WorldWideScience

Sample records for sound exposure levels

  1. On the assessment of shooting sounds : Loudness-level weightings versus A- and C-weighted sound exposure levels (L)

    NARCIS (Netherlands)

    Vos, J.; Geurtsen, F.W.M.

    2003-01-01

    As an alternative to the A-weighted sound exposure level (ASEL) Schomer et al. [J. Acoust. Soc. Am. 110, 2390-2397 (2001)] used the equal-loudness level contours as a dynamic filter to determine the loudness-level-weighted sound exposure level (LLSEL). From their analyses they concluded that the

  2. Common sole larvae survive high levels of pile-driving sound in controlled exposure experiments.

    Directory of Open Access Journals (Sweden)

    Loes J Bolle

    Full Text Available In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at which (sub-lethal effects occur is limited for juvenile and adult fish, and virtually non-existent for fish eggs and larvae. A device was developed in which fish larvae can be exposed to underwater sound. It consists of a rigid-walled cylindrical chamber driven by an electro-dynamical sound projector. Samples of up to 100 larvae can be exposed simultaneously to a homogeneously distributed sound pressure and particle velocity field. Recorded pile-driving sounds could be reproduced accurately in the frequency range between 50 and 1000 Hz, at zero to peak pressure levels up to 210 dB re 1µPa(2 (zero to peak pressures up to 32 kPa and single pulse sound exposure levels up to 186 dB re 1µPa(2s. The device was used to examine lethal effects of sound exposure in common sole (Solea solea larvae. Different developmental stages were exposed to various levels and durations of pile-driving sound. The highest cumulative sound exposure level applied was 206 dB re 1µPa(2s, which corresponds to 100 strikes at a distance of 100 m from a typical North Sea pile-driving site. The results showed no statistically significant differences in mortality between exposure and control groups at sound exposure levels which were well above the US interim criteria for non-auditory tissue damage in fish. Although our findings cannot be extrapolated to fish larvae in general, as interspecific differences in vulnerability to sound exposure may occur, they do indicate that previous assumptions and criteria may need to be revised.

  3. Geluidsexpositie bij Gebruik van Otoplastieken met Communicatie (Sound Exposure Level of F-16 Crew Chiefs Using Custom Molded Communications Earplugs)

    National Research Council Canada - National Science Library

    Houben, M. M; Verhave, J. A

    2008-01-01

    .... In a previous study, we developed a method to assess the sound exposure level of CEP users. Not only was the attenuated F 16 noise taken into account, but also the sound exposure resulting from communication through the CEP...

  4. Chronic scream sound exposure alters memory and monoamine levels in female rat brain.

    Science.gov (United States)

    Hu, Lili; Zhao, Xiaoge; Yang, Juan; Wang, Lumin; Yang, Yang; Song, Tusheng; Huang, Chen

    2014-10-01

    Chronic scream sound alters the cognitive performance of male rats and their brain monoamine levels, these stress-induced alterations are sexually dimorphic. To determine the effects of sound stress on female rats, we examined their serum corticosterone levels and their adrenal, splenic, and thymic weights, their cognitive performance and the levels of monoamine neurotransmitters and their metabolites in the brain. Adult female Sprague-Dawley rats, with and without exposure to scream sound (4h/day for 21 day) were tested for spatial learning and memory using a Morris water maze. Stress decreased serum corticosterone levels, as well as splenic and adrenal weight. It also impaired spatial memory but did not affect the learning ability. Monoamines and metabolites were measured in the prefrontal cortex (PFC), striatum, hypothalamus, and hippocampus. The dopamine (DA) levels in the PFC decreased but the homovanillic acid/DA ratio increased. The decreased DA and the increased 5-hydroxyindoleacetic acid (5-HIAA) levels were observed in the striatum. Only the 5-HIAA level increased in the hypothalamus. In the hippocampus, stress did not affect the levels of monoamines and metabolites. The results suggest that scream sound stress influences most physiologic parameters, memory, and the levels of monoamine neurotransmitter and their metabolites in female rats. Copyright © 2014. Published by Elsevier Inc.

  5. Temporary threshold shifts from exposures to equal equivalent continuous A-weighted sound pressure level

    DEFF Research Database (Denmark)

    Ordoñez, Rodrigo Pizarro; Hammershøi, Dorte

    2014-01-01

    the assumptions made using the A-weighting curve for the assessment of hearing damage. By modifying exposure ratings to compensate for the build-up of energy at mid and high-frequencies (above 1 kHz) due to the presence of the listener in the sound field and for the levels below an effect threshold that does...... not induce changes in hearing (equivalent quiet levels), ratings of the sound exposure that reflect the observed temporary changes in auditory function can be obtained.......According to existing methods for the assessment of hearing damage, signals with the same A-weighted equivalent level should pose the same hazard to the auditory system. As a measure of hazard, it is assumed that Temporary Thresholds Shifts (TTS) reflect the onset of alterations to the hearing...

  6. An analysis of collegiate band directors' exposure to sound pressure levels

    Science.gov (United States)

    Roebuck, Nikole Moore

    Noise-induced hearing loss (NIHL) is a significant but unfortunate common occupational hazard. The purpose of the current study was to measure the magnitude of sound pressure levels generated within a collegiate band room and determine if those sound pressure levels are of a magnitude that exceeds the policy standards and recommendations of the Occupational Safety and Health Administration (OSHA), and the National Institute of Occupational Safety and Health (NIOSH). In addition, reverberation times were measured and analyzed in order to determine the appropriateness of acoustical conditions for the band rehearsal environment. Sound pressure measurements were taken from the rehearsal of seven collegiate marching bands. Single sample t test were conducted to compare the sound pressure levels of all bands to the noise exposure standards of OSHA and NIOSH. Multiple regression analysis were conducted and analyzed in order to determine the effect of the band room's conditions on the sound pressure levels and reverberation times. Time weighted averages (TWA), noise percentage doses, and peak levels were also collected. The mean Leq for all band directors was 90.5 dBA. The total accumulated noise percentage dose for all band directors was 77.6% of the maximum allowable daily noise dose under the OSHA standard. The total calculated TWA for all band directors was 88.2% of the maximum allowable daily noise dose under the OSHA standard. The total accumulated noise percentage dose for all band directors was 152.1% of the maximum allowable daily noise dose under the NIOSH standards, and the total calculated TWA for all band directors was 93dBA of the maximum allowable daily noise dose under the NIOSH standard. Multiple regression analysis revealed that the room volume, the level of acoustical treatment and the mean room reverberation time predicted 80% of the variance in sound pressure levels in this study.

  7. Common sole larvae survive high levels of pile-driving sound in controlled exposure experiments

    NARCIS (Netherlands)

    Bolle, L.J.; Jong, C.A.F. de; Bierman, S.M.; Beek, P.J.G. van; Keeken, O.A. van; Wessels, P.W.; Damme, C.J.G. van; Winter, H.V.; Haan, D. de; Dekeling, R.P.A.

    2012-01-01

    In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at

  8. Sound Exposure of Symphony Orchestra Musicians

    DEFF Research Database (Denmark)

    Schmidt, Jesper Hvass; Pedersen, Ellen Raben; Juhl, Peter Møller

    2011-01-01

    dBA and their left ear was exposed 4.6 dB more than the right ear. Percussionists were exposed to high sound peaks >115 dBC but less continuous sound exposure was observed in this group. Musicians were exposed up to LAeq8h of 92 dB and a majority of musicians were exposed to sound levels exceeding......Background: Assessment of sound exposure by noise dosimetry can be challenging especially when measuring the exposure of classical orchestra musicians where sound originate from many different instruments. A new measurement method of bilateral sound exposure of classical musicians was developed...... and used to characterize sound exposure of the left and right ear simultaneously in two different symphony orchestras.Objectives: To measure binaural sound exposure of professional classical musicians and to identify possible exposure risk factors of specific musicians.Methods: Sound exposure was measured...

  9. High levels of sound pressure: acoustic reflex thresholds and auditory complaints of workers with noise exposure

    Directory of Open Access Journals (Sweden)

    Alexandre Scalli Mathias Duarte

    2015-08-01

    Full Text Available INTRODUCTION: The clinical evaluation of subjects with occupational noise exposure has been difficult due to the discrepancy between auditory complaints and auditory test results. This study aimed to evaluate the contralateral acoustic reflex thresholds of workers exposed to high levels of noise, and to compare these results to the subjects' auditory complaints.METHODS: This clinical retrospective study evaluated 364 workers between 1998 and 2005; their contralateral acoustic reflexes were compared to auditory complaints, age, and noise exposure time by chi-squared, Fisher's, and Spearman's tests.RESULTS: The workers' age ranged from 18 to 50 years (mean = 39.6, and noise exposure time from one to 38 years (mean = 17.3. We found that 15.1% (55 of the workers had bilateral hearing loss, 38.5% (140 had bilateral tinnitus, 52.8% (192 had abnormal sensitivity to loud sounds, and 47.2% (172 had speech recognition impairment. The variables hearing loss, speech recognition impairment, tinnitus, age group, and noise exposure time did not show relationship with acoustic reflex thresholds; however, all complaints demonstrated a statistically significant relationship with Metz recruitment at 3000 and 4000 Hz bilaterally.CONCLUSION: There was no significance relationship between auditory complaints and acoustic reflexes.

  10. Exposure to classroom sound pressure level among dance teachers in Porto Alegre (RS

    Directory of Open Access Journals (Sweden)

    Nehring, Cristiane

    2013-01-01

    Full Text Available Introduction: Dance teachers are exposed to high sound intensities. Aim: To verify the sound intensity of music used by dance teachers during classes. Method: This was a transversal and prospective study. Dance teachers were evaluated with a sociodemographic questionnaire, and sound intensity level measurements were taken at the beginning, middle, and end of dance classes. Results: The sample comprised 35 teachers (average age, 31.8 years. The duration of their career as dance teachers was 1-37 years; they worked daily for approximately 1-10 h. Among the classes followed, there were 15 (42.85% classical ballet classes, 4 (11.42% tap dancing lessons, 5 (14.28% jazz dance classes, 2 (5.71 Arab dance lessons, 6 (17.14% street dance classes, and 3 (8.57% ballroom dancing lessons. The average values observed at the beginning, middle, and end of the classes were 80.91 dB (A, 83.22 dB (A, and 85.19 dB (A, respectively. The music played in the street dance classes exposed teachers to the highest sound intensity. Conclusion: The average level of sound intensity of the dance classes in this study was either below or equal to the limit considered harmful for hearing health. Analysis of different class types showed that the sound densities of street, ballroom, and tap dance classes were above the recommended limits.

  11. Noise exposure in movie theaters: a preliminary study of sound levels during the showing of 25 films.

    Science.gov (United States)

    Warszawa, Anna; Sataloff, Robert T

    2010-09-01

    The harmful effects of noise exposure during leisure-time activities are beginning to receive some scrutiny. We conducted a preliminary study to investigate the noise levels during the showings of 25 different films. During each screening, various sound measurements were made with a dosimeter. The movies were classified on the basis of both their Motion Picture Association of America (MPAA) rating and their genre, and the size of the theater and the size of the audience were taken into consideration in the final analysis. Our findings suggest that the sound levels of many movies might be harmful to hearing, although we can draw no definitive conclusions. We did not discern any relationship between noise levels and either MPAA rating or genre. Further studies are recommended.

  12. Geluidsexpositie bij Gebruik van Otoplastieken met Communicatie (Sound Exposure Level of F-16 Crew Chiefs Using Custom Molded Communications Earplugs)

    Science.gov (United States)

    2008-10-01

    346 35 39 77 lnfo-DenV@tno nl Datum oktober 2008 Auteur (s) dr. ir. MM..I. Houben J.A. Verhave Rubricering rapport Ongerubriceerd Vastgesteld... Auteur (s) dr. ir. M.M.J. Houben J.A. Verhave Rubricering rapport Ongerubriceerd TNO-rapport | TNO-DV 2008 A395 4/19 Summary Sound exposure level...ontwikkeld om de geluidsexpositie van CEPs te bepalen (TNO-project 032.13072, rapport TNO-DV 2008 A054) [1], In theorie kan het totale

  13. Sound exposure during outdoor music festivals

    Directory of Open Access Journals (Sweden)

    Tron V Tronstad

    2016-01-01

    Full Text Available Most countries have guidelines to regulate sound exposure at concerts and music festivals. These guidelines limit the allowed sound pressure levels and the concert/festival’s duration. In Norway, where there is such a guideline, it is up to the local authorities to impose the regulations. The need to prevent hearing-loss among festival participants is self-explanatory, but knowledge of the actual dose received by visitors is extremely scarce. This study looks at two Norwegian music festivals where only one was regulated by the Norwegian guideline for concert and music festivals. At each festival the sound exposure of four participants was monitored with noise dose meters. This study compared the exposures experienced at the two festivals, and tested them against the Norwegian guideline and the World Health Organization’s recommendations. Sound levels during the concerts were higher at the festival not regulated by any guideline, and levels there exceeded both the national and the Worlds Health Organization’s recommendations. The results also show that front-of-house measurements reliably predict participant exposure.

  14. Sound Exposure During Outdoor Music Festivals

    Science.gov (United States)

    Tronstad, Tron V.; Gelderblom, Femke B.

    2016-01-01

    Most countries have guidelines to regulate sound exposure at concerts and music festivals. These guidelines limit the allowed sound pressure levels and the concert/festival's duration. In Norway, where there is such a guideline, it is up to the local authorities to impose the regulations. The need to prevent hearing-loss among festival participants is self-explanatory, but knowledge of the actual dose received by visitors is extremely scarce. This study looks at two Norwegian music festivals where only one was regulated by the Norwegian guideline for concert and music festivals. At each festival the sound exposure of four participants was monitored with noise dose meters. This study compared the exposures experienced at the two festivals, and tested them against the Norwegian guideline and the World Health Organization's recommendations. Sound levels during the concerts were higher at the festival not regulated by any guideline, and levels there exceeded both the national and the Worlds Health Organization's recommendations. The results also show that front-of-house measurements reliably predict participant exposure. PMID:27569410

  15. Time and frequency weightings and the assessment of sound exposure

    DEFF Research Database (Denmark)

    Ordoñez, Rodrigo Pizarro; de Toro, Miguel Angel Aranda; Hammershøi, Dorte

    2010-01-01

    Since the development of averaging/integrating sound level meters and frequency weighting networks in the 1950’s, measurement of the physical characteristics of sound has not changed a great deal. Advances have occurred in how the measured values are used (day-night averages, limit and action...... of the exposure. This information is being used to investigate metrics that can differentiate temporal characteristics (impulsive, fluctuating) as well as frequency characteristics (narrow-band or tonal dominance) of sound exposures. This presentation gives an overview of the existing sound measurement...... and analysis methods, that can provide a better representation of the effects of sound exposures on the hearing system...

  16. A Model to Determine the Level of Serum Aldosterone in the Workers Attributed to the Combined Effects of Sound Pressure Level, Exposure Time and Serum Potassium Level: A Field-Based Study

    Directory of Open Access Journals (Sweden)

    Parvin Nassiri

    2016-09-01

    Full Text Available Background Occupational exposure to excessive noise is one of the biggest work-related challenges in the world. This phenomenon causes the release of stress-related hormones, which in turn, negatively affects cardiovascular risk factors. Objectives The current study study aimed to determine the level of workers’ serum aldosterone in light of the combined effect of sound pressure level, exposure time and serum potassium level. Methods This cross-sectional, descriptive, analytical study was conducted on 45 workers of Gol-Gohar Mining and Industrial Company in the fall of 2014. The subjects were divided into three groups (one control and two case groups, each including 15 workers. Participants in the control group were selected from workers with administrative jobs (exposure to the background noise. On the other hand, participants in the case groups were selected from the concentrator and pelletizing factories exposed to excessive noise. Serum aldosterone and potassium levels of participants were assessed at three different time intervals: at the beginning of the shift and before exposure to noise (7:30 - 8:00 AM, during exposure to noise (10:00 - 10:30 AM, and during continuous exposure (1:30 - 2:00 PM. The obtained data were transferred into SPSS ver. 18. Repeated measures analysis of variance (ANOVA was used to develop the statistical model of workers’ aldosterone level in light of the combined effect of sound pressure level, exposure time, and serum potassium level. Results The results of the final statistical model to determine the level of serum aldosterone based on the combined effect of sound pressure level, exposure time and serum potassium level indicated that the sound pressure level had a significant influence on the human’s serum aldosterone level (P = 0.04. In addition, the effects of exposure time and serum potassium on aldosterone level were statistically significant with P-values of 0.008 and 0.001, respectively. Conclusions

  17. Comprehensive measures of sound exposures in cinemas using smart phones.

    Science.gov (United States)

    Huth, Markus E; Popelka, Gerald R; Blevins, Nikolas H

    2014-01-01

    Sensorineural hearing loss from sound overexposure has a considerable prevalence. Identification of sound hazards is crucial, as prevention, due to a lack of definitive therapies, is the sole alternative to hearing aids. One subjectively loud, yet little studied, potential sound hazard is movie theaters. This study uses smart phones to evaluate their applicability as a widely available, validated sound pressure level (SPL) meter. Therefore, this study measures sound levels in movie theaters to determine whether sound levels exceed safe occupational noise exposure limits and whether sound levels in movie theaters differ as a function of movie, movie theater, presentation time, and seat location within the theater. Six smart phones with an SPL meter software application were calibrated with a precision SPL meter and validated as an SPL meter. Additionally, three different smart phone generations were measured in comparison to an integrating SPL meter. Two different movies, an action movie and a children's movie, were measured six times each in 10 different venues (n = 117). To maximize representativeness, movies were selected focusing on large release productions with probable high attendance. Movie theaters were selected in the San Francisco, CA, area based on whether they screened both chosen movies and to represent the largest variety of theater proprietors. Measurements were analyzed in regard to differences between theaters, location within the theater, movie, as well as presentation time and day as indirect indicator of film attendance. The smart phone measurements demonstrated high accuracy and reliability. Overall, sound levels in movie theaters do not exceed safe exposure limits by occupational standards. Sound levels vary significantly across theaters and demonstrated statistically significant higher sound levels and exposures in the action movie compared to the children's movie. Sound levels decrease with distance from the screen. However, no influence on

  18. Sound exposure measurements using hearing-aid technology

    DEFF Research Database (Denmark)

    Jensen, Simon Boelt; Drastrup, Mads; Morales, Esteban Chávez

    2016-01-01

    scenarios. The purpose of this work is to document the use of a modified behind-the-ear (BTE) hearing-aid as a portable sound pressure level (SPL) meter. In order to obtain sound level measurements with a BTE device comparable to sound field values that can be used with existing risk assessment strategies...... levels of sound exposures are experienced in modern society in many different situations such as attending concerts, sport events and others. This leads to an interest in measurement devices which are discreet and simple to use, in order to assess sound exposures encountered in typical daily life......, differences due to microphone positions and the presence of a person in the measurement must be taken into account. The present study presents measurements carried out to document the characteristics of the BTE device, using the same framework presented in the ISO 11904 standard series. The responses...

  19. Sound Levels and Risk Perceptions of Music Students During Classes.

    Science.gov (United States)

    Rodrigues, Matilde A; Amorim, Marta; Silva, Manuela V; Neves, Paula; Sousa, Aida; Inácio, Octávio

    2015-01-01

    It is well recognized that professional musicians are at risk of hearing damage due to the exposure to high sound pressure levels during music playing. However, it is important to recognize that the musicians' exposure may start early in the course of their training as students in the classroom and at home. Studies regarding sound exposure of music students and their hearing disorders are scarce and do not take into account important influencing variables. Therefore, this study aimed to describe sound level exposures of music students at different music styles, classes, and according to the instrument played. Further, this investigation attempted to analyze the perceptions of students in relation to exposure to loud music and consequent health risks, as well as to characterize preventive behaviors. The results showed that music students are exposed to high sound levels in the course of their academic activity. This exposure is potentiated by practice outside the school and other external activities. Differences were found between music style, instruments, and classes. Tinnitus, hyperacusis, diplacusis, and sound distortion were reported by the students. However, students were not entirely aware of the health risks related to exposure to high sound pressure levels. These findings reflect the importance of starting intervention in relation to noise risk reduction at an early stage, when musicians are commencing their activity as students.

  20. A level switch with a sound tube

    OpenAIRE

    赤池, 誠規

    2017-01-01

    Level switches are sensor with an electrical contact output at a specific liquid, powder or bulk level. Most of traditional level switches are not suitable for harsh environments. The level switch in this study connects a loudspeaker on top end of the sound tube. When liquid, powder or bulk closes bottom end of the sound tube, the level switch turns on. The level switch is suitable for harsh environments and easy to install. The aim of this study is to propose a level switch with a sound tube...

  1. Offshore dredger sounds: Source levels, sound maps, and risk assessment

    NARCIS (Netherlands)

    Jong, C.A.F. de; Ainslie, M.A.; Heinis, F.; Janmaat, J.

    2016-01-01

    The underwater sound produced during construction of the Port of Rotterdam harbor extension (Maasvlakte 2) was measured, with emphasis on the contribution of the trailing suction hopper dredgers during their various activities: dredging, transport, and discharge of sediment. Measured source levels

  2. Sound Levels in East Texas Schools.

    Science.gov (United States)

    Turner, Aaron Lynn

    A survey of sound levels was taken in several Texas schools to determine the amount of noise and sound present by size of class, type of activity, location of building, and the presence of air conditioning and large amounts of glass. The data indicate that class size and relative amounts of glass have no significant bearing on the production of…

  3. Field study of sound exposure by personal stereo

    DEFF Research Database (Denmark)

    Ordoñez, Rodrigo Pizarro; Reuter, Karen; Hammershøi, Dorte

    2006-01-01

    A number of large scale studies suggest that the exposure level used with personal stereo systems should raise concern. High levels can be produced by most commercially available mp3 players, and they are generally used in high background noise levels (i.e., while in a bus or rain). A field study...... on young people's habitual sound exposure to personal stereos has been carried out using a measurement method according to principles of ISO 11904-2:2004. Additionally the state of their hearing has also been assessed. This presentation deals with the methodological aspects relating to the quantification...... of habitual use, estimation of listening levels and exposure levels, and assessment of their state of hearing, by either threshold determination or OAE measurement, with a special view to the general validity of the results (uncertainty factors and their magnitude)....

  4. Time characteristics of distortion product otoacoustic emissions recovery function after moderate sound exposure

    DEFF Research Database (Denmark)

    de Toro, Miguel Angel Aranda; Ordoñez, Rodrigo Pizarro; Hammershøi, Dorte

    2006-01-01

    Exposure to sound of moderate level temporarily attenuates the amplitude of distortion product otoacoustic emissions (DPOAEs). These changes are similar to the changes observed in absolute hearing thresholds after similar sound exposures. To be able to assess changes over time across a broad...

  5. Underwater Sound Propagation Modeling Methods for Predicting Marine Animal Exposure.

    Science.gov (United States)

    Hamm, Craig A; McCammon, Diana F; Taillefer, Martin L

    2016-01-01

    The offshore exploration and production (E&P) industry requires comprehensive and accurate ocean acoustic models for determining the exposure of marine life to the high levels of sound used in seismic surveys and other E&P activities. This paper reviews the types of acoustic models most useful for predicting the propagation of undersea noise sources and describes current exposure models. The severe problems caused by model sensitivity to the uncertainty in the environment are highlighted to support the conclusion that it is vital that risk assessments include transmission loss estimates with statistical measures of confidence.

  6. Operating room sound level hazards for patients and physicians.

    Science.gov (United States)

    Fritsch, Michael H; Chacko, Chris E; Patterson, Emily B

    2010-07-01

    Exposure to certain new surgical instruments and operating room devices during procedures could cause hearing damage to patients and personnel. Surgical instruments and related equipment generate significant sound levels during routine usage. Both patients and physicians are exposed to these levels during the operative cases, many of which can last for hours. The noise loads during cases are cumulative. Occupational Safety and Health Administration (OSHA) and National Institute for Occupational Safety and Health (NIOSH) standards are inconsistent in their appraisals of potential damage. Implications of the newer power instruments are not widely recognized. Bruel and Kjaer sound meter spectral recordings for 20 major instruments from 5 surgical specialties were obtained at the ear levels for the patient and the surgeon between 32 and 20 kHz. Routinely used instruments generated sound levels as high as 131 dB. Patient and operator exposures differed. There were unilateral dominant exposures. Many instruments had levels that became hazardous well within the length of an average surgical procedure. The OSHA and NIOSH systems gave contradicting results when applied to individual instruments and types of cases. Background noise, especially in its intermittent form, was also of significant nature. Some patients and personnel have additional predisposing physiologic factors. Instrument noise levels for average length surgical cases may exceed OSHA and NIOSH recommendations for hearing safety. Specialties such as Otolaryngology, Orthopedics, and Neurosurgery use instruments that regularly exceed limits. General operating room noise also contributes to overall personnel exposures. Innovative countermeasures are suggested.

  7. Artifact rejection of distortion product otoacoustic emissions measured after sound exposure

    DEFF Research Database (Denmark)

    Reuter, Karen; Ordoñez, Rodrigo Pizarro; de Toro, Miguel Angel Aranda

    2007-01-01

    In a previous study [3] distortion product otoacoustic emissions (DPOAEs) were measured both before and after a moderate sound exposure, which caused a reduction of DPOAE levels. After the exposure DPOAEs had often levels below the noise floor. In the present paper it is discussed, whether...

  8. MECHANICAL HEART-VALVE PROSTHESES - SOUND LEVEL AND RELATED COMPLAINTS

    NARCIS (Netherlands)

    LAURENS, RRP; WIT, HP; EBELS, T

    In a randomised study, we investigated the sound production of mechanical heart valve prostheses and the complaints related to this sound. The CarboMedics, Bjork-Shiley monostrut and StJude Medical prostheses were compared. A-weighted levels of the pulse-like sound produced by the prosthesis were

  9. Can road traffic mask sound from wind turbines? Response to wind turbine sound at different levels of road traffic sound

    International Nuclear Information System (INIS)

    Pedersen, Eja; Berg, Frits van den; Bakker, Roel; Bouma, Jelte

    2010-01-01

    Wind turbines are favoured in the switch-over to renewable energy. Suitable sites for further developments could be difficult to find as the sound emitted from the rotor blades calls for a sufficient distance to residents to avoid negative effects. The aim of this study was to explore if road traffic sound could mask wind turbine sound or, in contrast, increases annoyance due to wind turbine noise. Annoyance of road traffic and wind turbine noise was measured in the WINDFARMperception survey in the Netherlands in 2007 (n=725) and related to calculated levels of sound. The presence of road traffic sound did not in general decrease annoyance with wind turbine noise, except when levels of wind turbine sound were moderate (35-40 dB(A) Lden) and road traffic sound level exceeded that level with at least 20 dB(A). Annoyance with both noises was intercorrelated but this correlation was probably due to the influence of individual factors. Furthermore, visibility and attitude towards wind turbines were significantly related to noise annoyance of modern wind turbines. The results can be used for the selection of suitable sites, possibly favouring already noise exposed areas if wind turbine sound levels are sufficiently low.

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

    Directory of Open Access Journals (Sweden)

    Arthur N Popper

    Full Text Available 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.

  11. Recovery of barotrauma injuries in Chinook salmon, Oncorhynchus tshawytscha from exposure to pile driving sound.

    Directory of Open Access Journals (Sweden)

    Brandon M Casper

    Full Text Available Juvenile Chinook salmon, Oncorhynchus tshawytscha, were exposed to simulated high intensity pile driving signals to evaluate their ability to recover from barotrauma injuries. Fish were exposed to one of two cumulative sound exposure levels for 960 pile strikes (217 or 210 dB re 1 µPa(2·s SEL(cum; single strike sound exposure levels of 187 or 180 dB re 1 µPa(2⋅s SEL(ss respectively. This was followed by an immediate assessment of injuries, or assessment 2, 5, or 10 days post-exposure. There were no observed mortalities from the pile driving sound exposure. Fish exposed to 217 dB re 1 µPa(2·s SEL(cum displayed evidence of healing from injuries as post-exposure time increased. Fish exposed to 210 dB re 1 µPa(2·s SEL(cum sustained minimal injuries that were not significantly different from control fish at days 0, 2, and 10. The exposure to 210 dB re 1 µPa(2·s SEL(cum replicated the findings in a previous study that defined this level as the threshold for onset of injury. Furthermore, these data support the hypothesis that one or two Mild injuries resulting from pile driving exposure are unlikely to affect the survival of the exposed animals, at least in a laboratory environment.

  12. Sound level measurements using smartphone "apps": Useful or inaccurate?

    Directory of Open Access Journals (Sweden)

    Daniel R Nast

    2014-01-01

    Full Text Available Many recreational activities are accompanied by loud concurrent sounds and decisions regarding the hearing hazards associated with these activities depend on accurate sound measurements. Sound level meters (SLMs are designed for this purpose, but these are technical instruments that are not typically available in recreational settings and require training to use properly. Mobile technology has made such sound level measurements more feasible for even inexperienced users. Here, we assessed the accuracy of sound level measurements made using five mobile phone applications or "apps" on an Apple iPhone 4S, one of the most widely used mobile phones. Accuracy was assessed by comparing application-based measurements to measurements made using a calibrated SLM. Whereas most apps erred by reporting higher sound levels, one application measured levels within 5 dB of a calibrated SLM across all frequencies tested.

  13. A- and C-weighted sound levels as predictors of the annoyance caused by shooting sounds, for various facade attenuation types

    NARCIS (Netherlands)

    Vos, J.

    2003-01-01

    In a previous study on the annoyance caused by a great variety of shooting sounds [J. Acoust. Soc. Am. 109, 244-253 (2001)], it was shown that the annoyance, as rated indoors with the windows closed, could be adequately predicted from the outdoor A-weighted and C-weighted sound-exposure levels [ASEL

  14. Balancing speech intelligibility versus sound exposure in selection of personal hearing protection equipment for Chinook aircrews

    NARCIS (Netherlands)

    Wijngaarden, S.J. van; Rots, G.

    2001-01-01

    Background: Aircrews are often exposed to high ambient sound levels, especially in military aviation. Since long-term exposure to such noise may cause hearing damage, selection of adequate hearing protective devices is crucial. Such devices also affect speech intelligibility. When speech

  15. Sound Exposure of Healthcare Professionals Working with a University Marching Band.

    Science.gov (United States)

    Russell, Jeffrey A; Yamaguchi, Moegi

    2018-01-01

    Music-induced hearing disorders are known to result from exposure to excessive levels of music of different genres. Marching band music, with its heavy emphasis on brass and percussion, is one type that is a likely contributor to music-induced hearing disorders, although specific data on sound pressure levels of marching bands have not been widely studied. Furthermore, if marching band music does lead to music-induced hearing disorders, the musicians may not be the only individuals at risk. Support personnel such as directors, equipment managers, and performing arts healthcare providers may also be exposed to potentially damaging sound pressures. Thus, we sought to explore to what degree healthcare providers receive sound dosages above recommended limits during their work with a marching band. The purpose of this study was to determine the sound exposure of healthcare professionals (specifically, athletic trainers [ATs]) who provide on-site care to a large, well-known university marching band. We hypothesized that sound pressure levels to which these individuals were exposed would exceed the National Institute for Occupational Safety and Health (NIOSH) daily percentage allowance. Descriptive observational study. Eight ATs working with a well-known American university marching band volunteered to wear noise dosimeters. During the marching band season, ATs wore an Etymotic ER-200D dosimeter whenever working with the band at outdoor rehearsals, indoor field house rehearsals, and outdoor performances. The dosimeters recorded dose percent exposure, equivalent continuous sound levels in A-weighted decibels, and duration of exposure. For comparison, a dosimeter also was worn by an AT working in the university's performing arts medicine clinic. Participants did not alter their typical duties during any data collection sessions. Sound data were collected with the dosimeters set at the NIOSH standards of 85 dBA threshold and 3 dBA exchange rate; the NIOSH 100% daily dose is

  16. Differences between Outdoor and Indoor Sound Levels for Open, Tilted, and Closed Windows.

    Science.gov (United States)

    Locher, Barbara; Piquerez, André; Habermacher, Manuel; Ragettli, Martina; Röösli, Martin; Brink, Mark; Cajochen, Christian; Vienneau, Danielle; Foraster, Maria; Müller, Uwe; Wunderli, Jean Marc

    2018-01-18

    Noise exposure prediction models for health effect studies normally estimate free field exposure levels outside. However, to assess the noise exposure inside dwellings, an estimate of indoor sound levels is necessary. To date, little field data is available about the difference between indoor and outdoor noise levels and factors affecting the damping of outside noise. This is a major cause of uncertainty in indoor noise exposure prediction and may lead to exposure misclassification in health assessments. This study aims to determine sound level differences between the indoors and the outdoors for different window positions and how this sound damping is related to building characteristics. For this purpose, measurements were carried out at home in a sample of 102 Swiss residents exposed to road traffic noise. Sound pressure level recordings were performed outdoors and indoors, in the living room and in the bedroom. Three scenarios-of open, tilted, and closed windows-were recorded for three minutes each. For each situation, data on additional parameters such as the orientation towards the source, floor, and room, as well as sound insulation characteristics were collected. On that basis, linear regression models were established. The median outdoor-indoor sound level differences were of 10 dB(A) for open, 16 dB(A) for tilted, and 28 dB(A) for closed windows. For open and tilted windows, the most relevant parameters affecting the outdoor-indoor differences were the position of the window, the type and volume of the room, and the age of the building. For closed windows, the relevant parameters were the sound level outside, the material of the window frame, the existence of window gaskets, and the number of windows.

  17. Differences between Outdoor and Indoor Sound Levels for Open, Tilted, and Closed Windows

    Science.gov (United States)

    Locher, Barbara; Piquerez, André; Habermacher, Manuel; Ragettli, Martina; Cajochen, Christian; Vienneau, Danielle; Foraster, Maria; Müller, Uwe; Wunderli, Jean Marc

    2018-01-01

    Noise exposure prediction models for health effect studies normally estimate free field exposure levels outside. However, to assess the noise exposure inside dwellings, an estimate of indoor sound levels is necessary. To date, little field data is available about the difference between indoor and outdoor noise levels and factors affecting the damping of outside noise. This is a major cause of uncertainty in indoor noise exposure prediction and may lead to exposure misclassification in health assessments. This study aims to determine sound level differences between the indoors and the outdoors for different window positions and how this sound damping is related to building characteristics. For this purpose, measurements were carried out at home in a sample of 102 Swiss residents exposed to road traffic noise. Sound pressure level recordings were performed outdoors and indoors, in the living room and in the bedroom. Three scenarios—of open, tilted, and closed windows—were recorded for three minutes each. For each situation, data on additional parameters such as the orientation towards the source, floor, and room, as well as sound insulation characteristics were collected. On that basis, linear regression models were established. The median outdoor–indoor sound level differences were of 10 dB(A) for open, 16 dB(A) for tilted, and 28 dB(A) for closed windows. For open and tilted windows, the most relevant parameters affecting the outdoor–indoor differences were the position of the window, the type and volume of the room, and the age of the building. For closed windows, the relevant parameters were the sound level outside, the material of the window frame, the existence of window gaskets, and the number of windows. PMID:29346318

  18. A Two-Level Sound Classification Platform for Environmental Monitoring

    Directory of Open Access Journals (Sweden)

    Stelios A. Mitilineos

    2018-01-01

    Full Text Available STORM is an ongoing European research project that aims at developing an integrated platform for monitoring, protecting, and managing cultural heritage sites through technical and organizational innovation. Part of the scheduled preventive actions for the protection of cultural heritage is the development of wireless acoustic sensor networks (WASNs that will be used for assessing the impact of human-generated activities as well as for monitoring potentially hazardous environmental phenomena. Collected sound samples will be forwarded to a central server where they will be automatically classified in a hierarchical manner; anthropogenic and environmental activity will be monitored, and stakeholders will be alarmed in the case of potential malevolent behavior or natural phenomena like excess rainfall, fire, gale, high tides, and waves. Herein, we present an integrated platform that includes sound sample denoising using wavelets, feature extraction from sound samples, Gaussian mixture modeling of these features, and a powerful two-layer neural network for automatic classification. We contribute to previous work by extending the proposed classification platform to perform low-level classification too, i.e., classify sounds to further subclasses that include airplane, car, and pistol sounds for the anthropogenic sound class; bird, dog, and snake sounds for the biophysical sound class; and fire, waterfall, and gale for the geophysical sound class. Classification results exhibit outstanding classification accuracy in both high-level and low-level classification thus demonstrating the feasibility of the proposed approach.

  19. Decoding sound level in the marmoset primary auditory cortex.

    Science.gov (United States)

    Sun, Wensheng; Marongelli, Ellisha N; Watkins, Paul V; Barbour, Dennis L

    2017-10-01

    Neurons that respond favorably to a particular sound level have been observed throughout the central auditory system, becoming steadily more common at higher processing areas. One theory about the role of these level-tuned or nonmonotonic neurons is the level-invariant encoding of sounds. To investigate this theory, we simulated various subpopulations of neurons by drawing from real primary auditory cortex (A1) neuron responses and surveyed their performance in forming different sound level representations. Pure nonmonotonic subpopulations did not provide the best level-invariant decoding; instead, mixtures of monotonic and nonmonotonic neurons provided the most accurate decoding. For level-fidelity decoding, the inclusion of nonmonotonic neurons slightly improved or did not change decoding accuracy until they constituted a high proportion. These results indicate that nonmonotonic neurons fill an encoding role complementary to, rather than alternate to, monotonic neurons. NEW & NOTEWORTHY Neurons with nonmonotonic rate-level functions are unique to the central auditory system. These level-tuned neurons have been proposed to account for invariant sound perception across sound levels. Through systematic simulations based on real neuron responses, this study shows that neuron populations perform sound encoding optimally when containing both monotonic and nonmonotonic neurons. The results indicate that instead of working independently, nonmonotonic neurons complement the function of monotonic neurons in different sound-encoding contexts. Copyright © 2017 the American Physiological Society.

  20. Exposure to arousal-inducing sounds facilitates visual search.

    Science.gov (United States)

    Asutay, Erkin; Västfjäll, Daniel

    2017-09-04

    Exposure to affective stimuli could enhance perception and facilitate attention via increasing alertness, vigilance, and by decreasing attentional thresholds. However, evidence on the impact of affective sounds on perception and attention is scant. Here, a novel aspect of affective facilitation of attention is studied: whether arousal induced by task-irrelevant auditory stimuli could modulate attention in a visual search. In two experiments, participants performed a visual search task with and without auditory-cues that preceded the search. Participants were faster in locating high-salient targets compared to low-salient targets. Critically, search times and search slopes decreased with increasing auditory-induced arousal while searching for low-salient targets. Taken together, these findings suggest that arousal induced by sounds can facilitate attention in a subsequent visual search. This novel finding provides support for the alerting function of the auditory system by showing an auditory-phasic alerting effect in visual attention. The results also indicate that stimulus arousal modulates the alerting effect. Attention and perception are our everyday tools to navigate our surrounding world and the current findings showing that affective sounds could influence visual attention provide evidence that we make use of affective information during perceptual processing.

  1. MP3 player listening sound pressure levels among 10 to 17 year old students.

    Science.gov (United States)

    Keith, Stephen E; Michaud, David S; Feder, Katya; Haider, Ifaz; Marro, Leonora; Thompson, Emma; Marcoux, Andre M

    2011-11-01

    Using a manikin, equivalent free-field sound pressure level measurements were made from the portable digital audio players of 219 subjects, aged 10 to 17 years (93 males) at their typical and "worst-case" volume levels. Measurements were made in different classrooms with background sound pressure levels between 40 and 52 dBA. After correction for the transfer function of the ear, the median equivalent free field sound pressure levels and interquartile ranges (IQR) at typical and worst-case volume settings were 68 dBA (IQR = 15) and 76 dBA (IQR = 19), respectively. Self-reported mean daily use ranged from 0.014 to 12 h. When typical sound pressure levels were considered in combination with the average daily duration of use, the median noise exposure level, Lex, was 56 dBA (IQR = 18) and 3.2% of subjects were estimated to exceed the most protective occupational noise exposure level limit in Canada, i.e., 85 dBA Lex. Under worst-case listening conditions, 77.6% of the sample was estimated to listen to their device at combinations of sound pressure levels and average daily durations for which there is no known risk of permanent noise-induced hearing loss, i.e., ≤  75 dBA Lex. Sources and magnitudes of measurement uncertainties are also discussed.

  2. Opponent Coding of Sound Location (Azimuth) in Planum Temporale is Robust to Sound-Level Variations.

    Science.gov (United States)

    Derey, Kiki; Valente, Giancarlo; de Gelder, Beatrice; Formisano, Elia

    2016-01-01

    Coding of sound location in auditory cortex (AC) is only partially understood. Recent electrophysiological research suggests that neurons in mammalian auditory cortex are characterized by broad spatial tuning and a preference for the contralateral hemifield, that is, a nonuniform sampling of sound azimuth. Additionally, spatial selectivity decreases with increasing sound intensity. To accommodate these findings, it has been proposed that sound location is encoded by the integrated activity of neuronal populations with opposite hemifield tuning ("opponent channel model"). In this study, we investigated the validity of such a model in human AC with functional magnetic resonance imaging (fMRI) and a phase-encoding paradigm employing binaural stimuli recorded individually for each participant. In all subjects, we observed preferential fMRI responses to contralateral azimuth positions. Additionally, in most AC locations, spatial tuning was broad and not level invariant. We derived an opponent channel model of the fMRI responses by subtracting the activity of contralaterally tuned regions in bilateral planum temporale. This resulted in accurate decoding of sound azimuth location, which was unaffected by changes in sound level. Our data thus support opponent channel coding as a neural mechanism for representing acoustic azimuth in human AC. © The Author 2015. Published by Oxford University Press.

  3. Behavioural changes in response to sound exposure and no spatial avoidance of noisy conditions in captive zebrafish

    Directory of Open Access Journals (Sweden)

    Yik Yaw (Errol eNeo

    2015-02-01

    Full Text Available Auditory sensitivity in fish serves various important functions, but also makes fish susceptible to noise pollution. Human-generated sounds may affect behavioural patterns of fish, both in natural conditions and in captivity. Fish are often kept for consumption in aquaculture, on display in zoos and hobby aquaria, and for medical sciences in research facilities, but little is known about the impact of ambient sounds in fish tanks. In this study, we conducted two indoor exposure experiments with zebrafish (Danio rerio. The first experiment demonstrated that exposure to moderate sound levels (112 dB re 1 μPa can affect the swimming behaviour of fish by changing group cohesion, swimming speed and swimming height. Effects were brief for both continuous and intermittent noise treatments. In the second experiment, fish could influence exposure to higher sound levels by swimming freely between an artificially noisy fish tank (120-140 dB re 1 μPa and another with ambient noise levels (89 dB re 1 μPa. Despite initial startle responses, and a brief period in which many individuals in the noisy tank dived down to the bottom, there was no spatial avoidance or noise-dependent tank preference at all. The frequent exchange rate of about 60 fish passages per hour between tanks was not affected by continuous or intermittent exposures. In conclusion, small groups of captive zebrafish were able to detect sounds already at relatively low sound levels and adjust their behaviour to it. Relatively high sound levels were at least at the on-set disturbing, but did not lead to spatial avoidance. Further research is needed to show whether zebrafish are not able to avoid noisy areas or just not bothered. Quantitatively, these data are not directly applicable to other fish species or other fish tanks, but they do indicate that sound exposure may affect fish behaviour in any captive condition.

  4. Behavioral changes in response to sound exposure and no spatial avoidance of noisy conditions in captive zebrafish.

    Science.gov (United States)

    Neo, Yik Yaw; Parie, Lisa; Bakker, Frederique; Snelderwaard, Peter; Tudorache, Christian; Schaaf, Marcel; Slabbekoorn, Hans

    2015-01-01

    Auditory sensitivity in fish serves various important functions, but also makes fish susceptible to noise pollution. Human-generated sounds may affect behavioral patterns of fish, both in natural conditions and in captivity. Fish are often kept for consumption in aquaculture, on display in zoos and hobby aquaria, and for medical sciences in research facilities, but little is known about the impact of ambient sounds in fish tanks. In this study, we conducted two indoor exposure experiments with zebrafish (Danio rerio). The first experiment demonstrated that exposure to moderate sound levels (112 dB re 1 μPa) can affect the swimming behavior of fish by changing group cohesion, swimming speed and swimming height. Effects were brief for both continuous and intermittent noise treatments. In the second experiment, fish could influence exposure to higher sound levels by swimming freely between an artificially noisy fish tank (120-140 dB re 1 μPa) and another with ambient noise levels (89 dB re 1 μPa). Despite initial startle responses, and a brief period in which many individuals in the noisy tank dived down to the bottom, there was no spatial avoidance or noise-dependent tank preference at all. The frequent exchange rate of about 60 fish passages per hour between tanks was not affected by continuous or intermittent exposures. In conclusion, small groups of captive zebrafish were able to detect sounds already at relatively low sound levels and adjust their behavior to it. Relatively high sound levels were at least at the on-set disturbing, but did not lead to spatial avoidance. Further research is needed to show whether zebrafish are not able to avoid noisy areas or just not bothered. Quantitatively, these data are not directly applicable to other fish species or other fish tanks, but they do indicate that sound exposure may affect fish behavior in any captive condition.

  5. Analysis of sound pressure levels emitted by children's toys.

    Science.gov (United States)

    Sleifer, Pricila; Gonçalves, Maiara Santos; Tomasi, Marinês; Gomes, Erissandra

    2013-06-01

    To verify the levels of sound pressure emitted by non-certified children's toys. Cross-sectional study of sound toys available at popular retail stores of the so-called informal sector. Electronic, mechanical, and musical toys were analyzed. The measurement of each product was carried out by an acoustic engineer in an acoustically isolated booth, by a decibel meter. To obtain the sound parameters of intensity and frequency, the toys were set to produce sounds at a distance of 10 and 50cm from the researcher's ear. The intensity of sound pressure [dB(A)] and the frequency in hertz (Hz) were measured. 48 toys were evaluated. The mean sound pressure 10cm from the ear was 102±10 dB(A), and at 50cm, 94±8 dB(A), with ptoys was above 85dB(A). The frequency ranged from 413 to 6,635Hz, with 56.3% of toys emitting frequency higher than 2,000Hz. The majority of toys assessed in this research emitted a high level of sound pressure.

  6. Sound pressure level tools design used in occupational health by means of Labview software

    Directory of Open Access Journals (Sweden)

    Farhad Forouharmajd

    2015-01-01

    Conclusion: LabVIEW programming capabilities in the field of sound can be referred to the measurement of sound, frequency analysis, and sound control that actually the software acts like a sound level meter and sound analyzer. According to the mentioned features, we can use this software to analyze and process sound and vibration as a monitoring system.

  7. Behavioral response of manatees to variations in environmental sound levels

    Science.gov (United States)

    Miksis-Olds, Jennifer L.; Wagner, Tyler

    2011-01-01

    Florida manatees (Trichechus manatus latirostris) inhabit coastal regions because they feed on the aquatic vegetation that grows in shallow waters, which are the same areas where human activities are greatest. Noise produced from anthropogenic and natural sources has the potential to affect these animals by eliciting responses ranging from mild behavioral changes to extreme aversion. Sound levels were calculated from recordings made throughout behavioral observation periods. An information theoretic approach was used to investigate the relationship between behavior patterns and sound level. Results indicated that elevated sound levels affect manatee activity and are a function of behavioral state. The proportion of time manatees spent feeding and milling changed in response to sound level. When ambient sound levels were highest, more time was spent in the directed, goal-oriented behavior of feeding, whereas less time was spent engaged in undirected behavior such as milling. This work illustrates how shifts in activity of individual manatees may be useful parameters for identifying impacts of noise on manatees and might inform population level effects.

  8. Effects of interaural level differences on the externalization of sound

    DEFF Research Database (Denmark)

    Catic, Jasmina; Santurette, Sébastien; Dau, Torsten

    2012-01-01

    Distant sound sources in our environment are perceived as externalized and are thus properly localized in both direction and distance. This is due to the acoustic filtering by the head, torso, and external ears, which provides frequency-dependent shaping of binaural cues such as interaural level...... differences (ILDs) and interaural time differences (ITDs). In rooms, the sound reaching the two ears is further modified by reverberant energy, which leads to increased fluctuations in short-term ILDs and ITDs. In the present study, the effect of ILD fluctuations on the externalization of sound......, for sounds that contain frequencies above about 1 kHz the ILD fluctuations were found to be an essential cue for externalization....

  9. Four odontocete species change hearing levels when warned of impending loud sound.

    Science.gov (United States)

    Nachtigall, Paul E; Supin, Alexander Ya; Pacini, Aude F; Kastelein, Ronald A

    2018-03-01

    Hearing sensitivity change was investigated when a warning sound preceded a loud sound in the false killer whale (Pseudorca crassidens), the bottlenose dolphin (Tursiops truncatus), the beluga whale (Delphinaperus leucas) and the harbor porpoise (Phocoena phocoena). Hearing sensitivity was measured using pip-train test stimuli and auditory evoked potential recording. When the test/warning stimuli preceded a loud sound, hearing thresholds before the loud sound increased relative to the baseline by 13 to 17 dB. Experiments with multiple frequencies of exposure and shift provided evidence of different amounts of hearing change depending on frequency, indicating that the hearing sensation level changes were not likely due to a simple stapedial reflex. © 2017 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  10. Offshore dredger sound: source levels, sound maps and risk assessment (abstract)

    NARCIS (Netherlands)

    Jong, C.A.F. de; Ainslie, M.A.; Heinis, F.; Janmaat, J.

    2013-01-01

    The Port of Rotterdam is expanding to meet the growing demand to accommodate large cargo vessels. One of the licensing conditions was the monitoring of the underwater sound produced during its construction, with an emphasis on the establishment of acoustic source levels of the Trailing Suction

  11. Tinnitus is associated with reduced sound level tolerance in adolescents with normal audiograms and otoacoustic emissions

    Science.gov (United States)

    Sanchez, Tanit Ganz; Moraes, Fernanda; Casseb, Juliana; Cota, Jaci; Freire, Katya; Roberts, Larry E.

    2016-01-01

    Recent neuroscience research suggests that tinnitus may reflect synaptic loss in the cochlea that does not express in the audiogram but leads to neural changes in auditory pathways that reduce sound level tolerance (SLT). Adolescents (N = 170) completed a questionnaire addressing their prior experience with tinnitus, potentially risky listening habits, and sensitivity to ordinary sounds, followed by psychoacoustic measurements in a sound booth. Among all adolescents 54.7% reported by questionnaire that they had previously experienced tinnitus, while 28.8% heard tinnitus in the booth. Psychoacoustic properties of tinnitus measured in the sound booth corresponded with those of chronic adult tinnitus sufferers. Neither hearing thresholds (≤15 dB HL to 16 kHz) nor otoacoustic emissions discriminated between adolescents reporting or not reporting tinnitus in the sound booth, but loudness discomfort levels (a psychoacoustic measure of SLT) did so, averaging 11.3 dB lower in adolescents experiencing tinnitus in the acoustic chamber. Although risky listening habits were near universal, the teenagers experiencing tinnitus and reduced SLT tended to be more protective of their hearing. Tinnitus and reduced SLT could be early indications of a vulnerability to hidden synaptic injury that is prevalent among adolescents and expressed following exposure to high level environmental sounds. PMID:27265722

  12. Wind turbine sound pressure level calculations at dwellings.

    Science.gov (United States)

    Keith, Stephen E; Feder, Katya; Voicescu, Sonia A; Soukhovtsev, Victor; Denning, Allison; Tsang, Jason; Broner, Norm; Leroux, Tony; Richarz, Werner; van den Berg, Frits

    2016-03-01

    This paper provides calculations of outdoor sound pressure levels (SPLs) at dwellings for 10 wind turbine models, to support Health Canada's Community Noise and Health Study. Manufacturer supplied and measured wind turbine sound power levels were used to calculate outdoor SPL at 1238 dwellings using ISO [(1996). ISO 9613-2-Acoustics] and a Swedish noise propagation method. Both methods yielded statistically equivalent results. The A- and C-weighted results were highly correlated over the 1238 dwellings (Pearson's linear correlation coefficient r > 0.8). Calculated wind turbine SPLs were compared to ambient SPLs from other sources, estimated using guidance documents from the United States and Alberta, Canada.

  13. Water-Level Analysis for Cumberland Sound, Georgia

    National Research Council Canada - National Science Library

    Kraus, Nicholas

    1997-01-01

    .... The channel through St Marys Entrance is maintained at a 50-ft depth through significant dredging that occurred from 1986-1988 Questions arose as to whether this dredging had raised the water level in Cumberland Sound. The U.S...

  14. Aging Affects Adaptation to Sound-Level Statistics in Human Auditory Cortex.

    Science.gov (United States)

    Herrmann, Björn; Maess, Burkhard; Johnsrude, Ingrid S

    2018-02-21

    Optimal perception requires efficient and adaptive neural processing of sensory input. Neurons in nonhuman mammals adapt to the statistical properties of acoustic feature distributions such that they become sensitive to sounds that are most likely to occur in the environment. However, whether human auditory responses adapt to stimulus statistical distributions and how aging affects adaptation to stimulus statistics is unknown. We used MEG to study how exposure to different distributions of sound levels affects adaptation in auditory cortex of younger (mean: 25 years; n = 19) and older (mean: 64 years; n = 20) adults (male and female). Participants passively listened to two sound-level distributions with different modes (either 15 or 45 dB sensation level). In a control block with long interstimulus intervals, allowing neural populations to recover from adaptation, neural response magnitudes were similar between younger and older adults. Critically, both age groups demonstrated adaptation to sound-level stimulus statistics, but adaptation was altered for older compared with younger people: in the older group, neural responses continued to be sensitive to sound level under conditions in which responses were fully adapted in the younger group. The lack of full adaptation to the statistics of the sensory environment may be a physiological mechanism underlying the known difficulty that older adults have with filtering out irrelevant sensory information. SIGNIFICANCE STATEMENT Behavior requires efficient processing of acoustic stimulation. Animal work suggests that neurons accomplish efficient processing by adjusting their response sensitivity depending on statistical properties of the acoustic environment. Little is known about the extent to which this adaptation to stimulus statistics generalizes to humans, particularly to older humans. We used MEG to investigate how aging influences adaptation to sound-level statistics. Listeners were presented with sounds drawn from

  15. Exposure to excessive sounds and hearing status in academic classical music students

    Directory of Open Access Journals (Sweden)

    Małgorzata Pawlaczyk-Łuszczyńska

    2017-02-01

    Full Text Available Objectives: The aim of this study was to assess hearing of music students in relation to their exposure to excessive sounds. Material and Methods: Standard pure-tone audiometry (PTA was performed in 168 music students, aged 22.5±2.5 years. The control group included 67 subjects, non-music students and non-musicians, aged 22.8±3.3 years. Data on the study subjects’ musical experience, instruments in use, time of weekly practice and additional risk factors for noise-induced hearing loss (NIHL were identified by means of a questionnaire survey. Sound pressure levels produced by various groups of instruments during solo and group playing were also measured and analyzed. The music students’ audiometric hearing threshold levels (HTLs were compared with the theoretical predictions calculated according to the International Organization for Standardization standard ISO 1999:2013. Results: It was estimated that the music students were exposed for 27.1±14.3 h/week to sounds at the A-weighted equivalent-continuous sound pressure level of 89.9±6.0 dB. There were no significant differences in HTLs between the music students and the control group in the frequency range of 4000–8000 Hz. Furthermore, in each group HTLs in the frequency range 1000–8000 Hz did not exceed 20 dB HL in 83% of the examined ears. Nevertheless, high frequency notched audiograms typical of the noise-induced hearing loss were found in 13.4% and 9% of the musicians and non-musicians, respectively. The odds ratio (OR of notching in the music students increased significantly along with higher sound pressure levels (OR = 1.07, 95% confidence interval (CI: 1.014–1.13, p < 0.05. The students’ HTLs were worse (higher than those of a highly screened non-noise-exposed population. Moreover, their hearing loss was less severe than that expected from sound exposure for frequencies of 3000 Hz and 4000 Hz, and it was more severe in the case of frequency of 6000 Hz. Conclusions: The

  16. Exposure to excessive sounds and hearing status in academic classical music students.

    Science.gov (United States)

    Pawlaczyk-Łuszczyńska, Małgorzata; Zamojska-Daniszewska, Małgorzata; Dudarewicz, Adam; Zaborowski, Kamil

    2017-02-21

    The aim of this study was to assess hearing of music students in relation to their exposure to excessive sounds. Standard pure-tone audiometry (PTA) was performed in 168 music students, aged 22.5±2.5 years. The control group included 67 subjects, non-music students and non-musicians, aged 22.8±3.3 years. Data on the study subjects' musical experience, instruments in use, time of weekly practice and additional risk factors for noise-induced hearing loss (NIHL) were identified by means of a questionnaire survey. Sound pressure levels produced by various groups of instruments during solo and group playing were also measured and analyzed. The music students' audiometric hearing threshold levels (HTLs) were compared with the theoretical predictions calculated according to the International Organization for Standardization standard ISO 1999:2013. It was estimated that the music students were exposed for 27.1±14.3 h/week to sounds at the A-weighted equivalent-continuous sound pressure level of 89.9±6.0 dB. There were no significant differences in HTLs between the music students and the control group in the frequency range of 4000-8000 Hz. Furthermore, in each group HTLs in the frequency range 1000-8000 Hz did not exceed 20 dB HL in 83% of the examined ears. Nevertheless, high frequency notched audiograms typical of the noise-induced hearing loss were found in 13.4% and 9% of the musicians and non-musicians, respectively. The odds ratio (OR) of notching in the music students increased significantly along with higher sound pressure levels (OR = 1.07, 95% confidence interval (CI): 1.014-1.13, p students' HTLs were worse (higher) than those of a highly screened non-noise-exposed population. Moreover, their hearing loss was less severe than that expected from sound exposure for frequencies of 3000 Hz and 4000 Hz, and it was more severe in the case of frequency of 6000 Hz. The results confirm the need for further studies and development of a hearing conservation program for

  17. Blast noise classification with common sound level meter metrics.

    Science.gov (United States)

    Cvengros, Robert M; Valente, Dan; Nykaza, Edward T; Vipperman, Jeffrey S

    2012-08-01

    A common set of signal features measurable by a basic sound level meter are analyzed, and the quality of information carried in subsets of these features are examined for their ability to discriminate military blast and non-blast sounds. The analysis is based on over 120 000 human classified signals compiled from seven different datasets. The study implements linear and Gaussian radial basis function (RBF) support vector machines (SVM) to classify blast sounds. Using the orthogonal centroid dimension reduction technique, intuition is developed about the distribution of blast and non-blast feature vectors in high dimensional space. Recursive feature elimination (SVM-RFE) is then used to eliminate features containing redundant information and rank features according to their ability to separate blasts from non-blasts. Finally, the accuracy of the linear and RBF SVM classifiers is listed for each of the experiments in the dataset, and the weights are given for the linear SVM classifier.

  18. SOUND LABOR RELATIONS AT ENTERPRISE LEVEL IN THAILAND

    Directory of Open Access Journals (Sweden)

    Vichai Thosuwonchinda

    2016-07-01

    Full Text Available The objective of this research was to study the pattern of sound labor relations in Thailand in order to reduce conflicts between employers and workers and create cooperation. The research was based on a qualitative approach, using in-depth interview with 10 stakeholder groups of Thai industrial relations system. They were employees of non unionized companies at the shop floor level, employees of non unionized companies at the supervisor level, trade union leaders at the company level, trade union leaders at the national level, employers of non-unionized companies, employers’ organization leaders, and human resource managers, members of tripartite bodies, government officials and labor academics. The findings were presented in a model identifying 5 characteristics that enhance sound relations in Thailand, i.e. recognition between employer and workers, good communication, trust, data revealing and workers’ participation. It was suggested that all parties, employers, workers and the government should take part in the promotion of sound labor relations. The employer have to acknowledge labor union with a positive attitude, have good communication with workers , create trust with workers, disclose information, create culture of mutual benefits as well as accept sincerely the system that include workers’ participation. Workers need a strong labor union, good and sincere representatives for clear communication, trust, mutual benefits and seek conflict solutions with employer by win-win strategy. The government has a supporting role in adjusting the existing laws in the appropriate way, by creating policy for sound labor relations, and putting the idea of sound labor relations into practice.

  19. Long-Term Impairment of Sound Processing in the Auditory Midbrain by Daily Short-Term Exposure to Moderate Noise

    Directory of Open Access Journals (Sweden)

    Liang Cheng

    2017-01-01

    Full Text Available Most citizen people are exposed daily to environmental noise at moderate levels with a short duration. The aim of the present study was to determine the effects of daily short-term exposure to moderate noise on sound level processing in the auditory midbrain. Sound processing properties of auditory midbrain neurons were recorded in anesthetized mice exposed to moderate noise (80 dB SPL, 2 h/d for 6 weeks and were compared with those from age-matched controls. Neurons in exposed mice had a higher minimum threshold and maximum response intensity, a longer first spike latency, and a higher slope and narrower dynamic range for rate level function. However, these observed changes were greater in neurons with the best frequency within the noise exposure frequency range compared with those outside the frequency range. These sound processing properties also remained abnormal after a 12-week period of recovery in a quiet laboratory environment after completion of noise exposure. In conclusion, even daily short-term exposure to moderate noise can cause long-term impairment of sound level processing in a frequency-specific manner in auditory midbrain neurons.

  20. Sound

    CERN Document Server

    Robertson, William C

    2003-01-01

    Muddled about what makes music? Stuck on the study of harmonics? Dumbfounded by how sound gets around? Now you no longer have to struggle to teach concepts you really don t grasp yourself. Sound takes an intentionally light touch to help out all those adults science teachers, parents wanting to help with homework, home-schoolers seeking necessary scientific background to teach middle school physics with confidence. The book introduces sound waves and uses that model to explain sound-related occurrences. Starting with the basics of what causes sound and how it travels, you'll learn how musical instruments work, how sound waves add and subtract, how the human ear works, and even why you can sound like a Munchkin when you inhale helium. Sound is the fourth book in the award-winning Stop Faking It! Series, published by NSTA Press. Like the other popular volumes, it is written by irreverent educator Bill Robertson, who offers this Sound recommendation: One of the coolest activities is whacking a spinning metal rod...

  1. Low-frequency sound exposure causes reversible long-term changes of cochlear transfer characteristics.

    Science.gov (United States)

    Drexl, Markus; Otto, Larissa; Wiegrebe, Lutz; Marquardt, Torsten; Gürkov, Robert; Krause, Eike

    2016-02-01

    Intense, low-frequency sound presented to the mammalian cochlea induces temporary changes of cochlear sensitivity, for which the term 'Bounce' phenomenon has been coined. Typical manifestations are slow oscillations of hearing thresholds or the level of otoacoustic emissions. It has been suggested that these alterations are caused by changes of the mechano-electrical transducer transfer function of outer hair cells (OHCs). Shape estimates of this transfer function can be derived from low-frequency-biased distortion product otoacoustic emissions (DPOAE). Here, we tracked the transfer function estimates before and after triggering a cochlear Bounce. Specifically, cubic DPOAEs, modulated by a low-frequency biasing tone, were followed over time before and after induction of the cochlear Bounce. Most subjects showed slow, biphasic changes of the transfer function estimates after low-frequency sound exposure relative to the preceding control period. Our data show that the operating point changes biphasically on the transfer function with an initial shift away from the inflection point followed by a shift towards the inflection point before returning to baseline values. Changes in transfer function and operating point lasted for about 180 s. Our results are consistent with the hypothesis that intense, low-frequency sound disturbs regulatory mechanisms in OHCs. The homeostatic readjustment of these mechanisms after low-frequency offset is reflected in slow oscillations of the estimated transfer functions. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Preferred sound levels of portable music players and listening habits among adults: a field study.

    Science.gov (United States)

    Kähäri, Kim R; Aslund, T; Olsson, J

    2011-01-01

    The main purpose of this descriptive field study was to explore music listening habits and preferred listening levels with portable music players (PMPs). We were also interested in seeing whether any exposure differences could be observed between the sexes. Data were collected during 12 hours at Stockholm Central Station, where people passing by were invited to measure their preferred PMP listening level by using a KEMAR manikin. People were also asked to answer a questionnaire about their listening habits. In all, 60 persons (41 men and 19 women) took part in the questionnaire study and 61 preferred PMP levels to be measured. Forty-one of these sound level measurements were valid to be reported after consideration was taken to acceptable measuring conditions. The women (31 years) and the men (33 years) started to use PMPs on a regular basis in their early 20s. Ear canal headphones/ear buds were the preferred headphone types. Fifty-seven percent of the whole study population used their PMP on a daily basis. The measured LAeq60 sec levels corrected for free field ranged between 73 and 102 dB, with a mean value of 83 dB. Sound levels for different types of headphones are also presented. The results of this study indicate that there are two groups of listeners: people who listen less frequently and at lower, safer sound levels, and people with excessive listening habits that may indeed damage their hearing sensory organ in time.

  3. Preferred sound levels of portable music players and listening habits among adults: A field study

    Directory of Open Access Journals (Sweden)

    Kim R Kahari

    2011-01-01

    Full Text Available The main purpose of this descriptive field study was to explore music listening habits and preferred listening levels with portable music players (PMPs. We were also interested in seeing whether any exposure differences could be observed between the sexes. Data were collected during 12 hours at Stockholm Central Station, where people passing by were invited to measure their preferred PMP listening level by using a KEMAR manikin. People were also asked to answer a questionnaire about their listening habits. In all, 60 persons (41 men and 19 women took part in the questionnaire study and 61 preferred PMP levels to be measured. Forty-one of these sound level measurements were valid to be reported after consideration was taken to acceptable measuring conditions. The women (31 years and the men (33 years started to use PMPs on a regular basis in their early 20s. Ear canal headphones/ear buds were the preferred headphone types. Fifty-seven percent of the whole study population used their PMP on a daily basis. The measured LAeq60 sec levels corrected for free field ranged between 73 and 102 dB, with a mean value of 83 dB. Sound levels for different types of headphones are also presented. The results of this study indicate that there are two groups of listeners: people who listen less frequently and at lower, safer sound levels, and people with excessive listening habits that may indeed damage their hearing sensory organ in time.

  4. Radiation exposure of airplane crews. Exposure levels

    International Nuclear Information System (INIS)

    Bergau, L.

    1995-01-01

    Even at normal height levels of modern jet airplanes, the flying crew is exposed to a radiation level which is higher by several factors than the terrestrial radiation. There are several ways in which this can be hazardous; the most important of these is the induction of malignant growths, i.e. tumours. (orig./MG) [de

  5. Virtual nature environment with nature sound exposure induce stress recovery by enhanced parasympathetic activity

    DEFF Research Database (Denmark)

    Annerstedt, Matilda; Jönsson, Peter; Wallergård, Mattias

    2013-01-01

    . The group that recovered in virtual nature without sound and the control group displayed no particular autonomic activation or deactivation. The results demonstrate a potential mechanistic link between nature, the sounds of nature, and stress recovery, and suggest the potential importance of virtual reality......Experimental research on stress recovery in natural environments is limited, as is study of the effect of sounds of nature. After inducing stress by means of a virtual stress test, we explored physiological recovery in two different virtual natural environments (with and without exposure to sounds...... of nature) and in one control condition. Cardiovascular data and saliva cortisol were collected. Repeated ANOVA measurements indicated parasympathetic activation in the group subjected to sounds of nature in a virtual natural environment, suggesting enhanced stress recovery may occur in such surroundings...

  6. Sperm whales reduce foraging effort during exposure to 1-2 kHz sonar and killer whale sounds.

    Science.gov (United States)

    Isojunno, Saana; Cure, Charlotte; Kvadsheim, Petter Helgevold; Lam, Frans-Peter Alexander; Tyack, Peter Lloyd; Wensveen, Paul Jacobus; Miller, Patrick James O'Malley

    2016-01-01

    The time and energetic costs of behavioral responses to incidental and experimental sonar exposures, as well as control stimuli, were quantified using hidden state analysis of time series of acoustic and movement data recorded by tags (DTAG) attached to 12 sperm whales (Physeter macrocephalus) using suction cups. Behavioral state transition modeling showed that tagged whales switched to a non-foraging, non-resting state during both experimental transmissions of low-frequency active sonar from an approaching vessel (LFAS; 1-2 kHz, source level 214 dB re 1 µPa m, four tag records) and playbacks of potential predator (killer whale, Orcinus orca) sounds broadcast at naturally occurring sound levels as a positive control from a drifting boat (five tag records). Time spent in foraging states and the probability of prey capture attempts were reduced during these two types of exposures with little change in overall locomotion activity, suggesting an effect on energy intake with no immediate compensation. Whales switched to the active non-foraging state over received sound pressure levels of 131-165 dB re 1 µPa during LFAS exposure. In contrast, no changes in foraging behavior were detected in response to experimental negative controls (no-sonar ship approach or noise control playback) or to experimental medium-frequency active sonar exposures (MFAS; 6-7 kHz, source level 199 re 1 µPa m, received sound pressure level [SPL] = 73-158 dB re 1 µPa). Similarly, there was no reduction in foraging effort for three whales exposed to incidental, unidentified 4.7-5.1 kHz sonar signals received at lower levels (SPL = 89-133 dB re 1 µPa). These results demonstrate that similar to predation risk, exposure to sonar can affect functional behaviors, and indicate that increased perception of risk with higher source level or lower frequency may modulate how sperm whales respond to anthropogenic sound.

