Contaminant mixtures and repoductive health: Developmental toxicity effects in rats after mixed exposure to environmentally relevant endocrine disrupting chemicals, with focus on effects in females

DEFF Research Database (Denmark)

Jacobsen, Pernille Rosenskjold; Christiansen, Sofie; Hass, Ulla

proposed that a similar syndrome, called the ovarian dysgenesis syndrome (ODS), exists for females. This syndrome encompasses alterations in reproductive development caused by chemical exposure in sensitive windows of development that may result in fecundity impairments, gravid diseases, gynecological...... disorders or later onset adult diseases. However, experimental evidence on the effects of developmental exposure to environmentally relevant endocrine disrupting chemicals in females has been missing attention. Since chemical exposure can affect female reproductive development it is important to investigate......, mixtures were modeled based on high end human intakes, and the project involved two developmental mixture studies in rats, called Contamed 1 and 2. In these studies 13 chemicals where data on in vivo endocrine disrupting effects and information on human exposures was available, were selected. The tested...

Process for the separation of contaminant or mixture of contaminants from a Ch4-comprising gaseous feed streem

NARCIS (Netherlands)

2012-01-01

The invention provides a process for the separation of a contaminant or mixture of contaminants from a CH4-comprising gaseous feed streem, comprising the subsequent steps of: a) passing a CH4-comprising gaseous feed streem comprising the contaminant or the mixture of contaminants in to and through a

Biological indicators capable of assessing thermal treatment efficiency of hydrocarbon mixture-contaminated soil.

Science.gov (United States)

Wang, Jiangang; Zhan, Xinhua; Zhou, Lixiang; Lin, Yusuo

2010-08-01

In China, there are many special sites for recycling and washing the used drums, which release a variety of C5-C40 hydrocarbon mixture into the soil around the site. The remediation of these contaminated sites by thermal treatment is adopted ubiquitously and needs to be assessed. Here we report the feasibility of biological indicators applied to assess thermal treatment efficiency in such contaminated soil. A series of biological indicators, including seed germination index (SGI), root elongation index (REI), plant growth height, biomass, carbon dioxide evolved (CDE), soil respiration inhibition (SRI) and soil enzymatic activities, were employed to monitor or assess hydrocarbon mixture removal in thermal treated soil. The results showed that residual hydrocarbon mixture content correlated strongly negatively with SGI for sesamum (Sesamum indicum L.), plant height, and biomass for ryegrass (Lolium perenne L.) in the concentration ranges of 0-3990, 0-3170 and 0-2910 mg kg(-1), respectively. In contrast, REI for sesamum was positively correlated with residual hydrocarbon mixture content from 0 to 1860 mg kg(-1). In addition, both CDE and SRI demonstrated that 600 mg kg(-1) of residual hydrocarbon mixture content caused the highest amount of soil carbon dioxide emission and inhabitation of soil respiration. The results of soil enzymes indicated that 1000 mg kg(-1) of residual hydrocarbon mixture content was the threshold value of stimulating or inhibiting the activities of phosphatase and catalase, or completely destroying the activities of dehydrogenase, invertase, and urease. In conclusion, these biological indicators can be used as a meaningful complementation for traditional chemical content measurement in evaluating the environmental risk of the contaminated sites before and after thermal treatment. (c) 2010 Elsevier Ltd. All rights reserved.

Toxicological responses of environmental mixtures: Environmental metal mixtures display synergistic induction of metal-responsive and oxidative stress genes in placental cells

Energy Technology Data Exchange (ETDEWEB)

Adebambo, Oluwadamilare A. [Department of Biological Sciences, North Carolina State University (United States); Ray, Paul D. [Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill (United States); Shea, Damian [Department of Biological Sciences, North Carolina State University (United States); Fry, Rebecca C., E-mail: rfry@unc.edu [Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill (United States)

2015-12-15

Exposure to elevated levels of the toxic metals inorganic arsenic (iAs) and cadmium (Cd) represents a major global health problem. These metals often occur as mixtures in the environment, creating the potential for interactive or synergistic biological effects different from those observed in single exposure conditions. In the present study, environmental mixtures collected from two waste sites in China and comparable mixtures prepared in the laboratory were tested for toxicogenomic response in placental JEG-3 cells. These cells serve as a model for evaluating cellular responses to exposures during pregnancy. One of the mixtures was predominated by iAs and one by Cd. Six gene biomarkers were measured in order to evaluate the effects from the metal mixtures using dose and time-course experiments including: heme oxygenase 1 (HO-1) and metallothionein isoforms (MT1A, MT1F and MT1G) previously shown to be preferentially induced by exposure to either iAs or Cd, and metal transporter genes aquaporin-9 (AQP9) and ATPase, Cu{sup 2+} transporting, beta polypeptide (ATP7B). There was a significant increase in the mRNA expression levels of ATP7B, HO-1, MT1A, MT1F, and MT1G in mixture-treated cells compared to the iAs or Cd only-treated cells. Notably, the genomic responses were observed at concentrations significantly lower than levels found at the environmental collection sites. These data demonstrate that metal mixtures increase the expression of gene biomarkers in placental JEG-3 cells in a synergistic manner. Taken together, the data suggest that toxic metals that co-occur may induce detrimental health effects that are currently underestimated when analyzed as single metals. - Highlights: • Toxicogenomic responses of environmental metal mixtures assessed • Induction of ATP7B, HO-1, MT1A, MT1F and MT1G by metal mixtures observed in placental cells • Higher gene induction in response to metal mixtures versus single metal treatments.

Toxicological responses of environmental mixtures: Environmental metal mixtures display synergistic induction of metal-responsive and oxidative stress genes in placental cells

International Nuclear Information System (INIS)

Adebambo, Oluwadamilare A.; Ray, Paul D.; Shea, Damian; Fry, Rebecca C.

2015-01-01

Exposure to elevated levels of the toxic metals inorganic arsenic (iAs) and cadmium (Cd) represents a major global health problem. These metals often occur as mixtures in the environment, creating the potential for interactive or synergistic biological effects different from those observed in single exposure conditions. In the present study, environmental mixtures collected from two waste sites in China and comparable mixtures prepared in the laboratory were tested for toxicogenomic response in placental JEG-3 cells. These cells serve as a model for evaluating cellular responses to exposures during pregnancy. One of the mixtures was predominated by iAs and one by Cd. Six gene biomarkers were measured in order to evaluate the effects from the metal mixtures using dose and time-course experiments including: heme oxygenase 1 (HO-1) and metallothionein isoforms (MT1A, MT1F and MT1G) previously shown to be preferentially induced by exposure to either iAs or Cd, and metal transporter genes aquaporin-9 (AQP9) and ATPase, Cu 2+ transporting, beta polypeptide (ATP7B). There was a significant increase in the mRNA expression levels of ATP7B, HO-1, MT1A, MT1F, and MT1G in mixture-treated cells compared to the iAs or Cd only-treated cells. Notably, the genomic responses were observed at concentrations significantly lower than levels found at the environmental collection sites. These data demonstrate that metal mixtures increase the expression of gene biomarkers in placental JEG-3 cells in a synergistic manner. Taken together, the data suggest that toxic metals that co-occur may induce detrimental health effects that are currently underestimated when analyzed as single metals. - Highlights: • Toxicogenomic responses of environmental metal mixtures assessed • Induction of ATP7B, HO-1, MT1A, MT1F and MT1G by metal mixtures observed in placental cells • Higher gene induction in response to metal mixtures versus single metal treatments

Nutrients versus emerging contaminants-Or a dynamic match between subsidy and stress effects on stream biofilms.

Science.gov (United States)

Aristi, I; Casellas, M; Elosegi, A; Insa, S; Petrovic, M; Sabater, S; Acuña, V

2016-05-01

Freshwater ecosystems are threatened by multiple anthropogenic stressors, which might be differentiated into two types: those that reduce biological activity at all concentrations (toxic contaminants), and those that subsidize biological activity at low concentrations and reduce it at high concentrations (assimilable contaminants). When occurring in mixtures, these contaminants can have either antagonistic, neutral or synergistic effects; but little is known on their joint effects. We assessed the interaction effects of a mixture of assimilable and toxic contaminants on stream biofilms in a manipulative experiment using artificial streams, and following a factorial design with three nutrient levels (low, medium or high) and either presence or absence of a mixture of emerging contaminants (ciprofloxacin, erythromycin, diclofenac, methylparaben, and sulfamethoxazole). We measured biofilm biomass, basal fluorescence, gross primary production and community respiration. Our initial hypotheses were that biofilm biomass and activity would: increase with medium nutrient concentrations (subsidy effect), but decrease with high nutrient concentrations (stress effect) (i); decrease with emerging contaminants, with the minimum decrease at medium nutrient concentrations (antagonistic interaction between nutrients subsidy and stress by emerging contaminants) and the maximum decrease at high nutrient concentrations (synergistic interaction between nutrients and emerging contaminants stress) (ii). All the measured variables responded linearly to the available nutrients, with no toxic effect at high nutrient concentrations. Emerging contaminants only caused weak toxic effects in some of the measured variables, and only after 3-4 weeks of exposure. Therefore, only antagonistic interactions were observed between nutrients and emerging contaminants, as medium and high nutrient concentrations partly compensated the harmful effects of emerging contaminants during the first weeks of the

Contamination Effects Due to Space Environmental Interactions

Science.gov (United States)

Chen, Philip T.; Paquin, Krista C. (Technical Monitor)

2001-01-01

Molecular and particulate contaminants are commonly generated from the orbital spacecraft operations that are under the influence of the space environment. Once generated, these contaminants may attach to the surfaces of the spacecraft or may remain in the vicinity of the spacecraft. In the event these contaminants come to rest on the surfaces of the spacecraft or situated in the line-of-sight of the observation path, they will create various degrees of contamination effect which may cause undesirable effects for normal spacecraft operations, There will be circumstances in which the spacecraft may be subjected to special space environment due to operational conditions. Interactions between contaminants and special space environment may alter or greatly increase the contamination effect due to the synergistic effect. This paper will address the various types of contamination generation on orbit, the general effects of the contamination on spacecraft systems, and the typical impacts on the spacecraft operations due to the contamination effect. In addition, this paper will explain the contamination effect induced by the space environment and will discuss the intensified contamination effect resulting from the synergistic effect with the special space environment.

Combined Contamination and Space Environmental Effects on Solar Cells and Thermal Control Surfaces

Science.gov (United States)

Dever, Joyce A.; Bruckner, Eric J.; Scheiman, David A.; Stidham, Curtis R.

1994-01-01

For spacecraft in low Earth orbit (LEO), contamination can occur from thruster fuel, sputter contamination products and from products of silicone degradation. This paper describes laboratory testing in which solar cell materials and thermal control surfaces were exposed to simulated spacecraft environmental effects including contamination, atomic oxygen, ultraviolet radiation and thermal cycling. The objective of these experiments was to determine how the interaction of the natural LEO environmental effects with contaminated spacecraft surfaces impacts the performance of these materials. Optical properties of samples were measured and solar cell performance data was obtained. In general, exposure to contamination by thruster fuel resulted in degradation of solar absorptance for fused silica and various thermal control surfaces and degradation of solar cell performance. Fused silica samples which were subsequently exposed to an atomic oxygen/vacuum ultraviolet radiation environment showed reversal of this degradation. These results imply that solar cells and thermal control surfaces which are susceptible to thruster fuel contamination and which also receive atomic oxygen exposure may not undergo significant performance degradation. Materials which were exposed to only vacuum ultraviolet radiation subsequent to contamination showed slight additional degradation in solar absorptance.

Investigate the influence of halloysite and activated carbon mixtures in phytostabilization of Pb-contaminated soil with Lolium perenne L.

Directory of Open Access Journals (Sweden)

Radziemska Maja

2017-06-01

Full Text Available A pot experiment was conducted to investigate the effects of halloysite and activated carbon mixtures on the biomass and distribution of macronutrients (Mg, K, Ca, Na, P in ryegrass grown in Pb-contaminated soil. The soil was spiked with four different levels of lead contamination, i.e. 0 (control, 200, 400, 800 mg·kg−1 were applied in an analytical grade Pb(NO32 solution mixed thoroughly with the soil. Raw halloysite (3% and activated carbon (1% relative to soil mass mixtures were used to reduce the effect of soil lead contamination. Ryegrass of the Bokser variety was harvested after 42 days, and soil samples were collected for laboratory tests. The mixture of sorbents applied in the experiment which turned out to be most effective at doses of lead amounting to 400 and 800 mg·kg−1 of soil, with the increase in the yield of ryegrass being the highest. Increasing contamination of soil with lead in the series without the mixture of sorbents increased the contents of phosphorus, sodium, calcium and magnesium in ryegrass. The applied mixture of halloysite and activated carbon changed the macronutrient concentration in ryegrass, with the greatest changes found in that of potassium and sodium.

Effects of environmental contaminants on reptiles: A review

Science.gov (United States)

Hall, R.J.

1980-01-01

The literature relating to the effects of environmental contaminants on reptiles is reviewed and certain generalizations based on studies of other kinds of vertebrates are presented. Reports of reptilian mortality from pesticide applications are numerous enough to establish the sensitivity of reptiles to these materials. Reports of residue analyses demonstrate the ability of reptiles to accumulate various contaminants. but the significance of the residues to reptilian populations is unknown. A few authors have reported the distribution of residues in reptilian tissues; others have investigated uptake or loss rates. Physiological studies have shown that organochlorines may inhibit enzymes involved in active transport and have correlated the activity of potential detoxifying enzymes with residue levels. There is some suggestion that pesticide residues may interfere with reproduction in oviparous snakes. Needs for future research are discussed.

Effects of an environmentally-relevant mixture of pyrethroid insecticides on spontaneous activity in primary cortical networks on microelectrode arrays.

Science.gov (United States)

Johnstone, Andrew F M; Strickland, Jenna D; Crofton, Kevin M; Gennings, Chris; Shafer, Timothy J

2017-05-01

Pyrethroid insecticides exert their insecticidal and toxicological effects primarily by disrupting voltage-gated sodium channel (VGSC) function, resulting in altered neuronal excitability. Numerous studies of individual pyrethroids have characterized effects on mammalian VGSC function and neuronal excitability, yet studies examining effects of complex pyrethroid mixtures in mammalian neurons, especially in environmentally relevant mixture ratios, are limited. In the present study, concentration-response functions were characterized for five pyrethroids (permethrin, deltamethrin, cypermethrin, β-cyfluthrin and esfenvalerate) in an in vitro preparation containing cortical neurons and glia. As a metric of neuronal network activity, spontaneous mean network firing rates (MFR) were measured using microelectorde arrays (MEAs). In addition, the effect of a complex and exposure relevant mixture of the five pyrethroids (containing 52% permethrin, 28.8% cypermethrin, 12.9% β-cyfluthrin, 3.4% deltamethrin and 2.7% esfenvalerate) was also measured. Data were modeled to determine whether effects of the pyrethroid mixture were predicted by dose-addition. At concentrations up to 10μM, all compounds except permethrin reduced MFR. Deltamethrin and β-cyfluthrin were the most potent and reduced MFR by as much as 60 and 50%, respectively, while cypermethrin and esfenvalerate were of approximately equal potency and reduced MFR by only ∼20% at the highest concentration. Permethrin caused small (∼24% maximum), concentration-dependent increases in MFR. Effects of the environmentally relevant mixture did not depart from the prediction of dose-addition. These data demonstrate that an environmentally relevant mixture caused dose-additive effects on spontaneous neuronal network activity in vitro, and is consistent with other in vitro and in vivo assessments of pyrethroid mixtures. Published by Elsevier B.V.

Environmental restoration and biological contamination: ecological and legal aspects

Directory of Open Access Journals (Sweden)

Ademir Reis

2005-05-01

Full Text Available Environmental restoration is a pressing current need. However, protected areas have been exposed to biological contamination risks because the traditional techniques of restoration frequently use exotic species. This causes some concern, since biological contamination is the second major cause of species extinction in the world. It is important to use only native species in restoration projects in order to promote an effective environmental restoration without the risk of contamination. This paper discusses some issues concerning environmental restoration, biological contamination and the need for clearer laws.

Toxicological Responses of Environmental Mixtures: Environmental Metals Mixtures Display Synergistic Induction of Metal-Responsive and Oxidative Stress Genes in Placental Cells

Science.gov (United States)

Adebambo, Oluwadamilare A.; Ray, Paul D.; Shea, Damian; Fry, Rebecca C.

2016-01-01

Exposure to elevated levels of the toxic metals inorganic arsenic (iAs) and cadmium (Cd) represents a major global health problem. These metals often occur as mixtures in the environment, creating the potential for interactive or synergistic biological effects different from those observed in single exposure conditions. In the present study, environmental mixtures collected from two waste sites in China and comparable mixtures prepared in the laboratory were tested for toxicogenomic response in placental JEG-3 cells. These cells serve as a model for evaluating cellular responses to exposures during pregnancy. One of the mixtures was predominated by iAs and one by Cd. Six gene biomarkers were measured in order to evaluate the effects from the metals mixtures using dose and time-course experiments including: heme oxygenase 1 (HO-1) and metallothionein isoforms (MT1A, MT1F and MT1G) previously shown to be preferentially induced by exposure to either iAs or Cd, and metal transporter genes aquaporin-9 (AQP9) and ATPase, Cu2+ transporting, beta polypeptide (ATP7B). There was a significant increase in the mRNA expression levels of ATP7B, HO-1, MT1A, MT1F, and MT1G in mixture-treated cells compared to the iAs or Cd only-treated cells. Notably, the genomic responses were observed at concentrations significantly lower than levels found at the environmental collection sites. These data demonstrate that metal mixtures increase the expression of gene biomarkers in placental JEG-3 cells in a synergistic manner. Taken together, the data suggest that toxic metals that co-occur may induce detrimental health effects that are currently underestimated when analyzed as single metals. PMID:26472158

Toxicity of inorganic contaminants, individually and in environmental mixtures, to three endangered fishes (Colorado squawfish, bonytail, and razorback sucker)

Science.gov (United States)

Buhl, Kevin J.; Hamilton, S.J.

1996-01-01

Two life stages of three federally-listed endangered fishes, Colorado squawfish (Ptychocheilus lucius), bonytail (Gila elegans), and razorback sucker (Xyrauchen texanus) were exposed to copper, selenate, selenite, and zinc individually, and to mixtures of nine inorganics in a reconstituted water that simulated the water quality of the middle Green River, Utah. The mixtures simulated environmental ratios of arsenate, boron, copper, molybdenum, selenate, selenite, uranium, vanadium, and zinc in two tributaries, Ashley Creek and Stewart Lake outlet, of the middle Green River. The rank order of toxicity of the individual inorganics, from most to least toxic, was: copper > zinc > selenite > selenate. Colorado squawfish larvae were more sensitive to all four inorganics and the two mixtures than the juveniles, whereas there was no consistent response between the two life stages for the other two species. There was no consistent difference in sensitivity to the inorganics among the three endangered fishes. Both mixtures exhibited either additive or greater than additive toxicity to these fishes. The primary toxic components in the mixtures, based on toxic units, were copper and zinc. Acute toxicity values were compared to measured environmental concentrations in the two tributaries to derive margins of uncertainty. Margins of uncertainty were low for both mixtures (9–22 for the Stewart Lake outlet mixture, and 12–32 for the Ashley Creek mixture), indicating that mixtures of inorganics derived from irrigation activities may pose a hazard to endangered fishes in the Green River.

The Effects of Environmental Factors on Biological Remediation of Petroleum Hydrocarbon Contaminated Soil

Directory of Open Access Journals (Sweden)

Mohammad reza Moslemi

2005-09-01

Full Text Available Among the consequences of discharging industrial wastes to land and water bodies, is the widespread accumulation and migration of toxic chemical mixtures in soil and groundwater resources. It is believed that the accumulation of contaminants in the environment constitutes a serious threat to ecological and human health. Bioremediation is an effective measure in dealing with such contaminations particularly those from petroleum hydrocarbon sources; moreover bioremediation is emerging as a promising technology for the treatment of soil and groundwater contamination. Therefore the goal of this study is discussing the theory and practice of biological remediation of petroleum hydrocarbon contaminated soils and assessing the effects of operational conditions and parameters such as: temperature, dissolved oxygen concentration and  pH on the removal rate of the target contaminant which is handled in the designed reactor. Due to large production and consumption rate of diesel fuel inIran and many other countries, diesel fuel has been selected as target contaminant. In this study TOC and COD testing methods have been used to measure and assess the removal rate of the contaminant in the reactor. The experimental results indicate that, considering the operational conditions the indigenous microorganisms which have been separated from the soil are able to remove 50 to 83 percent of the contaminant after 30 days. Thereafter on the base of the results and considering the laboratorial specifications and conditions applied in this project, the optimum values of temperature, dissolved oxygen concentration andpH were respectively determined as 35°C, 4mg/L and 7.

Northern contaminant mixtures induced morphological and functional changes in human coronary artery endothelial cells under culture conditions typifying high fat/sugar diet and ethanol exposure.

Science.gov (United States)

Florian, Maria; Yan, Jin; Ulhaq, Saad; Coughlan, Melanie; Laziyan, Mahemuti; Willmore, William; Jin, Xiaolei

2013-11-16

It has been reported that Northern populations are exposed to mixtures of various environmental contaminants unique to the Arctic (Northern contaminant mixtures - NCM) at a large range of concentrations, depending on their geological location, age, lifestyle and dietary habits. To determine if these contaminants may contribute to a cardiovascular health risk, especially when combined with a high fat and sugar diet and ethanol exposure, we treated human coronary artery endothelial cells (HCAEC) with two mixtures of 4 organic (NCM1) or 22 organic and inorganic (NCM2) chemicals detected in Northerners' blood during 2004-2005 in the presence or absence of low-density lipoprotein (1.5mg/ml), very-low-density lipoprotein (1.0mg/ml) and glucose (10mmol/L) (LVG), and in the absence or presence of 0.1% ethanol. After 24h of exposure, cell morphology and markers of cytotoxicity and endothelial function were examined. NCM1 treatment did not affect cell viability, but increased cell size, disrupted cell membrane integrity, and decreased cell density, uptake of small peptides, release of endothelin-1 (ET-1) and plasminogen activator inhibitor (PAI), while causing no changes in endothelial nitric oxide synthase (eNOS) protein expression and nitric oxide (NO) release. In contrast, NCM2 decreased cell viability, total protein yield, uptake of small peptides, eNOS protein expression, and NO release and caused membrane damage, but caused no changes in the secretion of ET-1, prostacyclin and PAI. The presence of LVG and/or alcohol did or did not influence the effects of NCM1 or NCM2 depending on the endpoint and the mixture examined. These results suggested that the effects of one or one group of contaminants may be altered by the presence of other contaminants, and that with or without the interaction of high fat and sugar diet and/or ethanol exposure, NCMs at the concentrations used caused endothelial dysfunction in vitro. It remains to be investigated if these effects of NCMs also

Environmental contamination and breathing disease

International Nuclear Information System (INIS)

Cardona A, Jose D

2003-01-01

The atmospheric contamination is the main component of the environmental contamination and it can be defined as the presence in the atmosphere of an or several substances in enough quantity to produce alterations of the health, it is presented in aerosol form, with its gassy and specific components, altering the quality of the population's life and the degradation of the ecosystems. The main pollutant, as much for the frequency as for the importance of its effects, is the smoke of cigarettes. The paper mentions other types of polluting agents and their effects in the breathing apparatus

Environmental contaminants, ecosystems and human health

Energy Technology Data Exchange (ETDEWEB)

Majumdar, S.K.; Miller, E.W.; Brenner, F.J. [eds.] [Lafayette College, Easton, PA (United States). Dept. of Biology

1995-12-31

The authors cover a variety of concerns regarding the adverse impacts of contaminants on ecosystems and human health. The twelve chapters in the first section of the text address the impact of contaminants on ecosystem function, and ten of the remaining twenty-two chapters are devoted to the effects of contaminants on human health. Part three presents eight case studies in humans, while the final four chapters provide the reader with an assessment of environmental problems and analyses. Two chapters, on the health effects of power plant generated air pollution and on black lung disease, have been abstracted separately for the IEA Coal Research CD-ROM.

Comparative Analysis of Stress Induced Gene Expression in Caenorhabditis elegans following Exposure to Environmental and Lab Reconstituted Complex Metal Mixture.

Directory of Open Access Journals (Sweden)

Ranjeet Kumar

Full Text Available Metals are essential for many physiological processes and are ubiquitously present in the environment. However, high metal concentrations can be harmful to organisms and lead to physiological stress and diseases. The accumulation of transition metals in the environment due to either natural processes or anthropogenic activities such as mining results in the contamination of water and soil environments. The present study used Caenorhabditis elegans to evaluate gene expression as an indicator of physiological response, following exposure to water collected from three different locations downstream of a Swedish mining site and a lab reconstituted metal mixture. Our results indicated that the reconstituted metal mixture exerted a direct stress response in C. elegans whereas the environmental waters elicited either a diminished or abrogated response. This suggests that it is not sufficient to use the biological effects observed from laboratory mixtures to extrapolate the effects observed in complex aquatic environments and apply this to risk assessment and intervention.

Effects of inter-varietal diversity, biotic stresses and environmental productivity on grain yield of spring barley variety mixtures

DEFF Research Database (Denmark)

Kiær, Lars Pødenphant; Skovgaard, Ib M.; Østergård, Hanne

2012-01-01

than their component varieties when accounting also for the general response to environmental productivity. Hence, most mixtures adapted slightly better to environmental productivity and were less sensitive to environmental stress than their component varieties. We conclude that the efficacy of variety...... mixtures may be enhanced by mixing relatively high-yielding varieties differing in responsiveness to environmental productivity.......Varietal seed mixtures tend to increase and stabilize crop yields, yet their application is sparse. Large-scale cultivation of variety mixtures may require a better understanding of how inter-varietal interactions and their interaction with the environment may influence the grain yield of variety...

Effects of environmental contaminants on snapping turtles of a tidal wetland

Energy Technology Data Exchange (ETDEWEB)

Albers, P H; Sileo, L; Mulhern, B M

1986-01-01

Snapping turtles (Chelydra serpentina) were collected from a brackish-water and a nearly freshwater area in the contaminated Hackensack Meadowlands of New Jersey and an uncontaminated freshwater area in Maryland to determine the effects of environmental contaminants on a resident wetland species. No turtles were observed or caught in Meadowlands at two trapping sites that were the most heavily contaminated by metals. Snapping turtles from the brackish-water area had an unusually low lipid content of body fat and reduced growth compared to turtles from the freshwater areas in New Jersey and Maryland. Despite the serious metal contamination of the Hackensack Meadowlands, the metal content of kidneys and livers from New Jersey turtles was low and not greatly different from that of the Maryland turtles. Organochlorine pesticide concentrations in body fat were generally low at all three study areas. Polychlorinated biphenyls (PCBs) concentrations in fat were highest in male turtles from the New Jersey brackish-water area. Analysis of blood for amino-levulinic acid dehydratase, albumin, glucose, hemoglobin, osmolatility, packed cell volume, total protein, triglycerides, and uric acid failed to reveal any differences among groups that would indicated physiological impairment related to contaminants.

Effects of environmental contaminants on snapping turtles of a tidal wetland

Science.gov (United States)

Albers, P.H.; Sileo, L.; Mulhern, B.M.

1986-01-01

Snapping turtles (Chelydra serpentina) were collected from a brackish-water and a nearly freshwater area in the contaminated Hackensack Meadowlands of New Jersey and an uncontaminated freshwater area in Maryland to determine the effects of environmental contaminants on a resident wetland species. No turtles were observed or caught in the Meadowlands at two trapping sites that were the most heavily contaminated by metals. Snapping turtles from the brackish-water area had an unusually low lipid content of body fat and reduced growth compared to turtles from the fresh-water areas in New Jersey and Maryland. Despite the serious metal contamination of the Hackensack Meadowlands, the metal content of kidneys and livers from New Jersey turtles was low and not greatly different from that of the Maryland turtles. Organochlorine pesticide concentrations in body fat were generally low at all three study areas. Polychlorinated biphenyls (PCBs) concentrations in fat were highest in male turtles from the New Jersey brackish-water area. Analysis of blood for amino-levulinic acid dehydratase, albumin, glucose, hemoglobin, osmolality, packed cell volume, total protein, triglycerides, and uric acid failed to reveal any differences among groups that would indicate physiological impairment related to contaminants.

Selection of wild macrophytes for use in constructed wetlands for phytoremediation of contaminant mixtures.

Science.gov (United States)

Guittonny-Philippe, Anna; Petit, Marie-Eléonore; Masotti, Véronique; Monnier, Yogan; Malleret, Laure; Coulomb, Bruno; Combroux, Isabelle; Baumberger, Teddy; Viglione, Julien; Laffont-Schwob, Isabelle

2015-01-01

Constructed wetlands (CWs) offer an alternative to traditional industrial wastewater treatment systems that has been proved to be efficient, cost-effective and environmentally friendly. Most of the time, CWs are planted with proliferative species such as Phragmites australis or with plants originating from nurseries, both representing a risk for the natural biodiversity conservation of aquatic ecosystems located downstream of the CWs. For the removal of metals and organic pollutant mixtures present in industrial effluents, it is necessary to select tolerant plant species that are able to produce a high aboveground biomass and to develop a healthy belowground system. Wild plant species growing in aquatic bodies at industrial outfalls could constitute suitable tolerant species to use in CWs for industrial effluent treatment. To test this hypothesis, we assessed, under laboratory conditions (using an experimental design), the tolerance to mixtures of metals (Al, As, Cd, Cu, Cr, Fe, Mn, Ni, Pb, Sn, Zn) or/and organic pollutants (THC, PHE, PYR, LAS) of five European sub-cosmopolitan native macrophytes (Alisma lanceolatum, Carex cuprina, Epilobium hirsutum, Iris pseudacorus and Juncus inflexus) that had been collected in a polluted Mediterranean wetland, after a field study (crossing ecological relevés and analyses of contaminant concentrations in water and sediments). Our results demonstrated that research on phytoremediation of industrial effluents should focus much more on the use of native macrophytes growing at short distances from industrial discharges (such as C. cuprina in this study), and that root/shoot ratio, aerial height and proportion of green leaves are good and cost-effective indicators of plant tolerance to metals and organic pollutant mixtures in laboratory studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

Predicting the environmental fate properties of petroleum hydrocarbon mixtures

International Nuclear Information System (INIS)

Pisigan, R.A. Jr.; Tucker, W.A.

1995-01-01

The environmental fate and transport of petroleum products for risk assessment can be evaluated based on the physico-chemical properties of an indicator chemical or a surrogate compound, or the whole mixture. A study was conducted to develop a simple representation of the hydrocarbon mixture as if it contained only few constituents, each of which represents a large number of compounds. The products considered are gasoline, diesel fuel, and jet fuel (JP4). Each petroleum hydrocarbon was characterized as a mixture of six constituents: short chain alkanes, long chain alkanes, short chain cycloalkanes and alkenes, long chain cycloalkanes and alkenes, BTEX, and other aromatics. The carbon number used as a cut-off between short and long chain alkanes, alkenes, and cycloalkanes varies with the type of product. Each mixture has different average molecular weight, water solubility, vapor pressure, organic carbon partition coefficient, and air diffusivity. The properties of each constituent of gasoline were derived from the weighted average of all compounds belonging to each constituent group. For diesel fuel and JP4, the properties of each constituent were generated from the properties of the component most representative of the group. Any property that is missing or not available from common literature sources was derived from regression equations developed from the data base for gasoline. These regression equations express the property as function of the number of carbon atoms. The R 2 values of the regression equations range from 0.82--0.92. Some case studies involving petroleum product contamination in which the estimated properties were applied are presented

Complex contaminant mixtures in multistressor Appalachian riverscapes.

Science.gov (United States)

Merriam, Eric R; Petty, J Todd; Strager, Michael P; Maxwell, Aaron E; Ziemkiewicz, Paul F

2015-11-01

Runoff from watersheds altered by mountaintop mining in the Appalachian region (USA) is known to pollute headwater streams, yet regional-scale assessments of water quality have focused on salinization and selenium. The authors conducted a comprehensive survey of inorganic contaminants found in 170 stream segments distributed across a spectrum of historic and contemporary human land use. Principal component analysis identified 3 important dimensions of variation in water chemistry that were significantly correlated with contemporary surface mining (principal component 1: elevated dominant ions, sulfate, alkalinity, and selenium), coal geology and legacy mines (principal component 2: elevated trace metals), and residential development (principal component 3: elevated sodium and chloride). The combination of these 3 dominant sources of pollutants produced a complex stream-to-stream patchwork of contaminant mixtures. Seventy-five percent of headwater streams (catchments  5 km(2) ) were classified as having reference chemistries, and chemistries indicative of combined mining and development contaminants accounted for 47% of larger streams (compared with 26% of headwater streams). Extreme degradation of larger streams can be attributed to accumulation of contaminants from multiple human land use activities that include contemporary mountaintop mining, underground mining, abandoned mines, and untreated domestic wastewater. Consequently, water quality improvements in this region will require a multicontaminant remediation approach. © 2015 SETAC.

Chemical Mixtures Health Risk Assessment of Environmental Contaminants: Concepts, Methods, Applications

Science.gov (United States)

This problems-based, introductory workshop focuses on methods to assess health risks posed by exposures to chemical mixtures in the environment. Chemical mixtures health risk assessment methods continue to be developed and evolve to address concerns over health risks from multic...

Emerging contaminants in Belgian marine waters: single toxicant and mixture risks of pharmaceuticals.

Science.gov (United States)

Claessens, Michiel; Vanhaecke, Lynn; Wille, Klaas; Janssen, Colin R

2013-06-15

Knowledge on the effects of pharmaceuticals on aquatic marine ecosystems is limited. The aim of this study was therefore to establish the effect thresholds of pharmaceutical compounds occurring in the Belgian marine environment for the marine diatom Phaeodactylum tricornutum, and subsequently perform an environmental risk assessment for these substances. Additionally, a screening-level risk assessment was performed for the pharmaceutical mixtures. No immediate risk for acute toxic effects of these compounds on P. tricornutum were apparent at the concentrations observed in the Belgian marine environment. In two Belgian coastal harbours however, a potential chronic risk was observed for the β-blocker propranolol. No additional risks arising from the exposure to mixtures of pharmaceuticals present in the sampling area could be detected. However, as risk characterization ratios for mixtures of up to 0.5 were observed, mixture effects could emerge should more compounds be taken into account. Copyright © 2013 Elsevier Ltd. All rights reserved.

Dechlorination of Hexachlorobenzene in Contaminated Soils Using a Nanometallic Al/CaO Dispersion Mixture: Optimization through Response Surface Methodology

Science.gov (United States)

Jiang, Yuhui; Shang, Yixuan; Yu, Shuyao; Liu, Jianguo

2018-01-01

Hexachlorobenzene (HCB) contamination of soils remains a significant environmental challenge all over the world. Reductive stabilization is a developing technology that can decompose the HCB with a dechlorination process. A nanometallic Al/CaO (n-Al/CaO) dispersion mixture was developed utilizing ball-milling technology in this study. The dechlorination efficiency of HCB in contaminated soils by the n-Al/CaO grinding treatment was evaluated. Response surface methodology (RSM) was employed to investigate the effects of three variables (soil moisture content, n-Al/CaO dosage and grinding time) and the interactions between these variables under the Box-Behnken Design (BBD). A high regression coefficient value (R2 = 0.9807) and low p value (soil moisture content, n-Al/CaO dosage, and grinding time were found to be 7% (m/m), 17.7% (m/m), and 24 h, respectively, in the experimental ranges and levels. Under optimal conditions, the dechlorination efficiency was 80%. The intermediate product analysis indicated that dechlorination was the process by stepwise loss of chloride atoms. The main pathway observed within 24 h was HCB → pentachlorobenzene (PeCB) → 1,2,3,4-tetrachlorobenzene (TeCB) and 1,2,4,5-TeCB. The results indicated that the moderate soil moisture content was crucial for the hydrodechlorination of HCB. A probable mechanism was proposed wherein water acted like a hydrogen donor and promoted the hydrodechlorination process. The potential application of n-Al/CaO is an environmentally-friendly and cost-effective option for decontamination of HCB-contaminated soils. PMID:29702570

Assessment of immunotoxic effects of environmental contamination using a cotton rat model

International Nuclear Information System (INIS)

Zhang, Z.R.; Propst, T.L.; McMurry, S.T.; Lochmiller, R.L.; McBee, K.; Quails, C.W. Jr.; Burks, S.L.

1993-01-01

Adult National Institute of Health inbred cotton rats (Sigmodon hispidus) were housed in six terrestrial mesocosms on or near an abandoned oil refinery in central Oklahoma for 56 days. Exposure sites included three mesocosms located on sites judged to be contaminated with a variety of complex mixtures of contaminants and three matched reference mesocosm. In addition, wild cotton rats were collected from contaminated and reference areas near the mesocosm sites. Peripheral leukocyte and erythrocyte variables, secondary lymphoid organ weight and cellularity, proliferative response of splenocytes to mitogens, lymphocyte subpopulations, delayed-type hypersensitivity response, 24 h hypersensitivity, antibody response to keyhole limpet hemocyanin, NK cell activity, macrophage metabolic functions, and complement activity were measures as a comprehensive screen of immunocompetence. According to current data analysis, peripheral leukocyte numbers, mitogenic response of splenocytes, antibody response to keyhole limpet hemocyanin, delayed-type sensitivity and 24 h hypersensitivity were altered by contaminant exposure

Evaluating Complex Mixtures in the Zebrafish Embryo by Reconstituting Field Water Samples: A Metal Pollution Case Study

Directory of Open Access Journals (Sweden)

Ellen D. G. Michiels

2017-03-01

Full Text Available Accurately assessing the toxicity of complex, environmentally relevant mixtures remains an important challenge in ecotoxicology. The goal was to identify biological effects after exposure to environmental water samples and to determine whether the observed effects could be explained by the waterborne metal mixture found in the samples. Zebrafish embryos were exposed to water samples of five different sites originating from two Flemish (Mol and Olen, Belgium metal contaminated streams: “Scheppelijke Nete” (SN and “Kneutersloop” (K, and a ditch (D, which is the contamination source of SN. Trace metal concentrations, and Na, K, Mg and Ca concentrations were measured using ICP-MS and were used to reconstitute site-specific water samples. We assessed whether the effects that were observed after exposure to environmental samples could be explained by metal mixture toxicity under standardized laboratory conditions. Exposure to “D” or “reconstituted D” water caused 100% mortality. SN and reconstituted SN water caused similar effects on hatching, swim bladder inflation, growth and swimming activity. A canonical discriminant analysis confirmed a high similarity between both exposure scenarios, indicating that the observed toxicity was indeed primarily caused by metals. The applied workflow could be a valuable approach to evaluate mixture toxicity that limits time and costs while maintaining biological relevance.

Marine environmental contamination: public awareness, concern and perceived effectiveness in five European countries.

Science.gov (United States)

Jacobs, Silke; Sioen, Isabelle; De Henauw, Stefaan; Rosseel, Yves; Calis, Tanja; Tediosi, Alice; Nadal, Martí; Marques, António; Verbeke, Wim

2015-11-01

Given the potential of Perceived Consumer Effectiveness (PCE) in shaping pro-environmental behavior, the relationships between PCE, awareness of causes of contaminants in the marine environment, and concern about marine environmental contamination were investigated using Structural Equation Modeling (SEM). PCE is the belief that an individual has in being able to make a difference when acting alone. A web-based survey was performed in one western European country (Belgium), one northern European country (Ireland) and three southern European countries (Italy, Portugal and Spain), resulting in a total sample size of 2824 participants. The analyses confirm that European citizens are concerned about marine environmental problems. Participants from the southern countries reported the highest concern. In addition, the study participants did not have a strong belief in themselves in being capable of making a difference in tackling marine environmental problems. However, a higher awareness, which was associated with a higher degree of concern, enhanced the belief that an individual can make a difference in tackling marine environmental problems, though only when a concrete action was proposed. Consequently, information campaigns focusing on pro-environmental behavior are recommended to raise public awareness about marine environmental problems and at the same time explicitly refer to concrete possible actions. The findings indicate that when only awareness and concern are raised without mentioning a concrete action, PCE might even decrease and render the communication effort ineffective. Copyright © 2015 Elsevier Inc. All rights reserved.

How to develop scientific literacy on environmental contamination?

International Nuclear Information System (INIS)

Shimada, Yoko

2012-01-01

The knowledge and data on the environmental contamination should be smoothly communicated for environmental risk literacy. In this paper, the issues for environmental risk literacy are raised by referring the case of the environmental contamination with radionuclides released from the Fukushima Daiichi nuclear power plant accident. It is discussed that literacy for experts should be the capacity to explain the environmental contamination system with the global and long-term viewpoint and that the network between experts like SRA Japan should be necessary. (author)

Environmental contamination with Toxocara eggs

NARCIS (Netherlands)

Nijsse, Rolf; Mughini-Gras, Lapo; Wagenaar, J.A.; Franssen, Frits; Ploeger, Harm W.

2015-01-01

Background: Environmental contamination with Toxocara eggs is considered the main source of human toxocariasis. The contribution of different groups of hosts to this contamination is largely unknown. Current deworming advices focus mainly on dogs. However, controversy exists about blind deworming

Environmental Research Translation: Enhancing Interactions with Communities at Contaminated Sites

Science.gov (United States)

Ramirez-Andreotta, Monica D.; Brusseau, Mark L.; Artiola, Janick F.; Maier, Raina M.; Gandolfi, A. Jay

2014-01-01

The characterization and remediation of contaminated sites are complex endeavors fraught with numerous challenges. One particular challenge that is receiving increased attention is the development and encouragement of full participation by communities and community members affected by a given site in all facets of decision-making. Many disciplines have been grappling with the challenges associated with environmental and risk communication, public participation in environmental data generation, and decision-making and increasing community capacity. The concepts and methods developed by these disciplines are reviewed, with a focus on their relevance to the specific dynamics associated with environmental contamination sites. The contributions of these disciplines are then synthesized and integrated to help develop Environmental Research Translation (ERT), a proposed framework for environmental scientists to promote interaction and communication among involved parties at contaminated sites. This holistic approach is rooted in public participation approaches to science, which includes: a transdisciplinary team, effective collaboration, information transfer, public participation in environmental projects, and a cultural model of risk communication. Although there are challenges associated with the implementation of ERT, it is anticipated that application of this proposed translational science method could promote more robust community participation at contaminated sites. PMID:25173762

Developmental toxicity of PAH mixtures in fish early life stages. Part II: adverse effects in Japanese medaka.

Science.gov (United States)

Le Bihanic, Florane; Clérandeau, Christelle; Le Menach, Karyn; Morin, Bénédicte; Budzinski, Hélène; Cousin, Xavier; Cachot, Jérôme

2014-12-01

In aquatic environments, polycyclic aromatic hydrocarbons (PAHs) mostly occur as complex mixtures, for which risk assessment remains problematic. To better understand the effects of PAH mixture toxicity on fish early life stages, this study compared the developmental toxicity of three PAH complex mixtures. These mixtures were extracted from a PAH-contaminated sediment (Seine estuary, France) and two oils (Arabian Light and Erika). For each fraction, artificial sediment was spiked at three different environmental concentrations roughly equivalent to 0.5, 4, and 10 μg total PAH g(-1) dw. Japanese medaka embryos were incubated on these PAH-spiked sediments throughout their development, right up until hatching. Several endpoints were recorded at different developmental stages, including acute endpoints, morphological abnormalities, larvae locomotion, and genotoxicity (comet and micronucleus assays). The three PAH fractions delayed hatching, induced developmental abnormalities, disrupted larvae swimming activity, and damaged DNA at environmental concentrations. Differences in toxicity levels, likely related to differences in PAH proportions, were highlighted between fractions. The Arabian Light and Erika petrogenic fractions, containing a high proportion of alkylated PAHs and low molecular weight PAHs, were more toxic to Japanese medaka early life stages than the pyrolytic fraction. This was not supported by the toxic equivalency approach, which appeared unsuitable for assessing the toxicity of the three PAH fractions to fish early life stages. This study highlights the potential risks posed by environmental mixtures of alkylated and low molecular weight PAHs to early stages of fish development.

Dechlorination of Hexachlorobenzene in Contaminated Soils Using a Nanometallic Al/CaO Dispersion Mixture: Optimization through Response Surface Methodology

Directory of Open Access Journals (Sweden)

Yuhui Jiang

2018-04-01

Full Text Available Hexachlorobenzene (HCB contamination of soils remains a significant environmental challenge all over the world. Reductive stabilization is a developing technology that can decompose the HCB with a dechlorination process. A nanometallic Al/CaO (n-Al/CaO dispersion mixture was developed utilizing ball-milling technology in this study. The dechlorination efficiency of HCB in contaminated soils by the n-Al/CaO grinding treatment was evaluated. Response surface methodology (RSM was employed to investigate the effects of three variables (soil moisture content, n-Al/CaO dosage and grinding time and the interactions between these variables under the Box-Behnken Design (BBD. A high regression coefficient value (R2 = 0.9807 and low p value (<0.0001 of the quadratic model indicated that the model was accurate in predicting the experimental results. The optimal soil moisture content, n-Al/CaO dosage, and grinding time were found to be 7% (m/m, 17.7% (m/m, and 24 h, respectively, in the experimental ranges and levels. Under optimal conditions, the dechlorination efficiency was 80%. The intermediate product analysis indicated that dechlorination was the process by stepwise loss of chloride atoms. The main pathway observed within 24 h was HCB → pentachlorobenzene (PeCB → 1,2,3,4-tetrachlorobenzene (TeCB and 1,2,4,5-TeCB. The results indicated that the moderate soil moisture content was crucial for the hydrodechlorination of HCB. A probable mechanism was proposed wherein water acted like a hydrogen donor and promoted the hydrodechlorination process. The potential application of n-Al/CaO is an environmentally-friendly and cost-effective option for decontamination of HCB-contaminated soils.

Using model-based screening to help discover unknown environmental contaminants.

Science.gov (United States)

McLachlan, Michael S; Kierkegaard, Amelie; Radke, Michael; Sobek, Anna; Malmvärn, Anna; Alsberg, Tomas; Arnot, Jon A; Brown, Trevor N; Wania, Frank; Breivik, Knut; Xu, Shihe

2014-07-01

Of the tens of thousands of chemicals in use, only a small fraction have been analyzed in environmental samples. To effectively identify environmental contaminants, methods to prioritize chemicals for analytical method development are required. We used a high-throughput model of chemical emissions, fate, and bioaccumulation to identify chemicals likely to have high concentrations in specific environmental media, and we prioritized these for target analysis. This model-based screening was applied to 215 organosilicon chemicals culled from industrial chemical production statistics. The model-based screening prioritized several recognized organosilicon contaminants and generated hypotheses leading to the selection of three chemicals that have not previously been identified as potential environmental contaminants for target analysis. Trace analytical methods were developed, and the chemicals were analyzed in air, sewage sludge, and sediment. All three substances were found to be environmental contaminants. Phenyl-tris(trimethylsiloxy)silane was present in all samples analyzed, with concentrations of ∼50 pg m(-3) in Stockholm air and ∼0.5 ng g(-1) dw in sediment from the Stockholm archipelago. Tris(trifluoropropyl)trimethyl-cyclotrisiloxane and tetrakis(trifluoropropyl)tetramethyl-cyclotetrasiloxane were found in sediments from Lake Mjøsa at ∼1 ng g(-1) dw. The discovery of three novel environmental contaminants shows that models can be useful for prioritizing chemicals for exploratory assessment.

Chemical Mixtures Health Risk Assessment of Environmental Contaminants: Concepts, Methods, And Applications

Science.gov (United States)

This problems-based, introductory workshop focuses on methods to assess health risks posed by exposures to chemical mixtures in the environment. Chemical mixtures health risk assessment methods continue to be developed and evolve to address concerns over health risks from multic...

Environmental Research Translation: Enhancing Interactions with Communities at Contaminated Sites

Science.gov (United States)

Ramirez-Andreotta, M.; Brusseau, M. L. L.; Artiola, J. F.; Maier, R. M.; Gandolfi, A. J.

2015-12-01

The characterization and remediation of contaminated sites are complex endeavors fraught with numerous challenges. One particular challenge that is receiving increased attention is the development and encouragement of full participation by communities and community members affected by a given site in all facets of decision-making. Many disciplines have been grappling with the challenges associated with environmental and risk communication, public participation in environmental data generation and decision-making, and increasing community capacity. The concepts and methods developed by these disciplines are reviewed, with a focus on their relevance to the specific dynamics associated with contaminated sites. The contributions of these disciplines are then synthesized and integrated to help develop Environmental Research Translation (ERT), a proposed framework for environmental scientists to promote interaction and communication among involved parties at contaminated sites. This holistic approach is rooted in public participation approaches to science, which includes: a transdisciplinary team, effective collaboration, information transfer, public participation in environmental projects, and a cultural model of risk communication. Although there are challenges associated with the implementation of ERT, it is anticipated that application of this proposed translational science method could promote more robust community participation at contaminated sites.

A preliminary investigation of the environmental impact of a thermal power plant in relation to PCB contamination.

Science.gov (United States)

Gedik, Kadir; Imamoglu, Ipek

2011-07-01

The most significant application of polychlorinated biphenyls (PCBs) is in transformers and capacitors. Therefore, power plants are important suspected sources for entry of PCBs into the environment. In this context, the levels and distribution of PCBs in sediment, soil, ash, and sludge samples were investigated around Seyitömer thermal power plant, Kütahya, Turkey. Moreover, identity and contribution of PCB mixtures were predicted using the chemical mass balance (CMB) receptor model. United States Environmental Protection Agency methods were applied during sample preparation, extraction (3540C), cleanup (3660B, 3665A, 3630C), and analysis (8082A). ΣPCB concentrations in the region ranged from not detected to 385 ng/g dry weight, with relatively higher contamination in sediments in comparison to soil, sludge, and ash samples collected from around the power plant. Congener profiles of the sediment and soil samples show penta-, hexa-, and hepta-chlorobiphenyls as the major homolog groups. The results from the CMB model indicate that PCB contamination is largely due to Clophen A60/A40 and Aroclor 1254/1254(late)/1260 release into the sediment and sludge samples around the thermal power plant. Since there are no other sources of PCBs in the region and the identity of PCB sources estimated by the CMB model mirrors PCB mixtures contained in transformers formerly used in the plant, the environmental contamination observed especially in sediments is attributed to the power plant. Release of PCBs over time, as indicated by the significant concentrations observed even in surface samples, emphasizes the importance of the need for better environmental management.

Analytical methods for the determination of mixtures of bisphenols and derivatives in human and environmental exposure sources and biological fluids. A review

International Nuclear Information System (INIS)

Caballero-Casero, N.; Lunar, L.; Rubio, S.

2016-01-01

Bisphenol A (BPA) is ubiquitous in humans and the environment. Its potential adverse effects through genomic and non-genomic pathways have fostered BPA replacement by bisphenol analogs that, unfortunately, exert similar adverse effects. Many of these analogs, as well as their derivatives, have already found in humans and the environment and major concerns have arisen over their low dose- and mixture-related effects. This review aims to discuss the characteristics of the main analytical methods reported so far for the determination of mixtures of bisphenol analogs and/or derivatives in human and environmental exposure sources and biological fluids. Approaches followed for removal of background contamination, sample preparation and separation and detection of mixtures of bisphenols and derivatives are critically discussed. Sample treatment is matrix-dependent and common steps include analyte isolation, removal of interferences, evaporation of the extracts and solvent reconstitution. Separation and quantification has been almost exclusively carried out by liquid chromatography tandem mass spectrometry (LC-MS/MS) or gas chromatography mass spectrometry (GC–MS), in the last case prior derivatization, but LC-fluorescence detection has also found some applications. Main characteristics, advantages and drawbacks of these methods will be comparatively discussed. Although at an early stage, some approaches for the assessment of the risk to mixtures of bisphenols, mainly based on the combination of chemical target analysis and toxicity evaluation, have been already applied and they will be here presented. Current knowledge gaps hindering a reliable assessment of human and environmental risk to mixtures of bisphenols and derivatives will be outlined. - Highlights: • Analytical methods for the (bio)monitoring of mixtures of bisphenols are reviewed. • LC and CG coupled to MS are the preferred techniques. • Method-dependent sample treatments are required to remove matrix

Analytical methods for the determination of mixtures of bisphenols and derivatives in human and environmental exposure sources and biological fluids. A review

Energy Technology Data Exchange (ETDEWEB)

Caballero-Casero, N.; Lunar, L.; Rubio, S., E-mail: qa1rubrs@uco.es

2016-02-18

Bisphenol A (BPA) is ubiquitous in humans and the environment. Its potential adverse effects through genomic and non-genomic pathways have fostered BPA replacement by bisphenol analogs that, unfortunately, exert similar adverse effects. Many of these analogs, as well as their derivatives, have already found in humans and the environment and major concerns have arisen over their low dose- and mixture-related effects. This review aims to discuss the characteristics of the main analytical methods reported so far for the determination of mixtures of bisphenol analogs and/or derivatives in human and environmental exposure sources and biological fluids. Approaches followed for removal of background contamination, sample preparation and separation and detection of mixtures of bisphenols and derivatives are critically discussed. Sample treatment is matrix-dependent and common steps include analyte isolation, removal of interferences, evaporation of the extracts and solvent reconstitution. Separation and quantification has been almost exclusively carried out by liquid chromatography tandem mass spectrometry (LC-MS/MS) or gas chromatography mass spectrometry (GC–MS), in the last case prior derivatization, but LC-fluorescence detection has also found some applications. Main characteristics, advantages and drawbacks of these methods will be comparatively discussed. Although at an early stage, some approaches for the assessment of the risk to mixtures of bisphenols, mainly based on the combination of chemical target analysis and toxicity evaluation, have been already applied and they will be here presented. Current knowledge gaps hindering a reliable assessment of human and environmental risk to mixtures of bisphenols and derivatives will be outlined. - Highlights: • Analytical methods for the (bio)monitoring of mixtures of bisphenols are reviewed. • LC and CG coupled to MS are the preferred techniques. • Method-dependent sample treatments are required to remove matrix

Complex mixtures, complex responses: Assessing pharmaceutical mixtures using field and laboratory approaches

Science.gov (United States)

Schoenfuss, Heiko L.; Furlong, Edward T.; Phillips, Patrick J.; Scott, Tia-Marie; Kolpin, Dana W.; Cetkovic-Cvrlje, Marina; Lesteberg, Kelsey E.; Rearick, Daniel C.

2016-01-01

Pharmaceuticals are present in low concentrations (pharmaceutical formulation facilities. Using existing concentration data, the authors assessed pharmaceuticals in laboratory exposures of fathead minnows (Pimephales promelas) and added environmental complexity through effluent exposures. In the laboratory, larval and mature minnows were exposed to a simple opioid mixture (hydrocodone, methadone, and oxycodone), an opioid agonist (tramadol), a muscle relaxant (methocarbamol), a simple antidepressant mixture (fluoxetine, paroxetine, venlafaxine), a sleep aid (temazepam), or a complex mixture of all compounds. Larval minnow response to effluent exposure was not consistent. The 2010 exposures resulted in shorter exposed minnow larvae, whereas the larvae exposed in 2012 exhibited altered escape behavior. Mature minnows exhibited altered hepatosomatic indices, with the strongest effects in females and in mixture exposures. In addition, laboratory-exposed, mature male minnows exposed to all pharmaceuticals (except the selective serotonin reuptake inhibitor mixture) defended nest sites less rigorously than fish in the control group. Tramadol or antidepressant mixture exposure resulted in increased splenic T lymphocytes. Only male minnows exposed to whole effluent responded with increased plasma vitellogenin concentrations. Female minnows exposed to pharmaceuticals (except the opioid mixture) had larger livers, likely as a compensatory result of greater prominence of vacuoles in liver hepatocytes. The observed alteration of apical endpoints central to sustaining fish populations confirms that effluents containing waste streams from pharmaceutical formulation facilities can adversely impact fish populations but that the effects may not be temporally consistent. The present study highlights the importance of including diverse biological endpoints spanning levels of biological organization and life stages when assessing contaminant interactions.

The effect of environmental parameters on contaminant uptake by a ...

African Journals Online (AJOL)

There was also no discernable relationship between pH and contaminants uptake by the sampling devices as was expected with non polar, non-ioniseable solutes. The uptake of compounds with lower molar volumes was most susceptible to the presence oh humic materials. Journal of Applied Sciences and Environmental ...

Environmental contaminants in food. Volume II-Part B: Working papers

International Nuclear Information System (INIS)

1980-01-01

This volume contains working papers written for Office of Technology Assessment (OTA) to assist in preparation of the report Environmental Contaminants in Food. The contents include: (1) Toxic substances in food information systems: design and management; (2) Assessment of carcinogenic risks from PCBs in food; (3) Economic analysis of alternative action levels in the regulation of environmental contaminants in food; (4) Analysis of foods for radioactivity; (5) Approaches to monitoring environmental contaminants in food; (6) Analytical systems for the determination of metals in food and water supplies; (7) Assessment of methods for regulating 'unavoidable' contaminants in the food supply; and (8) Consumer risk from environmental contaminants in food

Recycling of petroleum-contaminated sand.

