WorldWideScience

Sample records for 60-hz exposure effects

  1. Effects of 60 Hz electromagnetic field exposure on testicular germ cell apoptosis in mice

    Institute of Scientific and Technical Information of China (English)

    JinSangLee; SangSeokAhn; KyeongCheonJung; Yoon-WonKim; SangKonLee

    2004-01-01

    Aim:To evaluate the effects of 60 Hz extremely low frequency (ELF) elelctromagnetic field (EMF) exposure on germ cell apoptosis in the testis of mice.Methods:Adult male BALB/c mice (7 weeks of age) were exposed to a 60 Hz EMF of 0.1 mT or 0.5 mT for 24 h/day.A sham-exposed group served as the control.After 8 weeks of exposure,the mice were sacrificed.Germ cell apoptosis in the testis was assessed by histopathological examination,the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL) and flow cytometric examination of isolated spermatogenic cells stained with 7 aminoactinomycin D (7-AAD).Results:EMF exposure did not significantly affect the body and testis weights,but significantly increased the incidence of germ cell death.The distinguishing morphological feature of EMF exposure was a decrement in the number of well organized seminiferous tubules.Quantitative analysis of TUNEL-positive germ cells showed a significantly higher apoptotic rate in the 0.5 mT exposed mice than that in the sham controls (P<0.05),while the difference between the two exposed groups was insignificant.The TUNEL-positive cells were mainly spermatogonia.In flow cytometryanalysis,the percentage of live cells [forward scatter count (FSC)hgh7-AAD-] was lower in the exposed groups than that in the controls (Figure 5A),but the decrease in viability was not statistically significant.Conclusion:Continuousexposure to ELF EMF may induce testicular germ cell apoptosis in mice.(Asian J Androl 2004 Mar;6:29-34)

  2. Effect of chronic 60-Hz electric field exposure on mammary tumorigenesis in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, L.E.; Leung, F.C.; Rommereim, D.N.; Buschbom, R.L.; Wilson, B.W.; Stevens, R.G.

    1989-07-01

    Female rats were administered a single dosage of 7 or 10 mg of DMBA intragastrically between 50 and 55 days of age and palpated weekly for mammary tumors in two experiments. Rats were either exposed to a 40 kV/m 60-Hz electric field or sham-exposed in utero through 18 or 23 weeks of age. There was no difference between electric field exposed and sham-exposed in incidence of first tumor. When the results of the two experiments were combined, the electric field exposed groups had significantly more tumors per tumor-bearing animal than the sham-groups. These results may have implications for the role of electric power use in the etiology and promotion of breast cancer. 21 refs., 1 fig., 1 tab.

  3. Effects of 60 Hz Magnetic Field Exposure on the Pineal and Hypothalamic-Pituitary-Gonadal Axis in the Siberian Hamster (Phodopus Sungorus)

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Bary W.(BATTELLE (PACIFIC NW LAB)); Matt, Kathleen S.(Arizona State University); Morris, James E.(BATTELLE (PACIFIC NW LAB)); Sasser, Lyle B.(BATTELLE (PACIFIC NW LAB)); Miller, Douglas L.(BATTELLE (PACIFIC NW LAB)); Anderson, Larry E.(BATTELLE (PACIFIC NW LAB))

    1999-11-15

    Experiments using the dwarf Siberian hamster Phodopus sungorus were carried out to determine possible neuroendocrine consequences of one-time and repeated exposures to 60 Hz magnetic fields (MF). Animals were maintained in either a short-light (SL, 8 h light:16 h dar) or long-light (LL, 16 h light:8h dark) photoperiod.

  4. The effect of extremely low-frequency magnetic field (50–60 Hz) exposure on spontaneous apoptosis: The results of a meta-analysis

    Science.gov (United States)

    Mansourian, Mahsa; Marateb, Hamid Reza; Vaseghi, Golnaz

    2016-01-01

    Background: This paper is a meta-analysis of the published data from in vitro studies to evaluate whether spontaneous apoptosis might be influenced by extremely low frequency (ELF) magnetic fields (MFs). Materials and Methods: A comprehensive scientific literature search in electronic databases was conducted and studies covering the period 2000–2010 were selected. Then, published studies involving the desired topic were retrieved. The inclusion criteria were percentage of apoptosis in the cells exposed to 50–60 Hz ELF-MFs. The statistical analysis was performed by comprehensive meta-analysis version 2. Results: The summary measure of association (95% confidence interval) for all 18 effect estimated from 8 studies was 1.18 (1.15, 1.20). Heterogeneity among studies was found. There was no evidence of publication bias for the association between exposure to MF and apoptosis risk. Conclusion: Our meta-analysis provided conclusive data that ELF-MFs can increase apoptosis in cancer and normal cells. Furthermore, there is a possibly individual intensity and time range with maximum created effect according to window effect.

  5. Human exposure to a 60 Hz, 1800 micro tesla magnetic field: a neuro behavioral study

    International Nuclear Information System (INIS)

    The effects of time-varying magnetic fields (MF) on humans have been actively investigated for the past three decades. One important unanswered question that scientists continue to investigate is the potential for MF exposure to have acute effects on human biology. Different strategies have been used to tackle this question using various physiological, neuro-physiological and behavioral indicators. For example, researchers investigating electro-encephalography (EEG) have reported that Extremely Low Frequency (ELF, < 300 Hz) MF can increase the resting occipital alpha rhythm (8-12 Hz) [1, 2]. Interestingly, other studies have demonstrated that human motor behavior can be modulated by ELF MF exposure, reporting that such an exposure can reduce anteroposterior standing balance oscillations [3, 4] or decrease physiological tremor intensity [5]. However, the main limitation in this domain is the difficulty of reproducing the results. A possible reason for this is the large variety of experimental approaches employed. Therefore, the aim of this project is to investigate the effects of a 60 Hz, 1800 μT MF exposure on physiological (i.e. heart rate and peripheral blood perfusion), neuro-physiological (brain electrical activity), and behavioral (postural oscillations, voluntary motor functions, and physiological tremor) aspects in humans using a single experimental procedure.Though the results from this study suggest a subtle reduction of human standing balance as well as a subtle increase of physiological tremor amplitude with MF exposure, no effect appeared on other investigated parameters, suggesting that one hour of 60 Hz, 1800 μT MF exposure may modulate human involuntary motor control without being detected in the electrical activity of the brain. (authors)

  6. Effects of 60-Hz fields, estradiol and xenoestrogens on human breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Dees, C.; Travis, C. [Oak Ridge National Lab., TN (United States); Garrett, S. [Oak Ridge Institute for Science and Education, Oak Ridge, TN (United States); Henley, D. [Univ. of Tennessee, Knoxville (United States)

    1996-10-01

    If exposure to xenoestrogens or electromagnetic fields (EMFs) such as 60 Hz contributes to the etiology of breast cancer, it is likely that they must stimulate the growth of breast cells, damage genetic material or enhance the effects of other mitogenic or mutagenic agents (co-promotion). Therefore, the ability of xenoestrogens or exposure to 60-Hz fields to stimulate the entry of growth-arrested human breast cancer cells into the cell cycle was determined using cyclin-dependent kinase 2 (Cdk2) activity, synthesis of cyclin D1 and cdc2 activity. Exposure of estrogen receptor-positive MCF-7 or T-47D cells to estrogen and xenoestrogens (DDT and Red No.3) increased Cdk2 and cyclin B1-cdc2 activity and cyclin D1 synthesis. Exposure of breast cancer cells to 12 mG or 1 or 9 G electromagnetic fields at 60 Hz failed to stimulate Cdk2 or cyclin B1-cdc2 activity or cyclin D1 synthesis. Simultaneous co-exposure of cells to 60-Hz fields and chemical promoters did not enhance Cdk2 activation above the levels produced by the chemical promoter alone. Estrogen and xenoestrogens also stimulated binding of the estrogen receptor to the estrogen receptor element but the EMF did not. Phorbol 12-myristate 13-acetate (PMA) induced phosphorylation of p53 and pRb105 in MCF-7 cells, but EMF exposure had no effect. DNA-damaging chemotherapeutic agents and Red Dye No. 3 were found to increase p53 site-specific DNA binding in breast cancer cells, but EMF exposure did not. These studies suggest that estrogen and xenoestrogens stimulate growth-arrested breast cancer cells to enter the growth cycle, but EMF exposure does not. Site-specific p53-DNA binding was increased in MCF-7 cells treated with DNA-damaging agents, but not by EMF exposure. EMF exposure does not appear to act as a promoter or DNA-damaging agent for human breast cancer cells in vitro. 34 refs., 10 figs.

  7. The effect of extremely low-frequency magnetic field (50–60 Hz exposure on spontaneous apoptosis: The results of a meta-analysis

    Directory of Open Access Journals (Sweden)

    Mahsa Mansourian

    2016-01-01

    Conclusion: Our meta-analysis provided conclusive data that ELF-MFs can increase apoptosis in cancer and normal cells. Furthermore, there is a possibly individual intensity and time range with maximum created effect according to window effect.

  8. Effects of a 60 Hz magnetic field on central cholinergic systems of the rat

    Energy Technology Data Exchange (ETDEWEB)

    Lai, H.; Carino, M.A.; Horita, A.; Guy, A.W. (Univ. of Washington, Seattle (United States))

    1993-03-15

    The authors studied the effects of an acute exposure to a 60 Hz magnetic field on sodium-dependent, high-affinity choline uptake in the brain of the rat. Decreases in uptake were observed in the frontal cortex and hippocampus after the animals were exposed to a magnetic field at flux densities [>=] 0.75 mT. These effects of the magnetic field were blocked by pretreating the animals with the narcotic antagonist naltrexone, but not by the peripheral opioid antagonist, naloxone methiodide. These data indicate that the magnetic-field-induced decreases in high-affinity choline uptake in the rat brain were mediated by endogenous opioids in the central nervous systems.

  9. Human exposure to a 60 Hz, 1800 micro tesla magnetic field: a neuro behavioral study; Exposition humaine a un champ magnetique de 1 800 microtesla a 60 Hz: une etude neurocomportementale

    Energy Technology Data Exchange (ETDEWEB)

    Legros, A.; Corbacio, M.; Prato, F.S.; Thomas, A.W. [Lawson Health Research Institute and University of Western Ontario, St Joseph Health' s Care (Canada); Beuter, A. [Laboratoire IMS Institut de Polytechnique de Bordeaux, Universite de Bordeaux, 33 (France); Goulet, D. [Hydro-Quebec TransEnergie, Montreal (Canada); Lambrozo, J.; Souques, M. [Electricite de France, Service des Etudes Medicales, 75 - Paris (France); Plante, M. [Hydro-Quebec, Direction Sante et securite, Montreal (Canada)

    2010-05-15

    The effects of time-varying magnetic fields (MF) on humans have been actively investigated for the past three decades. One important unanswered question that scientists continue to investigate is the potential for MF exposure to have acute effects on human biology. Different strategies have been used to tackle this question using various physiological, neuro-physiological and behavioral indicators. For example, researchers investigating electro-encephalography (EEG) have reported that Extremely Low Frequency (ELF, < 300 Hz) MF can increase the resting occipital alpha rhythm (8-12 Hz) [1, 2]. Interestingly, other studies have demonstrated that human motor behavior can be modulated by ELF MF exposure, reporting that such an exposure can reduce anteroposterior standing balance oscillations [3, 4] or decrease physiological tremor intensity [5]. However, the main limitation in this domain is the difficulty of reproducing the results. A possible reason for this is the large variety of experimental approaches employed. Therefore, the aim of this project is to investigate the effects of a 60 Hz, 1800 muT MF exposure on physiological (i.e. heart rate and peripheral blood perfusion), neuro-physiological (brain electrical activity), and behavioral (postural oscillations, voluntary motor functions, and physiological tremor) aspects in humans using a single experimental procedure.Though the results from this study suggest a subtle reduction of human standing balance as well as a subtle increase of physiological tremor amplitude with MF exposure, no effect appeared on other investigated parameters, suggesting that one hour of 60 Hz, 1800 muT MF exposure may modulate human involuntary motor control without being detected in the electrical activity of the brain. (authors)

  10. Regularly scheduled, day-time, slow-onset 60 Hz electric and magnetic field exposure does not depress serum melatonin concentration in nonhuman primates

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, W.R.; Smith, H.D.; Orr, J.L. [Southwest Research Inst., San Antonio, TX (United States); Reiter, R.J.; Barlow-Walden, L. [Univ. of Texas Health Science Center, San Antonio, TX (United States)

    1995-12-31

    Experiments conducted with laboratory rodents indicate that exposure to 60 Hz electric fields or magnetic fields can suppress nocturnal melatonin concentrations in pineal gland and blood. In three experiments employing three field-exposed and three sham-exposed nonhuman primates, each implanted with an indwelling venous cannula to allow repeated blood sampling, the authors studied the effects of either 6 kV/m and 50 {micro}T (0.5 G) or 30 kV/m and 100 {micro}T (1.0 G) on serum melatonin patterns. The fields were ramped on and off slowly, so that no transients occurred. Extensive quality control for the melatonin assay, computerized control and monitoring of field intensities, and consistent exposure protocols were used. No changes in nocturnal serum melatonin concentration resulted from 6 weeks of day-time exposure with slow field onset/offset and a highly regular exposure protocol. These results indicate that, under the conditions tested, day-time exposure to 60 Hz electric and magnetic fields in combination does not result in melatonin suppression in primates.

  11. Rapid-onset/offset, variably scheduled 60 Hz electric and magnetic field exposure reduces nocturnal serum melatonin concentration in nonhuman primates

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, W.R.; Smith, H.D. [Southwest Research Inst., San Antonio, TX (United States). Dept. of Biosciences and Bioengineering; Reiter, R.J.; Barlow-Walden, L. [Univ. of Texas Health Science Center, San Antonio, TX (United States). Dept. of Cellular and Structural Biology

    1995-12-31

    Experiments with rodents indicate that power-frequency electric field (EF) or magnetic field (MF) exposure can suppress the normal nocturnal increase in melatonin concentration in pineal gland and blood. In a separate set of three experiments conducted with nonhuman primates, the authors did not observe melatonin suppression as a result of 6 weeks of day-time exposure to combined 60 Hz electric and magnetic fields (E/MF) with regularly schedule ``slow`` E/MF onsets/offsets. The study described here used a different exposure paradigm in which two baboons were exposed to E/MF with ``rapid`` E/MF onsets/offsets accompanied by EF transients not found with slowly ramped E/MF onset/offset; profound reductions in nocturnal serum melatonin concentration were observed in this experiment. If replicated in a more extensive experiment, the observation of melatonin suppression only in the presence of E/MF transients would suggest that very specific exposure parameters determine the effects of 60 Hz E/MF on melatonin.

  12. Analysis of the effect of a 60 Hz AC field on histamine release by rat peritoneal mast cells.

    Science.gov (United States)

    Price, J A; Strattan, R D

    1998-01-01

    Reports have indicated effects of electromagnetic fields on inflammatory processes in vivo. To begin a systematic approach toward separating and examining the many components of such responses, we created and tested a temperature-controlled device to develop 5 mT 60 Hz magnetic fields for studies of the effects of fields on mast cells, a key component in acute inflammatory responses. Such fields have been reported to modulate cell activity, including changes in membrane function, in various systems. The magnetic field was generated using a solenoid and calibrated with an induction probe. Tests of mast cell function were determined by histamine release response to stimulation by compound 48/80, using both an "expose then test" and a "test during exposure" protocol. Aliquots not treated with 48/80 were used to evaluate field treatment effects on spontaneous histamine release. Freshly harvested rat peritoneal mast cells were exposed to the magnetic field for periods of 30 min to 2 h at 37 degrees C. They showed no significant degranulation during treatment, nor did they show reduced sensitivity to the degranulating agent 48/80. These observations are consistent with a model in which such processes are exclusively reflexive by the cells using field-independent membrane systems. This observation is very useful and was needed before examining longer term exposures in which gene expression in the cells might be influenced; this is the first such report of in vitro exposure of purified mast cells under these conditions and will further the study of the effects of electromagnetic fields on cell types active in acute inflammation.

  13. Biological effects of electric and magnetic fields with a 50/60 Hz frequency; Effets biologiques des champs electriques et magnetiques de frequence 50/60 Hz

    Energy Technology Data Exchange (ETDEWEB)

    Lambrozo, J. [Electricite de France (EDF), 75 - Paris (France)

    1997-05-01

    The question of the possible biological effects of electric and magnetic fields with a low frequency was raised in the 1970`s after the publication of Korobsova`s paper and the epidemiologic study of Wertheimer. It has generated an important research work in various scientific domains from the molecular biology to the epidemiology and the human experiments. This short paper takes stock of the results obtained so far. (J.S.)

  14. Possíveis efeitos adversos dos campos eletromagnéticos (50/60 Hz em humanos e em animais Potential adverse effects of electromagnetic fields (50/60 Hz on humans and animals

    Directory of Open Access Journals (Sweden)

    Caroline Wanderley Souto Ferreira Anselmo

    2005-12-01

    Full Text Available Os avanços tecnológicos têm aumentado o número de equipamentos elétricos e eletrônicos, seja nas residências ou mesmo no ambiente de trabalho, fazendo com que a população conviva com grande número de fontes de irradiação eletromagnética, com os mais diversos níveis de potência e freqüência. Por muitos anos, alguns cientistas e engenheiros acreditaram que o campo eletromagnético (CEM com freqüência extremamente baixa não pudesse causar efeitos e alterações significantes no material biológico. O objetivo deste trabalho é verificar os possíveis efeitos adversos dos CEMs em humanos e animais, que foram publicados nos últimos anos, através de uma revisão da literatura disponível em Medline, revistas nacionais e internacionais e catálogos de obras de referência na área dos CEM (50/60 Hz. Como resultado foi observado que o CEM (50/60 Hz é capaz de produzir diversos efeitos adversos em humanos e animais, como por exemplo: distúrbios na reprodução, doenças degenerativas, efeitos psiquiátricos e psicológicos, alterações citogenéticas, alterações no sistema cardiovascular, nervoso e neuroendócrino, bem como nos parâmetros biológicos e bioquímicos. Apesar de todas estas constatações e devido a muitas controvérsias entre vários autores, faz-se necessário um estudo mais específico e aprofundado sobre o assunto.The technologic development has increased the number of electric and electronic devices for household and work environment applications. In this way, we have to cope with a diverse quantity of electromagnetic irradiation sources, with different power and frequency ranges. For many years, some scientists and engineers believed that low-frequencies electromagnetic field (EMF could not cause any bad effect or substantial alterations on the biologic livings. This work has the objective to perform a literature review of the possible effects of EMF in human beings and animals, that was published in the

  15. Effect of substrate temperature and input power on TiN film deposition by low-frequency (60 Hz) PECVD

    CERN Document Server

    Kim, H T; Han, D H; Park, D K

    2000-01-01

    Titanium nitride (TiN) thin films were prepared by low-frequency (60 Hz) plasma-enhanced chemical-vapor deposition (LF-PECVD) using a mixture of TiCl sub 4 and N sub 2 as source materials and H sub 2 as an atmospheric material. The LF sub P ECVD can be used as a new method for process control at a lower deposition temperature, and the apparatus is simpler than others. The effects of the substrate temperature and the input power on the characteristics of the TiN films deposited by using LF-PECVD were investigated. The SEM results showed that the deposition rate increased as the substrate temperature and the input power increased. The crystalline TiN films had a strong crystallographically preferred orientation of (200) on the XRD patterns. The electrical resistivity of the TiN films had a tendency to decrease with increasing substrate temperature, but did not exhibit any unique tendency with increasing input power. The TiN films had high IR reflection and an edge in the visible region. The reflectance of the f...

  16. Ntp technical report on toxicity, reproductive, and developmental studies of 60-Hz magnetic fields, administered by whole body exposure to F344/N rats, Sprague-Dawley rats, and B6C3F1 mice. Toxicity report series

    Energy Technology Data Exchange (ETDEWEB)

    Boorman, G.A.

    1996-09-01

    Electric and magnetic fields are associated with the production, transmission, and use of electricity; thus the potential for human exposure is high. These electric and magnetic fields are predominantly of low frequency (60 Hz) and generally of low intensity. The prevailing view among physicists is that exposure to these low-frequency, low-intensity fields does not pose a health hazard. However, this view has been challenged by reports linking magnetic field exposure to the development of leukemia and other cancers. Because multiple epidemiologic studies suggested a potential for increased cancer rates with increasing exposure, and because of public concern, the effects of 60-Hz magnetic field exposure were examined in F344/N rats and B6C3F1 mice in 8-week full-body-exposure studies. Animals were evaluated for hematology and clinical chemistry (rats only) parameters, pineal gland hormone concentrations, and histopathology. Additional studies were performed in Sprague-Dawley rats to examine teratologic and reproductive effects of magnetic field exposure.

  17. Effects of 60 Hz electromagnetic fields on early growth in three plant species and a replication of previous results

    Energy Technology Data Exchange (ETDEWEB)

    Davis, M.S. [Univ. of Sunderland (United Kingdom). Ecology Centre

    1996-05-01

    In an attempt to replicate the findings of Smith et al., seeds of Raphanus sativus L. (radish), Sinapsis alba L. (mustard), and Hordeum vulgare L. (barley) were grown for between 9 and 21 days in continuous electromagnetic fields (EMFs) at ion-cyclotron resonance conditions for stimulation of Ca{sup 2+} (B{sub H} = 78.3 {micro}T, B{sub HAC} = 40 {micro}T peak-peak at 60 Hz, B{sub v} = 0). On harvesting, radish showed results similar to those of Smith et al. Dry stem weight and plant height were both significantly greater (Mann-Whitney tests, Ps < 0.05) in EMF-exposed plants than in control plants in each EMF experiment. Wet root weight was significantly greater in EMF-exposed plants in two out of three experiments, as were dry leaf weight, dry whole weight, and stem diameter. Dry root weight, wet leaf weight, and wet whole weight were significantly greater in EMF-exposed plants in one of three experiments. All significant differences indicated an increase in weight or size in the EMF-exposed plants. In each of the sham experiments, no differences between exposed and control plants were evident. Mustard plants failed to respond to the EMFs in any of the plant parameters measured. In one experiment, barley similarly failed to respond; but in another showed significantly greater wet root weight and significantly smaller stem diameter and dry seed weight at the end of the experiment in exposed plants compared to control plants. Although these results give no clue about the underlying bioelectromagnetic mechanism, they demonstrate that, at least for one EMF-sensitive biosystem, results can be independently replicated in another laboratory. Such replication is crucial in establishing the validity of bioelectromagnetic science.

  18. Melatonin rhythm onset in the adult siberian hamster: influence of photoperiod but not 60-Hz magnetic field exposure on melatonin content in the pineal gland and in circulation.

    Science.gov (United States)

    Yellon, S M; Truong, H N

    1998-02-01

    To determine the relationship between pineal melatonin production and its appearance in circulation, the rising phase of the pineal and serum melatonin rhythm was studied in the adult Siberian hamster. Melatonin concentrations increased in the pineal gland and in serum at 1.50 and 1.75 h, respectively, relative to lights off in long days (16 h of light/day) and at 2.00 and 2.75 h, respectively, in short days (10 h of light/day). Thus, a photoperiod-dependent melatonin rise in circulation lagged production by the pineal gland by 0.50 h--a delay of 0.75 h in short-day hamsters versus 0.25 h in long-day hamsters. Following initiation of this rise, concentrations that were typical of the nighttime peak were achieved within 2 h of melatonin rhythm onset, regardless of photoperiod. To determine whether clock control of the rising phase of the melatonin rhythm, in the absence of photoperiod cues, may be disrupted by perturbations in the ambient magnetic field, hamsters in constant darkness were acutely exposed to a 1-Gauss, 60-Hz magnetic field for 15 min or were daily exposed to this treatment for 14 or 21 days. Neither the melatonin rise in pineal content or circulation during subjective night was affected by acute or chronic magnetic field exposures; testes regression similarly occurred in sham and daily magnetic field-exposed hamsters in constant darkness. These findings indicate that magnetic field exposures are unlikely to serve as a zeitgeber for the circadian mechanism that controls onset of the melatonin rhythm; rather, photoperiod is a predominant cue that may differentially regulate the rising phase of melatonin production in the pineal gland and concentration in circulation.

  19. Preliminary study of the behavioral and biological effects of high intensity 60 Hz electric fields. Quarterly technical progress report, No. 1. [Development and testing of experimental protocols and apparatus

    Energy Technology Data Exchange (ETDEWEB)

    1978-08-01

    The major objective of this preliminary study is to develop and thoroughly test the experimental protocols and apparatus, which are planned for a major study of the behavioral and biological effects of high intensity 60 Hz electric fields. The behavior of baboons will be observed before, during, and after exposure to 60 Hz electric fields at a maximum intensity of 60 kV/m. Both individual performance (operant conditioning) and social behavior will be examined. The preliminary study will differ from the planned major study as follows: subjects will be used as their own controls; a smaller number of subjects will be run; field intensity will not be varied; the electric field should be non-uniform; the preliminary study exposure facility will be basically an outdoor facility; to avoid deterioration of plastic materials, the high intensity fields will not be turned on during or just after rainfall; and in the preliminary study the biological work will be restricted to the clinical determination of the health of subjects before and after exposure. The present report is the first of three quarterly technical progress reports. It covers approximately the first two and one-half months of activity and, therefore, consists primarily of plans. The report addresses four major areas: the high intensity field exposure facility; the field measurement instrumentation; the operation conditioning equipment; and experimental methods including experimental design and data analysis.

  20. Modelling fields induced in humans by 50/60 Hz magnetic fields: reliability of the results and effects of model variations

    International Nuclear Information System (INIS)

    This paper presents a comparison of anatomically realistic human models and numerical codes in the dosimetry of power frequency magnetic fields. The groups at the University of Victoria and the National Radiological Protection Board have calculated the induced electric fields in both their 'UVic' and 'NORMAN' models using independently developed codes. A detailed evaluation has been performed for a uniform magnetic field at 60 Hz. Comparisons of all dosimetric metrics computed in each particular model agree within 2% or less. Since in situ measurements cannot be performed in humans, and achievable accuracy of measurements in models and animals is not likely to be better than 10-15%, the comparisons presented should provide confidence limits on computational dosimetry. An evaluation of the effect of model size, shape and resolution has also been performed and further illuminated the reasons for differences in induced electric fields for various human body models. (author)

  1. [The present state of knowledge concerning the effect of electromagnetic fields of 50/60 Hz on the circulatory system and the autonomic nervous system].

    Science.gov (United States)

    Indulski, J A; Bortkiewicz, A; Zmyślony, M

    1997-01-01

    Diseases of the circulatory system together with neoplastic diseases are recognised as the major health problem in the contemporary world. Their origin and aggravation may be related to the exposure to electromagnetic fields (EMFs) since theoretically, disorders in the functioning of the circulatory system are most likely due to electric impulses generated in it by external magnetic fields. The nervous system, including its autonomic part which regulates, among others, the functioning of the circulatory system, because of its electric nature is another system which may be disturbed by EMFs. From the 1960s, biological studies on the effects of power-line frequency EMFs have been carried out in many countries. In view of the applied study model, four main directions of these studies can be identified: in vitro and in vivo animal experiments, experimental studies on humans, clinical and epidemiological studies. Experimental studies on animals and humans have yielded ambiguous and very often contradictory results. Some of them indicate that EMF contributes to slowing down the cardiac rhythm and the stroke volume of the left ventricle, other results suggest their acceleration, and still other show no differences. The results of clinical studies performed in many countries in different groups of workers exposed to power-line frequency EMFs have not produced the evidence for drawing unequivocal conclusions. Again some studies reveal that those exposed show disorders in neurovegetative and blood pressure regulations (hypotension or hypertension) as well as in cardiac rhythm (bradycardia or tachycardia). Other studies do not confirm harmful effect of EMF on the circulatory system. Therefore, it is not feasible to find out, on the basis of these studies, whether and how chronic exposure to power-line frequency EMFs influences the functioning of the circulatory system, the more so as ECG standard recording has been to date the only diagnostic method, and according to the

  2. Cardiovascular response of rats exposed to 60-Hz electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Hilton, D.I.; Phillips, R.D.

    1980-01-01

    Recently, it has been reported that exposure to high-strength electric fields can influence electrocardiogram (ECG) patterns, heart rates, and blood pressures in various species of animals. Our studies were designed to evaluate these reported effects and to help clarify some of the disagreement present in the literature. Various cardiovascular variables were measured in Sprague-Dawley rats exposed or sham-exposed to 60-Hz electric fields at 80 to 100 kV/m for periods up to four months. No significant differences in heart rates, ECG patterns, blood pressures, or vascular reactivity were observed between exposed and sham-exposed rats after 8 hours, 40 hours, 1 month, or 4 months of exposure. Our studies cannot be directly compared to the work of other investigators because of differences in animal species and electric-field characteristics. However, our failure to detect any cardiovascular changes may have been the result of (1) eliminating secondary field effects such as shocks, audible noise, corona, and ozone; (2) minimizing steady-state microcurrents between the mouth of the animal and watering devices; and (3) minimizing electric-field-induced vibration of the electrodes and animal cages.

  3. Physiological variables and subjective symptoms by 60 Hz magnetic field in EHS and non-EHS persons.

    Science.gov (United States)

    Nam, Ki Chang; Choi, Jae Lim; Kwon, Min Kyung; Jang, Kyung Hwan; Kim, Deok Won

    2011-01-01

    Electromagnetic hypersensitivity (EHS) is a set of claims of adverse medical symptoms self attributed by exposure to electromagnetic field. In this study, we simultaneously investigated both physiological changes (heart rate, respiration rate, and heart rate variability) and subjective symptoms to determine the origin of EHS. Two volunteer groups (15 self-reported EHS and 16 non-EHS participants) were tested under both sham and real exposure to 12.5 μT magnetic fields at 60 Hz that lasted a half an hour. The magnetic field exposure did not have any effect on physiological variables or subjective symptoms in either group. We conclude that the subjective symptoms did not result from exposure to 12.5 μT magnetic field at 60 Hz. PMID:22254708

  4. Computer simulation of induced electric currents and fields in biological bodies by 60 Hz magnetic fields

    International Nuclear Information System (INIS)

    Possible health effects of human exposure to 60 Hz magnetic fields are a subject of increasing concern. An understanding of the coupling of electromagnetic fields to human body tissues is essential for assessment of their biological effects. A method is presented for the computerized simulation of induced electric currents and fields in bodies of men and rodents from power-line frequency magnetic fields. In the impedance method, the body is represented by a 3 dimensional impedance network. The computational model consists of several tens of thousands of cubic numerical cells and thus represented a realistic shape. The modelling for humans is performed with two models, a heterogeneous model based on cross-section anatomy and a homogeneous one using an average tissue conductivity. A summary of computed results of induced electric currents and fields is presented. It is confirmed that induced currents are lower than endangerous current levels for most environmental exposures. However, the induced current density varies greatly, with the maximum being at least 10 times larger than the average. This difference is likely to be greater when more detailed anatomy and morphology are considered. 15 refs., 2 figs., 1 tab

  5. 50-60 Hz frequency electric and magnetic fields; Champs electriques et magnetiques de frequence 50-60 Hz

    Energy Technology Data Exchange (ETDEWEB)

    Lambrozo, J. [Electricite de France (EDF), 75 - Paris (France). Service Etudes Medicales

    1999-07-01

    After more than twenty years of research, if biological effects exist for electromagnetic fields intensity over 1000 times the public usual exposure levels, the demonstration of a risk for health has not been brought. The actual data do not demonstrate that these fields can be dangerous for Health, more particularly, no solid nor conclusive proof shows that the residential exposure to electromagnetic fields can be responsible of cancer, undesirable neurological effects, or effects about the reproduction or development ( report extract of the Academy of Sciences in Usa, october 1996). (N.C.)

  6. Electric and magnetic fields with a frequency of 50-60 Hz: assessment of 20 years of research

    Energy Technology Data Exchange (ETDEWEB)

    Lambrozo, J. [Electricite de France - Gaz de France, Paris (France)

    2001-07-01

    Since electricity is used everywhere, exposure to electromagnetic fields of extremely low frequency (50-60 Hz) is unavoidable in our daily life. The question of whether these electromagnetic fields could possibly have any biological or health effects has been a major environmental issue for more than 20 years. At high field strengths, biological effects such as nerve and cardio-stimulation through the induction of currents in the body have been noted. These biological effects have been used in the drafting of standards for public and professional exposure. However, it is the search for effects at low field levels that has been the focus of much research. The main results of this research can be summarised as follows: in vivo studies on whole animals have shown that there is no convincing evidence that electromagnetic fields cause cancer or birth defects, and despite some reduction in pineal and blood melatonin in rodents, studies on lambs, baboons and humans do not support such an effect of electromagnetic fields, while in vitro studies have shown that exposure to electromagnetic fields at usual residential levels (<100 {mu}T) does not produce any significant in vitro effects that could be replicated in independent studies. These results, correlated with the data provided by more recent epidemiological studies, do not show that exposure to electromagnetic fields at the usual residential exposure levels presents a human health hazard. (author)

  7. Numerical calculation and measurement of 60-Hz current densities induced in an upright grounded cylinder.

    Science.gov (United States)

    Kaune, W T; McCreary, F A

    1985-01-01

    Power-frequency electric fields are strongly perturbed in the vicinity of human beings and experimental animals. As a consequence, the extrapolation of biological data from laboratory animals to human-exposure situations cannot use the unperturbed exposure field strength as a common exposure parameter. Rather, comparisons between species must be based on the actual electric fields at the outer surfaces of and inside the bodies of the subjects. Experimental data have been published on surface and internal fields for a few exposure situations, but it is not feasible to characterize experimentally more than a small fraction of the diverse types of exposures which occur in the laboratory and in the field. A predictive numerical model is needed, one whose predictions have been verified in situations where experimental data are available, and one whose results can be used with confidence in new exposure situations. This paper describes a numerical technique which can be used to develop such a model, and it carries out this development for a test case, that of a homogeneous right-circular cylinder resting upright on-end on a ground plane and exposed to a vertical, uniform, 60-Hz electric field. The accuracy of the model is tested by comparing short-circuit currents and induced current densities predicted by it to measured values: Agreement is good. PMID:3836665

  8. Deficits in High- (> 60 Hz Gamma-Band Oscillations during Visual Processing in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Christine eGruetzner

    2013-03-01

    Full Text Available Current theories of the pathophysiology of schizophrenia have focused on abnormal temporal coordination of neural activity. Oscillations in the gamma-band range (> 25 Hz are of particular interest as they establish synchronisation with great precision in local cortical networks. However, the contribution of high gamma (> 60 Hz oscillations towards the pathophysiology is less established. To address this issue, we recorded magnetoencephalographic (MEG data from 16 medicated patients with chronic schizophrenia and 16 controls during the perception of Mooney faces. Magnetoencephalographic data were analysed in the 25-150 Hz frequency range. Patients showed elevated reaction times and reduced detection rates during the perception of upright Mooney faces while responses to inverted stimuli were intact. Impaired processing of Mooney faces in schizophrenia patients was accompanied by a pronounced reduction in spectral power between 60-120 Hz (effect size: d = 1.26 which was correlated with disorganised symptoms (r = -.72. Our findings demonstrate that deficits in high gamma-band oscillations as measured by MEG are a sensitive marker for aberrant cortical functioning in schizophrenia, suggesting an important aspect of the pathophysiology of the disorder.

  9. Anecdotal report of magneto-phosphene perception in 50 mT 20, 50 and 60 Hz magnetic fields

    International Nuclear Information System (INIS)

    Magneto-phosphenes are described as flickering lights appearing in the visual field, due to retinal exposure to time-varying magnetic fields (MF). Human magneto-phosphene perception (MP) serves as a scientific basis for inter- national guidelines intending to limit exposure to electromagnetic fields in the extremely low frequency range. However, the flux density threshold at which MP occurs, as well as the dose and frequency responses of the phenomenon, are not clearly experimentally established. The 50-60 Hz threshold is extrapolated from data in the lower frequency range. The objective of this paper is to provide a descriptive anecdotal report of MP from 8 individuals exposed to 50 mT MF at 20, 50 and 60 Hz. They describe variations of flickering light perceptions in the visual field, matching the description by D'Arsonval (1896). This preliminary testing introduces a new experimental protocol, which will test the threshold for MP and other associated neuro-physiological responses in humans. (authors)

  10. Intracerebroventricular injection of mu- and delta-opiate receptor antagonists block 60 Hz magnetic field-induced decreases in cholinergic activity in the frontal cortex and hippocampus of the rat.

    Science.gov (United States)

    Lai, H; Carino, M

    1998-01-01

    In previous research, we have found that acute exposure to a 60 Hz magnetic field decreased cholinergic activity in the frontal cortex and hippocampus of the rat as measured by sodium-dependent high-affinity choline uptake activity. We concluded that the effect was mediated by endogenous opioids inside the brain because it could be blocked by pretreatment of rats before magnetic field exposure with the opiate antagonist naltrexone, but not by the peripheral antagonist naloxone methiodide. In the present study, the involvement of opiate receptor subtypes was investigated. Rats were pretreated by intracerebroventricular injection of the mu-opiate receptor antagonist, beta-funaltrexamine, or the delta-opiate receptor antagonist, naltrindole, before exposure to a 60 Hz magnetic field (2 mT, 1 hour). It was found that the effects of magnetic field on high-affinity choline uptake in the frontal cortex and hippocampus were blocked by the drug treatments. These data indicate that both mu- and delta-opiate receptors in the brain are involved in the magnetic field-induced decreases in cholinergic activity in the frontal cortex and hippocampus of the rat.

  11. Electric and magnetic fields having a 50/60 hz frequency; Champs electriques et magnetiques de frequence 50/60 Hz

    Energy Technology Data Exchange (ETDEWEB)

    Lambrozo, J.; Touitou, Y. [Electricite de France (EDF), Service des Etudes Medicales, 93 - Saint-Denis (France)]|[Hopital Pitie-Salpetriere, Service de Biochimie Medicale, Faculte de Medecine, 75 - Paris (France)

    2001-07-01

    If variations of pineal or plasmatic rate of melatonin have been underlined with the rodent, with the man it does not appear that the electromagnetic fields exposure involve a significant change at the melatonin level or its principal metabolite. (N.C.)

  12. Analytical and experimental discussion of a circuit-based model for compact fluorescent lamps in a 60 Hz power grid

    Directory of Open Access Journals (Sweden)

    G. Malagon Carvajal

    2015-11-01

    Full Text Available This article presents an analysis and discussion on the performance of a circuit-based model for Compact Fluorescent Lamps (CFL in a 120 V 60 Hz power grid. This model is proposed and validated in previous scientific literature for CFLs in 230 V 50 Hz systems. Nevertheless, the derivation of this model is not straightforward to follow and its performance in 120 V 60 Hz systems is a matter of research work. In this paper, the analytical derivation of this CFL model is presented in detail and its performance is discussed when predicting the current of a CFL designed to operate in a 120 V 60 Hz electrical system. The derived model is separately implemented in both MATLAB® and ATP-EMTP® software using two different sets of parameters previously proposed for 230 V 50 Hz CFLs. These simulation results are compared against laboratory measurements using a programmable AC voltage source. The measurements and simulations considered seven CFLs 110/127 V 60 Hz with different power ratings supplied by a sinusoidal (not distorted voltage source. The simulations under these conditions do not properly predict the current measurements and therefore the set of parameters and/or the model itself need to be adjusted for 120 V 60 Hz power grids.

  13. 试验站10 kV/60 Hz 机组电源实现及应用

    Institute of Scientific and Technical Information of China (English)

    张毅峰; 廉永峰

    2014-01-01

    为满足试验站10 kV/60 Hz 电源能力,采用了50 Hz 同步电动机拖动60 Hz 同步发电机组的方案,可实现50 Hz/60 Hz 电源无功补偿,改善整个试验电源网络的功率因数,并能实现整个试验设备软启动,大大降低了大容量变压器及单相变压器挂网瞬间对供电系统网络及试验设备的冲击。

  14. Operation planning studies for the integration of the 60 Hz Itaipu units in the Brazilian interconnected system

    Energy Technology Data Exchange (ETDEWEB)

    Chipp, H.J.; Oliveira, J.C.C. [ELETROBRAS, Rio de Janeiro, RJ (Brazil); Correa, L.R.A. [FURNAS, Rio de Janeiro, RJ (Brazil); Mendonca, W.C.; Marchi, R.D. [Itaipu Binacional, Foz do Iguacu, PR (Brazil); Botelho, M.J. [ELETROSUL, Curitiba, PR (Brazil)

    1987-12-31

    This paper describes the operation planning studies necessary to interconnect the first two 60 Hz generator units of the Itaipu power plant to the Brazilian interconnected system. The criteria, main problems identified and operative solutions encountered are presented in this paper. 10 refs., 4 figs., 5 tabs.

  15. Power line harmonic radiation observed by the DEMETER spacecraft at 50/60 Hz and low harmonics

    Science.gov (United States)

    Němec, F.; Parrot, M.; Santolík, O.

    2015-10-01

    We present a low-altitude satellite survey of Power Line Harmonic Radiation (PLHR), i.e., electromagnetic waves radiated by electric power systems on the ground. We focus on frequencies corresponding to the first few harmonics of the base power system frequencies (50 Hz or 60 Hz, depending on the region). It is shown that the intensities of electromagnetic waves detected at these frequencies at an altitude of about 700 km are significantly enhanced above industrialized areas. The frequencies at which the wave intensities are increased are in excellent agreement with base power system frequencies just below the satellite location. We also investigate a possible presence of the weekend effect, i.e., if the situation is different during the weekends when the power consumption is lower than during the weekdays. Such an effect might be possibly present in the European region, but it is very weak. PLHR effects are less often detected in the summer, as the ionospheric absorption increases, and also, the radiation is obscured by lightning generated emissions. This difference is smaller in the U.S. region, in agreement with the monthly variations of the power consumption. The analysis of the measured frequency spectra reveals that although intensity increases at low odd harmonics of base power system frequencies are routinely detected, low even harmonics are generally absent. Finally, we verify the relation of PLHR intensities to the geomagnetically induced currents (GICs) proxy. It is shown that the PLHR intensity is increased at the times of higher GIC proxy values during the night.

  16. Biological effects of high strength electric fields on small laboratory animals. Annual report, April 1977--March 1978

    Energy Technology Data Exchange (ETDEWEB)

    1978-04-01

    Progress is reported on studies of the biological effects on mice and rats of exposure to 60-Hz electric fields. Results are reported on the effects of 30-day and 60-day exposures to 100 kV/m, 60-Hz electric fields on hematologic values, blood chemistry, and organ weights. With the possible exception of elevated blood platelet counts following 60-day exposures, there were no pathological changes observed in either mice or rats.

  17. BIGEL analysis of gene expression in HL60 cells exposed to X rays or 60 Hz magnetic fields

    Science.gov (United States)

    Balcer-Kubiczek, E. K.; Zhang, X. F.; Han, L. H.; Harrison, G. H.; Davis, C. C.; Zhou, X. J.; Ioffe, V.; McCready, W. A.; Abraham, J. M.; Meltzer, S. J.

    1998-01-01

    We screened a panel of 1,920 randomly selected cDNAs to discover genes that are differentially expressed in HL60 cells exposed to 60 Hz magnetic fields (2 mT) or X rays (5 Gy) compared to unexposed cells. Identification of these clones was accomplished using our two-gel cDNA library screening method (BIGEL). Eighteen cDNAs differentially expressed in X-irradiated compared to control HL60 cells were recovered from a panel of 1,920 clones. Differential expression in experimental compared to control cells was confirmed independently by Northern blotting of paired total RNA samples hybridized to each of the 18 clone-specific cDNA probes. DNA sequencing revealed that 15 of the 18 cDNA clones produced matches with the database for genes related to cell growth, protein synthesis, energy metabolism, oxidative stress or apoptosis (including MYC, neuroleukin, copper zinc-dependent superoxide dismutase, TC4 RAS-like protein, peptide elongation factor 1alpha, BNIP3, GATA3, NF45, cytochrome c oxidase II and triosephosphate isomerase mRNAs). In contrast, BIGEL analysis of the same 1,920 cDNAs revealed no differences greater than 1.5-fold in expression levels in magnetic-field compared to sham-exposed cells. Magnetic-field-exposed and control samples were analyzed further for the presence of mRNA encoding X-ray-responsive genes by hybridization of the 18 specific cDNA probes to RNA from exposed and control HL60 cells. Our results suggest that differential gene expression is induced in approximately 1% of a random pool of cDNAs by ionizing radiation but not by 60 Hz magnetic fields under the present experimental conditions.

  18. Effects of electromagnetic field exposure on the heart: a systematic review.

    Science.gov (United States)

    Elmas, Onur

    2016-01-01

    The use of electrical devices has gradually increased throughout the last century, and scientists have suggested that electromagnetic fields (EMF) generated by such devices may have harmful effects on living creatures. This work represents a systematic review of collective scholarly literature examining the effects of EMFs on the heart. Although most works describing effects of EMF exposure have been carried out using city electric frequencies (50-60 Hz), a consensus has not been reached about whether long- or short-term exposure to 50-60 Hz EMF negatively affects the heart. Studies have indicated that EMFs produced at cell-phone frequencies cause no-effect on the heart. Differences between results of studies may be due to a compensatory response developed by the body over time. At greater EMF strengths or shorter exposures, the ability of the body to develop compensation mechanisms is reduced and the potential for heart-related effects increases. It is noteworthy that diseases of heart tissues such as myocardial ischemia can also be successfully treated using EMF. Despite the substantial volume of data that has been collected on heart-related effects of EMFs, additional studies are needed at the cellular and molecular level to fully clarify the subject. Until the effects of EMF on heart tissue are more fully explored, electronic devices generating EMFs should be approached with caution. PMID:24021427

  19. Effects of electromagnetic field exposure on the heart: a systematic review.

    Science.gov (United States)

    Elmas, Onur

    2016-01-01

    The use of electrical devices has gradually increased throughout the last century, and scientists have suggested that electromagnetic fields (EMF) generated by such devices may have harmful effects on living creatures. This work represents a systematic review of collective scholarly literature examining the effects of EMFs on the heart. Although most works describing effects of EMF exposure have been carried out using city electric frequencies (50-60 Hz), a consensus has not been reached about whether long- or short-term exposure to 50-60 Hz EMF negatively affects the heart. Studies have indicated that EMFs produced at cell-phone frequencies cause no-effect on the heart. Differences between results of studies may be due to a compensatory response developed by the body over time. At greater EMF strengths or shorter exposures, the ability of the body to develop compensation mechanisms is reduced and the potential for heart-related effects increases. It is noteworthy that diseases of heart tissues such as myocardial ischemia can also be successfully treated using EMF. Despite the substantial volume of data that has been collected on heart-related effects of EMFs, additional studies are needed at the cellular and molecular level to fully clarify the subject. Until the effects of EMF on heart tissue are more fully explored, electronic devices generating EMFs should be approached with caution.

  20. Possíveis efeitos adversos dos campos eletromagnéticos (50/60 Hz) em humanos e em animais Potential adverse effects of electromagnetic fields (50/60 Hz) on humans and animals

    OpenAIRE

    Caroline Wanderley Souto Ferreira Anselmo; Francisca Martins Bion; Maria Teresa Jansem de Almeida Catanho; Maria do Carmo Medeiros

    2005-01-01

    Os avanços tecnológicos têm aumentado o número de equipamentos elétricos e eletrônicos, seja nas residências ou mesmo no ambiente de trabalho, fazendo com que a população conviva com grande número de fontes de irradiação eletromagnética, com os mais diversos níveis de potência e freqüência. Por muitos anos, alguns cientistas e engenheiros acreditaram que o campo eletromagnético (CEM) com freqüência extremamente baixa não pudesse causar efeitos e alterações significantes no material biológico....

  1. High power density, 60 Hz, single flow steam turbine with 42 inch titanium last row blade for advanced combined cycle applications

    Energy Technology Data Exchange (ETDEWEB)

    Zabrecky, J.S.; Bezugly, J.A.; Brown, M.K.; Martin, H.F.

    1999-07-01

    Highly efficient, yet economical steam turbines with large exhaust areas and increased inlet pressure and temperature capability are required to complement the growth in combustion turbine power ratings and address the pursuit of higher combined cycle plant efficiencies. This paper discussed the design of a 130--190MW, 60 Hz steam turbine which addresses these requirements for 2 x 1F, 1 x 1G and Advanced Turbine Study (ATS) combined cycle plants. Features of interest include a compact, two casing, axial exhaust, single flow design with a two piece, welded IP-LP rotor and 42 inch titanium last row blade.

  2. Final report on key comparison EURAMET.EM-K5.1 (EURAMET Project No. 687): Comparison of 50/60 Hz power

    Science.gov (United States)

    Çayci, Hüseyin

    2011-01-01

    To support the Calibration and Measurement Capabilities (CMCs) declared by members of EURAMET (formerly EUROMET) in the framework of the CIPM-MRA, a EURAMET key comparison was organized. Electrical standards of low-frequency (50/60 Hz) power were compared at ten national metrology institutes (NMIs) of EURAMET member states and at two NMIs of COOMET and APMP member states, to establish the relationship between the electrical units of AC power at these laboratories. The results of this comparison are described. The differences between the values of almost all laboratories and the EURAMET reference values were within the expanded measurement uncertainties at a coverage factor k = 2. The link between the comparisons of 50/60 Hz power conducted by the Consultative Committee for Electricity and Magnetism (CCEM) from 1996 to 2000 (CCEM-K5) and by EURAMET from 2003 to 2008 (EUROMET.EM-K5.1, Project no 687) is carried out following the example given by F Delahaye and T J Witt, in a similar way as in the previous comparison EUROMET.EM-K5, Project no 385. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  3. 60 Hz electric field changes the membrane potential during burst phase in pancreatic β-cells: in silico analysis.

    Science.gov (United States)

    Neves, Gesilda F; Silva, José R F; Moraes, Renato B; Fernandes, Thiago S; Tenorio, Bruno M; Nogueira, Romildo A

    2014-06-01

    The production, distribution and use of electricity can generate low frequency electric and magnetic fields (50-60 Hz). Considering that some studies showed adverse effects on pancreatic β-cells exposed to these fields; the present study aimed to analyze the effects of 60 Hz electric fields on membrane potential during the silent and burst phases in pancreatic β-cells using a mathematical model. Sinusoidal 60 Hz electric fields with amplitude ranging from 0.5 to 4 mV were applied on pancreatic β-cells model. The sinusoidal electric field changed burst duration, inter-burst intervals (silent phase) and spike sizes. The parameters above presented dose-dependent response with the voltage amplitude applied. In conclusion, theoretical analyses showed that a 60 Hz electric field with low amplitudes changes the membrane potential in pancreatic β-cells.

  4. 关于50Hz与60Hz高压气体绝缘开关设备互用的探讨%Discussion about Interoperability of High Voltage Gas Insulated Switchgears with Rated Frequency 50 Hz and 60 Hz

    Institute of Scientific and Technical Information of China (English)

    张猛; 穆双录; 南振乐

    2012-01-01

    To understand whether Chinese high voltage switchgears with rated frequency of 50 Hz can be exported to and directly used in the regions where the rated frequency of electric equipment is 60 Hz, and whether there are economical and available means to solve this problem, the authors collect the testing requirements of high voltage switchgears with rated frequencies of 50 Hz and 60 Hz in relevant IEC standards, and the requirements are analyzed. Furthermore, on the basis of the analysis, an economical and effective solution to the interoperability of the high voltage switchgears with both rated frequencies is proposed by way of example.%近年来中国高压开关设备的出口贸易增长迅速,额定频率为50 Hz的高压开关设备直接出口至额定频率60 Hz的地区是否适用,反之如何,是否有经济可行的方法来解决这些问题,目前并没有明确的定论.笔者汇总了相关IEC标准对额定频率50 Hz与60 Hz高压开关设备的试验要求,并对相关标准的要求进行了分析.最后基于对相关标准的理解,通过示例,提出了一种额定频率为50 Hz与60 Hz高压开关设备互用的经济可行的解决方法.

  5. Biological effects of high strength electric fields on small laboratory animals. Interim progress report, March 9, 1976--September 8, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, R.D.; Kaune, W.T.; Decker, J.R.; Hjeresen, D.L.

    1976-09-01

    Progress is reported on a broad and comprehensive series of biological experiments made under strictly controlled laboratory conditions to screen for possible effects of exposure to 60-Hz electric fields on small laboratory animals. Electric field strengths comparable to and exceeding those under existing and anticipated transmission line designs will be used. Dosimetry studies will complement the animal studies to establish the relationship between tissue dose and any observed biological effects. Information derived from this project will provide a better basis for evaluating potential hazards of exposure to 60-Hz electric fields and help define parameters to be studied in clinical evaluations on humans.

  6. Comparative Analysis Between the Middle and Small-size Turbine-generator of 50 Hz and That of 60 Hz%60 Hz与50 Hz中小型汽轮发电机之比较

    Institute of Scientific and Technical Information of China (English)

    蔡恒川; 翁祥玲; 王庆波

    2013-01-01

    阐述了中小型60 H z空冷汽轮发电机的方案设计,针对30 M W以下的中小型机组,从设计角度与国内50 H z同等容量的产品进行比较,探讨两种频率发电机主要电气性能参数及结构特点的异同。%Program design of the middle and small-size turbine-generator of 60 Hz was described. For power less than 30 MW, comparative analysis between the middle and small-size turbine-generator of 50 Hz and that of 60 Hz was done under same power capacity. Main electric performance data as well as their difference in the ifeld of construction of these two type generator with different frequency were discussed.

  7. Heat exposure effects among firefighters

    Directory of Open Access Journals (Sweden)

    Patel Harshad

    2006-01-01

    Full Text Available Background: Firefighting is a hazardous occupation. The firefighters (FF in extinguishing fire are often exposed to extreme heat of 1200oC to 1400oC temperature. The heat exposure effects may occur from hot air, radiant heat, contact with hot surfaces, endogenous heat produced by the body during exercise, which cannot be cooled during fire. A significant morbidity and mortality from exposure to heat was reported in other countries but not from India. Aims : Present study focuses on prevalence of heat exposure effects i.e., heat exhaustion, heat syncope, heat pyrexia and heat cramps recorded among fire fighters of Ahmedabad fire brigade. Settings: Ahmedabad fire brigade (AFB of Ahmedabad municipal corporation. Design: Cross sectional. Materials and Methods: Present study focuses on prevalence of heat exposure effects i.e., heat exhaustion, heat syncope, heat pyrexia and heat cramps recorded between 262 FF of AFB. This prevalence′s were observed among firemen those directly exposed to heat in combating fire and others (load trucks, pump trucks etc. that assist the firemen. These were seen in different age groups (< 30; 31-45 and> 45 yrs, duration of exposure (< 10; 11-20 and> 21 yrs.The number of accidents associated with heat exposure was analyzed. Statistical Analysis: Prevalence comparison by Chi-square test. Results: The results revealed that a total of 53 (20.0% FF reported health exposure effects and were higher among firemen than other groups. Heat exhaustion 48 (18.3%; heat syncope 11(4.2%; heat pyrexia 11 (4.2% and heat cramps 16(6.1% were reported indicating significant occurrence of heat stress among firefighters. In majority of FF, the frequency of occurrence was observed at only one instance. There were no differences according to age or duration of exposure. Among 53 FF with heat exposure effects, accident were reported in 10 (18.9% suggesting that heat stress may be responsible for this. Conclusion: Overall, Significant occurrence

  8. Effects of Exposure Imprecision on Estimation of the Benchmark Dose

    DEFF Research Database (Denmark)

    Budtz-Jørgensen, Esben; Keiding, Niels; Grandjean, Philippe

    Environmental epidemiology; exposure measurement error; effect of prenatal mercury exposure; exposure standards; benchmark dose......Environmental epidemiology; exposure measurement error; effect of prenatal mercury exposure; exposure standards; benchmark dose...

  9. Medical exposure and the effects of radiation

    International Nuclear Information System (INIS)

    Radiation gives cracks to genes. The influence is divided into deterministic effect with a threshold value, and the stochastic effect (tumor and genetic effect) which increases according to the exposure amount. Although we are put to various non-artificial radiations, which we cannot be avoided, on the earth, the contamination by artificial radiation can be defended. Artificial radioactive exposure includes medical exposure and non-medical exposure for example by nuclear power plant. As to medical examinations using radiation, the inquiry about the radiation exposure is increasing after the occurrence of the first nuclear power plant disaster of Fukushima. While concern about non-medical radioactive exposure increases, the uneasiness to medical irradiation is also increasing. The dose limit by artificial radioactive exposure other than medical exposure is set up in order to prevent the influence on the health. While the dose limit of the public exposure is set to the lower value than the total dose of non-artificial exposure concerning of a safety margin for all people, the dose limit of medical exposure is not defined, since it is thought that medical irradiation has a benefit for those who receive irradiation. Making an effort to decrease the radiation dose in performing the best medical treatment is the responsibility with which we are burdened. (author)

  10. Design of First Sub- critical 350 MW -60 Hz Turbine in China%国产首台亚临界350MW-60Hz汽轮机的研制

    Institute of Scientific and Technical Information of China (English)

    张启林; 崔贤基

    2011-01-01

    The first homebred 350MW - 60Hz turbine was developed independently by Harbin Turbine Factory ( HTC ). It was sub - critical, with two casings and two exhaust turbines, installed in Brazil Can-diota power plant. This paper presents the design characteristics of the turbine, especially discusses the special design aiming at the high speed characteristics. This chapter can provide some references for other designers, and help to know more about the design of this special turbine.%哈汽自主开发的国产首台350 MW-60 Hz汽轮机为亚临界、双缸和双排汽机组,被安装在巴西坎迪奥塔火电厂.本文介绍了机组的设计特点,并且针对高转速的特点采用的特殊设计进行了论述.本文可供同行参考,有助于加深对该种特殊机型设计上的了解.

  11. Neurobehavioral and neurodevelopmental effects of pesticide exposures

    DEFF Research Database (Denmark)

    London, Leslie; Beseler, Cheryl; Bouchard, Maryse F;

    2012-01-01

    The association between pesticide exposure and neurobehavioral and neurodevelopmental effects is an area of increasing concern. This symposium brought together participants to explore the neurotoxic effects of pesticides across the lifespan. Endpoints examined included neurobehavioral, affective ...

  12. Neurobehavioral effects of developmental methylmercury exposure

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, S.G.; Grant-Webster, K.S. [Univ. of Washington, Seattle, WA (United States)

    1995-09-01

    Methylmercury (MeHg) is a global environmental problem and is listed by the International Program of Chemical Safety as one of the six most dangerous chemicals in the world`s environment. Human exposure to MeHg primarily occurs through the consumption of contaminated food such as fish, although catastrophic exposures due to industrial pollution have occurred. The fetus is particularly sensitive to MeHg exposure and adverse effects on infant development have been associated with levels of exposure that result in few, if any, signs of maternal clinical illness or toxicity. High levels of prenatal exposure in humans result in neurobehavioral effects such as cerebral palsy and severe mental retardation. Prenatal exposure to MeHg in communities with chronic low-level exposure is related to decreased birthweight and early sensorimotor dysfunction such as delayed onset of walking. Neurobehavioral alterations have also been documented in studies with non human primates and rodents. Available information on the developmental neurotoxic effects of MeHg, particularly the neurobehavioral effects, indicates that the fetus and infant are more sensitive to adverse effects of MEHg. It is therefore recommended that pregnant women and women of childbearing age be strongly advised to limit their exposure to potential sources of MeHg. Based on results from human and animal studies on the developmental neurotoxic effects of methylmercury, the accepted reference dose should be lowered to 0.025 to 0.06 MeHg {mu}g/kg/day. Continued research on the neurotoxic effects associated with low level developmental exposure is needed. 107 refs., 3 tabs.

  13. Skin Exposures & Effects in the Workplace

    Science.gov (United States)

    ... message, please visit this page: About CDC.gov . Workplace Safety & Health Topics Skin Exposures and Effects Recommendations ... Pinterest Twitter YouTube NIOSH Homepage NIOSH A-Z Workplace Safety & Health Topics Publications and Products Programs Contact ...

  14. Effects of whole body exposure to extremely low frequency electromagnetic fields (ELF-EMF on serum and liver lipid levels, in the rat

    Directory of Open Access Journals (Sweden)

    Elias-Viñas David

    2007-11-01

    Full Text Available Abstract Backgound The effects of extremely low-frequency electromagnetic fields (ELF-EMF on the blood serum and liver lipid concentrations of male Wistar rats were assessed. Methods Animals were exposed to a single stimulation (2 h of ELF-EMF (60 Hz, 2.4 mT or sham-stimulated and thereafter sacrificed at different times (24, 48 or 96 h after beginning the exposure. Results Blood lipids showed, at 48 h stimulated animals, a significant increase of cholesterol associated to high density lipoproteins (HDL-C than those observed at any other studied time. Free fatty acid serum presented at 24 h significant increases in comparison with control group. The other serum lipids, triacylglycerols and total cholesterol did not show differences between groups, at any time evaluated. No statistical differences were shown on total lipids of the liver but total cholesterol was elevated at 24 h with a significant decrease at 96 h (p = 0.026. The ELF-EMF stimulation increased the liver content of lipoperoxides at 24 h. Conclusion Single exposures to ELF-EMF increases the serum values of HDL-C, the liver content of lipoperoxides and decreases total cholesterol of the liver. The mechanisms for the effects of ELF-EMF on lipid metabolism are not well understand yet, but could be associated to the nitric oxide synthase EMF-stimulation.

  15. Medical exposure and effective dose

    International Nuclear Information System (INIS)

    The frequency of radiological diagnosis in Japan and individual population effective dose are reported. Questionnaire on radiological practice was delivered to selected medical facilities. The total number of X-ray diagnosis performed in 1991 was 180,000,000, being age-dependent in both men and women. The chest was the most common site to be examined. The number of X-ray films per examination was the highest for the stomach. The spread of ultrasound has decreased radiological practice in the obstetric field (approximately one sixth between 1979 and 1986). There was an 8-fold increase in the number of X-ray CT as of 1989 during the past decade. The total number of CT scanning in 1989 reached nearly 14,850,000 (about 16 times as much as that of 1979). The number of stomach X-ray screening increased to 7,800,000 which is twice as much as that in 1975. In the dental field, panoramic method brought about a 7-fold increase between 1974 and 1985. The frequency of nuclear medicine diagnosis has slightly increased, reaching 1,400,000 cases in 1992, and 99mTc was the most common nuclide. The total population effective dose of radiography and fluoroscopy was 179,000 mSv. The highest effective dose was associated with gastric X-ray. The effective dose equivalent per diagnosis was estimated to be 1.02 mSv (the total population/total number of radiological diagnosis). The population effective dose per person was 2.3 mSv (population effective dose equivalent/national population), which was equal to the world average of yearly effective dose equivalent of natural radiation. (S.Y.)

  16. The Epigenetic Effects of Prenatal Cadmium Exposure.

    Science.gov (United States)

    Vilahur, Nadia; Vahter, Marie; Broberg, Karin

    2015-06-01

    Prenatal exposure to the highly toxic and common pollutant cadmium has been associated with adverse effects on child health and development. However, the underlying biological mechanisms of cadmium toxicity remain partially unsolved. Epigenetic disruption due to early cadmium exposure has gained attention as a plausible mode of action, since epigenetic signatures respond to environmental stimuli and the fetus undergoes drastic epigenomic rearrangements during embryogenesis. In the current review, we provide a critical examination of the literature addressing prenatal cadmium exposure and epigenetic effects in human, animal, and in vitro studies. We conducted a PubMed search and obtained eight recent studies addressing this topic, focusing almost exclusively on DNA methylation. These studies provide evidence that cadmium alters epigenetic signatures in the DNA of the placenta and of the newborns, and some studies indicated marked sexual differences for cadmium-related DNA methylation changes. Associations between early cadmium exposure and DNA methylation might reflect interference with de novo DNA methyltransferases. More studies, especially those including environmentally relevant doses, are needed to confirm the toxicoepigenomic effects of prenatal cadmium exposure and how that relates to the observed health effects of cadmium in childhood and later life.

  17. Biological Effects of Low-Dose Exposure

    CERN Document Server

    Komochkov, M M

    2000-01-01

    On the basis of the two-protection reaction model an analysis of stochastic radiobiological effects of low-dose exposure of different biological objects has been carried out. The stochastic effects are the results published in the last decade: epidemiological studies of human cancer mortality, the yield of thymocyte apoptosis of mice and different types of chromosomal aberrations. The results of the analysis show that as dependent upon the nature of biological object, spontanous effect, exposure conditions and radiation type one or another form dose - effect relationship is realized: downwards concave, near to linear and upwards concave with the effect of hormesis included. This result testifies to the incomplete conformity of studied effects of 1990 ICRP recomendations based on the linear no-threshold hypothesis about dose - effect relationship. Because of this the methodology of radiation risk estimation recomended by ICRP needs more precisian and such quantity as collective dose ought to be classified into...

  18. Health effects of biomass exposure

    International Nuclear Information System (INIS)

    Biomass fuels such as coal, wood, crop residues, kerosene oil and dung-cakes meet the energy needs in the household sector in India and other developing countries. Crop residues and dung-cakes are largely used in rural areas, whereas wood forms the major source of fuel in urban as well as rural areas. Combustion of these fuels produces various kinds of poisonous gases such as CO, smoke, nitrogen dioxide, polycyclic aromatic hydrocarbons and respirable particulates. These gases are released in the domestic environment and they pollute the indoor air. The women and children are the one who suffer most from this air pollution. This results into a variety of health problems principally pertaining to respiratory system among the women and children. Studies on this aspect are reviewed. They point towards the positive relationship between biomass smoke and various health effects, particularly respiratory diseases. Need for research on the ways to prevent pollution due to biomass and resultant health hazards is emphasised. (M.G.B.). 25 refs., 2 tabs

  19. Biological effects and hazards of radiation exposure

    International Nuclear Information System (INIS)

    Radiation induced carcinogenesis and mutagenesis form the main risk to health from exposure to low levels of radiation. This risk effects can be at least qualitatively understood by considering the effects of radiation on cell DNA. Whilst exposure to high levels of radiation results in a number of identifiable effects, exposure to low levels of radiation may result in effects which only manifest themselves after many years. Risk estimates for low levels of radiation have been derived on the basis of a number of assumptions. In the case of uranium mine workers a major hazard arises from the inhalation of radon daughters. Whilst the correlation between radon daughter exposure and lung cancer incidence is well established, the numerical value of the risk factor is the subject of controversy. ICRP 50 gives a value of 10 cases per 106 person-years at risk per WLM (range 5-15 x 10-6 PYR-1 WLM-1). The effect of smoking on lung cancer incidence rates amongst miners is also controversial. Nevertheless, smoking by miners should be discouraged

  20. Radiation effects after exposure during prenetal development

    International Nuclear Information System (INIS)

    The embryo and fetus are very radiosensitive during the total prenatal development period. The quality and extent of radiation effects depend strongly on the developmental stage at which the exposure occurs. During the preimplantation period radiation exposure can cause death of the embryo after radiation doses of 0.2 Gy and higher. Malformations are only observed in very rare cases when genetic predispositions exist. Macroscopic-anatomical malformations are induced only after irradiation during the major organogenesis. On the basis of experimental data with mammals it is assumed that a radiation dose of about 0.2 Gy doubles the malformation risk. Studies in humans give rise to the assumption that the human embryo is more radioresistant than the embryos of mice and rats. Radiation exposure during the major organogenesis and the early fetal period lead to disturbances in the growth and developmental processes. During early fetogenesis (week 8-15 post coruption) high radiosensitity exists for the development of the central nervous system. Radiation doses of 1 Gy cause severe mental retardation in about 50% of exposed fetuses. Analysis of the dose-effect curves shows that there is probably a dose-effect curve with a threshold for this effect. It must be taken into account that radiation exposure during the fetal period also induces cancer. The studies, however, do not allow quantitative estimate of this radiation risk at present. It is therefore generally assumed that the risk is about the same level as for children. (orig.)

  1. Experimental effects of exposure to pornography

    DEFF Research Database (Denmark)

    Hald, Gert Martin; Malamuth, Neil N

    2015-01-01

    supporting violence against women (ASV). We found that lower levels of agreeableness and higher levels of past pornography consumption significantly predicted ASV. In addition, experimental exposure to pornography increased ASV but only among men low in agreeableness. This relationship was found......Using a randomly selected community sample of 200 Danish young adult men and women in a randomized experimental design, the study investigated the effects of a personality trait (agreeableness), past pornography consumption, and experimental exposure to non-violent pornography on attitudes...

