distillation. The diagnostic ratios indicated the prevalent PAH sources were petroleum combustion and coal combustion in Dalian, and a cross plot of diagnostic ratios distinguished the urban samples from suburban and rural ones. Toxic potency assessment of soil PAHs presented a good relationship with benzo(a)pyrene (BaP) levels, toxic equivalent concentrations based on BaP (TEQ(BaP)) and dioxin-like toxic equivalent concentrations (TEQ(TCDD)). The study highlights that BaP is a good indicator for assessing the potential toxicity of PAHs, and presents a promising toxicity assessment method for soil PAHs. PMID:17285163

  16. Use of toxicity identification evaluations to determine the pesticide mitigation effectiveness of on-farm vegetated treatment systems

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, John [Department of Environmental Toxicology, University of California, Davis, CA (United States); Department of Environmental Studies, University of California, Santa Cruz, CA (United States); Marine Pollution Studies Laboratory, Granite Canyon, 34500 Highway 1, Monterey, CA 93940 (United States)], E-mail: jwhunt@ucdavis.edu; Anderson, Brian [Department of Environmental Toxicology, University of California, Davis, CA (United States); Marine Pollution Studies Laboratory, Granite Canyon, 34500 Highway 1, Monterey, CA 93940 (United States)], E-mail: anderson@ucdavis.edu; Phillips, Bryn [Department of Environmental Toxicology, University of California, Davis, CA (United States); Marine Pollution Studies Laboratory, Granite Canyon, 34500 Highway 1, Monterey, CA 93940 (United States)], E-mail: bmphillips@ucdavis.edu; Tjeerdema, Ron [Department of Environmental Toxicology, University of California, Davis, CA (United States); Marine Pollution Studies Laboratory, Granite Canyon, 34500 Highway 1, Monterey, CA 93940 (United States)], E-mail: rstjeerdema@ucdavis.edu; Largay, Bryan [Largay Hydrologic Sciences, LLC, 160 Farmer Street Felton, CA 95018-9416 (United States)], E-mail: bryan.largay@sbcglobal.net; Beretti, Melanie [Resources Conservation District of Monterey County, 744-A La Guardia Street, Salinas, CA 93905 (United States)], E-mail: beretti.melanie@rcdmonterey.org; Bern, Amanda [California Regional Water Quality Control Board, Central Coast Region, 895 Aerovista Place, Suite 101, San Luis Obispo, CA 93401 (United States)], E-mail: abern@waterboards.ca.gov

    2008-11-15

    Evidence of ecological impacts from pesticide runoff has prompted installation of vegetated treatment systems (VTS) along the central coast of California, USA. During five surveys of two on-farm VTS ponds, 88% of inlet and outlet water samples were toxic to Ceriodaphnia dubia. Toxicity identification evaluations (TIEs) indicated water toxicity was caused by diazinon at VTS-1, and chlorpyrifos at VTS-2. Diazinon levels in VTS-1 were variable, but high pulse inflow concentrations were reduced through dilution. At VTS-2, chlorpyrifos concentrations averaged 52% lower at the VTS outlet than at the inlet. Water concentrations of most other pesticides averaged 20-90% lower at VTS outlets. All VTS sediment samples were toxic to amphipods (Hyalella azteca). Sediment TIEs indicated toxicity was caused by cypermethrin and lambda-cyhalothrin at VTS-1, and chlorpyrifos and permethrin at VTS-2. As with water, sediment concentrations were lower at VTS outlets, indicating substantial reductions in farm runoff pesticide concentrations. - Toxicity identification evaluations identified key pesticides in agricultural runoff, and their concentrations were reduced by farmer-installed vegetated treatment systems.

  17. Human health risk assessment: Heavy metal contamination of vegetables in Bahawalpur, Pakistan

    OpenAIRE

    Iqbal, Hafiza Hira; Taseer, Raffia; Anwar, Seham; Mumtaz, Mehvish; Qadir, Abdul; Shahid, Naeem

    2016-01-01

    Dietary exposure of toxic metals is of vital concern for human health through vegetable consumption, especially in developing countries. Aim of the current study was to determine the health risk associated with vegetables contamination by heavy metals being irrigated with sewage and turbine water. The water sources, soils and vegetables were analyzed for selected metals viz: Pb, Cd, Cr and Ni. Heavy metals in water samples are found to be lower than the international norms except Cd in sewage...

  18. Accuracy Assessment Points for Wind Cave National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The accuracy assessment field work was performed to verify the accuracy of the vegetation communities spatial data developed by the USGS-NPS Vegetation Mapping...

  19. Rapid bioassay-guided screening of toxic substances in vegetable oils that shorten the life of SHRSP rats

    Directory of Open Access Journals (Sweden)

    Lewandowski Paul

    2010-02-01

    Full Text Available Abstract It has been consistently reported that vegetable oils including canola oil have a life shortening effect in Stroke-Prone Spontaneously Hypertensive Rats (SHRSP and this toxic effect is not due to the fatty acid composition of the oil. Although it is possible that the phytosterol content or type of phytosterol present in vegetable oils may play some role in the life shortening effect observed in SHRSP rats this is still not completely resolved. Furthermore supercritical CO2 fractionation of canola oil with subsequent testing in SHRSP rats identified safe and toxic fractions however, the compounds responsible for life shortening effect were not characterised. The conventional approach to screen toxic substances in oils using rats takes more than six months and involves large number of animals. In this article we describe how rapid bioassay-guided screening could be used to identify toxic substances derived from vegetable oils and/or processed foods fortified with vegetable oils. The technique incorporates sequential fractionation of oils/processed foods and subsequent treatment of human cell lines that can be used in place of animal studies to determine cytotoxicity of the fractions with structural elucidation of compounds of interest determined via HPLC-MS and GC-MS. The rapid bioassay-guided screening proposed would require two weeks to test multiple fractions from oils, compared with six months if animal experiments were used to screen toxic effects. Fractionation of oil before bio-assay enhances the effectiveness of the detection of active compounds as fractionation increases the relative concentration of minor components.

  20. Accumulation of Heavy Metals in Vegetable Species Planted in Contaminated Soils and the Health Risk Assessment

    OpenAIRE

    Hang Zhou; Wen-Tao Yang; Xin Zhou; Li Liu; Jiao-Feng Gu; Wen-Lei Wang; Jia-Ling Zou; Tao Tian; Pei-Qin Peng; Bo-Han Liao

    2016-01-01

    The objectives of the present study were to investigate heavy metal accumulation in 22 vegetable species and to assess the human health risks of vegetable consumption. Six vegetable types were cultivated on farmland contaminated with heavy metals (Pb, Cd, Cu, Zn, and As). The target hazard quotient (THQ) method was used to assess the human health risks posed by heavy metals through vegetable consumption. Clear differences were found in the concentrations of heavy metals in edible parts of the...

  1. Toxicity assessment using different bioassays and microbial biosensors.

    Science.gov (United States)

    Hassan, Sedky H A; Van Ginkel, Steven W; Hussein, Mohamed A M; Abskharon, Romany; Oh, Sang-Eun

    2016-01-01

    Toxicity assessment of water streams, wastewater, and contaminated sediments, is a very important part of environmental pollution monitoring. Evaluation of biological effects using a rapid, sensitive and cost effective method can indicate specific information on ecotoxicity assessment. Recently, different biological assays for toxicity assessment based on higher and lower organisms such as fish, invertebrates, plants and algal cells, and microbial bioassays have been used. This review focuses on microbial biosensors as an analytical device for environmental, food, and biomedical applications. Different techniques which are commonly used in microbial biosensing include amperometry, potentiometry, conductometry, voltammetry, microbial fuel cells, fluorescence, bioluminescence, and colorimetry. Examples of the use of different microbial biosensors in assessing a variety of environments are summarized. PMID:27071051

  2. The assessment of neurobehavioral toxicity: SGOMSEC joint report.

    OpenAIRE

    Fiedler, N; Feldman, R G; Jacobson, J.; Rahill, A; Wetherell, A

    1996-01-01

    Exposure to neurobehavioral toxicants is a problem of international scope. Although many different procedures are available for the assessment of human behavioral function, performance tests are displacing traditional diagnostic tests for ascertaining the consequences of exposure to neurotoxic chemicals. Performance testing includes variables such as attention and concentration, sensory function, motor control, spatial relations, visuomotor coordination, memory, and affect. Special tests have...

  3. Toxicological Considerations, Toxicity Assessment, and Risk Management of Inhaled Nanoparticles

    Science.gov (United States)

    Bakand, Shahnaz; Hayes, Amanda

    2016-01-01

    Novel engineered nanoparticles (NPs), nanomaterial (NM) products and composites, are continually emerging worldwide. Many potential benefits are expected from their commercial applications; however, these benefits should always be balanced against risks. Potential toxic effects of NM exposure have been highlighted, but, as there is a lack of understanding about potential interactions of nanomaterials (NMs) with biological systems, these side effects are often ignored. NPs are able to translocate to the bloodstream, cross body membrane barriers effectively, and affect organs and tissues at cellular and molecular levels. NPs may pass the blood–brain barrier (BBB) and gain access to the brain. The interactions of NPs with biological milieu and resulted toxic effects are significantly associated with their small size distribution, large surface area to mass ratio (SA/MR), and surface characteristics. NMs are able to cross tissue and cell membranes, enter into cellular compartments, and cause cellular injury as well as toxicity. The extremely large SA/MR of NPs is also available to undergo reactions. An increased surface area of the identical chemical will increase surface reactivity, adsorption properties, and potential toxicity. This review explores biological pathways of NPs, their toxic potential, and underlying mechanisms responsible for such toxic effects. The necessity of toxicological risk assessment to human health should be emphasised as an integral part of NM design and manufacture. PMID:27314324

  4. Toxicological Considerations, Toxicity Assessment, and Risk Management of Inhaled Nanoparticles.

    Science.gov (United States)

    Bakand, Shahnaz; Hayes, Amanda

    2016-01-01

    Novel engineered nanoparticles (NPs), nanomaterial (NM) products and composites, are continually emerging worldwide. Many potential benefits are expected from their commercial applications; however, these benefits should always be balanced against risks. Potential toxic effects of NM exposure have been highlighted, but, as there is a lack of understanding about potential interactions of nanomaterials (NMs) with biological systems, these side effects are often ignored. NPs are able to translocate to the bloodstream, cross body membrane barriers effectively, and affect organs and tissues at cellular and molecular levels. NPs may pass the blood-brain barrier (BBB) and gain access to the brain. The interactions of NPs with biological milieu and resulted toxic effects are significantly associated with their small size distribution, large surface area to mass ratio (SA/MR), and surface characteristics. NMs are able to cross tissue and cell membranes, enter into cellular compartments, and cause cellular injury as well as toxicity. The extremely large SA/MR of NPs is also available to undergo reactions. An increased surface area of the identical chemical will increase surface reactivity, adsorption properties, and potential toxicity. This review explores biological pathways of NPs, their toxic potential, and underlying mechanisms responsible for such toxic effects. The necessity of toxicological risk assessment to human health should be emphasised as an integral part of NM design and manufacture. PMID:27314324

  5. Accuracy Assessment Points for Acadia National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The U.S. Geological Survey Upper Midwest Environmental Sciences Center (UMESC) has produced a vegetation spatial database coverage (vegetation map) for the Acadia...

  6. Vegetable and synthetic tannins induce hormesis/toxicity in sea urchin early development and in algal growth

    International Nuclear Information System (INIS)

    Mimosa tannin and phenol-based synthetic tannin (syntan) were tested for toxicity to sea urchin (Paracentrotus lividus and Sphaerechinus granularis) early development and to marine algal growth (Dunaliella tertiolecta). Sea urchin embryogenesis was affected by vegetable tannin and syntan water extracts (VTWE and STWE) at levels ≥1 mg/L. Developmental defects were significantly decreased at VTWE and STWE levels of 0.1 and 0.3 mg/L when control cultures displayed suboptimal quality, i.e. <70% 'viable' (normal or retarded) larvae. Fertilization success of sea urchin sperm was increased up to 0.3 mg/L STWE or VTWE, then was inhibited by increasing tannin levels (1-30 mg/L). Offspring abnormalities, following sperm exposure to VTWE or STWE, showed the same shift from hormesis to toxicity. Cell growth bioassays in D. tertiolecta exposed to VTWE or STWE (0.1-30 mg/L) showed non-linear concentration-related toxicity. Novel criteria are suggested in defining control quality that should reveal hormetic effects. - Vegetable tannin and synthetic tannins were moderately toxic or displayed hormetic effects in sea urchins and in algae. Re-defining control quality is needed for evaluating hormetic effects

  7. Vegetable and synthetic tannins induce hormesis/toxicity in sea urchin early development and in algal growth

    Energy Technology Data Exchange (ETDEWEB)

    De Nicola, Elena [Italian National Cancer Institute, G. Pascale Foundation, via M. Semmola, I-80131 Naples (Italy); Meric, Suereyya [Department of Civil Engineering, Salerno University, I-84084 Fisciano (Italy); Gallo, Marialuisa [Campania Regional Agency for Environmental Protection (ARPAC), I-80143 Naples (Italy); Iaccarino, Mario [Italian National Cancer Institute, G. Pascale Foundation, via M. Semmola, I-80131 Naples (Italy); Della Rocca, Claudio [Department of Civil Engineering, Salerno University, I-84084 Fisciano (Italy); Lofrano, Giusy [Department of Civil Engineering, Salerno University, I-84084 Fisciano (Italy); Russo, Teresa [Campania Regional Agency for Environmental Protection (ARPAC), I-80143 Naples (Italy); Pagano, Giovanni [Italian National Cancer Institute, G. Pascale Foundation, via M. Semmola, I-80131 Naples (Italy)]. E-mail: gbpagano@tin.it

    2007-03-15

    Mimosa tannin and phenol-based synthetic tannin (syntan) were tested for toxicity to sea urchin (Paracentrotus lividus and Sphaerechinus granularis) early development and to marine algal growth (Dunaliella tertiolecta). Sea urchin embryogenesis was affected by vegetable tannin and syntan water extracts (VTWE and STWE) at levels {>=}1 mg/L. Developmental defects were significantly decreased at VTWE and STWE levels of 0.1 and 0.3 mg/L when control cultures displayed suboptimal quality, i.e. <70% 'viable' (normal or retarded) larvae. Fertilization success of sea urchin sperm was increased up to 0.3 mg/L STWE or VTWE, then was inhibited by increasing tannin levels (1-30 mg/L). Offspring abnormalities, following sperm exposure to VTWE or STWE, showed the same shift from hormesis to toxicity. Cell growth bioassays in D. tertiolecta exposed to VTWE or STWE (0.1-30 mg/L) showed non-linear concentration-related toxicity. Novel criteria are suggested in defining control quality that should reveal hormetic effects. - Vegetable tannin and synthetic tannins were moderately toxic or displayed hormetic effects in sea urchins and in algae. Re-defining control quality is needed for evaluating hormetic effects.

  8. Accuracy Assessment Points for Friendship Hill National Historic Site Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Location of thematic accuracy assessment sampling points used in the vegetation classification and mapping of Friendship Hill National Historic Site.

  9. Photoenhanced toxicity of oil in spill response and impact assessment

    Energy Technology Data Exchange (ETDEWEB)

    Barron, M.G. [P.E.A.K. Research, Longmont, CO (United States)

    2003-07-01

    Photoenhanced toxicity is described as the increase in chemical toxicity to aquatic organisms that have also been exposed to light sources containing ultraviolet radiation (UV). When tested under natural sunlight or laboratory sources of UV, fresh and weathered crude oils and spill products exhibit phototoxicity. These same products do not exhibit phototoxicity under standard testing with fluorescent lighting. Spill water from the North Cape fuel oil spill and Alaska North Slope crude oil dispersed with the chemical agent Corexit 9527 exhibited phototoxicity when tested under UV light sources. The greatest potential hazard of photoenhanced toxicity is expected to be felt by embryo and larval stages of aquatic organisms inhabiting the photic zone of the water column and intertidal areas because they are relatively translucent to UV. The author suggested that assessment of oil spill impacts should take into consideration photoenhanced toxicity since it may have an impact on the estimates of spatial and temporal extent of injury to aquatic organisms. In addition, the degree of photoenhanced toxicity may be influenced by the choice of remedial action and oil removal operations. 22 refs., 1 tab., 4 figs.

  10. Photoenhanced toxicity of oil in spill response and impact assessment

    International Nuclear Information System (INIS)

    Photoenhanced toxicity is described as the increase in chemical toxicity to aquatic organisms that have also been exposed to light sources containing ultraviolet radiation (UV). When tested under natural sunlight or laboratory sources of UV, fresh and weathered crude oils and spill products exhibit phototoxicity. These same products do not exhibit phototoxicity under standard testing with fluorescent lighting. Spill water from the North Cape fuel oil spill and Alaska North Slope crude oil dispersed with the chemical agent Corexit 9527 exhibited phototoxicity when tested under UV light sources. The greatest potential hazard of photoenhanced toxicity is expected to be felt by embryo and larval stages of aquatic organisms inhabiting the photic zone of the water column and intertidal areas because they are relatively translucent to UV. The author suggested that assessment of oil spill impacts should take into consideration photoenhanced toxicity since it may have an impact on the estimates of spatial and temporal extent of injury to aquatic organisms. In addition, the degree of photoenhanced toxicity may be influenced by the choice of remedial action and oil removal operations. 22 refs., 1 tab., 4 figs

  11. Aquatic vegetation indices assessment through radiative transfer modeling and linear mixture simulation

    Science.gov (United States)

    Villa, Paolo; Mousivand, Alijafar; Bresciani, Mariano

    2014-08-01

    Although spectral vegetation indices (VIs) have been widely used for remote sensing of vegetation in general, such indices have been traditionally targeted at terrestrial, more than aquatic, vegetation. This study introduces two new VIs specifically targeted at aquatic vegetation: NDAVI and WAVI and assesses their performance in capturing information about aquatic vegetation features by comparison with pre-existing indices: NDVI, SAVI and EVI. The assessment methodology is based on: (i) theoretical radiative transfer modeling of vegetation canopy-backgrounds coupling, and (ii) spectral linear mixture simulation based on real-case endmembers. Two study areas, Lake Garda and Lakes of Mantua, in Northern Italy, and a multisensor dataset have been exploited for our study. Our results demonstrate the advantages of the new indices. In particular, NDAVI and WAVI sensitivity scores to LAI and LIDF parameters were generally higher than pre-existing indices' ones. Radiative transfer modeling and real-case based linear mixture simulation showed a general positive, non-linear correlation of vegetation indices with increasing LAI and vegetation fractional cover (FC), more marked for NDVI and NDAVI. Moreover, NDAVI and WAVI show enhanced capabilities in separating terrestrial from aquatic vegetation response, compared to pre-existing indices, especially of NDVI. The new indices provide good performance in distinguishing aquatic from terrestrial vegetation: NDAVI over low density vegetation (LAI 1.0, FC > 50%). Specific vegetation indices can therefore improve remote sensing applications for aquatic vegetation monitoring.

  12. Heavy metals bioconcentration from soil to vegetables and assessment of health risk caused by their ingestion.

    Science.gov (United States)

    Garg, V K; Yadav, Poonam; Mor, Suman; Singh, Balvinder; Pulhani, Vandana

    2014-03-01

    The present study was undertaken to assess the non-carcinogenic human health risk of heavy metals through the ingestion of locally grown and commonly used vegetables viz. Raphanus sativus (root vegetable), Daucus carota (root vegetable), Benincasa hispida (fruit vegetable) and Brassica campestris leaves (leafy vegetable) in a semi-urbanized area of Haryana state, India. Heavy metal quantification of soil and vegetable samples was done using flame atomic absorption spectrophotometer. Lead, cadmium and nickel concentration in vegetable samples varied in range of 0.12-6.54 mg kg(-1), 0.02-0.67 mg kg(-1) and vegetable samples exceeded maximum permissible limit given by World Health Organization/Food and Agriculture Organization and Indian standards. Much higher concentrations of Pb (40-190.5 mg kg(-1)), Cd (0.56-9.85 mg kg(-1)) and Ni (3.21-45.87 mg kg(-1)) were reported in corresponding vegetable fields' soils. Correlation analysis revealed the formation of three primary clusters, i.e. Cu-Cd, Cd-Pb and Ni-Zn in vegetable fields' soils further supported by cluster analysis and principal component analysis. Bioconcentration factor revealed that heavy metals' uptake was more by leafy vegetable than root and fruit vegetables. Hazard index of all the vegetables was less than unity; thus, the ingestion of these vegetables is unlikely to pose health risks to the target population.

  13. Ecotoxicity of sediments in rivers: Invertebrate community, toxicity bioassays and the toxic unit approach as complementary assessment tools

    OpenAIRE

    Castro-Català, Núria de; Kuzmanović, Maja; Roig, Neus; Sierra, Jordi; Ginebreda, Antoni; Barceló i Cullerés, Damià; Pérez, Sandra; Petrović, Mira; Picó, Yolanda; Schuhmacher, Marta; Muñoz, Isabel

    2016-01-01

    The determination of the real toxicity of sediments in aquatic ecosystems is challenging and necessary for an appropriate risk assessment. Different approaches have been developed and applied over the last several decades. Currently, the joint implementation of chemical, ecological and toxicological tools is recommended for an appropriate and successful toxicity risk assessment. We chose the combination of the toxic unit approach with acute pore water tests (Vibrio fischeri, Pseudokirchneriel...

  14. Human toxicity potentials for life-cycle assessment and toxics release inventory risk screening.

    Science.gov (United States)

    Hertwich, E G; Mateles, S F; Pease, W S; McKone, T E

    2001-04-01

    The human toxicity potential (HTP), a calculated index that reflects the potential harm of a unit of chemical released into the environment, is based on both the inherent toxicity of a compound and its potential dose. It is used to weight emissions inventoried as part of a life-cycle assessment (LCA) or in the toxics release inventory (TRI) and to aggregate emissions in terms of a reference compound. Total emissions can be evaluated in terms of benzene equivalence (carcinogens) and toluene equivalents (noncarcinogens). The potential dose is calculated using a generic fate and exposure model, CalTOX, which determines the distribution of a chemical in a model environment and accounts for a number of exposure routes, including inhalation, ingestion of produce, fish, and meat, and dermal contact with water and soil. Toxicity is represented by the cancer potency q1* for carcinogens and the safe dose (RfD, RfC) for noncarcinogens. This article presents cancer and noncancer HTP values for air and surface-water emissions of 330 compounds. This list covers 258 chemicals listed in U.S. Environmental Protection Agency TRI, or 79 weight-% of the TRI releases to air reported in 1997.

  15. Monitoring of Pesticide Residues in Fruits and Vegetables and Related Health Risk Assessment in Kumasi Metropolis, Ghana

    Directory of Open Access Journals (Sweden)

    Crentsil Kofi Bempah

    2011-11-01

    Full Text Available The objective of present research study was to assess the concentration of pesticide residues in fruits and vegetables from markets in Kumasi and to generate awareness about the lethal effects of these pesticides on human beings as well as to estimate the potential health risks associated with the pesticide residue with regard to consumers. A total of 350 locally produced fruits and vegetables were purchased from six main markets in Kumasi and analyzed by gas chromatography equipped with electron capture detector for organochlorine (gamma-HCH, methoxychlor, aldrin, dieldrin, endrin, p,p’-DDE, p,p’-DDT and pyrethroid (permethrin, cyfluthrin, cypermethrin, fenvalerate, deltamethrin residues. The residual concentrations of selected pesticides in the various fruit and vegetable samples and the potential health risks associated with the exposure to these pesticides were also assessed. The results obtained showed that 37.5% of the fruit and vegetable samples analyzed contained no detectable level of the monitored pesticides, 19.0% of the samples gave results with levels of insecticides residues above the MRL, while 43.5% of the samples showed results below the MRL. The analysis of health risk estimates revealed that none of the pesticides exceeded the reference dose in both fruit and vegetables except endrin which exceeded reference dose in vegetables, suggesting a great potential for systemic toxicity in children considered the most vulnerable population subgroup. Based on observations made in these studies, it is proposed that more extensive monitoring investigation covering all fruits and vegetables in all the ten regions of Ghana be carried out to find the exact position of pesticide residues.

  16. Assessment of heavy metal contents of green leafy vegetables

    OpenAIRE

    Gupta, Sapana; Jena, V.; Jena, S.; Davić, Neda; Matić, Natalija; Radojević, D.; Solanki, J. S.

    2013-01-01

    Vegetables are rich sources of vitamins, minerals, and fibers, and have beneficial antioxidative effects. Ingestion of vegetables containing heavy metals is one of the main routes through which these elements enter the human body. Slowly released into the body, however, heavy metals can cause an array of diseases. In this study we investigated the concentrations of copper, chromium, zinc, and lead in the most frequently consumed vegetables including Pimpinella anisum, Spinacia oleracea, Amara...

  17. Comprehensive assessment of toxic chemical pollutants at Trombay region

    International Nuclear Information System (INIS)

    Anthropogenic activities like industrial production and transportation, a wide range of chemical pollutants such as trace and toxic metals, pesticides, polycyclic aromatic hydrocarbons etc. eventually found their way into various environmental compartments. These pollutants get distributed among soil, water bodies, air and if left unattended can cause serious health risk to all exposed ecosystem components including human beings. These compounds may produce immediate toxicity to ecosystems or exhibit long term effects such as mutagenicity, carcinogenicity or biomagnify (concentrations of pollutant increase per unit body weight) in higher trophic organism of the food chain. Thus regular monitoring of these toxic chemicals in all the environmental matrices is unquestionably essential for reclaiming our natural resources. This report describes some of the activities of Environmental Assessment Division which are having direct relevance to the public health and regulatory bodies. Extensive studies were carried out in our laboratories for the Trombay site, over the years; on the organic as well as inorganic pollution in the environment to understand inter compartmental behaviour of these chemical pollutants. In this report attempt has been made to compare the data on various toxic chemical pollutants that are being monitored regularly at Trombay site and their levels are compared with existing regulations. For monitoring, methodologies have been standardized for characterization of toxic chemical pollutants using different analytical techniques. Regular sample collection from different environmental matrices has been done. Sample analysis has been carried out using different analytical instruments such as high performance liquid chromatograph, ion chromatograph, gas chromatograph, atomic absorption spectrophotometer, and differential pulse anodic stripping voltammetry. Major portion of the study covers Air quality monitoring of toxic chemical pollutants, as the other

  18. [Assessment of fruit and vegetable intake among the 50-year-old population of Wroclaw].

    Science.gov (United States)

    Ilow, Rafał; Regulska-Ilow, Bozena; Misiewicz, Dominika; Rózańska, Dorota; Kowalisko, Alicja; Biernat, Jadwiga

    2011-01-01

    Intake of fruit and vegetable among 50-year-old population of Wroclaw and the impact of education level on the consumption of fruits and vegetables was assessed. The study group was 50-year-old, 1520 inhabitants of Wroclaw (879 women and 641 men), who participated in 2008 in the Cardiovascular Diseases Prevention Program organized by the Health Division of the Municipal Office in Wroclaw. To assess fruit and vegetable intake Food Frequency Questionnaire (FFQ) was used. The mean daily intake of vegetables and fruit was 289,4 g for women and 209,1 g for men. Women consumed significantly more vegetables, fruits, and the amounts of fruits and vegetables compared with men. The impact of educational level on fruit and vegetable consumption in the study group was found.

  19. Accuracy Assessment Point for Fire Island National Seashore Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This dataset was compiled to provide users with the geographic locations of the accuracy assessment plots used to assess the Fire Island Vegetation Map...

  20. Accuracy Assessment Points for Valley Forge National Historical Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This shapefile includes the accuracy assessment points used to assess the association-level vegetation map of Valley Forge National Historic Park developed by the...

  1. Accuracy Assessment Points for Hopewell Furnace National Historic Site Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This shapefile includes the accuracy assessment points used to assess the alliance-level vegetation map of Hopewell Furnace National Historic Site (HOFU) developed...

  2. Accuracy Assessment Points for Gateway National Recreation Area Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Location of thematic accuracy assessment sampling points, that were field sampled, based on the destination accuracy assessment points used in the vegetation...

  3. Assessing vegetation response to drought in the northern Great Plains using vegetation and drought indices

    Science.gov (United States)

    Ji, Lei; Peters, Albert J.

    2003-01-01

    The Normalized Difference Vegetation Index (NDVI) derived from the Advanced Very High Resolution Radiometer (AVHRR) has been widely used to monitor moisture-related vegetation condition. The relationship between vegetation vigor and moisture availability, however, is complex and has not been adequately studied with satellite sensor data. To better understand this relationship, an analysis was conducted on time series of monthly NDVI (1989–2000) during the growing season in the north and central U.S. Great Plains. The NDVI was correlated to the Standardized Precipitation Index (SPI), a multiple-time scale meteorological-drought index based on precipitation. The 3-month SPI was found to have the best correlation with the NDVI, indicating lag and cumulative effects of precipitation on vegetation, but the correlation between NDVI and SPI varies significantly between months. The highest correlations occurred during the middle of the growing season, and lower correlations were noted at the beginning and end of the growing season in most of the area. A regression model with seasonal dummy variables reveals that the relationship between the NDVI and SPI is significant in both grasslands and croplands, if this seasonal effect is taken into account. Spatially, the best NDVI–SPI relationship occurred in areas with low soil water-holding capacity. Our most important finding is that NDVI is an effective indicator of vegetation-moisture condition, but seasonal timing should be taken into consideration when monitoring drought with the NDVI.

  4. Reactor modeling in heterogeneous photocatalysis: toxicity and biodegradability assessment.

    Science.gov (United States)

    Satuf, M L; José, S; Paggi, J C; Brandi, R J; Cassano, A E; Alfano, O M

    2010-01-01

    Photocatalysis employing titanium dioxide is a useful method to degrade a wide variety of organic and inorganic pollutants from water and air. However, the application of this advanced oxidation process at industrial scale requires the development of mathematical models to design and scale-up photocatalytic reactors. In the present work, intrinsic kinetic expressions previously obtained in a laboratory reactor are employed to predict the performance of a bench scale reactor of different configuration and operating conditions. 4-Chlorophenol was chosen as the model pollutant. The toxicity and biodegradability of the irradiated mixture in the bench photoreactor was also assessed. Good agreement was found between simulation and experimental data. The root mean square error of the estimations was 9.9%. The photocatalytic process clearly enhances the biodegradability of the reacting mixture, and the initial toxicity of the pollutant was significantly reduced by the treatment.

  5. Assessing climate refugia from a terrestrial vegetation vulnerability assessment for 29 types in California.

    Science.gov (United States)

    Thorne, J. H.; Bjorkman, J.; Boynton, R.; Stewart, J.; Holguin, A.; Schwartz, M.; Albright, W.

    2015-12-01

    We assessed the climate vulnerability of 29 terrestrial macrogroup vegetation types in the National Vegetation Classification Scheme covering 99% of California. Using a 2015 landcover map, we defined current and future climate exposure of each type by assessing conditions at all known locations. This approach identifies both areas of expected high stress and of climate refugia. Species distribution models of the vegetation types proved to over-predict the extent of occupied lands, compared to their mapped extents. Trait based components of the vulnerability assessment were far less influential on level of vulnerability than climate projection. Various cutoffs can be selected to describe refugia. Here we classed refugia as the 20% of climate conditions most frequently occupied by a type. Under CNRM CM5 RCP 4.5, of 70,143 km2 that are the most climate-insulated locations, 46,420 km2 move to higher levels of climate exposure. At the other extreme of climate projections tested, MIROC ESM RCP 8.5, 59,137 km2 are lost. Four macrogroups lose their refugia under CNRM 4.5: Pacific Northwest Conifer Forests, Mountain Riparian Scrub and Wet Meadow, Salt Marsh, and Great Basin Upland Scrub. Under MIROC 8.5 and additional 8 macrogroups lose the most commonly experienced climate: Subalpine Aspen Forests & Pine Woodlands, Non-Native Forest and Woodlands, North Coast Deciduous Scrub and Terrace Prairie, Coastal Dune and Bluff Scrub, Freshwater Marsh, Wet Mountain Meadow, Big Sagebrush Scrub, and Alpine Vegetation. These results raise interesting questions regarding the definition of refugia. We review the results and ask how appropriate they are for different ecosystem types.

  6. Accuracy Assessment Points for Voyageurs National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Thematic accuracy requirements for the USGS-NPS Vegetation Mapping Program specify 80% accuracy for each map unit that represents USNVC floristic types. A total of...

  7. Fruit and Vegetable Quality Assessment via Dielectric Sensing

    OpenAIRE

    Dalia El Khaled; Nuria Novas; Gazquez, Jose A.; Garcia, Rosa M.; Francisco Manzano-Agugliaro

    2015-01-01

    The demand for improved food quality has been accompanied by a technological boost. This fact enhances the possibility of improving the quality of horticultural products, leading towards healthier consumption of fruits and vegetables. A better electrical characterization of the dielectric properties of fruits and vegetables is required for this purpose. Moreover, a focused study of dielectric spectroscopy and advanced dielectric sensing is a highly interesting topic. This review explains the ...

  8. Concurrent Boost with Adjuvant Breast Hypofractionated Radiotherapy and Toxicity Assessment

    Directory of Open Access Journals (Sweden)

    Mona M. Sayed

    2015-01-01

    Full Text Available Background: The use of shorter radiotherapy schedules has an economic and logistic advantage for radiotherapy departments, as well as a high degree of patient convenience. The aim of this study is to assess the acute and short-term late toxicities of a hypofractionated radiotherapy schedule with a concomitant boost. Methods: We enrolled 57 eligible patients as group A. These patients received 42.5 Gy in 16 fractions of 2.66 Gy each to the whole breast over 3.2 weeks. A concomitant electron boost of 12 Gy in 16 fractions was also administered which gave an additional 0.75 Gy daily to the lumpectomy area for a total radiation dose of 54.5 Gy. Toxicity was recorded at three weeks and at three months for this group as well as for a control group (group B. The control group comprised 76 eligible patients treated conventionally with 50 Gy to the whole breast over five weeks followed by a sequential electron boost of 12 Gy in 2 Gy per fraction. Results: There were no statistically significant differences observed in the incidence of acute skin toxicity, breast pain, and edema recorded at three weeks or pigmentation and fibrosis recorded at three months between the two groups (P0.05. Conclusion: The results of this study suggest there are no increased acute and shortterm late toxicities affiliated with the hypofractionated schedule plus a concomitant boost as prescribed compared to the conventional fractionation of adjuvant breast radiotherapy. Large randomized trials and long-term follow-up are needed to confirm these favorable findings.

  9. Assessment of the impacts of gold mining on soil and vegetation in Brownsberg Nature Park, Suriname

    NARCIS (Netherlands)

    Arets, E.J.M.M.; Meer, van der P.J.; Brink, van den N.W.; Tjon, K.; Atmopawiro, V.P.; Ouboter, P.E.

    2006-01-01

    This report describes the assessment of the impacts of small scale gold-mining on soil and vegetation in Brownsberg Nature Park. In the past 10 years small-scale gold mining with heavy machinery has been illegally practiced within Brownsberg Nature Park (BNP). During this process the vegetation and

  10. MARKETING FRUIT AND VEGETABLES TO MIDDLE SCHOOL STUDENTS: FORMATIVE ASSESSMENT RESULTS

    Science.gov (United States)

    Middle school student consumption of fruit and vegetables is lower than that of elementary school students. A formative assessment was conducted to help plan a social marketing campaign to encourage fruit and vegetable purchase and consumption in middle school snack bars. Individual interviews were ...

  11. Assessment of the Aerosol Generation and Toxicity of Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Patrick T. O'Shaughnessy

    2014-06-01

    Full Text Available Current interest in the pulmonary toxicity of carbon nanotubes (CNTs has resulted in a need for an aerosol generation system that is capable of consistently producing a CNT aerosol at a desired concentration level. This two-part study was designed to: (1 assess the properties of a commercially-available aerosol generator when producing an aerosol from a purchased powder supply of double-walled carbon nanotubes (DWCNTs; and (2 assess the pulmonary sub-acute toxicity of DWCNTs in a murine model during a 5-day (4 h/day whole-body exposure. The aerosol generator, consisting of a novel dustfeed mechanism and venturi ejector was determined to be capable of producing a DWCNT consistently over a 4 h exposure period at an average level of 10.8 mg/m3. The count median diameter was 121 nm with a geometric standard deviation of 2.04. The estimated deposited dose was 32 µg/mouse. The total number of cells in bronchoalveolar lavage (BAL fluid was significantly (p < 0.01 increased in exposed mice compared to controls. Similarly, macrophages in BAL fluid were significantly elevated in exposed mice, but not neutrophils. All animals exposed to CNT and euthanized immediately after exposure had changes in the lung tissues showing acute inflammation and injury; however these pathological changes resolved two weeks after the exposure.

  12. Assessing landscape changes in Laos using MODIS Enhanced Vegetation Index

    OpenAIRE

    Hett, Cornelia; Hurni, Kaspar; Heinimann, Andreas; Mueller, Daniel

    2010-01-01

    The ongoing rapid and vast land cover and land use transformations in Laos are only documented by punctual local case studies; information on national level is barely available. We explore ways to address this by using MODIS vegetation index times series data to detect medium to large scale transformation on the national level.

  13. Heavy metals toxicity and bioaccumulation in vegetables from potentially polluted area

    OpenAIRE

    Balabanova, Biljana; Stafilov, Trajče; Baceva, Katerina; Vuckovic, Ivana

    2013-01-01

    Food safety and quality are a major public concern worldwide, regarding the risk associated with consumption of food stuffs contaminated with heavy metals as toxins. The levels of 8 elements contents were determined in various vegetables [garlic (Allium sativum), onion (Allium cepa) and parsley (Petroselinum crispum)], cultivated around copper mine environ. Bioaccumulation and mobility of heavy metals were determinate with three soil extraction methods: in 0.1 M HCl; in H2O and in a mixed buf...

  14. Kaloko-Honokohau National Historical Park Vegetation Mapping Project - Field Plots, Observation and Accuracy Assessment Points

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the 2008 vegetation (classification) field plots (spatial database) and 2010 accuracy assessment points (spatial database) created from the...

  15. Accuracy Assessment Points for Florissant Fossil Beds National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The accuracy assessment field work was performed in July - August, 2001 to verify the accuracy of the vegetation communities spatial data developed by the USGS-NPS...

  16. Accuracy Assessment Points for Fort Laramie National Historic Site Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The accuracy assessment field work was performed in August and September, 1998 to verify the accuracy of the vegetation communities spatial data developed by the...

  17. Accuracy Assessment Points for Colonial National Historical Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This shapefile depicts the locations of thematic accuracy assessment sampling points used in the vegetation mapping of Colonial National Historical Park. It was...

  18. Accuracy Assessment Points for Appomattox Court House National Historical Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This shapefile depicts the locations of thematic accuracy assessment sampling points used in the vegetation mapping of Appomottox Court House National Historical...

  19. Accuracy Assessment Points for Devils Tower National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The accuracy assessment field work was performed in July and August, 1996 to verify the accuracy of the vegetation communities spatial data developed by the...

  20. Accuracy Assessment Points Modified for Delaware Water Gap National Recreation Area Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Location of thematic accuracy assessment sampling points used in the vegetation and fire fuel model mapping in Delaware Water Gap National Recreation Area. In this...

  1. Accuracy Assessment Points for Natural Bridges National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This point file displays the 288 accuracy assessment (AA) points visited in the fall of 2004 as part of the vegetation mapping project. The points were randomly...

  2. Accuracy Assessment Points for Fredericksburg and Spotsylvania National Military Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This shapefile depicts the locations of thematic accuracy assessment sampling points used in the vegetation mapping of Fredericksburg and Spotsylvania National...

  3. Accuracy Assessment Points for Capitol Reef National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This point file displays the 1,313 accuracy assessment (AA) points visited in the summer of 2005 as part of the vegetation mapping project. The points were randomly...

  4. Field Plot and Accuracy Assessment Points for Shenandoah National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This data set is an ESRI point shapefile. Points represent vegetation and accuracy assessment plots from which field data were collected as part of the Version 2.0...

  5. Accuracy Assessment Points for Scotts Bluff National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The accuracy assessment field work was performed in August, 1997 to verify the accuracy of the vegetation communities spatial data developed by the USGS-NPS...

  6. Accuracy Assessment Points for Richmond National Battlefield Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This shapefile depicts the locations of thematic accuracy assessment sampling points used in the vegetation mapping of Richmond National Battlefield Park. It was...

  7. Accuracy Assessment Points for Walnut Canyon National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This spatial dataset in ESRI Coverage format maps accuracy assessment point locations for the vegetation map at Walnut Canyon National Monument and in the...

  8. Accuracy Assessment Points for Mount Rushmore National Memorial Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The accuracy assessment field work was performed in July and August, 1996 to verify the accuracy of the vegetation communities spatial data developed by the...

  9. Accuracy Assessment Points for Black Canyon of the Gunnison National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This point file displays the 757 accuracy assessment (AA) points visited in the late summer of 2004 as part of the vegetation mapping project. The points were...

  10. Accuracy Assessment Points for Fossil Butte National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This point file displays the 661 accuracy assessment (AA) points visited in the late summer of 2006 as part of the vegetation mapping project. The points were...

  11. Accuracy Assessment Points for Theodore Roosevelt National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the accuracy assessment data associated with the vegetation land cover and land use geospatial database for Theodore Roosevelt National Park...

  12. Assessing aluminium toxicity in streams affected by acid mine drainage.

    Science.gov (United States)

    Waters, A S; Webster-Brown, J G

    2013-01-01

    Acid mine drainage (AMD) has degraded water quality and ecology in streams on the Stockton Plateau, the site of New Zealand's largest open-cast coal mining operation. This has previously been attributed largely to the effects of acidity and elevated aluminium (Al) concentrations. However, the toxicity of dissolved Al is dependent on speciation, which is influenced by pH which affects Al hydrolysis, as well as the concentrations of organic carbon and sulphate which complex Al. Methods for the assessment of the toxic fraction of Al, by chemical analysis and geochemical modelling, have been investigated in selected streams on the Stockton Plateau, where dissolved Al concentrations ranged from 0.034 to 27 mg L(-1). Modelling using PHREEQC indicated that between 0.2 and 85% of the dissolved Al was present as the free ion Al(3+), the most toxic Al species, which dominated in waters of pH = 3.8-4.8. Al-sulphate complexation reduced the Al(3+) concentration at lower pH, while Al-organic and -hydroxide complexes dominated at higher pH. Macroinvertebrate richness in the streams identified an Al(3+) 'threshold' of approximately 0.42 mg/L, above which taxa declined rapidly. Colorimetric 'Aluminon' analysis on unpreserved, unfiltered waters provided a better estimation of Al(3+) concentrations than inductively couple plasma-mass spectrometry (ICP-MS) on filtered, acidified waters. The Aluminon method does not react with particulate Al or strong Al complexes, often registering as little as 53% of the dissolved Al concentration determined by ICP-MS. PMID:23579831

  13. Assessing the toxicity and biodegradability of deep eutectic solvents.

    Science.gov (United States)

    Wen, Qing; Chen, Jing-Xin; Tang, Yu-Lin; Wang, Juan; Yang, Zhen

    2015-08-01

    Deep eutectic solvents (DESs) have emerged as a new type of promising ionic solvents with a broad range of potential applications. Although their ecotoxicological profile is still poorly known, DESs are generally regarded as "green" because they are composed of ammonium salts and H-bond donors (HBDs) which are considered to be eco-friendly. In this work, cholinium-based DESs comprised of choline chloride (ChCl) and choline acetate (ChAc) as the salt and urea (U), acetamide (A), glycerol (G) and ethylene glycol (EG) as the HBD were evaluated for their toxic effects on different living organisms such as Escherichia coli (a bacterium), Allium sativum (garlic, a plant) and hydra (an invertebrate), and their biodegradabilities were assessed by means of closed bottle tests. These DESs possessed an anti-bacterial property and exhibited inhibitory effects on the test organisms adopted, depending on the composition and concentration of the DES. The mechanism for the impact of DESs and their components on different living organisms can be associated to their interactions with the cellular membranes. Not all DESs can be considered readily biodegradable. By extending the limited knowledge about the toxicity and biodegradation of this particular solvent family, this investigation on DESs provides insight into our structure-based understanding of their ecotoxicological behavior. PMID:25800513

  14. IN VIVO TOXICITY ASSESSMENT OF SILICA NANOPARTICLES IN CHICK EMBRYO

    Directory of Open Access Journals (Sweden)

    Chandrapragasam Vani

    2013-09-01

    Full Text Available Silica is one of the most effective stored seedand food grain protecting pesticide agent, usedfor ages Silica nanoparticles are hard and strong andresistant to brittle fracture under an imposed stress. The aim of our study is to synthesize and evaluate the toxicity of silica nanoparticles at various concentrations using chick embryo, as it serves as a bridging model between in vivo and ex vivo studies. Silica nanoparticles of 70 nm sizewith concentrations of 10, 20, 40 and 80 PPM were injected in vivo and incubated for 19 days as per IACUC guidelines. The study was carried out on dissected chick embryo after the 19th day of incubation. Vital tissues such as liver and heart tissues were subjected to toxicity assays. Biochemical assay of antioxidant enzymes like superoxide dismutase and glutathione peroxide were assessed. The results showed a decreased level of MDA (Malondialdehyde, an end product of lipid Peroxidation, whereas increased activity of superoxide dismutase and glutathione peroxide were observed. Therefore silica nanoparticles may be used as a pesticide and also as a biomaterial for therapeutic application in the field of medicine.

  15. Global assessment of experimental climate warming on tundra vegetation

    DEFF Research Database (Denmark)

    Elmendorf, Sarah C.; Henry, Gregory H.R.; Hollister, Robert D.;

    2012-01-01

    Understanding the sensitivity of tundra vegetation to climate warming is critical to forecasting future biodiversity and vegetation feedbacks to climate. In situ warming experiments accelerate climate change on a small scale to forecast responses of local plant communities. Limitations...... of this approach include the apparent site-specificity of results and uncertainty about the power of short-term studies to anticipate longer term change. We address these issues with a synthesis of 61 experimental warming studies, of up to 20 years duration, in tundra sites worldwide. The response of plant groups...... to warming often differed with ambient summer temperature, soil moisture and experimental duration. Shrubs increased with warming only where ambient temperature was high, whereas graminoids increased primarily in the coldest study sites. Linear increases in effect size over time were frequently observed...

  16. Assessment of biochemical concentrations of vegetation using remote sensing technology

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The main biochemicals (such as lignin, protein, cellulose, sugar, starch, chlorophyll and water) of vegetation are directly or indirectly involved in major ecological processes, such as the functions of terrestrial ecosystems (i.e., nutrient-cycling processes, primary production, and decomposition). Remote sensing techniques provide a very convenient way of data acquisition capable of covering a large area several times during one season, so it can play a unique and essential role provided that we can relate remote sensing measurements to the biochemical characteristics of the Earth surface in a reliable and operational way. The application of remote sensing techniques for the estimation of canopy biochemicals was reviewed. Three methods of estimating biochemical concentrations of vegetation were included in this paper: index, stepwise multiple linear regression, and stepwise multiple linear regression based on a model of the forest crown. In addition, the vitality and potential applying value are stressed.

  17. Fruit and Vegetable Quality Assessment via Dielectric Sensing

    Directory of Open Access Journals (Sweden)

    Dalia El Khaled

    2015-06-01

    Full Text Available The demand for improved food quality has been accompanied by a technological boost. This fact enhances the possibility of improving the quality of horticultural products, leading towards healthier consumption of fruits and vegetables. A better electrical characterization of the dielectric properties of fruits and vegetables is required for this purpose. Moreover, a focused study of dielectric spectroscopy and advanced dielectric sensing is a highly interesting topic. This review explains the dielectric property basics and classifies the dielectric spectroscopy measurement techniques. It comprehensively and chronologically covers the dielectric experiments explored for fruits and vegetables, along with their appropriate sensing instrumentation, analytical modelling methods and conclusions. An in-depth definition of dielectric spectroscopy and its usefulness in the electric characterization of food materials is presented, along with the various sensor techniques used for dielectric measurements. The collective data are tabulated in a summary of the dielectric findings in horticultural field investigations, which will facilitate more advanced and focused explorations in the future.

  18. Assessing Sahelian vegetation and stress from seasonal time series of polar orbiting and geostationary satellite imagery

    DEFF Research Database (Denmark)

    Olsen, Jørgen Lundegaard

    provide good sensitivity to canopy water content, which can make vegetation stress detection possible. Furthermore, the high frequency observations in the optical spectrum now available from geostationary instruments have the potential for detection of changes in vegetation related surface properties...... are also compared with output from hydrological modelling of the Senegal River basin and a gridded rainfall product. It was shown that NIR/SWIR based indices are better suited for assessing water stress related changes in vegetation status, as compared to the more commonly applied NDVI. The hypothesis...... that short term variations in anomalies from seasonally detrended time series of indices could carry information on vegetation stress was examined and confirmed. However, it was not found sufficiently robust on pixel level to be implemented for monitoring vegetation water stress on a per-pixel basis...

  19. Improving Toxicity Assessment of Pesticide Mixtures: The Use of Polar Passive Sampling Devices Extracts in Microalgae Toxicity Tests.

    Science.gov (United States)

    Kim Tiam, Sandra; Fauvelle, Vincent; Morin, Soizic; Mazzella, Nicolas

    2016-01-01

    Complexity of contaminants exposure needs to be taking in account for an appropriate evaluation of risks related to mixtures of pesticides released in the ecosystems. Toxicity assessment of such mixtures can be made through a variety of toxicity tests reflecting different level of biological complexity. This paper reviews the recent developments of passive sampling techniques for polar compounds, especially Polar Organic Chemical Integrative Samplers (POCIS) and Chemcatcher® and the principal assessment techniques using microalgae in laboratory experiments. The progresses permitted by the coupled use of such passive samplers and ecotoxicology testing as well as their limitations are presented. Case studies combining passive sampling devices (PSD) extracts and toxicity assessment toward microorganisms at different biological scales from single organisms to communities level are presented. These case studies, respectively, aimed (i) at characterizing the "toxic potential" of waters using dose-response curves, and (ii) at performing microcosm experiments with increased environmental realism in the toxicant exposure in term of cocktail composition and concentration. Finally perspectives and limitations of such approaches for future applications in the area of environmental risk assessment are discussed. PMID:27667986

  20. Improving Toxicity Assessment of Pesticide Mixtures: The Use of Polar Passive Sampling Devices Extracts in Microalgae Toxicity Tests

    Science.gov (United States)

    Kim Tiam, Sandra; Fauvelle, Vincent; Morin, Soizic; Mazzella, Nicolas

    2016-01-01

    Complexity of contaminants exposure needs to be taking in account for an appropriate evaluation of risks related to mixtures of pesticides released in the ecosystems. Toxicity assessment of such mixtures can be made through a variety of toxicity tests reflecting different level of biological complexity. This paper reviews the recent developments of passive sampling techniques for polar compounds, especially Polar Organic Chemical Integrative Samplers (POCIS) and Chemcatcher® and the principal assessment techniques using microalgae in laboratory experiments. The progresses permitted by the coupled use of such passive samplers and ecotoxicology testing as well as their limitations are presented. Case studies combining passive sampling devices (PSD) extracts and toxicity assessment toward microorganisms at different biological scales from single organisms to communities level are presented. These case studies, respectively, aimed (i) at characterizing the “toxic potential” of waters using dose-response curves, and (ii) at performing microcosm experiments with increased environmental realism in the toxicant exposure in term of cocktail composition and concentration. Finally perspectives and limitations of such approaches for future applications in the area of environmental risk assessment are discussed. PMID:27667986

  1. Assessment of drought impacts on vegetation health: a case study in Kedah

    Science.gov (United States)

    Othman, M.; Ash'aari, Z. H.; Muharam, F. M.; Sulaiman, W. N. A.; Hamisan, H.; Mohamad, N. D.; Othman, N. H.

    2016-06-01

    Prolonged drought in the early of 2014 has caused Malaysia to experience water supply shortage which directly affects both health and growth of vegetation. Thus this study aims to assess the risk vegetation areas that were impacted during 2014’s drought by integrating the Standardized Precipitation Index (SPI) and Normalized Differentiation Vegetation Index (NDVI) methods. These two methods were able to assess the risk areas for the vegetation by measuring its health and classifying them according to its severity while considering the rainfall reduction at the specific time and location. The results obtained from this study shows that the central and north west of Kedah was vulnerable to the occurrence of drought. Kedah was more impacted by the dry event during the northeast monsoon. This study is significant as a fundamental input for further research and as an alternative approach by the application of space technology.

  2. A test strategy for the assessment of additive attributed toxicity of tobacco products.

    Science.gov (United States)

    Kienhuis, Anne S; Staal, Yvonne C M; Soeteman-Hernández, Lya G; van de Nobelen, Suzanne; Talhout, Reinskje

    2016-08-01

    The new EU Tobacco Product Directive (TPD) prohibits tobacco products containing additives that are toxic in unburnt form or that increase overall toxicity of the product. This paper proposes a strategy to assess additive attributed toxicity in the context of the TPD. Literature was searched on toxicity testing strategies for regulatory purposes from tobacco industry and governmental institutes. Although mainly traditional in vivo testing strategies have been applied to assess toxicity of unburnt additives and increases in overall toxicity of tobacco products due to additives, in vitro tests combined with toxicogenomics and validated using biomarkers of exposure and disease are most promising in this respect. As such, tests are needed that are sensitive enough to assess additive attributed toxicity above the overall toxicity of tobacco products, which can associate assay outcomes to human risk and exposure. In conclusion, new, sensitive in vitro assays are needed to conclude whether comparable testing allows for assessment of small changes in overall toxicity attributed to additives. A more pragmatic approach for implementation on a short-term is mandated lowering of toxic emission components. Combined with risk assessment, this approach allows assessment of effectiveness of harm reduction strategies, including banning or reducing of additives.

  3. Distribution and Risk Assessment of Polycyclic Aromatic Hydrocarbons in Vegetables Grown in Pakistan

    OpenAIRE

    Ashraf, Mohammad W.; Syed Iqleem H. Taqvi; Solangi, Amber R.; Qureshi, Umair A.

    2013-01-01

    Distribution and risk assessment of eight priority polycyclic aromatic hydrocarbons (PAHs) contents have been examined in different varieties of vegetables grown in Pakistan. The results showed that the total PAH contents were higher for root vegetables like potato and carrot (~13 μg/kg) and relatively lower for turnip (10.9 μg/kg), respectively while for the fruit vegetables, all the peels were found to be more contaminated than cores. The ratio of total PAH concentrations in peels with resp...

  4. A visual assessment of vegetation structure for the Kruger National Park

    Directory of Open Access Journals (Sweden)

    A.C. Kemp

    1997-02-01

    Full Text Available Vegetation structure was assessed visually for 1045 of the 1093 quadrats (2.5' x 2.5', ca 4 x 4 km that cover the Kruger National Park. Vegetation categories recorded were-woody vegetation (broad-leaved, mopane, fine-leaved, mixed, riparian, treeless, scrub bushes and trees; ground cover (grass, grassless and open areas; and emergent large trees (baobab, live and dead. The results are available as grid maps or as files on the Internet. The categories were selected for their relevance to bird distribution but can be applied to other organisms.

  5. Restoration or Disturbance: Assessing the Impacts of a Salmon Habitat Restoration Project on Riparian Vegetation Composition

    OpenAIRE

    Azevedo, Andhra; Chin, Larissa; Dullemond, Kia; Morton, Lovena; Naghshinepour, Negar; Salihue, Hafsa

    2013-01-01

    Invasive plant species can threaten the biodiversity and resilience of riparian ecosystems. A vegetation assessment of the riparian zone beside the Stoney Creek Off-Channel Habitat Project compared with a non-restored site and a previously replanted site showed that the sites were significantly different in their vegetation composition. All three sites had several invasive species of concern playing dominant roles in the ecosystem with the most common two species being English ivy (Hedera hel...

  6. Use of vegetation to ameliorate building microclimates: an assessment of energy-conservation potentials

    Energy Technology Data Exchange (ETDEWEB)

    Hutchison, B.A.; Taylor, F.G.; Wendt, R.L.

    1982-04-01

    The space-conditioning energy conservation potentials of landscapes designed to ameliorate building microclimates are evaluated. The physical bases for vegetative modifications of climate are discussed, and results of past study of the effects of vegetation on space-conditioning energy consumption in buildings are reviewed. The state-of-the-art of energy-conserving landscape designs is assessed and recommendations are presented for further research.

  7. Global changes in dryland vegetation dynamics (1988–2008 assessed by satellite remote sensing: comparing a new passive microwave vegetation density record with reflective greenness data

    Directory of Open Access Journals (Sweden)

    N. Andela

    2013-10-01

    Full Text Available Drylands, covering nearly 30% of the global land surface, are characterized by high climate variability and sensitivity to land management. Here, two satellite-observed vegetation products were used to study the long-term (1988–2008 vegetation changes of global drylands: the widely used reflective-based Normalized Difference Vegetation Index (NDVI and the recently developed passive-microwave-based Vegetation Optical Depth (VOD. The NDVI is sensitive to the chlorophyll concentrations in the canopy and the canopy cover fraction, while the VOD is sensitive to vegetation water content of both leafy and woody components. Therefore it can be expected that using both products helps to better characterize vegetation dynamics, particularly over regions with mixed herbaceous and woody vegetation. Linear regression analysis was performed between antecedent precipitation and observed NDVI and VOD independently to distinguish the contribution of climatic and non-climatic drivers in vegetation variations. Where possible, the contributions of fire, grazing, agriculture and CO2 level to vegetation trends were assessed. The results suggest that NDVI is more sensitive to fluctuations in herbaceous vegetation, which primarily uses shallow soil water, whereas VOD is more sensitive to woody vegetation, which additionally can exploit deeper water stores. Globally, evidence is found for woody encroachment over drylands. In the arid drylands, woody encroachment appears to be at the expense of herbaceous vegetation and a global driver is interpreted. Trends in semi-arid drylands vary widely between regions, suggesting that local rather than global drivers caused most of the vegetation response. In savannas, besides precipitation, fire regime plays an important role in shaping trends. Our results demonstrate that NDVI and VOD provide complementary information and allow new insights into dryland vegetation dynamics.

  8. Development of a Fully Automated Flow Injection Analyzer Implementing Bioluminescent Biosensors for Water Toxicity Assessment

    OpenAIRE

    Constantinos Georgiou; Georgakopoulos, Dimitrios G.; Gerasimos Kremmydas; Efstathios Vasiliou; Efstratios Komaitis

    2010-01-01

    This paper describes the development of an automated Flow Injection analyzer for water toxicity assessment. The analyzer is validated by assessing the toxicity of heavy metal (Pb2+, Hg2+ and Cu2+) solutions. One hundred μL of a Vibrio fischeri suspension are injected in a carrier solution containing different heavy metal concentrations. Biosensor cells are mixed with the toxic carrier solution in the mixing coil on the way to the detector. Response registered is % inhibition of biosensor biol...

  9. National Air Toxics Assessment - 2002, EPA Region 2 (EPA.AIR.NATA99_R2)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer is based on the model results of the 1999 National-Scale Assessment (N-SA), a part of the National Air Toxics Assessment (NATA), conducted by EPA's...

  10. National Air Toxics Assessment - 2005, EPA Region 2 (EPA.AIR.NATA99_R2)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer is based on the model results of the 1999 National-Scale Assessment (N-SA), a part of the National Air Toxics Assessment (NATA), conducted by EPA's...

  11. National Air Toxics Assessment - 1999, EPA Region 2 (EPA.AIR.NATA99_R2)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer is based on the model results of the 1999 National-Scale Assessment (N-SA), a part of the National Air Toxics Assessment (NATA), conducted by EPA's...

  12. ROLE OF TOXICITY ASSESSMENT AND MONITORING IN MANAGING THE RECOVERY OF A WASTEWATER RECEIVING STREAM

    Energy Technology Data Exchange (ETDEWEB)

    Greeley Jr, Mark Stephen [ORNL; Kszos, Lynn A [ORNL; Stewart, Arthur J [ORNL; Smith, John G [ORNL

    2011-01-01

    We evaluate the roles of a long-term comprehensive toxicity assessment and monitoring program in management and for ecological recovery of a freshwater receiving stream impacted by industrial discharges and legacy contamination. National Pollution Discharge Elimination Permit (NPDES)-driven whole effluent toxicity (WET) tests using Ceriodaphnia and fathead minnows were conducted for more than twenty years to characterize wastewaters at the US National Nuclear Security Agency s Y-12 National Security Complex in Oak Ridge, Tennessee. Ambient toxicity tests also were conducted to assess water samples from EFPC, the stream receiving the wastewater discharges. The ambient tests were conducted as part of an extensive biological monitoring program that included routine surveys of fish, invertebrate and periphyton communities. WET testing, associated toxicant identification evaluations (TIEs), and ambient toxicity monitoring were instrumental in identifying toxicants and their sources at the Y-12 Complex, guiding modifications to wastewater treatment procedures, and assessing the success of various pollution-abatement actions. Through time, as requirements changed and water quality improved, the toxicity monitoring program became more focused. Ambient testing with Ceriodaphnia and fathead minnow larvae also was supplemented with less-standardized but more-sensitive alternative laboratory and in situ bioassays. The Y-12 Complex biological monitoring experience demonstrates the significant roles effluent and ambient toxicity testing can have in controlling and managing toxic discharges to receiving waters. It also emphasizes the value of supplementing WET and standardized ambient toxicity tests with alternative laboratory and in situ toxicity tests tailored to address specific problems.

  13. Food plant toxicants and safety - Risk assessment and regulation of inherent toxicants in plant foods

    DEFF Research Database (Denmark)

    Essers, A.J.A.; Alink, G.M.; Speijers, G.J.A.;

    1998-01-01

    The ADI as a tool for risk management and regulation of food additives and pesticide residues is not readily applicable to inherent food plant toxicants: The margin between actual intake and potentially toxic levels is often small; application of the default uncertainty factors used to derive ADI...... values, particularly when extrapolating from animal data, would prohibit the utilisation of the food, which may have an overall beneficial health effect. Levels of inherent toxicants are difficult to control; their complete removal is not always wanted, due to their function for the plant or for human...... health. The health impact of the inherent toxicant is often modified by factors in the food, e.g. the bioavailability from the matrix and interaction with other inherent constituents. Risk-benefit analysis should be made for different consumption scenarios, without the use of uncertainty factors. Crucial...

  14. Assessment and study of changes psychosomatic state of the vegetative nervous system of patients with rosacea

    Directory of Open Access Journals (Sweden)

    Davydova A.V.

    2012-06-01

    Full Text Available

    Aims. The study aimed an identifying of signs of the vegetative nervous system and detailed study of the psychological characteristics of patients with rosacea. Materials and methods. The study included 60 patients with different clinical forms of rosacea at the age from 26 to 56 years and a control group of 60 relatively healthy persons. The assessment of emotional status is carried out with the survey, Test of accentuations of temperament, Diagnostic Questionnaire Quality of Life Index (DILQ, The Zung Self-Rating Depression Scale, reduced multifactorial questionnaire for the study of personality. Vegetative nervous system was investigated using vegetative Kerdo index, Wayne and Solovyova tables and a special questionnaire for signs of vegetative disorders. Conclusions. Syndrome revealed the presence of vegetative-vascular dysfunction in patients with rosacea with a predominance of parasympathetic tone of the autonomic nervous system. Severity of psychoemotional disorders had no direct relationship to the severity of rosacea. But patients with advanced disease had a tighter self-control on the background of increased excitability and stronger internal emotional stress. Those patients were compared with a group of patients with earlier stage disease, which may provoke functional impairments and in case of long existence-the formation of psychosomatic disorders. This comprehensive assessment of vegetative and emotional status is included in the algorithm for evaluation of patients with rosacea and will successfully complement traditional therapy.

  15. Reliability of Quantitative Ultrasonic Assessment of Normal-Tissue Toxicity in Breast Cancer Radiotherapy

    International Nuclear Information System (INIS)

    Purpose: We have recently reported that ultrasound imaging, together with ultrasound tissue characterization (UTC), can provide quantitative assessment of radiation-induced normal-tissue toxicity. This study’s purpose is to evaluate the reliability of our quantitative ultrasound technology in assessing acute and late normal-tissue toxicity in breast cancer radiotherapy. Method and Materials: Our ultrasound technique analyzes radiofrequency echo signals and provides quantitative measures of dermal, hypodermal, and glandular tissue toxicities. To facilitate easy clinical implementation, we further refined this technique by developing a semiautomatic ultrasound-based toxicity assessment tool (UBTAT). Seventy-two ultrasound studies of 26 patients (720 images) were analyzed. Images of 8 patients were evaluated for acute toxicity (<6 months postradiotherapy) and those of 18 patients were evaluated for late toxicity (≥6 months postradiotherapy). All patients were treated according to a standard radiotherapy protocol. To assess intraobserver reliability, one observer analyzed 720 images in UBTAT and then repeated the analysis 3 months later. To assess interobserver reliability, three observers (two radiation oncologists and one ultrasound expert) each analyzed 720 images in UBTAT. An intraclass correlation coefficient (ICC) was used to evaluate intra- and interobserver reliability. Ultrasound assessment and clinical evaluation were also compared. Results: Intraobserver ICC was 0.89 for dermal toxicity, 0.74 for hypodermal toxicity, and 0.96 for glandular tissue toxicity. Interobserver ICC was 0.78 for dermal toxicity, 0.74 for hypodermal toxicity, and 0.94 for glandular tissue toxicity. Statistical analysis found significant changes in dermal (p < 0.0001), hypodermal (p = 0.0027), and glandular tissue (p < 0.0001) assessments in the acute toxicity group. Ultrasound measurements correlated with clinical Radiation Therapy Oncology Group (RTOG) toxicity scores of patients

  16. Microtox Toxicity Assay for the Sediment Quality Assessment of Ganga River

    Directory of Open Access Journals (Sweden)

    K. R. Beg

    2008-01-01

    Full Text Available The objective of this study was to determine the sediment quality assessment of Ganga River at Kanpur city where effluents from tannery industries are discharged. Sediment samples from control, upstream and downstream area were collected and analyzed for bacterial toxicity bioassay along with a reference sediment (LGC6137. The control samples collected from the point of origin of Ganga River at Deoparyag were found non toxic to the bacteria and served as negative controls for the test method. The EC50 of upstream sediment sample were >10,000 mg L-1 sediment (>1% and categorized as non toxic according to toxicity classification. The down stream sediment samples were very toxic to the bacteria and average EC50 value was 4,266 mg L-1 (0.43 % that falls in very toxic category. The downstream sediment and reference sediment were toxic but the later was 10-fold more toxic. It is indicated in our study that the Microtox SPT assay can differentiate between toxic and non-toxic samples over a wide range of toxicity. The present study demonstrated the efficiency of the Microtox SPT assay in the sediment quality assessment and confirms the existing pollution in Ganga River contributed by tannery industries.

  17. Concentrations of potentially toxic elements in soils and vegetables from the macroregion of São Paulo, Brazil: availability for plant uptake.

