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Sample records for block environmental toxic

  1. Environmental toxicants in developing countries.

    Science.gov (United States)

    Ostrosky-Wegman, P; Gonsebatt, M E

    1996-05-01

    Health effects from environmental toxicants may be a more serious problem in developing countries compared with developed countries because the problem is potentiated by other factors: a) the lack of or failure to enforce regulations, which allows human exposures to genotoxic agents; b) undernourishment of the lower economic and social classes that comprise the most exposed populations from industrial and agricultural activities; and c) parasitic infections that afflict a wide range of populations in both urban and rural areas. Data on the genotoxic effects of different types of exposures, including environmental exposes (natural and industrial), occupational exposures, and infections and medical treatments, are presented and discussed with the point of view that all these factors must be taken into account with respect to regulation and the protection of human health. Occupational exposures in developing countries are higher than in developed countries due to lack of stringent regulations, lack of knowledge of the risks involved, and the negligence of workers. General pollution is another important issue since developed countries have established strict regulations and risky industrial processes are being exported to developing countries, along with banned substances and dangerous industrial wastes. It should be emphasized that stringent regulations in developed countries will not prevent exposures in the long term because toxic substances that are released into the environment will ultimately reach all our future generations.

  2. Determinants of Toxicity of Environmental Asbestos Fibers

    Science.gov (United States)

    Recent EPA-led studies have addressed the comparative toxicity and pathological mechanisms of environmental asbestos samples from Libby, Montana and other communities in the United States. Longer amosite fibers induce a 4-10 fold greater induction of pro-inflammatory mediators C...

  3. Environmental Justice (EJSCREEN) Block Group Data (USEPA)

    Data.gov (United States)

    U.S. Environmental Protection Agency — EJSCREEN is an environmental justice (EJ) screening and mapping tool that provides EPA with a nationally consistent dataset and methodology for calculating "EJ...

  4. Hydroquinone: Environmental Pollution, Toxicity, and Microbial Answers

    Science.gov (United States)

    Leitão, Ana Lúcia

    2013-01-01

    Hydroquinone is a major benzene metabolite, which is a well-known haematotoxic and carcinogenic agent associated with malignancy in occupational environments. Human exposure to hydroquinone can occur by dietary, occupational, and environmental sources. In the environment, hydroquinone showed increased toxicity for aquatic organisms, being less harmful for bacteria and fungi. Recent pieces of evidence showed that hydroquinone is able to enhance carcinogenic risk by generating DNA damage and also to compromise the general immune responses which may contribute to the impaired triggering of the host immune reaction. Hydroquinone bioremediation from natural and contaminated sources can be achieved by the use of a diverse group of microorganisms, ranging from bacteria to fungi, which harbor very complex enzymatic systems able to metabolize hydroquinone either under aerobic or anaerobic conditions. Due to the recent research development on hydroquinone, this review underscores not only the mechanisms of hydroquinone biotransformation and the role of microorganisms and their enzymes in this process, but also its toxicity. PMID:23936816

  5. Investigating the Toxicity and Environmental Fate of Graphene Nanomaterials

    Science.gov (United States)

    The Hersam Laboratory at Northwestern University works with the Center for Environmental Implications of Nanotechnology and the United States Environmental Protection Agency to study the toxicity and environmental fate of emergent nanomaterials, specifically carbon-based nanomate...

  6. Hydroquinone: Environmental Pollution, Toxicity, and Microbial Answers

    Directory of Open Access Journals (Sweden)

    Francisco J. Enguita

    2013-01-01

    Full Text Available Hydroquinone is a major benzene metabolite, which is a well-known haematotoxic and carcinogenic agent associated with malignancy in occupational environments. Human exposure to hydroquinone can occur by dietary, occupational, and environmental sources. In the environment, hydroquinone showed increased toxicity for aquatic organisms, being less harmful for bacteria and fungi. Recent pieces of evidence showed that hydroquinone is able to enhance carcinogenic risk by generating DNA damage and also to compromise the general immune responses which may contribute to the impaired triggering of the host immune reaction. Hydroquinone bioremediation from natural and contaminated sources can be achieved by the use of a diverse group of microorganisms, ranging from bacteria to fungi, which harbor very complex enzymatic systems able to metabolize hydroquinone either under aerobic or anaerobic conditions. Due to the recent research development on hydroquinone, this review underscores not only the mechanisms of hydroquinone biotransformation and the role of microorganisms and their enzymes in this process, but also its toxicity.

  7. Assaying environmental nickel toxicity using model nematodes.

    Directory of Open Access Journals (Sweden)

    David Rudel

    Full Text Available Although nickel exposure results in allergic reactions, respiratory conditions, and cancer in humans and rodents, the ramifications of excess nickel in the environment for animal and human health remain largely undescribed. Nickel and other cationic metals travel through waterways and bind to soils and sediments. To evaluate the potential toxic effects of nickel at environmental contaminant levels (8.9-7,600 µg Ni/g dry weight of sediment and 50-800 µg NiCl2/L of water, we conducted assays using two cosmopolitan nematodes, Caenorhabditis elegans and Pristionchus pacificus. We assayed the effects of both sediment-bound and aqueous nickel upon animal growth, developmental survival, lifespan, and fecundity. Uncontaminated sediments were collected from sites in the Midwestern United States and spiked with a range of nickel concentrations. We found that nickel-spiked sediment substantially impairs both survival from larval to adult stages and adult longevity in a concentration-dependent manner. Further, while aqueous nickel showed no adverse effects on either survivorship or longevity, we observed a significant decrease in fecundity, indicating that aqueous nickel could have a negative impact on nematode physiology. Intriguingly, C. elegans and P. pacificus exhibit similar, but not identical, responses to nickel exposure. Moreover, P. pacificus could be tested successfully in sediments inhospitable to C. elegans. Our results add to a growing body of literature documenting the impact of nickel on animal physiology, and suggest that environmental toxicological studies could gain an advantage by widening their repertoire of nematode species.

  8. Assaying environmental nickel toxicity using model nematodes

    Science.gov (United States)

    Rudel, David; Douglas, Chandler; Huffnagle, Ian; Besser, John M.; Ingersoll, Christopher G.

    2013-01-01

    Although nickel exposure results in allergic reactions, respiratory conditions, and cancer in humans and rodents, the ramifications of excess nickel in the environment for animal and human health remain largely undescribed. Nickel and other cationic metals travel through waterways and bind to soils and sediments. To evaluate the potential toxic effects of nickel at environmental contaminant levels (8.9-7,600 µg Ni/g dry weight of sediment and 50-800 µg NiCl2/L of water), we conducted assays using two cosmopolitan nematodes, Caenorhabditis elegans and Pristionchus pacificus. We assayed the effects of both sediment-bound and aqueous nickel upon animal growth, developmental survival, lifespan, and fecundity. Uncontaminated sediments were collected from sites in the Midwestern United States and spiked with a range of nickel concentrations. We found that nickel-spiked sediment substantially impairs both survival from larval to adult stages and adult longevity in a concentration-dependent manner. Further, while aqueous nickel showed no adverse effects on either survivorship or longevity, we observed a significant decrease in fecundity, indicating that aqueous nickel could have a negative impact on nematode physiology. Intriguingly, C. elegansand P. pacificus exhibit similar, but not identical, responses to nickel exposure. Moreover, P. pacificus could be tested successfully in sediments inhospitable to C. elegans. Our results add to a growing body of literature documenting the impact of nickel on animal physiology, and suggest that environmental toxicological studies could gain an advantage by widening their repertoire of nematode species.

  9. Environmental air toxics: role in asthma occurrence?

    OpenAIRE

    Larsen, Gary L.; Beskid, Craig; Shirnamé-Moré, Lata

    2002-01-01

    The National Urban Air Toxics Research Center (NUATRC) hosted its first scientific workshop in 1994 that focused on possible relationships between air toxics and asthma. From that meeting came recommendations for future research including a need for more complete individual personal exposure assessments so that determinations of personal exposures to pollutants could be made. In the spring of 2001, NUATRC held a second such workshop to review progress made in this area during the intervening ...

  10. Prenatal imprinting by environmental toxicants: really an important issue?

    Directory of Open Access Journals (Sweden)

    Karl Ernst v. Mühlendahl

    2015-06-01

    Full Text Available Prenatal imprinting of sexual behaviour and of other traits by environmental toxicants has been one important topic in the ongoing discussions in environmental medicine. This review of the literature shows that, so far, concrete data are sparse and, in part, contradictory.

  11. Thermoregulatory responses to environmental toxicants: the interaction of thermal stress and toxicant exposure.

    Science.gov (United States)

    Leon, Lisa R

    2008-11-15

    Thermal stress can have a profound impact on the physiological responses that are elicited following environmental toxicant exposure. The efficacy by which toxicants enter the body is directly influenced by thermoregulatory effector responses that are evoked in response to high ambient temperatures. In mammals, the thermoregulatory response to heat stress consists of an increase in skin blood flow and moistening of the skin surface to dissipate core heat to the environment. These physiological responses may exacerbate chemical toxicity due to increased permeability of the skin, which facilitates the cutaneous absorption of many environmental toxicants. The core temperature responses that are elicited in response to high ambient temperatures, toxicant exposure or both can also have a profound impact on the ability of an organism to survive the insult. In small rodents, the thermoregulatory response to thermal stress and many environmental toxicants (such as organophosphate compounds) is often biphasic in nature, consisting initially of a regulated reduction in core temperature (i.e., hypothermia) followed by fever. Hypothermia is an important thermoregulatory survival strategy that is used by small rodents to diminish the effect of severe environmental insults on tissue homeostasis. The protective effect of hypothermia is realized by its effects on chemical toxicity as molecular and cellular processes, such as lipid peroxidation and the formation of reactive oxygen species, are minimized at reduced core temperatures. The beneficial effects of fever are unknown under these conditions. Perspective is provided on the applicability of data obtained in rodent models to the human condition.

  12. Enrichment with wood blocks does not affect toxicity assessment in an exploratory toxicology model using Sprague-Dawley rats.

    Science.gov (United States)

    Ditewig, Amy C; Bratcher, Natalie A; Davila, Donna R; Dayton, Brian D; Ebert, Paige; Lesuisse, Philippe; Liguori, Michael J; Wetter, Jill M; Yang, Hyuna; Buck, Wayne R

    2014-05-01

    Environmental enrichment in rodents may improve animal well-being but can affect neurologic development, immune system function, and aging. We tested the hypothesis that wood block enrichment affects the interpretation of traditional and transcriptomic endpoints in an exploratory toxicology testing model using a well-characterized reference compound, cyclophosphamide. ANOVA was performed to distinguish effects of wood block enrichment separate from effects of 40 mg/kg cyclophosphamide treatment. Biologically relevant and statistically significant effects of wood block enrichment occurred only for body weight gain. ANOVA demonstrated the expected effects of cyclophosphamide on food consumption, spleen weight, and hematology. According to transcriptomic endpoints, cyclophosphamide induced fewer changes in gene expression in liver than in spleen. Splenic transcriptomic pathways affected by cyclophosphamide included: iron hemostasis; vascular tissue angiotensin system; hepatic stellate cell activation and fibrosis; complement activation; TGFβ-induced hypertrophy and fibrosis; monocytes, macrophages, and atherosclerosis; and platelet activation. Changes in these pathways due to cyclophosphamide treatment were consistent with bone marrow toxicity regardless of enrichment. In a second study, neither enrichment nor type of cage flooring altered body weight or food consumption over a 28-d period after the first week. In conclusion, wood block enrichment did not interfere with a typical exploratory toxicology study; the effects of ingested wood on drug level kinetics may require further consideration.

  13. POTENTIAL CELL LINE TOXICITY OF ENVIRONMENTAL NANOPARTICLES

    Directory of Open Access Journals (Sweden)

    Mohan Durga

    2012-01-01

    Full Text Available In India, the unprecedented growth rate and urbanization along with the rapid increase in motor vehicle activity and industrialization are contributing to high levels of urban air pollution. The population is mainly exposed to high air pollution concentrations, where motor vehicle emissions constitute the main source of fine and ultrafine particles. Motor exhaust emissions is a mixture of gases and Particulate Matter (PM. Diesel and petrol fuels in vehicles produce combustion-derived particles as a result of combustion. Vehicle exhaust particles are the main constituents of environmental nanoparticles. In the present investigation, environmental nanoparticles such as Diesel Exhaust Particles (DEP and Petrol Exhaust Particles (PEP were collected from on-road vehicles using a specially designed collection chamber. The surface morphology of the collected particles was analyzed through Transmission Electron Microscope (TEM, and the elemental mapping was performed through EDAX analysis. Results indicated the presence of nanometer-size particles in both the categories of vehicle exhaust. These small-size particles of respirable range can enter the respiratory tract of humans and get deposited in the lungs and cause various effects inside the human body. The aim of this study is to assess the cytotoxicity of the collected Diesel Exhaust Nanoparticles (DENPs and Petrol Exhaust Nanoparticles (PENPs. Cytotoxicity endpoint, such as IC50 (50% Inhibitory Concentration, was determined after a 24-h exposure. Results of this study indicated that all five cell lines were sensitive to these vehicle exhaust nanoparticles at varying levels.

  14. Local anaesthetic toxicity after bilateral thoracic paravertebral block in patients undergoing coronary artery bypass surgery.

    Science.gov (United States)

    Ho, A M-H; Karmakar, M K; Ng, S K; Wan, S; Ng, C S H; Wong, R H L; Chan, S K C; Joynt, G M

    2016-09-01

    We conducted a small pilot observational study of the effects of bilateral thoracic paravertebral block (BTPB) as an adjunct to perioperative analgesia in coronary artery bypass surgery patients. The initial ropivacaine dose prior to induction of general anaesthesia was 3 mg/kg, which was followed at the end of the surgery by infusion of ropivacaine 0.25% 0.1 ml/kg/hour on each side (e.g. total 35 mg/hour for a 70 kg person). The BTPB did not eliminate the need for supplemental opioids after CABG in the eight patients studied. Moreover, in spite of boluses that were within the manufacturer's recommendation for epidural and major nerve blocks, and an infusion rate that was only slightly higher than what appeared to be safe for epidural infusion, potentially toxic total plasma ropivacaine concentrations were common. We also could not exclude the possibility that the high ropivacaine concentrations were contributing to postoperative mental state changes in the postoperative period. Also, one patient developed local anaesthetic toxicity after the bilateral paravertebral dose. As a result, the study was terminated early after four days. The question of whether paravertebral block confers benefits in cardiac surgery remains unanswered. However, we believe that the bolus dosage and the injection rate we used for BTPB were both too high, and caution other clinicians against the use of these doses. Future studies on the use of BTPB in cardiac surgery patients should include reduced ropivacaine doses injected over longer periods.

  15. Animal models of peripheral neuropathy due to environmental toxicants.

    Science.gov (United States)

    Rao, Deepa B; Jortner, Bernard S; Sills, Robert C

    2014-01-01

    Despite the progress in our understanding of pathogeneses and the identification of etiologies of peripheral neuropathy, idiopathic neuropathy remains common. Typically, attention to peripheral neuropathies resulting from exposure to environmental agents is limited relative to more commonly diagnosed causes of peripheral neuropathy (diabetes and chemotherapeutic agents). Given that there are more than 80,000 chemicals in commerce registered with the Environmental Protection Agency and that at least 1000 chemicals are known to have neurotoxic potential, very few chemicals have been established to affect the peripheral nervous system (mainly after occupational exposures). A wide spectrum of exposures, including pesticides, metals, solvents, nutritional sources, and pharmaceutical agents, has been related, both historically and recently, to environmental toxicant-induced peripheral neuropathy. A review of the literature shows that the toxicity and pathogeneses of chemicals adversely affecting the peripheral nervous system have been studied using animal models. This article includes an overview of five prototypical environmental agents known to cause peripheral neuropathy--namely, organophosphates, carbon disulfide, pyridoxine (Vitamin B6), acrylamide, and hexacarbons (mainly n-hexane, 2,5-hexanedione, methyl n-butyl ketone). Also included is a brief introduction to the structural components of the peripheral nervous system and pointers on common methodologies for histopathologic evaluation of the peripheral nerves.

  16. Environmental Justice (EJSCREEN) Block Group Data (USEPA) for 2016

    Data.gov (United States)

    U.S. Environmental Protection Agency — EJSCREEN is an environmental justice (EJ) screening and mapping tool that provides EPA with a nationally consistent dataset and methodology for calculating "EJ...

  17. Potential Environmental Justice Areas - (EJSCREEN) Block Group Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — These data are from EJSCREEN, an environmental justice (EJ) screening and mapping tool that provides EPA with a nationally consistent dataset and methodology for...

  18. Environmental lead toxicity: Nutrition as a component of intervention

    Energy Technology Data Exchange (ETDEWEB)

    Mahaffey, K.R. (National Institute of Environmental Health Sciences, Research Triangle Park, NC (USA))

    1990-11-01

    The influence of nutritional status on susceptibility to the toxicity of lead is discussed. Emphasis is given to dietary factors of substantial clinical importance. Subtle changes in susceptibility are difficult to evaluate under conditions of overwhelming lead exposure. It is clear that subtle effects of lead exposure on neurobehavioral and cognitive development are a major concern. The role of nutrition is considered to be an adjunct to reduction of environmental lead exposure, which is the primary means of reducing adverse health effects of lead. Nutrition should be evaluated as a component of strategies to address this broad societal issue.

  19. Environmental behavior and toxicity of herbicides atrazine and simazine

    Directory of Open Access Journals (Sweden)

    Ana Paula Barbosa do Carmo

    2013-04-01

    Full Text Available This article shows some environmental and toxicology aspects of triazine herbicides atrazine and simazine. These compounds are used to control weeds in sugar and corn crops. Despite being partially soluble, they can be detected in ground and surface water. Their mobility and biodegradation in the soil-water system can vary depending on the intrinsic characteristics of each matrice, such as organic matter content. Although considered slightly toxic, these herbicides have a strong ability to interfere in the nervous and endocrine systems of human and wild biota. The detoxification mechanisms are similar to other xenobiotics; however, little is known about the effects on human health caused by simazine. Therefore, the use of these compounds should be revised due to their environmental behavior and toxicological effects.

  20. Studies on polymer-coated zinc oxide nanoparticles: UV-blocking efficacy and in vivo toxicity.

    Science.gov (United States)

    Girigoswami, Koyeli; Viswanathan, Meenakshi; Murugesan, Ramachandran; Girigoswami, Agnishwar

    2015-11-01

    Zinc oxide (ZnO) is explicitly used in sunscreens and cosmetic products; however, its effect in vivo is toxic in some cases. The UV blocking efficacy of ZnO nanoparticles is lost due to photocatalysis. To isolate a lower toxic species of sunblockers, ZnO nanoparticles were synthesized and coated with chitosan - a natural polymer (ZnO-CTS) and polyethylene glycol (PEG) - a synthetic polymer (ZnO-PEG). Coating with CTS and PEG circumvented the photocatalytic activity, increased the stability and improved the UV absorption efficacy. The effect of ZnO, ZnO-CTS and ZnO-PEG nanoparticles in vivo on zebrafish embryo revealed lower deposition of ZnO-CTS and ZnO-PEG nanoparticles atop the eggs compared to ZnO. The survival of zebrafish embryos was always found to be higher in case of ZnO-CTS with respect to ZnO-treated ones. PEG coating exhibited better UV attenuation, but, in vivo it induced delayed hatching. Thus, one of the reasons for better survival could be attributed to lower aggregation of ZnO-CTS nanoparticles atop eggs thereby facilitating the breathing of embryos.

  1. Environmental toxicity and radioactivity assessment of a titanium-processing residue with potential for environmental use.

    Science.gov (United States)

    Wendling, Laura A; Binet, Monique T; Yuan, Zheng; Gissi, Francesca; Koppel, Darren J; Adams, Merrin S

    2013-07-01

    Thorough examination of the physicochemical characteristics of a Ti-processing residue was undertaken, including mineralogical, geochemical, and radiochemical characterization, and an investigation of the environmental toxicity of soft-water leachate generated from the residue. Concentrations of most metals measured in the leachate were low; thus, the residue is unlikely to leach high levels of potentially toxic elements on exposure to low-ionic strength natural waters. Relative to stringent ecosystem health-based guidelines, only chromium concentrations in the leachate exceeded guideline concentrations for 95% species protection; however, sulfate was present at concentrations known to cause toxicity. It is likely that the high concentration of calcium and extreme water hardness of the leachate reduced the bioavailability of some elements. Geochemical modeling of the leachate indicated that calcium and sulfate concentrations were largely controlled by gypsum mineral dissolution. The leachate was not toxic to the microalga Chlorella sp., the cladoceran Ceriodaphnia dubia, or the estuarine bacterium Vibrio fischeri. The Ti-processing residue exhibited an absorbed dose rate of 186 nGy/h, equivalent to an annual dose of 1.63 mGy and an annual effective dose of 0.326 mGy. In summary, the results indicate that the Ti-processing residue examined is suitable for productive use as an environmental amendment following 10 to 100 times dilution to ameliorate potential toxic effects due to chromium or sulfate.

  2. Bidding for blocks and environmental control; Licitacao de blocos e o controle ambiental

    Energy Technology Data Exchange (ETDEWEB)

    Agostinho, Magila Maria [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Faculdade de Direito; Silveira Neto, Otacilio dos Santos [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Programa de Recursos Humanos da ANP em Direito do Petroleo e Gas Natural, PRH-36

    2004-07-01

    With the coming of the Constitutional Emend n. 9/95, the Brazilian market of oil and natural gas stopped being monopolized by PETROBRAS. Since then, the concession of blocks began to be preceded by the public tender procedure realized by ANP- National Agency of Oil. The activities of oil exploration and production are potentially damaging to environment, what brings necessary the environmental licence and the previous study of the environmental impacts caused in this activity. Considering that the environmental licence must be done after the tender process, the enterprises that bought the blocks would assume the risk of not being allowed to practice their activities because of the absence of the environmental licence. To avoid that the It's offered blocks in not viable areas for oil exploration, the ANP, responsible for the public tender must accomplish a previous environmental control, to assure to the enterprises involved the environmental viability of the blocks offered. This project will touch the question of how has been realized the previous environmental control of the blocks offered by ANP into the public tender process, detaching, the control done at the 6. Round. (author)

  3. Vicia faba bioassay for environmental toxicity monitoring: A review.

    Science.gov (United States)

    Iqbal, Munawar

    2016-02-01

    Higher plants are recognized as excellent genetic models to detect cytogenetic and mutagenic agents and are frequently used in environmental monitoring studies. Vicia faba (V. faba) bioassay have been used to study DNA damages i.e., chromosomal and nuclear aberrations induced by metallic compounds, pesticides, complex mixtures, petroleum derivates, toxins, nanoparticles and industrial effluents. The main advantages of using V. faba is its availability round the year, economical to use, easy to grow and handle; its use does not require sterile conditions, rate of cell division is fast, chromosomes are easy to score, less expensive and more sensitive as compared to other short-term tests that require pre-preparations. The V. faba test offers evaluation of different endpoints and tested agents can be classified as cytotoxic/genotoxic/mutagenic. This test also provides understanding about mechanism of action, whether the tested agent is clastogenic or aneugenic in nature. In view of advantages offered by V. faba test system, it is used extensively to assess toxic agents and has been emerged as an important bioassay for ecotoxicological studies. Based on the applications of V. faba test to assess the environmental quality, this article offers an overview of this test system and its efficiency in assessing the cytogenetic and mutagenic agents in different classes of the environmental concerns.

  4. Vitamin D toxicity presenting as hypercalcemia and complete heart block: An interesting case report

    Directory of Open Access Journals (Sweden)

    G Garg

    2012-01-01

    Full Text Available Vitamin D deficiency is widely prevalent across the globe. This has lead to widespread use of vitamin D supplements in populations. We present our experience of vitamin D toxicity in a subject resulting in hypercalcemia and CHB (Complete Heart Block. A 70-year-old female, known hypertensive for thirty five years and diabetic for seven years underwent total knee replacement (TKR for osteoarthritis left knee in December 2010. For perioperative glycemic control, multiple subcutaneous injections of insulin were advised. Patient later presented with poor glycemic control, decreased appetite and constipation for last 1 month with history of episodes of transient loss of consciousness for 15 days and recurrent vomiting. Biochemical work-up showed hypercalcemia (Serum calcium 12.4 mg/dL. Sr. albumin, ALP, Sr. phosphorus and PTH levels were normal, thus suggesting PTH independent hypercalcemia. Strong suspicion led us to check vitamin D levels in dilution which were 2016 ng/mL, thus confirming vitamin D toxicity. Retrospective analysis of treatment history revealed patient receiving 4 injections of Architol (6 Lac units im prior to presentation. Work-up for malignancy was negative, brain imaging and EEG were normal. Holter was suggestive of intermittent CHB. Patient was given hydration, injection calcitonin 100 I.U. subcutaneously, injection pamidronate 60 mg infusion, with serum calcium levels normalizing, with relief in constipation, vomiting and behavioral improvement. However, persistence of rhythm disturbances led to permanent pacemaker placement. The present case highlights the dangers of indiscriminate vitamin D usage, exposing patients to potentially life threatening complications.

  5. Environmental toxicants-induced immune responses in the olfactory mucosa

    Directory of Open Access Journals (Sweden)

    Fumiaki Imamura

    2016-11-01

    Full Text Available Olfactory sensory neurons (OSNs are the receptor cells for the sense of smell. Although cell bodies are located in the olfactory mucosa of the nasal cavity, OSN axons directly project to the olfactory bulb that is a component of the central nervous system (CNS. Because of this direct and short connection from this peripheral tissue to the CNS, the olfactory system has attracted attention as a port-of-entry for environmental toxicants that may cause neurological dysfunction. Selected viruses can enter the olfactory bulb via the olfactory mucosa, and directly affect the CNS. On the other hand, environmental toxicants may induce inflammatory responses in the olfactory mucosa, including infiltration of immune cells and production of inflammatory cytokines. In addition, these inflammatory responses cause the loss of OSNs that are then replaced with newly generated OSNs that re-connect to the olfactory bulb after inflammation has subsided. It is now known that immune cells and cytokines in the olfactory mucosa play important roles in both degeneration and regeneration of OSNs. Thus, the olfactory system is a unique neuroimmune interface where interaction between nervous and immune systems in the periphery significantly affects the structure, neuronal circuitry, and immunological status of the CNS. The mechanisms by which immune cells regulate OSN loss and the generation of new OSNs are, however, largely unknown. To help develop a better understanding of the mechanisms involved, we have provided a review of key research that has investigated how the immune response in the olfactory mucosa affects the pathophysiology of OSNs.

  6. The neuronal nitric oxide synthase inhibitor NANT blocks acetaminophen toxicity and protein nitration in freshly isolated hepatocytes.

    Science.gov (United States)

    Banerjee, Sudip; Melnyk, Stepan B; Krager, Kimberly J; Aykin-Burns, Nukhet; Letzig, Lynda G; James, Laura P; Hinson, Jack A

    2015-12-01

    3-Nitrotyrosine (3NT) in liver proteins of mice treated with hepatotoxic doses of acetaminophen (APAP) has been postulated to be causative in toxicity. Nitration is by a reactive nitrogen species formed from nitric oxide (NO). The source of the NO is unclear. iNOS knockout mice were previously found to be equally susceptible to APAP toxicity as wildtype mice and iNOS inhibitors did not decrease toxicity in mice or in hepatocytes. In this work we examined the potential role of nNOS in APAP toxicity in hepatocytes using the specific nNOS inhibitor NANT (10 µM)(N-[(4S)-4-amino-5-[(2-aminoethyl)amino]pentyl]-N'-nitroguanidinetris (trifluoroacetate)). Primary hepatocytes (1 million/ml) from male B6C3F1 mice were incubated with APAP (1mM). Cells were removed and assayed spectrofluorometrically for reactive nitrogen and oxygen species using diaminofluorescein (DAF) and Mitosox red, respectively. Cytotoxicity was determined by LDH release into media. Glutathione (GSH, GSSG), 3NT, GSNO, acetaminophen-cysteine adducts, NAD, and NADH were measured by HPLC. APAP significantly increased cytotoxicity at 1.5-3.0 h. The increase was blocked by NANT. NANT did not alter APAP mediated GSH depletion or acetaminophen-cysteine adducts in proteins which indicated that NANT did not inhibit metabolism. APAP significantly increased spectroflurometric evidence of reactive nitrogen and oxygen formation at 0.5 and 1.0 h, respectively, and increased 3NT and GSNO at 1.5-3.0 h. These increases were blocked by NANT. APAP dramatically increased NADH from 0.5-3.0 h and this increase was blocked by NANT. Also, APAP decreased the Oxygen Consumption Rate (OCR), decreased ATP production, and caused a loss of mitochondrial membrane potential, which were all blocked by NANT.

  7. Drinking water toxicity study of the environmental contaminant--Bromate.

    Science.gov (United States)

    Dongmei, Liu; Zhiwei, Wang; Qi, Zhu; Fuyi, Cui; Yujuan, Shan; Xiaodong, Liu

    2015-12-01

    Bromate is a byproduct of water disinfection that is produced when waters contain bromide treated with ozone. To investigate the level of the toxicity of bromate and find the most sensitive indicators in a short time, a series of toxicological assessments were conducted including the acute toxicity, cumulative toxicity, genetic toxicity and subacute toxicity of bromate (using Potassium Bromate to represent bromate). The LD50 of orally administered Potassium Bromate was 215 mg/kg in Wistar rats and 464 mg/kg in ICR mice. The cumulative toxicity of Potassium Bromate was not obvious. The Ames test, mouse bone marrow cell micronucleus test and mouse sperm abnormality test did not indicate mutagenicity. The results of the subacute study did not exhibit significant differences in most of the parameters, except the white blood cell count, which was significantly decreased in male rats. In addition, Potassium Bromate influenced the albumin, creatinine, total cholesterol, triglycerides and glucose levels in male rats to various extents. A thorough analysis of the above tests clearly demonstrates that bromate has toxicity, not obvious cumulative toxicity and the white blood cell count can be used as an indicator to reflect the toxicity of bromate and investigate bromate's toxic mechanism.

  8. Kinetics of zinc toxicity to environmental bacterial isolates

    Directory of Open Access Journals (Sweden)

    Christian Okechukwu Nweke

    2009-12-01

    Full Text Available Toxicity of zinc to Pseudomonas, Escherichia, Proteus, Bacillus and Arthrobacter species isolated from a tropical river and petroleum refinery effluent was assessed using TTC-dehydrogenase activity (DHA inhibition test. At sufficient concentrations, zinc is toxic to these bacterial cells, and the exposure of the cells to zinc ion resulted in repression of dehydrogenase activity. The patterns of these toxic effects can be mathematically described with logistic dose-response models and in a manner similar to the non-competitive inhibition of enzymes. The threshold concentration above which toxic effect is observed ranged from 0.008 mM for Pseudomonas sp. DAF1 to 0.364 mM for Proteus sp. PLK2. The coefficients of inhibition Ki correlated with the IC50 and indicate that zinc toxicity is dependent on the organism. The Ki and toxicity threshold values predicted from the equations are comparable and are suitable indicators for kinetic analyses of zinc toxicity against bacteria.

  9. Co-administration of N-Acetylcysteine and Acetaminophen Efficiently Blocks Acetaminophen Toxicity.

    Science.gov (United States)

    Owumi, Solomon E; Andrus, James P; Herzenberg, Leonard A; Herzenberg, Leonore A

    2015-08-01

    Preclinical Research Although acetaminophen (APAP) is an effective analgesic and anti-pyretic, APAP overdose is the most frequent cause of serious, often lethal, drug-induced hepatotoxicity. Administration of N-acetyl cysteine (NAC) within 8 hours of APAP overdose effectively mitigates APAP-induced hepatotoxicity. Thus, preventing APAP toxicity before it occurs by formulating APAP with NAC is logical and, as we show here in a mouse model, is effective in preventing APAP toxicity. Thus, toxic oral APAP doses sufficient to cause severe widespread liver damage do not cause significant damage when administered concurrently with equal amounts of NAC, that is, in the NAC-APAP treated animals, hepatic transaminases increase only marginally and liver architecture remains fully intact. Thus, we conclude that concomitant oral dosing with APAP and NAC can provide a convenient and effective way of preventing toxicity associated with large dosage of APAP. From a public health perspective, these findings support the concept that a co-formulation of APAP plus NAC is a viable over-the-counter (OTC) alternative to the current practice of providing APAP OTC and treating APAP toxicity if/when it occurs. In essence, our findings indicate that replacing the current OTC APAP with a safe and functional APAP/NAC formulation could prevent the accidental and intentional APAP toxicity that occurs today.

  10. Environmental properties of long chain alcohols. Part 1: Physicochemical, environmental fate and acute aquatic toxicity properties

    DEFF Research Database (Denmark)

    Fisk, Peter; Sanderson, Hans; Wildey, Ross;

    2009-01-01

    This paper summarises the physicochemical, biodegradation and acute aquatic ecotoxicity properties of long chain aliphatic alcohols. Properties of pure compounds are shown to follow somewhat predictable trends, which are amenable to estimation by quantitative structure-activity relationships ((Q......)SARs). This allows predictions of data relating to human and environmental safety profiles and patterns. These alcohols have been shown to be rapidly degradable under standard conditions up to C18. Furthermore, evidence suggests that longer chain lengths are also rapidly biodegradable. While log Kow values suggest...... possible bioaccumulation potential, available data suggest that these substances are not as bioaccumulative as estimations would predict. For acute aquatic toxicity, solubility limits the possibility of effects being appropriately observed and become increasingly challenging above C12. Further, a model has...

  11. ROLE OF ENVIRONMENTAL HEAT AND COLD STRESS ON THE PHYSIOLOGICAL RESPONSE TO ORGANOPHOSPHATES AND OTHER TOXICANTS.

    Science.gov (United States)

    Most toxicological and pharmacological studies are performed in laboratory rodents maintained under comfortable environmental conditions. However, exposure to toxicants as well as some drugs can occur under stressful conditions during rest or while exercising. Heat stress can exa...

  12. Molecular building blocks and their architecture in biologically/environmentally compatible soft matter chemical machinery.

    Science.gov (United States)

    Toyota, Taro; Banno, Taisuke; Nitta, Sachiko; Takinoue, Masahiro; Nomoto, Tomonori; Natsume, Yuno; Matsumura, Shuichi; Fujinami, Masanori

    2014-01-01

    This review briefly summarizes recent developments in the construction of biologically/environmentally compatible chemical machinery composed of soft matter. Since environmental and living systems are open systems, chemical machinery must continuously fulfill its functions not only through the influx and generation of molecules but also via the degradation and dissipation of molecules. If the degradation or dissipation of soft matter molecular building blocks and biomaterial molecules/polymers can be achieved, soft matter particles composed of them can be used to realize chemical machinery such as selfpropelled droplets, drug delivery carriers, tissue regeneration scaffolds, protocell models, cell-/tissuemarkers, and molecular computing systems.

  13. Evaluation of Environmental and Hydraulic Performance of Bio-Composite Revetment Blocks

    Directory of Open Access Journals (Sweden)

    Thamer A.  Ahmeed

    2006-01-01

    Full Text Available It is necessary to develop a concrete revetment block which can cater for environment and at the same time it will be effective in protecting river banks (stabilize the slope of banks from scouring during flood. In the present study, the environmental and hydraulic performance of the proposed revetment block was evaluated through laboratory and field tests. The tested revetment block is called bio-composite because it is composed of concrete, plastic mesh and biological material (coconut husk. The dimensions of the bio-composite revetment block are 400 mm x 400 mm x 100 mm (length x width x thickness and has a central opening with a dimensions of 280 mm x 140 mm that has a 10 mm layer of coconut husks protected by two layers of plastic mesh. The coconut husk was selected based on laboratory experiments. The experiments showed that the coconut husk is a good media for grass growth and it allows faster growth of grass compared with other tested types of biological wastes (sugar cane husk and oil palm husk. Field tests were conducted on a selected stream which is located at the Universiti Putra Malaysia, Selangor, Malaysia. The stream banks were protected from scouring by using the bio-composite blocks and monitoring after installation revealed that rate of grass growth was 15% per week. However, it was found that the rate of grass growth is depends on the slope of stream banks. This confirms that the proposed bio-composite block is friendly to the environment and can give a good aesthetic appearance. For a given water depth, hydraulic tests showed that the value of Manning coefficient of roughness for the bio-composite revetment blocks depends mainly on the rate of grass growth. The values of Manning coefficient roughness for the stream were found to range from 0.031 to 0.055.

  14. 77 FR 37678 - Board of Scientific Counselors, National Center for Environmental Health/Agency for Toxic...

    Science.gov (United States)

    2012-06-22

    ... HUMAN SERVICES Centers for Disease Control and Prevention Board of Scientific Counselors, National Center for Environmental Health/Agency for Toxic Substances and Disease Registry: Notice of Charter..., that the Board of Scientific Counselors, National Center for Environmental Health/Agency for...

  15. Predicting the risk of toxic blooms of golden alga from cell abundance and environmental covariates

    Science.gov (United States)

    Patino, Reynaldo; VanLandeghem, Matthew M.; Denny, Shawn

    2016-01-01

    Golden alga (Prymnesium parvum) is a toxic haptophyte that has caused considerable ecological damage to marine and inland aquatic ecosystems worldwide. Studies focused primarily on laboratory cultures have indicated that toxicity is poorly correlated with the abundance of golden alga cells. This relationship, however, has not been rigorously evaluated in the field where environmental conditions are much different. The ability to predict toxicity using readily measured environmental variables and golden alga abundance would allow managers rapid assessments of ichthyotoxicity potential without laboratory bioassay confirmation, which requires additional resources to accomplish. To assess the potential utility of these relationships, several a priori models relating lethal levels of golden alga ichthyotoxicity to golden alga abundance and environmental covariates were constructed. Model parameters were estimated using archived data from four river basins in Texas and New Mexico (Colorado, Brazos, Red, Pecos). Model predictive ability was quantified using cross-validation, sensitivity, and specificity, and the relative ranking of environmental covariate models was determined by Akaike Information Criterion values and Akaike weights. Overall, abundance was a generally good predictor of ichthyotoxicity as cross validation of golden alga abundance-only models ranged from ∼ 80% to ∼ 90% (leave-one-out cross-validation). Environmental covariates improved predictions, especially the ability to predict lethally toxic events (i.e., increased sensitivity), and top-ranked environmental covariate models differed among the four basins. These associations may be useful for monitoring as well as understanding the abiotic factors that influence toxicity during blooms.

  16. Metabonomics in the preclinical and environmental toxicity field.

    Science.gov (United States)

    Colet, Jean-Marie

    2015-06-01

    Preclinical studies assess both efficacy and safety of new drugs through a series of assays used to identify potential target organs and determine safety thresholds. However, despite these efforts, too many drugs prove toxic to humans during clinical phases or later on the market. This paper reviews how metabonomics, one of the key players in systems biology, should be able to assist toxicologists in better predicting the adverse effects of xenobiotics.

  17. Comparative developmental toxicity of environmentally relevant oxygenated PAHs

    Energy Technology Data Exchange (ETDEWEB)

    Knecht, Andrea L., E-mail: andrea.knecht@tanguaylab.com [Department of Environmental and Molecular Toxicology, the Environmental Health Sciences Center, Oregon State University, Corvallis, OR (United States); Goodale, Britton C., E-mail: goodaleb@onid.orst.edu [Department of Environmental and Molecular Toxicology, the Environmental Health Sciences Center, Oregon State University, Corvallis, OR (United States); Truong, Lisa, E-mail: lisa.truong.888@gmail.com [Department of Environmental and Molecular Toxicology, the Environmental Health Sciences Center, Oregon State University, Corvallis, OR (United States); Simonich, Michael T., E-mail: mtsimonich@oregonstate.edu [Department of Environmental and Molecular Toxicology, the Environmental Health Sciences Center, Oregon State University, Corvallis, OR (United States); Swanson, Annika J., E-mail: swansoan@onid.orst.edu [Department of Environmental and Molecular Toxicology, the Environmental Health Sciences Center, Oregon State University, Corvallis, OR (United States); Matzke, Melissa M., E-mail: melissa.matzke@pnl.gov [Computational Biology and Bioinformatics, Pacific Northwest National Laboratory, Richland, WA (United States); Anderson, Kim A., E-mail: kim.anderson@oregonstate.edu [Department of Environmental and Molecular Toxicology, the Environmental Health Sciences Center, Oregon State University, Corvallis, OR (United States); Waters, Katrina M., E-mail: katrina.waters@pnl.gov [Computational Biology and Bioinformatics, Pacific Northwest National Laboratory, Richland, WA (United States); Tanguay, Robert L., E-mail: robert.tanguay@oregonstate.edu [Department of Environmental and Molecular Toxicology, the Environmental Health Sciences Center, Oregon State University, Corvallis, OR (United States)

    2013-09-01

    Oxygenated polycyclic aromatic hydrocarbons (OPAHs) are byproducts of combustion and photo-oxidation of parent PAHs. OPAHs are widely present in the environment and pose an unknown hazard to human health. The developing zebrafish was used to evaluate a structurally diverse set of 38 OPAHs for malformation induction, gene expression changes and mitochondrial function. Zebrafish embryos were exposed from 6 to 120 h post fertilization (hpf) to a dilution series of 38 different OPAHs and evaluated for 22 developmental endpoints. AHR activation was determined via CYP1A immunohistochemistry. Phenanthrenequinone (9,10-PHEQ), 1,9-benz-10-anthrone (BEZO), xanthone (XAN), benz(a)anthracene-7,12-dione (7,12-B[a]AQ), and 9,10-anthraquinone (9,10-ANTQ) were evaluated for transcriptional responses at 48 hpf, prior to the onset of malformations. qRT-PCR was conducted for a number of oxidative stress genes, including the glutathione transferase(gst), glutathione peroxidase(gpx), and superoxide dismutase(sod) families. Bioenergetics was assayed to measure in vivo oxidative stress and mitochondrial function in 26 hpf embryos exposed to OPAHs. Hierarchical clustering of the structure-activity outcomes indicated that the most toxic of the OPAHs contained adjacent diones on 6-carbon moieties or terminal, para-diones on multi-ring structures. 5-carbon moieties with adjacent diones were among the least toxic OPAHs while the toxicity of multi-ring structures with more centralized para-diones varied considerably. 9,10-PHEQ, BEZO, 7,12-B[a]AQ, and XAN exposures increased expression of several oxidative stress related genes and decreased oxygen consumption rate (OCR), a measurement of mitochondrial respiration. Comprehensive in vivo characterization of 38 structurally diverse OPAHs indicated differential AHR dependency and a prominent role for oxidative stress in the toxicity mechanisms. - Highlights: • OPAHs are byproducts of combustion present in the environment. • OPAHs pose a largely

  18. Toxicity assessment in marine sediment for the Terra Nova environmental effects monitoring program (1997-2010)

    Science.gov (United States)

    Whiteway, Sandra A.; Paine, Michael D.; Wells, Trudy A.; DeBlois, Elisabeth M.; Kilgour, Bruce W.; Tracy, Ellen; Crowley, Roger D.; Williams, Urban P.; Janes, G. Gregory

    2014-12-01

    This paper discusses toxicity test results on sediments from the Terra Nova offshore oil development. The Terra Nova Field is located on the Grand Banks approximately 350 km southeast of Newfoundland (Canada). The amphipod (Rhepoxynius abronius) survival and solid phase luminescent bacteria (Vibrio fischeri, or Microtox) assays were conducted on sediment samples collected from approximately 50 stations per program year around Terra Nova during baseline (1997), prior to drilling, and in 2000, 2001, 2002, 2004, 2006, 2008 and 2010 after drilling began. The frequency of toxic responses in the amphipod toxicity test was low. Of the ten stations that were toxic in environmental effects monitoring (EEM) years, only one (station 30(FE)) was toxic in more than one year and could be directly attributed to Terra Nova project activities. In contrast, 65 (18%) of 364 EEM samples were toxic to Microtox. Microtox toxicity in EEM years was not related to distance from Terra Nova drill centres or concentrations of >C10-C21 hydrocarbons or barium, the primary constituents of the synthetic-based drill muds used at Terra Nova. Of the variables tested, fines and strontium levels showed the strongest (positive) correlations with toxicity. Neither fines nor strontium levels were affected by drill cuttings discharge at Terra Nova, except at station 30(FE) (and that station was not toxic to Microtox). Benthic macro-invertebrate abundance, richness and diversity were greater in toxic than in non-toxic sediments. Therefore, Microtox responses indicating toxicity were associated with positive biological responses in the field. This result may have been an indirect function of the increased abundance of most invertebrate taxa in less sandy sediments with higher gravel content, where fines and strontium levels and, consequently, toxicity to Microtox were high; or chemical substances released by biodegradation of organic matter, where invertebrates are abundant, may be toxic to Microtox. Given

  19. Glyphosate and its formulations – Toxicity, occupational and environmental exposure

    Directory of Open Access Journals (Sweden)

    Marta Kwiatkowska

    2013-10-01

    Full Text Available Glyphosate (N-(phosphonomethylglycine is an active ingredient of the most widely used herbicide formulations in protecting agricultural and horticultural crops. Numerous results (mostly published in the years 2010-2013 concerning the action of glyphosate and its formulations in the recent decade were analyzed. Initial reports about alleged biodegradability of glyphosate in the environment turned out to be wrong. It has been shown that glyphosate remains in the soil and can reach people by spreading along with groundwater. Recent publications have shown that glyphosate is detected at low concentrations in the human blood. Publications cited in this article, which indicate a possible induction of neoplastic changes by glyphosate formulation, have raised great concern and controversy in the scientific world. Presenting adverse effects of glyphosate and its formulations we focused on the role of glyphosate formulations in hormonal disorders by impeding the expression of steroidogenic acute regulatory protein and the inhibition of aromatase activity. The impact of glyphosate on oxygen reactive species formation, changes in redox system and the effect on necrosis and apoptosis in various types of cells was shown. We also revealed that glyphosate as a phosphonate herbicide does not inhibit directly the activity of acetylcholinesterase. Based on numerous studies it was noted that commercial formulations of glyphosate exhibit higher toxicity than that of the active substance itself. The discussed problems clearly show the need to evaluate the toxicity of glyphosate and its formulations and related potential threat to humans. Med Pr 2013;64(5:717–729

  20. Toxic Tourism: A New Itinerary for the Environmental Justice Movement.

    Science.gov (United States)

    Di Chiro, Giovanna

    2001-01-01

    Tours of minority group neighborhoods show participants the effects of polluting industries that are disproportionately sited near them. The tours make people aware of this overt environmental racism and inspire them to take action. Such tours must be handled with tact, preferably by the affected communities themselves, to avoid voyeurism and…

  1. Modulation of persistent organic pollutant toxicity through nutritional intervention: emerging opportunities in biomedicine and environmental remediation

    Science.gov (United States)

    Petriello, Michael C.; Newsome, Bradley J.; Dziubla, Thomas D.; Hilt, J. Zach; Bhattacharyya, Dibakar; Hennig, Bernhard

    2014-01-01

    Environmental pollution is increasing worldwide, and there is evidence that exposure to halogenated persistent organic pollutants (POPs) such as polychlorinated biphenyls can contribute to the pathology of inflammatory diseases such as atherosclerosis, diabetes, and cancer. Pollutant removal from contaminated sites and subsequent pollutant degradation are critical for reducing the long-term health risks associated with exposure. However, complete remediation of a toxicant from the environment is very difficult and cost-prohibitive. Furthermore, remediation technologies often result in the generation of secondary toxicants. Considering these circumstances, environmentally-friendly and sustainable remediation technologies and biomedical solutions to reduce vulnerability to environmental chemical insults need to be explored to reduce the overall health risks associate with exposure to environmental pollutants. We propose that positive lifestyle changes such as healthful nutrition and consumption of diets rich in fruits and vegetables or bioactive nutrients with antioxidant and/or anti-inflammatory properties will reduce the body’s vulnerability to environmental stressors and thus reduce toxicant-mediated disease pathologies. Interestingly, emerging evidence now implicates the incorporation of bioactive nutrients, such as plant-derived polyphenols, in technologies focused on the capture, sensing and remediation of halogenated POPs. We propose that human nutritional intervention in concert with the use of natural polyphenol sensing and remediation platforms may provide a sensible means to develop primary and long-term prevention strategies of diseases associated with many environmental toxic insults including halogenated POPs. PMID:24530186

  2. Toxicity of the synthetic polymeric 3-alkylpyridinium salt (APS3) is due to specific block of nicotinic acetylcholine receptors.

    Science.gov (United States)

    Grandič, Marjana; Aráoz, Romulo; Molgó, Jordi; Turk, Tom; Sepčić, Kristina; Benoit, Evelyne; Frangež, Robert

    2013-01-01

    The in vivo and in vitro toxic effects of the synthetic polymeric 3-alkylpyridinium salt (APS3), from the Mediterranean marine sponge Reniera sarai, were evaluated on mammals, with emphasis to determine its mode of action. The median lethal doses of APS3 were 7.25 and higher that 20mg/kg in mouse and rat, respectively. Intravenous administration of 7.25 and 20mg/kg APS3 to rat caused a significant fall followed by an increase in mean arterial blood pressure accompanied by tachycardia. In addition, cumulative doses of APS3 (up to 60 mg/kg) inhibited rat nerve-evoked skeletal muscle contraction in vivo, with a median inhibitory dose (ID(50)) of 37.25mg/kg. When administrated locally by intramuscular injection to mouse, APS3 decreased the compound muscle action potential recorded in response to in vivo nerve stimulation, with an ID(50) of 0.5mg/kg. In vitro experiments confirmed the inhibitory effect of APS3 on mouse hemidiaphragm nerve-evoked muscle contraction with a median inhibitory concentration (IC(50)) of 20.3 μM, without affecting directly elicited muscle contraction. The compound inhibited also miniature endplate potentials and nerve-evoked endplate potentials with an IC(50) of 7.28 μM in mouse hemidiaphragm. Finally, APS3 efficiently blocked acetylcholine-activated membrane inward currents flowing through Torpedo nicotinic acetylcholine receptors (nAChRs) incorporated to Xenopus oocytes, with an IC(50) of 0.19 μM. In conclusion, our results strongly suggest that APS3 blocks muscle-type nAChRs, and show for the first time that in vivo toxicity of APS3 is likely to occur through an antagonist action of the compound on these receptors.

  3. Plants as Useful Vectors to Reduce Environmental Toxic Arsenic Content

    Directory of Open Access Journals (Sweden)

    Nosheen Mirza

    2014-01-01

    Full Text Available Arsenic (As toxicity in soil and water is an increasing menace around the globe. Its concentration both in soil and environment is due to natural and anthropogenic activities. Rising arsenic concentrations in groundwater is alarming due to the health risks to plants, animals, and human beings. Anthropogenic As contamination of soil may result from mining, milling, and smelting of copper, lead, zinc sulfide ores, hide tanning waste, dyes, chemical weapons, electroplating, gas exhaust, application of municipal sludge on land, combustion of fossil fuels, As additives to livestock feed, coal fly ash, and use of arsenical pesticides in agricultural sector. Phytoremediation can be viewed as biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system that enhances the natural ecosystems for subsequent productive use. The present review presents recent scientific developments regarding phytoremediation of arsenic contaminated environments and its possible detoxification mechanisms in plants.