  2. HELLE: Health Effects of Low Level Exposures

    International Nuclear Information System (INIS)

    The Health Council is closely involved in establishing the scientific foundation of exposure limits for substances and radiation in order to protect public health. Through the years, the Council has contributed to the formulation of principles and procedures, both for carcinogenic and for noncarcinogenic agents. As a rule, the discussion with regard to the derivation of health-based recommended exposure limits centers around the appropriateness of extrapolation methods (What can be inferred from data on high exposure levels and on experimental animals?). Generally speaking, there is a lack of direct information on the health effects of low levels of exposure. Effects at these levels cannot usually be detected by means of traditional animal experiments or epidemiological research. The capacity of these analytical instruments to distinguish between ''signal'' and ''noise'' is inadequate in most cases. Annex B of this report contains a brief outline of the difficulties and the established methods for tackling this problem. In spite of this, the hope exists that the posited weak signals, if they are indeed present, can be detected by other means. The search will have to take place on a deeper level. In other words, effort must be made to discover what occurs at underlying levels of biological organization when organisms are exposed to low doses of radiation or substances. Molecular and cell biology provide various methods and techniques which give an insight into the processes within the cell. This results in an increase in the knowledge about the molecular and cellular effects of exposure to agents, or stated differently, the working mechanisms which form the basis of the health effects. Last year, the Health Council considered that the time was ripe to take stock of the state of knowledge in this field. To this end, an international working conference was held from 19 to 21 October 1997, entitled ''Health Effects of Low Level Exposures: Scientific Developments and

  3. Microwave radiation: biological effects and exposure standards

    Energy Technology Data Exchange (ETDEWEB)

    Lindsay, I.R.

    1981-01-01

    The thermal effects of microwave radiation are well recognized and are discussed with particular reference to cataractogenesis; the possibility of an association cannot be questioned. Postulated nonthermal effects comprise an asthenic syndrome, and for the most part the disturbances lie within clinical norms and tolerances, and are reversible. World opinion on safe exposure levels for microwave radiation is varied, and this had led to national standards disparate by three to four orders of magnitude. The US and UK exposure standard of 10 mW/cm/sup 2/ was determined over two decades ago; the possibility of a change to a more restrictive level, in line with other countries, in the near future is examined. It is concluded that such a change, without scientific rationale, is not justified. Some biological implications of the microwave radiation from the solar power satellite are considered in terms of precautions to be taken by personnel working in the vicinity of the rectenna, effects on cardiac pacemakers, and any potential effects on birds. 14 references.

  4. Health effects of industrial exposure to thorium

    International Nuclear Information System (INIS)

    The objective of this project is to determine the health effects of industrial exposure to thorium and the long-term pattern of deposition of inhaled thorium and its daughter products in human tissues. We obtained the study populations from employment records of the Lindsay Chemical Company and its corporate successors. The company was primarily engaged in the extraction of thorium and rare earth chemicals from monazite ores and in the production of thorium-impregnated mantles for gas lamps. From all available records, which date back to 1925, we have identified 3542 male and 1040 female employees. 1 ref

  5. Biomolecular Effects of Cold Plasma Exposure

    Science.gov (United States)

    Mogul, Rakesh; Bolshakov, Alexander A.; Chan, Suzanne L.; Stevens, Ramsey D.; Khare, Bishun N.; Meyyappan, M.; Trent, Jonathan D.; DeVincenzi, D. (Technical Monitor)

    2002-01-01

    The effects of cold plasma exposure on Deinococcus radiodurans, plasmid DNA and model proteins were assessed using microbiological, spectrometric and biochemical techniques. Exposure of D. radiodurans, an extremely radiation resistant microbe, to O2 plasma (less than or equal to 25 W, approx. 45 mTorr, 90 min) yielded a approx. 99.999 % sterilization and the sterilization rate was increased approx. 10-fold at 100 W and 500 mTorr. AFM images shows that the exposed cells are significantly deformed and possess 50-70 nm concavities. IR analysis indicates the chemical degradation of lipids, proteins and carotenoids of the cell wall and membrane. Intracellular damage was indicated by major absorbance loss at 1245, 1651 and 1538/cm corresponding to degradation of DNA and proteins, respectively. Biochemical experiments demonstrate that plasmas induce strand scissions and crosslinking of plasmid DNA, and reduction of enzyme activity; the degradation is power dependent with total sample loss occurring in 60 s at 200 W and 500 mTorr. Emission spectroscopy shows that D. radiodurans is volatilized into CO2, CO, N2 and H2O confirming the removal of biological matter from contaminated surfaces. The O2 plasma impacts several cellular components predominantly through chemical degradation by atomic oxygen. A CO2, plasma, however, was not effective at degrading D. radiodurans, revealing the importance of plasma composition, which has implications for planetary protection and the contamination of Mars.

  6. Exposure of unionid mussels to electric current: Assessing risks associated with electrofishing

    Science.gov (United States)

    Holliman, F.M.; Kwak, T.J.; Cope, W.G.; Levine, J.F.

    2007-01-01

    Electric current is routinely applied in freshwater for scientific sampling of fish populations (i.e., electrofishing). Freshwater mussels (families Margaritiferidae and Unionidae) are distributed worldwide, but their recent declines in diversity and abundance constitute an imperilment of global significance. Freshwater mussels are not targeted for capture by electrofishing, and any exposure to electric current is unintentional. The effects of electric shock are not fully understood for mussels but could disrupt vital physiological processes and represent an additional threat to their survival. In a controlled laboratory environment, we examined the consequences of exposure to two typical electrofishing currents, 60-Hz pulsed DC and 60-Hz AC, for the survival of adult and early life stages of three unionid species; we included fish as a quality control measure. The outcomes suggest that electrical exposure associated with typical electrofishing poses little direct risk to freshwater mussels. That is, adult mussel survival and righting behaviors (indicators of sublethal stress) were not adversely affected by electrical exposure. Glochidia (larvae that attach to and become parasites on fish gills or fins) showed minimal immediate reduction in viability after exposure. Metamorphosis from glochidia to free-living juvenile mussels was not impaired after electric current simulated capture-prone behaviors (stunning) in infested host fish. In addition, the short-term survival of juvenile mussels was not adversely influenced by exposure to electric current. Any minimal risk to imperiled mussels must be weighed at the population level against the benefits gained by using the gear for scientific sampling of fish in the same waters. However, scientists sampling fish by electrofishing should be aware of mussel reproductive periods and processes in order to minimize the harmful effects to host fish, especially in areas where mussel conservation is a concern. ?? Copyright by the

  7. Affect labeling enhances exposure effectiveness for public speaking anxiety.

    Science.gov (United States)

    Niles, Andrea N; Craske, Michelle G; Lieberman, Matthew D; Hur, Christopher

    2015-05-01

    Exposure is an effective treatment for anxiety but many patients do not respond fully. Affect labeling (labeling emotional experience) attenuates emotional responding. The current project examined whether affect labeling enhances exposure effectiveness in participants with public speaking anxiety. Participants were randomized to exposure with or without affect labeling. Physiological arousal and self-reported fear were assessed before and after exposure and compared between groups. Consistent with hypotheses, participants assigned to Affect Labeling, especially those who used more labels during exposure, showed greater reduction in physiological activation than Control participants. No effect was found for self-report measures. Also, greater emotion regulation deficits at baseline predicted more benefit in physiological arousal from exposure combined with affect labeling than exposure alone. The current research provides evidence that behavioral strategies that target prefrontal-amygdala circuitry can improve treatment effectiveness for anxiety and these effects are particularly pronounced for patients with the greatest deficits in emotion regulation. PMID:25795524

  8. Effectiveness of noise in blocking electromagnetic effects on enzyme activity in the chick embryo.

    Science.gov (United States)

    Martin, A H; Moses, G C

    1995-05-01

    We have previously demonstrated that exposure of the chick embryo to a 60 Hz, 4 microT split sine wave for the first 72 hours of development causes a significant reduction in the activity of the ectoenzyme 5'-nucleotidase. This reduced activity persisted, throughout the embryonic period, despite further incubation in a field free environment. We also showed that the reduction in 5'NT activity can be localized in the developing brain to the Cerebellum. The present study reveals that superimposition of an electromagnetic noise, of similar amplitude and frequency, can mitigate the effect of the field on 5'NT activity.

  9. Minors' exposure to online pornography: prevalence, motivations, contents and effects

    OpenAIRE

    Eva González-Ortega; Begoña Orgaz-Baz

    2013-01-01

    Since Internet has made pornographic materials more available, there is a need for more research on the characteristics and implications of children's and adolescents' exposure to such materials. This study examined the prevalence and extent of minors' exposure to online pornography, the reasons for exposure, the types of images seen and the strong effects of exposure, as reported by college students. We used an online survey to collect retrospective reports of a sample of 494 students of the...

  10. Effects of Drilling Fluid Exposure to Oil and Gas Workers Presented with Major Areas of Exposure and Exposure Indicators

    Directory of Open Access Journals (Sweden)

    Eric Broni-Bediako

    2010-12-01

    Full Text Available Drilling fluid is any fluid which is circulated through a well in order to remove cuttings from a wellbore. They are used broadly in the oil and gas industry, on exploration rigs, and are critical to ensuring a safe and productive oil or gas well. During drilling, a large volume of fluids are circulated through the well and into open, partially enclosed or completely enclosed systems at elevated temperatures. When these drilling fluids are agitated during circulating process there is significant potential for chemical exposure to workers and subsequent health effects. This study seeks to identify major areas of drilling fluid exposure and health hazard associated with the use of drilling fluid. The study also presents some challenges in setting drilling fluid exposure standard which has always not been given the same attention or concern as effects and risk management of drilling fluid. Some exposure indicators are also presented.

  11. Inferior retinal light exposure is more effective than superior retinal exposure in suppressing melatonin in humans

    Science.gov (United States)

    Glickman, Gena; Hanifin, John P.; Rollag, Mark D.; Wang, Jenny; Cooper, Howard; Brainard, George C.

    2003-01-01

    Illumination of different areas of the human retina elicits differences in acute light-induced suppression of melatonin. The aim of this study was to compare changes in plasma melatonin levels when light exposures of equal illuminance and equal photon dose were administered to superior, inferior, and full retinal fields. Nine healthy subjects participated in the study. Plexiglass eye shields were modified to permit selective exposure of the superior and inferior halves of the retinas of each subject. The Humphrey Visual Field Analyzer was used both to confirm intact full visual fields and to quantify exposure of upper and lower visual fields. On study nights, eyes were dilated, and subjects were exposed to patternless white light for 90 min between 0200 and 0330 under five conditions: (1) full retinal exposure at 200 lux, (2) full retinal exposure at 100 lux, (3) inferior retinal exposure at 200 lux, (4) superior retinal exposure at 200 lux, and (5) a dark-exposed control. Plasma melatonin levels were determined by radioimmunoassay. ANOVA demonstrated a significant effect of exposure condition (F = 5.91, p exposures as well as the inferior retinal exposure; however, superior retinal exposure was significantly less effective in suppressing melatonin. Furthermore, suppression with superior retinal exposure was not significantly different from that of the dark control condition. The results indicate that the inferior retina contributes more to the light-induced suppression of melatonin than the superior retina at the photon dosages tested in this study. Findings suggest a greater sensitivity or denser distribution of photoreceptors in the inferior retina are involved in light detection for the retinohypothalamic tract of humans.

  12. Individual Effect Modifiers of Dust Exposure Effect on Cardiovascular Morbidity.

    Directory of Open Access Journals (Sweden)

    Alina Vodonos

    Full Text Available High concentrations of particulate matter (PM air pollution have been associated with death and hospital admissions due to cardiovascular morbidity. However, it is not clear a whether high levels of non-anthropogenic PM from dust storms constitute a health risk; and b whether these health risks are exacerbated in a particular demographic.This study comprised all patients above 18 years old admitted to Soroka University Medical Center (1000 bed tertiary hospital, Be'er-Sheva, Israel, 2001-2010 with a primary diagnosis of acute coronary syndrome (ACS. Data on meteorological parameters and PM10 (particulate matter <10 μm in aerodiameter were obtained from monitoring stations in the city of Be'er-Sheva. Data were analyzed using a case crossover analysis to examine the effect of dust exposure on hospitalization due to ACS and the interaction with co-morbidities and demographic factors.There were 16,734 hospitalizations due to ACS during the study period. The estimated odds of hospitalization due to ACS was significantly associated with PM10 during non dust storm days at the same day of the exposure (lag0; OR = 1.014 (95%CI 1.001-1.027 for a 10 μg/m3 increase, while a delayed response (lag1 was found during the dust storm days; OR = 1.007 (95%CI 1.002-1.012. The effect size for the dust exposure association was larger for older (above the age of 65, female or Bedouin patients.Exposure to non-anthropogenic PM is associated with cardiovascular morbidity. Health risk associated dust exposure is gender and age specific with older women and Bedouin patients being the most vulnerable groups.

  13. Ambient radiation exposure: measurements and effects

    International Nuclear Information System (INIS)

    A brief review of the available literature, data and reports of various radiation exposure and protection studies and various measurements techniques are presented. A linear quadratic model has been given illustrating the validity of radiation hormesis

  14. Mere exposure and the endowment effect on consumer decision making.

    Science.gov (United States)

    Tom, Gail; Nelson, Carolyn; Srzentic, Tamara; King, Ryan

    2007-03-01

    Previous researchers (e.g., J. A. Bargh, 1992, 2002) demonstrated the importance of nonconscious processes on consumer choice behavior. Using an advertisement, the authors determined the effect of two nonconscious processes--the mere exposure effect, which increases object preference by increasing consumer exposure to an object, and the endowment effect, which increases object valuation by providing consumer possession of an object--on consumer behavior. Although the mere exposure effect and endowment effect did not produce an interaction, they produced independent effects. The endowment effect increased object valuation but not object preference. The mere exposure effect increased object preference but not object valuation. Thus, at the unconscious level, an increase in object preference does not lead to an increase in object valuation, nor does an increase in object valuation lead to an increase in object preference. The authors discuss the importance of developing measures of unconscious process in advertising effectiveness.

  15. Effect of mild diarrhea on tacrolimus exposure

    NARCIS (Netherlands)

    Boekel, G.A.J van; Aarnoutse, R.E.; Heijden, J.J. van der; Hoogtanders, K.E.; Hilbrands, L.B.

    2012-01-01

    BACKGROUND: Diarrhea is a frequent adverse event in patients treated with the combination of tacrolimus and mycophenolate mofetil (MMF). In case of severe diarrhea, the total exposure to tacrolimus can substantially increase, which is reflected in a rise of the predose trough level (C0). In mild dia

  16. Effects of Prenatal Exposure to Phthalates

    Science.gov (United States)

    Johnson, Laurie A.

    2012-01-01

    The purpose of this review of literature is to examine the association of phthalate exposure with development. Phthalates are chemical compounds used in poly-vinyl chloride, PVC; vinyl flooring, cosmetics, shampoo, air fresheners, soft plastic items, intravenous tubing, food packaging and wraps, textiles, paints, cleaning products and detergents.…

  17. Effect of two prednisone exposures on mood and declarative memory.

    Science.gov (United States)

    Brown, E Sherwood; Beard, Laura; Frol, Alan B; Rush, A John

    2006-07-01

    Corticosteroids are essential for life and an integral part of the stress response. However, in excess, corticosteroids can be associated with a variety of effects on the brain including hippocampal atrophy and even neuronal death, mood changes, and declarative memory impairment. The magnitude of mood change in patients receiving prednisone is reportedly associated with previous lifetime corticosteroid exposure, consistent with a sensitization or kindling process whereby greater effects are observed with repeated exposure. To our knowledge, the effect of multiple corticosteroid exposures on mood and memory has not been previously examined prospectively in animals or humans. In this study, 30 human volunteers, with no history of systemic prescription corticosteroid therapy, were given (in random order using a crossover design) two 3-day exposures of prednisone (60 mg/day) and one of identical placebo, with 11-day washouts between each medication exposure. Before and after each 3-day prednisone/placebo exposure, declarative memory was assessed using different versions of the Rey Auditory Verbal Learning Test (RAVLT) to minimize practice or learning effects, while mood was assessed with the 21-item Hamilton Rating Scale for Depression, Young Mania Rating Scale and Internal State Scale. No significant mood changes were found. However, a significant decrease in aspects of RAVLT performance was observed after the first prednisone exposure consistent with a decline in declarative memory performance. The decline in RAVLT performance was significantly smaller after the second prednisone exposure as compared to the initial prednisone exposure. Thus, a second prednisone exposure was associated with an attenuated prednisone-effect on declarative memory. These data suggest tolerance or habituation, rather than sensitization, to prednisone effects on declarative memory during a second exposure. Implications and possible explanations for the findings are discussed.

  18. ACUTE PRENATAL EXPOSURE TO ETHANOL AND SOCIAL BEHAVIOR: EFFECT OF AGE, SEX, AND TIMING OF EXPOSURE

    OpenAIRE

    Mooney, Sandra M.; Varlinskaya, Elena I.

    2010-01-01

    During development of the central nervous system, neurons pass through critical periods of vulnerability to environmental factors. Exposure to ethanol during gastrulation or during neuronal generation results in a permanent reduction in the number of neurons in trigeminal-associated cranial nerve nuclei. Normal functioning of the trigeminal system is required for social behavior, the present study examined the effects of acute prenatal exposure to ethanol on social interactions across ontogen...

  19. Effects of exposure imprecision on estimation of the benchmark dose

    DEFF Research Database (Denmark)

    Budtz-Jørgensen, Esben; Keiding, Niels; Grandjean, Philippe

    2004-01-01

    In regression analysis failure to adjust for imprecision in the exposure variable is likely to lead to underestimation of the exposure effect. However, the consequences of exposure error for determination of safe doses of toxic substances have so far not received much attention. The benchmark......, then the benchmark approach produces results that are biased toward higher and less protective levels. It is therefore important to take exposure measurement error into account when calculating benchmark doses. Methods that allow this adjustment are described and illustrated in data from an epidemiological study...

  20. The Effects of Mere Exposure to Political Advertisements.

    Science.gov (United States)

    Becker, Lee B.; Doolittle, John C.

    Past research into the effects of "exposure" in political advertising indicates that massive "exposure" campaigns alone can show good, and sometimes dramatic, results in elections. This research is partially confirmed by a study of several mass media public relation efforts designed specifically to increase citizen recognition of the name of…

  1. Effects of Impulsive Pile-Driving Exposure on Fishes.

    Science.gov (United States)

    Casper, Brandon M; Carlson, Thomas J; Halvorsen, Michele B; Popper, Arthur N

    2016-01-01

    Six species of fishes were tested under aquatic far-field, plane-wave acoustic conditions to answer several key questions regarding the effects of exposure to impulsive pile driving. The issues addressed included which sound levels lead to the onset of barotrauma injuries, how these levels differ between fishes with different types of swim bladders, the recovery from barotrauma injuries, and the potential effects exposure might have on the auditory system. The results demonstrate that the current interim criteria for pile-driving sound exposures are 20 dB or more below the actual sound levels that result in the onset of physiological effects on fishes.

  2. Mercury Quick Facts: Health Effects of Mercury Exposure

    Science.gov (United States)

    Mercury Quick Facts Health Effects of Mercury Exposure What is Elemental Mercury? Elemental (metallic) mercury is the shiny, silver-gray metal found in thermometers, barometers, and thermostats and other ...

  3. Human Health Effects Associated with Exposure to Toxic Cyanobacteria

    Science.gov (United States)

    Reports of toxic cyanobacteria blooms are increasing worldwide. Warming and eutrophic surface water systems support the development of blooms. We examine the evidence for adverse human health effects associated with exposure to toxic blooms in drinking water, recreational water a...

  4. Effects of tillage practices and carbofuran exposure on small mammals

    Science.gov (United States)

    Albers, P.H.; Linder, G.; Nichols, J.D.

    1990-01-01

    We compared population estimates, body mass, movement, and blood chemistry of small mammals between conventionally tilled and no-till cornfields in Maryland and Pennsylvania to evaluate the effects of tillage practices and carbofuran exposure on small mammals.

  5. Linking exposure to environmental pollutants with biological effects

    DEFF Research Database (Denmark)

    Sørensen, Mette; Autrup, Herman; Møller, Peter;

    2003-01-01

    Exposure to ambient air pollution has been associated with cancer. Ambient air contains a complex mixture of toxics, including particulate matter (PM) and benzene. Carcinogenic effects of PM may relate both to the content of PAH and to oxidative DNA damage generated by transition metals, benzene......, metabolism and inflammation. By means of personal monitoring and biomarkers of internal dose, biologically effective dose and susceptibility, it should be possible to characterize individual exposure and identify air pollution sources with relevant biological effects. In a series of studies, individual......, biological effects of air pollutants appear mainly related to oxidative stress via personal exposure and not to urban background levels. Future developments include personal time-resolved monitors for exposure to ultrafine PM and PM(2.5,) use of GPS, as well as genomics and proteomics based biomarkers....

  6. Exposure and Health Effects of Fungi on Humans.

    Science.gov (United States)

    Baxi, Sachin N; Portnoy, Jay M; Larenas-Linnemann, Désirée; Phipatanakul, Wanda

    2016-01-01

    Fungi are ubiquitous microorganisms that are present in outdoor and indoor environments. Previous research has found relationships between environmental fungal exposures and human health effects. We reviewed recent articles focused on fungal exposure and dampness as risk factors for respiratory disease development, symptoms, and hypersensitivity. In particular, we reviewed the evidence suggesting that early exposure to dampness or fungi is associated with the development of asthma and increased asthma morbidity. Although outdoor exposure to high concentrations of spores can cause health effects such as asthma attacks in association with thunderstorms, most people appear to be relatively unaffected unless they are sensitized to specific genera. Indoor exposure and dampness, however, appears to be associated with an increased risk of developing asthma in young children and asthma morbidity in individuals who have asthma. These are important issues because they provide a rationale for interventions that might be considered for homes and buildings in which there is increased fungal exposure. In addition to rhinitis and asthma, fungus exposure is associated with a number of other illnesses including allergic bronchopulmonary mycoses, allergic fungal sinusitis, and hypersensitivity pneumonitis. Additional research is necessary to establish causality and evaluate interventions for fungal- and dampness-related health effects. PMID:26947460

  7. Probability-summation model of multiple laser-exposure effects.

    Science.gov (United States)

    Menendez, A R; Cheney, F E; Zuclich, J A; Crump, P

    1993-11-01

    A probability-summation model is introduced to provide quantitative criteria for discriminating independent from interactive effects of multiple laser exposures on biological tissue. Data that differ statistically from predictions of the probability-summation model indicate the action of sensitizing (synergistic/positive) or desensitizing (hardening/negative) biophysical interactions. Interactions are indicated when response probabilities vary with changes in the spatial or temporal separation of exposures. In the absence of interactions, probability-summation parsimoniously accounts for "cumulative" effects. Data analyzed using the probability-summation model show instances of both sensitization and desensitization of retinal tissue by laser exposures. Other results are shown to be consistent with probability-summation. The relevance of the probability-summation model to previous laser-bioeffects studies, models, and safety standards is discussed and an appeal is made for improved empirical estimates of response probabilities for single exposures.

  8. Methylmercury exposure and adverse cardiovascular effects in Faroese whalingmen

    DEFF Research Database (Denmark)

    Choi, Anna L; Weihe, Pál; Budtz-Jørgensen, Esben;

    2009-01-01

    BACKGROUND: Methylmercury (MeHg), a worldwide contaminant found in fish and seafood, has been linked to an increased risk of cardiovascular mortality. OBJECTIVE: We examined 42 Faroese whaling men (30-70 years of age) to assess possible adverse effects within a wide range of MeHg exposures from...... consumption of pilot whale meat. METHODS: We assessed exposure levels from mercury analysis of toenails and whole blood (obtained at the time of clinical examination), and a hair sample collected 7 years previously. Outcome measures included heart rate variability (HRV), blood pressure (BP), common carotid...... intima-media thickness (IMT), and brainstem auditory evoked potentials (BAEP). We carried out multiple regression and structural equation model (SEM) analyses to determine the confounder-adjusted effect of mercury exposure. Taking into account correlations among related measures, we categorized exposure...

  9. Pyrethroids: exposure and health effects--an update.

    Science.gov (United States)

    Saillenfait, Anne-Marie; Ndiaye, Dieynaba; Sabaté, Jean-Philippe

    2015-05-01

    Synthetic pyrethroids are present in numerous commercial insecticide formulations and have extensive indoor and outdoor applications worldwide, including agricultural, public, residential, and veterinary usages for pest control. Pyrethroid use has increased continuously in recent years. The aim of this review is to provide updated and comprehensive information on human exposure and potential hazards associated with this class of pesticides. An initial keyword search in the PubMed database was conducted to identify relevant articles. Were taken into considerations only the studies published in the last decade that have assessed exposure and health effects of pyrethroids in human populations. Literature review shows that exposure evaluations increasingly focus on biomonitoring and that a large number of recent epidemiological studies pertain to the effects of pyrethroids on male fertility and prenatal development. The main metabolites of pyrethroids have frequently been detected in urine samples from the general population, confirming widespread exposure of children and adults to one or more pyrethroids. Non-occupational exposure to pyrethroids mainly occurs through ingestion of residues in food, or ingestion of or dermal contact with contaminated house dust or surface-adhering particles, following domestic use. Although clinical features resulting from acute accidental exposure to pyrethroids are well described (e.g., paraesthesiae, and respiratory, eye and skin irritation), information regarding their chronic effects at low concentrations is both limited and controversial. Several recent epidemiological studies have raised concerns about potentially adverse effects on sperm quality and sperm DNA, reproductive hormones, and pregnancy outcomes. Early neurobehavioural development after in utero exposure is discussed. Further research is needed to clarify the possible risks associated with long-term environmental exposure to pyrethroids. PMID:25648288

  10. Depleted uranium exposure and health effects in Gulf War veterans

    OpenAIRE

    Squibb, Katherine S.; McDiarmid, Melissa A.

    2006-01-01

    Health effects stemming from depleted uranium (DU) exposure in a cohort of Gulf War veterans who were in or on US Army vehicles hit by friendly fire involving DU munitions are being carefully monitored through the Baltimore Veterans Affairs (VA) DU Follow-Up Program initiated in 1993. DU exposure in this cohort has been directly measured using inductively coupled plasma-mass spectrometer (ICP-MS) isotopic analysis for DU in urine specimens. Soldiers with embedded DU fragments continue to excr...

  11. Methylmercury Exposure and Adverse Cardiovascular Effects in Faroese Whaling Men

    OpenAIRE

    Choi, Anna Lai; Weihe, Pal; Budtz-Jørgensen, Esben; Jørgensen, Poul J.; Jukka T Salonen; Tuomainen, Tomi-Pekka; Murata, Katsuyuki; Nielsen, Hans Petur; Petersen, Maria Skaalum; Askham, Jórun; Grandjean, Philippe

    2008-01-01

    Background: Methylmercury (MeHg), a worldwide contaminant found in fish and seafood, has been linked to an increased risk of cardiovascular mortality. Objective: We examined 42 Faroese whaling men (30–70 years of age) to assess possible adverse effects within a wide range of MeHg exposures from consumption of pilot whale meat. Methods: We assessed exposure levels from mercury analysis of toenails and whole blood (obtained at the time of clinical examination), and a hair sample collected 7 yea...

  12. Assessment of human exposure effects of nitrous acid

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, T.R.; Kjaergaard, S.K. (University of Aarhus. Institute of Environmental and Occupational Medicine (Denmark)); Brauer, M. (Harvard School of Public Health. Department of Environmental Health, Exposure Assessment and Engineering Program (United States))

    1993-01-01

    The study aimed at an estimation of the relative contribution of nitrous acid to measurable human exposure effects in relation to indoor environments with unvented gas combustion. Fifteen medically examined totally healthy non-smoker adults aged between 22 and 57 years were exposed in a double-blind, balanced design (3x3 latin square) to clean air and nitrous acid (HONO) concentration in an empty 74 m[sup 3] climate chamber. 3 teams of 5 subjects each were randomly exposed and the latin square was selected at random. Each exposure period was 3.5 hours and preceded by a 1 hour base-line pre-exposure measurement period. After 1 hr 40 minutes the subjects exercised for ten minutes on bicycle ergometers in order to increase the uptake of HONO by increasing ventilatory rate 3-4 fold. Workloads were calculated individually and ranged from 21800-34600 kpm/h. During the 10 minutes the test subjects were mouth-breathing to encourage deeper penetration of nitrous acid in the respiratory system so as to induce a mild cooling which would increase their responsiveness to irritants. The amount of deliverable H[sup +] was estimated at 16.350 nmoles with exposure to 395 ppb HONO with subjects breathing at the rate of 5 L min[sup -1]. It was assumed that HONO is efficiently absorbed into the respiratory system. Details are given of the results. Findings were highly variable, largely negative effects of exposure to nitrous acid which appear similiar to results seen in nitrogen dioxide exposure studies. It is concluded to be unlikely that HONO exposures alone can be responsible for exposure misclassification in NO[sub 2] exposure studies. (AB) (52 refs.).

  13. Assessment of human exposure effects of nitrous acid

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, T.R.; Kjaergaard, S.K. [University of Aarhus. Institute of Environmental and Occupational Medicine (Denmark); Brauer, M. [Harvard School of Public Health. Department of Environmental Health, Exposure Assessment and Engineering Program (United States)

    1993-01-01

    The study aimed at an estimation of the relative contribution of nitrous acid to measurable human exposure effects in relation to indoor environments with unvented gas combustion. Fifteen medically examined totally healthy non-smoker adults aged between 22 and 57 years were exposed in a double-blind, balanced design (3x3 latin square) to clean air and nitrous acid (HONO) concentration in an empty 74 m{sup 3} climate chamber. 3 teams of 5 subjects each were randomly exposed and the latin square was selected at random. Each exposure period was 3.5 hours and preceded by a 1 hour base-line pre-exposure measurement period. After 1 hr 40 minutes the subjects exercised for ten minutes on bicycle ergometers in order to increase the uptake of HONO by increasing ventilatory rate 3-4 fold. Workloads were calculated individually and ranged from 21800-34600 kpm/h. During the 10 minutes the test subjects were mouth-breathing to encourage deeper penetration of nitrous acid in the respiratory system so as to induce a mild cooling which would increase their responsiveness to irritants. The amount of deliverable H{sup +} was estimated at 16.350 nmoles with exposure to 395 ppb HONO with subjects breathing at the rate of 5 L min{sup -1}. It was assumed that HONO is efficiently absorbed into the respiratory system. Details are given of the results. Findings were highly variable, largely negative effects of exposure to nitrous acid which appear similiar to results seen in nitrogen dioxide exposure studies. It is concluded to be unlikely that HONO exposures alone can be responsible for exposure misclassification in NO{sub 2} exposure studies. (AB) (52 refs.).

  14. Contaminant Exposure and Effects--Terrestrial Vertebrates

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Biomonitoring of Environmental Status and Trends (BEST) program of the Department of Interior is focused to identify and understand effects of contaminant...

  15. Health Effects Related to Wind Turbine Noise Exposure

    DEFF Research Database (Denmark)

    Schmidt, Jesper Hvass; Klokker, Mads

    2014-01-01

    . OBJECTIVE: This review was conducted systematically with the purpose of identifying any reported associations between wind turbine noise exposure and suspected health-related effects. DATA SOURCES: A search of the scientific literature concerning the health-related effects of wind turbine noise......, to be a tolerable level of around LAeq of 35 dB. Of the many other claimed health effects of wind turbine noise exposure reported in the literature, however, no conclusive evidence could be found. Future studies should focus on investigations aimed at objectively demonstrating whether or not measureable health-related......BACKGROUND: Wind turbine noise exposure and suspected health-related effects thereof have attracted substantial attention. Various symptoms such as sleep-related problems, headache, tinnitus and vertigo have been described by subjects suspected of having been exposed to wind turbine noise...

  16. The effects of proton exposure on neurochemistry and behavior

    Science.gov (United States)

    Shukitt-Hale, B.; Szprengiel, A.; Pluhar, J.; Rabin, B. M.; Joseph, J. A.

    2004-01-01

    Future space missions will involve long-term travel beyond the magnetic field of the Earth, where astronauts will be exposed to radiation hazards such as those that arise from galactic cosmic rays. Galactic cosmic rays are composed of protons, α particles, and particles of high energy and charge (HZE particles). Research by our group has shown that exposure to HZE particles, primarily 600 MeV/n and 1 GeV/n 56Fe, can produce significant alterations in brain neurochemistry and behavior. However, given that protons can make up a significant portion of the radiation spectrum, it is important to study their effects on neural functioning and on related performance. Therefore, these studies examined the effects of exposure to proton irradiation on neurochemical and behavioral endpoints, including dopaminergic functioning, amphetamine-induced conditioned taste aversion learning, and spatial learning and memory as measured by the Morris water maze. Male Sprague-Dawley rats received a dose of 0, 1.5, 3.0 or 4.0 Gy of 250 MeV protons at Loma Linda University and were tested in the different behavioral tests at various times following exposure. Results showed that there was no effect of proton irradiation at any dose on any of the endpoints measured. Therefore, there is a contrast between the insignificant effects of high dose proton exposure and the dramatic effectiveness of low dose (<0.1 Gy) exposures to 56Fe particles on both neurochemical and behavioral endpoints.

  17. Frequency and collective effective dose equivalent of medical exposures

    International Nuclear Information System (INIS)

    According to ICRP recommendation, medical exposure refers to the intentional exposure of patients for diagnostic and therapeutic purposes, and to the exposures resulting from the artificial replacement of body organs or functions. Since the objective of radiotherapy is to give a large amount of radiation dose to the patient to kill cancer cells, neither individual nor collective effective doses are directly relevant for comparisons with doses from other sources, not even with diagnostic procedures. For this reason, in present report, therapeutic uses of radiations and radiopharmaceuticals are not included in the medical exposures. Medical exposures in Japan have been investigated by the nationwide surveys on the type and the frequency of radiological procedures and by the dose determinations with phantom experiments or calculations since 1960. Present report reviews the frequency of diagnostic radiological procedures and the collective effective dose equivalents from these procedures, and excess deaths from the medical exposures in Japan. In 1986, the number of X-ray diagnostic examinations was estimated to be about 1.41 x 108. The preliminary result in 1991 shows the number will be about 1.8 x 108. The resultant collective effective dose equivalent from X-ray diagnosis in 1986 was about 1.84 x 105 person Sv. Consequently per Caput mean effective dose equivalent was about 1.48 mSv/person in 1986. The total collective effective dose equivalent from all the diagnostic radiological procedures in Japan was estimated to be about 2.96 x 105 person Sv/year. per Caput mean effective dose equivalent from the total diagnostic radiological procedures in Japan was evaluated to be about 2.3 mSv/year. This value may be comparable to the mean annual effective dose equivalent received from natural radiations for the worldwide population. Mean effective dose equivalent per diagnostic radiological examination was calculated to be about 1.00 mSv/examination. (author)

  18. Dose-effect relationship in radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Oberhausen, E.

    1983-01-01

    As criterion for the evaluation of risk in connection with nuclear accidents the diminishing of life expectance is assumed. This would allow a better weighting of the different detriments. The possible dose-effect relations for the different detriments caused by radiation are discussed. Some models for a realistic evaluation of the different radiation detriments are proposed.

  19. Exposure and effectiveness of phytosterol/-stanol-enriched margarines

    NARCIS (Netherlands)

    Jong, N.; Zuur, A.; Wolfs, M.C.J.; Wendel-Vos, G.C.W.; Raaij, van J.M.A.; Schuit, A.J.

    2007-01-01

    Background: Studies on effectiveness of phytosterol/-stanol-enriched margarines in the community have received low priority. For postlaunch monitoring purposes including risk-benefit analyses, it is needed to investigate both exposure and effectiveness of these margarines. Objective: To study the us

  20. Physiological effects after exposure to heat : A brief literature review

    NARCIS (Netherlands)

    Bogerd, C.P.; Daanen, H.A.M.

    2011-01-01

    Many employees are exposed to heat stress during their work. Although the direct effects of heat are well reported, the long term physiological effects occurring after heat exposure are hardly described. The present manuscript addresses these issues in the form of a brief literature review. Repeated

  1. Effects of exposure to electromagnetic fields (microwaves) on mammalian pregnancy

    International Nuclear Information System (INIS)

    Women soldiers account now for nearly 10 % of the NATO forces. Some studies have alleged that exposure to microwaves may result in pregnancy mishaps. We have tried to assess what was the risk. A lot of studies were conducted on non mammalian species: birds, sea urchins, worms and insects. Extrapolation to the mammals is subject to caution due to the protective effect of intrauterine development. We reviewed the literature dealing only with mammals. Even if some discrepancy persists, it seems that the presence or the absence of thermic effect is essential in order to estimate the risk. Reduced birth weight and increased rate of miscarriage were the most common findings when the exposure reached a thermic effect. In the majority of the studies, non thermic exposure had no impact on pregnancy outcome. (authors)

  2. UV dose-effect relationships and current protection exposure standards

    International Nuclear Information System (INIS)

    In this paper we have attempted to quantify the health effects in man of uv-radiation exposure of wavelengths from 240 nm to 320 nm. Exposure to uv in this region could result in the formation of skin cancer or premature aging in man. The induction of cancer by uv radiation results from changes in genetic material. We have used the DNA action spectrum coupled with the uv skin cancer data available in the literature to derive the dose-effect relationships. The results are compared against the current uv protection standards

  3. Exposure assessment in studies on health effects of traffic exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Setaelae, S. [Association for the Pulmonary Disabled, Helsinki (Finland); Jaakkola, J.J.K. [Helsinki Univ. (Finland). Dept. of Public Health

    1995-12-31

    A main source of outdoor air pollution is road traffic, which produces a complex mixture of nitrogen oxides, carbon monoxide, volatile hydrocarbons, airborne particles and some other compounds. Traffic exhaust affects also the concentrations of ozone and other photo chemical oxidants. In earlier studies those components have had remarkable health effects. Several studies on occupational exposure to automobile exhaust have been published and several studies have been observed an association between both outdoor and indoor pollutant levels and health outcomes. However, there are only a few epidemiological studies in which traffic exhaust, a complex mixture, has been studied in its entirety. During recent years, interesting epidemiological studies of the health effects of this complex mixture have been published. Human exposure assessment for traffic exhaust can be categorized according to the environment of exposure (indoors, outdoors, in-traffic) or to the method of exposure assessment (direct or indirect methods). In this presentation the methods are further categorized into (1) traffic activity, (2) air concentration measurements, and (3) dispersion models, in order to better understand the advantages and disadvantages of different approaches. The objective of this presentation is to make a critical review of exposure assessments in the epidemiological studies on health effects of traffic exhaust. (author)

  4. Creation of a crystalline lens radiation exposure defense cover and the effect of radiation exposure decrease on neuro-interventions

    International Nuclear Information System (INIS)

    A variety of radiation hazards resulting from interventional radiology (IVR) have been reported in recent years. Particularly affected are the skin and the crystalline lens, with their high radiation sensitivity. During neurological interventions, the radiological technologist should consider decreasing radiation exposure. We found exposure projections where the exposure dose became a radiation hazard for the crystalline lens, and examined an efficient method of cover for the exposure projections used for neurological interventions. The exposure projection for maximum crystalline lens radiation exposure was a lateral projection. In the crystalline lens the maximum exposure to radiation was on the X-ray tube side. The method of defense adopted was that of installing a lead plate of the appropriate shape on the surface of the X-ray tube collimator. In other exposure projections, this cover did not become a redundant shadow. With the cover that was created, the X-ray side crystalline lens lateral projection could be defended effectively. (author)

  5. Effect of exposure delay of concrete into aggressive environment

    Science.gov (United States)

    Abimouloud, Youcef; Kriker, Abdelouahed

    2016-07-01

    Some regions in the world suffered since several years from environmental problems such as underground level water rising. Water table effects durability of concrete implantation in the underground by the ease of luckless chemical elements ingress mainly through concrete the foundations of structures such as sulfate, chloride, and acids. For that reason a lot of foundations structures were made with SRPC (sulfate resisting Portland cement). This study is a contribution to assess the effect of exposure delay of concrete into aggressive fields, as a kind of cure which protects concrete from aggressive factors and allows it to acquire the needed strength. The study has shown that concrete exposure delay into aggressive environment is not a kind of cure mainly for concrete made with SRPC. Concrete with SRPC immediately exposed to aggressive environment shows a better mechanical resistance than concrete that has known exposure delay.

  6. Effects of Ambient Air Pollution Exposure on Olfaction: A Review

    Science.gov (United States)

    Ajmani, Gaurav S.; Suh, Helen H.; Pinto, Jayant M.

    2016-01-01

    Background: Olfactory dysfunction affects millions of people worldwide. This sensory impairment is associated with neurodegenerative disease and significantly decreased quality of life. Exposure to airborne pollutants has been implicated in olfactory decline, likely due to the anatomic susceptibility of the olfactory nerve to the environment. Historically, studies have focused on occupational exposures, but more recent studies have considered effects from exposure to ambient air pollutants. Objectives: To examine all relevant human data evaluating a link between ambient pollution exposure and olfaction and to review supporting animal data in order to examine potential mechanisms for pollution-associated olfactory loss. Methods: We identified and reviewed relevant articles from 1950 to 2015 using PubMed and Web of Science and focusing on human epidemiologic and pathophysiologic studies. Animal studies were included only to support pertinent data on humans. We reviewed findings from these studies evaluating a relationship between environmental pollutant exposure and olfactory function. Results: We identified and reviewed 17 articles, with 1 additional article added from a bibliography search, for a total of 18 human studies. There is evidence in human epidemiologic and pathologic studies that increased exposure to ambient air pollutants is associated with olfactory dysfunction. However, most studies have used proxies for pollution exposure in small samples of convenience. Human pathologic studies, with supporting animal work, have also shown that air pollution can contact the olfactory epithelium, translocate to the olfactory bulb, and migrate to the olfactory cortex. Pollutants can deposit at each location, causing direct damage and disruption of tissue morphology or inducing local inflammation and cellular stress responses. Conclusions: Ambient air pollution may impact human olfactory function. Additional studies are needed to examine air pollution

  7. Health effects of non-occupational exposure to oil extraction.

    Science.gov (United States)

    O'Callaghan-Gordo, Cristina; Orta-Martínez, Martí; Kogevinas, Manolis

    2016-01-01

    Oil extraction may cause extensive environmental impact that can affect health of populations living in surrounding areas. Large populations are potentially exposed to oil extraction related contamination through residence in areas where oil extraction is conducted, especially in low and middle income countries (LMICs). Health effects among people residentially exposed to upstream oil industry contaminants have been poorly studied. Health effects of exposure to oil related contamination have been mainly studied among cleanup workers after oil spills from tankers or offshore platforms.In this paper we aim to identify the type and extension of residential exposures related to oil extraction activities and to comment on the few health studies available. We estimated that 638 million persons in LMICs inhabit rural areas close to conventional oil reservoirs. It is relevant to specifically study people residentially exposed to upstream oil industry for the following reasons: First, persons are exposed during long periods of time to oil related contamination. Second, routes of exposure differ between workers and people living close to oil fields, who can be exposed by ingestion of contaminated waters/foods and by dermal contact with contaminated water and/or land during daily activities (e.g. bathing, agricultural activities, etc.). Third, individuals potentially more susceptible to the effect of oil related contamination and not normally occupationally exposed, such as infants, children, pregnant women, elderly or people with previous health conditions, are also exposed.There are few papers studying the potential health effects of residential exposure to oil related contamination, and most of them share important limitations. There is a need for more research through the conduct of methodologically robust studies in exposed populations worldwide. Despite the difficulties in the conduct of studies in remote areas, novel approaches, such as measurement of individual

  8. Resilient Coping Moderates the Effect of Trauma Exposure on Depression.

    Science.gov (United States)

    Sinclair, Vaughn G; Wallston, Kenneth A; Strachan, Eric

    2016-08-01

    Posttraumatic depression rates are increasing in the United States, and there is a great need to identify malleable factors that could moderate posttraumatic depression levels. The purpose of this study was to examine whether resilient coping moderates the effects of trauma exposure on depression, while controlling for neuroticism-an established predictor of depressive symptoms. This study used data from 3,734 pairs of twins from the community-based University of Washington Twin Registry. Each twin pair was randomized with twin A in one subsample and twin B in the second subsample. The four-item Brief Resilient Coping Scale measured resilient coping. The two-item Patient Health Questionnaire measured depression. Multiple linear regression analyses were performed on each subsample, controlling for neuroticism. In addition to significant effects of neuroticism and trauma exposure on depression (p resilient coping and trauma exposure on depression was significant in both subsamples (p High levels of resilient coping were associated with lower depression scores in the context of previous trauma exposure. Individuals high in resilient coping who experienced significant life traumas were less depressed after trauma exposure, even after controlling for neuroticism. Because coping skills may be learned, interventions that teach resilient coping to individuals with traumatic histories merit investigation. © 2016 Wiley Periodicals, Inc. PMID:27176758

  9. Effective biological dose from occupational exposure during nanoparticle synthesis

    International Nuclear Information System (INIS)

    Nanomaterial and nanotechnology safety require the characterization of occupational exposure levels for completing a risk assessment. However, equally important is the estimation of the effective internal dose via lung deposition, transport and clearance mechanisms. An integrated source-to-biological dose assessment study is presented using real monitoring data collected during nanoparticle synthesis. Experimental monitoring data of airborne exposure levels during nanoparticle synthesis of CaSO4 and BiPO4 nanoparticles in a research laboratory is coupled with a human lung transport and deposition model, which solves in an Eulerian framework the general dynamic equation for polydisperse aerosols using particle specific physical-chemical properties. Subsequently, the lung deposition model is coupled with a mathematical particle clearance model providing the effective biological dose as well as the time course of the biological dose build-up after exposure. The results for the example of BiPO4 demonstrate that even short exposures throughout the day can lead to particle doses of 1.10·E+08/(kg-bw·8h-shift), with the majority accumulating in the pulmonary region. Clearance of particles is slow and is not completed within a working shift following a 1 hour exposure. It mostly occurs via macrophage activity in the alveolar region, with small amounts transported to the interstitium and less to the lymph nodes.

  10. Effective biological dose from occupational exposure during nanoparticle synthesis

    Science.gov (United States)

    Demou, Evangelia; Tran, Lang; Housiadas, Christos

    2009-02-01

    Nanomaterial and nanotechnology safety require the characterization of occupational exposure levels for completing a risk assessment. However, equally important is the estimation of the effective internal dose via lung deposition, transport and clearance mechanisms. An integrated source-to-biological dose assessment study is presented using real monitoring data collected during nanoparticle synthesis. Experimental monitoring data of airborne exposure levels during nanoparticle synthesis of CaSO4 and BiPO4 nanoparticles in a research laboratory is coupled with a human lung transport and deposition model, which solves in an Eulerian framework the general dynamic equation for polydisperse aerosols using particle specific physical-chemical properties. Subsequently, the lung deposition model is coupled with a mathematical particle clearance model providing the effective biological dose as well as the time course of the biological dose build-up after exposure. The results for the example of BiPO4 demonstrate that even short exposures throughout the day can lead to particle doses of 1.10·E+08#/(kg-bw·8h-shift), with the majority accumulating in the pulmonary region. Clearance of particles is slow and is not completed within a working shift following a 1 hour exposure. It mostly occurs via macrophage activity in the alveolar region, with small amounts transported to the interstitium and less to the lymph nodes.

  11. Exposure to multiple environmental agents and their effect

    NARCIS (Netherlands)

    Koppe, Janna G.; Bartonova, Alena; Bolte, Gabriele; Bistrup, Marie Louise; Busby, Chris; Butter, Maureen; Dorfman, Paul; Fucic, Aleksandra; Gee, David; van den Hazel, Peter; Howard, Vyvyan; Kohlhuber, Martina; Leijs, Marike; Lundqvist, Christofer; Moshammer, Hanns; Naginiene, Rima; Nicolopoulou-Stamati, Polyxeni; Ronchetti, Roberto; Salines, Georges; Schoeters, Greet; ten Tusscher, Gavin; Wallis, Max K.; Zuurbier, Moniek

    2006-01-01

    Introduction: All children are exposed to multiple physical, chemical and biological challanges that can result in adverse health effects before and after birth. In this context, the danger of multiple exposures cannot be assessed from a single-chemical approach as used in classical toxicology. Aim:

  12. Prevalence and Effects of Child Exposure to Domestic Violence.

    Science.gov (United States)

    Fantuzzo, John W.; Mohr, Wanda K.

    1999-01-01

    Discusses the limitations of current databases documenting the prevalence and effects of child exposure to domestic violence and describes a model for the collection of reliable and valid prevalence data, the Spousal Assault Replication Program, which uses data collected by the police and university researchers. (SLD)

  13. Effect of air-conditioner exposure on semen quality

    Institute of Scientific and Technical Information of China (English)

    Min-LiLu; Jun-QingWu; Qiu-YingYang; Wei-JinZhou; Er-ShengGao

    2004-01-01

    Aim: To investigate the effect of air-conditioner exposure on semen quality. Methods: The data came from the healthy male volunteers, aged 22 to 30 years, who went to centers for maternity and children health for premarital physical examination in Shanghai,Henan, Zbejiang and Hebei from December 1998 to February 2000.

  14. Neuropsychological Effects of Second Language Exposure in Down Syndrome

    Science.gov (United States)

    Edgin, J. O.; Kumar, A.; Spano, G.; Nadel, L.

    2011-01-01

    Background: While it has been common practice to discourage second language learning in neurodevelopmental disorders involving language impairment, little is known about the effects of second language exposure (SLE) on broader cognitive function in these children. Past studies have not found differences on language tasks in children with Down…

  15. Adolescent Initiation of Drug Use: Effects of Prenatal Cocaine Exposure

    Science.gov (United States)

    Richardson, Gale A.; Larkby, Cynthia; Goldschmidt, Lidush; Day, Nancy L.

    2013-01-01

    Objective: To investigate the direct effects of prenatal cocaine exposure (PCE) on adolescent drug use, while controlling for other predictors of adolescent use. Method: Data are from a longitudinal study of PCE in which women and their offspring were assessed throughout childhood. Adolescents were interviewed at 15 years about their age at…

  16. Effects of bilateral and unilateral laser ocular exposure in humans

    Science.gov (United States)

    Stamper, David A.; Lund, David J.; Molchany, Jerome W.; Stuck, Bruce E.

    2003-06-01

    INTRODUCTION: The amount of visual disruption experienced by individuals exposed to a visible laser source at levels, which are below that, which will damage the cornea or retina will depend on laser exposure parameters and task demands. Previous work has evaluated the effects of wavelength, duration, ambient light level, and target variables. One factor that has not received attention is monocular vs. binocular exposure. Whether the exposure is monocular or binocular may alter pupil dynamics, eyelid closure, and ultimately affect visual performance. METHODS: In this study 10 males and females were exposed to 0.1 and 3.0 sec laser flashes while tracking a dynamic target at 0.28 deg/sec through a scope that was capable of selecting binocular or monocular viewing. Bright (430 nits) and dawn/dusk (4.3 nits) ambient light conditions were simulated using ND filters. A collimated 514.5 nm argon laser beam produced corneal radiant exposures of 0.16 and 1.0 mJ/cm2 for the 0.1 and 3.0 sec conditions respectively. For each flash trial total time off target and maximum absolute error scores were calculated. Eye response (changes in pupil diameter) was assessed by evaluation of videotape from an IR eye camera. Tracking error scores (total time off target) were calculated for each flash trial. RESULTS: Analysis of variance results for the total time off target scores found all three main factors (light level, exposure duration, and monocular/binocular to be significant. Earlier studies have previously shown dawn/dusk flash exposures be more disruptive than bright light trials. Also three sec exposures were more disruptive than one sec exposures. Finally, monocular exposures produced significantly higher error scores than did binocular exposures. For the pupil diameters the post-flash diameters were significantly smaller that the pre-flash diameters and monocular diameters larger that binocular pupil sizes. SUMMARY: The Total Time Off Target error scores for the monocular

  17. The Effect of Uncertainty in Exposure Estimation on the Exposure-Response Relation between 1,3-Butadiene and Leukemia

    Directory of Open Access Journals (Sweden)

    George Maldonado

    2009-09-01

    Full Text Available Abstract: In a follow-up study of mortality among North American synthetic rubber industry workers, cumulative exposure to 1,3-butadiene was positively associated with leukemia. Problems with historical exposure estimation, however, may have distorted the association. To evaluate the impact of potential inaccuracies in exposure estimation, we conducted uncertainty analyses of the relation between cumulative exposure to butadiene and leukemia. We created the 1,000 sets of butadiene estimates using job-exposure matrices consisting of exposure values that corresponded to randomly selected percentiles of the approximate probability distribution of plant-, work area/job group-, and year specific butadiene ppm. We then analyzed the relation between cumulative exposure to butadiene and leukemia for each of the 1,000 sets of butadiene estimates. In the uncertainty analysis, the point estimate of the RR for the first non zero exposure category (>0–<37.5 ppm-years was most likely to be about 1.5. The rate ratio for the second exposure category (37.5–<184.7 ppm-years was most likely to range from 1.5 to 1.8. The RR for category 3 of exposure (184.7–<425.0 ppm-years was most likely between 2.1 and 3.0. The RR for the highest exposure category (425.0+ ppm-years was likely to be between 2.9 and 3.7. This range off RR point estimates can best be interpreted as a probability distribution that describes our uncertainty in RR point estimates due to uncertainty in exposure estimation. After considering the complete probability distributions of butadiene exposure estimates, the exposure-response association of butadiene and leukemia was maintained. This exercise was a unique example of how uncertainty analyses can be used to investigate and support an observed measure of effect when occupational exposure estimates are employed in the absence of direct exposure measurements.

  18. Health effects of airborne exposures from concentrated animal feeding operations

    DEFF Research Database (Denmark)

    Heederik, Dick; Sigsgaard, Torben; Thorne, Peter S;

    2006-01-01

    of Concentrated Animal Feeding Operations: Anticipating Hazards-Searching for Solutions, concluded that there is a great need to evaluate health effects from exposures to the toxic gases, vapors, and particles emitted into the general environment by CAFOs. Research should focus not only on nuisance and odors......Toxic gases, vapors, and particles are emitted from concentrated animal feeding operations (CAFOs) into the general environment. These include ammonia, hydrogen sulfide, carbon dioxide, malodorous vapors, and particles contaminated with a wide range of microorganisms. Little is known about...... the health risks of exposure to these agents for people living in the surrounding areas. Malodor is one of the predominant concerns, and there is evidence that psychophysiologic changes may occur as a result of exposure to malodorous compounds. There is a paucity of data regarding community adverse health...

  19. Minors' exposure to online pornography: prevalence, motivations, contents and effects

    Directory of Open Access Journals (Sweden)

    Eva González-Ortega

    2013-05-01

    Full Text Available Since Internet has made pornographic materials more available, there is a need for more research on the characteristics and implications of children's and adolescents' exposure to such materials. This study examined the prevalence and extent of minors' exposure to online pornography, the reasons for exposure, the types of images seen and the strong effects of exposure, as reported by college students. We used an online survey to collect retrospective reports of a sample of 494 students of the University of Salamanca. Results show that 63% of boys and 30% of girls were exposed to online pornography during adolescence. Boys are more likely to have ever been exposed for more than 30 minutes. Boys are more likely to report deliberate consumption and sexual excitement seeking, whereas girls are more likely to report involuntary exposure. Both genders remember viewing a variety of images, including contents of bondage, child pornography and rape. One in six of exposed participants remember strong reactions. While more boys report sexual excitement and masturbation, more girls report avoidance, disgust or concern.

  20. At the Roots of Product Placement: The Mere Exposure Effect

    Directory of Open Access Journals (Sweden)

    Stefano Ruggieri

    2013-05-01

    Full Text Available The present study aims to analyze the effect of product placement on attitude change and takes into consideration psychological models of the mere exposure effect. A sample of high school students watched an excerpt from two widely-distributed movies in which several products were shown by using the technique known as product placement. The results indicate that students who saw the commercial brand liked the products more than those who didn’t see it. This effect, in line with the literature on the product placement effect, seems to be independent from the recognition of the brand in the movie excerpt. This study also shows that, in the high involvement condition, one exposure is enough to produce a positive attitude toward the brand.

  1. Exposure assessment strategies for crystalline silica health effects

    Energy Technology Data Exchange (ETDEWEB)

    Lippman, M. [New York University Medical Center, Tuxedo, NY (United States). Nelson Institute of Environmental Medicine

    1995-12-01

    Occupational exposure to dusts containing crystalline silica has long been associated with the induction of silicosis, a focal fibrosis of the pulmonary parenchyma. Since only the dust that could penetrate to the gas exchange region of the lung, defined as respirable dust, could produce a pneumoconiosis such as silicosis, size-selective respirable dust inlets were developed for air samplers to restrict the dust analyses to the respirable fraction of the airborne dust. Analyses of respirable dust are reported in terms of mass concentration, although a case can be made for associating the hazard more closely with the surface area of the dust. The hazards associated with inhaling crystalline silica within dust mixtures also depend on the properties of the coconstituents of the mixed aerosol, as documented in epidemiological studies on miners. Other considerations affecting exposure assessment strategies are concerns about diseases other than silicosis that may be caused by exposure to dusts containing crystalline silica. These include bronchitis and lung and stomach cancer, which may be related to the thoracic fraction of the airborne dust. Technical issues affecting the selection of size-selective samplers, their siting, sampling periods, flow rates, and sampling schedules can all be important in evaluating the effectiveness of an exposure assessment strategy. Changes in the work environment also need to be considered to the extent that they may affect airborne exposure and dose to target tissues in the lungs. Automation and production rate changes can alter both dust concentrations and size distributions, as well as respiratory patterns of the workers and their proximity to dust sources. These factors can also influence optimal placement of dust samplers and/or monitors. These and other factors are critically reviewed in terms of current and future exposure assessment strategies. 47 refs., 9 figs., 2 tabs.

  2. Studies of effects of radiation exposure on children

    International Nuclear Information System (INIS)

    This review describes the title subject from the aspect of age difference in humans and experimental animals. Epidemiological studies on A-bomb survivors have revealed that the effects are dependent on the dose, sex, age at exposure and attained age after the exposure. Analysis of the survivor cohort shows that the younger is the age at exposure, the higher the risk of cancer death at an attained age. However, the risk is suggested small and insignificant regardless to the age of exposure at the low dose 0.005-0.5 Gy. The risk of carcinogenesis at the attained age 50 y of exposed children is 1.7 while that of exposed fetuses, 0.42. There are no confounding factors in animal experiments. Risks of carcinogenesis and life-span reduction have been found the highest in the exposed mouse neonate (0-7 days old). In authors' studies with gamma-ray, it is shown that females are more susceptible, the risk is the highest in 1 week old infants and is the lowest in fetuses at 17 days after gestation at <1 Gy dose. That the susceptible age to cancer formation differs on the organ is also shown, where at exposure to the late phase fetuses/neonates/infants, increased incidence of cancers thereafter is seen in the brain, kidney, liver, mammary gland, lung, gut and T-lymphocytes in contrast to adults in which the lung cancer and marrow leukemia are major. Carcinogenic radiation response of infant seems different from that of adult: after exposure, adult gut cells die due to the apoptosis through p53-Noxa-caspase pathway but at the developing age, p53-p21 pathway is activated leading to the arrest of cell cycle, resulting in survival of DNA-injured cells. Studies on the age difference of cancer formation is conceivably important for elucidation of radiation carcinogenesis for radiation protection and risk reduction. (T.T.)

  3. Long-term effects of radiation exposure on health.

    Science.gov (United States)

    Kamiya, Kenji; Ozasa, Kotaro; Akiba, Suminori; Niwa, Ohstura; Kodama, Kazunori; Takamura, Noboru; Zaharieva, Elena K; Kimura, Yuko; Wakeford, Richard

    2015-08-01

    Late-onset effects of exposure to ionising radiation on the human body have been identified by long-term, large-scale epidemiological studies. The cohort study of Japanese survivors of the atomic bombings of Hiroshima and Nagasaki (the Life Span Study) is thought to be the most reliable source of information about these health effects because of the size of the cohort, the exposure of a general population of both sexes and all ages, and the wide range of individually assessed doses. For this reason, the Life Span Study has become fundamental to risk assessment in the radiation protection system of the International Commission on Radiological Protection and other authorities. Radiation exposure increases the risk of cancer throughout life, so continued follow-up of survivors is essential. Overall, survivors have a clear radiation-related excess risk of cancer, and people exposed as children have a higher risk of radiation-induced cancer than those exposed at older ages. At high doses, and possibly at low doses, radiation might increase the risk of cardiovascular disease and some other non-cancer diseases. Hereditary effects in the children of atomic bomb survivors have not been detected. The dose-response relation for cancer at low doses is assumed, for purposes of radiological protection, to be linear without a threshold, but has not been shown definitively. This outstanding issue is not only a problem when dealing appropriately with potential health effects of nuclear accidents, such as at Fukushima and Chernobyl, but is of growing concern in occupational and medical exposure. Therefore, the appropriate dose-response relation for effects of low doses of radiation needs to be established. PMID:26251392

  4. Health effects assessment of chemical exposures: ARIES methodology

    Energy Technology Data Exchange (ETDEWEB)

    Sierra, L; Montero, M.; Rabago, I.; Vidania, R.

    1995-07-01

    In this work, we present ARIES* update: a system designed in order to facilitate the human health effects assessment produced by accidental release of toxic chemicals. The first version of ARIES was developed in relation to 82/501/EEC Directive about mayor accidents in the chemical industry. So, the first aim was the support of the effects assessment derived for the chemicals included into this directive. From this establishment, it was considered acute exposures for high concentrations. In this report, we present the actual methodology for considering other type of exposures, such as environmental and occupational. Likewise other versions, the methodology comprises two approaches: quantitative and qualitative assessments. Quantitative assessment incorporates the mathematical algorithms useful to evaluate the effects produced by the most important routes of exposure: inhalation, ingestion, eye contact and skin absorption, in a short, medium and long term. It has been included models that realizes an accurate quantification of doses, effects,... and so on, such as simple approaches when the available information is not enough. Qualitative assessment, designed in order to complement or replace the previous one, is incorporated into an informatics system, developed in Clipper. It executes and displays outstanding and important toxicological information of about 100 chemicals. This information comes from ECDIN (Environmental Chemicals Data and Information Network) database through a collaboration with JRC-ISPRA working group. (Author) 24 refs.

  5. Health effects assessment of chemical exposures: ARIES methodology

    International Nuclear Information System (INIS)

    In this work, we present ARIES* update: a system designed in order to facilitate the human health effects assessment produced by accidental release of toxic chemicals. The first version of ARIES was developed in relation to 82/501/EEC Directive about mayor accidents in the chemical industry. So, the first aim was the support of the effects assessment derived for the chemicals included into this directive. From this establishment, it was considered acute exposures for high concentrations. In this report, we present the actual methodology for considering other type of exposures, such as environmental and occupational. Likewise other versions, the methodology comprises two approaches: quantitative and qualitative assessments. Quantitative assessment incorporates the mathematical algorithms useful to evaluate the effects produced by the most important routes of exposure: inhalation, ingestion, eye contact and skin absorption, in a short, medium and long term. It has been included models that realizes an accurate quantification of doses, effects,... and so on, such as simple approaches when the available information is not enough. Qualitative assessment, designed in order to complement or replace the previous one, is incorporated into an informatics system, developed in Clipper. It executes and displays outstanding and important toxicological information of about 100 chemicals. This information comes from ECDIN (Environmental Chemicals Data and Information Network) database through a collaboration with JRC-ISPRA working group. (Author) 24 refs

  6. Health Effects of Exposure to Low Dose of Radiation

    International Nuclear Information System (INIS)

    Human beings are exposed to natural radiation from external sources include radionuclides in the earth and cosmic radiation, and by internal radiation from radionuclides, mainly uranium and thorium series, incorporated into the body. Living systems have adapted to the natural levels of radiation and radioactivity. But some industrial practices involving natural resources enhance these radionuclides to a degree that they may pose risk to humans and the environment if they are not controlled. Biological effects of ionizing radiation are the outcomes of physical and chemical processes that occur immediately after the exposure, then followed by biological process in the body. These processes will involve successive changes in the molecular, cellular, tissue and whole organism levels. Any dose of radiation, no matter how small, may produce health effects since even a single ionizing event can result in DNA damage. The damage to DNA in the nucleus is considered to be the main initiating event by which radiation causes damage to cells that results in the development of cancer and hereditary disease. It has also been indicated that cytogenetic damage can occur in cells that receive no direct radiation exposure, known as bystander effects. This paper reviews health risks of low dose radiation exposure to human body causing stochastic effects, i.e. cancer induction in somatic cells and hereditary disease in genetic cells. (author)

  7. Effects in Plant Populations Resulting from Chronic Radiation Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Geras' kin, Stanislav A.; Volkova, Polina Yu.; Vasiliyev, Denis V.; Dikareva, Nina S.; Oudalova, Alla A. [Russian Institute of Agricultural Radiology and Agroecology, 249032, Obninsk (Russian Federation)

    2014-07-01

    Human industrial activities have left behind a legacy of ecosystems strongly impacted by a wide range of contaminants, including radionuclides. Phyto-toxic effects of acute impact are well known, but the consequences of long-term chronic exposure to low pollutant concentrations is neither well understood nor adequately included in risk assessments. To understand effects of real-world contaminant exposure properly we must pay attention to what is actually going on in the field. However, for many wildlife groups and endpoints, there are no, or very few, studies that link accumulation, chronic exposure and biological effects in natural settings. To fill the gaps, results of field studies carried out on different plant species (winter rye and wheat, spring barley, oats, Scots pine, wild vetch, crested hair-grass) in various radioecological situations (nuclear weapon testing, the Chernobyl accident, uranium and radium processing) to investigate effects of long-term chronic exposure to radionuclides are discussed. Because each impacted site developed in its own way due to a unique history of events, the experience from one case study is rarely directly applicable to another situation. In spite of high heterogeneity in response, we have detected several general patterns. Plant populations growing in areas with relatively low levels of pollution are characterized by the increased level of both cytogenetic alterations and genetic diversity. Accumulation of cellular alterations may afterward influence biological parameters important for populations such as health and reproduction. Presented data provide evidence that in plant populations inhabiting heavily contaminated territories cytogenetic damage were accompanied by decrease in reproductive ability. In less contaminated sites, because of the scarcity of data available, it is impossible to establish exactly the relationship between cytogenetic effects and reproductive ability. Radioactive contamination of the plants

  8. The effect of ongoing exposure dynamics in dose response relationships.

    Directory of Open Access Journals (Sweden)

    Josep M Pujol

    2009-06-01

    Full Text Available Characterizing infectivity as a function of pathogen dose is integral to microbial risk assessment. Dose-response experiments usually administer doses to subjects at one time. Phenomenological models of the resulting data, such as the exponential and the Beta-Poisson models, ignore dose timing and assume independent risks from each pathogen. Real world exposure to pathogens, however, is a sequence of discrete events where concurrent or prior pathogen arrival affects the capacity of immune effectors to engage and kill newly arriving pathogens. We model immune effector and pathogen interactions during the period before infection becomes established in order to capture the dynamics generating dose timing effects. Model analysis reveals an inverse relationship between the time over which exposures accumulate and the risk of infection. Data from one time dose experiments will thus overestimate per pathogen infection risks of real world exposures. For instance, fitting our model to one time dosing data reveals a risk of 0.66 from 313 Cryptosporidium parvum pathogens. When the temporal exposure window is increased 100-fold using the same parameters fitted by our model to the one time dose data, the risk of infection is reduced to 0.09. Confirmation of this risk prediction requires data from experiments administering doses with different timings. Our model demonstrates that dose timing could markedly alter the risks generated by airborne versus fomite transmitted pathogens.

  9. Tobacco Smoke Exposure during Childhood: Effect on Cochlear Physiology

    Directory of Open Access Journals (Sweden)

    Cristiane Lopes

    2013-10-01

    Full Text Available The rate of smoking in Brazil is about 18.8%. Exposure to environmental tobacco smoke is one of the major factors predisposing children to several hazardous health problems. The objective of the present research was to analyze the effect of tobacco smoke exposure during childhood on cochlear physiology by measuring the transient evoked otoacoustic emissions (TEOAE response levels. Cotinine, the main metabolite of nicotine, was measured in 145 students’ (8–10 years old urine. Sixty students indicated tobacco smoke exposure (TSE (cotinine urine levels ≥ 5.0 ng/mL and 85 did not. The evaluation of TEOAE of TSE students showed lower response levels, mainly on frequencies of 2.8 kHz on the right and left ears and 2.0 kHz on left ear and lower signal noise response levels, mainly on the 1.0 kHz and 1.4 kHz frequencies, when compared to controls that were not exposed to tobacco. The mean reduction observed in TEOAE of tobacco smoke exposure children was 2.1 dB SPL. These results have important implications on the damage to the cochlear structures and indicate a possible loss in hearing and hearing ability development.