  7. Football match spectator sound exposure and effect on hearing: A ...

    African Journals Online (AJOL)

    This was a one-group pretest–post-test design of football spectators attending a premier soccer league match at a designated FIFA 2010 training stadium in Gauteng, South Africa. Individual spectator noise exposure for the duration of the football match and post-match changes in hearing thresholds were measured with ...

  8. A Model for the prediction of Sound Levels within a Symphonic Orchestra based on measured Sound Strength

    NARCIS (Netherlands)

    Wenmaekers, R.H.C.; Hak, C.C.J.M.; Luxemburg, van L.C.J.

    2011-01-01

    Members and directors of symphonic orchestras are concerned about the noise levels musicians are exposed to and their ease of playing ensemble. The results of many research has shown that the noise levels within an orchestra can be high. Also, research has shown that the sound level will vary

  9. Evaluation of the effects of various sound pressure levels on the level of serum aldosterone concentration in rats

    Directory of Open Access Journals (Sweden)

    Parvin Nassiri

    2017-01-01

    Full Text Available Introduction: Noise exposure may have anatomical, nonauditory, and auditory influences. Considering nonauditory impacts, noise exposure can cause alterations in the automatic nervous system, including increased pulse rates, heightened blood pressure, and abnormal secretion of hormones. The present study aimed at examining the effect of various sound pressure levels (SPLs on the serum aldosterone level among rats. Materials and Methods: A total of 45 adult male rats with an age range of 3 to 4 months and a weight of 200 ± 50 g were randomly divided into 15 groups of three. Three groups were considered as the control groups and the rest (i.e., 12 groups as the case groups. Rats of the case groups were exposed to SPLs of 85, 95, and 105 dBA. White noise was used as the noise to which the rats were exposed. To measure the level of rats’ serum aldosterone, 3 mL of each rat’s sample blood was directly taken from the heart of anesthetized animals by using syringes. The taken blood samples were put in labeled test tubes that contained anticoagulant Ethylenediaminetetraacetic acid. In the laboratory, the level of aldosterone was assessed through Enzyme-linked immunosorbent assay protocol. The collected data were analyzed by the use of Statistical Package for Social Sciences (SPSS version 18. Results: The results revealed that there was no significant change in the level of rats’ serum aldosterone as a result of exposure to SPLs of 65, 85, and 95 dBA. However, the level of serum aldosterone experienced a remarkable increase after exposure to the SPL of 105 dBA (P < 0.001. Thus, the SPL had a significant impact on the serum aldosterone level (P < 0.001. In contrast, the exposure time and the level of potassium in the used water did not have any measurable influence on the level of serum aldosterone (P = 0.25 and 0.39. Conclusion: The findings of this study demonstrated that serum aldosterone can be used as a biomarker in the face of sound

  10. The dissimilar time course of temporary threshold shifts and reduction of inhibition in the inferior colliculus following intense sound exposure.

    Science.gov (United States)

    Heeringa, A N; van Dijk, P

    2014-06-01

    Excessive noise exposure is known to produce an auditory threshold shift, which can be permanent or transient in nature. Recent studies showed that noise-induced temporary threshold shifts are associated with loss of synaptic connections to the inner hair cells and with cochlear nerve degeneration, which is reflected in a decreased amplitude of wave I of the auditory brainstem response (ABR). This suggests that, despite normal auditory thresholds, central auditory processing may be abnormal. We recorded changes in central auditory processing following a sound-induced temporary threshold shift. Anesthetized guinea pigs were exposed for 1 h to a pure tone of 11 kHz (124 dB sound pressure level). Hearing thresholds, amplitudes of ABR waves I and IV, and spontaneous and tone-evoked firing rates in the inferior colliculus (IC) were assessed immediately, one week, two weeks, and four weeks post exposure. Hearing thresholds were elevated immediately following overexposure, but recovered within one week. The amplitude of the ABR wave I was decreased in all sound-exposed animals for all test periods. In contrast, the ABR wave IV amplitude was only decreased immediately after overexposure and recovered within a week. The proportion of IC units that show inhibitory responses to pure tones decreased substantially up to two weeks after overexposure, especially when stimulated with high frequencies. The proportion of excitatory responses to low frequencies was increased. Spontaneous activity was unaffected by the overexposure. Despite rapid normalization of auditory thresholds, our results suggest an increased central gain following sound exposure and an abnormal balance between excitatory and inhibitory responses in the midbrain up to two weeks after overexposure. These findings may be associated with hyperacusis after a sound-induced temporary threshold shift. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  11. Can road traffic mask sound from wind turbines? Response to wind turbine sound at different levels of road traffic sound

    NARCIS (Netherlands)

    Pedersen, Eja; van den Berg, Frits; Bakker, Roel; Bouma, Jelte

    Wind turbines are favoured in the switch-over to renewable energy. Suitable sites for further developments could be difficult to find as the sound emitted from the rotor blades calls for a sufficient distance to residents to avoid negative effects. The aim of this study was to explore if road

  12. Hearing loss in relation to sound exposure of professional symphony orchestra musicians

    DEFF Research Database (Denmark)

    Schmidt, J. H.; Pedersen, E. R.; Paarup, H. M.

    2014-01-01

    OBJECTIVES: The objectives of this study were to: (1) estimate the hearing status of classical symphony orchestra musicians and (2) investigate the hypothesis that occupational sound exposure of symphony orchestra musicians leads to elevated hearing thresholds. DESIGN: The study population compri...... that performing music may induce hearing loss to the same extent as industrial noise....

  13. Exposure levels and determinants of inhalable dust exposure in bakeries.

    Science.gov (United States)

    Burstyn, I; Teschke, K; Kennedy, S M

    1997-12-01

    The study's objectives were to measure full-shift exposure to inhalable dust in bakeries and define the determinants of full-shift exposure. Inhalable dust was measured gravimetrically. Ninety-six bakery workers, employed in seven different bakeries, participated in the study. Two side-by-side full-shift inhalable dust samples were obtained from each study participant on a single occasion. Samples were collected on 18 days selected at random. During the entire sampling period, bakers were observed and information on 14 different tasks was recorded at 15 min intervals. Other production characteristics were also recorded for each sampling day. These task and production variables were used in statistical modelling to identify significant predictors of exposure. The mean full-shift inhalable dust exposure was 8.2 mg/m3 (range: 0.1-110 mg/m3). A regression model explained 79% of the variability in exposure. The model indicated that tasks such as weighing, pouring and operating dough-brakers and reversible sheeters increased the exposure, while packing, catching and decorating decreased the exposure. Bread and bun production lines were associated with increased full-shift inhalable dust exposure, while cake production and substitution of dusting with the use of divider oil were associated with decreased exposure. Production tasks and characteristics are strong predictors of personal full-shift exposures to flour dust among bakers; these can be altered to reduce exposure levels.

  14. Prevalence of high frequency hearing loss consistent with noise exposure among people working with sound systems and general population in Brazil: A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Trevisani Virgínia FM

    2008-05-01

    Full Text Available Abstract Background Music is ever present in our daily lives, establishing a link between humans and the arts through the senses and pleasure. Sound technicians are the link between musicians and audiences or consumers. Recently, general concern has arisen regarding occurrences of hearing loss induced by noise from excessively amplified sound-producing activities within leisure and professional environments. Sound technicians' activities expose them to the risk of hearing loss, and consequently put at risk their quality of life, the quality of the musical product and consumers' hearing. The aim of this study was to measure the prevalence of high frequency hearing loss consistent with noise exposure among sound technicians in Brazil and compare this with a control group without occupational noise exposure. Methods This was a cross-sectional study comparing 177 participants in two groups: 82 sound technicians and 95 controls (non-sound technicians. A questionnaire on music listening habits and associated complaints was applied, and data were gathered regarding the professionals' numbers of working hours per day and both groups' hearing complaint and presence of tinnitus. The participants' ear canals were visually inspected using an otoscope. Hearing assessments were performed (tonal and speech audiometry using a portable digital AD 229 E audiometer funded by FAPESP. Results There was no statistically significant difference between the sound technicians and controls regarding age and gender. Thus, the study sample was homogenous and would be unlikely to lead to bias in the results. A statistically significant difference in hearing loss was observed between the groups: 50% among the sound technicians and 10.5% among the controls. The difference could be addressed to high sound levels. Conclusion The sound technicians presented a higher prevalence of high frequency hearing loss consistent with noise exposure than did the general population, although

  15. Brief predator sound exposure elicits behavioral and neuronal long-term sensitization in the olfactory system of an insect

    DEFF Research Database (Denmark)

    Anton, S.; Evengaard, K.; Barrozo, R. B.

    2011-01-01

    later in the same way as exposure to the sex pheromone itself. The observed behavioral modification is accompanied by an increase in the sensitivity of olfactory neurons in the antennal lobe. Our data provide thus evidence for cross-modal experience-dependent plasticity not only on the behavioral level...... at the behavioral and central nervous level. Here we show that this effect is not confined to the same sensory modality: the sensitivity of olfactory neurons can also be modulated by exposure to a different sensory stimulus, i.e., a pulsed stimulus mimicking echolocating sounds from attacking insectivorous bats. We...... tested responses of preexposed male moths in a walking bioassay and recorded from neurons in the primary olfactory center, the antennal lobe. We show that brief exposure to a bat call, but not to a behaviorally irrelevant tone, increases the behavioral sensitivity of male moths to sex pheromone 24 h...

  16. Long-term exposure to noise impairs cortical sound processing and attention control.

    Science.gov (United States)

    Kujala, Teija; Shtyrov, Yury; Winkler, Istvan; Saher, Marieke; Tervaniemi, Mari; Sallinen, Mikael; Teder-Sälejärvi, Wolfgang; Alho, Kimmo; Reinikainen, Kalevi; Näätänen, Risto

    2004-11-01

    Long-term exposure to noise impairs human health, causing pathological changes in the inner ear as well as other anatomical and physiological deficits. Numerous individuals are daily exposed to excessive noise. However, there is a lack of systematic research on the effects of noise on cortical function. Here we report data showing that long-term exposure to noise has a persistent effect on central auditory processing and leads to concurrent behavioral deficits. We found that speech-sound discrimination was impaired in noise-exposed individuals, as indicated by behavioral responses and the mismatch negativity brain response. Furthermore, irrelevant sounds increased the distractibility of the noise-exposed subjects, which was shown by increased interference in task performance and aberrant brain responses. These results demonstrate that long-term exposure to noise has long-lasting detrimental effects on central auditory processing and attention control.

  17. Exterior sound level measurements of snowcoaches at Yellowstone National Park

    Science.gov (United States)

    2010-04-01

    Sounds associated with oversnow vehicles, such as snowmobiles and snowcoaches, are an important management concern at Yellowstone and Grand Teton National Parks. The John A. Volpe National Transportation Systems Centers Environmental Measurement a...

  18. The importance of ambient sound level to characterise anuran habitat.

    Directory of Open Access Journals (Sweden)

    Sandra Goutte

    Full Text Available Habitat characterisation is a pivotal step of any animal ecology study. The choice of variables used to describe habitats is crucial and need to be relevant to the ecology and behaviour of the species, in order to reflect biologically meaningful distribution patterns. In many species, acoustic communication is critical to individuals' interactions, and it is expected that ambient acoustic conditions impact their local distribution. Yet, classic animal ecology rarely integrates an acoustic dimension in habitat descriptions. Here we show that ambient sound pressure level (SPL is a strong predictor of calling site selection in acoustically active frog species. In comparison to six other habitat-related variables (i.e. air and water temperature, depth, width and slope of the stream, substrate, SPL had the most important explanatory power in microhabitat selection for the 34 sampled species. Ambient noise was particularly useful in differentiating two stream-associated guilds: torrents and calmer streams dwelling species. Guild definitions were strongly supported by SPL, whereas slope, which is commonly used in stream-associated habitat, had a weak explanatory power. Moreover, slope measures are non-standardized across studies and are difficult to assess at small scale. We argue that including an acoustic descriptor will improve habitat-species analyses for many acoustically active taxa. SPL integrates habitat topology and temporal information (such as weather and hour of the day, for example and is a simple and precise measure. We suggest that habitat description in animal ecology should include an acoustic measure such as noise level because it may explain previously misunderstood distribution patterns.

  19. L-type calcium channels refine the neural population code of sound level

    Science.gov (United States)

    Grimsley, Calum Alex; Green, David Brian

    2016-01-01

    The coding of sound level by ensembles of neurons improves the accuracy with which listeners identify how loud a sound is. In the auditory system, the rate at which neurons fire in response to changes in sound level is shaped by local networks. Voltage-gated conductances alter local output by regulating neuronal firing, but their role in modulating responses to sound level is unclear. We tested the effects of L-type calcium channels (CaL: CaV1.1–1.4) on sound-level coding in the central nucleus of the inferior colliculus (ICC) in the auditory midbrain. We characterized the contribution of CaL to the total calcium current in brain slices and then examined its effects on rate-level functions (RLFs) in vivo using single-unit recordings in awake mice. CaL is a high-threshold current and comprises ∼50% of the total calcium current in ICC neurons. In vivo, CaL activates at sound levels that evoke high firing rates. In RLFs that increase monotonically with sound level, CaL boosts spike rates at high sound levels and increases the maximum firing rate achieved. In different populations of RLFs that change nonmonotonically with sound level, CaL either suppresses or enhances firing at sound levels that evoke maximum firing. CaL multiplies the gain of monotonic RLFs with dynamic range and divides the gain of nonmonotonic RLFs with the width of the RLF. These results suggest that a single broad class of calcium channels activates enhancing and suppressing local circuits to regulate the sensitivity of neuronal populations to sound level. PMID:27605536

  20. A Loudness Function for Maintaining Spectral Balance at Changing Sound Pressure Levels

    DEFF Research Database (Denmark)

    Nielsen, Sofus Birkedal

    Our perception of loudness is a function of frequency as well as sound pressure level as described in ISO226:2003: Normal Equal Loudness Level Contours, which describes the needed sound pressure level for pure tones to be perceived equally loud. At a music performance, this is taking care...... of by the sound engineer by listening to the individual sound sources and adjust and equalize them to the wanted spectral balance including the whole chain of audio equipment and surroundings. At a live venue the sound pressure level will normally change during a concert, and typically increase over time......B is doubling of the effect to the loudspeakers). A level depending digital loudness function has been made based on ISO226:2003, and will be demonstrated. It can maintain the spectral balance at alternating levels and is based on fractional order digital filters. Tutorial. Abstract T3.3 (30th August 16:00 - 17...

  1. The Influence of Neonatal Intensive Care Unit Design on Sound Level

    Directory of Open Access Journals (Sweden)

    Hsin-Li Chen

    2009-12-01

    Conclusion: The sound level measured in the enclosed space was quieter than in the open space. The design of bed space should be taken into consideration when building a new NICU. Besides the design of NICU architecture, continuous monitoring of sound level in the NICU is important to maintain a quiet environment.

  2. Sound and sound sources

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Wahlberg, Magnus

    2017-01-01

    There is no difference in principle between the infrasonic and ultrasonic sounds, which are inaudible to humans (or other animals) and the sounds that we can hear. In all cases, sound is a wave of pressure and particle oscillations propagating through an elastic medium, such as air. This chapter...... is about the physical laws that govern how animals produce sound signals and how physical principles determine the signals’ frequency content and sound level, the nature of the sound field (sound pressure versus particle vibrations) as well as directional properties of the emitted signal. Many...... of these properties are dictated by simple physical relationships between the size of the sound emitter and the wavelength of emitted sound. The wavelengths of the signals need to be sufficiently short in relation to the size of the emitter to allow for the efficient production of propagating sound pressure waves...

  3. Sound exposure by personal stereo, field study of young people in Denmark

    DEFF Research Database (Denmark)

    Ordoñez, Rodrigo Pizarro; Reuter, Karen; Hammershøi, Dorte

    2006-01-01

    A number of large scale studies suggest that the exposure level used with personal stereo systems should raise concern. It has been demonstrated that 1) high levels can be produced, 2) high levels are used, especially in situations with high background noise, 3) exposure levels are comparables...... with that of industrial noise exposure. In the present study, measurements of the everyday exposure levels will be measured according to principles of ISO 11904-2:2004 for students at various school levels. The measurements will be accompanied with questionnaire detailing the individual habits of use, and with assessment...... of hearing levels and OAE....

  4. Human exposure to low level ionising radiation

    International Nuclear Information System (INIS)

    Paix, David

    1988-01-01

    This paper describes the low-level radiation sources and their effects on human populations, from a global perspective. 'Low-level' means exposures in the range of the natural background to which everybody is exposed. The quoted values are whole-world averages, but individual variations are mentioned in a few cases. (author). 22 refs

  5. How male sound pressure level influences phonotaxis in virgin female Jamaican field crickets (Gryllus assimilis

    Directory of Open Access Journals (Sweden)

    Karen Pacheco

    2014-06-01

    Full Text Available Understanding female mate preference is important for determining the strength and direction of sexual trait evolution. The sound pressure level (SPL acoustic signalers use is often an important predictor of mating success because higher sound pressure levels are detectable at greater distances. If females are more attracted to signals produced at higher sound pressure levels, then the potential fitness impacts of signalling at higher sound pressure levels should be elevated beyond what would be expected from detection distance alone. Here we manipulated the sound pressure level of cricket mate attraction signals to determine how female phonotaxis was influenced. We examined female phonotaxis using two common experimental methods: spherical treadmills and open arenas. Both methods showed similar results, with females exhibiting greatest phonotaxis towards loud sound pressure levels relative to the standard signal (69 vs. 60 dB SPL but showing reduced phonotaxis towards very loud sound pressure level signals relative to the standard (77 vs. 60 dB SPL. Reduced female phonotaxis towards supernormal stimuli may signify an acoustic startle response, an absence of other required sensory cues, or perceived increases in predation risk.

  6. Hearing Tests on Mobile Devices: Evaluation of the Reference Sound Level by Means of Biological Calibration.

    Science.gov (United States)

    Masalski, Marcin; Kipiński, Lech; Grysiński, Tomasz; Kręcicki, Tomasz

    2016-05-30

    Hearing tests carried out in home setting by means of mobile devices require previous calibration of the reference sound level. Mobile devices with bundled headphones create a possibility of applying the predefined level for a particular model as an alternative to calibrating each device separately. The objective of this study was to determine the reference sound level for sets composed of a mobile device and bundled headphones. Reference sound levels for Android-based mobile devices were determined using an open access mobile phone app by means of biological calibration, that is, in relation to the normal-hearing threshold. The examinations were conducted in 2 groups: an uncontrolled and a controlled one. In the uncontrolled group, the fully automated self-measurements were carried out in home conditions by 18- to 35-year-old subjects, without prior hearing problems, recruited online. Calibration was conducted as a preliminary step in preparation for further examination. In the controlled group, audiologist-assisted examinations were performed in a sound booth, on normal-hearing subjects verified through pure-tone audiometry, recruited offline from among the workers and patients of the clinic. In both the groups, the reference sound levels were determined on a subject's mobile device using the Bekesy audiometry. The reference sound levels were compared between the groups. Intramodel and intermodel analyses were carried out as well. In the uncontrolled group, 8988 calibrations were conducted on 8620 different devices representing 2040 models. In the controlled group, 158 calibrations (test and retest) were conducted on 79 devices representing 50 models. Result analysis was performed for 10 most frequently used models in both the groups. The difference in reference sound levels between uncontrolled and controlled groups was 1.50 dB (SD 4.42). The mean SD of the reference sound level determined for devices within the same model was 4.03 dB (95% CI 3

  7. Ultrastructural damage of Loligo vulgaris and Illex coindetii statocysts after low frequency sound exposure.

    Directory of Open Access Journals (Sweden)

    Marta Solé

    Full Text Available There is a considerable lack of information concerning marine invertebrate sensitivity to sound exposure. However, recent findings on cuttlefish and octopi showed that exposure to artificial noise had a direct consequence on the functionality and physiology of the statocysts, sensory organs, which are responsible for their equilibrium and movements in the water column. Owing to a lack of available data on deep diving cephalopod species, we conducted a noise exposure comparative experiment on one Mediterranean squid, Illex coindetii, and on the European squid Loligo vulgaris. Scanning electron microscopy (SEM revealed similar injuries in the inner structure of the statocysts, as those found in cuttlefish and octopi. In addition to the ultrastructural description of the lesions, we publish here the first images of the crista-cupula system and inner statocyst cavity of I. coindetii.

  8. Effect of gentamicin and levels of ambient sound on hearing screening outcomes in the neonatal intensive care unit: A pilot study.

    Science.gov (United States)

    Garinis, Angela C; Liao, Selena; Cross, Campbell P; Galati, Johnathan; Middaugh, Jessica L; Mace, Jess C; Wood, Anna-Marie; McEvoy, Lindsey; Moneta, Lauren; Lubianski, Troy; Coopersmith, Noe; Vigo, Nicholas; Hart, Christopher; Riddle, Artur; Ettinger, Olivia; Nold, Casey; Durham, Heather; MacArthur, Carol; McEvoy, Cynthia; Steyger, Peter S

    2017-06-01

    Hearing loss rates in infants admitted to neonatal intensive care units (NICU) run at 2-15%, compared to 0.3% in full-term births. The etiology of this difference remains poorly understood. We examined whether the level of ambient sound and/or cumulative gentamicin (an aminoglycoside) exposure affect NICU hearing screening results, as either exposure can cause acquired, permanent hearing loss. We hypothesized that higher levels of ambient sound in the NICU, and/or gentamicin dosing, increase the risk of referral on the distortion product otoacoustic emission (DPOAE) assessments and/or automated auditory brainstem response (AABR) screens. This was a prospective pilot outcomes study of 82 infants (4172 Hz) was 44%. DPOAE referrals were significantly greater for infants receiving >2 days of gentamicin dosing compared to fewer doses (p = 0.004). The effect of sound exposure and gentamicin treatment on hearing could not be determined due to the low number of NICU infants without gentamicin exposure (for control comparisons). All infants were exposed to higher levels of ambient sound that substantially exceed AAP guidelines. More referrals were generated by DPOAE assessments than with AABR screens, with significantly more DPOAE referrals with a high-frequency F2 range, consistent with sound- and/or gentamicin-induced cochlear dysfunction. Adding higher frequency DPOAE assessments to existing NICU hearing screening protocols could better identify infants at-risk for ototoxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. A noisy spring: the impact of globally rising underwater sound levels on fish.

    Science.gov (United States)

    Slabbekoorn, Hans; Bouton, Niels; van Opzeeland, Ilse; Coers, Aukje; ten Cate, Carel; Popper, Arthur N

    2010-07-01

    The underwater environment is filled with biotic and abiotic sounds, many of which can be important for the survival and reproduction of fish. Over the last century, human activities in and near the water have increasingly added artificial sounds to this environment. Very loud sounds of relatively short exposure, such as those produced during pile driving, can harm nearby fish. However, more moderate underwater noises of longer duration, such as those produced by vessels, could potentially impact much larger areas, and involve much larger numbers of fish. Here we call attention to the urgent need to study the role of sound in the lives of fish and to develop a better understanding of the ecological impact of anthropogenic noise. Copyright 2010 Elsevier Ltd. All rights reserved.

  10. In situ mortality experiments with juvenile sea bass (Dicentrarchus labrax in relation to impulsive sound levels caused by pile driving of windmill foundations.

    Directory of Open Access Journals (Sweden)

    Elisabeth Debusschere

    Full Text Available Impact assessments of offshore wind farm installations and operations on the marine fauna are performed in many countries. Yet, only limited quantitative data on the physiological impact of impulsive sounds on (juvenile fishes during pile driving of offshore wind farm foundations are available. Our current knowledge on fish injury and mortality due to pile driving is mainly based on laboratory experiments, in which high-intensity pile driving sounds are generated inside acoustic chambers. To validate these lab results, an in situ field experiment was carried out on board of a pile driving vessel. Juvenile European sea bass (Dicentrarchus labrax of 68 and 115 days post hatching were exposed to pile-driving sounds as close as 45 m from the actual pile driving activity. Fish were exposed to strikes with a sound exposure level between 181 and 188 dB re 1 µPa².s. The number of strikes ranged from 1739 to 3067, resulting in a cumulative sound exposure level between 215 and 222 dB re 1 µPa².s. Control treatments consisted of fish not exposed to pile driving sounds. No differences in immediate mortality were found between exposed and control fish groups. Also no differences were noted in the delayed mortality up to 14 days after exposure between both groups. Our in situ experiments largely confirm the mortality results of the lab experiments found in other studies.

  11. Modulation of the sound press level by the treatment of polymer diaphragms through ion implantation method

    International Nuclear Information System (INIS)

    Yeo, Sunmog; Park, Jaewon; Lee, Hojae

    2010-01-01

    We present two different surface modification treatments, an ion implantation, and an ion beam mixing, and show that the surface modifications caused by these treatments are useful tools to modulate the sound press level. The ion implantations on various polymer diaphragms cause an increase in the resonant frequency so that the sound press level is lowered at low frequencies. On the contrary, a Cu or Fe 2 O 3 coating by using an ion beam mixing method causes a decrease in the resonant frequency, resulting in a high sound press level at low frequencies. We discuss the physical reasons for the change in the sound press level due to the ion-implantation methods.

  12. The influence of neonatal intensive care unit design on sound level.

    Science.gov (United States)

    Chen, Hsin-Li; Chen, Chao-Huei; Wu, Chih-Chao; Huang, Hsiu-Jung; Wang, Teh-Ming; Hsu, Chia-Chi

    2009-12-01

    Excessive noise in nurseries has been found to cause adverse effects in infants, especially preterm infants in neonatal intensive care units (NICUs). The NICU design may influence the background sound level. We compared the sound level in two differently designed spaces in one NICU. We hypothesized that the sound level in an enclosed space would be quieter than in an open space. Sound levels were measured continuously 24 hours a day in two separate spaces at the same time, one enclosed and one open. Sound-level meters were placed near beds in each room. Sound levels were expressed as decibels, A-weighted (dBA) and presented as hourly L(eq), L(max), L(10), and L(90). The hourly L(eq) in the open space (50.8-57.2dB) was greater than that of the enclosed space (45.9-51.7dB), with a difference of 0.4-10.4dB, and a mean difference of 4.5dB (p<0.0001). The hourly L(10), L(90), and L(max) in the open space also exceeded that in the enclosed space (p<0.0001). The sound level measured in the enclosed space was quieter than in the open space. The design of bed space should be taken into consideration when building a new NICU. Besides the design of NICU architecture, continuous monitoring of sound level in the NICU is important to maintain a quiet environment.

  13. A study investigating sound sources and noise levels in neonatal ...

    African Journals Online (AJOL)

    Background. Exposure to noise in the neonatal intensive care unit (NICU) has the potential to affect neonatal auditory development, sleep patterns and physiological stability, thus impacting on developmental progress. Objectives. This study aimed to identify noise sources in three NICUs in Johannesburg, South Africa, and ...

  14. Emergency exposure levels for natural uranium

    International Nuclear Information System (INIS)

    Spoor, N.L.; Harrison, N.T.

    1980-12-01

    An attempt is made to identify the inhalation hazards associated with the over-exposure of workers and of the general public, following an accidental release of uranium hexafluoride. Maximum emergency concentrations are recommended for periods of 10, 30, and 60 minutes. The quantitative aspect of the assessment is considered in the context of the development of exposure standards for chemical substances and this facilitates the derivation of levels which are compatible with occupational and public health experience and attainable by management, and to which most workers and members of the general public may be exposed without adverse effect. The radiological implications are also considered. (author)

  15. Sound production in Japanese medaka (Oryzias latipes) and its alteration by exposure to aldicarb and copper sulfate.

    Science.gov (United States)

    Kang, Ik Joon; Qiu, Xuchun; Moroishi, Junya; Oshima, Yuji

    2017-08-01

    This study is the first to report sound production in Japanese medaka (Oryzias latipes). Sound production was affected by exposure to the carbamate insecticide (aldicarb) and heavy-metal compound (copper sulfate). Medaka were exposed at four concentrations (aldicarb: 0, 0.25, 0.5, and 1 mg L -1 ; copper sulfate: 0, 0.5, 1, and 2 mg L -1 ), and sound characteristics were monitored for 5 h after exposure. We observed constant average interpulse intervals (approx 0.2 s) in all test groups before exposure, and in the control groups throughout the experiment. The average interpulse interval became significantly longer during the recording periods after 50 min of exposure to aldicarb, and reached a length of more than 0.3 s during the recording periods after 120 min exposure. Most medaka fish stopped to produce sound after 50 min of exposure to copper sulfate at 1 and 2 mg L -1 , resulting in significantly declined number of sound pulses and pulse groups. Relative shortened interpulse intervals of sound were occasionally observed in medaka fish exposed to 0.5 mg L -1 copper sulfate. These alternations in sound characteristics due to toxicants exposure suggested that they might impair acoustic communication of medaka fish, which may be important for their reproduction and survival. Our results suggested that using acoustic changes of medaka has potential to monitor precipitate water pollutions, such as intentional poisoning or accidental leakage of industrial waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Dose level of occupational exposure in China

    International Nuclear Information System (INIS)

    Tian, Y.; Zhang, L.; Ju, Y.

    2008-01-01

    This paper discusses the dose level of Chinese occupational exposures during 1986-2000. Data on occupational exposures from the main categories in nuclear fuel cycle (uranium enrichment and conversion, fuel fabrication, reactor operation, waste management and research activity, except for uranium mining and milling because of the lack of data), medical uses of radiation (diagnostic radiation, nuclear medicine and radiotherapy) and industrial uses of radiation (industrial radiography and radioisotope production) are presented and summarised in detail. These are the main components of occupational exposures in China. In general, the average annual effective doses show a steady decreasing trend over periods: from 2.16 to 1.16 mSv in medical uses of radiation during 1990-2000; from 1.92 to 1.18 mSv in industrial radiography during 1990-2000; from 8.79 to 2.05 mSv in radioisotope production during the period 1980-2000. Almost all the average annual effective doses in discussed occupations were lower than 5 mSv in recent years (except for well-logging: 6.86 mSv in 1999) and no monitored workers were found to have received the occupational exposure exceeding 50 mSv in a single year or 100 mSv in a five-year period. So the Chinese protection status of occupation exposure has been improved in recent years. However, the average annual effective doses in some occupations, such as diagnostic radiology and coal mining, were still much higher than that of the whole world. There are still needs for further improvement and careful monitoring of occupational exposure to protect every worker from excessive occupational exposure, especially for the workers who were neglected before. (authors)

  17. HELLE: Health Effects of Low Level Exposures

    International Nuclear Information System (INIS)

    Schoten, Eert

    1998-01-01

    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

  18. Emergence of category-level sensitivities in non-native speech sound learning

    Directory of Open Access Journals (Sweden)

    Emily eMyers

    2014-08-01

    Full Text Available Over the course of development, speech sounds that are contrastive in one’s native language tend to become perceived categorically: that is, listeners are unaware of variation within phonetic categories while showing excellent sensitivity to speech sounds that span linguistically meaningful phonetic category boundaries. The end stage of this developmental process is that the perceptual systems that handle acoustic-phonetic information show special tuning to native language contrasts, and as such, category-level information appears to be present at even fairly low levels of the neural processing stream. Research on adults acquiring non-native speech categories offers an avenue for investigating the interplay of category-level information and perceptual sensitivities to these sounds as speech categories emerge. In particular, one can observe the neural changes that unfold as listeners learn not only to perceive acoustic distinctions that mark non-native speech sound contrasts, but also to map these distinctions onto category-level representations. An emergent literature on the neural basis of novel and non-native speech sound learning offers new insight into this question. In this review, I will examine this literature in order to answer two key questions. First, where in the neural pathway does sensitivity to category-level phonetic information first emerge over the trajectory of speech sound learning? Second, how do frontal and temporal brain areas work in concert over the course of non-native speech sound learning? Finally, in the context of this literature I will describe a model of speech sound learning in which rapidly-adapting access to categorical information in the frontal lobes modulates the sensitivity of stable, slowly-adapting responses in the temporal lobes.

  19. Sound levels in a neonatal intensive care unit significantly exceeded recommendations, especially inside incubators.

    Science.gov (United States)

    Parra, Johanna; de Suremain, Aurelie; Berne Audeoud, Frederique; Ego, Anne; Debillon, Thierry

    2017-12-01

    This study measured sound levels in a 2008 built French neonatal intensive care unit (NICU) and compared them to the 2007 American Academy of Pediatrics (AAP) recommendations. The ultimate aim was to identify factors that could influence noise levels. The study measured sound in 17 single or double rooms in the NICU. Two dosimeters were installed in each room, one inside and one outside the incubators, and these conducted measurements over a 24-hour period. The noise metrics measured were the equivalent continuous sound level (L eq ), the maximum noise level (L max ) and the noise level exceeded for 10% of the measurement period (L 10 ). The mean L eq , L 10 and L max were 60.4, 62.1 and 89.1 decibels (dBA), which exceeded the recommended levels of 45, 50 and 65 dBA (p care was correlated to an increased noise level, except for a postconceptional age below 32 weeks. The sound levels significantly exceeded the AAP recommendations, particularly inside incubators. A multipronged strategy is required to improve the sound environment and protect the neonates' sensory development. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  20. Detection System of Sound Noise Level (SNL) Based on Condenser Microphone Sensor

    Science.gov (United States)

    Rajagukguk, Juniastel; Eka Sari, Nurdieni

    2018-03-01

    The research aims to know the noise level by using the Arduino Uno as data processing input from sensors and called as Sound Noise Level (SNL). The working principle of the instrument is as noise detector with the show notifications the noise level on the LCD indicator and in the audiovisual form. Noise detection using the sensor is a condenser microphone and LM 567 as IC op-amps, which are assembled so that it can detect the noise, which sounds are captured by the sensor will turn the tide of sinusoida voice became sine wave energy electricity (altering sinusoida electric current) that is able to responded to complaints by the Arduino Uno. The tool is equipped with a detector consists of a set indicator LED and sound well as the notification from the text on LCD 16*2. Work setting indicators on the condition that, if the measured noise > 75 dB then sound will beep, the red LED will light up indicating the status of the danger. If the measured value on the LCD is higher than 56 dB, sound indicator will be beep and yellow LED will be on indicating noisy. If the noise measured value <55 dB, sound indicator will be quiet indicating peaceful from noisy. From the result of the research can be explained that the SNL is capable to detecting and displaying noise level with a measuring range 50-100 dB and capable to delivering the notification noise in audiovisual.

  1. Artificial Heads for High-Level Impulse Sound Measurement

    National Research Council Canada - National Science Library

    Buck, K

    1999-01-01

    If the Insertion Loss (IL) of hearing protectors has to be determined with very high impulse or continuous noise levels, the acoustic insulation of the Artificial Test Fixture has to exceed at least the Insertion Loss (IL...

  2. Assessing the Health of Puget Sound's Pelagic Food Web at Multiple Trophic Levels

    Science.gov (United States)

    Rhodes, L. D.; Greene, C. M.; Rice, C. A.; Hall, J. E.; Baxter, A. E.; Naman, S. M.; Chamberlin, J.

    2012-12-01

    Puget Sound is an estuarine fjord in the northwestern United State surrounded by variable upland uses, ranging from industrial and urban to agricultural to forested lands. The quality of Puget Sound's ecosystem is under scrutiny because of the biological resources that depend on its function. In 2011, we undertook a study of the Sound's pelagic food web that measured water quality, microbial parameters, and abundance of higher trophic levels including gelatinous zooplankton, forage fish, and salmon. More than 75 sites spanning the latitudinal expanse of Puget Sound and the range of developed and agricultural land uses were sampled monthly from April to October. Strong relationships between water quality and microbial parameters suggest that microbes may modulate water quality indicators, such as dissolved inorganic nitrogen and pH, and that land use may be an influential factor. Basins within Puget Sound exhibit distinct biological profiles at the microbial and macrobiotic levels, emphasizing that Puget Sound is not a homogenous water body and suggesting that informative food web indicators may vary across the basins.

  3. Simultaneous reflection masking: dependency on direct sound level and hearing-impairment

    DEFF Research Database (Denmark)

    Buchholz, Jörg; Mihai, Paul Glad

    2008-01-01

    B-SL direct sound level, NH-listeners showed a binaural suppression effect for delays smaller than 7-10 ms and a binaural enhancement effect for larger delays. When decreasing the direct sound level to 15 dB-SL, the only significant change observed was that the dichotic RMT increased for delays larger than...... expected from changed auditory filter bandwidth and audi-bility. However, the stimulus level-dependency of the auditory filters’ bandwidth was not reflected in the SRMT data....

  4. Low sound level source path contribution on a HVAC

    NARCIS (Netherlands)

    Bree, H.E. de; Basten, T.G.H.

    2008-01-01

    For compliance test purposes, the noise level of a HVAC is usually measured with a pressure microphone positioned at a certain distance. This measurement is normally performed in an anechoic room. However, this method doesn't provide the engineer any insight on what noise sources do contribute to

  5. Tutorial and Guidelines on Measurement of Sound Pressure Level in Voice and Speech

    Science.gov (United States)

    Švec, Jan G.; Granqvist, Svante

    2018-01-01

    Purpose: Sound pressure level (SPL) measurement of voice and speech is often considered a trivial matter, but the measured levels are often reported incorrectly or incompletely, making them difficult to compare among various studies. This article aims at explaining the fundamental principles behind these measurements and providing guidelines to…

  6. 30 CFR 62.130 - Permissible exposure level.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Permissible exposure level. 62.130 Section 62... REGULATIONS OCCUPATIONAL NOISE EXPOSURE § 62.130 Permissible exposure level. (a) The mine operator must assure that no miner is exposed during any work shift to noise that exceeds the permissible exposure level. If...

  7. CURRENT LEVELS OF MEDICAL EXPOSURE IN RUSSIA

    Directory of Open Access Journals (Sweden)

    M. I. Balonov

    2015-01-01

    Full Text Available We considered conditions of patients’ medical radiation exposure in Russian diagnostic radiology and nuclear medicine basing on the data of our own research, of the Unified system of individual dose control and of some relevant literature. We analyzed the data on the number of diagnostic examinations, patients’ individual and collective doses and their distribution by examination types. Time trends of the studied parameters are presented for the period between 1999 and 2013. Current level of Russian patients’ medical exposure is the lowest over the whole observation period and one of the lowest among the developed countries. The annual number of X-ray diagnostic examinations is 1.8 per capita. In 2013 median effective dose of medical exposure per capita in Russia was 0.45 mSv and median dose per procedure was 0.25 mSv. The major contribution to collective dose of medical exposure was from computed tomography and radiography; the largest individual doses were caused by interventional radiology, computed X-Ray and nuclear medicine tomographic examinations. The range of median doses comprises about four orders of magnitude, i.e. from several microSv in dental X-ray examinations up to several tens of milliSv in interventional and multistage tomographic examinations. The median effective dose of adult patients increases by about an order of magnitude with each transition from dental X-ray examinations to conventional radiology and further to computed tomography and interventional radiology examinations. During interventional X-Ray examinations, absorbed skin doses at radiation beam entrance site may reach several Gray, which may lead to deterministic radiation effects in skin and subcutaneous tissues. Due to replacement of low-dose ‘functional’ nuclear medicine examinations with more informative modern scintigraphy and tomography examination, patient doses substantially increased over the last decade. With current trend for re-equipment of

  8. Equivalent threshold sound pressure levels (ETSPL) for Interacoustics DD 45 supra-aural audiometric earphones

    DEFF Research Database (Denmark)

    Poulsen, Torben

    2010-01-01

    This paper describes the determination and results of pure tone Equivalent Threshold Sound Pressure Levels for the Interacoustics DD45 audiometric earphone equipped with standard Model 51 cushions. The size and shape of the DD45 transducer resembles the classical Telephonics TDH 39 earphone. Pure...... tone hearing threshold measurements were performed for both ears of 29 test subjects. All audiometric frequencies from 125 Hz to 8 kHz were used. The data are intended for inclusion in future standardized Reference Equivalent Threshold Sound Pressure Levels. The results show that the DD45 may be a good...

  9. Pressure sound level measurements at an educational environment in Goiania, Goias, Brazil

    International Nuclear Information System (INIS)

    Costa, Jhonatha J.L.; Nascimento, Eriberto O. do; Oliveira, Lucas N. de; Caldas, Linda V. E.

    2017-01-01

    In this work, twenty five points located on the ground floor of the Federal Institute of Education, Science and Technology of Goias - IFG - Campus Goiania, were analyzed in morning periods of two Saturdays. The pressure sound levels were measured at internal and external environments during routine activities seeking to perform an environmental monitoring at this institution. The initial hypothesis was that an amusement park (Mutirama Park) was responsible for originating noise pollution in the institution, but the results showed, within the campus environment, sound pressure levels in accordance with the Municipal legislation of Goiania for all points. (author)

  10. Pressure sound level measurements at an educational environment in Goiania, Goias, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Jhonatha J.L.; Nascimento, Eriberto O. do; Oliveira, Lucas N. de [Instituto Federal de Educação, Ciência e Tecnologia de Goiás (IFG), Goiânia, GO (Brazil); Caldas, Linda V. E., E-mail: lcaldas@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    In this work, twenty five points located on the ground floor of the Federal Institute of Education, Science and Technology of Goias - IFG - Campus Goiania, were analyzed in morning periods of two Saturdays. The pressure sound levels were measured at internal and external environments during routine activities seeking to perform an environmental monitoring at this institution. The initial hypothesis was that an amusement park (Mutirama Park) was responsible for originating noise pollution in the institution, but the results showed, within the campus environment, sound pressure levels in accordance with the Municipal legislation of Goiania for all points. (author)

  11. Exposure to unusually high indoor radon levels

    International Nuclear Information System (INIS)

    Rasheed, F.N.

    1993-01-01

    Unusually high indoor radon concentrations were reported in a small village in western Tyrol, Austria. The authors have measured the seasonal course of indoor radon concentrations in 390 houses of this village. 71% of houses in winter and 33% in summer, showed radon values on the ground floor above the Austrian action level of 400 Bq/cm 3 . This proportion results in an unusually high indoor radon exposure of the population. The radon source was an 8,700-year-old rock slide of granite gneiss, the largest of the alpine crystalline rocks. It has a strong emanating power because its rocks are heavily fractured and show a slightly increased uranium content. Previous reports show increased lung cancer mortality, myeloid leukemia, kidney cancer, melanoma, and prostate cancer resulting from indoor radon exposure. However, many studies fail to provide accurate information on indoor radon concentrations, classifying them merely as low, intermediate, and high, or they record only minor increases in indoor radon concentrations. Mortality data for 1970-91 were used to calculate age and sex standardized mortality rates (SMR) for 51 sites of carcinoma. The total population of Tyrol were controls. A significantly higher risk was recorded for lung cancer. The high SMR for lung cancer in female subjects is especially striking. Because the numbers were low for the other cancer sites, these were combined in one group to calculate the SMR. No significant increase in SMR was found for this group

  12. Equivalent threshold sound pressure levels for acoustic test signals of short duration

    DEFF Research Database (Denmark)

    Poulsen, Torben; Daugaard, Carsten

    1998-01-01

    . The measurements were performed with two types of headphones, Telephonics TDH-39 and Sennheiser HDA-200. The sound pressure levels were measured in an IEC 318 ear simulator with Type 1 adapter (a flat plate) and a conical ring. The audiometric methods used in the experiments were the ascending method (ISO 8253...

  13. [Sound levels of the Piezosurgery. Risk of permanent damage to hearing

    NARCIS (Netherlands)

    Blakenburg, J.J.; Both, C.J.; Borstlap, W.A.; Damme, P.A. van

    2007-01-01

    In the past, research has regularly been carried out concerning the sound levels of various drilling devices and the impact these have on those who regularly use these devices. The present research is concerned with the possible permanent damage to hearing which can occur during the use of a newly

  14. Estimation of sound pressure levels of voiced speech from skin vibration of the neck

    NARCIS (Netherlands)

    Svec, JG; Titze, IR; Popolo, PS

    How accurately can sound pressure levels (SPLs) of speech be estimated from skin vibration of the neck? Measurements using a small accelerometer were carried out in 27 subjects (10 males and 17 females) who read Rainbow and Marvin Williams passages in soft, comfortable, and loud voice, while skin

  15. A sound level distribution model for symphony orchestras: possibilities and limitations

    NARCIS (Netherlands)

    Wenmaekers, R.H.C.; Hak, C.C.J.M.

    2015-01-01

    Musicians in a symphony orchestra rely on the direct and reflected sound on a concert hall stage to be able to hear each other. Besides ensemble conditions, members and directors of symphony orchestras are concerned about the noise levels musicians are exposed to. However, the actual contribution of

  16. A comparison of radiosity with current methods of sound level prediction in commercial spaces

    Science.gov (United States)

    Beamer, C. Walter, IV; Muehleisen, Ralph T.

    2002-11-01

    The ray tracing and image methods (and variations thereof) are widely used for the computation of sound fields in architectural spaces. The ray tracing and image methods are best suited for spaces with mostly specular reflecting surfaces. The radiosity method, a method based on solving a system of energy balance equations, is best applied to spaces with mainly diffusely reflective surfaces. Because very few spaces are either purely specular or purely diffuse, all methods must deal with both types of reflecting surfaces. A comparison of the radiosity method to other methods for the prediction of sound levels in commercial environments is presented. [Work supported by NSF.

  17. Effects of Interaural Level and Time Differences on the Externalization of Sound

    DEFF Research Database (Denmark)

    Dau, Torsten; Catic, Jasmina; Santurette, Sébastien

    Distant sound sources in our environment are perceived as externalized and are thus properly localized in both direction and distance. This is due to the acoustic filtering by the head, torso, and external ears, which provides frequency dependent shaping of binaural cues, such as interaural level...... differences (ILDs) and interaural time differences (ITDs). Further, the binaural cues provided by reverberation in an enclosed space may also contribute to externalization. While these spatial cues are available in their natural form when listening to real-world sound sources, hearing-aid signal processing...... is consistent with the physical analysis that showed that a decreased distance to the sound source also reduced the fluctuations in ILDs....

  18. Transformer sound level caused by core magnetostriction and winding stress displacement variation

    Directory of Open Access Journals (Sweden)

    Chang-Hung Hsu

    2017-05-01

    Full Text Available Magnetostriction caused by the exciting variation of the magnetic core and the current conducted by the winding wired to the core has a significant result impact on a power transformer. This paper presents the sound of a factory transformer before on-site delivery for no-load tests. This paper also discusses the winding characteristics from the transformer full-load tests. The simulation and the measurement for several transformers with capacities ranging from 15 to 60 MVA and high voltage 132kV to low voltage 33 kV are performed. This study compares the sound levels for transformers by no-load test (core/magnetostriction and full-load test (winding/displacement ε. The difference between the simulated and the measured sound levels is about 3dB. The results show that the sound level depends on several parameters, including winding displacement, capacity, mass of the core and windings. Comparative results of magnetic induction of cores and the electromagnetic force of windings for no-load and full-load conditions are examined.

  19. The power of positive and negative expectations to influence reported symptoms and mood during exposure to wind farm sound.

    Science.gov (United States)

    Crichton, Fiona; Dodd, George; Schmid, Gian; Gamble, Greg; Cundy, Tim; Petrie, Keith J

    2014-12-01

    Wind farm developments have been hampered by claims that sound from wind turbines causes symptoms and negative health reports in nearby residents. As scientific reviews have failed to identify a plausible link between wind turbine sound and health effects, psychological expectations have been proposed as an explanation for health complaints. Building on recent work showing negative expectations can create symptoms from wind turbines, we investigated whether positive expectations can produce the opposite effect, in terms of a reduction in symptoms and improvements in reported health. 60 participants were randomized to either positive or negative expectation groups and subsequently exposed to audible wind farm sound and infrasound. Prior to exposure, negative expectation participants watched a DVD incorporating TV footage about health effects said to be caused by infrasound produced by wind turbines. In contrast, positive expectation participants viewed a DVD that outlined the possible therapeutic effects of infrasound exposure. During exposure to audible windfarm sound and infrasound, symptoms and mood were strongly influenced by the type of expectations. Negative expectation participants experienced a significant increase in symptoms and a significant deterioration in mood, while positive expectation participants reported a significant decrease in symptoms and a significant improvement in mood. The study demonstrates that expectations can influence symptom and mood reports in both positive and negative directions. The results suggest that if expectations about infrasound are framed in more neutral or benign ways, then it is likely reports of symptoms or negative effects could be nullified.

  20. Noise levels in neonatal intensive care unit and use of sound absorbing panel in the isolette.

    Science.gov (United States)

    Altuncu, E; Akman, I; Kulekci, S; Akdas, F; Bilgen, H; Ozek, E

    2009-07-01

    The purposes of this study were to measure the noise level of a busy neonatal intensive care unit (NICU) and to determine the effect of sound absorbing panel (SAP) on the level of noise inside the isolette. The sound pressure levels (SPL) of background noise, baby crying, alarms and closing of isolette's door/portholes were measured by a 2235-Brüel&Kjaer Sound Level Meter. Readings were repeated after applying SAP (3D pyramidal shaped open cell polyurethane foam) to the three lateral walls and ceiling of the isolette. The median SPL of background noise inside the NICU was 56dBA and it decreased to 47dBA inside the isolette. The median SPL of monitor alarms and baby crying inside the isolette were not different than SPL measured under radiant warmer (p>0.05). With SAP, the median SPL of temperature alarm inside the isolette decreased significantly from 82 to 72dBA, monitor alarm from 64 to 56dBA, porthole closing from 81 to 74dBA, and isolette door closing from 80 to 68dBA (pnoise produced by baby crying when SAP was used in the isolette (79dBA vs 69dBA, respectively) (pnoise. The noise level in our NICU is significantly above the universally recommended levels. Being inside the isolette protects infants from noise sources produced outside the isolette. However, very high noises are produced inside the isolette as well. Sound absorbing panel can be a simple solution and it attenuated the noise levels inside the isolette.

  1. [Preventive effects of sound insulation windows on the indoor noise levels in a street residential building in Beijing].

    Science.gov (United States)

    Guo, Bin; Huang, Jing; Guo, Xin-biao

    2015-06-18

    To evaluate the preventive effects of sound insulation windows on traffic noise. Indoor noise levels of the residential rooms (on both the North 4th ring road side and the campus side) with closed sound insulation windows were measured using the sound level meter, and comparisons with the simultaneously measured outdoor noise levels were made. In addition, differences of indoor noise levels between rooms with closed sound insulation windows and open sound insulation windows were also compared. The average outdoor noise levels of the North 4th ring road was higher than 70 dB(A), which exceeded the limitation stated in the "Environmental Quality Standard for Noise" (GB 3096-2008) in our country. However, with the sound insulation windows closed, the indoor noise levels reduced significantly to the level under 35 dB(A) (Pwindows had significant influence on the indoor noise levels (Pwindow, when the sound insulation windows were closed, the indoor noise levels reduced 18.8 dB(A) and 8.3 dB(A) in residential rooms facing North 4th ring road side and campus side, respectively. The results indicated that installation of insulation windows had significant noise reduction effects on street residential buildings especially on the rooms facing major traffic roads. Installation of the sound insulation windows has significant preventive effects on indoor noise in the street residential building.

  2. Noise Exposure of Teachers in Nursery Schools-Evaluation of Measures for Noise Reduction When Dropping DUPLO Toy Bricks into Storage Cases by Sound Analyses.

    Science.gov (United States)

    Gebauer, Konstanze; Scharf, Thomas; Baumann, Uwe; Groneberg, David A; Bundschuh, Matthias

    2016-07-04

    Although noise is one of the leading work-related health risk factors for teachers, many nursery schools lack sufficient noise reduction measures. This intervention study evaluated the noise exposure of nursery school teachers when dropping DUPLO toy bricks into storage cases. Sound analyses of the impact included assessment of the maximum sound pressure level (LAFmax) as well as frequency analyses with 1/3 octave band filter. For the purpose of standardization, a customized gadget was developed. Recordings were performed in 11 cases of different materials and designs to assess the impact on sound level reduction. Thereby, the acoustic effects of three damping materials (foam rubber, carpet, and PU-foam) were investigated. The lowest LAFmax was measured in cases consisting of "metal grid" (90.71 dB) or of a woven willow "basket" (91.61 dB), whereas a case of "aluminium" (103.34 dB) generated the highest impact LAFmax. The frequency analyses determined especially low LAFmax in the frequency bands between 80 and 2500 Hz in cases designs "metal grid" and "basket". The insertion of PU-foam achieved the most significant attenuation of LAFmax (-13.88 dB) and, in the frequency analyses, the best sound damping. The dropping of DUPLO bricks in cases contributes to the high noise level in nursery schools, but measured LAFmax show no evidence for the danger of acute hearing loss. However, continuous exposure may lead to functional impairment of the hair cells and trigger stress reactions. We recommend noise reduction by utilizing cases of woven "basket" with an insert of PU-foam.

  3. Noise Exposure of Teachers in Nursery Schools—Evaluation of Measures for Noise Reduction When Dropping DUPLO Toy Bricks into Storage Cases by Sound Analyses

    Directory of Open Access Journals (Sweden)

    Konstanze Gebauer

    2016-07-01

    Full Text Available Background: Although noise is one of the leading work-related health risk factors for teachers, many nursery schools lack sufficient noise reduction measures. Methods: This intervention study evaluated the noise exposure of nursery school teachers when dropping DUPLO toy bricks into storage cases. Sound analyses of the impact included assessment of the maximum sound pressure level (LAFmax as well as frequency analyses with 1/3 octave band filter. For the purpose of standardization, a customized gadget was developed. Recordings were performed in 11 cases of different materials and designs to assess the impact on sound level reduction. Thereby, the acoustic effects of three damping materials (foam rubber, carpet, and PU-foam were investigated. Results: The lowest LAFmax was measured in cases consisting of “metal grid” (90.71 dB or of a woven willow “basket” (91.61 dB, whereas a case of “aluminium” (103.34 dB generated the highest impact LAFmax. The frequency analyses determined especially low LAFmax in the frequency bands between 80 and 2500 Hz in cases designs “metal grid” and “basket”. The insertion of PU-foam achieved the most significant attenuation of LAFmax (−13.88 dB and, in the frequency analyses, the best sound damping. Conclusion: The dropping of DUPLO bricks in cases contributes to the high noise level in nursery schools, but measured LAFmax show no evidence for the danger of acute hearing loss. However, continuous exposure may lead to functional impairment of the hair cells and trigger stress reactions. We recommend noise reduction by utilizing cases of woven “basket” with an insert of PU-foam.

  4. A Loudness Function for Analog and Digital Sound Systems based on Equal Loudness Level Contours

    DEFF Research Database (Denmark)

    Nielsen, Sofus Birkedal

    2016-01-01

    frequency balance will been changed both for LL lower or higher than ML. The differences in ELLC ask for a level based equalization using fractional-order filters. A designing technique for both analog and digital fractional-order filters was developed. The analog solution is based on OPAMs and the digital......A new and better loudness compensation has been designed based on the differences between the Equal Loudness Level Contours (ELLC) in ISO 226:2003. Sound productions are normally being mixed at a high mixing level (ML) but often played at lower listening level (LL) which mean that the perceived...

  5. PERANCANGAN DAN IMPLEMENTASI SOUND LEVEL METER (SLM DALAM SKALA LABORATORIUM SEBAGAI ALAT UKUR INTENSITAS BUNYI

    Directory of Open Access Journals (Sweden)

    Jamaludin .

    2014-09-01

    Full Text Available Laboratory based research is the implementation of Wave Mechanics ( GM . In this physical peristtiwa will be examined on Wave Mechanics in measuring the intensity of sound . In order to determine the relevant SLM using a condenser mic as well as determine the level of noise in the sound of different frequencies in the laboratory scale . Tests carried out under conditions of sound intensity soundproof space and sound intensity comparison with SLM industrial design . In this study also compares the design of the SLM SLM Nor- 118 . So that the data obtained is the result of data collection we did the design of the SLM SLM Nor- 118 can be said to be relevant , but there is a difference is a difference of ± 5.0 % . And at a certain frequency when he would decline due to several internal and external factors . The conclusions drawn are in any retrieval of data must be in the soundproof room so that when the data collection is no factor that affects both external and internal.

  6. Exposure level from selected base station tower around Kuala Nerus

    African Journals Online (AJOL)

    Health risk due to RF radiation exposure from base station tower (BST) has been debated for years leading to public concerns. Thus, this preliminary study aims to measure, evaluate and analyze the exposure level on three selected BST around Kuala Nerus. The measurement of exposure level in terms of voltage ...

  7. Pre-slaughter sound levels and pre-slaughter handling from loading at the farm till slaughter influence pork quality.

    Science.gov (United States)

    Vermeulen, L; Van de Perre, V; Permentier, L; De Bie, S; Verbeke, G; Geers, R

    2016-06-01

    This study investigates the relationship between sound levels, pre-slaughter handling during loading and pork quality. Pre-slaughter variables were investigated from loading till slaughter. A total of 3213 pigs were measured 30 min post-mortem for pH(30LT) (M. Longissimus thoracis). First, a sound level model for the risk to develop PSE meat was established. The difference in maximum and mean sound level during loading, mean sound level during lairage and mean sound level prior to stunning remained significant within the model. This indicated that sound levels during loading had a significant added value to former sound models. Moreover, this study completed the global classification checklist (Vermeulen et al., 2015a) by developing a linear mixed model for pH(30LT) and PSE prevalence, with the difference in maximum and mean sound level measured during loading, the feed withdrawal period and the difference in temperature during loading and lairage. Hence, this study provided new insights over previous research where loading procedures were not included. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. The role of high-level processes for oscillatory phase entrainment to speech sound

    Directory of Open Access Journals (Sweden)

    Benedikt eZoefel

    2015-12-01

    Full Text Available Constantly bombarded with input, the brain has the need to filter out relevant information while ignoring the irrelevant rest. A powerful tool may be represented by neural oscillations which entrain their high-excitability phase to important input while their low-excitability phase attenuates irrelevant information. Indeed, the alignment between brain oscillations and speech improves intelligibility and helps dissociating speakers during a cocktail party. Although well-investigated, the contribution of low- and high-level processes to phase entrainment to speech sound has only recently begun to be understood. Here, we review those findings, and concentrate on three main results: (1 Phase entrainment to speech sound is modulated by attention or predictions, likely supported by top-down signals and indicating higher-level processes involved in the brain’s adjustment to speech. (2 As phase entrainment to speech can be observed without systematic fluctuations in sound amplitude or spectral content, it does not only reflect a passive steady-state ringing of the cochlea, but entails a higher-level process. (3 The role of intelligibility for phase entrainment is debated. Recent results suggest that intelligibility modulates the behavioral consequences of entrainment, rather than directly affecting the strength of entrainment in auditory regions. We conclude that phase entrainment to speech reflects a sophisticated mechanism: Several high-level processes interact to optimally align neural oscillations with predicted events of high relevance, even when they are hidden in a continuous stream of background noise.

  9. ANALYSIS OF SOUND PRESSURE LEVEL (SPL AND LAY OUT OF ENGINES IN THE FACTORY

    Directory of Open Access Journals (Sweden)

    Wijianto Wijianto

    2017-01-01

    Full Text Available Modeling layout of engines in the factory is very useful to know how many dB sound pressure level that are occur in the building in order to avoid hearing damage of employees that are caused by noise. The objective of this research is to know how many dB sound pressure level that are occur in the factory with engine composition such as boiler, diesel, turbine, motor and gear box with dimension of building are 40 m length, 35 m width and 10 m height. With MATLAB analysis can be obtain that the highest SPL is 104.7 dB and the lowest is 93.5 dB, so, this range are dangerous for human hearing. To avoid hearing damage in this area, employees must use hearing protector.

  10. Behind Start of Take-Off Roll Aircraft Sound Level Directivity Study - Revision 1

    Science.gov (United States)

    Lau, Michael C.; Roof, Christopher J.; Fleming, Gregg G.; Rapoza, Amanda S.; Boeker, Eric R.; McCurdy, David A.; Shepherd, Kevin P.

    2015-01-01

    The National Aeronautics and Space Administration (NASA), Langley Research Center (LaRC) and the Environmental Measurement and Modeling Division of the Department of Transportation's Volpe National Transportation Systems Center (Volpe) conducted a noise measurement study to examine aircraft sound level directivity patterns behind the start-of-takeoff roll. The study was conducted at Washington Dulles International Airport (IAD) from October 4 through 20, 2004.

  11. A further test of relevance of ASEL and CSEL in the determination of the rating sound level for shooting sounds

    NARCIS (Netherlands)

    Vos, J.

    1998-01-01

    In a previous study on the annoyance caused by shooting sounds [Proceedings Internoise '96, Vol. 5, 2231-2236], it was shown that an almost perfect prediction of the annoyance, as rated indoors with the windows closed, was obtained on the basis of the weighted sum of the outdoor A-weighted and

  12. Background radiation levels and medical exposure levels in Australia

    International Nuclear Information System (INIS)

    Webb, D.V.; Solomon, S.B.; Thomson, J.E.M.

    1999-01-01

    The average effective background dose received by the Australian population has been reassessed to be ∼1.5 millisievert (mSv) per year. Over half of this exposure arises from exposure from terrestrial radiation and cosmic rays, the remainder from radionuclides within the body and from inhalation of radon progeny. This background is to be compared with medical radiation, primarily diagnostic, which could add half as much again to the population exposure. This paper reviews research programmes carried out by the Australian Radiation Laboratory to study radiation exposure from natural background and from medical use. While the latter exposure is accepted to have a social benefit, there is a need to ensure that doses are no more than necessary to provide effective diagnosis and optimal treatment. Copyright (1999) Australasian Radiation Protection Society Inc

  13. The effect of interaural-level-difference fluctuations on the externalization of sound

    DEFF Research Database (Denmark)

    Catic, Jasmina; Santurette, Sébastien; Buchholz, Jörg M.

    2013-01-01

    Real-world sound sources are usually perceived as externalized and thus properly localized in both direction and distance. This is largely due to (1) the acoustic filtering by the head, torso, and pinna, resulting in modifications of the signal spectrum and thereby a frequency-dependent shaping...... of interaural cues and (2) interaural cues provided by the reverberation inside an enclosed space. This study first investigated the effect of room reverberation on the spectro-temporal behavior of interaural level differences (ILDs) by analyzing dummy-head recordings of speech played at different distances...... in a standard listening room. Next, the effect of ILD fluctuations on the degree of externalization was investigated in a psychoacoustic experiment performed in the same listening room. Individual binaural impulse responses were used to simulate a distant sound source delivered via headphones. The ILDs were...

  14. Summer sound-level characterization of the Deaf Smith County and Swisher County locations in the Palo Duro Basin, Texas

    International Nuclear Information System (INIS)

    1984-03-01

    A description of sound levels and sound sources in the Deaf Smith County and Swisher County locations in the Palo Duro Basin during a period representative of the summer season is presented. Included are data collected during the period August 4 through 8, 1982, for both locations. 3 references, 2 figures, 3 tables

  15. Winter sound-level characterization of the Deaf Smith County location in the Palo Duro Basin, Texas

    International Nuclear Information System (INIS)

    1984-03-01

    A description of sound levels and sound sources in the Deaf Smith County location in the Palo Duro Basin during a period representative of the winter season is presented. Data were collected during the period February 26 through March 1, 1983. 4 references, 1 figure, 3 tables

  16. The Effect of Exposure to High Noise Levels on the Performance and Rate of Error in Manual Activities.

    Science.gov (United States)

    Khajenasiri, Farahnaz; Zamanian, Alireza; Zamanian, Zahra

    2016-03-01

    Sound is among the significant environmental factors for people's health, and it has an important role in both physical and psychological injuries, and it also affects individuals' performance and productivity. The aim of this study was to determine the effect of exposure to high noise levels on the performance and rate of error in manual activities. This was an interventional study conducted on 50 students at Shiraz University of Medical Sciences (25 males and 25 females) in which each person was considered as its own control to assess the effect of noise on her or his performance at the sound levels of 70, 90, and 110 dB by using two factors of physical features and the creation of different conditions of sound source as well as applying the Two-Arm coordination Test. The data were analyzed using SPSS version 16. Repeated measurements were used to compare the length of performance as well as the errors measured in the test. Based on the results, we found a direct and significant association between the levels of sound and the length of performance. Moreover, the participant's performance was significantly different for different sound levels (at 110 dB as opposed to 70 and 90 dB, p < 0.05 and p < 0.001, respectively). This study found that a sound level of 110 dB had an important effect on the individuals' performances, i.e., the performances were decreased.

  17. Chronic exposure to low frequency noise at moderate levels causes impaired balance in mice.

    Directory of Open Access Journals (Sweden)

    Haruka Tamura

    Full Text Available We are routinely exposed to low frequency noise (LFN; below 0.5 kHz at moderate levels of 60-70 dB sound pressure level (SPL generated from various sources in occupational and daily environments. LFN has been reported to affect balance in humans. However, there is limited information about the influence of chronic exposure to LFN at moderate levels for balance. In this study, we investigated whether chronic exposure to LFN at a moderate level of 70 dB SPL affects the vestibule, which is one of the organs responsible for balance in mice. Wild-type ICR mice were exposed for 1 month to LFN (0.1 kHz and high frequency noise (HFN; 16 kHz at 70 dB SPL at a distance of approximately 10-20 cm. Behavior analyses including rotarod, beam-crossing and footprint analyses showed impairments of balance in LFN-exposed mice but not in non-exposed mice or HFN-exposed mice. Immunohistochemical analysis showed a decreased number of vestibular hair cells and increased levels of oxidative stress in LFN-exposed mice compared to those in non-exposed mice. Our results suggest that chronic exposure to LFN at moderate levels causes impaired balance involving morphological impairments of the vestibule with enhanced levels of oxidative stress. Thus, the results of this study indicate the importance of considering the risk of chronic exposure to LFN at a moderate level for imbalance.

  18. Profiles of noise exposure levels in South African mining

    CSIR Research Space (South Africa)

    Edwards, A

    2011-05-01

    Full Text Available were exposed to noise levels of above the 85 dBA legislated occupational exposure level. The conclusion was made that information obtained through the study could be developed into a national personal noise exposure database, including audiometric...

  19. PAH exposure levels in mudpuppy (amphibian)

    Energy Technology Data Exchange (ETDEWEB)

    Trudeau, F; Maisonneuve, F [Environment Canada, Canadian Wildlife Service, Hull, PQ (Canada); Gendron, A D [Quebec Univ., Montreal, PQ (Canada); Bishop, C A [Environment Canada, Canada Centre for Inland Waters, Burlington, ON (Canada)

    1999-12-31

    The presence of PAHs in the environment is of great concern because of the mutagenic, teratogenic and carcinogenic properties of the metabolites produced in exposed organisms. In recent years, exposure of fish to PAHs was demonstrated by the detection of pyrene-type metabolites in bile, using synchronous fluorescence spectrometry (SFS), which offers a rapid screening tool to estimate recent exposure to PAHs. In this experiment, the SFS technique was applied to mudpuppy (Necturus maculosus), a benthic carnivorous salamander found in the lakes and rivers of northeastern America, susceptible to the chronic effects of contaminants accumulated through its diet and through its contact with the contaminated sediment. Samples were taken from a variety of locations (Akwesasne River, Batiscan River, in the St.-Lawrence River System, Des Prairies River and Quesnel Bay in the Ottawa River System, Wolfe Island, Long Point and the Detroit River in the Great Lakes Basin). Results of the examination showed that mud puppies collected from the Detroit River had, by far, the highest concentrations of biliary 1-hydroxy pyrene (798 ng/ml), compared to 84 ng/ml, or less, in other animals in the sample.

  20. Radiation exposure levels in phosphate mining activities

    International Nuclear Information System (INIS)

    Othman, I.; Al-Hushari, M.; Raja, G.