  4. Overview and management of toxicities of immune checkpoint-blocking drugs

    Directory of Open Access Journals (Sweden)

    Economopoulou Panagiota

    2016-03-01

    Full Text Available Immunotherapy is considered to be the most important breakthrough in cancer management in the past few years. This success was based on the scientific understanding of immune mechanisms due to improvement in preclinical science and the introduction of new methods of investigation. Immune checkpoint inhibitors (ICIs are among the most promising drugs in the field of immune-oncology; they represent monoclonal antibodies that modulate the effects of immune checkpoints, such as cytotoxic T lymphocyte Antigen 4 (CTLA-4 and Programmed Cell Death protein 1 (PD-1, which are co-inhibitory signals responsible for immune suppression. Despite clinical benefits, ICIs are immune activating agents that are associated with a number of important side effects (immune-related adverse events-irAEs, attributed to organ-specific inflammation. Herein, we review the toxicities of ICIs, highlighting the importance of early identification and management.

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

    DEFF Research Database (Denmark)

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

    1998-01-01

    . The assessment proceeds through the steps of classification, characterization, normalization and valuation. In the classification step attention is focused on intrinsic toxicity, low biodegradability and potential for bioconcentration as properties that predicpose a substance for ecotoxicity. No concrete values...... references derived for each of these scenarios are presented as personal equivalents for citizens in the considered region. Valuation Applying the "distance to target principle to the present Danish political reduction targets for toxicity a weighting factor is derived to be used in the quantitative weighing...... of the potential contribution to toxicity against the potential contributions to other environmental effect types....

  6. Toxicity of five antibiotics and their mixtures towards photosynthetic aquatic organisms: implications for environmental risk assessment.

    Science.gov (United States)

    González-Pleiter, Miguel; Gonzalo, Soledad; Rodea-Palomares, Ismael; Leganés, Francisco; Rosal, Roberto; Boltes, Karina; Marco, Eduardo; Fernández-Piñas, Francisca

    2013-04-15

    The individual and combined toxicities of amoxicillin, erythromycin, levofloxacin, norfloxacin and tetracycline have been examined in two organisms representative of the aquatic environment, the cyanobacterium Anabaena CPB4337 as a target organism and the green alga Pseudokirchneriella subcapitata as a non-target organism. The cyanobacterium was more sensitive than the green alga to the toxic effect of antibiotics. Erythromycin was highly toxic for both organisms; tetracycline was more toxic to the green algae whereas the quinolones levofloxacin and norfloxacin were more toxic to the cyanobacterium than to the green alga. Amoxicillin also displayed toxicity to the cyanobacterium but showed no toxicity to the green alga. The toxicological interactions of antibiotics in the whole range of effect levels either in binary or multicomponent mixtures were analyzed using the Combination Index (CI) method. In most cases, synergism clearly predominated both for the green alga and the cyanobacterium. The CI method was compared with the classical models of additivity Concentration Addition (CA) and Independent Action (IA) finding that CI could accurately predict deviations from additivity. Risk assessment was performed by calculating the ratio between Measured Environmental Concentration (MEC) and the Predicted No Effect Concentration (PNEC). A MEC/PNEC ratio higher than 1 was found for the binary erythromycin and tetracycline mixture in wastewater effluents, a combination which showed a strong synergism at low effect levels in both organisms. From the tested antibiotic mixtures, it can be concluded that certain specific combinations may pose a potential ecological risk for aquatic ecosystems with the present environmentally measured concentrations.

  7. O-GlcNAc modification blocks the aggregation and toxicity of the protein α-synuclein associated with Parkinson's disease

    Science.gov (United States)

    Marotta, Nicholas P.; Lin, Yu Hsuan; Lewis, Yuka E.; Ambroso, Mark R.; Zaro, Balyn W.; Roth, Maxwell T.; Arnold, Don B.; Langen, Ralf; Pratt, Matthew R.

    2015-11-01

    Several aggregation-prone proteins associated with neurodegenerative diseases can be modified by O-linked N-acetyl-glucosamine (O-GlcNAc) in vivo. One of these proteins, α-synuclein, is a toxic aggregating protein associated with synucleinopathies, including Parkinson's disease. However, the effect of O-GlcNAcylation on α-synuclein is not clear. Here, we use synthetic protein chemistry to generate both unmodified α-synuclein and α-synuclein bearing a site-specific O-GlcNAc modification at the physiologically relevant threonine residue 72. We show that this single modification has a notable and substoichiometric inhibitory effect on α-synuclein aggregation, while not affecting the membrane binding or bending properties of α-synuclein. O-GlcNAcylation is also shown to affect the phosphorylation of α-synuclein in vitro and block the toxicity of α-synuclein that was exogenously added to cells in culture. These results suggest that increasing O-GlcNAcylation may slow the progression of synucleinopathies and further support a general function for O-GlcNAc in preventing protein aggregation.

  8. Environmental Quality Research - Fate of Toxic Jet Fuel Components in Aquatic Systems

    Science.gov (United States)

    1982-10-01

    Analysis (Hydrocarbon) Toxicity Fuels, Jet Artemia salina uels r olbl trct ABSTRACT (Continue on reverse oIde If necessary and identify by block number...effect of the fuel water solib•,% extzract (WSF) on the hatchability of Artemia salina eggs. JF-4 sarnriles frorr, iilcrent sources were shown to...Bioassay Control Sample 14 3 Effect of Storage on JP-4 WSF Hydrocarbons 15 4 Effect of Seawator Salinity on Hatch Efficiency of Artemia salina Eggs 17 5

  9. Developmental toxicity of UV filters and environmental exposure: a review.

    Science.gov (United States)

    Schlumpf, Margret; Durrer, Stefan; Faass, Oliver; Ehnes, Colin; Fuetsch, Michaela; Gaille, Catherine; Henseler, Manuel; Hofkamp, Luke; Maerkel, Kirsten; Reolon, Sasha; Timms, Barry; Tresguerres, Jesus A F; Lichtensteiger, Walter

    2008-04-01

    Several ultraviolet (UV) filters exhibit estrogenic, some also anti-androgenic activity. They are present in waste water treatment plants, surface waters and biosphere including human milk, suggesting potential exposure during development. Developmental toxicity was studied in rats for the UV filters 4-methylbenzylidene camphor (4-MBC, 0.7, 7, 24, 47 mg/kg/day) and 3-benzylidene camphor (3-BC, 0.07, 0.24, 0.7, 2.4, 7 mg/kg/day) administered in chow to the parent generation before mating, during pregnancy and lactation, and to the offspring until adulthood. Neonates exhibited enhanced prostate growth after 4-MBC and altered uterine gene expression after both chemicals. 4-MBC and 3-BC delayed male puberty and affected reproductive organ weights of adult offspring. Effects on the thyroid axis were also noted. Expression and oestrogen sensitivity of oestrogen-regulated genes and nuclear receptor coregulator levels were altered at mRNA and protein levels in adult uterus, prostate and brain regions involved in gonadal control and sexual behaviour. Female sexual behaviour was impaired by both filters; 3-benzylidene camphor caused irregular cycles. Classical endpoints exhibited lowest observed adverse effect levels (LOAELs) and no observed adverse effect levels (NOAELs) of 7/0.7 mg/kg for 4-MBC and 0.24/0.07 mg/kg for 3-BC. Molecular endpoints were affected by the lowest doses studied. Our data indicate that the potential risk posed by endocrine active UV filters warrants further investigations.

  10. Environmental impact by toxic compounds from waste treatment; Miljoepaaverkan fraan toxiska aemnen vid hantering av avfall

    Energy Technology Data Exchange (ETDEWEB)

    Loefblad, Gun; Bisaillon, Mattias; Sundberg, Johan (Profu AB (Sweden))

    2010-07-01

    The study deals with emissions of toxic compounds from waste treatment to the environment with the aim of improving the state of knowledge and to find a way of describing the environmental impact from these substances. Toxicity is one of a number of environmental aspects necessary to address in the planning of waste treatment and in the daily waste treatment routines in order to fulfill the environmental objective A Non-Toxic Environment and other environmental requirements. The study includes waste to incineration, composting and anaerobic digestion. A comparison between methods were made for biological household waste. According to our study, the compounds of importance for waste treatment are metals and persistent organic compounds. These tend to bioaccumulate and enrich in food chains. The substances are important for the environmental objective A Non-Toxic Environment. In a first step the compounds chosen in this study may be suggested for describing toxicity from waste treatment: As, Cd, Cu, Hg, Pb, dioxin, PCB, the phthalate DEHP and the brominated flame retardant HBCDD. Other substances may be added to the list in a next step from up-dated and quality-assured characterisation factors or from other requirements or preferences. There is a limited knowledge on toxic compounds in waste flows and in different environmental compartments. More data are available for metals than for organic substances. There is also a limited knowledge on the fate of the compounds during the waste treatment processes. Most information is found for incineration. During composting and anaerobic digestion the metals will mainly be emitted to the environment by use of the compost and the anaerobic digestion residue. Organic substances will to some extent be degraded during the processes. However, there are gaps of knowledge to fill for the further work on estimating toxic emissions. There is mainly a need for more extensive data on toxic compounds in waste and their variations. A test

  11. U.S. EPA requires Cupertino cement company to report toxic chemicals, commit to environmental projects

    Science.gov (United States)

    SAN FRANCISCO - The U.S. Environmental Protection Agency announced a settlement with Lehigh Southwest Cement Company for failing to properly report releases of toxic chemicals at its Cupertino, Calif. plant. The company is required to pay a $47,600

  12. Acute Toxicity and Environmental Risks of Five Veterinary Pharmaceuticals for Aquatic Macroinvertebrates.

    Science.gov (United States)

    Bundschuh, Mirco; Hahn, Torsten; Ehrlich, Bert; Höltge, Sibylla; Kreuzig, Robert; Schulz, Ralf

    2016-02-01

    Due to the high use of antibiotics and antiparasitics for the treatment of livestock, there is concern about the potential impacts of the release of these compounds into freshwater ecosystems. In this context, the present study quantified the acute toxicity of two antibiotics (sulfadiazine and sulfadimidine), and three antiparasitic agents (flubendazole, fenbendazole, ivermectin) for nine freshwater invertebrate species. These experiments revealed a low degree of toxicity for the sulfonamide antibiotics, with limited implications in the survival of all test species at the highest test concentrations (50 and 100 mg/L). In contrast, all three antiparasitic agents indicated on the basis of their acute toxicity risks for the aquatic environment. Moreover, chronic toxicity data from the literature for antiparasitics, including effects on reproduction in daphnids, support the concern about the integrity of aquatic ecosystems posed by releases of these compounds. Thus, these pharmaceuticals warrant further careful consideration by environmental risk managers.

  13. U.S./Mexico Border environmental study toxics release inventory data, 1988--1992

    Energy Technology Data Exchange (ETDEWEB)

    O`Brien, R.F.; LoPresti, C.A.

    1996-02-01

    This is a report on industrial toxic chemical releases and transfers based on information reported to the Toxics Release Inventory (TRI), a database maintained by the USEPA. This document discusses patterns of toxic chemical releases to the atmosphere, to water, to the land, and to underground injection; and transfers of toxic chemicals to Publicly Owned Treatment Works (POTW), and for disposal, treatment and other off-site transfers during the TRI reporting years 1988--1992. Geographic coverage is limited to the US side of the ``Border Area``, the geographic area situated within 100 km of the US/Mexico international boundary. A primary purpose of this study is to provide background information that can be used in the future development of potential ``indicator variables`` for tracking environmental and public health status in the Border Area in conjunction with the implementation of the North American Free Trade Agreement (NAFTA).

  14. Perceptions of environmental health risks among residents in the “Toxic Doughnut”: Opportunities for risk screening and community mobilization

    Science.gov (United States)

    Surrounded by landfills, and toxic and hazardous facilities, Altgeld Gardens is located in a “toxic doughnut.” With high rates of environmentally-related conditions, residents have called for a community-based environmental health assessment to improve overall health in their com...

  15. Interannual variability in the timing of New England shellfish toxicity and relationships to environmental forcing.

    Science.gov (United States)

    Nair, Apurva; Thomas, Andrew C; Borsuk, Mark E

    2013-03-01

    Routine monitoring along the coast of the Gulf of Maine (GoM) reveals shellfish toxicity nearly every summer, but at varying times, locations, and magnitudes. The responsible toxin is known to be produced by the dinoflagellate Alexandrium fundyense, yet there is little apparent association between Alexandrium abundance and shellfish toxicity. One possibility is that toxic cells are persistent in offshore areas and variability in shellfish toxicity is caused not by changes in overall abundance, but rather by variability in transport processes. Measurements of offshore Alexandrium biomass are scarce, so we bypass cell abundance as an explanatory variable and focus instead on the relations between shellfish toxicity and concurrent metrics of GoM meteorology, hydrology, and oceanography. While this yields over two decades (1985-2005) of data representing a variety of interannual conditions, the toxicity data are gappy in spatial and temporal coverage. We address this through a combination of parametric curve fitting and hierarchical cluster analysis to reveal eight archetypical modes of seasonal toxicity timing. Groups of locations are then formed that have similar interannual patterns in these archetypes. Finally, the interannual patterns within each group are related to available environmental metrics using classification trees. Results indicate that a weak cross-shore sea surface temperature (SST) gradient in the summer is the strongest correlate of shellfish toxicity, likely by signifying a hydrological connection between offshore Alexandrium populations and near-shore shellfish beds. High cumulative downwelling wind strength early in the season is revealed as a precursor consistent with this mechanism. Although previous studies suggest that alongshore transport is important in moving Alexandrium from the eastern to western GoM, alongshore SST gradient is not an important correlate of toxicity in our study. We conclude by discussing the implications of our results

  16. Early Life Origins of Metabolic Syndrome: The Role of Environmental Toxicants.

    Science.gov (United States)

    Wang, Guoying; Chen, Zhu; Bartell, Tami; Wang, Xiaobin

    2014-03-01

    Metabolic syndrome (MetS) affects more than 47 million people in the U.S. Even more alarming, MetS, once regarded as an "adult problem", has become increasingly common in children. To date, most related research and intervention efforts have occurred in the adult medicine arena, with limited understanding of the root causes and lengthy latency of MetS. This review highlights new science on the early life origins of MetS, with a particular focus on exposure to two groups of environmental toxicants: endocrine disrupting chemicals (EDCs) and metals during the prenatal and early postnatal periods, and their specific effects and important differences in the development of MetS. It also summarizes available data on epigenetic effects, including the role of EDCs in the androgen/estrogen pathways. Emerging evidence supports the link between exposures to environmental toxicants during early life and the development of MetS later in life. Additional research is needed to address important research gaps in this area, including prospective birth cohort studies to delineate temporal and dose-response relationships, important differences in the effects of various environmental toxicants and their joint effects on MetS, as well as epigenetic mechanisms underlying the effects of specific toxicants such as EDCs and metals.

  17. The U.S. Environmental Protection Agency strategic plan for evaluating the toxicity of chemicals.

    Science.gov (United States)

    Firestone, Michael; Kavlock, Robert; Zenick, Hal; Kramer, Melissa

    2010-02-01

    In the 2007 report Toxicity Testing in the 21st Century: A Vision and a Strategy, the U.S. National Academy of Sciences envisioned a major transition in toxicity testing from cumbersome, expensive, and lengthy in vivo testing with qualitative endpoints, to in vitro robotic high-throughput screening with mechanistic quantitative parameters. Recognizing the need for agencies to partner and collaborate to ensure global harmonization, standardization, quality control and information sharing, the U.S. Environmental Protection Agency is leading by example and has established an intra-agency Future of Toxicity Testing Workgroup (FTTW). This workgroup has produced an ambitious blueprint for incorporating this new scientific paradigm to change the way chemicals are screened and evaluated for toxicity. Four main components of this strategy are discussed, as follows: (1) the impact and benefits of various types of regulatory activities, (2) chemical screening and prioritization, (3) toxicity pathway-based risk assessment, and (4) institutional transition. The new paradigm is predicated on the discovery of molecular perturbation pathways at the in vitro level that predict adverse health effects from xenobiotics exposure, and then extrapolating those events to the tissue, organ, or whole organisms by computational models. Research on these pathways will be integrated and compiled using the latest technology with the cooperation of global agencies, industry, and other stakeholders. The net result will be that chemical toxicity screening will become more efficient and cost-effective, include real-world exposure assessments, and eliminate currently used uncertainty factors.

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

    Directory of Open Access Journals (Sweden)

    Sebastián Sauco

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

  19. Inorganic nanomaterials in the aquatic environment: behavior, toxicity, and interaction with environmental elements

    Directory of Open Access Journals (Sweden)

    Krzyżewska Iwona

    2016-03-01

    Full Text Available The aim of this paper is to present characteristics, toxicity and environmental behavior of nanoparticles (NPs (silver, copper, gold, zinc oxide, titanium dioxide, iron oxide that most frequently occur in consumer products. In addition, NPs are addressed as the new aquatic environmental pollutant of the 21st century. NPs are adsorbed onto particles in the aquatic systems (clay minerals, fulvic and humic acids, or they can adsorb environmental pollutants (heavy metal ions, organic compounds. Nanosilver (nAg is released from consumer products into the aquatic environment. It can threaten aquatic organisms with high toxicity. Interestingly, copper nanoparticles (Cu-NPs demonstrate higher toxicity to bacteria and aquatic microorganisms than those of nanosilver nAg. Their small size and reactivity can cause penetration into the tissues and interfere with the metabolic systems of living organisms and bacterial biogeochemical cycles. The behavior of NPs is not fully recognized. Nevertheless, it is known that NPs can agglomerate, bind with ions (chlorides, sulphates, phosphates or organic compounds. They can also be bound or immobilized by slurry. The NPs behavior depends on process conditions, i.e. pH, ionic strength, temperature and presence of other chemical compounds. It is unknown how NPs behave in the aquatic environment. Therefore, the research on this problem should be carried out under different process conditions. As for the toxicity, it is important to understand where the differences in the research results come from. As NPs have an impact on not only aquatic organisms but also human health and life, it is necessary to recognize their toxic doses and know standards/regulations that determine the permissible concentrations of NPs in the environment.

  20. Organotins: a review of their reproductive toxicity, biochemistry, and environmental fate.

    Science.gov (United States)

    Graceli, Jones Bernardes; Sena, Gabriela Cavati; Lopes, Pedro Francisco Iguatemy; Zamprogno, Gabriela Carvalho; da Costa, Mércia Barcellos; Godoi, Ana Flavia Locateli; Dos Santos, Dayana Moscardi; de Marchi, Mary Rosa Rodrigues; Dos Santos Fernandez, Marcos Antonio

    2013-04-01

    The review purposes are to (1) evaluate the experimental evidence for adverse effects on reproduction and metabolism and (2) identify the current knowledge of analytical procedures, biochemistry and environmental aspects relating to organotins. Organotins are pollutants that are used as biocides in antifouling paints. They produce endocrine-disrupting effects in mollusks, such as imposex. In rodents, organotin exposure induces developmental and reproductive toxicity as well as alteration of metabolic homeostasis through its action as an obesogen. The adverse effects that appear in rodents have raised concerns about organotins' potential health risk to humans in relation to organotin exposure. At present, triorganotin, such as tributyltin, have been demonstrated to produce imposex, and mammalian reproductive and metabolic toxicity. For most mammals, triorganotin exposure predominantly occurs through the ingestion, and this compound can cross the placenta. With these risks in mind, it is important to improve our knowledge of organotins' effects on environmental health.

  1. Effects of nanoplastics and microplastics on toxicity, bioaccumulation, and environmental fate of phenanthrene in fresh water.

    Science.gov (United States)

    Ma, Yini; Huang, Anna; Cao, Siqi; Sun, Feifei; Wang, Lianhong; Guo, Hongyan; Ji, Rong

    2016-12-01

    Contamination of fine plastic particles (FPs), including micrometer to millimeter plastics (MPs) and nanometer plastics (NPs), in the environment has caught great concerns. FPs are strong adsorbents for hydrophobic toxic pollutants and may affect their fate and toxicity in the environment; however, such information is still rare. We studied joint toxicity of FPs with phenanthrene to Daphnia magna and effects of FPs on the environmental fate and bioaccumulation of (14)C-phenanthrene in fresh water. Within the five sizes particles we tested (from 50 nm to 10 μm), 50-nm NPs showed significant toxicity and physical damage to D. magna. The joint toxicity of 50-nm NPs and phenanthrene to D. magna showed an additive effect. During a 14-days incubation, the presence of NPs significantly enhanced bioaccumulation of phenanthrene-derived residues in daphnid body and inhibited the dissipation and transformation of phenanthrene in the medium, while 10-μm MPs did not show significant effects on the bioaccumulation, dissipation, and transformation of phenanthrene. The differences may be attributed to higher adsorption of phenanthrene on 50-nm NPs than 10-μm MPs. Our findings underlined the high potential ecological risks of FPs, and suggested that NPs should be given more concerns, in terms of their interaction with hydrophobic pollutants in the environment.

  2. Glyphosate: environmental contamination, toxicity and potential risks to human health via food contamination.

    Science.gov (United States)

    Bai, Shahla Hosseini; Ogbourne, Steven M

    2016-10-01

    Glyphosate has been the most widely used herbicide during the past three decades. The US Environmental Protection Agency (EPA) classifies glyphosate as 'practically non-toxic and not an irritant' under the acute toxicity classification system. This classification is based primarily on toxicity data and due to its unique mode of action via a biochemical pathway that only exists in a small number of organisms that utilise the shikimic acid pathway to produce amino acids, most of which are green plants. This classification is supported by the majority of scientific literature on the toxic effects of glyphosate. However, in 2005, the Food and Agriculture Organisation (FAO) reported that glyphosate and its major metabolite, aminomethylphosphonic acid (AMPA), are of potential toxicological concern, mainly as a result of accumulation of residues in the food chain. The FAO further states that the dietary risk of glyphosate and AMPA is unlikely if the maximum daily intake of 1 mg kg(-1) body weight (bw) is not exceeded. Research has now established that glyphosate can persist in the environment, and therefore, assessments of the health risks associated with glyphosate are more complicated than suggested by acute toxicity data that relate primarily to accidental high-rate exposure. We have used recent literature to assess the possible risks associated with the presence of glyphosate residues in food and the environment.

  3. Microencapsulated Aliivibrio fischeri in Alginate Microspheres for Monitoring Heavy Metal Toxicity in Environmental Waters

    Directory of Open Access Journals (Sweden)

    Dedi Futra

    2014-12-01

    Full Text Available In this article a luminescence fiber optic biosensor for the microdetection of heavy metal toxicity in waters based on the marine bacterium Aliivibrio fischeri (A. fischeri encapsulated in alginate microspheres is described. Cu(II, Cd(II, Pb(II, Zn(II, Cr(VI, Co(II, Ni(II, Ag(I and Fe(II were selected as sample toxic heavy metal ions for evaluation of the performance of this toxicity microbiosensor. The loss of bioluminescence response from immobilized A. fischeri bacterial cells corresponds to changes in the toxicity levels. The inhibition of the luminescent biosensor response collected at excitation and emission wavelengths of 287 ± 2 nm and 487 ± 2 nm, respectively, was found to be reproducible and repeatable within the relative standard deviation (RSD range of 2.4–5.7% (n = 8. The toxicity biosensor based on alginate micropsheres exhibited a lower limit of detection (LOD for Cu(II (6.40 μg/L, Cd(II (1.56 μg/L, Pb(II (47 μg/L, Ag(I (18 μg/L than Zn(II (320 μg/L, Cr(VI (1,000 μg/L, Co(II (1700 μg/L, Ni(II (2800 μg/L, and Fe(III (3100 μg/L. Such LOD values are lower when compared with other previous reported whole cell toxicity biosensors using agar gel, agarose gel and cellulose membrane biomatrices used for the immobilization of bacterial cells. The A. fischeri bacteria microencapsulated in alginate biopolymer could maintain their metabolic activity for a prolonged period of up to six weeks without any noticeable changes in the bioluminescence response. The bioluminescent biosensor could also be used for the determination of antagonistic toxicity levels for toxicant mixtures. A comparison of the results obtained by atomic absorption spectroscopy (AAS and using the proposed luminescent A. fischeri-based biosensor suggests that the optical toxicity biosensor can be used for quantitative microdetermination of heavy metal toxicity in environmental water samples.

  4. Intrinsic Optical Activity and Environmental Perturbations: Solvation Effects in Chiral Building Blocks

    Science.gov (United States)

    Lemler, Paul M.; Vaccaro, Patrick

    2016-06-01

    The non-resonant interaction of electromagnetic radiation with an isotropic ensemble of chiral molecules, which causes the incident state of linear polarization to undergo a signed rotation, long has served as a metric for gauging the enantiomeric purity of asymmetric syntheses. While the underlying phenomenon of circular birefringence (CB) typically is probed in the condensed phase, recent advances in ultrasensitive circular-differential detection schemes, as exemplified by the techniques of Cavity Ring-Down Polarimetry (CRDP), have permitted the first quantitative analyses of such processes to be performed in rarefied media. Efforts to extend vapor-phase investigations of CB to new families of chiral substrates will be discussed, with particular emphasis directed towards the elucidation of intrinsic (e.g., solvent-free) properties and their mediation by environmental perturbations (e.g., solvation). Specific species targeted by this work will include the stereoselective building blocks phenylpropylene oxide and α-methylbenzyl amine, both of which exhibit pronounced solvent-dependent changes in measured optical activity. The nature of chiroptical response in different environments will be highlighted, with quantum-chemical calculations serving to unravel the structural and electronic provenance of observed behavior.

  5. Effect of Some Environmental Factors on the Toxicity of Azadirachtin to the Egyptian Cotton Leafworm Spodoptera littoralis (Boisduval (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    El-Sayed H. Shaurub

    2014-12-01

    Full Text Available Although the bio-degradation of azadirachtin was well studied under storage or environmental conditions, its toxicity was not characterized so far under the impact of environmental conditions. Therefore, the present study aims to elucidate the toxicity of azadirachtin, at the level of LC50, to the fourth larval instars of Spodoptera littoralis (Boisduval under the stress of temperature, ultraviolet radiation (365 nm (UV-A and of artificial sunlight. The increase in post-treatment temperatures insignificantly affected azadirachtin toxicity. Likewise, insignificant change was also attained for the increase in the exposure periods of both UV and sunlight, except for exposure to sunlight without UV filter starting from 10 h, where the toxicity of azadirachtin was significantly declined. It can be concluded that azadirachtin toxicity will last efficiently against S. littoralis larvae under the stress of the environmental factors prevailing during the season of cotton cultivation in Egypt.

  6. Allium-test as a tool for toxicity testing of environmental radioactive-chemical mixtures

    Science.gov (United States)

    Oudalova, A. A.; Geras’kin, S. A.; Dikareva, N. S.; Pyatkova, S. V.

    2017-01-01

    Bioassay-based approaches have been propagated to assess toxicity of unknown mixtures of environmental contaminants, but it was rarely applied in cases of chemicals with radionuclides combinations. Two Allium-test studies were performed to assess environmental impact from potential sources of combined radioactive-chemical pollution. Study sites were located at nuclear waste storage facilities in European and in Far-Eastern parts of Russia. As environmental media under impact, waters from monitor wells and nearby water bodies were tested. Concentrations of some chemicals and radionuclides in the samples collected enhanced the permitted limits. Cytogenetic and cytotoxic effects were used as biological endpoints, namely, frequency and spectrum of chromosome aberrations and mitotic abnormalities in anatelophase cells as well as mitotic activity in Allium root tips. Sample points were revealed where waters have an enhanced mutagenic potential. The findings obtained could be used to optimize monitoring system and advance decision making on management and rehabilitation of industrial sites. The Allium-test could be recommended and applied as an effective tool for toxicity testing in case of combined contamination of environmental compartments with radionuclides and chemical compounds.

  7. Depth Profiling (ICP-MS Study of Toxic Metal Buildup in Concrete Matrices: Potential Environmental Impact

    Directory of Open Access Journals (Sweden)

    Ghada Bassioni

    2010-10-01

    Full Text Available This paper explores the potential of concrete material to accumulate toxic trace elements using ablative laser technology (ICP-MS. Concrete existing in offshore structures submerged in seawater acts as a sink for hazardous metals, which could be gradually released into the ocean creating pollution and anoxic conditions for marine life. Ablative laser technology is a valuable tool for depth profiling concrete to evaluate the distribution of toxic metals and locate internal areas where such metals accumulate. Upon rapid degradation of concrete these “hotspots” could be suddenly released, thus posing a distinct threat to aquatic life. Our work simulated offshore drilling conditions by immersing concrete blocks in seawater and investigating accumulated toxic trace metals (As, Be, Cd, Hg, Os, Pb in cored samples by laser ablation. The experimental results showed distinct inhomogeneity in metal distribution. The data suggest that conditions within the concrete structure are favorable for random metal accumulation at certain points. The exact mechanism for this behavior is not clear at this stage and has considerable scope for extended research including modeling and remedial studies.

  8. Environmental toxicity of Chemical Warfare Agents (CWAs) - MicrotoxTM and Spontaneous Locomotor Changes

    DEFF Research Database (Denmark)

    Storgaard, Morten Swayne; Sanderson, Hans; Baatrup, Erik

    After the 2nd World War the CWAs were prohibited by law and 11,000 tonnes of toxic agents were dumped in the Bornholm Basin east of Bornholm. The dumped chemical munitions have not reached attention from politicians and scientists until recently. During earlier projects, such as MERCW (2005...... to be illuminated in which this study hopefully will contribute to. Especially, chronic toxicity needs to be described as this mimics a more environmentally realistic situation. One or two compounds will be accessed based upon various factors such as detection frequencies, found concentrations in both sediment...... to the commercially important cod (Gadus morrhua). The cod migrates down to the seafloor – even crossing the oxycline - where the CWA munitions were dumped. To sum up, this study will obtain novel ecotoxicity data on recently discovered degradation products and assess the potential threat to the commercially...

  9. DETERMINATIONS OF THE ENVIRONMENTAL TOXICITY CHARACTERISTICS OF HAZARDOUS INDUSTRIAL WASTE FROM LANDFILL LEACHATE (CASE STUDY

    Directory of Open Access Journals (Sweden)

    Daniela Dal Molin

    2010-04-01

    Full Text Available The aim of this study was to evaluate the environmental toxicity of hazardous industrial waste from landfill leachate of the one industrial solid waste center from the Rio Grande do Sul state, Brazil. The physical and chemical characteristics, as well as the ecotoxicity with Daphnia magna and toxicity and mutagenicity with Allium cepa were determined. The results of the row leachate sample indicated that the physical and chemical characteristics are compatible with the limit values imputed for treated wastewaters. Absence of acute ecotoxicity was also detected, however a significant (P<0.01 larger frequency of micronuclei was verified when compared with the results of the negative control, suggesting a genotóxico effect of this wast, although not significant alterations in the mitotic index and root growth was observed.

  10. Environmental Pollution, Toxicity Profile and Treatment Approaches for Tannery Wastewater and Its Chemical Pollutants.

    Science.gov (United States)

    Saxena, Gaurav; Chandra, Ram; Bharagava, Ram Naresh

    Leather industries are key contributors in the economy of many developing countries, but unfortunately they are facing serious challenges from the public and governments due to the associated environmental pollution. There is a public outcry against the industry due to the discharge of potentially toxic wastewater having alkaline pH, dark brown colour, unpleasant odour, high biological and chemical oxygen demand, total dissolved solids and a mixture of organic and inorganic pollutants. Various environment protection agencies have prioritized several chemicals as hazardous and restricted their use in leather processing however; many of these chemicals are used and discharged in wastewater. Therefore, it is imperative to adequately treat/detoxify the tannery wastewater for environmental safety. This paper provides a detail review on the environmental pollution and toxicity profile of tannery wastewater and chemicals. Furthermore, the status and advances in the existing treatment approaches used for the treatment and/or detoxification of tannery wastewater at both laboratory and pilot/industrial scale have been reviewed. In addition, the emerging treatment approaches alone or in combination with biological treatment approaches have also been considered. Moreover, the limitations of existing and emerging treatment approaches have been summarized and potential areas for further investigations have been discussed. In addition, the clean technologies for waste minimization, control and management are also discussed. Finally, the international legislation scenario on discharge limits for tannery wastewater and chemicals has also been discussed country wise with discharge standards for pollution prevention due to tannery wastewater.

  11. Environmental impact of toxic elements in red mud studied by fractionation and speciation procedures.

    Science.gov (United States)

    Milačič, Radmila; Zuliani, Tea; Ščančar, Janez

    2012-06-01

    Aluminum (Al) is mostly produced from bauxite ore, which contains up to 70% of Al(2)O(3) (alumina). Before alumina is refined to aluminum metal, it is purified by hot alkaline extraction. As a waste by-product red mud is formed. Due to its high alkalinity and large quantities, it represents a severe disposal problem. In Kidričevo (Slovenia), red mud was washed with water before disposal, and after drying, covered with soil. In Ajka (Hungary), the red mud slurry was collected directly in a containment structure, which burst caused a major accident in October 2010. In the present work the environmental impact of toxic elements in red mud from Kidričevo and Ajka were evaluated by applying a sequential extraction procedure and speciation analysis. The predominant red mud fraction was the insoluble residue; nevertheless, environmental concern was focused on the highly mobile water-soluble fraction of Al and Cr. Al in the water-soluble Ajka mud fraction was present exclusively in form of toxic [Al(OH)(4)](-), while Cr existed in its toxic hexavalent form. Comparative assessment to red mud from Kidričevo (Slovenia) with a lower alkalinity (pH 9) with that from Ajka demonstrated significantly lower Al solubility and the presence of only trace amounts of Cr(VI), confirming that disposal of neutralized mud is environmentally much more acceptable and carries a smaller risk of ecological accidents. Since during the Ajka accident huge amounts of biologically available Al and moderate Cr(VI) concentrations were released into the terrestrial and aquatic environments, monitoring of Al and Cr(VI) set free during remedial actions at the contaminated site is essential. Particular care should be taken to minimize the risk of release of soluble Al species and Cr(VI) into water supplies and surface waters.

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

    OpenAIRE

    Elom, Nwabueze

    2012-01-01

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

  13. Clinch River - Environmental Restoration Program (CR-ERP) study, Ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of January 25-February 1, 1994, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 9.0, Poplar Creek Mile 1.0, and Poplar Creek Mile 2.9 on January 24, 26, and 28. Samples were partitioned (split) and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) to fathead minnows; however, toxicity to daphnids (significantly reduced reproduction) was demonstrated in undiluted samples from Poplar Creek Mile 1.0 in testing conducted by TVA based on hypothesis testing of data. Point estimation (IC{sub 25}) analysis of the data, however, showed no toxicity in PCM 1.0 samples.

  14. Clinch River - Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of April 14-21, 1994, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Poplar Creek Mile 4.3, Poplar Creek Mile 5.1, and Poplar Creek Mile 6.0 on April 13, 15, and 18. Samples were partitioned (split) and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) to daphnids in undiluted samples; however, toxicity to fathead minnows (significantly reduced survival) was demonstrated in undiluted samples from Poplar Creek Miles 4.3 and 6.0 in testing conducted by TVA based on hypothesis testing of data. Daphnid reproduction was significantly less than controls in 50 percent dilutions of samples from Poplar Creek Miles 4.3 and 6.0, while no toxicity to fathead minnows was shown in diluted (50 percent) samples.

  15. The Impact of Pollution Prevention on Toxic Environmental Releases from U.S. Manufacturing Facilities.

    Science.gov (United States)

    Ranson, Matthew; Cox, Brendan; Keenan, Cheryl; Teitelbaum, Daniel

    2015-11-03

    Between 1991 and 2012, the facilities that reported to the U.S. Environmental Protection Agency's Toxic Release Inventory (TRI) Program conducted 370,000 source reduction projects. We use this data set to conduct the first quasi-experimental retrospective evaluation of how implementing a source reduction (pollution prevention) project affects the quantity of toxic chemicals released to the environment by an average industrial facility. We use a differences-in-differences methodology, which measures how implementing a source reduction project affects a facility's releases of targeted chemicals, relative to releases of (a) other untargeted chemicals from the same facility, or (b) the same chemical from other facilities in the same industry. We find that the average source reduction project causes a 9-16% decrease in releases of targeted chemicals in the year of implementation. Source reduction techniques vary in effectiveness: for example, raw material modification causes a large decrease in releases, while inventory control has no detectable effect. Our analysis suggests that in aggregate, the source reduction projects carried out in the U.S. since 1991 have prevented between 5 and 14 billion pounds of toxic releases.

  16. Nanoscale zerovalent iron (nZVI) at environmentally relevant concentrations induced multigenerational reproductive toxicity in Caenorhabditis elegans.

    Science.gov (United States)

    Yang, Ying-Fei; Chen, Pei-Jen; Liao, Vivian Hsiu-Chuan

    2016-05-01

    Nanoscale zerovalent iron (nZVI) is widely used with large scale for environmental remediation for in situ or ex situ applications. The potential impact of nZVI on biota at environmentally relevant concentrations needs to be elucidated. In this study, the reproductive toxicities of three irons species: carboxymethyl cellulose (CMC)-stabilized nZVI, nanoscale iron oxide (nFe3O4), and ferrous ion (Fe(II)aq) in the soil-dwelling nematode Caenorhabditis elegans were examined. In addition, the generational transfer of reproductive toxicity of CMC-nZVI on C. elegans was investigated. The results showed that CMC-nZVI, nFe3O4, and Fe(II)aq did not cause significant mortality after 24 h exposure at the examined concentrations. Reproductive toxicity assays revealed that CMC-nZVI, nFe3O4, and Fe(II)aq significantly decreased offsprings in parental generation (F0) in accompany with the increased intracellular reactive oxygen species (ROS). Furthermore, the reproductive toxicity of CMC-nZVI at environmentally relevant concentrations was transferrable from the F0 to the F1 and F2 generations, but then recovered in the F3 and F4 generations. Further evidence showed that total irons were accumulated in the F0 and F1 generations of C. elegans after CMC-nZVI parental exposure. This study demonstrated that environmentally relevant concentrations of CMC-nZVI induced multigenerational reproductive toxicity which can be ascribed to its high production of ROS in F0 generation, toxicity of Fe(II)aq, and iron accumulation in C. elegans. Since nZVI is widely used for environmental remediation, considering the multigenerational toxicity, this study thus implicates a potential environmental risk of nZVI-induced nanotoxicity in the environment.

  17. Incorporation of gypsum waste in ceramic block production: Proposal for a minimal battery of tests to evaluate technical and environmental viability of this recycling process.

    Science.gov (United States)

    Godinho-Castro, Alcione P; Testolin, Renan C; Janke, Leandro; Corrêa, Albertina X R; Radetski, Claudemir M

    2012-01-01

    Civil engineering-related construction and demolition debris is an important source of waste disposed of in municipal solid waste landfills. After clay materials, gypsum waste is the second largest contributor to the residential construction waste stream. As demand for sustainable building practices grows, interest in recovering gypsum waste from construction and demolition debris is increasing, but there is a lack of standardized tests to evaluate the technical and environmental viability of this solid waste recycling process. By recycling gypsum waste, natural deposits of gypsum might be conserved and high amounts of the waste by-product could be reused in the civil construction industry. In this context, this paper investigates a physical property (i.e., resistance to axial compression), the chemical composition and the ecotoxicological potential of ceramic blocks constructed with different proportions of clay, cement and gypsum waste, and assesses the feasibility of using a minimal battery of tests to evaluate the viability of this recycling process. Consideration of the results for the resistance to axial compression tests together with production costs revealed that the best formulation was 35% of plastic clay, 35% of non-plastic clay, 10% of Portland cement and 20% of gypsum waste, which showed a mean resistance of 4.64MPa. Energy dispersive X-ray spectrometry showed calcium and sulfur to be the main elements, while quartz, gypsum, ettringite and nacrite were the main crystalline compounds found in this formulation. Ecotoxicity tests showed that leachate from this formulation is weakly toxic toward daphnids and bacteria (EC(20%)=69.0 and 75.0, respectively), while for algae and fish the leachate samples were not toxic at the EC(50%) level. Overall, these results show that the addition of 20% of gypsum waste to the ceramic blocks could provide a viable substitute for clay in the ceramics industry and the tests applied in this study proved to be a useful tool

  18. Determination of nanosilver dissolution kinetics and toxicity in an environmentally relevant aqueous medium.

    Science.gov (United States)

    Harmon, Ashley R; Kennedy, Alan J; Poda, Aimee R; Bednar, Anthony J; Chappell, Mark A; Steevens, Jeffery A

    2014-08-01

    Assessing the dissolution of silver nanoparticles (AgNPs) in laboratory test media and in the aquatic environment is critical for determining toxicity. In the present study, the ion-release kinetics for 20-nm, 50-nm, and 80-nm AgNPs in environmentally relevant freshwaters with different electrical conductivity values (30 µS/cm, 150 µS/cm) were examined and related to the associated impact on Daphnia magna. The acute toxicity of the AgNP suspensions to D. magna was assessed after 0 d and 7 d of interaction time between the particles and test media. When 48-h lethal median concentrations were expressed as total silver, D. magna was more sensitive to AgNPs suspended in low ionic strength media relative to higher ionic strength media, with the exception of 50-nm AgNPs suspended in the 150-µS/cm medium. A 3.3-fold increase in hydrodynamic diameter measured by dynamic light scattering and field flow fractionation was observed over time for 20-nm particles in the 150-µS/cm medium, but only a small increase in aggregation size for 50-nm and 80-nm particles (1.4-fold and 1.2-fold increase, respectively) was observed. At a lower conductivity of 30 µS/cm, a 1.7-fold, 1.0-fold, and 1.2-fold increase in aggregation size was observed in the 20-nm, 50-nm, and 80-nm particles, respectively. Thus, the impact of higher conductivity test media on increased aggregation and decreased toxicity (after 7 d) was relatively greater for the smaller (20-nm) AgNP higher compared to the 50-80 nm AgNPs.

  19. Clinch River - Environmental Restoration Program (CR-ERP) pilot study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a pilot study during the week of April 22-29, 1993, prior to initiation of CR-ERP Phase II Sampling and Analysis activities as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 9.0 and Poplar Creek Kilometer 1.6 on April 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA.

  20. Clinch River - Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Russell, C.L.

    1997-06-01

    Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of July 22-29, 1993, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 19.0 and Mile 22.0 on July 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA.

  1. Laboratory Rodent Diets Contain Toxic Levels of Environmental Contaminants: Implications for Regulatory Tests.

    Directory of Open Access Journals (Sweden)

    Robin Mesnage

    Full Text Available The quality of diets in rodent feeding trials is crucial. We describe the contamination with environmental pollutants of 13 laboratory rodent diets from 5 continents. Measurements were performed using accredited methodologies. All diets were contaminated with pesticides (1-6 out of 262 measured, heavy metals (2-3 out of 4, mostly lead and cadmium, PCDD/Fs (1-13 out of 17 and PCBs (5-15 out of 18. Out of 22 GMOs tested for, Roundup-tolerant GMOs were the most frequently detected, constituting up to 48% of the diet. The main pesticide detected was Roundup, with residues of glyphosate and AMPA in 9 of the 13 diets, up to 370 ppb. The levels correlated with the amount of Roundup-tolerant GMOs. Toxic effects of these pollutants on liver, neurodevelopment, and reproduction are documented. The sum of the hazard quotients of the pollutants in the diets (an estimator of risk with a threshold of 1 varied from 15.8 to 40.5. Thus the chronic consumption of these diets can be considered at risk. Efforts toward safer diets will improve the reliability of toxicity tests in biomedical research and regulatory toxicology.

  2. Toxic volatile organic compounds in environmental tobacco smoke: Emission factors for modeling exposures of California populations

    Energy Technology Data Exchange (ETDEWEB)

    Daisey, J.M.; Mahanama, K.R.R.; Hodgson, A.T. [Lawrence Berkeley Lab., CA (United States)

    1994-10-01

    The primary objective of this study was to measure emission factors for selected toxic air contaminants in environmental tobacco smoke (ETS) using a room-sized environmental chamber. The emissions of 23 volatile organic compounds (VOCs), including, 1,3-butadiene, three aldehydes and two vapor-phase N-nitrosamines were determined for six commercial brands of cigarettes and reference cigarette 1R4F. The commercial brands were selected to represent 62.5% of the cigarettes smoked in California. For each brand, three cigarettes were machine smoked in the chamber. The experiments were conducted over four hours to investigate the effects of aging. Emission factors of the target compounds were also determined for sidestream smoke (SS). For almost all target compounds, the ETS emission factors were significantly higher than the corresponding SS values probably due to less favorable combustion conditions and wall losses in the SS apparatus. Where valid comparisons could be made, the ETS emission factors were generally in good agreement with the literature. Therefore, the ETS emission factors, rather than the SS values, are recommended for use in models to estimate population exposures from this source. The variabilities in the emission factors ({mu}g/cigarette) of the selected toxic air contaminants among brands, expressed as coefficients of variation, were 16 to 29%. Therefore, emissions among brands were Generally similar. Differences among brands were related to the smoked lengths of the cigarettes and the masses of consumed tobacco. Mentholation and whether a cigarette was classified as light or regular did not significantly affect emissions. Aging was determined not to be a significant factor for the target compounds. There were, however, deposition losses of the less volatile compounds to chamber surfaces.

  3. Evaluating the environmental impact of artificial sweeteners: a study of their distributions, photodegradation and toxicities.

    Science.gov (United States)

    Sang, Ziye; Jiang, Yanan; Tsoi, Yeuk-Ki; Leung, Kelvin Sze-Yin

    2014-04-01

    While having a long tradition as safe food additives, artificial sweeteners are a newly recognized class of environmental contaminants due to their extreme persistence and ubiquitous occurrence in various aquatic ecosystems. Resistant to wastewater treatment processes, they are continuously introduced into the water environments. To date however, their environmental behavior, fate as well as long term ecotoxicological contributions in our water resources still remain largely unknown. As a first step in the comprehensive study of artificial sweeteners, this work elucidates the geographical/seasonal/hydrological interactions of acesulfame, cyclamate, saccharin and sucralose in an open coast system at an estuarine/marine junction. Higher occurrence of acesulfame (seasonal average: 0.22 μg L(-1)) and sucralose (0.05 μg L(-1)) was found in summer while saccharin (0.11  μg L(-1)) and cyclamate (0.10 μg L(-1)) were predominantly detected in winter. Seasonal observations of the four sweeteners suggest strong connections with the variable chemical resistance among different sweeteners. Our photodegradation investigation further projected the potential impact of persistent acesulfame and sucralose compounds under prolonged exposure to intensive solar irradiation. Real-time observation by UPLC-ESI/MS of the degradation profile in both sweeteners illustrated that formation of new photo by-products under prolonged UV irradiation is highly viable. Interestingly, two groups of kinetically behaved photodegradates were identified for acesulfame, one of which was at least six times more persistent than the parent compound. For the first time, acute toxicity for the degradates of both sweeteners were arbitrarily measured, revealing photo-enhancement factors of 575 and 17.1 for acesulfame and sucralose, respectively. Direct comparison of photodegradation results suggests that the phototoxicity of acesulfame degradation products may impact aquatic ecosystems. In an attempt

  4. The US EPA Geographic Information System for mapping environmental releases of toxic chemical release inventory (TRI) chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Stockwell, J.R.; Sorensen, J.W.; Eckert, J.W. Jr.; Carreras, E.M. (Environmental Protection Agency, Atlanta, GA (United States))

    1993-04-01

    This study characterizes the environmental releases of toxic chemicals of the Toxic Chemical Release Inventory (TRI) in the southeastern United States by using the US Environmental Protection Agency (EPA) Geographic Information System (GIS) to map them. These maps show that the largest quantities of TRI releases in the Southeast are usually near densely populated areas. This GIS mapping approach takes the first steps in defining those areas in the region which may be potential exposure zones and which could be strategic targets for future risk screening efforts in this geographic area. 8 refs., 6 figs., 1 tab.

  5. Amphiphilic block copolymers bearing six-membered ortho ester ring in side chains as potential drug carriers: synthesis, characterization, and in vivo toxicity evaluation.

    Science.gov (United States)

    Luo, Shi; Tao, Yangyang; Tang, Rupei; Wang, Rui; Ji, Weihang; Wang, Chun; Zhao, Youliang

    2014-07-01

    A new type of amphiphilic block copolymers, poly(ethylene glycol)-block-poly(2-methyl-acrylicacid 2-methoxy-5-methyl-[1,3]dioxin-5-ylmethyl ester) (PEG-b-PMME), bearing acid-labile six-membered ortho ester rings in side chains was synthesized by reversible addition-fragmentation chain-transfer polymerization, and the influence of chain length of the hydrophobic PMME block on micelle properties was investigated. The PEG-b-PMME micelles were stable in aqueous buffer at physiological pH with a low critical micelle concentration. Nile Red as a model drug was encapsulated into the micelles to explore the release profiles. The Nile Red-loaded polymeric micelles showed rapid release of Nile Red in weakly acidic environments (pH 5) but slow release under physiological condition (pH 7.4), due to different hydrolysis rate of ortho ester side chains of PEG-b-PMME. The Paclitaxel (PTX)-loaded micelles retained potency in killing lung cancer cells (A549), compared with the free PTX. No obvious toxicity was found in vitro and in vivo after intraperitoneal injection of the micelles, which confirms that the PEG-b-PMME micelles with unique acid-labile characteristic have great potential as nano-scaled carriers for drug delivery.