    Science.gov (United States)

    dos Santos-Araujo, Sabrina Novaes; Alleoni, Luís Reynaldo Ferracciú

    2016-02-01

    The occurrence and accumulation of heavy metals or so-called potentially toxic elements (PTEs) in soils and plants have driven long-standing concerns about the adverse effects such metals have on the environment and human health. Furthermore, contaminated food products are known to be a leading source of exposure to heavy metals for the general population. It is crucial to accurately assess the concentrations of metals in crops and the bioavailable contents of these elements in the soil. The state of São Paulo is the largest consumer market of horticultural products in Brazil with production focused essentially on urban and industrial areas, which greatly increases the degree of exposure to contaminants. The objective of the authors in this study was to evaluate the soil-plant relationships between concentrations of Cd, Cu, Ni, Pb and Zn in vegetable and garden soils in the state of São Paulo, Brazil. To accomplish this, 200 soil (0-20 cm) and plant samples were collected from 25 species in the production areas. With the exception of Cd, there was positive correlation between pseudototals (USEPA 3051a) and bioavailable contents (extracted with DTPA) of heavy metals. However, the Cd and Pb contents in plants were not significantly correlated with any of the variables studied. All random forest and tree models proved to be good predictors of results generated from a regression model and provided useful information including covariates that were important for specifically forecasting Zn concentration in plants.

  18. Concentrations of potentially toxic elements in soils and vegetables from the macroregion of São Paulo, Brazil: availability for plant uptake.

    Science.gov (United States)

    dos Santos-Araujo, Sabrina Novaes; Alleoni, Luís Reynaldo Ferracciú

    2016-02-01

    The occurrence and accumulation of heavy metals or so-called potentially toxic elements (PTEs) in soils and plants have driven long-standing concerns about the adverse effects such metals have on the environment and human health. Furthermore, contaminated food products are known to be a leading source of exposure to heavy metals for the general population. It is crucial to accurately assess the concentrations of metals in crops and the bioavailable contents of these elements in the soil. The state of São Paulo is the largest consumer market of horticultural products in Brazil with production focused essentially on urban and industrial areas, which greatly increases the degree of exposure to contaminants. The objective of the authors in this study was to evaluate the soil-plant relationships between concentrations of Cd, Cu, Ni, Pb and Zn in vegetable and garden soils in the state of São Paulo, Brazil. To accomplish this, 200 soil (0-20 cm) and plant samples were collected from 25 species in the production areas. With the exception of Cd, there was positive correlation between pseudototals (USEPA 3051a) and bioavailable contents (extracted with DTPA) of heavy metals. However, the Cd and Pb contents in plants were not significantly correlated with any of the variables studied. All random forest and tree models proved to be good predictors of results generated from a regression model and provided useful information including covariates that were important for specifically forecasting Zn concentration in plants. PMID:26780411

  19. Plant bioassays to assess toxicity of textile sludge compost

    OpenAIRE

    Araújo Ademir Sérgio Ferreira de; Monteiro Regina Teresa Rosim

    2005-01-01

    Composting of industrial wastes is increasing because of recycling requirements set on organic wastes. The evaluation of toxicity of these wastes by biological testing is therefore extremely important for screening the suitability of waste for land application. The toxicity of a textile sludge compost was investigated using seed germination and plant growth bioassays using soybean and wheat. Compost samples were mixed with water (seed germination bioassay) or nutrient solution (plant growth b...

  20. Assessing environmental impacts of constructed wetland effluents for vegetable crop irrigation.

    Science.gov (United States)

    Castorina, A; Consoli, S; Barbagallo, S; Branca, F; Farag, A; Licciardello, F; Cirelli, G L

    2016-01-01

    The objective of this study was to monitor and assess environmental impacts of reclaimed wastewater (RW), used for irrigation of vegetable crops, on soil, crop quality and irrigation equipment. During 2013, effluents of a horizontal sub-surface flow constructed treatment wetland (TW) system, used for tertiary treatment of sanitary wastewater from a small rural municipality located in Eastern Sicily (Italy), were reused by micro-irrigation techniques to irrigate vegetable crops. Monitoring programs, based on in situ and laboratory analyses were performed for assessing possible adverse effects on water-soil-plant systems caused by reclaimed wastewater reuse. In particular, experimental results evidenced that Escherichia coli content found in RW would not present a risk for rotavirus infection following WHO (2006) standards. Irrigated soil was characterized by a certain persistence of microbial contamination and among the studied vegetable crops, lettuce responds better, than zucchini and eggplants, to the irrigation with low quality water, evidencing a bettering of nutraceutical properties and production parameters.

  1. Integrating the fish embryo toxicity test as triad element for sediment toxicity assessment based on the water framework directive approach

    Energy Technology Data Exchange (ETDEWEB)

    Bartzke, Mariana [Dept. Aquatic Ecotoxicology, Goethe Univ. Frankfurt am Main (Germany); Gobio GmbH, Aarbergen/Kettenbach (Germany); Dept. Bioanalytical Ecotoxicology, Helmholtz Centre for Environmental Research, UFZ, Leipzig (Germany); Delov, Vera [Dept. Aquatic Ecotoxicology, Goethe Univ. Frankfurt am Main (Germany); Gobio GmbH, Aarbergen/Kettenbach (Germany); Ecotoxicology, Fraunhofer Inst. for Molecular Biology and Applied Ecology IME, Aachen (Germany); Stahlschmidt-Allner, Petra; Allner, Bernhard [Gobio GmbH, Aarbergen/Kettenbach (Germany); Oehlmann, Joerg [Dept. Aquatic Ecotoxicology, Goethe Univ. Frankfurt am Main (Germany)

    2010-04-15

    Purpose: The objective of this study was to complement analyses according to the European Union Water Framework Directive (WFD) with a sediment toxicity analysis as part of an integrated river assessment. To this end, Hessian water courses were analyzed using the sediment quality triad concept according to Chapman with chemical analyses, in situ effect evaluations, and ecotoxicological assessments. For the ecotoxicological assessment (fish embryo toxicity test with Danio rerio), a new evaluation scheme was developed, the fish teratogenicity index (FTI), that allows for a classification of sediments into ecological quality classes compliant to the WFD. Materials and methods sediment and macrozoobenthos samples were taken from tributaries of the rivers Fulda and Lahn. Sediments were characterized regarding particle size, carbon, heavy metals, and polyaromatic hydrocarbon content. Macroinvertebrate samples were taken via multi-habitat sampling. The fish embryo toxicity test with D. rerio was conducted as a contact assay on the basis of DIN 38415-6. Results and discussion The integrated assessment indicated a significant influence of heavy metals and carbon content on macroinvertebrate communities. The bioaccessibility of sediment pollutants were clearly demonstrated by the FTI, which showed a wide range of adverse effects. A significant linear relationship between metals and the FTI was detected. However, there was no statistically significant evidence that macroinvertebrate communities were affected by the hydromorphological quality clements at the sampling sites. Conclusions The new scheme for the assessment of fish embryo toxicity test was successfully applied. The results suggest that sediment compounds impact macroinvertebrate communities and early development of fish. It demonstrates that the quality of sediments should be evaluated on a routine basis as part of an integrated river assessment. (orig.)

  2. Assessing risk to human health from tropical leafy vegetables grown on contaminated urban soils

    International Nuclear Information System (INIS)

    Fifteen tropical leafy vegetable types were sampled from farmers' gardens situated on nine contaminated sites used to grow vegetables for commercial or subsistence consumption in and around Kampala City, Uganda. Trace metal concentrations in soils were highly variable and originated from irrigation with wastewater, effluent discharge from industry and dumping of solid waste. Metal concentrations in the edible shoots of vegetables also differed greatly between, and within, sites. Gynandropsis gynandra consistently accumulated the highest Cd, Pb and Cu concentrations, while Amaranthus dubius accumulated the highest Zn concentration. Cadmium uptake from soils with contrasting sources and severity of contamination was consistently lowest in Cucurbita maxima and Vigna unguiculata, suggesting these species were most able to restrict Cd uptake from contaminated soil. Concentrations of Pb and Cr were consistently greater in unwashed, than in washed, vegetables, in marked contrast to Cd, Ni and Zn. The risk to human health, expressed as a 'hazard quotient' (HQM), was generally greatest for Cd, followed successively by Pb, Zn, Ni and Cu. Nevertheless, it was apparent that urban cultivation of leafy vegetables could be safely pursued on most sites, subject to site-specific assessment of soil metal burden, judicious choice of vegetable types and adoption of washing in clean water prior to cooking.

  3. Assessing risk to human health from tropical leafy vegetables grown on contaminated urban soils

    Energy Technology Data Exchange (ETDEWEB)

    Nabulo, G.; Young, S.D.; Black, C.R., E-mail: colin.black@nottingham.ac.uk [School of Biosciences, University of Nottingham, Nottingham, NG7 2RD (United Kingdom)

    2010-10-15

    Fifteen tropical leafy vegetable types were sampled from farmers' gardens situated on nine contaminated sites used to grow vegetables for commercial or subsistence consumption in and around Kampala City, Uganda. Trace metal concentrations in soils were highly variable and originated from irrigation with wastewater, effluent discharge from industry and dumping of solid waste. Metal concentrations in the edible shoots of vegetables also differed greatly between, and within, sites. Gynandropsis gynandra consistently accumulated the highest Cd, Pb and Cu concentrations, while Amaranthus dubius accumulated the highest Zn concentration. Cadmium uptake from soils with contrasting sources and severity of contamination was consistently lowest in Cucurbita maxima and Vigna unguiculata, suggesting these species were most able to restrict Cd uptake from contaminated soil. Concentrations of Pb and Cr were consistently greater in unwashed, than in washed, vegetables, in marked contrast to Cd, Ni and Zn. The risk to human health, expressed as a 'hazard quotient' (HQ{sub M}), was generally greatest for Cd, followed successively by Pb, Zn, Ni and Cu. Nevertheless, it was apparent that urban cultivation of leafy vegetables could be safely pursued on most sites, subject to site-specific assessment of soil metal burden, judicious choice of vegetable types and adoption of washing in clean water prior to cooking.

  4. Assessment of vegetation and naturalness: a study case in Southern Italy

    Directory of Open Access Journals (Sweden)

    De Simone L

    2008-07-01

    Full Text Available The study of vegetation and naturalness in the province of Benevento (southern Italy was conducted through a series of complementary steps starting from a preliminary phase of bibliographical research. To draw up the theme map, after the preparatory phase of GIS-based cartographic support, a photo-interpretation phase was conducted for the whole province of Benevento on the basis of orthophotos at a scale of 1:10.000 taken in 1997-1998 supplied by the Provincial Authority. We produced a map which chiefly takes account of the physiognomic features of vegetation alongside floristic data. Throughout the province of Benevento we identified 21 main floristic types grouped into four categories, which include three physiognomic categories and one category grouping the areas greatly affected by human impact. For each vegetation type we calculated the percentage of the area against the whole surface area of the province. Starting from the vegetation map, the vegetation types in the area were reclassified according to the scale of naturalness ordered according to the criterion of proximity to the mature vegetation phase. The conservation status of the plant landscape in the province of Benevento was thus assessed by using the ILC (Index of Landscape Conservation.

  5. Toxicity Assessment of Sediments with Natural Anomalous Concentrations in Heavy Metals by the Use of Bioassay

    Directory of Open Access Journals (Sweden)

    Francisco Martín

    2010-01-01

    Full Text Available The potential toxicity in riverbed sediments was assessed with a bioassay using the bioluminescent bacteria Vibrio fischeri. The selected area was characterized by the presence of ultramafic rocks (peridotites, and the sediments had high values in Ni, Cr, and Co. For the toxicity bioassay with Vibrio fischeri, water-soluble forms were used. The results indicated that most of the samples had a very low degree of toxicity, with 10% of reduction in luminescence in relation to the control; meanwhile 25% of the samples had a moderate degree of toxicity with a reduction in luminescence between 13 and 21% in relation to the control. The toxicity index correlated significantly with the concentrations of Ni and Cr in the water extracts. This toxicity bioassay was proved to be a sensitive and useful tool to detect potential toxicity in solutions, even with anomalous concentrations in heavy metals of natural origin.

  6. Distribution and Risk Assessment of Polycyclic Aromatic Hydrocarbons in Vegetables Grown in Pakistan

    Directory of Open Access Journals (Sweden)

    Mohammad W. Ashraf

    2013-01-01

    Full Text Available Distribution and risk assessment of eight priority polycyclic aromatic hydrocarbons (PAHs contents have been examined in different varieties of vegetables grown in Pakistan. The results showed that the total PAH contents were higher for root vegetables like potato and carrot (~13 μg/kg and relatively lower for turnip (10.9 μg/kg, respectively while for the fruit vegetables, all the peels were found to be more contaminated than cores. The ratio of total PAH concentrations in peels with respect to those of cores is found to be 1.45, 1.26, 1.31, 1.44, 1.40, and 1.36 for potato, turnip, carrot, eggplant, cucumber, and bitter gourd, respectively. For leafy vegetables, cabbage showed maximum PAH (11.6 μg/kg as compared to the cores of fruit vegetables. Among individual PAH congeners, anthracene showed higher levels in all vegetables. For benzo(aanthracene, maximum concentration (3.44±2.10 μg/kg was encountered in turnip cores. Highest benzo(epyrene concentration was found in potato (3.19±1.67 μg/kg followed by turnip (2.74±1.22 μg/kg. Benzo(bfluoranthene and benzo(kfluoranthene showed relatively lower levels in all samples studied. All the concentrations of PAHs are presented on a fresh weight basis. The results of human exposure of PAH by consumption of these vegetables showed that cumulative dietary exposure of Pakistani population to PAHs from vegetables ranges from 0.25 μg/p/d to 1.16 μg/p/d.

  7. Risk assessment of N-nitrosodimethylamine formed endogenously after fish-with-vegetable meals

    NARCIS (Netherlands)

    Zeilmaker, M.J.; Bakker, M.I.; Schothorst, R.; Slob, W.

    2010-01-01

    The consumption of fish and nitrate-rich vegetables may lead to the formation of the genotoxic carcinogen N-nitrosodimethylamine (NDMA) in the stomach. To assess human cancer risk associated with this formation, a dynamic in vitro gastrointestinal model was used to simulate NDMA formation in the sto

  8. Assessment of acrylamide toxicity using a battery of standardised bioassays.

    Science.gov (United States)

    Zovko, Mira; Vidaković-Cifrek, Željka; Cvetković, Želimira; Bošnir, Jasna; Šikić, Sandra

    2015-12-01

    Acrylamide is a monomer widely used as an intermediate in the production of organic chemicals, e.g. polyacrylamides (PAMs). Since PAMs are low cost chemicals with applications in various industries and waste- and drinking water treatment, a certain amount of non-polymerised acrylamide is expected to end up in waterways. PAMs are non-toxic but acrylamide induces neurotoxic effects in humans and genotoxic, reproductive, and carcinogenic effects in laboratory animals. In order to evaluate the effect of acrylamide on freshwater organisms, bioassays were conducted on four species: algae Desmodesmus subspicatus and Pseudokirchneriella subcapitata, duckweed Lemna minor and water flea Daphnia magna according to ISO (International Organization for Standardisation) standardised methods. This approach ensures the evaluation of acrylamide toxicity on organisms with different levels of organisation and the comparability of results, and it examines the value of using a battery of low-cost standardised bioassays in the monitoring of pollution and contamination of aquatic ecosystems. These results showed that EC50 values were lower for Desmodesmus subspicatus and Pseudokirchneriella subcapitata than for Daphnia magna and Lemna minor, which suggests an increased sensitivity of algae to acrylamide. According to the toxic unit approach, the values estimated by the Lemna minor and Daphnia magna bioassays, classify acrylamide as slightly toxic (TU=0-1; Class 1). The results obtained from algal bioassays (Desmodesmus subspicatus and Pseudokirchneriella subcapitata) revealed the toxic effect of acrylamide (TU=1-10; Class 2) on these organisms.

  9. Assessment of acrylamide toxicity using a battery of standardised bioassays.

    Science.gov (United States)

    Zovko, Mira; Vidaković-Cifrek, Željka; Cvetković, Želimira; Bošnir, Jasna; Šikić, Sandra

    2015-12-01

    Acrylamide is a monomer widely used as an intermediate in the production of organic chemicals, e.g. polyacrylamides (PAMs). Since PAMs are low cost chemicals with applications in various industries and waste- and drinking water treatment, a certain amount of non-polymerised acrylamide is expected to end up in waterways. PAMs are non-toxic but acrylamide induces neurotoxic effects in humans and genotoxic, reproductive, and carcinogenic effects in laboratory animals. In order to evaluate the effect of acrylamide on freshwater organisms, bioassays were conducted on four species: algae Desmodesmus subspicatus and Pseudokirchneriella subcapitata, duckweed Lemna minor and water flea Daphnia magna according to ISO (International Organization for Standardisation) standardised methods. This approach ensures the evaluation of acrylamide toxicity on organisms with different levels of organisation and the comparability of results, and it examines the value of using a battery of low-cost standardised bioassays in the monitoring of pollution and contamination of aquatic ecosystems. These results showed that EC50 values were lower for Desmodesmus subspicatus and Pseudokirchneriella subcapitata than for Daphnia magna and Lemna minor, which suggests an increased sensitivity of algae to acrylamide. According to the toxic unit approach, the values estimated by the Lemna minor and Daphnia magna bioassays, classify acrylamide as slightly toxic (TU=0-1; Class 1). The results obtained from algal bioassays (Desmodesmus subspicatus and Pseudokirchneriella subcapitata) revealed the toxic effect of acrylamide (TU=1-10; Class 2) on these organisms. PMID:26751864

  10. Pesticide residues in leafy vegetables, stalk and stem vegetables from South Korea: a long-term study on safety and health risk assessment.

    Science.gov (United States)

    Park, Duck Woong; Kim, Kwang Gon; Choi, Eun Ah; Kang, Gyeong Ri; Kim, Tae Sun; Yang, Yong Shik; Moon, Su Jin; Ha, Dong Ryong; Kim, Eun Sun; Cho, Bae Sik

    2016-01-01

    South Korea has a unique food culture. South Koreans enjoy wrapping meat and eating or making kimchi (traditionally fermented Korean food) and eating using raw leafy vegetables, stalk and stem vegetables. Therefore, there is a high chance of being exposed to pesticide residues of vegetables. The objective of this study was to investigate pesticide residues in leafy vegetables, stalk and stem vegetables from South Korea. A total of 8496 samples were mainly collected from Gwangju and Jeonnam area (the largest production region of leafy vegetables, stalk and stem vegetables) in South Korea from 2010 to 2014. A total of 230 pesticides were used for multi-residue analysis of pesticides. Among 8496 samples, 61 different pesticides (1029 times) were detected in 890 samples, of which 118 samples (1.4%) exceeded the Korea maximum residue limits (MRLs). Samples exceeding the MRLs were mostly found in leafy vegetables (brassica lee ssp. namai, leafy lettuce, spinach, perilla leaves, crown daisy, marsh mallow, aster scaber, pimpinella brachycarpa) and Chinese chive. Procymidone, dimethomorph and azoxystrobin were the most frequently found pesticides. A risk assessment of pesticides exceeding the MRLs was evaluated by calculating the estimated daily intake (EDI) and the acceptable daily intake (ADI). The ratio of EDI to ADI was 0.003-30.4%. PMID:26571090

  11. Pesticide residues in leafy vegetables, stalk and stem vegetables from South Korea: a long-term study on safety and health risk assessment.

    Science.gov (United States)

    Park, Duck Woong; Kim, Kwang Gon; Choi, Eun Ah; Kang, Gyeong Ri; Kim, Tae Sun; Yang, Yong Shik; Moon, Su Jin; Ha, Dong Ryong; Kim, Eun Sun; Cho, Bae Sik

    2016-01-01

    South Korea has a unique food culture. South Koreans enjoy wrapping meat and eating or making kimchi (traditionally fermented Korean food) and eating using raw leafy vegetables, stalk and stem vegetables. Therefore, there is a high chance of being exposed to pesticide residues of vegetables. The objective of this study was to investigate pesticide residues in leafy vegetables, stalk and stem vegetables from South Korea. A total of 8496 samples were mainly collected from Gwangju and Jeonnam area (the largest production region of leafy vegetables, stalk and stem vegetables) in South Korea from 2010 to 2014. A total of 230 pesticides were used for multi-residue analysis of pesticides. Among 8496 samples, 61 different pesticides (1029 times) were detected in 890 samples, of which 118 samples (1.4%) exceeded the Korea maximum residue limits (MRLs). Samples exceeding the MRLs were mostly found in leafy vegetables (brassica lee ssp. namai, leafy lettuce, spinach, perilla leaves, crown daisy, marsh mallow, aster scaber, pimpinella brachycarpa) and Chinese chive. Procymidone, dimethomorph and azoxystrobin were the most frequently found pesticides. A risk assessment of pesticides exceeding the MRLs was evaluated by calculating the estimated daily intake (EDI) and the acceptable daily intake (ADI). The ratio of EDI to ADI was 0.003-30.4%.

  12. On the use of mixture toxicity assessment in REACH and the water framework directive

    DEFF Research Database (Denmark)

    Syberg, Kristian; Jensen, T.S.; Cedergreen, Nina;

    2009-01-01

      This review seeks to connect the scientific theory of mixture toxicity to its implementation within different regulatory frameworks. The aim is to demonstrate how mixture toxicity assessment can be more thoroughly integrated into the European chemical regulations, REACH and the Water Framework...... Directive (WFD), using the experiences gained through other regulatory frameworks. The paper consists of 1) an examination of the scientific underpinnings of the common mixture toxicity assessment methods; 2) a discussion of how these methods have been used in regulatory frameworks; and 3) a discussion...... that it is scientifically feasible and regulatory practicable to integrate a more holistic mixture toxicity approach into both legislations. In this connection, the experience gained from the US frameworks on mixture toxicity assessment could be useful. The construction of a database that includes data on chemicals...

  13. Toxic Assessment of Triclosan and Triclocarban on Artemia salina.

    Science.gov (United States)

    Xu, Xiaolu; Lu, Yin; Zhang, Deyong; Wang, Yinyin; Zhou, Xianshan; Xu, Huiying; Mei, Yu

    2015-12-01

    In this study, we investigated the possible acute toxic and genotoxic effects of triclosan (TCS) and triclocarban (TCC) on Artemia salina. Genotoxicity was evaluated using single-cell gel electrophoresis and apoptotic frequency assays (Annexin V-FITC/PI assay). Acute toxicity test results showed that TCC (LC50-24 h = 17.8 µg/L) was more toxic than TCS (LC50-24 h = 171.1 µg/L). Significant increases in both genotoxic biomarkers were observed at 24 h after initial exposure, indicating that these two chemicals are potentially dangerous for this aquatic biological model. Although further studies are required, a comparison of data both in vitro and in vivo allowed us to suggest possible mechanisms of action for TCS and TCC in this sentinel organism. PMID:26310128

  14. EPR as an analytical tool in assessing the mineral nutrients and irradiated food products-vegetables

    Science.gov (United States)

    Prasuna, C. P. Lakshmi; Chakradhar, R. P. S.; Rao, J. L.; Gopal, N. O.

    2008-12-01

    EPR spectral investigations of some commonly available vegetables in south India, which are of global importance like Daucus carota (carrot), Cyamopsis tetragonoloba (cluster beans), Coccinia indica (little gourd) and Beta vulgaris (beet root) have been carried out. In all the vegetable samples a free radical corresponding to cellulose radical is observed. Almost all the samples under investigation exhibit Mn ions in different oxidation states. The temperature variation EPR studies are done and are discussed in view of the paramagnetic oxidation states. The radiation-induced defects have also been assessed by using the EPR spectra of such irradiated food products.

  15. 78 FR 14510 - Notice of Availability of New Guidelines for Pest Risk Assessments of Imported Fruits and Vegetables

    Science.gov (United States)

    2013-03-06

    ... Animal and Plant Health Inspection Service Notice of Availability of New Guidelines for Pest Risk Assessments of Imported Fruits and Vegetables AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION... health pest risk assessments for imported fruit and vegetable commodities. These new guidelines...

  16. Hazard identification and characterisation, and dose response assessment of spore forming pathogens in cooked chilled food containing vegetables

    NARCIS (Netherlands)

    Leusden FM van; MGB

    2001-01-01

    A hazard identification and characterisation, including a preliminary dose response assessment, of sporeforming pathogens in cooked chilled food containing vegetables was performed according to the structure and principles for a quantitative microbiological risk assessment as described by the Codex

  17. Vegetation Classification, Ecological Integrity Assessment (EIA), Climate Change Vulnerability Assessment at Camas National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project includes a pilot study to map the vegetation of Camas National Wildlife Refuge and a report on the overall ecological integrity of the refuge, how it...

  18. Vegetation assessment in a pipeline influence area: the case study of PETROBRAS ammonia pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Basbaum, Marcos A.; Porciano, Patricia P.; Bonafini, Fabio L. [SEEBLA - Servicos de Engenharia Emilio Baumgart Ltda., Rio de Janeiro, RJ (Brazil)], e-mail: mbasbaum.seebla@petrobras.com.br, e-mail: patriciapp.seebla@petrobras.com.br, e-mail: bonafini.seebla@petrobras.com.br; Guimaraes, Ricardo Z.P.; Torggler, Bianca F.; Fernandes, Renato; Vieira, Elisa D.R. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)], e-mail: rzaluar@petrobras.com.br, e-mail: torggler@petrobras.com.br, e-mail: renatofer@petrobras.com.br, e-mail: elisav@petrobras.com.br

    2009-12-19

    This ammonia pipeline is about 30 km long and links the Fertilizer Plant (FAFEN-BA) to the Urea Marine Terminal (TMU) at the Port of Aratu in Candeias (Bahia State, Brazil). In this study, we characterize the remnants of vegetation and quantify the Permanent Preservation Areas. Furthermore, we propose areas and techniques for their recovery and / or management. The methodology was based on the Rapid Ecological Assessment, which combines selection of areas through remote sensing image analysis, with rapid field campaigns in the selected points. This methodology, successfully applied in PETROBRAS refineries, is first applied in a pipeline influence area. During these campaigns, the main aspects of vegetation, such as phyto physiognomy and ecological succession stages, were registered in field data sheets prepared for this purpose. The most representative remnants of vegetation that could be quantified were Atlantic Forest fragments, as well as those in the Permanent Preservation Areas. (author)

  19. Assessment of parasitic contamination of raw vegetables in Mannuthy, Kerala state, India

    Directory of Open Access Journals (Sweden)

    B. Sunil

    2014-04-01

    Full Text Available Aim: To assess the parasitic contamination of raw vegetables retailed at Mannuthy in Thrissur district of Kerala state, India. Materials and Methods: A total of 112 samples, viz. cabbage (17, mint (11, coriander leaves (11, spinach (15, onion (10, carrot (10, potato (10, ginger (15, beet root (7 and tomato (6 were collected from retail market at Mannuthy, Kerala. Collected samples were washed with physiological saline solution. The washings were collected and examined under light microscopy. Results: Helminthic eggs were detected in three (2.7% of 112 samples. Two samples of cabbage (1.8% and one sample of onion (0.9% was positive for ova of Ascaris spp. Conclusion: Vegetables can act as potential source of gastrointestinal parasitic infections. The study emphasizes the need for proper washing of vegetables before they are consumed or cooked.

  20. Assessment of the In Vivo Toxicity of Gold Nanoparticles

    Science.gov (United States)

    Chen, Yu-Shiun; Hung, Yao-Ching; Liau, Ian; Huang, G. Steve

    2009-08-01

    The environmental impact of nanoparticles is evident; however, their toxicity due to their nanosize is rarely discussed. Gold nanoparticles (GNPs) may serve as a promising model to address the size-dependent biological response to nanoparticles because they show good biocompatibility and their size can be controlled with great precision during their chemical synthesis. Naked GNPs ranging from 3 to 100 nm were injected intraperitoneally into BALB/C mice at a dose of 8 mg/kg/week. GNPs of 3, 5, 50, and 100 nm did not show harmful effects; however, GNPs ranging from 8 to 37 nm induced severe sickness in mice. Mice injected with GNPs in this range showed fatigue, loss of appetite, change of fur color, and weight loss. Starting from day 14, mice in this group exhibited a camel-like back and crooked spine. The majority of mice in these groups died within 21 days. Injection of 5 and 3 nm GNPs, however, did not induce sickness or lethality in mice. Pathological examination of the major organs of the mice in the diseased groups indicated an increase of Kupffer cells in the liver, loss of structural integrity in the lungs, and diffusion of white pulp in the spleen. The pathological abnormality was associated with the presence of gold particles at the diseased sites, which were verified by ex vivo Coherent anti-Stoke Raman scattering microscopy. Modifying the surface of the GNPs by incorporating immunogenic peptides ameliorated their toxicity. This reduction in the toxicity is associated with an increase in the ability to induce antibody response. The toxicity of GNPs may be a fundamental determinant of the environmental toxicity of nanoparticles.

  1. Assessment of the In Vivo Toxicity of Gold Nanoparticles

    Directory of Open Access Journals (Sweden)

    Liau Ian

    2009-01-01

    Full Text Available Abstract The environmental impact of nanoparticles is evident; however, their toxicity due to their nanosize is rarely discussed. Gold nanoparticles (GNPs may serve as a promising model to address the size-dependent biological response to nanoparticles because they show good biocompatibility and their size can be controlled with great precision during their chemical synthesis. Naked GNPs ranging from 3 to 100 nm were injected intraperitoneally into BALB/C mice at a dose of 8 mg/kg/week. GNPs of 3, 5, 50, and 100 nm did not show harmful effects; however, GNPs ranging from 8 to 37 nm induced severe sickness in mice. Mice injected with GNPs in this range showed fatigue, loss of appetite, change of fur color, and weight loss. Starting from day 14, mice in this group exhibited a camel-like back and crooked spine. The majority of mice in these groups died within 21 days. Injection of 5 and 3 nm GNPs, however, did not induce sickness or lethality in mice. Pathological examination of the major organs of the mice in the diseased groups indicated an increase of Kupffer cells in the liver, loss of structural integrity in the lungs, and diffusion of white pulp in the spleen. The pathological abnormality was associated with the presence of gold particles at the diseased sites, which were verified by ex vivo Coherent anti-Stoke Raman scattering microscopy. Modifying the surface of the GNPs by incorporating immunogenic peptides ameliorated their toxicity. This reduction in the toxicity is associated with an increase in the ability to induce antibody response. The toxicity of GNPs may be a fundamental determinant of the environmental toxicity of nanoparticles.

  2. Assessment of the environmental effects of mining using SPOT-Vegetation NDVI

    Science.gov (United States)

    Tote, C.; Swinnen, E.; Goossens, M.; Reusen, I.; Delalieux, S.

    2012-04-01

    Within the ImpactMin project, funded by the Framework Programme 7 of the European Commission, new methods for the environmental impact monitoring of mining operations are being developed. The objective of this study is to analyze the impact of mining on soil properties through assessment of the vegetation status using time series analysis of low resolution Normalized Difference Vegetation Index (NDVI) images derived from SPOT-Vegetation. The study focuses on the surroundings of mining areas in the Orenburg region in the Russian Urals. Karabash has been a centre for mining and metal production for well over 3000 years, and environmental impact of (historical) mining in the area is extremely severe. The area was characterized as an 'ecological disaster zone', based on chemical analysis of soil samples in the area [1]. The mining activities were intensified in the early to mid-20th century, but the old smelter was modernized in the 1990s. A time series of 10-daily NDVI images from SPOT-Vegetation (S10 April/1998-December/2010 at 1km2 resolution, http://www.vgt.vito.be/) is analyzed. Different land cover types clearly show different phenology. To remove seasonal vegetation changes and thus to facilitate the interpretation through the historical record, a Standardized Difference Vegetation Index (SDVI) was calculated for each pixel and for each record of the time series. The first results of trend analyses indicate a strong recovery of open forests in the Karabash region in the last decade. To what extent this can be related to reduced mining impact or climate factors, still needs to be assessed. Further research will also focus on the spatial heterogeneity of phenological parameters, in relation to distance to and wind direction of the smelters and soil properties. [1] V. Nestersnko, "Urban associations of elements- environmental pollutants in Karabash city (Chelyabinsk oblast) as a reflection of ore-chemical descriptions of mineral raw material", Proceedings of the

  3. Examination of in vivo influences on bioluminescent microbial assessment of corrosion product toxicity.

    Science.gov (United States)

    Shettlemore, M G; Bundy, K J

    2001-08-01

    The composition of ionically dissolved and precipitated corrosion products from both free corrosion of ASTM F75 Co-Cr-Mo and galvanostatic polarization of Co-Cr-Mo and F138 316L stainless steel was determined using differential pulse polarography and inductively coupled plasma atomic emission spectroscopy. A bacterial bioluminescence assay, Microtox, was used to assess the toxicity of the solid and dissolved corrosion products produced by galvanostatic polarization and the individual ions within them. The role of in vivo salinity, temperature, and protein content as modulators of corrosion product toxicity assessment was investigated empirically and mechanistically. Co-Cr-Mo products were found to be more toxic than those of 316L, and the most toxic ions were Cr6+, Ni2+, and Co2+. Ringer's solution potentiated the toxicity of the more toxic metal ions and reduced the toxicity of the less toxic ions. Using theoretical analysis in conjunction with experimental measurements, the ions in both alloys were found to interact in an antagonistic fashion. The presence of albumin was found to decrease metal toxicity, presumably by chelation. PMID:11456061

  4. Modified Whole Effluent Toxicity Test to Assess and Decouple Wastewater Effects from Environmental Gradients

    OpenAIRE

    Sebastián Sauco; Julio Gómez; Francisco R Barboza; Diego Lercari; Omar Defeo

    2013-01-01

    Environmental gradients and wastewater discharges produce aggregated effects on marine populations, obscuring the detection of human impact. Classical assessment methods do not include environmental effects in toxicity tests designs, which could lead to incorrect conclusions. We proposed a modified Whole Effluent Toxicity test (mWET) that includes environmental gradients in addition to effluent dilutions, together with the application of Generalized Linear Mixed Models (GLMM) to assess and de...

  5. Assessment of hydrogen fluoride damage to vegetation using optical remote sensing data

    Science.gov (United States)

    Hyun, C. U.; Lee, J. S.; Lee, I.

    2013-10-01

    This research assesses damage to vegetation from accidental gaseous hydrogen fluoride leakage, through the analysis of spectral features of the damaged plants using digital aerial photographs and airborne hyperspectral imagery. The hyperspectral imagery was obtained 21 days after the leakage within visible and near-infrared wavelength range using CASI-1500 imager, and two aerial photographs composed of blue, green, red and near-infrared bands were also obtained in 2 October 2011 and 15 November 2012, respectively. The injuries on leaves and the outline of the leakage affected area were assessed by investigating vegetation index images calculated from the hyperspectral imagery and the aerial photograph obtained in 15 November 2012, with comparison to the index image calculated from the aerial photograph obtained in 12 October 2011. The affected areas were mainly distributed in the east of the leakage point, and this reflects predominant wind directions toward east during the leakage and within 24 hours after the leakage. In addition, the detailed changes in spectral reflectance curves of damaged vegetation were also investigated using the hyperspectral imagery. Paddy field and forest land were identified by cadastral map, and the reference areas for the comparison of the reflectance curve change were designated to each land cover type, by considering the most and least affected areas from the vegetation indices comparison results.

  6. Using Unmanned Aerial Vehicles to Assess Vegetative Cover in Sagebrush Steppe Ecosytstems

    Energy Technology Data Exchange (ETDEWEB)

    Robert P. Breckenridge

    2005-09-01

    The Idaho National Laboratory (INL), in conjunction with the University of Idaho, is evaluating novel approaches for using unmanned aerial vehicles (UAVs) as a quicker and safer method for monitoring biotic resources. Evaluating vegetative cover is an important factor in understanding the sustainability of many ecosystems. In assessing vegetative cover, methods that improve accuracy and cost efficiency could revolutionize how biotic resources are monitored on western federal lands. Sagebrush steppe ecosystems provide important habitat for a variety of species, some of which are important indicator species (e.g., sage grouse). Improved methods are needed to support monitoring these habitats because there are not enough resource specialists or funds available for comprehensive ground evaluation of these ecosystems. In this project, two types of UAV platforms (fixed wing and helicopter) were used to collect still-frame imagery to assess cover in sagebrush steppe ecosystems. This paper discusses the process for collecting and analyzing imagery from the UAVs to (1) estimate total percent cover, (2) estimate percent cover for six different types of vegetation, and (3) locate sage grouse based on representative decoys. The field plots were located on the INL site west of Idaho Falls, Idaho, in areas with varying amounts and types of vegetative cover. A software program called SamplePoint developed by the U.S. Department of Agriculture, Agricultural Research Service (USDA-ARS) was used to evaluate the imagery for percent cover for the six vegetation types (bare ground, litter, shrubs, dead shrubs, grasses, and forbs). Results were compared against standard field measurements to assess accuracy.

  7. ASSESSMENT OF TOXICITY OF INDUSTRIAL WASTES USING CROP PLANT ASSAYS

    OpenAIRE

    Carmen Alice Teacă; Ruxanda Bodîrlău

    2008-01-01

    Environmental pollution has a harmful action on bioresources, including agricultural crops. It is generated through many industrial activities such as mining, coal burning, chemical technology, cement production, pulp and paper industry, etc. The toxicity of different industrial wastes and heavy metals excess was evaluated using crop plant assays (germination and hydroponics seedlings growth tests). Experimental data regarding the germination process of wheat (from two cultivars) and rye seed...

  8. Assessment of the toxic potential of graphene family nanomaterials

    OpenAIRE

    Xiaoqing Guo; Nan Mei

    2014-01-01

    Graphene, a single-atom-thick carbon nanosheet, has attracted great interest as a promising nanomaterial for a variety of bioapplications because of its extraordinary properties. However, the potential for widespread human exposure raises safety concerns about graphene and its derivatives, referred to as graphene-family nanomaterials. This review summarizes recent findings on the toxicological effects and the potential toxicity mechanisms of graphene-family nanomaterials in bacteria, mammalia...

  9. Toxicity assessment and microbial degradation of azo dyes.

    Science.gov (United States)

    Puvaneswari, N; Muthukrishnan, J; Gunasekaran, P

    2006-08-01

    Toxic effluents containing azo dyes are discharged from various industries and they adversely affect water resources, soil fertility, aquatic organisms and ecosystem integrity. They pose toxicity (lethal effect, genotoxicity, mutagenicity and carcinogenicity) to aquatic organisms (fish, algae, bacteria, etc.) as well as animals. They are not readily degradable under natural conditions and are typically not removed from waste water by conventional waste water treatment systems. Benzidine based dyes have long been recognized as a human urinary bladder carcinogen and tumorigenic in a variety of laboratory animals. Several microorganisms have been found to decolourize, transform and even to completely mineralize azo dyes. A mixed culture of two Pseudomonas strains efficiently degraded mixture of 3-chlorobenzoate (3-CBA) and phenol/cresols. Azoreductases of different microorganisms are useful for the development of biodegradation systems as they catalyze reductive cleavage of azo groups (-N=N-) under mild conditions. In this review, toxic impacts of dyeing factory effluents on plants, fishes, and environment, and plausible bioremediation strategies for removal of azo dyes have been discussed.

  10. Toxicity Assessment of Refill Liquids for Electronic Cigarettes

    Directory of Open Access Journals (Sweden)

    Vincent Varlet

    2015-04-01

    Full Text Available We analyzed 42 models from 14 brands of refill liquids for e-cigarettes for the presence of micro-organisms, diethylene glycol, ethylene glycol, hydrocarbons, ethanol, aldehydes, tobacco-specific nitrosamines, and solvents. All the liquids under scrutiny complied with norms for the absence of yeast, mold, aerobic microbes, Staphylococcus aureus, and Pseudomonas aeruginosa. Diethylene glycol, ethylene glycol and ethanol were detected, but remained within limits authorized for food and pharmaceutical products. Terpenic compounds and aldehydes were found in the products, in particular formaldehyde and acrolein. No sample contained nitrosamines at levels above the limit of detection (1 μg/g. Residual solvents such as 1,3-butadiene, cyclohexane and acetone, to name a few, were found in some products. None of the products under scrutiny were totally exempt of potentially toxic compounds. However, for products other than nicotine, the oral acute toxicity of the e-liquids tested seems to be of minor concern. However, a minority of liquids, especially those with flavorings, showed particularly high ranges of chemicals, causing concerns about their potential toxicity in case of chronic oral exposure.

  11. ASSESSMENT OF TOXICITY OF INDUSTRIAL WASTES USING CROP PLANT ASSAYS

    Directory of Open Access Journals (Sweden)

    Carmen Alice Teacă

    2008-11-01

    Full Text Available Environmental pollution has a harmful action on bioresources, including agricultural crops. It is generated through many industrial activities such as mining, coal burning, chemical technology, cement production, pulp and paper industry, etc. The toxicity of different industrial wastes and heavy metals excess was evaluated using crop plant assays (germination and hydroponics seedlings growth tests. Experimental data regarding the germination process of wheat (from two cultivars and rye seeds in the presence of industrial wastes (thermal power station ash, effluents from a pre-bleaching stage performed on a Kraft cellulose – chlorinated lignin products or chlorolignin, along with use of an excess of some heavy metals (Zn and Cu are presented here. Relative seed germination, relative root elongation, and germination index (a factor of relative seed germination and relative root elongation were determined. Relative root elongation and germination index were more sensitive indicators of toxicity than seed germination. The toxic effects were also evaluated in hydroponics experiments, the sensitivity of three crop plant species, namely Triticum aestivum L. (wheat, Secale cereale (rye, and Zea mays (corn being compared. Physiological aspects, evidenced both by visual observation and biometric measurements (mean root, aerial part and plant length, as well as the cellulose and lignin content were examined.

  12. Evaluation of Chemical Warfare Agent Percutaneous Vapor Toxicity: Derivation of Toxicity Guidelines for Assessing Chemical Protective Ensembles.

    Energy Technology Data Exchange (ETDEWEB)

    Watson, A.P.

    2003-07-24

    Percutaneous vapor toxicity guidelines are provided for assessment and selection of chemical protective ensembles (CPEs) to be used by civilian and military first responders operating in a chemical warfare agent vapor environment. The agents evaluated include the G-series and VX nerve agents, the vesicant sulfur mustard (agent HD) and, to a lesser extent, the vesicant Lewisite (agent L). The focus of this evaluation is percutaneous vapor permeation of CPEs and the resulting skin absorption, as inhalation and ocular exposures are assumed to be largely eliminated through use of SCBA and full-face protective masks. Selection of appropriately protective CPE designs and materials incorporates a variety of test parameters to ensure operability, practicality, and adequacy. One aspect of adequacy assessment should be based on systems tests, which focus on effective protection of the most vulnerable body regions (e.g., the groin area), as identified in this analysis. The toxicity range of agent-specific cumulative exposures (Cts) derived in this analysis can be used as decision guidelines for CPE acceptance, in conjunction with weighting consideration towards more susceptible body regions. This toxicity range is bounded by the percutaneous vapor estimated minimal effect (EME{sub pv}) Ct (as the lower end) and the 1% population threshold effect (ECt{sub 01}) estimate. Assumptions of exposure duration used in CPE certification should consider that each agent-specific percutaneous vapor cumulative exposure Ct for a given endpoint is a constant for exposure durations between 30 min and 2 hours.

  13. Toxicity testing in the 21 century: defining new risk assessment approaches based on perturbation of intracellular toxicity pathways.

    Directory of Open Access Journals (Sweden)

    Sudin Bhattacharya

    Full Text Available The approaches to quantitatively assessing the health risks of chemical exposure have not changed appreciably in the past 50 to 80 years, the focus remaining on high-dose studies that measure adverse outcomes in homogeneous animal populations. This expensive, low-throughput approach relies on conservative extrapolations to relate animal studies to much lower-dose human exposures and is of questionable relevance to predicting risks to humans at their typical low exposures. It makes little use of a mechanistic understanding of the mode of action by which chemicals perturb biological processes in human cells and tissues. An alternative vision, proposed by the U.S. National Research Council (NRC report Toxicity Testing in the 21(st Century: A Vision and a Strategy, called for moving away from traditional high-dose animal studies to an approach based on perturbation of cellular responses using well-designed in vitro assays. Central to this vision are (a "toxicity pathways" (the innate cellular pathways that may be perturbed by chemicals and (b the determination of chemical concentration ranges where those perturbations are likely to be excessive, thereby leading to adverse health effects if present for a prolonged duration in an intact organism. In this paper we briefly review the original NRC report and responses to that report over the past 3 years, and discuss how the change in testing might be achieved in the U.S. and in the European Union (EU. EU initiatives in developing alternatives to animal testing of cosmetic ingredients have run very much in parallel with the NRC report. Moving from current practice to the NRC vision would require using prototype toxicity pathways to develop case studies showing the new vision in action. In this vein, we also discuss how the proposed strategy for toxicity testing might be applied to the toxicity pathways associated with DNA damage and repair.

  14. Assessment of land degradation using time series trend analysis of vegetation indictors in Otindag Sandy land

    International Nuclear Information System (INIS)

    Land condition assessment is a basic prerequisite for finding the degradation of a territory, which might lead to desertification under climatic and human pressures. The temporal change in vegetation productivity is a key indicator of land degradation. In this paper, taking the Otindag Sandy Land as a case, the mean normalized difference vegetation index (NDVIa), net primary production (NPP) and vegetation rain use efficiency (RUE) dynamic trends during 2001–2010 were analysed. The Mann-Kendall test and the Correlation Analysis method were used and their sensitivities to land degradation were evaluated. The results showed that the three vegetation indicators (NDVIa, NPP and RUE) showed a downward trend with the two methods in the past 10 years and the land was degraded. For the analysis of the three vegetation indicators (NDVIa, NPP and RUE), it indicated a decreasing trend in 62.57%, 74.16% and 88.56% of the study area according to the Mann-Kendall test and in 57.85%, 68.38% and 85.29% according to the correlation analysis method. However, the change trends were not significant, the significant trends at the 95% confidence level only accounted for a small proportion. Analysis of NDVIa, NPP and RUE series showed a significant decreasing trend in 9.21%, 4.81% and 6.51% with the Mann-Kendall test. The NPP change trends showed obvious positive link with the precipitation in the study area. While the effect of the inter-annual variation of the precipitation for RUE was small, the vegetation RUE can provide valuable insights into the status of land condition and had best sensitivity to land degradation

  15. Applicability of ambient toxicity testing to national or regional water-quality assessment

    Science.gov (United States)

    Elder, John F.

    1990-01-01

    Comprehensive assessment of the quality of natural waters requires a multifaceted approach. Descriptions of existing conditions may be achieved by various kinds of chemical and hydrologic analyses, whereas information about the effects of such conditions on living organisms depends on biological monitoring. Toxicity testing is one type of biological monitoring that can be used to identify possible effects of toxic contaminants. Based on experimentation designed to monitor responses of organisms to environmental stresses, toxicity testing may have diverse purposes in water-quality assessments. These purposes may include identification of areas that warrant further study because of poor water quality or unusual ecological features, verification of other types of monitoring, or assessment of contaminant effects on aquatic communities. Toxicity-test results are most effective when used as a complement to chemical analyses, hydrologic measurements, and other biological monitoring. However, all toxicity-testing procedures have certain limitations that must be considered in developing the methodology and applications of toxicity testing in any large-scale water-quality-assessment program. A wide variety of toxicity-test methods have been developed to fulfill the needs of diverse applications. The methods differ primarily in the selections made relative to four characteristics: (1) test species, (2) endpoint (acute or chronic), (3) test-enclosure type, and (4) test substance (toxicant) that functions as the environmental stress. Toxicity-test approaches vary in their capacity to meet the needs of large-scale assessments of existing water quality. Ambient testing, whereby the test organism is exposed to naturally occurring substances that contain toxicant mixtures in an organic or inorganic matrix, is more likely to meet these needs than are procedures that call for exposure of the test organisms to known concentrations of a single toxicant. However, meaningful

  16. Comparison of Unmanned Aerial Vehicle Platforms for Assessing Vegetation Cover in Sagebrush Steppe Ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Robert P. Breckenridge; Maxine Dakins; Stephen Bunting; Jerry Harbour; Sera White

    2011-09-01

    In this study, the use of unmanned aerial vehicles (UAVs) as a quick and safe method for monitoring biotic resources was evaluated. Vegetation cover and the amount of bare ground are important factors in understanding the sustainability of many ecosystems and assessment of rangeland health. Methods that improve speed and cost efficiency could greatly improve how biotic resources are monitored on western lands. Sagebrush steppe ecosystems provide important habitat for a variety of species (including sage grouse and pygmy rabbit). Improved methods are needed to support monitoring these habitats because there are not enough resource specialists or funds available for comprehensive ground evaluations. In this project, two UAV platforms, fixed wing and helicopter, were used to collect still-frame imagery to assess vegetation cover in sagebrush steppe ecosystems. This paper discusses the process for collecting and analyzing imagery from the UAVs to (1) estimate percent cover for six different vegetation types (shrub, dead shrub, grass, forb, litter, and bare ground) and (2) locate sage grouse using representative decoys. The field plots were located on the Idaho National Engineering (INL) site west of Idaho Falls, Idaho, in areas with varying amounts and types of vegetation cover. A software program called SamplePoint was used along with visual inspection to evaluate percent cover for the six cover types. Results were compared against standard field measurements to assess accuracy. The comparison of fixed-wing and helicopter UAV technology against field estimates shows good agreement for the measurement of bare ground. This study shows that if a high degree of detail and data accuracy is desired, then a helicopter UAV may be a good platform to use. If the data collection objective is to assess broad-scale landscape level changes, then the collection of imagery with a fixed-wing system is probably more appropriate.

  17. Impact assessment of an intervention on the consumption of fruits and vegetables by students and teachers

    OpenAIRE

    Silvia Cristina Farias; Inês Rugani Ribeiro de Castro; Virgínia Martins da Matta; Luciana Maria Cerqueira Castro

    2014-01-01

    OBJECTIVE: To evaluate the impact of an intervention that promoted the consumption of fruits and vegetables on the intake of these products by students and teachers in Rio de Janeiro (RJ), Brazil. METHODS: This is a one-group pretest-posttest study of students and teachers from elementary public schools in Rio de Janeiro. The intervention included a training course for promoting healthy eating; distribution of educational materials; and holding of a one-day health fair. We assessed the act...

  18. Health Risk Assessment of Pesticide Residues via Dietary Intake of Market Vegetables from Dhaka, Bangladesh

    OpenAIRE

    Md. Shakhaoat Hossain; Md. Alamgir Hossain; Md. Abdur Rahman; Md Mainul Islam; Md Atiqur Rahman; Tanveer Mehedi Adyel

    2013-01-01

    The present study was designed to assess the health risk of pesticide residues via dietary intake of vegetables collected from four top agro-based markets of Dhaka, Bangladesh. High performance liquid chromatography with a photo diode array detector (HPLC-PDA) was used to determine six organophosphorus (chlorpyrifos, fenitrothion, parathion, ethion, acephate, fenthion), two carbamate (carbaryl and carbofuran) and one pyrethroid (cypermethrin) pesticide residues in twelve samples of three comm...

  19. Honey Production for Assessing the Impact of Climatic Changes on Vegetation

    OpenAIRE

    Schweitzer, P.; Nombré, I.; Boussim, JI.

    2013-01-01

    Burkina Faso is experiencing the effects of climate change in all sectors of its agriculture, including honey production. This study assessed the impact of climatic factors on countries' vegetation through honey production. Honey production of nine apiaries consisting of 165 rectangular movable frames beehives was monitored over a seven year period starting from 2002 to 2008. Climatic data such as rainfall, temperature and wind speed were obtained from the nearest meteorological station. Line...

  20. Toxicity reduction in an industrial nitro-aromatic wastewater plant: an assessment and a proposed improvement.

    Science.gov (United States)

    Lu, Zhao-Yang; Jiang, Bi-Cun; Li, Ai-Min; Guo, Hong-Yan; Sun, Shu-Guang; Chu, Li-Mei

    2012-01-01

    In this study, the performance of a typical Chinese industrial nitro-aromatic wastewater project (operational capacity: 3,000 m(3)d(-1)) was evaluated using chemical properties and toxicity data. Additionally, the relationship between the removal of organic pollutants and toxicity reduction was investigated throughout the whole-process wastewater treatment. Current advanced treatment reduced the dissolved organic carbon by 40% compared with biologically treated wastewater effluent (BTWE), but the acute toxicity and early life-stage toxicity increased significantly. For instance, the acute toxicity of the current advanced treated wastewater was 450% greater than that of the untreated BTWE. With the aim of effectively decreasing the toxicity of the effluent, several efficient adsorption technologies were assessed and compared for further treatment of BTWE. Coagulation and/or oxidation coupled with activated carbon adsorption, hypercrosslinked resin adsorption, or MIEX(®) technology was helpful for improving chemical indices and reducing toxicity. Among these adsorption treatment technologies, hypercrosslinked resin adsorption was more effective at removing most of the toxicants than MIEX(®) technology, and it also had better regeneration efficiency and mechanical properties compared with activated carbon. Therefore, hypercrosslinked resin adsorption may be a promising technology for enhancing organic pollutant removal and toxicity reduction of BTWE from nitro-aromatic factories. PMID:22699348

  1. Toxicity assessment of Erythrophleum ivorense and Parquetina nigrescens

    Directory of Open Access Journals (Sweden)

    Louis Adu-Amoah

    2014-01-01

    Full Text Available Erythrophleum ivorense and Parquetina nigrescens are found growing in tropical regions and they are used in African traditional medicine to treat various ailments including wounds, boils and anaemic conditions. Some species of plant in the Erythrophleum genus are also known to be poisonous and toxic to several livestock. However, there is no information on the toxicity of E. ivorense and P. nigrescens. This study is to determine the cytotoxicity and subchronic toxicity properties of methanol leaf extract (EIML and methanol stem barks extract (EIMB of E. ivorense and methanol leaf and aerial part extract of P. nigrescens (PNML. Concentrations from 0.1 to 100 μg/mL of the extracts were used to determine the influence of the extracts on the release of lactate dehydrogenase (LDH from HaCaT keratinocytes. The EIML and EIMB extracts showed increase in LDH released from HaCaT keratinocytes at 0.1–10 μg/mL and 1–100 μg/mL for the PNML extracts (p > 0.05. Wistar rats were orally administered with 100, 300 and 1000 mg/kg body weight of the extracts (EIML, EIMB and PNML, respectively for 35 days. Tissues from the kidney and liver of the rats treated with lower doses (100–300 mg/kg body weight of EIML extract showed highly vascularized kidneys with numerous glomerular tufts, healthy hepatocytes and sinusoids in liver. However, there were persistent renal tissue inflammation and glomerular degeneration in kidney, and increased inflammatory infiltrates with few vacuolations and scarrings in liver in rats treated with higher extract dose of 1000 mg/kg body weight of rat. The rats treated with EIMB extract showed persistent renal and hepatocyte inflammations with glomerular and hepatocyte necrosis at all administered doses (100, 300 and 1000 mg/kg body weight which are indications of renal and hepatic toxicities. Though rats administered with 100 and 300 mg/kg of PNML extract showed renal haemorrhage and inflammation and hepatic inflammation, the rats

  2. Assessing Measures of Order Flow Toxicity via Perfect Trade Classification

    DEFF Research Database (Denmark)

    Andersen, Torben G.; Bondarenko, Oleg

    The VPIN, or Volume-synchronized Probability of INformed trading, metric is introduced by Easley, Lopez de Prado and O'Hara (ELO) as a real-time indicator of order flow toxicity. They find the measure useful in predicting return volatility and conclude it may help signal impending market turmoil....... The VPIN metric involves decomposing volume into active buys and sells. We use the best-bid-offer (BBO) files from the CME Group to construct (near) perfect trade classification measures for the E-mini S&P 500 futures contract. We investigate the accuracy of the ELO Bulk Volume Classification (BVC) scheme...

  3. Probabilistic ecological risk assessment of effluent toxicity of a wastewater reclamation plant based on process modeling.

    Science.gov (United States)

    Zeng, Siyu; Huang, Yunqing; Sun, Fu; Li, Dan; He, Miao

    2016-09-01

    The growing use of reclaimed wastewater for environmental purposes such as stream flow augmentation requires comprehensive ecological risk assessment and management. This study applied a system analysis approach, regarding a wastewater reclamation plant (WRP) and its recipient water body as a whole system, and assessed the ecological risk of the recipient water body caused by the WRP effluent. Instead of specific contaminants, two toxicity indicators, i.e. genotoxicity and estrogenicity, were selected to directly measure the biological effects of all bio-available contaminants in the reclaimed wastewater, as well as characterize the ecological risk of the recipient water. A series of physically based models were developed to simulate the toxicity indicators in a WRP through a typical reclamation process, including ultrafiltration, ozonation, and chlorination. After being validated against the field monitoring data from a full-scale WRP in Beijing, the models were applied to simulate the probability distribution of effluent toxicity of the WRP through Latin Hypercube Sampling to account for the variability of influent toxicity and operation conditions. The simulated effluent toxicity was then used to derive the predicted environmental concentration (PEC) in the recipient stream, considering the variations of the toxicity and flow of the upstream inflow as well. The ratio of the PEC of each toxicity indicator to its corresponding predicted no-effect concentration was finally used for the probabilistic ecological risk assessment. Regional sensitivity analysis was also performed with the developed models to identify the critical control variables and strategies for ecological risk management.

  4. Probabilistic ecological risk assessment of effluent toxicity of a wastewater reclamation plant based on process modeling.

    Science.gov (United States)

    Zeng, Siyu; Huang, Yunqing; Sun, Fu; Li, Dan; He, Miao

    2016-09-01

    The growing use of reclaimed wastewater for environmental purposes such as stream flow augmentation requires comprehensive ecological risk assessment and management. This study applied a system analysis approach, regarding a wastewater reclamation plant (WRP) and its recipient water body as a whole system, and assessed the ecological risk of the recipient water body caused by the WRP effluent. Instead of specific contaminants, two toxicity indicators, i.e. genotoxicity and estrogenicity, were selected to directly measure the biological effects of all bio-available contaminants in the reclaimed wastewater, as well as characterize the ecological risk of the recipient water. A series of physically based models were developed to simulate the toxicity indicators in a WRP through a typical reclamation process, including ultrafiltration, ozonation, and chlorination. After being validated against the field monitoring data from a full-scale WRP in Beijing, the models were applied to simulate the probability distribution of effluent toxicity of the WRP through Latin Hypercube Sampling to account for the variability of influent toxicity and operation conditions. The simulated effluent toxicity was then used to derive the predicted environmental concentration (PEC) in the recipient stream, considering the variations of the toxicity and flow of the upstream inflow as well. The ratio of the PEC of each toxicity indicator to its corresponding predicted no-effect concentration was finally used for the probabilistic ecological risk assessment. Regional sensitivity analysis was also performed with the developed models to identify the critical control variables and strategies for ecological risk management. PMID:27219046

  5. Constructing Virtual Forest Scenes for Assessment of Sub-pixel Vegetation Structure From Imaging Spectroscopy

    Science.gov (United States)

    Gerace, A. D.; Yao, W.; van Aardt, J. A.; Romanczyk, P.; Kelbe, D.; van Leeuwen, M.; Kampe, T. U.

    2015-12-01

    Assessment of vegetation structure via remote sensing modalities has a long history for a range of sensor platforms. Imaging spectroscopy, while often used for biochemical measurements, also applies to structural assessment in that the Hyperspectral Infrared Imager (HyspIRI), for instance, will provide an opportunity to monitor the global ecosystem. Establishing the linkage between HyspIRI data and sub-pixel vegetation structural variation therefore is of keen interest to the remote sensing and ecology communities. NASA's AVIRIS-C was used to collect airborne data during the 2013-2015 time frame, while ground truth data were limited to 2013 due to time-consuming and labor-intensive nature of field data collection. We augmented the available field data with a first-principles, physics-based simulation approach to refine our field efforts and to maintain larger control over within-pixel variation and associated assessments. Three virtual scenes were constructed for the study, corresponding to the actual vegetation structure of the NEON's Pacific Southwest site (Fresno, CA). They presented three typical forest types: oak savanna, dense coniferous forest, and conifer manzanita mixed forest. Airborne spectrometer and a field leaf area index sensor were simulated over these scenes using the Digital Imaging and Remote Sensing Image Generation (DIRSIG) Model, a synthetic image generation model. After verifying the geometrical parameters and physical model with those replicative senses, more scenes could be constructed by changing one or more vegetation structural parameters, such as forest density, tree species, size, location, and within-pixel distribution. We constructed regression models of leaf area index (LAI, R2=0.92) and forest density(R2=0.97) with narrow-band vegetation indices through simulation. Those models can be used to improve the HyspIRI's suitability for consistent global vegetation structural assessments. The virtual scene and model can also be used in

  6. Occupational health assessment of chromite toxicity among Indian miners

    Directory of Open Access Journals (Sweden)

    Alok Prasad Das

    2011-01-01

    Full Text Available Elevated concentration of hexavalent chromium pollution and contamination has contributed a major health hazard affecting more than 2 lakh mine workers and inhabitants residing in the Sukinda chromite mine of Odisha, India. Despite people suffering from several forms of ill health, physical and mental deformities, constant exposure to toxic wastes and chronic diseases as a result of chromite mining, there is a tragic gap in the availability of ′scientific′ studies and data on the health hazards of mining in India. Occupational Safety and Health Administration, Odisha State Pollution Control Board and the Odisha Voluntary Health Association data were used to compile the possible occupational health hazards, hexavalent chromium exposure and diseases among Sukinda chromite mines workers. Studies were reviewed to determine the routes of exposure and possible mechanism of chromium induced carcinogenicity among the workers. Our studies suggest all forms of hexavalent chromium are regarded as carcinogenic to workers however the most important routes of occupational exposure to Cr (VI are inhalation and dermal contact. This review article outlines the physical, chemical, biological and psychosocial occupational health hazards of chromite mining and associated metallurgical processes to monitor the mining environment as well as the miners exposed to these toxicants to foster a safe work environment. The authors anticipate that the outcome of this manuscript will have an impact on Indian chromite mining industry that will subsequently bring about improvements in work conditions, develop intervention experiments in occupational health and safety programs.

  7. The use of a vegetation index for assessment of the urban heat island effect

    Science.gov (United States)

    Gallo, K. P.; Mcnab, A. L.; Karl, T. R.; Brown, J. F.; Hood, J. J.; Tarpley, J. D.

    1993-01-01

    A vegetation index and radiative surface temperature were derived from NOAA-11 Advanced Very High Resolution Radiometer (AVHRR) data for the Seattle, WA region from 28 June through 4 July 1991. The vegetation index and surface temperature values were computed for locations of weather observation stations within the region and compared to observed minimum air temperatures. These comparisons were used to evaluate the use of AVHRR data to assess the influence of the urban environment on observed minimum air temperatures (the urban heat island effect). AVHRR derived normalized difference vegetation index (NDVI) and radiant surface temperature data from a one week composite product were both related significantly to observed minimum temperatures, however, the vegetation index accounted for a greater amount of the spatial variation observed in mean minimum temperatures. The difference in the NDVI between urban and rural regions appears to be an indicator of the difference in surface properties (i.e., evaporation and heat storage capacity) between the two environments that are responsible for differences in urban and rural minimum temperatures.

  8. Rapid assessment of toxicity of oil sands process-affected waters using fish cell lines

    International Nuclear Information System (INIS)

    Oil-sand process-affected waters (OSPAW) are being evaluated in acute and chronic toxicity tests with various model organisms to assess the safety of reclamation ponds where OSPAWs are being deposited. Classical toxicity assays typically require large volumes of test waters, take time and are costly. They may also require expensive analytical assays to characterize the contaminants present. Cytotoxicity assays using indigenous and model fish cell lines may prove useful for a prompt comparative toxicity assessment of copious samples retrieved at various temporal and spatial sites at a fraction of cost and time compared to in vivo assays. This presentation reported on a study in which a rapid fluorometric assay using several fish cell lines was used to assess the acute toxicity of 20 water samples including OSPAW. The water samples were mixed with media salts and evaluated directly on cells in culture without prior extraction procedures. The evaluation was done in blind and a consistent pattern of toxicity was observed with the tested cell lines. It was concluded that this approach may minimize the need of using whole organisms for toxicity assessment of OSPAW.

  9. TOXICITY ASSESSMENT OF PHOSPHONIUM BASED IONIC LIQUIDS TOWARDS FEMALE GUPPY FISH

    Directory of Open Access Journals (Sweden)

    Mohanad El-Harbawi

    2013-01-01

    Full Text Available In this study, two phosphonium based ionic liquids (butyl triphenyl phosphonium chloride and hexyl triphenyl phosphonium bromide have been synthesized using quarternisation process. The toxicities of these Ionic Liquids (ILs are unknown and may be harmful to humans and the environment. Therefore, the toxicity assessment of these ILs was carried out according to the Organization for Economic Cooperation and Development (OECD 203 guideline using female guppy fish (Poecilia reticulata. The median Lethal Concentrations (LC50 have been estimated for butyl triphenyl phosphonium chloride and for hexyl triphenyl phosphonium bromide to be 73.35 and 61.36 mg L-1 respectively. Both LC50 obtained can be identified as slightly toxic ILs based on Acute Toxicity Rating Scale by Fish and Wildlife Service (FWS. The findings from this study can be used for better design of phosphonium-based ILs with consideration of their aquatic toxicities.

  10. Assessing the pulmonary toxicity of single-walled carbon nanohorns

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, Rachel M [ORNL; Voy, Brynn H [ORNL; Glass-Mattie, Dana F [ORNL; Mahurin, Shannon Mark [ORNL; Saxton, Arnold [University of Tennessee, Knoxville (UTK); Donnel, Robert L. [University of Tennessee, Knoxville (UTK); Cheng, Mengdawn [ORNL

    2007-01-01

    Previous studies have suggested that single-walled carbon nanotubes (SWCNTs) may be pose a pulmonary hazard. We investigated the pulmonary toxicity of single-walled carbon nanohorns (SWCNHs), a relatively new carbon-based nanomaterial that is structurally similar to SWCNTs. Mice were exposed to 30 g of surfactant-suspended SWCNHs by pharyngeal aspiration and sacrificed 24 hours or 7 days post exposure. Total and differential cell counts and cytokine analysis of bronchoalveolar lavage fluid demonstrated a mild inflammatory response which was mitigated by day 7 post exposure. Whole lung microarray analysis demonstrated that SWCNH-exposure did not lead to robust changes in gene expression. Finally, histological analysis showed no evidence of granuloma formation or fibrosis following SWCNH aspiration. These combined results suggest that SWCNH is a relatively innocuous nanomaterial when delivered to mice in vivo using aspiration as a delivery mechanism.