  10. Effect of environmental exposure to Cadmium on pregnancy outcome

    Directory of Open Access Journals (Sweden)

    F. Ramezanzadeh

    2010-04-01

    Full Text Available "n "n "nBackgrounds andObjectives:The objective of the present study was to evaluate the potential effect of environmental exposure to toxic metal (cadmium on pregnancy outcome and fetal growth."nMaterials and Methods: 330 normal pregnant women were randomly selected from vali-e-asr hospital, from July 2003 through Feb. 2005. Cadmium was measured in umbilical cord blood and mother whole blood of postpartum women without occupational exposure to metals in Tehran, Iran, using inductively coupled plasma mass spectrometry"nResult: Whole blood cadmium and cord blood cadmium ranged from 0/00 to 6/30 μg/L ,respectivly. in the group higher level of maternal blood cadmium (> 0.40 μg/L 1cm decrease was seen in neonatal birth height. (p = 0.007 There was a significant association between cadmium exposure and birth weight.Mann-whitney test showed that, maternal blood cadmium level, was significantly negatively associated with neonatal birth weight (z = -1.83, P < 0.06."nConclusion: It was concluded that environmental exposure to cadmium significantly reduces neonatal birth height.

  11. The Effects of Exposure to Hyperinflation on Occupational Choice

    OpenAIRE

    Caio Waisman; João Manoel Pinho de Mello; Eduardo Zilberman

    2013-01-01

    We use data on immigrants who live in the United States to study the effects of exposure to hyperinflation on occupational choice. To do so, we calculate the number of years an individual had lived under hyperinflation before arriving to the US. We find that its marginal effect on the probability of being self-employed instead of wage-earner is 0.87 percentage point. This effect depends on the age individuals had when exposed to hyperinflation. In particular, it is stronger for individuals wh...

  12. Effects of prenatal exposure to different colors on offsprings mood

    OpenAIRE

    Afra Khosravi; Sara Faryadian

    2015-01-01

    Objective(s): There is much evidence indicating that depression is influenced by the levels of neurotransmitters such as dopamine, GABA and adrenaline. The current study we designed to investigate the effect of exposure of pregnant rats to different colors on neurotransmitters level, as indicators of mood disorders in off springs. Materials and Methods: Five groups of pregnant female Wistar rats (eight rats in each group) were enrolled in this study. Dopamine, adrenaline and GABA concentratio...

  13. Opinion on potential health effects of exposure to electromagnetic fields.

    Science.gov (United States)

    2015-09-01

    In January 2015, the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) published its final opinion on "Potential health effects of exposure to electromagnetic fields." The purpose of this document was to update previous SCENIHR opinions in the light of recently available information since then, and to give special consideration to areas that had not been dealt with in the previous opinions or in which important knowledge gaps had been identified.

  14. The effect of prenatal natural disaster exposure on school outcomes.

    Science.gov (United States)

    Fuller, Sarah C

    2014-08-01

    This study looks at the impact of exposure to natural disasters during pregnancy on the educational outcomes of North Carolina children at the third grade level. A broad literature relates negative birth outcomes to poor educational performance, and a number of recent studies have examined the effect of prenatal exposure to natural disasters on birth outcomes. This study takes the next step by considering how prenatal exposure affects later outcomes. Combining North Carolina administrative data on births and school performance with disaster declarations from the U.S. Federal Emergency Management Agency (FEMA) allows for the identification of children who were exposed to disasters during prenatal development. These children are compared with other children born in the same county who were not exposed to disasters while in utero. Regression results suggest that children exposed to hurricanes prenatally have lower scores on third grade standardized tests in math and reading. Those exposed to flooding or tornadoes also have somewhat lower math scores. Additionally, results suggest that these negative effects are more concentrated among children in disadvantaged subgroups, especially children born to black mothers. However, no evidence exists that these effects are mediated by common measures of birth outcomes, including birth weight and gestational age.

  15. The mere exposure effect in the domain of haptics.

    Directory of Open Access Journals (Sweden)

    Martina Jakesch

    Full Text Available BACKGROUND: Zajonc showed that the attitude towards stimuli that one had been previously exposed to is more positive than towards novel stimuli. This mere exposure effect (MEE has been tested extensively using various visual stimuli. Research on the MEE is sparse, however, for other sensory modalities. METHODOLOGY/PRINCIPAL FINDINGS: We used objects of two material categories (stone and wood and two complexity levels (simple and complex to test the influence of exposure frequency (F0 = novel stimuli, F2 = stimuli exposed twice, F10 = stimuli exposed ten times under two sensory modalities (haptics only and haptics & vision. Effects of exposure frequency were found for high complex stimuli with significantly increasing liking from F0 to F2 and F10, but only for the stone category. Analysis of "Need for Touch" data showed the MEE in participants with high need for touch, which suggests different sensitivity or saturation levels of MEE. CONCLUSIONS/SIGNIFICANCE: This different sensitivity or saturation levels might also reflect the effects of expertise on the haptic evaluation of objects. It seems that haptic and cross-modal MEEs are influenced by factors similar to those in the visual domain indicating a common cognitive basis.

  16. Anxiogenic-like effects of chronic nicotine exposure in zebrafish.

    Science.gov (United States)

    Stewart, Adam Michael; Grossman, Leah; Collier, Adam D; Echevarria, David J; Kalueff, Allan V

    2015-12-01

    Nicotine is one of the most widely used and abused legal drugs. Although its pharmacological profile has been extensively investigated in humans and rodents, nicotine CNS action remains poorly understood. The importance of finding evolutionarily conserved signaling pathways, and the need to apply high-throughput in vivo screens for CNS drug discovery, necessitate novel efficient experimental models for nicotine research. Zebrafish (Danio rerio) are rapidly emerging as an excellent organism for studying drug abuse, neuropharmacology and toxicology and have recently been applied to testing nicotine. Anxiolytic, rewarding and memory-modulating effects of acute nicotine treatment in zebrafish are consistently reported in the literature. However, while nicotine abuse is more relevant to long-term exposure models, little is known about chronic effects of nicotine on zebrafish behavior. In the present study, chronic 4-day exposure to 1-2mg/L nicotine mildly increased adult zebrafish shoaling but did not alter baseline cortisol levels. We also found that chronic exposure to nicotine evokes robust anxiogenic behavioral responses in zebrafish tested in the novel tank test paradigm. Generally paralleling clinical and rodent data on anxiogenic effects of chronic nicotine, our study supports the developing utility of zebrafish for nicotine research. PMID:25643654

  17. 极低频磁场联合或不联合X射线对CHO细胞动粒阳性和阴性微核生成的影响%Effects of ELF magnetic fields exposure with or without X-rays on induction of kinetochore positive and negative micronuclei in CHO cells

    Institute of Scientific and Technical Information of China (English)

    DING Guirong; GUO Guozhen

    2005-01-01

    Extremely low frequency magnetic field (ELFMF) produced by power lines and household electric appliances has been associated with increased incidence of cancers, as was suggested by several epidemiological studies[1]. To test the genotoxic effects of ELFMF, the induction of micronuclei by exposure to ELFMF and/or X-rays was investigated by cytokinesis-block method in cultured Chinese Hamster Ovary (CHO) cells. Approximately 4×105 cells were plated in 10cm dishes, following exposure to an ELF magnetic field (60Hz, 5 mT) for 24h. The cells were irradiated to 1 Gy by X-rays. After the irradiation, cytochalasin B was added to the medium at a final concentration of 3 μg / mL. The cells were then exposed to an ELF magnetic field or placed in a normal incubator for 18 h, which is 1.5 times the length of their cell cycle. The micronuclei derived from acentric fragments or from whole chromosomes were evaluated with the help of immunofluorescent staining using antikinetochore antibodies from the serum of scleroderma (CREST syndrome) patients[2,3].Statistically, no significant difference in the frequency of binucleated cells carrying micronuclei was observed between CHO cells cultured in the normal incubator and those placed in the exposure system for 24h. Following X-ray irradiation, the number of binucleated cells carrying micronuclei increased significantly (p< 0.01). Exposure to an ELF magnetic field for 24 h before the X-ray irradiation or for 18 h after X-ray-irradiation did not affect the number of X-ray-induced micronuclei. Among the micronuclei induced by X-ray-irradiation, only a small number were kinetochore-positive (approximately 4 %). The number of kinetochore-positive micronuclei was significantly increased in the cells treated with X-ray irradiation followed by ELFMF exposure or M+X+M treated cells (exposure to ELF magnetic field before and after X-ray irradiation), but not in the cells treated with ELFMF exposure before X-ray irradiation compared with

  18. Effects of Exposure to Advertisements on Audience Impressions

    Science.gov (United States)

    Hasegawa, Hiroshi; Sato, Mie; Kasuga, Masao; Nagao, Yoshihide; Shono, Toru; Norose, Yuka; Oku, Ritsuya; Nogami, Akira; Miyazawa, Yoshitaka

    This study investigated effects of listening and/or watching commercial-messages (CMs) on audience impressions. We carried out experiments of TV advertisements presentation in conditions of audio only, video only, and audio-video. As results, we confirmed the following two effects: image-multiple effect, that is, the audience brings to mind various images that are not directly expressed in the content, and marking-up effect, that is, the audience concentrates on some images that are directly expressed in the content. The image-multiple effect, in particular, strongly appeared under the audio only condition. Next, we investigated changes in the following seven subjective responses; usage image, experience, familiarity, exclusiveness, feeling at home, affection, and willingness to buy, after exposure to advertisements under conditions of audio only and audio-video. As a result, noting that the image-multiple effect became stronger as the evaluation scores of the responses increased.

  19. Radiation-induced stress effects following low dose exposure

    International Nuclear Information System (INIS)

    Complete text of publication follows. Recent advances in our understanding of effects of radiation on living cells suggest that fundamentally different mechanisms are operating at low doses compared with high doses. Also, acute low doses appear to involve different response mechanisms compared with chronic low doses. Both genomic instability and so called 'bystander effects' show many similarities with well known cellular responses to oxidative stress. These predominate following low dose exposures and are maximally expressed at doses as low as 5mGy. At the biological level this is not surprising. Chemical toxicity has been known for many years to show these patterns of dose response. Cell signaling and coordinated stress mechanisms appear to dominate acute low dose exposure to chemicals. Adaptation to chemical exposures is also well documented although mechanisms of adaptive responses are less clear. In the radiation field adaptive responses also become important when low doses are protracted or fractionated. Recent data from our group concerning bystander effects following multiple low dose exposures suggest that adaptive responses can be induced in cells which only receive signals from irradiated neighbours. We have data showing delayed and bystander effects in humans, rodents 3 fish species and in prawns following in vitro and/or in vivo irradiation of haematopoietic tissues and, from the aquatic groups, gill and skin/fin tissue. Bystander signals induced by radiation can be communicated from fish to fish in vivo and are detectable as early as the eyed egg stage, i.e. as soon as tissue starts to develop. Using proteomic approaches we have determined that the bystander and the direct irradiation proteomes are different. The former show significant upregulation of 5 proteins with anti-oxidant, regenerative and restorative functions while the direct radiation proteome has 2 upregulated proteins both involved in proliferation. These data have implications for

  20. Delayed effects of external radiation exposure: a brief history.

    Science.gov (United States)

    Miller, R W

    1995-11-01

    Within months of Roentgen's discovery of X rays, severe adverse effects were reported, but not well publicized. As a result, over the next two decades, fluoroscope operators suffered lethal skin carcinomas. Later, case reports appeared concerning leukemia in radiation workers, and infants born with severe mental retardation after their mothers had been given pelvic radiotherapy early in pregnancy. Fluoroscopy and radiotherapy for benign disorders continued to be used with abandon until authoritative reports were published on the adverse effects of ionizing radiation by the U.S. NAS-NRC and the UK MRC in 1956. Meanwhile, exposure to the atomic bombs in Japan had occurred and epidemics of delayed effects began to be recognized among the survivors: cataracts (1949), leukemia (1952) and severe mental retardation among newborn infants after intrauterine exposure (1952). No statistically significant excess of germ-cell genetic effects was detected by six clinical measurements (1956), the F1 mortality (1981), cytogenetic studies (1987) or biochemical genetic studies (1988). Somatic cell effects were revealed by long-lasting chromosomal aberrations in peripheral lymphocytes (1968), and somatic cell mutations were found at the glycophorin A locus in erythrocytes (1992). Molecular biology is a likely focus of new studies based on the function of the gene for ataxia telangiectasia (1995), a disorder in which children have severe, even lethal acute radiation reactions when given conventional doses of radiotherapy for lymphoma, to which they are prone. Also, obligate heterozygote female relatives can be studied for increased susceptibility to radiation-induced breast cancer, as suggested by clinical studies. The tumor registries in Hiroshima and Nagasaki now provide incidence data that show the extent of increases in eight common cancers and no increase in eight others (1994). The possibility of very late effects of A-bomb exposure is suggested by recent reports of increased

  1. Delayed effects of external radiation exposure: A brief history

    International Nuclear Information System (INIS)

    Within months of Roentgen's discovery of X rays, severe adverse effects were reported, but not well publicized. As a result, over the next two decades, fluoroscope operators suffered lethal skin carcinomas. Later, case reports appeared concerning leukemia in radiation workers, and infants born with severe mental retardation after their mothers had been given pelvic radiotherapy early in pregnancy. Fluoroscopy and radiotherapy for benign disorders continued to be used with abandon until authoritative reports were published on the adverse effects of ionizing radiation by the U.S. NAS-NRC and the UK MRC in 1956. Meanwhile, exposure to the atomic bombs in Japan had occurred and epidemics of delayed effects began to be recognized among the survivors: cataracts, leukemia and severe mental retardation among newborn infants after intra-uterine exposure. No statistically significant excess of germ-cell genetic effects was detected by six clinical measurements, the F1 mortality, cytogenetic studies or biochemical genetic studies. Somatic cell effects were revealed by long-lasting chromosomal aberrations in peripheral lymphocytes, and somatic cell mutations were found at the glycophorin A locus in erythrocytes. Molecular biology is a likely focus of new studies based on the function of the gene for ataxia telangiectasia, a disorder in which children have severe, even lethal acute radiation reactions when given conventional doses of radiotherapy for lymphoma, to which they are prone. The tumor registries in Hiroshima and Nagasaki now provide incidence data that show the extent of increases in eight common cancers and no increase in eight others. The possibility of very late effects of A-bomb exposure is suggested by recent reports of increased frequencies of hyperparathyroidism, parathyroid cancers and certain causes of death other than cancer. 88 refs., 1 fig

  2. [Health effects of occupational exposure among shoe workers. A review].

    Science.gov (United States)

    Szadkowska-Stańczyk, Irena; Woźniak, Helena; Stroszejn-Mrowca, Grazyna

    2003-01-01

    World-wide epidemiological studies provide evidence that the employment in the shoe production and repair plants is associated with an enhanced risk for cancer (primarily nose and nasal sinuses). According to the majority of authors, it is induced by exposure to leather dust. It is also known that, leather dust particles contain numerous chemicals acquired during the process of leather tanning and finishing (chromium salts, vegetable dye extracts, mineral oils). Some of these compounds exert carcinogenic effect. This paper provides a review of the results of epidemiological studies on health effects of exposure to harmful factors present mainly at the footwear production and repair. These results reveal an enhanced risk for cancer of nose or nasal sinuses induced by leather dust, as well as neoplasms of hematopoietic and lymphatic systems, resulting from exposure to solvents (mostly benzene). Among non-neoplasms, diseases of the musculoskeletal system associated with ergonomic factors, contact dermatics, chronic pulmonary diseases and damage of peripheral nerves in solvent-exposed workers are diagnosed. PMID:12731407

  3. Health effects assessment of exposure to particles from wood smoke

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Elsa; Dybdahl, M. (Technical Univ. of Denmark, National Food Institute, Dept. of Toxicology and Risk Assessment, Soeborg (Denmark)); Larsen, Poul Bo (Danish Environmental Protection Agency, Copenhagen (Denmark))

    2008-07-01

    The number of residential wood burning devices has increased in Denmark during the latest years and it has been estimated that there in 2005 were about 551,000 wood stoves and about 48,000 wood boilers in Denmark. This has resulted in an increased exposure of the general Danish population to pollutants associated with residential wood smoke. New Danish monitoring results on particulate matter (PM) in ambient air have shown elevated PM levels in areas with many wood stoves, particularly during wintertime when wood burning is common. Due to the size distribution of wood smoke particles essentially all will be contained in the PM{sub 2.5} fraction. It has been estimated that about 17,665 tonnes PM{sub 2.5} per year (2005) in Denmark come from residential wood combustion. Therefore, there is an increasing concern that adverse human health effects might be associated with the increased exposure to residential wood smoke. This project has been set up in order to review the scientific literature concerning adverse health effects of pollutants associated with residential wood smoke with the main focus on particulate matter and to quantify and evaluate, if possible, the impact on human health of the increased exposure to particles in residential wood smoke. (au)

  4. Developmental and behavioral effects of postnatal amitraz exposure in rats

    Directory of Open Access Journals (Sweden)

    J. Palermo-Neto

    1997-08-01

    Full Text Available The effects of postnatal amitraz exposure on physical and behavioral parameters were studied in Wistar rats, whose lactating dams received the pesticide (10 mg/kg orally on days 1, 4, 7, 10, 13, 16 and 19 of lactation; control dams received distilled water (1 ml/kg on the same days. A total of 18 different litters (9 of them control and 9 experimental born after a 21-day gestation were used. The results showed that the median effective time (ET50 for fur development, eye opening, testis descent and onset of the startle response were increased in rats postnatally exposed to amitraz (2.7, 15.1, 21.6 and 15.3 days, respectively compared to those of the control pups (1.8, 14.0, 19.9 and 12.9 days, respectively. The ages of incisor eruption, total unfolding of the external ears, vaginal and ear opening and the time taken to perform the grasping hindlimb reflex were not affected by amitraz exposure. Pups from dams treated with amitraz during lactation took more time (in seconds to perform the surface righting reflex on postnatal days (PND 3 (25.0 ± 2.0, 4 (12.3 ± 1.2 and 5 (8.7 ± 0.9 in relation to controls (10.6 ± 1.2; 4.5 ± 0.6 and 3.4 ± 0.4, respectively; the climbing response was not changed by amitraz. Postnatal amitraz exposure increased spontaneous motor activity of male and female pups in the open-field on PND 16 (140 ± 11 and 17 (124 ± 12, and 16 (104 ± 9, 17 (137 ± 9 and 18 (106 ± 8, respectively. Data on spontaneous motor activity of the control male and female pups were 59 ± 11 and 69 ± 10 for days 16 and 17 and 49 ± 9, 48 ± 7 and 56 ± 7 for days 16, 17 and 18, respectively. Some qualitative differences were also observed in spontaneous motor behavior; thus, raising the head, shoulder and pelvis matured one or two days later in the amitraz-treated offspring. Postnatal amitraz exposure did not change locomotion and rearing frequencies or immobility time in the open-field on PND 30, 60 and 90. The present findings indicate

  5. The effects of acute radiation exposure on the serum components

    International Nuclear Information System (INIS)

    The blood samples were collected from the experimental animals 24 hrs after irradiation of gamma doses upto 80 Gy. Native PAGE showed a decreasing trend in gamma globulin fraction of serum from the irradiated group compared to control, while SDS PAGE indicated an enhanced tendency in protein of molecular weight 30,000 to 40,000. Serum albumin slightly decreased with radiation doses as a result of decrease in total protein amount. Radiation exposure had little or no effects on such lipid related components as phospholipid, triglyceride, and cholesterol, respectively. Among others, glutamic pyryvic transaminase (GPT) showed a drastic decrease in its amount 24 hrs after radiation exposure, which can be applied to the health care program for radiation workers. (Author)

  6. Mold exposure and health effects following hurricanes Katrina and Rita.

    Science.gov (United States)

    Barbeau, Deborah N; Grimsley, L Faye; White, LuAnn E; El-Dahr, Jane M; Lichtveld, Maureen

    2010-01-01

    The extensive flooding in the aftermath of Hurricanes Katrina and Rita created conditions ideal for indoor mold growth, raising concerns about the possible adverse health effects associated with indoor mold exposure. Studies evaluating the levels of indoor and outdoor molds in the months following the hurricanes found high levels of mold growth. Homes with greater flood damage, especially those with >3 feet of indoor flooding, demonstrated higher levels of mold growth compared with homes with little or no flooding. Water intrusion due to roof damage was also associated with mold growth. However, no increase in the occurrence of adverse health outcomes has been observed in published reports to date. This article considers reasons why studies of mold exposure after the hurricane do not show a greater health impact. PMID:20070193

  7. Biological effects of static and low-frequency electromagnetic fields: an overview of United States literature

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, R.D.; Kaune, W.T.

    1977-04-12

    Results are reviewed from a number of studies on the biological effects of static and low frequency electromagnetic fields on animals. Based on a long history of experience with electric fields by the utility industry, it appears that intermittent and repeated exposures to strong 60-Hz electromagnetic fields from present power transmission systems have no obvious adverse effect on the health of man. It has been recognized recently that this belief must be tested by carefully designed and executed experiments under laboratory conditions where precise control can be exercised over coexisting environmental factors. A number of studies have been initiated in response to this need to evaluate possible effects from both acute and chronic exposures. 100 references.

  8. Effective post-exposure treatment of Ebola infection.

    Directory of Open Access Journals (Sweden)

    Heinz Feldmann

    2007-01-01

    Full Text Available Ebola viruses are highly lethal human pathogens that have received considerable attention in recent years due to an increasing re-emergence in Central Africa and a potential for use as a biological weapon. There is no vaccine or treatment licensed for human use. In the past, however, important advances have been made in developing preventive vaccines that are protective in animal models. In this regard, we showed that a single injection of a live-attenuated recombinant vesicular stomatitis virus vector expressing the Ebola virus glycoprotein completely protected rodents and nonhuman primates from lethal Ebola challenge. In contrast, progress in developing therapeutic interventions against Ebola virus infections has been much slower and there is clearly an urgent need to develop effective post-exposure strategies to respond to future outbreaks and acts of bioterrorism, as well as to treat laboratory exposures. Here we tested the efficacy of the vesicular stomatitis virus-based Ebola vaccine vector in post-exposure treatment in three relevant animal models. In the guinea pig and mouse models it was possible to protect 50% and 100% of the animals, respectively, following treatment as late as 24 h after lethal challenge. More important, four out of eight rhesus macaques were protected if treated 20 to 30 min following an otherwise uniformly lethal infection. Currently, this approach provides the most effective post-exposure treatment strategy for Ebola infections and is particularly suited for use in accidentally exposed individuals and in the control of secondary transmission during naturally occurring outbreaks or deliberate release.

  9. Dust Exposure and Respiratory Health Effects in Cement Production

    Directory of Open Access Journals (Sweden)

    Golamreza Pouryaghoub

    2012-02-01

    Full Text Available Dust can be produced by almost all production processes in Portland cement factory. Dust exposure potentially can affect respiratory function. But evidence for respiratory effect of cement dust exposure has not been conclusive. In this study we assessed effect of cement dust exposure on respiratory function in a cement production factory. A respiratory symptoms questionnaire was completed and pulmonary function tests were carried out on 94 exposed and 54 non exposed workers at a cement factory in the east of Iran. Additionally, respirable dust level was determined by the gravimetric method. X-ray fluorescence (XRF technique was performed to determine the silica phases and the SiO2 contents of the bulk samples. The arithmetic means (AM of personal respirable dust were 30.18 mg/m3 in the crushing, 27 mg/m3 in the packing, 5.4 mg/m3 in the cement mill, 5.9 mg/m3 in the kiln and 5.48 mg/m3 in the maintenance that were higher than threshold limit value (TLV of the American Conference of Governmental Industrial Hygienists (ACGIH which is 5 mg/m3. This value in the unexposed group was 0.93 mg/m3. In this study cough, sputum, wheezing and dyspnea were more prevalent among exposed subjects. Exposed workers compared to the unexposed group showed significant reduction in Forced Expiratory Volume in one second (FEV1, Forced Vital Capacity (FVC, and Forced Expiratory Flow between 25% and 75% of the FVC (FEF25-75% (P<0.05. It can be concluded that in our study there was close and direct association between cement dust exposure and functional impairment among the cement factory workers.

  10. TransRapid TR-07 maglev-spectrum magnetic field effects on daily pineal indoleamine metabolic rhythms in rodents

    Energy Technology Data Exchange (ETDEWEB)

    Groh, K.R.

    1993-06-01

    This study examined the effects on pineal function of magnetic field (MF) exposures (ac and dc components) similar to those produced by the TransRapid TR-07 and other electromagnetic maglev systems (EMS). Rats were entrained to a light-dark cycle and then exposed to a continuous, or to an inverted, intermittent (on = 45 s, off = 15 s, induced current = 267 G/s) simulated multifrequency ac and dc magnetic field (MF) at 1 or 7 times the TR-07 maglev vehicle MF intensity for 2 hr. Other groups of rats were exposed to only the ac or the dc-component of the maglev MF. For comparison, one group was exposed to an inverted, intermittent 60-Hz MF. Each group was compared to an unexposed group of rats for changes in pineal melatonin and serotonin-N-acetyltransferase (NAT). MF exposures at an intensity equivalent to that produced by the TR-07 vehicle had no effect on melatonin or NAT compared with sham-exposed animals under any of the conditions examined. However, 7X TR-07-level continuous 2-h MF exposures significantly depressed pineal NAT by 45%. Pineal melatonin was also depressed 33--43% by a continuous 7X TR-07 MF exposure and 28% by an intermittent 60-Hz 850-mG MF, but the results were not statically significant. This study demonstrates that intermittent, combined ac and dc MFs similar to those produced by the TR-07 EMS maglev vehicle alter the normal circadian rhythm of pineal indoleamine metabolism. The pineal regulatory enzyme NAT was more sensitive to MF exposure than melatonin and may be a more desirable measure of the biological effects of MF exposure.

  11. TransRapid TR-07 maglev-spectrum magnetic field effects on daily pineal indoleamine metabolic rhythms in rodents

    Energy Technology Data Exchange (ETDEWEB)

    Groh, K.R.

    1993-01-01

    This study examined the effects on pineal function of magnetic field (MF) exposures (ac and dc components) similar to those produced by the TransRapid TR-07 and other electromagnetic maglev systems (EMS). Rats were entrained to a light-dark cycle and then exposed to a continuous, or to an inverted, intermittent (on = 45 s, off = 15 s, induced current = 267 G/s) simulated multifrequency ac and dc magnetic field (MF) at 1 or 7 times the TR-07 maglev vehicle MF intensity for 2 hr. Other groups of rats were exposed to only the ac or the dc-component of the maglev MF. For comparison, one group was exposed to an inverted, intermittent 60-Hz MF. Each group was compared to an unexposed group of rats for changes in pineal melatonin and serotonin-N-acetyltransferase (NAT). MF exposures at an intensity equivalent to that produced by the TR-07 vehicle had no effect on melatonin or NAT compared with sham-exposed animals under any of the conditions examined. However, 7X TR-07-level continuous 2-h MF exposures significantly depressed pineal NAT by 45%. Pineal melatonin was also depressed 33--43% by a continuous 7X TR-07 MF exposure and 28% by an intermittent 60-Hz 850-mG MF, but the results were not statically significant. This study demonstrates that intermittent, combined ac and dc MFs similar to those produced by the TR-07 EMS maglev vehicle alter the normal circadian rhythm of pineal indoleamine metabolism. The pineal regulatory enzyme NAT was more sensitive to MF exposure than melatonin and may be a more desirable measure of the biological effects of MF exposure.

  12. Molecular effects of diethanolamine exposure on Calanus finmarchicus (Crustacea: Copepoda)

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Bjorn Henrik, E-mail: bjorn.h.hansen@sintef.no [SINTEF Materials and Chemistry, Marine Environmental Technology, Brattorkaia 17B, N-7465 Trondheim (Norway); Altin, Dag [BioTrix, N-7022 Trondheim (Norway); Booth, Andy; Vang, Siv-Hege; Frenzel, Max; Sorheim, Kristin Rist; Brakstad, Odd Gunnar [SINTEF Materials and Chemistry, Marine Environmental Technology, Brattorkaia 17B, N-7465 Trondheim (Norway); Storseth, Trond R. [SINTEF Fisheries and Aquaculture, N-7465 Trondheim (Norway)

    2010-08-15

    Alkanolamines are surface-active chemicals used in a wide range of industrial, agricultural and pharmaceutical applications and products. Of particular interest is the use of alkanolamines such as diethanolamine (DEA) in the removal of CO{sub 2} from natural gas and for CO{sub 2} capture following fossil fuel combustion. Despite this widespread use, relatively little is known about the ecotoxicological impacts of these compounds. In an attempt to assess the potential effects of alkanolamines in the marine environment, a key species in the North Atlantic, the planktonic copepod Calanus finmarchicus, was studied for molecular effects following sublethal exposure to DEA. DEA-induced alterations in transcriptome and metabolome profiling were assessed using a suppression subtractive hybridization (SSH) gene library method and high resolution magic angle spinning nuclear magnetic resonance (HR-MAS NMR), respectively. Effects were observed on transcription of genes reportedly involved in lipid metabolism, antioxidant systems, metal binding, and amino acid and protein catabolism. These effects were accompanied by altered expression of fatty acid derivates, amino acids (threonine, methionine, glutamine, arginine, alanine and leucine) and cholines (choline, phosphocholine and glycerophosphocholine). Together, SSH and HR-MAS NMR offer complementary screening tools for the assessment of molecular responses of C. finmarchicus to DEA and can be used in the study of other chemicals and organisms. Concentration-response and time-response relationships between DEA exposure and single gene transcription were investigated using quantitative PCR. Specific relationships were found between DEA exposure and the transcription of genes involved in protein catabolism (ubiquitin-specific protease-7), metal ion homeostasis (ferritin) and defence against oxidative stress ({gamma}-glutamylcysteine synthase, glutathione synthase and Cu/Zn-superoxide dismutase). At the lowest alkanolamine

  13. Health effect from EMF exposure of Korea population

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y. S.; Cho, Y. S.; Lee, J. T.; Yup, M. J.; Hong, J. H. [Institute of Environmental and Industrrial Medicine, Hanyang Univ., Seoul (Korea, Republic of)

    2002-07-01

    This study on health effect from EMF exposure was performed from June 2001 to April 2002 to compare changes in melatonin levels in urine of 40 subjects during their normal sleeping hours, to evaluate heart rate, ST segment in ventricular, and ventricular premature beat for cardiac function, to evaluate microwave exposure from cellular phones which may have a potential influence on the electro physiologic function of human brain, and each 20 subjects in occupational and non-occupational group measured personal 24-h continual exposure, using EMDEX(for 40-800Hz, Enertech Consultant, Inc.). An urine samples for analysis of melatonin excretion level were collected 1 times a day(immediately after wake-up) for five days from each subjects and analyzed by radioimmunoassay, HRV-test for relationship between heart rate and EMF exposure was performed heart rate beat using Holter for subjects, and double EEG-test were performed in 10 long-term users of the cellularphones when using and not using them, and a single EEG-test in 10 short-term users of the cellular phones. Each EEG-recording took 40 min consisting of 30 min filed exposure and 10 min measurement. And We estimated the economic value of the potential damage of electromagnetic radiation from cellular phone, and the willingness to pay of people for the study of the radiation damage led by the government, by applying contingent variation method. The results of this study were followed; 1. Personal exposure assessment 2. We showed not significant difference for the subjective average melatonin levels between occupational and non- occupational groups exposed to electromagnetic fields. 3. We showed no difference in the awake EEGs in terms of spectral power density measures between long-term users and short-term users of cellular phones. 4. We found that the economic value of the potential damage by the radiation for a typical cellular phone user is about 20,000 won per year and he would be willing to pay about 1,800 won

  14. Radon exposure of the skin: I. Biological effects

    International Nuclear Information System (INIS)

    Radon progeny can plate out on skin and give rise to exposure of the superficial epidermis from alpha emitters Po-218 (7.7 MeV, range ∼66 μm) and Po-214 (6 MeV, range ∼44 μm). Dose rates from beta/gamma emitters Pb-214 and Bi-214 are low and only predominate at depths in excess of the alpha range. This paper reviews the evidence for a causal link between exposure from radon and its progeny, and deterministic and stochastic biological effects in human skin. Radiation induced skin effects such as ulceration and dermal atrophy, which require irradiation of the dermis, are ruled out for alpha irradiation from radon progeny because the target cells are considerably deeper than the range of alpha particles. They have not been observed in man or animals. Effects such as erythema and acute epidermal necrosis have been observed in a few cases of very high dose alpha particle exposures in man and after acute high dose exposure in animals from low energy beta radiations with similar depth doses to radon progeny. The required skin surface absorbed doses are in excess of 100 Gy. Such effects would require extremely high levels of radon progeny. They would involve quite exceptional circumstances, way outside the normal range of radon exposures in man. There is no definitive identification of the target cells for skin cancer induction in animals or man. The stem cells in the basal layer which maintain the epidermis are the most plausible contenders for target cells. The majority of these cells are near the end of the range of radon progeny alpha particles, even on the thinnest body sites. The nominal depth of these cells, as recommended by the International Commission on Radiological Protection (ICRP), is 70 μm. There is evidence however that some irradiation of the hair follicles and/or the deeper dermis, as well as the inter-follicular epidermis, is also necessary for skin cancer induction. Alpha irradiation of rodent skin that is restricted to the epidermis does not

  15. Radon exposure of the skin: I. Biological effects

    Energy Technology Data Exchange (ETDEWEB)

    Charles, M W [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2007-09-15

    Radon progeny can plate out on skin and give rise to exposure of the superficial epidermis from alpha emitters Po-218 (7.7 MeV, range {approx}66 {mu}m) and Po-214 (6 MeV, range {approx}44 {mu}m). Dose rates from beta/gamma emitters Pb-214 and Bi-214 are low and only predominate at depths in excess of the alpha range. This paper reviews the evidence for a causal link between exposure from radon and its progeny, and deterministic and stochastic biological effects in human skin. Radiation induced skin effects such as ulceration and dermal atrophy, which require irradiation of the dermis, are ruled out for alpha irradiation from radon progeny because the target cells are considerably deeper than the range of alpha particles. They have not been observed in man or animals. Effects such as erythema and acute epidermal necrosis have been observed in a few cases of very high dose alpha particle exposures in man and after acute high dose exposure in animals from low energy beta radiations with similar depth doses to radon progeny. The required skin surface absorbed doses are in excess of 100 Gy. Such effects would require extremely high levels of radon progeny. They would involve quite exceptional circumstances, way outside the normal range of radon exposures in man. There is no definitive identification of the target cells for skin cancer induction in animals or man. The stem cells in the basal layer which maintain the epidermis are the most plausible contenders for target cells. The majority of these cells are near the end of the range of radon progeny alpha particles, even on the thinnest body sites. The nominal depth of these cells, as recommended by the International Commission on Radiological Protection (ICRP), is 70 {mu}m. There is evidence however that some irradiation of the hair follicles and/or the deeper dermis, as well as the inter-follicular epidermis, is also necessary for skin cancer induction. Alpha irradiation of rodent skin that is restricted to the

  16. An empirical assessment of exposure measurement errors and effect attenuation in bi-pollutant epidemiologic models

    Science.gov (United States)

    Using multipollutant models to understand the combined health effects of exposure to multiple pollutants is becoming more common. However, the complex relationships between pollutants and differing degrees of exposure error across pollutants can make health effect estimates from ...

  17. Arsenic exposure induces the Warburg effect in cultured human cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Fei; Severson, Paul; Pacheco, Samantha; Futscher, Bernard W.; Klimecki, Walter T., E-mail: klimecki@pharmacy.arizona.edu

    2013-08-15

    Understanding how arsenic exacts its diverse, global disease burden is hampered by a limited understanding of the particular biological pathways that are disrupted by arsenic and underlie pathogenesis. A reductionist view would predict that a small number of basic pathways are generally perturbed by arsenic, and manifest as diverse diseases. Following an initial observation that arsenite-exposed cells in culture acidify their media more rapidly than control cells, the report here shows that low level exposure to arsenite (75 ppb) is sufficient to induce aerobic glycolysis (the Warburg effect) as a generalized phenomenon in cultured human primary cells and cell lines. Expanded studies in one such cell line, the non-malignant pulmonary epithelial line, BEAS-2B, established that the arsenite-induced Warburg effect was associated with increased accumulation of intracellular and extracellular lactate, an increased rate of extracellular acidification, and inhibition by the non-metabolized glucose analog, 2-deoxy-D-glucose. Associated with the induction of aerobic glycolysis was a pathway-wide induction of glycolysis gene expression, as well as protein accumulation of an established glycolysis master-regulator, hypoxia-inducible factor 1A. Arsenite-induced alteration of energy production in human cells represents the type of fundamental perturbation that could extend to many tissue targets and diseases. - Highlights: • Chronic arsenite exposure induces aerobic glycolysis, dubbed the “Warburg effect”. • Arsenite-induced Warburg effect is a general phenomenon in cultured human cells. • HIF-1A may mediate arsenite induced Warburg effect.

  18. Arsenic exposure induces the Warburg effect in cultured human cells

    International Nuclear Information System (INIS)

    Understanding how arsenic exacts its diverse, global disease burden is hampered by a limited understanding of the particular biological pathways that are disrupted by arsenic and underlie pathogenesis. A reductionist view would predict that a small number of basic pathways are generally perturbed by arsenic, and manifest as diverse diseases. Following an initial observation that arsenite-exposed cells in culture acidify their media more rapidly than control cells, the report here shows that low level exposure to arsenite (75 ppb) is sufficient to induce aerobic glycolysis (the Warburg effect) as a generalized phenomenon in cultured human primary cells and cell lines. Expanded studies in one such cell line, the non-malignant pulmonary epithelial line, BEAS-2B, established that the arsenite-induced Warburg effect was associated with increased accumulation of intracellular and extracellular lactate, an increased rate of extracellular acidification, and inhibition by the non-metabolized glucose analog, 2-deoxy-D-glucose. Associated with the induction of aerobic glycolysis was a pathway-wide induction of glycolysis gene expression, as well as protein accumulation of an established glycolysis master-regulator, hypoxia-inducible factor 1A. Arsenite-induced alteration of energy production in human cells represents the type of fundamental perturbation that could extend to many tissue targets and diseases. - Highlights: • Chronic arsenite exposure induces aerobic glycolysis, dubbed the “Warburg effect”. • Arsenite-induced Warburg effect is a general phenomenon in cultured human cells. • HIF-1A may mediate arsenite induced Warburg effect

  19. Effects of light exposure on the TL dating of pottery

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Bleaching experiments on Chinese pottery fine grains were conducted under sunlight and laboratory light conditions. It is found that the thermoluminescence (TL) at high temperatures can be bleached significantly, but no effects were observed on TL signals used for the pre-dose dating technique. It is concluded that the pre-dose dating technique can be applied to samples even after light exposures. Pottery samples of Tang Dynasty and New Stone Age were studied. Modifications to routine pre-dose dating technique are proposed with adding preheat procedures and using saturation exponential fitting for the sensitivity change data. The modified technique can extend the dating range to New Stone Age.

  20. Exposure effects on the optical properties of building materials

    Science.gov (United States)

    Lane, Sarah; Cathcart, J. Michael; Harrell, J. Timothy

    2008-04-01

    Georgia Tech recently initiated a weathering effects measurement program to monitor the optical properties of several common building materials. A set of common building materials were placed outdoors and optical property measurements made over a series of weeks to assess the impact of exposure on these properties. Both reflectivity and emissivity measurements were made. Materials in this program included aluminum flashing, plastic sheets, bricks, roof shingles, and tarps. This paper will discuss the measurement approach, experimental setup, and present preliminary results from the optical property measurements.

  1. Predictive modeling of nanomaterial exposure effects in biological systems

    Directory of Open Access Journals (Sweden)

    Liu X

    2013-09-01

    Full Text Available Xiong Liu,1 Kaizhi Tang,1 Stacey Harper,2 Bryan Harper,2 Jeffery A Steevens,3 Roger Xu1 1Intelligent Automation, Inc., Rockville, MD, USA; 2Department of Environmental and Molecular Toxicology, School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, OR, USA; 3ERDC Environmental Laboratory, Vicksburg, MS, USA Background: Predictive modeling of the biological effects of nanomaterials is critical for industry and policymakers to assess the potential hazards resulting from the application of engineered nanomaterials. Methods: We generated an experimental dataset on the toxic effects experienced by embryonic zebrafish due to exposure to nanomaterials. Several nanomaterials were studied, such as metal nanoparticles, dendrimer, metal oxide, and polymeric materials. The embryonic zebrafish metric (EZ Metric was used as a screening-level measurement representative of adverse effects. Using the dataset, we developed a data mining approach to model the toxic endpoints and the overall biological impact of nanomaterials. Data mining techniques, such as numerical prediction, can assist analysts in developing risk assessment models for nanomaterials. Results: We found several important attributes that contribute to the 24 hours post-fertilization (hpf mortality, such as dosage concentration, shell composition, and surface charge. These findings concur with previous studies on nanomaterial toxicity using embryonic zebrafish. We conducted case studies on modeling the overall effect/impact of nanomaterials and the specific toxic endpoints such as mortality, delayed development, and morphological malformations. The results show that we can achieve high prediction accuracy for certain biological effects, such as 24 hpf mortality, 120 hpf mortality, and 120 hpf heart malformation. The results also show that the weighting scheme for individual biological effects has a significant influence on modeling the overall impact of

  2. Effects of hemin and thermal stress exposure on JWA expression

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ming; CHEN Rui; LI Aiping; ZHOU Jianwei

    2007-01-01

    To investigate the expression of JWA after hemin and (or) thermal stress exposure,we treated K562 (chronic myelogenous leukemia cells) cells with different doses of hemin and thermal stress using different exposure times.The expression of JWA protein was determined by Western blot analysis.Reverse transcription-polymerase chain reaction was carried out to determine JWA mRNA expression.JWA promoter transcription activity analysis was performed by chloramphenicol acetyl transferase-enzyme linked immunosorbent assay (CAT-ELISA).The expression of JWA protein was significantly increased by up to (3.23 +0.57) folds compared to the control in K562 cells after hemin treatment (50 μM for one week),and a similar pattern was observed in the cells after treatment with thermal stress (42℃) for 2 hours [increased by (8.00+ 1.73) folds].The expression of JWA mRNA was also significantly elevated by up to (1.37 + 0.06)folds in K562 cells treated with hemin (30 μM for 48 hours),and a similar regulatory pattern [increased by (1.87±0.13)folds] was observed with thermal stress exposure (42℃) for 30 minutes.However,a combined antagonistic effect was observed in the treatment of K562 cells with hemin (30 μM,48 h) followed by thermal stress (42℃,30 min).CAT-ELISA further confirmed that either hemin or thermal stress treatment could up-regulate JWA transcription activity,however,the effects could be counteracted partly by treatment with a combination of both.Hemin and thermal stress might regulate JWA expression via distinct intracellular signal transduction pathways.

  3. Dust exposure and respiratory health effects in cement production.

    Science.gov (United States)

    Kakooei, Hossein; Gholami, Abdollah; Ghasemkhani, Mehdi; Hosseini, Mostapha; Panahi, Davoud; Pouryaghoub, Golamreza

    2012-01-01

    Dust can be produced by almost all production processes in Portland cement factory. Dust exposure potentially can affect respiratory function. But evidence for respiratory effect of cement dust exposure has not been conclusive. In this study we assessed effect of cement dust exposure on respiratory function in a cement production factory. A respiratory symptoms questionnaire was completed and pulmonary function tests were carried out on 94 exposed and 54 non exposed workers at a cement factory in the east of Iran. Additionally, respirable dust level was determined by the gravimetric method. X-ray fluorescence (XRF) technique was performed to determine the silica phases and the SiO(2) contents of the bulk samples. The arithmetic means (AM) of personal respirable dust were 30.18 mg/m(3) in the crushing, 27 mg/m(3) in the packing, 5.4 mg/m(3) in the cement mill, 5.9 mg/m(3) in the kiln and 5.48 mg/m(3) in the maintenance that were higher than threshold limit value (TLV) of the American Conference of Governmental Industrial Hygienists (ACGIH) which is 5 mg/m(3). This value in the unexposed group was 0.93 mg/m(3). In this study cough, sputum, wheezing and dyspnea were more prevalent among exposed subjects. Exposed workers compared to the unexposed group showed significant reduction in Forced Expiratory Volume in one second (FEV(1)), Forced Vital Capacity (FVC), and Forced Expiratory Flow between 25% and 75% of the FVC (FEF(25-75%)) (Pexposure and functional impairment among the cement factory workers. PMID:22359082

  4. Effect of prenatal exposure to kitchen fuel on birth weight

    Directory of Open Access Journals (Sweden)

    Yugantara Ramesh Kadam

    2013-01-01

    Full Text Available Background: Maternal exposure to kitchen fuel smoke may lead to impaired fetal growth. Objective: To study the effect of exposure to various kitchen fuels on birth weight. Methodology : Study type: Retrospective analytical. Study setting: Hospital based. Study Subjects: Mothers and their newborns. Inclusion Criteria: Mothers registered in first trimester with minimum 3 visits, non-anemic, full-term, and singleton delivery. Exclusion Criteria: History of Pregnancy Induced Hypertension (PIH, Diabetes Mellitus (DM, tobacco chewers or mishri users. Sample size: 328 mothers and their new-borne. Study period: Six months. Study tools: Chi-square, Z-test, ANOVA, and binary logistic regression. Results: Effect of confounders on birth weight was tested and found to be non-significant. Mean ± SD of birth weight was 2.669 ± 0.442 in Liquid Petroleium Gas (LPG users (n = 178, 2.465 ± 0.465 in wood users (n = 94, 2.557 ± 0.603 in LPG + wood users (n = 27 and 2.617 ± 0.470 in kerosene users (n = 29. Infants born to wood users had lowest birth weight and averagely 204 g lighter than LPG users (F = 4.056, P < 0.01. Percentage of newborns with low birth weight (LBW in wood users was 44.68% which was significantly higher than in LPG users (24.16%, LPG + wood users (40.74% and in kerosene users (34.48% (Chi-square = 12.926, P < 0.01. As duration of exposure to wood fuel increases there is significant decline in birth weight (F = 3.825, P < 0.05. By using logistic regression type of fuel is only best predictor. Conclusion: Cooking with wood fuel is a significant risk-factor for LBW, which is modifiable.

  5. [Environmental exposure to silver and its health effects].

    Science.gov (United States)

    Miyayama, Takamitsu; Arai, Yuta; Hirano, Seishiro

    2012-05-01

    Silver (Ag) possesses a well-known antibacterial activity and has been used for medical treatment and cosmetics such as wound dressing and deodorant powders. Occupational Safety and Health Administration (OSHA) and Mine Safety and Health Administration (MSHA) proposed that the permissible exposure limit (PEL) for both metallic and most soluble Ag compounds should be 0.01 mg/m3. Argyria and argyrosis are known to be caused by deposition of insoluble Ag in the dermis and cornea/conjunctiva. However, the metabolic behavior and biological roles of Ag have not been well characterized in mammals. Ag can be absorbed into the systemic circulation from drinking water, and also through parenteral routes such as inhalation and dermal exposure. Experimental studies have demonstrated that Ag+ induces and binds to metallothionein I and II (MTs), which are cysteine-rich proteins, in cells. MTs are major cytoplasmic metal binding proteins and thereby reduce cellular damage caused by toxic heavy metals including Ag. Profiles of Ag distribution in MTs and other Ag-binding proteins can be determined using high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS). This technique directly provides information on the intracellular behavior of Ag, which is important for elucidating the mechanism underlying Ag toxicity. Silver nanoparticles (AgNPs) are also commercially used mainly as antimicrobial agents. Despite the widespread use of AgNPs, relatively few studies have been undertaken to evaluate the health effects of AgNP exposure. In the present paper, we discuss the absorption, toxicodynamics, and metabolism of both Ag and AgNPs in mammals and their health effects.

  6. Exposure time-dependent thermal effects of radiofrequency electromagnetic field exposure on the whole body of rats.

    Science.gov (United States)

    Ohtani, Shin; Ushiyama, Akira; Maeda, Machiko; Hattori, Kenji; Kunugita, Naoki; Wang, Jianqing; Ishii, Kazuyuki

    2016-01-01

    We investigated the thermal effects of radiofrequency electromagnetic fields (RF-EMFs) on the variation in core temperature and gene expression of some stress markers in rats. Sprague-Dawley rats were exposed to 2.14 GHz wideband code division multiple access (W-CDMA) RF signals at a whole-body averaged specific absorption rate (WBA-SAR) of 4 W/kg, which causes behavioral disruption in laboratory animals, and 0.4 W/kg, which is the limit for the occupational exposure set by the International Commission on Non-Ionizing Radiation Protection guideline. It is important to understand the possible in vivo effects derived from RF-EMF exposures at these intensities. Because of inadequate data on real-time core temperature analyses using free-moving animal and the association between stress and thermal effects of RF-EMF exposure, we analyzed the core body temperature under nonanesthetic condition during RF-EMF exposure. The results revealed that the core temperature increased by approximately 1.5°C compared with the baseline and reached a plateau till the end of RF-EMF exposure. Furthermore, we analyzed the gene expression of heat-shock proteins (Hsp) and heat-shock transcription factors (Hsf) family after RF-EMF exposure. At WBA-SAR of 4 W/kg, some Hsp and Hsf gene expression levels were significantly upregulated in the cerebral cortex and cerebellum following exposure for 6 hr/day but were not upregulated after exposure for 3 hr/day. On the other hand, there was no significant change in the core temperature and gene expression at WBA-SAR of 0.4 W/kg. Thus, 2.14-GHz RF-EMF exposure at WBA-SAR of 4 W/kg induced increases in the core temperature and upregulation of some stress markers, particularly in the cerebellum. PMID:27665775

  7. Biological effects of low level exposures to chemicals and radiation

    International Nuclear Information System (INIS)

    In May 1990 a group of scientists representing several federal agencies, the International Society of Regulatory Toxicology and Pharmacology, the private sector, and academia met to develop a strategy to encourage the study of the biological effects of low level exposures (BELLE) to chemical agents and radioactivity. A workshop was held in 1991 with seven invited speakers focusing on the toxicological implications of biological adaptations. The selection of topics and speakers was designed to consider critically the concept of hormesis, not only in a broad, conceptual manner, but also at the molecular and biochemical levels. These presentations offered a complementary perspective on the diverse range of molecular mechanisms that can become activated at low levels of toxicant exposure. In addition to chemical toxicology research, an overview of current research on 'Effects of low-dose radiation on the immune response' was presented as well as 'Cellular adaptation as an important response during chemical carcinogenesis'. The final presentation was devoted to biostatistical considerations when designing studies that address issues associated with the biological responses to low doses of chemicals and radiation, as well as issues in interpretation of the findings from such studies

  8. Neurobehavioural Effects of Hypergravity Exposure in CD-1 Mice

    Science.gov (United States)

    Santucci, Daniela; Francia, Nadia; Aloe, Luigi; Enrico, Alleva

    The effects of spaceflight on the nervous system physiology could have important implications for the prolonged stay outside Earth's gravitational field. In this view, both ground-based and space research using animal models represent useful tools to investigate the impact of gravity (hypergravity, microgravity and weightlessness) on the nervous system and behaviour. Data coming from these studies, besides acquisition of knowledge relevant for spaceflights and pro-longed permanence of both humans and animals in space, could provide insight into basic bio-logical phenomena underlying the plasticity of the nervous system and its adaptive responses to a changing environment. Most ground experiments employing animal models use the paradigm of hypergravity exposure with the expectation that behavioural and physiological reactions to this environment might help to explain reactions to the microgravity challenge faced by or-biting animals. An overview of ground-based experiments set up to investigate the effects of changes of gravitational environment on the neurobehavioural responses of CD-1 mouse will be reported, and will illustrate the short-, medium-and long-term behavioural and neurobiological consequences of hypergravity exposure both at adulthood and during early and late postnatal development. Moreover, since mother-pup interaction is critical for the survival and the devel-opment of neonatal rodents, especially in an extreme environment such as that of space, we characterized, exploiting ethological methods, changes in maternal behaviour of CD-1 outbred mouse dams exposed to mild hypergravity. The results of these experiments will be discussed.

  9. Exposure-effect relations between aircraft and road traffic noise exposure at school and reading comprehension: the RANCH project.

    OpenAIRE

    Clark, Charlotte; Martin, Rocio; van Kempen, Elise; Alfred, Tamuno; Head, Jenny; Davies, Hugh W.; Haines, Mary M; Lopez Barrio, Isabel; Matheson, Mark; Stansfeld, Stephen A

    2006-01-01

    Transport noise is an increasingly prominent feature of the urban environment, making noise pollution an important environmental public health issue. This paper reports on the 2001-2003 RANCH project, the first cross-national epidemiologic study known to examine exposure-effect relations between aircraft and road traffic noise exposure and reading comprehension. Participants were 2,010 children aged 9-10 years from 89 schools around Amsterdam Schiphol, Madrid Barajas, and London Heathrow airp...

  10. Tobacco and Pregnancy: Overview of exposures and effects

    Science.gov (United States)

    This opening paper will review the epidemiology of the impact of cigarette smoking and other forms of tobacco exposure on human development. Sources of exposure described include cigarettes and other forms of smoked tobacco, secondhand (environmental) tobacco smoke, several forms...

  11. Late biological effects from internal and external exposure

    Energy Technology Data Exchange (ETDEWEB)

    Adams, W.H.

    1985-01-01

    Information on late biological effects of radiation was obtained from the long-term medical followup of a small population of Marshallese accidentally exposed to radioactive fallout from a thermonuclear test in 1954. Endocrine data are compatible with a sequence of nonstochastic radiation effects. The ingestion of radioisotopes of iodine produced clinical thyroid hypofunction in children, biochemical evidence of thyroid dysfunction in some adults, thyroid adenomatous module formation, and, as a possible indirect effect of thyroid damage, at least two cases of pituitary adenoma. In contrast, the only evidence of a stochastic effect has been a real increase in thyroid cancers among the more highly exposed people of Rongelap, none of whom have evidence of residual disease. While three nonthyroidal cancers which are known to be inducible in humans by external irradiation have been documented in the exposed population, three similar cancers have occurred in an unexposed comparison population of Marshallese. Nonstochastic effects of radiation exposure may be common but subtle. In the Marshallese experience the morbidity of delayed nonstochastic effects far exceeds that of the stochastic. 20 refs., 5 figs., 1 tab.

  12. Late biological effects from internal and external exposure

    International Nuclear Information System (INIS)

    Information on late biological effects of radiation was obtained from the long-term medical followup of a small population of Marshallese accidentally exposed to radioactive fallout from a thermonuclear test in 1954. Endocrine data are compatible with a sequence of nonstochastic radiation effects. The ingestion of radioisotopes of iodine produced clinical thyroid hypofunction in children, biochemical evidence of thyroid dysfunction in some adults, thyroid adenomatous module formation, and, as a possible indirect effect of thyroid damage, at least two cases of pituitary adenoma. In contrast, the only evidence of a stochastic effect has been a real increase in thyroid cancers among the more highly exposed people of Rongelap, none of whom have evidence of residual disease. While three nonthyroidal cancers which are known to be inducible in humans by external irradiation have been documented in the exposed population, three similar cancers have occurred in an unexposed comparison population of Marshallese. Nonstochastic effects of radiation exposure may be common but subtle. In the Marshallese experience the morbidity of delayed nonstochastic effects far exceeds that of the stochastic. 20 refs., 5 figs., 1 tab

  13. Acute effects of exposure to 56Fe and 16O particles on learning and memory

    Science.gov (United States)

    Although it has been shown that exposure to HZE particles disrupts cognitive performance when tested 2-4 weeks after irradiation, it has not been determined whether exposure to HZE particles can exert acute effects on cognitive performance; i.e., effects within 4-48 hrs after exposure. The present ...

  14. Effects of Subchronic Aluminum Exposure on Liver Function in Rats

    Institute of Scientific and Technical Information of China (English)

    Bai Chong-sheng; Wang Fan; Zhao Han-song; Li Yan-fei

    2012-01-01

    Effects of subchronic aluminum (Al) exposure on the function of rat liver were investigated in this experiment. A total of 48 male Wistar rats (4 weeks old) were randomly divided into four groups: experimental groups were orally exposed to 64.18, 128.36, 256.72 mg. kg^-1 body weight aluminum trichloride (AlCl3) in drinking water, and the control group with distilled water. The experiment lasted for 120 days. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), the concentration of malondialdehyde (MDA) in serum and liver, and alanine transarninase (ALT) and aspartate aminotransferase (AST) activities in serum were detected in all groups. The results showed that the activities of ALT, AST in serum and the concentrations of MDA in liver in the Al-treated groups significantly increased compared with the control group; the activities of GSH-PX and SOD in high-dose Al-treated group were significantly lower than those in control group. Our findings indicated that subchronic AI exposure could result in injures of lipid peroxidation and function in liver.

  15. Landscape parameters driving aquatic pesticide exposure and effects

    International Nuclear Information System (INIS)

    Pesticide contamination is considered one of the reasons streams fail to achieve good ecological and chemical status, the main objectives of the Water Framework Directive. However, little is known on the interaction of different pesticide sources and landscape parameters and the resulting impairment of macroinvertebrate communities. We evaluated the potential effects of diffuse and point sources of pesticides using macroinvertebrate monitoring data from 663 sites in central Germany. Additionally, we investigated forested upstream reaches and structural quality as landscape parameters potentially mitigating or amplifying the effects of pesticides. Diffuse pesticide pollution and forested upstream reaches were the most important parameters affecting macroinvertebrate communities (pesticide-specific indicator SPEARpesticides). Our results indicate that forested upstream reaches and riparian buffer strips at least 5 m in width can mitigate the effects and exposure of pesticides. In addition, we developed a screening approach that allows an initial, cost-effective identification of sites of concern. Highlights: • Pesticide sources and landscape parameters important for holistic risk assessment. • Riparian buffer strips of at least 5 m in width can reduce diffuse pesticide input. • Forested upstream reaches enhance recovery of pesticide-affected communities. • Screening approach allows quick and cost-effective identification of problem sites. -- Our results show the interaction of different pesticide sources and landscape parameters and the resulting impairment of macroinvertebrate communities

  16. The influence of print exposure on the body-object interaction effect in visual word recognition

    OpenAIRE

    Dana eHansen; Paul D Siakaluk; Penny M Pexman

    2012-01-01

    We examined the influence of print exposure on the body-object interaction (BOI) effect in visual word recognition. High print exposure readers and low print exposure readers either made semantic categorizations (Is the word easily imageable?; Experiment 1) or phonological lexical decisions (Does the item sound like a real English word?; Experiment 2). The results from Experiment 1 showed that there was a larger facilitatory BOI effect for the low print exposure readers than for the high prin...

  17. Late health effects of chronic radiation exposure of bone marrow

    Energy Technology Data Exchange (ETDEWEB)

    Yarmoshenko, Ilia V.; Malinovsky, Georgy P.; Konshina, Lidia G.; Zhukovsky, Michael V. [Institute of Industrial Ecology UB RAS, 620219, 20, Sophy Kovalevskoy St., Ekaterinburg (Russian Federation); Tuzankina, Irina A. [Institute of Immunology and Physiology UB RAS, 620049, 106, Pervomayskaya St., Ekaterinburg (Russian Federation)

    2014-07-01

    Accidental explosion of waste storage tank at former soviet plutonium production plant 'Mayak' in 1957 resulted in emission of considerable amount of radioactive substances to the atmosphere. Atmospheric transfer and fallout caused contamination of the environment by Sr-90 and short-lived radionuclides (East-Ural Radioactive Trace, EURT). Due to consumption of contaminated food and milk some internal organs were affected to relatively high radiation exposure. Archive data of causes of deaths of rural population of EURT northern part for period 1957-2000 were used to create the Register on causes of deaths. Register records related to the settlements where initial surface contamination by Sr-90 was above and below 3.7 kBq/m2 were included to exposed (4 844 records) and unexposed (6 158 records) group respectively. Basing on the Register the analysis of cancer and non-cancer health effects of radiation exposure was conducted. By estimating proportionate mortality ratios statistically significant excess mortality due to the groups of causes of death as follow was observed in exposed population: stomach, liver and cervix cancers; group consisted only of stomach cancer; non-cancer deceases of infectious etiology. Non-significant but remarkably high risk was observed for the following groups of causes of death: bone cancer; leukemia; liver cancer; cervix cancer. Insignificant, virtually zero risk was found for: non-gastrointestinal solid cancers; colon and lung cancers; non-infectious non-cancer deceases. At the same time, considerable radiation doses were absorbed in bone (mean bone surface dose about 0.1 Gy) and colon (mean dose about 0.07 Gy). Doses absorbed in other organs and tissues were negligible and amounted less than 0.01 Gy for most tissues. It can be seen that some disagreement between observed effects and absorbed doses is revealed. Most remarkable is the high excess risks of stomach, liver and cervix cancers as well as non-cancer deceases of

  18. Biological effects of exposure to magnetic resonance imaging: an overview

    Directory of Open Access Journals (Sweden)

    Formica Domenico

    2004-04-01

    Full Text Available Abstract The literature on biological effects of magnetic and electromagnetic fields commonly utilized in magnetic resonance imaging systems is surveyed here. After an introduction on the basic principles of magnetic resonance imaging and the electric and magnetic properties of biological tissues, the basic phenomena to understand the bio-effects are described in classical terms. Values of field strengths and frequencies commonly utilized in these diagnostic systems are reported in order to allow the integration of the specific literature on the bio-effects produced by magnetic resonance systems with the vast literature concerning the bio-effects produced by electromagnetic fields. This work gives an overview of the findings about the safety concerns of exposure to static magnetic fields, radio-frequency fields, and time varying magnetic field gradients, focusing primarily on the physics of the interactions between these electromagnetic fields and biological matter. The scientific literature is summarized, integrated, and critically analyzed with the help of authoritative reviews by recognized experts, international safety guidelines are also cited.

  19. Effective exposure level and diagnostic performance in endodontic radiography

    International Nuclear Information System (INIS)

    Image quality is limited by the information capacity of the image-forming system and can be computed from three parameters: contrast, resolution, and noise. These parameters can be combined to yield a single measure which determines the maximum amount of information obtainable from any x-ray system and is called the noise-equivalent number of quanta (NEQ) per unit area. The effects of image quality, expressed as noise-equivalent number of quanta (NEQ) per unit area, on the radiographic performance by dentists reading the position of an endodontic file in a root canal were studied. Three different speed films were used in conjunction with a fixed screen. Components of variance associated with the position of the tooth apex and the tip of an endodontic file in a root canal were compared for the effect of different NEQs and observers. Results show that the standard deviation in locating a file tip and tooth apex may be a linear function of log NEQ. These findings indicate that a significant reduction in exposure would have a relatively small effect on the precision of endodontic distance measurements

  20. Effective exposure level and diagnostic performance in endodontic radiography

    Energy Technology Data Exchange (ETDEWEB)

    Okano, T.; Wiebe, J.D.; Webber, R.L.; Wagner, R.F.

    1983-05-01

    Image quality is limited by the information capacity of the image-forming system and can be computed from three parameters: contrast, resolution, and noise. These parameters can be combined to yield a single measure which determines the maximum amount of information obtainable from any x-ray system and is called the noise-equivalent number of quanta (NEQ) per unit area. The effects of image quality, expressed as noise-equivalent number of quanta (NEQ) per unit area, on the radiographic performance by dentists reading the position of an endodontic file in a root canal were studied. Three different speed films were used in conjunction with a fixed screen. Components of variance associated with the position of the tooth apex and the tip of an endodontic file in a root canal were compared for the effect of different NEQs and observers. Results show that the standard deviation in locating a file tip and tooth apex may be a linear function of log NEQ. These findings indicate that a significant reduction in exposure would have a relatively small effect on the precision of endodontic distance measurements.

  1. Effect of exposure on material response of a swelling elastomer

    Directory of Open Access Journals (Sweden)

    T. Pervez

    2009-06-01

    suitability of these elastomers for downhole applications. Material properties after swelling can be used by designers using FEM or other numerical simulation methods for improvement of elastomer-based sealing and packer design. Comparison of fresh and exposed elastomer samples highlights the significant change in material response due to exposure.Originality/value: The paper presents a comparison between material properties of fresh and exposed samples of the same water-swelling elastomer. Such a comparative study, highlighting the effect of exposure on material response of an elastomer, has not been carried out before.

  2. Effects of exposure to different types of radiation on behaviors mediated by peripheral or central systems

    Science.gov (United States)

    Rabin, B. M.; Joseph, J. A.; Erat, S.

    The effects of exposure to ionizing radiation on behavior may result from effects on peripheral or on central systems. For behavioral endpoints that are mediated by peripheral systems (e.g., radiation-induced conditioned taste aversion or vomiting), the behavioral effects of exposure to heavy particles (^56Fe, 600 MeV/n) are qualitatively similar to the effects of exposure to gamma radiation (^60Co) and to fission spectrum neutrons. For these endpoints, the only differences between the different types of radiation are in terms of relative behavioral effectiveness. For behavioral endpoints that are mediated by central systems (e.g., amphetamine-induced taste aversion learning), the effects of exposure to ^56Fe particles are not seen following exposure to lower LET gamma rays or fission spectrum neutrons. These results indicate that the effects of exposure to heavy particles on behavioral endpoints cannot necessarily be extrapolated from studies using gamma rays, but require the use of heavy particles.

  3. Human Exposure to Butylbenzyl Phthalate: A source-effect chain approach

    NARCIS (Netherlands)

    Effting SE; Veen MP van; LBO

    1998-01-01

    The human exposure to Butylbenzyl phthalate (BBP) is estimated using a source-effect chain approach. Exposure is both indirect (via the environment) and direct (via consumer products and at the working place of a vinyl manufacturer). Exposure via the environment is estimated with use of the EUSES mo

  4. Exposure to pesticides of fruit growers and effects on reproduction: an epidemiological approach.

    NARCIS (Netherlands)

    Cock, de J.S.

    1995-01-01

    In this thesis the exposure to pesticides of fruit growers in The Netherlands was studied as well as its relation to reproductive health effects. The most commonly used fungicide, captan, was used as a marker for exposure. Several exposure studies were carried out during application of captan, and w

  5. Long-Term Effects of Neonatal Single or Multiple Isoflurane Exposures on Spatial Memory in Rats

    OpenAIRE

    Murphy, Kathy L.; Baxter, Mark G.

    2013-01-01

    General anesthetics are neurotoxic to neonatal rodents and non-human primates. Neonatal exposure to general anesthetics has been associated with long-term cognitive deficits in animal models. Some data from humans are consistent with long-term deleterious effects of anesthetic exposure early in life on cognitive development, with multiple exposures to general anesthetics being particularly damaging. We sought to determine whether repeated exposure of neonatal rats to anesthesia was associated...

  6. Hearing in young adults, part II: the effects of recreational noise exposure

    OpenAIRE

    Hannah Keppler; Ingeborg Dhooge; Bart Vinck

    2015-01-01

    Great concern arises from recreational noise exposure, which might lead to noise-induced hearing loss in young adults. The objective of the current study was to evaluate the effects of recreational noise exposure on hearing function in young adults. A questionnaire concerning recreational noise exposures and an audiological test battery were completed by 163 subjects (aged 18-30 years). Based on the duration of exposure and self-estimated loudness of various leisure-time activities, the weekl...

  7. Long-term effects of neonatal single or multiple isoflurane exposures on spatial memory in rats

    OpenAIRE

    MarkGBaxter; KathyLMurphy

    2013-01-01

    General anesthetics are neurotoxic to neonatal rodents and nonhuman primates. Neonatal exposure to general anesthetics has been associated with long-term cognitive deficits in animal models. Some data from humans are consistent with long-term deleterious effects of anesthetic exposure early in life on cognitive development, with multiple exposures to general anesthetics being particularly damaging. We sought to determine whether repeated exposure of neonatal rats to anesthesia was associated...

  8. Exposure-effect relations between aircraft and road traffic noise exposure at school and reading comprehension: the RANCH project.

    NARCIS (Netherlands)

    Clark, Charlotte; Martin, Rocio; Kempen, Elise van; Alfred, Tamuno; Head, Jenny; Davies, Hugh W; Haines, Mary M; Lopez Barrio, Isabel; Matheson, Mark; Stansfeld, Stephen A

    2006-01-01

    Transport noise is an increasingly prominent feature of the urban environment, making noise pollution an important environmental public health issue. This paper reports on the 2001-2003 RANCH project, the first cross-national epidemiologic study known to examine exposure-effect relations between air

  9. Linking Aquatic Exposure and Effects: Risk Assessment of Pesticides

    NARCIS (Netherlands)

    Brock, T.C.M.; Alix, A.; Brown, C.D.; Capri, E.; Gottesburen, E.