  6. Study on Testicular Toxicity of 2-Bromopropane, an Environmental Endocrine Disrupter

    Institute of Scientific and Technical Information of China (English)

    李卫华; 范奇元; 张蕴辉; 申立军; 吴晓云; 丁训诚

    2000-01-01

    Objective 2-Bromopropane (2-BP ) is considered as a kind of environmental endocrine disrupters (EDs). Its reproductive and hematopoietic toxicity has aroused the attention of international toxicologists during the past five years. In the present study, we aimed to determine experimentally the testicular toxicity of 2-BP in male rats.Materials & Methods Forty SD male rats were divided into four groups of 10 rats each. The rats were intra-abdominally administered 2-BP once per day for 5 days continuously at the doses of 1 800 mg/kg, 600 mg/kg, 200 mg/kg and normal saline,respectively. The rats were dissected one week after the first administration.Results The body weight, absolute testes weight and relative testes weight of the rats in 1 800 mg/kg dose group decreased significantly with comparison to those of the control group, while the weight of accessory gonads showed no significant change. With the increase of dosage, the seminiferous tubules damage rate aggravated while the ratio of spermatogonia in total germ cells fell with P<0. 05. The seminiferous tubule area of rats in 1 800 mg/kg group also reduced significantly. Under light microscopic examination, the spermatogonia of administered rats showed degeneration and chromatin condensation. The nucleus of spermatocytes appeared hyperchromatic and pyknotic. Obvious testicular damage could be found in rats of high dose group, including large amount of spermatogonia necrosis or loss and reduced spermatocyte number. The electron microscopic findings were similar to those of the light microscopy, except that typical morphological change was found in the middle dose group: the structure of spermatogonia was destroyed, mitochondrion and endoplasmic reticulum scattered outside, nucleus disintegrated; some of the spermatocytes' membrane became unclear,chromatin condensed and cogulation necrosis appeared; the nuclear membrane of round spermatids also showed slight damage.Conclusion The results indicated that testis was

  7. Metabolism of the environmental toxicant benzo(a)pyrene by subcellular fractions of human ovary.

    Science.gov (United States)

    Rekhadevi, P V; Diggs, D L; Huderson, A C; Harris, K L; Archibong, A E; Ramesh, A

    2014-02-01

    Knowledge of the ability of the female reproductive system to metabolize environmental chemicals is critical not only from the standpoint of toxicity but also from infertility risk assessment. Benzo(a)pyrene (BaP) is a toxicant that is released into the environment from automobile exhausts, cigarette smoke, burning of refuse, industrial emissions, and hazardous waste sites. In exposed animals, BaP becomes activated to reactive metabolites that interfere with target organ function and as a consequence cause toxicity. Studies on animal models conducted in our laboratories and those of others have shown that BaP possess endocrine disrupting properties. Thus, this chemical has the potential to cause infertility and cancers in the female genital tract. An understanding of BaP metabolism in the female reproductive system will be of importance in the diagnosis and management of female fertility as well as cancers in the reproductive tissues. Therefore, the objective of our study was to examine the metabolism of BaP by human ovarian subcellular fractions. Human ovary samples (eight individuals) were obtained from postoperative tissue removed from subjects with uterine tumors. Subcellular fractions (nuclear, cytosolic, mitochondrial, and microsomal) were prepared by differential centrifugation. BaP (1 μM and 3 μM) was individually incubated with individual subcellular fractions for 15 min and the products were analyzed by high-performance liquid chromatography. Among the different fractions tested, microsomal BaP metabolism was higher than the rest of the fractions. The BaP metabolites identified were as follows: BaP-9,10-diol, BaP-4,5-diol, BaP-7,8-diol, 9(OH) BaP, 3(OH) BaP, BaP-1,6-dione, BaP-3,6-dione, and BaP-6,12-dione. Of interest was the presence of DNA-reactive metabolites such as BaP-3,6-dione, BaP-6,12-dione, and BaP 7,8-diol, which have been implicated in the causation of infertility and cancer. Our results indicate that women who are exposed to BaP via

  8. Similarities and differences in combined toxicity of sulfonamides and other antibiotics towards bacteria for environmental risk assessment.

    Science.gov (United States)

    Fang, Shuxia; Wang, Dali; Zhang, Xiaoxian; Long, Xi; Qin, Mengnan; Lin, Zhifen; Liu, Ying

    2016-07-01

    Antibiotics as a type of environmental contaminants are typically exposed to chemical mixtures over long periods of time, so chronic combined toxicity is the best way to perform an environmental risk assessment. In this paper, the individual and combined toxicity of sulfonamides (SAs), sulfonamide potentiators (SAPs), and doxycycline hyclate (DH) were tested on gram-positive (Bacillus subtilis, B. subtilis) and gram-negative (Escherichia coli, E. coli) bacteria. The individual toxicity of antibiotics on the two bacteria could be ranked in the same order: SAs antibiotics, which was likely due to both the different abilities of antibiotics to pass through the cell membrane and the varied capacities to bind target proteins between the two bacteria. In addition, the binary mixtures of SAs-SAPs, SAs-DH, and SAs-SAs exhibited synergistic, antagonistic, and additive effects on both of the bacteria but in different magnitudes as represented by the toxicity units (TU). And we found the different TU values were result from the different effective concentrations of antibiotic mixtures based on the approach of molecular docking and quantitative structure-activity relationships (QSARs). Moreover, from the results of risk assessment, it should be noted that the mixture of SAs and other antibiotics may pose a potential environmental risk assessment due to their combined action with the current environmentally realistic concentrations.

  9. Cumulative toxicity of an environmentally relevant mixture of nine regulated disinfection by-products in a multigenerational rat reproductive bioassay

    Science.gov (United States)

    CUMULATIVE TOXICITY OF AN ENVIRONMENTALLY RELEVANT MIXTURE OF NINE REGULATED DISINFECTION BY-PRODUCTS IN A MULTIGENERATIONAL RAT REPRODUCTIVE BIOASSAY J E Simmons, GR. Klinefelter, JM Goldman, AB DeAngelo, DS Best, A McDonald, LF Strader, AS Murr, JD Suarez, MH George, ES Hunte...

  10. Molecular toxicity of cerium oxide nanoparticles to the freshwater alga Chlamydomonas reinhardtii is associated with supra-environmental exposure concentrations.

    Science.gov (United States)

    Taylor, Nadine S; Merrifield, Ruth; Williams, Tim D; Chipman, J Kevin; Lead, Jamie R; Viant, Mark R

    2016-01-01

    Ceria nanoparticles (NPs) are widely used as fuel catalysts and consequently are likely to enter the environment. Their potential impacts on. biota at environmentally relevant concentrations, including uptake and toxicity, remain to be elucidated and quantitative data on which to assess risk are sparse. Therefore, a definitive assessment of the molecular and phenotypic effects of ceria NPs was undertaken, using well-characterised mono-dispersed NPs as their toxicity is likely to be higher, enabling a conservative hazard assessment. Unbiased transcriptomics and metabolomics approaches were used to investigate the potential toxicity of tightly constrained 4-5 nm ceria NPs to the unicellular green alga, Chlamydomonas reinhardtii, a sentinel freshwater species. A wide range of exposure concentrations were investigated from predicted environmental levels, to support hazard assessment, to supra-environmental levels to provide insight into molecular toxicity pathways. Ceria NPs were internalised into intracellular vesicles within C. reinhardtii, yet caused no significant effect on algal growth at any exposure concentration. Molecular perturbations were only detected at supra-environmental ceria NP-concentrations, primarily down-regulation of photosynthesis and carbon fixation with associated effects on energy metabolism. For acute exposures to small mono-dispersed particles, it can be concluded there should be little concern regarding their dispersal into the environment for this trophic level.

  11. Toxic effects of pollutants on the mineralization of substrates at low environmental concentrations in soils, subsoils and sediments

    NARCIS (Netherlands)

    van Beelen P; Fleuren-Kemila AK; Huys MPA; van Mil ACHAM; van Vlaardingen PLA

    1990-01-01

    A novel method is described to study the effect of toxicants on the mineralization of natural and xenobiotic substrates at low concentrations. The method is ecologically relevant because it uses the in situ microflora mineralizing substrates at environmental concentrations and it does not allow unn

  12. Environmental pollution by persistent toxic substances and health risk in an industrial area of China

    Institute of Scientific and Technical Information of China (English)

    Jing Li; Yonglong Lu; Yajuan Shi; Tieyu Wang; Guang Wang; Wei Luo; Wentao Jiao; Chunli Chen; Feng Yan

    2011-01-01

    Soil is an important environmental medium that is closely associated with humans and their health.Despite this,very few studies have measured toxicants in soils,and associated them with health risks in humans.An assessment of health effects from exposure to contaminants in soils surrounding industrial areas of chemical production and storage is important.This article aims at determining pollution characteristics of persistent toxic substances (PTS) in an industrial area in China to unravel the relationship between soil pollution by PTS and human health.One hundred and five soil samples were collected and 742 questionnaires were handed out to residents living in and around an industrial area around Bohai Bay,Tianjin in Northern China.Concentrations of organochlorine pesticides and polycyclic aromatic hydrocarbons (PAHs) were determined in soil.Mann-Whitney U and binary multivariate nonconditional logistic regression models were employed to analyze the relationship between health indicators of local residents and contaminant levels.Odds ratio (OR) and a 95% confidence interval (CI) for health incidences were also calculated.The average concentrations of DDT (73.9 rig/g),HCH (654 ng/g) and PAHs (1225 ng/g) were relatively high in the industrial area.Residents living in the chemical industry parks were exposed to a higher levels of PTS than those living outside the chemical industry parks.This exposure was associated with a higher risk of breast cancer (OR 1.87,95% CI 0.12-30.06),stomach cancer (OR 1.87,95% CI 0.26-13.41),dermatitis (OR 1.72,95% CI 1.05-2.80),gastroenteritis (OR 1.59,95% CI 0.94-2.68),and pneumonia (OR 1.05,95% CI 0.58-1.89).

  13. Environmental Contaminants and microRNA Regulation: Transcription Factors as Regulators of Toxicant-Altered microRNA Expression

    Science.gov (United States)

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

    2016-01-01

    MicroRNAs (miRNAs) regulate gene expression by binding mRNA transcripts 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 in silico bioinformatic analysis 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. PMID:27292125

  14. Executive Order 12898 and Social, Economic, and Sociopolitical Factors Influencing Toxic Release Inventory Facility Location in EPA Region 6: A Multi-Scale Spatial Assessment of Environmental Justice

    Science.gov (United States)

    Moore, Andrea Lisa

    2013-01-01

    Toxic Release Inventory facilities are among the many environmental hazards shown to create environmental inequities in the United States. This project examined four factors associated with Toxic Release Inventory, specifically, manufacturing facility location at multiple spatial scales using spatial analysis techniques (i.e., O-ring statistic and…

  15. NASA Environmentally Responsible Aviation's Highly-Loaded Front Block Compressor Demonstration

    Science.gov (United States)

    Celestina, Mark

    2016-01-01

    This presentation will detail the work done to improve thermal efficiency in the compression process of a gas turbine engine for aircraft applications under NASAs Environmentally Responsible Aviation Project. The talk will present the goals and objectives of the work and show the activity of both Phase 1 and Phase 2 tests and analysis. The summary shows the projected fuel burn savings achieved through system studies.

  16. Exacerbated Airway Toxicity of Environmental Oxidant Ozone in Mice Deficient in Nrf2

    Directory of Open Access Journals (Sweden)

    Hye-Youn Cho

    2013-01-01

    Full Text Available Ozone (O3 is a strong oxidant in air pollution that has harmful effects on airways and exacerbates respiratory disorders. The transcription factor Nrf2 protects airways from oxidative stress through antioxidant response element-bearing defense gene induction. The present study was designed to determine the role of Nrf2 in airway toxicity caused by inhaled O3 in mice. For this purpose, Nrf2-deficient (Nrf2-/- and wild-type (Nrf2+/+ mice received acute and subacute exposures to O3. Lung injury was determined by bronchoalveolar lavage and histopathologic analyses. Oxidation markers and mucus hypersecretion were determined by ELISA, and Nrf2 and its downstream effectors were determined by RT-PCR and/or Western blotting. Acute and sub-acute O3 exposures heightened pulmonary inflammation, edema, and cell death more severely in Nrf2-/- mice than in Nrf2+/+ mice. O3 caused bronchiolar and terminal bronchiolar proliferation in both genotypes of mice, while the intensity of compensatory epithelial proliferation, bronchial mucous cell hyperplasia, and mucus hypersecretion was greater in Nrf2-/- mice than in Nrf2+/+ mice. Relative to Nrf2+/+, O3 augmented lung protein and lipid oxidation more highly in Nrf2-/- mice. Results suggest that Nrf2 deficiency exacerbates oxidative stress and airway injury caused by the environmental pollutant O3.

  17. Bioassay standardization for the detection of allelopathic compounds and environmental toxicants using lettuce

    Directory of Open Access Journals (Sweden)

    Mateus Salomão Simões

    2013-09-01

    Full Text Available The purpose of this study was to assess different experimental conditions to determine a protocol for bioassays based on seed germination and early seedling growth using lettuce (Lactuca sativa L. cv. Grand Rapids as indicator species. This protocol aims to provide support for the standardization of assays of various chemicals such as allelochemicals and environmental toxicants. The following tests were performed: time of germination, temperature, light, solution volume and Petri dish size. For each test (except for time of germination, the influence of the conditions investigated was determined by the endpoints germination percentage, germination speed index, root length, seedling fresh weight and total dry weight. The results showed that variations in the methods altered the results. It is recommended that bioassays using L. sativa L. cv. Grand Rapids be carried out for a minimum period of four days for assessments of both germination and initial growth and that the experimental conditions include a temperature of 20°C, 90-mm Petri dishes or larger, 0.1 mL cypsela solution, and continuous light or 12-hour photoperiod.

  18. Hair as a biological indicator of drug use, drug abuse or chronic exposure to environmental toxicants.

    Science.gov (United States)

    Boumba, Vassiliki A; Ziavrou, Kallirroe S; Vougiouklakis, Theodore

    2006-01-01

    In recent years hair has become a fundamental biological specimen, alternative to the usual samples blood and urine, for drug testing in the fields of forensic toxicology, clinical toxicology and clinical chemistry. Moreover, hair-testing is now extensively used in workplace testing, as well as, on legal cases, historical research etc. This article reviews methodological and practical issues related to the application of hair as a biological indicator of drug use/abuse or of chronic exposure to environmental toxicants. Hair structure and the mechanisms of drug incorporation into it are commented. The usual preparation and extraction methods as well as the analytical techniques of hair samples are presented and commented on. The outcomes of hair analysis have been reviewed for the following categories: drugs of abuse (opiates, cocaine and related, amphetamines, cannabinoids), benzodiazepines, prescribed drugs, pesticides and organic pollutants, doping agents and other drugs or substances. Finally, the specific purpose of the hair testing is discussed along with the interpretation of hair analysis results regarding the limitations of the applied procedures.

  19. Environmental conditions enhance toxicant effects in larvae of the ground beetle Pterostichus oblongopunctatus (Coleoptera: Carabidae)

    Energy Technology Data Exchange (ETDEWEB)

    Bednarska, Agnieszka J., E-mail: a.bednarska@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)

    2009-05-15

    The wide geographical distribution of ground beetles Pterostichus oblongopunctatus makes them very likely to be exposed to several environmental stressors at the same time. These could include both climatic stress and exposure to chemicals. Our previous studies demonstrated that the combined effect of nickel (Ni) and chlorpyrifos (CHP) was temperature (T)-dependent in adult P. oblongopunctatus. Frequently the different developmental stages of an organism are differently sensitive to single stressors, and for a number of reasons, such as differences in exposure routes, their interactions may also take different forms. Because of this, we studied the effects of the same factors on the beetle larvae. The results showed that all factors, as well as their interactions, influenced larvae survival. The synergistic effect of Ni and CPF was temperature-dependent and the effect of Ni x T interaction on the proportion of emerged imagines indicated stronger toxicity of Ni at 25 deg. C than at 10 deg. C. - Combined negative effects of nickel and chlorpyrifos on carabid beetles depend on ambient temperature.

  20. Zebrafish as a Vertebrate Model System to Evaluate Effects of Environmental Toxicants on Cardiac Development and Function

    Science.gov (United States)

    Sarmah, Swapnalee; Marrs, James A.

    2016-01-01

    Environmental pollution is a serious problem of the modern world that possesses a major threat to public health. Exposure to environmental pollutants during embryonic development is particularly risky. Although many pollutants have been verified as potential toxicants, there are new chemicals in the environment that need assessment. Heart development is an extremely sensitive process, which can be affected by environmentally toxic molecule exposure during embryonic development. Congenital heart defects are the most common life-threatening global health problems, and the etiology is mostly unknown. The zebrafish has emerged as an invaluable model to examine substance toxicity on vertebrate development, particularly on cardiac development. The zebrafish offers numerous advantages for toxicology research not found in other model systems. Many laboratories have used the zebrafish to study the effects of widespread chemicals in the environment on heart development, including pesticides, nanoparticles, and various organic pollutants. Here, we review the uses of the zebrafish in examining effects of exposure to external molecules during embryonic development in causing cardiac defects, including chemicals ubiquitous in the environment and illicit drugs. Known or potential mechanisms of toxicity and how zebrafish research can be used to provide mechanistic understanding of cardiac defects are discussed. PMID:27999267

  1. Zebrafish as a Vertebrate Model System to Evaluate Effects of Environmental Toxicants on Cardiac Development and Function

    Directory of Open Access Journals (Sweden)

    Swapnalee Sarmah

    2016-12-01

    Full Text Available Environmental pollution is a serious problem of the modern world that possesses a major threat to public health. Exposure to environmental pollutants during embryonic development is particularly risky. Although many pollutants have been verified as potential toxicants, there are new chemicals in the environment that need assessment. Heart development is an extremely sensitive process, which can be affected by environmentally toxic molecule exposure during embryonic development. Congenital heart defects are the most common life-threatening global health problems, and the etiology is mostly unknown. The zebrafish has emerged as an invaluable model to examine substance toxicity on vertebrate development, particularly on cardiac development. The zebrafish offers numerous advantages for toxicology research not found in other model systems. Many laboratories have used the zebrafish to study the effects of widespread chemicals in the environment on heart development, including pesticides, nanoparticles, and various organic pollutants. Here, we review the uses of the zebrafish in examining effects of exposure to external molecules during embryonic development in causing cardiac defects, including chemicals ubiquitous in the environment and illicit drugs. Known or potential mechanisms of toxicity and how zebrafish research can be used to provide mechanistic understanding of cardiac defects are discussed.

  2. Environmental levels, toxicity and human exposure to tributyltin (TBT)-contaminated marine environment. a review. b_antizar@hotmail.com.

    Science.gov (United States)

    Antizar-Ladislao, Blanca

    2008-02-01

    Tributyltin (TBT) is a toxic chemical used for various industrial purposes such as slime control in paper mills, disinfection of circulating industrial cooling waters, antifouling agents, and the preservation of wood. Due to its widespread use as an antifouling agent in boat paints, TBT is a common contaminant of marine and freshwater ecosystems exceeding acute and chronic toxicity levels. TBT is the most significant pesticide in marine and freshwaters in Europe and consequently its environmental level, fate, toxicity and human exposure are of current concern. Thus, the European Union has decided to specifically include TBT compounds in its list of priority compounds in water in order to control its fate in natural systems, due to their toxic, persistent, bioaccumulative and endocrine disruptive characteristics. Additionally, the International Maritime Organization has called for a global treaty that bans the application of TBT-based paints starting 1 of January 2003, and total prohibition by 1 of January 2008. This paper reviews the state of the science regarding TBT, with special attention paid to the environmental levels, toxicity, and human exposure. TBT compounds have been detected in a number of environmental samples. In humans, organotin compounds have been detected in blood and in the liver. As for other persistent organic pollutants, dietary intake is most probably the main route of exposure to TBT compounds for the general population. However, data concerning TBT levels in foodstuffs are scarce. It is concluded that investigations on experimental toxicity, dietary intake, potential human health effects and development of new sustainable technologies to remove TBT compounds are clearly necessary.

  3. Realistic environmental mixtures of micropollutants in surface, drinking, and recycled water: herbicides dominate the mixture toxicity toward algae.

    Science.gov (United States)

    Tang, Janet Y M; Escher, Beate I

    2014-06-01

    Mixture toxicity studies with herbicides have focused on a few priority components that are most likely to cause environmental impacts, and experimental mixtures were often designed as equipotent mixtures; however, real-world mixtures are made up of chemicals with different modes of toxic action at arbitrary concentration ratios. The toxicological significance of environmentally realistic mixtures has only been scarcely studied. Few studies have simultaneously compared the mixture effect of water samples with designed reference mixtures comprised of the ratios of analytically detected concentrations in toxicity tests. In the present study, the authors address the effect of herbicides and other chemicals on inhibition of photosynthesis and algal growth rate. The authors tested water samples including secondary treated wastewater effluent, recycled water, drinking water, and storm water in the combined algae assay. The detected chemicals were mixed in the concentration ratios detected, and the biological effects of the water samples were compared with the designed mixtures of individual detected chemicals to quantify the fraction of effect caused by unknown chemicals. The results showed that herbicides dominated the algal toxicity in these environmentally realistic mixtures, and the contribution by the non-herbicides was negligible. A 2-stage model, which used concentration addition within the groups of herbicides and non-herbicides followed by the model of independent action to predict the mixture effect of the two groups, could predict the experimental mixture toxicity effectively, but the concentration addition model for herbicides was robust and sufficient for complex mixtures. Therefore, the authors used the bioanalytical equivalency concept to derive effect-based trigger values for algal toxicity for monitoring water quality in recycled and surface water. All water samples tested would be compliant with the proposed trigger values associated with the

  4. Integrated assessment of behavioral and environmental risk factors for Lyme disease infection on Block Island, Rhode Island.

    Directory of Open Access Journals (Sweden)

    Casey Finch

    Full Text Available Peridomestic exposure to Borrelia burgdorferi-infected Ixodes scapularis nymphs is considered the dominant means of infection with black-legged tick-borne pathogens in the eastern United States. Population level studies have detected a positive association between the density of infected nymphs and Lyme disease incidence. At a finer spatial scale within endemic communities, studies have focused on individual level risk behaviors, without accounting for differences in peridomestic nymphal density. This study simultaneously assessed the influence of peridomestic tick exposure risk and human behavior risk factors for Lyme disease infection on Block Island, Rhode Island. Tick exposure risk on Block Island properties was estimated using remotely sensed landscape metrics that strongly correlated with tick density at the individual property level. Behavioral risk factors and Lyme disease serology were assessed using a longitudinal serosurvey study. Significant factors associated with Lyme disease positive serology included one or more self-reported previous Lyme disease episodes, wearing protective clothing during outdoor activities, the average number of hours spent daily in tick habitat, the subject's age and the density of shrub edges on the subject's property. The best fit multivariate model included previous Lyme diagnoses and age. The strength of this association with previous Lyme disease suggests that the same sector of the population tends to be repeatedly infected. The second best multivariate model included a combination of environmental and behavioral factors, namely hours spent in vegetation, subject's age, shrub edge density (increase risk and wearing protective clothing (decrease risk. Our findings highlight the importance of concurrent evaluation of both environmental and behavioral factors to design interventions to reduce the risk of tick-borne infections.

  5. Toxicity assessment through multiple endpoint bioassays in soils posing environmental risk according to regulatory screening values.

    Science.gov (United States)

    Rodriguez-Ruiz, A; Asensio, V; Zaldibar, B; Soto, M; Marigómez, I

    2014-01-01

    Toxicity profiles of two soils (a brownfield in Legazpi and an abandoned iron mine in Zugaztieta; Basque Country) contaminated with several metals (As, Zn, Pb and Cu in Legazpi; Zn, Pb, Cd and Cu in Zugaztieta) and petroleum hydrocarbons (in Legazpi) were determined using a multi-endpoint bioassay approach. Investigated soils exceeded screening values (SVs) of regulatory policies in force (Basque Country; Europe). Acute and chronic toxicity bioassays were conducted with a selected set of test species (Vibrio fischeri, Dictyostelium discoideum, Lactuca sativa, Raphanus sativus and Eisenia fetida) in combination with chemical analysis of soils and elutriates, as well as with bioaccumulation studies in earthworms. The sensitivity of the test species and the toxicity endpoints varied depending on the soil. It was concluded that whilst Zugaztieta soil showed very little or no toxicity, Legazpi soil was toxic according to almost all the toxicity tests (solid phase Microtox, D. discoideum inhibition of fruiting body formation and developmental cycle solid phase assays, lettuce seed germination and root elongation test, earthworm acute toxicity and reproduction tests, D. discoideum cell viability and replication elutriate assays). Thus, albeit both soils had similar SVs, their ecotoxicological risk, and therefore the need for intervening, was different for each soil as unveiled after toxicity profiling based on multiple endpoint bioassays. Such a toxicity profiling approach is suitable to be applied for scenario-targeted soil risk assessment in those cases where applicable national/regional soil legislation based on SVs demands further toxicity assessment.

  6. Assessment of the toxicity of a substance under Canadian environmental protection act, a case study. Polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Nadon, B.; Germain, A.; Coillie, R. van [Environment Canada, Montreal (Canada)

    1995-12-31

    The Canadian Environmental Protection Act (CEPA) proclaimed in 1988 requires the Canadian Ministers of the Environment and of National Health and Welfare to assess the toxicity of different substances. A Priority Substances List containing 44 substances was developed and their assessments had to determine if they were `toxic`, according to the CEPA definition. This definition states that `a substance is toxic if it is entering or may enter the environment in a quantity or concentration or under conditions (a) having or that may have an immediate or long-term harmful effect on the environment, (b) constituting or that may constitute a danger to the environment on which human life depends; or (c) constituting or that may constitute a danger in Canada to human life of health.` This presentation use the assessment of the polycyclic aromatic hydrocarbons (PAHs) as an example of this procedure. (author)

  7. Toxicity of iron-based nanoparticles to green algae: Effects of particle size, crystal phase, oxidation state and environmental aging.

    Science.gov (United States)

    Lei, Cheng; Zhang, Luqing; Yang, Kun; Zhu, Lizhong; Lin, Daohui

    2016-11-01

    With the increasing environmental application and discharge of iron-based nanoparticles (NPs), a comprehensive understanding of their fate and ecotoxicological effect in the aquatic environment is very urgent. In this study, toxicities of 4 zero-valent iron NPs (nZVI) of different sizes, 2 Fe2O3 NPs of different crystal phases, and 1 type of Fe3O4 NPs to a green alga (Chlorella pyrenoidosa) were investigated, with a focus on the effects of particle size, crystal phase, oxidation state, and environmental aging. Results show that the algal growth inhibition of nZVI increased significantly with decreasing particle size; with similar particle sizes (20-30 nm), the algal growth inhibition decreased with oxidation of the NPs with an order of nZVI > Fe3O4 NPs > Fe2O3 NPs, and α-Fe2O3 NPs presented significantly higher toxicity than γ-Fe2O3 NPs. The NP-induced oxidative stress was the main toxic mechanism, which could explain the difference in algal toxicity of the NPs. The NP-cell heteroagglomeration and physical interactions also contributed to the nanotoxicity, whereas the effect of NP dissolution was negligible. The aging in distilled water and 3 surface water samples for 3 months increased surface oxidation of the iron-based NPs especially nZVI, which decreased the toxicity to algae. These findings will be helpful for the understanding of the fate and toxicity of iron-based NPs in the aquatic environment.

  8. Molecular control of TiO₂-NPs toxicity formation at predicted environmental relevant concentrations by Mn-SODs proteins.

    Directory of Open Access Journals (Sweden)

    Yinxia Li

    Full Text Available With growing concerns of the safety of nanotechnology, the in vivo toxicity of nanoparticles (NPs at environmental relevant concentrations has drawn increasing attentions. We investigated the possible molecular mechanisms of titanium nanoparticles (Ti-NPs in the induction of toxicity at predicted environmental relevant concentrations. In nematodes, small sizes (4 nm and 10 nm of TiO₂-NPs induced more severe toxicities than large sizes (60 nm and 90 nm of TiO₂-NPs on animals using lethality, growth, reproduction, locomotion behavior, intestinal autofluorescence, and reactive oxygen species (ROS production as endpoints. Locomotion behaviors could be significantly decreased by exposure to 4-nm and 10-nm TiO₂-NPs at concentration of 1 ng/L in nematodes. Among genes required for the control of oxidative stress, only the expression patterns of sod-2 and sod-3 genes encoding Mn-SODs in animals exposed to small sizes TiO₂-NPs were significantly different from those in animals exposed to large sizes of TiO₂-NPs. sod-2 and sod-3 gene expressions were closely correlated with lethality, growth, reproduction, locomotion behavior, intestinal autofluorescence, and ROS production in TiO₂-NPs-exposed animals. Ectopically expression of human and nematode Mn-SODs genes effectively prevented the induction of ROS production and the development of toxicity of TiO₂-NPs. Therefore, the altered expression patterns of Mn-SODs may explain the toxicity formation for different sizes of TiO₂-NPs at predicted environmental relevant concentrations. In addition, we demonstrated here a strategy to investigate the toxicological effects of exposure to NPs upon humans by generating transgenic strains in nematodes for specific human genes.

  9. Temporal dissolution of potentially toxic elements from silver smelting slag by synthetic environmental solutions.

    Science.gov (United States)

    Ash, Christopher; Borůvka, Luboš; Tejnecký, Václav; Šebek, Ondřej; Nikodem, Antonín; Drábek, Ondřej

    2013-11-15

    Waste slag which is created during precious metal smelting contains high levels of potentially toxic elements (PTE) which can be mobilised from unconfined deposits into the local environment. This paper examines the extractability of selected PTE (Pb, Zn, Cd, Mn) from slag samples by synthetic solutions designed to replicate those in the environment. Extracting agents were used to replicate potential leaching scenarios which are analogous to natural chemical weathering. Slag was submersed in a rainwater simulation solution (RSS), weak citric acid solution (representing rhizosphere secretions) and control solutions (deionised water) for a one month period with solution analyses made at intervals of 1, 24, 168 and 720 h. In 1 mM citric acid, dissolution of Cd and Zn showed little change with time, although for Zn the initial dissolution was considerable. Lead in citric acid was characterized by overall poor extractability. Mn solubility increased until an equilibrium state occurred within 24 h. The solubility of studied metals in citric acid can be characterized by a short time to equilibrium. RSS proved to be an effective solvent that, unlike citric acid solution, extracted increasing concentrations of Cd, Mn and Zn with time. Solubility of Pb in RSS was again very low. When taken as a proportion of a single 2 M HNO3 extraction which was applied to slag samples, Cd was the element most readily leached into RSS and control samples. In both studied solvents, slag heterogeneity is prominent in the case of Cd and Zn solubility. Contact time with solvent appears to be an important variable for the release of PTE from slag into solution. The purpose of this study was to provide insight into the environmental chemical dissolution of PTE from slag, which causes their enrichment in surrounding soils and surface waters.

  10. Epigenetic mechanisms of mouse interstrain variability in genotoxicity of the environmental toxicant 1,3-butadiene.

    Science.gov (United States)

    Koturbash, Igor; Scherhag, Anne; Sorrentino, Jessica; Sexton, Kenneth; Bodnar, Wanda; Swenberg, James A; Beland, Frederick A; Pardo-Manuel Devillena, Fernando; Rusyn, Ivan; Pogribny, Igor P

    2011-08-01

    1,3-Butadiene (BD) is a common environmental contaminant classified as "carcinogenic to humans." Formation of BD-induced DNA adducts plays a major role in its carcinogenicity. BD is also an epigenotoxic agent (i.e., it affects DNA and histone methylation in the liver). We used a panel of genetically diverse inbred mice (NOD/LtJ, CAST/EiJ, A/J, WSB/EiJ, PWK/PhJ, C57BL/6J, and 129S1/SvImJ) to assess whether BD-induced genotoxic and epigenotoxic events may be subject to interstrain differences. Mice (male, 7 weeks) were exposed via inhalation to 0 or 625 ppm BD for 6 h/day and 5 days/week for 2 weeks and liver BD-DNA adducts, epigenetic alterations, and liver toxicity were assessed. N-7-(2,3,4-trihydroxybut-1-yl)-guanine adducts were detected in all strains after exposure, yet BD-induced DNA damage in CAST/EiJ mice was two to three times lower. Epigenetic effects of BD were most prominent in C57BL/6J mice where loss of global DNA methylation and loss of trimethylation of histone H3 lysine 9, histone H3 lysine 27, and histone H4 lysine 20, accompanied by dysregulation of liver gene expression indicative of hepatotoxicity, were found. Interestingly, we observed an increase in histone methylation in the absence of changes in gene expression and DNA methylation in CAST/EiJ strain. We hypothesized that mitigated genotoxicity of BD in CAST/EiJ mice may be due to chromatin condensation. Indeed, we show that in response to BD exposure, chromatin condensation occurs in CAST/EiJ, whereas the opposite effect is observed in C57BL/6J mice. These findings demonstrate that interstrain susceptibility to genotoxicity by a well-known environmental carcinogen may be due to strain-specific epigenetic events in response to the exposure.

  11. Hazard screening of chemical releases and environmental equity analysis of populations proximate to toxic release inventory facilities in Oregon.

    Science.gov (United States)

    Neumann, C M; Forman, D L; Rothlein, J E

    1998-04-01

    A comprehensive approach using hazard screening, demographic analysis, and a geographic information system (GIS) for mapping is employed to address environmental equity issues in Oregon. A media-specific chronic toxicity index [or chronic index (CI)] was used to compare environmental chemical releases reported in the EPA's Toxic Chemical Release Inventory (TRI) database. In 1992, 254 facilities reportedly released more than 40 million pounds of toxic chemicals directly into the environment on-site or transferred them to sewage treatment plants or other off-site facilities for disposal and recycling. For each reported on-site TRI chemical release, a CI based on oral toxicity factors and total mass was calculated. CIs were aggregated on a media-, facility-, and chemical-specific basis. Glycol ethers, nickel, trichloroethylene, chloroform, and manganese were ranked as the top five chemicals released statewide based on total CI. In contrast, based on total mass, methanol, nickel, ammonia, acetone, and toluene were identified as the top five TRI chemicals released in Oregon. TRI facility rankings were related to the demographics and household income of surrounding neighborhoods using bivariate GIS mapping and statistical analysis. TRI facilities were disproportionately located in racial and ethnic minority neighborhoods. They were also located in areas with lower incomes compared to those in the surrounding county. No relationship was observed between the hazard ranking of the TRI facilities overall and socioeconomic characteristics of the community in which they were located.

  12. Dynamical analysis of a five-dimensioned chemostat model with impulsive diffusion and pulse input environmental toxicant

    Energy Technology Data Exchange (ETDEWEB)

    Jiao Jianjun, E-mail: jiaojianjun05@126.co [Guizhou Key Laboratory of Economic System Simulation, Guizhou College of Finance and Economics, Guiyang 550004 (China); Ye Kaili [School of Economics and Management, Xinyang Normal University, Xinyang 464000, Henan (China); Chen Lansun [Institute of Mathematics, Academy of Mathematics and System Sciences, Beijing 100080 (China)

    2011-01-15

    Research Highlights: This work improves on existing chemostat models. The proposed model accounts for natural phenomena. This work improves on the existing mathematical methods. - Abstract: In this paper, we consider a five-dimensioned chemostat model with impulsive diffusion and pulse input environmental toxicant. Using the discrete dynamical system determined by the stroboscopic map, we obtain a microorganism-extinction periodic solution. Further, it is globally asymptotically stable. The permanent condition of the investigated system is also analyzed by the theory on impulsive differential equation. Our results reveal that the chemostat environmental changes play an important role on the outcome of the chemostat.

  13. 75 FR 43172 - Board of Scientific Counselors, National Center for Environmental Health/Agency for Toxic...

    Science.gov (United States)

    2010-07-23

    ... HUMAN SERVICES Agency for Toxic Substances and Disease Board of Scientific Counselors, National Center... of Charter Renewal This gives notice under the Federal Advisory Committee Act (Pub. L. 92-463) of October 6, 1972, that the Board of Scientific Counselors, Agency for Toxic Substances and Disease...

  14. Parametric Analysis of the Exergoeconomic Operation Costs, Environmental and Human Toxicity Indexes of the MF501F3 Gas Turbine

    Directory of Open Access Journals (Sweden)

    Edgar Vicente Torres-González

    2016-08-01

    Full Text Available This work presents an energetic, exergoeconomic, environmental, and toxicity analysis of the simple gas turbine M501F3 based on a parametric analysis of energetic (thermal efficiency, fuel and air flow rates, and specific work output, exergoeconomic (exergetic efficiency and exergoeconomic operation costs, environmental (global warming, smog formation, acid rain indexes, and human toxicity indexes, by taking the compressor pressure ratio and the turbine inlet temperature as the operating parameters. The aim of this paper is to provide an integral, systematic, and powerful diagnostic tool to establish possible operation and maintenance actions to improve the gas turbine’s exergoeconomic, environmental, and human toxicity indexes. Despite the continuous changes in the price of natural gas, the compressor, combustion chamber, and turbine always contribute 18.96%, 53.02%, and 28%, respectively, to the gas turbine’s exergoeconomic operation costs. The application of this methodology can be extended to other simple gas turbines using the pressure drops and isentropic efficiencies, among others, as the degradation parameters, as well as to other energetic systems, without loss of generality.

  15. Evaluate the potential environmental toxicity of quantum dots on ciliated protozoa by microcalorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Qi [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China); State Key Laboratory of Virology, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China); Huang, Shan, E-mail: huangs@whu.edu.cn [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China); State Key Laboratory of Virology, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China); Su, Wei [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China); Li, Peiyuan [College of Pharmacy, Guangxi Traditional Chinese Medical University, Nanning 530001 (China); Liang, Zuocui; Ou, Jianzhen; Ma, Jianqiang [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China); Liu, Yi, E-mail: prof.liuyi@263.net [State Key Laboratory of Virology, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China)

    2012-11-10

    Highlights: Black-Right-Pointing-Pointer The toxic effects of QDs to T. thermophila BF{sub 5} using a TAM air microcalorimeter. Black-Right-Pointing-Pointer QDs were acutely toxic for T. thermophila BF{sub 5} growth in a dose-dependent manner. Black-Right-Pointing-Pointer The toxicity of different ligands-capped QDs on T. thermophila BF{sub 5} was investigated. Black-Right-Pointing-Pointer QDs could be ingested by cells and affect the morphology of T. thermophila BF{sub 5}. - Abstract: In the present study, we evaluated the toxic effects of mercaptoacetic acid (MAA)-capped CdSe QDs and CdSe/ZnS QDs to particle-ingesting model ciliated protozoa Tetrahymena thermophila BF{sub 5} (T. thermophila BF{sub 5}) by using a TAM air isothermal microcalorimeter. These results suggested that both MAA-CdSe QDs and MAA-CdSe/ZnS QDs were indeed acutely toxic for T. thermophila BF{sub 5} growth in a dose-dependent manner, and the toxicities of both MAA-CdSe QDs and MAA-CdSe/ZnS QDs increased dramatically after UV irradiation due to the liberation of more toxic Cd{sup 2+}, which indicated that the toxicity of MAA-CdSe/ZnS QDs was less than that of MAA-CdSe QDs. Furthermore, the toxicity of different ligands-capped CdSe/ZnS QDs on T. thermophila BF{sub 5} was also investigated. The uptake of MAA-CdSe/ZnS QDs and adenosine 5 Prime -monophosphate (AMP)-CdSe/ZnS QDs by cells and the morphological change during the process of T. thermophila BF{sub 5} growth incubated with these QDs were further studied by fluorescence inverted microscopy.

  16. Anodonta imbecillis copper sulfate reference toxicant test, Clinch River - Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Reference toxicant testing using juvenile freshwater mussels was conducted as part of the CR-ERP biomonitoring study of Clinch River sediments to assess the sensitivity of test organisms and the overall performance of the test. Tests were conducted using moderately hard synthetic water spiked with known concentrations of copper as copper sulfate. Toxicity testing of copper sulfate reference toxicant was conducted from May 12-21, 1993. The organisms used for testing were juvenile fresh-water mussels (Anodonta imbecillis). Results from this test showed an LC{sub 50} value of 1.12 mg Cu/L which is lower than the value of 2.02 mg Cu/L obtained in a previous test. Too few tests have been conducted with copper as the toxicant to determine a normal range of values.

  17. Environmental interactions with the toxicity of plant essential oils to the poultry red mite Dermanyssus gallinae.

    Science.gov (United States)

    George, D R; Sparagano, O A E; Port, G; Okello, E; Shiel, R S; Guy, J H

    2010-03-01

    The toxicity of a range of plant essential oils to the poultry red mite, Dermanyssus gallinae (De Geer) (Acari: Dermanyssidae), a serious ectoparasitic pest of laying hens throughout Europe and elsewhere, was assessed in the laboratory. Dermanyssus gallinae may cause losses in egg production, anaemia and, in extreme cases, death of hens. With changes in legislation and consumer demand, alternatives to synthetic acaricides are needed to manage this pest. Fifty plant essential oils were selected for their toxicity to arthropods reported in the literature. Twenty-four of these essential oils were found to kill > 75% of adult D. gallinae in contact toxicity tests over a 24-h period at a rate of 0.21 mg/cm(2). Subsequent testing at lower rates showed that the essential oils of cade, manuka and thyme were especially toxic to adult D. gallinae. The toxicity of the seven most acaricidal essential oils was found to be stable at different temperatures likely to be encountered in commercial poultry housing (15 degrees C, 22 degrees C and 29 degrees C), although results suggest that humidity and dust might influence the toxicity of some of the oils tested. The toxicity of clove bud essential oil to D. gallinae, for example, was increased at high humidity and dust levels compared with ambient levels. The results suggest that certain essential oils may make effective botanical pesticides for use against D. gallinae, although it is likely that issues relating to the consistency of the toxic effect of some oils will determine which oils will be most effective in practice.

  18. Distributed Structure Searchable Toxicity

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Distributed Structure Searchable Toxicity (DSSTox) online resource provides high quality chemical structures and annotations in association with toxicity data....

  19. A review of research trends in physiological abnormalities in autism spectrum disorders: immune dysregulation, inflammation, oxidative stress, mitochondrial dysfunction and environmental toxicant exposures.

    Science.gov (United States)

    Rossignol, D A; Frye, R E

    2012-04-01

    Recent studies have implicated physiological and metabolic abnormalities in autism spectrum disorders (ASD) and other psychiatric disorders, particularly immune dysregulation or inflammation, oxidative stress, mitochondrial dysfunction and environmental toxicant exposures ('four major areas'). The aim of this study was to determine trends in the literature on these topics with respect to ASD. A comprehensive literature search from 1971 to 2010 was performed in these four major areas in ASD with three objectives. First, publications were divided by several criteria, including whether or not they implicated an association between the physiological abnormality and ASD. A large percentage of publications implicated an association between ASD and immune dysregulation/inflammation (416 out of 437 publications, 95%), oxidative stress (all 115), mitochondrial dysfunction (145 of 153, 95%) and toxicant exposures (170 of 190, 89%). Second, the strength of evidence for publications in each area was computed using a validated scale. The strongest evidence was for immune dysregulation/inflammation and oxidative stress, followed by toxicant exposures and mitochondrial dysfunction. In all areas, at least 45% of the publications were rated as providing strong evidence for an association between the physiological abnormalities and ASD. Third, the time trends in the four major areas were compared with trends in neuroimaging, neuropathology, theory of mind and genetics ('four comparison areas'). The number of publications per 5-year block in all eight areas was calculated in order to identify significant changes in trends. Prior to 1986, only 12 publications were identified in the four major areas and 51 in the four comparison areas (42 for genetics). For each 5-year period, the total number of publications in the eight combined areas increased progressively. Most publications (552 of 895, 62%) in the four major areas were published in the last 5 years (2006-2010). Evaluation of

  20. Stochastic periodic solution of a non-autonomous toxic-producing phytoplankton allelopathy model with environmental fluctuation

    Science.gov (United States)

    Zhao, Yu; Yuan, Sanling; Zhang, Tonghua

    2017-03-01

    Phytoplankton allelopathy is an ecological phenomenon that concerns the interaction among toxic-producing phytoplankton. Recently, researchers pay great attention to whether the cyclic outbreaks of the harmful algal blooms are related with the allelopathy in a random fluctuating environment. In this paper, we are particularly interested in a non-autonomous toxic-producing phytoplankton allelopathy model with environmental fluctuation. For the model, we first consider the existence of the global positive solution and the boundary periodic solution. Then, by using Khasminskii's method and Lyapunov function, we derive the sufficient conditions for the existence of the nontrivial positive stochastically periodic solution. Our results show that the allelopathic effect plays an important role in the existence of the stochastic periodic solution, for example it can lead to the decrease of the peaks of the cyclic outbreaks of the harmful algal blooms. Numerical simulations are carried out to support our theoretical results.

  1. Exposure to Environmental Toxicants and Pathogenesis of Amyotrophic Lateral Sclerosis: State of the Art and Research Perspectives

    Directory of Open Access Journals (Sweden)

    Maria Rosaria Monsurrò

    2013-07-01

    Full Text Available There is a broad scientific consensus that amyotrophic lateral sclerosis (ALS, a fatal neuromuscular disease, is caused by gene-environment interactions. In fact, given that only about 10% of all ALS diagnosis has a genetic basis, gene-environmental interaction may give account for the remaining percentage of cases. However, relatively little attention has been paid to environmental and lifestyle factors that may trigger the cascade of motor neuron degeneration leading to ALS, although exposure to chemicals—including lead and pesticides—agricultural environments, smoking, intense physical activity, trauma and electromagnetic fields have been associated with an increased risk of ALS. This review provides an overview of our current knowledge of potential toxic etiologies of ALS with emphasis on the role of cyanobacteria, heavy metals and pesticides as potential risk factors for developing ALS. We will summarize the most recent evidence from epidemiological studies and experimental findings from animal and cellular models, revealing that potential causal links between environmental toxicants and ALS pathogenesis have not been fully ascertained, thus justifying the need for further research.

  2. Environmental Health Risks and Housing Values: Evidence from 1,600 Toxic Plant Openings and Closings†

    Science.gov (United States)

    Currie, Janet; Davis, Lucas; Greenstone, Michael

    2016-01-01

    Regulatory oversight of toxic emissions from industrial plants and understanding about these emissions’ impacts are in their infancy. Applying a research design based on the openings and closings of 1,600 industrial plants to rich data on housing markets and infant health, we find that: toxic air emissions affect air quality only within 1 mile of the plant; plant openings lead to 11 percent declines in housing values within 0.5 mile or a loss of about $4.25 million for these households; and a plant’s operation is associated with a roughly 3 percent increase in the probability of low birthweight within 1 mile. PMID:27134284

  3. Prostate cancer and toxicity from critical use exemptions of methyl bromide: Environmental protection helps protect against human health risks

    Directory of Open Access Journals (Sweden)

    Budnik Lygia T

    2012-01-01

    Full Text Available Abstract Background Although ozone-depleting methyl bromide was destined for phase-out by 2005, it is still widely applied as a consequence of various critical-use-exemptions and mandatory international regulations aiming to restrict the spread of pests and alien species (e.g. in globalized transport and storage. The withdrawal of methyl bromide because of its environmental risk could fortuitously help in the containment of its human toxicity. Methods We performed a systematic review of the literature, including in vitro toxicological and epidemiological studies of occupational and community exposure to the halogenated hydrocarbon pesticide methyl bromide. We focused on toxic (especially chronic or carcinogenic effects from the use of methyl bromide, on biomonitoring data and reference values. Eligible epidemiological studies were subjected to meta-analysis. Results Out of the 542 peer reviewed publications between 1990-2011, we found only 91 referring to toxicity of methyl bromide and 29 using the term "carcinogenic", "neoplastic" or "mutagenic". Several studies provide new additional data pertaining to the mechanistic aspects of methyl bromide toxicity. Few studies have performed a detailed exposure assessment including biomonitoring. Three evaluated epidemiological studies assessed a possible association between cancer and methyl bromide. Overall, exposure to methyl bromide is associated with an increased risk of prostate cancer OR, 1.21; 95% CI (0,98-1.49, P = 0.076. Two epidemiological studies have analyzed environmental, non-occupational exposure to methyl bromide providing evidence for its health risk to the general public. None of the epidemiological studies addressed its use as a fumigant in freight containers, although recent field and case reports do refer to its toxic effects associated with its use in shipping and storage. Conclusions Both the epidemiological evidence and toxicological data suggest a possible link between methyl

  4. An assessment of the environmental toxicity of hexavalent chromium in fish

    NARCIS (Netherlands)

    Putte, van der I.

    1981-01-01

    At present chromium is a common contaminant in surface waters in many countries. In water the metal may be present in the trivalent form (CrIII) or in the hexavalent form (CrVI), the latter of which is more toxic to aquatic organisms.The investigations presented in this thesis were aimed at a thorou

  5. Utilization of animal studies to determine the effects and human risks of environmental toxicants (drugs, chemicals, and physical agents).

    Science.gov (United States)

    Brent, Robert L

    2004-04-01

    deficiency is compounded by the fact that there are very few toxicology studies performed in children. That is why pregnant women and children are referred to as "therapeutic orphans." When animal studies are performed with newborn and developing animals, the results demonstrate that generalizations are less applicable and less predictable than the toxicology studies in pregnant animals. Although many studies reveal that the infant and the developing animal have difficulty in metabolizing drugs and are more vulnerable to the toxic effects of environmental chemicals, there are exceptions that indicate that infant and developing animals may be less vulnerable and more resilient to some drugs and chemicals. In other words, the generalization indicating that developing animals are always more sensitive to environmental toxicants is not valid. For animal toxicology studies to be useful, animal studies have to use modern concepts of pharmacokinetics and toxicokinetics, as well as method-of-action studies to determine whether animal data can be used for determining human risk. One example is the inability to determine carcinogenic risks in humans for some drugs and chemicals that produce tumors in rodents, because the oncogenesis is the result of peroxisome proliferation, a reaction that is of diminished importance in humans. Scientists can use animal studies to study the toxicokinetic and toxicodynamic aspects of environmental toxicants, but they have to be performed with the most modern techniques and interpreted with the highest level of scholarship and objectivity. Threshold exposures, maximum permissible exposures, and toxic effects can be estimated but have to be interpreted with caution when applying them to the human. Well-performed epidemiology studies are still the best method for determining the human risk and the effects of environmental toxicants.

  6. Impact of environmentally based chemical hardness on uranium speciation and toxicity in six aquatic species.

    Science.gov (United States)

    Goulet, Richard R; Thompson, Patsy A; Serben, Kerrie C; Eickhoff, Curtis V

    2015-03-01

    Treated effluent discharge from uranium (U) mines and mills elevates the concentrations of U, calcium (Ca), magnesium (Mg), and sulfate (SO4 (2-) ) above natural levels in receiving waters. Many investigations on the effect of hardness on U toxicity have been experiments on the combined effects of changes in hardness, pH, and alkalinity, which do not represent water chemistry downstream of U mines and mills. Therefore, more toxicity studies with water chemistry encountered downstream of U mines and mills are necessary to support predictive assessments of impacts of U discharge to the environment. Acute and chronic U toxicity laboratory bioassays were realized with 6 freshwater species in waters of low alkalinity, circumneutral pH, and a range of chemical hardness as found in field samples collected downstream of U mines and mills. In laboratory-tested waters, speciation calculations suggested that free uranyl ion concentrations remained constant despite increasing chemical hardness. When hardness increased while pH remained circumneutral and alkalinity low, U toxicity decreased only to Hyalella azteca and Pseudokirchneriella subcapitata. Also, Ca and Mg did not compete with U for the same uptake sites. The present study confirms that the majority of studies concluding that hardness affected U toxicity were in fact studies in which alkalinity and pH were the stronger influence. The results thus confirm that studies predicting impacts of U downstream of mines and mills should not consider chemical hardness. Environ Toxicol Chem 2015;34:562-574. © 2014 The Authors. Published by Wiley Periodicals, Inc. on behalf of SETAC.