    1992-01-01

    Radon, radon daughter concentration and gamma ray exposure rate were measured at different places in the phosphate mining areas of Syria. The grab sampling method was used. For radon measurements, discrete air samples without progeny were collected over short periods of time, whereas daughters were collected on filter paper. A three-count procedure was used for the measurement of radon daughter concentrations to improve accuracy. The measurements were carried out at 37 locations selected in the mines, factories, offices and homes in the mining area. The sampling was repeated monthly for a full calendar year. Workers and their families were classified in different categories according to the nature of their jobs. The doses were estimated using proper occupancy factors. The dose equivalent from radon daughters varies from 1 mSv.y -1 to a maximum of 10 mSv.y -1 . Radon concentrations vary from 100 Bq.m -3 to several hundreds. (author)

  1. Differential effects of suppressors on hazardous sound pressure levels generated by AR-15 rifles: Considerations for recreational shooters, law enforcement, and the military.

    Science.gov (United States)

    Lobarinas, Edward; Scott, Ryan; Spankovich, Christopher; Le Prell, Colleen G

    2016-01-01

    Firearm discharges produce hazardous levels of impulse noise that can lead to permanent hearing loss. In the present study, we evaluated the effects of suppression, ammunition, and barrel length on AR-15 rifles. Sound levels were measured left/right of a user's head, and 1-m left of the muzzle, per MIL-STD-1474-D, under both unsuppressed and suppressed conditions. Nine commercially available AR-15 rifles and 14 suppressors were used. Suppressors significantly decreased peak dB SPL at the 1-m location and the left ear location. However, under most rifle/ammunition conditions, levels remained above 140 dB peak SPL near a user's right ear. In a subset of conditions, subsonic ammunition produced values near or below 140 dB peak SPL. Overall suppression ranged from 7-32 dB across conditions. These data indicate that (1) suppressors reduce discharge levels to 140 dB peak SPL or below in only a subset of AR-15 conditions, (2) shorter barrel length and use of muzzle brake devices can substantially increase exposure level for the user, and (3) there are significant left/right ear sound pressure differences under suppressed conditions as a function of the AR-15 direct impingement design that must be considered during sound measurements to fully evaluate overall efficacy.

  2. Topography of sound level representation in the FM sweep selective region of the pallid bat auditory cortex.

    Science.gov (United States)

    Measor, Kevin; Yarrow, Stuart; Razak, Khaleel A

    2018-05-26

    Sound level processing is a fundamental function of the auditory system. To determine how the cortex represents sound level, it is important to quantify how changes in level alter the spatiotemporal structure of cortical ensemble activity. This is particularly true for echolocating bats that have control over, and often rapidly adjust, call level to actively change echo level. To understand how cortical activity may change with sound level, here we mapped response rate and latency changes with sound level in the auditory cortex of the pallid bat. The pallid bat uses a 60-30 kHz downward frequency modulated (FM) sweep for echolocation. Neurons tuned to frequencies between 30 and 70 kHz in the auditory cortex are selective for the properties of FM sweeps used in echolocation forming the FM sweep selective region (FMSR). The FMSR is strongly selective for sound level between 30 and 50 dB SPL. Here we mapped the topography of level selectivity in the FMSR using downward FM sweeps and show that neurons with more monotonic rate level functions are located in caudomedial regions of the FMSR overlapping with high frequency (50-60 kHz) neurons. Non-monotonic neurons dominate the FMSR, and are distributed across the entire region, but there is no evidence for amplitopy. We also examined how first spike latency of FMSR neurons change with sound level. The majority of FMSR neurons exhibit paradoxical latency shift wherein the latency increases with sound level. Moreover, neurons with paradoxical latency shifts are more strongly level selective and are tuned to lower sound level than neurons in which latencies decrease with level. These data indicate a clustered arrangement of neurons according to monotonicity, with no strong evidence for finer scale topography, in the FMSR. The latency analysis suggests mechanisms for strong level selectivity that is based on relative timing of excitatory and inhibitory inputs. Taken together, these data suggest how the spatiotemporal

  3. PERANCANGAN DAN IMPLEMENTASI SOUND LEVEL METER (SLM DALAM SKALA LABORATORIUM SEBAGAI ALAT UKUR INTENSITAS BUNYI

    Directory of Open Access Journals (Sweden)

    Jamaludin Jamaludin

    2016-11-01

    Keywords  : Sound Level Meter, Wave Mechanics Penelitian yang berbasis laboratorium merupakan implementasi dari Gelombang Mekanik (GM. Pada peristtiwa fisis ini akan diteliti tentang Gelombang Mekanik dalam mengukur Intensitas Bunyi. Guna untuk mengetahui SLM yang relevan menggunakan mic condenser serta menentukan kebisingan bunyi dalam tingkat frekuensi yang berbeda dalam skala Laboratorium. Pengujian intensitas bunyi dilakukan dalam kondisi ruang yang kedap suara serta perbandingan intensitas bunyi dengan SLM rancangan industri. Dalam penelitian ini juga membandingkan antara SLM Rancangan dengan SLM Nor-118. Sehingga data yang diperoleh adalah hasil dari pengambilan data yang kami lakukan antara SLM Rancangan dengan SLM Nor-118 bisa dikatakan relevan namun ada perbedaan selisih sebesar ±5.0 %. Dan pada saat frekuensi tertentu dia akan menurun yang disebabkan oleh beberapa faktor internal dan eksternal. Kesimpulan yang diambil adalah dalam setiap pengambilan data harus dalam kondisi ruang yang kedap suara sehingga ketika dalam pengambilan data tidak ada faktor yang mempengaruhi baik eksternal maupun internal. Kata Kunci : Sound Level Meter, Gelombang Mekanik

  4. Effects of high vs low-level radiation exposure

    International Nuclear Information System (INIS)

    Bond, V.P.

    1983-01-01

    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

  5. Sources and levels of ambient ocean sound near the Antarctic Peninsula.

    Directory of Open Access Journals (Sweden)

    Robert P Dziak

    Full Text Available Arrays of hydrophones were deployed within the Bransfield Strait and Scotia Sea (Antarctic Peninsula region from 2005 to 2009 to record ambient ocean sound at frequencies of up to 125 and 500 Hz. Icequakes, which are broadband, short duration signals derived from fracturing of large free-floating icebergs, are a prominent feature of the ocean soundscape. Icequake activity peaks during austral summer and is minimum during winter, likely following freeze-thaw cycles. Iceberg grounding and rapid disintegration also releases significant acoustic energy, equivalent to large-scale geophysical events. Overall ambient sound levels can be as much as ~10-20 dB higher in the open, deep ocean of the Scotia Sea compared to the relatively shallow Bransfield Strait. Noise levels become lowest during the austral winter, as sea-ice cover suppresses wind and wave noise. Ambient noise levels are highest during austral spring and summer, as surface noise, ice cracking and biological activity intensifies. Vocalizations of blue (Balaenoptera musculus and fin (B. physalus whales also dominate the long-term spectra records in the 15-28 and 89 Hz bands. Blue whale call energy is a maximum during austral summer-fall in the Drake Passage and Bransfield Strait when ambient noise levels are a maximum and sea-ice cover is a minimum. Fin whale vocalizations were also most common during austral summer-early fall months in both the Bransfield Strait and Scotia Sea. The hydrophone data overall do not show sustained anthropogenic sources (ships and airguns, likely due to low coastal traffic and the typically rough weather and sea conditions of the Southern Ocean.

  6. Metal Sounds Stiffer than Drums for Ears, but Not Always for Hands: Low-Level Auditory Features Affect Multisensory Stiffness Perception More than High-Level Categorical Information

    Science.gov (United States)

    Liu, Juan; Ando, Hiroshi

    2016-01-01

    Most real-world events stimulate multiple sensory modalities simultaneously. Usually, the stiffness of an object is perceived haptically. However, auditory signals also contain stiffness-related information, and people can form impressions of stiffness from the different impact sounds of metal, wood, or glass. To understand whether there is any interaction between auditory and haptic stiffness perception, and if so, whether the inferred material category is the most relevant auditory information, we conducted experiments using a force-feedback device and the modal synthesis method to present haptic stimuli and impact sound in accordance with participants’ actions, and to modulate low-level acoustic parameters, i.e., frequency and damping, without changing the inferred material categories of sound sources. We found that metal sounds consistently induced an impression of stiffer surfaces than did drum sounds in the audio-only condition, but participants haptically perceived surfaces with modulated metal sounds as significantly softer than the same surfaces with modulated drum sounds, which directly opposes the impression induced by these sounds alone. This result indicates that, although the inferred material category is strongly associated with audio-only stiffness perception, low-level acoustic parameters, especially damping, are more tightly integrated with haptic signals than the material category is. Frequency played an important role in both audio-only and audio-haptic conditions. Our study provides evidence that auditory information influences stiffness perception differently in unisensory and multisensory tasks. Furthermore, the data demonstrated that sounds with higher frequency and/or shorter decay time tended to be judged as stiffer, and contact sounds of stiff objects had no effect on the haptic perception of soft surfaces. We argue that the intrinsic physical relationship between object stiffness and acoustic parameters may be applied as prior

  7. Sound pressure levels generated at risk volume steps of portable listening devices: types of smartphone and genres of music.

    Science.gov (United States)

    Kim, Gibbeum; Han, Woojae

    2018-05-01

    The present study estimated the sound pressure levels of various music genres at the volume steps that contemporary smartphones deliver, because these levels put the listener at potential risk for hearing loss. Using six different smartphones (Galaxy S6, Galaxy Note 3, iPhone 5S, iPhone 6, LG G2, and LG G3), the sound pressure levels for three genres of K-pop music (dance-pop, hip-hop, and pop-ballad) and a Billboard pop chart of assorted genres were measured through an earbud for the first risk volume that was at the risk sign proposed by the smartphones, as well as consecutive higher volumes using a sound level meter and artificial mastoid. The first risk volume step of the Galaxy S6 and the LG G2, among the six smartphones, had the significantly lowest (84.1 dBA) and highest output levels (92.4 dBA), respectively. As the volume step increased, so did the sound pressure levels. The iPhone 6 was loudest (113.1 dBA) at the maximum volume step. Of the music genres, dance-pop showed the highest output level (91.1 dBA) for all smartphones. Within the frequency range of 20~ 20,000 Hz, the sound pressure level peaked at 2000 Hz for all the smartphones. The results showed that the sound pressure levels of either the first volume step or the maximum volume step were not the same for the different smartphone models and genres of music, which means that the risk volume sign and its output levels should be unified across the devices for their users. In addition, the risk volume steps proposed by the latest smartphone models are high enough to cause noise-induced hearing loss if their users habitually listen to music at those levels.

  8. EFFECT OF NATURE SOUND THERAPY ON THE LEVEL OF CORTISOL IN POSTPARTUM PRIMIPARA

    Directory of Open Access Journals (Sweden)

    Yulinda Laska

    2018-02-01

    Full Text Available Background: Prevalence of postpartum blues for Asia between 26-85%, while the prevalence in Indonesia is 50-70%. Of all women postpartum can experience this is experiencing stress, almost 80% of primiparous moms experience feelings of sadness after childbirth. These stresses can trigger an increase in cortisol. Music raises changes in brain wave status and stress hormones. Nature Sound music is music that has a slow tempo and can cause feelings relaxed and comfortable. Objective: To examine the effect of the nature music therapy on on cortisol levels in postpartum primipara. Methods: This was a true experimental study with pretest-posttest control group design. The study was conducted in the postpartum ward in the General Hospital of Semarang from November 2016 to January 2017. There were 39 postpartum primipara recruited in this study using simple random sampling divided into three groups: 1 the experiment group who received the nature music therapy for 15 minutes, 2 the experiment group who received the nature music therapy for 30 minutes, and 3 the control group. One-way ANOVA test was performed for data analysis. Results: One-way anova test showed p-value 0.010 (<0.05, which indicated that there was a statistically significant effect of the nature sound therapy on the cortisol level in the postpartum primipara. Conclusion: There was a significant effect of the nature music therapy on the cortisol levels in postpartum primipara. Thus, the application of nature music therapy can be an alternative therapy especially for postpartum primipara who experience emotional stress, physical, anxiety, and fatigue.

  9. Do high sound pressure levels of crowing in roosters necessitate passive mechanisms for protection against self-vocalization?

    Science.gov (United States)

    Claes, Raf; Muyshondt, Pieter G G; Dirckx, Joris J J; Aerts, Peter

    2018-02-01

    High sound pressure levels (>120dB) cause damage or death of the hair cells of the inner ear, hence causing hearing loss. Vocalization differences are present between hens and roosters. Crowing in roosters is reported to produce sound pressure levels of 100dB measured at a distance of 1m. In this study we measured the sound pressure levels that exist at the entrance of the outer ear canal. We hypothesize that roosters may benefit from a passive protective mechanism while hens do not require such a mechanism. Audio recordings at the level of the entrance of the outer ear canal of crowing roosters, made in this study, indeed show that a protective mechanism is needed as sound pressure levels can reach amplitudes of 142.3dB. Audio recordings made at varying distances from the crowing rooster show that at a distance of 0.5m sound pressure levels already drop to 102dB. Micro-CT scans of a rooster and chicken head show that in roosters the auditory canal closes when the beak is opened. In hens the diameter of the auditory canal only narrows but does not close completely. A morphological difference between the sexes in shape of a bursa-like slit which occurs in the outer ear canal causes the outer ear canal to close in roosters but not in hens. Copyright © 2017 Elsevier GmbH. All rights reserved.

  10. Televised antismoking advertising: effects of level and duration of exposure.

    Science.gov (United States)

    Dunlop, Sally; Cotter, Trish; Perez, Donna; Wakefield, Melanie

    2013-08-01

    We assessed the effects of levels and duration of exposure to televised antismoking advertising on cognitive and behavioral changes. We used data from a serial cross-sectional telephone survey with weekly interviews of adult smokers and recent quitters in New South Wales, Australia (n = 13,301), between April 2005 and December 2010. We merged survey data with commercial TV ratings data to estimate individuals' exposure to antismoking advertising. Logistic regression analyses indicated that after adjustment for a wide range of potential confounders, exposure to antismoking advertising at levels between 100 and 200 gross rating points per week on average over 6 to 9 weeks was associated with an increased likelihood of having (1) salient quitting thoughts and (2) recent quit attempts. Associations between exposure for shorter periods and these outcomes were not significant. Broadcasting schedules may affect the success of antismoking ads. Campaign planners should ensure advertising exposure at adequate frequency over relatively sustained periods to maximize impact.

  11. Acoustic characterization of a nonlinear vibroacoustic absorber at low frequencies and high sound levels

    Science.gov (United States)

    Chauvin, A.; Monteil, M.; Bellizzi, S.; Côte, R.; Herzog, Ph.; Pachebat, M.

    2018-03-01

    A nonlinear vibroacoustic absorber (Nonlinear Energy Sink: NES), involving a clamped thin membrane made in Latex, is assessed in the acoustic domain. This NES is here considered as an one-port acoustic system, analyzed at low frequencies and for increasing excitation levels. This dynamic and frequency range requires a suitable experimental technique, which is presented first. It involves a specific impedance tube able to deal with samples of sufficient size, and reaching high sound levels with a guaranteed linear response thank's to a specific acoustic source. The identification method presented here requires a single pressure measurement, and is calibrated from a set of known acoustic loads. The NES reflection coefficient is then estimated at increasing source levels, showing its strong level dependency. This is presented as a mean to understand energy dissipation. The results of the experimental tests are first compared to a nonlinear viscoelastic model of the membrane absorber. In a second step, a family of one degree of freedom models, treated as equivalent Helmholtz resonators is identified from the measurements, allowing a parametric description of the NES behavior over a wide range of levels.

  12. Hearing Threshold and Equal Loudness Level Contours of 1/3-octave Noise Bands in a Diffuse Sound Field

    DEFF Research Database (Denmark)

    Nielsen, Maja Kirstine E.; Poulsen, Torben

    1994-01-01

    Hearing threshold levels and equal loudness level contours of 1/3-octave noise bands at 40 phons and 60 phon were measured for 27 normal hearing listeners in an approximately diffuse sound field. The threshold data in the frequency range 125 Hz to 1 kHz were 3-6 dB higher than the values given...

  13. Exposure level of ergonomic risk factors in hotel industries

    Science.gov (United States)

    Nasrull Abdol Rahman, Mohd; Syahir Muhamad Jaffar, Mohd; Fahrul Hassan, Mohd; Zamani Ngali, Mohd; Pauline, Ong

    2017-08-01

    Ergonomic Risk Factors (ERFs) which contribute to Musculoskeletal Disorders (MSDs) among room attendants were considered as a problem or trouble since these ERFs would affect their work performance for hotel industries. The purpose of this study was to examine the exposure level of ERFs among room attendants in hotel industries. 65 of respondents were obtained from selected hotels in Peninsular Malaysia. Data were collected by direct observation via Workplace Ergonomic Risk Assessment (WERA) and Quick Exposure Checklist (QEC). There were 36 males and 29 females room attendants involved throughout the research. Most of room attendants experienced high exposure level for back, leg, forceful and vibration based on the exposure level evaluation through WERA while QEC results showed that all room attendants were found to have moderate exposure level for risk factors including back for movement use, shoulders/arms, wrists/hands and neck. All the results obtained showed that the related ERFs for MSDs were associated and essential ergonomic interventions are needed in order to eliminate risk of exposures to MSDs among room attendants in hotel industries.

  14. Contralateral routing of signals disrupts monaural level and spectral cues to sound localisation on the horizontal plane.

    Science.gov (United States)

    Pedley, Adam J; Kitterick, Pádraig T

    2017-09-01

    Contra-lateral routing of signals (CROS) devices re-route sound between the deaf and hearing ears of unilaterally-deaf individuals. This rerouting would be expected to disrupt access to monaural level cues that can support monaural localisation in the horizontal plane. However, such a detrimental effect has not been confirmed by clinical studies of CROS use. The present study aimed to exercise strict experimental control over the availability of monaural cues to localisation in the horizontal plane and the fitting of the CROS device to assess whether signal routing can impair the ability to locate sources of sound and, if so, whether CROS selectively disrupts monaural level or spectral cues to horizontal location, or both. Unilateral deafness and CROS device use were simulated in twelve normal hearing participants. Monaural recordings of broadband white noise presented from three spatial locations (-60°, 0°, and +60°) were made in the ear canal of a model listener using a probe microphone with and without a CROS device. The recordings were presented to participants via an insert earphone placed in their right ear. The recordings were processed to disrupt either monaural level or spectral cues to horizontal sound location by roving presentation level or the energy across adjacent frequency bands, respectively. Localisation ability was assessed using a three-alternative forced-choice spatial discrimination task. Participants localised above chance levels in all conditions. Spatial discrimination accuracy was poorer when participants only had access to monaural spectral cues compared to when monaural level cues were available. CROS use impaired localisation significantly regardless of whether level or spectral cues were available. For both cues, signal re-routing had a detrimental effect on the ability to localise sounds originating from the side of the deaf ear (-60°). CROS use also impaired the ability to use level cues to localise sounds originating from

  15. Pressure sound level measurements at an educational environment in Goiânia, Goiás, Brazil

    Science.gov (United States)

    Costa, J. J. L.; do Nascimento, E. O.; de Oliveira, L. N.; Caldas, L. V. E.

    2018-03-01

    In this work, 25 points located on the ground floor of the Federal Institute of Education, Science and Technology of Goias - IFG - Campus Goiânia, were analyzed in morning periods of two Saturdays. The pressure sound levels were measured at internal and external environments during routine activities seeking to perform an environmental monitoring at this institution. The initial hypothesis was that an amusement park (Mutirama Park) was responsible for originating noise pollution in the institute, but the results showed, within the campus environment, sound pressure levels in accordance with the Municipal legislation of Goiânia for all points.

  16. Sound levels, hearing habits and hazards of using portable cassete players

    Science.gov (United States)

    Hellström, P.-A.; Axelsson, A.

    1988-12-01

    The maximum output sound pressure level ( SPL) from different types of portable cassette players (PCP's) and different headphones was analyzed by using KEMAR in one-third octave bands. The equivalent free-field dB(A) level (EqA-FFSL) was computed from the one-third octave bands corrected by the free-field to the eardrum transfer function. The dB(A) level varied between 104 dB from a low-cost PCP with supra-aural headphones (earphones with headbands and foam pads fitting against the pinna) to 126 dB from a high quality PCP with semi-aural headphones (small earphones without headbands to be used in the concha of the external ear). The cassette tapes used in this study were recorded with music, white noise, narrowband noise and pure tones. The equivalent and maximum SPL was measured in the ear canal (1 mm from eardrum) with the use of mini-microphones in 15 young subjects listening to pop music from PCP's at the highest level they considered comfortable. These SPL measurements corresponded to 112 dB(A) in free field. In a temporary threshold shift ( TTS) study, ten teenagers—four girls and six boys—listened to pop music for 1 h with PCP's at a level they enjoyed. The mean TTS value was 5-10 dB for frequencies between 1 and 8 kHz. In one subject the maximum TTS was 35 dB at 5-6 dB kHz. In order to acquire information about listening habits among youngsters using PCP's, 154 seventh and eighth graders (age 14-15) were interviewed. They used PCP's much less than expected during most of the year, but an increase was reported during the summer holidays.

  17. Radiation exposure by monitors and effects of whistling sound on hearing at workplaces in TV and film production sectors

    International Nuclear Information System (INIS)

    Strasser, H.

    1988-01-01

    Information transmission by means of VDUs, spreading at present rapidly in office work and some branches of the industrial production, is not only an auxiliary means but the essential destination and objective of working activities in specific areas of the media sector. By the progression of the video technique a further concentration of VDT work and the increasing gravity of all advantages and disadvantages is to be expected in the film and TV sectors. The real radiation exposure of the technical staff involved in working with and at monitors and potential risks of hearing by whistling sounds sent out by these apparatuses are analysed and evaluated. Experiences in health hazards by radiation from VDUs in office work had to be adapted adequately to the specific working conditions at work places in film and TV productions. (orig./HP) [de

  18. Development of acute exposure guideline levels for airborne exposures to hazardous substances.

    Science.gov (United States)

    Krewski, Daniel; Bakshi, Kulbir; Garrett, Roger; Falke, Ernest; Rusch, George; Gaylor, David

    2004-04-01

    Hazardous substances can be released into the atmosphere due to industrial and transportation accidents, fires, tornadoes, earthquakes, and terrorists, thereby exposing workers and the nearby public to potential adverse health effects. Various enforceable guidelines have been set by regulatory agencies for worker and ambient air quality. However, these exposure levels generally are not applicable to rare lifetime acute exposures, which possibly could occur at high concentrations. Acute exposure guideline levels (AEGLs) provide estimates of concentrations for airborne exposures for an array of short durations that possibly could cause mild (AEGL-1), severe, irreversible, potentially disabling adverse health effects (AEGL-2), or life threatening effects (AEGL-3). These levels can be useful for emergency responders and planners in reducing or eliminating potential risks to the public. Procedures and methodologies for deriving AEGLs are reviewed in this paper that have been developed in the United States, with direct input from international representatives of OECD member-countries, by the National Advisory Committee for Acute Exposure Guidelines for Hazardous Substances and reviewed by the National Research Council. Techniques are discussed for the extrapolation of effects across different exposure durations. AEGLs provide a viable approach for assisting in the prevention, planning, and response to acute airborne exposures to toxic agents.

  19. Assessment of narghile (shisha, hookah smokers’ actual exposure to toxic chemicals requires further sound studies

    Directory of Open Access Journals (Sweden)

    2011-05-01

    Full Text Available Tobacco smoking is hazardous for health. However, not all forms of tobacco use entail the same risks and the latter should be studied and compared in a sound realistic way. Smoking machines for cigarettes (which are consumed in a few minutes were early designed as a tool to evaluate the actual intake of toxic substances (‘toxicants’ by smokers. However, the yields (tar, nicotine, CO, etc. provided by such machines poorly reflect the actual human smoking behaviour known to depend on numerous factors (anxiety, emotions, anthropological situation, etc.. In the case of narghile smoking, the problems are even more complex, particularly because of the much longer duration of a session. A recent study from the US-American University of Beirut was based on a field smoking topography and claimed consistency with a laboratory smoking machine. We offer a point by point critical analysis of such methods on which most of the ‘waterpipe’ antismoking literature since 2002 is based.

  20. The Influence of Fundamental Frequency and Sound Pressure Level Range on Breathing Patterns in Female Classical Singing

    Science.gov (United States)

    Collyer, Sally; Thorpe, C. William; Callaghan, Jean; Davis, Pamela J.

    2008-01-01

    Purpose: This study investigated the influence of fundamental frequency (F0) and sound pressure level (SPL) range on respiratory behavior in classical singing. Method: Five trained female singers performed an 8-s messa di voce (a crescendo and decrescendo on one F0) across their musical F0 range. Lung volume (LV) change was estimated, and…

  1. Exterior sound level measurements of over-snow vehicles at Yellowstone National Park.

    Science.gov (United States)

    2008-09-30

    Sounds associated with oversnow vehicles, such as snowmobiles and snowcoaches, are an : important management concern at Yellowstone and Grand Teton National Parks. The John A. : Volpe National Transportation Systems Centers Environmental Measureme...

  2. Effect of Low Level Cadmium Exposure on Superoxide Dismutase ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of low level cadmium (Cd) exposure on the activity of superoxide dismutase ... cancer, aging and a diversity of diseases [5]. Superoxide .... responsible for the long biological half-life of cadmium [12]. ... indicator of the balance between the damaging effects and the ... Scand J Work Environ.

  3. Televised Antismoking Advertising: Effects of Level and Duration of Exposure

    Science.gov (United States)

    Cotter, Trish; Perez, Donna; Wakefield, Melanie

    2013-01-01

    Objectives. We assessed the effects of levels and duration of exposure to televised antismoking advertising on cognitive and behavioral changes. Methods. We used data from a serial cross-sectional telephone survey with weekly interviews of adult smokers and recent quitters in New South Wales, Australia (n = 13 301), between April 2005 and December 2010. We merged survey data with commercial TV ratings data to estimate individuals’ exposure to antismoking advertising. Results. Logistic regression analyses indicated that after adjustment for a wide range of potential confounders, exposure to antismoking advertising at levels between 100 and 200 gross rating points per week on average over 6 to 9 weeks was associated with an increased likelihood of having (1) salient quitting thoughts and (2) recent quit attempts. Associations between exposure for shorter periods and these outcomes were not significant. Conclusions. Broadcasting schedules may affect the success of antismoking ads. Campaign planners should ensure advertising exposure at adequate frequency over relatively sustained periods to maximize impact. PMID:23763419

  4. Continuous Re-Exposure to Environmental Sound Cues During Sleep Does Not Improve Memory for Semantically Unrelated Word Pairs.

    Science.gov (United States)

    Donohue, Kelly C; Spencer, Rebecca M C

    2011-06-01

    Two recent studies illustrated that cues present during encoding can enhance recall if re-presented during sleep. This suggests an academic strategy. Such effects have only been demonstrated with spatial learning and cue presentation was isolated to slow wave sleep (SWS). The goal of this study was to examine whether sounds enhance sleep-dependent consolidation of a semantic task if the sounds are re-presented continuously during sleep. Participants encoded a list of word pairs in the evening and recall was probed following an interval with overnight sleep. Participants encoded the pairs with the sound of "the ocean" from a sound machine. The first group slept with this sound; the second group slept with a different sound ("rain"); and the third group slept with no sound. Sleeping with sound had no impact on subsequent recall. Although a null result, this work provides an important test of the implications of context effects on sleep-dependent memory consolidation.

  5. Aggregate-level lead exposure, gun violence, homicide, and rape.

    Science.gov (United States)

    Boutwell, Brian B; Nelson, Erik J; Qian, Zhengmin; Vaughn, Michael G; Wright, John P; Beaver, Kevin M; Barnes, J C; Petkovsek, Melissa; Lewis, Roger; Schootman, Mario; Rosenfeld, Richard

    2017-01-01

    An increasing body of research has linked the geographic distribution of lead with various indicators of criminal and antisocial behavior. The current study, using data from an ongoing project related to lead exposure in St. Louis City, MO, analyzed the association between aggregate blood lead levels and specific indicators violent crime within the city. Ecological study. St. Louis, Missouri. Blood lead levels. Official reports of violent crimes were categorized as 1) crimes involving a firearm (yes/no), 2) assault crimes (with or without a firearm), 3) robbery crimes (with or without a firearm), 4) homicides and 5) rape. With the exception of rape, aggregate blood-lead levels were statistically significant predictors of violent crime at the census tract level. The risk ratios for each of the outcome measures were as follows: firearm crimes 1.03 (1.03-1.04), assault crimes 1.03 (1.02-1.03), robbery crimes 1.03 (1.02-1.04), homicide 1.03 (1.01, 1.04), and rape 1.01 (0.99-1.03). Extending prior research in St. Louis, results suggest that aggregated lead exposure at the census tract level predicted crime outcomes, even after accounting for important sociological variables. Moving forward, a more developed understanding of aggregate level crime may necessitate a shift toward studying the synergy between sociological and biological risk factors such as lead exposure.

  6. Toxicity levels to humans during acute exposure to hydrogen fluoride

    International Nuclear Information System (INIS)

    Halton, D.M.; Dranitsaris, P.; Baynes, C.J.

    1984-11-01

    A literature review was conducted of the acute toxicity of hydrogen fluoride (HF) with emphasis on the effects of inhalation of gaseous HF. The data and findings of the relevant references were summarized under four categories: animal studies, controlled human studies, community exposure and industrial exposure. These were critically reviewed and then lethal concentration-time relationships were developed for humans, corresponding to LCsub(LO), LCsub(10) and LCsub(50) levels. The effects of age, health and other physiological variables on the sensitivity to HF were discussed, as well as antagonistic and synergistic effects with other substances

  7. Standing operating procedures for developing acute exposure guideline levels for hazardous chemicals

    National Research Council Canada - National Science Library

    National Research Council (U.S.). Subcommittee on Acute Exposure Guideline Levels

    2001-01-01

    Standing Operating Procedures for Developing Acute Exposure Guideline Levels for Hazardous Chemicals contains a detailed and comprehensive methodology for developing acute exposure guideline levels (AEGLs...

  8. Occupational exposure to diesel engine exhaust and serum cytokine levels.

    Science.gov (United States)

    Dai, Yufei; Ren, Dianzhi; Bassig, Bryan A; Vermeulen, Roel; Hu, Wei; Niu, Yong; Duan, Huawei; Ye, Meng; Meng, Tao; Xu, Jun; Bin, Ping; Shen, Meili; Yang, Jufang; Fu, Wei; Meliefste, Kees; Silverman, Debra; Rothman, Nathaniel; Lan, Qing; Zheng, Yuxin

    2018-03-01

    The International Agency for Research on Cancer has classified diesel engine exhaust (DEE) as a human lung carcinogen. Given that inflammation is suspected to be an important underlying mechanism of lung carcinogenesis, we evaluated the relationship between DEE exposure and the inflammatory response using data from a cross-sectional molecular epidemiology study of 41 diesel engine testing workers and 46 unexposed controls. Repeated personal exposure measurements of PM 2.5 and other DEE constituents were taken for the diesel engine testing workers before blood collection. Serum levels of six inflammatory biomarkers including interleukin (IL)-1, IL-6, IL-8, tumor necrosis factor (TNF)-α, macrophage inflammatory protein (MIP)-1β, and monocyte chemotactic protein (MCP)-1 were analyzed in all subjects. Compared to unexposed controls, concentrations of MIP-1β were significantly reduced by ∼37% in DEE exposed workers (P 397 µg/m 3 ) compared to unexposed controls. Further, significant inverse exposure-response relationships for IL-8 and MCP-1 were also found in relation to increasing PM 2.5 levels among the DEE exposed workers. Given that IL-8, MIP-1β, and MCP-1 are chemokines that play important roles in recruitment of immunocompetent cells for immune defense and tumor cell clearance, the observed lower levels of these markers with increasing PM 2.5 exposure may provide insight into the mechanism by which DEE promotes lung cancer. Environ. Mol. Mutagen. 59:144-150, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  9. Occupational exposure to beryllium in French enterprises: a survey of airborne exposure and surface levels.

    Science.gov (United States)

    Vincent, Raymond; Catani, Jacques; Créau, Yvon; Frocaut, Anne-Marie; Good, Andrée; Goutet, Pierre; Hou, Alain; Leray, Fabrice; André-Lesage, Marie-Ange; Soyez, Alain

    2009-06-01

    An assessment survey of occupational exposure to beryllium (Be) was conducted in France between late 2004 and the end of 2006. Exposure estimates were based on the analytical results of samples collected from workplace air and from work surfaces in 95 facilities belonging to 37 sectors of activity. The results of this study indicated airborne Be concentrations in excess of the occupational exposure limit value of 2 microg m(-3) recommended in France. Metallurgy and electronic component manufacturing represented the activities and occupations where workers had the highest arithmetic mean exposures to Be. Surface contamination levels were also high and frequently exceeded thresholds recommended by different bodies. These results should prompt the development of prevention programmes that include Be substitution, process control and surface decontamination, in conjunction with suitable medical surveillance.

  10. Chronic exposure to environmental levels of tribromophenol impairs zebrafish reproduction

    International Nuclear Information System (INIS)

    Deng Jun; Liu Chunsheng; Yu Liqin; Zhou Bingsheng

    2010-01-01

    Tribromophenol (2,4,6-TBP) is ubiquitously found in aquatic environments and biota. In this study, we exposed zebrafish embryos (F 0 ; 2'''' days post-fertilization, dpf) to environmental concentration (0.3 μg/L) and a higher concentration (3.0 μg/L) of TBP and assessed the impact of chronic exposure (120 dpf) on reproduction. TBP exposure did not cause a significant increase in the malformation and reduction in the survival in the F 0 -generation fish. After TBP exposure, the plasma testosterone and estradiol levels significantly increased in males and decreased in females. The transcription of steroidogenic genes (3β-HSD, 17β-HSD, CYP17, CYP19A, CYP19B) was significantly upregulated in the brain and testes in males and downregulated in the brain and ovary in females. TBP exposure significantly downregulated and upregulated the expression of VTG in the liver of female and male fish, respectively. Meanwhile, TBP exposure altered the sex ratio toward a male-dominant state. The F 1 -generation larvae exhibited increased malformation, reduced survival, and retarded growth, suggesting that TBP in the aquatic environment has significant adverse effects on fish population.

  11. Characteristics and prediction of sound level in extra-large spaces

    OpenAIRE

    Wang, C.; Ma, H.; Wu, Y.; Kang, J.

    2018-01-01

    This paper aims to examine sound fields in extra-large spaces, which are defined in this paper as spaces used by people, with a volume approximately larger than 125,000m 3 and absorption coefficient less than 0.7. In such spaces inhomogeneous reverberant energy caused by uneven early reflections with increasing volume has a significant effect on sound fields. Measurements were conducted in four spaces to examine the attenuation of the total and reverberant energy with increasing source-receiv...

  12. A Mixed-Methods Trial of Broad Band Noise and Nature Sounds for Tinnitus Therapy: Group and Individual Responses Modeled under the Adaptation Level Theory of Tinnitus.

    Science.gov (United States)

    Durai, Mithila; Searchfield, Grant D

    2017-01-01

    Objectives: A randomized cross-over trial in 18 participants tested the hypothesis that nature sounds, with unpredictable temporal characteristics and high valence would yield greater improvement in tinnitus than constant, emotionally neutral broadband noise. Study Design: The primary outcome measure was the Tinnitus Functional Index (TFI). Secondary measures were: loudness and annoyance ratings, loudness level matches, minimum masking levels, positive and negative emotionality, attention reaction and discrimination time, anxiety, depression and stress. Each sound was administered using MP3 players with earbuds for 8 continuous weeks, with a 3 week wash-out period before crossing over to the other treatment sound. Measurements were undertaken for each arm at sound fitting, 4 and 8 weeks after administration. Qualitative interviews were conducted at each of these appointments. Results: From a baseline TFI score of 41.3, sound therapy resulted in TFI scores at 8 weeks of 35.6; broadband noise resulted in significantly greater reduction (8.2 points) after 8 weeks of sound therapy use than nature sounds (3.2 points). The positive effect of sound on tinnitus was supported by secondary outcome measures of tinnitus, emotion, attention, and psychological state, but not interviews. Tinnitus loudness level match was higher for BBN at 8 weeks; while there was little change in loudness level matches for nature sounds. There was no change in minimum masking levels following sound therapy administration. Self-reported preference for one sound over another did not correlate with changes in tinnitus. Conclusions: Modeled under an adaptation level theory framework of tinnitus perception, the results indicate that the introduction of broadband noise shifts internal adaptation level weighting away from the tinnitus signal, reducing tinnitus magnitude. Nature sounds may modify the affective components of tinnitus via a secondary, residual pathway, but this appears to be less important

  13. Glutathione level after long-term occupational elemental mercury exposure

    International Nuclear Information System (INIS)

    Kobal, Alfred Bogomir; Prezelj, Marija; Horvat, Milena; Krsnik, Mladen; Gibicar, Darija; Osredkar, Josko

    2008-01-01

    Many in vitro and in vivo studies have elucidated the interaction of inorganic mercury (Hg) and glutathione. However, human studies are limited. In this study, we investigated the potential effects of remote long-term intermittent occupational elemental Hg vapour (Hg o ) exposure on erythrocyte glutathione levels and some antioxidative enzyme activities in ex-mercury miners in the period after exposure. The study included 49 ex-mercury miners divided into subgroups of 28 still active, Hg o -not-exposed miners and 21 elderly retired miners, and 41 controls, age-matched to the miners subgroup. The control workers were taken from 'mercury-free works'. Reduced glutathione (GSH) and oxidized disulphide glutathione (GSSG) concentrations in haemolysed erythrocytes were determined by capillary electrophoresis, while total glutathione (total GSH) and the GSH/GSSG ratio were calculated from the determined values. Catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) activities in erythrocytes were measured using commercially available reagent kits, while urine Hg (U-Hg) concentrations were determined by cold vapour atomic absorption (CVAAS). No correlation of present U-Hg levels, GSH, GSSG, and antioxidative enzymes with remote occupational biological exposure indices were found. The mean CAT activity in miners and retired miners was significantly higher (p o could be an inductive and additive response to maintain the balance between GSH and antioxidative enzymes in interaction with the Hg body burden accumulated during remote occupational exposure, which does not represent a severely increased oxidative stress

  14. Radiation-induced taste aversion: effects of radiation exposure level and the exposure-taste interval

    International Nuclear Information System (INIS)

    Spector, A.C.; Smith, J.C.; Hollander, G.R.

    1986-01-01

    Radiation-induced taste aversion has been suggested to possibly play a role in the dietary difficulties observed in some radiotherapy patients. In rats, these aversions can still be formed even when the radiation exposure precedes the taste experience by several hours. This study was conducted to examine whether increasing the radiation exposure level could extend the range of the exposure-taste interval that would still support the formation of a taste aversion. Separate groups of rats received either a 100 or 300 R gamma-ray exposure followed 1, 3, 6, or 24 h later by a 10-min saccharin (0.1% w/v) presentation. A control group received a sham exposure followed 1 h later by a 10-min saccharin presentation. Twenty-four hours following the saccharin presentation all rats received a series of twelve 23-h two-bottle preference tests between saccharin and water. The results indicated that the duration of the exposure-taste interval plays an increasingly more important role in determining the initial extent of the aversion as the dose decreases. The course of recovery from taste aversion seems more affected by dose than by the temporal parameters of the conditioning trial

  15. Sound Photographs to reveal vehicle pass-by sources with a calibrated source-strength level

    NARCIS (Netherlands)

    Mast, A.; Dool, T.C. van den; Toorn, J.D. van der; Watts, G.

    2003-01-01

    In national and European discussions, it appears that the conventional sound measurement techniques are insufficient to answer some relevant questions with respect to source strength of road vehicles. An example of such a question is: What is the importance of tyre-road noise on the one hand and

  16. Enhanced UV exposure on a ski-field compared with exposures at sea level.

    Science.gov (United States)

    Allen, Martin; McKenzie, Richard

    2005-05-01

    Personal erythemal UV monitoring badges, which were developed to monitor the UV exposure of school children, were used to measure UV exposures received by one of the authors (MA) at the Mt Hutt ski-field, in New Zealand. These were then compared with measurements taken at the same times from a nearby sea level site in Christchurch city. The badges were designed to give instantaneous readings of erythemally-weighted (i.e., "sun burning") UV radiation and were cross-calibrated against meteorological grade UV instruments maintained by the National Institute of Water & Atmospheric Research (NIWA). All skiing and calibration days were clear and almost exclusively cloud free. It was found that the UV maxima for horizontal surfaces at the ski-field (altitude approximately 2 km) were 20-30% greater than at the low altitude site. Larger differences between the sites were observed when the sensor was oriented perpendicular to the sun. The personal doses of UV received by a sensor on the skier's lapel during two days of skiing activity were less than those received by a stationary detector on a horizontal surface near sea level. The exposures depended strongly on the time of year, and in mid-October the maximum UV intensity on the ski-field was 60% greater than in mid-September. The UV exposure levels experienced during skiing were smaller than the summer maxima at low altitudes.

  17. Perinatal alcohol exposure enhances nocistatin levels in adulthood.

    Science.gov (United States)

    Tekes, Kornélia; Hantos, Mónika; Gyenge, Melinda; Csaba, Gyorgy

    2007-06-01

    In earlier experiments perinatal hormonal imprinting by alcohol decreased the hormone content of immune cells for life. In the present study, both a single day (15% on the third postnatal day) and a long-term treatment schedule of alcohol exposure (3% for 21 days) of dams during lactation significantly (P < 0.01) enhanced endogenous levels of nocistatin in the blood plasma as well as in the cerebrospinal fluid of the offspring, measured in 3-month-old rats. Our data suggest that alcohol consumption during lactation can cause a life-long influence on nocistatin levels in the offspring and most likely modify nocistatin-related functions such as pain tolerance.

  18. Occupational exposure to mercury. What is a safe level?

    OpenAIRE

    Moienafshari, R.; Bar-Oz, B.; Koren, G.

    1999-01-01

    QUESTION: One of my pregnant patients, a dental hygienist, uses mercury in her workplace, but appears to have no symptoms of mercury toxicity. She has heard that mercury might affect her fetus. What should I recommend to her? What is a safe level of mercury in the air for pregnant women? ANSWER: Testing for levels of mercury in whole blood and, preferably, urine is useful for confirming exposure. Currently, mercury vapour concentrations greater than 0.01 mg/m3 are considered unsafe. Also, wom...

  19. Low level exposure to chemicals and immune system

    International Nuclear Information System (INIS)

    Colosio, C.; Birindelli, S.; Corsini, E.; Galli, C.L.; Maroni, M.

    2005-01-01

    Industrialized countries are facing an increase of diseases attributable to an alteration of the immune system function, and concern is growing that this trend could be at least partially attributable to new and modified patterns of exposure to chemicals. Among chemicals matter of concern, pesticides can be included. The Authors have reviewed the existing evidence of pesticide immunotoxicity in humans, showing that existing data are inadequate to raise conclusions on the immunotoxic risk related to these compounds. The limits of existing studies are: poor knowledge on exposure levels, heterogeneity of the approach, and difficulty in giving a prognostic significance to the slight changes often observed. To overcome these limits, the Authors have proposed a tier approach, based on three steps: the first, addressed at pointing out a possible immunomodulation; the second, at refining the results and the third one, when needed, to finalize the study and to point out concordance with previous results. Studies should preferably be carried out through comparison of pre- and post-exposure findings in the same groups of subjects to be examined immediately after the end of the exposure. A simplification of the first step approach can be used by the occupational health physician and the occupational toxicologist. Conclusions on the prognostic significance of the slight changes often observed will be reached only by validating the hypothesis generated by field studies with an epidemiological approach. In this field, the most useful option is represented by longitudinal perspective studies

  20. Investigation of the Sound Pressure Level (SPL) of earphones during music listening with the use of physical ear canal models

    Science.gov (United States)

    Aying, K. P.; Otadoy, R. E.; Violanda, R.

    2015-06-01

    This study investigates on the sound pressure level (SPL) of insert-type earphones that are commonly used for music listening of the general populace. Measurements of SPL from earphones of different respondents were measured by plugging the earphone to a physical ear canal model. Durations of the earphone used for music listening were also gathered through short interviews. Results show that 21% of the respondents exceed the standard loudness/duration relation recommended by the World Health Organization (WHO).

  1. Neural Correlates of Exposure to Traumatic Pictures and Sound in Vietnam Combat Veterans with and without Posttraumatic Stress Disorder: A Positron Emission Tomography Study

    Science.gov (United States)

    Bremner, J. Douglas; Staib, Lawrence H.; Kaloupek, Danny; Southwick, Steven M.; Soufer, Robert; Charney, Dennis S.

    2011-01-01

    Background Patients with posttraumatic stress disorder (PTSD) show a reliable increase in PTSD symptoms and physiological reactivity following exposure to traumatic pictures and sounds. In this study neural correlates of exposure to traumatic pictures and sounds were measured in PTSD. Methods Positron emission tomography and H2[15O] were used to measure cerebral blood flow during exposure to combat-related and neutral pictures and sounds in Vietnam combat veterans with and without PTSD. Results Exposure to traumatic material in PTSD (but not non-PTSD) subjects resulted in a decrease in blood flow in medial prefrontal cortex (area 25), an area postulated to play a role in emotion through inhibition of amygdala responsiveness. Non-PTSD subjects activated anterior cingulate (area 24) to a greater degree than PTSD patients. There were also differences in cerebral blood flow response in areas involved in memory and visuospatial processing (and by extension response to threat), including posterior cingulate (area 23), precentral (motor) and inferior parietal cortex, and lingual gyrus. There was a pattern of increases in PTSD and decreases in non-PTSD subjects in these areas. Conclusions The findings suggest that functional alterations in specific cortical and subcortical brain areas involved in memory, visuospatial processing, and emotion underlie the symptoms of patients with PTSD. PMID:10202567

  2. Elevated blood lead levels from exposure via a radiator workshop.

    Science.gov (United States)

    Treble, R G; Thompson, T S; Morton, D N

    1998-04-01

    Elevated lead levels were discovered in blood samples collected from family members where both the father and the mother worked in a radiator repair workshop. The father and mother were found to have blood lead levels of 2.0 and 0.5 mumol/L (41.7 and 10.4 micrograms/dL), respectively. The father's blood lead level was just below the Canadian occupational health and safety intervention level (2.5 mumol/L or 52.1 micrograms/dL). The two children had blood lead levels of 1.0 and 0.8 mumol/L (20.8 and 16.7 micrograms/dL), both of which are in excess of the recommended guideline for intervention in the case of children (0.5 mumol/L or 10.4 micrograms/dL). The exposure of the two children was possibly due to a combination of pathways including exposure at the workshop itself during visits and also the transportation of lead-containing dust to the home environment.

  3. An Improved Prediction Model for the Impact Sound Level of Lightweight Floors: Introducing Decoupled Floor-Ceiling and Beam-Plate Moment

    DEFF Research Database (Denmark)

    Mosharrof, Mohammad Sazzad; Brunskog, Jonas; Ljunggren, Fredrik

    2011-01-01

    the impact sound pressure level in a receiving room for a coupled floor structure where floor and ceiling are rigidly connected by beams. A theoretical model for predicting the impact sound level for a decoupled floor structure, which has no rigid mechanical connections between the floor and the ceiling......, is developed. An analytical method has been implemented, where a spatial Fourier transform method as well as the Poisson’s sum formula is applied to model transformed plate displacements. Radiated sound power was calculated from these displacements and normalized sound pressure levels were calculated in one...... and is found to be dependent on frequency, showing significant improvement in predicting impact sound level at high frequency region....

  4. Sound localization and occupational noise

    Directory of Open Access Journals (Sweden)

    Pedro de Lemos Menezes

    2014-02-01

    Full Text Available OBJECTIVE: The aim of this study was to determine the effects of occupational noise on sound localization in different spatial planes and frequencies among normal hearing firefighters. METHOD: A total of 29 adults with pure-tone hearing thresholds below 25 dB took part in the study. The participants were divided into a group of 19 firefighters exposed to occupational noise and a control group of 10 adults who were not exposed to such noise. All subjects were assigned a sound localization task involving 117 stimuli from 13 sound sources that were spatially distributed in horizontal, vertical, midsagittal and transverse planes. The three stimuli, which were square waves with fundamental frequencies of 500, 2,000 and 4,000 Hz, were presented at a sound level of 70 dB and were randomly repeated three times from each sound source. The angle between the speaker's axis in the same plane was 45°, and the distance to the subject was 1 m. RESULT: The results demonstrate that the sound localization ability of the firefighters was significantly lower (p<0.01 than that of the control group. CONCLUSION: Exposure to occupational noise, even when not resulting in hearing loss, may lead to a diminished ability to locate a sound source.

  5. Prenatal androgen exposure and children's aggressive behavior and activity level.

    Science.gov (United States)

    Spencer, Debra; Pasterski, Vickie; Neufeld, Sharon; Glover, Vivette; O'Connor, Thomas G; Hindmarsh, Peter C; Hughes, Ieuan A; Acerini, Carlo L; Hines, Melissa

    2017-11-01

    Some human behaviors, including aggression and activity level, differ on average for males and females. Here we report findings from two studies investigating possible relations between prenatal androgen and children's aggression and activity level. For study 1, aggression and activity level scores for 43 girls and 38 boys, aged 4 to 11years, with congenital adrenal hyperplasia (CAH, a genetic condition causing increased adrenal androgen production beginning prenatally) were compared to those of similarly-aged, unaffected relatives (41 girls, 31 boys). Girls with CAH scored higher on aggression than unaffected girls, d=0.69, and unaffected boys scored higher on activity level than unaffected girls, d=0.50. No other group differences were significant. For study 2, the relationship of amniotic fluid testosterone to aggression and activity level was investigated in typically-developing children (48 girls, 44 boys), aged 3 to 5years. Boys scored higher than girls on aggression, d=0.41, and activity level, d=0.50. However, amniotic fluid testosterone was not a significant predictor of aggression or activity level for either sex. The results of the two studies provide some support for an influence of prenatal androgen exposure on children's aggressive behavior, but not activity level. The within-sex variation in amniotic fluid testosterone may not be sufficient to allow reliable assessment of relations to aggression or activity level. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Brief report: sound output of infant humidifiers.

    Science.gov (United States)

    Royer, Allison K; Wilson, Paul F; Royer, Mark C; Miyamoto, Richard T

    2015-06-01

    The sound pressure levels (SPLs) of common infant humidifiers were determined to identify the likely sound exposure to infants and young children. This primary investigative research study was completed at a tertiary-level academic medical center otolaryngology and audiology laboratory. Five commercially available humidifiers were obtained from brick-and-mortar infant supply stores. Sound levels were measured at 20-, 100-, and 150-cm distances at all available humidifier settings. Two of 5 (40%) humidifiers tested had SPL readings greater than the recommended hospital infant nursery levels (50 dB) at distances up to 100 cm. In this preliminary study, it was demonstrated that humidifiers marketed for infant nurseries may produce appreciably high decibel levels. Further characterization of the effect of humidifier design on SPLs and further elucidation of ambient sound levels associated with hearing risk are necessary before definitive conclusions and recommendations can be made. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

  7. Mercury exposure may suppress baseline corticosterone levels in juvenile birds.

    Science.gov (United States)

    Herring, Garth; Ackerman, Joshua T; Herzog, Mark P

    2012-06-05

    Mercury exposure has been associated with a wide variety of negative reproductive responses in birds, however few studies have examined the potential for chick impairment via the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis regulates corticosterone levels during periods of stress. We examined the relationship between baseline fecal corticosterone metabolite concentrations and mercury concentrations in down feathers of recently hatched (feathers (decreasing by 45% across the range of observed mercury concentrations) while accounting for stronger positive correlations between corticosterone concentrations and colony nest abundance and date. These results indicate that chronic mercury exposure may suppress baseline corticosterone concentrations in tern chicks and suggests that a juvenile bird's ability to respond to stress may be reduced via the downregulation of the HPA axis.

  8. Low level methylmercury exposure affects neuropsychological function in adults

    Directory of Open Access Journals (Sweden)

    Platt Illeane

    2003-06-01

    Full Text Available Abstract Background The neurotoxic effects of methylmercury (MeHg have been demonstrated in both human and animal studies. Both adult and fetal brains are susceptible to the effects of MeHg toxicity. However, the specific effects of adult exposures have been less well-documented than those of children with prenatal exposures. This is largely because few studies of MeHg exposures in adults have used sensitive neurological endpoints. The present study reports on the results of neuropsychological testing and hair mercury concentrations in adults (>17 yrs living in fishing communities of Baixada Cuiabana (Mato Grosso in the Pantanal region of Brazil. Methods A cross-sectional study was conducted in six villages on the Cuiaba River. Participants included 129 men and women older than 17 years of age. They were randomly selected in proportion to the age range and number of inhabitants in each village. Questionnaire information was collected on demographic variables, including education, occupation, and residence history. Mercury exposure was determined by analysis of hair using flameless atomic absorption spectrophotometry. The neurocognitive screening battery included tests from the Wechsler Memory Scale and the Wechsler Adult Intelligence Scale, Concentrated Attention Test of the Toulouse-Pierron Factorial Battery, the Manual Ability Subtests of the Tests of Mechanical Ability, and the Profile of Mood States. Results Mercury exposures in this population were associated with fish consumption. The hair mercury concentration in the 129 subjects ranged from 0.56 to 13.6 μg/g; the mean concentration was 4.2 ± 2.4 micrograms/g and the median was 3.7 μg/g. Hair mercury levels were associated with detectable alterations in performance on tests of fine motor speed and dexterity, and concentration. Some aspects of verbal learning and memory were also disrupted by mercury exposure. The magnitude of the effects increased with hair mercury concentration

  9. Cold exposure lowers energy expenditure at the cellular level.

    Science.gov (United States)

    Park, Seyeon; Chun, Sohyun; Kim, Danuh

    2013-06-01

    Mitochondrial function is intimately involved in various metabolic processes and is therefore essential to maintain cell viability. Of particular importance is the fact that mitochondrial membrane potential (ΔΨm ) is coupled with oxidative phosphorylation to drive adenosine triphosphate (ATP) synthesis. We have examined the effects of cold temperature stress on ΔΨm and the role of cold temperature receptor expression on ΔΨm . Human bronchial endothelial cell line, BEAS-2B, and human embryonic kidney, HEK293, cell line were transfected with the gene for cold temperature responsive receptor protein TRPM8 or TRPA1, and exposed to cold temperature. ΔΨm was monitored using 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazoyl carbocyanine iodide derivative (JC-10), a ΔΨm probe. While cold temperatures significantly increased ΔΨm and mitochondrial ATP levels in cells transfected with temperature responsive receptor TRPM8 or TRPA1, no change was noted in wild-type cells. Moreover, the change in ΔΨm and ATP level was a dynamic process. ΔΨm was raised to peak levels within 10 min of cold exposure, followed by a return to baseline levels at 30 min. Our findings suggest that cold temperature exposure increased mitochondrial ΔΨm via a mechanism involving cold temperature receptors. © 2013 International Federation for Cell Biology.

  10. Methylene chloride exposure and carboxyhemoglobin levels in cabinetmakers

    Science.gov (United States)

    Banjoko, Sunny O.; Sridhar Mynapelli, K. C.; Ogunkola, Isiah O.; Masheyi, Olatunde O.

    2007-01-01

    Methylene chloride (MeCl2) is a clear colorless volatile sweet smelling lipophilic solvent used as a constituent of wood vanishes and paints. Human exposure is mainly due to inhalation and its biotransformation by the hepatic mixed function oxidases (MFO) leads to formation of carbon monoxide (CO). Simultaneous exposure to MeCl2 and increased ambient CO results in undesirably increased carboxyhemoglobin (COHb) formation, which predisposes to carboxyhemoglobinaemia with the central nervous system as the primary target organ of toxicity. In this study, ambient CO levels were determined using a CO personal monitor in different pasts of Ibadan Nigeria and work place microenvironment of 50 Cabinet makers (test group) and 50 volunteer (control) in non-furniture making occupations. Mann Whitney U and Kruskaal Wallis were the statistical methods of analysis used. Questionnaires were administered to both groups carboxyhaemoglobin levels were determined in venous blood drawn from individuals in the two groups by differential spectrophotometric method. Ambient CO levels in Ibadan were observed to be between 4 and 52 ppm with a mean of 20 ppm. Work environment CO levels were significantly higher in test subjects than controls at 5.2 ± 1.08 ppm and 2.08 ± 0.91 ppm respectively (P 0.05). It is therefore imperative to substitute MeCl2 for safer chemicals in wood vanish and paints and the use of protective gas masks and adequate ventilation should be mandatory whenever MeCl2 is used. PMID:21938216

  11. Mind-sets, low-level exposures, and research

    International Nuclear Information System (INIS)

    Sagan, L.A.

    1993-01-01

    Much of our environmental policy is based on the notion that carcinogenic agents are harmful at even minuscule doses. From where does this thinking come? What is the scientific evidence that supports such policy? Moreover, why is the public willing to buy into this? Or is it the other way around: Has the scientific community bought into a paradigm that has its origins in public imagery? Or, most likely, are there interactions between the two? It is essential that we find out whether or not there are risks associated with low-level exposures to radiation. The author can see three obvious areas where the future depends on better information: The increasing radiation exposures resulting from the use of medical diagnostic and therapeutic practices need to be properly evaluated for safety; Environmental policies, which direct enormous resources to the reduction of small radiation exposures, needs to be put on a firmer scientific basis; The future of nuclear energy, dependent as it is on public acceptance, may well rely upon a better understanding of low-dose effects. Nuclear energy could provide an important solution of global warming and other possible environmental hazards, but will probably not be implemented as long as fear of low-dose radiation persists. Although an established paradigm has great resilience, it cannot resist the onslaught of inconsistent scientific observations or of the social value system that supports it. Only new research will enable us to determine if a paradigm shift is in order here

  12. Exposure levels to electromagnetic fields in usual operative situations

    International Nuclear Information System (INIS)

    Bemardi, C; Bemardi, T.; Testoni, G.; Zannoli, R.; Tubertini, O

    1997-01-01

    In the last few years, the whole population have been repeatedly solicited from media about the possible negative effects of E.M. Fields involved in all the social activities. This determinate the need of evaluations of the risks in different conditions, supported by accurate measurement protocols. This paper describes the procedures and the results of measurements in four different conditions, which involve the whole population and/or workers of a specific field. Results have been used both to increase the knowledge of the E.M. exposure levels and to evaluate the risks, with respect to the National Rules and Guidelines. (authors)

  13. First- and Second-level Bayesian Inference of Flow Resistivity of Sound Absorber and Room’s Influence

    DEFF Research Database (Denmark)

    Choi, Sang-Hyeon; Lee, Ikjin; Jeong, Cheol-Ho

    2016-01-01

    Sabine absorption coefficient is a widely used one deduced from reverberation time measurements via the Sabine equation. First- and second-level Bayesian analysis are used to estimate the flow resistivity of a sound absorber and the influences of the test chambers from Sabine absorption...... coefficients measured in 13 different reverberation chambers. The first-level Bayesian analysis is more general than the second-level Bayesian analysis. Sharper posterior distribution can be acquired by the second-level Bayesian analysis than the one by the first-level Bayesian analysis because more data...... are used to set more reliable prior distribution. The estimated room’s influences by the first- and the second-level Bayesian analyses are similar to the estimated results by the mean absolute error minimization....

  14. Expression of transcription factors after short-term exposure of Arabidopsis thaliana cell cultures to hyper-g, and to simulated and sounding rocket micro-g

    Science.gov (United States)

    Hampp, R.; Babbick, M.

    Previous microarray studies with cell cultures of Arabidopsis thaliana cv Columbia have shown responses in gene expression which were partly specific to exposure to microgravity sounding rocket experiment TEXUS In order to get access to early responses upon changes in gravitational fields we used exposure times as short as 2 min For this purpose we selected a range of genes which code for different groups of transcription factors WRKY ERF MYB MADS Samples were taken in 5-min clinorotation 2- and 3-dimensional hypergravity 8g and 2-min intervals sounding rocket experiment Amounts of transcripts were determined by quantitative RT PCR Most transcripts showed a significant transient change in content within a time frame of up to 30 min after changing the external gravitational field strength They could be grouped into 1 basic stress responses which occurred under all conditions 2 clinorotation-related effects which were either identical or opposite between 2D 60 rpm 4x10 -2 g and 3D clinorotation random positioning machine and 3 alterations specific to the microgravity exposure under sounding rocket conditions MAXUS The data are discussed in relation to gravitation-dependent signalling chains and with regard to the simulation of microgravity by means of clinorotation Supported by a grant from the Deutsches Zentrum f u r Luft- und Raumfahrt e V grant no 50 WB 0143

  15. What happens at very low levels of radiation exposure ? Are the low dose exposures beneficial ?

    International Nuclear Information System (INIS)

    Deniz, Dalji

    2006-01-01

    Full text: Radiation is naturally present in our environment and has been since the birth of this planet. The human population is constantly exposed to low levels of natural background radiation, primarily from environmental sources, and to higher levels from occupational sources, medical therapy, and other human-mediated events. Radiation is one of the best-investigated hazardous agents. The biological effects of ionizing radiation for radiation protection consideration are grouped into two categories: The deterministic and the stochastic ones. Deterministic radiation effects can be clinically diagnosed in the exposed individual and occur when above a certain t hreshold a n appropriately high dose is absorbed in the tissues and organs to cause the death of a large number of cells and consequently to impair tissue or organ functions early after exposure. A clinically observable biological effect (Acute Radiation Sendromes, ARS) occurs days to months after an acute radiation dose. Stochastic radiation effects are the chronic effects of radiation result from relatively low exposure levels delivered over long periods of time. These are sort of effects that might result from occupational exposure, or to the background exposure levels. Such late effects might be the development of malignant (cancerous) disease and of the hereditary consequences. These effects may be observed many years after the radiation exposure. There is a latent period between the initial radiation exposure and the development of the biological effect. For this reason, a stochastic effect is called a Linear or Zero-Threshold (LNT) Dose-Response Effect. There is a stochastic correlation between the number of cases of cancers or genetic defects developed inside a population and the dose received by the population at relatively large levels of radiation. These changes in gene activation seem to be able to modify the response of cells to subsequent radiation exposure, termed the a daptive response

  16. Underwater Sound Levels at a Wave Energy Device Testing Facility in Falmouth Bay, UK.

    Science.gov (United States)

    Garrett, Joanne K; Witt, Matthew J; Johanning, Lars

    2016-01-01

    Passive acoustic monitoring devices were deployed at FaBTest in Falmouth Bay, UK, a marine renewable energy device testing facility during trials of a wave energy device. The area supports considerable commercial shipping and recreational boating along with diverse marine fauna. Noise monitoring occurred during (1) a baseline period, (2) installation activity, (3) the device in situ with inactive power status, and (4) the device in situ with active power status. This paper discusses the preliminary findings of the sound recording at FabTest during these different activity periods of a wave energy device trial.

  17. The impact of a noise reduction quality improvement project upon sound levels in the open-unit-design neonatal intensive care unit.

    Science.gov (United States)

    Liu, W F

    2010-07-01

    To decrease measured sound levels in the neonatal intensive care unit through implementation of human factor and minor design modification strategies. Prospective time series. Two open-unit-design neonatal centers. Implementation of a coordinated program of noise reduction strategies did not result in any measurable improvement in levels of loudness or quiet. Two centers, using primarily human behavior noise reduction strategies, were unable to demonstrate measurable improvements in sound levels within the occupied open-unit-design neonatal intensive care unit.

  18. So small, so loud: extremely high sound pressure level from a pygmy aquatic insect (Corixidae, Micronectinae).

    Science.gov (United States)

    Sueur, Jérôme; Mackie, David; Windmill, James F C

    2011-01-01

    To communicate at long range, animals have to produce intense but intelligible signals. This task might be difficult to achieve due to mechanical constraints, in particular relating to body size. Whilst the acoustic behaviour of large marine and terrestrial animals has been thoroughly studied, very little is known about the sound produced by small arthropods living in freshwater habitats. Here we analyse for the first time the calling song produced by the male of a small insect, the water boatman Micronecta scholtzi. The song is made of three distinct parts differing in their temporal and amplitude parameters, but not in their frequency content. Sound is produced at 78.9 (63.6-82.2) SPL rms re 2.10(-5) Pa with a peak at 99.2 (85.7-104.6) SPL re 2.10(-5) Pa estimated at a distance of one metre. This energy output is significant considering the small size of the insect. When scaled to body length and compared to 227 other acoustic species, the acoustic energy produced by M. scholtzi appears as an extreme value, outperforming marine and terrestrial mammal vocalisations. Such an extreme display may be interpreted as an exaggerated secondary sexual trait resulting from a runaway sexual selection without predation pressure.

  19. So small, so loud: extremely high sound pressure level from a pygmy aquatic insect (Corixidae, Micronectinae.

    Directory of Open Access Journals (Sweden)

    Jérôme Sueur

    Full Text Available To communicate at long range, animals have to produce intense but intelligible signals. This task might be difficult to achieve due to mechanical constraints, in particular relating to body size. Whilst the acoustic behaviour of large marine and terrestrial animals has been thoroughly studied, very little is known about the sound produced by small arthropods living in freshwater habitats. Here we analyse for the first time the calling song produced by the male of a small insect, the water boatman Micronecta scholtzi. The song is made of three distinct parts differing in their temporal and amplitude parameters, but not in their frequency content. Sound is produced at 78.9 (63.6-82.2 SPL rms re 2.10(-5 Pa with a peak at 99.2 (85.7-104.6 SPL re 2.10(-5 Pa estimated at a distance of one metre. This energy output is significant considering the small size of the insect. When scaled to body length and compared to 227 other acoustic species, the acoustic energy produced by M. scholtzi appears as an extreme value, outperforming marine and terrestrial mammal vocalisations. Such an extreme display may be interpreted as an exaggerated secondary sexual trait resulting from a runaway sexual selection without predation pressure.

  20. Tributyltin exposure alters cytokine levels in mouse serum.

    Science.gov (United States)

    Lawrence, Shanieek; Pellom, Samuel T; Shanker, Anil; Whalen, Margaret M

    2016-11-01

    Tributyltin (TBT), a toxic environmental contaminant, has been widely utilized for various industrial, agricultural and household purposes. Its usage has led to a global contamination and its bioaccumulation in aquatic organisms and terrestrial mammals. Previous studies suggest that TBT has debilitating effects on the overall immune function of animals, rendering them more vulnerable to diseases. TBT (at concentrations that have been detected in human blood) alters secretion of inflammatory cytokines from human lymphocytes ex vivo. Thus, it is important to determine if specified levels of TBT can alter levels of cytokines in an in vivo system. Mice were exposed to biologically relevant concentrations of TBT (200, 100 or 25 nM final concentrations). The quantitative determination of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL2, IL5, IL7, IL12βp40, IL13, IL15, keratinocyte chemoattractant (KC), macrophage inflammatory protein 1β (MIP), MIP2 and regulated on activation normal T-cell-expressed and secreted (RANTES) was performed in mouse sera by MAGPIX analysis and Western blot. Results indicated alterations (both decreases and increases) in several cytokines. The pro-inflammatory cytokines IFNγ, TNFα, IL-1β, IL-2, IL5, IL12βp40 and IL-15 were altered as were the chemokines MIP-1 and RANTES and the anti-inflammatory cytokine IL-13. Increases in IFNγ and TNFα were seen in the serum of mice exposed to TBT for less than 24 h. Levels of IL1β, IL-12 βp40, IL-5 and IL-15 were also modulated in mouse serum, depending on the specific experiment and exposure level. IL-2 was consistently decreased in mouse serum when animals were exposed to TBT. There were also TBT-induced increases in MIP-1β, RANTES and IL-13. These results from human and murine samples clearly suggest that TBT exposures modulate the secretion inflammatory cytokines.

  1. The impact of architectural design upon the environmental sound and light exposure of neonates who require intensive care: an evaluation of the Boekelheide Neonatal Intensive Care Nursery.

    Science.gov (United States)

    Stevens, D C; Akram Khan, M; Munson, D P; Reid, E J; Helseth, C C; Buggy, J

    2007-12-01

    To evaluate the differences in environmental sound, illumination and physiological parameters in the Boekelheide Neonatal Intensive Care Unit (BNICU), which was designed to comply with current recommendations and standards, as compared with a conventional neonatal intensive care unit (CNICU). Prospectively designed observational study. Median sound levels in the unoccupied BNICU (37.6 dBA) were lower than the CNICU (42.1 dBA, P<0.001). Median levels of minimum (6.4 vs 48.4 lux, P<0.05) and maximum illumination (357 vs 402 lux, P<0.05) were lower in the BNICU. A group of six neonates delivered at 32 weeks gestation showed significantly less periodic breathing (14 vs 21%) and awake time (17.6 vs 29.3%) in the BNICU as compared to the CNICU. Light and sound were both significantly reduced in the BNICU. Care in the BNICU was associated with improved physiological parameters.

