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Sample records for 60-hz exposure effects

  1. Effects of exposure to 30 kV/m, 60-Hz electric fields on the social behavior of baboons

    Coelho, A.M. Jr.; Easley, S.P.; Rogers, W.R. (Behavioral Medicine Laboratory, Southwest Foundation for Biomedical Research, San Antonio, TX (USA))

    1991-01-01

    The authors tested the hypothesis that exposure to a 30-kV/m, 60-Hz electric field produces significant change (stress) in the social behavior of adult male baboons (Papio cynocephalus anubis). One group of eight baboons was exposed to an electric field (12 hours per day, 7 days per week for 6 weeks) while a second group of eight baboons was maintained in a sham-exposure (control) condition. Exposed subjects and control subjects were compared over three, six-week experimental periods (pre-exposure, exposure, and post-exposure). Performance rates of six categories of social behaviors (passive affinity, active affinity, approach, tension, threat, and attack) and four categories of nonsocial behaviors (forage, manipulate, posture, and stereotypy) were used to compare the two groups. The results of our study indicate that (1) there were no significant differences between the two groups during the pre-exposure or post-exposure periods; (2) during the exposure period, experimental and control groups exhibited statistically significant differences in the mean performance rates of three behavior categories; (3) within-group comparisons across periods indicate that the experimentally exposed group exhibited statistically significant changes in passive affinity, tension, and stereotypy; and (4) changes in behavior performance among the exposed subjects reflect a stress response to the electric field.

  2. Acute exposure to a 60 Hz magnetic field increases DNA strand breaks in rat brain cells

    Lai, H.; Singh, N.P. [Univ. of Washington, Seattle, WA (United States)

    1997-05-01

    Acute exposure of rats to a 60 Hz magnetic field caused a dose-dependent increase in DNA strand breaks in brain cells of the animals (assayed by a microgel electrophoresis method at 4 h postexposure). An increase in single-strand DNA breaks was observed after exposure to magnetic fields of 0.1, 0.25, and 0.5 mT, whereas an increase in double-strand DNA breaks was observed at 0.25 and 0.5 mT. Because DNA strand breaks may affect cellular functions, lead to carcinogenesis and cell death, and be related to onset of neurodegenerative diseases, the data may have important implications for the possible health effects of exposure to 60 Hz magnetic fields.

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

    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)

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

    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.

  5. Involvement of protein kinase C in the modulation of morphine-induced analgesia and the inhibitory effects of exposure to 60-hz magnetic fields in the land snail, Cepaea nemoralis

    Kavaliers, M.; Ossenkopp, K.P. (Univ. of Western Ontario, London (Canada))

    1990-02-26

    One of the more consistent and dramatic effects of exposure to magnetic fields is the attenuation of morphine-induced analgesia. Results of previous studies have implicated alterations in calcium channel functioning and Ca{sup ++} flux in the mediation of these effects. It is generally accepted that Ca{sup ++}-activated-phospholipid-dependent protein kinase (Protein kinase C; PKC) plays an important role in relaying trans-membrane signaling in diverse Ca{sup ++} dependent cellular processes. In experiment 1 we observed that morphine-induced analgesia in the land snail, Cepaea nemoralis, as measured by the latency of an avoidance behavior to a warmed surface, was reduced by the PKC activator, SC-9, and was enhanced by the PKC inhibitors, H-7 and H-9. In contrast, HA-10004, a potent inhibitor of other protein kinases, but only a very weak inhibitor of PKC, had no effect on morphine-induced analgesia. In experiment 2 exposure of snails for 30 minutes to a 1.0 gauss (rms) 60-Hz magnetic field reduced morphine-induced analgesia. This inhibitory effect of the magnetic field was reduced by the PKC inhibitors, H-7 and H-9, and was augmented by the PKC activator SC-9. These results suggest that: (i) PKC is involved in the modulation of morphine-induced analgesia and, (ii) the inhibitory effects of magnetic fields involve PKC.

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

    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.

  7. Assessment of every day extremely low frequency (Elf) electromagnetic fields (50-60 Hz) exposure: which metrics?

    Because electricity is encountered at every moment of the day, at home with household appliances, or in every type of transportation, people are most of the time exposed to extremely low frequency (E.L.F.) electromagnetic fields (50-60 Hz) in a various way. Due to a lack of knowledge about the biological mechanisms of 50 Hz magnetic fields, studies seeking to identify health effects of exposure use central tendency metrics. The objective of our study is to provide better information about these exposure measurements from three categories of metrics. We calculated metrics of exposure measurements from data series (79 very day exposed subjects), made up approximately 20,000 recordings of magnetic fields, measured every 30 seconds for 7 days with an E.M.D.E.X. II dosimeter. These indicators were divided into three categories : central tendency metrics, dispersion metrics and variability metrics.We use Principal Component Analysis, a multidimensional technique to examine the relations between different exposure metrics for a group of subjects. Principal component Analysis (P.C.A.) enabled us to identify from the foreground 71.7% of the variance. The first component (42.7%) was characterized by central tendency; the second (29.0%) was composed of dispersion characteristics. The third component (17.2%) was composed of variability characteristics. This study confirm the need to improve exposure measurements by using at least two dimensions intensity and dispersion. (authors)

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

    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.

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

    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.

  10. 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

    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.)

  11. Long-term exposure to a magnetic field (5 mT at 60 Hz) increases X-ray-induced mutations

    Exposure to extremely low frequency magnetic field (ELFMF) at 400 mT has been shown to induce mutations (Mutat. Res., 349: 109-114, 1996; Int. J. Radiat. Biol., 71: 75-79, 1997; and Biochem. Biophys. Res. Commun., 243: 579-584, 1998). However, whether ELFMF at low flux densities (under 1 mT) induces mutations is debatable. We investigated the effect of long-term exposure to 5 mT ELFMF at 60 Hz on mutant frequency. Chinese hamster ovary K1 (CHO-K1) cells were exposed or sham-exposed to 5 mT ELFMF for up to 6 weeks with or without X-irradiation (3 Gy), and the mutant frequency of the hypoxanthine-guanine phosphoribosyl transferase (HPRT) gene was analyzed. Long-term exposure to 5 mT ELFMF did not increase mutations, suggesting a threshold for mutation induction greater than 115 mA/m2 or a magnetic density of 5 mT. However, enhancement of the X-ray-induced mutation rate was observed after treatment with X-irradiation followed by long-term exposure to 5 mT ELFMF. At little as a 1-week exposure to ELFMF after X-irradiation enhanced the mutation rate. We also found that 400 mT exposure enhanced the mutation rate induced by X-irradiation (Mutat. Res., 349: 109-114, 1996). These results suggest that exposure to more than 5 mT ELFMF may promote X-ray-induced mutations. (author)

  12. 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

    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

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

    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...

  14. 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

    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.

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

    Davies, M S

    1996-01-01

    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(2+) (B(H) = 78.3 mu T, B(HAC) = 40 mu T peak-peak at 60 Hz, B(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. PMID:8860733

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

    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.

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

    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)

  18. Residential 60-Hz magnetic fields and temporal variability

    Banks, Robert Stephen

    1998-06-01

    The basic question addressed by this research is: How well can data from a single measurement visit estimate longer-term ambient residential 60-Hz magnetic field levels? We undertook repeat 60-Hz magnetic field measurements every two months for one year, plus one additional visit for 14 days of measurement. The study sample consisted of 51 single-family homes, 24 in Minneapolis-St. Paul and 27 in Detroit. Homes were selected by random-digit dialing; each was home to a child eligible to serve a control subject in the National Cancer Institute-Children's Cancer Group Electromagnetic Fields and Radon Study. Trained survey interviewers obtained all measurement data, using an expanded measurement protocol from the main study: (1) spot 60-Hz magnetic field measurements at the centers of three rooms and at the front door; (2) 24- hour (or 14 day) 60-Hz magnetic field measurement in the subject child's bedroom; and (3) geomagnetic field at the centers of two rooms and on the child's bed. The data set available for analysis consists of 349 out of 357 (97.8%) possible sets of spot measurements and 1060 out of 1071 (99.0%) possible days of 24-hour and two-week measurements. A Long-Term Estimate, Child's Bedroom, or LTECB, the geometric mean of the 24-hour measurement geometric means, was used as the reference for analysis. The LTECB was analyzed for house-level main effects and for repeated-measures (temporal) main effects. House-level main effects account for only 41% of the variability in the LTECB. The statistically significant main effects are study area, wire code and population density. A clear trend of increasing LTECB with population density is evident. The seasonal effect is small, but statistically significant. There is no evidence for a day-of-week effect, but a statistically significant diurnal effect is present. Correlation coefficients relating the LTECB to any of three primary single-visit measurement and exposure metric surrogates are >.9. However, when

  19. 60 HZ beam motion reduction at NSLS UV storage ring

    A significant reduction in 60 hz beam motion has been achieved in the UV storage ring. From the wide band harmonic beam motion signal, 60 hz signal is extracted by tuned bandpass filter. This signal is processed by the phase and amplitude adjustment circuits and then, it is fed into the harmonic orbit generation circuits. Several harmonics, near the tune, were canceled by employing one circuit for each harmonic. The design and description of this experiment is given in this paper. The results showing reduction in beam motion at 60 hz are also provided

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

    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

  1. 50-60 Hz frequency electric and magnetic fields; Champs electriques et magnetiques de frequence 50-60 Hz

    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.)

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

    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)

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

    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

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

    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.

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

    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)

  6. In vitro assessment of the immunity of implantable cardioverter-defibrillators to magnetic fields of 50/60 Hz

    Public concern for the compatibility of electromagnetic (EM) sources with active implantable medical devices (AIMD) has prompted the development of new systems that can perform accurate exposure studies. EM field interference with active cardiac implants (e.g. implantable cardioverter-defibrillators (ICDs)) can be critical. This paper describes a magnetic field (MF) exposure system and the method developed for testing the immunity of ICD to continuous-wave MFs. The MFs were created by Helmholtz coils, housed in a Faraday cage. The coils were able to produce highly uniform MFs up to 4000 µT at 50 Hz and 3900 µT at 60 Hz, within the test space. Four ICDs were tested. No dysfunctions were found in the generated MFs. These results confirm that the tested ICDs were immune to low frequency MFs. (paper)

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

    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.)

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

    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.

  9. A new look at gamma? High- (>60 Hz) γ-band activity in cortical networks: function, mechanisms and impairment.

    Uhlhaas, Peter J; Pipa, Gordon; Neuenschwander, Sergio; Wibral, Michael; Singer, Wolf

    2011-03-01

    γ-band oscillations are thought to play a crucial role in information processing in cortical networks. In addition to oscillatory activity between 30 and 60 Hz, current evidence from electro- and magnetoencephalography (EEG/MEG) and local-field potentials (LFPs) has consistently shown oscillations >60 Hz (high γ-band) whose function and generating mechanisms are unclear. In the present paper, we summarize data that highlights the importance of high γ-band activity for cortical computations through establishing correlations between the modulation of oscillations in the 60-200 Hz frequency and specific cognitive functions. Moreover, we will suggest that high γ-band activity is impaired in neuropsychiatric disorders, such as schizophrenia and epilepsy. In the final part of the paper, we will review physiological mechanisms underlying the generation of high γ-band oscillations and discuss the functional implications of low vs. high γ-band activity patterns in cortical networks. PMID:21034768

  10. 50-60 Hz magnetic fields and health: what's new?

    In December 2013, the SCENIHR (Scientific Committee on Emerging and Newly Identified Health Risks) released a new report on the health risks associated with electromagnetic fields from 0 to 300 GHz. This literature review does not show a possible health risk associated with the extremely low frequency magnetic field exposure. Concerning childhood leukemia, the report raises a number of critical issues that deserve more detailed analysis. Consideration of the exposure remains the Achilles' heel of epidemiological studies and none of these studies has provided a suitable answer to this question. The issue of childhood leukemia is analyzed here in the light of the recent literature. Given the weaknesses and gaps in exposure assessment, the heterogeneity of the studies and the reduction of the odds ratio over time for the most vulnerable populations, consistency between study results is not obvious. After 30 years of research, two key points deserve attention: the overall exposure assessment, taking into account all sources of exposure, on the one hand; and the duration of exposure (and not only the average over 24 hours) including the total duration of residence of the mother and child, on the other hand. (authors)

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

    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.

  12. The question of health effects from exposure to electromagnetic fields

    The question of health effects related to exposures from non-ionizing and non-optical electromagnetic fields is currently concentrated in two frequency ranges: extremely low frequency (ELF) electric and magnetic fields, mainly at the overhead high-voltage power line frequencies of 50/60 Hz, and radiofrequency (RF) radiation, encompassing the frequency range from a few kilohertz to 300 GHz. The part between 300 MHz and 300 GHz is also usually named microwaves (MW); from this point of view, microwaves are part of the whole RF spectrum. The following brief overview is aimed at evaluating the state of knowledge regarding the question of health effects associated to exposures to ELF and RF/MW fields

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

    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.

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

    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

  15. Power line emission 50/60 Hz and Schumann resonances observed by microsatellite Chibis-M in the Earth's ionosphere

    Dudkin, Denys; Pilipenko, Vyacheslav; Dudkin, Fedir; Pronenko, Vira; Klimov, Stanislav

    2015-04-01

    The overhead power lines are the sources of intense wideband electromagnetic (EM) emission, especially in ELF-VLF range, because of significant length (up to a few thousand kilometers) and strong 50/60 Hz currents with noticeable distortion. The radiation efficiency of the power line emission (PLE) increases with the harmonic order, so they are well observed by ground-based EM sensors. However their observations by low orbiting satellites (LEO) are very rare, particularly at basic harmonic 50/60 Hz, because of the ionospheric plasma opacity in ELF band. The Schumann resonance (SR) is the narrow-band EM noise that occurs due to the global thunderstorm activity in the Earth-ionosphere cavity. The first five eigenmodes of the SR are 7.8, 14.3, 20.8, 27.3 and 33.8 Hz and, thus, SR harmonics are also strongly absorbed by the Earth ionosphere. The published numerical simulations show that the penetration depth of such an ELF emission into the Earth's ionosphere is limited to 50-70 km for electric field and 120-240 km for magnetic field. From this follows, that PLE and SR can hardly ever be detected by LEO satellites, i.e. above the F-layer of ionosphere. In spite of this fact, these emissions were recently observed with use of the electric field antennas placed on the satellites C/NOFS (USA) and Chibis-M (Russia). Microsatellite Chibis-M was launched on January 24, 2012, at 23:18:30 UTC from the cargo ship "Progress M-13M" to circular orbit with altitude ~500 km and inclination ~52° . Chibis-M mass is about 40 kg where one third is a scientific instrumentation. The dimensions of the microsatellite case are 0.26x0.26x0.54 m with the outside mounted solar panels, service and scientific instrumentation. The main scientific objective of Chibis-M is the theoretical model verification for the atmospheric gamma-ray bursts. It requires the study of the accompanying EM processes such as the plasma waves produced by the lightning discharges in the VLF band. Chibis-M decayed on 15

  16. 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

    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....

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

    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.

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

    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).

  19. Electric field of the power terrestrial sources observed by microsatellite Chibis-M in the Earth's ionosphere in frequency range 1-60 Hz

    Dudkin, Fedir; Korepanov, Valery; Dudkin, Denis; Pilipenko, Vyacheslav; Pronenko, Vira; Klimov, Stanislav

    2015-07-01

    The power line emission (PLE) 50/60 Hz and the Schumann resonance (SR) harmonics were detected by the use of a compact electrical field sensor of length 0.42 m during microsatellite Chibis-M mission in years 2012-2014. The initial orbit of Chibis-M has altitude 500 km and inclination 52°. We present the space distribution of PLE and its connections with the possible overhead power lines. PLE has been recorded both in the shade and sunlit parts of the orbits as opposed to SR which have been recorded only in the nightside of the Earth. The cases of an extra long distance of PLE propagation in the Earth's ionosphere and increased value of SR Q factor have been also observed. These results should stimulate the ionosphere model refinement for ultralow frequency and extremely low frequency electromagnetic wave propagation as well as a study on new possibility of the ionosphere diagnostics.

  20. Residential exposures to indoor air pollutants could yield childhood leukemia risk levels similar to those associated with 60 Hz magnetic fields

    Over a decade ago Easterly suggested that electromagnetic fields may be able to participate in a cooperative process leading to the expression of cancer. Evidence derived from the literature is presented to support the suggestion that potentially cooperative factors other than electromagnetic fields are present in homes in sufficient quantities to result in approximately the same risk levels as are being measured in epidemiology studies of childhood leukemia and electromagnetic fields. Generally these odds ratios vary from 1.5 to 2.5

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

    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.

  2. Heat exposure effects among firefighters

    Patel Harshad; Rao Nellore; Saha Asim

    2006-01-01

    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 prevale...

  3. Heat exposure effects among firefighters

    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

  4. 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

    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.

  5. Epigenetic Effects of Cannabis Exposure.

    Szutorisz, Henrietta; Hurd, Yasmin L

    2016-04-01

    The past decade has witnessed a number of societal and political changes that have raised critical questions about the long-term impact of marijuana (Cannabis sativa) that are especially important given the prevalence of its abuse and that potential long-term effects still largely lack scientific data. Disturbances of the epigenome have generally been hypothesized as the molecular machinery underlying the persistent, often tissue-specific transcriptional and behavioral effects of cannabinoids that have been observed within one's lifetime and even into the subsequent generation. Here, we provide an overview of the current published scientific literature that has examined epigenetic effects of cannabinoids. Though mechanistic insights about the epigenome remain sparse, accumulating data in humans and animal models have begun to reveal aberrant epigenetic modifications in brain and the periphery linked to cannabis exposure. Expansion of such knowledge and causal molecular relationships could help provide novel targets for future therapeutic interventions. PMID:26546076

  6. Chernobyl accident. Exposures and effects

    from the disintegration of the former Soviet Union. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has given particular attention to the accident. Estimates of average doses in separate regions of countries and for the population of the northern hemisphere as a whole were presented in Annex D of the UNSCEAR 1988 Report. The experience gained in treating the immediate radiation injuries of workers and fire fighters involved in controlling the accident were also reviewed in the UNSCEAR 1988 Report (Annex G). The UNSCEAR Committee is currently involved in the final phase of preparation of a further assessment of the exposures and effects of the accident. During the last several years, considerable attention has been devoted to investigating possible associations between health effects in the populations and the exposure to radionuclides released and dispersed following the Chernobyl accident. Of particular note has been the occurrence of numerous thyroid cancers in children. The number of thyroid cancers in individuals exposed in childhood, particularly in the severely contaminated areas of Belarus, Russia, and Ukraine is considerably greater than expected based on previous knowledge. The high incidence and the short induction period have not been experienced in other populations, and other factors are most certainly influencing the risk. If the current trend continues, further thyroid cancers can be expected to occur, especially in those exposed at young ages. The most recent findings indicate that the thyroid cancer risk for those older than 10 years of age at the time of the accident is leveling off, while the increase continues for those younger than 4-5 years in 1986. Apart from the dramatic increase in thyroid cancer after childhood exposure, there is no evidence of a major public health impact 14 years after the Chernobyl accident. No increases in overall cancer incidence or mortality have been observed that could be attributed

  7. Medical exposure and the effects of radiation

    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)

  8. Neurobehavioral and neurodevelopmental effects of pesticide exposures

    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 ...

  9. Skin Exposures & Effects in the Workplace

    ... 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 ...

  10. Medical exposure and effective dose

    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.)

  11. EFFECTS OF TRITIUM GAS EXPOSURE ON POLYMERS

    Clark, E.; Fox, E.; Kane, M.; Staack, G.

    2011-01-07

    Effects of tritium gas exposure on various polymers have been studied over the last several years. Despite the deleterious effects of beta exposure on many material properties, structural polymers continued to be used in tritium systems. Improved understanding of the tritium effects will allow more resistant materials to be selected. Currently polymers find use mainly in tritium gas sealing applications (eg. valve stem tips, O-rings). Future uses being evaluated including polymeric based cracking of tritiated water, and polymer-based sensors of tritium.

  12. Methylmercury Exposure and Health Effects

    Hong, Young-Seoub; Kim, Yu-Mi; Lee, Kyung-Eun

    2012-01-01

    Methylmercury is a hazardous substance that is of interest with regard to environmental health, as inorganic mercury circulating in the general environment is dissolved into freshwater and seawater, condensed through the food chain, ingested by humans, and consequently affects human health. Recently, there has been much interest and discussion regarding the toxicity of methylmercury, the correlation with fish and shellfish intake, and methods of long-term management of the human health effect...

  13. Effects of prenatal exposure to marijuana.

    Kozer E; Koren G

    2001-01-01

    QUESTION: I am treating a 27-year-old woman who is now in her 10th week of pregnancy. She smokes marijuana two to three times a week, but does not use other drugs. She also smokes 20 cigarettes a day. I am concerned about the effects of marijuana exposure on her baby. ANSWER: It is not always possible to isolate the effect of marijuana exposure from other possible confounders on pregnancy outcome. Although marijuana is not an established human teratogen, recent well conducted studies suggest ...

  14. Health effects of biomass exposure

    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

  15. Biological effects and hazards of radiation exposure

    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

  16. Radiation effects after exposure during prenetal development

    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.)

  17. Experimental effects of exposure to pornography

    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...

  18. Microwave radiation - Biological effects and exposure standards

    Lindsay, I.R.

    1980-06-01

    The thermal and nonthermal effects of exposure to microwave radiation are discussed and current standards for microwave exposure are examined in light of the proposed use of microwave power transmission from solar power satellites. Effects considered include cataractogenesis at levels above 100 mW/sq cm, and possible reversible disturbances such as headaches, sleeplessness, irritability, fatigue, memory loss, cardiovascular changes and circadian rhythm disturbances at levels less than 10 mW/sq cm. It is pointed out that while the United States and western Europe have adopted exposure standards of 10 mW/sq cm, those adopted in other countries are up to three orders of magnitude more restrictive, as they are based on different principles applied in determining safe limits. Various aspects of the biological effects of microwave transmissions from space are considered in the areas of the protection of personnel working in the vicinity of the rectenna, interactions of the transmitted radiation with cardiac pacemakers, and effects on birds. It is concluded that thresholds for biological effects from short-term microwave radiation are well above the maximal power density of 1 mW/sq cm projected at or beyond the area of exclusion of a rectenna.

  19. HELLE: Health Effects of Low Level Exposures

    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

  20. Effective radiation exposure in digital volume tomography

    Measurements of the effective doses and the organ doses using head phantoms are supposed to study the effects of different resolutions, volumes and field of view positions on the patient's radiation exposure during digital volume tomography. The details of the measuring instruments and the different volume tomography devices from KaVo are described. All the resulting dose values are related to the specific phantom and were calculated using the average values from ICRP, i.e. these values can be used as reference but cannot be transferred to patients. Therefore significant differences can be seen in comparison with other studies.

  1. Microwave radiation: biological effects and exposure standards

    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.

  2. Statistical Methods for the Evaluation of Health Effects of Prenatal Mercury Exposure

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

    2002-01-01

    Environmental epidemiology; Structural equation; Exposure measurement error; multiple endpoints; effect of prenatal mercury exposure; Exposure standards; Benchmark dose......Environmental epidemiology; Structural equation; Exposure measurement error; multiple endpoints; effect of prenatal mercury exposure; Exposure standards; Benchmark dose...

  3. Health effects of industrial exposure to thorium

    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

  4. Biomolecular Effects of Cold Plasma Exposure

    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.