  7. Chronic ZnO-NPs exposure at environmentally relevant concentrations results in metabolic and locomotive toxicities in Caenorhabditis elegans.

    Science.gov (United States)

    Huang, Chi-Wei; Li, Shang-Wei; Hsiu-Chuan Liao, Vivian

    2017-01-01

    ZnO nanoparticles (ZnO-NPs) are emerging contaminants that raise the concerns of potential risk in the aquatic environment. It has been estimated that the environmental ZnO-NPs concentration is 76 μg/l in the aquatic environment. Our aim was to determine the aquatic toxicity of ZnO-NPs with chronic exposure at environmentally relevant concentrations using the nematode Caenorhabditis elegans. Two simulated environmentally relevant mediums-moderately hard reconstituted water (EPA water) and simulated soil pore water (SSPW)-were used to represent surface water and pore water in sediment, respectively. The results showed that the ZnO-NPs in EPA water has a much smaller hydrodynamic diameter than that in SSPW. Although the ionic release of Zn ions increased time-dependently in both mediums, the Zn ions concentrations in EPA water increased two-fold more than that in SSPW at 48 h and 72 h. The ZnO-NPs did not induce growth defects or decrease head thrashes in C. elegans in either media. However, chronic exposure to ZnO-NPs caused a significant reduction in C. elegans body bends in EPA water even with a relatively low concentration (0.05 μg/l); similar results were not observed in SSPW. Moreover, at the same concentrations (50 and 500 μg/l), body bends in C. elegans were reduced more severely in ZnO-NPs than in ZnCl2 in EPA water. The ATP levels were consistently and significantly decreased, and ROS was induced after ZnO-NPs exposure (50 and 500 μg/l) in EPA water. Our results provide evidences that chronic exposure to ZnO-NPs under environmentally relevant concentrations causes metabolic and locomotive toxicities implicating the potential ecotoxicity of ZnO-NPs at low concentrations in aquatic environments.

  8. The incorporation of human toxicity criteria into Integrated Environmental Quality Standards. Discussion report supportive to the development of a harmonisation strategy

    NARCIS (Netherlands)

    Mennes W; Apeldoorn M van; Meijerinck M; Crommentuijn T; CSR

    1998-01-01

    The research described in this report aimes at the further development of integrated environmental standards which are to be designed to protect both humans and environmental species. Up to now only ecotoxicological data were incorporated in these standards. Techniques to incorporate human toxicity

  9. Children's vulnerability to toxic chemicals: a challenge and opportunity to strengthen health and environmental policy.

    Science.gov (United States)

    Landrigan, Philip J; Goldman, Lynn R

    2011-05-01

    A key policy breakthrough occurred nearly twenty years ago with the discovery that children are far more sensitive than adults to toxic chemicals in the environment. This finding led to the recognition that chemical exposures early in life are significant and preventable causes of disease in children and adults. We review this knowledge and recommend a new policy to regulate industrial and consumer chemicals that will protect the health of children and all Americans, prevent disease, and reduce health care costs. The linchpins of a new US chemical policy will be: first, a legally mandated requirement to test the toxicity of chemicals already in commerce, prioritizing chemicals in the widest use, and incorporating new assessment technologies; second, a tiered approach to premarket evaluation of new chemicals; and third, epidemiologic monitoring and focused health studies of exposed populations.

  10. UO(2) 2+ speciation determines uranium toxicity and bioaccumulation in an environmental Pseudomonas sp. isolate.

    Science.gov (United States)

    Vanengelen, Michael R; Field, Erin K; Gerlach, Robin; Lee, Brady D; Apel, William A; Peyton, Brent M

    2010-04-01

    In the present study, experiments were performed to investigate how representative cellulosic breakdown products, when serving as growth substrates under aerobic conditions, affect hexavalent uranyl cation (UO(2) (2+)) toxicity and bioaccumulation within a Pseudomonas sp. isolate (designated isolate A). Isolate A taken from the Cold Test Pit South (CTPS) region of the Idaho National Laboratory (INL), Idaho Falls, ID, USA. The INL houses low-level uranium-contaminated cellulosic material and understanding how this material, and specifically its breakdown products, affect U-bacterial interactions is important for understanding UO(2) (2+) fate and mobility. Toxicity was modeled using a generalized Monod expression. Butyrate, dextrose, ethanol, and lactate served as growth substrates. The potential contribution of bicarbonate species present in high concentrations was also investigated and compared with toxicity and bioaccumulation patterns seen in low-bicarbonate conditions. Isolate A was significantly more sensitive to UO(2) (2+) and accumulated significantly more UO(2) (2+) in low-bicarbonate concentrations. In addition, UO(2) (2+) growth inhibition and bioaccumulation varied depending on the growth substrate. In the presence of high bicarbonate concentrations, sensitivity to UO(2) (2+) inhibition was greatly mitigated, and did not vary between the four substrates tested. The extent of UO(2) (2+) accumulation was also diminished. The observed patterns were related to UO(2) (2+) aqueous complexation, as predicted by MINTEQ (ver. 2.52) (Easton, PA, USA). In the low- bicarbonate medium, the presence of positively charged and unstable UO(2) (2+)-hydroxide complexes explained both the greater sensitivity of isolate A to UO(2) (2+), and the ability of isolate A to accumulate significant amounts of UO(2) (2+). The exclusive presence of negatively charged and stable UO(2) (2+)-carbonate complexes in the high bi-carbonate medium explained the diminished sensitivity of

  11. Environmental Guidance Program reference book: Toxic substances control act. Revision 7

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-01

    This Reference Book contains a current copy of the Toxic Substances Control Act and those regulations that implement the statute and appear to be most relevant to DOE activities. The document is provided to DOE staff for informational purposes only and should not be interpreted as legal guidance. Questions concerning this Reference Book may be directed to Mark Petts, EH-231 (202/586-2609).

  12. Toxic Substances Control Act. Environmental Guidance Program Reference Book: Revision 6

    Energy Technology Data Exchange (ETDEWEB)

    1992-05-15

    This Reference Book contains a current copy of the Toxic Substances Control Act and those regulations that implement the statute and appear to be most relevant to DOE activities. The document is provided to DOE and contractor staff for informational purposes only and should not be interpreted as legal guidance. Questions concerning this Reference Book may be directed to Mark Petts, EH-231 (202/586-2609).

  13. Toxicity characterization of environmental chemicals by the US National Toxicology Program: an overview.

    Science.gov (United States)

    Chhabra, Rajendra S; Bucher, John R; Wolfe, Mary; Portier, Christopher

    2003-08-01

    The US National Toxicology Program (NTP) is an interagency program whose mission is to evaluate agents of public health concern by developing and applying the tools of modern toxicology and molecular biology. Chemicals substances or physical agents selected for toxicology and carcinogenesis evaluations by the NTP are usually studied in a series of subacute (14-day exposure), subchronic (90-day exposure) and chronic (2-year exposure) studies in rodents. The NTP has published more than 500 reports of the findings and conclusions from its toxicology and carcinogenesis studies. In more specialized studies, the NTP also evaluates adverse effects on the structure and function of the immune, reproductive, nervous, and respiratory systems. The program attempts to evaluate and appropriately incorporate new technologies to improve the way we study the toxicity of chemicals. For example, the program has extensively evaluated several transgenic mouse models for their potential use as short-term cancer screens and has been a full participant in an international effort to examine their usefulness in pharmaceutical registration. Toxicogenomics, an emerging scientific field that examines the expression of thousands of genes simultaneously in response to chemical exposure, holds promise for future application to better understand the underlying mechanisms of chemical toxicity. A number of public health issues being addressed by the NTP are not only of national importance but also have global impact, such as the potential for endocrine disruptors to influence development and carcinogenesis and the safety of herbal medicines and dietary supplements. The program participates in the preparation of national and international toxicity testing guidelines and the findings from NTP studies are widely used for risk assessments by international organizations and federal agencies. The NTP maintains databases that contain toxicity, and health and safety information on a large number of

  14. Acute toxicity and environmental risk of teflubenzuron to Daphnia magna, Poecilia reticulata and Lemna minor in the absence and presence of sediment.

    Science.gov (United States)

    Medeiros, Louise S; Souza, Jaqueline P; Winkaler, Elissandra U; Carraschi, Silvia P; Cruz, Claudinei; Souza-Júnior, Severino C; Machado-Neto, Joaquim G

    2013-01-01

    This study aimed to estimate the acute toxicity of teflubenzuron (1-(3,5-dichloro-2,4-difluorophenyl)-3-(2,6-difluorobenzoyl)urea) (TFB) for Daphnia magna, Lemna minor and Poecilia reticulata, in the absence and presence of sediment; evaluate the effect of sediment on the TFB bioavailability; and to classify this insecticide according to its environmental poisoning risk for agricultural and aquaculture uses. The tests of TFB acute toxicity were conducted in static system in a completely randomized design with increasing TFB concentrations, and a control group. The TFB has been classified according to the estimated values of EC50 and LC50 by its acute toxicity and environmental risk. The sediment significantly reduced toxicity and bioavailability of TFB in water column. Therefore, the insecticide can be classified as being highly toxic to Daphnia magna, which means the agricultural and aquacultural uses of TFB pose a high risk of environmental toxicity to non-target organisms. However, it was practically non-toxic to L. minor and P. reticulata.

  15. Acute environmental toxicity and persistence of methyl salicylate: A chemical agent simulant. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cataldo, D.A.; Ligotke, M.W.; Harvey, S.D.; Fellows, R.J.; Li, S.W.

    1994-06-01

    The interactions of methyl salicylate with plant foliage and soils were assessed using aerosol/vapor exposure methods. Measurements of deposition velocity and residence times for soils and foliar surfaces are reported. Severe plant contact toxicity was observed at foliar mass-loading levels above 4 {mu}g/cm{sup 2} leaf; however, recovery was noted after four to fourteen days. Methyl salicylate has a short-term effect on soil dehydrogenase activity, but not phosphatase activity. Results of the earthworm bioassay indicated only minimal effects on survival.

  16. Association of environmental toxic elements in biological samples of myocardial infarction patients at different stages.

    Science.gov (United States)

    Afridi, Hassan Imran; Kazi, Tasneem Gul; Kazi, Naveed; Kandhro, Ghulam Abbas; Baig, Jameel Ahmed; Jamali, Mohammad Khan; Arain, Mohammad Balal; Shah, Abdul Qadir; Shah, Faheem; Khan, Sumaira; Kolachi, Nida Fatima

    2011-06-01

    The exposure of toxic elements may directly or indirectly associate with different pathogenesis of heart diseases. In the present study, the association of arsenic (As), cadmium (Cd), cobalt (Co), lead (Pb), and nickel (Ni) in biological samples (whole blood and urine) and mortality from myocardial infarction (MI) patients at first, second, and third heart attacks was carried out. Both biological samples of 130 MI patients (77 male and 53 female), with ages ranging from 45 to 60 years, and 61 healthy persons (33 male and 28 female) of the same age group were collected. The elements in biological samples were assessed by electrothermal atomic absorption spectrophotometer, prior to microwave-assisted acid digestion. The validity of methodology was checked by the biological certified reference materials. During this study, 78% of 32 patients aged above 50 years, registered after third MI attack, died. In these subjects, the levels of As, Cd, Co, Ni, and Pb in blood samples were higher in MI patients as compared with referents (p < 0.05), while increased by 11.7%, 12.2%, 5.55%, and 7.2%, respectively, in the blood samples of those patients who tolerated the third MI attack (p = 0.12). The high level of understudied toxic elements may play a role in the mortality of MI patients.

  17. Inhalation Toxicology. V. Evaluation of Relative Toxicity to Rats of Thermal Decomposition Products from Two Aircraft Seat Fire-Blocking Materials.

    Science.gov (United States)

    1985-11-01

    only. The relative toxicity of the combustion gases was measured by determining time-to-incapacitation (ti) in the laboratory rat , the same endpoint... the laboratory rat was the measured response used to compare the relative toxicity of the combustion gases produced from the two materials. Because of

  18. [New biosensors for assessment of environmental toxicity based on marine luminescent bacteria].

    Science.gov (United States)

    Tsybul'skiĭ, I E; Sazykina, M A

    2010-01-01

    Sixteen strains of luminescent bacteria of Vibrio and Photobacterium genera were isolated from water of the Azov and Black seas. Two strains prospective for biotesting were genetically identified as Vibrio fisher Ve-9579 and Vibrio fisheri Ve-9580 according to Russian Industrial Microorganism Collection (VKMP) classification and accepted for depositing. The isolated luminescent strains exhibited high individual sensitivity to oil derived products, heavy metal salts, sodium dodecyl sulfate (SDS) and phenol (up to the maximum concentration limit for fishery impoundments). According to EC50, they are ten times more sensitive to heavy metal salts and potassium dichromate and 2-6 times more sensitive to SDSand phenol compared to P. phosphoreum (Cohn) Ford and Escherichia coli C600 (pPLS-5) strains. Using Vibrio fisheri VKMP Ve-9579 and Vibrio fisheri VKMP Ve-9580 as biosensors, we have shown their high sensitivity and efficacy to marine ecosystem toxicity assessment.

  19. Effect of environmental conditions on production of toxic shock syndrome toxin 1 by Staphylococcus aureus.

    Science.gov (United States)

    Wong, A C; Bergdoll, M S

    1990-01-01

    The kinetics of toxic shock syndrome toxin 1 (TSST-1) production by Staphylococcus aureus was studied in a fermentor in which aeration rate, atmospheric composition, pH, and temperature were controlled. The toxin was synthesized at a maximal rate during the exponential phase. High bacterial populations were not necessarily accompanied by high TSST-1 yields. Aerobiosis increased TSST-1 production, but excessive aeration had an adverse effect. Addition of CO2 enhanced TSST-1 yield by increasing toxin production rate and efficiency. Cultures with no pH control made more TSST-1 than those maintained at pH 5.5 to 7.5. Maximum TSST-1 yields were obtained when cultures were supplied with air (20 cm3/min) and CO2 (5 cm3/min) via a sintered glass sparger. PMID:2108084

  20. Whole Cell Biosensor Using Anabaena torulosa with Optical Transduction for Environmental Toxicity Evaluation

    Directory of Open Access Journals (Sweden)

    Ling Shing Wong

    2013-01-01

    Full Text Available A whole cell-based biosensor using Anabaena torulosa for the detection of heavy metals (Cu, Pb, and Cd, 2,4-dichlorophenoxyacetate (2,4-D, and chlorpyrifos was constructed. The cyanobacteria were entrapped on a cellulose membrane through filtration. Then, the membrane was dried and fixed into a cylindrical well, which was designed to be attached to an optical probe. The probe was connected to fluorescence spectrometer with optical fibre. The presence of the toxicants was indicated by the change of fluorescence emission, before and after the exposure. The linear detection ranges for Cu, Pb, and Cd were 2.5–10.0 µg/L, 0.5–5.0 µg/L, and 0.5–10.0 µg/L, respectively, while 2,4-D and chlorpyrifos shared similar linear ranges of 0.05–0.75 µg/L. The biosensor showed good sensitivity with the lowest limits of detection (LLD for Cu, Pb, Cd, 2,4-D and chlorpyrifos determined at 1.195 µg/L, 0.100 µg/L, 0.027 µg/L, 0.025 µg/L, and 0.025 µg/L, respectively. The overall reproducibility of the biosensor (n=3 was <±6.35%. The biosensor had been tested with different combinations of toxicants, with the results showing predominantly antagonistic responses. The results confirmed that the biosensor constructed in this report is suitable to be used in quantitative and qualitative detections of heavy metals and pesticides.

  1. Application of metallomic and metabolomic approaches in exposure experiments on laboratory mice for environmental metal toxicity assessment.

    Science.gov (United States)

    García-Sevillano, M A; García-Barrera, T; Gómez-Ariza, J L

    2014-02-01

    Metals have a central role in biological systems, regulating numerous cellular processes, and in other cases having toxic or deleterious effects on the metabolism. Hence, the study of metal-induced changes in cellular metabolic pathways is crucial to understanding the biological response associated with environmental issues. In this context, the finding of biomarkers has great interest, representing -omics techniques, such as metallomics and metabolomics, powerful tools for this purpose. The present work evaluates the exposure of mice Mus musculus to toxic metals (As, Cd and Hg), considering the changes induced in both the metallome and metabolome as a consequence of the high genetic homology between Mus musculus/Mus spretus mice, which allows the use of the database from M. musculus to identify the proteins and metabolites expressed by M. spretus. For this purpose a metallomic approach based on size exclusion chromatography (SEC) in combination with other complementary orthogonal separation techniques and heteroelement monitoring by ICP-ORS-qMS was performed, followed by identification of metallobiomolecules by organic mass spectrometry. In addition, simultaneous speciation of selenoproteins and selenometabolites in mouse plasma was accomplished by tandem (double) SEC-(dual) affinity chromatography (AF)-HPLC and online isotope dilution analysis (IDA)-ICP-ORS-qMS. Finally, the simultaneous changes in metabolic expression in mice caused by metal exposure (metabolome) were considered, using direct infusion mass spectrometry (DI-ESI-QqQ-TOF-MS) of extracts from mice plasma. Subsequently altered metabolites were identified using MS/MS experiments. The results obtained under controlled conditions were extrapolated to homologous free-living mice captured in Doñana National Park (DNP) and surroundings (southwest Spain) affected by As, Cd and Hg pollution. In summary, such studies are needed to understand the effect of heavy metal exposure and cope with heavy metal

  2. Environmental mutagenicity and toxicity caused by sodium metabisulfite in sea shrimp harvesting in Piauí, Brazil.

    Science.gov (United States)

    da Costa Machado Matos Carvalho, Ivana Mara; Cavalcante, Ana Amélia Melo; Dantas, Alisson Ferreira; Pereira, Danilo Leôncio Aguiar; Rocha, Francisco Cézar Costa; Oliveira, Francisco Massal de; Da Silva, Juliana

    2011-02-01

    Sodium metabisulfite is used in marine shrimp harvesting to prevent the occurrence of black spots. Shrimps are soaked in a sodium metabisulfite solution in ice, which is disposed of in sewages that run into marine canals, creating an environmental hazard. This study evaluates the toxicity and mutagenicity caused by sodium metabisulfite in sea waters and sediments collected in a shrimp farm in Cajueiro da Praia (Luis Correia), state of Piauí, Brazil, using the Allium cepa assay. Water and sediment samples were collected in the dry and in the rainy seasons, in three sites: upstream the shrimp farm (Site 1), at the point sodium metabisulfite is discharged (Site 2), and 100 m downstream the farm (Site 3). Three sample dilutions were used (50%, 25% and 10%) for all samples. A negative control (well water) and a positive control (copper sulfate 0.0006 mg mL⁻¹) were used in each experiment. At the end of the 72-h exposure period, onion roots were measured and removed. Mutagenicity analysis included the determination of mitotic index, chromosomal aberrations and the detection of micronuclei; analysis of root size and mitotic index were used as an index of toxicity. The A. cepa assay revealed that the water and sediments samples collected in the Piauí coast contaminated with sodium metabisulfite induce toxicity. The results demonstrate that the assay may be used as a regular tool in the analysis of water parameters in shrimp farms in the coast of Piauí state, and in strategies to preserve the region's marine ecosystem.

  3. Clinch River - Environmental Restoration Program (CR-ERP) Study, ambient water toxicity. Final report, October 21, 1993--October 28, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of October 21-28, 1993, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Due to serious reproduction/embryo abortion problems with the TVA daphnid cultures, TVA conducted tests during this study period using only fathead minnows. A split sample test using daphnids only will be scheduled during 1994 as a substitute for this study period. Surface water samples were collected by TVA Field Engineering personnel from Poplar Creek Mile 2.9, Mile 4.3, and Mile 5.1 on October 20, 22, and 25. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) in testing conducted by TVA.

  4. Anticedants and natural prevention of environmental toxicants induced accelerated aging of skin.

    Science.gov (United States)

    Tanuja Yadav; Mishra, Shivangi; Das, Shefali; Aggarwal, Shikha; Rani, Vibha

    2015-01-01

    Skin is frequently exposed to a variety of environmental and chemical agents that accelerate ageing. External stress such as UV radiations (UVR) and environmental pollutants majorly deteriorate the skin morphology, by activating certain intrinsic factors such as Reactive Oxygen Species (ROS) which trigger the activation of Matrix Metalloproteinases (MMPs) and inflammatory responses hence damaging the extracellular matrix (ECM) components. To counter this, an exogenous supply of anti-oxidants, is required since the endogenous anti-oxidant system cannot alone suffice the need. Bio-prospecting of natural resources for anti-oxidants has hence been intensified. Immense research is being carried out to identify potential plants with potent anti-oxidant activity against skin ageing. This review summarizes the major factors responsible for premature skin ageing and the plants being targeted to lessen the impact of those.

  5. The effect of environmental hypercapnia and size on nitrite toxicity in the striped catfish (Pangasianodon hypophthalmus)

    DEFF Research Database (Denmark)

    Hvas, Malthe; Damsgaard, Christian; Gam, Le Thi Hong

    2016-01-01

    Striped catfish (Pangasianodon hypophthalmus) are farmed intensively at high stocking densities in Vietnam where they are likely to encounter environmental hypercapnia as well as occasional high levels of aquatic nitrite. Nitrite competes with Cl- for uptake at the branchial HCO3-/Cl- exchanger...... in the initial phase of acid-base compensation. Overall, longer term environmental hypercapnia does not protect against nitrite uptake in P. hypophthalmus, but instead enhances it. In addition, we observed a significant size effect in nitrite accumulation, where large fish attained plasma [nitrite] above...... the ambient concentration, while small fish did not. Small P. hypophthalmus instead had significantly higher plasma [nitrate], and haemoglobin concentrations, revealing greater capacity for detoxifying nitrite by oxidising it to nitrate....

  6. Toxicity of endogenous and environmental estrogens: what is the role of elemental interactions?

    OpenAIRE

    Stancel, G M; Boettger-Tong, H L; Chiappetta, C; Hyder, S.M.; Kirkland, J L; Murthy, L; Loose-Mitchell, D S

    1995-01-01

    Many naturally occurring and man-made chemicals present in the environment possess estrogenic activity. Examples include plant and fungal products, pesticides, plasticizers, and other agricultural and industrial chemicals. These environmental estrogens as well as endogenous ovarian estrogens are thought to initiate their physiological actions in target tissues largely via interactions with a nuclear receptor system. The resultant estrogen-receptor complex in turn affects transcription via its...

  7. Hierarchical dose-response modeling for high-throughput toxicity screening of environmental chemicals.

    Science.gov (United States)

    Wilson, Ander; Reif, David M; Reich, Brian J

    2014-03-01

    High-throughput screening (HTS) of environmental chemicals is used to identify chemicals with high potential for adverse human health and environmental effects from among the thousands of untested chemicals. Predicting physiologically relevant activity with HTS data requires estimating the response of a large number of chemicals across a battery of screening assays based on sparse dose-response data for each chemical-assay combination. Many standard dose-response methods are inadequate because they treat each curve separately and under-perform when there are as few as 6-10 observations per curve. We propose a semiparametric Bayesian model that borrows strength across chemicals and assays. Our method directly parametrizes the efficacy and potency of the chemicals as well as the probability of response. We use the ToxCast data from the U.S. Environmental Protection Agency (EPA) as motivation. We demonstrate that our hierarchical method provides more accurate estimates of the probability of response, efficacy, and potency than separate curve estimation in a simulation study. We use our semiparametric method to compare the efficacy of chemicals in the ToxCast data to well-characterized reference chemicals on estrogen receptor α (ERα) and peroxisome proliferator-activated receptor γ (PPARγ) assays, then estimate the probability that other chemicals are active at lower concentrations than the reference chemicals.

  8. Toxic Volatile Organic Compounds in Environmental Tobacco Smoke:Emission Factors for Modeling Exposures of California Populations

    Energy Technology Data Exchange (ETDEWEB)

    Daisey, J.M.; Mahanama, K.R.R.; Hodgson, A.T.

    1994-10-01

    The primary objective of this study was to measure emission factors for selected toxic air in environmental tobacco smoke (ETS) using a room-sized environmental chamber. The emissions of 23 volatile organic compounds (VOCs), including 1,3-butadiene, three aldehydes and two vapor-phase N-nitrosarnines were determined for six commercial brands of cigarettes and reference cigarette 1R4F. The commercial brands were selected to represent 62.5% of the cigarettes smoked in California. For each brand, three cigarettes were machine smoked in the chamber. The experiments were conducted over four hours to investigate the effects of aging. Emission factors of the target compounds were also determined for sidestream smoke (SS). For almost all target compounds, the ETS emission factors were significantly higher than the corresponding SS values probably due to less favorable combustion conditions and wall losses in the SS apparatus. Where valid comparisons could be made, the ETS emission factors were generally in good agreement with the literature. Therefore, the ETS emission factors, rather than the SS values, are recommended for use in models to estimate population exposures from this source. The variabilities in the emission factors (pgkigarette) of the selected toxic air contaminants among brands, expressed as coefficients of variation, were 16 to 29%. Therefore, emissions among brands were generally similar. Differences among brands were related to the smoked lengths of the cigarettes and the masses of consumed tobacco. Mentholation and whether a cigarette was classified as light or regular did not significantly affect emissions. Aging was determined not to be a significant factor for the target compounds. There were, however, deposition losses of the less volatile compounds to chamber surfaces.

  9. Environmental and anthropogenic factors affecting the respiratory toxicity of volcanic ash in vitro

    Science.gov (United States)

    Tomašek, Ines; Horwell, Claire J.; Damby, David E.; Ayris, Paul M.; Barošová, Hana; Geers, Christoph; Petri-Fink, Alke; Rothen-Rutishauser, Barbara; Clift, Martin J. D.

    2016-04-01

    Human exposure to inhalable volcanic ash particles following an eruption is a health concern, as respirable-sized particles can potentially contribute towards adverse respiratory health effects, such as the onset or exacerbation of respiratory and cardiovascular diseases. Although there is substantial information on the mineralogical properties of volcanic ash that may influence its biological reactivity, knowledge as to how external factors, such as air pollution, contribute to and augment the potential reactivity is limited. To determine the respiratory effects of volcanic particle interactions with anthropogenic pollution and volcanic gases we will experimentally assess: (i) physicochemical characteristics of volcanic ash relevant to respiratory toxicity; (ii) the effects of simultaneously inhaling anthropogenic pollution (i.e. diesel exhaust particles (DEP)) and volcanic ash (of different origins); (iii) alteration of volcanic ash toxicity following interaction with volcanic gases. In order to gain a first understanding of the biological impact of the respirable fraction of volcanic ash when inhaled with DEP in vitro, we used a sophisticated 3D triple cell co-culture model of the human alveolar epithelial tissue barrier. The multi-cellular system was exposed to DEP [0.02 mg/mL] and then exposed to either a single or repeated dose of well-characterised respirable volcanic ash (0.26 ± 0.09 or 0.89 ± 0.29 μg/cm2, respectively) from the Soufrière Hills volcano, Montserrat for a period of 24 hours using a pseudo-air liquid interface approach. Cultures were subsequently assessed for adverse biological endpoints including cytotoxicity, oxidative stress and (pro)-inflammatory responses. Results indicated that the combination of DEP and respirable volcanic ash at sub-lethal concentrations incited a significant release of pro-inflammatory markers that was greater than the response for either DEP or volcanic ash, independently. Further work is planned, to determine if

  10. A docking-based receptor library of antibiotics and its novel application in predicting chronic mixture toxicity for environmental risk assessment.

    Science.gov (United States)

    Zou, Xiaoming; Zhou, Xianghong; Lin, Zhifen; Deng, Ziqing; Yin, Daqiang

    2013-06-01

    As organisms are typically exposed to chemical mixtures over long periods of time, chronic mixture toxicity is the best way to perform an environmental risk assessment (ERA). However, it is difficult to obtain the chronic mixture toxicity data due to the high expense and the complexity of the data acquisition method. Therefore, an approach was proposed in this study to predict chronic mixture toxicity. The acute (15 min exposure) and chronic (24 h exposure) toxicity of eight antibiotics and trimethoprim to Vibrio fischeri were determined in both single and binary mixtures. The results indicated that the risk quotients (RQs) of antibiotics should be based on the chronic mixture toxicity. To predict the chronic mixture toxicity, a docking-based receptor library of antibiotics and the receptor-library-based quantitative structure-activity relationship (QSAR) model were developed. Application of the developed QSAR model to the ERA of antibiotic mixtures demonstrated that there was a close affinity between RQs based on the observed chronic toxicity and the corresponding RQs based on the predicted data. The average coefficients of variations were 46.26 and 34.93 % and the determination coefficients (R (2)) were 0.999 and 0.998 for the low concentration group and the high concentration group, respectively. This result convinced us that the receptor library would be a promising tool for predicting the chronic mixture toxicity of antibiotics and that it can be further applied in ERA.

  11. The effect of environmental hypercapnia and size on nitrite toxicity in the striped catfish (Pangasianodon hypophthalmus).

    Science.gov (United States)

    Hvas, Malthe; Damsgaard, Christian; Gam, Le Thi Hong; Huong, Do Thi Thanh; Jensen, Frank B; Bayley, Mark

    2016-07-01

    Striped catfish (Pangasianodon hypophthalmus) are farmed intensively at high stocking densities in Vietnam where they are likely to encounter environmental hypercapnia as well as occasional high levels of aquatic nitrite. Nitrite competes with Cl(-) for uptake at the branchial HCO3(-)/Cl(-) exchanger, causing a drastic reduction in the blood oxygen carrying capacity through the formation of methaemoglobin and nitrosylhaemoglobin. Environmental hypercapnia induces a respiratory acidosis where the branchial HCO3(-)/Cl(-) exchange activity is reduced in order to retain HCO3(-) for pH recovery, which should lead to a reduced nitrite uptake. To assess the effect of hypercapnia on nitrite uptake, fish were cannulated in the dorsal aorta, allowing repeated blood sampling for measurements of haemoglobin derivatives, plasma ions and acid-base status during exposure to 0.9mM nitrite alone and in combination with acute and 48h acclimated hypercapnia over a period of 72h. Nitrite uptake was initially reduced during the hypercapnia-induced acidosis, but after pH recovery the situation was reversed, resulting in higher plasma nitrite concentrations and lower functional haemoglobin levels that eventually caused mortality. This suggests that branchial HCO3(-)/Cl(-) exchange activity is reduced only during the initial acid-base compensation, but subsequently increases with the greater availability of internal HCO3(-) counter-ions as pH is compensated. The data further suggest that branchial Na(+)/H(+) exchange plays a significant role in the initial phase of acid-base compensation. Overall, longer term environmental hypercapnia does not protect against nitrite uptake in P. hypophthalmus, but instead enhances it. In addition, we observed a significant size effect in nitrite accumulation, where large fish attained plasma [nitrite] above the ambient concentration, while small fish did not. Small P. hypophthalmus instead had significantly higher plasma [nitrate], and haemoglobin

  12. Epigenetic Mechanisms of Mouse Interstrain Variability in Genotoxicity of the Environmental Toxicant 1,3-Butadiene

    OpenAIRE

    2011-01-01

    1,3-Butadiene (BD) is a common environmental contaminant classified as “carcinogenic to humans.” Formation of BD-induced DNA adducts plays a major role in its carcinogenicity. BD is also an epigenotoxic agent (i.e., it affects DNA and histone methylation in the liver). We used a panel of genetically diverse inbred mice (NOD/LtJ, CAST/EiJ, A/J, WSB/EiJ, PWK/PhJ, C57BL/6J, and 129S1/SvImJ) to assess whether BD-induced genotoxic and epigenotoxic events may be subject to interstrain differences. ...

  13. Environmental technology applications: fact file on toxic contaminants in industrial waste process streams

    Energy Technology Data Exchange (ETDEWEB)

    Newkirk, H.W.

    1977-05-11

    This report is a compendium of facts related to chemical materials present in industrial waste process streams which have already been declared or are being evaluated as hazardous under the Toxic Substances Control Act. Since some 400 chemicals are presently covered by consensus standards, the substances reviewed are only those considered to be a major threat to public health and welfare by Federal and State regulatory agencies. For each hazardous material cited, the facts relate, where possible, to an identification of the stationary industrial sources, the kind of waste stream impacted, proposed regulations and established effluent standards, the volume of emissions produced each year, the volume of emissions per unit of industrial product produced, present clean-up capabilities, limitations, and costs. These data should be helpful in providing information for the assessment of potential problems, should be of use to the manufacturers of pollution control equipment or of chemicals for pollution control, should be of use to the operators or potential operators of processes which produce pollutants, and should help to define industry-wide emission practices and magnitudes.

  14. Occupational and environmental hazard assessments for the isolation, purification and toxicity testing of cyanobacterial toxins

    Directory of Open Access Journals (Sweden)

    Wickramasinghe Wasantha A

    2009-11-01

    Full Text Available Abstract Cyanobacteria can produce groups of structurally and functionally unrelated but highly potent toxins. Cyanotoxins are used in multiple research endeavours, either for direct investigation of their toxicologic properties, or as functional analogues for various biochemical and physiological processes. This paper presents occupational safety guidelines and recommendations for personnel working in field, laboratory or industrial settings to produce and use purified cyanotoxins and toxic cyanobacteria, from bulk harvesting of bloom material, mass culture of laboratory isolates, through routine extraction, isolation and purification. Oral, inhalational, dermal and parenteral routes are all potential occupational exposure pathways during the various stages of cyanotoxin production and application. Investigation of toxicologic or pharmacologic properties using in vivo models may present specific risks if radiolabelled cyanotoxins are employed, and the potential for occupational exposure via the dermal route is heightened with the use of organic solvents as vehicles. Inter- and intra-national transport of living cyanobacteria for research purposes risks establishing feral microalgal populations, so disinfection of culture equipment and destruction of cells by autoclaving, incineration and/or chlorination is recommended in order to prevent viable cyanobacteria from escaping research or production facilities.

  15. Review of endocrine disorders associated with environmental toxicants and possible involved mechanisms.

    Science.gov (United States)

    Maqbool, Faheem; Mostafalou, Sara; Bahadar, Haji; Abdollahi, Mohammad

    2016-01-15

    Endocrine disrupting chemicals (EDC) are released into environment from different sources. They are mainly used in packaging industries, pesticides and food constituents. Clinical evidence, experimental models, and epidemiological studies suggest that EDC have major risks for human by targeting different organs and systems in the body. Multiple mechanisms are involved in targeting the normal system, through estrogen receptors, nuclear receptors and steroidal receptors activation. In this review, different methods by which xenobiotics stimulate signaling pathways and genetic mutation or DNA methylation have been discussed. These methods help to understand the results of xenobiotic action on the endocrine system. Endocrine disturbances in the human body result in breast cancer, ovarian problems, thyroid eruptions, testicular carcinoma, Alzheimer disease, schizophrenia, nerve damage and obesity. EDC characterize a wide class of compounds such as organochlorinated pesticides, industrial wastes, plastics and plasticizers, fuels and numerous other elements that exist in the environment or are in high use during daily life. The interactions and mechanism of toxicity in relation to human general health problems, especially endocrine disturbances with particular reference to reproductive problems, diabetes, and breast, testicular and ovarian cancers should be deeply investigated. There should also be a focus on public awareness of these EDC risks and their use in routine life. Therefore, the aim of this review is to summarize all evidence regarding different physiological disruptions in the body and possible involved mechanisms, to prove the association between endocrine disruptions and human diseases.

  16. Occurrences of the toxic dinoflagellate Ostreopsis ovata in relation with environmental factors in Kerkennah Island (Southern coast of Tunisia)

    Institute of Scientific and Technical Information of China (English)

    Mounir Ben brahim; Morsi Feki; Abderahmene Bouain

    2015-01-01

    Objective: To study the seasonal and monthly variability of the toxic dinoflagellate Ostreopsis ovata (O. ovata) in relation to environmental parameters in Kerkennah Island. Methods: Three water samples replicate of one-litter were taken daily for ten consecutive days on 12 months. All sampling water was kept in the dark at ambient temperature until their microscopic observation. Environmental variables such as salinity and temperature were measured in the field concomitantly as phytoplankton sampling. Nutrients (ammonium, nitrite, nitrate, phosphate and silicate) were analysed in laboratory with Auto-analyser Luebbe type. Cell identification and enumeration in water samples were performed with an inverted microscope after the sedimentation. Results: The highest abundance of O. ovata was recorded in summer. Analysis of variance showed significant difference of abundance between seasons, whereas no significant difference for month was detected. Factorial analysis ordination showed a positive correlation of Ostreopsis mainly with temperature and low correlation with nitrite and nitrate whereas the second axis (with 26.30% of variance) showed that Ostreopsis was correlated with temperature and salinity. Conclusions: The maximum abundance of Ostreopsis was reached in summer when temperature was high and a low relationship between O. ovata and nutrient was detected.

  17. Introducing Environmental Toxicology in Instructional Labs: The Use of a Modified Amphibian Developmental Toxicity Assay to Support Inquiry-Based Student Projects

    Science.gov (United States)

    Sauterer, Roger; Rayburn, James R.

    2012-01-01

    Introducing students to the process of scientific inquiry is a major goal of high school and college labs. Environmental toxins are of great concern and public interest. Modifications of a vertebrate developmental toxicity assay using the frog Xenopus laevis can support student-initiated toxicology experiments that are relevant to humans. Teams of…

  18. Temporal assessment of copper speciation, bioavailability and toxicity in UK freshwaters using chemical equilibrium and biotic ligand models: Implications for compliance with copper environmental quality standards.

    Science.gov (United States)

    Lathouri, Maria; Korre, Anna

    2015-12-15

    Although significant progress has been made in understanding how environmental factors modify the speciation, bioavailability and toxicity of metals such as copper in aquatic environments, the current methods used to establish water quality standards do not necessarily consider the different geological and geochemical characteristics of a given site and the factors that affect copper fate, bioavailability potential and toxicity. In addition, the temporal variation in the concentration and bioavailable metal fraction is also important in freshwater systems. The work presented in this paper illustrates the temporal and seasonal variability of a range of water quality parameters, and Cu speciation, bioavailability and toxicity at four freshwaters sites in the UK. Rivers Coquet, Cree, Lower Clyde and Eden (Kent) were selected to cover a broad range of different geochemical environments and site characteristics. The monitoring data used covered a period of around six years at almost monthly intervals. Chemical equilibrium modelling was used to study temporal variations in Cu speciation and was combined with acute toxicity modelling to assess Cu bioavailability for two aquatic species, Daphnia magna and Daphnia pulex. The estimated copper bioavailability, toxicity levels and the corresponding ecosystem risks were analysed in relation to key water quality parameters (alkalinity, pH and DOC). Although copper concentrations did not vary much during the sampling period or between the seasons at the different sites; copper bioavailability varied markedly. In addition, through the chronic-Cu BLM-based on the voluntary risk assessment approach, the potential environmental risk in terms of the chronic toxicity was assessed. A much higher likelihood of toxicity effects was found during the cold period at all sites. It is suggested that besides the metal (copper) concentration in the surface water environment, the variability and seasonality of other important water quality

  19. Computational prediction of microRNA networks incorporating environmental toxicity and disease etiology

    Science.gov (United States)

    Li, Jie; Wu, Zengrui; Cheng, Feixiong; Li, Weihua; Liu, Guixia; Tang, Yun

    2014-07-01

    MicroRNAs (miRNAs) play important roles in multiple biological processes and have attracted much scientific attention recently. Their expression can be altered by environmental factors (EFs), which are associated with many diseases. Identification of the phenotype-genotype relationships among miRNAs, EFs, and diseases at the network level will help us to better understand toxicology mechanisms and disease etiologies. In this study, we developed a computational systems toxicology framework to predict new associations among EFs, miRNAs and diseases by integrating EF structure similarity and disease phenotypic similarity. Specifically, three comprehensive bipartite networks: EF-miRNA, EF-disease and miRNA-disease associations, were constructed to build predictive models. The areas under the receiver operating characteristic curves using 10-fold cross validation ranged from 0.686 to 0.910. Furthermore, we successfully inferred novel EF-miRNA-disease networks in two case studies for breast cancer and cigarette smoke. Collectively, our methods provide a reliable and useful tool for the study of chemical risk assessment and disease etiology involving miRNAs.

  20. Gene expression profiling to identify the toxicities and potentially relevant human disease outcomes associated with environmental heavy metal exposure.

    Science.gov (United States)

    Korashy, Hesham M; Attafi, Ibraheem M; Famulski, Konrad S; Bakheet, Saleh A; Hafez, Mohammed M; Alsaad, Abdulaziz M S; Al-Ghadeer, Abdul Rahman M

    2017-02-01

    Heavy metals are the most commonly encountered toxic substances that increase susceptibility to various diseases after prolonged exposure. We have previously shown that healthy volunteers living near a mining area had significant contamination with heavy metals associated with significant changes in the expression of some detoxifying genes, xenobiotic metabolizing enzymes, and DNA repair genes. However, alterations of most of the molecular target genes associated with diseases are still unknown. Thus, the aims of this study were to (a) evaluate the gene expression profile and (b) identify the toxicities and potentially relevant human disease outcomes associated with long-term human exposure to environmental heavy metals in mining area using microarray analysis. For this purpose, 40 healthy male volunteers who were residents of a heavy metal-polluted area (Mahd Al-Dhahab city, Saudi Arabia) and 20 healthy male volunteers who were residents of a non-heavy metal-polluted area were included in the study. Total RNA was isolated from whole blood using PAXgene Blood RNA tubes and then reversed transcribed and hybridized to the gene array using the Affymetrix U219 GeneChip. Microarray analysis showed about 2129 genes were identified and differentially altered, among which a shared set of 425 genes was differentially expressed in the heavy metal-exposed groups. Ingenuity pathway analysis revealed that the most altered gene-regulated diseases in heavy metal-exposed groups included hematological and developmental disorders and mostly renal and urological diseases. Quantitative real-time polymerase chain reaction closely matched the microarray data for some genes tested. Importantly, changes in gene-related diseases were attributed to alterations in the genes encoded for protein synthesis. Renal and urological diseases were the diseases that were most frequently associated with the heavy metal-exposed group. Therefore, there is a need for further studies to validate these

  1. Switching slips. Building blocks for a robust environmental policy for the 21st century; Wissels omzetten. Bouwstenen voor een robuust milieubeleid voor de 21e eeuw

    Energy Technology Data Exchange (ETDEWEB)

    Hoogervorst, N.; Hajer, M.; Dietz, F.; Timmerhuis, J.; Kruitwagen, S.

    2013-06-15

    With this 'signal report', PBL (Netherlands Environmental Assessment Agency) offers building blocks for a robust environmental policy for the twentyfirst century, such as changes in consumer behavior, new coalitions of interests and stakeholders, and the establishment of an investment fund for eco-innovation. Which track does the Netherlands want to follow? With this essay, PBL is calling for a broad public debate on this issue [Dutch] In dit signalenrapport reikt het PBL (Planbureau voor de Leefomgeving) bouwstenen aan voor een robuust milieubeleid voor de eenentwintigste eeuw, zoals gedragsverandering van consumenten, nieuwe coalities van belangen en betrokkenen, en de oprichting van een investeringsfonds voor eco-innovatie. Welk spoor wil Nederland bewandelen? Met dit essay roept het PBL op tot een breed maatschappelijk debat over deze vraag.

  2. Hawaii Census 2000 Blocks

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer represents Census 2000 demographic data derived from the PL94-171 redistricting files and SF3. Census geographic entities include blocks, blockgroups...

  3. Zebrafish transgenic line huORFZ is an effective living bioindicator for detecting environmental toxicants.

    Directory of Open Access Journals (Sweden)

    Hung-Chieh Lee

    Full Text Available Reliable animal models are invaluable for monitoring the extent of pollution in the aquatic environment. In this study, we demonstrated the potential of huORFZ, a novel transgenic zebrafish line that harbors a human upstream open reading frame of the chop gene fused with GFP reporter, as an animal model for monitoring environmental pollutants and stress-related cellular processes. When huORFZ embryos were kept under normal condition, no leaked GFP signal could be detected. When treated with hazardous chemicals, including heavy metals and endocrine-disrupting chemicals near their sublethal concentrations (LC50, huORFZ embryos exhibited different tissue-specific GFP expression patterns. For further analysis, copper (Cu2+, cadmium (Cd2+ and Chlorpyrifos were applied. Cu2+ triggered GFP responses in skin and muscle, whereas Cd2+ treatment triggered GFP responses in skin, olfactory epithelium and pronephric ducts. Moreover, fluorescence intensity, as exhibited by huORFZ embryos, was dose-dependent. After surviving treated embryos were returned to normal condition, survival rates, as well as TUNEL signals, returned to pretreatment levels with no significant morphological defects observed. Such results indicated the reversibility of treatment conditions used in this study, as long as embryos survived such conditions. Notably, GFP signals decreased along with recovery, suggesting that GFP signaling of huORFZ embryos likely reflected the overall physiological condition of the individual. To examine the performance of the huORFZ line under real-world conditions, we placed huORFZ embryos in different river water samples. We found that the huORFZ embryos correctly detected the presence of various kinds of pollutants. Based on these findings, we concluded that such uORFchop-based system can be integrated into a first-line water alarm system monitoring the discharge of hazardous pollutants.

  4. Environmental toxicity of effluents of different laboratories of a compounding pharmacy

    Directory of Open Access Journals (Sweden)

    Luciano Henrique Pinto

    2016-11-01

    Full Text Available There is a growing concern over so-called "emerging pollutants" in the production of pharmaceuticals. These pollutants reach the environment from household waste or from leftovers generated during production. In small concentrations of the order of micrograms per liter or less, or in concentrations ineffective at producing a biological response in humans in the short-term, chronic exposure can still have a great impact on the environment. This study evaluated the possible risk of contamination posed by the release of raw materials from small-scale drug production by compounding pharmacies, based on an ecotoxicity assessment conducted by biomonitoring Euglena gracilis algae. The study also investigated the impacts on behavior and the changes in the photosynthesis process of this algae. Samples of four laboratories with different demands were comparatively analyzed. Behavioral changes of the algae (ascent rate to the surface, r-value and speed of movement were assessed by biomonitoring NG-TOX and photosynthetic parameters were measured by pulse-amplitude modulation fluorometer (PAM. The results showed that the effluent from hormone laboratory that had a low semestral production had little impact. On another hand, the effluent from the psychotropics laboratory, even with intermediate demand, had a significant impact on the behavior and photosynthetic activity of algae. The behavior differences observed between the different sectors of drugs shows that the impacts and potential environmental risks are different for each sector. The demand and the different substances manipulated can be crucial in risk classification and in the choice of decontamination methods.

  5. Rock blocks

    OpenAIRE

    Turner, W.

    2007-01-01

    Consider representation theory associated to symmetric groups, or to Hecke algebras in type A, or to q-Schur algebras, or to finite general linear groups in non-describing characteristic. Rock blocks are certain combinatorially defined blocks appearing in such a representation theory, first observed by R. Rouquier. Rock blocks are much more symmetric than general blocks, and every block is derived equivalent to a Rock block. Motivated by a theorem of J. Chuang and R. Kessar in the case of sym...

  6. Exposure information in environmental health research: Current opportunities and future directions for particulate matter, ozone, and toxic air pollutants

    Energy Technology Data Exchange (ETDEWEB)

    McKone, Thomas E.; Ryan, P. Barry; Ozkaynak, Haluk

    2007-02-01

    Understanding and quantifying outdoor and indoor sources of human exposure are essential but often not adequately addressed in health-effects studies for air pollution. Air pollution epidemiology, risk assessment, health tracking and accountability assessments are examples of health-effects studies that require but often lack adequate exposure information. Recent advances in exposure modeling along with better information on time-activity and exposure factors data provide us with unique opportunities to improve the assignment of exposures for both future and ongoing studies linking air pollution to health impacts. In September 2006, scientists from the US Environmental Protection Agency (EPA) and the Centers for Disease Control and Prevention (CDC) along with scientists from the academic community and state health departments convened a symposium on air pollution exposure and health in order to identify, evaluate, and improve current approaches for linking air pollution exposures to disease. This manuscript presents the key issues, challenges and recommendations identified by the exposure working group, who used cases studies of particulate matter, ozone, and toxic air pollutant exposure to evaluate health-effects for air pollution. One of the over-arching lessons of this workshop is that obtaining better exposure information for these different health-effects studies requires both goal-setting for what is needed and mapping out the transition pathway from current capabilities to meeting these goals. Meeting our long-term goals requires definition of incremental steps that provide useful information for the interim and move us toward our long-term goals. Another over-arching theme among the three different pollutants and the different health study approaches is the need for integration among alternate exposure assessment approaches. For example, different groups may advocate exposure indicators, biomonitoring, mapping methods (GIS), modeling, environmental media

  7. Interactive effects of pesticide mixtures, predators, and environmental regimes on the toxicity of two pesticides to red-eyed tree frog larvae.

    Science.gov (United States)

    Johnson, Laura A; Welch, Bill; Whitfield, Steven M

    2013-10-01

    Global amphibian declines have many corroborative causes, and the use of pesticides in agriculture is a likely contributor. In places with high pesticide usage, such as Costa Rica, agrochemical pesticides may interact with other factors to contribute to rapid species losses. Classical ecotoxicological studies rarely address the effects of a pesticide in combination with other stressors. The present study investigated the synergistic roles of 2 pesticides (chlorothalonil and endosulfan), predator stress, and environmental regimes (controlled laboratory environments versus ambient conditions) on the survival of red-eyed tree frog larvae (Agalychnis callidryas). No synergistic effects of pesticide mixtures or predator stress were found on the toxicity of either chlorothalonil or endosulfan. Both pesticides, however, were considerably more toxic under realistic ambient temperature regimes than in a climate-controlled laboratory. Overall, endosulfan displayed the highest toxicity to tadpoles, although chlorothalonil was also highly toxic. The median lethal concentration estimated to kill 50% of a tested population (LC50) for endosulfan treatments under ambient temperatures was less than one-half of that for laboratory treatments (3.26 µg/L and 8.39 µg/L, respectively). Studies commonly performed in stable temperature-controlled laboratories may significantly underestimate toxicity compared with more realistic environmental regimes. Furthermore, global climatic changes are leading to warmer and more variable climates and may increase impacts of pesticides on amphibians.

  8. Static renewal tests using Pimephales promelas (fathead minnows) and Ceriodaphnia dubia (daphnids). Clinch River-Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Russell, C.L.

    1993-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of July 22--29, 1993. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field engineering personnel from Clinch River Mile 19.0 and Mile 22.0 on July 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; and Reference toxicant test information.

