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Sample records for solvent exposure measure

  1. Hydrocarbon solvent exposure data: compilation and analysis of the literature.

    Science.gov (United States)

    Caldwell, D J; Armstrong, T W; Barone, N J; Suder, J A; Evans, M J

    2000-01-01

    An occupational exposure database for hydrocarbon solvent end-use applications was constructed from the published literature. The database provides exposure assessment information for such purposes as regulatory risk assessments, support of industry product stewardship initiatives, and identification of applications in which limited exposure data are available. It is quantitative, documented, and based on credible data. Approximately 350 articles containing quantitative hydrocarbon solvent exposure data were identified using a search of computer databases of published literature. Many articles did not report sufficient details of the exposure data for inclusion in the database (e.g., full-shift exposure or task-based exposure data). Others were excluded because only limited summary statistics were provided, which precluded statistical analysis of the data (e.g., arithmetic mean concentration presented, but no sample number). Following evaluation, 16,880 hydrocarbon solvent exposure measurements from 99 articles were entered into a database for analysis. Methods used to identify and evaluate published solvent exposure data are described along with more detailed analysis of worker exposure to hydrocarbon solvents in three major end-use applications: painting and coating, printing, and adhesives. Solvent exposures were evaluated against current ACGIH threshold limit values (TLVs) and trends were identified. Limited quantitative data are available prior to 1970. In general, reported hydrocarbon solvent exposures decreased fourfold from 1960 to 1998, were below the TLVs applicable to specific hydrocarbon solvents at the time, and on average have been below 40% of the TLV since 1980. The database already has proved valuable; however, the utility of published exposure data could be further improved if authors consistently reported essential data elements and supporting information.

  2. Characteristics of peaks of inhalation exposure to organic solvents

    NARCIS (Netherlands)

    Preller, L.; Burstyn, I.; Pater, N. de; Kromhout, H.

    2004-01-01

    Objectives: To determine which exposure metrics are sufficient to characterize 'peak' inhalation exposure to organic solvents (OS) during spraying operations. Methods: Personal exposure measurements (n = 27; duration 5-159 min) were collected during application of paints, primers, resins and glues

  3. Occupational exposure to solvents and bladder cancer

    DEFF Research Database (Denmark)

    Hadkhale, Kishor; Martinsen, Jan Ivar; Weiderpass, Elisabete

    2017-01-01

    logistic regression model was used to estimate hazard ratios (HR) and their 95% confidence intervals (95% CI). Increased risks were observed for trichloroethylene (HR 1.23, 95% 95% CI 1.12-1.40), toluene (HR 1.20, 95% CI 1.00-1.38), benzene (HR 1.16, 95% CI 1.04-1.31), aromatic hydrocarbon solvents (HR 1...... of occupational exposure to trichloroethylene, perchloroethylene, aromatic hydrocarbon solvents, benzene and toluene and the risk of bladder cancer....

  4. Occupational exposure to chlorinated and petroleum solvents and mycosis fungoides

    DEFF Research Database (Denmark)

    Morales-Suárez-Varela, Maria M; Olsen, Jørn; Villeneuve, Sara

    2013-01-01

    To evaluate the potential association between occupational exposure to chlorinated and petroleum solvents and mycosis fungoides (MF).......To evaluate the potential association between occupational exposure to chlorinated and petroleum solvents and mycosis fungoides (MF)....

  5. Exposure Characteristics of Construction Painters to Organic Solvents

    Directory of Open Access Journals (Sweden)

    Hyunhee Park

    2016-03-01

    Conclusion: From this study, we recognized that construction painters are exposed to various solvents, including carcinogens and reproductive toxins, and the levels of TVOC concentration in many of the painting tasks exceeded the exposure limits. Construction workers need to be protected from chemical agents during their painting works by using personal protective devices and/or work practice measures. Additional studies should focus on the exposure assessment of other hazards for construction workers, in order to identify high-risk tasks and to improve hazardous work environments.

  6. Temporal epileptic seizures and occupational exposure to solvents

    DEFF Research Database (Denmark)

    Jacobsen, M; Bælum, Jesper; Bonde, J P

    1994-01-01

    Long term exposure to organic solvents is usually not considered as a possible cause of chronic epileptic seizures. A case that shows a remarkable coincidence between exposure to organic solvents and occurrence of epileptic seizures is reported. The man was a 58 year old sign writer with lifelong...

  7. Occupational exposure to organic solvents and sleep-disordered breathing.

    Science.gov (United States)

    Ulfberg, J; Carter, N; Talbäck, M; Edling, C

    1997-01-01

    To investigate whether people with occupational exposure to organic solvents have a higher prevalence of obstructive sleep apnea syndrome (OSAS) than the general population and to examine the relationship between snoring and exposure to organic solvents. Consecutive patients, aged 30-64 years, referred during a 3-year period to the sleep laboratory at Avesta Hospital, Sweden, because of suspected OSAS made up the patient groups. Following admission, patients underwent a simplified sleep apnea investigation and were divided into two groups, OSAS (n = 320) and snorers (n = 443). A random sample of 296 men and 289 women aged 30-64 years obtained from a register of all country residents maintained by the county tax authority served as referents (controls). Both patients and referents responded to two questionnaires, including questions about occupation, exposure to organic solvents, and other chemical and physical agents. Men with OSAS or snoring and women with snoring had more often been occupationally exposed to organic solvents than the referents, showing an almost twofold increase in risk for those exposed during whole workdays. For men, the risk of OSAS or snoring increased with increasing exposure. The result indicates that occupational exposure to organic solvents might cause sleep apnea. A new observation is that even snoring could be caused by exposure to organic solvents. It is important to elucidate whether exposure to organic solvents is a cause of OSAS, because such a finding may have important implications for prevention and treatment of sleep disturbances.

  8. Effect of Exposure to a Mixture of Organic Solvents on Hearing Thresholds in Petrochemical Industry Workers

    Directory of Open Access Journals (Sweden)

    Ziba Loukzadeh

    2014-10-01

    Full Text Available Introduction: Hearing loss is one of the most common occupational diseases. In most workplaces, workers are exposed to noise and solvents simultaneously, so the potential risk of hearing loss due to solvents may be attributed to noise.  In this study we aimed to assess the effect of exposure to mixed aromatic solvents on hearing in the absence of exposure to hazardous noise.   Materials and Methods: In a cross-sectional study, 99 workers from the petrochemical industry with exposure to a mixture of organic solvents whose noise exposure was lower than 85 dBA were compared with 100 un-exposed controls. After measuring sound pressure level and mean concentration of each solvent in the workplace, pure-tone-audiometry was performed and the two groups were compared in terms of high-frequency and low-frequency hearing loss. T-tests and Chi-square tests were used to compare the two groups.   Results: The mean hearing threshold at all frequencies among petrochemical workers was normal (below 25 dB. We did not observe any significant association between solvent exposure and high-frequency or low-frequency hearing loss.   Conclusion:  This study showed that temporary exposure (less than 4 years to a mixture of organic solvents, without exposure to noise, does not affect workers’ hearing threshold in audiometry tests.

  9. Effect of exposure to a mixture of organic solvents on hearing thresholds in petrochemical industry workers.

    Science.gov (United States)

    Loukzadeh, Ziba; Shojaoddiny-Ardekani, Ahmad; Mehrparvar, Amir Houshang; Yazdi, Zohreh; Mollasadeghi, Abolfazl

    2014-10-01

    Hearing loss is one of the most common occupational diseases. In most workplaces, workers are exposed to noise and solvents simultaneously, so the potential risk of hearing loss due to solvents may be attributed to noise. In this study we aimed to assess the effect of exposure to mixed aromatic solvents on hearing in the absence of exposure to hazardous noise. In a cross-sectional study, 99 workers from the petrochemical industry with exposure to a mixture of organic solvents whose noise exposure was lower than 85 dBA were compared with 100 un-exposed controls. After measuring sound pressure level and mean concentration of each solvent in the workplace, pure-tone-audiometry was performed and the two groups were compared in terms of high-frequency and low-frequency hearing loss. T-tests and Chi-square tests were used to compare the two groups. The mean hearing threshold at all frequencies among petrochemical workers was normal (below 25 dB). We did not observe any significant association between solvent exposure and high-frequency or low-frequency hearing loss. This study showed that temporary exposure (less than 4 years) to a mixture of organic solvents, without exposure to noise, does not affect workers' hearing threshold in audiometry tests.

  10. Measuring solvent barrier properties of paper

    International Nuclear Information System (INIS)

    Bollström, Roger; Saarinen, Jarkko J; Toivakka, Martti; Räty, Jukka

    2012-01-01

    New methods for measuring barrier properties against solvents, acids and bases on dispersion coated paper were developed and investigated. Usability, reliability and repeatability were compared both between the new methods and with the standardized method for measuring barrier properties against water vapor. Barrier properties could be measured with all methods and the results obtained by the different methods were in correlation with each other. A qualitative method based on a trace color provided an indicative result, whereas further developed methods also took into account the durability. The effective barrier lifetime could be measured by measuring the conductivity through the substrate as a function of time, or by utilizing a glass prism where the change in refractive index caused by penetrated liquid was monitored, also as a function of time. Barrier properties against water and humidity were also measured and were found not to be predictors for barrier properties against either solvents, or acids or bases, which supports the need to develop new methods

  11. Occupational exposure to solvents and acute myeloid leukemia

    DEFF Research Database (Denmark)

    Talibov, Madar; Lehtinen-Jacks, Susanna; Martinsen, Jan Ivar

    2014-01-01

    OBJECTIVE: The aim of the current study was to assess the relation between occupational exposure to solvents and the risk of acute myeloid leukemia (AML). METHODS: Altogether, this study comprises 15 332 incident cases of AML diagnosed in Finland, Norway, Sweden and Iceland from 1961-2005 and 76...

  12. Exposure to pesticides or solvents and risk of Parkinson disease.

    Science.gov (United States)

    Pezzoli, Gianni; Cereda, Emanuele

    2013-05-28

    To investigate the risk of Parkinson disease (PD) associated with exposure to pesticides and solvents using meta-analyses of data from cohort and case-control studies. Prospective cohort and case-control studies providing risk and precision estimates relating PD to exposure to pesticides or solvents or to proxies of exposure were considered eligible. The heterogeneity in risk estimates associated with objective study quality was also investigated. A total of 104 studies/3,087 citations fulfilled inclusion criteria for meta-analysis. In prospective studies, study quality was not a source of heterogeneity. PD was associated with farming and the association with pesticides was highly significant in the studies in which PD diagnosis was self-reported. In case-control studies, study quality appeared to be a source of heterogeneity in risk estimates for some exposures. Higher study quality was frequently associated with a reduction in heterogeneity. In high-quality case-control studies, PD risk was increased by exposure to any-type pesticides, herbicides, and solvents. Exposure to paraquat or maneb/mancozeb was associated with about a 2-fold increase in risk. In high-quality case-control studies including an appreciable number of cases (>200), heterogeneity remained significantly high (>40%) only for insecticides, organochlorines, organophosphates, and farming; also, the risk associated with rural living was found to be significant. The literature supports the hypothesis that exposure to pesticides or solvents is a risk factor for PD. Further prospective and high-quality case-control studies are required to substantiate a cause-effect relationship. The studies should also focus on specific chemical agents.

  13. Psychiatric symptomatology in persons with organic solvent exposure.

    Science.gov (United States)

    Morrow, L A; Kamis, H; Hodgson, M J

    1993-02-01

    This study investigated psychiatric symptomatology, self-concept, locus of control, and daily events in persons with a history of exposure to mixtures of organic solvents. Exposed subjects were more likely than controls to report depression, anxiety, fatigue, confusion, and somatic concerns, which in turn were associated with certain exposure-related variables (e.g., cacosmia). There were no differences between the groups in self-concept, locus of control, or ratings of daily hassles and uplifts. Exposed persons may be able to accurately identify what they perceive as changes that are due to the exposure (e.g., anxiety) without attributing these specific adverse outcomes to dispositional variables.

  14. Organic solvent exposure and contrast sensitivity: comparing men and women

    Science.gov (United States)

    Oliveira, A.R.; Campos, A.A.; de Andrade, M.J.O.; de Medeiros, P.C.B.; dos Santos, N.A.

    2018-01-01

    The goal of this study was to compare the visual contrast sensitivity (CS) of men and women exposed and not exposed to organic solvents. Forty-six volunteers of both genders aged between 18 and 41 years (mean±SD=27.72±6.28) participated. Gas station attendants were exposed to gas containing 46.30 ppm of solvents at a temperature of 304±274.39 K, humidity of 62.25±7.59% and ventilation of 0.69±0.46 m/s (a passive gas chromatography-based sampling method was used considering the microclimate variables). Visual CS was measured via the psychophysical method of two-alternative forced choice using vertical sinusoidal gratings with spatial frequencies of 0.2, 0.5, 1.0, 2.0, 5.0, 10.0, and 16.0 cpd (cycles per degree) and an average luminance of 34.4 cd/m2. The results showed that visual CS was significantly lower (P<0.05) in the following groups: i) exposed men compared to unexposed men at frequencies of 0.2, 0.5, 1.0, and 2.0 cpd; ii) exposed women compared to unexposed women at a frequency of 5.0 cpd; and iii) exposed women compared to exposed men at a frequency of 0.5 cpd, even at exposures below the tolerance limit (300 ppm). These results suggest that the visual CS of exposed men was impaired over a wider range of spatial frequencies than that of exposed women. This difference may have been due to the higher body fat content of women compared to that of men, suggesting that body fat in women can serve as a protective factor against neurotoxic effects. PMID:29340521

  15. Exposure to organic solvents in the offset printing industry in Norway.

    Science.gov (United States)

    Svendsen, K; Rognes, K S

    2000-03-01

    The purpose of this study was to document the conditions regarding solvent exposure at offset printing offices in Norway at present and to study the variation of exposure between printing office technologies. Measurements were made at seven offset printing offices. The measurements consisted of five to 10 whole day personal exposure measurements at each office performed over a period of 2 months. Variables that may influence the level of exposure were registered by the occupational hygienist at the end of each measuring day using a check list. The influence of the variables on the "additive factor" was examined by linear regression analysis.The main contributor to the "additive factor" was isopropanol. The exposure to isopropanol sometimes exceeded the Norwegian TLV. The exposure decreased when a separate exhaust ventilation was used. The exposure increased when the machine had automatic cleaning. The variables automatic cleaning and separate exhaust ventilation explained 59% of the variation in the "additive factor". The results of this study indicate that the most important source of solvent exposure in printing offices at present is the moisturizer used in the printing machines. We think it is worth giving attention to this exposure and making efforts to reduce it.

  16. Measurement of oxygen transfer from air into organic solvents

    DEFF Research Database (Denmark)

    Ramesh, Hemalata; Mayr, Torsten; Hobisch, Mathias

    2016-01-01

    biological reactions require the supply of oxygen, most normally from air. However, reliable on-line measurements of oxygen concentration in organic solvents (and hence oxygen transfer rates from air to the solvent) has to date proven impossible due limitations in the current analytical methods. Results...... applications). Subsequently, we measured the oxygen transfer rates from air into these organic solvents. Conclusion The measurement of oxygen transfer rates from air into organic solvents using the dynamic method was established using the solvent resistant optical sensor. The feasibility of online oxygen...... For the first time, we demonstrate on-line oxygen measurements in non-aqueous media using a novel optical sensor. The sensor was used to measure oxygen concentration in various organic solvents including toluene, THF, isooctane, DMF, heptane and hexane (which have all been shown suitable for several biological...

  17. Renal effects of chronic exposure to organic solvents. A clinical controlled trial

    Energy Technology Data Exchange (ETDEWEB)

    Krusell, L.; Nielsen, H.K.; Baelum, J.; Lundqvist, G.; Omland, O.; Vaeth, M.; Husted, S.E.; Mogensen, C.E.; Geday, E.

    1985-01-01

    Chronic effects of organic solvents on renal function were measured by creatinine clearances and urinary excretion rates of beta 2-microglobulin and albumin. Forty-three male printing trade workers occupationally exposed to different organic solvents for 9-25 years were compared with 43 age-matched male controls. No differences were found either in creatinine clearances or average basal levels of beta 2-microglobulin and albumin excretion rates, whereas a positive relation could be demonstrated between alcohol consumption on the day before the trial and urinary excretion rate of albumin. This investigation did not reveal any adverse renal effects of moderate chronic exposure to organic solvents in a group of active trade workers.

  18. Renal effects of chronic exposure to organic solvents. A clinical controlled trial

    DEFF Research Database (Denmark)

    Krusell, Lars Romer; Nielsen, H K; Bælum, Jesper

    1985-01-01

    Chronic effects of organic solvents on renal function were measured by creatinine clearances and urinary excretion rates of beta 2-microglobulin and albumin. Forty-three male printing trade workers occupationally exposed to different organic solvents for 9-25 years were compared with 43 age......-matched male controls. No differences were found either in creatinine clearances or average basal levels of beta 2-microglobulin and albumin excretion rates, whereas a positive relation could be demonstrated between alcohol consumption on the day before the trial and urinary excretion rate of albumin....... This investigation did not reveal any adverse renal effects of moderate chronic exposure to organic solvents in a group of active trade workers....

  19. Measurement and correlation of solubility of cefmenoxime hydrochloride in pure solvents and binary solvent mixtures

    International Nuclear Information System (INIS)

    Wang, Jinxiu; Xie, Chuang; Yin, Qiuxiang; Tao, Linggang; Lv, Jun; Wang, Yongli; He, Fang; Hao, Hongxun

    2016-01-01

    Highlights: • Solubility of cefmenoxime hydrochloride in pure and binary solvents was determined. • The experimental solubility data were correlated by thermodynamic models. • A model was employed to calculate the melting temperature of cefmenoxime hydrochloride. • Mixing thermodynamic properties of cefmenoxime hydrochloride were calculated. - Abstract: The solubility of cefmenoxime hydrochloride in pure solvents and binary solvent mixtures was measured at temperatures from (283.15 to 313.15) K by using the UV spectroscopic method. The results reveal that the solubility of cefmenoxime hydrochloride increases with increasing temperature in all solvent selected. The solubility of cefmenoxime hydrochloride reaches its maximum value when the mole fraction of isopropanol is 0.2 in the binary solvent mixtures of (isopropanol + water). The modified Apelblat equation and the NRTL model were successfully used to correlate the experimental solubility in pure solvents while the modified Apelblat equation, the CNIBS/R–K model and the Jouyban–Acree model were applied to correlate the solubility in binary solvent mixtures. In addition, the mixing thermodynamic properties of cefmenoxime hydrochloride in different solvents were also calculated based on the NRTL model and experimental solubility data.

  20. Organic solvent exposure and depressive symptoms among licensed pesticide applicators in the Agricultural Health Study.

    Science.gov (United States)

    Siegel, Miriam; Starks, Sarah E; Sanderson, Wayne T; Kamel, Freya; Hoppin, Jane A; Gerr, Fred

    2017-11-01

    Although organic solvents are often used in agricultural operations, neurotoxic effects of solvent exposure have not been extensively studied among farmers. The current analysis examined associations between questionnaire-based metrics of organic solvent exposure and depressive symptoms among farmers. Results from 692 male Agricultural Health Study participants were analyzed. Solvent type and exposure duration were assessed by questionnaire. An "ever-use" variable and years of use categories were constructed for exposure to gasoline, paint/lacquer thinner, petroleum distillates, and any solvent. Depressive symptoms were ascertained with the Center for Epidemiologic Studies Depression Scale (CES-D); scores were analyzed separately as continuous (0-60) and dichotomous (distillates, and short duration of petroleum distillate exposure and continuous CES-D score (p < 0.05). Although nearly all associations were positive, fewer statistically significant associations were observed between metrics of solvent exposure and the dichotomized CES-D variable. Solvent exposures were associated with depressive symptoms among farmers. Efforts to limit exposure to organic solvents may reduce the risk of depressive symptoms among farmers.

  1. Noise-induced hearing loss in Korean workers: co-exposure to organic solvents and heavy metals in nationwide industries.

    Directory of Open Access Journals (Sweden)

    Yoon-Hyeong Choi

    Full Text Available BACKGROUND: Noise exposure is a well-known contributor to work-related hearing loss. Recent biological evidence suggests that exposure to ototoxic chemicals such as organic solvents and heavy metals may be additional contributors to hearing loss. However, in industrial settings, it is difficult to determine the risks of hearing loss due to these chemicals in workplaces accompanied by excessive noise exposure. A few studies suggest that the effect of noise may be enhanced by ototoxic chemicals. Therefore, this study investigated whether co-exposure to organic solvents and/or heavy metals in the workplace modifies the risk of noise exposure on hearing loss in a background of excessive noise. METHODS: We examined 30,072 workers nationwide in a wide range of industries from the Korea National Occupational Health Surveillance 2009. Data on industry-based exposure (e.g., occupational noise, heavy metals, and organic solvents and subject-specific health outcomes (e.g., audiometric examination were collected. Noise was measured as the daily 8-h time-weighted average level. Air conduction hearing thresholds were measured from 0.5 to 6 kHz, and pure-tone averages (PTA (i.e., means of 2, 3, and 4 kHz were computed. RESULTS: In the multivariate linear model, PTA increment with occupational noise were 1.64-fold and 2.15-fold higher in individuals exposed to heavy metals and organic solvents than in unexposed individuals, respectively. CONCLUSION: This study provides nationwide evidence that co-exposure to heavy metals and/or organic solvents may exacerbate the effect of noise exposure on hearing loss in workplaces. These findings suggest that workers in industries dealing with heavy metals or organic solvents are susceptible to such risks.