  2. Safety limit warning levels for the avoidance of excessive sound amplification to protect against further hearing loss.

    Science.gov (United States)

    Johnson, Earl E

    2017-11-01

    To determine safe output sound pressure levels (SPL) for sound amplification devices to preserve hearing sensitivity after usage. A mathematical model consisting of the Modified Power Law (MPL) (Humes & Jesteadt, 1991 ) combined with equations for predicting temporary threshold shift (TTS) and subsequent permanent threshold shift (PTS) (Macrae, 1994b ) was used to determine safe output SPL. The study involves no new human subject measurements of loudness tolerance or threshold shifts. PTS was determined by the MPL model for 234 audiograms and the SPL output recommended by four different validated prescription recommendations for hearing aids. PTS can, on rare occasion, occur as a result of SPL delivered by hearing aids at modern day prescription recommendations. The trading relationship of safe output SPL, decibel hearing level (dB HL) threshold, and PTS was captured with algebraic expressions. Better hearing thresholds lowered the safe output SPL and higher thresholds raised the safe output SPL. Safe output SPL can consider the magnitude of unaided hearing loss. For devices not set to prescriptive levels, limiting the output SPL below the safe levels identified should protect against threshold worsening as a result of long-term usage.

  3. Continuous Re-Exposure to Environmental Sound Cues During Sleep Does Not Improve Memory for Semantically Unrelated Word Pairs

    OpenAIRE

    Donohue, Kelly C.; Spencer, Rebecca M. C.

    2011-01-01

    Two recent studies illustrated that cues present during encoding can enhance recall if re-presented during sleep. This suggests an academic strategy. Such effects have only been demonstrated with spatial learning and cue presentation was isolated to slow wave sleep (SWS). The goal of this study was to examine whether sounds enhance sleep-dependent consolidation of a semantic task if the sounds are re-presented continuously during sleep. Participants encoded a list of word pairs in the evening...

  4. Evaluation of noise pollution level based upon community exposure and response data

    Science.gov (United States)

    Edmiston, R. D.

    1972-01-01

    The results and procedures are reported from an evaluation of noise pollution level as a predictor of annoyance, based on aircraft noise exposure and community response data. The measures of noise exposure presented include composite noise rating, noise exposure forecast, noise and number index. A proposed measure as a universal noise exposure measure for noise pollution level (L sub NP) is discussed.

  5. Radiation exposure rate and liquid level measurement inside a high level liquid waste (HLLW) storage tank

    International Nuclear Information System (INIS)

    Sur, B.; Yue, S.; Thekkevarriam, A.

    2007-01-01

    An instrument based on an inexpensive, small silicon diode has been developed and used to measure, for the first time, the gamma radiation exposure rate profile inside a 6.4 mm diameter reentrant thermo-well tube, immersed in the highly radioactive liquid solution in an HLLW storage tank. The measurement agrees with previous calculations of exposure rate, and provides confirmation for safe and effective radiation work plans and material selection for investigations and remediation of the storage tank facility. The measured radiation exposure rate profile is also used to confirm that the position of tank internal structures have not changed because of aging and corrosion, and to obtain, within a few mm, the level of liquid inside the tank. (author)

  6. Galvanizing industry: evaluation of exposure levels using biomonitors

    International Nuclear Information System (INIS)

    Menezes, Maria Angela de B.C.; Sabino, Claudia de V.S.; Amaral, Angela Maria; Mattos, Silvania V. de M.; S. Filho, Serafim; Maia, Elene Cristina P.

    1999-01-01

    In Brazil, statistical surveys concerning occupational diseases refer to accidents and damages. The surveys do not refer to the occupational diseases developed through long exposures to hazardous work conditions, involving physical risk and toxic chemical substances. The Program of Medical Control of Occupational Health determines the Maximum Biological Levels Allowed and the Values of Normality References. But concerning metal and toxic inorganic, values of only few elements are established. In Belo Horizonte and surroundings areas, which is an important industrial centre in the country, there are different industries distributed over various areas. There are about 80 galvanizing industries which are responsible for the majority of the metal contamination hospitalities. A preliminary sampling was performed in order to conduct a survey of the exposures to elements related to occupational diseases in galvanizing industry. The preliminary results for toxic and non-toxic elements obtained using hair and fingernails as biomonitors are shown. The K 0 parametric neutron activation analysis method was applied and the elements determined were: Ag, Al, Au, Cl, Co, Cr, Cu, Fe, I, Mn, Na, Ti, V, Ta, and Zn. (author)

  7. Guidelines on radiation exposure levels for emergency situations

    International Nuclear Information System (INIS)

    1992-07-01

    This document provides guidelines for establishing occupational exposure levels for undertaking actions in emergency situations resulting from a nuclear accident. There are three categories of exposed persons identifiable in relation to the circumstances under which they receive exposures resulting from an accident: (i) emergency workers exposed while undertaking urgent corrective actions; (ii) workers exposed while undertaking subsequent remedial actions, including countermeasures to protect the public; (iii) persons living in an environment contaminated by a nuclear accident. Although no dose limit can be easily stated for the first category, doses should be kept below 0.5 Sv. For the second category, normal dose limits would apply with a maximum of 0.05 Sv in a given year; however, in some circumstances where a few key experts are required doses up to 0.1 Sv could be permitted. For the third category the approach to be taken is to apply the ICRP's concept of dose constraint - a fraction of the worker's dose limit, but above the public dose limit. (L.L.) (6 refs., tab.)

  8. Galvanizing industry: evaluation of exposure levels using biomonitors

    Energy Technology Data Exchange (ETDEWEB)

    Menezes, Maria Angela de B.C.; Sabino, Claudia de V.S.; Amaral, Angela Maria [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil); Mattos, Silvania V. de M. [FUNED, Belo Horizonte, MG (Brazil). Div. de Bromatologia e Toxicologia; S. Filho, Serafim [Secretaria Municipal de Saude de Belo Horizonte, MG (Brazil). Coordenacao de Saude do Trabalhador; Maia, Elene Cristina P. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Quimica

    1999-11-01

    In Brazil, statistical surveys concerning occupational diseases refer to accidents and damages. The surveys do not refer to the occupational diseases developed through long exposures to hazardous work conditions, involving physical risk and toxic chemical substances. The Program of Medical Control of Occupational Health determines the Maximum Biological Levels Allowed and the Values of Normality References. But concerning metal and toxic inorganic, values of only few elements are established. In Belo Horizonte and surroundings areas, which is an important industrial centre in the country, there are different industries distributed over various areas. There are about 80 galvanizing industries which are responsible for the majority of the metal contamination hospitalities. A preliminary sampling was performed in order to conduct a survey of the exposures to elements related to occupational diseases in galvanizing industry. The preliminary results for toxic and non-toxic elements obtained using hair and fingernails as biomonitors are shown. The K{sub 0} parametric neutron activation analysis method was applied and the elements determined were: Ag, Al, Au, Cl, Co, Cr, Cu, Fe, I, Mn, Na, Ti, V, Ta, and Zn. (author) 8 refs., 3 figs., 2 tabs.; e-mail: menezes at urano.cdtn.br

  9. Assessing risks from occupational exposure to low-level radiation

    International Nuclear Information System (INIS)

    Gilbert, E.S.

    1989-06-01

    Currently, several epidemiological studies of workers who have been exposed occupationally to radiation are being conducted. These include workers in the United States, Great Britain, and Canada, involved in the production of both defense materials and nuclear power. A major reason for conducting these studies is to evaluate possible adverse health effects that may have resulted because of the radiation exposure received. The general subject of health effects resulting from low levels of radiation, including these worker studies, has attracted the attention of various news media, and has been the subject of considerable controversy. These studies provide a good illustration of certain other aspects of the statistician's role; namely, communication and adequate subject matter knowledge. A competent technical job is not sufficient if these other aspects are not fulfilled

  10. Radon gas exposure levels in some selected areas in Egypt

    International Nuclear Information System (INIS)

    Ali, E.M.; Taha, T.M.; Gomaa, M.A.; El-Hussein, A.M.; Ahmed, A.A.

    2005-01-01

    During a summer season of 2003, the atmospheric concentrations of radon gas were measured indoor every one-hour for twenty-four hour measurements in some selected areas, using Pylon-AB4. Two hundreds and forty samples were monitored to determine the concentration of radon gas at each location using high-efficiency Lucas type continuous passive cell. The average values of radon gas concentration were taken in three time intervals 6.00:18.00, 18.00:6.00 and whole day. The average values of indoor radon gas of two locations using three time intervals were 4.82±0.63, 9±0.71 and 6.9±0.33 and 9.6±0.23, 11.82±0.42 and 9.37±0.7 Bq/m /h. respectively. The exposure levels were within the ICRP and EPA recommendations

  11. Tributyltin Exposure Alters Cytokine Levels in Mouse Serum

    Science.gov (United States)

    Lawrence, Shanieek; Pellom, Samuel T.; Shanker, Anil; Whalen, Margaret M.

    2016-01-01

    Tributyltin (TBT), a toxic environmental contaminant, has been widely utilized for various industrial, agricultural and household purposes. Its usage has led to a global contamination and its bioaccumulation in aquatic organisms and terrestrial mammals. Previous studies suggest that TBT has debilitating effects on the overall immune function of animals, rendering them more vulnerable to diseases. TBT (at concentrations that have been detected in human blood) alters secretion of inflammatory cytokines from human lymphocytes ex vivo. Thus, it is important to determine if specified levels of TBT can alter levels of cytokines in an in vivo system. Mice were exposed to biologically relevant concentrations of TBT (200, 100 or 25 nM final concentrations). The quantitative determination of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL2, IL5, IL7, IL12βp40, IL13, IL15, KC, MIP1β, MIP2 and RANTES was performed in mouse sera by MAGPIX analysis and Western blot. Results indicated alterations (both decreases and increases) in several cytokines. The pro-inflammatory cytokines IFNγ, TNFα, IL-1β, IL-2, IL5, IL12βp40, and IL-15 were altered as were the chemokines MIP-1 and RANTES and the anti-inflammatory cytokine IL-13. Increases in IFNγ and TNFα were seen in serum of mice exposed to TBT for less than 24 hr. IL1-β, IL-12βp40, IL-5 and IL-15 were also modulated in mouse serum depending on the specific experiment and the exposure concentration. IL-2 was consistently decreased in mouse serum when animals were exposed to TBT. There were also TBT-induced increases in MIP-1β, RANTES, and IL-13. These results from human and murine samples clearly suggest that TBT exposures modulate the secretion inflammatory cytokines. PMID:27602597

  12. Music exposure differentially alters the levels of brain-derived neurotrophic factor and nerve growth factor in the mouse hypothalamus.

    Science.gov (United States)

    Angelucci, Francesco; Ricci, Enzo; Padua, Luca; Sabino, Andrea; Tonali, Pietro Attilio

    2007-12-18

    It has been reported that music may have physiological effects on blood pressure, cardiac heartbeat, respiration, and improve mood state in people affected by anxiety, depression and other psychiatric disorders. However, the physiological bases of these phenomena are not clear. Hypothalamus is a brain region involved in the regulation of body homeostasis and in the pathophysiology of anxiety and depression through the modulation of hypothalamic-pituitary-adrenal (HPA) axis. Hypothalamic functions are also influenced by the presence of the neurotrophins brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), which are proteins involved in the growth, survival and function of neurons in the central nervous system. The aim of this study was to investigate the effect of music exposure in mice on hypothalamic levels of BDNF and NGF. We exposed young adult mice to slow rhythm music (6h per day; mild sound pressure levels, between 50 and 60 dB) for 21 consecutive days. At the end of the treatment mice were sacrificed and BDNF and NGF levels in the hypothalamus were measured by enzyme-linked immunosorbent assay (ELISA). We found that music exposure significantly enhanced BDNF levels in the hypothalamus. Furthermore, we observed that music-exposed mice had decreased NGF hypothalamic levels. Our results demonstrate that exposure to music in mice can influence neurotrophin production in the hypothalamus. Our findings also suggest that physiological effects of music might be in part mediated by modulation of neurotrophins.

  13. Global levels of radiation exposure: Latest international findings

    International Nuclear Information System (INIS)

    Gonzalez, A.J.

    1993-01-01

    The radiation exposure of the world's population has recently been reviewed by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). UNSCEAR has reconfirmed that the normal operation of all peaceful nuclear installations contributes insignificantly to the global exposure to radiation. Even taking into account all the nuclear accidents to date (including Chernobyl), the additional exposure would be equivalent to only about 20 days of natural exposure. Military uses of nuclear energy have committed the world to most of the radiation exposure caused by human activities

  14. Nickel exposure and plasma levels of biomarkers for assessing oxidative stress in nickel electroplating workers.

    Science.gov (United States)

    Tsao, Yu-Chung; Gu, Po-Wen; Liu, Su-Hsun; Tzeng, I-Shiang; Chen, Jau-Yuan; Luo, Jiin-Chyuan John

    2017-07-01

    The mechanism of nickel-induced pathogenesis remains elusive. To examine effects of nickel exposure on plasma oxidative and anti-oxidative biomarkers. Biomarker data were collected from 154 workers with various levels of nickel exposure and from 73 controls. Correlations between nickel exposure and oxidative and anti-oxidative biomarkers were determined using linear regression models. Workers with a exposure to high nickel levels had significantly lower levels of anti-oxidants (glutathione and catalase) than those with a lower exposure to nickel; however, only glutathione showed an independent association after multivariable adjustment. Exposure to high levels of nickel may reduce serum anti-oxidative capacity.

  15. Sound algorithms

    OpenAIRE

    De Götzen , Amalia; Mion , Luca; Tache , Olivier

    2007-01-01

    International audience; We call sound algorithms the categories of algorithms that deal with digital sound signal. Sound algorithms appeared in the very infancy of computer. Sound algorithms present strong specificities that are the consequence of two dual considerations: the properties of the digital sound signal itself and its uses, and the properties of auditory perception.

  16. Derived reference levels for prenatal exposure in a radiological emergency

    International Nuclear Information System (INIS)

    Nuccetelli, C.; Risica, S.; Rogani, A.

    2002-01-01

    After the Chernobyl accident many countries renewed their radiological emergency plans, also considering the possibility of over boundary accidents. This has been set out by the 96/29/Euratom Directive (Council Directive, 1996), which states that E ach Member State shall ensure that account is taken of the fact that radiological emergencies may occur in connection with practices on or outside its territory and affect it . Moreover, after September 11, 2001, the need to prepare emergency plans for possible terroristic attacks became evident and these plans are now being worked out in many countries for intervention in case of biological, chemical and/or radiological risk. In the event of radiological emergency, all decisions to be taken are based on possible doses to critical groups (European Commission, 1997), which are the population groups most at risk. These critical groups are, in most cases, infants or children, given that dose coefficients for these age groups are generally higher than for adults. However, a new ICRP Recommendation (ICRP, 2001) has recently been published that gives dose coefficients for embryo/foetus due to intake by the mother, by inhalation or ingestion, of 31 radionuclides. Also as a result of the revaluation in the last years of the possible health effects of prenatal exposure to ionising radiation (see e.g. the review in P. Fattibene et al., 1999), the consequences for the embryo/foetus of a possible radiological emergency connected to a nuclear plant and to possible dispersion of Depleted Uranium (DU) in the environment are analysed and discussed in this paper. For the former type of accident, Derived Intervention Levels (DILs) are calculated for prenatal exposure due to acute inhalation by the mother (female member of the public) and an assessment is performed of ingestion doses for the offspring resulting from consumption of foodstuffs by the mother of which 10% of the annual consumption is contaminated at the maximum levels

  17. Comparison of the Level of Substance P and Neurokinin A in Gingival Crevicular Fluid of Sound and Symptomatic Carious Primary Teeth by ELISA

    Directory of Open Access Journals (Sweden)

    Alireza Heidari

    2017-10-01

    Full Text Available Objectives: Pulpal inflammation is often associated with odontogenic pain. Dental pulp is abundantly innervated with sensory fibers encompassing neuropeptides. Neurokinin A (NKA and substance P (SP are important neuropeptides in the dental pulp that can cause neurogenic inflammation. Since no previous study has assessed dental pulp neuropeptides in children, this study aimed to compare the level of NKA and SP in gingival crevicular fluid (GCF of sound and symptomatic carious primary teeth.Materials and Methods: Samples of GCF were obtained of 20 sound and 20 painful carious primary teeth. Enzyme-linked immunosorbent assay (ELISA was used to quantify neuropeptides in GCF. Data were analyzed using paired t-test, ANOVA, Kolmogorov-Smirnov test and correlation coefficient test.Results: A significant difference was noted in the level of NKA in GCF of painful and sound teeth (2.23 pg/ml in painful, and 1.84 pg/ml in sound teeth, P<0.05. The difference between the two groups regarding SP was not significant (2.23 pg/ml in painful, and 2.02 pg/ml in sound teeth, P>0.05.Conclusions: The results showed that the level of NKA and SP was higher in GCF of painful teeth compared to that of sound teeth. This difference was statistically significant with regard to NKA. Thus, these neuropeptides can serve as indicators for pathological activities in teeth with symptomatic irreversible pulpitis.

  18. Ecological effects of exposure to enhanced levels of ionizing radiation.

    Science.gov (United States)

    Geras'kin, Stanislav A

    2016-10-01

    Irradiation of plants and animals can result in disruption of ecological relationships between the components of ecosystems. Such effects may act as triggers of perturbation and lead to consequences that may differ essentially from expected ones based on effects observed at the organismal level. Considerable differences in ecology and niches occupied by different species lead to substantial differences in doses of ionizing radiation absorbed by species, even when they all are present in the same environment at the same time. This is especially evident for contamination with α-emitting radionuclides. Radioactive contamination can be considered an ecological factor that is able to modify the resistance in natural populations. However, there are radioecological situations when elevated radioresistance does not evolve or persist. The complexity and non-linearity of the structure and functioning of ecosystems can lead to unexpected consequences of stress effects, which would appear harmless if they were assessed within the narrower context of organism-based traditional radioecology. Therefore, the use of ecological knowledge is essential for understanding responses of populations and ecosystems to radiation exposure. Integration of basic ecological principles in the design and implementation of radioecological research is essential for predicting radiation effects under rapidly changing environmental conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Sound level of environmental music and drinking behavior: a field experiment with beer drinkers.

    Science.gov (United States)

    Guéguen, Nicolas; Jacob, Céline; Le Guellec, Hélène; Morineau, Thierry; Lourel, Marcel

    2008-10-01

    It had been found that environmental music was associated with an increase in alcohol consumption. The presence versus absence of music, high versus slow tempo and the different styles of environmental music is associated with different level of alcohol consumption. However, the effect of the level of the environmental music played in a bar still remained in question. Forty male beer drinkers were observed in a bar. According to a random distribution, patrons were exposed to the usual level of environmental music played in 2 bars where the experiment was carried out or were exposed to a high level. The results show that high level volume led to increase alcohol consumption and reduced the average amount of time spent by the patrons to drink their glass. The impact of environmental music on consumption was discussed and the "arousal" hypothesis and the negative effect of loud music on social interaction were used to explain our results.

  20. Effects of Sound on the Behavior of Wild, Unrestrained Fish Schools.

    Science.gov (United States)

    Roberts, Louise; Cheesman, Samuel; Hawkins, Anthony D

    2016-01-01

    To assess and manage the impact of man-made sounds on fish, we need information on how behavior is affected. Here, wild unrestrained pelagic fish schools were observed under quiet conditions using sonar. Fish were exposed to synthetic piling sounds at different levels using custom-built sound projectors, and behavioral changes were examined. In some cases, the depth of schools changed after noise playback; full dispersal of schools was also evident. The methods we developed for examining the behavior of unrestrained fish to sound exposure have proved successful and may allow further testing of the relationship between responsiveness and sound level.

  1. Application of physiologically based pharmacokinetic modeling in setting acute exposure guideline levels for methylene chloride.

    NARCIS (Netherlands)

    Bos, Peter Martinus Jozef; Zeilmaker, Marco Jacob; Eijkeren, Jan Cornelis Henri van

    2006-01-01

    Acute exposure guideline levels (AEGLs) are derived to protect the human population from adverse health effects in case of single exposure due to an accidental release of chemicals into the atmosphere. AEGLs are set at three different levels of increasing toxicity for exposure durations ranging from

  2. Sound recordings of road maintenance equipment on the Lincoln National Forest, New Mexico

    Science.gov (United States)

    D. K. Delaney; T. G. Grubb

    2004-01-01

    The purpose of this pilot study was to record, characterize, and quantify road maintenance activity in Mexican spotted owl (Strix occidentalis lucida) habitat to gauge potential sound level exposure for owls during road maintenance activities. We measured sound levels from three different types of road maintenance equipment (rock crusherlloader,...

  3. Noise exposure levels for musicians during rehearsal and performance times.

    Science.gov (United States)

    McIlvaine, Devon; Stewart, Michael; Anderson, Robert

    2012-03-01

    The purpose of this study was to determine daily noise doses and 8-hour time weighted averages for rock band musicians, crew members, and spectators during a typical rehearsal and performance using both Occupational Safety and Health Administration (OSHA) and National Institute of Occupational Safety and Health (NIOSH) measurement criteria. Personal noise dosimetry was completed on five members of a rock band during one 2-hr rehearsal and one 4-hr performance. Time-weighted averages (TWA) and daily dose values were calculated using both OSHA and NIOSH criteria and compared to industry guidelines for enrollment in hearing conservation programs and the use of hearing protection devices. TWA values ranged from 84.3 to 90.4 dBA (OSHA) and from 90.0 to 96.4 dBA (NIOSH) during the rehearsal. The same values ranged from 91.0 to 99.7 dBA (OSHA) and 94.0 to 102.8 dBA (NIOSH) for the performance. During the rehearsal, daily noise doses ranged from 45.54% to 106.7% (OSHA) and from 317.74% to 1396.07% (NIOSH). During the performance, doses ranged from 114.66% to 382.49% (OSHA) and from 793.31% to 5970.15% (NIOSH). The musicians in this study were exposed to dangerously high levels of noise and should be enrolled in a hearing conservation programs. Hearing protection devices should be worn, especially during performances. The OSHA measurement criteria yielded values significantly more conservative than those produced by NIOSH criteria. Audiologists should counsel musician-patients about the hazards of excessive noise (music) exposure and how to protect their hearing.

  4. 16 CFR 1500.47 - Method for determining the sound pressure level produced by toy caps.

    Science.gov (United States)

    2010-01-01

    ... level produced by toy caps. 1500.47 Section 1500.47 Commercial Practices CONSUMER PRODUCT SAFETY... horizontal plane with a distance of 25 centimeters between the diaphragm of the microphone and the position... the trigger are each respectively closest to and in the same horizontal plane with the microphone. (3...

  5. Paleo relief study of insular shelf electric sounding in Amarillo level basin Rivera distric in Uruguay

    International Nuclear Information System (INIS)

    Perrin, J.

    1983-01-01

    In the framework of the Uranium project the geophysical team composed by BRGM and DINAMIGE members have carried out a study of insular shelf morphology. It was a sedimentary basin level in the middle of the Isla Cristalina. The following topics were developed: geographical location, geologic framework, developed works and materials, methods and results

  6. Validation of the Predicted Circumferential and Radial Mode Sound Power Levels in the Inlet and Exhaust Ducts of a Fan Ingesting Distorted Inflow

    Science.gov (United States)

    Koch, L. Danielle

    2012-01-01

    Fan inflow distortion tone noise has been studied computationally and experimentally. Data from two experiments in the NASA Glenn Advanced Noise Control Fan rig have been used to validate acoustic predictions. The inflow to the fan was distorted by cylindrical rods inserted radially into the inlet duct one rotor chord length upstream of the fan. The rods were arranged in both symmetric and asymmetric circumferential patterns. In-duct and farfield sound pressure level measurements were recorded. It was discovered that for positive circumferential modes, measured circumferential mode sound power levels in the exhaust duct were greater than those in the inlet duct and for negative circumferential modes, measured total circumferential mode sound power levels in the exhaust were less than those in the inlet. Predicted trends in overall sound power level were proven to be useful in identifying circumferentially asymmetric distortion patterns that reduce overall inlet distortion tone noise, as compared to symmetric arrangements of rods. Detailed comparisons between the measured and predicted radial mode sound power in the inlet and exhaust duct indicate limitations of the theory.

  7. The Philosophy, Theoretical Bases, and Implementation of the AHAAH Model for Evaluation of Hazard from Exposure to Intense Sounds

    Science.gov (United States)

    2018-04-01

    being associated with susceptibility— middle ear muscle responsiveness, sex , chemical exposure, prior exposure to noise, eye color, inner ear protective...temporal bones by use of a video measuring system. Acta Otolarngol. 1987;103:87–95. Hamernik RP, Ahroon WA, Patterson JH, Jr. Threshold recovery functions

  8. Radiation in complex exposure situations. Assessing health risks at low levels from concomitant exposures to radiation and chemicals

    International Nuclear Information System (INIS)

    Hornhardt, S.; Jung, T.; Burkart, W.

    2000-01-01

    Health effects from exposures to ionizing radiation are in general the result of complex multi-step reaction chains involving changes and responses on the level of molecules, cells, tissues and organisms. In environmental low dose exposure situations ionizing radiation only contributes a small fraction to the life-long attack on DNA by other exogenous and endogenous genotoxins. Nevertheless, efforts to assess and quantify deleterious effects at low exposure levels are directed mainly towards radiation as a single isolated agent, and rarely towards the concomitant presence of other natural and anthropogenic toxicants. Only these combined exposures may lead to observable health risk effects. In addition they might differ from those expected from simple addition of the individual risks due to interaction. The existing data base on combined effects is rudimentary, mainly descriptive and rarely covers exposure ranges large enough to make direct inferences to present day low dose exposure situations. Therefore, any risk assessment will have to consider the question whether combined effects, i.e. interaction between two or more agents will influence the health outcome from specific exposure situations in such a way that predictions derived from simple standard exposure situations would have to be revised. In view of the multitude of possible interactions between the large number of potentially harmful agents in the human environment, descriptive approaches will have to be supplemented by the use of mechanistic models for critical health endpoints such as cancer. Agents will have to be grouped depending on their physical or chemical mode of action at the molecular and cellular level, to generalize and predict the outcome of combined exposures at low exposure levels and the possibility of interactions. (author)

  9. Multichannel sound reinforcement systems at work in a learning environment

    Science.gov (United States)

    Malek, John; Campbell, Colin

    2003-04-01

    Many people have experienced the entertaining benefits of a surround sound system, either in their own home or in a movie theater, but another application exists for multichannel sound that has for the most part gone unused. This is the application of multichannel sound systems to the learning environment. By incorporating a 7.1 surround processor and a touch panel interface programmable control system, the main lecture hall at the University of Michigan Taubman College of Architecture and Urban Planning has been converted from an ordinary lecture hall to a working audiovisual laboratory. The multichannel sound system is used in a wide variety of experiments, including exposure to sounds to test listeners' aural perception of the tonal characteristics of varying pitch, reverberation, speech transmission index, and sound-pressure level. The touch panel's custom interface allows a variety of user groups to control different parts of the AV system and provides preset capability that allows for numerous system configurations.

  10. The Effect of Microphone Placement on Interaural Level Differences and Sound Localization Across the Horizontal Plane in Bilateral Cochlear Implant Users.

    Science.gov (United States)

    Jones, Heath G; Kan, Alan; Litovsky, Ruth Y

    2016-01-01

    This study examined the effect of microphone placement on the interaural level differences (ILDs) available to bilateral cochlear implant (BiCI) users, and the subsequent effects on horizontal-plane sound localization. Virtual acoustic stimuli for sound localization testing were created individually for eight BiCI users by making acoustic transfer function measurements for microphones placed in the ear (ITE), behind the ear (BTE), and on the shoulders (SHD). The ILDs across source locations were calculated for each placement to analyze their effect on sound localization performance. Sound localization was tested using a repeated-measures, within-participant design for the three microphone placements. The ITE microphone placement provided significantly larger ILDs compared to BTE and SHD placements, which correlated with overall localization errors. However, differences in localization errors across the microphone conditions were small. The BTE microphones worn by many BiCI users in everyday life do not capture the full range of acoustic ILDs available, and also reduce the change in cue magnitudes for sound sources across the horizontal plane. Acute testing with an ITE placement reduced sound localization errors along the horizontal plane compared to the other placements in some patients. Larger improvements may be observed if patients had more experience with the new ILD cues provided by an ITE placement.

  11. Equivalent threshold sound pressure levels (ETSPL) for Sennheiser HDA 280 supra-aural audiometric earphones in the frequency range 125 Hz to 8000 Hz

    DEFF Research Database (Denmark)

    Poulsen, Torben; Oakley, Sebastian

    2009-01-01

    Hearing threshold sound pressure levels were measured for the Sennheiser HDA 280 audiometric earphone. Hearing thresholds were measured for 25 normal hearing test subjects at the 11 audiometric test frequencies from 125 Hz to 8000 Hz. Sennheiser HDA 280 is a supra-aural earphone that may be seen...... as a substitute for the classical Telephonics TDH 39. The results are given as the Equivalent Threshold Sound Pressure Level, ETSPL, measured in an acoustic coupler specified in IEC 60318-3. The results are in good agreement with an independent investigation from PTB, Braunschweig, Germany. From acoustic...

  12. Polychlorinated biphenyl sources, environmental levels, and exposures in school buildings

    Science.gov (United States)

    Background: Building materials and components containing polychlorinated biphenyls (PCBs) were used in some U.S. school buildings until the late 1970s and may be present today. There is limited information on source factors and occupant exposures. Methods: Analysis of PCBs in mat...

  13. Occupational exposure to diesel engine exhaust and serum cytokine levels

    NARCIS (Netherlands)

    Dai, Yufei; Ren, Dianzhi; Bassig, Bryan A.; Vermeulen, Roel; Hu, Wei; Niu, Yong; Duan, Huawei; Ye, Meng; Meng, Tao; Xu, Jun; Li, Ping; Shen, Meili; Yang, Jufang; Fu, Wei; Meliefste, Kees; Silverman, Debra T.; Rothman, Nathaniel; Lan, Qing; Zheng, Yuxin

    The International Agency for Research on Cancer has classified diesel engine exhaust (DEE) as a human lung carcinogen. Given that inflammation is suspected to be an important underlying mechanism of lung carcinogenesis, we evaluated the relationship between DEE exposure and the inflammatory response

  14. Foley Sounds vs Real Sounds

    DEFF Research Database (Denmark)

    Trento, Stefano; Götzen, Amalia De

    2011-01-01

    This paper is an initial attempt to study the world of sound effects for motion pictures, also known as Foley sounds. Throughout several audio and audio-video tests we have compared both Foley and real sounds originated by an identical action. The main purpose was to evaluate if sound effects...

  15. Effects of Listening to Music versus Environmental Sounds in Passive and Active Situations on Levels of Pain and Fatigue in Fibromyalgia.

    Science.gov (United States)

    Mercadíe, Lolita; Mick, Gérard; Guétin, Stéphane; Bigand, Emmanuel

    2015-10-01

    In fibromyalgia, pain symptoms such as hyperalgesia and allodynia are associated with fatigue. Mechanisms underlying such symptoms can be modulated by listening to pleasant music. We expected that listening to music, because of its emotional impact, would have a greater modulating effect on the perception of pain and fatigue in patients with fibromyalgia than listening to nonmusical sounds. To investigate this hypothesis, we carried out a 4-week study in which patients with fibromyalgia listened to either preselected musical pieces or environmental sounds when they experienced pain in active (while carrying out a physical activity) or passive (at rest) situations. Concomitant changes of pain and fatigue levels were evaluated. When patients listened to music or environmental sounds at rest, pain and fatigue levels were significantly reduced after 20 minutes of listening, with no difference of effect magnitude between the two stimuli. This improvement persisted 10 minutes after the end of the listening session. In active situations, pain did not increase in presence of the two stimuli. Contrary to our expectations, music and environmental sounds produced a similar relieving effect on pain and fatigue, with no benefit gained by listening to pleasant music over environmental sounds. Copyright © 2015 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  16. Long-term monitoring program: Evaluating chronic exposure of harlequin ducks and sea otters to lingering Exxon Valdez Oil in Western Prince William Sound

    Science.gov (United States)

    Esler, Daniel N.; Bowen, Lizabeth; Miles, A. Keith; Ballachey, Brenda E.; Bodkin, James L.

    2015-01-01

    We found that average cytochrome P4501A induction (as measured by EROD activity) during March 2014 was not elevated in wintering harlequin ducks captured in areas of Prince William Sound oiled by the 1989 Exxon Valdez oil spill, relative to those captured in unoiled areas. This result is consistent with findings from March 2013. We interpret these findings to indicate that exposure of harlequin ducks to residual Exxon Valdez oil abated within 24 years after the original spill. Results from preceding sampling in 2011 indicated that EROD activity was elevated in harlequin ducks in oiled relative to unoiled areas, although the magnitude of elevation was lower than in previous years (1998-2009), suggesting that the rate or intensity of exposure was diminishing by 2011. The data presented in this report add to a growing body of literature indicating that persistence of oil in the environment, and exposure of wildlife to that oil, can occur over much longer time frames than previously assumed.

  17. Lack of physiological responses to hydrocarbon accumulation by Mytilus trossulus after 3-4 years chronic exposure to spilled Exxon Valdez crude oil in Prince William Sound

    International Nuclear Information System (INIS)

    Thomas, R.E.; Brodersen, C.; Carls, M.G.; Babcock, M.; Rice, S.D.

    1999-01-01

    Mussels, Mytilus trossulus, were sampled in 1992 and 1993 from beaches in Prince William Sound that had been oiled by the Exxon Valdez spill of March, 1989. At some of the oiled beaches, mussels were collected from beds overlying oiled sediments, and from bedrock adjacent to these beds. Mussels were also collected from beaches within the Sound that had not been impacted by the spill. Polynuclear aromatic hydrocarbon (PAH) concentrations in mussel tissue, physiological responses (byssal thread production, condition index, clearance rate, and glycogen content), were determined for each group of mussels. Total PAH concentrations in mussel tissue ranged from 0 to 6 μg g -1 , and were significantly greater in mussels from oiled beds than those from reference beds. No significant differences were noted in byssal thread production, condition index, clearance rate, or glycogen content between oiled sample sites and reference sites. The lack of physiological response was surprising because mussels in this study were chronically exposed to PAH for 3-4 years, and none of the physiological responses measured appeared to be affected by that exposure. The lack of a physiological response suggests that chronically exposed mussels may develop a physiological tolerance to PAH, but we recognize that these measures may not have been sensitive enough to discriminate response from background noise. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  18. The calculation of maximum permissible exposure levels for laser radiation

    International Nuclear Information System (INIS)

    Tozer, B.A.

    1979-01-01

    The maximum permissible exposure data of the revised standard BS 4803 are presented as a set of decision charts which ensure that the user automatically takes into account such details as pulse length and pulse pattern, limiting angular subtense, combinations of multiple wavelength and/or multiple pulse lengths, etc. The two decision charts given are for the calculation of radiation hazards to skin and eye respectively. (author)

  19. Nanogold – Biological effects and occupational exposure levels

    Directory of Open Access Journals (Sweden)

    Anna Maria Świdwińska-Gajewska

    2017-08-01

    Full Text Available Nanogold has different properties and biological activity compared to metallic gold. It can be applied in many fields, such as medicine, laboratory diagnostics and electronics. Studies on laboratory animals show that nanogold can be absorbed by inhalation and ingestion. It can penetrate deep into the epidermis and dermis, but there is no evidence that it is absorbed through the skin. Gold nanoobjects accumulate mainly in the liver and spleen, but they can also reach other internal organs. Nanogold can cross the blood–brain and blood–placenta barriers. Toxicokinetics of nanogold depends on the particle size, shape and surface charge. In animals exposure to gold nanoparticles via inhalation induces slight changes in the lungs. Exposure to nanogold by the oral route does not cause adverse health effects in rodents. In animals after injection of gold nanoobjects changes in the liver and lungs were observed. Nanogold induced genotoxic effects in cells, but not in animals. No adverse effects on the fetus or reproduction were found. There are no carcinogenicity studies on gold nanoparticles. The mechanism of toxicity may be related to the interaction of gold nanoobjects with proteins and DNA, and it leads to the induction of oxidative stress and genetic material damage. The impact of nanostructures on human health has not yet been fully understood. The person, who works with nanomaterials should exercise extreme caution and apply existing recommendations on the evaluation of nanoobjects exposure. The risk assessment should be the basis for taking appropriate measures to limit potential exposure to nanometals, including nanogold. Med Pr 2017;68(4:545–556

  20. Simulation of design dependent failure exposure levels for CMOS ICs

    International Nuclear Information System (INIS)

    Kaul, N.; Bhuva, B.L.; Rangavajjhala, V.; van der Molen, H.; Kerns, S.E.

    1990-01-01

    The total dose exposure of CMOS ICs introduces bias-dependent parameter shifts in individual devices. The bias dependency of individual parameter shifts of devices cause different designs to behave differently under identical testing conditions. This paper studies the effect of design and bias on the radiation tolerance of ICs and presents an automated design tool that produces different designs for a logic function, and presents important parameters of each design to circuit designer for trade off analysis

  1. Biomonitoring of organophosphate exposure of pesticide sprayers and comparison of exposure levels with other population groups in Thessaly (Greece).

    Science.gov (United States)

    Koureas, Michalis; Tsakalof, Andreas; Tzatzarakis, Manolis; Vakonaki, Elena; Tsatsakis, Aristidis; Hadjichristodoulou, Christos

    2014-02-01

    To evaluate the exposure of different population groups in Thessaly (Greece) to organophosphate pesticides (OPs) and investigate the dependence of exposure levels on pesticide application practices, personal protective and hygienic measures taken. For the exposure assessment, four dialkyl phosphate (DAP) metabolites of organophosphate pesticides were quantified in spot urine samples of 77 pesticide sprayers, 75 residents of the studied agricultural area non-involved in agricultural activities and 112 urban residents who served as a control group. Structured questionnaires were used to record demographic characteristics, pesticide application parameters and protective measures taken. Univariate and multivariate analysis of the obtained cross-sectional data was performed to identify potential risk factors associated with biomarker levels. It was found that total DAP median level in the sprayers' group was 24.9 μg/g creatinine (IQR: 13.0-42.1), while the rural and urban residents had significantly lower (p<0.001) levels of 11.3 μg/g creatinine (IQR: 5.3-18.7) and 11.9 μg/g creatinine (IQR: 6.3-20.3), respectively. In sprayers who had recently applied an OP pesticide (n=28), the median levels of DAP metabolites were 31.8 μg/g creatinine (IQR: 22.3-117.2). Logistic regression analysis showed that the use of full body coveralls while handling and spraying pesticides was significantly associated with lower DAP levels (OR 4.05, 95% CI 1.22 to 13.46). Also, changing clothes immediately after accidental contamination of clothing with pesticide amounts was found to be significantly associated with lower exposure levels (OR 4.04, CI 1.05 to 15.57). Our study findings confirm the increased exposure to OPs in pesticide sprayers and underline the importance of protective measures especially those that focus on dermal exposure mitigation.

  2. Equivalent threshold sound pressure levels for Sennheiser HDA 200 earphone and Etymotic Research ER-2 insert earphone in the frequency range 125 Hz to 16 kHz

    DEFF Research Database (Denmark)

    Han, Loc A; Poulsen, Torben

    1998-01-01

    Equivalent Threshold Sound Pressure Levels (ETSPLs) have been determined for the Sennheiser HDA 200 earphone and the Etymotic Research ER-2insert earphone. Thirty-one young normal-hearing test subjects participated and the thresholds were determined for all recommended frequencies in thefrequency...

  3. Technique for estimating the sound power level radiated by pneumatic rock drills and the evaluation of a CSIR prototype rock drill with engineering noise controls

    CSIR Research Space (South Africa)

    Kovalchik, PG

    2009-05-01

    Full Text Available and the radiation patterns in octave and 1/3 octave bands. Overall sound power level is also determined. This paper also reports the results obtained by using this procedure to evaluate a SECO S215 standard production drill and a CSIR Miningtek prototype rock drill...

  4. The dissimilar time course of temporary threshold shifts and reduction of inhibition in the inferior colliculus following intense sound exposure

    NARCIS (Netherlands)

    Heeringa, A. N.; van Dijk, P.

    Excessive noise exposure is known to produce an auditory threshold shift, which can be permanent or transient in nature. Recent studies showed that noise-induced temporary threshold shifts are associated with loss of synaptic connections to the inner hair cells and with cochlear nerve degeneration,

  5. Acute Exposure Guideline Levels (AEGLs) for Time Varying Toxic Plumes

    Science.gov (United States)

    2014-09-12

    loading rates between the density values given as Arho(b-1,k) and Arho(b,k). The line labeled ‘ extrap .’above b = 1 in Table 3 records the derived...exposure times and an inverse quadratic law for densities lower than 8.26 mg/m3. The line labeled ‘ extrap .’ at the bottom of the table gives the...6 (labeled “ extrap .” above) are simply duplicated from the adjacent band b = 5. This exponent is also used to define the lowest density value Brho

  6. Standing operating procedures for developing acute exposure guideline levels for hazardous chemicals

    National Research Council Canada - National Science Library

    National Research Council (U.S.). Subcommittee on Acute Exposure Guideline Levels

    2001-01-01

    ... Exposure Guideline Levels for Hazardous Chemicals Subcommittee on Acute Exposure Guideline Levels Committee on Toxicology Board on Environmental Studies and Toxicology Commission on Life Sciences National Research Council NATIONAL ACADEMY PRESS Washington, D.C. i Copyrightthe cannot be not from book, paper however, version for formatting, origina...

  7. Respiratory health effects of exposure to low levels of airborne endotoxin - a systematic review.

    Science.gov (United States)

    Farokhi, Azadèh; Heederik, Dick; Smit, Lidwien A M

    2018-02-08

    Elevated endotoxin levels have been measured in ambient air around livestock farms, which is a cause of concern for neighbouring residents. There is clear evidence that occupational exposure to high concentrations of airborne endotoxin causes respiratory inflammation, respiratory symptoms and lung function decline. However, health effects of exposure to low levels of endotoxin are less well described. The aim of this systematic review is to summarize published associations between exposure to relatively low levels of airborne endotoxin and respiratory health endpoints. Studies investigating respiratory effects of measured or modelled exposure to low levels of airborne endotoxin (average effects of exposure to low levels of endotoxin on respiratory symptoms and lung function. However, considerable heterogeneity existed in the outcomes of the included studies and no overall estimate could be provided by meta-analysis to quantify the possible relationship. Instead, a best evidence synthesis was performed among studies examining the exposure-response relationship between endotoxin and respiratory outcomes. Significant exposure-response relationships between endotoxin and symptoms and FEV 1 were shown in several studies, with no conflicting findings in the studies included in the best evidence synthesis. Significantly different effects of endotoxin exposure were also seen in vulnerable subgroups (atopics and patients with broncho-obstructive disease) and smokers. Respiratory health effects of exposure to low levels of airborne endotoxin (health effects, especially in vulnerable subgroups of the population.

  8. Exposure to low levels of hydrogen sulfide : symptoms, sensory function, and cognitive performance

    International Nuclear Information System (INIS)

    Fiedler, N.; Kipen, H.; Lioy, P.; Zhang, J.; Weisel, C.

    2003-01-01

    Petroleum refineries, kraft paper mills, and coke ovens are some of the sources of hydrogen sulfide exposure. In 1987, the World Health Organization (WHO) recommended an ambient exposure standard of .003 ppm for odor and .01 ppm for eye irritation. In communities with high exposure levels, health effects have been documented as being headaches, eye and nasal symptoms, coughs, breathlessness and decreased psychomotor performance. Refinery workers in some jurisdictions around the world have been subjected to higher exposure levels. This report presents results of clinical studies on the neurobehavioral effects in rats. The tasks of memory and learning in rats parallels those in humans. A pilot exposure study examined the health effects of controlled exposures to 3 concentrations of hydrogen sulfide (.05, .50, and 5 ppm). It was concluded that changes in neurobehavioral measurements can be directly associated with exposure and dose-response. 25 figs

  9. [Hexavalent chromium pollution and exposure level in electroplating workplace].

    Science.gov (United States)

    Zhang, Xu-hui; Zhang, Xuan; Yang, Zhang-ping; Jiang, Cai-xia; Ren, Xiao-bin; Wang, Qiang; Zhu, Yi-min

    2012-08-01

    To investigate the pollution of hexavalent chromium in the electroplating workplace and screen the biomarkers of chromium exposure. Field occupational health investigation was conducted in 25 electroplating workplaces. 157 electroplating workers and 93 healthy unexposed controls were recruited. The epidemiological information was collected with face to face interview. Chromium in erythrocytes was determined by graphite furnace atomic absorption spectrophotometer. The median of short-term exposure concentration of chromium in the air at electroplating workplace was 0.06 mg/m(3) (median) and ranging from 0.01 (detect limit) to 0.53 mg/m(3)). The median concentration of Cr (VI) in erythrocytes in electroplating workers was 4.41 (2.50 ∼ 5.29) µg/L, which was significantly higher than that in control subjects [1.54 (0.61 ∼ 2.98) µg/L, P electroplating workers and control subjects, except for the subjects of age less than 30 years old (P = 0.11). There was hexavalent chromium pollution in electroplating workplace. Occupational hazards prevention measures should be taken to control the chromium pollution hazards.

  10. Imagining Sound

    DEFF Research Database (Denmark)

    Grimshaw, Mark; Garner, Tom Alexander

    2014-01-01

    We make the case in this essay that sound that is imagined is both a perception and as much a sound as that perceived through external stimulation. To argue this, we look at the evidence from auditory science, neuroscience, and philosophy, briefly present some new conceptual thinking on sound...... that accounts for this view, and then use this to look at what the future might hold in the context of imagining sound and developing technology....

  11. Mapping of radio frequency electromagnetic field exposure levels in outdoor environment and comparing with reference levels for general public health.

    Science.gov (United States)

    Cansiz, Mustafa; Abbasov, Teymuraz; Kurt, M Bahattin; Celik, A Recai

    2018-03-01

    In this study, radio frequency electromagnetic field exposure levels were measured on the main streets in the city center of Diyarbakır, Turkey. Measured electric field levels were plotted on satellite imagery of Diyarbakır and were compared with exposure guidelines published by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Exposure measurements were performed in dense urban, urban and suburban areas each day for 7 consecutive days. The measurement system consisted of high precision and portable spectrum analyzer, three-axis electric field antenna, connection cable and a laptop which was used to record the measurement samples as a data logger. The highest exposure levels were detected for two places, which are called Diclekent and Batıkent. It was observed that the highest instantaneous electric field strength value for Batıkent was 7.18 V/m and for Diclekent was 5.81 V/m. It was statistically determined that the main contributor band to the total exposure levels was Universal Mobile Telecommunications System band. Finally, it was concluded that all measured exposure levels were lower than the reference levels recommended by ICNIRP for general public health.

  12. In situ exposure of herring embryos in Prince William Sound two years after the Exxon Valdez oil spill

    International Nuclear Information System (INIS)

    Kocan, R.; Brown, E.; Baker, T.

    1995-01-01

    In order to evaluate long-term residual toxicity, artificially spawned Pacific herring (Clupea pallasl) embryos were deployed at 5 oiled and 5 unoiled sites in Prince William Sound two years after the Exxon Valdez oil spill. Embryos were exposed at 1.5 m and 4.5 m below mean low water for 8--10 d post fertilization. The embryos were then retrieved and transported to the laboratory for hatching and evaluation under controlled conditions, Endpoints were (1) embryo survival, (2) live hatch, (3) deformed larvae and (4) larval dry weight. The oiled sites produced significantly (P < 0.01) more deformed larvae (63.3%) than did the unoiled sites (51.3%), but there was a lower hatching success at the unoiled sites which resulted in no overall difference in normal live larvae produced between oiled and unoiled sites. The mean dry weight of newly hatched larvae from the oiled sites (78 microg/larva) was significantly lower than those from the unoiled sites (97 microg/larva) at all depths (P < 0.01). Increased larval deformities and reduced hatching weight is consistent with what has been reported by several investigators for herring larvae experimentally and naturally exposed to petroleum hydrocarbons. Based on the data, there appeared to be differences between the previously oiled and unoiled sites relative to herring development, but it is not clear whether this was due to residual oil effects or parental effects

  13. Exposure to asbestos and levels of selected tumor biomarkers

    International Nuclear Information System (INIS)

    Krajewska, B.; Lutz, W.; Pilacik, B.

    1996-01-01

    Occupational exposure to asbestos, a recognised carcinogen, poses a risk for such diseases as asbestosis, lung cancer and mesothelioma. It is thought that asbestos fibres may damage microphages which undergo neoplastic transformation as well as fibroblast, while partial phagocytosis may generate free oxygenic radicals which induce cellular peroxidase and damage macromolecules. Neoplastic biomarkers such as tissue polypeptide antigen (TPA) or carcinoembryonic antigen (CEA) are now used for this purpose. The aim of the work was to identify workers exposed to asbestos in the population, especially high risk groups neoplastic diseases and to evaluate the usefulness of TPA and CEA determinations. The study covered a group of asbestos exposed workers (n = 4000 and the control group of workers (n = 135) nonexposed to any toxic factor at work. Age, exposure time, smoking habits and workpost characteristics were taken into consideration in the analysis of the results. It was revealed that in 38 persons exposed to asbestos, TPA values were above the concentration limit set on the basis of studies carried out in the control group, and elevated CEA values applied to 13 persons. Significant differences between groups under study were found in the proportion of pathological TPA values. Such a relationship was not observed in regard to CEA values. In the exposed group the results also indicated an evident effect of age and exposure time on the number of persons with TPA values above concentration limit. The effect of smoking on the frequency of pathological TPA values was also clear-cut in workers exposed to asbestos. Taking into account three types of employment, the analysis indicated significant differences in TPA values between blue collar workers and other personnel; and between white collar workers and other personnel. This means a similar percentage of pathological TPA values in the group of blue collar and white collar workers. The study carried out allowed to identify

  14. Secondhand smoke exposure and serum cotinine levels among current smokers in the USA.

    Science.gov (United States)

    Lindsay, Ryan P; Tsoh, Janice Y; Sung, Hai-Yen; Max, Wendy

    2016-03-01

    Secondhand smoke (SHS) likely provides additional exposure to nicotine and toxins for smokers, but has been understudied. Our objective was to determine whether SHS exposure among smokers yields detectable differences in cotinine levels compared with unexposed smokers at the population level. Using the US National Health and Nutrition Examination Survey (NHANES) for the years 1999-2012, we compared serum cotinine levels of 4547 current adult cigarette smokers stratified by self-reported SHS exposure sources (home and/or work) and smoking intensity. A weighted multivariable linear regression model determined the association between SHS exposure and cotinine levels among smokers. Smokers with SHS exposure at home (43.8%) had higher cotinine levels (β=0.483, p≤0.001) compared with those with no SHS exposure at home after controlling for the number of cigarettes smoked per day and number of days smoked in the previous 5 days, survey year, age, gender and education. Smokers with SHS exposure at work (20.0%) did not have significantly higher cotinine levels after adjustment. The adjusted geometric mean cotinine levels of light smokers (1-9 cigarettes per day) with no SHS exposure, exposure at work only, home only, and both home and work were 52.0, 62.7, 67.2, 74.4 ng/mL, respectively, compared with 219.4, 220.9, 255.2, 250.5 ng/mL among moderate/heavy smokers (≥10 cigarettes per day). Smokers living in residences where others smoke inside the home had significantly higher cotinine levels than smokers reporting no SHS exposure, regardless of individual smoking intensity. Future research should target the role that SHS exposure may have in nicotine dependence, cessation outcomes and other health impacts among smokers. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  15. Childhood cancer after low-level intrauterine exposure to radiation

    Energy Technology Data Exchange (ETDEWEB)

    Wakeford, Richard [BNFL, Risley, Warrington, Cheshire (United Kingdom)]. E-mail: R.Wakeford@bnfl.com; Little, Mark P. [Department of Epidemiology and Public Health, Imperial College of Science, Technology and Medicine, London (United Kingdom)

    2002-09-01

    Case-control studies of childhood cancer and foetal exposure to diagnostic x-rays suggest that doses as small as 10 mSv increase the risk of cancer to a detectable extent. A comparison of the risk coefficient derived from the largest such study with that obtained from the Japanese atomic bomb survivors irradiated in utero (average dose, {approx}300 mGy) shows that, once all sources of uncertainty are taken into account, these risk estimates are not incompatible. The absence of a discernible variation in the risk per unit dose over this dose range is consistent with a linear dose-response. However, uncertainties are such that definitive conclusions on the shape of the dose-response at low doses cannot be drawn from this epidemiological evidence alone. Nonetheless, the evidence does suggest that the risk is not zero at doses of the order of 10 mSv. (author)

  16. Development of computer program ENAUDIBL for computation of the sensation levels of multiple, complex, intrusive sounds in the presence of residual environmental masking noise

    Energy Technology Data Exchange (ETDEWEB)

    Liebich, R. E.; Chang, Y.-S.; Chun, K. C.

    2000-03-31

    The relative audibility of multiple sounds occurs in separate, independent channels (frequency bands) termed critical bands or equivalent rectangular (filter-response) bandwidths (ERBs) of frequency. The true nature of human hearing is a function of a complex combination of subjective factors, both auditory and nonauditory. Assessment of the probability of individual annoyance, community-complaint reaction levels, speech intelligibility, and the most cost-effective mitigation actions requires sensation-level data; these data are one of the most important auditory factors. However, sensation levels cannot be calculated by using single-number, A-weighted sound level values. This paper describes specific steps to compute sensation levels. A unique, newly developed procedure is used, which simplifies and improves the accuracy of such computations by the use of maximum sensation levels that occur, for each intrusive-sound spectrum, within each ERB. The newly developed program ENAUDIBL makes use of ERB sensation-level values generated with some computational subroutines developed for the formerly documented program SPECTRAN.

  17. Implicit learning of predictable sound sequences modulates human brain responses at different levels of the auditory hierarchy

    Directory of Open Access Journals (Sweden)

    Françoise eLecaignard

    2015-09-01

    Full Text Available Deviant stimuli, violating regularities in a sensory environment, elicit the Mismatch Negativity (MMN, largely described in the Event-Related Potential literature. While it is widely accepted that the MMN reflects more than basic change detection, a comprehensive description of mental processes modulating this response is still lacking. Within the framework of predictive coding, deviance processing is part of an inference process where prediction errors (the mismatch between incoming sensations and predictions established through experience are minimized. In this view, the MMN is a measure of prediction error, which yields specific expectations regarding its modulations by various experimental factors. In particular, it predicts that the MMN should decrease as the occurrence of a deviance becomes more predictable. We conducted a passive oddball EEG study and manipulated the predictability of sound sequences by means of different temporal structures. Importantly, our design allows comparing mismatch responses elicited by predictable and unpredictable violations of a simple repetition rule and therefore departs from previous studies that investigate violations of different time-scale regularities. We observed a decrease of the MMN with predictability and interestingly, a similar effect at earlier latencies, within 70 ms after deviance onset. Following these pre-attentive responses, a reduced P3a was measured in the case of predictable deviants. We conclude that early and late deviance responses reflect prediction errors, triggering belief updating within the auditory hierarchy. Beside, in this passive study, such perceptual inference appears to be modulated by higher-level implicit learning of sequence statistical structures. Our findings argue for a hierarchical model of auditory processing where predictive coding enables implicit extraction of environmental regularities.

  18. Ambient and at-the-ear occupational noise exposure and serum lipid levels

    DEFF Research Database (Denmark)

    Arlien-Søborg, Mai C; Schmedes, Astrid S; Stokholm, Z A

    2016-01-01

    -the-ear occupational noise exposure and serum levels of total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, and triglycerides when accounting for well-established predictors of lipid levels. METHODS: This cross-sectional study included 424 industrial workers and 84 financial......OBJECTIVES: Occupational and residential noise exposure has been related to increased risk of cardiovascular disease. Alteration of serum lipid levels has been proposed as a possible causal pathway. The objective of this study was to investigate the relation between ambient and at...... workers to obtain contrast in noise exposure levels. They provided a serum sample and wore portable dosimeters that every 5-s recorded ambient noise exposure levels during a 24-h period. We extracted measurements obtained during work and calculated the full-shift mean ambient noise level. For 331 workers...

  19. Population-Level Exposure to Particulate Air Pollution during Active Travel: Planning for Low-Exposure, Health-Promoting Cities.

    Science.gov (United States)

    Hankey, Steve; Lindsey, Greg; Marshall, Julian D

    2017-04-01

    Providing infrastructure and land uses to encourage active travel (i.e., bicycling and walking) are promising strategies for designing health-promoting cities. Population-level exposure to air pollution during active travel is understudied. Our goals were a ) to investigate population-level patterns in exposure during active travel, based on spatial estimates of bicycle traffic, pedestrian traffic, and particulate concentrations; and b ) to assess how those exposure patterns are associated with the built environment. We employed facility-demand models (active travel) and land use regression models (particulate concentrations) to estimate block-level ( n = 13,604) exposure during rush-hour (1600-1800 hours) in Minneapolis, Minnesota. We used the model-derived estimates to identify land use patterns and characteristics of the street network that are health promoting. We also assessed how exposure is correlated with indicators of health disparities (e.g., household income, proportion of nonwhite residents). Our work uses population-level rates of active travel (i.e., traffic flows) rather than the probability of walking or biking (i.e., "walkability" or "bikeability") to assess exposure. Active travel often occurs on high-traffic streets or near activity centers where particulate concentrations are highest (i.e., 20-42% of active travel occurs on blocks with high population-level exposure). Only 2-3% of blocks (3-8% of total active travel) are "sweet spots" (i.e., high active travel, low particulate concentrations); sweet spots are located a ) near but slightly removed from the city-center or b ) on off-street trails. We identified 1,721 blocks (~ 20% of local roads) where shifting active travel from high-traffic roads to adjacent low-traffic roads would reduce exposure by ~ 15%. Active travel is correlated with population density, land use mix, open space, and retail area; particulate concentrations were mostly unchanged with land use. Public health officials and

  20. Radiation cancer, safety standards and current levels of exposure

    International Nuclear Information System (INIS)

    Mole, R.H.

    1976-01-01

    Cancer can be induced by radiation in any tissue where cancer occurs naturally. The observation that antenatal diagnostic radiography causes a small but definite increase in childhood cancer is as good evidence as could be expected in support of the scientific expectation that there would be no threshold of dose for carcinogenesis. A linear relation between radiation dose and frequency of induced cancer is a necessary assumption for a system of radiological protection but is not necessarily a reasonable basis for realistic assessments of cancer risk. Indeed there are radiobiological and epidemiological reasons to the contrary. If the linear hypothesis is accepted then at the present time in the UK the routine practice of medicine is of about 2 orders of magnitude more important in causing cancer than environmental pollution by discharge of radio-activity. The acceptability of radiation safety standards for occupational exposure may be justified by comparison of radiation cancer risks with risks from fatal accidents in the safer industries. The acceptability of the corresponding standards for members of the public seems to require more public discussion of the concept of negligible risk. Emotional reactions to uncontrolled releases of radio-activity are based at least in part on a failure to appreciate the hypothesis of linearity

  1. Effective exposure level and diagnostic performance in endodontic radiography

    International Nuclear Information System (INIS)

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

    1983-01-01

    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

  2. Why Do People Like Loud Sound? A Qualitative Study.

    Science.gov (United States)

    Welch, David; Fremaux, Guy

    2017-08-11

    Many people choose to expose themselves to potentially dangerous sounds such as loud music, either via speakers, personal audio systems, or at clubs. The Conditioning, Adaptation and Acculturation to Loud Music (CAALM) Model has proposed a theoretical basis for this behaviour. To compare the model to data, we interviewed a group of people who were either regular nightclub-goers or who controlled the sound levels in nightclubs (bar managers, musicians, DJs, and sound engineers) about loud sound. Results showed four main themes relating to the enjoyment of loud sound: arousal/excitement, facilitation of socialisation, masking of both external sound and unwanted thoughts, and an emphasis and enhancement of personal identity. Furthermore, an interesting incidental finding was that sound levels appeared to increase gradually over the course of the evening until they plateaued at approximately 97 dBA Leq around midnight. Consideration of the data generated by the analysis revealed a complex of influential factors that support people in wanting exposure to loud sound. Findings were considered in terms of the CAALM Model and could be explained in terms of its principles. From a health promotion perspective, the Social Ecological Model was applied to consider how the themes identified might influence behaviour. They were shown to influence people on multiple levels, providing a powerful system which health promotion approaches struggle to address.

  3. Environmental tobacco smoke exposure among non-smoking waiters: measurement of expired carbon monoxide levels

    Directory of Open Access Journals (Sweden)

    Ronaldo Laranjeira

    2000-07-01

    Full Text Available CONTEXT: Exposure to environmental tobacco smoke is a health risk that is of concern to patrons and of particular concern to employees of restaurants and bars. OBJECTIVE: To assess environmental tobacco smoke exposure (using expired carbon monoxide levels in non-smoking waiters before and after a normal day's shift and to compare pre-exposure levels with non-smoking medical students. DESIGN: An observational study. SETTING: Restaurants with more than 50 tables or 100 places in São Paulo. SUBJECTS: 100 non-smoking restaurant waiters and 100 non-smoking medical students in São Paulo, Brazil. MAIN MEASUREMENTS: Levels of expired carbon monoxide, measured with a Smokerlyser (Bedfont EC 50 Scientific, before and after a normal day's work. RESULTS: Waiters' pre-exposure expired carbon monoxide levels were similar to those of medical students, but after a mean of 9 hours exposure in the workplace, median levels more than doubled (2.0 ppm vs. 5.0 ppm, P <0.001. Post-exposure carbon monoxide levels were correlated with the number of tables available for smokers (Kendall's tau = 0.2, P <0.0001. CONCLUSIONS: Exposure to environmental tobacco smoke is the most likely explanation for the increase in carbon monoxide levels among these non-smoking waiters. These findings can be used to inform the ongoing public health debate on passive smoking.

  4. Personal carbon monoxide exposures of preschool children in Helsinki, Finland: levels and determinants

    Science.gov (United States)

    Alm, S.; Mukala, K.; Jantunen, M. J.

    Personal CO exposures of 194 preschool children were measured with personal exposure monitors during a 24 week sampling period from fall 1990 to spring 1991 in Helsinki, Finland. Arithmetic mean of the maximum 1 and 8 h exposure levels were 6.0 and 3.3 mg m -3. The then Finnish ambient air quality guideline values for 1/8 h maximum CO level (30/10 mg m -3) were exceeded in 2/4% of the children's daily maximum 1/8 h exposure levels. Gas stove at home, parents, especially mother, smoking in the home, and living in high rise buildings — reflecting higher local population and traffic density — increased the children's CO exposures. The presence of a fireplace in the home was associated with decreased CO exposures. Father's high education reduced the children's CO exposure while mother's education level had no significant effect. The peak (15 min) exposure levels of the children commuting to day care center by car or bus were higher than those of the children who walked or came by bike.

  5. Blood Lead Levels And Potental Environmental Exposures Among ...

    African Journals Online (AJOL)

    p = 0.439). Low risk parental occupation (p = 0.001) and. Kales sourced from the market/kiosks (p = 0.001) were significantly associated with BLL ≥ 10ug/dl. Soil lead levels (Soil Pb) ranged from 3,000 to 90,000ug/kg, which was very high ...

  6. Esophageal acid exposure decreases intraluminal baseline impedance levels

    NARCIS (Netherlands)

    Kessing, Boudewijn F.; Bredenoord, Albert J.; Weijenborg, Pim W.; Hemmink, Gerrit J. M.; Loots, Clara M.; Smout, A. J. P. M.

    2011-01-01

    Intraluminal baseline impedance levels are determined by the conductivity of the esophageal wall and can be decreased in gastroesophageal reflux disease (GERD) patients. The aim of this study was to investigate the baseline impedance in GERD patients, on and off proton pump inhibitor (PPI), and in

  7. Establishing the level of exposure to radon gas in dwellings

    International Nuclear Information System (INIS)

    Karupa, Jackson Uakaningirua

    2016-04-01

    The main source of natural internal irradiation of man is radon and its decay products. In this study, the radon concentration levels in selected dwellings in Erongo region, Swakopmund, Namibia will be estimated using passive or active radon detector. The primary objective of the study is to measure and establish radon levels in selected dwellings in Erongo region, Swakopmund of Namibia. Measurements will be carried out for the period of twelve months and after three months period the detectors will be exchanged for laboratory analysis. The results obtained from the study will reveal the concentration of radon in most of the selected dwellings in Erongo region, Swakopmund, Namibia. Once Radon level is measured or identified, the results with data from work done in other environments in Africa and elsewhere will be compared. In case of high radon concentrations in dwelling, the occupants will be advised to ensure good ventilation practices as cost effective means of mitigation of indoor radon gas level in the area. (au)

  8. The relationship between blood lead levels and occupational exposure in a pregnant population

    OpenAIRE

    Osmel La-Llave-León; José Manuel Salas Pacheco; Sergio Estrada Martínez; Eloísa Esquivel Rodríguez; Francisco X. Castellanos Juárez; Ada Sandoval Carrillo; Angélica María Lechuga Quiñones; Fernando Vázquez Alanís; Gonzalo García Vargas; Edna Madai Méndez Hernández; Jaime Duarte Sustaita

    2016-01-01

    Background Pregnant women exposed to lead are at risk of suffering reproductive damages, such as miscarriage, preeclampsia, premature delivery and low birth weight. Despite that the workplace offers the greatest potential for lead exposure, there is relatively little information about occupational exposure to lead during pregnancy. This study aims to assess the association between blood lead levels and occupational exposure in pregnant women from Durango, Mexico. Methods A cross-sectional stu...

  9. Associations between cadmium exposure and circulating levels of sex hormones in postmenopausal women

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Imran; Engström, Annette; Vahter, Marie [Institute of Environmental Medicine, Karolinska Institutet, 171 77 Stockholm (Sweden); Skerfving, Staffan; Lundh, Thomas [Division of Occupational and Environmental Medicine, University Hospital, Lund (Sweden); Lidfeldt, Jonas [Department of Community Health, Malmö University Hospital, Malmö (Sweden); Samsioe, Göran [Department of Gynecology and Obstetrics, University Hospital, Lund (Sweden); Halldin, Krister [Institute of Environmental Medicine, Karolinska Institutet, 171 77 Stockholm (Sweden); Åkesson, Agneta, E-mail: agneta.akesson@ki.se [Institute of Environmental Medicine, Karolinska Institutet, 171 77 Stockholm (Sweden)

    2014-10-15

    Recent epidemiological as well as in vivo and in vitro studies collectively suggest that the metalloestrogen cadmium (Cd) could be a potential risk factor for hormone-related cancers in particularly breast cancer. Assessment of the association between Cd exposure and levels of endogenous sex hormones is of pivotal importance, as increased levels of such have been associated with a higher risk of breast cancer in postmenopausal women. The present study investigated the perceived relationship (multivariable-adjusted linear regression analyses) between Cd exposure [blood Cd (B-Cd) and urinary Cd (U-Cd)], and serum levels of androstenedione, testosterone, estradiol, and sex-hormone binding globulin (SHBG), in 438 postmenopausal Swedish women without hormone replacement therapy (HRT). A significant positive association between B-Cd (median 3.4 nmol/L) and serum testosterone levels, as well as a significant inverse association between B-Cd and serum estradiol levels and with the estradiol/testosterone ratio were encountered. However, U-Cd (median 0.69 nmol/mmol creatinine) was inversely associated with serum estradiol levels only. Our data may suggest that Cd interferes with the levels of testosterone and estradiol in postmenopausal women, which might have implications for breast cancer risk. - Highlights: • Low level cadmium exposure may interfere with the levels of steroid hormones. • Cadmium exposure was associated with increased serum testosterone concentrations. • Cadmium exposure was associated with decreased estradiol/testosterone ratio. • Cadmium exposure may have implications for breast-cancer promotion.

  10. Accommodating brightness and exposure levels in densitometry of stained polyacrylamide electrophoresis gels

    International Nuclear Information System (INIS)

    Tan, Han Yen; Ng, Tuck Wah; Liew, Oi Wah

    2010-01-01

    Flatbed scanner densitometers can be operated under various illumination and recording exposure levels. In this work, we show that optical density measurement accuracy, sensitivity, and stability of stained polyacrylamide electrophoresis gel densitometry are crucially dependent on these two factors (brightness and exposure level), notwithstanding that the source is monochromatic, spatially uniform, and the measurements are made using an accurately calibrated step wedge in tandem. We further outline a method to accommodate the intensity deviations over a range of illumination and exposure levels in order to maintain sensitivity and repeatability in the computed optical densities. Comparisons were also made with results from a commercial densitometer.