  5. Noise Exposure of School Teachers – Exposure Levels and Health Effects

    Hadzi-Nikolova, Marija; Mirakovski, Dejan; Zdravkovska, Milka; Angelovska, Bistra; Doneva, Nikolinka

    2013-01-01

    Faculty of Natural and Technical Sciences and Faculty of Medical Sciences starting from December 2012, launched joint study in order to investigate personal noise exposure and associated health effects in general school teachers population, starting from kindergartens up to high schools in Stip, Macedonia. In order to determine workplace associated noise exposure and associated health effects in this specific profession, a full shift noise exposure of 40 teachers from 1 kindergart...

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

    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

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

    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...

  8. Epistemological limitation for attributing health effects to natural radiation exposure

    The attribution of health effects to prolonged radiation exposure situations, such as those experienced in nature, is a challenging problem. The paper describes the epistemological limitations for such attribution it demonstrate that in most natural exposure situations, the theory of radiation-related sciences is not capable to provide the scientific evidence that health effects actually occur (or do not occur) and, therefore, that radiation effects are attributable to natural exposure situations and imputable to nature. Radiation exposure at high levels is known to provoke health effects as tissue reactions. If individuals experience these effects they can be attributed to the specific exposure with a high degree of confidence under the following conditions: the dose incurred have been higher that the relevant dose-threshold for the specific effect; and an unequivocal pathological diagnosis is attainable ensuring that possible competing causes have been eliminated. Only under these conditions, the occurrence of the effect may be properly attested and attributed to the exposure. However, even high levels of natural radiation exposure are lower than relevant dose-thresholds for tissue reactions and, therefore, natural radiation exposure is generally unable to cause these type of effects. One exception to this general rule could be situations of high levels of natural radiation exposure that might be sufficient to induce opacities in the lens of the eyes (which could be considered a tissue-reaction type of effect)

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

    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.

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

    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.

  11. Ambient radiation exposure: measurements and effects

    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

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

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

    2004-01-01

    , 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......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...... approach is one of the most widely used methods for development of exposure limits. An important advantage of this approach is that it can be applied to observational data. However, in this type of data, exposure markers are seldom measured without error. It is shown that, if the exposure error is ignored...

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

    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. PMID:17479582

  14. Effects of Prenatal Exposure to Phthalates

    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.…

  15. Effect of mild diarrhea on tacrolimus exposure

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

    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...

  17. US Oil Price Exposure: The Industry Effects

    Don Bredin; John Elder

    2011-01-01

    This paper investigates the exposure of industry level portfolios to oil price shocks. Our paper utilizes the Campbell (1991) decomposition of stock returns based on a log-linear approximation to the discounted present value relation while allowing for time varying expected returns. The results from our baseline regressions indicate that there is little sensitivity in industry level portfolios to unexpected movements in oil prices, with the gold, oil & gas and retail industries being the only...

  18. The Effects of Mere Exposure to Political Advertisements.

    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…

  19. Methylmercury exposure and adverse cardiovascular effects in Faroese whalingmen

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

    2009-01-01

    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...... and outcomes in groups to derive latent exposure and response variables in SEMs. We used multiple regression analysis to compare the predictive validity of individual exposure biomarkers and the latent exposure variable on individual and latent outcomes. RESULTS: The toenail mercury concentrations...

  20. Effects of high vs low-level radiation exposure

    In order to appreciate adequately the various possible effects of radiation, particularly from high-level vs low-level radiation exposure (HLRE, vs LLRE), it is necessary to understand the substantial differences between (a) exposure as used in exposure-incidence curves, which are always initially linear and without threshold, and (b) dose as used in dose-response curves, which always have a threshold, above which the function is curvilinear with increasing slope. The differences are discussed first in terms of generally familiar nonradiation situations involving dose vs exposure, and then specifically in terms of exposure to radiation, vs a dose of radiation. Examples are given of relevant biomedical findings illustrating that, while dose can be used with HLRE, it is inappropriate and misleading the LLRE where exposure is the conceptually correct measure of the amount of radiation involved

  1. Combined Toxic Exposures and Human Health: Biomarkers of Exposure and Effect

    Johan Högberg

    2011-02-01

    Full Text Available Procedures for risk assessment of chemical mixtures, combined and cumulative exposures are under development, but the scientific database needs considerable expansion. In particular, there is a lack of knowledge on how to monitor effects of complex exposures, and there are few reviews on biomonitoring complex exposures. In this review we summarize articles in which biomonitoring techniques have been developed and used. Most examples describe techniques for biomonitoring effects which may detect early changes induced by many chemical stressors and which have the potential to accelerate data gathering. Some emphasis is put on endocrine disrupters acting via epigenetic mechanisms and on carcinogens. Solid evidence shows that these groups of chemicals can interact and even produce synergistic effects. They may act during sensitive time windows and biomonitoring their effects in epidemiological studies is a challenging task.

  2. Health effects of occupational exposures to vehicle emissions in Shanghai.

    Zhou, W; Yuan, D; Ye, S; Qi, P; Fu, C; Christiani, D C

    2001-01-01

    The authors investigated the health effects of occupational exposures to vehicle emissions in 745 bus drivers, conductors, and taxi drivers, compared with 532 unexposed controls, in Shanghai. Logistic regression and general linear models were used to examine the relationship between exposure and respiratory illness. Results showed that the prevalences of some respiratory symptoms and chronic respiratory diseases were significantly higher (p pain, phlegm, chronic rhinitis, and chronic pharyngitis were 1.95 (95% CI 1.55-2.46), 3.90 (95% CI 2.61-5.81), 1.96 (95% CI 1.11-3.46), and 4.19 (95% CI 2.49-7.06), respectively. Also, there were exposure time response relationships for the prevalences of phlegm and chronic respiratory disease. Pulmonary function and blood lead levels were not significantly correlated with exposure status. The results suggest that occupational exposure to vehicle emissions may induce detectable adverse health effects. PMID:11210009

  3. Mercury Quick Facts: Health Effects of Mercury Exposure

    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 ...

  4. Linking exposure to environmental pollutants with biological effects

    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...... setting, 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...

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

    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.

  6. Human Health Effects Associated with Exposure to Toxic Cyanobacteria

    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...

  7. Exposure and Health Effects of Fungi on Humans.

    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

  8. Time effect of stimulus exposure in semantic verification task

    Injac Božana

    2006-01-01

    Full Text Available The effect of stimulus exposure in semantic verification task within the framework of two levels of complexity of experimental context was examined in nine experiments. The complexity of experimental context was defined in terms of number of constitutive elements of a statement (subject, predicate and copula which vary in the course of an experiment. Four experiments with different exposure duration have been performed within the framework of minimal complexity (where only one element of statement varies, while five experiments with different exposure duration have been conducted within the framework of medium complexity (where two elements of statement vary. Systematic manipulation of the two variables (i.e. complexity and exposure duration provides variation of processing load in verification process, thus influencing the efficiency of working memory during the verification task. The obtained results indicate that the cognitive load variation (defined in terms of variation of exposure duration affects processing of subject-predicate congruency, which is an obligatory step in statement verification. The shorter the exposure duration, the bigger the difference in processing latencies between “congruent” and “incongruent” statements. The effects are more pronounced for statements presented in the framework of medium complexity. Also, the reduction of exposure duration affects the error rate as well as processing of statement’s quality (i.e. affirmative vs. negative form of a statement.

  9. Effect of Prenatal Exposure to Kitchen Fuel on Birth Weight

    Yugantara Ramesh Kadam; Anugya Mimansa; Pragati Vishnu Chavan; Alka Dilip Gore

    2013-01-01

    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), D...

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

    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. Tobacco Smoke Exposure during Childhood: Effect on Cochlear Physiology

    Cristiane Lopes; Marcella Gameiro; Beatriz Massa; Nicolly Gudayol; Alessandra S. Durante; Beatriz Pucci

    2013-01-01

    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 ...

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

    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...

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

    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

  14. Effectiveness of post-exposure rabies prophylaxis

    Firooz Esmaeilzadeh

    2014-12-01

    Conclusion: The implementation of PEP for animal bitten people remarkably reduced the burden of disease in community. Calculations with primitive cost estimations im-plicitly revealed that this intervention is a most cost-effectiveness program.

  15. Contaminant Exposure and Effects--Terrestrial Vertebrates

    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...

  16. Effects upon health of occupational exposure to microwave radiation (radar)

    The effects of occupational experience with microwave radiation (radar) on the health of US enlisted Naval personnel were studied in cohorts of approximately 20,000 men with maximum opportunity for exposure (electronic equipment repair) and 20,000 with minimum potential for exposure (equipment operation) who served during the Korean War period. Potential exposure was assessed in terms of occupational duties, length of time in occupation and power of equipment at the time of exposure. Actual exposure to members of each cohort could not be established. Mortality by cause of death, hospitalization during military service, later hospitalization in Veterans Administration (VA) facilities, and VA disability compensation were the health indexes studied, largely through the use of automated record systems. No adverse effects were detected in these indexes that could be attributed to potential microwave radiation exposures during the period 1950-1954. Functional and behavioral changes and ill-defined conditions, such as have been reported as microwave effects, could not be investigated in this study but subgroups of the living study population can be identified for expanded follow-up

  17. Effects of ultraviolet exposure on the immune system.

    Garssen, J; van Loveren, H

    2001-01-01

    Depletion of stratospheric ozone and changes in lifestyle lead to an increased exposure to ultraviolet (UV) wavebands, especially in the UVB region (280-320 nm). Besides the beneficial effects of UV exposure, such as vitamin D production, cosmetic tanning, and adaptation to solar UV, UV exposure can also have adverse consequences on human health, notably sunburn, skin cancer, and ocular damage. Over the last two and a half decades it has become evident that especially UVB exposure and to a lesser extent UVA modulates specific as well as nonspecific immune responses. Several reports have shown that this immunomodulation plays at least a partial role in the induction of skin cancer. In addition, UVB exposure has been demonstrated to impair resistance to some infections. On the other hand, immunomodulation resulting from UVB exposure might be physiologically important in inhibiting responses to neoantigens in the skin induced by UV exposure. In the last 20 years UV has been used frequently as an experimental tool to unravel immune responses-especially immune responses initiated in the skin (i.e., photoimmunology). In this review, the major mechanisms responsible for UV-induced immunomodulation and its consequences are summarized. PMID:11922079

  18. Frequency and collective effective dose equivalent of medical exposures

    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)

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

    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. Cardiovascular effects of environmental noise exposure

    Münzel, Thomas; Gori, Tommaso; Babisch, Wolfgang; Basner, Mathias

    2014-01-01

    The role of noise as an environmental pollutant and its impact on health are being increasingly recognized. Beyond its effects on the auditory system, noise causes annoyance and disturbs sleep, and it impairs cognitive performance. Furthermore, evidence from epidemiologic studies demonstrates that environmental noise is associated with an increased incidence of arterial hypertension, myocardial infarction, and stroke. Both observational and experimental studies indicate that in particular nig...

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

    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. Health effects of airborne exposures from concentrated animal feeding operations

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

    2006-01-01

    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...... effects related to low-level gas and particulate emissions. Most information comes from studies among workers in CAFO installations. Research over the last decades has shown that microbial exposures, especially endotoxin exposure, are related to deleterious respiratory health effects, of which cross...... 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 but...

  3. Childhood sensorineural hearing loss: effects of combined exposure with aging or noise exposure later in life.

    Aarhus, Lisa; Tambs, Kristian; Nafstad, Per; Bjørgan, Eskil; Engdahl, Bo

    2016-05-01

    The aim of the study was to examine childhood high-frequency sensorineural hearing loss (HF-SNHL) and the effects of combined exposure with aging or noise exposure on HF hearing thresholds in adulthood. Population-based cohort study of 30,003 adults (mean age 40 years) underwent an audiometry and completed a hearing questionnaire. At age 7-13 years, the same people had participated in a longitudinal school hearing investigation, in which 283 participants were diagnosed with HF-SNHL [PTA 3-8 kHz ≥ 25 dB HL (mean 45 dB HL), worse hearing ear], and 29,720 participants had normal hearing thresholds. The effect of childhood HF-SNHL on adult hearing threshold was significantly moderated by age. Age stratified analyses showed that the difference in HF hearing thresholds between adults with and without childhood HF-SNHL was 33 dB (95 % CI 31-34) in young adults (n = 173, aged 20-39 years) and 37 dB (95 % CI 34-39) in middle-aged adults (n = 110, aged 40-56 years). The combined exposure of childhood HF-SNHL and noise exposure showed a simple additive effect. It appears to be a super-additive effect of childhood-onset HF-SNHL and aging on adult hearing thresholds. An explanation might be that already damaged hair cells are more susceptible to age-related degeneration. To exclude possible birth cohort effects, the finding should be confirmed by a study with several audiometries in adulthood. PMID:25975623

  4. Neuroprotective effect of wormwood against lead exposure

    Kharoubi O

    2011-01-01

    Full Text Available Background : Lead poisoning is a potential factor in brain damage, neurochemical dysfunction and severe behavioral problems. Considering this effect, our study was carried out to investigate the effects of wormwood to restore enzymes activities, lipid peroxidation and behavioral changes induced by lead. Methods : Thirty Wistar rats were divided into five groups (n = 6 in each group: three groups exposed to 750 ppm of lead acetate in the drinking water for 11 weeks and two groups as control. Aqueous wormwood extract (200 mg/kg body weight was administrated to intoxicated (Pb(-+A.AB and control groups (A.AB for four supplemental weeks. Activities of acetylcholinesterase (AchE, monoamine oxidase (MAO and thiobarbituric acid-reactive substances (TBARS level were determined in the hypothalamus, hippocampus, cortex and striatum of male rats and the grooming and locomotors activity were defined in all groups. Results: The intoxicated group (Pb has a significantly increased TBARS value compared with the control in all brain regions (P < 0.05 and, after treatment with the wormwood extract, a significant reduction was noted. The enzyme activity decreased significantly (P < 0.05 in the Pb group compared with the control, essentially for the hippocampus (AchE: -57%, MAO: -41% and the striatum (AchE: -43%, MAO: -51%. After wormwood extract administration, the AchE and MAO activity were significantly increased in all brain regions compared with the Pb group (P < 0.05. The behavioral test (locomotors and grooming test indicates a significant hyperactivity in the Pb group compared with the control group. After treatment with wormwood extract, the Pb(-+A.Ab indicates a lower activity compared with Pb. Conclusion : These data suggest that wormwood extract may play a very useful role in reduction of the neurotoxicological damage induced by lead.

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

    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

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

    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)

  7. Effects of embryonic cyclosporine exposures on brain development and behavior.

    Clift, Danielle E; Thorn, Robert J; Passarelli, Emily A; Kapoor, Mrinal; LoPiccolo, Mary K; Richendrfer, Holly A; Colwill, Ruth M; Creton, Robbert

    2015-04-01

    Cyclosporine, a calcineurin inhibitor, is successfully used as an immunosuppressant in transplant medicine. However, the use of this pharmaceutical during pregnancy is concerning since calcineurin is thought to play a role in neural development. The risk for human brain development is difficult to evaluate because of a lack of basic information on the sensitive developmental times and the potentially pleiotropic effects on brain development and behavior. In the present study, we use zebrafish as a model system to examine the effects of embryonic cyclosporine exposures. Early embryonic exposures reduced the size of the eyes and brain. Late embryonic exposures did not affect the size of the eyes or brain, but did lead to substantial behavioral defects at the larval stages. The cyclosporine-exposed larvae displayed a reduced avoidance response to visual stimuli, low swim speeds, increased resting, an increase in thigmotaxis, and changes in the average distance between larvae. Similar results were obtained with the calcineurin inhibitor FK506, suggesting that most, but not all, effects on brain development and behavior are mediated by calcineurin inhibition. Overall, the results show that cyclosporine can induce either structural or functional brain defects, depending on the exposure window. The observed functional brain defects highlight the importance of quantitative behavioral assays when evaluating the risk of developmental exposures. PMID:25591474

  8. Biological effects of low-dose ionizing radiation exposure

    The report on the meeting of the Strahlenschutzkommission 2007 concerning biological effects of low-dose ionizing radiation exposure includes the following contributions: Adaptive response. The importance of DNA damage mechanisms for the biological efficiency of low-energy photons. Radiation effects in mammography: the relative biological radiation effects of low-energy photons. Radiation-induced cataracts. Carcinomas following prenatal radiation exposure. Intercellular apoptosis induction and low-dose irradiation: possible consequences for the oncogenesis control. Mechanistic models for the carcinogenesis with radiation-induced cell inactivation: application to all solid tumors in the Japanese atomic bomb survivors. Microarrays at low radiation doses. Mouse models for the analysis of biological effects of low-dose ionizing radiation. The bystander effect: observations, mechanisms and implications. Lung carcinoma risk of Majak workers - modeling of carcinogenesis and the bystander effect. Microbeam studies in radiation biology - an overview. Carcinogenesis models with radiation-induced genomic instability. Application to two epidemiological cohorts.

  9. Biological effects from electromagnetic fields: Research progress and exposure measurements

    Although it is commonly accepted that exposure to high levels of electromagnetic, micro- and radiofrequency waves produces harmful effects to the health of man, the formulation of exposure limits is still an open process and dependent upon the evolving level of knowledge in this field. This paper surveys the current level of knowledge gained through 'in vitro' and 'in vivo' radiological and epidemiological studies on different types of electromagnetic radiation derived effects - chromosomal, mutagenic, carcinogenic. It then reviews efforts by international organizations, e. g., the International Radiation Protection Association, to establish exposure limits for radiofrequency electromagnetic fields. Brief notes are given on the electromagnetic radiation monitoring campaign being performed by public health authorities in the Lazio Region of Italy

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

    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)

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

    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

  12. Effective biological dose from occupational exposure during nanoparticle synthesis

    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.

  13. Effective biological dose from occupational exposure during nanoparticle synthesis

    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.

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

    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

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

    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)

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

    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…

  17. Neuropsychological Effects of Second Language Exposure in Down Syndrome

    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…

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

    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

  19. The effects of low environmental cadmium exposure on bone density

    Recent epidemiological data indicate that low environmental exposure to cadmium, as shown by cadmium body burden (Cd-U), is associated with renal dysfunction as well as an increased risk of cadmium-induced bone disorders. The present study was designed to assess the effects of low environmental cadmium exposure, at the level sufficient to induce kidney damage, on bone metabolism and mineral density (BMD). The project was conducted in the area contaminated with cadmium, nearby a zinc smelter located in the region of Poland where heavy industry prevails. The study population comprised 170 women (mean age=39.7; 18-70 years) and 100 men (mean age=31.9; 18-76 years). Urinary and blood cadmium and the markers of renal tubular dysfunction (β2M-U RBP, NAG), glomerular dysfunction (Alb-U and β2M-S) and bone metabolism markers (BAP-S, CTX-S) as well as forearm BMD, were measured. The results of this study based on simple dose-effect analysis showed the relationship between increasing cadmium concentrations and an increased excretion of renal dysfunction markers and decreasing bone density. However, the results of the multivariate analysis did not indicate the association between exposure to cadmium and decrease in bone density. They showed that the most important factors that have impact on bone density are body weight and age in the female subjects and body weight and calcium excretion in males. Our investigation revealed that the excretion of low molecular weight proteins occurred at a lower level of cadmium exposure than the possible loss of bone mass. It seems that renal tubular markers are the most sensitive and significant indicators of early health effects of cadmium intoxication in the general population. The correlation of urinary cadmium concentration with markers of kidney dysfunction was observed in the absence of significant correlations with bone effects. Our findings did not indicate any effects of environmental cadmium exposure on bone density.

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

    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.

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

    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.

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

    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.

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

    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 ...

  4. RADIOFREQUENCY AND MICROWAVE RADIATION HEALTH EFFECTS AND OCCUPATIONAL EXPOSURE

    Ivana Damnjanović

    2011-12-01

    Full Text Available In the recent years, there have been considerable discussion and concern about the possible hazards of RF/MW radiation. More recently, the growth and development in personal mobile communications have focused attention on the frequencies associated with this technology. A number of studies have examined the health effects of RF/MW electromagnetic fields (EMFs, originating from occupational exposure, hobbies, or residence near the radio or television transmitters. Particularly controversial are the biophysical mechanisms by which these RF fields may affect biological systems. General health effects reviews explore possible carcinogenic, reproductive and neurological effects. Health effects by exposure source have been observed in radar traffic devices, wireless communications with cellular phones, radio transmission, and magnetic resonance imaging (MRI. Several epidemiological surveys have suggested associations with non-specific complaints such as headache, tiredness, sleep disturbance, loss of memory, and dizziness. These findings, which echo reports of illness associated with other types of radiofrequency (RF radiation, relate not only to the use of mobile phones, but also to residence near the mobile phone base stations and other settings involving occupational exposure. The biological effects suggest that some precautions are necessary, and preventive approaches are highly recommended. Further researches are required to give more information about the effects of microwave radiation on our health, especially in occupational setting and professionally exposed workers.

  5. Studies of effects of radiation exposure on children

    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.)

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

    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

  7. Health Effects of Exposure to Low Dose of Radiation

    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)

  8. Health effects assessment of chemical exposures: ARIES methodology

    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

  9. Health effects assessment of chemical exposures: ARIES methodology

    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.

  10. Effects in Plant Populations Resulting from Chronic Radiation Exposure

    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

  11. The Effects of Exposure to Hyperinflation on Occupational Choice

    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. Tobacco Smoke Exposure during Childhood: Effect on Cochlear Physiology

    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.

  13. Effect of environmental exposure to Cadmium on pregnancy outcome

    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.

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

    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...

  15. Respiratory effects of occupational exposure to tobacco dust.

    Viegi, G.; P. L. Paggiaro; Begliomini, E; Vaghetti, E; Paoletti, P; Giuntini, C

    1986-01-01

    Few investigations of the respiratory effects of occupational exposure to tobacco dust have been carried out and the threshold limit value has not well been established. A cross sectional survey on a sample of 223 male and female workers at a cigar and cigarette factory in Lucca (Tuscany) showed a significantly higher prevalence of wheezing, attacks of shortness of breath with wheezing, dyspnoea, and rhinitis than in a reference population. A trend towards a decrease in forced end expiratory ...

  16. Second Language Acquisition. The effect of Age, Exposure and Motivation

    Hildur Þorsteinsdóttir 1987

    2014-01-01

    This paper explores the effect of age, exposure and motivation on SLA. The study of second language acquisition has been a popular subject for many researchers for centuries. According to many researchers, it has been strongly believed that starting second language acquisition at a young age makes a difference in language learning. Researchers claim that younger language learners are better equipped to learn a new language and are more likely to achieve native-like proficiency in the target l...

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

    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. PMID:24903841

  18. Acute effects of acrolein in human volunteers during controlled exposure

    Dwivedi, Aishwarya M.; Johanson, Gunnar; Lorentzen, Johnny C.; Palmberg, Lena; Sjögren, Bengt; Ernstgård, Lena

    2015-01-01

    Abstract Context: Acrolein is a reactive aldehyde mainly formed by combustion. The critical effect is considered to be irritation of the eyes and airways; however, the scarce data available make it difficult to assess effect levels. Objective: The aim of the study was to determine thresholds for acute irritation for acrolein. Methods: Nine healthy volunteers of each sex were exposed at six occasions for 2 h at rest to: clean air, 15 ppm ethyl acetate (EA), and 0.05 ppm and 0.1 ppm acrolein with and without EA (15 ppm) to mask the potential influence of odor. Symptoms related to irritation and central nervous system effects were rated on 100-mm Visual Analogue Scales. Results: The ratings of eye irritation were slightly but significantly increased during exposure to acrolein in a dose-dependent manner (p acrolein alone but not during any of the other five exposure conditions. Conclusion: Based on subjective ratings, the present study showed minor eye irritation by exposure to 0.1 ppm acrolein. PMID:26635308

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

    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

  20. Effects of Graduated Exposure with Feedback of Exposure Times on Snake Phobias

    Becker, Horst G.; Costello, C. G.