  11. Assessing the pulmonary toxicity of single-walled carbon nanohorns

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, Rachel M [ORNL; Voy, Brynn H [ORNL; Glass-Mattie, Dana F [ORNL; Mahurin, Shannon Mark [ORNL; Saxton, Arnold [University of Tennessee, Knoxville (UTK); Donnel, Robert L. [University of Tennessee, Knoxville (UTK); Cheng, Mengdawn [ORNL

    2007-01-01

    Previous studies have suggested that single-walled carbon nanotubes (SWCNTs) may pose a pulmonary hazard. We investigated the pulmonary toxicity of single-walled carbon nanohorns (SWCNHs), a relatively new carbon-based nanomaterial that is structurally similar to SWCNTs. Mice were exposed to 30 {micro}g of surfactant-suspended SWCNHs or an equal volume of vehicle control by pharyngeal aspiration and sacrificed 24 hours or 7 days post-exposure. Total and differential cell counts and cytokine analysis of bronchoalveolar lavage fluid demonstrated a mild inflammatory response which was mitigated by day 7 post-exposure. Whole lung microarray analysis demonstrated that SWCNH-exposure did not lead to robust changes in gene expression. Finally, histological analysis showed no evidence of granuloma formation or fibrosis following SWCNH aspiration. These combined results suggest that SWCNH is a relatively innocuous nanomaterial when delivered to mice in vivo using aspiration as a delivery mechanism.

  12. TOXIC SUBSTANCES FROM COAL COMBUSTION: A COMPREHENSIVE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    C.L. Senior; T. Panagiotou; J.O.L. Wendt; W. Seames; F.E. Huggins; G.P Huffman; N. Yap; M.R. Ames; I.Olmez; T. Zeng; A.F. Sarofim; A. Kolker; R. Finkelman; J.J. Helble

    1998-07-16

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the Federal Energy Technology Center (FETC), the Electric Power Research Institute, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, the Massachusetts Institute of Technology (MIT), the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (W) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NO{sub x} combustion systems, and new power generation plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). This report covers the reporting period from the submission of the draft Phase 1 Final Report through the end of June, 1998. During this period two of the three Phase 2 coals were procured and pulverized samples were distributed to team members. Analysis of Phase 1 X-Ray Absorption Fine Structure (XAFS) data, particularly of mercury in sorbent samples, continued. An improved method for identifying mercury compounds on sorbents was developed, leading to a clearer understanding of forms of mercury in char and sorbents exposed to flue gas. Additional analysis of Phase 1 large scale combustion data was performed to investigate mechanistic information related to the fate of the radionuclides Cs, Th, and Co. Modeling work for this period was focused on building and testing a sub-model for

  13. Assessment of toxic metals in waste personal computers

    Energy Technology Data Exchange (ETDEWEB)

    Kolias, Konstantinos; Hahladakis, John N., E-mail: john_chach@yahoo.gr; Gidarakos, Evangelos, E-mail: gidarako@mred.tuc.gr

    2014-08-15

    Highlights: • Waste personal computers were collected and dismantled in their main parts. • Motherboards, monitors and plastic housing were examined in their metal content. • Concentrations measured were compared to the RoHS Directive, 2002/95/EC. • Pb in motherboards and funnel glass of devices released <2006 was above the limit. • Waste personal computers need to be recycled and environmentally sound managed. - Abstract: Considering the enormous production of waste personal computers nowadays, it is obvious that the study of their composition is necessary in order to regulate their management and prevent any environmental contamination caused by their inappropriate disposal. This study aimed at determining the toxic metals content of motherboards (printed circuit boards), monitor glass and monitor plastic housing of two Cathode Ray Tube (CRT) monitors, three Liquid Crystal Display (LCD) monitors, one LCD touch screen monitor and six motherboards, all of which were discarded. In addition, concentrations of chromium (Cr), cadmium (Cd), lead (Pb) and mercury (Hg) were compared with the respective limits set by the RoHS 2002/95/EC Directive, that was recently renewed by the 2012/19/EU recast, in order to verify manufacturers’ compliance with the regulation. The research included disassembly, pulverization, digestion and chemical analyses of all the aforementioned devices. The toxic metals content of all samples was determined using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The results demonstrated that concentrations of Pb in motherboards and funnel glass of devices with release dates before 2006, that is when the RoHS Directive came into force, exceeded the permissible limit. In general, except from Pb, higher metal concentrations were detected in motherboards in comparison with plastic housing and glass samples. Finally, the results of this work were encouraging, since concentrations of metals referred in the RoHS Directive were found in

  14. Assessment of Supercritical Fluid Extraction Use in Whole Sediment Toxicity Identification Evaluations

    Science.gov (United States)

    In this investigation, supercritical fluid extraction (SFE) with pure CO2 was assessed as a confirmatory tool in Phase III of whole sediment toxicity identification evaluations (TIEs). The SFE procedure was assessed on two reference sediments and three contaminated sediments usi...

  15. Assessment of Jatropha curcas L. biodiesel seed cake toxicity using the zebrafish (Danio rerio) embryo toxicity (ZFET) test.

    Science.gov (United States)

    Hallare, Arnold V; Ruiz, Paulo Lorenzo S; Cariño, J C Earl D

    2014-05-01

    Consequent to the growing demand for alternative sources of energy, the seeds from Jatropha curcas remain to be the favorite for biodiesel production. However, a significant volume of the residual organic mass (seed cake) is produced during the extraction process, which raises concerns on safe waste disposal. In the present study, we assessed the toxicity of J. curcas seed cake using the zebrafish (Danio rerio) embryotoxicity test. Within 1-h post-fertilization (hpf), the fertilized eggs were exposed to five mass concentrations of J. curcas seed cake and were followed through 24, 48, and 72 hpf. Toxicity was evaluated based on lethal endpoints induced on zebrafish embryos namely egg coagulation, non-formation of somites, and non-detachment of tail. The lowest concentration tested, 1 g/L, was not able to elicit toxicity on embryos whereas 100 % mortality (based also on lethal endpoints) was recorded at the highest concentration at 2.15 g/L. The computed LC50 for the J. curcas seed cake was 1.61 g/L. No further increase in mortality was observed in the succeeding time points (48 and 72 hpf) indicating that J. curcas seed cake exerted acute toxicity on zebrafish embryos. Sublethal endpoints (yolk sac and pericardial edema) were noted at 72 hpf in zebrafish embryos exposed to higher concentrations. The observed lethal endpoints induced on zebrafish embryos were discussed in relation to the active principles, notably, phorbol esters that have remained in the seed cake even after extraction.

  16. Development of a Fully Automated Flow Injection Analyzer Implementing Bioluminescent Biosensors for Water Toxicity Assessment

    Directory of Open Access Journals (Sweden)

    Constantinos Georgiou

    2010-07-01

    Full Text Available This paper describes the development of an automated Flow Injection analyzer for water toxicity assessment. The analyzer is validated by assessing the toxicity of heavy metal (Pb2+, Hg2+ and Cu2+ solutions. One hundred μL of a Vibrio fischeri suspension are injected in a carrier solution containing different heavy metal concentrations. Biosensor cells are mixed with the toxic carrier solution in the mixing coil on the way to the detector. Response registered is % inhibition of biosensor bioluminescence due to heavy metal toxicity in comparison to that resulting by injecting the Vibrio fischeri suspension in deionised water. Carrier solutions of mercury showed higher toxicity than the other heavy metals, whereas all metals show concentration related levels of toxicity. The biosensor’s response to carrier solutions of different pHs was tested. Vibrio fischeri’s bioluminescence is promoted in the pH 5–10 range. Experiments indicate that the whole cell biosensor, as applied in the automated fluidic system, responds to various toxic solutions.

  17. Development of a fully automated Flow Injection analyzer implementing bioluminescent biosensors for water toxicity assessment.

    Science.gov (United States)

    Komaitis, Efstratios; Vasiliou, Efstathios; Kremmydas, Gerasimos; Georgakopoulos, Dimitrios G; Georgiou, Constantinos

    2010-01-01

    This paper describes the development of an automated Flow Injection analyzer for water toxicity assessment. The analyzer is validated by assessing the toxicity of heavy metal (Pb(2+), Hg(2+) and Cu(2+)) solutions. One hundred μL of a Vibrio fischeri suspension are injected in a carrier solution containing different heavy metal concentrations. Biosensor cells are mixed with the toxic carrier solution in the mixing coil on the way to the detector. Response registered is % inhibition of biosensor bioluminescence due to heavy metal toxicity in comparison to that resulting by injecting the Vibrio fischeri suspension in deionised water. Carrier solutions of mercury showed higher toxicity than the other heavy metals, whereas all metals show concentration related levels of toxicity. The biosensor's response to carrier solutions of different pHs was tested. Vibrio fischeri's bioluminescence is promoted in the pH 5-10 range. Experiments indicate that the whole cell biosensor, as applied in the automated fluidic system, responds to various toxic solutions. PMID:22163592

  18. Application of simple and low-cost toxicity tests for ecotoxicological assessment of industrial wastewaters.

    Science.gov (United States)

    Aydin, Mehmet Emin; Aydin, Senar; Tongur, Süheyla; Kara, Gülnihal; Kolb, Marit; Bahadir, Müfit

    2015-01-01

    The objective of this study was to identify and to apply appropriate biotests having the advantages of being highly sensitive, easy to run, relatively inexpensive and able to substitute fish toxicity tests due to ethical reasons of animal welfare. To perform an ecotoxicological assessment of industrial wastewaters, different microbiotests were conducted to substitute the fish toxicity test with Lebistes reticulatus through Vibrio fischeri, Thamnocephalus platyurus, Daphnia magna, Lemna minor and Lepidium sativum representing different trophic levels in the aquatic and terrestrial ecosystems. Also, Algaltox F(TM) with Pseudokirchneriella subcapitata and Protox F(TM) with Tetrahymena thermophila tests were carried out. However, they could not be applied successfully for the wastewater samples. Wastewater samples from seven different industrial zones comprising different industries were subjected to characterization through measuring their physical-chemical parameters and their toxicity versus the above-mentioned organisms. T. platyurus, D. magna and L. reticulatus were the most sensitive test organisms investigated for the wastewaters. Considering toxic unit values, generally wastewater samples were toxic according to Thamnotox F(TM), Daphtox F(TM) and fish toxicity tests. As an important outcome, it was concluded that Daphtox F(TM) and Thamnotox F(TM) could be a good alternative for the fish toxicity test, which is so far the sole toxicity test accepted by the Turkish Water Pollution Control Regulation. PMID:25951939

  19. Use of passive samplers for improving oil toxicity and spill effects assessment

    International Nuclear Information System (INIS)

    Highlights: • Methods to quantify dissolved hydrocarbons needed to link oil exposures to toxicity. • Solid phase microextraction (SPME) fibers used to measure dissolved hydrocarbons. • SPME results reliably predicted acute toxicity for range of dispersed oils. • Oil droplets and chemical dispersant did not significantly contribute to toxicity. • SPME analysis improves oil exposure assessment in lab and field studies. - Abstract: Methods that quantify dissolved hydrocarbons are needed to link oil exposures to toxicity. Solid phase microextraction (SPME) fibers can serve this purpose. If fibers are equilibrated with oiled water, dissolved hydrocarbons partition to and are concentrated on the fiber. The absorbed concentration (Cpolymer) can be quantified by thermal desorption using GC/FID. Further, given that the site of toxic action is hypothesized as biota lipid and partitioning of hydrocarbons to lipid and fibers is well correlated, Cpolymer is hypothesized to be a surrogate for toxicity prediction. To test this method, toxicity data for physically and chemically dispersed oils were generated for shrimp, Americamysis bahia, and compared to test exposures characterized by Cpolymer. Results indicated that Cpolymer reliably predicted toxicity across oils and dispersions. To illustrate field application, SPME results are reported for oil spills at the Ohmsett facility. SPME fibers provide a practical tool to improve characterization of oil exposures and predict effects in future lab and field studies

  20. Microtox Toxicity Assay for the Sediment Quality Assessment of Ganga River

    OpenAIRE

    K. R. Beg; Ali, S.

    2008-01-01

    The objective of this study was to determine the sediment quality assessment of Ganga River at Kanpur city where effluents from tannery industries are discharged. Sediment samples from control, upstream and downstream area were collected and analyzed for bacterial toxicity bioassay along with a reference sediment (LGC6137). The control samples collected from the point of origin of Ganga River at Deoparyag were found non toxic to the bacteria and served as negative controls for the test method...

  1. Toxicity Assessment of the Xanthid Crab Demania cultripes from Cebu Island, Philippines

    OpenAIRE

    Manabu Asakawa; Gloria Gomez-Delan; Shintaro Tsuruda; Michitaka Shimomura; Yasuo Shida; Shigeto Taniyama; Mercy Barte-Quilantang; Jo Shindo

    2010-01-01

    Several cases of poisoning resulting in human fatalities and stemming from the ingestion of coral reef crabs have been reported from the Indo-Pacific region. We assessed the toxicity of the unidentified xanthid crab collected from the Camotes Sea off the eastern coast of Cebu Island, central Visayas region of Philippines from the food hygienic point of view. All seven specimens, which were identified with Demania cultripes, collected in 2006 were toxic to mice irrespective of the season of co...

  2. A meta-analysis of medicinal plants to assess the evidence for toxicity

    OpenAIRE

    Chen, Sarah; Vieira, Amandio

    2010-01-01

    Toxicity of phytochemicals, plant-based extracts and dietary supplements, and medicinal plants in general, is of medical importance and must be considered in phytotherapy and other plant uses. We show in this report how general database analyses can provide a quantitative assessment of research and evidence related to toxicity of medicinal plants or specific phytochemicals. As examples, several medicinal plants are analyzed for their relation to nephrotoxicity and hepatotoxicity. The results ...

  3. Nutrition Can Modulate the Toxicity of Environmental Pollutants: Implications in Risk Assessment and Human Health

    OpenAIRE

    Hennig, Bernhard; Ormsbee, Lindell; Craig J. McClain; Watkins, Bruce A.; Blumberg, Bruce; Bachas, Leonidas G.; Sanderson, Wayne; Thompson, Claudia; Suk, William A.

    2012-01-01

    Background: The paradigm of human risk assessment includes many variables that must be viewed collectively in order to improve human health and prevent chronic disease. The pathology of chronic diseases is complex, however, and may be influenced by exposure to environmental pollu-tants, a sedentary lifestyle, and poor dietary habits. Much of the emerging evidence suggests that nutrition can modulate the toxicity of environmental pollutants, which may alter human risks associated with toxicant...

  4. Assessment of Atmospheric Algorithms to Retrieve Vegetation in Natural Protected Areas Using Multispectral High Resolution Imagery

    Directory of Open Access Journals (Sweden)

    Javier Marcello

    2016-09-01

    Full Text Available The precise mapping of vegetation covers in semi-arid areas is a complex task as this type of environment consists of sparse vegetation mainly composed of small shrubs. The launch of high resolution satellites, with additional spectral bands and the ability to alter the viewing angle, offers a useful technology to focus on this objective. In this context, atmospheric correction is a fundamental step in the pre-processing of such remote sensing imagery and, consequently, different algorithms have been developed for this purpose over the years. They are commonly categorized as imaged-based methods as well as in more advanced physical models based on the radiative transfer theory. Despite the relevance of this topic, a few comparative studies covering several methods have been carried out using high resolution data or which are specifically applied to vegetation covers. In this work, the performance of five representative atmospheric correction algorithms (DOS, QUAC, FLAASH, ATCOR and 6S has been assessed, using high resolution Worldview-2 imagery and field spectroradiometer data collected simultaneously, with the goal of identifying the most appropriate techniques. The study also included a detailed analysis of the parameterization influence on the final results of the correction, the aerosol model and its optical thickness being important parameters to be properly adjusted. The effects of corrections were studied in vegetation and soil sites belonging to different protected semi-arid ecosystems (high mountain and coastal areas. In summary, the superior performance of model-based algorithms, 6S in particular, has been demonstrated, achieving reflectance estimations very close to the in-situ measurements (RMSE of between 2% and 3%. Finally, an example of the importance of the atmospheric correction in the vegetation estimation in these natural areas is presented, allowing the robust mapping of species and the analysis of multitemporal variations

  5. Multifaceted toxicity assessment of catalyst composites in transgenic zebrafish embryos.

    Science.gov (United States)

    Jang, Gun Hyuk; Lee, Keon Yong; Choi, Jaewon; Kim, Sang Hoon; Lee, Kwan Hyi

    2016-09-01

    Recent development in the field of nanomaterials has given rise into the inquiries regarding the toxicological characteristics of the nanomaterials. While many individual nanomaterials have been screened for their toxicological effects, composites that accompany nanomaterials are not common subjects to such screening through toxicological assessment. One of the widely used composites that accompany nanomaterials is catalyst composite used to reduce air pollution, which was selected as a target composite with nanomaterials for the multifaceted toxicological assessment. As existing studies did not possess any significant data regarding such catalyst composites, this study focuses on investigating toxicological characteristics of catalyst composites from various angles in both in-vitro and in-vivo settings. Initial toxicological assessment on catalyst composites was conducted using HUVECs for cell viability assays, and subsequent in-vivo assay regarding their direct influence on living organisms was done. The zebrafish embryo and its transgenic lines were used in the in-vivo assays to obtain multifaceted analytic results. Data obtained from the in-vivo assays include blood vessel formation, mutated heart morphology, and heart functionality change. Our multifaceted toxicological assessment pointed out that chemical composites augmented with nanomaterials can too have toxicological threat as much as individual nanomaterials do and alarms us with their danger. This manuscript provides a multifaceted assessment for composites augmented with nanomaterials, of which their toxicological threats have been overlooked.

  6. Multifaceted toxicity assessment of catalyst composites in transgenic zebrafish embryos.

    Science.gov (United States)

    Jang, Gun Hyuk; Lee, Keon Yong; Choi, Jaewon; Kim, Sang Hoon; Lee, Kwan Hyi

    2016-09-01

    Recent development in the field of nanomaterials has given rise into the inquiries regarding the toxicological characteristics of the nanomaterials. While many individual nanomaterials have been screened for their toxicological effects, composites that accompany nanomaterials are not common subjects to such screening through toxicological assessment. One of the widely used composites that accompany nanomaterials is catalyst composite used to reduce air pollution, which was selected as a target composite with nanomaterials for the multifaceted toxicological assessment. As existing studies did not possess any significant data regarding such catalyst composites, this study focuses on investigating toxicological characteristics of catalyst composites from various angles in both in-vitro and in-vivo settings. Initial toxicological assessment on catalyst composites was conducted using HUVECs for cell viability assays, and subsequent in-vivo assay regarding their direct influence on living organisms was done. The zebrafish embryo and its transgenic lines were used in the in-vivo assays to obtain multifaceted analytic results. Data obtained from the in-vivo assays include blood vessel formation, mutated heart morphology, and heart functionality change. Our multifaceted toxicological assessment pointed out that chemical composites augmented with nanomaterials can too have toxicological threat as much as individual nanomaterials do and alarms us with their danger. This manuscript provides a multifaceted assessment for composites augmented with nanomaterials, of which their toxicological threats have been overlooked. PMID:27364464

  7. Accuracy assessment of airphoto interpretation of vegetation types and disturance levels on winter seismic trails, Arctic National Wildlife Refuge, Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — An accuracy assessment was conducted to evaluate the photointerpretation of vegetation types and disturbance levels along seismic trails in the Arctic National...

  8. Accuracy assessment of airphoto interpretation of vegetation types and disturance levels on winter seismic trails, Arctic National Wildlife Refuge, Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — An accuracy assessment was conducted to evaluate the photo-interpretation of vegetation types and disturbance levels along seismic trails in the Arctic National...

  9. Pu`ukohola Heiau National Historic Site Vegetation Mapping Project - Field Plots, Observation and Accuracy Assessment Points

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the 2008 vegetation (classification) field plots (spatial database) and 2010 accuracy assessment points (spatial database) created from the...

  10. 解毒机对蔬菜中剧毒有机磷农药降解效果的评价%Evaluation on degradation effect for highly toxic organophosphorus pesticide in vegetable by a detoxification machine

    Institute of Scientific and Technical Information of China (English)

    周金森; 刘赐敏; 龙军标; 刘钰钗

    2013-01-01

    [Objective] To understand the degradation effect of highly toxic organophosphorus pesticide in vegetable treated by a detoxification machine.[Methods] The vegetables,including lettuce,Brassicachinensis L,green bean and cucumber polluted by methamidophos,monocrotophos,dimethoate,parathion were treated by a detoxification machine,while the tap water soak was taken as comparison.In the end,their degradation effects were assessed by a capillary gas chromatography.[Results] The optimal detoxification time for machine was 20 min.The degradation rates of methamidophos in 4 kinds of vegetables were 72.13%-79.86%,monocrotophos were 74.58%-81.99%,dimethoate were 49.33%-55.08%,parathion were 57.34%-60.03%The optimal detoxification time for tap water was 30 min,the degradation rates of 4 kinds of organophosphorus pesticide in vegetables were 19.74%-35.91%.[Conclusion] The detoxification machine is quick to degrade highly toxic organophosphorus pesticide in vegetables with good effect.%目的 了解解毒机对蔬菜中多种剧毒有机磷农药降解情况.方法 将残留在生菜、上海青、四季豆、黄瓜上的甲胺磷、久效磷、乐果和对硫磷,用解毒机进行清洗,同时用自来水浸泡作对照,然后采用毛细管柱气相色谱法测定,计算降解率,评价其降解效果.结果 解毒机清洗蔬菜20 min达最佳,在4种蔬菜中甲胺磷的降解率为72.13% ~79.86%,久效磷为74.58%~ 81.99%,乐果为49.33% ~ 55.08%,对硫磷为57.34% ~60.03%.自来水浸泡蔬菜30 min达最佳,在4种蔬菜中4种农药的降解率在19.74% ~35.91%之间.结论 解毒机对蔬菜中剧毒有机磷农药降解速度快,效果好.

  11. The assessment of sewage sludge gasification by-products toxicity by ecotoxicologial test.

    Science.gov (United States)

    Werle, Sebastian; Dudziak, Mariusz

    2015-08-01

    The process of gasification of sewage sludge generates by-products, which may be contaminated with toxic and hazardous substances, both organic and inorganic. It is therefore important to assess the environmental risk associated with this type of waste. The feasibility of using an ecotoxicological tests for this purpose was determined in the presented study. The applied tests contained indicator organisms belonging to various biological groups (bacteria, crustaceans, plants). The subject of the study were solid (ash, char) and liquid (tar) by-products generated during gasification (in a fixed bed reactor) of dried sewage sludge from various wastewater treatment systems. The tested samples were classified based on their toxic effect. The sensitivity of the indicator organisms to the tested material was determined. In-house procedures for the preparation for toxicity analysis of both sewage sludge and by-products generated during the gasification were presented. The scope of work also included the determination of the effect of selected process parameters (temperature, amount of gasifying agent) on the toxicity of gasification by-products depending on the sewage sludge source. It was shown that both the type of sewage sludge and the parameters of the gasification process affects the toxicity of the by-products of gasification. However, the results of toxicity studies also depend on the type of ecotoxicological test used, which is associated with a different sensitivity of the indicator organisms. Nevertheless, it may be concluded that the by-products formed during the gasification of the low toxicity sewage sludge can be regarded as non-toxic or low toxic. However, the results analysis of the gasification of the toxic sludge were not conclusive, which leads to further research needs in this area. PMID:25827844

  12. TOXIC SUBSTANCES FROM COAL COMBUSTION-A COMPREHENSIVE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    C.L. Senior; F. Huggins; G.P. Huffman; N. Shah; N. Yap; J.O.L. Wendt; W. Seames; M.R. Ames; A.F. Sarofim; S. Swenson; J.S. Lighty; A. Kolker; R. Finkelman; C.A. Palmer; S.J. Mroczkowski; J.J. Helble; R. Mamani-Paco; R. Sterling; G. Dunham; S. Miller

    2001-06-30

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the National Energy Technology Laboratory (NETL), the Electric Power Research Institute, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NOx combustion systems, and new power generation plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). The work discussed in this report covers the Phase II program. Five coals were studied (three in Phase I and two new ones in Phase II). In this work UK has used XAFS and Moessbauer spectroscopies to characterize elements in project coals. For coals, the principal use was to supply direct information about certain hazardous and other key elements (iron) to complement the more complete indirect investigation of elemental modes of occurrence being carried out by colleagues at USGS. Iterative selective leaching using ammonium acetate, HCl, HF, and HNO3, used in conjunction with mineral identification/quantification, and microanalysis of individual mineral grains, has allowed USGS to delineate modes of occurrence for 44 elements. The Phase II coals show rank-dependent systematic differences in trace-element modes of occurrence. The work at

  13. Toxic substances from coal combustion -- A comprehensive assessment

    Energy Technology Data Exchange (ETDEWEB)

    C.L. Senior; T. Panagiotou; F.E. Huggins; G.P. Huffman; N. Yap; J.O.L. Wendt; W. Seames; M.R. Ames; A.F Sarofim; J. Lighty; A. Kolker; R. Finkelman; C.A. Palmer; S.J. Mroczkowsky; J.J. Helble; R. Mamani-Paco

    1999-11-01

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the Federal Energy Technology Center (FETC), the Electric Power Research Institute, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NOx combustion systems, and new power generation plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). This report covers the reporting period from 1 July 1999 to 30 September 1999. During this period the MIT INAA procedures were revised to improve the quality of the analytical results. Two steps have been taken to reduce the analytical errors. A new nitric acid leaching procedure, modified from ASTM procedure D2492, section 7.3.1 for determination of pyritic sulfur, was developed by USGS and validated. To date, analytical results have been returned for all but the last complete round of the four-step leaching procedure. USGS analysts in Denver have halted development of the cold vapor atomic fluorescence technique for mercury analysis procedure in favor of a new direct analyzer for Hg that the USGS is in the process of acquiring. Since early June, emphasis at USGS has been placed on microanalysis of clay minerals in project coals in

  14. Cumulative assessment of persistent organic pollutant toxicity in vivo

    OpenAIRE

    Westerholm, Emma

    2011-01-01

    Humans are continuously exposed to a multitude of compounds present in the environment and in food. A major challenge in risk assessment is to determine the degree of exposure to multiple chemicals and the hazards associated with such combined exposure. The simultaneous exposure to persistent organic pollutants (POPs), such as dioxins and dioxin-like (DL) compounds, polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), is one example of a complex group of chemicals whic...

  15. Human toxicity as a criterion in the environmental assessment of products

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Olsen, Stig Irving; Wenzel, Henrik

    1998-01-01

    . The transfer efficiency is modelled in a standard scenario for indirect exposure of human beings through intake of fish, plants, meat and dairy products. The effect analysis consists in the determination of the highest oral dose or air concentration that is expected to cause no effects in human beings through...... of the potential contribution to toxicity against the potential contributions to other environmental effect types.......As part of a life cycle assessment methodology methods are developed for the semiquantitative screening and for the quantitative assessment of potential contributions to toxicity towards human beings through exposure in the environment to emissions occurring during the life cycle of a product...

  16. Assessment of combined toxicity of heavy metals from industrial wastewaters on Photobacterium phosphoreum T3S

    Science.gov (United States)

    Zeb, BibiSaima; Ping, Zheng; Mahmood, Qaisar; Lin, Qiu; Pervez, Arshid; Irshad, Muhammad; Bilal, Muhammad; Bhatti, Zulfiqar Ahmad; Shaheen, Shahida

    2016-02-01

    This research work is focusing on the toxicities of heavy metals of industrial origin to anaerobic digestion of the industrial wastewater. Photobacterium phosphoreum T3S was used as an indicator organism. The acute toxicities of heavy metals on P. phosphoreum T3S were assessed during 15-min half inhibitory concentration (IC50) as indicator at pH 5.5-6. Toxicity assays involved the assessment of multicomponent mixtures using TU and MTI approaches. The results of individual toxicity indicated that the toxicity of Cd, Cu and Pb on P. phosphoreum increased with increasing concentrations and there was a linear correlation. The 15-min IC50 values of Cd, Cu and Pb were 0.537, 1.905 and 1.231 mg/L, respectively, and their toxic order was Cd > Pb > Cu. The combined effects of Cd, Cu and Pb were assayed by equivalent concentration mixing method. The results showed that the combined effects of Cd + Cu, Cd + Pb, Cu + Pb, Cd + Cu + Pb were antagonistic, antagonistic and partly additive. The combined effect of three heavy metals was partly additive.

  17. Aquatic toxicity assessment of esters towards the Daphnia magna through PCA-ANFIS.

    Science.gov (United States)

    Asadollahi-Baboli, M

    2013-10-01

    The widespread production of esters combined with their ability to migrate in different compartments, makes their environmental toxicity important. In this background, the multivariate image analysis-quantitative structure-toxicity relationship (MIA-QSTR) method coupled to principal component analysis-adaptive neuro-fuzzy inference systems (PCA-ANFIS) was applied to assess the toxicity of esters to Daphnia magna. In MIA-QSTR, pixels of chemical structures (2D images) stand for descriptors, and structural changes account for the variance in toxicities. The ANFIS procedure was capable of correlating the inputs (PCA scores) with the toxicities accurately. The PCA-ANFIS also was statistically validated for its predictive power using cross-validation, applicability domain and Y-scrambling evaluation procedures. The satisfactory results (R p (2) = 0.926, Q LOO (2) = 0.887, R L25%O (2) = 0.843, RMSELOO = 0.320 and RMSEL25%O = 0.379) suggests that the QSTR model could be proposed as an alternative method for aquatic toxicity assessment of esters allowing possible application in the European Union regulation REACH. PMID:23884170

  18. Assessing 20th century climate-vegetation feedbacks of land-use change and natural vegetation dynamics in a fully coupled vegetation-climate model

    NARCIS (Netherlands)

    Strengers, B.J.; Müller, C.; Schaeffer, M.; Haarsma, R.J.; Severijns, C.; Gerten, D.; Schaphoff, S.; Houdt, Van den R.; Oostenrijk, R.

    2010-01-01

    This study describes the coupling of the dynamic global vegetation model (DGVM), Lund–Potsdam–Jena Model for managed land (LPJmL), with the general circulation model (GCM), Simplified Parameterizations primitivE Equation DYnamics model (SPEEDY), to study the feedbacks between land-use change and nat

  19. Health Risk Assessment of Pesticide Residues via Dietary Intake of Market Vegetables from Dhaka, Bangladesh

    Directory of Open Access Journals (Sweden)

    Md. Shakhaoat Hossain

    2013-02-01

    Full Text Available The present study was designed to assess the health risk of pesticide residues via dietary intake of vegetables collected from four top agro-based markets of Dhaka, Bangladesh. High performance liquid chromatography with a photo diode array detector (HPLC-PDA was used to determine six organophosphorus (chlorpyrifos, fenitrothion, parathion, ethion, acephate, fenthion, two carbamate (carbaryl and carbofuran and one pyrethroid (cypermethrin pesticide residues in twelve samples of three common vegetables (tomato, lady’s finger and brinjal. Pesticide residues ranged from below detectable limit (<0.01 to 0.36 mg/kg. Acephate, chlorpyrifos, ethion, carbaryl and cypermethrin were detected in only one sample, while co-occurrence occurred twice for fenitrothion and parathion. Apart from chlorpyrifos in tomato and cypermethrin in brinjal, all pesticide residues exceeded the maximum residue limit (MRL. Hazard risk index (HRI for ethion (10.12 and carbaryl (1.09 was found in lady’s finger and tomato, respectively. Rest of the pesticide residues were classified as not a health risk. A continuous monitoring and strict regulation should be enforced regarding control of pesticide residues in vegetables and other food commodities.

  20. The assessment of vegetative and functional symptoms in fibromyalgia patients: the tropisetron experience.

    Science.gov (United States)

    Kohnen, R; Färber, L; Späth, M

    2004-01-01

    Vegetative and functional symptoms are, besides pain and tenderness of tender points, considered as additional information for the diagnosis of fibromyalgia (FM). In clinical trials, vegetative and functional symptoms have been included for selection of patients (e.g. sleep disturbances) and as secondary outcome parameters. Despite the relevance of these symptoms, no validated method is currently available but symptom lists are ad hoc developed by investigators. In this manuscript, data from a published double blind, randomised study are reanalysed which compared oral therapy over 10 days with 5 mg, 10 mg, and 15 mg to placebo in FM patients. This study applied a list of 17 vegetative and functional symptoms, which had to be scored by the patients by use of a 4-point severity scale (0 = none to 3 = severe). Factor analysis of the baseline data from 195 patients suggested to separate 6 sub-scales: Cardiovascular, gastrointestinal, psychiatric (sleep disturbance), nervous, autonomic system, and general disorders. Sleep disturbances, general symptoms (morning stiffness, fatigue) and autonomic symptoms (cold extremities, hyperhidrosis) were most severe in intensity. Analysis of sensitivity for treatment effects made use of differences between placebo and 5 mg tropisetron in changes between baseline and final assessment of the tropisetron trial. While, on the item level, differences in favour of tropisetron could only be demonstrated for sleep disorders, on the sub-scale level, also favourable effects of tropisetron could be shown for cardiovascular and nervous system complaints and, as a tendency, for general symptoms. On the other side, the sub-scale score of gastrointestinal symptoms worsened under tropisetron whilst it improved under placebo which effect was due to side effects of the active treatment. It is concluded that symptom clusters like sub-scales of a list of vegetative and functional symptoms will be more suitable for diagnostic purposes and evaluation of

  1. TOXIC SUBSTANCES FROM COAL COMBUSTION-A COMPREHENSIVE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    C.L. Senior; F. Huggins; G.P. Huffman; N. Shah; N. Yap; J.O.L. Wendt; W. Seames; M.R. Ames; A.F. Sarofim; S. Swenson; J.S. Lighty; A. Kolker; R. Finkelman; C.A. Palmer; S.J. Mroczkowski; J.J. Helble; R. Mamani-Paco; R. Sterling; G. Dunham; S. Miller

    2001-06-30

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the National Energy Technology Laboratory (NETL), the Electric Power Research Institute, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NOx combustion systems, and new power generation plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). The work discussed in this report covers the Phase II program. Five coals were studied (three in Phase I and two new ones in Phase II). In this work UK has used XAFS and Moessbauer spectroscopies to characterize elements in project coals. For coals, the principal use was to supply direct information about certain hazardous and other key elements (iron) to complement the more complete indirect investigation of elemental modes of occurrence being carried out by colleagues at USGS. Iterative selective leaching using ammonium acetate, HCl, HF, and HNO3, used in conjunction with mineral identification/quantification, and microanalysis of individual mineral grains, has allowed USGS to delineate modes of occurrence for 44 elements. The Phase II coals show rank-dependent systematic differences in trace-element modes of occurrence. The work at

  2. The development of laboratory methods for assessing the efficacy and toxicity of oil spill bioremediation agents

    International Nuclear Information System (INIS)

    Environment Canada has recently developed interim guidelines and methods for a screening-level laboratory evaluation of the efficacy and toxicity of oil spill bioremediation agents (OSBAs) or products. Ten different OSBAs have been tested to aid in protocol validation and assessment. The efficacy of each OSBA is assessed by comparing its ability to bring about changes in the chemical composition of a standard test oil with that obtained using a standard solution of nutrients and/or a standard mixture of hydrocarbon degrading bacteria. The efficacy tests involve the use of the shaker flask incubation technique using either a marine or a fresh water medium. The aquatic toxicity of each OSBA is assessed by measuring its capacity to cause adverse toxic effects on selected species of aquatic organisms. To date, the toxicity assessments have utilized rainbow trout and daphnid acute lethality tests and Microtox. OSBAs which satisfy the requirements and meet the criteria set in the guidelines are considered to have potential application for their intended use. The results from the testing and other data submitted will be made available to various operational and spill response personnel to assist them in assessing the conditions and acceptability for use of that product in response to an oil spill in the environment. 5 refs., 5 figs

  3. Evaluation of methods for assessing toxicity of oil spill treating agents

    Energy Technology Data Exchange (ETDEWEB)

    Lumley, T.C.; Hollebone, B.P. [Environment Canada, Ottawa, ON (Canada); Harrison, S. [SAIC Canada, Ottawa, ON (Canada)

    2007-07-01

    The first counter-measure considered during an oil spill is the mechanical removal of the spilled oil, but this rarely collects more than 20 per cent of the spilled oil. When mechanical means are insufficient, it is advisable to use spill treating agents (STAs). The potential impact of STAs on the environment is estimated by assessing their in-vitro toxicity to sensitive or sentinel organisms. The typical endpoint in animal exposure models is acute lethality LC{sub 50}, which is the concentration that will be fatal to 50 per cent of the test population. The range of STAs include dispersants; shoreline washing agents; de-emulsifiers or emulsion inhibitors; herding agents; recovery agents; solidifiers or gelling agents; biodegradation agents; and, sinking agents. However, a thorough understanding of the overall toxicity of the agent to the environment must be determined along with the net environmental benefit. The agents must undergo rigorous toxicity evaluations to meet the requirements of the New Substances Notification or Significant New Activity Notification sections of the Canadian Environmental Protection Act of 1999. Environment Canada's guidelines for the use and acceptability of dispersants also address toxicity issues. In particular, emphasis has been on evaluating toxicity by the 96-hour rainbow trout lethality test. This paper presented challenges to the current test protocols and recommended that Environment Canada's guidelines for the use of oil STAs should be modified to include a broader definition of toxicity. The toxicity of a dispersant should be less than the toxicity of the water soluble fraction of an oil slick. However, sublethal effects of dispersant exposure, such as endocrine disruption, organ toxicity, mutagenicity and geotoxicity must be better understood. It was argued that testing on one fish species in an enclosed system does not adequately address a diverse marine environment. It was recommended that testing procedures

  4. Indicators for human toxicity in Life Cycle Impact Assessment

    DEFF Research Database (Denmark)

    Krewitt, Wolfram; Pennington, David W.; Olsen, Stig Irving;

    2002-01-01

    The main objectives of this task group under SETAC-Europe’s Second Working Group on Life Cycle Impact Assessment (LCIA-WIA2) were to identify and discuss the suitability of toxicological impact measures for human health for use in characterization in LCIA. The current state of the art of defining......, as well as potency. Quantitative severity-based indicators yield measures in terms of Years of Life Lost (YOLL), Disability Adjusted Life Years (DALY), Quality Adjusted Life Years (QALY) and other similar measures. DALYs and QALYs are examples of approaches that attempt to account for both years of life...... lost (mortality) and years of impaired life (morbidity). Qualitative severity approaches tend to arrange potency-based indicators in categories, avoiding the need to quantitatively express differences in severity. Based on the proposed criteria and current state of the knowledge, toxicological potency...

  5. A New In Vivo Model System to Assess the Toxicity of Semiconductor Nanocrystals

    Directory of Open Access Journals (Sweden)

    Angela Tino

    2011-01-01

    Full Text Available In the emerging area of nanotechnology, a key issue is related to the potential impacts of the novel nanomaterials on the environment and human health, so that this technology can be used with minimal risk. Specifically designed to combine on a single structure multipurpose tags and properties, smart nanomaterials need a comprehensive characterization of both chemicophysical properties and adequate toxicological evaluation, which is a challenging endeavour; the in vitro toxicity assays that are often employed for nanotoxicity assessments do not accurately predict in vivo response. To overcome these limitations and to evaluate toxicity characteristics of cadmium telluride quantum dots in relation to surface coatings, we have employed the freshwater polyp Hydra vulgaris as a model system. We assessed in vivo acute and sublethal toxicity by scoring for alteration of morphological traits, population growth rates, and influence on the regenerative capabilities providing new investigation clues for nanotoxicology purposes.

  6. An integrated assessment of the impact of precipitation and groundwater on vegetation growth in arid and semiarid areas

    CERN Document Server

    Zhu, Lin; Dai, Zhenxue; Xu, Tingbao; Su, Xiaosi

    2014-01-01

    Increased demand for water resources together with the influence of climate change has degraded water conditions which support vegetation in many parts of the world, especially in arid and semiarid areas. This study develops an integrated framework to assess the impact of precipitation and groundwater on vegetation growth in the Xiliao River Plain of northern China. The integrated framework systematically combines remote sensing technology with water flow modeling in the vadose zone and field data analysis. The vegetation growth is quantitatively evaluated with the remote sensing data by the Normalized Difference Vegetation Index (NDVI) and the simulated plant water uptake rates. The correlations among precipitation, groundwater depth and NDVI are investigated by using Pearson correlation equations. The results provide insights for understanding interactions between precipitation and groundwater and their contributions to vegetation growth. Strong correlations between groundwater depth, plant water uptake and...

  7. Physiologic assessment of fetal compromise: biomarkers of toxic exposure

    Energy Technology Data Exchange (ETDEWEB)

    Longo, L.D.

    1987-10-01

    Understanding the physiologic and endocrinologic basis of fetal development is a major goal of perinatal biology. During the past decade a number of technological developments have allowed more precise evaluation of the fetus in utero and diagnosis of abnormalities. Despite these methodological achievements, however, there are no specific biological markers currently available to indicate that exposure to a given xenobiotic is associated with a cellular, subcellular, or pharmacodynamic event. This paper evaluates the following issues: what are some of the unique physiologic and endocrinologic features of the fetal milieu interieur. What problems are peculiar to fetal assessment. What are some examples of validated biomarkers and their applicability. What promising biomarkers are on the horizon. How may molecular probes be of value as biological markers of fetal compromise. What are some of the major research gaps and needs, and how should research priorities be set. Some of these topics are addressed. Moreover, the more general role(s) that various diagnostic methods and biological markers can have in an understanding of the regulation of fetal growth and differentiation and the role of xenobiotics in affecting the normal course of events are discussed.

  8. LIFE CYCLE BIOASSAY FOR ASSESSMENT OF THE EFFECTS OF TOXIC CHEMICALS USING RAPID CYCLING OF BRASSICA

    Science.gov (United States)

    Initial evaluation of a new plant life cycle bioassay for the assessment of the effects of toxic chemicals is presented. he bioassay features a rapid cycling Brassica species that can complete its life cycle in as little as 36 days. he herbicide dalapon (2,2 dichloropropionic aci...

  9. Mode of Action Frameworks in Toxicity Testing and Chemical Risk Assessment

    NARCIS (Netherlands)

    Meek, B.

    2009-01-01

    Recently, legislative mandates worldwide are requiring systematic consideration of much larger numbers of chemicals. This necessitates more efficient and effective toxicity testing, as a basis to be more predictive in a risk assessment context. This in turn requires much more emphasis early in the d

  10. TECHNICAL CHALLENGES ASSOCIATED WITH ASSESSING THE IN VITRO PULMONARY TOXICITY OF CARBON NANOTUBES

    Science.gov (United States)

    Nanotechnology continues to produce a large number of diverse engineered nanomaterials (NMs) with novel physicochemical properties for a variety of applications. Test methods that accurately assess/predict the toxicity of NMs are critically needed and it is unclear whether curren...

  11. Toxicity assessment of Titanium Dioxide and Cerium Oxide nanoparticles in Arabidopsis thaliana L.

    Science.gov (United States)

    The production and applications of nanoparticles (NP) in diverse fields has steadily increased in recent decades; however, knowledge about risks of NP to human health and ecosystems is still scarce. In this study, we assessed potential toxicity of two commercially used engineere...

  12. Toxicity Assessment of Six Titanium Dioxide Nanoparticles in Human Epidermal Keratinocytes

    Science.gov (United States)

    Toxicity Assessment of Six Titanium Dioxide Nanoparticles in Human Epidermal Keratinocytes Nanoparticle uptake in cells may be an important determinant of their potential cytotoxic and inflammatory effects. Six commercial TiO2 NP (A=Alfa Aesar,10nm, A*=Alfa Aesar 32nm, B=P25 27...

  13. Development and application of a multimetal multibiotic ligand model for assessing aquatic toxicity of metal mixtures.

    Science.gov (United States)

    Santore, Robert C; Ryan, Adam C

    2015-04-01

    A multimetal, multiple binding site version of the biotic ligand model (mBLM) has been developed for predicting and explaining the bioavailability and toxicity of mixtures of metals to aquatic organisms. The mBLM was constructed by combining information from single-metal BLMs to preserve compatibility between the single-metal and multiple-metal approaches. The toxicities from individual metals were predicted by assuming additivity of the individual responses. Mixture toxicity was predicted based on both dissolved metal and mBLM-normalized bioavailable metal. Comparison of the 2 prediction methods indicates that metal mixtures frequently appear to have greater toxicity than an additive estimation of individual effects on a dissolved metal basis. However, on an mBLM-normalized basis, mixtures of metals appear to be additive or less than additive. This difference results from interactions between metals and ligands in solutions including natural organic matter, processes that are accounted for in the mBLM. As part of the mBLM approach, a technique for considering variability was developed to calculate confidence bounds (called response envelopes) around the central concentration-response relationship. Predictions using the mBLM and response envelope were compared with observed toxicity for a number of invertebrate and fish species. The results show that the mBLM is a useful tool for considering bioavailability when assessing the toxicity of metal mixtures.

  14. Assessment of toxic potential of Cerrado fruit seeds using Artemia salina bioassay

    Directory of Open Access Journals (Sweden)

    Raíza Cavalcante Fonseca

    2013-06-01

    Full Text Available Artemia salina bioassay was used to assess toxicity of seeds and kernels of Brazilian fruits from cerrado (central high plains region and other inner regions of the country. Water extracts of the kernels were filtered and added to Artemia cultures containing ten individuals per mL. Dose - response curves were constructed, and LD50 values were calculated. Pure potassium cyanide standard was used to draw a calibration curve for comparison to detect the presence of cyanide in the samples tested. Extracts of the seeds of araticum, mangaba, cagaita, jatobá, and tucumã were found toxic to Artemia salina, and some of the dose - response curves were very similar in shape to those obtained with pure potassium cyanide standards, while the samples of baru, cajá-manga, siriguela, trauma, and veludo showed no toxicity at all. The Guignard test, specific for cyanide detection, showed negative results in all toxic samples, suggesting the presence of other toxic compounds rather than cyanide. The comparison of araticum dose - response curve with those of other annonaceous fruits suggests the presence acetogenins as the main toxic compounds in the seeds. These results could be useful to prevent poisoning by industrial derivatives of the fruits studied.

  15. Vulnerability assessment and protective effects of coastal vegetation during the 2004 Tsunami in Sri Lanka

    Science.gov (United States)

    Kaplan, M.; Renaud, F. G.; Lüchters, G.

    2009-08-01

    The tsunami of December 2004 caused extensive human and economic losses along many parts of the Sri Lankan coastline. Thanks to extensive national and international solidarity and support in the aftermath of the event, most people managed to restore their livelihoods completely but some households did not manage to recover completely from the impacts of the event. The differential in recovery highlighted the various vulnerabilities and coping capacities of communities exposed to the tsunami. Understanding the elements causing different vulnerabilities is crucial to reducing the impact of future events, yet capturing them comprehensively at the local level is a complex task. This research was conducted in a tsunami-affected area in southwestern Sri Lanka to evaluate firstly the role of coastal vegetation in buffering communities against the tsunami and secondly to capture the elements of vulnerability of affected communities. The area was chosen because of its complex landscape, including the presence of an inlet connecting the Maduganga estuary with the sea, and because of the presence of remaining patches of coastal vegetation. The vulnerability assessment was based on a comprehensive vulnerability framework and on the Sustainable Livelihoods Framework in order to detect inherent vulnerabilities of different livelihood groups. Our study resulted in the identification of fishery and labour-led households as the most vulnerable groups. Unsurprisingly, analyses showed that damages to houses and assets decreased quickly with increasing distance from the sea. It could also be shown that the Maduganga inlet channelled the energy of the waves, so that severe damages were observed at relatively large distances from the sea. Some reports after the tsunami stated that mangroves and other coastal vegetation protected the people living behind them. Detailed mapping of the coastal vegetation in the study area and subsequent linear regression revealed significant differences

  16. River basin soil-vegetation condition assessment applying mathematic simulation methods

    Science.gov (United States)

    Mishchenko, Natalia; Trifonova, Tatiana; Shirkin, Leonid

    2013-04-01

    Meticulous attention paid nowadays to the problem of vegetation cover productivity changes is connected also to climate global transformation. At the same time ecosystems anthropogenic transformation, basically connected to the changes of land use structure and human impact on soil fertility, is developing to a great extent independently from climatic processes and can seriously influence vegetation cover productivity not only at the local and regional levels but also globally. Analysis results of land use structure and soil cover condition influence on river basin ecosystems productive potential is presented in the research. The analysis is carried out applying integrated characteristics of ecosystems functioning, space images processing results and mathematic simulation methods. The possibility of making permanent functional simulator defining connection between macroparameters of "phytocenosis-soil" system condition on the basis of basin approach is shown. Ecosystems of river catchment basins of various degrees located in European part of Russia were chosen as research objects. For the integrated assessment of ecosystems soil and vegetation conditions the following characteristics have been applied: 1. Soil-productional potential, characterizing the ability of natural and natural-anthropogenic ecosystem in certain soil-bioclimatic conditions for long term reproduction. This indicator allows for specific phytomass characteristics and ecosystem produce, humus content in soil and bioclimatic parameters. 2. Normalized difference vegetation index (NDVI) has been applied as an efficient, remotely defined, monitoring indicator characterizing spatio-temporal unsteadiness of soil-productional potential. To design mathematic simulator functional simulation methods and principles on the basis of regression, correlation and factor analysis have been applied in the research. Coefficients values defining in the designed static model of phytoproductivity distribution has been

  17. Assessment of heavy metal pollution in vegetables and relationships with soil heavy metal distribution in Zhejiang province, China.

    Science.gov (United States)

    Ye, Xuezhu; Xiao, Wendan; Zhang, Yongzhi; Zhao, Shouping; Wang, Gangjun; Zhang, Qi; Wang, Qiang

    2015-06-01

    There are increasing concerns on heavy metal contaminant in soils and vegetables. In this study, we investigated heavy metal pollution in vegetables and the corresponding soils in the main vegetable production regions of Zhejiang province, China. A total of 97 vegetable samples and 202 agricultural soil samples were analyzed for the concentrations of Cd, Pb, As, Hg, and Cr. The average levels of Cd, Pb, and Cr in vegetable samples [Chinese cabbage (Brassica campestris spp. Pekinensis), pakchoi (Brassica chinensis L.), celery (Apium graveolens), tomato (Lycopersicon esculentum), cucumber (Colletotrichum lagenarium), cowpea (Vigna unguiculata), pumpkin (Cucurbita pepo L.), and eggplant (Solanum melongena)] were 0.020, 0.048, and 0.043 mg kg(-1), respectively. The Pb and Cr concentrations in all vegetable samples were below the threshold levels of the Food Quality Standard (0.3 and 0.5 mg kg(-1), respectively), except that two eggplant samples exceeded the threshold levels for Cd concentrations (0.05 mg kg(-1)). As and Hg contents in vegetables were below the detection level (0.005 and 0.002 mg kg(-1), respectively). Soil pollution conditions were assessed in accordance with the Chinese Soil Quality Criterion (GB15618-1995, Grade II); 50 and 68 soil samples from the investigated area exceeded the maximum allowable contents for Cd and Hg, respectively. Simple correlation analysis revealed that there were significantly positive correlations between the metal concentrations in vegetables and the corresponding soils, especially for the leafy and stem vegetables such as pakchoi, cabbage, and celery. Bio-concentration factor values for Cd are higher than those for Pb and Cr, which indicates that Cd is more readily absorbed by vegetables than Pb and Cr. Therefore, more attention should be paid to the possible pollution of heavy metals in vegetables, especially Cd. PMID:26013654

  18. LCA of contaminated site remediation - integration of site-specific impact assessment of local toxic impacts

    DEFF Research Database (Denmark)

    Lemming, Gitte; Hauschild, Michael Zwicky; Chambon, Julie Claire Claudia;

    2011-01-01

    impacts have typically been assessed using site-generic characterization models representing a continental scale and excluding the groundwater compartment. Soil contaminants have therefore generally been assigned as emissions to surface soil or surface water compartments. However, such site...... of bioremediation scenarios (86-98 % of the human toxicity impacts at Site 1). The inclusion of primary impacts in the environmental assessment of remediation alternatives gives a more complete basis for comparison of technologies with substantially different timeframes and efficiencies....

  19. Reference manual for toxicity and exposure assessment and risk characterization. CERCLA Baseline Risk Assessment

    International Nuclear Information System (INIS)

    The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, 1980) (CERCLA or Superfund) was enacted to provide a program for identifying and responding to releases of hazardous substances into the environment. The Superfund Amendments and Reauthorization Act (SARA, 1986) was enacted to strengthen CERCLA by requiring that site clean-ups be permanent, and that they use treatments that significantly reduce the volume, toxicity, or mobility of hazardous pollutants. The National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (USEPA, 1985; USEPA, 1990) implements the CERCLA statute, presenting a process for (1) identifying and prioritizing sites requiring remediation and (2) assessing the extent of remedial action required at each site. The process includes performing two studies: a Remedial Investigation (RI) to evaluate the nature, extent, and expected consequences of site contamination, and a Feasibility Study (FS) to select an appropriate remedial alternative adequate to reduce such risks to acceptable levels. An integral part of the RI is the evaluation of human health risks posed by hazardous substance releases. This risk evaluation serves a number of purposes within the overall context of the RI/FS process, the most essential of which is to provide an understanding of ''baseline'' risks posed by a given site. Baseline risks are those risks that would exist if no remediation or institutional controls are applied at a site. This document was written to (1) guide risk assessors through the process of interpreting EPA BRA policy and (2) help risk assessors to discuss EPA policy with regulators, decision makers, and stakeholders as it relates to conditions at a particular DOE site

  20. Reference manual for toxicity and exposure assessment and risk characterization. CERCLA Baseline Risk Assessment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, 1980) (CERCLA or Superfund) was enacted to provide a program for identifying and responding to releases of hazardous substances into the environment. The Superfund Amendments and Reauthorization Act (SARA, 1986) was enacted to strengthen CERCLA by requiring that site clean-ups be permanent, and that they use treatments that significantly reduce the volume, toxicity, or mobility of hazardous pollutants. The National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (USEPA, 1985; USEPA, 1990) implements the CERCLA statute, presenting a process for (1) identifying and prioritizing sites requiring remediation and (2) assessing the extent of remedial action required at each site. The process includes performing two studies: a Remedial Investigation (RI) to evaluate the nature, extent, and expected consequences of site contamination, and a Feasibility Study (FS) to select an appropriate remedial alternative adequate to reduce such risks to acceptable levels. An integral part of the RI is the evaluation of human health risks posed by hazardous substance releases. This risk evaluation serves a number of purposes within the overall context of the RI/FS process, the most essential of which is to provide an understanding of ``baseline`` risks posed by a given site. Baseline risks are those risks that would exist if no remediation or institutional controls are applied at a site. This document was written to (1) guide risk assessors through the process of interpreting EPA BRA policy and (2) help risk assessors to discuss EPA policy with regulators, decision makers, and stakeholders as it relates to conditions at a particular DOE site.

  1. Health assessment of gasoline and fuel oxygenate vapors: reproductive toxicity assessment.

    Science.gov (United States)

    Gray, Thomas M; Steup, David; Roberts, Linda G; O'Callaghan, James P; Hoffman, Gary; Schreiner, Ceinwen A; Clark, Charles R

    2014-11-01

    Vapor condensates of baseline gasoline (BGVC), or gasoline-blended with methyl tertiary butyl ether (G/MTBE), ethyl t-butyl ether (G/ETBE), t-amyl methyl ether (G/TAME), diisopropyl ether (G/DIPE), ethanol (G/EtOH), or t-butyl alcohol (G/TBA) were evaluated for reproductive toxicity in rats at target concentrations of 2000, 10,000, or 20,000mg/m(3), 6h/day, 7days/week. BGVC and G/MTBE were assessed over two generations, the others for one generation. BGVC and G/MTBE F1 offspring were evaluated for neuropathology and changes in regional brain glial fibrillary acidic protein content. No neurotoxicity was observed. Male kidney weight was increased consistent with light hydrocarbon nephropathy. In adult rats, decreased body weight gain and increased liver weight were seen. Spleen weight decreased in adults and pups exposed to G/TBA. No pathological changes to reproductive organs occurred in any study. Decreased food consumption was seen in G/TAME lactating females. Transient decreases in G/TAME offspring weights were observed during lactation. Except for a minor increase in time to mating in G/TBA which did not affect other reproductive parameters, there were no adverse reproductive findings. The NOAEL for reproductive and offspring parameters was 20,000mg/m(3) for all vapor condensates except for lower offspring NOAELs of 10,000mg/m(3) for G/TBA and 2000mg/m(3) for G/TAME. PMID:24813181

  2. Toxicity assessing for chlorpyrifos-contaminated soil with three different earthworm test methods

    Institute of Scientific and Technical Information of China (English)

    ZHOU Shi-ping; DUAN Chang-qun; FU Hui; CHEN Yu-hui; WANG Xue-hua; YU Ze-fen

    2007-01-01

    Earthworm toxicity tests are useful tools for terrestrial risk assessment but require a hierarchy of test designs that differ in effect levels (behavior, sublethal, lethal). In this study, the toxicity of chlorpyrifos contaminated soil on earthworms was assessed. In addition to the acute and chronic tests, an avoidance response test was applied. Earthworms were exposed to sublethal and lethal concentration of chlorpyrifos, and evaluated for acute toxicity, growth, fecundity and avoidance response after a certain exposure period. The test methods covered all important ecological relevant endpoints (acute, chronic, behavioral). Concentration of 78.91 mg/kg, chlorpyrifos caused significant toxic effects in all test methods, but at lower test concentrations, only significant chronic toxic effects could be observed. In the present study, chlorpyrifos had adverse effect on growth and fecundity in earthworm exposed to 5 mg/kg chlorpyrifos after eight weeks. The avoidance response test, however, showed significant repellent effects concentration of 40 mg/kg chlorpyrifos. For chlorpyrifos, concentration affecting avoidance response was far greater than growth and fecundity, it seemed likely that earthworms were not able to escape from pesticide-contaminated soil into the clean soil in field and hence were exposed continuously to elevated concentrations of pesticides.

  3. Toxicity assessment of ethanol extract of Solanum villosum (Mill on wistar albino rats.

    Directory of Open Access Journals (Sweden)

    Venkatesh R

    2014-07-01

    Full Text Available Purpose: To evaluate the potential toxicity of ethanol extract of the medicinal plant Solanum villosum (Mill. Methods: Ethanol extract of S. villosum administered orally at ranges of doses 100, 200, 400, 600 and 800 mg/kg/bw to assess its impact on biochemical indices of Wistar albino rats. Hematological profile, biochemical assays, antioxidant and lipid peroxidation assays were compared between control and experimental animals. An acute toxicity test was performed in rats at different concentration of ethanol extract of S. villosum in order to establish the approximate oral lethal dose (LD 50. Results: No mortality occurred during the two weeks experimental period, in both control and experimental groups. The changes in biochemical parameters were statistically insignificant at p<0.05 levels. The treated rats showed that very less toxic symptoms only after 800 mg/kg/bw. These observations were supported by hematological and liver function markers. Conclusions: The medicinal plant Solanum villosum can be administered orally at a dose range of 200 mg/kg/bw was very effective and without any side effects. Ethanol extract of S. villosum is not toxic and therefore it may be used safely in clinical trials. It is the first documented report about the plant Solanum villosum (Mill in the toxicity assessment study.

  4. Assessments of Drought Impacts on Vegetation in China with the Optimal Time Scales of the Climatic Drought Index.

    Science.gov (United States)

    Li, Zheng; Zhou, Tao; Zhao, Xiang; Huang, Kaicheng; Gao, Shan; Wu, Hao; Luo, Hui

    2015-07-08

    Drought is expected to increase in frequency and severity due to global warming, and its impacts on vegetation are typically extensively evaluated with climatic drought indices, such as multi-scalar Standardized Precipitation Evapotranspiration Index (SPEI). We analyzed the covariation between the SPEIs of various time scales and the anomalies of the normalized difference vegetation index (NDVI), from which the vegetation type-related optimal time scales were retrieved. The results indicated that the optimal time scales of needle-leaved forest, broadleaf forest and shrubland were between 10 and 12 months, which were considerably longer than the grassland, meadow and cultivated vegetation ones (2 to 4 months). When the optimal vegetation type-related time scales were used, the SPEI could better reflect the vegetation's responses to water conditions, with the correlation coefficients between SPEIs and NDVI anomalies increased by 5.88% to 28.4%. We investigated the spatio-temporal characteristics of drought and quantified the different responses of vegetation growth to drought during the growing season (April-October). The results revealed that the frequency of drought has increased in the 21st century with the drying trend occurring in most of China. These results are useful for ecological assessments and adapting management steps to mitigate the impact of drought on vegetation. They are helpful to employ water resources more efficiently and reduce potential damage to human health caused by water shortages.

  5. Monitoring of Pesticide Residues in Fruits and Vegetables and Related Health Risk Assessment in Kumasi Metropolis, Ghana

    OpenAIRE

    Crentsil Kofi Bempah; Archibold Buah-Kwofie; Dzifa Denutsui; Jacob Asomaning; Anita Osei Tutu

    2011-01-01

    The objective of present research study was to assess the concentration of pesticide residues in fruits and vegetables from markets in Kumasi and to generate awareness about the lethal effects of these pesticides on human beings as well as to estimate the potential health risks associated with the pesticide residue with regard to consumers. A total of 350 locally produced fruits and vegetables were purchased from six main markets in Kumasi and analyzed by gas chromatography equipped with elec...

  6. Chemical and biological toxicity assessment of simulated Hanford site low-level waste grouts

    International Nuclear Information System (INIS)

    Defining the potential damage to the biosphere associated with exposure to low-level waste grouting operations at the Hanford Site near Richland, Washington, is difficult and controversial. Combined chemical and biological assessment of grout toxicity is needed to provide information on the potential risks of animal and plant exposure to the grouts. This paper will identify and predict the chemical components of the grout that will have the greatest potential of causing deleterious effects on fish and wildlife indigenous to the Hanford Site. This paper will also determine whether the current grout technology is adequate in controlling toxicant and pollutant releases for regulatory compliance

  7. Toxicovigilance: A new approach for the hazard identification and risk assessment of toxicants in human beings

    International Nuclear Information System (INIS)

    The concept of toxicovigilance encompasses the active detection, validation and follow-up of clinical adverse events related to toxic exposures in human beings. Poison centers are key players in this function as poisoning statistics are essential to define the cause, incidence and severity of poisonings occurring in the general population. In addition, the systematic search for unexpected shifts in the recorded causes of poisonings, e.g., following the introduction of a new product, or change in the formulation or recommended use of an old product, allows for a rapid detection of potential adverse health consequences and the implementation of preventive or corrective measures. However, toxicovigilance is genuinely a medical and not only a statistical approach of human toxicity issues. In contrast to epidemiology, toxicovigilance is based on the in-depth medical assessment of acute or chronic intoxications on an individual basis, which requires detailed information that poison centers can rarely obtain via emergency telephone calls and that epidemiologists cannot collect or process. Validation of this medical information must primarily be based on toxicological expertise to help identify causal links between otherwise unexplained pathological conditions and documented toxic exposures. Thus, toxicovigilance can contribute to hazard identification and risk assessment by providing medically validated data which are often overlooked in the process of risk assessment. So far, very few structured toxicovigilance systems have been set up and hopefully national and international initiatives will bridge this gap in our knowledge of the toxicity of many chemicals and commercial products in human beings

  8. Sustainability assessment of greenhouse vegetable farming practices from environmental, economic, and socio-institutional perspectives in China.

    Science.gov (United States)

    Yang, Lanqin; Huang, Biao; Mao, Mingcui; Yao, Lipeng; Niedermann, Silvana; Hu, Wenyou; Chen, Yong

    2016-09-01

    To provide growing population with sufficient food, greenhouse vegetable production has expanded rapidly in recent years in China and sustainability of its farming practices is a major concern. Therefore, this study assessed the sustainability of greenhouse vegetable farming practices from environmental, economic, and socio-institutional perspectives in China based on selected indicators. The empirical data were collected through a survey of 91 farm households from six typical greenhouse vegetable production bases and analysis of environmental material samples. The results showed that heavy fertilization in greenhouse vegetable bases of China resulted in an accumulation of N, P, Cd, Cu, Pb, and Zn in soil, nutrient eutrophication in irrigation water, and high Cd in some leaf vegetables cultivated in acidic soil. Economic factors including decreased crop yield in conventional farming bases, limited and site-dependent farmers' income, and lack of complete implementation of subsidy policies contributed a lot to adoption of heavy fertilization by farmers. Also, socio-institutional factors such as lack of unified management of agricultural supplies in the bases operated in cooperative and small family business models and low agricultural extension service efficiency intensified the unreasonable fertilization. The selection of cultivated vegetables was mainly based on farmers' own experience rather than site-dependent soil conditions. Thus, for sustainable development of greenhouse vegetable production systems in China, there are two key aspects. First, it is imperative to reduce environmental pollution and subsequent health risks through integrated nutrient management and the planting strategy of selected low metal accumulation vegetable species especially in acidic soil. Second, a conversion of cooperative and small family business models of greenhouse vegetable bases to enterprises should be extensively advocated in future for the unified agricultural supplies

  9. Assessment of a fiber-optic distributed-temperature-sensing system to monitor the thermal dynamics of vegetated roof

    Science.gov (United States)

    Cousiño, J. A.; Hausner, M. B.; Victorero, F.; Bonilla, C.; Gironas, J. A.; Vera, S.; Bustamante, W.; Rojas, V.; Pasten, P.; Suarez, F. I.

    2014-12-01

    Vegetated (green) roofs include a growing media and vegetation layer, and offer a range of benefits such as the reduction of: the heat island effect, rooftop runoff peak flows, roof surface temperatures, energy used for cooling or heating buildings, and noise levels inside infrastructures. Vegetated roofs also offer aesthetic benefits and increase the biodiversity of the urban environment, and are increasingly used in sustainable urban development. Understanding the thermal dynamics of vegetated roofs will make it possible to improve their design and to better assess their impacts on energy efficiency. Here, we evaluate the first vertical high-resolution distributed-temperature-sensing (DTS) system installed in a vegetated roof. This system allows a continuous measurement of the thermal profile within a vegetated roof - going from the interior, upward through the drainage layers and soil substrate of the vegetated roof and ending in the air above the vegetation. Temperatures can be observed as frequently as every 30 s at a spatial resolution on the order of centimeters. This DTS system was installed in the "Laboratory of Vegetal Infrastructure of Buildings" (LIVE - its acronym in Spanish), located in the San Joaquín Campus of the Pontifical Catholic University, Santiago, Chile. The laboratory features 18 experimental modules to investigate different configurations of the vegetated roof layers. The LIVE was designed with the installation of the optical fibers in mind, and the DTS system allows simultaneous monitoring of three or four modules of the LIVE. In this work, we describe the design of this DTS deployment, the calibration metrics obtained using the software provided by the manufacturers, and other calibration algorithms previously developed. We compare the results obtained using single- and double-ended measurements, highlighting strengths and weaknesses of DTS methods. Finally, we present the observations obtained from this biophysical environment

  10. Sustainability assessment of greenhouse vegetable farming practices from environmental, economic, and socio-institutional perspectives in China.