  11. Low-Level Effects of VX Vapor Exposure on Pupil Diameter and Cholinesterase Levels in Rats

    National Research Council Canada - National Science Library

    Benton, B. J; Crosier, R. B; Sommerville, D. R; Jakubowski, E. M., Jr; Anthony, J. S., Jr; Scotto, J; Hulet, S. W; Whalley, C. E; Crouse, C. L; Matson, K. L; Miller, D. B

    2004-01-01

    .... Results show that the median effective dosages (ECt sub 50) for miosis are approximately an order of magnitude lower than the calculated ECt sub 50 values for both GB and GF at each of the 3 exposure durations...

  12. Cognitive consequences of novelty and familiarity: how mere exposure influences level of construal

    NARCIS (Netherlands)

    Förster, J.

    2009-01-01

    Two experiments examine whether frequency of exposure influences level of construal. Using subliminal presentation, participants were exposed to neutral, unknown letters 0, 5, 15, or 40 times, and a typical mere exposure effect was found on evaluation. However, we hypothesized and showed in

  13. Quality assurance of external exposure measurement for national survey of environmental natural radioactive level

    International Nuclear Information System (INIS)

    Yue Qingyu

    1995-01-01

    This paper summarizes the quality assurance work of external exposure measurement for national survey of environmental natural radioactive level. It mainly introduces instrumentation used in external exposure measurement and its properties, the measurement results of three times of national in-site intercomparison, and in-site sample check results of measurement results from 29 provinces, cities and autonomous regions and Wuhan, Baotou cities

  14. Overview of the hazards of low-level exposure to radiation

    International Nuclear Information System (INIS)

    Ritenour, E.R.

    1984-01-01

    In this chapter the authors are concerned with low-level radiation, doses of ionizing radiations that are ten to thousands of times smaller than those required to contract ARS. Low-level radiation may be defined as an absorbed dose of 10 rem or less delivered over a short period of time. A larger dose delivered over a long period of time, for instance, 50 rem in 10 years, may also be considered low level. The definition is purposely loose so as to cover a wide variety of sources of radiation exposure, such as natural background (100 mrem/year) occupational exposures (<5 rem/year), and medical applications, such as diagnostic radiography (<1 rem). Low-level radiation exposure does not produce ARS. The health effects that may be of concern in regard to low-level radiation are its long-term sequelae. Studies of survivors of high-level radiation exposure (both human and laboratory animals) have indicated that there are three health effects that should be examined at low levels of exposure: induction of cancer, birth abnormalities (from irradiation in utero), and genetic effects. No other long-term effects of low-level exposure have been conclusively demonstrated in animals or humans

  15. Tracking electric field exposure levels through radio frequency dosimetry

    International Nuclear Information System (INIS)

    Ewing, P.D.; Moore, M.R.; Rochelle, R.W.; Thomas, R.S.; Hess, R.A.; Hoffheins, B.S.

    1991-01-01

    The radio-frequency (rf) dosimeter developed by the Oak Ridge National Laboratory is a portable, pocket-sized cumulative-dose recording device designed to detect and record the strengths and durations of electric fields present in the work areas of naval vessels. The device measures an integrated dose and records the electric fields that exceed the permissible levels set by the American National Standards Institute. Features of the rf dosimeter include a frequency range of 30 MHz to 10 GHz and a three-dimensional sensor. Data obtained with the rf dosimeter will be used to determine the ambient field-strength profile for shipboard personnel over an extended time. Readings are acquired and averaged over a 6-min period corresponding to the rise time of the core body temperature. These values are stored for up to 6 months, after which the data are transferred to a computer via the dosimeter's serial port. The rf dosimeter should increase knowledge of the levels of electric fields to which individuals are exposed. 5 refs., 4 figs

  16. Regulatory control of low level radiation exposure in Tanzania

    International Nuclear Information System (INIS)

    Nyanda, A.M.; Muhogora, W.E.

    1997-01-01

    In Tanzania, the radiation protection law was issued in 1983. Under this law, the National Radiation Commission is responsible for safe uses of ionizing radiation. The regulatory control of the resulting doses from the uses of radiation sources in medicine, industry, research and teaching is presented. The system of control reflects the existing interactions between the National Radiation Commission and users through the established radiation protection infrastructure. From the national dose registry data, it is found that the highest annual individual doses over 10 years ago, came from less than 5% of total monitored workers and were in the range 10 - 15 mSv y -1 . The experienced radiation levels in uncontrolled areas of potential workplaces is less than 1 μSv h -1 . The possibility for associating such low dose levels to the effectiveness of the existing regulatory dose control framework is discussed. Despite of this achievement, the need to improve further the radiation protection and safety programs is found necessary. (author)

  17. Unsound Sound

    DEFF Research Database (Denmark)

    Knakkergaard, Martin

    2016-01-01

    This article discusses the change in premise that digitally produced sound brings about and how digital technologies more generally have changed our relationship to the musical artifact, not simply in degree but in kind. It demonstrates how our acoustical conceptions are thoroughly challenged...... by the digital production of sound and, by questioning the ontological basis for digital sound, turns our understanding of the core term substance upside down....

  18. Equivalent threshold sound pressure levels (ETSPL) for Sennheiser HDA 280 supra-aural audiometric earphones in the frequency range 125 Hz to 8000 Hz.

    Science.gov (United States)

    Poulsen, Torben; Oakley, Sebastian

    2009-05-01

    Hearing threshold sound pressure levels were measured for the Sennheiser HDA 280 audiometric earphone. Hearing thresholds were measured for 25 normal-hearing test subjects at the 11 audiometric test frequencies from 125 Hz to 8000 Hz. Sennheiser HDA 280 is a supra-aural earphone that may be seen as a substitute for the classical Telephonics TDH 39. The results are given as the equivalent threshold sound pressure level (ETSPL) measured in an acoustic coupler specified in IEC 60318-3. The results are in good agreement with an independent investigation from PTB, Braunschweig, Germany. From acoustic laboratory measurements ETSPL values are calculated for the ear simulator specified in IEC 60318-1. Fitting of earphone and coupler is discussed. The data may be used for a future update of the RETSPL standard for supra-aural audiometric earphones, ISO 389-1.

  19. Sound Absorbers

    Science.gov (United States)

    Fuchs, H. V.; Möser, M.

    Sound absorption indicates the transformation of sound energy into heat. It is, for instance, employed to design the acoustics in rooms. The noise emitted by machinery and plants shall be reduced before arriving at a workplace; auditoria such as lecture rooms or concert halls require a certain reverberation time. Such design goals are realised by installing absorbing components at the walls with well-defined absorption characteristics, which are adjusted for corresponding demands. Sound absorbers also play an important role in acoustic capsules, ducts and screens to avoid sound immission from noise intensive environments into the neighbourhood.

  20. Hexachlorobenzene sources, levels and human exposure in the environment of China

    NARCIS (Netherlands)

    Wang, G.; Lu, Y.L.; Han, Jingyi; Luo, W.; Shi, Y.J.; Wang, T.Y.; Sun, Y.M.

    2010-01-01

    This article summarizes the published scientific data on sources, levels and human exposure of hexachlorobenzene (HCB) in China. Potential sources of unintended HCB emission were assessed by production information, emission factors and environmental policies. HCB was observed in various

  1. Metabonomics of Pig Blood Plasma Following Whole Body Exposure to Low Levels of Gb Vapor

    National Research Council Canada - National Science Library

    Bevilacqua, Vicky L; D'Onofrio, Terreiice G; Jakubowski, K. M; Hulet, Stanley W; Maguire, Kelly J; Edwards, Jennifer L; Laramee, James A; Brickhouse, Mark D

    2005-01-01

    ...), for which complex data must be analyzed. Therefore, we have begun an exploration of the use of chemometrics for the correlation of metabolic change with low-level CWA exposure in animal models...

  2. CHEMICAL WEAPONS: DoD Does Not Have a Strategy to Address Low-Level Exposures

    National Research Council Canada - National Science Library

    1998-01-01

    The possible exposure of U.S. troops to low levels of chemical warfare agents in Iraq in the weeks after the Gulf War ceasefire, along with chemical warfare prophylaxis, vaccines, oil well fire emissions, and other battlefield...

  3. Low-level exposure to organophosphate pesticides leads to restrictive lung dysfunction.

    Science.gov (United States)

    Peiris-John, Roshini Janet; Ruberu, Dawala Kusuma; Wickremasinghe, Ananda Rajitha; van-der-Hoek, Wim

    2005-10-01

    Apart from symptomology, there are very few reports on lung function following exposure to low levels of organophosphate (OP) pesticides in man. Twenty-five occupationally exposed farmers and 22 environmentally exposed freshwater fishermen were evaluated between and during OP spray seasons. Forty marine fishermen living away from agricultural areas were recruited as a control group. Forced vital capacity (FVC) and forced expiratory volume in the first second (FEV(1)) were measured by spirometry. Haemoglobin corrected erythrocyte acetylcholinesterase (AChE) levels were measured during and between (baseline estimation) spray seasons using a portable WHO-approved Test-mate system (EQM Research, Ohio). FVC ratio was lower in the farmers as compared to the controls (P<0.001) between exposure seasons. In the farmers, FVC ratio decreased further during the exposure season (P=0.023). FEV(1) was lower in the farmers as compared to the controls in both periods (P<0.05). In the fishermen, the decrease in ratios of FVC and FEV(1) following exposure to pesticides was not significant. FEV(1)/FVC ratios were similar in the three groups between (P=0.988) and during (P=0.159) exposure periods. Following exposure to OPs, AChE levels dropped 12.75% in the farmers (P<0.001) and 5.62% in the freshwater fishermen (P=0.001). Occupational exposure to OP results in restrictive lung dysfunction, a phenomenon not observed following environmental exposure.

  4. Why orchestral musicians are bound to wear earplugs: About the ineffectiveness of physical measures to reduce sound exposure

    NARCIS (Netherlands)

    Wenmaekers, R.H.C.; Nicolai, B.; Hornikx, M.C.J.; Kohlrausch, A.G.

    2017-01-01

    Symphony orchestra musicians are exposed to noise levels that put them at risk of developing hearing damage. This study evaluates the potential effectivity of common control measures used in orchestras on open stages with a typical symphonic setup. A validated acoustic prediction model is used that

  5. Is beryllium-induced lung cancer caused only by soluble forms and high exposure levels?

    Science.gov (United States)

    Schubauer-Berigan, Mary K; Couch, James R; Deddens, James A

    2017-08-01

    The US Occupational Safety and Health Administration (OSHA) recently proposed a permissible exposure limit of 0.2 µg/m 3 for beryllium, based partly on extrapolated estimates of lung cancer risk from a pooled occupational cohort. The purpose of the present analysis was to evaluate whether cohort members exposed at lower levels to mainly insoluble forms of beryllium exhibit increased risk of lung cancer. We conducted Cox proportional hazards regression analyses among 75 lung cancer cases in age-based risk sets within two lower exposure plants in the pooled cohort followed from 1940 to 2005. We used categorical and power models to evaluate exposure-response patterns for mean and cumulative beryllium exposures in the two-plant cohort, comparing findings with the full pooled cohort. We also evaluated the distribution of exposure-years in each cohort by solubility class (soluble, insoluble and mixed). 98% of workers in the two-plant cohort were hired between 1955 and 1969. The mean beryllium exposure averaged 1.3 µg/m 3 and the predominant form was insoluble. Adjusting for confounders, we observed a monotonic increase in lung cancer mortality across exposure categories in the two-plant cohort. The exposure-response coefficients (per unit ln exposure) were 0.270 (p=0.061) for mean exposure and 0.170 (p=0.033) for cumulative exposure, compared with 0.155 and 0.094 (respectively) in the full cohort. The low-exposure levels at these two plants and the predominance of insoluble beryllium suggest that the overall pooled cohort findings on which OSHA's lung cancer risk assessment is based are relevant for current workers exposed to any form of beryllium. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. Sound classification of dwellings

    DEFF Research Database (Denmark)

    Rasmussen, Birgit

    2012-01-01

    National schemes for sound classification of dwellings exist in more than ten countries in Europe, typically published as national standards. The schemes define quality classes reflecting different levels of acoustical comfort. Main criteria concern airborne and impact sound insulation between...... dwellings, facade sound insulation and installation noise. The schemes have been developed, implemented and revised gradually since the early 1990s. However, due to lack of coordination between countries, there are significant discrepancies, and new standards and revisions continue to increase the diversity...... is needed, and a European COST Action TU0901 "Integrating and Harmonizing Sound Insulation Aspects in Sustainable Urban Housing Constructions", has been established and runs 2009-2013, one of the main objectives being to prepare a proposal for a European sound classification scheme with a number of quality...

  7. HELLE: Health Effects of Low Level Exposures/ Gezondheidseffecten van lage blootstellingniveaus [International workshop: Influence of low level exposures to chemicals and radiation on human and ecological health

    Energy Technology Data Exchange (ETDEWEB)

    Schoten, Eert

    1998-11-26

    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

  8. Sound generator

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2008-01-01

    A sound generator, particularly a loudspeaker, configured to emit sound, comprising a rigid element (2) enclosing a plurality of air compartments (3), wherein the rigid element (2) has a back side (B) comprising apertures (4), and a front side (F) that is closed, wherein the generator is provided

  9. Sound generator

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2010-01-01

    A sound generator, particularly a loudspeaker, configured to emit sound, comprising a rigid element (2) enclosing a plurality of air compartments (3), wherein the rigid element (2) has a back side (B) comprising apertures (4), and a front side (F) that is closed, wherein the generator is provided

  10. Sound generator

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2007-01-01

    A sound generator, particularly a loudspeaker, configured to emit sound, comprising a rigid element (2) enclosing a plurality of air compartments (3), wherein the rigid element (2) has a back side (B) comprising apertures (4), and a front side (F) that is closed, wherein the generator is provided

  11. Long-term exposure to low-level arsenic in drinking water and diabetes incidence

    DEFF Research Database (Denmark)

    Bräuner, Elvira Vaclavik; Nordsborg, Rikke Baastrup; Andersen, Zorana Jovanovic

    2014-01-01

    BACKGROUND: Established causes of diabetes do not fully explain the present epidemic. High-level arsenic exposure has been implicated in diabetes risk, but the effect of low-level arsenic exposure in drinking water remains unclear. OBJECTIVE: We sought to determine whether long-term exposure to low......-level arsenic in drinking water in Denmark is associated with an increased risk of diabetes using a large prospective cohort. METHODS: During 1993-1997, we recruited 57,053 persons. We followed each cohort member for diabetes occurrence from enrollment until 31 December 2006. We traced and geocoded residential...... exposure and diabetes incidence, separately for two definitions of diabetes: all cases and a more strict definition in which cases of diabetes based solely on blood glucose results were excluded. RESULTS: Over a mean follow-up period of 9.7 years for 52,931 eligible participants, there were a total of 4...

  12. Survey of RF exposure levels from mobile telephone base stations in Australia.

    Science.gov (United States)

    Henderson, S I; Bangay, M J

    2006-01-01

    This paper reports the results of an exposure level survey of radiofrequency electromagnetic energy originating from mobile telephone base station antennas. Measurements of CDMA800, GSM900, GSM1800, and 3G(UMTS) signals were performed at distances ranging over 50 to 500 m from 60 base stations in five Australian cities. The exposure levels from these mobile telecommunications base stations were found to be well below the general public exposure limits of the ICNIRP guidelines and the Australian radiofrequency standard (ARPANSA RPS3). The highest recorded level from a single base station was 7.8 x 10(-3) W/m(2), which translates to 0.2% of the general public exposure limit.

  13. Constraints on decay of environmental sound memory in adult rats.

    Science.gov (United States)

    Sakai, Masashi

    2006-11-27

    When adult rats are pretreated with a 48-h-long 'repetitive nonreinforced sound exposure', performance in two-sound discriminative operant conditioning transiently improves. We have already proven that this 'sound exposure-enhanced discrimination' is dependent upon enhancement of the perceptual capacity of the auditory cortex. This study investigated principles governing decay of sound exposure-enhanced discrimination decay. Sound exposure-enhanced discrimination disappeared within approximately 72 h if animals were deprived of environmental sounds after sound exposure, and that shortened to less than approximately 60 h if they were exposed to environmental sounds in the animal room. Sound-deprivation itself exerted no clear effects. These findings suggest that the memory of a passively exposed behaviorally irrelevant sound signal does not merely pass along the intrinsic lifetime but also gets deteriorated by other incoming signals.

  14. Modification of otoacoustic emissions following ear-level exposure to MP3 player music.

    Science.gov (United States)

    Bhagat, Shaum P; Davis, Anne M

    2008-12-01

    The purpose of this study was to examine if a pre-determined exposure level and duration of MP3 player music would result in significant changes in cochlear function when measured with audiometric and physiological methods. Distortion-product otoacoustic emissions (DPOAEs), synchronized spontaneous otoacoustic emissions (SSOAEs), and hearing thresholds were measured in 20 normal-hearing adults before and after a 30-minute MP3 player music exposure. DPOAEs were acquired with 65/45 dB SPL primary tones (f(2)=0.842-7.996 kHz) with a frequency resolution of 8 points/octave. A probe microphone system recorded ear-canal music levels and was used to equalize levels at approximately 85 dBC across individuals during the music presentation. Comparison of pre- and post-exposure measurements revealed no significant differences in hearing thresholds, but DPOAE levels in half-octave bands centered from 1.4-6.0 kHz were significantly reduced following the music exposure. Post-exposure shifts in SSOAE frequency and level were highly variable in individuals identified with SSOAEs. The results for the exposure conditions explored in this study indicate that changes in otoacoustic emissions may precede the development of music-induced hearing threshold shifts.

  15. Acute myeloid and chronic lymphoid leukaemias and exposure to low-level benzene among petroleum workers

    Science.gov (United States)

    Rushton, L; Schnatter, A R; Tang, G; Glass, D C

    2014-01-01

    Background: High benzene exposure causes acute myeloid leukaemia (AML). Three petroleum case–control studies identified 60 cases (241 matched controls) for AML and 80 cases (345 matched controls) for chronic lymphoid leukaemia (CLL). Methods: Cases were classified and scored regarding uncertainty by two haematologists using available diagnostic information. Blinded quantitative benzene exposure assessment used work histories and exposure measurements adjusted for era-specific circumstances. Statistical analyses included conditional logistic regression and penalised smoothing splines. Results: Benzene exposures were much lower than previous studies. Categorical analyses showed increased ORs for AML with several exposure metrics, although patterns were unclear; neither continuous exposure metrics nor spline analyses gave increased risks. ORs were highest in terminal workers, particularly for Tanker Drivers. No relationship was found between benzene exposure and risk of CLL, although the Australian study showed increased risks in refinery workers. Conclusion: Overall, this study does not persuasively demonstrate a risk between benzene and AML. A previously reported strong relationship between myelodysplastic syndrome (MDS) (potentially previously reported as AML) at our study's low benzene levels suggests that MDS may be the more relevant health risk for lower exposure. Higher CLL risks in refinery workers may be due to more diverse exposures than benzene alone. PMID:24357793

  16. Airborne exposure and soil levels associated with lead abatement of a steel tank.

    Science.gov (United States)

    Lange, John H

    2002-02-01

    This study reports on airborne exposure levels and soil concentrations of lead in regard to abatement of a steel structure (water tank). The tank was de-leaded by abrasive sand blasting. The ball of the tank had a lead surface level that exceeded the Environmental Protection Agency (EPA) definition of lead-based paint (LBP) (0.5% lead), but paint on stem and base was below this criterion. Personal and area airborne samples were collected during different activities of lead abatement of the tank. Summary results suggest during abrasive blasting of ball and stem/base personal exposure levels, as reported with arithmetic and geometric means, exceed the Occupational Safety and Health Administration (OSHA) permissible exposure limit (50 microg/m3). Highest personal exposure (occupational exposure) was associated with blasting of ball. Distribution of airborne and soil samples suggest non-normality and is best represented by a logarithmic form. Geometric standard deviations for air and soil lead support a non-normal distribution. Outlying values were found for personal and area air samples. Exposure levels associated with blasting stem/base section of tank support OSHA's policy requiring air monitoring of work at levels below the criterion established by EPA in identifying LBP. Area samples were statistically lower than personal samples associated with blasting ball and stem/base of tank. Exposure data suggest that workers performing abatement on steel structures have elevated lead exposure from surface lead. Respirator protection requirements are discussed. Soil lead concentration was suggested to decrease as distance increased from tank. Soil lead is suggested to be a result of deposition from LBP on tank surface. Minimal efforts were required to reduce average lead soil levels below EPA's upper acceptable criterion (1200 ppm Pb).

  17. The Impact of Different Permissible Exposure Limits on Hearing Threshold Levels Beyond 25 dBA.

    Science.gov (United States)

    Sayapathi, Balachandar S; Su, Anselm Ting; Koh, David

    2014-10-01

    Development of noise-induced hearing loss is reliant on a few factors such as frequency, intensity, and duration of noise exposure. The occurrence of this occupational malady has doubled from 120 million to 250 million in a decade. Countries such as Malaysia, India, and the US have adopted 90 dBA as the permissible exposure limit. According to the US Occupational Safety and Health Administration (OSHA), the exposure limit for noise is 90 dBA, while that of the US National Institute of Occupational Safety and Health (NIOSH) is 85 dBA for 8 hours of noise exposure. This study aimed to assess the development of hearing threshold levels beyond 25 dBA on adoption of 85 dBA as the permissible exposure limit compared to 90 dBA. This is an intervention study done on two automobile factories. There were 203 employees exposed to noise levels beyond the action level. Hearing protection devices were distributed to reduce noise levels to a level between the permissible exposure limit and action level. The permissible exposure limits were 90 and 85 dBA in factories 1 and 2, respectively, while the action levels were 85 and 80 dBA, respectively. The hearing threshold levels of participants were measured at baseline and at first month of postshift exposure of noise. The outcome was measured by a manual audiometer. McNemar and chi-square tests were used in the statistical analysis. We found that hearing threshold levels of more than 25 dBA has changed significantly from pre-intervention to post-intervention among participants from both factories (3000 Hz for the right ear and 2000 Hz for the left ear). There was a statistically significant association between participants at 3000 Hz on the right ear at 'deteriorated' level ( χ² (1) = 4.08, φ = - 0.142, P = 0.043), whereas there was worsening of hearing threshold beyond 25 dBA among those embraced 90 dBA. The adoption of 85 dBA as the permissible exposure limit has preserved hearing threshold level among participants at 3000 Hz

  18. Operator dependency of the radiation exposure in cardiac interventions: feasibility of ultra low dose levels

    International Nuclear Information System (INIS)

    Emre Ozpelit, Mehmet; Ercan, Ertugrul; Pekel, Nihat; Tengiz, Istemihan; Yilmaz, Akar; Ozpelit, Ebru; Ozyurtlu, Ferhat

    2017-01-01

    Introduction: Mean radiation exposure in invasive cardiology varies greatly between different centres and interventionists. The International Commission on Radiological Protection and the EURATOM Council stipulate that, despite reference values, 'All medical exposure for radiodiagnostic purposes shall be kept as low as reasonably achievable' (ALARA). The purpose of this study is to establish the effects of the routine application of ALARA principles and to determine operator and procedure impact on radiation exposure in interventional cardiology. Materials and methods: A total of 240 consecutive cardiac interventional procedures were analysed. Five operators performed the procedures, two of whom were working in accordance with ALARA principles (Group 1 operators) with the remaining three working in a standard manner (Group 2 operators). Radiation exposure levels of these two groups were compared. Results: Total fluoroscopy time and the number of radiographic runs were similar between groups. However, dose area product and cumulative dose were significantly lower in Group 1 when compared with Group 2. Radiation levels of Group 1 were far below even the reference levels in the literature, thus representing an ultra-low-dose radiation exposure in interventional cardiology. Conclusion: By use of simple radiation reducing techniques, ultra-low-dose radiation exposure is feasible in interventional cardiology. Achievability of such levels depends greatly on operator awareness, desire, knowledge and experience of radiation protection. (authors)

  19. Effect of Short-term 900 MHz low level electromagnetic radiation exposure on blood serotonin and glutamate levels.

    Science.gov (United States)

    Eris, A H; Kiziltan, H S; Meral, I; Genc, H; Trabzon, M; Seyithanoglu, H; Yagci, B; Uysal, O

    2015-01-01

    Long term exposure to low level electromagnetic radiation (LLER) by using cellular phones causes serious health problems. Ten male Wistar Albino rats were anesthetized 30 min before the LLER exposure, 0.5 ml blood was taken from the tail vein of rats in order to determine control values. Rats were grouped by three and placed on a plexi-glass flat. A fixed equivalent frequency emitter device was used. A sign to be an electromagnetic field 15.14 V/m (608 mW/m(2)) in strength in the head region with 100 kHz FM modulation at 900 MHz was applied to the animals. After calculating the ideal position for the device, electromagnetic LLER energy was applied for 45 minutes from a distance to be equal with energy transmitted by a mobile phone from a 0.5-1 cm distance to their head regions. After 1.5 hours and before the rats awoke, 0.5 ml of blood was taken from the tail veins in order to determine the treatment values. Plasma 5-HT and glutamate levels were measured by enzyme immunoassay (EIA) using commercial kits. It was found that a single 45 min of LLER exposure increased the blood 5-HT level significantly, but did not change the glutamate level of rats. It was concluded that even a single 45 min of LLER exposure may produce an increase in 5-HT level without changing the blood glutamate level. Increased 5-HT level may lead to a retarded learning and a deficit in spatial memory (Tab. 2, Fig. 2, Ref. 24).

  20. Using mineralogy and higher-level taxonomy as indicators of species sensitivity to pH: A case-study of Puget Sound

    Directory of Open Access Journals (Sweden)

    Shallin Busch

    2017-09-01

    Full Text Available Information on ecosystem sensitivity to global change can help guide management decisions. Here, we characterize the sensitivity of the Puget Sound ecosystem to ocean acidification by estimating, at a number of taxonomic levels, the direct sensitivity of its species. We compare sensitivity estimates based on species mineralogy and on published literature from laboratory experiments and field studies. We generated information on the former by building a database of species in Puget Sound with mineralogy estimates for all CaCO3-forming species. For the latter, we relied on a recently developed database and meta-analysis on temperate species responses to increased CO2. In general, species sensitivity estimates based on the published literature suggest that calcifying species are more sensitive to increased CO2 than non-calcifying species. However, this generalization is incomplete, as non-calcifying species also show direct sensitivity to high CO2 conditions. We did not find a strong link between mineral solubility and the sensitivity of species survival to changes in carbonate chemistry, suggesting that, at coarse scales, mineralogy plays a lesser role to other physiological sensitivities. Summarizing species sensitivity at the family level resulted in higher sensitivity scalar scores than at the class level, suggesting that grouping results at the class level may overestimate species sensitivity. This result raises caution about the use of broad generalizations on species response to ocean acidification, particularly when developing summary information for specific locations. While we have much to learn about species response to ocean acidification and how to generalize ecosystem response, this study on Puget Sound suggests that detailed information on species performance under elevated carbon dioxide conditions, summarized at the lowest taxonomic level possible, is more valuable than information on species mineralogy.

  1. Does apartment's distance to an in-built transformer room predict magnetic field exposure levels?

    Science.gov (United States)

    Huss, Anke; Goris, Kelly; Vermeulen, Roel; Kromhout, Hans

    2013-01-01

    It has been shown that magnetic field exposure in apartments located directly on top or adjacent to transformer rooms is higher compared with exposure in apartments located further away from the transformer rooms. It is unclear whether this also translates into exposure contrast among individuals living in these apartments. We performed spot measurements of magnetic fields in 35 apartments in 14 apartment buildings with an in-built transformer and additionally performed 24-h personal measurements in a subsample of 24 individuals. Apartments placed directly on top of or adjacent to a transformer room had on average exposures of 0.42 μT, apartments on the second floor on top of a transformer room, or sharing a corner or edge with the transformer room had 0.11 μT, and apartments located further away from the transformer room had levels of 0.06 μT. Personal exposure levels were approximately a factor 2 lower compared with apartment averages, but still showed exposure contrasts, but only for those individuals who live in the apartments directly on top or adjacent to a transformer room compared with those living further away, with 0.23 versus 0.06 μT for personal exposure when indoors, respectively. A classification of individuals into 'high' and 'low' exposed based on the location of their apartment within a building with an in-built transformer is possible and could be applied in future epidemiological studies.

  2. [Myocardial ultrastructural changes in rats following different levels of acute +Gz exposure].

    Science.gov (United States)

    Zheng, Jun; Liu, Cheng-gang; Ren, Li; Xiao, Xiao-guang; Xu, Shu-xuan; Wang, Ping; Ji, Gui-ying

    2004-06-01

    To observe the effects of different levels of acute +Gz exposure on myocardial ultrastructure of rats and provide experimental basis for further development of anti-G measures. Twenty male Wistar rats were randomly divided into 4 groups (n=5): normal control group, +20 Gz group, +10 Gz group and +5 Gz group. Profile of the centrifuge +Gz exposure was trapezoidal, in which +20 Gz lasted for 30 s, +10 Gz for 1.5 min. +5 Gz exposure was repeated for 3 times with 30 min interval and each for 1.5 min. Myocardial tissue of left ventricle was sampled for transmission electron microscopy 5 h after exposure. +20 Gz and +10 Gz exposure caused obvious edema of myocardial and endothelial cells, myofibril disorder and injuries of mitochondria and nucleus. Breaks of myocardial fiber, formation of contraction bands and rupture of mitochondria were also observed in +20 Gz group. In +5 Gz group, there was still slight edema of myocardial and endothelial cells, while organic changes of myocardial ultrastructure were not observed. High +Gz exposure can cause myocardial ultrastructural injury in rats. Slight reversible injured response can also be observed in myocardial cell after repeated moderate level of +Gz exposure. This indicates that attention should be paid to the study of the effect of high +Gz on heart in pilots.

  3. Sound Zones

    DEFF Research Database (Denmark)

    Møller, Martin Bo; Olsen, Martin

    2017-01-01

    Sound zones, i.e. spatially confined regions of individual audio content, can be created by appropriate filtering of the desired audio signals reproduced by an array of loudspeakers. The challenge of designing filters for sound zones is twofold: First, the filtered responses should generate...... an acoustic separation between the control regions. Secondly, the pre- and post-ringing as well as spectral deterioration introduced by the filters should be minimized. The tradeoff between acoustic separation and filter ringing is the focus of this paper. A weighted L2-norm penalty is introduced in the sound...

  4. Low-level maternal methylmercury exposure through rice ingestion and potential implications for offspring health

    Energy Technology Data Exchange (ETDEWEB)

    Rothenberg, Sarah E., E-mail: rothenberg.sarah@gmail.com [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China); Feng Xinbin, E-mail: fengxinbin@vip.skleg.cn [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China); Li Ping [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China)

    2011-04-15

    Fish consumption is considered the primary pathway for MeHg (MeHg) exposure; however, MeHg exposure also occurs through rice ingestion. Rice is grown in an aquatic environment and although documented MeHg concentrations in rice are lower compared to fish tissue, human exposures exceed international guidelines in some regions where rice is a staple food and rice MeHg levels are elevated. Studies concerning human health exposure to MeHg should also include populations where maternal MeHg exposure occurs through ingestion of rice. Rice does not contain long-chain polyunsaturated fatty acids, which are associated with confounding developmental outcomes in offspring. Rice is also a staple food for more than half the world's population; therefore, it is critical to investigate the potential health risks of maternal ingestion of rice to the developing fetus, the most susceptible population to the deleterious effects of MeHg. Data concerning MeHg in rice are reviewed and micronutrients in rice are discussed. - Research highlights: > Maternal methylmercury exposure through rice may be important. > Rice does not contain the same micronutrients as fish, but may contain methylmercury. > Effects to offspring from methylmercury without beneficial micronutrients are unknown. - Studies concerning maternal methylmercury exposure and cognitive outcomes for offspring should include populations where rice ingestion is the primary methylmercury exposure pathway.

  5. Low-level maternal methylmercury exposure through rice ingestion and potential implications for offspring health

    International Nuclear Information System (INIS)

    Rothenberg, Sarah E.; Feng Xinbin; Li Ping

    2011-01-01

    Fish consumption is considered the primary pathway for MeHg (MeHg) exposure; however, MeHg exposure also occurs through rice ingestion. Rice is grown in an aquatic environment and although documented MeHg concentrations in rice are lower compared to fish tissue, human exposures exceed international guidelines in some regions where rice is a staple food and rice MeHg levels are elevated. Studies concerning human health exposure to MeHg should also include populations where maternal MeHg exposure occurs through ingestion of rice. Rice does not contain long-chain polyunsaturated fatty acids, which are associated with confounding developmental outcomes in offspring. Rice is also a staple food for more than half the world's population; therefore, it is critical to investigate the potential health risks of maternal ingestion of rice to the developing fetus, the most susceptible population to the deleterious effects of MeHg. Data concerning MeHg in rice are reviewed and micronutrients in rice are discussed. - Research highlights: → Maternal methylmercury exposure through rice may be important. → Rice does not contain the same micronutrients as fish, but may contain methylmercury. → Effects to offspring from methylmercury without beneficial micronutrients are unknown. - Studies concerning maternal methylmercury exposure and cognitive outcomes for offspring should include populations where rice ingestion is the primary methylmercury exposure pathway.

  6. Consumer product exposures associated with urinary phthalate levels in pregnant women

    OpenAIRE

    Buckley, Jessie P.; Palmieri, Rachel T.; Matuszewski, Jeanine M.; Herring, Amy H.; Baird, Donna D.; Hartmann, Katherine E.; Hoppin, Jane A.

    2012-01-01

    Human phthalate exposure is ubiquitous, but little is known regarding predictors of urinary phthalate levels. To explore this, 50 pregnant women aged 18–38 years completed two questionnaires on potential phthalate exposures and provided a first morning void. Urine samples were analyzed for 12 phthalate metabolites. Associations with questionnaire items were evaluated via Wilcoxon tests and t-tests, and r-squared values were calculated in multiple linear regression models. Few measured factors...

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

    International Nuclear Information System (INIS)

    Kang, Kyoung Ah; Lee, Hyung Chul; Lee, Je-Jung

    2014-01-01

    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 H 2 O 2 or menadione was also performed. The experimental exposure groups were incubator control, sham-exposed, combined RF radiation-exposed with or without either H 2 O 2 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 H 2 O 2 or menadione, intracellular ROS levels showed no statically significant alteration compared with exposure to menadione or H 2 O 2 alone. These findings indicate that neither combined RF radiation alone nor combined RF radiation with menadione or H 2 O 2 influences the intracellular ROS level in neuronal cells such as U87, PC12 or SH-SY5Y. (author)

  8. More than 100 Years of Background-Level Sedimentary Metals, Nisqually River Delta, South Puget Sound, Washington

    Science.gov (United States)

    Takesue, Renee K.; Swarzenski, Peter W.

    2011-01-01

    The Nisqually River Delta is located about 25 km south of the Tacoma Narrows in the southern reach of Puget Sound. Delta evolution is controlled by sedimentation from the Nisqually River and erosion by strong tidal currents that may reach 0.95 m/s in the Nisqually Reach. The Nisqually River flows 116 km from the Cascade Range, including the slopes of Mount Rainier, through glacially carved valleys to Puget Sound. Extensive tidal flats on the delta consist of late-Holocene silty and sandy strata from normal river streamflow and seasonal floods and possibly from distal sediment-rich debris flows associated with volcanic and seismic events. In the early 1900s, dikes and levees were constructed around Nisqually Delta salt marshes, and the reclaimed land was used for agriculture and pasture. In 1974, U.S. Fish and Wildlife Service established the Nisqually National Wildlife Refuge on the reclaimed land to protect migratory birds; its creation has prevented further human alteration of the Delta and estuary. In October 2009, original dikes and levees were removed to restore tidal exchange to almost 3 km2 of man-made freshwater marsh on the Nisqually Delta.

  9. Low Level Exposure to GB Vapor in Air: Diagnosis/Dosimetry, Lowest Observable Effect Levels, Performance-Incapacitation, and Possible Delayed Effects

    National Research Council Canada - National Science Library

    1998-01-01

    ...: (I) A glass exposure chamber for whole-body exposure of unanesthetized guinea pigs and marmosets to low levels of OB vapor in air has been designed and constructed, and is in the implementation stage...

  10. Sound intensity

    DEFF Research Database (Denmark)

    Crocker, Malcolm J.; Jacobsen, Finn

    1998-01-01

    This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique.......This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique....

  11. Sound Intensity

    DEFF Research Database (Denmark)

    Crocker, M.J.; Jacobsen, Finn

    1997-01-01

    This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique.......This chapter is an overview, intended for readers with no special knowledge about this particular topic. The chapter deals with all aspects of sound intensity and its measurement from the fundamental theoretical background to practical applications of the measurement technique....

  12. Acute Exposure to Low-to-Moderate Carbon Dioxide Levels and Submariner Decision Making.

    Science.gov (United States)

    Rodeheffer, Christopher D; Chabal, Sarah; Clarke, John M; Fothergill, David M

    2018-06-01

    Submarines routinely operate with higher levels of ambient carbon dioxide (CO2) (i.e., 2000 - 5000 ppm) than what is typically considered normal (i.e., 400 - 600 ppm). Although significant cognitive impairments are rarely reported at these elevated CO2 levels, recent studies using the Strategic Management Simulation (SMS) test have found impairments in decision-making performance during acute CO2 exposure at levels as low as 1000 ppm. This is a potential concern for submarine operations, as personnel regularly make mission-critical decisions that affect the safety and efficiency of the vessel and its crew while exposed to similar levels of CO2. The objective of this study was to determine if submariner decision-making performance is impacted by acute exposure to levels of CO2 routinely present in the submarine atmosphere during sea patrols. Using a subject-blinded balanced design, 36 submarine-qualified sailors were randomly assigned to receive 1 of 3 CO2 exposure conditions (600, 2500, or 15,000 ppm). After a 45-min atmospheric acclimation period, participants completed an 80-min computer-administered SMS test as a measure of decision making. There were no significant differences for any of the nine SMS measures of decision making between the CO2 exposure conditions. In contrast to recent research demonstrating cognitive deficits on the SMS test in students and professional-grade office workers, we were unable to replicate this effect in a submariner population-even with acute CO2 exposures more than an order of magnitude greater than those used in previous studies that demonstrated such effects.Rodeheffer CD, Chabal S, Clarke JM, Fothergill DM. Acute exposure to low-to-moderate carbon dioxide levels and submariner decision making. Aerosp Med Hum Perform. 2018; 89(6):520-525.

  13. A hybrid modeling with data assimilation to evaluate human exposure level

    Science.gov (United States)

    Koo, Y. S.; Cheong, H. K.; Choi, D.; Kim, A. L.; Yun, H. Y.

    2015-12-01

    Exposure models are designed to better represent human contact with PM (Particulate Matter) and other air pollutants such as CO, SO2, O3, and NO2. The exposure concentrations of the air pollutants to human are determined by global and regional long range transport of global and regional scales from Europe and China as well as local emissions from urban and road vehicle sources. To assess the exposure level in detail, the multiple scale influence from background to local sources should be considered. A hybrid air quality modeling methodology combing a grid-based chemical transport model with a local plume dispersion model was used to provide spatially and temporally resolved air quality concentration for human exposure levels in Korea. In the hybrid modeling approach, concentrations from a grid-based chemical transport model and a local plume dispersion model are added to provide contributions from photochemical interactions, long-range (regional) transport and local-scale dispersion. The CAMx (Comprehensive Air quality Model with Extensions was used for the background concentrations from anthropogenic and natural emissions in East Asia including Korea while the road dispersion by vehicle emission was calculated by CALPUFF model. The total exposure level of the pollutants was finally assessed by summing the background and road contributions. In the hybrid modeling, the data assimilation method based on the optimal interpolation was applied to overcome the discrepancies between the model predicted concentrations and observations. The air quality data from the air quality monitoring stations in Korea. The spatial resolution of the hybrid model was 50m for the Seoul Metropolitan Ares. This example clearly demonstrates that the exposure level could be estimated to the fine scale for the exposure assessment by using the hybrid modeling approach with data assimilation.

  14. Experimental evaluation of the exposure level onboard Czech Airlines aircraft - measurements verified the routine method

    International Nuclear Information System (INIS)

    Ploc, O.; Spurny, F.; Turek, K.; Kovar, I.

    2008-01-01

    Air-crew members are exposed to ionizing radiation due to their work on board of air-crafts. The International Commission on Radiological Protection (ICRP) in 1990 recommends that exposure to cosmic radiation in the operation of jet aircraft should be recognised as occupational exposure. Czech air transport operators are therefore obliged to ensure: - Air-crew members to be well informed about the exposure level and health risks; - An analysis of complete exposure level of aircraft crew and its continuing monitoring in cases of exceeding the informative value 1 mSv; - A compliance of limit 1 mSv during pregnancy Since 1998, after receiving a proper accreditation, the Department of Radiation Dosimetry of Nuclear Physics Institute of Czech Academy of Sciences (DRD) is the competent dosimetric service realized requirements of Notice No.307 of the State Office for Nuclear Safety concerning air-crew exposure (paragraphs 87-90). The DRD has developed routine method of personal dosimetry of aircraft crew in 1998 which has been applied after receiving a proper accreditation in the same year. DRD therefore helps Czech airlines a.s. (CSA) with their legislative obligations mentioned above, and in return, once per four years, in terms of business contract, CSA allows scientific measurements performed by DRD onboard its air-crafts with the aim to verify the method of routine individual monitoring of aircraft crew exposure. (authors)

  15. Polychlorinated biphenyl exposure and corticosterone levels in seven polar seabird species

    International Nuclear Information System (INIS)

    Tartu, S.; Angelier, F.; Bustnes, J.O.; Moe, B.; Hanssen, S.A.; Herzke, D.; Gabrielsen, G.W.; Verboven, N.; Verreault, J.; Labadie, P.; Budzinski, H.; Wingfield, J.C.

    2015-01-01

    The role of polychlorinated biphenyls (PCBs) on exposure-related endocrine effects has been poorly investigated in wild birds. This is the case for stress hormones including corticosterone (CORT). Some studies have suggested that environmental exposure to PCBs and altered CORT secretion might be associated. Here we investigated the relationships between blood PCB concentrations and circulating CORT levels in seven free-ranging polar seabird species occupying different trophic positions, and hence covering a wide range of PCB exposure. Blood ∑ 7 PCB concentrations (range: 61–115,632 ng/g lw) were positively associated to baseline or stress-induced CORT levels in three species and negatively associated to stress-induced CORT levels in one species. Global analysis suggests that in males, baseline CORT levels generally increase with increasing blood ∑ 7 PCB concentrations, whereas stress-induced CORT levels decrease when reaching high blood ∑ 7 PCB concentrations. This study suggests that the nature of the PCB-CORT relationships may depend on the level of PCB exposure. - Highlights: • Relationships between PCBs and stress hormones (CORT) are not well known in birds. • We measured blood PCBs, baseline and stress-induced CORT in seven seabird species. • ∑PCB was positively associated to baseline or stress-induced CORT in three species. • ∑PCBs was negatively linked to stress-induced CORT in the most contaminated species. • The nature of the PCB-CORT relationships may depend on the level of PCB exposure. - In polar seabird species, the relationship between PCB and CORT concentrations may be related to the levels of contamination

  16. Cell type-specific suppression of mechanosensitive genes by audible sound stimulation.

    Science.gov (United States)

    Kumeta, Masahiro; Takahashi, Daiji; Takeyasu, Kunio; Yoshimura, Shige H

    2018-01-01

    Audible sound is a ubiquitous environmental factor in nature that transmits oscillatory compressional pressure through the substances. To investigate the property of the sound as a mechanical stimulus for cells, an experimental system was set up using 94.0 dB sound which transmits approximately 10 mPa pressure to the cultured cells. Based on research on mechanotransduction and ultrasound effects on cells, gene responses to the audible sound stimulation were analyzed by varying several sound parameters: frequency, wave form, composition, and exposure time. Real-time quantitative PCR analyses revealed a distinct suppressive effect for several mechanosensitive and ultrasound-sensitive genes that were triggered by sounds. The effect was clearly observed in a wave form- and pressure level-specific manner, rather than the frequency, and persisted for several hours. At least two mechanisms are likely to be involved in this sound response: transcriptional control and RNA degradation. ST2 stromal cells and C2C12 myoblasts exhibited a robust response, whereas NIH3T3 cells were partially and NB2a neuroblastoma cells were completely insensitive, suggesting a cell type-specific response to sound. These findings reveal a cell-level systematic response to audible sound and uncover novel relationships between life and sound.

  17. Local Mechanisms for Loud Sound-Enhanced Aminoglycoside Entry into Outer Hair Cells

    Directory of Open Access Journals (Sweden)

    Hongzhe eLi

    2015-04-01

    Full Text Available Loud sound exposure exacerbates aminoglycoside ototoxicity, increasing the risk of permanent hearing loss and degrading the quality of life in affected individuals. We previously reported that loud sound exposure induces temporary threshold shifts (TTS and enhances uptake of aminoglycosides, like gentamicin, by cochlear outer hair cells (OHCs. Here, we explore mechanisms by which loud sound exposure and TTS could increase aminoglycoside uptake by OHCs that may underlie this form of ototoxic synergy.Mice were exposed to loud sound levels to induce TTS, and received fluorescently-tagged gentamicin (GTTR for 30 minutes prior to fixation. The degree of TTS was assessed by comparing auditory brainstem responses before and after loud sound exposure. The number of tip links, which gate the GTTR-permeant mechanoelectrical transducer (MET channels, was determined in OHC bundles, with or without exposure to loud sound, using scanning electron microscopy.We found wide-band noise (WBN levels that induce TTS also enhance OHC uptake of GTTR compared to OHCs in control cochleae. In cochlear regions with TTS, the increase in OHC uptake of GTTR was significantly greater than in adjacent pillar cells. In control mice, we identified stereociliary tip links at ~50% of potential positions in OHC bundles. However, the number of OHC tip links was significantly reduced in mice that received WBN at levels capable of inducing TTS.These data suggest that GTTR uptake by OHCs during TTS occurs by increased permeation of surviving, mechanically-gated MET channels, and/or non-MET aminoglycoside-permeant channels activated following loud sound exposure. Loss of tip links would hyperpolarize hair cells and potentially increase drug uptake via aminoglycoside-permeant channels expressed by hair cells. The effect of TTS on aminoglycoside-permeant channel kinetics will shed new light on the mechanisms of loud sound-enhanced aminoglycoside uptake, and consequently on ototoxic

  18. Lifetime Exposure to Intimate Partner Violence and Proinflammatory Cytokine Levels Across the Perinatal Period.

    Science.gov (United States)

    Robertson Blackmore, Emma; Mittal, Mona; Cai, Xueya; Moynihan, Jan A; Matthieu, Monica M; O'Connor, Thomas G

    2016-10-01

    Intimate partner violence (IPV) is a public health concern, affecting one-third of US women. Prior research suggests an association between exposure to IPV and poor maternal perinatal health, but the underlying biological correlates are not well understood. This study examined the relationship between exposure to IPV and proinflammatory cytokine levels, a candidate mechanism accounting for poor psychiatric and obstetric outcomes, across the perinatal period. Data were obtained from a prospective, longitudinal cohort study of 171 women receiving obstetrical care from a hospital-based practice serving a predominantly low-income minority population. Participants completed questionnaires on IPV exposure, psychiatric symptoms, and psychosocial and obstetric factors and provided blood samples at 18 and 32 weeks of gestation and 6 weeks and 6 months postpartum. Serum levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were assayed via enzyme-linked immunosorbent assay. Thirty-five (20.5%) women reported lifetime exposure to IPV and 7 (4.1%) reported being physically hurt in the preceding 12 months (4 while pregnant). Lifetime exposure to IPV was associated with increased likelihood of experiencing perinatal depression and smoking during pregnancy. Women with a history of IPV had significantly higher levels of TNF-α at 18 weeks (z = -2.29, p < 0.05), but significantly smaller changes in levels of IL-6 (β = -0.36, p = 0.04) across time. Lifetime exposure to IPV was associated with a range of adverse mental health outcomes and may affect proinflammatory cytokine levels in pregnancy.

  19. Maternal age at Holocaust exposure and maternal PTSD independently influence urinary cortisol levels in adult offspring

    Directory of Open Access Journals (Sweden)

    Heather N Bader

    2014-07-01

    Full Text Available Background: Parental traumatization has been associated with increased risk for the expression of psychopathology in offspring, and maternal PTSD appears to increase the risk for the development of offspring PTSD. In this study, Holocaust-related maternal age of exposure and PTSD were evaluated for their association with offspring ambient cortisol and PTSD-associated symptom expression. Method: 95 Holocaust offspring and Jewish comparison subjects received diagnostic and psychological evaluations, and 24 hour urinary cortisol was assayed by RIA. Offspring completed the Parental PTSD Questionnaire to assess maternal PTSD status. Maternal Holocaust exposure was identified as having occurred in childhood, adolescence or adulthood and examined in relation to offspring psychobiology. Results: Urinary cortisol levels did not differ for Holocaust offspring and comparison subjects but differed significantly in offspring based on maternal age of exposure and maternal PTSD status. Increased maternal age of exposure and maternal PTSD were each associated with lower urinary cortisol in offspring, but did not exhibit a significant interaction. In addition, offspring PTSD-associated symptom severity increased with maternal age at exposure and PTSD diagnosis. A regression analysis of correlates of offspring cortisol indicated that both maternal age of exposure and maternal PTSD were significant predictors of lower offspring urinary cortisol, whereas childhood adversity and offspring PTSD symptoms were not. Conclusions: Offspring low cortisol and PTSD-associated symptom expression are related to maternal age of exposure, with the greatest effects associated with increased age at exposure. These effects are relatively independent of the negative consequences of being raised by a trauma survivor. These observations highlight the importance of maternal age of exposure in determining a psychobiology in offspring that is consistent with increased risk for stress

  20. Maternal Age at Holocaust Exposure and Maternal PTSD Independently Influence Urinary Cortisol Levels in Adult Offspring

    Science.gov (United States)

    Bader, Heather N.; Bierer, Linda M.; Lehrner, Amy; Makotkine, Iouri; Daskalakis, Nikolaos P.; Yehuda, Rachel

    2014-01-01

    Background: Parental traumatization has been associated with increased risk for the expression of psychopathology in offspring, and maternal posttraumatic stress disorder (PTSD) appears to increase the risk for the development of offspring PTSD. In this study, Holocaust-related maternal age of exposure and PTSD were evaluated for their association with offspring ambient cortisol and PTSD-associated symptom expression. Method: Ninety-five Holocaust offspring and Jewish comparison subjects received diagnostic and psychological evaluations, and 24 h urinary cortisol was assayed by RIA. Offspring completed the parental PTSD questionnaire to assess maternal PTSD status. Maternal Holocaust exposure was identified as having occurred in childhood, adolescence, or adulthood and examined in relation to offspring psychobiology. Results: Urinary cortisol levels did not differ for Holocaust offspring and comparison subjects but differed significantly in offspring based on maternal age of exposure and maternal PTSD status. Increased maternal age of exposure and maternal PTSD were each associated with lower urinary cortisol in offspring, but did not exhibit a significant interaction. In addition, offspring PTSD-associated symptom severity increased with maternal age at exposure and PTSD diagnosis. A regression analysis of correlates of offspring cortisol indicated that both maternal age of exposure and maternal PTSD were significant predictors of lower offspring urinary cortisol, whereas childhood adversity and offspring PTSD symptoms were not. Conclusion: Offspring low cortisol and PTSD-associated symptom expression are related to maternal age of exposure, with the greatest effects associated with increased age at exposure. These effects are relatively independent of the negative consequences of being raised by a trauma survivor. These observations highlight the importance of maternal age of exposure in determining a psychobiology in offspring that is consistent with increased

  1. Effects of nocturnal railway noise on sleep fragmentation in young and middle-aged subjects as a function of type of train and sound level.

    Science.gov (United States)

    Saremi, Mahnaz; Grenèche, Jérôme; Bonnefond, Anne; Rohmer, Odile; Eschenlauer, Arnaud; Tassi, Patricia

    2008-12-01

    Due to undisputable effects of noise on sleep structure, especially in terms of sleep fragmentation, the expected development of railway transportation in the next few years might represent a potential risk factor for people living alongside the rail tracks. The aim of this study was to compare the effects of different types of train (freight, automotive, passenger) on arousal from sleep and to determine any differential impact as a function of sound level and age. Twenty young (16 women, 4 men; 25.8 years+/-2.6) and 18 middle-aged (15 women, 3 men; 52.2 years+/-2.5) healthy subjects participated in three whole-night polysomnographic recordings including one control night (35 dBA), and two noisy nights with equivalent noise levels of 40 or 50 dB(A), respectively. Arousal responsiveness increased with sound level. It was the highest in S2 and the lowest in REM sleep. Micro-arousals (3-10 s) occurred at a rate of 25-30%, irrespective of the type of train. Awakenings (>10 s) were produced more frequently by freight train than by automotive and passenger trains. Normal age-related changes in sleep were observed, but they were not aggravated by railway noise, thus questioning whether older persons are less sensitive to noise during sleep. These evidences led to the conclusion that microscopic detection of sleep fragmentation may provide advantageous information on sleep disturbances caused by environmental noises.

  2. Cigarette smoking increases radon working level exposures to all occupants of the smoker's home

    International Nuclear Information System (INIS)

    Johnson, R.H. Jr.; Rosario, A. Jr.

    1990-01-01

    This paper reports that the 1988 National Academy of Sciences report on radon health risks evaluated the combined effects of radon exposures and cigarettes on the lung cancer risk to smokers. This report showed that the risk of lung cancer is about 10 times greater for smokers than for nonsmokers at the same Working Level exposures. In 1986, the Surgeon General reported that 106,000 lung cancer deaths occurred among smokers. Therefore, the health risks of cigarettes alone or in combination with radon exposures are well recognized. What has not been studied is the effect of cigarette smoke on the Working Levels in homes that increases the exposure to radon decay products to all occupants, both smokers and nonsmokers. Preliminary studies in a radon chamber at Radon QC showed that the smoke from a single cigarette increased the Working Levels by a factor of five within four hours. Furthermore, the Working Levels remained at an elevated level for more than 24 hours. The equilibrium ratio of radon decay products to radon gas also went from about 14% up to 71%, with a slow decrease over 24 hours. Similar studies in the homes of a smoker and nonsmoker confirmed the laboratory observations. The studies in homes also showed the effects of thoron decay products

  3. Gestational exposure to high perchlorate concentrations in drinking water and neonatal thyroxine levels.

    Science.gov (United States)

    Amitai, Yona; Winston, Gary; Sack, Joseph; Wasser, Janice; Lewis, Matthew; Blount, Benjamin C; Valentin-Blasini, Liza; Fisher, Nirah; Israeli, Avi; Leventhal, Alex

    2007-09-01

    To assess the effect of gestational perchlorate exposure through drinking water on neonatal thyroxine (T(4)). T(4) values were compared among newborns in Ramat Hasharon, Israel, whose mothers resided in suburbs where drinking water contained perchlorate water exclusively (as determined by a telephone interview) were analyzed as a subset. Serum perchlorate levels in blood from donors residing in the area were used as proxy indicators of exposure. Neonatal T(4) values (mean +/- SD) in the very high, high, and low exposure groups were 13.9 +/- 3.8, 13.9 +/- 3.4, and 14.0 +/- 3.5 microg/dL, respectively (p = NS). Serum perchlorate concentrations in blood from donors residing in areas corresponding to these groups were 5.99 +/- 3.89, 1.19 +/- 1.37, and 0.44 +/- 0.55 microg/L, respectively. T(4) levels of neonates with putative gestational exposure to perchlorate in drinking water were not statistically different from controls. This study finds no change in neonatal T(4) levels despite maternal consumption of drinking water that contains perchlorate at levels in excess of the Environmental Protection Agency (EPA) drinking water equivalent level (24.5 microg/L) based on the National Research Council reference dose (RfD) [0.7 microg/(kg.day)]. Therefore the perchlorate RfD is likely to be protective of thyroid function in neonates of mothers with adequate iodide intake.

  4. Noise exposure under hyperbaric conditions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    Objective evidence exists that divers demonstrate a hearing deficit greater than would be expected from ageing effects alone. Deafness in divers may be caused by a number of factors other than exposure to excessive noise levels, eg barotrauma, ear infection etc. This review concentrates on the concern that exposure of commercial divers to noise while at work may cause a hearing deficit. Sound pressure levels recorded both underwater and in diving chambers often exceed those allowable to workers onshore. However, the sound perceived by the diver is modified both in amplitude and in frequency when he is either underwater or in pressurised chambers. Broadly the effect of this modification is to attenuate the sound and thus offer some protection from high noise levels. The degree of attentuation varies with the frequency of the sound, however it is also possible under specific conditions associated with gas density for the sensitivity to particular frequencies to be amplified above that for normal atmospheric air. The levels of sound observed from some underwater tools are of concern even after allowing for a significant de-sensitisation of the divers` hearing. Reports of tinnitus and temporary hearing loss following a dive are sure signs that the noise levels have been harmful. It is not possible at present to describe risk criteria for hearing damage due to noise exposure associated with diving. (author)

  5. Geluidsexpositie bij gebruik van CEP door F-16 crewchiefs (Sound Exposure Level of F-16 Crew Chiefs Using Communications Earplugs)

    Science.gov (United States)

    2008-03-01

    Communications Earplugs Auteur (s) dr. ir. M.M.J. Houben Programmanummer Projectnummer J.A. Verhave 032.13072 F.W.M. Geurtsen Rubricering rapport Program...de communicatie kiest men voor een geluidniveau dat luider is dan het waargenomen omgevingsgeluid. In theorie kan bet totale geluidsexpositieniveau...Afdelingshoofd Auteur TNO-rapport I TNO-DV 2008 A054 Bijlage A 1 1/3 A Simulatie Simulatie-omgeving Uit een opname gemaakt op Vhiegbasis Volkel hebben

  6. Noise Exposure Estimates of Urban MP3 Player Users

    Science.gov (United States)

    Levey, Sandra; Levey, Tania; Fligor, Brian J.

    2011-01-01

    Purpose: To examine the sound level and duration of use of personal listening devices (PLDs) by 189 college students, ages 18-53 years, as they entered a New York City college campus, to determine whether noise exposure from PLDs was in excess of recommended exposure limits and what factors might influence exposure. Method: Free-field equivalent…

  7. Pesticide Exposure and Cholinesterase Levels in Migrant Farm Workers in Thailand.

    Science.gov (United States)

    Thetkathuek, Anamai; Yenjai, Pornthip; Jaidee, Wanlop; Jaidee, Patchana; Sriprapat, Poonsak

    2017-01-01

    In this study, we examined the effects of pesticides in migrant farm workers from Cambodia after workplace exposure on fruit plantations in eastern Thailand. We studied 891 migrant farm workers employed on pineapple, durian, and rambutan plantations in Thailand. Data were collected via a detailed questionnaire survey and measurements of serum cholinesterase level (SChE). The majority of subjects was male (57.7%), with an average age of 30.3 years. Most subjects (76.8%) were moderately aware of good industrial hygiene practices. SChE level was divided into four groups based on the results. Only 4.4% had normal levels of cholinesterase activity, 20.5% had slightly reduced levels, 58.5% had markedly reduced levels and were "at risk," and 16.6% who had highest levels of cholinesterase inhibition were deemed to be in an "unsafe" range. SChE was classified into two groups, SChE value of 87.5 was "normal" and 39 acres, use a backpack sprayer, or have a low level of compliance with accepted industrial hygiene practices. These three classes of workers are at increased risk of chemical exposures and developing acute or chronic illness from pesticide exposures.

  8. Overnight hypoxic exposure and glucagon-like peptide-1 and leptin levels in humans

    DEFF Research Database (Denmark)

    Snyder, Eric M; Carr, Richard D; Deacon, Carolyn F

    2008-01-01

    increases with hypoxia; however, the influence of hypoxia on GLP-1 has not been studied in animals or humans to date. We sought to determine the influence of normobaric hypoxia on plasma leptin and GLP-1 levels in 25 healthy humans. Subjects ingested a control meal during normoxia and after 17 h of exposure...

  9. 75 FR 14153 - National Advisory Committee for Acute Exposure Guideline Levels for Hazardous Substances; Notice...

    Science.gov (United States)

    2010-03-24

    ..., the various aspects of the acute toxicity and the development of Acute Exposure Guideline Levels... request. ADDRESSES: The meeting will be held at the Mark Hopkins Inter- Continental Hotel, Number One Nob... Friday, excluding legal holidays. The telephone number of the EPA/DC Public Reading Room is (202) 566...

  10. Early renal effects of occupational exposure to low-level hexavalent chromium

    Energy Technology Data Exchange (ETDEWEB)

    Nagaya, Teruo (Dept. of Public Health, Gifu Univ. School of Medicine, Tsukasa-machi (Japan)); Ishikawa, Noriko (Occupational Hygiene Center, Gifu Labour Standards Association, Hikie (Japan)); Hata, Hideo (Occupational Hygiene Center, Gifu Labour Standards Association, Hikie (Japan)); Takahashi, Akemi (Gifu-shi Central Public Health Center, Miyako-dori (Japan)); Yoshida, Izumi (Gifu-shi Central Public Health Center, Miyako-dori (Japan)); Okamoto, Yoshinari (Gifu-shi Central Public Health Center, Miyako-dori (Japan))

    1994-05-01

    To detect early renal effects of occupational exposure to hexavalent chromium (Cr), urinary total proteins (U-TP), urinary albumin (U-Alb) and urinary retinol-binding protein (U-RBP) were determined in 166 male Cr platers and 106 male controls. The mean employment time in Cr plating for the platers was 12.6 years. Urinary Cr (U-Cr), which was determined as an index of Cr exposure, ranged from ''not detected'' to 19.91 [mu]g/g creatinine in the platers. The U-Cr level was lower than those in other previous studies. Age-adjusted U-TP, U-Alb or U-RBP levels were not different between the platers and the controls. In the platers, a significant positive correlation was found between age-adjusted U-TP and U-Cr, but U-Cr had no significant relation to age-adjusted U-Alb or U-RBP level. Employment time had no effect on any age-adjusted urinary proteins. The Cr exposure may have been too low to induce definite renal dysfunction. Early renal effects of low-level Cr exposure may be mild, and may not be specific to renal function. (orig.)

  11. Fluid Sounds

    DEFF Research Database (Denmark)

    Explorations and analysis of soundscapes have, since Canadian R. Murray Schafer's work during the early 1970's, developed into various established research - and artistic disciplines. The interest in sonic environments is today present within a broad range of contemporary art projects and in arch......Explorations and analysis of soundscapes have, since Canadian R. Murray Schafer's work during the early 1970's, developed into various established research - and artistic disciplines. The interest in sonic environments is today present within a broad range of contemporary art projects...... and in architectural design. Aesthetics, psychoacoustics, perception, and cognition are all present in this expanding field embracing such categories as soundscape composition, sound art, sonic art, sound design, sound studies and auditory culture. Of greatest significance to the overall field is the investigation...

  12. Occupational exposure levels of bioaerosol components are associated with serum levels of the acute phase protein Serum Amyloid A in greenhouse workers

    DEFF Research Database (Denmark)

    Madsen, Anne Mette; Thilsing, Trine; Bælum, Jesper

    2016-01-01

    to elevated levels of bioaerosols. The objective of this study is to assess whether greenhouse workers personal exposure to bioaerosol components was associated with serum levels of the acute phase proteins Serum Amyloid A (SAA) and C-reactive protein (CRP). METHODS: SAA and CRP levels were determined......-glucan. RESULTS: Serum levels of SAA and CRP were not significantly different in greenhouse workers and a reference group, or on the two work days. In a mixed model, SAA levels were positively associated with endotoxin exposure levels (p = 0.0007). Results for fungi were not clear. CRP levels were positively...... associated with endotoxin exposures (p = 0.022). Furthermore, when workers were categorized into three groups based on SAA and CRP serum levels endotoxin exposure was highest in the group with the highest SAA levels and in the group with middle and highest CRP levels. SAA and CRP levels were elevated...

  13. Estimate of safe human exposure levels for lunar dust based on comparative benchmark dose modeling.

    Science.gov (United States)

    James, John T; Lam, Chiu-Wing; Santana, Patricia A; Scully, Robert R

    2013-04-01

    Brief exposures of Apollo astronauts to lunar dust occasionally elicited upper respiratory irritation; however, no limits were ever set for prolonged exposure to lunar dust. The United States and other space faring nations intend to return to the moon for extensive exploration within a few decades. In the meantime, habitats for that exploration, whether mobile or fixed, must be designed to limit human exposure to lunar dust to safe levels. Herein we estimate safe exposure limits for lunar dust collected during the Apollo 14 mission. We instilled three respirable-sized (∼2 μ mass median diameter) lunar dusts (two ground and one unground) and two standard dusts of widely different toxicities (quartz and TiO₂) into the respiratory system of rats. Rats in groups of six were given 0, 1, 2.5 or 7.5 mg of the test dust in a saline-Survanta® vehicle, and biochemical and cellular biomarkers of toxicity in lung lavage fluid were assayed 1 week and one month after instillation. By comparing the dose--response curves of sensitive biomarkers, we estimated safe exposure levels for astronauts and concluded that unground lunar dust and dust ground by two different methods were not toxicologically distinguishable. The safe exposure estimates were 1.3 ± 0.4 mg/m³ (jet-milled dust), 1.0 ± 0.5 mg/m³ (ball-milled dust) and 0.9 ± 0.3 mg/m³ (unground, natural dust). We estimate that 0.5-1 mg/m³ of lunar dust is safe for periodic human exposures during long stays in habitats on the lunar surface.

  14. Determination of acrylamide levels in potato crisps and other snacks and exposure risk assessment through a Margin of Exposure approach.

    Science.gov (United States)

    Esposito, Francesco; Nardone, Antonio; Fasano, Evelina; Triassi, Maria; Cirillo, Teresa

    2017-10-01

    Potato crisps, corn-based extruded snacks and other savoury snacks are very popular products especially among younger generations. These products could be a potential source of acrylamide (AA), a toxic compound which could develop during frying and baking processes. The purpose of this study was the assessment of the dietary intake to AA across six groups of consumers divided according to age through the consumption of potato crisps and other snacks, in order to eventually evaluate the margin of exposure (MOE) related to neurotoxic and carcinogenic critical endpoints. Different brands of potato crisps and other popular snacks were analyzed through a matrix solid-phase dispersion method followed by a bromination step and GC-MS quantification. The concentration of detected AA ranged from 21 to 3444 ng g - 1 and the highest level occurred in potato crisps samples which showed a median value of 968 ng g - 1 . The risk characterization through MOE assessment revealed that five out of six consumers groups showed higher exposure values associated with an augmented carcinogenic risk. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Health effects of subchronic exposure to environmental levels of diesel exhaust.

    Science.gov (United States)

    Reed, M D; Gigliotti, A P; McDonald, J D; Seagrave, J C; Seilkop, S K; Mauderly, J L

    2004-04-01

    Diesel exhaust is a public health concern and contributor to both ambient and occupational air pollution. As part of a general health assessment of multiple anthropogenic source emissions conducted by the National Environmental Respiratory Center (NERC), a series of health assays was conducted on rats and mice exposed to environmentally relevant levels of diesel exhaust. This article summarizes the study design and exposures, and reports findings on several general indicators of toxicity and carcinogenic potential. Diesel exhaust was generated from a commonly used 2000 model 5.9-L, 6-cylinder turbo diesel engine operated on a variable-load heavy-duty test cycle burning national average certification fuel. Animals were exposed to clean air (control) or four dilutions of whole emissions based on particulate matter concentration (30, 100, 300, and 1000 microg/m(3)). Male and female F344 rats and A/J mice were exposed by whole-body inhalation 6 h/day, 7 days/wk, for either 1 wk or 6 mo. Exposures were characterized in detail. Effects of exposure on clinical observations, body and organ weights, serum chemistry, hematology, histopathology, bronchoalveolar lavage, and serum clotting factors were mild. Significant exposure-related effects occurring in both male and female rats included decreases in serum cholesterol and clotting Factor VII and slight increases in serum gamma-glutamyl transferase. Several other responses met screening criteria for significant exposure effects but were not consistent between genders or exposure times and were not corroborated by related parameters. Carcinogenic potential as determined by micronucleated reticulocyte counts and proliferation of adenomas in A/J mice were unaffected by 6 mo of exposure. Parallel studies demonstrated effects on cardiac function and resistance to viral infection; however, the results reported here show few and only modest health hazards from subchronic or shorter exposures to realistic concentrations of

  16. Sound Settlements

    DEFF Research Database (Denmark)

    Mortensen, Peder Duelund; Hornyanszky, Elisabeth Dalholm; Larsen, Jacob Norvig

    2013-01-01

    Præsentation af projektresultater fra Interreg forskningen Sound Settlements om udvikling af bæredygtighed i det almene boligbyggerier i København, Malmø, Helsingborg og Lund samt europæiske eksempler på best practice......Præsentation af projektresultater fra Interreg forskningen Sound Settlements om udvikling af bæredygtighed i det almene boligbyggerier i København, Malmø, Helsingborg og Lund samt europæiske eksempler på best practice...