    1975-01-01

    The subject-controlled graduated exposure of a snake with feedback of exposure times resulted in significantly less avoidance behaviors for snake-phobic subjects than for control snake-phobic subjects who did not receive therapy. (Author)

  1. Potential exposures and health effects from spent fuel transportation

    The radiation exposures and consequent health effects associated with normal operations and accidents during transportation of spent fuel have been analyzed and evaluated. This study was performed for the U.S. Department of Energy (DOE) as contributory data for response to specific public inquires regarding the Draft Environmental Assessments issued by DOE in 1984. Large quantities of spent fuel from power reactors will be shipped by truck and/or rail from the site of generation or temporary storage to nuclear waste repositories. This transportation activity has the potential for increasing radiation exposures and risks above normal background levels in the vicinity of the transportation route. For normal, accident-free transport of spent fuel, radiation exposures arise from both gamma and neutron sources within the spent fuel cask. U.S. regulations limit the radiation dose equivalent rate to 10 millirem per hour at any point 2 meters from the outer lateral surfaces of the transport vehicle. Computer program PATHRAE-T was developed and employed to determine the total, combined dose field. PATHRAE-T was used to estimate the maximum individual doses from rail cask accidents. The maximum individual exposure, primarily due to inhalation, is about 10 rem and occurs about 70 meters downwind. Ground deposited nuclides account for 99 percent of the population dose. The maximum population dose accident could result in about 22 latent health effects for the urban population. The same case rail cask accidents were also evaluated for a maximum water pathway contamination scenario. The nuclide contaminated plume was assumed to be transported over a large reservoir used for domestic and agricultural water. This accident could result in a 63,000 person-rem dose causing about 13 latent health effects in the absence of any natural and industrial processes for nuclide removal from the water

  2. Effects of Exposure to Advertisements on Audience Impressions

    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.

  3. Radiation-induced stress effects following low dose exposure

    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

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

    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

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

    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

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

    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)

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

    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

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

    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

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

    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)

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

    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

  11. Effective post-exposure treatment of Ebola infection.

    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.

  12. Effects of occupational exposure to tobacco smoke: is there a link between environmental exposure and disease?

    Pacheco, Solange A; Torres, Vukosava M; Louro, Henriqueta; Gomes, Filomena; Lopes, Carlos; Marçal, Nelson; Fragoso, Elsa; Martins, Carla; Oliveira, Cátia L; Hagenfeldt, Manuela; Bugalho-Almeida, António; Penque, Deborah; Simões, Tânia

    2013-01-01

    In a previous study, evidence was provided that indoor secondhand tobacco smoke (SHS) air pollution remains high in Lisbon restaurants where smoking is allowed, regardless of the protective measures used. The aim of this study was to determine in these locations the levels of polycyclic aromatic hydrocarbons (PAH) associated with the particulate phase of SHS (PPAH), a fraction that contains recognized carginogens, such as benzo[a]pyrene (BaP). Data showed that restaurant smoking areas might contain PPAH levels as high as 110 ng/m(3), a value significantly higher than that estimated for nonsmoking areas (30 ng/m(3)) or smoke-free restaurants (22 ng/m(3)). The effective exposure to SHS components in restaurant smoking rooms was confirmed as cotinine levels found in workers' urine. Considering that all workers exhibited normal lung function, eventual molecular changes in blood that might be associated with occupational exposure to SHS and SHS-associated PPAH were investigated by measurement of two oxidative markers, total antioxidant status (TAS) and 8-hydroxyguanosine (8-OHdG) in plasma and serum, respectively. SHS-exposed workers exhibited higher mean levels of serum 8-OHdG than nonexposed workers, regardless of smoking status. By using a proteomics approach based on 2D-DIGE-MS, it was possible to identify nine differentially expressed proteins in the plasma of SHS-exposed nonsmoker workers. Two acute-phase inflammation proteins, ceruloplasmin and inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4), were predominant. These two proteins presented a high number of isoforms modulated by SHS exposure with the high-molecular-weight (high-MW) isoforms decreased in abundance while low-MW isoforms were increased in abundance. Whether these expression profiles are due to (1) a specific proteolytic cleavage, (2) a change on protein stability, or (3) alterations on post-translational modification pattern of these proteins remains to be investigated. Considering that these

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

    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.

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

    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

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

    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

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

    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. Health effect from EMF exposure of Korea population

    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

  18. Health effect from EMF exposure of Korea population

    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

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

    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.

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

    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

  1. Genotoxicity and delayed effects assessment of radiochemical exposures

    Relation of early hemato and genotoxic effects subsequent to the combined exposures of low concentration of lead and mercury salts and γ-radiation low doses with the late effects was studied. The male rats were one-time irradiated by 25 and 50 cGy doses (0.71 Gy/min dose rate). Peculiarities of the effects of lead and mercury ions in combination with radiation low doses were determined. In case of Hg2(NO3)2 intake, one showed the relation of the early postradiation effect at the biochemical level (DNA index changes of blood leucocytes) with population changes of blood granulocytes within 1 month upon irradiation, as well as, correlation of the post-radiation recovery results with reduction of animal lifetime

  2. Radiation in the living environment: sources, exposure and effects

    We are living in a milieu of radiations and continuously exposed to radiations from natural sources from conception to death. We are exposed to radiation from Sun and outer space, radioactive materials present in the earth, house we live in, buildings and workplace, food we eat and air we breath. Each flake of snow, grain of soil, drop of rain, a flower, and even each man in the street is a source of this radiation. Even our own bodies contain naturally occurring radioactive elements. The general belief is that the radiations are harmful and everybody is scared of the same. The cancer is the most important concern on account of exposure to Ionizing Radiation which is initiated by the damage to DNA. The level of exposure depends on the environmental and working conditions and may vary from low to moderate to high and depending on the same the exposed humans can be classified as general public, non nuclear workers (NNW) and nuclear workers (NW). Though, the LNT theory which is considered to be the radiation paradigm considers all radiation at all levels to be harmful and the -severity of the deleterious effect increases with the increase in dose, however, the available literature, data and reports (epidemiological and experimental) speaks otherwise particularly at low levels. The purpose of this paper is to address the question, whether the radiation is harmful at all levels or it is simply media hype and the truth is different, and to promote harmony with nature and to improve our quality of life with the knowledge that cancer mortality rates decrease following exposure to LLIR. Various sources of radiation exposure and the subsequent consequences will be discussed. (author)

  3. Health Effects of Exposure to Radon. BEIR VI

    This National Research Council's report of the sixth Committee on Biological effects of Ionizing Radiations (BEIR VI) addresses the risk of lung cancer associated with exposure to radon and its radioactive progeny. Radon, a naturally occurring gas formed from the decay of uranium in the earth, has been conclusively shown in epidemiologic studies of underground miners to cause lung cancer. There is supporting evidence from experimental studies of animals that confirm radon as a cause of lung cancer and from molecular and cellular studies that provide an understanding of the mechanisms by which radon causes lung cancer. In addition to being present at high concentrations in many types of underground mines, radon is found in homes and is also present outdoors, raising concerns that radon in homes increases lung-cancer risk for the general population. For the purpose of developing public policy to manage the risk associated with indoor radon, there is a need to characterize the possible across the range of exposures received by the population. The BEIR VI committee faced the task of estimating the risks associated with indoor radon across the full range of exposures and providing an indication of the uncertainty to be attached to risk estimates across this range. In preparing this report, the BEIR VI committee, in response to its charge, reviewed the entire body of data on radon and lung cancer, integrating findings from epidemiologic studies with evidence from animal experiments and other lines of laboratory investigation. The committee also considered the substantial evidence on smoking and cancer and the more limited evidence on the combined effect of smoking and radon. The report's elements include comprehensive reviews of the cellular and molecular basis of radon carcinogenesis and of the dosimetry of radon in the respiratory tract, of the epidemiologic studies of miners and the general population, and of the combined effects of radon and other occupational

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

    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.

  5. Predictive modeling of nanomaterial exposure effects in biological systems

    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

  6. Routine medicare and radiation exposure (4) Carcinogenesis and genetic effects by high dose exposure

    The cancer formation and genetic effects induced by high dose radiation (>100 mSv within a short time) (HDR) are easily explained. HDR has a strong carcinogenic activity as historically exemplified from the high prevalence of skin cancer in workers of X-ray tube manufacturing (1902) to that of thyroid cancer in victims exposed to radioiodine at Chernobyl Accident (1986) through increased leukemic prevalence in survivors after A-bomb explosion (1945). In animal experiments, formation of various cancers was found in mice at >100 mGy gamma ray irradiation, but the result cannot be simply extrapolated in human. Atomic Bomb Casualty Commission has been conducting the epidemiological studies of A-bomb survivors, where the risk of cancer death is assessed: e.g., excessive relative risk/Gy is increased in death due to cancers of 9 organs. Significant increase of leukemia and marrow dysplastic syndrome is also observed in the survivors. The studies revealed the effect of age at exposure. Changes in mortality risk due to diseases and in risk of cancer prevalence are not observed in offspring exposed to A-bomb at their fetal stage. Thyroid cancer is increased in children exposed to HRD at Chernobyl accident: the cancer in those exposed at age <15 y reached the peak in 1996 and then decreased, which exhibits the latent phase for cancer formation. Genetic effects of HRD have been examined in animal and genomic experiments. Studies on children of A-bomb survivors have not given the evidence of genetic effect of radiation. ICRP defined the doubling dose, where the genetic effect is doubled, of 5 Sv, (2007) in place of previous 1 Sv (1990). (T.T.)

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

    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.

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

    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.

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

    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

  10. Effect on intelligence of prenatal exposure to ionizing radiation

    Analysis of intelligence test scores at 10 - 11 years of age of individuals exposed prenatally to the atomic bombing of Hiroshima and Nagasaki has revealed the following: 1) For those individuals exposed in the first eight weeks after fertilization or after the 25th week, there is no evidence of a radiation-related effect on intelligence; 2) The mean test scores but not the variances are significantly heterogeneous among exposure categories for individuals exposed at 8 - 15 weeks after fertilization, and to a lesser extent those exposed at 16 - 25 weeks; 3) The regression of intelligence score on estimated fetal tissue dose is linear or linear-quadratic for the 8 - 15 week group and possibly linear for the 16 - 25 week group; 4) The cumulative distributions of test scores suggest a progressive shift downwards in the scores with increasing exposure; and 5) Within the group most sensitive to the occurrence of clinically recognizable, severe mental retardation, individuals exposed 8 to 15 weeks after fertilization, the diminution in intelligence score under the linear-quadratic model is 21 - 27 points at 1 gray (Gy = 100 cGy = 100 rad). The effect is somewhat greater when the controls receiving less than 0.01 Gy are excluded, 33 - 41 points at 1 Gy; but the two estimates are not statistically significantly different. (author)

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

    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.

  12. Thyroid Nodules as a Late Effect of Exposure to Fallout

    Multiple nodules of the thyroid gland have developed in a Marshallese population 10 to 14 years after accidental exposure to radioactive fallout The exposure occurred in 1954 when an unpredicted shift in winds caused deposition of fallout on several Marshall Islands east of Bikini Sixty four people received 175 rads of gamma radiation which proved to be sub lethal but resulted in early nausea and vomiting and significant depression of blood elements Exposure of the skin resulted m beta bums and epilation and there was significant internal absorption of fission isotopes from contaminated food and water The most serious internal exposure was from radioiodines (131I 132I 133I 135I) It was estimated that in addition to the gamma radiation the adult thyroid gland received 160 rads from radioiodines and the young children because of their considerably smaller glands an estimated 700 1400 rads Recovery of blood elements to nearly normal and healing of skin lesions with regrowth of hair was complete by one year These findings have been fully documented The most important late radiation effect has been the development of thyroid abnormalities Since 1963 a total of 20 cases have thus far been detected 17 in children exposed at less than 10 years of age (90% of that group) and 3 in adults Thyroid surgery on 11 children and 3 adults revealed that all had benign adenomatous nodules except for a mixed papillary and follicular carcinoma in a 40 year-old woman The benign nodules were similar to those associated with iodine deficiency but such deficiency was not apparent m the Marshallese who live largely on seafood However most pathologists could not distinguish definite radiation effects in the nodules Growth and development retardation in some of the exposed children is now clearly related to thyroid deficiency Two boys with the greatest growth retardation developed pronounced hypothyroidism with atrophy of their thyroid glands Treatment of the exposed group with thyroid hormone

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

    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...

  14. Dosimetric and exposure reference levels in national and international guidelines/standards for low-frequency electric & magnetic fields

    Contemporary guidelines and standards on exposure to low frequency electric and magnetic fields consider- that induced currents/electric fields inside the human body (principally neural tissues) are relevant dosimetric quantities for setting protective limits against undesirable electrostimulation potentially leading to adverse effects. Additional consideration is given for surface electric charge effects such as discharges and contact currents for exposure to electric fields. These effects, with known interaction mechanisms providing sufficient basis for deriving human exposure limits, differ from effects connecting with the reported association of cancer or other illness with chronic exposure to ambient magnetic fields or proximity to electrical infrastructures The latter are considered associated with proposed- mechanisms that presently do not provide sufficient basis for deriving protective exposure limits. The International Commission on Non-Ionising Radiation Protection (ICNIRP) has published relevant guidelines in 1998 and in 2010, and the Institute of Electrical & Electronic Engineers (IEEE) has published its first standard StdC95.6 in 2002 and reaffirmed in 2007. In Australia, there was NHMRC* 'Interim guidelines on limits of exposure to 50/60Hz electric & magnetic fields' in 1989, and the Australian Radiation Protection & Nuclear Safety Agency (APPANSA) released for public consultation an ELF4 draft standard 'Exposure Limits for Electric & Magnetic Fields - ID Hz to 3 kHz' in 2006&. Its rationale is similar to the international documents with added information on precautionary approach and compliant verification. This paper reviews the historical development and presents a comparison of limits specified in the contemporary national and international standards/ guidelines. Although having a similar principal rationale, there are significant differences in specified dosimetric and exposure reference levels due to variation in available experimental data on

  15. Late biological effects from internal and external exposure

    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.

  16. Late biological effects from internal and external exposure

    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

  17. Joint analysis of French and Czech uranium miners: lung cancer risk at low radon exposure rates and modifying effects of time since exposure and age at exposure

    The present analysis was conducted in the frame of European project 'Quantification of lung cancer risk after low radon exposure and low exposure rate: synthesis from epidemiologic and experimental data'. The overall goal of the project related to uranium miners was the evaluation of lung cancer dose-response relationship and of dose rate effects among European uranium miners exposed to low doses and low dose rates of radon decay products. In addition, modifying factors like attained age, age at exposure and time since exposure were investigated. The joint analysis of French and Czech uranium miners was conducted mainly in order to increase the statistical power and to allow a more detailed description of the variation of dose-response relationship in time. (N.C.)

  18. Effect of Subject Control and Graduated Exposure on Snake Phobias

    Hepner, Alain; Cauthen, Nelson R.

    1975-01-01

    The influence of two of the variables in Leitenberg's graduated exposure technique for treating phobias, graduated exposure and subject control of the exposure time, was investigated using 15 snake-phobic subjects. Subjective fear significantly decreased from pretesting to posttesting. (Author)

  19. The exposure to and health effects of antimony

    Cooper, Ross G.; Harrison, Adrian Paul

    2009-01-01

    . Antimony toxicity is dependent on the exposure dose, duration, route (breathing, eating, drinking, or skin contact), other chemical exposures, age, sex, nutritional status, family traits, life style, and state of health. Chronic exposure to antimony in the air at levels of 9 mg/m3 may exacerbate irritation...

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

    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.

  1. Landscape parameters driving aquatic pesticide exposure and effects

    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

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

    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...

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

    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

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

    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 infectious

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

    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.

  6. Effective exposure level and diagnostic performance in endodontic radiography

    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.

  7. Effective exposure level and diagnostic performance in endodontic radiography

    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

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

    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.

  9. Adverse Effects of Long Term Exposure to Road Traffic Noise

    Kluizenaar, Yvonne

    2015-01-01

    markdownabstract__Abstract__ Road traffic is a prominent source of environmental noise exposure in urbanized areas. Because of its common presence, traffic is a source of exposure that is not easy to avoid. As a consequence, it is affecting a substantial proportion of residents in their homes, and in their living environment more in general. In view of reducing the number of people affected by environmental noise exposure, the European Environmental Noise Directive (END) was adopted in 2002, ...

  10. Adverse effects of long term exposure to road traffic noise

    Kluizenaar, Y. de

    2015-01-01

    Road traffic is a prominent source of environmental noise exposure in urbanized areas. Because of its common presence, traffic is a source of exposure that is not easy to avoid. As a consequence, it is affecting a substantial proportion of residents in their homes, and in their living environment more in general. In view of reducing the number of people affected by environmental noise exposure, the European Environmental Noise Directive (END) was adopted in 2002, geared towards the assessment...

  11. Effects of Tobacco Smoke Exposure in Childhood on Atopic Diseases

    Ciaccio, Christina E.; Gentile, Deborah

    2013-01-01

    Although the smoking prevalence in the United States continues to decline since the Surgeon General’s first report in 1964, certain vulnerable populations continue to be disproportionately affected by the adverse consequences of tobacco smoke exposure. Children are particularly vulnerable to exposure and are likely to suffer from both short- and long-term adverse consequences after early life tobacco smoke exposure. An overwhelming amount of evidence supports an association between asthma dev...

  12. Cell cycle effects for radiosensitivity after heavy ion exposure

    In order to study the relative contribution of the two major DNA double-strand break (DSB) repair pathways, non-homologous end-joining (NHEJ) and homologous recombinational repair (HRR), to the repair of DSBs and non-DSB clustered DNA damage induced by high linear energy transfer (LET) ionizing radiation through the cell cycle, we exposed wild type (WT), NHEJ-deficient, and HRR-deficient Chinese hamster ovary (CHO) cells synchronized by mitotic shake-off to accelerated heavy ions and X-rays. The cell cycle-dependent variation in survival observed in WT cells after X-irradiation was not observed after exposure to 500 MeV/amu iron ions. Non-homologous end joining (NHEJ) and homologous recombinational repair (HRR)-defective cells showed different patterns of cell cycle-dependent radiosensitivity after X-irradiation compared to WT cells, that were likewise significantly attenuated after iron ion exposures. Higher relative biological effectiveness for several other accelerated heavy ions (C, Ne, Si, Ar) of differing LETs was observed for cells exposed in S phase compared to cells exposed in G1. We also observed that HRR deficiency, unlike NHEJ deficiency, did not affect the progression of irradiated G2 cells into mitosis, thus contributing to increased cell killing observed in G2-phase HRR-deficient cells. The HRR-deficient cells showed significantly increased levels of chromatid-type aberrations that correlated with their cell cycle pattern of survival after both X- and iron ion irradiation. Our results suggest that high LET radiation produces not only complex DSBs but also complex non-DSB clustered lesions that specifically require the HRR-mediated repair of these lesions if encountered during DNA replication. In this year, we focused on Fanconi Anemia DNA repair pathway. Only FancA mutant cells showed hypersensitivity to high LET ionizing radiation among other FancC, FancD1, FancD2, and FancG mutant cells. (author)

  13. Cell cycle effects for radiosensitivity after heavy ion exposure

    In order to study the relative contribution of the two major DNA double-strand break (DSB) repair pathways, non-homologous end-joining (NHEJ) and homologous recombinational repair (HRR), to the repair of DSBs and non-DSB clustered DNA damage induced by high linear energy transfer (LET) ionizing radiation through the cell cycle, we exposed wild type (WT), NHEJ-deficient, and HRR-deficient Chinese hamster ovary (CHO) cells synchronized by mitotic shake-off to accelerated heavy ions and X-rays. The cell cycle-dependent variation in survival observed in WT cells after X-irradiation was not observed after exposure to 500 MeV/amu iron ions. Non-homologous end joining (NHEJ) and homologous recombinational repair (HRR)-defective cells showed different patterns of cell cycle-dependent radiosensitivity after X-irradiation compared to WT cells, that were likewise significantly attenuated after iron ion exposures. Higher relative biological effectiveness for several other accelerated heavy ions (C, Ne, Si, Ar) of differing LETs was observed for cells exposed in S phase compared to cells exposed in G1. We also observed that HRR deficiency, unlike NHEJ deficiency, did not affect the progression of irradiated G2 cells into mitosis, thus contributing to increased cell killing observed in G2-phase HRR-deficient cells. The HRR-deficient cells showed significantly increased levels of chromatid-type aberrations that correlated with their cell cycle pattern of survival after both X- and iron ion irradiation. Our results suggest that high LET radiation produces not only complex DSBs but also complex non-DSB clustered lesions that specifically require the HRR-mediated repair of these lesions if encountered during DNA replication. (author)

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

    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...

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

    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...

  16. Effects of Occupational Noise Exposure on 24-Hour Ambulatory Vascular Properties in Male Workers

    Chang, Ta-Yuan; Su, Ta-Chen; Lin, Shou-Yu; Jain, Ruei-Man; Chan, Chang-Chuan

    2007-01-01

    Background Epidemiologic studies have demonstrated that occupational noise exposure is associated with hypertension, but the related mechanism in vascular structural changes is unclear. Objective This panel study aimed to investigate effects of occupational noise exposure on ambulatory vascular structural properties in male workers. Methods We recruited 20 volunteers and divided them into a high-noise–exposure group of 15 and a low-noise–exposure group of 5 based on environmental noise measur...

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

    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...

  18. The obesogenic effect of high fructose exposure during early development

    Goran, Michael I.; Dumke, Kelly; Bouret, Sebastien G.; Kayser, Brandon; Walker, Ryan W.; Blumberg, Bruce

    2016-01-01

    Obesogens are compounds that disrupt the function and development of adipose tissue or the normal metabolism of lipids, leading to an increased risk of obesity and associated diseases. Evidence for the adverse effects of industrial and agricultural obesogens, such as tributyltin, bisphenol A and other organic pollutants is well-established. Current evidence suggests that high maternal consumption of fat promotes obesity and increased metabolic risk in offspring, but less is known about the effects of other potential nutrient obesogens. Widespread increase in dietary fructose consumption over the past 30 years is associated with chronic metabolic and endocrine disorders and alterations in feeding behaviour that promote obesity. In this Perspectives, we examine the evidence linking high intakes of fructose with altered metabolism and early obesity. We review the evidence suggesting that high fructose exposure during critical periods of development of the fetus, neonate and infant can act as an obesogen by affecting lifelong neuroendocrine function, appetite control, feeding behaviour, adipogenesis, fat distribution and metabolic systems. These changes ultimately favour the long-term development of obesity and associated metabolic risk. PMID:23732284

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

    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

  20. Transgenerational effects of paternal exposure to ionizing radiation

    Full text: Paternal F0 irradiation with 1 Gy of attenuated 137Cs gamma rays in CD1 mice 6 weeks prior to conception of F1 offspring involves sperm that were Type B spermatogonia at the time of irradiation. We have demonstrated that this paternal F0 germ cell irradiation affects animal and biochemical endpoints including adult animal body weight, hepatic protein kinase C (PKC) and mitogen-activated protein kinase (MAPK) enzyme activity levels and p53 and p21-waf1 protein levels and in as many as three generations of offspring. These data suggest that irradiated Type B spermatogonia develop a capacity to transmit transgenerational effects that are inherited in a non-Mendelian manner across two or more generations. In this study we have replaced the outbred CD1 strain of mice with the C57BL/6 strain of mice. We now have data that suggests that heritable effects of paternal F0 irradiation of the Type B spermatogonia observed in three successive generations of CD1 mice are also present in the C57BL/6 strain of mice following a paternal F0 radiation exposure using a low dose of ionizing radiation (0.1 Gy attenuated 137-Cs gamma rays). Three generations of offspring from irradiated p53 null and C57BL/6 male mice have been evaluated for effects on animal and biochemical endpoints. The data suggest that the absence of p53 at the time of paternal F0 irradiation may affect the correlative animal and biochemical endpoints evaluated. These biochemical data, together with the results of microsatellite DNA expansion analysis, will provide us with important information regarding the mechanism by which irradiation of the paternal F0 Type B spermatogonia initiates the heritable biological phenotype we have observed and the possible role of genomic instability

  1. Occupational exposure to formaldehyde: effects of years of exposure in the frequency of micronucleus

    Ladeira, Carina; Viegas, Susana; Nunes, Carla; Malta-Vacas, Joana; Gomes, Mário; Mendonça, Paula; Prista, João; Gomes, Manuel C.; Brito, Miguel

    2010-01-01

    Formaldehyde: an important industrial compound used in the manufacture of synthetic resins and chemical compounds such as lubricants and adhesives; also applied as a disinfectant, preservative and in cosmetics productions; relevant workplace exposure to FA also occurs in anatomy, pathology and in mortuaries; classified by IARC as carcinogenic to humans (Group 1), based on sufficient evidence in humans and experimental animals; manifold in vitro studies indicated that FA can induce genotoxic e...