    Science.gov (United States)

    Yang, Lanqin; Huang, Biao; Mao, Mingcui; Yao, Lipeng; Niedermann, Silvana; Hu, Wenyou; Chen, Yong

    2016-09-01

    To provide growing population with sufficient food, greenhouse vegetable production has expanded rapidly in recent years in China and sustainability of its farming practices is a major concern. Therefore, this study assessed the sustainability of greenhouse vegetable farming practices from environmental, economic, and socio-institutional perspectives in China based on selected indicators. The empirical data were collected through a survey of 91 farm households from six typical greenhouse vegetable production bases and analysis of environmental material samples. The results showed that heavy fertilization in greenhouse vegetable bases of China resulted in an accumulation of N, P, Cd, Cu, Pb, and Zn in soil, nutrient eutrophication in irrigation water, and high Cd in some leaf vegetables cultivated in acidic soil. Economic factors including decreased crop yield in conventional farming bases, limited and site-dependent farmers' income, and lack of complete implementation of subsidy policies contributed a lot to adoption of heavy fertilization by farmers. Also, socio-institutional factors such as lack of unified management of agricultural supplies in the bases operated in cooperative and small family business models and low agricultural extension service efficiency intensified the unreasonable fertilization. The selection of cultivated vegetables was mainly based on farmers' own experience rather than site-dependent soil conditions. Thus, for sustainable development of greenhouse vegetable production systems in China, there are two key aspects. First, it is imperative to reduce environmental pollution and subsequent health risks through integrated nutrient management and the planting strategy of selected low metal accumulation vegetable species especially in acidic soil. Second, a conversion of cooperative and small family business models of greenhouse vegetable bases to enterprises should be extensively advocated in future for the unified agricultural supplies

  11. Risk assessment of heavy metals in soils and vegetables around non-ferrous metals mining and smelting sites, Baiyin, China

    Institute of Scientific and Technical Information of China (English)

    LI Yu; WANG Yan-bin; GOU Xin; SU Yi-bing; WANG Gang

    2006-01-01

    A field survey was conducted to investigate the metal and arsenic contamination in soils and vegetables on four villages (Shuichuan (SCH), Beiwan (BWA), Dongwan (DWA) and Wufe (WFE)) located along, Baiyin, China, and to evaluate the possible health risks to local population through foodchain. Results show that the most significantly contaminated soils occurred upstream at SCH where Cd, Cu and As concentrations exceeded maximum allowable concentrations for Chinese agricultural soil. Further downstream the degree of contamination semi-systematically decreased in concentrations of metal. Generally, the leafy vegetables were more heavily contaminated than non-leafy vegetables. Chinese cabbage is the most severely contaminated, the concentrations of Cd exceeded the maximum permit levels (0.05 mg/kg) by 4.5 times. Bio-accumulate factor also shows that an entry of Cd to food chain plants is the greatest potential. Furthermore, the estimated daily intake amounts of the considered toxic elements (Cd, Pb and Cu) from the vegetables grown at SCH and BWA and DWA have exceeded the recommended dietary allowance levels. Thus, the vegetables grown in three villages above, which affected by Baiyin mining and smelting have a health hazard for human consumption.

  12. Toxicity assessment of polycyclic aromatic hydrocarbons in sediments from European high mountain lakes.

    Science.gov (United States)

    Quiroz, Roberto; Grimalt, Joan O; Fernández, Pilar

    2010-05-01

    Sediment quality guidelines and toxic equivalent factors have been used for assessment of the toxicity of sedimentary long-range atmospherically transported polycyclic aromatic hydrocarbons (PAHs) to the organisms living in high mountain European lakes. This method has provided indices that are consistent with experimental studies evaluating in situ sedimentary estrogenic activity or physiological response to AhR binding in fish from the same lakes. All examined lakes in north, central, west, northeast and southeast European mountains have shown sedimentary PAH concentrations that are above thresholds of no effect but only those situated in the southeast lakes district exhibited concentrations above the indices of probable effects. These mountains, Tatras, are also those having PAH concentrations of highest activity for AhR binding. Chrysene+triphenylene, dibenz[a]anthracene, benzo[k]fluoranthene and indeno[1,2,3-cd]pyrene are the main compounds responsible for the observed toxic effects.

  13. Full toxicity assessment of Genkwa Flos and the underlying mechanism in nematode Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Yan Qiao

    Full Text Available Genkwa Flos (GF, the dried flower bud from Daphne genkwa Sieb. et Zucc. (Thymelaeaceae, is a well-known and widely used traditional Chinese medicine. However, we know little about the in vivo mechanism of GF toxicity. Nematode Caenorhabditis elegans has been considered as a useful toxicity assay system by offering a system best suited for asking the in vivo questions. In the present study, we employed the prolonged exposure assay system of C. elegans to perform the full in vivo toxicity assessment of raw-processed GF. Our data show that GF exposure could induce the toxicity on lifespan, development, reproduction, and locomotion behavior. GF exposure not only decreased body length but also induced the formation of abnormal vulva. The decrease in brood size in GF exposed nematodes appeared mainly at day-1 during the development of adult nematodes. The decrease of locomotion behavior in GF exposed nematodes might be due to the damage on development of D-type GABAergic motor neurons. Moreover, we observed the induction of intestinal reactive oxygen species (ROS production and alteration of expression patterns of genes required for development of apical domain, microvilli, and apical junction of intestine in GF exposed nematodes, implying the possible dysfunction of the primary targeted organ. In addition, GF exposure induced increase in defecation cycle length and deficits in development of AVL and DVB neurons controlling the defecation behavior. Therefore, our study implies the usefulness of C. elegans assay system for toxicity assessment from a certain Chinese medicine or plant extract. The observed toxicity of GF might be the combinational effects of oxidative stress, dysfunction of intestine, and altered defecation behavior in nematodes.

  14. Pharmacology-based toxicity assessment: towards quantitative risk prediction in humans.

    Science.gov (United States)

    Sahota, Tarjinder; Danhof, Meindert; Della Pasqua, Oscar

    2016-05-01

    Despite ongoing efforts to better understand the mechanisms underlying safety and toxicity, ~30% of the attrition in drug discovery and development is still due to safety concerns. Changes in current practice regarding the assessment of safety and toxicity are required to reduce late stage attrition and enable effective development of novel medicines. This review focuses on the implications of empirical evidence generation for the evaluation of safety and toxicity during drug development. A shift in paradigm is needed to (i) ensure that pharmacological concepts are incorporated into the evaluation of safety and toxicity; (ii) facilitate the integration of historical evidence and thereby the translation of findings across species as well as between in vitro and in vivo experiments and (iii) promote the use of experimental protocols tailored to address specific safety and toxicity questions. Based on historical examples, we highlight the challenges for the early characterisation of the safety profile of a new molecule and discuss how model-based methodologies can be applied for the design and analysis of experimental protocols. Issues relative to the scientific rationale are categorised and presented as a hierarchical tree describing the decision-making process. Focus is given to four different areas, namely, optimisation, translation, analytical construct and decision criteria. From a methodological perspective, the relevance of quantitative methods for estimation and extrapolation of risk from toxicology and safety pharmacology experimental protocols, such as points of departure and potency, is discussed in light of advancements in population and Bayesian modelling techniques (e.g. non-linear mixed effects modelling). Their use in the evaluation of pharmacokinetics (PK) and pharmacokinetic-pharmacodynamic relationships (PKPD) has enabled great insight into the dose rationale for medicines in humans, both in terms of efficacy and adverse events. Comparable benefits

  15. Inventory of LCIA selection methods for assessing toxic releases. Methods and typology report part B

    DEFF Research Database (Denmark)

    Larsen, Henrik Fred; Birkved, Morten; Hauschild, Michael Zwicky;

    This report describes an inventory of Life Cycle Impact Assessment (LCIA) selection methods for assessing toxic releases. It consists of an inventory of current selection methods and other Chemical Ranking and Scoring (CRS) methods assessed to be relevant for the development of (a) new selection...... characterisation. Selection methods are used within LCIA to select those chemical emissions (mapped in the inventory part of the LCA in question) that are expected to contribute significantly to the characterisation and exclude the insignificant ones. In this way only significant emissions (i.e. the selected ones...

  16. Remote sensing of ecosystem vulnerability: Assessing climate-vegetation-livestock interactions in Mongolia

    Science.gov (United States)

    Kang, S.; Hong, S. Y.

    2015-12-01

    indicator of grazing pressure, while climate and fire disturbance determined regional pattern of vegetation biodiversity. The results provide a useful premise to devise a satellite-based assessment tool for foraging resource availability and biological regime shift by grazing and climate change in future study.

  17. Role of a Comprehensive Toxicity Assessment and Monitoring Program in the Management and Ecological Recovery of a Wastewater Receiving Stream

    Science.gov (United States)

    Greeley, Mark S.; Kszos, Lynn A.; Morris, Gail W.; Smith, John G.; Stewart, Arthur J.

    2011-06-01

    National Pollution Discharge Elimination Permit (NPDES)-driven effluent toxicity tests using Ceriodaphnia dubia and fathead minnows were conducted for more than 20 years to assess and monitor the effects of wastewaters at the United States (U.S.) Department of Energy Y-12 National Security Complex (Y-12 Complex) in Oak Ridge, Tennessee. Toxicity testing was also conducted on water samples from East Fork Poplar Creek (EFPC), the wastewater receiving stream, as part of a comprehensive biological monitoring and assessment program. In this paper, we evaluate the roles of this long-term toxicity assessment and monitoring program in the management and ecological recovery of EFPC. Effluent toxicity testing, associated toxicant evaluation studies, and ambient toxicity monitoring were instrumental in identifying toxicant sources at the Y-12 Complex, guiding modifications to wastewater treatment procedures, and assessing the success of various pollution-abatement actions. The elimination of untreated wastewater discharges, the dechlorination of remaining wastewater streams, and the implementation of flow management at the stream headwaters were the primary actions associated with significant reductions in the toxicity of stream water in the upper reaches of EFPC from the late 1980s through mid 1990s. Through time, as regulatory requirements changed and water quality improved, emphasis shifted from comprehensive toxicity assessments to more focused toxicity monitoring efforts. Ambient toxicity testing with C. dubia and fathead minnows was supplemented with less-standardized but more sensitive alternative laboratory toxicity tests and in situ bioassays. The Y-12 Complex biological monitoring experience demonstrates the value of toxicity studies to the management of a wastewater receiving stream.

  18. Determination of zeta potential in Planctomycetes and its application in heavy metals toxicity assessment.

    Science.gov (United States)

    Lage, Olga Maria; Bondoso, Joana; Catita, José A M

    2012-10-01

    Zeta potential of Planctomycetes was evaluated under different environmental conditions and correlated to cell viability. Phylogenetically distinct strains of the Planctomycetes presented different negative zeta potential values. More negative values were associated with Rhodopirellula spp. and related to the great amount of fimbriae in these species. Milli-Q water was chosen as the best dispersion media to perform the measurements. Zeta potential increased with ionic strength and varied with pH. In the physiological range of pH 5.0-9, zeta potential remained low and Rhodopirellula sp. strain LF2 cells were viable. Out of this range, zeta potential increased significantly and viability decreased. The effect on zeta potential of arsenic, cadmium, chromium, copper, lead, nickel, and zinc was assessed in Rhodopirellula sp. strain LF2. Zeta potential increased with increasing toxicity of the heavy metals in a dose-response way. This result was confirmed by the results observed for Rhodopirellula baltica strain SH1 under copper toxicity. Lead was the most toxic metal and zinc was the least toxic as observed by zeta potential and viability. The results support a correlation between zeta potential and cell viability which seem to indicate the possibility to use it as a viability predictor for the effects of heavy metals toxicity. PMID:22576374

  19. Sensitivity of isolated eggs of pond snails: a new method for toxicity assays and risk assessment.

    Science.gov (United States)

    Liu, Tengteng; Koene, Joris M; Dong, Xiaoxiao; Fu, Rongshu

    2013-05-01

    The concentration of heavy metals in the environment is normally low. We here address whether using the development of isolated pond snail Radix auricularia eggs would provide a more sensitive endpoint and whether the gelatinous matrix of the egg mass surrounding the eggs indeed protects the snail embryos. In the present study, artificial removal of the gelatinous matrix of egg masses greatly increased the sensitivity of developing eggs to a heavy metal (cadmium). The sensitivity of isolated eggs to cadmium was determined using several convenient endpoints, including mortality, hatching rate, and heart rate, with an acute toxicity test and a subchronic test. In the acute toxicity test, a 96-h LC(50) value of 58.26 μg/L cadmium was determined. In the subchronic toxicity test, sublethal effects in terms of a significant reduction in hatching rate could be found in the 25-μg/L treatment, and a significant decrease of heart rate was observed in both treatments (5 and 25 μg/L). The high sensitivity of isolated eggs indicates that such tests can be efficient for toxicity assays and risk assessment, although one needs to keep in mind that the ecologically relevant measure of toxicity will be how eggs are affected when they are still inside the egg mass.

  20. Microalgal motility measurement microfluidic chip for toxicity assessment of heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Guoxia [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Department of Biotechnology, Dalian, Liaoning (China); Dalian University, Dalian, Liaoning (China); Wang, Yunhua [Dalian University, Dalian, Liaoning (China); Qin, Jianhua [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Department of Biotechnology, Dalian, Liaoning (China)

    2012-12-15

    A polydimethylsiloxane microfluidic chip has been developed for the estimation of toxic heavy metals based on measurement of mobility of marine microalgae. The chip is mainly composed of an upstream concentration gradient generator and a downstream perfusion-based chemotatic module. The processes of toxic liquid dilution and diffusion, microalgal culturing, cell stimulation, and online screening can be integrated in this chip, which makes it an attractive approach to simplify toxicity testing procedures. The microalgal motility was adopted as a microfluidic bioassay signal and was evaluated as the percentage of motile cells, curvilinear velocity, average path velocity, and straight line velocity. Two mobile marine microalgae, Platymonas subcordiformis and Platymonas helgolandica var. tsingtaoensis, were confined in the chemotatic module and stimulated by the eight concentration gradients of Cu and Cd generated by the concentration gradient generator. In all cases, a toxic response was detected (i.e., a dose-related inhibition of motility was observed). Only 1.5 h was needed to predict EC{sub 50} values. Thus, the microfluidic chip developed was proved to be useful as a simple and rapid approach in heavy metal detection and might be expanded as a conventional test method in environmental toxicity assessment. (orig.)

  1. Assessments of Drought Impacts on Vegetation in China with the Optimal Time Scales of the Climatic Drought Index

    Directory of Open Access Journals (Sweden)

    Zheng Li

    2015-07-01

    Full Text Available Drought is expected to increase in frequency and severity due to global warming, and its impacts on vegetation are typically extensively evaluated with climatic drought indices, such as multi-scalar Standardized Precipitation Evapotranspiration Index (SPEI. We analyzed the covariation between the SPEIs of various time scales and the anomalies of the normalized difference vegetation index (NDVI, from which the vegetation type-related optimal time scales were retrieved. The results indicated that the optimal time scales of needle-leaved forest, broadleaf forest and shrubland were between 10 and 12 months, which were considerably longer than the grassland, meadow and cultivated vegetation ones (2 to 4 months. When the optimal vegetation type-related time scales were used, the SPEI could better reflect the vegetation’s responses to water conditions, with the correlation coefficients between SPEIs and NDVI anomalies increased by 5.88% to 28.4%. We investigated the spatio-temporal characteristics of drought and quantified the different responses of vegetation growth to drought during the growing season (April–October. The results revealed that the frequency of drought has increased in the 21st century with the drying trend occurring in most of China. These results are useful for ecological assessments and adapting management steps to mitigate the impact of drought on vegetation. They are helpful to employ water resources more efficiently and reduce potential damage to human health caused by water shortages.

  2. Assessing future vegetation trends and restoration prospects in the Karst regions of Southwest China

    DEFF Research Database (Denmark)

    Tong, Xiaowei; Wang, Kelin; Brandt, Martin;

    2016-01-01

    To alleviate the severe rocky desertification and improve the ecological conditions in Southwest China, the national and local Chinese governments have implemented a series of Ecological Restoration Projects since the late 1990s. In this context, remote sensing can be a valuable tool for conserva......To alleviate the severe rocky desertification and improve the ecological conditions in Southwest China, the national and local Chinese governments have implemented a series of Ecological Restoration Projects since the late 1990s. In this context, remote sensing can be a valuable tool...... are utilized. The proposed framework of this analysis has been proven to work well for assessing restoration prospects in the study area, and due to the generic design, the method is expected to be applicable for other areas of complex landscapes in the world to explore future trends of vegetation....

  3. Personal care product preservatives: risk assessment and mixture toxicities with an industrial wastewater.

    Science.gov (United States)

    Carbajo, Jose B; Perdigón-Melón, Jose A; Petre, Alice L; Rosal, Roberto; Letón, Pedro; García-Calvo, Eloy

    2015-04-01

    The aquatic toxicity of eight preservatives frequently used in personal care products (PCPs) (iodopropynyl butylcarbamate, bronopol, diazolidinyl urea, benzalkonium chloride, zinc pyrithione, propylparaben, triclosan and a mixture of methylchloroisothiazolinone and methylisothiazolinone) was assessed by means of two different approaches: a battery of bioassays composed of single species tests of bacteria (Vibrio fischeri and Pseudomonas putida) and protozoa (Tetrahymena thermophila), and a whole biological community resazurin-based assay using activated sludge. The tested preservatives showed considerable toxicity in the studied bioassays, but with a marked difference in potency. In fact, all biocides except propylparaben and diazolidinyl urea had EC50 values lower than 1 mg L(-1) in at least one assay. Risk quotients for zinc pyrithione, benzalkonium chloride, iodopropynyl butylcarbamate and triclosan as well as the mixture of the studied preservatives exceeded 1, indicating a potential risk for the process performance and efficiency of municipal sewage treatment plants (STPs). These four single biocides explained more than 95% of the preservative mixture risk in all bioassays. Each individual preservative was also tested in combination with an industrial wastewater (IWW) from a cosmetics manufacturing facility. The toxicity assessment was performed on binary mixtures (preservative + IWW) and carried out using the median-effect principle, which is a special case of the concept of Concentration Addition (CA). Almost 70% of all experiments resulted in EC50 values within a factor of 2 of the values predicted by the median-effect principle (CI values between 0.5 and 2). The rest of the mixtures whose toxicity was mispredicted by CA were assessed with the alternative concept of Independent Action (IA), which showed higher predictive power for the biological community assay. Therefore, the concept used to accurately predict the toxicity of mixtures of a preservative

  4. Accuracy Assessment Points for Effigy Mounds National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The U.S. Geological Survey Upper Midwest Environmental Sciences Center (UMESC) has produced a vegetation spatial database coverage (vegetation map) for the Effigy...

  5. Field Plot and Accuracy Assessment Points for Grand Portage National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The vegetation point data for Grand Portage National Monument (GRPO) was developed to support two projects associated with the 2006 vegetation map, the collection...

  6. Field Plot and Accuracy Assessment Points for Pictured Rocks National Lakeshore Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The vegetation point data for Pictured Rocks National Lakeshore (PIRO) was developed to support two projects associated with the 2004 vegetation map, the collection...

  7. Assessment of spatially distributed values of Kc using vegetation indices derived from medium resolution satellite data

    Science.gov (United States)

    Greco, M.; Simoniello, T.; Lanfredi, M.; Russo, A. L.

    2010-09-01

    In the last years, the theme of suitable assessment of irrigation water supply has been raised relevant interest for both general principles of sustainable development and optimization of water resources techniques and management. About 99% of the water used in agriculture is lost by crops as evapotranspiration (ET). Thus, it becomes crucial to drive direct or indirect measurement in order to perform a suitable evaluation of water loss by evapotranspiration (i.e. actual evapotranspiration) as well as crop water status and its effect on the production. The main methods used to measure evapotranspiration are available only at field scale (Bowen ratio, eddy correlation system, soil water balance) confined to a small pilot area, generally due to expense and logistical constraints. This led over the last 50 years to the development of a large number of empirical methods to estimate evapotranspiration through different climatic and meteorological variables as well as combining models, based on aerodynamic theory and energy balance, taking into account both canopy properties and meteorological conditions. Among these, the Penman-Monteith equation seems to give the best results providing a robust and consistent method world wide accepted. Such conventional methods only provide accurate evapotranspiration assessment for a homogeneous region nearby the meteorological gauge station and cannot be extrapolated to other different sites; whereas remote sensing techniques allow for filling up such a gap. Some of these satellite techniques are based on the use of thermal band signals as inputs for energy balance equations. Another common approach is mainly based on the FAO method for estimating crop evapotranspiration, in which evapotranspiration data are multiplied by crop coefficients, Kc, derived from satellite multispectral vegetation indices obtained. The rationale behind such a link considers that Kc and vegetation indices are sensitive to both leaf area index and fractional

  8. Assessing time-integrated dissolved concentrations and predicting toxicity of metals during diel cycling in streams

    Science.gov (United States)

    Balistrieri, Laurie S.; Nimick, David A.; Mebane, Christopher A.

    2012-01-01

    Evaluating water quality and the health of aquatic organisms is challenging in systems with systematic diel (24 h) or less predictable runoff-induced changes in water composition. To advance our understanding of how to evaluate environmental health in these dynamic systems, field studies of diel cycling were conducted in two streams (Silver Bow Creek and High Ore Creek) affected by historical mining activities in southwestern Montana. A combination of sampling and modeling tools was used to assess the toxicity of metals in these systems. Diffusive Gradients in Thin Films (DGT) samplers were deployed at multiple time intervals during diel sampling to confirm that DGT integrates time-varying concentrations of dissolved metals. Site specific water compositions, including time-integrated dissolved metal concentrations determined from DGT, a competitive, multiple-toxicant biotic ligand model, and the Windemere Humic Aqueous Model Version 6.0 (WHAM VI) were used to determine the equilibrium speciation of dissolved metals and biotic ligands. The model results were combined with previously collected toxicity data on cutthroat trout to derive a relationship that predicts the relative survivability of these fish at a given site. This integrative approach may prove useful for assessing water quality and toxicity of metals to aquatic organisms in dynamic systems and evaluating whether potential changes in environmental health of aquatic systems are due to anthropogenic activities or natural variability.

  9. Natural environment assessment and vegetation indicators for IWRM scenarios in the Upper Brahmaputra River Basin

    Science.gov (United States)

    Wagner, I.; Exler, N.; Janauer, G. A.

    2009-04-01

    The Brahmaputra River originates in the highest mountain massif of the world, the Western Himalaya. Fed by ice-melt, snow and also monsoon rain from the northern slope of the Himalaya Range in its reach in Tibet develops into a braided river with many channels in a wide valley, where it receives important tributaries like the Lhasa River, before entering the constrained reach of the Great Brahmaputra Gorge. Downstream of the Gorge the river enters even more diverse landscapes in intensively cultivated Assam, where the braided river bed reaches its greatest lateral expansion. Monsoon related flooding causes the most severe effects in this densely populated reach on the south-eastern rim of the Himalaya Range, but intense flooding is also a great threat at upper parts of the river and in populated areas of some tributaries. IWRM plays an important role with regard to mitigating climate change effects, whether too much or too little water is available for human uses. The assessment of the natural environment in a multi-scale approach leads to the identification of essential indicators, which are the basis for modelling scenarios of future development as the spatio-temporal processes vary within scale and along the course of this Large River. In our assessment it was necessary to aggregate local vegetation structures for a generalised description at larger scales to bridge the gap between the hydrological modelling scale and respective ecosystem services resulting from the existing vegetation types. These indicators can be used to evaluate the influence of different ecosystem types on related IWRM activities and policies. Aside from more general wetland ecosystem services like flood retention of support of livelihood for the neighbouring population a focus was also set on wetland and water body ecotones where detectable by high-resolution RS techniques to evaluate vulnerability and biodiversity aspects.

  10. Using a Household Food Inventory to Assess the Availability of Traditional Vegetables among Resettled African Refugees

    OpenAIRE

    Catherine Gichunge; Shawn Somerset; Neil Harris

    2016-01-01

    A cross-sectional sequential explanatory mixed methods study was conducted among household food preparers to examine the association between home availability and consumption of traditional vegetables among resettled African refugees living in Queensland, Australia. Home availability of traditional African vegetables was associated with age, having a vegetable garden, employment status, and having a supermarket in the local neighborhood. Food preparers from homes with low vegetable availabili...

  11. [Preliminary study on occurrence and health risk assessment of quinolone antibiotics in vegetables from Guangzhou, China].

    Science.gov (United States)

    Li, Yan-Wen; Zhang, Yan; Mo, Ce-Hui; Tai, Yi-Ping; Wu, Xiao-Lian; Wang, Ji-Yang; Su, Qing-Yun

    2010-10-01

    Quinolone antibiotics (QNs) including norfloxacin (NOR), enrofolxacin (ENR), ciprofloxacin (CIP) and lomefloxacin (LOM) in vegetable samples collected from Guangzhou were determined by high performance liquid chromatography (HPLC) coupled with fluorescent detector (FLD). The detected frequency of QNs was 96% in vegetables. The total concentration of quinolones (sigma QNs) detected in vegetable ranged from 1.0 microg/kg to 1 683.1 microg/kg (F.W.). Leafy vegetable topped the content of quinolones among the three types of vegetables, followed by the melon-fruit vegetable and rhizome vegetable. The detected frequency of the four quinolone antibiotics ranked as NOR > CIP > LOM > ENR. Except ENR, concentrations of CIP, NOR, LOM and sigma QNs in pollution-free vegetable, green vegetable and organic vegetable were higher than those in routine cultivated vegetables. The maximum contribution to ADI value (caculated by the sum of CIP and ENR) is estimated up to 41.5% and 83% for adults and children respectively via consumption of vegetables.

  12. A human pluripotent stem cell platform for assessing developmental neural toxicity screening

    OpenAIRE

    Hou, Zhonggang; Zhang, Jue; Schwartz, Michael P.; Stewart, Ron; Page, C David; Murphy, William L.; Thomson, James A

    2013-01-01

    A lack of affordable and effective testing and screening procedures mean surprisingly little is known about the health hazards of many of the tens of thousands of chemicals in use in the world today. The recent rise in the number of children affected by neurological disorders such as autism has stirred valuable debate about the role chemicals play in our daily life, highlighting the need for improved methods of assessing chemicals for developmental neural toxicity. Current methods of testing ...

  13. Toxicity Assessment of Buprofezin, Lufenuron, and Triflumuron to the Earthworm Aporrectodea caliginosa

    OpenAIRE

    Badawy, Mohamed E. I.; Anter Kenawy; Ahmed F. El-Aswad

    2013-01-01

    Earthworms are particularly important soil macroinvertebrates and are often used in assessing the general impact of pesticide pollution in soil. The present study was conducted in order to investigate the toxicity of three insect growth regulators (IGRs) buprofezin, lufenuron, and triflumuron, at different application rates and exposure times toward mature earthworms Aporrectodea caliginosa. The effects of these pesticides on the growth rate in relation to the activities of acetylcholinestera...

  14. Assessing the risks of trace elements in environmental materials under selected greenhouse vegetable production systems of China.

    Science.gov (United States)

    Chen, Yong; Huang, Biao; Hu, Wenyou; Weindorf, David C; Liu, Xiaoxiao; Niedermann, Silvana

    2014-02-01

    The risk assessment of trace elements of different environmental media in conventional and organic greenhouse vegetable production systems (CGVPS and OGVPS) can reveal the influence of different farming philosophy on the trace element accumulations and their effects on human health. These provide important basic data for the environmental protection and human health. This paper presents trace element accumulation characteristics of different land uses; reveals the difference of soil trace element accumulation both with and without consideration of background levels; compares the trace element uptake by main vegetables; and assesses the trace element risks of soils, vegetables, waters and agricultural inputs, using two selected greenhouse vegetable systems in Nanjing, China as examples. Results showed that greenhouse vegetable fields contained significant accumulations of Zn in CGVPS relative to rice-wheat rotation fields, open vegetable fields, and geochemical background levels, and this was the case for organic matter in OGVPS. The comparative analysis of the soil medium in two systems with consideration of geochemical background levels and evaluation of the geo-accumulation pollution index achieved a more reasonable comparison and accurate assessment relative to the direct comparison analysis and the evaluation of the Nemerow pollution index, respectively. According to the Chinese food safety standards and the value of the target hazard quotient or hazard index, trace element contents of vegetables were safe for local residents in both systems. However, the spatial distribution of the estimated hazard index for producers still presented certain specific hotspots which may cause potential risk for human health in CGVPS. The water was mainly influenced by nitrogen, especially for CGVPS, while the potential risk of Cd and Cu pollution came from sediments in OGVPS. The main inputs for trace elements were fertilizers which were relatively safe based on relevant

  15. Toxicity assessment for petroleum-contaminated soil using terrestrial invertebrates and plant bioassays.

    Science.gov (United States)

    Hentati, Olfa; Lachhab, Radhia; Ayadi, Mariem; Ksibi, Mohamed

    2013-04-01

    The assessment of soil quality after a chemical or oil spill and/or remediation effort may be measured by evaluating the toxicity of soil organisms. To enhance our understanding of the soil quality resulting from laboratory and oil field spill remediation, we assessed toxicity levels by using earthworms and springtails testing and plant growth experiments. Total petroleum hydrocarbons (TPH)-contaminated soil samples were collected from an oilfield in Sfax, Tunisia. Two types of bioassays were performed. The first assessed the toxicity of spiked crude oil (API gravity 32) in Organization for Economic Co-operation and Development artificial soil. The second evaluated the habitat function through the avoidance responses of earthworms and springtails and the ability of Avena sativa to grow in TPH-contaminated soils diluted with farmland soil. The EC50 of petroleum-contaminated soil for earthworms was 644 mg of TPH/kg of soil at 14 days, with 67 % of the earthworms dying after 14 days when the TPH content reached 1,000 mg/kg. The average germination rate, calculated 8 days after sowing, varied between 64 and 74 % in low contaminated soils and less than 50 % in highly contaminated soils. PMID:22773148

  16. Using a Household Food Inventory to Assess the Availability of Traditional Vegetables among Resettled African Refugees.

    Science.gov (United States)

    Gichunge, Catherine; Somerset, Shawn; Harris, Neil

    2016-01-18

    A cross-sectional sequential explanatory mixed methods study was conducted among household food preparers to examine the association between home availability and consumption of traditional vegetables among resettled African refugees living in Queensland, Australia. Home availability of traditional African vegetables was associated with age, having a vegetable garden, employment status, and having a supermarket in the local neighborhood. Food preparers from homes with low vegetable availability were less likely to consume the recommended number of vegetable servings. Barriers faced in the food environment included language, lack of availability of traditional vegetables and lack of transport. All of these aspects contributed to the study findings that both individual and food environment characteristics may play a role in access to and availability of food and vegetable consumption of resettled refugees. Consumption of traditional foods among the resettled refugees continues post resettlement.

  17. Using a Household Food Inventory to Assess the Availability of Traditional Vegetables among Resettled African Refugees.

    Science.gov (United States)

    Gichunge, Catherine; Somerset, Shawn; Harris, Neil

    2016-01-01

    A cross-sectional sequential explanatory mixed methods study was conducted among household food preparers to examine the association between home availability and consumption of traditional vegetables among resettled African refugees living in Queensland, Australia. Home availability of traditional African vegetables was associated with age, having a vegetable garden, employment status, and having a supermarket in the local neighborhood. Food preparers from homes with low vegetable availability were less likely to consume the recommended number of vegetable servings. Barriers faced in the food environment included language, lack of availability of traditional vegetables and lack of transport. All of these aspects contributed to the study findings that both individual and food environment characteristics may play a role in access to and availability of food and vegetable consumption of resettled refugees. Consumption of traditional foods among the resettled refugees continues post resettlement. PMID:26797623

  18. Decontamination of aquatic vegetable leaves by removing trace toxic metals during pickling process with acetic acid solution.

    Science.gov (United States)

    Wu, Wenbiao; Yang, Yixing

    2011-01-01

    The heavy-metal content of aquatic plants is mainly dependent upon their ecological system. This study indicated that although the toxic heavy-metal contents could be above the recommended maximum levels depending upon their concentrations in growing water, they can be decontaminated by pickling with 5% acetic acid solution. Almost all Cd, Hg, Ba, or Sb and 99.5% Pb, 96.7% Ag, or 97.1% Al were removed from Water Spinach leaves by soaking in acetic acid solution. For Water-Shield leaves, almost all Cd, Hg, Pb, Ba, or Sb and 95.0% Ag or 96.1% Al were removed. For Watercress leaves, almost all Cd, Hg, Ba, or Sb and 99.0% Pb or 99.7% Ag were removed. For Water Hyacinth leaves, almost all Cd, Ba, or Sb and 99.0% Hg, 98.5% Pb, 95.0% Ag, or 98.7% Al were removed. PMID:21888602

  19. Metabolic and Dynamic Profiling for Risk Assessment of Fluopyram, a Typical Phenylamide Fungicide Widely Applied in Vegetable Ecosystem

    Science.gov (United States)

    Wei, Peng; Liu, Yanan; Li, Wenzhuo; Qian, Yuan; Nie, Yanxia; Kim, Dongyeop; Wang, Mengcen

    2016-09-01

    Fluopyram, a typical phenylamide fungicide, was widely applied to protect fruit vegetables from fungal pathogens-responsible yield loss. Highly linked to the ecological and dietary risks, its residual and metabolic profiles in the fruit vegetable ecosystem still remained obscure. Here, an approach using modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction combined with GC-MS/MS analysis was developed to investigate fluopyram fate in the typical fruit vegetables including tomato, cucumber, pepper under the greenhouse environment. Fluopyram dissipated in accordance with the first-order rate dynamics equation with the maximum half-life of 5.7 d. Cleveage of fluopyram into 2-trifluoromethyl benzamide and subsequent formation of 3-chloro-5-(trifluoromethyl) pyridine-2-acetic acid and 3-chloro-5-(trifluoromethyl) picolinic acid was elucidated to be its ubiquitous metabolic pathway. Moreover, the incurrence of fluopyram at the pre-harvest interval (PHI) of 7–21 d was between 0.0108 and 0.1603 mg/kg, and the Hazard Quotients (HQs) were calculated to be less than 1, indicating temporary safety on consumption of the fruit vegetables incurred with fluopyram, irrespective of the uncertain toxicity of the metabolites. Taken together, our findings reveal the residual essential of fluopyram in the typical agricultural ecosystem, and would advance the further insight into ecological risk posed by this fungicide associated with its metabolites.

  20. Assessing Geomorphic and Vegetative Responses to Environmental Flows in the Willamette River Basin

    Science.gov (United States)

    Mangano, J.; Jones, K.; Wallick, R.; Bach, L.; Olson, M.; Bervid, H.

    2015-12-01

    On regulated rivers, restoring flow regimes is a process-based restoration approach that may strongly affect downstream ecosystems. Developing realistic flow targets with meaningful geomorphic and ecological benefits, however, is challenging. For instance, hydraulic, geomorphic and biological processes are affected by more than manipulating water release—sediment supply and transport conditions also require consideration. Also, funding and programmatic directives rarely require the monitoring necessary to adaptively manage environmental flow programs. Recent research in the Willamette River basin in support of the Sustainable Rivers Project (SRP) demonstrates how such a monitoring program can be implemented. At the reach scale, initial efforts have assessed geomorphic and vegetative changes in alluvial sections of the Middle Fork Willamette and McKenzie Rivers using repeat mapping from aerial photographs and flow analyses. Overall, both rivers are largely stable because of reduced discharge, bed-material supply and local revetments, but some reaches of the McKenzie River are more dynamic, perhaps reflecting greater inputs of sediment from unregulated tributaries and higher magnitude peak flows. Repeat, reach-scale mapping on the Middle Fork Willamette River shows that frequent bankfull flows are able to scour minimally vegetated gravel bars and sustain a patchwork of actively shifting bed-material sediment. Repeat mapping on the McKenzie River in summer 2015 will reveal insights about the geomorphic effectiveness of bankfull flows. At the site scale, monitoring at two bars in summer 2015 is linking streamflow with the establishment of black cottonwood. Lastly, a review of hydrographs from 2000-2015 and retrospectively applying stakeholder-defined flow targets showed substantial variability in meeting objectives for the timing and types of flows under traditional regulated conditions and the SRP. Altogether, these related efforts help link streamflow, geomorphic

  1. Assessment of fire behavior and management options in subalpine vegetation on Mauna Kea, Hawai'i

    Science.gov (United States)

    Thaxton, Jarrod M.; Jacobi, James D.

    2009-01-01

    Fire is a major threat to habitat for the endangered Palila (Loxioides bailleui) within subalpine vegetation on Mauna Kea volcano, Hawai‘i. The presence of large amounts of fine fuel from grasses, dry climate, and human ignition sources produces a significant risk of wildfire in this area year-round. The purpose of this report is to provide information on fuels and potential fire behavior that will contribute to fire management of Palila habitat. Recommended actions will contribute to the conservation of these native forests and facilitate restoration in degraded areas. To assess the effects of grass invasion on fuel conditions and potential fire danger, we quantified vegetation and fuels across an elevation gradient from grasslands into sub-alpine forests on the west slope of Mauna Kea. Our results indicated that grass cover was reduced under tree canopy in plots below ~2,500 m elevation, but at higher elevations grass cover was higher under trees than in the open. However, tree canopy cover below 2,500 m elevation was not high enough overall (~25% on average) to result in significant reductions in fine fuels at the landscape level. Sampling directly under and away from tree crowns at multiple elevations suggested that below ~2,500 m, the presence of tree canopy cover can reduce grass fuels significantly. Furthermore, moisture content of live surface fuels was increased under tree canopy compared with open areas. These results suggest that restoration of forest cover may have the potential to alter grass fuels in ways that decrease the threat of fire in some subalpine forests. Fire behavior estimates based on fuel data from grasslands, mixed forest and māmane forest indicated the need for fuelbreaks of at least 20-30 m to limit fire spread in most areas. In many cases, breaks as wide as 40 m are required to limit fire spread risk under extreme weather conditions.

  2. Assessment of toxic effects of triclosan on the terrestrial snail (Achatina fulica).

    Science.gov (United States)

    Wang, Xiaonan; Liu, Zhengtao; Wang, Wanhua; Yan, Zhenguang; Zhang, Cong; Wang, Weili; Chen, Lihong

    2014-08-01

    Triclosan (TCS) is a broad-spectrum antimicrobial agent used in personal care products, and as a result, is widespread in the environment. Toxicity tests of TCS on aquatic organisms have been reported, but limited toxicity data on terrestrial species are available. In this study, the 28-d chronic toxicity of TCS on the biomass, shell diameter growth, and total food intake of the terrestrial snail Achatina fulica were tested. Moreover, biochemical responses, including changes in the activity of catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), and the content of malondialdehyde (MDA), were examined after 14-d and 28-d exposure. Results showed that TCS had toxic effects on the biomass, shell diameter growth, and total food intake of A. fulica with no observed effect concentration (NOEC) values of 24 mg kg(-1). As for the antioxidant enzymes, TCS caused significant oxidative stress even at the low concentration of 24 mg kg(-1). The CAT and POD activities at the high concentrations of 200 and 340 mg kg(-1), respectively, were significantly inhibited. The SOD and CAT activity in treatments below 118 mg kg(-1) and the MDA content in all treatments showed dose-effect relationships. This study demonstrated that TCS caused adverse effects on terrestrial invertebrates, and provided valuable information for the risk assessment imposed by TCS in the terrestrial environment.

  3. Assessment of heavy metals bioavailability and toxicity toward Vibrio fischeri in sediment of the Huelva estuary.

    Science.gov (United States)

    Rosado, Daniel; Usero, José; Morillo, José

    2016-06-01

    Relationship between toxicity and bioavailable metals in sediments from the Huelva estuary and its littoral of influence was analyzed. Toxicity was assessed with Microtox(®) bioassay using a marine luminescent bacterium: Vibrio fischeri. Bioavailable metals were considered as both, acid extractable fraction of BCR procedure and the sum of exchangeable and bound to carbonates fractions of Tessier sequential extraction. A bioavailable metals index was calculated to integrate results in a single figure. Toxicity and bioavailable metals showed a similar pattern. Higher levels were found in the estuary than in the littoral (140 TU/g). In Huelva estuary, highest levels were found in the Tinto estuary (5725 TU/g), followed by the Odiel estuary (5100 TU/g) and the Padre Santo Canal (2500 TU/g). Results in this area were well over than those in nearby estuaries. Furthermore, they are similar to or even higher than those in other polluted sediments around the world. Bioavailable metal index showed a stronger correlation with acid extractable fraction of BCR (R(2) = 0.704) than that for the sum of exchangeable and bound to carbonates fractions of Tessier (R(2) = 0.661). These results suggest that bioavailable metals are an important source of sediment toxicity in the Huelva estuary and its littoral of influence, an area with one of the highest mortality risks of Spain. PMID:27002282

  4. Toxicological assessment of kretek cigarettes Part 4: mechanistic investigations, smoke chemistry and in vitro toxicity.

    Science.gov (United States)

    Roemer, E; Dempsey, R; Lawless-Pyne, J; Lukman, S; Evans, A Deger; Trelles-Sticken, E; Wittke, S; Schorp, M K

    2014-12-01

    The smoke chemistry and in vitro toxicity of mainstream smoke (MS) was investigated in American-blended cigarettes with or without the addition of 2.5%, 5% or 10% eugenol to the tobacco and in Indonesian-blended cigarettes with and without the addition of cloves, cloves extracted with hot ethanol, and extracted cloves replenished with eugenol or clove oil. The addition of eugenol reduced the concentration of nearly all toxicants measured in MS as well as the in vitro cytotoxicity of the gas/vapor phase. Reductions were also seen in bacterial mutagenicity of the total particulate matter (TPM) assessed by the Ames Assay. The addition of extracted cloves led to increases and decreases of toxicant concentrations in MS. Replenishment with eugenol or clove oil decreased the toxicant concentrations; with most smoke constituent concentrations reduced below the concentration found in tobacco-only cigarettes. Cytotoxicity of the TPM was not affected by the clove preparations. However, GVP cytotoxicity was reduced (untreated cloves showing the highest reductions). Mutagenicity of TPM was decreased by the clove preparations. Mechanisms for the reductions, (up to 40%), are most likely due to dilution effects by eugenol, changed burning characteristics of the tobacco, and free radical scavenging by eugenol. PMID:25455230

  5. Assessment of sub-chronic, hematological and histopathological toxicities of a herbal combination.

    Science.gov (United States)

    Ahmed, Shadab; Khan, Rafeeq Alam; Feroz, Zeeshan

    2015-11-01

    The herbal combination under study consists of Withania somnifera, Tribulus terrestris, Mucuna pruriens and Argyria speciosa. Present study is mainly designed to investigate the gross physical, sub-chronic, hematological and histopathological effects of the combination widely used for its stimulating, revitalizing and fertility boosting effects in Pakistan. Sub-chronic, hematological and histopathological outcomes of herbal combination were assessed on 27 albino rabbits weighing from 1000 gm-1500 gm after giving herbal combination for 60 days in two doses 27 and 81 mg/kg against control. No significant toxicity was revealed during the entire period of study, however some biochemical changes were observed in kidney and liver but these changes did not coincide with histopathological findings. There was no mortality and evidence of systemic toxicity including hematological toxicity following 60 days administration of herbal combination. Results of present study suggest that further studies are required on large number of animals before reaching to a definite conclusion, more over clinical studies should also be conducted to confirm the possible toxic effects of the herbal combination. PMID:26639483

  6. 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

  7. Assessment of Vegetation Variation on Primarily Creation Zones of the Dust Storms Around the Euphrates Using Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Jamil Amanollahi

    2012-06-01

    Full Text Available Recently, period frequency and effect domain of the dust storms that enter Iran from Iraq have increased. In this study, in addition to detecting the creation zones of the dust storms, the effect of vegetation cover variation on their creation was investigated using remote sensing. Moderate resolution image Spectroradiometer (MODIS and Landsat Thematic Mapper (TM5 have been utilized to identify the primarily creation zones of the dust storms and to assess the vegetation cover variation, respectively. Vegetation cover variation was studied using Normalized Differences Vegetation Index (NDVI obtained from band 3 and band 4 of the Landsate satellite. The results showed that the surrounding area of the Euphrates in Syria, the desert in the vicinity of this river in Iraq, including the deserts of Alanbar Province, and the north deserts of Saudi Arabia are the primarily creation zones of the dust storms entering west and south west of Iran. The results of NDVI showed that excluding the deserts in the border of Syria and Iraq, the area with very weak vegetation cover have increased between 2.44% and 20.65% from 1991 to 2009. In the meanwhile, the retention pound surface areas in the south deserts of Syria as well as the deserts in its border with Iraq have decreased 6320 and 4397 hectares, respectively. As it can be concluded from the findings, one of the main environmental parameters initiating these dust storms is the decrease in the vegetation cover in their primarily creation zones.

  8. Landscape level assessment of critically endangered vegetation of Lakshadweep islands using geo-spatial techniques

    Indian Academy of Sciences (India)

    C Sudhakar Reddy; Bijan Debnath; P Hari Krishna; C S Jha

    2013-04-01

    The conservation of biodiversity is essential for human survival and quality of the environment. Lakshadweep islands are vulnerable to global change and the representing remnant natural vegetation. Landscape fragmentation, disturbance regimes and biological richness have been studied using geo-spatial techniques. Littoral vegetation is the only natural vegetation type of Lakshadweep islands. Altogether 59 patches of the littoral vegetation occupying an area of 137.2 ha were identified. 58.06% of the littoral vegetation patches belongs to the patch-size class of > 5 ha. The remnant natural vegetation surviving with patches of less than 20 ha size indicates severe anthropogenic pressure. The fragmentation of littoral vegetation habitat into smaller isolated patches poses one of the key threats to biodiversity and coastal environment. Phytosociological observations revealed distinct plant communities and presence of invasive species in littoral vegetation. The high disturbance areas accounted for 59.11% area of the total vegetation. The overall spatial distribution of biological richness (BR) in Lakshadweep shows maximum BR at low level (78%), followed by medium (19%), high (2%) and very high (1%). The study emphasizes the importance of conserving the remnant natural vegetation, which is critically endangered.

  9. Comparative study of non-invasive methods for assessing Daphnia magna embryo toxicity.

    Science.gov (United States)

    Stensberg, Matthew C; Zeitchek, Michael Anthony; Inn, Kul; McLamore, Eric S; Porterfield, D Marshall; Sepúlveda, Maria S

    2014-09-01

    Embryos, unlike adults, are typically sessile, which allows for an increase in the available metrics that can be used to assess chemical toxicity. We investigate Daphnia magna development rate and oxygen consumption as toxicity metrics and compare them to arrested embryo development using four different techniques with potassium cyanide (KCN) as a common toxicant. The EC50 (95 % CI) for arrested development was 2,535 (1,747-3,677) μg/L KCN. Using pixel intensity changes, recorded with difference imaging, we semi-quantitatively assessed a decrease in development rate at 200 μg/L KCN, threefold lower than the arrested development lowest observed effect concentration (LOEC). Respirometry and self-referencing (SR) microsensors were two unique techniques used to assess oxygen consumption. Using respirometry, an increase in oxygen consumption was found in the 5 μg/L KCN treatment and a decrease for 148 μg/L, but no change was found for the 78 μg/L KCN treatment. Whereas, with SR microsensors, we were able to detect significant changes in oxygen consumption for all three treatments: 5, 78, and 148 μg/L KCN. While SR offered the highest sensitivity, the respirometry platform developed for this study was much easier to use to measure the same endpoint. Oxygen consumption may be subject to change during the development process, meaning consumption assessment techniques may only be useful only for short-term experiments. Development rate was a more sensitive endpoint though was only reliable four of the six embryonic developmental stages examined. Despite being the least sensitive endpoint, arrested embryo development was the only technique capable of assessing the embryos throughout all developmental stages. In conclusion, each metric has advantages and limitations, but because all are non-invasive, it is possible to use any combination of the three. PMID:24888613

  10. Toxicokinetics/toxicodynamics links bioavailability for assessing arsenic uptake and toxicity in three aquaculture species.

    Science.gov (United States)

    Chen, Wei-Yu; Liao, Chung-Min

    2012-11-01

    The purpose of this study was to link toxicokinetics/toxicodynamics (TK/TD) and bioavailability-based metal uptake kinetics to assess arsenic (As) uptake and bioaccumulation in three common farmed species of tilapia (Oreochromis mossambicus), milkfish (Chanos chanos), and freshwater clam (Corbicula fluminea). We developed a mechanistic framework by linking damage assessment model (DAM) and bioavailability-based Michaelis-Menten model for describing TK/TD and As uptake mechanisms. The proposed model was verified with published acute toxicity data. The estimated TK/TD parameters were used to simulate the relationship between bioavailable As uptake and susceptibility probability. The As toxicity was also evaluated based on a constructed elimination-recovery scheme. Absorption rate constants were estimated to be 0.025, 0.016, and 0.175 mL g(-1) h(-1) and As uptake rate constant estimates were 22.875, 63.125, and 788.318 ng g(-1) h(-1) for tilapia, milkfish, and freshwater clam, respectively. Here we showed that a potential trade-off between capacities of As elimination and damage recovery was found among three farmed species. Moreover, the susceptibility probability can also be estimated by the elimination-recovery relations. This study suggested that bioavailability-based uptake kinetics and TK/TD-based DAM could be integrated for assessing metal uptake and toxicity in aquatic organisms. This study is useful to quantitatively assess the complex environmental behavior of metal uptake and implicate to risk assessment of metals in aquaculture systems.

  11. Risk assessment of toxic heavy metals in the abandoned metal mine areas, Korea

    Science.gov (United States)

    Lee, J. S.; Chon, H. T.

    2003-04-01

    The purpose of this study is to assess the risk of adverse health effects on human exposure to toxic heavy metals influenced by past mining activities. Environmental geochemical survey was undertaken in the abandoned metal mine areas (Dongil Au-Ag-Cu-Zn mine, Okdong Cu-Pb-Zn mine, Myungbong Au-Ag mine). After appropriate sample preparation, tailings, soils, crop plants and groundwaters were analyzed for As, Cd, Cu, Pb and Zn by ICP-AES and ICP-MS. Health risk assessment of toxic heavy metals has been performed with chemical analytical data for environmental media. Arsenic and other heavy metals are highly elevated in the tailings from the Dongil mine (8,720 As mg/kg, 5.9 Cd mg/kg, 3,610 Cu mg/kg, 5,850 Pb mg/kg, 630 Zn mg/kg), but heavy metals except As from the Okdong mine (72 As mg/kg, 53.6 Cd mg/kg, 910 Cu mg/kg, 1,590 Pb mg/kg, 5,720 Zn mg/kg) and only As from the Myungbong mine (5,810 As mg/kg). These significant concentrations can impact on soils and waters around the tailing files. Also, elevated levels of As, Cd, Cu, Pb and Zn are found in agricultural soils from these mine areas. Risk assessment modeling is subdivided into main four stages, i.e. hazard identification, exposure assessment, toxicity (dose-response) assessment and risk characterization. In order to assess exposure it is necessary to calculate the average daily dose (ADD) of contaminant via the three identified pathways (soil, groundwater and food (rice grain) pathways). In dose-response assessment for non-carcinogens, reference doses (RfD) are calculated and that for carcinogens, slope factors (SF) are obtained by US-EPA IRIS database. In risk characterization, the results of toxicity assessment and exposure assessment are integrated to arrive at quantitative estimates of cancer risks and hazard quotients. Toxic (non-cancer) risks are indicated in terms of a hazard quotient (H.Q.) and this risk exists for H.Q.>1. The H.Q. values for only As from the Dongil and Myungbong mine areas are 2.1 and

  12. Whole effluent toxicity testing -- Usefulness, level of protection, and risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, P.M.

    2000-01-01

    The general status of whole effluent toxicity (WET) tests is assessed relative to their generally accepted purpose of identifying, characterizing, and eliminating effects of effluents on aquatic resources. Although WET tests are useful, they are not perfect tools. Imperfections include the innate variability of these tests, due both to biotic and anthropogenic factors; the reality of species differences both between the laboratory and the field and within the field; and differences between the laboratory and the receiving environment. Whole effluent toxicity tests may be overprotective, underprotective, or offer an uncertain level of protection. The implication of hormesis and inverted U-shaped dose responses for WET testing are reviewed in particular detail. Comparisons to field conditions indicate that WET tests are not reliable predictors of effects or lack of effects in the receiving environment. Whole effluent toxicity tests are only the first stage in a risk assessment and as such identify hazard, not risk. Identification of risk requires discarding the concept of independent applicability. The appropriate use of WET tests is identified in the context of their advantages and disadvantages.

  13. Assessment of the toxicity of cyclohexanone administered intravenously to Wistar and Gunn rats.

    Science.gov (United States)

    Greener, Y; Martis, L; Indacochea-Redmond, N

    1982-09-01

    The toxicity of cyclohexanone, used as a solvent cement in polyvinyl chloride medical devices, was assessed in Wistar and Gunn rats. The Gunn rat was used because it has a negligible activity of UDP glucuronosyltransferase toward bilirubin and certain other aglycones. Cyclohexanone was administered iv for 28 consecutive days to Wistar and Gunn rats in two doses (50 and 100 mg/kg), using solutions containing 0.25 and 0.50 g per 100 ml, respectively, at a constant volume of 20 mg/kg. Saline (0.9% NaCl) was used as the control. Daily observations for signs of toxicity showed no adverse effects in Wistar or Gunn rats injected with either dose. Daily weight changes of control and test animals were similar. Ophthalmologic examinations revealed no treatment-related structural lesions. No adverse effects were noted when the data from the hemogram or clinical chemistry parameters were evaluated. Gross pathological and histopathologic assessment showed no alterations due to cyclohexanone treatment. Urinary excretions of total and glucuronide conjugates of cyclohexanol were similar for Wistar and Gunn rats; less than 1% was excreted as free cyclohexanone and cyclohexanol. It is concluded that the Gunn rat is capable of forming glucuronides of cyclohexanol and that cyclohexanone at these doses has a negligible toxic potential.

  14. Modified whole effluent toxicity test to assess and decouple wastewater effects from environmental gradients.

    Directory of Open Access Journals (Sweden)

    Sebastián Sauco

    Full Text Available Environmental gradients and wastewater discharges produce aggregated effects on marine populations, obscuring the detection of human impact. Classical assessment methods do not include environmental effects in toxicity tests designs, which could lead to incorrect conclusions. We proposed a modified Whole Effluent Toxicity test (mWET that includes environmental gradients in addition to effluent dilutions, together with the application of Generalized Linear Mixed Models (GLMM to assess and decouple those effects. We tested this approach, analyzing the lethal effects of wastewater on a marine sandy beach bivalve affected by an artificial canal freshwater discharge used for rice crops irrigation. To this end, we compared bivalve mortality between canal water dilutions (CWd and salinity controls (SC: without canal water. CWd were prepared by diluting the water effluent (sampled during the pesticide application period with artificial marine water. The salinity gradient was included in the design by achieving the same final salinities in both CWd and SC, allowing us to account for the effects of salinity by including this variable as a random factor in the GLMM. Our approach detected significantly higher mortalities in CWd, indicating potential toxic effects of the effluent discharge. mWET represents an improvement over the internationally standardized WET tests, since it considers environmental variability and uses appropriate statistical analyses.

  15. Google Street View as an alternative method to car surveys in large-scale vegetation assessments.

    Science.gov (United States)

    Deus, Ernesto; Silva, Joaquim S; Catry, Filipe X; Rocha, Miguel; Moreira, Francisco

    2015-10-01

    Car surveys (CS) are a common method for assessing the distribution of alien invasive plants. Google Street View (GSV), a free-access web technology where users may experience a virtual travel along roads, has been suggested as a cost-effective alternative to car surveys. We tested if we could replicate the results from a countrywide survey conducted by car in Portugal using GSV as a remote sensing tool, aiming at assessing the distribution of Eucalyptus globulus Labill. wildlings on roadsides adjacent to eucalypt stands. Georeferenced points gathered along CS were used to create road transects visible as lines overlapping the road in GSV environment, allowing surveying the same sampling areas using both methods. This paper presents the results of the comparison between the two methods. Both methods produced similar models of plant abundance, selecting the same explanatory variables, in the same hierarchical order of importance and depicting a similar influence on plant abundance. Even though the GSV model had a lower performance and the GSV survey detected fewer plants, additional variables collected exclusively with GSV improved model performance and provided a new insight into additional factors influencing plant abundance. The survey using GSV required ca. 9 % of the funds and 62 % of the time needed to accomplish the CS. We conclude that GSV may be a cost-effective alternative to CS. We discuss some advantages and limitations of GSV as a survey method. We forecast that GSV may become a widespread tool in road ecology, particularly in large-scale vegetation assessments. PMID:27624742

  16. Diagnostic accuracy of the vegetative and minimally conscious state: Clinical consensus versus standardized neurobehavioral assessment

    Directory of Open Access Journals (Sweden)

    Majerus Steve

    2009-07-01

    Full Text Available Abstract Background Previously published studies have reported that up to 43% of patients with disorders of consciousness are erroneously assigned a diagnosis of vegetative state (VS. However, no recent studies have investigated the accuracy of this grave clinical diagnosis. In this study, we compared consensus-based diagnoses of VS and MCS to those based on a well-established standardized neurobehavioral rating scale, the JFK Coma Recovery Scale-Revised (CRS-R. Methods We prospectively followed 103 patients (55 ± 19 years with mixed etiologies and compared the clinical consensus diagnosis provided by the physician on the basis of the medical staff's daily observations to diagnoses derived from CRS-R assessments performed by research staff. All patients were assigned a diagnosis of 'VS', 'MCS' or 'uncertain diagnosis.' Results Of the 44 patients diagnosed with VS based on the clinical consensus of the medical team, 18 (41% were found to be in MCS following standardized assessment with the CRS-R. In the 41 patients with a consensus diagnosis of MCS, 4 (10% had emerged from MCS, according to the CRS-R. We also found that the majority of patients assigned an uncertain diagnosis by clinical consensus (89% were in MCS based on CRS-R findings. Conclusion Despite the importance of diagnostic accuracy, the rate of misdiagnosis of VS has not substantially changed in the past 15 years. Standardized neurobehavioral assessment is a more sensitive means of establishing differential diagnosis in patients with disorders of consciousness when compared to diagnoses determined by clinical consensus.

  17. Assessing water stress of desert vegetation using remote sensing : the case of the Tamarugo forest in the Atacama Desert (Northern Chile)

    OpenAIRE

    Chávez Oyanadel, R.O.

    2014-01-01

    Water stress assessment of natural vegetation plays a key role in water management of desert ecosystems. It allows scientists and managers to relate water extraction rates to changes in vegetation water condition, and consequently to define safe water extraction rates for maintaining a healthy ecosystem. Previous research has shown that optical remote sensing constitutes a powerful tool for assessing vegetation water stress due to its capability of quantitatively estimating important paramete...

  18. [Assessment of the in vitro and in vivo toxicity of 3,4-dihydroxyphenylacetaldehyde (DOPAL)].

    Science.gov (United States)

    Bonnet, J-J; Legros, H; Janin, Fr; Dourmap, N; Costentin, J

    2004-09-01

    This work was carried out in order to evaluate the in vitro and in vivo toxicity of 3,4-dihydroxyphenylacetaldehyde (DOPAL). This aldehyde is formed from dopamine (DA) by monoamine oxidases (MAO) and is mainly oxidised to 3,4-dihydroxyphenylacetic acid by brain aldehyde dehydrogenases (ALDH), or eventually reduced to 3,4-dihydroxyphenylethanol by aldose/aldehyde reductases. In vitro, catecholaminergic SH-SY5Y cells were incubated with DA and disulfiram (DSF), an irreversible inhibitor of ALDH. As evidenced by MTT assays, a 24-h treatment with 10(-4) M DA and/or 10(-6) M DSF followed by a 24-h incubation in a drug-free medium evidenced that the toxicity of each of these drugs was potentiated by the second drug. HPLC measurements demonstrated that this drug association induced an early DOPAL production that could result in a delayed cell toxicity. For in vivo studies, male Sprague-Dawley rats were treated with L-DOPA-benserazide, which increases the production of DOPAL by MAO, and DSF. An acute injection of DSF (100mg/kg i.p.) and L-DOPA/benserazide (100mg/kg+25mg/kg, 24h later) significantly increased the DOPAL striatal level. However, a 30-day treatment with DSF (100mg/kg i.p., once every two days) and L-DOPA/benserazide (100mg/kg+25mg/kg, twice a day) did not affect both indexes used to assess the integrity of the nigro-striatal dopaminergic terminals (i.e. the striatal content in DA and the binding to the vesicular monoamine transporter on striatal membranes). These results do not support the hypothesis of a DOPAL toxicity and argue against the toxicity of L-DOPA therapy.

  19. Correlation of the five test methods to assess chemical toxicity and relation to physical properties

    Energy Technology Data Exchange (ETDEWEB)

    Yoshioka, Y.; Ose, Y.; Sato, T.

    1986-08-01

    Biological tests using Orizias latipes (LC50 and oxygen uptake test), Moina macrocopa (LC50), and Dugesia japonica (head regeneration test and LC50) were carried out in order to clarify the mutual relationship of these test methods. The oxygen uptake rate of O. latipes was not effective to assess chemical toxicity. Adding the results of the growth inhibition test of Tetrahymena pyriformis (Yoshioka, Y., Ose, Y., and Sato, T. (1985). Sci. Total Environ. 43, 149-157), the correlation coefficients between each two test methods were calculated. The test results except EC50 and LC50 of D. japonica showed a good relation to each other. We determined the solubility and the n-octanol/water partition coefficient (P) of some chemicals used in the test. Log P interpreted the toxicity in mol/liter unit but not in mg/liter. Solubility was not a useful descripter neither in mol/liter nor in mg/liter unit.

  20. Biochemical parameters in Tubifex tubifex as an integral part of complex sediment toxicity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Smutna, M.; Hilscherova, K.; Paskova, V. [Masaryk Univ., Brno (CZ). RECETOX (Research Centre for Environmental Chemistry and Ecotoxicology); Marsalek, B [Czech Academy of Science, Brno (Czech Republic). Centre for Cyanobacteria and their Toxins

    2008-06-15

    Background, aim, and scope Restoration of lakes and reservoirs with extensive cyanobacterial water bloom often requires evaluation of the sediment quality. Next to the chemical analysis of known pollutants, sediment bioassays should be employed to assess toxicity of the present contaminants and to make predictions of associated risk. Brno reservoir in the Czech Republic is a typical example of water bodies with long-term problems concerning cyanobacterial water blooms. Comprehensive assessment of reservoir sediment quality was conducted since successful reservoir restoration might require sediment removal. An important part of this survey focused on an examination of the utility of Tubifex tubifex and its sublethal biochemical markers for the assessment of direct sediment toxicity. Materials and methods This complex study included chemical analysis of contaminants (heavy metals, organic pollutants), ecotoxicity testing of sediment elutriates (tests with Daphnia magna, Pseudomonas putida, Sinapis alba, Scenedesmus subspicatus), and other parameters. We have tested in more detail the applicability of T. tubifex as a test organism for direct evaluation of contact sediment toxicity. Survival tests after 14 days of exposure were complemented by an assessment of parameters serving as biomarkers for sublethal effects [such as total glutathione content (GSH), activities of the enzymes glutathione transferase (GST), glutathione peroxidase (GPx), and glutathione reductase (GR)]. The data matrix was subjected to multivariate analysis to interpret relationships between different parameters and possible differences among locations. Results The multivariate statistical techniques helped to clearly identify the more contaminated upstream sites and separate them from the less contaminated and reference samples. The data document closer relationships of the detected sediment contamination with results of direct sediment exposure in the T. tubifex test regarding mortality but namely

  1. Toxicity Assessment of the Xanthid Crab Demania cultripes from Cebu Island, Philippines

    Directory of Open Access Journals (Sweden)

    Manabu Asakawa

    2010-01-01

    Full Text Available Several cases of poisoning resulting in human fatalities and stemming from the ingestion of coral reef crabs have been reported from the Indo-Pacific region. We assessed the toxicity of the unidentified xanthid crab collected from the Camotes Sea off the eastern coast of Cebu Island, central Visayas region of Philippines from the food hygienic point of view. All seven specimens, which were identified with Demania cultripes, collected in 2006 were toxic to mice irrespective of the season of collection and induced paralytic symptoms typical of tetrodotoxin (TTX and paralytic shellfish poison (PSP. The activity was expressed in mouse unit (MU being defined as the amount of TTX to kill a 20 g ddY male mice in 30 min after i.p. injection. Toxicity scores for viscera and appendages of specimens were 18.2±16.0 (mean ± S.D. and 4.4±2.6 MU/g, respectively. The highest individual toxicity scores observed for viscera and appendages were 52.1 and 7.7 MU/g, respectively. The frequency of toxic samples was 100%. Toxin profiles as determined by high-performance liquid chromatography-fluorescent detection analysis (HPLC-FLD revealed that TTX was the main toxic principle accounting for about 90% of the total toxicity along with 4-epi TTX and 4,9-anhydroTTX. Furthermore, gas chromatography-mass spectrometry (GC-MS analysis revealed mass fragment ion peaks at m/z 376, 392 and 407, which were characteristic of the quinazoline skeleton (C9-base specific to TTX. In addition, only a small amount of PSP containing gonyautoxins1–4 and hydroxysaxitoxin was detected. To our knowledge, this is the first report presenting evidence of occurrence of TTX and PSP in the xanthid crab D. cultripes inhabiting waters surrounding Cebu Island. From food hygienic point of view, people in coastal areas should be warned of the potential hazard of this crab in order to prevent its intentional or accidental consumption.

  2. Toxicity assessment due to sub-chronic exposure to individual and mixtures of four toxic heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Cobbina, Samuel J.; Chen, Yao [School of the Environment, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013, Jiangsu (China); Zhou, Zhaoxiang; Wu, Xueshan; Zhao, Ting [School of Chemistry and Chemical Engineering, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013 (China); Zhang, Zhen [School of the Environment, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013, Jiangsu (China); Feng, Weiwei; Wang, Wei [School of Food and Biological Engineering, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013, Jiangsu (China); Li, Qian [School of Pharmacy, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013, Jiangsu (China); Wu, Xiangyang, E-mail: wuxy@ujs.edu.cn [School of the Environment, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013, Jiangsu (China); Yang, Liuqing, E-mail: yangliuqing@ujs.edu.cn [School of Chemistry and Chemical Engineering, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013 (China)

    2015-08-30

    Highlights: • Low dose single and mixtures of toxic metals had adverse effect on mice. • Metal mixtures exhibited higher toxicities compared to individual metals. • Mixtures of low dose Pb + Hg + Cd induced neuronal degeneration in brain of mice. • Exposure to Pb + Hg + As + Cd showed renal tubular necrosis in kidney. - Abstract: Humans are exposed to a cocktail of heavy metal toxicants in the environment. Though heavy metals are deleterious, there is a paucity of information on toxicity of low dose mixtures. In this study, lead (Pb) (0.01 mg/L), mercury (Hg) (0.001 mg/L), cadmium (Cd) (0.005 mg/L) and arsenic (As) (0.01 mg/L) were administered individually and as mixtures to 10 groups of 40 three-week old mice (20 males and 20 females), for 120 days. The study established that low dose exposures induced toxicity to the brain, liver, and kidney of mice. Metal mixtures showed higher toxicities compared to individual metals, as exposure to low dose Pb + Hg + Cd reduced brain weight and induced structural lesions, such as neuronal degeneration in 30-days. Pb + Hg + Cd and Pb + Hg + As + Cd exposure induced hepatocellular injury to mice evidenced by decreased antioxidant activities with marginal increases in MDA. These were accentuated by increases in ALT, AST and ALP. Interactions in metal mixtures were basically synergistic in nature and exposure to Pb + Hg + As + Cd induced renal tubular necrosis in kidneys of mice. This study underlines the importance of elucidating the toxicity of low dose metal mixtures so as to protect public health.