  17. Nuclear sound

    International Nuclear Information System (INIS)

    Wambach, J.

    1991-01-01

    Nuclei, like more familiar mechanical systems, undergo simple vibrational motion. Among these vibrations, sound modes are of particular interest since they reveal important information on the effective interactions among the constituents and, through extrapolation, on the bulk behaviour of nuclear and neutron matter. Sound wave propagation in nuclei shows strong quantum effects familiar from other quantum systems. Microscopic theory suggests that the restoring forces are caused by the complex structure of the many-Fermion wavefunction and, in some cases, have no classical analogue. The damping of the vibrational amplitude is strongly influenced by phase coherence among the particles participating in the motion. (author)

  18. The effect of speaking rate on serial-order sound-level errors in normal healthy controls and persons with aphasia.

    Science.gov (United States)

    Fossett, Tepanta R D; McNeil, Malcolm R; Pratt, Sheila R; Tompkins, Connie A; Shuster, Linda I

    Although many speech errors can be generated at either a linguistic or motoric level of production, phonetically well-formed sound-level serial-order errors are generally assumed to result from disruption of phonologic encoding (PE) processes. An influential model of PE (Dell, 1986; Dell, Burger & Svec, 1997) predicts that speaking rate should affect the relative proportion of these serial-order sound errors (anticipations, perseverations, exchanges). These predictions have been extended to, and have special relevance for persons with aphasia (PWA) because of the increased frequency with which speech errors occur and because their localization within the functional linguistic architecture may help in diagnosis and treatment. Supporting evidence regarding the effect of speaking rate on phonological encoding has been provided by studies using young normal language (NL) speakers and computer simulations. Limited data exist for older NL users and no group data exist for PWA. This study tested the phonologic encoding properties of Dell's model of speech production (Dell, 1986; Dell,et al., 1997), which predicts that increasing speaking rate affects the relative proportion of serial-order sound errors (i.e., anticipations, perseverations, and exchanges). The effects of speech rate on the error ratios of anticipation/exchange (AE), anticipation/perseveration (AP) and vocal reaction time (VRT) were examined in 16 normal healthy controls (NHC) and 16 PWA without concomitant motor speech disorders. The participants were recorded performing a phonologically challenging (tongue twister) speech production task at their typical and two faster speaking rates. A significant effect of increased rate was obtained for the AP but not the AE ratio. Significant effects of group and rate were obtained for VRT. Although the significant effect of rate for the AP ratio provided evidence that changes in speaking rate did affect PE, the results failed to support the model derived predictions

  19. Exposure to pyrethroids insecticides and serum levels of thyroid-related measures in pregnant women

    International Nuclear Information System (INIS)

    Zhang, Jie; Hisada, Aya; Yoshinaga, Jun; Shiraishi, Hiroaki; Shimodaira, Kazuhisa; Okai, Takashi; Noda, Yumiko; Shirakawa, Miyako; Kato, Nobumasa

    2013-01-01

    Possible association between environmental exposure to pyrethroid insecticides and serum thyroid-related measures was explored in 231 pregnant women of 10–12 gestational weeks recruited at a university hospital in Tokyo during 2009–2011. Serum levels of free thyroxine (fT4), thyroid stimulating hormone (TSH) and thyroid biding globulin (TBG) and urinary pyrethroid insecticide metabolite (3-phenoxybenzoic acid, 3-PBA) were measured. Obstetrical information was obtained from medical records and dietary and lifestyle information was collected by self-administered questionnaire. Geometric mean concentration of creatinine-adjusted urinary 3-PBA was 0.363 (geometric standard deviation: 3.06) μg/g cre, which was consistent with the previously reported levels for non-exposed Japanese adult females. The range of serum fT4, TSH and TBG level was 0.83–3.41 ng/dL, 0.01–27.4 μIU/mL and 16.4–54.4 μg/mL, respectively. Multiple regression analysis was carried out by using either one of serum levels of thyroid-related measures as a dependent variable and urinary 3-PBA as well as other potential covariates (age, pre-pregnancy BMI, parity, urinary iodine, smoking and drinking status) as independent variables: 3-PBA was not found as a significant predictor of serum level of thyroid-related measures. Lack of association may be due to lower pyrethroid insecticide exposure level of the present subjects. Taking the ability of pyrethroid insecticides and their metabolite to bind to nuclear thyroid hormone (TH) receptor, as well as their ability of placental transfer, into consideration, it is warranted to investigate if pyrethroid pesticides do not have any effect on TH actions in fetus brain even though maternal circulating TH level is not affected. -- Highlights: • Pyrethroid exposure and thyroid hormone status was examined in pregnant women. • Urinary 3-phenoxybenzoic acid was used as a biomarker of exposure. • Iodine nutrition, age and other covariates were included

  20. Exposure to pyrethroids insecticides and serum levels of thyroid-related measures in pregnant women

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jie; Hisada, Aya [Department of Environmental Studies, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8563 (Japan); Yoshinaga, Jun, E-mail: junyosh@k.u-tokyo.ac.jp [Department of Environmental Studies, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8563 (Japan); Shiraishi, Hiroaki [National Institute for Environmental Studies, Onogawa 16-2, Tsukuba, Ibaraki 305-8563 (Japan); Shimodaira, Kazuhisa; Okai, Takashi [Department of Obstetrics and Gynecology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555 (Japan); Noda, Yumiko; Shirakawa, Miyako; Kato, Nobumasa [Department of Psychiatry and Neurology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555 (Japan)

    2013-11-15

    Possible association between environmental exposure to pyrethroid insecticides and serum thyroid-related measures was explored in 231 pregnant women of 10–12 gestational weeks recruited at a university hospital in Tokyo during 2009–2011. Serum levels of free thyroxine (fT4), thyroid stimulating hormone (TSH) and thyroid biding globulin (TBG) and urinary pyrethroid insecticide metabolite (3-phenoxybenzoic acid, 3-PBA) were measured. Obstetrical information was obtained from medical records and dietary and lifestyle information was collected by self-administered questionnaire. Geometric mean concentration of creatinine-adjusted urinary 3-PBA was 0.363 (geometric standard deviation: 3.06) μg/g cre, which was consistent with the previously reported levels for non-exposed Japanese adult females. The range of serum fT4, TSH and TBG level was 0.83–3.41 ng/dL, 0.01–27.4 μIU/mL and 16.4–54.4 μg/mL, respectively. Multiple regression analysis was carried out by using either one of serum levels of thyroid-related measures as a dependent variable and urinary 3-PBA as well as other potential covariates (age, pre-pregnancy BMI, parity, urinary iodine, smoking and drinking status) as independent variables: 3-PBA was not found as a significant predictor of serum level of thyroid-related measures. Lack of association may be due to lower pyrethroid insecticide exposure level of the present subjects. Taking the ability of pyrethroid insecticides and their metabolite to bind to nuclear thyroid hormone (TH) receptor, as well as their ability of placental transfer, into consideration, it is warranted to investigate if pyrethroid pesticides do not have any effect on TH actions in fetus brain even though maternal circulating TH level is not affected. -- Highlights: • Pyrethroid exposure and thyroid hormone status was examined in pregnant women. • Urinary 3-phenoxybenzoic acid was used as a biomarker of exposure. • Iodine nutrition, age and other covariates were included

  1. Exposure to DEHP decreased four fatty acid levels in plasma of prepartum mice

    International Nuclear Information System (INIS)

    Nakashima, Ryosuke; Hayashi, Yumi; Khalequzzaman, Md.; Jia, Xiaofang; Wang, Dong; Naito, Hisao; Ito, Yuki; Kamijima, Michihiro; Gonzalez, Frank J.; Nakajima, Tamie

    2013-01-01

    Maternal exposure to di(2-ethylhexyl) phthalate (DEHP) decreased the plasma triglyceride in prepartum mice. To identify the fatty acid (FA) species involved and to understand the underlying mechanisms, pregnant Sv/129 wild-type (mPPARα), peroxisome proliferator-activated receptor α-null (Pparα-null) and humanized PPARα (hPPARα) mice were treated with diets containing 0%, 0.01%, 0.05% or 0.1% DEHP. Dams were dissected on gestational day 18 together with fetuses, and on postnatal day 2 together with newborns. n-3/n-6 polyunsaturated, saturated, and monounsaturated FAs in maternal plasma and in liver of wild-type offspring, and representative enzymes for FA desaturation and elongation in maternal liver, were measured. The plasma levels of linoleic acid, α-linolenic acid, palmitic acid and oleic acid were higher in the pregnant control mPPARa mice than in Ppara-null and hPPARa mice. DEHP exposure significantly decreased the levels of these four FAs only in pregnant mPPARα mice. Plasma levels of many FAs were higher in pregnant mice than in postpartum ones in a genotype-independent manner, while it was lower in the livers of fetuses than pups. DEHP exposure slightly increased hepatic arachidonic acid, α-linolenic acid, palmitoleic acid and oleic acid in fetuses, but not in pups. However, DEHP exposure did not clearly influence FA desaturase 1 and 2 nor elongase 2 and 5 expressions in the liver of all maternal mice. Taken together, the levels of plasma four FAs with shorter carbon chains were higher in pregnant mPPARα mice than in other genotypes, and DEHP exposure decreased these specific FA concentrations only in mPPARα mice, similarly to triglyceride levels

  2. Consumer product exposures associated with urinary phthalate levels in pregnant women

    Science.gov (United States)

    Buckley, Jessie P.; Palmieri, Rachel T.; Matuszewski, Jeanine M.; Herring, Amy H.; Baird, Donna D.; Hartmann, Katherine E.; Hoppin, Jane A.

    2012-01-01

    Human phthalate exposure is ubiquitous, but little is known regarding predictors of urinary phthalate levels. To explore this, 50 pregnant women aged 18–38 years completed two questionnaires on potential phthalate exposures and provided a first morning void. Urine samples were analyzed for 12 phthalate metabolites. Associations with questionnaire items were evaluated via Wilcoxon tests and t-tests, and r-squared values were calculated in multiple linear regression models. Few measured factors were statistically significantly associated with phthalate levels. Individuals who used nail polish had higher levels of mono-butyl phthalate (p=0.048) than non-users. Mono-benzyl phthalate levels were higher among women who used eye makeup (p=0.034) or used makeup on a regular basis (p=0.004). Women who used cologne or perfume had higher levels of di-(2-ethylhexyl) phthalate metabolites. Household products, home flooring or paneling, and other personal care products were also associated with urinary phthalates. The proportion of variance in metabolite concentrations explained by questionnaire items ranged between 0.31 for mono-ethyl phthalate and 0.42 for mono-n-methyl phthalate. Although personal care product use may be an important predictor of urinary phthalate levels, most of the variability in phthalate exposure was not captured by our relatively comprehensive set of questionnaire items. PMID:22760436

  3. The effects of repeated low-level blast exposure on hearing in marines

    Directory of Open Access Journals (Sweden)

    Lina R Kubli

    2017-01-01

    Full Text Available Background: The study evaluates a group of Military Service Members specialized in blast explosive training called “Breachers” who are routinely exposed to multiple low-level blasts while teaching breaching at the U.S. Marine Corps in Quantico Virginia. The objective of this study was to determine if there are any acute or long-term auditory changes due to repeated low-level blast exposures used in training. The performance of the instructor group “Breachers” was compared to a control group, “Engineers”. Methods: A total of 11 Breachers and four engineers were evaluated in the study. The participants received comprehensive auditory tests, including pure-tone testing, speech-in-noise (SIN measures, and central auditory behavioral and objective tests using early and late (P300 auditory evoked potentials over a period of 17 months. They also received shorter assessments immediately following the blast-exposure onsite at Quantico. Results: No acute or longitudinal effects were identified. However, there were some interesting baseline effects found in both groups. Contrary to the expected, the onsite hearing thresholds and distortion product otoacoustic emissions were slightly better at a few frequencies immediately after blast-exposure than measurements obtained with the same equipment weeks to months after each blast-exposure. Conclusions: To date, the current study is the most comprehensive study that evaluates the long-term effects of blast-exposure on hearing. Despite extensive testing to assess changes, the findings of this study suggest that the levels of current exposures used in this military training environment do not seem to have an obvious deleterious effect on hearing.

  4. DEVELOPMENT OF DIAGNOSTIC REFERENCE LEVELS (DRL OF PATIENTS X-RAY EXPOSURE IN DIAGNOSTIC RADIOLOGY

    Directory of Open Access Journals (Sweden)

    A. V. Vodovatov

    2013-01-01

    Full Text Available We introduce a system of Diagnostic Reference Levels (DRLs for patients medical exposure for national health care practice implementation. DRLs are an effective way of the patient radiation protection through the optimization of the medical exposure. The paper discusses and compares different methods of determining the DRLs based on measured and/or calculated quantities of patient’s dose: dose area product (DAP, entrance surface dose (ESD and an effective dose. Distributions of different dose quantities in different Saint-Petersburg clinics are shown on the example of chest PA examinations. The results are compared with the data from other sources. Regional DRLs for Saint-Petersburg are proposed.

  5. Patient dose, gray level and exposure index with a computed radiography system

    Science.gov (United States)

    Silva, T. R.; Yoshimura, E. M.

    2014-02-01

    Computed radiography (CR) is gradually replacing conventional screen-film system in Brazil. To assess image quality, manufactures provide the calculation of an exposure index through the acquisition software of the CR system. The objective of this study is to verify if the CR image can be used as an evaluator of patient absorbed dose too, through a relationship between the entrance skin dose and the exposure index or the gray level values obtained in the image. The CR system used for this study (Agfa model 30-X with NX acquisition software) calculates an exposure index called Log of the Median (lgM), related to the absorbed dose to the IP. The lgM value depends on the average gray level (called Scan Average Level (SAL)) of the segmented pixel value histogram of the whole image. A Rando male phantom was used to simulate a human body (chest and head), and was irradiated with an X-ray equipment, using usual radiologic techniques for chest exams. Thermoluminescent dosimeters (LiF, TLD100) were used to evaluate entrance skin dose and exit dose. The results showed a logarithm relation between entrance dose and SAL in the image center, regardless of the beam filtration. The exposure index varies linearly with the entrance dose, but the angular coefficient is beam quality dependent. We conclude that, with an adequate calibration, the CR system can be used to evaluate the patient absorbed dose.

  6. 1-Hydroxypyrene Levels in Blood Samples of Rats After Exposure to Generator Fumes

    Science.gov (United States)

    Ifegwu, Clinton; Igwo-Ezikpe, Miriam N.; Anyakora, Chimezie; Osuntoki, Akinniyi; Oseni, Kafayat A.; Alao, Eragbae O.

    2013-01-01

    Polynuclear Aromatic Hydrocarbons (PAHs) are a major component of fuel generator fumes. Carcinogenicity of these compounds has long been established. In this study, 37 Swiss albino rats were exposed to generator fumes at varied distances for 8 hours per day for a period of 42 days and the level of 1-hydroxypyrene in their blood was evaluated. This study also tried to correlate the level of blood 1-hyroxypyrene with the distance from the source of pollution. Plasma was collected by centrifuging the whole blood sample followed by complete hydrolysis of the conjugated 1-hydroxypyrene glucuronide to yield the analyte of interest, 1-hydroxypyrene, which was achieved using beta glucuronidase. High performance liquid chromatography (HPLC) with UV detector was used to determine the 1-hydroxypyrene concentrations in the blood samples. The mobile phase was water:methanol (12:88 v/v) isocratic run at the flow rate of 1.2 mL/min with CI8 stationary phase at 250 nm. After 42 days of exposure, blood concentration level of 1-hydroxypyrene ranged from 34 μg/mL to 26.29 μg/mL depending on the distance from source of exposure. The control group had no 1-hydroxypyrene in their blood. After the period of exposure, percentage of death correlated with the distance from the source of exposure. Percentage of death ranged from 56% to zero depending on the proximity to source of pollution. PMID:24179393

  7. Effects of low-level exposure to xenobiotics present in paints on oxidative stress in workers.

    Science.gov (United States)

    Moro, Angela M; Charão, Mariele; Brucker, Natália; Bulcão, Rachel; Freitas, Fernando; Guerreiro, Gilian; Baierle, Marília; Nascimento, Sabrina; Waechter, Fernanda; Hirakata, Vânia; Linden, Rafael; Thiesen, Flávia V; Garcia, Solange Cristina

    2010-09-15

    Paints are composed of an extensive variety of hazardous substances, such as organic solvents and heavy metals. Biomonitoring is an essential tool for assessing the risk to occupational health. Thus, this study analyzed the levels of biomarkers of exposure for toluene, xylene, styrene, ethylbenzene, and lead, as well as the oxidative stress biomarker alterations in painters of an industry. Lipid peroxidation biomarker (MDA), delta-aminolevulinate dehydratase (ALA-D), nonprotein thyol groups, superoxide dismutase and catalase (CAT) were analyzed in exposed and nonexposed subjects. We estimated which of the paint constituents have the greatest influence on the changes in the biomarkers of oxidative stress in this case of co-exposure. The results demonstrated that despite the fact that all the biomarkers of exposure were below the biological exposure limits, the MDA levels and antioxidant enzyme activities were increased, while nonprotein thyol groups and ALA-D levels were decreased in painters when compared with nonexposed subjects. After statistic test, toluene could be suggested as the principal factor responsible for increased lipid peroxidation and inhibition of ALA-D enzyme; however, further studies on the inhibition of ALA-D enzyme by toluene are necessary. Copyright 2010 Elsevier B.V. All rights reserved.

  8. Producing of Impedance Tube for Measurement of Acoustic Absorption Coefficient of Some Sound Absorber Materials

    Directory of Open Access Journals (Sweden)

    R. Golmohammadi

    2008-04-01

    Full Text Available Introduction & Objective: Noise is one of the most important harmful agents in work environment. In spit of industrial improvements, exposure with over permissible limit of noise is counted as one of the health complication of workers. In Iran, do not exact information of the absorption coefficient of acoustic materials. Iranian manufacturer have not laboratory for measured of sound absorbance of their products, therefore using of sound absorber is limited for noise control in industrial and non industrial constructions. The goal of this study was to design an impedance tube based on pressure method for measurement of the sound absorption coefficient of acoustic materials.Materials & Methods: In this study designing of measuring system and method of calculation of sound absorption based on a available equipment and relatively easy for measurement of the sound absorption coefficient related to ISO10534-1 was performed. Measuring system consist of heavy asbestos tube, a pure tone sound generator, calibrated sound level meter for measuring of some commonly of sound absorber materials was used. Results: In this study sound absorption coefficient of 23 types of available acoustic material in Iran was tested. Reliability of results by three repeat of measurement was tested. Results showed that the standard deviation of sound absorption coefficient of study materials was smaller than .Conclusion: The present study performed a necessary technology of designing and producing of impedance tube for determining of acoustical materials absorption coefficient in Iran.

  9. The influence of environmental sound training on the perception of spectrally degraded speech and environmental sounds.

    Science.gov (United States)

    Shafiro, Valeriy; Sheft, Stanley; Gygi, Brian; Ho, Kim Thien N

    2012-06-01

    Perceptual training with spectrally degraded environmental sounds results in improved environmental sound identification, with benefits shown to extend to untrained speech perception as well. The present study extended those findings to examine longer-term training effects as well as effects of mere repeated exposure to sounds over time. Participants received two pretests (1 week apart) prior to a week-long environmental sound training regimen, which was followed by two posttest sessions, separated by another week without training. Spectrally degraded stimuli, processed with a four-channel vocoder, consisted of a 160-item environmental sound test, word and sentence tests, and a battery of basic auditory abilities and cognitive tests. Results indicated significant improvements in all speech and environmental sound scores between the initial pretest and the last posttest with performance increments following both exposure and training. For environmental sounds (the stimulus class that was trained), the magnitude of positive change that accompanied training was much greater than that due to exposure alone, with improvement for untrained sounds roughly comparable to the speech benefit from exposure. Additional tests of auditory and cognitive abilities showed that speech and environmental sound performance were differentially correlated with tests of spectral and temporal-fine-structure processing, whereas working memory and executive function were correlated with speech, but not environmental sound perception. These findings indicate generalizability of environmental sound training and provide a basis for implementing environmental sound training programs for cochlear implant (CI) patients.

  10. Sound Settlements

    DEFF Research Database (Denmark)

    Mortensen, Peder Duelund; Hornyanszky, Elisabeth Dalholm; Larsen, Jacob Norvig

    2013-01-01

    Præsentation af projektresultater fra Interreg forskningen Sound Settlements om udvikling af bæredygtighed i det almene boligbyggerier i København, Malmø, Helsingborg og Lund samt europæiske eksempler på best practice...

  11. Second Sound

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 6. Second Sound - The Role of Elastic Waves. R Srinivasan. General Article Volume 4 Issue 6 June 1999 pp 15-19. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/004/06/0015-0019 ...

  12. Improved inhalation technology for setting safe exposure levels for workplace chemicals

    Science.gov (United States)

    Stuart, Bruce O.

    1993-01-01

    Threshold Limit Values recommended as allowable air concentrations of a chemical in the workplace are often based upon a no-observable-effect-level (NOEL) determined by experimental inhalation studies using rodents. A 'safe level' for human exposure must then be estimated by the use of generalized safety factors in attempts to extrapolate from experimental rodents to man. The recent development of chemical-specific physiologically-based toxicokinetics makes use of measured physiological, biochemical, and metabolic parameters to construct a validated model that is able to 'scale-up' rodent response data to predict the behavior of the chemical in man. This procedure is made possible by recent advances in personal computer software and the emergence of appropriate biological data, and provides an analytical tool for much more reliable risk evaluation and airborne chemical exposure level setting for humans.

  13. Effects of low-level blast exposure on the nervous system: Is there really a controversy?

    Directory of Open Access Journals (Sweden)

    Gregory A Elder

    2014-12-01

    Full Text Available High-pressure blast waves can cause extensive CNS injury in humans. However, in combat settings such as Iraq and Afghanistan, lower level exposures associated with mild TBI (mTBI or subclinical exposure have been much more common. Yet controversy exists concerning what traits can be attributed to low-level blast, in large part due to the difficulty of distinguishing blast-related mTBI from post-traumatic stress disorder (PTSD. We describe how TBI is defined in humans and the problems posed in using current definitions to recognize blast-related mTBI. We next consider the problem of applying definitions of human mTBI to animal models, in particular that TBI severity in humans is defined in relation to alteration of consciousness at the time of injury, which typically cannot be assessed in animals. However, based on outcome assessments a condition of low-level blast exposure can be defined in animals that likely approximates human mTBI or subclinical exposure. We review blast injury modeling in animals noting that inconsistencies in experimental approach have contributed to uncertainty over the effects of low-level blast. Yet animal studies show that low-level blast pressure waves are transmitted to the brain. In brain low-level blast exposures cause behavioral, biochemical, pathological and physiological effects on the nervous system including the induction of PTSD-related behavioral traits in the absence of a psychological stressor. We review the relationship of blast exposure to chronic neurodegenerative diseases noting the paradoxical lowering of Abeta by blast, which along with other observations suggest that blast-related TBI is pathophysiologically distinct from non-blast TBI. Human neuroimaging studies show that blast-related mTBI is associated with a variety of chronic effects that are unlikely to be explained by co-morbid PTSD. We conclude that abundant evidence supports low-level blast as having long-term effects on the nervous system.

  14. Effect of nutritional state on Hsp60 levels in the rotifer Brachionus plicatilis following toxicant exposure.

    Science.gov (United States)

    Wheelock, C E; Baumgartner, T A; Newman, J W; Wolfe, M F; Tjeerdema, R S

    2002-11-13

    The nutritional state of an organism can affect the results of toxicity testing. Here we exemplified this fact by examining the effect of nutritional deprivation on heat shock protein 60 (hsp60) production in the rotifer Brachionus plicatilis following exposure to two proven inducers of hsp60, a water-accommodated fraction of crude oil (WAF) and a dispersed oil preparation (DO). Both DO and WAF exposures of unfed rotifers resulted in significantly greater hsp60 levels than that of fed DO and WAF exposed rotifers at 8 h: 870 and 3100% of control, respectively. Results clearly demonstrate that a poor nutritional state potentiates stress protein induction upon exposure to water-soluble petroleum products. It is therefore critical to define the organismal nutritional status when reporting toxic responses. Copyright 2002 Elsevier Science B.V.

  15. [Assessment for effect of low level lead-exposure on neurobehavior in workers of printing house].

    Science.gov (United States)

    Niu, Q; Dai, F; Chen, Y

    1998-11-30

    WHO Neurobehavioral Core Test Battery (NCTB) was conducted among 28 lead-exposed workers (mean age 24.84, SD2.85) in printing house and 46 controls (mean age 22.78, SD1.45), in order to assess whether low level lead exposure may be related to neurobehavioral dysfunction. The items of test were: 1. Profile of mood state(POMS), (2) Simple reaction time, (3) Digit span, (4) Santa Anna manual dexterity, (5) Digit simbol, (6) Benton visual retention; and Prusuit aiming test. In all the NCTB test values, there was no significant difference between two groups. Multiple stepwise regression analysis shows that exposure duration is related to neurobehavior scores. Mild lead exposure may affect neurobehavior in some degree but not significant.

  16. Elevated lead levels from e-waste exposure are linked to decreased olfactory memory in children.

    Science.gov (United States)

    Zhang, Bo; Huo, Xia; Xu, Long; Cheng, Zhiheng; Cong, Xiaowei; Lu, Xueling; Xu, Xijin

    2017-12-01

    Lead (Pb) is a developmental neurotoxicant and can cause abnormal development of the nervous system in children. Hence, the aim of this study was to investigate the effect of Pb exposure on child olfactory memory by correlating the blood Pb levels of children in Guiyu with olfactory memory tests. We recruited 61 preschool children, 4- to 7-years of age, from Guiyu and 57 children from Haojiang. The mean blood Pb level of Guiyu children was 9.40 μg/dL, significantly higher than the 5.04 μg/dL mean blood Pb level of Haojiang children. In addition, approximately 23% of Guiyu children had blood Pb levels exceeding 10.00 μg/dL. The correlation analysis showed that blood Pb levels in children highly correlated with e-waste contact (r s  = 0.393). Moreover, the mean concentration of serum BDNF in Guiyu children (35.91 ng/ml) was higher than for Haojiang (28.10 ng/ml) and was positively correlated with blood Pb levels. Both item and source olfactory memory tests at 15 min, 5 h and 24 h after odor exposure showed that scores were lower in Guiyu children indicative of reduced olfactory memory in Guiyu children. Olfactory memory tests scores negatively correlated with blood Pb and serum BDNF levels, but were positively associated with parental education levels. At the same time, scores of both tests on children in the high blood Pb level group (blood Pb levels > 5.00 μg/dL) were lower than those in the low blood Pb level group (blood Pb levels ≤ 5.00 μg/dL), implying that Pb exposure decreases olfactory memory in children. Our findings suggest that Pb exposure in e-waste recycling and dismantling areas could result in an increase in serum BDNF level and a decrease in child olfactory memory, in addition, BDNF might be involved in olfactory memory impairment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Kriged and modeled ambient air levels of benzene in an urban environment: an exposure assessment study

    Directory of Open Access Journals (Sweden)

    Lai Dejian

    2011-03-01

    Full Text Available Abstract Background There is increasing concern regarding the potential adverse health effects of air pollution, particularly hazardous air pollutants (HAPs. However, quantifying exposure to these pollutants is problematic. Objective Our goal was to explore the utility of kriging, a spatial interpolation method, for exposure assessment in epidemiologic studies of HAPs. We used benzene as an example and compared census tract-level kriged predictions to estimates obtained from the 1999 U.S. EPA National Air Toxics Assessment (NATA, Assessment System for Population Exposure Nationwide (ASPEN model. Methods Kriged predictions were generated for 649 census tracts in Harris County, Texas using estimates of annual benzene air concentrations from 17 monitoring sites operating in Harris and surrounding counties from 1998 to 2000. Year 1999 ASPEN modeled estimates were also obtained for each census tract. Spearman rank correlation analyses were performed on the modeled and kriged benzene levels. Weighted kappa statistics were computed to assess agreement between discretized kriged and modeled estimates of ambient air levels of benzene. Results There was modest correlation between the predicted and modeled values across census tracts. Overall, 56.2%, 40.7%, 31.5% and 28.2% of census tracts were classified as having 'low', 'medium-low', 'medium-high' and 'high' ambient air levels of benzene, respectively, comparing predicted and modeled benzene levels. The weighted kappa statistic was 0.26 (95% confidence interval (CI = 0.20, 0.31, indicating poor agreement between the two methods. Conclusions There was a lack of concordance between predicted and modeled ambient air levels of benzene. Applying methods of spatial interpolation for assessing exposure to ambient air pollutants in health effect studies is hindered by the placement and number of existing stationary monitors collecting HAP data. Routine monitoring needs to be expanded if we are to use these data

  18. Cigarettes with different nicotine levels affect sensory perception and levels of biomarkers of exposure in adult smokers.

    Science.gov (United States)

    McKinney, Diana L; Frost-Pineda, Kimberly; Oldham, Michael J; Fisher, Michael T; Wang, Jingzhu; Gogova, Maria; Kobal, Gerd

    2014-07-01

    Few clinical studies involving cigarettes have provided a comprehensive picture of smoke exposure, test article characterization, and insights into sensory properties combined. The purpose of these pilot studies was to determine whether cigarettes with different levels of nicotine but similar tar levels would affect sensory experience or smoking behavior so as to significantly alter levels of selected biomarkers of exposure (BOE). In 2 confined, double-blind studies, 120 adult smokers switched from Marlboro Gold cigarettes at baseline to either 1 of 2 lower nicotine cigarettes or 1 of 2 higher nicotine cigarettes and then to the other cigarette after 5 days. Urinary excretion of exposure biomarkers (nicotine equivalents [NE], total and free 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol [NNAL], 1-hydroxypyrene, and 3-hydroxypropyl mercapturic acid) as well as carboxyhemoglobin and plasma cotinine were measured at baseline, Day 5, and Day 10. Daily cigarette consumption was monitored and sensory characteristics were rated for each cigarette. With higher nicotine yield, urine NE, urine total NNAL, and plasma cotinine increased while nonnicotine BOE decreased without changes in cigarette consumption. In contrast, with lower nicotine yield, urine NE, urine total NNAL, and plasma cotinine dropped while nonnicotine BOE and cigarettes per day increased. Higher nicotine cigarettes were rated harsher and stronger than at baseline while lower nicotine cigarettes were less strong. All 4 test cigarettes were highly disliked. These studies demonstrate that abrupt increases or decreases in nicotine and the resulting sensory changes impact BOE through changes in intensity or frequency of smoking. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Benzene metabolite levels in blood and bone marrow of B6C3F{sub 1} mice after low-level exposure

    Energy Technology Data Exchange (ETDEWEB)

    Bechtold, W.E.; Strunk, M.R.; Thornton-Manning, J.R. [and others

    1995-12-01

    Studies at the Inhalation Toxicology Research Institute (ITRI) have explored the species-specific uptake and metabolism of benzene. Results have shown that metabolism is dependent on both dose and route of administration. Of particular interest were shifts in the major metabolic pathways as a function of exposure concentration. In these studies, B6C3F{sub 1} mice were exposed to increasing levels of benzene by either gavage or inhalation. As benzene internal dose increased, the relative amounts of muconic acid and hydroquinone decreased. In contrast, the relative amount of catechol increased with increasing exposure. These results show that the relative levels of toxic metabolites are a function of exposure level. Based on these results and assuming a linear relationship between exposure concentration and levels of bone marrow metabolites, it would be difficult to detect an elevation of any phenolic metabolites above background after occupational exposures to the OSHA Permissible Exposure Limit of 1 ppm benzene.

  20. Effects of low-level sarin and cyclosarin exposure on hippocampal subfields in Gulf War Veterans.

    Science.gov (United States)

    Chao, Linda L; Kriger, Stephen; Buckley, Shannon; Ng, Peter; Mueller, Susanne G

    2014-09-01

    More than 100,000 US troops were potentially exposed to chemical warfare agents sarin (GB) and cyclosarin (GF) when an ammunition dump at Khamisiyah, Iraq was destroyed during the 1991 Gulf War (GW). We previously reported reduced hippocampal volume in GW veterans with suspected GB/GF exposure relative to matched, unexposed GW veterans estimated from 1.5T magnetic resonance images (MRI). Here we investigate, in a different cohort of GW veterans, whether low-level GB/GF exposure is associated with structural alterations in specific hippocampal subfields, estimated from 4T MRI. The Automatic Segmentation of Hippocampal Subfields (ASHS) technique was used to quantify CA1, CA2, CA3 and dentate gyrus (DG), and subiculum (SUB) subfields volumes from high-resolution T2-weighted images acquired on a 4T MR scanner in 56 GW veterans with suspected GB/GF exposure and 56 "matched" unexposed GW veterans (mean age 49±7 years). GB/GF exposed veterans had smaller CA2 (p=0.003) and CA3/DG (p=0.01) subfield volumes compared to matched, unexposed GW veterans. There were no group difference in total hippocampal volume, quantified with FreeSurfer, and no dose-response relationship between estimated levels of GB/GF exposure and total hippocampal or subfield volume. These findings extend our previous report of structural alterations in the hippocampi of GW veterans with suspected GB/GF exposure to volume changes in the CA2, CA3, and DG hippocampal subfields in a different cohort of GW veterans with suspected GB/GF exposure. Published by Elsevier B.V.

  1. Occurrence of 210Po and Biological Effects of Low-Level Exposure: The Need for Research

    Science.gov (United States)

    Wiemels, Joseph L.

    2012-01-01

    Background: Polonium-210 (210Po) concentrations that exceed 1 Bq/L in drinking-water supplies have been reported from four widely separated U.S. states where exposure to it went unnoticed for decades. The radionuclide grandparents of 210Po are common in sediments, and segments of the public may be chronically exposed to low levels of 210Po in drinking water or in food products from animals raised in contaminated areas. Objectives: We summarized information on the environmental behavior, biokinetics, and toxicology of 210Po and identified the need for future research. Methods: Potential linkages between environmental exposure to 210Po and human health effects were identified in a literature review. Discussion: 210Po accumulates in the ovaries where it kills primary oocytes at low doses. Because of its radiosensitivity and tendency to concentrate 210Po, the ovary may be the critical organ in determining the lowest injurious dose for 210Po. 210Po also accumulates in the yolk sac of the embryo and in the fetal and placental tissues. Low-level exposure to 210Po may have subtle, long-term biological effects because of its tropism towards reproductive and embryonic and fetal tissues where exposure to a single alpha particle may kill or damage critical cells. 210Po is present in cigarettes and maternal smoking has several effects that appear consistent with the toxicology of 210Po. Conclusions: Much of the important biological and toxicological research on 210Po is more than four decades old. New research is needed to evaluate environmental exposure to 210Po and the biological effects of low-dose exposure to it so that public health officials can develop appropriate mitigation measures where necessary. PMID:22538346

  2. Levels of oxylipins, endocannabinoids and related lipids in plasma before and after low-level exposure to acrolein in healthy individuals and individuals with chemical intolerance.

    Science.gov (United States)

    Claeson, Anna-Sara; Gouveia-Figueira, Sandra; Häggström, Jenny; Fowler, Christopher J; Nording, Malin L

    2017-06-01

    Oxylipins and endocannabinoids play important biological roles, including effects upon inflammation. It is not known whether the circulating levels of these lipids are affected by inhalation of the environmental pollutant acrolein. In the present study, we have investigated the consequences of low-level exposure to acrolein on oxylipin, endocannabinoid and related lipid levels in the plasma of healthy individuals and individuals with chemical intolerance (CI), an affliction with a suggested inflammatory origin. Participants were exposed twice (60min) to heptane and a mixture of heptane and acrolein. Blood samples were collected before exposure, after and 24h post-exposure. There were no overt effects of acrolein exposure on the oxylipin lipidome or endocannibinoids detectable in the bloodstream at the time points investigated. No relationship between basal levels or levels after exposure to acrolein and CI could be identified. This implicates a minor role of inflammatory mediators on the systemic level in CI. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Toxicity levels to humans during acute exposure to hydrogen fluoride - An update

    Energy Technology Data Exchange (ETDEWEB)

    Halton, D M

    1995-09-01

    In March 1993, the Atomic Energy Control Board (AECB) commissioned and update of a 1984 review on the acute toxicity of hydrogen fluoride (HF). The study places particular emphasis on the effects of inhalation of gaseous HF and is divided into two main parts: a literature review and a lethal concentration (LC) estimation. The literature review summarizes data under four categories: animal studies, controlled human studies, community exposure, and industrial exposure. Data in these areas were critically reviewed for their relevance to lethal concentrations at LC{sub LO}, LC{sub 10} and LC{sub 50} levels that were derived in the 1984 report. In the last ten years, only one relevant animal study has been published. No new controlled human studies were found but a community exposure incident was reported. There were three new industrial/accidental exposures reported since 1984. Evaluation of new data does not change the lethal concentration estimates made in the 1984 report, but does indicate the absence of appropriate models to estimate the lethality of irritant and corrosive gases. In the last 10 years, much literature on the evaluation of major hazards has been published and suggests that such assessments are of growing political, economic and social importance. Numerous articles have been published on the acute toxicity of HF from skin contact and chronic toxicity from repeated airborne exposure. These publications offer important insights into the nature of HF toxicity. Several avenues of investigative research are suggested. (author). 55 refs., 4 tabs.

  4. Toxicity levels to humans during acute exposure to hydrogen fluoride - An update

    International Nuclear Information System (INIS)

    Halton, D.M.

    1995-09-01

    In March 1993, the Atomic Energy Control Board (AECB) commissioned and update of a 1984 review on the acute toxicity of hydrogen fluoride (HF). The study places particular emphasis on the effects of inhalation of gaseous HF and is divided into two main parts: a literature review and a lethal concentration (LC) estimation. The literature review summarizes data under four categories: animal studies, controlled human studies, community exposure, and industrial exposure. Data in these areas were critically reviewed for their relevance to lethal concentrations at LC LO , LC 10 and LC 50 levels that were derived in the 1984 report. In the last ten years, only one relevant animal study has been published. No new controlled human studies were found but a community exposure incident was reported. There were three new industrial/accidental exposures reported since 1984. Evaluation of new data does not change the lethal concentration estimates made in the 1984 report, but does indicate the absence of appropriate models to estimate the lethality of irritant and corrosive gases. In the last 10 years, much literature on the evaluation of major hazards has been published and suggests that such assessments are of growing political, economic and social importance. Numerous articles have been published on the acute toxicity of HF from skin contact and chronic toxicity from repeated airborne exposure. These publications offer important insights into the nature of HF toxicity. Several avenues of investigative research are suggested. (author). 55 refs., 4 tabs

  5. Natural radiation external exposures levels in Chilean Sub-Antarctic and country stations

    International Nuclear Information System (INIS)

    Stuardo, E.

    1988-01-01

    Since 1983 gamma exposures levels, at 1,5 m above the soil are being investigated using TLD detectors. A network of 12 stations have been established from ARICA (18 deg 20' S latitude) in Northern Chile to YELCHO (64 deg 52' S latitude) in Antartic territory. One year monitoring period was used at Antartic stations and a four months period in the country. The main subject of this study is to assess the average background radiation levels along the territory which is relevant to get a reference level and specially an estimate of the average natural radiation contribution to the population dose in Southern Chile

  6. Legal recourse for damages suffered from low-level radiation exposure

    International Nuclear Information System (INIS)

    Pesto-Edwards, M.M.

    1984-01-01

    In the past few years several events involving toxic substances have received widespread coverage by the media, thereby altering an already aware population to the hazards of exposure to toxic agents. Incidents such as Three Mile Islane, Love Canal, and Hemlock, Michigan, the exposure plight of veterans to radiation at the Nevada Test Site and to Agent Orange in Vietnam, and to the exposure of factory workers to asbestos, have been highly publicized. In part because of this publicity, the emphasis of the 1970's on controlling water and air pollution has been shifting slowly during the 1980s to the of control of hazardous waste pollution. Despite this shifting emphasis, legislative and judicial systems have been slow to respond. Few remedies are available to real and imagined victims of toxic substances. From a legal point of view, there is little difference between exposure to low levels of radiation and low levels of toxic chemicals. Both instances fall under the broader domain of environmental law. Depending on the circumstances, one instance might provide legal precedent for the other. This chapter presents examples drawn from both areas in order to illustrate current issues. The discussion is divided into four parts: (1) the common law tort theories that may be asserted when a plaintiff has suffered injury resulting from exposure to low-level radiation or other toxic substances; (2) the difficulties posed by the relief mechanisms rooted in traditional common law; (3) current federal legislation, along with its merits and shortcomings; and (4) solutions to the obstacles now faced by plaintiffs in attempting to recover their damages. Also discussed are suggested judicial and legislative solutions designed to remedy the damages caused to persons exposed to toxic wastes

  7. Modeling the transmitted and stored energy in multilayer protective clothing under low-level radiant exposure

    International Nuclear Information System (INIS)

    Su, Yun; He, Jiazhen; Li, Jun

    2016-01-01

    Highlights: • A numerical model from heating source to skin tissues through multilayer fabric system is developed. • The numerical model is comprehensively validated with experimental data. • The model is used to investigate the relationship between the transmitted and stored energy and the influencing factors. - Abstract: A finite difference model was introduced to simulate the transmitted and stored energy in firefighters' protective clothing exposed to low-level thermal radiation. The model domain consists of a three-layer fire-resistant fabric system (outer shell, moisture barrier, and thermal liner), the human skin, and the air gap between clothing and the skin. The model accounted for the relationship between the transmitted heat during the exposure and the discharged heat during the cooling-down period. The numerical model predictions were compared with experimental data. Additionally, the parameters that affect the transmitted and stored energy of protective clothing were investigated. The results demonstrate that for the typical multilayer firefighter protective clothing, the transmitted heat during exposure and the discharged heat after exposure totally determine the skin burn under low-level heat exposure, especially for third-degree skin burns. The findings obtained in this study can be used to engineer fabric systems that provide better protection for the stored thermal burn.

  8. Storage phosphor radiography of wrist fractures: a subjective comparison of image quality at varying exposure levels

    Energy Technology Data Exchange (ETDEWEB)

    Peer, Regina; Giacomuzzi, Salvatore M.; Bodner, Gerd; Jaschke, Werner; Peer, Siegfried [Innsbruck Univ. (Austria). Inst. fuer Radiologie; Lanser, Anton [Academy of Radiology Technicians, Innsbruck (Austria); Pechlaner, Sigurd [Department of Traumatology, University Hospital, Innsbruck (Austria); Kuenzel, Karl Heinz; Gaber, O. [Department of Anatomy and Histology, University Hospital, Innsbruck (Austria)

    2002-06-01

    Image quality of storage phosphor radiographs acquired at different exposure levels was compared to define the minimal radiation dose needed to achieve images which allow for reliable detection of wrist fractures. In a study on 33 fractured anatomical wrist specimens image quality of storage phosphor radiographs was assessed on a diagnostic PACS workstation by three observers. Images were acquired at exposure levels corresponding to a speed classes 100, 200, 400 and 800. Cortical bone surface, trabecular bone, soft tissues and fracture delineation were judged on a subjective basis. Image quality was rated according to a standard protocol and statistical evaluation was performed based on an analysis of variance (ANOVA). Images at a dose reduction of 37% were rated sufficient quality without loss in diagnostic accuracy. Sufficient trabecular and cortical bone presentation was still achieved at a dose reduction of 62%. The latter images, however, were considered unacceptable for fracture detection. To achieve high-quality storage phosphor radiographs, which allow for a reliable evaluation of wrist fractures, a minimum exposure dose equivalent to a speed class of 200 is needed. For general-purpose skeletal radiography, however, a dose reduction of up to 62% can be achieved. A choice of exposure settings according to the clinical situation (ALARA principle) is recommended to achieve possible dose reductions. (orig.)

  9. Rat hippocampal alterations could underlie behavioral abnormalities induced by exposure to moderate noise levels.

    Science.gov (United States)

    Uran, S L; Aon-Bertolino, M L; Caceres, L G; Capani, F; Guelman, L R

    2012-08-30

    Noise exposure is known to affect auditory structures in living organisms. However, it should not be ignored that many of the effects of noise are extra-auditory. Previous findings of our laboratory demonstrated that noise was able to induce behavioral alterations that are mainly related to the cerebellum (CE) and the hippocampus (HC). Therefore, the aim of this work was to reveal new data about the vulnerability of developing rat HC to moderate noise levels through the assessment of potential histological changes and hippocampal-related behavioral alterations. Male Wistar rats were exposed to noise (95-97 dB SPL, 2h daily) either for 1 day (acute noise exposure, ANE) or between postnatal days 15 and 30 (sub-acute noise exposure, SANE). Hippocampal histological evaluation as well as short (ST) and long term (LT) habituation and recognition memory assessments were performed. Results showed a mild disruption in the different hippocampal regions after ANE and SANE schemes, along with significant behavioral abnormalities. These data suggest that exposure of developing rats to noise levels of moderate intensity is able to trigger changes in the HC, an extra-auditory structure of the Central Nervous System (CNS), that could underlie the observed behavioral effects. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Excitation of high energy levels under laser exposure of suspensions of nanoparticles in liquids

    Energy Technology Data Exchange (ETDEWEB)

    Shafeev, G.A. [Wave Research Center of A.M. Prokhorov General Physics Institute, 38, Vavilov Street, 119991 Moscow (Russian Federation)], E-mail: shafeev@kapella.gpi.ru; Simakin, A.V. [Wave Research Center of A.M. Prokhorov General Physics Institute, 38, Vavilov Street, 119991 Moscow (Russian Federation); Bozon-Verduraz, F. [ITODYS, UMR CNRS 7086, Universite Paris 7-Denis Diderot, 2, place Jussieu, 75251 Paris cedex 05 (France); Robert, M. [Laboratoire d' Electrochimie Moleculaire, UMR CNRS 7591, Universite Paris 7 Denis Diderot, 2, place Jussieu, 75251 Paris cedex 05 (France)

    2007-12-15

    Laser exposure of suspensions of nanoparticles in liquids leads to excitation of high energy levels in both liquid and nanoparticle material. The emission spectrum of the colloidal solution under exposure of a suspension metallic nanoparticles in water to radiation of a Nd:YAG laser of a picosecond range of pulse duration is discussed. Excitation of nuclear energy levels and neutron release is experimentally studied on the model system of transmutation of Hg into Au that occurs under exposure of Hg nanodrops suspended in D{sub 2}O. The proposed mechanism involves: (i) emission of X-ray photons by Hg nanoparticles upon laser exposure, leading to neutron release from D{sub 2}O, (ii) initiation of Hg {yields} Au transmutation by the capture of neutrons. The effect of transmutation is more pronounced using {sup 196}Hg isotope instead of Hg of natural isotope composition. The influence of laser pulse duration on the degree of transmutation (from fs through ns range) is discussed.

  11. LEA: An Algorithm to Estimate the Level of Location Exposure in Infrastructure-Based Wireless Networks

    Directory of Open Access Journals (Sweden)

    Francisco Garcia

    2017-01-01

    Full Text Available Location privacy in wireless networks is nowadays a major concern. This is due to the fact that the mere fact of transmitting may allow a network to pinpoint a mobile node. We consider that a first step to protect a mobile node in this situation is to provide it with the means to quantify how accurately a network establishes its position. To achieve this end, we introduce the location-exposure algorithm (LEA, which runs on the mobile terminal only and whose operation consists of two steps. In the first step, LEA discovers the positions of nearby network nodes and uses this information to emulate how they estimate the position of the mobile node. In the second step, it quantifies the level of exposure by computing the distance between the position estimated in the first step and its true position. We refer to these steps as a location-exposure problem. We tested our proposal with simulations and testbed experiments. These results show the ability of LEA to reproduce the location of the mobile node, as seen by the network, and to quantify the level of exposure. This knowledge can help the mobile user decide which actions should be performed before transmitting.

  12. Low-level exposure of guinea pigs and marmosets to sarin vapour in air: Lowest-observable-adverse-effect level (LOAEL) for miosis

    NARCIS (Netherlands)

    Helden, H.P.M. van; Trap, H.C.; Kuijpers, W.C.; Oostdijk, J.P.; Benschop, H.P.; Langenberg, J.P.

    2004-01-01

    The purpose of this pilot study was to indicate, for low-level exposure of conscious guinea pigs and marmoset monkeys to sarin vapour in air, the lowest-observable-adverse-effect level (LOAEL) of sarin for miosis. This is the concentration × time (C·t) value (t = 5 h) of exposure at which miosis

  13. The Association between Exposure to Environmental Bisphenol A and Gonadotropic Hormone Levels among Men.

    Directory of Open Access Journals (Sweden)

    Hong Liang

    Full Text Available Bisphenol A (BPA is an extensively used chemical with endocrine disrupting properties. Although animal and in vivo studies have suggested possible effects of BPA on levels of gonadotropic hormones, human studies are limited and inconclusive. The study examined whether environmental BPA exposure was associated with gonadotropic hormones levels in men. A total of 560 men aged 18-55 years were recruited from Sandu County, Guizhou Province, China. We collected urine samples for measurement of BPA, and blood samples for measurement of reproductive hormones. We examined serum levels of follicle-stimulating hormone (FSH, luteinizing hormone (LH, and total testosterone (T. Relative risk (RR was obtained by log-binominal regression to explore the association between urinary BPA level and hormone levels. BPA was detected in 70.4% of urine samples, with a geometric mean of 0.50 μg/gCr. Men with detectable levels of BPA had a 1.52-fold increased risk of having a high LH level (>75th percentile when compared with men with undetectable levels of BPA, after adjustment for potential confounders (95% confidence interval (CI: 1.04-2.21. The association persisted and slightly intensified among current smokers (adjusted RR (aRR = 1.76, 95%CI: 1.05-2.95, while it weakened among non-smokers (aRR = 1.17, 95%CI: 0.69-1.96. Urinary BPA level was associated with an increased FSH level among smokers (aRR = 1.64, 95%CI: 1.01-2.67. Urinary BPA level was inversely associated with total T level among males with body max index (BMI ≥25 kg/m2 although this association was of borderline significance (aRR = 0.52, 95%CI: 0.26-1.05. In conclusion, environmental exposure to BPA was associated with increased serum levels of LH and FSH in male smokers, along with decreased serum levels of total T in men with BMI≥25 kg/m2. These findings suggest that the effects of environmental BPA exposure on hormone levels might be modified by smoking and BMI.

  14. PREFACE: Aerodynamic sound Aerodynamic sound

    Science.gov (United States)

    Akishita, Sadao

    2010-02-01

    The modern theory of aerodynamic sound originates from Lighthill's two papers in 1952 and 1954, as is well known. I have heard that Lighthill was motivated in writing the papers by the jet-noise emitted by the newly commercialized jet-engined airplanes at that time. The technology of aerodynamic sound is destined for environmental problems. Therefore the theory should always be applied to newly emerged public nuisances. This issue of Fluid Dynamics Research (FDR) reflects problems of environmental sound in present Japanese technology. The Japanese community studying aerodynamic sound has held an annual symposium since 29 years ago when the late Professor S Kotake and Professor S Kaji of Teikyo University organized the symposium. Most of the Japanese authors in this issue are members of the annual symposium. I should note the contribution of the two professors cited above in establishing the Japanese community of aerodynamic sound research. It is my pleasure to present the publication in this issue of ten papers discussed at the annual symposium. I would like to express many thanks to the Editorial Board of FDR for giving us the chance to contribute these papers. We have a review paper by T Suzuki on the study of jet noise, which continues to be important nowadays, and is expected to reform the theoretical model of generating mechanisms. Professor M S Howe and R S McGowan contribute an analytical paper, a valuable study in today's fluid dynamics research. They apply hydrodynamics to solve the compressible flow generated in the vocal cords of the human body. Experimental study continues to be the main methodology in aerodynamic sound, and it is expected to explore new horizons. H Fujita's study on the Aeolian tone provides a new viewpoint on major, longstanding sound problems. The paper by M Nishimura and T Goto on textile fabrics describes new technology for the effective reduction of bluff-body noise. The paper by T Sueki et al also reports new technology for the

  15. A quantitative screening-level approach to incorporate chemical exposure and risk into alternative assessment evaluations.

    Science.gov (United States)

    Arnold, Scott M; Greggs, Bill; Goyak, Katy O; Landenberger, Bryce D; Mason, Ann M; Howard, Brett; Zaleski, Rosemary T

    2017-11-01

    As the general public and retailers ask for disclosure of chemical ingredients in the marketplace, a number of hazard screening tools were developed to evaluate the so-called "greenness" of individual chemical ingredients and/or formulations. The majority of these tools focus only on hazard, often using chemical lists, ignoring the other part of the risk equation: exposure. Using a hazard-only focus can result in regrettable substitutions, changing 1 chemical ingredient for another that turns out to be more hazardous or shifts the toxicity burden to others. To minimize the incidents of regrettable substitutions, BizNGO describes "Common Principles" to frame a process for informed substitution. Two of these 6 principles are: "reduce hazard" and "minimize exposure." A number of frameworks have emerged to evaluate and assess alternatives. One framework developed by leading experts under the auspices of the US National Academy of Sciences recommended that hazard and exposure be specifically addressed in the same step when assessing candidate alternatives. For the alternative assessment community, this article serves as an informational resource for considering exposure in an alternatives assessment using elements of problem formulation; product identity, use, and composition; hazard analysis; exposure analysis; and risk characterization. These conceptual elements build on practices from government, academia, and industry and are exemplified through 2 hypothetical case studies demonstrating the questions asked and decisions faced in new product development. These 2 case studies-inhalation exposure to a generic paint product and environmental exposure to a shampoo rinsed down the drain-demonstrate the criteria, considerations, and methods required to combine exposure models addressing human health and environmental impacts to provide a screening level hazard and exposure (risk) analysis. This article informs practices for these elements within a comparative risk context

  16. Impact of exposure to low levels of mercury on the health of dental workers

    Directory of Open Access Journals (Sweden)

    Leda Freitas Jesus

    2016-09-01

    Full Text Available This work evaluated the impact of exposure to mercury on the health of workers comparing dentists and dental assistants exposed to mercury by handling amalgam in a public dental clinic with a reference group which, in private offices, did not make use of the metal in their professional routine. Data collection included mercury levels in urine and air samples determined by cold vapor atomic absorption spectrometry, questionnaires and direct observation. The difference between urine and air samples in both groups was statistically significant while mercury levels in air and urine showed positive associations. Mercury concentration in urine correlated with gender, practice time, and age of workers. Half of those exposed had complaints compatible with mercury contamination. Among the exposed, the most common complaints were cognitive and neurocognitive symptoms. Correlations between symptoms and exposure time and also number of amalgam fillings placed per week were positive. Amalgam handling resulted in environmental and biological contamination by mercury.

  17. Prenatal exposure to lead in Spain: cord blood levels and associated factors.

    Science.gov (United States)

    Llop, Sabrina; Aguinagalde, Xabier; Vioque, Jesus; Ibarluzea, Jesús; Guxens, Mònica; Casas, Maribel; Murcia, Mario; Ruiz, María; Amurrio, Ascensión; Rebagliato, Marisa; Marina, Loreto Santa; Fernandez-Somoano, Ana; Tardon, Adonina; Ballester, Ferran

    2011-05-01

    Lead is a known neurotoxic. Fetuses and infants are very vulnerable to lead exposure, since their blood-brain barrier is not completely formed. Hence, there is an importance for monitoring of blood lead levels prenatally and during early infancy. The aim of this study is to evaluate the prenatal exposure to lead and its association with maternal factors in four population based mother-child cohorts in Spain. The present research was carried out within the framework of the INMA project INfancia y Medio Ambiente (Environment and Childhood). A total of 1462 pregnant women were recruited between 2004 and 2008. Lead was analyzed in a sample of cord blood by thermal decomposition, amalgation, and Atomic Absorption Spectrometry. Maternal sociodemographic, lifestyle and dietary factors were obtained by questionnaires during pregnancy. A multivariate logistic regression model was constructed. The dependent variable was a dichotomous lead level variable (detected vs no detected, i.e. ≥ vs < 2μg/dL). A low percentage of cord blood samples with lead levels ≥ 2μg/dL were found (5.9%). Geometric mean and maximum were 1.06μg/dL and 19μg/dL, respectively. Smoking at the beginning of pregnancy, age, social class, weight gain during pregnancy, gravidity, and place of residence were the maternal factors associated with detectable cord blood lead levels. Mother's diet does not appear to be a determining factor of lead exposure. Nevertheless, daily intake of iron and zinc may act as a protective factor against having cord blood lead levels ≥ 2μg/dL. In the different regions of Spain taking part in this study, lead levels to which newborns are exposed are low. Mobilization of lead from bones may be the main contributor to the cord blood levels. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. The relationship between blood lead levels and occupational exposure in a pregnant population.

    Science.gov (United States)

    La-Llave-León, Osmel; Salas Pacheco, José Manuel; Estrada Martínez, Sergio; Esquivel Rodríguez, Eloísa; Castellanos Juárez, Francisco X; Sandoval Carrillo, Ada; Lechuga Quiñones, Angélica María; Vázquez Alanís, Fernando; García Vargas, Gonzalo; Méndez Hernández, Edna Madai; Duarte Sustaita, Jaime

    2016-12-07

    Pregnant women exposed to lead are at risk of suffering reproductive damages, such as miscarriage, preeclampsia, premature delivery and low birth weight. Despite that the workplace offers the greatest potential for lead exposure, there is relatively little information about occupational exposure to lead during pregnancy. This study aims to assess the association between blood lead levels and occupational exposure in pregnant women from Durango, Mexico. A cross-sectional study was carried out in a population of 299 pregnant women. Blood lead was measured in 31 women who worked in jobs where lead is used (exposed group) and 268 who did not work in those places (control group). Chi-square test was applied to compare exposed and control groups with regard to blood lead levels. Odds ratio (OR) and 95% confidence intervals (CI) were calculated. Multivariable regression analysis was applied to determine significant predictors of blood lead concentrations in the exposed group. Exposed women had higher blood lead levels than those in the control group (4.00 ± 4.08 μg/dL vs 2.65 ± 1.75 μg/dL, p = 0.002). Furthermore, women in the exposed group had 3.82 times higher probability of having blood lead levels ≥ 5 μg/dL than those in the control group. Wearing of special workwear, changing clothes after work, living near a painting store, printing office, junkyard or rubbish dump, and washing the workwear together with other clothes resulted as significant predictors of elevated blood lead levels in the exposed group. Pregnant working women may be at risk of lead poisoning because of occupational and environmental exposure. The risk increases if they do not improve the use of protective equipment and their personal hygiene.

  19. The relationship between blood lead levels and occupational exposure in a pregnant population

    Directory of Open Access Journals (Sweden)

    Osmel La-Llave-León

    2016-12-01

    Full Text Available Abstract Background Pregnant women exposed to lead are at risk of suffering reproductive damages, such as miscarriage, preeclampsia, premature delivery and low birth weight. Despite that the workplace offers the greatest potential for lead exposure, there is relatively little information about occupational exposure to lead during pregnancy. This study aims to assess the association between blood lead levels and occupational exposure in pregnant women from Durango, Mexico. Methods A cross-sectional study was carried out in a population of 299 pregnant women. Blood lead was measured in 31 women who worked in jobs where lead is used (exposed group and 268 who did not work in those places (control group. Chi-square test was applied to compare exposed and control groups with regard to blood lead levels. Odds ratio (OR and 95% confidence intervals (CI were calculated. Multivariable regression analysis was applied to determine significant predictors of blood lead concentrations in the exposed group. Results Exposed women had higher blood lead levels than those in the control group (4.00 ± 4.08 μg/dL vs 2.65 ± 1.75 μg/dL, p = 0.002. Furthermore, women in the exposed group had 3.82 times higher probability of having blood lead levels ≥ 5 μg/dL than those in the control group. Wearing of special workwear, changing clothes after work, living near a painting store, printing office, junkyard or rubbish dump, and washing the workwear together with other clothes resulted as significant predictors of elevated blood lead levels in the exposed group. Conclusions Pregnant working women may be at risk of lead poisoning because of occupational and environmental exposure. The risk increases if they do not improve the use of protective equipment and their personal hygiene.

  20. Repeated Exposure to Neurotoxic Levels of Chlorpyriphos Alters Hippocampal Expression of Neurotrophins and Neuropeptides

    Science.gov (United States)

    2016-01-13

    hormone bindi Bdnf BDNF Brain-derived neurotrophic factor Mdk MDK Midkine (neurite growth -promoting fa Rbp4 RBP4 Retinol binding protein 4, plasma...cause cholinergic crisis are associated with problems in cognitive function (i.e., learning and memory deficits ), but the biological mechanism(s...neurobehavioral deficits following subchronic exposure to CPF at a level that inhibits hippocampal cholinesterase to less than 20% of control. An equally

  1. Seasonal variations of radon and the radiation exposure levels in Nerja cave, Spain

    International Nuclear Information System (INIS)

    Duenas, C.; Fernandez, M.C.; Canete, S.; Perez, M.; Gordo, E.

    2011-01-01

    222 Rn concentrations in the air in Nerja cave (Spain) (3 o 52'35''W 36 o 43'50''N) were measured by continuous monitoring using Alpha-Guard, Genitron instrument equipment. The 222 Rn measurements were carried out for a complete annual cycle in the different halls: Vestibule hall from July 2003 to June 2004, Ballet hall from July 2004 to June 2005 and Mirador hall from July 2005 to June 2006. Starting from the entrance of the cave we successively find the Vestibule hall, the Ballet hall and the Mirador hall. The range of 222 Rn levels were of 8-627 Bq m -3 for the Vestibule hall, 28-575 Bq m -3 for the Ballet hall and 38-578 Bq m -3 for the Mirador. The aim of this study was to detect seasonal variation patterns of 222 Rn concentrations. The seasonal variations of 222 Rn concentrations are discussed in relation to various meteorological factors measured inside and outside the cave. The radiation exposure levels for workers and tourists with different equilibrium factors have been evaluated. The radiation exposure levels for workers and tourists only represent a low percentage of the exposure guides for the general population. - Highlights: → The aim of the study was to detect seasonal variation of 222 Rn concentrations. → 222 Rn concentrations in the air-cave were measured by continuous monitoring. → The 222 Rn measurements were carried out in the different halls of the cave. → The radiation exposure levels for workers and tourists have been evaluated.

  2. Occurrence of 210Po and Biological Effects of Low-Level Exposure: The Need for Research

    OpenAIRE

    Seiler, Ralph L.; Wiemels, Joseph L.

    2012-01-01

    Background: Polonium-210 (210Po) concentrations that exceed 1 Bq/L in drinking-water supplies have been reported from four widely separated U.S. states where exposure to it went unnoticed for decades. The radionuclide grandparents of 210Po are common in sediments, and segments of the public may be chronically exposed to low levels of 210Po in drinking water or in food products from animals raised in contaminated areas. Objectives: We summarized information on the environmental behavior, bioki...

  3. Modeling Human Exposure Levels to Airborne Volatile Organic Compounds by the Hebei Spirit Oil Spill

    OpenAIRE

    Kim, Jong Ho; Kwak, Byoung Kyu; Ha, Mina; Cheong, Hae-Kwan; Yi, Jongheop

    2012-01-01

    Objectives The goal was to model and quantify the atmospheric concentrations of volatile organic compounds (VOCs) as the result of the Hebei Spirit oil spill, and to predict whether the exposure levels were abnormally high or not. Methods We developed a model for calculating the airborne concentration of VOCs that are produced in an oil spill accident. The model was applied to a practical situation, namely the Hebei Spirit oil spill. The accuracy of the model was verified by comparing the res...

  4. Low-level lead exposure effects on spatial reference memory and working memory in rats

    Institute of Scientific and Technical Information of China (English)

    Xinhua Yang; Ping Zhou; Yonghui Li

    2009-01-01

    BACKGROUND: Studies have demonstrated that lead exposure can result in cognitive dysfunction and behavior disorders. However, lead exposure impairments vary under different experimental conditions.OBJECTIVE: To detect changes in spatial learning and memory following low-level lead exposure in rats, in Morris water maze test under the same experimental condition used to analyze lead exposure effects on various memory types and learning processes.DESIGN AND SETTING: The experiment was conducted at the Animal Laboratory, Institute of Psychology, Chinese Academy of Science between February 2005 and March 2006. One-way analysis of variance (ANOVA) and behavioral observations were performed.MATERIALS: Sixteen male, healthy, adult, Sprague Dawley rats were randomized into normal control and lead exposure groups (n = 8).METHODS: Rats in the normal control group were fed distilled water, and those in the lead exposure group were fed 250 mL of 0.05% lead acetate once per day. At day 28, all rats performed the Morris water maze test, consisting of four phases: space navigation, probe test, working memory test, and visual cue test.MAIN OUTCOME MEASURES: Place navigation in the Morris water maze was used to evaluate spatial learning and memory, probe trials for spatial reference memory, working memory test for spatial working memory, and visual cue test for non-spatial cognitive function. Perkin-Elmer Model 300 Atomic Absorption Spectrometer was utilized to determine blood lead levels in rats.RESULTS: (1) In the working memory test, the time to reach the platform remained unchanged between the control and lead exposure groups (F(1,1) = 0.007, P = 0.935). A visible decrease in escape latencies was observed in each group (P = 0.028). However, there was no significant difference between the two groups (F(1,1) = 1.869, P = 0.193). The working memory probe test demonstrated no change between the two groups in the time spent in the target quadrant during the working memory probe test

  5. Sound Visualisation

    OpenAIRE

    Dolenc, Peter

    2013-01-01

    This thesis contains a description of a construction of subwoofer case that has an extra functionality of being able to produce special visual effects and display visualizations that match the currently playing sound. For this reason, multiple lighting elements made out of LED (Light Emitting Diode) diodes were installed onto the subwoofer case. The lighting elements are controlled by dedicated software that was also developed. The software runs on STM32F4-Discovery evaluation board inside a ...

  6. Comparison of radiofrequency electromagnetic field exposure levels in different everyday microenvironments in an international context.

    Science.gov (United States)

    Sagar, Sanjay; Adem, Seid M; Struchen, Benjamin; Loughran, Sarah P; Brunjes, Michael E; Arangua, Lisa; Dalvie, Mohamed Aqiel; Croft, Rodney J; Jerrett, Michael; Moskowitz, Joel M; Kuo, Tony; Röösli, Martin

    2018-05-01

    The aim of this study was to quantify RF-EMF exposure applying a tested protocol of RF-EMF exposure measurements using portable devices with a high sampling rate in different microenvironments of Switzerland, Ethiopia, Nepal, South Africa, Australia and the United States of America. We used portable measurement devices for assessing RF-EMF exposure in 94 outdoor microenvironments and 18 public transport vehicles. The measurements were taken either by walking with a backpack with the devices at the height of the head and a distance of 20-30 cm from the body, or driving a car with the devices mounted on its roof, which was 170-180 cm above the ground. The measurements were taken for about 30 min while walking and about 15-20 min while driving in each microenvironment, with a sampling rate of once every 4 s (ExpoM-RF) and 5 s (EME Spy 201). Mean total RF-EMF exposure in various outdoor microenvironments varied between 0.23 V/m (non-central residential area in Switzerland) and 1.85 V/m (university area in Australia), and across modes of public transport between 0.32 V/m (bus in rural area in Switzerland) and 0.86 V/m (Auto rickshaw in urban area in Nepal). For most outdoor areas the major exposure contribution was from mobile phone base stations. Otherwise broadcasting was dominant. Uplink from mobile phone handsets was generally very small, except in Swiss trains and some Swiss buses. This study demonstrates high RF-EMF variability between the 94 selected microenvironments from all over the world. Exposure levels tended to increase with increasing urbanity. In most microenvironments downlink from mobile phone base stations is the most relevant contributor. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Effects of low-level sarin and cyclosarin exposure on hippocampal microstructure in Gulf War Veterans.