  2. Occupational exposure and effects on the male reproductive system

    Erika Kaltenecker Retto de Queiroz

    2006-03-01

    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.

  3. Occupational exposure and effects on the male reproductive system

    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.

  4. Adverse effects of lactational exposure to chlorpyrifos in suckling rats.

    Mansour, S A; Mossa, A H

    2010-02-01

    The present study was undertaken to evaluate the oxidative damage, biochemical and histopathological alterations in sucking rats whose mothers were exposed to the insecticide chlorpyrifos (CPF). Dams were administered CPF, via oral route. Doses equalled 0.01 mg kg(-1) body weight (b.wt.; acceptable daily intake, ADI), 1.00 mg kg(-1) b.wt. (no observed adverse effects level, NOAEL) and 1.35 mg kg(-1) b.wt. (1/100 lethal dose [LD(50)]) from postnatal day 1 until day 20 after delivery. At two high doses of CPF, the body weight gain and relative liver and kidney weight of suckling pups were significantly decreased. Exposure of the mothers to CPF caused increase in lipid peroxidation (LPO) and decrease in superoxide dismutase (SOD) and glutathione-s-transferase (GST) in lactating pups. CPF altered the level of the marker parameters related to the liver and kidneys. Consistent histological changes were found in the liver and kidneys of the subjected pups, especially at the higher doses. The results suggested that the transfer of CPF intoxication through the mother's milk has resulted in oxidative stress and biochemical and histopathological alterations in the suckling pups. The data of this study may be considered as a contribution to the problem of lactational transfer of the relatively less persistent OP pesticides, such as CPF. PMID:20028704

  5. Immunobiological effect of bitemporal exposure of rabbits to microwaves

    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

  6. Immunobiological effect of bitemporal exposure of rabbits to microwaves

    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.

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

    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

  8. Solar-wind exposure effects in the lunar soil

    This review is primarily devoted to a discussion of solar-wind exposure effects revealed by the study of lunar samples returned to Earth by the Apollo programme. For comparison, a review of data concerning the flux, energy and composition of the solar wind as acquired by direct measurement during space missions, including Apollo, is given. The collection of implanted ions, the damage caused during particle deceleration and sputtering due to the transfer of energy from the incident to target atoms are all considered. Elements not indigenous to the Moon, such as hydrogen, rare gases, carbon and nitrogen, have been studied in detail during lunar soil analysis and evidence in favour of a solar-wind origin for these species is presented. Some difficulties associated with deriving elemental and isotopic compositions of the contemporary and ancient particle flux are outlined. Diffusion loss promoted by impact-induced melting during micrometeorite bombardment is discussed. Some tentative efforts to recognise secular variations in flux, energy and composition of the solar wind are related and the implications of fractionation during sputtering are discussed. 338 references. (author)

  9. Commuters’ air pollution exposure and acute health effects

    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 disproportionately to total daily exposure to traffic related air pollution. So far a limited number of studies compared particulate matter exposures of different groups of commuters. There is limited evid...

  10. The effects of repeated low-dose sarin exposure

    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

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

    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

  12. Effect of radon exposure on superoxide dismutase (SOD) activity in rats

    Effect of radon exposure on the activities of superoxide dismutase (SOD) in blood, kidney, liver and spleen of male Wistar rats were investigated. Radon exposure was carried out in a newly developed chamber with 226Ra as the radon source. SOD activity, measured by the spin trap method using an electron spin resonance spectrometer, increased greatly in liver and kidney after 4 hour exposure whereas it decreased significantly after 16 hour exposure. Despite approximately same total doses by the radon exposure, the stimulated SOD activity after 4 hour exposure was not observed after 16 hour exposure in kidney, liver and spleen except blood, suggesting that the stimulating effect could last for a short period. (author)

  13. Adverse effects of smoke exposure on the upper airway

    Samet, J.

    2004-01-01

    Objective: This paper reviews secondhand smoke (SHS) exposure and diseases and symptoms of the upper airway, including the sinuses. Risks to flight attendants, who were occupationally exposed until smoking was banned on all flights, are emphasised.

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

    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...

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

    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,…

  16. Cardiovascular reactivity and adaptation to recurrent psychological stress: effects of prior task exposure.

    Kelsey, R M; Blascovich, J; Tomaka, J; Leitten, C L; Schneider, T R; Wiens, S

    1999-11-01

    The effects of prior task exposure on cardiovascular reactivity to stress were examined in two experiments by randomly assigning participants to repeated exposure groups that performed mental arithmetic pretest and test tasks versus delayed exposure groups that performed only the test task after prolonged rest. Impedance cardiographic and blood pressure measures were recorded continuously from 60 undergraduate men in Experiment 1 and 112 undergraduate men and women in Experiment 2. Task repetition attenuated cardiovascular reactivity and improved task performance in repeated exposure groups (p < .001), suggesting an integrated process of behavioral adaptation. During the test task, delayed exposure groups showed greater cardiac reactivity (p < .01), but not vascular reactivity, than repeated exposure groups. Thus, cardiac reactivity varied as a specific function of prior task exposure, whereas vascular reactivity varied as a general function of time. PMID:10554594

  17. [Refractory ceramic fibers, kinds, health effects after exposure, TLVs].

    Woźniak, H; Wiecek, E

    1996-01-01

    Ceramic fibres are amorphous or crystalline synthetic mineral fibres which are characterised by refractory properties (i.c. stability in temperature above 1000 degrees C). In general, ceramic fibres are produced from aluminium oxide, silicon oxide and other metal oxides and less frequently from non-oxide materials such as silicon carbide, silicon nitride and boron nitride. In Poland, the production of ceramic fibres was begun in the Refractory Materials Plant, Skawina, during mid-eighties. The production capacity accounts for about 600 tons annually. It is estimated that approximately 3000 persons are exposed to the effect of ceramic fibres in Poland. During the production of ceramic fibres, concentrations of respiral fibres in the air at work places range from 0.07 to 0.27 f/cm3; during the manufacture of ceramic fibre products from 0.23 to 0.71 f/cm3 and during the application of ceramic fibre products from 0.07 to 1.67 f/cm3. As published data depict, fibres longer than 5 microns are most common in the work environment, and the proportion of fibres with diameters below 1 micron accounts for 40-50%. Bearing in mind the present situation in Poland, namely combined exposure to asbestos (during removal of worn out heat-insulating materials) and ceramic fibres (during installation of new insulation), as well as in view of own investigations and literature data which evidence a strong carcinogenic effect of certain fibres, the following MAC values have been adopted: Dusts of refractory ceramic fibres: total dust-2 mg/m3; respirable fibres-1 f/cm3 (L > 5 microns; D < 3 microns; L: D < 3:1) Dusts of reflactory ceramic fibres mixed with asbestos: total dust-1 mg/m3; respirable fibres-1 f/m3. Dusts of refractory ceramic fibres mixed with other man-made mineral fibres (MMMF): total dust-2 mg/m3; respirable fibres-1 f/m3. According to the IARC, ceramic fibres have been included into group 2B-suspected human carcinogen. PMID:8847986

  18. The effect of exposure rate of the growth of soybean seedlings grown from gamma irradiated seeds

    The effect of the gamma (137Cs) total exposure rate of 25 kR delivered at three different exposure rates (887 R/min, 159 R/min and 48 R/min) on soybean seeds was studied by measuring seedling height, cotyledon area, fresh weight, dry weight, Co2 fixation and RuDP carboxylase activity. The dry weight, CO2 fixation and irradiated imbibed groups did not show any correlation with exposure rate. Exposure rate effect was shown for the first stage out, no further correlation was observed in the subsequent stages, probably due to the recovery and repair mechanisms that take place as the seedling increases with age. The absence of an exposure rate effect on irradiated imbibed group may be explained in terms of non-detectable damage at a very high dose, since these seedlings exhibited effects that are similar to the effects of seeds exposed to an acute radiation dose. (author)

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

    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

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

    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

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

    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

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

    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)

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

    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

  4. EFFECTS OF EXPOSURE TO OZONE ON SUSCEPTIBILITY TO EXPERIMENTAL TUBERCULOSIS

    Exposure of mice to 1.96 mg/cu. m. ozone (03) 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 comp...

  5. Commuters’ air pollution exposure and acute health effects

    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

  6. Environmental Tobacco Smoke: Measuring Exposures and Assessing Health Effects.

    National Academy of Sciences - National Research Council, Washington, DC.

    This book evaluates methodologies in epidemiologic and related studies for obtaining measurements of exposure to environmental tobacco smoke (ETS). The book is divided into three parts. The first part discusses physicochemical and toxicological studies of environmental tobacco smoke, including physicochemical nature of smoke and in vivo and in…

  7. Effect of maternal tobacco smoke exposure on the placental transcriptome

    Bruchová, H.; Vašíková, A.; Merkerová, M.; Milcová, Alena; Topinka, Jan; Balaščak, I.; Pastorková, Anna; Šrám, Radim; Brdička, R.

    2010-01-01

    Roč. 31, č. 3 (2010), s. 186-191. ISSN 0143-4004 R&D Projects: GA MŠk 2B06088 Institutional research plan: CEZ:AV0Z50390512; CEZ:AV0Z50390703 Keywords : placenta * gene expression * tobacco smoke exposure Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.985, year: 2010

  8. 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

    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.

  9. Global Screening of Human Cord Blood Proteomes for Biomarkers of Toxic Exposure and Effect

    Colquhoun, David R.; Goldman, Lynn R.; Cole, Robert N.; Gucek, Marjan; Mansharamani, Malini; Witter, Frank R.; Apelberg, Benjamin J.; Halden, Rolf U.

    2008-01-01

    Background Exposures of pregnant women to natural and manmade chemicals can lead to negative health effects in the baby, ranging from low birth weight to developmental defects. In some cases, diseases were postulated to have their basis in toxic exposure in utero or in early childhood. Therefore, an understanding of fetal responses to environmental exposures is essential. To that end, cord blood is a readily accessible biofluid whose proteomic makeup remains mostly unexplored when compared wi...

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

    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...

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

    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...

  12. Silver Exposure in Developing Zebrafish (Danio rerio): Persistent Effects on Larval Behavior and Survival

    Powers, Christina M.; Yen, Jerry; Linney, Elwood A.; Seidler, Frederic J.; Slotkin, Theodore A.

    2010-01-01

    The increased use of silver nanoparticles in consumer and medical products has led to elevated human and environmental exposures. Silver nanoparticles act as antibacterial/antifungal agents by releasing Ag+ and recent studies show that Ag+ impairs neural cell replication and differentiation in culture, suggesting that in vivo exposures could compromise neurodevelopment. To determine whether Ag+ impairs development in vivo, we examined the effects of exposure on survival, morphological, and be...

  13. Currency Hedging in Norwegian Listed Companies: Strategies and Effects on Exposure

    Martinsen, Gustav; Skaarer, Christoffer Branæs

    2012-01-01

    We investigate hedging strategies and foreign exchange rate exposure of Norwegian companies in the seafood and offshore support industries. Factor models building on the Capital Asset Pricing Model are used to analyze stock returns. Results suggest that currency exposure is affected both by company specific features and market wide effects, including oil price influence and speculation in the NOK. Systematic factors, surprisingly, lead to negative exposure to depreciations of the NOK for a ma...

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

    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...

  15. 10 years after Chernobyl, radiation exposure, health effects, safety aspects

    This report sums up the various conferences and symposia which were prompted by the tenth anniversary of the accident in the nuclear power plant of Chernobyl. It was shown that by the accident up to now 31 casualties among the emergency and rescue personal at the site. Offsite no increased number of casualties caused by the accident was observed up to now. In the countries with the highest impact Ukraine, Belarus and Russia, however, an increased number of infant thyroid cancer is observed which is substantially higher than after the nuclear detonations over Japanese cities. Contrary to often published media reports, however, up to now no increases in leukemia or other malignant deceases were observed, neither in the population of the concerned regions nor among the liquidators. The high 137Cs activity concentration in the environment close to the power plant result in exclusion zone even today. The deposition values in Kiev, however, amount to only 30 kBq/m2, in large areas of Ukraine they are below the average values in Austria of 22 kBq/m2. For these areas as well as those outside the former Soviet Union the average doses were less than 1 mSv in the first year, a value which is less than one third of natural annual radiation exposure. Since the reactor accident the activity concentration has significally decreased resulting in an exposure as consequence of the reactor accident of less than 0,8 % of the exposure in the first year. In Austria the exposure in 1996 amounts to less than 0,3 % of natural radiation exposure. (author)

  16. Postexposure effects of brief cadmium, zinc, and phenol exposures on freshwater organisms

    Brent, R.N.; Herricks, E.E. [Univ. of Illinois, Urbana, IL (United States). Dept. of Civil Engineering

    1998-10-01

    Conventional toxicity testing has relied heavily on fixed duration continuous exposure conditions. These conditions have little relevance to the exposure conditions of many environmental pollutants, particularly the highly variable and often brief exposure regimes of episodic pollution events. This research was designed to assess the effects of brief exposures using a postexposure observation period. The common freshwater organisms Ceriodaphnia dubia, Hyalella azteca, and Pimephales promelas were exposed to a range of cadmium (Cd), zinc (Zn), and/or phenol concentrations for durations ranging from 15 to 240 min. Immobility was measured for up to 7 d after the exposure period. Results showed that organisms exposed to Cd and Zn exhibited delayed effects that resulted in increasing immobility for up to 172 h after the exposure period. Ceriodaphnia dubia, H. azteca, and P. promelas exposed to Cd for as short as 30 min exhibited 100, 95, and 85% immobility, respectively, during postexposure observation. Ceriodaphnia dubia and H. azteca exposed to Zn for as short as 30 min exhibited 100 and 30% immobility, respectively, during postexposure observation. Ceriodaphnia dubia exposed to phenol exhibited recovery of mobility after the exposure period. The presence of delayed effects or organism recovery suggests that toxicity tests used to monitor brief exposures should use environmentally relevant exposure durations and postexposure observations.

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

    Govarts, Eva; Remy, Sylvie; Bruckers, Liesbeth; Den Hond, Elly; Sioen, Isabelle; Nelen, Vera; Baeyens, Willy; Nawrot, Tim S; Loots, Ilse; Van Larebeke, Nick; Schoeters, Greet

    2016-01-01

    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. PMID:27187434

  18. Sensory and other neurogenic effects of exposures to airborne office dust

    Mølhave, L.; Kjærgaard, S. K.; Attermann, J.

    This Danish Office Dust Experiment investigated the response of 24 healthy non-sensitive adult subjects to exposure to normal office dust in the air (7 μg m -3 clean air, 136 and 390 μg m -3 TSP). The dust had no major identifiable specific reactive components. The exposure duration was 5 1/4 h and was arranged in a climate chamber in controlled atmospheric conditions. Measurements were made acutely at exposure onset, subacutely at exposure end and next day (late). As secondary aims the time course and threshold of any observed effect of the exposures, and the characteristics of any hyperresponding subgroup were investigated. In a questionnaire with 36 questions the dust exposures caused increased acute, subacute and late perceptions of reduced air quality, acute and subacute increased odor intensity, acute eye irritation, acute and late heavy head, subacute feeling of perspiration, and subacute general irritation. Cough increased subacutely during exposures. In addition, a performance test showed effects of dust exposures which also affected "Mood Scale" ratings. No effect was seen on an addition test for distraction, and objective measurements of skin humidity. The overall conclusion of the study is that healthy subjects without hypersensitivity reactions seem to respond to airborne house dust. The responses are both subjective sensory reactions and other neurogenic effects even at exposure levels within the range found in normal buildings. Some of the effects appeared acutely and decreased through adaptation while others increased during prolonged exposure and remained for more than 17 h after the exposure ended. The findings may indicate for this type of dust a threshold level for the dose-response relationships below 140 μg m -3.

  19. Effect of hydrolysis on identifying prenatal cannabis exposure

    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...

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

    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.

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

    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

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

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

    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...

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

    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

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

    Cock, de, C.C.

    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 work in the orchards. As exposure per unit of time was in the same order of magnitude for Very different tasks such as application and re-entry, individual time spent on different tasks is crucial f...

  5. Exposures and health effects at sea: report on the NIVA course: Maritime Occupational Medicine, Exposures and health Effects at Sea

    Carter, Tim; Jepsen, Jørgen Riis

    2014-01-01

    uncertain validity. This course, run by the NIVA Foundation and supported financially by the Nordic Council of Ministers, provided a first opportunity to draw a wide range of information and experience together to review exposure and health risks in seafarers. As a result it provided both a forum for...

  6. Effect of exposure dose reduction using a compensating filter

    It is empirically said that the application of the compensating filter leads to a decrease in the exposure dose of the filter-inserted area and an increase in that of the otherwise area. Using the area-dosimeter, comparison was made of exposure doses by the application of the above filter and the otherwise filter in head simple X-P, abdominal angiography and lower extremity X-P. Using the filter for head simple X-P and Mix-Dp phantom, measurement was made of the absorbed dose at the 5 cm-depth to compare the rate of decrease in absorbed dose between the above both areas. Head simple X-P gained a decrease in area dose of 29%. The absorbed dose at the 5 cm-depth in the phantom experiment showed a decrease of over 26% at the filter-inserted area, but little increase at the otherwise area. The above results indicated the interposition of the filter between the X-ray tube and the object to lead to decreases not only in the area dose but also in the patient's exposure dose. (author)

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

    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.

  8. Effects of Long Term Exposures on PM Disk Superalloys

    Gabb, T. P.; Sudbrack, C. K.; Draper, S. L.; MacKay, R. A.; Telesman, J.

    2013-01-01

    Turbine disks in some advanced engine applications may be exposed to temperatures above 700 C for extended periods of time, approaching 1,000 h. These exposures could affect the near-surface composition and microstructure through formation of damaged and often embrittled layers. The creation of such damaged layers could significantly affect local mechanical properties. Powder metal disk superalloys LSHR and ME3 were exposed at temperatures of 704, 760, and 815 C for times up to 2,020 h, and the types and depths of environmental attacked were measured. Fatigue tests were performed for selected cases at 704 and 760 C, to determine the impact of these exposures on fatigue life. Fatigue resistance was reduced up to 98% in both superalloys for some exposure conditions. Tensile tests were also performed to help understand fatigue responses, and showed corresponding reductions in ductility. The changes in surface composition and phases, depths of these changed layers, failure responses, and failure initiation modes were compared.

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

    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

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

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

    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

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

    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…

  13. The Effects of Mass Media Exposure on Acceptance of Violence against Women: A Field Experiment.

    Malamuth, Neil M.; Check, James V. P.

    1981-01-01

    Students (N=271) were subjects in an experiment on the effects of exposure to films that portray sexual violence as having positive consequences. Results indicated that exposure to the films portraying violent sexuality increased male subjects' acceptance of interpersonal violence against women. Females exhibited tendencies in the opposite…

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

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

    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…

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

    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 pollu...

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

    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.

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

    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)

  19. Strategy for an Australian research program into possible health issues associated with exposure to communications radiofrequencies

    Telecommunications in Australia has expanded rapidly in recent years. Growth in personal and mobile telecommunications has resulted in the construction of numerous base station antennae. These antennae are highly visible and are often sited in public or high traffic areas. There has also been an increase in the number of mobile phone handsets-the small, low power transmitters held close to the head during use. In the last 2-3 years there has been considerable public concern and media coverage about the possible health effects resulting from exposure to radiofrequency fields or radiofrequency radiation (RFR) which is used for communicating between handsets and base stations. National and international scientific opinion is that at the present time there is no substantiated evidence that exposure to RFR at levels typically found in the community results in adverse health effects but there is a need for further study. Although considerable research has been undertaken on exposure to extremely low frequency (ELF) 50/60 Hz fields, limited information is available on human exposure to RFR in the frequency range 100 kHz to 300 GHz. The frequency bands used for the mobile phone networks are mainly in the 800-900 MHz spectrum region with developing technology using the 1.8-2.2 GHz band. In the digital GSM system pulse modulation occurs at 217 Hz. Radio and television broadcasts are in the 0.3-600 MHz range. Other sources include paging systems, personal communication systems and industrial sources. The discussion paper outlines possible priority areas and makes recommendation for further study under the Australian Research Program

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

    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 (...

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

    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...

  2. EFFECTS OF TRITIUM GAS EXPOSURE ON ELECTRICALLY CONDUCTING POLYMERS

    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

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

    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

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

    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...... highly individual and stable over time. No unequivocal relation between the characteristics of the DPOAE fine structure and the state of hearing could be found. It is suggested to eliminate the DPOAE fine structure in the DPOAE measurement and to establish a reference zero from a large amount of DPOAE...... data, to which individual DPOAE levels can be compared....

  5. Effects of occupational exposure to ionizing radiation on reproductive and child health

    The evidence regarding the effects of occupational exposure to low levels of ionizing radiation on reproductive health is limited. However, exposure to high doses of ionizing radiation is associated with increased risk of adverse reproductive outcomes. The resulting uncertainty about the effects of occupational exposures has caused concern among some workers, therefore, we have designed a study to examine this question among Canadian medical radiation technologists. A short mailed questionnaire will be sent to all CAMRT members to obtain information about reproductive history, and a sample of respondents will receive a second questionnaire requesting information about other important exposures. Occupational dose records will be retrieved from the National Dose Registry. Using this information, relative risks for each outcome will be calculated for different radiation dose levels. This article provides a brief review of the literature on ionizing radiation exposure and reproductive outcomes, and an outline of the proposed study

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

    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

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

    de Vocht, Frank; Olsen, Robert G.

    2016-01-01

    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 50/60-Hz fields, but are generally not measured, are 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 gray 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 (GS) 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. PMID:27066469

  8. Exposure reductions encouraged by the determination of the effective dose equivalent for non-uniform exposures

    DOE Order 5480.11 requires calculation of the effective dose equivalent (EDE) due to non-uniform radiation fields using ICRP-26 weighting factors. To comply with this requirement, Westinghouse Savannah River Company (WSRC) developed a simple dose calculation scheme based on a draft report by the External Dosimetry Working Group of the Health Physics Society Standards Committee. The calculations involved are fairly simple and provide a conservative dose estimate. The resulting EDE estimate provides a much better representation of the risk to the monitored individual than the more prevalent practice of assigning the highest measured dose. Details of the dose assessment methodology are included as an attachment

  9. Effects of Prenatal Alcohol Exposure on the Developing Kidneys

    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.