  3. Health risk assessment of heavy metals in vegetables grown around battery production area

    Directory of Open Access Journals (Sweden)

    Ying Chen

    2014-04-01

    Full Text Available Battery production is one of the main sources of heavy metals that present great harm to human health even in low concentrations. Chromium (Cr, Cadmium (Cd and Lead (Pb were measured in edible portions of vegetables and soils around a battery production area in China, and the potential health risk of heavy metal contamination to the local population via vegetable consumption was evaluated. Their concentrations in edible portions of vegetables were 2.354 (0.078-14.878, 0.035 (0.003-0.230 and 0.039 (0.003-0.178 mg kg-1, respectively. Approximately 3 % of the Cd in the vegetable samples exceeded the maximum concentration allowable by national food safety criteria, although Pb content in all samples were within the criteria. Transfer factors (TF from soils to vegetables were dependent on vegetable species. Leguminous vegetables were more likely to accumulate Cr, while leaf vegetables tended to show higher levels of concentration of Cd and Pb. Melon vegetables demonstrated a relatively low capacity for accumulating the heavy metals studied. TF were positively correlated with soil organic matter and negatively correlated with soil pH. The mean estimated daily intake of Cr, Cd and Pb via dietary consumption of vegetables was 0.011, 1.65 × 10-4 and 1.84 × 10-4 mg kg-1 of body weight per day, respectively, levels that were much lower than the reference doses recommended by USEPA (U.S. Environmental Protection Agency and JECFA (Joint FAO/WHO Expert Committee on Food Additives, indicating that the potential health risk of Cr, Cd and Pb exposure via vegetable consumption to the local population around this battery production area could be negligible.

  4. Using the Implicit Association Test and the Implicit Relational Assessment Procedure to Measure Attitudes toward Meat and Vegetables in Vegetarians and Meat-Eaters

    Science.gov (United States)

    Barnes-Holmes, Dermot; Murtagh, Louise; Barnes-Holmes, Yvonne; Stewart, Ian

    2010-01-01

    The current study aimed to assess the implicit attitudes of vegetarians and non-vegetarians towards meat and vegetables, using the Implicit Association Test (IAT) and the Implicit Relational Assessment Procedure (IRAP). Both measures involved asking participants to respond, under time pressure, to pictures of meat or vegetables as either positive…

  5. Development of a multi-component Damage Assessment Model (MDAM) for time-dependent mixture toxicity with toxicokinetic interactions.

    Science.gov (United States)

    Lee, Jong-Hyeon; Landrum, Peter F

    2006-02-15

    A new mixture toxicity model was developed to predict the time-dependent toxicity of a mixture with toxicokinetic interactions directed specifically toward addressing biotransformation. The Damage Assessment Model (DAM), a toxicokinetic-toxicodynamic model that describes and predicts the time-dependent toxicity of a single compound, was extended to a multicomponent model for mixture toxicity. The model assumes that cumulative damage from the parent compound, metabolites, and/or a biotransformation inhibitor are additive, and the sum of the cumulative damage determines mixture toxicity. Since incorporation of the damage addition hypothesis into the DAM was equivalent to an independent action model for mixture toxicity, it was applied to describe the combined effect of mixture components with potentially dissimilar modes of action. From the multicomponent DAM, a time-dependent toxic unit model was derived and applied to determine the toxic units of mixture components. This model suggests a series of experimental designs required to assess the role of biotransformation in the toxicity of metabolized organic compounds and a data analysis method to separately estimate toxicodynamic parameters forthe parent compound and metabolites. PMID:16572795

  6. An integrated approach to improved toxicity prediction for the safety assessment during preclinical drug development using Hep G2 cells

    International Nuclear Information System (INIS)

    Efficient and accurate safety assessment of compounds is extremely important in the preclinical development of drugs especially when hepatotoxicty is in question. Multiparameter and time resolved assays are expected to greatly improve the prediction of toxicity by assessing complex mechanisms of toxicity. An integrated approach is presented in which Hep G2 cells and primary rat hepatocytes are compared in frequently used cytotoxicity assays for parent compound toxicity. The interassay variability was determined. The cytotoxicity assays were also compared with a reliable alternative time resolved respirometric assay. The set of training compounds consisted of well known hepatotoxins; amiodarone, carbamazepine, clozapine, diclofenac, tacrine, troglitazone and verapamil. The sensitivity of both cell systems in each tested assay was determined. Results show that careful selection of assay parameters and inclusion of a kinetic time resolved assay improves prediction for non-metabolism mediated toxicity using Hep G2 cells as indicated by a sensitivity ratio of 1. The drugs with EC50 values 100 μM or lower were considered toxic. The difference in the sensitivity of the two cell systems to carbamazepine which causes toxicity via reactive metabolites emphasizes the importance of human cell based in-vitro assays. Using the described system, primary rat hepatocytes do not offer advantage over the Hep G2 cells in parent compound toxicity evaluation. Moreover, respiration method is non invasive, highly sensitive and allows following the time course of toxicity. Respiration assay could serve as early indicator of changes that subsequently lead to toxicity.

  7. Assessment of the toxicity of wastewater from the metalworking industry treated using a conventional physico-chemical process.

    Science.gov (United States)

    Machado, Rodrigo Matuella; Monteggia, Luiz Olinto; Arenzon, Alexandre; Curia, Ana Cristina

    2016-06-01

    This article presents results from a toxicity reduction evaluation program intended to describe wastewater from the metalworking industry that was treated using a conventional physico-chemical process. The toxicity of the wastewater for the microcrustacean Daphnia magna was predominantly expressive. Alkaline cyanide wastewater generated from electroplating accounted for the largest number of samples with expressive toxicity. When the raw wastewater concentrations in the batches were repeated, inexpressive toxicity variations were observed more frequently among the coagulated-flocculated samples. At the coagulation-flocculation step, 22.2 % of the treatments had reduced acute toxicity, 30.6 % showed increased toxicity, and 47.2 % remained unchanged. The conductivity and total dissolved solids contents of the wastewater indicated the presence of salts with charges that were inappropriate for the survival of daphnid. The wastewaters treated by neutralization and coagulation-flocculation had average metallic compound contents that were greater than the reference toxic concentrations reported in other studies, suggesting that metals likely contributed to the toxic effects of the wastewater on freshwater microcrustaceans. Thus, alternative coagulants and flocculants should be assessed, and feasible doses should be determined to improve wastewater treatment. In addition, advanced treatment processes should be assessed for their abilities to remove dissolved toxic salts and ions. PMID:27230425

  8. Fruit and Vegetable Intake Assessed by Food Frequency Questionnaire and Plasma Carotenoids: A Validation Study in Adults

    Directory of Open Access Journals (Sweden)

    Tracy L. Burrows

    2015-05-01

    Full Text Available Dietary validation studies of self-reported fruit and vegetable intake should ideally include measurement of plasma biomarkers of intake. The aim was to conduct a validation study of self-reported fruit and vegetable intakes in adults, using the Australian Eating Survey (AES food frequency questionnaire (FFQ, against a range of plasma carotenoids. Dietary intakes were assessed using the semi-quantitative 120 item AES FFQ. Fasting plasma carotenoids (α- and β-carotene, lutein/zeaxanthin, lycopene and cryptoxanthin were assessed using high performance liquid chromatography in a sample of 38 adult volunteers (66% female. Significant positive correlations were found between FFQ and plasma carotenoids for α-carotene, β-carotene and lutein/zeaxanthin (52%, 47%, 26%, p < 0.001, 0.003, 0.041; respectively and relationships between plasma carotenoids (except lycopene and weight status metrics (BMI, waist circumference, fat mass were negative and highly significant. The results of the current study demonstrate that carotenoid intakes as assessed by the AES FFQ are significantly related to plasma concentrations of α-carotene, β-carotene and lutein/zeaxanthin, the carotenoids commonly found in fruit and vegetables. Lower levels of all plasma carotenoids, except lycopene, were found in individuals with higher BMI. We conclude that the AES can be used to measure fruit and vegetable intakes with confidence.

  9. Assessment of Iranian Agroclimatological Zone Classification by Using TVDI (Temperature Vegetation Dryness Index)

    Science.gov (United States)

    Asadi, Ebrahim; Lopez-Baeza, Ernesto; Coll Pajaron, M. Amparo; Kouzehgaran, Saeedeh; Haghighat, Masoud

    2016-07-01

    Agricultural zoning is an important tool for authorities to plan and decide about development of the agricultural sector, environmental sustainability issues and plan and provide irrigation and rural infrastructures. Previous different methods have suggested the definition of agroclimatological zones in big areas in Iran, but most of them are not easy to be validated or there are not clear criteria to evaluate whether the zones are correctly defined or not. The current {it Iranian Meteorological Organisation} classification is composed of six significant agroclimatological zones defined using the fundamental climate elements of temperature and precipitation obtained from 30 years data from 180 synoptic stations interpolated using regression kriging methods. Elevation was derived from SRTM (Shuttle Radar Topography Mission) digital elevation model of 90 m resolution. In this paper we assess the homogeneity of each of these conventionally defined agroclimatological zones using {bf TVDI (Temperature Vegetation Dryness Index)} values obtained from MODIS land surface temperature and NDVI operational products of the last three years between 2013 and 2015.

  10. Assessing and Mitigating the Effects of Windblown Soil on Rare and Common Vegetation

    Science.gov (United States)

    Gleason, Sean M.; Faucette, Dave T.; Toyofuku, Mai M.; Torres, Carlos A.; Bagley, Calvin F.

    2007-12-01

    Acting under the auspices of the US Endangered Species Act, we quantified wind erosion and its effects on rare and common plant species on a semi-arid military installation in Hawaii. Our goal was to develop management strategies, based on local data, to aid the conservation of rare and common indigenous plants and their habitats. We collected windblown soil coming off of roads and other disturbed soils to assess likely impacts to plants occurring at certain heights and distances from disturbed surfaces. We then subjected plants in a glasshouse to windblown dust treatments, designed from our field data to simulate erosion events, and evaluated the effect of these treatments on photosynthesis and survival. We also designed several field experiments to examine the in-situ effects of windblown soil and soil substrate on germination, growth rate, and survival of indigenous and nonindigenous plants. We conclude from these experiments that most direct effects of windblown soil to plants can be effectively mitigated by locating roads and training areas at least 40 m from sensitive plant habitats and through vegetation management to maintain at least 11% aerial cover on disturbed surfaces. Effects of soil type on germination, growth, and survival was species-specific, emphasizing the importance of species trials prior to, or during, rehabilitation efforts.

  11. Coastwide Reference Monitoring System (CRMS) Vegetation Volume Index: An assessment tool for marsh habitat focused on the three-dimensional structure at CRMS vegetation monitoring stations

    Science.gov (United States)

    Wood, William B.; Visser, Jenneke M.; Piazza, Sarai C.; Sharp, Leigh Anne; Hundy, Laura C.; McGinnis, Tommy E.

    2015-12-04

    A Vegetation Volume (VV) variable and Vegetation Volume Index (VVI) have been developed for the Coastwide Reference Monitoring System (CRMS). The VV is a measure of the amount of three-dimensional vegetative structure present at each CRMS site and is based on vegetation data collected annually. The VV uses 10 stations per CRMS site to quantify four vegetation layers: carpet, herbaceous, shrub, and tree. For each layer an overall live vegetation percent cover and height are collected to create a layer volume; the individual layer volumes are then summed to generate a site vegetation volume profile. The VV uses the two-dimensional area of live vegetative cover (in square meters) multiplied by the height (in meters) of each layer to produce a volume (in cubic meters) for each layer present in a 2-meter by 2-meter station. These layers are additive, yielding a total volume for each of the 10 herbaceous vegetation stations and an overall CRMS marsh site average.

  12. Assessing the Impacts of Low Carbohydrate Related Health Information on the Market Demand for US Vegetables

    OpenAIRE

    Paudel, Laxmi; Adhikari, Murali; Houston, Jack E.

    2005-01-01

    An Almost Ideal Demand System was estimated to examine the impacts of low carbohydrate information on the market demand for US vegetables. Analysis was extended to examine the performance of alternative carbohydrate information indexes. Study shows significant robust impacts of low carbohydrate information across all included vegetables. Results favor the general and weighted carbohydrate information index.

  13. Drought footprint on European ecosystems between 1999 and 2010 assessed by remotely sensed vegetation phenology and productivity

    DEFF Research Database (Denmark)

    Ivits, Eva; Horion, Stéphanie Marie Anne F; Fensholt, Rasmus;

    2014-01-01

    bioclimatic zones. The Standardized Precipitation and Evapotranspiration Index (SPEI) was used as drought indicator whereas changes in growing season length and vegetation productivity were assessed using remote sensing time-series of Normalized Difference Vegetation Index (NDVI). Drought spatio......Drought affects more people than any other natural disaster but there is little understanding of how ecosystems react to droughts. This study jointly analyzed spatio-temporal changes of drought patterns with vegetation phenology and productivity changes between 1999 and 2010 in major European......-temporal variability was analyzed using a Principal Component Analysis, leading to the identification of four major drought events between 1999 and 2010 in Europe. Correspondence Analysis showed that at the continental scale the productivity and phenology reacted differently to the identified drought events depending...

  14. A Case Study on a Trial Site in Western Austria to Assess Benefits of Railway Lineside Vegetation

    Science.gov (United States)

    Hoerbinger, Stephan; Obriejetan, Michael

    2016-04-01

    Lineside vegetation along railways can provide a wide range of ecosystem services and benefits. At the same time, there are several specific demands on the vegetation systems ensuring maintenance of highest standards of safety and operational performance. As a first step of the study, these demands on lineside vegetation but also their potentials for both rail specific internal and external benefits were summarized. For further analyses a case study was performed. A trial site, located in Austriás western federal state of Vorarlberg, was selected. The overall trial corridor was 22 km long and offered a large diversity in geomorphology, embankment types and surrounding land cover. A GIS-based classification of location types was conducted by using available open source geodata. Additionally, images, taken every fifty meters by a camera, mounted on a locomotive, supported the classification process. Following parameter were assessed: type of the track body, geomorphology, site conditions, technical facilities and surrounding land cover. Along railway infrastructure facilities, ecosystem services, provided by the lineside vegetation, are closely associated with improvement of the stability and resilience of embankments and cuttings. At the same time, specific criteria that must be fulfilled at every location type. These are safety and technical issues, such as keeping the railway clearance profile, economical issues respectively avoiding additional maintenance costs by strong plant growth. Supplementary ecosystem services are strongly related to the position in the landscape and the surrounding land cover. Along urban structures, that can be noise- or sight protection, provided by the lineside vegetation. On location types along agricultural land, lineside vegetation can provide ecological corridors or enhance the landscape structure. In this context, ecosystem services were derived to the previously assigned location types. The result of the case study is a GIS

  15. An assessment of soybeans and other vegetable proteins as source of salmonella contamination in pig production

    Directory of Open Access Journals (Sweden)

    Häggblom Per

    2010-02-01

    Full Text Available Abstract Background The impact of salmonella contaminated feed ingredients on the risk for spreading salmonella to pigs was assessed in response to two incidences when salmonella was spread by feed from two feed mills to 78 swine producing herds. Methods The assessment was based on results from the salmonella surveillance of feed ingredients before introduction to feed mills and from HACCP - based surveillance of the feed mills. Results from the mills of the Company (A that produced the salmonella contaminated feed, were by the Chi. Square test compared to the results from all the other (B - E feed producers registered in Sweden. Isolated serovars were compared to serovars from human cases of salmonellosis. Results Salmonella (28 serovars was frequently isolated from imported consignments of soybean meal (14.6% and rape seed meal (10.0%. Company A largely imported soybean meal from crushing plants with a history of unknown or frequent salmonella contamination. The risk for consignments of vegetable proteins to be salmonella contaminated was 2.4 times (P Conclusions Salmonella contaminated feed ingredients are an important source for introducing salmonella into the feed and food chain. Effective HACCP-based control and associated corrective actions are required to prevent salmonella contamination of feed. Efforts should be taken to prevent salmonella contamination already at the crushing plants. This is challenge for the EU - feed industry due to the fact that 98% of the use of soybean/meal, an essential feed ingredient, is imported from crushing plants of third countries usually with an unknown salmonella status.

  16. Assessing the risks of trace elements in environmental materials under selected greenhouse vegetable production systems of China

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yong [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Huang, Biao, E-mail: bhuang@issas.ac.cn [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Hu, Wenyou [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Weindorf, David C.; Liu, Xiaoxiao [Department of Plant and Soil Science, Texas Tech University, Lubbock, TX (United States); Niedermann, Silvana [Department of Environmental Systems Science, Institute of Agricultural Science, ETH Zurich, 8092 Zurich (Switzerland)

    2014-02-01

    The risk assessment of trace elements of different environmental media in conventional and organic greenhouse vegetable production systems (CGVPS and OGVPS) can reveal the influence of different farming philosophy on the trace element accumulations and their effects on human health. These provide important basic data for the environmental protection and human health. This paper presents trace element accumulation characteristics of different land uses; reveals the difference of soil trace element accumulation both with and without consideration of background levels; compares the trace element uptake by main vegetables; and assesses the trace element risks of soils, vegetables, waters and agricultural inputs, using two selected greenhouse vegetable systems in Nanjing, China as examples. Results showed that greenhouse vegetable fields contained significant accumulations of Zn in CGVPS relative to rice–wheat rotation fields, open vegetable fields, and geochemical background levels, and this was the case for organic matter in OGVPS. The comparative analysis of the soil medium in two systems with consideration of geochemical background levels and evaluation of the geo-accumulation pollution index achieved a more reasonable comparison and accurate assessment relative to the direct comparison analysis and the evaluation of the Nemerow pollution index, respectively. According to the Chinese food safety standards and the value of the target hazard quotient or hazard index, trace element contents of vegetables were safe for local residents in both systems. However, the spatial distribution of the estimated hazard index for producers still presented certain specific hotspots which may cause potential risk for human health in CGVPS. The water was mainly influenced by nitrogen, especially for CGVPS, while the potential risk of Cd and Cu pollution came from sediments in OGVPS. The main inputs for trace elements were fertilizers which were relatively safe based on relevant

  17. Assessing the risks of trace elements in environmental materials under selected greenhouse vegetable production systems of China

    International Nuclear Information System (INIS)

    The risk assessment of trace elements of different environmental media in conventional and organic greenhouse vegetable production systems (CGVPS and OGVPS) can reveal the influence of different farming philosophy on the trace element accumulations and their effects on human health. These provide important basic data for the environmental protection and human health. This paper presents trace element accumulation characteristics of different land uses; reveals the difference of soil trace element accumulation both with and without consideration of background levels; compares the trace element uptake by main vegetables; and assesses the trace element risks of soils, vegetables, waters and agricultural inputs, using two selected greenhouse vegetable systems in Nanjing, China as examples. Results showed that greenhouse vegetable fields contained significant accumulations of Zn in CGVPS relative to rice–wheat rotation fields, open vegetable fields, and geochemical background levels, and this was the case for organic matter in OGVPS. The comparative analysis of the soil medium in two systems with consideration of geochemical background levels and evaluation of the geo-accumulation pollution index achieved a more reasonable comparison and accurate assessment relative to the direct comparison analysis and the evaluation of the Nemerow pollution index, respectively. According to the Chinese food safety standards and the value of the target hazard quotient or hazard index, trace element contents of vegetables were safe for local residents in both systems. However, the spatial distribution of the estimated hazard index for producers still presented certain specific hotspots which may cause potential risk for human health in CGVPS. The water was mainly influenced by nitrogen, especially for CGVPS, while the potential risk of Cd and Cu pollution came from sediments in OGVPS. The main inputs for trace elements were fertilizers which were relatively safe based on relevant

  18. Employing UAVs to Acquire Detailed Vegetation and Bare Ground Data for Assessing Rangeland Health

    Science.gov (United States)

    Rango, A.; Laliberte, A.; Herrick, J. E.; Winters, C.

    2007-12-01

    Because of its value as a historical record (extending back to the mid 1930s), aerial photography is an important tool used in many rangeland studies. However, these historical photos are not very useful for detailed analysis of rangeland health because of inadequate spatial resolution and scheduling limitations. These issues are now being resolved by using Unmanned Aerial Vehicles (UAVs) over rangeland study areas. Spatial resolution improvements have been rapid in the last 10 years from the QuickBird satellite through improved aerial photography to the new UAV coverage and have utilized improved sensors and the more simplistic approach of low altitude flights. Our rangeland health experiments have shown that the low altitude UAV digital photography is preferred by rangeland scientists because it allows, for the first time, their identification of vegetation and land surface patterns and patches, gap sizes, bare soil percentages, and vegetation type. This hyperspatial imagery (imagery with a resolution finer than the object of interest) is obtained at about 5cm resolution by flying at an altitude of 150m above the surface of the Jornada Experimental Range in southern New Mexico. Additionally, the UAV provides improved temporal flexibility, such as flights immediately following fires, floods, and other catastrophic disturbances, because the flight capability is located near the study area and the vehicles are under the direct control of the users, eliminating the additional steps associated with budgets and contracts. There are significant challenges to improve the data to make them useful for operational agencies, namely, image distortion with inexpensive, consumer grade digital cameras, difficulty in detecting sufficient ground control points in small scenes (152m by 114m), accuracy of exterior UAV information on X,Y, Z, roll, pitch, and heading, the sheer number of images collected, and developing reliable relationships with ground-based data across a broad

  19. Drought footprint on European ecosystems between 1999 and 2010 assessed by remotely sensed vegetation phenology and productivity.

    Science.gov (United States)

    Ivits, Eva; Horion, Stephanie; Fensholt, Rasmus; Cherlet, Michael

    2014-02-01

    Drought affects more people than any other natural disaster but there is little understanding of how ecosystems react to droughts. This study jointly analyzed spatio-temporal changes of drought patterns with vegetation phenology and productivity changes between 1999 and 2010 in major European bioclimatic zones. The Standardized Precipitation and Evapotranspiration Index (SPEI) was used as drought indicator whereas changes in growing season length and vegetation productivity were assessed using remote sensing time-series of Normalized Difference Vegetation Index (NDVI). Drought spatio-temporal variability was analyzed using a Principal Component Analysis, leading to the identification of four major drought events between 1999 and 2010 in Europe. Correspondence Analysis showed that at the continental scale the productivity and phenology reacted differently to the identified drought events depending on ecosystem and land cover. Northern and Mediterranean ecosystems proved to be more resilient to droughts in terms of vegetation phenology and productivity developments. Western Atlantic regions and Eastern Europe showed strong agglomerations of decreased productivity and shorter vegetation growing season length, indicating that these ecosystems did not buffer the effects of drought well. In a climate change perspective, increase in drought frequency or intensity may result in larger impacts over these ecosystems, thus management and adaptation strategies should be strengthened in these areas of concerns.

  20. Bioaccumulation of Antimony and Arsenic in Vegetables and Health Risk Assessment in the Superlarge Antimony-Mining Area, China

    Directory of Open Access Journals (Sweden)

    Defang Zeng

    2015-01-01

    Full Text Available Heavy metal pollution in soils caused by mining and smelting has attracted worldwide attention for its potential health risks to residents. This paper studies the concentrations and accumulations of Sb and As in both soils and vegetables and the human health risks of Sb and As in vegetables from Xikuangshan (XKS Sb mine, Hunan, China. Results showed that the soils were severely polluted by Sb and As; Sb and As have significant positive correlation. Sb and As concentrations in vegetables were quite different: Coriandrum sativum L. was the highest in Sb, Allium fistulosum L. was the highest in As, and Brassica pekinensis L. was the lowest in both Sb and As; Daucus carota L. and Coriandrum sativum L. showed advantage in accumulating Sb and As; Coriandrum sativum L. had higher capacity of redistributing Sb and As within the plant. Health risk assessment results showed that the hazard quotient (HQ values of Sb and As in vegetables were in the ranges of 1.61–3.33 and 0.09–0.39, respectively; the chronic daily intake (CDI and hazard quotient (HQ values of Sb were over the safe limit recommended by FAO and WHO, indicating that long-term consumption of vegetables from the surrounding soils of XKS mine may bring health risks to residents.

  1. An assessment of health risks associated with arsenic exposure via consumption of homegrown vegetables near contaminated glassworks sites.

    Science.gov (United States)

    Uddh-Söderberg, Terese E; Gunnarsson, Sara J; Hogmalm, K Johan; Lindegård, M I Boel G; Augustsson, Anna L M

    2015-12-01

    The health risk posed by arsenic in vegetables grown in private gardens near 22 contaminated glassworks sites was investigated in this study. Firstly, vegetable (lettuce and potato) and soil samples were collected and arsenic concentrations measured to characterize the arsenic uptake in the selected crops. Secondly, a probabilistic exposure assessment was conducted to estimate the average daily intake (ADIveg), which was then evaluated against toxicological reference values by the calculation of hazard quotients (HQs) and cancer risks (CRs). The results show that elevated arsenic concentrations in residential garden soils are mirrored by elevated concentrations in vegetables, and that consumption of these vegetables alone may result in an unacceptable cancer risk; the calculated reasonable maximum exposure, for example, corresponded to a cancer incidence 20 times higher than the stated tolerance limit. However, the characterization of risk depends to a great extent on which toxicological reference value is used for comparison, as well as how the exposure is determined. Based on the assumptions made in the present study, the threshold levels for chronic non-carcinogenic or acute effects were not exceeded, but the cancer risks indicated highlight the need for further exposure studies, as dietary intake involves more than just homegrown vegetables and total exposure is a function of more than just one exposure pathway. In addition, glassworks sites--and contaminated sites in general--contain multiple contaminants, affecting the final and total risk.

  2. Metal uptake by homegrown vegetables – The relative importance in human health risk assessments at contaminated sites

    International Nuclear Information System (INIS)

    Risk assessments of contaminated land often involve the use of generic bioconcentration factors (BCFs), which express contaminant concentrations in edible plant parts as a function of the concentration in soil, in order to assess the risks associated with consumption of homegrown vegetables. This study aimed to quantify variability in BCFs and evaluate the implications of this variability for human exposure assessments, focusing on cadmium (Cd) and lead (Pb) in lettuce and potatoes sampled around 22 contaminated glassworks sites. In addition, risks associated with measured Cd and Pb concentrations in soil and vegetable samples were characterized and a probabilistic exposure assessment was conducted to estimate the likelihood of local residents exceeding tolerable daily intakes. The results show that concentrations in vegetables were only moderately elevated despite high concentrations in soil, and most samples complied with applicable foodstuff legislation. Still, the daily intake of Cd (but not Pb) was assessed to exceed toxicological thresholds for about a fifth of the study population. Bioconcentration factors were found to vary more than indicated by previous studies, but decreasing BCFs with increasing metal concentrations in the soil can explain why the calculated exposure is only moderately affected by the choice of BCF value when generic soil guideline values are exceeded and the risk may be unacceptable. - Highlights: • Uptake of Cd and Pb by lettuce and potatoes increased with soil contamination. • Consumption of homegrown vegetables may lead to a daily Cd intake above TDIs. • The variability in the calculated BCFs is high when compared to previous studies. • Exposure assessments are most sensitive to the choice of BCFs at low contamination

  3. Metal uptake by homegrown vegetables – The relative importance in human health risk assessments at contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    Augustsson, Anna L.M., E-mail: anna.augustsson@lnu.se [Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar (Sweden); Uddh-Söderberg, Terese E. [Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar (Sweden); Hogmalm, K. Johan [Department of Earth Sciences, University of Gothenburg, Gothenburg (Sweden); Filipsson, Monika E.M. [Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar (Sweden)

    2015-04-15

    Risk assessments of contaminated land often involve the use of generic bioconcentration factors (BCFs), which express contaminant concentrations in edible plant parts as a function of the concentration in soil, in order to assess the risks associated with consumption of homegrown vegetables. This study aimed to quantify variability in BCFs and evaluate the implications of this variability for human exposure assessments, focusing on cadmium (Cd) and lead (Pb) in lettuce and potatoes sampled around 22 contaminated glassworks sites. In addition, risks associated with measured Cd and Pb concentrations in soil and vegetable samples were characterized and a probabilistic exposure assessment was conducted to estimate the likelihood of local residents exceeding tolerable daily intakes. The results show that concentrations in vegetables were only moderately elevated despite high concentrations in soil, and most samples complied with applicable foodstuff legislation. Still, the daily intake of Cd (but not Pb) was assessed to exceed toxicological thresholds for about a fifth of the study population. Bioconcentration factors were found to vary more than indicated by previous studies, but decreasing BCFs with increasing metal concentrations in the soil can explain why the calculated exposure is only moderately affected by the choice of BCF value when generic soil guideline values are exceeded and the risk may be unacceptable. - Highlights: • Uptake of Cd and Pb by lettuce and potatoes increased with soil contamination. • Consumption of homegrown vegetables may lead to a daily Cd intake above TDIs. • The variability in the calculated BCFs is high when compared to previous studies. • Exposure assessments are most sensitive to the choice of BCFs at low contamination.

  4. The assessment of inflammatory activity and toxicity of treated sewage using RAW264.7 cells

    OpenAIRE

    Makene, Vedastus W.; Pool, Edmund J.

    2015-01-01

    Abstract Toxicity and inflammatory activity of wastewater samples were evaluated using RAW264.7 cells as a bioassay model. The RAW264.7 cell cultures were exposed to sterile filtered wastewater samples collected from a sewage treatment plant. Cell viability was evaluated using WST‐1 and XTT assays. Inflammatory effects of samples were assessed by determination of nitric oxide (NO) and interleukin 6 (IL‐6). The NO was estimated using the Griess reaction and IL‐6 was measured by enzyme‐linked i...

  5. Human health risk assessment of potentially toxic elements (PTEs) from environmental matrices

    OpenAIRE

    Elom, Nwabueze

    2012-01-01

    In assessing human health risk of potentially toxic elements (PTEs), it is not the concentration of PTEs in the environmental matrices that is of greatest concern but the fraction that is absorbed into the body via the exposure pathways. The determination of this fraction (i.e. the bioaccessible fraction) through the application of bioaccessibility protocols is the focus of this work. The study investigated human health risk of PTEs (As, Cd, Cr, Cu, Pb, Mn, Ni and Zn) from oral ingestion of s...

  6. Pharmacophore modeling and in silico toxicity assessment of potential anticancer agents from African medicinal plants.

    Science.gov (United States)

    Ntie-Kang, Fidele; Simoben, Conrad Veranso; Karaman, Berin; Ngwa, Valery Fuh; Judson, Philip Neville; Sippl, Wolfgang; Mbaze, Luc Meva'a

    2016-01-01

    Molecular modeling has been employed in the search for lead compounds of chemotherapy to fight cancer. In this study, pharmacophore models have been generated and validated for use in virtual screening protocols for eight known anticancer drug targets, including tyrosine kinase, protein kinase B β, cyclin-dependent kinase, protein farnesyltransferase, human protein kinase, glycogen synthase kinase, and indoleamine 2,3-dioxygenase 1. Pharmacophore models were validated through receiver operating characteristic and Güner-Henry scoring methods, indicating that several of the models generated could be useful for the identification of potential anticancer agents from natural product databases. The validated pharmacophore models were used as three-dimensional search queries for virtual screening of the newly developed AfroCancer database (~400 compounds from African medicinal plants), along with the Naturally Occurring Plant-based Anticancer Compound-Activity-Target dataset (comprising ~1,500 published naturally occurring plant-based compounds from around the world). Additionally, an in silico assessment of toxicity of the two datasets was carried out by the use of 88 toxicity end points predicted by the Lhasa's expert knowledge-based system (Derek), showing that only an insignificant proportion of the promising anticancer agents would be likely showing high toxicity profiles. A diversity study of the two datasets, carried out using the analysis of principal components from the most important physicochemical properties often used to access drug-likeness of compound datasets, showed that the two datasets do not occupy the same chemical space. PMID:27445461

  7. Toxicity assessment of peptaibols and contaminated sediments on Crassostrea gigas embryos.

    Science.gov (United States)

    Poirier, Laurence; Quiniou, Françoise; Ruiz, Nicolas; Montagu, Monique; Amiard, Jean-Claude; Pouchus, Yves François

    2007-08-01

    Peptaibols are known membrane-modifying peptides that were recently detected in marine sediments and mussels collected from a shellfish farming area (Fier d'Ars, Atlantic coast, France). In this investigation, embryotoxicity bioassays with oysters (Crassostrea gigas) were performed to assess acute toxicity of alamethicin and different groups of peptaibols produced by a Trichoderma longibrachiatum strain isolated from marine environment. C. gigas embryos appeared very sensitive to all the metabolites examined with higher toxic effects for long-sequence peptides (EC50 ranging from 10 to 64 nM). D-shaped larvae with mantle abnormality were particularly noticed when peptaibol concentrations increased. Disturbances of embryogenesis were also observed following exposure to organic and aqueous extract of sediments from Fier d'Ars (EC50=42.4 and 6.6 g L(-1) dry weight, respectively). Although peptaibol concentrations measured in these sediments could explain only a part of the toxic effects observed, this study suggests that these mycotoxins can induce larval abnormalities in a population of exposed animals at environmentally realistic concentrations. Their detection in coastal areas devoted to bivalve culture should be taken into account.

  8. Evaluation of usefulness of Microbial Assay for Risk Assessment (MARA) in the cyanobacterial toxicity estimation.

    Science.gov (United States)

    Sieroslawska, Anna

    2014-07-01

    The aim of the study was to elucidate the usefulness of the Microbial Assay for Risk Assessment (MARA) to evaluate toxicity in samples containing cyanobacterial products. Cyanobacterial extracts with different cyanotoxin contents and pure cyanotoxins-microcystin-LR, cylindrospermopsin and anatoxin-a-were tested. On the basis of the microbial reaction, MARA indicated only slight or no toxicity in the studied extracts. Similarly, no or low toxicity of pure toxins was detected at the concentrations used (up to 10 μg/ml). Weak relationships between the reactions of individual organisms exposed to cyanotoxin-containing extracts and to the same pure toxins were observed. On the other hand, inhibition of some organisms, such as Pichia anomalia, whose growth was not impacted by pure cyanotoxins, indicated the presence of other biologically active compounds in the studied extracts. In conclusion, MARA assay is not enough sensitive to be used as a good tool for cyanotoxin screening. It may, however, be applied in searching for antimicrobial/antifungal cyanobacteria-derived compounds. PMID:24682641

  9. Toxicity assessment and modelling of Moringa oleifera seeds in water purification by whole cell bioreporter.

    Science.gov (United States)

    Al-Anizi, Ali Adnan; Hellyer, Maria Theresa; Zhang, Dayi

    2014-06-01

    Moringa oleifera has been used as a coagulation reagent for drinking water purification, especially in developing countries such as Malawi. This research revealed the cytoxicity and genotoxicity of M. oleifera by Acinetobacter bioreporter. The results indicated that significant cytoxicity effects were observed when the powdered M. oleifera seeds concentration is from 1 to 50 mg/L. Through direct contact, ethanolic-water extraction and hexane extraction, the toxic effects of hydrophobic and hydrophilic components in M. oleifera seeds were distinguished. It suggested that the hydrophobic lipids contributed to the dominant cytoxicity, consequently resulting in the dominant genotoxicity in the water-soluble fraction due to limited dissolution when the M. oleifera seeds granule concentration was from 10 to 1000 mg/L. Based on cytoxicity and genotoxicity model, the LC50 and LC90 of M. oleifera seeds were 8.5 mg/L and 300 mg/L respectively and their genotoxicity was equivalent to 8.3 mg mitomycin C per 1.0 g dry M. oleifera seed. The toxicity of M. oleifera has also remarkable synergistic effects, suggesting whole cell bioreporter as an appropriate and complementary tool to chemical analysis for environmental toxicity assessment.

  10. Toxicity assessment of iron oxide nanoparticles in zebrafish (Danio rerio early life stages.

    Directory of Open Access Journals (Sweden)

    Xiaoshan Zhu

    Full Text Available Iron oxide nanoparticles have been explored recently for their beneficial applications in many biomedical areas, in environmental remediation, and in various industrial applications. However, potential risks have also been identified with the release of nanoparticles into the environment. To study the ecological effects of iron oxide nanoparticles on aquatic organisms, we used early life stages of the zebrafish (Danio rerio to examine such effects on embryonic development in this species. The results showed that ≥10 mg/L of iron oxide nanoparticles instigated developmental toxicity in these embryos, causing mortality, hatching delay, and malformation. Moreover, an early life stage test using zebrafish embryos/larvae is also discussed and recommended in this study as an effective protocol for assessing the potential toxicity of nanoparticles. This study is one of the first on developmental toxicity in fish caused by iron oxide nanoparticles in aquatic environments. The results will contribute to the current understanding of the potential ecotoxicological effects of nanoparticles and support the sustainable development of nanotechnology.

  11. The synergistic toxicity of the multiple chemical mixtures: implications for risk assessment in the terrestrial environment.

    Science.gov (United States)

    Chen, Chen; Wang, Yanhua; Qian, Yongzhong; Zhao, Xueping; Wang, Qiang

    2015-04-01

    The combined toxicity of five insecticides (chlorpyrifos, avermectin, imidacloprid, λ-cyhalothrin, and phoxim), two herbicides (atrazine and butachlor) and a heavy metal (cadmium) has been examined with the earthworm acute toxicity test. Toxicological interactions of these chemicals in four, five, six, seven, and eight-component mixtures were studied using the combination-index (CI) equation method. In four-component and five-component mixtures, the synergistic effects predominated at lower effect levels, while the patterns of interactions found in six, seven, and eight-component mixtures displayed synergism. The λ-CY+IMI+BUT+ATR+CPF+PHO combination displayed the most strongly synergistic interaction, with CI values ranging from 0.09 to 0.15. The nature of the interaction changes with the effect level and the relevance of synergistic effects increase with the complexity of the mixture. The CI method was compared with the classical models of concentration addition (CA) and independent action (IA) and we found that the CI method could accurately predict the combined toxicity. The predicted synergism resulted from co-existence of the pesticides and the heavy metal especially at low effect levels may have important implications in risk assessment for the real terrestrial environment.

  12. Pharmacophore modeling and in silico toxicity assessment of potential anticancer agents from African medicinal plants

    Science.gov (United States)

    Ntie-Kang, Fidele; Simoben, Conrad Veranso; Karaman, Berin; Ngwa, Valery Fuh; Judson, Philip Neville; Sippl, Wolfgang; Mbaze, Luc Meva’a

    2016-01-01

    Molecular modeling has been employed in the search for lead compounds of chemotherapy to fight cancer. In this study, pharmacophore models have been generated and validated for use in virtual screening protocols for eight known anticancer drug targets, including tyrosine kinase, protein kinase B β, cyclin-dependent kinase, protein farnesyltransferase, human protein kinase, glycogen synthase kinase, and indoleamine 2,3-dioxygenase 1. Pharmacophore models were validated through receiver operating characteristic and Güner–Henry scoring methods, indicating that several of the models generated could be useful for the identification of potential anticancer agents from natural product databases. The validated pharmacophore models were used as three-dimensional search queries for virtual screening of the newly developed AfroCancer database (~400 compounds from African medicinal plants), along with the Naturally Occurring Plant-based Anticancer Compound-Activity-Target dataset (comprising ~1,500 published naturally occurring plant-based compounds from around the world). Additionally, an in silico assessment of toxicity of the two datasets was carried out by the use of 88 toxicity end points predicted by the Lhasa’s expert knowledge-based system (Derek), showing that only an insignificant proportion of the promising anticancer agents would be likely showing high toxicity profiles. A diversity study of the two datasets, carried out using the analysis of principal components from the most important physicochemical properties often used to access drug-likeness of compound datasets, showed that the two datasets do not occupy the same chemical space. PMID:27445461

  13. From streets to streams: assessing the toxicity potential of urban sediment by particle size

    Science.gov (United States)

    Corsi, Steven R.; Selbig, William R.; Roger T. Bannerman,; ,

    2013-01-01

    Urban sediment can act as a transport mechanism for a variety of pollutants to move towards a receiving water body. The concentrations of these pollutants oftentimes exceed levels that are toxic to aquatic organisms. Many treatment structures are designed to capture coarse sediment but do not work well to similarly capture the fines. This study measured concentrations of select trace metals and PAHs in both the silt and sand fractions of urban sediment from four sources: stormwater bed, stormwater suspended, street dirt, and streambed. Concentrations were used to assess the toxic potential of sediment based on published sediment quality guidelines. All sources of sediment showed some level of toxic potential with stormwater bed sediment the highest followed by stormwater suspended, street dirt, and streambed. Both metal and PAH concentration distributions were highly correlated between the four sampling locations suggesting the presence of one or perhaps only a few sources of these pollutants which remain persistent as sediment is transported from street to stream. Comparison to other forms of combustion- and vehicle-related sources of PAHs revealed coal tar sealants to have the strongest correlation, in both the silt and sand fractions, at all four sampling sites. This information is important for environmental managers when selecting the most appropriate Best Management Practice (BMP) as a way to mitigate pollution conveyed in urban stormwater from source to sink.

  14. Improving ecological risk assessment of persistent, bioaccumulative, and toxic (PBT) chemicals by using an integrated modeling system - An example assessing chloroparaffins in riverine environments.

    Science.gov (United States)

    Chemical risk assessment (CRA) is primarily carried out at the screening level relying on empirical relationships between chemical properties and tested toxicity effects. Ultimately, risk to aquatic ecosystems is strongly dependent on actual exposure, which depends on chemical pr...

  15. Abatement of toxicity of effluents containing Cr(VI) by heterogeneous photocatalysis. Toxicity assessment by AMPHITOX assay.

    Science.gov (United States)

    Hojman, Jonatan Y; Meichtry, J Martín; Litter, Marta I; Pérez Coll, Cristina S

    2015-12-01

    Toxicity of a Cr(VI) solution before and after treatment by TiO2 heterogeneous photocatalysis (HP) was performed with AMPHITOX bioassay. Changes in toxicity on Rhinella arenarum larvae for 10-d were monitored after exposure to an untreated Cr(VI) solution and to the same solution after HP treatment. The HP treatment of a 41.60 mg L(-1) Cr(VI) solution reduced to 37.5% the concentration of the metal ion. A 10-fold reduction in toxicity at acute exposure (72 h) and 150-fold reduction in toxicity after 240 h was found. Further, the LOEC value increased from 0.001% for the untreated solution to 0.153% after HP treatment. Moreover, the safe concentration in untreated solution corresponded to 0.0001% sample, and it was 0.01% after the treatment, i.e., 100 times higher. A saving of water of about 100,000 L per L of effluent would be possible through dilution to allow safer concentrations for discharge; the saving would reach the highest value (1,000,000 L per L) at 240 h. Sub-lethal effects were completely absent in larvae exposed to the treated solution. The AMPHITOX test allowed to detect chronic effects at low Cr concentrations, i.e. at environmentally relevant levels. PMID:26432027

  16. Abatement of toxicity of effluents containing Cr(VI) by heterogeneous photocatalysis. Toxicity assessment by AMPHITOX assay.

    Science.gov (United States)

    Hojman, Jonatan Y; Meichtry, J Martín; Litter, Marta I; Pérez Coll, Cristina S

    2015-12-01

    Toxicity of a Cr(VI) solution before and after treatment by TiO2 heterogeneous photocatalysis (HP) was performed with AMPHITOX bioassay. Changes in toxicity on Rhinella arenarum larvae for 10-d were monitored after exposure to an untreated Cr(VI) solution and to the same solution after HP treatment. The HP treatment of a 41.60 mg L(-1) Cr(VI) solution reduced to 37.5% the concentration of the metal ion. A 10-fold reduction in toxicity at acute exposure (72 h) and 150-fold reduction in toxicity after 240 h was found. Further, the LOEC value increased from 0.001% for the untreated solution to 0.153% after HP treatment. Moreover, the safe concentration in untreated solution corresponded to 0.0001% sample, and it was 0.01% after the treatment, i.e., 100 times higher. A saving of water of about 100,000 L per L of effluent would be possible through dilution to allow safer concentrations for discharge; the saving would reach the highest value (1,000,000 L per L) at 240 h. Sub-lethal effects were completely absent in larvae exposed to the treated solution. The AMPHITOX test allowed to detect chronic effects at low Cr concentrations, i.e. at environmentally relevant levels.

  17. Using Unmanned Aerial Vehicles to Assess Vegetative Cover and Identify Biotic Resources in Sagebrush Steppe Ecosystems: Preliminary Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Robert P. Breckenridge

    2006-04-01

    The Idaho National Laboratory (INL), in conjunction with the University of Idaho, is evaluating novel approaches for using unmanned aerial vehicles (UAVs) as a quicker and safer method for monitoring biotic resources. Evaluating vegetative cover is an important factor in understanding the sustainability of many ecosystems. In assessing vegetative cover, methods that improve accuracy and cost efficiency could revolutionize how biotic resources are monitored on western federal lands. Sagebrush steppe ecosystems provide important habitat for a variety of species, some of which are important indicator species (e.g., sage grouse). Improved methods are needed to support monitoring these habitats because there are not enough resource specialists or funds available for comprehensive ground evaluation of these ecosystems. In this project, two types of UAV platforms (fixed wing and helicopter) were used to collect still-frame imagery to assess cover in sagebrush steppe ecosystems. This paper discusses the process for collecting and analyzing imagery from the UAVs to (1) estimate total percent cover, (2) estimate percent cover for six different types of vegetation, and (3) locate sage grouse based on representative decoys. The field plots were located on the INL site west of Idaho Falls, Idaho, in areas with varying amounts and types of vegetative cover. A software program called SamplePoint developed by the U.S. Department of Agriculture, Agricultural Research Service was used to evaluate the imagery for percent cover for the six vegetation types (bare ground, litter, shrubs, dead shrubs, grasses, and forbs). Results were compared against standard field measurements to assess accuracy.

  18. Health risk assessment of heavy metals in vegetables grown around battery production area

    OpenAIRE

    Ying Chen; Pingping Wu; Yufang Shao; Yibin Ying

    2014-01-01

    Battery production is one of the main sources of heavy metals that present great harm to human health even in low concentrations. Chromium (Cr), Cadmium (Cd) and Lead (Pb) were measured in edible portions of vegetables and soils around a battery production area in China, and the potential health risk of heavy metal contamination to the local population via vegetable consumption was evaluated. Their concentrations in edible portions of vegetables were 2.354 (0.078-14.878), 0.035 (0.003-0.230) ...

  19. Human health risk assessment of heavy metals in soil–vegetable system: A multi-medium analysis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xingmei; Song, Qiujin; Tang, Yu; Li, Wanlu [College of Environmental and Natural Resource Sciences, Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, Zhejiang University, Hangzhou 310058 (China); Xu, Jianming, E-mail: jmxu@zju.edu.cn [College of Environmental and Natural Resource Sciences, Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, Zhejiang University, Hangzhou 310058 (China); Wu, Jianjun, E-mail: wujianjun@zju.edu.cn [College of Environmental and Natural Resource Sciences, Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, Zhejiang University, Hangzhou 310058 (China); Wang, Fan [College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036 (China); Brookes, Philip Charles [College of Environmental and Natural Resource Sciences, Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, Zhejiang University, Hangzhou 310058 (China)

    2013-10-01

    Vegetable fields near villages in China are suffering increasing heavy metal damages from various pollution sources including agriculture, traffic, mining and Chinese typical local private family-sized industry. 268 vegetable samples which included rape, celery, cabbages, carrots, asparagus lettuces, cowpeas, tomatoes and cayenne pepper and their corresponding soils in three economically developed areas of Zhejiang Province, China were collected, and the concentrations of five heavy metals (Pb, Cd, Cr, Hg and As) in all the samples were determined. The health risk assessment methods developed by the United States Environmental Protection Agency (US EPA) were employed to explore the potential health hazards of heavy metals in soils growing vegetables. Results showed that heavy metal contaminations in investigated vegetables and corresponding soils were significant. Pollution levels varied with metals and vegetable types. The highest mean soil concentrations of heavy metals were 70.36 mg kg{sup −1} Pb, 47.49 mg kg{sup −1} Cr, 13.51 mg kg{sup −1} As, 0.73 mg kg{sup −1} for Cd and 0.67 mg kg{sup −1} Hg, respectively, while the metal concentrations in vegetables and corresponding soils were poorly correlated. The health risk assessment results indicated that diet dominated the exposure pathways, so heavy metals in soil samples might cause potential harm through food-chain transfer. The total non-cancer and cancer risk results indicated that the investigated arable fields near industrial and waste mining sites were unsuitable for growing leaf and root vegetables in view of the risk of elevated intakes of heavy metals adversely affecting food safety for local residents. Chromium and Pb were the primary heavy metals posing non-cancer risks while Cd caused the greatest cancer risk. It was concluded that more effective controls should be focused on Cd and Cr to reduce pollution in this study area. - Highlights: • Flourishing private economy caused increasing

  20. Human health risk assessment of heavy metals in soil–vegetable system: A multi-medium analysis

    International Nuclear Information System (INIS)

    Vegetable fields near villages in China are suffering increasing heavy metal damages from various pollution sources including agriculture, traffic, mining and Chinese typical local private family-sized industry. 268 vegetable samples which included rape, celery, cabbages, carrots, asparagus lettuces, cowpeas, tomatoes and cayenne pepper and their corresponding soils in three economically developed areas of Zhejiang Province, China were collected, and the concentrations of five heavy metals (Pb, Cd, Cr, Hg and As) in all the samples were determined. The health risk assessment methods developed by the United States Environmental Protection Agency (US EPA) were employed to explore the potential health hazards of heavy metals in soils growing vegetables. Results showed that heavy metal contaminations in investigated vegetables and corresponding soils were significant. Pollution levels varied with metals and vegetable types. The highest mean soil concentrations of heavy metals were 70.36 mg kg−1 Pb, 47.49 mg kg−1 Cr, 13.51 mg kg−1 As, 0.73 mg kg−1 for Cd and 0.67 mg kg−1 Hg, respectively, while the metal concentrations in vegetables and corresponding soils were poorly correlated. The health risk assessment results indicated that diet dominated the exposure pathways, so heavy metals in soil samples might cause potential harm through food-chain transfer. The total non-cancer and cancer risk results indicated that the investigated arable fields near industrial and waste mining sites were unsuitable for growing leaf and root vegetables in view of the risk of elevated intakes of heavy metals adversely affecting food safety for local residents. Chromium and Pb were the primary heavy metals posing non-cancer risks while Cd caused the greatest cancer risk. It was concluded that more effective controls should be focused on Cd and Cr to reduce pollution in this study area. - Highlights: • Flourishing private economy caused increasing heavy metal damages. • Leafy and

  1. A chronic toxicity test for the tropical marine snail Nassarius dorsatus to assess the toxicity of copper, aluminium, gallium, and molybdenum.

    Science.gov (United States)

    Trenfield, Melanie A; van Dam, Joost W; Harford, Andrew J; Parry, David; Streten, Claire; Gibb, Karen; van Dam, Rick A

    2016-07-01

    Chronic toxicity test methods for assessing the toxicity of contaminants to tropical marine organisms are generally lacking. A 96-h chronic growth rate toxicity test was developed for the larval stage of the tropical dogwhelk, Nassarius dorsatus. Growth rates of N. dorsatus larvae were assessed following exposures to copper (Cu), aluminium (Al), gallium (Ga), and molybdenum (Mo). Exposure to Cu at 28 °C validated the sensitivity of the test method, with 10% (EC10) and 50% (EC50) effect concentrations of 4.2 μg/L and 7.3 μg/L Cu, respectively. The EC10 and EC50 values for Al (toxicity of Cu and Al was also assessed at 24 °C and 31 °C, representing average year-round water temperatures for subtropical and tropical Australian coastal environments. At 24 °C, the growth rate of control larvae was reduced by 52% compared with the growth rate at 28 °C and there was an increase in sensitivity to Cu (EC50 = 4.7 μg/L) but a similar sensitivity to Al (EC50 = 180 μg/L). At 31 °C the control growth rate increased by 35% from that measured at 28 °C and there was reduced sensitivity to both Cu and Al (EC50s = 8.5 μg/L and 642 μg/L, respectively). There was minimal toxicity resulting from Ga (EC50 = 4560 μg/L) and Mo (no effect at ≤7000 μg/L Mo). Environ Toxicol Chem 2016;35:1788-1795. © 2015 SETAC.

  2. DEVELOPMENT OF AN INDEX OF ALIEN SPECIES INVASIVENESS: AN AID TO ASSESSING RIPARIAN VEGETATION CONDITION

    Science.gov (United States)

    Many riparian areas are invaded by alien plant species that negatively affect native species composition, community dynamics and ecosystem properties. We sampled vegetation along reaches of 31 low order streams in eastern Oregon, and characterized species assemblages at patch an...

  3. Assessment of impacts of visitors' activities on vegetation in Zhangjiajie National Forest Park

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In three scenic spots (Golden Whip Crag, General Rock, and Treasure Box for Celestial Books) of Zhangjiajie National Forest Park, four sample plots were selected to investigate the number of tree skin scars damaged by visitors and the quantity and species of vegetation. The analysis results indicated that trees located along the sides of roads are seriously cut by visitors, especially in Yellowstone Village and Gold Whip Stream areas. The wounded degree was mainly related to tree species, smoothing degree, and the distance from tree to the edge of roads. The impacting degree of tourism activities on vegetation was confirmed by Impact Vegetation Index (IVI). On the three most visually impacts sites, the range of IVI value varied from 59.4% to 87.5%. This showed that the vegetations of the sides of the trails were impacted seriously. To these problems, some suggestions are proposed for the park's management on visitors.

  4. Environmental Assessment Marsh Vegetation Rehabilitation Chemical Control of Phragmites at Prime Hook National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This proposal describes a rehabilitation program for up to 3,000 acres of marsh vegetation. The primary objectives are: 1) to chemically control the dense stands of...

  5. Cedar Breaks National Monument Vegetation Mapping Project - Field Plot, Observation Points and Accuracy Assessment Points

    Data.gov (United States)

    National Park Service, Department of the Interior — This point file contains 282 point locations of field plot and observation data used by, and collected for, the vegetation mapping project for Cedar Breaks National...

  6. Safety Evaluation of Turmeric Polysaccharide Extract: Assessment of Mutagenicity and Acute Oral Toxicity

    Directory of Open Access Journals (Sweden)

    Chandrasekaran Chinampudur Velusami

    2013-01-01

    Full Text Available Curcuma longa Linn. (Zingiberaceae commonly known as turmeric has long been used for centuries as a spice and household remedy. The present study was carried out to assess the possible mutagenic potential and acute oral toxicity of polysaccharide extract of turmeric rhizome (NR-INF-02 using standard tests. The standard battery of in vitro genotoxicity tests, bacterial reverse mutation test (BRMT, chromosome aberration (CA, and micronucleus (MN tests were employed to assess the possible mutagenic activity of NR-INF-02 (Turmacin. The results showed no mutagenic effect with NR-INF-02 up to a dose of 5000 µg/mL in BRMT. The results on CA and MN tests revealed the non clastogenic activity of NR-INF-02 in a dose range of 250.36 to 2500 µg/mL with and without metabolic activation (S9. In acute oral toxicity study, NR-INF-02 was found to be safe up to 5 g/kg body weight in Wistar rats. Overall, results indicated that polysaccharide extract of C. longa was found to be genotoxically safe and also exhibited maximum tolerable dose of more than 5 g/kg rat body weight.

  7. An integrated assessment of wild vegetable resources in Inner Mongolian Autonomous Region, China

    OpenAIRE

    Wujisguleng Wujisguleng; Khasbagen Khasbagen

    2010-01-01

    Abstract Background This paper was based on ethnobotanical investigations conducted from 2004-2006 in Inner Mongolian Autonomous Region of northern China. Today, due to their nutritious and relatively pollution-free characteristics, wild vegetables are playing an increasingly important role in peoples' health and well-being. This paper aims to provide scientific clues for the selection of special and high quality wild vegetables species. Methods An ethnobotanical study, consisting of a litera...

  8. Transfer of metals from soil to vegetables and possible health risk assessment

    OpenAIRE

    Jolly, Yeasmin Nahar; Islam, Ashraful; Akbar, Shawkat

    2013-01-01

    Metal contamination in agricultural soils is of increasing concern due to food safety issues and potential health risks. Accumulation of Heavy and trace metals in vegetables occur by various sources but soil is considered the major one. Consumption of vegetables containing (heavy/trace) metals is one of the main ways in which these elements enter the human body. Once entered, heavy metals are deposited in bone and fat tissues, overlapping noble minerals and cause an array of diseases. The pre...

  9. Assessment of Trace Metal Levels in Commonly Edible Vegetables from Selected Markets in Lagos State, Nigeria

    Directory of Open Access Journals (Sweden)

    Adu, A.A

    2014-12-01

    Full Text Available Consumption of food contaminated with heavy metals is a major source of health problems for man and animals. Three commonly edible Leafy vegetables (Amaranthus hybridus, Celosia argentea ,Cochorus olitoris from Agboju and Iba markets , Lagos Nigeria were sampled, identified, digested and analyzed with the aid of Atomic Absorption Spectrophotometer (AAS as directed by APHA (American Public Health Association to determine heavy metals concentration in them with the aim of ascertaining their edibility for human consumption. The mean concentration for each heavy metal in the samples gotten from each market were calculated, the comparison of these data was done amongst the two markets, and compared with the permissible levels set by the FAO and WHO. The results showed that the levels of Lead, Cadmium, Copper, Zinc, Iron, Nickel, Selenium and Chromiumpresent in the vegetable concentrated in the following order Fe>Pb>Zn>Cd>Ni>Cu>Cr>Se. With regards to vegetables in questions, analysis of variance showed that some vegetables accumulated metals more than each other and as such indicated that metals like copper, cadmium, selenium, iron and zinc are significant at P0.05.With significant values of lead, cadmium and nickel, recorded in both Amaranthus hybridus and Celosia argenteavegetables, vegetables consumers must be weary of vegetables to buy and the market that is save to buy from, especially markets located very close to highways or close to major busy roads .

  10. Limitations of toxicity characterization in life cycle assessment: Can adverse outcome pathways provide a new foundation?

    Science.gov (United States)

    Gust, Kurt A; Collier, Zachary A; Mayo, Michael L; Stanley, Jacob K; Gong, Ping; Chappell, Mark A

    2016-07-01

    Life cycle assessment (LCA) has considerable merit for holistic evaluation of product planning, development, production, and disposal, with the inherent benefit of providing a forecast of potential health and environmental impacts. However, a technical review of current life cycle impact assessment (LCIA) methods revealed limitations within the biological effects assessment protocols, including: simplistic assessment approaches and models; an inability to integrate emerging types of toxicity data; a reliance on linear impact assessment models; a lack of methods to mitigate uncertainty; and no explicit consideration of effects in species of concern. The purpose of the current study is to demonstrate that a new concept in toxicological and regulatory assessment, the adverse outcome pathway (AOP), has many useful attributes of potential use to ameliorate many of these problems, to expand data utility and model robustness, and to enable more accurate and defensible biological effects assessments within LCIA. Background, context, and examples have been provided to demonstrate these potential benefits. We additionally propose that these benefits can be most effectively realized through development of quantitative AOPs (qAOPs) crafted to meet the needs of the LCIA framework. As a means to stimulate qAOP research and development in support of LCIA, we propose 3 conceptual classes of qAOP, each with unique inherent attributes for supporting LCIA: 1) mechanistic, including computational toxicology models; 2) probabilistic, including Bayesian networks and supervised machine learning models; and 3) weight of evidence, including models built using decision-analytic methods. Overall, we have highlighted a number of potential applications of qAOPs that can refine and add value to LCIA. As the AOP concept and support framework matures, we see the potential for qAOPs to serve a foundational role for next-generation effects characterization within LCIA. Integr Environ Assess Manag

  11. Is Boric Acid Toxic to Reproduction in Humans? Assessment of the Animal Reproductive Toxicity Data and Epidemiological Study Results.

    Science.gov (United States)

    Duydu, Yalçın; Başaran, Nurşen; Ustündağ, Aylin; Aydın, Sevtap; Undeğer, Ulkü; Ataman, Osman Yavuz; Aydos, Kaan; Düker, Yalçın; Ickstadt, Katja; Waltrup, Brita Schulze; Golka, Klaus; Bolt, Hermann Maximilian

    2016-01-01

    Boric acid and sodium borates are classified as toxic to reproduction in the CLP Regulation under "Category 1B" with the hazard statement of "H360FD". This classification is based on the reprotoxic effects of boric acid and sodium borates in animal experiments at high doses. However, boron mediated reprotoxic effects have not been proven in epidemiological studies so far. The epidemiological study performed in Bandırma boric acid production plant is the most comprehensive published study in this field with 204 voluntarily participated male workers. Sperm quality parameters (sperm morphology, concentration and motility parameters), FSH, LH and testosterone levels were determined in all participated employees as the reproductive toxicity biomarkers of males. However, boron mediated unfavorable effects on reproduction in male workers have not been determined even in the workers under very high daily boron exposure (0.21 mg B/kg-bw/day) conditions. The NOAEL for rat reproductive toxicity is equivalent to a blood boron level of 2020 ng/g. This level is higher than the mean blood boron concentration (223.89 ± 69.49 ng/g) of the high exposure group workers in Bandırma boric acid production plant (Turkey) by a factor of 9. Accordingly, classifying boric acid and sodium borates under "Category 1B" as "presumed reproductive human toxicant in the CLP regulation seems scientifically not reasonable. The results of the epidemiological studies (including the study performed in China) support for a down-classification of boric acid from the category 1B, H360FD to category 2, H361d, (suspected of damaging the unborn child).

  12. Assessment of compost application to coal ash disposal sites to promote the rapid vegetation establishment

    Science.gov (United States)

    Repmann, F.; Slazak, A.; Babic, M.; Schneider, B. U.; Schaaf, W.; Hüttl, R. F.

    2009-04-01

    In the city of Tuzla, located in Bosnia and Herzegovina, a coal fired thermo electric power plant is operated by the company JP ELEKTROPRIVERDA BIH TERMOELEKTRANA "TUZLA". High amounts of ash are produced by the power plant, which are currently disposed into settlement ponds bordered by dams in natural valleys. A total of four ash disposal sites covering an area of approx. 170 ha have been established during the last decades. Due to the fact that residual ash from coal combustion was found to contain a variety of trace elements (Ni, Cr, As, B), it must be assumed that ash disposal of that magnitude constitutes an environmental problem which is investigated within the EU-FP6 / STREP project "Reintegration of Coal Ash Disposal Sites and Mitigation of Pollution in the West Balkan Area" RECOAL. The main hazards relate to soil and groundwater contamination due to leaching toxins, dust dispersion, and toxins entering the food chain as these disposal sites are used for agricultural purposes. In order to rapidly establish a vegetation cover on barren ash dumps that particularly would prevent dust erosion we assessed the applicability of compost, produced from locally available municipal and industrial organic residues as an amendment to ash to improve substrate fertility. The envisaged remediation technology was considered to be a low cost, easy applicable and rapid method capable of substantially enhancing living conditions of residents in the vicinity of the abandoned disposal sites. Various compost application rates were evaluated in the field on experimental site Divkovici I in Tuzla and additionally in the greenhouse environment at Brandenburg Technical University Cottbus. Field and laboratory tests revealed that plant growth and cover rate can substantially be improved by mixing compost into the upper ash layer to a maximum depth of approx. 20 cm. Besides direct growth observations in the field analysis of soil parameters gave evidence that the fertility of ashy

  13. Fetal functional brain age assessed from universal developmental indices obtained from neuro-vegetative activity patterns.

    Directory of Open Access Journals (Sweden)

    Dirk Hoyer

    Full Text Available Fetal brain development involves the development of the neuro-vegetative (autonomic control that is mediated by the autonomic nervous system (ANS. Disturbances of the fetal brain development have implications for diseases in later postnatal life. In that context, the fetal functional brain age can be altered. Universal principles of developmental biology applied to patterns of autonomic control may allow a functional age assessment. The work aims at the development of a fetal autonomic brain age score (fABAS based on heart rate patterns. We analysed n = 113 recordings in quiet sleep, n = 286 in active sleep, and n = 29 in active awakeness from normals. We estimated fABAS from magnetocardiographic recordings (21.4-40.3 weeks of gestation preclassified in quiet sleep (n = 113, 63 females and active sleep (n = 286, 145 females state by cross-validated multivariate linear regression models in a cross-sectional study. According to universal system developmental principles, we included indices that address increasing fluctuation range, increasing complexity, and pattern formation (skewness, power spectral ratio VLF/LF, pNN5. The resulting models constituted fABAS. fABAS explained 66/63% (coefficient of determination R(2 of training and validation set of the variance by age in quiet, while 51/50% in active sleep. By means of a logistic regression model using fluctuation range and fetal age, quiet and active sleep were automatically reclassified (94.3/93.1% correct classifications. We did not find relevant gender differences. We conclude that functional brain age can be assessed based on universal developmental indices obtained from autonomic control patterns. fABAS reflect normal complex functional brain maturation. The presented normative data are supplemented by an explorative study of 19 fetuses compromised by intrauterine growth restriction. We observed a shift in the state distribution towards active awakeness. The lower WGA

  14. Assessing the impact of climate variability on catchment water balance and vegetation cover

    Directory of Open Access Journals (Sweden)

    X. Xu

    2011-06-01

    Full Text Available Understanding the interactions among climate, vegetation cover and the water cycle lies at the heart of the study of watershed ecohydrology. Recently, considerable attention is being paid to the effect of climate variability (e.g., precipitation and temperature on catchment water balance and also associated vegetation cover. In this paper, we investigate the general pattern of long-term water balance and vegetation cover (as reflected in fPAR among 193 study catchments in Australia through statistical analysis. We then employ the elasticity analysis approach for quantifying the effects of climate variability on hydrologic partitioning (including total runoff, surface and subsurface runoff and on vegetation cover (including total, woody and non-woody vegetation cover. Based on the results of statistical analysis, we conclude that annual runoff (R, evapotranspiration (E and runoff coefficient (R/P all increase with vegetation cover for catchments in which woody vegetation is dominant and annual precipitation is relatively high. Annual evapotranspiration (E is mainly controlled by water availability rather than energy availability for catchments in relatively dry climates in which non-woody vegetation is dominant. The ratio of subsurface runoff to total runoff (Rg/R also increases with woody vegetation cover. Through the elasticity analysis of catchment runoff, it is shown that precipitation (P in the current year is the most important factor affecting the change in annual total runoff (R, surface runoff (Rs and subsurface runoff (Rg. The significance of other controlling factors is in the order of the annual precipitation in the previous year (P−1 and P−2, which represent the net effect of soil moisture, and the annual mean temperature (T in the current year. Change of P by +1 % causes a +3

  15. Fungidice Risk Assessment for Aquatic Ecosystems: Importance of Interspecific Variation, Toxic Mode of Action, and Exposure Regime

    NARCIS (Netherlands)

    Maltby, L.; Brock, T.C.M.; Brink, van den P.J.