    2010-01-01

    Time-variable exposure profiles of pesticides are more often the rule than exception in the surface waters of agricultural landscapes. There is, therefore, a need to adequately address the uncertainties arising from time-variable exposure profiles in the aquatic risk assessment procedure for pestici

  10. Effects of prenatal exposure to chronic mild stress and toluene in rats

    DEFF Research Database (Denmark)

    Hougaard, Karin; Andersen, Maibritt B; Hansen, Ase M;

    2005-01-01

    The aim of the present study was to elucidate whether prenatal chronic stress, in combination with exposure to a developmental neurotoxicant, would increase effects in the offspring compared with the effects of either exposure alone. Development and neurobehavioral effects were investigated in fe...

  11. Occupational exposure and effects on the male reproductive system

    Directory of Open Access Journals (Sweden)

    Queiroz Erika Kaltenecker Retto de

    2006-01-01

    Full Text Available A significant increase in the incidence of male infertility has been described in the international literature, raising questions about its causes. Part of this effect may result from synthetic toxic substances acting on the endocrine system (endocrine disruptors, many of which are routinely used in work processes. We provide a critical review of the specialized literature on work-related chemical substances capable of causing male infertility. Pesticides such as DDT, linuron, and others, heavy metals like mercury, lead, cadmium, and copper, and substances from various industrial uses and residues such as dioxins, polychlorinated biphenyls (PCBs, ethylene dibromide (EDB, phthalates, polyvinyl chloride (PVC, and ethanol are among the main endocrine disruptors that can cause male infertility. Based on the literature, gonadal dysfunction and congenital malformation are the main alterations caused by these substances in the male reproductive system. We conclude that despite the relative lack of studies on this issue, the relevance of such risk calls for further studies as well as measures to prevent workers' exposure to the various substances.

  12. Effect of exposure to diazinon on adult rat's brain.

    Science.gov (United States)

    Rashedinia, Marzieh; Hosseinzadeh, Hossein; Imenshahidi, Mohsen; Lari, Parisa; Razavi, Bibi Marjan; Abnous, Khalil

    2016-04-01

    Diazinon (DZN), a commonly used agricultural organophosphate insecticide, is one of the major concerns for human health. This study was planned to investigate neurotoxic effects of subacute exposure to DZN in adult male Wistar rats. Animals received corn oil as control and 15 and 30 mg/kg DZN orally by gastric gavage for 4 weeks. The cerebrum malondialdehyde and glutathione (GSH) contents were assessed as biomarkers of lipid peroxidation and nonenzyme antioxidants, respectively. Moreover, activated forms of caspase 3, -9, and Bax/Bcl-2 ratios were evaluated as key apoptotic proteins. Results of this study suggested that chronic administration of DZN did not change lipid peroxidation and GSH levels significantly in comparison with control. Also, the active forms of caspase 3 and caspase 9 were not significantly altered in DZN-treated rat groups. Moreover, no significant changes were observed in Bax and Bcl-2 ratios. This study indicated that generation of reactive oxygen species was probably modulated by intracellular antioxidant system. In conclusion, subacute oral administration of DZN did not alter lipid peroxidation. Moreover, apoptosis induction was not observed in rat brain. PMID:24217015

  13. Immunobiological effect of bitemporal exposure of rabbits to microwaves

    Energy Technology Data Exchange (ETDEWEB)

    Bogolyubov, V.M.; Pershin, S.B.; Frenkel' , I.D.; Sidorov, V.D.; Galenchik, A.I.; Ponomarev, Yu.T.; Bobkova, A.S.; Kuz' min, S.N.; Moshiashvili, I.Ya.; Kozlova, N.N.; Korovkina, E.G.; Agibalov, Yu.V.

    1987-01-01

    The authors investigate the effects of microwave radiation on the immunological behavior of the thyroid and various hormones of rabbits. Irradiation was carried out on the heads of the animals. They were then divided into four groups depending on the period of exposure. The number of hemolysis-forming cells against sheep red blood cells and the concentration of serum immunoglobulins were determined. Levels of TSH, triiodothyronine, thyroxine, testosterone and prostaglandins in serum or blood plasma were determined by radioimmunoassay and the concentration of total 11-hydroxycorticosteroids in the adrenals and plasma were determined by fluorimetry. Microwave radiation of the temporo-parietal region of the head was found to decrease the number of background hemolysis-forming cells. An increase in glucocorticoid function was recorded. Thyroid function was depressed. The plasma 11-hydroxycorticosteroid level was significantly raised. It is concluded in general that microwave irradiation leads to activation of the hypothalamo-hypophyseo-adrenal system with consequent enhancement of the glucocorticoid function of the adrenal cortex and depression of thyroid function.

  14. The effect of chronic exposure to fatty acids

    DEFF Research Database (Denmark)

    Xiao, J.; Gregersen, S.; Kruhøffer, Mogens;

    2001-01-01

    . In conclusion, chronic exposure to low palmitate alters insulin secretion as well as gene expression. The number of genes that changed expression was palmitate dose and exposure time dependent. Randle's fatty acid-glucose cycle seems to be operative on the gene transcription level. A modification of expression...... found that basal insulin secretion increased in cells exposed to palmitate. The response to glucose stimulation declined on d 44 in cells cultured at 200 microM palmitate. In response to 50 and 200 microM palmitate exposure, expression was changed in 11 and 99 genes on d 2 and 134 and in 159 genes on d...

  15. The effects of repeated low-dose sarin exposure

    International Nuclear Information System (INIS)

    This project assessed the effects of repeated low-dose exposure of guinea pigs to the organophosphorus nerve agent sarin. Animals were injected once a day, 5 days per week (Monday-Friday), for 2 weeks with fractions (0.3x, 0.4x, 0.5x, or 0.6x) of the established LD5 dose of sarin (42 μg/kg, s.c.). The animals were assessed for changes in body weight, red blood cell (RBC) acetylcholinesterase (AChE) levels, neurobehavioral reactions to a functional observational battery (FOB), cortical electroencephalographic (EEG) power spectrum, and intrinsic acetylcholine (ACh) neurotransmitter (NT) regulation over the 2 weeks of sarin exposure and for up to 12 days postinjection. No guinea pig receiving 0.3, 0.4 or 0.5 x LD5 of sarin showed signs of cortical EEG seizures despite decreases in RBC AChE levels to as low as 10% of baseline, while seizures were evident in animals receiving 0.6 x LD5 of sarin as early as the second day; subsequent injections led to incapacitation and death. Animals receiving 0.5 x LD5 sarin showed obvious signs of cholinergic toxicity; overall, 2 of 13 animals receiving 0.5 x LD5 sarin died before all 10 injections were given, and there was a significant increase in the angle of gait in the animals that lived. By the 10th day of injection, the animals receiving saline were significantly easier to remove from their cages and handle and significantly less responsive to an approaching pencil and touch on the rump in comparison with the first day of testing. In contrast, the animals receiving 0.4 x LD5 sarin failed to show any significant reductions in their responses to an approaching pencil and a touch on the rump as compared with the first day. The 0.5 x LD5 sarin animals also failed to show any significant changes to the approach and touch responses and did not adjust to handling or removal from the cage from the first day of injections to the last day of handling. Thus, the guinea pigs receiving the 0.4 and 0.5 x LD5 doses of sarin failed to

  16. Effects of Acute Exposures to Carbon Dioxide Upon Cognitive Functions

    Science.gov (United States)

    Scully, R. R.; Alexander, D. J.; Ryder, V. E.; Lam, C. W.; Statish, U.; Basner, M.

    2016-01-01

    Large quantities of carbon dioxide (CO2) originate from human metabolism and typically, within spacecraft, remain about 10-fold higher in concentration than at the earth's surface. There have been recurring complaints by crew members of episodes of "mental viscosity" adversely affecting their performance, and there is evidence from the International Space Station (ISS) that associates CO2 levels with reports of headaches by crewmembers. Additionally, there is concern that CO2 may contribute to vision impairment and intracranial pressure that has been observed in some crewmembers. Consequently, flight rules have been employed to control the level of CO2 below 4 mm Hg, which is well below the existing Spacecraft Maximum Allowable Concentration (SMAC) of 10 mm Hg for 24-hour exposures, and 5.3 mm Hg for exposures of 7 to 180 days. However, the flight rule imposed limit, which places additional demands upon resources and current technology, still exceeds the lower bound of the threshold range for reportable headaches (2 - 5 mm Hg). Headaches, while sometime debilitating themselves, are also symptoms that can provide evidence that physiological defense mechanisms have been breached. The causes of the headaches may elicit other subtle adverse effects that occur at CO2 levels well below that for headaches. The concern that CO2 may have effects at levels below the threshold for headaches appears to be substantiated in unexpected findings that CO2 at concentrations below 2 mm Hg substantially reduced some cognitive functions that are associated with the ability to make complex decisions in conditions that are characterized by volatility, uncertainty, complexity, ambiguity, and delayed feedback. These are conditions that could be encountered by crews in off-nominal situations or during the first missions beyond low earth orbit. If findings of the earlier study are confirmed in crew-like subjects, our findings would provide additional evidence that CO2 may need to be

  17. Prandial effect on the systemic exposure of amisulpride.

    Science.gov (United States)

    Jang, Yoo-Jung; Jeong, Tae Cheon; Noh, Keumhan; Baek, In-Whan; Kwon, Kwang-il; Kim, Eunyoung; Yoon, Young-Ran; Kang, Wonku

    2014-10-01

    A substituted benzamide, amisulpride is an atypical antipsychotic and a specific antagonist for dopamine D2 and D3 receptors. The prandial effect on amisulpride absorption remains unclear, therefore, this study was designed to investigate the effect of food on the systemic exposure to amisulpride in healthy volunteers. The study was a randomized, two-way crossed trial in which a single oral dose of amisulpride was administered on two occasions, with 7-days washout period between each drug administration. The volunteers were randomly divided into two groups and received amisulpride (50 mg) with Korean traditional food or under fasting state. Blood was serially taken, and the plasma amisulpride concentrations were measured by LC/MS/MS. At fasting state, amisulpride reached the first peak (37.1 ± 13.3 ng/ml) at ~2.3 h, and decreased down to 19.4 ± 4.3 ng/ml until 3.5 h, and then again went up to the second peak (25.3 ± 5.8 ng/ml) at 5 h followed by a slow decay with 10.6 h of half-life. In contrast, no double peaks were shown when the drug was given with meal. The maximum concentration of amisulpride (56.0 ± 12.7 ng/ml) was increased by a 1.5-fold compared with that under fasting (p > 0.05), and the time to peak shortened a little (1.7 ± 0.6 h).

  18. Effects of hyperlipidemia on adaptive responses to repeated zinc exposure

    Science.gov (United States)

    In individuals with underlying atherosclerosis and coronary heart disease (CHD), exposure to near-road air pollution correlates epidemiologically with deleterious health outcome. Associated cardiotoxicity purportedly involves generation of reactive oxygen species (ROS) and activa...

  19. Metabolic effects of chronic ozone exposure on rats

    Energy Technology Data Exchange (ETDEWEB)

    Hathway, J.A.; Terrill, R.E.

    1962-01-01

    Rats were exposed to 0.8 to 1.5 ppm O/sub 3/ for 6 hr/day, 4 days/wk for 19 weeks. Lower titratable acidity after 91 days exposure and higher urine pH after 98 days exposure were observed. No significant differences in urine creatine, creatinine, uric acid/creatinine, or amino acid/creatinine were observed. pH differences suggest respiratory alkalosis, possibly due to subjectively noticed hyperventilation in exposed group.

  20. Field acquisition system of signals produced by 60 Hz electric power distribution networks; Sistema de aquisicao em campo de sinais produzidos por redes eletricas de 60 Hz

    Energy Technology Data Exchange (ETDEWEB)

    Arasaki, Arnaldo Takashi

    1996-12-31

    Signal acquisition and analysis problems generally require expensive instruments whose utilization may be optimized through the use of portable signal acquisition modules with signal storage capability. Signals could be registered where they are generated and then analyzed properly in a laboratory far away. A portable acquisition module is developed after studying promising solutions such as direct analog storage, analog-to-digital binary conversion and delta modulation of the collected signals. Since some years ago, a solid state non-volatile analog memory has been commercially available and it was chosen in this portable module design. It also provides low power consumption, turning out to be interesting to signal acquisition and storage applications. This work also presents the portable acquisition module results. (author) 100 refs., 48 figs., 7 tabs.

  1. Listen, Learn, Like! Dorsolateral Prefrontal Cortex Involved in the Mere Exposure Effect in Music

    OpenAIRE

    Anders C. Green; Bærentsen, Klaus B.; Hans Stødkilde-Jørgensen; Andreas Roepstorff; Peter Vuust

    2012-01-01

    We used functional magnetic resonance imaging to investigate the neural basis of the mere exposure effect in music listening, which links previous exposure to liking. Prior to scanning, participants underwent a learning phase, where exposure to melodies was systematically varied. During scanning, participants rated liking for each melody and, later, their recognition of them. Participants showed learning effects, better recognising melodies heard more often. Melodies heard most often were mos...

  2. Multiple exposure routes of a pesticide exacerbate effects on a grazing mayfly.

    Science.gov (United States)

    Pristed, Mathias Joachim Skov; Bundschuh, Mirco; Rasmussen, Jes Jessen

    2016-09-01

    Hydrophobic pesticides such as pyrethroid insecticides tend to occur in their soluble form mainly as transient pulses in streams. In addition, they are regularly detected in significant quantities adsorbed to stream sediments and other organic in-stream structures. Consequently, stream biota is likely subjected to pesticide exposure via multiple routes. In this study we aimed at investigating the influence of exposure routes for the pyrethroid insecticide lambda-cyhalothrin on the grazing mayfly Heptagenia sulphurea. Therefore, H. sulphurea was exposed to lambda-cyhalothrin via single- (water or biofilm) or biphasic exposure (water and biofilm) at environmentally realistic concentrations (0, 0.1, 1μgL(-1)) and exposure duration (2h) in a full factorial design (n=5). Mortality, moulting frequency, and biofilm accrual (proxy for feeding rate) were recorded subsequent to a 7 d post exposure period. Mortality significantly increased and moulting frequency significantly decreased with increasing concentrations of lambda-cyhalothrin in the water phase whereas exposure via biofilm prompted no significant effects on these endpoints (α=0.05). Effect predictions systematically underestimated and overestimated effects for mortality and moulting frequency, respectively. Similarly, mayfly feeding rate was significantly reduced by water phase exposure whereas pre-exposed biofilm did not significantly affect this variable. However, we found a significant but non-systematic interaction between water phase and biofilm exposure on mayfly feeding rate. Our results show that exposure to the same pesticide via multiple exposure routes may increase the magnitude of effects beyond the level predicted from single phase exposures which has clear implications for the aquatic risk assessment of hydrophobic pesticides. However, our results additionally reveal that interactions between pesticide exposure routes may vary between selected dependent variables. We emphasize that unravelling the

  3. Effects of Classroom Acoustics and Self-Reported Noise Exposure on Teachers' Well-Being

    Science.gov (United States)

    Kristiansen, Jesper; Persson, Roger; Lund, Soren Peter; Shibuya, Hitomi; Nielsen, Per Moberg

    2013-01-01

    Beyond noise annoyance and voice problems, little is known about the effects that noise and poor classroom acoustics have on teachers' health and well-being. The aim of this field study was therefore to investigate the effects of perceived noise exposure and classroom reverberation on measures of well-being. Data on self-reported noise exposure,…

  4. Potential health effects of exposure to carcinogenic compounds in incense smoke in temple workers.

    Science.gov (United States)

    Navasumrit, Panida; Arayasiri, Manasawee; Hiang, Ohmar May Tin; Leechawengwongs, Manoon; Promvijit, Jeerawan; Choonvisase, Suppachai; Chantchaemsai, Samroeng; Nakngam, Netnapa; Mahidol, Chulabhorn; Ruchirawat, Mathuros

    2008-05-01

    Incense smoke is a potential hazard to human health due to various airborne carcinogens emitted from incense burning. This study aimed to evaluate the potential health effects of exposure to benzene, 1,3-butadiene, and polycyclic aromatic hydrocarbons (PAHs) emitted from incense smoke in temple workers. Exposure and health risks were assessed through the measurement of ambient exposure as well as through the use of biomarkers of exposure and early biological effects. Ambient air measurement showed that incense burning generates significantly higher levels of airborne benzene (Pincense burning may increase health risk for the development of cancer in temple workers.

  5. Evaluation of effects of ozone exposure on influenza infection in mice using several indicators of susceptibility.

    Science.gov (United States)

    Selgrade, M K; Illing, J W; Starnes, D M; Stead, A G; Ménache, M G; Stevens, M A

    1988-07-01

    Mice were exposed to 1 ppm O3, 3 hr/day, for 5 consecutive days. Separate groups of mice were infected with influenza following each of the individual exposures. A twofold increase in the incidence of mortality and a 3-day decrease in mean survival time were observed in mice infected after the second exposure. There were no effects on percentage mortality or mean survival time due to exposure to 1 ppm O3 in mice infected after the first, third, fourth, or fifth exposure. When the exposure concentration was lowered to 0.5 ppm, there were no effects on mortality in mice infected after the second exposure. Five, daily, 3-hr exposures to 1 ppm O3 had no effect on virus titers in the lungs of mice infected after either the second or fifth exposure. In contrast, wet lung weights were significantly enhanced over infected air controls in mice infected after the second O3 exposure at both 1 and 0.5 ppm but not at 0.25 ppm exposure concentrations. This effect on lung wet weight was observed in mice infected with a dose of virus which produced 7-33% mortality in controls as well as in mice infected with a sublethal dose of virus. Histopathologic changes due to sublethal influenza infection, including nonsuppurative pneumonitis and necrosis, squamous metaplasia and hyperplasia of the epithelium lining the bronchi and bronchioles, were more severe in mice infected after the second of five, 1 ppm O3 exposure than in comparable air controls. Sublethal infection caused a loss of lung volume with secondary reduction in diffusing capability and homogenity of ventilation distribution. These latter two effects were also exacerbated in mice infected after the second of five, 1 ppm O3 exposures as compared to air controls. When mice were infected after the fifth, 1 ppm O3 exposure, there was no effect due to ozone on either lung wet weight or histopathology. The data indicate that O3 has little if any effect on antiviral defense mechanisms since virus titers in the lungs were not

  6. Acute and chronic respiratory effects of occupational exposure to ammonia.

    Science.gov (United States)

    Holness, D L; Purdham, J T; Nethercott, J R

    1989-12-01

    In a soda ash plant, 58 workers exposed to mean airborne ammonia levels of 9.2 +/- 1.4 ppm were compared with 31 control workers with a mean exposure of 0.3 +/- 0.1 ppm. There were no differences between the groups in the reporting of respiratory or cutaneous symptoms, sense of smell, baseline lung function, or change in lung function over a work shift at the beginning and end of a workweek. No relationships between level or length of ammonia exposure and lung function results were demonstrated. PMID:2596404

  7. Chlorpyrifos exposure in farmers and urban adults: Metabolic characteristic, exposure estimation, and potential effect of oxidative damage.

    Science.gov (United States)

    Wang, Lei; Liu, Zhen; Zhang, Junjie; Wu, Yinghong; Sun, Hongwen

    2016-08-01

    Chlorpyrifos is a widely used organophosphorus pesticide that efficiently protects crops against pests. However, recent studies suggest that severe exposure to chlorpyrifos may present adverse health effects in human. To analyze the exposure level and metabolic characteristics of chlorpyrifos pesticide in urban adults and farmers with/without occupation pesticide contact, the occurrence of urinary chlorpyrifos and methyl chlorpyrifos (CP-me), as well as their metabolite, 3,5,6-trichloro-2-pyridinol (TCPy), was determined in farmers of an agricultural village in China, and in urban adults of a nearby town. The geometric mean (GM) concentrations of TCPy, which is the major marker of chlorpyrifos exposure, were 4.29 and 7.57μg/g-creatinine in urban adults and farmers before pesticide application, respectively. Chlorpyrifos spraying significantly increased the concentrations of urinary TCPy. In the first day after spraying, a GM concentration of 43.7μg/g-creatinine was detected in the urine specimens from farmers, which decreased to 38.1 and 22.8μg/g-creatinine in the second and third day after chlorpyrifos spraying. The ratio of TCPy and its parent compounds, i.e. chlorpyrifos and CP-me, was positively associated with the sum concentration of urinary chlorpyrifos, CP-me, and TCPy, suggesting the increasing metabolic efficiency of chlorpyrifos to TCPy at higher chlorpyrifos exposure levels. To estimate the farmers' occupational exposure to chlorpyrifos pesticide, a new model based on the fitted first-order elimination kinetics of TCPy was established. Occupational chlorpyrifos exposure in a farmer was estimated to be 3.70μg/kg-bw/day (GM), which is an exposure level that is higher than the recommended guideline levels. Significant increase of urinary 8-hydroxydeoxyguanosine (8-OHdG) was observed on the first day after chlorpyrifos spraying, which indicates a potential oxidative damage in farmers. However, urinary 8-OHdG returned to its baseline level within two

  8. Does the Effect of Exposure to TV Sex on Adolescent Sexual Behavior Vary by Genre?

    Science.gov (United States)

    Gottfried, Jeffrey A; Vaala, Sarah E; Bleakley, Amy; Hennessy, Michael; Jordan, Amy

    2013-02-01

    Using the Integrated Model of Behavioral Prediction, this study examines the effects of exposure to sexual content on television by genre, specifically looking at comedy, drama, cartoon, and reality programs, on adolescents' sex-related cognitions and behaviors. Additionally, we compared the amount and explicitness of sexual content as well as the frequency of risk and responsibility messages in these four genres. Findings show that overall exposure to sexual content on television was not related to teens' engagement in sexual intercourse the following year. When examined by genre, exposure to sexual content in comedies was positively associated while exposure to sexual content in dramas was negatively associated with attitudes regarding sex, perceived normative pressure, intentions, and engaging in sex one year later. Implications of adolescent exposure to various types of content and for using genre categories to examine exposure and effects are discussed. PMID:24187395

  9. Effects of microwave exposure on motor learning and GluR2 phosphorylation in rabbit cerebellum

    International Nuclear Information System (INIS)

    Objective: To investigate the effects of microwave exposure on motor learning and Glutamate receptor 2(GluR2) phosphorylation in rat cerebellum. Methods: The rabbits were trained for seven days to form eye-blink conditioning, and then divided randomly into control and microwave exposure group (at hours 0,3,24 and 72 subgroups after exposure, respectively). The rabbits were accepted 90 mW/cm2 microwave exposure for 30 minutes, and the rectal temperature were detected immediately after exposure and specific absorption rate (SAR) value were calculated. Eye-blink conditioning were detected immediately after exposure, and cerebellar GluR2 protein and GluR2 phosphorylation were detected with Western blotting. Results: Rectal temperature of rabbits were increased by 3.02 degree C after exposure, and SAR value was 8.74 W/kg. The eye-blink conditioning decreased significantly after exposure, and cerebellar GluR2 protein expression had no significant alteration but phosphorylation reduced significantly after exposure. Conclusions: 90 mW/cm2 microwave exposure has injurious effects on cerebellar GluR2 phosphorylation and motor learning. (authors)

  10. Cumulative effects of repeated exposure to pO2 = 200 kPa (2 atm).

    Science.gov (United States)

    Shykoff, Barbara E

    2014-01-01

    Even asymptomatic exposures to elevated oxygen partial pressure (pO2) can influence subsequent exposures. Dry chamber dives of three hours' duration at pO2 of 200 kPa were conducted to examine cumulative effects. Experiments were single (n = 27), or paired exposures with surface intervals (SIs) 15 to 17 hours (n = 30), six hours (n = 33), or three hours (n = 36). Flow-volume loops, diffusing capacity, and symptoms were recorded before and after exposures. Immediately after surfacing from second exposures, some significant (p < 0.05) mean changes from baseline in pulmonary function indices occurred for all SIs and persisted for two days for three-hour SIs and for one day for 15-hour SIs. Incidences of symptoms were 15% immediately after one exposure and 28%, 38% and 31% immediately after a second exposure following 15-, six- , or three-hour SIs, respectively. Incidences of changes in pulmonary function indices (deltaPF) were 5%, 11%, 12% and 14% for single exposures or two with 15-, six-, or three-hour SIs, respectively. Two days following the second exposure, resolution of symptoms was incomplete after six- or 15-hour SIs, as was resolution of deltaPF after 15-hour SIs. The incidences indicate non-linear superposition of effects of a first and second exposure, and are not readily explained by delayed-onset injury. PMID:25109082

  11. Commuters’ air pollution exposure and acute health effects

    NARCIS (Netherlands)

    Zuurbier, M.M.M.

    2011-01-01

    People spend a substantial proportion of their time in traffic. In Europe, the average daily time in traffic is one to one and a half hour. Because of high in-traffic exposures and because most of the journeys are made during rush hours, the one to one and a half hour in traffic contributes dispropo

  12. The exposure to and health effects of antimony

    DEFF Research Database (Denmark)

    Cooper, Ross G.; Harrison, Adrian Paul

    2009-01-01

    minireview for selecting articles were adopted from proposed criteria in The International Classification of Functioning, Disability and Health. Articles were classified from an acute and chronic exposure and toxicity thrust. Results: The proportion of utililsed and non-utilised articles was tabulated...

  13. The effect of exposure on MaxRGB color constancy

    Science.gov (United States)

    Funt, Brian; Shi, Lilong

    2010-02-01

    The performance of the MaxRGB illumination-estimation method for color constancy and automatic white balancing has been reported in the literature as being mediocre at best; however, MaxRGB has usually been tested on images of only 8-bits per channel. The question arises as to whether the method itself is inadequate, or rather whether it has simply been tested on data of inadequate dynamic range. To address this question, a database of sets of exposure-bracketed images was created. The image sets include exposures ranging from very underexposed to slightly overexposed. The color of the scene illumination was determined by taking an extra image of the scene containing 4 Gretag Macbeth mini Colorcheckers placed at an angle to one another. MaxRGB was then run on the images of increasing exposure. The results clearly show that its performance drops dramatically when the 14-bit exposure range of the Nikon D700 camera is exceeded, thereby resulting in clipping of high values. For those images exposed such that no clipping occurs, the median error in MaxRGB's estimate of the color of the scene illumination is found to be relatively small.

  14. Effects of exposure to ozone on susceptibility to experimental tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, G.B.; Fenters, J.D.; Ehrlich, R.; Gardner, D.E.

    1981-09-01

    Exposure of mice to 1.96 mg/m3 ozone (O3) 3 h/day, 5 days/week, for up to 8 weeks beginning at 1 or 2 weeks after challenge with Mycobacterium tuberculosis R1Rv resulted in significant enhancement of bacterial titers in the lungs at 5 through 8 weeks after challenge when compared to mice exposed to filtered air. Exposure to lower concentrations of O3 did not produce any significant changes compared to controls. Exposure of guinea pigs to 2.9 mg/m3O3 for 3 h immediately after challenge with M. tuberculosis resulted in a suppression of the cutaneous delayed hypersensitivity response, without affecting the serum hemagglutination antibody titers. However, exposure of guinea pigs to 0.98 mg/m3 O3 3h/day for 5 days, initiated within 3 h after the infectious challenge, enhanced hemagglutination antibody titers initially, but the delayed hypersensitivity reaction did not differ from controls.

  15. Effect of Early Life Exposure to Air Pollution on Development of Childhood Asthma

    OpenAIRE

    Clark, Nina Annika; Demers, Paul A.; Karr, Catherine J.; Koehoorn, Mieke; Lencar, Cornel; Tamburic, Lillian; Brauer, Michael

    2009-01-01

    Background There is increasing recognition of the importance of early environmental exposures in the development of childhood asthma. Outdoor air pollution is a recognized asthma trigger, but it is unclear whether exposure influences incident disease. We investigated the effect of exposure to ambient air pollution in utero and during the first year of life on risk of subsequent asthma diagnosis in a population-based nested case–control study. Methods We assessed all children born in southwest...

  16. Double Dose: High Family Conflict Enhances the Effect of Media Violence Exposure on Adolescents’ Aggression

    OpenAIRE

    Patti M. Valkenburg; Vossen, Helen G.M.; Wouter D Weeda; Jessica Taylor Piotrowski; Karin M. Fikkers

    2013-01-01

    We investigated how exposure to media violence and family conflict affects adolescents’ subsequent aggressive behavior. We expected a double dose effect, meaning that high media violence exposure would lead to higher levels of aggression for adolescents in high conflict families compared to low conflict families. A total of 499 adolescents (aged 10 to 14, 48% girls) participated in a two-wave longitudinal survey (4-month interval). Survey questions assessed their exposure to violence on tel...

  17. Repeated cue exposure effects on subjective and physiological indices of chocolate craving

    OpenAIRE

    Gucht, Dinska Van; Vansteenwegen, Debora; Beckers, Tom; Hermans, Dirk; Baeyens, Frank; Van den Bergh, Omer

    2008-01-01

    The aim of this study is to investigate the effects of repeated unreinforced exposure to chocolate cues in persons reporting chocolate craving. Participants in the experimental group (n=40) received 10 consecutive brief exposures to chocolate cues in each of two sessions, separated by 1-3 days. Control participants (n=18) received two exposures at the start and end of each session. Chocolate craving was measured (alternately) through subjective report and the amount of saliva secretion to cho...

  18. Effects of herbicides on Lemna gibba and recovery from damage after prolonged exposure.

    Science.gov (United States)

    Mohammad, M; Itoh, K; Suyama, K

    2010-04-01

    To determine the potential impact of contaminants on the aquatic vascular plants Lemna sp., toxicity tests are usually conducted for a 4- to 14-day exposure, and the toxicity is usually expressed as EC50. However, the effects of longer exposure and the recovery potential after exposure to chemicals are other important factors which should be considered. We present the relative risks of a variety of exposure scenarios and recovery potentials from damage, using herbicides with different modes of action. Toxicity was assessed on the basis of both EC50 and relative growth rate (RGR) compared with untreated controls in exposure and recovery. The EC50 of atrazine was found to be 89 ppb, and its phytostatic concentrations were 1600 and 800 ppb for exposure periods of 14 and 28 days, respectively, and no phytocidal effects were observed up to 3200 ppb for a 28-day exposure. The RGR in recovery was not affected by the RGR in exposure, and regrowth was possible even after complete inhibition of growth for 28 days at the highest concentration tested. Alachlor, with an EC50 of 31 ppb, was phytostatic at 400 ppb for a 14-day exposure and phytocidal at 200 ppb for 21- and 28-day exposures. Paraquat, with an EC50 of 31 ppb, showed phytocidal rather than phytostatic effects. All phytostatic fronds could not grow in the recovery period, and the phytocidal concentration decreased with exposure period, from 80 ppb for a 7-day exposure to 20 ppb for 21- and 28-day exposures. The RGR of alachlor and paraquat in recovery was dependent on the RGR in exposure. In the case of cyclosulfamuron, phytostatic concentrations were 100 and 50 ppb for 7- and 14-day exposures, respectively. In the case of exposures longer than 21 days, however, it exhibited phytocidal activity at 10 ppb. The results of this study suggest that it is important to examine the effects of chemicals over a longer exposure period as well as the recovery potential from damage for reliable ecological risk assessment. PMID

  19. The effects of electric fields on the immune system of exposed mice

    International Nuclear Information System (INIS)

    Swiss-Webster male mice were exposed for 30 and 60 days in a 60-Hz, 100 kV/meter electric field to determine the effect of exposure on humoral and cellular components of the immune system. Quantitation of serum lgG and lgM with a double-antibody radioimmune assay revealed no significant difference in the levels of these immunoglobulins between exposed and sham-exposed mice for the two time periods. In conjunction with the serum studies, the relative concentrations of T and B lymphocytes in the peripheral blood were measured using the spontaneous rosette assay and the binding of fluorescent-labeled goat anti-mouse immunoglobulins. No significant difference was observed in the distribution of these lymphocyte populations in exposed and sham-exposed mice. (author)

  20. Combined Effects of Prenatal Exposures to Environmental Chemicals on Birth Weight

    Directory of Open Access Journals (Sweden)

    Eva Govarts

    2016-05-01

    Full Text Available Prenatal chemical exposure has been frequently associated with reduced fetal growth by single pollutant regression models although inconsistent results have been obtained. Our study estimated the effects of exposure to single pollutants and mixtures on birth weight in 248 mother-child pairs. Arsenic, copper, lead, manganese and thallium were measured in cord blood, cadmium in maternal blood, methylmercury in maternal hair, and five organochlorines, two perfluorinated compounds and diethylhexyl phthalate metabolites in cord plasma. Daily exposure to particulate matter was modeled and averaged over the duration of gestation. In single pollutant models, arsenic was significantly associated with reduced birth weight. The effect estimate increased when including cadmium, and mono-(2-ethyl-5-carboxypentyl phthalate (MECPP co-exposure. Combining exposures by principal component analysis generated an exposure factor loaded by cadmium and arsenic that was associated with reduced birth weight. MECPP induced gender specific effects. In girls, the effect estimate was doubled with co-exposure of thallium, PFOS, lead, cadmium, manganese, and mercury, while in boys, the mixture of MECPP with cadmium showed the strongest association with birth weight. In conclusion, birth weight was consistently inversely associated with exposure to pollutant mixtures. Chemicals not showing significant associations at single pollutant level contributed to stronger effects when analyzed as mixtures.

  1. Dose-rate effects on lung cancers induced by exposure to radon progeny in rats

    International Nuclear Information System (INIS)

    Epidemiological studies in uranium miners and other underground miners showed an association between an excess risk of lung cancer and exposure to radon and its progeny, but the evidence of an excess risk of lung cancer from residential radon indoor exposure is less certain. Animal studies were used in addition to epidemiological studies to investigate the effects of exposure, exposure rate and other factors in predicting risks resulting from human exposures both in the home and in the workplace. The advantage of animal data is that animal experiments are generally conducted under well controlled conditions and that exposure and exposure rate can be estimated more accurately. Radon animal data, obtained primarily in adult rats, were provided mainly by the Pacific Northwest Laboratory (PNL) in USA and our group in France. Despite the fact that significant cumulative exposures at typical residential exposure rates of about 1.810-5 Jhm-3 per week, approximately 0.005 WLM per week, cannot be tested in a short-lived species like the rat, the rat model is valuable for reducing the uncertainties that exist in human data, particularly in regard to the exposure-rate effect. In PNL lifespan animal experiments, a trend towards increasing tumour risk with decreased exposure rate has been reported in Wistar rats exposed at 2.1 mJm-3 (100 WL) and 21 mJm-3 (1,000 WL) and cumulative exposures varying from 2.3 Jhm-3 (640 WLM) up to 18.4 Jhm-3 (5,120 WLM). A trend towards increasing tumour risk with decreased exposure rate was observed in our Sprague-Dawley rats exposed at cumulative exposure varying from about 0.72 Jhm-3 (200 WLM) up to 10.8 Jhm-3 (3,000 WLM) and high exposure rates varying from 0.09 Jhm-3 (25 WLM per week) to 1.8 Jm-3 (500 WLM per week). In contrast, the results obtained at low cumulative exposure, comparable to domestic indoor exposures showed no evidence of an inverse exposure-rate effect. Chronic radon exposure at 0.09 Jhm-3 (25 WLM), protracted over a 18

  2. Effect of hydrolysis on identifying prenatal cannabis exposure

    OpenAIRE

    Gray, Teresa R.; Barnes, Allan J.; Huestis, Marilyn A.

    2010-01-01

    Identification of prenatal cannabis exposure is important due to potential cognitive and behavioral consequences. A two-dimensional gas chromatography–mass spectrometry method for cannabinol, Δ9-tetrahydrocannabinol (THC), 11-hydroxy-THC (11-OH-THC), 8β,11-dihydroxy-THC, and 11-nor-9-carboxy-THC (THCCOOH) quantification in human meconium was developed and validated. Alkaline, enzymatic, and enzyme–alkaline tandem hydrolysis conditions were optimized with THC- and THCCOOH-glucuronide reference...

  3. Listen, Learn, Like! Dorsolateral Prefrontal Cortex Involved in the Mere Exposure Effect in Music

    Directory of Open Access Journals (Sweden)

    Anders C. Green

    2012-01-01

    Full Text Available We used functional magnetic resonance imaging to investigate the neural basis of the mere exposure effect in music listening, which links previous exposure to liking. Prior to scanning, participants underwent a learning phase, where exposure to melodies was systematically varied. During scanning, participants rated liking for each melody and, later, their recognition of them. Participants showed learning effects, better recognising melodies heard more often. Melodies heard most often were most liked, consistent with the mere exposure effect. We found neural activations as a function of previous exposure in bilateral dorsolateral prefrontal and inferior parietal cortex, probably reflecting retrieval and working memory-related processes. This was despite the fact that the task during scanning was to judge liking, not recognition, thus suggesting that appreciation of music relies strongly on memory processes. Subjective liking per se caused differential activation in the left hemisphere, of the anterior insula, the caudate nucleus, and the putamen.

  4. [The effects of prenatal environmental exposures on children development and health].

    Science.gov (United States)

    Tao, Shuman; Tao, Fangbiao

    2016-02-01

    The negative effects of environmental exposure during pregnancy on fetal growth and children development have been confirmed. It has been found that environmental exposures during pregnancy have a great influence on the growth and development of fetus, birth outcomes and children's psychology, behavior and neural development. In this review, according to different types of environmental exposures, we focused on the key issues of the fetus or children induced by four aspects of environment exposure, including environmental chemicals, unhealthy life styles and behaviors, stress and other risk factors, and discussed the adverse effects of environmental factors on the growth and development of infants, children's psychology, behavior, social and cognitive, such as birth defects, autism spectrum disorders, attention deficit hyperactivity disorder, emotional problems, learning disorder and intelligence development and so on. We also suggested that the researches on mechanism of the negative effects of environmental exposure on children's health should be strengthened in the future. PMID:26926732

  5. Listen, Learn, Like! Dorsolateral Prefrontal Cortex Involved in the Mere Exposure Effect in Music

    Science.gov (United States)

    Green, Anders C.; Bærentsen, Klaus B.; Stødkilde-Jørgensen, Hans; Roepstorff, Andreas; Vuust, Peter

    2012-01-01

    We used functional magnetic resonance imaging to investigate the neural basis of the mere exposure effect in music listening, which links previous exposure to liking. Prior to scanning, participants underwent a learning phase, where exposure to melodies was systematically varied. During scanning, participants rated liking for each melody and, later, their recognition of them. Participants showed learning effects, better recognising melodies heard more often. Melodies heard most often were most liked, consistent with the mere exposure effect. We found neural activations as a function of previous exposure in bilateral dorsolateral prefrontal and inferior parietal cortex, probably reflecting retrieval and working memory-related processes. This was despite the fact that the task during scanning was to judge liking, not recognition, thus suggesting that appreciation of music relies strongly on memory processes. Subjective liking per se caused differential activation in the left hemisphere, of the anterior insula, the caudate nucleus, and the putamen. PMID:22548168

  6. Effectiveness of employee training and motivation programs in reducing exposure to inorganic lead and lead alkyls.

    Science.gov (United States)

    Maples, T W; Jacoby, J A; Johnson, D E; Ter Haar, G L; Buckingham, F M

    1982-09-01

    The Occupational Safety and Health Administration has advanced engineering controls over administrative controls and protective equipment to reduce exposures to chemicals in the workplace. The application of employee training and motivation programs (such as job safety analysis) to reduce exposures to chemicals has not been emphasized. To determine the effectiveness of such programs, a pilot project in an alkyl lead production facility was conducted with 35 employees in an effort to reduce exposures to organic and inorganic lead. Results after 12 months show a 40% reduction in lead-in-urine and a 24% reduction in lead-in-blood, both indicators of total exposure to organic inorganic lead.

  7. Listen, learn, like! Dorsolateral prefrontal cortex involved in the mere exposure effect in music

    DEFF Research Database (Denmark)

    Green, Anders Christian; Bærentsen, Klaus B.; Stødkilde-Jørgensen, Hans;

    2012-01-01

    exposure in bilateral dorsolateral prefrontal and inferior parietal cortex, probably reflecting retrieval and working memory-related processes. This was despite the fact that the task during scanning was to judge liking, not recognition, thus suggesting that appreciation of music relies strongly on memory......We used functional magnetic resonance imaging to investigate the neural basis of the mere exposure effect in music listening, which links previous exposure to liking. Prior to scanning, participants underwent a learning phase, where exposure to melodies was systematically varied. During scanning...

  8. Depression-like effect of prenatal buprenorphine exposure in rats.

    Directory of Open Access Journals (Sweden)

    Chih-Jen Hung

    Full Text Available Studies indicate that perinatal opioid exposure produces a variety of short- and long-term neurobehavioral consequences. However, the precise modes of action are incompletely understood. Buprenorphine, a mixed agonist/antagonist at the opioid receptors, is currently being used in clinical trials for managing pregnant opioid addicts. This study provides evidence of depression-like consequence following prenatal exposure to supra-therapeutic dose of buprenorphine and sheds light on potential mechanisms of action in a rat model involving administration of intraperitoneal injection to pregnant Sprague-Dawley rats starting from gestation day 7 and lasting for 14 days. Results showed that pups at postnatal day 21 but not the dams had worse parameters of depression-like neurobehaviors using a forced swimming test and tail suspension test, independent of gender. Neurobehavioral changes were accompanied by elevation of oxidative stress, reduction of plasma levels of brain-derived neurotrophic factor (BDNF and serotonin, and attenuation of tropomyosin-related kinase receptor type B (TrkB phosphorylation, extracellular signal-regulated kinase (ERK phosphorylation, protein kinase A activity, cAMP response element-binding protein (CREB phosphorylation, and CREB DNA-binding activity. Since BDNF/serotonin and CREB signaling could orchestrate a positive feedback loop, our findings suggest that the induction of oxidative stress, reduction of BDNF and serotonin expression, and attenuation of CREB signaling induced by prenatal exposure to supra-therapeutic dose of buprenorphine provide evidence of potential mechanism for the development of depression-like neurobehavior.

  9. The Effects of Repeated Exposure to Graphic Fear Appeals on Cigarette Packages : A Field Experiment

    NARCIS (Netherlands)

    Dijkstra, Arie; Colin, Bos,

    2015-01-01

    Experimental studies on the effects of graphic fear appeals on cigarette packages typically expose smokers in a single session to a fear appeal, although in practice the exposure is always repeated. The present study applied an improved study design with repeated exposure to fear appeals on cigarett

  10. The Effects of Repeated Exposure to Graphic Fear Appeals on Cigarette Packages: A Field Experiment

    NARCIS (Netherlands)

    Dijkstra, A.; Bos, C.

    2015-01-01

    Experimental studies on the effects of graphic fear appeals on cigarette packages typically expose smokers in a single session to a fear appeal, although in practice the exposure is always repeated. The present study applied an improved study design with repeated exposure to fear appeals on cigarett

  11. Exposure to Sexist Humor and Rape Proclivity: The Moderator Effect of Aversiveness Ratings

    Science.gov (United States)

    Romero-Sanchez, Monica; Duran, Mercedes; Carretero-Dios, Hugo; Megias, Jesus L.; Moya, Miguel

    2010-01-01

    The aim of this study is to explore the effect of exposure to sexist humor about women on men's self-reported rape proclivity. Earlier studies have shown that exposure to this type of humor increases rape proclivity and that funniness responses to jokes are a key element to consider. However, the role of aversiveness responses has not been…

  12. Fear of blushing : Effects of task concentration training versus exposure in vivo on fear and physiology

    NARCIS (Netherlands)

    Mulkens, S; Bogels, SM; de Jong, Peter; Louwers, J

    2001-01-01

    Patients with fear of blushing as the predominant complaint (N = 31) were randomly assigned to (1) exposure in vivo (EXP), or (2) task concentration training (TCT), in order to test the effect of redirecting attention above exposure only. In addition, it was investigated whether treatment reduced ac

  13. Effects of prenatal exposure to chronic mild stress and toluene in rats

    DEFF Research Database (Denmark)

    Hougaard, K. S.; Andersen, Maud Bering; Hansen, A. M.;

    2005-01-01

    . The corticosterone response to restraint seemed modified by prenatal exposure to toluene. Lactational body weight was decreased in offsprings subjected to CMS, primarily due to effects in the combined exposure group. Cognitive function was investigated in the Morris water maze, and some indications of improved...

  14. Double dose: High family conflict enhances the effect of media violence exposure on adolescents’ aggression

    NARCIS (Netherlands)

    K.M. Fikkers; J. Piotrowski; W.D. Weeda; H.G.M. Vossen; P.M. Valkenburg

    2013-01-01

    We investigated how exposure to media violence and family conflict affects adolescents’ subsequent aggressive behavior. We expected a double dose effect, meaning that high media violence exposure would lead to higher levels of aggression for adolescents in high conflict families compared to low conf

  15. Repeated cue exposure effects on subjective and physiological indices of chocolate craving

    NARCIS (Netherlands)

    D. van Gucht; D. Vansteenwegen; T. Beckers; D. Hermans; F. Baeyens; O. Van den Bergh

    2008-01-01

    The aim of this study is to investigate the effects of repeated unreinforced exposure to chocolate cues in persons reporting chocolate craving. Participants in the experimental group (n ¼ 40) received 10 consecutive brief exposures to chocolate cues in each of two sessions, separated by 1-3 days. Co

  16. Effect of glucagon-like peptide-2 exposure on bone resorption

    DEFF Research Database (Denmark)

    Askov-Hansen, Carsten; Jeppesen, Palle B; Lund, Pernille;

    2013-01-01

    exposure and decreases in CTX in order to determine whether high concentrations or prolonged exposure was the most effective mode of administration. High GLP-2 concentrations resulted from iv bolus injections, whereas a more protracted stimulation was obtained by subcutaneous injections and the addition...

  17. Effects of long-term exposure to air pollution on natural-cause mortality

    DEFF Research Database (Denmark)

    Beelen, Rob; Raaschou-Nielsen, Ole; Stafoggia, Massimo;

    2013-01-01

    Few studies on long-term exposure to air pollution and mortality have been reported from Europe. Within the multicentre European Study of Cohorts for Air Pollution Effects (ESCAPE), we aimed to investigate the association between natural-cause mortality and long-term exposure to several air...... pollutants....

  18. Evaluating the Effect of Educational Media Exposure on Aggression in Early Childhood

    Science.gov (United States)

    Ostrov, Jamie M.; Gentile, Douglas A.; Mullins, Adam D.

    2013-01-01

    Preschool-aged children (M = 42.44 months-old, SD = 8.02) participated in a short-term longitudinal study investigating the effect of educational media exposure on social development (i.e., aggression and prosocial behavior) using multiple informants and methods. As predicted, educational media exposure significantly predicted increases in both…

  19. Effects of prior exposure to office noise and music on aspects of working memory

    Directory of Open Access Journals (Sweden)

    Andrew Smith

    2010-01-01

    Full Text Available Previous research has suggested that prior exposure to noise reduces the effect of subsequent exposure due to habituation. Similarly, a number of studies have shown that exposure to Mozart′s music leads to better subsequent spatial reasoning performance. Two studies were conducted to extend these findings. The first one examined whether habituation occurs to office noise (including speech and, if so, how long it takes to develop. Thirty-six young adults participated in the first study which compared effects of office noise with quiet on the performance of a maths task. The study also examined the effects of prior exposure to the office noise on the subsequent effect of the noise. The results showed that performance was initially impaired by the office noise but that the effects of the noise were removed by 10 minutes of exposure between tasks. The second experiment attempted to replicate the "Mozart effect" which represents an improvement in spatial reasoning following listening to Mozart. The study also examined whether the Mozart effect could be explained by changes in mood. Twenty-four young adults participated in the study. The results replicated the Mozart effect and showed that it was not due to changes in mood. Overall, these results show that prior exposure to noise or music can influence aspects of working memory. Such effects need to be incorporated into models of effects of noise on cognition and attempts have to be made to eliminate alternative explanations rather than just describing changes that occur in specific contexts.

  20. Effects of prior exposure to office noise and music on aspects of working memory.

    Science.gov (United States)

    Smith, Andrew; Waters, Beth; Jones, Hywel

    2010-01-01

    Previous research has suggested that prior exposure to noise reduces the effect of subsequent exposure due to habituation. Similarly, a number of studies have shown that exposure to Mozart's music leads to better subsequent spatial reasoning performance. Two studies were conducted to extend these findings. The first one examined whether habituation occurs to office noise (including speech) and, if so, how long it takes to develop. Thirty-six young adults participated in the first study which compared effects of office noise with quiet on the performance of a maths task. The study also examined the effects of prior exposure to the office noise on the subsequent effect of the noise. The results showed that performance was initially impaired by the office noise but that the effects of the noise were removed by 10 minutes of exposure between tasks. The second experiment attempted to replicate the "Mozart effect" which represents an improvement in spatial reasoning following listening to Mozart. The study also examined whether the Mozart effect could be explained by changes in mood. Twenty-four young adults participated in the study. The results replicated the Mozart effect and showed that it was not due to changes in mood. Overall, these results show that prior exposure to noise or music can influence aspects of working memory. Such effects need to be incorporated into models of effects of noise on cognition and attempts have to be made to eliminate alternative explanations rather than just describing changes that occur in specific contexts.

  1. Systematic Review of the Exposure Assessment and Epidemiology of High-Frequency Voltage Transients

    Directory of Open Access Journals (Sweden)

    Frank eDe Vocht

    2016-03-01

    Full Text Available Conclusions of epidemiological studies describing adverse health effects as a result of exposure to electromagnetic fields are not unanimous and often contradictory. It has been proposed that an explanation could be that high frequency voltage transients (dirty electricity [DE] which are superimposed on 50/60Hz fields, but are generally not measured, is the real causal agent. DE has been linked to many different health and wellbeing effects, and on the basis of this an industry selling measurement and filtering equipment is growing. We reviewed the available peer-reviewed evidence for DE as a causal agent for adverse human health effects.A literature search was performed in the Cochrane Library, PubMed, Web of Science, Google Scholar and additional publications were obtained from reference lists and from the grey literature. This search resulted in 25 publications; 16 included primary epidemiological and/or exposure data. All studies were reviewed by both authors independently, and including a re-review of studies included in a review of data available up to July 31 2009 by one of the authors. DE has been measured differently in different studies and comparison data are not available. There is no evidence for 50 Graham/Stetzer (G/S units as a safety threshold being anything more than arbitrary. The epidemiological evidence on human health effects of DE is primarily based on, often re-used, case descriptions. Quantitative evidence relies on self-reporting in non-blinded interventions, ecological associations, and one cross-sectional cohort study of cancer risk which does not point to DE as the causal agent. The available evidence for DE as an exposure affecting human health at present does not stand up to scientific scrutiny.

  2. Effects of exposure to idealized body portrayals in an ethnically diverse sample of men and women

    OpenAIRE

    Skorek, Malgorzata

    2011-01-01

    There is considerable support in the literature for the proposition that exposure to portrayals of idealized bodies in advertising has various negative effects on men’s and women’s self and body image. Yet, there is also evidence for self-enhancement effects of these advertisements. This disparity in findings suggests the possibility that not all men and women react to advertising portrayals in the same way and invites a careful study of potential moderators of exposure effects...

  3. Investigations into the Effects of Long-Term Seawater Exposure on Graphite/Epoxy Composite Materials

    OpenAIRE

    Sloan, Forrest E.

    1991-01-01

    The investigations documented here were intended to determine whether graphite-fiber-reinforced plastics can survive the highly aggressive seawater environment when used as structural materials in advanced ocean engineering designs. Two general effects of seawater exposure were identified as potentially life-limiting phenomena. The first effect is a weakening of the fiber-to-matrix bond caused by exposure of the interface to moisture. The second effect is the establishment of an electrolyte (...

  4. Effects of exposure to oil spills on human health: Updated review.

    Science.gov (United States)

    Laffon, Blanca; Pásaro, Eduardo; Valdiglesias, Vanessa

    2016-01-01

    Oil spills may involve health risks for people participating in the cleanup operations and coastal inhabitants, given the toxicological properties of the oil components. In spite of this, only after a few major oil spills (crude oil or fuel oil no. 6) have studies on effects of exposure to diverse aspects of human health been performed. Previously, Aguilera et al. (2010) examined all documents published to that date dealing with any type of human health outcome in populations exposed to oil spills. The aim of the present review was to compile all new information available and determine whether evidence reported supports the existence of an association between exposure and adverse human health risks. Studies were classified in three groups according to type of health outcome addressed: (i) effects on mental health, (ii) physical/physiological effects, and (iii) genotoxic, immunotoxic, and endocrine toxicity. New studies published on oil-spill-exposed populations-coastal residents in the vicinity of the spills or participants in cleanup operations-provide additional support to previous evidence on adverse health effects related to exposure regarding different parameters in all three categories considered. Some of the observed effects even indicated that several symptoms may persist for some years after exposure. Hence, (1) health protection in these individuals should be a matter of concern; and (2) health risk assessment needs to be carried out not only at the time of exposure but also for prolong periods following exposure, to enable early detection of any potential exposure-related harmful effects. PMID:27221976

  5. Effects of exposure to oil spills on human health: Updated review.

    Science.gov (United States)

    Laffon, Blanca; Pásaro, Eduardo; Valdiglesias, Vanessa

    2016-01-01

    Oil spills may involve health risks for people participating in the cleanup operations and coastal inhabitants, given the toxicological properties of the oil components. In spite of this, only after a few major oil spills (crude oil or fuel oil no. 6) have studies on effects of exposure to diverse aspects of human health been performed. Previously, Aguilera et al. (2010) examined all documents published to that date dealing with any type of human health outcome in populations exposed to oil spills. The aim of the present review was to compile all new information available and determine whether evidence reported supports the existence of an association between exposure and adverse human health risks. Studies were classified in three groups according to type of health outcome addressed: (i) effects on mental health, (ii) physical/physiological effects, and (iii) genotoxic, immunotoxic, and endocrine toxicity. New studies published on oil-spill-exposed populations-coastal residents in the vicinity of the spills or participants in cleanup operations-provide additional support to previous evidence on adverse health effects related to exposure regarding different parameters in all three categories considered. Some of the observed effects even indicated that several symptoms may persist for some years after exposure. Hence, (1) health protection in these individuals should be a matter of concern; and (2) health risk assessment needs to be carried out not only at the time of exposure but also for prolong periods following exposure, to enable early detection of any potential exposure-related harmful effects.

  6. EFFECTS OF TRITIUM GAS EXPOSURE ON ELECTRICALLY CONDUCTING POLYMERS

    Energy Technology Data Exchange (ETDEWEB)

    Kane, M.; Clark, E.; Lascola, R.

    2009-12-16

    state of the main backbone chain, or by protonation of the imine groups [de Acevedo, 1999]. There are several types of radiation sensors commercially available, including ionization chambers, geiger counters, proportional counters, scintillators and solid state detectors. Each type has advantages, although many of these sensors require expensive electronics for signal amplification, are large and bulky, have limited battery life or require expensive materials for fabrication. A radiation sensor constructed of a polymeric material could be flexible, light, and the geometry designed to suit the application. Very simple and inexpensive electronics would be necessary to measure the change in conductivity with exposure to radiation and provide an alarm system when a set change of conductivity occurs in the sensor that corresponds to a predetermined radiation dose having been absorbed by the polymer. The advantages of using a polymeric sensor of this type rather than those currently in use are the flexibility of sensor geometry and relatively low cost. It is anticipated that these sensors can be made small enough for glovebox applications or have the ability to monitor the air tritium levels in places where a traditional monitor cannot be placed. There have been a few studies on the changes in conductivity of polyaniline specifically for radiation detection [de Acevedo, 1999; Lima Pacheco, 2003], but there have been no reports on the effects of tritium (beta radiation) on conducting polymers, such as polyaniline or polythiophene. The direct implementation of conducting polymers as radiation sensor materials has not yet been commercialized due to differing responses with total dose, dose rate, etc. Some have reported a large increase in the surface conductivity with radiation dose while others report a marked decrease in conductive properties; these differing observations may reflect the competing mechanisms of chain scission and cross-linking. However, it is clear that the

  7. Evaluation of spermatogenesis and fertility in F1 male rats after in utero and neonatal exposure to extremely low frequency electromagnetic fields

    Institute of Scientific and Technical Information of China (English)

    M. K. Chung; S. J. Lee; Y. B. Kim; S. C. Park; D. H. Shin; S. H. Kim; J. C. Kim

    2005-01-01

    Aim: To determine whether in utero and neonatal exposure to a 60 Hz extremely low frequency electromagnetic field (EMF) results in spermatotoxicity and reproductive dysfunction in the F1 offspring of rats. Methods: Age-matched,pregnant Sprague-Dawley rats were exposed continuously (21 h/day) to a 60 Hz EMF at field strengths of 0 (sham control), 5, 83.3 or 500 μT from day 6 of gestation through to day 21 of lactation. The experimentally generated magnetic field was monitored continuously (uninterrupted monitoring over the period of the study) throughout the study. Results: No exposure-related changes were found in exposed or sham-exposed animals with respect to the anogenital distance, preputial separation, testis weight, testicular histology, sperm count, daily sperm production,sperm motility, sperm morphology and reproductive capacity of F1 offspring. Conclusion: Exposure of SpragueDawley rats to a 60 Hz EMF at field strengths of up to 500 μT from day 6 of gestation to day 21 of lactation did not produce any detectable alterations in offspring spermatogenesis and fertility.

  8. Over-exposure effects on the distortion product otoacoustic emission

    DEFF Research Database (Denmark)

    Reuter, Karen

    with hearing-loss. Reported measurements of OAEs before and after noise exposure suggest that OAE is a more sensitive measure for the hearing function than pure-tone audiometry and therefore might be a measure for the early identification of hearing loss. No individual diagnosis of OAEs is possible today......, however. In the present study it was investigated, whether Distortion Product OtoAcoustic Emission (DPOAE) parameters exist, which indicate the early stage of a hearing loss. DPOAE was obtained with high frequency resolution, and its characteristic spectral fine structure was analyzed. Data of subjects...

  9. Oil exposure and effects in subtidal fish following the Exxon Valdez oil spill

    International Nuclear Information System (INIS)

    The assessment of oil exposure and resulting biological effects in subtidal fish following marine oil spills is a rather challenging task, due to difficulty in sampling and a lack of methodologies that allow direct determination of petroleum exposure. Because fish can rapidly metabolize petroleum hydrocarbons, standard chemical analyses are of little use for assessing exposure of fish to oil. However, methods are now available for measuring the metabolites of petroleum hydrocarbons in fish, as described elsewhere by Krahn and her colleagues. There have also been advances in determining early biochemical effects-such as induction of the cytochrome P450 system-and more severe biological effects-such as histopathological alterations and reproductive disfunction-in fish species following exposure to petroleum hydrocarbons and related compounds. Accordingly, following the Exxon Valdez oil spill, the authors have been using these approaches and methodologies to measure oil exposure in subtidal fish species, together with associated biological effects. These studies have been conducted at sites inside Prince William Sound and along the Kenai and Alaska Peninsulas. Our results show a continuing exposure of several fish species, including benthic species, which indicates petroleum contamination of subtidal areas. The authors have also assessed reproductive function and histopathological alterations in several of these species; and while major effects have not been documented, some suggestion of histopathological alterations of gill exists in one species of benthic fish. Still to be determined are the potential impacts on fishery resources of long-term exposure to petroleum, albeit at moderate to low levels

  10. Aerosolized Red Tide Toxins (Brevetoxins) and Asthma: Continued health effects after 1 hour beach exposure.

    Science.gov (United States)

    Kirkpatrick, Barbara; Fleming, Lora E; Bean, Judy A; Nierenberg, Kate; Backer, Lorraine C; Cheng, Yung Sung; Pierce, Richard; Reich, Andrew; Naar, Jerome; Wanner, Adam; Abraham, William M; Zhou, Yue; Hollenbeck, Julie; Baden, Daniel G

    2011-01-01

    Blooms of the toxic dinoflagellate, Karenia brevis, produce potent neurotoxins in marine aerosols. Recent studies have demonstrated acute changes in both symptoms and pulmonary function in asthmatics after only 1 hour of beach exposure to these aerosols. This study investigated if there were latent and/or sustained effects in asthmatics in the days following the initial beach exposure during periods with and without an active Florida red tide.Symptom data and spirometry data were collected before and after 1 hour of beach exposure. Subjects kept daily symptom diaries and measured their peak flow each morning for 5 days following beach exposure. During non-exposure periods, there were no significant changes in symptoms or pulmonary function either acutely or over 5 days of follow-up. After the beach exposure during an active Florida red tide, subjects had elevated mean symptoms which did not return to the pre-exposure baseline for at least 4 days. The peak flow measurements decreased after the initial beach exposure, decreased further within 24 hours, and continued to be suppressed even after 5 days. Asthmatics may continue to have increased symptoms and delayed respiratory function suppression for several days after 1 hour of exposure to the Florida red tide toxin aerosols. PMID:21499552

  11. Effects of Prenatal Alcohol Exposure on the Developing Kidneys

    Directory of Open Access Journals (Sweden)

    Farahnak Assadi

    2008-04-01

    Full Text Available Objective: Clinical and experimental studies strongly suggest that prenatal alcohol exposure is associated with zinc deficiency and impaired renal tubular function. Whether maternal alcohol consumption during pregnancy causes renal tubular cell injury is unknown.Material & Methods: Renal function was studied in 8 infants with fetal alcohol syndrome (FAS and 8 healthy age-matched infants. Renal function and structure were also examined in 11 offspring of rats exposed to alcohol during gestation.Findings: Infants with FAS had limited ability to concentrate urine after water restriction (P<0.001 and impaired acidification after acute acid loading (P<0.001 compared to control group. Plasma zinc levels were lower (P<0.001 and urinary zinc excretion was higher (P<0.001 in infants with FAS compared to control infants. Scanning electron microscopic studies revealed cytoplasmic mitochondrial hypertrophy and vacuolar structures of the epithelial cells of the cortical collecting ducts in the rat kidney following fetal exposure to alcohol.Conclusion: These findings suggest that offspring of rats exposed to alcohol during fetal life have renal functional and structural abnormalities that may be responsible in the genesis of renal functional abnormalities as described in infants with FAS.

  12. Biomarkers for assessing potential carcinogenic effects of chronic arsenic exposure in Inner Mongolia, CHINA

    Science.gov (United States)

    Arsenic is ubiquitous in the environment. Chronic arsenic exposure via drinking water has been associated. with carcinogenic, cardiovascular, neurological and diabetic effects in humans and has been of great public health concern worldwide. In 2001, U.S. Environmental Protection ...

  13. Transgenerational Effects of Stress Exposure on Offspring Phenotypes in Apomictic Dandelion

    NARCIS (Netherlands)

    Verhoeven, K.J.F.; Gurp, van T.P.

    2012-01-01

    Heritable epigenetic modulation of gene expression is a candidate mechanism to explain parental environmental effects on offspring phenotypes, but current evidence for environment-induced epigenetic changes that persist in offspring generations is scarce. In apomictic dandelions, exposure to various

  14. Transgenerational effects of stress exposure on offspring phenotypes in apomictic dandelion

    NARCIS (Netherlands)

    Verhoeven, K.J.F.; Van Gurp, T.P.

    2012-01-01

    Heritable epigenetic modulation of gene expression is a candidate mechanism to explain parental environmental effects on offspring phenotypes, but current evidence for environment-induced epigenetic changes that persist in offspring generations is scarce. In apomictic dandelions, exposure to various

  15. PREPUBERTAL EXPOSURES TO COMPOUNDS THAT INCREASE PROLACTIN SECRETION IN THE MALE RAT: EFFECTS ON ADULT PROSTATE

    Science.gov (United States)

    Prepubertal exposure to compounds that increase prolactin secretion in the male rat: effects on the adult prostate.Stoker TE, Robinette CL, Britt BH, Laws SC, Cooper RL.Endocrinology Branch, Reproductive Toxicology Division, National Health and Environmental Effec...

  16. Exposure to aerosols during high-pressure cleaning and relationship with health effects.

    Science.gov (United States)

    Madsen, Anne Mette; Matthiesen, Christoffer B

    2013-01-01

    In different occupations cleaning has been identified as the work task causing the highest exposure to aerosol components. High pressure cleaning (hpc) is a cleaning method used in many environments and seems to be considered as a cleaning method causing high exposure. In the presented study, the literature concerning exposure to aerosols during hpc is reviewed. Only a few studies have been published about exposure to aerosols during hpc. Exposure during hpc has been measured on farms, at waste water treatment plants, at a chemical factory and for graffiti removers. High exposures to bacterial endotoxin or chemical components were found in these environments during hpc. Few cases have been published documenting acute health effects caused by exposure to microorganisms and endotoxin during hpc. High pressure cleaners are also used in private settings but no papers have been found about exposure or related health effects during work in private settings. The use of clean water during hpc is important since effluent water or roof-collected rain water can cause a higher exposure to bioaerosols and related health effects. However, tap water in some areas also seems to have a high content of endotoxin, and this too should be considered when deliberating the protection of the airways of workers. Different attempts have been made to reduce workers' exposure and the health effects of exposure during hpc, among them the use of respiratory protection, ventilation and automation of work processes have been used with some degree of success. However, some of these studies only show tendencies. A high number of repeats seem to be necessary in order to obtain conclusive results. The material to be cleaned, as well as the degree of dirtiness, highly influences the exposure level; therefore, in comparative studies it is important also to consider these parameters. No study has been found which compares exposure during the use of different high pressure cleaners. The comparison of

  17. Chronic and acute effects of coal tar pitch exposure and cardiopulmonary mortality among aluminum smelter workers.

    Science.gov (United States)

    Friesen, Melissa C; Demers, Paul A; Spinelli, John J; Eisen, Ellen A; Lorenzi, Maria F; Le, Nhu D

    2010-10-01

    Air pollution causes several adverse cardiovascular and respiratory effects. In occupational studies, where levels of particulate matter and polycyclic aromatic hydrocarbons (PAHs) are higher, the evidence is inconsistent. The effects of acute and chronic PAH exposure on cardiopulmonary mortality were examined within a Kitimat, Canada, aluminum smelter cohort (n = 7,026) linked to a national mortality database (1957-1999). No standardized mortality ratio was significantly elevated compared with the province's population. Smoking-adjusted internal comparisons were conducted using Cox regression for male subjects (n = 6,423). Ischemic heart disease (IHD) mortality (n = 281) was associated with cumulative benzo[a]pyrene (B(a)P) exposure (hazard ratio = 1.62, 95% confidence interval: 1.06, 2.46) in the highest category. A monotonic but nonsignificant trend was observed with chronic B(a)P exposure and acute myocardial infarction (n = 184). When follow-up was restricted to active employment, the hazard ratio for IHD was 2.39 (95% confidence interval: 0.95, 6.05) in the highest cumulative B(a)P category. The stronger associations observed during employment suggest that risk may not persist after exposure cessation. No associations with recent or current exposure were observed. IHD was associated with chronic (but not current) PAH exposure in a high-exposure occupational setting. Given the widespread workplace exposure to PAHs and heart disease's high prevalence, even modest associations produce a high burden.

  18. Developmental Effects of Exposures to Environmental Factors: The Polish Mother and Child Cohort Study

    Directory of Open Access Journals (Sweden)

    Kinga Polanska

    2013-01-01

    Full Text Available This paper estimates the effects of exposure to environmental factors, including lead, mercury, environmental tobacco smoke (ETS, and polycyclic aromatic hydrocarbons (PAH, on child psychomotor development. The study population consists of mother-child pairs in the Polish Mother and Child Cohort Study. Prenatal and postnatal exposure to environmental factors was determined from biomarker measurements as follows: for lead exposure—cord blood lead level, for mercury—maternal hair mercury level, for ETS—cotinine level in saliva and urine, and for PAH—1-hydroxypyrene (1-HP in urine. At the age of 12 (406 subjects and 24 months (198 subjects children were assessed using Bayley Scales of Infant and Toddler Development. There were no statistically significant effects of prenatal exposure to mercury or 1-HP on child psychomotor development. After adjusting for potential confounders, adverse effects of prenatal exposure to ETS on motor development (β = −2.6; P=0.02 and postnatal exposure to ETS on cognitive (β = −0.2; P=0.05 and motor functions (β = −0.5; P=0.01 were found. The adverse effect of prenatal lead exposure on cognitive score was of borderline significance (β = −6.2; P=0.06. The study underscores the importance of policies and public health interventions that aim to reduce prenatal and postnatal exposure to lead and ETS.

  19. Effects of prenatal cocaine exposure on dopamine system development: a meta-analysis.

    Science.gov (United States)

    Glatt, S J; Bolaños, C A; Trksak, G H; Jackson, D

    2000-01-01

    Several studies have investigated the effects of prenatal cocaine (PCOC) exposure on the nigrostriatal dopaminergic system in animal models of maternal drug abuse, yet independent examinations of striatal dopamine (DA) receptors and tissue DA levels have produced equivocal results. The current meta-analysis provides a quantitative review of the literature on these topics, and analyzes potential moderators of the effects of PCOC exposure on these variables. The results indicate that the effects of PCOC exposure on striatal DA levels, D1 and D2 receptor-binding densities, and D2 receptor-binding affinity are negligible when collapsed over age, sex, species, and several other methodological variables. However, effects of PCOC exposure on some dopaminergic measures were significantly influenced by factors such as age and sex. As expected, and as suggested by the selectivity and specificity of PCOC-induced changes reported in the published literature, the direction and magnitude of differences between genders or age groups in this study were not systematic across all dependent measures. Generally, PCOC exposure was more often linked to decreases, rather than increases, in the selected dependent measures. These findings indicate that PCOC exposure produces selective alterations in striatal dopaminergic system function which do not appear under all experimental circumstances, but which may be important factors in behavioral alterations seen in selected groups after PCOC exposure. PMID:11106856

  20. Chronic escalating cocaine exposure, abstinence/withdrawal, and chronic re-exposure: effects on striatal dopamine and opioid systems in C57BL/6J mice.