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

    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...... female offspring of pregnant rats (Mol:WIST) exposed to chronic mild stress (CMS) during gestational days (GD) 9-20, or 1500 ppm toluene, 6 h/day during gestational days 7-20, or a combination of the two. Prenatal CMS was associated with decreased thymic weight and increased auditory startle response....... 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...

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

    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 ...

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

    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

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

    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

  14. Effects of low-level exposure to ionizing radiation: current concepts and concerns for veterinary workers

    The issue of biological effects caused by low-level exposure to ionizing radiation (0.1Sv/yr or 10 rem) is a concern of veterinary radiologists, clinicians and radiotherapists. Cellular damage from ionizing radiation is mediated by injury to DNA, some of which can be repaired. The most important harmful effects attributed to low-level exposure are carcinogenesis and mutation. Ionizing radiation may also cause embryonic and fetal damage, life span shortening and cataractogenesis. The estimated excess risk of mortality for all human cancers is 0.8% (800 deaths per 100,000) per 0.10 Sv of acute exposure; at low dose-rates, risk is presumed to be less. Ionizing radiation increases the frequency of spontaneous genic and chromosomal mutations in man and animals. Studies of atomic bomb survivors imply that at least 1 Sv would be needed to double the spontaneous mutation rate for acute exposure to low-LET radiation. However, the doubling dose for chronic, low-level exposure may be 4 Sv or more. The human embryo and fetus are sensitive to excessive doses of ionizing radiation, with mental retardation the main concern in the low dose range. Paradoxically, there is scientific evidence that in some instances, chronic low-level exposure to ionizing radiation causes a beneficial or hormonic effect. For veterinary workers, occupational exposures appear to be well below the maximum permissible dose limit and the risk or probability of harmful effects is low if stringent radiation safety practices are maintained

  15. Effects of job rotation on musculoskeletal complaints and related work exposures: a systematic literature review.

    Leider, Priscilla C; Boschman, Julitta S; Frings-Dresen, Monique H W; van der Molen, Henk F

    2015-01-01

    The aim of this systematic review was to summarise evidence on the effects of job rotation on musculoskeletal complaints, exposures related to musculoskeletal complaints and sustainable working life parameters. A total of 16 studies were included. No studies on sustainable working life parameters were found. The quality of the studies was assessed using a checklist; eight field studies and three laboratory studies of sufficient quality were used to summarise the following evidence: one field study showed positive results and one field study showed negative results for musculoskeletal complaints, two field studies showed positive results and two field studies showed inconsistent results for exposures, and two field studies showed inconsistent results for musculoskeletal complaints and exposures. Two laboratory studies showed inconsistent results and one laboratory study showed no changes for exposures. In conclusion, there is currently inconsistent evidence for positive or negative effects of job rotation on musculoskeletal complaints and exposures related to musculoskeletal complaints. Practitioner's Summary: Currently, there is inconsistent evidence for recommending job rotation as a strategy for preventing musculoskeletal complaints. Exposures from all involved work activities and body regions should be identified and assessed first, to determine if job rotation provides increased exposure variation and/or beneficial changes in mean exposures related to musculoskeletal complaints. PMID:25267494

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

    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...

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

    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...

  18. Maternal mood and neuroendocrine programming: effects of time of exposure and sex

    Kavita Vedhara; Chris Metcalfe; Heather Brant; Anna Crown; Kate Northstone; Karen Dawe; Stafford Lightman; George Davey-Smith

    2012-01-01

    Rationale/statement of the problem : Adverse exposures that influence growth in prenatal and early postnatal periods are thought to influence vulnerability to chronic diseases via their effects on the neuroendocrine system. In humans, assessment of the underlying mechanisms has been restricted. The aim of the present study was to investigate the effects of adverse early life exposures, specifically maternal mood, on hypothalamic–pituitary–adrenal (HPA) axis, sympathetic nervous ...

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

    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 ...

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

    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 ...

  1. Direct and Indirect Effects of UV-B Exposure on Litter Decomposition: A Meta-Analysis

    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 observ...

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

    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...

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

    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

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

    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.

  5. AS 2008: Arsenic exposure a nd health effects in Inner Mongolia: studies on cardiac, diabetes and cancer-related effects

    Chronic arsenic exposure via drinking water has been of great public health concern world wide. Arsenic exposure has been associated with human cancers, diabetes and cardiovascular diseases. The objectives of this study were to investigate health effects of arsenic and to asses...

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

    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.

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

    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)

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

    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.

  9. Acute effect of copper exposure on serum biochemical characteristics of common carp (Cyprinus carpio L.

    Melika Ghelichpour

    2014-07-01

    Full Text Available Effects of ambient copper was investigated on serum stress markers, sodium and enzyme levels in Common carp (Cyprinus carpio L. over a 14-d exposure period. Fish were exposed to 0, 25 and 100 μg L-1 copper (as copper sulfate and blood was sampled at 0, 3, 7 and 14 d after exposure. Serum profile was significantly affected by copper concentration, sampling time and their interaction. Increase in serum levels of cortisol, glucose, alanine aminotransferase and aspartate aminotransferase and decrease in serum sodium levels were observed in both copper-exposed groups, 3 d after copper exposure, which lasted until the end of the experiment. It is concluded that copper exposure causes stress response and sodium loss in common carp. Likewise alanine aminotransferase and aspartate aminotransferase increase after exposure which might be as results of either tissue damage or stress.

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

    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.

    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.

    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. Effect of UV exposure on rectifying behavior of polyaniline/ZnO heterojunction

    P-type polyaniline (PANI)/n-type ZnO based heterojunction is fabricated and the effect of continuous ultraviolet (UV) exposure on its current–voltage (I–V) characteristics is investigated. The I–V characteristics of PANI/ZnO showed diode-like behavior under dark condition and its ideality factor and barrier height were obtained as 1.54 and 1.35 eV, respectively. For immediate UV exposure the diode showed photo-characteristics, however, during continuous UV exposure diode characteristics started to change with exposure time. After sufficient exposure time characteristics became stable and the ideality factor and barrier height after UV exposure were obtained as 7.94 and 0.92 eV, respectively. It is proposed that the permanent physical changes in PANI film during UV exposure are responsible to change the rectifying behavior. It is found that after 10 min of continuous exposure the PANI film stabilizes and the PANI/ZnO junction shows stable characteristics. (paper)

  14. Effects of orbital exposure on Halar during the LDEF mission

    Brower, William E., Jr.; Holla, Harish; Bauer, Robert A.

    1992-01-01

    Thermomechanical Analysis (TMA), Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA) were performed on samples of Halar exposed on the LDEF Mission for 6 years in orbit and unexposed Halar control samples. Sections 10-100 microns thick were removed from the exposed surface down to a depth of 1,000 microns through the 3 mm thick samples. The TMA and DSC results, which arise from the entire slice and not just its surface, showed no differences between the LDEF and the control samples. TMA scans were run from ambient to 300 C; results were compared by a tabulation of the glass transition temperatures. DSC scans were run from ambient to 700 C; the enthalpy of melting was compared for the samples as a function of section depth with the sample. The TGA results, which arise from the surface of the sample initially, showed a sharp increase in the topmost 50 micron section (the exposed, discolored side) in the weight loss of 170 C in oxygen. This weight loss dropped to bulk values in the range of depth of 50-200 microns. The control sample showed only a slight increase in weight loss as the top surface was approached. The LDEF Halar sample appears to be mechanically undamaged, with a surface layer which oxidizes faster as a result of orbital exposure.

  15. Effects of orbital exposure on Halar during the LDEF mission

    Thermomechanical Analysis (TMA), Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA) were performed on samples of Halar exposed on the LDEF Mission for 6 years in orbit and unexposed Halar control samples. Sections 10-100 microns thick were removed from the exposed surface down to a depth of 1,000 microns through the 3 mm thick samples. The TMA and DSC results, which arise from the entire slice and not just its surface, showed no differences between the LDEF and the control samples. TMA scans were run from ambient to 300 C; results were compared by a tabulation of the glass transition temperatures. DSC scans were run from ambient to 700 C; the enthalpy of melting was compared for the samples as a function of section depth with the sample. The TGA results, which arise from the surface of the sample initially, showed a sharp increase in the topmost 50 micron section (the exposed, discolored side) in the weight loss of 170 C in oxygen. This weight loss dropped to bulk values in the range of depth of 50-200 microns. The control sample showed only a slight increase in weight loss as the top surface was approached. The LDEF Halar sample appears to be mechanically undamaged, with a surface layer which oxidizes faster as a result of orbital exposure

  16. Cold exposure potentiates the effect of insulin on in vivo glucose uptake

    Vallerand, A.L.; Perusse, F.; Bukowiecki, L.J. (Laval Univ. School of Medicine, Quebec (Canada))

    1987-08-01

    The effects of cold exposure and insulin injection on the rates of net 2-({sup 3}H)deoxyglucose uptake (K{sub i}) in peripheral tissues were investigated in warm-acclimated rats. Cold exposure and insulin treatment independently increased K{sub i} values in skeletal muscles, heart, white adipose tissue, and brown adipose tissue. The effects of cold exposure were particularly evident in brown adipose tissue where the K{sub i} increased >100 times. When the two treatments were combined, it was found that cold exposure synergistically enhanced the maximal insulin responses for glucose uptake in brown adipose tissue, all white adipose tissue depots, and skeletal muscles investigated. The results indicate that cold exposure induces an insulin-like effect on K{sub i} that does not appear to be specifically associated with shivering thermogenesis in skeletal muscles, because that effect was observed in all insulin-sensitive tissues. The data also demonstrate that cold exposure significantly potentiates the maximal insulin responses for glucose uptake in the same tissues. This potentialization may result from (1) an enhanced responsiveness of peripheral tissues to insulin, possibly occurring at metabolic steps lying beyond the insulin receptor and (2) an increased tissue blood flow augmenting glucose and insulin availability and thereby amplifying glucose uptake.

  17. Cold exposure potentiates the effect of insulin on in vivo glucose uptake

    The effects of cold exposure and insulin injection on the rates of net 2-[3H]deoxyglucose uptake (Ki) in peripheral tissues were investigated in warm-acclimated rats. Cold exposure and insulin treatment independently increased Ki values in skeletal muscles, heart, white adipose tissue, and brown adipose tissue. The effects of cold exposure were particularly evident in brown adipose tissue where the Ki increased >100 times. When the two treatments were combined, it was found that cold exposure synergistically enhanced the maximal insulin responses for glucose uptake in brown adipose tissue, all white adipose tissue depots, and skeletal muscles investigated. The results indicate that cold exposure induces an insulin-like effect on Ki that does not appear to be specifically associated with shivering thermogenesis in skeletal muscles, because that effect was observed in all insulin-sensitive tissues. The data also demonstrate that cold exposure significantly potentiates the maximal insulin responses for glucose uptake in the same tissues. This potentialization may result from (1) an enhanced responsiveness of peripheral tissues to insulin, possibly occurring at metabolic steps lying beyond the insulin receptor and (2) an increased tissue blood flow augmenting glucose and insulin availability and thereby amplifying glucose uptake

  18. Acute radiation syndrome and delayed effects of radiation exposure

    The results of the overall irradiation of the body with large doses are described. Effects of irradiation are presented separately for central nervous, cardiovascular and gastrointestinal systems. Damages of cellular level and late effects in the whole body scale are shown. 7 refs, 2 figs

  19. Health effects of occupational exposure to crystalline silica in the light of current research results

    Aleksandra Maciejewska

    2014-12-01

    Full Text Available Crystalline silica is commonly found in the work environment. Possible health effects of occupational exposure continue to be the subject of extensive research. The aim of this paper was to analyze the recent findings concerning the health effects of exposure to crystalline silica, taking into account different levels of exposure. This work is based on the relevant information from the papers retrieved from the following databases: EBSCO, Scopus, ScienceDirect, and Web of Science, using the following keywords: crystalline silica, quartz, health effects. The review of the results confirms the multi-faceted harmful effects of crystalline silica. Prolonged occupational exposure, apart from silicosis and non-cancer respiratory diseases, may also result in the development of lung cancer, and autoimmune and chronic kidney diseases, the pathogenesis, which has not been completely explained yet. The exposure to the crystalline silica at concentrations close to the current occupational exposure limit value does not exclude the risk of the following pathologies: silicosis, lung cancer, other lung diseases and renal diseases. It is not feasible to completely eliminate the crystalline silica dust from the work environment. The best way to reduce the health effects of the exposure is to minimize the concentrations of silica dust. Further progress in clarifying the true mechanisms of interaction between silica dust and lung cells, the determination of the importance of surface properties of the silica particles in the pathogenic processes and explaining the effects of co-morbid dust in the work environment may help to prevent the harmful effects of silica dust. Med Pr 2014;65(6:799–818

  20. Biological effects of repeated exposure of beagle dogs to relatively insoluble aerosols of 144Ce. IV

    This experiment is being conducted to study the behavior and long-term biological effects in Beagle dogs of 144Ce inhaled in fused aluminosilicate particles in repeated inhalation exposures for comparison with similar data from dogs that were exposed only once to a similar aerosol. Four groups of nine dogs each were exposed once every eight weeks for two years (13 exposures) to achieve specified exposure goals. The 144Ce-exposed dogs received increasing or relatively constant beta radiation dose rates in contrast to the steadily decreasing dose rate seen after a single inhalation exposure. Exposures in the first and second groups were planned to yield a cumulative absorbed dose to lung of approximately equal to 35,000 rads and those in the third group approximately equal to 17,000 rads within two years after the first exposure. Singly exposed dogs that had died with pulmonary tumors when this experiment was initiated had cumulative doses to death of 29,000 to 61,000 rads. All 13 exposures have been completed. One dog in the 4.5-μCi 144Ce/kg body weight group died at 771 days after first exposure with emaciation, adrenal cortical degeneration and bone marrow aplasia. One control dog died accidentally during anesthesia. During the past year, two additional dogs have died. One dog in the repeated 2.5-μCi 144Ce/kg body weight group died at 1256 days after the first exposure with radiation pneumonitis and pulmonary fibrosis and a control dog died at 1052 days with autoimmune hemolytic anemia. The remaining 32 dogs appear to be in good physical condition except for a persistent lymphopenia at approximately equal to 4 years after the first exposure. They are being maintained for life span observations

  1. Effect of Second-Hand Smoke Exposure on Lung Function among Non-Smoking Korean Women.

    Youngmee Kim; Won-Kyung Cho; EVANGELISTA, LORRAINE S.

    2013-01-01

    Abstract Background: 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. Methods: 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 partici...

  2. Cellular effects and gene expression after exposure to amorphous silica nanoparticles in vitro

    Foldbjerg, Rasmus; Beer, Christiane; Wang, Jing; Sutherland, Duncan S.; Autrup, Herman

    2012-01-01

    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 parallelogr...

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

    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...

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

    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...

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

    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...

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

    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...

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

    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...

  8. Compound extinction: Using the Rescorla-Wagner model to maximize exposure therapy effects for anxiety disorders

    Culver, Najwa C.; Vervliet, Bram; Craske, Michelle G.

    2015-01-01

    Although exposure therapy is an effective treatment for anxiety disorders, fear sometimes returns following successful therapy. The Rescorla-Wagner model predicts that presenting two fear-provoking stimuli simultaneously (compound extinction) will maximize learning during exposure and reduce the likelihood of relapse. Participants were either presented with single extinction trials only or single extinction trials followed by compound extinction trials. Additionally, participants within each ...

  9. Effects of low level exposure to lead on neurophysiological functions among lead battery workers.

    Kovala, T; Matikainen, E; Mannelin, T.; Erkkilä, J; Riihimäki, V; Hänninen, H.; Aitio, A.

    1997-01-01

    OBJECTIVES: Assessment of neurophysiological functions in workers with low level exposure to lead and evaluation of the efficacy of bone lead measurements in the prediction of effects of lead. METHODS: Exposure to lead of 60 workers from a lead battery battery factory was estimated from historical blood lead measurements and analysis of lead in the tibial and calcaneal bones with x ray fluorescence. Peripheral and central nervous system functions were assessed by measuring conduction velociti...

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

    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...

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

    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...

  12. Effects of Social Network Exposure on Nutritional Learning: Development of an Online Educational Platform

    Dagan, Noa; Beskin, Daniel; Brezis, Mayer; Reis, Ben Y.

    2015-01-01

    Background Social networking sites (SNSs) such as Facebook have the potential to enhance online public health interventions, in part, as they provide social exposure and reinforcement. Objective The objective of the study was to evaluate whether social exposure provided by SNSs enhances the effects of online public health interventions. Methods As a sample intervention, we developed Food Hero, an online platform for nutritional education in which players feed a virtual character according to ...

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

    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...

  14. Pregnancy x-rays and childhood cancers: effects of exposure age and radiation dose

    Using data from the Oxford Survey of Childhood Cancers this paper examines the effect of foetal age and number of films used on the subsequent risk of childhood cancer associated with prenatal x-rays. X-rays early in pregnancy were taken for different reasons and required more films when compared with those taken in late pregnancy. Therefore, Mantel-Haenszel techniques were used to estimate the independent effects of (a) exposure age and (b) number of films. Age at exposure had a clearly significant effect; x-rays taken in the first trimester of pregnancy were 2.69 times as effective as x-rays taken in the third trimester. First trimester exposures were often the result of maternal illnesses, so these maternal illnesses were then included among the controlling factors. When this was done the first trimester x-rays were 2.73 times as effective as later exposures. First trimester x-rays were most strongly associated with the cancers which were diagnosed between 4 and 5 years of age. Although the number of films had no detectable effect upon relative risk calculated over all ages, multiple exposures were demonstrably associated with early age at diagnosis. (author)

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

    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.

  16. A study of the effect of nonrandom sampling on the estimation of exposure variability using exposure-time series from the OSHA IMIS health inspection database

    Martinez, L.T.

    1997-05-01

    The objective of this study was to determine the effect of nonrandom sampling over time may have on the estimation of variability, namely the geometric standard deviation, using time series of personal exposure data.

  17. Effects of intrauterine substance and postnatal violence exposure on aggression in children.

    Barthelemy, Olivier J; Richardson, Mark A; Rose-Jacobs, Ruth; Forman, Leah S; Cabral, Howard J; Frank, Deborah A

    2016-05-01

    During the cocaine epidemic of the 1980s and early 1990s, many expressed fears that children with intrauterine cocaine exposure (IUCE) would grow up to be unusually violent. The present study examines the relationship of caregiver reports of school-age children's aggressive behavior with IUCE and postnatal exposure to violence. Respondents were 140 low-income, primarily African American children, ages 8-11, and each child's current primary caregiver from a longitudinal study evaluating potential long term sequelae of IUCE. Multiple regression analyses were used to investigate the independent and interactive effects of level of IUCE (None (n = 69), Lighter (n = 47), Heavier (n =  24)) and exposure to violence (Violence Exposure Scale for Children-Revised) on aggressive behavior (Child Behavior Checklist), while also controlling for other intrauterine substance exposures and additional contextual factors. Children's self-reported exposure to violence was significantly positively associated with caregivers' reports of aggressive behavior (β = 2.17, P = .05), as was concurrent caregiver's psychiatric distress (β = .15, P = .003). However, neither IUCE nor its interaction with exposure to violence showed a significant association with aggressive behavior. Findings suggest the importance of postnatal social environment rather than IUCE in predicting aggressive behavior in childhood. Aggr. Behav. 42:209-221, 2016. © 2015 Wiley Periodicals, Inc. PMID:26660077

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

    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.

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

    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.

  20. Effects of metsulfuron methyl and cypermethrin exposure on freshwater model ecosystems.

    Wendt-Rasch, L; Pirzadeh, P; Woin, P

    2003-05-01

    The aim of this study was to investigate the short-term (2 weeks) effects of the herbicide metsulfuron methyl alone and in combination with the insecticide cypermethrin in freshwater enclosures (80 l). We used a factorial design with four levels of herbicide (0, 1, 5, 20 microg/l) and two levels of insecticide (0 and 0.05 microg/l). The root growth of the macrophyte species Elodea canadensis and Myriophyllum spicatum decreased following exposure to the lowest concentration of metsulfuron methyl tested. Metsulfuron methyl exposure resulted in a decreased pH in the aquatic enclosure at the lowest concentration tested, which is most likely a further indication of decreased macrophyte primary production. The biomass of periphytic algae growing on the leaves of M. spicatum increased in the enclosures exposed to metsulfuron methyl. The species composition of the periphytic algae differed significantly from the controls in the enclosures exposed to 20 microg/l of the herbicide. The increased biomass of periphytic algae on the leaves of the macrophytes is probably an indirect effect of the herbicide exposure. The exposure to metsulfuron methyl possibly induced a leakage of nutrients from the macrophyte leaves, which promoted an increased algal growth. The exposure to metsulfuron methyl did not alter the biomass or the species composition of the phytoplankton community. The zooplankton communities in the enclosures were dominated by rotifers, which were not affected by the exposure to cypermethrin. However, a cypermethrin exposure of 0.05 microg/l initially decreased the abundance of copepod nauplii. Ten days after exposure, the abundance of nauplii was significantly higher in the insecticide-exposed enclosures compared with the non-exposed enclosures. This might be an indication of a sub-lethal stress response, which either increased the number of offspring produced or induced an increased hatching of copepod resting stages. No combined effects of the herbicide and

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

    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

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

    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

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

    A. A. S. Barão; A. L. A. Nencioni; V. A. C. Dorce

    2008-01-01

    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...

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

    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...

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

    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)

  6. Combinative exposure effect of radio frequency signals from CDMA mobile phones and aphidicolin on DNA integrity.

    Tiwari, R; Lakshmi, N K; Surender, V; Rajesh, A D V; Bhargava, S C; Ahuja, Y R

    2008-01-01

    The aim of present study is to assess DNA integrity on the effect of exposure to a radio frequency (RF) signal from Code Division Multiple Access (CDMA) mobile phones. Whole blood samples from six healthy male individuals were exposed for RF signals from a CDMA mobile phone for 1 h. Alkaline comet assay was performed to assess the DNA damage. The combinative exposure effect of the RF signals and APC at two concentrations on DNA integrity was studied. DNA repair efficiency of the samples was also studied after 2 h of exposure. The RF signals and APC (0.2 microg/ml) alone or in synergism did not have any significant DNA damage as compared to sham exposed. However, univariate analysis showed that DNA damage was significantly different among combinative exposure of RF signals and APC at 0.2 microg/ml (p < 0.05) and at 2 microg/ml (p < 0.02). APC at 2 microg/ml concentration also showed significant damage levels (p < 0.05) when compared to sham exposed. DNA repair efficiency also varied in a significant way in combinative exposure sets (p < 0.05). From these results, it appears that the repair inhibitor APC enhances DNA breaks at 2 microg/ml concentration and that the damage is possibly repairable. Thus, it can be inferred that the in vitro exposure to RF signals induces reversible DNA damage in synergism with APC. PMID:19037791

  7. Effects of arsenic trioxide inhalation exposure on pulmonary antibacterial defenses in mice

    The effects of single and multiple (5 and 20) 3-h inhalation exposures to aerosols of arsenic trioxide on the pulmonary defense system of mice were investigated. Arsenic trioxide mist was generated from an aqueous solution and dried to produce particulate aerosols of 0. 4 micron mass median aerodynamic diameter. Aerosol mass concentration ranged from 125 to 1000 micrograms As/m3. Effects of the exposures were evaluated by determination of changes in susceptibility to experimentally induced streptococcal aerosol infection and in pulmonary bactericidal activity to 35S-labeled Klebsiella pneumoniae. Significant increases in mortality due to the infectious challenge and decreases in bactericidal activity were seen after single 3-h exposures to 270, 500, and 940 micrograms As/m3. Similarly, 5 or 20 multiple 3-h exposures to 500 micrograms As/m3 produced consistently significant increases in mortality and decreases in pulmonary bactericidal activity. At 125 or 250 micrograms As/m3, a decrease in bactericidal activity was seen only after 20 exposures to 250 micrograms/m3. Results from earlier studies with an arsenic-containing copper smelter dust were compared to these data. The possibility of the development of adaptation during multiple exposures to arsenic trioxide is also considered

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

    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

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

    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)

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

    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.