  9. Static renewal tests using Pimephales promelas (fathead minnows) and Ceriodaphnia dubia (daphnids). Clinch River-Environmental Restoration Program (CR-ERP) pilot study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1993-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a pilot study during the week of April 22--29, 1993, prior to initiation of CR-ERP Phase 2 Sampling and Analysis activities. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 9.0 and Poplar Creek Kilometer 1.6 on April 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; Reference toxicant test information; and Personnel training documentation.

  10. Static renewal tests using Pimephales promelas (fathead minnows). Clinch River-Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1993-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of October 21--28, 1993. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Due to serious reproduction/embryo abortion problems with the TVA daphnid cultures, TVA conducted tests during this study period using only fathead minnows. Surface water samples were collected by TVA Field Engineering personnel from Poplar Creek Mile 2.9, Mile 4.3, and Mile 5.1 on October 20, 22, and 25. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; and Reference toxicant test information.

  11. Scenario-targeted toxicity assessment through multiple endpoint bioassays in a soil posing unacceptable environmental risk according to regulatory screening values.

    Science.gov (United States)

    Rodriguez-Ruiz, A; Etxebarria, J; Boatti, L; Marigómez, I

    2015-09-01

    Lanestosa is a chronically polluted site (derelict mine) where the soil (Lanestosa (LA) soil) exceeds screening values (SVs) of regulatory policies in force (Basque Country; Europe) for Zn, Pb and Cd. A scenario-targeted toxicity assessment was carried out on the basis of a multi-endpoint bioassay approach. Acute and chronic toxicity bioassays were conducted with selected test species (Vibrio fischeri, Dictyostelium discoideum, Lactuca sativa, Raphanus sativus and Eisenia fetida) in combination with chemical analysis of soils and elutriates and with bioaccumulation studies in earthworms. Besides, the toxicity profile was compared with that of the mine runoff (RO) soil and of a fresh artificially polluted soil (LAAPS) resembling LA soil pollutant profile. Extractability studies in LA soil revealed that Pb, Zn and Cd were highly available for exchange and/or release into the environment. Indeed, Pb and Zn were accumulated in earthworms and LA soil resulted to be toxic. Soil respiration, V. fischeri, vegetative and developmental cycles of D. discoideum and survival and juvenile production of E. fetida were severely affected. These results confirmed that LA soil had unacceptable environmental risk and demanded intervention. In contrast, although Pb and Zn concentrations in RO soil revealed also unacceptable risk, both metal extractability and toxicity were much lower than in LA soil. Thus, within the polluted site, the need for intervention varied between areas that posed dissimilar risk. Besides, since LAAPS, with a high exchangeable metal fraction, was the most toxic, ageing under in situ natural conditions seemingly contributed to attenuate LA soil risk. As a whole, combining multi-endpoint bioassays with scenario-targeted analysis (including leaching and ageing) provides reliable risk assessment in soils posing unacceptable environmental risk according to SVs, which is useful to optimise the required intervention measures.

  12. Characterization of basic immune function parameters in the fathead minnow (Pimephales promelas), a common model in environmental toxicity testing.

    Science.gov (United States)

    Thornton, Leah M; LeSueur, Meriel C; Yost, Alexandra T; Stephens, Dane A; Oris, James T; Sellin Jeffries, Marlo K

    2017-02-01

    The fathead minnow (Pimephales promelas) is an environmental sentinel species, commonly used in toxicity testing. However, there is a lack of data regarding basic immune function in this species. To improve the usefulness of the fathead minnow as a model for basic immune function and immunotoxicity, this study sought to 1) compare the differential expression of immune function genes in naïve fathead minnows and 2) determine the effects of pathogen exposure on immune gene expression and spleen index. To accomplish this, kidney, spleen and liver tissue were collected three days post injection (dpi) from adult male fathead minnows from each of the following groups: 1) uninjected control 2) sham-injected (Hank's balanced salt solution) and 3) pathogen-injected (Yersinia ruckeri). Spleen tissue was also collected at seven and 14 dpi. Differential tissue expression of immune function genes was evaluated in naïve minnows and expression patterns were similar to those found in other fish species, with liver tissue generally having the highest amount of expression. Following pathogen injection, the expression of complement component 3 (c3) (4.4-fold, kidney; 2.5-fold, liver), interleukin 11 (il11) (4.8-fold, kidney; 15.2-fold, liver) and interleukin 1β (il1β) (8.2-fold, kidney; 17.2-fold, spleen; 2.6-fold, liver) were significantly upregulated. Elastase 2 (elas2) was significantly downregulated (5.8-fold) in liver tissue. A significant increase in spleen index at seven dpi was also observed in pathogen-injected minnows. This study has identified endpoints that are part of the normal response to pathogen in fathead minnows, an essential step toward the development of the fathead minnow as a model for immunotoxicity evaluations.

  13. Ecological impacts of environmental toxicants and radiation on the microbial ecosystem: a model simulation of computational microbiology

    Energy Technology Data Exchange (ETDEWEB)

    Doi, Masahiro; Sakashita, Tetsuya; Ishii, Nobuyoshi; Fuma, Shoichi; Takeda, Hiroshi; Miyamoto, Kiriko; Yanagisawa, K.; Nakamura, Yuji [National Institute of Radiological Sciences, Inage, Chiba (Japan); Kawabata, Zenichiro [Center for Ecological Research, Kyoto Univ., Otsu, Shiga (Japan)

    2000-05-01

    stochasticities according to time since inoculation, and their population showed a non-linear dynamics. When SIM-COSM is stressed by environmental toxicants and radiation, it shows systematic adaptive response to a certain level. When the impacts exceeded the tolerable level, extinction risk of the ecosystem was significant. More computer-based simulation trials are left open as our future assignment. (author)

  14. Static renewal tests using Pimephales promelas (fathead minnows) and Ceriodaphnia dubia (daphnids). Clinch River-Environmental Restoration Program (CR-ERP) study, ambient water toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1994-12-31

    Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of January 25--February 1, 1994. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected from Clinch River Mile 9.0, Poplar Creek Mile 1.0, and Poplar Creek Mile 2.9 on January 24, 26, and 28. Samples were partitioned and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) to fathead minnows; however, toxicity to daphnids was demonstrated in undiluted samples from Poplar Creek Mile 1.0 in testing conducted by TVA based on hypothesis testing of data. Point estimation (IC{sub 25}) analysis of the data, however, showed no toxicity in PCM 1.0 samples. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; Meter calibrations; and Reference toxicant test information.

  15. Environmental pollution control through geo - botanical means - a case study of Manikpur block, Korba coalfield, M.P., India

    Energy Technology Data Exchange (ETDEWEB)

    Sikarwar, S.S.; Guha, S.; Singh, K.N. [Vikram Univ., Ujjain (India). School of Studies in Geology

    1999-09-01

    In the present paper, an environmental analysis of Manikpur area, Korba coalfield, Bilaspur, M.P., India is undertaken. The area lies in the Geological Survey of India Toposheet no. 64J/11 Latitude 82 42'54''-82 45'10'' North; Longitude 22 18'46''-22 19'46'' East. The paper deals with pollution and its control measures through the natural plants found in the vicinity of the coalmines, namely Mangifera indica, Eucalyptus spp., Cassia siamea, Delbergia sissoo, etc. The plants control the Suspended Particulate Matter (SPM), Nitrous Oxides (NOx), Sulphur Oxides (SOx) of the mines and mining site. Therefore, plantation in the mining site should be encouraged. (orig.)

  16. Population Blocks.

    Science.gov (United States)

    Smith, Martin H.

    1992-01-01

    Describes an educational game called "Population Blocks" that is designed to illustrate the concept of exponential growth of the human population and some potential effects of overpopulation. The game material consists of wooden blocks; 18 blocks are painted green (representing land), 7 are painted blue (representing water); and the remaining…

  17. Role of certain environmental factors on cadmium uptake and toxicity in Spirodela polyrhiza (L.) Schleid. and Azolla pinnata R. Br.

    Science.gov (United States)

    Gaur, J P; Noraho, N

    1995-09-01

    Effects of pH, temperature, EDTA and photosynthetically available radiation on the uptake and toxicity of Cd was investigated in Spirodela polyrhiza (L.) Schleid. and Azolla pinnata R. Br. In general, Cd toxicity was accentuated in conditions which favoured enhanced intracellular Cd uptake. Extracellular binding and intracellular uptake of Cd were lowered at pH values > 7 due to reduced availability of the aquo ion; consequently, toxicity was markedly reduced. At pH value 99%) remains available as the aquo ion. The presence of EDTA in the medium decreased extracellular binding, intracellular uptake and toxicity of Cd in test plants. This was due to formation of Cd-EDTA complex which was obviously not available to test plants. Elevation of temperature increased intracellular Cd uptake and this resulted in enhanced toxic effects. Similarly, increase in photosynthetically available radiation caused a slight increase in Cd uptake and toxicity in test plants. Obviously, rise in temperature or PAR increased metabolic activities of test plants thereby leading to increased Cd transport and toxicity.

  18. Toxics Release Inventory (TRI)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Toxics Release Inventory (TRI) is a dataset compiled by the U.S. Environmental Protection Agency (EPA). It contains information on the release and waste...

  19. Superalloy Lattice Block Structures

    Science.gov (United States)

    Nathal, M. V.; Whittenberger, J. D.; Hebsur, M. G.; Kantzos, P. T.; Krause, D. L.

    2004-01-01

    Initial investigations of investment cast superalloy lattice block suggest that this technology will yield a low cost approach to utilize the high temperature strength and environmental resistance of superalloys in lightweight, damage tolerant structural configurations. Work to date has demonstrated that relatively large superalloy lattice block panels can be successfully investment cast from both IN-718 and Mar-M247. These castings exhibited mechanical properties consistent with the strength of the same superalloys measured from more conventional castings. The lattice block structure also accommodates significant deformation without failure, and is defect tolerant in fatigue. The potential of lattice block structures opens new opportunities for the use of superalloys in future generations of aircraft applications that demand strength and environmental resistance at elevated temperatures along with low weight.

  20. Environmental benignity of a pesticide in soft colloidal hydrodispersive nanometric form with improved toxic precision towards the target organisms than non-target organisms.

    Science.gov (United States)

    Balaji, A P B; Sastry, Thotapalli P; Manigandan, Subramani; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2017-02-01

    Mosquito-borne diseases are of major concern as they cause devastating health effects, morbidity, and mortality in the human population. Conventional pesticides have failed to curb the mosquito population due to the development of insensitivity in mosquitoes. Hence, higher dosages of pesticides along with their toxic solubilizers have been employed, which have led to raise in pesticide pollution load, environmental toxicity, and human health concerns. As a realisation for the requirement of alternative pesticides, the present study has involved in the formulation of a hydrodispersive nanometric colloidal form of deltamethrin (NDM), a type-II pyrethroid pesticide, from its hydroimmisicible parental form (PDM). The mean hydrodynamic diameter of the droplets was found to be 30.6±4.6nm by dynamic light scattering study (DLS). High-resolution transmission electron micrographs have revealed the spherical structure of the droplets with a size range of 35-40nm. The NDM was found to possess sedimentation resistance, intrinsic and hydrodispersive stability. The toxicity of NDM and PDM was comparatively investigated on target organisms (Culex tritaeniorhynchus and Culex quinquefasciatus mosquitoes) and non-target organisms (Allium cepa - Bioindicator of toxicants and Rhizobium sp. - Soil bacteria). As comparative to PDM, NDM has exerted higher efficacy on adult mosquito and larval population, even at low-level concentrations. However, in the case of non-target organisms, the NDM toxicity was lower than PDM. Comprehensively, the study has concluded the potential advantage of formulating conventional pesticides into nanometric soft colloidal form for the improved toxic precision on target organisms (mosquitoes). This ensures the ability of NDM to combat against the mosquito population even at lower concentrations, thereby reducing the pesticide exposure load towards the environment and human population.

  1. Response of phytochelatins and their relationship with cadmium toxicity in a floating macrophyte Pistia stratiotes L. at environmentally relevant concentrations.

    Science.gov (United States)

    Wang, C; Wang, L Y; Sun, Q

    2010-02-01

    An indoor experiment was undertaken to investigate the response of phytochelatins and their relationship to cadmium toxicity in Pistia stratiotes L., a free-floating macrophyte, exposed to low concentrations of cadmium typically found in realistic environments. Cadmium concentrations of 0.01 to 0.08 microM had no toxic effects on the growth of this plant, as indicated by no significant changes in the fresh weights of leaves and roots and the slight induction of phytochelatins in plant tissues, whereas cadmium concentrations of 0.16 to 1 microM were toxic, and cadmium toxicity increased with the increase of cadmium concentrations in solutions, accompanied by the dramatic production of phytochelatins in plant tissues, especially in roots. There was a positive correction between root phytochelatin levels and cadmium toxicity, as measured by the growth inhibition rate of the root fresh weight. The results suggested that phytochelatins in aquatic macrophytes can serve as sensitive biomarkers for heavy metal toxicity in a moderately polluted water environment.

  2. Marine Toxic Substance and other data from bottle casts from NOAA Ship DISCOVERER as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1976-09-08 to 1976-09-24 (NODC Accession 7700044)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine Toxic Substance and other data were collected from bottle casts from NOAA Ship DISCOVERER. Data were collected by Pacific Marine Environmental Laboratory...

  3. Marine toxic substance and other data from the Gulf of Alaska from the MOANA WAVE as part of the Outer Continental Shelf Environmental Assessment Program from 25 June 1976 to 078 July 1976 (NODC Accession 7601849)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected in the Gulf of Alaska from the MOANA WAVE. Data were collected by Pacific Marine Environmental Laboratory (PMEL)...

  4. Toxic substance and pollutant data from bottle casts from NOAA Ship DISCOVERER as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1975-09-16 to 1975-11-01 (NODC Accession 7600631)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Toxic substance and pollutant data were collected from bottle casts from NOAA Ship DISCOVERER. Data were collected by Pacific Marine Environmental Laboratory (PMEL)...

  5. Marine Toxic Substance and other data from bottle casts in the Gulf of Alaska from the ACONA as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 28 June 1977 to 16 July 1977 (NODC Accession 7700756)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine Toxic Substance and other data were collected from bottle casts in the Gulf of Alaska from the ACONA. Data were collected by Pacific Marine Environmental...

  6. Marine Toxic Substance and other data from bottle casts in the Gulf of Alaska from the ACONA as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 02 July 1977 to 11 July 1977 (NODC Accession 7800451)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine Toxic Substance and other data were collected from bottle casts in the lower Cook Inlet from the ACONA. Data were collected by Pacific Marine Environmental...

  7. Marine Toxic Substance and other data from bottle casts in the Bering Sea from helicopter as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 16 September 1976 to 20 September 1976 (NODC Accession 7700783)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine Toxic Substance and other data were collected from bottle casts in the Bering Sea from a helicopter. Data were collected by Pacific Marine Environmental...

  8. Marine toxic substance and other data from bottle casts from NOAA Ship DISCOVERER as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1975-09-12 to 1975-11-10 (NODC Accession 7700045)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from bottle casts from NOAA Ship DISCOVERER. Data were collected by Pacific Marine Environmental Laboratory...

  9. Linking high resolution mass spectrometry data with exposure and toxicity forecasts to advance high-throughput environmental monitoring

    Data.gov (United States)

    U.S. Environmental Protection Agency — There is a growing need in the field of exposure science for monitoring methods that rapidly screen environmental media for suspect contaminants. Measurement and...

  10. Zitongdong Block

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    @@ The Zitongdong Block (Eastern Zitong Block) is located in the northwest of the Sichuan Basin. Tectonically, it is situated in the east part of Zitong Depression, southeast of mid-Longmenshan folded and faulted belt( as shown on Fig. 8 ), covering an area of 1 730 km2. The traffic is very convenient, the No. 108 national highway passes through the north of the block. Topographically, the area belongs to low hilly land at the elevation of 500-700 m.

  11. COMPUTER-BASED PREDICTION OF TOXICITY USING THE ELECTRON-CONFORMATIONAL METHOD. APPLICATION TO FRAGRANCE ALLERGENS AND OTHER ENVIRONMENTAL POLLUTANTS

    Directory of Open Access Journals (Sweden)

    Natalia N. Gorinchoy

    2012-06-01

    Full Text Available The electron-conformational (EC method is employed for the toxicophore (Tph identification and quantitative prediction of toxicity using the training set of 24 compounds that are considered as fragrance allergens. The values of a=LD50 in oral exposure of rats were chosen as a measure of toxicity. EC parameters are evaluated on the base of conformational analysis and ab initio electronic structure calculations (including solvent influence. The Tph consists of four sites which in this series of compounds are represented by three carbon and one oxygen atoms, but may be any other atoms that have the same electronic and geometric features within the tolerance limits. The regression model taking into consideration the Tph flexibility, anti-Tph shielding, and influence of out-of-Tph functional groups predicts well the experimental values of toxicity (R2 = 0.93 with a reasonable leaveone- out cross-validation.

  12. Keratinocyte-derived IL-24 plays a role in the positive feedback regulation of epidermal inflammation in response to environmental and endogenous toxic stressors

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Sun Hee [Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul 151-742 (Korea, Republic of); Choi, Dalwoong [Department of Public Health Science, Korea University, Seoul 136-701 (Korea, Republic of); Chun, Young-Jin [College of Pharmacy, Chung-Ang University, Seoul 156-756 (Korea, Republic of); Noh, Minsoo, E-mail: minsoo@alum.mit.edu [Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2014-10-15

    Keratinocytes are the major cellular components of human epidermis and play a key role in the modulating cutaneous inflammation and toxic responses. In human chronic skin diseases, the common skin inflammatory phenotypes like skin barrier disruption and epidermal hyperplasia are manifested in epidermal keratinocytes by interactions with T helper (Th) cells. To find a common gene expression signature of human keratinocytes in chronic skin diseases, we performed a whole genome microarray analysis on normal human epidermal keratinocytes (NHKs) treated with IFNγ, IL-4, IL-17A or IL-22, major cytokines from Th1, Th2, Th17 or Th22 cells, respectively. The microarray results showed that the four genes, IL-24, PDZK1IP1, H19 and filaggrin, had common expression profiles in NHKs exposed to Th cell cytokines. In addition, the acute phase pro-inflammatory cytokines, IL-1β, IL-6 and TNFα, also change the gene transcriptional profile of IL-24, PDZK1IP1, H19, and filaggrin in NHKs as those of Th cytokines. Therefore, the signature gene set, consisting of IL-24, PDZK1IP1, H19, and filaggrin, provides essential insights for understanding the process of cutaneous inflammation and toxic responses. We demonstrate that environmental toxic stressors, such as chemical irritants and ultraviolet irradiation stimulate the production of IL-24 in NHKs. IL-24 stimulates the JAK1-STAT3 and MAPK pathways in NHKs, and promotes the secretion of pro-inflammatory mediators IL-8, PGE2, and MMP-1. These results suggest that keratinocyte-derived IL-24 participates in the positive feedback regulation of epidermal inflammation in response to both endogenous and environmental toxic stressors. - Highlights: • Cutaneous inflammatory gene signature consists of PDZK1IP1, IL-24, H19 and filaggrin. • Pro-inflammatory cytokines increase IL-24 production in human keratinocytes. • Environmental toxic stressors increase IL-24 production in human keratinocytes. • IL-24 stimulates human keratinocytes to

  13. Enantiomeric separation of organophosphorus pesticides by high-performance liquid chromatography, gas chromatography and capillary electrophoresis and their applications to environmental fate and toxicity assays.

    Science.gov (United States)

    Li, Ling; Zhou, Shanshan; Jin, Lixia; Zhang, Cheng; Liu, Weiping

    2010-05-15

    In recent years, the continuous evolution of the field of stereochemistry has produced a heightened awareness of the applications of pure enantiomers of agrochemicals. This review describes reports of the enantiomeric separation of commercial organophosphorus pesticides (OPs) and the applications of these methods to research on the enantioselectivity of the toxicity and environmental fate of these compounds. Chiral OPs can be analysed by high-performance liquid chromatography (HPLC), gas chromatography (GC), and capillary electrophoresis (CE). These different separation techniques for OP enantiomers are briefly discussed, and their applications are presented.

  14. Anodonta imbecillis copper sulfate reference toxicant/food test, Clinch River - Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1997-06-01

    Reference toxicant testing using juvenile freshwater mussels was conducted as part of the CR-ERP biomonitoring study of Clinch River sediments to assess the sensitivity of test organisms and the overall performance of the test. Tests were conducted using moderately hard synthetic water spiked with known concentrations of copper as copper sulfate. Two different foods, phytoplankton and YCT-Selenastrum (YCT-S), were tested in side by side tests to compare food quality. Toxicity testing of copper sulfate reference toxicant was conducted from July 6-15, 1993. The organisms used for testing were juvenile fresh-water mussels (Anodonta imbecillis). Results from this test showed LC{sub 50} values of 0.97 and 0.84 mg Cu/L for phytoplankton and YCT-S, respectively. Previously obtained values for phytoplankton tests are 2.02 and 1.12 mg Cu/L. Too few tests have been conducted with copper as the toxicant to determine a normal range of values. Although significant reduction in growth, compared to the phytoplankton control, was seen in all treatments, including the YCT-S Control, the consequence of this observation has not been established. Ninety-day testing of juvenile mussels exhibited large variations in growth within treatment and replicate groups.

  15. Host Response to Environmental Hazards: Using Literature, Bioinformatics, and Computation to Derive Candidate Biomarkers of Toxic Industrial Chemical Exposure

    Science.gov (United States)

    2015-10-01

    routine manufacturing and industry operations in a megacity environment [8]. Inaccurate chemical inventories and inadequate regulation by centralized...effectively broadens the tools applicable to chemical exposure scenarios. BHSAI, Biotechnology HPC Software Applications Institute. 2.0 METHODS 2.1...comprising toxicity, stability, and physical state scores. Critical and high priority sub-lists were developed based on additional scoring algorithms

  16. Contaminated soil concrete blocks

    NARCIS (Netherlands)

    Korte, de A.C.J.; Brouwers, H.J.H.; Limbachiya, Mukesh C.; Kew, Hsein Y.

    2009-01-01

    According to Dutch law the contaminated soil needs to be remediated or immobilised. The main focus in this article is the design of concrete blocks, containing contaminated soil, that are suitable for large production, financial feasible and meets all technical and environmental requirements. In ord

  17. Zitongxi Block

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    @@ Zitongxi Block (Western Zitong Block), is located in Zitong County, northwest of Sichuan Province (as shown on Fig. 8 ). Geologically. it is situated in the Zitong Depression, southwest of the middle Longmenshan faulted and folded belt, covering an area of 1 830 km2. Transportation is very convenient. A crisscross network of highways run through the block and the Baocheng railway is nearby. The climate is moderate. Most area belongs to hilly land with the elevation of 500-600 m.The Tongjiang River runs across the area.

  18. Chengzikou Block

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    @@ Chengzikou Block is located in the north of Hekou district, Dongying City, Shandong Province, adjacent to Bohai Bay. It can be geographically divided into three units: onshore, transitional zone and offshore ultrashallow zone, totally covering an area of 470 km2. The southern onshore area is low and gentle in topography;the northern shallow sea is at water depths of 2-8 m below sea level, and the transitional zone occupies more than 60% of the whole block. The climate belongs to temperate zone with seasonal wind. Highways are welldeveloped here, and the traffic is very convenient. The Chengzikou Block is about 80 km away from Dongying City and 290 km from Jinan City in the south. The northern offshore area of the block is 160 km away from Longkou port in the east and only 38 km away in the west from Zhuangxi port.

  19. Longmenshan Block

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    @@ Longmenshan Block is located in Jiange County of Jiangyou City in the northwest of Sichuan Basin. covering an area of 2 628 km2. Geologically, it is situated in the Mid-Longmenshan fault and fold belt, neighbouring Zitong Depression in its southeast. There are mountains surrounding its northwest , the rest area being hilly land,with the elevation of 500-700 m. The BaoCheng railway and the No. 108 highway run through the block, the traffic is very convenient.

  20. Effects of nanomolar copper on water plants—Comparison of biochemical and biophysical mechanisms of deficiency and sublethal toxicity under environmentally relevant conditions

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, George, E-mail: george.thomas@uni.kn [Universität Konstanz, Mathematisch-Naturwissenschaftliche Sektion, Fachbereich Biologie, D-78457 Konstanz (Germany); Stärk, Hans-Joachim, E-mail: ha-jo.staerk@ufz.de [UFZ – Helmholtz Centre for Environmental Research, Department of Analytical Chemistry, Permoserstr. 15, D-04318 Leipzig (Germany); Wellenreuther, Gerd, E-mail: Gerd.wellenreuther@desy.de [HASYLAB at DESY, Notkestr. 85, 22603 Hamburg (Germany); Dickinson, Bryan C., E-mail: bryan.dickinson@gmail.com [Harvard University, Department of Chemistry and Chemical Biology, 12 Oxford Street, Cambridge, MA 02138 (United States); Küpper, Hendrik, E-mail: hendrik.kuepper@uni-konstanz.de [Universität Konstanz, Mathematisch-Naturwissenschaftliche Sektion, Fachbereich Biologie, D-78457 Konstanz (Germany); University of South Bohemia, Faculty of Biological Sciences and Institute of Physical Biology, Branišovská 31, CZ-370 05 České Budejovice (Czech Republic)

    2013-09-15

    Highlights: •We found different optimal Cu requirement for different physiological mechanisms. •Kinetics and concentration thresholds of damage mechanisms were established. •Cu toxicity caused internal Cu re-distribution and inhibition of Zn uptake. •Cu deficient plants released Cu, indicating lack of high-affinity Cu transporters. •Cu deficiency caused re-distribution of zinc in the plant. -- Abstract: Toxicity and deficiency of essential trace elements like Cu are major global problems. Here, environmentally relevant sub-micromolar concentrations of Cu (supplied as CuSO{sub 4}) and simulations of natural light- and temperature cycles were applied to the aquatic macrophyte Ceratophyllum demersum. Growth was optimal at 10 nM Cu, while PSII activity (F{sub v}/F{sub m}) was maximal around 2 nM Cu. Damage to the PSII reaction centre was the first target of Cu toxicity, followed by disturbed regulation of heat dissipation (NPQ). Only after that, electron transport through PSII (Φ{sub PSII}) was inhibited, and finally chlorophylls decreased. Copper accumulation in the plants was stable until 10 nM Cu in solution, but strongly increased at higher concentrations. The vein was the main storage site for Cu up to physiological concentrations (10 nM). At toxic levels it was also sequestered to the epidermis and mesophyll until export from the vein became inhibited, accompanied by inhibition of Zn uptake. Copper deficiency led to a complete stop of growth at “0” nM Cu after 6 weeks. This was accompanied by high starch accumulation although electron flow through PSII (Φ{sub PSII}) decreased from 2 weeks, followed by decrease in pigments and increase of non photochemical quenching (NPQ). Release of Cu from the plants below 10 nM Cu supply in the nutrient solution indicated lack of high-affinity Cu transporters, and on the tissue level copper deficiency led to a re-distribution of zinc.

  1. Toxicity challenges in environmental chemicals: Prediction of human plasma protein binding through quantitative structure-activity relationship (QSAR) models

    Science.gov (United States)

    The present study explores the merit of utilizing available pharmaceutical data to construct a quantitative structure-activity relationship (QSAR) for prediction of the fraction of a chemical unbound to plasma protein (Fub) in environmentally relevant compounds. Independent model...

  2. Hawaii Census 2000 Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer represents Census 2000 demographic data derived from the PL94-171 redistricting files and SF3. Census geographic entities include blocks, blockgroups...

  3. Reproductive toxicity parameters and biological monitoring in occupationally and environmentally boron-exposed persons in Bandirma, Turkey.

    Science.gov (United States)

    Duydu, Yalçın; Başaran, Nurşen; Üstündağ, Aylin; Aydin, Sevtap; Ündeğer, Ülkü; Ataman, Osman Yavuz; Aydos, Kaan; Düker, Yalçın; Ickstadt, Katja; Waltrup, Britta Schulze; Golka, Klaus; Bolt, Hermann M

    2011-06-01

    Boric acid and sodium borates have been considered as being "toxic to reproduction and development", following results of animal studies with high doses. Experimentally, a NOAEL (no observed adverse effect level) of 17.5 mg B/kg-bw/day has been identified for the (male) reproductive effects of boron in a multigeneration study of rats, and a NOAEL for the developmental effects in rats was identified at 9.6 mg B/kg-bw/day. These values are being taken as the basis of current EU safety assessments. The present study was conducted to investigate the reproductive effects of boron exposure in workers employed in boric acid production plant in Bandirma, Turkey. In order to characterize the external and internal boron exposures, boron was determined in biological samples (blood, urine, semen), in workplace air, in food, and in water sources. Unfavorable effects of boron exposure on the reproductive toxicity indicators (concentration, motility, morphology of the sperm cells and blood levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and total testosterone) were not observed. The mean calculated daily boron exposure (DBE) of the highly exposed group was 14.45 ± 6.57 (3.32-35.62) mg/day. These human exposures represent worst-case exposure conditions to boric acid/borates in Turkey. These exposure levels are considerably lower than exposures, which have previously led to reproductive effects in experimental animals. In conclusion, this means that dose levels of boron associated with developmental and reproductive toxic effects in animals are by far not reachable for humans under conditions of normal handling and use.

  4. Media Coverage of Toxic Risks: A Content Analysis of Pediatric Environmental Health Information Available to New and Expecting Mothers.

    Science.gov (United States)

    Mello, Susan

    2015-01-01

    Mass media play a central role in providing environmental health information to the public. Despite several decades of environmental and health communication research, the nature of environmental health information available to one of the most vulnerable populations--new and expecting mothers--has received limited attention. To address this gap, this study poses two questions: (1) How prevalent is information related to prenatal and pediatric environmental health (PPEH) in the media, and (2) how much coverage do the most concerning chemical threats to PPEH receive? A content analysis of 2,543 texts in popular media sources (i.e., the Associated Press [AP], parenting magazines, and parenting websites) from September 2012 to February 2013 revealed that roughly three pieces of PPEH information were made available to mothers daily. Prior research has shown that media coverage of environmental health issues has decreased over the years; however, these results suggest that at-risk populations are likely to encounter this type of information in the media. Also, while certain chemicals received ample coverage (i.e., pesticides, cigarette smoke, mercury), other issues deemed concerning by federal agencies did not (i.e., lead, phthalates). This study also introduces a novel method for harvesting online content encountered incidentally. Implications of these findings for communication research and practice are discussed.

  5. Recent Trends in Rapid Environmental Monitoring of Pathogens and Toxicants: Potential of Nanoparticle-Based Biosensor and Applications

    Directory of Open Access Journals (Sweden)

    Preeyaporn Koedrith

    2015-01-01

    Full Text Available Of global concern, environmental pollution adversely affects human health and socioeconomic development. The presence of environmental contaminants, especially bacterial, viral, and parasitic pathogens and their toxins as well as chemical substances, poses serious public health concerns. Nanoparticle-based biosensors are considered as potential tools for rapid, specific, and highly sensitive detection of the analyte of interest (both biotic and abiotic contaminants. In particular, there are several limitations of conventional detection methods for water-borne pathogens due to low concentrations and interference with various enzymatic inhibitors in the environmental samples. The increase of cells to detection levels requires long incubation time. This review describes current state of biosensor nanotechnology, the advantage over conventional detection methods, and the challenges due to testing of environmental samples. The major approach is to use nanoparticles as signal reporter to increase output rather than spending time to increase cell concentrations. Trends in future development of novel detection devices and their advantages over other environmental monitoring methodologies are also discussed.

  6. National Air Toxic Assessments (NATA) Results

    Data.gov (United States)

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

  7. Amperometric screen-printed algal biosensor with flow injection analysis system for detection of environmental toxic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Shitanda, Isao [Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan)], E-mail: shitanda@rs.noda.tus.ac.jp; Takamatsu, Satoshi; Watanabe, Kunihiro; Itagaki, Masayuki [Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan)

    2009-08-30

    A screen-printed algal biosensor was fabricated for evaluation of toxicity of chemicals. An algal ink was prepared by mixing unicellular microalga Chlorella vulgaris cells, carbon nanotubes and sodium alginate solution. The algal ink was immobilized directly on a screen-printed carbon electrode surface using screen-printing technique. Photosynthetically generated oxygen of the immobilized algae was monitored amperometically. Responses of the algal biosensor to four toxic compounds, 6-chloro-N-ethyl-N-isopropyl-1,3,5-triazine-2,4-diamine (atrazine) and 3-(3,4-dichlorophenyl)-1,1-diethylurea (DCMU) were evaluated as inhibition ratios of the reduction current. The concentrations that gave 50% inhibition of the oxygen reduction current (IC{sup '}{sub 50}) for atrazine and DCMU were 12 and 1 {mu}mol dm{sup -3}, respectively. In comparison with the conventional algal biosensors, in which the algal cells were entrapped in an alginate gel and immobilized on the surface of a transparent indium tin oxide electrode, the present sensor is much smaller and less expensive, with the shorter assay time.

  8. Linking high resolution mass spectrometry data with exposure and toxicity forecasts to advance high-throughput environmental monitoring

    Science.gov (United States)

    There is a growing need in the field of exposure science for monitoring methods that rapidly screen environmental media for suspect contaminants. Measurement and analysis platforms, based on high resolution mass spectrometry (HRMS), now exist to meet this need. Here we describe r...

  9. Enrichment, geo-accumulation and risk surveillance of toxic metals for different environmental compartments from Mehmood Booti dumping site, Lahore city, Pakistan.

    Science.gov (United States)

    Aiman, Umme; Mahmood, Adeel; Waheed, Sidra; Malik, Riffat Naseem

    2016-02-01

    The present study was designed to probe the levels of heavy metals (Cd, Pb, Cr, Mn, Cu, Ni, Zn and Fe) for different environmental matrices (ground water, wastewater, sediment, soil, dust and leachates). Impact of solid waste dumping site on nearby human population has also been assessed. The results revealed that concentration of Pb, Fe, Cd, Mn and Cu surpassed the permissible limits of World Health Organization (WHO) and US Environmental Protection Agency (USEPA) in water, soil, sediments, while aforesaid metals in wastewater were above the National Environmental Quality Standards (NEQS). Our results for enrichment factor (EF) and geo-accumulation (I(geo)) values revealed that soils and sediments were contaminated with Cd, Pb, Ni and Mn. The Cd content caused a considerably high potential ecological risk (E(r)(i) ≥ 320) in soil and sediments. Pb and Cd caused high health risk (HR > 1) to local residents via dust and drinking water intake. Potential cancer risk for Pb was higher than USEPA standard values (1.0E-06-1.0E-04) through water intake. The Mehmood Booti dumping site is a potential source of toxic pollutants contamination to the surrounding population. It is recommended to take proper actions for its management to resolve this issue.

  10. Chadong Block

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    @@ The Chadong Block, located in the east of Qaidam Basin, Qinghai Province, covers an area of 12 452 km2. It is bounded by Kunlum Mountains in the south and the northwest is closely adjacent to Aimunike Mountain.Rivers are widely distributed, which always run in NWSE direction, including the Sulunguole, Qaidam and Haluwusu Rivers. The traffic condition is good, the Qinghai-Tibet highway stretching through the whole area and the Lan-Qing railway, 20-50 km away from the block, passing from north to west. A lot of Mongolia minority people have settled there, of which herdsmen always live nearby the Qaidam River drainage area.

  11. Genetic susceptibility to environmental toxicants: the interface between human and experimental studies in the development of new toxicological concepts.

    Science.gov (United States)

    Thier, Ricarda; Golka, Klaus; Brüning, Thomas; Ko, Yon; Bolt, Hermann M

    2002-02-28

    The growing knowledge of the genetic polymorphisms of enzymes metabolising xenobiotics in humans and their connections with individual susceptibility towards toxicants has created new and important interfaces between human epidemiology and experimental toxicology. The results of molecular epidemiological studies may provide new hypotheses and concepts, which call for experimental verification, and experimental concepts may obtain further proof by molecular epidemiological studies. If applied diligently, these possibilities may be combined to lead to new strategies of human-oriented toxicological research. This overview will present some outstanding examples for such strategies taken from the practically very important field of occupational toxicology. The main focus is placed on the effects of enzyme polymorphisms of the xenobiotic metabolism in association with the induction of bladder cancer and renal cell cancer after exposure to occupational chemicals. Also, smoking and induction of head and neck squamous cell cancer are considered.

  12. Toxicity Reference Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Toxicity Reference Database (ToxRefDB) contains approximately 30 years and $2 billion worth of animal studies. ToxRefDB allows scientists and the interested...

  13. Water soluble nano-scale transient material germanium oxide for zero toxic waste based environmentally benign nano-manufacturing

    Science.gov (United States)

    Almuslem, A. S.; Hanna, A. N.; Yapici, T.; Wehbe, N.; Diallo, E. M.; Kutbee, A. T.; Bahabry, R. R.; Hussain, M. M.

    2017-02-01

    In the recent past, with the advent of transient electronics for mostly implantable and secured electronic applications, the whole field effect transistor structure has been dissolved in a variety of chemicals. Here, we show simple water soluble nano-scale (sub-10 nm) germanium oxide (GeO2) as the dissolvable component to remove the functional structures of metal oxide semiconductor devices and then reuse the expensive germanium substrate again for functional device fabrication. This way, in addition to transiency, we also show an environmentally friendly manufacturing process for a complementary metal oxide semiconductor (CMOS) technology. Every year, trillions of complementary metal oxide semiconductor (CMOS) electronics are manufactured and billions are disposed, which extend the harmful impact to our environment. Therefore, this is a key study to show a pragmatic approach for water soluble high performance electronics for environmentally friendly manufacturing and bioresorbable electronic applications.

  14. Water soluble nano-scale transient material germanium oxide for zero toxic waste based environmentally benign nano-manufacturing

    KAUST Repository

    Almuslem, A. S.

    2017-02-14

    In the recent past, with the advent of transient electronics for mostly implantable and secured electronic applications, the whole field effect transistor structure has been dissolved in a variety of chemicals. Here, we show simple water soluble nano-scale (sub-10 nm) germanium oxide (GeO) as the dissolvable component to remove the functional structures of metal oxide semiconductor devices and then reuse the expensive germanium substrate again for functional device fabrication. This way, in addition to transiency, we also show an environmentally friendly manufacturing process for a complementary metal oxide semiconductor (CMOS) technology. Every year, trillions of complementary metal oxide semiconductor (CMOS) electronics are manufactured and billions are disposed, which extend the harmful impact to our environment. Therefore, this is a key study to show a pragmatic approach for water soluble high performance electronics for environmentally friendly manufacturing and bioresorbable electronic applications.

  15. Exposure to Crystal Violet, Its Toxic, Genotoxic and Carcinogenic Effects on Environment and Its Degradation and Detoxification for Environmental Safety.

    Science.gov (United States)

    Mani, Sujata; Bharagava, Ram Naresh

    2016-01-01

    Crystal Violet (CV), a triphenylmethane dye, has been extensively used in human and veterinary medicine as a biological stain, as a textile dye in textile processing industries and also used to provide a deep violet color to paints and printing ink. CV is also used as a mutagenic and bacteriostatic agent in medical solutions and antimicrobial agent to prevent the fungal growth in poultry feed. Inspite of its many uses, CV has been reported as a recalcitrant dye molecule that persists in environment for a long period and pose toxic effects in environment. It acts as a mitotic poison, potent carcinogen and a potent clastogene promoting tumor growth in some species of fish. Thus, CV is regarded as a biohazard substance. Although, there are several physico-chemical methods such as adsorption, coagulation and ion-pair extraction reported for the removal of CV, but these methods are insufficient for the complete removal of CV from industrial wastewaters and also produce large quantity of sludge containing secondary pollutants. However, biological methods are regarded as cost-effective and eco-friendly for the treatment of industrial wastewaters, but these methods also have certain limitations. Therefore, there is an urgent need to develop such eco-friendly and cost-effective biological treatment methods, which can effectively remove the dye from industrial wastewaters for the safety of environment, as well as human and animal health.

  16. Disposable electrochemical DNA biosensor for environmental monitoring of toxicant 2-aminoanthracene in the presence of chlorine in real samples

    Indian Academy of Sciences (India)

    R Motaghed Mazhabi; M Arvand

    2014-07-01

    A simple procedure for the voltammetric detection of the DNA damage using a disposable electrochemical DNA biosensor is reported. The DNA biosensor is assembled by immobilizing the double stranded calf thymus DNA (dsDNA) on the surface of a disposable carbon screen-printed electrode. The interaction of 2-aminoanthracene (2-AA) with calf thymus dsDNA was studied electrochemically based on the oxidation signals of guanine (G) and adenine (A) by using square wave voltammetry (SWV) at screen printed electrode (SPE). The oxidation signals of the guanine and adenine bases, obtained by a square wave voltammetric scan, were used as analytical signal to detect the DNA damage. The presence of this aromatic amine compound with affinity for nucleic acids was measured by its effect on the guanine and adenine oxidation peaks. The response was obtained in the range of 0.05-20 mg L-1 for 2-AA concentration on dsDNA-modified SPE. This test has been used due to its rapid, easy handling and cost effective responses for the toxicity assessment in real water and bleach solution samples.

  17. Behavior toxicity to Caenorhabditis elegans transferred to the progeny after exposure to sulfamethoxazole at environmentally relevant concentrations

    Institute of Scientific and Technical Information of China (English)

    Zhenyang Yu; Lei Jiang; Daqiang Yin

    2011-01-01

    Sulfamethoxazole (SMX) is one of the most common detected antibiotics in the environment. In order to study whether SMX can affect behavior and growth and whether these effects could be transferred to the progeny, Caenorhabditis elegans was exposed at environmentally relevant concentrations for 24, 48, 72 and 96 hr, respectively. After exposure, the exposed parent generation (Po) was measured for behavior and growth indicators, which were presented as percentage of controls (POC). Then their corresponding unexposed progeny (F1) was separated and measured for the same indicators. The lowest POC for Po after 96 hr-exposure at 100 mg/L were 37.8%, 12.7%, 45.8% and 70.1% for body bending frequency (BBF), reversal movement (RM), Omega turns (OT) and body length (BL), respectively. And F1 suffered defects with the lowest POC as 55.8%, 24.1%, 48.5% and 60.7% for BBF, RM, OT and BL, respectively. Defects in both Po and F1 showed a time- and concentration-dependent fashion and behavior indicators showed better sensitivity than growth indicator. The observed effects on F1 demonstrated the transferable properties of SMX. Defects of SMX at environmental concentrations suggested that it is necessary to perform further systematical studies on its ecological risk in actual conditions.

  18. The environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin disrupts morphogenesis of the rat pre-implantation embryo

    Directory of Open Access Journals (Sweden)

    Albertini David F

    2008-01-01

    Full Text Available Abstract Background Environmental toxicants, whose actions are often mediated through the aryl hydrocarbon receptor (AhR pathway, pose risks to the health and well-being of exposed species, including humans. Of particular concern are exposures during the earliest stages of development that while failing to abrogate embryogenesis, may have long term effects on newborns or adults. The purpose of this study was to evaluate the effect of maternal exposure to the AhR-specific ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD on the development of rat pre-implantation embryos with respect to nuclear and cytoskeletal architecture and cell lineage allocation. Results We performed a systematic 3 dimensional (3D confocal microscopy analysis of rat pre-implantation embryos following maternal exposure to environmentally relevant doses of TCDD. Both chronic (50 ng/kg/wk for 3 months and acute (50 ng/kg and 1 μg/kg at proestrus maternal TCDD exposure disrupted morphogenesis at the compaction stage (8–16 cell, with defects including monopolar spindle formation, f-actin capping and fragmentation due to aberrant cytokinesis. Additionally, the size, shape and position of nuclei were modified in compaction stage pre-implantation embryos collected from treated animals. Notably, maternal TCDD exposure did not compromise survival to blastocyst, which with the exception of nuclear shape, were morphologically similar to control blastocysts. Conclusion We have identified the compaction stage of pre-implantation embryogenesis as critically sensitive to the effects of TCDD, while survival to the blastocyst stage is not compromised. To the best of our knowledge this is the first in vivo study to demonstrate a critical window of pre-implantation mammalian development that is vulnerable to disruption by an AhR ligand at environmentally relevant doses.

  19. Changes in mobility of toxic elements during the production of phosphoric acid in the fertilizer industry of Huelva (SW Spain) and environmental impact of phosphogypsum wastes.

    Science.gov (United States)

    Pérez-López, Rafael; Alvarez-Valero, Antonio M; Nieto, José Miguel

    2007-09-30

    Presently, about 3 million tonnes of phosphogypsum are being generated annually in Spain as by-product from phosphoric acid in a fertilizer factory located in Huelva (southwestern Iberian Peninsula). Phosphate rock from Morocco is used as raw material in this process. Phosphogypsum wastes are stored in a stack containing 100Mt (approximately 1200ha of surface) over salt marshes of an estuary formed by the confluence of the Tinto and Odiel rivers, less than 1km away from the city centre. A very low proportion of this waste is used to improve fertility of agricultural soils in the area of the Guadalquivir river valley (Seville, SW Spain). The chemical speciation of potentially toxic elements (Ba, Cd, Cu, Ni, Sr, U and Zn) in phosphogypsum and phosphate rock was performed using the modified BCR-sequential extraction procedure, as described by the European Community Bureau of Reference (1999). This study has been done with the main of: (1) evaluate changes in the mobility of metals during the production of phosphoric acid; (2) estimate the amount of mobile metals that can affect the environmental surrounding; and (3) verify the environmentally safe use of phosphogypsum as an amendment to agricultural soils. The main environmental concern associated to phosphoric acid production is that Uranium, a radiotoxic element, is transferred from the non-mobile fraction in the phosphate rock to the bioavailable fraction in phosphogypsum in a rate of 23%. Around 21% of Ba, 6% of Cu and Sr, 5% of Cd and Ni, and 2% of Zn are also contained in the water-soluble phase of the final waste. Considering the total mass of phosphogypsum, the amount of metals easily soluble in water is approximately 6178, 3089, 1931, 579, 232, 193 and 77t for Sr, U, Ba, Zn, Ni, Cu and Cd, respectively. This gives an idea of the pollution potential of this waste.

  20. Changes in mobility of toxic elements during the production of phosphoric acid in the fertilizer industry of Huelva (SW Spain) and environmental impact of phosphogypsum wastes

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Lopez, Rafael [Department of Geology, University of Huelva, Campus ' El Carmen' , E-21071 Huelva (Spain)], E-mail: rafael.perez@dgeo.uhu.es; Alvarez-Valero, Antonio M.; Nieto, Jose Miguel [Department of Geology, University of Huelva, Campus ' El Carmen' , E-21071 Huelva (Spain)

    2007-09-30

    Presently, about 3 million tonnes of phosphogypsum are being generated annually in Spain as by-product from phosphoric acid in a fertilizer factory located in Huelva (southwestern Iberian Peninsula). Phosphate rock from Morocco is used as raw material in this process. Phosphogypsum wastes are stored in a stack containing 100 Mt (approximately 1200 ha of surface) over salt marshes of an estuary formed by the confluence of the Tinto and Odiel rivers, less than 1 km away from the city centre. A very low proportion of this waste is used to improve fertility of agricultural soils in the area of the Guadalquivir river valley (Seville, SW Spain). The chemical speciation of potentially toxic elements (Ba, Cd, Cu, Ni, Sr, U and Zn) in phosphogypsum and phosphate rock was performed using the modified BCR-sequential extraction procedure, as described by the European Community Bureau of Reference (1999). This study has been done with the main of: (1) evaluate changes in the mobility of metals during the production of phosphoric acid; (2) estimate the amount of mobile metals that can affect the environmental surrounding; and (3) verify the environmentally safe use of phosphogypsum as an amendment to agricultural soils. The main environmental concern associated to phosphoric acid production is that Uranium, a radiotoxic element, is transferred from the non-mobile fraction in the phosphate rock to the bioavailable fraction in phosphogypsum in a rate of 23%. Around 21% of Ba, 6% of Cu and Sr, 5% of Cd and Ni, and 2% of Zn are also contained in the water-soluble phase of the final waste. Considering the total mass of phosphogypsum, the amount of metals easily soluble in water is approximately 6178, 3089, 1931, 579, 232, 193 and 77 t for Sr, U, Ba, Zn, Ni, Cu and Cd, respectively. This gives an idea of the pollution potential of this waste.

  1. Environmental Evaluation of Dust Stabilizer Products

    Science.gov (United States)

    2007-08-01

    the amphipod (Hyalella azteca ) and the water flea (D. magna). In preliminary studies, significant mortality in D. magna was observed at concentrations...inhibition concentration (IC50) value for reproduction was 9.07 mg/L Durasoil® (BES 2005d). In sediments, significant mortality was observed in H. azteca ...definitive bioassay with the amphipod Hyalella azteca . Pleasant Hill, CA: Block Environmental Services. ______. 2005f. Soil toxicity results for Durasoil

  2. Environmental and human exposure assessment monitoring of communities near an abandoned mercury mine in the Philippines: a toxic legacy.

    Science.gov (United States)

    Maramba, Nelia P C; Reyes, Jose Paciano; Francisco-Rivera, Ana Trinidad; Panganiban, Lynn Crisanta R; Dioquino, Carissa; Dando, Nerissa; Timbang, Rene; Akagi, Hirokatsu; Castillo, Ma Teresa; Quitoriano, Carmela; Afuang, Maredith; Matsuyama, Akito; Eguchi, Tomomi; Fuchigami, Youko

    2006-10-01

    Abandoned mines are an important global concern and continue to pose real or potential threats to human safety and health including environmental damage/s. Very few countries had government mine regulation and reclamation policies until the latter part of the century where legal, financial and technical procedures were required for existing mining operations. Major reasons for mine closure may be mainly due to poor economies of the commodity making mining unprofitable, technical difficulties and national security. If the mine is abandoned, more often than not it is the government that shoulders the burden of clean-up, monitoring and remediation. The topic of abandoned mines is complex because of the associated financial and legal liability implications. Abandoned mercury mines have been identified as one of the major concerns because of their significant long-term environmental problems. Primary mercury production is still ongoing in Spain, Kyrgzystan, China, Algeria, Russia and Slovakia while world production declined substantially in the late 1980s. In the Philippines, the mercury mine located southeast of Manila was in operation from 1955 to 1976, before ceasing operation because of the decline in world market price for the commodity. During this time, annual production of mercury was estimated to be about 140,000 kg of mercury yearly. Approximately 2,000,000 t of mine-waste calcines (retorted ore) were produced during mining and roughly 1,000,000 t of these calcines were dumped into nearby Honda Bay to construct a jetty to facilitate mine operations where about 2000 people reside in the nearby three barangays. In October, 1994 the Department of Health received a request from the Provincial Health Office for technical assistance relative to the investigation of increasing complaints of unusual symptoms (e.g. miscarriages, tooth loss, muscle weakness, paralysis, anemia, tremors, etc.) among residents of three barangays. Initial health reports revealed significant

  3. Acute exposure to fenthion in juveniles of white cachama (Piaractus brachypomus: toxic effects, changes in cholinesterase activity and potential use in environmental monitoring

    Directory of Open Access Journals (Sweden)

    Borbón Javier F.