Science.gov (United States)

Taha, R; Ba-Omar, M; Pillay, A E; Roos, G; al-Hamdi, A

2001-08-01

The environmental impact of using petroleum-contaminated sand (PCS) as a substitute in asphalt paving mixtures was examined. An appreciable component of PCS is oily sludge, which is found as the dregs in oil storage tanks and is also produced as a result of oil spills on clean sand. The current method for the disposal of oily sludge is land farming. However, this method has not been successful as an oil content of reuse of the sludge in asphalt paving mixtures was therefore considered as an alternative. Standard tests and environmental studies were conducted to establish the integrity of the materials containing the recycled sludge. These included physical and chemical characterization of the sludge itself, and an assessment of the mechanical properties of materials containing 0%, 5%, 22% and 50% oily sludge. The blended mixtures were subjected to special tests, such as Marshall testing and the determination of stability and flow properties. The experimental results indicated that mixtures containing up to 22% oily sludge could meet the necessary criteria for a specific asphalt concrete wearing course or bituminous base course. To maximize the assay from the recycled material, the environmental assessment was restricted to the 50% oily sludge mixture. Leachates associated with this particular mixture were assayed for total organic residue and certain hazardous metal contaminants. The results revealed that the organics were negligible, and the concentrations of the metals were not significant. Thus, no adverse environmental impact should be anticipated from the use of the recycled product. Our research showed that the disposal of oily sludge in asphalt paving mixtures could possibly yield considerable savings per tonne of asphalt concrete, and concurrently minimize any direct impact on the environment.

Environmental life cycle assessment of permeable reactive barriers: effects of construction methods, reactive materials and groundwater constituents.

Science.gov (United States)

Mak, Mark S H; Lo, Irene M C

2011-12-01

The effects of the construction methods, materials of reactive media and groundwater constituents on the environmental impacts of a permeable reactive barrier (PRB) were evaluated using life cycle assessment (LCA). The PRB is assumed to be installed at a simulated site contaminated by either Cr(VI) alone or Cr(VI) and As(V). Results show that the trench-based construction method can reduce the environmental impacts of the remediation remarkably compared to the caisson-based method due to less construction material consumption by the funnel. Compared to using the zerovalent iron (Fe(0)) and quartz sand mixture, the use of the Fe(0) and iron oxide-coated sand (IOCS) mixture can reduce the environmental impacts. In the presence of natural organic matter (NOM) in groundwater, the environmental impacts generated by the reactive media were significantly increased because of the higher usage of Fe(0). The environmental impacts are lower by using the Fe(0) and IOCS mixture in the groundwater with NOM, compared with using the Fe(0) and quartz sand mixture. Since IOCS can enhance the removal efficiency of Cr(VI) and As(V), the usage of the Fe(0) can be reduced, which in turn reduces the impacts induced by the reactive media.

Metal contamination in environmental media in residential ...

Science.gov (United States)

Hard-rock mining for metals, such as gold, silver, copper, zinc, iron and others, is recognized to have a significant impact on the environmental media, soil and water, in particular. Toxic contaminants released from mine waste to surface water and groundwater is the primary concern, but human exposure to soil contaminants either directly, via inhalation of airborne dust particles, or indirectly, via food chain (ingestion of animal products and/or vegetables grown in contaminated areas), is also, significant. In this research, we analyzed data collected in 2007, as part of a larger environmental study performed in the Rosia Montana area in Transylvania, to provide the Romanian governmental authorities with data on the levels of metal contamination in environmental media from this historical mining area. The data were also considered in policy decision to address mining-related environmental concerns in the area. We examined soil and water data collected from residential areas near the mining sites to determine relationships among metals analyzed in these different environmental media, using the correlation procedure in SAS statistical software. Results for residential soil and water analysis indicate that the average values for arsenic (As) (85 mg/kg), cadmium (Cd) (3.2 mg/kg), mercury (Hg) (2.3 mg/kg) and lead (Pb) (92 mg/kg) exceeded the Romanian regulatory exposure levels [the intervention thresholds for residential soil in case of As (25 mg/kg) and Hg

A multi-metric assessment of environmental contaminant exposure and effects in an urbanized reach of the Charles River near Watertown, Massachusetts

Science.gov (United States)

Smith, Stephen B.; Anderson, Patrick J.; Baumann, Paul C.; DeWeese, Lawrence R.; Goodbred, Steven L.; Coyle, James J.; Smith, David S.

2012-01-01

The Charles River Project provided an opportunity to simultaneously deploy a combination of biomonitoring techniques routinely used by the U.S. Geological Survey National Water Quality Assessment Program, the Biomonitoring of Environmental Status and Trends Project, and the Contaminant Biology Program at an urban site suspected to be contaminated with polycyclic aromatic hydrocarbons. In addition to these standardized methods, additional techniques were used to further elucidate contaminant exposure and potential impacts of exposure on biota. The purpose of the study was to generate a comprehensive, multi-metric data set to support assessment of contaminant exposure and effects at the site. Furthermore, the data set could be assessed to determine the relative performance of the standardized method suites typically used by the National Water Quality Assessment Program and the Biomonitoring of Environmental Status and Trends Project, as well as the additional biomonitoring methods used in the study to demonstrate ecological effects of contaminant exposure. The Contaminant Effects Workgroup, an advisory committee of the U.S. Geological Survey/Contaminant Biology Program, identified polycyclic aromatic hydrocarbons as the contaminant class of greatest concern in urban streams of all sizes. The reach of the Charles River near Watertown, Massachusetts, was selected as the site for this study based on the suspected presence of polycyclic aromatic hydrocarbon contamination and the presence of common carp (Cyprinus carpio), largemouth bass (Micropterus salmoides), and white sucker (Catostomus commersoni). All of these fish have extensive contaminant-exposure profiles related to polycyclic aromatic hydrocarbons and other environmental contaminants. This project represented a collaboration of universities, Department of the Interior bureaus including multiple components of the USGS (Biological Resources Discipline and Water Resources Discipline Science Centers, the

Soil sampling for environmental contaminants

International Nuclear Information System (INIS)

2004-10-01

The Consultants Meeting on Sampling Strategies, Sampling and Storage of Soil for Environmental Monitoring of Contaminants was organized by the International Atomic Energy Agency to evaluate methods for soil sampling in radionuclide monitoring and heavy metal surveys for identification of punctual contamination (hot particles) in large area surveys and screening experiments. A group of experts was invited by the IAEA to discuss and recommend methods for representative soil sampling for different kinds of environmental issues. The ultimate sinks for all kinds of contaminants dispersed within the natural environment through human activities are sediment and soil. Soil is a particularly difficult matrix for environmental pollution studies as it is generally composed of a multitude of geological and biological materials resulting from weathering and degradation, including particles of different sizes with varying surface and chemical properties. There are so many different soil types categorized according to their content of biological matter, from sandy soils to loam and peat soils, which make analytical characterization even more complicated. Soil sampling for environmental monitoring of pollutants, therefore, is still a matter of debate in the community of soil, environmental and analytical sciences. The scope of the consultants meeting included evaluating existing techniques with regard to their practicability, reliability and applicability to different purposes, developing strategies of representative soil sampling for cases not yet considered by current techniques and recommending validated techniques applicable to laboratories in developing Member States. This TECDOC includes a critical survey of existing approaches and their feasibility to be applied in developing countries. The report is valuable for radioanalytical laboratories in Member States. It would assist them in quality control and accreditation process

Protection of environmental contamination by radioactive materials and remediation of environment

International Nuclear Information System (INIS)

2003-05-01

This report consisted of the environmental contamination of radioactive and non-radioactive materials. 38 important accident examples of environmental contamination of radioactive materials in the world from 1944 to 2001 are stated. Heavily polluted areas by accidents are explained, for example, Chernobyl, atomic reactor accidents, development of nuclear weapon in USA and USSR, radioactive waste in the sea. The environmental contamination ability caused by using radioactive materials, medical use, operating reactor, disposal, transferring, crashing of airplane and artificial satellite, release are reported. It contains measurements and monitor technologies, remediation technologies of environmental contamination and separation and transmutation of radioactive materials. On the environmental contamination by non-radioactive materials, transformation of the soil contamination in Japan and its control technologies are explained. Protection and countermeasure of environmental contamination of radioactive and non-radioactive materials in Japan and the international organs are presented. There are summary and proposal in the seventh chapter. (S.Y.)

4. International Symposium and Exhibition on Environmental Contamination in Central and Eastern Europe. Symposium Program

International Nuclear Information System (INIS)

1998-01-01

The Fourth International Symposium and Exhibition on Environmental Contamination in Central and Eastern Europe was part of an on-going series of symposia which focus on the environmental problems of Central and Eastern Europe. The presentations concerned radiological contamination, hazardous waste management, environmental monitoring, modeling and computer applications for environmental studies, site remediation. Many works presented human health effects of environmental pollution by heavy metals, radionuclides and other xenobiotics

Owls as biomonitors of environmental contamination

Science.gov (United States)

Steven R. Sheffield

1997-01-01

Much like the caged canary used by miners, a plethora of wildlife species have been promoted as biomonitors of environmental contamination. These species provide an "early warning system" for toxic contaminants in the environment. Species promoted as useful biomonitors share many common life history characters, such as wide distribution, territorial, non-...

Differential effects of a complex organochlorine mixture on the proliferation of breast cancer cell lines

Energy Technology Data Exchange (ETDEWEB)

Aube, Michel, E-mail: 4aubem@videotron.ca [Axe de recherche en sante des populations et environnementale, Centre de recherche du Centre hospitalier universitaire de Quebec and Universite Laval, 2875 Boulevard Laurier, Edifice Delta 2, bureau 600, Quebec, QC, Canada G1V 2M2 (Canada); Larochelle, Christian, E-mail: christian.larochelle@inspq.qc.ca [Axe de recherche en sante des populations et environnementale, Centre de recherche du Centre hospitalier universitaire de Quebec and Universite Laval, 2875 Boulevard Laurier, Edifice Delta 2, bureau 600, Quebec, QC, Canada G1V 2M2 (Canada); Ayotte, Pierre, E-mail: pierre.ayotte@inspq.qc.ca [Axe de recherche en sante des populations et environnementale, Centre de recherche du Centre hospitalier universitaire de Quebec and Universite Laval, 2875 Boulevard Laurier, Edifice Delta 2, bureau 600, Quebec, QC, Canada G1V 2M2 (Canada); Laboratoire de Toxicologie, Institut national de sante publique du Quebec, 945 avenue Wolfe, Quebec, QC, Canada G1V 5B3 (Canada)

2011-04-15

Organochlorine compounds (OCs) are a group of persistent chemicals that accumulate in fatty tissues with age. Although OCs has been tested individually for their capacity to induce breast cancer cell proliferation, few studies examined the effect of complex mixtures that comprise compounds frequently detected in the serum of women. We constituted such an OC mixture containing 15 different components in environmentally relevant proportions and assessed its proliferative effects in four breast cancer cell lines (MCF-7, T47D, CAMA-1, MDAMB231) and in non-cancerous CV-1 cells. We also determined the capacity of the mixture to modulate cell cycle stage of breast cancer cells and to induce estrogenic and antiandrogenic effects using gene reporter assays. We observed that low concentrations of the mixture (100x10{sup 3} and 50x10{sup 3} dilutions) stimulated the proliferation of MCF-7 cells while higher concentrations (10x10{sup 3} and 5x10{sup 3} dilutions) had the opposite effect. In contrast, the mixture inhibited the proliferation of non-hormone-dependent cell lines. The mixture significantly increased the number of MCF-7 cells entering the S phase, an effect that was blocked by the antiestrogen ICI 182,780. Low concentrations of the mixture also caused an increase in CAMA-1 cell proliferation but only in the presence estradiol and dihydrotestosterone (p<0.05 at the 50x10{sup 3} dilution). DDT analogs and polychlorinated biphenyls all had the capacity to stimulate the proliferation of CAMA-1 cells in the presence of sex steroids. Reporter gene assays further revealed that the mixture and several of its constituents (DDT analogs, aldrin, dieldrin, {beta}-hexachlorocyclohexane, toxaphene) induced estrogenic effects, whereas the mixture and several components (DDT analogs, aldrin, dieldrin and PCBs) inhibited the androgen signaling pathway. Our results indicate that the complex OC mixture increases the proliferation of MCF-7 cells due to its estrogenic potential. The

Environmental contamination, product contamination and workers exposure using a robotic system for antineoplastic drug preparation.

Science.gov (United States)

Sessink, Paul J M; Leclercq, Gisèle M; Wouters, Dominique-Marie; Halbardier, Loïc; Hammad, Chaïma; Kassoul, Nassima

2015-04-01

Environmental contamination, product contamination and technicians exposure were measured following preparation of iv bags with cyclophosphamide using the robotic system CytoCare. Wipe samples were taken inside CytoCare, in the clean room environment, from vials, and prepared iv bags including ports and analysed for contamination with cyclophosphamide. Contamination with cyclophosphamide was also measured in environmental air and on the technicians hands and gloves used for handling the drugs. Exposure of the technicians to cyclophosphamide was measured by analysis of cyclophosphamide in urine. Contamination with cyclophosphamide was mainly observed inside CytoCare, before preparation, after preparation and after daily routine cleaning. Contamination outside CytoCare was incidentally found. All vials with reconstituted cyclophosphamide entering CytoCare were contaminated on the outside but vials with powdered cyclophosphamide were not contaminated on the outside. Contaminated bags entering CytoCare were also contaminated after preparation but non-contaminated bags were not contaminated after preparation. Cyclophosphamide was detected on the ports of all prepared bags. Almost all outer pairs of gloves used for preparation and daily routine cleaning were contaminated with cyclophosphamide. Cyclophosphamide was not found on the inner pairs of gloves and on the hands of the technicians. Cyclophosphamide was not detected in the stationary and personal air samples and in the urine samples of the technicians. CytoCare enables the preparation of cyclophosphamide with low levels of environmental contamination and product contamination and no measurable exposure of the technicians. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Evaluating the environmental consequences of groundwater contamination. IV. Obtaining and utilizing contaminant arrival distributions in transient flow systems

International Nuclear Information System (INIS)

Nelson, R.W.

1978-01-01

The versatility of the new contaminant arrival distributions for determining environmental consequences of subsurface pollution problems is demonstrated through application to a transient flow system. Though some of the four phases of the hydrologic evaluations are more complicated because of the time dependence of the flow and input contaminant concentrations, the arrival distributions still effectively summarize the data required to determine the environmental implications. These arrival distributions yield two graphs or tabular sets of data giving the consequences of the subsurface pollution problems in a simple and direct form. 4 refs

Indoor Environmental Contaminants in Schools

Science.gov (United States)

A wide range of environmental contaminants can affect the health and safety of a school environment. This page covers the basics on issues your school may face, including asbestos, chemicals, formaldehyde, lead, mercury, PCBs and radon.

Application of Biologically-Based Lumping To Investigate the Toxicological Interactions of a Complex Gasoline Mixture

Science.gov (United States)

People are often exposed to complex mixtures of environmental chemicals such as gasoline, tobacco smoke, water contaminants, or food additives. However, investigators have often considered complex mixtures as one lumped entity. Valuable information can be obtained from these exp...

Generic Escherichia coli contamination of spinach at the preharvest stage: effects of farm management and environmental factors.

Science.gov (United States)

Park, Sangshin; Navratil, Sarah; Gregory, Ashley; Bauer, Arin; Srinath, Indumathi; Jun, Mikyoung; Szonyi, Barbara; Nightingale, Kendra; Anciso, Juan; Ivanek, Renata

2013-07-01

The objective of this study was to determine the effects of farm management and environmental factors on preharvest spinach contamination with generic Escherichia coli as an indicator of fecal contamination. A repeated cross-sectional study was conducted by visiting spinach farms up to four times per growing season over a period of 2 years (2010 to 2011). Spinach samples (n = 955) were collected from 12 spinach farms in Colorado and Texas as representative states of the Western and Southwestern United States, respectively. During each farm visit, farmers were surveyed about farm-related management and environmental factors using a questionnaire. Associations between the prevalence of generic E. coli in spinach and farm-related factors were assessed by using a multivariable logistic regression model including random effects for farm and farm visit. Overall, 6.6% of spinach samples were positive for generic E. coli. Significant risk factors for spinach contamination with generic E. coli were the proximity (within 10 miles) of a poultry farm, the use of pond water for irrigation, a >66-day period since the planting of spinach, farming on fields previously used for grazing, the production of hay before spinach planting, and the farm location in the Southwestern United States. Contamination with generic E. coli was significantly reduced with an irrigation lapse time of >5 days as well as by several factors related to field workers, including the use of portable toilets, training to use portable toilets, and the use of hand-washing stations. To our knowledge, this is the first report of an association between field workers' personal hygiene and produce contamination with generic E. coli at the preharvest level. Collectively, our findings support that practice of good personal hygiene and other good farm management practices may reduce produce contamination with generic E. coli at the preharvest level.

Generic Escherichia coli Contamination of Spinach at the Preharvest Stage: Effects of Farm Management and Environmental Factors

Science.gov (United States)

Navratil, Sarah; Gregory, Ashley; Bauer, Arin; Srinath, Indumathi; Jun, Mikyoung; Szonyi, Barbara; Nightingale, Kendra; Anciso, Juan; Ivanek, Renata

2013-01-01

The objective of this study was to determine the effects of farm management and environmental factors on preharvest spinach contamination with generic Escherichia coli as an indicator of fecal contamination. A repeated cross-sectional study was conducted by visiting spinach farms up to four times per growing season over a period of 2 years (2010 to 2011). Spinach samples (n = 955) were collected from 12 spinach farms in Colorado and Texas as representative states of the Western and Southwestern United States, respectively. During each farm visit, farmers were surveyed about farm-related management and environmental factors using a questionnaire. Associations between the prevalence of generic E. coli in spinach and farm-related factors were assessed by using a multivariable logistic regression model including random effects for farm and farm visit. Overall, 6.6% of spinach samples were positive for generic E. coli. Significant risk factors for spinach contamination with generic E. coli were the proximity (within 10 miles) of a poultry farm, the use of pond water for irrigation, a >66-day period since the planting of spinach, farming on fields previously used for grazing, the production of hay before spinach planting, and the farm location in the Southwestern United States. Contamination with generic E. coli was significantly reduced with an irrigation lapse time of >5 days as well as by several factors related to field workers, including the use of portable toilets, training to use portable toilets, and the use of hand-washing stations. To our knowledge, this is the first report of an association between field workers' personal hygiene and produce contamination with generic E. coli at the preharvest level. Collectively, our findings support that practice of good personal hygiene and other good farm management practices may reduce produce contamination with generic E. coli at the preharvest level. PMID:23666336

Symposium on Short-Term Genetic Bioassays in the Evaluation of Complex Environmental Mixtures

CERN Document Server

Sandhu, Shahbeg; Lewtas, Joellen; Claxton, Larry; Strauss, Gary; Nesnow, Stephen

1985-01-01

With this proceedings of the fourth symposium on complex mixtures, we continue to revise and extend our knowledge of genetic methods for the evaluation of chemical mixtures in the environment. The early chapters of this volume are devoted to new bioassay techniques that are directly applicable to the monitoring of environments contaminated with genotoxic chemicals. Microbiological methods have been further refined to meet the special needs of atmospheric monitoring so that very small samples may now be efficiently tested. New in situ methods utilizing green plants actually avoid many of the usual difficulties of sample collection and preparation and offer special advantages in monitoring wastewater, sludges, and hazardous wastes. Insects also are being employed very effectively in the evaluation of gaseous air pollutants in controlled laboratory investigations. Increased emphasis has been placed on a comprehensive assessment of the potential of complex mixtures t9 cause various kinds of genetic damage. New as...

Combined effect of radiation and environmental contaminants on DNA repair mechanisms

International Nuclear Information System (INIS)

Altmann, H.

1975-11-01

Investigations on the influence of various environmental contamination agents on DNA repair (in combination with irradiation) were reviewed. The agents tested were: detergents (Tween 80, Nonidel P40, Cremophor), aflatoxin B 1 , furocumarines, drugs (indometacin, cyclophosphamide, vincristine, vinblastine, procarbacine), fluorides, irradiated food constituents, food additives (saccharin), metal ions (Cd, Hg), pesticides (2,4,5-trichlorophenoxyethanol) and infective agents (mycoplasmas). Most of the tests were carried out in vitro with γ-irradiated mouse spleen cells. The detergents and aflatoxin were tested also on E. coli, and irradiated glucose solutions were tested in vivo on Swiss albino mice injected with Salmonella typhimurium TA 1530. Most of the tested agents showed some kind of inhibitory or mutagenic effect. The experiments and results are explained briefly with references to earlier investigations

Effects of an Environmentally-relevant Mixture of Pyrethroid Insecticides on Spontaneous Activity in Primary Cortical Networks on Microelectrode Arrays

Data.gov (United States)

U.S. Environmental Protection Agency — This manuscript tests the hypothesis of dose additivity of an environmental mixture of pyrethriod insecticides at the level of network function, in vitro. The...

Ecological aspects of environmental assessment of contaminated areas

International Nuclear Information System (INIS)

Templeton, W.L.

1990-04-01

When large landscapes are contaminated by radionuclides released from nuclear activities, physical processes, such as atmospheric and hydrological transport may move the radioactive materials over large distances resulting in direct external exposure of man and organisms. This paper provides an overview of the modeling of radionuclide movement through defined ecological pathways, describes some ecological problems at remediated sites, and briefly reviews effects of environmental radiation on terrestrial and aquatic biota. This paper describes pathways that should be considered when conducting environmental dose assessments for radionuclides released to the environment. 4 refs

Alcohol, drugs, caffeine, tobacco, and environmental contaminant exposure: reproductive health consequences and clinical implications.

Science.gov (United States)

Sadeu, J C; Hughes, Claude L; Agarwal, Sanjay; Foster, Warren G

2010-08-01

Reproductive function and fertility are thought to be compromised by behaviors such as cigarette smoking, substance abuse, and alcohol consumption; however, the strength of these associations are uncertain. Furthermore, the reproductive system is thought to be under attack from exposure to environmental contaminants, particularly those chemicals shown to affect endocrine homeostasis. The relationship between exposure to environmental contaminants and adverse effects on human reproductive health are frequently debated in the scientific literature and these controversies have spread into the lay press drawing increased public and regulatory attention. Therefore, the objective of the present review was to critically evaluate the literature concerning the relationship between lifestyle exposures and adverse effects on fertility as well as examining the evidence for a role of environmental contaminants in the purported decline of semen quality and the pathophysiology of subfertility, polycystic ovarian syndrome, and endometriosis. The authors conclude that whereas cigarette smoking is strongly associated with adverse reproductive outcomes, high-level exposures to other lifestyle factors are only weakly linked with negative fertility impacts. Finally, there is no compelling evidence that environmental contaminants, at concentrations representative of the levels measured in contemporary biomonitoring studies, have any effect, positive or negative, on reproductive health in the general population. Further research using prospective study designs with robust sample sizes are needed to evaluate testable hypotheses that address the relationship between exposure and adverse reproductive health effects.

Overview of Emerging Contaminants and Associated Human Health Effects

Science.gov (United States)

Lei, Meng; Zhang, Lun; Lei, Jianjun; Zong, Liang; Li, Jiahui; Wu, Zheng; Wang, Zheng

2015-01-01

In recent decades, because of significant progress in the analysis and detection of trace pollutants, emerging contaminants have been discovered and quantified in living beings and diverse environmental substances; however, the adverse effects of environmental exposure on the general population are largely unknown. This review summarizes the conclusions of the comprehensive epidemic literature and representative case reports relevant to emerging contaminants and the human body to address concerns about potential harmful health effects in the general population. The most prevalent emerging contaminants include perfluorinated compounds, water disinfection byproducts, gasoline additives, manufactured nanomaterials, human and veterinary pharmaceuticals, and UV-filters. Rare but statistically meaningful connections have been reported for a number of contaminants and cancer and reproductive risks. Because of contradictions in the outcomes of some investigations and the limited number of articles, no significant conclusions regarding the relationship between adverse effects on humans and extents of exposure can be drawn at this time. Here, we report that the current evidence is not conclusive and comprehensive and suggest prospective cohort studies in the future to evaluate the associations between human health outcomes and emerging environmental contaminants. PMID:26713315

Overview of Emerging Contaminants and Associated Human Health Effects

Directory of Open Access Journals (Sweden)

Meng Lei

2015-01-01

Full Text Available In recent decades, because of significant progress in the analysis and detection of trace pollutants, emerging contaminants have been discovered and quantified in living beings and diverse environmental substances; however, the adverse effects of environmental exposure on the general population are largely unknown. This review summarizes the conclusions of the comprehensive epidemic literature and representative case reports relevant to emerging contaminants and the human body to address concerns about potential harmful health effects in the general population. The most prevalent emerging contaminants include perfluorinated compounds, water disinfection byproducts, gasoline additives, manufactured nanomaterials, human and veterinary pharmaceuticals, and UV-filters. Rare but statistically meaningful connections have been reported for a number of contaminants and cancer and reproductive risks. Because of contradictions in the outcomes of some investigations and the limited number of articles, no significant conclusions regarding the relationship between adverse effects on humans and extents of exposure can be drawn at this time. Here, we report that the current evidence is not conclusive and comprehensive and suggest prospective cohort studies in the future to evaluate the associations between human health outcomes and emerging environmental contaminants.

Prospective environmental risk assessment of mixtures in wastewater treatment plant effluents - Theoretical considerations and experimental verification.

Science.gov (United States)

Coors, Anja; Vollmar, Pia; Sacher, Frank; Polleichtner, Christian; Hassold, Enken; Gildemeister, Daniela; Kühnen, Ute

2018-04-14

The aquatic environment is continually exposed to a complex mixture of chemicals, whereby effluents of wastewater treatment plants (WWTPs) are one key source. The aim of the present study was to investigate whether environmental risk assessments (ERAs) addressing individual substances are sufficiently protective for such coincidental mixtures. Based on a literature review of chemicals reported to occur in municipal WWTP effluents and mode-of-action considerations, four different types of mixtures were composed containing human pharmaceuticals, pesticides, and chemicals regulated under REACH. The experimentally determined chronic aquatic toxicity of these mixtures towards primary producers and the invertebrate Daphnia magna could be adequately predicted by the concept of concentration addition, with up to 5-fold overestimation and less than 3-fold underestimation of mixture toxicity. Effluents of a municipal WWTP had no impact on the predictability of mixture toxicity and showed no adverse effects on the test organisms. Predictive ERAs for the individual mixture components based on here derived predicted no effect concentrations (PNECs) and median measured concentrations in WWTP effluents (MC eff ) indicated no unacceptable risk for any of the individual chemicals, while MC eff /PNEC summation indicated a possible risk for multi-component mixtures. However, a refined mixture assessment based on the sum of toxic units at species level indicated no unacceptable risks, and allowed for a safety margin of more than factor 10, not taking into account any dilution of WWTP effluents by surface waters. Individual substances, namely climbazole, fenofibric acid and fluoxetine, were dominating the risks of the investigated mixtures, while added risk due to the mixture was found to be low with the risk quotient being increased by less than factor 2. Yet, uncertainty remains regarding chronic mixture toxicity in fish, which was not included in the present study. The number and

Environmental radioactive contamination and its control for nuclear power plants

International Nuclear Information System (INIS)

Shi Zhongqi; Qu Jingyuan; Cui Yongli

1998-01-01

The environmental radioactive releases and exposure to human being due to operation of nuclear power plants in the world and in China, environmental contamination and consequences caused by severe nuclear power plant accidents in the history, control of the radioactive contamination in China, and some nuclear laws on the radioactive contamination control established by international organizations and USA etc. are described according to literature investigation and research. Some problems and comments in radioactive contamination control for nuclear power plants in China are presented. Therefore, perfecting laws and regulations and enhancing surveillances on the contamination control are recommended

Effects of anthropogenic heavy metal contamination on litter decomposition in streams – A meta-analysis

International Nuclear Information System (INIS)

Ferreira, Verónica; Koricheva, Julia; Duarte, Sofia; Niyogi, Dev K.; Guérold, François

2016-01-01

Many streams worldwide are affected by heavy metal contamination, mostly due to past and present mining activities. Here we present a meta-analysis of 38 studies (reporting 133 cases) published between 1978 and 2014 that reported the effects of heavy metal contamination on the decomposition of terrestrial litter in running waters. Overall, heavy metal contamination significantly inhibited litter decomposition. The effect was stronger for laboratory than for field studies, likely due to better control of confounding variables in the former, antagonistic interactions between metals and other environmental variables in the latter or differences in metal identity and concentration between studies. For laboratory studies, only copper + zinc mixtures significantly inhibited litter decomposition, while no significant effects were found for silver, aluminum, cadmium or zinc considered individually. For field studies, coal and metal mine drainage strongly inhibited litter decomposition, while drainage from motorways had no significant effects. The effect of coal mine drainage did not depend on drainage pH. Coal mine drainage negatively affected leaf litter decomposition independently of leaf litter identity; no significant effect was found for wood decomposition, but sample size was low. Considering metal mine drainage, arsenic mines had a stronger negative effect on leaf litter decomposition than gold or pyrite mines. Metal mine drainage significantly inhibited leaf litter decomposition driven by both microbes and invertebrates, independently of leaf litter identity; no significant effect was found for microbially driven decomposition, but sample size was low. Overall, mine drainage negatively affects leaf litter decomposition, likely through negative effects on invertebrates. - Highlights: • A meta-analysis was done to assess the effects of heavy metals on litter decomposition. • Heavy metals significantly and strongly inhibited litter decomposition in streams. �

Environmental radioactive contamination

International Nuclear Information System (INIS)

Saucedo, Edgardo

2000-01-01

The environmental radioactive contamination with the scientific and technological advances can produce big benefits or damages to the human beings or the environment. The approval of national or international laws in the population's education so that it can face the topic critically and the scientific formation of human resources and ethically for application of the ionizing radiations, they are the best road to take advantage to the maximum of benefits of these radiations, reducing to the minimum the risks on the man and the environment

Mixture toxicity of flubendazole and fenbendazole to Daphnia magna.

Science.gov (United States)

Puckowski, Alan; Stolte, Stefan; Wagil, Marta; Markiewicz, Marta; Łukaszewicz, Paulina; Stepnowski, Piotr; Białk-Bielińska, Anna

2017-05-01

Nowadays, residual amounts of many pharmaceuticals can be found in various environmental compartments including surface and ground waters, soils and sediments as well as biota. Even though they undergo degradability, their environmental discharge is relatively continuous, thus they may be regarded as quasi-persistent contaminants, and are also frequently regarded as emerging organic pollutants. Benzimidazoles, especially flubendazole (FLU) and fenbendazole (FEN), represent two anthelmintic drugs belonging to this group. Although their presence in environmental matrices has been reported, there is relatively little data concerning their (eco)toxicological impact. Furthermore, no data is available on their mixture toxicity. FLU and FEN have been found to have a strong impact on an environmentally important non-target organism - Daphnia magna. Moreover, these compounds are usually present in the environment as a part of pharmaceutical mixtures. Therefore, there is a need to evaluate their mixture toxicity, which was the main aim of this study. Single substance toxicity tests were carried out in parallel with mixture studies of FLU and FEN, with the application of two well established concepts of Concentration Addition (CA) and Independent Action (IA). As a result, both models (CA and IA) were found to underestimate the toxicity of mixtures, however CA yielded more accurate predictions. Copyright © 2017 Elsevier GmbH. All rights reserved.

Simultaneous biodegradation of volatile and toxic contaminant mixtures by solid–liquid two-phase partitioning bioreactors

Energy Technology Data Exchange (ETDEWEB)

Poleo, Eduardo E.; Daugulis, Andrew J., E-mail: andrew.daugulis@chee.queensu.ca

2013-06-15

Highlights: • We investigate the simultaneous biodegradation of phenol and butyl acetate. • We identify an effective polymer mixture to selectively absorb each of the substrates and decrease their initial concentration. •The polymer mixture is used to overcome the high phenol cytotoxicity and reduce the abiotic losses of butyl acetate associated with volatility. • The solid–liquid Two Phase Partitioning Bioreactor (TPPB) outperforms the liquid–liquid TPPB and the single phase systems. -- Abstract: Microbial inhibition and stripping of volatile compounds are two common problems encountered in the biotreatment of contaminated wastewaters. Both can be addressed by the addition of a hydrophobic auxiliary phase that can absorb and subsequently re-release the substrates, lowering their initial aqueous concentrations. Such systems have been described as Two Phase Partitioning Bioreactors (TPPBs). In the current work the performances of a solid–liquid TPPB, a liquid–liquid TPPB and a single phase reactor for the simultaneous degradation of butyl acetate (the volatile component) and phenol (the toxic component) have been compared. The auxiliary phase used in the solid–liquid TPPB was a 50:50 polymer mixture of styrene–butadiene rubber and Hytrel{sup ®} 8206, with high affinities for butyl acetate and phenol, respectively. The liquid–liquid TPPB employed silicone oil which has fixed physical properties, and had no capacity to absorb the toxic contaminant (phenol). Butyl acetate degradation was enhanced in both TPPBs relative to the single phase, arising from its sequestration into the auxiliary phase, thereby reducing volatilization losses. The solid–liquid TPPB additionally showed a substantial increase in the phenol degradation rate, relative to the silicone oil system, demonstrating the superiority and versatility of polymer based systems.

A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach for contaminated sites management

Energy Technology Data Exchange (ETDEWEB)

Hu, Yan; Wen, Jing-ya; Li, Xiao-li; Wang, Da-zhou; Li, Yu, E-mail: liyuxx8@hotmail.com

2013-10-15

Highlights: • Using interval mathematics to describe spatial and temporal variability and parameter uncertainty. • Using fuzzy theory to quantify variability of environmental guideline values. • Using probabilistic approach to integrate interval concentrations and fuzzy environmental guideline. • Establishment of dynamic multimedia environmental integrated risk assessment framework. -- Abstract: A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach was developed for contaminated sites management. The contaminant concentrations were simulated by a validated interval dynamic multimedia fugacity model, and different guideline values for the same contaminant were represented as a fuzzy environmental guideline. Then, the probability of violating environmental guideline (Pv) can be determined by comparison between the modeled concentrations and the fuzzy environmental guideline, and the constructed relationship between the Pvs and environmental risk levels was used to assess the environmental risk level. The developed approach was applied to assess the integrated environmental risk at a case study site in China, simulated from 1985 to 2020. Four scenarios were analyzed, including “residential land” and “industrial land” environmental guidelines under “strict” and “loose” strictness. It was found that PAH concentrations will increase steadily over time, with soil found to be the dominant sink. Source emission in soil was the leading input and atmospheric sedimentation was the dominant transfer process. The integrated environmental risks primarily resulted from petroleum spills and coke ovens, while the soil environmental risks came from coal combustion. The developed approach offers an effective tool for quantifying variability and uncertainty in the dynamic multimedia integrated environmental risk assessment and the contaminated site management.

A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach for contaminated sites management

International Nuclear Information System (INIS)

Hu, Yan; Wen, Jing-ya; Li, Xiao-li; Wang, Da-zhou; Li, Yu

2013-01-01

Highlights: • Using interval mathematics to describe spatial and temporal variability and parameter uncertainty. • Using fuzzy theory to quantify variability of environmental guideline values. • Using probabilistic approach to integrate interval concentrations and fuzzy environmental guideline. • Establishment of dynamic multimedia environmental integrated risk assessment framework. -- Abstract: A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach was developed for contaminated sites management. The contaminant concentrations were simulated by a validated interval dynamic multimedia fugacity model, and different guideline values for the same contaminant were represented as a fuzzy environmental guideline. Then, the probability of violating environmental guideline (Pv) can be determined by comparison between the modeled concentrations and the fuzzy environmental guideline, and the constructed relationship between the Pvs and environmental risk levels was used to assess the environmental risk level. The developed approach was applied to assess the integrated environmental risk at a case study site in China, simulated from 1985 to 2020. Four scenarios were analyzed, including “residential land” and “industrial land” environmental guidelines under “strict” and “loose” strictness. It was found that PAH concentrations will increase steadily over time, with soil found to be the dominant sink. Source emission in soil was the leading input and atmospheric sedimentation was the dominant transfer process. The integrated environmental risks primarily resulted from petroleum spills and coke ovens, while the soil environmental risks came from coal combustion. The developed approach offers an effective tool for quantifying variability and uncertainty in the dynamic multimedia integrated environmental risk assessment and the contaminated site management

Environmental Contamination of Normal Speech.

Science.gov (United States)

Harley, Trevor A.

1990-01-01

Environmentally contaminated speech errors (irrelevant words or phrases derived from the speaker's environment and erroneously incorporated into speech) are hypothesized to occur at a high level of speech processing, but with a relatively late insertion point. The data indicate that speech production processes are not independent of other…

Children's Exposure to Environmental Contaminants: An Editorial Reflection of Articles in the IJERPH Special Issue Entitled, "Children's Exposure to Environmental Contaminants".

Science.gov (United States)

Ferguson, Alesia; Solo-Gabriele, Helena

2016-11-09

Children are at increased vulnerability to many environmental contaminants compared to adults due to their unique behavior patterns, increased contaminant intake per body weight, and developing biological systems. Depending upon their age, young children may crawl on the floor and may practice increased hand to mouth activity that may increase their dose-intake of specific contaminants that accumulate in dust and other matrices. Children are also smaller in size than adults, resulting in a greater body burden for a given contaminant dose. Because children undergo rapid transitions through particular developmental stages they are also especially vulnerable during certain growth-related time windows. A Special Issue was organized focused on the latest findings in the field of children's environmental exposure for these reasons. This editorial introduces articles in this Special Issue and emphasizes their main findings in advancing the field. From the many articles submitted to this Special Issue from around the world, 23 were accepted and published. They focus on a variety of research areas such as children's activity patterns, improved risk assessment methods to estimate exposures, and exposures in various contexts and to various contaminants. The future health of a nation relies on protecting the children from adverse exposures and understanding the etiology of childhood diseases. The field of children's environmental exposures must consider improved and comprehensive research methods aimed at introducing mitigation strategies locally, nationally, and globally. We are happy to introduce a Special Issue focused on children's environmental exposure and children's health and hope that it contributes towards improved health of children.

Technical guidelines for environmental dredging of contaminated sediments

Science.gov (United States)

2008-09-01

This report provides technical guidelines for evaluating : environmental dredging as a sediment remedy component. This document : supports the Contaminated Sediment Remediation Guidance for : Hazardous Waste Sites, released by the U.S. Environmental ...

Prenatal exposure to an environmentally relevant phthalate mixture disrupts reproduction in F1 female mice

Energy Technology Data Exchange (ETDEWEB)

Zhou, Changqing; Gao, Liying; Flaws, Jodi A., E-mail: jflaws@illinois.edu

2017-03-01

Phthalates are used in a large variety of products, such as building materials, medical devices, and personal care products. Most previous studies on the toxicity of phthalates have focused on single phthalates, but it is also important to study the effects of phthalate mixtures because humans are exposed to phthalate mixtures. Thus, we tested the hypothesis that prenatal exposure to an environmentally relevant phthalate mixture adversely affects female reproduction in mice. To test this hypothesis, pregnant CD-1 dams were orally dosed with vehicle (tocopherol-stripped corn oil) or a phthalate mixture (20 and 200 μg/kg/day, 200 and 500 mg/kg/day) daily from gestational day 10 to birth. The mixture was based on the composition of phthalates detected in urine samples from pregnant women in Illinois. The mixture included 35% diethyl phthalate, 21% di(2-ethylhexyl) phthalate, 15% dibutyl phthalate, 15% diisononyl phthalate, 8% diisobutyl phthalate, and 5% benzylbutyl phthalate. Female mice born to the exposed dams were subjected to tissue collections and fertility tests at different ages. Our results indicate that prenatal exposure to the phthalate mixture significantly increased uterine weight and decreased anogenital distance on postnatal days 8 and 60, induced cystic ovaries at 13 months, disrupted estrous cyclicity, reduced fertility-related indices, and caused some breeding complications at 3, 6, and 9 months of age. Collectively, our data suggest that prenatal exposure to an environmentally relevant phthalate mixture disrupts aspects of female reproduction in mice. - Highlights: • Prenatal exposure to a phthalate mixture disrupts F1 estrous cyclicity. • Prenatal exposure to a phthalate mixture induces F1 ovarian cysts. • Prenatal exposure to a phthalate mixture decreases F1 female fertility-related indices. • Prenatal exposure to a phthalate mixture induces F1 breeding complications.

Mussel as biomonitor of environmental contamination

International Nuclear Information System (INIS)

Souza, Vivianne L.B.; Nascimento, Rizia Keila do; Melo, Jessica V. de

2013-01-01

The presence of agricultural input, domestic and industrial discharges, can result in a contaminant impact in aquatic ecosystems and in elevated concentrations of trace metals that may exert direct toxic effects and maybe accumulated in organisms consumed by man. The objective of the present study was to investigate some metal concentrations in Mytilidae falcate collected from Channel of Santa Cruz, Brazil. There are some industries located along the Channel of Santa Cruz that manufacture aluminum, paper and cellulose, pesticides, and caustic soda. Mussels collected at this area were carefully opened, dried and 0.5g of samples were heating with a mixture of acids; the final solution was filtered and made up to 50 mL. Metals concentrations were measured at aICP-MS (FINNIGAN) and AAS (VARIAN). The results demonstrated that there is more Fe and Mn in the mussels than any other studied metals (Fe >Mn >Cd >Pb >Cu >Th >U).The results for Fe and Mn concentrations are similar to those reported in the literature for invertebrates and fishes collected in regions contaminated by domestic and industrial sewage. Lead and Cd values, on the other hand, are beyond the limiting values for human consumption. Only the levels of copper are within to the Brazilian legislation. Uranium concentration was lower than results showed in literature. (author)

Mussel as biomonitor of environmental contamination

Energy Technology Data Exchange (ETDEWEB)

Souza, Vivianne L.B.; Nascimento, Rizia Keila do, E-mail: vlsouza@cnen.gov.br, E-mail: riziakelia@hotmail.com [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Melo, Jessica V. de, E-mail: jessica_clorofila@hotmail [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

2013-07-01

The presence of agricultural input, domestic and industrial discharges, can result in a contaminant impact in aquatic ecosystems and in elevated concentrations of trace metals that may exert direct toxic effects and maybe accumulated in organisms consumed by man. The objective of the present study was to investigate some metal concentrations in Mytilidae falcate collected from Channel of Santa Cruz, Brazil. There are some industries located along the Channel of Santa Cruz that manufacture aluminum, paper and cellulose, pesticides, and caustic soda. Mussels collected at this area were carefully opened, dried and 0.5g of samples were heating with a mixture of acids; the final solution was filtered and made up to 50 mL. Metals concentrations were measured at aICP-MS (FINNIGAN) and AAS (VARIAN). The results demonstrated that there is more Fe and Mn in the mussels than any other studied metals (Fe >Mn >Cd >Pb >Cu >Th >U).The results for Fe and Mn concentrations are similar to those reported in the literature for invertebrates and fishes collected in regions contaminated by domestic and industrial sewage. Lead and Cd values, on the other hand, are beyond the limiting values for human consumption. Only the levels of copper are within to the Brazilian legislation. Uranium concentration was lower than results showed in literature. (author)

Pharmaceuticals, hormones, personal-care products, and other organic wastewater contaminants in water resources: Recent research activities of the U.S. Geological Survey's toxic substances hydrology program

Science.gov (United States)

Focazio, Michael J.; Kolpin, Dana W.; Buxton, Herbert T.

2003-01-01

Recent decades have brought increasing concerns for potential contamination of water resources that could inadvertently result during production, use, and disposal of the numerous chemicals offering improvements in industry, agriculture, medical treatment, and even common household products. Increasing knowledge of the environmental occurrence or toxicological behavior of these contaminants from various studies in Europe, United States, and elsewhere has resulted in increased concern for potential adverse environmental and human health effects (Daughton and Ternes, 1999). Ecologists and public health experts often have incomplete understandings of the toxicological significance of many of these contaminants, particularly long-term, low-level exposure and when they occur in mixtures with other contaminants (Daughton and Ternes, 1999; Kümmerer, 2001). In addition, these ‘emerging contaminants’ are not typically monitored or assessed in ambient water resources. The need to understand the processes controlling the transport and fate of these contaminants in the environment, and the lack of knowledge of the significance of long-term exposures have increased the need to study environmental occurrence down to trace (nanogram per liter) levels. Furthermore, the possibility that mixtures of environmental contaminants may interact synergistically or antagonistically has increased the need to characterize the types of mixtures that are found in our waters. The U.S. Geological Survey’s Toxic Substances Hydrology Program (Toxics Program) is developing information and tools on emerging water-quality issues that will be used to design and improve water-quality monitoring and assessment programs of the USGS and others, and for proactive decision-making by industry, regulators, the research community, and the public (http://toxics.usgs.gov/regional/emc.html). This research on emerging water-quality issues includes a combination of laboratory work to develop new analytical

Quantifying synergy: a systematic review of mixture toxicity studies within environmental toxicology.

Directory of Open Access Journals (Sweden)

Nina Cedergreen

Full Text Available Cocktail effects and synergistic interactions of chemicals in mixtures are an area of great concern to both the public and regulatory authorities. The main concern is whether some chemicals can enhance the effect of other chemicals, so that they jointly exert a larger effect than predicted. This phenomenon is called synergy. Here we present a review of the scientific literature on three main groups of environmentally relevant chemical toxicants: pesticides, metal ions and antifouling compounds. The aim of the review is to determine 1 the frequency of synergy, 2 the extent of synergy, 3 whether any particular groups or classes of chemicals tend to induce synergy, and 4 which physiological mechanisms might be responsible for this synergy. Synergy is here defined as mixtures with minimum two-fold difference between observed and predicted effect concentrations using Concentration Addition (CA as a reference model and including both lethal and sub-lethal endpoints. The results showed that synergy occurred in 7%, 3% and 26% of the 194, 21 and 136 binary pesticide, metal and antifoulants mixtures included in the data compilation on frequency. The difference between observed and predicted effect concentrations was rarely more than 10-fold. For pesticides, synergistic mixtures included cholinesterase inhibitors or azole fungicides in 95% of 69 described cases. Both groups of pesticides are known to interfere with metabolic degradation of other xenobiotics. For the four synergistic metal and 47 synergistic antifoulant mixtures the pattern in terms of chemical groups inducing synergy was less clear. Hypotheses in terms of mechanisms governing these interactions are discussed. It was concluded that true synergistic interactions between chemicals are rare and often occur at high concentrations. Addressing the cumulative rather than synergistic effect of co-occurring chemicals, using standard models as CA, is therefore regarded as the most important step in

Quantifying synergy: a systematic review of mixture toxicity studies within environmental toxicology.

Science.gov (United States)

Cedergreen, Nina

2014-01-01

Cocktail effects and synergistic interactions of chemicals in mixtures are an area of great concern to both the public and regulatory authorities. The main concern is whether some chemicals can enhance the effect of other chemicals, so that they jointly exert a larger effect than predicted. This phenomenon is called synergy. Here we present a review of the scientific literature on three main groups of environmentally relevant chemical toxicants: pesticides, metal ions and antifouling compounds. The aim of the review is to determine 1) the frequency of synergy, 2) the extent of synergy, 3) whether any particular groups or classes of chemicals tend to induce synergy, and 4) which physiological mechanisms might be responsible for this synergy. Synergy is here defined as mixtures with minimum two-fold difference between observed and predicted effect concentrations using Concentration Addition (CA) as a reference model and including both lethal and sub-lethal endpoints. The results showed that synergy occurred in 7%, 3% and 26% of the 194, 21 and 136 binary pesticide, metal and antifoulants mixtures included in the data compilation on frequency. The difference between observed and predicted effect concentrations was rarely more than 10-fold. For pesticides, synergistic mixtures included cholinesterase inhibitors or azole fungicides in 95% of 69 described cases. Both groups of pesticides are known to interfere with metabolic degradation of other xenobiotics. For the four synergistic metal and 47 synergistic antifoulant mixtures the pattern in terms of chemical groups inducing synergy was less clear. Hypotheses in terms of mechanisms governing these interactions are discussed. It was concluded that true synergistic interactions between chemicals are rare and often occur at high concentrations. Addressing the cumulative rather than synergistic effect of co-occurring chemicals, using standard models as CA, is therefore regarded as the most important step in the risk

Electrochemically induced dual reactive barriers for transformation of TCE and mixture of contaminants in groundwater.

Science.gov (United States)

Mao, Xuhui; Yuan, Songhu; Fallahpour, Noushin; Ciblak, Ali; Howard, Joniqua; Padilla, Ingrid; Loch-Caruso, Rita; Alshawabkeh, Akram N

2012-11-06

A novel reactive electrochemical flow system consisting of an iron anode and a porous cathode is proposed for the remediation of mixture of contaminants in groundwater. The system consists of a series of sequentially arranged electrodes, a perforated iron anode, a porous copper cathode followed by a mesh-type mixed metal oxide anode. The iron anode generates ferrous species and a chemically reducing environment, the porous cathode provides a reactive electrochemically reducing barrier, and the inert anode provides protons and oxygen to neutralize the system. The redox conditions of the electrolyte flowing through this system can be regulated by controlling the distribution of the electric current. Column experiments are conducted to evaluate the process and study the variables. The electrochemical reduction on a copper foam cathode produced an electrode-based reductive potential capable of reducing TCE and nitrate. Rational electrodes arrangement, longer residence time of electrolytes and higher surface area of the foam electrode improve the reductive transformation of TCE. More than 82.2% TCE removal efficiency is achieved for the case of low influent concentration (45 mA). The ferrous species produced from the iron anode not only enhance the transformation of TCE on the cathode, but also facilitates transformation of other contaminants including dichromate, selenate and arsenite. Removal efficiencies greater than 80% are achieved for these contaminants in flowing contaminated water. The overall system, comprising the electrode-based and electrolyte-based barriers, can be engineered as a versatile and integrated remedial method for a relatively wide spectrum of contaminants and their mixtures.

Long-term food-exposure of zebrafish to PCB mixtures mimicking some environmental situations induces ovary pathology and impairs reproduction ability.

Science.gov (United States)

Daouk, Tarek; Larcher, Thibaut; Roupsard, François; Lyphout, Laura; Rigaud, Cyril; Ledevin, Mireille; Loizeau, Véronique; Cousin, Xavier

2011-10-01

Although the use of polychlorinated biphenyls (PCBs) has been banned for several decades, they are still present in the environment and are occasionally mechanically released from sediment or transferred through the trophic chain. Field analyses have established correlations between exposure to PCBs and alterations in fish physiology including reproductive function. Experimental exposures have been mainly performed using dioxin-like PCBs or other congeners at very high concentrations. However, these studies are often difficult to relate to real-life conditions. In the present study, we performed a life-cycle exposure using zebrafish model and mixtures representative of some environmental situations in terms of doses, composition and containing mainly non dioxin-like congeners. Exposure was performed through diet which is the main contamination route in the field. We demonstrated a bioaccumulation of PCBs in males and females as well as a maternal transfer to the eggs. Survival, growth and organ size were similar for all conditions. Several reproductive traits were altered after exposure to a PCB-contaminated diet, including a reduction in the number of fertilized eggs per spawn as well as an increase of the number of poorly fertilized spawns. This latter observation was found irrespective of the sex of contaminated fish. This is related to modifications of ovary histology revealing a decrease of maturing follicles and an increase of atretic follicles in the ovaries of females exposed to PCBs. These results indicate that exposure to PCBs mixtures mimicking some environmental situations, including mainly non dioxin-like congeners, can lead to a dramatic reduction in the number of offspring produced by a female over a lifetime. This is of great concern for wild species living under natural conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

Mixtures of benzo(a)pyrene, dichlorodiphenyltrichloroethane and tributyltin are more toxic to neotropical fish Rhamdia quelen than isolated exposures.

Science.gov (United States)

Oliveira, Heloísa H P; Liebel, Samuel; Rossi, Stéfani C; Azevedo, Ana C B; Barrera, Ellie A L; Garcia, Juan Ramon Esquivel; Grötzner, Sônia Regina; Neto, Francisco Filipak; Randi, Marco A F; Ribeiro, Ciro A O

2015-12-01

activation of cell defenses after the sub-chronic exposure. TBT increased melanomacrophages counting in the 5-day experiment and the mixtures increased it in the 5 and 15-day experiments. Overall, the majority of the biomarkers pointed to a more toxic effect when these contaminants were combined, leading to unexpected toxicities compared to individual exposure scenarios. These findings are relevant considering environmental exposure conditions, since organisms are often exposed to different combinations of contaminants. Copyright © 2015 Elsevier Inc. All rights reserved.

Influence of Wetting and Mass Transfer Properties of Organic Chemical Mixtures in Vadose Zone Materials on Groundwater Contamination by Nonaqueous Phase Liquids

Energy Technology Data Exchange (ETDEWEB)

Charles J Werth; Albert J Valocchi, Hongkyu Yoon

2011-05-21

Previous studies have found that organic acids, organic bases, and detergent-like chemicals change surface wettability. The wastewater and NAPL mixtures discharged at the Hanford site contain such chemicals, and their proportions likely change over time due to reaction-facilitated aging. The specific objectives of this work were to (1) determine the effect of organic chemical mixtures on surface wettability, (2) determine the effect of organic chemical mixtures on CCl4 volatilization rates from NAPL, and (3) accurately determine the migration, entrapment, and volatilization of organic chemical mixtures. Five tasks were proposed to achieve the project objectives. These are to (1) prepare representative batches of fresh and aged NAPL-wastewater mixtures, (2) to measure interfacial tension, contact angle, and capillary pressure-saturation profiles for the same mixtures, (3) to measure interphase mass transfer rates for the same mixtures using micromodels, (4) to measure multiphase flow and interphase mass transfer in large flow cell experiments, all using the same mixtures, and (5) to modify the multiphase flow simulator STOMP in order to account for updated P-S and interphase mass transfer relationships, and to simulate the impact of CCl4 in the vadose zone on groundwater contamination. Results and findings from these tasks and summarized in the attached final report.

Secondary environmental impacts of remedial alternatives for sediment contaminated with hydrophobic organic contaminants.

Science.gov (United States)

Choi, Yongju; Thompson, Jay M; Lin, Diana; Cho, Yeo-Myoung; Ismail, Niveen S; Hsieh, Ching-Hong; Luthy, Richard G

2016-03-05

This study evaluates secondary environmental impacts of various remedial alternatives for sediment contaminated with hydrophobic organic contaminants using life cycle assessment (LCA). Three alternatives including two conventional methods, dredge-and-fill and capping, and an innovative sediment treatment technique, in-situ activated carbon (AC) amendment, are compared for secondary environmental impacts by a case study for a site at Hunters Point Shipyard, San Francisco, CA. The LCA results show that capping generates substantially smaller impacts than dredge-and-fill and in-situ amendment using coal-based virgin AC. The secondary impacts from in-situ AC amendment can be reduced effectively by using recycled or wood-based virgin AC as production of these materials causes much smaller impacts than coal-based virgin AC. The secondary environmental impacts are highly sensitive to the dredged amount and the distance to a disposal site for dredging, the capping thickness and the distance to the cap materials for capping, and the AC dose for in-situ AC amendment. Based on the analysis, this study identifies strategies to minimize secondary impacts caused by different remediation activities: optimize the dredged amount, the capping thickness, or the AC dose by extensive site assessments, obtain source materials from local sites, and use recycled or bio-based AC. Copyright © 2015 Elsevier B.V. All rights reserved.

Shuttle on-orbit contamination and environmental effects

Science.gov (United States)

Leger, L. J.; Jacobs, S.; Ehlers, H. K. F.; Miller, E.

1985-01-01

Ensuring the compatibility of the space shuttle system with payloads and payload measurements is discussed. An extensive set of quantitative requirements and goals was developed and implemented by the space shuttle program management. The performance of the Shuttle system as measured by these requirements and goals was assessed partly through the use of the induced environment contamination monitor on Shuttle flights 2, 3, and 4. Contamination levels are low and generally within the requirements and goals established. Additional data from near-term payloads and already planned contamination measurements will complete the environment definition and allow for the development of contamination avoidance procedures as necessary for any payload.

Method of and apparatus for cleaning garments and soft goods contaminated with nuclear, chemical and/or biological contaminants

International Nuclear Information System (INIS)

Fowler, D.E.