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

    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

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

    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.

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

    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

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

    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

  15. Comparative Effectiveness of Guided Mastery and Exposure Treatments for Intractable Phobias.

    Williams, S. Lloyd; And Others

    1984-01-01

    Compared two models of phobia treatment. Severe height and driving phobics (N=32) were assigned to either mastery-oriented treatment based on self-efficacy theory, exposure treatment, or no treatment. Mastery treatment proved to be significantly more effective. Results indicated that treatments effect behavioral change through their intervening…

  16. Modeling the effects of chemical exposure on avian seasonal productivity: Importance of differences in breeding strategies

    Agencies that regulate the use of chemicals are increasingly interested in understanding the magnitude of effects of those chemicals on wildlife populations. While laboratory toxicity tests provide insights into the types of effects caused by chemical exposure, they do not alway...

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

    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...

  18. Effects of Meteorological Conditions on Reactions to Noise Exposure

    Shepherd, Kevin P. (Technical Monitor); Fields, James M.

    2004-01-01

    More than 80,000 residents' responses to transportation noise at different times of year provide the best, but imprecise, statistical estimates of the effects of season and meteorological conditions on community response to noise. Annoyance with noise is found to be slightly statistically significantly higher in the summer than in the winter in a seven-year study in the Netherlands. Analyses of 41 other surveys drawn from diverse countries, climates, and times of year find noise annoyance is increased by temperature, and may be increased by more sunshine, less precipitation, and reduced wind speeds. Meteorological conditions on the day of the interview or the immediately preceding days do not appear to have any more effect on reactions than do the conditions over the immediately preceding weeks or months.

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

    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...

  20. Predictive modeling of nanomaterial exposure effects in biological systems

    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...

  1. Lasting Developmental Effects of Neonatal Fentanyl Exposure in Preweanling Rats

    António Silvério Cabrita; Maria Francelina Lopes; Dora Catré

    2012-01-01

    The present study aimed to determine whether neonatal treatment with fentanyl has lasting effects on stressed developing brain. Six-day-old rats were assigned to one of three groups (10 males/group): (1) fentanyl (incision+fentanyl), (2) saline (incision+0.9% saline), and (3) unoperated (unoperated sham). Pups with a plantar paw incision received repetitive subcutaneous injections of fentanyl or vehicle through postnatal days (PNDs) 6 to 8. A nonoperated sham group served as nonstressed contr...

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

    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...

  3. Immune effects of respiratory exposure to fragrance chemicals

    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...

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

    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

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

    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.

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

    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

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

    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.

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

    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

  9. Chemosensory effects during acute exposure to N-methyl-2-pyrrolidone (NMP).

    van Thriel, Christoph; Blaszkewicz, Meinolf; Schäper, Michael; Juran, Stephanie A; Kleinbeck, Stefan; Kiesswetter, Ernst; Wrbitzky, Renate; Stache, Jürgen; Golka, Klaus; Bader, Michael

    2007-12-10

    Organic solvents are still essential in many industrial applications. To improve safety and health in the working environment lower occupational thresholds limits have been established and less toxic substitutes were introduced. N-Methyl-2-pyrrolidone (NMP) is a versatile solvent that is used as a substitute for dichloromethane in paint strippers. Due to conflicting results, there is a debate whether NMP causes irritations of the upper airways/eyes or not. In a human experimental study we examined the chemosensory effects of NMP under controlled conditions. Fifteen healthy males were investigated in a cross-over study. NMP vapor concentrations were 10, 40 and 80 mg/m(3) for 2 x 4h with an exposure-free lunch break of 30 min. To maximize chemosensory effects a peak exposure scenario (25mg/m(3) baseline, 160 mg/m(3) peaks 4 x 15 min, time-weighted average: 72 mg/m(3)) was tested. The four different conditions were conducted with and without moderate physical workload. Chemosensory effects were measured physiologically by anterior rhinomanometry, eye blink rate and breathing frequency. Subjectively, ratings of acute health symptoms and intensity of olfactory and trigeminal sensations were collected repeatedly throughout the exposures. All physiological variables were unaffected by the different NMP concentrations and even the peak exposures were non-effective on these measures. Olfactory mediated health symptoms increased dose-dependently. For these symptoms a strong adaptation was observable, especially during the first 4h of the exposures. Other acute symptoms were not significantly affected. Comparable to the symptoms, only olfactory sensations increased dose-dependently. Trigeminal sensations (e.g. eye and nose irritations) were evaluated as being barely detectable during the different exposures, only during 160 mg/m(3) exposure peak weak and transient eye irritation were reported. The results clearly suggest that NMP concentrations of up to 160 mg/m(3) caused no

  10. Can we diminish the psychosomatic effects of exposure to nuclear fallout?

    Whitehead, Neil; Hoshi, Masaharu

    2012-01-01

    Radiation in large doses has bad effects on human tissues. The effects have been traced by organisations such as RERF for many decades, and will be further traced following the Fukushima incidents. Those exposed to much smaller amounts, may enter a profoundly negative downwards psychological spiral, and attribute all their problems to such exposure. We propose these effects could be diminished by (1) Indirect education about radiation effects (2) education about the repair mechanisms in the h...

  11. Effects from offshore oil production: chronic exposure of fish to produced water

    Holth, Tor Fredrik

    2009-07-01

    The results of this study demonstrated that environmentally relevant levels of components of produced water may affect condition factor, maturation, biochemical processes and gene expression in fish. The usefulness of bile PAH and AP metabolite measurements to evaluate exposure was demonstrated in two fish species. The development of bio marker responses was shown to depend on exposure regime as well as exposure period. Lysosomal stability (LMS) in cod kidney was related to dose, the effects were observed early (within two weeks) and remained at a stable level throughout the exposure period in fish receiving both continuous and pulsed exposure. Thus, LMS appeared to be a useful marker for effects in Atlantic cod. Formation of DNA adducts in female cod liver was also related to dose, but in contrast to LMS, more than 16 weeks was required for formation of significant levels. This parameter may therefore be underestimated following short-term exposures, such as most offshore fish caging studies (often 4-6 weeks). Although a time-dependent increase was observed, it also required a continuous exposure regime, which is not often observed in the environment. Other bio markers were demonstrated either to adapt or appeared to be insensitive to the exposures. CYP1A activity (EROD) in female cod was responsive on occasion, but a reduction of activity over time was observed. Protein levels of vitellogenin and hepatic CYP1A in zebra fish, as well as AOX in cod kidneys, were not affected in the current study. Gene transcription of several distinct cellular mechanisms was clearly affected in both species, and a predominance of differentially expressed genes in zebra fish was down regulated. This indicated that down-regulation of responsive pathways may be as important or more important than up-regulation. As both presence and absence of effects following pulsed exposure were apparent (DNA adduct formation; oocyte maturation; condition factor), the effects of exposure regime on

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

    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 un investigated. 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.

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

    Max A. Moritz

    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.

  14. Research plan for establishing the effects of time varying noise exposures on community annoyance and acceptability

    Borsky, P. N.

    1980-01-01

    The design of a community noise survey to determine the effects of time varying noise exposures in residential communities is presented. Complex physical and human variables involved in the health and welfare effects of environmental noise and the number-level tradeoffs and time of day penalties are among the factors considered. Emphasis is placed on community reactions where noise exposures are equal in day or evening but differ in the night time, and the effects of ambient noise on more intense aircraft noise exposures. Thirteen different times of day and types of operation situations with exposed populations up to 8-10 miles from the airport are identified. A detailed personal interview questionnaire as well as specific instructions to interviewers are included.

  15. Exposure to low dose radiation and its effect

    The title subjects are easily explained. As an introduction, the concept of the ICRP Recommendation (2007) is explained briefly on its use of radiation protection and management. Natural radiation dose to ordinary Japanese is said to be the average 1.5 mSv/y in contrast to the whole world people, 2.4. Medical radiation dose to Japanese is estimated to amount to 2.3 mSv/y, to American, 3.0, and to people of medically advanced nations, 1.92. There are areas always exposed to the natural high dose radiation like Ramsar 10.2 mSv/y (Iran). The effect of such natural low dose has been shown to be all insignificant on cancer mortality in Yangjian area (3.3 mSv/y) in China, on lung cancer risk due to radon in Japan Misasa spa area (>10 mSv/y), and on cancer mortality among 176 thousands nuclear industry workers in Japan (average accumulated dose 12 mSv), etc. There have been such reports as increased bladder cancer in Chernobyl, increased leukemic relative risk of infants whose fathers worked in Sellafield nuclear facility, and acute death/health-injury of residents in the past Lou-Lan area where Chinese nuclear bombs were tested. Fallout data from 1955 to 2011 shows the process of radioactive materials fallen and peaks were due to nuclear tests and Chernobyl/Fukushima Accidents. Basic studies on low dose effect involve those of the radioadoptive response, radiation hormesis, bystander effect and cluster injury of DNA. In low dose-carcinogenesis relationship, presented are models of linear non-threhold (LNT), those estimating lower risk than LNT like linear quadratic (LQ) model, and higher risk like supra-linear model. Risks leading to cancer formation include the occupation and others like medical doctors, tobacco smoking and various anxieties/stresses. (T.T.)

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

    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

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

    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 ...

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

    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 ...... WHO and EU it can be estimated that this increased level is associated with an annual increase in mortality of about 200 extra deaths, about 160 extra cases of hospital admissions due to respiratory diseases, and about 60 new cases of chronic bronchitis in the DK....

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

    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

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

    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.

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

    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.

  2. Neurobehavioral effects during exposures to propionic acid--an indicator of chemosensory distraction?

    Hey, Kathrin; Juran, Stephanie; Schäper, Michael; Kleinbeck, Stefan; Kiesswetter, Ernst; Blaszkewicz, Meinolf; Golka, Klaus; Brüning, Thomas; van Thriel, Christoph

    2009-11-01

    The chemosensory effects of propionic acid (PA) in humans have not been conclusively studied and there is no established occupational exposure limit (OEL) in Germany. In addition to sensory irritation caused by PA, it was hypothesized that the annoying odor of PA might interfere with the performance results. There were 23 consenting healthy participants (12 female, 11 male) in the group studied. They were exposed for 4 h to PA in concentrations of 0.3, 5 and 10 ppm in a cross-over design. During these exposures, performance was recorded with four cognitive tests measuring response-inhibition, working memory, set-shifting, and divided attention. Odor annoyance, other chemosensory sensations, and acute symptoms were assessed before, during, and after exposure with standardized rating scales. Moderate odor annoyance and weak sensory irritation were reported during 5 and 10 ppm exposure conditions. The different levels of exposure to PA had no impact upon the results of three out of the four behavioral tests. The difficulties of the task were reflected in the results. However in the fourth, which was the response-inhibition task, there was significant increase in the error rates which corresponded to the exposure levels. Results from previous experiments suggested high odor annoyance at the investigated concentrations. Our findings showed that odor annoyance and reported sensory irritations were low. In conclusion, the hypothesis of a distractive effect due to the malodor of PA could not be confirmed. Only in concentrations as high as 10 ppm acute PA exposure affected the response accuracy of one of the four neurobehavioral task. For other more annoying substances, a neurobehavioral effect influenced by an indirect mechanism of resources competition is still conceivable. PMID:19733590

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

    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.

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

    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…

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

    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.

  6. Effect of ionising radiation exposure on structure and permeability of epithelial junctions in rat ileum

    Exposure of the digestive tract to ionising radiation results in both morphological and functional alterations of the small intestine. However little is known about the effect of irradiation on the junctions playing a major role in the maintenance of epithelial barrier integrity. Thus the aim of this study was to investigate, in rat ileum, the effect of radiation exposure on the permeability of the epithelial barrier in parallel with the localization of certain inter- and intra-cellular proteins of tight and adherent junctions

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

    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.

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

    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

  9. [The favorable effect of humic acid based complex micro-element preparations in cadmium exposure].

    Hudák, A; Náray, M; Nagy, I; Molnár, M; Gömöry, I; Ungváry, G

    1997-06-01

    The authors have studied the effect of consumption of a humic acid based complex microelement preparation (potassium, magnesium, iron, zinc, manganese, copper, vanadium, cobalt, molibden, selenium bound to humic acids) for six weeks (10 ml daily) on the biological exposure indices (blood and urine cadmium levels) and clinical laboratory parameters (liver and kidney tests, blood picture) of men (n = 18; 39.7 +/- 10.4 years of age;) working in cadmium exposure for 8.3 +/- 5.0 years. The initial mean blood and urine cadmium levels of the non-smoking subjects was twice higher than that of the non-smoking male controls living in the same urban area (n = 35), and significantly correlated with the length of exposure. Their mean serum alanin-aminotransferase, gamma-glutamyl-transferase, creatinine, uric acid and urinary N-acetyl-beta-D-glucosaminidase levels were significantly higher than that of the controls. After the six-week treatment blood cadmium level, activity of serum alanin-aminotransferase, serum uric acid and urinary protein concentrations decreased significantly, the abnormal serum iron levels normalized. According to this results, the absorption of cadmium decreased on the effect of the complex microelement supplementation and the adverse laboratory changes attributable partly to cadmium exposure improved. Therefore humic acid based complex microelement supplementation is recommended as an effective tool for prevention and health protection in occupational cadmium exposure as well as for smokers known to be considerably burdened by cadmium. PMID:9254361

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

    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)

  11. The effect of air exposure on palladium-copper composite membranes

    It was found that when electrolessly deposited thin Pd and Pd-Cu membranes were exposed to air at temperatures above 350 degree sign C, their H2 flux increased substantially immediately after the air exposure, then decreased to a new steady-state value. While this was a quasi-reversible change for the H2 flux, the flux of insoluble species, such as N2, irreversibly increased with every air exposure but by a much smaller extent. The extent of these changes was found to be dependent on the exposure time and the temperature of the tests. Thus, we decided to investigate the effect of gas exposures on the properties of these materials. Palladium and palladium-copper films, prepared by electroless deposition on ceramic supports, and commercial foils were exposed to air, hydrogen and helium at 500 and 900 degree sign C for times varying from 1 h to 1 week with the objective of determining the effect of the different exposure conditions on the surface morphology, the flux of different penetrants and the crystalline structure of the materials. Atomic force microscopy (AFM) and X-ray diffraction (XRD) were used to study the changes occurring in the films under those conditions. It was observed that the exposure of both the electroless films and the foils to hydrogen and air markedly modified their surface morphology. The hydrogen exposure tended to smooth the surface features whereas the oxygen exposure created new surface features such holes and large peaks. Additionally it was found that the air exposure produced some oxidation of the film to create PdO. These results suggested that a common hypothesis stating that air oxidation just cleans the surface of the membrane might not be sufficient to explain all of those changes. A contributing effect of air exposure may be the increase in surface area due to the formation of palladium oxide. However, the extent of the surface area increase was insufficient to explain the increase in steady-state H2 flux

  12. The effects of exposure to environmental factors on Heart Rate Variability: An ecological perspective

    The impact of human exposure to environmental factors on Heart Rate Variability (HRV) was examined in the urban space of Tel-Aviv-Jaffa. Four environmental factors were investigated: thermal and social loads; CO concentrations and noise. Levels of HRV are explained mainly by subjective social stresses, noise and CO. The most interesting result is the fact that while subjective social stress and noise increase HRV, low levels of CO are reducing HRV to some extent moderating the impact of subjective social stress and noise. Beyond the poisoning effect of CO and the fact that extremely low levels of HRV associated with high dozes of CO increase risk for life, low levels of CO may have a narcotic effect, as it is measured by HRV. The effects of thermal loads on HRV are negligible probably due to the use of behavioral means in order to neutralize heat and cold effects. -- Highlights: ► The impact of human exposure to environmental factors on Heart Rate Variability (HRV) was examined. ► Previous studies measured human exposure to pollution by fixed monitoring stations. ► This study measured actual personal exposure by mini sensors. ► High level of subjective social load and noise increase HRV. ► Low levels of CO may have a narcotic effect, as it is measured by HRV. -- The research focuses on the effects of environmental factors; noise, subjective social stress, thermal load and CO on Heart Rate Variability

  13. Protective effects of quercetine on the neuronal injury in frontal cortex after chronic toluene exposure.

    Kanter, Mehmet

    2013-08-01

    The aim of this study was designed to evaluate the possible protective effects of quercetine (QE) on the neuronal injury in the frontal cortex after chronic toluene exposure in rats. The rats were randomly allotted into one of the three experimental groups, namely, groups A (control), B (toluene treated) and C (toluene-treated with QE), where each group contains 10 animals. Control group received 1 ml of normal saline solution, and toluene treatment was performed by the inhalation of 3000 ppm toluene in an 8-h/day and 6-day/week order for 12 weeks. The rats in QE-treated group was given QE (15 mg/kg body weight) once a day intraperitoneally for 12 weeks, starting just after toluene exposure. Tissue samples were obtained for histopathological investigation. To date, no histopathological changes of neurodegeneration in the frontal cortex after chronic toluene exposure in rats by QE treatment have been reported. In this study, the morphology of neurons in the QE treatment group was well protected. Chronic toluene exposure caused severe degenerative changes, shrunken cytoplasm and extensively dark picnotic nuclei in neurons of the frontal cortex. We conclude that QE therapy causes morphologic improvement in neurodegeneration of frontal cortex after chronic toluene exposure in rats. We believe that further preclinical research into the utility of QE may indicate its usefulness as a potential treatment on neurodegeneration after chronic toluene exposure in rats. PMID:22252859

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

    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

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

    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)

  16. Effect of alcohol exposure on fetal brain development

    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.

  17. Interoceptive hypersensitivity and interoceptive exposure in patients with panic disorder: specificity and effectiveness

    Funayama Tadashi

    2006-08-01

    Full Text Available Abstract Background Interoceptive exposure has been validated as an effective component of cognitive behavioral therapy (CBT for the treatment of panic disorder but has hitherto received little research attention. We examined the effectiveness of various interoceptive exposure exercises using the Body Sensations Questionnaire (BSQ (Chambless et al., 1984. Methods We first performed an exploratory principal factor analysis of all the items contained in the BSQ to obtain meaningful dimensions of interoceptive fears. Next, we examined the correlations between each interoceptive exposure task's degree of similarity to panic attacks and each BSQ factor and then examined whether the BSQ factor scores decreased in comparison with the baseline values when the corresponding exposure tasks were successfully completed by the subjects. Results The factor analyses revealed four factors, which we named "pseudoneurological fears", "gastrointestinal fears", "cardiorespiratory fears" and "fears of dissociative feelings." Among the nine interoceptive exposure tasks, 'hyperventilation', 'shaking head', 'holding breath' and 'chest breathing' were considered to reproduce pseudoneurological symptoms, 'breathing through a straw' was considered to reproduce gastrointestinal symptoms, and 'spinning' was considered to reproduce both pseudoneurological and dissociative symptoms; none of the interoceptive exercises were found to reproduce cardiorespiratory symptoms. Among each group of patients for whom 'hyperventilation', 'holding breath', 'spinning' or 'chest breathing' was effective, a significant improvement in the BSQ pseudoneurological fears factor scores was observed. On the other hand, no significant difference between the baseline and endpoint values of the BSQ gastrointestinal fears or the BSQ fears of dissociative feelings factor scores were observed among the patients for whom 'spinning' or 'breathing through a straw' was effective. Conclusion Several

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

    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

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

    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±7.5μg/L for +As treatment and 34.4±1.4μg/L for B+As treatment for 56days. 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 (56days), 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 150μg/L and closer to the water quality criteria to protect aquatic life recommended by the Canadian government which is 5μg As/L. PMID:26657392

  20. Comparative toxicological studies on the effects of internal exposures

    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)

  1. The effects of oil sands wastewater on fish resulting from exposure to sub-lethal concentrations

    Rainbow trout, Oncorhynchus mykiss, were exposed to sub-lethal concentrations of oil sands wastewater in flow through laboratory experiments as well as to artificial ponds containing sub-lethal concentrations of tailings pond water and fine tails in order to study the viability of the wet landscape remediation option. Large (200--300 g) fish were used for all the exposures in this preliminary study and the following data were collected: blood cell counts, sex hormone concentrations, sexual maturation, stress protein concentrations, PAH-metabolites in bile, condition factors, liver somatic indices, mixed function oxygenase induction, PAHs in muscle, external condition and the condition of internal organs. The data obtained from this study revealed no adverse effects upon fish during extended field exposures. Given similar exposure conditions in the release waters of a wet landscape reclamation, the data suggest that there may be no adverse effects upon fish, however, longer term studies, other indicator organisms and additional chronic tests should be conducted

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

    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)

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

    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

  4. Developmental exposure to terbutaline alters cell signaling in mature rat brain regions and augments the effects of subsequent neonatal exposure to the organophosphorus insecticide chlorpyrifos

    Exposure to apparently unrelated neurotoxicants can nevertheless converge on common neurodevelopmental events. We examined the long-term effects of developmental exposure of rats to terbutaline, a β-adrenoceptor agonist used to arrest preterm labor, and the organophosphorus insecticide chlorpyrifos (CPF) separately and together. Treatments mimicked the appropriate neurodevelopmental stages for human exposures: terbutaline on postnatal days (PN) 2-5 and CPF on PN11-14, with assessments conducted on PN45. Although neither treatment affected growth or viability, each elicited alterations in CNS cell signaling mediated by adenylyl cyclase (AC), a transduction pathway shared by numerous neuronal and hormonal signals. Terbutaline altered signaling in the brainstem and cerebellum, with gender differences particularly notable in the cerebellum (enhanced AC in males, suppressed in females). By itself, CPF exposure elicited deficits in AC signaling in the midbrain, brainstem, and striatum. However, sequential exposure to terbutaline followed by CPF produced larger alterations and involved a wider spectrum of brain regions than were obtained with either agent alone. In the cerebral cortex, adverse effects of the combined treatment intensified between PN45 and PN60, suggesting that exposures alter the long-term program for development of synaptic communication, leading to alterations in AC signaling that emerge even after adolescence. These findings indicate that terbutaline, like CPF, is a developmental neurotoxicant, and reinforce the idea that its use in preterm labor may create a subpopulation that is sensitized to long-term CNS effects of organophosphorus insecticides

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

    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.