    2012-03-01

    Full Text Available Fenthion is an organophosphate insecticide used worldwide that may pollute waters after itsapplication causing potential problems in public health and poisoning in domestic and wildlifeanimals. Objective: to evaluate toxic effects, butyrylcholinesterase activity (BChE and use inenvironmental monitoring, 34 juveniles of white cachama (Piaractus brachypomus were distributedin 3 groups (control, 0,13 ppm and 2 ppm fenthion for 96 h. Materials and methods: fishwere exposed in 10-gallon tanks; symptoms, gross lesions post-mortem, viscerosomatic index(VSI and plasma BChE activity were evaluated. Mean comparisons for each variable amongtreatments were performed (ANOVA, α=0,05. Results: severe signs were seen in 3 specimens(3/11 of 2 ppm fenthion between 11 and 34 h of exposure. These signs were frantic swimming,muscle tremors and loss of swimming axis. In 0,13 ppm, mild to moderate signs (tremors andcaudal fin flapping were observed in some of the fish. The VSI (control = 5,3 ± 0,5; 0,13 ppm= 6,9 ± 0,3 and 2 ppm = 7,3 ± 0,6 was significantly different between exposed to fenthion andcontrols. BChE activity (control = 185,0 ± 20,4; 0,13 ppm = 12,5 ± 2,3 and 2 ppm = 9,8 ± 1,8nmoles / ml plasma / min showed significant inhibition in exposed to fenthion as compared tocontrols. Conclusions: the present work confirmed the toxic effects of fenthion in white cachamajuveniles. Results found in BChE activity suggest its use in environmental monitoring as a goodbiomarker of organophosphates waterborne exposure.

  4. Association between Environmental Dioxin-Related Toxicants Exposure and Adverse Pregnancy Outcome: Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Xinjuan Pan

    2015-02-01

    Full Text Available Dioxin-related compounds are associated with teratogenic and mutagenic risks in laboratory animals, and result in adverse pregnancy outcomes. However, there were inconsistent results in epidemiology studies. In view of this difference, we conducted a systematic review and meta-analysis to examine this association and to assess the heterogeneity among studies. Comprehensive literature searches were performed to search for relevant articles published in English up to 15 May 2012. In total, we identified 15 studies which included 9 cohort and 6 case control studies. The Cochrane Q test and index of heterogeneity (I 2 were used to evaluate heterogeneity. In either cohort studies (I2 =0.89, p<0.0001 or case control studies (I 2 =0.69, p=0.02, significant heterogeneity of risk estimates were observed. Subgroup analyses found no significant increased risk of adverse pregnancy outcome with air dioxin-related compounds exposure (RR=0.99, 95% CI:0.85–1.16, no significant increased risk of spontaneous abortion (SAB with exposure to food dioxin-related compounds (RR=1.05, 95% CI:0.80–1.37, higher significant risks of low birth weight (LBW with exposure to food dioxin-related compounds (RR=1.55, 95% CI:1.24–1.94, and higher significant risks of birth defects with maternal solid contaminants dioxin exposure (OR=1.24, 95% CI:1.19–1.29. In conclusion, more evidences are needed to confirm the association between environmental dioxin-related compounds exposure and pregnancy outcome.

  5. Environmental Toxicity of Several Different Pesticides Single or Mixed Micro-Emulsion%不同农药单剂及混配微乳剂的环境毒性研究

    Institute of Scientific and Technical Information of China (English)

    高越; 张润祥; 王振; 封云涛; 范仁俊

    2011-01-01

    为了研究高效氯氰菊酯、阿维菌素、甲维盐等9种单剂或混配微乳剂的安全性,笔者测试了其对环境生物的毒性大小.根据,对斑马鱼、鹌鹑、蜜蜂、桑蚕分别采用半静水式鱼毒测定法、经口染毒法、接触染毒法、食下毒叶法进行测试.在鱼毒性方面,0.2%高渗甲维盐、3%啶虫脒和20%阿维·杀虫单微乳剂表现为低或中毒,其余药剂均表现为高毒或剧毒;在鸟毒性方面,4.5%高效氯氰菊酯微乳剂表现为高毒,其余药剂均表现为低毒或中毒;在蜜蜂毒性方面,0.2%高渗甲维盐和3%啶虫脒微乳剂表现为低毒或中毒,其余均表现为高毒;在桑蚕毒性方面,所有药剂均表现为高毒或剧毒.说明啶虫脒和低含量甲维盐对鱼、鸟、蜂、蚕毒性较低,而拟除虫菊酯类杀虫剂、阿维菌素及高含量甲维盐风险性较高,在施用时应远离鱼塘、蜂场及桑树.%In order to study the safety of beta-cypermethrin, avermectin, emamectin benzoate, et al, 9 single or mixed micro-emulsion, the authors tested their environmental toxicity.Using semi-hydrostatic-type, oral exposure method, food intake method, contact exposure method to test the toxicity to fish, bird, honeybees,silkworm, respectivitly according to 'The guidelines of chemical pesticides environmental safety evaluation'.On the toxicity to fish, 0.2% hypertonic emamectin benzoate, 3% acetamiprid and 20% avermectin.monosultap were evaluated as 'low toxic class' or 'moderate toxic class', others were 'high toxic class' or 'hypertoxic class'; on the bird toxicity, 4.5% beta-cypermethrin was evaluated as 'high toxic class', others were 'low toxic class' or ' moderate toxic class'; on the toxicity to honeybees, 0.2% hypertonic emamectin benzoate and 3% acetamiprid were evaluated as ' low toxic class' or 'moderate toxic class', others were 'high toxic class';on the toxicity to silkworm, all the pesticides were evaluated as ' high toxic class' or

  6. Enzymatic nanoreactors for environmentally benign biotransformations. 1. Formation and catalytic activity of supramolecular complexes of laccase and linear-dendritic block copolymers.

    Science.gov (United States)

    Gitsov, Ivan; Hamzik, James; Ryan, Joseph; Simonyan, Arsen; Nakas, James P; Omori, Shigetoshi; Krastanov, Albert; Cohen, Tomer; Tanenbaum, Stuart W

    2008-03-01

    We describe the construction of enzymatic nanoreactors through noncovalent envelopment of a glycoprotein by amphiphilic linear-dendritic AB or ABA copolymers. The synthetic procedure is based on the regioselective adsorption of dendritic poly(benzyl ether)-block-linear poly(ethylene glycol)-block-dendritic poly(benzyl ether) or linear poly(ethylene oxide)-block-dendritic poly(benzyl ether) copolymers onto the oxidative enzyme laccase from Trametes versicolor in aqueous medium. The complexes formed have improved catalytic activity compared with the native enzyme (77-85 nkat/mL vs 60 nkat/mL, respectively) and are more stable at elevated temperatures up to 70 degrees C. Experiments with deglycosylated laccase confirm that the glycoside fragments in the native enzyme serve as the anchor sites for the linear-dendritic copolymers. The enzymatic nanoreactors are able to effectively oxidize series of substrates: phenolic compounds (syringaldazine) and hydrophobic polyaromatic hydrocarbons (anthracene and benzo[a]pyrene) under "green" chemistry conditions.

  7. Aircraft Environmental System Mechanic, 2-9. Block IV--Utility Systems and Flight Line Maintenance. Military Curriculum Materials for Vocational and Technical Education.

    Science.gov (United States)

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This publication contains a teaching guide and student instructional materials for conducting a high school or adult vocational education course to train persons to perform duties as an aircraft environmental systems mechanic. The instructional design for this course is self-paced and/or small group-paced. Instructor materials contained in the…

  8. Genetic susceptibility to environmental toxicants

    DEFF Research Database (Denmark)

    2001-01-01

    of their meaning. A potential for inadvertently raising concerns over the effect of chemicals in experimental animals or man, or even the intentional misrepresentation of results to suggest chemicals are “playing” with our genes is enormous. History has shown that some individuals and groups in society are willing...

  9. Environmental Risk Assessment Based on High-Resolution Spatial Maps of Potentially Toxic Elements Sampled on Stream Sediments of Santiago, Cape Verde

    Directory of Open Access Journals (Sweden)

    Marina M. S. Cabral Pinto

    2014-10-01

    Full Text Available Geochemical mapping is the base knowledge to identify the regions of the planet with critical contents of potentially toxic elements from either natural or anthropogenic sources. Sediments, soils and waters are the vehicles which link the inorganic environment to life through the supply of essential macro and micro nutrients. The chemical composition of surface geological materials may cause metabolic changes which may favor the occurrence of endemic diseases in humans. In order to better understand the relationships between environmental geochemistry and public health, we present environmental risk maps of some harmful elements (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, V, and Zn in the stream sediments of Santiago, Cape Verde, identifying the potentially harmful areas in this island. The Estimated Background Values (EBV of Cd, Co, Cr, Ni and V were found to be above the Canadian guidelines for any type of use of stream sediments and also above the target values of the Dutch and United States guidelines. The Probably Effect Concentrations (PEC, above which harmful effects are likely in sediment dwelling organisms, were found for Cr and Ni. Some associations between the geological formations of the island and the composition of stream sediments were identified and confirmed by descriptive statistics and by Principal Component Analysis (PCA. The EBV spatial distribution of the metals and the results of PCA allowed us to establish relationships between the EBV maps and the geological formations. The first two PCA modes indicate that heavy metals in Santiago stream sediments are mainly originated from weathering of underlying bedrocks. The first metal association (Co, V, Cr, and Mn; first PCA mode consists of elements enriched in basic rocks and compatible elements. The second association of variables (Zn and Cd as opposed to Ni; second PCA mode appears to be strongly controlled by the composition of alkaline volcanic rocks and pyroclastic rocks. So, the

  10. Toxic Release Inventory Chemicals by Groupings

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Toxics Release Inventory (TRI) makes available information for more than 600 toxic chemicals that are being used, manufactured, treated, transported, or released...

  11. Static renewal tests using Anodonta imbecillus (freshwater mussels). Anodonta imbecillis copper sulfate reference toxicant test, Clinch River-Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1993-12-31

    Reference toxicant testing using juvenile freshwater mussels was conducted as part of the CR-ERP biomonitoring study of Clinch River sediments to assess the sensitivity of test organisms and the overall performance of the test. Tests were conducted using moderately hard synthetic water spiked with known concentrations of copper as copper sulfate. Toxicity testing of copper sulfate reference toxicant was conducted from May 12--21, 1993. The organisms used for testing were juvenile fresh-water mussels (Anodonta imbecillis). Results from this test showed an LC{sub 50} value of 1.12 mg Cu/L which is lower than the value of 2.02 mg Cu/L obtained in a previous test. Too few tests have been conducted with copper as the toxicant to determine a normal range of values. Attachments to this report include: Toxicity test bench sheets and statistical analyses; Copper analysis request and results; and Personnel training documentation.

  12. The delay of the environmental licensing in oil activities and legal implications regarding the oil block; O atraso do licenciamento ambiental nas atividades petroliferas e as implicacoes atinentes ao cumprimento de prazo de bloco licitados

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcante, Hellen Priscilla Marinho; Xavier, Yanko Marcius de Alencar [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2012-07-01

    This work intends to demonstrate how the delay in issuing environmental licenses by the appropriate bodies affect the correct fulfillment of the exploratory phase of blocks already bid and rendered to the lessees. Thus, it will be conducted a study of the pertaining legislation to the subject, such as Law n. 6.938/81 and its recent amendment by Complementary Law n. 140/2011, as well as the Resolutions issued by the National Environmental Council (CONAMA), addressing the vital importance of the environmental licensing process to the preservation of the environment ante the installation of potentially harmful activities. It is also acknowledged, through the analysis of articles and paragraphs, that there is a legal gap concerning the deadline for issuance of certain documents required to start the licensing procedure by the companies, which ultimately jeopardizes the fulfillment of their exploration activities in due time. Furthermore, there is not a provision regarding the return of the deadline to the lessee when it is suspended or extended due to licensing delays for reasons beyond its control, which cannot lack a reasonable answer. Therefore, as a conclusion, it will be presented a possible solution, so as to ensure the proper accomplishment of the oil activities combined with the preservation of the environment. (author)

  13. Gulf of Mexico mud toxicity limitations

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, H.E.; Beardmore, D.H. (Phillips Petroleum Co., Bartlesville, OK (USA)); Stewart, W.S. (Drilling Specialties Co. (US))

    1989-10-01

    Because of the Environmental Protection Agency's recent toxicity limits on drilling mud discharges for offshore Gulf of Mexico, Phillips Petroleum conducted a mud toxicity study based on both field and lab tests. The study, discussed in this article, found the polyanionic cellulose-sulfomethylated quebracho-chrome lignosulfonate mud Phillips had been using would comfortably pass the toxicity limitations. The study also found barite and thinners were of low toxicity, and hydrocarbons and surfactants were highly toxic.

  14. EnviroAtlas - Milwaukee, WI - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Milwaukee, WI EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  15. EnviroAtlas - Fresno, CA - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Fresno, CA EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  16. EnviroAtlas - Portland, OR - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Portland, OR EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  17. EnviroAtlas - Cleveland, OH - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Cleveland, OH EnviroAtlas community. The block groups are from the US Census Bureau and are included/excluded...

  18. EnviroAtlas - Paterson, NJ - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Paterson, NJ EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  19. EnviroAtlas - Memphis, TN - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Memphis, TN EnviroAtlas community. The block groups are from the US Census Bureau and are included/excluded based...

  20. EnviroAtlas - Phoenix, AZ - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Phoenix, AZ EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  1. Ultrasound guided supraclavicular block.

    LENUS (Irish Health Repository)

    Hanumanthaiah, Deepak

    2013-09-01

    Ultrasound guided regional anaesthesia is becoming increasingly popular. The supraclavicular block has been transformed by ultrasound guidance into a potentially safe superficial block. We reviewed the techniques of performing supraclavicular block with special focus on ultrasound guidance.

  2. Dilated cardiomyopathy and left bundle branch block associated with ingestion of colloidal gold and silver is reversed by British antiLewisite and vitamin E: the potential toxicity of metals used as health supplements.

    Science.gov (United States)

    Archer, Stephen Lawrence

    2008-05-01

    A case of left bundle branch block and a dilated, nonhypertrophic cardiomyopathy associated with ingestion of colloidal gold and silver as an 'energy tonic' is described. The cardiac disease was reversed within two months by a course of dimercaprol (Akorn Inc, USA) (British antiLewisite) and vitamin E. This is the first case of gold and silver cardiomyopathy in humans, and highlights the risks of these colloidal metal 'health supplements'.

  3. Use of porcine vaginal tissue ex-vivo to model environmental effects on vaginal mucosa to toxic shock syndrome toxin-1

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Catherine C.; Baccam, Mekhine [Feminine Care Global Product Stewardship, 6110 Center Hill Road, The Procter and Gamble Company, Cincinnati, OH 45224 (United States); Mantz, Mary J. [Dows Institute for Dental Research, The University of Iowa, Iowa City, IA 52242 (United States); Osborn, Thomas W.; Hill, Donna R. [Feminine Care Product Development, 6110 Center Hill Road, The Procter and Gamble Company, Cincinnati, OH 45224 (United States); Squier, Christopher A. [Dows Institute for Dental Research, The University of Iowa, Iowa City, IA 52242 (United States)

    2014-01-15

    Menstrual toxic shock syndrome (mTSS) is a rare, recognizable, and treatable disease that has been associated with tampon use epidemiologically. It involves a confluence of microbial risk factors (Staphylococcus aureus strains that produce the superantigen—TSST-1), as well as environmental characteristics of the vaginal ecosystem during menstruation and host susceptibility factors. This paper describes a series of experiments using the well-characterized model of porcine vaginal mucosa ex-vivo to assess the effect of these factors associated with tampon use on the permeability of the mucosa. The flux of radiolabeled TSST-1 and tritiated water ({sup 3}H{sub 2}O) through porcine vaginal mucosa was determined at various temperatures, after mechanical disruption of the epithelial surface by tape stripping, after treatment with surfactants or other compounds, and in the presence of microbial virulence factors. Elevated temperatures (42, 47 and 52 °C) did not significantly increase flux of {sup 3}H{sub 2}O. Stripping of the epithelial layers significantly increased the flux of labeled toxin in a dose-dependent manner. Addition of benzalkonium chloride (0.1 and 0.5%) and glycerol (4%) significantly increased the flux of {sup 3}H{sub 2}O but sodium lauryl sulfate at any concentration tested did not. The flux of the labeled toxin was significantly increased in the presence of benzalkonium chloride but not Pluronic® L92 and Tween 20 and significantly increased with addition of α-hemolysin but not endotoxin. These results show that the permeability of porcine vagina ex-vivo to labeled toxin or water can be used to evaluate changes to the vaginal environment and modifications in tampon materials, and thus aid in risk assessment. - Highlights: • Model assessed local effects of tampon use on vaginal mucosa. • Risks were evaluated using two tracers to assess permeability in an ex vivo model. • Mechanical damage to the epithelial surface increased tracer penetration.

  4. 2011 NATA - Air Toxics Monitors

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset includes annual (2005 - 2013) statistics of measured ambient air toxics concentrations (in micrograms per cubic meter) and associated risk estimates for...

  5. Distributed Structure-Searchable Toxicity Database Network

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Distributed Structure-Searchable Toxicity (DSSTox) Database Network provides a public forum for search and publishing downloadable, structure-searchable,...

  6. Separations chemistry of toxic metals

    Energy Technology Data Exchange (ETDEWEB)

    Smith, P.; Barr, M.; Barrans, R. [and others

    1996-04-01

    Sequestering and removing toxic metal ions from their surroundings is an increasingly active area of research and is gaining importance in light of current environmental contamination problems both within the DOE complex and externally. One method of separating metal ions is to complex them to a molecule (a ligand or chelator) which exhibits specific binding affinity for a toxic metal, even in the presence of other more benign metals. This approach makes use of the sometimes subtle differences between toxic and non-toxic metals resulting from variations in size, charge and shape. For example, toxic metals such as chromium, arsenic, and technetium exist in the environment as oxyanions, negatively charged species with a characteristic tetrahedral shape. Other toxic metals such as actinides and heavy metals are positively charged spheres with specific affinities for particular donor atoms such as oxygen (for actinides) and nitrogen (for heavy metals). In most cases the toxic metals are found in the presence of much larger quantities of less toxic metals such as sodium, calcium and iron. The selectivity of the chelators is critical to the goal of removing the toxic metals from their less toxic counterparts. The approach was to build a ligand framework that complements the unique characteristics of the toxic metal (size, charge and shape) while minimizing interactions with non-toxic metals. The authors have designed ligands exhibiting specificity for the target metals; they have synthesized, characterized and tested these ligands; and they have shown that they exhibit the proposed selectivity and cooperative binding effects.

  7. Alterations in energy/redox metabolism induced by mitochondrial and environmental toxins: a specific role for glucose-6-phosphate-dehydrogenase and the pentose phosphate pathway in paraquat toxicity.

    Science.gov (United States)

    Lei, Shulei; Zavala-Flores, Laura; Garcia-Garcia, Aracely; Nandakumar, Renu; Huang, Yuting; Madayiputhiya, Nandakumar; Stanton, Robert C; Dodds, Eric D; Powers, Robert; Franco, Rodrigo

    2014-09-19

    Parkinson's disease (PD) is a multifactorial disorder with a complex etiology including genetic risk factors, environmental exposures, and aging. While energy failure and oxidative stress have largely been associated with the loss of dopaminergic cells in PD and the toxicity induced by mitochondrial/environmental toxins, very little is known regarding the alterations in energy metabolism associated with mitochondrial dysfunction and their causative role in cell death progression. In this study, we investigated the alterations in the energy/redox-metabolome in dopaminergic cells exposed to environmental/mitochondrial toxins (paraquat, rotenone, 1-methyl-4-phenylpyridinium [MPP+], and 6-hydroxydopamine [6-OHDA]) in order to identify common and/or different mechanisms of toxicity. A combined metabolomics approach using nuclear magnetic resonance (NMR) and direct-infusion electrospray ionization mass spectrometry (DI-ESI-MS) was used to identify unique metabolic profile changes in response to these neurotoxins. Paraquat exposure induced the most profound alterations in the pentose phosphate pathway (PPP) metabolome. 13C-glucose flux analysis corroborated that PPP metabolites such as glucose-6-phosphate, fructose-6-phosphate, glucono-1,5-lactone, and erythrose-4-phosphate were increased by paraquat treatment, which was paralleled by inhibition of glycolysis and the TCA cycle. Proteomic analysis also found an increase in the expression of glucose-6-phosphate dehydrogenase (G6PD), which supplies reducing equivalents by regenerating nicotinamide adenine dinucleotide phosphate (NADPH) levels. Overexpression of G6PD selectively increased paraquat toxicity, while its inhibition with 6-aminonicotinamide inhibited paraquat-induced oxidative stress and cell death. These results suggest that paraquat "hijacks" the PPP to increase NADPH reducing equivalents and stimulate paraquat redox cycling, oxidative stress, and cell death. Our study clearly demonstrates that alterations in

  8. Real-time environmental monitoring system: drilling campaign BM-CAL-4 Block, Camanu-Almada Basin, Bahia, Brazil; Sistema de monitoramento ambiental em tempo-real: Bloco BM-CAL-4, Bacia de Camamu-Almada, Bahia, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Pedro [El Paso Oleo e Gas, Natal, RN (Brazil); Cabral, Alexandre P. [Fugro OceansatPeg (Brazil)

    2008-07-01

    Between February and November 2007, the El Paso Oleo e Gas do Brasil Ltda. carried out a second exploratory campaign at the BM-CAL-4 Block (Camamu-Almada Basin), installing a real-time transmission metocean data monitoring system. Two metocean Wavescan (WS) buoys from Fugro were installed, transmitting current, wave and wind data to the El Paso crises room. The WS1 was positioned near the oil (10,5 km from the shore, at 22m depth), and the WS2 was located near the entrance of Barra Grande area (4,w km from the coast, at 10m depth). The real rime data fed the mathematical simulation using an oil spill model from Fugro Oceansatpeg. The metocean data Real-Time Environmental Monitoring System proved to be an important tool in the environmental management of the drilling activity located near the coastline. The sampling and real-time transmission of the current, wind and wave data allowed a better decision making regarding the selection of the best response strategies, saving time and resources in the simulation exercises, a vital issue in case of a real oil spill accident. (author)

  9. Block Cipher Analysis

    DEFF Research Database (Denmark)

    Miolane, Charlotte Vikkelsø

    Block ciphersarecryptographicprimitivesthatoperateon fixed sizetexts(blocks). Mostdesigns aim towards secure andfastencryption oflarge amounts ofdata. Block ciphers also serve as the building block of a number of hash functions and message authentication codes(MAC).Thetask of cryptanalysisisto en...... on small scale variants of AES. In the final part of the thesis we present a new block cipher proposal Present and examine its security against algebraic and differential cryptanalysis in particular.......Block ciphersarecryptographicprimitivesthatoperateon fixed sizetexts(blocks). Mostdesigns aim towards secure andfastencryption oflarge amounts ofdata. Block ciphers also serve as the building block of a number of hash functions and message authentication codes(MAC).Thetask of cryptanalysisisto...... ensurethat no attack violatesthe securitybounds specifiedbygeneric attack namely exhaustivekey search and table lookup attacks. This thesis contains a general introduction to cryptography with focus on block ciphers and important block cipher designs, in particular the Advanced Encryption Standard...

  10. 2nd European Meeting on Environmental Chemistry

    OpenAIRE

    Lichtfouse, Eric; Elbisser, Brigitte

    2001-01-01

    International audience; ORAL SESSIONS: AIR POLLUTION - ORGANIC POLLUTANTS, WATER AND FOOD POLLUTION - ORGANIC POLLUTANTS, SOIL POLLUTION - TOXIC METALS, ANALYTICAL METHODS FOR ENVIRONMENTAL SCIENCE, GREEN CHEMISTRY, ECOTOXICOLOGY, STABLE ISOTOPES FOR ENVIRONMENTAL SCIENCE, WATER POLLUTION - TOXIC METALS, ANALYTICAL METHODS FOR ENVIRONMENTAL SCIENCE, SOIL POLLUTION - ORGANIC POLLUTANTSPOSTER SESSIONS: AIR POLLUTION - TOXIC METALS, AIR POLLUTION - ORGANIC POLLUTANTS, WATER POLLUTION - TOXIC MET...

  11. Toxic Elements

    DEFF Research Database (Denmark)

    Hajeb, Parvaneh; Shakibazadeh, Shahram; Sloth, Jens Jørgen

    2016-01-01

    Food is considered the main source of toxic element (arsenic, cadmium, lead, and mercury) exposure to humans, and they can cause major public health effects. In this chapter, we discuss the most important sources for toxic element in food and the foodstuffs which are significant contributors to h...

  12. Tungsten toxicity.

    Science.gov (United States)

    Witten, Mark L; Sheppard, Paul R; Witten, Brandon L

    2012-04-05

    There is emerging evidence that tungsten has toxic health effects. We summarize the recent tungsten toxicity research in this short review. Tungsten is widely used in many commercial and military applications because it has the second highest melting temperature of any element. Consequently, it is important to elucidate the potential health effects of tungsten.

  13. Static renewal tests using Anodonta imbecillis (freshwater mussels). Anodonta imbecillis copper sulfate reference toxicant/food test, Clinch River-Environmental Restoration Program (CR-ERP)

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.J.

    1993-12-31

    Reference toxicant testing using juvenile freshwater mussels was conducted as part of the CR-ERP biomonitoring study of Clinch River sediments to assess the sensitivity of test organisms and the overall performance of the test. Tests were conducted using moderately hard synthetic water spiked with known concentrations of copper as copper sulfate. Two different foods, phytoplankton and YCT-Selenastrum (YCT-S), were tested in side by side tests to compare food quality. Toxicity testing of copper sulfate reference toxicant was conducted from July 6--15, 1993. The organisms used for testing were juvenile fresh-water mussels (Anodonta imbecillis). Although significant reduction in growth, compared to the phytoplankton control, was seen in all treatments, including the YCT-S Control, the consequence of this observation has not been established. Ninety-day testing of juvenile mussels exhibited large variations in growth within treatment and replicate groups. Attachments to this report include: Toxicity test bench sheets and statistical analyses; and Copper analysis request and results.

  14. Phosphatidylcholine Specific PLC-Induced Dysregulation of Gap Junctions, a Robust Cellular Response to Environmental Toxicants, and Prevention by Resveratrol in a Rat Liver Cell Model.

    Directory of Open Access Journals (Sweden)

    Iva Sovadinova

    Full Text Available Dysregulation of gap junctional intercellular communication (GJIC has been associated with different pathologies, including cancer; however, molecular mechanisms regulating GJIC are not fully understood. Mitogen Activated Protein Kinase (MAPK-dependent mechanisms of GJIC-dysregulation have been well-established, however recent discoveries have implicated phosphatidylcholine-specific phospholipase C (PC-PLC in the regulation of GJIC. What is not known is how prevalent these two signaling mechanisms are in toxicant/toxin-induced dysregulation of GJIC, and do toxicants/toxins work through either signaling mechanisms or both, or through alternative signaling mechanisms. Different chemical toxicants were used to assess whether they dysregulate GJIC via MEK or PC-PLC, or both Mek and PC-PLC, or through other signaling pathways, using a pluripotent rat liver epithelial oval-cell line, WB-F344. Epidermal growth factor, 12-O-tetradecanoylphorbol-13-acetate, thrombin receptor activating peptide-6 and lindane regulated GJIC through a MEK1/2-dependent mechanism that was independent of PC-PLC; whereas PAHs, DDT, PCB 153, dicumylperoxide and perfluorodecanoic acid inhibited GJIC through PC-PLC independent of Mek. Dysregulation of GJIC by perfluorooctanoic acid and R59022 required both MEK1/2 and PC-PLC; while benzoylperoxide, arachidonic acid, 18β-glycyrrhetinic acid, perfluorooctane sulfonic acid, 1-monolaurin, pentachlorophenol and alachlor required neither MEK1/2 nor PC-PLC. Resveratrol prevented dysregulation of GJIC by toxicants that acted either through MEK1/2 or PC-PLC. Except for alachlor, resveratrol did not prevent dysregulation of GJIC by toxicants that worked through PC-PLC-independent and MEK1/2-independent pathways, which indicated at least two other, yet unidentified, pathways that are involved in the regulation of GJIC.the dysregulation of GJIC is a contributing factor to the cancer process; however the underlying mechanisms by which gap

  15. Assessment by Ames test and comet assay of toxicity potential of polymer used to develop field-capable rapid-detection device to analyze environmental samples

    Science.gov (United States)

    Hebert, Amanda; Bishop, Michelle; Bhattacharyya, Dhiman; Gleason, Karen; Torosian, Stephen

    2015-08-01

    There is need for devices that decrease detection time of food-borne pathogens from days to real-time. In this study, a rapid-detection device is being developed and assessed for potential cytotoxicity. The device is comprised of melt-spun polypropylene coupons coated via oxidative chemical vapor deposition (oCVD) with 3,4-Ethylenedioxythiophene (EDOT), for conductivity and 3-Thiopheneethanol (3TE), allowing antibody attachment. The Ames test and comet assay have been used in this study to examine the toxicity potentials of EDOT, 3TE, and polymerized EDOT-co-3TE. For this study, Salmonella typhimurium strain TA1535 was used to assess the mutagenic potential of EDOT, 3TE and the copolymer. The average mutagenic potential of EDOT, 3TE and copolymer was calculated to be 0.86, 0.56, and 0.92, respectively. For mutagenic potential, on a scale from 0 to 1, close to 1 indicates low potential for toxicity, whereas a value of 0 indicates a high potential for toxicity. The comet assay is a single-cell gel electrophoresis technique that is widely used for this purpose. This assay measures toxicity based on the area or intensity of the comet-like shape that DNA fragments produce when DNA damage has occurred. Three cell lines were assessed; FRhK-4, BHK-21, and Vero cells. After averaging the results of all three strains, the tail intensity of the copolymer was 8.8 % and tail moment was 3.0, and is most similar to the untreated control, with average tail intensity of 5.7 % and tail moment of 1.7. The assays conducted in this study provide evidence that the copolymer is non-toxic to humans.

  16. EnviroAtlas - Phoenix, AZ - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset presents environmental benefits of the urban forest in 2,434 block groups in Phoenix, Arizona. Carbon attributes, pollution removal and value, and...

  17. EnviroAtlas - Pittsburgh, PA - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 1,089 block groups in Pittsburgh, Pennsylvania. Carbon attributes, temperature...

  18. EnviroAtlas - Memphis, TN - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 703 block groups in Memphis, Tennessee. Carbon attributes, temperature reduction,...

  19. EnviroAtlas - Cleveland, OH - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 1,442 block groups in Cleveland, Ohio. Carbon attributes, temperature reduction,...

  20. EnviroAtlas - Woodbine, IA - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 1 block group in Woodbine, Iowa. Carbon attributes, temperature reduction, pollution...

  1. EnviroAtlas - Portland, OR - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 1176 block groups in Portland, Oregon. Carbon attributes, temperature reduction,...

  2. EnviroAtlas - Milwaukee, WI - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 1,175 block groups in Milwaukee, Wisconsin. Carbon attributes, temperature reduction,...

  3. EnviroAtlas - Fresno, CA - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 405 block groups in Fresno, California. Carbon attributes, temperature reduction,...

  4. EnviroAtlas - Austin, TX - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 750 block groups in Austin, Texas. Carbon attributes, temperature reduction,...

  5. EnviroAtlas - Tampa, FL - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 1,833 block groups in Tampa Bay, Florida. Carbon attributes, temperature reduction,...

  6. EnviroAtlas - Portland, ME - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 146 block groups in Portland, Maine. Carbon attributes, temperature reduction,...

  7. EnviroAtlas - Paterson, NJ - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 107 block groups in Paterson, New Jersey. Carbon attributes, temperature reduction,...

  8. EnviroAtlas - Durham, NC - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 193 block groups in Durham, North Carolina. Carbon attributes, temperature reduction,...

  9. Toxicity and Safety Evaluation of Dufulin 30% WP to the Environmental Biology%30%毒氟磷可湿性粉剂对环境生物的毒性与安全性评价

    Institute of Scientific and Technical Information of China (English)

    范会涛; 李向阳; 陈卓; 宋宝安; 杨松; 胡德禹; 薛伟

    2011-01-01

    [目的]为顺利实现30%毒氟磷可湿性粉剂在今后农业生产中的广泛推广,参照的规定,进行了30%毒氟磷可湿性粉剂对环境有益生物鱼、蜂、鸟、蚕的急性毒性测定,并对其进行环境安全性评价.[结果]30%毒氟磷可湿性粉剂对鱼96 h的LC50值为12.4 mg/L,对蜂48 h的LC50>5000 mg/L,对鸟7 d的LD50>450 mg/kg体质量,对2龄家蚕胃杀毒性LC50>5000 mg/kg桑叶.[结论]30%毒氟磷可湿性粉剂对鱼类、蜂类、鸟类、家蚕均为低毒,实际风险为零.%[Aims] For the smooth realization of Dufulin 30% WP in the future to promote a wide range of agricultural production, reference to "environmental safety evaluation tests of chemical pesticides standards" requirement, the acute toxicity assay about environmental biology contained fish, bees, birds, silkworms against Dufulin 30% WP was completed, and environmental safety evaluation of Dufulin 30% WP was completed. [Results] It was shown LC· Value with 12.4 mg/L, more than 5000 mg/L, more than 450 mg/kg body weight and 5000 mg/kg for above tested objects at the treatment time of 96 h, 48 h, 7 d, 2nd instar larvae for differential objects, respectively. [Conclusions] The results indicated that Dufulin 30% WP belongs to low toxicity to environmental biology and without actual risks.

  10. Evaluation of mentum deformities of Chironomus spp. (Chironomidae: Diptera) larvae using modified toxic score index (MTSI) to assess the environmental stress in Juru River Basin, Penang, Malaysia.

    Science.gov (United States)

    Al-Shami, Salman Abdo; Salmah, Mad Rawi Che; Hassan, Ahmad Abu; Azizah, Mohd Nor Siti

    2011-06-01

    Morphological mentum deformities which represent sublethal effect of exposure to different types of pollutants were evaluated in Chironomus spp. larvae inhabiting three polluted rivers of Juru River Basin in northwestern peninsular Malaysia. Using mentum deformity incidences, the modified toxic score index (MTSI) was developed based on Lenat's toxic score index (TSI). The suggested MTSI was compared with TSI in terms of its effectiveness to identify different pollutants including heavy metals. The MTSI showed stronger relationship to total deformity incidence expressed as percentage. Additionally, the multivariate RDA model showed higher capability of MTSI to explain the variations in heavy metal contents of the river sediments. The MTSI was recommended in bioassessment of water and sediment quality using the mentum deformities of Chironomus spp. larvae from aquatic ecosystems receiving anthropogenic, agricultural, or industrial discharges.

  11. Environmental consequences of the inhibition in the hatching of pupae of Aedes aegypti by mercury, zinc, and chromium - the abnormal toxicity of zinc

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, S.A.; Nipaney, P.C.; Soni, R.

    1985-01-01

    In continuation of our studies on the toxicity of heavy metals the authors report the impact of mercury (II), zinc (II), and chromium (VI) on hatching of the pupae of mosquito Aedes aegypti. The studies were carried out in terms of abnormal responses in swimming and flying, incompleteness of the metamorphosis and mortality - all with respect to controls. The toxicity trend with respect to the mortality of pupae in partially or completely hatched conditions, as also with respect to reduction in the number of pupae reaching the mosquito stage was Hg > Zn approx. = Cr. A comparison of lethal doze values of the metals obtained through present experiments with the levels allowable in irrigation waters, indicate that the permissible levels of zinc and chromium are higher by several orders of magnitude than the lowest lethal concentrations for pupae of A. aegypti. The studies thus point to a need for the revision of the existing standards.

  12. Toxicity of Ag, CuO and ZnO nanoparticles to selected environmentally relevant test organisms and mammalian cells in vitro: a critical review.

    Science.gov (United States)

    Bondarenko, Olesja; Juganson, Katre; Ivask, Angela; Kasemets, Kaja; Mortimer, Monika; Kahru, Anne

    2013-07-01

    Nanoparticles (NPs) of copper oxide (CuO), zinc oxide (ZnO) and especially nanosilver are intentionally used to fight the undesirable growth of bacteria, fungi and algae. Release of these NPs from consumer and household products into waste streams and further into the environment may, however, pose threat to the 'non-target' organisms, such as natural microbes and aquatic organisms. This review summarizes the recent research on (eco)toxicity of silver (Ag), CuO and ZnO NPs. Organism-wise it focuses on key test species used for the analysis of ecotoxicological hazard. For comparison, the toxic effects of studied NPs toward mammalian cells in vitro were addressed. Altogether 317 L(E)C50 or minimal inhibitory concentrations (MIC) values were obtained for algae, crustaceans, fish, bacteria, yeast, nematodes, protozoa and mammalian cell lines. As a rule, crustaceans, algae and fish proved most sensitive to the studied NPs. The median L(E)C50 values of Ag NPs, CuO NPs and ZnO NPs (mg/L) were 0.01, 2.1 and 2.3 for crustaceans; 0.36, 2.8 and 0.08 for algae; and 1.36, 100 and 3.0 for fish, respectively. Surprisingly, the NPs were less toxic to bacteria than to aquatic organisms: the median MIC values for bacteria were 7.1, 200 and 500 mg/L for Ag, CuO and ZnO NPs, respectively. In comparison, the respective median L(E)C50 values for mammalian cells were 11.3, 25 and 43 mg/L. Thus, the toxic range of all the three metal-containing NPs to target- and non-target organisms overlaps, indicating that the leaching of biocidal NPs from consumer products should be addressed.

  13. Total Spinal Block after Thoracic Paravertebral Block.

    Science.gov (United States)

    Beyaz, Serbülent Gökhan; Özocak, Hande; Ergönenç, Tolga; Erdem, Ali Fuat; Palabıyık, Onur

    2014-02-01

    Thoracic paravertebral block (TPVB) can be performed with or without general anaesthesia for various surgical procedures. TPVB is a popular anaesthetic technique due to its low side effect profile and high analgesic potency. We used 20 mL of 0.5% levobupivacaine for a single injection of unilateral TPVB at the T7 level with neurostimulator in a 63 year old patient with co-morbid disease who underwent cholecystectomy. Following the application patient lost consciousness, and was intubated. Haemodynamic instability was normalised with rapid volume replacement and vasopressors. Anaesthetic drugs were stopped at the end of the surgery and muscle relaxant was antagonised. Return of mucle strenght was shown with neuromuscular block monitoring. Approximately three hours after TPVB, spontaneous breathing started and consciousness returned. A total spinal block is a rare and life-threatening complication. A total spinal block is a complication of spinal anaesthesia, and it can also occur after peripheral blocks. Clinical presentation is characterised by hypotension, bradicardia, apnea, and cardiac arrest. An early diagnosis and appropriate treatment is life saving. In this case report, we want to present total spinal block after TPVB.

  14. Generalized Block Failure

    DEFF Research Database (Denmark)

    Jönsson, Jeppe

    2015-01-01

    Block tearing is considered in several codes as a pure block tension or a pure block shear failure mechanism. However in many situations the load acts eccentrically and involves the transfer of a substantial moment in combination with the shear force and perhaps a normal force. A literature study...... yield lines around the block leads to simple interaction formulas similar to other interaction formulas in the codes.......Block tearing is considered in several codes as a pure block tension or a pure block shear failure mechanism. However in many situations the load acts eccentrically and involves the transfer of a substantial moment in combination with the shear force and perhaps a normal force. A literature study...

  15. Human Toxicity

    DEFF Research Database (Denmark)

    Jolliet, Olivier; Fantke, Peter

    2015-01-01

    . The first section of this chapter outlines the complete cause-effect pathway, from emissions of toxic substances to intake by the population up to damages in terms of human health effects. Section 2 outlines the framework for assessing human toxicity in LCIA. Section 3 discusses the contributing substances......This chapter reviews the human toxicological impacts of chemicals and how to assess these impacts in life cycle impact assessment (LCIA), in order to identify key processes and pollutants. The complete cause-effect pathway – from emissions of toxic substances up to damages on human health...... – demonstrates the importance to account for both outdoor and indoor exposure, including consumer products. Analysing the variations in intake fraction (the fraction of the emitted or applied chemical that is taken in by the consumer and the general population), effect factor and characterisation factor across...

  16. Dioxin exposure blocks lactation through a direct effect on mammary epithelial cells mediated by the aryl hydrocarbon receptor repressor.

    Science.gov (United States)

    Basham, Kaitlin J; Leonard, Christopher J; Kieffer, Collin; Shelton, Dawne N; McDowell, Maria E; Bhonde, Vasudev R; Looper, Ryan E; Welm, Bryan E

    2015-01-01

    In mammals, lactation is a rich source of nutrients and antibodies for newborn animals. However, millions of mothers each year experience an inability to breastfeed. Exposure to several environmental toxicants, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), has been strongly implicated in impaired mammary differentiation and lactation. TCDD and related polyhalogenated aromatic hydrocarbons are widespread industrial pollutants that activate the aryl hydrocarbon receptor (AHR). Despite many epidemiological and animal studies, the molecular mechanism through which AHR signaling blocks lactation remains unclear. We employed in vitro models of mammary differentiation to recapitulate lactogenesis in the presence of toxicants. We demonstrate AHR agonists directly block milk production in isolated mammary epithelial cells. Moreover, we define a novel role for the aryl hydrocarbon receptor repressor (AHRR) in mediating this response. Our mechanistic studies suggest AHRR is sufficient to block transcription of the milk gene β-casein. As TCDD is a prevalent environmental pollutant that affects women worldwide, our results have important public health implications for newborn nutrition.

  17. Toxic myopathies.

    Science.gov (United States)

    Pasnoor, Mamatha; Barohn, Richard J; Dimachkie, Mazen M

    2014-08-01

    Muscle tissue is highly sensitive to many substances. Early recognition of toxic myopathies is important, because they potentially are reversible on removal of the offending drug or toxin, with greater likelihood of complete resolution the sooner this is achieved. Clinical features range from mild muscle pain and cramps to severe weakness with rhabdomyolysis, renal failure, and even death. The pathogenic bases can be multifactorial. This article reviews some of the common toxic myopathies and their clinical presentation, histopathologic features, and possible underlying cellular mechanisms.

  18. BLOCK H-MATRICES AND SPECTRUM OF BLOCK MATRICES

    Institute of Scientific and Technical Information of China (English)

    黄廷祝; 黎稳

    2002-01-01

    The block H-matrices are studied by the concept of G-functions, several concepts of block matrices are introduced. Equivalent characters of block H-matrices are obtained. Spectrum localizations claracterized by Gfunctions for block matrices are got.

  19. Predicting refinery effluent toxicity on the basis of hydrocarbon composition determined by GCxGC analysis

    Energy Technology Data Exchange (ETDEWEB)

    Whale, G. [and others

    2013-04-15

    A high resolution analytical method for determining hydrocarbon blocks in petroleum products by comprehensive two-dimensional gas chromatography (GCxGC) was used for the analysis of petroleum hydrocarbons extracted from refinery effluents. From 105 CONCAWE refineries in Europe 111 refinery effluents were collected in the period June 2008 to March 2009 (CONCAWE, 2010). The effluents were analysed for metals, standard effluent parameters (including Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), oil in water (OiW), GCxGC speciated hydrocarbons, BTEX (Benzene, Toluene, Ethylbenzene, and Xylenes) and volatile organic compounds. This report describes the subsequent analysis of the GCxGC data, as described in hydrocarbon blocks, and uses the PETROTOX model, to predict the environmental toxicity (i.e. ecotoxicity) of the discharged effluents. A further analysis was undertaken to address the potential environmental impact of these predicted effects initially using default dilution factors and then,when necessary site specific factors. The report describes all the methods used to arrive at the predictions, and shows that for the majority of refinery effluents direct toxicity effects in the effluents are not anticipated. Furthermore, when applying either the EU Risk Assessment Technical Guidance Document (TGD) default dilution factors or site specific dilution factors, none of the refineries are predicted to exerting either acute or chronic toxicity to organisms in the receiving aquatic environment, based on their hydrocarbon composition present in the effluent samples.

  20. Block TERM factorization of block matrices

    Institute of Scientific and Technical Information of China (English)

    SHE Yiyuan; HAO Pengwei

    2004-01-01

    Reversible integer mapping (or integer transform) is a useful way to realize Iossless coding, and this technique has been used for multi-component image compression in the new international image compression standard JPEG 2000. For any nonsingular linear transform of finite dimension, its integer transform can be implemented by factorizing the transform matrix into 3 triangular elementary reversible matrices (TERMs) or a series of single-row elementary reversible matrices (SERMs). To speed up and parallelize integer transforms, we study block TERM and SERM factorizations in this paper. First, to guarantee flexible scaling manners, the classical determinant (det) is generalized to a matrix function, DET, which is shown to have many important properties analogous to those of det. Then based on DET, a generic block TERM factorization,BLUS, is presented for any nonsingular block matrix. Our conclusions can cover the early optimal point factorizations and provide an efficient way to implement integer transforms for large matrices.

  1. Lesson Thirteen Trifascicular Block

    Institute of Scientific and Technical Information of China (English)

    鲁端; 王劲

    2005-01-01

    @@ A complete trifascicular block would result in complete AV block. The idio ventricular rhythm has a slower rate and a wide QRS complex because the pacemaker is located at the peripheral part of the conduction system distal to the sites of the block1. Such a rhythm may be difficult to differentiate from bifascicular or bundle branch block combined with complete block at a higher level such as the AV node or His bundle2. Besides a slower ventricular rate, a change in the morphology of the QRS complex from a previous known bifascicular pattern would be strongly suggestive of a trifascicular origin of the complete AV block3. A His bundle recording is required for a definitive diagnosis, however.

  2. Review of Systems Biology Approach to Study on Developmental Toxicity Mechanism of Environmental Pollutants%环境污染物发育毒性机制研究的系统生物学方法进展

    Institute of Scientific and Technical Information of China (English)

    徐挺; 赵静; 胡霞林; 尹大强

    2011-01-01

    基因调控网络(gene regulatory network,GRN)是用于研究基因调控的一种新兴的系统生物学方法,尤其适合描述生物体早期发育的调控系统和机制.由于它能体现出调控过程的网络特性和动态关系,从整体的角度全面审视环境扰动所造成的真实影响,因此有望在内分泌干扰物等环境污染物的发育毒性机制研究中发挥重要作用,解决多年来一直困扰相关研究的种种难题.针对基因调控网络的结构、研究方法、应用成果和案例进行综述,并对将这一方法应用于污染物发育毒性机制研究的前景做出展望.%Gene regulatory network (GRN) was a novel systematical biology approach for the study on gene regulation mechanism, especially helpful in describing the early development of animal body. Because GRNs can present the networks and dynamics of regulatory processing and the true impacts from the environmental perturbation, they were expected to play a key role in studying developmental toxicity mechanisms of environmental pollutants including endocrine disrupting chemicals with resolving many problems which existed for a long time. The structures, methodologies, current application cases of GRNs are rewiewed. The application of GRNs into mechanism researches of developmental toxicity of pollutants is previewed in this paper.

  3. (Environmental technology)

    Energy Technology Data Exchange (ETDEWEB)

    Boston, H.L.

    1990-10-12

    The traveler participated in a conference on environmental technology in Paris, sponsored by the US Embassy-Paris, US Environmental Protection Agency (EPA), the French Environmental Ministry, and others. The traveler sat on a panel for environmental aspects of energy technology and made a presentation on the potential contributions of Oak Ridge National Laboratory (ORNL) to a planned French-American Environmental Technologies Institute in Chattanooga, Tennessee, and Evry, France. This institute would provide opportunities for international cooperation on environmental issues and technology transfer related to environmental protection, monitoring, and restoration at US Department of Energy (DOE) facilities. The traveler also attended the Fourth International Conference on Environmental Contamination in Barcelona. Conference topics included environmental chemistry, land disposal of wastes, treatment of toxic wastes, micropollutants, trace organics, artificial radionuclides in the environment, and the use biomonitoring and biosystems for environmental assessment. The traveler presented a paper on The Fate of Radionuclides in Sewage Sludge Applied to Land.'' Those findings corresponded well with results from studies addressing the fate of fallout radionuclides from the Chernobyl nuclear accident. There was an exchange of new information on a number of topics of interest to DOE waste management and environmental restoration needs.

  4. Blocked Urethral Valves

    Science.gov (United States)

    ... Blocked Urethral Valves Health Issues Listen Español Text Size Email Print Share Blocked Urethral Valves Page Content Article Body Urine leaves the bladder through a tube called the urethra, which in boys passes through the penis. Rarely, small membranes form across the urethra in ...

  5. Types of Heart Block

    Science.gov (United States)

    ... P wave as it normally would. If an electrical signal is blocked before it reaches the ventricles, they won't contract and pump blood to the lungs and the rest of the body. Second-degree heart block is divided into two ...

  6. Related Drupal Nodes Block

    NARCIS (Netherlands)

    Van der Vegt, Wim

    2010-01-01

    Related Drupal Nodes Block This module exposes a block that uses Latent Semantic Analysis (Lsa) internally to suggest three nodes that are relevant to the node a user is viewing. This module performs three tasks. 1) It periodically indexes a Drupal site and generates a Lsa Term Document Matrix. Inde

  7. The Block Neighborhood

    CERN Document Server

    Arrighi, Pablo

    2010-01-01

    We define the block neighborhood of a reversible CA, which is related both to its decomposition into a product of block permutations and to quantum computing. We give a purely combinatorial characterization of the block neighborhood, which helps in two ways. First, it makes the computation of the block neighborhood of a given CA relatively easy. Second, it allows us to derive upper bounds on the block neighborhood: for a single CA as function of the classical and inverse neighborhoods, and for the composition of several CAs. One consequence of that is a characterization of a class of "elementary" CAs that cannot be written as the composition of two simpler parts whose neighborhoods and inverse neighborhoods would be reduced by one half.