  2. Noise-induced hearing loss in Korean workers: co-exposure to organic solvents and heavy metals in nationwide industries.

    Science.gov (United States)

    Choi, Yoon-Hyeong; Kim, KyooSang

    2014-01-01

    Noise exposure is a well-known contributor to work-related hearing loss. Recent biological evidence suggests that exposure to ototoxic chemicals such as organic solvents and heavy metals may be additional contributors to hearing loss. However, in industrial settings, it is difficult to determine the risks of hearing loss due to these chemicals in workplaces accompanied by excessive noise exposure. A few studies suggest that the effect of noise may be enhanced by ototoxic chemicals. Therefore, this study investigated whether co-exposure to organic solvents and/or heavy metals in the workplace modifies the risk of noise exposure on hearing loss in a background of excessive noise. We examined 30,072 workers nationwide in a wide range of industries from the Korea National Occupational Health Surveillance 2009. Data on industry-based exposure (e.g., occupational noise, heavy metals, and organic solvents) and subject-specific health outcomes (e.g., audiometric examination) were collected. Noise was measured as the daily 8-h time-weighted average level. Air conduction hearing thresholds were measured from 0.5 to 6 kHz, and pure-tone averages (PTA) (i.e., means of 2, 3, and 4 kHz) were computed. In the multivariate linear model, PTA increment with occupational noise were 1.64-fold and 2.15-fold higher in individuals exposed to heavy metals and organic solvents than in unexposed individuals, respectively. This study provides nationwide evidence that co-exposure to heavy metals and/or organic solvents may exacerbate the effect of noise exposure on hearing loss in workplaces. These findings suggest that workers in industries dealing with heavy metals or organic solvents are susceptible to such risks.

  3. Noise-Induced Hearing Loss in Korean Workers: Co-Exposure to Organic Solvents and Heavy Metals in Nationwide Industries

    Science.gov (United States)

    Choi, Yoon-Hyeong; Kim, KyooSang

    2014-01-01

    Background Noise exposure is a well-known contributor to work-related hearing loss. Recent biological evidence suggests that exposure to ototoxic chemicals such as organic solvents and heavy metals may be additional contributors to hearing loss. However, in industrial settings, it is difficult to determine the risks of hearing loss due to these chemicals in workplaces accompanied by excessive noise exposure. A few studies suggest that the effect of noise may be enhanced by ototoxic chemicals. Therefore, this study investigated whether co-exposure to organic solvents and/or heavy metals in the workplace modifies the risk of noise exposure on hearing loss in a background of excessive noise. Methods We examined 30,072 workers nationwide in a wide range of industries from the Korea National Occupational Health Surveillance 2009. Data on industry-based exposure (e.g., occupational noise, heavy metals, and organic solvents) and subject-specific health outcomes (e.g., audiometric examination) were collected. Noise was measured as the daily 8-h time-weighted average level. Air conduction hearing thresholds were measured from 0.5 to 6 kHz, and pure-tone averages (PTA) (i.e., means of 2, 3, and 4 kHz) were computed. Results In the multivariate linear model, PTA increment with occupational noise were 1.64-fold and 2.15-fold higher in individuals exposed to heavy metals and organic solvents than in unexposed individuals, respectively. Conclusion This study provides nationwide evidence that co-exposure to heavy metals and/or organic solvents may exacerbate the effect of noise exposure on hearing loss in workplaces. These findings suggest that workers in industries dealing with heavy metals or organic solvents are susceptible to such risks. PMID:24870407

  4. Response of solvent-exposed printers and unexposed controls to six-hour toluene exposure

    DEFF Research Database (Denmark)

    Bælum, Jesper; Andersen, I B; Lundqvist, G R

    1985-01-01

    of intoxication, and irritation of the eyes, nose and throat. Furthermore, the subjects exposed to toluene showed decreased manual dexterity, decreased color discrimination, and decreased accuracy in visual perception. There was no significant difference in the effects of toluene on printers compared to those......The acute effects of toluene were studied in 43 male printers and 43 control subjects matched according to sex, age, educational level, and smoking habits. The mean age of the subjects was 36 (range 29-50) years. The printers had been exposed to solvents for 9 to 25 years during employment at flexo...... and rotogravure printing plants, while the controls had no history of solvent exposure. Each subject was exposed once in a climate chamber to either 100 ppm of toluene or clean air for 6.5 h preceded by a 1-h acclimatization period. The effects of toluene were measured from subjective votes with linear analogue...

  5. Exposure to fingers while handling a solvent extraction-type technetium-99m generator

    International Nuclear Information System (INIS)

    Kini, K.S.; Venkateswaran, T.V.

    1985-01-01

    Technetium-99m-labeled compounds are routinely used for various diagnostic procedures in nuclear medicine. In India, most of the nuclear medicine centers use /sup 99m/Tc obtained from a solvent extraction-type generator. As a result of the long procedure involved in the separation of /sup 99m/Tc from /sup 99m/Mo in this type of generator compared to the elution of /sup 99m/Tc from a column-type generator, like likelihood of exposure to fingers of technicians is high. The measurement of radiation exposure was done on 16 workers at seven major nuclear medicine centers in India. With the existing work load, the exposures to the fingers were found to be within the permissible limits

  6. Assessment of Relationship between Spontaneous Abortion and Occupational Exposure to Organic Solvents

    Directory of Open Access Journals (Sweden)

    S Mohammadi

    2011-04-01

    Full Text Available Introduction & Objective: Nowadays, some studies indicate the adverse effects of exposure to chemicals, especially organic solvents on the reproductive system of females. This study aimed to assess the relationship between spontaneous abortion with occupational exposure to organic solvents in pharmaceutical industry. Materials & Methods: This is a cross-sectional and descriptive-analytical study which was carried out in 2010 in one of the pharmaceutical factories located in the suburbs of Tehran. During the study, married women who were working in the factory laboratory units and were exposed to mixed organic solvents were compared with married women who were working in the packing units of the factory without occupational exposure to organic solvents. Frequency of spontaneous abortion and duration of pregnancy were assessed in both two groups. Collected data were analyzed with the SPSS software using t-test, logistic regression, and chi-square test. Results: In the present study, the frequency of spontaneous abortion in employees with exposure to organic solvents mixture was 10.7%. This study showed that even after adjustment for confounding factors, there was a significant correlation between spontaneous abortion and occupational exposure to organic solvents mixture and this correlation increased with increasing levels of exposure to organic solvents. Moreover, a significant correlation was observed between occupational exposure to mixed organic solvents and waiting time to become pregnant (TTP. Furthermore, this study showed that even after adjustment for confounding variables, shift workers were significantly more affected by spontaneous abortion compared to daytime workers (P < 0.001. Conclusion: According to the results of this study, since there is probability of spontaneous abortion resulting from occupational exposure to various chemicals including organic solvents, review of the status of occupational exposure of workers can be helpful

  7. Chronic Organic Solvent Exposure Changes Visual Tracking in Men and Women

    Directory of Open Access Journals (Sweden)

    Ana R. de Oliveira

    2017-11-01

    Full Text Available Organic solvents can change CNS sensory and motor function. Eye-movement analyses can be important tools when investigating the neurotoxic changes that result from chronic organic solvent exposure. The current research measured the eye-movement patterns of men and women with and without histories of chronic organic solvent exposure. A total of 44 volunteers between 18 and 41 years old participated in this study; 22 were men (11 exposed and 11 controls, and 22 were women (11 exposed and 11 controls. Eye movement was evaluated using a 250-Hz High-Speed Video Eye Tracker Toolbox (Cambridge Research Systems via an image of a maze. Specific body indices of exposed and non-exposed men and women were measured with an Inbody 720 to determine whether the differences in eye-movement patterns were associated with body composition. The data were analyzed using IBM SPSS Statistics version 20.0.0. The results indicated that exposed adults showed significantly more fixations (t = 3.82; p = 0.001; r = 0.51 and longer fixations (t = 4.27; p = 0.001, r = 0.54 than their non-exposed counterparts. Comparisons within men (e.g., exposed and non-exposed showed significant differences in the number of fixations (t = 2.21; p = 0.04; r = 0.20 and duration of fixations (t = 3.29; p = 0.001; r = 0.35. The same was true for exposed vs. non-exposed women, who showed significant differences in the number of fixations (t = 3.10; p = 0.001; r = 0.32 and fixation durations (t = 2.76; p = 0.01; r = 0.28. However, the results did not show significant differences between exposed women and men in the number and duration of fixations. No correlations were found between eye-movement pattern and body composition measures (p > 0.05. These results suggest that chronic organic solvent exposure affects eye movements, regardless of sex and body composition, and that eye tracking contributes to the investigation of the visual information processing disorders acquired by workers exposed to

  8. Chronic Organic Solvent Exposure Changes Visual Tracking in Men and Women.

    Science.gov (United States)

    de Oliveira, Ana R; Campos Neto, Armindo de Arruda; Bezerra de Medeiros, Paloma C; de Andrade, Michael J O; Dos Santos, Natanael A

    2017-01-01

    Organic solvents can change CNS sensory and motor function. Eye-movement analyses can be important tools when investigating the neurotoxic changes that result from chronic organic solvent exposure. The current research measured the eye-movement patterns of men and women with and without histories of chronic organic solvent exposure. A total of 44 volunteers between 18 and 41 years old participated in this study; 22 were men (11 exposed and 11 controls), and 22 were women (11 exposed and 11 controls). Eye movement was evaluated using a 250-Hz High-Speed Video Eye Tracker Toolbox (Cambridge Research Systems) via an image of a maze. Specific body indices of exposed and non-exposed men and women were measured with an Inbody 720 to determine whether the differences in eye-movement patterns were associated with body composition. The data were analyzed using IBM SPSS Statistics version 20.0.0. The results indicated that exposed adults showed significantly more fixations ( t = 3.82; p = 0.001; r = 0.51) and longer fixations ( t = 4.27; p = 0.001, r = 0.54) than their non-exposed counterparts. Comparisons within men (e.g., exposed and non-exposed) showed significant differences in the number of fixations ( t = 2.21; p = 0.04; r = 0.20) and duration of fixations ( t = 3.29; p = 0.001; r = 0.35). The same was true for exposed vs. non-exposed women, who showed significant differences in the number of fixations ( t = 3.10; p = 0.001; r = 0.32) and fixation durations ( t = 2.76; p = 0.01; r = 0.28). However, the results did not show significant differences between exposed women and men in the number and duration of fixations. No correlations were found between eye-movement pattern and body composition measures ( p > 0.05). These results suggest that chronic organic solvent exposure affects eye movements, regardless of sex and body composition, and that eye tracking contributes to the investigation of the visual information processing disorders acquired by workers exposed to

  9. Acute behavioral effects of exposure to some organic solvents -psychophysiological aspects

    Energy Technology Data Exchange (ETDEWEB)

    Winneke, G

    1982-01-01

    Acute low-level exposure to organic solvent vapours may result in prenarcotic states of CNS-depression, often characterized by behavioral dysfunction. Behavioral findings from experimental acute human exposures to toluene, trichloroethylene (TCE), and methylene chloride (MC) are covered in this review. Perceptual measures (e.g. critical flicker fusion . CFF), measures of sustained attention (vigilance), measures of psychomotor performance (as e.g. reaction time, motor speed, coordination) as well as EEG-measures (sensory evoked potentials) are used to illustrate the main effects from such studies. Progressive increase of reaction time was observed at toluene-exposures of only 300 ppm (30 minutes). No consistent behavioral deficit has been reported for trichloroethylene below 300 ppm; instead, visual and auditory evoked potentials were found to be affected at TCE vapour-concentrations between 50 and 100 ppm (3 1/2 - 7 1/2 hours of exposure). CFF-depression, vigilance-decrement and disruption of psychomotor performance has been observed during MC-exposure (200 - 800 ppm; 2-4 hours). Although such behavioral effects are usually considered reversible and of no demonstrated pathological impact, they may nevertheless contribute to accident-prone behavior in occupational settings.

  10. Occupational exposure to solvents, metals and welding fumes and risk of Parkinson's disease.

    Science.gov (United States)

    van der Mark, Marianne; Vermeulen, Roel; Nijssen, Peter C G; Mulleners, Wim M; Sas, Antonetta M G; van Laar, Teus; Huss, Anke; Kromhout, Hans

    2015-06-01

    The aim of this study was to investigate the potential association between occupational exposure to solvents, metals and/or welding fumes and risk of developing Parkinson's disease (PD). Data of a hospital based case-control study including 444 PD patients and 876 age and sex matched controls was used. Occupational histories and lifestyle information of cases and controls were collected in a structured telephone interview. Exposures to aromatic solvents, chlorinated solvents and metals were estimated by linking the ALOHA+ job-exposure matrix to the occupational histories. Exposure to welding fumes was estimated using self-reported information on welding activities. No statistically significant associations with any of the studied metal and solvent exposures were found. However, for self-reported welding activities we observed non-statistically significant reduced risk estimates (third tertile cumulative exposure: OR = 0.51 (95% CI: 0.21-1.24)). The results of our study did not provide support for an increased chance on developing PD after occupational exposure to aromatic solvents, chlorinated solvents or exposure to metals. The results showed reduced risk estimates for welding, which is in line with previous research, but no clear explanation for these findings is available. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Non-Hodgkin's lymphoma risk derived from exposure to organic solvents: a review of epidemiologic studies

    Directory of Open Access Journals (Sweden)

    Rêgo Marco Antônio V.

    1998-01-01

    Full Text Available The rate of non-Hodgkin's lymphomas (NHL has increased around the world during the last decades. Apart from the role of the human immunodeficiency virus (HIV infection in the development of NHL, exposure to chemical agents like phenoxyacetic pesticides, hair dyes, metal fumes and organic solvents are suspected to be involved. The present review evaluates the results of studies that directly or indirectly searched for an association between solvent exposure and NHL. The selected studies comprised those published from 1979 to 1997, designed to investigate risk factors for NHL, whether specifically looking for solvent exposure or for general risks in which solvent exposure could be included. In 25 of the 45 reviewed studies (55.5%, fifty-four statistically significant associations between NHL and solvent exposure related occupations or industries were reported. Statistical significance was more frequently shown in studies where solvent exposure was more accurately defined. In eighteen of such studies, 13 (72.2% defined or suggested organic solvents as possible risk factors for NHL.

  12. Non-Hodgkin's lymphoma risk derived from exposure to organic solvents: a review of epidemiologic studies

    Directory of Open Access Journals (Sweden)

    Marco Antônio V. Rêgo

    Full Text Available The rate of non-Hodgkin's lymphomas (NHL has increased around the world during the last decades. Apart from the role of the human immunodeficiency virus (HIV infection in the development of NHL, exposure to chemical agents like phenoxyacetic pesticides, hair dyes, metal fumes and organic solvents are suspected to be involved. The present review evaluates the results of studies that directly or indirectly searched for an association between solvent exposure and NHL. The selected studies comprised those published from 1979 to 1997, designed to investigate risk factors for NHL, whether specifically looking for solvent exposure or for general risks in which solvent exposure could be included. In 25 of the 45 reviewed studies (55.5%, fifty-four statistically significant associations between NHL and solvent exposure related occupations or industries were reported. Statistical significance was more frequently shown in studies where solvent exposure was more accurately defined. In eighteen of such studies, 13 (72.2% defined or suggested organic solvents as possible risk factors for NHL.

  13. ESTIMATED RATE OF FATAL AUTOMOBILE ACCIDENTS ATTRIBUTABLE TO ACUTE SOLVENT EXPOSURE AT LOW INHALED CONCENTRATIONS

    Science.gov (United States)

    Acute solvent exposures may contribute to automobile accidents because they increase reaction time and decrease attention, in addition to impairing other behaviors. These effects resemble those of ethanol consumption, both with respect to behavioral effects and neurological mecha...

  14. A comparison of the effects of solvent and noise exposure on hearing, together and separately

    Directory of Open Access Journals (Sweden)

    Ilhan Unlu

    2014-01-01

    Full Text Available The objective of the present study was to assess the effects of occupational exposure to noise and organic solvents on hearing loss in bus and truck plant workers. Our case control study contained 469 workers from a bus and truck plant divided into three groups. The first group contained workers exposed to only noise; the second group contained workers exposed to both noise and mixture solvents at a permissible level; and the third group included workers exposed to permissible levels of solvents. The control group (Group 4 included 119 individuals selected randomly, persons who were not exposed to noise and solvents. These groups were compared in terms of each individual′s frequency hearing loss in both ears. Our study demonstrates that combined exposure to mixed solvents and noise can exacerbate hearing loss in workers. Hence, a suitable hearing protection program is advised that would contain short-interval audiometric examinations and efficient hearing protectors.

  15. Exposure to organic solvents used in dry cleaning reduces low and high level visual function.

    Directory of Open Access Journals (Sweden)

    Ingrid Astrid Jiménez Barbosa

    Full Text Available To investigate whether exposure to occupational levels of organic solvents in the dry cleaning industry is associated with neurotoxic symptoms and visual deficits in the perception of basic visual features such as luminance contrast and colour, higher level processing of global motion and form (Experiment 1, and cognitive function as measured in a visual search task (Experiment 2.The Q16 neurotoxic questionnaire, a commonly used measure of neurotoxicity (by the World Health Organization, was administered to assess the neurotoxic status of a group of 33 dry cleaners exposed to occupational levels of organic solvents (OS and 35 age-matched non dry-cleaners who had never worked in the dry cleaning industry. In Experiment 1, to assess visual function, contrast sensitivity, colour/hue discrimination (Munsell Hue 100 test, global motion and form thresholds were assessed using computerised psychophysical tests. Sensitivity to global motion or form structure was quantified by varying the pattern coherence of global dot motion (GDM and Glass pattern (oriented dot pairs respectively (i.e., the percentage of dots/dot pairs that contribute to the perception of global structure. In Experiment 2, a letter visual-search task was used to measure reaction times (as a function of the number of elements: 4, 8, 16, 32, 64 and 100 in both parallel and serial search conditions.Dry cleaners exposed to organic solvents had significantly higher scores on the Q16 compared to non dry-cleaners indicating that dry cleaners experienced more neurotoxic symptoms on average. The contrast sensitivity function for dry cleaners was significantly lower at all spatial frequencies relative to non dry-cleaners, which is consistent with previous studies. Poorer colour discrimination performance was also noted in dry cleaners than non dry-cleaners, particularly along the blue/yellow axis. In a new finding, we report that global form and motion thresholds for dry cleaners were also

  16. Human solvent exposure. Factors influencing the pharmacokinetics and acute toxicity

    DEFF Research Database (Denmark)

    Bælum, Jesper

    1991-01-01

    visual perception, colour vision, vigilance as well as the psychomotor functions. However, the influence on the performance tests was not seen in all studies. Variations in the air concentration of toluene with peaks op to 300 ppm causes fluctuation in the alveolar concentrations, but no acute effect...... of printers occupationally exposed to mixtures of solvents were compared with a matched unexposed control group. There was no difference between printers and controls in the performance in the psychological test, but in two of the tests there were tendencies to increased sensitivity to toluene in the group...

  17. Auditory Effects of Exposure to Noise and Solvents: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Lobato, Diolen Conceição Barros

    2014-01-01

    Full Text Available Introduction Industry workers are exposed to different environmental risk agents that, when combined, may potentiate risks to hearing. Objective To evaluate the effects of the combined exposure to noise and solvents on hearing in workers. Methods A transversal retrospective cohort study was performed through documentary analysis of an industry. The sample (n = 198 was divided into four groups: the noise group (NG, exposed only to noise; the noise and solvents group (NSG, exposed to noise and solvents; the noise control group and noise and solvents control group (CNS, no exposure. Results The NG showed 16.66% of cases suggestive of bilateral noise-induced hearing loss and NSG showed 5.26%. The NG and NSG had worse thresholds than their respective control groups. Females were less susceptible to noise than males; however, when simultaneously exposed to solvents, hearing was affected in a similar way, resulting in significant differences (p < 0.05. The 40- to 49-year-old age group was significantly worse (p < 0.05 in the auditory thresholds in the NSG compared with the CNS. Conclusion The results observed in this study indicate that simultaneous exposure to noise and solvents can damage the peripheral auditory system.

  18. Comparative responses of river biofilms at the community level to common organic solvent and herbicide exposure.

    Science.gov (United States)

    Paule, A; Roubeix, V; Swerhone, G D W; Roy, J; Lauga, B; Duran, R; Delmas, F; Paul, E; Rols, J L; Lawrence, J R

    2016-03-01

    that the concentration-dependent effect of alachlor mainly remains limited to biomass and growth inhibition without apparent changes of structural and functional characteristics measured. Our work also establishes the potential toxic effects of organic solvents on river biofilm in ecotoxicological experiments. For the ecotoxicological experiments, the alternative of dissolution in organic solvent followed by its evaporation, depositing the chemical on a glass surface prior to dissolution in river water used here, appears to allow exposure while minimizing the effect of organic solvent.