    Science.gov (United States)

    Zhang, Yong; Schlussman, Stefan D; Rabkin, Jacqui; Butelman, Eduardo R; Ho, Ann; Kreek, Mary Jeanne

    2013-04-01

    Cocaine addiction is a chronic relapsing disease with periods of chronic escalating self-exposure, separated by periods of abstinence/withdrawal of varying duration. Few studies compare such cycles in preclinical models. This study models an "addiction-like cycle" in mice to determine neurochemical/molecular alterations that underlie the chronic, relapsing nature of this disease. Groups of male C57BL/6J mice received acute cocaine exposure (14-day saline/14-day withdrawal/13-day saline + 1-day cocaine), chronic cocaine exposure (14 day cocaine) or chronic re-exposure (14-day cocaine/14-day withdrawal/14-day cocaine). Escalating-dose binge cocaine (15-30 mg/kg/injection × 3/day, i.p. at hourly intervals) or saline (14-day saline) was administered, modeling initial exposure. In "re-exposure" groups, after a 14-day injection-free period (modeling abstinence/withdrawal), mice that had received cocaine were re-injected with 14-day escalating-dose binge cocaine, whereas controls received saline. Microdialysis was conducted on the 14th day of exposure or re-exposure to determine striatal dopamine content. Messenger RNA levels of preprodynorphin (Pdyn), dopamine D1 (Drd1) and D2 (Drd2) in the caudate putamen were determined by real-time PCR. Basal striatal dopamine levels were lower in mice after 14-day escalating exposure or re-exposure than in those in the acute cocaine group and controls. Pdyn mRNA levels were higher in the cocaine groups than in controls. Long-term adaptation was observed across the stages of this addiction-like cycle, in that the effects of cocaine on dopamine levels were increased after re-exposure compared to exposure. Changes in striatal dopaminergic responses across chronic escalating cocaine exposure and re-exposure are a central feature of the neurobiology of relapsing addictive states. PMID:23164614

  1. Effects of Neonatal Antiepileptic Drug Exposure on Cognitive, Emotional, and Motor Function in Adult Rats

    OpenAIRE

    Patrick A Forcelli; Kozlowski, Ryan; Snyder, Charles; Kondratyev, Alexei; Gale, Karen

    2012-01-01

    Despite the potent proapoptotic effect of several antiepileptic drugs (AEDs) in developmental rodent models, little is known about the long-term impact of exposure during brain development. Clinically, this is of growing concern. To determine the behavioral consequences of such exposure, we examined phenobarbital, phenytoin, and lamotrigine for their effects on adult behaviors after administration to neonatal rats throughout the second postnatal week. AED treatment from postnatal days 7 to 13...

  2. Implicit Structured Sequence Learning: An FMRI Study of the Structural Mere-Exposure Effect

    OpenAIRE

    Karl MagnusPetersson

    2014-01-01

    In this event-related FMRI study we investigated the effect of five days of implicit acquisition on preference classification by means of an artificial grammar learning (AGL) paradigm based on the structural mere-exposure effect and preference classification using a simple right-linear unification grammar. This allowed us to investigate implicit AGL in a proper learning design by including baseline measurements prior to grammar exposure. After 5 days of implicit acquisition, the FMRI results ...

  3. Implicit structured sequence learning: an fMRI study of the structural mere-exposure effect

    OpenAIRE

    Folia, Vasiliki; Petersson, Karl Magnus

    2014-01-01

    In this event-related FMRI study we investigated the effect of five days of implicit acquisition on preference classification by means of an artificial grammar learning (AGL) paradigm based on the structural mere-exposure effect and preference classification using a simple right-linear unification grammar. This allowed us to investigate implicit AGL in a proper learning design by including baseline measurements prior to grammar exposure. After 5 days of implicit acquisition, the FMRI results ...

  4. Extinction-based Processes for Enhancing the Effectiveness of Exposure Therapy

    OpenAIRE

    Culver, Najwa

    2013-01-01

    The dissertation is a three-paper investigation of potential methods for improving exposure therapy outcomes for anxiety disorders. If proven effective, these methods can be utilized to modify exposure therapy for anxiety disorders in order to enhance treatment effects and reduce relapse rates. Study 1 tested a prediction of the Rescorla-Wagner model: that presenting two fear-provoking stimuli simultaneously (compound extinction) would maximize learning during extinction. Participants w...

  5. Evidence for effects of chronic lead exposure on blood pressure in experimental animals: an overview.

    OpenAIRE

    Victery, W

    1988-01-01

    Information obtained in a number of experimental studies conducted over the last 40 years on the effects of lead on blood pressure is reviewed. Differences in animal species, age at beginning of exposure, level of lead exposure, indices of lead burden, and blood pressure effects of each study are reported. In several of the high-dose experiments, hypertension was observed, but nephrotoxicity of lead may have contributed to its development. Moreover, in other high-dose experiments, no hyperten...

  6. Motoneuron axon pathfinding errors in zebrafish: Differential effects related to concentration and timing of nicotine exposure

    Energy Technology Data Exchange (ETDEWEB)

    Menelaou, Evdokia; Paul, Latoya T. [Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 (United States); Perera, Surangi N. [Joseph J. Zilber School of Public Health, University of Wisconsin — Milwaukee, Milwaukee, WI 53205 (United States); Svoboda, Kurt R., E-mail: svobodak@uwm.edu [Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 (United States); Joseph J. Zilber School of Public Health, University of Wisconsin — Milwaukee, Milwaukee, WI 53205 (United States)

    2015-04-01

    Nicotine exposure during embryonic stages of development can affect many neurodevelopmental processes. In the developing zebrafish, exposure to nicotine was reported to cause axonal pathfinding errors in the later born secondary motoneurons (SMNs). These alterations in SMN axon morphology coincided with muscle degeneration at high nicotine concentrations (15–30 μM). Previous work showed that the paralytic mutant zebrafish known as sofa potato exhibited nicotine-induced effects onto SMN axons at these high concentrations but in the absence of any muscle deficits, indicating that pathfinding errors could occur independent of muscle effects. In this study, we used varying concentrations of nicotine at different developmental windows of exposure to specifically isolate its effects onto subpopulations of motoneuron axons. We found that nicotine exposure can affect SMN axon morphology in a dose-dependent manner. At low concentrations of nicotine, SMN axons exhibited pathfinding errors, in the absence of any nicotine-induced muscle abnormalities. Moreover, the nicotine exposure paradigms used affected the 3 subpopulations of SMN axons differently, but the dorsal projecting SMN axons were primarily affected. We then identified morphologically distinct pathfinding errors that best described the nicotine-induced effects on dorsal projecting SMN axons. To test whether SMN pathfinding was potentially influenced by alterations in the early born primary motoneuron (PMN), we performed dual labeling studies, where both PMN and SMN axons were simultaneously labeled with antibodies. We show that only a subset of the SMN axon pathfinding errors coincided with abnormal PMN axonal targeting in nicotine-exposed zebrafish. We conclude that nicotine exposure can exert differential effects depending on the levels of nicotine and developmental exposure window. - Highlights: • Embryonic nicotine exposure can specifically affect secondary motoneuron axons in a dose-dependent manner.

  7. Effects of Ethanol Exposure during Distinct Periods of Brain Development on Hippocampal Synaptic Plasticity

    Directory of Open Access Journals (Sweden)

    Brian R. Christie

    2013-07-01

    Full Text Available Fetal alcohol spectrum disorders occur when a mother drinks during pregnancy and can greatly influence synaptic plasticity and cognition in the offspring. In this study we determined whether there are periods during brain development that are more susceptible to the effects of ethanol exposure on hippocampal synaptic plasticity. In particular, we evaluated how the ability to elicit long-term potentiation (LTP in the hippocampal dentate gyrus (DG was affected in young adult rats that were exposed to ethanol during either the 1st, 2nd, or 3rd trimester equivalent. As expected, the effects of ethanol on young adult DG LTP were less severe when exposure was limited to a particular trimester equivalent when compared to exposure throughout gestation. In males, ethanol exposure during the 1st, 2nd or 3rd trimester equivalent did not significantly reduce LTP in the DG. In females, ethanol exposure during either the 1st or 2nd trimester equivalents did not impact LTP in early adulthood, but following exposure during the 3rd trimester equivalent alone, LTP was significantly increased in the female DG. These results further exemplify the disparate effects between the ability to elicit LTP in the male and female brain following perinatal ethanol exposure (PNEE.

  8. Effects of fetal microwave radiation exposure on offspring behavior in mice

    International Nuclear Information System (INIS)

    The recent rapid development of electronic communication techniques is resulting in a marked increase in exposure of humans to electromagnetic fields (EMFs). This has raised public concerns about the health hazards of long-term environmental EMF exposure for fetuses and children. Some studies have suggested EMF exposure in children could induce nervous system disorders. However, gender-dependent effects of microwave radiation exposure on cognitive dysfunction have not previously been reported. Here we investigated whether in utero exposure to 9.417-GHz microwave throughout gestation (Days 3.5–18) affected behavior, using the open field test (OFT), elevated-plus maze (EPM), tail suspension test (TST), forced swimming test (FST) and Morris water maze (MWM). We found that mice showed less movement in the center of an open field (using the OFT) and in an open arm (using the EPM) after in utero exposure to 9.417-GHz radiation, which suggested that the mice had increased anxiety-related behavior. Mice demonstrated reduced immobility in TST and FST after in utero exposure to 9.417-GHz radiation, which suggested that the mice had decreased depression-related behavior. From the MWM test, we observed that male offspring demonstrated decreased learning and memory, while females were not affected in learning and memory, which suggested that microwaves had gender-dependent effects. In summary, we have provided the first experimental evidence of microwaves inducing gender-dependent effects. (author)

  9. Effect of Chronic Exposure to Acidic Environment on Radiosensitivity of Gliosarcoma Cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sora; Kim, Eunhee [Seoul National Univ., Seoul (Korea, Republic of)

    2014-05-15

    In this study, the chronic exposure of cells to acid culture medium, prior or posterior to irradiation, has been investigated for its effect on clonogenic cell survival. Unconventional high-dose radiation therapy, such as SRS, SBRT and MRT, may cause severe vascular damage in tumors, thereby a number of tumor cells facing chronic hypoxia and thus acidosis. According to our observation, gliosarcoma cells become more vulnerable to radiation damage by chronic exposure to acidic condition before irradiation. The longer the preirradiation exposure is, the more vulnerable to radiation damage the cells become. However, the repair of PLD by post-irradiation exposure to acid medium is efficient enough to eliminate the difference in number of the cells carrying PLDs due to different durations of preirradiation exposure to acidic condition.

  10. Double Dose: High Family Conflict Enhances the Effect of Media Violence Exposure on Adolescents’ Aggression

    Directory of Open Access Journals (Sweden)

    Patti M. Valkenburg

    2013-07-01

    Full Text Available We investigated how exposure to media violence and family conflict affects adolescents’ subsequent aggressive behavior. We expected a double dose effect, meaning that high media violence exposure would lead to higher levels of aggression for adolescents in high conflict families compared to low conflict families. A total of 499 adolescents (aged 10 to 14, 48% girls participated in a two-wave longitudinal survey (4-month interval. Survey questions assessed their exposure to violence on television and in electronic games, family conflict, and aggressive behavior. Analyses revealed a significant interaction between media violence and family conflict. In families with higher conflict, higher media violence exposure was related to increased subsequent aggression. This study is the first to show a double dose effect of media violence and family conflict on adolescents’ aggression. These findings underscore the important role of the family in shaping the effects of adolescents’ media use on their social development.

  11. Modelling the effects of ionizing radiation on survival of animal population: acute versus chronic exposure.

    Science.gov (United States)

    Kryshev, A I; Sazykina, T G

    2015-03-01

    The objective of the present paper was application of a model, which was originally developed to simulate chronic ionizing radiation effects in a generic isolated population, to the case of acute exposure, and comparison of the dynamic features of radiation effects on the population survival in cases of acute and chronic exposure. Two modes of exposure were considered: acute exposure (2-35 Gy) and chronic lifetime exposure with the same integrated dose. Calculations were made for a generic mice population; however, the model can be applied for other animals with proper selection of parameter values. In case of acute exposure, in the range 2-11 Gy, the population response was in two phases. During a first phase, there was a depletion in population survival; the second phase was a recovery period due to reparation of damage and biosynthesis of new biomass. Model predictions indicate that a generic mice population, living in ideal conditions, has the potential for recovery (within a mouse lifetime period) from acute exposure with dose up to 10-11 Gy, i.e., the population may recover from doses above an LD50 (6.2 Gy). Following acute doses above 14 Gy, however, the mice population went to extinction without recovery. In contrast, under chronic lifetime exposures (500 days), radiation had little effect on population survival up to integrated doses of 14-15 Gy, so the survival of a population subjected to chronic exposure was much better compared with that after an acute exposure with the same dose. Due to the effect of "wasted radiation", the integrated dose of chronic exposure could be about two times higher than acute dose, producing the same effect on survival. It is concluded that the developed generic population model including the repair of radiation damage can be applied both to acute and chronic modes of exposure; results of calculations for generic mice population are in qualitative agreement with published data on radiation effects in mice. PMID

  12. Affective and behavioral changes following exposure to traumatic events: the moderating effect of religiosity on avoidance behavior among students studying under a high level of terror event exposure.

    Science.gov (United States)

    Korn, Liat; Zukerman, Gil

    2011-12-01

    The goals of this study were to examine the development of affective and behavioral changes following exposure to traumatic events among Israeli students studying under a high level of terror event exposure and to assess the effects of religiosity on those changes development. A questionnaire was administered to 770 students in the Ariel University Center in Judea and Samaria. Higher levels of terror exposure were associated with higher levels of avoidance behavior, subjective feelings of insecurity, and emotional distress. Higher religiosity moderated avoidance behavior, even when controlling for the level of objective exposure to terror events exposure, but had no influence on subjective sense of insecurity, or the level of emotional distress. These findings suggest that religiosity moderates behavioral changes development after traumatic event exposure mainly by reducing avoidance behavior. PMID:21660614

  13. Affective and behavioral changes following exposure to traumatic events: the moderating effect of religiosity on avoidance behavior among students studying under a high level of terror event exposure.

    Science.gov (United States)

    Korn, Liat; Zukerman, Gil

    2011-12-01

    The goals of this study were to examine the development of affective and behavioral changes following exposure to traumatic events among Israeli students studying under a high level of terror event exposure and to assess the effects of religiosity on those changes development. A questionnaire was administered to 770 students in the Ariel University Center in Judea and Samaria. Higher levels of terror exposure were associated with higher levels of avoidance behavior, subjective feelings of insecurity, and emotional distress. Higher religiosity moderated avoidance behavior, even when controlling for the level of objective exposure to terror events exposure, but had no influence on subjective sense of insecurity, or the level of emotional distress. These findings suggest that religiosity moderates behavioral changes development after traumatic event exposure mainly by reducing avoidance behavior.

  14. Effects of Thermal Exposure on Properties of Al-Li Alloys

    Science.gov (United States)

    Shah, Sandeep; Wells, Douglas; Stanton, William; Lawless, Kirby; Russell, Carolyn; Wagner, John; Domack, Marcia; Babel, Henry; Farahmand, Bahram; Schwab, David; Munafo, Paul M. (Technical Monitor)

    2002-01-01

    Aluminum-Lithium (Al-Li) alloys offer significant performance benefits for aerospace structural applications due to their higher specific properties compared with conventional Al alloys. For example, the application of Al-Li alloy 2195 to the space shuffle external cryogenic fuel tank resulted in weight savings of over 7,000 lb, enabling successful deployment of International Space Station components. The composition and heat treatment of 2195 were optimized specifically for strength-toughness considerations for an expendable cryogenic tank. Time-dependent properties related to reliability, such as thermal stability, fatigue, and corrosion, will be of significant interest when materials are evaluated for a reusable cryotank structure. Literature surveys have indicated that there is limited thermal exposure data on Al-Li alloys. The effort reported here was designed to establish the effects of thermal exposure on the mechanical properties and microstructure of Al-Li alloys C458, L277, and 2195 in plate gages. Tensile, fracture toughness, and corrosion resistance were evaluated for both parent metal and friction stir welds (FSW) after exposure to temperatures as high as 300 F for up to 1000 hrs. Microstructural changes were evaluated with thermal exposure in order to correlate with the observed data trends. The ambient temperature parent metal data showed an increase in strength and reduction in elongation after exposure at lower temperatures. Strength reached a peak with intermediate temperature exposure followed by a decrease at highest exposure temperature. Friction stir welds of all alloys showed a drop in elongation with increased length of exposure. Understanding the effect of thermal exposure on the properties and microstructure of Al-Li alloys must be considered in defining service limiting temperatures and exposure times for a reusable cryotank structure.

  15. Chemical mixtures and environmental effects: a pilot study to assess ecological exposure and effects in streams

    Science.gov (United States)

    Buxton, Herbert T.; Reilly, Timothy J.; Kuivila, Kathryn M.; Kolpin, Dana W.; Bradley, Paul M.; Villeneuve, Daniel L.; Mills, Marc A.

    2015-01-01

    Assessment and management of the risks of exposure to complex chemical mixtures in streams are priorities for human and environmental health organizations around the world. The current lack of information on the composition and variability of environmental mixtures and a limited understanding of their combined effects are fundamental obstacles to timely identification and prevention of adverse human and ecological effects of exposure. This report describes the design of a field-based study of the composition and biological activity of chemical mixtures in U.S. stream waters affected by a wide range of human activities and contaminant sources. The study is a collaborative effort by the U.S. Geological Survey and the U.S. Environmental Protection Agency. Scientists sampled 38 streams spanning 24 States and Puerto Rico. Thirty-four of the sites were located in watersheds impacted by multiple contaminant sources, including industrial and municipal wastewater discharges, crop and animal agricultural runoff, urban runoff, and other point and nonpoint contaminant sources. The remaining four sites were minimally development reference watersheds. All samples underwent comprehensive chemical and biological characterization, including sensitive and specific direct analysis for over 700 dissolved organic and inorganic chemicals and field parameters, identification of unknown contaminants (environmental diagnostics), and a variety of bioassays to evaluate biological activity and toxicity.

  16. Effect of exposure cycle on hot salt stress corrosion of a titanium alloy

    Science.gov (United States)

    Gray, H. R.; Johnston, J. R.

    1974-01-01

    The influence of exposure cycle on the hot-salt stress-corrosion cracking resistance of the Ti-8Al-1Mo-1V alloy was determined. Both temperature and stress were cycled simultaneously to simulate turbine-powered aircraft service cycles. Temperature and stress were also cycled independently to determine their individual effects. Substantial increases in crack threshold stresses were observed for cycles in which both temperature and stress or temperature alone were applied for 1 hour and removed for 3 hours. The crack threshold stresses for these cyclic exposures were twice those determined for continuous exposure for the same total time of 96 hours.

  17. Glyphosate accumulation, translocation, and biological effects in Coffea arabica after single and multiple exposures

    DEFF Research Database (Denmark)

    Schrübbers, Lars Christoph; Valverde, Bernal E.; Strobel, Bjarne W.;

    2016-01-01

    In perennial crops like coffee, glyphosate drift exposure can occur multiple times during its commercial life span. Due to limited glyphosate degradation in higher plants, a potential accumulation of glyphosate could lead to increased biological effects with increased exposure frequency....... In this study, we investigated glyphosate translocation over time, and its concentration and biological effects after single and multiple simulated spray-drift exposures. Additionally, shikimic acid/glyphosate ratios were used as biomarkers for glyphosate binding to its target enzyme.Four weeks after...... the exposure, glyphosate was continuously translocated. Shikimic acid levels were lin-ear correlated with glyphosate levels. After two months, however, glyphosate appeared to have reduced activity. In the greenhouse, multiple applications resulted in higher internal glyphosate concentrations.The time...

  18. Resisting temptation: effects of exposure to a forbidden food on eating behaviour.

    Science.gov (United States)

    Soetens, Barbara; Braet, Caroline; Van Vlierberghe, Leen; Roets, Arne

    2008-07-01

    The study tests existing evidence on the paradoxical effects of exposure to a forbidden snack. Sixty-eight females were assigned randomly to one of two conditions: a temptation group, who were given the instruction to abstain from a favourite snack for 24h while being exposed to it, or a control group, who were given no specific instructions. A further distinction was made between high-restraint/high-disinhibition (n=21), high-restraint/low-disinhibition (n=20) and low-restraint participants (n=27) based on DEBQ subscale scores. After exposure to the foods, all participants were given free access to the food. Participants ate more of the snack after abstinence with exposure. The high-restraint/high-disinhibition group in particular displayed a substantial disinhibition effect. Results indicate that prohibition with exposure may backfire and increase the risk of loss of control over eating behaviour, particularly in at-risk groups of disinhibited restrained eaters.

  19. Dioxin-like exposures and effects on estrogenic and androgenic exposures and micronuclei frequency in mother-newborn pairs

    DEFF Research Database (Denmark)

    Pedersen, Marie; Halldorsson, Thorhallur I; Mathiesen, Line;

    2010-01-01

    In utero exposure to environmental dioxin-like, estrogen and androgen compounds can cause adverse health effects. Little is known about potential interactions in vivo between dioxin-like compounds, estrogens and androgens during fetal development in humans. Therefore we explored the potential...... interactions in vivo between dioxin-like compounds, estrogens, androgens using chemical-activated luciferase expression (CALUX)(R) bioassays in maternal and umbilical cord blood plasma concurrently collected at the time of planned Caesarean section from 98 healthy pregnancies. The dioxin-like activity was also...... determined after placental transfer of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the ex vivo human placenta perfusion system. Similar dioxin-like activity in maternal and cord blood (37 versus 33pg CALUX(R)-TEQ/g plasma lipids, P>0.05) was detected and it demonstrates transplacental transfer. Increased...

  20. Histopathologic effects of formaldehyde exposure on rat kidney

    Directory of Open Access Journals (Sweden)

    M.J. Golalipour

    2007-01-01

    Full Text Available AbstractBackground and purpose: Formaldehyde is a chemical traditionally used for fixing the cadaver. It is vaporized during dissection and practical studying on cadaver. Studies show that this vapour can cause some clinical sympotms such as throat, eye, skin and nasal irritation.This study was designed to determine the histopathological changes of rat kidney tissue exposed to formaldehyde for 18 weeks.Materials and Methods: This study was performed on 28, 6-7 weeks postnatal albino Wistar rats. The rats were divided into 3 case groups (E1: 4hrs/d, 4d/w; E2: 2hrs/d, 4d/w; E3: 2hrs/d, 2d/w and one control group (C. The kidney specimens were sectioned and stained with H&E technique for histopathological study.Results: In all histopathology sections of groups E1, E2 and E3, the following similar changes were observed: Mild congestion in the glumeroles, focal congestion and vacuolar (hydropic degeneration of tubular cells only mild non-specific congestion in renal vessels. There were no evidences of fibrotic change or inflammatory cells infiltration among interstitial tissue. Also there were no abnormalities in the staining of nucleus and cytoplasm. In Control group (C, no histopathologic changes were observed.Conclusion: The results of this study showed that formaldehyde vapour with a concentrations used in our study, can not induce histopathologic changes which could be detectable by light microscope. Also, there is no direct relationship between the duration of exposure to formaldehyde vapour and the intensity of histopathologic changes in the kidney.

  1. Effect of wood smoke exposure on vascular function and thrombus formation in healthy fire fighters

    OpenAIRE

    Hunter, Amanda L; Unosson, Jon; Bosson, Jenny A.; Langrish, Jeremy P; Pourazar, Jamshid; Raftis, Jennifer B; Miller, Mark R; Lucking, Andrew J.; Boman, Christoffer; Nyström, Robin; Donaldson, Kenneth; Flapan, Andrew D; Shah, Anoop; Pung, Louis; Sadiktsis, Ioannis

    2014-01-01

    Background Myocardial infarction is the leading cause of death in fire fighters and has been linked with exposure to air pollution and fire suppression duties. We therefore investigated the effects of wood smoke exposure on vascular vasomotor and fibrinolytic function, and thrombus formation in healthy fire fighters. Methods In a double-blind randomized cross-over study, 16 healthy male fire fighters were exposed to wood smoke (~1 mg/m3 particulate matter concentration) or filtered air for on...

  2. STUDIES OF EFFECTS OF GSM-900 MICROWAVE EXPOSURE ON DNA ”MICRONUCLEUS” FORMATION IN MICE

    OpenAIRE

    Gravé, Jan; Abrahamsson Zetterberg, Lilianne; Persson, Bertil R.; Salford, Leif

    2012-01-01

    Possible genotoxic effects of microwave exposure from GSM-900 mobile telephones have investigated with in vivo micronucleus assay of mouse erythrocytes from CBA mice and GFAP knockout mice. No significant change in the frequency of erythrocytes with micronuclei neither in the young (polychromatic PCE) or mature (normichromatic NCE) erythrocytes. There is, however, a tendency but not significant to increased MPCE in female mice after 35 days of exposure. There is a marked tendency to lower PCE...

  3. Offspring of prenatal IV nicotine exposure exhibit increased sensitivity to the reinforcing effects of methamphetamine

    OpenAIRE

    StevenBrownHarrod

    2012-01-01

    Maternal smoking during pregnancy is associated with increased substance abuse in offspring. Preclinical research shows that in utero exposure to nicotine, the primary psychoactive compound in tobacco smoke, influences the neurodevelopment of reward systems and alters motivated behavior in offspring. The present study determined if prenatal nicotine (PN) exposure altered the sensitivity to the reinforcing and aversive effects of methamphetamine (METH) in offspring using a low dose, intraven...

  4. Effects of Radiation Exposure From Cardiac Imaging: How Good Are the Data?

    OpenAIRE

    Einstein, Andrew J.

    2012-01-01

    Concerns about medical exposure to ionizing radiation have become heightened in recent years due to rapid growth in procedure volumes and the high radiation doses incurred from some procedures. This article summarizes the evidence base undergirding concerns about radiation exposure in cardiac imaging. After classifying radiation effects, explaining terminology used to quantify the radiation received by patients, and describing typical doses from cardiac imaging procedures, I address the major...

  5. Brewing complications: the effect of acute ethanol exposure on wound healing

    OpenAIRE

    Radek, Katherine A.; Ranzer, Matthew J.; DiPietro, Luisa A.

    2009-01-01

    Ethanol consumption is linked to a higher incidence of traumatic wounds and increases the risk for morbidity and mortality following surgical or traumatic injury. One of the most profound effects of acute ethanol exposure on wound healing occurs during the inflammatory response, and altered cytokine production is a primary component. Acute ethanol exposure also impairs the proliferative response during healing, causing delays in epithelial coverage, collagen synthesis, and blood vessel regrow...

  6. Effects of phthalate exposure on asthma may be mediated through alterations in DNA methylation

    OpenAIRE

    Wang, I-Jen; Karmaus, Wilfried JJ; Chen, Su-Lien; Holloway, John W.; Ewart, Susan

    2015-01-01

    Background Phthalates may increase the asthma risk in children. Mechanisms underlying this association remain to be addressed. This study assesses the effect of phthalate exposures on epigenetic changes and the role of epigenetic changes for asthma. In the first step, urine and blood samples from 256 children of the Childhood Environment and Allergic diseases Study (CEAS) were analyzed. Urine 5OH-MEHP levels were quantified as an indicator of exposure, and asthma information was collected. DN...

  7. Offspring of Prenatal IV Nicotine Exposure Exhibit Increased Sensitivity to the Reinforcing Effects of Methamphetamine

    OpenAIRE

    Harrod, Steven B.; Lacy, Ryan T.; Morgan, Amanda J.

    2012-01-01

    Maternal smoking during pregnancy is associated with increased substance abuse in offspring. Preclinical research shows that in utero exposure to nicotine, the primary psychoactive compound in tobacco smoke, influences the neurodevelopment of reward systems and alters motivated behavior in offspring. The present study determined if prenatal nicotine (PN) exposure altered the sensitivity to the reinforcing and aversive effects of methamphetamine (METH) in offspring using a low dose, intravenou...

  8. Understanding Environmental Tobacco Smoke Exposure and Effects in Asthmatic Children through Determination of Urinary Cotinine and Targeted Metabolomics of Plasma

    Science.gov (United States)

    Understanding Environmental Tobacco Smoke Exposure and Effects in Asthmatic Children through Determination of Urinary Cotinine and Targeted Metabolomics of Plasma Introduction Asthma is a complex disease with multiple triggers and causal factors, Exposure to environmental tob...

  9. Hypoxia Stress Test Reveals Exaggerated Cardiovascular Effects in Hypertensive Rats after Exposure to the Air Pollutant Acrolein

    Science.gov (United States)

    Exposure to air pollution increases the risk of cardiovascular morbidity and mortality, especially in susceptible populations with cardiovascular disease. Stress tests are useful in assessing cardiovascular risk and manifesting latent effects of exposure. The goal of this study w...

  10. The effects of maternal depression and maternal selective serotonin reuptake inhibitor exposure on the offspring

    Directory of Open Access Journals (Sweden)

    Jocelien DA Olivier

    2013-05-01

    Full Text Available It has been estimated that 20% of pregnant women suffer from depression and it is well documented that maternal depression can have long-lasting effects on the child. Currently, common treatment for maternal depression has been the selective serotonin reuptake inhibitor medications (SSRIs which are used by 2-3% of pregnant women in the Nordic countries and by up to 10% of pregnant women in the United States. Antidepressants cross the placenta and are transferred to the fetus, thus, the question arises as to whether children of women taking antidepressants are at risk for altered neurodevelopmental outcomes and, if so, whether the risks are due to SSRI medication exposure or to the underlying maternal depression. This review considers the effects of maternal depression and SSRI exposure on offspring development in both clinical and preclinical populations. As it is impossible in humans to study the effects of SSRIs without taking into account the possible underlying effects of maternal depression (healthy pregnant women do not take SSRIs, animal models are of great value. For example, rodents can be used to determine the effects of maternal depression and/or perinatal SSRI exposure on offspring outcomes. Unraveling the joint (or separate effects of maternal depression and SSRI exposure will provide more insights into the risks or benefits of SSRI exposure during gestation and will help women make informed decisions about using SSRIs during pregnancy.

  11. Procesos de corrosión debidos a corrientes alternas inducidas (60 Hz

    Directory of Open Access Journals (Sweden)

    Vera, E.

    1996-10-01

    Full Text Available The phenomenon by which a sinusoidal a.c. signal damages a steel in contact with an aggressive electrolite was determined. Thus, a series of electrochemical tests was carried out, when a signal of the previously mentioned characteristics is present in the metal-electrolite interphase, both with cathodic protection and without it. The results allowed to postulate an empirical relationship that determines the corrosive process kinetics exerted by the action of an alternating signal. The phenomenon by which the AC signal generates a corrosion state over a probe was determined from the physical point of view.

    Se determinó el fenómeno por el que una señal de c.a. de tipo sinusoidal genera fenómenos de corrosión en un acero en contacto con un electrólito agresivo. Para ello, se realizaron pruebas electroquímicas cuando una señal de las anteriores características está presente en la interfase metal-electrólito, con y sin protección catódica. Los resultados permitieron postular una relación empírica que determina la cinética del proceso corrosivo ejercido por la acción de la señal alterna. Se determinó, desde un punto de vista físico, el fenómeno por el cual la señal de c.a. genera un estado de corrosión sobre la probeta.

  12. Alcohol-cue exposure effects on craving and attentional bias in underage college-student drinkers.

    Science.gov (United States)

    Ramirez, Jason J; Monti, Peter M; Colwill, Ruth M

    2015-06-01

    The effect of alcohol-cue exposure on eliciting craving has been well documented, and numerous theoretical models assert that craving is a clinically significant construct central to the motivation and maintenance of alcohol-seeking behavior. Furthermore, some theories propose a relationship between craving and attention, such that cue-induced increases in craving bias attention toward alcohol cues, which, in turn, perpetuates craving. This study examined the extent to which alcohol cues induce craving and bias attention toward alcohol cues among underage college-student drinkers. We designed within-subject cue-reactivity and visual-probe tasks to assess in vivo alcohol-cue exposure effects on craving and attentional bias on 39 undergraduate college drinkers (ages 18-20). Participants expressed greater subjective craving to drink alcohol following in vivo cue exposure to a commonly consumed beer compared with water exposure. Furthermore, following alcohol-cue exposure, participants exhibited greater attentional biases toward alcohol cues as measured by a visual-probe task. In addition to the cue-exposure effects on craving and attentional bias, within-subject differences in craving across sessions marginally predicted within-subject differences in attentional bias. Implications for both theory and practice are discussed. (PsycINFO Database Record PMID:25243832

  13. Alcohol-cue exposure effects on craving and attentional bias in underage college-student drinkers.

    Science.gov (United States)

    Ramirez, Jason J; Monti, Peter M; Colwill, Ruth M

    2015-06-01

    The effect of alcohol-cue exposure on eliciting craving has been well documented, and numerous theoretical models assert that craving is a clinically significant construct central to the motivation and maintenance of alcohol-seeking behavior. Furthermore, some theories propose a relationship between craving and attention, such that cue-induced increases in craving bias attention toward alcohol cues, which, in turn, perpetuates craving. This study examined the extent to which alcohol cues induce craving and bias attention toward alcohol cues among underage college-student drinkers. We designed within-subject cue-reactivity and visual-probe tasks to assess in vivo alcohol-cue exposure effects on craving and attentional bias on 39 undergraduate college drinkers (ages 18-20). Participants expressed greater subjective craving to drink alcohol following in vivo cue exposure to a commonly consumed beer compared with water exposure. Furthermore, following alcohol-cue exposure, participants exhibited greater attentional biases toward alcohol cues as measured by a visual-probe task. In addition to the cue-exposure effects on craving and attentional bias, within-subject differences in craving across sessions marginally predicted within-subject differences in attentional bias. Implications for both theory and practice are discussed. (PsycINFO Database Record

  14. Effect of Electromagnetic Pulse Exposure on Brain Micro Vascular Permeability in Rats

    Institute of Scientific and Technical Information of China (English)

    GUI-RONG DING; KANG-CHU LI; XIAO-WU WANG; YONG-CHUN ZHOU; LIAN-BO QIU; JUAN TAN; SHENG-LONG XU; GUO-ZHEN GUO

    2009-01-01

    Objective To observe the effect of electromagnetic pulse (EMP) exposure on cerebral micro vascular permeability in rats.Methods The whole-body of male Sprague-Dawley rats were exposed or sham exposed to 200 pulses or 400 pulses (1 Hz) of EMP at 200 kV/m.At 0.5,1,3,6,and 12 h after EMP exposure,the permeability of cerebral micro vascular was detected by transmission electron microscopy and immunohistochemistry using lanthanum nitrate and endogenous albumin as vascular tracers,respectively. Results The lanthanum nitrate tracer was limited to the micro vascular lumen with no lanthanum nitrate or albumin tracer extravasation in control rat brain.After EMP exposure,the lanthanum nitrate ions reached the tight junction,basal lamina and pericapillary tissue.Similarly,the albumin immunopositive staining was identified in pericapillary tissue.The changes in brain micro vascular permeability were transient,the leakage of micro vascular vessels appeared at 1 h,and reached its peak at 3 h,and nearly recovered at 12 h,after EMP exposure.In addition,the leakage of micro vascular was more obvious after exposure of EMP at 400 pulses than after exposure of EMP at 200 pulses. Conclusion Exposure to 200 and 400 pulses (1 Hz) of EMP at 200 kV/m can increase cerebral micro vascular permeability in rats,which is recoverable.

  15. The effects of heat exposure on the membranous structure of rat's intestinalepithelium and the biochemical indexes

    Institute of Scientific and Technical Information of China (English)

    Guo Biao Zhu; Ji Hong Li

    2000-01-01

    AIM To study the effects of heat exposure and swimming on membranous structure of the small intestinalepithelium and the biochemical indexes.METHODS The distribution of the intra-membranous particles (IMPs) in enteric epithelium of SD rats andthe number of IMPs were analyzed with freeze-etching technique and TxB2, PGFIa, PRL, CORT and totalSA (TSA) were measured with the techniques of biochemistry and radio-immunity.RESULTS Heat exposure markedly affected the distributive pattern of IMPs in intestinal epithelium andmade the numbers of IMPs on the PF and EF faces of cell membrane and nuclear membrane decreased.Swimming exacerbated the above changes. And in the meantime heat exposure resulted in the massivereleasing of the body-hurting substance as TxB2 and reducing of the body-protecting substance as PGFIa.TSA increased obviously. These changes recovered partly after heat exposure, but the number of IMPs onboth PF and EF faces and certain biochemical indexes were still not restored to the levels as in the controlgroup.CONCLUSION Heat exposure and swimming can make the cellular catabolism accelerated and anabolismreduced, then bring about the numbers of IMPs of intestinal epithelium membrane and nuclear membranedecreased, and the distribution was abnormal. TxB2, PGFIa, PRL, CORT and TSA were changedabnormally during heat exposure. And above indexes showed no notable evidence of recovery after stoppingheat exposure 4 hours-24 hours; the delayed injury was obviously presented.

  16. Growth Retardation and Altered Isotope Composition As Delayed Effects of PCB Exposure in Daphnia magna.

    Science.gov (United States)

    Ek, Caroline; Gerdes, Zandra; Garbaras, Andrius; Adolfsson-Erici, Margaretha; Gorokhova, Elena

    2016-08-01

    Trophic magnification factor (TMF) analysis employs stable isotope signatures to derive biomagnification potential for environmental contaminants. This approach relies on species δ(15)N values aligning with their trophic position (TP). This, however, may not always be true, because toxic exposure can alter growth and isotope allocation patterns. Here, effects of PCB exposure (mixture of PCB18, PCB40, PCB128, and PCB209) on δ(15)N and δ(13)C as well as processes driving these effects were explored using the cladoceran Daphnia magna. A two-part experiment assessed effects of toxic exposure during and after exposure; juvenile daphnids were exposed during 3 days (accumulation phase) and then allowed to depurate for 4 days (depuration phase). No effects on survival, growth, carbon and nitrogen content, and stable isotope composition were observed after the accumulation phase, whereas significant changes were detected in adults after the depuration phase. In particular, a significantly lower nitrogen content and a growth inhibition were observed, with a concomitant increase in δ(15)N (+0.1 ‰) and decrease in δ(13)C (-0.1 ‰). Although of low magnitude, these changes followed the predicted direction indicating that sublethal effects of contaminant exposure can lead to overestimation of TP and hence underestimated TMF. PMID:27367056

  17. Experimental effects of exposure to pornography: the moderating effect of personality and mediating effect of sexual arousal.

    Science.gov (United States)

    Hald, Gert Martin; Malamuth, Neil N

    2015-01-01

    Using a randomly selected community sample of 200 Danish young adult men and women in a randomized experimental design, the study investigated the effects of a personality trait (agreeableness), past pornography consumption, and experimental exposure to non-violent pornography on attitudes supporting violence against women (ASV). We found that lower levels of agreeableness and higher levels of past pornography consumption significantly predicted ASV. In addition, experimental exposure to pornography increased ASV but only among men low in agreeableness. This relationship was found to be significantly mediated by sexual arousal with sexual arousal referring to the subjective assessment of feeling sexually excited, ready for sexual activities, and/or bodily sensations associated with being sexually aroused. In underscoring the importance of individual differences, the results supported the hierarchical confluence model of sexual aggression and the media literature on affective engagement and priming effects. PMID:24729134

  18. Health effects of non-occupational exposure to oil extraction

    OpenAIRE

    O’Callaghan-Gordo, Cristina; Orta-Martínez, Martí; Kogevinas, Manolis

    2016-01-01

    Oil extraction may cause extensive environmental impact that can affect health of populations living in surrounding areas. Large populations are potentially exposed to oil extraction related contamination through residence in areas where oil extraction is conducted, especially in low and middle income countries (LMICs). Health effects among people residentially exposed to upstream...

  19. Health effects assessment of exposure to particles from wood smoke

    DEFF Research Database (Denmark)

    Nielsen, Elsa; Dybdahl, Marianne; Larsen, Poul Bo

    Based on an extensive literature survey the reports concludes that particles from wood smoke should be considered as harmful to health and that effects from these particles can not be considered as less severe compared to ambient air particles in general or diesel particles. In DK there is about...

  20. High-resolution simulations of the thermophysiological effects of human exposure to 100 MHz RF energy

    International Nuclear Information System (INIS)

    Human exposure to radio frequency (RF) electromagnetic energy is known to result in tissue heating and can raise temperatures substantially in some situations. Standards for safe exposure to RF do not reflect bio-heat transfer considerations however. Thermoregulatory function (vasodilation, sweating) may mitigate RF heating effects in some environments and exposure scenarios. Conversely, a combination of an extreme environment (high temperature, high humidity), high activity levels and thermally insulating garments may exacerbate RF exposure and pose a risk of unsafe temperature elevation, even for power densities which might be acceptable in a normothermic environment. A high-resolution thermophysiological model, incorporating a heterogeneous tissue model of a seated adult has been developed and used to replicate a series of whole-body exposures at a frequency (100 MHz) which approximates that of human whole-body resonance. Exposures were simulated at three power densities (4, 6 and 8 mW cm−2) plus a sham exposure and at three different ambient temperatures (24, 28 and 31 °C). The maximum hypothalamic temperature increase over the course of a 45 min exposure was 0.28 °C and occurred in the most extreme conditions (Tamb = 31 °C, PD = 8 mW cm−2). Skin temperature increases attributable to RF exposure were modest, with the exception of a ‘hot spot’ in the vicinity of the ankle where skin temperatures exceeded 39 °C. Temperature increases in internal organs and tissues were small, except for connective tissue and bone in the lower leg and foot. Temperature elevation also was noted in the spinal cord, consistent with a hot spot previously identified in the literature. (paper)

  1. Instability in an amorphous In-Ga-Zn-O field effect transistor upon water exposure

    Science.gov (United States)

    Sharma, Bhupendra K.; Ahn, Jong-Hyun

    2016-02-01

    The instability of an amorphous indium-gallium-zinc oxide (IGZO) field effect transistor is investigated upon water treatment. Electrical characteristics are measured before, immediately after and a few days after water treatment in ambient as well as in vacuum conditions. It is observed that after a few days of water exposure an IGZO field effect transistor (FET) shows relatively more stable behaviour as compared to before exposure. Transfer characteristics are found to shift negatively after immediate water exposure and in vacuum. More interestingly, after water exposure the off current is found to decrease by 1-2 orders of magnitude and remains stable even after 15 d of water exposure in ambient as well as in vacuum, whereas the on current more or less remains the same. An x-ray photoelectron spectroscopic study is carried out to investigate the qualitative and quantitative analysis of IGZO upon water exposure. The changes in the FET parameters are evaluated and attributed to the formation of excess oxygen vacancies and changes in the electronic structure of the IGZO bulk channel and at the IGZO/SiO2 interface, which can further lead to the formation of subgap states. An attempt is made to distinguish which parameters of the FET are affected by the changes in the electronic structure of the IGZO bulk channel and at the IGZO/SiO2 interface separately.

  2. Modelling the effect of exposure to environmetal carcinogens on incidence of cancers in populations

    International Nuclear Information System (INIS)

    Risk estimation is a complex problem with very important public health consequences. The models in general use for this purpose are simple models that describe some measure of risk as a mathematically simple function of exposure. The available data about environmental carcinogens, however, is rarely enough to allow the authors to test the validity of such models. A solution to this problem is to choose a model that agrees with the understanding of carcinogenesis and exposure effects. Here, exposure effects are modelled quantitative in the framework of a model for carcinogenesis at the cellular level proposed by Moolgavkar and Knudson (1981). The model postulates that a normal cell must undergo two changes before it becomes malignant. It also allows for growth of normal tissue, intermediate cell clones and malignant tumors. Derivations of hazards and relative risks based on various patterns (acute, chronic) and qualities (initiators, promoters) of exposure are shown. The use of such models for data analysis is illustrated on two sets of data: one on acute exposure to γ-rays in an animal carcinogensis experiment; the other on a chronic exposure to arsenic in a cohort of workers from a copper smelter. Results from the analysis are compared to those obtained with standard methods of risk estimation

  3. Instability in an amorphous In–Ga–Zn–O field effect transistor upon water exposure

    International Nuclear Information System (INIS)

    The instability of an amorphous indium–gallium–zinc oxide (IGZO) field effect transistor is investigated upon water treatment. Electrical characteristics are measured before, immediately after and a few days after water treatment in ambient as well as in vacuum conditions. It is observed that after a few days of water exposure an IGZO field effect transistor (FET) shows relatively more stable behaviour as compared to before exposure. Transfer characteristics are found to shift negatively after immediate water exposure and in vacuum. More interestingly, after water exposure the off current is found to decrease by 1–2 orders of magnitude and remains stable even after 15 d of water exposure in ambient as well as in vacuum, whereas the on current more or less remains the same. An x-ray photoelectron spectroscopic study is carried out to investigate the qualitative and quantitative analysis of IGZO upon water exposure. The changes in the FET parameters are evaluated and attributed to the formation of excess oxygen vacancies and changes in the electronic structure of the IGZO bulk channel and at the IGZO/SiO2 interface, which can further lead to the formation of subgap states. An attempt is made to distinguish which parameters of the FET are affected by the changes in the electronic structure of the IGZO bulk channel and at the IGZO/SiO2 interface separately. (paper)

  4. Effects of lead exposure on licking and yawning behaviour in rats

    Energy Technology Data Exchange (ETDEWEB)

    Ghazi-Khansari, Mahmoud; Rezvani, Niloufar; Bani-Assadi, Shadi; Zarrindast, Mohammad-Reza [Tehran Univ. of Medical Sciences, School of Medicine, Dept. of Pharmacology (Iran, Islamic Republic of)

    1998-12-01

    In the present study, effects of lead exposure on licking and yawning behaviour have been studied. The dopaminergic receptor agonist, apomorphine (0.15, 0.25 and 0.5 mg/kg), induced dose-dependent licking in rats. The maximum response was obtained with 0.5 mg/kg of the apomorphine. Lead acetate (0.5%) exposure significantly increased apomorphine-induced licking. Yawning induced by the D{sub 2} dopaminergic agonist, bromocriptine (2, 3, 4, 8 mg/kg), and the cholinergic drug, physostigmine (0.1 or 0.3 mg/kg), was significantly decreased by lead acetate (0.05%) exposure. It may be concluded that the behaviour induced by dopaminergic or cholinergic agents can be affected by lead subchronic exposure. (au) 30 refs.

  5. Toxic exposure to ethylene dibromide and mercuric chloride: effects on laboratory-reared octopuses.

    Science.gov (United States)

    Adams, P M; Hanlon, R T; Forsythe, J W

    1988-01-01

    The effects of acute and chronic exposure to either ethylene dibromide (EDB) or mercuric chloride (MC) were studied in laboratory-reared Octopus joubini, O. maya and O. bimaculoides. The advantages of using octopuses were that the responses were immediate, highly visible and sensitive. All species demonstrated signs of toxicity to acute and chronic exposure to EDB and to MC. A dosage-sensitive relationship for the loss and subsequent recovery of locomotor response and of chromatophore expansion was found for each species after acute exposure. For each species the LC50 for chronic exposure occurred within 12 hr at 100 mg/l for EDB and within 3 hr at 1,000 mg/l for MC. This study demonstrated the potential usefulness of laboratory-reared octopuses in evaluating the toxicity of marine environmental pollutants. PMID:3072470

  6. Prenatal exposure to diesel exhaust particles and effect on the male reproductive system in mice

    DEFF Research Database (Denmark)

    Hemmingsen, Jette Gjerke; Hougaard, Karin Sørig; Talsness, Chris;

    2009-01-01

    In utero exposure to diesel exhaust particles may reduce sperm production in adulthood. We investigated the effect of prenatal exposure to diesel exhaust particles on the male reproductive system and assessed endocrine disruption and regulation of aquaporin expression as possible mechanisms...... compared to controls. These data indicate that prenatal exposure to SRM2975 was not associated with endocrine disruptor activity in adulthood. There was no significant change in expression levels of aquaporins 7, 8 and 9 in testes tissue, measured as mRNA expression and protein levels...... by immunohistochemistry. In conclusion, prenatal exposure to SRM2975 was associated with reduced daily sperm production in adulthood, which was not possible to clearly associate with altered endocrine function or expression of aquaporins in the testes....

  7. Dietary modulation of the effects of exposure to 56Fe particles

    Science.gov (United States)

    Rabin, B. M.; Joseph, J. A.; Shukitt-Hale, B.; Carey, A. N.

    On exploratory missions to other planets, astronauts will be exposed to galactic cosmic rays composed of protons and heavy particles, such as 56Fe. Long-term exposure to these particles can cause cancer. However, there are significant uncertainties in the risk estimates for the probability of developing heavy particle-induced cancer, and in the amount of shielding needed to provide an adequate level of radiation protection. The results of this preliminary study, using a ground-based model for exposure to cosmic rays, show reduced tumorigenesis in rats maintained on diets containing blueberry or strawberry extract prior to exposure to 56Fe particles. Because the study was not initially designed to evaluate tumorigenesis following exposure to 56Fe particles, additional research is needed to evaluate the effectiveness of strawberry and blueberry supplementation. However, the preliminary results presented in this study suggest that diets containing antioxidant phytochemicals can provide additional radiation protection on interplanetary voyages.

  8. CARDIOVASCULAR AND OTHER HEALTH EFFECTS ASSOCIATED WITH ARSENIC EXPOSURE IN INNER MONGOLIA

    Science.gov (United States)

    Arsenic exposure is associated with cardiovascular and other health effects. The study objectives were to investigate the mode of action and to assess dose-response relationships of arsenic on cardiovascular, diabetic and carcinogenic effects in Ba Men, Inner Mongolia. Ba Men res...

  9. Effectiveness of a Multidimensional Randomized Control Intervention to Reduce Quartz Exposure Among Construction Workers

    NARCIS (Netherlands)

    Deurssen, E. van; Meijster, T; Oude Hengel, K.M.; Boessen, R.; Spaan, S.; Tielemans, E.; Heederik, D.; Pronk, A.

    2015-01-01

    There is little evidence with respect to the effectiveness of intervention programs that focus on the reduction of occupational quartz exposure in the construction industry. This article evaluates the effectiveness of a multidimensional intervention which was aimed at reducing occupational quartz ex

  10. Effects of C60 nanoparticle exposure on earthworms (Lumbricus rubellus) and implications for population dynamics

    NARCIS (Netherlands)

    Ploeg, van der M.J.C.; Baveco, J.M.; Hout, van der A.; Rietjens, I.M.C.M.; Brink, van den N.W.

    2011-01-01

    Effects of C60 nanoparticles (nominal concentrations 0, 15.4 and 154 mg/kg soil) on mortality, growth and reproduction of Lumbricus rubellus earthworms were assessed. C60 exposure had a significant effect on cocoon production, juvenile growth rate and mortality. These endpoints were used to model ef

  11. Differential effects of exposure to ambient vanilla and citris aromas on mood, arousal and food choice

    NARCIS (Netherlands)

    Wijk, de R.A.; Zijlstra, S.

    2012-01-01

    Background Aromas have been associated with physiological, psychological affective and behavioral effects. We tested whether effects of low-level exposure to two ambient food-related aromas (citrus and vanilla) could be measured with small numbers of subjects, low-cost physiological sensors and semi

  12. Exposure - dependent effects of ethanol on the innate immune system

    OpenAIRE

    Goral, Joanna; Karavitis, John; Kovacs, Elizabeth J.

    2008-01-01

    Extensive evidence indicates that ethanol (alcohol) has immunomodulatory properties. Many of its effects on innate immune response are dose-dependent, with acute or moderate use associated with attenuated inflammatory responses, and heavy ethanol consumption linked with augmentation of inflammation. Ethanol may modify innate immunity via functional alterations of the cells of the innate immune system. Mounting evidence indicates that ethanol can diversely affect antigen recognition and intrac...

  13. Predictive modeling of nanomaterial exposure effects in biological systems

    OpenAIRE

    Liu X; Tang K.; Harper S.; Harper B; Steevens JA; Xu R

    2013-01-01

    Xiong Liu,1 Kaizhi Tang,1 Stacey Harper,2 Bryan Harper,2 Jeffery A Steevens,3 Roger Xu1 1Intelligent Automation, Inc., Rockville, MD, USA; 2Department of Environmental and Molecular Toxicology, School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, OR, USA; 3ERDC Environmental Laboratory, Vicksburg, MS, USA Background: Predictive modeling of the biological effects of nanomaterials is critical for industry and policymakers to assess the potential ha...

  14. Immune effects of respiratory exposure to fragrance chemicals

    OpenAIRE

    Ezendam J; de Klerk A; Cassee FR; Fokkens PHB; van der Zee Park M; van Loveren H; Jong WH de; GBO

    2007-01-01

    Inhalation of the fragrance chemicals, isoeugenol and cinnamal, by mice resulted in immune reactions in the respiratory tract. This was observed in experiments performed by the RIVM (National Institute for Public Health and the Enviroment) of which results indicate that inhalation of some fragrance chemicals could induce unwanted effects on the immune system. Fragrance chemicals are common ingredients in such consumer products as cosmetics and scented products. Several fragrance chemicals are...

  15. Pathobiochemical effects in rat lung related to episodic ozone exposure

    OpenAIRE

    van Bree L; Rombout PJA; Rietjens IMCM; Dormans JAMA; Marra M

    1989-01-01

    Correlatie van luchtmetingen van ozon met gegevens over gezondheidseffecten suggereren dat de huidige ozonnorm de volksgezondheid onvoldoende beschermt. Om expositie-effect relaties voor ozon te ontwikkelen, werd de huidige studie opgezet, waarbij ratten werden blootgesteld gedurende een aantal opeenvolgende dagen, daarmee een luchtverontreinigingsepisode simulerend. De acute longschade en onsteking na expositie aan 0.4 ppm ozon bleek voornamelijk veroorzaakt te worden door de eerste expositi...

  16. Rays Sting: The Acute Cellular Effects of Ionizing Radiation Exposure.

    Science.gov (United States)

    Franco, A; Ciccarelli, M; Sorriento, D; Napolitano, L; Fiordelisi, A; Trimarco, B; Durante, M; Iaccarino, G

    2016-05-01

    High-precision radiation therapy is a clinical approach that uses the targeted delivery of ionizing radiation, and the subsequent formation of reactive oxygen species (ROS) in high proliferative, radiation sensitive cancers. In particular, in thoracic cancer ratdiation treatments, can not avoid a certain amount of cardiac toxicity. Given the low proliferative rate of cardiac myocytes, research has looked at the effect of radiation on endothelial cells and consequent coronary heart disease as the mechanism of ratdiation induced cardiotoxicity. In fact, little is known concerning the direct effect of radiation on mitochondria dynamis in cardiomyocyte. The main effect of ionizing radiation is the production of ROS and recent works have uncovered that they directly participates to pivotal cell function like mitochondrial quality control. In particular ROS seems to act as check point within the cell to promote either mitochondrial biogenesis and survival or mitochondrial damage and apoptosis. Thus, it appears evident that the functional state of the cell, as well as the expression patterns of molecules involved in mitochondrial metabolism may differently modulate mitochondrial fate in response to radiation induced ROS responses. Different molecules have been described to localize to mitochondria and regulate ROS production in response to stress, in particular GRK2. In this review we will discuss the evidences on the cardiac toxicity induced by X ray radiation on cardiomyocytes with emphasis on the role played by mitochondria dynamism.

  17. Embriotoxic effects of maternal exposure to Tityus serrulatus scorpion venom

    Directory of Open Access Journals (Sweden)

    A. A. S. Barão

    2008-01-01

    Full Text Available Tityus serrulatus is the most venomous scorpion in Brazil; however, it is not known whether its venom causes any harm to the offspring whose mothers have received it. This study investigates whether the venom of T. serrulatus may lead to deleterious effects in the offspring, when once administered to pregnant rats at a dose that causes moderate envenomation (3mg/kg. The venom effects were studied on the 5th and on the 10th gestation day (GD5 and GD10. The maternal reproductive parameters of the group that received the venom on GD5 showed no alteration. The group that received the venom on GD10 presented an increase in post-implantation losses. In this group, an increase in the liver weight was also observed and one-third of the fetuses presented incomplete ossification of skull bones. None of the groups that received the venom had any visceral malformation or delay in the fetal development of their offspring. The histopathological analysis revealed not only placentas and lungs but also hearts, livers and kidneys in perfect state. Even having caused little effect on the dams, the venom may act in a more incisive way on the offspring, whether by stress generation or by a direct action.

  18. Rays Sting: The Acute Cellular Effects of Ionizing Radiation Exposure.

    Science.gov (United States)

    Franco, A; Ciccarelli, M; Sorriento, D; Napolitano, L; Fiordelisi, A; Trimarco, B; Durante, M; Iaccarino, G

    2016-05-01

    High-precision radiation therapy is a clinical approach that uses the targeted delivery of ionizing radiation, and the subsequent formation of reactive oxygen species (ROS) in high proliferative, radiation sensitive cancers. In particular, in thoracic cancer ratdiation treatments, can not avoid a certain amount of cardiac toxicity. Given the low proliferative rate of cardiac myocytes, research has looked at the effect of radiation on endothelial cells and consequent coronary heart disease as the mechanism of ratdiation induced cardiotoxicity. In fact, little is known concerning the direct effect of radiation on mitochondria dynamis in cardiomyocyte. The main effect of ionizing radiation is the production of ROS and recent works have uncovered that they directly participates to pivotal cell function like mitochondrial quality control. In particular ROS seems to act as check point within the cell to promote either mitochondrial biogenesis and survival or mitochondrial damage and apoptosis. Thus, it appears evident that the functional state of the cell, as well as the expression patterns of molecules involved in mitochondrial metabolism may differently modulate mitochondrial fate in response to radiation induced ROS responses. Different molecules have been described to localize to mitochondria and regulate ROS production in response to stress, in particular GRK2. In this review we will discuss the evidences on the cardiac toxicity induced by X ray radiation on cardiomyocytes with emphasis on the role played by mitochondria dynamism. PMID:27326395

  19. Toxicological impact of cadmium-based quantum dots towards aquatic biota: Effect of natural sunlight exposure.

    Science.gov (United States)

    Silva, B F; Andreani, T; Gavina, A; Vieira, M N; Pereira, C M; Rocha-Santos, T; Pereira, R

    2016-07-01

    Cadmium-based quantum dots (QDs) are increasingly applied in existent and emerging technologies, especially in biological applications due to their exceptional photophysical and functionalization properties. However, they are very toxic compounds due to the high reactive and toxic cadmium core. The present study aimed to determine the toxicity of three different QDs (CdS 380, CdS 480 and CdSeS/ZnS) before and after the exposure of suspensions to sunlight, in order to assess the effect of environmentally relevant irradiation levels in their toxicity, which will act after their release to the environment. Therefore, a battery of ecotoxicological tests was performed with organisms that cover different functional and trophic levels, such as Vibrio fischeri, Raphidocelis subcapitata, Chlorella vulgaris and Daphnia magna. The results showed that core-shell type QDs showed lower toxic effects to V. fischeri in comparison to core type QDs before sunlight exposure. However, after sunlight exposure, there was a decrease of CdS 380 and CdS 480 QD toxicity to bacterium. Also, after sunlight exposure, an effective decrease of CdSeS/ZnS and CdS 480 toxicity for D. magna and R. subcapitata, and an evident increase in CdS 380 QD toxicity, at least for D. magna, were observed. The results of this study suggest that sunlight exposure has an effect in the aggregation and precipitation reactions of larger QDs, causing the degradation of functional groups and formation of larger bulks which may be less prone to photo-oxidation due to their diminished surface area. The same aggregation behaviour after sunlight exposure was observed for bare QDs. These results further emphasize that the shell of QDs seems to make them less harmful to aquatic biota, both under standard environmental conditions and after the exposure to a relevant abiotic factor like sunlight. PMID:27162069

  20. No effect of low-level chronic neonicotinoid exposure on bumblebee learning and fecundity.

    Science.gov (United States)

    Piiroinen, Saija; Botías, Cristina; Nicholls, Elizabeth; Goulson, Dave

    2016-01-01

    In recent years, many pollinators have declined in abundance and diversity worldwide, presenting a potential threat to agricultural productivity, biodiversity and the functioning of natural ecosystems. One of the most debated factors proposed to be contributing to pollinator declines is exposure to pesticides, particularly neonicotinoids, a widely used class of systemic insecticide. Also, newly emerging parasites and diseases, thought to be spread via contact with managed honeybees, may pose threats to other pollinators such as bumblebees. Compared to honeybees, bumblebees could be particularly vulnerable to the effects of stressors due to their smaller and more short-lived colonies. Here, we studied the effect of field-realistic, chronic clothianidin exposure and inoculation with the parasite Nosema ceranae on survival, fecundity, sugar water collection and learning using queenless Bombus terrestris audax microcolonies in the laboratory. Chronic exposure to 1 ppb clothianidin had no significant effects on the traits studied. Interestingly, pesticide exposure in combination with additional stress caused by harnessing bees for Proboscis Extension Response (PER) learning assays, led to an increase in mortality. In contrast to previous findings, the bees did not become infected by N. ceranae after experimental inoculation with the parasite spores, suggesting variability in host resistance or parasite virulence. However, this treatment induced a slight, short-term reduction in sugar water collection, potentially through stimulation of the immune system of the bees. Our results suggest that chronic exposure to 1 ppb clothianidin does not have adverse effects on bumblebee fecundity or learning ability. PMID:27014515

  1. The effect of sublethal short-duration exposure of paraoxon on pregnancy and fetuses in mice

    Directory of Open Access Journals (Sweden)

    Nurulain Syed M.

    2015-01-01

    Full Text Available A convincing number of epidemiological studies have reported on the exposure to and consequences of organophosphorus compounds (OPCs in pregnant women. However, there is still a knowledge gap and paucity of systematic literature from animal studies. This study was undertaken with the hypothesis that short-duration sublethal exposure to OPCs can produce maternal and fetal lethal effects as chronic exposure. This study examineses the teratogenicity and embryotoxicity of paraoxon (POX in mice at a dose that is non-lethal to non-pregnant mothers. Pregnant mice were injected intraperitoneally (i.p. with paraoxon (50 nmol/mouse on the 4th and 5th days of gestation, and the effect of the treatment was assessed on day 18 of gestation. This dose was fatal to pregnant mice in 21% of instances as compared to non-pregnant animals in which 0% mortality was detected, even after daily injection of a similar dose for five days. Significant inhibition of red blood cell acetylcholinesterase (RBC-AChE was observed in pregnant mice as compared to non-pregnant ones; however, no apparent neuronal effect was detected. Of note were fetal weight decrement, pregnancy termination, intrauterine growth retardation and maternal death. We concluded that exposure to even a non-toxic dose might be critical for pregnant mothers, the pregnancy as well as fetuses. In addition, even exposure of short duration can be detrimental and capable of producing profound and fatal effects.

  2. Persistence of Positive Carryover Effects in the Oyster, Saccostrea glomerata, following Transgenerational Exposure to Ocean Acidification.

    Directory of Open Access Journals (Sweden)

    Laura M Parker

    Full Text Available Ocean acidification (OA is predicted to have widespread implications for marine organisms, yet the capacity for species to acclimate or adapt over this century remains unknown. Recent transgenerational studies have shown that for some marine species, exposure of adults to OA can facilitate positive carryover effects to their larval and juvenile offspring that help them to survive in acidifying oceanic conditions. But whether these positive carryover effects can persist into adulthood or the next generation is unknown. Here we tested whether positive carryover effects found in larvae of the oyster, Saccostrea glomerata following transgenerational exposure to elevated CO2, could persist into adulthood and whether subsequent transgenerational exposure of adults to elevated CO2 would facilitate similar adaptive responses in the next generation of larvae and juveniles. Following our previous transgenerational exposure of parental adults and first generation (F1 larvae to ambient (385 μatm and elevated (856 μatm CO2, newly settled F1 juveniles were transferred to the field at ambient CO2 for 14 months, until they reached reproductive maturity. At this time, the F1 adults were returned to the laboratory and the previous transgenerational CO2 exposure was repeated to produce F2 offspring. We found that the capacity of adults to regulate extracellular pH at elevated CO2 was improved if they had a prior history of transgenerational exposure to elevated CO2. In addition, subsequent transgenerational exposure of these adults led to an increase in the resilience of their larval and juvenile offspring. Offspring with a history of transgenerational exposure to elevated CO2 had a lower percentage abnormality, faster development rate, faster shell growth and increased heart rate at elevated CO2 compared with F2 offspring with no prior history of exposure to elevated CO2. Our results suggest that positive carryover effects originating during parental and larval

  3. Physiological Effects of Smoke Exposure on Deciduous and Conifer Tree Species

    Directory of Open Access Journals (Sweden)

    W. John Calder

    2010-01-01

    Full Text Available Smoke from forest fires can persist in the environment for weeks and while there is a substantial amount of literature examining the effects of smoke exposure on seed germination, the effects of smoke on leaf function are nearly uninvestigated. The objective of this study was to compare growth and primary and secondary metabolic responses of deciduous angiosperm and evergreen conifer tree species to short smoke exposure. Twenty minutes of smoke exposure resulted in a greater than 50% reduction in photosynthetic capacity in five of the six species we examined. Impairment of photosynthesis in response to smoke was a function of reductions in stomatal conductance and biochemical limitations. In general, deciduous angiosperm species showed a greater sensitivity than evergreen conifers. While there were significant decreases in photosynthesis and stomatal conductance, smoke had no significant effect on growth or secondary defense compound production in any of the tree species examined.

  4. Evaluation of exposure-response relationships for health effects of microbial bioaerosols - A systematic review.

    Science.gov (United States)

    Walser, Sandra M; Gerstner, Doris G; Brenner, Bernhard; Bünger, Jürgen; Eikmann, Thomas; Janssen, Barbara; Kolb, Stefanie; Kolk, Annette; Nowak, Dennis; Raulf, Monika; Sagunski, Helmut; Sedlmaier, Nadja; Suchenwirth, Roland; Wiesmüller, Gerhard; Wollin, Klaus-Michael; Tesseraux, Irene; Herr, Caroline E W

    2015-10-01

    Studies suggest adverse health effects following exposure to bioaerosols in the environment and in particular at workplaces. However, there is still a lack of health-related exposure limits based on toxicological or epidemiological studies from environmental health or from the working environment. The aim of this study was to derive health-based exposure limits for bioaerosols that can protect the general population as group "at risk" via environmental exposure using analysis of peer-reviewed studies related to occupational medicine, indoor air and environmental health. The derivation of exposure limits should be conducted by the members of a bioaerosol expert panel according to established toxicological criteria. A systematic review was performed in Medline (PubMed) including studies containing both data on exposure measurements and observed health outcomes. In addition, literature recommended by the experts was considered. A comprehensive search strategy was generated and resulted in a total of n=1569 studies in combination with the literature recommendations. Subsequently, abstracts were screened using defined exclusion criteria yielding a final number of n=44 studies. A standardized extraction sheet was used to combine data on health effects and exposure to different bioaerosols. After full-text screening and extraction according to the defined exclusion criteria n=20 studies were selected all related to occupational exposures comprising the working areas wood processing, farming, waste processing and others. These studies were analyzed in collaboration with the bioaerosol expert network in terms of suitability for derivation of health-related exposure limits. The bioaerosol expert network concluded that none of the analyzed studies provided suitable dose-response relationships for derivation of exposure limits. The main reasons were: (1) lack of studies with valid dose-response data; (2) diversity of employed measuring methods for microorganisms and bioaerosol

  5. Effects of exposure to slate dust in North Wales.

    OpenAIRE

    Glover, J. R.; Bevan, C; Cotes, J E; Elwood, P C; Hodges, N. G.; Kell, R L; Lowe, C. R.; McDermott, M; Oldham, P D

    1980-01-01

    In a study of slate workers in four areas in North Wales 725 workers and ex-workers who had been exposed to slate and to no other dust were seen, together with 530 men from the same area who had never been exposed to any dust. Evidence of pneumoconiosis was found in one-third of the slate workers, and 10% had degrees of pneumoconiosis that would attract compensation (category 2 or higher). The prevalence of respiratory symptoms was high, and there was evidence of an effect of both simple and ...