    Science.gov (United States)

    Chao, Linda L; Zhang, Yu

    2018-05-04

    In early March 1991, shortly after the end of the Gulf War (GW), a munitions dump was destroyed at Khamisiyah, Iraq. Later, in 1996, the dump was found to have contained the organophosphorus (OP) nerve agents sarin and cyclosarin. We previously reported evidence of smaller hippocampal volumes in GW veterans with predicted exposure to the Khamisiyah plume compared to unexposed GW veterans. To investigate whether these macroscopic hippocampal volume changes are accompanied by microstructural alterations in the hippocampus, the current study acquired diffusion-tensor imaging (DTI), T1-, and T2-weighted images from 170 GW veterans (mean age: 53 ± 7 years), 81 of whom had predicted exposure to the Khamisiyah plume according to Department of Defense (DOD) plume modeling. We examined fractional anisotropy (FA), mean diffusivity (MD), and grey matter (GM) density from a hippocampal region of interest (ROI). Results indicate that, even after accounting for total hippocampal GM density (or hippocampal volume), age, sex, apolipoprotein ε4 genotype, and potential confounding OP pesticide exposures, hippocampal MD significantly predicted Khamisiyah exposure status (model p = 0.005, R 2  = 0.215, standardized coefficient β = 0.26, t = 2.85). Hippocampal MD was also inversely correlated with verbal memory learning performance in the entire study sample (p = 0.001). There were no differences in hippocampal FA or GM density; however, veterans with predicted Khamisiyah exposure had smaller hippocampal volumes compared to unexposed veterans. Because MD is sensitive to general microstructural disruptions that lead to increased extracellular spaces due to neuronal death, inflammation and gliosis, and/or to axonal loss or demyelination, these findings suggest that low-level exposure to the Khamisiyah plume has a detrimental, lasting effects on both macro- and micro-structure of the hippocampus. Copyright © 2018. Published by Elsevier Inc.

  8. Effects of childhood trauma exposure and cortisol levels on cognitive functioning among breast cancer survivors.

    Science.gov (United States)

    Kamen, Charles; Scheiber, Caroline; Janelsins, Michelle; Jo, Booil; Shen, Hanyang; Palesh, Oxana

    2017-10-01

    Cognitive functioning difficultiesin breast cancer patients receiving chemotherapy are common, but not all women experience these impairments. Exposure to childhood trauma may impair cognitive functioning following chemotherapy, and these impairments may be mediated by dysregulation of hypothalamic-pituitary-adrenal (HPA) axis function and cortisol slope. This study evaluated the association between childhood trauma exposure, cortisol, and cognition in a sample of breast cancer survivors. 56 women completed measures of trauma exposure (the Traumatic Events Survey), salivary cortisol, and self-reported cognitive functioning (the Functional Assessment of Cancer Therapy - Cognitive). We examined correlations between childhood trauma exposure and cognitive functioning, then used linear regression to control for factors associated with cognition (age, education, time since chemotherapy, depression, anxiety, and insomnia), and the MacArthur approach to test whether cortisol levels mediated the relationship between trauma and cognitive functioning. 57.1% of the sample had experienced at least one traumatic event in childhood, with 19.6% of the sample witnessing a serious injury, 17.9% experiencing physical abuse, and 14.3% experiencing sexual abuse. Childhood trauma exposure and cognitive functioning were moderately associated (r=-0.29). This association remained even when controlling for other factors associated with cognition; the final model explained 47% of the variance in cognitive functioning. The association between childhood trauma and cognitive functioning was mediated by steeper cortisol slope (partial r=0.35, p=0.02). Childhood trauma exposure is associated with self-reported cognitive functioning among breast cancer survivors and is mediated by cortisol dysregulation. Trauma should be considered, among other factors, in programs aiming to address cognition in this population. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Levels and Determinants of DDT and DDE Exposure in the VHEMBE Cohort.

    Science.gov (United States)

    Gaspar, Fraser W; Chevrier, Jonathan; Quirós-Alcalá, Lesliam; Lipsitt, Jonah M; Barr, Dana Boyd; Holland, Nina; Bornman, Riana; Eskenazi, Brenda

    2017-07-07

    Although indoor residual spraying (IRS) is an effective tool for malaria control, its use contributes to high insecticide exposure in sprayed communities and raises concerns about possible unintended health effects. The Venda Health Examination of Mothers, Babies and their Environment (VHEMBE) is a birth cohort study initiated in 2012 to characterize prenatal exposure to IRS insecticides and exposures' impacts on child health and development in rural South Africa. In this report, we describe the VHEMBE cohort and dichlorodiphenyltrichloroethane (DDT) and dichlorodiphenyldichloroethylene (DDE) serum concentrations measured in VHEMBE mothers when they presented for delivery. In addition, we applied a causal inference framework to estimate the potential reduction in population-level p , p' -DDT and p , p' -DDE serum concentrations under five hypothetical interventions. A total of 751 mothers were enrolled. Serum concentrations of p , p' isomers of DDT and DDE were above the limit of detection (LOD) in ≥98% of the samples, whereas the o , p' isomers were above the LOD in at least 80% of the samples. Median (interquartile range) p , p' -DDT and p , p' -DDE serum concentrations for VHEMBE cohort participants were 55.3 (19.0-259.3) and 242.2 (91.8-878.7) ng/g-lipid, respectively. Mothers reporting to have lived in a home sprayed with DDT for malaria control had ~5-7 times higher p , p' -DDT and p , p' -DDE serum concentrations than those who never lived in a home sprayed with DDT. Of the five potential interventions tested, we found increasing access to water significantly reduced p , p' -DDT exposure and increasing the frequency of household wet mopping significantly reduced p , p' -DDT and p , p' -DDE exposure. Our findings suggest that several intervention approaches may reduce DDT/DDE exposure in pregnant women living in IRS communities. https://doi.org/10.1289/EHP353.

  10. Case-control study of congenital malformations and occupational exposure to low-level ionizing radiation

    International Nuclear Information System (INIS)

    Sever, L.E.; Gilbert, E.S.; Hessol, N.A.; McIntyre, J.M.

    1988-01-01

    In a case-control study, the authors investigated the association of parental occupational exposure to low-level external whole-body penetrating ionizing radiation and risk of congenital malformations in their offspring. Cases and controls were ascertained from births in two counties in southeastern Washington State, where the Hanford Site has been a major employer. A unique feature of this study was the linking of quantitative individual measurement of external whole-body penetrating ionizing radiation exposure of employees at the Hanford Site, using personal dosimeters, and the disease outcome, congenital malformations. The study population included 672 malformation cases and 977 matched controls from births occurring from 1957 through 1980. Twelve specific malformation types were analyzed for evidence of association with employment of the parents at Hanford and with occupational exposure to ionizing radiation. Two defects, congenital dislocation of the hip and tracheoesophageal fistula, showed statistically significant associations with employment of the parents at Hanford, but not with parental radiation exposure. Neural tube defects showed a significant association with parental preconception exposure, on the basis of a small number of cases. Eleven other defects, including Down syndrome, for which an association with radiation was considered most likely, showed no evidence of such an association. When all malformations were analyzed as a group, there was no evidence of an association with employment of the parents at Hanford, but the relation of parental exposure to radiation before conception was in the positive direction (one-tailed p value between 0.05 and 0.10). Given the number of statistical tests conducted, some or all of the observed positive correlations are likely to represent false positive findings. 30 references

  11. Sounding the warning bells: the need for a systems approach to understanding behaviour at rail level crossings.

    Science.gov (United States)

    Read, Gemma J M; Salmon, Paul M; Lenné, Michael G

    2013-09-01

    Collisions at rail level crossings are an international safety concern and have been the subject of considerable research effort. Modern human factors practice advocates a systems approach to investigating safety issues in complex systems. This paper describes the results of a structured review of the level crossing literature to determine the extent to which a systems approach has been applied. The measures used to determine if previous research was underpinned by a systems approach were: the type of analysis method utilised, the number of component relationships considered, the number of user groups considered, the number of system levels considered and the type of model described in the research. None of research reviewed was found to be consistent with a systems approach. It is recommended that further research utilise a systems approach to the study of the level crossing system to enable the identification of effective design improvements. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  12. Prenatal Earthquake Exposure and Midlife Uric Acid Levels Among Chinese Adults.

    Science.gov (United States)

    Ji, Chunpeng; Li, Yanping; Cui, Liufu; Cai, Jianfang; Shi, Jihong; Cheng, Feon W; Li, Yuqing; Curhan, Gary C; Wu, Shouling; Gao, Xiang

    2017-05-01

    To test whether prenatal exposure to earthquake (as a surrogate for acute prenatal stress) could have unfavorable effects on uric acid levels later in life. We included 536 individuals who had been prenatally exposed to the Tangshan earthquake in 1976, and 536 sex- and age-matched individuals without that exposure. Serum uric acid concentrations were measured based on fasting blood samples, which were repeatedly collected in 2006, 2008, and 2010. Mean uric acid concentrations in 2010 and the increasing rate from 2006 to 2010 were compared between the 2 groups, after adjustment for age, sex, body mass index, serum concentrations of glucose, triglycerides, C-reactive protein level, estimated glomerular filtration rate, and other potential confounders. We also used multiple logistic regression to estimate the risk of hyperuricemia (>416 μmole/liter in men or >357 μmole/liter in women) in 2010 by calculating the odds ratios (ORs) and 95% confidence intervals (95% CIs) after adjustment for the previously mentioned covariates. Participants with prenatal exposure to the earthquake had higher concentrations of serum uric acid (adjusted means 315 μmole/liter versus 296 μmole/liter; P = 0.001) and a higher likelihood of having hyperuricemia (multivariate adjusted OR 1.70 [95% CI 1.09-2.66]) in 2010 relative to those without the exposure. Prenatal exposure to the earthquake was consistently significantly associated with a faster increase in uric acid concentration from 2006 to 2010 (P earthquake was associated with higher serum uric acid and higher odds of hyperuricemia in early adulthood. © 2016, American College of Rheumatology.

  13. Global levels of histone modifications in peripheral blood mononuclear cells of subjects with exposure to nickel.

    Science.gov (United States)

    Arita, Adriana; Niu, Jingping; Qu, Qingshan; Zhao, Najuan; Ruan, Ye; Nadas, Arthur; Chervona, Yana; Wu, Fen; Sun, Hong; Hayes, Richard B; Costa, Max

    2012-02-01

    Occupational exposure to nickel (Ni) is associated with an increased risk for lung and nasal cancers. Ni compounds exhibit weak mutagenic activity, cause gene amplification, and disrupt cellular epigenetic homeostasis. However, the Ni-induced changes in global histone modification levels have only been tested in vitro. This study was conducted in a Chinese population to determine whether occupational exposure to Ni is associated with alterations of global histone modification levels and to evaluate the inter- and intraindividual variance of global histone modification levels. Forty-five subjects with occupational exposure to Ni and 75 referents were recruited. Urinary Ni and global H3K4 trimethylation, H3K9 acetylation, and H3K9 dimethylation levels were measured in peripheral blood mononuclear cells (PBMCs) of subjects. H3K4me3 was elevated in Ni-exposed subjects (0.25% ± 0.11%) compared with referents (0.15% ± 0.04%; p = 0.0004), and H3K9me2 was decreased (Ni-exposed subjects, 0.11% ± 0.05%; referents, 0.15% ± 0.04%; p = 0.003). H3K4me3 was positively (r = 0.4, p = 0.0008) and H3K9ac was negatively (r = 0.1, p = 0.01) associated with urinary Ni. Interindividual variances of H3K4me3, H3K9ac, and H3K9me2 were larger compared with intraindividual variance in both exposure test groups, resulting in reliability coefficients (an estimate of consistency of a set of measurements) of 0.60, 0.67, and 0.79 for H3K4me3, H3K9ac, and H3K9me2, respectively, for Ni-exposed subjects and of 0.75, 0.74, and 0.97, respectively, for referent subjects. The results of this study indicate that occupational exposure to Ni is associated with alterations of global histone modification levels and that measurements of global levels of histone modifications are relatively stable over time in human PBMCs.

  14. Sound for digital video

    CERN Document Server

    Holman, Tomlinson

    2013-01-01

    Achieve professional quality sound on a limited budget! Harness all new, Hollywood style audio techniques to bring your independent film and video productions to the next level.In Sound for Digital Video, Second Edition industry experts Tomlinson Holman and Arthur Baum give you the tools and knowledge to apply recent advances in audio capture, video recording, editing workflow, and mixing to your own film or video with stunning results. This fresh edition is chockfull of techniques, tricks, and workflow secrets that you can apply to your own projects from preproduction

  15. 1991 implementation of As Low As Reasonably Achievable (ALARA) administrative radiation exposure levels: Experiences and lessons learned

    International Nuclear Information System (INIS)

    Aldridge, T.L.; Baumann, B.L.

    1993-06-01

    As Low As Reasonably Achievable (ALARA) radiation exposure levels were implemented on January 1, 1991, by Westinghouse Hanford Company (WHC), a prime US Department of Energy (DOE) contractor, located in Richland, Washington. This paper describes the radiation exposure levels which were implemented and the associated experiences and lessons learned. The issue of a report from the Committee on Biological Effectiveness of Ionizing Radiation in 1989 prompted DOE to re-evaluate its position on radiation exposure limits and the resulting doses received by occupational radiation workers. DOE requested that all it's contractors determine the impacts to operations from reduced radiation exposure levels

  16. Low-level arsenic exposure via drinking water consumption and female fecundity - A preliminary investigation.

    Science.gov (United States)

    Susko, Michele L; Bloom, Michael S; Neamtiu, Iulia A; Appleton, Allison A; Surdu, Simona; Pop, Cristian; Fitzgerald, Edward F; Anastasiu, Doru; Gurzau, Eugen S

    2017-04-01

    High level arsenic exposure is associated with reproductive toxicity in experimental and observational studies; however, few data exist to assess risks at low levels. Even less data are available to evaluate the impact of low level arsenic exposure on human fecundity. Our aim in this pilot study was a preliminary evaluation of associations between low level drinking water arsenic contamination and female fecundity. This retrospective study was conducted among women previously recruited to a hospital-based case-control study of spontaneous pregnancy loss in Timiṣ County, Romania. Women (n=94) with planned pregnancies of 5-20 weeks gestation completed a comprehensive physician-administered study questionnaire and reported the number of menstrual cycles attempting to conceive as the time to pregnancy (TTP). Drinking water samples were collected from residential drinking water sources and we determined arsenic levels using hydride generation-atomic absorption spectrometry (HG-AAS). Multivariable Cox-proportional hazards regression with Efron approximation was employed to evaluate TTP as a function of drinking water arsenic concentrations among planned pregnancies, adjusted for covariates. There was no main effect for drinking water arsenic exposure, yet the conditional probability for pregnancy was modestly lower among arsenic exposed women with longer TTPs, relative to women with shorter TTPs, and relative to unexposed women. For example, 1µg/L average drinking water arsenic conferred 5%, 8%, and 10% lower likelihoods for pregnancy in the 6th, 9th, and 12th cycles, respectively (P=0.01). While preliminary, our results suggest that low level arsenic contamination in residential drinking water sources may further impair fecundity among women with longer waiting times; however, this hypothesis requires confirmation by a future, more definitive study. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Effects of dietary lead exposure on vitamin levels in great tit nestlings – An experimental manipulation

    International Nuclear Information System (INIS)

    Ruiz, Sandra; Espín, Silvia; Rainio, Miia; Ruuskanen, Suvi; Salminen, Juha-Pekka; Lilley, Thomas M.; Eeva, Tapio

    2016-01-01

    Exposure to metal pollution negatively affects animal physiology, including nutrient metabolism, but in the wild an effect can seldom be attributed to a single metal. Moreover, little is known about how the metabolism of vitamins, essential micronutrients for developing juveniles, is affected by toxic metals. Therefore we experimentally investigated the effects of lead (Pb), a widespread toxic metal, on four fat-soluble vitamins A (total and retinol), D 3 , E (total and α-tocopherol) and K and carotenoids (lutein, zeaxanthin and unidentified) in great tit (Parus major) nestlings. In addition to a control group where no Pb was provided, two Pb-dosed groups were compared to a metal exposed group in the vicinity of a Ni–Cu smelter. We examined whether Pb treatment affects vitamin homeostasis and how the response of Pb-treated birds relates to that of a population under industrial exposure of Pb and other metals. For this purpose, vitamin and carotenoid levels were quantified with UPLC-MS from plasma of 7 days-old nestlings. All metal exposed groups showed increased vitamin A and retinol levels. However, vitamin levels were not directly associated with fecal Pb levels, with the exception of retinol, which was positively correlated with fecal Pb. Alpha-tocopherol, lutein and zeaxanthin levels were positively associated with body mass and wing growth rate. To conclude, Pb exposure increased plasma vitamin A and retinol levels while the levels of other vitamins and carotenoids rather reflected secondary pollution effects via differences in habitat and diet quality at the smelter site. Our findings suggest Pb exposed nestlings may allocate the vitamins needed for growth and development to fight the physiological stress thus compromising their fitness. - Highlights: • Pb effects on vitamins A, D 3 , E and K in wild great tit nestlings were investigated. • Four treatment groups were established: Control, Low-Pb, High-Pb and Smelter. • Pb concentrations measured in

  18. Pyrethroid insecticide exposure and reproductive hormone levels in healthy Japanese male subjects

    DEFF Research Database (Denmark)

    Yoshinaga, J; Imai, K; Shiraishi, H

    2014-01-01

    )] were explored in 322 male university students in suburban Tokyo. The subjects constituted part of a large cross-sectional survey on the reference value of semen quality of Japanese men. Urinary 3-PBA was detectable in 91% of the subjects demonstrating ubiquitous exposure among the general population....... However, there were no associations between urinary 3-PBA and serum hormone levels. This result was inconsistent with those reported in China and the USA for subjects who had similar levels of urinary 3-PBA to the present subjects. One of the possible reasons of the inconsistency might be different...

  19. Current practices for maintaining occupational exposures ALARA at low-level waste disposal sites

    International Nuclear Information System (INIS)

    Hadlock, D.E.; Herrington, W.N.; Hooker, C.D.; Murphy, D.W.; Gilchrist, R.L.

    1983-12-01

    The United States Nuclear Regulatory Commission contracted with Pacific Northwest Laboratory (PNL) to provide technical assistance in establishing operational guidelines, with respect to radiation control programs and methods of minimizing occupational radiation exposure, at Low-Level Waste (LLW) disposal sites. The PNL, through site visits, evaluated operations at LLW disposal sites to determine the adequacy of current practices in maintaining occupational exposures as low as is reasonably achievable (ALARA). The data sought included the specifics of: ALARA programs, training programs, external exposure control, internal exposure control, respiratory protection, surveillance, radioactive waste management, facilities and equipment, and external dose analysis. The results of the study indicated the following: The Radiation Protection and ALARA programs at the three commercial LLW disposal sites were observed to be adequate in scope and content compared to similar programs at other types of nuclear facilities. However, it should be noted that there were many areas that could be improved upon to help ensure the health and safety of occupationally exposed individuals

  20. Current practices for maintaining occupational exposures ALARA at low-level waste disposal sites

    Energy Technology Data Exchange (ETDEWEB)

    Hadlock, D.E.; Herrington, W.N.; Hooker, C.D.; Murphy, D.W.; Gilchrist, R.L.

    1983-12-01

    The United States Nuclear Regulatory Commission contracted with Pacific Northwest Laboratory (PNL) to provide technical assistance in establishing operational guidelines, with respect to radiation control programs and methods of minimizing occupational radiation exposure, at Low-Level Waste (LLW) disposal sites. The PNL, through site visits, evaluated operations at LLW disposal sites to determine the adequacy of current practices in maintaining occupational exposures as low as is reasonably achievable (ALARA). The data sought included the specifics of: ALARA programs, training programs, external exposure control, internal exposure control, respiratory protection, surveillance, radioactive waste management, facilities and equipment, and external dose analysis. The results of the study indicated the following: The Radiation Protection and ALARA programs at the three commercial LLW disposal sites were observed to be adequate in scope and content compared to similar programs at other types of nuclear facilities. However, it should be noted that there were many areas that could be improved upon to help ensure the health and safety of occupationally exposed individuals.

  1. Spatial avoidance to experimental increase of intermittent and continuous sound in two captive harbour porpoises.

    Science.gov (United States)

    Kok, Annebelle C M; Engelberts, J Pamela; Kastelein, Ronald A; Helder-Hoek, Lean; Van de Voorde, Shirley; Visser, Fleur; Slabbekoorn, Hans

    2018-02-01

    The continuing rise in underwater sound levels in the oceans leads to disturbance of marine life. It is thought that one of the main impacts of sound exposure is the alteration of foraging behaviour of marine species, for example by deterring animals from a prey location, or by distracting them while they are trying to catch prey. So far, only limited knowledge is available on both mechanisms in the same species. The harbour porpoise (Phocoena phocoena) is a relatively small marine mammal that could quickly suffer fitness consequences from a reduction of foraging success. To investigate effects of anthropogenic sound on their foraging efficiency, we tested whether experimentally elevated sound levels would deter two captive harbour porpoises from a noisy pool into a quiet pool (Experiment 1) and reduce their prey-search performance, measured as prey-search time in the noisy pool (Experiment 2). Furthermore, we tested the influence of the temporal structure and amplitude of the sound on the avoidance response of both animals. Both individuals avoided the pool with elevated sound levels, but they did not show a change in search time for prey when trying to find a fish hidden in one of three cages. The combination of temporal structure and SPL caused variable patterns. When the sound was intermittent, increased SPL caused increased avoidance times. When the sound was continuous, avoidance was equal for all SPLs above a threshold of 100 dB re 1 μPa. Hence, we found no evidence for an effect of sound exposure on search efficiency, but sounds of different temporal patterns did cause spatial avoidance with distinct dose-response patterns. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Chronic corticosterone exposure reduces hippocampal glycogen level and induces depression-like behavior in mice.

    Science.gov (United States)

    Zhang, Hui-yu; Zhao, Yu-nan; Wang, Zhong-li; Huang, Yu-fang

    2015-01-01

    Long-term exposure to stress or high glucocorticoid levels leads to depression-like behavior in rodents; however, the cause remains unknown. Increasing evidence shows that astrocytes, the most abundant cells in the central nervous system (CNS), are important to the nervous system. Astrocytes nourish and protect the neurons, and serve as glycogen repositories for the brain. The metabolic process of glycogen, which is closely linked to neuronal activity, can supply sufficient energy substrates for neurons. The research team probed into the effects of chronic corticosterone (CORT) exposure on the glycogen level of astrocytes in the hippocampal tissues of male C57BL/6N mice in this study. The results showed that chronic CORT injection reduced hippocampal neurofilament light protein (NF-L) and synaptophysin (SYP) levels, induced depression-like behavior in male mice, reduced hippocampal glycogen level and glycogen synthase activity, and increased glycogen phosphorylase activity. The results suggested that the reduction of the hippocampal glycogen level may be the mechanism by which chronic CORT treatment damages hippocampal neurons and induces depression-like behavior in male mice.

  3. Temporal and Spatial Variation in, and Population Exposure to, Summertime Ground-Level Ozone in Beijing.

    Science.gov (United States)

    Zhao, Hui; Zheng, Youfei; Li, Ting; Wei, Li; Guan, Qing

    2018-03-29

    Ground-level ozone pollution in Beijing has been causing concern among the public due to the risks posed to human health. This study analyzed the temporal and spatial distribution of, and investigated population exposure to, ground-level ozone. We analyzed hourly ground-level ozone data from 35 ambient air quality monitoring sites, including urban, suburban, background, and traffic monitoring sites, during the summer in Beijing from 2014 to 2017. The results showed that the four-year mean ozone concentrations for urban, suburban, background, and traffic monitoring sites were 95.1, 99.8, 95.9, and 74.2 μg/m³, respectively. A total of 44, 43, 45, and 43 days exceeded the Chinese National Ambient Air Quality Standards (NAAQS) threshold for ground-level ozone in 2014, 2015, 2016, and 2017, respectively. The mean ozone concentration was higher in suburban sites than in urban sites, and the traffic monitoring sites had the lowest concentration. The diurnal variation in ground-level ozone concentration at the four types of monitoring sites displayed a single-peak curve. The peak and valley values occurred at 3:00-4:00 p.m. and 7:00 a.m., respectively. Spatially, ground-level ozone concentrations decreased in gradient from the north to the south. Population exposure levels were calculated based on ground-level ozone concentrations and population data. Approximately 50.38%, 44.85%, and 48.49% of the total population of Beijing were exposed to ground-level ozone concentrations exceeding the Chinese NAAQS threshold in 2014, 2015, and 2016, respectively.

  4. Temporal and Spatial Variation in, and Population Exposure to, Summertime Ground-Level Ozone in Beijing

    Science.gov (United States)

    Zheng, Youfei; Li, Ting; Wei, Li; Guan, Qing

    2018-01-01

    Ground-level ozone pollution in Beijing has been causing concern among the public due to the risks posed to human health. This study analyzed the temporal and spatial distribution of, and investigated population exposure to, ground-level ozone. We analyzed hourly ground-level ozone data from 35 ambient air quality monitoring sites, including urban, suburban, background, and traffic monitoring sites, during the summer in Beijing from 2014 to 2017. The results showed that the four-year mean ozone concentrations for urban, suburban, background, and traffic monitoring sites were 95.1, 99.8, 95.9, and 74.2 μg/m3, respectively. A total of 44, 43, 45, and 43 days exceeded the Chinese National Ambient Air Quality Standards (NAAQS) threshold for ground-level ozone in 2014, 2015, 2016, and 2017, respectively. The mean ozone concentration was higher in suburban sites than in urban sites, and the traffic monitoring sites had the lowest concentration. The diurnal variation in ground-level ozone concentration at the four types of monitoring sites displayed a single-peak curve. The peak and valley values occurred at 3:00–4:00 p.m. and 7:00 a.m., respectively. Spatially, ground-level ozone concentrations decreased in gradient from the north to the south. Population exposure levels were calculated based on ground-level ozone concentrations and population data. Approximately 50.38%, 44.85%, and 48.49% of the total population of Beijing were exposed to ground-level ozone concentrations exceeding the Chinese NAAQS threshold in 2014, 2015, and 2016, respectively. PMID:29596366

  5. Temporal and Spatial Variation in, and Population Exposure to, Summertime Ground-Level Ozone in Beijing

    Directory of Open Access Journals (Sweden)

    Hui Zhao

    2018-03-01

    Full Text Available Ground-level ozone pollution in Beijing has been causing concern among the public due to the risks posed to human health. This study analyzed the temporal and spatial distribution of, and investigated population exposure to, ground-level ozone. We analyzed hourly ground-level ozone data from 35 ambient air quality monitoring sites, including urban, suburban, background, and traffic monitoring sites, during the summer in Beijing from 2014 to 2017. The results showed that the four-year mean ozone concentrations for urban, suburban, background, and traffic monitoring sites were 95.1, 99.8, 95.9, and 74.2 μg/m3, respectively. A total of 44, 43, 45, and 43 days exceeded the Chinese National Ambient Air Quality Standards (NAAQS threshold for ground-level ozone in 2014, 2015, 2016, and 2017, respectively. The mean ozone concentration was higher in suburban sites than in urban sites, and the traffic monitoring sites had the lowest concentration. The diurnal variation in ground-level ozone concentration at the four types of monitoring sites displayed a single-peak curve. The peak and valley values occurred at 3:00–4:00 p.m. and 7:00 a.m., respectively. Spatially, ground-level ozone concentrations decreased in gradient from the north to the south. Population exposure levels were calculated based on ground-level ozone concentrations and population data. Approximately 50.38%, 44.85%, and 48.49% of the total population of Beijing were exposed to ground-level ozone concentrations exceeding the Chinese NAAQS threshold in 2014, 2015, and 2016, respectively.

  6. THE EFFECTS ON LEARNING FROM A MOTION PICTURE FILM OF SELECTIVE CHANGES IN SOUND TRACK LOUDNESS LEVEL. FINAL REPORT.

    Science.gov (United States)

    MOAKLEY, FRANCIS X.

    EFFECTS OF PERIODIC VARIATIONS IN AN INSTRUCTIONAL FILM'S NORMAL LOUDNESS LEVEL FOR RELEVANT AND IRRELEVANT FILM SEQUENCES WERE MEASURED BY A MULTIPLE CHOICE TEST. RIGOROUS PILOT STUDIES, RANDOM GROUPING OF SEVENTH GRADERS FOR TREATMENTS, AND RATINGS OF RELEVANT AND IRRELEVANT PORTIONS OF THE FILM BY AN UNSPECIFIED NUMBER OF JUDGES PRECEDED THE…

  7. Estimation of directivity and sound power levels emitted by aircrafts during taxiing, for outdoor noise prediction purpose

    NARCIS (Netherlands)

    Asensio, C.; Pavón, I.; Ruiz, M.; Pagan Munoz, Raul; Recuero, M.

    2007-01-01

    Integrated noise model (INM) is the most internationally used software to calculate noise levels near airports. Take off, landing or pass by operations can be modeled by INM, but it does not consider aircrafts taxiing, which, in some cases, can be important to accurately evaluate and reduce

  8. Estimation of quantitative levels of diesel exhaust exposure and the health impact in the contemporary Australian mining industry

    NARCIS (Netherlands)

    Peters, Susan; de Klerk, Nicholas; Reid, Alison; Fritschi, Lin; Musk, Aw Bill; Vermeulen, Roel

    2017-01-01

    OBJECTIVES: To estimate quantitative levels of exposure to diesel exhaust expressed by elemental carbon (EC) in the contemporary mining industry and to describe the excess risk of lung cancer that may result from those levels. METHODS: EC exposure has been monitored in Western Australian miners

  9. Company-level, semi-quantitative assessment of occupational styrene exposure when individual data are not available.

    Science.gov (United States)

    Kolstad, Henrik A; Sønderskov, Jette; Burstyn, Igor

    2005-03-01

    In epidemiological research, self-reported information about determinants and levels of occupational exposures is difficult to obtain, especially if the disease under study has a high mortality rate or follow-up has exceeded several years. In this paper, we present a semi-quantitative exposure assessment strategy for nested case-control studies of styrene exposure among workers of the Danish reinforced plastics industry when no information on job title, task or other indicators of individual exposure were readily available from cases and controls. The strategy takes advantage of the variability in styrene exposure level and styrene exposure probability across companies. The study comprised 1522 cases of selected malignancies and neurodegenerative diseases and controls employed in 230 reinforced plastics companies and other related industries. Between 1960 and 1996, 3057 measurements of styrene exposure level obtained from 191 companies, were identified. Mixed effects models were used to estimate expected styrene exposure levels by production characteristics for all companies. Styrene exposure probability within each company was estimated for all but three cases and controls from the fraction of laminators, which was reported by a sample of 945 living colleagues of the cases and controls and by employers and dealers of plastic raw materials. The estimates were validated from a subset of 427 living cases and controls that reported their own work as laminators in the industry. We computed styrene exposure scores that integrated estimated styrene exposure level and styrene exposure probability. Product (boats), process (hand and spray lamination) and calendar year period were the major determinants of styrene exposure level. Within-company styrene exposure variability increased by calendar year and was accounted for when computing the styrene exposure scores. Exposure probability estimates based on colleagues' reports showed the highest predictive values in the

  10. Association of hypothyroidism with low-level arsenic exposure in rural West Texas

    International Nuclear Information System (INIS)

    Gong, Gordon; Basom, Janet; Mattevada, Sravan; Onger, Frederick

    2015-01-01

    It has been reported recently that a higher airborne arsenic level was correlated with higher urinary arsenic concentration and lower serum thyroxin level among urban policemen and rural highway workmen in Italy. The current study was to determine whether exposure to low-level arsenic groundwater (2–22 µg/L) is associated with hypothyroidism among 723 participants (118 male and 267 female Hispanics; 108 male and 230 female non-Hispanic whites, NHW) living in rural West Texas counties. Arsenic and iodine levels in their groundwater used for drinking and or cooking were estimated by the inverse distance weighted (IDW) interpolation technique. Groundwater arsenic was ≥8 µg/L in 36% of the subjects' wells while iodine concentration was <1 µg/L in 91% of their wells. Logistic regression analysis showed that arsenic in groundwater ≥8 µg/L and cumulative arsenic exposure (groundwater arsenic concentration multiplied by the number of years living in the current address) but not groundwater iodine concentration were significant predictors for hypothyroidism among Hispanics (p<0.05) but not NHW after adjusting for covariates such as age, gender, annual household income and health insurance coverage. The ethnic difference may be due to a marginally higher percentage of Hispanics (p=0.0622) who lived in areas with groundwater arsenic ≥8 µg/L compared with NHW. The prevalence of hypothyroidism was significantly higher in Hispanics or NHW of this rural cohort than the national prevalence. Measures should be taken to reduce arsenic in drinking water in order to prevent hypothyroidism in rural areas. - Highlights: • We determined if arsenic exposure is associated with hypothyroidism in rural Texas. • Groundwater arsenic level is associated with hypothyroidism among Hispanics only. • The rate of hypothyroidism in rural Texas was higher than the US general population

  11. Association of hypothyroidism with low-level arsenic exposure in rural West Texas

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Gordon, E-mail: gordon.gong@ttuhsc.edu [F. Marie Hall Institute for Rural and Community Health, Texas Tech University Health Sciences Center, Lubbock, TX (United States); Basom, Janet [F. Marie Hall Institute for Rural and Community Health, Texas Tech University Health Sciences Center, Lubbock, TX (United States); Department of Family and Community Medicine, Texas Tech University Health Sciences Center, Lubbock, TX (United States); Mattevada, Sravan [Department of Internal Medicine, University of North Texas Health Science Center, Fort Worth, TX (United States); Onger, Frederick [Department of Family and Community Medicine, Texas Tech University Health Sciences Center, Lubbock, TX (United States)

    2015-04-15

    It has been reported recently that a higher airborne arsenic level was correlated with higher urinary arsenic concentration and lower serum thyroxin level among urban policemen and rural highway workmen in Italy. The current study was to determine whether exposure to low-level arsenic groundwater (2–22 µg/L) is associated with hypothyroidism among 723 participants (118 male and 267 female Hispanics; 108 male and 230 female non-Hispanic whites, NHW) living in rural West Texas counties. Arsenic and iodine levels in their groundwater used for drinking and or cooking were estimated by the inverse distance weighted (IDW) interpolation technique. Groundwater arsenic was ≥8 µg/L in 36% of the subjects' wells while iodine concentration was <1 µg/L in 91% of their wells. Logistic regression analysis showed that arsenic in groundwater ≥8 µg/L and cumulative arsenic exposure (groundwater arsenic concentration multiplied by the number of years living in the current address) but not groundwater iodine concentration were significant predictors for hypothyroidism among Hispanics (p<0.05) but not NHW after adjusting for covariates such as age, gender, annual household income and health insurance coverage. The ethnic difference may be due to a marginally higher percentage of Hispanics (p=0.0622) who lived in areas with groundwater arsenic ≥8 µg/L compared with NHW. The prevalence of hypothyroidism was significantly higher in Hispanics or NHW of this rural cohort than the national prevalence. Measures should be taken to reduce arsenic in drinking water in order to prevent hypothyroidism in rural areas. - Highlights: • We determined if arsenic exposure is associated with hypothyroidism in rural Texas. • Groundwater arsenic level is associated with hypothyroidism among Hispanics only. • The rate of hypothyroidism in rural Texas was higher than the US general population.

  12. Prenatal exposure to lead in Spain: Cord blood levels and associated factors

    Energy Technology Data Exchange (ETDEWEB)

    Llop, Sabrina, E-mail: llop_sab@gva.es [Centre of Public Health Research (CSISP), Av Catalunya 21, 46020, Valencia (Spain); Carlos III Health Institute (ISCIII), 20220 Majadahonda, Madrid (Spain); CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Aguinagalde, Xabier [Public Health Laboratory of Alava, Direccion de Salud Publica, Gobierno Vasco, Santiago 11, 01002, Vitoria-Gasteiz, Basque Country (Spain); Vioque, Jesus [CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Universidad Miguel Hernandez, Av de Alicante KM 87, 03550, Sant Joan d' Alacant (Spain); Ibarluzea, Jesus [CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Departamento de Sanidad Gobierno Vasco, Subdireccion de Salud Publica de Gipuzkoa, Avenida de Navarra 4, 20013 San Sebastian (Spain); Biodonostia, Instituto de Investigacion Biomedica, San Sebastian (Spain); Guxens, Monica [CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Centre for Research of Environmental Epidemiology (CREAL), Doctor Aiguader 88, 8003 Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Doctor Aiguader 88, 8003 Barcelona (Spain); Casas, Maribel [Centre for Research of Environmental Epidemiology (CREAL), Doctor Aiguader 88, 8003 Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Doctor Aiguader 88, 8003 Barcelona (Spain); Murcia, Mario [Centre of Public Health Research (CSISP), Av Catalunya 21, 46020, Valencia (Spain); CIBER de Epidemiologia y Salud Publica (CIBERESP), Doctor Aiguader 88, 8003 Barcelona (Spain); Ruiz, Maria [Centre for Research of Environmental Epidemiology (CREAL), Doctor Aiguader 88, 8003 Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Doctor Aiguader 88, 8003 Barcelona (Spain); and others

    2011-05-01

    Introduction and Objective: Lead is a known neurotoxic. Fetuses and infants are very vulnerable to lead exposure, since their blood-brain barrier is not completely formed. Hence, there is an importance for monitoring of blood lead levels prenatally and during early infancy. The aim of this study is to evaluate the prenatal exposure to lead and its association with maternal factors in four population based mother-child cohorts in Spain. The present research was carried out within the framework of the INMA project INfancia y Medio Ambiente (Environment and Childhood). Methods: A total of 1462 pregnant women were recruited between 2004 and 2008. Lead was analyzed in a sample of cord blood by thermal decomposition, amalgation, and Atomic Absorption Spectrometry. Maternal sociodemographic, lifestyle and dietary factors were obtained by questionnaires during pregnancy. A multivariate logistic regression model was constructed. The dependent variable was a dichotomous lead level variable (detected vs no detected, i.e. {>=} vs < 2 {mu}g/dL). Results: A low percentage of cord blood samples with lead levels {>=} 2 {mu}g/dL were found (5.9%). Geometric mean and maximum were 1.06 {mu}g/dL and 19 {mu}g/dL, respectively. Smoking at the beginning of pregnancy, age, social class, weight gain during pregnancy, gravidity, and place of residence were the maternal factors associated with detectable cord blood lead levels. Mother's diet does not appear to be a determining factor of lead exposure. Nevertheless, daily intake of iron and zinc may act as a protective factor against having cord blood lead levels {>=} 2 {mu}g/dL. Conclusion: In the different regions of Spain taking part in this study, lead levels to which newborns are exposed are low. Mobilization of lead from bones may be the main contributor to the cord blood levels. - Research Highlights: {yields} Pb is a ubiquitous environmental pollutant with harmful effects on neurodevelopment. {yields} Cord blood Pb levels in

  13. Prenatal exposure to lead in Spain: Cord blood levels and associated factors

    International Nuclear Information System (INIS)

    Llop, Sabrina; Aguinagalde, Xabier; Vioque, Jesus; Ibarluzea, Jesus; Guxens, Monica; Casas, Maribel; Murcia, Mario; Ruiz, Maria

    2011-01-01

    Introduction and Objective: Lead is a known neurotoxic. Fetuses and infants are very vulnerable to lead exposure, since their blood-brain barrier is not completely formed. Hence, there is an importance for monitoring of blood lead levels prenatally and during early infancy. The aim of this study is to evaluate the prenatal exposure to lead and its association with maternal factors in four population based mother-child cohorts in Spain. The present research was carried out within the framework of the INMA project INfancia y Medio Ambiente (Environment and Childhood). Methods: A total of 1462 pregnant women were recruited between 2004 and 2008. Lead was analyzed in a sample of cord blood by thermal decomposition, amalgation, and Atomic Absorption Spectrometry. Maternal sociodemographic, lifestyle and dietary factors were obtained by questionnaires during pregnancy. A multivariate logistic regression model was constructed. The dependent variable was a dichotomous lead level variable (detected vs no detected, i.e. ≥ vs < 2 μg/dL). Results: A low percentage of cord blood samples with lead levels ≥ 2 μg/dL were found (5.9%). Geometric mean and maximum were 1.06 μg/dL and 19 μg/dL, respectively. Smoking at the beginning of pregnancy, age, social class, weight gain during pregnancy, gravidity, and place of residence were the maternal factors associated with detectable cord blood lead levels. Mother's diet does not appear to be a determining factor of lead exposure. Nevertheless, daily intake of iron and zinc may act as a protective factor against having cord blood lead levels ≥ 2 μg/dL. Conclusion: In the different regions of Spain taking part in this study, lead levels to which newborns are exposed are low. Mobilization of lead from bones may be the main contributor to the cord blood levels. - Research Highlights: → Pb is a ubiquitous environmental pollutant with harmful effects on neurodevelopment. → Cord blood Pb levels in Spanish newborn are low in

  14. Radiation exposure in the young level 1 trauma patient: a retrospective review.

    Science.gov (United States)

    Gottschalk, Michael B; Bellaire, Laura L; Moore, Thomas

    2015-01-01

    Computed tomography (CT) has become an increasingly popular and powerful tool for clinicians managing trauma patients with life-threatening injuries, but the ramifications of increasing radiation burden on individual patients are not insignificant. This study examines a continuous series of 337 patients less than 40 years old admitted to a level 1 trauma center during a 4-month period. Primary outcome measures included number of scans; effective dose of radiation from radiographs and CT scans, respectively; and total effective dose from both sources over patients' hospital stays. Several variables, including hospital length of stay, initial Glasgow Coma Scale score, and Injury Severity Score, correlated with greater radiation exposure. Blunt trauma victims were more prone to higher doses than those with penetrating or combined penetrating and blunt trauma. Location and mechanism of injury were also found to correlate with radiation exposure. Trauma patients as a group are exposed to high levels of radiation from X-rays and CT scans, and CT scans contribute a very high proportion (91.3% ± 11.7%) of that radiation. Certain subgroups of patients are at a particularly high risk of exposure, and greater attention to cumulative radiation dose should be paid to patients with the above mentioned risk factors.

  15. Monitoring of low level environmental gamma exposure by the centralized radiation monitoring system

    International Nuclear Information System (INIS)

    Katagiri, Hiroshi; Kobayashi, Hideo; Obata, Kazuichi; Kokubu, Morinobu; Itoh, Naoji

    1981-07-01

    In the Japan Atomic Energy Research Institute (JAERI), a centralized automatic radiation monitoring system developed 20 years ago has recently been improved to monitor low level gamma radiation more accurately in normal operation of the nuclear facilities and to detect abnormal radioactive releases more effectively. The present state of the system is described. This system puts together environmental monitoring data such as gamma exposure rate (20 points), radioactive concentration in the air (4 points) and in water (2 drains), and meteorological items (14 including wind directions, wind speeds, solar radiation and air temperatures at a observation tower of 40 m height). Environmental monitoring around the JAERI site is carried out effectively using the system. Data processing system consists of a central processing unit, a magnetic disk, a magnetic tape, a line printer and a console typewriter. The data at respective monitoring points are transmitted to the central monitoring room by wireless or telephone line. All data are printed out and field in magnetic disk and magnetic tape every 10 minutes. When the emergency levels are exceeded, however, the data are automatically output on a line printer every 2 minute. This system can distinguish very low gamma exposure due to gaseous effluents, about 1 mR/y, from the background. Even in monthly exposures, calculated values based on the data of release amount and meteorology are in good agreement with the measured ones. (author)

  16. Coastal vertebrate exposure to predicted habitat changes due to sea level rise

    Science.gov (United States)

    Hunter, Elizabeth A.; Nibbelink, Nathan P.; Alexander, Clark R.; Barrett, Kyle; Mengak, Lara F.; Guy, Rachel; Moore, Clinton; Cooper, Robert J.

    2015-01-01

    Sea level rise (SLR) may degrade habitat for coastal vertebrates in the Southeastern United States, but it is unclear which groups or species will be most exposed to habitat changes. We assessed 28 coastal Georgia vertebrate species for their exposure to potential habitat changes due to SLR using output from the Sea Level Affecting Marshes Model and information on the species’ fundamental niches. We assessed forecasted habitat change up to the year 2100 using three structural habitat metrics: total area, patch size, and habitat permanence. Almost all of the species (n = 24) experienced negative habitat changes due to SLR as measured by at least one of the metrics. Salt marsh and ocean beach habitats experienced the most change (out of 16 categorical land cover types) across the three metrics and species that used salt marsh extensively (rails and marsh sparrows) were ranked highest for exposure to habitat changes. Species that nested on ocean beaches (Diamondback Terrapins, shorebirds, and terns) were also ranked highly, but their use of other foraging habitats reduced their overall exposure. Future studies on potential effects of SLR on vertebrates in southeastern coastal ecosystems should focus on the relative importance of different habitat types to these species’ foraging and nesting requirements. Our straightforward prioritization approach is applicable to other coastal systems and can provide insight to managers on which species to focus resources, what components of their habitats need to be protected, and which locations in the study area will provide habitat refuges in the face of SLR.

  17. Low level prenatal exposure to methylmercury disrupts neuronal migration in the developing rat cerebral cortex

    International Nuclear Information System (INIS)

    Guo, Bao-Qiang; Yan, Chong-Huai; Cai, Shi-Zhong; Yuan, Xiao-Bing; Shen, Xiao-Ming

    2013-01-01

    Highlights: ► Low level MeHg exposure causes migratory defect of rat cerebrocortical neurons. ► The migration defect is due to the impact of MeHg on the neuronal migration itself. ► Rho GTPases seem to be involved in MeHg-induced disruption of neuronal migration. -- Abstract: We determined the effects of low-level prenatal MeHg exposure on neuronal migration in the developing rat cerebral cortex using in utero electroporation. We used offspring rats born to dams that had been exposed to saline or various doses of MeHg (0.01 mg/kg/day, 0.1 mg/kg/day, and 1 mg/kg/day) from gestational day (GD) 11–21. Immunohistochemical examination of the brains of the offspring was conducted on postnatal day (PND) 0, PND3, and PND7. Our results showed that prenatal exposure to low levels of MeHg (0.1 mg/kg/day or 1 mg/kg/day) during the critical stage in neuronal migration resulted in migration defects of the cerebrocortical neurons in offspring rats. Importantly, our data revealed that the abnormal neuronal distribution induced by MeHg was not caused by altered proliferation of neural progenitor cells (NPCs), induction of apoptosis of NPCs and/or newborn neurons, abnormal differentiation of NPCs, and the morphological changes of radial glial scaffold, indicating that the defective neuronal positioning triggered by exposure to low-dose of MeHg is due to the impacts of MeHg on the process of neuronal migration itself. Moreover, we demonstrated that in utero exposure to low-level MeHg suppresses the expression of Rac1, Cdc42, and RhoA, which play key roles in the migration of cerebrocortical neurons during the early stage of brain development, suggesting that the MeHg-induced migratory disturbance of cerebrocortical neurons is likely associated with the Rho GTPases signal pathway. In conclusion, our results provide a novel perspective on clarifying the mechanisms underlying the impairment of neuronal migration induced by MeHg

  18. Photometrically measured continuous personal PM(2.5) exposure: levels and correlation to a gravimetric method.

    Science.gov (United States)

    Lanki, Timo; Alm, Sari; Ruuskanen, Juhani; Janssen, Nicole A H; Jantunen, Matti; Pekkanen, Juha

    2002-05-01

    There is evidence that hourly variations in exposure to airborne particulate matter (PM) may be associated with adverse health effects. Still there are only few published data on short-term levels of personal exposure to PM in community settings. The objectives of the study were to assess hourly and shorter-term variations in personal PM(2.5) exposure in Helsinki, Finland, and to compare results from portable photometers to simultaneously measured gravimetric concentrations. The effect of relative humidity on the photometric results was also evaluated. Personal PM(2.5) exposures of elderly persons were assessed for 24 h every second week, resulting in 308 successful measurements from 47 different subjects. Large changes in concentrations in minutes after cooking or changing microenvironment were seen. The median of daily 1-h maxima was over twice the median of 24-h averages. There was a strong significant association between the two means, which was not linear. Median (95th percentile) of the photometric 24-h concentrations was 12.1 (37.7) and of the 24-h gravimetric concentrations 9.2 (21.3) microg/m3. The correlation between the photometric and the gravimetric method was quite good (R2=0.86). Participants spent 94.1% of their time indoors or in a vehicle, where relative humidity is usually low and thus not likely to cause significant effects on photometric results. Even outdoors, the relative humidity had only modest effect on concentrations. Photometers are a promising method to explore the health effects of short-term variation in personal PM(2.5) exposure.

  19. Exposure to environmental levels of waterborne cadmium impacts corticosteroidogenic and metabolic capacities, and compromises secondary stressor performance in rainbow trout

    International Nuclear Information System (INIS)

    Sandhu, Navdeep; McGeer, James C.; Vijayan, Mathilakath M.

    2014-01-01

    Highlights: •Low level chronic waterborne cadmium exposure did not evoke a plasma cortisol response in rainbow trout. •Chronic cadmium exposure increases liver and gill metabolic capacities. •Chronic cadmium exposure disrupts head kidney steroidogenic capacity. •Chronic cadmium exposure disrupts glucocorticoid and mineralocorticoid receptor protein expressions in target tissues. •Chronic cadmium exposure compromises physiological performances to a secondary stressor in trout. -- Abstract: The physiological responses to waterborne cadmium exposure have been well documented; however, few studies have examined animal performances at low exposure concentrations of this metal. We tested the hypothesis that longer-term exposure to low levels of cadmium will compromise the steroidogenic and metabolic capacities, and reduce the cortisol response to a secondary stressor in fish. To test this, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to 0 (control), 0.75 or 2.0 μg/L waterborne cadmium in a flow-through system and were sampled at 1, 7 and 28 d of exposure. There were only very slight disturbances in basal plasma cortisol, lactate or glucose levels in response to cadmium exposure over the 28 d period. Chronic cadmium exposure significantly affected key genes involved in corticosteroidogenesis, including melanocortin 2 receptor, steroidogenic acute regulatory protein and cytochrome P450 side chain cleavage enzyme. At 28 d, the high cadmium exposure group showed a significant drop in the glucocorticoid receptor and mineralocorticoid receptor protein expressions in the liver and brain, respectively. There were also perturbations in the metabolic capacities in the liver and gill of cadmium-exposed trout. Subjecting these fish to a secondary handling disturbance led to a significant attenuation of the stressor-induced plasma cortisol, glucose and lactate levels in the cadmium groups. Collectively, although trout appears to adjust to subchronic exposure

  20. Exposure to environmental levels of waterborne cadmium impacts corticosteroidogenic and metabolic capacities, and compromises secondary stressor performance in rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Sandhu, Navdeep [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); McGeer, James C. [Department of Biology, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5 (Canada); Vijayan, Mathilakath M., E-mail: matt.vijayan@ucalgary.ca [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2014-01-15

    Highlights: •Low level chronic waterborne cadmium exposure did not evoke a plasma cortisol response in rainbow trout. •Chronic cadmium exposure increases liver and gill metabolic capacities. •Chronic cadmium exposure disrupts head kidney steroidogenic capacity. •Chronic cadmium exposure disrupts glucocorticoid and mineralocorticoid receptor protein expressions in target tissues. •Chronic cadmium exposure compromises physiological performances to a secondary stressor in trout. -- Abstract: The physiological responses to waterborne cadmium exposure have been well documented; however, few studies have examined animal performances at low exposure concentrations of this metal. We tested the hypothesis that longer-term exposure to low levels of cadmium will compromise the steroidogenic and metabolic capacities, and reduce the cortisol response to a secondary stressor in fish. To test this, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to 0 (control), 0.75 or 2.0 μg/L waterborne cadmium in a flow-through system and were sampled at 1, 7 and 28 d of exposure. There were only very slight disturbances in basal plasma cortisol, lactate or glucose levels in response to cadmium exposure over the 28 d period. Chronic cadmium exposure significantly affected key genes involved in corticosteroidogenesis, including melanocortin 2 receptor, steroidogenic acute regulatory protein and cytochrome P450 side chain cleavage enzyme. At 28 d, the high cadmium exposure group showed a significant drop in the glucocorticoid receptor and mineralocorticoid receptor protein expressions in the liver and brain, respectively. There were also perturbations in the metabolic capacities in the liver and gill of cadmium-exposed trout. Subjecting these fish to a secondary handling disturbance led to a significant attenuation of the stressor-induced plasma cortisol, glucose and lactate levels in the cadmium groups. Collectively, although trout appears to adjust to subchronic exposure

  1. Family environmental and dietary implications for low-level prenatal lead exposure in Wujiang City, China.

    Science.gov (United States)

    Yan, Jin; Gao, Zhenyan; Wang, Ju; Ma, Wenjuan; Ying, Xiaolan; Zhou, Cancan; Yan, Chonghuai

    2018-05-01

    To explore the potential environmental and dietary factors during pregnancy affecting low-level prenatal lead exposure, we conducted a longitudinal study in Wujiang City, China. A total of 1976 mother-infant pairs were included from 2009 to 2010. An interviewed questionnaire was conducted and cord blood samples were collected. The geometric means of cord blood lead level was 30.3 μg/L (95% CI, 29.8-30.8) with 99.24% below 100 μg/L. Maternal age, passive smoking, and living in the countryside were significantly associated with cord blood lead concentrations. Multiple logistic models showed that some family environmental factors including using firewood and electricity as kitchen fuel were positively correlated with increased cord blood lead levels. Among dietary sources recorded in this study, meat consumption (> 3 times/week), fish consumption (1-3 times/week), vegetables consumption (> 1 times/day), and fruit intake (> 1 times/day) had inverse relationship with cord blood lead levels. In general, our findings may have important implications for family environmental and dietary direction during pregnancy to decrease prenatal lead exposure.

  2. Assessment of correlation between leucocytes migration reaction and level of inhalation exposure to priority air contaminants

    Directory of Open Access Journals (Sweden)

    L.B. Masnavieva

    2017-09-01

    Full Text Available Nowadays each forth person suffers from allergic diseases and allergic pathology prevalence is constantly growing. There are compounds in air which are generally toxic, or have sensitizing or allergenic effects on a body. For example, we can name formaldehyde and nitrogen dioxide. Our research goal was to reveal a correlation between reaction of leucocytes migration inhibition to formaldehyde and level of inhalation exposure to the examined chemicals. We examined 410 teenag-ers who permanently lived in industrial cities in Irkutsk region. We studied individual load as per formaldehyde and nitrogen dioxide. We estimated eosinophils content in nasal mucus and determined indexes of leucocytes migration inhibition to for-maldehyde. Index of formaldehyde effects danger was detected to exceed 1 in 54% teenagers. The greatest value of danger coefficient in terms of exposure to this substance was equal to 1.76. anger index in terms of exposure to nitrogen dioxide didn't exceed 0.7 in the examined teenagers. The obtained results prove that inhalation formaldehyde load influences teenag-ers from industrial centers as sensitization to this substance evolves in them. We found out that true inhibition reaction of leucocytes migration in a reaction with formaldehyde more frequently occurred in people with danger index in terms of ex-posure to this substance being lower than 1. We obtained models which described correlation between level of sensitization to formaldehyde and a number of eosinophils in nasal mucus and it allowed us to detect that sensitization depended on the examined contaminants content in the air. The sensitization to chemical air contaminants which we revealed in teenagers calls for necessary activities aimed at reducing risks of allergenic pathology evolvement in them.

  3. Do hearing threshold levels in workers of the furniture industry reflect their exposure to noise?

    Directory of Open Access Journals (Sweden)

    Małgorzata Pawlaczyk-Łuszczyńska

    2016-06-01

    Full Text Available Background: The aim of the study was to analyze the hearing status of employees of a furniture factory with respect to their exposure to noise and the presence of additional risk factors of noise-induced hearing loss (NIHL. Material and Methods: Noise measurements, questionnaire survey and assessment of hearing, using pure tone audiometry, were carried out in 50 male workers, aged 20–57 years, directly employed in the manufacture of furniture. The actual workers’ hearing threshold levels (HTLs were compared with the predictions calculated according to PN-ISO 1999:2000 based on age, gender and noise exposure. Results: Workers under study were exposed to noise at daily noise exposure levels of 82.7–94.8 dB (mean: 90.9 dB for a period of 3–14 years. In all subjects, mean HTL at 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz did not exceed 25 dB. Nevertheless, high frequency notches were found in 11% of audiograms. The actual workers’ HTLs at 3000–6000 Hz were similar to those predicted using PN-ISO 1999:2000. There were statistical significant differences between HTLs in subgroups of people with higher (> 78 mm Hg and lower (≤ 78 mm Hg diastolic blood pressure, smokers and non-smokers, and those working with organic solvents. Hearing loss was more evident in subjects affected by the additional risk factors specified above. Conclusions: The results confirm the need to consider, in addition to noise, also some other NIHL risk factors, such as tobacco smoking, elevated blood pressure, and co-exposure to organic solvents when estimating the risk of NIHL and developing the hearing conservation programs for workers. Med Pr 2016;67(3:337–351

  4. [Do hearing threshold levels in workers of the furniture industry reflect their exposure to noise?].

    Science.gov (United States)

    Pawlaczyk-Łuszczyńska, Małgorzata; Dudarewicz, Adam; Czaja, Norman; Bortkiewicz, Alicja

    The aim of the study was to analyze the hearing status of employees of a furniture factory with respect to their exposure to noise and the presence of additional risk factors of noise-induced hearing loss (NIHL). Noise measurements, questionnaire survey and assessment of hearing, using pure tone audiometry, were carried out in 50 male workers, aged 20-57 years, directly employed in the manufacture of furniture. The actual workers' hearing threshold levels (HTLs) were compared with the predictions calculated according to PN-ISO 1999:2000 based on age, gender and noise exposure. Workers under study were exposed to noise at daily noise exposure levels of 82.7-94.8 dB (mean: 90.9 dB) for a period of 3-14 years. In all subjects, mean HTL at 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz did not exceed 25 dB. Nevertheless, high frequency notches were found in 11% of audiograms. The actual workers' HTLs at 3000-6000 Hz were similar to those predicted using PN-ISO 1999:2000. There were statistical significant differences between HTLs in subgroups of people with higher (> 78 mm Hg) and lower (≤ 78 mm Hg) diastolic blood pressure, smokers and non-smokers, and those working with organic solvents. Hearing loss was more evident in subjects affected by the additional risk factors specified above. The results confirm the need to consider, in addition to noise, also some other NIHL risk factors, such as tobacco smoking, elevated blood pressure, and co-exposure to organic solvents when estimating the risk of NIHL and developing the hearing conservation programs for workers. Med Pr 2016;67(3):337-351. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  5. Chronic Ethanol Exposure Effects on Vitamin D Levels among Subjects with Alcohol Use Disorder

    Directory of Open Access Journals (Sweden)

    Olalekan Ogunsakin

    2016-01-01

    Full Text Available Vitamin D has been previously recognized to play important roles in human immune system and function. In the pulmonary system, vitamin D regulates the function of antimicrobial peptides, especially cathelicidin/LL-37. Human cathelicidin/LL-37 is a bactericidal, bacteriostatic, and antiviral endogenous peptide with protective immune functions. Chronic exposure to excessive alcohol has the potential to reduce levels of vitamin D (inactive vitamin D [25(OHD 3 ] and active vitamin D [1, 25(OH 2 D 3 ] and leads to downregulation of cathelicidin/LL-37. Alcohol-mediated reduction of LL-37 may be partly responsible for increased incidence of more frequent and severe respiratory infections among subjects with alcohol use disorder (AUD. The objective of this study was to investigate the mechanisms by which alcohol exerts its influence on vitamin D metabolism. In addition, the aim was to establish associations between chronic alcohol exposures, levels of pulmonary vitamin D, and cathelicidin/LL-37 using broncho-alveolar lavage fluid samples of subjects with AUD and healthy controls. Findings from the experiment showed that levels of inactive vitamin D (25(OHD 3 , active vitamin D (1, 25(OH 2 D 3 , cathelicidin/LL-37, and CYP27B1 proteins were significantly reduced ( P < 0.05 when compared with the matched healthy control group. However, CYP2E1 was elevated in all the samples examined. Chronic exposure to alcohol has the potential to reduce the levels of pulmonary vitamin D and results in subsequent downregulation of the antimicrobial peptide, LL-37, in the human pulmonary system.

  6. Workplaces with elevated levels of exposure to natural radiation: The situation in Sweden

    International Nuclear Information System (INIS)

    Mjoenes, L.; Aakerblom, G.

    2002-01-01

    Because of the geological conditions with an abundance of granites and pegmatites rich in uranium and thorium together with large areas of uranium-rich alum shale, exposure from natural radiation is not unusual in certain types of industries and other work activities in Sweden. Although no representative survey of radon at regular workplaces has been performed in Sweden, smaller surveys and the high radon concentrations in dwellings indicate that workplaces with elevated radon levels are frequent in Sweden. Very high levels of indoor radon have been found in waterworks. Radon in mines has been regulated in Sweden since 1972 and radon in other workplaces since 1990. The situation in schools and day-care centres was thoroughly investigated in 2000. The estimated number of school and child care buildings with radon concentrations exceeding the action level 400 Bq/m 3 , is 800, about 200 of these have been identified and in about 100 buildings remedial measures have been taken. Regulations for natural radioactivity in building materials (for new buildings) have been in force since 1980. Lightweight concrete produced from uranium-rich alum shale was in use between 1929 and 1975. Almost 400,000 dwellings, 10 percent of the building stock, contain this material. The situation at NORM (Naturally Occurring Radioactive Material) industries is currently being investigated. Since the beginning of the 1950s it is known that residues from several industrial activities contain enhanced levels of natural radioactivity. Some examples are burnt alum shale from lime burning, radium-rich slag from metal production and waste gypsum from sulphuric acid production. The impact of the exposure from these residues is now being reinvestigated. So far no systematic search for up to now unknown work activities where substantial exposures from natural radiation could occur, has been initiated. For the protection of aircrew from cosmic radiation the responsible Swedish authorities have

  7. Low Level Laser Therapy Reduces the Development of Lung Inflammation Induced by Formaldehyde Exposure.

    Directory of Open Access Journals (Sweden)

    Cristiane Miranda da Silva

    Full Text Available Lung diseases constitute an important public health problem and its growing level of concern has led to efforts for the development of new therapies, particularly for the control of lung inflammation. Low Level Laser Therapy (LLLT has been highlighted as a non-invasive therapy with few side effects, but its mechanisms need to be better understood and explored. Considering that pollution causes several harmful effects on human health, including lung inflammation, in this study, we have used formaldehyde (FA, an environmental and occupational pollutant, for the induction of neutrophilic lung inflammation. Our objective was to investigate the local and systemic effects of LLLT after FA exposure. Male Wistar rats were exposed to FA (1% or vehicle (distillated water during 3 consecutive days and treated or not with LLLT (1 and 5 hours after each FA exposure. Non-manipulated rats were used as control. 24 h after the last FA exposure, we analyzed the local and systemic effects of LLLT. The treatment with LLLT reduced the development of neutrophilic lung inflammation induced by FA, as observed by the reduced number of leukocytes, mast cells degranulated, and a decreased myeloperoxidase activity in the lung. Moreover, LLLT also reduced the microvascular lung permeability in the parenchyma and the intrapulmonary bronchi. Alterations on the profile of inflammatory cytokines were evidenced by the reduced levels of IL-6 and TNF-α and the elevated levels of IL-10 in the lung. Together, our results showed that LLLT abolishes FA-induced neutrophilic lung inflammation by a reduction of the inflammatory cytokines and mast cell degranulation. This study may provide important information about the mechanisms of LLLT in lung inflammation induced by a pollutant.

  8. Low-level arsenic exposure via drinking water consumption and female fecundity - A preliminary investigation

    International Nuclear Information System (INIS)

    Susko, Michele L.; Bloom, Michael S.; Neamtiu, Iulia A.; Appleton, Allison A.; Surdu, Simona; Pop, Cristian; Fitzgerald, Edward F.; Anastasiu, Doru

    2017-01-01

    High level arsenic exposure is associated with reproductive toxicity in experimental and observational studies; however, few data exist to assess risks at low levels. Even less data are available to evaluate the impact of low level arsenic exposure on human fecundity. Our aim in this pilot study was a preliminary evaluation of associations between low level drinking water arsenic contamination and female fecundity. This retrospective study was conducted among women previously recruited to a hospital-based case-control study of spontaneous pregnancy loss in Timiá¹£ County, Romania. Women (n=94) with planned pregnancies of 5–20 weeks gestation completed a comprehensive physician-administered study questionnaire and reported the number of menstrual cycles attempting to conceive as the time to pregnancy (TTP). Drinking water samples were collected from residential drinking water sources and we determined arsenic levels using hydride generation-atomic absorption spectrometry (HG-AAS). Multivariable Cox-proportional hazards regression with Efron approximation was employed to evaluate TTP as a function of drinking water arsenic concentrations among planned pregnancies, adjusted for covariates. There was no main effect for drinking water arsenic exposure, yet the conditional probability for pregnancy was modestly lower among arsenic exposed women with longer TTPs, relative to women with shorter TTPs, and relative to unexposed women. For example, 1 µg/L average drinking water arsenic conferred 5%, 8%, and 10% lower likelihoods for pregnancy in the 6th, 9th, and 12th cycles, respectively (P=0.01). While preliminary, our results suggest that low level arsenic contamination in residential drinking water sources may further impair fecundity among women with longer waiting times; however, this hypothesis requires confirmation by a future, more definitive study. - Highlights: • We assessed low level drinking water arsenic as a predictor of fecundability. • Arsenic did

  9. Low-level arsenic exposure via drinking water consumption and female fecundity - A preliminary investigation

    Energy Technology Data Exchange (ETDEWEB)

    Susko, Michele L. [Department of Epidemiology and Biostatistics, University at Albany, State University of New York, Rensselaer, New York (United States); Bloom, Michael S., E-mail: mbloom@albany.edu [Department of Epidemiology and Biostatistics, University at Albany, State University of New York, Rensselaer, New York (United States); Department of Environmental Health Sciences, University at Albany, State University of New York, Rensselaer, New York (United States); Neamtiu, Iulia A. [Health Department, Environmental Health Center, Cluj-Napoca (Romania); IMOGEN Research Institute, Cluj-Napoca (Romania); Appleton, Allison A. [Department of Epidemiology and Biostatistics, University at Albany, State University of New York, Rensselaer, New York (United States); Surdu, Simona [Department of Environmental Health Sciences, University at Albany, State University of New York, Rensselaer, New York (United States); Pop, Cristian [Physico-chemical and Biotoxicological Analysis Laboratory, Environmental Health Center, Cluj-Napoca (Romania); Cluj School of Public Health - College of Political, Administrative and Communication Sciences, Babeș-Bolyai University, Cluj-Napoca (Romania); Faculty of Environmental Science and Engineering, Babeș-Bolyai University, Cluj-Napoca (Romania); Fitzgerald, Edward F. [Department of Epidemiology and Biostatistics, University at Albany, State University of New York, Rensselaer, New York (United States); Department of Environmental Health Sciences, University at Albany, State University of New York, Rensselaer, New York (United States); Anastasiu, Doru [University of Medicine and Pharmacy “Victor Babeș”, Timișoara (Romania); Obstetrics and Gynecology Department of the Emergency County Hospital, Timișoara (Romania); and others

    2017-04-15

    High level arsenic exposure is associated with reproductive toxicity in experimental and observational studies; however, few data exist to assess risks at low levels. Even less data are available to evaluate the impact of low level arsenic exposure on human fecundity. Our aim in this pilot study was a preliminary evaluation of associations between low level drinking water arsenic contamination and female fecundity. This retrospective study was conducted among women previously recruited to a hospital-based case-control study of spontaneous pregnancy loss in Timiá¹£ County, Romania. Women (n=94) with planned pregnancies of 5–20 weeks gestation completed a comprehensive physician-administered study questionnaire and reported the number of menstrual cycles attempting to conceive as the time to pregnancy (TTP). Drinking water samples were collected from residential drinking water sources and we determined arsenic levels using hydride generation-atomic absorption spectrometry (HG-AAS). Multivariable Cox-proportional hazards regression with Efron approximation was employed to evaluate TTP as a function of drinking water arsenic concentrations among planned pregnancies, adjusted for covariates. There was no main effect for drinking water arsenic exposure, yet the conditional probability for pregnancy was modestly lower among arsenic exposed women with longer TTPs, relative to women with shorter TTPs, and relative to unexposed women. For example, 1 µg/L average drinking water arsenic conferred 5%, 8%, and 10% lower likelihoods for pregnancy in the 6th, 9th, and 12th cycles, respectively (P=0.01). While preliminary, our results suggest that low level arsenic contamination in residential drinking water sources may further impair fecundity among women with longer waiting times; however, this hypothesis requires confirmation by a future, more definitive study. - Highlights: • We assessed low level drinking water arsenic as a predictor of fecundability. • Arsenic did

  10. In situ biomonitoring of juvenile Chinook salmon (Onchorhynchus tshawytscha) using biomarkers of chemical exposures and effects in a partially remediated urbanized waterway of the Puget Sound, WA

    Energy Technology Data Exchange (ETDEWEB)

    Browne, Eva [Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt Way Northeast, Suite 100, Seattle, WA 98105-6099 (United States); Kelley, Matthew; Zhou, Guo-Dong; He, Ling Yu; McDonald, Thomas; Wang, Shirley [Department of Environmental and Occupational Health, Texas A and M Health Science Center, College Station, TX 77843-1266 (United States); Duncan, Bruce [US Environmental Protection Agency, Region 10, 1200 Sixth Avenue, Seattle, WA 98101 (United States); Meador, James [Ecotoxicology Division, National Marine Fisheries Service, Seattle, WA 98105 (United States); Donnelly, Kirby [Department of Environmental and Occupational Health, Texas A and M Health Science Center, College Station, TX 77843-1266 (United States); Gallagher, Evan, E-mail: evang3@u.washington.edu [Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt Way Northeast, Suite 100, Seattle, WA 98105-6099 (United States)

    2010-10-15

    to 1160 ng/g at site B4, and there were no detectable waterborne PCBs at any of the sites (detection limit=10 ng/L). There were no significant differences (p<0.05) in biomarker gene expression in the Duwamish-caged fish relative to controls, although there was a pattern of gene expression suppression at site B3, the most heavily PAH-enriched site. The lack of a marked perturbation of mRNA biomarkers was consistent with relatively low levels of gill PAH-DNA adduct levels that did not differ among caged reference and field fish, and which were also consistent with relatively low waterborne concentrations of chemicals. The results of our study suggest a low bioavailability of sediment pollutants in caged juvenile Chinook potentially reflecting low waterborne exposures occurring at contaminated sites within the Duwamish waterway that have undergone partial remediation.