  19. Parental Occupational Exposure to Organic Solvents and Testicular Germ Cell Tumors in their Offspring

    DEFF Research Database (Denmark)

    Le Cornet, Charlotte; Fervers, Béatrice; Pukkala, Eero

    2017-01-01

    BACKGROUND: Testicular germ cell tumors (TGCT) were suggested to have a prenatal environmentally related origin. The potential endocrine disrupting properties of certain solvents may interfere with the male genital development in utero. OBJECTIVES: We aimed to assess the association between......-Nordic Occupational Cancer Study Job-Exposure Matrix. Conditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Overall, no association was found between prenatal maternal exposure to solvents and TGCT risk. In subset analyses using only mothers for whom...

  20. Measurement and prediction of dabigatran etexilate mesylate Form II solubility in mono-solvents and mixed solvents

    International Nuclear Information System (INIS)

    Xiao, Yan; Wang, Jingkang; Wang, Ting; Ouyang, Jinbo; Huang, Xin; Hao, Hongxun; Bao, Ying; Fang, Wen; Yin, Qiuxiang

    2016-01-01

    Highlights: • Solubility of DEM Form II in mono-solvents and binary solvent mixtures was measured. • Regressed UNIFAC model was used to predict the solubility in solvent mixtures. • The experimental solubility data were correlated by different models. - Abstract: UV spectrometer method was used to measure the solubility data of dabigatran etexilate mesylate (DEM) Form II in five mono-solvents (methanol, ethanol, ethane-1,2-diol, DMF, DMAC) and binary solvent mixtures of methanol and ethanol in the temperature range from 287.37 K to 323.39 K. The experimental solubility data in mono-solvents were correlated with modified Apelblat equation, van’t Hoff equation and λh equation. GSM model and Modified Jouyban-Acree model were employed to correlate the solubility data in mixed solvent systems. And Regressed UNIFAC model was used to predict the solubility of DEM Form II in the binary solvent mixtures. Results showed that the predicted data were consistent with the experimental data.

  1. Solvent exposure and related work practices amongst apprentice spray painters in automotive body repair workshops.

    Science.gov (United States)

    Winder, C; Turner, P J

    1992-08-01

    As part of a multidisciplinary study into the health effects of solvents, workplace assessments and airborne solvent vapour monitoring was conducted in 46 spray painting workshops in the Sydney metropolitan area. Breathing-zone samples were taken from 50 apprentices and 14 experienced spray painters. An interview schedule was developed to obtain information about the use of acrylic or two-pack paint systems, the use of engineering controls, the use of personal protective equipment and the availability of material safety data sheets. Contaminants typical of the chemical products used in this industry were encountered (aromatic hydrocarbons, C5-C7 aliphatic hydrocarbons, ketones, esters). The results of airborne solvent monitoring indicate a total solvent exposure in the range 1-99% of a combined Worksafe Australia exposure standard, with a mean of 19%. Solvent exposure was highest when spraying acrylic paint in the open workshop and lowest when spraying two pack paint in a spray booth. Much the same personal protective equipment was available in all workshops, but wide variation in its use was observed. Material safety data sheets were not observed in any of the workshops.

  2. Effect of Contemporary Exposure to Mixed Organic Solvents and Occupational Noise on Hearing Thresholds of Workers

    Directory of Open Access Journals (Sweden)

    Attarchi Mir Saeid

    2010-03-01

    Full Text Available Background: Mixed organic solvent exposure, as well as noise, has a wide spread in different industries. In recent years it has been propounded that simultaneous exposure to mixed organic solvents and occupational noise can establish a hearing loss that is more severe than hearing loss due to exposure to each of them separately.Materials & Methods: A descriptive- analytic study was conducted during 2008 in an automobile industry on 441 employees in three different groups. First group were assembly workers that only exposed to noise. The second group included employees in new painting saloon that exposed not only to noise but also to permissible levels of mixed organic solvents and the third group were employees in old painting saloon that exposed to noise and mixed organic solvents in more than threshold limit value (TLV level. The prevalence of hearing loss was compared between three groups on the basis of model 1 (mean hearing threshold in frequencies 0.5, 1 and 2 KHz more than 25dB and model 2 (mean hearing threshold in frequencies 3, 4, 6 and 8 KHz more than 25dB. Results: According to model 2, in workers exposed to noise in addition to mixed organic solvents, the rate of hearing loss, was significantly higher than workers exposed to noise alone (P<0.05, even after adjusting for confounding variables using logistic regression analysis (OR= 4.12 , P<0.001.Conclusion: In workers with simultaneous exposure to mixed organic solvents and noise, special attention must be paid to accurate accomplishment of hearing conservation programs including doing audiometric exams in shorter periods and take advantage of hearing protection devices with higher noise reduction rate (NRR.

  3. Occupational exposures to solvents and metals are associated with fixed airflow obstruction

    NARCIS (Netherlands)

    Alif, Sheikh M; Dharmage, Shyamali C; Benke, Geza; Dennekamp, Martine; Burgess, John A; Perret, Jennifer L; Lodge, Caroline J; Morrison, Stephen; Johns, David P; Giles, Graham G.; Gurrin, Lyle C; Thomas, Paul S; Hopper, John L; Wood-Baker, Richard; Thompson, Bruce R; Feather, Iain H; Vermeulen, Roel; Kromhout, Hans; Walters, E Haydn; Abramson, Michael J; Matheson, Melanie C

    2017-01-01

    Objectives This study investigated the associations between occupational exposures to solvents and metals and fixed airflow obstruction (AO) using post-bronchodilator spirometry. Methods We included 1335 participants from the 2002-2008 follow-up of the Tasmanian Longitudinal Health Study.

  4. Occupational exposure to solvents, metals and welding fumes and risk of Parkinson's disease

    NARCIS (Netherlands)

    van der Mark, Marianne; Vermeulen, Roel; Nijssen, Peter C G; Mulleners, Wim M; Sas, Antonetta M G; van Laar, Teus; Huss, Anke; Kromhout, Hans

    OBJECTIVES: The aim of this study was to investigate the potential association between occupational exposure to solvents, metals and/or welding fumes and risk of developing Parkinson's disease (PD). METHODS: Data of a hospital based case-control study including 444 PD patients and 876 age and sex

  5. Measuring exposure to organochlorinated pesticides

    Directory of Open Access Journals (Sweden)

    Gulnar Azevedo e Silva Mendonça

    1998-01-01

    Full Text Available Environmental epidemiological investigations in cancer remain, with rare exceptions, inconclusive. The difficulties of establishing patterns of measurements of exposure in the human body is one of the limitations of these studies. The findings of six recent epidemiological studies that analyzed the association between organochlorinated compounds and breast cancer are reviewed in considering the problems of measuring environmental exposure through biological markers. The epidemiological evidence based on these studies do not indicate a risk of breast cancer related to organochlorines. Some aspects that may partially explain this absence of risk are discussed regarding the investigation of environmental carcinogenic agents in populations with low but homogeneously sprayed levels of exposure.

  6. Response Mechanisms in Serratia marcescens IBBPo15 During Organic Solvents Exposure.

    Science.gov (United States)

    Stancu, Mihaela Marilena

    2016-12-01

    Serratia marcescens strain IBB Po15 (KT315653) which possesses serratiopeptidase (ser) gene (KT894207) exhibited good solvent tolerance. During the exposure of S. marcescens IBB Po15 cells to 5 % organic solvents, n-decane was less toxic for this bacterium, compared with n-hexane, cyclohexane, ethylbenzene, toluene, and styrene. The exposure of the S. marcescens IBB Po15 cells to n-hexane, cyclohexane, ethylbenzene, toluene, and styrene induced the formation of large clusters, while in control and n-decane-exposed cells, only organization into small clusters was observed. The data obtained suggested that S. marcescens IBB Po15 cells produced some secondary metabolites (i.e., surfactant serrawettin, red pigment prodigiosin) which are well known as valuable molecules due to their large applications. The exposure of the bacterial cells to organic solvents induced secondary metabolites profile modifications. However, S. marcescens IBB Po15 possesses only alkB1, todM, rhlAB, pswP, mpr, and ser genes, the unspecific amplification of other fragments being acquired also when the primers for alkM1, xylM, ndoM, and C23DO genes were used. Modifications of DNA patterns were not depicted in S. marcescens IBB Po15 cells exposed to organic solvents.

  7. Long-term occupational exposure to organic solvents affects color vision, contrast sensitivity and visual fields.

    Directory of Open Access Journals (Sweden)

    Thiago Leiros Costa

    Full Text Available The purpose of this study was to evaluate the visual outcome of chronic occupational exposure to a mixture of organic solvents by measuring color discrimination, achromatic contrast sensitivity and visual fields in a group of gas station workers. We tested 25 workers (20 males and 25 controls with no history of chronic exposure to solvents (10 males. All participants had normal ophthalmologic exams. Subjects had worked in gas stations on an average of 9.6 ± 6.2 years. Color vision was evaluated with the Lanthony D15d and Cambridge Colour Test (CCT. Visual field assessment consisted of white-on-white 24-2 automatic perimetry (Humphrey II-750i. Contrast sensitivity was measured for sinusoidal gratings of 0.2, 0.5, 1.0, 2.0, 5.0, 10.0 and 20.0 cycles per degree (cpd. Results from both groups were compared using the Mann-Whitney U test. The number of errors in the D15d was higher for workers relative to controls (p<0.01. Their CCT color discrimination thresholds were elevated compared to the control group along the protan, deutan and tritan confusion axes (p<0.01, and their ellipse area and ellipticity were higher (p<0.01. Genetic analysis of subjects with very elevated color discrimination thresholds excluded congenital causes for the visual losses. Automated perimetry thresholds showed elevation in the 9°, 15° and 21° of eccentricity (p<0.01 and in MD and PSD indexes (p<0.01. Contrast sensitivity losses were found for all spatial frequencies measured (p<0.01 except for 0.5 cpd. Significant correlation was found between previous working years and deutan axis thresholds (rho = 0.59; p<0.05, indexes of the Lanthony D15d (rho=0.52; p<0.05, perimetry results in the fovea (rho= -0.51; p<0.05 and at 3, 9 and 15 degrees of eccentricity (rho= -0.46; p<0.05. Extensive and diffuse visual changes were found, suggesting that specific occupational limits should be created.

  8. Clustering of Sun Exposure Measurements

    OpenAIRE

    Have, Anna Szynkowiak; Larsen, Jan; Hansen, Lars Kai; Philipsen, Peter Alshede; Thieden, Elisabeth; Wulf, Hans Christian

    2002-01-01

    In a medically motivated Sun-exposure study, questionnaires concerning Sun-habits were collected from a number of subjects together with UV radiation measurements. This paper focuses on identifying clusters in the heterogeneous set of data for the purpose of understanding possible relations between Sun-habits exposure and eventually assessing the risk of skin cancer. A general probabilistic framework originally developed for text and Web mining is demonstrated to be useful for clustering of b...

  9. Hobbies with solvent exposure and risk of non-Hodgkin lymphoma.

    Science.gov (United States)

    Colt, Joanne S; Hartge, Patricia; Davis, Scott; Cerhan, James R; Cozen, Wendy; Severson, Richard K

    2007-05-01

    Occupational exposure to solvents has been reported to increase non-Hodgkin lymphoma (NHL) risk in some, but not all, studies. In a population-based case-control study, we examined whether participation in selected hobbies involving solvent exposure increases NHL risk. We identified NHL cases diagnosed at ages 20-74 years between 1998 and 2000 in Iowa or metropolitan Los Angeles, Detroit, and Seattle. Controls were selected using random digit dialing or Medicare files. Computer-assisted personal interviews (551 cases, 462 controls) elicited data on model building, painting/silkscreening/artwork, furniture refinishing, and woodworking/home carpentry. Hobby participation (68% of cases, 69% of controls) was not associated with NHL risk (OR = 0.9, 95% CI = 0.7-1.2). Compared to people with none of the hobbies evaluated, those who built models had significantly lower risk (OR = 0.7, CI = 0.5-1.0), but risk did not vary with the number of years or lifetime hours. Risk estimates for the other hobbies were generally less than one, but the associations were not significant and there were no notable patterns with duration of exposure. Use of oil-based, acrylic, or water-based paints; paint strippers; polyurethane; or varnishes was not associated with NHL risk. We conclude that participation in hobbies involving exposure to organic solvents is unlikely to increase NHL risk.

  10. Is occupational exposure to solvents associated with an increased risk for developing systemic scleroderma?

    Directory of Open Access Journals (Sweden)

    Drexler Hans

    2006-07-01

    Full Text Available Abstract Background Our study was aimed to investigate in a German collective if there are any hints for an increased occupational or environmental risk to develop systemic sclerosis, especially, focussing on work-related exposure to solvents. Moreover, we tried to evaluate the feasibility of a sampling method addressing support groups. Methods A standardised questionnaire was published in two journals subscribed by members of two different support groups and all members were asked to complete the questionnaire and to return it anonymously. The subjects were not informed on the scientific hypotheses, nor did they know who of them belonged to the case group (scleroderma or to the control group (multiple sclerosis. Results 175 questionnaires could be included in the statistical analysis. As expected, a female predominance was in our collective. In the male subpopulation, the occupational exposure to solvents was higher in the case group than in the control-group (70% versus 45.8%. Based only on the male subgroup, a tendency for an association between occupational exposure to solvents and the risk to develop systemic sclerosis was found. Conclusion According to our experience in this case-control-study exposure misclassification, qualitative or quantitative, was an eminent problem. Within such a setting, it is generally very difficult to establish an exact dose-response relationship due to incomplete, imprecise or missing data concerning duration of exposure, frequency of use and kind of solvent. Additionally, a well-known problem in studies based on self-reported questionnaires is the so-called volunteer bias. Unfortunately, but similar to other studies assessing epidemiologic factors in such a rare disease, our study was of limited power, especially in the subgroups defined by gender.

  11. Part I: the effect of long-term exposure to organic solvents on memory: a cross sectional study.

    Science.gov (United States)

    Ratzon, N Z; Vakil, E; Derazne, E; Sculsky, M

    1998-01-01

    This study focuses on a wide range of different aspects of memory functions trying to ascertain a possible profile of memory changes, which take place following long-term exposure to organic solvents. The research design was cross-sectional. Study population included 31 industrial painters who were exposed at work to organic solvents and 31 unexposed workers. Workers after long-term exposure to organic solvents showed significant decline in memory as indicated in all three standard memory tests (i.e. Wechsler Memory Scale - Revised, Benton Revised Visual Retention Test, and Rey Auditory Verbal Learning Test). The results of Rey Auditory Verbal Learning Test showed a negative correlation with exposure index indicating that the more intensive and longer the time of exposure was, the more impaired is the verbal memory. It was also found that the affect of age on memory was stronger among workers after long-term exposure to organic solvents compared to the unexposed workers.

  12. P1-11: Visual Function and Neurotoxic Symptoms Related to Exposure to Organic Solvents

    Directory of Open Access Journals (Sweden)

    Ingrid Jimenez Barbosa

    2012-10-01

    Full Text Available Aim: Exposure to Perchloroethylene (PERC, a solvent used in dry-cleaning, is associated with neurotoxicity and changes in colour vision (CV and contrast sensitivity (CS. However, PERCs' impact on other aspects of visual function (VF such as chromatic contrast sensitivity (CCS, glass pattern detection (GPP, visual search (VS, and global motion sensitivity (GMS remains unclear. This study compared VF and neurotoxicity in two populations at risk, dry-cleaners (cases from Colombia and Australia. Control groups of people with community levels of exposure to PERC were also assessed. Methods: A case-control study of VF in people who are working in the dry-cleaning industry for at least 1 year (n = 40 Colombia; n= 34 Australia with controls (n = 35 each site. VF measures assessed were CSF, CCS, the FM Hue 100 test, VS, GPP, and GMS. Neurotoxic symptoms were assessed using the Q16 modified version questionnaire. Results: Cases had poorer CCS, hue discrimination, GPP, GMS, and higher Q16 scores than controls (p < .05. There was no effect of country. CS function was poorer than controls (p < .05 for spatial frequencies≥0.50 cpd for Australian cases but for ≥1.0 cpd for Colombian cases. There were no significant differences between cases and controls for serial and parallel VS. Conclusion: Our CSF and CV findings indicate that the CS deficit extends to lower spatial frequencies. Furthermore we report a reduction in the detection of form, motion, and CCS. These deficits were associated with neurotoxic symptoms. Because VS was unaffected, it suggests that PERC affects lower order visual functions more severely than higher level cognition.

  13. Clustering of Sun Exposure Measurements

    DEFF Research Database (Denmark)

    Have, Anna Szynkowiak; Larsen, Jan; Hansen, Lars Kai

    2002-01-01

    In a medically motivated Sun-exposure study, questionnaires concerning Sun-habits were collected from a number of subjects together with UV radiation measurements. This paper focuses on identifying clusters in the heterogeneous set of data for the purpose of understanding possible relations between...... Sun-habits exposure and eventually assessing the risk of skin cancer. A general probabilistic framework originally developed for text and Web mining is demonstrated to be useful for clustering of behavioral data. The framework combines principal component subspace projection with probabilistic...

  14. Occupational exposure to organic solvents: a risk factor for pulmonary veno-occlusive disease.

    Science.gov (United States)

    Montani, David; Lau, Edmund M; Descatha, Alexis; Jaïs, Xavier; Savale, Laurent; Andujar, Pascal; Bensefa-Colas, Lynda; Girerd, Barbara; Zendah, Inès; Le Pavec, Jerome; Seferian, Andrei; Perros, Frédéric; Dorfmüller, Peter; Fadel, Elie; Soubrier, Florent; Sitbon, Oliver; Simonneau, Gérald; Humbert, Marc

    2015-12-01

    Pulmonary veno-occlusive disease (PVOD) is a rare form of pulmonary hypertension characterised by predominant remodelling of pulmonary venules. Bi-allelic mutations in the eukaryotic translation initiation factor 2α kinase 4 (EIF2AK4) gene were recently described as the major cause of heritable PVOD, but risk factors associated with PVOD remain poorly understood. Occupational exposures have been proposed as a potential risk factor for PVOD, but epidemiological studies are lacking.A case-control study was conducted in consecutive PVOD (cases, n=33) and pulmonary arterial hypertension patients (controls, n=65). Occupational exposure was evaluated via questionnaire interview with blinded assessments using an expert consensus approach and a job exposure matrix (JEM).Using the expert consensus approach, PVOD was significantly associated with occupational exposure to organic solvents (adjusted OR 12.8, 95% CI 2.7-60.8), with trichloroethylene being the main agent implicated (adjusted OR 8.2, 95% CI 1.4-49.4). JEM analysis independently confirmed the association between PVOD and trichloroethylene exposure. Absence of significant trichloroethylene exposure was associated with a younger age of disease (54.8±21.4 years, p=0.037) and a high prevalence of harbouring bi-allelic EIF2AK4 mutations (41.7% versus 0%, p=0.015).Occupational exposure to organic solvents may represent a novel risk factor for PVOD. Genetic background and environmental exposure appear to influence the phenotypic expression of the disease. Copyright ©ERS 2015.

  15. Haematological and biochemical pattern in occupational organic solvent poisoning and exposure

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, L M; Rasmussen, J M

    1982-12-01

    A haematological and biochemical investigation was undertaken in 122 consecutive male patients with suspected organic solvent poisoning due to exposure to a mixture of organic solvents such as turpentine, toluene and xylene. Sixty-four healthy solvent exposed and 91 healthy non-exposed male volunteers were used as controls. The only statistically significant differences were that in the patients (B)-leucocytes and S-creatinine were lower than in the controls. (B)-monocytes were higher in all exposed groups than in the controls. S-creatine kinase was higher in patients actually exposed at the examination time, than in all other groups. It is concluded that there was no characteristic haematological and biochemical pattern that could be of value in the individual diagnosis of organic solvent poisoning. The patients and the controls were seen as out-patients. In all groups studied, more than 10% of the results of reticulocytes, leucocytes, sedimentaition rate, orosomucoid and creatine kinase exceeded the upper level of the reference interval, which is based on in-patients. New reference intervals for these 5 analyses, valid for ambulantly examined subjects, should be worked out.

  16. Parental Occupational Exposure to Organic Solvents and Testicular Germ Cell Tumors in their Offspring: NORD-TEST Study.