  6. Effects of silver nanoparticles exposure in the mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Gomes, Tânia; Pereira, Catarina G; Cardoso, Cátia; Sousa, Vânia Serrão; Teixeira, Margarida Ribau; Pinheiro, José P; Bebianno, Maria João

    2014-10-01

    Silver nanoparticles (Ag NPs) have emerged as one of the most commonly used NPs in a wide range of industrial and commercial applications. This has caused increasing concern about their fate in the environment as well as uptake and potential toxicity towards aquatic organisms. Accordingly, mussels Mytilus galloprovincialis were exposed to 10 μg L(-1) of Ag NPs and ionic silver (Ag+) for 15 days, and biomarkers of oxidative stress and metal accumulation were determined. Accumulation results show that both Ag NPs and Ag+ accumulated in both gills and digestive glands. Antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) were activated by Ag NPs and Ag+, showing different antioxidant patterns in both gills and digestive glands. Moreover, metallothionein was inducted in gills, directly related to Ag accumulation, while in the digestive glands only a small fraction of Ag seems to be associated with this protein. Lipid peroxidation was higher in gills exposed to Ag NPs, whereas in the digestive glands only Ag+ induced lipid peroxidation. Ag NPs and Ag+ cause oxidative stress with distinct modes of action and it's not clear if for Ag NPs the observed effects are attributed to free Ag+ ions associated with the nanoparticle effect.

  7. Biological effects of short-term, high-concentration exposure to methyl isocyanate. I. Study objectives and inhalation exposure design

    Energy Technology Data Exchange (ETDEWEB)

    Dodd, D.E.; Frank, F.R.; Fowler, E.H.; Troup, C.M.; Milton, R.M.

    1987-06-01

    Early reports from India indicated that humans were dying within minutes to a few hours from exposure to methyl isocyanate (MIC). Attempts to explain the cause(s) of these rapid mortalities is where Union Carbide Corporation concentrated its post-Bhopal toxicologic investigations. The MIC studies involving rats and guinea pigs focused primarily on the consequences of acute pulmonary damage. All MIC inhalation exposures were acute, of short duration (mainly 15 min), and high in concentration. MIC vapors were statically generated in a double chamber exposure design. Precautionary measures taken during exposures are discussed. Guinea pigs were more susceptible than rats to MIC exposure-related early mortality. A greater than one order of magnitude difference was observed between an MIC concentration that caused no early mortality in rats (3506 ppm) and an MIC concentration that caused partial (6%) early mortality in guinea pigs (225 ppm) for exposures of 10 to 15 min duration. For both species, the most noteworthy clinical signs during exposure were lacrimation, blepharospasm, and mouth breathing. Fifteen minute LC/sub 50/ tests with 14-day postexposure follow-up were conducted, and the LC/sub 50/ (95% confidence limit) values were 171 (114-256) ppm for rats and 112 (61-204) ppm for guinea pigs. Target exposure concentrations for the toxicologic investigations of MIC-induced early mortality were established. A short summary of pertinent results of Union Carbide Corporation's post-Bhopal toxicologic investigations is presented.

  8. Renal and blood pressure effects from environmental cadmium exposure in Thai children

    Energy Technology Data Exchange (ETDEWEB)

    Swaddiwudhipong, Witaya, E-mail: swaddi@hotmail.com [Department of Community and Social Medicine, Mae Sot General Hospital, Tak 63110 (Thailand); Mahasakpan, Pranee [Department of Community and Social Medicine, Mae Sot General Hospital, Tak 63110 (Thailand); Jeekeeree, Wanpen [Department of Medical Technology, Mae Sot General Hospital, Tak 63110 (Thailand); Funkhiew, Thippawan [Department of Community and Social Medicine, Mae Sot General Hospital, Tak 63110 (Thailand); Sanjum, Rungaroon; Apiwatpaiboon, Thitikarn [Department of Medical Technology, Mae Sot General Hospital, Tak 63110 (Thailand); Phopueng, Ittipol [Department of Community and Social Medicine, Mae Sot General Hospital, Tak 63110 (Thailand)

    2015-01-15

    Very few studies have shown renal and blood pressure effects from environmental cadmium exposure in children. This population study examined associations between urinary cadmium excretion, a good biomarker of long-term cadmium exposure, and renal dysfunctions and blood pressure in environmentally exposed Thai children. Renal functions including urinary excretion of β{sub 2}-microglobulin, calcium (early renal effects), and total protein (late renal effect), and blood pressure were measured in 594 primary school children. Of the children studied, 19.0% had urinary cadmium ≥1 μg/g creatinine. The prevalence of urinary cadmium ≥1 μg/g creatinine was significantly higher in girls and in those consuming rice grown in cadmium-contaminated areas. The geometric mean levels of urinary β{sub 2}-microglobulin, calcium, and total protein significantly increased with increasing tertiles of urinary cadmium. The analysis did not show increased blood pressure with increasing tertiles of urinary cadmium. After adjusting for age, sex, and blood lead levels, the analysis showed significant positive associations between urinary cadmium and urinary β{sub 2}-microglobulin and urinary calcium, but not urinary total protein nor blood pressure. Our findings provide evidence that environmental cadmium exposure can affect renal functions in children. A follow-up study is essential to assess the clinical significance and progress of renal effects in these children. - Highlights: • Few studies show renal effects from environmental cadmium exposure in children. • We report renal and blood pressure effects from cadmium exposure in Thai children. • Urinary β{sub 2}-microglobulin and calcium increased with increasing urinary cadmium. • The study found no association between urinary cadmium levels and blood pressure. • Environmental cadmium exposure can affect renal functions in children.

  9. Renal and blood pressure effects from environmental cadmium exposure in Thai children

    International Nuclear Information System (INIS)

    Very few studies have shown renal and blood pressure effects from environmental cadmium exposure in children. This population study examined associations between urinary cadmium excretion, a good biomarker of long-term cadmium exposure, and renal dysfunctions and blood pressure in environmentally exposed Thai children. Renal functions including urinary excretion of β2-microglobulin, calcium (early renal effects), and total protein (late renal effect), and blood pressure were measured in 594 primary school children. Of the children studied, 19.0% had urinary cadmium ≥1 μg/g creatinine. The prevalence of urinary cadmium ≥1 μg/g creatinine was significantly higher in girls and in those consuming rice grown in cadmium-contaminated areas. The geometric mean levels of urinary β2-microglobulin, calcium, and total protein significantly increased with increasing tertiles of urinary cadmium. The analysis did not show increased blood pressure with increasing tertiles of urinary cadmium. After adjusting for age, sex, and blood lead levels, the analysis showed significant positive associations between urinary cadmium and urinary β2-microglobulin and urinary calcium, but not urinary total protein nor blood pressure. Our findings provide evidence that environmental cadmium exposure can affect renal functions in children. A follow-up study is essential to assess the clinical significance and progress of renal effects in these children. - Highlights: • Few studies show renal effects from environmental cadmium exposure in children. • We report renal and blood pressure effects from cadmium exposure in Thai children. • Urinary β2-microglobulin and calcium increased with increasing urinary cadmium. • The study found no association between urinary cadmium levels and blood pressure. • Environmental cadmium exposure can affect renal functions in children

  10. Moderating the Effects of Childhood Exposure to Intimate Partner Violence: The Roles of Parenting Characteristics and Adolescent Peer Support

    Science.gov (United States)

    Tajima, Emiko A.; Herrenkohl, Todd I.; Moylan, Carrie A.; Derr, Amelia S.

    2011-01-01

    We investigate parenting characteristics and adolescent peer support as potential moderators of the effects of childhood exposure to intimate partner violence (IPV) on adolescent outcomes. Lehigh Longitudinal Study (N = 416) data include parent and adolescent reports of childhood IPV exposure. Exposure to IPV predicted nearly all adverse outcomes…

  11. Effect of Exposure to Electrical Discharge on Transformer Oil Properties

    Institute of Scientific and Technical Information of China (English)

    J. S. N'Cho; I. Fofana; T. Aka-Ngnui; A. Beroual

    2011-01-01

    Petroleum based oils, the so-called mineral oils, are used for impregnating solid insulations or filling products of very large number of electric materials: transformers, reactors, cables, bushings, circuit breakers, tap changers, etc. In these equipments, oil is exposed to electrical stress and may experience electrical discharges under certain circumstances. Since the electrical stress is unavoidable in power equipments, the ability of oil to resist decomposition under electrical stress is of great importance for the safety of these devices. Electrical stress together with heat and moisture, in the presence of oxygen, oxidises the oil producing free radicals, acids and sludge that are deleterious to the transformer. In this paper, the effect of electrical discharges on oil properties is reported. The results indicate that quality of oil is considerably affected with increasing voltage stress. Comparing oil properties before and after voltage application allows assessing the outcome of random secondary chemical reactions between large oil born free radicals.

  12. Chronic occupational exposure to asbestos: more than medical effects

    Energy Technology Data Exchange (ETDEWEB)

    Lebovits, A.H.; Byrne, M.; Bernstein, J.; Strain, J.J.

    1988-01-01

    One hundred and twenty-nine workers chronically exposed to asbestos were interviewed regarding their perceived health status and concerns, their health behaviors, particularly their smoking behavior, and their psychologic well-being. In contrast to a non-exposed comparison group of postal workers, asbestos workers exhibited significantly elevated levels of somatic concern (P less than .03), and significantly lower levels of mental health functioning only when experiencing high levels of stress (P less than .01). Despite feeling significantly more susceptible to developing cancer (P less than .0001), 34% of asbestos workers were cigarette smokers (compared to 32% of the postal group) and long-term mask usage was minimal. Asbestos workers' increased sensitivity to stress and changes in health status along with the lack of adaptation of health-promotive behaviors indicate the need for interventions to attend to the psychologic effects of increased risk status.

  13. A Review of Cognitive and Behavioral Effects of Increased Carbon Dioxide Exposure in Humans

    Science.gov (United States)

    Stankovic, Aleksandra; Alexander, David; Oman, Charles M.; Schneiderman, Jason

    2016-01-01

    Existing research has reliably demonstrated the respiratory and cardiovascular effects of carbon dioxide (CO2) inhalation at moderately increased levels, with documented physiological changes to heart rate, blood pressure, tissue pH, and blood solubility (for a review of the human health risks of acute elevated CO2 exposure, see Rice, 2004). Studies of indoor air quality have linked increased levels of ambient CO2 with physiological symptoms such as headache, fatigue, and sore throat (Apte et al., 2000; Seppanen et al., 1999; Wargocki et al., 2000). High levels of CO2 (35%) have reliably resulted in activation of the hypothalamic-pituitary-adrenocortical (HPA) axis and subjective anxiety responses in healthy individuals (Argyropoulos et al., 2002), as well as panic attack-like symptoms (Colasanti et al., 2008; Griez et al., 2007) and experiences of physiological stress (Consolazio & Fisher, 1947; Kaye et al., 2004). While significant neurological findings correspond to high levels of CO2 exposure, less clinically significant cognitive effects may occur at a much lower level. These cognitive changes and the exposure thresholds at which they occur are less well established than their physiological counterparts; this paper, therefore, reviews the existing literature on the cognitive, neurological, and psychomotor effects of increased CO2 exposure, with the objective of identifying research areas in which further investigation remains necessary. In particular, this investigation is motivated by the chronic exposure to elevated ambient CO2 concentrations experienced by astronauts aboard the International Space Station (ISS), and the CO2 exposure-related symptoms that have been reported by astronauts on orbit (James, 2007; Law & Watkins, 2009). Such exposure may negatively affect crew health and operations, including mission safety and the successful completion of scientific goals.

  14. Effects of prior exposure on music liking and recognition in patients with temporal lobe lesions.

    Science.gov (United States)

    Samson, Séverine; Peretz, Isabelle

    2005-12-01

    Prior exposure to music typically increases liking. This manifestation of implicit memory can be dissociated from explicit memory recognition. To examine the contribution of the medial temporal lobe to musical preference and recognition, we tested patients with either left (LTL) or right (RTL) temporal lobe lesions as well as normal control (NC) participants using the procedure of Peretz et al. The results in the affect task showed that NC and LTL participants preferred the studied over nonstudied melodies, thereby demonstrating an implicit exposure effect on liking judgments, whereas RTL patients failed to exhibit this effect. Explicit recognition was impaired in both LTL and RTL patients as compared to NC participants. On the basis of these findings, we suggest that RTL structures play a critical role in the formation of melody representations that support both priming and memory recognition, whereas LTL structures are more involved in the explicit retrieval of melodies. Furthermore, we were able to test an amnesic patient (PC) with bilateral lesions of the temporal lobe. In this case, the exposure effect on liking was also absent. However, repeated exposure to melodies was found to enhance both liking and recognition judgments. This remarkable sparing of memory observed through melody repetition suggests that extensive exposure may assist both implicit and explicit memory in the presence of global amnesia. PMID:16597796

  15. The effects of multiple UV exposures on HIV-LTR (long terminal repeat) expression

    International Nuclear Information System (INIS)

    Previous studies have shown that cellular stress agents such as UV radiation induce transcription from the long terminal repeat (LTR) of the human immunodeficiency virus (HIV). Using HeLa cells stably transfected with the HIV-LTR sequence, which transcriptionally drives the chloramphenicol acetyl transferase (CAT) reporter gene, we examined the effects of multiple exposures to UVC (254 nm) on HIV-LTR-CAT expression. Low doses (≤ 5 J m-2) had no effect on CAT expression, but up to 29-fold induction was observed with 10 J m-2 when cells were harvested 48 h after completion of the exposure. Little difference was noted in induction levels when cells were exposed to one 25 J m-2 dose, viable cells were harvested at 24 h, 48 h or 72 h, and cell lysates were assayed for CAT expression. Two sequential 12.5 J m-2 exposures, given 24 h apart, resulted in an additive effect on CAT expression; these two exposures produced CAT activity equivalent to that induced following a single 25 J m-2 dose. Our data suggest that HIV-LTR requires a specific threshold UV dose in order to elicit induction; a maximal induction dose is also evident; exposures higher than this maximal dose contribute no more to HIV-LTR induction in viable cells. (author)

  16. Effects of chronic carbon monoxide exposure on fetal growth and development in mice

    Directory of Open Access Journals (Sweden)

    Venditti Carolina C

    2011-12-01

    Full Text Available Abstract Background Carbon monoxide (CO is produced endogenously, and can also be acquired from many exogenous sources: ie. cigarette smoking, automobile exhaust. Although toxic at high levels, low level production or exposure lends to normal physiologic functions: smooth muscle cell relaxation, control of vascular tone, platelet aggregation, anti- inflammatory and anti-apoptotic events. In pregnancy, it is unclear at what level maternal CO exposure becomes toxic to the fetus. In this study, we hypothesized that CO would be embryotoxic, and we sought to determine at what level of chronic CO exposure in pregnancy embryo/fetotoxic effects are observed. Methods Pregnant CD1 mice were exposed to continuous levels of CO (0 to 400 ppm from conception to gestation day 17. The effect on fetal/placental growth and development, and fetal/maternal CO concentrations were determined. Results Maternal and fetal CO blood concentrations ranged from 1.12- 15.6 percent carboxyhemoglobin (%COHb and 1.0- 28.6%COHb, respectively. No significant difference was observed in placental histological morphology or in placental mass with any CO exposure. At 400 ppm CO vs. control, decreased litter size and fetal mass (p Conclusions Exposure to levels at or below 300 ppm CO throughout pregnancy has little demonstrable effect on fetal growth and development in the mouse.

  17. Investigating the association of cardiovascular effects with personal exposure to particle components and sources

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chang-fu, E-mail: changfu@ntu.edu.tw [Department of Public Health, National Taiwan University, Taipei 100, Taiwan (China); Institute of Environmental Health, National Taiwan University, Taipei 100, Taiwan (China); Institute of Occupational Medicine and Industrial Hygiene, Taipei 100, Taiwan (China); Li, Ya-Ru; Kuo, I-Chun [Institute of Environmental Health, National Taiwan University, Taipei 100, Taiwan (China); Hsu, Shih-Chieh [Research Center for Environmental Changes, Academia Sinica, Taipei 115, Taiwan (China); Lin, Lian-Yu; Su, Ta-Chen [Department of Internal Medicine, National Taiwan University Hospital, Taipei 100, Taiwan (China)

    2012-08-01

    Background: Few studies included information on components and sources when exploring the cardiovascular health effects from personal exposure to particulate matters (PM). We previously reported that exposure to PM between 1.0 and 2.5 {mu}m (PM{sub 2.5-1}) was associated with increased cardio-ankle vascular index (CAVI, an arterial stiffness index), while exposure to PM smaller than 0.25 {mu}m (PM{sub 0.25}) decreased the heart rate variability (HRV) indices. The purpose of this study was to investigate the association between PM elements and cardiovascular health effects and identify responsible sources. Methods: In a panel study of seventeen mail carriers, the subjects were followed for 5-6 days while delivering mail outdoors. Personal filter samples of PM{sub 2.5-1} and PM{sub 0.25} were analyzed for their elemental concentrations. The source-specific exposures were further estimated by using absolute principal factor analysis. We analyzed the component- and source-specific health effects on HRV indices and CAVI using mixed models. Results: Several elements in PM{sub 2.5-1} (e.g., cadmium and strontium) were associated with the CAVI. Subsequent analyses showed that an interquartile range increase in exposure to PM from regional sources was significantly associated with a 3.28% increase in CAVI (95% confidence interval (CI), 1.47%-5.13%). This significant effect remained (3.35%, CI: 1.62%-5.11%) after controlling for the ozone exposures. For exposures to PM{sub 0.25}, manganese, calcium, nickel, and chromium were associated with the CAVI and/or the HRV indices. Conclusions: Our study suggests that PM{sub 2.5-1} and PM{sub 0.25} components may be associated with different cardiovascular effects. Health risks from exposure to PM from sources other than vehicle exhaust should not be underappreciated. - Highlights: Black-Right-Pointing-Pointer Increased arterial stiffness was related to the components in particles between 1.0 and 2.5 {mu}m. Black

  18. Mapping the spatio-temporal risk of lead exposure in apex species for more effective mitigation.

    Science.gov (United States)

    Mateo-Tomás, Patricia; Olea, Pedro P; Jiménez-Moreno, María; Camarero, Pablo R; Sánchez-Barbudo, Inés S; Rodríguez Martín-Doimeadios, Rosa C; Mateo, Rafael

    2016-07-27

    Effective mitigation of the risks posed by environmental contaminants for ecosystem integrity and human health requires knowing their sources and spatio-temporal distribution. We analysed the exposure to lead (Pb) in griffon vulture Gyps fulvus-an apex species valuable as biomonitoring sentinel. We determined vultures' lead exposure and its main sources by combining isotope signatures and modelling analyses of 691 bird blood samples collected over 5 years. We made yearlong spatially explicit predictions of the species risk of lead exposure. Our results highlight elevated lead exposure of griffon vultures (i.e. 44.9% of the studied population, approximately 15% of the European, showed lead blood levels more than 200 ng ml(-1)) partly owing to environmental lead (e.g. geological sources). These exposures to environmental lead of geological sources increased in those vultures exposed to point sources (e.g. lead-based ammunition). These spatial models and pollutant risk maps are powerful tools that identify areas of wildlife exposure to potentially harmful sources of lead that could affect ecosystem and human health. PMID:27466455

  19. Effects of whole body exposure to electromagnetic field on normal and osteoporotic bone metabolism in rats

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, S.; Iida, H. [National Inst. of Radiological Sciences, Chiba (Japan)

    2000-05-01

    The biological effects of the exposure to the electromagnetic field particularly on bone metabolism in growing rats that were ovariectomized (OVX) and fed different calcium diets were determined. Female Wistar rats, 8 weeks old, were divided into four groups; OVX fed standardized (1.2%) calcium diet (StCa), OVX fed low (0.02%) Ca diet (LCa), no-OVX+StCa and no-OVX+LCa groups. Half of rats in each group were exposed to electromagnetic field (100 mG, 50 Hz). Rats (n=5) in each group were sacrificed 1, 2, and 3 month after the exposure. Analyses of bone and serum were performed. Compared to the corresponding control groups, the body weights in the exposure groups, decreased at each measured point. The bone mineral density in the total and trabecular bone in the tibia and femur decreased 2 month after the exposure. In the histomorphometric measurement using the tibial proximal metaphysis at 3 months later, the decreases in bone volume, bone formation rate, eroded surface and depth, and the increases in trabecular separation were observed in the exposure groups. The bone fragility (femur) also was observed. Simultaneously the decreases in the weights of adrenal gland and skeletal muscles, and value in serum rat-PTH and BGP were observed. The results indicate that the bone growth and metabolism in the growth process are inhibited and enlarged with low Ca intakes by the long-term exposure in an electromagnetic field in rats. (author)

  20. Effects of whole body exposure to electromagnetic field on normal and osteoporotic bone metabolism in rats

    International Nuclear Information System (INIS)

    The biological effects of the exposure to the electromagnetic field particularly on bone metabolism in growing rats that were ovariectomized (OVX) and fed different calcium diets were determined. Female Wistar rats, 8 weeks old, were divided into four groups; OVX fed standardized (1.2%) calcium diet (StCa), OVX fed low (0.02%) Ca diet (LCa), no-OVX+StCa and no-OVX+LCa groups. Half of rats in each group were exposed to electromagnetic field (100 mG, 50 Hz). Rats (n=5) in each group were sacrificed 1, 2, and 3 month after the exposure. Analyses of bone and serum were performed. Compared to the corresponding control groups, the body weights in the exposure groups, decreased at each measured point. The bone mineral density in the total and trabecular bone in the tibia and femur decreased 2 month after the exposure. In the histomorphometric measurement using the tibial proximal metaphysis at 3 months later, the decreases in bone volume, bone formation rate, eroded surface and depth, and the increases in trabecular separation were observed in the exposure groups. The bone fragility (femur) also was observed. Simultaneously the decreases in the weights of adrenal gland and skeletal muscles, and value in serum rat-PTH and BGP were observed. The results indicate that the bone growth and metabolism in the growth process are inhibited and enlarged with low Ca intakes by the long-term exposure in an electromagnetic field in rats. (author)

  1. Epigenetic effects of prenatal estradiol-17β exposure on the reproductive system of pigs.

    Science.gov (United States)

    Kradolfer, David; Flöter, Veronika L; Bick, Jochen T; Fürst, Rainer W; Rode, Kristina; Brehm, Ralph; Henning, Heiko; Waberski, Dagmar; Bauersachs, Stefan; Ulbrich, Susanne E

    2016-07-15

    There is growing evidence that early life exposure to endocrine disrupting chemicals might increase the risk for certain adult onset diseases, in particular reproductive health problems and hormone dependent cancers. Studies in rodents suggest that perinatal exposure to even low doses of estrogenic substances can cause adverse effects, including epigenetic reprogramming of the prostate and increased formation of precancerous lesions. We analyzed the effects of an in utero exposure to the strongest natural estrogen, estradiol-17β, in a pig model. Two different low and one high dose of estradiol-17β (0.05, 10 and 1000 μg/kg body weight/day) were orally applied to gilts during pregnancy and potential effects on the reproductive system of the offspring were analyzed. No significant effects on sperm vitality parameters and testes size were observed in adult boars. However, prenatal exposure to the high dose decreased absolute, but not relative weight of the testes in prepubertal piglets. RNA sequencing revealed significantly regulated genes of the prepubertal prostate, while testes and uteri were not affected. Notably, we found an increased prostate expression of CCDC80 and a decreased ADH1C expression in the low dose treatment groups. BGN and SPARC, two genes associated with prostate tumor progression, were as well more abundant in exposed animals. Strikingly, the gene body DNA methylation level of BGN was accordingly increased in the high dose group. Thus, while only prenatal exposure to a high dose of estrogen altered testes development and local DNA methylation of the prostate, even low dose exposure had significant effects on gene expression in the prostate of prepubertal piglet offspring. The relevance of these distinct, but subtle transcriptional changes following low dose treatment lacking a clear phenotype calls for further long-term investigations. An epigenetic reprogramming of the pig prostate due to prenatal estrogen cannot be neglected. PMID:27062901

  2. Effects of low arsenic concentration exposure on freshwater fish in the presence of fluvial biofilms.

    Science.gov (United States)

    Tuulaikhuu, Baigal-Amar; Bonet, Berta; Guasch, Helena

    2016-02-15

    Arsenic (As) is a highly toxic element and its carcinogenic effect on living organisms is well known. However, predicting real effects in the environment requires an ecological approach since toxicity is influenced by many environmental and biological factors. The purpose of this paper was to evaluate if environmentally-realistic arsenic exposure causes toxicity to fish. An experiment with four different treatments (control (C), biofilm (B), arsenic (+As) and biofilm with arsenic (B+As)) was conducted and each one included sediment to enhance environmental realism, allowing the testing of the interactive effects of biofilm and arsenic on the toxicity to fish. Average arsenic exposure to Eastern mosquitofish (Gambusia holbrooki) was 40.5 ± 7.5 μg/L for +As treatment and 34.4 ± 1.4 μg/L for B+As treatment for 56 days. Fish were affected directly and indirectly by this low arsenic concentration since exposure did not only affect fish but also the function of periphytic biofilms. Arsenic effects on the superoxide dismutase (SOD) and glutathione reductase (GR) activities in the liver of mosquitofish were ameliorated in the presence of biofilms at the beginning of exposure (day 9). Moreover, fish weight gaining was only affected in the treatment without biofilm. After longer exposure (56 days), effects of exposure were clearly seen. Fish showed a marked increase in the catalase (CAT) activity in the liver but the interactive influence of biofilms was not further observed since the arsenic-affected biofilm had lost its role in water purification. Our results highlight the interest and application of incorporating some of the complexity of natural systems in ecotoxicology and support the use of criterion continuous concentration (CCC) for arsenic lower than 150 μg/L and closer to the water quality criteria to protect aquatic life recommended by the Canadian government which is 5 μg As/L.

  3. Effect of alcohol exposure on fetal brain development

    Science.gov (United States)

    Sudheendran, Narendran; Bake, Shameena; Miranda, Rajesh C.; Larin, Kirill V.

    2013-02-01

    Alcohol consumption during pregnancy can be severely damage to the brain development in fetuses. This study investigates the effects of maternal ethanol consumption on brain development in mice embryos. Pregnant mice at gestational day 12.5 were intragastrically gavaged with ethanol (3g/Kg bwt) twice daily for three consecutive days. On gestational day 14.5, fetuses were collected and fixed in 4% paraformaldehyde and imaged using a swept-source optical coherence tomography (SSOCT) system. 3D images of the mice embryo brain were obtained and the volumes of the left and right ventricles of the brain were measured. The average volumes of the left and the right volumes of 5 embryos each alcohol-exposed and control embryos were measured to be 0.35 and 0.15 mm3, respectively. The results suggest that the left and right ventricle volumes of brain are much larger in the alcohol-exposed embryos as compared to control embryos indicating alcohol-induced developmental delay.

  4. Comparative toxicological studies on the effects of internal exposures

    International Nuclear Information System (INIS)

    Age-related changes in bone metabolism of normal beagle dogs, from 3 months to 17 years of age, were examined by morphometric and serum biochemical values. From 3 months to 2 years of age, bone volume (BV/TV) and trabecular thickness (Th. Tb.) in the iliac trabecular bone, labeled with tetracycline and calcein, increased rapidly with an increase of body weight. Mineral apposition rate (MAR) and bone formation rate (BFR, equivalent to bone turnover rate) decreased. The BFR at 3 months was approximately 11 times in males and 15 times in females higher than that at 2 years when bone metabolism was of adult type. From 2 to 10 years of age, BV/TV or Th. Tb. did not remarkably change, whereas both MAR and BFR had a tendency to decrease gradually with age. Parathyroid hormone level increased from 3 months to 17 years. Testosterone level increased up to 2 years and remained almost constant thereafter. Serum osteocalcin, alkaline phosphatase, and phosphorus decreased rapidly up to 2 years, although calcium did not change with age. Effects of swimming (exercise) and lactate calcium on osteoporotic bones in rats were examined. The BV/TV and Th. Tb. increased, but the MAR and BFR were improved to be sustained. These changes were promoted by the administration of calcium and vitamin D3. Toxicological study on DTPA revealed the following results: (1) Both hypocalcemia, following an increase of blood pressure, and heart failure were observed by iv injection of Zn-DTPA, but not observed by iv injection of Ca-DTPA. When DTPA was given orally, Ca-DTPA was more toxic than Zn-DTPA. DTPA toxicity induced dysfunction of the kidney and liver, hemorrhage and congestion in the lamina propria, and vascular expansion of the small intestine. Vascular permeability was also enhanced by either Ca-DTPA or Zn-DTPA. DTPA toxicity was found to be manifested by disturbed cardiovascular system. (Namekawa, K)

  5. Effects of exposure to lead among lead-acid battery factory workers in Sudan.

    Science.gov (United States)

    Awad el Karim, M A; Hamed, A S; Elhaimi, Y A; Osman, Y; el Karim, M A

    1986-01-01

    Health effects of occupational exposure to lead were investigated among 92 exposed workers in lead-acid battery factory and 40 nonexposed workers serving as a control group from an oil mill in Khartoum North industrial area. The two groups were closely similar in age, stature, body weight, and socioeconomic conditions. A highly significant increase (P less than .01) was recorded in blood lead, urinary coproporphyrin, and basophilic stippled red blood cells of the exposed group in comparison to the control group. Central nervous system symptoms (insomnia, fatigue, weakness, and drowsiness) were reported by 50% and other symptoms such as abdominal colic and constipation were reported by 41% of the exposed group. Blue line on the gum was detected only on 2% of the exposed group. Strong associations between exposure to lead and the prevalence of central nervous system symptoms, abdominal colic, and constipation were recorded. Exposure to exceedingly high levels of lead in the working environment causes adverse health effects.

  6. The effect of exposure duration on visual character identification in single, whole and partial report

    DEFF Research Database (Denmark)

    Petersen, Anders; Andersen, Tobias

    2012-01-01

    The psychometric function of single letter identification is typically described as a function of stimulus intensity. However, the effect of stimulus exposure duration on letter identification remains poorly described. This is surprising because the effect of exposure duration has played a central...... role in modelling performance in whole and partial report tasks in which multiple simultaneously presented letters are to be reported (Shibuya & Bundesen, 1988). Therefore, we investigated visual letter identification as a function of exposure duration. On each trial, a single randomly chosen letter (A....... Finally, after insertion into Bundesen’s Theory of Visual Attention (Bundesen, 1990), the same psychometric functions enable closer fits to data from a previous whole and partial report experiment....

  7. Transgenerational effects of adolescent nicotine exposure in rats: Evidence for cognitive deficits in adult female offspring.

    Science.gov (United States)

    Renaud, Samantha M; Fountain, Stephen B

    2016-01-01

    This study investigated whether adolescent nicotine exposure in one generation of rats would impair the cognitive capacity of a subsequent generation. Male and female rats in the parental F0 generation were given twice-daily i.p. injections of either 1.0mg/kg nicotine or an equivalent volume of saline for 35days during adolescence on postnatal days 25-59 (P25-59). After reaching adulthood, male and female nicotine-exposed rats were paired for breeding as were male and female saline control rats. Only female offspring were used in this experiment. Half of the offspring of F0 nicotine-exposed breeders and half of the offspring of F0 saline control rats received twice-daily i.p. injections of 1.0mg/kg nicotine during adolescence on P25-59. The remainder of the rats received twice-daily saline injections for the same period. To evaluate transgenerational effects of nicotine exposure on complex cognitive learning abilities, F1 generation rats were trained to perform a highly structured serial pattern in a serial multiple choice (SMC) task. Beginning on P95, rats in the F1 generation were given either 4days of massed training (20patterns/day) followed by spaced training (10 patterns/day) or only spaced training. Transgenerational effects of adolescent nicotine exposure were observed as greater difficulty in learning a "violation element" of the pattern, which indicated that rats were impaired in the ability to encode and remember multiple sequential elements as compound or configural cues. The results indicated that for rats that received massed training, F1 generation rats with adolescent nicotine exposure whose F0 generation parents also experienced adolescent nicotine exposure showed poorer learning of the violation element than rats that experienced adolescent nicotine exposure only in the F1 generation. Thus, adolescent nicotine exposure in one generation of rats produced a cognitive impairment in the next generation.

  8. The effect of intimate exposure to alcohol abuse on the acquisition of knowledge about drinking.

    Science.gov (United States)

    Rainer, J P

    1994-01-01

    This study explored how an alcohol education program might be structured to effectively educate college students about the consequences of alcohol use. The primary hypothesis tested stated that individuals would vary significantly in the amount of knowledge learned from a structured alcohol education workshop, based on the degree of familial or social exposure s/he has had to alcohol abuse. Social learning variables of locus of control, dogmatism, and expectancy for risk were tested for interaction with degree of exposure, to determine their influence on learning. A pretest-posttest control group was employed with a sample of 66 undergraduate college students. A four hour alcohol education program was administered to teach cognitive information and fact about alcohol, with a goal of facilitating responsible use/nonuse of alcohol. The Student Drinking Questionnaire measured acquisition of knowledge. The Adult Nowicki-Strickland Internal/External Scale measured locus of control, and Schultze's Short Dogmatism Scale measured dogmatism. The researcher developed an instrument for expectancy for risk. Multiple regression analyses yielded prediction equations for the variables under study. For the sample group, results demonstrated that a significant portion of the variance in the residualized posttest scores was accounted for by level of exposure and dogmatism. When the sample was blocked according to intimate or social exposure, dogmatism was the only construct entering the regression equation at a significant level for the intimate exposure group. None of the constructs were able to predict any of the residualized posttest scores for the social exposure group. It was concluded that: (1) Students in the sample learned differentially based on the degree of intimate exposure of alcohol; (2) Dogmatism is a moderating variable with acquisition of knowledge for those intimately exposed to alcohol abuse, but locus of control and expectancy for risk are not; and (3) Further

  9. Thermal Exposure Effects on Properties of Al-Li Alloy Plate Products

    Science.gov (United States)

    Shah, Sandeep; Wells, Douglas; Wagner, John; Babel, Henry

    2002-01-01

    Aluminum-Lithium (AL-Li) alloys offer significant performance benefits for aerospace structural applications due to their higher specific properties compared with conventional aluminum alloys. For example, the application of an Al-Li alloy to the space shuttle external cryogenic fuel tank contributed to the weight savings that enabled successful deployment of International Space Station components. The composition and heat treatment of this alloy were optimized specifically for strength-toughness considerations for an expendable cryogenic tank. Time dependent properties related to reliability, such as thermal stability, fatigue, and corrosion, will be of significant interest when materials are evaluated for a reusable cryotank structure. As most aerospace structural hardware is weight sensitive, a reusable cryotank will be designed to the limits of the materials mechanical properties. Therefore, this effort was designed to establish the effects of thermal exposure on the mechanical properties and microstructure of one relatively production mature alloy and two developmental alloys C458 and L277. Tensile and fracture toughness behavior was evaluated after exposure to temperatures as high as 3oooF for up to IO00 hrs. Microstructural changes were also evaluated to correlate with the observed data trends. The ambient temperature parent metal data showed an increase in strength and reduction in elongation after exposure at lower temperatures. Strength reached a peak with intermediate temperature exposure followed by a decrease at highest exposure temperature. Characterizing the effect of thermal exposure on the properties of Al-Li alloys is important to defining a service limiting temperature, exposure time, and end-of-life properties.

  10. The effects of postnatal alcohol exposure and galantamine on the context pre-exposure facilitation effect and acetylcholine efflux using in vivo microdialysis.

    Science.gov (United States)

    Perkins, Amy E; Fadel, Jim R; Kelly, Sandra J

    2015-05-01

    Fetal alcohol spectrum disorders (FASD) are characterized by damage to multiple brain regions, including the hippocampus, which is involved in learning and memory. The acetylcholine neurotransmitter system provides major input to the hippocampus and is a possible target of developmental alcohol exposure. Alcohol (3.0 g/kg/day) was administered via intubation to male rat pups (postnatal day [PD] 2-10; ethanol-treated [ET]). Controls received a sham intubation (IC) or no treatment (NC). Acetylcholine efflux was measured using in vivo microdialysis (PD 32-35). ET animals were not different at baseline, but had decreased K(+)/Ca(2+)-induced acetylcholine efflux compared to NC animals and an enhanced acetylcholine response to galantamine (acetylcholinesterase inhibitor; 2.0 mg/kg) compared to both control groups. A separate cohort of animals was tested in the context pre-exposure facilitation effect task (CPFE; PD 30-32) following postnatal alcohol exposure and administration of galantamine (2.0 mg/kg; PD 11-30). Neither chronic galantamine nor postnatal alcohol exposure influenced performance in the CPFE task. Using immunohistochemistry, we found that neither alcohol exposure nor behavioral testing significantly altered the density of vesicular acetylcholine transporter or alpha7 nicotinic acetylcholine receptor in the ventral hippocampus (CA1). In the medial septum, the average number of choline acetyltransferase (ChAT+) cells was increased in ET animals that displayed the context-shock association; there were no changes in IC and NC animals that learned the context-shock association or in any animals that were in the control task that entailed no learning. Taken together, these results indicate that the hippocampal acetylcholine system is significantly disrupted under conditions of pharmacological manipulations (e.g., galantamine) in alcohol-exposed animals. Furthermore, ChAT was up‑regulated in ET animals that learned the CPFE, which may account for their ability

  11. Imputability of health effects to low-dose radiation exposure situations

    International Nuclear Information System (INIS)

    The key note address is aimed to discuss a crucial issue in nuclear law: whether or not late health effects of stochastic nature, such as radio-induced cancer or hereditable effects, are attributable to radiation exposure situations delivering relatively low radiation doses and, therefore, whether such effects are imputable to those responsible of such situations. The term low dose is used in the presentation when referring to doses similar to natural background doses. (author)

  12. Offspring of prenatal IV nicotine exposure exhibit increased sensitivity to the reinforcing effects of methamphetamine

    Directory of Open Access Journals (Sweden)

    Steven Brown Harrod

    2012-06-01

    Full Text Available Maternal smoking during pregnancy is associated with increased substance abuse in offspring. Preclinical research shows that in utero exposure to nicotine, the primary psychoactive compound in tobacco smoke, influences the neurodevelopment of reward systems and alters motivated behavior in offspring. The present study determined if prenatal nicotine (PN exposure altered the sensitivity to the reinforcing and aversive effects of methamphetamine (METH in offspring using a low dose, intravenous (IV exposure method. Pregnant dams were administered nicotine (0.05 mg/kg/injection or prenatal saline (PS 3×/day on gestational days 8-21, and adult offspring were tested using METH self-administration (experiment 1 or METH-induced conditioned taste aversion (CTA; experiment 2 procedures. For METH self-administration, animals were trained to respond for IV METH (0.05 mg/kg/injection; fixed-ratio 3 and they were tested on varying doses the reinforcer (0.0005-1.0 mg/kg/injection. For METH CTA, rats received three saccharin and METH pairings (0, 0.3, or 0.5 mg/kg, sc followed by fourteen daily extinction trials. Experiment 1: PN and PS animals exhibited inverted U-shaped dose-response curves; however, the PN animal’s curve was shifted to the left, suggesting PN animals were more sensitive to the reinforcing effects of METH. Experiment 2: METH CTA was acquired in a dose-dependent manner and the factor of PN exposure was not related to the acquisition or extinction of METH-induced CTA. There were no sex differences in either experiment. These results indicate that adult offspring of IV PN exposure exhibited altered motivation for the reinforcing effects of METH. This suggests that PN exposure, via maternal smoking, will alter the reinforcing effects of METH during later stages of development, and furthermore, will influence substance use vulnerability in adult human offspring.

  13. The mere exposure effect depends on an odour’s initial pleasantness

    Directory of Open Access Journals (Sweden)

    Sylvain eDelplanque

    2015-07-01

    Full Text Available The mere exposure phenomenon refers to improvement of one’s attitude toward an a priori neutral stimulus after its repeated exposure. The extent to which such a phenomenon influences evaluation of a priori emotional stimuli remains under-investigated. Here we investigated this question by presenting participants with different odours varying in a priori pleasantness during different sessions spaced over time. Participants were requested to report each odour’s pleasantness, intensity, and familiarity. As expected, participants became more familiar with all stimuli after the repetition procedure. However, while neutral and mildly pleasant odours showed an increase in pleasantness ratings, unpleasant and very pleasant odours remained unaffected. Correlational analyses revealed an inverse U-shape between the magnitude of the mere exposure effect and the initial pleasantness of the odour. Consequently, the initial pleasantness of the stimuli appears to modulate the impact of repeated exposures on an individual’s attitude. These data underline the limits of mere exposure effect and are discussed in light of the biological relevance of odours for individual survival.

  14. The mere exposure effect depends on an odor’s initial pleasantness

    Science.gov (United States)

    Delplanque, Sylvain; Coppin, Géraldine; Bloesch, Laurène; Cayeux, Isabelle; Sander, David

    2015-01-01

    The mere exposure phenomenon refers to improvement of one’s attitude toward an a priori neutral stimulus after its repeated exposure. The extent to which such a phenomenon influences evaluation of a priori emotional stimuli remains under-investigated. Here we investigated this question by presenting participants with different odors varying in a priori pleasantness during different sessions spaced over time. Participants were requested to report each odor’s pleasantness, intensity, and familiarity. As expected, participants became more familiar with all stimuli after the repetition procedure. However, while neutral and mildly pleasant odors showed an increase in pleasantness ratings, unpleasant and very pleasant odors remained unaffected. Correlational analyses revealed an inverse U-shape between the magnitude of the mere exposure effect and the initial pleasantness of the odor. Consequently, the initial pleasantness of the stimuli appears to modulate the impact of repeated exposures on an individual’s attitude. These data underline the limits of mere exposure effect and are discussed in light of the biological relevance of odors for individual survival. PMID:26191021

  15. Organophosphate pesticides exposure among farmworkers: pathways and risk of adverse health effects.

    Science.gov (United States)

    Suratman, Suratman; Edwards, John William; Babina, Kateryna

    2015-01-01

    Organophosphate (OP) compounds are the most widely used pesticides with more than 100 OP compounds in use around the world. The high-intensity use of OP pesticides contributes to morbidity and mortality in farmworkers and their families through acute or chronic pesticides-related illnesses. Many factors contributing to adverse health effects have been investigated by researchers to determine pathways of OP-pesticide exposure among farmers in developed and developing countries. Factors like wind/agricultural pesticide drift, mixing and spraying pesticides, use of personal protective equipment (PPE), knowledge, perceptions, washing hands, taking a shower, wearing contaminated clothes, eating, drinking, smoking, and hot weather are common in both groups of countries. Factors including low socioeconomic status areas, workplace conditions, duration of exposure, pesticide safety training, frequency of applying pesticides, spraying against the wind, and reuse of pesticide containers for storage are specific contributors in developing countries, whereas housing conditions, social contextual factors, and mechanical equipment were specific pathways in developed countries. This paper compares existing research in environmental and behavioural exposure modifying factors and biological monitoring between developing and developed countries. The main objective of this review is to explore the current depth of understanding of exposure pathways and factors increasing the risk of exposure potentially leading to adverse health effects specific to each group of countries.

  16. Longitudinal Effects of Embryonic Exposure to Cocaine on Morphology, Cardiovascular Physiology, and Behavior in Zebrafish.

    Science.gov (United States)

    Mersereau, Eric J; Boyle, Cody A; Poitra, Shelby; Espinoza, Ana; Seiler, Joclyn; Longie, Robert; Delvo, Lisa; Szarkowski, Megan; Maliske, Joshua; Chalmers, Sarah; Darland, Diane C; Darland, Tristan

    2016-05-31

    A sizeable portion of the societal drain from cocaine abuse results from the complications of in utero drug exposure. Because of challenges in using humans and mammalian model organisms as test subjects, much debate remains about the impact of in utero cocaine exposure. Zebrafish offer a number of advantages as a model in longitudinal toxicology studies and are quite sensitive physiologically and behaviorally to cocaine. In this study, we have used zebrafish to model the effects of embryonic pre-exposure to cocaine on development and on subsequent cardiovascular physiology and cocaine-induced conditioned place preference (CPP) in longitudinal adults. Larval fish showed a progressive decrease in telencephalic size with increased doses of cocaine. These treated larvae also showed a dose dependent response in heart rate that persisted 24 h after drug cessation. Embryonic cocaine exposure had little effect on overall health of longitudinal adults, but subtle changes in cardiovascular physiology were seen including decreased sensitivity to isoproterenol and increased sensitivity to cocaine. These longitudinal adult fish also showed an embryonic dose-dependent change in CPP behavior, suggesting an increased sensitivity. These studies clearly show that pre-exposure during embryonic development affects subsequent cocaine sensitivity in longitudinal adults.

  17. Longitudinal Effects of Embryonic Exposure to Cocaine on Morphology, Cardiovascular Physiology, and Behavior in Zebrafish

    Directory of Open Access Journals (Sweden)

    Eric J. Mersereau

    2016-05-01

    Full Text Available A sizeable portion of the societal drain from cocaine abuse results from the complications of in utero drug exposure. Because of challenges in using humans and mammalian model organisms as test subjects, much debate remains about the impact of in utero cocaine exposure. Zebrafish offer a number of advantages as a model in longitudinal toxicology studies and are quite sensitive physiologically and behaviorally to cocaine. In this study, we have used zebrafish to model the effects of embryonic pre-exposure to cocaine on development and on subsequent cardiovascular physiology and cocaine-induced conditioned place preference (CPP in longitudinal adults. Larval fish showed a progressive decrease in telencephalic size with increased doses of cocaine. These treated larvae also showed a dose dependent response in heart rate that persisted 24 h after drug cessation. Embryonic cocaine exposure had little effect on overall health of longitudinal adults, but subtle changes in cardiovascular physiology were seen including decreased sensitivity to isoproterenol and increased sensitivity to cocaine. These longitudinal adult fish also showed an embryonic dose-dependent change in CPP behavior, suggesting an increased sensitivity. These studies clearly show that pre-exposure during embryonic development affects subsequent cocaine sensitivity in longitudinal adults.

  18. Lead exposure in Laysan albatross adults and chicks in Hawaii: prevalence, risk factors, and biochemical effects.

    Science.gov (United States)

    Work, T.M.; Smith, M.R.

    1996-01-01

    Prevalence of lead exposure and elevated tissue lead was determined in Laysan albatross (Diomedea immutabilis) in Hawaii. The relationship between lead exposure and proximity to buildings, between elevated blood lead and droopwing status, and elevated liver lead and presence of lead-containing paint chips in the proventriculus in albatross chicks was also examined. Finally, the effects of lead on the enzyme δ-amino-levulinic acid dehydratase (ALAD) was determined. There was a significant association between lead exposure or elevated tissue lead and proximity to buildings in albatross chicks and presence of lead paint chips in the proventriculus and elevated liver lead in carcasses. Although there was a significant association between elevated blood lead and droopwing chicks, there were notable exceptions. Prevalence of elevated tissue lead in albatross chicks was highest on Sand Island Midway and much less so on Kauai and virtually nonexistent in other areas. Prevalence of lead exposure decreased as numbers of buildings to which chicks were exposed on a given island decreased. Laysan albatross adults had minimal to no lead exposure. There was a significant negative correlation between blood lead concentration and ALAD activity in chicks. Based on ALAD activity, 0.03-0.05 μg/ml was the no effect range for blood lead in albatross chicks.

  19. Effect of sorption on exposures to organic gases from environmental tobacco smoke (ETS)

    Energy Technology Data Exchange (ETDEWEB)

    Singer, B.C.; Hodgson, A.T.; Nazaroff, W.W.

    2002-01-01

    The effects of sorption processes on dynamic ETS organic gas concentrations and potential exposures were studied in a carpeted and furnished 50-m{sup 3} room ventilated at 0.6 h{sup -1}. Ten cigarettes were machine-smoked on six of every seven days over four weeks. Concentrations of ETS-specific tracers and regulated toxic compounds were quantified during daily smoking, post-smoking and background periods. Potential exposures were calculated by period and day. Large sorption effects were observed for the widely used tracers 3-ethenylpyridine and nicotine, and for several toxic compounds including naphthalene and cresol isomers. Short-term adsorption to indoor surfaces reduced concentrations and potential exposures during smoking, while later reemission increased concentrations and exposures hours after smoking ended. Concentrations during nonsmoking periods rose from day to day over the first few weeks, presumably from increased reemission associated with increased sorbed mass concentrations. For sorbing compounds, more than half of daily potential exposures occurred during nonsmoking periods.

  20. Health effects of occupational exposure to static magnetic field in a chloralkali plant

    Directory of Open Access Journals (Sweden)

    Choobineh A

    2005-01-01

    Full Text Available A cross-sectional study was conducted to determine if long-term exposure to static magnetic fields could be related to findings of medical examination. Health data was obtained for 20 workers who spent a major period of their working time in the magnetic field produced by direct current through large electric cells. The data was compared to that of control group of 21 workers. Intensity of magnetic flux density was measured in the Chloralkali plant and the TWA exposure to magnetic field was determined for each job classification. Maximum and minimum intensities were found to be 16.99 and 0.49 mT, respectively, which were well below the recommended level. Maximum TWA exposure to magnetic field was equal to 47.59 mT that was less than the acceptable level. The results of clinical examinations and blood tests revealed that there was no significant difference between the two groups. The only effects which were found to be related to exposure to the magnetic field were nervousness and fatigue. Studying a larger sample size may contribute to detect any health effects of occupational exposure to static magnetic field in industrial settings.

  1. Effects of methylmercury and alcohol exposure in Drosophila melanogaster: Potential risks in neurodevelopmental disorders.

    Science.gov (United States)

    Chauhan, Ved; Chauhan, Abha

    2016-06-01

    Extensive evidence suggests the role of oxidative stress in autism and other neurodevelopmental disorders. In this study, we investigated whether methylmercury (MeHg) and/or alcohol exposure has deleterious effects in Drosophila melanogaster (fruit flies). A diet containing different concentrations of MeHg in Drosophila induced free radical generation and increased lipid peroxidation (markers of oxidative stress) in a dose-dependent manner. This effect of MeHg on oxidative stress was enhanced by further exposure to alcohol. It was observed that alcohol alone could also induce free radical generation in flies. After alcohol exposure, MeHg did not affect the immobilization of flies, but it increased the recovery time in a concentration-dependent manner. MeHg significantly inhibited the activity of alcohol dehydrogenase (ADH) in a dose-dependent manner. Linear regression analysis showed a significant negative correlation between ADH activity and recovery time upon alcohol exposure in the flies fed a diet with MeHg. This relationship between ADH activity and recovery time after alcohol exposure was confirmed by adding 4-methyl pyrazole (an inhibitor of ADH) to the diet for the flies. These results suggest that consumption of alcohol by pregnant mothers who are exposed to MeHg may lead to increased oxidative stress and to increased length of time for alcohol clearance, which may have a direct impact on the development of the fetus, thereby increasing the risk of neurodevelopmental disorders. PMID:27151262

  2. Longitudinal Effects of Embryonic Exposure to Cocaine on Morphology, Cardiovascular Physiology, and Behavior in Zebrafish.

    Science.gov (United States)

    Mersereau, Eric J; Boyle, Cody A; Poitra, Shelby; Espinoza, Ana; Seiler, Joclyn; Longie, Robert; Delvo, Lisa; Szarkowski, Megan; Maliske, Joshua; Chalmers, Sarah; Darland, Diane C; Darland, Tristan

    2016-01-01

    A sizeable portion of the societal drain from cocaine abuse results from the complications of in utero drug exposure. Because of challenges in using humans and mammalian model organisms as test subjects, much debate remains about the impact of in utero cocaine exposure. Zebrafish offer a number of advantages as a model in longitudinal toxicology studies and are quite sensitive physiologically and behaviorally to cocaine. In this study, we have used zebrafish to model the effects of embryonic pre-exposure to cocaine on development and on subsequent cardiovascular physiology and cocaine-induced conditioned place preference (CPP) in longitudinal adults. Larval fish showed a progressive decrease in telencephalic size with increased doses of cocaine. These treated larvae also showed a dose dependent response in heart rate that persisted 24 h after drug cessation. Embryonic cocaine exposure had little effect on overall health of longitudinal adults, but subtle changes in cardiovascular physiology were seen including decreased sensitivity to isoproterenol and increased sensitivity to cocaine. These longitudinal adult fish also showed an embryonic dose-dependent change in CPP behavior, suggesting an increased sensitivity. These studies clearly show that pre-exposure during embryonic development affects subsequent cocaine sensitivity in longitudinal adults. PMID:27258254

  3. Polychlorinated biphenyl exposure and effects in tree swallows (Tachycineta bicolor) residing at eight locations

    Science.gov (United States)

    Yorks, A.L.; Rattner, B.A.; Melancon, M.J.

    1998-01-01

    Twelve-day-old Tree Swallow nestlings were studied at eight sites exhibiting a range of polychlorinated biphenyl (PCB) contamination. In addition to determining PCB concentrations in eggs, nestlings, and food items, hepatic cytochromes P450-associated monooxygenase activity quantified as a biomarker of exposure. Nestlings from several of the sites exhibited elevated PCB concentrations and P450 induction compared to a reference site, Furthermore, cytochromes P450 were correlated with PCB concentrations in nestling. Our findings indicate that likely routes of exposure include the direct materna! deposition of PCBs into the egg and the delivery of contaminated emerging aquatic insects to nestlings. We also examined reproductive and morphological parameters to determine if PCB exposure was adversely affecting swallows at these sites. Hatching success did not differ among sites. There were no dramatic effects on gross and histological gonadal morphology of nestlings, and there was complete concordance between phenotypic sex (gonadal morphology) and genotypic sex (as determined by PCR amplification of the sex chromosome). However, where nestling PCB exposure was substantial, clutch size and body weight differed from a reference site. Despite evidence of PCB exposure, only modest effects were observed in nestling swallows.

  4. Effects of low level lead exposure on associative learning and memory in the rat: Influences of sex and developmental timing of exposure.

    Science.gov (United States)

    Anderson, D W; Mettil, W; Schneider, J S

    2016-03-30

    Lead (Pb) exposure during development impairs a variety of cognitive, behavioral and neurochemical processes resulting in deficits in learning, memory, attention, impulsivity and executive function. Numerous studies have attempted to model this effect of Pb in rodents, with the majority of studies focusing on hippocampus-associated spatial learning and memory processes. Using a different paradigm, trace fear conditioning, a process requiring coordinated integration of both the medial prefrontal cortex and the hippocampus, we have assessed the effects of Pb exposure on associative learning and memory. The present study examined both female and male long evans rats exposed to three environmentally relevant levels of Pb (150 ppm, 375 ppm and 750 ppm) during different developmental periods: perinatal (PERI; gestation-postnatal day 21), early postnatal (EPN; postnatal days 1-21) and late postnatal (LPN; postnatal days 1-55). Testing began at postnatal day 55 and consisted of a single day of acquisition training, and three post training time points (1, 2 and 10 days) to assess memory consolidation and recall. All animals, regardless of sex, developmental window or level of Pb-exposure, successfully acquired conditioned-unconditioned stimulus association during training. However, there were significant effects of Pb-exposure on consolidation and memory recall at days 1-10 post training. In females, EPN and LPN exposure to 150 ppm Pb (but not PERI exposure) significantly impaired recall. In contrast, only PERI 150 ppm and 750 ppm-exposed males had significant recall deficits. These data suggest a complex interaction between sex, developmental window of exposure and Pb-exposure level on consolidation and recall of associative memories.

  5. Allergy arising from exposure to airborne contaminants in an insect rearing facility: Health effects and exposure control

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, D.

    1994-06-01

    In agricultural crop improvement, yield under various stress conditions and limiting factors is assessed experimentally. Of the stresses on plants which affect yield are those due to insects. Ostrinia nubilalis, the European corn borer (corn borer) is a major pest in sweet and field corn in the U.S. There are many ways to fight crop pests such as the corn borer, including (1) application of chemical insecticides, (2) application of natural predators and, (3) improving crop resistance through plant genetics programs. Randomized field trials are used to determine the effectiveness of pest management programs. These trials frequently consist of randomly selected crop plots to which well-defined input regimes are instituted. For example, corn borers might be released onto crop plots in several densities at various stages of crop development, then sprayed with different levels of pesticide. These experiments are duplicated across regions and, in some cases across the country, to determine, in this instance for example, the best pesticide application rate for a given pest density and crop development stage. In order to release these pests onto crop plots, one must have an adequate supply of the insect pest. In winter months studies are carried out in the laboratory to examine chemical and natural pesticide effectiveness, as well as such things as the role of pheromones in moth behavior. The advantage in field trials is that yield data can be garnered directly. In this country, insects are raised for crop research primarily through the US Department of Agriculture, in cooperation with public Land Grant Universities and, by the private sector agricultural concerns - seed companies and others. This study quantifies the airborne allergen exposure of persons working in a Land Grant University entomology lab were allergy to European corn borer was suspected.

  6. Reduction of implantation shadowing effect by dual-wavelength exposure photo process

    CERN Document Server

    Gu, Yiming; Lee Sang Yun; Roche, William; Sturtevant, John

    2003-01-01

    As transistor engineering continues to well below 100 nm length devices, ion implantation process tolerances are making these formerly "non-critical" lithography levels more and more difficult. In order to minimize the channeling effect and to obtain a controllable profile of dopant, an angle implantation is often required. However, a shadow area of resist pattern is always accompanied with an angle implantation. This shadowing effect consumes silicon real estate, and reduces the line edge placement (LEP) tolerances. Therefore, methodologies to reduce the shadowing effect in angled implantation become a critical consideration not only for device engineering but also for photolithography. Based on the model analysis, simulation and experiments, this paper presents an effective novel process utilizing dual-wavelength exposure (DWE) to reduce the shadowing effect. The DWE process is realized by two consecutive exposures for an I-line resist with a DUV stepper/scanner and an I-line stepper. The process leverages ...

  7. Evaluating chemical exposure and effect models for aquatic species with a focus on crude oil constituents

    NARCIS (Netherlands)

    Hoop, L. de

    2016-01-01

    The aim of this PhD thesis is to evaluate a suite of exposure and effect models on their applicability in ecological risk assessment for aquatic species and ecosystems. The focus is on oil constituents, as it is largely unknown whether current ecological models are applicable to crude oil and its co

  8. Bringing together Scientific Disciplines to better understand the health effects of Occupational Exposure to uranium

    International Nuclear Information System (INIS)

    Knowledge regarding the effects of chronic exposure to uranium comes up against the limitations specific to each discipline that takes an interest. The CURE (Concerted Uranium Research in Europe) project offers a scientific approach combining epidemiology, biology, toxicology and dosimetry to go beyond these limitations. (author)

  9. Discussion about modeling the effects of neutron flux exposure for nuclear reactor core analysis

    International Nuclear Information System (INIS)

    Methods used to calculate the effects of exposure to a neutron flux are described. The modeling of the nuclear-reactor core history presents an analysis challenge. The nuclide chain equations must be solved, and some of the methods in use for this are described. Techniques for treating reactor-core histories are discussed and evaluated

  10. Effects of Age of English Exposure, Current Input/Output, and Grade on Bilingual Language Performance

    Science.gov (United States)

    Bedore, Lisa M.; Pena, Elizabeth D.; Griffin, Zenzi M.; Hixon, J. Gregory

    2016-01-01

    This study evaluates the effects of Age of Exposure to English (AoEE) and Current Input/Output on language performance in a cross-sectional sample of Spanish-English bilingual children. First- (N = 586) and third-graders (N = 298) who spanned a wide range of bilingual language experience participated. Parents and teachers provided information…

  11. Effects of lung exposure to carbon nanotubes on female fertility and pregnancy. A study in mice

    DEFF Research Database (Denmark)

    Hougaard, Karin S.; Jackson, Petra; Kyjovska, Zdenka O.;

    2013-01-01

    We studied the effects of preconceptional exposure to multiwalled carbon nanotubes (MWCNTs): mature, female C57BL/6J mice were intratracheally instilled with 67μg NM-400 MWCNT, and the following day co-housed with mature males, in breeding pairs. Time to delivery of the first litter, litter param...

  12. A Meta-Analysis Summarizing the Effects of Pornography II: Aggression after Exposure.

    Science.gov (United States)

    Allen, Mike; And Others

    1995-01-01

    Examines by meta-analysis the effect that exposure to pornography produces on aggressive behavior under laboratory conditions considering a variety of possible moderating conditions. Demonstrates a homogeneous set of results showing that pictorial nudity reduces subsequent violent behavior, but that depictions of nonviolent sexual behavior and…

  13. The effects of the in utero glucocorticoid (GLC) exposure on fetal skeletal muscle growth in rats

    Science.gov (United States)

    Data from epidemiological studies suggest that adult muscle strength and lean body mass are related to birth weight and therefore, are influenced by the intra-uterine environment. The degree to which the effects on the musculature result from a nutrient deficit or its consequent exposure to above no...

  14. Effects of prenatal exposure to xylene on postnatal development and behavior in rats

    DEFF Research Database (Denmark)

    Hass, Ulla; Lund, S. P.; Simonsen, L.;

    1995-01-01

    The effects of prenatal exposure to the organic solvent xylene (dimethylbenzene, GAS-no 1330-20-7) on postnatal development and behavior in rats were studied. Pregnant rats (Mol:WIST) were exposed to 500 ppm technical xylene 6 h per day on gestation days 7-20. The dose level was selected so as no...

  15. Effects of prenatal exposure to toluene on postnatal development and behavior in rats

    DEFF Research Database (Denmark)

    Hougaard, K. S.; Hass, Ulla; Lund, S. P.;

    1999-01-01

    Development and neurobehavioral effects of prenatal exposure to toluene (CAS 108-88-3) were studied after exposing pregnant rats (Mol:WIST) to 1800 ppm of the solvent for 6 h daily on days 7-20 of gestation. Body weights of exposed offspring were lower until day 10 after parturition. Neurobehavio...

  16. Effects of Recent Exposure to a Conditioned Stimulus on Extinction of Pavlovian Fear Conditioning

    Science.gov (United States)

    Chan, Wan Yee Macy; Leung, Hiu T.; Westbrook, R. Frederick; McNally, Gavan P.

    2010-01-01

    In six experiments we studied the effects of a single re-exposure to a conditioned stimulus (CS; "retrieval trial") prior to extinction training (extinction-reconsolidation boundary) on the development of and recovery from fear extinction. A single retrieval trial prior to extinction training significantly augmented the renewal and reinstatement…

  17. EFFECTS OF DIBUTYL PHTHALATE IN MALE RABBITS FOLLOWING IN UTERO, ADOLESCENT OR POST-PUBERTAL EXPOSURE

    Science.gov (United States)

    Effects of dibutyl phthalate in male rabbits following in utero, adolescent, or post-pubertal exposureTy T. Higuchi1, Jennifer S. Palmer1, L. Earl Gray Jr2., and D. N. Rao Veeramachaneni11Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort

  18. Cumulative Effects of Exposure to Violence on Posttraumatic Stress in Palestinian and Israeli Youth

    Science.gov (United States)

    Dubow, Eric F.; Boxer, Paul; Huesmann, L. Rowell; Landau, Simha; Dvir, Shira; Shikaki, Khalil; Ginges, Jeremy

    2012-01-01

    We examine cumulative and prospective effects of exposure to conflict and violence across four contexts (ethnic-political, community, family, school) on posttraumatic stress (PTS) symptoms in Palestinian and Israeli youth. Interviews were conducted with 600 Palestinian and 901 Israeli (Jewish and Arab) children (ages 8, 11, and 14) and their…

  19. State-of-the-art exposure chamber for highly controlled and reproducible THz biological effects studies

    Science.gov (United States)

    Cerna, Cesario Z.; Elam, David P.; Echchgadda, Ibtissam; Sloan, Mark A.; Wilmink, Gerald J.

    2014-03-01

    Terahertz (THz) imaging and sensing technologies are increasingly being used at international airports for security screening purposes and at major medical centers for cancer and burn diagnosis. The emergence of new THz applications has directly resulted in an increased interest regarding the biological effects associated with this frequency range. Knowledge of THz biological effects is also desired for the safe use of THz systems, identification of health hazards, and development of empirically-based safety standards. In this study, we developed a state-of-the-art exposure chamber that allowed for highly controlled and reproducible studies of THz biological effects. This innovative system incorporated an industry grade cell incubator system that permitted a highly controlled exposure environment, where temperatures could be maintained at 37 °C +/- 0.1 °C, carbon dioxide (CO2) levels at 5% +/- 0.1%, and relative humidity (RH) levels at 95% +/- 1%. To maximize the THz power transmitted to the cell culture region inside the humid incubator, a secondary custom micro-chamber was fabricated and incorporated into the system. This micro-chamber shields the THz beam from the incubator environment and could be nitrogen-purged to eliminate water absorption effects. Additionally, a microscope that allowed for real-time visualization of the live cells before, during, and after THz exposure was integrated into the exposure system.

  20. Framework to determine the effectiveness of dietary exposure mitigation to chemical contaminants

    NARCIS (Netherlands)

    Fels, van der H.J.; Edwards, S.; Kennedy, M.; O'Hagan, A.; O'Mahony, C.; Scholz, G.; Steinberg, P.; Tennant, D.; Chiodini, A.

    2014-01-01

    In order to ensure the food safety, risk managers may implement measures to reduce human exposure to contaminants via food consumption. The evaluation of the effect of a measure is often an overlooked step in risk analysis process. The aim of this study was to develop a systematic approach for deter

  1. Morphologic and Immunologic effects in the rat after prenatal exposure to Cyclophosphamide

    NARCIS (Netherlands)

    Hessel EM; Verhoef A; van Loveren H; Piersma AH

    1993-01-01

    Several teratogens have been shown to alter postnatal immune function after prenatal exposure. Until now, relatively little is known about the perinatal maturation of the immune system and about the effects of teratogens on this process. Therefore, further research is necessary into the field of i

  2. ADVERSE EFFECTS OF PRENATAL EXPOSURE TO ATRAZINE DURING A CRITICAL PERIOD OF MAMMARY GLAND GROWTH

    Science.gov (United States)

    Prenatal exposure to 100 mg/kg atrazine (ATR) was previously shown to delay mammary gland (MG) development in the female offspring of Long Evans (LE) rats. To determine if the fetal MG was most sensitive to ATR effects during specific periods of development, timed-pregnant dams ...

  3. A NOVEL EFFECT OF DIOXIN: EXPOSURE DURING PREGNANCY SEVERELY IMPAIRS MAMMARY GLAND DIFFERENTIATION

    Science.gov (United States)

    A novel effect of dioxin: Exposure during pregnancy severely impairs mammary gland differentiation.Beth A. Vorderstrasse1, Suzanne E. Fenton2, Andrea A. Bohn3, Jennifer A. Cundiff1, and B. Paige Lawrence1,3,4 1Department of Pharmaceutical Sciences, Washington State Universi...

  4. Antepartum and Postpartum Exposure to Maternal Depression: Different Effects on Different Adolescent Outcomes

    Science.gov (United States)

    Hay, Dale F.; Pawlby, Susan; Waters, Cerith S.; Sharp, Deborah

    2008-01-01

    Background: Postpartum depression (PPD) is considered a major public health problem that conveys risk to mothers and offspring. Yet PPD typically occurs in the context of a lifelong episodic illness, and its putative effects might derive from the child's exposure to other episodes, in pregnancy or later childhood. The aim of the study is to test…

  5. Exposure-response functions for health effects of air pollutants based on epidemiological findings

    Energy Technology Data Exchange (ETDEWEB)

    Aunan, K.

    1995-10-01

    The objective of this report is to provide exposure-response functions for health effects and air pollution, which can be used in cost-effectiveness analyses of abatement measures. When cost-effective abatement strategies for air pollution are analyzed, and when air quality standards are set, it is important to have quantitative knowledge about health damage. In spite of their shortcomings, epidemiological studies provide a sound basis for exposure-response functions because they involve a random cross section of the population. In this report the exposure-response functions apply to the relation between air pollutant concentrations and relative effect frequencies, and involve the following health effect end-points: acute and chronic respiratory symptoms in children and adults, asthma episodes in children and adults, eye irritations, headache, lung damage in children, excess mortality, lung cancer incidence. The effects are attributed to one indicator component, which in many cases is particles, but for some effects NO{sub 2}, SO{sub 2}, O{sub 3}, or CO. A calculation procedure is suggested which makes it possible to estimate excess annual symptom-days for short-term effects using the annual average concentration. 103 refs., 1 table

  6. Effect of repeated benzene inhalation exposures on benzene metabolism, binding to hemoglobin, and induction of micronuclei.