1989-01-01

A method is described for decontaminating garments, soft good or mixtures thereof contaminated with radioactive particulates, toxin, chemical, and biological contaminants comprising the steps of: (a) depositing contaminated garments, soft goods or mixtures thereof in a cleaning drum; (b) charging the drum with a cleaning solvent in which the chemical contaminants are soluble; (c) agitating the drum during a wash cycle to separate radioactive, toxin, biological particulate matter of mixtures thereof from the garments; (d) draining the drum of the dry cleaning solvent which contains suspended particulate contaminants and dissolved chemical contaminants; (e) contacting the drained solvent with both a neutralizing agent and an oxidizing agent, the neutralizing agent being selected from the group consisting of sodium hydroxide, potassium hydroxide and mixtures thereof and having a concentration greater than one (1.0) normal; (f) rinsing the garments, soft goods or mixtures thereof by circulating clean solvent from a solvent tank through the drum thereby effecting additional removal and flushing of particulate and chemical contaminants; (g) filtering the circulated solvent to remove the particulate material suspended in the solvent prior to addition to the drum; and (h) preferentially adsorbing the chemical contaminants dissolved in the circulated solvent prior to addition to the drum

Assessing clustering strategies for Gaussian mixture filtering a subsurface contaminant model

KAUST Repository

Liu, Bo

2016-02-03

An ensemble-based Gaussian mixture (GM) filtering framework is studied in this paper in term of its dependence on the choice of the clustering method to construct the GM. In this approach, a number of particles sampled from the posterior distribution are first integrated forward with the dynamical model for forecasting. A GM representation of the forecast distribution is then constructed from the forecast particles. Once an observation becomes available, the forecast GM is updated according to Bayes’ rule. This leads to (i) a Kalman filter-like update of the particles, and (ii) a Particle filter-like update of their weights, generalizing the ensemble Kalman filter update to non-Gaussian distributions. We focus on investigating the impact of the clustering strategy on the behavior of the filter. Three different clustering methods for constructing the prior GM are considered: (i) a standard kernel density estimation, (ii) clustering with a specified mixture component size, and (iii) adaptive clustering (with a variable GM size). Numerical experiments are performed using a two-dimensional reactive contaminant transport model in which the contaminant concentration and the heterogenous hydraulic conductivity fields are estimated within a confined aquifer using solute concentration data. The experimental results suggest that the performance of the GM filter is sensitive to the choice of the GM model. In particular, increasing the size of the GM does not necessarily result in improved performances. In this respect, the best results are obtained with the proposed adaptive clustering scheme.

Human hepatoma cells exposed to estuarine sediment contaminant extracts permitted the differentiation between cytotoxic and pro-mutagenic fractions

International Nuclear Information System (INIS)

Pinto, M.; Costa, P.M.; Louro, H.; Costa, M.H.; Lavinha, J.

2014-01-01

Complex toxicant mixtures present in estuarine sediments often render contaminant screening unfeasible and compromise determining causation. HepG2 cells were subjected to bioassays with sediment extracts obtained with a series of progressively polar solvents plus a crude extract. The sediments were collected from an impacted area of an estuary otherwise regarded as pristine, whose stressors result mostly from aquaculture effluents and hydrodynamic shifts that enhance particle deposition. Compared to a reference scenario, the most polar extracts yielded highest cytotoxicity while higher genotoxicity (including oxidative damage) was elicited by non-polar solvents. While the former caused effects similar to those expected from biocides, the latter triggered effects compatible with known pro-mutagens like PAHs, even though the overall levels of toxicants were considered of low risk. The results indicate that the approach may constitute an effective line-of-evidence to infer on the predominant set of hazardous contaminants present in complex environmental mixtures. -- Highlights: • Estuarine sediment contaminants were extracted with different organic solvents. • More polar solvents contained the most cytotoxic contaminant fraction. • Non-polar solvents extracted the main genotoxic component of the mixture. • DNA base oxidation was detected through FPG/Comet assay. • The contamination pattern could be inferred from cytoassays with HepG2 cells. -- Polar/non-polar sediment fractions elicited differential cytotoxic and genotoxic effects in human HepG2 cells

Bioremediation of contaminated mixtures of desert mining soil and sawdust with fuel oil by aerated in-vessel composting in the Atacama Region (Chile)

International Nuclear Information System (INIS)

Godoy-Faundez, Alex; Antizar-Ladislao, Blanca; Reyes-Bozo, Lorenzo; Camano, Andres; Saez-Navarrete, Cesar

2008-01-01

Since early 1900s, with the beginning of mining operations and especially in the last decade, small, although repetitive spills of fuel oil had occurred frequently in the Chilean mining desert industry during reparation and maintenance of machinery, as well as casual accidents. Normally, soils and sawdust had been used as cheap readily available sorbent materials of spills of fuel oil, consisting of complex mixtures of aliphatic and aromatic hydrocarbons. Chilean legislation considers these fuel oil contaminated mixtures of soil and sawdust as hazardous wastes, and thus they must be contained. It remains unknown whether it would be feasible to clean-up Chilean desert soils with high salinity and metal content, historically polluted with different commercial fuel oil, and contained during years. Thus, this study evaluated the feasibility of aerated in-vessel composting at a laboratory scale as a bioremediation technology to clean-up contaminated desert mining soils (fuel concentration > 50,000 mg kg -1 ) and sawdust (fuel concentration > 225,000 mg kg -1 ) in the Atacama Region. The composting reactors were operated using five soil to sawdust ratios (S:SD, 1:0, 3:1, 1:1, 1:3, 0:1, on a dry weight basis) under mesophilic temperatures (30-40 deg. C), constant moisture content (MC, 50%) and continuous aeration (16 l min -1 ) during 56 days. Fuel oil concentration and physico-chemical changes in the composting reactors were monitored following standard procedures. The highest (59%) and the lowest (35%) contaminant removals were observed in the contaminated sawdust and contaminated soil reactors after 56 days of treatment, respectively. The S:SD ratio, time of treatment and interaction between both factors had a significant effect (p < 0.050) on the contaminant removal. The results of this research indicate that bioremediation of an aged contaminated mixture of desert mining soil and sawdust with fuel oil is feasible. This study recommends a S:SD ratio 1:3 and a correct

Detection of gases and gas mixtures by correlation spectroscopy

OpenAIRE

Dakin, J.P.; Gunning, M.J.; Chambers, P.

2002-01-01

The reliable detection and monitoring of gases and gas mixtures is known to play a crucial role in many real-world environmental and industrial applications. It is of considerable importance to utilise techniques that are not susceptible to poisoning, are specific to a target gas in a mixture, are unaffected by contaminants, and can be adapted for in-process monitoring. Ever-more stringent requirements in this field dictate a need for ongoing research in this area. As many common gases exhibi...

Phytoremediation of lowland soil contaminated with a formulated mixture of Imazethapyr and Imazapic1

Directory of Open Access Journals (Sweden)

Kelen Müller Souto

Full Text Available The use of plants to decontaminate water and soil contaminated with both organic and inorganic pollutants is a promising technology for sustainable agriculture. The aim of this work was to evaluate the efficiency of plant species in the remediation of formulated mixtures of imazethapyr and imazapic, using the irrigated rice cultivar IRGA 417 as bioindicator. The treatments consisted of the combination of 13 plant species with seven rates of a formulated mixture of imazethapyr and Imazapic (75+25 g e.a. L-1 respectively: 0, 200, 300, 400, 500, 1000 and 4000 mL ha-1. To evaluate the potential for phytoremediation in these species, symptoms of injury and plant height were measured in rice plants at 7, 14, 21 and 28 days after emergence and shoot dry weight at 28 days after emergence. Glycine max, Lolium multiflorum and Lotus corniculatus are potentially promising species in the phytoremediation of soils contaminated with the herbicide imazethapyr and imazapic (up to 4000 mL ha-1, due to being more adapted to hydromorphic environments, which is a feature found in soils cultivated with irrigated rice. Crotalaria juncea, Canavalia ensiformis, Stizolobium aterrimum, Vicia sativa, Raphanus sativus and Triticum aestivum are species capable of the phytoremediation of soils contaminated with imazethapyr + imazapic, however the occurrence of anoxia in hydromorphic soils reduce the establishment and development of these plants.

Environmental contamination in Antarctic ecosystems.

Science.gov (United States)

Bargagli, R

2008-08-01

Although the remote continent of Antarctica is perceived as the symbol of the last great wilderness, the human presence in the Southern Ocean and the continent began in the early 1900s for hunting, fishing and exploration, and many invasive plant and animal species have been deliberately introduced in several sub-Antarctic islands. Over the last 50 years, the development of research and tourism have locally affected terrestrial and marine coastal ecosystems through fuel combustion (for transportation and energy production), accidental oil spills, waste incineration and sewage. Although natural "barriers" such as oceanic and atmospheric circulation protect Antarctica from lower latitude water and air masses, available data on concentrations of metals, pesticides and other persistent pollutants in air, snow, mosses, lichens and marine organisms show that most persistent contaminants in the Antarctic environment are transported from other continents in the Southern Hemisphere. At present, levels of most contaminants in Antarctic organisms are lower than those in related species from other remote regions, except for the natural accumulation of Cd and Hg in several marine organisms and especially in albatrosses and petrels. The concentrations of organic pollutants in the eggs of an opportunistic top predator such as the south polar skua are close to those that may cause adverse health effects. Population growth and industrial development in several countries of the Southern Hemisphere are changing the global pattern of persistent anthropogenic contaminants and new classes of chemicals have already been detected in the Antarctic environment. Although the Protocol on Environmental Protection to the Antarctic Treaty provides strict guidelines for the protection of the Antarctic environment and establishes obligations for all human activity in the continent and the Southern Ocean, global warming, population growth and industrial development in countries of the Southern

Decision support methods for the environmental assessment of contamination at mining sites.

Science.gov (United States)

Jordan, Gyozo; Abdaal, Ahmed

2013-09-01

Polluting mine accidents and widespread environmental contamination associated with historic mining in Europe and elsewhere has triggered the improvement of related environmental legislation and of the environmental assessment and management methods for the mining industry. Mining has some unique features such as natural background pollution associated with natural mineral deposits, industrial activities and contamination located in the three-dimensional sub-surface space, the problem of long-term remediation after mine closure, problem of secondary contaminated areas around mine sites and abandoned mines in historic regions like Europe. These mining-specific problems require special tools to address the complexity of the environmental problems of mining-related contamination. The objective of this paper is to review and evaluate some of the decision support methods that have been developed and applied to mining contamination. In this paper, only those methods that are both efficient decision support tools and provide a 'holistic' approach to the complex problem as well are considered. These tools are (1) landscape ecology, (2) industrial ecology, (3) landscape geochemistry, (4) geo-environmental models, (5) environmental impact assessment, (6) environmental risk assessment, (7) material flow analysis and (8) life cycle assessment. This unique inter-disciplinary study should enable both the researcher and the practitioner to obtain broad view on the state-of-the-art of decision support methods for the environmental assessment of contamination at mine sites. Documented examples and abundant references are also provided.

Developmental Exposure to an Environmental PCB Mixture ...

Science.gov (United States)

Developmental PCB exposure impairs hearing and induces brainstem audiogenic seizures in adult offspring. The degree to which this enhanced susceptibility to seizure is manifest in other brain regions has not been examined. Thus, electrical kindling of the amygdala was used to evaluate the effect of developmental exposure to an environmentally relevant PCB mixture on seizure susceptibility in the rat. Female Long-Evans rats were dosed orally with 0 or 6 mg/kg/day of the PCB mixture dissolved in corn oil vehicle during the perinatal period. On postnatal day (PND) 21, pups were weaned, and two males from each litter were randomly selected for the kindling study. As adults, the male rats were implanted bilaterally with electrodes in the basolateral amygdala. For each animal, afterdischarge (AD) thresholds in the amygdala were determined on the first day of testing followed by once daily stimulation at a standard 200 µA stimulus intensity until three stage 5 generalized seizures (GS) ensued. Developmental PCB exposure did not affect the AD threshold or total cumulative AD duration, but PCB exposure did increase the latency to behavioral manifestations of seizure propagation. PCB exposed animals required significantly more stimulations to reach stage 2 seizures compared to control animals, indicating an attenuated focal (amygdala) excitability. A delay in kindling progression from a focally stimulated limbic site stands in contrast to our previous finding of increase

Priority Environmental Chemical Contaminants in Meat

Science.gov (United States)

Brambilla, Gianfranco; Iamiceli, Annalaura; di Domenico, Alessandro

Generally, foods of animal origin play an important role in determining the exposure of human beings to contaminants of both biological and chemical origins (Ropkins & Beck, 2002; Lievaart et al., 2005). A potentially large number of chemicals could be considered, several of them deserving a particular attention due to their occurrence (contaminations levels and frequencies) and intake scenarios reflecting the differences existing in the economical, environmental, social and ecological contexts in which the “from-farm-to-fork” activities related to meat production are carried out (FAO - Food and Agriculture Organization, 2008).

A possibilistic analysis approach for environmental risk assessment of petroleum-contaminated sites

International Nuclear Information System (INIS)

Liu, L.; Huang, G.H.; Fuller, G.A.

1999-01-01

A possibilistic approach for assessing risks associated with petroleum-contaminated sites is provided. The approach is applied to an illustrative case study in order to show its applicability and implementation for decision making in effective site remediation and management. The approach consists of three main parts: (1) the determination of fuzzy steady state contaminant concentrations in a aquifer based on an analytical solute transport model; (2) possibilistic analysis of fuzzy criteria for different risk levels; and (3) environmental risk assessment based on the Euclidian method. Based on results from an illustrative case study, environmental risks at a petroleum-contaminated site can be effectively evaluated using the developed methodology. The risk assessment framework can effectively handle uncertainities presented as fuzzy numbers. The fuzzy nature of water quality and risk level criteria were seen in the related simulation and evaluation models, and the framework is especially useful for situations in which probabilistic information is not available. This use of this approach is new in the area of petroleum waste management under uncertainty, and its results are useful for the related site remediation and management decisions. 36 refs., 1 tab., 4 figs

Selective flotation for the removal of radionuclides from contaminated soil

International Nuclear Information System (INIS)

Miller, J.D.; Yu, Q.; Lu, Y.Q.

1995-01-01

Low-level radioactive contaminated soils (10--500 pci/gm) created by defense-related activities at certain Superfund sites, such as Nevada Test Site (NTS), is a current environmental concern. Many of these contaminated sites may require appropriate cleanup and restoration, which could cost billions of dollars and put tremendous pressure on limited financial resources. Therefore, the development of a selective flotation process to separate such radionuclides from contaminated soils should be considered. In this study, both a pure depleted UO 2 sample and three synthetic UO 2 /soil mixtures were used to evaluate surface chemistry features and to examine the possibility for the flotation of fine UO 2 particles from selected soils. It was intended that this model system would be a reasonable representation of contaminated soils such as those found the Nevada Test Site which are reported to be contaminated by PuO 2 fallout. The effect of reagent schedule, particle size distribution, and surface charge are discussed with respect to the flotation separation of the UO 2 /soil mixtures. It was found that both commercial fatty acids and reagent grade sodium oleate are effective collectors for UO 2 flotation provided the pH is adjusted to the range of pH 8--9. The bench-scale flotation results successfully demonstrated that froth flotation technology can be used to remove UO 2 from such model contaminated soils with appropriate flotation chemistry conditions which depend on the soil characteristics and other pretreatment procedures

Particle contamination in gas-insulated systems: new control methods and optimum SF6/N2 mixtures

International Nuclear Information System (INIS)

Pace, M.O.; Adcock, J.L.; Christophorou, L.G.

1984-01-01

The feasibilities of two new separate techniques to control particle contamination in practical gas-insulated sytems were tested in a small-scale concentric cylinder geometry. In one technique an insulating coating was first formed on the particles in a contaminated system by low-pressure discharges in appropriate gases such as 1-C 3 F 6 and c-C 4 F 8 . When SF 6 was subsequently introduced into the same system at practical pressure as the operating insulation, the considerable harm ordinarily caused by particles was found to be eliminated. The nature of the coating formed also on the electrodes in this process was studied, with the conclusion that the observed benefits were primarily due to coating on particles, not on electrodes. In the second technique the particles, moved randomly by electrical stress, struck and adhered to the surface of a tacky insulating solid material; they were subsequently encapsulated in a melt-resolidify cycle without electrical stress. This trapping technique was also found to eliminate the harmful effects of particles in SF 6 at practical pressure. A technique for producing a trapping material with temperature characteristics appropriate for practical apparatus was devised. The effect of particle contamination on the dielectric strength of SF 6 /N 2 mixtures was studied as a function of total pressure and percentage of each gas. Optimum total pressure (approx. 6 atm) and optimum percentages (60% SF 6 /40% N 2 ) were observed in breakdown tests in particle-contaminated concentric cylinder geometry

Assessing the wider environmental value of remediating land contamination

NARCIS (Netherlands)

Bardos, R.P.; Kearney, T.E.; Nathanail, C.P.; Weenk, A.; Martin, I.D.

2000-01-01

The aim of this paper is to consider qualitative and quantitative approaches for assessing the wider environmental value of remediating land contamination. In terms of the environmental element of sustainable development, a remediation project's overall environmental performance is the sum of the

Bioremediation of contaminated mixtures of desert mining soil and sawdust with fuel oil by aerated in-vessel composting in the Atacama Region (Chile).

Science.gov (United States)

Godoy-Faúndez, Alex; Antizar-Ladislao, Blanca; Reyes-Bozo, Lorenzo; Camaño, Andrés; Sáez-Navarrete, César

2008-03-01

Since early 1900s, with the beginning of mining operations and especially in the last decade, small, although repetitive spills of fuel oil had occurred frequently in the Chilean mining desert industry during reparation and maintenance of machinery, as well as casual accidents. Normally, soils and sawdust had been used as cheap readily available sorbent materials of spills of fuel oil, consisting of complex mixtures of aliphatic and aromatic hydrocarbons. Chilean legislation considers these fuel oil contaminated mixtures of soil and sawdust as hazardous wastes, and thus they must be contained. It remains unknown whether it would be feasible to clean-up Chilean desert soils with high salinity and metal content, historically polluted with different commercial fuel oil, and contained during years. Thus, this study evaluated the feasibility of aerated in-vessel composting at a laboratory scale as a bioremediation technology to clean-up contaminated desert mining soils (fuel concentration>50,000 mg kg(-1)) and sawdust (fuel concentration>225,000 mg kg(-1)) in the Atacama Region. The composting reactors were operated using five soil to sawdust ratios (S:SD, 1:0, 3:1, 1:1, 1:3, 0:1, on a dry weight basis) under mesophilic temperatures (30-40 degrees C), constant moisture content (MC, 50%) and continuous aeration (16 l min(-1)) during 56 days. Fuel oil concentration and physico-chemical changes in the composting reactors were monitored following standard procedures. The highest (59%) and the lowest (35%) contaminant removals were observed in the contaminated sawdust and contaminated soil reactors after 56 days of treatment, respectively. The S:SD ratio, time of treatment and interaction between both factors had a significant effect (pcontaminant removal. The results of this research indicate that bioremediation of an aged contaminated mixture of desert mining soil and sawdust with fuel oil is feasible. This study recommends a S:SD ratio 1:3 and a correct nutrient balance

Balancing the risks of habitat alteration and environmental contamination in a contaminated forested wetland

International Nuclear Information System (INIS)

Bleiler, J.A.; Daukas, G.; Richardson, N.

1994-01-01

The North Lawrence Oil Dump Site (NLODS) is an inactive hazardous waste site located adjacent to an extensive palustrine forested wetland in upstate New York. Waste oil and oil sludge were disposed of in a lagoon adjacent to the wetland during the 1960s. During periods of high water, oils escaped from the lagoon and were transported into the wetlands. High concentrations of lead and PCBs were detected in NLODS wetland sediments, and contaminants from the site were present in wetland's plant and animal tissues. However, contaminated portions of the wetlands appear to be physically undisturbed and provide high quality wildlife habitat. The results of an ecological risk assessment indicated that lead and PCB contamination in NLODS sediment may be impacting some components of the wetlands community. The risk management process considered both the toxicological risks associated with lead and PCB contamination, as well as the significant habitat destruction risks associated with remediation. Six potential PCB target cleanup levels were evaluated. Following removal of sediments with PCB contamination greater than 0.5 mg/kg, 3.5 acres of sediment with lead contamination in excess of 250 mg/kg (the New York State ''Severe Effect Level'') would remain. More than 1.5 of these acres would contain lead concentrations in excess of 1,000 mg/kg. Reducing lead levels to background concentrations would require more than 50 acres of wetlands alteration. The Record of Decision at the NLODS recognized the high quality habitat provided by the site's wetlands, and attempted to balance the risks from habitat alteration with the risks of environmental contamination

Component effects in mixture experiments

International Nuclear Information System (INIS)

Piepel, G.F.

1980-01-01

In a mixture experiment, the response to a mixture of q components is a function of the proportions x 1 , x 2 , ..., x/sub q/ of components in the mixture. Experimental regions for mixture experiments are often defined by constraints on the proportions of the components forming the mixture. The usual (orthogonal direction) definition of a factor effect does not apply because of the dependence imposed by the mixture restriction, /sup q/Σ/sub i=1/ x/sub i/ = 1. A direction within the experimental region in which to compute a mixture component effect is presented and compared to previously suggested directions. This new direction has none of the inadequacies or errors of previous suggestions while having a more meaningful interpretation. The distinction between partial and total effects is made. The uses of partial and total effects (computed using the new direction) in modification and interpretation of mixture response prediction equations are considered. The suggestions of the paper are illustrated in an example from a glass development study in a waste vitrification program. 5 figures, 3 tables

INFLUENCE OF PETROCHEMICAL INDUSTRY ENVIRONMENTAL CONTAMINANTS ON ANIMAL OVARIAN CELLS

Directory of Open Access Journals (Sweden)

Alexander V. Sirotkin

2012-10-01

Full Text Available The aim of our studies was to examine (1 the effect of environmental contaminants (benzene, toluene and xylen on basic ovarian cell functions (proliferation, apoptosis, secretory activity in different animal species (rabbit, pig, cow, and (2 whether gonadotropic hormone (FSH and plant molecules (quercetin, resveratrol or extract of yucca can affect these functions and modify effect of environmental contaminants. It was observed, that the culture of either porcine or bovine ovarian cells with benzene, toluene or xylen promote apoptosis (accumulation of apoptosis markers bax and p53 and proliferation (accumulation of PCNA. Furthermore, additions of these contaminants were able either up- or down-regulate the release of progesterone, oxytocin, insulin-like growth factor I (IGF-I and prostaglandin F by cultured porcine, rabbit and bovine ovarian cells and their response to addition of FSH. FSH additions promoted proliferation, apoptosis and release of molecules listed above by porcine granulosa cells. Moreover, FSH was able to modify and to prevent. Some effects of BTEX on these cells. The effects of either quercetin or resveratrol on basic porcine ovarian cell functions were observed, but these plant molecules were not able to prevent BTEX effect. Feeding of rabbits with yucca extract caused changes in release of progesterone, IGF-I and prostaglandin F by their ovarian cells, as well as to modify and prevent the influence of benzene on ovarian hormone release. The obtained data suggest that (1 the negative effect of BTEX on reproduction can be due to their influence on ovarian cell apoptosis, proliferation, turnover and release of peptide and steroid hormones and growth factors, and that (2 FSH and plant molecules can regulate ovarian cell functions and prevent some effects of BTEX on these cells.

Cumulative health risk assessment: integrated approaches for multiple contaminants, exposures, and effects

International Nuclear Information System (INIS)

Rice, Glenn; Teuschler, Linda; MacDonel, Margaret; Butler, Jim; Finster, Molly; Hertzberg, Rick; Harou, Lynne

2007-01-01

Available in abstract form only. Full text of publication follows: As information about environmental contamination has increased in recent years, so has public interest in the combined effects of multiple contaminants. This interest has been highlighted by recent tragedies such as the World Trade Center disaster and hurricane Katrina. In fact, assessing multiple contaminants, exposures, and effects has long been an issue for contaminated sites, including U.S. Department of Energy (DOE) legacy waste sites. Local citizens have explicitly asked the federal government to account for cumulative risks, with contaminants moving offsite via groundwater flow, surface runoff, and air dispersal being a common emphasis. Multiple exposures range from ingestion and inhalation to dermal absorption and external gamma irradiation. Three types of concerns can lead to cumulative assessments: (1) specific sources or releases - e.g., industrial facilities or accidental discharges; (2) contaminant levels - in environmental media or human tissues; and (3) elevated rates of disease - e.g., asthma or cancer. The specific initiator frames the assessment strategy, including a determination of appropriate models to be used. Approaches are being developed to better integrate a variety of data, extending from environmental to internal co-location of contaminants and combined effects, to support more practical assessments of cumulative health risks. (authors)

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

Science.gov (United States)

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

2018-04-01

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

Association between environmental contaminants and health outcomes in indigenous populations of the Circumpolar North.

Science.gov (United States)

Singh, Kavita; Bjerregaard, Peter; Chan, Hing Man

2014-01-01

Since the 1990s, research has been carried out to monitor environmental contaminants and their effects on human health in the Arctic. Although evidence shows that Arctic indigenous peoples are exposed to higher levels of contaminants and do worse on several dimensions of health compared with other populations, the contribution of such exposures on adverse outcomes is unclear. The purpose of this review is to provide a synopsis of the published epidemiological literature that has examined association between environmental contaminants and health outcomes in Arctic indigenous populations. A literature search was conducted in OVID Medline (1946-January 2014) using search terms that combined concepts of contaminant and indigenous populations in the Arctic. No language or date restrictions were applied. The reference lists of review articles were hand-searched. Of 559 citations, 60 studies were relevant. The studies fell under the following categories: paediatric (n=18), reproductive health (n=18), obstetrics and gynaecology (n=9), cardiology (n=7), bone health (n=2), oncology (n=2), endocrinology (n=2) and other (n=2). All studies, except one from Arctic Finland, were either from Nunavik or Greenland. Most studies assessed polychlorinated biphenyls (n=43) and organochlorine pesticides (n=29). Fewer studies examined heavy metals, perfluorinated compounds, or polybrominated diphenyl ethers. Details of study results for each health category are provided. It is difficult to make conclusive statements about the effects of environmental contaminants on health due to mixed results, small number of studies and studies being restricted to a small number of regions. Meta-analytical synthesis of the evidence should be considered for priority contaminants and health outcomes. The following research gaps should be addressed in future studies: association of contaminants and health in other Arctic regions (i.e. Inuvialuit Settlement Region, Nunavut, Nunatsiavut, Alaska, European

Prospective mixture risk assessment and management prioritizations for river catchments with diverse land uses

Science.gov (United States)

Brown, Colin D.; de Zwart, Dick; Diamond, Jerome; Dyer, Scott D.; Holmes, Christopher M.; Marshall, Stuart; Burton, G. Allen

2018-01-01

Abstract Ecological risk assessment increasingly focuses on risks from chemical mixtures and multiple stressors because ecosystems are commonly exposed to a plethora of contaminants and nonchemical stressors. To simplify the task of assessing potential mixture effects, we explored 3 land use–related chemical emission scenarios. We applied a tiered methodology to judge the implications of the emissions of chemicals from agricultural practices, domestic discharges, and urban runoff in a quantitative model. The results showed land use–dependent mixture exposures, clearly discriminating downstream effects of land uses, with unique chemical “signatures” regarding composition, concentration, and temporal patterns. Associated risks were characterized in relation to the land‐use scenarios. Comparisons to measured environmental concentrations and predicted impacts showed relatively good similarity. The results suggest that the land uses imply exceedances of regulatory protective environmental quality standards, varying over time in relation to rain events and associated flow and dilution variation. Higher‐tier analyses using ecotoxicological effect criteria confirmed that species assemblages may be affected by exposures exceeding no‐effect levels and that mixture exposure could be associated with predicted species loss under certain situations. The model outcomes can inform various types of prioritization to support risk management, including a ranking across land uses as a whole, a ranking on characteristics of exposure times and frequencies, and various rankings of the relative role of individual chemicals. Though all results are based on in silico assessments, the prospective land use–based approach applied in the present study yields useful insights for simplifying and assessing potential ecological risks of chemical mixtures and can therefore be useful for catchment‐management decisions. Environ Toxicol Chem 2018;37:715–728. © 2017 The Authors

Environmental contamination and its impact on human health

International Nuclear Information System (INIS)

Cornescu, A.

2009-01-01

Chernobyl, site of the worst accident in the history of peaceful use of atomic energy, remain, a huge danger for Europe in the overall levels of exposure to ionizing radiation continues to increase, which is demonstrated by recording new information on biological effects of exposure to radiation (Regional and global aspects of Radiation Protection, IRPA 2007). Criteria fundamental radiation, which is necessary today as result of various practical applications of nuclear energy, obliges us to carefully analyze environmental issue as a result of the presence of radioactive isotopes into the environment. This is due to the fact that the study of correlated environmental contamination and transmission vectors of radionuclides to humans is a primary means to protect public health. (authors)

Environmental dredging residual generation and management.

Science.gov (United States)

Patmont, Clay; LaRosa, Paul; Narayanan, Raghav; Forrest, Casey

2018-05-01

The presence and magnitude of sediment contamination remaining in a completed dredge area can often dictate the success of an environmental dredging project. The need to better understand and manage this remaining contamination, referred to as "postdredging residuals," has increasingly been recognized by practitioners and investigators. Based on recent dredging projects with robust characterization programs, it is now understood that the residual contamination layer in the postdredging sediment comprises a mixture of contaminated sediments that originate from throughout the dredge cut. This mixture of contaminated sediments initially exhibits fluid mud properties that can contribute to sediment transport and contamination risk outside of the dredge area. This article reviews robust dredging residual evaluations recently performed in the United States and Canada, including the Hudson River, Lower Fox River, Ashtabula River, and Esquimalt Harbour, along with other projects. These data better inform the understanding of residuals generation, leading to improved models of dredging residual formation to inform remedy evaluation, selection, design, and implementation. Data from these projects confirm that the magnitude of dredging residuals is largely determined by site conditions, primarily in situ sediment fluidity or liquidity as measured by dry bulk density. While the generation of dredging residuals cannot be avoided, residuals can be successfully and efficiently managed through careful development and implementation of site-specific management plans. Integr Environ Assess Manag 2018;14:335-343. © 2018 The Authors. Integrated Environmental Assessment and Management Published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC). © 2018 The Authors. Integrated Environmental Assessment and Management Published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Environmental contaminants in food. Volume II-part a: working papers. I. Priority setting of toxic substances for guiding monitoring programs. II. Five case studies of environmental food contamination

International Nuclear Information System (INIS)

1980-01-01

This volume contains working papers written for Office of Technology Assessment (OTA) to assist in preparation of the report Environmental Contaminants in Food. The contents include: (1) Priority setting of toxic substances for guiding monitoring programs; and (2) Five case studies of environmental food contamination

Recycling of paint-contaminated grit.

Science.gov (United States)

Taha, R; al-Alawi, D; al-Nabhani, M; Pillay, A E; al-Hamdi, A

2001-08-01

The impact on the environment of using paint-contaminated grit (PCG) as a partial or full replacement for sand in Portland cement mortar and asphalt concrete mixtures was investigated. The grit waste material originated from abrasive blasting of offshore steel structures. There is a major environmental concern regarding the safe disposal of the spent blasting abrasives that contain paint chips or paint particles and other debris removed from the surface of the steel structures. This work investigated the potential reuse of PCG in Portland cement concrete (PCC) and hot mix asphalt concrete. Several studies were conducted to establish the integrity of the materials containing the recycled grit. These included the chemical and physical characterization of natural sand and PCG, the assay of leaches associated with the grit material for hazardous metal contaminants, such as Cr, Cd and Pb, and the assessment of the mechanical properties of the PCG-substituted mortars by applying special tests (such as Marshall stability and determination of the flow properties) to the PCG-substituted asphalt concrete mixtures. The overall results demonstrated that the potential reuse of PCG in PCC and asphalt concrete mixtures would not pose any environmental threat and could produce several benefits, such as reduced disposal costs, protection of water sources from improper disposal practices and reduced costs in the production of natural aggregates and asphalt cement.

Space Environmental Effects Knowledgebase

Science.gov (United States)

Wood, B. E.

2007-01-01

This report describes the results of an NRA funded program entitled Space Environmental Effects Knowledgebase that received funding through a NASA NRA (NRA8-31) and was monitored by personnel in the NASA Space Environmental Effects (SEE) Program. The NASA Project number was 02029. The Satellite Contamination and Materials Outgassing Knowledgebase (SCMOK) was created as a part of the earlier NRA8-20. One of the previous tasks and part of the previously developed Knowledgebase was to accumulate data from facilities using QCMs to measure the outgassing data for satellite materials. The main object of this current program was to increase the number of material outgassing datasets from 250 up to approximately 500. As a part of this effort, a round-robin series of materials outgassing measurements program was also executed that allowed comparison of the results for the same materials tested in 10 different test facilities. Other programs tasks included obtaining datasets or information packages for 1) optical effects of contaminants on optical surfaces, thermal radiators, and sensor systems and 2) space environmental effects data and incorporating these data into the already existing NASA/SEE Knowledgebase.

Microarray applications to understand the impact of exposure to environmental contaminants in wild dolphins (Tursiops truncatus).

Science.gov (United States)

Mancia, Annalaura; Abelli, Luigi; Kucklick, John R; Rowles, Teresa K; Wells, Randall S; Balmer, Brian C; Hohn, Aleta A; Baatz, John E; Ryan, James C

2015-02-01

be heavily contaminated by Aroclor 1268, an uncommon polychlorinated (PCB) mixture. The microarray was able to distinguish dolphins by sex, geographic location, and corroborate previously published health irregularities for the Georgia dolphins. Genes involved in xenobiotic metabolism, development/differentiation and oncogenic pathways were found to be differentially expressed in GA dolphins. The report bridges the advancements in dolphin genome sequencing to the first step towards providing a cost-effective means to screen for indicators of chemical toxin exposure as well as disease status in top level predators. Copyright © 2014 Elsevier B.V. All rights reserved.

Perfluorononanoic acid in combination with 14 chemicals exerts low-dose mixture effects in rats

DEFF Research Database (Denmark)

Hadrup, Niels; Pedersen, Mikael; Skov, Kasper

2016-01-01

Humans are simultaneously exposed to several chemicals that act jointly to induce mixture effects. At doses close to or higher than no-observed adverse effect levels, chemicals usually act additively in experimental studies. However, we are lacking knowledge on the importance of exposure to complex...... real-world mixtures at more relevant human exposure levels. We hypothesised that adverse mixture effects occur at doses approaching high-end human exposure levels. A mixture (Mix) of 14 chemicals at a combined dose of 2.5 mg/kg bw/day was tested in combination with perfluorononanoic acid (PFNA...... pituitary-adrenal axis. In conclusion, our data suggest that mixtures of environmental chemicals at doses approaching high-end human exposure levels can cause a hormonal imbalance and disturb steroid hormones and their regulation. These effects may be non-monotonic and were observed at low doses. Whether...

Mixture design and treatment methods for recycling contaminated sediment

International Nuclear Information System (INIS)

Wang, Lei; Kwok, June S.H.; Tsang, Daniel C.W.; Poon, Chi-Sun

2015-01-01

Graphical abstract: - Highlights: • Contaminated sediment can be recycled as fill material for site formation. • Thermal pretreatment of sediment permits non-load-bearing block application. • CO 2 curing enhances strength and reduces carbon footprint. • Inclusion of granular wastes reinforces the solidified sediment matrix. • Sediment blocks are useful resources for construction use. - Abstract: Conventional marine disposal of contaminated sediment presents significant financial and environmental burden. This study aimed to recycle the contaminated sediment by assessing the roles and integration of binder formulation, sediment pretreatment, curing method, and waste inclusion in stabilization/solidification. The results demonstrated that the 28-d compressive strength of sediment blocks produced with coal fly ash and lime partially replacing cement at a binder-to-sediment ratio of 3:7 could be used as fill materials for construction. The X-ray diffraction analysis revealed that hydration products (calcium hydroxide) were difficult to form at high sediment content. Thermal pretreatment of sediment removed 90% of indigenous organic matter, significantly increased the compressive strength, and enabled reuse as non-load-bearing masonry units. Besides, 2-h CO 2 curing accelerated early-stage carbonation inside the porous structure, sequestered 5.6% of CO 2 (by weight) in the sediment blocks, and acquired strength comparable to 7-d curing. Thermogravimetric analysis indicated substantial weight loss corresponding to decomposition of poorly and well crystalline calcium carbonate. Moreover, partial replacement of contaminated sediment by various granular waste materials notably augmented the strength of sediment blocks. The metal leachability of sediment blocks was minimal and acceptable for reuse. These results suggest that contaminated sediment should be viewed as useful resources

Mixture design and treatment methods for recycling contaminated sediment

Energy Technology Data Exchange (ETDEWEB)

Wang, Lei; Kwok, June S.H.; Tsang, Daniel C.W., E-mail: dan.tsang@polyu.edu.hk; Poon, Chi-Sun

2015-02-11

Graphical abstract: - Highlights: • Contaminated sediment can be recycled as fill material for site formation. • Thermal pretreatment of sediment permits non-load-bearing block application. • CO{sub 2} curing enhances strength and reduces carbon footprint. • Inclusion of granular wastes reinforces the solidified sediment matrix. • Sediment blocks are useful resources for construction use. - Abstract: Conventional marine disposal of contaminated sediment presents significant financial and environmental burden. This study aimed to recycle the contaminated sediment by assessing the roles and integration of binder formulation, sediment pretreatment, curing method, and waste inclusion in stabilization/solidification. The results demonstrated that the 28-d compressive strength of sediment blocks produced with coal fly ash and lime partially replacing cement at a binder-to-sediment ratio of 3:7 could be used as fill materials for construction. The X-ray diffraction analysis revealed that hydration products (calcium hydroxide) were difficult to form at high sediment content. Thermal pretreatment of sediment removed 90% of indigenous organic matter, significantly increased the compressive strength, and enabled reuse as non-load-bearing masonry units. Besides, 2-h CO{sub 2} curing accelerated early-stage carbonation inside the porous structure, sequestered 5.6% of CO{sub 2} (by weight) in the sediment blocks, and acquired strength comparable to 7-d curing. Thermogravimetric analysis indicated substantial weight loss corresponding to decomposition of poorly and well crystalline calcium carbonate. Moreover, partial replacement of contaminated sediment by various granular waste materials notably augmented the strength of sediment blocks. The metal leachability of sediment blocks was minimal and acceptable for reuse. These results suggest that contaminated sediment should be viewed as useful resources.

Micellar Enhanced Ultrafiltration for the Removal of Polycyclic Aromatic Hydrocarbons (PAHs Mixtures in Underground Contaminated Water in Oman

Directory of Open Access Journals (Sweden)

Mohamed Aoudia

2011-12-01

Full Text Available In an attempt to analyze polycyclic aromatic hydrocarbons (PAHs in diesel contaminated underground water in Oman (Rustaq, Gas chromatography-Mass spectrometry was first used to determine the different concentrations in a standard mixture containing 16 PAHs. Retention time and calibration curves were obtained for all aromatic compounds and were used to identify a given analyte as well as its concentration in the contaminated underground water. Micellar enhanced ultrafiltration (MEUF was then used to treat standard aqueous solution of PAHs at low concentration (~ 1 ppb using an edible nonionic surfactant (Tween 80. The totality of the mixture components was completely rejected. Within the experimental detection limit (± 0.01 ppb, the residual PAH concentrations were less than 0.01 ppb in accord with the allowed concentrations in drinking water. Likewise, excellent rejections of PAHs in MEUF treatment of diesel contaminated underground water at an Omani site (Rustaq were observed. The concentration of PAHs was reduced to less than 0.01 ppb, the accepted limit for the most toxic member of the PAH group (benzo(apyrene.

Chemometrics as a tool to analyse complex chemical mixtures

DEFF Research Database (Denmark)

Christensen, J. H.

Chemical characterisation of contaminant mixtures is important for environmental forensics and risk assessment. The great challenge in future research lies in develop- ing suitable, rapid, reliable and objective methods for analysis of the composition of complex chemical mixtures. This thesis...... describes the development of such methods for assessing the identity (chemical fingerprinting) and fate (e.g. biodegradation) of petroleum hydrocarbon mixtures. The methods comply with the general concept that suitable methods must be rapid and inexpensive, objective with limited human in- tervention...... and at the same time must consider a substantial fraction of compounds in the complex mixture. A combination of a) limited sample preparation, b) rapid chemical screening analysis, c) fast and semi-automatic pre-processing, d) compre- hensive multivariate statistical data analysis and e) objective data evaluation...

Dicofol (Kelthane) as an environmental contaminant: A review

Science.gov (United States)

Clark, Donlad R.

1990-01-01

Dicofol is persistent in soil and on plants. No compelling evidence exists that dicofol breaks down or is metabolized to DDTr in nature. Dicofol does not accumulate in birds as rapidly as DDE, and it has reproductive effects that are less harmful than DDE. Fish, birds, and mammals are reproductively sensitive to dicofol products, but levels presently found in wildlife are below levels shown experimentally to cause significant harm. Eggs of fish-eating wild birds from citrus, cotton, and apple-growing areas should be analyzed for dicofol residues. Nest success of fish-eating birds in the most contaminated populations should be studied to evaluate the environmental effects of dicofol.

The extent of environmental and body contamination through aerosols by hydro-surgical debridement in the lumbar spine.

Science.gov (United States)

Putzer, David; Lechner, Ricarda; Coraca-Huber, Debora; Mayr, Astrid; Nogler, Michael; Thaler, Martin

2017-06-01

Surgical site infections occur in 1-6% of spinal surgeries. Effective treatment includes early diagnosis, parenteral antibiotics and early surgical debridement of the wound surface. On a human cadaver, we executed a complete hydro-surgery debridement including a full surgical setup such as draping. The irrigation fluid was artificially contaminated with Staphylococcus aureus (ATCC 6538). Surveillance cultures were used to detect environmental and body contamination of the surgical team. For both test setups, environmental contamination was observed in an area of 6 × 8 m. Both test setups caused contamination of all personnel present during the procedure and of the whole operating theatre. However, the concentration of contamination for the surgical staff and the environment was lower when an additional disposable draping device was used. The study showed that during hydro-surgery debridement, contaminated aerosols spread over the whole surgical room and contaminate the theatre and all personnel.

Bee pollen as a bioindicator of environmental pesticide contamination.

Science.gov (United States)

de Oliveira, Renata Cabrera; Queiroz, Sonia Claudia do Nascimento; da Luz, Cynthia Fernandes Pinto; Porto, Rafael Silveira; Rath, Susanne

2016-11-01

Honeybees and bee products are potential bioindicators of the presence of contaminants in the environment, enabling monitoring of large areas due to the long distances travelled by bees. This work evaluates the use of bee pollen as a bioindicator of environmental contamination by pesticides. A GC-MS/MS analytical method for multiresidue determination of 26 different pesticides in pollen was developed and validated in accordance with the recommendations of the European Union SANCO guide. Environmental monitoring was conducted using the analysis of 145 pollen samples collected from ten beehives in the experimental apiary of Embrapa in Jaguariúna (São Paulo State, Brazil). Bioallethrin and pendimethalin were identified in four and eighteen samples, respectively, at concentrations below the LOQ of the method (25 ng g(-1)). Passive sampling with polyurethane foam discs was used as a control, and no pesticides were found. The detection of pesticide residues in seven samples (33%) from commercial apiaries in Ribeirão Preto (São Paulo State) confirmed the efficiency of the analytical method and the need for environmental monitoring for the presence of pesticide residues. The results demonstrated the potential of bee pollen as a bioindicator of environmental contamination by pesticides. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effect of temperature and a herbicide mixture on freshwater periphytic algae.

Science.gov (United States)

Larras, Floriane; Lambert, Anne-Sophie; Pesce, Stéphane; Rimet, Frédéric; Bouchez, Agnès; Montuelle, Bernard

2013-12-01

Temperature is a strong driver of biofilm formation and of the dynamics of microalgae in freshwater. Moreover, exposure to herbicides is a well-known stressor of periphytic communities in anthropized aquatic environments. We tested these two environmental factors on periphytic communities that had been sampled from the littoral zone of Lake Geneva and acclimatized in the lab for 3 weeks at 18, 21, 24 and 28 °C. After this acclimation period, differences in the composition of the diatom community and decreases in cell density were observed corresponding to the temperature gradient. These acclimated communities were then exposed to 23 and 140 nM of a mixture composed of equitoxic quantities of atrazine, terbutryn, diuron and isoproturon. The periphytic community was more sensitive to the herbicide mixture at 18 °C than at higher temperatures, suggesting that higher temperature reduced its toxicity. Small and pioneer diatom species known to be promoted by contamination also appeared to benefit from higher temperatures. Temperature therefore appears to condition the herbicide sensitivity of periphytic communities. © 2013 Elsevier Inc. All rights reserved.

Bioremediation potential of a tropical soil contaminated with a mixture of crude oil and production water.

Science.gov (United States)

Alvarez, Vanessa Marques; Santos, Silvia Cristina Cunha Dos Santos; Casella, Renata da Costa; Vital, Ronalt Leite; Sebastin, Gina Vasquez; Seldin, Lucy

2008-12-01

A typical tropical soil from the northeast of Brazil, where an important terrestrial oil field is located, was accidentally contaminated with a mixture of oil and saline production water. To study the bioremediation potential in this area, molecular methods based on PCR-DGGE were used to determine the diversity of the bacterial communities in bulk and in contaminated soils. Bacterial fingerprints revealed that the bacterial communities were affected by the presence of the mixture of oil and production water, and different profiles were observed when the contaminated soils were compared with the control. Halotolerant strains capable of degrading crude oil were also isolated from enrichment cultures obtained from the contaminated soil samples. Twenty-two strains showing these features were characterized genetically by amplified ribosomal DNA restriction analysis (ARDRA) and phenotypically by their colonial morphology and tolerance to high NaCl concentrations. Fifteen ARDRA groups were formed. Selected strains were analyzed by 16S rDNA sequencing, and Actinobacteria was identified as the main group found. Strains were also tested for their growth capability in the presence of different oil derivatives (hexane, dodecane, hexadecane, diesel, gasoline, toluene, naphthalene, o-xylene, and p-xylene) and different degradation profiles were observed. PCR products were obtained from 12 of the 15 ARDRA representatives when they were screened for the presence of the alkane hydroxylase gene (alkB). Members of the genera Rhodococcus and Gordonia were identified as predominant in the soil studied. These genera are usually implicated in oil degradation processes and, as such, the potential for bioremediation in this area can be considered as feasible.

Chemistry and preliminary environmental effects of mixtures of triisopropyl phosphite, Bis-(2-ethylexyl)-phosphonate, and sulfur. Final report

Energy Technology Data Exchange (ETDEWEB)

Cataldo, D.A.; Harvey, S.D.; McVeety, B.D.; Fellows, R.J.; Van Noris, P.

1991-12-01

The present studies were performed to evaluate the reaction chemistry and preliminary biotic impacts of BIS, TIP, and TIPS. Reaction chemistry studies were designed to simulate in-flight mixing characteristics. The binary mixture undergoes rapid and nearly complete reaction. The final products released to the environment are TIPS and excess elemental sulfur. There is an apparent species sensitivity difference in algae for the simulants BIS, TIP, and TIPS, with Chlorella being more sensitive than Selenastrum based on cell number studies. However, the extent of adverse effects was not excessive for either algal species. There was no apparent effect of TIP or TIPS on the electron transport systems of isolated chloroplasts at the concentration tested (10 ppm). In general, it is unlikely that environmental release of these products would have significant or lasting effects, based on the preliminary algal tests and electron transport studies.

Lindane contaminated soil bio stimulation with vegetable organic nitrogenated extracts: effects on soil biochemistry

International Nuclear Information System (INIS)

Garcia-Martinez, A. M.; Tejada, M.; Diaz, A. I.; Rodriguez-Morgado, B.; Bautista, J.; Parrado, J.

2009-01-01

1,2,3,4,5,6-Hexachlorocyclohexane (HCH) was one of the most extensively used organo chloride insecticides. Technical mixture of HCH consists of eight steric isomers but only the y-isomer, known as lindane, is insecticides and it is commercial. Despite the fact that most countries have prohibited the production and use of the toxic lindane (Voldner, et al, 1995), many contaminated soils remain because of the long persistence of lindane (MacRae et al, 1948) and, as a result, it cause environmental disease. (Author)

Novel Approach for the Remediation of Radioactive Cesium Contaminated Soil with nano-Fe/Ca/CaO Dispersion Mixture in Dry Condition

Directory of Open Access Journals (Sweden)

Mallampati S. R.

2013-04-01

Full Text Available Present study, first time we developed a nano-Fe/Ca/CaO dispersion mixture based remediation and volume reduction method of real radioactive cesium contaminated soils. After soil samples treated with 10wt% of nano-Fe/Ca/CaO dispersion mixtures, emitting radiation intensity was reduced from 4.00 μSv/h to 0.95 μSv/h in non-magnetic fraction soils. While, after treatment, about 30wt% magnetic and 70wt% nonmagnetic fraction soils were separated, and it’s condensed radioactive cesium concentration was about 80% and 20%, respectively. By this way, cesium contaminated soil volume can be reduced. These preliminary results appear to be very promising and the simple mixing with the addition of nano-Fe/Ca/CaO may be considered potentially applicable for the remediation and separation of radioactive Cs contaminated soil in dry conditions.

Solidification treatment of thiophene and BTEX contaminated soils

International Nuclear Information System (INIS)

Zarlinski, S.J.; Kingham, N.W.; Blevins, J.

1995-01-01

Contamination at the McColl Superfund Site, located in Fullerton, California, is due to the disposal, in pits, of spent sulfuric acid sludge from the production of aviation fuel. A treatability study was performed to evaluate the electiveness of in situ solidification treatment of materials contaminated with high concentrations of benzene, toluene, ethylbenzene, and xylenes (BTEX), as well as thiophene and other organic compounds. The contaminated materials were extremely acidic (pH<1) and had high organic and sulfur contents of greater than 70 percent and 10 percent, respectively. A total of 150 mixtures were screened to evaluate the effectiveness of 15 reagents. Based on the preliminary screening results, six mixtures were selected as being the most effective at treating the contaminated materials. Comprehensive evaluations of the candidate mixtures included (1) quantitative glovebag volatilization studies, (2) chemical characterization of the treated materials, (3) strength characterizations at multiple cure times of up to 60 days, (4) emissions monitoring of the treated materials at cure times of 7 and 14 days, and (5) the evaluation of oxidation reagents for treatment of the thiophene contamination. The treatability study demonstrated that solidification treatment is an effective alternative for remediation of the thiophene and BTEX contaminated materials

Ecotoxicity on a stick: A novel analytical tool for predicting the ecotoxicity of petroleum contaminated samples

International Nuclear Information System (INIS)

Parkerton, T.F.; Stone, M.A.

1995-01-01

Hydrocarbons generally elicit toxicity via a nonpolar narcotic mechanism. Recent research suggests that chemicals acting by this mode invoke ecotoxicity when the molar concentration in organisms lipid exceeds a critical threshold. Since ecotoxicity of nonpolar narcotic mixtures appears to be additive, the ecotoxicity of hydrocarbon mixtures thus depends upon: (1) the partitioning of individual hydrocarbons comprising the mixture from the environment to lipids and (2) the total molar sum of the constituent hydrocarbons in lipids. These insights have led previous investigators to advance the concept of biomimetic extraction as a novel tool for assessing potential narcosis-type or baseline ecotoxicity in aqueous samples. Drawing from this earlier work, the authors have developed a method to quantify Bioavailable Petroleum Hydrocarbons (BPHS) in hydrocarbon-contaminated aqueous and soil/sediment samples. A sample is equilibrated with a solid phase microextraction (SPME) fiber that serves as a surrogate for organism lipids. The total moles of hydrocarbons that partition to the SPME fiber is then quantified using a simple GC/FID procedure. Research conducted to support the development and initial validation of this method will be presented. Results suggest that BPH analyses provide a promising, cost-effective approach for predicting the ecotoxicity of environmental samples contaminated with hydrocarbon mixtures. Consequently, BPH analyses may provide a valuable analytical screening tool for ecotoxicity assessment in product and effluent testing, environmental monitoring and site remediation applications

An emergency decision-making on a regional environmental contamination

International Nuclear Information System (INIS)

Yasuda, Hiroshi

1996-01-01

When an environmental contamination occurs in a wide area, it is necessary to estimate the future influence by emergent environmental monitoring and rapidly take measures for it. This study aimed to support an emergency decision-making by constructing practical schemes with regards to the following three items in the dose limitation system recommended by ICRP; validity of intervention actions, optimization of protection and dose limitation. A framework of decision-making process was constructed to make clear the corresponding responsibility and the principle of intervention, to introduce stochastic techniques for estimating the environmental radiation shift and to reduce the social burden for the contamination. The results obtained by using this method were variable depending on the characteristics of subjects and regions applied. Therefore, it is needed to select an appropriate evaluation model and specific parameters suitable for the respective cases. (M.N.)

Older Adults' Perceptions of Nutrition as Protective against Detrimental Effects of Environmental Pollution

Science.gov (United States)

Dunn, Kristina; Gaetke, Lisa; Stephenson, Tammy; Brewer, Dawn

2017-01-01

The aging process makes older adults vulnerable to the detrimental health effects of environmental contaminants. Our study assessed older adults' perceptions regarding diet as protective against environmental contaminants, levels of concern about exposure to environmental contaminants, and interest in learning about protective food-related…

Carbapenem-Resistant Acinetobacter baumannii: Concomitant Contamination of Air and Environmental Surfaces.

Science.gov (United States)

Shimose, Luis A; Masuda, Eriko; Sfeir, Maroun; Berbel Caban, Ana; Bueno, Maria X; dePascale, Dennise; Spychala, Caressa N; Cleary, Timothy; Namias, Nicholas; Kett, Daniel H; Doi, Yohei; Munoz-Price, L Silvia

2016-07-01

OBJECTIVE To concomitantly determine the differential degrees of air and environmental contamination by Acinetobacter baumannii based on anatomic source of colonization and type of ICU layout (single-occupancy vs open layout). DESIGN Longitudinal prospective surveillance study of air and environmental surfaces in patient rooms. SETTING A 1,500-bed public teaching hospital in Miami, Florida. PATIENTS Consecutive A. baumannii-colonized patients admitted to our ICUs between October 2013 and February 2014. METHODS Air and environmental surfaces of the rooms of A. baumannii-colonized patients were sampled daily for up to 10 days. Pulsed-field gel electrophoresis (PFGE) was used to type and match the matching air, environmental, and clinical A. baumannii isolates. RESULTS A total of 25 A. baumannii-colonized patients were identified during the study period; 17 were colonized in the respiratory tract and 8 were colonized in the rectum. In rooms with rectally colonized patients, 38.3% of air samples were positive for A. baumannii; in rooms of patients with respiratory colonization, 13.1% of air samples were positive (P=.0001). In rooms with rectally colonized patients, 15.5% of environmental samples were positive for A. baumannii; in rooms of patients with respiratory colonization, 9.5% of environmental samples were positive (P=.02). The rates of air contamination in the open-layout and single-occupancy ICUs were 17.9% and 21.8%, respectively (P=.5). Environmental surfaces were positive in 9.5% of instances in open-layout ICUs versus 13.4% in single-occupancy ICUs (P=.09). CONCLUSIONS Air and environmental surface contaminations were significantly greater among rectally colonized patients; however, ICU layout did not influence the rate of contamination. Infect Control Hosp Epidemiol 2016;37:777-781.

Enclosure design for flock-level, chronic exposure of birds to air contaminant mixtures.

Science.gov (United States)

North, Michelle A; Kinniburgh, David W; Smits, Judit E G

2018-05-01

The objective of this study was to design an enclosure suitable for studying the ecotoxicological effects of vehicle emissions on groups of wild birds without compromising welfare. Two, adjacent enclosures sheltered from sunlight, wind and rain, were bird-proofed and wrapped with thick polyethylene sheeting. Emissions were directed into the treatment enclosure from the exhaust of a light-duty gasoline truck, using flexible, heat-proof pipe, with joins sealed to prevent leakage. During active exposure, the engine was idled for 5 h/day, 6 days/week for 4 weeks. Fans maintained positive pressure (controls) and negative pressure (treatment), preventing cross-contamination of enclosures and protecting investigators. Four sets of passive, badge-type samplers were distributed across each enclosure, measuring nitrogen dioxide, sulfur dioxide and volatile organic compounds (NO 2 , SO 2 and VOCs, respectively), and were complemented by active monitors measuring VOCs and particulate matter (2.5 µm diameter, PM 2.5 ). We found that the concentrations of NO 2 , SO 2 and PM 2.5 were not different between treatment and control enclosures. Volatile organic compounds (e.g. benzene, toluene, ethylbenzene and xylenes) were approximately six times higher in the treatment enclosure than control (13.23 and 2.13 µg m -1 , respectively). In conclusion, this represents a successful, practical design for studying the effects of sub-chronic to chronic exposure to realistic mixtures of vehicle exhaust contaminants, in groups of birds. Recommended modifications for future research include a chassis dynamometer (vehicle treadmill), to better replicate driving conditions including acceleration and deceleration.