    2009-01-01

    The risk assessment of fungicides in Europe uses information from ecotoxicity studies performed on vertebrates, invertebrates, and primary producers, but not nontarget fungi. But which toxicity data should be used to assess risk and how important are modes of action and exposure regimes? A data set

  16. Assessing vulnerability to vegetation growth on earth dikes using geophysical investigation

    Science.gov (United States)

    Mary, Benjamin; Saracco, Ginette; Peyras, Laurent; Vennetier, Michel; Mériaux, Patrice

    2015-04-01

    The Mediterranean Basin is prone to a plethora of natural hazards including floods. Vegetation growth in hydraulic earth structures, such as flood protections or channel levees and dams, may induce several degradation mechanisms leading to a risk of failure. Typically, trees' rooting generates two types of risks: internal erosion from root development in earth embankments, and external erosion (slopes and crest) which is often related to trees uprooting. To better assess how woody vegetation can compromise levee integrity, we designed a methodology using acoustical and complex electrical tomography as non destructives methods to spot dangerous roots in the embankment. Our work has been first initiated during laboratory experiments; we performed soundings in controlled conditions to determine both acoustical and electrical intrinsic behavior of our root samples. By comparison with soil samples we expected to point out specific signatures that would be useful for the roots anomaly identification in real conditions. Measurements were repeated on several samples to ensure statistical interpretation. With help of an ultrasonic transmission device, we identified significant relative velocity differences of compressional waves propagation between soil and root samples. We also studied spectral properties using wavelet processing method as an additional parameter of root distinction with the surrounding soil. In the case of electrical soundings, complex resistivity was measured and we computed resistivity spectra. Amplitude of resistivity term showed us that root material behaves as an insulator compared to the soil. With the phase resistivity term information, root can also be seen as an electric power capacitance and reveals maximum polarization effect located around 1Hz. Then, as experimental device for the field measurements, we selected a 320 cm high poplar (Populus) planted in a homogeneous loamy-clayed soil, which is the same soil used in laboratory experiment to

  17. Effect of Low pH and Aluminum Toxicity on the Photosynthetic Characteristics of Different Fast-Growing Eucalyptus Vegetatively Propagated Clones.

    Directory of Open Access Journals (Sweden)

    Mei Yang

    Full Text Available Knowing how acid soils and aluminum in soils may limit the growth of Eucalyptus trees in plantations is important because these plantations grow in many tropical and subtropical regions. Seedlings of four vegetatively propagated Eucalyptus clones, E. grandis × E. urophylla 'GLGU9'(G9, E. grandis × E. urophylla 'GLGU12' (G12, E. urophylla × E. camaldulensis 'GLUC3' (G3 and E. urophylla 'GLU4'(G4, were subjected to liquid culture with Hoagland nutrient solution for 40 days, then treated with four different treatments of acid and aluminum for 1 day. The four treatments used either pH 3.0 or 4.0 with or without added aluminum (4.4 mM in all possible combinations; a control used no added aluminum at pH 4.8. Subsequently, the photosynthetic parameters and morphology of leaves from eucalypt seedlings were determined and observed. The results showed that the tested chlorophyll content, net photosynthetic rate, transpiration rate and water use efficiency were apparently inhibited by aluminum. Under uniform Al concentration (4.4 mM, the Al-induced limitation to photosynthetic parameters increased with pH, indicating acid stimulation to Al toxicity. Among all treatments, the most significant reduction was found in the combination of pH 3.0 and 4.4 mM Al. The photosynthetic and transpiration rates showed similar trends with G9 > G12 > G3 > G4, suggesting that G9 and G12 had higher Al-tolerance than other two clones. Microscopic observation revealed changes in leaf morphology when exposed to Al stress; for example, a reduced thickness of leaf epidermis and palisade tissue, the descendant palisade tissue/spongy tissue ratio and leaf tissue looseness. Overall, the acid and aluminum stress exerted negative effects on the photosynthetic activity of eucalypt seedlings, but the differences in tolerance to Al toxicity between the clones were favorable, offering potential to improve Eucalyptus plantation productivity by selecting Al tolerant clones.

  18. Health risk assessment of heavy metals in soils and vegetables from wastewater irrigated area, Beijing-Tianjin city cluster, China

    Institute of Scientific and Technical Information of China (English)

    Yanchun Wang; Min Qiao; Yunxia Liu; Yongguan Zhu

    2012-01-01

    The possible health risks of heavy metals contamination to local population through food chain were evaluated in Beijing and Tianjin city cluster,China,where have a long history of sewage irrigation.The transfer factors (TF) for heavy metals from soil to vegetables for six elements including Cu,Zn,Pb,Cr,As and Cd were calculated and the pollution load indexes (PLI) were also assessed.Results indicate that only Cd exceeded the maximum acceptable limit in these sites.So far,the heavy metal concentrations in soils and vegetables were all below the permissible limits set by the Ministry of Environmental Protection of China and World Health Organization.The transfer factors of six heavy metals showed the trend as Cd > Zn > Cu > Pb > As > Cr,which were dependent on the vegetable species.The estimated dietary intakes of Cu,Zn,Pb,Cr,As and Cd were far below the tolerable limits and the target hazard quotient (THQ) values were less than 1,which suggested that the health risks of heavy metals exposure through consuming vegetables were generally assumed to be safe.

  19. Assessment of groundwater input and water quality changes impacting natural vegetation in the Loxahatchee River and floodplain ecosystem, Florida

    Science.gov (United States)

    Orem, William H.; Swarzenski, Peter W.; McPherson, Benjamin F.; Hedgepath, Marion; Lerch, Harry E.; Reich, Christopher; Torres, Arturo E.; Corum, Margo D.; Roberts, Richard E.

    2007-01-01

    The Loxahatchee River and Estuary are small, shallow, water bodies located in southeastern Florida. Historically, the Northwest Branch (Fork) of the Loxahatchee River was primarily a freshwater system. In 1947, the river inlet at Jupiter was dredged for navigation and has remained permanently open since that time. Drainage patterns within the basin have also been altered significantly due to land development, road construction (e.g., Florida Turnpike), and construction of the C-18 and other canals. These anthropogenic activities along with sea level rise have resulted in significant adverse impacts on the ecosystem over the last several decades, including increased saltwater encroachment and undesired vegetation changes in the floodplain. The problem of saltwater intrusion and vegetation degradation in the Loxahatchee River may be partly induced by diminished freshwater input, from both surface water and ground water into the River system. The overall objective of this project was to assess the seasonal surface water and groundwater interaction and the influence of the biogeochemical characteristics of shallow groundwater and porewater on vegetation health in the Loxahatchee floodplain. The hypothesis tested are: (1) groundwater influx constitutes a significant component of the overall flow of water into the Loxahatchee River; (2) salinity and other chemical constituents in shallow groundwater and porewater of the river floodplain may affect the distribution and health of the floodplain vegetation.

  20. Assessing the impact of climate variability on catchment water balance and vegetation cover

    Directory of Open Access Journals (Sweden)

    X. Xu

    2012-01-01

    Full Text Available Understanding the interactions among climate, vegetation cover and the water cycle lies at the heart of the study of watershed ecohydrology. Recently, considerable attention is being paid to the effect of climate variability on catchment water balance and also associated vegetation cover. In this paper, we investigate the general pattern of long-term water balance and vegetation cover (as reflected by fPAR among 193 study catchments in Australia through statistical analysis. We then employ the elasticity analysis approach for quantifying the effects of climate variability on hydrologic partitioning (including total, surface and subsurface runoff and on vegetation cover (including total, woody and non-woody vegetation cover. Based on the results of statistical analysis, we conclude that annual runoff (R, evapotranspiration (E and runoff coefficient (R/P increase with vegetation cover for catchments in which woody vegetation is dominant and annual precipitation is relatively high. Control of water available on annual evapotranspiration in non-woody dominated catchments is relatively stronger compared to woody dominated ones. The ratio of subsurface runoff to total runoff (Rg/R also increases with woody vegetation cover. Through the elasticity analysis of catchment runoff, it is shown that precipitation (P in current year is the most important factor affecting the change in annual total runoff (R, surface runoff (Rs and subsurface runoff (Rg. The significance of other controlling factors is in the order of annual precipitation in previous years (P−1 and P−2, which represents the net effect of soil moisture and annual mean temperature (T in current year. Change of P by +1% causes a +3.35% change of R, a +3.47% change of Rs and a +2.89% change of

  1. Risk Assessment of Heavy Metal Contamination on Vegetables Grown in Long-term Wastewater Irrigated Urban Farming Sites in Accra, Ghana

    DEFF Research Database (Denmark)

    Lente, I.; Keraita, Bernard; Drechsel, P.;

    2012-01-01

    Assessment was done of heavy-metal contamination and its related health risks in urban vegetable farming in Accra. Samples of irrigation water (n = 120), soil (n = 144) and five different kinds of vegetable (n = 240) were collected and analyzed for copper, zinc, lead, cadmium, chromium, nickel...... higher. Health risk assessments showed for all elements that normal consumption of each of the vegetables assessed poses no risk. The highest hazard index obtained was 42 % for wastewater irrigated cabbage. Though within permissible limits, cabbage and ayoyo had the highest potential risk. Compared...

  2. Selection of a bioassay battery to assess toxicity in the affluents and effluents of three water-treatment plants

    OpenAIRE

    Paola Bohórquez-Echeverry; Marcela Duarte-Castañeda; Nubia León-López; Claudia Campos-Pinilla; Fabián Caicedo-Carrascal; Myriam Vásquez-Vásquez

    2012-01-01

    The assessment of water quality includes the analysis of both physical-chemical and microbiological parameters. However,none of these evaluates the biological effect that can be generated in ecosystems or humans. In order to define the most suitable organismsto evaluate the toxicity in the affluent and effluent of three drinking-water treatment plants, five acute toxicity bioassays were used,incorporating three taxonomic groups of the food chain. Materials and methods. The bioassays used were...

  3. Assessing vegetation changes in timberline ecotone of Nanda Devi National Park, Uttarakhand

    Science.gov (United States)

    Bharti, Rupesh R.; Adhikari, Bhupendra S.; Rawat, Gopal S.

    2012-08-01

    Changes in the timberline ecotone vegetation of Nanda Devi National Park (NDNP) was studied over a period of 30 years (1980-2010). Our study based on remote sensing analysis of Landsat MSS and TM images suggests no geographical shift in the upper limit of timberline, while the subalpine forest's canopy has increased substantially. Decrease in heterogeneous reflectance pattern near upper boundary of timberline ecotone (above 3600 m asl) suggest more homogenous growth at this elevation. Though the scale of the study is not sufficient to detect minor changes our objective here is to know if the timberline vegetation of NDNP has gone under rapid change in last three decades. Two different methods post classification comparison and vegetation index differencing, used in this study have widely been used for vegetation change detection but very few studies have reported the performance of these methods for highly rugged terrain. Our approach in this study is to test the applicability of these methods in the specific environment of western Himalaya. Given the fact that the findings of the study could be the result of incorporation of various methodological errors we analyzed the descriptive statistics (mean and standard deviation) of vegetation index to interpret the nature of change.

  4. Global assessment of experimental climate warming on tundra vegetation: heterogeneity over space and time.

    Science.gov (United States)

    Elmendorf, Sarah C; Henry, Gregory H R; Hollister, Robert D; Björk, Robert G; Bjorkman, Anne D; Callaghan, Terry V; Collier, Laura Siegwart; Cooper, Elisabeth J; Cornelissen, Johannes H C; Day, Thomas A; Fosaa, Anna Maria; Gould, William A; Grétarsdóttir, Járngerður; Harte, John; Hermanutz, Luise; Hik, David S; Hofgaard, Annika; Jarrad, Frith; Jónsdóttir, Ingibjörg Svala; Keuper, Frida; Klanderud, Kari; Klein, Julia A; Koh, Saewan; Kudo, Gaku; Lang, Simone I; Loewen, Val; May, Jeremy L; Mercado, Joel; Michelsen, Anders; Molau, Ulf; Myers-Smith, Isla H; Oberbauer, Steven F; Pieper, Sara; Post, Eric; Rixen, Christian; Robinson, Clare H; Schmidt, Niels Martin; Shaver, Gaius R; Stenström, Anna; Tolvanen, Anne; Totland, Orjan; Troxler, Tiffany; Wahren, Carl-Henrik; Webber, Patrick J; Welker, Jeffery M; Wookey, Philip A

    2012-02-01

    Understanding the sensitivity of tundra vegetation to climate warming is critical to forecasting future biodiversity and vegetation feedbacks to climate. In situ warming experiments accelerate climate change on a small scale to forecast responses of local plant communities. Limitations of this approach include the apparent site-specificity of results and uncertainty about the power of short-term studies to anticipate longer term change. We address these issues with a synthesis of 61 experimental warming studies, of up to 20 years duration, in tundra sites worldwide. The response of plant groups to warming often differed with ambient summer temperature, soil moisture and experimental duration. Shrubs increased with warming only where ambient temperature was high, whereas graminoids increased primarily in the coldest study sites. Linear increases in effect size over time were frequently observed. There was little indication of saturating or accelerating effects, as would be predicted if negative or positive vegetation feedbacks were common. These results indicate that tundra vegetation exhibits strong regional variation in response to warming, and that in vulnerable regions, cumulative effects of long-term warming on tundra vegetation - and associated ecosystem consequences - have the potential to be much greater than we have observed to date.

  5. [Contamination of Organophosphorus Pesticides Residue in Fresh Vegetables and Related Health Risk Assessment in Changchun, China].

    Science.gov (United States)

    Yu, Rui; Liu, Jing-shuang; Wang, Qi-cun; Liu, Qiang; Wang, Yang

    2015-09-01

    This study aims to investigate the concentrations of organophosphorus pesticides (OPs) in fresh vegetables. A total of Z14 samples from seven types of vegetables were collected from the suburb in Changchun City. The OPs were analyzed by gas chromatography coupled with flame photometric detector (GC-FPD). Target hazard quotients (THQ) were applied to estimate the potential health risk to inhabitants. Results showed that OPs concentrations exceeded the Maximum Residue Limit (MRL) in more than 23. 4% samples, and were not detected in only 7. 9% samples. Detection rates of OPs was as follow in the decreased order: diazinon (82. 2%) > phorate (45. 8%) > dimethoate (29. 4%) > parathion-methyl (27. 6%) > omethoate (23. 8%) > dichlorvos (22. 9%) > fenitrothion (21%) > fenthion (18. 7%) > parathion (18. 2%) > methamidophos (17. 3%) > malathion (12. 1%). The percentages above MRL for leaves were higher than for non-leafy vegetables. The order of percentages of OPs above MRL was as follows: green onion (82. 5%) > radish (37. 5%) > red pepper (17. 2%) > Chinese vegetable (14. 3%) > cucumber (3. 2%) > eggplant (2. 9%) > tomato (0%). 49. 5% vegetables samples showed more than one OP. The average target hazard quotients (ave THQ) were all less than one and the average Hazard Index (ave HI) was 0. 462, so that inhabitants who expose average OP levels may not experience adverse health effects.

  6. Assessing water stress of desert vegetation using remote sensing : the case of the Tamarugo forest in the Atacama Desert (Northern Chile)

    NARCIS (Netherlands)

    Chávez Oyanadel, R.O.

    2014-01-01

    Water stress assessment of natural vegetation plays a key role in water management of desert ecosystems. It allows scientists and managers to relate water extraction rates to changes in vegetation water condition, and consequently to define safe water extraction rates for maintaining a healthy ecosy

  7. [Assessment of chlorophyll content using a new vegetation index based on multi-angular hyperspectral image data].

    Science.gov (United States)

    Liao, Qin-hong; Zhang, Dong-yan; Wang, Ji-hua; Yang, Gui-jun; Yang, Hao; Coburn, Craig; Wong, Zhijie; Wang, Da-cheng

    2014-06-01

    The fast estimation of chlorophyll content is significant for understanding the crops growth, monitoring the disease and insect, and assessing the yield of crops. This study gets the hyperspectral imagery data by using a self-developed multi-angular acquisition system during the different maize growth period, the reflectance of maize canopy was extracted accurately from the hyperspectral images under different view angles in the principal plane. The hot-dark-spot index (HDS) of red waveband was calculated through the analysis of simulated values by ACRM model and measured values, then this index was used to modify the vegetation index (TCARI), thus a new vegetation index (HD-TCARI) based on the multi-angular observation was proposed. Finally, the multi-angular hyperspectral imagery data was used to validate the vegetation indexes. The result showed that HD-TCARI could effectively reduce the LAI effects on the assessment of chlorophyll content. When the chlorophyll content was greater than 30 μg x cm(-2), the correlation (R2) between HD-TCARI and LAI was only 26.88%-28.72%. In addition, the HD-TCARI could resist the saturation of vegetation index during the assessment of high chlorophyll content. When the LAI varled from 1 to 6, the linear relation between HD-TCARI and chlorophyll content could be improved by 9% compared with TCARI. The ground validation of HD-TCARI by multi-angular hyperspectral image showed that the linear relation between HD-TCARI and chlorophyll content (R2 = 66.74%) was better than the TCARI (R2 = 39.92%), which indicated that HD-TCARI has good potentials for estimating the chlorophyll content.

  8. Assessment of Fruit and Vegetable Losses at Major Wholesale Markets in Nepal

    Directory of Open Access Journals (Sweden)

    A. R. Devkota

    2014-12-01

    Full Text Available A study regarding the losses of harvested horticultural produces in the major fruit and vegetable wholesale markets of Nepal was conducted to identify the major causes of fruits and vegetable wastage. This study aimed at generating useful information about the causes of loss of horticultural produce, types of loss and also about the possibility of reuse and recycling of such organic wastes as resource for composting and vermicomposting. Survey of the three major market centers namely; Narayangadh, Pokhara, and Kalimati fruit and vegetable wholesale market was conducted. Forty five wholesalers and 90 retailers were selected for the study. Data were collected using structured questionnaires. From regression analysis it was concluded that lack of cold storage facility and inappropriate packaging facility had significant effect on the loss of the produce.

  9. A multitemporal and non-parametric approach for assessing the impacts of drought on vegetation greenness

    DEFF Research Database (Denmark)

    Carrao, Hugo; Sepulcre, Guadalupe; Horion, Stéphanie Marie Anne F;

    2013-01-01

    for the period between 1998 and 2010. The time-series analysis of vegetation greenness is performed during the growing season with a non-parametric method, namely the seasonal Relative Greenness (RG) of spatially accumulated fAPAR. The Global Land Cover map of 2000 and the GlobCover maps of 2005/2006 and 2009......This study evaluates the relationship between the frequency and duration of meteorological droughts and the subsequent temporal changes on the quantity of actively photosynthesizing biomass (greenness) estimated from satellite imagery on rainfed croplands in Latin America. An innovative non...... Full Data Reanalysis precipitation time-series product, which ranges from January 1901 to December 2010 and is interpolated at the spatial resolution of 1° (decimal degree, DD). Vegetation greenness composites are derived from 10-daily SPOT-VEGETATION images at the spatial resolution of 1/112° DD...

  10. A tiered approach for the human health risk assessment for consumption of vegetables from with cadmium-contaminated land in urban areas.

    Science.gov (United States)

    Swartjes, Frank A; Versluijs, Kees W; Otte, Piet F

    2013-10-01

    Consumption of vegetables that are grown in urban areas takes place worldwide. In developing countries, vegetables are traditionally grown in urban areas for cheap food supply. In developing and developed countries, urban gardening is gaining momentum. A problem that arises with urban gardening is the presence of contaminants in soil, which can be taken up by vegetables. In this study, a scientifically-based and practical procedure has been developed for assessing the human health risks from the consumption of vegetables from cadmium-contaminated land. Starting from a contaminated site, the procedure follows a tiered approach which is laid out as follows. In Tier 0, the plausibility of growing vegetables is investigated. In Tier 1 soil concentrations are compared with the human health-based Critical soil concentration. Tier 2 offers the possibility for a detailed site-specific human health risk assessment in which calculated exposure is compared to the toxicological reference dose. In Tier 3, vegetable concentrations are measured and tested following a standardized measurement protocol. To underpin the derivation of the Critical soil concentrations and to develop a tool for site-specific assessment the determination of the representative concentration in vegetables has been evaluated for a range of vegetables. The core of the procedure is based on Freundlich-type plant-soil relations, with the total soil concentration and the soil properties as variables. When a significant plant-soil relation is lacking for a specific vegetable a geometric mean of BioConcentrationFactors (BCF) is used, which is normalized according to soil properties. Subsequently, a 'conservative' vegetable-group-consumption-rate-weighted BioConcentrationFactor is calculated as basis for the Critical soil concentration (Tier 1). The tool to perform site-specific human health risk assessment (Tier 2) includes the calculation of a 'realistic worst case' site-specific vegetable

  11. Assessment of Fluoride Concentration of Soil and Vegetables in Vicinity of Zinc Smelter, Debari, Udaipur, Rajasthan

    Science.gov (United States)

    Bhat, Nagesh; Asawa, Kailash; Tak, Mridula; Shinde, Kushal; Singh, Anukriti; Gandhi, Neha; Gupta, Vivek Vardhan

    2015-01-01

    Background As of late, natural contamination has stimulated as a reaction of mechanical and other human exercises. In India, with the expanding industrialization, numerous unsafe substances are utilized or are discharged amid generation as cleans, exhaust, vapours and gasses. These substances at last are blended in the earth and causes health hazards. Objective To determine concentration of fluoride in soils and vegetables grown in the vicinity of Zinc Smelter, Debari, Udaipur, Rajasthan. Materials and Methods Samples of vegetables and soil were collected from areas situated at 0, 1, 2, 5, and 10 km distance from the zinc smelter, Debari. Three samples of vegetables (i.e. Cabbage, Onion and Tomato) and 3 samples of soil {one sample from the upper layer of soil (i.e. 0 to 20 cm) and one from the deep layer (i.e. 20 – 40 cm)} at each distance were collected. The soil and vegetable samples were sealed in clean polythene bags and transported to the laboratory for analysis. One sample each of water and fertilizer from each distance were also collected. Results The mean fluoride concentration in the vegetables grown varied between 0.36 ± 0.69 to 0.71 ± 0.90 ppm. The fluoride concentration in fertilizer and water sample from various distances was found to be in the range of 1.4 – 1.5 ppm and 1.8 – 1.9 ppm respectively. Conclusion The fluoride content of soil and vegetables was found to be higher in places near to the zinc smelter. PMID:26557620

  12. Toxicity Assessment of Buprofezin, Lufenuron, and Triflumuron to the Earthworm Aporrectodea caliginosa

    Directory of Open Access Journals (Sweden)

    Mohamed E. I. Badawy

    2013-01-01

    Full Text Available Earthworms are particularly important soil macroinvertebrates and are often used in assessing the general impact of pesticide pollution in soil. The present study was conducted in order to investigate the toxicity of three insect growth regulators (IGRs buprofezin, lufenuron, and triflumuron, at different application rates and exposure times toward mature earthworms Aporrectodea caliginosa. The effects of these pesticides on the growth rate in relation to the activities of acetylcholinesterase (AChE and glutathione S-transferase (GST as biochemical indicators were evaluated to elucidate the mechanisms of action. Toxicity studies indicated that lufenuron was the most harmful pesticide to mature earthworms, followed in descending order by buprofezin and triflumuron. A reduction in growth rate in all pesticide-treated worms was dose-dependent over the 28-day exposure period, which was accompanied by a decrease in AChE and GST activities. Relationships between growth rate, AChE, and GST provided strong evidence for the involvement of pesticidal contamination in the biochemical changes in earthworms, which can be used as a bioindicator of soil contamination by pesticides.

  13. Development of a bioassay to assess the toxicity of oil sands sediments to pike (Esox lucius)

    Energy Technology Data Exchange (ETDEWEB)

    Turcotte, D.; Yuan, H.; Tumber, V.; Parrott, J. [Environment Canada, Ottawa, ON (Canada); Raine, J. [Saskatchewan Univ., Saskatoon, SK (Canada)

    2010-07-01

    Pike (Esox lucius) are a commercially sought fish species that inhabit the Athabasca River, which flows through the Athabasca oil sands. The fish are exposed to natural sources of bitumen from the McMurray formation. This study was conducted to design and implement a daily-renewal bioassay to assess the toxicity of oil sands to this fish species and to obtain information regarding the development of pike exposed to bitumen. Eggs were collected and fertilized with milt from spawning wild pike captured from Lake Diefenbaker in Saskatchewan. The fertilized eggs were exposed to different concentrations of sediments or culture water only (negative controls) until complete yolk absorption of control fish, approximately 15 days post-hatch. For the rest of the experiment, brine shrimp were fed to the walleye embryos every day after hatching. The developing fish were examined for morphological deformities, survival, hatching success, and changes in weight and length. The research findings indicated that pike is less sensitive than walleye and fathead minnow to the toxicity of oil sands sediments.

  14. In vivo monitoring of toxic metals: assessment of neutron activation and x-ray fluorescence techniques

    International Nuclear Information System (INIS)

    To date, cadmium, lead, aluminum, and mercury have been measured in vivo in humans. The possibilities of monitoring other toxic metals have also been demonstrated, but no human studies have been performed. Neutron activation analysis appears to be most suitable for Cd and Al measurements, while x-ray fluorescence is ideally suited for measurement of lead in superficial bone. Filtered neutron beams and polarized x-ray sources are being developed which will improve in vivo detection limits. Even so, several of the current facilities are already suitable for use in epidemiological studies of selected populations with suspected long-term low-level ''environmental'' exposures. Evaluation and diagnosis of patients presenting with general clinical symptoms attributable to possible toxic metal exposure may be assisted by in vivo examination. Continued in vivo monitoring of industrial workers, especially follow-up measurements, will provide the first direct assessment of changes in body burden and a direct measure of the biological life-times of these metals in humans. 50 refs., 4 figs., 2 tabs

  15. Toxicity assessment of tannery effluent treated by an optimized photo-Fenton process.

    Science.gov (United States)

    Borba, Fernando Henrique; Módenes, Aparecido Nivaldo; Espinoza-Quiñones, Fernando Rodolfo; Manenti, Diego Ricieri; Bergamasco, Rosangela; Mora, Nora Diaz

    2013-01-01

    In this work, an optimized photo-Fenton process was applied to remove pollutants from tannery industrial effluent (TIE) with its final toxicity level being assessed by a lettuce-seed-based bioassay test. A full 33 factorial design was applied for the optimization of long-term photo-Fenton experiments. The oPtimum conditions of the photo-Fenton process were attained at concentration values of 0.3 g Fe(2+) L(-1) and 20 g H2O2 L(-1) and pH3, for 120 min UV irradiation time. Reactor operating parameter (ROP) effects on the removal of chemical oxygen demand, colour, turbidity, total suspended solids and total volatile solids were evaluated, suggesting that a broad range of ROP values are also suitable to give results very near to those of the photo-Fenton experiments under optimal conditions. Based on the low calculated median lethal dose (LD50) values from a lettuce-seed-based bioassay test, we suggest that recalcitrant substances are present in treated TIE samples. A possible cause of the high toxicity level could partly be attributed to the nitrate concentration, which was not completely abated by the photo-Fenton process. Apart from this, the photo-Fenton process can be used as a part of an industrial effluent treatment system in order to abate high organic pollutant loads. PMID:23837315

  16. Algal photosynthetic responses to toxic metals and herbicides assessed by chlorophyll a fluorescence.

    Science.gov (United States)

    Kumar, K Suresh; Dahms, Hans-Uwe; Lee, Jae-Seong; Kim, Hyung Chul; Lee, Won Chan; Shin, Kyung-Hoon

    2014-06-01

    Chlorophyll a fluorescence is established as a rapid, non-intrusive technique to monitor photosynthetic performance of plants and algae, as well as to analyze their protective responses. Apart from its utility in determining the physiological status of photosynthesizers in the natural environment, chlorophyll a fluorescence-based methods are applied in ecophysiological and toxicological studies to examine the effect of environmental changes and pollutants on plants and algae (microalgae and seaweeds). Pollutants or environmental changes cause alteration of the photosynthetic capacity which could be evaluated by fluorescence kinetics. Hence, evaluating key fluorescence parameters and assessing photosynthetic performances would provide an insight regarding the probable causes of changes in photosynthetic performances. This technique quintessentially provides non-invasive determination of changes in the photosynthetic apparatus prior to the appearance of visible damage. It is reliable, economically feasible, time-saving, highly sensitive, versatile, accurate, non-invasive and portable; thereby comprising an excellent alternative for detecting pollution. The present review demonstrates the applicability of chlorophyll a fluorescence in determining photochemical responses of algae exposed to environmental toxicants (such as toxic metals and herbicides).

  17. Development of a bioassay to assess the toxicity of oil sands sediments to pike (Esox lucius)

    International Nuclear Information System (INIS)

    Pike (Esox lucius) are a commercially sought fish species that inhabit the Athabasca River, which flows through the Athabasca oil sands. The fish are exposed to natural sources of bitumen from the McMurray formation. This study was conducted to design and implement a daily-renewal bioassay to assess the toxicity of oil sands to this fish species and to obtain information regarding the development of pike exposed to bitumen. Eggs were collected and fertilized with milt from spawning wild pike captured from Lake Diefenbaker in Saskatchewan. The fertilized eggs were exposed to different concentrations of sediments or culture water only (negative controls) until complete yolk absorption of control fish, approximately 15 days post-hatch. For the rest of the experiment, brine shrimp were fed to the walleye embryos every day after hatching. The developing fish were examined for morphological deformities, survival, hatching success, and changes in weight and length. The research findings indicated that pike is less sensitive than walleye and fathead minnow to the toxicity of oil sands sediments.

  18. Assessment of Pen Branch delta and corridor vegetation changes using multispectral scanner data 1992--1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-01-01

    Airborne multispectral scanner data were used to monitor natural succession of wetland vegetation species over a three-year period from 1992 through 1994 for Pen Branch on the Savannah River Site in South Carolina. Image processing techniques were used to identify and measure wetland vegetation communities in the lower portion of the Pen Branch corridor and delta. The study provided a reliable means for monitoring medium- and large-scale changes in a diverse environment. Findings from the study will be used to support decisions regarding remediation efforts following the cessation of cooling water discharge from K reactor at the Department of Energy`s Savannah River Site in South Carolina.

  19. Pharmacophore modeling and in silico toxicity assessment of potential anticancer agents from African medicinal plants

    Directory of Open Access Journals (Sweden)

    Ntie-Kang F

    2016-07-01

    Full Text Available Fidele Ntie-Kang,1,2,* Conrad Veranso Simoben,1,2,* Berin Karaman,1 Valery Fuh Ngwa,3 Philip Neville Judson,4 Wolfgang Sippl,1 Luc Meva’a Mbaze5 1Department of Pharmaceutical Chemistry, Martin-Luther University of Halle-Wittenberg, Halle (Saale, Germany; 2Department of Chemistry, University of Buea, Buea, Cameroon; 3Interuniversity Institute For Biostatistics and Statistical Bioinformatics (I-BioStat, University of Hasselt, Hasselt, Belgium; 4Chemical Bioactivity Information Centre, Harrogate, UK; 5Department of Chemistry, Faculty of Science, University of Douala, Douala, Cameroon *These authors contributed equally to this work Abstract: Molecular modeling has been employed in the search for lead compounds of chemotherapy to fight cancer. In this study, pharmacophore models have been generated and validated for use in virtual screening protocols for eight known anticancer drug targets, including tyrosine kinase, protein kinase B β, cyclin-dependent kinase, protein farnesyltransferase, human protein kinase, glycogen synthase kinase, and indoleamine 2,3-dioxygenase 1. Pharmacophore models were validated through receiver operating characteristic and Güner–Henry scoring methods, indicating that several of the models generated could be useful for the identification of potential anticancer agents from natural product databases. The validated pharmacophore models were used as three-dimensional search queries for virtual screening of the newly developed AfroCancer database (~400 compounds from African medicinal plants, along with the Naturally Occurring Plant-based Anticancer Compound-Activity-Target dataset (comprising ~1,500 published naturally occurring plant-based compounds from around the world. Additionally, an in silico assessment of toxicity of the two datasets was carried out by the use of 88 toxicity end points predicted by the Lhasa’s expert knowledge-based system (Derek, showing that only an insignificant proportion of the promising

  20. Toxicity assessment of TiO{sub 2} nanoparticles in zebrafish embryos under different exposure conditions

    Energy Technology Data Exchange (ETDEWEB)

    Clemente, Z., E-mail: zairaclemente@yahoo.com.br [Laboratório de Ecotoxicologia e Biossegurança, Embrapa CNPMA, Jaguariúna, SP (Brazil); Programa de Pós-graduação em Biologia Funcional e Molecular, UNICAMP, Campinas, SP (Brazil); Castro, V.L.S.S. [Laboratório de Ecotoxicologia e Biossegurança, Embrapa CNPMA, Jaguariúna, SP (Brazil); Moura, M.A.M. [Laboratório da Ciência das Plantas Daninhas, Instituto Biológico, APTA/SAA, Campinas, SP (Brazil); Jonsson, C.M. [Laboratório de Ecotoxicologia e Biossegurança, Embrapa CNPMA, Jaguariúna, SP (Brazil); Fraceto, L.F. [Programa de Pós-graduação em Biologia Funcional e Molecular, UNICAMP, Campinas, SP (Brazil); Departamento de Engenharia Ambiental, UNESP, Sorocaba, SP (Brazil)

    2014-02-15

    factors involved in the toxicity of these nanoparticles, as well as to the establishment of protocols for risk assessments of nanotechnology.

  1. Growing knowledge of using embryonic stem cells as a novel tool in developmental risk assessment of environmental toxicants.

    Science.gov (United States)

    Rezvanfar, Mohammad Amin; Hodjat, Mahshid; Abdollahi, Mohammad

    2016-08-01

    Developmental toxicology is an important area of novel toxicology. In recent years, there have been big concerns toward the increasing exposure to pharmaceutical agents, food additives, pesticides, occupational toxicants, and environmental pollutants, as well as their possible association with all aspects of male or female-mediated transient or permanent defects in progeny. Therefore, it is of great importance to look for new predictive models to evaluate environmental toxicants before they can harm the human health and embryo development. In this regard, new cell-based in vitro screening models have been developed and validated in predictive toxicology to minimize assay costs and animal usage. Stem cell-based models have been increasingly applied for predicting the toxicity of chemicals. One of the most promising existing in vitro developmental toxicity tests is the validated embryonic stem cell test (EST) which employs marine or human embryonic stem cells to assess the potential of chemicals embryotoxicity. These cells are very suitable for embryotoxicity assessment as they have been demonstrated to specify cellular developmental processes during early embryogenesis and gene expression patterns of differentiation to functionally competent specialized cell types. The present paper aimed at criticizing the human and experimental evidence for developmental toxic effects of environmental toxicants based on ESCs models. Accordingly, pesticides, heavy metals, plasticizers, nanomaterials and some solvents have been considered as the main evaluated environmental toxicants inducing developmental toxicity. At the end, current challenges, pros and cons of using ESCs as an alternative validated in vitro model for specific developmental toxicity screening are discussed. PMID:27208651

  2. A new index to assess chemicals increasing the greenhouse effect based on their toxicity to algae.

    Science.gov (United States)

    Wang, Ting; Zhang, Xiaoxian; Tian, Dayong; Gao, Ya; Lin, Zhifen; Liu, Ying; Kong, Lingyun

    2015-11-01

    CO2, as the typical greenhouse gas causing the greenhouse effect, is a major global environmental problem and has attracted increasing attention from governments. Using algae to eliminate CO2, which has been proposed as an effective way to reduce the greenhouse effect in the past decades, can be disturbed by a growing number of artificial chemicals. Thus, seven types of chemicals and Selenastrum capricornutum (algae) were examined in this study, and the good consistency between the toxicity of artificial chemicals to algae and the disturbance of carbon fixation by the chemicals was revealed. This consistency showed that the disturbance of an increasing number of artificial chemicals to the carbon fixation of algae might be a "malware" worsening the global greenhouse effect. Therefore, this study proposes an original, promising index to assess the risk of deepening the greenhouse effect by artificial chemicals before they are produced and marketed.

  3. In vivo assessment of the toxic potential of Dissotis rotundifolia whole plant extract in Sprague-Dawley rats

    Institute of Scientific and Technical Information of China (English)

    Charles Ansah; Michael Buenor Adinortey; Jerry Asiedu-Larbi; Benjamin Aboagye; Du-Bois Asante; Alexander Kwadwo Nyarko

    2016-01-01

    Objective: To assess the toxic potential of Dissotis rotundifolia (D. rotundifolia) whole plant extract in Spraque–Dawley rats within a 2-week period of administration. Methods: Methanolic extract of D. rotundifolia was administered orally once daily at dose levels of 0, 100, 300 and 1 000 mg/kg body weight for 14 days. Toxicity was assessed using mortality, clinical signs, body and organ weights, hematological indices, serum chemistry parameters and histopathological analyses. Results: There were no treatment-related mortalities or differences in clinical signs, hematology and serum biochemistry. This was confirmed by micrographs obtained from histopathological analysis. Conclusions: The results obtained from the sub-acute toxicological assessment of D. rotundifolia extract suggest that the extract is non-toxic at doses up to 1 000 mg/kg/day administered for a period of 14 days.

  4. Assessment of the toxicity of a substance under Canadian environmental protection act, a case study. Polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Nadon, B.; Germain, A.; Coillie, R. van [Environment Canada, Montreal (Canada)

    1995-12-31

    The Canadian Environmental Protection Act (CEPA) proclaimed in 1988 requires the Canadian Ministers of the Environment and of National Health and Welfare to assess the toxicity of different substances. A Priority Substances List containing 44 substances was developed and their assessments had to determine if they were `toxic`, according to the CEPA definition. This definition states that `a substance is toxic if it is entering or may enter the environment in a quantity or concentration or under conditions (a) having or that may have an immediate or long-term harmful effect on the environment, (b) constituting or that may constitute a danger to the environment on which human life depends; or (c) constituting or that may constitute a danger in Canada to human life of health.` This presentation use the assessment of the polycyclic aromatic hydrocarbons (PAHs) as an example of this procedure. (author)

  5. Spectral mixture analysis to assess post-fire vegetation regeneration using Landsat Thematic Mapper imagery: Accounting for soil brightness variation

    Science.gov (United States)

    Veraverbeke, S.; Somers, B.; Gitas, I.; Katagis, T.; Polychronaki, A.; Goossens, R.

    2012-02-01

    Post-fire vegetation cover is a crucial parameter in rangeland management. This study aims to assess the post-fire vegetation recovery 3 years after the large 2007 Peloponnese (Greece) wildfires. Post-fire recovery landscapes typically are mixed vegetation-substrate environments which makes spectral mixture analysis (SMA) a very effective tool to derive fractional vegetation cover maps. Using a combination of field and simulation techniques this study aimed to account for the impact of background brightness variability on SMA model performance. The field data consisted out of a spectral library of in situ measured reflectance signals of vegetation and substrate and 78 line transect plots. In addition, a Landsat Thematic Mapper (TM) scene was employed in the study. A simple SMA, in which each constituting terrain feature is represented by its mean spectral signature, a multiple endmember SMA (MESMA) and a segmented SMA, which accounts for soil brightness variations by forcing the substrate endmember choice based on ancillary data (lithological map), were applied. In the study area two main spectrally different lithological units were present: relatively bright limestone and relatively dark flysch (sand-siltstone). Although the simple SMA model resulted in reasonable regression fits for the flysch and limestones subsets separately (coefficient of determination R2 of respectively 0.67 and 0.72 between field and TM data), the performance of the regression model on the pooled dataset was considerably weaker ( R2 = 0.65). Moreover, the regression lines significantly diverged among the different subsets leading to systematic over-or underestimations of the vegetative fraction depending on the substrate type. MESMA did not solve the endmember variability issue. The MESMA model did not manage to select the proper substrate spectrum on a reliable basis due to the lack of shape differences between the flysch and limestone spectra,. The segmented SMA model which accounts for

  6. Risk assessment of drug interaction potential and concomitant dosing pattern on targeted toxicities in pediatric cancer patients.

    Science.gov (United States)

    Barrett, Jeffrey S; Patel, Dimple; Dombrowsky, Erin; Bajaj, Gaurav; Skolnik, Jeffrey M

    2013-07-01

    This investigation evaluated the impact of potential drug interactions on the incidence of reported toxicities seen with common dosing patterns in children with cancer, with the intent of being able to screen and reduce the incidence of adverse drug reactions (ADRs) in the future. Toxicity reported in pediatric cancer patients treated at the Children's Hospital of Philadelphia from 2004 to 2010 were abstracted from a cancer tumor registry and merged with drug order profiles from the medical record system. Analysis datasets were created in SAS and permutation algorithms were used to identify pairwise drug combinations associated with specific toxicity occurrence. Relative risk of toxicity based on dosing pattern was assessed via comparison to control patients. A total of 326 of 1,713 patients (19%) had reportable toxicities. Neutrophil count decreases and alanine aminotransferase increases represented the highest occurring, corresponding to 28.8% and 31.9% prevalence among patients reporting toxicity, respectively. Of coadministered drug pairs, acetaminophen-diphenhydramine occurred most frequently; however, methotrexate-vincristine was the highest occurring pair linked to a single toxicity (hepatotoxicity). Toxicity was highly associated with the diagnoses of leukemia (52.1%) or neuroblastoma (28.5%). Comparison of the dosing interval (≤30 versus >30 min) suggested that risk of toxicity can be associated with the timing of coadministration, with ≤30 min increasing the risk of hepatotoxicity with fentanyl-midazolam and methotrexate-midazolam combinations. Knowledge of drug interactions in children with cancer may help reduce the incidence of ADRs by providing pharmacotherapy options that may reduce the likelihood of toxicity. PMID:23595361

  7. Life cycle toxicity assessment of pesticides used in integrated and organic production of oranges in the Comunidad Valenciana, Spain.

    Science.gov (United States)

    Juraske, Ronnie; Sanjuán, Neus

    2011-02-01

    The relative impacts of 25 pesticides including acaricides, fungicides, herbicides, insecticides, and post-harvest fungicides, used in the production of oranges in Spain were assessed with current life cycle impact assessment (LCIA) tools. Chemical specific concentrations were combined with pesticide emission data and information on chemical toxicity to assess human toxicity and freshwater ecotoxicity impacts. As a case study, the relative impacts of two orange production systems in the region of Valencia, integrated pest management (IP) and organic production (OP), were assessed. The evaluation of active ingredients showed that on average acaricides have the highest human toxicity impact scores, while for freshwater ecotoxicity insecticides show the highest impact. In both impact categories the lowest impact scores were calculated for herbicides. In the production of 1 kg of orange fruits, where several kinds of pesticides are combined, results show that post-harvest fungicides can contribute more than 95% to the aggregate human toxicity impacts. More than 85% of aquatic ecotoxicity is generated by fungicides applied before harvest. The potential to reduce impacts on freshwater ecosystems is seven orders of magnitude, while impacts on human health can be reduced by two orders of magnitude. Hence, this stresses the importance of a careful pre-selection of active ingredients. In both impact categories, organic production represents the least toxic pest-control method.

  8. [Distribution and Risk Assessment of Sulfonamides Antibiotics in Soil and Vegetables from Feedlot Livestock].

    Science.gov (United States)

    Jin, Cai-xia; Si, Xiao-wei; Wang, Zi-ying; Zhang, Qin-wen

    2016-04-15

    Soil and vegetable samples were collected from 13 different livestock farms of different sizes in Xinxiang of China, and the residues of three sulfonamides including sulfadiazine, sulfamonomethoxine, and sulfamethoxazole were analyzed by HPLC with a fluorimetric detector, The results indicated that the total concentration ranges of the three sulfonamides in soil and vegetable were 7.60-176.26 µg · kg⁻¹ and ND-32, 70 µg · kg⁻¹, respectively. The mean concentrations were 70.73 µg · kg⁻¹ and 7.08 µg · kg⁻¹ for soil and vegetables. The residue levels in soil were all lower than the ecotoxic effect trigger value (100 µg · kg⁻¹) set by the Veterinary Medicine International Coordination Commission, indicating the low risk for organisms in soil. The concentrations of three sulfonamides varied significantly in different kinds of vegetables and were all lower than the acceptable daily intake values [50 µg · (kg ·d)⁻¹] set by Joint FAO/WHO Expert CommIttee on Food Additives. But we cannot neglect the potential ecotoxicity and resistance for human via food chain. PMID:27548983

  9. A quantitative assessment of the vegetation types on the island of St. Eustatius, Dutch Caribbean

    Directory of Open Access Journals (Sweden)

    Tinde van Andel

    2016-07-01

    Full Text Available Caribbean dry forests are among the most endangered tropical ecosystems on earth. Several studies exist on their floristic composition and their recovery after natural or man-made disturbances, but little is known on the small Dutch Caribbean islands. In this study, we present quantitative data on plant species richness and abundance on St. Eustatius, one of the smallest islands of the Lesser Antilles. We collected and identified trees, shrubs, lianas and herbs in 11 plots of 25 x 25 m in different vegetation types. We compared their floristic composition and structure to vegetation surveys from roughly the same locations in the 1990s and 1950s. We found substantial differences among our 11 plots: vegetation types varied from evergreen forests to deciduous shrubland and open woodland. The number of tree species ≥10 cm DBH ranged between one and 17, and their density between three and 82 per plot. In spite that all plots were subject to grazing by free roaming cattle, canopy height and floristic diversity have increased in the last decades. Invasive species are present in the open vegetation types, but not under (partly closed canopy. Comparison with the earlier surveys showed that the decline of agriculture and conservation efforts resulted in the regeneration of dry forests between the 1950s and 2015. This process has also been reported from nearby islands and offers good opportunities for the future conservation of Caribbean dry forests.

  10. Environmental behavior of technetium in soil and vegetation: implications for radiological impact assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, F.O.

    1982-04-01

    Significant radiological exposures have been estimated for hypothetical atmospheric releases of Tc-99 from gaseous diffusion facilities when vegetation-to-soil concentration ratios representative of laboratory experiments are substituted for generic default values assumed in current regulatory models. To test the relevancy of these laboratory ratios, field investigations were conducted to obtain measurements of the vegetation-to-soil concentration ratio for Tc-99 in samples collected near operating gaseous diffusion facilities and to observe the dynamic behavior of technetium in soil and vegetation following a single application of a sprayed solution of /sup 95m/TcO/sub 4//sup -/ Comparison of observed field concentration ratios and calculated steady-state concentration ratios with ratios obtained from previous laboratory experiments indicates that concentration ratios obtained from field data are one to two orders of magnitude less than those obtained from the laboratory. Furthermore, a substantial accumulation of technetium in soil and vegetation may not occur over long periods of time, since concentrations of technetium in both environmental media were observed to decrease with time subsequent to initial application of /sup 95m/TcO/sub 4//sup -/.

  11. Environmental behavior of technetium in soil and vegetation: implications for radiological impact assessment

    International Nuclear Information System (INIS)

    Significant radiological exposures have been estimated for hypothetical atmospheric releases of Tc-99 from gaseous diffusion facilities when vegetation-to-soil concentration ratios representative of laboratory experiments are substituted for generic default values assumed in current regulatory models. To test the relevancy of these laboratory ratios, field investigations were conducted to obtain measurements of the vegetation-to-soil concentration ratio for Tc-99 in samples collected near operating gaseous diffusion facilities and to observe the dynamic behavior of technetium in soil and vegetation following a single application of a sprayed solution of /sup 95m/TcO4- Comparison of observed field concentration ratios and calculated steady-state concentration ratios with ratios obtained from previous laboratory experiments indicates that concentration ratios obtained from field data are one to two orders of magnitude less than those obtained from the laboratory. Furthermore, a substantial accumulation of technetium in soil and vegetation may not occur over long periods of time, since concentrations of technetium in both environmental media were observed to decrease with time subsequent to initial application of /sup 95m/TcO4-

  12. Assessing intra-annual vegetation regrowth after fire using the pixel based regeneration index

    NARCIS (Netherlands)

    Lhermitte, S.; Verbesselt, J.; Verstraeten, W.W.; Veraverbeke, S.; Coppin, P.

    2011-01-01

    Several remote sensing studies have discussed the potential of satellite imagery as an alternative for extensive field sampling to quantify fire-vegetation impact over large areas. Most studies depend on Landsat image availability with infrequent image acquisition dates and consequently are limited

  13. Reverse osmosis pretreatment method for toxicity assessment of domestic wastewater using Vibrio qinghaiensis sp.-Q67.

    Science.gov (United States)

    Ma, Xiaoyan Y; Wang, Xiaochang C; Hao Ngo, Huu; Guo, Wenshan; Wu, Maoni N; Wang, Na

    2013-11-01

    Luminescent bacterial test is a fast and sensitive method for acute toxicity assessment of water and wastewater. In this study, an improved toxicity testing method was developed using the freshwater luminescent bacteria Vibrio qinghaiensis sp.-Q67 that involved pretreatment of water samples with reverse osmosis (RO) to eliminate the interferences caused by nutrients in concentrated samples and to improve the reliability and sensitivity of the analysis. Because water samples contain low concentrations of several target toxic substances, rapid acute toxicity testing method that is commonly employed does not achieve enough sensitivity. The proposed RO pretreatment could effectively enrich organic and inorganic substances in water samples to enable a more effective and sensitive toxicity evaluation. The kinetic characteristics of toxicity of raw sewage and secondary effluent were evaluated based on the relative luminescence unit (RLU) curves and time-concentration-effect surfaces. It was observed that when the exposure time was prolonged to 8-h or longer, the bacteria reached the logarithmic growth stage. Hence, the stimulating effects of the coexisting ions (such as Na(+), K(+), NO3(-)) in the concentrated samples could be well eliminated. A 10-h exposure time in proposed Q67 test was found to quantitatively evaluate the toxicity of the organic and inorganic pollutants in the RO-concentrated samples. PMID:23988093

  14. Palaeo plant diversity in subtropical Africa – ecological assessment of a conceptual model of climate–vegetation interaction

    Directory of Open Access Journals (Sweden)

    V. P. Groner

    2015-07-01

    Full Text Available We here critically re-assess a conceptual model dealing with the potential effect of plant diversity on climate–vegetation feedback, and provide an improved version adjusted to plant types that prevailed during the African Humid Period (AHP. Our work contributes to the understanding of the timing and abruptness of vegetation decline at the end of the AHP, investigated by various working groups during the past two decades using a wide range of model and palaeoproxy reconstruction approaches. While some studies indicated an abrupt collapse of vegetation at the end of the AHP, others suggested a gradual decline. Claussen et al. (2013 introduced a new aspect in the discussion, proposing that plant diversity in terms of moisture requirements could affect the strength of climate–vegetation feedback. In a conceptual model study, the authors illustrated that high plant diversity could stabilize an ecosystem, whereas a reduction in plant diversity might allow for an abrupt regime shift under gradually changing environmental conditions. Based on recently published pollen data and the current state of ecological literature, we evaluate the representation of climate–vegetation feedback in this conceptual approach, and put the suggested conclusions into an ecological context. In principle, the original model reproduces the main features of different plant types interacting together with climate although vegetation determinants other than precipitation are neglected. However, the model cannot capture the diversity of AHP vegetation. Especially tropical gallery forest taxa, indirectly linked to local precipitation, are not appropriately represented. In order to fill the gaps in the description of plant types regarding AHP diversity, we modify the original model in four main aspects. First, the growth ranges in terms of moisture requirements are extended by upper limits to represent full environmental envelopes. Second, data-based AHP plant types replace

  15. A tiered approach for the human health risk assessment for consumption of vegetables from with cadmium-contaminated land in urban areas

    International Nuclear Information System (INIS)

    Consumption of vegetables that are grown in urban areas takes place worldwide. In developing countries, vegetables are traditionally grown in urban areas for cheap food supply. In developing and developed countries, urban gardening is gaining momentum. A problem that arises with urban gardening is the presence of contaminants in soil, which can be taken up by vegetables. In this study, a scientifically-based and practical procedure has been developed for assessing the human health risks from the consumption of vegetables from cadmium-contaminated land. Starting from a contaminated site, the procedure follows a tiered approach which is laid out as follows. In Tier 0, the plausibility of growing vegetables is investigated. In Tier 1 soil concentrations are compared with the human health-based Critical soil concentration. Tier 2 offers the possibility for a detailed site-specific human health risk assessment in which calculated exposure is compared to the toxicological reference dose. In Tier 3, vegetable concentrations are measured and tested following a standardized measurement protocol. To underpin the derivation of the Critical soil concentrations and to develop a tool for site-specific assessment the determination of the representative concentration in vegetables has been evaluated for a range of vegetables. The core of the procedure is based on Freundlich-type plant–soil relations, with the total soil concentration and the soil properties as variables. When a significant plant–soil relation is lacking for a specific vegetable a geometric mean of BioConcentrationFactors (BCF) is used, which is normalized according to soil properties. Subsequently, a ‘conservative’ vegetable-group-consumption-rate-weighted BioConcentrationFactor is calculated as basis for the Critical soil concentration (Tier 1). The tool to perform site-specific human health risk assessment (Tier 2) includes the calculation of a ‘realistic worst case’ site-specific vegetable

  16. A tiered approach for the human health risk assessment for consumption of vegetables from with cadmium-contaminated land in urban areas

    Energy Technology Data Exchange (ETDEWEB)

    Swartjes, Frank A., E-mail: frank.swartjes@rivm.nl; Versluijs, Kees W.; Otte, Piet F.

    2013-10-15

    Consumption of vegetables that are grown in urban areas takes place worldwide. In developing countries, vegetables are traditionally grown in urban areas for cheap food supply. In developing and developed countries, urban gardening is gaining momentum. A problem that arises with urban gardening is the presence of contaminants in soil, which can be taken up by vegetables. In this study, a scientifically-based and practical procedure has been developed for assessing the human health risks from the consumption of vegetables from cadmium-contaminated land. Starting from a contaminated site, the procedure follows a tiered approach which is laid out as follows. In Tier 0, the plausibility of growing vegetables is investigated. In Tier 1 soil concentrations are compared with the human health-based Critical soil concentration. Tier 2 offers the possibility for a detailed site-specific human health risk assessment in which calculated exposure is compared to the toxicological reference dose. In Tier 3, vegetable concentrations are measured and tested following a standardized measurement protocol. To underpin the derivation of the Critical soil concentrations and to develop a tool for site-specific assessment the determination of the representative concentration in vegetables has been evaluated for a range of vegetables. The core of the procedure is based on Freundlich-type plant–soil relations, with the total soil concentration and the soil properties as variables. When a significant plant–soil relation is lacking for a specific vegetable a geometric mean of BioConcentrationFactors (BCF) is used, which is normalized according to soil properties. Subsequently, a ‘conservative’ vegetable-group-consumption-rate-weighted BioConcentrationFactor is calculated as basis for the Critical soil concentration (Tier 1). The tool to perform site-specific human health risk assessment (Tier 2) includes the calculation of a ‘realistic worst case’ site-specific vegetable

  17. Exploration on risk assessment of pesticide residues in vegetables%蔬菜农药残留风险评估探讨

    Institute of Scientific and Technical Information of China (English)

    黄和勇

    2012-01-01

    Based on the analysis on standard-exceeded reason of pesticide residues in vegetables,this paper elaborated the process of risk assessment of pesticide residues in vegetables,explored the countermeasures to strengthen the task in risk assessment of pesticide residues in vegetables.%分析蔬菜农药残留超标的原因,阐述蔬菜农药残留风险评估的过程,探讨加强蔬菜农药残留风险评估工作的对策。

  18. Rapid soil toxicity assessment at Rum Jungle, Northern Territory - a requirement for rehabilitation design, quality control and monitoring

    International Nuclear Information System (INIS)

    The rehabilitation of degraded land at the old Rum Jungle mine site was largely designed and constructed over a three year period from November, 1982 to December, 1985 under a strict schedule of time and budget constraints. Reliable information on the potential toxicity of affected soil or spoil to plant growth could not be gathered by pot or field trials due to time constraints but was still required to develop cost effective and successful rehabilitation options. Detailed chemical analyses of heavy metals, cations and anions were to costly and time-consuming to form a regular part of a routine toxicity assessment program. Therefore the detailed chemical data from earlier investigations were related to the general parameters of pH, electrical conductivity and lime requirement to assess the degree of soil toxicity. These rapidly determined parameters were found to be reproducible and representative indications of soil conditions. The rapid soil toxicity assessment was a sufficient source of information to develop options for soil or spoil removal, depth or type of soil cover or amount of lime treatment to overcome soil toxicity and allow successful revegetation

  19. Investigation of a Patient Reported Outcome tool to assess radiotherapy-related toxicity prospectively in patients with lung cancer

    International Nuclear Information System (INIS)

    Background and purpose: There is a paucity of data regarding the feasibility and relevance of Patient Reported Outcome (PRO) tools to assess radiotherapy-related toxicity in lung cancer. Material and methods: From January to June 2013, lung cancer patients undergoing thoracic radiotherapy/chemo-radiotherapy completed nine patient-adapted Common Terminology Criteria for Adverse Events (CTCAE), the European Organisation for Research and Treatment of Cancer Quality of Life (QoL) questionnaire and the Hospital Anxiety and Depression Scale (HADS) at baseline, the end of radiotherapy and at follow-up. Clinicians completed the same CTCAE items and agreement between patients’ and clinicians’ reporting was assessed using weighted kappa coefficients. QoL and HADS scores were correlated with the patients’ and clinicians’ reported toxicity. Results: 70/116 patients completed the questionnaires for at least one time point excluding baseline. Agreement between patients’ and clinicians’ reported toxicity ranged from slight to substantial. Most discrepancies were within one grade and patients reported greater severity than clinicians for most symptoms. QoL and HADS scores were more strongly correlated with the patients’ compared to clinicians’ matching toxicity reports. The PRO tool was found to be statistically reliable. Conclusions: The use of a PRO tool in lung cancer radiotherapy is feasible, reliable and acceptable to patients. PROs should be integrated in future clinical trials evaluating new radiotherapy approaches to assess toxicity

  20. Indium arsenide as a material for biological applications: Assessment of surface modifications, toxicity, and biocompatibility

    Science.gov (United States)

    Jewett, Scott A.

    III-V semiconductors such as InAs have recently been employed in a variety of applications where the electronic and optical characteristics of traditional, silicon-based materials are inadequate. InAs has a narrow band gap and very high electron mobility in the near-surface region, which makes it very attractive for high performance transistors, optical applications, and chemical sensing. However, InAs forms an unstable surface oxide layer in ambient conditions, which can corrode over time and leach toxic indium and arsenic components. Current research has gone into making InAs more attractive for biological applications through passivation of the surface by adlayer adsorption. In particular, wet-chemical methods are current routes of exploration due to their simplicity, low cost, and flexibility in the type of passivating molecule. This dissertation focuses on surface modifications of InAs using wet-chemical methods in order to further its use in biological applications. First, the adsorption of collagen binding peptides and mixed peptide/thiol adlayers onto InAs was assessed. X-ray photoelectron spectroscopy (XPS) along with atomic force microscopy (AFM) data suggested that the peptides successfully adsorbed onto InAs, but were only able to block oxide regrowth to a relatively low extent. This low passivation ability is due to the lack of covalent bonds of the peptide to InAs, which are necessary to effectively block oxide regrowth. The addition of a thiol, in the form of mixed peptide/thiol adlayers greatly enhanced passivation of InAs while maintaining peptide presence on the surface. Thiols form tight, covalent bonds with InAs, which prevents oxide regrowth. The presence of the collagen-binding peptide on the surface opens the door to subsequent modification with collagen or polyelectrolyte-based adlayers. Next, the stability and toxicity of modified InAs substrates were determined using inductively coupled plasma mass spectrometry (ICP-MS) and zebrafish

  1. Assessing in vivo toxicity of graphene materials: current methods and future outlook.

    Science.gov (United States)

    Ma, Yufei; Shen, He; Tu, Xiaolong; Zhang, Zhijun

    2014-07-01

    Graphene, a novel 2D carbon nanomaterial with unique properties, has attracted massive attention. Evaluating its toxicity is of great significance due to its potential applications in many fields, especially in biomedicine. In this review, the toxicity of graphene-based nanomaterials (GNMs) and related mechanisms at the molecular and cellular level, various approaches to evaluation of the in vivo toxicity of GNMs and major factors defining their toxicity will be discussed and summarized. This review will allow better understanding of the in vitro and in vivo toxicity of GNMs, which, we believe, may facilitate design and fabrication of novel, biocompatible and efficient GNM-based systems for biomedical applications.

  2. Evaluating the relationship between plasma and skin carotenoids and reported dietary intake in elementary school children to assess fruit and vegetable intake

    Science.gov (United States)

    Accurate assessment of dietary intake of children can be challenging due to the limited reliability of current dietary assessment methods in children. While plasma carotenoid concentrations has been used to assess fruit and vegetable intake, this testing is rarely conducted in school settings in chi...

  3. Final environmental assessment for vegetation control at VHF stations, microwave stations, electrical substations, and pole yards

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-13

    Southwestern Power Adm. operates very high frequency (VHF) and microwave radio stations, electrical substations, and pole yards for electric power transmission throughout AR, MO, and OK. Vegetation growth at the stations must be suppressed for safety of operation and personnel. Southwestern has been using a combination of mechanical/manual and herbicide control for this purpose; Federally- mandated reductions in staff and budgetary resources require Southwestern to evaluate all potentially efficient methods for vegetation control. Three alternatives were examined: no action, mechanical/manual control, and (proposed) a combination of mechanical/manual and herbicide control. Environmental impacts on air and water quality, wetlands, wildlife, endangered species, archaeological and other resources, farmland, human health, transportation, etc. were evaluated.

  4. Assessing the vegetation canopy influences on wind flow using wind tunnel experiments with artificial plants

    Indian Academy of Sciences (India)

    Youngjoo Hong; Dongyeob Kim; Sangjun Im

    2016-04-01

    Wind erosion causes serious problems and considerable threat in most regions of the world. Vegetation on the ground has an important role in controlling wind erosion by covering soil surface and absorbingwind momentum. A set of wind tunnel experiments was performed to quantitatively examine the effect of canopy structure on wind movement. Artificial plastic vegetations with different porosity and canopyshape were introduced as the model canopy. Normalized roughness length $(Z0/H)$ and shear velocity ratio $(R)$ were analyzed as a function of roughness density ($\\lambda$). Experiments showed that $Z0/H$ increasesand R decreases as λ reaches a maximum value, $\\lambda_{max}$, while the values of $Z0/H$ and $R$ showed little change with $\\lambda$ value beyond as $\\lambda_{max}$.

  5. Assessing the vegetation canopy influences on wind flow using wind tunnel experiments with artificial plants

    Science.gov (United States)

    Hong, Youngjoo; Kim, Dongyeob; Im, Sangjun

    2016-04-01

    Wind erosion causes serious problems and considerable threat in most regions of the world. Vegetation on the ground has an important role in controlling wind erosion by covering soil surface and absorbing wind momentum. A set of wind tunnel experiments was performed to quantitatively examine the effect of canopy structure on wind movement. Artificial plastic vegetations with different porosity and canopy shape were introduced as the model canopy. Normalized roughness length ( Z 0/ H) and shear velocity ratio ( R) were analyzed as a function of roughness density ( λ). Experiments showed that Z 0/ H increases and R decreases as λ reaches a maximum value, λ max, while the values of Z 0/ H and R showed little change with λ value beyond as λ max.

  6. Assessing metal transfer to vegetation and grazers on reclaimed pyritic Zn and Pb tailings.

    Science.gov (United States)

    Callery, S; Courtney, R

    2015-12-01

    A study of the concentrations of zinc and lead in an engineered soil capping system overlying sulphide mine tailings was undertaken. Tailings geochemistry, soil cover and vegetation were monitored over a 4-year period, and a cattle grazing demonstration exercise was conducted over a 1-year period. Whilst the tailings had a relatively high pyrite content and demonstrated oxidation, a circum neutral pH was observed for the duration of the study period due to the high dolomitic content. No evidence of metal mobility into the soil cover and vegetation was observed over the monitoring period. Relatively high Zn herbage content is attributed to the glacial till component of the soil cover. Similarly, no evidence of metal transfer to grazing cattle was observed through blood and tissue analysis with Zn content not significantly different from control animals. Pb tissue content was below limit of detection. PMID:26282438

  7. Occurrence and potential combined toxicity of dissolved organic contaminants in the Forth estuary and Firth of Forth, Scotland assessed using passive samplers and an algal toxicity test.

    Science.gov (United States)

    Emelogu, Emmanuel S; Pollard, Pat; Dymond, Peter; Robinson, Craig D; Webster, Lynda; McKenzie, Craig; Dobson, Judy; Bresnan, Eileen; Moffat, Colin F

    2013-09-01

    As an alternative procedure to conventional water quality assessment, the presence and combined toxicity of dissolved organic contaminants in water at five sites in the Forth estuary and the Firth of Forth, Scotland, United Kingdom was investigated using silicone rubber passive sampling devices (SR-PSDs) and an algal growth inhibition bioassay. SR-PSDs were deployed in water at the five sites for ~2 months. Following retrieval, extracts from the deployed SR-PSDs were assessed for both algal growth inhibition and the occurrence of a wide range of organic contaminants, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and a variety of plant protection products (PPPs; commonly referred to collectively as 'pesticides'). The 72 h algal growth inhibition test was performed using a native marine phytoplankton (Diacronema lutheri) in 24 well microplates. Freely dissolved (e.g. bioavailable) concentrations of PAHs and PCBs were determined using performance reference compounds (PRCs). The algal toxicity tests exhibited varied effects at the five sites indicating the presence of, and exposure to, phytotoxic compounds and their potential toxicity in the Forth. The individual and total dissolved concentrations of 40 PAHs and 32 PCBs measured in the study were relatively low and showed input of petrogenic, atmospheric and sewage related sources. Several pesticides of diverse polarities were identified in the water suggesting sources from both riverine input and direct discharges. The study thus illustrates the value of combining bioassays and chemical analysis (with effective sampling technique) for a realistic and rapid assessment of organic contaminants in the aquatic environment. PMID:23728064

  8. Assessment of peripheral neuropathy in male hospitalized patients with lead toxicity in Iran

    Directory of Open Access Journals (Sweden)

    Khosro Sadeghniiat-Haghighi

    2013-01-01

    Full Text Available Background: This study assessed the effect of lead exposure on the peripheral nervous system in 40 hospitalized patients with lead toxicity [blood lead level (BLL >70 μg/dl] and compared their electrodiagnostic indices with the results of the control group. Materials and Methods: We assessed signs and symptoms of neuropathy in patients and conducted nerve conduction velocity (NCV in patients and control groups, then compared the results between the two groups. Results: Average duration of exposure to lead was 10.85 years. The mean BLL of patients was 100.32 μg/dl (SD = 18.42. The most common symptoms in patients were mood and sleep disturbance (64.1% and paresthesia (47.5%. Among the patients, all of the NCV indices in median, ulnar, and radial nerves were normal. On comparing the average indices of NCV in lead-exposed men with controls, significant reductions were noted in most of the indices and with prolonged distal motor latency and peak latency. Significant but weak correlations were found between BLL and some of the indices (P value < 0.05, r = 0.33-0.52. Conclusion: Comparing electrophysiological study indicators between case vs controls and considering the symptoms of patients, our study showed that patient may progress to sensory neuropathy.