    Science.gov (United States)

    Sabourin, P J; Sun, J D; MacGregor, J T; Wehr, C M; Birnbaum, L S; Lucier, G; Henderson, R F

    1990-05-01

    Metabolism of benzene is thought to be necessary to produce the toxic effects, including carcinogenicity, associated with benzene exposure. To extrapolate from the results of rodent studies to potential health risks in man, one must know how benzene metabolism is affected by species, dose, dose rate, and repeated versus single exposures. The purpose of our studies was to determine the effect of repeated inhalation exposures on the metabolism of [14C]benzene by rodents. Benzene metabolism was assessed by characterizing and quantitating urinary metabolites, and by quantitating 14C bound to hemoglobin and micronuclei induction. F344/N rats and B6C3F1 mice were exposed, nose-only, to 600 ppm benzene or to air (control) for 6 hr/day, 5 days/week for 3 weeks. On the last day, both benzene-pretreated and control animals were exposed to 600 ppm, 14C-labeled benzene for 6 hr. Individual benzene metabolites in urine collected for 24 hr after the exposure were analyzed. There was a significant decrease in the respiratory rate of mice (but not rats) pretreated with benzene which resulted in lower levels of urinary [14C]benzene metabolites. The analyses indicated that the only effects of benzene pretreatment on the metabolite profile in rat or mouse urine were a slight shift from glucuronidation to sulfation in mice and a shift from sulfation to glucuronidation in rats. Benzene pretreatment also had no effect, in either species, on formation of [14C]benzene-derived hemoglobin adducts. Mice and rats had similar levels of hemoglobin adduct binding, despite the higher metabolism of benzene by mice. This indicates that hemoglobin adduct formation occurs with higher efficiency in rats. After 1 week of exposure to 600 ppm benzene, the frequency of micronucleated, polychromatic erythrocytes (PCEs) in mice was significantly increased. Exposure to the same level of benzene for an additional 2 weeks did not further increase the frequency of micronuclei in PCEs. These results indicate

  7. Joint Effects of Exposure to Prenatal Infection and Peripubertal Psychological Trauma in Schizophrenia

    DEFF Research Database (Denmark)

    Debost, Jean-Christophe P G; Larsen, Janne Tidselbak; Munk-Olsen, Trine;

    2016-01-01

    : To estimate the independent and joint effects of exposure to prenatal infection and peripubertal psychological trauma on the risk of schizophrenia. DESIGN: Danish nationwide registers were linked in this prospective cohort study. We used survival analysis to report incidence rate ratios (IRRs...... of schizophrenia after exposure to both prenatal infection and peripubertal psychological trauma (IRR: 2.85, 95% CI: 2.32-3.51), with significant interaction between infection and peripubertal trauma on the multiplicative scale (P = .007). CONCLUSIONS: Our study demonstrated for the first time that prenatal...... infection and psychological trauma in peripubertal life can act in synergy to increase the risk of schizophrenia, with a potentially stronger susceptibility in males....

  8. Effects of maternal exposure to nano-alumina during pregnancy on neurodevelopment in offspring mice

    Institute of Scientific and Technical Information of China (English)

    丁勇

    2013-01-01

    Objective To observe the effects of maternal exposure to nano-alumina during pregnancy on the neurodevelopment in offspring mice.Methods Female ICR mice were exposed to nano-alumina 10 d before mating,and the nano-alumina exposure lasted till offspring mice were born.All the female mice were randomly divided into 5groups:solvent control group (saline) ,nano-carbon group (11.76 mg/ml) ,microalumina group (50 mg/ml) ,50 nm alumina group (50 mg/ml) ,and 13 nm alumina group (50 mg/ml) .All the mice were treated by

  9. Dietary acrylamide exposure among Finnish adults and children: The potential effect of reduction measures

    OpenAIRE

    Hirvonen, Tero; Jestoi, Marika; Tapanainen, Heli; Valsta, Liisa; Virtanen, Suvi M; Sinkko, Harri; Kronberg-Kippilä, Carina; Kontto, Jukka; Virtamo, Jarmo; Simell, Olli; Peltonen, Kimmo

    2011-01-01

    Abstract A deterministic exposure assessment using the Nusser method that adjusts for within-subject variation and for nuisance effects among Finnish children and adults was carried out. The food consumption data covered 2,038 adults (25?74 years old) and 1,514 children of one, three, and six years of age, with the data on foods? acrylamide content obtained from published Finnish studies. We found that acrylamide exposure was highest among the three-year-old children (median: 1.01 ...

  10. Acute exposure to silica nanoparticles aggravate airway inflammation: different effects according to surface characteristics

    OpenAIRE

    Park, Hye Jung; Sohn, Jung-Ho; Kim, Yoon-Ju; Park, Yoon Hee; Han, Heejae; Park, Kyung Hee; Lee, Kangtaek; Choi, Hoon; Um, Kiju; Choi,In-Hong; Park, Jung-Won; Lee, Jae-Hyun

    2015-01-01

    Silica nanoparticles (SNPs) are widely used in many scientific and industrial fields despite the lack of proper evaluation of their potential toxicity. This study examined the effects of acute exposure to SNPs, either alone or in conjunction with ovalbumin (OVA), by studying the respiratory systems in exposed mouse models. Three types of SNPs were used: spherical SNPs (S-SNPs), mesoporous SNPs (M-SNPs), and PEGylated SNPs (P-SNPs). In the acute SNP exposure model performed, 6-week-old BALB/c ...

  11. Effect of Exposure to Smoking in Movies on Young Adult Smoking in New Zealand

    Science.gov (United States)

    Gendall, Philip; Hoek, Janet; Edwards, Richard; Glantz, Stanton

    2016-01-01

    Onscreen Smoking Is a Form of Tobacco Marketing Tobacco advertising has been prohibited in New Zealand since 1990, and the government has set a goal of becoming a smokefree nation by 2025. However, tobacco marketing persists indirectly through smoking in motion pictures, and there is strong evidence that exposure to onscreen smoking causes young people to start smoking. We investigated the relationship between exposure to smoking in movies and youth smoking initiation among New Zealand young adults. Data from an online survey of 419 smokers and non-smokers aged 18 to 25 were used to estimate respondents’ exposure to smoking occurrences in 50 randomly-selected movies from the 423 US top box office movies released between 2008 and 2012. Analyses involved calculating movie smoking exposure (MSE) for each respondent, using logistic regression to analyse the relationship between MSE and current smoking behaviour, and estimating the attributable fraction due to smoking in movies. Effect of Smoking in Movies on New Zealand Youth Exposure to smoking occurrences in movies was associated with current smoking status. After allowing for the influence of family, friends and co-workers, age and rebelliousness, respondents’ likelihood of smoking increased by 11% for every 100-incident increase in exposure to smoking incidents, (aOR1.11; psmoking in movies was 54%; this risk could be substantially reduced by eliminating smoking from movies currently rated as appropriate for youth. We conclude that exposure to smoking in movies remains a potent risk factor associated with smoking among young adults, even in a progressive tobacco control setting such as New Zealand. Harmonising the age of legal tobacco purchase (18) with the age at which it is legal to view smoking in movies would support New Zealand’s smokefree 2025 goal. PMID:26960189

  12. Comparison of the Effects of Exposure to Different Particles or Energies on Behavioral Responding in Rats

    Science.gov (United States)

    Rabin, B. M.; Shukitt-Hale, B.; Joseph, J. A.; Carey, A.

    On exploratory class missions, astronauts will be exposed to a variety of heavy particles which differ in terms of quality and energy. Previous research has shown that exposure to 56Fe particles (1 GeV/n) can disrupt performance on taste aversion (CTA) learning and on operant responding using an ascending fixed-ratio schedule of reinforcement. How exposure to different types of particles and different energies will affect performance remains to be established. Rats were exposed to 56Fe (1 GeV/n, 5 GeV/n), 48Ti (1.2 GeV/n)) or 28Si (600 MeV/n) using the AGS or NSRL at Brookhaven National Laboratory. Three days following exposure, the rats were tested for the acquisition of an amphetamine-induced CTA. Compared to 1 GeV/n 56Fe, exposure to 5 GeV/n 56Fe particles required higher doses to disrupt the acquisition of an amphetamine-induced CTA. The dose-response curve for a 48Ti-induced disruption of CTA learning was similar to that produced by exposure to 1 GeV/n 56Fe particles, despite the difference in the LET of the two types of particles. In contrast the rats exposed to 28Si failed to show disruption of amphetamine-induced CTA learning, following exposure to 2.0-4.0 Gy. When tested on a ascending fixed-ratio operant task, the rats exposed to 5 GeV/n 56Fe, in contrast to the rats irradiated with 1 GeV/n 56Fe, did not show poorer performance than the non irradiated controls. These results show that the effects of exposure to heavy particles depend upon the specific particle, its energy, and the endpoint being tested. Supported by NASA Grants NAG9-1190 and NAG9-1529

  13. Multi-generational effects of polybrominated diphenylethers exposure: embryonic exposure of male American kestrels (Falco sparverius) to DE-71 alters reproductive success and behaviors.

    Science.gov (United States)

    Marteinson, Sarah C; Bird, David M; Shutt, J Laird; Letcher, Robert J; Ritchie, Ian J; Fernie, Kim J

    2010-08-01

    Polybrominated diphenylethers (PBDEs) are additive flame-retardants that are environmentally persistent and bioaccumulative compounds of particular concern to species at high trophic levels, including predatory birds. The developmental effects of in ovo exposure to male birds at environmentally relevant levels of the PBDE technical mixture, DE-71, on reproductive success and behaviors using captive American kestrels (Falco sparverius) were determined. Males were exposed in ovo by direct maternal transfer to DE-71 and unintentionally to low concentrations of hexabromocyclododecane (HBCD) at three mean +/- standard error DE-71 concentrations of 288.60 +/- 33.35 ng/g wet weight (low-exposure), 1130.59 +/- 95.34 ng/g wet weight (high-exposure), or background levels of 3.01 +/- 0.46 ng/g wet weight (control). One year following exposure, males were paired with unexposed females. Reproductive success was lower in the high exposure pairs: 43% failed to lay eggs while all other pairs laid complete clutches; they also laid smaller clutches and produced smaller eggs with reduced fertility, parameters that were negatively correlated with paternal in ovo concentrations of all PBDEs, as well as individual congeners and HBCD. Throughout courtship, there were fewer copulations by all in ovo exposed males, fewer mate-calls made by high-exposure males, and decreasing trends in pair-bonding and nest-box behaviors across treatments that continued during brood rearing. The reductions in clutch size and fertility were associated with the reduced frequencies of male courtship behaviors, and were associated with increasing concentrations of the PBDE congeners BDE-47, -99, -100, -53, -138, and HBCD. The results of the present study confirm effects noted in the F(0) generation and demonstrate that exposure to DE-71 affects multiple generations of this predatory avian species at environmentally relevant levels of exposure. PMID:20821627

  14. Direct and indirect effects of UV-B exposure on litter decomposition: a meta-analysis.

    Science.gov (United States)

    Song, Xinzhang; Peng, Changhui; Jiang, Hong; Zhu, Qiuan; Wang, Weifeng

    2013-01-01

    Ultraviolet-B (UV-B) exposure in the course of litter decomposition may have a direct effect on decomposition rates via changing states of photodegradation or decomposer constitution in litter while UV-B exposure during growth periods may alter chemical compositions and physical properties of plants. Consequently, these changes will indirectly affect subsequent litter decomposition processes in soil. Although studies are available on both the positive and negative effects (including no observable effects) of UV-B exposure on litter decomposition, a comprehensive analysis leading to an adequate understanding remains unresolved. Using data from 93 studies across six biomes, this introductory meta-analysis found that elevated UV-B directly increased litter decomposition rates by 7% and indirectly by 12% while attenuated UV-B directly decreased litter decomposition rates by 23% and indirectly increased litter decomposition rates by 7%. However, neither positive nor negative effects were statistically significant. Woody plant litter decomposition seemed more sensitive to UV-B than herbaceous plant litter except under conditions of indirect effects of elevated UV-B. Furthermore, levels of UV-B intensity significantly affected litter decomposition response to UV-B (PUV-B effects on litter decomposition were to a large degree compounded by climatic factors (e.g., MAP and MAT) (PUV-B on litter decomposition. No significant differences in UV-B effects on litter decomposition were found between study types (field experiment vs. laboratory incubation), litter forms (leaf vs. needle), and decay duration. Indirect effects of elevated UV-B on litter decomposition significantly increased with decay duration (PUV-B exposure intensity (30%) had significant direct effects on litter decomposition (PUV-B on litter decomposition.

  15. Effect of honey supplementation on toxicity of gasoline vapor exposure in rats

    Directory of Open Access Journals (Sweden)

    M B Abubakar

    2013-09-01

    Full Text Available Summary. Different health risks including haematotoxicity and weight loss have been reported for gasoline. Supplementation with antioxidants such as vitamins A, C, and E has been shown to ameliorate the toxicity effects of gasoline vapours exposure. Honey contains vitamins, and polyphenols that possess good antioxidant properties. The potential role of honey in preventing gasoline-induced haematotoxicity and weight loss was assessed in male rats. The rats were exposed to gasoline (11.13±1.1cm3/h 6 hours/day, 6 days/week, for 11 weeks. Honey (1.2g/kg body weight/day was administered for 11 weeks in one group and for 2 weeks in another group. The percentage weight gain and the mean corpuscular haemoglobin concentration (MCHC were significantly reduced in the gasoline exposed rats. On the other hand, the percentage of abnormal megakaryocytes in the bone marrow was higher in the gasoline exposed group. These findings suggest that gasoline vapours inhalation was associated with adverse alteration in weight, haematological indices, and bone marrow megakaryocytes of male rats. Administration of honey, did not improve the weight changes associated with gasoline exposure; it however improved the MCHC values and reduced the percentage of abnormal megakaryocytes.Industrial relevance. Honey is one of the famous natural products recognized for its enriched antioxidants composition which contribute significantly to its therapeutic effect in a number of diseases. The present study provides preliminary information for potential protective effect of tualang honey against the toxic effects of gasoline exposure in rat model. In view of the fact that exposure to constituents of gasoline is still rampant in most developing societies, the results of this study  may be used to further investigate the potential role of honey in ameliorating the toxicity effects of gasoline vapor exposure in rats.Keywords. Honey; gasoline; haematological indices; bone marrow

  16. The Lunar Environment: Determining the Health Effects of Exposure to Moon Dusts

    Science.gov (United States)

    Khan-Mayberry, Noreen

    2007-01-01

    The moon's surface is covered with a thin layer of fine, charged, reactive dust capable of layer of fine, charged, reactive dust capable of capable of entering habitats and vehicle compartments, where it can result in crewmember health problems. NASA formed the Lunar Airborne Dust Toxicity Advisory Group (LADTAG) to study the effects of exposure to Lunar Dust on human health. To date, no scientifically defensible toxicological studies have been performed on lunar dusts, specifically the determination of exposure limits and their affect on human health. The multi-center LADTAG (Lunar Airborne Dust Toxicology center LADTAG (Lunar Airborne Dust Toxicology Advisory Group) was formed in response to the Office of the Chief Health and Medical Office s (OCHMO) request to develop recommendations for defining risk (OCHMO) request to develop recommendations for defining risk defining risk criteria for human lunar dust exposure.

  17. Effect of UV exposure on photochromic glasses doped with transition metal oxides

    Science.gov (United States)

    El-Zaiat, S. Y.; Medhat, M.; Omar, Mona F.; Shirif, Marwa A.

    2016-07-01

    Silver halide photochromic glasses doped with one of the transition metal oxides, (Ti O2), (CoO),(Cr2 O3) are prepared using the melt quench technique. Glass samples are exposed to a UV source for 20 min. Spectral reflectance and transmittance at normal incidence of the prepared glasses are recorded before and after UV exposure with a double beam spectrophotometer in the spectral range 200-2500 nm. Dispersion parameters such as: single oscillator energy, dispersion energy and Abbe's number are deduced and compared. Absorption dispersion parameters, like optical energy gap for direct and indirect transitions, Urbach energy and steepness parameter, are deduced for the different glass prepared. Reflection loss, molar refractivity and electronic polarizability are deduced and compared. The effect of UV light exposure of these glasses on transmittance, reflectance, the linear and the predicted nonlinear optical parameters are investigated and discussed for the three transition metals. Nonlinear parameters increase in the three glass samples after UV exposure.

  18. Effect of environmental exposure to mercury on the functioning of the human body

    Directory of Open Access Journals (Sweden)

    Maciej Cyran

    2013-09-01

    Full Text Available Mercury is classified as a heavy metal and thus is commonly referred to as a death metal due to its high toxicity. In the environment it occurs in metallic form or in combination with other compounds. Amidst the sources of exposure to mercury, the most important environmental sources are dental amalgam and mercury vapor from the production of chlorine which is the most important source of occupational exposure. Mercury is easily soluble in fats, so it penetrates through biological membranes. Both - acute and chronic mercury poisoning causes characteristic clinical symptoms. There are several connections between exposure to this metal and toxic effects on the nervous system, cardiovascular system, endocrine system and kidneys. Thus mercury damages the structure of many organs and impairs their function

  19. Effect on Hyalella azteca after pulse exposure to environmentally realistic concentrations of permethrin

    DEFF Research Database (Denmark)

    Pedersen, Signe; Palmqvist, Annemette; Forbes, Valery E.

    Exposure of non-target aquatic organisms to pesticides is likely to occur in short pulses following periods of drain flow, surface run-off or spray drift. However, standard aquatic toxicity tests are primarily based on continuous and maintained exposure periods of 24 to 96 hours for acute effect...... realistic pulse exposure and concentration of a pyrethroid pesticide, permethrin, on the freshwater amphipod Hyalella azteca. Permethrin is a pyrethroid insecticide used in mosquito control and to control a wide range of insect pests on various crops and is known to be highly toxic to aquatic invertebrates....... H. azteca is widely distributed through North America where it is common as a food source for birds, fish and large invertebrates and is therefore considered as an ecologically important organism. In addition H. azteca has been extensively used as a test organism and is generally sensitive...

  20. The effects of children's exposure to domestic violence: a meta-analysis and critique.

    Science.gov (United States)

    Wolfe, David A; Crooks, Claire V; Lee, Vivien; McIntyre-Smith, Alexandra; Jaffe, Peter G

    2003-09-01

    A wide range of children's developmental outcomes are compromised by exposure to domestic violence, including social, emotional, behavioral, cognitive, and general health functioning. However, there are relatively few empirical studies with adequate control of confounding variables and a sound theoretical basis. We identified 41 studies that provided relevant and adequate data for inclusion in a meta-analysis. Forty of these studies indicated that children's exposure to domestic violence was related to emotional and behavioral problems, translating to a small overall effect (Zr = .28). Age, sex, and type of outcome were not significant moderators, most likely due to considerable heterogeneity within each of these groups. Co-occurrence of child abuse increased the level of emotional and behavioral problems above and beyond exposure alone, based on 4 available studies. Future research needs are identified, including the need for large-scale longitudinal data and theoretically guided approaches that take into account relevant contextual factors. PMID:14620578

  1. Dose Effects of Ion Beam Exposure on Deinococcus Radiodurans: Survival and Dose Response

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    To explore the survival and dose response of organism for different radiation sources is of great importance in the research of radiobiology. In this study, the survival-dose response of Deinococcus radiodurans (E.coli, as the control) for ultra-violet (UV), γ-rays radiation and ion beam exposure was investigated. The shoulder type of survival curves were found for both UV and γ-ray ionizing radiation, but the saddle type of survival curves were shown for H+ 、 N+( 20keV and 30keV) and Ar+ beam exposure. This dose effect of the survival initially decreased withthe increase in dose and then increased in the high dose range and finally decreased again in thehigher dose range. Our experimental results suggest that D. radiodurans, which is considerablyradio-resistant to UV and x-ray and γ-ray ionizing radiation, do not resist ion beam exposure.

  2. Dose Effects of Ion Beam Exposure on Deinococcus Radiodurans: Survival and Dose Response

    Science.gov (United States)

    Song, Dao-jun; Wu, Li-fang; Wu, Li-jun; Yu, Zeng-liang

    2001-02-01

    To explore the survival and dose response of organism for different radiation sources is of great importance in the research of radiobiology. In this study, the survival-dose response of Deinococcus radiodurans (E.coli, as the control) for ultra-violet (UV), γ-rays radiation and ion beam exposure was investigated. The shoulder type of survival curves were found for both UV and γ-ray ionizing radiation, but the saddle type of survival curves were shown for H+, N+(20keV and 30keV) and Ar+ beam exposure. This dose effect of the survival initially decreased with the increase in dose and then increased in the high dose range and finally decreased again in the higher dose range. Our experimental results suggest that D. radiodurans, which is considerably radio-resistant to UV and x-ray and γ-ray ionizing radiation, do not resist ion beam exposure.

  3. In vitro effect on Cryptosporidium parvum of short-term exposure to cathelicidin peptides.

    Science.gov (United States)

    Giacometti, Andrea; Cirioni, Oscar; Del Prete, Maria Simona; Skerlavaj, Barbara; Circo, Raffaella; Zanetti, Margherita; Scalise, Giorgio

    2003-04-01

    Two laboratory methods, a cell culture system and double fluorogenic staining, were used to study the viability and infective ability of Cryptosporidium parvum sporozoites and oocysts after short-term exposure to four cathelicidin peptides. The compounds, SMAP-29, BMAP-28, PG-1 and Bac7(1-35), exerted a strong cytotoxic effect on sporozoites, but did not affect the viability and function of oocysts consistently. Overall, in the sporozoite series, a percentage of the viable population decreased rapidly to less than detectable levels after 15 and 60 min exposure to the peptides at concentrations of 100 and 10 micro g/mL, respectively. In the oocyst series, no compound produced complete inhibition of parasite growth: 60-85% of the oocyst population was viable after 180 min exposure at 100 micro g/mL. SMAP-29 exerted the highest activity against both sporozoites and oocysts. PMID:12654759

  4. Effect of Exposure to Non-ionizing Radiation (Electromagnetic Fields on Human System: A Literature Review

    Directory of Open Access Journals (Sweden)

    Paula Rubya Souza C and acirc;mara

    2014-08-01

    Full Text Available The indiscriminate presence of radio base stations, which emit non-ionizing radiation (NIR, as well as the frequent use of mobile phones, can cause increased susceptibility of populations to the emergence of diseases such as cancers of the head and neck, biochemical, hematopoietic and hepatic changes, among others. Exposure to physical contamination, including NIR, has been implicated in numerous diseases, raising concerns about the widespread sources of exposure to this type of radiation. This paper reviews studies that have assessed associations between likely exposure to electromagnetic fields, such as radiofrequency transmissions, and many kinds of human diseases including cancer, as well as alerts to the current knowledge on the association between environmental exposure to NIR and the risk of development of adverse human health effects. This way, there appears to be an urgent need to reconsider exposure limits for low frequency and static magnetic fields, based on combined experimental and epidemiological research. [J Interdiscipl Histopathol 2014; 2(4.000: 187-190

  5. Effects of Exposure to the Sound from Seismic Airguns on Pallid Sturgeon and Paddlefish.

    Science.gov (United States)

    Popper, Arthur N; Gross, Jackson A; Carlson, Thomas J; Skalski, John; Young, John V; Hawkins, Anthony D; Zeddies, David

    2016-01-01

    This study examined the effects of exposure to a single acoustic pulse from a seismic airgun array on caged endangered pallid sturgeon (Scaphirhynchus albus) and on paddlefish (Polyodon spathula) in Lake Sakakawea (North Dakota, USA). The experiment was designed to detect the onset of physiological responses including minor to mortal injuries. Experimental fish were held in cages as close as 1 to 3 m from the guns where peak negative sound pressure levels (Peak- SPL) reached 231 dB re 1 μPa (205 dB re 1 μPa2·s sound exposure level [SEL]). Additional cages were placed at greater distances in an attempt to develop a dose-response relationship. Treatment and control fish were then monitored for seven days, euthanized, and necropsied to determine injuries. Necropsy results indicated that the probability of delayed mortality associated with pulse pressure following the seven day monitoring period was the same for exposed and control fish of both species. Exposure to a single pulse from a small air gun array (10,160 cm3) was not lethal for pallid sturgeon and paddlefish. However, the risks from exposure to multiple sounds and to sound exposure levels that exceed those reported here remain to be examined.

  6. Effect of sensory exposure on liking for fat- or sugar-reduced biscuits.

    Science.gov (United States)

    Biguzzi, Coralie; Lange, Christine; Schlich, Pascal

    2015-12-01

    This study investigates the effect of exposure to fat- or sugar-reduced biscuits on liking for these products. Two sets of biscuits were manufactured, each including a standard variant and 4 variants differing by the level of reduction of either fat or sugar content, to 33% of fat content or 28% of sugar content. Biscuit consumers were recruited to eat either the fat (n = 113) or the sugar-reduced set of biscuits (n = 106). They participated in 5 testing sessions, once a week, in laboratory conditions. During each session, they rated their liking of the 5 variants. At the end of each of the 4 first sessions, consumers were given 16 biscuits for their home consumption during the week. Participants were split into 3 groups of exposure: every week, a control group received the standard variant, a "direct" group received the most reduced variant and a "stepwise" group received a more and more reduced variant. After both control and stepwise exposure, almost no evolution of liking was observed. At the end of the direct exposure period to the 33% fat-reduced variant, liking for this variant significantly improved. On the contrary, after the direct exposure to the 28% sugar-reduced variant, liking only improved for 9 and 16% sugar-reduced variants.

  7. Effect of Electromagnetic Pulse Exposure on Permeability of Blood-testicle Barrier in Mice

    Institute of Scientific and Technical Information of China (English)

    XIAO-WU WANG; GUI-RONG DING; CHANG-HONG SHI; TAO ZHAO; JIE ZHANG; LI-HUA ZENG; GUO-ZHEN GUO

    2008-01-01

    Objective To study the effect of electromagnetic pulse (EMP) exposure on the permeability of blood-testicle barrier (BTB) in mice. Methods Adult male BALB/c mice were exposed to EMP at 200 kV/m for 200 pulses with 2 seconds interval. The mice were injected with 2% Evans Blue solution through caudal vein at different time points after exposure, and the permeability of BTB was monitored using a fluorescence microscope. The testis sample for the transmission electron microscopy was prepared at 2 h after EMP exposure. The permeability of BTB in mice was observed by using Evans Blue tracer and lanthanum nitrate tracer. Results After exposure, cloudy Evans Blue was found in the testicle convoluted seminiferous tubule of mice. Lanthanum nitrate was observed not only between testicle spermatogonia near seminiferous tubule wall and sertoli cells, but also between sertofi cells and primary spermatocyte or secondary spermatocyte. In contrast,lanthanum nitrate in control group was only found in the testicle sertoli cells between seminiferous tubule and near seminiferous tubule wall. Conclusion EMP exposure could increase the permeability of BTB in the mice.

  8. The effect of chronic exposure to tobacco smoke on the antibacterial defenses of the lung.

    Science.gov (United States)

    Huber, G L; Pochay, V E; Mahajan, V K; McCarthy, C R; Hinds, W C; Davies, P; Drath, D B; Sornberger, G C

    1977-01-01

    To evaluate the effects of cigarette smoking on the host defenses of the lung, male CD rats were exposed to fresh whole smoke for up to 60 consecutive days. Intrapulmonary deposition of smoke and animal exposure levels, quantified with decachlorobiphenyl and other smoke tracers, indicated a daily cigarette exposure equivalent to approximately a pack and a half per day in man. Pulmonary alveolar macrophage function in situ was quantified by the inactivation of an aerosolized challenge of Staphylococcus aureus six hours after inoculation. Controls (n=120) inactivated 88.8+/-0.64% of the staphylococci. Exposure to whole smoke did not impair intrapulmonary antistaphylococcal defenses, with inactivation rates of 89.8+/-0.97% (n=49) and 89.1+/-0.46% (n=74) at 30 and 60 days, respectively. Inactivation distribution frequency analysis in controls revealed that 7% of animals had inactivation values greater than two standard deviations from the mean. With prolonged exposure mean with less skewing towards the abnormal. Alveolar macrophages harvested from smoked animals were comparable in viability and in vitro antistaphylococcal activity to controls, appeared to be metabolically activated and had specific stereologic ultrastructural alterations. These studies indicate that chronic exposure to tobacco smoke does not impair, and in fact may stimulate, the host defenses of the lung, as evaluated by in vivo and in vitro pulmonary alveolar macrophage function. PMID:843645

  9. Air Distribution Effectiveness for Residential Mechanical Ventilation: Simulation and Comparison of Normalized Exposures

    Energy Technology Data Exchange (ETDEWEB)

    Petithuguenin, T.D.P.; Sherman, M.H.

    2009-05-01

    The purpose of ventilation is to dilute indoor contaminants that an occupant is exposed to. Even when providing the same nominal rate of outdoor air, different ventilation systems may distribute air in different ways, affecting occupants' exposure to household contaminants. Exposure ultimately depends on the home being considered, on source disposition and strength, on occupants' behavior, on the ventilation strategy, and on operation of forced air heating and cooling systems. In any multi-zone environment dilution rates and source strengths may be different in every zone and change in time, resulting in exposure being tied to occupancy patterns.This paper will report on simulations that compare ventilation systems by assessing their impact on exposure by examining common house geometries, contaminant generation profiles, and occupancy scenarios. These simulations take into account the unsteady, occupancy-tied aspect of ventilation such as bathroom and kitchen exhaust fans. As most US homes have central HVAC systems, the simulation results will be used to make appropriate recommendations and adjustments for distribution and mixing to residential ventilation standards such as ASHRAE Standard 62.2.This paper will report on work being done to model multizone airflow systems that are unsteady and elaborate the concept of distribution matrix. It will examine several metrics for evaluating the effect of air distribution on exposure to pollutants, based on previous work by Sherman et al. (2006).

  10. Immunotoxic effects of low level ozone exposure suggestive of an inducers in bronchial hyperresponiveness

    Institute of Scientific and Technical Information of China (English)

    SongH; LiDM

    2002-01-01

    For the city pollution of motor vehicle emissions,public air oxidizer exposure level has increasing tendence.As a representative of osidizer,ozone exposure is universal expecially at low levels in big city.Summarizing previous experimental study,which focuses on the exposure concentration at 0.125 ppm,the changes in inflammatory cytokines in animal airway suggest that low levels ozone expose activate cytokines resembling the bronchial hyperresponsiveness of atopy.Similarly the epidemiological study on adverse effects of ambient ozone exposure showed that the lower maxinal mid-expiratory flow of achoold children in exposed area where the concentration of ozone exceeded background levels only in the periphery of petroleum chemical enterprise were observed compared with those in control ares(P<0.05).This phenomenon of airway resistance increases as well as laboratory observation suggests that low level oxidizer exposure is one of the main risk factors of result in the increasing incidence of asthma in cities.

  11. Seasonal effect on biomarkers of exposure to petroleum hydrocarbons in fish from Kuwait's marine area.

    Science.gov (United States)

    Beg, M U; Al-Subiai, S N; Al-Jandal, N; Butt, S A; Beg, K R; Al-Husaini, M

    2015-11-30

    The aquatic biota of the Arabian Gulf deals with exposure to chronic oil pollution, several constituents of which cause induction of Cytochrome P450 1A that serves as a biomarker of AhR ligand exposure. In this study, fluorescent aromatic compounds (FACs) in bile and 7-ethoxyresorufin-o-deethylase (EROD) catalytic activity were determined as a measure of exposure biomarkers in two fish species, yellow fin seabream (Acanthopagrus latus) and tonguesole (Cynoglossus arel) captured from Kuwait Bay and outside the Bay area. FACs in fish bile determined by using fixed-wavelength fluorescence (FF) showed high fluorescence ratios between FF290/335 and FF380/430 indicating predominant exposure to low molecular weight, naphthalene-rich petroleum products (375±91.0 pg ml(-1)). Exposures to benzo(a)pyrene-type high-molecular weight polycyclic aromatic hydrocarbons (PAHs) originating from burnt fuel were also present in appreciable concentration in the bile. The ratio of petrogenic to pyrogenic hydrocarbon was twofold higher in winter compared to summer months in both species. Seasonal effect on EROD was significant in tonguesole in Auha site (P<0.05); whereas seabream resisted seasonal change. Tonguesole is considered to be a suitable bioindicator of oil pollution in Kuwait Bay area. PMID:26409815

  12. Estrogenic effect of propylparaben (propylhydroxybenzoate) in rainbow trout Oncorhynchus mykiss after exposure via food and water.

    Science.gov (United States)

    Bjerregaard, Poul; Andersen, Dorthe N; Pedersen, Knud L; Pedersen, Søren N; Korsgaard, Bodil

    2003-12-01

    The estrogenic effect of propylparaben was investigated in a rainbow trout Oncorhynchus mykiss test system. Propylparaben was administered orally to sexually immature rainbow trout every second day for up to 10 days in doses between 7 and 1830 mg kg(-1) 2 d(-1) and in the water at 50 and 225 microg l(-1) for 12 days. Plasma vitellogenin was measured before and during the exposures and the concentrations of propylparaben in liver and muscle were determined at the end of experiments. Increases in average plasma vitellogenin levels were seen at oral exposure to 33 mg propylparabenkg(-1) 2 d(-1); the most sensitive fish responded to 7 mg kg(-1). The ED(50) values for increase in vitellogenin synthesis were 35, 31 and 22 mg kg(-1) 2 d(-1) at day 3, 6 and 11, respectively. Exposure to 225 microg propylparabenl(-1) increased vitellogenin synthesis, but exposure to 50 microg l(-1) did not. Propylparaben showed little tendency to bioaccumulation in rainbow trout; less than 1 per thousand of the total amount of propylparaben administered orally at 1830 mg kg(-1) 2 d(-1) over the 10-d experimental period was retained in muscle and liver 24 h after the end of the experiment. Exposure to 225 microg propylparabenl(-1) for 12 d led to concentrations of 6700 and 870 microg propylparabenkg(-1) liver and muscle, respectively. Half lives for propylparaben were 8.6 h in liver and 1.5 h in muscle.

  13. Effects of Exposure to the Sound from Seismic Airguns on Pallid Sturgeon and Paddlefish.

    Science.gov (United States)

    Popper, Arthur N; Gross, Jackson A; Carlson, Thomas J; Skalski, John; Young, John V; Hawkins, Anthony D; Zeddies, David

    2016-01-01

    This study examined the effects of exposure to a single acoustic pulse from a seismic airgun array on caged endangered pallid sturgeon (Scaphirhynchus albus) and on paddlefish (Polyodon spathula) in Lake Sakakawea (North Dakota, USA). The experiment was designed to detect the onset of physiological responses including minor to mortal injuries. Experimental fish were held in cages as close as 1 to 3 m from the guns where peak negative sound pressure levels (Peak- SPL) reached 231 dB re 1 μPa (205 dB re 1 μPa2·s sound exposure level [SEL]). Additional cages were placed at greater distances in an attempt to develop a dose-response relationship. Treatment and control fish were then monitored for seven days, euthanized, and necropsied to determine injuries. Necropsy results indicated that the probability of delayed mortality associated with pulse pressure following the seven day monitoring period was the same for exposed and control fish of both species. Exposure to a single pulse from a small air gun array (10,160 cm3) was not lethal for pallid sturgeon and paddlefish. However, the risks from exposure to multiple sounds and to sound exposure levels that exceed those reported here remain to be examined. PMID:27505029

  14. The Alberta Oil Sands Community Exposure and Health Effects Assessment Program : methods report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-11-01

    The Alberta Oil Sands Community Exposure and Health Effects Assessment Program involved the development of a holistic approach to the study of personal exposure and the potential health impacts of airborne contaminants including volatile organic compounds (VOCs), sulphur dioxide (SO{sub 2}), nitrogen dioxide (NO{sub 2}), ozone (O{sub 3}) and particulates (both PM10 and PM2.5). Volunteer residents from Fort McMurray, Alberta were recruited to participate in neurocognitive tests and a health and nutrition survey. In addition, the local community identified several priority contaminants which were highlighted during a public hearing of the Alberta Energy and Utilities Board in relation to Syncrude's Mildred Lake Development Project. The approach to the study was based on the direct measurement of all routes of exposure to the contaminants (breathing, ingestion and skin contact), direct measurement of biomarkers, and daily logs of participant's activities. The choice of biomarkers was based on the ability of the laboratory to measure low levels of relevant biological markers, the most appropriate media for measuring the markers, and the burden placed on each volunteer. The final set of biological measures of exposure included trace metals (arsenic, cadmium, lead and uranium) nicotine, and metabolites of the BTEX compounds (benzene, toluene, ethylbenzene, and xylenes). The objective was to determine if chronic or occupational exposure to these contaminants cause structural alterations in the respiratory system that compromise oxygen absorption and lung elasticity. 82 refs., 14 tabs., 15 figs., 3 appendices.

  15. Differential effects of exposure to ambient vanilla and citrus aromas on mood, arousal and food choice

    Directory of Open Access Journals (Sweden)

    de Wijk René A

    2012-12-01

    Full Text Available Abstract Background Aromas have been associated with physiological, psychological affective and behavioral effects. We tested whether effects of low-level exposure to two ambient food-related aromas (citrus and vanilla could be measured with small numbers of subjects, low-cost physiological sensors and semi-real life settings. Tests included physiological (heart rate, physical activity and response times, psychological (emotions and mood and behavioral (food choice measures in a semi-real life environment for 22 participants. Results Exposure to ambient citrus aroma increased physical activity (P P P P P Conclusions The test battery used in this study demonstrated aroma-specific physiological, psychological and behavioral effects of aromas with similar appeal and intensities, and similar food-related origins. These effects could be measured in (semi- real life environments for freely moving subjects using relatively inexpensive commercially available physiological sensors.

  16. Assessing the Effectiveness of Ramp-Up During Sonar Operations Using Exposure Models.

    Science.gov (United States)

    von Benda-Beckmann, Alexander M; Wensveen, Paul J; Kvadsheim, Petter H; Lam, Frans-Peter A; Miller, Patrick J O; Tyack, Peter L; Ainslie, Michael A

    2016-01-01

    Ramp-up procedures are used to mitigate the impact of sound on marine mammals. Sound exposure models combined with observations of marine mammals responding to sound can be used to assess the effectiveness of ramp-up procedures. We found that ramp-up procedures before full-level sonar operations can reduce the risk of hearing threshold shifts with marine mammals, but their effectiveness depends strongly on the responsiveness of the animals. In this paper, we investigated the effect of sonar parameters (source level, pulse-repetition time, ship speed) on sound exposure by using a simple analytical model and highlight the mechanisms that limit the effectiveness of ramp-up procedures.

  17. The Effects of Exposure, Elevation and Tree Age on Seed Characteristics of Fagus orientalis Lipsky

    Directory of Open Access Journals (Sweden)

    Murat Ertekin

    2015-06-01

    Full Text Available Background and Purpose: Natural or artificial regeneration, rehabilitation, and conversion from coppice to high forest are important practices in Oriental beech (Fagus orientalis Lipsky forests in Turkey. Studies of the seeds of this species have increased in number because mast years are infrequent and seed germination is inhibited by dormancy. In this study we quantified the effects of tree age (40-59, 60-79 and 80-99 years, stand exposure (north, west, east and south and elevation (600 and 800 m a.s.l. on seed characteristics (germination, moisture content, and weight of Oriental beech. Material and Methods: The seeds used in this study were collected from natural beech forest at Kumluca, Bartin, in the western Black Sea region of Turkey. Experiments were carried out in the laboratory and the greenhouse of Bartin University. Results: Seed germination and moisture content varied significantly by elevation, and seed germination was strongly influenced by elevation. Moisture content was 14% at 600 m and 16% at 800 m. The effects of elevation and tree age on 100 seed weights were not significant but exposure had a significant effect. The highest 100 seed weight was recorded for trees on southern exposures and the highest germination percentage of 82% was recorded for trees on northern exposures. Conclusions: In conclusion, since oriental beech seedlings are produced by generative propagation method, seeds should be harvested in optimum distribution area of beech, from average ages and phenotypically plus tree.

  18. Effects of Elevated Ambient Temperature on Reproductive Outcomes and Offspring Growth Depend on Exposure Time

    Directory of Open Access Journals (Sweden)

    Huda Yahia Hamid

    2012-01-01

    Full Text Available Reproductive performance has been shown to be greatly affected by changes in environmental factors, such as temperature. However, it is also crucial to identify the particular stage of pregnancy that is most adversely affected by elevated ambient temperature. The aims of this study were to determine the effect on reproductive outcomes of exposure to elevated ambient temperature during different stages of pregnancy and to determine the effect of prenatal heat stress on offspring growth. Sixty pregnant rats were used in this study. The rats were divided equally into four groups as group 1 (control, group 2 (exposed to elevated temperature following implantation, group 3 (exposed to elevated temperature during pre- and periimplantation, and group 4 (exposed to elevated temperature during pre- and periimplantation and following implantation. Groups 3 and 4 had prolonged gestation periods, reduced litter sizes, and male-biased sex ratios. Moreover, the growth patterns of group 3 and 4 pups were adversely affected by prenatal exposure to elevated temperature. The differences between group 1 and group 3 and between group 1 and group 4 were highly significant. However, no significant differences were observed between groups 1 and 2 in the gestation length, sex ratios, and growth patterns. Thus, it can be concluded that exposure to elevated ambient temperature during pre- and periimplantation has stronger adverse effects on reproductive outcomes and offspring growth than postimplantation exposure.

  19. Methylmercury Exposure and Health Effects from Rice and Fish Consumption: A Review

    Directory of Open Access Journals (Sweden)

    Ping Li

    2010-06-01

    Full Text Available Methylmercury (MeHg is highly toxic, and its principal target tissue in humans is the nervous system, which has made MeHg intoxication a public health concern for many decades. The general population is primarily exposed to MeHg through consumption of contaminated fish and marine mammals, but recent studies have reported high levels of MeHg in rice and confirmed that in China the main human exposure to MeHg is related to frequent rice consumption in mercury (Hg polluted areas. This article reviews the progress in the research on MeHg accumulation in rice, human exposure and health effects, and nutrient and co-contaminant interactions. Compared with fish, rice is of poor nutritional quality and lacks specific micronutrients identified as having health benefits (e.g., n-3 long chain polyunsaturated fatty acid, selenium, essential amino acids. The effects of these nutrients on the toxicity of MeHg should be better addressed in future epidemiologic and clinical studies. More emphasis should be given to assessing the health effects of low level MeHg exposure in the long term, with appropriate recommendations, as needed, to reduce MeHg exposure in the rice-eating population.

  20. The effects of repeated exposure to graphic fear appeals on cigarette packages: A field experiment.

    Science.gov (United States)

    Dijkstra, Arie; Bos, Colin

    2015-03-01

    Experimental studies on the effects of graphic fear appeals on cigarette packages typically expose smokers in a single session to a fear appeal, although in practice the exposure is always repeated. The present study applied an improved study design with repeated exposure to fear appeals on cigarette packages. In this field-experiment, 118 smokers were assigned to 1 of 2 conditions with either graphic fear appeals or textual warnings on their cigarette packages. During 3 weeks, fear and disgust were assessed 6 times. The intention to quit smoking after 3 weeks and quitting activity during the 3 weeks were the dependent measures. The effects of 3 pretest individual difference moderators were tested: disengagement beliefs, number of cigarettes smoked a day, and readiness to quit. Three weeks of exposure to the graphic fear appeals led to a stronger intention to quit, but only when smokers scored low on disengagement beliefs, or were heavier smokers. In addition, smokers low in disengagement more often reported to have cut down on smoking in the graphic condition. There were no indications of habituation of fear and disgust over the 3 weeks. The effects of graphic fear appeals depended on smokers' characteristics: The moderators may explain the mixed findings in the literature. The lack of habituation may be caused by the renewal of the graphics every few days. The used field-experimental design with natural repeated exposure to graphics is promising. PMID:25621418

  1. Exposure to non-ionizing electromagnetic radiation and public health : review of safety levels; Exposicion a radiaciones no ionizantes ambientales y salud publica: Una revision de las bases biomedicas de los limites de seguridad

    Energy Technology Data Exchange (ETDEWEB)

    Ubeda, A.; Trillo, M. A.

    2005-07-01

    The potential health effects of the exposure to non-ionizing electromagnetic radiation are a source of increasing interest on the part of the public and the authorities. This article summarizes the theoretical-experimental basis supporting the safety levels proposed by international committees, and reviews the recent scientific literature on non-ionizing radiation's bioeffects that are relevant to the validation or modification of the present exposure limits. Because of its social interest, special consideration is given to power frequency fields (50-60Hz) and to the radio communication signals of mobile telephony. The paper also describes how interpretations of the scientific evidence, other than those of the international committees, have generated some controversy and have provided a basis for more restrictive limits, like those adopted in Europe by Switzerland and Italy. The article also identifies some gaps in the present scientific knowledge on the bioelectromagnetics discipline and proposes that additional research is needed to complete our present knowledge on the biological responses to non-ionizing radiation. (Author) 80 refs.

  2. Effect of Prenatal Exposure to Lead on Estrogen Action in the Prepubertal Rat Uterus

    OpenAIRE

    Tchernitchin, Andrei N.; Leonardo Gaete; Rodrigo Bustamante; Aracelly Báez

    2012-01-01

    Lead is a widely spread environmental pollutant known to affect both male and female reproductive systems in humans and experimental animals and causes infertility and other adverse effects. The present paper investigated the effects of prenatal exposure to lead on different parameters of estrogen stimulation in the uterus of the prepubertal rat. In prenatally and perinatally exposed rats, estrogen-induced endometrial eosinophilia, endometrial stroma edema, and eosinophil migration towards th...

  3. Effects of pyrene exposure and temperature on early development of two co-existing Arctic copepods

    DEFF Research Database (Denmark)

    Grenvald, Julie Cornelius; Nielsen, Torkel Gissel; Hjorth, Morten

    2013-01-01

    Oil exploration is expected to increase in the near future in Western Greenland. At present, effects of exposure to oil compounds on early life-stages of the ecologically important Calanus spp. are unknown. We investigated the effects of the oil compound pyrene, on egg hatching and naupliar...... to pyrene from an oil spill may reduce the standing stock of Calanus, which can lead to less energy available to higher trophic levels in the Arctic marine food web...

  4. Individual differences in the effects of prenatal stress exposure in rodents

    OpenAIRE

    Boersma, Gretha J.; Tamashiro, Kellie L.

    2014-01-01

    Exposure to prenatal stress alters the phenotype of the offspring in adulthood. When the prenatal and adult environments do not match, these alterations may induce pathology risk. There are, however, large individual differences in the effects of prenatal stress. While some individuals seem vulnerable, others appear to be relatively resistant to its effects. In this review we discuss potential mechanisms underlying these individual differences with a focus on animal models. Differences betwee...

  5. Effect of regular aerobic exercise with ozone exposure on peripheral leukocyte populations in Wistar male rats

    OpenAIRE

    Afshar Jafari; Mohammad Ali Hosseinpour faizi; Fariba Askarian; Hassan Pourrazi

    2009-01-01

    • BACKGROUND: The immune system in endurance athletes may be at risk for deleterious effects of gasous pollutants such as ambient ozone. Therefore, this study was performed to assess the effect of regular aerobic exercise with ozone exposure on peripheral leukocytes populations in male Wistar rats.
    • METHODS: Twenty eight 8 weeks old rats were selected and randomly divided into four groups of ozone-u...

    • Risk of Adverse Health and Performance Effects of Celestial Dust Exposure

      Science.gov (United States)

      Scully, Robert R.; Meyers, Valerie E.

      2015-01-01

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

    • Effects of Neonatal Methamphetamine and Thioperamide Exposure on Spatial Memory Retention and Circadian Activity Later in Life

      OpenAIRE

      Eastwood, Emily; Charles N. Allen; Raber, Jacob

      2012-01-01

      Methamphetamine (MA) use increases the likelihood of engaging in risky sexual behavior and most MA-using women are of child-bearing age. Therefore, cognitive effects following MA exposure to the developing brain are concerning. Exposure of mice to MA during hippocampal development causes cognitive impairments in adulthood. These effects are more severe in female than male mice and mimicked by the H3 receptor antagonist thioperamide (THIO). In this study, we assessed whether neonatal exposure ...

    • Effect of regular aerobic exercise with ozone exposure on peripheral leukocyte populations in Wistar male rats

      Directory of Open Access Journals (Sweden)

      Afshar Jafari

      2009-09-01

      Full Text Available

      • BACKGROUND: The immune system in endurance athletes may be at risk for deleterious effects of gasous pollutants such as ambient ozone. Therefore, this study was performed to assess the effect of regular aerobic exercise with ozone exposure on peripheral leukocytes populations in male Wistar rats.
      • METHODS: Twenty eight 8 weeks old rats were selected and randomly divided into four groups of ozone-unexposed anduntrained (control or group 1, n = 6, ozone-exposed and untrained (group 2, n = 6, ozone-unexposed and trained (group 3, n = 8, ozone-exposed and trained (group 4, n = 8. All animals in groups 3 and 4 were regularly running (20 m/min, 30 min/day on a treadmill for 7 weeks (5 day/week. After the last ozone exposure [0.3 ppm, 30 min per sessions], blood samples were obtained from the cardiac puncture and hematological parameters as well as blood lactate were measured using automatic analyzers. Data were expressed as means (± SD and analyzed by ANOVA and Pearson's correlation tests at p < 0.05.
      • RESULTS: All the hematological parameters differences (except RBC and hemoglobin rate were significantly higher in the trained groups (p < 0.001. However, ozone-induced leukocytosis in the trained (but not in the sedentary rats was statistically higher than in the counterpart groups.
      • CONCLUSIONS: Repeated acute ozone exposure has more additive effect on peripheral leukocyte counts in active animals. But, more researches are needed to identify effects of ozone exposure on other components of the immune system in athletes and non-athletes.
      • KEYWORDS: Moderate Aerobic Exercise, Ozone Exposure,  eukocytosis, Wistar Rats.

    • Carry-over effects of smoking cue exposure on working memory performance

      Science.gov (United States)

      Wilson, Stephen J.; Sayette, Michael A.; Fiez, Julie A.; Brough, Elizabeth

      2009-01-01

      The present study investigated the effects of drug cue exposure on working memory performance in cigarette smokers. Adult smokers (N=23) deprived for 12 hr performed a working memory task during which they were exposed to three types of task-irrelevant stimuli: Pictures containing smoking related-content, pictures devoid of smoking content, and a fixation cross. Consistent with prior research, we found that drug cue exposure affected the processing of subsequent items (i.e., carry-over effects). Specifically, we found that working memory performance was worse on trials containing neutral pictures preceded by trials containing smoking cues compared with performance on trials containing neutral pictures preceded by trials not containing smoking-related stimuli. Previously observed effects of smoking cue exposure on cognitive processing were replicated but only after removing trials subject to carry-over effects. These results replicate and extend previous research demonstrating similar effects and highlight the significant methodological and conceptual implications of carry-over effects. PMID:17454718

    • The delayed effects of radiation exposure among atomic bomb survivors, Hiroshima and Nagasaki, 1945-79

      International Nuclear Information System (INIS)

      The most important radiation-induced late medical effect in the atomic bomb survivors of Hiroshima and Nagasaki has been the increased occurrence of certain neoplasms, specifically, leukemia and cancers of the thyroid, lung, and breast. Other definite radiation-related effects include an increase in posterior lenticular opacities, chromosome aberrations in peripheral blood lymphocytes, and some abnormalities of growth and development following irradiation while in utero or during childhood. Moderate to fairly strong associations between A-bomb exposure and the increased occurrence of stomach cancer, multiple myeloma, and several other types of cancer have been observed. Radiation relationships also are suggestive for alterations of certain aspects of immune mechanisms and the increased occurrence of myelofibrosis. No increase in genetic effects has been demonstrated in the children born of exposed parents, and studies to data have been negative for evidence of increased infertility, accelerated aging, or increased mortality from diseases other than cancer. In general, the radiation dose-response relationships for most positive effects have been higher in Hiroshima than in Nagasaki, and the shape of the dose-response curves for certain effects is different in the two cities. These differences may be related to differences in the quality of the radiation from the two A-bombs. For several radiation-related effects the latent period following exposure is shorter and the incidence rate is higher in personse exposed when young as compared to exposure later in life. (author)

    • Biological and sanitary effects of non ionizing radiations

      International Nuclear Information System (INIS)

      The objective of this day was to encourage the collaborations, especially multidisciplinary, on the biological, clinical, epidemiological and dosimetry aspects. The different presentations are as follow: the magneto reception among animals; the health and radio frequencies foundation; expo-metry to radio frequency fields: dosemeters evaluation; the electro-optical probes as tool of hyper frequency dosimetry; characterisation of emissions produced by the low consumption fluo-compact lamps in the perspective of persons exposure; strong and weak points of epidemiology; numerical dosimetry in low frequency magnetic and/or electric field; exposure of the French population to the 50 Hz magnetic field: first results for the Ile-de-france and Rhone alpes areas; characterisation of the exposure to the very low frequency magnetic fields in the town of Champlan; measurement of the residential exposure of children to the extremely low frequency, very low frequency and radiofrequency (E.L.F., V.L.F. and R.F.) fields and modeling of the high voltage magnetic field face to the child leukemia; effects of radiofrequency signals of wireless communications on the young animals; study of combined effects of 2.45 GHz microwaves and a known mutagen on DNA by two different approaches; effects on the oxidizing stress of nervous cells exposure to an (enhanced data rates for GSM evolution) E.D.G.E. signal; is environmental epidemiology still a science; cardiac implants and exposure to 50 Hz electromagnetic fields in occupational environment; the tanning by artificial UV radiation: norms and legislation; mobiles phones, Wi Fi and other wireless communications; effects on health of 50-60 Hz electromagnetic fields; natural and artificial ultraviolet radiations: a proved risk. (N.C.)

    • Efficacy of chlorfenapyr against adult Tribofium castaneum exposed on concrete: effects of exposure interval, concentration and the presence of a food source after exposure

      Institute of Scientific and Technical Information of China (English)

      Frank H. Arthur

      2009-01-01

      Chlorfenapyr, an insecticidal pyrrole, was applied to concrete arenas at concentrations of 1.1, 0.825, 0.55, and 0.275 g of active ingredient [AI]/m2. Adult Tribolium castaneum (Herbst), the red flour beetle, were exposed for 2, 4, or 8 h at each concentration, then removed and held either with or without food (wheat flour) for 7 days. Survival was assessed when the beetles were removed from the exposure arenas and daily during the post-exposure period. In the presence of food, survival was high regardless of concentration and the day on which post-treatment survival was assessed, but survival did decrease as the exposure period increased from 4 to 8 h. When the beetles were not given food after exposure, survival at each concentration and exposure period declined during the 1-week post-exposure assessments. This pattern of decrease could be described by linear and non-linear equations. Results show the presence of food material greatly compromised effectiveness of the insecticide, and emphasize the importance of cleaning and sanitation in conjunction with insecticide treatments.

    • Neurobehavioral effects of exposure to propionic acid revisited-Does psychosocial stress interfere with distractive effects in volunteers?

      Science.gov (United States)

      Pacharra, Marlene; Schäper, Michael; Kleinbeck, Stefan; Blaszkewicz, Meinolf; Golka, Klaus; van Thriel, Christoph

      2016-07-01

      Local irritants stimulate the nervous system via chemosensory pathways that trigger cognitive distraction, subjective complaints about impaired health, and physiological defense reflexes (e.g. eye-blinks). At workplaces and in the environment chemical exposures often co-occur with psychosocial stress. This study investigated if stress modulates adverse effects of exposure to the local irritant and malodorant propionic acid (PA). Forty-eight participants were randomly assigned to an experimental (false negative feedback+salient surveillance) or control group. In a cross-over design, both groups were exposed for 4h to PA in concentrations of 0.3 and 0-20ppm (time-weighted average=10ppm). In the experimental group, the stress protocol induced moderate psychosocial stress as indicated by salivary cortisol and subjective responses. Despite concentration-dependent increases in chemosensory perceptions and symptoms, the level of exposure to PA had no impact upon the results of four out of six neurobehavioral tests. In the sustained attention test, there was a significant increase in error rates that corresponded to the exposure levels. However, a concentration-dependent impairment of spatial working memory and an adverse increase in eye-blink frequency were restricted to the control group. Stressed participants had shorter simple reaction times and high eye-blink frequency irrespective of exposure suggesting enhanced alertness. Psychosocial stress increased complaints, ocular irritation and unspecific symptoms at the end of the 0.3ppm exposure to a level that was comparable with that in the control group during exposure to 0-20ppm. Results indicate that the adverse effects of a local irritant and psychosocial stress are non-additive.

    • Exposure and post-exposure effects of endosulfan on Bufo bufo tadpoles: morpho-histological and ultrastructural study on epidermis and iNOS localization.

      Science.gov (United States)

      Bernabò, Ilaria; Guardia, Antonello; La Russa, Daniele; Madeo, Giuseppe; Tripepi, Sandro; Brunelli, Elvira

      2013-10-15

      Endosulfan is a persistent organic pollutant (POP) that has lethal and sublethal effects on non-target organisms, including amphibians. In a laboratory study, we investigated direct and post-exposure effects of endosulfan on Bufo bufo tadpoles. For this purpose we exposed the tadpoles to a single short-term contamination event (96 h) at an environmentally-realistic concentration (200 μg endosulfan/L). This was followed by a recovery period of 10 days when the experimental animals were kept in pesticide-free water. The endpoints were assessed in terms of mortality, incidence of deformity, effects on behavior, and the morpho-functional features of the epidermis. We found that a short-term exposure to the tested concentration of endosulfan did not cause mortality but induced severe sublethal effects, such as hyperactivity, convulsions, and axis malformations. Following relocation to a pesticide-free environment, we noted two types of response within the experimental sample, in terms of morphological and behavioral traits. Moreover, by using both ultrastructural and a morpho-functional approach, we found that a short-term exposure to endosulfan negatively affected the amphibian epidermis. We also observed several histo-pathological alterations: increased mucous secretion, an increase in intercellular spaces and extensive cell degeneration, together with the induction of an inducible isoform of nitric oxide synthase (iNOS). Following the post-exposure period, we found large areas of epidermis in which degeneration phenomena were moderate or absent, as well as a further increase in iNOS immunoreactivity. Thus, after 10 days in a free-pesticide environment, the larval epidermis was able to partially replace elements that had been compromised due to a physiological and/or a pathological response to the pesticide. These results highlight the need for both exposure and post-exposure experiments, when attempting to assess pollutant effects.

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

      DEFF Research Database (Denmark)

      Isling, Louise Krag; Boberg, Julie; Jacobsen, Pernille Rosenskjold;

      2014-01-01

      This study examined late-life effects of perinatal exposure of rats to a mixture of endocrine-disrupting contaminants. Four groups of 14 time-mated Wistar rats were exposed by gavage from gestation day 7 to pup day 22 to a mixture of 13 anti-androgenic and estrogenic chemicals including phthalates...... group. Developmental exposure of rats to the highest dose of a human-relevant mixture of endocrine disrupters induced adverse effects late in life, manifested as earlier female reproductive senescence, reduced sperm counts, higher score for prostate atypical hyperplasia, and higher incidence...... of pituitary tumors. These delayed effects highlight the need for further studies on the role of endocrine disrupters in hormone-related disorders in aging humans....

    • Co-Exposure with Fullerene May Strengthen Health Effects of Organic Industrial Chemicals

      DEFF Research Database (Denmark)

      Lehto, M.; Karilainen, T.; Rog, T.;

      2014-01-01

      In vitro toxicological studies together with atomistic molecular dynamics simulations show that occupational co-exposure with C-60 fullerene may strengthen the health effects of organic industrial chemicals. The chemicals studied are acetophenone, benzaldehyde, benzyl alcohol, m-cresol, and toluene...... co-exposure scenarios in in vitro studies where acute cytotoxicity and immunotoxicity of C-60 and organic chemicals are tested together and alone by using human THP-1-derived macrophages. Statistically significant co-effects are observed for an unfiltered mixture of benzaldehyde and C-60 that is more...... cytotoxic than benzaldehyde alone, and for a filtered mixture of m-cresol and C-60 that is slightly less cytotoxic than m-cresol. Hydrophobicity of chemicals correlates with co-effects when secretion of pro-inflammatory cytokines IL-1 beta and TNF-alpha is considered. Complementary atomistic molecular...

    • Effects of diethylstilbestrol exposure during gestation on both maternal and offspring behavior.

      Directory of Open Access Journals (Sweden)

      Kazuya eTomihara

      2015-03-01

      Full Text Available Endocrine disruption during gestation impairs the physical and behavioral development of offspring. However, it is unclear whether endocrine disruption also impairs maternal behavior and in turn further contributes to the developmental and behavioral dysfunction of offspring. We orally administered the synthetic non-steroidal estrogen diethylstilbestrol (DES to pregnant female C57BL/6J mice from gestation day 11–17 and then investigated the maternal behavior of mothers. In addition, we examined the direct effects of in utero DES exposure and the indirect effects of aberrant maternal behavior on offspring using the cross-fostering method. In mothers, endocrine disruption during gestation decreased maternal behavior. In addition, endocrine disruption of foster mother influenced anxiety-related behavior and passive avoidance learning of pups regardless of their exposure in utero. The influence of DES exposure in utero, irrespective of exposure to the foster mother, was also shown in female offspring. These results demonstrate the risks of endocrine disruptors on both mother as well as offspring and suggest that developmental deficits may stem from both in utero toxicity and aberrant maternal care.

    • Delayed emergence of behavioral and electrophysiological effects following juvenile ketamine exposure in mice.

      Science.gov (United States)

      Nagy, L R; Featherstone, R E; Hahn, C G; Siegel, S J

      2015-09-15

      Frequent ketamine abuse in adulthood correlates with increased risk of psychosis, as well as cognitive deficits, including disruption of higher-order executive function and memory formation. Although the primary abusers of ketamine are adolescents and young adults, few studies have evaluated its effects on juvenile cognition. Therefore, the current study analyzes the effect of adolescent ketamine exposure on cognitive development. Juvenile mice (4 weeks of age) were exposed to chronic ketamine (20 mg kg(-1), i.p. daily) for 14 days. Mice were tested immediately after exposure in the juvenile period (7 weeks of age) and again as adults (12 weeks of age). Measures included electroencephalography (EEG) in response to auditory stimulation, the social choice test, and a 6-arm radial water maze task. Outcome measures include low-frequency EEG responses, event-related potential (ERP) amplitudes, indices of social behavior and indices of spatial working memory. Juvenile exposure to ketamine was associated with electrophysiological abnormalities in adulthood, particularly in induced theta power and the P80 ERP. The social choice test revealed that ketamine-exposed mice failed to exhibit the same age-related decrease in social interaction time as controls. Ketamine-exposed mice outperformed control mice as juveniles on the radial water maze task, but did not show the same age-related improvement as adult controls. These data support the hypothesis that juvenile exposure to ketamine produces long-lasting changes in brain function that are characterized by a failure to progress along normal developmental trajectories.

    • The Effects of Technology Innovativeness and System Exposure on Student Acceptance of E-textbooks

      Directory of Open Access Journals (Sweden)

      Madison N. Ngafeeson

      2015-01-01

      Full Text Available The efforts of educators in the last three decades have, among other things, focused on the use of information technology (IT in education. It has become commonplace to view information systems both as an effective carrier of course content as well as a cost-effective tool to improve student learning outcomes. One of such technologies is the e-book. Decision-makers in the education field need make sense of this technological transformation. However, despite the growing popularity of e-books in higher education, its adoption by students is yet to be crystalized. This study exploits the technology acceptance model (TAM framework to examine student acceptance of e-textbooks as “internally” impacted by technology innovativeness and “externally” influenced by system exposure. The results showed that students’ technology innovativeness is associated with student acceptance of e-textbooks and that system exposure was a strong moderator of the TAM relationships. The findings suggest that students’ openness to new technology, in general, is likely to positively affect the adoption of a specific new instructional technology. Additionally, system exposure was found to be a significant moderator of the TAM relationships. It is concluded that students’ technology innovativeness and system exposure must therefore be factored into instructional technology usage decision-making models.

    • Prevention effects on trajectories of African American adolescents' exposure to interparental conflict and depressive symptoms.

      Science.gov (United States)

      Barton, Allen W; Beach, Steven R H; Kogan, Steven M; Stanley, Scott M; Fincham, Frank D; Hurt, Tera R; Brody, Gene H

      2015-04-01

      The present study investigates the trajectory of children's exposure to interparental conflict during adolescence, its effects on adolescents' psychological adjustment, as well as the ability of a family-centered prevention program to alter this trajectory. A total of 331 African American couples with an adolescent or preadolescent child participated in a randomized control trial of the Promoting Strong African American Families program, a newly developed program targeting couple and cocaregiving processes. Using a multi-informant, latent growth curve approach, child exposure to interparental conflict during adolescence was found to be stable over a period of 2 years among families in the control group, but significantly declined among families in the treatment condition. Rates of change were significantly different between intervention and control groups based on parents' report of youth exposure to interparental conflict, but not for child's report. Structural equation models found trajectory parameters of interparental conflict predicted changes in adolescent depressive symptoms, with increasing rates of changes in conflict associated with increases in adolescent internalizing symptoms over the 2-year duration of the study. Finally, a significant indirect effect was identified linking treatment, changes in parents' reports of child exposure to interparental conflict, and adolescent depressive symptoms. The implications for research and intervention are discussed.

  1. The effect of blue light exposure in an ocular melanoma animal model

    Directory of Open Access Journals (Sweden)

    Odashiro Alexandre N

    2009-04-01

    Full Text Available Abstract Background Uveal melanoma (UM cell lines, when exposed to blue light in vitro, show a significant increase in proliferation. In order to determine if similar effects could be seen in vivo, we investigated the effect of blue light exposure in a xenograft animal model of UM. Methods Twenty New Zealand albino rabbits were injected with 1.0 × 106 human UM cells (92.1 in the suprachoroidal space of the right eye. Animals were equally divided into two groups; the experimental group was exposed to blue light, while the control group was protected from blue light exposure. The eyes were enucleated after sacrifice and the proliferation rates of the re-cultured tumor cells were assessed using a Sulforhodamine-B assay. Cells were re-cultured for 1 passage only in order to maintain any in vivo cellular changes. Furthermore, Proliferating Cell Nuclear Antigen (PCNA protein expression was used to ascertain differences in cellular proliferation between both groups in formalin-fixed, paraffin-embedded eyes (FFPE. Results Blue light exposure led to a statistically significant increase in proliferation for cell lines derived from intraocular tumors (p Conclusion There is an increasing amount of data suggesting that blue light exposure may influence the progression of UM. Our results support this notion and warrant further studies to evaluate the ability of blue light filtering lenses to slow disease progression in UM patients.

  2. Delayed emergence of behavioral and electrophysiological effects following juvenile ketamine exposure in mice.

    Science.gov (United States)

    Nagy, L R; Featherstone, R E; Hahn, C G; Siegel, S J

    2015-01-01

    Frequent ketamine abuse in adulthood correlates with increased risk of psychosis, as well as cognitive deficits, including disruption of higher-order executive function and memory formation. Although the primary abusers of ketamine are adolescents and young adults, few studies have evaluated its effects on juvenile cognition. Therefore, the current study analyzes the effect of adolescent ketamine exposure on cognitive development. Juvenile mice (4 weeks of age) were exposed to chronic ketamine (20 mg kg(-1), i.p. daily) for 14 days. Mice were tested immediately after exposure in the juvenile period (7 weeks of age) and again as adults (12 weeks of age). Measures included electroencephalography (EEG) in response to auditory stimulation, the social choice test, and a 6-arm radial water maze task. Outcome measures include low-frequency EEG responses, event-related potential (ERP) amplitudes, indices of social behavior and indices of spatial working memory. Juvenile exposure to ketamine was associated with electrophysiological abnormalities in adulthood, particularly in induced theta power and the P80 ERP. The social choice test revealed that ketamine-exposed mice failed to exhibit the same age-related decrease in social interaction time as controls. Ketamine-exposed mice outperformed control mice as juveniles on the radial water maze task, but did not show the same age-related improvement as adult controls. These data support the hypothesis that juvenile exposure to ketamine produces long-lasting changes in brain function that are characterized by a failure to progress along normal developmental trajectories. PMID:26371763

  3. Effects of chronic ethanol exposure on neuronal function in the prefrontal cortex and extended amygdala.

    Science.gov (United States)

    Pleil, Kristen E; Lowery-Gionta, Emily G; Crowley, Nicole A; Li, Chia; Marcinkiewcz, Catherine A; Rose, Jamie H; McCall, Nora M; Maldonado-Devincci, Antoniette M; Morrow, A Leslie; Jones, Sara R; Kash, Thomas L

    2015-12-01

    Chronic alcohol consumption and withdrawal leads to anxiety, escalated alcohol drinking behavior, and alcohol dependence. Alterations in the function of key structures within the cortico-limbic neural circuit have been implicated in underlying the negative behavioral consequences of chronic alcohol exposure in both humans and rodents. Here, we used chronic intermittent ethanol vapor exposure (CIE) in male C57BL/6J mice to evaluate the effects of chronic alcohol exposure and withdrawal on anxiety-like behavior and basal synaptic function and neuronal excitability in prefrontal cortical and extended amygdala brain regions. Forty-eight hours after four cycles of CIE, mice were either assayed in the marble burying test (MBT) or their brains were harvested and whole-cell electrophysiological recordings were performed in the prelimbic and infralimbic medial prefrontal cortex (PLC and ILC), the lateral and medial central nucleus of the amygdala (lCeA and mCeA), and the dorsal and ventral bed nucleus of the stria terminalis (dBNST and vBNST). Ethanol-exposed mice displayed increased anxiety in the MBT compared to air-exposed controls, and alterations in neuronal function were observed in all brain structures examined, including several distinct differences between subregions within each structure. Chronic ethanol exposure induced hyperexcitability of the ILC, as well as a shift toward excitation in synaptic drive and hyperexcitability of vBNST neurons; in contrast, there was a net inhibition of the CeA. This study reveals extensive effects of chronic ethanol exposure on the basal function of cortico-limbic brain regions, suggests that there may be complex interactions between these regions in the regulation of ethanol-dependent alterations in anxiety state, and highlights the need for future examination of projection-specific effects of ethanol in cortico-limbic circuitry.