    Science.gov (United States)

    Le Cornet, Charlotte; Fervers, Béatrice; Pukkala, Eero; Tynes, Tore; Feychting, Maria; Hansen, Johnni; Togawa, Kayo; Nordby, Karl-Christian; Oksbjerg Dalton, Susanne; Uuksulainen, Sanni; Wiebert, Pernilla; Woldbæk, Torill; Skakkebæk, Niels E; Olsson, Ann; Schüz, Joachim

    2017-06-30

    Testicular germ cell tumors (TGCT) were suggested to have a prenatal environmentally related origin. The potential endocrine disrupting properties of certain solvents may interfere with the male genital development in utero . We aimed to assess the association between maternal and paternal occupational exposures to organic solvents during the prenatal period and TGCT risk in their offspring. This registry-based case control study included TGCT cases aged 14–49 y ( n =8,112) diagnosed from 1978 to 2012 in Finland, Norway, and Sweden. Controls ( n =26,264) were randomly selected from the central population registries and were individually matched to cases on year and country of birth. Occupational histories of parents prior to the child’s birth were extracted from the national censuses. Job codes were converted into solvent exposure using the Nordic job-Nordic Occupational Cancer Study Job-Exposure Matrix. Conditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). Overall, no association was found between prenatal maternal exposure to solvents and TGCT risk. In subset analyses using only mothers for whom occupational information was available in the year of or in the year prior to the child’s birth, there was an association with maternal exposure to aromatic hydrocarbon solvents (ARHC) (OR=1.53; CI: 1.08, 2.17), driven by exposure to toluene (OR=1.67; CI: 1.02, 2.73). No association was seen for any paternal occupational exposure to solvents with the exception of exposure to perchloroethylene in Finland (OR=2.42; CI: 1.32, 4.41). This study suggests a modest increase in TGCT risk associated with maternal prenatal exposure to ARHC. https://doi.org/10.1289/EHP864.

  17. Pregnancy outcome after risk assessment of occupational exposure to organic solvents: a prospective cohort study.

    Science.gov (United States)

    Testud, François; D'Amico, Andrea; Lambert-Chhum, Rachel; Garayt, Christelle; Descotes, Jacques

    2010-11-01

    A rational medical, occupational and toxicological approach is instrumental to select objectively among pregnant women exposed to chemicals at the workplace those who should be withdrawn or benefit from improvements of working conditions. Risk assessment is based on a comprehensive review of compounds' hazards and a thorough evaluation of the actual exposure including biomonitoring whenever as possible. Since 1996, the Lyon Poison Center has been conducting a prospective follow-up of pregnant women exposed to chemicals at the workplace. Of these, 206 exposed to organic solvents since conception were selected and matched with 206 exposed to a non-embryotoxic agent. Total withdrawal from the workplace was recommended in 22% of cases, but exposure was not considered to be hazardous to pregnancy in 51%. Overall, no increase in adverse outcomes was found. Maintaining pregnant women at their workplace, particularly most of the laboratory technicians, is reasonably possible after careful toxicological risk assessment. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. Measurement and prediction of aromatic solute distribution coefficients for aqueous-organic solvent systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, J.R.; Luthy, R.G.

    1984-06-01

    Experimental and modeling activities were performed to assess techniques for measurement and prediction of distribution coefficients for aromatic solutes between water and immiscible organic solvents. Experiments were performed to measure distribution coefficients in both clean water and wastewater systems, and to assess treatment of a wastewater by solvent extraction. The theoretical portions of this investigation were directed towards development of techniques for prediction of solute-solvent/water distribution coefficients. Experiments were performed to assess treatment of a phenolic-laden coal conversion wastewater by solvent extraction. The results showed that solvent extraction for recovery of phenolic material offered several wastewater processing advantages. Distribution coefficients were measured in clean water and wastewater systems for aromatic solutes of varying functionality with different solvent types. It was found that distribution coefficients for these compounds in clean water systems were not statistically different from distribution coefficients determined in a complex coal conversion process wastewater. These and other aromatic solute distribution coefficient data were employed for evaluation of modeling techniques for prediction of solute-solvent/water distribution coefficients. Eight solvents were selected in order to represent various chemical classes: toluene and benzene (aromatics), hexane and heptane (alkanes), n-octanol (alcohols), n-butyl acetate (esters), diisopropyl ether (ethers), and methylisobutyl ketone (ketones). The aromatic solutes included: nonpolar compounds such as benzene, toluene and naphthalene, phenolic compounds such as phenol, cresol and catechol, nitrogenous aromatics such as aniline, pyridine and aminonaphthalene, and other aromatic solutes such as naphthol, quinolinol and halogenated compounds. 100 references, 20 figures, 34 tables.

  19. Occupational exposures to solvents and lead as risk factors for Alzheimer's disease: A collaborative re-analysis of case-control studies

    NARCIS (Netherlands)

    A.B. Graves; C.M. van Duijn (Cornelia); V. Chandra; L. Fratiglioni (Laura); A. Heyman; A.F. Jorm; E. Kokmen (Emre); K. Kondo; J.A. Mortimer; W.A. Rocca; S.L. Shalat; H. Soininen; A. Hofman (Albert)

    1991-01-01

    textabstractA meta-analysis, involving the secondary analysis of original data from 11 case-control studies of Alzheimer's disease, is presented for occupational exposures to solvents and lead. Three studies had data on occupational exposure to solvents. Among cases, 21.3% were reported to have been

  20. Safety measures in exposure room

    International Nuclear Information System (INIS)

    Muhammad Jamal Md Isa

    2004-01-01

    The contents of this chapter are follows - The exposure room: location and dimension, material and thickness, windows, doors and other openings; Position of the Irradiating Apparatus, Use of Space Adjoining the Room, Warning Signs/Light, Dark Room. Materials and Apparatus: Classification of Areas, Local Rules, Other General Safety Requirements

  1. The risk of hearing loss associated with occupational exposure to organic solvents mixture with and without concurrent noise exposure: A systematic review and meta-analysis.

    Science.gov (United States)

    Hormozi, Maryam; Ansari-Moghaddam, Alireza; Mirzaei, Ramazan; Dehghan Haghighi, Javid; Eftekharian, Fatemeh

    2017-06-19

    This study is a meta-analysis of the previous epidemiological studies which investigated the quantitative estimates of the association between independent or combined exposure to noise and mixed organic solvents and hearing loss until October 2014. Overall, 15 studies with information on 7530 individuals (6% female) were included. Having assessed - by puretone audiometry - the adjusted odds ratio estimates for the association between solvents mixture exposure and the risk of developing hearing loss stood at 2.05 (95% confidence interval (CI): 1.44-2.9). Similarly, for subjects who were concurrently exposed to noise and solvents mixture, an OR of 2.95 (95% CI: 2.1-4.17) was obtained. There was some evidence of heterogeneity within each of the 2 exposure groups (p heterogeneity hearing loss for workers exposed to organic solvents even at quite low concentration. Moreover, if such exposure is accompanied by noise, it will exacerbate the extent of hearing loss. Int J Occup Med Environ Health 2017;30(4):521-535. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  2. Comprehensive Biological Monitoring to Assess Isocyanates and Solvents Exposure in the NSW Australia Motor Vehicle Repair Industry.

    Science.gov (United States)

    Hu, Jimmy; Cantrell, Phillip; Nand, Aklesh

    2017-10-01

    Urethane products that contain isocyanates are extensively used in the motor vehicle repair (MVR) industry and other industries such as furniture and cabinet-making as two-pack spray paints, clears, and adhesives. Attention has recently been refocussed on isocyanate-containing chemicals, particularly in paints. The spray painters in the MVR industry had a propensity to develop industrial asthma at a rate 80 times higher than the general public, which was previously reported in the UK. To track workers exposure to isocyanates, urine samples were collected from 196 spray painters who worked mainly in 78 MVR shops across 54 New South Wales (NSW) towns and suburbs. The biological monitoring also covered exposure testing to a wide variety of solvents including aromatic hydrocarbons, ketones, and alcohols. The main finding of the study was that 2.6% of the spray painters surveyed in the MVR industry in NSW that handled isocyanate-containing paints showed exposure to isocyanates; with 1.0% being moderately exposed, which is more than twice the current UK's Health and Safety Executive (HSE) Biological Monitoring Guidance Value (BMGV) of 1 µmol mol-1 creatinine. Potential exposures to toluene (a solvent often found in paint thinners) was monitored via hippuric acid (HA) urine levels and showed 2.6% of the spray painters surveyed to be over the US' American Conference of Government Industrial Hygienists (ACGIH) Biological Exposure Index (BEI) of 1010 mmol/mole creatinine for HA. The other solvents or their metabolites were all below their respective BEI; these comprised benzene, xylene, ethyl benzene, methyl ethyl ketone, acetone, methanol, and ethanol. These findings indicate that isocyanates and certain solvents exposure were occurring in the NSW Australia vehicle repair industry, albeit at lower levels than previous occupational biological monitoring studies that showed higher exposure levels, particularly for isocyanates. One reason for this could be the increasing use

  3. Aircrew radiation exposure: sources-risks-measurement

    International Nuclear Information System (INIS)

    Duftschmid, K.E.

    1994-05-01

    A short review is given on the actual aircrew exposure and its sources. The resulting risks for harmful effects to the health and discuss methods for in-flight measurements of exposure is evaluated. An idea for a fairly simple and economic approach to a practical, airborne active dosimeter for the assessment of individual crew exposure is presented. The exposure of civil aircrew to cosmic radiation, should not be considered a tremendous risk to the health, there is no reason for panic. However, being significantly higher than the average exposure to radiation workers, it can certainly not be neglected. As recommended by ICRP, aircrew exposure has to be considered occupational radiation exposure and aircrews are certainly entitled to the same degree of protection, as other ground-based radiation workers have obtained by law, since long time. (author)

  4. Solvent exposure and malignant lymphoma: a population-based case-control study in Germany

    Directory of Open Access Journals (Sweden)

    Deeg Evelin

    2007-04-01

    Full Text Available Abstract Aims To analyze the relationship between exposure to chlorinated and aromatic organic solvents and malignant lymphoma in a multi-centre, population-based case-control study. Methods Male and female patients with malignant lymphoma (n = 710 between 18 and 80 years of age were prospectively recruited in six study regions in Germany (Ludwigshafen/Upper Palatinate, Heidelberg/Rhine-Neckar-County, Würzburg/Lower Frankonia, Hamburg, Bielefeld/Gütersloh, and Munich. For each newly recruited lymphoma case, a gender, region and age-matched (± 1 year of birth population control was drawn from the population registers. In a structured personal interview, we elicited a complete occupational history, including every occupational period that lasted at least one year. On the basis of job task-specific supplementary questionnaires, a trained occupational physician assessed the exposure to chlorinated hydrocarbons (trichloroethylene, tetrachloroethylene, dichloromethane, carbon tetrachloride and aromatic hydrocarbons (benzene, toluene, xylene, styrene. Odds ratios (OR and 95% confidence intervals (CI were calculated using conditional logistic regression analysis, adjusted for smoking (in pack years and alcohol consumption. To increase the statistical power, patients with specific lymphoma subentities were additionally compared with the entire control group using unconditional logistic regression analysis. Results We observed a statistically significant association between high exposure to chlorinated hydrocarbons and malignant lymphoma (Odds ratio = 2.1; 95% confidence interval 1.1–4.3. In the analysis of lymphoma subentities, a pronounced risk elevation was found for follicular lymphoma and marginal zone lymphoma. When specific substances were considered, the association between trichloroethylene and malignant lymphoma was of borderline statistical significance. Aromatic hydrocarbons were not significantly associated with the lymphoma diagnosis

  5. Measurement and correlation of solubility of ciclesonide in seven pure organic solvents

    International Nuclear Information System (INIS)

    Zhou, Lina; Yin, Qiuxiang; Guo, Zhiqiang; Lu, Haijiao; Liu, Mingyan; Chen, Wei; Hou, Baohong

    2017-01-01

    Highlights: • The solubility of ciclesonide in seven pure organic solvents was determined by gravimetric method. • The solubility order was interpreted by virtue of density function theory (DFT). • The experimental solubility of ciclesonide was correlated by four thermodynamic models. • Mixing thermodynamic properties of ciclesonide were calculated and discussed. - Abstract: The solubility of ciclesonide in seven organic solvents (ethanol, 2-propanol, 1-propanol, 1-butanol, acetonitrile, toluene and ethyl acetate) in the temperature range from 278.15 K to 313.15 K was measured by gravimetrical method under atmospheric pressure. The results indicate that the solubility of ciclesonide increases with elevating temperature in all investigated solvents. The solubility order in different solvents was interpreted through comparing interaction force between solute and solvent molecules by virtue of density function theory (DFT). Thermodynamic equations including the modified Apelblat equation, λh equation, Wilson equation and NRTL equation are all suitable to correlate the solubility results. Based on the Wilson equation, the thermodynamic parameters from the mixing process are calculated, and the results indicate the mixing process of ciclesonide in the selected pure solvents is spontaneous and entropy-driven.

  6. Effect of Different Solvents on the Measurement of Phenolics and the Antioxidant Activity of Mulberry (Morus atropurpurea Roxb.) with Accelerated Solvent Extraction.

    Science.gov (United States)

    Yang, Jiufang; Ou, XiaoQun; Zhang, Xiaoxu; Zhou, ZiYing; Ma, LiYan

    2017-03-01

    The effects of 9 different solvents on the measurement of the total phenolics and antioxidant activities of mulberry fruits were studied using accelerated solvent extraction (ASE). Sixteen to 22 types of phenolics (flavonols, flavan-3-ols, flavanol, hydroxycinnamic acids, hydroxybenzoic acids, and stilbenes) from different mulberry extracts were characterized and quantified using HPLC-MS/MS. The principal component analysis (PCA) was used to determine the suitable solvents to distinguish between different classes of phenolics. Additionally, the phenolic extraction abilities of ASE and ultrasound-assisted extraction (UAE) were compared. The highest extraction efficiency could be achieved by using 50% acidified methanol (50MA) as ASE solvents with 15.14 mg/gallic acid equivalents g dry weight of mulberry fruit. The PCA results revealed that the 50MA followed by 50% acidified acetone (50AA) was the most efficient solvent for the extraction of phenolics, particularly flavonols (627.12 and 510.31 μg/g dry weight, respectively), while water (W) was not beneficial to the extraction of all categories of phenolics. Besides, the results of 3 antioxidant capability assays (DPPH, ABTS free radical-scavenging assay, and ferric-reducing antioxidant power assay) showed that water-based organic solvents increased the antioxidant capabilities of the extracts compared with water or pure organic solvents. ASE was more suitable for the extraction of phenolics than UAE. © 2017 Institute of Food Technologists®.

  7. Measuring and exposures from National Media Surveys

    DEFF Research Database (Denmark)

    Mortensen, Peter Stendahl

    2000-01-01

    Natinal media surveys inform about the number and kind of people being exposed to the media in question. This paper discusses to what extent these numbers may be used as measures for the exposure to ads in the media in question. In this context attention is also focussed on elements in the media ...... surveys themselves that might invalidate or give unreliable measures, both when measuring a single exposure and accumulated exposures. Four media types will be discussed: TV, radio, print and the internet.......Natinal media surveys inform about the number and kind of people being exposed to the media in question. This paper discusses to what extent these numbers may be used as measures for the exposure to ads in the media in question. In this context attention is also focussed on elements in the media...

  8. Selective solvent extraction of actinides associated to liquid scintillation measurements

    International Nuclear Information System (INIS)

    Ardois, C.; Musikas, C.

    1997-01-01

    The problems associated to radioactive waste disposal have acquired a special attention due, particularly, to the element instability and, consequently, to their lixiviation and to their peculiarities which are essential in the radioactivity penetration in the food chains; the other important parameters are the produced amounts and the noxiousnesses. New commercial liquid scintillation counters allow rapid α/β measurements. Associated with liquid-liquid extraction techniques, rapid and selective actinide analyses are possible. Among various actinide extractants, such as amines or organophosphorus compounds, we were particularly interested in tri-n-octyl-phosphine oxide (TOPO). Uranium, thorium and americium extractions with (TOPO) in toluene have been investigated. A systematic study of the counting parameters of a PACKARD 2550 TR/AB TM liquid scintillation analyzer is under completion

  9. The estimation of heavy metal concentration in FBR reprocessing solvent streams by density measurement

    International Nuclear Information System (INIS)

    Brown, M.L.; Savage, D.J.

    1986-04-01

    The application of density measurement to heavy metal monitoring in the solvent phase is described, including practical experience gained during three fast reactor fuel reprocessing campaigns. An experimental algorithm relating heavy metal concentration and sample density was generated from laboratory-measured density data, for uranyl nitrate dissolved in nitric acid loaded tri-butyl phosphate in odourless kerosene. Differences in odourless kerosene batch densities are mathematically interpolated, and the algorithm can be used to estimate heavy metal concentrations from the density to within +1.5 g/l. An Anton Paar calculating digital densimeter with remote cell operation was used for all density measurements, but the algorithm will give similar accuracy with any density measuring device capable of a precision of better than 0.0005 g/cm 3 . For plant control purposes, the algorithm was simplified using a density referencing system, whereby the density of solvent not yet loaded with heavy metal is subtracted from the sample density. This simplified algorithm compares very favourably with empirical algorithms, derived from numerical analysis of density data and chemically measured uranium and plutonium data obtained during fuel reprocessing campaigns, particularly when differences in the acidity of the solvent are considered before and after loading with heavy metal. This simplified algorithm had been successfully used for plant control of heavy metal loaded solvent during four fast reactor fuel reprocessing campaigns. (author)

  10. Evaluation of the effects of exposure to organic solvents and hazardous noise among US Air Force Reserve personnel

    Directory of Open Access Journals (Sweden)

    Hayley Hughes

    2013-01-01

    Full Text Available Hearing loss affects many workers including those in the military and may be caused by noise, medications, and chemicals. Exposures to some chemicals may lead to an increase in the incidence of hearing loss when combined with hazardous noise. This retrospective study evaluated the risk for hearing loss among Air Force Reserve personnel exposed to occupational noise with and without exposures to toluene, styrene, xylene, benzene, and JP-8 (jet fuel. Risk factors associated with hearing loss were determined using logistic and linear regression. Stratified analysis was used to evaluate potential interaction between solvent and noise exposure. The majority of the subjects were male (94.6% and 35 years or older on the date of their first study audiogram (66%. Followed for an average of 3.2 years, 9.2% of the study subjects had hearing loss in at least one ear. Increasing age (odds ratio [OR] = 1.03 per year of age and each year of follow-up time (OR = 1.23 were significantly associated with hearing loss. Low and moderate solvent exposures were not associated with hearing loss. Linear regression demonstrated that hearing loss was significantly associated with age at first study audiogram, length of follow-up time, and exposure to noise. Hearing decreased by 0.04 decibels for every decibel increase in noise level or by almost half a decibel (0.4 dB for every 10 decibel increase in noise level.

  11. Measurement and correlation of the solubility of 2,3,4,5-tetrabromothiophene in different solvents

    International Nuclear Information System (INIS)

    Wang, Kai; Hu, Yonghong; Yang, Wenge; Guo, Song; Shi, Ying

    2012-01-01

    Highlights: ► The solubility of tetrabromothiophene in different solvents was investigated. ► The modified Apelblat equation was more accurate than the van’t Hoff equation and the λh equation. ► Ethyl acetate showed the potential as a better recrystallization solvent to replace trichloromethane. ► The solution process in the selected solvents was endothermic and nonspontaneous. - Abstract: The solubility of 2,3,4,5-tetrabromothiophene were measured in methanol, ethanol, propan-1-ol, butan-1-ol, toluene, ethyl formate, ethyl acetate, trichloromethane and oxolane within the temperature range between 278.05 K and 325.15 K under atmospheric pressure by gravimetric method. The solubility of 2,3,4,5-tetrabromothiophene in those selected solvents increased with increasing temperature. The solubility data were correlated with the van’t Hoff equation, the modified Apelblat equation and the λh equation. The thermodynamic properties of the solution process, including the Gibbs energy, enthalpy, and entropy were calculated by the van’t Hoff analysis and the Gibbs equation. The experimental results showed that ethyl acetate had the potential as a better solvent in the re-crystallization process of 2,3,4,5-tetrabromothiophene.

  12. Measuring water ingestion from spray exposures.

    Science.gov (United States)

    Sinclair, Martha; Roddick, Felicity; Nguyen, Thang; O'Toole, Joanne; Leder, Karin

    2016-08-01

    Characterisation of exposure levels is an essential requirement of health risk assessment; however for water exposures other than drinking, few quantitative exposure data exist. Thus, regulatory agencies must use estimates to formulate policy on treatment requirements for non-potable recycled water. We adapted the use of the swimming pool chemical cyanuric acid as a tracer of recreational water ingestion to permit detection of small water volumes inadvertently ingested from spray exposures. By using solutions of 700-1000 mg/L cyanuric acid in an experimental spray exposure scenario, we were able to quantify inadvertent water ingestion in almost 70% of participants undertaking a 10 min car wash activity using a high pressure spray device. Skin absorption was demonstrated to be negligible under the experimental conditions, and the measured ingestion volumes ranged from 0.06 to 3.79 mL. This method could be applied to a range of non-potable water use activities to generate exposure data for risk assessment processes. The availability of such empirical measurements will provide greater assurance to regulatory agencies and industry that potential health risks from exposure to non-potable water supplies are well understood and adequately managed to protect public health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Direct measurement for organic solvents diffusion using ultra-sensitive optical resonator

    Science.gov (United States)

    Ali, Amir R.; Elias, Catherine M.