Contaminant Effects on California Bay–Delta Species and Human Health

Directory of Open Access Journals (Sweden)

Stephanie Fong

2016-12-01

Full Text Available doi: https://doi.org/10.15447/sfews.2016v14iss4art5Many contaminants in the California Bay–Delta (Bay–Delta exceed regulatory standards, affect aquatic species, and potentially affect human health. Recent studies provide multiple lines of evidence that contaminants affect species of concern in the Bay–Delta (e.g., the decline of several important fish species referred to as the “Pelagic Organism Decline” or POD. Contaminants occur as dynamic complex mixtures and exert effects at multiple levels of biological organization. Multiple chemicals impair processes at cellular and physiological levels (measured as growth, development, and behavior abnormalities, and when viability and reproductive output are affected, populations are affected. As an important example, the population decline of the endangered Delta Smelt (Hypomesus transpacificus is significantly associated with multiple stressors, including insecticide use. New analyses presented in this paper show significant correlations between pyrethroid use and declining abundance of POD fish species. Water sampled from the Bay–Delta causes multiple deleterious effects in fish, and Delta Smelt collected from the Bay–Delta exhibit contaminant effects. Fish prey items are also affected by contaminants; this may have an indirect effect on their populations. Co-occurrence with thermal changes or disease can exacerbate contaminant effects. Contaminants also pose threats to human health via consumption of fish and shellfish, drinking water, and contact recreation, in particular, mercury, cyanobacteria toxins, disinfection byproducts, pathogens, pesticides, and pharmaceuticals and personal care products. The role of contaminants in the decline of Bay–Delta species is difficult to accurately assess in a complex, dynamic system. However, tools and approaches are available to evaluate contaminant effects on Bay–Delta species, and separate the effects of multiple stressors. Integrated

A role of low dose chemical mixtures in adipose tissue in carcinogenesis.

Science.gov (United States)

Lee, Duk-Hee; Jacobs, David R; Park, Ho Yong; Carpenter, David O

2017-11-01

The Halifax project recently hypothesized a composite carcinogenic potential of the mixture of low dose chemicals which are commonly encountered environmentally, yet which are not classified as human carcinogens. A long neglected but important fact is that adipose tissue is an important exposure source for chemical mixtures. In fact, findings from human studies based on several persistent organic pollutants in general populations with only background exposure should be interpreted from the viewpoint of chemical mixtures because serum concentrations of these chemicals can be seen as surrogates for chemical mixtures in adipose tissue. Furthermore, in conditions such as obesity with dysfunctional adipocytes or weight loss in which lipolysis is increased, the amount of the chemical mixture released from adipose tissue to circulation is increased. Thus, both obesity and weight loss can enhance the chance of chemical mixtures reaching critical organs, however paradoxical this idea may be when fat mass is the only factor considered. The complicated, interrelated dynamics of adipocytes and chemical mixtures can explain puzzling findings related to body weight among cancer patients, including the obesity paradox. The contamination of fat in human diet with chemical mixtures, occurring for reasons similar to contamination of human adipose tissue, may be a missing factor which affects the association between dietary fat intake and cancer. The presence of chemical mixtures in adipose tissue should be considered in future cancer research, including clinical trials on weight management among cancer survivors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Listeria monocytogenes contamination in dairy plants: evaluation of Listeria monocytogenes environmental contamination in two cheese-making plants using sheeps milk

Directory of Open Access Journals (Sweden)

Michela Ibba

2013-09-01

Full Text Available Listeria monocytogenes harbouring niches established in the processing plant support post-process contamination of dairy products made from pasteurised or thermised milk. The present study investigated L. monocytogenes environmental contamination in two sheep’s milk cheese-making plants. Persistence of contamination in the area at higher risk was also investigated. During a one-year survey 7 samplings were carried out in each dairy plant, along the production lines of Pecorino Romano and ricotta salata cheese. A total of 613 environmental samples collected from food contact and non-food contact surfaces were analysed according to ISO 11290-1:2005 standard method. Identification of the isolated strains was carried out by polymerase chain reaction. L. monocytogenes prevalence was 23.2% in dairy A and 13.1% in dairy B, respectively. The higher prevalence rate was found in the following areas: salting, products washing, packaging, ricotta salata storage and Pecorino Romano ripening rooms. L. monocytogenes was never found in the cheese-making area. The probability of observing samples positive for the presence of L. monocytogenes was asso- ciated with dairy plant, sampling area and the period of cheese-making (P<0.001. The greater persistence of contamination over time was observed in the washing, salting, and Pecorino Romano ripening areas. The control of persistent environmental contamination relies on the identification of L. monocytogenes niches within the processing environment and the prevention of harborage sites formation. The importance of strict cleaning and sanitising procedure in controlling L. monocytogenes environmental contamination is confirmed by the lower level of contamination observed after these procedures were correctly implemented.

Ecotoxicological evaluation of diesel-contaminated soil before and after a bioremediation process.

Science.gov (United States)

Molina-Barahona, L; Vega-Loyo, L; Guerrero, M; Ramírez, S; Romero, I; Vega-Jarquín, C; Albores, A

2005-02-01

Evaluation of contaminated sites is usually performed by chemical analysis of pollutants in soil. This is not enough either to evaluate the environmental risk of contaminated soil nor to evaluate the efficiency of soil cleanup techniques. Information on the bioavailability of complex mixtures of xenobiotics and degradation products cannot be totally provided by chemical analytical data, but results from bioassays can integrate the effects of pollutants in complex mixtures. In the preservation of human health and environment quality, it is important to assess the ecotoxicological effects of contaminated soils to obtain a better evaluation of the healthiness of this system. The monitoring of a diesel-contaminated soil and the evaluation of a bioremediation technique conducted on a microcosm scale were performed by a battery of ecotoxicological tests including phytotoxicity, Daphnia magna, and nematode assays. In this study we biostimulated the native microflora of soil contaminated with diesel by adding nutrients and crop residue (corn straw) as a bulking agent and as a source of microorganisms and nutrients; in addition, moisture was adjusted to enhance diesel removal. The bioremediation process efficiency was evaluated directly by an innovative, simple phytotoxicity test system and the diesel extracts by Daphnia magna and nematode assays. Contaminated soil samples were revealed to have toxic effects on seed germination, seedling growth, and Daphnia survival. After biostimulation, the diesel concentration was reduced by 50.6%, and the soil samples showed a significant reduction in phytotoxicity (9%-15%) and Daphnia assays (3-fold), confirming the effectiveness of the bioremediation process. Results from our microcosm study suggest that in addition to the evaluation of the bioremediation processes efficiency, toxicity testing is different with organisms representative of diverse phylogenic levels. The integration of analytical, toxicological and bioremediation data

Environmental materials for remediation of soils contaminated with lead and cadmium using maize (Zea mays L.) growth as a bioindicator.

Science.gov (United States)

Shi, Yu; Huang, Zhanbin; Liu, Xiujie; Imran, Suheryani; Peng, Licheng; Dai, Rongji; Deng, Yulin

2016-04-01

Heavy metal pollution is a severe environmental problem. Remediation of contaminated soils can be accomplished using environmental materials that are low cost and environmentally friendly. We evaluated the individual and combination effects of humic acid (HA), super absorbent polymer (SAP), zeolite (ZE), and fly ash composites (FC) on immobilization of lead (Pb) and cadmium (Cd) in contaminated soils. We also investigated long-term practical approaches for remediation of heavy metal pollution in soil. The biochemical and morphological properties of maize (Zea mays L.) were selected as biomarkers to assess the effects of environmental materials on heavy metal immobilization. The results showed that addition of test materials to soil effectively reduced heavy metal accumulation in maize foliage, improving chlorophyll levels, plant growth, and antioxidant enzyme activity. The test materials reduced heavy metal injury to maize throughout the growth period. A synergistic effect from combinations of different materials on immobilization of Pb and Cd was determined based on the reduction of morphological and biochemical injuries to maize. The combination of zeolite and humic acid was especially effective. Treatment with a combination of HA + SAP + ZE + FC was superior for remediation of soils contaminated with high levels of Pb and Cd.

Pharmaceuticals and personal care products (PPCPs): a review on environmental contamination in China.

Science.gov (United States)

Liu, Jin-Lin; Wong, Ming-Hung

2013-09-01

Pharmaceuticals and personal care products (PPCPs) which contain diverse organic groups, such as antibiotics, hormones, antimicrobial agents, synthetic musks, etc., have raised significant concerns in recently years for their persistent input and potential threat to ecological environment and human health. China is a large country with high production and consumption of PPCPs for its economic development and population growth in recent years. This may result in PPCP contamination in different environmental media of China. This review summarizes the current contamination status of different environment media, including sewage, surface water, sludge, sediments, soil, and wild animals, in China by PPCPs. The human body burden and adverse effects derived from PPCPs are also evaluated. Based on this review, it has been concluded that more contamination information of aquatic environment and wildlife as well as human body burden of PPCPs in different areas of China is urgent. Studies about their environmental behavior and control technologies need to be conducted, and acute and chronic toxicities of different PPCP groups should be investigated for assessing their potential ecological and health risks. © 2013.

Sources to environmental radioactive contamination from nuclear activities in the former USSR

International Nuclear Information System (INIS)

Polikarpov, G.G.; Aarkrog, A.

1993-01-01

There is three major sites of radioactive environmental contamination in the former USSR: the Cheliabinsk region in the Urals, Chernobyl NPP in Ukraine and Novaya Zemlya in the Arctic Ocean. The first mentioned is the most important with regard to local (potential) contamination, the last one dominates the global contamination. A number of sites and sources are less well known with regard to environmental contamination. This is thus the case for the plutonium production factories at Tomsk and Dodonovo. More information on nuclear reactors in lost or dumped submarines is also needed. From a global point of view reliable assessment of the radioactive run-off from land and deposits of nuclear waste in the Arctic Ocean are in particular pertinent

Effect-directed analysis and mixture effects of AhR-active PAHs in crude oil and coastal sediments contaminated by the Hebei Spirit oil spill

International Nuclear Information System (INIS)

Hong, Seongjin; Lee, Sangwoo; Choi, Kyungho; Kim, Gi Beum; Ha, Sung Yong; Kwon, Bong-Oh; Ryu, Jongseong; Yim, Un Hyuk; Shim, Won Joon; Jung, Jinho; Giesy, John P.; Khim, Jong Seong

2015-01-01

The major AhR-active PAHs were identified in crude oil and oil-contaminated sediments by use of effect-directed analysis. As part of the study, an enhanced potency balance analysis was conducted by establishing the novel relative potency values of (alkyl)-PAHs from the H4IIE-luc bioassay. Silica gel column fractionation of crude oil resulted in greater AhR-mediated potencies in fractions of aromatics (F2) and resins (F3), and such trend was also observed for field collected sediment samples. AhR-mediated potencies of six F2 sub-fractions from HPLC indicated that the majority of F2 responses were attributable to 3–4 ring aromatics. Target PAHs including C4-phenanthrene, C1-chrysene, and C3-chrysene in sediments explained ∼18% of the bioassay-derived TCDD-EQs, however, the unknown AhR agonists and potential mixture effects remain in question. Overall, the AhR-potency and antagonistic potential of residual oil in sediment tended to decrease over time, thus monitoring of weathering process would be key for the post management of oil-contaminated sites. - Highlights: • AhR-active PAHs in crude oil and sediments were newly determined using EDA. • Novel relative potency values of (alkyl)-PAHs for AhR activity were established. • Three to four ring PAHs were identified to be major AhR agonists in crude oil. • Parent and alkyl-PAHs explained ∼18% of the total AhR-mediated potencies of crude oil. • AhR-mediated potencies apparently decreased by the timely weathering processes. - “Major AhR agonists were identified three to four ring PAHs in crude oil and sediments determined by use of effect-directed analysis.”

Development of a decision support system to manage contamination in marine ecosystems.

Science.gov (United States)

Dagnino, A; Viarengo, A

2014-01-01

In recent years, contamination and its interaction with climate-change variables have been recognized as critical stressors in coastal areas, emphasizing the need for a standardized framework encompassing chemical and biological data into risk indices to support decision-making. We therefore developed an innovative, expert decision support system (Exp-DSS) for the management of contamination in marine coastal ecosystems. The Exp-DSS has two main applications: (i) to determine environmental risk and biological vulnerability in contaminated sites; and (ii) to support the management of waters and sediments by assessing the risk due to the exposure of biota to these matrices. The Exp-DSS evaluates chemical data, both as single compounds and as total toxic pressure of the mixture, to compare concentrations to effect-based thresholds (TELs and PELs). Sites are then placed into three categories of contamination: uncontaminated, mildly contaminated, and highly contaminated. In highly contaminated sites, effects on high-level ecotoxicological endpoints (i.e. survival and reproduction) are used to determine risk at the organism-population level, while ecological parameters (i.e. alterations in community structure and ecosystem functions) are considered for assessing effects on biodiversity. Changes in sublethal biomarkers are utilized to assess the stress level of the organisms in mildly contaminated sites. In Triad studies, chemical concentrations, ecotoxicological high-level effects, and ecological data are combined to determine the level of environmental risk in highly contaminated sites; chemical concentration and ecotoxicological sublethal effects are evaluated to determine biological vulnerability in mildly contaminated sites. The Exp-DSS was applied to data from the literature about sediment quality in estuarine areas of Spain, and ranked risks related to exposure to contaminated sediments from high risk (Huelva estuary) to mild risk (Guadalquivir estuary and Bay of

A managed approach to achieve a safe, cost effective, and environmentally sound demolition of a plutonium-238 contaminated building

International Nuclear Information System (INIS)

Jaeger, Ralph R.; Geichman, Jack R.; Keener, Douglas E.; Farmer, Billy M.

1992-01-01

DOE's Mound Plant has the problem of demolishing a former plutonium-238 processing facility, the Special Metallurgical (SM) Building. The building is located within 200 feet of a major public road and golf course. Previous removal efforts on appendages to the building used the technique of tenting small segments and used labor intensive segment-by-segment removal with expendable hand tools. This approach was very slow and costly, but offered good environmental control of radioactive contamination. It was realized that this method, when applied to the entire structure of the building, would not only be very costly, but would also be of high risk to worker safety and worker exposure to contamination. The new approach to overcome these problems is to dismantle the building structure using a rotating grapple to hold sections of the building structure while a portable rotating shear cuts the steel beams into appropriate lengths for loading directly into large waste containers. By the former method, the cut jagged steel would be size reduced with hand tools and loaded into waste containers manually. The additional handling has a high probability of producing minor, yet potentially contaminated, skin lacerations. The shear and grapple method eliminates this hazard. To apply this safer and more cost effective technology, Mound had to assure that the method would be environmentally sound and that neither onsite workers or the general public would be exposed to radioactivity. The Annex was decontaminated to as low as reasonably possible and the contaminated interior painted. However, there were numerous areas where contamination could be trapped. Mound conducted a formal sampling of these areas and had the results modeled for potential release during demolition. The results of this sampling and modeling effort showed that the building could be dismantled using this technology without producing a harmful effect on the environment. Application of this managed approach to the

Osprey: worldwide sentinel species for assessing and monitoring environmental contamination in rivers, lakes, reservoirs, and estuaries.

Science.gov (United States)

Grove, Robert A; Henny, Charles J; Kaiser, James L

2009-01-01

In the United States, many fish and wildlife species have been used nationwide to monitor environmental contaminant exposure and effects, including carcasses of the bald eagle (Haliaeetus leucocephalus), the only top avian predator regularly used in the past. Unfortunately, bald eagles are sensitive to investigator intrusion at the nest. Thus, the osprey (Pandion haliaetus) is evaluated as a potential sentinel species for aquatic ecosystems. Several characteristics support the choice of the osprey as a sentinel species, including: (1) fish-eating diet atop the aquatic food web, (2) long-lived with strong nest fidelity, (3) adapts to human landscapes (potentially the most contaminated), (4) tolerates short-term nest disturbance, (5) nests spatially distributed at regular intervals, (6) highly visible nests easily located for study, (7) ability to accumulate most, if not all, lipophilic contaminants, (8) known sensitivity to many contaminants, and (9) nearly a worldwide distribution. These osprey traits have been instrumental in successfully using the species to understand population distribution, abundance, and changes over time; the effects of various contaminants on reproductive success; how contaminants in prey (fish on biomass basis) contribute to egg concentrations (i.e., biomagnification factors); and spatial residue patterns. Data summarized include nesting population surveys, detailed nesting studies, and chemical analyses of osprey egg, organ, blood, and feather samples for contaminants that bioaccumulate and/or biomagnify in aquatic food webs; and biochemical evaluations of blood and various organs. Studies in the United States, Canada, Mexico, Europe, and elsewhere have shown the osprey to be a useful sentinel species for monitoring selected environmental contaminants, including some emerging contaminants in lakes, reservoirs, rivers, and estuaries.

Impact of benzo(a)pyrene, Cu and their mixture on the proteomic response of Mytilus galloprovincialis

International Nuclear Information System (INIS)

Maria, V.L.; Gomes, T.; Barreira, L.; Bebianno, M.J.

2013-01-01

Highlights: •Distinct protein expression profiles dependent of BaP and Cu accumulation, metabolism and chemical interactions in mussels, Mytilus galloprovincialis. •Processes that involve adhesion and motility, cytoskeleton and cell structure, stress response, transcription regulation and energy metabolism are common mechanisms. •Traditional (ATP synthase, GST, HSP and actin) and novel biomarkers for BaP (ZFP), Cu (chitin synthase) and mixture (MVP) exposures identified in mussels. -- Abstract: In natural waters, chemical interactions between mixtures of contaminants can result in potential synergistic and/or antagonic effects in aquatic animals. Benzo(a)pyrene (BaP) and copper (Cu) are two widespread environmental contaminants with known toxicity towards mussels Mytilus spp. The effects of the individual and the interaction of BaP and Cu exposures were assessed in mussels Mytilus galloprovincialis using proteomic analysis. Mussels were exposed to BaP [10 μg L −1 (0.396 μM)], and Cu [10 μg L −1 (0.16 μM)], as well as to their binary mixture (mixture) for a period of 7 days. Proteomic analysis showed different protein expression profiles associated to each selected contaminant condition. A non-additive combined effect was observed in mixture in terms of new and suppressed proteins. Proteins more drastically altered (new, suppressed and 2-fold differentially expressed) were excised and analyzed by mass spectrometry, and eighteen putatively identified. Protein identification demonstrated the different accumulation, metabolism and chemical interactions of BaP, Cu and their mixture, resulting in different modes of action. Proteins associated with adhesion and motility (catchin, twitchin and twitchin-like protein), cytoskeleton and cell structure (α-tubulin and actin), stress response (heat shock cognate 71, heat shock protein 70, putative C1q domain containing protein), transcription regulation (zinc-finger BED domain-containing and nuclear receptor

Impact of benzo(a)pyrene, Cu and their mixture on the proteomic response of Mytilus galloprovincialis

Energy Technology Data Exchange (ETDEWEB)

Maria, V.L., E-mail: vmaria@ualg.pt [CIMA, Faculty of Sciences and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Gomes, T., E-mail: tcgomes@ualg.pt [CIMA, Faculty of Sciences and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Barreira, L., E-mail: lbarreir@ualg.pt [CCMAR, Faculty of Sciences and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Bebianno, M.J., E-mail: mbebian@ualg.pt [CIMA, Faculty of Sciences and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

2013-11-15

Highlights: •Distinct protein expression profiles dependent of BaP and Cu accumulation, metabolism and chemical interactions in mussels, Mytilus galloprovincialis. •Processes that involve adhesion and motility, cytoskeleton and cell structure, stress response, transcription regulation and energy metabolism are common mechanisms. •Traditional (ATP synthase, GST, HSP and actin) and novel biomarkers for BaP (ZFP), Cu (chitin synthase) and mixture (MVP) exposures identified in mussels. -- Abstract: In natural waters, chemical interactions between mixtures of contaminants can result in potential synergistic and/or antagonic effects in aquatic animals. Benzo(a)pyrene (BaP) and copper (Cu) are two widespread environmental contaminants with known toxicity towards mussels Mytilus spp. The effects of the individual and the interaction of BaP and Cu exposures were assessed in mussels Mytilus galloprovincialis using proteomic analysis. Mussels were exposed to BaP [10 μg L{sup −1} (0.396 μM)], and Cu [10 μg L{sup −1} (0.16 μM)], as well as to their binary mixture (mixture) for a period of 7 days. Proteomic analysis showed different protein expression profiles associated to each selected contaminant condition. A non-additive combined effect was observed in mixture in terms of new and suppressed proteins. Proteins more drastically altered (new, suppressed and 2-fold differentially expressed) were excised and analyzed by mass spectrometry, and eighteen putatively identified. Protein identification demonstrated the different accumulation, metabolism and chemical interactions of BaP, Cu and their mixture, resulting in different modes of action. Proteins associated with adhesion and motility (catchin, twitchin and twitchin-like protein), cytoskeleton and cell structure (α-tubulin and actin), stress response (heat shock cognate 71, heat shock protein 70, putative C1q domain containing protein), transcription regulation (zinc-finger BED domain-containing and nuclear

Global warming and environmental contaminants in aquatic organisms: the need of the etho-toxicology approach.

Science.gov (United States)

Manciocco, Arianna; Calamandrei, Gemma; Alleva, Enrico

2014-04-01

Environmental contaminants are associated with a wide spectrum of pathological effects. Temperature increase affects ambient distribution and toxicity of these chemicals in the water environment, representing a potentially emerging problem for aquatic species with short-, medium- and long-term repercussions on human health through the food chain. We assessed peer-reviewed literature, including primary studies, review articles and organizational reports available. We focused on studies concerning toxicity of environmental pollutants within a global warming scenario. Existing knowledge on the effects that the increase of water temperature in a contaminated situation has on physiological mechanisms of aquatic organisms is presented. Altogether we consider the potential consequences for the human beings due to fish and shellfish consumption. Finally, we propose an etho-toxicological approach to study the effects of toxicants in conditions of thermal increase, using aquatic organisms as experimental models under laboratory controlled conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Analysis of environmental contamination resulting from catastrophic incidents: part 1. Building and sustaining capacity in laboratory networks.

Science.gov (United States)

Magnuson, Matthew; Ernst, Hiba; Griggs, John; Fitz-James, Schatzi; Mapp, Latisha; Mullins, Marissa; Nichols, Tonya; Shah, Sanjiv; Smith, Terry; Hedrick, Elizabeth

2014-11-01

Catastrophic incidents, such as natural disasters, terrorist attacks, and industrial accidents, can occur suddenly and have high impact. However, they often occur at such a low frequency and in unpredictable locations that planning for the management of the consequences of a catastrophe can be difficult. For those catastrophes that result in the release of contaminants, the ability to analyze environmental samples is critical and contributes to the resilience of affected communities. Analyses of environmental samples are needed to make appropriate decisions about the course of action to restore the area affected by the contamination. Environmental samples range from soil, water, and air to vegetation, building materials, and debris. In addition, processes used to decontaminate any of these matrices may also generate wastewater and other materials that require analyses to determine the best course for proper disposal. This paper summarizes activities and programs the United States Environmental Protection Agency (USEPA) has implemented to ensure capability and capacity for the analysis of contaminated environmental samples following catastrophic incidents. USEPA's focus has been on building capability for a wide variety of contaminant classes and on ensuring national laboratory capacity for potential surges in the numbers of samples that could quickly exhaust the resources of local communities. USEPA's efforts have been designed to ensure a strong and resilient laboratory infrastructure in the United States to support communities as they respond to contamination incidents of any magnitude. The efforts include not only addressing technical issues related to the best-available methods for chemical, biological, and radiological contaminants, but also include addressing the challenges of coordination and administration of an efficient and effective response. Laboratory networks designed for responding to large scale contamination incidents can be sustained by applying

Integrating Individual-Based Indices of Contaminant Effects

Directory of Open Access Journals (Sweden)

Christopher L. Rowe

2001-01-01

Full Text Available Habitat contamination can alter numerous biological processes in individual organisms. Examining multiple individual-level responses in an integrative fashion is necessary to understand how individual health or fitness reflects environmental contamination. Here we provide an example of such an integrated perspective based upon recent studies of an amphibian (the bullfrog, Rana catesbeiana that experiences several, disparate changes when larval development occurs in a trace element�contaminated habitat. First, we present an overview of studies focused on specific responses of individuals collected from, or transplanted into, a habitat contaminated by coal combustion residues (CCR. These studies have reported morphological, behavioral, and physiological modifications to individuals chronically interacting with sediments in the CCR-contaminated site. Morphological abnormalities in the oral and tail regions in contaminant-exposed individuals influenced other properties such as grazing, growth, and swimming performance. Behavioral changes in swimming activities and responses to stimuli appear to influence predation risk in the contaminant-exposed population. Significant changes in bioenergetics in the contaminated habitat, evident as abnormally high energetic expenditures for survival (maintenance costs, may ultimately influence production pathways (growth, energy storage in individuals. We then present a conceptual model to examine how interactions among the affected systems (morphological, behavioral, physiological may ultimately bring about more severe effects than would be predicted if the responses were considered in isolation. A complex interplay among simultaneously occurring biological changes emerges in which multiple, sublethal effects ultimately can translate into reductions in larval or juvenile survival, and thus reduced recruitment of juveniles into the population. In systems where individuals are exposed to low concentrations of

Toxicity assessment of industrial chemicals and airborne contaminants: transition from in vivo to in vitro test methods: a review.

Science.gov (United States)

Bakand, S; Winder, C; Khalil, C; Hayes, A

2005-12-01

Exposure to occupational and environmental contaminants is a major contributor to human health problems. Inhalation of gases, vapors, aerosols, and mixtures of these can cause a wide range of adverse health effects, ranging from simple irritation to systemic diseases. Despite significant achievements in the risk assessment of chemicals, the toxicological database, particularly for industrial chemicals, remains limited. Considering there are approximately 80,000 chemicals in commerce, and an extremely large number of chemical mixtures, in vivo testing of this large number is unachievable from both economical and practical perspectives. While in vitro methods are capable of rapidly providing toxicity information, regulatory agencies in general are still cautious about the replacement of whole-animal methods with new in vitro techniques. Although studying the toxic effects of inhaled chemicals is a complex subject, recent studies demonstrate that in vitro methods may have significant potential for assessing the toxicity of airborne contaminants. In this review, current toxicity test methods for risk evaluation of industrial chemicals and airborne contaminants are presented. To evaluate the potential applications of in vitro methods for studying respiratory toxicity, more recent models developed for toxicity testing of airborne contaminants are discussed.

Environmental projects. Volume 14: Removal of contaminated soil and debris

Science.gov (United States)

Kushner, Len

1992-01-01

Numerous diverse activities at the Goldstone Deep Space Communications Complex (GDSCC) are carried out in support of six parabolic dish antennas. Some of these activities can result in possible spills or leakages of hazardous materials and wastes stored both above ground in steel drums and below ground in underground storage tanks (UST's). These possible leaks or spills, along with the past practice of burial of solid debris and waste in trenches and pits, could cause local subsurface contamination of the soil. In 1987, the Jet Propulsion Laboratory (JPL), retained Engineering-Science, Inc. (E-S), Pasadena, California, to identify the specific local areas within the GDSCC with subsurface soil contamination. The E-S study determined that some of the soils at the Apollo Site and the Mars Site were contaminated with hydrocarbons, while soil at a nonhazardous waste dumpsite at the Mojave Base site was contaminated with copper. This volume is a JPL-expanded version of the PE209 E-S report, and it also reports that all subsurface contaminated soils at the GDSCC were excavated, removed, and disposed of in an environmentally acceptable way, and the excavations were backfilled and covered in accordance with accepted Federal, State, and local environmental rules and regulations.

Vermiremediation of Soils Contaminated with Mixture of Petroleum ...

African Journals Online (AJOL)

ADOWIE PERE

order to clean-up soil contaminated with gasoline, diesel and spent engine oil using an earthworm - Eisenia ... hydrocarbon (TPH) level every 24 hours over a period of 120 hours using gas chromatography. ... adverse effects. The need to ...

Contaminants as viral cofactors: assessing indirect population effects

Science.gov (United States)

Springman, Katherine R.; Kurath, Gael; Anderson, James J.; Emlen, John M.

2005-01-01

Current toxicological methods often miss contaminant effects, particularly when immune suppression is involved. The failure to recognize and evaluate indirect and sublethal effects severely limits the applicability of those methods at the population level. In this study, the Vitality model is used to evaluate the population level effects of a contaminant exerting only indirect, sublethal effects at the individual level. Juvenile rainbow trout (Oncorhynchus mykiss) were injected with 2.5 or 10.0 mg/kg doses of the model CYP1A inducer, β-naphthoflavone (BNF) as a pre-stressor, then exposed to a challenge dose of 102 or 104 pfu/fish of infectious hematopoietic necrosis virus (IHNV), an important viral pathogen of salmonids in North America. At the end of the 28-d challenge, the mortality data were processed according to the Vitality model which indicated that the correlation between the average rate of vitality loss and the pre-stressor dose was strong:R2 = 0.9944. Average time to death and cumulative mortality were dependent on the BNF dose, while no significant difference between the two viral dosages was shown, implying that the history of the organism at the time of stressor exposure is an important factor in determining the virulence or toxicity of the stressor. The conceptual framework of this model permits a smoother transfer of results to a more complex stratum, namely the population level, which allows the immunosuppressive results generated by doses of a CYP1A inducer that more accurately represent the effects elicited by environmentally-relevant contaminant concentrations to be extrapolated to target populations. The indirect effects of other environmental contaminants with similar biotransformation pathways, such as polycyclic aromatic hydrocarbons (PAH), could be assessed and quantified with this model and the results applied to a more complex biological hierarchy.

Environmental contaminants in the food chain, NWS Seal Beach and Seal Beach NWR

Energy Technology Data Exchange (ETDEWEB)

Ohlendorf, H.M.; Byron, E.R. [CH2M Hill, Sacramento, CA (United States); Freas, K.E. [CH2M Hill, San Jose, CA (United States); Casados, E.M.; Kidwell, J.J. [Naval Facilities Engineering Command, San Diego, CA (United States). SW Division

1994-12-31

The authors conducted a study to determine whether environmental contaminants occurred in fish and invertebrates at concentrations that could be harmful to birds feeding in the estuarine salt marsh at Seal Beach National Wildlife Refuge (NWR), which is part of Naval Weapons Station (NWS) Seal Beach. Management of the refuge is focused primarily on endangered species, especially the light-footed clapper rail and the California least tern. Important food-chain organisms taken by rails (e.g., crabs and snails) and least terns (small fish) were sampled and analyzed for inorganic and organic contaminants that might be related to Navy activities at the Station. Results indicated that those contaminants are not likely to have lethal effects on rails or terns, although some chemicals (including cadmium, chromium, copper, lead, zinc and DDE) occurred at elevated concentrations in portions of the marsh. Possible sublethal effects also were evaluated and will be discussed.

Photocatalytic Degradation Effect of μ-Dielectric Barrier Discharge Plasma Treated Titanium Dioxide Nanoparticles on Environmental Contaminant.

Science.gov (United States)

Seo, Hyeon Jin; Hwang, Ki-Hwan; Na, Young Hoon; Boo, Jin-Hyo

2018-09-01

This study focused on the photocatalytic degradation effect of the μ-dielectric barrier discharge (μ-DBD) plasma treated titanium dioxide (TiO2) nanoparticles on environmental contaminant such as formaldehyde. TiO2 nanoparticles were treated by a μ-DBD plasma source with nitrogen gas. We analyzed the degradation of formaldehyde with the plasma treated TiO2 nanoparticles by UV-visible spectrophotometer (UV-VIS), and demonstrated that the photocatalytic activity of the μ-DBD plasma-treated TiO2 nanoparticles showed significantly high catalytic efficiency rather than without plasma treated TiO2 nanoparticles. Field emission scanning electron microscopes (FE-SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and water contact angle analyzer were used to measure the effects of photocatalytic degradation for the plasma treated TiO2 nanoparticles.

A prospect of the administration against problems of environmental contamination caused by radioactive nuclides

International Nuclear Information System (INIS)

Osako, Masahiro

2012-01-01

At first, focusing on the problem of radioactive contaminated wastes caused by Fukushima Daiichi Nuclear Accident, the Author described an outline of the waste management policy based on the law on special measures against the environmental contamination by radioactive nuclides. Next, the Author discussed a prospect of the environmental administration against the radioactive contamination problem. The most important mission of the environmental administration for the future must be to establish a social basis for the sustainable development, in other words the building-up of a newly social value added, through the measures against this unprecedented disaster. (author)

Bioremediation of oil sludge contaminated soil using bulking agent mixture enriched consortia of microbial inoculants based by irradiated compost

International Nuclear Information System (INIS)

Tri Retno, D.L.; Mulyana, N.

2013-01-01

Bulking agent mixture enriched consortia of microbial inoculants based by irradiated compost was used on bioremediation of microcosm scale contaminated by hydrocarbon soil. Bioremediation composting was carried out for 42 days. Composting was done with a mixture of bulking agent (sawdust, residual sludge biogas and compost) by 30%, mud petroleum (oil sludge) by 20% and 50% of soil. Mixture of 80% soil and 20% oil sludge was used as a control. Irradiated compost was used as a carrier for consortia of microbial inoculants (F + B) which biodegradable hydrocarbons. Treatment variations include A1, A2, B1, B2, C1, C2, D1 and D2. Process parameters were observed to determine the optimal conditions include: temperature, pH, water content, TPC (Total Plate Count) and degradation of % TPH (Total Petroleum Hydrocarbon). Optimal conditions were achieved in the remediation of oil sludge contamination of 20% using the B2 treatment with the addition consortia of microbial inoculants based by irradiated compost of sawdust (bulking agentby 30% at concentrations of soil by 50% with TPH degradation optimal efficiency of 81.32%. The result of GC-MS analysis showed that bioremediation for 42 days by using a sawdust as a mixture of bulking agents which enriched consortia of microbial inoculants based by irradiated compost is biodegradeable, so initial hydrocarbons with the distribution of the carbon chain C-7 to C-54 into final hydrocarbons with the distribution of carbon chain C-6 to C-8. (author)

Combined effects of pharmaceuticals, personal care products, biocides and organic contaminants on the growth of Skeletonema pseudocostatum.

Science.gov (United States)

Petersen, Karina; Heiaas, Harald Hasle; Tollefsen, Knut Erik

2014-05-01

Organisms in the environment are exposed to a number of pollutants from different compound groups. In addition to the classic pollutants like the polychlorinated biphenyls, polyaromatic hydrocarbons (PAHs), alkylphenols, biocides, etc. other compound groups of concern are constantly emerging. Pharmaceuticals and personal care products (PPCPs) can be expected to co-occur with other organic contaminants like biocides, PAHs and alkylphenols in areas affected by wastewater, industrial effluents and intensive recreational activity. In this study, representatives from these four different compound groups were tested individually and in mixtures in a growth inhibition assay with the marine algae Skeletonema pseudocostatum (formerly Skeletonema costatum) to determine whether the combined effects could be predicted by models for additive effects; the concentration addition (CA) and independent action (IA) prediction model. The eleven tested compounds reduced the growth of S. pseudocostatum in the microplate test in a concentration-dependent manner. The order of toxicity of these chemicals were irgarol>fluoxetine>diuron>benzo(a)pyrene>thioguanine>triclosan>propranolol>benzophenone 3>cetrimonium bromide>4-tert-octylphenol>endosulfan. Several binary mixtures and a mixture of eight compounds from the four different compound groups were tested. All tested mixtures were additive as model deviation ratios, the deviation between experimental and predicted effect concentrations, were within a factor of 2 from one or both prediction models (e.g. CA and IA). Interestingly, a concentration dependent shift from IA to CA, potentially due to activation of similar toxicity pathways at higher concentrations, was observed for the mixture of eight compounds. The combined effects of the multi-compound mixture were clearly additive and it should therefore be expected that PPCPs, biocides, PAHs and alkylphenols will collectively contribute to the risk in areas contaminated by such complex

Environmental simulation testing of solar cell contamination by hydrazine

Science.gov (United States)

Moore, W. W., Jr.

1972-01-01

Test results for thermal vacuum and radiation environment simulation of hydrazine contamination are discussed. Solar cell performance degradation, measured by short circuit current, is presented in correlation with the variations used in environmental parameters.

Widespread environmental contamination with Norwalk-like viruses (NLV) detected in a prolonged hotel outbreak of gastroenteritis.

Science.gov (United States)

Cheesbrough, J S; Green, J; Gallimore, C I; Wright, P A; Brown, D W

2000-08-01

A protracted outbreak of Norwalk-like virus (NLV)-associated gastroenteritis occurred in a large hotel in North-West England between January and May 1996. We investigated the pattern of environmental contamination with NLV in the hotel during and after the outbreak. In the ninth week, 144 environmental swabs taken from around the hotel were tested for NLV by nested RT-PCR. The sites were categorized according to the likelihood of direct contamination with vomit/faeces. The highest proportion of positive samples were detected in directly contaminated carpets, but amplicons were detected in sites above 1.5 m which are unlikely to have been contaminated directly. The trend in positivity of different sites paralleled the diminishing likelihood of direct contamination. A second environmental investigation of the same sites 5 months after the outbreak had finished were all negative by RT-PCR. This study demonstrates for the first time the extent of environmental contamination that may occur during a large NLV outbreak.

Environmental contamination with Staphylococcus aureus at a large, Midwestern university campus.

Science.gov (United States)

Thapaliya, Dipendra; Taha, Mohammed; Dalman, Mark R; Kadariya, Jhalka; Smith, Tara C

2017-12-01

Staphylococcus aureus can cause minor to severe life-threatening infections. The changing epidemiology of S. aureus is of public health concern due to the emergence of multi-drug resistant (MDR) strains. Environmental surfaces play a crucial role in the transmission of S. aureus. The objective of this study was to examine environmental contamination and molecular characteristics of S. aureus in health professional-associated (HPA) and non-health professional-associated (NHPA) buildings at a large university. A total of 152 environmental surface samples were collected from two HPA and two NHPA campus buildings. Bacterial culture and diagnostics were done using standard microbiology methods. Polymerase chain reaction was conducted to detect mecA and PVL genes. All isolates were spa typed. A subset of isolates was characterized via multi-locus sequence typing (MLST). All S. aureus isolates were tested for antibiotic susceptibility. The overall contamination of S. aureus and methicillin-resistant S. aureus (MRSA) was 22.4% (34/152) and 5.9% (9/152) respectively. Similar prevalence of contamination was found in HPA and NHPA buildings. A total of 17 different spa types were detected among 34 S. aureus isolates. The majority of the MRSA isolates belonged to clonal complex (CC) 8. One isolate was positive for PVL. Eleven different sequence types (STs) were detected from 17 tested isolates. ST8 was the most common. Twelve isolates (35.3%) were MDR. Almost 27% (9/34) of the isolates were MRSA. The highest contamination of S. aureus was found in high hand-touch areas such as door knobs, suggesting that human interaction in crowded environments such as academic institutions plays a crucial role in S. aureus/MRSA transmission via inanimate objects. Additionally, more than one-third of the isolates were MDR. These data reinforce the need to implement effective prevention strategies outside the healthcare setting to decrease the incidence of drug-resistant S. aureus infections

Effects of contaminants of emerging concern on Megaselia scalaris (Lowe, Diptera: Phoridae) and its microbial community.

Science.gov (United States)

Pennington, Marcus J; Rothman, Jason A; Jones, Michael B; McFrederick, Quinn S; Gan, Jay; Trumble, John T

2017-08-15

Drought, rising temperatures, and expanding human populations are increasing water demands. Many countries are extending potable water supplies by irrigating crops with wastewater. Unfortunately, wastewater contains biologically active, long-lived pharmaceuticals, even after treatment. Run-off from farms and wastewater treatment plant overflows contribute high concentrations of pharmaceuticals to the environment. This study assessed the effects of common pharmaceuticals on a cosmopolitan saprophagous insect, Megaselia scalaris (Diptera: Phoridae). Larvae were reared on artificial diets spiked with contaminants of emerging concern (CECs) at environmentally relevant concentrations. Female flies showed no oviposition preference for treated or untreated diets. Larvae exposed to caffeine in diets showed increased mortality, and larvae fed antibiotics and hormones showed signs of slowed development, especially in females. The normal sex ratio observed in M. scalaris from control diets was affected by exposure to caffeine and pharmaceutical mixture treatments. There was an overall effect of treatment on the flies' microbial communities; notably, caffeine fed insects displayed higher microbial variability. Eight bacterial families accounted for approximately 95% of the total microbes in diet and insects. Our results suggest that CECs at environmentally relevant concentrations can affect the biology and microbial communities of an insect of ecological and medical importance.

Reduction in Clostridium difficile environmental contamination by hospitalized patients treated with fidaxomicin.

Science.gov (United States)

Biswas, J S; Patel, A; Otter, J A; Wade, P; Newsholme, W; van Kleef, E; Goldenberg, S D

2015-07-01

Fidaxomicin is sporicidal and may be associated with a reduced time to resolution of diarrhoea when used to treat patients with Clostridium difficile infection (CDI). This study investigated whether fidaxomicin for treatment of all patients with CDI reduced C. difficile environmental contamination. Surfaces in the rooms of 66 hospitalized patients treated with metronidazole and/or vancomycin and 68 hospitalized patients treated with fidaxomicin were sampled. Patients treated with fidaxomicin were less likely to contaminate their environment (25/68, 36.8%) than patients treated with metronidazole and/or vancomycin (38/66 57.6%) (P = 0.02). Treatment with fidaxomicin was associated with reduced environmental contamination with C. difficile. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Circulating levels of environmental contaminants are associated with dietary patterns in older adults.

Science.gov (United States)

Ax, Erika; Lampa, Erik; Lind, Lars; Salihovic, Samira; van Bavel, Bert; Cederholm, Tommy; Sjögren, Per; Lind, P Monica

2015-02-01

Food intake contributes substantially to our exposure to environmental contaminants. Still, little is known about our dietary habits' contribution to exposure variability. The aim of this study was to assess circulating levels of environmental contaminants in relation to predefined dietary patterns in an elderly Swedish population. Dietary data and serum concentrations of environmental contaminants were obtained from 844 70-year-old Swedish subjects (50% women) in the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study. Dietary data from 7-day food records was used to assess adherence to a Mediterranean-like diet, a low carbohydrate-high protein diet and the WHO dietary recommendations. Circulating levels of 6 polychlorinated biphenyl markers, 3 organochlorine pesticides, 1 dioxin and 1 polybrominated diphenyl ether, the metals cadmium, lead, mercury and aluminum and serum levels of bisphenol A and 4 phthalate metabolites were investigated in relation to dietary patterns in multivariate linear regression models. A Mediterranean-like diet was positively associated with levels of several polychlorinated biphenyls (118, 126, 153, and 209), trans-nonachlor and mercury. A low carbohydrate-high protein diet was positively associated with polychlorinated biphenyls 118 and 153, trans-nonachlor, hexachlorobenzene and p, p'-dichlorodiphenyldichloroethylene, mercury and lead. The WHO recommended diet was negatively related to levels of dioxin and lead, and borderline positively to polychlorinated biphenyl 118 and trans-nonachlor. Dietary patterns were associated in diverse manners with circulating levels of environmental contaminants in this elderly Swedish population. Following the WHO dietary recommendations seems to be associated with a lower burden of environmental contaminants. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluation of environmental samples containing heavy hydrocarbon components in environmental forensic investigations

Energy Technology Data Exchange (ETDEWEB)

Raia, J.C.; Blakley, C.R.; Fuex, A.N.; Villalanti, D.C.; Fahrenthold, P.D. [Triton Anal Corp, Houston, TX (United States)

2004-03-01

This article presents a procedure to evaluate and characterize environmental samples containing mixtures of hydrocarbons over a wide boiling range of materials that include fuels and other products used in commerce. The range of the method extends to the higher boiling and heavier molecular weight hydrocarbon products in the range of motor oil, bunker fuel, and heavier residue materials. The procedure uses the analytical laboratory technique of high-temperature simulated distillation along with mathematical regression of the analytical data to estimate the relative contribution of individual products in mixtures of hydrocarbons present in environmental samples. An analytical technique to determine hydrocarbon-type distributions by gas chromatography-mass spectrometry with nitric oxide ionization spectrometry evaluation is also presented. This type of analysis allows complex hydrocarbon mixtures to be classified by their chemical composition, or types of hydrocarbons that include paraffins, cycloparaffins, monoaromatics, and polycyclic aromatic hydrocarbons. Characteristic hydrocarbon patterns for example, in the relative distribution of polycyclic aromatic hydrocarbons are valuable for determining the potential origin of materials present in environmental samples. These methods provide quantitative data for hydrocarbon components in mixtures as a function of boiling range and 'hydrocarbon fingerprints' of the types of materials present. This information is valuable in assessing environmental impacts of hydrocarbons at contaminated sites and establishing the liabilities and cost allocations for responsible parties.

An Environmentally Friendly, Cost-Effective Determination of Lead in Environmental Samples Using Anodic Stripping Voltammetry

Science.gov (United States)

Goldcamp, Michael J.; Underwood, Melinda N.; Cloud, Joshua L.; Harshman, Sean

2008-01-01

Contamination of the environment with heavy metals such as lead presents many health risks. Simple, effective, and field-portable methods for the measurement of toxic metals in environmental samples are vital tools for evaluating the risks that these contaminants pose. This article describes the use of new developments in anodic stripping…

Microflora and mycotoxin contamination in poultry feed mixtures from western Poland.

Science.gov (United States)

Cegielska-Radziejewska, Renata; Stuper-Szablewska, Kinga; Szablewski, Tomasz

2013-01-01

Contamination of feeds with pathogenic microflora and mycotoxins constitutes a serious threat both for animals and humans. The aim of the study was to determine the degree of risk of the occurrence of microscopic fungi, selected bacteria and mycotoxins from the trichothecene group in poultry feeds in western Poland. In feed mixtures, the concentration of ergosterol (ERG), being a specific quantitative biomarker for the content of microscopic fungi, was determined. Grower and finisher feeds were characterized by a higher count of bacteria and fungi in comparison to starter feeds. A considerable variation was found in the amount of ergosterol in analyzed feeds. Mean ergosterol content in feeds amounted to 19.34 mg/kg. The most common genera of fungi detected in the tested feeds included Aspergillus, Rhizopus and Mucor. Irrespective of the type of feed, the proportion of trichothecenes group B was five times higher than that of trichothecenes group A in relation to the total content of these mycotoxins in samples. In terms of the analyzed mycotoxins, feeds contained the highest concentration of deoxynivalenol (DON). A statistically significant correlation was shown between DON and ERG and between total trichothecenes and ERG. Recorded results indicate that the level of microbiological contamination in feeds for broiler chickens produced in western Poland is within the requirements of the binding standards.

Some Properties of Emulsified Asphalt Paving Mixture at Iraqi Environmental Conditions

Directory of Open Access Journals (Sweden)

Shakir.A.Al-Mishhadani* Hasan.H.Al-Baid

2014-04-01

Full Text Available Cold emulsified asphalt mixture is generally a mix made of emulsified asphalt withaggregate. Emulsified asphalt is manufactured from base asphalt, emulsifier agent and waterwith approximate percentage of 40% to 75% asphalt, 0.1% to 2.5% emulsifier and 25% to60% water plus some minor components. This study aims to use the cold emulsified asphaltmixtures for road construction and maintenance in Iraq as an alternative to the hot asphaltmixtures, due to its economical, practical and environmental advantages. This studyfocusedto test and evaluates the emulsified asphalt material properties to be used as paving mixture.The tested properties of emulsified asphalt mixture were bulk density, air voids, dry Marshallstability, wet Marshall stability, retained Marshall stability, flow tests and compared with thecommon used specification.The results indicate that the emulsified asphalt type cationic slowsetting low viscosity (CSS-1 is very suitable with quartz type of aggregate from Al-Nibaayquarry. From many trial mixes it is found that the best percentages of initial residual bitumencontent to produced adequateresults for coating test ,mixing ,compaction ,curing and Marshallstability were ranged from (2.5%, 3%,3.5%,4% and 4.5%, andthe optimum percentage is(3.5%.Finally it can be conducted that the emulsified asphalt mixture is a suitable alternativemixture to the hot asphalt mixture for road construction and maintenance in Iraq.  

Some Properties of Emulsified Asphalt Paving Mixture at Iraqi Environmental Conditions

Directory of Open Access Journals (Sweden)

Shakir.A.Al-Mishhadani

2014-02-01

Full Text Available Cold emulsified asphalt mixture is generally a mix made of emulsified asphalt withaggregate. Emulsified asphalt is manufactured from base asphalt, emulsifier agent and waterwith approximate percentage of 40% to 75% asphalt, 0.1% to 2.5% emulsifier and 25% to60% water plus some minor components. This study aims to use the cold emulsified asphaltmixtures for road construction and maintenance in Iraq as an alternative to the hot asphaltmixtures, due to its economical, practical and environmental advantages. This studyfocusedto test and evaluates the emulsified asphalt material properties to be used as paving mixture.The tested properties of emulsified asphalt mixture were bulk density, air voids, dry Marshallstability, wet Marshall stability, retained Marshall stability, flow tests and compared with thecommon used specification.The results indicate that the emulsified asphalt type cationic slowsetting low viscosity (CSS-1 is very suitable with quartz type of aggregate from Al-Nibaayquarry. From many trial mixes it is found that the best percentages of initial residual bitumencontent to produced adequateresults for coating test ,mixing ,compaction ,curing and Marshallstability were ranged from (2.5%, 3%,3.5%,4% and 4.5%, andthe optimum percentage is(3.5%.Finally it can be conducted that the emulsified asphalt mixture is a suitable alternativemixture to the hot asphalt mixture for road construction and maintenance in Iraq.

Multicenter study of environmental contamination with cyclophosphamide, ifosfamide, and methotrexate in 48 Canadian hospitals.

Science.gov (United States)

Poupeau, Céline; Tanguay, Cynthia; Caron, Nicolas J; Bussières, Jean-François

2018-01-01

Context Oncology workers are occupationally exposed to antineoplastic drugs. This exposure can induce adverse health effects. In order to reduce their exposure, contamination on surfaces should be kept as low as possible. Objectives To monitor environmental contamination with cyclophosphamide, ifosfamide, and methotrexate in oncology pharmacy and patient care areas in Canadian hospitals. To describe the impact of some factors that may limit contamination. Methods This is a descriptive study. Twelve standardized sites were sampled in each participating center (six in the pharmacy and six in patient care areas). Samples were analyzed for the presence of cyclophosphamide, ifosfamide, and methotrexate by ultra-performance liquid chromatography tandem mass spectrometry technology. Descriptive statistical analyses were done and results were compared with a Kolmogorov-Smirnov test for independent samples. Results In 2015, 48 hospitals participated in this study (48/202, 24%). Overall, 34% (181/525) of the samples were positive for cyclophosphamide, 8% (41/525) for ifosfamide, and 6% (31/525) for methotrexate. The 75th percentile value of cyclophosphamide surface concentration was 6.9 pg/cm 2 . For ifosfamide and methotrexate, they were lower than the limit of detection. Centers who prepared more antineoplastic drugs per year and centers who used more cyclophosphamide per year showed significantly higher surface contamination ( p contamination. Conclusion In comparison with other multicenter studies that were conducted in Canada, the concentration of antineoplastic drugs measured on surfaces is decreasing. Regular environmental monitoring is a good practice in order to maintain contamination as low as reasonably achievable.

Environmental viral contamination in a pediatric hospital outpatient waiting area: implications for infection control.

Science.gov (United States)

D'Arcy, Nikki; Cloutman-Green, Elaine; Klein, Nigel; Spratt, David A

2014-08-01

Nosocomial outbreaks of viral etiology are costly and can have a major impact on patient care. Many viruses are known to persist in the inanimate environment and may pose a risk to patients and health care workers. We investigate the frequency of environmental contamination with common health care-associated viruses and explore the use of torque-teno virus as a marker of environmental contamination. Environmental screening for a variety of clinically relevant viruses was carried out over 3 months in a UK pediatric hospital using air sampling and surface swabbing. Swabs were tested for the presence of virus nucleic acid by quantitative polymerase chain reactions. Viral nucleic acid was found on surfaces and in the air throughout the screening period, with adenovirus DNA being the most frequent. Door handles were frequently contaminated. Torque-teno virus was also found at numerous sites. Evidence of environmental contamination with viral pathogens is present in health care environments and may be indicative of an infectious virus being present. Screening for viruses should be included in infection control strategies. Torque-teno virus may provide a better marker of contamination and reduce time and cost of screening for individual viruses. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Assessment of the environmental radioactive contamination levels by depleted uranium after NATO aggression on FR Yugoslavia

International Nuclear Information System (INIS)

Pavlovic, S.; Pavlovic, R.; Markovic, S; Plecas, I.

2001-01-01

During NATO aggression on FR Yugoslavia various ammunition have been used, some of them for the first time. Among others, 30 mm bullets with depleted uranium (DU) penetrators have been used. Radioactivity contamination surveys have started during the war due to indications that DU is used in cruise missiles. Besides that, there were a lot of radioactivity analysis of food, drinking water etc. Some of the obtained results are presented in this paper. Depleted uranium ammunition can permanently contaminate environment and so produce effects on population. Relation of the international radiation and environmental protection standards and contamination levels are discussed as well. (author)

Evaluating legacy contaminants and emerging chemicals in marine environments using adverse outcome pathways and biological effects-directed analysis.

Science.gov (United States)

Hutchinson, Thomas H; Lyons, Brett P; Thain, John E; Law, Robin J

2013-09-30

Natural and synthetic chemicals are essential to our daily lives, food supplies, health care, industries and safe sanitation. At the same time protecting marine ecosystems and seafood resources from the adverse effects of chemical contaminants remains an important issue. Since the 1970s, monitoring of persistent, bioaccumulative and toxic (PBT) chemicals using analytical chemistry has provided important spatial and temporal trend data in three important contexts; relating to human health protection from seafood contamination, addressing threats to marine top predators and finally providing essential evidence to better protect the biodiversity of commercial and non-commercial marine species. A number of regional conventions have led to controls on certain PBT chemicals over several years (termed 'legacy contaminants'; e.g. cadmium, lindane, polycyclic aromatic hydrocarbons [PAHs] and polychlorinated biphenyls [PCBs]). Analytical chemistry plays a key role in evaluating to what extent such regulatory steps have been effective in leading to reduced emissions of these legacy contaminants into marine environments. In parallel, the application of biomarkers (e.g. DNA adducts, CYP1A-EROD, vitellogenin) and bioassays integrated with analytical chemistry has strengthened the evidence base to support an ecosystem approach to manage marine pollution problems. In recent years, however,the increased sensitivity of analytical chemistry, toxicity alerts and wider environmental awareness has led to a focus on emerging chemical contaminants (defined as chemicals that have been detected in the environment, but which are currently not included in regulatory monitoring programmes and whose fate and biological impacts are poorly understood). It is also known that natural chemicals (e.g. algal biotoxins) may also pose a threat to marine species and seafood quality. Hence complex mixtures of legacy contaminants, emerging chemicals and natural biotoxins in marine ecosystems represent

Chemical mixtures: Evaluation of risk for child-specific exposures in a multi-stressor environment

International Nuclear Information System (INIS)

Pohl, H.R.; Abadin, H.G.

2008-01-01

Evaluating the health impact from exposure to chemical mixtures is multifaceted. One component is exposure. Exposure, and consequently risk assessment for mixtures and chemicals in general, are often viewed in terms of a given exposure to a given population at a given location over a given time period. However, environmental exposures are present throughout human lifetime. As a result, an evaluation of risk must include the distinctive characteristics related to chemical exposures which will impact risk depending upon the particular life stage where exposure occurs. Risks to offspring may be associated with unique exposures in utero, during infancy, childhood, or adolescent periods. For example, exposure of infants to anthropogenic chemicals via breast milk may be of concern. The Agency for Toxic Substances and Disease Registry's (ATSDR's) approach to evaluating risks associated with exposure to mixtures of chemicals is presented. In addition to the breast milk issues, indoor exposure to combined air pollutants, drinking water contaminants, and soil and dust contaminants are discussed. The difference between a mixture's risk evaluation for children and adults is in the distinct exposure scenarios resulting from variations in behavior, physiology, and/or pharmacokinetics between adults and children rather than in the method for the specific mixtures evaluation per se

Design of an environmental site assessment template for open radioactive site contamination : a radioecological risk approach and case study

International Nuclear Information System (INIS)

Nguyen, T.