  4. Effects of chronic ethanol exposure on neuronal function in the prefrontal cortex and extended amygdala.

    Science.gov (United States)

    Pleil, Kristen E; Lowery-Gionta, Emily G; Crowley, Nicole A; Li, Chia; Marcinkiewcz, Catherine A; Rose, Jamie H; McCall, Nora M; Maldonado-Devincci, Antoniette M; Morrow, A Leslie; Jones, Sara R; Kash, Thomas L

    2015-12-01

    Chronic alcohol consumption and withdrawal leads to anxiety, escalated alcohol drinking behavior, and alcohol dependence. Alterations in the function of key structures within the cortico-limbic neural circuit have been implicated in underlying the negative behavioral consequences of chronic alcohol exposure in both humans and rodents. Here, we used chronic intermittent ethanol vapor exposure (CIE) in male C57BL/6J mice to evaluate the effects of chronic alcohol exposure and withdrawal on anxiety-like behavior and basal synaptic function and neuronal excitability in prefrontal cortical and extended amygdala brain regions. Forty-eight hours after four cycles of CIE, mice were either assayed in the marble burying test (MBT) or their brains were harvested and whole-cell electrophysiological recordings were performed in the prelimbic and infralimbic medial prefrontal cortex (PLC and ILC), the lateral and medial central nucleus of the amygdala (lCeA and mCeA), and the dorsal and ventral bed nucleus of the stria terminalis (dBNST and vBNST). Ethanol-exposed mice displayed increased anxiety in the MBT compared to air-exposed controls, and alterations in neuronal function were observed in all brain structures examined, including several distinct differences between subregions within each structure. Chronic ethanol exposure induced hyperexcitability of the ILC, as well as a shift toward excitation in synaptic drive and hyperexcitability of vBNST neurons; in contrast, there was a net inhibition of the CeA. This study reveals extensive effects of chronic ethanol exposure on the basal function of cortico-limbic brain regions, suggests that there may be complex interactions between these regions in the regulation of ethanol-dependent alterations in anxiety state, and highlights the need for future examination of projection-specific effects of ethanol in cortico-limbic circuitry. PMID:26188147

  5. Effects of Exposure to Heavy Particles on a Behavior Mediated by the Dopaminergic System

    Science.gov (United States)

    Rabin, B. M.; Joseph, J. A.; Shukitt-Hale, B.; McEwen, J.

    The effects of exposure to heavy particles on behaviors mediated by the central nervous system (CNS) are qualitatively different than the effects produced by exposure to other types of radiation. One behavior mediated by the CNS is the amphetamine-induced taste aversion, which is produced by pairing a novel tasting solution with injection of amphetamine. When the conditioning day is three days following irradiation, exposing rats to low doses of 56Fe particles (600 MeV/n or 1 GeV/n) eliminates the taste aversion produced by injection of amphetamine, which is dependent upon the integrity of the central dopaminergic system, but has no effect on the aversion produced by injection of lithium chloride which is mediated by the gastrointestinal system. In contrast to the effects obtained using heavy particles, exposing rats to 60Co gamma rays or to fission spectrum neutrons has no selective effect upon the acquisition of either amphetamine- or lithium chloride-induced taste aversions. When the conditioning day occurs four months following exposure to 1 GeV/n 56Fe particles, there is an enhancement of the amphetamine-induced taste aversion. The implications of these findings for approaches to risk assessment are considered

  6. A summary of two meta-analyses on neurobehavioural effects due to occupational lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Seeber, Andreas; Meyer-Baron, Monika; Schaeper, Michael [Institut fuer Arbeitsphysiologie, Universitaet Dortmund (Germany)

    2002-04-01

    The conclusions from published results about neurotoxic effects of inorganic lead exposures <700 {mu}g lead/l blood are contradictory at present. Effects measured by neurobehavioural methods are evaluated differently as far as recommendations for a Biological Exposure Index (BEI) of occupational lead exposure are concerned. Arguments against the German BEI of 400 {mu}g/l were put forward in new publications, and discussion of the issues is the aim of this article. It summarizes two different meta-analytical reviews on neurobehavioural effects in order to show the main tendencies of 24 selected publications on the matter. Calculations on effect sizes are compiled for 12 tests analysed in two meta-analyses and of ten tests analysed in one of the meta-analyses. The survey of six tests of learning and memory gives hints on impairments measured with two tests, covering Logical Memory and Visual Reproduction. The survey of seven tests of attention and visuospatial information processing describes impairments in four tests, namely Simple Reaction, Attention Test d2, Block Design, and Picture Completion. The survey of four tests for psychomotor functions shows impairments for three tests, namely Santa Ana, Grooved Pegboard, and Eye-hand Coordination. These test results provide evidence for subtle deficits being associated with average blood lead levels between 370 and 520 {mu}g/l. In evaluating the adversity of such effects it is concluded that the results of both meta-analytical reviews support the recommendation for the German BEI. (orig.)

  7. Prenatal Exposures to Multiple Thyroid Hormone Disruptors: Effects on Glucose and Lipid Metabolism.

    Science.gov (United States)

    Molehin, Deborah; Dekker Nitert, Marloes; Richard, Kerry

    2016-01-01

    Background. Thyroid hormones (THs) are essential for normal human fetal development and play a major role in the regulation of glucose and lipid metabolism. Delivery of TH to target tissues is dependent on processes including TH synthesis, transport, and metabolism. Thyroid hormone endocrine disruptors (TH-EDCs) are chemical substances that interfere with these processes, potentially leading to adverse pregnancy outcomes. Objectives. This review focuses on the effects of prenatal exposures to combinations of TH-EDCs on fetal and neonatal glucose and lipid metabolism and also discusses the various mechanisms by which TH-EDCs interfere with other hormonal pathways. Methods. We conducted a comprehensive narrative review on the effects of TH-EDCs with particular emphasis on exposure during pregnancy. Discussion. TH imbalance has been linked to many metabolic processes and the effects of TH imbalance are particularly pronounced in early fetal development due to fetal dependence on maternal TH for proper growth and development. The pervasive presence of EDCs in the environment results in ubiquitous exposure to either single or mixtures of EDCs with deleterious effects on metabolism. Conclusions. Further evaluation of combined effects of TH-EDCs on fetal metabolic endpoints could improve advice provided to expectant mothers. PMID:26989557

  8. Prenatal Exposures to Multiple Thyroid Hormone Disruptors: Effects on Glucose and Lipid Metabolism

    Directory of Open Access Journals (Sweden)

    Deborah Molehin

    2016-01-01

    Full Text Available Background. Thyroid hormones (THs are essential for normal human fetal development and play a major role in the regulation of glucose and lipid metabolism. Delivery of TH to target tissues is dependent on processes including TH synthesis, transport, and metabolism. Thyroid hormone endocrine disruptors (TH-EDCs are chemical substances that interfere with these processes, potentially leading to adverse pregnancy outcomes. Objectives. This review focuses on the effects of prenatal exposures to combinations of TH-EDCs on fetal and neonatal glucose and lipid metabolism and also discusses the various mechanisms by which TH-EDCs interfere with other hormonal pathways. Methods. We conducted a comprehensive narrative review on the effects of TH-EDCs with particular emphasis on exposure during pregnancy. Discussion. TH imbalance has been linked to many metabolic processes and the effects of TH imbalance are particularly pronounced in early fetal development due to fetal dependence on maternal TH for proper growth and development. The pervasive presence of EDCs in the environment results in ubiquitous exposure to either single or mixtures of EDCs with deleterious effects on metabolism. Conclusions. Further evaluation of combined effects of TH-EDCs on fetal metabolic endpoints could improve advice provided to expectant mothers.

  9. A magnetic field exposure facility for evaluation of animal carcinogenicity.

    Science.gov (United States)

    Maruvada, P S; Harvey, S M; Jutras, P; Goulet, D; Mandeville, R

    2000-09-01

    Several animal studies have been carried out at the Institut Armand Frappier (IAF) to determine whether chronic exposure to 60 Hz linearly polarized sinusoidal magnetic fields might increase the risk of cancer development of female Fisher rats. The magnetic field exposure facility was developed to meet the requirements of the study protocol for chronic exposure of large number of animals to field intensities of sham < 0.2 microT, 2 microT, 20 microT, 200 microT, and 2000 microT. At each exposure level, including sham, the animals are distributed in a group of four exposure units. Each exposure unit contains two exposure volumes having uniform distribution of magnetic fields for the animals, while the magnetic field external to the unit falls off rapidly due to the "figure-eight" coil topography used. A program of "shake down" tests, followed by verification and calibration of the exposure facility, was carried out prior to starting the animal experiments. Continuous monitoring of the magnetic field and other environmental parameters was an important part in the overall quality assurance program adopted.

  10. Combined effect of radon exposure and smoking and their interaction in Czech studies of lung cancer

    International Nuclear Information System (INIS)

    The aim is to compare lung cancer risks from radon in smoking categories in Czech residential radon and uranium miners studies and to evaluate interactions between smoking and radon exposure. The residential and occupational studies are based on one hospital based case-control study and three case-control studies nested within cohort studies, two among uranium miners and one in the general population in a radon prone area. Controls in the nested studies are individually matched by sex, age and year of birth. Smoking data were collected in person or from relatives of deceased subjects. In the occupational studies, some smoking data were obtained from medical files. Radon exposures were based on measurements of radon in houses by open track detectors LR115 in the radon prone area and by closed detectors and electrets in the hospital based study. Exposures in uranium mines were based on extensive measurements and personal dosimetry. The analyses are based on conditional logistic regression with linear dependence of the risk on radon exposure adjusted for smoking. The study resulted in 300 cases and 1035 controls in the residential study and 672 cases and 1491 controls in the study of uranium miners. The dependence of lung cancer risk on radon exposure adjusted for smoking was not substantially different from analyses when smoking was ignored and reflected mainly the risk among smokers. However, the excess relative risk per unit exposure among non-smokers was 3-10 fold higher in comparison to that in smokers. The relative risk from radon among non-smokers was consistently higher in the occupational and residential studies, reflecting probably differences in lung morphometry, clearence and unattached fraction of radon progeny in houses of non-smokers. Risks from combined effects are substantially lower than the risk derived from the multiplicative model, but consistent with the additive model. (author)

  11. Are the current Australian sun exposure guidelines effective in maintaining adequate levels of 25-hydroxyvitamin D?

    Science.gov (United States)

    Kimlin, Michael; Sun, Jiandong; Sinclair, Craig; Heward, Sue; Hill, Jane; Dunstone, Kimberley; Brodie, Alison

    2016-01-01

    An adequate vitamin D status, as measured by serum 25-hydroxyvitamin D (25(OH)D) concentration, is important in humans for maintenance of healthy bones and muscle function. Serum 25(OH)D concentration was assessed in participants from Melbourne, Australia (37.81S, 144.96E), who were provided with the current Australian guidelines on sun exposure for 25(OH)D adequacy (25(OH)D ≥50 nmol/L). Participants were interviewed in February (summer, n=104) and August (winter, n=99) of 2013. Serum 25(OH)D concentration was examined as a function of measures of sun exposure and sun protection habits with control of key characteristics such as dietary intake of vitamin D, body mass index (BMI) and skin colour, that may modify this relationship. The mean 25(OH)D concentration in participants who complied with the current sun exposure guidelines was 67.3 nmol/L in summer and 41.9 nmol/L in winter. At the end of the study, 69.3% of participants who complied with the summer sun exposure guidelines were 25(OH)D adequate, while only 27.6% of participants who complied with the winter sun exposure guidelines were 25(OH)D adequate at the end of the study. The results suggest that the current Australian guidelines for sun exposure for 25(OH)D adequacy are effective for most in summer and ineffective for most in winter. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

  12. Effect of Second-Hand Smoke Exposure on Lung Function among Non-Smoking Korean Women.

    Directory of Open Access Journals (Sweden)

    Youngmee Kim

    2013-12-01

    Full Text Available Previous literature has implicated that there might be an individual susceptibility difference in terms of race/ethnicity and gender in response to second hand smoke (SHS exposure. This study was done to examine the effect of SHS exposure on lung function in non-smoking Korean women.This cross-sectional study was conducted using the Korea National Health and Nutrition Examination Survey (KNHANES from 2008-2011. A total of 2,513 female participants, age 40 yr and older, with no respiratory symptoms or prior lung diseases, were included in this study. Participants' smoking status was examined using both self-reported history and measurement of urinary cotinine level. Lung function was assessed using spirometry data, including FVC and FEV1. T-test and Chi-square tests were performed to compare diverse variables between groups. Analysis of covariance (ANCOVA adjusted for age, height, alcohol consumption, and level of exercise was used to see any statistical differences in lung function parameters between non-SHS exposed and SHS-exposed groups.Among 2,513 non-smoking females, 767 (30.5% were SHS-exposed. The urinary cotinine levels clearly distinguished SHS exposure, and the mean urinary cotinine levels were 7.1±0.4 and 11±0.7 in non-SHS exposed group vs. SHS-exposed group, respectively (P < 0.001. Urinary cotinine levels were correlated with duration of SHS exposure. However, both groups had normal lung function and there was no significant difference between the two groups in lung function.Urinary cotinine is a valuable marker of SHS exposure. Korean women may have higher tolerance for SHS exposure-induced lung function decline.

  13. Effects of prolonged exposure to perchlorate on thyroid and reproductive function in zebrafish

    Science.gov (United States)

    Mukhi, S.; Patino, R.

    2007-01-01

    The objectives of this study were to determine the effects of prolonged exposure to perchlorate on (1) thyroid status and reproductive performance of adult zebrafish (Danio rerio) and (2) F1 embryo survival and early larval development. Using a static-renewal procedure, mixed sex populations of adult zebrafish were exposed to 0, 10, and 100 mg/l nominal concentrations of waterborne perchlorate for 10 weeks. Thyroid histology was qualitatively assessed, and females and males were separated and further exposed to their respective treatments for six additional weeks. Eight females in each tank replicate (n = 3) were paired weekly with four males from the same respective treatment, and packed-egg (spawn) volume (PEV) was measured each of the last five weeks. At least once during weeks 14-16 of exposure, other end points measured included fertilization rate, fertilized egg diameter, hatching rate, standard length, and craniofacial development of 4-day-postfertilization larvae and thyroid hormone content of 3.5-h embryos and of exposed mothers. At 10 weeks of exposure, perchlorate at both concentrations caused thyroidal hypertrophy and colloid depletion. A marked reduction in PEV was observed toward the end of the 6-week spawning period, but fertilization and embryo hatching rates were unaffected. Fertilized egg diameter and larval length were increased by parental exposure to perchlorate. Larval head depth was unaffected but the forward protrusion of the lower jaw-associated cartilage complexes, Meckel's and ceratohyal, was decreased. Exposure to both concentrations of perchlorate inhibited whole-body thyroxine content in mothers and embryos, but triiodothyronine content was unchanged. In conclusion, prolonged exposure of adult zebrafish to perchlorate not only disrupts their thyroid endocrine system but also impairs reproduction and influences early F1 development. ?? 2007 Oxford University Press.

  14. Effects of titanium dioxide nanoparticle exposure in Mytilus galloprovincialis gills and digestive gland.

    Science.gov (United States)

    Gornati, Rosalba; Longo, Arturo; Rossi, Federica; Maisano, Maria; Sabatino, Giuseppe; Mauceri, Angela; Bernardini, Giovanni; Fasulo, Salvatore

    2016-08-01

    Despite the wide use of nanoscale materials in several fields, some aspects of the nanoparticle behavior have to be still investigated. In this work, we faced the aspect of environmental effects of increasing concentrations of TiO2NPs using the Mytilus galloprovincialis as an animal model and carrying out a multidisciplinary approach to better explain the results. Bioaccumulation suggested that the gills and digestive gland are the most sensitive organs to TiO2NP exposure. Histological observations have evidenced an altered tissue organization and a consistent infiltration of hemocytes, as a consequence of the immune system activation, even though an increase in lipid peroxidation is uncertain and DNA damage became relevant only at high exposure dose (10 mg/L) or for longer exposure time (96 h). However, the over expression of SOD1 mRNA strengthen the concept that the toxicity of TiO2NPs could occur indirectly by ROS production. TEM analysis showed the presence of multilamellar bodies, RER fragmentation, and cytoplasmic vacuolization within relevant presence of dense granules, residual bodies, and lipid inclusions. These findings support the evidence of an initial inflammatory response by the cells of the target organs leading to apoptosis. In conclusion, we can state that certainly the exposure to TiO2NPs has affected our animal model from cellular to molecular levels. Interestingly, the same responses are caused by lower TiO2NP concentration and longer exposure time as well as higher doses and shorter exposure. We do not know if some of the conditions detected are reversible, then further studies are required to clarify this aspect. PMID:26846715

  15. Effect of acute ozone exposure on the proteinase-antiproteinase balance in the rat lung

    International Nuclear Information System (INIS)

    Lung disease may result from a persisting proteinase excess or a depletion of antiproteinase in pulmonary parenchyma. We investigated the in vivo effect of a 48-hr exposure to ozone at 0.5, 1.0, or 1.5 ppm on proteinase and antiproteinase activity of rat lungs. Elastase inhibitory capacities of serum, lung tissue, and airway washings were measured as indicators of antielastase activity. Trypsin inhibitory capacity was measured using an esterolytic procedure. Proteinase was measured as radioactive release from a 14C-globin substrate. The 48-hr exposures to O3 at levels up to 1 ppm produced concentration-dependent decreases of 35-80% of antiproteinase activities in serum and in lung tissue. However, exposure to 1.5 ppm O3 resulted in no decrease in antiproteinase activities. Acid proteinase activities (pH 4.2) were increased 65-120% by exposure to 1 or 1.5 ppm O3, which correlated with inflammatory cells noted histologically. At 1.5 ppm O3, pulmonary edema and hemorrhage were noted in histologic sections. These changes led to a flooding of the alveoli with up to 40 times normal protein levels and a greater than fivefold increase in airway antiproteinase. These data suggest that serum and soluble lung tissue antiproteinase activity decreased upon exposure to low levels of ozone. However, if O3 exposure is high enough to produce pulmonary hemorrhage, antiproteinase may increase following serum exudation. These changes may be important in the development of ozone-induced lung diseases, especially emphysema

  16. Gestational Atrazine Exposure: Effects on Male Reproductive Development and Metabolite Distribution in the Dam, Fetus, and Neonate

    Science.gov (United States)

    Few studies have investigated the long-term effects of atrazine (ATR)following in utero exposure. We evaluated the effects of gestational exposure of Sprague Dawley dams to ATR (0, 1, 5.20, or 100 mg/Kg-d) on the reproductive development of male offspring. We also quantified the...

  17. Effects of Perinatal Exposure to PCBs on Neuropsychological Functions in the Rotterdam Cohort at 9 Years of Age

    NARCIS (Netherlands)

    Vreugdenhil, H.J.I.; Emmen, H.H.; Mulder, P.G.H.; Weisglas-Kuperus, N.

    2004-01-01

    PCBs are known for their neurotoxic properties, especially on the developing brain. To increase insight into the neurotoxic effects of PCB exposure, the authors studied the effects of perinatal exposure to environmental levels of these compounds on different neuropsychological domains. In 9-year-old

  18. EFFECTS OF TRITIUM EXPOSURE ON UHMW-PE, PTFE, AND VESPEL

    Energy Technology Data Exchange (ETDEWEB)

    Clark, E; Kirk Shanahan, K

    2006-05-31

    Samples of three polymers, Ultra-High Molecular Weight Polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, also known as Teflon{reg_sign}), and Vespel{reg_sign} polyimide were exposed to 1 atmosphere of tritium gas at ambient temperature for varying times up to 2.3 years in closed containers. Sample mass and size measurements (to calculate density), spectra-colorimetry, dynamic mechanical analysis (DMA), and Fourier-transform infrared spectroscopy (FT-IR) were employed to characterize the effects of tritium exposure on these samples. Changes of the tritium exposure gas itself were characterized at the end of exposure by measuring total pressure and by mass spectroscopic analysis of the gas composition. None of the polymers exhibited significant changes of density. The color of initially white UHMW-PE and PTFE dramatically darkened to the eye and the color also significantly changed as measured by colorimetry. The bulk of UHMW-PE darkened just like the external surfaces, however the fracture surface of PTFE appeared white compared to the PTFE external surfaces. The white interior could have been formed while the sample was breaking or could reflect the extra tritium dose at the surface directly from the gas. The dynamic mechanical response of UHMW-PE was typical of radiation effects on polymers- an initial stiffening (increased storage modulus) and reduction of viscous behavior after three months exposure, followed by lowering of the storage modulus after one year exposure and longer. The storage modulus of PTFE increased through about nine months tritium exposure, then the samples became too weak to handle or test using DMA. Characterization of Vespel{reg_sign} using DMA was problematic--sample-to-sample variations were significant and no systematic change with tritium exposure could be discerned. Isotopic exchange and incorporation of tritium into UHMW-PE (exchanging for protium) and into PTFE (exchanging for fluorine) was observed by FT-IR using an attenuated

  19. Evaluating exposure and potential effects on honeybee brood (Apis mellifera) development using glyphosate as an example.

    Science.gov (United States)

    Thompson, Helen M; Levine, Steven L; Doering, Janine; Norman, Steve; Manson, Philip; Sutton, Peter; von Mérey, Georg

    2014-07-01

    This study aimed to develop an approach to evaluate potential effects of plant protection products on honeybee brood with colonies at realistic worst-case exposure rates. The approach comprised 2 stages. In the first stage, honeybee colonies were exposed to a commercial formulation of glyphosate applied to flowering Phacelia tanacetifolia with glyphosate residues quantified in relevant matrices (pollen and nectar) collected by foraging bees on days 1, 2, 3, 4, and 7 postapplication and glyphosate levels in larvae were measured on days 4 and 7. Glyphosate levels in pollen were approximately 10 times higher than in nectar and glyphosate demonstrated rapid decline in both matrices. Residue data along with foraging rates and food requirements of the colony were then used to set dose rates in the effects study. In the second stage, the toxicity of technical glyphosate to developing honeybee larvae and pupae, and residues in larvae, were then determined by feeding treated sucrose directly to honeybee colonies at dose rates that reflect worst-case exposure scenarios. There were no significant effects from glyphosate observed in brood survival, development, and mean pupal weight. Additionally, there were no biologically significant levels of adult mortality observed in any glyphosate treatment group. Significant effects were observed only in the fenoxycarb toxic reference group and included increased brood mortality and a decline in the numbers of bees and brood. Mean glyphosate residues in larvae were comparable at 4 days after spray application in the exposure study and also following dosing at a level calculated from the mean measured levels in pollen and nectar, showing the applicability and robustness of the approach for dose setting with honeybee brood studies. This study has developed a versatile and predictive approach for use in higher tier honeybee toxicity studies. It can be used to realistically quantify exposure of colonies to pesticides to allow the

  20. Sun Exposure and Its Effects on Human Health: Mechanisms through Which Sun Exposure Could Reduce the Risk of Developing Obesity and Cardiometabolic Dysfunction

    Science.gov (United States)

    Fleury, Naomi; Geldenhuys, Sian; Gorman, Shelley

    2016-01-01

    Obesity is a significant burden on global healthcare due to its high prevalence and associations with chronic health conditions. In our animal studies, ongoing exposure to low dose ultraviolet radiation (UVR, found in sunlight) reduced weight gain and the development of signs of cardiometabolic dysfunction in mice fed a high fat diet. These observations suggest that regular exposure to safe levels of sunlight could be an effective means of reducing the burden of obesity. However, there is limited knowledge around the nature of associations between sun exposure and the development of obesity and cardiometabolic dysfunction, and we do not know if sun exposure (independent of outdoor activity) affects the metabolic processes that determine obesity in humans. In addition, excessive sun exposure has strong associations with a number of negative health consequences such as skin cancer. This means it is very important to “get the balance right” to ensure that we receive benefits without increasing harm. In this review, we detail the evidence around the cardiometabolic protective effects of UVR and suggest mechanistic pathways through which UVR could be beneficial. PMID:27727191

  1. The effect of commuting microenvironment on commuter exposures to vehicular emission in Hong Kong

    Science.gov (United States)

    Chan, L. Y.; Chan, C. Y.; Qin, Y.

    Vehicular exhaust emission has gradually become the major air pollution source in modern cities and traffic related exposure is found to contribute significantly to total human exposure level. A comprehensive survey was conducted from November 1995 to July 1996 in Hong Kong to assess the effect of traffic-induced air pollution inside different commuting microenvironments on commuter exposure. Microenvironmental monitoring is performed for six major public commuting modes (bus, light bus, MTR, railway, tram, ferry), plus private car and roadside pavement. Traffic-related pollutants, CO, NO x, THC and O 3 were selected as the target pollutants. The results indicate that commuter exposure is highly influenced by the choice of commuting microenvironment. In general, the exposure level in decreasing order of measured pollutant level for respective commuting microenvironments are: private car, the group consisting light bus, bus, tram and pavement, MTR and train, and finally ferry. In private car, the CO level is several times higher than that in the other microenvironments with a trip averaged of 10.1 ppm and a maximum of 24.9 ppm. Factors such as the body position of the vehicle, intake point of the ventilation system, fuel used, ventilation, transport mode, road and driving conditions were used in the analysis. Inter-microenvironment, intra-microenvironment and temporal variation of CO concentrations were used as the major indicator. The low body position and low intake point of the ventilation system of the private car are believed to be the cause of higher intake of exhaust of other vehicles and thus result in high pollution level in this microenvironment. Compared with other metropolis around the world and the Hong Kong Air Quality Objectives (HKAQO), exposure levels of commuter to traffic-related air pollution in Hong Kong are relatively low for most pollutants measured. Only several cases of exceedence of HKAQO by NO 2 were recorded. The strong prevailing wind

  2. The effects of in utero bisphenol A exposure on reproductive capacity in several generations of mice

    International Nuclear Information System (INIS)

    In utero bisphenol A (BPA) exposure affects reproductive function in the first generation (F1) of mice; however, not many studies have examined the reproductive effects of BPA exposure on subsequent generations. In this study, pregnant mice (F0) were orally dosed with vehicle, BPA (0.5, 20, and 50 μg/kg/day) or diethylstilbestrol (DES; 0.05 μg/kg/day) daily from gestation day 11 until birth. F1 females were used to generate the F2 generation, and F2 females were used to generate the F3 generation. Breeding studies at the ages of 3, 6, and 9 months were conducted to evaluate reproductive capacity over time. Further, studies were conducted to evaluate pubertal onset, litter size, and percentage of dead pups; and to calculate pregnancy rate, and mating, fertility, and gestational indices. The results indicate that BPA exposure (0.5 and 50 μg/kg/day) significantly delayed the age at vaginal opening in the F3 generation compared to vehicle control. Both DES (0.05 μg/kg/day) and BPA (50 μg/kg/day) significantly delayed the age at first estrus in the F3 generation compared to vehicle control. BPA exposure reduced gestational index in the F1 and F2 generations compared to control. Further, BPA exposure (0.5 μg/kg/day) compromised the fertility index in the F3 generation compared to control. Finally, in utero BPA exposure reduced the ability of female mice to maintain pregnancies as they aged. Collectively, these data suggest that BPA exposure affects reproductive function in female mice and that some effects may be transgenerational in nature. - Highlights: • In utero BPA delayed vaginal opening in the F3 generation compared to control. • In utero BPA delayed estrus in the F3 generation compared to control. • In utero BPA reduced the ability of F1 and F2 female mice to maintain pregnancies. • In utero BPA compromised the ability of F3 female mice to become pregnant. • Some effects of in utero BPA may be transgenerational in nature

  3. The effects of in utero bisphenol A exposure on reproductive capacity in several generations of mice

    Energy Technology Data Exchange (ETDEWEB)

    Ziv-Gal, Ayelet, E-mail: zivgal1@illinois.edu; Wang, Wei, E-mail: weiwang2@illinois.edu; Zhou, Changqing, E-mail: czhou27@illinois.edu; Flaws, Jodi A., E-mail: jflaws@illinois.edu

    2015-05-01

    In utero bisphenol A (BPA) exposure affects reproductive function in the first generation (F1) of mice; however, not many studies have examined the reproductive effects of BPA exposure on subsequent generations. In this study, pregnant mice (F0) were orally dosed with vehicle, BPA (0.5, 20, and 50 μg/kg/day) or diethylstilbestrol (DES; 0.05 μg/kg/day) daily from gestation day 11 until birth. F1 females were used to generate the F2 generation, and F2 females were used to generate the F3 generation. Breeding studies at the ages of 3, 6, and 9 months were conducted to evaluate reproductive capacity over time. Further, studies were conducted to evaluate pubertal onset, litter size, and percentage of dead pups; and to calculate pregnancy rate, and mating, fertility, and gestational indices. The results indicate that BPA exposure (0.5 and 50 μg/kg/day) significantly delayed the age at vaginal opening in the F3 generation compared to vehicle control. Both DES (0.05 μg/kg/day) and BPA (50 μg/kg/day) significantly delayed the age at first estrus in the F3 generation compared to vehicle control. BPA exposure reduced gestational index in the F1 and F2 generations compared to control. Further, BPA exposure (0.5 μg/kg/day) compromised the fertility index in the F3 generation compared to control. Finally, in utero BPA exposure reduced the ability of female mice to maintain pregnancies as they aged. Collectively, these data suggest that BPA exposure affects reproductive function in female mice and that some effects may be transgenerational in nature. - Highlights: • In utero BPA delayed vaginal opening in the F3 generation compared to control. • In utero BPA delayed estrus in the F3 generation compared to control. • In utero BPA reduced the ability of F1 and F2 female mice to maintain pregnancies. • In utero BPA compromised the ability of F3 female mice to become pregnant. • Some effects of in utero BPA may be transgenerational in nature.

  4. Collective effects and their control at the Spallation Neutron Source Ring

    Energy Technology Data Exchange (ETDEWEB)

    Wei, J.; Blaskiewicz, M.; Brodowski, J.; Cameron, P.; Davino, D.; Fedotov, A.; Hahn, H.; Hseuh, H.; Lee, Y.Y.; Raparia, D.; Zhang, S.Y.; Danilov, V.; Henderson, S.; Holmes, J.; Wang, J.G.; Furman, M.; Pivi, M.; Kurennoy, S.; Macek, R.

    2002-06-01

    The SNS ring is designed to accumulate up to 2 x 10{sup 14} protons of 1 GeV kinetic energy at a repetition rate of 60 Hz [1]. Dominant collective effects include space charge and halo generation, impedance-driven instabilities, impedance-induced closed-orbit deviation and heating, and electron cloud.

  5. Effects of benzophenone-3 exposure on endocrine disruption and reproduction of Japanese medaka (Oryzias latipes)—A two generation exposure study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sujin; Jung, Dawoon [School of Public Health, Seoul National University, Seoul 151-742 (Korea, Republic of); Kho, Younglim [Department of Health, Environment and Safety, Eulji University, Seongnam 461-713 (Korea, Republic of); Choi, Kyungho, E-mail: kyungho@snu.ac.kr [School of Public Health, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2014-10-15

    Highlights: • Exposure to BP-3 led to adverse reproduction effects on Japanese medaka at 26 μg/L. • Changes in sex hormones and steroidogenic gene transcription were observed. • Parental exposure to BP-3 influenced on the growth of second generation fish. - Abstract: Benzophenone-3 (BP-3) has been widely used in sunscreens and cosmetics to protect human skin from the harmful effects of UV irradiation. While BP-3 has been frequently detected in surface waters, sediments and biota, only limited information is available on its in vivo toxicity, particularly in fish. In the present study the endocrine disrupting capacity of BP-3 and its underlying mechanisms were investigated using Japanese medaka (Oryzias latipes). Adult Japanese medaka pairs (F0) were exposed to 0, 4.7, 8.4, 26, or 90 μg/L (or 0, 15, 50, 150, or 500 μg/L of BP-3 based on nominal concentration) for 14 d and its effects on sex steroid hormones, and transcription of various associated genes were determined. Following additional 14 d of exposure, the F1 eggs reproduced were counted and were further exposed to 0, 5.4, 12, or 30 μg/L of BP-3 (or 0, 15, 50, or 150 μg/L based on nominal concentrations) until 30 d after hatching. Chemical analysis of the exposed media confirmed transformation of BP-3 to benzophenone-1 (BP-1), a more potent estrogen agonist. After 14 d of the adult fish exposure, plasma concentrations of testosterone (T) significantly increased in male fish. The 17β-estradiol (E2) to T (E2/T) ratio showed significant decreases in both male and female fish. Overall down-regulation of gonadal steroidogenic genes such as star, cyp11a, cyp17, hsd3b, hsd17b3, and cyp19a was also observed. After 28 d of exposure, the daily average egg reproduction per female was significantly reduced at 26 μg/L of BP-3. However, hatchability of F1 eggs was not affected by continuous exposure. After continued exposure until 30 dph, juvenile fish showed concentration-dependent decrease of condition factor

  6. STUDIES CONCERNING THE EFFECT OF GAMMA RADIATION AND MAGNETIC FIELD EXPOSURE ON GLADIOLUS

    Directory of Open Access Journals (Sweden)

    M CANTOR

    2003-04-01

    Full Text Available Gladiolus (Gladiolus sp. is one of the most floral species cultivated over in the world and in Romania. There are many studies concerning the effect of gamma radiation on ornamental plants but little is known about the synergetic effect of gamma radiation and exposure to magnetic fields on Gladiolus. In our investigation we have tested the effect of gamma irradiation and magnetic field exposure of gladiolus corms and cormels of the cultivars: Her Majesty, Applause and Speranţa. The corms and cormels were irradiated for 72 hrs with 137 Cs gamma source on cylindrical exposure geometry. At medium dose of 1 Gy has been accumulated for each corm and cormel. For each variety we used 10 corms and 30 cormels in five variants. The comportment of various varieties was evaluated by recording the following characteristics: length of roots and growth tip. Significant effect was obtained at the variants which was irradiated with 1 Gy gamma radiation and 3 Gauss magnetic fields.

  7. Effects of sodium pentaborate pentahydrate exposure on Chlorella vulgaris growth, chlorophyll content, and enzyme activities.

    Science.gov (United States)

    Chen, Xueqing; Pei, Yuansheng

    2016-10-01

    Sodium pentaborate pentahydrate (SPP) is a rare mineral. In this study, SPP was synthesized from boric acid and borax through low-temperature crystallization, and its effects on the growth of the alga, Chlorella vulgaris (C. vulgaris) were assessed. The newly synthesized SPP was characterized by chemical analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, and differential thermal analysis. The changes in C. vulgaris growth, chlorophyll content, and enzyme activities upon exposure to SPP for 168h were evaluated. Results showed that SPP treatment was detrimental to C. vulgaris growth during the first 24-120h of exposure. The harmful effects, however, diminished over time (168h), even at an effective medium concentration of 226.37mg BL(-1) (the concentration of boron applied per liter of culture medium). A similar trend was observed for chlorophyll content (chlorophyll a and b) and indicated that the photosynthesis of C. vulgaris was not affected and that high levels of SPP may even promote chlorophyll synthesis. Superoxide dismutase and catalase activities of C. vulgaris increased during 24-120h exposure to SPP, but these activities gradually decreased as culture time progressed. In other words, the initial detrimental effects of synthetic SPP on C. vulgaris were temporary and reversible. This research provides a scientific basis for applications of SPP in the environment. PMID:27367150

  8. In Utero Caffeine Exposure Induces Transgenerational Effects on the Adult Heart

    Science.gov (United States)

    Fang, Xiefan; Poulsen, Ryan R.; Rivkees, Scott A.; Wendler, Christopher C.

    2016-01-01

    Each year millions of pregnant woman are exposed to caffeine, which acts to antagonize adenosine action. The long-term consequences of this exposure on the developing fetus are largely unknown, although in animal models we have found adverse effects on cardiac function. To assess if these effects are transmitted transgenerationally, we exposed pregnant mice to caffeine equivalent to 2–4 cups of coffee at two embryonic stages. Embryos (F1 generation) exposed to caffeine early from embryonic (E) day 6.5–9.5 developed a phenotype similar to dilated cardiomyopathy by 1 year of age. Embryos exposed to caffeine later (E10.5–13.5) were not affected. We next examined the F2 generation and F3 generation of mice exposed to caffeine from E10.5–13.5, as this coincides with germ cell development. These F2 generation adult mice developed a cardiac phenotype similar to hypertrophic cardiomyopathy. The F3 generation exhibited morphological changes in adult hearts, including increased mass. This report shows that in utero caffeine exposure has long-term effects into adulthood and that prenatal caffeine exposure can exert adverse transgenerational effects on adult cardiac function. PMID:27677355

  9. Some Behavioral Effects of Exposure to Low Doses of Fe-56 Particles

    Science.gov (United States)

    Rabin, Bernard M.; Joseph, James A.; Shukitt-Hale, Barbara

    1999-01-01

    Future missions in space (such as a mission to Mars) will involve long-term travel beyond the magnetic field of the Earth. As a result, astronauts will be exposed to radiation qualities and doses that differ from those experienced in low earth orbit, including exposure to heavy particles, such as Fe-56, which are a component of cosmic rays. Although the hazards of exposure to heavy particles are often minimized, they can affect neural functioning, and as a consequence, behavior. Unless the effects of exposure to cosmic rays can somehow be reduced, their effects on the brain throughout long duration flights could be disastrous. In the extreme case, it is possible that the effects of cosmic rays on space travelers could result in symptomatology resembling that of Alzheimer's or Parkinson's diseases or of advancing age, including significant cognitive and/or motor impairments. Because successful operations in space depend in part on the performance capabilities of astronauts, such impairments could jeopardize their ability to satisfy mission requirements, as well as have long-term consequences on the health of astronauts. As such, understanding the nature and extent of this risk may be vital to the effective performance and possibly the survival of astronauts during future missions in space.

  10. Transgenerational effects of stress exposure on offspring phenotypes in apomictic dandelion.

    Directory of Open Access Journals (Sweden)

    Koen J F Verhoeven

    Full Text Available Heritable epigenetic modulation of gene expression is a candidate mechanism to explain parental environmental effects on offspring phenotypes, but current evidence for environment-induced epigenetic changes that persist in offspring generations is scarce. In apomictic dandelions, exposure to various stresses was previously shown to heritably alter DNA methylation patterns. In this study we explore whether these induced changes are accompanied by heritable effects on offspring phenotypes. We observed effects of parental jasmonic acid treatment on offspring specific leaf area and on offspring interaction with a generalist herbivore; and of parental nutrient stress on offspring root-shoot biomass ratio, tissue P-content and leaf morphology. Some of the effects appeared to enhance offspring ability to cope with the same stresses that their parents experienced. Effects differed between apomictic genotypes and were not always consistently observed between different experiments, especially in the case of parental nutrient stress. While this context-dependency of the effects remains to be further clarified, the total set of results provides evidence for the existence of transgenerational effects in apomictic dandelions. Zebularine treatment affected the within-generation response to nutrient stress, pointing at a role of DNA methylation in phenotypic plasticity to nutrient environments. This study shows that stress exposure in apomictic dandelions can cause transgenerational phenotypic effects, in addition to previously demonstrated transgenerational DNA methylation effects.

  11. Transgenerational effects of stress exposure on offspring phenotypes in apomictic dandelion.

    Science.gov (United States)

    Verhoeven, Koen J F; van Gurp, Thomas P

    2012-01-01

    Heritable epigenetic modulation of gene expression is a candidate mechanism to explain parental environmental effects on offspring phenotypes, but current evidence for environment-induced epigenetic changes that persist in offspring generations is scarce. In apomictic dandelions, exposure to various stresses was previously shown to heritably alter DNA methylation patterns. In this study we explore whether these induced changes are accompanied by heritable effects on offspring phenotypes. We observed effects of parental jasmonic acid treatment on offspring specific leaf area and on offspring interaction with a generalist herbivore; and of parental nutrient stress on offspring root-shoot biomass ratio, tissue P-content and leaf morphology. Some of the effects appeared to enhance offspring ability to cope with the same stresses that their parents experienced. Effects differed between apomictic genotypes and were not always consistently observed between different experiments, especially in the case of parental nutrient stress. While this context-dependency of the effects remains to be further clarified, the total set of results provides evidence for the existence of transgenerational effects in apomictic dandelions. Zebularine treatment affected the within-generation response to nutrient stress, pointing at a role of DNA methylation in phenotypic plasticity to nutrient environments. This study shows that stress exposure in apomictic dandelions can cause transgenerational phenotypic effects, in addition to previously demonstrated transgenerational DNA methylation effects.

  12. Neurodevelopmental effects of maternal nutritional status and exposure to methylmercury from eating fish during pregnancy.

    Science.gov (United States)

    Davidson, Philip W; Strain, J J; Myers, Gary J; Thurston, Sally W; Bonham, Maxine P; Shamlaye, Conrad F; Stokes-Riner, Abbie; Wallace, Julie M W; Robson, Paula J; Duffy, Emeir M; Georger, Lesley A; Sloane-Reeves, Jean; Cernichiari, Elsa; Canfield, Richard L; Cox, Christopher; Huang, Li Shan; Janciuras, Joanne; Clarkson, Thomas W

    2008-09-01

    Fish contain nutrients that promote optimal brain growth and development but also contain methylmercury (MeHg) that can have toxic effects. The present study tested the hypothesis that the intake of selected nutrients in fish or measures of maternal nutritional status may represent important confounders when estimating the effects of prenatal methylmercury exposure on child development. The study took place in the Republic of Seychelles, an Indian Ocean archipelago where fish consumption is high. A longitudinal cohort study design was used. A total of 300 mothers were enrolled early in pregnancy. Nutrients considered to be important for brain development were measured during pregnancy along with prenatal MeHg exposure. The children were evaluated periodically to age 30 months. There were 229 children with complete outcome and covariate data for analysis. The primary endpoint was the Bayley Scales of Infant Development-II (BSID-II), administered at 9 and 30 months of age. Combinations of four secondary measures of infant cognition and memory were also given at 5, 9 and 25 months. Cohort mothers consumed an average of 537 g of fish (nine meals containing fish) per week. The average prenatal MeHg exposure was 5.9 ppm in maternal hair. The primary analysis examined the associations between MeHg, maternal nutritional measures and children's scores on the BSID-II and showed an adverse association between MeHg and the mean Psychomotor Developmental Index (PDI) score at 30 months. Secondary analyses of the association between the PDI and only MeHg alone or nutritional factors alone showed only a borderline significant association between MeHg and the PDI at 30 months and no associations with nutritional factors. One experimental measure at 5 months of age was positively associated with iodine status, but not prenatal MeHg exposure. These findings suggest a possible confounding role of maternal nutrition in studies examining associations between prenatal MeHg exposures and

  13. Radiation exposure effects on the performance of an electrically trainable artificial neural network (ETANN)

    International Nuclear Information System (INIS)

    The authors present the effects of radiation exposure on an analog neural network device. The neural network implements a fully parallel architecture integrating 10,240 analog non-volatile synapses fabricated in a CMOS process. Graceful degradation of forward propagation performance analog non-volatile synapses fabricated in a CMOS process. Graceful degradation of forward propagation performance was observed in units that were exposed to absorbed doses of up to 26 Krads (Si) of 10 MeV electrons. The units were exposed without bias, except for that due to the floating gates. Single chip solutions to two pattern recognition problems representing two levels of difficulty are employed for testing. Post-irradiation-effects are observed over the following weeks after exposure due to latent charge trapping mechanism in the oxides of the non-volatile floating gate structures. They show that with the suitable algorithm and model, units with apparently permanent damage can be retrained to 100% recognition performance

  14. Effects of Copper Exposure on Photosynthesis and Growth of the Seagrass Cymodocea nodosa: An Experimental Assessment.

    Science.gov (United States)

    Llagostera, Izaskun; Cervantes, Daniel; Sanmartí, Neus; Romero, Javier; Pérez, Marta

    2016-09-01

    Seagrasses form some of the most important coastal habitats. They may be negatively affected by trace metal contamination in certain coastal areas. In this study we experimentally assessed selected morphological and physiological traits of the seagrass Cymodocea nodosa, with increasing concentrations of copper (Cu) under controlled laboratory conditions. Short term (21 days) sub-lethal effects such as decreased maximum quantum yield, increased leaf necrosis and decreased shoot growth and shoot recruitment were clearly observed at the highest Cu exposure (5 mg L(-1)), while the effects were weaker at the intermediate concentration (2.5 mg L(-1)) and almost absent at the lowest concentration (1 mg L(-1)), indicating that this species is highly tolerant to copper exposure, at least in the short term. This fact could help to explain its distribution in relatively polluted coastal waters. PMID:27370819

  15. Cellular effects and gene expression after exposure to amorphous silica nanoparticles in vitro

    DEFF Research Database (Denmark)

    Foldbjerg, Rasmus; Beer, Christiane; Wang, Jing;

    Much of the concerns regarding engineered NP toxicity are based on knowledge from previous studies on ambient and environmental particles. E.g., the effects of exposure to silica dust particles have been studied intensively due to the carcinogenicity of crystalline silica. However, the increasing...... usage of engineered amorphous silica NPs has emphasized the need for further mechanistic insight to predict the consequences of exposure to the amorphous type of silica NPs. Recently, the parallelogram approach was proposed as a scheme to assess biological effects of nanomaterials (Krug and Wick, 2011...... global gene expression. Instead, up-regulated genes primarily related to lipid metabolism and biosynthesis whereas down-regulated genes were enriched in several processes, including transcription, cell junction and extra cellular matrix (ECM)-receptor interaction. Accordingly, our data suggest that...

  16. Effect of Temperature Cycling and Exposure to Extreme Temperatures on Reliability of Solid Tantalum Capacitors

    Science.gov (United States)

    Teverovsky, Alexander

    2007-01-01

    In this work, results of multiple temperature cycling (TC) (up to 1,000 cycles) of different types of solid tantalum capacitors are analyzed and reported. Deformation of chip tantalum during temperature variations simulating reflow soldering conditions was measured to evaluate the possibility of the pop-corning effect in the parts. To simulate the effect of short-time exposures to solder reflow temperatures on the reliability of tantalum capacitors, several part types were subjected to multiple cycles (up to 100) between room temperature and 240 C with periodical measurements of electrical characteristics of the parts. Mechanisms of degradation caused by temperature cycling and exposure to high temperatures, and the requirements of MIL-PRF-55365 for assessment of the resistance of the parts to soldering heat are discussed.

  17. Effects of Pesticide Exposure on Embryonic Development and Hatchling Traits of Turtles

    Institute of Scientific and Technical Information of China (English)

    Baofeng WU; Liang LIANG; Liang MA; Weiguo DU

    2016-01-01

    Deltamethrin is a widespread environmental hormone with endocrine-disrupting properties, but its effect on embryonic development of reptiles is largely unexplored. We investigated the effects of deltamethrin on embryonic development and offspring traits in two turtle species, one with parchment-shelled eggs and the other with rigid-shelled eggs. Deltamethrin exposure during egg incubation did not affect hatching success and hatchling body size in either species. However, embryonic exposure to deltamethrin resulted in reduced hatchling locomotor performance in the red-eared slider turtle (Trachemys scripta) with parchment-shelled eggs, but not in the Chinese three-keeled pond turtle (Chinemys reevesii) with rigid-shelled eggs. These results suggest that parchment-shelled eggs are likely more vulnerable to deltamethrin than rigid-shelled eggs.

  18. Effect of Multi-Shot X-Ray Exposures in IFE Armor Materials

    Energy Technology Data Exchange (ETDEWEB)

    Latkowski, J F; Abbott, R P; Schmitt, R C; Bell, B K

    2004-12-10

    As part of the High Average Power Laser (HAPL) program the performance of tungsten as an armor material is being studied. While the armor would be exposed to neutrons, x-rays and ions within an inertial fusion energy (IFE) power plant, the thermomechanical effects are believed to dominate. Using a pulsed x-ray source, long-term exposures of tungsten have been completed at fluences that are of interest for the IFE application. Modeling is used in conjunction with experiments on the XAPPER x-ray damage facility in an effort to recreate the effects that would be expected in an operating IFE power plant. X-ray exposures have been completed for a variety of x-ray fluences and number of shots. Analysis of the samples suggests that surface roughening has a threshold that is very close to the fluences that reproduce the peak temperatures expected in an IFE armor material.

  19. Low-dose effect of developmental bisphenol A exposure on sperm count and behaviour in rats

    DEFF Research Database (Denmark)

    Hass, Ulla; Christiansen, Sofie; Boberg, Julie;

    2016-01-01

    /day. In the offspring, growth, sexual maturation, weights and histopathology of reproductive organs, oestrus cyclicity and sperm counts were assessed. Neurobehavioural development was investigated using a behavioural testing battery including tests for motor activity, sweet preference, anxiety and spatial learning....... Decreased sperm count was found at the lowest bisphenol A dose, that is 25 μg/kg/day, but not at the higher doses. Reproductive organ weight and histology were not affected and no behavioural effects were seen in male offspring. In the female offspring, exposure to 25 μg/kg bw/day bisphenol A dose resulted...... not significantly affected. In conclusion, the present study using a robust experimental study design, has shown that developmental exposure to 25 μg/kg bw/day bisphenol A can cause adverse effects on fertility (decreased sperm count), neurodevelopment (masculinization of spatial learning in females) and lead...

  20. Human inorganic mercury exposure, renal effects and possible pathways in Wanshan mercury mining area, China.

    Science.gov (United States)

    Li, Ping; Du, Buyun; Chan, Hing Man; Feng, Xinbin

    2015-07-01

    Rice can accumulate methylmercury (MeHg) and rice consumption is the main route of MeHg exposure for the local population in Guizhou, China. However, inorganic Hg (IHg) load in human body is not comprehensively studied in highly Hg polluted areas such as Hg mining areas. This study is designed to evaluate human IHg exposure, related renal effects and possible pathways in Wanshan Hg mining area, Guizhou, Southwest China. Residents lived within 3 km to the mine waste heaps showed high Urine Hg (UHg) concentrations and the geometrical means (Geomean) of UHg were 8.29, 5.13, and 10.3 μg/g Creatinine (Cr) at site A, D, and E, respectively. It demonstrated a gradient of UHg concentrations with the distance from the pollution sources. A significantly positive correlation between paired results for UHg concentrations and serum creatinine (SCr) was observed in this study, but not for UHg and blood urea nitrogen (BUN). There are significant increases of SCr in two quartiles with high UHg concentrations. The results indicated that human IHg exposure may cause impairment of renal function. By calculation of Probable Daily Intake from different routes, we found that dietary intake is the main pathway of IHg exposure for the local population, rather than inhalation of Hg vapor. PMID:25863593

  1. Effect of exposure to dust on lung function of cement factory workers.

    Science.gov (United States)

    Noor, H; Yap, C L; Zolkepli, O; Faridah, M

    2000-03-01

    Exposure to Portland cement dust has long been associated with the prevalence of respiratory symptoms and varying degrees of airway obstruction in man. Apart from respiratory diseases, it was also found to be the cause of lung and laryngeal cancer, gastrointestinal tumours and also dermatitis. This study was done to investigate the effect of dust exposure on ventilatory lung function of Portland cement factory workers in Rawang, Selangor. Spirometry tests of 62 male workers (exposed to total dust concentration of 10,180 micrograms/m3 and PM10 of 8049 micrograms/m3) and 70 subjects from UPM (exposed to mean total dust of 192 micrograms/m3 and PM10 of 177 micrograms/m3--controls) revealed significant differences in spirometry values between the groups. The workers showed i) significantly lower FEV1% and FEF25-75%, and higher FMFT, ii) reduced FEV1% with increasing level of dust exposure and iii) higher prevalence of respiratory symptoms. Therefore, we suggest that exposure to dust in the cement factory leads to higher incidence of respiratory symptoms and impaired lung function.

  2. Effects of pre- and postnatal combined exposure to Pb and Mn on brain development in rats

    Energy Technology Data Exchange (ETDEWEB)

    Chandra, S.V.; Murthy, R.C.; Saxena, D.K.; Lal, B.

    1983-01-01

    The effect of maternally administered lead (Pb 5.0 mg/kg) and/or manganese (Mn 6 mg/kg) on the brain growth and some biochemicals was investigated in 21 day old pups exposed during gestation and/or lactation. The pups continuously exposed to the mixture of Pb and Mn during pre- and postnatal life presented with significant alterations in the body, brain weights, contents of DNA, RNA, protein and accumulation of both the metals in the brain, the magnitude of these changes was greater in pups exposed to the mixture of Pb and Mn during gestation + lactation than observed in pups identically exposed during gestation only. Pups subjected to any regime of metal exposure during lactation were least affected as indicated by no changes in the brain growth and biochemical parameters. Accumulation of Pb in the brain increased several folds in the animals exposed to the mixture of Pb and Mn in comparison to that observed after exposure to Pb alone. These data suggest that exposure to the two metal ions during prenatal and early postnatal life is more injurious to the brain growth than the identical exposure during the lactation alone.

  3. Exposure to Weight-Stigmatizing Media: Effects on Exercise Intentions, Motivation, and Behavior.

    Science.gov (United States)

    Pearl, Rebecca L; Dovidio, John F; Puhl, Rebecca M; Brownell, Kelly D

    2015-01-01

    This study aimed to evaluate the impact of exposure to weight-stigmatizing media on exercise intentions, motivation, and behavior, as well as to examine the interaction between this exposure and past experiences with weight stigma. A community sample of 72 women were randomly assigned to view a brief weight-stigmatizing or neutral video. Participants' choice of taking the stairs versus the elevator was observed before they completed measures of exercise intentions, motivation, and behavior; psychological well-being; and experiences with weight stigma. A follow-up survey was sent to participants 1 week later that assessed exercise behavior and intentions. Frequency of past weight stigma correlated with worse psychological well-being and more controlled (versus autonomous) exercise motivation. Significant interactions were found between past weight-stigmatizing experiences and exposure to the weight-stigmatizing video for outcomes of exercise intentions, behavior, and drive for thinness. Participants in the stigma condition with higher frequency of past experiences reported greater exercise intentions and behavior, along with higher drive for thinness. Past experiences of weight stigma interact with exposure to weight-stigmatizing media to increase exercise intentions and behavior, although this effect is accompanied by a heightened drive for thinness that may increase risk for long-term negative health consequences.

  4. Tests for Gene-Environment Interactions and Joint Effects With Exposure Misclassification.

    Science.gov (United States)

    Boonstra, Philip S; Mukherjee, Bhramar; Gruber, Stephen B; Ahn, Jaeil; Schmit, Stephanie L; Chatterjee, Nilanjan

    2016-02-01

    The number of methods for genome-wide testing of gene-environment (G-E) interactions continues to increase, with the aim of discovering new genetic risk factors and obtaining insight into the disease-gene-environment relationship. The relative performance of these methods, assessed on the basis of family-wise type I error rate and power, depends on underlying disease-gene-environment associations, estimates of which may be biased in the presence of exposure misclassification. This simulation study expands on a previously published simulation study of methods for detecting G-E interactions by evaluating the impact of exposure misclassification. We consider 7 single-step and modular screening methods for identifying G-E interaction at a genome-wide level and 7 joint tests for genetic association and G-E interaction, for which the goal is to discover new genetic susceptibility loci by leveraging G-E interaction when present. In terms of statistical power, modular methods that screen on the basis of the marginal disease-gene relationship are more robust to exposure misclassification. Joint tests that include main/marginal effects of a gene display a similar robustness, which confirms results from earlier studies. Our results offer an increased understanding of the strengths and limitations of methods for genome-wide searches for G-E interaction and joint tests in the presence of exposure misclassification.

  5. Effects of low-level blast exposure on the nervous system: Is there really a controversy?

    Directory of Open Access Journals (Sweden)

    Gregory A Elder

    2014-12-01

    Full Text Available High-pressure blast waves can cause extensive CNS injury in humans. However, in combat settings such as Iraq and Afghanistan, lower level exposures associated with mild TBI (mTBI or subclinical exposure have been much more common. Yet controversy exists concerning what traits can be attributed to low-level blast, in large part due to the difficulty of distinguishing blast-related mTBI from post-traumatic stress disorder (PTSD. We describe how TBI is defined in humans and the problems posed in using current definitions to recognize blast-related mTBI. We next consider the problem of applying definitions of human mTBI to animal models, in particular that TBI severity in humans is defined in relation to alteration of consciousness at the time of injury, which typically cannot be assessed in animals. However, based on outcome assessments a condition of low-level blast exposure can be defined in animals that likely approximates human mTBI or subclinical exposure. We review blast injury modeling in animals noting that inconsistencies in experimental approach have contributed to uncertainty over the effects of low-level blast. Yet animal studies show that low-level blast pressure waves are transmitted to the brain. In brain low-level blast exposures cause behavioral, biochemical, pathological and physiological effects on the nervous system including the induction of PTSD-related behavioral traits in the absence of a psychological stressor. We review the relationship of blast exposure to chronic neurodegenerative diseases noting the paradoxical lowering of Abeta by blast, which along with other observations suggest that blast-related TBI is pathophysiologically distinct from non-blast TBI. Human neuroimaging studies show that blast-related mTBI is associated with a variety of chronic effects that are unlikely to be explained by co-morbid PTSD. We conclude that abundant evidence supports low-level blast as having long-term effects on the nervous system.

  6. Gestational exposure to atrazine has little effect on female reproductive parameters in Sprague-Dawley (SD) rats

    Science.gov (United States)

    Atrazine (ATR), a commonly used herbicide, has been shown to exert reproductive effects in animals; however, most ofthese studies have focused on adult exposure. In contrast, there is limited information available on the reproductive and developmental effects of gestational expos...

  7. Effects of prenatal inhalation exposure to copper nanoparticles on murine dams and offspring

    OpenAIRE

    Adamcakova-Dodd, Andrea; Monick, Martha M.; Powers, Linda S.; Gibson-Corley, Katherine N.; Thorne, Peter S.

    2015-01-01

    Background Increasing numbers of individuals may be exposed to nanomaterials during pregnancy. The overarching goal of this investigation was to determine if prenatal inhalation exposure to copper nanoparticles (Cu NPs) has an effect on dams and offspring, including an analysis of inflammatory markers (Th1/Th2 cytokine profiles). Methods Physicochemical characterization of Cu NPs was performed. Pregnant and non-pregnant mice (C57Bl/6 J) were exposed to Cu NPs or laboratory air in the whole-bo...

  8. Effects of Developmental Exposure to Polychlorinated Biphenyls and/or Polybrominated Diphenyl Ethers on Cochlear Function

    OpenAIRE

    Poon, Emily; Powers, Brian E.; McAlonan, Ruth M.; Ferguson, Duncan C.; Schantz, Susan L

    2011-01-01

    Developmental exposure to polychlorinated biphenyls (PCBs) causes hearing loss that may be due to reduced thyroxine during cochlear development. Polybrominated diphenyl ethers (PBDEs) are structurally similar to PCBs and reduce thyroxine. This study utilized an environmental PCB mixture and a commercial PBDE mixture, DE-71, that represents the PBDEs found in humans to assess the potential for additive effects of PCBs and PBDEs on cochlear function. Female Long-Evans rats were dosed with corn ...

  9. Effects of Antenatal Magnesium Exposure on Intestinal Blood Flow and Outcome in Preterm Neonates

    OpenAIRE

    Gürsoy, Tuğba; İmamoğlu, Ebru Yalın; Ovalı, Fahri; Karatekin, Güner

    2015-01-01

    Objective This study aims to investigate the effects of antenatal magnesium sulfate on intestinal blood flow in preterm neonates. Study Design In this prospective case-match study, 25 preterm neonates exposed to magnesium sulfate antenatally were included (study group). Overall, 25 gestational age-matched neonates who had no exposure to magnesium constituted the control group. Serial daily Doppler flow measurements of superior mesenteric artery (SMA) were performed. The time to reach full fee...

  10. Understanding Engineered Nanomaterial Skin Interactions and the Modulatory Effects of UVR Skin Exposure

    OpenAIRE

    Jatana, Samreen; DeLouise, Lisa A.

    2013-01-01

    The study of engineered nanomaterials for the development of technological applications, nanomedicine, and nano-enabled consumer products is an ever expanding discipline as is the concern over the impact of nanotechnology on human environmental health and safety. In this review we discuss the current state of understanding of nanomaterial skin interactions with a specific emphasis on the effects of ultra-violet radiation (UVR) skin exposure. Skin is the largest organ of the body and is typica...

  11. Effects of PM2 5 exposure on Klebsiella pneumoniae clearance in the lungs of rats

    Institute of Scientific and Technical Information of China (English)

    段争

    2014-01-01

    Objective To investigate the effects of PM2.5 exposure on susceptibility to Klebsiella infection and bacterial clearance,and to discuss its possible mechanisms.Methods Eighty-six healthy male SD rats were randomly divided into 4 groups:a control group,a Klebsiella pneumoniae infection group(infection group),a PM2.5 group and a PM2.5

  12. Sexually Dimorphic Effects of Alcohol Exposure during Development on the Processing of Social Cues

    OpenAIRE

    Kelly, Sandra J.; Leggett, Darnica C.; Cronise, Kim

    2009-01-01

    Aims: The study used an animal model of fetal alcohol spectrum disorders (FASD) to investigate the impact of alcohol exposure during a period equivalent to all three trimesters in humans on social recognition memory. It was hypothesized that the effects on specific aspects of social recognition memory would be sexually dimorphic. Methods: This study exposed rats to ethanol during both the prenatal and early postnatal periods. Two control groups included a group exposed to the administration p...

  13. Effect of exposure to diesel exhaust particles on the susceptibility of the lung to infection.

    OpenAIRE

    Castranova, V; Ma, J. Y.; Yang, H.M.; Antonini, J M; Butterworth, L; Barger, M W; Roberts, J.; Ma, J K

    2001-01-01

    There are at least three mechanisms by which alveolar macrophages play a critical role in protecting the lung from bacterial or viral infections: production of inflammatory cytokines that recruit and activate lung phagocytes, production of antimicrobial reactive oxidant species, and production of interferon (an antiviral agent). In this article we summarize data concerning the effect of exposure to diesel exhaust particles on these alveolar macrophage functions and the role of adsorbed organi...

  14. Occupational Exposure to Aerosolized Brevetoxins during Florida Red Tide Events: Effects on a Healthy Worker Population

    OpenAIRE

    Backer, Lorraine C.; Kirkpatrick, Barbara; Fleming, Lora E.; Cheng, Yung Sung; Pierce, Richard; Bean, Judy A.; Clark, Richard; Johnson, David; Wanner, Adam; Tamer, Robert; Zhou, Yue; Baden, Daniel G.

    2005-01-01

    Karenia brevis (formerly Gymnodinium breve) is a marine dinoflagellate responsible for red tides that form in the Gulf of Mexico. K. brevis produces brevetoxins, the potent toxins that cause neurotoxic shellfish poisoning. There is also limited information describing human health effects from environmental exposures to brevetoxins. Our objective was to examine the impact of inhaling aerosolized brevetoxins during red tide events on self-reported symptoms and pulmonary function. We recruited a...

  15. Detection and drivers of exposure and effects of pharmaceuticals in higher vertebrates

    OpenAIRE

    Shore, Richard F.; Mark A Taggart; Smits, Judit; Mateo, Rafael; Richards, Ngaio L.; Fryday, Steve

    2014-01-01

    Pharmaceuticals are highly bioactive compounds now known to be widespread environmental contaminants. However, research regarding exposure and possible effects in non-target higher vertebrate wildlife remains scarce. The fate and behaviour of most pharmaceuticals entering our environment via numerous pathways remain poorly characterized, and hence our conception and understanding of the risks posed to wild animals is equally constrained. The recent decimation of Asian vulture populations owin...

  16. Effects of inhalation exposure to SRC-II heavy and middle distillates

    Energy Technology Data Exchange (ETDEWEB)

    Springer, D.L.; Miller, R.A.; Weimer, W.C.; Ragan, H.A.; Buschbom, R.L.; Mahlum, D.D.

    1984-11-01

    To expand the data base on potential health effects of coal liquefaction materials, we have performed studies with both solvent refined coal (SRC)-II heavy distillate (HD) and middle distillate (MD). Weight gain for exposed animals was less than that of controls and was dose-related, ranging from no significant difference for animals in the low-exposure group to failure to gain in the high-dose animals. Liver weights increased significantly over controls, and thymus weights decreased for animals sacrificed at 5 and 13 weeks. After both exposure periods, there were significant treatment-related decreases in erythrocyte parameters and in certain types of white blood cells (WBC). Bone marrow cellularity, and numbers of megakaryocytes consistently decreased, suggesting that bone marrow is a target tissue for high-boiling coal liquids. Microscopic evaluation of tissue indicated exposure-related changes is listed. In contrast to the reported mutagenic and carcinogenic effects observed for the high-boiling coal liquids, middle-boiling-range materials lacked such activity in these assays. These data demonstrate a great deal of similarity in the kinds of effects observed following exposure to middle- and high-boiling-range coal liquids. However, the significance of changes in organ weights and peripheral blood parameters are not always readily apparent following a subchronic study. Because of this, we exposed animals to HD in a manner similar to that for the subchronic experiment and have followed these animals throughout their lives for the development of adverse effects such as reduced longevity and the appearance of tumors. Results from this study will be available for mice in FY 1985 and for rats in FY 1986.

  17. The Effect of Repeated Virtual Nicotine Cue Exposure Therapy on the Psychophysiological Responses: A Preliminary Study

    OpenAIRE

    Choi, Jung-Seok; Park, Sumi; Lee, Jun-Young; Jung,Hee-Yeon; Lee, Hae-Woo; Jin, Chong-Hyeon; Kang, Do-Hyung

    2011-01-01

    Objective Smoking related cues may elicit smoking urges and psychophysiological responses in subjects with nicotine dependence. This study aimed to investigate the effect of repeated virtual cue exposure therapy using the surround-screen based projection wall system on the psychophysiological responses in nicotine dependence. Methods The authors developed 3-dimensional neutral and smoking-related environments using virtual reality (VR) technology. Smoking-related environment was a virtual bar...

  18. Alcohol Cue Exposure Effects on Craving and Attentional Bias in Underage College Student Drinkers

    OpenAIRE

    Ramirez, Jason J.; Monti, Peter M.; Colwill, Ruth M.

    2014-01-01

    The effect of alcohol cue exposure on eliciting craving has been well documented and numerous theoretical models assert that craving is a clinically significant construct central to the motivation and maintenance of alcohol-seeking behavior. Furthermore, some theories propose a relationship between craving and attention, such that cue-induced increases in craving bias attention towards alcohol cues, which in turn perpetuates craving. This study examined the extent to which alcohol cues induce...

  19. Introduction: Endocrine disruptors-exposure assessment, novel end points, and low-dose and mixture effects

    OpenAIRE

    Kortenkamp, A

    2007-01-01

    With the aim of discussing new research findings about chemicals able to interfere with the endocrine system, so-called endocrine disruptors, an international workshop was held in Prague, Czech Republic, 10–12 May 2005. The workshop was organized jointly by the EDEN project (Endocrine Disrupters: Exploring Novel Endpoints, Exposure, Low-Dose and Mixture-Effects in Humans, Aquatic Wildlife and Laboratory Animals; http://www.edenresearch.info) and the FIRE project (Risk Assessment of Bromina...

  20. Effects of Dietary Exposure to Zearalenone (ZEN) on Carp (Cyprinus carpio L.)

    OpenAIRE

    Constanze Pietsch; Susanne Kersten; Hana Valenta; Sven Dänicke; Carsten Schulz; Patricia Burkhardt-Holm; Ranka Junge

    2015-01-01

    The mycotoxin zearalenone (ZEN) is frequently contaminating animal feeds including feed used in aquaculture. In the present study, the effects of dietary exposure to ZEN on carp (Cyprinus carpio L.) were investigated. ZEN at three different concentrations (low dose: 332 µg kg−1, medium dose: 621 µg kg−1 and high dose: 797 µg kg−1 final feed, respectively) was administered to juvenile carp for four weeks. Additional groups received the mycotoxin for the same time period but were fed with the u...