  6. Ecotoxicological effects on the earthworm Eisenia fetida following exposure to soil contaminated with imidacloprid.

    Zhang, Qingming; Zhang, Baohua; Wang, Caixia

    2014-11-01

    Imidacloprid, a neonicotinoid insecticide, has been used widely in agriculture worldwide. The adverse effects of imidacloprid on exposed biota have brought it increasing attention. However, knowledge about the effects of imidacloprid on antioxidant defense systems and digestive systems in the earthworm is vague and not comprehensive. In the present study, the changes in the activity of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), cellulase, reactive oxygen species (ROS), and malondialdehyde (MDA) in the earthworm Eisenia fetida exposed to artificial soil treated with imidacloprid were examined systematically. The results showed that the activity of these biomarkers was closely related to the dose and duration of the exposure to imidacloprid. The activity of SOD was stimulated significantly at doses of 0.66 and 2 mg kg(-1) imidacloprid but markedly inhibited at a dose of 4 mg kg(-1) imidacloprid with prolonged exposure. The activities of CAT and POD increased irregularly at 0.2-4 mg kg(-1) imidacloprid over different exposure times. The level of ROS at a dose of 2 or 4 mg kg(-1) imidacloprid was significantly increased over the entire exposure period. When the concentration of imidacloprid was above 0.66 mg kg(-1), the balance of the activity of the antioxidant enzymes and ROS level was interrupted. The activity of cellulase decreased significantly with prolonged exposure. At the stress of 4 mg kg(-1) imidacloprid, the content of MDA was significantly increased with increasing exposure time. The results of the present study suggest that imidacloprid has a potentially harmful effect on E. fetida and may be helpful for assessment of the risk of imidacloprid to the soil ecosystem environment. However, to obtain more comprehensive toxicity data, it is necessary to investigate the effects of imidacloprid on earthworm using native soils in the future work. PMID:24938817

  7. Effect of chronic lead exposure on kidney function in male and female rats: determination of a lead exposure biomarker.

    Ghorbe, F; Boujelbene, M; Makni-Ayadi, F; Guermazi, F; Kammoun, A; Murat, J; Croute, F; Soleilhavoup, J P; El-Feki, A

    2001-12-01

    Several cytotoxic chemical pollutants inducing peroxidative damages are liable to induce kidney failure. Among these pollutants we find heavy metals such as: lead, nickel, cadmium, vanadium and mercury. Lead is one of the most dangerous metals because it is widely spread in the environment, and because it may be a source of several nervous diseases. The aim of this study is to provide evidence concerning the effect of this metal on the renal function and to try to determine a storage corner in the organism which serves as an indicator of a lead intoxication. Lead acetate was administered by oral route in the drinking water to adult rats aged three months at the rate of 0.3% (P1) and 0.6% (P2). Reference rats received distilled water to drink under the same conditions. The treatment continued for 15, 30, 45, 60 and 90 days. The creatinemia, uremia, glycemia and creatinuria are determined by colorimetric techniques. Lead concentration in blood as well as the lead content of the tail are determined by atomic absorption after nitroperchloric mineralization at the liquid stage. The results showed an increase of creatinemia on the 30th day of the experiment for both sexes in (P1 and P2). The same happened for ureamia. The increase of these two parameters would indicate a renal deficiency which is confirmed by a decrease of creatinuria and urinary pH observed mainly on and after the 45th day of the experiment. An increase of the renal relative weight was noticed in P1 and P2 on the 30th day of the treatment. The determination of the concentration of lead in the blood shows that this factor increases among treated subjects in a constant way, independently of the dose and the duration of the treatment. Nevertheless, the rate increase of lead in the tail seems to be dose-dependent. In conclusion, lead administered by oral route causes a renal deficiency to the rat without distinction between males and females. In addition, the tail seems to be a reliable exposure biomarker

  8. Effect of sorption on exposures to organic gases from environmental tobacco smoke (ETS)

    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

  9. Effect of sorption on exposures to organic gases from environmental tobacco smoke (ETS)

    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.

  10. Effects of embryonic exposure to polychlorinated biphenyls (PCBs) on larval zebrafish behavior.

    Lovato, Ava K; Creton, Robbert; Colwill, Ruth M

    2016-01-01

    Developmental disorders such as anxiety, autism, and attention deficit hyperactivity disorders have been linked to exposure to polychlorinated biphenyls (PCBs), a ubiquitous anthropogenic pollutant. The zebrafish is widely recognized as an excellent model system for assessing the effects of toxicant exposure on behavior and neurodevelopment. In the present study, we examined the effect of sub-chronic embryonic exposure to the PCB mixture, Aroclor (A) 1254 on anxiety-related behaviors in zebrafish larvae at 7 days post-fertilization (dpf). We found that exposure to low concentrations of A1254, from 2 to 26 h post-fertilization (hpf) induced specific behavioral defects in two assays. In one assay with intermittent presentations of a moving visual stimulus, 5 ppm and 10 ppm PCB-exposed larvae displayed decreased avoidance behavior but no significant differences in thigmotaxis or freezing relative to controls. In the other assay with intermittent presentations of a moving visual stimulus and a stationary visual stimulus, 5 ppm and 10 ppm PCB-exposed larvae had elevated baseline levels of thigmotaxis but no significant differences in avoidance behavior relative to controls. The 5 ppm larvae also displayed higher terminal levels of freezing relative to controls. Collectively, our results show that exposure to ecologically valid PCB concentrations during embryonic development can induce functional deficits and alter behavioral responses to a visual threat. PMID:26561944

  11. Health effects of occupational exposure to static magnetic field in a chloralkali plant

    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.

  12. Effects of methylmercury and alcohol exposure in Drosophila melanogaster: Potential risks in neurodevelopmental disorders.

    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

  13. Longitudinal Effects of Embryonic Exposure to Cocaine on Morphology, Cardiovascular Physiology, and Behavior in Zebrafish.

    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

  14. The mere exposure effect depends on an odour’s initial pleasantness

    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.

  15. The mere exposure effect depends on an odor’s initial pleasantness

    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

  16. Allergy arising from exposure to airborne contaminants in an insect rearing facility: Health effects and exposure control

    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.

  17. Reduction of implantation shadowing effect by dual-wavelength exposure photo process

    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 ...

  18. State-of-the-art exposure chamber for highly controlled and reproducible THz biological effects studies

    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.

  19. Bringing together Scientific Disciplines to better understand the health effects of Occupational Exposure to uranium

    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)

  20. Evaluating chemical exposure and effect models for aquatic species with a focus on crude oil constituents

    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

  1. Cumulative Effects of Exposure to Violence on Posttraumatic Stress in Palestinian and Israeli Youth

    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…

  2. 40 CFR 79.60 - Good laboratory practices (GLP) standards for inhalation exposure health effects testing.

    2010-07-01

    ... the CAA, it shall be a violation of this section and a violation of this rule (40 CFR part 79, subpart... under 40 CFR part 79 and may require the sponsor to develop data in accordance with the requirements of...) standards for inhalation exposure health effects testing. 79.60 Section 79.60 Protection of...

  3. A Meta-Analysis Summarizing the Effects of Pornography II: Aggression after Exposure.

    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…

  4. Treatment of Severe Social Phobia: Effects of Guided Exposure with and without Cognitive Restructuring.

    Mattick, Richard P.; Peters, Lorna

    1988-01-01

    Assigned social phobics with severe scrutiny fears to therapist-guided exposure without and including cognitive restructuring. Found the combined condition significantly more effective in endstate functioning, in increasing behavioral approach, and in decreasing self-rated avoidance. Treatment-induced changes in fear of negative evaluation,…

  5. Effects of Age of English Exposure, Current Input/Output, and Grade on Bilingual Language Performance

    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…

  6. The Role of Exposure Condition in the Effectiveness of Explicit Correction

    Yilmaz, Yucel

    2016-01-01

    This article reports on a study that investigated the effects of two feedback exposure conditions on the acquisition of two Turkish morphemes. The study followed a randomized experimental design with an immediate and a delayed posttest. Forty-two Chinese-speaking learners of Turkish were randomly assigned to one of three groups: receivers,…

  7. Morphologic and Immunologic effects in the rat after prenatal exposure to Cyclophosphamide

    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

  8. Discussion about modeling the effects of neutron flux exposure for nuclear reactor core analysis

    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

  9. Effects of prenatal exposure to xylene on postnatal development and behavior in rats

    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 not...

  10. Effects of prenatal exposure to toluene on postnatal development and behavior in rats

    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...

  11. Effects of lung exposure to carbon nanotubes on female fertility and pregnancy. A study in mice

    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. Antepartum and Postpartum Exposure to Maternal Depression: Different Effects on Different Adolescent Outcomes

    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…

  13. Exposure-response functions for health effects of air pollutants based on epidemiological findings

    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

  14. Co-Exposure with Fullerene May Strengthen Health Effects of Organic Industrial Chemicals

    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...... which can be used with fullerene as reagents or solvents in industrial processes. Potential co-exposure scenarios include a fullerene dust and organic chemical vapor, or a fullerene solution aerosolized in workplace air. Unfiltered and filtered mixtures of C-60 and organic chemicals represent different...

  15. The effects of Fhit on tumorigenesis after multi-exposure to low-dose radiation

    Yu, Xiaoyan; Lu, Lin; Wen, Siyuan; Wang, Ya

    2009-01-01

    Low-dose (≤ 0.1 Gy) radiation could reduce high-dose induced damage including tumorigenesis. However, it remains unclear whether multi-exposure to low-dose radiation at a high dose rate has any risk for increasing tumorigenesis, and whether Fhit plays any role in the process. The purpose of this study is to investigate the effects of multi-exposure to low-dose radiation at a high dose rate on tumorigenesis, and the role of Fhit in it. We irradiated Fhit+/+ and Fhit-/- mice with 1 Gy/1 or 0.1 ...

  16. Effects of maternal exposure to nano-alumina during pregnancy on neurodevelopment in offspring mice

    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

  17. Dietary acrylamide exposure among Finnish adults and children: The potential effect of reduction measures

    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 ...

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

    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......, pesticides, u.v.-filters, bisphenol A, parabens, and the drug paracetamol. The groups received vehicle (control), a mixture of all 13 chemicals at 150-times (TotalMix150) or 450-times (TotalMix450) high-end human exposure, or 450-times a mixture of nine predominantly anti-androgenic chemicals (AAMix450...

  19. Relative biological effectiveness (RBE) of fission neutrons and gamma rays at occupational exposure levels

    The pathologic consequences of exposure to 60 equal once-weekly doses of fission neutron or 60Co gamma rays have been subjected to dose-response analyses for the purposes of generating relative biological effectiveness (RBE) values for the major causes of death of for tumor occurrences. Cumulative probabilities of death or occurrence were generated for 15 categories of neoplastic disease for the time interval of 800--999 days since first exposure. These probabilities were developed for each dose, sex, and radiation quality, and a dose-response analysis was applied to derive linear risk coefficients of death or occurrence. 40 refs., 16 figs., 9 tabs

  20. Effect of honey supplementation on toxicity of gasoline vapor exposure in rats

    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

  1. Multi-generational effects of polybrominated diphenylethers exposure: embryonic exposure of male American kestrels (Falco sparverius) to DE-71 alters reproductive success and behaviors.

    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

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

    Hemmingsen, Jette Gjerke; Hougaard, Karin Sørig; Talsness, Chris; Wellejus, Anja; Loft, Steffen; Wallin, Håkan; Møller, Peter

    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 of...... action. Dams inhaled 20 mg/m(3) of diesel exhaust particle standard reference material 2975 (SRM2975) or clean air for 1h/day on day 7-19 during pregnancy. Male offspring were killed on day 170 after birth. The dams that had inhaled SRM2975 delivered offspring, which in adulthood had reduced daily sperm...... 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...

  3. Dose Effects of Ion Beam Exposure on Deinococcus Radiodurans: Survival and Dose Response

    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.

  4. Effects of space flight exposure on cell growth, tumorigenicity and gene expression in cancer cells

    Yang, Cheng; Li, Yuehui; Zhang, Zhijie; Luo, Chen; Tong, Yongqing; Zhou, Guohua; Xie, Pingli; Hu, Jinyue; Li, Guancheng

    2008-12-01

    It is well recognized that harsh outer space environment, consisting of microgravity and radiation, poses significant health risks for human cells. To investigate potential effects of the space environment exposure on cancer cells we examined the biological changes in Caski cells carried by the "Shen Zhou IV" spaceship. After exposure for 7 days in spaceflight, 1440 survival subclonal cell lines were established and 4 cell lines were screened. 44F10 and 17E3 were selected because of their increased cell proliferation and tumorigenesis, while 48A9 and 31F2 had slower cytological events. Experiments with cell proliferation assay, flow cytometry, soft agar assay, tumorigenesis assay and DNA microarray analysis have shown that selected cell lines presented multiple biological changes in cell morphology, cell growth, tumorigenicity and gene expression. These results suggest that space environment exposure can make significant biological impact on cancer cells and provide an entry point to find the immunological target of tumorigenesis.

  5. In vitro effect on Cryptosporidium parvum of short-term exposure to cathelicidin peptides.

    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

  6. The effects of children's exposure to domestic violence: a meta-analysis and critique.

    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

  7. Effect on Hyalella azteca after pulse exposure to environmentally realistic concentrations of permethrin

    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...

  8. The Lunar Environment: Determining the Health Effects of Exposure to Moon Dusts

    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.

  9. Toxic effects of prenatal exposure to alcohol, tobacco and other drugs.

    Scott-Goodwin, A C; Puerto, M; Moreno, I

    2016-06-01

    Tobacco, alcohol, cannabis and cocaine are the most consumed psychoactive drugs throughout the population. Prenatal exposure to these drugs could alter normal foetal development and could threaten future welfare. The main changes observed in prenatal exposure to tobacco are caused by nicotine and carbon monoxide, which can impede nutrient and oxygen exchange between mother and foetus, restricting foetal growth. Memory, learning processes, hearing and behaviour can also be affected. Alcohol may cause physical and cognitive alterations in prenatally exposed infants, fundamentally caused by altered NMDAR and GABAR activity. Tetrahydrocannabinol, the psychoactive compound of cannabis, is capable of activating CB1R, inducing connectivity deficits during the foetal brain development. This fact could be linked to behavioural and cognitive deficits. Many of the effects from prenatal cocaine exposure are caused by altered cell proliferation, migration, differentiation and dendritic growth processes. Cocaine causes long term behavioural and cognitive alterations and also affects the uteroplacental unit. PMID:27037188

  10. Effect of hot-humid exposure on static strength of adhesive-bonded aluminum alloys

    Rui Zheng

    2015-09-01

    Full Text Available The effect of hot-humid exposure (i.e., 40 °C and 98% R.H. on the quasi-static strength of the adhesive-bonded aluminum alloys was studied. Test results show that the hot-humid exposure leads to the significant decrease in the joint strength and the change of the failure mode from a mixed cohesive and adhesive failure with cohesive failure being dominant to adhesive failure being dominant. Careful analyses of the results reveal that the physical bond is likely responsible for the bond adhesion between L adhesive and aluminum substrates. The reduction in joint strength and the change of the failure mode resulted from the degradation in bond adhesion, which was primarily attributed to the corrosion of aluminum substrate. In addition, the elevated temperature exposure significantly accelerated the corrosion reaction of aluminum, which accelerated the degradation in joint strength.

  11. Effect of UV exposure on photochromic glasses doped with transition metal oxides

    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.

  12. Effects of grain dust exposure and smoking on respiratory symptoms and lung function.

    Cotton, D J; Graham, B L; Li, K Y; Froh, F; Barnett, G D; Dosman, J A

    1983-02-01

    In four groups of individually-matched subjects (nonsmoking grain workers, smoking grain workers, nonsmoking community controls, and smoking community controls) we measured pulmonary function variables from the spirogram, from the maximal expiratory flow-volume curve breathing air and helium, and from the single breath nitrogen test as well as symptom prevalences from a questionnaire in order to assess the relative effects of smoking and occupational exposure to grain dust in Saskatchewan country grain elevators. There were similar increased prevalences of respiratory symptoms and reductions in pulmonary function associated with either grain dust exposure or smoking, but the effects of smoking were slightly more pronounced. The combined effects of grain dust and smoking on lung function appeared to be additive except in the least exposed workers (five years or less) where a synergistic effect was observed in tests of peripheral airways dysfunction. PMID:6834161

  13. Air Distribution Effectiveness for Residential Mechanical Ventilation: Simulation and Comparison of Normalized Exposures

    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).

  14. Effects of Exposure to the Sound from Seismic Airguns on Pallid Sturgeon and Paddlefish.

    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

  15. The effect of chronic exposure to tobacco smoke on the antibacterial defenses of the lung.

    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

  16. Seasonal effect on biomarkers of exposure to petroleum hydrocarbons in fish from Kuwait's marine area.

    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

  17. Effects of combined radiofrequency radiation exposure on levels of reactive oxygen species in neuronal cells

    The objective of this study was to investigate the effects of the combined RF radiation (837 MHz CDMA plus 1950 MHz WCDMA) signal on levels of intracellular reactive oxygen species (ROS) in neuronal cells. Exposure of the combined RF signal was conducted at specific absorption rate values of 2 W/kg of CDMA plus 2 W/kg of WCDMA for 2 h. Co-exposure to combined RF radiation with either H2O2 or menadione was also performed. The experimental exposure groups were incubator control, sham-exposed, combined RF radiation-exposed with or without either H2O2 or menadione groups. The intracellular ROS level was measured by flow cytometry using the fluorescent probe dichlorofluorescein diacetate. Intracellular ROS levels were not consistently affected by combined RF radiation exposure alone in a time-dependent manner in U87, PC12 or SH-SY5Y cells. In neuronal cells exposed to combined RF radiation with either H2O2 or menadione, intracellular ROS levels showed no statically significant alteration compared with exposure to menadione or H2O2 alone. These findings indicate that neither combined RF radiation alone nor combined RF radiation with menadione or H2O2 influences the intracellular ROS level in neuronal cells such as U87, PC12 or SH-SY5Y. (author)

  18. Immunotoxic effects of low level ozone exposure suggestive of an inducers in bronchial hyperresponiveness

    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.

  19. Morphological study of the effects of ozone on rat lung. I. Short-term exposure

    Hiroshima, K.; Kohno, T.; Owada, H.; Hayashi, Y.

    1987-12-01

    In order to determine the effects of ozone on lungs and the course of cell renewal after damage, young male rats were exposed to 3 ppm of ozone for 4 hr. They were killed at 1, 6, 12, and 18 hr and 1, 2, 3, 4, 7, and 14 days after exposure. One hour before the killing, dividing cells were labeled with tritiated thymidine. Type 1 cells of centriacinar location and bronchiolar cells were severely damaged after exposure. Labeling indices of type 2 cells and bronchiolar nonciliated cells increased 1 day after exposure. Hyperplasia of type 2 cells and bronchiolar nonciliated cells was observed 2 and 3 days after exposure. Ciligenesis of bronchiolar ciliated cells occurred 4 days after exposure. Our study shows that injured type 1 cells are repaired by proliferation of type 2 cells and that injured bronchiolar ciliated and Clara cells are repaired by proliferation of bronchiolar nonciliated cells. These undifferentiated cells are probably progenitors of ciliated cells and Clara cells, and some nonciliated cells are in a transitional form between nonciliated and type 2 cells.

  20. Morphological study of the effects of ozone on rat lung. I. Short-term exposure

    In order to determine the effects of ozone on lungs and the course of cell renewal after damage, young male rats were exposed to 3 ppm of ozone for 4 hr. They were killed at 1, 6, 12, and 18 hr and 1, 2, 3, 4, 7, and 14 days after exposure. One hour before the killing, dividing cells were labeled with tritiated thymidine. Type 1 cells of centriacinar location and bronchiolar cells were severely damaged after exposure. Labeling indices of type 2 cells and bronchiolar nonciliated cells increased 1 day after exposure. Hyperplasia of type 2 cells and bronchiolar nonciliated cells was observed 2 and 3 days after exposure. Ciligenesis of bronchiolar ciliated cells occurred 4 days after exposure. Our study shows that injured type 1 cells are repaired by proliferation of type 2 cells and that injured bronchiolar ciliated and Clara cells are repaired by proliferation of bronchiolar nonciliated cells. These undifferentiated cells are probably progenitors of ciliated cells and Clara cells, and some nonciliated cells are in a transitional form between nonciliated and type 2 cells

  1. Effects of repeated short-term cold exposures on cold induced thermogenesis of women

    Silami-Garcia, E.; Haymes, E. M.

    1989-12-01

    The effects of repeated exposures to resting cold air (10°C) on the shivering and thermogenic responses of women to standard cold stress were investigated. Ten women, aged 18 to 34 years, were divided into two groups of five women each. One group, the acclimated (A) was exposed ten times within 2 weeks, the first and the last exposures being the pre-and post-tests respectively. The second group, the control (C) was exposed twice within 18 days. Measurements of rectal and skin temperatures, oxygen uptake, time to onset of shivering (TOS), and perceived cold were performed during all exposures. Shivering responses were evaluated by electromyography and visually. A significant ( P<0.05), increase was seen in TOS (from 26.2 min to 55.6 min), and a significant decrease was seen in thermoregulatory heat production (from 14.78 kcal/h to -2.64 kcal/h) in group A; these changes were evident after about five exposures. It is concluded that the women became cold acclimated as a result of the repeated short-term resting cold air exposures.

  2. The Alberta Oil Sands Community Exposure and Health Effects Assessment Program : methods report

    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 (SO2), nitrogen dioxide (NO2), ozone (O3) 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

  3. The effects of repeated exposure to graphic fear appeals on cigarette packages: A field experiment.

    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

  4. Ratios between effective doses for tomographic and mathematician models due to internal exposure of photons

    The development of new and sophisticated Monte Carlo codes and tomographic human phantoms or voxels motivated the International Commission on Radiological Protection (ICRP) to revise the traditional models of exposure, which have been used to calculate effective dose coefficients for organs and tissues based on mathematician phantoms known as MIRD5. This paper shows the results of calculations using tomographic phantoms MAX (Male Adult voXel) and FAX (Female Adult voXel), recently developed by the authors as well as with the phantoms ADAM and EVA, of specific genres, type MIRD5, coupled to the EGS4 Monte Carlo and MCNP4C codes, for internal exposure with photons of energies between 10 keV and 4 MeV to several organs sources. Effective Doses for both models, tomographic and mathematician, will be compared separately as a function of the Monte Carlo code replacement, of compositions of human tissues and the anatomy reproduced through tomographs. The results indicate that for photon internal exposure, the use of models of exposure based in voxel, increases the values of effective doses up to 70% for some organs sources considered in this study, when compared with the corresponding results obtained with phantoms of MIRD-5 type

  5. Effects of U46619 on human platelets: dissociation of shape change from fibrinogen receptor exposure

    In the present study the authors measured the specific effects of U46619 (15(s)-hydroxy-9α,11α-methano-epoxy-prostadienoic acid), a TxA2/PGH2 analog on platelet (plt) activation. Plt shape change (SC) myosin light chain phosphorylation (MLC-P) and fg receptor exposure (using I125fg), were measured. SC, and MLC-P were saturable and dose dependent. EC50 values are as follows: SC;61.3nM +/- 32nM(n=10), MLC-P;0.15μM. Interaction of U46619 with a specific membrane receptor was inferred from studies using BM13177, (2-benzene-sulphonamido)-ethyl)-phenoxyacetic acid) a specific TxA2/PGH2 antagonist. The IC50 of BM13177 for MLC-P, was 6.5μM and for SC was 4.3μM. Concentrations of U46619 (50-200nM) that gave MLC-P and SC similar to ADP (5-10μM) caused minimal exposure of fg receptors (302 sites/plt) and no plt aggregation when 400μg/mL fg was added to the system. In contrast, ADP caused SC, fg receptor exposure (8000 sites/plt) and aggregation. Higher concentrations of U46619 (0.2-1μM) caused SC, exposure of fg receptors (19,000 sites/plt) and when fg was added, aggregation. But the receptor exposure and aggregation responses by U46619 were blocked by addition of the ADP scavenger, apyrase. In conclusion, U46619 causes the following direct effects in human plts: MLC-P, and SC; and through released ADP, exposure of fg receptors

  6. PSYCHOBIOLOGICAL EFFECTS OF PRENATAL GLUCOCORTCOID EXPOSURE IN 10-YEAR-OLD-CHILDREN

    UlrikeEhlert; RolandZimmermann

    2012-01-01

    Background: Prenatal stress seems to have long-lasting effects on biological and psychological processes of the offspring. However, to date, there have been no studies investigating the effects of prenatal glucocorticoid exposure on psychological, endocrine, and autonomic responses to a standardized psychosocial stress test in children. Methods: A sample of 115 healthy, ten-year-old children was examined. The Glucocorticoids+Tocolytics group was characterized by tocolytic treatment of the ...