  9. The use of a satellite derived vegetation index for assessment of the urban heat island effect

    Science.gov (United States)

    Gallo, Kevin P.; Tarpley, J. D.; Mcnab, Alan L.; Karl, Thomas R.; Brown, Jesslyn F.

    1993-01-01

    Satellite derived normalized difference (ND) vegetation index data, based on urban and rural region composed of a variety of land surface environments, are evaluated. These data are linearly related to the difference in observed urban and rural minimum temperatures. It is concluded that the difference in the ND index between urban and rural regions reflects the difference in the surface properties (evaporation and heat storage capacity) of these two environments and urban and rural minimum temperatures (the urban heat island effect).

  10. Assessment of Trace Metal Levels in Commonly Edible Vegetables from Selected Markets in Lagos State, Nigeria

    OpenAIRE

    Adu, A.A; Aderinola, O.J; Kusemiju, V

    2014-01-01

    Consumption of food contaminated with heavy metals is a major source of health problems for man and animals. Three commonly edible Leafy vegetables (Amaranthus hybridus, Celosia argentea ,Cochorus olitoris) from Agboju and Iba markets , Lagos Nigeria were sampled, identified, digested and analyzed with the aid of Atomic Absorption Spectrophotometer (AAS) as directed by APHA (American Public Health Association) to determine heavy metals concentration in them with the aim of ascertaining their...

  11. Assessing the reduction of the hydrological connectivity of gully systems through vegetation restoration: field experiments and numerical modelling

    Directory of Open Access Journals (Sweden)

    A. Molina

    2009-10-01

    well, as the error on the simulated total outflow volumes is below 13% for 15 out of 16 cases. However, predicting infiltration amounts is difficult: the high sensitivity of model results to some crucial hydraulic parameters (runoff width, hydraulic conductivity and sorptivity is one of the reasons why the relationships between model parameter values and gully features are relatively weak.

    The results obtained from the field experiments show that gully systems are key elements in the hydrological connectivity of degraded landscapes. The transfer of overland flow and sediment from the slopes towards the river system highly depends on the presence/absence of vegetation in the gully beds and should therefore be accounted for in assessments of landscape degradation and/or recovery.

  12. Effects of vegetation type on soil microbial community structure and catabolic diversity assessed by polyphasic methods in North China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Soil microbes play a major role in ecological processes and are closely associated with the aboveground plant community. In order to understand the effects of vegetation type on the characteristics of soil microbial communities, the soil microbial communities were assessed by plate counts, phospholipid fatty acid (PLFA) and Biolog microplate techniques in five plant communities, i.e., soybean field (SF), artificial turf (AT), artificial shrub (AS), natural shrub (NS), and maize field (MF) in Jinan, Shandong Province, North China. The results showed that plant diversity had little discernible effect on microbial biomass but a positive impact on the evennessof utilized substrates in Biolog microplate. Legumes could significantly enhance the number of cultural microorganisms, microbial biomass, and community catabolic diversity. Except for SF dominated by legumes, the biomass of fungi and the catabolic diversity of microbial community were higher in less disturbed soil beneath NS than in frequently disturbed soils beneath the other vegetation types. These results confirmed that high number of plant species, legumes, and natural vegetation types tend to support soil microbial communities with higher function. The present study also found a significant correlation between the number of cultured bacteria and catabolic diversity of the bacterial community. Different research methods led to varied results in this study. The combination of several approaches is recommended for accurately describing the characteristics of microbial communities in many respects.

  13. Preliminary assessment of late quaternary vegetation and climate of southeastern Utah based on analyses of packrat middens

    International Nuclear Information System (INIS)

    Packrat midden sequences from two caves (elevations 1585 and 2195 m; 5200 and 7200 ft) southwest of the Abajo Mountains in southeast Utah record vegetation changes that are attributed to climatic changes occurring during the last 13,000 years. These data are useful in assessing potential future climates at proposed nuclear waste sites in the area. Paleoclimates are reconstructed by defining modern elevational analogs for the vegetation assemblages identified in the middens. Based on the midden record, a climate most extreme from the present occurred prior to approximately 10,000 years before present (BP), when mean annual temperature was probably 3 to 4C (5.5 to 7F) cooler than present. However, cooling could not have exceeded 5C (9F) at 1585 m (5200 ft). Accompanying mean annual precipitation is estimated to have been from 35 to 140% greater than at present, with rainfall concentrated in the winter months. Vegetational changes beginning approximately 10,000 years BP are attributed to increased summer and mean annual temperatures, a decreasing frequency of spring freezes, and a shift from winter- to summer-dominant rainfall. Greater effective moisture than present is inferred at both cave sites from approximately 8000 to 4000 years BP. Modern flora was present at both sites by about 2000 years BP

  14. Probabilistic assessment of precipitation-triggered landslides: the role of vegetation

    Directory of Open Access Journals (Sweden)

    Muñoz Estefanía

    2016-01-01

    Full Text Available Landslides triggered by rainfall are one of the most common causes of disaster in tropical regions, characterized by having deep weathering soil profiles, steep slopes and high-intensity storms. The increasing number of landslides during wet season evidences the close relationship between hydro-climatic conditions as a triggering factor for the occurrence of landslides. In addition, the type of vegetation covering the slope affects the soil shear strength by the roots reinforcement, plants weight and changes in soil moisture due to transpiration and interception. This paper proposes a probabilistic methodology to study the slope stability on the long-term, considering different hydro-climatic conditions and the effect of vegetation cover in the soil moisture. The ecohydrological model developed by Rodríguez-Iturbe et al. [1] was used to determine the boundary conditions of the problem. To generate the pore pressure field, the flow equation was solved using the Finite Element Method and Finite Differences Method. Finally, the Limit Equilibrium Method was used to find the Factor of Safety. The stability of a hypothetical slope under certain hydro-climatic conditions and two types of vegetation was evaluated. The analysis showed that it is more likely that a grass-covered slope slides than a tree-covered slope, and that the average FS of the slope during wet and dry season is very similar, but the FS dispersion is higher when the probability and intensity of rainfall events increases.

  15. Physico-chemical evaluation and toxicity risk assessment of the urban rivers of Metro Cebu, Philippines

    International Nuclear Information System (INIS)

    Three prominent urban rivers in Metro Cebu were samples and analysed for their physico-chemical properties and their toxicity as to surfactant levels was evaluated using tilapia (Oreochromis niloticus L.). Surfactants in rivers, particularly the linear alkylbenzene sulfonates (LAS), ammonia (NH3), nitrate, nitrite and phosphate were determined colorimetrically using UV-Vis spectrophotometer. Physical parameters such as conductivity, salinity, temperature, pH and Dissolved Oxygen (DO) were determined in situ using a Multi-probe digital meter. Winkler Method was carried out to confirm the levels of DO in water samples. Results revealed that Guadalupe, Mahiga and Butuanon Downstream contain DO levels lower than 5 ppm, which is level needed to support aquatic life. This result further correlates the levels of NH3 in the samples with Guadalupe containing the highest NH3 level of 13.09 ppm, followed by, Butuanon Dowstream (8.20 ppm), Mahiga (5.95ppm) and Butuanon Upstream (1.22 ppm) which are all beyond the DENR standard limit of 0.5 ppm. The LAS levels were found high in Butuanon Downstream (3.35 ppm), Guadalupe River (1.51 ppm), followed by Mahiga (1.02 ppm), and Butuanon Upstream (0.42 ppm). All of the river water samples except for Butuanon Upstream were beyond the tolerable limit for surfactants as prescribed by the DENR for surface water which is 0.5 ppm. Nitrate and nitrite levels for all river samples were below the DEBR standard limit of 10.0 ppm. Only Guadalupe (0.91 ppm) and Mahiga (0.52 ppm) failed to meet the DENR standard of 0.4 ppm for phosphate. Definitive Test for toxicity of LAS to Tilapia juveniles after 96 h showed an LC50 of 7.6 ppm. This result was used for risk assessment of the three river systems for LAS. Toxicity Test of river samples showed 100% mortality for Guadalupe, Mahiga and Butuanon Downstream. Predicted Environment Concentrations (PEC) to Predicted No Effect Concentration (PNEC) ratio revealed that all river systems were at possible

  16. The relative teratogenic index and teratogenic potency: proposed components of developmental toxicity risk assessment.

    Science.gov (United States)

    Fabro, S; Shull, G; Brown, N A

    1982-01-01

    , 1.6; phenacemide, 3.3; trimethadione, 4.0; and sodium valproate, 4.1. For these data, tD05 and RTI clearly represent the differing teratogenic potencies and hazards of the tested compounds. it is suggested that these parameters may be useful in comparative teratogenicity studies and may be valuable components of developmental toxicity risk assessment.

  17. Exploratory breath analyses for assessing toxic dermal exposures of firefighters during suppression of structural burns.

    Science.gov (United States)

    Pleil, Joachim D; Stiegel, Matthew A; Fent, Kenneth W

    2014-09-01

    Firefighters wear fireproof clothing and self-contained breathing apparatus (SCBA) during rescue and fire suppression activities to protect against acute effects from heat and toxic chemicals. Fire services are also concerned about long-term health outcomes from chemical exposures over a working lifetime, in particular about low-level exposures that might serve as initiating events for adverse outcome pathways (AOP) leading to cancer. As part of a larger US National Institute for Occupational Safety and Health (NIOSH) study of dermal exposure protection from safety gear used by the City of Chicago firefighters, we collected pre- and post-fire fighting breath samples and analyzed for single-ring and polycyclic aromatic hydrocarbons as bioindicators of occupational exposure to gas-phase toxicants. Under the assumption that SCBA protects completely against inhalation exposures, any changes in the exhaled profile of combustion products were attributed to dermal exposures from gas and particle penetration through the protective clothing. Two separate rounds of firefighting activity were performed each with 15 firefighters per round. Exhaled breath samples were collected onto adsorbent tubes and analyzed with gas-chromatography-mass spectrometry (GC-MS) with a targeted approach using selective ion monitoring. We found that single ring aromatics and some PAHs were statistically elevated in post-firefighting samples of some individuals, suggesting that fire protective gear may allow for dermal exposures to airborne contaminants. However, in comparison to a previous occupational study of Air Force maintenance personnel where similar compounds were measured, these exposures are much lower suggesting that firefighters' gear is very effective. This study suggests that exhaled breath sampling and analysis for specific targeted compounds is a suitable method for assessing systemic dermal exposure in a simple and non-invasive manner. PMID:25190461

  18. Assessment of Protective and Antioxidant Properties of Tribulus Terrestris Fruits against Testicular Toxicity in Rats

    Directory of Open Access Journals (Sweden)

    Mostafa Abbas Shalaby

    2014-06-01

    Full Text Available Aims: This study was carried out to assess the protective and antioxidant activities of the methanolic extract of Tribulus terrestris fruits (METT against sodium valproate (SVP-induced testicular toxicity in rats. Material and methods: Fifty mature male rats were randomly divided into 5 equal groups (n=10. Group 1 was used normal (negative control, and the other four groups were intoxicated with SVP (500 mg/kg-1, orally during the last week of experiment. Group 2 was kept intoxicated (positive control and groups 3, 4 and 5 were orally pretreated with METT in daily doses 2.5, 5.0 and 10.0 mg/kg-1 for 60 days, respectively. Weights of sexual organs, serum testosterone, FSH and LH levels, semen picture, testicular antioxidant capacity and histopathology of testes were the parameters used in this study. Results: Oral pretreatment with METT significantly increased weights of testes and seminal vesicles; serum testosterone, FSH and LH levels and sperm motility, count and viability in SVP-intoxicated rats. METT enhanced the activity of testicular antioxidant enzymes and partially alleviated degenerative changes induced by SVP in testes. Conclusion: The pretreatment with METT has protective and antioxidant effects in SVP-intoxicated rats. Mechanisms of this protective effect against testicular toxicity may be due to the increased release of testosterone, FSH and LH and the enhanced tissue antioxidant capacity. These results affirm the traditional use of Tribulus terrestris fruits as an aphrodisiac for treating male sexual impotency and erectile dysfunction in patients. The study recommends that Tribulus terrestris fruits may be beneficial for male patients suffering from infertility. [J Intercult Ethnopharmacol 2014; 3(3.000: 113-118

  19. An experimental assessment of toxic potential of nanoparticle preparation of heavy metals in streptozotocin induced diabetes.

    Science.gov (United States)

    Gandhi, Sonia; Srinivasan, B P; Akarte, Atul Sureshrao

    2013-11-01

    Nanoparticle preparations of heavy metals have attracted enormous scientific and technological interest. Biologically produced nanoparticle preparations of heavy metals are elaborately described in traditional texts and being widely prescribed. The underlying interactions of nano preparations within the physiological fluids are key feature to understand their biological impact. In this perspective, we performed an experimental assessment of the toxicity potential of a marketed metallic preparation named Vasant Kusumakar Ras (VKR), wherein different heavy metals in composite form are reduced to nanoparticle size to produce the desired effect in diabetes and its complications. VKR (50mg/kg) was administered to Albino Wistar rats rendered diabetic using streptozotocin (90mg/kg) in 2 days old neonates. Anti-hyperglycemic effect was observed with VKR along with increased levels of plasma insulin. Renal variables including total proteins and albumin along with glomerular filtration rate were found to improve biochemically. The results were supplemented by effects on different inflammatory and growth factors like TNF-α, nitric oxide, TGF-β and VEGF. However, the results observed in kidney histopathology were not in accordance with the biochemical parameters. Inflammation observed in kidney was confirmed by immunostaining metallothionein, which was due to the accumulation of heavy metals. Furthermore, mercury accumulation in kidney further confirmed by autometallography, which activated mononuclear phagocyte system, which generated an immune response. This was further supported by increase in the extent of apoptosis in kidney tissues. In conclusion, nanoparticle preparations of heavy metals can be toxic to kidney if it is not regulated with respect to its surface chemistry and dosage.

  20. Toxic metals in children's toys and jewelry: Coupling bioaccessibility with risk assessment

    International Nuclear Information System (INIS)

    A total of 45 children's toys and jewelry were tested for total and bioaccessible metal concentrations. Total As, Cd, Sb, Cr, Ni, and Pb concentrations were 0.22–19, 0.01–139, 0.1–189, 0.06–846, 0.14–2894 and 0.08–860,000 mg kg−1. Metallic products had the highest concentrations, with 3–7 out of 13 samples exceeding the European Union safety limit for Cd, Pb, Cr, or Ni. However, assessment based on hazard index >1 and bioaccessible metal showed different trends. Under saliva mobilization or gastric ingestion, 11 out of 45 samples showed HI >1 for As, Cd, Sb, Cr, or Ni. Pb with the highest total concentration showed HI <1 for all samples while Ni showed the most hazard with HI up to 113. Our data suggest the importance of using bioaccessibility to evaluate health hazard of metals in children's toys and jewelry, and besides Pb and Cd, As, Ni, Cr, and Sb in children's products also deserve attention. - Highlights: • Contamination of toxic metals in children's toys and jewelry (TJ) were studied. • Metals including Pb, Cd, Cr, and Ni in some TJ exceeded the EU safety limits. • Hazard index of TJ was assessed based on bioaccessible metals via saliva mobilization and oral ingestion. • Hazard index was >> 1 for Ni, and unacceptable for As, Cd, Cr, and Sb in some TJ. - Assessment of health hazard of children's toys and jewelry based on bioaccessible metals suggested that besides Pb and Cd, As, Ni, Cr, and Sb in children's products deserve attention

  1. In vivo assessment of the toxic potential of Dissotis rotundifolia whole plant extract in Sprague–Dawley rats

    Directory of Open Access Journals (Sweden)

    Charles Ansah

    2016-07-01

    Conclusions: The results obtained from the sub-acute toxicological assessment of D. rotundifolia extract suggest that the extract is non-toxic at doses up to 1000 mg/kg/day administered for a period of 14 days.

  2. Implementing Toxicity Testing in the 21st Century (TT21C): Making safety decisions using toxicity pathways, and progress in a prototype risk assessment

    International Nuclear Information System (INIS)

    Risk assessment methodologies in toxicology have remained largely unchanged for decades. The default approach uses high dose animal studies, together with human exposure estimates, and conservative assessment (uncertainty) factors or linear extrapolations to determine whether a specific chemical exposure is ‘safe’ or ‘unsafe’. Although some incremental changes have appeared over the years, results from all new approaches are still judged against this process of extrapolating high-dose effects in animals to low-dose exposures in humans. The US National Research Council blueprint for change, entitled Toxicity Testing in the 21st Century: A Vision and Strategy called for a transformation of toxicity testing from a system based on high-dose studies in laboratory animals to one founded primarily on in vitro methods that evaluate changes in normal cellular signalling pathways using human-relevant cells or tissues. More recently, this concept of pathways-based approaches to risk assessment has been expanded by the description of ‘Adverse Outcome Pathways’ (AOPs). The question, however, has been how to translate this AOP/TT21C vision into the practical tools that will be useful to those expected to make safety decisions. We have sought to provide a practical example of how the TT21C vision can be implemented to facilitate a safety assessment for a commercial chemical without the use of animal testing. To this end, the key elements of the TT21C vision have been broken down to a set of actions that can be brought together to achieve such a safety assessment. Such components of a pathways-based risk assessment have been widely discussed, however to-date, no worked examples of the entire risk assessment process exist. In order to begin to test the process, we have taken the approach of examining a prototype toxicity pathway (DNA damage responses mediated by the p53 network) and constructing a strategy for the development of a pathway based risk assessment for a

  3. Assessment of locomotion behavioral defects induced by acute toxicity from heavy metal exposure in nematode Caenorhabditis elegans

    Institute of Scientific and Technical Information of China (English)

    WANG Dayong; XING Xiaojuan

    2008-01-01

    Locomotion behaviors are susceptible to disruption by a broad spectrum of chemicals and environmental stresses. However, no systematic testing of locomotion behavior defects induced by metal exposure has been conducted in the model organism of nematode Caenorhabditis elegans. In this study, the acute toxicity from heavy metal exposure on the locomotion behaviors was analyzed in nematodes. Endpoints of head thrash, body bend, forward turn, backward turn, and Omega/U turn were chosen to evaluate the locomotion behavioral defects. Our data suggest that the endpoints of head thrash, body bend, and forward turn will be useful for the evaluation of heavy metal toxicity in nematodes. The endpoint of head thrash could detect the toxicity from Cd, Co, Cr, Cu, Hg, and Pb exposures at a low concentration (2.5 μmol/L). The endpoint of body bend could be explored to evaluate the toxicity from all assayed heavy metal exposures at different concentrations, whereas the endpoint of forward turn will be more useful for the evaluation of heavy metal toxicity at high concentrations. Thus, endpoints of these locomotion behaviors establish a fast and economic way to assess the presence of acute toxicity from heavy metal exposure in nematode C. elegans.

  4. Toxicity assessment and bioaccumulation in zebrafish embryos exposed to carbon nanotubes suspended in Pluronic® F-108.

    Science.gov (United States)

    Wang, Ruhung; N Meredith, Alicea; Lee, Michael; Deutsch, Dakota; Miadzvedskaya, Lizaveta; Braun, Elizabeth; Pantano, Paul; Harper, Stacey; Draper, Rockford

    2016-08-01

    Carbon nanotubes (CNTs) are often suspended in Pluronic® surfactants by sonication, which may confound toxicity studies because sonication of surfactants can create degradation products that are toxic to mammalian cells. Here, we present a toxicity assessment of Pluronic® F-108 with and without suspended CNTs using embryonic zebrafish as an in vivo model. Pluronic® sonolytic degradation products were toxic to zebrafish embryos just as they were to mammalian cells. When the toxic Pluronic® fragments were removed, there was little effect of pristine multi-walled CNTs (pMWNTs), carboxylated MWNTs (cMWNTs) or pristine single-walled carbon nanotubes (pSWNTs) on embryo viability and development, even at high concentrations. A gel electrophoretic method coupled with Raman imaging was developed to measure the bioaccumulation of CNTs by zebrafish embryos, and dose-dependent uptake of CNTs was observed. These data indicate that embryos accumulate pMWNTs, cMWNTs and pSWNTs yet there is very little embryo toxicity. PMID:26559437

  5. Qualitative toxicity assessment of silver nanoparticles on the fresh water bacterial isolates and consortium at low level of exposure concentration.

    Science.gov (United States)

    Kumar, Deepak; Kumari, Jyoti; Pakrashi, Sunandan; Dalai, Swayamprava; Raichur, Ashok M; Sastry, T P; Mandal, A B; Chandrasekaran, N; Mukherjee, Amitava

    2014-10-01

    Silver nanoparticles (AgNPs) pose a high risk of exposure to the natural environment owing to their extensive usage in various consumer products. In the present study we attempted to understand the harmful effect of AgNPs at environmentally relevant low concentration levels (≤1ppm) towards two different freshwater bacterial isolates and their consortium. The standard plate count assay suggested that the AgNPs were toxic towards the fresh water bacterial isolates as well as the consortium, though toxicity was significantly reduced for the cells in the consortium. The oxidative stress assessment and membrane permeability studies corroborated with the toxicity data. The detailed electron microscopic studies suggested the cell degrading potential of the AgNPs, and the FT-IR studies confirmed the involvement of the surface groups in the toxic effects. No significant ion leaching from the AgNPs was observed at the applied concentration levels signifying the dominant role of the particle size, and size distribution in bacterial toxicity. The reduced toxicity for the cells in the consortium than the individual isolates has major significance in further studies on the ecotoxicity of the AgNPs.

  6. Potential toxic element fractionation and phytoavailability assessment in technosoils from former smelting and mining areas

    Science.gov (United States)

    Qasim, Bashar; Motelica-Heino, Mikael

    2014-05-01

    High metal and metalloid concentrations in soils have negative effects on terrestrial ecosystems and generate potential health risk. Mining and smelting activities are the major source of metal contamination by release a huge amounts of these potentially toxic elements (PTE) into the environment. Since the determination of the total concentration of PTE in soils does not give sufficient information about their mobility and toxicity, additional information on their bioavailability and their chemical speciation is required. Our study aimed at reporting the chemical fractionation and phytoavailability assessment of several PTE (Zn, Pb, Cd, As and Sb) in contaminated technosoils of two former smelting and mining areas. Soil samples were taken from a metallophyte grassland contaminated with Zn, Pb and Cd located at Mortagne - du -Nord (MDN) (North France) and from a former mining settling basin contaminated with As, Pb and Sb located at la Petite Faye (LPF) (Limoges district, France). Two sequential extraction schemes were used to evaluate the PTE speciation in various technosoils as operationally defined fractions. The extraction schemes used in this study were the Tessier's scheme and a modified BCR scheme. The fractions were rearranged into four equivalent fractions defined as acid soluble, reducible, oxidisable and residual fraction. To assess the metals and metalloids phytoavailability a series of selective single extraction procedures (CaCl2, NaNO3, NH4NO3, DTPA and EDTA) were used together with short-term germination tests with dwarf beans whose primary leaves were analyzed for their PTE concentration after 21 days of sowing under controlled conditions (16h light/8h darkness regime, 25°C/21°C, relative humidity of 55 - 65% and photon flux of 150 μE m-2s-1). Our results indicates that Zn, Cd and Pb were mainly associated with the acid soluble and reducible fractions for the MDN site, while As, Sb and Pb were mostly associated with residual fraction for the LPF

  7. Toxicity assessment in marine sediment for the Terra Nova environmental effects monitoring program (1997-2010)

    Science.gov (United States)

    Whiteway, Sandra A.; Paine, Michael D.; Wells, Trudy A.; DeBlois, Elisabeth M.; Kilgour, Bruce W.; Tracy, Ellen; Crowley, Roger D.; Williams, Urban P.; Janes, G. Gregory

    2014-12-01

    This paper discusses toxicity test results on sediments from the Terra Nova offshore oil development. The Terra Nova Field is located on the Grand Banks approximately 350 km southeast of Newfoundland (Canada). The amphipod (Rhepoxynius abronius) survival and solid phase luminescent bacteria (Vibrio fischeri, or Microtox) assays were conducted on sediment samples collected from approximately 50 stations per program year around Terra Nova during baseline (1997), prior to drilling, and in 2000, 2001, 2002, 2004, 2006, 2008 and 2010 after drilling began. The frequency of toxic responses in the amphipod toxicity test was low. Of the ten stations that were toxic in environmental effects monitoring (EEM) years, only one (station 30(FE)) was toxic in more than one year and could be directly attributed to Terra Nova project activities. In contrast, 65 (18%) of 364 EEM samples were toxic to Microtox. Microtox toxicity in EEM years was not related to distance from Terra Nova drill centres or concentrations of >C10-C21 hydrocarbons or barium, the primary constituents of the synthetic-based drill muds used at Terra Nova. Of the variables tested, fines and strontium levels showed the strongest (positive) correlations with toxicity. Neither fines nor strontium levels were affected by drill cuttings discharge at Terra Nova, except at station 30(FE) (and that station was not toxic to Microtox). Benthic macro-invertebrate abundance, richness and diversity were greater in toxic than in non-toxic sediments. Therefore, Microtox responses indicating toxicity were associated with positive biological responses in the field. This result may have been an indirect function of the increased abundance of most invertebrate taxa in less sandy sediments with higher gravel content, where fines and strontium levels and, consequently, toxicity to Microtox were high; or chemical substances released by biodegradation of organic matter, where invertebrates are abundant, may be toxic to Microtox. Given

  8. Effects of Oil-Contaminated Sediments on Submerged Vegetation: An Experimental Assessment of Ruppia maritima.

    Directory of Open Access Journals (Sweden)

    Charles W Martin

    Full Text Available Oil spills threaten the productivity of ecosystems through the degradation of coastal flora and the ecosystem services these plants provide. While lab and field investigations have quantified the response of numerous species of emergent vegetation to oil, the effects on submerged vegetation remain uncertain. Here, we discuss the implications of oil exposure for Ruppia maritima, one of the most common species of submerged vegetation found in the region affected by the recent Deepwater Horizon oil spill. We grew R. maritima in a range of manipulated sediment oil concentrations: 0, 0.26, 0.53, and 1.05 mL oil /L tank volume, and tracked changes in growth (wet weight and shoot density/length, reproductive activity (inflorescence and seed production, root characteristics (mass, length, diameter, and area, and uprooting force of plants. While no statistical differences were detected in growth, plants exhibited significant changes to reproductive output, root morphology, and uprooting force. We found significant reductions in inflorescences and fruiting bodies at higher oil concentrations. In addition, the roots growing in the high oil were shorter and wider. Plants in medium and high oil required less force to uproot. A second experiment was performed to separate the effects of root morphology and oiled sediment properties and indicated that there were also changes to sediment cohesion that contributed to a reduction in uprooting forces in medium and high oil. Given the importance of sexual reproduction for these plants, oil contamination may have substantial population-level effects. Moreover, areas containing buried oil may be more susceptible to high energy storm events due to the reduction in uprooting force of foundation species such as R. maritima.

  9. Plutonium uptake and behavior in vegetation of the desert southwest: a preliminary assessment.

    Science.gov (United States)

    Caldwell, Eric; Duff, Martine; Ferguson, Caitlin; Coughlin, Daniel

    2011-09-01

    Eight species of desert vegetation and associated soils were collected from the Nevada National Security Site (N2S2) and analyzed for 238Pu and 239 + 240Pu concentrations. Amongst the plant species sampled were: atmospheric elemental accumulators (moss and lichen), the very slow growing, long-lived creosote bush and the rapidly growing, short-lived cheatgrass brome. The diversity of growth strategies provided insight into the geochemical behavior and bio-availability of Pu at the N2S2. The highest concentrations of Pu were measured in the onion moss (24.27 Bq kg-1 238Pu and 52.78 Bq kg-1 239 + 240Pu) followed by the rimmed navel lichen (8.18 Bq kg-1 and 18.4 Bq kg-1 respectively), pointing to the importance of eolian transport of Pu. Brome and desert globemallow accumulated between 3 and 9 times higher concentrations of Pu than creosote and sage brush species. These results support the importance of species specific elemental accumulation strategies rather than exposure duration as the dominant variable influencing Pu concentrations in these plants. Total vegetation elemental concentrations of Ce, Fe, Al, Sm and others were also analyzed. Strong correlations were observed between Fe and Pu. This supports the conclusion that Pu was accumulated as a consequence of the active accumulation of Fe and other plant required nutrients. Cerium and Pu are considered to be chemical analogs. Strong correlations observed in plants support the conclusion that these elements displayed similar geochemical behavior in the environment as it related to the biochemical uptake process of vegetation. Soils were also sampled in association with vegetation samples. This allowed for the calculation of a concentration ratio (CR). The CR values for Pu in plants were highly influenced by the heterogeneity of Pu distribution among sites. Results from the naturally occurring elements of concern were more evenly distributed between sample sites. This allowed for the development of a pattern of

  10. The importance of experimental time when assessing the effect of temperature on toxicity in poikilotherms

    OpenAIRE

    Norhave, Nils J.; Spurgeon, David; Svendsen, Claus; Cedergreen, Nina

    2014-01-01

    Temperature is an important factor affecting toxicity, determining chemical toxicokinetics and toxicodynamics in poikilothermic organisms. As also metabolic rates are affected by temperature, interactions between the emergence of toxic effects and time are very likely. The aim of this study was to investigate how temperature affected the toxicity of copper towards the nematode Caenorhabditis elegans when measured during short fixed timeframes compared to during full life-cycles. Copper toxici...

  11. Assessing Vegetation Structure and Dynamics in a Chihuahuan Grassland-Shrubland Ecotone Using the Relationship Between Remote-Sensed Vegetation Phenology and Precipitation

    Science.gov (United States)

    Moreno de las Heras, M.; Diaz-Sierra, R.; Turnbull, L.; Wainwright, J.

    2014-12-01

    Land degradation usually involves largely irreversible vegetation changes in drylands. A typical case of vegetation change is the shrub-encroachment process that has been taking place over the last 150 years in the Chihuahuan Desert, where large areas of grasslands dominated by perennial grass species (black and blue grama) have transitioned to shrublands dominated by woody species (mainly creosotebush and mesquite), accompanied by accelerated water and wind erosion. An array of mechanisms are involved in this process, including external triggering factors such as precipitation variations and land-use change, and endogenous amplifying mechanisms brought about by soil erosion-vegetation feedbacks. We analyze the structure and dynamics of vegetation at an 18-km2 grassland-shrubland ecotone in the northern edge of the Chihuahuan desert (McKenzie Flats, Sevilleta National Wildlife Refuge, New Mexico) by investigating the relationship between decade-scale (2000-13) records of medium-resolution remote sensing of vegetation phenology (MODIS NDVI) and precipitation. Our analysis indicates that spatial variations in the NDVI-rainfall relationship reflect functional differences in leaf phenology and water use for herbaceous and shrub vegetation. Herbaceous vegetation shows quick growth pulses associated with short-term (previous 2 months) precipitation, while shrubs show a slow response to medium-term (previous 5 months) precipitation. We use these relationships to (a) determine the broad-scale spatial distribution of dominant vegetation types, and to (b) decompose the NDVI signal into partial net primary production (NPP) components for herbaceous vegetation and shrubs across the study site. We further analyze the influence of inter-annual variations in seasonal precipitation on remotely sensed NPP. Plant growth for herbaceous vegetation is particularly synchronized with monsoonal summer rainfall. For shrubs, annual NPP is better explained by winter plus summer precipitation

  12. Assessing Land Degradation and Desertification Using Vegetation Index Data: Current Frameworks and Future Directions

    Directory of Open Access Journals (Sweden)

    Thomas P. Higginbottom

    2014-10-01

    Full Text Available Land degradation and desertification has been ranked as a major environmental and social issue for the coming decades. Thus, the observation and early detection of degradation is a primary objective for a number of scientific and policy organisations, with remote sensing methods being a candidate choice for the development of monitoring systems. This paper reviews the statistical and ecological frameworks of assessing land degradation and desertification using vegetation index data. The development of multi-temporal analysis as a desertification assessment technique is reviewed, with a focus on how current practice has been shaped by controversy and dispute within the literature. The statistical techniques commonly employed are examined from both a statistical as well as ecological point of view, and recommendations are made for future research directions. The scientific requirements for degradation and desertification monitoring systems identified here are: (I the validation of methodologies in a robust and comparable manner; and (II the detection of degradation at minor intensities and magnitudes. It is also established that the multi-temporal analysis of vegetation index data can provide a sophisticated measure of ecosystem health and variation, and that, over the last 30 years, considerable progress has been made in the respective research.

  13. Digital photography for assessing the link between vegetation phenology and CO2 exchange in two contrasting northern ecosystems

    Science.gov (United States)

    Linkosalmi, Maiju; Aurela, Mika; Tuovinen, Juha-Pekka; Peltoniemi, Mikko; Tanis, Cemal M.; Arslan, Ali N.; Kolari, Pasi; Böttcher, Kristin; Aalto, Tuula; Rainne, Juuso; Hatakka, Juha; Laurila, Tuomas

    2016-09-01

    Digital repeat photography has become a widely used tool for assessing the annual course of vegetation phenology of different ecosystems. By using the green chromatic coordinate (GCC) as a greenness measure, we examined the feasibility of digital repeat photography for assessing the vegetation phenology in two contrasting high-latitude ecosystems. Ecosystem-atmosphere CO2 fluxes and various meteorological variables were continuously measured at both sites. While the seasonal changes in GCC were more obvious for the ecosystem that is dominated by annual plants (open wetland), clear seasonal patterns were also observed for the evergreen ecosystem (coniferous forest). Daily and seasonal time periods with sufficient solar radiation were determined based on images of a grey reference plate. The variability in cloudiness had only a minor effect on GCC, and GCC did not depend on the sun angle and direction either. The daily GCC of wetland correlated well with the daily photosynthetic capacity estimated from the CO2 flux measurements. At the forest site, the correlation was high in 2015 but there were discernible deviations during the course of the summer of 2014. The year-to-year differences were most likely generated by meteorological conditions, with higher temperatures coinciding with higher GCCs. In addition to depicting the seasonal course of ecosystem functioning, GCC was shown to respond to environmental changes on a timescale of days. Overall, monitoring of phenological variations with digital images provides a powerful tool for linking gross primary production and phenology.

  14. High resolution vegetation assessment with beta-diversity – a moving window approach

    Directory of Open Access Journals (Sweden)

    Sandor Bartha

    2011-11-01

    Full Text Available Monitoring designs are often suffering from the inherent non-stationarity of the monitored systems. To overcome this limition, we propose a sampling designs based on high resolution mapping and spatial analyses with double spatial scaling process. Applying for vegetation, we record the presence of plant species along 26 m or 52 m long belt transects of 520 (or 1040 units of 0.5 cm x 0.5 cm contiguous microquadrats. Beta diversity (represented as the diversity of species combinations is estimated by subsequent computerised samplings from the baseline transect data sets. Beta diversity is scaled with changing resolutions across a range of scales from 5 cm x 5 cm to 5 cm x 500 cm. Second, it is also scaled using moving window. Local maximum of beta diversity is repeatedly calculated in 5 m extent observational windows shifted along the transect with 1 m lag, and the spatial variability of vegetation is visualized by the related beta-diversity profile. Using field example, we demonstrate that beta diversity, when applied with our methodology, is a sensitive indicator, and it can reveal more information than alpha or gamma diversity.

  15. Subacute toxicity assessment of diflubenzuron, an insect growth regulator, in adult male rats.

    Science.gov (United States)

    de Barros, Aline Lima; Cavalheiro, Gabriela Finoto; de Souza, Alexsandra Vila Maior; Traesel, Giseli Karenina; Anselmo-Franci, Janete A; Kassuya, Cândida Aparecida Leite; Arena, Arielle Cristina

    2016-04-01

    Diflubenzuron (DFB), an insecticide and acaricide insect growth regulator, can be used in agriculture against insect predators and in public health programs, to control insects and vectors, mainly Aedes aegypti larvae. Due to the lack of toxicological assessments of this compound, the objective of the present study was to evaluate the toxicological effects of subacute exposure to the DFB insecticide in adult male rats. Adult male rats were exposed (gavage) to 0, 2, 4, or 8 mg/kg of DFB for 28 days. No clinical signs of toxicity were observed in the DFB-treated animals of the experimental groups. However, there was an increase in serum levels of alanine aminotransferase in the group that received 8 mg/kg/DFB/day and urea at doses of 4 and 8 mg/kg/DFB/day, without altering other biochemical or hematological parameters. The subacute exposure to the lowest dose of DFB caused significant decrease in testis weight, daily sperm production, and in number of sperm in the epididymis in relation to the control group. However, no alterations were observed in the sperm morphology, testicular, epididymis, liver and kidney histology, or testosterone levels. These findings unveiled the hazardous effects of DFB on male reproduction after the subacute exposure and special attention should be addressed to the effects of low doses of this pesticide.

  16. Degradation of Thiamethoxam in aqueous solution by ozonation: Influencing factors, intermediates, degradation mechanism and toxicity assessment.

    Science.gov (United States)

    Zhao, Qinghua; Ge, Yanan; Zuo, Peng; Shi, Dong; Jia, Shouhua

    2016-03-01

    This paper focuses on the degradation of Thiamethoxam (THIA) in aqueous solution by ozonation. Four influencing factors: pH, THIA initial concentration, ozone concentration and temperature were investigated in order to optimize the conditions, and pH showed the greatest impact; the removal efficiency reached up to 71.19% under the condition of pH 5-11, THIA initial concentration 50-300 mg L(-1), the ozone concentration 10-22.5 mg L(-1) at 293-308 K after 90 min. Four main intermediates were separated and identified and the possible degradation mechanism was proposed. The luminous intensity of photobacteria and the chemical oxygen demand (COD) were measured to assess the changes of toxicity and mineralization in ozonation process, and results showed that the inhibition rate decreased by 60% and 76% of COD was removed after 180 min with the THIA initial concentration was 200 mg L(-1). Our study powerfully demonstrates that the degradation of THIA in aqueous solution by ozonation is a promising technology.

  17. Verified spider bites in Oregon (USA) with the intent to assess hobo spider venom toxicity.

    Science.gov (United States)

    McKeown, Nathanael; Vetter, Richard S; Hendrickson, Robert G

    2014-06-01

    This study compiled 33 verified spider bites from the state of Oregon (USA). The initial goal was to amass a series of bites by the hobo spider to assess whether it possesses toxic venom, a supposition which is currently in a contested state. None of the 33 bites from several spider species developed significant medical symptoms nor did dermonecrosis occur. The most common biters were the yellow sac spider, Cheiracanthium mildei (N = 10) and orb-weavers of the genus Araneus (N = 6). There were 10 bites from three genera of funnel web spiders of the family Agelenidae including one hobo spider bite and one from the congeneric giant house spider which is readily confused as a hobo spider. The hobo spider bite resulted in pain, redness, twitching in the calf muscle and resolved in 12 h. Also generated from this study were possibly the first records of bites from spiders of the genera Callobius (Amaurobiidae) and Antrodiaetus (Antrodiaetidae), both with minor manifestations.

  18. Health assessment of gasoline and fuel oxygenate vapors: subchronic inhalation toxicity.

    Science.gov (United States)

    Clark, Charles R; Schreiner, Ceinwen A; Parker, Craig M; Gray, Thomas M; Hoffman, Gary M

    2014-11-01

    Sprague Dawley rats were exposed via inhalation to vapor condensates of either gasoline or gasoline combined with various fuel oxygenates to assess whether their use in gasoline influences the hazard of evaporative emissions. Test substances included vapor condensates prepared from an EPA described "baseline gasoline" (BGVC), or gasoline combined with methyl tertiary butyl ether (G/MTBE), ethyl t-butyl ether (G/ETBE), t-amyl methyl ether (G/TAME), diisopropyl ether (G/DIPE), ethanol (G/EtOH), or t-butyl alcohol (G/TBA). Target concentrations were 0, 2000, 10,000 or 20,000mg/m(3) and exposures were for 6h/day, 5days/week for 13weeks. A portion of the animals were maintained for a four week recovery period to determine the reversibility of potential adverse effects. Increased kidney weight and light hydrocarbon nephropathy (LHN) were observed in treated male rats in all studies which were reversible or nearly reversible after 4weeks recovery. LHN is unique to male rats and is not relevant to human toxicity. The no observed effect level (NOAEL) in all studies was 10,000mg/m(3), except for G/MTBE (<2000) and G/TBA (2000). The results provide evidence that use of the studied oxygenates are unlikely to increase the hazard of evaporative emissions during refueling, compared to those from gasoline alone. PMID:25020274

  19. Changes in vegetative coverage of the Hongze Lake national wetland nature reserve: a decade-long assessment using MODIS medium-resolution data

    Science.gov (United States)

    Yu, Kun; Hu, Chuanmin

    2013-01-01

    Wetlands are important ecosystems on Earth. However, global wetland coverage is being reduced due to both anthropogenic and natural effects. Thus, assessment of temporal changes in vegetative coverage, as a measure of the wetland health, is critical to help implement effective management plans and provide inputs for climate-related research. In this work, 596 moderate-resolution imaging spectroradiometer (MODIS) 250-m resolution images of the Hongze Lake national wetland nature reserve from 2000 to 2009 were used to study the vegetative coverage (above the water surface) of the reserve. Three vegetation indices [normalized difference vegetation index (NDVI), enhanced VI (EVI), and floating algae index (FAI)] were compared to evaluate their effectiveness in assessing relative changes. FAI was less sensitive than NDVI and EVI to aerosol effects and showed less statistical error than NDVI and EVI. Long-term FAI data revealed clear seasonal cycles in vegetative coverage in the 113-km2 core area of the reserve, with annual maximal coverage relatively stable after 2004. This suggests that the national wetland nature reserve was well protected through the study period. However, vegetative coverage decreased due to the flooding event in 2003. Moreover, correlation analysis showed that annual sunshine duration collectively played a significant role in affecting the wetland vegetative coverage.

  20. Heavy metal content in vegetables and fruits cultivated in Baia Mare mining area (Romania) and health risk assessment.

    Science.gov (United States)

    Roba, Carmen; Roşu, Cristina; Piştea, Ioana; Ozunu, Alexandru; Baciu, Călin

    2016-04-01

    Information about heavy metal concentrations in food products and their dietary intake are essential for assessing the health risk of local inhabitants. The main purposes of the present study were (1) to investigate the concentrations of Zn, Cu, Pb, and Cd in several vegetables and fruits cultivated in Baia Mare mining area (Romania); (2) to assess the human health risk associated with the ingestion of contaminated vegetables and fruits by calculating the daily intake rate (DIR) and the target hazard quotient (THQ); and (3) to establish some recommendations on human diet in order to assure an improvement in food safety. The concentration order of heavy metals in the analyzed vegetable and fruit samples was Zn > Cu > Pb > Cd. The results showed the heavy metals are more likely to accumulate in vegetables (10.8-630.6 mg/kg dw for Zn, 1.4-196.6 mg/kg dw for Cu, 0.2-155.7 mg/kg dw for Pb, and 0.03-6.61 mg/kg dw for Cd) than in fruits (4.9-55.9 mg/kg dw for Zn, 1.9-24.7 mg/kg dw for Cu, 0.04-8.82 mg/kg dw for Pb, and 0.01-0.81 mg/kg dw for Cd). Parsley, kohlrabi, and lettuce proved to be high heavy metal accumulators. By calculating DIR and THQ, the data indicated that consumption of parsley, kohlrabi, and lettuce from the area on a regular basis may pose high potential health risks to local inhabitants, especially in the area located close to non-ferrous metallurgical plants (Romplumb SA and Cuprom SA) and close to Tăuții de Sus tailings ponds. The DIR for Zn (85.3-231.6 μg/day kg body weight) and Cu (25.0-44.6 μg/day kg body weight) were higher in rural areas, while for Pb (0.6-3.1 μg/day kg body weight) and Cd (0.22-0.82 μg/day kg body weight), the DIR were higher in urban areas, close to the non-ferrous metallurgical plants SC Romplumb SA and SC Cuprom SA. The THQ for Zn, Cu, Pb, and Cd was higher than 5 for health risks.

  1. Identification of phototransformation products of the antiepileptic drug gabapentin: Biodegradability and initial assessment of toxicity.

    Science.gov (United States)

    Herrmann, Manuel; Menz, Jakob; Olsson, Oliver; Kümmerer, Klaus

    2015-11-15

    The anticonvulsant drug Gabapentin (GAB) is used for the treatment of various diseases (e.g. epilepsy, bipolar disorder, neuropathic pain) and is being consumed in high amounts. As GAB is not metabolized and shows a weak elimination in sewage treatment plants (STPs), it has been detected in surface water and even in raw potable water. Moreover, the confirmed teratogenic effects of GAB indicate the need for further investigations regarding options for the elimination of GAB in the water cycle. Little is known about the behavior of GAB during treatment with UV light, which is normally used for the disinfection of potable water and discussed for advanced wastewater treatment. In this study, GAB was exposed to polychromatic UV irradiation at different initial concentrations in aqueous solution. Afterwards the structures of the resulting phototransformation products (PTPs) were identified and elucidated by means of high-resolution mass spectrometry. GAB and photolytic mixtures were submitted to the Closed Bottle Test (CBT; OECD 301 D) to assess biodegradability. Furthermore, the toxicity of GAB and its photolytic mixtures was initially addressed on screening level using a modified luminescent bacteria test (LBT) and the umu-test (ISO/FDIS 13829). Environmentally realistic concentrations of GAB were disclosed by predicting STP influent concentrations (24.3 and 23.2 μg L(-1)). GAB with initial concentration of 100 mg L(-1) was eliminated by 80% after 128 min of direct UV irradiation, but just 9% of non-purgeable organic carbon (NPOC) was removed indicating the formation of dead-end transformation products (TPs). Structures of different PTPs were elucidated and several identical PTPs could also be identified at lower initial treatment concentrations (20 mg L(-1), 5 mg L(-1), 1 mg L(-1) and 0.1 mg L(-1)). GAB was classified as not readily biodegradable. Moreover, photo treatment did not result in better biodegradable PTPs. With increasing UV treatment duration, photolytic

  2. Greenhouse gas emissions of imported and locally produced fruit and vegetable commodities: A quantitative assessment

    International Nuclear Information System (INIS)

    Highlights: • Green house gas (GHG) emission of selected fruit and vegetables (SFVs) estimated. • Production and transport – most energy-intensive life cycle stages considered. • Sourcing SFVs from non-European countries causes much GHG emissions. • Increased UK production of SFVs offers considerable emission savings. • Sourcing SFVs from Europe can help make considerable GHG emission savings. - Abstract: Today considerable efforts are being made in identifying means of further energy efficiencies within the UK food system. Current air importation of fruit and vegetables (FVs) generates large amounts of greenhouse gas (GHG) emissions part of which could be avoided. Local food production has been recognized as an environmentally feasible alternative production option and could help reduce GHG emissions, as required under the legally binding emissions targets stipulated by the UK Climate Change Act 2008. Climate change impacts of FVs importation were determined for a selection of five indigenous FV commodities, namely: apples, cherries, strawberries, garlic and peas. Carbon dioxide equivalents (CO2e) emissions associated with the production and transport stages were calculated using the sample of selected fruit and vegetables (SFVs). The latter stage includes three diverse geographic locations/regions for emissions comparison, namely the UK, Europe and non-European (NE) countries. On average (across the five SFVs), NE commodities, all in fresh/chilled state, were found to contain embedded (arising from production, air freighting and distribution within the UK) GHG emissions of 10.16 kg CO2e/kg. This is 9.66 kg more CO2e emissions compared to a kilogram of these commodities produced and supplied locally. A scenario-based approach determined the level of emissions savings that could be achieved by local FVs production in the UK. The least dramatic change of SCENARIO-1 (25% reduction in NE SFVs imports by increasing their local production by the same amount

  3. Estimation of Heavy Metal in Vegetables from Different Market Sites of Tribal Based Ranchi City through Icp-Oes and to Assess Health Risk

    OpenAIRE

    Ratna Ghosh; Reshma Xalxo; Manik Ghosh

    2013-01-01

    Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES) was used to estimate and evaluate the levels of heavy metals in vegetables collected from various sites of Ranchi city (tribal dominated population) followed by health risk assessment by determining Metal Pollution Index (MPI), Daily intake of metal (DIM) and Health Risk Index (HRI). The concentration levels of Pb, Cd and Ni in vegetables were found to contain beyond than the permissible PFA limit. All sites showed quite a f...

  4. Use of passive samplers for improving oil toxicity and spill effects assessment.

    Science.gov (United States)

    Letinski, Daniel; Parkerton, Thomas; Redman, Aaron; Manning, Ryan; Bragin, Gail; Febbo, Eric; Palandro, David; Nedwed, Tim

    2014-09-15

    Methods that quantify dissolved hydrocarbons are needed to link oil exposures to toxicity. Solid phase microextraction (SPME) fibers can serve this purpose. If fibers are equilibrated with oiled water, dissolved hydrocarbons partition to and are concentrated on the fiber. The absorbed concentration (Cpolymer) can be quantified by thermal desorption using GC/FID. Further, given that the site of toxic action is hypothesized as biota lipid and partitioning of hydrocarbons to lipid and fibers is well correlated, Cpolymer is hypothesized to be a surrogate for toxicity prediction. To test this method, toxicity data for physically and chemically dispersed oils were generated for shrimp, Americamysis bahia, and compared to test exposures characterized by Cpolymer. Results indicated that Cpolymer reliably predicted toxicity across oils and dispersions. To illustrate field application, SPME results are reported for oil spills at the Ohmsett facility. SPME fibers provide a practical tool to improve characterization of oil exposures and predict effects in future lab and field studies.

  5. Heavy metal analysis in soils and vegetation for assessing emission fields near tunnel ventilation systems

    International Nuclear Information System (INIS)

    In the environment of the ventilation system of the Tauern and Katschberg tunnels, lead, cadmium, zinc and copper were determined in soil and vegetation samples in order to determine the emission fields. Thalli of Pseudevernia furfuracea in addition were used as active monitors. The surface-level exhaust portals produce relatively small atmospheric pollution fields. Via the detached exhaust tower at Urbanalm/Mosermandl (2.000 msm), a long-distance transport: Lead concentrations in soils are above average as far away as 1.5 kms of distance. The solubility of heavy metals increases in the order Pb< Cu< Zn< Cd; it is higher in silicate soils than in carbonate soils. In the hay samples from Urbanalm, no appreciable heavy metal concentrations could be recognized. The changes are not significant in the last 4 years. (orig.)

  6. A Technology-Assisted Learning Setup as Assessment Supplement for Three Persons with a Diagnosis of Post-Coma Vegetative State and Pervasive Motor Impairment

    Science.gov (United States)

    Lancioni, Giulio E.; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Buonocunto, Francesca; Sacco, Valentina; Colonna, Fabio; Navarro, Jorge; Lanzilotti, Crocifissa; Bosco, Andrea; Megna, Gianfranco; De Tommaso, Marina

    2009-01-01

    Post-coma persons in an apparent condition of vegetative state and pervasive motor impairment pose serious problems in terms of assessment and intervention options. A technology-based learning assessment procedure might serve for them as a diagnostic supplement with possible implications for rehabilitation intervention. The learning assessment…

  7. Dialkylphosphates (DAPs) in fruits and vegetables may confound biomonitoring in organophosphorus insecticide exposure and risk assessment.

    Science.gov (United States)

    Zhang, Xiaofei; Driver, Jeffrey H; Li, Yanhong; Ross, John H; Krieger, Robert I

    2008-11-26

    Trace residues of organophosphorus (OP) pesticides are associated with fruits and vegetables that have been sprayed with those OP pesticides to guard against insect pests. Human dietary exposure to these OP pesticides is commonly estimated by measuring the amount of OP metabolites in urine, assuming a stoichiometric relationship between a metabolite and its parent insecticide. Dialkylphosphates (DAPs) are the OP metabolites that are most often used as markers in such biomonitoring studies. However, abiotic hydrolysis, photolysis, and plant metabolism can convert OP chemicals (OP residues) to DAP residues on or in the fruits and vegetables. To evaluate the extent of these conversions, OPs and DAPs were measured in 153 produce samples. These samples from 2 lots were known to contain OP insecticide residues based on routine monitoring by California producers and shippers. A total of 12 OPs were quantified, including mevinphos, naled, acephate, methamidophos, oxidemeton-methyl, azinphos-methyl, dimethoate, malathion, methidathion, phosmet, chlorpyrifos, and diazinon. All OP insecticide residues were below their respective residue tolerances in 2002-2004. A total of 91 of 153 samples (60%) contained more DAP residues than parent OPs. The mean mole fractions [DAPs/(DAPs + OPs)] for the first and second lots of produce were 0.62 and 0.50, respectively, and the corresponding geometric means were 0.55 and 0.34. The corresponding mean mole ratios (DAPs/OP) were 7.1 and 3.4, with geometric means of 2.1 and 0.9. Any preformed DAPs ingested in the diet that are excreted in urine may inflate the estimated absorbed OP insecticide doses in occupational and environmental studies. In subsequent prospective studies, time-dependent production of dimethylphosphate (DMP) and dimethylthiophosphate (DMTP) in strawberries and leaves following malathion sprays occurred concomitant with the disappearance of the parent insecticide and its oxon. DAPs are more persistent in plants and produce

  8. How Universal Is the Relationship between Remotely Sensed Vegetation Indices and Crop Leaf Area Index? A Global Assessment

    Directory of Open Access Journals (Sweden)

    Yanghui Kang

    2016-07-01

    Full Text Available Leaf Area Index (LAI is a key variable that bridges remote sensing observations to the quantification of agroecosystem processes. In this study, we assessed the universality of the relationships between crop LAI and remotely sensed Vegetation Indices (VIs. We first compiled a global dataset of 1459 in situ quality-controlled crop LAI measurements and collected Landsat satellite images to derive five different VIs including Simple Ratio (SR, Normalized Difference Vegetation Index (NDVI, two versions of the Enhanced Vegetation Index (EVI and EVI2, and Green Chlorophyll Index (CIGreen. Based on this dataset, we developed global LAI-VI relationships for each crop type and VI using symbolic regression and Theil-Sen (TS robust estimator. Results suggest that the global LAI-VI relationships are statistically significant, crop-specific, and mostly non-linear. These relationships explain more than half of the total variance in ground LAI observations (R2 > 0.5, and provide LAI estimates with RMSE below 1.2 m2/m2. Among the five VIs, EVI/EVI2 are the most effective, and the crop-specific LAI-EVI and LAI-EVI2 relationships constructed by TS, are robust when tested by three independent validation datasets of varied spatial scales. While the heterogeneity of agricultural landscapes leads to a diverse set of local LAI-VI relationships, the relationships provided here represent global universality on an average basis, allowing the generation of large-scale spatial-explicit LAI maps. This study contributes to the operationalization of large-area crop modeling and, by extension, has relevance to both fundamental and applied agroecosystem research.

  9. Assessment of toxicity in waters due to heavy metals derived from atmospheric deposition using Vibrio fischeri.

    Science.gov (United States)

    Cukurluoglu, Sibel; Muezzinoglu, Aysen

    2013-01-01

    Water toxicity originating from the atmospheric deposition of six heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) was investigated on Vibrio fischeri activity in Izmir, Turkey. A LUMIStox® test was applied to dry and wet deposition samples and metal solutions. The inhibition levels and effective toxicity concentrations of these samples and solutions were determined. Interactive toxicity effects among the metals were investigated. When the impacts of the synthetic single heavy metal solutions were compared with each other, a toxicity ranking of Cr>Cd>Pb>Cu>Zn>Ni was obtained in order of decreasing severity. The total effective concentrations of these six metals were in the ranges of 0.074-0.221 mg/L and 0.071-0.225 mg/L for receiving aqueous solutions of dry and wet atmospheric depositions, respectively. The toxicity data showed that the wet deposition samples were 15% more toxic than the dry deposition samples. The interactive toxicity effects of the heavy metals in both dry and wet deposition samples were classified as antagonistic. High levels of heavy metals deposited in dissolved form may constitute an important input in the biochemical cycle and may have significant impacts. PMID:23030388

  10. Toxicity of the pesticide alpha-cypermethrin to four soil nontarget invertebrates and implications for risk assessment.

    Science.gov (United States)

    Hartnik, Thomas; Sverdrup, Line E; Jensen, John

    2008-06-01

    Alpha-cypermethrin, a synthetic pyrethroid, is used as an insecticide in agricultural settings and is increasingly replacing organophosphates and carbamates because of lower application rates and lower toxicity to mammals. Because very little is known about the acute and chronic toxicity of this compound for soil-living organisms, the present study investigated acute and sublethal toxicity of alpha-cypermethrin for four terrestrial invertebrate species in an agricultural soil from Norway. Bioassays with the earthworm Eisenia fetida, the potworm Enchytraeus crypticus, the springtail Folsomia candida, and the land snail Helix aspersa were performed according to slightly modified versions of Organization for Economic Cooperation and Development (Paris, France) or International Organization for Standardization (Geneva, Switzerland) guidelines and resulted in median lethal concentrations of greater than >1,000 to 31.4 mg/kg and sublethal no-observed-effect concentrations of 2.51 to 82 mg/kg. A high acute to chronic ratio was found, especially in the earthworms. Interspecies differences in sensitivity may be explained by differences in exposure and differences in metabolization rate. When based on measured pore-water concentrations, terrestrial species overall appear to be approximately one order of magnitude less sensitive than aquatic species. Effect assessments conducted according to European guideline for risk assessment of pesticides reveal that assessments based on acute toxicity tests are not always conservative enough to determine environmentally safe concentrations in soil. Mandatory incorporation of sublethal toxicity data will ensure that in regions with temperate climate, the effects of pesticides on populations of soil-living organisms are unlikely.

  11. Selection of a bioassay battery to assess toxicity in the affluents and effluents of three water-treatment plants

    Directory of Open Access Journals (Sweden)

    Paola Bohórquez-Echeverry

    2012-08-01

    Full Text Available The assessment of water quality includes the analysis of both physical-chemical and microbiological parameters. However,none of these evaluates the biological effect that can be generated in ecosystems or humans. In order to define the most suitable organismsto evaluate the toxicity in the affluent and effluent of three drinking-water treatment plants, five acute toxicity bioassays were used,incorporating three taxonomic groups of the food chain. Materials and methods. The bioassays used were Daphnia magna and Hydraattenuata as animal models, Lactuca sativa and Pseudokirchneriella subcapitata as plant models, and Photobacterium leioghnathi asbacterial model. To meet this objective, selection criteria of the organisms evaluated and cluster analysis were used to identify the mostsensitive in the affluent and effluent of each plant. Results. All organisms are potentially useful in the assessment of water quality bymeeting four essential requirements and 17 desirable requirements equivalent to 100% acceptability, except P. leioghnathi which doesnot meet two essential requirements that are the IC50 for the toxic reference and the confidence interval. The animal, plant and bacterialmodels showed different levels of sensitivity at the entrance and exit of the water treatment systems. Conclusions. H. attenuata, P.subcapitata and P. leioghnathi were the most effective organisms in detecting toxicity levels in the affluents and D. magna, P. subcapitataand P. leioghnathi in the effluents.

  12. Acute toxicity and risk assessment of permethrin, naled, and dichlorvos to larval butterflies via ingestion of contaminated foliage.

    Science.gov (United States)

    Hoang, Tham C; Rand, Gary M

    2015-02-01

    Three Florida native larval butterflies (Junonia coenia, Anartia jatrophae, Eumaeus atala) were used in the present study to determine the acute toxicity, hazard, and risk of a 24h ingestion of leaves contaminated with the adult mosquito control insecticides permethrin, naled, and dichlorvos to late 4th and early 5th in-star caterpillars. Based on 24-h LD50s for ingestion, naled was more acutely toxic than permethrin and dichlorvos to caterpillars. Hazard quotients using the ratio of the highest doses and the 90th percentile doses from field measurements in host plant foliage following actual mosquito control applications to the toxicological benchmarks from laboratory toxicity tests indicate potential high acute hazard for naled compared to permethrin and dichlorvos. Based on probabilistic ecological risk methods, naled exposure doses in the environment also presented a higher acute risk to caterpillars than permethrin and dichlorvos. The acute toxicity laboratory results and ecological risk assessment are based only on dietary ingestion and single chemical doses. It does not include other typical exposure scenarios that may occur in the environment. It is thus plausible to state that the ecological risk assessment presented here underestimates the potential risks in the field to caterpillars. However, one assumption that is scientifically feasible and certainly real from the results - if the environmental exposure doses of mosquito control operations are similar or higher to those presented here in leaves from the field, after applications, there will likely be significant mortalities and other adverse effects on caterpillar populations. PMID:25462317

  13. Establishing a Th17 based mouse model for preclinical assessment of the toxicity of candidate microbicides

    Institute of Scientific and Technical Information of China (English)

    LI Liang-zhu; YANG Yu; YUAN Song-hua; WAN Yan-min; QIU Chao; FENG Yan-ling; XU Jian-qing; ZHANG Xiao-yan

    2010-01-01

    Background To effectively block the invasion of human immunodeficiency virus (HIV)-1 on mucosal surface, vaginal anti-HIV-1 microbicides should avoid inflammatory responses and disruption of mucosa integrity because these will facilitate transepithelial viral penetration and replication. However, existing models fail to predict and evaluate vaginal mucosal toxicity induced by microbicides, and most importantly, they are unable to identify subtle or subclinical inflammatory reactions. This study was designed to develop a cost-effective in vivo model to evaluate microbicide safety in a preclinical study which can recapitulate the mucosal topical reaction.Methods A murine model was employed with nonoxynol-9 (N-9) as the topical stimulant within the vagina. Different concentrations of N-9 (1%, 3%, and 4%) were topically applied to the vagina for five consecutive days. A panel of inflammatory cytokines including interleukine-2 (IL-2), IL-4, IL-6, IL-17A, interferon-Y (IFN-Y), tumor necrosis factor-α (TNF-α), and immuno-regulatory IL-10 were assayed in vaginal lavage. Cytokines were quantified by using cytometric bead array (CBA) and reverse transcript (RT) real-time PCR. Histopathological evaluation of vaginal tissues was conducted on hematoxylin-eosin stained slides and scored with a semi-quantitative system according to the severity of epithelial disruption, leucocyte infiltration, edema, and vascular injection. The association between the cytokines and histopathological scores was assessed by linear regression analysis.Results All three concentrations of N-9 induced inflammatory cytokine production. The 4% N-9 application resulted in a consistent production of cytokines in a time-dependent manner. The cytokines reached peak expression on day three with the exception of IL-4 which reached its peak on day one. Histopathological examination of 4% N-9 treated cervicovaginal tissues on day three showed intensive damage in four mice (sores: 10-13) and moderate damage in

  14. Detection of microcystins in Pamvotis lake water and assessment of cyanobacterial bloom toxicity.

    Science.gov (United States)

    Papadimitriou, Theodoti; Armeni, Euthimia; Stalikas, Constantine D; Kagalou, Ifigeneia; Leonardos, Ioannis D

    2012-05-01

    Lake Pamvotis is a shallow, eutrophic Mediterranean lake with ecological significance. This paper deals with the evaluation of cyanobacterial toxicity in Lake Pamvotis. ELISA and HPLC revealed the presence of significant amounts of MCYST-LR. Danio rerio bioassay confirmed the toxic nature of the bloom. Cyanobacterial extracts had adverse toxic effects on development of D. rerio. Also, it was shown that cyanobacterial extracts containing environmentally detected concentrations of MCYST can cause reduced survival rate of fish species. The results clearly indicate that cyanobacterial blooms in Lake Pamvotis may be regarded as human and fish health hazard. Continuous monitoring of the lake is suggested, in order to prevent future possible intoxications. PMID:21713485

  15. Assessment of anthropogenic vegetation productivity decline in the Volta basin from 1982 to 2003

    Science.gov (United States)

    Vlek, Quang Bao Le, Lulseged Tamene, Paul L. G.

    2009-04-01

    Primary productivity decline is causing loss of ecosystem services which in turn influences not only the water cycle, but also the livelihoods of millions of inhabitants worldwide. Climate change or other natural events may be responsible for land degradation, but the phenomenon is mainly due to human actions. Therefore, it would be important to identify those areas in which the pressure on land needs to be alleviated. In this study, we conducted a step-wise analysis using a series of databases to identify the extent of land under anthropogenic threats. We processed time-series NDVI (Normalized Difference Vegetation Index) products for the period 1982 - 2003 to analyse long-term trends in biomass productivity changes over the Volta basin. To distinguish human-induced biomass trends from climate-driven vegetation dynamics, we excluded those areas that had shown a strong biomass response to inter-annual rainfall variation. Pixels with NDVI changes in accordance with rainfall (positive correlation) were considered due to climate change or variation. Pixels not affected by rainfall (no or negative correlation) are those where green biomass change could be interpreted to reflect areas with strictly human induced land degradation. Spatial data of soil constraints, land-use/cover and population density within the study period were used to interpret possible underlying factors of land productivity decline. The results of the study show that about 31 thousands km2 (8% of the basin land mass), which is the living space of over 1.3 million people, was land that is losing its ability to produce green biomass due to human actions. The degradation areas for the various land cover types are 12.2 thousands km2 for woodland, 8.3 thousands km2 for agriculture, 7.3 thousands km2 for shrubland, and 1.6 thousands km2 for evergreen forest. The relatively low population density in the degraded areas (averagely 43 pers.km-2) would suggest that these are marginal areas with limited

  16. Trichloroethylene: mechanisms of renal toxicity and renal cancer and relevance to risk assessment.

    Science.gov (United States)

    Lock, Edward A; Reed, Celia J

    2006-06-01

    1,1,2-Trichloroethylene (TCE) is an important solvent that is widespread in the environment. We have reviewed carcinogenicity data from seven bioassays with regard to renal injury and renal tumors. We report a consistent but low incidence of renal tubule carcinoma in male rats. Epidemiology studies on workers exposed to TCE (and other chlorinated solvents) indicate a weak association between high-level exposure and renal cancer. There appears to be a threshold below which no renal injury or carcinogenicity is expected to arise. TCE is not acutely nephrotoxic to rats or mice, but subchronic exposure to rats produces a small increase in urinary markers of renal injury. Following chronic exposure, pathological changes (toxic nephrosis and a high incidence of cytomegaly and karyomegaly) were observed. The basis for the chronic renal injury probably involves bioactivation of TCE. Based on the classification by E. A. Lock and G. C. Hard (2004, Crit. Rev. Toxicol. 34, 211-299) of chemicals that induce renal tubule tumors, we found no clear evidence to place TCE in category 1 or 2 (chemicals that directly or indirectly interact with renal DNA), category 4 (direct cytotoxicity and sustained tubule cell regeneration), category 5 (indirect cytotoxicity and sustained tubule cell regeneration associated with alpha2u-globulin accumulation), or category 6 (exacerbation of spontaneous chronic progressive nephropathy). TCE is best placed in category 3, chemicals that undergo conjugation with GSH and subsequent enzymatic activation to a reactive species. The implication for human risk assessment is that TCE should not automatically be judged by linear default methods; benchmark methodology could be used.