2004-01-01

To reduce redundancy, cost, and time, while at the same time ultimately increasing the effectiveness of the radioactive risk management process, a logical framework incorporating risk assessments (human cancer and environmental risks) into the environmental site assessment process was designed for radioactive open site contamination. Risk-based corrective action is becoming an increasingly more acceptable approach for the remediation of contaminated sites. In the past, cleanup goals were usually established without any regard to the risk involved, by mandating remediation goals based solely on maximum contamination levels. Now, a multi-stage environmental site assessment template has been developed on a radioecological approach. The template gives a framework for making environmentally sound decisions based on relevant regulations and guidelines. The first stage involves the comparison of the background screening activity level to the regulated activity level, the second stage involves the use of site-specific information to determine the risk involved with the contamination, and the third stage provides a remediation decision matrix based on results from the first two stages. This environmental site assessment template is unique because it incorporates the modified Canadian National Classification System for radioactive contaminated sites and two different types of risk assessments (human cancer risks and the newly designed ecological risk) into the decision making process. The template was used to assess a radiologically contaminated site at the Canadian Forces Base at Suffield (Alberta) as a case study, and it reaffirms the Department of National Defence's action as appropriate. This particular site is a Class 3, has an overall insignificant human cancer risk ( -6 ) and a low environmental risk, and conforms to all regulated guidelines. Currently, it is restricted and should be left as is, provided that the subsurface is not disturbed. (author)

ENVIRONMENTAL CONTAMINATION FROM WEAPON TESTS

Energy Technology Data Exchange (ETDEWEB)

none

1958-10-01

The program of the Atomic Energy Commission on environmental contamination from weapons tests is designed for the overall evaluation of the hazard to humans from test operations. It is limited to studies of the deposition of activity at long range rather than the problems associated with immediate, close-in fallout. The program has largely been a study of Sr{sup 90}, since considerations based on experience and measurement indicate that it is the isotope of greatest potential hazard. Data are presented pertinent to the monitoring of long-range fallout, particularly Sr{sup 90} and Cs{sup 137}. Values are tabulated for the fallout deposition, air concentrations, water concentrations, and the amounts in foods and human bone. In addition, results are given for some experimental investigations. The report of these results is not interpretative although certain papers that do attempt to interpret the present situation with respect to Sr{sup 90} in particular are reprinted. Bibliographies are presented covering the period since the 1957 hearings before the Joint Committee on Atomic Energy concerning the nature of radioactive fallout and its effects on man. A document list of submissions to the United Nations Scientific Committee on the Effects of Atomic Radiation is given to illustrate the work done in other countries. Several papers on the subject, which have not been generally available, are reprinted.

Environmental impact assessment of biofuel production on contaminated land - Swedish case studies

Energy Technology Data Exchange (ETDEWEB)

Andersson-Skoeld, Yvonne; Suer, Pascal [Swedish Geotechnical Institute, Linkoeping (Sweden); Blom, Sonja [FB Engineering AB, Goeteborg (Sweden); Bardos, Paul [r3 Environmental Technology Ltd, Reading (United Kingdom); Track, Thomas; Polland, Marcel [DECHEMA e. V., Frankfurt am Main (Germany)

2009-07-01

sites. The first site was small, 5000 m2. Weeding and harvest were done manually, and the alternative was excavation of the contaminated soil followed by landfilling. The second site was 12 ha. Salix Vinimalis cultivation was assumed as entirely machine- based, and the alternative was covering the entire site with 0.5 m clean soil. Transport of soil would constitute the major environmental costs for the conventional remediation alternatives (excavation or covering), and cause 60-90% of the energy use, waste, use of fossil resources, land surface occupation, global warming, acidification, photochemical smog formation, and the global human toxicity of water, soil and air. Soil transports would cause 40% of water use, and less than 10% of the environmental effect on soil use, odour or local human toxicity. We calculated with clean soil transport of 30 km and a landfill 22 km from the smaller site. Biofuel cultivation would cause a lower environmental cost for all effect categories above, even when soil transport was ignored. This was in spite of the higher fertiliser use and the increased car transport for biofuel production compared to excavation or covering. The amount of fuel needed for covering the larger area was roughly equivalent to the amount needed for the agricultural equipment for Salix Vinimalis cultivation, but the total energy need for the conventional remediation was higher. This includes e.g. the energy needed for the production of plastic groundwater wells, production of equipment, production of fertiliser etc. Demand for arable area would increase as a result of the increasing demand for food and the increasing demand for biofuels. This spurred a detailed look at the land surface needed for the remediation alternatives. Contaminated soil occupies surface itself, and remediation leads to the exploitation of land beyond the location as well. In this study, the surface required beyond Salix Vinimalis cultivation has been included. That is to say the land

Environmental impact assessment of biofuel production on contaminated land - Swedish case studies

Energy Technology Data Exchange (ETDEWEB)

Andersson-Skoeld, Yvonne; Suer, Pascal (Swedish Geotechnical Institute, Linkoeping (Sweden)); Blom, Sonja (FB Engineering AB, Goeteborg (Sweden)); Bardos, Paul (r3 Environmental Technology Ltd, Reading (United Kingdom)); Track, Thomas; Polland, Marcel (DECHEMA e. V., Frankfurt am Main (Germany))

2009-07-01

between the sites. The first site was small, 5000 m2. Weeding and harvest were done manually, and the alternative was excavation of the contaminated soil followed by landfilling. The second site was 12 ha. Salix Vinimalis cultivation was assumed as entirely machine- based, and the alternative was covering the entire site with 0.5 m clean soil. Transport of soil would constitute the major environmental costs for the conventional remediation alternatives (excavation or covering), and cause 60-90% of the energy use, waste, use of fossil resources, land surface occupation, global warming, acidification, photochemical smog formation, and the global human toxicity of water, soil and air. Soil transports would cause 40% of water use, and less than 10% of the environmental effect on soil use, odour or local human toxicity. We calculated with clean soil transport of 30 km and a landfill 22 km from the smaller site. Biofuel cultivation would cause a lower environmental cost for all effect categories above, even when soil transport was ignored. This was in spite of the higher fertiliser use and the increased car transport for biofuel production compared to excavation or covering. The amount of fuel needed for covering the larger area was roughly equivalent to the amount needed for the agricultural equipment for Salix Vinimalis cultivation, but the total energy need for the conventional remediation was higher. This includes e.g. the energy needed for the production of plastic groundwater wells, production of equipment, production of fertiliser etc. Demand for arable area would increase as a result of the increasing demand for food and the increasing demand for biofuels. This spurred a detailed look at the land surface needed for the remediation alternatives. Contaminated soil occupies surface itself, and remediation leads to the exploitation of land beyond the location as well. In this study, the surface required beyond Salix Vinimalis cultivation has been included. That is to say

Sublethal effects of a metal contamination due to uranium mine tailings in the three-spined stickleback (Gasterosteus aculeatus L.). Implication in the susceptibility to a biological stress

International Nuclear Information System (INIS)

Le Guernic, Antoine

2015-01-01

Uranium extraction has resulted in a remobilization of this actinide into mine surrounding ecosystems. Uses of metal salts during mining site rehabilitation, and the natural presence of metals have increased the metal contamination in hydro systems submitted to mine tailings. In situ experiments were conducted in two former French uranium mining sites. Three-spined stickleback caging was used to determine the sublethal effects of this metal mixture on this freshwater fish, as well as its effects on fish susceptibility to a sudden biological stress. This pollution, characterised by higher metal concentrations (especially for uranium), has led to an oxidative stress in sticklebacks visible through several bio-markers, and other effects dependent on the study site. The polymetallic contamination has modified the stickleback responses to the biological stress, by preventing their phagocytic and antioxidant responses. This work has reinforced the interest of the caging technique during environmental studies and that of immuno-markers in a multi-bio-marker approach. (author)

Effects of mixtures of dicamba and glyphosate on nontarget plants

Science.gov (United States)

New technologies are being developed using mixtures of herbicides to manage a broader variety of weeds in multiple herbicide resistant crops such as soybean and cotton. As part of its regulation of pesticides, the US Environmental Protection Agency considers environmental risks,...

Personal and household hygiene, environmental contamination, and health in undergraduate residence halls in New York City, 2011.

Science.gov (United States)

Miko, Benjamin A; Cohen, Bevin; Haxall, Katharine; Conway, Laurie; Kelly, Nicole; Stare, Dianne; Tropiano, Christina; Gilman, Allan; Seward, Samuel L; Larson, Elaine

2013-01-01

While several studies have documented the importance of hand washing in the university setting, the added role of environmental hygiene remains poorly understood. The purpose of this study was to characterize the personal and environmental hygiene habits of college students, define the determinants of hygiene in this population, and assess the relationship between reported hygiene behaviors, environmental contamination, and health status. 501 undergraduate students completed a previously validated survey assessing baseline demographics, hygiene habits, determinants of hygiene, and health status. Sixty survey respondents had microbiological samples taken from eight standardized surfaces in their dormitory environment. Bacterial contamination was assessed using standard quantitative bacterial culture techniques. Additional culturing for coagulase-positive Staphylococcus and coliforms was performed using selective agar. While the vast majority of study participants (n = 461, 92%) believed that hand washing was important for infection prevention, there was a large amount of variation in reported personal hygiene practices. More women than men reported consistent hand washing before preparing food (p = .002) and after using the toilet (p = .001). Environmental hygiene showed similar variability although 73.3% (n = 367) of subjects reported dormitory cleaning at least once per month. Contamination of certain surfaces was common, with at least one third of all bookshelves, desks, refrigerator handles, toilet handles, and bathroom door handles positive for >10 CFU of bacteria per 4 cm(2) area. Coagulase-positive Staphylococcus was detected in three participants' rooms (5%) and coliforms were present in six students' rooms (10%). Surface contamination with any bacteria did not vary by frequency of cleaning or frequency of illness (p>.05). Our results suggest that surface contamination, while prevalent, is unrelated to reported hygiene or health in the university setting

Small mammals as monitors of environmental contaminants

International Nuclear Information System (INIS)

Talmage, S.S.; Walton, B.T.

1991-01-01

The merit of using small mammals as monitors of environmental contaminants was assessed using data from the published literature. Information was located on 35 species of small mammals from 7 families used to monitor heavy metals, radionuclides, and organic chemicals at mine sites, industrial areas, hazardous and radioactive waste disposal sites, and agricultural and forested land. To document foodchain transfer of chemicals, concentrations in soil, vegetation, and invertebrates, where available, were included. The most commonly trapped North American species were Peromyscus leucopus, Blarina brevicauda, and Microtus pennsylvanicus. In these species, exposure to chemicals was determined from tissue residue analyses, biochemical assays, and cytogenetic assays. Where enough information was available, suitable target tissues, or biological assays for specific chemicals were noted. In general, there was a relationship between concentrations of contaminants in the soil or food, and concentrations in target tissues of several species. This relationship was most obvious for the nonessential heavy metals, cadmium, lead, and mercury and for fluoride. Kidney was the single best tissue for residue analyses of inorganic contaminants. However, bone should be the tissue of choice for both lead and fluorine. Exposure to lead was also successfully documented using biochemical and histopathological endpoints. Bone was the tissue of choice for exposure to 90Sr, whereas muscle was an appropriate tissue for 137Cs. For organic contaminants, exposure endpoints depended on the chemical(s) of concern. Liver and whole-body residue analyses, as well as enzyme changes, organ histology, genotoxicity, and, in one case, population dynamics, were successfully used to document exposure to these contaminants

Remediation of soil contaminated with pesticides by treatment with gamma radiation

International Nuclear Information System (INIS)

Santos, Janilson Silva

2009-01-01

The discharge of empty plastic packaging of pesticides can be an environmental concern mainly by soil contamination. Nowadays, Brazil figures in third place among the leading world pesticide markets. An understanding of the processes that affect the transport and fate of pesticides is crucial to assess their potential for contamination of soil and groundwater, and to develop efficient and cost-effective site management and soil remediation strategies. Due to its impact on soil remediation has made sorption a major topic of research on soil-pesticide interactions. The main objective of this study is the evaluation of the pesticides transferring from contaminated mixture of commercial polymeric packing of high-density polyethylene, HDPE, used in agriculture to soil and their removal by gamma irradiation. Two soil samples of argyles compositions and media composition were exposed to a mixture of commercial polymeric packing contaminated with the pesticides methomyl, dimethoate, carbofuran, methidathion, triazine, thiophos, atrazine, ametryne, endosulfan, chloropyrifos, thriazophos and trifluralin. The pesticides leaching from packaging to soil was homogeneous considering a experimental research. The radiation treatment presented high efficiency on removal pesticides from both soil, but it depends on the physical-chemical characteristics of the contaminated soil. The higher efficiency was obtained in soils with higher organic material and humidity. The higher efficiency was obtained for the medium texture soil, with 20 kGy all present pesticides were removed in all layers. In the case of argyles texture soil, it was necessary a 30 kGy to remove the totality of present pesticides. (author)

Dietary toxicity of field-contaminated invertebrates to marine fish: effects of metal doses and subcellular metal distribution.

Science.gov (United States)

Dang, Fei; Rainbow, Philip S; Wang, Wen-Xiong

2012-09-15

There is growing awareness of the toxicological effects of metal-contaminated invertebrate diets on the health of fish populations in metal-contaminated habitats, yet the mechanisms underlying metal bioaccumulation and toxicity are complex. In the present study, marine fish Terapon jurbua terepon were fed a commercial diet supplemented with specimens of the polychaete Nereis diversicolor or the clam Scrobicularia plana, collected from four metal-impacted estuaries (Tavy, Restronguet Creek, West Looe, Gannel) in southwest England, as environmentally realistic metal sources. A comparative toxicological evaluation of both invertebrates showed that fish fed S. plana for 21 d exhibited evident mortality compared to those fed N. diversicolor. Furthermore, a spatial effect on mortality was observed. Differences in metal doses rather than subcellular metal distributions between N. diversicolor and S. plana appeared to be the cause of such different mortalities. Partial least squares regression was used to evaluate the statistical relationship between multiple-metal doses and fish mortality, revealing that Pb, Fe, Cd and Zn in field-collected invertebrates co-varied most strongly with the observed mortality. This study provides a step toward exploring the underlying mechanism of dietary toxicity and identifying the potential causality in complex metal mixture exposures in the field. Copyright © 2012 Elsevier B.V. All rights reserved.

Monitoring of organic contaminants in sediments using low field proton nuclear magnetic resonance

Science.gov (United States)

Zhang, Chi; Rupert, Yuri

2016-04-01

The effective monitoring of soils and groundwater contaminated with organic compounds is an important goal of many environmental restoration efforts. Recent geophysical methods such as electrical resistivity, complex conductivity, and ground penetrating radar have been successfully applied to characterize organic contaminants in the subsurface and to monitor remediation process both in laboratory and in field. Low field proton nuclear magnetic resonance (NMR) is a geophysical tool sensitive to the molecular-scale physical and chemical environment of hydrogen-bearing fluids in geological materials and shows promise as a novel method for monitoring contaminant remediation. This laboratory research focuses on measurements on synthetic samples to determine the sensitivity of NMR to the presence of organic contaminants and improve understanding of relationships between NMR observables, hydrological properties of the sediments, and amount and state of contaminants in porous media. Toluene, a light non-aqueous phase liquid (LNAPL) has been selected as a representative organic contaminant. Three types of porous media (pure silica sands, montmorillonite clay, and various sand-clay mixtures with different sand/clay ratios) were prepared as synthetic sediments. NMR relaxation time (T2) and diffusion-relaxation (D - T2) correlation measurements were performed in each sediment saturated with water and toluene mixed fluid at assorted concentrations (0% toluene and 100% water, 1% toluene and 99% water, 5% toluene and 95% water, 25% toluene and 75% water, and 100% toluene and 0% water) to 1) understand the effect of different porous media on the NMR responses in each fluid mixture, 2) investigate the role of clay content on T2 relaxation of each fluid, 3) quantify the amount hydrocarbons in the presence of water in each sediment, and 4) resolve hydrocarbons from water in D - T2 map. Relationships between the compositions of porous media, hydrocarbon concentration, and hydraulic

Management of commercial high-level and transuranium-contaminated radioactive wastes. Environmental statement

International Nuclear Information System (INIS)

1974-09-01

This Draft Environmental Statement is issued to assess the environmental impact of the AEC's program to manage commercial high-level and transuranium-contaminated radioactive wastes. These are the types of commercial radioactive wastes for which AEC custody is required by present or anticipated regulations. The program consists of three basic parts: development of a Retrievable Surface Storage Facility (RSSF) for commercial high-level waste, using existing technology; evaluating geological formations and sites for the development of a Geological Disposal Pilot Plant (GDPP) which would lead to permanent disposal; and providing retrievable storage for the transuranium-contaminated waste pending availability of permanent disposal. Consideration has been given to all environmental aspects of the program, using waste generation projections through the year 2000. Radiological and other impacts of implementing the program are expected to be minimal, but will be discussed in further environmental statements which will support budget actions for specific repositories. The alternatives discussed in this Draft Environmental Statement are presented. (U.S.)

A method for determining allowable residual contamination levels of radionuclide mixtures in soil

International Nuclear Information System (INIS)

Napier, B.A.

1982-05-01

An important consideration in the disposal of radioactive wastes, and consequently in the preparation of plans for remedial actions at contaminated sites, is the amount of radioactive contamination that may be allowed to remain at any particular waste site. The allowable residual contamination level (ARCL) is dependent on the radiation dose limit imposed, the physical and environmental characteristics of the waste site, and the time at which exposure to the wastes is assumed to occur. The steps in generating an ARCL are generally as follows: (1) develop plausible, credible site-specific exposure scenario; (2) calculate maximum annual radiation doses to an individual for each radionuclide based on the existing physical characteristics of the waste site and the site-specific exposure scenario; (3) calculate the ARCL for the dose limit desired, including all radionuclides present, uncorrected for site cleanup or barrier considerations; and (4) apply any corrections for proposed cleanup activity or addition of barriers to waste migration or uptake to obtain the ARCL applicable to the proposed action. Use of this method allows appropriate application of resources to achieve uniform compliance with a single regulatory standard, i.e., a radiation dose rate limit. Application and modification of the ARCL method requires appropriate models of the environmental transport and fate of radionuclides. Example calculations are given for several specific waste forms and waste site types in order to demonstrate the technique and generate comparisons with other approaches

Mixtures of xenoestrogens disrupt estradiol-induced non-genomic signaling and downstream functions in pituitary cells.

Science.gov (United States)

Viñas, René; Watson, Cheryl S

2013-03-26

Our study examines the effects of xenoestrogen mixtures on estradiol-induced non-genomic signaling and associated functional responses. Bisphenol-A, used to manufacture plastic consumer products, and nonylphenol, a surfactant, are estrogenic by a variety of assays, including altering many intracellular signaling pathways; bisphenol-S is now used as a bisphenol-A substitute. All three compounds contaminate the environment globally. We previously showed that bisphenol-S, bisphenol-A, and nonylphenol alone rapidly activated several kinases at very low concentrations in the GH3/B6/F10 rat pituitary cell line. For each assay we compared the response of individual xenoestrogens at environmentally relevant concentrations (10-15 -10-7 M), to their mixture effects on 10-9 M estradiol-induced responses. We used a medium-throughput plate immunoassay to quantify phosphorylations of extracellular signal-regulated kinases (ERKs) and c-Jun-N-terminal kinases (JNKs). Cell numbers were assessed by crystal violet assay to compare the proliferative effects. Apoptosis was assessed by measuring caspase 8 and 9 activities via the release of the fluorescent product 7-amino-4-trifluoromethylcoumarin. Prolactin release was measured by radio-immunoassay after a 1 min exposure to all individual and combinations of estrogens. Individual xenoestrogens elicited phospho-activation of ERK in a non-monotonic dose- (fM-nM) and mostly oscillating time-dependent (2.5-60 min) manner. When multiple xenoestrogens were combined with nM estradiol, the physiologic estrogen's response was attenuated. Individual bisphenol compounds did not activate JNK, while nonylphenol did; however, the combination of two or three xenoestrogens with estradiol generated an enhanced non-monotonic JNK dose-response. Estradiol and all xenoestrogen compounds induced cell proliferation individually, while the mixtures of these compounds with estradiol suppressed proliferation below that of the vehicle control, suggesting a

Microplastic potentiates triclosan toxicity to the marine copepod Acartia tonsa (Dana)

DEFF Research Database (Denmark)

Syberg, Kristian; Nielsen, Anne; Khan, Farhan

2017-01-01

Microplastics (MP) are contaminants of environmental concern partly due to plastics ability to sorb and transport hydrophobic organic contaminants (HOC). The importance of this "vector effect" is currently being debated in the scientific community. This debate largely ignores that the co-exposure......Microplastics (MP) are contaminants of environmental concern partly due to plastics ability to sorb and transport hydrophobic organic contaminants (HOC). The importance of this "vector effect" is currently being debated in the scientific community. This debate largely ignores that the co......-exposures of MP and HOC are mixtures of hazardous agents, which can be addressed from a mixture toxicity perspective. In this study, mixture effects of polyethylene microbeads (MP) and triclosan (TCS) (a commonly used antibacterial agent in cosmetics) were assessed on the marine copepod Acartia tonsa. Data...... indicated that MP potentiate the toxicity of TCS, illustrating the importance of understanding the mixture interaction between plastics and HOC when addressing the environmental importance of the vector effect....

Radioisotope studies of some effects and interactions of trace contaminants

International Nuclear Information System (INIS)

1976-01-01

The coordinated programme of ''isotopic tracer-aided studies of the biological side-effects of foreign chemical residues in food and agriculture'', initiated in 1973, had involved the participation of 12 scientists from 10 countries. Pesticide residues, toxic metals, atmospheric sulphur dioxide were studied, and the use of radiotracer techniques as monitoring tools for existing contaminant levels or for their biological effects. The programme had been successful in the development and application of selected labelled substrate techniques. Specific aspects studied were the effects of environmental contaminants at the molecular level of the cell nucleus, the development and significance of radioimmunoassay procedure for trace contaminants, action and joint action of toxic elements, and the radiometric analysis of cholinesterase as an index of exposure to organophosphorus and carbamate pesticides. Ten papers were presented and 12 coordinated investigations discussed. A number of recommendations were made

EFFECT OF LUBRICANT CONTAMINATION ON THE PERFORMANCE AND RELIABILITY OF HEAT PUMPS CHARGED WITH R-407C.

Science.gov (United States)

The report gives results of the development of new data that can be used to determine the effect of mineral oil contamination on the reliability of a heat pump system operating with a new hydrofluorocarbon mixture and polyol ester lubricant, to assess any performance degradation ...

Agricultural sources of contaminants of emerging concern and adverse health effects on freshwater fish

Science.gov (United States)

Tillitt, Donald E.; Buxton, Herbert T.

2011-01-01

Agricultural contaminants of emerging concern (CECs) are generally thought of as certain classes of chemicals associated with animal feeding and production facilities. Veterinary pharmaceuticals used in animal food production systems represent one of the largest groups of CECs. In our review, we discuss the extensive increase in use of antibiotics in animal feeding operations (AFOs) around the world. AFOs are a major consumer of antibiotics and other veterinary pharmaceuticals and over the past decade there has been growing information on the occurrence, release, and fate of CECs from animal food production operations, including the application of pharmaceutical-containing manure to agricultural fields and releases from waste lagoons. Concentrations of CECs in surface and ground water in proximity to AFOs correspond to their presence in the AFO wastes. In many cases, the environmental concentrations of agriculturally-derived CECs are below toxicity thresholds. Hormones and hormone replacement compounds are a notable exception, where chemical concentrations near AFOs can exceed concentrations known to cause adverse effects on endocrine-related functions in fish. In addition, some agricultural pesticides, once thought to be safe to non-target organisms, have demonstrated endocrine-related effects that may pose threats to fish populations in agricultural regions. That is, we have pesticides with emerging concerns, thus, the concern is emerging and not necessarily the chemical. In this light, one must consider certain agricultural pesticides to be included in the list of CECs. Even though agricultural pesticides are routinely evaluated in regulatory testing schemes which have been used for decades, the potential hazards of some pesticides have only recently been emerging. Emerging concerns of pesticides in fish include interference with hormone signaling pathways; additive (or more than additive) effects from pesticide mixtures; and adverse population-level effects at

Evaluating legacy contaminants and emerging chemicals in marine environments using adverse outcome pathways and biological effects-directed analysis

International Nuclear Information System (INIS)

Hutchinson, Thomas H.; Lyons, Brett P.; Thain, John E.; Law, Robin J.

2013-01-01

Natural and synthetic chemicals are essential to our daily lives, food supplies, health care, industries and safe sanitation. At the same time protecting marine ecosystems and seafood resources from the adverse effects of chemical contaminants remains an important issue. Since the 1970s, monitoring of persistent, bioaccumulative and toxic (PBT) chemicals using analytical chemistry has provided important spatial and temporal trend data in three important contexts; relating to human health protection from seafood contamination, addressing threats to marine top predators and finally providing essential evidence to better protect the biodiversity of commercial and non-commercial marine species. A number of regional conventions have led to controls on certain PBT chemicals over several years (termed ‘legacy contaminants’; e.g. cadmium, lindane, polycyclic aromatic hydrocarbons [PAHs] and polychlorinated biphenyls [PCBs]). Analytical chemistry plays a key role in evaluating to what extent such regulatory steps have been effective in leading to reduced emissions of these legacy contaminants into marine environments. In parallel, the application of biomarkers (e.g. DNA adducts, CYP1A-EROD, vitellogenin) and bioassays integrated with analytical chemistry has strengthened the evidence base to support an ecosystem approach to manage marine pollution problems. In recent years, however, the increased sensitivity of analytical chemistry, toxicity alerts and wider environmental awareness has led to a focus on emerging chemical contaminants (defined as chemicals that have been detected in the environment, but which are currently not included in regulatory monitoring programmes and whose fate and biological impacts are poorly understood). It is also known that natural chemicals (e.g. algal biotoxins) may also pose a threat to marine species and seafood quality. Hence complex mixtures of legacy contaminants, emerging chemicals and natural biotoxins in marine ecosystems represent

Seasonal and size-related variation of subcellular biomarkers in quagga mussels (Dreissena bugensis) inhabiting sites affected by moderate contamination with complex mixtures of pollutants.

Science.gov (United States)

Ács, A; Vehovszky, Á; Győri, J; Farkas, A

2016-07-01

The size-related differences in subcellular biomarker responses were assessed in Dreissena bugensis mussels inhabiting harbours moderately affected by pollution with complex mixtures of heavy metals and polycyclic aromatic hydrocarbons (PAHs). Adult D. bugensis samples were collected from three harbours of Lake Balaton (Hungary) characterized by moderate shipping activity, and as reference site, from a highly protected remote area of the lake. Biomarkers of exposure (metallothioneins (MTs), ethoxyresorufin-o-deethylase (EROD)), oxidative stress (lipid peroxidation (LPO), DNA strand breaks (DNAsb)) and possible endocrine disruption (vitellogenin-like proteins (VTG)) were analysed in whole-tissue homogenates of differently sized groups of mussels in relation to environmental parameters and priority pollutants (heavy metals and polycyclic aromatic hydrocarbons). Integrated biomarker response (IBR) indices were calculated for biomarker responses gained through in situ measurements to signalize critical sites and to better distinguish natural tendencies from biological effects of contaminants. Biomarker responses showed close positive correlation in case of MT, EROD, LPO, and DNAsb and negative correlation with VTG levels with mussel shell length in autumn, when higher levels of biomarkers appeared, possibly due to natural lifecycle changes of animals.

Environmental geophysics and geochemistry for contamination mapping and monitoring 1

Energy Technology Data Exchange (ETDEWEB)

Lee, Tai Sup; Lee, Sang Kyu; Hong, Young Kook [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of); and others

1995-12-01

This study aims to provide the technologies which can be practically used for contamination mapping and monitoring. To accomplish this goal, the geophysical and geochemical expertise and techniques commonly used in the mineral resources exploration are employed. In the first year of the three-year-long project, the purpose of the study is to introduce the optimum methodologies among the geophysical and geochemical techniques to tackle the various cases of environmental contamination. To achieve the purpose, case studies of the developed countries were surveyed and analyzed through the various kinds of literatures. The followings are categorized to be solved by geophysical methods: 1) delineation of water system pollution by acid mine drainage and distributions of waste rocks in the closed mine area, 2) defining boundaries of subsurface contamination due to oil seepage, 3) zoning of sea water intrusion in the seashore or subsurface geology highly containing salt, 4) locating of buried metallic wastes such as pipes and drums which can cause the secondary pollution by corrosion, and 5) outlining of the subsurface area polluted by leachate from the landfill. To experiment the above items, various geophysical methods were applied to the corresponding test sites. From these experiments, the applicabilities of the respective geophysical method were analyzed, and the optimum methods were derived for the various pollution types. Furthermore, electric and electromagnetic surveys data processing software were developed to quantitatively interpret and highly resolve the geology. The environmental assignments which can be solved by geochemical methods include: 1) drainage pollution by coal mine effluents, 2)subsurface contamination of oil-spill, 3) sea water intrusion, 4) dispersion of toxic heavy metallic elements in the metal mines, and 5) radon environmental geochemistry. The appropriate test sites for applying the geochemical methods were selected. (Abstract Truncated)

Arsenic and dichlorvos: Possible interaction between two environmental contaminants.

Science.gov (United States)

Flora, Swaran J S

2016-05-01

Metals are ubiquitously present in the environment and pesticides are widely used throughout the world. Environmental and occupational exposure to metal along with pesticide is an area of great concern to both the public and regulatory authorities. Our major concern is that combination of these toxicant present in environment may elicit toxicity either due to additive or synergistic interactions or 'joint toxic actions' among these toxicants. It poses a rising threat to human health. Water contamination particularly ground water contamination with arsenic is a serious problem in today's scenario since arsenic is associated with several kinds of health problems, such arsenic associated health anomalies are commonly called as 'Arsenism'. Uncontrolled use and spillage of pesticides into the environment has resulted in alarming situation. Moreover serious concerns are being addressed due to their persistence in the environmental matrices such as air, soil and surface water runoff resulting in continuous exposure of these harmful chemicals to human beings and animals. Bio-availability of these environmental toxicants has been enhanced much due to anthropological activities. Dreadfully very few studies are available on combined exposures to these toxicants on the animal or human system. Studies on the acute and chronic exposure to arsenic and DDVP are well reported and well defined. Arsenic is a common global ground water contaminant while dichlorvos is one of the most commonly and widely employed organophosphate based insecticide used in agriculture, horticulture etc. There is thus a real situation where a human may get exposed to these toxicants while working in a field. This review highlights the individual and combined exposure to arsenic and dichlorvos on health. Copyright © 2016 Elsevier GmbH. All rights reserved.

Mixture toxicity of PBT-like chemicals

DEFF Research Database (Denmark)

Syberg, Kristian; Dai, Lina; Ramskov, Tina

addition is a suitable model for default estimations of mixture effects. One of the major challenges is therefore how to select specific chemicals for actual mixture toxicity assessments. Persistant chemicals are likely to be present in the environment for an extended period of time, thus increasing...... the likelihood of them being present in environmentally found mixtures. Persistant, bioaccumulative and toxic (PBT) chemicals are therefore a highly relevant group of chemicals to consider for mixture toxicity regulation. The present study evaluates to what extent a number of PBT-like chemicals posess concern...... beyond that of the individual components. Firstly, the effects of three chemicals with PBT-like properties (acetyl cedrene, pyrene and triclosan) was examined on the freshwater snail, Potamopyrgus antipodarum. Secondly, mixture bioaccumulation of the same three chemicals were assessed experimentally...

The effect of miscellaneous oral dosage forms on the environmental pollution of sulfonamides in pig holdings.

Science.gov (United States)

Stahl, Jessica; Zessel, Katrin; Schulz, Jochen; Finke, Jan Henrik; Müller-Goymann, Christel Charlotte; Kietzmann, Manfred

2016-04-01

Due to antibiotic treatment of humans and animals, the prevalence of bacterial resistances increases worldwide. Especially in livestock farming, large quantities of faeces contaminated with antibiotics pose a risk of the carryover of the active ingredient to the environment. Accordingly, the aim of the present study was the evaluation of the benefit of different oral dosage forms (powder, pellets, granula) in pigs concerning the environmental pollution of sulfadiazine. Two subtherapeutic dosages were evaluated in powder mixtures to gain information about their potential to pollute the pig barn. Furthermore, a new group of pigs was kept in the stable after powder feeding of another pig group to determine the possible absorption of environmentally distributed antibiotics. Pigs were orally treated with three dosage forms. Simultaneously, sedimentation and airborne dust were collected and plasma and urine levels were determined. All formulations result in comparable plasma and urine levels, but massive differences in environmental pollution (powder > pellets, granula). Pigs housing in a contaminated barn exhibit traces of sulfadiazine in plasma and urine. Using pharmaceutical formulations like pellets or granula, the environmental pollution of sulfonamides can significantly be diminished due to massive dust reduction during feeding.

Radioactive contamination in metal recycling industry - an environmental issue

International Nuclear Information System (INIS)

Agarwal, S.P.

2012-01-01

Metal recycling has become an important industrial activity worldwide; it is seen as being socially and environmentally beneficial because it conserves natural ore resources and saves energy. However, there have been several accidents over the past decades involving orphan radioactive sources or other radioactive material that were inadvertently collected as metal scrap that was destined for recycling. The consequences of these accidents have been serious with regard to the protection of people and the environment from the harmful effects of ionizing radiation as well as from an economic point of view. India produces and exports steel products to various countries. In the recent years there were rejection and return of steel products as they were found to be contaminated with trace quantities of radioactive materials. During investigation of incidents of radioactive contamination in steel products exported from India, it was observed that steel products are contaminated with low level radioactivity. Though radioactivity level in steel products is found to be too low to pose any significant hazards to the handling personnel or to the users or the public at large, its presence is undesirable and need to be probed as to how it has entered in the steel products. Atomic Energy Regulatory Board (AERB) has investigated the incidents of such nature in the recent past and it is gathered that the steel products are made out of steel produced in a foundry where metal scrap containing radioactive material has been used. In this talk, incidents of radioactive contamination, its roots cause, and its radiological impact on person, property and environment, lessons learnt, remedial measures and international concerns will be discussed

Individual and mixture effects of selected pharmaceuticals on larval development of the estuarine shrimp Palaemon longirostris.

Science.gov (United States)

González-Ortegón, Enrique; Blasco, Julian; Nieto, Elena; Hampel, Miriam; Le Vay, Lewis; Giménez, Luis

2016-01-01

Few ecotoxicological studies incorporate within the experimental design environmental variability and mixture effects when assessing the impact of pollutants on organisms. We have studied the combined effects of selected pharmaceutical compounds and environmental variability in terms of salinity and temperature on survival, development and body mass of larvae of the estuarine shrimp Palaemon longirostris. Drug residues found in coastal waters occur as mixture, and the evaluation of combined effects of simultaneously occurring compounds is indispensable for their environmental risk assessment. All larval stages of P. longirostris were exposed to the nonsteroidal anti-inflammatory drug (NSAID) diclofenac sodium (DS: 40 and 750 μg L(-1)), the lipid regulator clofibric acid (CA: 17 and 361 μg L(-1)) and the fungicide clotrimazole (CLZ: 0.14 and 4 μg L(-1)). We observed no effect on larval survival of P. longirostris with the tested pharmaceuticals. However, and in contrast to previous studies on larvae of the related marine species Palaemon serratus, CA affected development through an increase in intermoult duration and reduced growth without affecting larval body mass. These developmental effects in P. longirostris larvae were similar to those observed in the mixture of DS and CA confirming the toxic effects of CA. In the case of CLZ, its effects were similar to those observed previously in P. serratus: high doses affected development altering intermoult duration, tended to reduce the number of larval instars and decreased significantly the growth rate. This study suggests that an inter-specific life histories approach should be taken into account to assess the effect of emergent compounds in coastal waters. Copyright © 2015 Elsevier B.V. All rights reserved.

Concentration addition, independent action and generalized concentration addition models for mixture effect prediction of sex hormone synthesis in vitro.

Directory of Open Access Journals (Sweden)

Niels Hadrup

Full Text Available Humans are concomitantly exposed to numerous chemicals. An infinite number of combinations and doses thereof can be imagined. For toxicological risk assessment the mathematical prediction of mixture effects, using knowledge on single chemicals, is therefore desirable. We investigated pros and cons of the concentration addition (CA, independent action (IA and generalized concentration addition (GCA models. First we measured effects of single chemicals and mixtures thereof on steroid synthesis in H295R cells. Then single chemical data were applied to the models; predictions of mixture effects were calculated and compared to the experimental mixture data. Mixture 1 contained environmental chemicals adjusted in ratio according to human exposure levels. Mixture 2 was a potency adjusted mixture containing five pesticides. Prediction of testosterone effects coincided with the experimental Mixture 1 data. In contrast, antagonism was observed for effects of Mixture 2 on this hormone. The mixtures contained chemicals exerting only limited maximal effects. This hampered prediction by the CA and IA models, whereas the GCA model could be used to predict a full dose response curve. Regarding effects on progesterone and estradiol, some chemicals were having stimulatory effects whereas others had inhibitory effects. The three models were not applicable in this situation and no predictions could be performed. Finally, the expected contributions of single chemicals to the mixture effects were calculated. Prochloraz was the predominant but not sole driver of the mixtures, suggesting that one chemical alone was not responsible for the mixture effects. In conclusion, the GCA model seemed to be superior to the CA and IA models for the prediction of testosterone effects. A situation with chemicals exerting opposing effects, for which the models could not be applied, was identified. In addition, the data indicate that in non-potency adjusted mixtures the effects cannot

Evaluation of carriage and environmental contamination by carbapenem-resistant Acinetobacter baumannii.

Science.gov (United States)

Nutman, A; Lerner, A; Schwartz, D; Carmeli, Y

2016-11-01

We evaluated the sensitivity of surveillance cultures for carbapenem-resistant Acinetobacter baumannii (CRAB) in patients and in their environment. Patients with a CRAB-positive clinical culture were sampled within 7 days; the buccal mucosa and rectum were sampled using swabs, and skin was sampled using pre-moistened sterile sponges. Sponges were also used to sample the surrounding environment. Specimens were inoculated onto CHROMagar MDR Acinetobacter plates both directly and after overnight enrichment. CRAB load was scored semi-quantitatively and composite scores for patient colonization and environmental contamination were calculated. Thirty-four patients were included. Screening sensitivity was 28/34 (82%) for buccal mucosa, 30/34 (88%) for skin, and 25/34 (74%) for rectum. Combined sensitivity was 32/34 (94%). Among patients with CRAB-positive respiratory cultures, sensitivity for buccal mucosa was 20/20 (100%). Direct inoculation had excellent sensitivity: 25/28 (89%) for all three sites combined. In the subgroup of patients who did not have a respiratory source for CRAB, direct inoculation sensitivity was lower than among patients with CRAB-positive respiratory cultures: 5/8 (63%) versus 20/20 (100%). The environment of all patients was contaminated with CRAB. There was a positive correlation between the patient colonization score and the environmental contamination score (r = 0.63, p Environmental contamination is common and can be monitored. Implementing screening may facilitate infection control efforts to limit the spread of CRAB. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Experimental study of contamination by a mixture resulting from the combustion of sodium in the presence of plutonium oxide

International Nuclear Information System (INIS)

Metivier, H.; Masse, R.; Nenot, J.C.; Nolibe, D.; Lafuma, J.

1976-01-01

The introduction into industry of breeder reactors using liquid sodium as the coolant gives rise to fresh radiotoxicological problems; the most likely chemical form in which the plutonium and sodium mixture may be found after a possible accident is a soluble oxide of plutonium(VI) or plutonium(VII). The biological behaviour of such mixtures was analysed in rats and monkeys following parenteral administration. In the case of rats distribution in the organs was analysed from 30 minutes to 30 days following intramuscular contamination. In the monkeys the authors only analysed distribution in the organs after one month. The biological behaviour of the mixture is marked by very high plutonium solubility. The maximum burden in the organs attains roughly 20% of the quantity deposited both in monkeys and rats. The spread of the plutonium proceeds gradually from the day of administration; it indicates that a soluble form of plutonium is present for a long time. Also observed is an increasing osteotropic tendency in the diffusible form. The liver fraction is rapidly removed, if it is assumed that faecal excretion represents biliary excretion. In the experimental conditions selected, the spread of a liquid aerosol of the solution is rapid and constitutes about 10% of the quantity deposited in the airways at the end of inhalation. Treatment with DTPA makes it possible to reduce the body burden, but less efficiently than after contamination by Pu(IV). (author)

Older Adults' Perceptions of Nutrition as Protective Against Detrimental Effects of Environmental Pollution.

Science.gov (United States)

Dunn, Kristina; Gaetke, Lisa; Stephenson, Tammy; Brewer, Dawn

2017-08-01

The aging process makes older adults vulnerable to the detrimental health effects of environmental contaminants. Our study assessed older adults' perceptions regarding diet being protective against environmental contaminants, their levels of concern about exposure, and their interest in learning about protective food-related strategies. A needs assessment to collect such information has not been conducted among older adults. Health fair survey results showed that they perceived diet as beneficial against contaminants, were concerned about health implications of exposure, and were interested in learning how to protect health through diet-related strategies. Results suggest that a nutrition-focused curriculum addressing how dietary strategies can help protect against environmental contaminants is needed for Extension professionals.

Benthic diatom community response to environmental variables and metal concentrations in a contaminated bay adjacent to Casey Station, Antarctica

International Nuclear Information System (INIS)

Cunningham, Laura; Snape, Ian; Stark, Jonathan S.; Riddle, Martin J.

2005-01-01

This study examined the effects of anthropogenic contaminants and environmental variables on the composition of benthic diatom communities within a contaminated bay adjacent to an abandoned waste disposal site in Antarctica. The combination of geographical, environmental and chemical data included in the study explained all of the variation observed within the diatom communities. The chemical data, particularly metal concentrations, explained 45.9% of variation in the diatom communities, once the effects of grain-size and spatial structure had been excluded. Of the metals, tin explained the greatest proportion of variation in the diatom communities (28%). Tin was very highly correlated (R 2 > 0.95) with several other variables (copper, iron, lead, and sum of metals), all of which explained similarly high proportions of total variation. Grain-size data explained 23% of variation once the effects of spatial structure and the chemical data had been excluded. The pure spatial component explained only 1.8% of the total variance. The study demonstrates that much of the compositional variability observed in the bay can be explained by concentrations of metal contaminants

Insights into aquatic toxicities of the antibiotics oxytetracycline and ciprofloxacin in the presence of metal: Complexation versus mixture

International Nuclear Information System (INIS)

Zhang Yu; Cai Xiyun; Lang Xianming; Qiao Xianliang; Li Xuehua; Chen Jingwen

2012-01-01

Co-contamination of ligand-like antibiotics (e.g., tetracyclines and quinolones) and heavy metals prevails in the environment, and thus the complexation between them is involved in environmental risks of antibiotics. To understand toxicological significance of the complex, effects of metal coordination on antibiotics' toxicity were investigated. The complexation of two antibiotics, oxytetracycline and ciprofloxacin, with three heavy metals, copper, zinc, and cadmium, was verified by spectroscopic techniques. The antibiotics bound metals via multiple coordination sites and rendered a mixture of various complexation speciations. Toxicity analysis indicated that metal coordination did modify the toxicity of the antibiotics and that antibiotic, metal, and their complex acted primarily as concentration addition. Comparison of EC 50 values revealed that the complex commonly was highest toxic and predominately correlated in toxicity to the mixture. Finally, environmental scenario analysis demonstrated that ignoring complexation would improperly classify environmental risks of the antibiotics. - Highlights: ► The complex of antibiotic with metal is a mixture of various complexation modes. ► Antibiotic and metal act as various combined interactions when their complexation is ignored. ► Antibiotic, metal, and their complex act as concentration addition interaction. ► Complex commonly is the highest toxicant. ► Neglecting complexation renders improper classification of risks for antibiotics. - Antibiotic, heavy metal and their complex act primarily as concentration addition interaction and the complex commonly is highest toxic.

The environmental effects of dental amalgam.

Science.gov (United States)

Chin, G; Chong, J; Kluczewska, A; Lau, A; Gorjy, S; Tennant, M

2000-12-01

Dental amalgam is one of the most commonly used materials in restorative dentistry. However, one of its major components, mercury, is of particular concern due to its potential adverse effects on humans and the environment. In this review, the environmental impact of dental amalgam will be discussed, with particular reference to the effects attributed to its mercury component. Mercury commonly occurs in nature as sulfides and in a number of minerals. Globally, between 20,000-30,000 tons of mercury are discharged into the environment each year as a result of human activities. According to a recent German report, approximately 46 per cent of the freshly triturated amalgam is inserted as new amalgam restorations and the rest is waste. Depending on the presence of an amalgam separating unit, some of the generated amalgam-contaminated sludge is discharged into the sewage system. Lost or extracted teeth with amalgam fillings and amalgam-contaminated waste, such as trituration capsules and cotton rolls are discharged with the solid waste and, in most instances, are incinerated. Use of disinfectants containing oxidizing substances in dental aspirator kits may contribute to remobilization of mercury and its subsequent release into the environment. Nevertheless, dental mercury contamination is only a small proportion of terrestrial mercury (3-4 per cent), which is quite insignificant compared with industrial pollution and combustion of fossil fuels by vehicles. The environmental impact of dental mercury is mainly due to the poor management of dental amalgam waste. Proper collection of mercury-contaminated solid waste prevents the release of mercury vapour during combustion. In addition, the use of amalgam separating devices reduces the amount of amalgam-contaminated water released from dental clinics.

Pesticide mixtures in the Swedish streams: Environmental risks, contributions of individual compounds and consequences of single-substance oriented risk mitigation.

Science.gov (United States)

Gustavsson, Mikael; Kreuger, Jenny; Bundschuh, Mirco; Backhaus, Thomas

2017-11-15

This paper presents the ecotoxicological assessment and environmental risk evaluation of complex pesticide mixtures occurring in freshwater ecosystems in southern Sweden. The evaluation is based on exposure data collected between 2002 and 2013 by the Swedish pesticide monitoring program and includes 1308 individual samples, detecting mixtures of up to 53 pesticides (modal=8). Pesticide mixture risks were evaluated using three different scenarios for non-detects (best-case, worst-case and using the Kaplan-Meier method). The risk of each scenario was analyzed using Swedish Water Quality Objectives (WQO) and trophic-level specific environmental thresholds. Using the Kaplan-Meier method the environmental risk of 73% of the samples exceeded acceptable levels, based on an assessment using Concentration-Addition and WQOs for the individual pesticides. Algae were the most sensitive organism group. However, analytical detection limits, especially for insecticides, were insufficient to analyze concentrations at or near their WQO's. Thus, the risk of the analyzed pesticide mixtures to crustaceans and fish is systematically underestimated. Treating non-detects as being present at their individual limit of detection increased the estimated risk by a factor 100 or more, compared to the best-case or the Kaplan-Meier scenario. Pesticide mixture risks are often driven by only 1-3 compounds. However, the risk-drivers (i.e., individual pesticides explaining the largest share of potential effects) differ substantially between sites and samples, and 83 of the 141 monitored pesticides need to be included in the assessment to account for 95% of the risk at all sites and years. Single-substance oriented risk mitigation measures that would ensure that each individual pesticide is present at a maximum of 95% of its individual WQO, would also reduce the mixture risk, but only from a median risk quotient of 2.1 to a median risk quotient of 1.8. Also, acceptable total risk levels would still

Effect of the oyster contaminated in Salmonella typhimurium and Escherichia coli

International Nuclear Information System (INIS)

Brena V, M.

1992-08-01

In this work the effect of the oyster contaminated in the species of bacteria better studied by its genetic composition these are the Salmonella typhimurium and the Escherichia coli and that its have been starting point for later radiobiological studies in superior organisms. Of this its have arisen two general lines. The research about the genotoxic effect of substances or mixtures in bacteria with the collaboration of the groups of Drosophila and X-ray Fluorescence analysis and on the other hand the study of the low doses of radiation also in bacteria. It is also treated the topic about the genetic effect of aromatic hydrocarbons in different biological systems. (Author)

Chemical-gene interaction networks and causal reasoning for biological effects prediction and prioritization of contaminants for environmental monitoring and surveillance

Science.gov (United States)

Evaluating the potential human health and ecological risks associated with exposures to complex chemical mixtures in the environment is one of the main challenges of chemical safety assessment and environmental protection. There is a need for approaches that can help to integrat...

The endocrine disruption properties of an adipose contaminant mixture extracted from East Greenland polar bears studied in the H295R cell line

DEFF Research Database (Denmark)

Hjorth, R.; Letcher, R. J.; Blair, D.

been well described and especially the polar bear (Ursus maritimus) is recognized as being one of the most contaminated species in the Arctic. The present study investigated the in vitro endocrine disruptive effects of the POP mixture found in adipose tissue from 10 East Greenland polar bears collected...... (dehydroepiandrosterone and androstenedione). These results demonstrated comprehensive in vitro effects of POPs extracted from polar bear adipose tissue on key elements in the steroidogenesis, and identifies disruption of CYP17 activity as a mode of action. A POP-induced interference with CYP17 can potentially explain...... previously observed hormone levels in polar bears and could pose a risk to their reproductive health....

Molecular epidemiology and environmental contamination during an outbreak of parainfluenza virus 3 in a haematology ward.

Science.gov (United States)

Kim, T; Jin, C E; Sung, H; Koo, B; Park, J; Kim, S-M; Kim, J Y; Chong, Y P; Lee, S-O; Choi, S-H; Kim, Y S; Woo, J H; Lee, J-H; Lee, J-H; Lee, K-H; Shin, Y; Kim, S-H

2017-12-01

Although fomites or contaminated surfaces have been considered as transmission routes, the role of environmental contamination by human parainfluenza virus type 3 (hPIV-3) in healthcare settings is not established. To describe an hPIV-3 nosocomial outbreak and the results of environmental sampling to elucidate the source of nosocomial transmission and the role of environmental contamination. During an hPIV-3 outbreak between May and June 2016, environmental surfaces in contact with clustered patients were swabbed and respiratory specimens used from infected patients and epidemiologically unlinked controls. The epidemiologic relatedness of hPIV-3 strains was investigated by sequencing of the haemagglutinin-neuraminidase and fusion protein genes. Of 19 hPIV-3-infected patients, eight were haematopoietic stem cell recipients and one was a healthcare worker. In addition, four had upper and 12 had lower respiratory tract infections. Of the 19 patients, six (32%) were community-onset infections (symptom onset within environmental swabs up to 12 days after negative respiratory polymerase chain reaction conversion. At least one-third of a peak season nosocomial hPIV-3 outbreak originated from nosocomial transmission, with multiple importations of hPIV-3 from the community, providing experimental evidence for extensive environmental hPIV-3 contamination. Direct contact with the contaminated surfaces and fomites or indirect transmission from infected healthcare workers could be responsible for nosocomial transmission. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Fixation of soil surface contamination using natural polysaccharides

International Nuclear Information System (INIS)

Sackschewsky, M.R.

1993-09-01

Natural polysaccharides were evaluated as alternatives to commercially available dust-control agents for application in buried-waste and contaminated-soil remediation situations. Materials were identified and evaluated with specific criteria in mind: the materials must be environmentally benign and must not introduce any additional hazardous materials; they must be effective for at least 2 or 3 days, but they do not necessarily have to be effective for more than 2 to 3 weeks; they should be relatively resistant to light traffic; they must not interfere with subsequent soil treatment techniques, especially soil washing; and they must be relatively inexpensive. Two products, a pregelled potato starch and a mixture of carbohydrates derived from sugar beets, were selected for evaluation. Testing included small- and large-scale field demonstrations, laboratory physical property analyses, and wind-tunnel evaluations

Residual radioactive contamination from decommissioning: Technical basis for translating contamination levels to annual dose

International Nuclear Information System (INIS)

Kennedy, W.E. Jr.; Peloquin, R.A.

1990-01-01

This document describes the generic modeling of the total effective dose equivalent (TEDE) to an individual in a population from a unit concentration of residual radioactive contamination. Radioactive contamination inside buildings and soil contamination are considered. Unit concentration TEDE factors by radionuclide, exposure pathway, and exposure scenario are calculated. Reference radiation exposure scenarios are used to derive unit concentration TEDE factors for about 200 individual radionuclides and parent-daughter mixtures. For buildings, these unit concentration factors list the annual TEDE for volume and surface contamination situations. For soil, annual TEDE factors are presented for unit concentrations of radionuclides in soil during residential use of contaminated land and the TEDE per unit total inventory for potential use of drinking water from a ground-water source. Because of the generic treatment of potentially complex ground-water systems, the annual TEDE factors for drinking water for a given inventory may only indicate when additional site data or modeling sophistication are warranted. Descriptions are provided of the models, exposure pathways, exposure scenarios, parameter values, and assumptions used. An analysis of the potential annual TEDE resulting from reference mixtures of residual radionuclides is provided to demonstrate application of the TEDE factors. 62 refs., 5 figs., 66 tabs

Associations between prenatal cigarette smoke exposure and externalized behaviors at school age among Inuit children exposed to environmental contaminants.

Science.gov (United States)

Desrosiers, Caroline; Boucher, Olivier; Forget-Dubois, Nadine; Dewailly, Eric; Ayotte, Pierre; Jacobson, Sandra W; Jacobson, Joseph L; Muckle, Gina

2013-01-01

Smoking during pregnancy is common among Inuit women from the Canadian Arctic. Yet prenatal cigarette smoke exposure (PCSE) is seen as a major risk factor for childhood behavior problems. Recent data also suggest that co-exposure to neurotoxic environmental contaminants can exacerbate the effects of PCSE on behavior. This study examined the association between PCSE and behavior at school age in a sample of Inuit children from Nunavik, Québec, where co-exposure to environmental contaminants is also an important issue. Interactions with lead (Pb) and mercury (Hg), two contaminants associated with behavioral problems, were also explored. Participants were 271 children (mean age=11.3years) involved in a prospective birth-cohort study. PCSE was assessed through maternal recall. Assessment of child behavior was obtained from the child's classroom teacher on the Teacher Report Form (TRF) and the Disruptive Behavior Disorders Rating Scale (DBD). Exposure to contaminants was assessed from umbilical cord and child blood samples. Other confounders were documented by maternal interview. After control for contaminants and confounders, PCSE was associated with increased externalizing behaviors and attention problems on the TRF and higher prevalence of attention deficit hyperactivity disorder (ADHD) assessed on the DBD. No interactions were found with contaminants. This study extends the existing empirical evidence linking PCSE to behavioral problems in school-aged children by reporting these effects in a population where tobacco use is normative rather than marginal. Co-exposure to Pb and Hg do not appear to exacerbate tobacco effects, suggesting that these substances act independently. © 2013. Published by Elsevier Inc. All rights reserved.

Toxicogenomic responses in rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals and a synthetic mixture

International Nuclear Information System (INIS)

Finne, E.F.; Cooper, G.A.; Koop, B.F.; Hylland, K.; Tollefsen, K.E.

2007-01-01

As more salmon gene expression data has become available, the cDNA microarray platform has emerged as an appealing alternative in ecotoxicological screening of single chemicals and environmental samples relevant to the aquatic environment. This study was performed to validate biomarker gene responses of in vitro cultured rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals, and to investigate effects of mixture toxicity in a synthetic mixture. Chemicals used for 24 h single chemical- and mixture exposures were 10 nM 17α-ethinylestradiol (EE2), 0.75 nM 2,3,7,8-tetrachloro-di-benzodioxin (TCDD), 100 μM paraquat (PQ) and 0.75 μM 4-nitroquinoline-1-oxide (NQO). RNA was isolated from exposed cells, DNAse treated and quality controlled before cDNA synthesis, fluorescent labelling and hybridisation to a 16k salmonid microarray. The salmonid 16k cDNA array identified differential gene expression predictive of exposure, which could be verified by quantitative real time PCR. More precisely, the responses of biomarker genes such as cytochrome p4501A and UDP-glucuronosyl transferase to TCDD exposure, glutathione reductase and gammaglutamyl cysteine synthetase to paraquat exposure, as well as vitellogenin and vitelline envelope protein to EE2 exposure validated the use of microarray applied to RNA extracted from in vitro exposed hepatocytes. The mutagenic compound NQO did not result in any change in gene expression. Results from exposure to a synthetic mixture of the same four chemicals, using identical concentrations as for single chemical exposures, revealed combined effects that were not predicted by results for individual chemicals alone. In general, the response of exposure to this mixture led to an average loss of approximately 60% of the transcriptomic signature found for single chemical exposure. The present findings show that microarray analyses may contribute to our mechanistic understanding of single contaminant mode of action as well as

Toxicogenomic responses in rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals and a synthetic mixture

Energy Technology Data Exchange (ETDEWEB)

Finne, E.F. [Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo (Norway) and University of Oslo, Department of Biology, P.O. Box 1066, Blindern, N-0316 Oslo (Norway)]. E-mail: eivind.finne@niva.no; Cooper, G.A. [Centre for Biomedical Research, University of Victoria, BC V8P5C2 (Canada); Koop, B.F. [Centre for Biomedical Research, University of Victoria, BC V8P5C2 (Canada); Hylland, K. [Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo (Norway); University of Oslo, Department of Biology, P.O. Box 1066, Blindern, N-0316 Oslo (Norway); Tollefsen, K.E. [Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo (Norway)

2007-03-10

As more salmon gene expression data has become available, the cDNA microarray platform has emerged as an appealing alternative in ecotoxicological screening of single chemicals and environmental samples relevant to the aquatic environment. This study was performed to validate biomarker gene responses of in vitro cultured rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals, and to investigate effects of mixture toxicity in a synthetic mixture. Chemicals used for 24 h single chemical- and mixture exposures were 10 nM 17{alpha}-ethinylestradiol (EE2), 0.75 nM 2,3,7,8-tetrachloro-di-benzodioxin (TCDD), 100 {mu}M paraquat (PQ) and 0.75 {mu}M 4-nitroquinoline-1-oxide (NQO). RNA was isolated from exposed cells, DNAse treated and quality controlled before cDNA synthesis, fluorescent labelling and hybridisation to a 16k salmonid microarray. The salmonid 16k cDNA array identified differential gene expression predictive of exposure, which could be verified by quantitative real time PCR. More precisely, the responses of biomarker genes such as cytochrome p4501A and UDP-glucuronosyl transferase to TCDD exposure, glutathione reductase and gammaglutamyl cysteine synthetase to paraquat exposure, as well as vitellogenin and vitelline envelope protein to EE2 exposure validated the use of microarray applied to RNA extracted from in vitro exposed hepatocytes. The mutagenic compound NQO did not result in any change in gene expression. Results from exposure to a synthetic mixture of the same four chemicals, using identical concentrations as for single chemical exposures, revealed combined effects that were not predicted by results for individual chemicals alone. In general, the response of exposure to this mixture led to an average loss of approximately 60% of the transcriptomic signature found for single chemical exposure. The present findings show that microarray analyses may contribute to our mechanistic understanding of single contaminant mode of action as

Nuclear explosion and internal contamination; Explosion nucleaire et contamination interne

Energy Technology Data Exchange (ETDEWEB)

Aeberhardt, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1956-07-01

By the study of the conditions of internal contamination due to the radioactive mixture produced by a nuclear explosion, the parts played by the relative weights of the different elements and the mode of expression of the doses are considered. Only the knowledge of the weight composition of the contamination mixture and of its evolution as a function of time can provide the required basis for the study of its metabolism in the organism. The curves which give the composition of the fission product mixture - in number of nuclei - - as a function of time - have been established. These curves are applied to some practical examples, particularly relative to the nature of contamination, radiotoxicity of some elements and assessment of hazards. (author) [French] Etudiant les modalites de la contamination interne par les elements radioactifs apparus lors d'une explosion nucleaire, le role de la 'masse' et le mode d'expression des doses sont envisages. La connaissance de la composition en 'masse' du melange contaminant et de son evolution en fonction du temps peut seule apporter les bases necessaires a l'etude de son comportement dans l'organisme. Les courbes donnant la composition du melange de produits de fission - en nombre de noyaux - - en fonction du temps - ont ete etablies. Quelques applications pratiques, relatives en particulier a la nature de la contamination, a la radiotoxicite de certains elements et a l'evaluation de risque, sont envisagees a titre d'exemple. (auteur)

Use of coal ash in production of concrete containing contaminated sand

International Nuclear Information System (INIS)

Ezeldin, A.S.