  7. Effects of prenatal exposure to xylene on postnatal development and behavior in rats

    Hass, Ulla; Lund, S. P.; Simonsen, L.; Fries, A. S.

    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...... maze) were found. Generally, the effects were most marked in the female offspring....

  8. Effect of Prenatal Exposure to Lead on Estrogen Action in the Prepubertal Rat Uterus

    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...

  9. Childhood Violence Exposure: Cumulative and Specific Effects on Adult Mental Health

    Hooven, Carole; Nurius, Paula S.; Logan-Greene, Patricia; Thompson, Elaine A.

    2012-01-01

    Childhood exposure to violence and victimization is a significant public health problem, with potentially long-lasting, deleterious effects on adult mental health. Using a longitudinal study design, 123 young adults—identified in adolescence as at-risk for high school dropout—were examined for the effects of multi-domain childhood victimization on emotional distress and suicide risk, net of adolescent risk and protective factors, including family dysfunction. The hypothesis that higher levels...

  10. Sensorineural Hearing Loss Associated with Occupational Noise Exposure: Effects of Age-Corrections

    Krishnamurti, Sridhar

    2009-01-01

    Noise-induced permanent threshold shifts (NIPTS) were computed from retrospective audiometric analyses by subtracting aging effects on hearing sensitivity in sixty-eight patients with bilateral sensorineural hearing loss who reported significant occupational noise exposure histories. There were significant effects of age on NIPTS but no significant gender- or ear- differences in terms of NIPTS. The NIPTS at 2,000 Hz was found to be significantly greater than NIPTS at frequencies 500 Hz, 1,000...

  11. Effect of regular aerobic exercise with ozone exposure on peripheral leukocyte populations in Wistar male rats

    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...

    • Transgenerational Effects of Stress Exposure on Offspring Phenotypes in Apomictic Dandelion

      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 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 o...

    • Prenatal cocaine exposure alters emotional arousal regulation and its effects on working memory

      Li, Zhihao; Coles, Claire D.; Lynch, Mary Ellen; Hamann, Stephan; Peltier, Scott; LaConte, Stephen; Hu, Xiaoping

      2009-01-01

      While prenatal cocaine exposure (PCE) has been associated with arousal dysregulation and attentional impairments in both human and animal studies, the neurobiological bases of these teratogenic effects have not been well characterized. In the current study, we report functional neuroimaging observations of these effects in exposed youth. Using functional magnetic resonance imaging (fMRI), we embedded task-irrelevant emotional distracters in a working memory task to examine the interaction of ...

    • Individual differences in the effects of prenatal stress exposure in rodents

      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...

    • Effects of pyrene exposure and temperature on early development of two co-existing Arctic copepods

      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...... 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...

    • Effect of exposure to radiation on the inflammatory process and its influence by diclofenac.

      el-Ghazaly, M.; Kenawy, S.; Khayyal, M T; Roushdy, H.; Saleh, S.

      1985-01-01

      The effect of radiation exposure on the inflammatory process was studied in rats using the carrageenan-induced paw oedema and adjuvant-induced arthritis tests. Irradiation (0.5,1 and 2 Grays) resulted in a significant augmentation of the tissue response to carrageenan and the early phase of adjuvant-induced arthritis, but suppressed the late phase. Diclofenac (1-5 mg kg-1) effectively reduced the exaggerated inflammatory response in irradiated animals in both the carrageenan paw oedema and ad...

    • Effects of combined exposure of rats to 239PuO2 and whole-body X irradiation. II

      Using F344/N rats, we are studying the biological effects of inhalation exposure to 239PuO2 aerosols combined with whole-body exposure to X rays. Data from this study will provide an improved estimate of the cancer risk from combined exposures in people. A total of 2136 (66%) of the 3232 rats to be entered into this study have been exposed. We have achieved lung burdens of 239Pu and X-ray exposures within the ranges desired. Life shortening has occurred among rats receiving whole-body exposure to X rays, but not among those exposed only to 239PuO2. (author)

    • Risk of Adverse Health and Performance Effects of Celestial Dust Exposure

      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 Prenatal Tobacco, Alcohol and Marijuana Exposure on Processing Speed, Visual-Motor Coordination, and Interhemispheric Transfer

      Willford, Jennifer A.; Chandler, Lynette S.; Goldschmidt, Lidush; Day, Nancy L.

      2010-01-01

      Deficits in motor control are often reported in children with prenatal alcohol exposure (PAE). Less is known about the effects of prenatal tobacco exposure (PTE) and prenatal marijuana exposure (PME) on motor coordination, and previous studies have not considered whether PTE, PAE, and PME interact to affect motor control. This study investigated the effects of PTE, PAE, and PME as well as current drug use on speed of processing, visual-motor coordination, and interhemispheric transfer in 16-y...

    • Effects of Neonatal Methamphetamine and Thioperamide Exposure on Spatial Memory Retention and Circadian Activity Later in Life

      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 ...

  1. Effect of repeated benzene inhalation exposures on benzene metabolism, binding to hemoglobin, and induction of micronuclei

    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

  2. Effect of regular aerobic exercise with ozone exposure on peripheral leukocyte populations in Wistar male rats

    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.

  3. UV radiation: sources, effects and risks of human and environmental exposure

    This paper summarizes the principal results of a review study on UV- -exposure and UV related risks in the Netherlands. Both the present state of affairs and future developments are discussed, the latter partly based on model calculations. The sun is the main UV source to which the whole population is exposed. Solar exposure is estimated to amount at least 90% of the annual UV burden for the Dutch population. For certain groups in the population man made sources are estimated to contribute considerably to the yearly UV dose. Ozone depletion as a result of human activities, growing use of tungsten halogen lamps and increasing application of UV-sources in industry and medicine all tend to increase UV exposure. UV exposure can lead to a wide variety of health effects, among which the induction of skin cancer, skin aging, cataract formation and suppression of immune responses. Risk estimates of these health effects are available for skin cancer and to a lesser extend for cataracts. The estimated UV related skin cancer incidence rate in the Netherlands is 10-3 per year (15 000 cases), and the associated mortality rate amounts to 6-25·10-6 per year (90-400 deaths). The ozone depletion presently observed over the past decade (5% in the Netherlands), is expected to lead to an increased annual mortality rate due to skin cancer of 1,3·10-6 per year. Environmental exposure can influence plant physiology and lead to a decrease of biomass in aquatic as well as terrestrial ecosystems. This may result in adverse effects on the foodweb and biodiversity of ecosystems. Quantitative risk estimates for these effects are very uncertain or lacking. (author)

  4. The delayed effects of radiation exposure among atomic bomb survivors, Hiroshima and Nagasaki, 1945-79

    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)

  5. Sensorineural Hearing Loss Associated with Occupational Noise Exposure: Effects of Age-Corrections

    2009-02-01

    Full Text Available Noise-induced permanent threshold shifts (NIPTS were computed from retrospective audiometric analyses by subtracting aging effects on hearing sensitivity in sixty-eight patients with bilateral sensorineural hearing loss who reported significant occupational noise exposure histories. There were significant effects of age on NIPTS but no significant gender- or ear- differences in terms of NIPTS. The NIPTS at 2,000 Hz was found to be significantly greater than NIPTS at frequencies 500 Hz, 1,000 Hz, 4,000 Hz, and 8,000 Hz. Defined noise notches were seen in the audiograms of 38/136 (27% ears with SNHL. Results support models that suggest interactive effects of aging and noise on sensorineural hearing loss in ears with occupational noise exposure.

  6. The effect of ultralow-dose antibiotics exposure on soil nitrate and N2O flux

    Devries, Stephanie L.; Loving, Madeline; Li, Xiqing; Zhang, Pengfei

    2015-11-01

    Exposure to sub-inhibitory concentrations of antibiotics has been shown to alter the metabolic activity of micro-organisms, but the impact on soil denitrification and N2O production has rarely been reported. In this study, incubation and column transport experiments were conducted on soils exposed to as many as four antibiotics in the ng·kg-1 range (several orders of magnitude below typical exposure rates) to evaluate the impact of ultralow dose exposure on net nitrate losses and soil N2O flux over time. Under anaerobic incubation conditions, three antibiotics produced statistically significant dose response curves in which denitrification was stimulated at some doses and inhibited at others. Sulfamethoxazole in particular had a stimulatory effect at ultralow doses, an effect also evidenced by a near 17% increase in nitrate removal during column transport. Narasin also showed evidence of stimulating denitrification in anaerobic soils within 3 days of exposure, which is concurrent to a statistically significant increase in N2O flux measured over moist soils exposed to similar doses. The observation that even ultralow levels of residual antibiotics may significantly alter the biogeochemical cycle of nitrogen in soil raises a number of concerns pertaining to agriculture, management of nitrogen pollution, and climate change, and warrants additional investigations.

  7. The Effects of Technology Innovativeness and System Exposure on Student Acceptance of E-textbooks

    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.

  8. Effects of diethylstilbestrol exposure during gestation on both maternal and offspring behavior.

    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.

  9. Mechanical counter pressure on the arm counteracts adverse effects of hypobaric exposures

    Tanaka, Kunihiko; Limberg, Ryan; Webb, Paul; Reddig, Mike; Jarvis, Christine W.; Hargens, Alan R.

    2003-01-01

    INTRODUCTION: Current space suits have limited movement due to gas pressurization during exposure to the vacuum of space. Alternatively, if pressure is applied by an elastic garment vs. pneumatic garment to produce mechanical counter pressure (MCP), several advantages are possible. In this study, we investigate local microcirculatory and other effects produced with and without a prototype MCP glove and sleeve during exposure to varying levels of vacuum. METHODS: The entire arms of eight male volunteers were studied at normal ambient pressure and during 5 min exposures to -50, -100, and -150 mm Hg with and without the MCP glove and sleeve. Pressure distribution, skin microvascular flow, and temperature were measured. RESULTS: The MCP glove and sleeve generated over 200 mm Hg on the middle finger, dorsum of the hand, and the wrist. However, pressure was significantly lower on the forearm and the upper arm. Without the glove and sleeve, only two of eight subjects tolerated -100 mm Hg. Also, no subject tolerated -150 mm Hg. However, subjects tolerated all vacuum pressures wearing the glove and sleeve. Skin microvascular flow and temperature remained within control values with the glove and sleeve at a chamber pressure of -150 mm Hg. DISCUSSION: The MCP glove and sleeve counteracts adverse effects of vacuum exposures due to lower pressure differentials. Pressure levels over the hand and wrist are similar to those of the current U.S. space suit glove and sleeve, but additional development is required to increase MCP over the forearm and upper arm.

  10. Delayed emergence of behavioral and electrophysiological effects following juvenile ketamine exposure in mice.

    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

  11. Prenatal Exposures to Multiple Thyroid Hormone Disruptors: Effects on Glucose and Lipid Metabolism.

    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

  12. Biological and sanitary effects of non ionizing radiations

    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.)

  13. Effects of Perinatal Exposure to PCBs on Neuropsychological Functions in the Rotterdam Cohort at 9 Years of Age

    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

  14. Combined effect of radon exposure and smoking and their interaction in Czech studies of lung cancer

    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)

  15. Effect of Second-Hand Smoke Exposure on Lung Function among Non-Smoking Korean Women.

    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.

  16. Effect of acute ozone exposure on the proteinase-antiproteinase balance in the rat lung

    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

  17. Effects of titanium dioxide nanoparticle exposure in Mytilus galloprovincialis gills and digestive gland.

    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

  18. 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

    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.

  19. EFFECTS OF TRITIUM EXPOSURE ON UHMW-PE, PTFE, AND VESPEL

    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

  20. The effects of in utero bisphenol A exposure on reproductive capacity in several generations of mice

    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

  1. The effects of in utero bisphenol A exposure on reproductive capacity in several generations of mice

    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.

  2. An examination of direct and indirect effects of exposure and attention to health media on intentions to avoid unprotected sun exposure.

    Lovejoy, Jennette; Riffe, Daniel; Lovejoy, Travis I

    2015-01-01

    Skin cancer is the most commonly diagnosed cancer in the United States, accounting for more than 2 million diagnoses and more than 9,000 deaths annually. A regional online survey of students enrolled at institutions of higher education (N = 1,251) examined (a) associations between health media use and intentions to avoid unprotected sun exposure and (b) theoretically derived health behavior constructs that may mediate the relationship between media use and individuals' decisions to avoid unprotected sun exposure. Individuals with greater exposure and attention to health information in television, magazines, and newspapers had higher intentions to avoid unprotected sun exposure. Multiple mediation models indicated that health behavior constructs collectively mediated the relationship between television use and sun-protective behavioral intentions. Both cumulative and specific indirect mediating effects were observed for the relationship between magazine use and sun-protective behavioral intentions. However, the direction of effects was opposite to the hypothesized direction, due primarily to the association of magazine use with less favorable attitudes about sun protection and reduced behavioral control to avoid unprotected sun exposure. This study provides preliminary evidence for the interrelationships among media use, internal psychological states and cognitions, and health behavior decision making. Future studies should further explicate the mediating processes that account for the relationships between media and health behavior. PMID:24597527

  3. Sublethal effects of multiwalled carbon nanotube exposure in the invertebrate Daphnia magna.

    Stanley, Jacob K; Laird, Jennifer G; Kennedy, Alan J; Steevens, Jeffery A

    2016-01-01

    Carbon nanotubes were previously demonstrated to accumulate on the carapace and in the gut of daphnids in aquatic exposures. The purpose of the present study was to assess the effects of multiwalled carbon nanotube (MWCNT) exposure on the sublethal Daphnia magna endpoints swimming behavior, algal feeding, growth, and reproduction and to determine the relative magnitude of difference between lethal and sublethal toxicity thresholds in 48-h and 14-d exposures. A stable dispersion of MWCNTs was prepared using 100 mg/L natural organic matter (NOM), and all treatments were compared statistically to a NOM control. The swimming behavior endpoints of mean velocity and total distance moved were determined using digital tracking software. For the acute (48-h) exposure, a 50% lethal concentration (LC50) of 29.3 (23.6-36.3) mg/L and a 50% effective concentration (EC50) of 6.7 mg/L in the swimming velocity endpoint were determined. When swimming response was nonmonotonic below 2 mg/L, consistent reductions in velocity were observed at 6.9 mg/L and above. Median effect concentrations were lower in the chronic (14-d) bioassay. The 14-d LC50 was 4.3 mg/L (3.3-5.6 mg/L), and the reproduction EC50 was 5.0 mg/L. Lowest-observed-effect concentrations for survival and reproduction were 5.4 mg/L and 1.7 mg/L, respectively. Significantly fewer (23.1%) algal cells were consumed in the 3.9-mg/L treatment relative to the control. No significant effects on swimming behavior were observed for the 14-d bioassay. Less traditional sublethal endpoints such as swimming behavior and feeding rate may be especially important to assess for MWCNTs and other materials expected to be more physically than chemically toxic through mechanisms such as gut clogging. PMID:26222333

  4. Developmental effects of barium exposure in a marine bivalve (Mytilus californianus)

    Produced water, an aqueous waste of variable composition associated with petroleum and natural gas extraction, is frequently discharged into the marine environment in significant quantities. Concern and controversy exist regarding potential adverse environmental effects related to such discharges. Previous reports indicated that barium (Ba) and/or strontium (Sr) were primarily responsible for the toxicity of a southern California produced water to developing marine embryos. To further investigate toxicity of Ba and Sr in seawater, mussel embryos (Mytilus californianus) were subjected to static exposures of barium acetate and strontium chloride from fertilization through veliger formation. Only Ba exhibited bioactivity at environmentally relevant levels. Adverse effects occurred between 200 and 900 microg/L (ppb); higher concentrations were associated with decreased toxicity and apparent precipitation of Ba salts from seawater. Nominal Ba exposure concentrations between 100 and 900 microg/L yielded measured concentrations of 100 to 550 microg/L soluble Ba when analyzed by inductively coupled argon plasma emission spectroscopy. Adverse developmental effects included abnormal shell calcification and embryo morphology. Exposure of embryos to Ba in state-specific experiments revealed that developmental stages were differentially affected, though they exhibited similar abnormalities. Gastrulae were the most sensitive, while blastula and trochophore larvae were less so. Adverse effects in embryos exposed during the gastrula stage were not reversible despite washing and return to clean seawater. These findings are among the first to demonstrate that low concentrations of soluble Ba in seawater can be toxic and are of potential concern in the marine environment

  5. STUDIES CONCERNING THE EFFECT OF GAMMA RADIATION AND MAGNETIC FIELD EXPOSURE ON GLADIOLUS

    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.

  6. Some Behavioral Effects of Exposure to Low Doses of Fe-56 Particles

    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.

  7. Effects of sodium pentaborate pentahydrate exposure on Chlorella vulgaris growth, chlorophyll content, and enzyme activities.

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

    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.

  9. Effects of benzophenone-3 exposure on endocrine disruption and reproduction of Japanese medaka (Oryzias latipes)—A two generation exposure study

    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

  10. Effects of benzophenone-3 exposure on endocrine disruption and reproduction of Japanese medaka (Oryzias latipes)—A two generation exposure study

    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

  11. Interactive effects of maternal and environmental exposure to coal combustion wastes decrease survival of larval southern toads (Bufo terrestris)

    We conducted a mesocosm study to assess the individual and interactive effects of previous maternal exposure and larval exposure to trace element-laden sediments on southern toads (Bufo terrestris). Previous maternal exposure to coal combustion wastes (CCW) reduced larval survival to metamorphosis up to 57% compared to larvae of unexposed females. Larvae reared on CCW accumulated significant concentrations of trace elements resulting in extended larval periods, reduced growth rates, and reduced mass at metamorphosis. However, the effects were dependent on age of sediments, suggesting the effects of contaminants from CCW may be partially ameliorated over time through the reduced bioavailability of trace elements in aged CCW. Most importantly, maternal exposure to contaminants coupled with larval exposure to fresh CCW interacted to reduce survival to metamorphosis by 85% compared to reference conditions. Our study yields further evidence that disposal of CCW in aquatic basins potentially creates ecological traps for some amphibian populations. - Highlights: ► The interaction of maternal exposure and larval exposure to CCW reduced survival. ► Previous maternal exposure to CCW had a latent effect on survival to metamorphosis. ► Larval southern toads exposed to CCW experienced prolonged larval periods. ► Larval southern toads exposed to CCW had reduced growth rates. ► Larval southern toads exposed to CCW had reduced mass at metamorphosis. - Maternal and environmental exposure to coal combustion wastes interact to decrease survival in larval amphibians.

  12. Fetotoxic effects of exposure to the vapor of organic solvents from a synthetic adhesive in mice

    Tachi, N.; Shimotori, S.; Naruse, N.; Itani, T.; Aoyama, M. (Nagoya City Univ. Medical School (Japan)); Fujise, H.; Sonoki, S. (Azabu Univ., Kanagawa (Japan))

    1994-09-01

    Synthetic adhesives are widely used in various industries as well as at home. Adhesives usually contain several organic solvents which easily vaporize. Exposure can cause aplastic anemia and polyneuropathy in adults. Chronic glue sniffing results in aplastic anemia, polyneuropathy, and muscular atrophy. Inhalation of the solvent contained in adhesives, such as n-hexane, toluene, xylene, and benzene by pregnant animals can decrease the number of live fetuses and retard fetal growth. In humans, the risk of spontaneous abortion is increased in workers exposed to organic solvents. However, information is still limited about the effects of exposure to organic solvents vaporized from adhesives on fetuses. In the present study, female mice were exposed throughout pregnancy to organic solvents vaporized from an adhesive to clarify the effects of the inhalation on progeny. 19 refs., 1 fig., 4 tabs.

  13. Cellular effects and gene expression after exposure to amorphous silica nanoparticles in vitro

    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...

  14. Effect of Temperature Cycling and Exposure to Extreme Temperatures on Reliability of Solid Tantalum Capacitors

    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.

  15. Effects of Pesticide Exposure on Embryonic Development and Hatchling Traits of Turtles

    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.

  16. Effects of ambient air particulate exposure on blood-gas barrier permeability and lung function

    Bräuner, Elvira Vaclavik; Mortensen, Jann; Møller, Peter;

    2009-01-01

    Particulate air pollution is associated with increased risk of pulmonary diseases and detrimental outcomes related to the cardiovascular system, including altered vessel functions. This study's objective was too evaluate the effects of ambient particle exposure on the blood-gas permeability, lung...... effect on the concentration of CC16 in plasma and urine or on the static and dynamic volumes or ventilation distribution of the lungs. The study thus demonstrates increased permeability of the alveolar blood-gas barrier following moderate exercise, whereas exposure to ambient levels of urban air.......5-15.8 microg/m(3) PM(10-2.5)) or filtered (91-542 particles/cm(3)) air collected above a busy street. The clearance rate of aerosolized (99m)Tc-labeled diethylenetriamine pentaacetic acid ((99m)Tc-DTPA) was measured as an index for the alveolar epithelial membrane integrity and permeability of the lung blood...

  17. Effects of Copper Exposure on Photosynthesis and Growth of the Seagrass Cymodocea nodosa: An Experimental Assessment.

    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

  18. Phytotoxic and genotoxic effects of silver nanoparticles exposure on germinating wheat seedlings.

    Vannini, Candida; Domingo, Guido; Onelli, Elisabetta; De Mattia, Fabrizio; Bruni, Ilaria; Marsoni, Milena; Bracale, Marcella

    2014-08-15

    We investigated the effects of 1 and 10 mg L(-1) AgNPs on germinating Triticum aestivum L. seedlings. The exposure to 10 mg L(-1) AgNPs adversely affected the seedling growth and induced morphological modifications in root tip cells. TEM analysis suggests that the observed effects were due primarily to the release of Ag ions from AgNPs. To gain an increased understanding of the molecular response to AgNP exposure, we analyzed the genomic and proteomic changes induced by AgNPs in wheat seedlings. At the DNA level, we applied the AFLP technique and we found that both treatments did not induce any significant DNA polymorphisms. 2DE profiling of roots and shoots treated with 10 mg L(-1) of AgNPs revealed an altered expression of several proteins mainly involved in primary metabolism and cell defense. PMID:24973586

  19. Radiation exposure effects on the performance of an electrically trainable artificial neural network (ETANN)

    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

  20. Health Status and Residential Exposure to Air Toxics: What Are the Effects on Children's Academic Achievement?

    Clark-Reyna, Stephanie E; Grineski, Sara E; Collins, Timothy W

    2016-01-01

    This article examines the effects of children's subjective health status and exposure to residential environmental toxins on academic performance for the first time, while adjusting for school-level effects using generalized estimating equations. The analysis employs National Air Toxics Assessment risk estimates and individual-level data collected through a mail survey. Results indicate that poorer subjective health status and higher levels of residential air toxins are statistically significantly associated with lower grade point averages, meaning that there is an independent effect of air pollution on children's academic achievement that cannot be explained by poor health alone. PMID:27214671