    2017-06-01

    In this paper, novel techniques using ultra-sensitive chemical optical sensor based on whispering gallery modes (WGM) are proposed through two different configurations. The first one will use a composite micro-sphere, when the solvent interacts with the polymeric optical sensors through diffusion the sphere start to swallow that solvent. In turn, that leads to change the morphology and mechanical properties of the polymeric spheres. Also, these changes could be measured by tracking the WGM shifts. Several experiments were carried out to study the solvent induced WGM shift using microsphere immersed in a solvent atmosphere. It can be potentially used for sensing the trace organic solvents like ethanol and methanol. The second configuration will use a composite beam nitrocellulose composite (NC) structure that acts as a sensing element. In this configuration, a beam is anchored to a substrate in one end, and the other end is compressing the polymeric sphere causing a shift in its WGM. When a chemical molecule is attached to the beam, the resonant frequency of the cantilever will be changed for a certain amount. By sensing this certain resonant frequency change, the existence of a single chemical molecule can be detected. A preliminary experimental model is developed to describe the vibration of the beam structure. The resonant frequency change of the cantilever due to attached mass is examined imperially using acetone as an example. Breath diagnosis can use this configuration in diabetic's diagnosis. Since, solvent like acetone concentration in human breath leads to a quick, convenient, accurate and painless breath diagnosis of diabetics. These micro-optical sensors have been examined using preliminary experiments to fully investigate its response. The proposed chemical sensor can achieve extremely high sensitivity in molecular level.

  14. Quantitative self-assessment of exposure to solvents among shoe repair men

    NARCIS (Netherlands)

    Hertsenberg, S.; Brouwer, D.; Lurvink, M.; Rubingh, C.; Rijnders, E.; Tielemans, E.

    2007-01-01

    Self-assessment of exposure (SAE) refers to any exposure assessment methodology wherein the worker takes an active role in establishing his or her exposure status. The objective of this study was to investigate the reliability and feasibility of SAE approaches among shoe repair workers collecting

  15. Measuring motivations for media exposure: A thesis

    NARCIS (Netherlands)

    Hendriks Vettehen, P.G.J.; Snippenburg, L.B. van

    2002-01-01

    The present article discusses the problem of separating the motivation conceptempirically from other relevant concepts in research on mass media audiences. For about half a century, audience researchers use questionnaire items with adistinct format as measurements of motivations for media exposure.

  16. Measurement of illumination exposure in postpartum women

    Directory of Open Access Journals (Sweden)

    Stein Martin T

    2003-05-01

    Full Text Available Abstract Background Low levels of light exposure at critical times are thought to cause seasonal affective disorder. Investigators, in studies demonstrating the usefulness of bright light therapy, also have implicated light's role in non-seasonal depression. The precise cause of postpartum depression has not been delineated, but it seemed possible that new mothers would spend reduced time in daylight. The goal of this study was to examine the levels of illumination experienced by postpartum mothers and to discover any relationship between light exposure and mood levels experienced during the postpartum period. Methods Fifteen postpartum women, who did not have any baseline indication of depression, wore a wrist device (Actillume for 72 hours to measure their exposure to light. At the end of the recording period, they completed a self-reported measure of mood. The mean light exposure of these postpartum women (expressed as the 24-hour average logarithm of illumination in lux was compared with that of a representative sample of women of comparable age, residence, and seasonal months of recording. Mood levels were then rank-ordered and tested for correlation with light exposure levels. Results There was no significant difference between the amount of light [log10lux] experienced by postpartum (1.01 SD 0.236 and control women (1.06 SD 0.285. Mood was not correlated with illumination in the postpartum sample. Conclusions Postpartum women in San Diego did not receive reduced light, nor was low mood related to low illumination.

  17. Inline Monitors for Measuring Cs-137 in the SRS Caustic Side Solvent Extraction Process

    Energy Technology Data Exchange (ETDEWEB)

    Casella, V

    2006-04-24

    The Department of Energy (DOE) selected Caustic-Side Solvent Extraction (CSSX) as the preferred technology for the removal of radioactive cesium from High-Level Waste (HLW) at the Savannah River Site (SRS). Before the full-scale Salt Waste Processing Facility (SWPF) becomes operational, a portion of dissolved saltcake waste will be processed through a Modular CSSX Unit (MCU). The MCU employs the CSSX process, a continuous process that uses a novel solvent to extract cesium from waste and concentrate it in dilute nitric acid. Of primary concern is Cs-137 which makes the solution highly radioactive. Since the MCU does not have the capacity to wait for sample results while continuing to operate, the Waste Acceptance Strategy is to perform inline analyses. Gamma-ray monitors are used to: measure the Cs-137 concentration in the decontaminated salt solution (DSS) before entering the DSS Hold Tank; measure the Cs-137 concentration in the strip effluent (SE) before entering the SE Hold Tank; and verify proper operation of the solvent extraction system by verifying material balance within the process. Since this gamma ray monitoring system application is unique, specially designed shielding was developed and software was written and acceptance tested by Savannah River National Laboratory (SRNL) personnel. The software is a LabView-based application that serves as a unified interface for controlling the monitor hardware and communicating with the host Distributed Control System. This paper presents the design, fabrication and implementation of this monitoring system.

  18. Towards electron transport measurements in chemically modified graphene: effect of a solvent

    Energy Technology Data Exchange (ETDEWEB)

    Jacobsen, Arnhild; Ensslin, Klaus [Solid State Physics Laboratory, ETH Zurich (Switzerland); Koehler, Fabian M; Stark, Wendelin J, E-mail: arnhildj@phys.ethz.ch, E-mail: fabian.koehler@chem.ethz.ch [Institute for Chemical and Bioengineering, ETH Zurich (Switzerland)

    2010-12-15

    The chemical functionalization of graphene modifies the local electron density of carbon atoms and hence electron transport. Measuring these changes allows for a closer understanding of the chemical interaction and the influence of functionalization on the graphene lattice. However, not only chemistry, in this case diazonium chemistry, has an effect on electron transport. The latter is also influenced by defects and dopants resulting from different processing steps. Here, we show that the solvents used in the chemical reaction process change the transport properties. In more detail, the investigated combination of isopropanol and heating treatment reduces the doping concentration and significantly increases the mobility of graphene. Furthermore, isopropanol treatment alone increases the concentration of dopants and introduces an asymmetry between electron and hole transport, which might be difficult to distinguish from the effect of functionalization. The results shown in this work demand a closer look at the influence of solvents used for chemical modification in order to understand their influence.

  19. Towards electron transport measurements in chemically modified graphene: effect of a solvent

    International Nuclear Information System (INIS)

    Jacobsen, Arnhild; Ensslin, Klaus; Koehler, Fabian M; Stark, Wendelin J

    2010-01-01

    The chemical functionalization of graphene modifies the local electron density of carbon atoms and hence electron transport. Measuring these changes allows for a closer understanding of the chemical interaction and the influence of functionalization on the graphene lattice. However, not only chemistry, in this case diazonium chemistry, has an effect on electron transport. The latter is also influenced by defects and dopants resulting from different processing steps. Here, we show that the solvents used in the chemical reaction process change the transport properties. In more detail, the investigated combination of isopropanol and heating treatment reduces the doping concentration and significantly increases the mobility of graphene. Furthermore, isopropanol treatment alone increases the concentration of dopants and introduces an asymmetry between electron and hole transport, which might be difficult to distinguish from the effect of functionalization. The results shown in this work demand a closer look at the influence of solvents used for chemical modification in order to understand their influence.

  20. Ultrasonic measurements and other allied parameters of yttrium soaps in mixed organic solvents

    International Nuclear Information System (INIS)

    Mehrotra, K.N.; Tandon, K.

    1990-01-01

    The ultrasonic measurements of yttrium soaps were made in a mixture of 70 % benzene and 30 % dimethylsulfoxide (ν/ν) to determine the critical micelle concentration, soap-solvent interaction and various acoustic and thermodynamic parameters. The values of the CMC decrease with increasing chainlength of fatty acid constituent of the soap molecule and are in agreement with the values obtained from other micellar properties. The various acoustic parameters (intermolecular freelength, adiabatic compressibility, apparent molar compressibility, specific acoustic impedance, apparent molar volume, molar sound velocity, solvation number, available volume and relative association) for yttrium soaps (myristate, palmitate, stearate and oleate) have been evaluated by ultrasonic velocity measurements. (Authors)

  1. Occupational exposure to organic solvents and risk of male breast cancer

    DEFF Research Database (Denmark)

    Laouali, Nasser; Pilorget, Corinne; Cyr, Diane

    2018-01-01

    models. Results Lifetime cumulative exposure to trichloroethylene >23.9 ppm years was associated with an increased MBC risk, compared to non-exposure [OR (95% CI): 2.1 (1.2-4.0); P trend .... In addition, a possible role for benzene and ethylene glycol in MBC risk was suggested, but no exposure-response trend was observed. Conclusions These findings add to the evidence of an increased risk of breast cancer among men professionally exposed to trichloroethylene and possibly to benzene or ethylene...

  2. Ternary and binary LLE measurements for solvent (2-methyltetrahydrofuran and cyclopentyl methyl ether) + furfural + water between 298 and 343 K

    International Nuclear Information System (INIS)

    Männistö, Mikael; Pokki, Juha-Pekka; Fournis, Ludivine; Alopaeus, Ville

    2017-01-01

    Highlights: • Novel LLE of 2-methyltetrahydrofuran or cyclopentyl methyl ether + furfural + water. • High performance solvents for liquid-liquid extraction exhibited. • Modelled with UNIQUAC-HOC activity coefficient model. • Comparison to other industrial solvents with distribution coefficient and selectivity. - Abstract: The suitability of two solvents for the extraction of furfural from aqueous streams is assessed through novel ternary and binary liquid-liquid equilibria data for mixtures of solvent (2-methyltetrahydrofuran or cyclopentyl methyl ether) + furfural + water. The measured data are reported along with regressed binary interaction parameters for UNIQUAC-HOC activity coefficient model and further analyzed through distribution coefficients and selectivity for furfural. Out of the two solvents, cyclopentyl methyl ether presents a very high selectivity along with good distribution coefficient in the entire temperature range.

  3. Measurement of the quantity of water in organic solvents by infrared absorption an measurement of the dielectric constants

    International Nuclear Information System (INIS)

    Desnoyer, M.

    1959-06-01

    Some chemical methods for the analysis of the quantity of water in solvents are first described, their object being the determination of the maximum error for cases where the water content is less than 1 per cent. - The first part of the work consists in describing infrared spectrometry as applied to the analysis of water in carbon tetrachloride, chloroform aniline, acetone and dioxane. A method based on isotopic exchange between heavy and light water is used on the one hand for determining the solubility of water in carbon tetrachloride and on the other hand for establishing standard solutions (sensitivity of the method). - In the second part the dielectric constant of water solvent solutions is measured. A table is presented giving the precision obtained by the two principal methods. These are comparable and further than that the appearance of the spectra suggests an interpretation of the anomalies observed in calibration curves obtained by the dielectric constant method. (author) [fr

  4. Measurement and Correlation of the Ionic Conductivity of Ionic Liquid-Molecular Solvent Solutions

    Institute of Scientific and Technical Information of China (English)

    LI,Wen-Jing; HAN,Bu-Xing; TAO,Ran-Ting; ZHANG,Zhao-Fu; ZHANG,Jian-Ling

    2007-01-01

    The ionic conductivity of the solutions formed from 1-n-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4]) or 1-n-butyl-3-methylimidazolium hexafluorophosphate ([Bmim][PF6]) and different molecular solvents (MSs) were measured at 298.15 K. The molar conductivity of the ionic liquids (ILs) increased dramatically with increasing concentration of the MSs. It was found that the molar conductivity of the IL in the solutions studied in this work could be well correlated by the molar conductivity of the neat ILs and the dielectric constant and molar volume of the MSs.

  5. A solvent extraction technique for the isotopic measurement of dissolved copper in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Claire M., E-mail: claire.thompson@anu.edu.au; Ellwood, Michael J., E-mail: michael.ellwood@anu.edu.au; Wille, Martin, E-mail: martin.wille@uni-tuebingen.de

    2013-05-02

    Graphical abstract: -- Highlights: •A new sample preparation method for seawater copper isotopic analysis (δ{sup 65}Cu). •Solvent-extraction was used to pre-concentrate metals from seawater samples. •Anion-exchange was used to purify copper from the metal-rich extract. •δ{sup 65}Cu was measured in the north Tasman Sea. •Seawater δ{sup 65}Cu may be linked to marine biological activity. -- Abstract: Stable copper (Cu) isotope geochemistry provides a new perspective for investigating and understanding Cu speciation and biogeochemical Cu cycling in seawater. In this work, sample preparation for isotopic analysis employed solvent-extraction with amino pyrollidine dithiocarbamate/diethyl dithiocarbamate (APDC/DDC), coupled with a nitric acid back-extraction, to concentrate Cu from seawater. This was followed by Cu-purification using anion-exchange. This straightforward technique is high yielding and fractionation free for Cu and allows precise measurement of the seawater Cu isotopic composition using multi-collector inductively coupled plasma mass-spectrometry. A deep-sea profile measured in the oligotrophic north Tasman Sea shows fractionation in the Cu isotopic signature in the photic zone but is relatively homogenised at depth. A minima in the Cu isotopic profile correlates with the chlorophyll a maximum at the site. These results indicate that a range of processes are likely to fractionate stable Cu isotopes in seawater.

  6. Experimental measurement and modelling of solubility of inosine-5′-monophosphate disodium in pure and mixed solvents

    International Nuclear Information System (INIS)

    Zou, Fengxia; Zhuang, Wei; Wu, Jinglan; Zhou, Jingwei; Liu, Qiyan; Chen, Yong; Xie, Jingjing; Zhu, Chenjie; Guo, Ting; Ying, Hanjie

    2014-01-01

    Graphical abstract: - Highlights: • Solubility of 5′-IMPNa 2 in various solvents was studied for the first time. • The solubility could be ranked as follows: water > methanol > ethanol > acetone. • Modified Apelblat equation gave the best correlating results. • Mixing Gibbs free energies, enthalpies, and entropies were predicted. • Solubility data and equations can optimise the crystallization conditions. - Abstract: The solubility of biological chemicals in solvents provide important fundamental data and is generally considered as an essential factor in the design of crystallization processes. The equilibrium solubility data of inosine-5′-monophosphate disodium (5′-IMPNa 2 ) in water, methanol, ethanol, acetone, as well as in the solvent mixtures (methanol + water, ethanol + water, acetone + water), were measured by an isothermal method at temperatures ranging from (293.15 to 313.15) K. The measured data in pure and mixed solvents were then modelled using the modified Apelblat equation, van’t Hoff equation, λh equation, ideal model and the Wilson model. The modified Apelblat equation showed the best modelling results, and it was therefore used to predict the mixing Gibbs free energies, enthalpies, and entropies of 5′-IMPNa 2 in pure and binary solvents. The positive values of the calculated partial molar Gibbs free energies indicated the variations in the solubility trends of 5′-IMPNa 2 . Water and ethanol (in the binary mixture with water) were found to be the most effective solvent and anti-solvent, respectively

  7. Solvent substitutes

    International Nuclear Information System (INIS)

    Evanoff, S.P.

    1995-01-01

    The environmental and industrial hygiene regulations promulgated since 1980, most notably the Superfund Amendments and Reauthorization Act (SARA), the Hazardous and Solid Waste Amendments to the Resources Conservation and Recovery Act (RCRA), and the Clean Air Act Amendments of 1990, have brought about an increased emphasis on user exposure, hazardous waste generation, and air emissions. As a result, industry is performing a fundamental reassessment of cleaning solvents, processes, and procedures. The more progressive organizations have made their goal the elimination of solvents that may pose significant potential human health and environmental hazards. This chapter discusses solvent cleaning in metal-finishing, metal-manufacturing, and industrial maintenance applications; precision cleaning; and electronics manufacturing. Nonmetallic cleaning, adhesives, coatings, inks, and aerosols also will be addressed, but in a more cursory manner

  8. In situ measurement of solvent-mediated phase transformations during dissolution testing

    DEFF Research Database (Denmark)

    Aaltonen, Jaakko; Heinänen, Paula; Peltonen, Leena

    2006-01-01

    In this study, solvent-mediated phase transformations of theophylline (TP) and nitrofurantoin (NF) were measured in a channel flow intrinsic dissolution test system. The test set-up comprised simultaneous measurement of drug concentration in the dissolution medium (with UV-Vis spectrophotometry......) and measurement of the solid-state form of the dissolving solid (in situ with Raman spectroscopy). The solid phase transformations were also investigated off-line with scanning electron microscopy. TP anhydrate underwent a transformation to TP monohydrate, and NF anhydrate (form beta) to NF monohydrate (form II......). Transformation of TP anhydrate to TP monohydrate resulted in a clear decrease in the dissolution rate, while the transformation of NF anhydrate (form beta) to NF monohydrate (form II) could not be linked as clearly to changes in the dissolution rate. The transformation of TP was an order of magnitude faster than...

  9. Density and speed of sound of lithium bromide with organic solvents: Measurement and correlation

    Energy Technology Data Exchange (ETDEWEB)

    Zafarani-Moattar, Mohammed Taghi [Department of Physical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz 51664 (Iran, Islamic Republic of); Research Institute of Fundamental Sciences, Tabriz 51664 (Iran, Islamic Republic of)], E-mail: zafarani47@yahoo.com; Shekaari, Hemayat [Department of Physical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz 51664 (Iran, Islamic Republic of); Research Institute of Fundamental Sciences, Tabriz 51664 (Iran, Islamic Republic of)

    2007-12-15

    Densities, {rho}, and speed of sound, u, of the solutions of LiBr with non-aqueous solvents (methanol, ethanol, 2-propanol, acetone, and acetonitrile) having a wide range of dielectric constants were measured at T = 298.15 K. Also, these measurements were made for the system (LiBr + N,N-dimethylacetamide) at T = 323.15 K. For the investigated systems, the limiting values for apparent molar volume, V{sub {phi}}{sup 0}, and the apparent molar isentropic compressibility, {kappa}{sub {phi}}{sup 0}, were obtained from the Redlich-Mayer and an abbreviated form of the Pitzer equations. The Pitzer and NRTL equations were satisfactorily used for the correlation of apparent molar volumes, V{sub {phi}}, and the apparent molar isentropic compressibility, {kappa}{sub {phi}}, values of the studied systems.

  10. Solvent Extraction Separation of Phosphorus for the Measurement of {sup 32}P

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sang Hoon; Lee, Heung N.; Ahn, Hong Joo; Han, Sun ho; Jee, Kwang Yong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2006-07-01

    Phosphorus is a major element in life and plays essential roles in the human body. On the other hand, phosphorus organic compound has high toxicity, therefore, the determination of trace amount of phosphorus is important in environment studies. Development of an analytical method for the determination of low levels of phosphorus is very important as a very few analytical techniques yield reliable results for this element at trace levels. Radioactive phosphorus, {sup 32}P (T1/2 = 14.3 d, Emax 1.71 MeV) is the highest energy beta-emitting radionuclides and now generally accepted as an effective therapeutic agent for chronic leukemia and excess red blood cells. But, {sup 32}P used in diagnosis and treatment are generated radioactive waste such as pipette tips, latex gloves, angioplastic balloons, Kimwipes etc.. We'll analyze {sup 32}P in medical radioactive waste in the future. Even if {sup 32}P has low level activity and short halflife, we have to control radioactive materials in medical waste. In this work, experiment separation using solvent extraction of inactive phosphorus as preliminary experiments for the establishment of analysis. Phosphorus is extracted tri-n-octylamine (TNOA)/ xylene, which is the most suitable solvent and then is measured by UV-visable spectrophotometer.

  11. Solvent Extraction Separation of Phosphorus for the Measurement of 32P

    International Nuclear Information System (INIS)

    Kang, Sang Hoon; Lee, Heung N.; Ahn, Hong Joo; Han, Sun ho; Jee, Kwang Yong

    2006-01-01

    Phosphorus is a major element in life and plays essential roles in the human body. On the other hand, phosphorus organic compound has high toxicity, therefore, the determination of trace amount of phosphorus is important in environment studies. Development of an analytical method for the determination of low levels of phosphorus is very important as a very few analytical techniques yield reliable results for this element at trace levels. Radioactive phosphorus, 32 P (T1/2 = 14.3 d, Emax 1.71 MeV) is the highest energy beta-emitting radionuclides and now generally accepted as an effective therapeutic agent for chronic leukemia and excess red blood cells. But, 32 P used in diagnosis and treatment are generated radioactive waste such as pipette tips, latex gloves, angioplastic balloons, Kimwipes etc.. We'll analyze 32 P in medical radioactive waste in the future. Even if 32 P has low level activity and short halflife, we have to control radioactive materials in medical waste. In this work, experiment separation using solvent extraction of inactive phosphorus as preliminary experiments for the establishment of analysis. Phosphorus is extracted tri-n-octylamine (TNOA)/ xylene, which is the most suitable solvent and then is measured by UV-visable spectrophotometer

  12. Measurement of dielectric constant of organic solvents by indigenously developed dielectric probe

    Science.gov (United States)

    Keshari, Ajay Kumar; Rao, J. Prabhakar; Rao, C. V. S. Brahmmananda; Ramakrishnan, R.; Ramanarayanan, R. R.