1991-01-01

There are between 2 to 3.5 million underground storage tanks located throughout the nation. Most of these tanks, which store oils and gasolines, are leaking making them one of the primary sources of soil contamination. Adding coal ash or cement to contaminated soil has been used to obtain stationary and inert wastecrete. By using this procedure, stabilization (limiting the solubility and mobility of the contaminants) and solidification (producing a solid waste block) of contaminated soils are successfully achieved. This paper investigates another re-use option of coal ash and contaminated soils. An experimental study evaluating the effectiveness of using coal ash with oil contaminated sand in concrete production is presented. A control mix made of clean sand was designed to yield 500 psi of compressive strength. Sand, artificially contaminated with 3% by weight of motor oil, was used as clean sand replacement. Six concrete mixtures were tested in compression and flexure. The six mixtures were obtained by increasing the ratio of contaminated sand to clean sand, namely; 10%, 20% and 40% and by introducing coal ash to the concrete mixture, namely; 20% of the cement weight. The test results indicate that the inclusion of oil contaminated sand in concrete reduces the compressive and flexural strengths. However, this decrease in strength is compensated by introducing coal ash in the mixture. Regaining that strength offers the possibility of using such concrete as a construction material in special structural applications. More research is required to establish better understanding of that composite and suggest feasible applications

Conditions for effective removal of pyrene from an artificially contaminated soil using Pseudomonas aeruginosa 57SJ rhamnolipids

International Nuclear Information System (INIS)

Bordas, Francois; Lafrance, Pierre; Villemur, Richard

2005-01-01

The efficacy of a new rhamnolipid biosurfactants mixture to enhance the removal of pyrene from a soil artificially contaminated was investigated. The molar solubilization ratio (MSR) and the partition coefficient between the micelles and water (log K m ) were found to be 7.5 x 10 -3 and 5.7, respectively. From soil column studies, the pyrene removal increased linearly with the concentration of the injected biosurfactants solution above the effective critical micellar concentration (0.4 g L -1 ). Flushing with a 5.0 g L -1 biosurfactants solution increased the pyrene concentration in the effluent by 178 times. At high biosurfactants' concentrations (2.5 and 5.0 g L -1 ), the cumulative pyrene recovery reached 70%. This pyrene remobilization takes place independently of the soil organic carbon solubilization. This study provides a combination of batch and column experiments in order to find the conditions for effective soil remediation using a new rhamnolipids mixture. - The potential of newly isolated biosurfactants to mobilize PAHs from contaminated soils was evaluated from the determination in dynamic conditions of their effective critical micellar concentration

Description of source term data on contaminated sites and buildings compiled for the waste management programmatic environmental impact statement (WMPEIS)

International Nuclear Information System (INIS)

Short, S.M.; Smith, D.E.; Hill, J.G.; Lerchen, M.E.

1995-10-01

The U.S. Department of Energy (DOE) and its predecessor agencies have historically had responsibility for carrying out various national missions primarily related to nuclear weapons development and energy research. Recently, these missions have been expanded to include remediation of sites and facilities contaminated as a result of past activities. In January 1990, the Secretary of Energy announced that DOE would prepare a Programmatic Environmental Impact Statement on the DOE's environmental restoration and waste management program; the primary focus was the evaluation of (1) strategies for conducting remediation of all DOE contaminated sites and facilities and (2) potential configurations for waste management capabilities. Several different environmental restoration strategies were identified for evaluation, ranging from doing no remediation to strategies where the level of remediation was driven by such factors as final land use and health effects. A quantitative assessment of the costs and health effects of remediation activities and residual contamination levels associated with each remediation strategy was made. These analyses required that information be compiled on each individual contaminated site and structure located at each DOE installation and that the information compiled include quantitative measurements and/or estimates of contamination levels and extent of contamination. This document provides a description of the types of information and data compiled for use in the analyses. Also provided is a description of the database used to manage the data, a detailed discussion of the methodology and assumptions used in compiling the data, and a summary of the data compiled into the database as of March 1995. As of this date, over 10,000 contaminated sites and structures and over 8,000 uncontaminated structures had been identified across the DOE complex of installations

Mixtures of endocrine disrupting contaminants modelled on human high end exposures

DEFF Research Database (Denmark)

Christiansen, Sofie; Kortenkamp, A.; Petersen, Marta Axelstad

2012-01-01

exceeding 1 is expected to lead to effects in the rat, a total dose more than 62 times higher than human exposures should lead to responses. Considering the high uncertainty of this estimate, experience on lowest‐observed‐adverse‐effect‐level (LOAEL)/NOAEL ratios and statistical power of rat studies, we...... expected that combined doses 150 times higher than high end human intake estimates should give no, or only borderline effects, whereas doses 450 times higher should produce significant responses. Experiments indeed showed clear developmental toxicity of the 450‐fold dose in terms of increased nipple...... though each individual chemical is present at low, ineffective doses, but the effects of mixtures modelled based on human intakes have not previously been investigated. To address this issue for the first time, we selected 13 chemicals for a developmental mixture toxicity study in rats where data about...

Environmental hazard analysis - contamination of nutrients, mercury and cesium-137 in natural waters

International Nuclear Information System (INIS)

Hakanson, L.

1990-01-01

Results from some ongoing Swedish research projects on different types of contamination of limnic as well as marine areas are summarized. A brief theoretical outline on the central concepts of the 'meso-scale-type' of environmental hazard analysis, utilizing examples on eutrophication of coastal waters is given. The concepts are further substantiated in two subsequent parts dealing with radioactive cesium and mercury. The idea is to illustrate that the basic concepts for ('real' world/'meso scale') environmental hazard analysis can be used for different substances and different aquatic environments. It is important to give clear, quantifiable definitions of the effect, dose and environmental sensitivity parameters, which should be valid for a defined area and for a defined span of time. All other parameters should be compatible and have the same area and time resolution. (author)

The effect of environmental contamination on the community structure and fructification of ectomycorrhizal fungi.

Science.gov (United States)

Sun, Qibiao; Liu, Yaping; Yuan, Huatao; Lian, Bin

2017-02-01

Ectomycorrhizal fungi are an essential component of forest ecosystems, most of which can form edible and medical fruiting bodies. Although many studies have focused on the fructification of ectomycorrhizal fungi in phenology, the impact of environmental contamination, especially living garbage, on the formation of fruiting body is still unknown. A field investigation, combined with a high-throughput sequencing method, was used to study the effect of living garbage pollution on the fructification and hypogeous community structure of ectomycorrhizal fungi symbiosing with cedar (Cedrus deodara (Roxb.) G. Don). The results showed that garbage significantly altered soil abiotic and biotic properties, increasing soil urease activity, decreasing the soil exchangeable metal content and phosphatase activity, and ultimately inhibiting the formation of fruiting bodies. The pollution of garbage also changed the community structure of hypogeous ectomycorrhizal fungi where ectomycorrhizal ascomycetes dominated. In unpolluted sites, the relative abundance of ectomycorrhizal ascomycetes and basidiomycetes were almost equal. Although no fruiting bodies were observed in that soil polluted by living garbage, the sequencing result showed that various ectomycorrhizal fungi were present underground, suggesting that these taxonomic fungi had the potential to cope with adverse conditions. This study not only provided a deeper understanding of the relationship between ectomycorrhizal fungal communities and prevailing environmental conditions, but provided a new pathway for the excavation and utilization of the resource of antistress ectomycorrhizal fungi. © 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Effects of diuron and carbofuran and their mixtures on the microalgae Raphidocelis subcapitata.

Science.gov (United States)

Mansano, Adrislaine S; Moreira, Raquel A; Dornfeld, Hugo C; Freitas, Emanuela C; Vieira, Eny M; Sarmento, Hugo; Rocha, Odete; Seleghim, Mirna H R

2017-08-01

In aquatic environments, organisms are often exposed to mixtures of several pesticides. In this study, the effects of carbofuran and diuron and their mixtures on the microalgae Raphidocelis subcapitata were investigated. For this purpose, toxicity tests were performed with the single compounds (active ingredients and commercial formulations) and their combinations (only active ingredients). According to the results, the toxicity of active ingredients and their commercial formulations to R. subcapitata was similar. In the single exposures, both carbofuran and diuron inhibited significantly the R. subcapitata growth and caused physiological (chlorophyll a content) and morphological (complexity and cell size) changes in cells, as captured by flow cytometry single-cell properties. Regarding the mixture toxicity tests, data fitted to both reference models, concentration addition (CA) and independent action (IA), and evidenced significant deviations. After the CA fitting, dose-ratio dependent deviation had the best fit to the data, demonstrating synergism caused mainly by diuron and antagonism caused mainly by carbofuran. After fitting the IA model, a synergistic deviation represented the best fit for the diuron and carbofuran mixtures. In general, the two reference models indicated the occurrence of synergism in the mixtures of these compounds, especially when diuron was the dominant chemical in the combinations. The increased toxicity caused by the mixture of these pesticides could pose a greater environmental risk for phytoplankton. Thus, exposure to diuron and carbofuran mixtures must also be considered in risk assessments, since the combination of these compounds may result in more severe effects on algae population growth than single exposures. Copyright © 2017 Elsevier Inc. All rights reserved.

Predicting soil, water and air concentrations of environmental contaminants locally and regionally; multimedia transport and transformation models

International Nuclear Information System (INIS)

McKone, T.E.; Daniels, J.I.

1991-01-01

Environmental scientists recognize that the environment functions as a complex, interconnected system. A realistic risk-management strategy for many contaminants requires a comprehensive and integrated assessment of local and regional transport and transformation processes. In response to this need, we have developed multimedia models that simulate the movement and transformation of chemicals as they spread through air, water, biota, soils, sediments, surface water and ground water. Each component of the environment is treated as a homogeneous subsystem that can exchange water, nutrients, and chemical contaminants with other adjacent compartments. In this paper, we illustrate the use of multimedia models and measurements as tools for screening the potential risks of contaminants released to air and deposited onto soil and plants. The contaminant list includes the volatile organic compounds (VOCs) tetrachloroethylene (PCE) and trichloroethylene (TCE), the semi-volatile organic compound benzo(a)pyrene, and the radionuclides tritium and uranium-238. We examine how chemical properties effect both the ultimate route and quantity of human and ecosystem contact and identify sensitivities and uncertainties in the model results. We consider the advantages of multimedia models relative to environmental monitoring data. (au)

Toxicity of vapor phase petroleum contaminants to microbial degrader communities

International Nuclear Information System (INIS)

Long, S.C.; Davey, C.A.

1994-01-01

Petroleum products constitute the largest quantity of synthetic organic chemical products produced in the US. They are comprised of mostly hydrocarbon constituents from many different chemical classes including alkenes, cycloalkanes, aromatic compounds, and polyaromatic hydrocarbons. Many petroleum constituents are classified as volatile organic compounds or VOCs. Petroleum products also constitute a major portion of environmental pollution. One emerging technology, with promise for applications to VOCs in subsurface soil environments, is bioventing coupled with soil vapor extraction. These technologies involve volatilization of contaminants into the soil gas phase by injection and withdrawal of air. This air movement causes enhancement of the aerobic microbial degradation of the mobilized vapors by the indigenous populations. This study investigated the effects of exposure of mixed, subsurface microbial communities to vapor phase petroleum constituents or vapors of petroleum mixtures. Soil slurries were prepared and plated onto mineral salts agar plates and exposed to vapor phase contaminants at equilibrium with pure product. Representative n-alkane, branched alkane, cycloalkane, and aromatic compounds were tested as well as petroleum product mixtures. Vapor exposure altered the numbers and morphologies of the colonies enumerated when compared to controls. However, even at high, equilibrium vapor concentrations, microbial degrader populations were not completely inhibited

Biodegradation of hydrocarbon mixtures in surface waters at environmentally relevant levels - Effect of inoculum origin on kinetics and sequence of degradation

DEFF Research Database (Denmark)

Birch, Heidi; Hammershøj, Rikke Høst; Comber, Mike

2017-01-01

Biodegradation is a dominant removal process for many organic pollutants, and biodegradation tests serve as tools for assessing their environmental fate within regulatory risk assessment. In simulation tests, the inoculum is not standardized, varying in microbial quantity and quality, thereby...... potentially impacting the observed biodegradation kinetics. In this study we investigated the effect of inoculum origin on the biodegradation kinetics of hydrocarbons for five inocula from surface waters varying in urbanization and thus expected pre-exposure to petroleum hydrocarbons. A new biodegradation...... method for testing mixtures of hydrophobic chemicals at trace concentrations was demonstrated: Aqueous solutions containing 9 hydrocarbons were generated by passive dosing and diluted with surface water resulting in test systems containing native microorganisms exposed to test substances at ng...

Chemical mixtures in untreated water from public-supply wells in the U.S.--occurrence, composition, and potential toxicity.

Science.gov (United States)

Toccalino, Patricia L; Norman, Julia E; Scott, Jonathon C

2012-08-01

Chemical mixtures are prevalent in groundwater used for public water supply, but little is known about their potential health effects. As part of a large-scale ambient groundwater study, we evaluated chemical mixtures across multiple chemical classes, and included more chemical contaminants than in previous studies of mixtures in public-supply wells. We (1) assessed the occurrence of chemical mixtures in untreated source-water samples from public-supply wells, (2) determined the composition of the most frequently occurring mixtures, and (3) characterized the potential toxicity of mixtures using a new screening approach. The U.S. Geological Survey collected one untreated water sample from each of 383 public wells distributed across 35 states, and analyzed the samples for as many as 91 chemical contaminants. Concentrations of mixture components were compared to individual human-health benchmarks; the potential toxicity of mixtures was characterized by addition of benchmark-normalized component concentrations. Most samples (84%) contained mixtures of two or more contaminants, each at concentrations greater than one-tenth of individual benchmarks. The chemical mixtures that most frequently occurred and had the greatest potential toxicity primarily were composed of trace elements (including arsenic, strontium, or uranium), radon, or nitrate. Herbicides, disinfection by-products, and solvents were the most common organic contaminants in mixtures. The sum of benchmark-normalized concentrations was greater than 1 for 58% of samples, suggesting that there could be potential for mixtures toxicity in more than half of the public-well samples. Our findings can be used to help set priorities for groundwater monitoring and suggest future research directions for drinking-water treatment studies and for toxicity assessments of chemical mixtures in water resources. Published by Elsevier B.V.

Biodegradation and environmental behavior of biodiesel mixtures in the sea: An initial study.

Science.gov (United States)

DeMello, Jared A; Carmichael, Catherine A; Peacock, Emily E; Nelson, Robert K; Samuel Arey, J; Reddy, Christopher M

2007-07-01

Biodiesel, a mixture of fatty acid methyl esters (FAMEs) derived from animal fats or vegetable oils, is rapidly moving towards the mainstream as an alternative source of energy. However, the behavior of biodiesel, or blends of biodiesel with fossil diesel, in the marine environment have yet to be fully understood. Hence, we performed a series of initial laboratory experiments and simple calculations to evaluate the microbial and environmental fate of FAMEs. Aerobic seawater microcosms spiked with biodiesel or mixtures of biodiesel and fossil diesel revealed that the FAMEs were degraded at roughly the same rate as n-alkanes, and more rapidly than other hydrocarbon components. The residues extracted from these different microcosms became indistinguishable within weeks. Preliminary results from physical-chemical calculations suggest that FAMEs in biodiesel mixtures will not affect the evaporation rates of spilled petroleum hydrocarbons but may stabilize oil droplets in the water column and thereby facilitate transport.

Escherichia coli Contamination across Multiple Environmental Compartments (Soil, Hands, Drinking Water, and Handwashing Water) in Urban Harare: Correlations and Risk Factors.

Science.gov (United States)

Navab-Daneshmand, Tala; Friedrich, Max N D; Gächter, Marja; Montealegre, Maria Camila; Mlambo, Linn S; Nhiwatiwa, Tamuka; Mosler, Hans-Joachim; Julian, Timothy R

2018-03-01

Escherichia coli pathotypes (i.e., enteropathogenic and enterotoxigenic) have been identified among the pathogens most responsible for moderate-to-severe diarrhea in low- and middle-income countries (LMICs). Pathogenic E. coli are transmitted from infected human or animal feces to new susceptible hosts via environmental reservoirs such as hands, water, and soil. Commensal E. coli , which includes nonpathogenic E. coli strains, are widely used as fecal bacteria indicator, with their presence associated with increased likelihood of enteric pathogens and/or diarrheal disease. In this study, we investigated E. coli contamination in environmental reservoirs within households ( N = 142) in high-population density communities of Harare, Zimbabwe. We further assessed the interconnectedness of the environmental compartments by investigating associations between, and household-level risk factors for, E. coli contamination. From the data we collected, the source and risk factors for E. coli contamination are not readily apparent. One notable exception is the presence of running tap water on the household plot, which is associated with significantly less E. coli contamination of drinking water, handwashing water, and hands after handwashing. In addition, E. coli levels on hands after washing are significantly associated with handwashing water contamination, hand contamination before washing, and diarrhea incidence. Finally, we observed that animal ownership increases E. coli contamination in soil, and E. coli in soil are correlated with contamination on hands before washing. This study highlights the complexity of E. coli contamination in household environments within LMICs. More, larger, studies are needed to better identify sources and exposure pathways of E. coli -and enteric pathogens generally-to identify effective interventions.

EDCs Mixtures: A Stealthy Hazard for Human Health?

Directory of Open Access Journals (Sweden)

Edna Ribeiro

2017-02-01

Full Text Available Endocrine disrupting chemicals (EDCs are exogenous chemicals that may occur naturally (e.g., phytoestrogens, while others are industrial substances and plasticizers commonly utilized worldwide to which human exposure, particularly at low-doses, is omnipresent, persistent and occurs in complex mixtures. EDCs can interfere with/or mimic estrogenic hormones and, consequently, can simultaneously trigger diverse signaling pathways which result in diverse and divergent biological responses. Additionally, EDCs can also bioaccumulate in lipid compartments of the organism forming a mixed “body burden” of contaminants. Although the independent action of chemicals has been considered the main principle in EDCs mixture toxicity, recent studies have demonstrated that numerous effects cannot be predicted when analyzing single compounds independently. Co-exposure to these agents, particularly in critical windows of exposure, may induce hazardous health effects potentially associated with a complex “body burden” of different origins. Here, we performed an exhaustive review of the available literature regarding EDCs mixtures exposure, toxicity mechanisms and effects, particularly at the most vulnerable human life stages. Although the assessment of potential risks to human health due to exposure to EDCs mixtures is a major topic for consumer safety, information regarding effective mixtures effects is still scarce.

Nuclear explosion and internal contamination

International Nuclear Information System (INIS)

Aeberhardt, A.

1956-01-01

By the study of the conditions of internal contamination due to the radioactive mixture produced by a nuclear explosion, the parts played by the relative weights of the different elements and the mode of expression of the doses are considered. Only the knowledge of the weight composition of the contamination mixture and of its evolution as a function of time can provide the required basis for the study of its metabolism in the organism. The curves which give the composition of the fission product mixture - in number of nuclei - - as a function of time - have been established. These curves are applied to some practical examples, particularly relative to the nature of contamination, radiotoxicity of some elements and assessment of hazards. (author) [fr

Biological monitoring of environmental contaminants (plants). Executive summary

Energy Technology Data Exchange (ETDEWEB)

Burton, M.A.S.

1986-01-01

Knowledge of contaminant concentrations does not necessarily indicate their significance to plant populations and communities within ecosystems. Accumulation within plants facilitates analysis of contaminants which may be present at very low levels in the environment and may show the spatial distribution and changes in the level of contamination with time. Effects on species distribution within plant communities and visible injury to foliage may also be related to contamination. Species can be selected appropriate to the area and the contaminant to be monitored. Species used to investigate the input of contaminants from atmospheric deposition, for example, may differ from those used to assess transfer through food webs. Mosses and lichens have been particularly widely used in many countries to show distribution of metals and radionuclides on local and regional scales and of pesticide contamination. Visible injury to foliage of higher plant species may reflect atmospheric concentrations of gaseous pollutants and monitoring networks of transplanted sensitive species can provide information on contaminant levels on a regional scale. Changes in species composition, especially of lichens, have also been related to the degree of contamination.

Multisite Direct Determination of the Potential for Environmental Contamination of Urine Samples Used for Diagnosis of Sexually Transmitted Infections.

Science.gov (United States)

Andersson, Patiyan; Tong, Steven Y C; Lilliebridge, Rachael A; Brenner, Nicole C; Martin, Louise M; Spencer, Emma; Delima, Jennifer; Singh, Gurmeet; McCann, Frances; Hudson, Carolyn; Johns, Tracy; Giffard, Philip M

2014-09-01

The detection of a sexually transmitted infection (STI) agent in a urine specimen from a young child is regarded as an indicator of sexual contact. False positives may conceivably arise from the transfer of environmental contaminants in clinic toilet or bathroom facilities into urine specimens. The potential for contamination of urine specimens with environmental STI nucleic acid was tested empirically in the male and female toilets or bathrooms at 10 Northern Territory (Australia) clinics, on 7 separate occasions at each. At each of the 140 experiments, environmental contamination with Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis nucleic acid contamination was determined by swabbing 10 locations, and urine collection was simulated 5 times, using a (1) synthetic urine surrogate and (2) a standardized finger contamination procedure. The most contaminated toilets and bathrooms were in remote Indigenous communities. No contamination was found in the Northern Territory Government Sexual Assault Referral Centre clinics, and intermediate levels of contamination were found in sexual health clinics and in clinics in regional urban centres. The frequency of surrogate urine sample contamination was low but non-zero. For example, 4 of 558 of the urine surrogate specimens from remote clinics were STI positive. This is by far the largest study addressing the potential environmental contamination of urine samples with STI agents. Positive STI tests arising from environmental contamination of urine specimens cannot be ruled out. The results emphasize that urine specimens from young children taken for STI testing should be obtained by trained staff in clean environments, and duplicate specimens should be obtained if possible. © The Author 2013. Published by Oxford University Press on behalf of the Pediatric Infectious Diseases Society.

Mixtures of herbicides and metals affect the redox system of honey bees.

Science.gov (United States)

Jumarie, Catherine; Aras, Philippe; Boily, Monique

2017-02-01

The increasing loss of bee colonies in many countries has prompted a surge of studies on the factors affecting bee health. In North America, main crops such as maize and soybean are cultivated with extensive use of pesticides that may affect non-target organisms such as bees. Also, biosolids, used as a soil amendment, represent additional sources of metals in agroecosystems; however, there is no information about how these metals could affect the bees. In previous studies we investigated the effects of environmentally relevant doses of herbicides and metals, each individually, on caged honey bees. The present study aimed at investigating the effects of mixtures of herbicides (glyphosate and atrazine) and metals (cadmium and iron), as these mixtures represent more realistic exposure conditions. Levels of metal, vitamin E, carotenoids, retinaldehyde, at-retinol, retinoic acid isomers (9-cis RA, 13-cis RA, at-RA) and the metabolites 13-cis-4-oxo-RA and at-4-oxo-RA were measured in bees fed for 10 days with contaminated syrup. Mixtures of herbicides and cadmium that did not affect bee viability, lowered bee α- and β-carotenoid contents and increased 9-cis-RA as well as 13-cis-4-oxo-RA without modifying the levels of at-retinol. Bee treatment with either glyphosate, a combination of atrazine and cadmium, or mixtures of herbicides promoted lipid peroxidation. Iron was bioconcentrated in bees and led to high levels of lipid peroxidation. Metals also decreased zeaxanthin bee contents. These results show that mixtures of atrazine, glyphosate, cadmium and iron may affect different reactions occurring in the metabolic pathway of vitamin A in the honey bee. Copyright © 2016 Elsevier Ltd. All rights reserved.

Late-life effects on rat reproductive system after developmental exposure to mixtures of endocrine disrupters.

Science.gov (United States)

Isling, Louise Krag; Boberg, Julie; Jacobsen, Pernille Rosenskjold; Mandrup, Karen Riiber; Axelstad, Marta; Christiansen, Sofie; Vinggaard, Anne Marie; Taxvig, Camilla; Kortenkamp, Andreas; Hass, Ulla

2014-01-01

This study examined late-life effects of perinatal exposure of rats to a mixture of endocrine-disrupting contaminants. Four groups of 14 time-mated Wistar rats were exposed by gavage from gestation day 7 to pup day 22 to a mixture of 13 anti-androgenic and estrogenic chemicals including phthalates, pesticides, u.v.-filters, bisphenol A, parabens, and the drug paracetamol. The groups received vehicle (control), a mixture of all 13 chemicals at 150-times (TotalMix150) or 450-times (TotalMix450) high-end human exposure, or 450-times a mixture of nine predominantly anti-androgenic chemicals (AAMix450). Onset of puberty and estrous cyclicity at 9 and 12 months of age were assessed. Few female offspring showed significantly regular estrus cyclicity at 12 months of age in the TotalMix450 and AAMix450 groups compared with controls. In 19-month-old male offspring, epididymal sperm counts were lower than controls, and in ventral prostate an overrepresentation of findings related to hyperplasia was observed in exposed groups compared with controls, particularly in the group dosed with anti-androgens. A higher incidence of pituitary adenoma at 19 months of age was found in males and females in the AAMix450 group. Developmental exposure of rats to the highest dose of a human-relevant mixture of endocrine disrupters induced adverse effects late in life, manifested as earlier female reproductive senescence, reduced sperm counts, higher score for prostate atypical hyperplasia, and higher incidence of pituitary tumors. These delayed effects highlight the need for further studies on the role of endocrine disrupters in hormone-related disorders in aging humans.

Antialgal effects of five individual allelochemicals and their mixtures in low level pollution conditions.

Science.gov (United States)

Zuo, Shengpeng; Zhou, Shoubiao; Ye, Liangtao; Ding, Ying; Jiang, Xiaofeng

2016-08-01

An effective, environmentally friendly, and eco-sustainable approach for removing harmful microalgae is exploiting the allelopathic potential of aquatic macrophytes. In this study, we simulated field pollution conditions in the laboratory to investigate algal inhibition by allelochemicals, thereby providing insights into field practices. We tested five allelochemicals, i.e., coumarin, ρ-hydroxybenzoic acid, protocatechuic acid, stearic acid, and ρ-aminobenzenesulfonic acid, and a typical green alga, Chlorella pyrenoidosa, under two conditions. In the unpolluted treatment, individual allelochemicals had strong algal inhibition effects, where coumarin and ρ-hydroxybenzoic acid had greater potential for algal inhibition than protocatechuic acid, stearic acid, and ρ-aminobenzenesulfonic acid based on the 50 % inhibitory concentration. However, when two or three allelochemicals were mixed in specific proportions, the algal inhibition rate exceeded 80 %, thereby indicating allelopathic synergistic interactions. Mixtures of four or five allelochemicals had weak effects on algal inhibition, which indicated antagonistic interactions. Furthermore, the presence of low lead pollution significantly reduced the antialgal potential of individual allelochemicals, whereas the allelopathic synergistic interactions with mixtures between two or three allelochemicals were changed into antagonistic effects by low pollution. In particular, the allelopathic antagonistic interactions between four or five allelochemicals were increased by pollution. The allelopathic performance of these five allelochemicals may depend on various factors, such as the chemical species, mixture parameters, and algal strain. Thus, we found that low level pollution reduced the allelopathic inhibition of microalgae by allelochemicals. Therefore, the control of algae by the direct addition of allelochemicals should consider various environmental factors.

Evaluation of bio-materials’ rejuvenating effect on binders for high-reclaimed asphalt content mixtures

Directory of Open Access Journals (Sweden)

A. Jiménez del Barco-Carrión

2017-07-01

Full Text Available The interest in using bio-materials in pavement engineering has grown significantly over the last decades due to environmental concerns about the use of non-recoverable natural resources. In this paper, bio-materials are used together with Reclaimed Asphalt (RA to restore some of the properties of the aged bitumen present in mixtures with high RA content. For this purpose, two bio-materials are studied and compared to conventional and polymer modified bitumens. Blends of these materials with RA bitumen were produced and studied to simulate a 50% RA mixture. The rejuvenating effect of the two bio-materials on RA has been assessed and compared with the effect of the conventional binders. Apparent Molecular Weight Distribution of the samples (obtained by the ?-method and different rheological parameters were used for this purpose. Results revealed the power of bio-materials to rejuvenate RA bitumen, showing their capability to be used as fresh binders in high-RA content mixtures.

Evaluation of bio-materials’ rejuvenating effect on binders for high-reclaimed asphalt content mixtures

International Nuclear Information System (INIS)

Jiménez del Barco-Carrión, A.; Pérez-Martínez, M.; Themeli, A.; Lo Presti, D.; Marsac, P.; Pouget, S.; Hammoum, F.; Chailleux, E.; Airey, G.D.

2017-01-01

The interest in using bio-materials in pavement engineering has grown significantly over the last decades due to environmental concerns about the use of non-recoverable natural resources. In this paper, bio-materials are used together with Reclaimed Asphalt (RA) to restore some of the properties of the aged bitumen present in mixtures with high RA content. For this purpose, two bio-materials are studied and compared to conventional and polymer modified bitumens. Blends of these materials with RA bitumen were produced and studied to simulate a 50% RA mixture. The rejuvenating effect of the two bio-materials on RA has been assessed and compared with the effect of the conventional binders. Apparent Molecular Weight Distribution of the samples (obtained by the ?-method) and different rheological parameters were used for this purpose. Results revealed the power of bio-materials to rejuvenate RA bitumen, showing their capability to be used as fresh binders in high-RA content mixtures. [es

Effects of organic contaminants in sewage sludge on soil fertility, plants and animals

International Nuclear Information System (INIS)

Hall, J.E.; Sauerbeck, D.R.; L'Hermite, P.

1992-01-01

Sewage sludge production in Europe will continue to rise as a result of higher environmental standards, making disposal increasingly difficult in the future. A considerable part of this sludge is spread beneficially on agricultural land as an organic fertilizer, however, this outlet is very sensitive to the problems associated with the inorganic and organic contaminants which sludge inevitably contains. Much research has been devoted to the problems of contaminants in sludge and their potential effects on soil, plants, animals and man in recent years, and the European Commission's Concerted Action COST 681 has provided a valuable forum for the exchange of views and progress of research on sludge treatment and disposal. This book contains 19 papers presented to a joint meeting of Working Party 4 (Agricultural Value) and Working Party 5 (Environmental Effects) of COST 681, held at the German Federal Research Centre of Agriculture (FAL), Braunschweig on 6-8 June 1990. The meeting addressed two areas of current concern; the occurrence, behaviour and transfer of sludge-derived organic contaminants (Session 1), and the influence of inorganic and organic contaminants on soil micro-organisms and their activities (Session 2)

Multicenter study of environmental contamination with cyclophosphamide, ifosfamide, and methotrexate in 66 Canadian hospitals: A 2016 follow-up study.

Science.gov (United States)

Roland, C; Caron, N; Bussières, J F

2017-08-01

Oncology workers are occupationally exposed to antineoplastic drugs. This exposure can induce adverse health effects. To reduce their exposure, contamination on surfaces should be kept as low as possible. The main objective of this study was to monitor environmental contamination with cyclophosphamide, ifosfamide, and methotrexate in oncology pharmacy and patient care areas in Canadian centers. The secondary objective was to describe the impact of some factors that may limit contamination. This is a descriptive study. Twelve standardized sites were sampled in each participating center (six in the pharmacy and six in patient care areas). Samples were analyzed for the presence of cyclophosphamide, ifosfamide, and methotrexate by ultra-performance liquid chromatography-tandem mass spectrometry technology. Descriptive statistical analyses were done and results were compared with a Kolmogorov-Smirnov test for independent samples. In 2016, 66 centers participated in this study (66/202, 32.7%). Overall, 43.4% (326/752) of the samples were positive for cyclophosphamide, 13.2% (99/752) for ifosfamide and 6.9% (52/752) for methotrexate. The 75th percentile value of cyclophosphamide surface concentration was 6.8 pg/cm 2 and lower than the limit of detection for ifosfamide and methotrexate. Centers who prepared more antineoplastic drugs per year (p contamination to cyclophosphamide. Environmental surveillance is one part of a comprehensive approach for minimizing hazardous exposures in healthcare. This study highlights a low level of contamination of three hazardous drugs amongst 66 Canadian centers. Regular environmental monitoring is a good practice to maintain contamination as low as reasonably achievable.

Evaluation of the environmental dose commitment due to radium-contaminated soil

International Nuclear Information System (INIS)

Feldman, J.; Eng, J.; Giardina, P.A.

1979-01-01

The Middlesex Sampling Plant located in Middlesex, NJ was a uranium ore sampling plant operating during the 1940s and 1950s. A radiological problem was identified during a routine program to resurvey selected former MED/AEC sites which are no longer under government control. The survey, when conducted by the US Department of Energy (DOE), indicated that the Middlesex facility had a radium and radon problem on-site as well as off-site, where some of the contaminated soil was used as landfill. The old sampling plant is presently being used as a Marine Corps Reserve Training Center. Subsequent, more detailed studies have identified possible solutions to the contamination problem. The US Environmental Protection Agency (EPA) is examining cleanup options based on a cost/benefit analysis utilizing the environmental dose commitment concept rather than an annual dose calculation. The practice of using dose to local populations as a basis for impact assessment can lead to a large underestimate of the total potential impact from the continuous environmental release of radon

Multifactorial effects of ambient temperature, precipitation, farm management, and environmental factors determine the level of generic Escherichia coli contamination on preharvested spinach.

Science.gov (United States)

Park, Sangshin; Navratil, Sarah; Gregory, Ashley; Bauer, Arin; Srinath, Indumathi; Szonyi, Barbara; Nightingale, Kendra; Anciso, Juan; Jun, Mikyoung; Han, Daikwon; Lawhon, Sara; Ivanek, Renata

2015-04-01

A repeated cross-sectional study was conducted to identify farm management, environment, weather, and landscape factors that predict the count of generic Escherichia coli on spinach at the preharvest level. E. coli was enumerated for 955 spinach samples collected on 12 farms in Texas and Colorado between 2010 and 2012. Farm management and environmental characteristics were surveyed using a questionnaire. Weather and landscape data were obtained from National Resources Information databases. A two-part mixed-effect negative binomial hurdle model, consisting of a logistic and zero-truncated negative binomial part with farm and date as random effects, was used to identify factors affecting E. coli counts on spinach. Results indicated that the odds of a contamination event (non-zero versus zero counts) vary by state (odds ratio [OR] = 108.1). Odds of contamination decreased with implementation of hygiene practices (OR = 0.06) and increased with an increasing average precipitation amount (mm) in the past 29 days (OR = 3.5) and the application of manure (OR = 52.2). On contaminated spinach, E. coli counts increased with the average precipitation amount over the past 29 days. The relationship between E. coli count and the average maximum daily temperature over the 9 days prior to sampling followed a quadratic function with the highest bacterial count at around 24°C. These findings indicate that the odds of a contamination event in spinach are determined by farm management, environment, and weather factors. However, once the contamination event has occurred, the count of E. coli on spinach is determined by weather only. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Effects of decontamination at varying contamination levels of Campylobacter jejuni on broiler meat

DEFF Research Database (Denmark)

Boysen, Louise; Wechter, Naja Strandby; Rosenquist, Hanne

2013-01-01

/sample) or single or few strains of the species (or both) should not be interpreted as a generic result for the species. If inoculation studies cannot be replaced by investigations of naturally contaminated meat, we advise using a mixture of strains found in the production environment at levels as close as possible...... to the natural contamination level....

Environmental contamination and human exposure to manganese--contribution of methylcyclopentadienyl manganese tricarbonyl in unleaded gasoline.

Science.gov (United States)

Zayed, J; Vyskocil, A; Kennedy, G

1999-01-01

The organomanganese compound MMT (methylcyclopentadienyl manganese tricarbonyl), an antiknock additive in unleaded gasoline, has been used in Canada since 1976. Indeed, Canada is the only country where MMT is almost exclusively used. In October 1995, by court decision the Environmental protection Agency (EPA) granted Ethyl's waiver for the use of MMT in the United States. Paradoxically, in 1997 the federal government of Canada adopted a law (C-29) that banned both the interprovincial trade and the importation for commercial purposes of manganese-based substances, including MMT. However, MMT is currently widely used in Canada because of substantial stockpiling, and six Canadian provinces are challenging the law in the courts. Moreover, MMT has been approved for use in Argentina, Australia, Bulgaria, Russia, and conditionally, in New Zealand. It has been suggested by some scientists that combustion of MMT may be a significant source of exposure to inorganic Mn in urban areas. The crucial question is whether Mn contamination from industrial sources combined with the additional contamination that would result from the widespread use of MMT would lead to toxic effects. Our research efforts have attempted to assess the environmental/ecosystem Mn contamination arising from the combustion of MMT in abiotic and biotic systems as well as human exposure. The experimental evidence acquired so far provides useful information on certain environmental consequences of the use of MMT as well as raising a number of questions. Our results gave evidence indicating that roadside air, soils, plants, and animals may be contaminated by Mn. As well, some specific groups of the population could have a higher level of exposure to Mn. Nevertheless, the levels of exposure remain below international guide values. Further studies and further characterization of dose-response relationships are thus needed to provide successful implementation of evidence-based risk-assessment approaches.

Genotoxic effects induced by the exposure to an environmental mixture of illicit drugs to the zebra mussel.

Science.gov (United States)

Parolini, Marco; Magni, Stefano; Castiglioni, Sara; Binelli, Andrea

2016-10-01

Despite the growing interest on the presence of illicit drugs in freshwater ecosystems, just recently the attention has been focused on their potential toxicity towards non-target aquatic species. However, these studies largely neglected the effects induced by exposure to complex mixtures of illicit drugs, which could be different compared to those caused by single psychoactive molecules. This study was aimed at investigating the genetic damage induced by a 14-day exposure to a realistic mixture of the most common illicit drugs found in surface waters worldwide (cocaine, benzoylecgonine, amphetamine, morphine and 3,4-methylenedioxymethamphetamine) on the zebra mussel (Dreissena polymorpha). The mixture caused a significant increase of DNA fragmentation and triggered the apoptotic process and micronuclei formation in zebra mussel hemocytes, pointing out its potential genotoxicity towards this bivalve species. Copyright © 2016 Elsevier Inc. All rights reserved.

Epidemiology of Chronic Wasting Disease: PrPres Detection, Shedding and Environmental Contamination

National Research Council Canada - National Science Library

Lewis, Randolph V

2005-01-01

...) from orally infected mule and white-tailed deer and elk. Finally these techniques will be applied to investigating the nature of environmental contamination that may be associated with CND transmission...

Aging effects on oil-contaminated Kuwaiti sand

International Nuclear Information System (INIS)

Al-Sanad, H.A.; Ismael, N.F.

1997-01-01

Large quantities of oil-contaminated sands resulted from the destruction of oil wells and the formation of oil lakes in Kuwait at the end of the Gulf Wa/r. A laboratory testing program was carried out to determine the geotechnical properties of this material and the effect of aging on their properties. Tests included direct shear, triaxial, and consolidation tests on clean and contaminated sand at the same relative density. The influence of aging was examined by testing uncontaminated sand after aging for one, three, and six months in natural environmental conditions. The results indicated increased strength and stiffness due to aging and a reduction of the oil content due to evaporation of volatile compounds. The factors that influence the depth of oil penetration in compacted sand columns were also examined including the type of oil, relative density, and the amount of fines

Insights into aquatic toxicities of the antibiotics oxytetracycline and ciprofloxacin in the presence of metal: Complexation versus mixture

Energy Technology Data Exchange (ETDEWEB)

Yu, Zhang [Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Cai Xiyun, E-mail: xiyuncai@dlut.edu.cn [Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Xianming, Lang [Liaoning Academy of Environmental Sciences, Shenyang 110031 (China); Xianliang, Qiao; Xuehua, Li; Jingwen, Chen [Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China)

2012-07-15

Co-contamination of ligand-like antibiotics (e.g., tetracyclines and quinolones) and heavy metals prevails in the environment, and thus the complexation between them is involved in environmental risks of antibiotics. To understand toxicological significance of the complex, effects of metal coordination on antibiotics' toxicity were investigated. The complexation of two antibiotics, oxytetracycline and ciprofloxacin, with three heavy metals, copper, zinc, and cadmium, was verified by spectroscopic techniques. The antibiotics bound metals via multiple coordination sites and rendered a mixture of various complexation speciations. Toxicity analysis indicated that metal coordination did modify the toxicity of the antibiotics and that antibiotic, metal, and their complex acted primarily as concentration addition. Comparison of EC{sub 50} values revealed that the complex commonly was highest toxic and predominately correlated in toxicity to the mixture. Finally, environmental scenario analysis demonstrated that ignoring complexation would improperly classify environmental risks of the antibiotics. - Highlights: Black-Right-Pointing-Pointer The complex of antibiotic with metal is a mixture of various complexation modes. Black-Right-Pointing-Pointer Antibiotic and metal act as various combined interactions when their complexation is ignored. Black-Right-Pointing-Pointer Antibiotic, metal, and their complex act as concentration addition interaction. Black-Right-Pointing-Pointer Complex commonly is the highest toxicant. Black-Right-Pointing-Pointer Neglecting complexation renders improper classification of risks for antibiotics. - Antibiotic, heavy metal and their complex act primarily as concentration addition interaction and the complex commonly is highest toxic.

Food Adulteration and Bio-magnification of Environmental Contaminants: A Comprehensive Risk Framework for Bangladesh

Directory of Open Access Journals (Sweden)

Nehreen eMajed

2016-05-01

Full Text Available This article thoroughly investigates the severity of the prevailing environmental conditions and evaluates the resulting threats to food intake and public health in Bangladesh by establishing relationship among different contaminant transfer mechanisms to human. It describes the potential of certain contaminants to get bio-magnified through the food chain. A database was prepared on a number of contaminants in the study area that are responsible for rendering different foods vulnerable to produce long term or short-term health effects. Contaminants that have been identified in the food sources were categorized in a continuum based on their allowable daily intake. A protocol has been developed which will enable the assessment of the potential of a contaminant to bio-magnify through food chain to understand the contribution of a contaminant on different levels of food chain. The study also provides a detailed assessment of the public health risks associated with direct ingestion of adulterated foods and intake of contaminants through food chain or water intake. Their intake to human body was quantified, which provides an indication of the toxicity level of the contaminants and possible impact on human health. The traditional four steps of risk assessment technique have been employed for some model contaminants (including metals, organic contaminants and food adulterants. Additionally, existing rules and regulations of Bangladesh were identified with possible limitations that can play significant role in controlling the food adulteration practices and concentration of contaminants in the environment and human body. Finally, a holistic approach to necessary interventions has been prescribed at policy, treatment and evaluation level to prevent the water pollution and food adulteration. Thus, a much-needed comprehensive framework is prescribed in this study to promote safety in food handling, preserve environment and improve health-based strategies in

Italian multicentre study on microbial environmental contamination in dental clinics: a pilot study.

Science.gov (United States)

Pasquarella, Cesira; Veronesi, Licia; Castiglia, Paolo; Liguori, Giorgio; Montagna, Maria Teresa; Napoli, Christian; Rizzetto, Rolando; Torre, Ida; Masia, Maria Dolores; Di Onofrio, Valeria; Colucci, Maria Eugenia; Tinteri, Carola; Tanzi, Marialuisa

2010-09-01

The dental practice is associated with a high risk of infections, both for patients and healthcare operators, and the environment may play an important role in the transmission of infectious diseases. A microbiological environmental investigation was carried out in six dental clinics as a pilot study for a larger multicentre study that will be performed by the Italian SItI (Society of Hygiene, Preventive Medicine and Public Health) working group "Hygiene in Dentistry". Microbial contamination of water, air and surfaces was assessed in each clinic during the five working days of the week, before and during treatments. Air and surfaces were also examined at the end of the daily activity. A wide variation was found in microbial environmental contamination, both within the participating clinics and relative to the different sampling times. Microbial water contamination in Dental Unit Water Systems (DUWS) reached values of up to 26x10(4)cfu/mL (colony forming units per millilitre). P. aeruginosa was found in 33% of the sampled DUWS and Legionella spp. in 50%. A significant decrease in the Total Viable Count (TVC) was recorded during the activity. Microbial air contamination showed the highest levels during dental treatments and tended to decrease at the end of the working activity (p<0.05). Microbial buildup on surfaces increased significantly during the working hours. As these findings point out, research on microbial environmental contamination and the related risk factors in dental clinics should be expanded and should also be based on larger collections of data, in order to provide the essential knowledge aimed at targeted preventive interventions. Copyright 2010 Elsevier B.V. All rights reserved.

Metal and pharmaceutical mixtures: Is ion loss the mechanism underlying acute toxicity and widespread additive toxicity in zebrafish?

Energy Technology Data Exchange (ETDEWEB)

Alsop, Derek, E-mail: alsopde@mcmaster.ca; Wood, Chris M.

2013-09-15

Highlights: •Zebrafish larvae were used to test the acute toxicity of contaminant mixtures. •Interactions were observed between metals, ammonia and pharmaceuticals. •Larval Na{sup +} loss was observed with exposure to all acutely toxic contaminants tested. •Water quality criteria should recognize the toxic interactions between contaminants. -- Abstract: The acute toxicities and mechanisms of action of a variety of environmental contaminants were examined using zebrafish larvae (Danio rerio; 4–8 days post fertilization). Toxic interactions were observed between metals. For example, the addition of a sublethal level of nickel (15% of the LC{sub 50}, one third of the LC{sub 01}) to all copper treatments decreased the copper 96 h LC{sub 50} by 58%, while sublethal copper exposure (6% of the copper LC{sub 50}, 13% of the LC{sub 01}) decreased the cadmium 96 h LC{sub 50} by 47%. Two predictive models were assessed, the concentration addition (CA) model, which assumes similar mechanisms of action, and the independent action (IA) model, which assumes different mechanisms of action. Quantitative comparisons indicated the CA model performed better than the IA model; the latter tended to underestimate combined toxicity to a greater extent. The effects of mixtures with nickel or ammonia were typically additive, while mixtures with copper or cadmium were typically greater than additive. Larvae exposed to cadmium, copper or nickel experienced whole body ion loss. Decreases were greatest for Na{sup +} followed by K{sup +} (as high as 19% and 9%, respectively, in 24 h). Additive toxicity between copper and other pharmaceutical compounds such as fluoxetine (Prozac™), β-naphthoflavone, estrogen and 17α-ethinylestradiol were also observed. Similar to metals, acutely toxic concentrations of fluoxetine, β-naphthoflavone and ammonia all decreased whole body Na{sup +} and K{sup +}. Overall, whole body Na{sup +} loss showed the greatest correlation with mortality across a

Metal and pharmaceutical mixtures: Is ion loss the mechanism underlying acute toxicity and widespread additive toxicity in zebrafish?

International Nuclear Information System (INIS)

Alsop, Derek; Wood, Chris M.

2013-01-01

Highlights: •Zebrafish larvae were used to test the acute toxicity of contaminant mixtures. •Interactions were observed between metals, ammonia and pharmaceuticals. •Larval Na + loss was observed with exposure to all acutely toxic contaminants tested. •Water quality criteria should recognize the toxic interactions between contaminants. -- Abstract: The acute toxicities and mechanisms of action of a variety of environmental contaminants were examined using zebrafish larvae (Danio rerio; 4–8 days post fertilization). Toxic interactions were observed between metals. For example, the addition of a sublethal level of nickel (15% of the LC 50 , one third of the LC 01 ) to all copper treatments decreased the copper 96 h LC 50 by 58%, while sublethal copper exposure (6% of the copper LC 50 , 13% of the LC 01 ) decreased the cadmium 96 h LC 50 by 47%. Two predictive models were assessed, the concentration addition (CA) model, which assumes similar mechanisms of action, and the independent action (IA) model, which assumes different mechanisms of action. Quantitative comparisons indicated the CA model performed better than the IA model; the latter tended to underestimate combined toxicity to a greater extent. The effects of mixtures with nickel or ammonia were typically additive, while mixtures with copper or cadmium were typically greater than additive. Larvae exposed to cadmium, copper or nickel experienced whole body ion loss. Decreases were greatest for Na + followed by K + (as high as 19% and 9%, respectively, in 24 h). Additive toxicity between copper and other pharmaceutical compounds such as fluoxetine (Prozac™), β-naphthoflavone, estrogen and 17α-ethinylestradiol were also observed. Similar to metals, acutely toxic concentrations of fluoxetine, β-naphthoflavone and ammonia all decreased whole body Na + and K + . Overall, whole body Na + loss showed the greatest correlation with mortality across a variety of toxicants. We theorize that a disruption of

Contaminants at DOE sites and their susceptibility to bioremediation

International Nuclear Information System (INIS)

Lenhard, R.J.; Skeen, R.S.; Brouns, T.M.

1993-11-01

Contaminants at DOE sites encompass a range of common industrial pollutants. However, the prevalence of contaminant mixtures including organics, metals, and radionuclides is relatively unique to DOE's facilities. Bioremediation has been shown to be effective for destruction of many of the organic pollutants. The technology also has promise for application to many of the metals and radionuclides; however, field demonstrations for these applications have not yet been attempted. Because of the complexity of biodegradation of even a single-compound class, little has been done to develop or demonstrate in situ bioremediation technologies for multicompound combinations. The current bioremediation demonstration on CCl 4 and nitrates within the VOC-Arid Integrated Demonstration is one the first efforts to address inorganic and organic co-contaminants simultaneously. Additional research, technology development, and field demonstrations are needed to evaluate the applicability of in situ bioremediation to DOE's most common contaminant mixtures

Ruditapes philippinarum and Ruditapes decussatus under Hg environmental contamination.

Science.gov (United States)

Velez, Cátia; Galvão, Petrus; Longo, Renan; Malm, Olaf; Soares, Amadeu M V M; Figueira, Etelvina; Freitas, Rosa

2015-08-01

The native species Ruditapes decussatus and the invasive species Ruditapes philippinarum have an important ecological role and socio-economic value, from the Atlantic and Mediterranean to the Indo-Pacific region. In the aquatic environment, they are subjected to the presence of different contaminants, such as mercury (Hg) and its methylated form, methylmercury (MeHg). However, few studies have assessed the impacts of Hg on bivalves under environmental conditions, and little is known on bivalve oxidative stress patterns due to Hg contamination. Therefore, this study aims to assess the Hg contamination in sediments as well as the concentration of Hg and MeHg in R. decussatus and R. philippinarum, and to identify the detoxification strategies of both species living in sympatry, in an aquatic system with historical Hg contamination. The risk to human health due to the consumption of clams was also evaluated. The results obtained demonstrated that total Hg concentration found in sediments from the most contaminated area was higher than the maximum levels established by Sediment Quality Guidelines. This study further revealed that the total Hg and MeHg accumulation in both species was strongly correlated with the total Hg contamination of the sediments. Nonetheless, the THg concentration in both species was lower than maximum permissible limits (MPLs) of THg defined by international organizations. R. decussatus and R. philippinarum showed an increase in lipid peroxidation levels along with the increase of THg accumulation by clams. Nevertheless, for both species, no clear trend was obtained regarding the activity of antioxidant (superoxide dismutase, catalase) and biotransformation (glutathione S-transferase) enzymes and metallothioneins with the increase of THg in clams. Overall, the present work demonstrated that both species can be used as sentinel species of contamination and that the consumption of these clams does not constitute a risk for human health.

Effects of a mixture of non-ortho- and mono-ortho-polychlorinated biphenyls on reproduction in Fundulus heteroclitus (Linnaeus)

Energy Technology Data Exchange (ETDEWEB)

Black, D.E.; Gutjahr-Gobell, R.; Pruell, R.J.; Bergen, B. [Environmental Protection Agency, Narragansett, RI (United States); McElroy, A.E. [State Univ. of New York, Stony Brook, NY (United States). Marine Sciences Research Center

1998-07-01

To assess the effects of polychlorinated biphenyls (PCBs) on reproduction, female Fundulus heteroclitus were exposed to a mixture of non-ortho- and mono-ortho-PCBs, mimicking the mixture found in fish collected from New Bedford Harbor, Massachusetts, USA, a PCB-contaminated estuary. Exposure was by intraperitoneal injection of the mixture dissolved in corn oil. Doses of 0.76, 3.8, and 19 {micro}g PCB mixture per gram of wet weight produced liver concentrations of 2.99, 12.2, and 32.8 {micro}g non-ortho- and mono-ortho-PCBs per gram of dry liver, with dioxin toxic equivalency concentrations (TEQs) of 0.0963, 0.409, and 0.720 ng/g, respectively. Female mortality was 58%, and egg production was reduced by 77% at the highest dose, compared to controls. Food consumption declined with increasing PCB concentration, suggesting that PCBs act indirectly to reduce fecundity through an energetic effect. Pituitary gonadotropin content appeared to be suppressed at the highest dose, but the ability of ovarian follicles to produce estradiol and testosterone in vitro was not impaired. Significant residue-effects linkages were found, with TEQ emerging as a potential indicator of adverse effects. Mortality was directly related, and egg production was inversely related to log{sub 10}TEQ. Multiple regression analysis indicated that egg production was directly related to pituitary gonadotropin content and food consumption.

Single and combined effects of microplastics and mercury on juveniles of the European seabass (Dicentrarchus labrax): Changes in behavioural responses and reduction of swimming velocity and resistance time.

Science.gov (United States)

Barboza, Luís Gabriel Antão; Vieira, Luís Russo; Guilhermino, Lúcia

2018-05-01

Microplastics and mercury are environmental pollutants of great concern. The main goal of the present study was to investigate the effects of these pollutants, both individually and in binary mixtures, on the swimming performance of juvenile European seabass, Dicentrarchus labrax. Microplastics alone, mercury alone and all the mixtures caused significant reduction of the swimming velocity and resistance time of fish. Moreover, changes in behavioural responses including lethargic and erratic swimming behaviour were observed. These results highlight that fish behavioural responses can be used as sensitive endpoint to establish the effects of contamination by microplastics and also emphasizes the need to assess the combined effects of microplastics and other environmental contaminants, with special attention to the effects on behavioural responses in fish and other aquatic species. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Conditions for effective removal of pyrene from an artificially contaminated soil using Pseudomonas aeruginosa 57SJ rhamnolipids

Energy Technology Data Exchange (ETDEWEB)

Bordas, Francois [Institut national de la recherche scientifique, Centre INRS-Eau-Terre-Environnement, Universite du Quebec, 2800 rue Einstein, C.P. 7500, Sainte-Foy, Quebec, G1V 4C7 (Canada)]. E-mail: francois.bordas@unilim.fr; Lafrance, Pierre [Institut national de la recherche scientifique, Centre Eau, Terre et Environnement, Universite du Quebec, 490, rue de la Couronne, Quebec, G1K 9A9 (Canada)]. E-mail: pierre_lafrance@inrs-ete.uquebec.ca; Villemur, Richard [Institut national de la recherche scientifique, Centre INRS-Institut Armand Frappier, Universite du Quebec, 531 bd des Prairies, Laval, Quebec, H7V 1B7 (Canada)]. E-mail: richard.villemur@inrs-iaf.uquebec.ca

2005-11-15

The efficacy of a new rhamnolipid biosurfactants mixture to enhance the removal of pyrene from a soil artificially contaminated was investigated. The molar solubilization ratio (MSR) and the partition coefficient between the micelles and water (log K {sub m}) were found to be 7.5 x 10{sup -3} and 5.7, respectively. From soil column studies, the pyrene removal increased linearly with the concentration of the injected biosurfactants solution above the effective critical micellar concentration (0.4 g L{sup -1}). Flushing with a 5.0 g L{sup -1} biosurfactants solution increased the pyrene concentration in the effluent by 178 times. At high biosurfactants' concentrations (2.5 and 5.0 g L{sup -1}), the cumulative pyrene recovery reached 70%. This pyrene remobilization takes place independently of the soil organic carbon solubilization. This study provides a combination of batch and column experiments in order to find the conditions for effective soil remediation using a new rhamnolipids mixture. - The potential of newly isolated biosurfactants to mobilize PAHs from contaminated soils was evaluated from the determination in dynamic conditions of their effective critical micellar concentration.