  17. Isotopically modified silver nanoparticles to assess nanosilver bioavailability and toxicity at environmentally relevant exposures

    Science.gov (United States)

    Croteau, Marie-Noële; Dybowska, Agnieszka D.; Luoma, Samuel N.; Misra, Superb K.; Valsami-Jones, Eugenia

    2014-01-01

    A major challenge in understanding the environmental implications of nanotechnology lies in studying nanoparticle uptake in organisms at environmentally realistic exposure concentrations. Typically, high exposure concentrations are needed to trigger measurable effects and to detect accumulation above background. But application of tracer techniques can overcome these limitations. Here we synthesised, for the first time, citrate-coated Ag nanoparticles using Ag that was 99.7 % 109Ag. In addition to conducting reactivity and dissolution studies, we assessed the bioavailability and toxicity of these isotopically modified Ag nanoparticles (109Ag NPs) to a freshwater snail under conditions typical of nature. We showed that accumulation of 109Ag from 109Ag NPs is detectable in the tissues of Lymnaea stagnalis after 24-h exposure to aqueous concentrations as low as 6 ng L–1 as well as after 3 h of dietary exposure to concentrations as low as 0.07 μg g–1. Silver uptake from unlabelled Ag NPs would not have been detected under similar exposure conditions. Uptake rates of 109Ag from 109Ag NPs mixed with food or dispersed in water were largely linear over a wide range of concentrations. Particle dissolution was most important at low waterborne concentrations. We estimated that 70 % of the bioaccumulated 109Ag concentration in L. stagnalis at exposures –1 originated from the newly solubilised Ag. Above this concentration, we predicted that 80 % of the bioaccumulated 109Ag concentration originated from the 109Ag NPs. It was not clear if agglomeration had a major influence on uptake rates.

  18. Formulation Development and Toxicity Assessment of Triacetin Mediated Nanoemulsions as Novel Delivery Systems for Rapamycin

    Science.gov (United States)

    Sobhani, Hamideh; Tarighi, Parastoo; Ostad, Seyed Nasser; Shafaati, Alireza; Nafissi-Varcheh, Nastaran; Aboofazeli, Reza

    2015-01-01

    The aim of this investigation was to design and develop nanoemulsions (NEs) as novel delivery systems for rapamycin. Phase behavior of quaternary systems composed of Traicetin (as oil), various surfactants and co-surfactants and water at different surfactant/co-surfactant weight ratios was investigated by the construction of phase diagrams. Formulations were taken from the o/w NE region of the phase diagrams, depending upon the extent of NE domain. The spontaneous emulsification method was used to prepare various formulations containing 1 mg/mL of the drug. The NEs were characterized and subjected to stability tests at various temperatures over 9-12 months. Cumulative drug release from the selected formulations was determined for a period of 48 h using a dialysis sac. The assay of rapamycin was carried out using an HPLC technique. The effect of NEs on the viability of SKBR-3 cells was evaluated by MTT assay. The integrity of Caco-2 cell monolayers was measured by Transepithelial Electrical Resistance (TEER) and the transport of rapamycin-loaded NEs across Caco-2 cell monolayers was then assessed. The uptake of NEs by SKBR-3 cells was also investigated using florescence microscopy. Maximum drug release was observed in case of 4 formulations prepared with Tween 80 and Tween 20. MTT test results revealed different toxicity of NEs for SKBR-3 cell line and TEER demonstrated that formulations containing Tween 20 caused a more considerable decrease in cell integrity in comparison with those prepared with Tween 80. The results obtained from cellular uptake experiments were in consistent with those obtained from TEER and cytotoxicity experiments. PMID:26185501

  19. Toxic Risk Assessment of Arsenic in Males Through Drinking Water in Tharparkar Region of Sindh, Pakistan.

    Science.gov (United States)

    Brahman, Kapil Dev; Kazi, Tasneem Gul; Afridi, Hassan Imran; Arain, Sadaf Sadia; Kazi, Atif Gul; Talpur, Farah Naz; Baig, Jameel Ahmed; Panhwar, Abdul Haleem; Arain, Mariam Shezadi; Ali, Jamshed; Arain, Mohammad Balal; Naeemullah

    2016-07-01

    Humans are exposed to arsenic (As) through air, drinking water, and food. The arsenic (As) hazardous quotient was calculated on the basis of its concentration in drinking water of different origin and scalp hair of male subjects (n = 313), residents of different exposed and non-exposed areas of Sindh, Pakistan. The total As was determined in water and scalp hair samples, while As species were determined in water samples by advance extraction methodologies. The total As concentrations in drinking water of less-exposed (LE) and high-exposed (HE) areas was found to be 2.63 to 4.46 and 52 to 235, fold higher than the permissible limit, respectively, than recommended by World Health Organization (2004) for drinking water. While the levels of As in drinking water of non-exposed (NE) areas was within the permissible limit. The resulted data indicated that the dominant species was As(+5) in groundwater samples. The levels of As in scalp hair samples of male subjects of two age groups (18-30 and 31-50 years), belonging to NE, LE, and HE areas, ranged from 0.26 to 0.69, 0.58 to 1.34, and 15.6 to 60.9 μg/g, respectively. A significant correlation between As levels in drinking water and scalp hair was observed in HE area (r = 0.86-0.90, p < 0.001) as compared to those subjects belonging to LE area. A toxicity risk assessment was calculated as hazard quotient (HQ), which indicates that the study subjects of HE area have significantly higher values of HQ than LE. The population of As exposed areas is at high risk of non-carcinogenic and carcinogenesis effects. PMID:26606915

  20. Field Plot and Accuracy Assessment Points for Ozark National Scenic Riverways Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Accuracy Assessment, Observation and Plot Points. This data set includes points used to collect data for map valdiation of community types in Ozark National Scenic...

  1. Field Plot and Accuracy Assessment Points for Palo Alto Battlefield National Historical Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Accuracy Assessment, Observation and Plot Points. Plot data were collected from 2000-2003; however, minimal attributes were maintained and a plots database was not...

  2. Field Plot and Accuracy Assessment Points for Bent's Old Fort National Historic Site Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Accuracy Assessment, Observation and Plot Points. Plots within the park were identified and sampled in the summer of 2005. In the summer of 2006, randomly selected...

  3. Accuracy Assessment Points for Canyon De Chelly National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The Canyon de Chelly National Monument Accuracy Assessment Observation Location executable shapefile (cachaa.exe) was developed as a Geographic Information Systems...

  4. Accuracy Assessment Points for Washita Battlefield National Historic Site Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the 2006 accuracy assessment points (spatial database) created from the sample points collected at Washita Battlefield National Historic Site.

  5. Accuracy Assessment Points for Petrified Forest National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The Petrified Forest National Park Accuracy Assessment Observation Location zip shapefile (pefoaa.zip) was developed as a Geographic Information Systems (GIS)...

  6. Field Plot and Accuracy Assessment Points for Hagerman Fossil Beds National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Accuracy Assessment, Observation and Plot Points. Plot points were created from the GPS coordinates recorded at the center of each plot to map their distribution...

  7. Field Plot and Accuracy Assessment Points for Padre Island National Seashore Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Accuracy Assessment, Observation and Plot Points. Currently there are NO DATA in this feature class. As of December 2009, a plots database has not been developed...

  8. Accuracy Assessment Points for San Antonio Missions National Historical Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the 2006 accuracy assessment points (spatial database) created from the sample points collected at San Antonio Missions National Historical Park.

  9. Accuracy Assessment Points for Craters of the Moon National Monument and Preserve Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the 2008 accuracy assessment points (spatial database) created from the sample points collected at Craters of the Moon National Monument and...

  10. 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.

  11. Acute Toxicity Assessment of Reactive Red 120 to Certain Aquatic Organisms.

    Science.gov (United States)

    Darsana, R; Chandrasehar, G; Deepa, V; Gowthami, Y; Chitrikha, T; Ayyappan, S; Goparaju, A

    2015-11-01

    Laboratory experiments were conducted to evaluate the acute toxicity of a widely used textile dye namely Reactive Red 120 (RR 120) on certain aquatic species such as Pseudokirchneriella subcapitata (green alga), Lemna gibba (duck weed), Daphnia magna (water flea) and Oncorhynchus mykiss (Rainbow trout). All experiments were performed as per the OECD Guidelines for Testing of Chemicals. The toxicity end points of EC50, LC50, NOEC and LOEC for RR 120 were determined with 95% confidence limits using TOX STAT version 3.5. The EC50 of RR 120 for green alga, duck weed and water flea are >100.00, 64.34, 10.40 mg L(-1), respectively and LC50 for Rainbow trout is 78.84 mg L(-1). Based on the results, the test item RR 120 could be classified as non-toxic to green alga, harmful to duck weed and Rainbow trout, toxic to water flea. PMID:26350898

  12. Photosynthesis tests as an alternative to growth tests for hazard assessment of toxicant

    DEFF Research Database (Denmark)

    Petersen, S.; Kusk, Kresten Ole

    2000-01-01

    Acute (3- and 6-h) toxic responses toward Cu, linear alkylbenzene sulfonate (LAS), and tributyltin (TBT) of lightsaturated and unsaturated photosynthesis were investigated for Rhodomonas salina and Skeletonema costatum obtained from exponentially growing batch cultures and from chemostat cultures...

  13. Post-disposal safety assessment of toxic and radioactive waste: waste types, disposal practices, disposal criteria, assessment methods and post-disposal impacts

    International Nuclear Information System (INIS)

    The need for safety assessments of waste disposal stems not only from the implementation of regulations requiring the assessment of environmental effects, but also from the more general need to justify decisions on protection requirements. As waste-disposal methods have become more technologically based, through the application of more highly engineered design concepts and through more rigorous and specific limitations on the types and quantities of the waste disposed, it follows that assessment procedures also must become more sophisticated. It is the overall aim of this study to improve the predictive modelling capacity for post-disposal safety assessments of land-based disposal facilities through the development and testing of a comprehensive, yet practicable, assessment framework. This report records all the work which has been undertaken during Phase 1 of the study. Waste types, disposal practices, disposal criteria and assessment methods for both toxic and radioactive waste are reviewed with the purpose of identifying those features relevant to assessment methodology development. Difference and similarities in waste types, disposal practices, criteria and assessment methods between countries, and between toxic and radioactive wastes are highlighted and discussed. Finally, an approach to identify post-disposal impacts, how they arise and their effects on humans and the environment is described

  14. Assessing uncertainties in a second-generation dynamic vegetation model caused by ecological scale limitations.

    Science.gov (United States)

    Fisher, Rosie; McDowell, Nate; Purves, Drew; Moorcroft, Paul; Sitch, Stephen; Cox, Peter; Huntingford, Chris; Meir, Patrick; Woodward, F Ian

    2010-08-01

    *Second-generation Dynamic Global Vegetation Models (DGVMs) have recently been developed that explicitly represent the ecological dynamics of disturbance, vertical competition for light, and succession. Here, we introduce a modified second-generation DGVM and examine how the representation of demographic processes operating at two-dimensional spatial scales not represented by these models can influence predicted community structure, and responses of ecosystems to climate change. *The key demographic processes we investigated were seed advection, seed mixing, sapling survival, competitive exclusion and plant mortality. We varied these parameters in the context of a simulated Amazon rainforest ecosystem containing seven plant functional types (PFTs) that varied along a trade-off surface between growth and the risk of starvation induced mortality. *Varying the five unconstrained parameters generated community structures ranging from monocultures to equal co-dominance of the seven PFTs. When exposed to a climate change scenario, the competing impacts of CO(2) fertilization and increasing plant mortality caused ecosystem biomass to diverge substantially between simulations, with mid-21st century biomass predictions ranging from 1.5 to 27.0 kg C m(-2). *Filtering the results using contemporary observation ranges of biomass, leaf area index (LAI), gross primary productivity (GPP) and net primary productivity (NPP) did not substantially constrain the potential outcomes. We conclude that demographic processes represent a large source of uncertainty in DGVM predictions. PMID:20618912

  15. Toxicity-based assessment of the treatment performance of wastewater treatment and reclamation processes

    Institute of Scientific and Technical Information of China (English)

    Dongbin Wei; Zhuowei Tan; Yuguo Du

    2012-01-01

    The reclamation and reuse of wastewater is one of the possible ways to relieve the serious fresh water resource crisis in China.Efficient reclamation treatment technologies ensure the safe reuse of reclaimed water.In order to screen out and evaluate technologies appropriate for reclamation treatment,a great deal of efforts have been brought to bear.In the present study,a toxicity-based method including a Photobacterium phosphorewn test for acute toxicity and SOS/umu test for genotoxicity,accompanied by the traditional physicochemical parameters DOC (dissolved organic carbon) and UV254 (absorbance at 254 nm),was used to measure the treatment performance of different reclamation processes,including the anaerobic-anoxic-oxic biological process (A2O) and subsequent physical/chemical reclamation processes (ultrafiltration,ozonation,chlorination).It was found that for the secondary effluent after the A2O process,both the toxicity and physicochemical indices had greatly decreased compared with those of the influent.However,chemical reclamation processes such as ozonation and chlorination could possibly raise toxicity levels again.Fortunately,the toxicity elevation could be avoided by optimizing the ozone dosage and using activated carbon after ozonation.It was noted that by increasing the ozone dosage to 10 mg/L and employing activated carbon with more than 10 min hydraulic retention time,toxicity elevation was controlled.Furthermore,it was shown that pre-ozonation before activated carbon and chlorination played an important role in removing organic compounds and reducing the toxicity formation potential.The toxicity test could serve as a valuable tool to evaluate the performance of reclamation processes.

  16. Bacterial toxicity assessment of drinking water treatment residue (DWTR) and lake sediment amended with DWTR.

    Science.gov (United States)

    Yuan, Nannan; Wang, Changhui; Pei, Yuansheng

    2016-11-01

    Drinking water treatment residue (DWTR) seems to be very promising for controlling lake sediment pollution. Logically, acquisition of the potential toxicity of DWTR will be beneficial for its applications. In this study, the toxicity of DWTR and sediments amended with DWTR to Aliivibrio fischeri was evaluated based on the Microtox(®) solid and leachate phase assays, in combination with flow cytometry analyses and the kinetic luminescent bacteria test. The results showed that both solid particles and aqueous/organic extracts of DWTR exhibited no toxicity to the bacterial luminescence and growth. The solid particles of DWTR even promoted bacterial luminescence, possibly because DWTR particles could act as a microbial carrier and provide nutrients for bacteria growth. Bacterial toxicity (either luminescence or growth) was observed from the solid phase and aqueous/organic extracts of sediments with or without DWTR addition. Further analysis showed that the solid phase toxicity was determined to be related mainly to the fixation of bacteria to fine particles and/or organic matter, and all of the observed inhibition resulting from aqueous/organic extracts was identified as non-significant. Moreover, DWTR addition not only had no adverse effect on the aqueous/organic extract toxicity of the sediment but also reduced the solid phase toxicity of the sediment. Overall, in practical application, the solid particles, the water-soluble substances transferred to surface water or the organic substances in DWTR had no toxicity or any delayed effect on bacteria in lakes, and DWTR can therefore be considered as a non-hazardous material. PMID:27454093

  17. Determination of 210Po in leafy vegetables and annual effective dose assessment to the inhabitants of Mumbai city, India

    International Nuclear Information System (INIS)

    Present study deals with the measurement of activity concentration of 210Po in leafy vegetable of Mumbai city and corresponding ingestion dose assessment to the population. 210Po activity levels ranged from 44.5-183.3 with an average value of 81.8 mBq/kg. Minimum activity of 210Po was found in shepu and maximum in methi. The concentration reported here is slightly more than the UNSCEAR value. The estimated total effective dose was found to vary from 0.3 - 1.4 with an average value of 0.6 μSv/y, which is about 1% of global average total ingestion dose due to 210Po. (author)

  18. Lentic wetland inventory, health assessment, and vegetation mapping of the Benton Lake National Wildlife Refuge, central Montana [draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The objective of this study is to characterize and quantify the wetland vegetation present on Benton Lake NWR in terms of individual species, as well as vegetation...

  19. Assessment of farmers’ knowledge on fertilizer usage for peri-urban vegetable production in the Sunyani Municipality, Ghana

    DEFF Research Database (Denmark)

    Obour, Peter Bilson; Dadzie, Frederick Asankom; Kristensen, Hanne Lakkenborg;

    2015-01-01

    farmers’ knowledge on fertilizer usage for intensive vegetable production in peri-urban areas in Ghana where production and marketing of vegetables cause significant export of nutrients from farms. Data were collected from 180 peri-urban vegetable growers in Abesim and Yawhima in the Sunyani Municipality...

  20. Herbicide toxicity on river biofilms assessed by pulse amplitude modulated (PAM) fluorometry

    Energy Technology Data Exchange (ETDEWEB)

    Kim Tiam, Sandra, E-mail: sandra.kimtiam@gmail.com [Irstea, UR EABX, 50 Avenue de Verdun, F-33612, Cestas Cedex (France); Université de Bordeaux, EPOC, UMR 5805, F-33120 Arcachon (France); Laviale, Martin [Departamento de Biologia and CESAM – Centro de Estudos do Ambiente e do Mar Universidade de Aveiro, Campus de Santiago, 3810-193 Aveiro (Portugal); Sorbonne Universités, UPMC Univ Paris 06, UMR 7093, LOV, Observatoire Océanologique, F-06230, Villefranche-Sur-Mer (France); CNRS, UMR 7093, LOV, Observatoire Océanologique, F-06230, Villefranche-Sur-Mer France (France); Feurtet-Mazel, Agnès [Université de Bordeaux, EPOC, UMR 5805, F-33120 Arcachon (France); Jan, Gwilherm [Irstea, UR EABX, 50 Avenue de Verdun, F-33612, Cestas Cedex (France); Gonzalez, Patrice [Université de Bordeaux, EPOC, UMR 5805, F-33120 Arcachon (France); Mazzella, Nicolas; Morin, Soizic [Irstea, UR EABX, 50 Avenue de Verdun, F-33612, Cestas Cedex (France)

    2015-08-15

    Highlights: • Rapid Light Curves were shown to be early markers of toxicant exposure. • Diuron and norflurazon effects were significant at environmentally realistic concentrations. • Toxic effects in intact biofilms seem to be delayed compared to disrupted biofilms. - Abstract: The use of Rapid light curves (RLCs) as a toxicity endpoint for river biofilms was examined in this study and compared to “classical fluorescence parameters” i.e. minimal fluorescence (F{sub 0}), optimal and effective quantum yields of photosystem II (F{sub v}/F{sub m} and Φ{sub PSII}). Measurements were performed after exposure to five concentrations of diuron (from 0.3 to 33.4 μg L{sup −1}), its main degradation product (DCPMU) (from 1.0 to 1014 μg L{sup −1}) and norflurazon (from 0.6 to 585 μg L{sup −1}) with the lowest exposure concentrations corresponding to levels regularly encountered in chronically contaminated sites. Biofilm responses were evaluated after 1, 5, 7 and 14 days of exposure to the different toxicants. Overall, the responses of both “classical fluorescence parameters” and RLC endpoints were highly time dependent and related to the mode of action of the different compounds. Interestingly, parameters calculated from RLCs (α, ETR{sub max} and I{sub k}) were useful early markers of pesticide exposure since they revealed significant effects of all the tested toxicants from the first day of exposure. In comparison, classical fluorescence endpoints (F{sub 0} and F{sub v}/F{sub m}) measured at day 1 were only affected in the DCPMU treatment. Our results demonstrated the interest of RLCs as early markers of toxicant exposure particularly when working with toxicants with less specific mode of action than PSII inhibitors.

  1. Sources of errors in assessing ozone visible symptoms on native vegetation

    International Nuclear Information System (INIS)

    This paper aims to identify the problems regarding the evaluation of ozone (and ozone-like) symptoms, by examining the results of the 4th UN/ECE ICP-Forests Intercalibration Course for the assessment of ozone-induced visible symptoms. Trees, shrubs and herbaceous species were evaluated in a tree nursery, at Lattecaldo (Switzerland) and under open field conditions at Moggio (Italy). The main findings were: (i) the most expert surveyors tended to be grouped in the same cluster and, during the field exercises, they tended to assess in a more conservative manner compared to the less trained participants; (ii) the agreement was greater in assessing the absence rather than the presence of symptoms; (iii) typical interveinal stippling on the upper leaf surface was more accurately evaluated than discoloration; (iv) uncertainties resulted mainly for species which showed greater variability in their symptom manifestation, and for certain herbaceous species. - The quality of foliar ozone-symptom assessment depends on the experience of the surveyor, the symptom specificity, and the symptom variability within the same species

  2. Environmental toxicity and radioactivity assessment of a titanium-processing residue with potential for environmental use.

    Science.gov (United States)

    Wendling, Laura A; Binet, Monique T; Yuan, Zheng; Gissi, Francesca; Koppel, Darren J; Adams, Merrin S

    2013-07-01

    Thorough examination of the physicochemical characteristics of a Ti-processing residue was undertaken, including mineralogical, geochemical, and radiochemical characterization, and an investigation of the environmental toxicity of soft-water leachate generated from the residue. Concentrations of most metals measured in the leachate were low; thus, the residue is unlikely to leach high levels of potentially toxic elements on exposure to low-ionic strength natural waters. Relative to stringent ecosystem health-based guidelines, only chromium concentrations in the leachate exceeded guideline concentrations for 95% species protection; however, sulfate was present at concentrations known to cause toxicity. It is likely that the high concentration of calcium and extreme water hardness of the leachate reduced the bioavailability of some elements. Geochemical modeling of the leachate indicated that calcium and sulfate concentrations were largely controlled by gypsum mineral dissolution. The leachate was not toxic to the microalga Chlorella sp., the cladoceran Ceriodaphnia dubia, or the estuarine bacterium Vibrio fischeri. The Ti-processing residue exhibited an absorbed dose rate of 186 nGy/h, equivalent to an annual dose of 1.63 mGy and an annual effective dose of 0.326 mGy. In summary, the results indicate that the Ti-processing residue examined is suitable for productive use as an environmental amendment following 10 to 100 times dilution to ameliorate potential toxic effects due to chromium or sulfate.

  3. The importance of experimental time when assessing the effect of temperature on toxicity in poikilotherms.

    Science.gov (United States)

    Nørhave, Nils J; Spurgeon, David; Svendsen, Claus; Cedergreen, Nina

    2014-06-01

    Temperature is an important factor affecting toxicity, determining chemical toxicokinetics and toxicodynamics in poikilothermic organisms. Because metabolic rates are also affected by temperature, interactions between the emergence of toxic effects and time are very likely. The aim of the present study was to investigate how temperature affects the toxicity of copper toward the nematode Caenorhabditis elegans when measured during short, fixed time frames compared with full life cycles. Copper toxicity was tested in 2 experiments at 4 or 6 temperatures in the range of 11 °C to 24 °C, with Cu concentrations spanning from 1 mg Cu/L agar to 40 mg Cu/L agar, respectively. Reproduction and mortality were determined across the entire life cycle, and the time to production of first egg and the population growth rate were calculated. The results showed that the 50% effect concentrations (EC50s) of Cu increased 1.5-fold to 2.5-fold with increasing temperature within the tested range, depending on endpoint. When calculating EC50 on reproduction after 24 h or 96 h, the typical setup for temperature-chemical interaction studies, results ranged from no temperature effect to effects much larger than those for the full life cycle. Studies of temperature effects on toxicity must therefore be carefully designed in relation to the research question being investigated. PMID:24648200

  4. Food safety and risk assessment: naturally occurring potential toxicants and anti-nutritive compounds in plant foods.

    Science.gov (United States)

    Sanders, Thomas A B

    2003-01-01

    The centralisation and globalisation of the world food supply presents opportunities for massive epidemics of food borne illness. Food processing generally decreases exposure to naturally occurring toxicants. A significant number of deaths are caused in both developed and developing countries from the consumption of naturally occurring toxicants and this exceeds the numbers attributable to artificial food contaminants and pollutants. The risk posed by naturally occurring toxicants is greater in developing countries where food choice and facilities for food processing are limited. The main risk in developed countries is from food important from areas where food safety controls are inadequate. Toxins derived from marine algae present a specific threat to health especially as seafood is being traded from areas where poisoning by algal toxins is known to occur. A systematic approach to food safety using HACCP methodology and identity preservation of the food are crucial in the prevention of food related illness. There is also a need for international agreed standards for tolerable levels of naturally occurring toxicants in foodstuffs but these should derived not be set unreasonably low as this would threaten food security in developing countries. The occurrence of a number of fatalities in developing countries among people consuming herbal teas and dietary supplements underscores the need to assess the safety of these products before they are placed on the market. PMID:15806954

  5. Assessment of digital camera-derived vegetation indices in quantitative monitoring of seasonal rice growth

    Science.gov (United States)

    Sakamoto, Toshihiro; Shibayama, Michio; Kimura, Akihiko; Takada, Eiji

    2011-11-01

    A commercially available digital camera can be used in a low-cost automatic observation system for monitoring crop growth change in open-air fields. We developed a prototype Crop Phenology Recording System (CPRS) for monitoring rice growth, but the ready-made waterproof cases that we used produced shadows on the images. After modifying the waterproof cases, we repeated the fixed-point camera observations to clarify questions regarding digital camera-derived vegetation indices (VIs), namely, the visible atmospherically resistant index (VARI) based on daytime normal color images (RGB image) and the nighttime relative brightness index (NRBI NIR) based on nighttime near infrared (NIR) images. We also took frequent measurements of agronomic data such as plant length, leaf area index (LAI), and aboveground dry matter weight to gain a detailed understanding of the temporal relationship between the VIs and the biophysical parameters of rice. In addition, we conducted another nighttime outdoor experiment to establish the link between NRBI NIR and camera-to-object distance. The study produced the following findings. (1) The customized waterproof cases succeeded in preventing large shadows from being cast, especially on nighttime images, and it was confirmed that the brightness of the nighttime NIR images had spatial heterogeneity when a point light source (flashlight) was used, in contrast to the daytime RGB images. (2) The additional experiment using a forklift showed that both the ISO sensitivity and the calibrated digital number of the NIR (cDN NIR) had significant effects on the sensitivity of NRBI NIR to the camera-to-object distance. (3) Detailed measurements of a reproductive stem were collected to investigate the connection between the morphological feature change caused by the panicle sagging process and the downtrend in NRBI NIR during the reproductive stages. However, these agronomic data were not completely in accord with NRBI NIR in terms of the temporal pattern

  6. USEtox - The UNEP-SETAC toxicity model: recommended characterisation factors for human toxicity and freshwater ecotoxicity in Life Cycle Impact Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Rosenbaum, Ralph K.; Bachmann, Till M.; Swirsky Gold, Lois; Huijbregts, Mark A.J.; Jolliet, Olivier; Juraske, Ronnie; Koehler, Annette; Larsen, Henrik F.; MacLeod, Matthew; Margni, Manuele; McKone, Thomas E.; Payet, Jerome; Schuhmacher, Marta; van de Meent, Dik; Hauschild, Michael Z.

    2008-02-03

    .Conclusions. USEtox provides a parsimonious and transparent tool for human health and ecosystem CF estimates. Based on a referenced database, it has now been used to calculate CFs for several thousand substances and forms the basis of the recommendations from UNEP-SETAC's Life Cycle Initiative regarding characterization of toxic impacts in Life Cycle Assessment. Recommendations and Perspectives. We provide both recommended and interim (not recommended and to be used with caution) characterisation factors for human health and freshwater ecotoxicity impacts. After a process of consensus building among stakeholders on a broad scale as well as several improvements regarding a wider and easier applicability of the model, USEtox will become available to practitioners for the calculation of further CFs.

  7. Assessment of antioxidant, anticancer and antimicrobial activity of two vegetable species of Amaranthus in Bangladesh

    OpenAIRE

    Al-Mamun, M. Abdulla; Husna, Jamiatul; Khatun, Masuda; Hasan, Rubait; Kamruzzaman, M.; Hoque, K. M. F.; Reza, M. Abu; Ferdousi, Z.

    2016-01-01

    Background Amaranthus (Amaranthaceae) has previously been reported to possess different bioactive phytochemicals including phenols, tannins and flavonoids. The current study was designed to evaluate the antioxidant, anti-proliferative and antimicrobial activity of stem and seed extracts of Amaranthus lividus (AL) and Amaranthus hybridus (AH), respectively. Methods Antioxidant activity of methanol extract was assessed by DPPH radical scavenging assay. Determination of lectin activity of Amaran...

  8. Toxicity assessment strategies, data requirements, and risk assessment approaches to derive health based guidance values for non-relevant metabolites of plant protection products.

    Science.gov (United States)

    Dekant, Wolfgang; Melching-Kollmuss, Stephanie; Kalberlah, Fritz

    2010-03-01

    In Europe, limits for tolerable concentrations of "non-relevant metabolites" for active ingredients (AI) of plant protection products in drinking water between 0.1 and 10 microg/L are discussed depending on the toxicological information available. "Non-relevant metabolites" are degradation products of AIs, which do not or only partially retain the targeted toxicities of AIs. For "non-relevant metabolites" without genotoxicity (to be confirmed by testing in vitro), the application of the concept of "thresholds of toxicological concern" results in a health-based drinking water limit of 4.5 microg/L even for Cramer class III compounds, using the TTC threshold of 90 microg/person/day (divided by 10 and 2). Taking into account the thresholds derived from two reproduction toxicity data bases a drinking water limit of 3.0 microg/L is proposed. Therefore, for "non-relevant metabolites" whose drinking water concentration is below 3.0 microg/L, no toxicity testing is necessary. This work develops a toxicity assessment strategy as a basis to delineate health-based limits for "non-relevant metabolites" in ground and drinking water. Toxicological testing is recommended to investigate, whether the metabolites are relevant or not, based on the hazard properties of the parent AIs, as outlined in the SANCO Guidance document. Also, genotoxicity testing of the water metabolites is clearly recommended. In this publication, tiered testing strategies are proposed for non-relevant metabolites, when drinking water concentrations >3.0 microg/L will occur. Conclusions based on structure-activity relationships and the detailed toxicity database on the parent AI should be included. When testing in animals is required for risk assessment, key aspects are studies along OECD-testing guidelines with "enhanced" study designs addressing additional endpoints such as reproductive toxicity and a developmental screening test to derive health-based tolerable drinking water limits with a limited number

  9. Assessment of Cost Impacts of Using Non-Toxic Propulsion in Satellites

    Science.gov (United States)

    Schiebener, P. J.; Gies, O.; Stuhlberger, J.; Schmitz, H.-D.

    2002-01-01

    The growing costs of space missions, the need for increased mission performance, and concerns associated with environmental issues deeply influence propulsion system design and propellant selection criteria. A propellant's performance was defined in the past exclusively in terms of specific impulse and density, but now high-performance, non-toxic, non-sophisticated mono- propellant systems are key drivers, and are considered for development to replace the traditional hydrazine (N2H4) mono-propellant thrusters. The mono-propellants under consideration are propellant formulations, which should be environmentally friendly, should have a high density, equal or better performance and better thermal characteristics than hydrazine. These considerations raised interest specially in the candidates of Hydroxylammonium Nitrate (HAN)-based propellants, Ammoniumdinitramide (ADN)-based propellants, Tri-ethanol (TEAN)-based propellants, Hydrazinium Nitroformate (HNF)-based propellants, Hydrogen Peroxide (H2O2)-based propellants. A near-term objective in consideration of satellite related process optimisation is to significantly reduce on-ground operations costs and at the same time improve mission performance. A far-term objective is to obtain a system presenting a very high performance, illustrated by a high specific impulse. Moving to a "non-toxic" propulsion system seems to be a solution to these two goals. The sought after benefits for non-toxic spacecraft mono-propellant propulsion are under investigation taking into account the four main parameters which are mandatory for customer satisfaction while meeting the price constraints: - Reliability, availability, maintainability and safety, - Manufacturing, assembly, integration and test, - Launch preparation and support, - Ground support equipment. These benefits of non-toxic mono-propellants can be proven by various examples, like an expected reduction of development costs due the non-toxicity of propellants which might allow

  10. Methodological approach for the assessment of acute inhalation toxicity of smoke ammunitions by in silico, in vitro and in vivo modelling

    NARCIS (Netherlands)

    Pradines, E.; Glacial, F.; Medus, D.; Stiee, E.; Fedou, F.; Hulst, M. van; Klerk, W.P.C. de

    2015-01-01

    Assessing the toxicity of military pyrotechnic products is a growing challenge in the current context of Human and Environment protection. The Allied Ordnance Publication (AOP) 45 and the Standard NATO Agreement (STANAG) 4588 “Guidelines for toxicity testing of smokes, obscurants and pyrotechnics mi

  11. IN-SEASON ASSESSMENT OF WHEAT CROP HEALTH USING VEGETATION INDICES BASED ON GROUND MEASURED HYPER SPECTRAL DATA

    Directory of Open Access Journals (Sweden)

    Khalid Ali Al-Gaadi

    2014-01-01

    Full Text Available An experiment on a 50 ha center pivot field was conducted to determine the Vegetation Indices (VI’s that were helpful in assessing the in-season performance of wheat crop treated with graded levels of irrigation water and fertilizers. The irrigation levels were at 100, 90, 80 and 70% evapotranspiration (ETc; however, the fertilizer levels of N: P: K kg-1ha included 300:150:200 (low; 400:250:300 (medium and 500:300:300 (High. The crop was sown on January 1st and harvested on May 9th, 2012. Temporal data on biophysical parameters and reflectance of the crop in hyper spectral bands (350-2500 nm were collected at booting and ripening growth stages (February 17th and April 5th, 2012. Results of the study revealed that many of the tested spectral indices showed significant response to irrigation levels. Out of those, only two spectral indices (Plant Senescence Reflectance Index ‘PSRI’ and Photochemical Reflectance Index ‘PRI’ also exhibited significant response to fertilizer levels. The Middle Infrared-Based Vegetation Index (MIVI showed a significant response to the irrigation levels for both sampling dates. Among the tested spectral indices, Normalized Difference Infrared Index (NDII and Normalized Difference Nitrogen Index (NDNI exhibited the highest correlation to crop Leaf Area Index (LAI. Five indices showed the most response to wheat grain yield. These indices included Near Infrared band (NIR, Water Band Index (WBI, Normalized Water Index-1 (NWI-1, Normalized Water Index-3 (NWI-3 and Normalized Water Index-4 (NWI-4.

  12. Comparison of two screening bioassays, based on the frog sciatic nerve and yeast cells, for the assessment of herbicide toxicity.

    Science.gov (United States)

    Papaefthimiou, Chrisovalantis; Cabral, Maria de Guadalupe; Mixailidou, Christina; Viegas, Cristina A; Sá-Correia, Isabel; Theophilidis, George

    2004-05-01

    Two different test systems, one based on the isolated sciatic nerve of an amphibian and the other on a microbial eukaryote, were used for the assessment of herbicide toxicity. More specifically, we determined the deleterious effects of increasing concentrations of herbicides of different chemical classes (phenoxyacetic acids, triazines, and acetamides), and of 2,4-dichlorophenol (2,4-DCP), a degradation product of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), on electrophysiological parameters and the vitality of the axons of the isolated sciatic nerve of the frog (Rana ridibunda) and on the growth curve of the yeast Saccharomyces cerevisiae based on microtiter plate susceptibility assays. The no-observed-effect-concentration (NOEC), defined as the maximum concentration of the tested compound that has no effect on these biological parameters, was estimated. In spite of the different methodological approaches and biological systems compared, the NOEC values were identical and correlated with the lipophilicity of the tested compounds. The relative toxicity established here, 2,4-DCP > alachlor, metolachlor > metribuzin > 2,4-D, 2-methyl-4-chlorophenoxyacetic acid (MCPA), correlates with the toxicity indexes reported in the literature for freshwater organisms. Based on these results, we suggest that the relatively simple, rapid, and low-cost test systems examined here may be of interest as alternative or complementary tests for toxicological assessment of herbicides. PMID:15180372

  13. Atmospheric deposition of trace elements around point sources and human health risk assessment. II: Uptake of arsenic and chromium by vegetables grown near a wood preservation factory

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Moseholm, Lars; Nielsen, Margot M.

    1992-01-01

    Kale, lettuce, carrots and potatoes were grown in 20 experimental plots surrounding a wood preservation factory, to investigate the amount and pathways for plant uptake of arsenic and chromium. Arsenate used in the wood preservation process is converted to the more toxic arsenite by incineration...... of waste wood and is emitted into the atmosphere. Elevated concentrations of inorganic arsenic and chromium were found both in the test plants and in the soil around the factory. Multivariate statistical analysis of the results indicated that the dominating pathway of arsenic and chromium from the factory...... to the leafy vegetables grown nearby was by direct atmospheric deposition, while arsenic in the root crops originated from both the soil and the atmosphere. Consumption of vegetables grown near the source would result in an increased intake of inorganic arsenic, but the intake via the total diet was estimated...

  14. FUEL MANAGER: a vegetation assessment and manipulation software for wildfire modeling

    OpenAIRE

    Rigolot, Eric; de Coligny, Francois; Dreyfus, Philippe; Dupuy, Jean-Luc; Lecomte, Isabelle; Pezzatti, Boris; Vigy, Oana; Pimont, François

    2010-01-01

    The FUEL MANAGER is a CAPSIS module that is devoted to fuel modeling, fuel build-up and fire effect assessment. The CAPSIS platform (http://www.inra.fr/capsis) is a software package designed to host forestry models, either growth and yield or dynamics models. In the FUEL MANAGER, fuel modeling is based on a description of the physical properties of the thin particles (leaves, twigs) involved in fire propagation. Three-dimensional scenes can be built and visualized and different kinds of objec...

  15. Application of nuclear technique to assess the optimization and benefits from bio and organic fertilization of some vegetables

    International Nuclear Information System (INIS)

    Two field experiments were, conducted in the Plant Nutrition and Fertilization Unit, Soils and Water Department Nuclear Research Center, Atomic Energy Authority, Inshas, Egypt, assessing application of N in totally organic or totally mineral or different mixtures with the rat of N (being fixed) with or without bio fertilizers carried out following design factorial complete block design with three replicates .In the first one, pea was planted and in the second cucumber was planted in the same plots. This study was planned to Determine the contribution of mineral, organic and bio fertilizers in supplying plant with nitrogen using nuclear technology 15N and assess the optimization and benefits from bio and organic fertilization of some vegetables .Fertilization treatments indicated that the combination of 50% mineral fertilizer + 50% organic compost was superior over all other treatments. It means that half of the recommended dose of mineral fertilizer is enough to meet the requirement of pea and cucumber crops when supplemented with organic compost. This combination may have an environmental impact since it would reduce the risks of chemical fertilizers.

  16. Organ-on-a-chip: development and clinical prospects toward toxicity assessment with an emphasis on bone marrow.

    Science.gov (United States)

    Kim, Jeehye; Lee, Hanna; Selimović, Šeila; Gauvin, Robert; Bae, Hojae

    2015-05-01

    Conventional approaches for toxicity evaluation of drugs and chemicals, such as animal tests, can be impractical due to the large experimental scale and the immunological differences between species. Organ-on-a-chip models have recently been recognized as a prominent alternative to conventional toxicity tests aiming to simulate the human in vivo physiology. This review focuses on the organ-on-a-chip applications for high-throughput screening of candidate drugs against toxicity, with a particular emphasis on bone-marrow-on-a-chip. Studies in which organ-on-a-chip models have been developed and utilized to maximize the efficiency and predictability in toxicity assessment are introduced. The potential of these devices to replace tests of acute systemic toxicity in animals, and the challenges that are inherent in simulating the human immune system are also discussed. As a promising approach to overcome the limitations, we further focus on an in-depth analysis of the development of bone-marrow-on-a-chip that is capable of simulating human immune responses against external stimuli due to the key roles of marrow in immune systems with hematopoietic activities. Owing to the complex interactions between hematopoietic stem cells and marrow microenvironments, precise control of both biochemical and physical niches that are critical in maintenance of hematopoiesis remains a key challenge. Thus, recently developed bone-marrow-on-a-chip models support immunogenicity and immunotoxicity testing in long-term cultivation with repeated antigen stimulation. In this review, we provide an overview of clinical studies that have been carried out on bone marrow transplants in patients with immune-related diseases and future aspects of clinical and pharmaceutical application of bone-marrow-on-a-chip.

  17. Role of surface modification in zinc oxide nanoparticles and its toxicity assessment toward human dermal fibroblast cells

    Directory of Open Access Journals (Sweden)

    Ramasamy M

    2014-08-01

    Full Text Available Mohankandhasamy Ramasamy,1 Minakshi Das,1 Seong Soo A An,1 Dong Kee Yi2 1Division of Bionanotechnology, Gachon University, Seongnam, 2Department of Chemistry, Myongji University, Yongin, South Korea Abstract: The wide-scale applications of zinc oxide (ZnO nanoparticles (NPs in ­photocatalysts, gas sensors, and cosmetics may cause toxicity to humans and environments. Therefore, the aim of the present study was to reduce the toxicity of ZnO NPs by coating them with a silica (SiO2 layer, which could be used in human applications, such as cosmetic preparations. The sol–gel method was used to synthesize core ZnO with SiO2-shelled NPs (SiO2/ZnO NPs with varying degrees of coating. Diverse studies were performed to analyze the toxicity of NPs against cells in a dose- and time-dependent manner. To ensure the decreased toxicity of the produced SiO2/ZnO NPs, cytotoxicity in membrane damage and/or intracellular reactive oxygen species (ROS were assessed by employing 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide, lactate dehydrogenase, 2',7'-dichlorofluorescin, and lipid peroxide estimations. The cores of ZnO NPs exhibited cytotoxicity over time, regardless of shell thickness. Nevertheless, the thicker SiO2/ZnO NPs revealed reduced enzyme leakage, decreased peroxide production, and less oxidative stress than their bare ZnO NPs or thinner SiO2/ZnO NPs. Therefore, thicker SiO2/ZnO NPs moderated the toxicity of ZnO NPs by restricting free radical formation and the release of zinc ions, and decreasing surface contact with cells. Keywords: zinc oxide, silica coating, photostability, human dermal fibroblast, membrane damage, oxidative stress

  18. Arsenic concentration in rice, fish, meat and vegetables in Cambodia: a preliminary risk assessment.

    Science.gov (United States)

    Wang, Hong-Sheng; Sthiannopkao, Suthipong; Chen, Zhuo-Jia; Man, Yu-Bon; Du, Jun; Xing, Guang-Hua; Kim, Kyoung-Woong; Mohamed Yasin, Mohamed Salleh; Hashim, Jamal Hisham; Wong, Ming-Hung

    2013-12-01

    To assess arsenic contaminations and its possible adverse health effects, food samples were collected from Kandal, Kratie and Kampong Cham in Cambodia. The highest and the lowest concentrations were observed in fish (mean 2,832 ng g(-1), ww) collected from Kandal province and cattle stomach (1.86 ± 1.10 ng g(-1), ww) collected from Kratie, respectively. The daily intake of arsenic via food consumption was 604, 9.70 and 136 μg day(-1) in Kandal, Kratie and Kampong Cham, respectively. The arsenic dietary intake in Kandal ranked No. 1 among all the 17 compared countries or regions. Fish consumption contributed the greatest proportion of total arsenic daily intake in Kandal (about 63.0 %) and Kampong Cham (about 69.8 %). It is revealed to be a much more important exposure pathway than drinking water for residents in Kampong Cham. The results of risk assessment suggested that the residents in Cambodia, particularly for people in Kandal province, suffer high public health risks due to consuming arsenic-contaminated food.

  19. Assessment of microcystis bloom toxicity associated with wildlife mortality in the Kruger National Park, South Africa.

    Science.gov (United States)

    Masango, Mxolisi G; Myburgh, Jan G; Labuschagne, Leonie; Govender, Danny; Bengis, Roy G; Naicker, Dharmarai

    2010-01-01

    Based on previous necropsy results, Microcystis blooms in constructed water impoundments in the Kruger National Park (KNP) have been identified as a cause of wildlife mortality. In response to wildlife mortality during 2007, water samples, containing algal bloom material, were collected during February 2007 and July 2007 from four dams (Nhlanganzwani, Mpanamana, Makhohlola, and Sunset) in the southeastern part of the KNP as part of the follow-up investigation. The toxicity of the Microcystis blooms was determined using the enzyme-linked immunosorbent assay (ELISA), protein phosphatase inhibition (PPI) assay, mouse bioassay, and African sharptooth catfish (Clarias gariepinus) primary hepatocytes. Both the ELISA and PPI assays indicated that the water sample collected during February 2007 from the Nhlanganzwani Dam, and samples collected from the Nhlanganzwani and Sunset dams in June 2007, were toxic. These dams, exhibiting the toxic Microcystis blooms, were also associated with the wildlife mortality. Mice injected intraperitoneally with water samples from Nhlanganzwani Dam (February 2007) induced hepatotoxicity and mortality within 1 hr. Primary hepatocytes from the sharptooth catfish exposed to samples from these dams gave similar results. This laboratory investigation and results strongly incriminate the toxic Microcystis blooms as the cause of the wildlife mortality. Eutrophication and bloom formation appear to have been the consequence of the high numbers of hippopotami (Hippopotamus amphibius) in specific dams.

  20. 40 CFR 79.62 - Subchronic toxicity study with specific health effect assessments.

    Science.gov (United States)

    2010-07-01

    ...) Neurotoxicity (NTX) measures. NTX measures include (A) histopathology of specified central and peripheral... subjects to complete the histopathology requirements of both the GFAP and the general toxicity portion of... kidney function. The selection of specific tests will be influenced by observations on the mode of...

  1. Assessment of acute toxicity of carbofuran in Macrobrachium olfersii (Wiegmann, 1836) at different temperature levels.

    Science.gov (United States)

    Barbieri, Edison; Moreira, Priscila; Luchini, Luiz Alberto; Hidalgo, Karla Ruiz; Muñoz, Alejandro

    2016-01-01

    Carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate; C12H15NO3) is one of the most toxic carbamate pesticides. For acute toxicity of carbofuran, juveniles of Macrobrachium olfersii were exposed to different concentrations of carbofuran using the static renewal method at different temperature levels (15, 20 and 25°C) at pH 7.0. The main purpose of the present study was to detect the acute toxicity of carbofuran to M. olfersii and investigate its effects on oxygen consumption and ammonium excretion; these tests have not been carried out in this species before. First, the acute toxicity - median lethal concentration - of carbofuran to M. olfersii for 24, 48, 72 and 96 h was examined, which resulted in the following values: 1.64, 1.22, 0.86 and 0.42 mg L(-1), respectively. Furthermore, we also found that carbofuran caused an inhibition in oxygen consumption of 60.6, 65.3 and 66.2% with respect to the control. In addition, after separate exposures to carbofuran, elevations in ammonium excretion were more than 500% with respect to the control.

  2. An assessment of the environmental toxicity of hexavalent chromium in fish

    NARCIS (Netherlands)

    Putte, van der I.

    1981-01-01

    At present chromium is a common contaminant in surface waters in many countries. In water the metal may be present in the trivalent form (CrIII) or in the hexavalent form (CrVI), the latter of which is more toxic to aquatic organisms.The investigations presented in this thesis were aimed at a thorou

  3. A high-throughput method for assessing chemical toxicity using a Caenorhabditis elegans reproduction assay

    International Nuclear Information System (INIS)

    The National Research Council has outlined the need for non-mammalian toxicological models to test the potential health effects of a large number of chemicals while also reducing the use of traditional animal models. The nematode Caenorhabditis elegans is an attractive alternative model because of its well-characterized and evolutionarily conserved biology, low cost, and ability to be used in high-throughput screening. A high-throughput method is described for quantifying the reproductive capacity of C. elegans exposed to chemicals for 48 h from the last larval stage (L4) to adulthood using a COPAS Biosort. Initially, the effects of exposure conditions that could influence reproduction were defined. Concentrations of DMSO vehicle ≤ 1% did not affect reproduction. Previous studies indicated that C. elegans may be influenced by exposure to low pH conditions. At pHs greater than 4.5, C. elegans reproduction was not affected; however below this pH there was a significant decrease in the number of offspring. Cadmium chloride was chosen as a model toxicant to verify that automated measurements were comparable to those of traditional observational studies. EC50 values for cadmium for automated measurements (176-192 μM) were comparable to those previously reported for a 72-h exposure using manual counting (151 μM). The toxicity of seven test toxicants on C. elegans reproduction was highly correlative with rodent lethality suggesting that this assay may be useful in predicting the potential toxicity of chemicals in other organisms.

  4. Assessment of Toxic Metals and feed habits of the snail Pomacea specie from the Amatitlan Lake

    International Nuclear Information System (INIS)

    In the present thesis an assesment of cadmium, cooper, cromium VI, and lead was made in samples of snail pomacea specie from the Amatitlan Lake. We conclude that the comsuption of this mollusk is toxic for human health. The concentration of heavy metals like cadmium, cooper shows that are not recomended for human comsuption according to Spanish and FAO/PAHO standards

  5. Transformation of benzophenone-type UV filters by chlorine: Kinetics, products identification and toxicity assessments.

    Science.gov (United States)

    Li, Jian; Ma, Li-yun; Xu, Li

    2016-07-01

    The present study focused on the kinetics, transformation pathways and toxicity of several benzophenone-type ultraviolet filters (BPs) during the water chlorination disinfection process. The transformation kinetics of the studied three BPs was found to be second-order reaction, which was dependent on the concentration of BPs and chlorine. The second-order rate constants increased from 86.7 to 975 M(-1) s(-1) for oxybenzone, 49.6-261.7 M(-1) s(-1) for 4-hydroxybenzophenone and 51.7-540 M(-1) s(-1) for 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid with the increasing pH value from 6 to 8 of the chlorination disinfection condition. Then the transformation products (TPs) of these BPs were identified by HPLC-QTof analysis. Several transformation pathways, including electrophilic substitution, methoxyl substitution, ketone groups oxidation, hydrolysis, decarboxylation and ring cleavage reaction, were speculated to participate in the chlorination transformation process. Finally, according to the toxicity experiment on luminescent bacteria, Photobacterium phosphoreum, enhanced toxicity was observed for almost all the TPs of the studied BPs except for 2,2'-dihydroxy-4,4'-dimethoxybenzophenone; it suggested the formation of TPs with more toxic than the parent compounds during the chlorination process. The present study provided a foundation to understand the transformation of BPs during chlorination disinfection process, and was of great significance to the drinking water safety.

  6. Assessment of the toxicity of waste water from a textile industry to Cyprinus carpio.

    Science.gov (United States)

    Roopadevi, H; Somashekar, R K

    2012-03-01

    Static, short-term, acute toxicity tests were performed over a period of 96 hrs using different concentrations of influent and effluent of textile industry waste water with the objective of evaluating their acute toxicity on fresh water fish, Cyprinus carpio (common carp). The LC50 24, 48, 72 and 96 hr of influent and effluent were 25.9, 21.10, 15.66, 11.11% (v/v) and 63.18, 54.89, 48.62, 36.04% (v/v), respectively. The acute toxic unit TUa values for 24, 48, 72, 96 hr for influent and effluent are 3.85, 4.73, 6.38, 8.99 and 1.58, 1.82, 2.05, 2.77, respectively. Correspondingly, the TF was found to be 1, 1.22, 1.65 and 2.33 for influent, and for effluent 1, 1.15, 1.29 and 1.75. Total efficiency of the treatment was 69.16% and the safe concentration of effluent is set to be 3.60%. These data are highly useful in establishing limits of acceptability by the aquatic animals. The need to introduce toxicity evaluation assay for confirming the quality of effluent from the point view of effective environmental safe limits and to ensure integrity of aquatic environment, is stressed. PMID:23033675

  7. Characterization of Airborne Particles in an Electronic Waste Recycling Facility and Their Toxicity Assessment

    Science.gov (United States)

    Improper disposal of electronic waste (e-waste) can lead to release of toxic chemicals into the environment and also may pose health risks. Thus, recycling e-waste, instead of landfilling, is considered to be an effective way to reduce pollutant release and exposure. However, lit...

  8. Multi-Year Assessment of Toxic Genotypes and Microcystin Concentration in Northern Lake Taihu, China

    Science.gov (United States)

    Hu, Lili; Shan, Kun; Lin, Lizhou; Shen, Wei; Huang, Licheng; Gan, Nanqin; Song, Lirong

    2016-01-01

    Lake Taihu is the third-largest freshwater lake in China and has been suffering from cyanobacterial blooms for over two decades. The northern part of the lake, Meiliang Bay, is known to be at high risk of dense and sustained Microcystis blooms and toxins. This study aimed to investigate and record the annual and seasonal dynamics of toxic genotype, Microcystis morphospecies succession and microcystin variation. It also aimed to find out the underlying driving factors influencing the dynamic changes. Microcystin (MC) and the Microcystis genotype were quantified using HPLC and quantitative real-time PCR, respectively. Our study, over three consecutive years, showed that the pattern of morphospecies succession was seasonally distinct and annually consistent. During the same period in 2012, 2013 and 2014, the average MC were, on dry weight basis, 733 μg·g−1, 844 μg·g−1, 870 μg·g−1, respectively. The proportion of toxic Microcystis accounted for 41%, 44% and 52%, respectively. Cell bound microcystin was found to correlate with the percentage of toxic Microcystis. Based on historical and current data, we conclude that annual bloom toxicity was relatively stable or possibly increased over the last decade. PMID:26784229

  9. Exploratory breath analyses for assessing toxic dermal exposure of firefighters during suppression of structural burns

    Science.gov (United States)

    Firefighters wear fireproof clothing and self-contained breathing apparatus (SCBA) during rescue and fire suppression activities to protect against acute effects from heat and toxic chemicals. Fire services are also concerned about long-term health outcomes from chemical exposure...

  10. Pollution by metals and toxicity assessment using Caenorhabditis elegans in sediments from the Magdalena River, Colombia.

    Science.gov (United States)

    Tejeda-Benitez, Lesly; Flegal, Russell; Odigie, Kingsley; Olivero-Verbel, Jesus

    2016-05-01

    The Magdalena River is the most important river in Colombia, supplying over 70% of the population of fish and drinking water, and it also is the main river transportation way of the country. It receives effluents from multiple sources along its course such as contaminant agricultural and industrial discharges. To evaluate the toxicity profile of Magdalena River sediments through endpoints such as survival, locomotion, and growth, wild type strains of Caenorhabditis elegans were exposed to aqueous extracts of the sediments. To identify changes in gene expression, GFP transgenic strains were used as reporter genes. Physiological and biochemical data were correlated with metal concentration in the sediments, identifying patterns of toxicity along the course of the river. Levels of some metals such as Cd, Cu, and Ni were above TEC and PEC limits. Effects in survival, growth, and locomotion were observed in most of the samples, and changes in gene expression were evident in the genes mtl-2, sod-4, and gst-1 using fluorescence expression. Cadmium and lead were the metals which were primarily associated with sediment toxicity, and the sampling sites with the highest increased expression of stress response genes were Barrancabermeja and Girardot. However, the diverse nature of toxic profiles observed in C. elegans in the study area showed the pervasiveness of different types of discharges throughout the river system. PMID:26851980

  11. Water quality assessment in piracicamirim creek upstream and downstream a sugar and ethanol industry through toxicity tests with cladocerans

    Directory of Open Access Journals (Sweden)

    Rafael Grossi Botelho

    2012-08-01

    Full Text Available An environmental impact study was conducted to determine the Piracicamirim's creek water quality in order to assess the influence of effluents from a sugar industry in this water body. For this, toxicity tests were performed with a water sample upstream and downstream the industry using the microcrustaceans Daphnia magna, Ceriodaphnia dubia and Ceriodaphnia silvestrii as test organisms, as well as physical and chemical analysis of water. Results showed that physical and chemical parameters did not change during the sampling period, except for the dissolved oxygen. No toxicity was observed for D. magna and reproduction of C. dubia and C. silvestrii in both sampling points. Thus, the industry was not negatively impacting the quality of this water body.

  12. Assessing metal toxicity in sediments using the equilibrium partitioning model and empirical sediment quality guidelines: A case study in the nearshore zone of the Bohai Sea, China

    International Nuclear Information System (INIS)

    Highlights: • Based on the EqP model, 35% samples had potential metal toxicity in sediments. • The empirical SQGs are not suitable for assessing sediment toxicity in Bohai Sea. • The EqP model is a much needed tool for metal toxicity assessment in coastal China. - Abstract: Surface sediments were collected from five nearshore (wastewater discharges, aquaculture facilities and a seaport) sites in Bohai Bay and Laizhou Bay, China. The equilibrium partitioning (EqP) model and empirical sediment quality guidelines (SQGs) were applied to assess the potential metal toxicity in the collected sediments. The results show that, based on the EqP model, 35% of stations exhibited potential metal toxicity. Several metals (Cu, Ni and Cr) exceeded the empirical SQGs (9–93% of the time), however these guidelines may not be suitable for use in the Bohai Sea owing to the background concentrations. The EqP model is a more useful method for assessing potential metal toxicity in Bohai Sea sediment than the empirical SQGs. Additionally, we have provided new understanding about methods for assessing sediment metal toxicity in the Bohai Sea that may be useful in other coastal areas in China

  13. Assessment of toxicity of polycyclic aromatic hydrocarbons in sediments of Kaohsiung Harbor, Taiwan.

    Science.gov (United States)

    Chen, Chih-Feng; Chen, Chiu-Wen; Dong, Cheng-Di; Kao, Chih-Ming

    2013-10-01

    Polycyclic aromatic hydrocarbon (PAH) contamination and toxicity levels in the surface sediments of Kaohsiung Harbor, Taiwan were evaluated using sediment quality guidelines (SQGs) and toxic equivalent factors. Eighty surface sediment samples were collected from twenty locations in Kaohsiung Harbor for PAH analysis using gas chromatography/mass spectrometry (GC/MS). Concentrations of total PAHs varies from 34.0 to 16,700 ng/g with a mean concentration of 1490±2689 ng/g. The spatial distribution of PAHs reveals that PAH concentration is relatively higher in the river mouth regions, especially in the Salt River mouth where it gradually diminishes toward the harbor region. Distributions of PAHs, during both the wet and dry seasons, show that PAHs are more easily disbursed in the receiving sea water thereby leading to a wider range of chemical distribution. Hence, most of the chemicals accumulate in the harbor water channel. Diagnostic ratios show that the possible source of PAHs in the southern industrial area of the harbor could be coal combustion while in the other zones it could be petroleum combustion and/or a mixed sources. The toxic equivalent concentrations (TEQ(carc)) of PAHs varied from 3.9 to 1970 ng TEQ/g. The higher total TEQ(carc) values were found in the southern industrial area of the harbor. As compared with US sediment quality guidelines, the observed levels of PAHs in the industrial zone exceeded the effects range low (ERL), which will eventually cause acute biological damage. Based on the analyses using the SQGs, surface sediments from Kaohsiung Harbor were moderately contaminated and most samples have a low probability of toxicity pollution, except for the Salt River mouth situated in the south Kaohsiung Harbor area. This area has a medium to high probability of toxicity pollution. PMID:22818911

  14. Spatial and seasonal toxicity in a stormwater management facility: evidence obtained by adapting an integrated sediment quality assessment approach.

    Science.gov (United States)

    Tixier, Guillaume; Rochfort, Quintin; Grapentine, Lee; Marsalek, Jiri; Lafont, Michel

    2012-12-15

    Stormwater ponds have been widely used to control increased surface runoff resulting from urbanization, and to enhance runoff quality. As receiving waters, they are impacted by intermittent stormwater pollution while also serving as newly created aquatic habitats, which partly offset changes of aquatic ecosystems and their biodiversity by urbanization. Thus, determining ecological risks in stormwater ponds is important for the preservation and rehabilitation of biodiversity in urban areas. Limitations of the conventional toxicity assessment techniques in stormwater ponds have led us to use the sediment quality triad approach with the specific analyses of oligochaetes. The latter analyses build on the earlier work by the Cemagref (Lyon, France) and use the oligochaetes as bioindicators of the sediment quality. This integrative approach was tested at eight sites in the Terraview-Willowfield stormwater facility in Toronto, Ontario, in all four seasons (summer 2008-spring 2009). The facility receives direct runoff from the MacDonald-Cartier freeway with a traffic intensity of 340,000 vehicles/d. Sediment chemistry results indicate that several heavy metals and PAH compounds exceeded the Ontario sediment quality guidelines in the facility. Regardless of the season, laboratory bioassays revealed a strong spatial variation in sediment toxicity along the flow path from the inlet to the outlet, agreeing with decreasing concentrations of contaminants in sediment, especially of heavy metals. However, in situ assessments of the benthic macroinvertebrate community structure and in particular of the oligochaete community revealed an overriding influence of seasonally varying toxicity. This seasonal pattern was described as high toxicity in spring and recovery in fall and corresponded to the influx and flushing-out of road salts and of several heavy metals within the facility. PMID:22212882

  15. Bioaccumulation of Antimony and Arsenic in Vegetables and Health Risk Assessment in the Superlarge Antimony-Mining Area, China

    OpenAIRE

    Defang Zeng; Saijun Zhou; Bozhi Ren; Tengshu Chen

    2015-01-01

    Heavy metal pollution in soils caused by mining and smelting has attracted worldwide attention for its potential health risks to residents. This paper studies the concentrations and accumulations of Sb and As in both soils and vegetables and the human health risks of Sb and As in vegetables from Xikuangshan (XKS) Sb mine, Hunan, China. Results showed that the soils were severely polluted by Sb and As; Sb and As have significant positive correlation. Sb and As concentrations in vegetables were...

  16. Evaluating the use of digital repeat photography to assess seasonal sensitivity of vegetation to climate in the tropics

    Science.gov (United States)

    Ramos-Chavez, J.; Lougheed, V.; Tweedie, C. E.; Rayadin, Y.; Syaifudin, Y.

    2013-12-01

    Plant phenology is the study of life cycle responses of vegetation to seasonal variations in environmental factors. Phenological timing is sensitive to small fluctuations of climate and is easy to observe, thus it is considered to be one of the best biological indicators of variability and change. The relatively low cost and ease of use of ground-based repeat digital photography (DRP) makes this an ideal tool for deployment in remote locations, Indonesia for example. Indonesia is a tropical biodiversity hotspot and an important component of the global carbon cycle. In recent decades, ecosystems found here have been modified as a result anthropogenic activities, such as forestry and mining, as well as changes in climate patterns. Understanding phenological changes among different forest types is important in assessing which forest type appears to be most sensitive to change. To compare phenology among different forest types in Indonesia and to determine whether DRP can pick up seasonal vegetative signals, several landcover types (i.e., plantations, mangrove, primary and secondary forests) were monitored using DRP. Images were analyzed using a Matlab script that compares the brightness of Red, Green and Blue channels to interpret the Green Excess Index (GEI) in response to seasonal climatic fluctuations (i.e. temperature and precipitation). Seasonal trends in green up were compared among the different land cover types and correlated with climate data. Results indicate that the use of DRP can in fact illustrate phenological dynamics in response to seasonal climatic variability. Most sites showed a decrease in GEI during the rainy season, with increasing green up months thereafter. Responses to such changes in environmental factors were most noticeable (sensitive) in heavily impacted landcover types, secondary forests for example, which showed higher variability and sensitivity to environmental changes. Within one secondary forest a significant, positive relationship

  17. Assessment of toxicity based criteria for disposal of drilling waste in oil and gas exploration

    International Nuclear Information System (INIS)

    Options for the disposal of drilling wastes are defined by the Alberta Energy and Utilities Board under the jurisdiction of the Drilling Waste Management guideline. Because of concerns that bacterial luminescence test may not provide an adequate degree of environmental protection, a representative sample (60 in all) of drilling wastes have been tested using a battery of tests. These tests include bacterial luminescence, growth respiration, genotoxicity, plant seed emergence, root elongation, duckweed and algal growth, survival of aquatic invertebrate species, worm avoidance, trout embryo development and fathead minnow survival. Thirty of the sixty drilling muds were toxic to bioluminescence. A complete chemical analysis was done on all drilling muds and results were ranked and consolidated into a toxicity index. To ensure the highest level of environmental protection, the multitrophic level approach is recommended, assuming that costs are in line with the expected benefits

  18. Comprehensive assessment of toxic emissions from coal-fired power plants

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T D; Schmidt, C E [USDOE Pittsburgh Energy Technology Center, PA (United States); Radziwon, A S [Burns and Roe Services Corp., Pittsburgh, PA (United States)

    1991-01-01

    The Pittsburgh Energy Technology Center (PETC) of the US Department of Energy (DOE) has two current investigations, initiated before passage of the Clean Air Act Amendment (CAAA), that will determine the air toxic emissions from coal-fired electric utilities. DOE has contracted with Battelle Memorial Institute and Radian corporation to conduct studies focusing on the potential air toxics, both organic and inorganic, associated with different size fractions of fine particulate matter emitted from power plant stacks. Table 2 indicates the selected analytes to be investigated during these studies. PETC is also developing guidance on the monitoring of Hazardous Air Pollutants (HAPS) to be incorporated in the Environmental Monitoring plans for the demonstration projects in its Clean Coal Technology Program.

  19. Antibacterial activity of neem nanoemulsion and its toxicity assessment on human lymphocytes in vitro

    OpenAIRE

    Jerobin, Jayakumar; Makwana, Pooja; Suresh Kumar, RS; Sundaramoorthy, Rajiv; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2015-01-01

    Neem (Azadirachta indica) is recognized as a medicinal plant well known for its antibacterial, antimalarial, antiviral, and antifungal properties. Neem nanoemulsion (NE) (O/W) is formulated using neem oil, Tween 20, and water by high-energy ultrasonication. The formulated neem NE showed antibacterial activity against the bacterial pathogen Vibrio vulnificus by disrupting the integrity of the bacterial cell membrane. Despite the use of neem NE in various biomedical applications, the toxicity s...

  20. Toxicity assessment of combined fluoroquinolone and tetracycline exposure in zebrafish (Danio rerio).

    OpenAIRE

    Zhang, Y; Wang, X.; Yin, X.; Shi, M.; Dahlgren, RA; Wang, H

    2016-01-01

    Fluoroquinolones (FQs) and tetracyclines (TCs), the two β-diketone antibiotics (DKAs), are two frequently detected pollutants in the environment; however, little data are available on their combined toxicity to zebrafish (Danio rerio). This study reports that toxicologic effects of combined DKA (FQs-TCs) exposure on zebrafish were comparable with or slightly less than those of TCs alone, showing that TCs played a major toxicologic role in the mixtures. The effects of FQs, TCs, and DKAs on mal...