  8. Betaine-based heat transfer fluids as a natural solution for environmental, toxic and corrosion problems in heating and cooling systems; Betaine gebaseerde koudedragers als natuurlijke oplossing voor milieu-, toxiciteit- en corrosieproblemen in verwarming- en koelsystemen

    Energy Technology Data Exchange (ETDEWEB)

    Jokinen, J. [Fortum Oil and Gas Oy, Porvoo (Finland); Willems, B.P.M. [Marketing and Technology Consult, Rijen (Netherlands)

    2005-02-01

    The reason for the study on the title subject was the environmental risk and toxicity of many conventional heat transfer fluids like glycols. Fluid toxicity and environmental risk in building systems and industrial use is becoming less acceptable. Alternative fluids have been sought from among salt solutions and vegetable oils. Still, those alternative materials are not very attractive. Main technical problems have been high viscosity and corrosion. A new possible alternative, a betaine-water solution was tested and developed for heat transfer purposes. Betaine (trimethyl glycine) is a by-product of the sugar industry. Therefore, betaine is completely non-toxic and also not harmful to the environment. Betaine is a renowned substance in the pharmaceutical, cosmetic, food and medical industry. Adequate freezing protection is achieved with betaine concentration of 20-55% by weight. This solution was found to have other good qualities also; it has good heat transfer abilities, is not harmful to materials used in systems and has natural corrosion protection properties. The development work consisted of carefully measuring freeze protection and pipe burst protection with different betaine concentrations, measuring physical properties in the same circumstances and developing the additive package for enhanced corrosion protection. Field-testing was carried out for four years. Testing showed that a betaine-water solution has good thermodynamic properties to be used as a heat transfer fluid in the HVAC industry, with additional environmental-, non-toxic and corrosion properties. The concrete result was a trademark and patent protected new product for the industry. [Dutch] Warmteoverdracht wordt heden ten dage veelvuldig toegepast in zowel de industrie als in kantoren en gebouwen. Hoewel de warmteoverdrachttechnologie enorm is vooruitgegaan worden het potentieel en de voordelen van een zorgvuldig gekozen koudedrager vaak over het hoofd gezien. De selectie van de juiste

  9. Inflammatory and toxic myopathies.

    Science.gov (United States)

    Dalakas, M C

    1992-10-01

    The major advances in the immunopathogenesis and treatment of inflammatory myopathies, and the main criteria that distinguish polymyositis (PM) from dermatomyositis (DM) or inclusion-body myositis (IBM) are presented. The origin and implications of the amyloid and ubiquitin deposits found within the vacuolated fibers of patients with IBM are considered. The pathogenesis of human immunodeficiency virus (HIV) and human T-cell lymphotrophic virus (HTLV)-I-associated PM is presented, and the role of retroviruses in triggering PM, even in the absence of detectable viral genome within the muscle fibers, is discussed. In addition, three toxic myopathies with distinct morphologic, biochemical, or molecular characteristics, caused by zidovudine [azidothymidine (AZT) myopathy], the cholesterol-lowering-agent myopathy (CLAM), and the combination of blocking agents with corticosteroids are presented.

  10. Thermal Stress and Toxicity

    Science.gov (United States)

    Elevating ambient temperature above thermoneutrality exacerbates toxicity of most air pollutants, insecticides, and other toxic chemicals. On the other hand, safety and toxicity testing of toxicants and drugs is usually performed in mice and rats maintained at subthermoneutral te...

  11. Toxicity of TiO2 nanoparticles on soil nitrification at environmentally relevant concentrations: Lack of classical dose-response relationships.

    Science.gov (United States)

    Simonin, Marie; Martins, Jean M F; Le Roux, Xavier; Uzu, Gaëlle; Calas, Aude; Richaume, Agnès

    2017-03-01

    Titanium-dioxide nanoparticles (TiO2-NPs) are increasingly released in agricultural soils through, e.g. biosolids, irrigation or nanoagrochemicals. Soils are submitted to a wide range of concentrations of TiO2-NPs depending on the type of exposure. However, most studies have assessed the effects of unrealistically high concentrations, and the dose-response relationships are not well characterized for soil microbial communities. Here, using soil microcosms, we assessed the impact of TiO2-NPs at concentrations ranging from 0.05 to 500 mg kg(-1 )dry-soil, on the activity and abundance of ammonia-oxidizing archaea (AOA) and bacteria (AOB), and nitrite-oxidizing bacteria (Nitrobacter and Nitrospira). In addition, aggregation and oxidative potential of TiO2-NPs were measured in the spiking suspensions, as they can be important drivers of TiO2-NPs toxicity. After 90 days of exposure, non-classical dose-response relationships were observed for nitrifier abundance or activity, making threshold concentrations impossible to compute. Indeed, AOA abundance was reduced by 40% by TiO2-NPs whatever the concentration, while Nitrospira was never affected. Moreover, AOB and Nitrobacter abundances were decreased mainly at intermediate concentrations nitrification was reduced by 25% at the lowest (0.05 mg kg(-1)) and the highest (100 and 500 mg kg(-1)) TiO2-NPs concentrations. Path analyses indicated that TiO2-NPs affected nitrification through an effect on the specific activity of nitrifiers, in addition to indirect effects on nitrifier abundances. Altogether these results point out the need to include very low concentrations of NPs in soil toxicological studies, and the lack of relevance of classical dose-response tests and ecotoxicological dose metrics (EC50, IC50…) for TiO2-NPs impact on soil microorganisms.

  12. 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

    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......Background: In toxicological testing, effects of endocrine disrupters are in most cases more thoroughly investigated in males than in females. In males the hypothesis of testicu lar dysgenesis syndrome (TDS) proposes that there is a common origin in fetal life of the increase in frequency observed...... in later years of for example incidence of boys born with hypospadias and young men with low semen quality in the human male population. Furthermore, it has been observed in animal studies that exposure during fetal life to endocrine disrupters may lead to similar adverse reproductive effects. It has been...

  13. Anaerobic Toxicity of Cationic Silver Nanoparticles

    Data.gov (United States)

    U.S. Environmental Protection Agency — Toxicity data for the impact of nano-silver on anaerobic degradation. This dataset is associated with the following publication: Gitipour, A., S. Thiel, K. Scheckel,...

  14. 40 CFR 798.2250 - Dermal toxicity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Dermal toxicity. 798.2250 Section 798.2250 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... animals of each sex with healthy skin shall be used at each dose level. (B) The females shall...

  15. Block copolymer battery separator

    Science.gov (United States)

    Wong, David; Balsara, Nitash Pervez

    2016-04-26

    The invention herein described is the use of a block copolymer/homopolymer blend for creating nanoporous materials for transport applications. Specifically, this is demonstrated by using the block copolymer poly(styrene-block-ethylene-block-styrene) (SES) and blending it with homopolymer polystyrene (PS). After blending the polymers, a film is cast, and the film is submerged in tetrahydrofuran, which removes the PS. This creates a nanoporous polymer film, whereby the holes are lined with PS. Control of morphology of the system is achieved by manipulating the amount of PS added and the relative size of the PS added. The porous nature of these films was demonstrated by measuring the ionic conductivity in a traditional battery electrolyte, 1M LiPF.sub.6 in EC/DEC (1:1 v/v) using AC impedance spectroscopy and comparing these results to commercially available battery separators.

  16. Steroidal neuromuscular blocking agents

    NARCIS (Netherlands)

    Wierda, JMKH; Mori, K; Ohmura, A; Toyooka, H; Hatano, Y; Shingu, K; Fukuda, K

    1998-01-01

    Since 1964 approximately 20 steroidal neuromuscular blocking agents have been evaluated clinically. Pancuronium, a bisquaternary compound designed on the drawingboard, was the first steroidal relaxant introduced into clinical practice worldwide in the 1970's. Although a major improvement, pancuroniu

  17. Determination of estrogenic mycotoxins in environmental water samples by low-toxicity dispersive liquid-liquid microextraction and liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Emídio, Elissandro Soares; da Silva, Claudia Pereira; de Marchi, Mary Rosa Rodrigues

    2015-04-24

    A novel, simple, rapid and eco-friendly method based on dispersive liquid-liquid microextraction using a bromosolvent was developed to determine six estrogenic mycotoxins (zearalenone, zearalanone, α-zearalanol, β-zearalanol, α-zearalenol and β-zearalenol) in water samples by liquid chromatography-electrospray ionization tandem mass spectrometry in the negative mode (LC-ESI-MS/MS). The optimal conditions for this method include the use of 100 μL bromocyclohexane as an extraction solvent (using a non-dispersion solvent), 10 mL of aqueous sample (adjusted to pH 4), a vortex extraction time of 2 min, centrifugation for 10 min at 3500 rpm and no ionic strength adjustment. The calibration function was linear and was verified by applying the Mandel fitting test with a 95% confidence level. No matrix effect was observed. According to the relative standard deviations (RSDs), the precision was better than 13% for the repeatability and intermediate precision. The average recoveries of the spiked compounds ranged from 81 to 118%. The method limits of detection (LOD) and quantification (LOQ) considering a 125-fold pre-concentration step were 4-20 and 8-40 ng L(-1), respectively. Next, the method was applied to the analysis of the environmental aqueous samples, demonstrating the presence of β-zearalanol and zearalanone in the river water samples.

  18. Surviving in a toxic world: transcriptomics and gene expression profiling in response to environmental pollution in the critically endangered European eel

    Directory of Open Access Journals (Sweden)

    Pujolar Jose

    2012-09-01

    Full Text Available Abstract Background Genomic and transcriptomic approaches have the potential for unveiling the genome-wide response to environmental perturbations. The abundance of the catadromous European eel (Anguilla anguilla stock has been declining since the 1980s probably due to a combination of anthropogenic and climatic factors. In this paper, we explore the transcriptomic dynamics between individuals from high (river Tiber, Italy and low pollution (lake Bolsena, Italy environments, which were measured for 36 PCBs, several organochlorine pesticides and brominated flame retardants and nine metals. Results To this end, we first (i updated the European eel transcriptome using deep sequencing data with a total of 640,040 reads assembled into 44,896 contigs (Eeelbase release 2.0, and (ii developed a transcriptomic platform for global gene expression profiling in the critically endangered European eel of about 15,000 annotated contigs, which was applied to detect differentially expressed genes between polluted sites. Several detoxification genes related to metabolism of pollutants were upregulated in the highly polluted site, including genes that take part in phase I of the xenobiotic metabolism (CYP3A, phase II (glutathione-S-transferase and oxidative stress (glutathione peroxidase. In addition, key genes in the mitochondrial respiratory chain and oxidative phosphorylation were down-regulated at the Tiber site relative to the Bolsena site. Conclusions Together with the induced high expression of detoxification genes, the suggested lowered expression of genes supposedly involved in metabolism suggests that pollution may also be associated with decreased respiratory and energy production.

  19. Tartaric Acid as a Non-toxic and Environmentally-Friendly Anti-scaling Material for Using in Cooling Water Systems: Electrochemical and Surface Studies

    Science.gov (United States)

    Asghari, Elnaz; Gholizadeh-Khajeh, Maryam; Ashassi-Sorkhabi, Habib

    2016-10-01

    Because of the major limitations in drinking water resources, the industries need to use unprocessed water sources for their cooling systems; these water resources contain major amount of hardening cations. So, mineral scales are formed in cooling water systems during the time and cause major problems. The use of green anti-scaling materials such as carboxylic acids is considered due to their low risks of environmental pollution. In the present work, the scale inhibition performance of tartaric acid as a green organic material was evaluated. Chemical screening tests, cathodic and anodic voltammetry measurements and electrochemical impedance spectroscopy (EIS), field emission scanning electron microscopy (FESEM), energy-dispersive x-ray and x-ray diffraction, were used for the evaluation of the scale inhibition performance. The results showed that tartaric acid can prevent calcium carbonate precipitation significantly. The hard water solution with 2.0 mM of tartaric acid indicated the highest scale inhibition efficiency (ca. 68%). The voltammetry, EIS and FESEM results verified that tartaric acid can form smooth and homogeneous film on steel surface through formation of Fe(III)-tartrate complexes and retard the local precipitation of calcium carbonate deposits.

  20. Surviving in a toxic world: transcriptomics and gene expression profiling in response to environmental pollution in the critically endangered European eel

    Science.gov (United States)

    2012-01-01

    Background Genomic and transcriptomic approaches have the potential for unveiling the genome-wide response to environmental perturbations. The abundance of the catadromous European eel (Anguilla anguilla) stock has been declining since the 1980s probably due to a combination of anthropogenic and climatic factors. In this paper, we explore the transcriptomic dynamics between individuals from high (river Tiber, Italy) and low pollution (lake Bolsena, Italy) environments, which were measured for 36 PCBs, several organochlorine pesticides and brominated flame retardants and nine metals. Results To this end, we first (i) updated the European eel transcriptome using deep sequencing data with a total of 640,040 reads assembled into 44,896 contigs (Eeelbase release 2.0), and (ii) developed a transcriptomic platform for global gene expression profiling in the critically endangered European eel of about 15,000 annotated contigs, which was applied to detect differentially expressed genes between polluted sites. Several detoxification genes related to metabolism of pollutants were upregulated in the highly polluted site, including genes that take part in phase I of the xenobiotic metabolism (CYP3A), phase II (glutathione-S-transferase) and oxidative stress (glutathione peroxidase). In addition, key genes in the mitochondrial respiratory chain and oxidative phosphorylation were down-regulated at the Tiber site relative to the Bolsena site. Conclusions Together with the induced high expression of detoxification genes, the suggested lowered expression of genes supposedly involved in metabolism suggests that pollution may also be associated with decreased respiratory and energy production. PMID:23009661

  1. Environmental impact of toxic metals and metalloids from the Muñón Cimero mercury-mining area (Asturias, Spain).

    Science.gov (United States)

    Loredo, Jorge; Ordóñez, Almudena; Alvarez, Rodrigo

    2006-08-25

    This paper presents the results of the sampling surveys carried out in order to evaluate the environmental problems associated to La Soterraña, an abandoned Hg mine in Asturias, north of Spain. In particular, this paper overviews the impact of mining and metallurgical activities on terrestrial and aquatic environments. The wastes generated during the mining activity (ore extraction and processing) and later accumulated on the ground, contain great amount of sulphides, becoming potentially acid-generating. Consequently, the mobility of heavy metals and other ecotoxic elements is enhanced. Wastes are generally located close to watercourses and on very steep hillsides, where they are exposed to oxidative weathering, posing a significant risk due to the release of ecotoxic elements to the environment. Background levels were determined at sites, which had not been directly affected by mercury mining. A multielemental geochemical study of mining wastes, soils, stream sediments, water and air samples collected in the area of influence of the old mining and metallurgical works was carried out. Total Hg and As concentrations in soils reach values up to 502 and 19,940 mg kg(-1), respectively, 500 and 2000 times higher than the local background levels. The effects of mining seem to be intense both in waters and stream sediments, as well as in the local atmosphere, whose Hg content is 10 times higher than the background level in the area. Therefore, the target carcinogenic risk was exceeded for As and Hg in La Soterraña site.

  2. Environmental biochemistry of chromium.

    Science.gov (United States)

    Losi, M E; Amrhein, C; Frankenberger, W T

    1994-01-01

    Chromium is a d-block transitional element with many industrial uses. It occurs naturally in various crustal materials and is discharged to the environment as industrial waste. Although it can occur in a number of oxidation states, only 3+ and 6+ are found in environmental systems. The environmental behavior of Cr is largely a function of its oxidation state. Hexavalent Cr compounds (mainly chromates and dichromates) are considered toxic to a variety of terrestrial and aquatic organisms and are mobile in soil/water systems, much more so than trivalent Cr compounds. This is largely because of differing chemical properties: Hexavalent Cr compounds are strong oxidizers and highly soluble, while trivalent Cr compounds tend to form relatively inert precipitates at near-neutral pH. The trivalent state is generally considered to be the stable form in equilibrium with most soil/water systems. A diagram of the Cr cycle in soils and water is given in Fig. 6 (Bartlett 1991). This illustration provides a summary of environmentally relevant reactions. Beginning with hexavalent Cr that is released into the environment as industrial waste, there are a number of possible fates, including pollution of soil and surface water and leaching into groundwater, where it may remain stable and, in turn, can be taken up by plants or animals, and adsorption/precipitation, involving soil colloids and/or organic matter. Herein lies much of the environmental concern associated with the hexavalent form. A portion of the Cr(VI) will be reduced to the trivalent form by inorganic electron donors, such as Fe2+ and S2-, or by bioprocesses involving organic matter. Following this conversion, Cr3+ can be expected to precipitate as oxides and hydroxides or to form complexes with numerous ligands. This fraction includes a vast majority of global Cr reserves. Soluble Cr3+ complexes, such as those formed with citrate, can undergo oxidation when they come in contact with manganese dioxide, thus reforming

  3. EnviroAtlas - Cleveland, OH - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  4. EnviroAtlas - Paterson, NJ - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  5. EnviroAtlas - Tampa, FL - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of waterbodies. A potential...

  6. EnviroAtlas - Pittsburgh, PA - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  7. EnviroAtlas - New Bedford, MA - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  8. EnviroAtlas - Des Moines, IA - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  9. EnviroAtlas - New York, NY - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  10. EnviroAtlas - Milwaukee, WI - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  11. EnviroAtlas - Austin, TX - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  12. EnviroAtlas - Memphis, TN - Residents with Minimal Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  13. EnviroAtlas - Paterson, NJ - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  14. EnviroAtlas - Fresno, CA - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  15. EnviroAtlas - Portland, ME - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  16. EnviroAtlas - Portland, ME - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  17. EnviroAtlas - Fresno, CA - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  18. EnviroAtlas - Woodbine, IA - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  19. EnviroAtlas - Tampa, FL - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  20. EnviroAtlas - Durham, NC - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  1. EnviroAtlas - New Bedford, MA - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  2. EnviroAtlas - Pittsburgh, PA - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  3. EnviroAtlas - Minneapolis/St. Paul, MN - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  4. EnviroAtlas - Cleveland, OH - Residents with Minimal Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  5. EnviroAtlas - Green Bay, WI - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  6. EnviroAtlas - Green Bay, WI - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  7. EnviroAtlas - Milwaukee, WI - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  8. EnviroAtlas - Portland, OR - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  9. EnviroAtlas - Portland, OR - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  10. EnviroAtlas - Memphis, TN - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  11. EnviroAtlas - Austin, TX - Residents with Minimal Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  12. EnviroAtlas - Phoenix, AZ - Residents with Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  13. Molecular toxicity mechanism of nanosilver

    Directory of Open Access Journals (Sweden)

    Danielle McShan

    2014-03-01

    Full Text Available Silver is an ancient antibiotic that has found many new uses due to its unique properties on the nanoscale. Due to its presence in many consumer products, the toxicity of nanosilver has become a hot topic. This review summarizes recent advances, particularly the molecular mechanism of nanosilver toxicity. The surface of nanosilver can easily be oxidized by O2 and other molecules in the environmental and biological systems leading to the release of Ag+, a known toxic ion. Therefore, nanosilver toxicity is closely related to the release of Ag+. In fact, it is difficult to determine what portion of the toxicity is from the nano-form and what is from the ionic form. The surface oxidation rate is closely related to the nanosilver surface coating, coexisting molecules, especially thiol-containing compounds, lighting conditions, and the interaction of nanosilver with nucleic acids, lipid molecules, and proteins in a biological system. Nanosilver has been shown to penetrate the cell and become internalized. Thus, nanosilver often acts as a source of Ag+ inside the cell. One of the main mechanisms of toxicity is that it causes oxidative stress through the generation of reactive oxygen species and causes damage to cellular components including DNA damage, activation of antioxidant enzymes, depletion of antioxidant molecules (e.g., glutathione, binding and disabling of proteins, and damage to the cell membrane. Several major questions remain to be answered: (1 the toxic contribution from the ionic form versus the nano-form; (2 key enzymes and signaling pathways responsible for the toxicity; and (3 effect of coexisting molecules on the toxicity and its relationship to surface coating.

  14. Toxicity of environmental chemicals and their mixtures to selected aquatic organisms. Behaviour, development and biochemistry; Toxizitaet von Umweltchemikalien und deren Mischungen auf ausgewaehlte aquatische Organismen. Verhalten, Entwicklung und Biochemie

    Energy Technology Data Exchange (ETDEWEB)

    Kienle, Cornelia

    2009-04-28

    In this work, the effects of various single substances (pesticides and metals) as well as binary mixtures of them on zebrafish (Danio rerio) embryos and larvae were assessed on biochemical, developmental, and organism levels. The influence of oxygen depletion on the toxicity of substances was included as an additional interacting factor. To analyse complex interactions, the predator-prey behaviour between zebrafish and chironomid larvae (Chironomus riparius) was investigated. Another aspect of this work were studies on complex mixtures of hydrocarbons such as the water accommodated fraction of crude oil, and their effects on the behaviour of marine amphipods (Corophium volutator), as well as semi-field experiments with freshwater amphipods (Gammarus pulex). My investigations showed that effects of various substances in environmentally relevant concentration ranges are exerted on different levels of biological organisation, both in amphipods and fish. It could be shown that abiotic parameters modify the effects of pollutants. When investigating mixtures of substances with similar or different modes of action, additivity occurred in the majority of cases which usually were consistent for all investigated parameters (enzyme activity, locomotor activity, developmental impairment, mortality). Effects of the neurotoxic insecticide chlorpyrifos on the interactions between fish and chironomids could be detected in environmentally relevant concentration ranges. The effects of the water accommodated fraction of crude oil which represents a great risk for aquatic organisms in costal habitats were displayed by alterations in the behaviour of the marine amphipod Corophium volutator. For a continuous monitoring of water quality in monitoring stations, the resident amphipod Gammarus pulex proved to be a suitable and relevant test organism, as it responds sensitive to complex mixtures of pollutants in surface waters. In summary, behavioural parameters proved to be integrative

  15. Olfactory toxicity in fishes.

    Science.gov (United States)

    Tierney, Keith B; Baldwin, David H; Hara, Toshiaki J; Ross, Peter S; Scholz, Nathaniel L; Kennedy, Christopher J

    2010-01-21

    Olfaction conveys critical environmental information to fishes, enabling activities such as mating, locating food, discriminating kin, avoiding predators and homing. All of these behaviors can be impaired or lost as a result of exposure to toxic contaminants in surface waters. Historically, teleost olfaction studies have focused on behavioral responses to anthropogenic contaminants (e.g., avoidance). More recently, there has been a shift towards understanding the underlying mechanisms and functional significance of contaminant-mediated changes in fish olfaction. This includes a consideration of how contaminants affect the olfactory nervous system and, by extension, the downstream physiological and behavioral processes that together comprise a normal response to naturally occurring stimuli (e.g., reproductive priming or releasing pheromones). Numerous studies spanning several species have shown that ecologically relevant exposures to common pollutants such as metals and pesticides can interfere with fish olfaction and disrupt life history processes that determine individual survival and reproductive success. This represents one of the pathways by which toxic chemicals in aquatic habitats may increasingly contribute to the decline and at-risk status of many commercially and ecologically important fish stocks. Despite our emerging understanding of the threats that pollution poses for chemical communication in aquatic communities, many research challenges remain. These include: (1) the determination of specific mechanisms of toxicity in the fish olfactory sensory epithelium; (2) an understanding of the impacts of complex chemical mixtures; (3) the capacity to assess olfactory toxicity in fish in situ; (4) the impacts of toxins on olfactory-mediated behaviors that are still poorly understood for many fish species; and (5) the connections between sublethal effects on individual fish and the long-term viability of wild populations. This review summarizes and integrates

  16. EnviroAtlas - Portland, ME - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, green space, wetland, and agriculture. Impervious is...

  17. EnviroAtlas - Cleveland, OH - Park Access by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included...

  18. EnviroAtlas - Portland, OR - Park Access by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included...

  19. EnviroAtlas - Durham, NC - Park Access by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included...

  20. EnviroAtlas - Pittsburgh, PA - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, and green space. Forest is combination of trees and...

  1. EnviroAtlas - Paterson, NJ - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, and green space. Forest is just trees and forest....

  2. EnviroAtlas - Portland, OR - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, and green space. Forest is combination of trees and...

  3. EnviroAtlas - Woodbine, IA - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, and green space. Forest is combination of trees and...

  4. EnviroAtlas - Milwaukee, WI - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, wetlands, agriculture, and green space. Forest is a...

  5. EnviroAtlas - New York, NY - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the New York, NY EnviroAtlas community. The block groups are from the US Census Bureau and are included/excluded based...

  6. EnviroAtlas - Tampa, FL - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, green space, wetland, and agriculture. Impervious is...

  7. EnviroAtlas - Fresno, CA - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, and green space. Forest is combination of trees and...

  8. EnviroAtlas - Memphis, TN - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, green space, agriculture, and wetlands. Forest is...

  9. EnviroAtlas - Cleveland, OH - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, green space, and wetlands. In this community, forest...

  10. EnviroAtlas - Austin, TX - Park Access by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included...

  11. EnviroAtlas - Paterson, NJ - Park Access by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included...

  12. EnviroAtlas - Woodbine, IA - Park Access by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included...

  13. EnviroAtlas - Milwaukee, WI - Park Access by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included...

  14. EnviroAtlas - Memphis, TN - Park Access by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included...

  15. EnviroAtlas - Portland, ME - Park Access by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included...

  16. EnviroAtlas - Austin, TX - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, green space, and agriculture. Forest is defined as...

  17. EnviroAtlas - Phoenix, AZ - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, agriculture, and green space. Forest is combination...

  18. EnviroAtlas - Phoenix, AZ - Park Access by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included...

  19. FLUORIDE TOXICITY – A HARSH REALITY

    Directory of Open Access Journals (Sweden)

    Bandlapalli Pavani

    2011-04-01

    Full Text Available There are many incidents of fluoride toxicity whether it is acute or chronic. Fluoride toxicity is an environmental hazard which arises from the upper layers of geological crust and is dissolved in water. Prolonged drinking of such water causes chronic fluoride toxicity. Use of fluoride containing compounds for various purposes such as dental products, metal, glass, refrigerator and chemical industries act as a source of fluoride poisoning and increase the risk of toxicity. This review reflects the deleterious effects of fluorides on various organs in the physiological system.

  20. PET吹灌旋一体机及其在环保型轻量瓶装水生产线中的应用%The Application of the Blow-Fill-Cap BFC-Block in Bottled Water Production Line of Environmentally Friendly and Light-weight-situation

    Institute of Scientific and Technical Information of China (English)

    朱建锋; 张洁生

    2013-01-01

    The article describes the structure and composition of the Blow-Fill-Cap BFC-Block and process,explaining the necessity and significance of the environment-friendly light flask,to further illustrate the application of the Blow-Fill-Cap BFC-Block in bottled water production line of environmentally friendly lightweight-situation .%介绍了吹灌旋一体机的主要结构及其组成和工艺流程,同时说明环保型轻量瓶技术产生的必要性和意义,进一步说明吹灌旋一体机在环保型轻量瓶装水生产线上应用情况.

  1. What correlation does the electron structure of environmental hormones have with manifestation of their toxicity and biological activity. Application of the hardness conception to biology; Kankyo horumon no denshi kozo wa sono dokusei ya seibutsu kassei no hatsugen ni donoyona sokansei wo motsunode aroka. Hardness gainen no seibutsugaku eno oyo

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, S.; Tanaka, A. [Showa College of Pharmaceutical Sciences, Tokyo (Japan); Sameshima, K. [Fujitsu Ltd., Tokyo (Japan)

    1999-01-01

    This paper indicates that the relationship between toxicity and biological activity of environmental hormones such as dioxin and their chemical structures may be predicted by using parameters (physical quantity) derived from the chemical hardness conception. According to this conception, softness and hardness of molecules are important in addition to electron receptivity and donation properties of molecules. Soft compounds facilitate electrons to migrate. Chlorine displacement of dioxin skeleton to 2nd, 3rd, 7th and 8th orders softens the molecules and displacement to 1st, 4th, 6th and 9th orders hardens them. The toxicity and biological activity of the environmental hormones cannot be explained only with the fit model of key-keyhole with the counterpart they act on (receptor). The softer the chemical hardness, the greater the toxicity and biological activity. Development has been made on an absolute hardness versus absolute electrical negative activity diagram to learn electron structure of molecules. This diagram indicates that the toxicity of dioxin depends more strongly on the chemical hardness than the strength of the electrical negativity, and the softer the hardness, the stronger the toxicity. (NEDO)

  2. Right bundle branch block

    DEFF Research Database (Denmark)

    Bussink, Barbara E; Holst, Anders Gaarsdal; Jespersen, Lasse;

    2013-01-01

    AimsTo determine the prevalence, predictors of newly acquired, and the prognostic value of right bundle branch block (RBBB) and incomplete RBBB (IRBBB) on a resting 12-lead electrocardiogram in men and women from the general population.Methods and resultsWe followed 18 441 participants included.......5%/2.3% in women, P Right bundle branch block was associated with significantly.......60-1.62). The presence of IRBBB was not associated with any adverse outcome.ConclusionIn this cohort study, RBBB and IRBBB were two to three times more common among men than women. Right bundle branch block was associated with increased cardiovascular risk and all-cause mortality, whereas IRBBB was not. Contrary...

  3. 78 FR 52860 - Electronic Reporting of Toxics Release Inventory Data

    Science.gov (United States)

    2013-08-27

    ... to report non- trade-secret Toxics Release Inventory (TRI) forms to EPA using electronic software... AGENCY 40 CFR Part 372 RIN 2025-AA30 Electronic Reporting of Toxics Release Inventory Data AGENCY..., Toxics Release Inventory Program Division, Mailcode 2844T, OEI, Environmental Protection Agency,...

  4. [Advances in non-carcinogenic toxicity of trichloroethylene].

    Science.gov (United States)

    Huang, Peiwu; Li, Xuan; Liu, Wei; Liu, Jianjun

    2015-09-01

    Trichloroethylene (TCE) is a widely used organic solvent and an important industrial material. Due to mass production and use, and improper waste disposal, TCE has become a common environmental contaminant, so there is a wide range of occupationally and environmentally exposed population. Occupational and environmental exposure to TCE can produce toxic effects on multiple organs and systems. This paper is a review of the immunotoxicity, reproductive toxicity, neurotoxicity, teratogenic effect and other non-carcinogenic toxic effects of TCE from the aspects of epidemiological study, experimental evidence on animals and toxic mechanisms.

  5. Effects of Block Scheduling

    Directory of Open Access Journals (Sweden)

    William R. Veal

    1999-09-01

    Full Text Available This study examined the effects of a tri-schedule on the academic achievement of students in a high school. The tri-schedule consists of traditional, 4x4 block, and hybrid schedules running at the same time in the same high school. Effectiveness of the schedules was determined from the state mandated test of basic skills in reading, language, and mathematics. Students who were in a particular schedule their freshman year were tested at the beginning of their sophomore year. A statistical ANCOVA test was performed using the schedule types as independent variables and cognitive skill index and GPA as covariates. For reading and language, there was no statistically significant difference in test results. There was a statistical difference mathematics-computation. Block mathematics is an ideal format for obtaining more credits in mathematics, but the block format does little for mathematics achievement and conceptual understanding. The results have content specific implications for schools, administrations, and school boards who are considering block scheduling adoption.

  6. Concrete Block Pavements

    Science.gov (United States)

    1983-03-01

    1967, Cedergren 1974, Federal Highway .’,U .. V,47 -’":: 37 Administration 1980). Block pavements have essentially the same prob- lems with moisture...Vicksburg, Miss. Cedergren , H. R. 1974. Drainage of Highway and Airfield Pavements, John Wiley and Sons, New VOk. I Cement and Concrete Association

  7. Block That Pain!

    Science.gov (United States)

    ... along with the National Institute of Dental and Craniofacial Research (NIDCR) and the National Institute of General Medical Sciences (NIGMS). This finding shows that a specific combination of two molecules can block only pain-related neurons. It holds the promise of major ...

  8. Pulmonary edema of environmental origin--newer concepts

    Energy Technology Data Exchange (ETDEWEB)

    Cordasco, E.M.; Demeter, S.R.; Kester, L.; Cordasco, M.A.; Lammert, G.; Beerel, F.

    1986-06-01

    Pulmonary edema of non-cardiac origin is usually an urgent clinical problem, which has recently increased in frequency throughout the world in the past few years. This is partly due to sociological factors and to pre-eminent advances in industrial technology. Recent severe massive toxic gas explosions have had national and worldwide implications. Therefore, urgent and appropriate therapy is of utmost importance in most of these patients. The use of high flow oxygen with Constant Positive Pressure Breathing are the main inhalational therapeutic approaches. Newer modalities of treatment include: (1) earlier Fiberoptic bronchoscopy in those individuals afflicted with aspiration problems and (2) certain specific chemical blocking agents for the management of phosgene intoxication and hydrogen sulfide toxicity. Preventive environmental measures are also important.

  9. Electric Power Research Institute, Environmental Control Technology Center monthly report to the Steering Committee, June 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-11-02

    Operations and maintenance continued this month at the Electric Power Research Institute`s Environmental Control Technology Center. Testing on the 4.0 MW Pilot FGD unit continued this month with High Velocity Scrubbing and the Tampa Electric Company (TECO) Tailored Collaboration test block. Additionally, Phase III of the Toxics Removal/Carbon Injection test block was conducted concurrently with FGD testing. At the beginning of the month, a second phase of third-party testing began for Suncor, Inc. The Suncor Gypsum Sample Collection test block (MSUN) began on June 5 on the 0.4 MW Mini-Pilot Wet FGD unit. Testing was completed on June 13. On the Cold-Side Selective Catalytic Reduction (SCR) unit, testing continued this month as ammonia slip measurements were conducted under low catalyst inlet temperatures and at baseline conditions.

  10. The cellular toxicity of aluminium.

    Science.gov (United States)

    Exley, C; Birchall, J D

    1992-11-07

    Aluminium is a serious environmental toxicant and is inimical to biota. Omnipresent, it is linked with a number of disorders in man including Alzheimer's disease, Parkinson's dementia and osteomalacia. Evidence supporting aluminium as an aetiological agent in such disorders is not conclusive and suffers principally from a lack of consensus with respect to aluminium's toxic mode of action. Obligatory to the elucidation of toxic mechanisms is an understanding of the biological availability of aluminium. This describes the fate of and response to aluminium in any biological system and is thus an important influence of the toxicity of aluminium. A general theme in much aluminium toxicity is an accelerated cell death. Herein mechanisms are described to account for cell death from both acute and chronic aluminium challenges. Aluminium associations with both extracellular surfaces and intracellular ligands are implicated. The cellular response to aluminium is found to be biphasic having both stimulatory and inhibitory components. In either case the disruption of second messenger systems is observed and GTPase cycles are potential target sites. Specific ligands for aluminium at these sites are unknown though are likely to be proteins upon which oxygen-based functional groups are orientated to give exceptionally strong binding with the free aluminium ion.

  11. Recovery from blocking between outcomes.

    Science.gov (United States)

    Wheeler, Daniel S; Miller, Ralph R

    2005-10-01

    Contemporary associative learning research largely focuses on cue competition phenomena that occur when 2 cues are paired with a common outcome. Little research has been conducted to investigate similar phenomena occurring when a single cue is trained with 2 outcomes. Three conditioned lick suppression experiments with rats assessed whether treatments known to alleviate blocking between cues would also attenuate blocking between outcomes. In Experiment 1, conditioned responding recovered from blocking between outcomes when a long retention interval was interposed between training and testing. Experiment 2 obtained recovery from blocking between outcomes when the blocking outcome was extinguished after the blocking treatment. In Experiment 3, a recovery from blocking between outcomes occurred when a reminder stimulus was presented in a novel context prior to testing. Collectively, these studies demonstrate that blocking of outcomes, like blocking of cues, appears to be caused by a deficit in the expression of an acquired association.

  12. SUPERFICIAL CERVICAL PLEXUS BLOCK

    Directory of Open Access Journals (Sweden)

    Komang Mega Puspadisari

    2014-01-01

    Full Text Available Superficial cervical plexus block is one of the regional anesthesia in  neck were limited to thesuperficial fascia. Anesthesia is used to relieve pain caused either during or after the surgery iscompleted. This technique can be done by landmark or with ultrasound guiding. The midpointof posterior border of the Sternocleidomastoid was identified and the prosedure done on thatplace or on the level of cartilage cricoid.

  13. EnviroAtlas - Green Bay, WI - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 155 block groups in Green Bay, Wisconsin. Carbon attributes, temperature reduction,...

  14. EnviroAtlas - Des Moines, IA - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 312 block groups in Des Moines, IA. Carbon attributes, temperature reduction,...

  15. EnviroAtlas - New Haven, CT - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 444 block groups in New Haven, Connecticut. Carbon attributes, temperature reduction,...

  16. EnviroAtlas - New York City, NY - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 6,378 block groups in New York City, New York. Carbon attributes, temperature...

  17. EnviroAtlas - New Bedford, MA - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 128 block group in New Bedford, Massachusetts. Carbon attributes, temperature...

  18. EnviroAtlas - Minneapolis/St. Paul, MN - Ecosystem Services by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 1,772 block groups in Minneapolis/St. Paul, Minnesota. Carbon attributes, temperature...

  19. Managing access block.

    Science.gov (United States)

    Cameron, Peter; Scown, Paul; Campbell, Donald

    2002-01-01

    There is pessimism regarding the ability of the Acute Health Sector to manage access block for emergency and elective patients. Melbourne Health suffered an acute bed crisis in 2001 resulting in record ambulance diversions and emergency department (ED) delays. We conducted an observational study to reduce access block for emergency patients whilst maintaining elective throughput at Melbourne Health. This involved a clinician-led taskforce using previously proven principles for organisational change to implement 51 actions to improve patient access over a three-month period. The primary outcome measures were ambulance diversion, emergency patients waiting more than 12 hours for an inpatient bed, elective throughput and theatre cancellations. Despite a reduction in multi-day bed numbers all primary objectives were met, ambulance diversion decreased to minimal levels, 12-hour waits decreased by 40% and elective throughput was maintained. Theatre cancellations were also minimised. We conclude that access block can be improved by clinician-led implementation of proven process improvements over a short time frame. The ability to sustain change over the longer term requires further study.

  20. Influence of developmental stage, salts and food presence on various end points using Caenorhabditis elegans for aquatic toxicity testing

    Energy Technology Data Exchange (ETDEWEB)

    Donkin, S.G.; Williams, P.L. [Univ. of Georgia, Athens, GA (United States)

    1995-12-01

    This study used a randomized block design to investigate the importance of several variables in using the free-living soil nematode, Caenorhabditis elegans, for aquatic toxicity testing. Concentration-response data were obtained on nematodes of various developmental stages exposed to four metals (Cd, Pb, Cu, and Hg) and a water-soluble organic toxicant, sodium pentachlorophenate (PCP), under conditions of varied solvent medium (with or without salts and with or without a bacterial food source). The end points measured were 24- and 96-h mortality LC50 value, as well as development of larval stages to adulthood and evidence of reproduction. The results suggest that nematodes of various ages respond similarity to a given toxicant for all end points measured, although adults cultured from eggs appeared more sensitive than adults cultured from dauer larvae. The most important environmental variable in determining toxicity was the medium in which the tests were conducted. The presence of potassium and sodium salts in the medium significantly (p < 0.05) reduced the toxicity of many test samples. The presence of bacteria had little effect on 24-h tests with salts, but was important in 96-h survival and development. Based on sensitivity and ease of handling, adults cultured from eggs are recommended in both 24h and 96-h tests.

  1. Block Transfer Handbook: Constructing and Negotiating Block Transfer Agreements.

    Science.gov (United States)

    Finlay, Finola

    The purpose of this handbook is to provide resources for institutions or articulation committees who are engaged in the task of investigating the feasibility of block transfer agreements. Block transfer is the process whereby a block of credits is granted to students who have successfully completed a certificate, diploma, or cluster of courses…

  2. Demographic Data - MDC_Block

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — A polygon feature class of Miami-Dade Census 2000 Blocks. Census blocks are areas bounded on all sides by visible and/or invisible features shown on a map prepared...

  3. Habitat Blocks and Wildlife Corridors

    Data.gov (United States)

    Vermont Center for Geographic Information — Habitat blocks are areas of contiguous forest and other natural habitats that are unfragmented by roads, development, or agriculture. Vermonts habitat blocks are...

  4. Toxic Plant Resources in Panxi Area

    Institute of Scientific and Technical Information of China (English)

    XU Yun; SU Chunjiang; ZHENG Yuanchang

    2007-01-01

    Panxi Area is abundant in plant resources, among which toxic plants are of great value in terms of exploitation. This paper is an initiative study (via field as well as literature investigation) of the categories, distributions, and reserves of toxic plant resources in Panxi Area. The study reveals that there are 51 families (210 species) of toxic plants evenly distributed in Panxi Area, of which more than 40 species grow in all counties in the area, and more than 14 species total a reserve more than 1.0×105kg. These toxic plants are of great applications to medicine, gardening, biopesticide industry, environmental engineering, and oil manufacturing. Rhododendron molle, Anisodus acutangulus, Arisaema erubesocens, Stellera chamaejasme, Rhytolacca acinosa, Rheum officinale, and Azadiralta indica etc are the typical toxic plants with great value of exploitation in Panxi Area.

  5. Toxicities of selected substances to freshwater biota

    Energy Technology Data Exchange (ETDEWEB)

    Hohreiter, D.W.

    1980-05-01

    The amount of data available concerning the toxicity of various substances to freshwater biota is so large that it is difficult to use in a practical situation, such as environmental impact assessment. In this document, summary tables are presented showing acute and/or chronic toxicity of selected substances for various groups of aquatic biota. Each entry is referenced to its original source so that details concerning experimental conditions may be consulted. In addition, general information concerning factors modifying toxicity, synergisms, evidence of bioaccumulation, and water quality standards and criteria for the selected substances is given. The final table is a general toxicity table designed to provide an easily accessible and general indication of toxicity of selected substances in aquatic systems.

  6. Porous block nanofiber composite filters

    Energy Technology Data Exchange (ETDEWEB)

    Ginley, David S.; Curtis, Calvin J.; Miedaner, Alexander; Weiss, Alan J.; Paddock, Arnold

    2016-08-09

    Porous block nano-fiber composite (110), a filtration system (10) and methods of using the same are disclosed. An exemplary porous block nano-fiber composite (110) includes a porous block (100) having one or more pores (200). The porous block nano-fiber composite (110) also includes a plurality of inorganic nano-fibers (211) formed within at least one of the pores (200).

  7. Properties of blocked linear systems.

    Science.gov (United States)

    Chen, Weitian; Anderson, Brian D O; Deistler, Manfred; Filler, Alexander

    2012-10-01

    This paper presents a systematic study on the properties of blocked linear systems that have resulted from blocking discrete-time linear time invariant systems. The main idea is to explore the relationship between the blocked and the unblocked systems. Existing results are reviewed and a number of important new results are derived. Focus is given particularly on the zero properties of the blocked system as no such study has been found in the literature.

  8. Appropriate schemata and building blocks

    Institute of Scientific and Technical Information of China (English)

    Yang Haijun; Li Minqiang

    2005-01-01

    Appropriate schemata as a novel concept to characterize building blocks are introduced, and then, the traits of appropriate schemata are presented. The effects of building blocks by search operators are analyzed. Hence, the experiments on RR-8X8 are employed to verify that appropriate schemata construct the building blocks. The validity of appropriate schemata and building blocks from the views of theory and practice is presented.

  9. Blocking the Hawking radiation

    DEFF Research Database (Denmark)

    Autzen, M.; Kouvaris, C.

    2014-01-01

    grows after its formation (and eventually destroys the star) instead of evaporating. The fate of the black hole is dictated by the two opposite mechanics, i.e., accretion of nuclear matter from the center of the star and Hawking radiation that tends to decrease the mass of the black hole. We study how...... the assumptions for the accretion rate can in fact affect the critical mass beyond which a black hole always grows. We also study to what extent degenerate nuclear matter can impede Hawking radiation due to the fact that emitted particles can be Pauli blocked at the core of the star....

  10. Property Blocks: Games and Activities.

    Science.gov (United States)

    Humphreys, Alan, Ed.; Dailey, Jean, Ed.

    This pamphlet describes the property blocks produced by MINNEMAST, and discusses their use in the development of thinking processes. Classification systems, including block diagrams and tree diagrams, are discussed. Sixteen classroom activities and eleven games which use the blocks are described. Suggestions to the teacher for further reading are…

  11. EnviroAtlas - Des Moines, IA - Residents with Minimal Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  12. EnviroAtlas - New York, NY - Residents with Minimal Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  13. EnviroAtlas - Minneapolis/St. Paul, MN - Residents with Minimal Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  14. EnviroAtlas - New Haven, CT - Residents with Minimal Potential Window Views of Trees by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the total block group population and the percentage of the block group population that has little access to potential window views of...

  15. Environmental licensing in the oil and gas activities and implications regarding to the fulfilment of the period of bidding blocks; O licenciamento ambiental nas atividades petroliferas e as aplicacoes atinentes ao cumprimento de prazo de blocos licitados

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcante, Hellen Priscilla Marinho [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Faculdade de Direito], email: hellen.cav@gmail.com

    2009-08-15

    The uncontrolled population growth, the intensification of economic activities arising from the unbridled quest for profit and the ignorance about the existing environmental legislation has brought serious consequences to the natural resources of our planet and causing imbalance to ecosystems. The environment, being a common good and thus belong to the community, not to institutions or specific individuals, should be protected by all, including here also the Government. Thus, demonstrating their concern for the protection of nature and rational use of the environment, the State issued some legal documents in order to impose limits on human action, to prevent environmental damage and at the same time meeting the concept of development sustainable. This issue will be examined in this work, on the focus of licensing the activities of oil and natural gas.

  16. Evaluation of nano-specific toxicity of zinc oxide, copper oxide, and silver nanoparticles through toxic ratio

    Science.gov (United States)

    Zhang, Weicheng; Liu, Xiawei; Bao, Shaopan; Xiao, Bangding; Fang, Tao

    2016-12-01

    For safety and environmental risk assessments of nanomaterials (NMs) and to provide essential toxicity data, nano-specific toxicities, or excess toxicities, of ZnO, CuO, and Ag nanoparticles (NPs) (20, 20, and 30 nm, respectively) to Escherichia coli and Saccharomyces cerevisiae in short-term (6 h) and long-term (48 h) bioassays were quantified based on a toxic ratio. ZnO NPs exhibited no nano-specific toxicities, reflecting similar toxicities as ZnO bulk particles (BPs) (as well as zinc salt). However, CuO and Ag NPs yielded distinctly nano-specific toxicities when compared with their BPs. According to their nano-specific toxicities, the capability of these NPs in eliciting hazardous effects on humans and the environment was as follows: CuO > Ag > ZnO NPs. Moreover, long-term bioassays were more sensitive to nano-specific toxicity than short-term bioassays. Overall, nano-specific toxicity is a meaningful measurement to evaluate the environmental risk of NPs. The log T e particle value is a useful parameter for quantifying NP nano-specific toxicity and enabling comparisons of international toxicological data. Furthermore, this value could be used to determine the environmental risk of NPs.

  17. Humanoid by ROBO-BLOCK

    Science.gov (United States)

    Niimi, Hirofumi; Koike, Minoru; Takeuchi, Seiichi; Douhara, Noriyoshi

    2007-12-01

    Humanoid by ROBO-BLOCK (robot block system) and the rational formula of robots were proposed. ROBO-BLOCK is composed of servo motors, the parts for servomotor rotor, the brackets for servomotor fixation, the board parts and the controllers. A robot can be assembled easily by ROBO-BLOCK. Meanwhile, it is convenient when the structure of the robot can be described easily as a character. The whole structure of the robot is expressed as rational formula of the robot to show molecule structure in chemistry. ROBO-BLOCK can be useful for not only the research but also the education. Creative student experiment was done in the college of industrial technology.

  18. Lead toxicity: Current concerns

    Energy Technology Data Exchange (ETDEWEB)

    Goyer, R.A. (Univ. of Western Ontario, London (Canada))

    1993-04-01

    Over the 20-year period since the first issue of Environmental Health Perspectives was published, there has been considerable progress in the understanding of the potential toxicity of exposure to lead. Many of these advances have been reviewed in published symposia, conferences, and review papers in EHP. This brief review identifies major advances as well as a number of current concerns that present opportunities for prevention and intervention strategies. The major scientific advance has been the demonstration that blood lead (PbB) levels of 10-15 micrograms/dL in newborn and very young infants result in cognitive and behavioral deficits. Further support for this observation is being obtained by prospective or longitudinal studies presently in progress. The mechanism(s) for the central nervous system effects of lead is unclear but involve lead interactions within calcium-mediated intracellular messenger systems and neurotransmission. Effects of low-level lead exposure on blood pressure, particularly in adult men, may be related to the effect of lead on calcium-mediated control of vascular smooth muscle contraction and on the renin-angiotensin system. Reproductive effects of lead have long been suspected, but low-level effects have not been well studied. Whether lead is a carcinogen or its association with renal adenocarcinoma is a consequence of cystic nephropathy is uncertain. Major risk factors for lead toxicity in children in the United States include nutrition, particularly deficiencies of essential metals, calcium, iron, and zinc, and housing and socioeconomic status. A goal for the year 2000 is to reduce prevalence of blood lead levels exceeding 15 micrograms/dL. 97 refs.

  19. Marine toxic substance and other data from bottle casts from NOAA Ship DISCOVERER as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1978-05-05 to 1978-05-16 (NCEI Accession 7900274)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from bottle casts from NOAA Ship DISCOVERER from 05 May 1978 to 16 May 1978. Data were collected by the Pacific...

  20. 专题演讲-W3药物和环境毒物的免疫毒性与神经毒性%WORKSHOPS-W3: Immunotoxicity and Neurotoxicity of Pharmaceuticals and Environmental Toxic Substances

    Institute of Scientific and Technical Information of China (English)

    J SAWADA; S HISADA; WU Yi-Ming; ZHANG Qiao; Y HEO

    2006-01-01

    @@ Toxicity to the immune system encompasses suppression or enhancement of the immune response. Suppression of the immune response can lead to decreased host resistance to infectious agents or tumor cells. Enhancing the immune response can exaggerate autoimmune diseases or hypersensitivity.

  1. Marine toxic substance and other data from bottle casts from the Beaufort Seas as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 01 August 1970 (NODC Accession 8100505)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from bottle casts in the Beaufort Sea from 01 August 1970. Data were collected by the University of Alaska -...

  2. Marine toxic substance and other data from bottle casts in the Bering Sea from NOAA Ship DISCOVERER as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1981-05-11 to 1981-06-04 (NODC Accession 8200099)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from bottle casts in the Bering Sea from NOAA Ship DISCOVERER from 11 May 1981 to 04 June 1981. Data were...

  3. Marine toxic substance and other data from bottle casts from the USCGC GLACIER and other platforms as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 03 August 1977 to 03 September 1977 (NODC Accession 8000247)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from bottle casts from the USCGC GLACIER and other platforms from 03 August 1977 to 03 September 1977. Data were...

  4. Marine toxic substance and other data from bottle casts from the Beaufort Sea as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 01 June 1971 (NODC Accession 8100514)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from bottle casts in the Beaufort Sea from 01 June 1971. Data were collected by the University of Alaska -...

  5. Marine toxic substance and other data from bottle casts from NOAA Ship DISCOVERER and other platforms as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1977-03-22 to 1978-08-18 (NODC Accession 8000246)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from bottle casts from NOAA Ship DISCOVERER and other platforms from 22 March 1977 to 18 August 1978. Data were...