    2018-04-01

    The extraction, separation and purification of actinides (uranium and plutonium) from various matrices are an important step in nuclear fuel cycle. One of the separation process adopted in an industrial scale is the liquid-liquid extraction or solvent extraction. Liquid-liquid extraction uses a specific ligand/extractant in conjunction with suitable diluent. Solvent extraction or liquid-liquid extraction, involves the partitioning of the solute between two immiscible phases. In most cases, one of the phases is aqueous, and the other one is an organic solvent. The solvent used in solvent extraction should be selective for the metal of interest, it should have optimum distribution ratio, and the loaded metal from the organic phase should be easily stripped under suitable experimental conditions. Some of the important physical properties which are important for the solvent are density, viscosity, phase separation time, interfacial surface tension and the polarity of the extractant.

  13. Measurement of Radiofrequency Radiation Exposure in Epidemiological Studies (invited paper)

    International Nuclear Information System (INIS)

    Swerdlow, A.J.

    1999-01-01

    The measurement of radiofrequency (RF) exposure is important to the quality of epidemiological studies of the possible association of RF exposure with disease. The extent and type of exposure measurement in past epidemiological studies of RF, and the features of measurement that would be desirable for better studies in the future are summarised. Measurement characteristics that are discussed include quantification of radiation frequency and of intensity and timing of exposures, measurement (or good estimation) of exposures for individuals rather than only for groups, quality of measurement, and measurement of RF exposures experienced outside the study setting. Integration of exposure measurement into the design of epidemiological studies is needed for better assessments of possible RF effects. (author)

  14. Solvent sorption measurements in polymeric membranes with ATR-IR spectroscopy

    NARCIS (Netherlands)

    Manito Pereira, A.M.; Lopes, M.C.; Timmer, J.M.K.; Keurentjes, J.T.F.

    2005-01-01

    Long-term stability and performance of polymeric membranes in solvent and mixed solvent media can be reduced due to sorption and swelling of the membrane matrix. For this reason quantification of sorption and swelling is of major importance for the development of future applications of membrane

  15. Permeability of commercial solvents through living human skin

    DEFF Research Database (Denmark)

    Ursin, C; Hansen, C M; Van Dyk, J W

    1995-01-01

    A procedure has been developed for measuring the steady state rate of permeation of commercial solvents through living human skin. To get the most consistent results, it was necessary with some solvents to normalize the solvent permeation rate of a given skin sample with its [3H]water permeation...... rate. For other solvents this was not necessary, so the un-normalized data were used. High [3H]water permeation rate also was used as a criterion for "defective" skin samples that gave erroneous permeability rates, especially for solvents having slow permeability. The linearity of the steady state data...... of DMSO and octyl acetate were measured. No octyl acetate was detected and the permeability of DMSO was proportional to its mole fraction in the mixture. The effect of two hours of solvent exposure on the viability of skin (based on DNA synthesis) was measured and found to be very dependent on the solvent....

  16. Effect of solvent and temperature on the size distribution of casein micelles measured by dynamic light scattering.

    Science.gov (United States)

    Beliciu, C M; Moraru, C I

    2009-05-01

    The objectives of this study were to investigate the effect of the solvent on the accuracy of casein micelle particle size determination by dynamic light scattering (DLS) at different temperatures and to establish a clear protocol for these measurements. Dynamic light scattering analyses were performed at 6, 20, and 50 degrees C using a 90Plus Nanoparticle Size Analyzer (Brookhaven Instruments, Holtsville, NY). Raw and pasteurized skim milk were used as sources of casein micelles. Simulated milk ultrafiltrate, ultrafiltered water, and permeate obtained by ultrafiltration of skim milk using a 10-kDa cutoff membrane were used as solvents. The pH, ionic concentration, refractive index, and viscosity of all solvents were determined. The solvents were evaluated by DLS to ensure that they did not have a significant influence on the results of the particle size measurements. Experimental protocols were developed for accurate measurement of particle sizes in all solvents and experimental conditions. All measurements had good reproducibility, with coefficients of variation below 5%. Both the solvent and the temperature had a significant effect on the measured effective diameter of the casein micelles. When ultrafiltered permeate was used as a solvent, the particle size and polydispersity of casein micelles decreased as temperature increased. The effective diameter of casein micelles from raw skim milk diluted with ultrafiltered permeate was 176.4 +/- 5.3 nm at 6 degrees C, 177.4 +/- 1.9 nm at 20 degrees C, and 137.3 +/- 2.7 nm at 50 degrees C. This trend was justified by the increased strength of hydrophobic bonds with increasing temperature. Overall, the results of this study suggest that the most suitable solvent for the DLS analyses of casein micelles was casein-depleted ultrafiltered permeate. Dilution with water led to micelle dissociation, which significantly affected the DLS measurements, especially at 6 and 20 degrees C. Simulated milk ultrafiltrate seemed to give

  17. Apparatus to measure adsorption of condensable solvents on technical surfaces by photothermal deflection

    Science.gov (United States)

    Plimmer, M. D.; du Colombier, D.; Iraqi Houssaini, N.; Silvestri, Z.; Pinot, P.; Hannachi, R.

    2012-11-01

    This article describes an instrument for the measurement of the mirage effect as a tool to determine the molar adsorption per unit surface area Y1 of condensable solvents in the presence of a non-condensable carrier gas. The present apparatus is a much improved version of previous prototypes developed in our laboratory and elsewhere with a higher surface bake-out temperature (150 °C rather than 40 °C), lower residual vacuum (3 Pa versus 100 Pa), greater sample surface (40 mm diameter instead of 10 mm), more powerful optical pump beam (150 W cf. 50 W), and larger saturated vapour preparation volume (4 L instead of 1 L). The new set-up also includes the in situ monitoring of the surface via a reflected HeNe laser beam for the real-time detection of the onset of condensation. Here, we give a detailed description of the various components, outline the experimental procedure, show typical results, and suggest some straightforward improvements.

  18. Application of microbial biomass and activity measures to assess in situ bioremediation of chlorinated solvents

    International Nuclear Information System (INIS)

    Phelps, T.J.; Herbes, S.E.; Palumbo, A.V.; Pfiffner, S.M.; Mackowski, R.; Ringelberg, D.; White, D.C.; Tennessee Univ., Knoxville, TN

    1993-01-01

    Evaluating the effectiveness of chlorinated solvent remediation in the subsurface can be a significant problem given uncertainties in estimating the total mass of contaminants present. If the remediation technique is a biological activity, information on the progress and success of the remediation may be gained by monitoring changes in the mass and activities of microbial populations. The in situ bioremediation demonstration at the US Department of Energy (DOE) Savannah River Site (SRS) is designed to test the effectiveness of methane injection for the stimulation of in sediments. Past studies have shown the potential for degradation by native microbial populations. The design and implementation of the SRS Integrated Demonstration is described in this volume. A control phase without treatment was followed by a phase withdrawing air. The next phase included vacuum extraction plus air injection into the lower horizontal well located below the water table. The next period included the injection of 1% methane in air followed by injection of 4% methane in air. Based on the literature, it was hypothesized that the injection of methane would stimulate methanotrophic populations and thus accelerate biological degradation of TCE. Measuring the success of bioremediation is a complex effort that includes monitoring of changes in microbial populations associated with TCE degradation. These monitoring efforts are described in this paper and in related papers in this volume

  19. Measurements and correlation of viscosities and conductivities for the mixtures of ethylammonium nitrate with organic solvents

    International Nuclear Information System (INIS)

    Litaeim, Yousra; Zarrougi, Ramzi; Dhahbi, Mahmoud

    2009-01-01

    Room temperature ionic liquids (IL) as a new class of organic molten salts have been considered as an alternative of traditional organic solvents (OS). The physico-chemical transport properties of mixtures IL/OS were investigated and described by ion-ion, ion solvent and solvent-solvent interactions. Ethylammonium nitrate (EAN) was studied in presence of two types of organic solvents: the dimethyl carbonate (DMC) and the formamide (FA). The variation of the viscosity with salt concentration and temperature shows that EAN ions behave as a structure breaker for the DMC. However, no effect was recorded in the case of FA. Concentrated electrolyte solutions behave as very structured media and checked a theory of pseudo-lattice. The existence of a conductivity maximum indicates two competing effects; the increasing number of charge carriers and the higher viscosity of the electrolyte as the salt concentration was raised. The use of the Walden product to investigate ionic interactions of EAN with both solvents was discussed. A study of the effect of temperature on the conductivity and viscosity reveals that both systems (EAN/DMC and EAN/FA) obey an Arrhenius low. The activation energies for the tow transport process (Ea,L and Ea,h) as a function of the salt concentration were evaluated.

  20. External exposure measurements at Bikini Atoll

    International Nuclear Information System (INIS)

    Greenhouse, N.A.; Miltenberger, R.P.; Lessard, E.T.

    1979-01-01

    External exposure rate surveys from 1975 to 1977 on the islands Nam, Eneu and Bikini of Bikini Atoll gave average external exposure rates of 24, 5.7, and 32 μR/hr respectively. The exposure rate on Eneu Island is uniform, whereas those on Bikini and Nam range from 7.0 to 80. μR/hr. Based on an assumed living pattern at Bikini Island, the adult male Bikinian is estimated to be in the presence of an external radiation field corresponding to 16 μR/hr due to debris and fallout from the 1954 BRAVO incident. This corresponds to a 30 year dose equivalent of 2.8 rem

  1. Effect of physical exertion on the biological monitoring of exposure of various solvents following exposure by inhalation in human volunteers: I. Toluene.

    Science.gov (United States)

    Nadeau, Véronique; Truchon, Ginette; Brochu, Martin; Tardif, Robert

    2006-09-01

    Physical exertion (work load) has been recognized as one of several factors that can influence the kinetics of xenobiotics within the human body. This study was undertaken to evaluate the impact of physical exertion on two exposure indicators of toluene (TOL) in human volunteers exposed under controlled conditions in an inhalation chamber. A group of four volunteers (one woman, three men) were exposed to TOL (50 ppm) according to the following scenarios involving several periods during which volunteers were asked to perform either aerobic (AERO), muscular (MUSC), or both (AERO/MUSC) types of physical exercise (exercise bicycle, treadmills, pulleys). The target intensities (W) for each exercising period of 30 min--interspaced with 15 min at rest--were the following: REST, 50 W AERO (time-weighted average intensity [TWAI]: 46 watts); 50 W AERO/MUSC (TWAI: 38 watts) and 100 W AERO (TWAI: 71 watts) for 7 hours and 50 W MUSC for 3 hours (TWAI: 29 watts). Alveolar air and urine samples were collected at different time intervals before, during, and after exposure for the measurement of unchanged TOL in expired air (TOL-A) and urinary o-cresol (o-CR). Overall, the results showed that TOL-A measured during and after all scenarios involving physical activities were higher (approximately 1.4-2.0 fold) compared with exposures at rest. All scenarios involving physical exertion also resulted in increased end-of-exposure urinary o-CR (mean +/- SD): 0.9 +/- 0.1 mg/L (REST) vs. 2.0 +/- 0.1 mg/L (TWAI 46 watts). However, exposure at a TWAI of 71 watts did not further increase o-CR excretion (1.7 +/- 0.2 mg/L). This study confirms the significant effect of work load on TOL kinetics and showed that o-CR excretion increased proportionally with work load expressed as TWAI or with the estimated mean pulmonary ventilation during the period of exposure. This study also shows that exposure to TOL (50 ppm) involving a work load of around 50 W (light intensity) or lower is likely to produce

  2. Temperature dependence measurements and structural characterization of trimethyl ammonium ionic liquids with a highly polar solvent.

    Science.gov (United States)

    Attri, Pankaj; Venkatesu, Pannuru; Hofman, T

    2011-08-25

    We report the synthesis and characterization of a series of an ammonium ionic liquids (ILs) containing acetate, dihydrogen phosphate, and hydrogen sulfate anions with a common cation. To characterize the thermophysical properties of these newly synthesized ILs with the highly polar solvent N,N-dimethylformamide (DMF), precise measurements such as densities (ρ) and ultrasonic sound velocities (u) over the whole composition range have been performed at atmospheric pressure and over wide temperature ranges (25-50 °C). The excess molar volume (V(E)) and the deviation in isentropic compressibilities (Δκ(s)) were predicted using these temperature dependence properties as a function of the concentration of ILs. The Redlich-Kister polynomial was used to correlate the results. The ILs investigated in the present study included trimethylammonium acetate [(CH(3))(3)NH][CH(3)COO] (TMAA), trimethylammonium dihydrogen phosphate [(CH(3))(3)NH][H(2)PO(4)] (TMAP), and trimethylammonium hydrogen sulfate [(CH(3))(3)NH][HSO(4)] (TMAS). The intermolecular interactions and structural effects were analyzed on the basis of the measured and the derived properties. In addition, the hydrogen bonding between ILs and DMF has been demonstrated using semiempirical calculations with help of Hyperchem 7. A qualitative analysis of the results is discussed in terms of the ion-dipole, ion-pair interactions, and hydrogen bonding between ILs and DMF molecules and their structural factors. The influence of the anion of the protic IL, namely, acetate (CH(3)COO), dihydrogen phosphate (H(2)PO(4)), and hydrogen sulfate (HSO(4)), on the thermophysical properties is also provided. © 2011 American Chemical Society

  3. Measurement of residual solvents in a drug substance by a purge-and-trap method.

    Science.gov (United States)

    Lakatos, Miklós

    2008-08-05

    The purge-and-trap (P&T) gas extraction method combined with gas chromatography was studied for its suitability for quantitative residual solvents determination in a water-soluble active pharmaceutical ingredient (API). Some analytical method performance characteristics were investigated, namely, the repeatability, the accuracy and the detection limit of determination. The results show that the P&T technique is--as expected--more sensitive than the static headspace, thus it can be used for the determination of residual solvents pertaining to the ICH Class 1 group. It was found that it could be an alternative sample preparation method besides the static headspace (HS) method.

  4. Estimators for longitudinal latent exposure models: examining measurement model assumptions.

    Science.gov (United States)

    Sánchez, Brisa N; Kim, Sehee; Sammel, Mary D

    2017-06-15

    Latent variable (LV) models are increasingly being used in environmental epidemiology as a way to summarize multiple environmental exposures and thus minimize statistical concerns that arise in multiple regression. LV models may be especially useful when multivariate exposures are collected repeatedly over time. LV models can accommodate a variety of assumptions but, at the same time, present the user with many choices for model specification particularly in the case of exposure data collected repeatedly over time. For instance, the user could assume conditional independence of observed exposure biomarkers given the latent exposure and, in the case of longitudinal latent exposure variables, time invariance of the measurement model. Choosing which assumptions to relax is not always straightforward. We were motivated by a study of prenatal lead exposure and mental development, where assumptions of the measurement model for the time-changing longitudinal exposure have appreciable impact on (maximum-likelihood) inferences about the health effects of lead exposure. Although we were not particularly interested in characterizing the change of the LV itself, imposing a longitudinal LV structure on the repeated multivariate exposure measures could result in high efficiency gains for the exposure-disease association. We examine the biases of maximum likelihood estimators when assumptions about the measurement model for the longitudinal latent exposure variable are violated. We adapt existing instrumental variable estimators to the case of longitudinal exposures and propose them as an alternative to estimate the health effects of a time-changing latent predictor. We show that instrumental variable estimators remain unbiased for a wide range of data generating models and have advantages in terms of mean squared error. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Effect of physical exertion on the biological monitoring of exposure to various solvents following exposure by inhalation in human volunteers: II. n-Hexane.

    Science.gov (United States)

    Tardif, Robert; Nadeau, Véronique; Truchon, Ginette; Brochu, Martin

    2007-07-01

    This study evaluated the impact of physical exertion on two n-hexane (HEX) exposure indicators in human volunteers exposed under controlled conditions in an inhalation chamber. A group of four volunteers (two women, two men) were exposed to HEX (50 ppm; 176 mg/m(3)) according to several scenarios involving several periods when volunteers performed either aerobic (AERO), muscular (MUSC), or both AERO/MUSC types of exercise. The target intensities for 30-min exercise periods separated by 15-min rest periods were the following: REST, 50W AERO [time-weighted average intensity including resting period (TWAI): 38W], 50W AERO/MUSC (TWAI: 34W), 100W AERO/MUSC (TWAI: 63W), and 100W AERO (TWAI: 71W) for 7 hr (two 3-hr exposure periods separated by 1 hr without exposure) and 50W MUSC for 3 hr (TWAI: 31W). Alveolar air and urine samples were collected at different time intervals before, during, and after exposure to measure unchanged HEX in expired air (HEX-A) and urinary 2,5-hexanedione (2,5-HD). HEX-A levels during exposures involving AERO activities (TWAI: 38W and 71W) were significantly enhanced (approximately +14%) compared with exposure at rest. MUSC or AERO/MUSC exercises were also associated with higher HEX-A levels but only at some sampling times. In contrast, end-of-exposure (7 hr) urinary 2,5-HD (mean +/- SD) was not modified by physical exertion: 4.14 +/- 1.51 micromol/L (REST), 4.02 +/- 1.52 micromol/L (TWAI 34W), 4.25 +/- 1.53 micromol/L (TWAI 38W), 3.73 +/- 2.09 micromol/L (TWAI 63W), 3.6 +/- 1.34 micromol/L (TWAI 71W) even though a downward trend was observed. Overall, this study showed that HEX kinetics is practically insensitive to moderate variations in workload intensity; only HEX-A levels increased slightly, and urinary 2,5-HD levels remained unchanged despite the fact that all types of physical exercise increased the pulmonary ventilation rate.

  6. Protective measures during construction against radon exposure

    International Nuclear Information System (INIS)

    Horn, W.

    1990-01-01

    Radon, thoron as well as their daughter products have an cancerogeneous effect on the human respiratory tracts. In this respect protective measures in the area of construction are of great importance. This article deals with constructional solutions which consist of different individual measures. Sources of radon are outside air, water, fuels, building materials as well as the building ground. Possible protective measures are divided into area-related (floor structure, intermediate floors, exterior walls of cellar, foundation slab, building ground), line-related (joints, cracks, wall ducts) as well as supplementary measures (tightly closing doors, arrangement of natural cross-ventilation and vertical ventilating shafts). (BWI) [de

  7. Measurement and correlation of solubilities of apigenin and apigenin 7-O-rhamnosylglucoside in seven solvents at different temperatures

    International Nuclear Information System (INIS)

    Xiao Min; Shao Yundong; Yan Weidong; Zhang Zizhang

    2011-01-01

    The solubilities of apigenin and apigenin 7-O-rhamnosylglucoside in water, methanol, ethanol, 1-propanol, 1-butanol, acetone, and ethyl acetate from T = (288.2 to 328.2) K were measured. The solubilities of apigenin and apigenin 7-O-rhamnosylglucoside in selected solvents increase with increasing temperature, respectively. The experimental solubility data were correlated by a simplified thermodynamic equation and a three-parameter empirical equation.

  8. Drone based measurement system for radiofrequency exposure assessment.

    Science.gov (United States)

    Joseph, Wout; Aerts, Sam; Vandenbossche, Matthias; Thielens, Arno; Martens, Luc

    2016-03-10

    For the first time, a method to assess radiofrequency (RF) electromagnetic field (EMF) exposure of the general public in real environments with a true free-space antenna system is presented. Using lightweight electronics and multiple antennas placed on a drone, it is possible to perform exposure measurements. This technique will enable researchers to measure three-dimensional RF-EMF exposure patterns accurately in the future and at locations currently difficult to access. A measurement procedure and appropriate measurement settings have been developed. As an application, outdoor measurements are performed as a function of height up to 60 m for Global System for Mobile Communications (GSM) 900 MHz base station exposure. Bioelectromagnetics. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. Solvents Measurement and Influence on health in the Work Environment in Manufacturing

    Directory of Open Access Journals (Sweden)

    piia tint

    2015-09-01

    Full Text Available The composition of the mixture of chemicals in the work environment depends mostly on the temperature of the air or processing temperature of the raw material or the intermediate products. For determination the chemicals in the air FTIR/FT-NIR spectrometer Interspec 301-X with open optical path and Dräger tubes were used. The toxicology of the gaseous components was determined on the basis of the scientific literature. On the basis of these investigations and the legislation on the chemicals safety (exposure limits the health risk assessment model (HRA was worked out. This model connects the hazards in the work environment and the health risk to the workers and also gives the possibility to the medical personnel to determine the frequency of the medical examinations and biomonitoring for the workers continuously working in the hazardous conditions. The novelty of the study includes in the possibility to keep under control the chemicals concentration in the work environment air through the use of HRA model and the measurement with modern measurement equipment (FTIR/FT-NIR. DOI: http://dx.doi.org/10.5755/j01.ms.21.3.7345

  10. Confounding and exposure measurement error in air pollution epidemiology.

    Science.gov (United States)

    Sheppard, Lianne; Burnett, Richard T; Szpiro, Adam A; Kim, Sun-Young; Jerrett, Michael; Pope, C Arden; Brunekreef, Bert

    2012-06-01

    Studies in air pollution epidemiology may suffer from some specific forms of confounding and exposure measurement error. This contribution discusses these, mostly in the framework of cohort studies. Evaluation of potential confounding is critical in studies of the health effects of air pollution. The association between long-term exposure to ambient air pollution and mortality has been investigated using cohort studies in which subjects are followed over time with respect to their vital status. In such studies, control for individual-level confounders such as smoking is important, as is control for area-level confounders such as neighborhood socio-economic status. In addition, there may be spatial dependencies in the survival data that need to be addressed. These issues are illustrated using the American Cancer Society Cancer Prevention II cohort. Exposure measurement error is a challenge in epidemiology because inference about health effects can be incorrect when the measured or predicted exposure used in the analysis is different from the underlying true exposure. Air pollution epidemiology rarely if ever uses personal measurements of exposure for reasons of cost and feasibility. Exposure measurement error in air pollution epidemiology comes in various dominant forms, which are different for time-series and cohort studies. The challenges are reviewed and a number of suggested solutions are discussed for both study domains.