Prenatal exposure to environmental chemical contaminants and asthma and eczema in school-age children

DEFF Research Database (Denmark)

Smit, Lidwien A M; Lenters, Virissa; Høyer, Birgit Bjerre

2015-01-01

BACKGROUND: Emerging evidence suggests that prenatal or early-life exposures to environmental contaminants may contribute to an increased risk of asthma and allergies in children. We aimed to the explore associations of prenatal exposures to a large set of environmental chemical contaminants...... asthma, eczema, and wheeze. We applied principal components analysis (PCA) to sixteen contaminants in maternal serum sampled during pregnancy, including perfluoroalkyl substances (PFASs), metabolites of diethylhexyl (DEHP) and diisononyl (DiNP) phthalates, PCB-153, and p,p'-DDE. Scores of five principal...... components (PCs) explaining 70% of the variance were included in multiple logistic regression models. RESULTS: In a meta-analysis that included both populations, the PC2 score, reflecting exposure to DiNP, was negatively associated with current eczema (OR 0.71, 95% CI 0.52-0.96). Other associations were...

Biomarker responses to environmental contamination in estuaries: A comparative multi-taxa approach.

Science.gov (United States)

Duarte, Irina A; Reis-Santos, Patrick; França, Susana; Cabral, Henrique; Fonseca, Vanessa F

2017-08-01

Estuaries are highly productive ecosystems subjected to numerous anthropogenic pressures with consequent environmental quality degradation. In this study, multiple biomarker responses [superoxide dismutase (SOD), catalase (CAT), ethoxyresorufin O-deethylase (EROD) and glutathione S-transferase (GST) activities, as well as lipid peroxidation (LPO) and DNA damage (DNAd)] were determined in two fish (Dicentrarchus labrax and Pomatoschistus microps) and four macroinvertebrate species (Carcinus maenas, Crangon crangon, Hediste diversicolor and Scrobicularia plana) from the Ria de Aveiro and Tejo estuaries over distinct months. Two sites per estuarine system were selected based on anthropogenic pressures and magnitude of environmental contamination. Antioxidant enzyme activities in fish species suggested a ubiquitous response to oxidative stress, while biotransformation and effect biomarkers exhibited higher spatial and temporal variation. In invertebrate species, biotransformation enzyme activity was clearly less variable than in fish evidencing lower xenobiotic transformation capability. Overall, largest biomarker responses were found in the most contaminated sites (Tejo), yet species-specific patterns were evident. These should be factored in multi-taxa approaches, considering that the differential functional traits of species, such as habitat use, life-stage, feeding or physiology can influence exposure routes and biomarker responses. The Integrated Biomarker Response index highlighted patterns in biomarker responses which were not immediately evident when analyzing biomarkers individually. Overall, results provided insights into the complexity of species responses to contamination in naturally varying estuarine environments. Ultimately, multi-taxa and multi-biomarker approaches provide a comprehensive and complementary view of ecosystem health, encompassing diverse forms of biological integration and exposure routes, and allow the validation of results among markers

Multimedia contaminant environmental exposure assessment methodology as applied to Los Alamos, New Mexico

International Nuclear Information System (INIS)

Whelan, G.; Thompson, F.L.; Yabusaki, S.B.

1983-02-01

The MCEA (Multimedia Contaminant Environmental Exposure Assessment) methodology assesses exposures to air, water, soil, and plants from contaminants released into the environment by simulating dominant mechanisms of contaminant migration and fate. The methodology encompasses five different pathways (i.e., atmospheric, terrestrial, overland, subsurface, and surface water) and combines them into a highly flexible tool. The flexibility of the MCEA methodology is demonstrated by encompassing two of the pathways (i.e., overland and surface water) into an effective tool for simulating the migration and fate of radionuclides released into the Los Alamos, New Mexico region. The study revealed that: (a) the 239 Pu inventory in lower Los Alamos Canyon increased by approximately 1.1 times for the 50-y flood event; (b) the average contaminant 239 Pu concentrations (i.e., weighted according to the depth of the respective bed layer) in lower Los Alamos Canyon for the 50-y flood event decreased by 5.4%; (c) approx. 27% of the total 239 Pu contamination resuspended from the entire bed (based on the assumed cross sections) for the 50-y flood event originated from lower Pueblo Canyon; (d) an increase in the 239 Pu contamination of the bed followed the general deposition patterns experienced by the sediment in Pueblo-lower Los Alamos Canyon; likewise, a decrease in the 239 Pu contamination of the bed followed general sediment resuspension patterns in the canyon; (e) 55% of the 239 Pu reaching the San Ildefonso Pueblo in lower Los Alamos Canyon originated from lower Los Alamos Canyon; and (f) 56% of the 239 Pu contamination reaching the San Ildefonso Pueblo in lower Los Alamos Canyon was carried through towards the Rio Grande. 47 references, 41 figures, 29 tables

Tactic-operational problems of soldiers, civilians and environmental protection against contamination

International Nuclear Information System (INIS)

Krauze, M.

1994-01-01

The military problems connected with the probable use in warfare the chemical and nuclear weapon have been discussed. The concept of soldiers, civilians and environmental protection against the chemical and radiological contamination has been presented from the view point of military tactics

Nutrients versus emerging contaminants–Or a dynamic match between subsidy and stress effects on stream biofilms

International Nuclear Information System (INIS)

Aristi, I.; Casellas, M.; Elosegi, A.; Insa, S.; Petrovic, M.; Sabater, S.; Acuña, V.

2016-01-01

Freshwater ecosystems are threatened by multiple anthropogenic stressors, which might be differentiated into two types: those that reduce biological activity at all concentrations (toxic contaminants), and those that subsidize biological activity at low concentrations and reduce it at high concentrations (assimilable contaminants). When occurring in mixtures, these contaminants can have either antagonistic, neutral or synergistic effects; but little is known on their joint effects. We assessed the interaction effects of a mixture of assimilable and toxic contaminants on stream biofilms in a manipulative experiment using artificial streams, and following a factorial design with three nutrient levels (low, medium or high) and either presence or absence of a mixture of emerging contaminants (ciprofloxacin, erythromycin, diclofenac, methylparaben, and sulfamethoxazole). We measured biofilm biomass, basal fluorescence, gross primary production and community respiration. Our initial hypotheses were that biofilm biomass and activity would: increase with medium nutrient concentrations (subsidy effect), but decrease with high nutrient concentrations (stress effect) (i); decrease with emerging contaminants, with the minimum decrease at medium nutrient concentrations (antagonistic interaction between nutrients subsidy and stress by emerging contaminants) and the maximum decrease at high nutrient concentrations (synergistic interaction between nutrients and emerging contaminants stress) (ii). All the measured variables responded linearly to the available nutrients, with no toxic effect at high nutrient concentrations. Emerging contaminants only caused weak toxic effects in some of the measured variables, and only after 3–4 weeks of exposure. Therefore, only antagonistic interactions were observed between nutrients and emerging contaminants, as medium and high nutrient concentrations partly compensated the harmful effects of emerging contaminants during the first weeks of the

Is the use of low-pressure pulsatile lavage for pressure ulcer management associated with environmental contamination with Acinetobacter baumannii?

Science.gov (United States)

Ho, Chester H; Johnson, Tova; Miklacic, Joan; Donskey, Curtis J

2009-10-01

Ho CH, Johnson T, Miklacic J, Donskey CJ. Is the use of low-pressure pulsatile lavage for pressure ulcer management associated with environmental contamination with Acinetobacter baumannii? To determine the extent of environmental contamination associated with low-pressure pulsatile lavage of stage III or IV pressure ulcers in patients with spinal cord injury (SCI) when routine infection control precautions are used for wounds colonized or infected with Acinetobacter baumannii. Prospective investigation in which pressure ulcer cultures and environmental cultures were obtained before and after low-pressure pulsatile lavage treatment, and before and after regular dressing changes. Environmental cultures included the patient's bedrail and settle plates placed 0.6, 1.5, and 2.4m from the wound to assess airborne spread of A. baumannii. SCI inpatient unit in a Department of Veterans Affairs Medical Center. Inpatients (N=15) with SCI receiving daily low-pressure pulsatile lavage treatment for stage III or IV pressure ulcers with standard dressing change, as well as regular dressing changes without low-pressure pulsatile lavage at other times of the day. Standard, regular dressing changes and dressing changes with low-pressure pulsatile lavage. Comparison of frequency of environmental contamination with A. baumannii associated with low-pressure pulsatile lavage versus regular dressing changes. Of the 15 SCI inpatients meeting inclusion criteria, 9 (60%) grew A. baumannii from their wounds. Of the 9 patients with wound cultures positive for A. baumannii, only 1 (11%) had environmental contamination with this organism after performance of low-pressure pulsatile lavage, and the same patient had environmental contamination after a standard dressing change. The antibiotic susceptibility patterns of the wound and environmental A. baumannii isolates were identical. Low-pressure pulsatile lavage using the infection control methods described is not associated with an increased

Impaired immunity in harbour seals (Phoca vitulina) exposed to bioaccumulated environmental contaminants: review of a long-term feeding study.

NARCIS (Netherlands)

R.L. de Swart (Rik); P.S. Ross (Peter); J.G. Vos (Joseph); A.D.M.E. Osterhaus (Albert)

1996-01-01

textabstractMass mortalities among seals and dolphins inhabiting contaminated marine regions have led to speculation about a possible involvement of immunosuppression associated with environmental pollution. To evaluate whether contaminants at ambient environmental levels can affect immune function

Pollen contamination in seed mixture increases the dominance of resistance to Bt maize in Spodoptera frugiperda (Lepidoptera: Noctuidae).

Science.gov (United States)

Yang, Fei; Kerns, David L; Brown, Sebe; Head, Graham P; Huang, Fangneng

2017-11-01

Seed mixture, also called 'RIB', has been used to provide refuge populations for delaying insect resistance. Pollen contamination in RIB could result in refuge kernels of non-Bt maize expressing variable Bt proteins. Data are lacking regarding the impact of pollen contamination on evolution of resistance for ear-feeding insects. Here, we used Spodoptera frugiperda and Cry1F-maize as a model to examine if pollen contamination in RIB increases the dominance of insect resistance. Pollen contamination caused >66% refuge kernels in 5:95% (non-Bt:Bt) and 20:80% RIBs to express Cry1F protein. Survival at adult stage on pure non-Bt ears was similar (54.4-63.3%) among Cry1F-susceptible (SS), Cry1F-resistant (RR) and Cry1F-heterozygous (RS) S. frugiperda. On Bt ears, survival was similar between SS and RS (0.0-1.7%), but it was significantly less than that of RR (59.2%). On the two RIB refuge ears, survival at adult stage for RS (42.3% in 5:95% RIB; 50.0% in 20:80% RIB) was significantly higher than for SS (8.7% in 5:95% RIB; 10.0% in 20:80% RIB). The results suggest that pollen contamination in RIB could increase the dominance of resistance for ear-feeding insects by significantly reducing susceptible refuge populations and supporting higher survival of heterozygotes relative to homozygous susceptible insects. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Association of Environmental Contamination in the Home With the Risk for Recurrent Community-Associated, Methicillin-Resistant Staphylococcus aureus Infection.

Science.gov (United States)

Knox, Justin; Sullivan, Sean B; Urena, Julia; Miller, Maureen; Vavagiakis, Peter; Shi, Qiuhu; Uhlemann, Anne-Catrin; Lowy, Franklin D

2016-06-01

The role of environmental contamination in recurrent Staphylococcus aureus infections within households and its potential effect on intervention strategies has been debated recently. To assess whether household environmental contamination increases the risk for recurrent infection among individuals with a community-associated methicillin-resistant S aureus (MRSA) infection. This cohort study was conducted from November 1, 2011, to June 30, 2014, in the Columbia University Medical Center catchment area. All patients within 72 hours of presentation with skin or soft-tissue infections and blood, urine, or sputum cultures positive for MRSA were identified. Two hundred sixty-two patients met study inclusion criteria; 83 of these (31.7%) agreed to participate (index patients) with 214 household members. Participants were followed up for 6 months, and 62 of the 83 households (74.7%) completed follow-up. Participants and researchers were blinded to exposure status throughout the study. Follow-up was completed on June 30, 2014, and data were assessed from July 1, 2014, to February 19, 2016. Concordant environmental contamination, defined as having an isolate with the identical staphylococcal protein A and staphylococcal chromosomal cassette mec type or antibiogram type as the index patient's clinical isolate, present on 1 or more environmental surfaces at the time of a home visit to the index patient after infection. Index recurrent infection, defined as any self-reported infection among the index patients during follow-up. One patient did not complete any follow-up. Of the remaining 82 index patients, 53 (64.6%) were female and 59 (72.0%) were Hispanic. The mean age was 30 (SD, 20; range, 1-79) years. Forty-nine of 61 MRSA infections where the clinical isolate could be obtained (80.3%) were due to the epidemic strain USA300. Among the 82 households in which a patient had an index MRSA infection, the clinical isolate was present in the environment in 20 (24.4%) and not

Vermiremediation of soils contaminated with mixture of petroleum ...

African Journals Online (AJOL)

In this paper, vermiremediation, a biological technique was utilized in order to clean-up soil contaminated with gasoline, diesel and spent engine oil using an earthworm - Eisenia fetida. The contaminated soils were analyzed for the total petroleum hydrocarbon (TPH) level every 24 hours over a period of 120 hours using ...

Environmental policies, politics, and community risk perception: case study of community contamination in Casper, Wyoming.

Science.gov (United States)

Tajik, Mansoureh; Gottlieb, Karen; Lowndes, Nita; Stewart, Gloria

2007-01-01

We identify and explain factors that affected a community's perception of risk due to extensive industrial contamination and people's distrust of government agencies regarding the environmental investigations. Intrinsic bounded case study methodology was used to conduct research about extensive environmental contaminations due to activities of an oil refinery in North Casper, Wyoming, and the citizens' response. Data were collected from multiple sources that included public testimonies, observations, public hearings and meetings minutes, newspaper articles, archived records obtained from federal and state environmental and health agencies, as well as industry records obtained through Freedom of Information Act (FOIA) requests. The overarching theme that emerged was lack of trust due to several critical events and factors such as no response or delay in response time to community concerns, lack of transparency, perceived cover up, vague and fragmented communication by government and state officials, perception of pro-industry stance, and perceived unfair treatment. People's perception of environmental risks and their willingness to accept official explanations and outcomes of environmental investigations are strongly affected by their direct experiences with government agencies and the evidence of influence the powerful industries exert over relevant investigations. The government cannot successfully address public and community concerns about environmental health impacts of contaminations and in turn the public perception of risk unless it adopts and implements policies, procedures, and protocols that are clear, timely, transparent, and free from industry influence.

Chemical mixtures in untreated water from public-supply wells in the U.S. — Occurrence, composition, and potential toxicity

International Nuclear Information System (INIS)

Toccalino, Patricia L.; Norman, Julia E.; Scott, Jonathon C.

2012-01-01

Chemical mixtures are prevalent in groundwater used for public water supply, but little is known about their potential health effects. As part of a large-scale ambient groundwater study, we evaluated chemical mixtures across multiple chemical classes, and included more chemical contaminants than in previous studies of mixtures in public-supply wells. We (1) assessed the occurrence of chemical mixtures in untreated source-water samples from public-supply wells, (2) determined the composition of the most frequently occurring mixtures, and (3) characterized the potential toxicity of mixtures using a new screening approach. The U.S. Geological Survey collected one untreated water sample from each of 383 public wells distributed across 35 states, and analyzed the samples for as many as 91 chemical contaminants. Concentrations of mixture components were compared to individual human-health benchmarks; the potential toxicity of mixtures was characterized by addition of benchmark-normalized component concentrations. Most samples (84%) contained mixtures of two or more contaminants, each at concentrations greater than one-tenth of individual benchmarks. The chemical mixtures that most frequently occurred and had the greatest potential toxicity primarily were composed of trace elements (including arsenic, strontium, or uranium), radon, or nitrate. Herbicides, disinfection by-products, and solvents were the most common organic contaminants in mixtures. The sum of benchmark-normalized concentrations was greater than 1 for 58% of samples, suggesting that there could be potential for mixtures toxicity in more than half of the public-well samples. Our findings can be used to help set priorities for groundwater monitoring and suggest future research directions for drinking-water treatment studies and for toxicity assessments of chemical mixtures in water resources. - Highlights: ► We assessed mixtures in untreated groundwater samples from public-supply wells. ► A screening

A holistic passive integrative sampling approach for assessing the presence and potential impacts of waterborne environmental contaminants

Science.gov (United States)

Petty, J.D.; Huckins, J.N.; Alvarez, D.A.; Brumbaugh, W. G.; Cranor, W.L.; Gale, R.W.; Rastall, A.C.; Jones-Lepp, T. L.; Leiker, T.J.; Rostad, C. E.; Furlong, E.T.

2004-01-01

As an integral part of our continuing research in environmental quality assessment approaches, we have developed a variety of passive integrative sampling devices widely applicable for use in defining the presence and potential impacts of a broad array of contaminants. The semipermeable membrane device has gained widespread use for sampling hydrophobic chemicals from water and air, the polar organic chemical integrative sampler is applicable for sequestering waterborne hydrophilic organic chemicals, the stabilized liquid membrane device is used to integratively sample waterborne ionic metals, and the passive integrative mercury sampler is applicable for sampling vapor phase or dissolved neutral mercury species. This suite of integrative samplers forms the basis for a new passive sampling approach for assessing the presence and potential toxicological significance of a broad spectrum of environmental contaminants. In a proof-of-concept study, three of our four passive integrative samplers were used to assess the presence of a wide variety of contaminants in the waters of a constructed wetland, and to determine the effectiveness of the constructed wetland in removing contaminants. The wetland is used for final polishing of secondary-treatment municipal wastewater and the effluent is used as a source of water for a state wildlife area. Numerous contaminants, including organochlorine pesticides, polycyclic aromatic hydrocarbons, organophosphate pesticides, and pharmaceutical chemicals (e.g., ibuprofen, oxindole, etc.) were detected in the wastewater. Herein we summarize the results of the analysis of the field-deployed samplers and demonstrate the utility of this holistic approach.

Immunobiological effects of AFB1 and AFB1-FB1 mixture in experimental subchronic mycotoxicoses in rats

International Nuclear Information System (INIS)

Theumer, M.G.; Lopez, A.G.; Masih, D.T.; Chulze, S.N.; Rubinstein, H.R.

2003-01-01

Maize co-contamination with aflatoxin B1 (AFB1) and fumonisin B1 (FB1) is frequently found in several countries. Although the alterations on nutritional and immunologic parameters induced by these mycotoxins, when administered individually, are partially characterised, little is known about the effects induced in animals by a subchronic administration of both toxins mixtures. We have studied the nutritional and immunological alterations induced in rats fed during 90 days with a diet without mycotoxins, containing 40 ppb AFB1, and with a diet containing a mixture of 40 ppb AFB1 and 100 ppm FB1. Animals fed with the mixture of toxins obtained lower body weight than the control ones. The mitogenic response of spleen mononuclear cells (SMC) in vivo was higher in animals fed with AFB1. In in vitro studies, lower proliferations of SMC pre-exposed to AFB1 and to the mixture of toxins were detected. The SMC of animals fed with AFB1 produced lower levels of IL-2, higher of IL-4 and equal levels of IL-10. The SMC of animals fed with both toxins produced higher levels of IL-4, lower of IL-10 and equal levels of IL-2. The SMC preincubated with an AFB1-FB1 mixture produced higher concentrations of IL-4, lower of IL-10 and equal levels of IL-2. The peritoneal macrophages of animals that consumed AFB1 released less H 2 O 2 , while animals fed with the mixture of toxins produced higher levels. In in vitro studies, macrophages pre-exposed to the mixture of toxins released less H 2 O 2 . These results show different immunobiological effects produced by a mixture of mycotoxins in comparison to the individual action of the same toxins

Immunobiological effects of AFB1 and AFB1-FB1 mixture in experimental subchronic mycotoxicoses in rats

Energy Technology Data Exchange (ETDEWEB)

Theumer, M G; Lopez, A G; Masih, D T; Chulze, S N; Rubinstein, H R

2003-04-15

Maize co-contamination with aflatoxin B1 (AFB1) and fumonisin B1 (FB1) is frequently found in several countries. Although the alterations on nutritional and immunologic parameters induced by these mycotoxins, when administered individually, are partially characterised, little is known about the effects induced in animals by a subchronic administration of both toxins mixtures. We have studied the nutritional and immunological alterations induced in rats fed during 90 days with a diet without mycotoxins, containing 40 ppb AFB1, and with a diet containing a mixture of 40 ppb AFB1 and 100 ppm FB1. Animals fed with the mixture of toxins obtained lower body weight than the control ones. The mitogenic response of spleen mononuclear cells (SMC) in vivo was higher in animals fed with AFB1. In in vitro studies, lower proliferations of SMC pre-exposed to AFB1 and to the mixture of toxins were detected. The SMC of animals fed with AFB1 produced lower levels of IL-2, higher of IL-4 and equal levels of IL-10. The SMC of animals fed with both toxins produced higher levels of IL-4, lower of IL-10 and equal levels of IL-2. The SMC preincubated with an AFB1-FB1 mixture produced higher concentrations of IL-4, lower of IL-10 and equal levels of IL-2. The peritoneal macrophages of animals that consumed AFB1 released less H{sub 2}O{sub 2}, while animals fed with the mixture of toxins produced higher levels. In in vitro studies, macrophages pre-exposed to the mixture of toxins released less H{sub 2}O{sub 2}. These results show different immunobiological effects produced by a mixture of mycotoxins in comparison to the individual action of the same toxins.

Environmental analysis of endocrine disrupting effects from hydrocarbon contaminants in the ecosystem. 1997 annual progress report

International Nuclear Information System (INIS)

1997-01-01

'The overall objective of the basic research grant is to characterize the potential of common hydrocarbon contaminants in ecosystems to act as endocrine disruptors. The three major lines of research include (1) a biotechnology based screening system to identify potential hormone mimics and antagonists; (2) an animal screening system to identify biomarkers of endocrine effects. and (3) a literature review to identify compounds at a variety of DOE sites that need to be examined for endocrine disrupting effects. By relating results obtained from this research project to contamination problems at various DOE sites. CBR will provide data and information on endocrine disrupting contaminants to DOE for consideration in risk analyses for determining clean-up levels and priorities needed at the sites.'

A new mask to prevent environmental contamination during radio aerosol mouth-piece inhalation procedures

International Nuclear Information System (INIS)

Braga, Francisco Jose Hossri Nogueira.

1994-01-01

Environmental contamination is frequent during labelled aerosol mouth-piece inhalation procedures. Previous personnel data showed that in 18/18 situations air background activity has increased after inhalation and this may create serious routine and economical problems. We have tested a new adherent mask made of 3 M's TEGADERM in sixty 99 m Tc-DTPA inhalation studies and the results indicates that the use of such a mask may eliminate the problem of environmental contamination. The device is useful but not entirely efficient in cases when good skin adherence cannot be obtained. 48 refs, 10 figs, 2 tabs

Long-term Neurotoxic Effects of Early-life Exposure to Tetrachloroethylene-contaminated Drinking Water.

Science.gov (United States)

Aschengrau, Ann; Janulewicz, Patricia A; White, Roberta F; Vieira, Veronica M; Gallagher, Lisa G; Getz, Kelly D; Webster, Thomas F; Ozonoff, David M

2016-01-01

Tetrachloroethene (PCE) is a common environmental and occupational contaminant and an acknowledged neurotoxicant. From 1968 through 1983, widespread contamination of public drinking water supplies with PCE occurred in the Cape Cod region of Massachusetts. The source of the contamination was a vinyl liner applied to the inner surface of water distribution pipes. A retrospective cohort study (the Cape Cod Health Study) was undertaken to examine possible health consequences of early-life exposure to PCE-contaminated drinking water. This review describes the study methods and findings regarding the effects of prenatal and childhood exposure on neurologic outcomes during early adulthood, including vision, neuropsychological functioning, brain structure, risky behaviors, and mental illness. The review also describes the strengths and challenges of conducting population-based epidemiologic research in this unique setting. Participants were identified by cross-matching birth certificates and water system data. Information on health outcomes and confounding variables was collected from self-administered surveys (n = 1689), neuropsychological tests (n = 63), vision examinations (n = 63), and magnetic resonance imaging (n = 42). Early-life exposure to PCE was estimated using a leaching and transport model. The data analysis compared the occurrence of each health outcome among individuals with prenatal and early childhood PCE exposure to unexposed individuals while considering the effect of confounding variables. The study found evidence that early-life exposure to PCE-contaminated drinking water has long-term neurotoxic effects. The strongest associations were seen with illicit drug use, bipolar disorder, and post-traumatic stress disorder. Key strengths of the study were availability of historical data on affected water systems, a relatively high exposure prevalence and wide range of exposure levels, and little confounding. Challenges arose mainly from the historical

Regional risk assessment of environmental contamination from oil pipelines

International Nuclear Information System (INIS)

Pelmulder, S.D.; Eguchi, R.T.

1991-01-01

This paper presents a methodology for assessing the risk of environmental contamination from oil pipeline leaks due to earthquakes. Risk is measured both as volume of oil released and remediation cost. The methodology was developed for use on a regional scale and thus relies on a limited amount of input data. Monte Carlo techniques are used to simulate earthquake events, while a deterministic model is used to estimate the volume of oil released at a particular site. A library of cost models is used to estimate the contamination and resulting remediation cost based on the volume of oil released and the general site conditions. This methodology has been implemented in a computer program, OILOSS, and the results are presented as annual frequency of exceedence curves for volume of oil released and cost of remediation

Lead: Aspects of its ecology and environmental toxicity. [physiological effects of lead compound contamination of environment

Science.gov (United States)

Siegel, S. M.

1973-01-01

An analysis of lead toxicity in the Hawaiian environment was conducted. It was determined that lead enters the environment as an industrial contaminant resulting from the combustion of leaded gasoline. The amount of lead absorbed by the plants in various parts of the Hawaiian Islands is reported. The disposition of lead in the sediments of canals and yacht basins was investigated. The methods for conducting the surveys of lead content are described. Possible consequences of continued environmental pollution by burning leaded gasoline are discussed.

The effectiveness of electro-remediation of aged, metal-contaminated sediment in relation to sequential extraction of metals

NARCIS (Netherlands)

Merkx, O.K.; Loch, J.P.G.; Lima, A.T.; Dijk, J.A.; Kreuk, J.F. de; Kleingeld, P.J.

2013-01-01

Soil pollution is a universal environmental issue, and the clean-up of contaminated soils can be costly and time consuming. Traditional methods often do not provide an effective solution when it comes to fine-grained and highly impermeable soils and/or immobile contaminants. Electro-remediation,

Geostatistics and GIS: tools for characterizing environmental contamination.

Science.gov (United States)

Henshaw, Shannon L; Curriero, Frank C; Shields, Timothy M; Glass, Gregory E; Strickland, Paul T; Breysse, Patrick N

2004-08-01

Geostatistics is a set of statistical techniques used in the analysis of georeferenced data that can be applied to environmental contamination and remediation studies. In this study, the 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) contamination at a Superfund site in western Maryland is evaluated. Concern about the site and its future clean up has triggered interest within the community because residential development surrounds the area. Spatial statistical methods, of which geostatistics is a subset, are becoming increasingly popular, in part due to the availability of geographic information system (GIS) software in a variety of application packages. In this article, the joint use of ArcGIS software and the R statistical computing environment are demonstrated as an approach for comprehensive geostatistical analyses. The spatial regression method, kriging, is used to provide predictions of DDE levels at unsampled locations both within the site and the surrounding areas where residential development is ongoing.

Applicability of the Environmental Relative Moldiness Index for Quantification of Residential Mold Contamination in an Air Pollution Health Effects Study

Directory of Open Access Journals (Sweden)

Ali Kamal

2014-01-01

Full Text Available The Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS investigated the impact of exposure to traffic-related air pollution on the respiratory health of asthmatic children in Detroit, Michigan. Since indoor mold exposure may also contribute to asthma, floor dust samples were collected in participants homes (n=112 to assess mold contamination using the Environmental Relative Moldiness Index (ERMI. The repeatability of the ERMI over time, as well as ERMI differences between rooms and dust collection methods, was evaluated for insights into the application of the ERMI metric. ERMI values for the standard settled floor dust samples had a mean ± standard deviation of 14.5±7.9, indicating high levels of mold contamination. ERMI values for samples collected from the same home 1 to 7 months apart (n=52 were consistent and without systematic bias. ERMI values for separate bedroom and living room samples were highly correlated (r=0.69, n=66. Vacuum bag dust ERMI values were lower than for floor dust but correlated (r=0.58, n=28. These results support the use of the ERMI to evaluate residential mold exposure as a confounder in air pollution health effects studies.

Environmental contamination from a ground-level release of fission products

International Nuclear Information System (INIS)

Stupka, R.C.; Kephart, G.S.; Rittmann, P.D.

1986-08-01

On January 11, 1985, a ground-level release of fission products, primarily 90 Sr, occurred at the Hanford Site in southeastern Washington State. The release was detected during routine surveys and the majority of the contamination was confined to the immediate area where the release occurred. Response to the incident was complicated by a strong inversion that resulted in a buildup of 222 Rn daughter products on environmental air samples and outdoor surfaces. The cause of the release appears to have been the operation of a transfer jet that inadvertently pressurized an unblanked line leading to the 241-C-151 Diversion Box. A buildup of pressure inside the diversion box forced contaminated air through gaps in the diversion box cover blocks resulting in an unmonitored, short duration release to the environment. The source term was estimated using data obtained from environmental air samplers. The ground deposition speed was calculated using the integrated exposure (air samples) and surface contamination levels obtained from recently fallen snow. The total release was estimated to be 1.4 Ci 90 Sr and 0.02 Ci 137 Cs. Based on this source term, the maximum 50-yr dose commitment to onsite pesonnel was 50 mrem whole body and 600 mrem bone. No detectable internal deposition occurred during the incident and corrective action which followed; this was probably due to several factors: (1) prompt detection of the release; (2) localized contamination control; (3) excellent personnel protection practices; and (4) the protection offered by building ventilation systems. The theoretical maximum offsite individual would receive a potential 1-yr dose commitment of 0.01 mrem whole body and 0.2 mrem bone from this incident. The potential 50-yr dose commitment would be 0.13 mrem whole body and 2.0 mrem bone. In actuality, neither onsite or offsite individuals would be expected to receive even these small dose commitments

EFFECT OF FLY ASHES AND SEWAGE SLUDGE ON Fe, Mn, Al, Si AND Co UPTAKE BY GRASS MIXTURE

Directory of Open Access Journals (Sweden)

Jacek Antonkiewicz

2014-07-01

Full Text Available Application of sewage sludge for environmental management of fly ashes landfill site affects chemical composition of plants. The aim of the present investigations was learning the effect of growing doses of municipal sewage sludge on the yield and uptake of Fe, Mn, Al, Si and Co by grass mixture used for environmental management of fly ashes landfill. The experimental design comprised of 5 objects differing by a dose of municipal sewage sludge supplied per 1 hectare: I. control, II. 25 t d.m., III. 50 t d.m., IV. 75 t d.m. and V. 100 t d.m. Application of sewage sludge resulted in the increase in yield. The content of analyzed elements in the grass mixture depended significantly on sewage sludge dose. Increasing doses of sewage sludge caused marked increase in Mn and Co contents, while they decreased Fe, Al and Si contents in the grass mixture. It was found that growing doses of sewage sludge caused an improvement of Fe to Mn ratio value in the grass mixture. Assessing the element content in the grass mixture in the view of forage value, it was found that Fe and Mn content did not meet the optimal value. Si content in plants was below the optimal value.

The Matthew Effect and widely prescribed pharmaceuticals lacking environmental monitoring: case study of an exposure-assessment vulnerability.

Science.gov (United States)

Daughton, Christian G

2014-01-01

Assessing ambient exposure to chemical stressors often begins with time-consuming and costly monitoring studies to establish environmental occurrence. Both human and ecological toxicology are currently challenged by the unknowns surrounding low-dose exposure/effects, compounded by the reality that exposure undoubtedly involves mixtures of multiple stressors whose identities and levels can vary over time. Long absent from the assessment process, however, is whether the full scope of the identities of the stressors is sufficiently known. The Matthew Effect (a psychosocial phenomenon sometimes informally called the "bandwagon effect" or "iceberg effect," among others) may adversely bias or corrupt the exposure assessment process. The Matthew Effect is evidenced by decisions that base the selection of stressors to target in environmental monitoring surveys on whether they have been identified in prior studies, rather than considering the possibility that additional, but previously unreported, stressors might also play important roles in an exposure scenario. The possibility that the Matthew Effect might influence the scope of environmental stressor research is explored for the first time in a comprehensive case study that examines the preponderance of "absence of data" (in contrast to positive data and "data of absence") for the environmental occurrence of a very large class of potential chemical stressors associated with ubiquitous consumer use - active pharmaceutical ingredients (APIs). Comprehensive examination of the published data for an array of several hundred of the most frequently used drugs for whether their APIs are environmental contaminants provides a prototype example to catalyze discussion among the many disciplines involved with assessing risk. The findings could help guide the selection of those APIs that might merit targeting for environmental monitoring (based on the absence of data for environmental occurrence) as well as the prescribing of those

Environmental contamination with Toxocara spp. eggs in public parks and playground sandpits of Greater Lisbon, Portugal.

Science.gov (United States)

Otero, David; Alho, Ana M; Nijsse, Rolf; Roelfsema, Jeroen; Overgaauw, Paul; Madeira de Carvalho, Luís

Toxocarosis is a zoonotic parasitic disease transmitted from companion animals to humans. Environmental contamination with Toxocara eggs is considered to be the main source of human infections. In Portugal, knowledge regarding the current situation, including density, distribution and environmental contamination by Toxocara spp., is largely unknown. The present study investigated environmental contamination with Toxocara spp. eggs, in soil and faecal samples collected from public parks and playground sandpits in Greater Lisbon, Portugal. A total of 151 soil samples and 135 canine faecal samples were collected from 7 public sandpits and 12 public parks, over a 4 month-period. Soil samples were tested by a modified centrifugation and sedimentation/flotation technique and faecal samples were tested by an adaptation of the Cornell-Wisconsin method. Molecular analysis and sequencing were performed to discriminate Toxocara species in the soil. Overall, 85.7% of the sandpits (6/7) and 50.0% of the parks (6/12) were contaminated with Toxocara spp. eggs. The molecular analysis of soil samples showed that, 85.5% of the sandpits and 34.4% of the parks were contaminated with Toxocara cati eggs. Faecal analysis showed that 12.5% of the sandpits and 3.9% of the parks contained Toxocara canis eggs. In total, 53.0% of soil and 5.9% of faecal samples were positive for Toxocara spp. Additionally, 56.0% of the eggs recovered from the samples were embryonated after 60 days of incubation, therefore considered viable and infective. The average density was 4.2 eggs per hundred grams of soil. Public parks and playground sandpits in the Lisbon area were found to be heavily contaminated with T. cati eggs, representing a serious menace to public health as the studied areas represent common places where people of all ages, particularly children, recreate. This study sounds an alarm bell regarding the necessity to undertake effective measures such as reduction of stray animals, active faecal

Effects of petroleum and metal contaminated soil on plants and earthworms: Survival and bioaccumulation

International Nuclear Information System (INIS)

Tatem, H.E.; Simmers, J.W.; Skogerboe, J.G.; Lee, C.R.

1993-01-01

Earthworms, Eisenia foetida, and bermudagrass, Cynodon dactylon, were used in the laboratory to test the toxicity of contaminated sediment taken from a small fresh water lake in North Carolina. This work was part of an investigation to determine the potential effects of upland disposal of this sediment. The contaminated sediment contained As, Cr, Cu, Pb, Hg, Ni, Zn and petroleum hydrocarbons at concentrations much greater than nearby soils. Test cylinders were planted with bermudagrass; earthworms were added 30 days later. Both species were harvested at 60 days, weighed and submitted for chemical analyses. Cynodon was affected by the contaminated sediment but grew well in the mixtures of sediment and upland soil. Similar results were obtained with the Eisenia. These species did not accumulate hydrocarbons from the sediment with the possible exception of pyrene. The metals Cd, Pb, and Zn were elevated in plants exposed to the contaminated sediment. Earthworms exposed to this sediment accumulated Pb to concentrations greater than animals exposed to the manure control. This work demonstrated that a contaminated freshwater sediment was not toxic to plants or earthworms and that most petroleum hydrocarbons were not accumulated. The only metal that may be of some concern was Pb

Assessment of the Effectiveness of Environmental Dredging in South Lake, China

Science.gov (United States)

Wang, Xiao Yu; Feng, Jiang

2007-08-01

Environmental dredging is a primary remedial option for removal of the contaminated material from aquatic environment. Of primary concern in environmental dredging is the effectiveness of the intended sediment removal. A 5-year field monitoring study was conducted to assess the effectiveness of the environmental dredging in South Lake, China. The concentrations of total nitrogen (TN), total phosphors, and heavy metals (Zn, Pb, Cd, Cu, Cr, Ni, Hg, and As) before and after dredging in sediment were determined and compared. Multiple ecological risk indices were employed to assess the contamination of heavy metals before and after dredging. Our results showed that the total phosphorus levels reduced 42% after dredging. Similar changes for Hg, Zn, As Pb, Cd, Cu, Cr, and Ni were observed, with reduction percentages of 97.0, 93.1, 82.6, 63.9, 52.7, 50.1, 32.0, and 23.6, respectively, and the quality of sediment improved based on the criterion of Sediment Quality Guidelines by USEPA and contamination degree values (Cd) decreased significantly (paired t-test, p heavy metals from South Lake. Nevertheless, the dredging was ineffective to remove total nitrogen from sediment. We conclude that the reason for the observed increase in TN after dredging was likely ammonia release from the sediment impairing the dredging effectiveness.

Toxicological benchmarks for screening potential contaminants of concern for effects on terrestrial plants. Environmental Restoration Program

Energy Technology Data Exchange (ETDEWEB)

Suter, G.W. II; Will, M.E.; Evans, C.

1993-09-01

One of the initial stages in ecological risk assessment for hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration as ``contaminants of potential concern.`` This process is termed ``contaminant screening.`` It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 34 chemicals potentially associated with US Department of Energy (DOE) sites. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern. The purpose of this report is to present plant toxicity data and discuss their utility as benchmarks for determining the hazard to terrestrial plants caused by contaminants in soil. Benchmarks are provided for soils and solutions.

Environmental methicillin-resistant Staphylococcus aureus contamination in pig herds in relation to the productive phase and application of cleaning and disinfection.

Science.gov (United States)

Merialdi, G; Galletti, E; Guazzetti, S; Rosignoli, C; Alborali, G; Battisti, A; Franco, A; Bonilauri, P; Rugna, G; Martelli, P

2013-06-01

The aim of the study is to better understand MRSA environmental contamination in pig holdings in relation to the productive phase and the application of environmental cleaning and disinfection practices (C&D). This study was carried out on six herds. Dust samples from farrowing crates, weaning boxes, growing and finishing pens were collected from each herd environment prior to and after C&D and cultured for MRSA. Ten samples were collected at the end of each productive phase with the animals present and 10 additional samples were collected after C&D, prior to introduction of a new stock. The proportion of positive samples prior to C&D was lower in fattening than in other phases. The proportion of positive samples prior to and after C&D was 121/240 (50%) and 46/240 (19%) respectively. In the mixed effects logistic regression analysis it was shown not only that both productive phase and C&D were associated with the probability of having a positive sample but also that the C&D effect was different in the different productive phases. In particular the effect of C&D was stronger in farrowing crates than in the other productive phases. The results of this study show that, although current practices of cleaning and disinfection reduce MRSA environmental contamination, they are likely to be inadequate to the elimination of the microorganism. However, a strict application of hygienic protocols can lead to a marked reduction of MRSA environmental contamination. Copyright © 2012 Elsevier Ltd. All rights reserved.

Environmental magnetic methods for detecting and mapping contaminated sediments in lakes

Science.gov (United States)

Boyce, J. I.

2009-05-01

The remediation of contaminated sediments is an urgent environmental priority in the Great Lakes and requires detailed mapping of impacted sediment layer thickness, areal distribution and pollutant levels. Magnetic property measurements of sediment cores from two heavily polluted basins in Lake Ontario (Hamilton Harbour, Frenchman's Bay) show that concentrations of hydrocarbons (PAH) and a number of heavy metals (Pb, As, Ni, Cu, Cr, Zn, Cd, Fe) are strongly correlated with magnetic susceptibility. The magnetic susceptibility contrast between the contaminated sediment and underlying 'pre-colonial' sediments is sufficient to generate a total field anomaly (ca. 2-20 nT) that can be measured with a magnetometer towed above the lake bed. Systematic magnetic surveying (550 line km) of Hamilton Harbour using a towed marine magnetometer clearly identifies a number of well-defined magnetic anomalies that coincide with known accumulations of contaminated lake sediment. When calibrated against in-situ magnetic property measurements, the modeled apparent susceptibility from magnetic survey results can be used to classify the relative contaminant impact levels. The results demonstrate the potential of magnetic property measurements for rapid reconnaissance mapping of large areas of bottom contamination prior to detailed coring and sediment remediation.

Volatilization of multicomponent mixtures in soil vapor extraction applications

International Nuclear Information System (INIS)

Bass, D.H.

1995-01-01

In soil vapor extraction (SVE) applications involving multicomponent mixtures, prediction of mass removal by volatilization as a function remediation extent is required to estimate remediation time and to size offgas treatment equipment. SVE is a commonly used remediation technology which volatilizes and enhances aerobic biodegradation of contamination adsorbed to vadose zone soils. SVE is often applied at sites contaminated with petroleum products, which are usually mixtures of many different compounds with vapor pressures spanning several orders of magnitude. The most volatile components are removed first, so the vapor pressure of the remaining contaminant continually decreases over the course of the remediation. A method for assessing how vapor pressure, and hence the rate of volatilization, of a multicomponent mixture changes over the course of a vapor extraction remedy has been developed. Each component is listed, alone, with its mass fraction in the mixture, in decreasing order of pure component vapor pressure (where component analyses are unavailable, model compounds can be used), For most petroleum distillates, the vapor pressure for each component plotted against the cumulative mass fraction of the component in the mixture on semilog coordinates will produce a straight line with a high correlation coefficient. This regression can be integrated to produce an expression for vapor pressure of the overall mixture as a function of extent or remediation

RI Mapping System for Identification of Radiological Contamination in Environmental Water Supply System

Energy Technology Data Exchange (ETDEWEB)

Na, Teresa W.; Ha, Jang Ho; Kim, Han Soo; Lee, Seung Hyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Na, Teresa W.; Lee, Rena [Ewha Womans Univ., Hospital, Seoul (Korea, Republic of)

2012-03-15

The interest of radiation protection has risen due to accidents of the Nuclear Power Plant, nuclear terrorism, and the radiological contamination in the city, In this respect, the development of environmental radiation monitoring for the radiological contaminants has been studied. In this study, the experiment for the radiological contamination in the water supply pipe line system has been simulated and preliminarily tested. The CsI(Tl)-PIN diode detectors were used and the preliminary test of radiation monitoring system was performed as multi detection system. The 2D image reconstruction algorithm was also developed for feasibility of the constructed multi-detection system.

Environmental and body contamination from cleaning vomitus in a health care setting: A simulation study.

Science.gov (United States)

Phan, Linh; Su, Yu-Min; Weber, Rachel; Fritzen-Pedicini, Charissa; Edomwande, Osayuwamen; Jones, Rachael M

2018-04-01

Environmental service workers may be exposed to pathogens during the cleaning of pathogen-containing bodily fluids. Participants with experience cleaning hospital environments were asked to clean simulated, fluorescein-containing vomitus using normal practices in a simulated patient room. Fluorescein was visualized in the environment and on participants under black lights. Fluorescein was quantitatively measured on the floor, in the air, and on gloves and shoe covers. In all 21 trials involving 7 participants, fluorescein was found on the floor after cleaning and on participants' gloves. Lower levels of floor contamination were associated with the use of towels to remove bulk fluid (ρ = -0.56, P = .01). Glove contamination was not associated with the number or frequency of contacts with environmental surfaces, suggesting contamination occurs with specific events, such as picking up contaminated towels. Fluorescein contamination on shoe covers was measured in 19 trials. Fluorescein was not observed on participants' facial personal protective equipment, if worn, or faces. Contamination on other body parts, primarily the legs, was observed in 8 trials. Fluorescein was infrequently quantified in the air. Using towels to remove bulk fluid prior to mopping is part of the recommended cleaning protocol and should be used to minimize residual contamination. Contamination on shoes and the floor may serve as reservoirs for pathogens. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Chemical mixtures in untreated water from public-supply wells in the U.S. - Occurrence, composition, and potential toxicity

Energy Technology Data Exchange (ETDEWEB)

Toccalino, Patricia L., E-mail: ptocca@usgs.gov [U.S. Geological Survey (USGS), 6000 J Street, Placer Hall, Sacramento, California 95819 (United States); Norman, Julia E., E-mail: jnorman@usgs.gov [USGS, 2130 SW 5th Avenue, Portland, Oregon 97201 (United States); Scott, Jonathon C., E-mail: jon@usgs.gov [USGS, 202 NW 66th Street, Oklahoma City, Oklahoma 73116 (United States)

2012-08-01

Chemical mixtures are prevalent in groundwater used for public water supply, but little is known about their potential health effects. As part of a large-scale ambient groundwater study, we evaluated chemical mixtures across multiple chemical classes, and included more chemical contaminants than in previous studies of mixtures in public-supply wells. We (1) assessed the occurrence of chemical mixtures in untreated source-water samples from public-supply wells, (2) determined the composition of the most frequently occurring mixtures, and (3) characterized the potential toxicity of mixtures using a new screening approach. The U.S. Geological Survey collected one untreated water sample from each of 383 public wells distributed across 35 states, and analyzed the samples for as many as 91 chemical contaminants. Concentrations of mixture components were compared to individual human-health benchmarks; the potential toxicity of mixtures was characterized by addition of benchmark-normalized component concentrations. Most samples (84%) contained mixtures of two or more contaminants, each at concentrations greater than one-tenth of individual benchmarks. The chemical mixtures that most frequently occurred and had the greatest potential toxicity primarily were composed of trace elements (including arsenic, strontium, or uranium), radon, or nitrate. Herbicides, disinfection by-products, and solvents were the most common organic contaminants in mixtures. The sum of benchmark-normalized concentrations was greater than 1 for 58% of samples, suggesting that there could be potential for mixtures toxicity in more than half of the public-well samples. Our findings can be used to help set priorities for groundwater monitoring and suggest future research directions for drinking-water treatment studies and for toxicity assessments of chemical mixtures in water resources. - Highlights: Black-Right-Pointing-Pointer We assessed mixtures in untreated groundwater samples from public

Grand challenge problems in environmental modeling and remediation: groundwater contaminant transport

Energy Technology Data Exchange (ETDEWEB)

Todd Arbogast; Steve Bryant; Clint N. Dawson; Mary F. Wheeler

1998-08-31

This report describes briefly the work of the Center for Subsurface Modeling (CSM) of the University of Texas at Austin (and Rice University prior to September 1995) on the Partnership in Computational Sciences Consortium (PICS) project entitled Grand Challenge Problems in Environmental Modeling and Remediation: Groundwater Contaminant Transport.

Prenatal Exposure of the Northern Quebec Inuit Infants to Environmental Contaminants.

Science.gov (United States)

Muckle, Gina; Ayotte, Pierre; Dewailly, Eric; Jacobson, Sandra W.; Jacobson, Joseph L.

2001-01-01

Through their marine-based diet, the Inuit of Nunavik (Quebec) are exposed to neurotoxic environmental contaminants that impact cognitive development. Mercury levels in Nunavik Inuit mothers and newborns were higher than in U.S. and Canadian populations but lower than in previous Arctic samples. Lead, polychlorinated biphenyls, chorinated…

Comparison of the environmental impacts of two remediation technologies used at hydrocarbon contaminated sites

International Nuclear Information System (INIS)

Viikala, R.; Kuusola, J.

2000-01-01

Investigation and remediation of contaminated sites has rapidly increased in Finland during the last decade. Public organisations as well as private companies are investigating and remediating their properties, e.g. redevelopment or business transactions. Also numerous active and closed gasoline stations have been investigated and remediated during the last few years. Usually the contaminated sites are remediated to limit values regardless of the risk caused by contamination. The limit values currently used in Finland for hydrocarbon remediation at residential or ground water areas are 300 mg/kg of total hydrocarbons and 100 mg/kg of volatile hydrocarbons (boiling point < appr. 200 deg C). Additionally, compounds such as aromatic hydrocarbons have specific limit values. Remediation of hydrocarbon contaminated sites is most often carried out by excavating the contaminated soil and taking it to a landfill by lorries. As distances from the sites to landfills are generally rather long, from tens of kilometres to few hundred kilometres, it is evident that this type of remediation has environmental impacts. Another popular technology used at sites contaminated by volatile hydrocarbons is soil vapour extraction (SVE). SVE is a technique of inducing air flow through unsaturated soils by vapour extraction wells or pipes to remove organic contaminants with an off-gas treatment system. The purpose of this study was to evaluate some of the environmental impacts caused by remediation of hydrocarbon contaminated soil. Energy consumption and air emissions related remedial activities of the two methods were examined in this study. Remediation of the sites used in this study were carried out by Golder Associates Oy in different parts of Finland in different seasons. Evaluation was made by using life cycle assessment based approach

Hazard evaluation of inorganics, singly and in mixtures, to Flannelmouth Sucker Catostomus latipinnis in the San Juan River, New Mexico

Science.gov (United States)

Hamilton, S.J.; Buhl, K.J.

1997-01-01

Larval flannelmouth sucker (Catostomus latipinnis) were exposed to arsenate, boron, copper, molybdenum, selenate, selenite, uranium, vanadium, and zinc singly, and to five mixtures of five to nine inorganics. The exposures were conducted in reconstituted water representative of the San Juan River near Shiprock, New Mexico. The mixtures simulated environmental ratios reported for sites along the San Juan River (San Juan River backwater, Fruitland marsh, Hogback East Drain, Mancos River, and McElmo Creek). The rank order of the individual inorganics, from most to least toxic, was: copper > zinc > vanadium > selenite > selenate > arsenate > uranium > boron > molybdenum. All five mixtures exhibited additive toxicity to flannelmouth sucker. In a limited number of tests, 44-day-old and 13-day-old larvae exhibited no difference in sensitivity to three mixtures. Copper was the major toxic component in four mixtures (San Juan backwater, Hogback East Drain, Mancos River, and McElmo Creek), whereas zinc was the major toxic component in the Fruitland marsh mixture, which did not contain copper. The Hogback East Drain was the most toxic mixture tested. Comparison of 96-h LC50values with reported environmental water concentrations from the San Juan River revealed low hazard ratios for arsenic, boron, molybdenum, selenate, selenite, uranium, and vanadium, moderate hazard ratios for zinc and the Fruitland marsh mixture, and high hazard ratios for copper at three sites and four environmental mixtures representing a San Juan backwater, Hogback East Drain, Mancos River, and McElmo Creek. The high hazard ratios suggest that inorganic contaminants could adversely affect larval flannelmouth sucker in the San Juan River at four sites receiving elevated inorganics.

New trends in the analytical determination of emerging contaminants and their transformation products in environmental waters.

Science.gov (United States)

Agüera, Ana; Martínez Bueno, María Jesús; Fernández-Alba, Amadeo R

2013-06-01

Since the so-called emerging contaminants were established as a new group of pollutants of environmental concern, a great effort has been devoted to the knowledge of their distribution, fate and effects in the environment. After more than 20 years of work, a significant improvement in knowledge about these contaminants has been achieved, but there is still a large gap of information on the growing number of new potential contaminants that are appearing and especially of their unpredictable transformation products. Although the environmental problem arising from emerging contaminants must be addressed from an interdisciplinary point of view, it is obvious that analytical chemistry plays an important role as the first step of the study, as it allows establishing the presence of chemicals in the environment, estimate their concentration levels, identify sources and determine their degradation pathways. These tasks involve serious difficulties requiring different analytical solutions adjusted to purpose. Thus, the complexity of the matrices requires highly selective analytical methods; the large number and variety of compounds potentially present in the samples demands the application of wide scope methods; the low concentrations at which these contaminants are present in the samples require a high detection sensitivity, and high demands on the confirmation and high structural information are needed for the characterisation of unknowns. New developments on analytical instrumentation have been applied to solve these difficulties. Furthermore and not less important has been the development of new specific software packages intended for data acquisition and, in particular, for post-run analysis. Thus, the use of sophisticated software tools has allowed successful screening analysis, determining several hundreds of analytes, and assisted in the structural elucidation of unknown compounds in a timely manner.

Effect of biodegradable amendments on uranium solubility in contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Duquene, L. [Belgian Nuclear Research Centre, Environment Health and Safety, Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium)], E-mail: lduquene@sckcen.be; Tack, F.; Meers, E. [Ghent University, Laboratory for Analytical Chemistry and Applied Ecochemistry, Coupure Links 653, B-9000 Gent (Belgium); Baeten, J. [Katholieke Hogeschool Kempen, Departement of Health-Care and Chemistry, Kleinhoefstraat 4, B-2440 Geel (Belgium); Wannijn, J.; Vandenhove, H. [Belgian Nuclear Research Centre, Environment Health and Safety, Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium)

2008-02-25

Chelate-assisted phytoextraction has been proposed as a potential tool for phytoremediation of U contaminated sites. In this context, the effects of five biodegradable amendments on U release in contaminated soils were evaluated. Three soils were involved in this study, one with a relatively high background level of U, and two which were contaminated with U from industrial effluents. Soils were treated with 5 mmol kg{sup -1} dry weight of either citric acid, NH{sub 4}-citrate/citric acid, oxalic acid, S,S-ethylenediamine disuccinic acid or nitrilotriacetic acid. Soil solution concentration of U was monitored during 2 weeks. All amendments increased U concentration in soil solution, but citric acid and NH{sub 4}-citrate/citric acid mixture were most effective, with up to 479-fold increase. For oxalic acid, S,S-ethylenediamine disuccinic acid and nitrilotriacetic acid, the increase ranged from 10-to 100-fold. The highest concentrations were observed 1 to 7 days after treatment, after which U levels in soil solution gradually decreased. All amendments induced a temporary increase of soil solution pH and TOC that could not be correlated with the release of U in the soil solution. Thermodynamic stability constants (log K) of complexes did not predict the relative efficiency of the selected biodegradable amendments on U release in soil solution. Amendments efficiency was better predicted by the relative affinity of the chelate for Fe compared to U.

INTERACTION’S EFFECT OF ORGANIC MATERIAL AND AGGREGATION ON EXTRACTION EFFICIENCY OF TPHS FROM PETROLEUM CONTAMINATED SOILS WITH MAE

Directory of Open Access Journals (Sweden)

H. Ganjidoust and Gh. Naghizadeh

2005-10-01

Full Text Available Microwave-Assisted Extraction (MAE is a type of low-temperature thermal desorption process that its numerous advantages have caused a wide spread use of it. Microwave heating is a potentially attractive technique as it provides volumetric heating process to improve heating efficiencies as compared with conventional techniques. The ability to rapidly heat the sample solvent mixture is inherent to MAE and the main advantage of this technique. Presently MAE has been shown to be one of the best technologies for removing environmental pollutants specially PAHs, phenols and PCBs from soils and sediments. Five different mixtures and types of aggregation (Sand, Top soil, Kaolinite besides three concentrations of crude oil as a contaminant (1000, 5000 and 10000 mg/L were considered. The results indicated that regardless of aggregation, the presence of humus component in soil reduces the efficiency. Minimum and maximum efficiencies were for sandy soil (containing organic components and kaolinite (without any organic content, respectively. According to the results of this research when some amount of humus and organic materials are available in the matrix, it causes the extraction efficiency to perform as a function of just humus materials but not aggregation. Increasing the concentration of crude oil reduced the efficiency with a sharp steep for higher concentration (5000-10000 mg/L and less steeper for lower concentration (1000-5000 mg/L. The concentration of the contaminant, works just as an independent function with extraction time and aggregation factors. The extraction period of 10 min. can be suggested as an optimum extraction time in FMAE for PAHs contaminated soils.