  6. Marine toxic substance and other data from grab casts from the ACONA and other platforms as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 01 July 1974 to 31 August 1978 (NODC Accession 8100533)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from grab casts from the ACONA and other platforms from 01 July 1974 to 31 August 1978. Data were collected by...

  7. Marine bird sighting, marine toxic substance, and other data from NOAA Ship DISCOVERER and other platforms as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1976-03-25 to 1978-05-02 (NODC Accession 7900171)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine bird sighting, marine toxic substance, and other data were collected from NOAA Ship DISCOVERER and other platforms from 25 March 1976 to 02 May 1978. Data...

  8. Marine toxic substance and other data from the Gulf of Alaska from NOAA Ship DISCOVERER as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1977-05-05 to 1979-05-18 (NODC Accession 8100493)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected in the Gulf of Alaska from NOAA Ship DISCOVERER from 05 May 1977 to 18 May 1979. Data were collected by the...

  9. Marine toxic substance and other data from bottle casts from the NOAA Ship SURVEYOR as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 13 August 1980 to 21 February 1981 (NODC Accession 8100531)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from bottle casts from the NOAA Ship SURVEYOR from 13 August 1980 to 21 February 1981. Data were collected by...

  10. Marine toxic substance and other data from pump casts from NOAA Ship DISCOVERER as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1977-04-03 to 1979-07-25 (NODC Accession 8100691)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from pump casts from NOAA Ship DISCOVERER from 03 April 1977 to 25 July 1979. Data were collected by the Pacific...

  11. Marine toxic substance and other data from bottle casts from NOAA Ship DISCOVERER and other platforms as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1977-11-11 to 1978-08-01 (NODC Accession 7900267)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from bottle casts from NOAA Ship DISCOVERER and other platforms from 11 November 1977 to 01 August 1978. Data...

  12. Marine toxic substance and other data from grab casts in the Bering Sea from the USCGC POLAR STAR as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 29 April 1980 to 28 June 1980 (NODC Accession 8100551)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from grab casts in the Bering Sea from the USCGC POLAR STAR from 29 April 1980 to 28 June 1980. Data were...

  13. Toxic substance and other data from bottle casts in the Gulf of Alaska from NOAA Ship DISCOVERER as part of the Outer Continental Shelf Environmental Assessment Program from 1975-10-08 to 1975-11-09 (NODC Accession 7600630)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Toxic substances and pollutants data were collected from bottle casts in the Gulf of Alaska from NOAA Ship DISCOVERER. Data were collected by Pacific Marine...

  14. Marine toxic substance and other data from bottle casts from NOAA Ship DISCOVERER as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 1979-05-07 to 1979-07-18 (NODC Accession 8000466)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine toxic substance and other data were collected from bottle casts from NOAA Ship DISCOVERER from 07 May 1979 to 18 July 1979. Data were collected by the Pacific...

  15. Marine Toxic Substance and other data from core casts from the ALUMINIAK in the Beaufort Sea as part of Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 14 August 1977 to 25 August 1977 (NODC Accession 7900067)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Marine Toxic Substance and other data were collected from core casts in the Beaufort Sea from the ALUMINIAK. Data were collected by the University of Alaska -...

  16. Spintronics: Conceptual Building Blocks

    Science.gov (United States)

    Ansermet, J.-Ph.

    The purpose of this introduction to spintronics is to provide some elementary description of its conceptual building blocks. Thus, it is intended for a newcomer to the field. After recalling rudimentary descriptions of spin precession and spin relaxation, spin-dependent transport is treated within the Boltzmann formalism. This suffices to introduce key notions such as the spin asymmetry of the conductivities in the two-current model, the spin diffusion length, and spin accumulation. Two basic mechanisms of spin relaxation are then presented, one arising from spin-orbit scattering and the other from electron-magnon collisions. Finally, the action of a spin-polarized current on magnetization is presented in a thermodynamics framework. This introduces the notion of spin torque and the characteristic length scale over which the transverse spin polarization of conduction electron decays as it is injected into a magnet.

  17. Photovoltaic building blocks

    DEFF Research Database (Denmark)

    Hanberg, Peter Jesper; Jørgensen, Anders Michael

    2014-01-01

    it directcompetitive with fossil energy sources a further reduction is needed. By increasing the efficiency of the solar cells one gain an advantage through the whole chain of cost. So that per produced Watt of power less material is spent, installation costs are lower, less area is used etc. With an average...... efficiency of about 15% for commercial Silicon solar cells there is still much to gain. DTU Danchip provides research facilities, equipment and expertise for the building blocks that comprises fabricating the efficient solar cell. In order to get more of the sun light into the device we provide thin film......Photovoltaics (PV), better known as solar cells, are now a common day sight on many rooftops in Denmark.The installed capacity of PV systems worldwide is growing exponentially1 and is the third most importantrenewable energy source today. The cost of PV is decreasing fast with ~10%/year but to make...

  18. Celiac ganglia block

    Energy Technology Data Exchange (ETDEWEB)

    Akinci, Devrim [Department of Radiology, Hacettepe University School of Medicine, Sihhiye, 06100 Ankara (Turkey); Akhan, Okan [Department of Radiology, Hacettepe University School of Medicine, Sihhiye, 06100 Ankara (Turkey)]. E-mail: oakhan@hacettepe.edu.tr

    2005-09-01

    Pain occurs frequently in patients with advanced cancers. Tumors originating from upper abdominal viscera such as pancreas, stomach, duodenum, proximal small bowel, liver and biliary tract and from compressing enlarged lymph nodes can cause severe abdominal pain, which do not respond satisfactorily to medical treatment or radiotherapy. Percutaneous celiac ganglia block (CGB) can be performed with high success and low complication rates under imaging guidance to obtain pain relief in patients with upper abdominal malignancies. A significant relationship between pain relief and degree of tumoral celiac ganglia invasion according to CT features was described in the literature. Performing the procedure in the early grades of celiac ganglia invasion on CT can increase the effectiveness of the CGB, which is contrary to World Health Organization criteria stating that CGB must be performed in patients with advanced stage cancer. CGB may also be effectively performed in patients with chronic pancreatitis for pain palliation.

  19. Atomic Basic Blocks

    Science.gov (United States)

    Scheler, Fabian; Mitzlaff, Martin; Schröder-Preikschat, Wolfgang

    Die Entscheidung, einen zeit- bzw. ereignisgesteuerten Ansatz für ein Echtzeitsystem zu verwenden, ist schwierig und sehr weitreichend. Weitreichend vor allem deshalb, weil diese beiden Ansätze mit äußerst unterschiedlichen Kontrollflussabstraktionen verknüpft sind, die eine spätere Migration zum anderen Paradigma sehr schwer oder gar unmöglich machen. Wir schlagen daher die Verwendung einer Zwischendarstellung vor, die unabhängig von der jeweils verwendeten Kontrollflussabstraktion ist. Für diesen Zweck verwenden wir auf Basisblöcken basierende Atomic Basic Blocks (ABB) und bauen darauf ein Werkzeug, den Real-Time Systems Compiler (RTSC) auf, der die Migration zwischen zeit- und ereignisgesteuerten Systemen unterstützt.

  20. Toxic Amblyopia (Nutritional Amblyopia)

    Science.gov (United States)

    ... Contact Lenses Additional Content Medical News Toxic Amblyopia (Nutritional Amblyopia) By James Garrity, MD, Mayo Clinic NOTE: ... or methyl alcohol), antifreeze, or certain drugs. A nutritional deficiency or toxic substance is often the cause ...

  1. 2015 TRI National Analysis: Toxics Release Inventory Releases at Various Summary Levels

    Data.gov (United States)

    U.S. Environmental Protection Agency — The TRI National Analysis is EPA's annual interpretation of TRI data at various summary levels. It highlights how toxic chemical wastes were managed, where toxic...

  2. 2014 TRI National Analysis: Toxic Release Inventory Releases at Various Summary Levels

    Data.gov (United States)

    U.S. Environmental Protection Agency — The TRI National Analysis is EPA's annual interpretation of TRI data at various summary levels. It highlights how toxic chemical wastes were managed, where toxic...

  3. TOXICITY COMPARISON OF BIOSURFACTANTS AND SYNTHETIC SURFACTANTS USED IN OIL SPILL REMEDIATION TO TWO ESTUARINE SPECIES

    Science.gov (United States)

    The relative environmental toxicities of synthetic and biogenic surfactants used in oil spill remediation efforts are not well understood. Acute and chronic toxicities of three synthetic surfactants and three microbially produced surfactants were determined and compared in this s...

  4. Risk-Screening Environmental Indicators (RSEI)

    Data.gov (United States)

    U.S. Environmental Protection Agency — EPA’s Risk-Screening Environmental Indicators (RSEI) is a geographically-based model that helps policy makers and communities explore data on releases of toxic...

  5. Skewed Riskscapes and Environmental Injustice: A Case Study of Metropolitan St. Louis

    Science.gov (United States)

    Abel, Troy D.

    2008-08-01

    This article presents a case study of Toxics Release Inventory (TRI) air pollution exposure risks across metropolitan St. Louis. The first section critically reviews environmental justice research and related barriers to environmental risk management. Second, the paper offers a conventional analysis of the spatial patterns of TRI facilities and their surrounding census block group demographics for metropolitan St. Louis. Third, the article describes the use of an exposure risk characterization for 319 manufacturers and their air releases of more than 126 toxic pollutants. This information could lead to more practical resolutions of urban environmental injustices. The analysis of TRIs across metropolitan St. Louis shows that minority and low-income residents were disproportionately closer to industrial pollution sources at nonrandom significance levels. Spatial concentrations of minority residents averaged nearly 40% within one kilometer of St. Louis TRI sites compared to 25% elsewhere. However, one-fifth of the region’s air pollution exposure risk over a decade was spatially concentrated among only six facilities on the southwestern border of East St. Louis. This disproportionate concentration of some of the greatest pollution risk would never be considered in most conventional environmental justice analyses. Not all pollution exposure risk is average, and the worst risks deserve more attention from environmental managers assessing and mitigating environmental injustices.

  6. Large Block Test Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Lin, W

    2001-12-01

    This report documents the Large-Block Test (LBT) conducted at Fran Ridge near Yucca Mountain, Nevada. The LBT was a thermal test conducted on an exposed block of middle non-lithophysal Topopah Spring tuff (Tptpmn) and was designed to assist in understanding the thermal-hydrological-mechanical-chemical (THMC) processes associated with heating and then cooling a partially saturated fractured rock mass. The LBT was unique in that it was a large (3 x 3 x 4.5 m) block with top and sides exposed. Because the block was exposed at the surface, boundary conditions on five of the six sides of the block were relatively well known and controlled, making this test both easier to model and easier to monitor. This report presents a detailed description of the test as well as analyses of the data and conclusions drawn from the test. The rock block that was tested during the LBT was exposed by excavation and removal of the surrounding rock. The block was characterized and instrumented, and the sides were sealed and insulated to inhibit moisture and heat loss. Temperature on the top of the block was also controlled. The block was heated for 13 months, during which time temperature, moisture distribution, and deformation were monitored. After the test was completed and the block cooled down, a series of boreholes were drilled, and one of the heater holes was over-cored to collect samples for post-test characterization of mineralogy and mechanical properties. Section 2 provides background on the test. Section 3 lists the test objectives and describes the block site, the site configuration, and measurements made during the test. Section 3 also presents a chronology of events associated with the LBT, characterization of the block, and the pre-heat analyses of the test. Section 4 describes the fracture network contained in the block. Section 5 describes the heating/cooling system used to control the temperature in the block and presents the thermal history of the block during the test

  7. Dimensional Reduction for Conformal Blocks

    CERN Document Server

    Hogervorst, Matthijs

    2016-01-01

    We consider the dimensional reduction of a CFT, breaking multiplets of the d-dimensional conformal group SO(d+1,1) up into multiplets of SO(d,1). This leads to an expansion of d-dimensional conformal blocks in terms of blocks in d-1 dimensions. In particular, we obtain a formula for 3d conformal blocks as an infinite sum over 2F1 hypergeometric functions with closed-form coefficients.

  8. Common blocks for ASQS(12

    Directory of Open Access Journals (Sweden)

    Lorenzo Milazzo

    1997-05-01

    Full Text Available An ASQS(v is a particular Steiner system featuring a set of v vertices and two separate families of blocks, B and G, whose elements have a respective cardinality of 4 and 6. It has the property that any three vertices of X belong either to a B-block or to a G-block. The parameter cb is the number of common blocks in two separate ASQSs, both defined on the same set of vertices X . In this paper it is shown that cb ≤ 29 for any pair of ASQSs(12.

  9. VARYING A V BLOCK COMPLICATING SNAKE BITE - A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Vikas

    2014-02-01

    Full Text Available Snake venom toxicities comprise mainly bleeding disorders and nephrotoxicity. Cardiotoxicity is a rare manifestation of snake bite. We describe the case of a previously healthy 23 - year - old man who developed coagulopathy and AV node dysfunction following snake bite. Electrocardiography showed all variatio ns of AV conduction dysfunction . This is the first account of AV node dysfu nction caused by a snake bite with cardiotoxi city presenting as atrioventricular block

  10. Eikonalization of Conformal Blocks

    CERN Document Server

    Fitzpatrick, A Liam; Walters, Matthew T; Wang, Junpu

    2015-01-01

    Classical field configurations such as the Coulomb potential and Schwarzschild solution are built from the $t$-channel exchange of many light degrees of freedom. We study the CFT analog of this phenomenon, which we term the `eikonalization' of conformal blocks. We show that when an operator $T$ appears in the OPE $\\mathcal{O}(x) \\mathcal{O}(0)$, then the large spin $\\ell$ Fock space states $[TT \\cdots T]_{\\ell}$ also appear in this OPE with a computable coefficient. The sum over the exchange of these Fock space states in an $\\langle \\mathcal{O} \\mathcal{O} \\mathcal{O} \\mathcal{O} \\rangle$ correlator build the classical `$T$ field' in the dual AdS description. In some limits the sum of all Fock space exchanges can be represented as the exponential of a single $T$ exchange in the 4-pt correlator of $\\mathcal{O}$. Our results should be useful for systematizing $1/\\ell$ perturbation theory in general CFTs and simplifying the computation of large spin OPE coefficients. As examples we obtain the leading $\\log \\ell$...

  11. Adductor Canal Block versus Femoral Nerve Block and Quadriceps Strength

    DEFF Research Database (Denmark)

    Jæger, Pia Therese; Nielsen, Zbigniew Jerzy Koscielniak; Henningsen, Lene Marianne;

    2013-01-01

    : The authors hypothesized that the adductor canal block (ACB), a predominant sensory blockade, reduces quadriceps strength compared with placebo (primary endpoint, area under the curve, 0.5-6 h), but less than the femoral nerve block (FNB; secondary endpoint). Other secondary endpoints were...

  12. 40 CFR 798.3260 - Chronic toxicity.

    Science.gov (United States)

    2010-07-01

    ....3260 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... period. Blood samples should be drawn for clinical chemistry measurements from all non-rodents and at... all animals, including those which died during the experiment or were killed in moribund...

  13. Developmental Toxicity Potential of Nitroguanidine in Rats

    Science.gov (United States)

    1988-02-01

    profile for nitroguanidine, related intermediates/by- products of its manufacture, and its environmental degradation products . The rat developmental toxicity...The vehicle for nitroguanidine was a 1% solution of carboxymethylcellulose sodium salt, high viscosity (Sigma Chemical Co., St. Louis, MO...Nitroguanidine is not soluble in water at the dose levels tested. Carboxymethylcellulose holds nitroguanidine in a homogeneous suspension and is not

  14. Predicting the toxicity of metal mixtures.

    Science.gov (United States)

    Balistrieri, Laurie S; Mebane, Christopher A

    2014-01-01

    The toxicity of single and multiple metal (Cd, Cu, Pb, and Zn) solutions to trout is predicted using an approach that combines calculations of: (1) solution speciation; (2) competition and accumulation of cations (H, Ca, Mg, Na, Cd, Cu, Pb, and Zn) on low abundance, high affinity and high abundance, low affinity biotic ligand sites; (3) a toxicity function that accounts for accumulation and potency of individual toxicants; and (4) biological response. The approach is evaluated by examining water composition from single metal toxicity tests of trout at 50% mortality, results of theoretical calculations of metal accumulation on fish gills and associated mortality for single, binary, ternary, and quaternary metal solutions, and predictions for a field site impacted by acid rock drainage. These evaluations indicate that toxicity of metal mixtures depends on the relative affinity and potency of toxicants for a given aquatic organism, suites of metals in the mixture, dissolved metal concentrations and ratios, and background solution composition (temperature, pH, and concentrations of major ions and dissolved organic carbon). A composite function that incorporates solution composition, affinity and competition of cations for two types of biotic ligand sites, and potencies of hydrogen and individual metals is proposed as a tool to evaluate potential toxicity of environmental solutions to trout.

  15. 40 CFR 799.9120 - TSCA acute dermal toxicity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true TSCA acute dermal toxicity. 799.9120 Section 799.9120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES...) Preparations. Healthy young adult animals are acclimatized to the laboratory conditions for at least 5...

  16. 40 CFR 799.9325 - TSCA 90-day dermal toxicity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true TSCA 90-day dermal toxicity. 799.9325 Section 799.9325 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES... healthy animals as soon as possible after weaning and acclimatization. (B) Dosing should generally...

  17. 40 CFR 799.9410 - TSCA chronic toxicity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true TSCA chronic toxicity. 799.9410 Section 799.9410 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES... healthy animals as soon as possible after weaning and acclimatization. (B) Dosing of rodents...

  18. 40 CFR 799.9346 - TSCA 90-day inhalation toxicity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true TSCA 90-day inhalation toxicity. 799.9346 Section 799.9346 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC.... Testing should be started with young healthy animals as soon as possible after weaning and...

  19. 40 CFR 799.9110 - TSCA acute oral toxicity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true TSCA acute oral toxicity. 799.9110 Section 799.9110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES... Part 792—Good Laboratory Practice Standards. (3) Test procedures—(i) Preparations. Healthy young...

  20. 40 CFR 799.9130 - TSCA acute inhalation toxicity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true TSCA acute inhalation toxicity. 799.9130 Section 799.9130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... 40 CFR part 792, subpart f. (3) Test procedures—(i) Preparation. Healthy young adult animals...

  1. 40 CFR 799.9370 - TSCA prenatal developmental toxicity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true TSCA prenatal developmental toxicity. 799.9370 Section 799.9370 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... control shall be used. Healthy animals shall be randomly assigned to the control and treatment groups,...

  2. Refrigerants and heat carrier fluids on a betain basis. A natural solution for preventing environmental, toxicity and corrosion problems in heating and cooling systems; Kaelte- und Waermetraeger auf Betain-Basis. Natuerliche Loesung fuer Umwelt-, Toxizitaets- und Korrosionsprobleme in Heiz- und Kuehlsystemen

    Energy Technology Data Exchange (ETDEWEB)

    Willems, B.P.M.; Jokinen, J.

    2004-05-01

    Toxic liquids and environmental hazards in buildings and industrial plants are accepted less than ever today. So far, technical problems prevented substitution of glycol-based heat carrier fluids by brines or vegetable oils. A new refrigerant on the basis of betain has overcome these problems. (orig.) [German] Fluessigkeitstoxizitaet und Umweltrisiken in Gebaeuden und Industrieanlagen werden immer weniger akzeptiert. Der Ersatz Glykol-basierter Waermetraeger durch Fluessigkeiten auf Salz-Basis oder durch Pflanzenoel scheiterte bislang an technischen Schwierigkeiten. Ein neuerer Kaeltetraeger auf Betain-Basis hat diese Probleme ueberwunden. (orig.)

  3. Block Transfer Agreement Evaluation Project

    Science.gov (United States)

    Bastedo, Helena

    2010-01-01

    The objective of this project is to evaluate for the British Columbia Council on Admissions and Transfer (BCCAT) the effectiveness of block transfer agreements (BTAs) in the BC Transfer System and recommend steps to be taken to improve their effectiveness. Findings of this study revealed that institutions want to expand block credit transfer;…

  4. Four-block beam collimator

    CERN Multimedia

    1977-01-01

    The photo shows a four-block collimator installed on a control table for positioning the alignment reference marks. Designed for use with the secondary beams, the collimators operated in vacuum conditions. The blocks were made of steel and had a standard length of 1 m. The maximum aperture had a square coss-section of 144 cm2. (See Annual Report 1976.)

  5. OPAL Various Lead Glass Blocks

    CERN Multimedia

    These lead glass blocks were part of a CERN detector called OPAL (one of the four experiments at the LEP particle detector). OPAL uses some 12 000 blocks of glass like this to measure particle energies in the electromagnetic calorimeter. This detector measured the energy deposited when electrons and photons were slowed down and stopped.

  6. Block storage subsystem performance analysis

    CERN Document Server

    CERN. Geneva

    2016-01-01

    You feel that your service is slow because of the storage subsystem? But there are too many abstraction layers between your software and the raw block device for you to debug all this pile... Let's dive on the platters and check out how the block storage sees your I/Os! We can even figure out what those patterns are meaning.

  7. Postnatal toxic and acquired disorders.

    Science.gov (United States)

    Saint-Amour, Dave; Dallaire, Renee; Dulac, Oliver

    2013-01-01

    To develop and function optimally, the brain requires a balanced environment of electrolytes, amino acids, neurotransmitters, and metabolic substrates. As a consequence, organ dysfunction has the potential to induce brain disorders and toxic-metabolic encephalopathies, particularly when occurring during early stages of cerebral maturation. Induced toxicity of three different organ systems that are commonly associated with brain complications are discussed. First, thyroid hormone deficiency caused by intrinsic or extrinsic factors (e.g., environmental toxins) may induce severe adverse effects on child neurological development from reversible impairments to permanent mental retardation. Second, inadequate removal of wastes due to chronic renal failure leads to the accumulation of endogenous toxins that are harmful to brain function. In uremic pediatric patients, the brain becomes more vulnerable to exogenous substances such as aluminum, which can induce aluminum encephalopathy. Following surgical procedures, neurological troubles including focal defects and severe epileptic seizures may result from hypertensive encephalopathy combined with toxicity of immunomodulating substances, or from the delayed consequences of cardiovascular defect. Taken together, this illustrates that organ disorders clearly have an impact on child brain function in various ways.

  8. Streptococcal toxic shock syndrome

    OpenAIRE

    Gvozdenović Ljiljana; Pasternak Janko; Milovanović Stanislav; Ivanov Dejan; Milić Saša

    2010-01-01

    Introduction. Streptococcal toxic shock syndrome is now recognized as a toxin-mediated, multisystem illness. It is characterized by an early onset of shock with multiorgan failure and continues to be associated with high morbidity and mortality, caused by group A Streptococcus pyogenes. The symptoms for staphylococcal and streptococcal toxic shock syndrome are similar. Streptococcal toxic shock syndrome was not well described until 1993, when children who had suffered from varicella pre...

  9. Developing Key Parameters for Green Performance of Partition Wall Blocks

    Directory of Open Access Journals (Sweden)

    Goh Cheng Siew

    2016-01-01

    Full Text Available To promote sustainable construction, it is important to consider green performance of construction materials throughout the life cycle. Selecting inappropriate materials could not only affect the functional performance but also preclude the achievement of green building performance as a whole. Green performance of construction materials has therefore been one of the primary considerations of green building assessment systems. Using partition wall blocks as an example, this paper examines green performance of building materials primarily from the cradle to gate boundaries. Nine key parameters are proposed for the green performance of partition wall blocks. Apart from environmental features, technical performance of partition wall blocks is also taken into consideration since it is the determinant of the lifecycle performance. This paper offers a roadmap to decision makers to make environmentally responsible choices for their materials of internal walls and partitions, and hence provides a potential sustainable solution for green buildings.

  10. CHEMICAL TOXICITY OF URANIUM

    Directory of Open Access Journals (Sweden)

    Sermin Cam

    2007-06-01

    Full Text Available Uranium, occurs naturally in the earth’s crust, is an alpha emitter radioactive element from the actinide group. For this reason, U-235 and U-238, are uranium isotopes with long half lives, have got radiological toxicity. But, for natural-isotopic-composition uranium (NatU, there is greater risk from chemical toxicity than radiological toxicity. When uranium is get into the body with anyway, also its chemical toxicity must be thought. [TAF Prev Med Bull 2007; 6(3.000: 215-220

  11. EnviroAtlas - Green Bay, WI - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Green Bay, WI EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  12. Convulsion due to levobupivacaine in axillary brachial plexus block: Case report

    Directory of Open Access Journals (Sweden)

    Cevdet Düger

    2013-06-01

    Full Text Available Axillary brachial plexus block is an effective method of anaesthesia for the surgeries performed on the hand, forearm and distal third of the arm. However it has the risk of serious complications such as cardiovascular and central nervous system toxicity. Levobupivacaine is a long acting amide local anaesthetic used for epidural, caudal, spinal, infiltration and peripheral nerve blocks. Levobupivacaine is the S (- isomer of racemic bupivacaine and has a lower risk of cardiovascular, central nervous system toxicity than bupivacaine. However central system toxicity cases due to absorption of the drug into the systemic circulation has been reported. Here, we report a case having no vascular puncture during axillary brachial plexus block performance but developing convulsion due to levobupivacain after the intervention.

  13. A comparison of standard acute toxicity tests with rapid-screening toxicity tests

    Energy Technology Data Exchange (ETDEWEB)

    Toussaint, M.W. [Geo-Centers, Inc., Fort Washington, MD (United States); Shedd, T.R. [Army Biomedical Research and Development Lab., Frederick, MD (United States); Schalie, W.H. van der [Environmental Protection Agency, Washington, DC (United States); Leather, G.R. [Hood Coll., Frederick, MD (United States). Dept. of Biology

    1995-05-01

    This study compared the relative sensitivity of five inexpensive, rapid toxicity tests to the sensitivity of five standard aquatic acute toxicity tests through literature review and testing. The rapid toxicity tests utilized organisms that require little culturing or handling prior to testing: a freshwater rotifer (Branchionus calyciflorus); brine shrimp (Artemia salina); lettuce (Lactuca sativa); and two microbial tests (Photobacterium phosphoreum--Microtox{reg_sign} test, and a mixture of bacterial species--the Polytox{reg_sign} test). Standard acute toxicity test species included water fleas (Daphnia magna and Ceriodaphnia dubia), green algae (Selenastrum capricornutum), fathead minnows (Pimephales promelas), and mysid shrimp (Mysidopsis bahia). Sensitivity comparisons between rapid and standard acute toxicity tests were based on LC50/EC50 data from 11 test chemicals. Individually, the lettuce and rotifer tests ranked most similar in sensitivity to the standard tests, while Microtox fell just outside the range of sensitivities represented by the group of standard acute toxicity tests. The brine shrimp and Polytox tests were one or more orders of magnitude different from the standard acute toxicity tests for most compounds. The lettuce, rotifer, and Microtox tests could be used as a battery for preliminary toxicity screening of chemicals. Further evaluation of complex real-world environmental samples is recommended.

  14. Comparison of standard acute toxicity tests with rapid-screening toxicity tests

    Energy Technology Data Exchange (ETDEWEB)

    Toussaint, M.W.; Shedd, T.R.; VanDerSchal, W.H.; Leather, G.R.

    1995-10-01

    This study compared the relative sensitivity of five inexpensive, rapid toxicity tests to the sensitivity of five standard aquatic acute toxicity tests through literature review and testing. The rapid toxicity tests utilized organisms that require little culturing or handling prior to testing: a freshwater rotifer (Branchionus ccalyciflorus); brine shrimp (Artemia salina); lettuce (Lactuca sativa); and two microbial tests (Photo bacterium phosphoreum - Microtox test, and a mixture of bacterial species - the polytox test). Standard acute toxicity test species included water fleas (Daphnia magna and Ceriadaphnta dubia), green algae (Setenastrum capricarnutum), fathead minnows (Pimephalespromelas), and mysid shrimp (Mysidopsis bahia). Sensitivity comparisons between rapid and standard acute toxicity tests were based on LC5O/EC50 data from 11 test chemicals. Individually, the lettuce and rotifer tests ranked most similar in sensitivity to the standard tests, while Microtox fell just outside the range of sensitivities represented by the group of standard acute toxicity tests. The brine shrimp and Polytox tests were one or more orders of magnitude different from the standard acute toxicity tests for most compounds. The lettuce, rotifer, and Microtox tests could be used as a battery for preliminary toxicity screening of chemicals. Further evaluation of complex real-world environmental samples is recommended.

  15. Conformal Nets II: Conformal Blocks

    Science.gov (United States)

    Bartels, Arthur; Douglas, Christopher L.; Henriques, André

    2017-03-01

    Conformal nets provide a mathematical formalism for conformal field theory. Associated to a conformal net with finite index, we give a construction of the `bundle of conformal blocks', a representation of the mapping class groupoid of closed topological surfaces into the category of finite-dimensional projective Hilbert spaces. We also construct infinite-dimensional spaces of conformal blocks for topological surfaces with smooth boundary. We prove that the conformal blocks satisfy a factorization formula for gluing surfaces along circles, and an analogous formula for gluing surfaces along intervals. We use this interval factorization property to give a new proof of the modularity of the category of representations of a conformal net.

  16. Progresses on induction of toxicity on longevity by environmental exposure and the related toxicology in nematode Caenorhabditis elegans%环境暴露致秀丽线虫衰老毒性及相关作用机制研究进展

    Institute of Scientific and Technical Information of China (English)

    武秋立; 王大勇

    2011-01-01

    衰老作为一个重要的评价终点,目前已经广泛应用于秀丽线虫环境暴露评价以及相关毒理学研究.系统总结了各种金属以及有机污染物暴露所致秀丽线虫衰老毒性;分析了胰岛素信号、应激反应与氧化应激、线粒体呼吸链、金属硫蛋白、金属诱导胁迫响应蛋白NUMR-1和NUMR-2等在环境暴露致秀丽线虫衰老毒性形成中的重要调控功能;指出了代谢变化与环境暴露致秀丽线虫衰老毒性形成之间存在的密切关联;讨论了基于环境暴露致秀丽线虫衰老毒性及相应毒作用机制研究中尚存在的问题以及可能的解决策略.%In model animal of Caenorhabditis elegans,aging has gradually become a widely used endpoint for e-valuation of environmental safety and toxicology. In this review, the induction of toxicity on longevity by different metals and organic pollutants in Caenorhabditis elegans was first summarized; Moreover, we discussed the important rales of insulin signals,stress response and oxidative stress,mitochondria respiratory chain, metallothioneins and metal responsive protein (NUMR-1, NUMR-2) in regulating the formation of toxicity on longevity induced by environmental exposure,as well as the possible association of metabolism with toxicity on longevity. Furthermore,the questions needed to be solved for further studies on evaluation of toxicity on longevity induced by environmental exposure and the related toxicology have been discussed,and the related suggestions have also been provided.

  17. Identification of Chemicals of Interest to the Department of Defense and U.S. Air Force Among the U.S. Environmental Protection Agency’s Integrated Risk Information System Chemicals that are Due for Reassessment of their Toxicity Values

    Science.gov (United States)

    2010-03-16

    10-087, 16 March 2010 LIST OF ACRONYMS ATSDR Agency for Toxic Substances and Disease Registry CASRN Chemical Abstract Services Registry Number...included 473 chemicals with Chemical Abstract Services Registry Numbers (CASRNs) that are evaluated in this report (additional detail in Appendix A). The... Chemical Abstract Services Registry Numbers (CASRNs): 2,4-/2,6- dinitrotoluene mixture; refractory ceramic fibers; uranium, soluble salts; nickel, soluble

  18. POTENTIAL DEVELOPMENTAL TOXICITY OF ANATOXIN-A, A CYANOBACTERIAL TOXIN

    Science.gov (United States)

    Anatoxin-a acts as a neuro-muscular blocking agent. Acute toxicity is characterized by rapid onset of paralysis, tremors, convulsions, and death. Human exposures may occur from recreational water activities and dietary supplements, but are primarily through drinking water. The...

  19. Pyridostigmine Synergistic Toxicity Study.

    Science.gov (United States)

    1995-05-31

    AND DEET IN THE LABORATORY RAT 1. Executive Sum m ary .............................................................................................. 2 2...TOXICOLOGICAL STUDY 75-48-2665 ACUTE ORAL TOXICITY STUDY OF PYRIDOSTIGMINE BROMIDE. PERMETHRIN. AND DEET IN THE LABORATORY RAT 1. REFERENCES: See Appendix A... LABORATORY RAT 1. PURPOSE: The purpose of this study was to determine potential toxic interactions when pyridostigmine bromide. permethrin. and DEET are given

  20. Toxic proteins in plants.

    Science.gov (United States)

    Dang, Liuyi; Van Damme, Els J M

    2015-09-01

    Plants have evolved to synthesize a variety of noxious compounds to cope with unfavorable circumstances, among which a large group of toxic proteins that play a critical role in plant defense against predators and microbes. Up to now, a wide range of harmful proteins have been discovered in different plants, including lectins, ribosome-inactivating proteins, protease inhibitors, ureases, arcelins, antimicrobial peptides and pore-forming toxins. To fulfill their role in plant defense, these proteins exhibit various degrees of toxicity towards animals, insects, bacteria or fungi. Numerous studies have been carried out to investigate the toxic effects and mode of action of these plant proteins in order to explore their possible applications. Indeed, because of their biological activities, toxic plant proteins are also considered as potentially useful tools in crop protection and in biomedical applications, such as cancer treatment. Genes encoding toxic plant proteins have been introduced into crop genomes using genetic engineering technology in order to increase the plant's resistance against pathogens and diseases. Despite the availability of ample information on toxic plant proteins, very few publications have attempted to summarize the research progress made during the last decades. This review focuses on the diversity of toxic plant proteins in view of their toxicity as well as their mode of action. Furthermore, an outlook towards the biological role(s) of these proteins and their potential applications is discussed.

  1. 环境激素烯菌酮引发小鼠前列腺癌细胞的毒性机制%Toxic Mechanism of Environmental Hormone Vinclozolin on Mouse Prostate Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    王娜; 钱红燕; 王迎; 周显青

    2012-01-01

    To study the toxic mechanism of environmental hormone vinclozolin on mouse prostate cancer (RM-1) cells,3 groups experiments were designed: control group,vinclozolin-treated group,and addition of vitamin E to vinckozolin-treated group (experimental group).After 48 h,morphological changes of the cells were observed.Cell proliferation rate,makmdialdehyde (MDA) content and the ability to inhibit hydroxyl radical were determined as well as the activities of lactate dehydrogenase (LDH),Na+ -K+ -ATPase and Ca2+ -Mg2+ -ATPase.Compared with control group,the number of RM-1 adherent cells,cell proliferation rate,the ability to inhibit hydroxyl radical,Na+ -K+-ATPase activity and Ca2+ -Mg2+ -ATPase activity significantly decreased (p <0.05),while LDH activity and MDA content obviously increased (p <0.05) in vinclozolin-treated group.After addition of vitamin E,compared with vinclozolin-treated group,the number of adherent cells,cell proliferation rate,the ability to inhibit the hydroxyl radical,Na+ -K+ -ATPase activity and Ca2 +-Mg2 +-ATPase activity (p <0.05) significantly increased,while LDH activity and MDA content obviously decreased (p <0.05).It was indicated that vitamin E antagonized the oxidative stress of RM-1 cells treated with vinclozo-lin.Thus,the damage of cell membrane was relieved and the integrity and function of cells were maintained,preventing the escape of intraceDuiar LDH and the decreasing Na+ -K+ -ATPase activity and Ca2 + -Mg2+ -ATPase activity.As a result,the cell death and cell proliferation rate decreased.%为探讨环境激素烯菌酮引发小鼠前列腺癌(RM-1)细胞毒性机制,设计了3组实验,分别为对照组、烯菌酮染毒组(染毒组)和烯菌酮染毒后添加维生素E组(实验组),各组给药培养48 h后,观察细胞形态变化.检测细胞增殖活性、丙二醛(MDA)含量、抑制羟自由基能力、乳酸脱氢酶(LDH)活性、Na+ -K+ -ATP酶活性和Ca2+ -Mg2 -ATP酶活性.结果表明,与对照组相比,染毒组RM-1

  2. MarineMineralsProgramBlocks

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains OCS block outlines and delineated polygons in ESRI ArcGIS shape file format for the BOEM Gulf of Mexico Region that contain sediment resources...

  3. Left bundle-branch block

    DEFF Research Database (Denmark)

    Risum, Niels; Strauss, David; Sogaard, Peter;

    2013-01-01

    The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...

  4. Mechanisms of Phosphine Toxicity

    Directory of Open Access Journals (Sweden)

    Nisa S. Nath

    2011-01-01

    Full Text Available Fumigation with phosphine gas is by far the most widely used treatment for the protection of stored grain against insect pests. The development of high-level resistance in insects now threatens its continued use. As there is no suitable chemical to replace phosphine, it is essential to understand the mechanisms of phosphine toxicity to increase the effectiveness of resistance management. Because phosphine is such a simple molecule (PH3, the chemistry of phosphorus is central to its toxicity. The elements above and below phosphorus in the periodic table are nitrogen (N and arsenic (As, which also produce toxic hydrides, namely, NH3 and AsH3. The three hydrides cause related symptoms and similar changes to cellular and organismal physiology, including disruption of the sympathetic nervous system, suppressed energy metabolism and toxic changes to the redox state of the cell. We propose that these three effects are interdependent contributors to phosphine toxicity.

  5. Mechanisms of phosphine toxicity.

    Science.gov (United States)

    Nath, Nisa S; Bhattacharya, Ishita; Tuck, Andrew G; Schlipalius, David I; Ebert, Paul R

    2011-01-01

    Fumigation with phosphine gas is by far the most widely used treatment for the protection of stored grain against insect pests. The development of high-level resistance in insects now threatens its continued use. As there is no suitable chemical to replace phosphine, it is essential to understand the mechanisms of phosphine toxicity to increase the effectiveness of resistance management. Because phosphine is such a simple molecule (PH(3)), the chemistry of phosphorus is central to its toxicity. The elements above and below phosphorus in the periodic table are nitrogen (N) and arsenic (As), which also produce toxic hydrides, namely, NH(3) and AsH(3). The three hydrides cause related symptoms and similar changes to cellular and organismal physiology, including disruption of the sympathetic nervous system, suppressed energy metabolism and toxic changes to the redox state of the cell. We propose that these three effects are interdependent contributors to phosphine toxicity.

  6. Mechanisms of Phosphine Toxicity

    Science.gov (United States)

    Nath, Nisa S.; Bhattacharya, Ishita; Tuck, Andrew G.; Schlipalius, David I.; Ebert, Paul R.

    2011-01-01

    Fumigation with phosphine gas is by far the most widely used treatment for the protection of stored grain against insect pests. The development of high-level resistance in insects now threatens its continued use. As there is no suitable chemical to replace phosphine, it is essential to understand the mechanisms of phosphine toxicity to increase the effectiveness of resistance management. Because phosphine is such a simple molecule (PH3), the chemistry of phosphorus is central to its toxicity. The elements above and below phosphorus in the periodic table are nitrogen (N) and arsenic (As), which also produce toxic hydrides, namely, NH3 and AsH3. The three hydrides cause related symptoms and similar changes to cellular and organismal physiology, including disruption of the sympathetic nervous system, suppressed energy metabolism and toxic changes to the redox state of the cell. We propose that these three effects are interdependent contributors to phosphine toxicity. PMID:21776261

  7. Multi-block and path modelling procedures

    DEFF Research Database (Denmark)

    Høskuldsson, Agnar

    2008-01-01

    The author has developed a unified theory of path and multi-block modelling of data. The data blocks are arranged in a directional path. Each data block can lead to one or more data blocks. It is assumed that there is given a collection of input data blocks. Each of them is supposed to describe one...

  8. NANOSTRUCTURES OF FUNCTIONAL BLOCK COPOLYMERS

    Institute of Scientific and Technical Information of China (English)

    Guojun Liu

    2000-01-01

    Nanostructure fabrication from block copolymers in my group normally involves polymer design, synthesis, selfassembly, selective domain crosslinking, and sometimes selective domain removal. Preparation of thin films with nanochannels was used to illustrate the strategy we took. In this particular case, a linear triblock copolymer polyisopreneblock-poly(2-cinnamoylethyl methacrylate)-block-poly(t-butyl acrylate), PI-b-PCEMA-b-PtBA, was used. Films, 25 to50μm thick, were prepared from casting on glass slides a toluene solution of PI-b-PCEMA-b-PtBA and PtBA homopolymer,hPtBA, where hPtBA is shorter than the PtBA block. At the hPtBA mass fraction of 20% relative to the triblock or the total PtBA (hPtBA and PtBA block) volume fraction of 0.44, hPtBA and PtBA formed a seemingly continuous phase in the matrix of PCEMA and PI. Such a block segregation pattern was locked in by photocrosslinking the PCEMA domain. Nanochannels were formed by extracting out hPtBA with solvent. Alternatively, larger channels were obtained from extracting out hPtBA and hydrolyzing the t-butyl groups of the PtBA block. Such membranes were not liquid permeable but had gas permeability constants ~6 orders of magnitude higher than that of low-density polyethylene films.

  9. Environmental Program

    Science.gov (United States)

    Fischer, Holger

    2009-01-01

    NASA's White Sands Test Facility has six core environmental compliance capabilities: remote hazardous testing of reactive, explosive and toxic materials and fluids; hypergolic fluids materials and systems testing; oxygen materials and system testing; hypervelocity impact testing; flight hardware processing; and, propulsion testing. The facility's permit status and challenges are reviewed. Historic operations and practices dating from the 1960s through the early 1980s resulted in contamination of the facility's groundwater. An environmental restoration effort has been employed to protect public health and the health of the workforce. The restoration seeks to properly handle hazardous materials and waste processes; determine the nature and extent of the contamination; stop the migration of contaminated groundwater; stabilize the plume front which has been assessed as the greatest risk to public health; and, clean-up the environment to restore it to preexisting conditions. The Plume Front Treatment System is operational and seeks to stop the westward movement of the plume to protect drinking water and irrigation well. Specifically, the treatment system will extract contaminated water from the aquifer, remove chemical using the best available technology, and return (inject) the treated water back to the aquifer. The Mid-Plume Interception Treatment System also seeks to stop the migration of containment, as well as to evaluate new technologies to accelerate cleanup, such as bioremediation.

  10. Environmental Health Disparities: A Framework Integrating Psychosocial and Environmental Concepts

    OpenAIRE

    Gee, Gilbert C.; Payne-Sturges, Devon C

    2004-01-01

    Although it is often acknowledged that social and environmental factors interact to produce racial and ethnic environmental health disparities, it is still unclear how this occurs. Despite continued controversy, the environmental justice movement has provided some insight by suggesting that disadvantaged communities face greater likelihood of exposure to ambient hazards. The exposure–disease paradigm has long suggested that differential “vulnerability” may modify the effects of toxicants on b...

  11. Skin delivery by block copolymer nanoparticles (block copolymer micelles).

    Science.gov (United States)

    Laredj-Bourezg, Faiza; Bolzinger, Marie-Alexandrine; Pelletier, Jocelyne; Valour, Jean-Pierre; Rovère, Marie-Rose; Smatti, Batoule; Chevalier, Yves

    2015-12-30

    Block copolymer nanoparticles often referred to as "block copolymer micelles" have been assessed as carriers for skin delivery of hydrophobic drugs. Such carriers are based on organic biocompatible and biodegradable materials loaded with hydrophobic drugs: poly(lactide)-block-poly(ethylene glycol) copolymer (PLA-b-PEG) nanoparticles that have a solid hydrophobic core made of glassy poly(d,l-lactide), and poly(caprolactone)-block-poly(ethylene glycol) copolymer (PCL-b-PEG) nanoparticles having a liquid core of polycaprolactone. In vitro skin absorption of all-trans retinol showed a large accumulation of retinol in stratum corneum from both block copolymer nanoparticles, higher by a factor 20 than Polysorbate 80 surfactant micelles and by a factor 80 than oil solution. Additionally, skin absorption from PLA-b-PEG nanoparticles was higher by one order of magnitude than PCL-b-PEG, although their sizes (65nm) and external surface (water-swollen PEG layer) were identical as revealed by detailed structural characterizations. Fluorescence microscopy of histological skin sections provided a non-destructive picture of the storage of Nile Red inside stratum corneum, epidermis and dermis. Though particle cores had a different physical states (solid or liquid as measured by (1)H NMR), the ability of nanoparticles for solubilization of the drug assessed from their Hildebrand solubility parameters appeared the parameter of best relevance regarding skin absorption.

  12. TOXICOGENOMIC STUDY OF TRIAZOLE FUNGICIDES AND PERFLUOROALKYL ACIDS IN RAT LIVERS ACCURATELY CATEGORIZES CHEMICALS AND IDENTIFIES MECHANISMS OF TOXICITY

    Science.gov (United States)

    Toxicogenomic analysis of five environmental chemicals was performed to investigate the ability of genomics to predict toxicity, categorize chemicals, and elucidate mechanisms of toxicity. Three triazole antifungals (myclobutanil, propiconazole, and triadimefon) and two perfluori...

  13. Species-specific differences in peroxisome proliferation, catalase, and SOD2 upregulation as well as toxicity in human, mouse, and rat hepatoma cells induced by the explosive and environmental pollutant 2,4,6-trinitrotoluene.

    Science.gov (United States)

    Naumenko, Ekaterina Anatolevna; Ahlemeyer, Barbara; Baumgart-Vogt, Eveline

    2017-03-01

    2,4,6-Trinitrotoluene (TNT) has been widely used as an explosive substance and its toxicity is still of interest as it persisted in polluted areas. TNT is metabolized in hepatocytes which are prone to its toxicity. Since analysis of the human liver or hepatocytes is restricted due to ethical reasons, we investigated the effects of TNT on cell viability, reactive oxygen species (ROS) production, peroxisome proliferation, and antioxidative enzymes in human (HepG2), mouse (Hepa 1-6), and rat (H4IIEC3) hepatoma cell lines. Under control conditions, hepatoma cells of all three species were highly comparable exhibiting identical proliferation rates and distribution of their cell cycle phases. However, we found strong differences in TNT toxicity with the lowest IC50 values (highest cell death rate) for rat cells, whereas human and mouse cells were three to sevenfold less sensitive. Moreover, a strong decrease in cellular dehydrogenase activity (MTT assay) and increased ROS levels were noted. TNT caused peroxisome proliferation with rat hepatoma cells being most responsive followed by those from mouse and human. Under control conditions, rat cells contained fivefold higher peroxisomal catalase and mitochondrial SOD2 activities and a twofold higher capacity to reduce MTT than human and mouse cells. TNT treatment caused an increase in catalase and SOD2 mRNA and protein levels in human and mouse, but not in rat cells. Similarly, human and mouse cells upregulated SOD2 activity, whereas rat cells failed therein. We conclude that TNT induced oxidative stress, peroxisome proliferation and mitochondrial damage which are highest in rat cells rendering them most susceptible toward TNT. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 989-1006, 2017.

  14. EnviroAtlas - New York City, NY - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 6,378 block groups in New York City, New York. The US...

  15. EnviroAtlas - Cleveland, OH - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 1,442 block groups in Cleveland, Ohio. The US EPA's...

  16. EnviroAtlas - Woodbine, IA - Historic Places by Census Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset portrays the total number of historic places located within each Census Block Group (CBG). The historic places data were compiled from the...

  17. EnviroAtlas - Durham, NC - Historic Places by Census Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset portrays the total number of historic places located within each Census Block Group (CBG). The historic places data were compiled from the...

  18. EnviroAtlas - Phoenix, AZ - Historic Places by Census Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset portrays the total number of historic places located within each Census Block Group (CBG). The historic places data were compiled from the...

  19. Social Vulnerability Index (SoVI) for Alabama based on 2000 Census Block Groups

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data depicts the social vulnerability of Alabama census block groups to environmental hazards. Data were culled primarily from the 2000 Decennial Census.

  20. Social Vulnerability Index (SoVI) for Alaska based on 2000 Census Block Groups

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data depicts the social vulnerability of Alaska census block groups to environmental hazards. Data were culled primarily from the 2000 Decennial Census.

  1. Social Vulnerability Index (SoVI) for Illinois based on 2000 Census Block Groups

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data depicts the social vulnerability of Illinois census block groups to environmental hazards. Data were culled primarily from the 2000 Decennial Census.

  2. Social Vulnerability Index (SoVI) for Maryland based on 2000 Census Block Groups

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data depicts the social vulnerability of Maryland census block groups to environmental hazards. Data were culled primarily from the 2000 Decennial Census.

  3. EnviroAtlas - Fresno, CA - Historic Places by Census Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset portrays the total number of historic places located within each Census Block Group (CBG). The historic places data were compiled from the...

  4. EnviroAtlas - Tampa, FL - Historic Places by Census Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset portrays the total number of historic places located within each Census Block Group (CBG). The historic places data were compiled from the...

  5. EnviroAtlas - Pittsburgh, PA - Historic Places by Census Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset portrays the total number of historic places located within each Census Block Group (CBG). The historic places data were compiled from the...

  6. EnviroAtlas - Fresno, CA - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 405 block groups in Fresno, California. The US EPA's...

  7. EnviroAtlas - Durham, NC - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 193 block groups in Durham, North Carolina. The US...

  8. EnviroAtlas - New Bedford, MA - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, green space, and wetlands. Forest is a combination of...

  9. EnviroAtlas - Paterson, NJ - Greenspace Around Schools by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas data set shows the number of schools in each block group in the EnviroAtlas community boundary as well as the number of schools where less than 25%...

  10. EnviroAtlas - Austin, TX - Greenspace Around Schools by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas data set shows the number of schools in each block group in the EnviroAtlas community boundary as well as the number of schools where less than 25%...

  11. EnviroAtlas - Minneapolis/St. Paul, MN - Land Cover by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, green space, agriculture, and wetlands. In this...

  12. EnviroAtlas - Memphis, TN - Greenspace Around Schools by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas data set shows the number of schools in each block group in the EnviroAtlas community boundary as well as the number of schools where less than 25%...

  13. EnviroAtlas - Austin, TX - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 750 block groups in Austin, Texas. The US EPA's...

  14. EnviroAtlas - Portland, OR - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 1176 block groups in Portland, Oregon. The US EPA's...

  15. EnviroAtlas - Portland, ME - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 146 block groups in Portland, Maine. The US EPA's...

  16. EnviroAtlas - Memphis, TN - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 703 block groups in Memphis, Tennessee. The US EPA's...

  17. EnviroAtlas - Minneapolis/St. Paul, MN - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 1,772 block groups in Minneapolis/St. Paul, Minnesota....

  18. EnviroAtlas - Woodbine, IA - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 1 block group in Woodbine, Iowa. The US EPA's...

  19. EnviroAtlas - Paterson, NJ - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 107 block groups in Paterson, New Jersey. The US EPA's...

  20. EnviroAtlas - Pittsburgh, PA - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 1,089 block groups in Pittsburgh, PA. The US EPA's...