  11. Measuring the relative hydrogen-bonding strengths of alcohols in aprotic organic solvents.

    Science.gov (United States)

    Tessensohn, Malcolm E; Lee, Melvyn; Hirao, Hajime; Webster, Richard D

    2015-01-12

    Voltammetric experiments with 9,10-anthraquinone and 1,4-benzoquinone performed under controlled moisture conditions indicate that the hydrogen-bond strengths of alcohols in aprotic organic solvents can be differentiated by the electrochemical parameter ΔEp (red) =|Ep (red(1)) -Ep (red(2)) |, which is the potential separation between the two one-electron reduction processes. This electrochemical parameter is inversely related to the strength of the interactions and can be used to differentiate between primary, secondary, tertiary alcohols, and even diols, as it is sensitive to both their steric and electronic properties. The results are highly reproducible across two solvents with substantially different hydrogen-bonding properties (CH3 CN and CH2 Cl2 ) and are supported by density functional theory calculations. This indicates that the numerous solvent-alcohol interactions are less significant than the quinone-alcohol hydrogen-bonding interactions. The utility of ΔEp (red) was illustrated by comparisons between 1) 3,3,3-trifluoro-n-propanol and 1,3-difluoroisopropanol and 2) ethylene glycol and 2,2,2-trifluoroethanol. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Measurement of infinite dilution activity coefficient and application of modified ASOG model for solvent-polymer systems

    Energy Technology Data Exchange (ETDEWEB)

    Choi, B.; Choi, J. [Kwangwoon University, Seoul (Korea, Republic of); Tochigi, K.; Kojima, K. [Nihon University, Tokyo (Japan)

    1996-04-20

    A gas chromatographic method was used in order to measure vapor-liquid equilibria for solvent (1)-polymer (2) systems in which the polymers were polystyrene, poly(a-methyl) styrene and the advents were benzene toluene cyclohexane methylisobutylketone, ethylacetate, and vinylacetate. The activity coefficients of solvents for solvent (1)-polymer (2) systems were measured at infinite dilution and the modified ASOG (Analytical Solution of Group) model was suggested to describe vapor-liquid equilibria of those systems within a range of temperatures 423.15K through 498.15K. The model consists of the original ASOG and the free volume term. An external degree of freedom in the free volume term empirically became to a C1={alpha}+{beta}/T as a function of temperature. Each tern in the modified ASOG model is based on the weight fraction. The external degree of freedom in the model was estimated by experimental data within a range of temperatures. As a result of doing it the infinite dilution activity coefficients calculated were agreed with the experimental data within an error of 0.1%. 27 refs., 3 figs., 7 tabs.

  13. Solvent effects on the antioxidant capacity of lipophilic and hydrophilic antioxidants measured by CUPRAC, ABTS/persulphate and FRAP methods.

    Science.gov (United States)

    Celik, Saliha Esin; Ozyürek, Mustafa; Güçlü, Kubilay; Apak, Reşat

    2010-06-15

    Antioxidants are health beneficial compounds that can protect cells and macromolecules (e.g., fats, lipids, proteins, and DNA) from the damage of reactive oxygen species (ROS). Solvent effect is a crucial parameter on the chemical behaviour of antioxidant compounds but there has been limited information regarding its role on antioxidant capacity and its assays. Therefore, the present study was undertaken to investigate the total antioxidant capacity (TAC) of some certain lipophilic and hydrophilic antioxidants, measured in different solvent media such as ethanol (EtOH) (100%), methanol (MeOH) (100%), methanol/water (4:1, v/v), methanol/water (1:1, v/v), dichloromethane (DCM)/EtOH (9:1, v/v). The cupric reducing antioxidant capacity (CUPRAC) values of selected antioxidants were experimentally reported in this work as trolox equivalent antioxidant capacity (TEAC), and compared to those found by reference TAC assays, i.e., 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)/persulphate (ABTS/persulphate) and ferric reducing antioxidant power (FRAP) methods. The TAC values of synthetic mixtures of antioxidants were experimentally measured as trolox equivalents and compared to those theoretically found by making use of the principle of additivity of absorbances assuming no chemical interaction between the mixture constituents. Possible synergistic (e.g., BHT and BHA in DCM/EtOH) or antagonistic behaviours of these synthetic mixtures were investigated in relation to solvent selection.

  14. Measuring and modeling exposure from environmental radiation on tidal flats

    International Nuclear Information System (INIS)

    Gould, T.J.; Hess, C.T.

    2005-01-01

    To examine the shielding effects of the tide cycle, a high pressure ion chamber was used to measure the exposure rate from environmental radiation on tidal flats. A theoretical model is derived to predict the behavior of exposure rate as a function of time for a detector placed one meter above ground on a tidal flat. The numerical integration involved in this derivation results in an empirical formula which implies exposure rate ∝tan-1(sint). We propose that calculating the total exposure incurred on a tidal flat requires measurements of only the slope of the tidal flat and the exposure rate when no shielding occurs. Experimental results are consistent with the model

  15. Measurement Error Correction for Predicted Spatiotemporal Air Pollution Exposures.

    Science.gov (United States)

    Keller, Joshua P; Chang, Howard H; Strickland, Matthew J; Szpiro, Adam A

    2017-05-01

    Air pollution cohort studies are frequently analyzed in two stages, first modeling exposure then using predicted exposures to estimate health effects in a second regression model. The difference between predicted and unobserved true exposures introduces a form of measurement error in the second stage health model. Recent methods for spatial data correct for measurement error with a bootstrap and by requiring the study design ensure spatial compatibility, that is, monitor and subject locations are drawn from the same spatial distribution. These methods have not previously been applied to spatiotemporal exposure data. We analyzed the association between fine particulate matter (PM2.5) and birth weight in the US state of Georgia using records with estimated date of conception during 2002-2005 (n = 403,881). We predicted trimester-specific PM2.5 exposure using a complex spatiotemporal exposure model. To improve spatial compatibility, we restricted to mothers residing in counties with a PM2.5 monitor (n = 180,440). We accounted for additional measurement error via a nonparametric bootstrap. Third trimester PM2.5 exposure was associated with lower birth weight in the uncorrected (-2.4 g per 1 μg/m difference in exposure; 95% confidence interval [CI]: -3.9, -0.8) and bootstrap-corrected (-2.5 g, 95% CI: -4.2, -0.8) analyses. Results for the unrestricted analysis were attenuated (-0.66 g, 95% CI: -1.7, 0.35). This study presents a novel application of measurement error correction for spatiotemporal air pollution exposures. Our results demonstrate the importance of spatial compatibility between monitor and subject locations and provide evidence of the association between air pollution exposure and birth weight.

  16. Assigning exposure to pesticides and solvents from self-reports collected by a computer assisted personal interview and expert assessment of job codes: the UK Adult Brain Tumour Study.

    Science.gov (United States)

    Hepworth, S J; Bolton, A; Parslow, R C; van Tongeren, M; Muir, K R; McKinney, P A

    2006-04-01

    To compare assignment of occupational pesticide and solvent exposure using self-reported data collected by a computer assisted personal interview (CAPI) with exposure based on expert assessment of job codes. To discuss the advantages and disadvantages of using a CAPI to collect individual occupational exposure data. Between 2001 and 2004, 1495 participants were interviewed using a CAPI for a case-control study of adult brain tumours and acoustic neuromas. Two types of occupational data were collected: (1) a full history, including job title from which a job code was assigned from the Standard Occupational Classification; and (2) specific details on pesticide and solvent exposure reported by participants. Study members' experiences of using the CAPI were recorded and advantages and disadvantages summarised. Of 7192 jobs recorded, the prevalence of self-reported exposure was 1.3% for pesticides and 11.5% for solvents. Comparing this with exposure expertly assessed from job titles showed 53.6% and 45.8% concordance for pesticides and solvents respectively. Advantages of the CAPI include no data entry stage, automatic input validation, and a reduction in interviewer bias. Disadvantages include an adverse effect on study implementation as a consequence of resources required for programming and difficulties encountered with data management prior to analysis. Different methods of exposure assessment derive different exposure levels for pesticide and solvent exposure at work. Agreement between self-reported and expert assessment of exposure was greater for pesticides compared to solvents. The advantages of using a CAPI for the collection of complex data outweigh the disadvantages for interviewers and data quality but using such a method requires extra resources at the study outset.

  17. Assigning exposure to pesticides and solvents from self‐reports collected by a computer assisted personal interview and expert assessment of job codes: the UK Adult Brain Tumour Study

    Science.gov (United States)

    Hepworth, S J; Bolton, A; Parslow, R C; van Tongeren, M; Muir, K R; McKinney, P A

    2006-01-01

    Objectives To compare assignment of occupational pesticide and solvent exposure using self‐reported data collected by a computer assisted personal interview (CAPI) with exposure based on expert assessment of job codes. To discuss the advantages and disadvantages of using a CAPI to collect individual occupational exposure data. Methods Between 2001 and 2004, 1495 participants were interviewed using a CAPI for a case‐control study of adult brain tumours and acoustic neuromas. Two types of occupational data were collected: (1) a full history, including job title from which a job code was assigned from the Standard Occupational Classification; and (2) specific details on pesticide and solvent exposure reported by participants. Study members' experiences of using the CAPI were recorded and advantages and disadvantages summarised. Results Of 7192 jobs recorded, the prevalence of self‐reported exposure was 1.3% for pesticides and 11.5% for solvents. Comparing this with exposure expertly assessed from job titles showed 53.6% and 45.8% concordance for pesticides and solvents respectively. Advantages of the CAPI include no data entry stage, automatic input validation, and a reduction in interviewer bias. Disadvantages include an adverse effect on study implementation as a consequence of resources required for programming and difficulties encountered with data management prior to analysis. Conclusions Different methods of exposure assessment derive different exposure levels for pesticide and solvent exposure at work. Agreement between self‐reported and expert assessment of exposure was greater for pesticides compared to solvents. The advantages of using a CAPI for the collection of complex data outweigh the disadvantages for interviewers and data quality but using such a method requires extra resources at the study outset. PMID:16556747

  18. Simple Apparatus for the Measurement of Total Pressure of Polymer + Solvent Mixtures.

    Czech Academy of Sciences Publication Activity Database

    Pavlíček, Jan; Bogdanić, Grozdana; Wichterle, Ivan

    2017-01-01

    Roč. 40, č. 5 (2017), s. 991-996 ISSN 0930-7516. [International Congress of Chemical and Process Engineering CHISA 2016 /22./ and the 19th Conference PRES 2016. Prague, 27.08.2016-31.08.2016] R&D Projects: GA ČR GA15-19542S Institutional support: RVO:67985858 Keywords : vapor-liquid equilibrium * polymer-solvent systems * static cells Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 2.051, year: 2016

  19. Personal radiofrequency electromagnetic field exposure measurements in Swiss adolescents.

    Science.gov (United States)

    Roser, Katharina; Schoeni, Anna; Struchen, Benjamin; Zahner, Marco; Eeftens, Marloes; Fröhlich, Jürg; Röösli, Martin

    2017-02-01

    Adolescents belong to the heaviest users of wireless communication devices, but little is known about their personal exposure to radiofrequency electromagnetic fields (RF-EMF). The aim of this paper is to describe personal RF-EMF exposure of Swiss adolescents and evaluate exposure relevant factors. Furthermore, personal measurements were used to estimate average contributions of various sources to the total absorbed RF-EMF dose of the brain and the whole body. Personal exposure was measured using a portable RF-EMF measurement device (ExpoM-RF) measuring 13 frequency bands ranging from 470 to 3600MHz. The participants carried the device for three consecutive days and kept a time-activity diary. In total, 90 adolescents aged 13 to 17years participated in the study conducted between May 2013 and April 2014. In addition, personal measurement values were combined with dose calculations for the use of wireless communication devices to quantify the contribution of various RF-EMF sources to the daily RF-EMF dose of adolescents. Main contributors to the total personal RF-EMF measurements of 63.2μW/m 2 (0.15V/m) were exposures from mobile phones (67.2%) and from mobile phone base stations (19.8%). WLAN at school and at home had little impact on the personal measurements (WLAN accounted for 3.5% of total personal measurements). According to the dose calculations, exposure from environmental sources (broadcast transmitters, mobile phone base stations, cordless phone base stations, WLAN access points, and mobile phones in the surroundings) contributed on average 6.0% to the brain dose and 9.0% to the whole-body dose. RF-EMF exposure of adolescents is dominated by their own mobile phone use. Environmental sources such as mobile phone base stations play a minor role. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. #2 - An Empirical Assessment of Exposure Measurement Error ...

    Science.gov (United States)

    Background• Differing degrees of exposure error acrosspollutants• Previous focus on quantifying and accounting forexposure error in single-pollutant models• Examine exposure errors for multiple pollutantsand provide insights on the potential for bias andattenuation of effect estimates in single and bipollutantepidemiological models The National Exposure Research Laboratory (NERL) Human Exposure and Atmospheric Sciences Division (HEASD) conducts research in support of EPA mission to protect human health and the environment. HEASD research program supports Goal 1 (Clean Air) and Goal 4 (Healthy People) of EPA strategic plan. More specifically, our division conducts research to characterize the movement of pollutants from the source to contact with humans. Our multidisciplinary research program produces Methods, Measurements, and Models to identify relationships between and characterize processes that link source emissions, environmental concentrations, human exposures, and target-tissue dose. The impact of these tools is improved regulatory programs and policies for EPA.

  1. Directly measured secondhand smoke exposure and COPD health outcomes

    Directory of Open Access Journals (Sweden)

    Balmes John

    2006-06-01

    Full Text Available Abstract Background Although personal cigarette smoking is the most important cause and modulator of chronic obstructive pulmonary disease (COPD, secondhand smoke (SHS exposure could influence the course of the disease. Despite the importance of this question, the impact of SHS exposure on COPD health outcomes remains unknown. Methods We used data from two waves of a population-based multiwave U.S. cohort study of adults with COPD. 77 non-smoking respondents with a diagnosis of COPD completed direct SHS monitoring based on urine cotinine and a personal badge that measures nicotine. We evaluated the longitudinal impact of SHS exposure on validated measures of COPD severity, physical health status, quality of life (QOL, and dyspnea measured at one year follow-up. Results The highest level of SHS exposure, as measured by urine cotinine, was cross-sectionally associated with poorer COPD severity (mean score increment 4.7 pts; 95% CI 0.6 to 8.9 and dyspnea (1.0 pts; 95% CI 0.4 to 1.7 after controlling for covariates. In longitudinal analysis, the highest level of baseline cotinine was associated with worse COPD severity (4.7 points; 95% CI -0.1 to 9.4; p = 0.054, disease-specific QOL (2.9 pts; -0.16 to 5.9; p = 0.063, and dyspnea (0.9 pts; 95% CI 0.2 to 1.6 pts; p Conclusion Directly measured SHS exposure appears to adversely influence health outcomes in COPD, independent of personal smoking. Because SHS is a modifiable risk factor, clinicians should assess SHS exposure in their patients and counsel its avoidance. In public health terms, the effects of SHS exposure on this vulnerable subpopulation provide a further rationale for laws prohibiting public smoking.

  2. Psychomotor Effects of Mixed Organic Solvents on Rubber Workers

    Directory of Open Access Journals (Sweden)

    O Aminian

    2014-04-01

    Full Text Available Background: Exposure to organic solvents is common among workers. Objective: To assess neurobehavioral effects of long-term exposure to organic solvents among rubber workers in Tehran, Iran. Methods: Across-sectional study was conducted on 223 employees of a rubber industry. The participants completed a data collection sheet on their occupational and medical history, and demographic characteristics including age, work experience, education level; they performed 6 psychiatric tests on the neurobehavioral core test battery (NCTB that measure simple reaction time, short-term memory (digit span, Benton, eye-hand coordination (Purdue pegboard, pursuit aiming, and perceptual speed (digit symbol. Results: Workers exposed and not exposed to organic solvents had similar age and education distribution. The mean work experience of the exposed and non-exposed workers was 5.9 and 4.4 years, respectively. The exposed workers had a lower performance compared to non-exposed workers in all psychomotor tests. After controlling for the confounders by logistic regression analysis, it was found that exposure to organic solvents had a significant effect on the results of digit symbols, digit span, Benton, aiming, and simple reaction time tests. No significant effect was observed in pegboard test. Conclusion: Occupational exposure to organic solvent can induce subtle neurobehavioral changes among workers exposed to organic solvents; therefore, periodical evaluation of the central nervous system by objective psychomotor tests is recommended among those who are chronically exposed to organic solvents.

  3. Comparison of magnetic field meters used for Elf exposure measurement

    International Nuclear Information System (INIS)

    Magne, I.; Azoulay, A.; Lambrozo, J.; Souques, M.

    2006-01-01

    Objective The question of the biological effects of E.L.F. electromagnetic fields (50/60 Hz) has lead to many experimental and epidemiological works, in occupational exposure and in residential exposure. One of the main difficulties is to integrate the maximum of information about the environmental exposures during the everyday life without limitation to the exposure of the home. The objective of this study is to analyse experimentally the metrology associated with human exposure to 50 Hz magnetic field, in the optic of a study of the French population exposure. Method 4 meters were tested: the E.M.D.E.X. II, currently used in epidemiological studies, the E.M.D.E.X. L.I.T.E., which is more recent, the H.T.300, an Italian meter, and the F.D.3, which is made by Combinova A calibration was performed with an Helmoltz coil. The immunity of these meters to GSM signal was also tested. The influence of the sample rate was evaluated. Results and conclusion The meter chosen for performing the measurements of the exposure study will be selected in function of the following criteria: - easiness of use - precision - low sample rate - memory size and reliability of data stocking - immunity to GSM perturbations. (authors)

  4. Effect of physical exertion on the biological monitoring of exposure to various solvents following exposure by inhalation in human volunteers: III. Styrene.

    Science.gov (United States)

    Truchon, Ginette; Brochu, Martin; Tardif, Robert

    2009-08-01

    This study evaluated the impact of different work load intensities on biological indicators of styrene exposure. Four adult Caucasian men, aged 20 to 44 years, were recruited. Groups of 2-4 volunteers were exposed to 20 ppm of styrene in an exposure chamber according to scenarios involving either aerobic, muscular, or both types of physical exercise for 3 or 7 hr. The target intensities for each 30-min exercise period-interspaced with 15 min at rest-were the following: REST, 38 watts AERO (time-weighted average intensity), 34 watts AERO/MUSC, 49 watts AERO/MUSC, and 54 watts AERO for 7 hr and 22 watts MUSC for 3 hr. End-exhaled air samples were collected at 15 time points during and after 7-hr exposures for the determination of styrene concentrations. Urine samples were collected before the start of exposure, after the first 3 hr of exposure, and at the end of exposure for the determination of mandelic acid (MA) and phenylglyoxilic acid (PGA) concentrations. Compared with exposure at rest, styrene in alveolar air increased by a factor up to 1.7, while the sum of urinary MA and PGA increased by a factor ranging from 1.2 to 3.5, depending on the exposure scenario. Concentrations of biological indicators of styrene fluctuated with physical exertion and were correlated with the magnitude of the physical activity and pulmonary ventilation. Despite the physical exertion effect, urinary concentrations of styrene metabolites after a single-day exposure remain below the current biological exposure index value recommended by ACGIH; therefore, no additional health risk is expected. However, results shows that work load intensities must be considered in the interpretation of biological monitoring data and in the evaluation of the health risk associated with styrene exposure.

  5. Miniature nanoparticle sensors for exposure measurement and TEM sampling

    International Nuclear Information System (INIS)

    Fierz, Martin; Meier, Dominik; Steigmeier, Peter; Burtscher, Heinz

    2015-01-01

    Nanoparticles in workplaces may pose a threat to the health of the workers involved. With the general boom in nanotechnology, an increasing number of workers is potentially exposed, and therefore a comprehensive risk management with respect to nanoparticles appears necessary. One (of many) components of such a risk management is the measurement of personal exposure. Traditional nanoparticle detectors are often cumbersome to use, large, heavy and expensive. We have developed small, reliable and easy to use devices that can be used for routine personal exposure measurement in workplaces. (paper)

  6. Solvent extraction

    Energy Technology Data Exchange (ETDEWEB)

    Coombs, D.M.; Latimer, E.G.