  11. Exposure levels of farmers and veterinarians to particulate matter and gases uring operational tasks in pig-fattening houses

    Directory of Open Access Journals (Sweden)

    Nele Van Ransbeeck

    2014-09-01

    Full Text Available The main objective of the study was to assess particulate matter (PM exposure levels for both the farmer and the veterinarian during different operational tasks in pig-fattening houses, and to estimate their exposure levels on a daily working basis (time-weighted average (TWA. The measured PM fractions were: inhalable and respirable PM, PM10, PM2.5 and PM1. The effects of pig age, pen floor type (conventional or low emission surface and cleaning of the pens on the personal PM exposure were also investigated. Indoor concentrations of NH[sub]3[/sub], CH[sub]4[/sub], and CO[sub]2[/sub] were additionally measured during some operational tasks. The results showed that personal exposure levels can become extremely high during some operational tasks performed by the farmer or veterinarian. The highest concentration levels were observed during feed shovelling and blood sampling, the lowest during the weighing of the pigs. For the farmer, the estimated TWA exposure levels of inhalable and respirable PM were 6.0 and 0.29 mg m[sup] -3[/sup] , respectively. These exposure levels for the veterinarian were, respectively, 10.6 and 0.74 mg m[sup] -3[/sup] . The PM concentration levels were mainly determined by the performed operational tasks. There was no significant effect of pig age, pen floor type, nor cleaning of the pens on the personal exposure levels.

  12. Association of umbilical cord blood lead with neonatal behavior at varying levels of exposure

    Directory of Open Access Journals (Sweden)

    Mamtani Manju R

    2006-06-01

    Full Text Available Abstract Background In the light of the ongoing debate about lowering the cut-off for acceptable blood lead level to Methods Using Brazelton's Neonatal Behavioral Assessment Scale (NBAS, an epidemiological approach and robust statistical techniques like multivariate linear regression, logistic regression, Poisson regression and structural equations modeling analyses we estimated the simultaneous indirect effects of umbilical cord blood lead (CBL levels and other neonatal covariates on the NBAS clusters. Results We observed that when analyzed in all study subjects, the CBL levels independently and strongly influenced autonomic stability and abnormal reflexes clusters. However, when the analysis was restricted to neonates with CBL Conclusion Our results further endorse the need to be cognizant of the detrimental effects of blood lead on neonates even at a low-dose prenatal exposure.

  13. Mapping very low level occupational exposure in medical imaging: A useful tool in risk communication and decision making

    Energy Technology Data Exchange (ETDEWEB)

    Covens, P., E-mail: pcovens@vub.ac.be [Health Physics Department, Vrije Universiteit Brussel and UZ Brussel, Laarbeeklaan 103, 1090 Brussels (Belgium); Beeldvorming en Fysische Wetenschappen (BEFY), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels (Belgium); Berus, D., E-mail: dberus@vub.ac.be [Health Physics Department, Vrije Universiteit Brussel and UZ Brussel, Laarbeeklaan 103, 1090 Brussels (Belgium); Mey, J. de, E-mail: Johan.DeMey@uzbrussel.be [Department of Radiology, UZ Brussel, Laarbeeklaan 101, 1090 Brussels (Belgium); Beeldvorming en Fysische Wetenschappen (BEFY), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels (Belgium); Buls, N., E-mail: Nico.Buls@uzbrussel.be [Department of Radiology, UZ Brussel, Laarbeeklaan 101, 1090 Brussels (Belgium); Beeldvorming en Fysische Wetenschappen (BEFY), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels (Belgium)

    2012-09-15

    Objectives: The use of ionising radiation in medical imaging is accompanied with occupational exposure which should be limited by optimised room design and safety instructions. These measures can however not prevent that workers are exposed to instantaneous dose rates, e.g. the residual exposure through shielding or the exposure of discharged nuclear medicine patients. The latter elements are often questioned by workers and detailed assessment should give more information about the impact on the individual radiation dose. Methods: Cumulated radiation exposure was measured in a university hospital during a period of 6 months by means of thermoluminescent dosimeters. Radiation exposure was measured at background locations and at locations where enhanced exposure levels are expected but where the impact on the individual exposure is unclear. Results: The results show a normal distribution of the cumulated background radiation level. No enhanced cumulated radiation exposure which significantly differs from this background level could be found during the operation of intra-oral apparatus, during ultrasonography procedures among nuclear medicine patients and at operator consoles of most CT-rooms. Conclusions: This 6 months survey offers useful information about occupational low level exposure in medical imaging and the findings can be useful in both risk communication and decision making.

  14. Mapping very low level occupational exposure in medical imaging: A useful tool in risk communication and decision making

    International Nuclear Information System (INIS)

    Covens, P.; Berus, D.; Mey, J. de; Buls, N.

    2012-01-01

    Objectives: The use of ionising radiation in medical imaging is accompanied with occupational exposure which should be limited by optimised room design and safety instructions. These measures can however not prevent that workers are exposed to instantaneous dose rates, e.g. the residual exposure through shielding or the exposure of discharged nuclear medicine patients. The latter elements are often questioned by workers and detailed assessment should give more information about the impact on the individual radiation dose. Methods: Cumulated radiation exposure was measured in a university hospital during a period of 6 months by means of thermoluminescent dosimeters. Radiation exposure was measured at background locations and at locations where enhanced exposure levels are expected but where the impact on the individual exposure is unclear. Results: The results show a normal distribution of the cumulated background radiation level. No enhanced cumulated radiation exposure which significantly differs from this background level could be found during the operation of intra-oral apparatus, during ultrasonography procedures among nuclear medicine patients and at operator consoles of most CT-rooms. Conclusions: This 6 months survey offers useful information about occupational low level exposure in medical imaging and the findings can be useful in both risk communication and decision making

  15. Association of dental enamel lead levels with risk factors for environmental exposure.

    Science.gov (United States)

    Olympio, Kelly Polido Kaneshiro; Naozuka, Juliana; Oliveira, Pedro Vitoriano; Cardoso, Maria Regina Alves; Bechara, Etelvino José Henriques; Günther, Wanda Maria Risso

    2010-10-01

    To analyze household risk factors associated with high lead levels in surface dental enamel. A cross-sectional study was conducted with 160 Brazilian adolescents aged 1418 years living in poor neighborhoods in the city of Bauru, southeastern Brazil, from August to December 2008. Body lead concentrations were assessed in surface dental enamel acid-etch microbiopsies. Dental enamel lead levels were measured by graphite furnace atomic absorption spectrometry and phosphorus levels were measured by inductively coupled plasma optical emission spectrometry. The parents answered a questionnaire about their children's potential early (05 years old) exposure to well-known lead sources. Logistic regression was used to identify associations between dental enamel lead levels and each environmental risk factor studied. Social and familial covariables were included in the models. The results suggest that the adolescents studied were exposed to lead sources during their first years of life. Risk factors associated with high dental enamel lead levels were living in or close to a contaminated area (OR = 4.49; 95% CI: 1.69;11.97); and member of the household worked in the manufacturing of paints, paint pigments, ceramics or batteries (OR = 3.43; 95% CI: 1.31;9.00). Home-based use of lead-glazed ceramics, low-quality pirated toys, anticorrosive paint on gates and/or sale of used car batteries (OR = 1.31; 95% CI: 0.56;3.03) and smoking (OR = 1.66; 95% CI: 0.52;5.28) were not found to be associated with high dental enamel lead levels. Surface dental enamel can be used as a marker of past environmental exposure to lead and lead concentrations detected are associated to well-known sources of lead contamination.

  16. Association of dental enamel lead levels with risk factors for environmental exposure

    Directory of Open Access Journals (Sweden)

    Kelly Polido Kaneshiro Olympio

    2010-10-01

    Full Text Available OBJECTIVE: To analyze household risk factors associated with high lead levels in surface dental enamel. METHODS: A cross-sectional study was conducted with 160 Brazilian adolescents aged 14-18 years living in poor neighborhoods in the city of Bauru, southeastern Brazil, from August to December 2008. Body lead concentrations were assessed in surface dental enamel acid-etch microbiopsies. Dental enamel lead levels were measured by graphite furnace atomic absorption spectrometry and phosphorus levels were measured by inductively coupled plasma optical emission spectrometry. The parents answered a questionnaire about their children's potential early (05 years old exposure to well-known lead sources. Logistic regression was used to identify associations between dental enamel lead levels and each environmental risk factor studied. Social and familial covariables were included in the models. RESULTS: The results suggest that the adolescents studied were exposed to lead sources during their first years of life. Risk factors associated with high dental enamel lead levels were living in or close to a contaminated area (OR = 4.49; 95% CI: 1.69;11.97; and member of the household worked in the manufacturing of paints, paint pigments, ceramics or batteries (OR = 3.43; 95% CI: 1.31;9.00. Home-based use of lead-glazed ceramics, low-quality pirated toys, anticorrosive paint on gates and/or sale of used car batteries (OR = 1.31; 95% CI: 0.56;3.03 and smoking (OR = 1.66; 95% CI: 0.52;5.28 were not found to be associated with high dental enamel lead levels. CONCLUSIONS: Surface dental enamel can be used as a marker of past environmental exposure to lead and lead concentrations detected are associated to well-known sources of lead contamination.

  17. Postnatal odorant exposure induces peripheral olfactory plasticity at the cellular level.

    Science.gov (United States)

    Cadiou, Hervé; Aoudé, Imad; Tazir, Bassim; Molinas, Adrien; Fenech, Claire; Meunier, Nicolas; Grosmaitre, Xavier

    2014-04-02

    Mammalian olfactory sensory neurons (OSNs) form the primary elements of the olfactory system. Inserted in the olfactory mucosa lining of the nasal cavity, they are exposed to the environment and their lifespan is brief. Several reports say that OSNs are regularly regenerated during the entire life and that odorant environment affects the olfactory epithelium. However, little is known about the impact of the odorant environment on OSNs at the cellular level and more precisely in the context of early postnatal olfactory exposure. Here we exposed MOR23-green fluorescent protein (GFP) and M71-GFP mice to lyral or acetophenone, ligands for MOR23 or M71, respectively. Daily postnatal exposure to lyral induces plasticity in the population of OSNs expressing MOR23. Their density decreases after odorant exposure, whereas the amount of MOR23 mRNA and protein remain stable in the whole epithelium. Meanwhile, quantitative PCR indicates that each MOR23 neuron has higher levels of olfactory receptor transcripts and also expresses more CNGA2 and phosphodiesterase 1C, fundamental olfactory transduction pathway proteins. Transcript levels return to baseline after 4 weeks recovery. Patch-clamp recordings reveal that exposed MOR23 neurons respond to lyral with higher sensitivity and broader dynamic range while the responses' kinetics were faster. These effects are specific to the odorant-receptor pair lyral-MOR23: there was no effect of acetophenone on MOR23 neurons and no effect of acetophenone and lyral on the M71 population. Together, our results clearly demonstrate that OSNs undergo specific anatomical, molecular, and functional adaptation when chronically exposed to odorants in the early stage of life.

  18. Chronic exposure to hypergravity affects thyrotropin-releasing hormone levels in rat brainstem and cerebellum

    Science.gov (United States)

    Daunton, N. G.; Tang, F.; Corcoran, M. L.; Fox, R. A.; Man, S. Y.

    1998-01-01

    In studies to determine the neurochemical mechanisms underlying adaptation to altered gravity we have investigated changes in neuropeptide levels in brainstem, cerebellum, hypothalamus, striatum, hippocampus, and cerebral cortex by radioimmunoassay. Fourteen days of hypergravity (hyperG) exposure resulted in significant increases in thyrotropin-releasing hormone (TRH) content of brainstem and cerebellum, but no changes in levels of other neuropeptides (beta-endorphin, cholecystokinin, met-enkephalin, somatostatin, and substance P) examined in these areas were found, nor were TRH levels significantly changed in any other brain regions investigated. The increase in TRH in brainstem and cerebellum was not seen in animals exposed only to the rotational component of centrifugation, suggesting that this increase was elicited by the alteration in the gravitational environment. The only other neuropeptide affected by chronic hyperG exposure was met-enkephalin, which was significantly decreased in the cerebral cortex. However, this alteration in met-enkephalin was found in both hyperG and rotation control animals and thus may be due to the rotational rather than the hyperG component of centrifugation. Thus it does not appear as if there is a generalized neuropeptide response to chronic hyperG following 2 weeks of exposure. Rather, there is an increase only of TRH and that occurs only in areas of the brain known to be heavily involved with vestibular inputs and motor control (both voluntary and autonomic). These results suggest that TRH may play a role in adaptation to altered gravity as it does in adaptation to altered vestibular input following labyrinthectomy, and in cerebellar and vestibular control of locomotion, as seen in studies of ataxia.

  19. [Internal Exposure Levels of PAHs of Primary School Students in Guangzhou].

    Science.gov (United States)

    Su, Hui; Zhao, Bo; Zhang, Su-kun; Liu, Shan; Ren, Ming-zhong; Li, Jie; Shi, Xiao-xia

    2015-12-01

    In order to investigate the internal exposure levels of polycyclic aromatic hydrocarbons (PAHs) in primary school students of Guangzhou, the research collected urine of 78 and 86 primary school students from two primary schools in the summer of 2014, one school located in the ordinary residential area and the other in the industrial area. The contents of 10 kinds of OH-PAHs were tested by the rapid liquid chromatography coupled to triple quadruple tandem mass spectrometry. The results showed that the concentrations of total OH-PAHs in primary school students in the residential zone ranged from 0.83 µmol · mol⁻¹ to 80.63 µmol · mol⁻¹, while those in industrial area ranged from 1.06 µmol · mol⁻¹ to 72.47 µmol · mol⁻¹. The geometric average concentrations were 6.18 µmol · mol⁻¹ and 6.47 µmol · mol⁻¹, respectively, and there was no statistical significance between them (P > 0.05). Comparison of the exposure levels of different components of PAHs in the two areas found that all the OH-PAHs had no significant difference except for the levels of 1- OHP (P transportation emissions.

  20. Radiation exposure and radon levels in some stations of the Syrian gas company

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Shwekani, R.; Jerbi, B.; Awad, I.

    2006-06-01

    In the present study, exposure levels and radon concentrations have been measured in natural gas production lines at the Syrian gas company. The study area includes gas stations for directories of Der Ezzor, Al-Jbessa, Al-Hassaka, and the middle region. The results showed that radiation exposure rates in remote stations and internal stations were within the natural levels except for two main locations, viz reflex pumps and propane production unites; 3 μSvhr -1 was reported. Radon concentration in Syrian natural gas varied between 15.4 Bqm - 3 and 1141 Bqm - 3; coproduced natural gas was found to contain higher concentration that the free natural gas. In addition, radon concentrations were higher in the central processing facilities that the well heads; these high levels are due to pressurizing and concentrating processes that enhance radon gas and its daughters concentrations in these stations. Moreover, a value of 659 Bqm - 3 in Al-Jbessa directorate gas and 225 Bqm - 3 in Al-Hassaka directorate gas were reported. While the concentration was lower in gas producing safur; a value of 80 Bqm - 3 was observed. On the other hand, maximum radon gas concentrations and its daughters in workplace air environment was found to be relatively high in the gas analysis laboratory and they are due to gas release inside the lab during analysis in addition to good separation of these laboratories from the surrounding environment. (author)

  1. Effects of Oral Exposure to Fungicides on Honey Bee Nutrition and Virus Levels.

    Science.gov (United States)

    Degrandi-Hoffman, Gloria; Chen, Yanping; Watkins Dejong, Emily; Chambers, Mona L; Hidalgo, Geoffrey

    2015-12-01

    Sublethal exposure to fungicides can affect honey bees (Apis mellifera L.) in ways that resemble malnutrition. These include reduced brood rearing, queen loss, and increased pathogen levels. We examined the effects of oral exposure to the fungicides boscalid and pyraclostrobin on factors affecting colony nutrition and immune function including pollen consumption, protein digestion, hemolymph protein titers, and changes in virus levels. Because the fungicides are respiratory inhibitors, we also measured ATP concentrations in flight muscle. The effects were evaluated in 3- and 7-d-old worker bees at high fungicide concentrations in cage studies, and at field-relevant concentrations in colony studies. Though fungicide levels differed greatly between the cage and colony studies, similar effects were observed. Hemolymph protein concentrations were comparable between bees feeding on pollen with and without added fungicides. However, in both cage and colony studies, bees consumed less pollen containing fungicides and digested less of the protein. Bees fed fungicide-treated pollen also had lower ATP concentrations and higher virus titers. The combination of effects we detected could produce symptoms that are similar to those from poor nutrition and weaken colonies making them more vulnerable to loss from additional stressors such as parasites and pathogens. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

  2. Investigation on the acceptance level of radiation exposure. Comparison of Chinese and Japanese

    International Nuclear Information System (INIS)

    Wu, Jin; Katoh, Kazuaki

    1999-01-01

    Radiation has helped to develop our culture and civilization, both of material and of spiritual, and without doubt it is useful to develop our civilization further and to enrich our future life. On the other hand, we cannot help avoiding to live with some by-product radiation of 'advanced civilization' in addition. Thus we must associate with radiation even if we like it or not. To our understanding, safety standard or criteria of safety control is nothing but a contract of the body concerned with the society. In order to make this contract rigorously, it is required for both sides to have adequately enough knowledge and data on the methodology of treating the matter. In such societies, people's acceptable levels to radiation exposure would not be widely distributed. Unification of the wills of the society is absolutely necessary to establish such a contact or develop the philosophy on radiation safety. Hence, we have tried to investigate the acceptable levels of people to radiation exposure. Two kinds of levels, upper limit of the acceptable dose for instantaneous whole body exposure, Lu, and lowest of the dose caring in mind, Ll, were set for inquiry. In this presentation, some results of our survey to both Chinese and Japanese professionals in the fields of science-technology and medical science are reported. Similarly to the previous study by Katoh, in 1989 or so, the distribution of these two levels were very broad and the band widths between the two levels, Lu and Ll, were quite narrow. The former seems reveal the variety of individual's sense of value. Moreover, it was found that, two levels, Lu and Ll, were significantly higher (p<0.05, p<0.005) in Japanese to in Chinese in science/engineering group, while in medical group, the two levels were higher apparently in Japanese than in Chinese, but no statistically significant difference was observed. Moreover, in medical group, Lu and Ll showed higher values than those in science-technology group for the

  3. The challenges of predicting pesticide exposure of honey bees at landscape level.

    Science.gov (United States)

    Simon-Delso, Noa; San Martin, Gilles; Bruneau, Etienne; Delcourt, Christine; Hautier, Louis

    2017-06-19

    To evaluate the risks of pesticides for pollinators, we must not only evaluate their toxicity but also understand how pollinators are exposed to these xenobiotics in the field. We focused on this last point and modeled honey bee exposure to pesticides at the landscape level. Pollen pellet samples (n = 60) from 40 Belgian apiaries were collected from late July to October 2011 and underwent palynological and pesticide residue analyses. Areas of various crops around each apiary were measured at 4 spatial scales. The most frequently detected pesticides were the fungicides boscalid (n = 19, 31.7%) and pyrimethanil (n = 10, 16.7%) and the insecticide dimethoate (n = 10, 16.7%). We were able to predict exposure probability for boscalid and dimethoate by using broad indicators of cropping intensity, but it remained difficult to identify the precise source of contamination (e.g. specific crops in which the use of the pesticide is authorized). For pyrimethanil, we were not able to build any convincing landscape model that could explain the contamination. Our results, combined with the late sampling period, strongly suggest that pesticides applied to crops unattractive to pollinators, and therefore considered of no risk for them, may be sources of exposure through weeds, drift to neighboring plants, or succeeding crops.

  4. Radioactivity levels in Indian coal and some technologically enhanced exposure to natural radiation environment of India

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Mishra, U.C.

    1988-01-01

    The summary of results of gamma-spectrometric measurements of natural radioactivity levels in coal from mines, coal, fly-ash, slag and soil samples from thermal power plants in India are presented. These constitute the sources of technologic ally enhanced exposures to natural radiation. Brief description of sampling and measurement procedure is given. Radiation dose to the population from coal fired power plants for electricity generation have been calculated using the model developed by UNSCEAR and ORNL reports with correction for local population density. (author). 13 refs., 7 tabs., 8 figs

  5. Exposure to PM2.5 and Blood Lead Level in Two Populations in Ulaanbaatar, Mongolia.

    Science.gov (United States)

    Enkhbat, Undarmaa; Rule, Ana M; Resnick, Carol; Ochir, Chimedsuren; Olkhanud, Purevdorj; Williams, D'Ann L

    2016-02-15

    Approximately 60% of the households in Ulaanbaatar live in gers (a traditional Mongolian dwelling) in districts outside the legal limits of the city, without access to basic infrastructure, such as water, sewage systems, central heating, and paved roads, in contrast to apartment residents. This stark difference in living conditions creates different public health challenges for Ulaanbaatar residents. Through this research study we aim to test our hypothesis that women living in gers burning coal in traditional stoves for cooking and heating during the winter are exposed to higher concentrations of airborne PM2.5 than women living in apartments in Ulaanbaatar, Mongolia, and this exposure may include exposures to lead in coal with effects on blood lead levels. This cross-sectional study recruited a total of 50 women, 40-60 years of age, from these two settings. Air sampling was carried out during peak cooking and heating times, 5:00 p.m.-11:00 p.m., using a direct-reading instrument (TSI SidePak™) and integrated polytetrafluoroethylene (PTFE) filters using the SKC Personal Environmental Monitor. Blood lead level (BLL) was measured using a LeadCare II rapid field test method. In our study population, measured PM2.5 geometric mean (GM) concentrations using the SidePak™ in the apartment group was 31.5 (95% CI:17-99) μg/m³, and 100 (95% CI: 67-187) μg/m³ in ger households (p < 0.001). The GM integrated gravimetric PM2.5 concentrations in the apartment group were 52.8 (95% CI: 39-297) μg/m³ and 127.8 (95% CI: 86-190) μg/m³ in ger households (p = 0.004). The correlation coefficient for the SidePak™ PM2.5 concentrations and filter based PM2.5 concentrations was r = 0.72 (p < 0.001). Blood Lead Levels were not statistically significant different between apartment residents and ger residents (p = 0.15). The BLL is statistically significant different (p = 0.01) when stratified by length of exposures outside of the home. This statistically significant difference

  6. Epidemiological methods of assessing risks from low level occupational exposure to ionising radiation

    International Nuclear Information System (INIS)

    Reissland, J.A.

    1982-01-01

    The resolution of radiation-attributable malignancies from the background of malignancies which are responsible for about 20% of all deaths in the Western world, presents a formidable challenge to epidemiological methods. Some of the major difficulties facing those with the task of estimating the risks associated with exposure to low level ionising radiation are discussed, particularly in the context of radiological protection. Some of the studies currently in progress are summarised and suggestions are made for other work which may help to contribute to a better understanding of the quantitative aspects of radiation risk assessment. (author)

  7. Limitations and problems in deriving risk estimates for low-level radiation exposure

    International Nuclear Information System (INIS)

    Cohen, B.L.

    1981-01-01

    Some of the problems in determining the cancer risk of low-level radiation from studies of exposed groups are reviewed and applied to the study of Hanford workers by Mancuso, Stewart, and Kneale. Problems considered are statistical limitations, variation of cancer rates with geography and race, the ''healthy worker effect,'' calendar year and age variation of cancer mortality, choosing from long lists, use of proportional mortality rates, cigarette smoking-cancer correlations, use of averages to represent data distributions, ignoring other data, and correlations between radiation exposure and other factors that may cause cancer. The current status of studies of the Hanford workers is reviewed

  8. Exposure to PM2.5 and Blood Lead Level in Two Populations in Ulaanbaatar, Mongolia

    Directory of Open Access Journals (Sweden)

    Undarmaa Enkhbat

    2016-02-01

    Full Text Available Approximately 60% of the households in Ulaanbaatar live in gers (a traditional Mongolian dwelling in districts outside the legal limits of the city, without access to basic infrastructure, such as water, sewage systems, central heating, and paved roads, in contrast to apartment residents. This stark difference in living conditions creates different public health challenges for Ulaanbaatar residents. Through this research study we aim to test our hypothesis that women living in gers burning coal in traditional stoves for cooking and heating during the winter are exposed to higher concentrations of airborne PM2.5 than women living in apartments in Ulaanbaatar, Mongolia, and this exposure may include exposures to lead in coal with effects on blood lead levels. This cross-sectional study recruited a total of 50 women, 40–60 years of age, from these two settings. Air sampling was carried out during peak cooking and heating times, 5:00 p.m.–11:00 p.m., using a direct-reading instrument (TSI SidePak™ and integrated polytetrafluoroethylene (PTFE filters using the SKC Personal Environmental Monitor. Blood lead level (BLL was measured using a LeadCare II rapid field test method. In our study population, measured PM2.5 geometric mean (GM concentrations using the SidePak™ in the apartment group was 31.5 (95% CI:17–99 μg/m3, and 100 (95% CI: 67–187 μg/m3 in ger households (p < 0.001. The GM integrated gravimetric PM2.5 concentrations in the apartment group were 52.8 (95% CI: 39–297 μg/m3 and 127.8 (95% CI: 86–190 μg/m3 in ger households (p = 0.004. The correlation coefficient for the SidePak™ PM2.5 concentrations and filter based PM2.5 concentrations was r = 0.72 (p < 0.001. Blood Lead Levels were not statistically significant different between apartment residents and ger residents (p = 0.15. The BLL is statistically significant different (p = 0.01 when stratified by length of exposures outside of the home. This statistically

  9. An influence of occupational exposure on level of chromosome aberrations in nuclear power plant workers

    International Nuclear Information System (INIS)

    Birute Griciene; Grazina Slapsyte

    2007-01-01

    analyzed for chromosome aberrations. Results. Chromosome aberration analyses revealed significant increase in the total chromosome aberration frequency for the radiation workers with internal exposure (2.42±0.40 CA/100 cells, P=0.01) and for those with additional neutron exposure (2.63±0.40 CA/100 cells, P=0.01). However, no significant differences between the workers with external gamma radiation exposure and the controls (1.62±0.25 vs. 1.65±0.15 CA/100 cells, P=0.83) was observed. There was no correlation between the chromosome aberration frequency and the cumulative dose, mean annual doses averaged over the last 3-years or the last year before the blood sampling. The confounding effects of internal and neutron exposure on the frequency of chromosome aberrations was determined. The impact of other factors (smoking habits, age, duration of employment, cumulative dose) was found to be not significant. Conclusion. Though no increase in chromosome aberration frequency was determined in workers exposed to external gamma radiation only, the demonstration of the elevated levels of chromosome aberrations in the workers with incorporated radionuclides and neutron exposure indicates their more hazardous work activities with consequential risk to health.

  10. Environmental and occupational exposure to bisphenol A and endometriosis: urinary and peritoneal fluid concentration levels.

    Science.gov (United States)

    Simonelli, Angela; Guadagni, Rossella; De Franciscis, Pasquale; Colacurci, Nicola; Pieri, Maria; Basilicata, Pascale; Pedata, Paola; Lamberti, Monica; Sannolo, Nicola; Miraglia, Nadia

    2017-01-01

    The study aimed to give a first data set of bisphenol A (BPA) levels in the peritoneal fluid of patients suffering from endometriosis and to investigate the relationship between BPA exposure and endometriosis. A questionnaire investigating the occupational context, life environment, and habits was administered to 68 patients suffering from endometriosis and 60 endometriosis-free subjects (control group). Urine and peritoneal fluids samples were collected and analysed by GC/MSMS for BPA dosage. Some of the investigated environmental/lifestyle risk factors (closeness to industries/activities at risk) were associated with an increase in endometriosis; smoking resulted as protective factor; others (use of food plastic boxes) did not seem to influence the onset of pathology. The association between the occupational exposure summarising all examined risk factors (working activity, personal protective equipment, seniority) and endometriosis was statistically significant (χ 2  = 5.252, p = 0.02). Contrasting results were obtained when specific activities were examined. Detectable urinary BPA levels were found in all analysed samples (patients: 1.17-12.68 pg/µl; mean ± SD, 5.31 ± 3.36 pg/µl; control group: 1.28-2.35 pg/µl; mean ± SD, 1.64 ± 0.49 pg/µl; median; 1.46 pg/µl), with a statistically significant difference between patients and controls, showing an association between BPA exposure and endometriosis. Only a few subjects from the control group supplied peritoneal fluid; hence, no comparison test with patients (range 0.39-1.46 pg/µl; mean ± SD, 0.67 ± 0.30 pg/µl; median, 0.58 pg/µl) was carried out. Results highlight the potential association between BPA exposure and endometriosis, as well as the current lack of knowledge regarding occupational exposure to BPA and the need of epidemiological studies focused on single activities/occupations, such as housewives, cleaners, students.

  11. Validation of Sea levels from coastal altimetry waveform retracking expert system: a case study around the Prince William Sound in Alaska

    Science.gov (United States)

    Idris, N. H.; Deng, X.; Idris, N. H.

    2017-05-01

    This paper presents the validation of Coastal Altimetry Waveform Retracking Expert System (CAWRES), a novel method to optimize the Jason satellite altimetric sea levels from multiple retracking solutions. The validation is conducted over the region of Prince William Sound in Alaska, USA, where altimetric waveforms are perturbed by emerged land and sea states. Validation is performed in twofold. First, comparison with existing retrackers (i.e. MLE4 and Ice) from the Sensor Geophysical Data Records (SGDR), and second, comparison with in-situ tide gauge data. From the first validation assessment, in general, CAWRES outperforms the MLE4 and Ice retrackers. In 4 out of 6 cases, the value of improvement percentage (standard deviation of difference) is higher (lower) than those of the SGDR retrackers. CAWRES also presents the best performance in producing valid observations, and has the lowest noise when compared to the SGDR retrackers. From the second assessment with tide gauge, CAWRES retracked sea level anomalies (SLAs) are consistent with those of the tide gauge. The accuracy of CAWRES retracked SLAs is slightly better than those of the MLE4. However, the performance of Ice retracker is better than those of CAWRES and MLE4, suggesting the empirical-based retracker is more effective. The results demonstrate that the CAWRES would have potential to be applied to coastal regions elsewhere.

  12. Early life low-level cadmium exposure is positively associated with increased oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Kippler, Maria [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden); Bakhtiar Hossain, Mohammad [International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), Dhaka 1212 (Bangladesh); Department of Laboratory Medicine, Section of Occupational and Environmental Medicine, Lund University, Lund (Sweden); Lindh, Christian [International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), Dhaka 1212 (Bangladesh); Moore, Sophie E. [MRC Keneba, MRC Laboratories (Gambia); Kabir, Iqbal [Department of Laboratory Medicine, Section of Occupational and Environmental Medicine, Lund University, Lund (Sweden); Vahter, Marie [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden); Broberg, Karin, E-mail: karin.broberg_palmgren@med.lu.se [International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), Dhaka 1212 (Bangladesh)

    2012-01-15

    Environmental exposure to cadmium (Cd) is known to induce oxidative stress, a state of imbalance between the production of reactive oxygen species (ROS) and the ability to detoxify them, in adults. However, data are lacking on potential effects in early-life. We evaluated urinary concentrations of 8-oxo-7,8-dihydro-2 Prime -deoxyguanosine (8-oxodG), a recognized marker of oxidative DNA damage, in relation to Cd exposure in 96 predominantly breast-fed infants (11-17 weeks of age) in rural Bangladesh. Urinary 8-oxodG was measured using liquid chromatography tandem mass spectrometry and Cd in urine and breast milk by inductively coupled plasma mass spectrometry. Median concentration of 8-oxodG was 3.9 nmol/L, urinary Cd 0.30 {mu}g/L, and breast-milk Cd 0.13 {mu}g/L. In linear regression analyses, urinary 8-oxodG was positively associated with Cd in both urine (p=0.00067) and breast milk (p=0.0021), and negatively associated with body weight (kg; p=0.0041). Adjustment for age, body weight, socio-economic status, urinary arsenic, as well as magnesium, calcium, and copper in breast milk did not change the association between Cd exposure and urinary 8-oxodG. These findings suggest that early-life low-level exposure to Cd via breast milk induces oxidative stress. Further studies are warranted to elucidate whether this oxidative stress is associated with impaired child health and development.

  13. Early life low-level cadmium exposure is positively associated with increased oxidative stress

    International Nuclear Information System (INIS)

    Kippler, Maria; Bakhtiar Hossain, Mohammad; Lindh, Christian; Moore, Sophie E.; Kabir, Iqbal; Vahter, Marie; Broberg, Karin

    2012-01-01

    Environmental exposure to cadmium (Cd) is known to induce oxidative stress, a state of imbalance between the production of reactive oxygen species (ROS) and the ability to detoxify them, in adults. However, data are lacking on potential effects in early-life. We evaluated urinary concentrations of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG), a recognized marker of oxidative DNA damage, in relation to Cd exposure in 96 predominantly breast-fed infants (11–17 weeks of age) in rural Bangladesh. Urinary 8-oxodG was measured using liquid chromatography tandem mass spectrometry and Cd in urine and breast milk by inductively coupled plasma mass spectrometry. Median concentration of 8-oxodG was 3.9 nmol/L, urinary Cd 0.30 μg/L, and breast-milk Cd 0.13 μg/L. In linear regression analyses, urinary 8-oxodG was positively associated with Cd in both urine (p=0.00067) and breast milk (p=0.0021), and negatively associated with body weight (kg; p=0.0041). Adjustment for age, body weight, socio-economic status, urinary arsenic, as well as magnesium, calcium, and copper in breast milk did not change the association between Cd exposure and urinary 8-oxodG. These findings suggest that early-life low-level exposure to Cd via breast milk induces oxidative stress. Further studies are warranted to elucidate whether this oxidative stress is associated with impaired child health and development.

  14. Investigation of the exposure level of electromagnetic fields produced by mobile telephone base stations

    International Nuclear Information System (INIS)

    Abukassem, I.; Kharita, M. H.

    2010-12-01

    The aim of this work is to investigate the real values of microwave level distribution and propagation in the locality around samples of mobile phone base station, and to compare the results with the exposure restriction limits recommenced by the International Commission on Non Ionizing Radiation Protection (ICNIRP). Measurements were performed using special meters for microwaves; the first (Narda SRM-3000) is used for electromagnetic waves frequency spectrum scanning and the second (NARDA) emr 300) determine the level of electric and magnetic fields and the power density of these waves nearby any sort of transmitters. Samples of different kinds of mobile phone base station were chosen to cover important zones of Damascus, and the region around each base station was also scanned in the emission direction and according to accessibility into the studies positions. Results showed that the signal level in all measured points is lower than the ICNIRP restriction level, but for few points the detected microwave level has relatively important values. The signal level inside building situated partially in the emission direction of the base station transmitters decreases stepwise and walls reduce considerably the signal intensity. To realize these kind of field studies in the best way and obtain the maximum profits for all people, the properties and operating system of transmitters used in mobile phone base station must be known, and therefore, it is very important to achieve a transparent collaboration between research laboratory and mobile phone company. (author)

  15. Sound knowledge

    DEFF Research Database (Denmark)

    Kauffmann, Lene Teglhus

    as knowledge based on reflexive practices. I chose ‘health promotion’ as the field for my research as it utilises knowledge produced in several research disciplines, among these both quantitative and qualitative. I mapped out the institutions, actors, events, and documents that constituted the field of health...... of the research is to investigate what is considered to ‘work as evidence’ in health promotion and how the ‘evidence discourse’ influences social practices in policymaking and in research. From investigating knowledge practices in the field of health promotion, I develop the concept of sound knowledge...... result of a rigorous and standardized research method. However, this anthropological analysis shows that evidence and evidence-based is a hegemonic ‘way of knowing’ that sometimes transposes everyday reasoning into an epistemological form. However, the empirical material shows a variety of understandings...

  16. [Effects of intermittent hypoxic exposure on the parameter of erythrocyte and serum hypoxia inducible factor-1 alpha and erythropoietin levels].

    Science.gov (United States)

    Zhang, Cheng-yan; Zhang, Ji-xin; Lü, Xiao-tao; Li, Bao-yu

    2009-10-01

    To investigate the effects of intermittent hypoxic exposure and normoxic convalescence on the parameter of erythrocyte and serum hypoxia inducible factor-1 alpha (HIF-1alpha) and erythropoietin (EPO) levels. Rat models of intermittent hypoxic exposure were established, combined with the clinical research on volunteers experiencing the intermittent plateau work. Blood samples for red blood cell (RBC) counts, hemoglobin (Hb) and hematocrit (HCT) were collected, serum HIF-1alpha and EPO levels were measured using enzyme linked immunosorbent assay. RBC counts, Hb concentration and HCT were significantly higher than the normoxic group (P hypoxic exposure can enhance serum hypoxia inducible factor-1 alpha and erythropointin levels and the generation of red blood cells, which leads to an increase in hemoglobin concentration and hematocrit. The results have changed with the hypoxic exposure period prolonged. Normoxic convalescence after intermittent hypoxic exposure can make the related indexes reduced, and contribute to the organism recovery.

  17. Exposure to Elevated Carbon Monoxide Levels at an Indoor Ice Arena--Wisconsin, 2014.

    Science.gov (United States)

    Creswell, Paul D; Meiman, Jon G; Nehls-Lowe, Henry; Vogt, Christy; Wozniak, Ryan J; Werner, Mark A; Anderson, Henry

    2015-11-20

    On December 13, 2014, the emergency management system in Lake Delton, Wisconsin, was notified when a male hockey player aged 20 years lost consciousness after participation in an indoor hockey tournament that included approximately 50 hockey players and 100 other attendees. Elevated levels of carbon monoxide (CO) (range = 45 ppm-165 ppm) were detected by the fire department inside the arena. The emergency management system encouraged all players and attendees to seek medical evaluation for possible CO poisoning. The Wisconsin Department of Health Services (WDHS) conducted an epidemiologic investigation to determine what caused the exposure and to recommend preventive strategies. Investigators abstracted medical records from area emergency departments (EDs) for patients who sought care for CO exposure during December 13-14, 2014, conducted a follow-up survey of ED patients approximately 2 months after the event, and conducted informant interviews. Ninety-two persons sought ED evaluation for possible CO exposure, all of whom were tested for CO poisoning. Seventy-four (80%) patients had blood carboxyhemoglobin (COHb) levels consistent with CO poisoning; 32 (43%) CO poisoning cases were among hockey players. On December 15, the CO emissions from the propane-fueled ice resurfacer were demonstrated to be 4.8% of total emissions when actively resurfacing and 2.3% when idling, both above the optimal range of 0.5%-1.0%. Incomplete fuel combustion by the ice resurfacer was the most likely source of elevated CO. CO poisonings in ice arenas can be prevented through regular maintenance of ice resurfacers, installation of CO detectors, and provision of adequate ventilation.

  18. Increased levels of oxidative DNA damage attributable to cooking-oil fumes exposure among cooks.

    Science.gov (United States)

    Ke, Yuebin; Cheng, Jinquan; Zhang, Zhicheng; Zhang, Renli; Zhang, Zhunzhen; Shuai, Zhihong; Wu, Tangchun

    2009-07-01

    Previous investigations have indicated that cooks are exposed to polycyclic aromatic hydrocarbons (PAHs) from cooking-oil fumes. However, Emission of PAH and their carcinogenic potencies from cooking oil fumes sources have not been investigated among cooks. To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxyguanosine (8-OHdG), in different groups of cooks and different exposure groups, and to study the association between 8-OHdG and 1-hydroxypyrene(1-OHP), a biological marker for PAH exposure. Urine samples were collected from different groups of cooks (n = 86) and from unexposed controls (n = 36); all were male with similar age and smoking habits. The health status, occupational history, smoking, and alcohol consumption 24 h prior to sampling was estimated from questionnaires. The urine samples were frozen for later analyses of 8-OHdG and 1-OHP levels by high-performance liquid chromatography. Excretion in urine of 8-OHdG was similar for controls (mean 1.2micromol/mol creatinine, n = 36), and for those who had been in the kitchen with an exhaust-hood operating (mean 1.5micromol/mol creatinine, n = 45). Cooks exposed to cooking-oil fumes without exhaust-hood operation had significantly increased excretion of 8-OHdG (mean 2.3micromol/mol creatinine, n = 18), compared with controls. The urinary levels of ln 1-OHP and ln 8-OHdG were still significantly correlated in a multiple regression analysis. The results indicate that exposure to PAH or possibly other compounds in cooking-oil fumes may cause oxidative DNA damage.

  19. Chronic exposure to low-levels of lead in the rat: biochemical and behavioural changes

    International Nuclear Information System (INIS)

    Rossouw, J.

    1987-01-01

    The prevalence of lead in the environment is a cause of continuing toxicology concern and there have been numerous human and animal studies to examine more thoroughly the possible consequences of exposure to this ecotoxicant. Because lead is highly toxic to the developing central nervous system, increasing concern over the rise in the lead content in the environment has been expressed. These concerns seem appropriate since more recent clinical studies have shown that prolonged exposure of children to so called 'subclinical' concentrations of lead may be associated with behavioural disorders, learning disabilities and mental retardation. Moreover, animal studies have shown that chronic perinatal low-level lead exposure elicits alterations in both learned and spontaneous behavioural patterns in the absence of typical outward signs of lead-induced neurological toxicity. No study however could relate behavioural changes to specific alterations in neurochemisty. The aim of this study was therefore to expose rats, in different stages of their development, to low-levels of lead in order to induce behavioural disorders and correlate latter with possible neurochemical changes. In accordance with the general aims of the study, the structuring of the thesis is as follows: (a) a discussion of the neurotransmitters in the brain in order to describe the different systems which have been investigated; (b) a review of appropriate literature regarding the kinetics, toxodynamics and neurotoxicity of lead and (c) a summary of the methods employed in the study. The following results are presented: (d) the effects of lead treatment on physical development of the rats; (e) the induction of behavioural supersensitivity and (f) the effects lead has on central receptors

  20. Bronchoalveolar lavage analysis, gallium-67 lung scanning and soluble interleukin-2 receptor levels in asbestos exposure

    International Nuclear Information System (INIS)

    Delclos, G.L.; Flitcraft, D.G.; Brousseau, K.P.; Windsor, N.T.; Nelson, D.L.; Wilson, R.K.; Lawrence, E.C.

    1989-01-01

    This study examined different markers of lung immunologic and inflammatory responses to previous asbestos exposure. We performed bronchoalveolar lavage (BAL) and gallium-67 ( 67 Ga) lung scans and measured serum and BAL soluble interleukin-2 receptor (IL-2R) and angiotensin-converting enzyme (SACE) levels in 32 subjects with a history of significant asbestos exposure, 14 without (EXP) and 18 with (ASB) radiographic evidence of asbestosis. BAL analysis revealed increases in neutrophils in both ASB and EXP when compared to controls (P less than 0.01), which persisted after adjustment for smoking category. Although significant abnormalities of macrophage and total lymphocyte profiles were not found in the study population, lymphocyte subpopulation analysis revealed elevation of BAL T4/T8 ratios in the entire study group (ASB + EXP) when compared to controls (P less than 0.05), independent of smoking category. 67 Ga lung scan activity was increased in 56% of ASB and in 36% of EXP: no correlations between positive scans and different radiological and functional parameters could be found. There was no significant elevation of mean SACE, serum, or BAL IL-2R levels in any of the study categories. These data suggest that asbestos exposure may be associated with parenchymal inflammation, even in the absence of clinical criteria for asbestosis. Abnormalities of gallium uptake and of BAL analysis reflect the clinically inapparent inflammation. The increased BAL T4/T8 ratios observed suggest that abnormal local pulmonary immunoregulation may play a role in the pathogenesis of asbestos-related lung diseases

  1. Exposure to environmentally-relevant levels of ozone negatively influence pollen and fruit development

    International Nuclear Information System (INIS)

    Gillespie, Colin; Stabler, Daniel; Tallentire, Eva; Goumenaki, Eleni; Barnes, Jeremy

    2015-01-01

    A combination of in vitro and in vivo studies on tomato (Lycopersicon esculentum Mill. cv. Triton) revealed that environmentally-relevant levels of ozone (O_3) pollution adversely affected pollen germination, germ tube growth and pollen-stigma interactions – pollen originating from plants raised in charcoal-Purafil"® filtered air (CFA) exhibited reduced germ tube development on the stigma of plants exposed to environmentally-relevant levels of O_3. The O_3-induced decline in in vivo pollen viability was reflected in increased numbers of non-fertilized and fertilized non-viable ovules in immature fruit. Negative effects of O_3 on fertilization occurred regardless of the timing of exposure, with reductions in ovule viability evident in O_3 × CFA and CFA × O_3 crossed plants. This suggests O_3-induced reductions in fertilization were associated with reduced pollen viability and/or ovule development. Fruit born on trusses independently exposed to 100 nmol mol"−"1 O_3 (10 h d"−"1) from flowering exhibited a decline in seed number and this was reflected in a marked decline in the weight and size of individual fruit – a clear demonstration of the direct consequence of the effects of the pollutant on reproductive processes. Ozone exposure also resulted in shifts in the starch and ascorbic acid (Vitamin C) content of fruit that were consistent with accelerated ripening. The findings of this study draw attention to the need for greater consideration of, and possibly the adoption of weightings for the direct impacts of O_3, and potentially other gaseous pollutants, on reproductive biology during ‘risk assessment’ exercises. - Highlights: • Environmentally-relevant levels of ozone exert negative effects on pollen viability that translate into direct impacts on fruit yield. • Negative impacts of O_3 pollution on reproductive processes were evident regardless of the stage of plant development. • Exposure to environmentally-relevant levels of O_3

  2. Determination of sound types and source levels of airborne vocalizations by California sea lions, Zalophus californianus, in rehabilitation at the Marine Mammal Center in Sausalito, California

    Science.gov (United States)

    Schwalm, Afton Leigh

    California sea lions (Zalophus californianus) are a highly popular and easily recognized marine mammal in zoos, aquariums, circuses, and often seen by ocean visitors. They are highly vocal and gregarious on land. Surprisingly, little research has been performed on the vocalization types, source levels, acoustic properties, and functions of airborne sounds used by California sea lions. This research on airborne vocalizations of California sea lions will advance the understanding of this aspect of California sea lions communication, as well as examine the relationship between health condition and acoustic behavior. Using a PhillipsRTM digital recorder with attached microphone and a calibrated RadioShackRTM sound pressure level meter, acoustical data were recorded opportunistically on California sea lions during rehabilitation at The Marine Mammal Center in Sausalito, CA. Vocalizations were analyzed using frequency, time, and amplitude variables with Raven Pro: Interactive Sound Analysis Software Version 1.4 (The Cornell Lab of Ornithology, Ithaca, NY). Five frequency, three time, and four amplitude variables were analyzed for each vocalization. Differences in frequency, time, and amplitude variables were not significant by sex. The older California sea lion group produced vocalizations that were significantly lower in four frequency variables, significantly longer in two time variables, significantly higher in calibrated maximum and minimum amplitude variables, and significantly lower in frequency at maximum and minimum amplitude compared with pups. Six call types were identified: bark, goat, growl/grumble, bark/grumble, bark/growl, and grumble/moan. The growl/grumble call was higher in dominant beginning, ending, and minimum frequency, as well as in the frequency at maximum amplitude compared with the bark, goat, bark/grumble calls in the first versus last vocalization sample. The goat call was significantly higher in first harmonic interval than any other call type

  3. Impact of some field factors on inhalation exposure levels to bitumen emissions during road paving operations.

    Science.gov (United States)

    Deygout, François; Auburtin, Guy

    2015-03-01

    Variability in occupational exposure levels to bitumen emissions has been observed during road paving operations. This is due to recurrent field factors impacting the level of exposure experienced by workers during paving. The present study was undertaken in order to quantify the impact of such factors. Pre-identified variables currently encountered in the field were monitored and recorded during paving surveys, and were conducted randomly covering current applications performed by road crews. Multivariate variance analysis and regressions were then used on computerized field data. The statistical investigations were limited due to the relatively small size of the study (36 data). Nevertheless, the particular use of the step-wise regression tool enabled the quantification of the impact of several predictors despite the existing collinearity between variables. The two bitumen organic fractions (particulates and volatiles) are associated with different field factors. The process conditions (machinery used and delivery temperature) have a significant impact on the production of airborne particulates and explain up to 44% of variability. This confirms the outcomes described by previous studies. The influence of the production factors is limited though, and should be complemented by studying factors involving the worker such as work style and the mix of tasks. The residual volatile compounds, being part of the bituminous binder and released during paving operations, control the volatile emissions; 73% of the encountered field variability is explained by the composition of the bitumen batch. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  4. Application of a pilot control banding tool for risk level assessment and control of nanoparticle exposures.

    Science.gov (United States)

    Paik, Samuel Y; Zalk, David M; Swuste, Paul

    2008-08-01

    Control banding (CB) strategies offer simplified solutions for controlling worker exposures to constituents that are found in the workplace in the absence of firm toxicological and exposure data. These strategies may be particularly useful in nanotechnology applications, considering the overwhelming level of uncertainty over what nanomaterials and nanotechnologies present as potential work-related health risks, what about these materials might lead to adverse toxicological activity, how risk related to these might be assessed and how to manage these issues in the absence of this information. This study introduces a pilot CB tool or 'CB Nanotool' that was developed specifically for characterizing the health aspects of working with engineered nanoparticles and determining the level of risk and associated controls for five ongoing nanotechnology-related operations being conducted at two Department of Energy research laboratories. Based on the application of the CB Nanotool, four of the five operations evaluated in this study were found to have implemented controls consistent with what was recommended by the CB Nanotool, with one operation even exceeding the required controls for that activity. The one remaining operation was determined to require an upgrade in controls. By developing this dynamic CB Nanotool within the realm of the scientific information available, this application of CB appears to be a useful approach for assessing the risk of nanomaterial operations, providing recommendations for appropriate engineering controls and facilitating the allocation of resources to the activities that most need them.

  5. Does exposure to very high levels of natural radiation induce hematological alterations in humans?

    International Nuclear Information System (INIS)

    Ghiassi-Nejad, M.

    2003-01-01

    Full text: It has long been known that total body exposure to moderate doses decrease the number of circulating erythrocytes, platelets, granulocytes, and lymphocytes. However, data on hematopoietic effects of exposure to very low doses of ionizing radiation in humans are scarce. Recently it has been reported that hematological parameters have significant positive associations with the radiation dose received by residents lived near a nuclear power plant. Ramsar, a city in northern Iran, has some inhabited areas with the highest levels of natural radiation studied so far. A population of about 2000 is exposed to average annual radiation levels of 10.2 mGy y -1 and the highest recorded external gamma dose rates are about 130 mGy y -1 . In this study, hematological parameters such as counts of leukocytes, lymphocytes, monocytes, granulocytes, red blood cells, hemoglobin, hematocrit, MCV, MCH, MCHC, RDW, PLT, and MPV were measured in the inhabitants. The results of this study indicated that there was no any statistically significant alteration in hematological parameters of the inhabitants of very high background radiation areas of Ramsar compared to those of a neighboring control area

  6. Estimation of Radiofrequency Power Leakage from Microwave Ovens for Dosimetric Assessment at Nonionizing Radiation Exposure Levels

    Directory of Open Access Journals (Sweden)

    Peio Lopez-Iturri

    2015-01-01

    Full Text Available The electromagnetic field leakage levels of nonionizing radiation from a microwave oven have been estimated within a complex indoor scenario. By employing a hybrid simulation technique, based on coupling full wave simulation with an in-house developed deterministic 3D ray launching code, estimations of the observed electric field values can be obtained for the complete indoor scenario. The microwave oven can be modeled as a time- and frequency-dependent radiating source, in which leakage, basically from the microwave oven door, is propagated along the complete indoor scenario interacting with all of the elements present in it. This method can be of aid in order to assess the impact of such devices on expected exposure levels, allowing adequate minimization strategies such as optimal location to be applied.

  7. Exposure level and distribution characteristics of airborne bacteria and fungi in Seoul metropolitan subway stations.

    Science.gov (United States)

    Kim, Ki Youn; Kim, Yoon Shin; Kim, Daekeun; Kim, Hyeon Tae

    2011-01-01

    The exposure level and distribution characteristics of airborne bacteria and fungi were assessed in the workers' activity areas (station office, bedroom, ticket office and driver's seat) and passengers' activity areas (station precinct, inside the passenger carriage, and platform) of the Seoul metropolitan subway. Among investigated areas, the levels of airborne bacteria and fungi in the workers' bedroom and station precincts were relatively high. No significant difference was found in the concentration of airborne bacteria and fungi between the underground and above ground activity areas of the subway. The genera identified in all subway activity areas with a 5% or greater detection rate were Staphylococcus, Micrococcus, Bacillus and Corynebacterium for airborne bacteria and Penicillium, Cladosporium, Chrysosporium, Aspergillus for airborne fungi. Staphylococcus and Micrococcus comprised over 50% of the total airborne bacteria and Penicillium and Cladosporium comprised over 60% of the total airborne fungi, thus these four genera are the predominant genera in the subway station.

  8. Fluoride Ion Regeneration of Cyclosarin (GF) From Rat Blood Following Whole-Body Exposure to Lethal Levels of GF Vapor

    National Research Council Canada - National Science Library

    Jakubowski, E. M; Anthony, J. S; Mioduszewski, R. J; Manthei, J. H; Burnett, D. C; Way, R. A; Gaviola, B. I; Scotto, J. A; Muse, W. T; Whalley, C. E

    2003-01-01

    .... Levels of exposure ranged from 2 mg/m3 for 240 min to 41.9 mg/m3 for 10 min. The GF biomarker found in rat plasma and red blood cell samples was regenerated GF, which is the product of adding fluoride ion at pH 4 to the post exposure samples...

  9. Association between Blood Dioxin Level and Chronic Kidney Disease in an Endemic Area of Exposure.

    Directory of Open Access Journals (Sweden)

    Chien-Yuan Huang

    Full Text Available Dioxin is an industrial pollutant related to various diseases, but epidemiological data on its effects on the kidney are limited. Therefore, we conducted a study to evaluate the association between dioxin exposure and chronic kidney disease (CKD and identify the related factors.We conducted a community-based cross-sectional study and recruited participants from an area where the residents were exposed to dioxin released from a factory. We defined a "high dioxin level" as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs ≥ 20 pg WHO98-TEQDF/g lipid in the serum and defined CKD as having an estimated glomerular filtration rate (e-GFR ≤ 60 mL/min/1.73m2 or a diagnosis of CKD by a physician. The renal function was assessed between 2005 and 2010, and we excluded those who had had kidney diseases before the study started. Comparisons between patients of CKD and those who did not have CKD were made to identify the risk factors for CKD.Of the 2898 participants, 1427 had high dioxin levels, and 156 had CKD. In the univariate analyses, CKD was associated with high dioxin levels, age, gender, metabolic syndrome, diabetes mellitus, hypertension, and high insulin and uric acid levels. After adjusting for other factors, we found high dioxin levels (adjusted odds ratio [AOR] = 1.76, 95% confidence interval [CI]: 1.04-2.99, female gender (AOR = 1.74, 95%CI: 1.20-2.53, hypertension (AOR = 1.68, 95%CI: 1.17-2.42, high insulin levels (AOR = 2.14, 95% CI: 1.26-3.61, high uric acid levels (AOR = 4.25, 95% CI: 2.92-6.20, and older age (AOR = 4.66, 95% CI: 1.87-11.62 for 40-64 year and AOR = 26.66, 95% CI: 10.51-67.62 for age ≥ 65 year were independent predictors of CKD.A high dioxin level was associated with an increased prevalence of CKD. Therefore, the kidney function of populations with exposure to dioxin should be monitored.

  10. Association between Blood Dioxin Level and Chronic Kidney Disease in an Endemic Area of Exposure.

    Science.gov (United States)

    Huang, Chien-Yuan; Wu, Cheng-Long; Wu, Jin-Shang; Chang, Jung-Wei; Cheng, Ya-Yun; Kuo, Yau-Chang; Yang, Yi-Ching; Lee, Ching-Chang; Guo, How-Ran

    2016-01-01

    Dioxin is an industrial pollutant related to various diseases, but epidemiological data on its effects on the kidney are limited. Therefore, we conducted a study to evaluate the association between dioxin exposure and chronic kidney disease (CKD) and identify the related factors. We conducted a community-based cross-sectional study and recruited participants from an area where the residents were exposed to dioxin released from a factory. We defined a "high dioxin level" as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) ≥ 20 pg WHO98-TEQDF/g lipid in the serum and defined CKD as having an estimated glomerular filtration rate (e-GFR) ≤ 60 mL/min/1.73m2 or a diagnosis of CKD by a physician. The renal function was assessed between 2005 and 2010, and we excluded those who had had kidney diseases before the study started. Comparisons between patients of CKD and those who did not have CKD were made to identify the risk factors for CKD. Of the 2898 participants, 1427 had high dioxin levels, and 156 had CKD. In the univariate analyses, CKD was associated with high dioxin levels, age, gender, metabolic syndrome, diabetes mellitus, hypertension, and high insulin and uric acid levels. After adjusting for other factors, we found high dioxin levels (adjusted odds ratio [AOR] = 1.76, 95% confidence interval [CI]: 1.04-2.99), female gender (AOR = 1.74, 95%CI: 1.20-2.53), hypertension (AOR = 1.68, 95%CI: 1.17-2.42), high insulin levels (AOR = 2.14, 95% CI: 1.26-3.61), high uric acid levels (AOR = 4.25, 95% CI: 2.92-6.20), and older age (AOR = 4.66, 95% CI: 1.87-11.62 for 40-64 year and AOR = 26.66, 95% CI: 10.51-67.62 for age ≥ 65 year) were independent predictors of CKD. A high dioxin level was associated with an increased prevalence of CKD. Therefore, the kidney function of populations with exposure to dioxin should be monitored.

  11. Sound Search Engine Concept

    DEFF Research Database (Denmark)

    2006-01-01

    Sound search is provided by the major search engines, however, indexing is text based, not sound based. We will establish a dedicated sound search services with based on sound feature indexing. The current demo shows the concept of the sound search engine. The first engine will be realased June...

  12. Nightshift work job exposure matrices and urinary 6-sulfatoxymelatonin levels among healthy Chinese women.

    Science.gov (United States)

    Ji, Bu-Tian; Gao, Yu-Tang; Shu, Xiao-Ou; Yang, Gong; Yu, Kai; Xue, Shou-Zheng; Li, Hong-Lan; Liao, Linda M; Blair, Aaron; Rothman, Nathaniel; Zheng, Wei; Chow, Wong-Ho

    2012-11-01

    Six-sulfatoxymelatonin (aMT6s) is a primary urinary metabolite of melatonin. We examined the association between aMT6s levels and shift work estimated by a job exposure matrix (JEM) among healthy participants of the Shanghai Women's Health Study. Creatinine-adjusted aMT6s levels were measured in the urine samples of 300 women and related to JEM shift work categories. Adjusted geometric means of aMT6s levels from urine samples collected before 08:00 hours were lower among persons holding nighttime shift work jobs. The adjusted aMT6s levels (ng/mg creatinine) were 8.36 [95% confidence intervals (95% CI) 4.47-15.6], 6.37 (95% CI 3.53-11.5), 6.20 (95% CI 3.33-11.5), 3.81 (95% CI 2.02-7.19), and 3.70 (95% CI 1.92-7.11) from the lowest (never held a shift work job) to the highest (current job likely involved all-night shift work) shift work JEM scores (P=0.05). Our results indicate that nightshift work JEM scores were significantly and inversely associated with aMT6s levels in early morning spot urine samples collected between 07:00-08:00 hours.

  13. Children exposure to trace levels of heavy metals at the north zone of Kifissos River

    International Nuclear Information System (INIS)

    Evrenoglou, Lefkothea; Partsinevelou, Sofia Aikaterini; Stamatis, Panagiotis; Lazaris, Andreas; Patsouris, Eustratios; Kotampasi, Chrysanthi; Nicolopoulou-Stamati, Polyxeni

    2013-01-01

    This study evaluates the exposure level of primary school children at three different towns in northern Attica, near the banks of the Kifissos River, defining referential values of toxic heavy metals. Concentrations of five toxic metals (arsenic, cadmium, mercury, lead and nickel) were analyzed in water samples from the Kifissos River as well as in the scalp hair of children aged 11 to 12 years old living in the study area. Chronic low-level toxicity of lead and cadmium came into view in recent years as a problem of our civilization. Exposure to concentrations of arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb) poses a potential threat to humans and can cause effects on children's renal and dopaminergic systems without clear evidence of a threshold, a fact that reinforces the need to control all the potential heavy metal emissions into the environment in order to protect children's health. The results were analyzed with the IBM SPSS Statistics 20 for Windows. The possible influence of sex and area was examined. Statistical differences were observed by t-test between the log-transformed hair concentrations of lead (p = 0.021), arsenic (p = 0.016) and nickel (p = 0.038) in children's scalp hair from the municipalities of Kifisia and Kryoneri. ANOVA one-way test confirmed the difference of Pb concentration in hair between girls and boys from the municipality of Kifisia (p = 0.038). The t-test confirms the difference of heavy metal concentrations in river samples between the municipalities Kifisia and Philadelphia in comparison with the samples from Kryoneri. The observations suggest that children living at the municipality of Kifisia are exposed to higher concentrations of heavy metals than the others. Despite all the confounding factors, hair can be used as a biomarker in order to determine the exposure to heavy metals, according to standardized protocols. - Highlights: ► The study area was the north zone of the Kifissos River which is characterized by

  14. Children exposure to trace levels of heavy metals at the north zone of Kifissos River

    Energy Technology Data Exchange (ETDEWEB)

    Evrenoglou, Lefkothea [Department of Sanitary Engineering and Environmental Health, National School of Public Health, 11521 Athens (Greece); Partsinevelou, Sofia Aikaterini, E-mail: partsi@hol.gr [Department of Sanitary Engineering and Environmental Health, National School of Public Health, 11521 Athens (Greece); Stamatis, Panagiotis; Lazaris, Andreas; Patsouris, Eustratios; Kotampasi, Chrysanthi [Department of Pathology, Medical School of Athens,11527 Athens (Greece); Nicolopoulou-Stamati, Polyxeni, E-mail: pnicolopouloustamati@gmail.com [Department of Pathology, Medical School of Athens,11527 Athens (Greece)

    2013-01-15

    This study evaluates the exposure level of primary school children at three different towns in northern Attica, near the banks of the Kifissos River, defining referential values of toxic heavy metals. Concentrations of five toxic metals (arsenic, cadmium, mercury, lead and nickel) were analyzed in water samples from the Kifissos River as well as in the scalp hair of children aged 11 to 12 years old living in the study area. Chronic low-level toxicity of lead and cadmium came into view in recent years as a problem of our civilization. Exposure to concentrations of arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb) poses a potential threat to humans and can cause effects on children's renal and dopaminergic systems without clear evidence of a threshold, a fact that reinforces the need to control all the potential heavy metal emissions into the environment in order to protect children's health. The results were analyzed with the IBM SPSS Statistics 20 for Windows. The possible influence of sex and area was examined. Statistical differences were observed by t-test between the log-transformed hair concentrations of lead (p = 0.021), arsenic (p = 0.016) and nickel (p = 0.038) in children's scalp hair from the municipalities of Kifisia and Kryoneri. ANOVA one-way test confirmed the difference of Pb concentration in hair between girls and boys from the municipality of Kifisia (p = 0.038). The t-test confirms the difference of heavy metal concentrations in river samples between the municipalities Kifisia and Philadelphia in comparison with the samples from Kryoneri. The observations suggest that children living at the municipality of Kifisia are exposed to higher concentrations of heavy metals than the others. Despite all the confounding factors, hair can be used as a biomarker in order to determine the exposure to heavy metals, according to standardized protocols. - Highlights: ► The study area was the north zone of the Kifissos River which is

  15. Levels and patterns of DDTs in maternal colostrum from an island population and exposure of neonates

    International Nuclear Information System (INIS)

    Xu, Chenye; Tang, Mengling; Zhang, Honghui; Zhang, Chunlong; Liu, Weiping

    2016-01-01

    Dichlorodiphenyltrichloroethane (DDT) was heavily used in the past in many regions of the world. The occurrence of DDTs in island populations may be elevated if the island is adjacent to major DDT consumption estuaries, such as the Yangtze River Delta. In this study, colostrum samples were collected from maternal-neonate pairs (n = 106) from the Shengsi Island, located directly downstream from the Yangtze River outlet. DDT isomers and enantiomer compositions were analyzed by gas chromatography equipped with mass spectrometer (GC/MS) and GC/MS-MS. The average levels of p,p’-DDE, o,p’-DDD, p,p’-DDD, o,p’-DDT, p,p’-DDT and total DDTs were 1.32, 0.03, 0.09, 0.08, 0.48, and 1.93  μg g"−"1 lipid weight, respectively. Maternal age and pregnancy body mass index (BMI) were positively associated with levels of DDTs (p < 0.05). High (DDE+DDD)/DDT and p,p′-DDE/p,p′-DDT ratios suggested that current DDT residues originated primarily from historical use of DDT products, but new sources may also contribute partially to some high o,p′-DDT/p,p′-DDT ratios. Enantiomeric enrichment was found for the (−)-enantiomer of o,p’-DDD and the (+)-enantiomer of o,p’-DDT, suggesting stereoselective attenuation. Based on breast milk consumption, the average daily intake of DDTs by neonates was 8.33 ± 7.34 μg kg"−"1bw per day, which exceeded the WHO's tolerable daily intake guideline of 0.01 mg kg"−"1 bw per day by 25%, implying some neonates in the Yangtze River region are potentially at high risk from exposure to DDTs. - Highlights: • DDT isomers and enantiomer compositions were determined by GC/MS and GC/MS–MS. • Maternal age and pregnancy BMI were positively associated with levels of DDTs. • DDT residues was primarily from past technical usage but new sources also existed. • An enrichment was found for (−)-enantiomer of o,p’-DDD and (+)-enantiomer of o,p’-DDT. • Some neonates in this region were potentially at high risk from

  16. Evolution of occupational exposure to environmental levels of aromatic hydrocarbons in service stations.

    Science.gov (United States)

    Periago, J F; Prado, C

    2005-04-01

    During refuelling, people may easily be exposed to extremely high levels of gasoline vapour for a short time, although such exposure takes on more importance in the case of service station attendants. The volume of gasoline sold in refuelling operations and the ambient temperature can significantly increase the environmental level of benzene, toluene and xylene (BTX) vapours and, subsequently, the occupational risk of service station attendants. This is especially true in the case of benzene, the most important component of gasoline vapours from a toxicological point of view. The European Directive 98/70/EC, limiting the benzene composition of gasoline, and 94/63/EC, concerning the use of vapour recovery systems in the delivery of gasoline to services stations, were