Epidemiology of Chronic Wasting Disease: PrP(res) Detection, Shedding, and Environmental Contamination

National Research Council Canada - National Science Library

Lewis, Randolph V

2006-01-01

... from orally infected mule and white-tailed deer and elk. Finally these techniques will be applied to investigating the nature of environmental contamination that may be associated with CWD transmission...

Epidemiology of Chronic Wasting Disease: PrP(res) Detection, Shedding, and Environmental Contamination

National Research Council Canada - National Science Library

Williams, Elizabeth S; Miller, Michael W; Lewis, Randolf V; Raisbeck, Merl F; Cook, Walter W

2004-01-01

...) from orally infected mule and white-tailed deer and elk. Finally these techniques will be applied to investigating the nature of environmental contamination that may be associated with CWD transmission...

Phytoremediation potential of willow tress for aquifers contaminated with ethanol-blended gasoline

Energy Technology Data Exchange (ETDEWEB)

Corseuil, H.X. [Universidade Federal de Santa Catarina, Florianopolis (Brazil). Departamento de Engenharia Sanitaria e Ambiental; Moreno, F.N. [Universidade do Sul de Santa Catarina, Palhoca (Brazil). Centro de Ciencias Agrarias e das Engenharias

2001-07-01

Ethanol-blended gasoline has been used in Brazil for 20 years and, probably, is going to be more widely used in North America due to the MtBE environmental effects on groundwater. The potential impacts caused by the presence of ethanol in UST spills are related to the co-solvency effect and the preferential degradation of ethanol over the BTEX compounds. These interactions may increase the length of dissolved hydrocarbon plumes and the costs associated with site remediation. This study investigates the advantages of phytoremediation to overcome the problems associated with the presence of ethanol in groundwater contaminated with gasoline-ethanol mixtures. Experiments were performed under lab conditions with cuttings of Willow tree (Salix babylonica) cultivated hydroponically. Results showed that the cuttings were able to reduce ethanol and benzene concentrations by more than 99% in less than a week. The uptake of both contaminants was confirmed by blank controls and was significantly related to cuttings transpiration capacity. Sorption onto roots biomass also markedly affected the behavior of contaminants in solution. Experiments to evaluate plants' toxicity to ethanol indicated that plants were only affected when aqueous ethanol concentration reached 2000mgl{sup -1}. Results suggest that phytoremediation can be a good complement to intrinsic remediation in shallow aquifer sites contaminated with ethanol-blended gasoline spills. (Author)

Stochastic fuzzy environmental risk characterization of uncertainty and variability in risk assessments: A case study of polycyclic aromatic hydrocarbons in soil at a petroleum-contaminated site in China

International Nuclear Information System (INIS)

Hu, Yan; Wang, Zesen; Wen, Jingya; Li, Yu

2016-01-01

Highlights: • Deal with environmental quality guidelines absence in risk characterization. • Quantitative represention of uncertainty from environmental quality guidelines. • Quantitative represention of variability from contaminant exposure concentrations. • Establishment of stochastic-fuzzy environmental risk characterization approach framework. - Abstract: Better decisions are made using risk assessment models when uncertainty and variability are explicitly acknowledged. Uncertainty caused by a lack of uniform and scientifically supported environmental quality guidelines and variability in the degree of exposure of environmental systems to contaminants are here incorporated in a stochastic fuzzy environmental risk characterization (SFERC) approach. The approach is based on quotient probability distribution and environmental risk level fuzzy membership function methods. The SFERC framework was used to characterize the environmental risks posed by 16 priority polycyclic aromatic hydrocarbons (PAHs) in soil at a typical petroleum-contaminated site in China. This relied on integrating data from the literature and field and laboratory experiments. The environmental risk levels posed by the PAHs under four risk scenarios were determined using the SFERC approach, using “residential land” and “industrial land” environmental quality guidelines under “loose” and “strict” strictness parameters. The results showed that environmental risks posed by PAHs in soil are primarily caused by oil exploitation, traffic emissions, and coal combustion. The SFERC approach is an effective tool for characterizing uncertainty and variability in environmental risk assessments and for managing contaminated sites.

Stochastic fuzzy environmental risk characterization of uncertainty and variability in risk assessments: A case study of polycyclic aromatic hydrocarbons in soil at a petroleum-contaminated site in China

Energy Technology Data Exchange (ETDEWEB)

Hu, Yan [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing 100012 (China); Wang, Zesen [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); Wen, Jingya [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); Institute of Hydropower and Environment Research, Beijing 100012 (China); Li, Yu, E-mail: liyuxx8@hotmail.com [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China)

2016-10-05

Highlights: • Deal with environmental quality guidelines absence in risk characterization. • Quantitative represention of uncertainty from environmental quality guidelines. • Quantitative represention of variability from contaminant exposure concentrations. • Establishment of stochastic-fuzzy environmental risk characterization approach framework. - Abstract: Better decisions are made using risk assessment models when uncertainty and variability are explicitly acknowledged. Uncertainty caused by a lack of uniform and scientifically supported environmental quality guidelines and variability in the degree of exposure of environmental systems to contaminants are here incorporated in a stochastic fuzzy environmental risk characterization (SFERC) approach. The approach is based on quotient probability distribution and environmental risk level fuzzy membership function methods. The SFERC framework was used to characterize the environmental risks posed by 16 priority polycyclic aromatic hydrocarbons (PAHs) in soil at a typical petroleum-contaminated site in China. This relied on integrating data from the literature and field and laboratory experiments. The environmental risk levels posed by the PAHs under four risk scenarios were determined using the SFERC approach, using “residential land” and “industrial land” environmental quality guidelines under “loose” and “strict” strictness parameters. The results showed that environmental risks posed by PAHs in soil are primarily caused by oil exploitation, traffic emissions, and coal combustion. The SFERC approach is an effective tool for characterizing uncertainty and variability in environmental risk assessments and for managing contaminated sites.

Children’s Exposure to Environmental Contaminants: An Editorial Reflection of Articles in the IJERPH Special Issue Entitled, “Children’s Exposure to Environmental Contaminants”

Directory of Open Access Journals (Sweden)

Alesia Ferguson

2016-11-01

Full Text Available Children are at increased vulnerability to many environmental contaminants compared to adults due to their unique behavior patterns, increased contaminant intake per body weight, and developing biological systems. Depending upon their age, young children may crawl on the floor and may practice increased hand to mouth activity that may increase their dose-intake of specific contaminants that accumulate in dust and other matrices. Children are also smaller in size than adults, resulting in a greater body burden for a given contaminant dose. Because children undergo rapid transitions through particular developmental stages they are also especially vulnerable during certain growth-related time windows. A Special Issue was organized focused on the latest findings in the field of children’s environmental exposure for these reasons. This editorial introduces articles in this Special Issue and emphasizes their main findings in advancing the field. From the many articles submitted to this Special Issue from around the world, 23 were accepted and published. They focus on a variety of research areas such as children’s activity patterns, improved risk assessment methods to estimate exposures, and exposures in various contexts and to various contaminants. The future health of a nation relies on protecting the children from adverse exposures and understanding the etiology of childhood diseases. The field of children’s environmental exposures must consider improved and comprehensive research methods aimed at introducing mitigation strategies locally, nationally, and globally. We are happy to introduce a Special Issue focused on children’s environmental exposure and children’s health and hope that it contributes towards improved health of children.

The distribution of environmental contaminants and pharmaceuticals among skim milk, milk fat, curd, whey, and milk protein fractions through milk processing

Science.gov (United States)

Twenty-seven environmental contaminants and pharmaceuticals encompassing a wide range of physicochemical properties were utilized to determine the effects of milk processing on xenobiotic distribution among milk fractions. Target compounds included radiolabeled antibiotics [ciprofloxacin (CIPR), cl...

SUPERCRITICAL FLUID EXTRACTION OF POLYCYCLIC AROMATIC HYDROCARBON MIXTURES FROM CONTAMINATED SOILS

Science.gov (United States)

Highly contaminated (with PAHs) topsoils were extracted with supercritical CO2 to determine the feasibility and mechanism of supercritical fluid extraction (SFE). Effect of SCF density, temperature, cosolvent type and amount, and of slurrying the soil with water were ...

Molds contamination of raw milk and dairy products: Occurrence, diversity and contamination source

Directory of Open Access Journals (Sweden)

T Moshtaghi Maleki

2015-11-01

Full Text Available This study aimed to assess the occurrence and diversity of mold species in raw milk and its products along with the identification of potential contamination sources. For this reason, a total of 260 samples consisting of 80 raw milk, 100 dairy products (i.e., pasteurized milk, yoghurt, cheese and buttermilk and 80 environmental (i.e. ingredients, packaging materials, surface of processing equipments and air specimens were collected. Using culture assay and microscopic observation, the occurrence as well as the diversity of mold species was investigated. According to the results, 82.3% of the samples were identified as positive for mold contamination. The percentage of mold contamination for raw milk was estimated as 97.5%. In the case of pasteurized milk, yoghurt, buttermilk, cheese and environmental samples, it was determined as 52%, 76%, 52%, 56% and 96.25%, respectively. Mold diversity among various samples consisted of Aspergillus, Geotrichum, Penicillium, Mucor, Alternaria, Rhizopus, Stemphylium, Cladosporium, and Fusarium. Results revealed a significant (p < 0.01 correlation between kind of mold species isolated from raw milk and dairy products. Similarly, a correlation was observed between dairy products and environmental sources. Regarding the high occurrence of mold contamination in raw milk and environmental sources, it seems that in some instances heat treatment was not effective enough to inactivate all molds; whereas in some other cases, cross contamination may have resulted in mold contamination. Therefore, it is crucial to maintain hygienic conditions during raw milk handling as well as processing steps. These practices could efficiently reduce the occurrence of mold contaminations in dairy products.

Sublethal effects of contamination on the Mediterranean sponge Crambe crambe: metal accumulation and biological responses

International Nuclear Information System (INIS)

Cebrian, E.; Marti, R.; Uriz, J.M.; Turon, X.

2003-01-01

The effect of low levels of pollution on the growth, reproduction output, morphology and survival of adult sponges and settlers of the sponge Crambe crambe were examined. We transplanted sponges from a control area to a contaminated site and measured the main environmental variables (chemical and physical) of both sites during the study period. Except some punctual differences in particulate organic matter, silicates, nitrates, and water motion, most environmental variables in the water were similar at both sites during the study months. Mainly copper, lead and OM concentrations in the sediment, and water motion were significantly higher at the polluted site and may be implicated in the biological effects observed: decrease in the percentage of specimens with embryos, increase in shape irregularity and decrease in growth rate. Individuals naturally occurring at the polluted site and those transplanted there for four months accumulated ten times more copper than either untouched or transplant controls. Although lead concentration in sediment did not differ between sites, native specimens from the contaminated site accumulated this metal more than untouched controls. Vanadium concentration also tended to increase in the sponges living at or transplanted to the contaminated site but this difference was not significant. C. crambe is a reliable indicator of metal contamination since it accumulates copper, lead and vanadium in high amounts. At the contaminated site, sponge growth, fecundity and survival were inhibited, whereas sponge irregularity ending in sponge fission was promoted. All these effects may compromise the structure and dynamics of the sponge populations in sheltered, metal-contaminated habitats

Environmental liability and contaminated site management : a strategic approach for Saskatchewan

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-12-31

The issue of how much liability can be imposed on a party for remediating a contaminated site is discussed. Many jurisdictions have either passed legislation or implemented policies on environmental liability consistent with the 1993 framework outlined by the Canadian Council of Ministers of the Environment (CCME). In 1997, the Minister of Saskatchewan Environment and Resource Management (SERM) received a report from the Minister`s Contaminated Site Liability Advisory Group (CSLAG) which made a series of recommendations on the application of CCME principles in a Saskatchewan context. This document clarifies SERM`s approach to the management of contaminated sites in Saskatchewan and proposes a process model in accordance with the principles outlined by CCME and CSLAG to provide a workable system for determining which remedial measures are appropriate for specific contaminated sites. The report also identifies the parties responsible for implementing remedial measures and encourages them to negotiate the sharing of responsibility for the remediation among themselves. The treatment of orphan shares/sites is also discussed. 1 fig.

Electrochemical Biosensors: A Solution to Pollution Detection with Reference to Environmental Contaminants

Directory of Open Access Journals (Sweden)

Gustavo Hernandez-Vargas

2018-03-01

Full Text Available The increasing environmental pollution with particular reference to emerging contaminants, toxic heavy elements, and other hazardous agents is a serious concern worldwide. Considering this global issue, there is an urgent need to design and develop strategic measuring techniques with higher efficacy and precision to detect a broader spectrum of numerous contaminants. The development of precise instruments can further help in real-time and in-process monitoring of the generation and release of environmental pollutants from different industrial sectors. Moreover, real-time monitoring can also reduce the excessive consumption of several harsh chemicals and reagents with an added advantage of on-site determination of contaminant composition prior to discharge into the environment. With key scientific advances, electrochemical biosensors have gained considerable attention to solve this problem. Electrochemical biosensors can be an excellent fit as an analytical tool for monitoring programs to implement legislation. Herein, we reviewed the current trends in the use of electrochemical biosensors as novel tools to detect various contaminant types including toxic heavy elements. A particular emphasis was given to screen-printed electrodes, nanowire sensors, and paper-based biosensors and their role in the pollution detection processes. Towards the end, the work is wrapped up with concluding remarks and future perspectives. In summary, electrochemical biosensors and related areas such as bioelectronics, and (bio-nanotechnology seem to be growing areas that will have a marked influence on the development of new bio-sensing strategies in future studies.

Electrochemical Biosensors: A Solution to Pollution Detection with Reference to Environmental Contaminants.

Science.gov (United States)

Hernandez-Vargas, Gustavo; Sosa-Hernández, Juan Eduardo; Saldarriaga-Hernandez, Sara; Villalba-Rodríguez, Angel M; Parra-Saldivar, Roberto; Iqbal, Hafiz M N

2018-03-24

The increasing environmental pollution with particular reference to emerging contaminants, toxic heavy elements, and other hazardous agents is a serious concern worldwide. Considering this global issue, there is an urgent need to design and develop strategic measuring techniques with higher efficacy and precision to detect a broader spectrum of numerous contaminants. The development of precise instruments can further help in real-time and in-process monitoring of the generation and release of environmental pollutants from different industrial sectors. Moreover, real-time monitoring can also reduce the excessive consumption of several harsh chemicals and reagents with an added advantage of on-site determination of contaminant composition prior to discharge into the environment. With key scientific advances, electrochemical biosensors have gained considerable attention to solve this problem. Electrochemical biosensors can be an excellent fit as an analytical tool for monitoring programs to implement legislation. Herein, we reviewed the current trends in the use of electrochemical biosensors as novel tools to detect various contaminant types including toxic heavy elements. A particular emphasis was given to screen-printed electrodes, nanowire sensors, and paper-based biosensors and their role in the pollution detection processes. Towards the end, the work is wrapped up with concluding remarks and future perspectives. In summary, electrochemical biosensors and related areas such as bioelectronics, and (bio)-nanotechnology seem to be growing areas that will have a marked influence on the development of new bio-sensing strategies in future studies.

Comparative evaluation of environmental contamination and DNA damage induced by electronic-waste in Nigeria and China.

Science.gov (United States)

Alabi, Okunola A; Bakare, Adekunle A; Xu, Xijin; Li, Bin; Zhang, Yuling; Huo, Xia

2012-04-15

In the last decade, China and Nigeria have been prime destinations for the world's e-waste disposal leading to serious environmental contamination. We carried out a comparative study of the level of contamination using soils and plants from e-waste dumping and processing sites in both countries. Levels of polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were analyzed using gas chromatography/spectrophotometry and heavy metals using atomic absorption spectrophotometry. DNA damage was assayed in human peripheral blood lymphocytes using an alkaline comet assay. Soils and plants were highly contaminated with toxic PAHs, PCBs, PBDEs, and heavy metals in both countries. Soil samples from China and plant samples from Nigeria were more contaminated. There was a positive correlation between the concentrations of organics and heavy metals in plant samples and the surrounding soils. In human lymphocytes, all tested samples induced significant (pwaste components/constituents can accumulate, in soil and surrounding vegetation, to toxic and genotoxic levels that could induce adverse health effects in exposed individuals. Copyright © 2012 Elsevier B.V. All rights reserved.

Bayesian evidence and epidemiological implications of environmental contamination from acute respiratory infection in long-term care facilities.

Science.gov (United States)

Diaz-Decaro, J D; Launer, B; Mckinnell, J A; Singh, R; Dutciuc, T D; Green, N M; Bolaris, M; Huang, S S; Miller, L G

2018-05-01

Skilled nursing home facilities (SNFs) house a vulnerable population frequently exposed to respiratory pathogens. Our study aims to gain a better understanding of the transmission of nursing home-acquired viral respiratory infections in non-epidemic settings. Symptomatic surveillance was performed in three SNFs for residents exhibiting acute respiratory symptoms. Environmental surveillance of five high-touch areas was performed to assess possible transmission. All resident and environmental samples were screened using a commercial multiplex polymerase chain reaction platform. Bayesian methods were used to evaluate environmental contamination. Among nursing home residents with respiratory symptoms, 19% had a detectable viral pathogen (parainfluenza-3, rhinovirus/enterovirus, RSV, or influenza B). Environmental contamination was found in 20% of total room surface swabs of symptomatic residents. Environmental and resident results were all concordant. Target period prevalence among symptomatic residents ranged from 5.5 to 13.3% depending on target. Bayesian analysis quantifies the probability of environmental shedding due to parainfluenza-3 as 92.4% (95% CI: 86.8-95.8%) and due to rhinovirus/enterovirus as 65.6% (95% CI: 57.9-72.5%). Our findings confirm that non-epidemic viral infections are common among SNF residents exhibiting acute respiratory symptoms and that environmental contamination may facilitate further spread with considerable epidemiological implications. Findings further emphasise the importance of environmental infection control for viral respiratory pathogens in long-term care facilities.

Interactions and Toxicity of Cu-Zn mixtures to Hordeum vulgare in Different Soils Can Be Rationalized with Bioavailability-Based Prediction Models.

Science.gov (United States)

Qiu, Hao; Versieren, Liske; Rangel, Georgina Guzman; Smolders, Erik

2016-01-19

Soil contamination with copper (Cu) is often associated with zinc (Zn), and the biological response to such mixed contamination is complex. Here, we investigated Cu and Zn mixture toxicity to Hordeum vulgare in three different soils, the premise being that the observed interactions are mainly due to effects on bioavailability. The toxic effect of Cu and Zn mixtures on seedling root elongation was more than additive (i.e., synergism) in soils with high and medium cation-exchange capacity (CEC) but less than additive (antagonism) in a low-CEC soil. This was found when we expressed the dose as the conventional total soil concentration. In contrast, antagonism was found in all soils when we expressed the dose as free-ion activities in soil solution, indicating that there is metal-ion competition for binding to the plant roots. Neither a concentration addition nor an independent action model explained mixture effects, irrespective of the dose expressions. In contrast, a multimetal BLM model and a WHAM-Ftox model successfully explained the mixture effects across all soils and showed that bioavailability factors mainly explain the interactions in soils. The WHAM-Ftox model is a promising tool for the risk assessment of mixed-metal contamination in soils.

Wind Integration into Various Generation Mixtures

NARCIS (Netherlands)

Maddaloni, J.D.; Rowe, A.M.; Kooten, van G.C.

2009-01-01

A load balance model is used to quantify the economic and environmental effects of integrating wind power into three typical generation mixtures. System operating costs over a specified period are minimized by controlling the operating schedule of the existing power generating facilities for a range

HEIS: An integrated information system for environmental restoration and monitoring at Hanford

Energy Technology Data Exchange (ETDEWEB)

Tzemos, S.; Kissinger, B.

1991-11-01

The US Department of Energy`s Hanford Site has about 1500 waste sites that contain a complex mixture of chemical and radioactive contaminants. After many years of environmental monitoring to assess the impact of Hanford operations to the environment, the Site`s mission is shifting to environmental restoration. The Hanford Environmental Information System (HEIS) is being developed to provide advanced tools to (1) support environmental restoration and routine site-wide monitoring, and (2) aid the scientists in understanding and conducting the restoration efforts. This paper describes some of the highlights and distinctive features of HEIS.

ENVIRONMENTAL CONTAMINANTS AND POTENTIAL HUMAN RISK ASSOCIATED WITH SELECTED BOTANICAL DIETARY SUPPLEMENTS

Science.gov (United States)

Botanical dietary supplements have a long history of use in Europe and China and they are becoming increasingly popular in the United States. However, little data is available regarding environmental contaminants in botanical dietary supplements and the risk posed to those ingest...

Bioaugmentation of soil contaminated with high-level crude oil through inoculation with mixed cultures including Acremonium sp.

Science.gov (United States)

Ma, Xiao-Kui; Ding, Ning; Peterson, Eric Charles

2015-06-01

Heavy contamination of soil with crude oil has caused significant negative environmental impacts and presents substantial hazards to human health. To explore a highly efficient bioaugmentation strategy for these contaminations, experiments were conducted over 180 days in soil heavily contaminated with crude oil (50,000 mg kg(-1)), with four treatments comprised of Bacillus subtilis inoculation with no further inoculation (I), or reinoculation after 100 days with either B. subtilis (II), Acremonium sp.(III), or a mixture of both organisms (IV). The removal values of total petroleum hydrocarbons were 60.1 ± 2.0, 60.05 ± 3.0, 71.3 ± 5.2 and 74.2 ± 2.7 % for treatment (I-IV), respectively. Treatments (III-IV) significantly enhanced the soil bioremediation compared with treatments (I-II) (p oil heavy fractions. Dehydrogenase activity in treatment (III-IV) containing Acremonium sp. showed a constant increase until the end of experiments. Therefore reinoculation with pure fungus or fungal-bacterial consortium should be considered as an effective strategy in bioaugmentation for soil heavily contaminated with crude oil.

Model-based experimental design for assessing effects of mixtures of chemicals

Energy Technology Data Exchange (ETDEWEB)

Baas, Jan, E-mail: jan.baas@falw.vu.n [Vrije Universiteit of Amsterdam, Dept of Theoretical Biology, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands); Stefanowicz, Anna M., E-mail: anna.stefanowicz@uj.edu.p [Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Krakow (Poland); Klimek, Beata, E-mail: beata.klimek@uj.edu.p [Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Krakow (Poland); Laskowski, Ryszard, E-mail: ryszard.laskowski@uj.edu.p [Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Krakow (Poland); Kooijman, Sebastiaan A.L.M., E-mail: bas@bio.vu.n [Vrije Universiteit of Amsterdam, Dept of Theoretical Biology, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands)

2010-01-15

We exposed flour beetles (Tribolium castaneum) to a mixture of four poly aromatic hydrocarbons (PAHs). The experimental setup was chosen such that the emphasis was on assessing partial effects. We interpreted the effects of the mixture by a process-based model, with a threshold concentration for effects on survival. The behavior of the threshold concentration was one of the key features of this research. We showed that the threshold concentration is shared by toxicants with the same mode of action, which gives a mechanistic explanation for the observation that toxic effects in mixtures may occur in concentration ranges where the individual components do not show effects. Our approach gives reliable predictions of partial effects on survival and allows for a reduction of experimental effort in assessing effects of mixtures, extrapolations to other mixtures, other points in time, or in a wider perspective to other organisms. - We show a mechanistic approach to assess effects of mixtures in low concentrations.

Model-based experimental design for assessing effects of mixtures of chemicals

International Nuclear Information System (INIS)

Baas, Jan; Stefanowicz, Anna M.; Klimek, Beata; Laskowski, Ryszard; Kooijman, Sebastiaan A.L.M.

2010-01-01

We exposed flour beetles (Tribolium castaneum) to a mixture of four poly aromatic hydrocarbons (PAHs). The experimental setup was chosen such that the emphasis was on assessing partial effects. We interpreted the effects of the mixture by a process-based model, with a threshold concentration for effects on survival. The behavior of the threshold concentration was one of the key features of this research. We showed that the threshold concentration is shared by toxicants with the same mode of action, which gives a mechanistic explanation for the observation that toxic effects in mixtures may occur in concentration ranges where the individual components do not show effects. Our approach gives reliable predictions of partial effects on survival and allows for a reduction of experimental effort in assessing effects of mixtures, extrapolations to other mixtures, other points in time, or in a wider perspective to other organisms. - We show a mechanistic approach to assess effects of mixtures in low concentrations.

Electrokinetic applications for environmental restoration, waste volume reduction, and contaminant containment systems

International Nuclear Information System (INIS)

Lomasney, H.L.; Lomasney, C.A.

1996-01-01

In the US and all over the world, following over 50 years of nuclear arms production operations, the magnitude of resultant environmental damage is only beginning to surface. The US Department of Energy estimates that by the year 2070, the total volume of high-level waste, transuranic waste, low-level waste, and low-level mixed waste, generated as a result of past and current nuclear activities, will exceed 20 million cubic meters. In Russia, it is reported that more than 30% of all groundwater is contaminated with agricultural and industrial chemical waste. Government agencies today are faced with the responsibility of developing technologies that are suitable for dealing with severe environmental contamination and accumulating waste inventories. In response to this demand, applications of electrokinetics have emerged in the field of environmental waste management as alternatives for environmental decontamination and ecological protection. Electrokinetics involves the movement of charged species under the influence of an applied electric field and is applicable in several areas of environmental waste management, including cleanup of soil and groundwater, barrier detection, and emergency or protective fencing. The worldwide interest in this technology has steadily escalated over the past decade. Today, state-of-the-art applications of electrokinetics have been demonstrated in the US, The Netherlands, Russia, The Ukraine, and India. This paper addresses the latest advances in the various applications of this technology as well as the most significant breakthroughs in the history of electrokinetics

Environmental Monitoring of Agro-Ecosystem Using Environmental Isotope Tracer Technology

International Nuclear Information System (INIS)

Chung, Byung Yeoup; Kim, Jae Sung; Cho, Jae Young

2004-10-01

This report has provided the counterparts the knowledge and skills on the use of environmental isotope tracer technology for obtaining valuable information on agricultural non-point pollution source in agro-ecosystem. The contamination from agricultural watersheds has been brought into attention as a potential contaminant of streams and tributaries, since majority of them caused water quality degradation, eutrophication of reservoir and negative effect on agro-environment. To prevent the contamination from these watersheds, it is necessary to find out the source of the contamination. However, accurate contaminants outflows from various types of non-point sources have not yet been elucidated due to the fact that the extent of non-point source contaminants related to uncontrollable climatic events and irrigation conditions may differ greatly from place to place and year to year. The dominant use of isotopes in environmental ecosystem research in the last few decades has been to trace sources of waters and solutes. The environmental isotope tracer technology using stable isotopes such as oxygen, hydrogen, carbon, nitrogen, and sulfur has extensively been used for tracing the fate of environmental pollutants and for identification of environmental pollutants sources in agro-ecosystems

Contamination of environmental surfaces by methicillin-resistant Staphylococcus aureus (MRSA) in rooms of inpatients with MRSA-positive body sites.

Science.gov (United States)

Kurashige, E Jessica Ohashi; Oie, Shigeharu; Furukawa, H

2016-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) can contaminate environmental surfaces that are frequently touched by the hands of patients with MRSA colonization/infection. There have been many studies in which the presence or absence of MRSA contamination was determined but no studies in which MRSA contamination levels were also evaluated in detail. We evaluated MRSA contamination of environmental surfaces (overbed tables, bed side rails, and curtains) in the rooms of inpatients from whom MRSA was isolated via clinical specimens. We examined the curtains within 7-14 days after they had been newly hung. The environmental surfaces were wiped using gauze (molded gauze for wiping of surface bacteria; 100% cotton, 4cm×8cm) moistened with sterile physiological saline. The MRSA contamination rate and mean counts (range) were 25.0% (6/24 samples) and 30.6 (0-255)colony-forming units (cfu)/100cm(2), respectively, for the overbed tables and 31.6% (6/19 samples) and 159.5 (0-1620)cfu/100cm(2), respectively, for the bed side rails. No MRSA was detected in 24 curtain samples. The rate of MRSA contamination of environmental surfaces was high for the overbed tables and bed side rails but low for the curtains. Therefore, at least until the 14th day of use, frequent disinfection of curtains may be not necessary. Copyright © 2016. Published by Elsevier Editora Ltda.

Environmental contaminants and microRNA regulation: Transcription factors as regulators of toxicant-altered microRNA expression

Energy Technology Data Exchange (ETDEWEB)

Sollome, James; Martin, Elizabeth [Department of Environmental Science & Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill (United States); Sethupathy, Praveen [Department of Genetics, School of Medicine, University of North Carolina, Chapel Hill, NC (United States); Fry, Rebecca C., E-mail: rfry@unc.edu [Department of Environmental Science & Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill (United States); Curriculum in Toxicology, School of Medicine, University of North Carolina, Chapel Hill, NC (United States)

2016-12-01

MicroRNAs (miRNAs) regulate gene expression by binding mRNA and inhibiting translation and/or inducing degradation of the associated transcripts. Expression levels of miRNAs have been shown to be altered in response to environmental toxicants, thus impacting cellular function and influencing disease risk. Transcription factors (TFs) are known to be altered in response to environmental toxicants and play a critical role in the regulation of miRNA expression. To date, environmentally-responsive TFs that are important for regulating miRNAs remain understudied. In a state-of-the-art analysis, we utilized an in silico bioinformatic approach to characterize potential transcriptional regulators of environmentally-responsive miRNAs. Using the miRStart database, genomic sequences of promoter regions for all available human miRNAs (n = 847) were identified and promoter regions were defined as − 1000/+500 base pairs from the transcription start site. Subsequently, the promoter region sequences of environmentally-responsive miRNAs (n = 128) were analyzed using enrichment analysis to determine overrepresented TF binding sites (TFBS). While most (56/73) TFs differed across environmental contaminants, a set of 17 TFs was enriched for promoter binding among miRNAs responsive to numerous environmental contaminants. Of these, one TF was common to miRNAs altered by the majority of environmental contaminants, namely SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 3 (SMARCA3). These identified TFs represent candidate common transcriptional regulators of miRNAs perturbed by environmental toxicants. - Highlights: • Transcription factors that regulate environmentally-modulated miRNA expression are understudied • Transcription factor binding sites (TFBS) located within DNA promoter regions of miRNAs were identified. • Specific transcription factors may serve as master regulators of environmentally-mediated microRNA expression.

Environmental contaminants and microRNA regulation: Transcription factors as regulators of toxicant-altered microRNA expression

International Nuclear Information System (INIS)

Sollome, James; Martin, Elizabeth; Sethupathy, Praveen; Fry, Rebecca C.

2016-01-01

MicroRNAs (miRNAs) regulate gene expression by binding mRNA and inhibiting translation and/or inducing degradation of the associated transcripts. Expression levels of miRNAs have been shown to be altered in response to environmental toxicants, thus impacting cellular function and influencing disease risk. Transcription factors (TFs) are known to be altered in response to environmental toxicants and play a critical role in the regulation of miRNA expression. To date, environmentally-responsive TFs that are important for regulating miRNAs remain understudied. In a state-of-the-art analysis, we utilized an in silico bioinformatic approach to characterize potential transcriptional regulators of environmentally-responsive miRNAs. Using the miRStart database, genomic sequences of promoter regions for all available human miRNAs (n = 847) were identified and promoter regions were defined as − 1000/+500 base pairs from the transcription start site. Subsequently, the promoter region sequences of environmentally-responsive miRNAs (n = 128) were analyzed using enrichment analysis to determine overrepresented TF binding sites (TFBS). While most (56/73) TFs differed across environmental contaminants, a set of 17 TFs was enriched for promoter binding among miRNAs responsive to numerous environmental contaminants. Of these, one TF was common to miRNAs altered by the majority of environmental contaminants, namely SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 3 (SMARCA3). These identified TFs represent candidate common transcriptional regulators of miRNAs perturbed by environmental toxicants. - Highlights: • Transcription factors that regulate environmentally-modulated miRNA expression are understudied • Transcription factor binding sites (TFBS) located within DNA promoter regions of miRNAs were identified. • Specific transcription factors may serve as master regulators of environmentally-mediated microRNA expression

Environmental Effects of BPA

Directory of Open Access Journals (Sweden)

Laura Canesi

2015-07-01

Full Text Available Research on bisphenol A (BPA as an environmental contaminant has now major regulatory implications toward the ecosystem health, and hence it is incumbent on scientists to do their research to the highest standards possible, in order that the most appropriate decisions are made to mitigate the impacts to aquatic wildlife. However, the contribution given so far appears rather fragmented. The present overview aims to collect available information on the effects of BPA on aquatic vertebrates and invertebrates to provide a general scenario and to suggest future developments toward more comprehensive approaches useful for aquatic species protection.

Unit environmental transport assessment of contaminants from Hanford's past-practice waste sites. Hanford Remedial Action Environmental Impact Statement

International Nuclear Information System (INIS)

Whelan, G.; Buck, J.W.; Castleton, K.J.

1995-06-01

The US Department of Energy, Richland Operations Office (DOE-RL) contracted Pacific Northwest Laboratory (PNL) to provide support to Advanced Sciences, Incorporated (ASI) in implementing tile regional no-action risk assessment in the Hanford Remedial Action Environmental Impact Statement. Researchers at PNL were charged with developing unit concentrations for soil, groundwater, surface water, and air at multiple locations within an 80-km radius from the center of tile Hanford installation. Using the Multimedia Environmental Pollutant Assessment System (MEPAS), PNL simulated (1) a unit release of one ci for each radionuclide and one kg for each chemical from contaminated soils and ponded sites, (2) transport of the contaminants in and through various environmental media and (3) exposure/risk of four exposure scenarios, outlined by the Hanford Site Baseline Remedial Action Methodology. These four scenarios include residential, recreational, industrial, and agricultural exposures. Spacially and temporally distributed environmental concentrations based on unit releases of radionuclides and chemicals were supported to ASI in support of the HRA-EIS. Risk for the four exposure scenarios, based on unit environment concentrations in air, water, and soil. were also supplied to ASI. This report outlines the procedure that was used to implement the unit transport portion of the HRA-EIS baseline risk assessment. Deliverables include unit groundwater, surface water, air, and soil concentrations at multiple locations within an 80-km radius from the center of the Hanford installation

Release of polyaromatic hydrocarbons from coal tar contaminated soils

International Nuclear Information System (INIS)

Priddy, N.D.; Lee, L.S.

1996-01-01

A variety of process wastes generated from manufactured gas production (MGP) have contaminated soils and groundwater at production and disposal sites. Coal tar, consisting of a complex mixture of hydrocarbons present as a nonaqueous phase liquid, makes up a large portion of MGP wastes. Of the compounds in coal tar, polyaromatic hydrocarbons (PAHs) are the major constituents of environmental concern due to their potential mutagenic and carcinogenic hazards. Characterization of the release of PAHs from the waste-soil matrix is essential to quantifying long-term environmental impacts in soils and groundwater. Currently, conservative estimates for the release of PAHs to the groundwater are made assuming equilibrium conditions and using relationships derived from artificially contaminated soils. Preliminary work suggests that aged coal tar contaminated soils have much lower rates of desorption and a greater affinity for retaining organic contaminants. To obtain better estimates of desorption rates, the release of PAHs from a coal tar soil was investigated using a flow-interruption, miscible displacement technique. Methanol/water solutions were employed to enhance PAH concentrations above limits of detection. For each methanol/water solution employed, a series of flow interrupts of varying times was invoked. Release rates from each methanol/water solution were estimated from the increase in concentration with duration of flow interruption. Aqueous-phase release rates were then estimated by extrapolation using a log-linear cosolvency model

Environmental Contamination and Viral Shedding in MERS Patients During MERS-CoV Outbreak in South Korea.

Science.gov (United States)

Bin, Seo Yu; Heo, Jung Yeon; Song, Min-Suk; Lee, Jacob; Kim, Eun-Ha; Park, Su-Jin; Kwon, Hyeok-Il; Kim, Se Mi; Kim, Young-Il; Si, Young-Jae; Lee, In-Won; Baek, Yun Hee; Choi, Won-Suk; Min, Jinsoo; Jeong, Hye Won; Choi, Young Ki

2016-03-15

Although Middle East Respiratory Syndrome coronavirus (MERS-CoV) is characterized by a risk of nosocomial transmission, the detailed mode of transmission and period of virus shedding from infected patients are poorly understood. The aims of this study were to investigate the potential role of environmental contamination by MERS-CoV in healthcare settings and to define the period of viable virus shedding from MERS patients. We investigated environmental contamination from 4 patients in MERS-CoV units of 2 hospitals. MERS-CoV was detected by reverse transcription polymerase chain reaction (PCR) and viable virus was isolated by cultures. Many environmental surfaces of MERS patient rooms, including points frequently touched by patients or healthcare workers, were contaminated by MERS-CoV. Viral RNA was detected up to five days from environmental surfaces following the last positive PCR from patients' respiratory specimens. MERS-CoV RNA was detected in samples from anterooms, medical devices, and air-ventilating equipment. In addition, MERS-CoV was isolated from environmental objects such as bed sheets, bedrails, IV fluid hangers, and X-ray devices. During the late clinical phase of MERS, viable virus could be isolated in 3 of the 4 enrolled patients on day 18 to day 25 after symptom onset. Most of touchable surfaces in MERS units were contaminated by patients and health care workers and the viable virus could shed through respiratory secretion from clinically fully recovered patients. These results emphasize the need for strict environmental surface hygiene practices, and sufficient isolation period based on laboratory results rather than solely on clinical symptoms. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Thermal Coatings Seminar Series Training Part 2: Environmental Effects

Science.gov (United States)

Triolo, Jack

2015-01-01

This course will present an overview of a variety of thermal coatings-related topics, including: coating types and availability, thermal properties measurements, environmental testing (lab and in-flight), environmental impacts, contamination impacts, contamination liabilities, determination of BOLEOL values, and what does specularity mean to the thermal engineer.

Metal contamination in environmental media in residential areas around Romanian mining sites

Science.gov (United States)

Hard-rock mining for metals, such as gold, silver, copper, zinc, iron and others, is recognized to have a significant impact on the environmental media, soil and water, in particular. Toxic contaminants released from mine waste to surface water and groundwater is the primary co...

The effects of perennial ryegrass and alfalfa on microbial abundance and diversity in petroleum contaminated soil

International Nuclear Information System (INIS)

Kirk, Jennifer L.; Klironomos, John N.; Lee, Hung; Trevors, Jack T.

2005-01-01

Enhanced rhizosphere degradation uses plants to stimulate the rhizosphere microbial community to degrade organic contaminants. We measured changes in microbial communities caused by the addition of two species of plants in a soil contaminated with 31,000 ppm of total petroleum hydrocarbons. Perennial ryegrass and/or alfalfa increased the number of rhizosphere bacteria in the hydrocarbon-contaminated soil. These plants also increased the number of bacteria capable of petroleum degradation as estimated by the most probable number (MPN) method. Eco-Biolog plates did not detect changes in metabolic diversity between bulk and rhizosphere samples but denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified partial 16S rDNA sequences indicated a shift in the bacterial community in the rhizosphere samples. Dice coefficient matrices derived from DGGE profiles showed similarities between the rhizospheres of alfalfa and perennial ryegrass/alfalfa mixture in the contaminated soil at week seven. Perennial ryegrass and perennial ryegrass/alfalfa mixture caused the greatest change in the rhizosphere bacterial community as determined by DGGE analysis. We concluded that plants altered the microbial population; these changes were plant-specific and could contribute to degradation of petroleum hydrocarbons in contaminated soil. - Plant-specific changes in microbial populations on roots affect degradation of petroleum hydrocarbons in contaminated soil

Electrokinetic-enhanced bioremediation of organic contaminants: a review of processes and environmental applications.

Science.gov (United States)

Gill, R T; Harbottle, M J; Smith, J W N; Thornton, S F

2014-07-01

There is current interest in finding sustainable remediation technologies for the removal of contaminants from soil and groundwater. This review focuses on the combination of electrokinetics, the use of an electric potential to move organic and inorganic compounds, or charged particles/organisms in the subsurface independent of hydraulic conductivity; and bioremediation, the destruction of organic contaminants or attenuation of inorganic compounds by the activity of microorganisms in situ or ex situ. The objective of the review is to examine the state of knowledge on electrokinetic bioremediation and critically evaluate factors which affect the up-scaling of laboratory and bench-scale research to field-scale application. It discusses the mechanisms of electrokinetic bioremediation in the subsurface environment at different micro and macroscales, the influence of environmental processes on electrokinetic phenomena and the design options available for application to the field scale. The review also presents results from a modelling exercise to illustrate the effectiveness of electrokinetics on the supply electron acceptors to a plume scale scenario where these are limiting. Current research needs include analysis of electrokinetic bioremediation in more representative environmental settings, such as those in physically heterogeneous systems in order to gain a greater understanding of the controlling mechanisms on both electrokinetics and bioremediation in those scenarios. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Effects-based spatial assessment of contaminated estuarine sediments from Bear Creek, Baltimore Harbor, MD, USA.

Science.gov (United States)

Hartzell, Sharon E; Unger, Michael A; McGee, Beth L; Wilson, Sacoby M; Yonkos, Lance T

2017-10-01

Estuarine sediments in regions with prolonged histories of industrial activity are often laden to significant depths with complex contaminant mixtures, including trace metals and persistent organic pollutants. Given the complexity of assessing risks from multi-contaminant exposures, the direct measurement of impacts to biological receptors is central to characterizing contaminated sediment sites. Though biological consequences are less commonly assessed at depth, laboratory-based toxicity testing of subsurface sediments can be used to delineate the scope of contamination at impacted sites. The extent and depth of sediment toxicity in Bear Creek, near Baltimore, Maryland, USA, was delineated using 10-day acute toxicity tests with the estuarine amphipod Leptocheirus plumulosus, and chemical analysis of trace metals and persistent organic pollutants. A gradient of toxicity was demonstrated in surface sediments with 21 of 22 tested sites differing significantly from controls. Effects were most pronounced (100% lethality) at sites proximate to a historic industrial complex. Sediments from eight of nine core samples to depths of 80 cm were particularly impacted (i.e., caused significant lethality to L. plumulosus) even in locations overlain with relatively non-toxic surface sediments, supporting a conclusion that toxicity observed at the surface (top 2 cm) does not adequately predict toxicity at depth. In seven of nine sites, toxicity of surface sediments differed from toxicity at levels beneath by 28 to 69%, in five instances underestimating toxicity (28 to 69%), and in two instances overestimating toxicity (44 to 56%). Multiple contaminants exceeded sediment quality guidelines and correlated positively with toxic responses within surface sediments (e.g., chromium, nickel, polycyclic aromatic hydrocarbon (PAH), total petroleum hydrocarbon). Use of an antibody-based PAH biosensor revealed that porewater PAH concentrations also increased with depth at most sites. This

Uranium: properties and biological effects after internal contamination

International Nuclear Information System (INIS)

Souidi, M.; Tissandie, E.; Racine, R.; Ben Soussan, H.; Rouas, C.; Grignard, E.; Dublineau, I.; Gourmelon, P.; Lestaevel, P.; Gueguen, Y.

2009-01-01

Uranium is a radionuclide present in the environment since the origin of the Earth. In addition to natural uranium, recent deposits from industrial or military activities are acknowledged. Uranium's toxicity is due to a combination of its chemical (heavy metal) and radiological properties (emission of ionizing radiations). Acute toxicity induces an important weight loss and signs of renal and cerebral impairment. Alterations of bone growth, modifications of the reproductive system and carcinogenic effects are also often seen. On the contrary, the biological effects of a chronic exposure to low doses are unwell known. However, results from different recent studies suggest that a chronic contamination with low levels of uranium induces subtle but significant levels. Indeed, an internal contamination of rats for several weeks leads to detection of uranium in many cerebral structures, in association with an alteration of short-term memory and an increase of anxiety level. Biological effects of uranium on the metabolisms of xenobiotics, steroid hormones and vitamin D were described in the liver, testis and kidneys. These recent scientific data suggest that uranium could participate to increase of health risks linked to environmental pollution. (authors)

Use of liquid nitrogen during storage in a cell and tissue bank: contamination risk and effect on the detectability of potential viral contaminants.

Science.gov (United States)

Mirabet, Vicente; Alvarez, Manuel; Solves, Pilar; Ocete, Dolores; Gimeno, Concepción

2012-04-01

Cryopreservation is widely used for banking cells and tissues intended for transplantation. Liquid nitrogen provides a very stable ultra-low temperature environment. Thus, it is used for longterm storage. Unlike the exhaustive microbiological monitoring of the environmental conditions during tissue processing, storage is not usually considered as a critical point of potential contamination risk in professional standards for cell and tissue banking. We have analysed the presence of microbial agents inside our nitrogen tanks. We have mainly detected environmental and water-borne bacteria and fungi. In addition, we have studied the effect of liquid nitrogen exposure on virus detectability. Only differences for hepatitis C virus RNA were observed. Measures for contamination risk reduction during storage must be mandatory in cell and tissue banking. Copyright © 2011 Elsevier Inc. All rights reserved.

Perinatal exposure to a mixture of persistent pollutants based on blood profiles of Arctic populations affects bone parameters in 35 days old rats

Energy Technology Data Exchange (ETDEWEB)

Stern, N.; Trossvik, C.; Hakansson, H. [Inst. of Environmental Medicine, Karolinska Inst., Stockholm (Sweden); Bowers, W.; Nakai, J.S.; Chu, I. [Environmental and Occupational Toxicology Div., Environmental Health Sciences Bureau, Health Canada, Ottawa (Canada)

2004-09-15

Environmental pollution of Arctic regions is a public concern. Arctic inhabitants are a high-risk group regarding health effects of environmental toxicants because of their high consumption of contaminated fish and wildlife. Developing fetuses and newborn infants may be particularly vulnerable to the effects of exposure to persistent organic pollutants (POPs) and toxic metals. Developmental exposure to environmental pollutants affects a wide range of clinical and biochemical parameters. Disturbance in skeletal growth, an integral component of somatic development, is a novel area in the toxicity of POPs. Low-dose prenatal exposure to TCDD caused a variety of harmful effects in rat long bones. In adult rats, TCDD exposure caused inhibited bone growth and lowered biomechanical properties of tibia and exposure to the dioxin-like PCBcongener 3,3,4,4,5-pentachlorobiphenyl has been associated with a decreased strength and collagen concentration of humerus. The aim of this study was to investigate effects of perinatal exposure to a mixture of PCBs, organochlorines and methyl mercury based on blood levels of Canadian Arctic populations on skeletal development in rat pups.

Analysis of environmental dispersion in a wetland flow under the effect of wind: Extended solution

Science.gov (United States)

Wang, Huilin; Huai, Wenxin

2018-02-01

The accurate analysis of the contaminant transport process in wetland flows is essential for environmental assessment. However, dispersivity assessment becomes complicated when the wind strength and direction are taken into consideration. Prior studies illustrating the wind effect on environmental dispersion in wetland flows simply focused on the mean longitudinal concentration distribution. Moreover, the results obtained by these analyses are not accurate when done on a smaller scale, namely, the initial stage of the contaminant transport process. By combining the concentration moments method (the Aris' method) and Gill's expansion theory, the previous researches on environmental dispersion in wetland flows with effect of wind have been extended. By adopting up to 4th-order moments, the wind effect-as illustrated by dimensionless parameters Er (wind force) and ω (wind direction)-on kurtosis and skewness is discussed, the up to 4th-order vertical concentration distribution is obtained, and the two-dimensional concentration distribution is illustrated. This work demonstrates that wind intensity and direction can significantly affect the contaminant dispersion. Moreover, the study presents a more accurate analytical solution of environmental dispersion in wetland flows under various wind conditions.

Copper Contamination Impairs Herbivore Initiation of Seaweed Inducible Defenses and Decreases Their Effectiveness.

Directory of Open Access Journals (Sweden)

Alexandria M Warneke

Full Text Available Seaweed-herbivore interactions are often mediated by environmental conditions, yet the roles of emerging anthropogenic stressors on these interactions are poorly understood. For example, chemical contaminants have unknown consequences on seaweed inducible resistance and herbivore response to these defenses despite known deleterious effects of contaminants on animal inducible defenses. Here, we investigated the effect of copper contamination on the interactions between a snail herbivore and a brown seaweed that displays inducible resistance to grazing. We examined seaweed inducible resistance and its effectiveness for organisms exposed to copper at two time points, either during induction or after herbivores had already induced seaweed defenses. Under ambient conditions, non-grazed tissues were more palatable than grazed tissues. However, copper additions negated the preference for non-grazed tissues regardless of the timing of copper exposure, suggesting that copper decreased both how herbivores initiated these inducible defenses and their subsequent effectiveness. Copper decreased stimulation of defenses, at least in part, by suppressing snail grazing pressure-the cue that turns inducible defenses on. Copper decreased effectiveness of defenses by preventing snails from preferentially consuming non-grazed seaweed. Thus, contaminants can potentially stress communities by changing seaweed-herbivore interactions mediated via inducible defenses. Given the ubiquity of seaweed inducible resistance and their potential influence on herbivores, we hypothesize that copper contamination may change the impact of these resistant traits on herbivores.

Listeriosis Outbreaks in British Columbia, Canada, Caused by Soft Ripened Cheese Contaminated from Environmental Sources

Science.gov (United States)

Wilcott, Lynn; Naus, Monika

2015-01-01

Soft ripened cheese (SRC) caused over 130 foodborne illnesses in British Columbia (BC), Canada, during two separate listeriosis outbreaks. Multiple agencies investigated the events that lead to cheese contamination with Listeria monocytogenes (L.m.), an environmentally ubiquitous foodborne pathogen. In both outbreaks pasteurized milk and the pasteurization process were ruled out as sources of contamination. In outbreak A, environmental transmission of L.m. likely occurred from farm animals to personnel to culture solutions used during cheese production. In outbreak B, birds were identified as likely contaminating the dairy plant's water supply and cheese during the curd-washing step. Issues noted during outbreak A included the risks of operating a dairy plant in a farm environment, potential for transfer of L.m. from the farm environment to the plant via shared toilet facilities, failure to clean and sanitize culture spray bottles, and cross-contamination during cheese aging. L.m. contamination in outbreak B was traced to wild swallows defecating in the plant's open cistern water reservoir and a multibarrier failure in the water disinfection system. These outbreaks led to enhanced inspection and surveillance of cheese plants, test and release programs for all SRC manufactured in BC, improvements in plant design and prevention programs, and reduced listeriosis incidence. PMID:25918702

Listeriosis Outbreaks in British Columbia, Canada, Caused by Soft Ripened Cheese Contaminated from Environmental Sources

Directory of Open Access Journals (Sweden)

Lorraine McIntyre

2015-01-01

Full Text Available Soft ripened cheese (SRC caused over 130 foodborne illnesses in British Columbia (BC, Canada, during two separate listeriosis outbreaks. Multiple agencies investigated the events that lead to cheese contamination with Listeria monocytogenes (L.m., an environmentally ubiquitous foodborne pathogen. In both outbreaks pasteurized milk and the pasteurization process were ruled out as sources of contamination. In outbreak A, environmental transmission of L.m. likely occurred from farm animals to personnel to culture solutions used during cheese production. In outbreak B, birds were identified as likely contaminating the dairy plant’s water supply and cheese during the curd-washing step. Issues noted during outbreak A included the risks of operating a dairy plant in a farm environment, potential for transfer of L.m. from the farm environment to the plant via shared toilet facilities, failure to clean and sanitize culture spray bottles, and cross-contamination during cheese aging. L.m. contamination in outbreak B was traced to wild swallows defecating in the plant’s open cistern water reservoir and a multibarrier failure in the water disinfection system. These outbreaks led to enhanced inspection and surveillance of cheese plants, test and release programs for all SRC manufactured in BC, improvements in plant design and prevention programs, and reduced listeriosis incidence.

Protective effect of Hongxue tea mixture against radiation injury in mice

International Nuclear Information System (INIS)

Zhao Chun; Zhang Xuehui; Wang Qi

2005-01-01

Objective: To develop health food of anti-radiation among biological source in Yunnan. Methods: Screening test was done of the health food of biological source of anti-radiation injury in mice. It is indicated that Hong-Xue Tea Mixture among the biological source has the effect against radiation injury, observing experiment of dose-effect of Hong-Xue Tea Mixture was done. Micronuclei in the bone marrow polychromatophilic erythrocytes in each dose group of mice were examined, leucocytes number and 30 day survival rate of mice following whole-body 5.0 Gy γ irradiation were also determined. Results: Research showed that Hong-Xue Tea Mixture and Spirulina Platensis Mixture among the biological source have protective effect against radiation injury in mice. Observing experiment of dose-effect of Hong-Xue Tea Mixture show that low, medium and high dose of Hong-Xue Tea Mixture can significantly decrease bone marrow PECMN rate of mice, increase leucocytes number and 30 day survival rate. Conclusion: Hong-Xue Tea Mixture has potent protective effects against radiation injury in mice. (authors)

Characterization of Under-Building Contamination at Rocky Flats Implementing Environmental-Measurement While Drilling Process with Horizontal Directional Drilling

International Nuclear Information System (INIS)

WILLIAMS, CECELIA V.; LOCKWOOD, GRANT J.; NORMANN, RANDY A.; LINDSAY, THOMAS

2001-01-01

Characterization is required on thirty-one buildings at Rocky Flats Environmental Technology Site (RFETS or the Site) with known or suspected under building contamination. The Site has teamed with Sandia National Laboratory (SNL) to deploy Environmental Measure-While-Drilling (EMWD) in conjunction with horizontal directional drilling (HDD) to characterize under building contamination and to evaluate the performance and applicability for future characterization efforts. The Environmental Measurement-While-Drilling-Gamma Ray Spectrometer (EMWD-GRS) system represents an innovative blend of new and existing technology that provides the capability of producing real-time environmental drill bit data during drilling operations. The project investigated two locations, Building 886 and Building 123. Building 886 is currently undergoing D and D activities. Building 123 was demolished in 1998; however, the slab is present with under building process waste lines and utilities. This report presents the results of the EMWD Gamma Ray Spectrometer logging of boreholes at these two sites. No gamma emitting contamination was detected at either location.(author)

Radon as an indicator of environmental contamination by hydrocarbons in free-phase

International Nuclear Information System (INIS)

Mateus, Crislene

2016-01-01

Contaminated sites by NAPL (Non-Aqueous Phase-Liquids) may lead to safety risks to human health and to ecosystems, restrictions to urban development and decrease of real estate value. This work used the radon gas as an indicator for the analysis of subsurface soil gas, once this noble gas presents good solubility in a wide range of NAPL, being partially retained in the NAPL contamination. Therefore, a decrease of the activity of radon in the contaminated soil gas can be expected, due to the high capacity of partitioning of radon in NAPL, which allows that the NAPL retain part of the radon previously available in the soil pores. The survey was carried out at a disused industry, contaminated by low volatile NAPL, located at southeast of Sao Paulo city, from June/14 to May/15. Radon was evaluated by passive detection methodology with CR-39 solid state nuclear track detectors (SSNTD) in ten monitoring stations installed in the contaminated area investigated and named 'A' to 'J'. Radon concentrations average for the eight monitoring stations at non-contaminated locations varied from (22 ± 4) kBq.m -3 to (39 ± 4) kBq.m -3 . For the two monitoring stations assumed as contaminated locations, radon concentrations average were (1.4 ± 0.4) kBq.m -3 and (13 ± 9) kBq.m -3 . The results have shown good agreement between the used method and the conventional environmental investigation techniques, for the majority of the monitoring stations in different seasons. Results obtained with CR-39 detectors varied over the exposure time due to the different seasons. No relation was observed between radon activity concentrations and rain volume accumulated over the different CR-39 exposure times. The lowest 222 Rn activity concentrations occurred in 'G' and 'H' monitoring stations, also verifying by gamma-ray spectrometry, that the low activities are not related to the activity concentration of its father 226 Ra from the 238 U decay chain

Anchoring novel molecular biomarker responses to traditional responses in fish exposed to environmental contamination

International Nuclear Information System (INIS)

Nogueira, Patricia; Pacheco, Mario; Lourdes Pereira, M.; Mendo, Sonia; Rotchell, Jeanette M.

2010-01-01

The responses of Dicentrarchus labrax and Liza aurata to aquatic pollution were assessed in a contaminated coastal lagoon, using both traditional and novel biomarkers combined. DNA damage, assessed by comet assay, was higher in both fish species from the contaminated sites, whereas levels of cytochrome P450 1A1 gene expression were not significantly altered. The liver histopathological analysis also revealed significant lesions in fish from contaminated sites. Alterations in ras and xpf genes were analysed and additional pollutant-responsive genes were identified. While no alterations were found in ras gene, a downregulation of xpf gene was observed in D. labrax from a contaminated site. Suppression subtractive hybridization applied to D. labrax collected at a contaminated site, revealed altered expression in genes involved in energy metabolism, immune system activity and antioxidant response. The approach and results reported herein demonstrate the utility of anchoring traditional biomarker responses alongside novel biomarker responses. - Novel molecular biomarkers of aquatic environmental contamination in fish.