    1988-01-05

    It is an object of this invention to provide for the demetallization and general upgrading of heavy oil via a solvent extracton process, and to improve the efficiency of solvent extraction operations. The yield and demetallization of product oil form heavy high-metal content oil is maximized by solvent extractions which employ either or all of the following techniques: premixing of a minor amount of the solvent with feed and using countercurrent flow for the remaining solvent; use of certain solvent/free ratios; use of segmental baffle tray extraction column internals and the proper extraction column residence time. The solvent premix/countercurrent flow feature of the invention substantially improves extractions where temperatures and pressures above the critical point of the solvent are used. By using this technique, a greater yield of extract oil can be obtained at the same metals content or a lower metals-containing extract oil product can be obtained at the same yield. Furthermore, the premixing of part of the solvent with the feed before countercurrent extraction gives high extract oil yields and high quality demetallization. The solvent/feed ratio features of the invention substanially lower the captial and operating costs for such processes while not suffering a loss in selectivity for metals rejection. The column internals and rsidence time features of the invention further improve the extractor metals rejection at a constant yield or allow for an increase in extract oil yield at a constant extract oil metals content. 13 figs., 3 tabs.

  7. Confounding and exposure measurement error in air pollution epidemiology

    NARCIS (Netherlands)

    Sheppard, L.; Burnett, R.T.; Szpiro, A.A.; Kim, J.Y.; Jerrett, M.; Pope, C.; Brunekreef, B.|info:eu-repo/dai/nl/067548180

    2012-01-01

    Studies in air pollution epidemiology may suffer from some specific forms of confounding and exposure measurement error. This contribution discusses these, mostly in the framework of cohort studies. Evaluation of potential confounding is critical in studies of the health effects of air pollution.

  8. ACREM: A new air crew radiation exposure measuring system

    International Nuclear Information System (INIS)

    Beck, P.; Duftschmid, K.; Kerschbaumer, S.; Schmitzer, C.; Strachotinsky, C.; Grosskopf, A.; Winkler, N.

    1996-01-01

    Cosmic radiation has already been discovered in 1912 by the Austrian Nobel Laureate Victor F. Hess. After Hess up to now numerous measurements of the radiation exposure by cosmic rays in different altitudes have been performed, however, this has not been taken serious in view of radiation protection.Today, with the fast development of modern airplanes, an ever increasing number of civil aircraft is flying in increasing altitudes for considerable time. Members of civil aircrew spending up to 1000 hours per year in cruising altitudes and therefore are subject to significant levels of radiation exposure. In 1990 ICRP published its report ICRP 60 with updated excess cancer risk estimates, which led to significantly higher risk coefficients for some radiation qualities. An increase of the radiation weighting factors for mean energy neutron radiation increases the contribution for the neutron component to the equivalent dose by about 60%, as compared to the earlier values of ICRP26. This higher risk coefficients lead to the recommendation of the ICRP, that cosmic radiation exposure in civil aviation should be taken into account as occupational exposure. Numerous recent exposure measurements at civil airliners in Germany, Sweden, USA, and Russia show exposure levels in the range of 3-10 mSv/year. This is significantly more than the average annual dose of radiation workers (in Austria about 1.5 mSv/year). Up to now no practicable and economic radiation monitoring system for routine application on board exits. A fairly simple and economic approach to a practical, active in-flight dosimeter for the assessment of individual crew exposure is discussed in this paper

  9. 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...

  10. Does occupational exposure to solvents and pesticides in association with glutathione S-transferase A1, M1, P1, and T1 polymorphisms increase the risk of bladder cancer? The Belgrade case-control study.

    Directory of Open Access Journals (Sweden)

    Marija G Matic

    Full Text Available OBJECTIVE: We investigated the role of the glutathione S-transferase A1, M1, P1 and T1 gene polymorphisms and potential effect modification by occupational exposure to different chemicals in Serbian bladder cancer male patients. PATIENTS AND METHODS: A hospital-based case-control study of bladder cancer in men comprised 143 histologically confirmed cases and 114 age-matched male controls. Deletion polymorphism of glutathione S-transferase M1 and T1 was identified by polymerase chain reaction method. Single nucleotide polymorphism of glutathione S-transferase A1 and P1 was identified by restriction fragment length polymorphism method. As a measure of effect size, odds ratio (OR with corresponding 95% confidence interval (95%CI was calculated. RESULTS: The glutathione S-transferase A1, T1 and P1 genotypes did not contribute independently toward the risk of bladder cancer, while the glutathione S-transferase M1-null genotype was overrepresented among cases (OR = 2.1, 95% CI = 1.1-4.2, p = 0.032. The most pronounced effect regarding occupational exposure to solvents and glutathione S-transferase genotype on bladder cancer risk was observed for the low activity glutathione S-transferase A1 genotype (OR = 9.2, 95% CI = 2.4-34.7, p = 0.001. The glutathione S-transferase M1-null genotype also enhanced the risk of bladder cancer among subjects exposed to solvents (OR = 6,5, 95% CI = 2.1-19.7, p = 0.001. The risk of bladder cancer development was 5.3-fold elevated among glutathione S-transferase T1-active patients exposed to solvents in comparison with glutathione S-transferase T1-active unexposed patients (95% CI = 1.9-15.1, p = 0.002. Moreover, men with glutathione S-transferase T1-active genotype exposed to pesticides exhibited 4.5 times higher risk in comparison with unexposed glutathione S-transferase T1-active subjects (95% CI = 0.9-22.5, p = 0.067. CONCLUSION: Null or low-activity genotypes of the

  11. Standardizing measurement, sampling and reporting for public exposure assessments

    Energy Technology Data Exchange (ETDEWEB)

    Rochedo, Elaine R.R. [Instituto de Radioprotecao e Dosimetria, Comissao Nacional de Energia Nuclear, Av. Salvador Allende s/No. CEP 22780-160 Rio de Janeiro, RJ (Brazil)], E-mail: elaine@ird.gov.br

    2008-11-15

    UNSCEAR assesses worldwide public exposure from natural and man-made sources of ionizing radiation based on information submitted to UNSCEAR by United Nations Member States and from peer reviewed scientific literature. These assessments are used as a basis for radiation protection programs of international and national regulatory and research organizations. Although UNSCEAR describes its assessment methodologies, the data are based on various monitoring approaches. In order to reduce uncertainties and improve confidence in public exposure assessments, it would be necessary to harmonize the methodologies used for sampling, measuring and reporting of environmental results.

  12. Radiation exposure in nuclear medicine: real-time measurement

    International Nuclear Information System (INIS)

    Sylvain, Iara; Bok, Bernard; X. Bichat University, Paris

    2002-01-01

    French regulations have introduced the use of electronic dosimeters for personnel monitoring of workers. In order to evaluate the exposure from diagnostic procedures to nuclear medicine staff, individual whole-body doses were measured daily with electronic (digital) personal dosimeters during 20 consecutive weeks and correlated with the work load of each day. Personal doses remained always below 20 mu Sv/d under normal working conditions. Radiation exposure levels were highest to tech staff, nurses and stretcher-bearers. The extrapolated annual cumulative doses for all staff remained less than 10% of the maximum legal limit for exposed workers (2 mSv/yr). Electronic dosimeters are not technically justified for routine survey of staff. The high sensitivity and immediate reading of electronic semiconductor dosimeters may become very useful for exposure control under risky working conditions. It may become an important help for optimising radiation protection. (author)

  13. Improving the accuracy of smart devices to measure noise exposure.

    Science.gov (United States)

    Roberts, Benjamin; Kardous, Chucri; Neitzel, Richard

    2016-11-01

    Occupational noise exposure is one of the most frequent hazards present in the workplace; up to 22 million workers have potentially hazardous noise exposures in the U.S. As a result, noise-induced hearing loss is one of the most common occupational injuries in the U.S. Workers in manufacturing, construction, and the military are at the highest risk for hearing loss. Despite the large number of people exposed to high levels of noise at work, many occupations have not been adequately evaluated for noise exposure. The objective of this experiment was to investigate whether or not iOS smartphones and other smart devices (Apple iPhones and iPods) could be used as reliable instruments to measure noise exposures. For this experiment three different types of microphones were tested with a single model of iPod and three generations of iPhones: the internal microphones on the device, a low-end lapel microphone, and a high-end lapel microphone marketed as being compliant with the International Electrotechnical Commission's (IEC) standard for a Class 2-microphone. All possible combinations of microphones and noise measurement applications were tested in a controlled environment using several different levels of pink noise ranging from 60-100 dBA. Results were compared to simultaneous measurements made using a Type 1 sound level measurement system. Analysis of variance and Tukey's honest significant difference (HSD) test were used to determine if the results differed by microphone or noise measurement application. Levels measured with external microphones combined with certain noise measurement applications did not differ significantly from levels measured with the Type 1 sound measurement system. Results showed that it may be possible to use iOS smartphones and smart devices, with specific combinations of measurement applications and calibrated external microphones, to collect reliable, occupational noise exposure data under certain conditions and within the limitations of the

  14. Deasphalting solvents

    International Nuclear Information System (INIS)

    Carrillo, J. A; Caceres, J; Vela, G; Bueno, H

    1996-01-01

    This paper describes how the deasphalted oil (DMO) or demetalized oil (DMO) quality (CCR, Ni, V end asphaltenes contents) changes with: DAO or DMO yield, solvent/feed ratio, type of vacuum reside (from paraffinic to blends with vis breaking bottoms), extraction temperature and extraction solvent (propane, propylene, n-butane and I butane)

  15. Comparison of electric field exposure measurement methods under power lines

    International Nuclear Information System (INIS)

    Korpinen, L.; Kuisti, H.; Tarao, H.; Paeaekkoenen, R.; Elovaara, J.

    2014-01-01

    The object of the study was to investigate extremely low frequency (ELF) electric field exposure measurement methods under power lines. The authors compared two different methods under power lines: in Method A, the sensor was placed on a tripod; and Method B required the measurer to hold the meter horizontally so that the distance from him/her was at least 1.5 m. The study includes 20 measurements in three places under 400 kV power lines. The authors used two commercial three-axis meters, EFA-3 and EFA-300. In statistical analyses, they did not find significant differences between Methods A and B. However, in the future, it is important to take into account that measurement methods can, in some cases, influence ELF electric field measurement results, and it is important to report the methods used so that it is possible to repeat the measurements. (authors)

  16. 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

  17. Study of cellulase enzymes self-assembly in aqueous-acetonitrile solvent: Viscosity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ghaouar, N., E-mail: naoufel-ghaouar@lycos.co [Laboratoire de Physique de la Matiere Molle, Faculte des Sciences de Tunis, Campus Universitaire, 2092 (Tunisia); Institut National des Sciences Appliquees et de Technologie, INSAT, Centre Urbain Nord, BP. 676, Tunis (Tunisia); Aschi, A. [Laboratoire de Physique de la Matiere Molle, Faculte des Sciences de Tunis, Campus Universitaire, 2092 (Tunisia); Belbahri, L. [School of Engineering of Lullier, University of Applied Sciences of Western Switzerland, 150, Route de Presinge, 1254 Jussy (Switzerland); Trabelsi, S.; Gharbi, A. [Laboratoire de Physique de la Matiere Molle, Faculte des Sciences de Tunis, Campus Universitaire, 2092 (Tunisia)

    2009-11-15

    The present study extends the viscosity measurements performed by Ghaouar et al. [Physica B, submitted for publication.] to study the conformational change of the cellulase enzymes in aqueous-acetonitrile mixture. We aim to investigate: (i) the denaturation process by measuring the specific viscosity for temperatures varying between 25 and 65 deg. C and acetonitrile concentrations between 0% and 50%, (ii) the enzyme-enzyme interaction by calculating the Huggins coefficient and (iii) the enzyme sizes by following the hydrodynamic radius for various temperatures. The precipitation of cellulases versus acetonitrile concentration is also considered. We show from all physical quantities measured in this work that the precipitation and the denaturation processes of cellulase enzymes exist together.

  18. Study of cellulase enzymes self-assembly in aqueous-acetonitrile solvent: Viscosity measurements

    International Nuclear Information System (INIS)

    Ghaouar, N.; Aschi, A.; Belbahri, L.; Trabelsi, S.; Gharbi, A.

    2009-01-01

    The present study extends the viscosity measurements performed by Ghaouar et al. [Physica B, submitted for publication.] to study the conformational change of the cellulase enzymes in aqueous-acetonitrile mixture. We aim to investigate: (i) the denaturation process by measuring the specific viscosity for temperatures varying between 25 and 65 deg. C and acetonitrile concentrations between 0% and 50%, (ii) the enzyme-enzyme interaction by calculating the Huggins coefficient and (iii) the enzyme sizes by following the hydrodynamic radius for various temperatures. The precipitation of cellulases versus acetonitrile concentration is also considered. We show from all physical quantities measured in this work that the precipitation and the denaturation processes of cellulase enzymes exist together.

  19. Solvent substitution

    International Nuclear Information System (INIS)

    1990-01-01

    The DOE Environmental Restoration and Waste Management Office of Technology Development and the Air Force Engineering and Services Center convened the First Annual International Workshop on Solvent Substitution on December 4--7, 1990. The primary objectives of this joint effort were to share information and ideas among attendees in order to enhance the development and implementation of required new technologies for the elimination of pollutants associated with industrial use of hazardous and toxic solvents; and to aid in accelerating collaborative efforts and technology transfer between government and industry for solvent substitution. There were workshop sessions focusing on Alternative Technologies, Alternative Solvents, Recovery/Recycling, Low VOC Materials and Treatment for Environmentally Safe Disposal. The 35 invited papers presented covered a wide range of solvent substitution activities including: hardware and weapons production and maintenance, paint stripping, coating applications, printed circuit boards, metal cleaning, metal finishing, manufacturing, compliance monitoring and process control monitoring. This publication includes the majority of these presentations. In addition, in order to further facilitate information exchange and technology transfer, the US Air Force and DOE solicited additional papers under a general ''Call for Papers.'' These papers, which underwent review and final selection by a peer review committee, are also included in this combined Proceedings/Compendium. For those involved in handling, using or managing hazardous and toxic solvents, this document should prove to be a valuable resource, providing the most up-to-date information on current technologies and practices in solvent substitution. Individual papers are abstracted separated

  20. Solvent substitution

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The DOE Environmental Restoration and Waste Management Office of Technology Development and the Air Force Engineering and Services Center convened the First Annual International Workshop on Solvent Substitution on December 4--7, 1990. The primary objectives of this joint effort were to share information and ideas among attendees in order to enhance the development and implementation of required new technologies for the elimination of pollutants associated with industrial use of hazardous and toxic solvents; and to aid in accelerating collaborative efforts and technology transfer between government and industry for solvent substitution. There were workshop sessions focusing on Alternative Technologies, Alternative Solvents, Recovery/Recycling, Low VOC Materials and Treatment for Environmentally Safe Disposal. The 35 invited papers presented covered a wide range of solvent substitution activities including: hardware and weapons production and maintenance, paint stripping, coating applications, printed circuit boards, metal cleaning, metal finishing, manufacturing, compliance monitoring and process control monitoring. This publication includes the majority of these presentations. In addition, in order to further facilitate information exchange and technology transfer, the US Air Force and DOE solicited additional papers under a general Call for Papers.'' These papers, which underwent review and final selection by a peer review committee, are also included in this combined Proceedings/Compendium. For those involved in handling, using or managing hazardous and toxic solvents, this document should prove to be a valuable resource, providing the most up-to-date information on current technologies and practices in solvent substitution. Individual papers are abstracted separated.

  1. Diffusivity measurements in some organic solvents by a gas-liquid diaphragm cell

    NARCIS (Netherlands)

    Littel, R.J.; Littel, R.J.; Versteeg, Geert; van Swaaij, Willibrordus Petrus Maria

    1992-01-01

    A diaphragm cell has been developed for the measurement of diffusion coefficients of gases In liquids. The diaphragm cell is operated batchwise with respect to both gas and liquid phases, and the diffusion process Is followed by means of the gas pressure decrease which is recorded by means of a

  2. Diffusivity Measurements in Some Organic Solvents by a Gas-Liquid Diaphragm Cell

    NARCIS (Netherlands)

    Littel, Rob J.; Versteeg, Geert F.; Swaaij, Wim P.M. van

    1992-01-01

    A diaphragm cell has been developed for the measurement of diffusion coefficients of gases in liquids. The diaphragm cell is operated batchwise with respect to both gas and liquid phases, and the diffusion process is followed by means of the gas pressure decrease which is recorded by means of a

  3. Hydrodynamic radii of polyethylene glycols in different solvents determined from viscosity measurements

    NARCIS (Netherlands)

    Dohmen-Speelmans, M.P.J.; Pereira, A.M.; Timmer, J.M.K.; Benes, N.E.; Keurentjes, J.T.F.

    2008-01-01

    The hydrodynamic radius, rh, of low molar mass polyethylene glycol, MPEG = (200 to 1000) g·mol-1, in a homologous series of primary alcohols, acetone, and toluene has been determined from viscosity measurements. The viscosity data have been collected using a fast one-point method as well as a more

  4. The fear of food measure: a novel measure for use in exposure therapy for eating disorders.

    Science.gov (United States)

    Levinson, Cheri A; Byrne, Meghan

    2015-04-01

    Exposure therapy for mealtime anxiety has preliminarily been effective at increasing food intake and decreasing anxiety in individuals with anorexia nervosa (AN). To enhance our knowledge of exposure therapy for AN researchers and clinicians need a comprehensive measure that assesses outcomes relevant to exposure therapy for AN. In the current four studies we developed Fear of Food Measure (FOFM) that assesses three cognitive and behavioral outcomes: trait anxiety about eating, food avoidance behaviors, and feared concerns related to eating. In a community (N = 399) and undergraduate female sample (N = 203) the FOFM exhibited a good three-factor structure and convergent and divergent validity. In a sample of women (N = 72) we showed that the anxiety about eating subscale significantly predicted in vivo food intake over and above other established predictors of eating (e.g., restraint). In a clinical sample diagnosed with an eating disorder (N = 41) we showed that anxiety about eating was associated with food intake and anxiety during an exposure meal and that all subscales of the FOFM significantly decreased over the course of a four-session exposure intervention. Finally, we found that participants diagnosed with an eating disorder had higher levels of fear of food than did matched controls (N = 23). The FOFM is a psychometrically valid measure that can assess if patients are improving while undergoing exposure therapy and could be used to pinpoint problematic behaviors that can be addressed in exposure therapy. © 2014 Wiley Periodicals, Inc.

  5. Reference value standards and primary standards for pH measurements in D2O and aqueous-organic solvent mixtures: new accessions and assessments

    International Nuclear Information System (INIS)

    Mussini, P.R.; Mussini, T.; Rondinini, S.

    1997-01-01

    Recommended Reference Value Standards based on the potassium hydro-genphthalate buffer at various temperatures are reported for pH measurements in various binary solvent mixtures of water with eight organic solvents: methanol, ethanol, 2-propanol, 1,2-ethanediol, 2-methoxyethanol (''methylcellosolve''), acetonitrile, 1,4-dioxane, and dimethyl sulfoxide, together with Reference Value Standard based on the potassium deuterium phthalate buffer for pD measurements in D 2 O. In addition are reported Primary Standards for pH based on numerous buffers in various binary solvent mixtures of water with methanol, ethanol, and dimethyl sulfoxide, together with Primary Standards for pD in D 2 O based on the citrate, phosphate and carbonate buffers. (author)

  6. An inexpensive instrument for measuring wave exposure and water velocity

    Science.gov (United States)

    Figurski, J.D.; Malone, D.; Lacy, J.R.; Denny, M.

    2011-01-01

    Ocean waves drive a wide variety of nearshore physical processes, structuring entire ecosystems through their direct and indirect effects on the settlement, behavior, and survivorship of marine organisms. However, wave exposure remains difficult and expensive to measure. Here, we report on an inexpensive and easily constructed instrument for measuring wave-induced water velocities. The underwater relative swell kinetics instrument (URSKI) is a subsurface float tethered by a short (<1 m) line to the seafloor. Contained within the float is an accelerometer that records the tilt of the float in response to passing waves. During two field trials totaling 358 h, we confirmed the accuracy and precision of URSKI measurements through comparison to velocities measured by an in situ acoustic Doppler velocimeter and those predicted by a standard swell model, and we evaluated how the dimensions of the devices, its buoyancy, and sampling frequency can be modified for use in a variety of environments.

  7. Exposure to traffic pollution: comparison between measurements and a model.

    Science.gov (United States)

    Alili, F; Momas, I; Callais, F; Le Moullec, Y; Sacre, C; Chiron, M; Flori, J P

    2001-01-01

    French researchers from the Building Scientific and Technical Center have produced a traffic-exposure index. To achieve this, they used an air pollution dispersion model that enabled them to calculate automobile pollutant concentrations in front of subjects' residences and places of work. Researchers used this model, which was tested at 27 Paris canyon street sites, and compared nitrogen oxides measurements obtained with passive samplers during a 6-wk period and calculations derived from the model. There was a highly significant correlation (r = .83) between the 2 series of values; their mean concentrations were not significantly different. The results suggested that the aforementioned model could be a useful epidemiological tool for the classification of city dwellers by present-or even cumulative exposure to automobile air pollution.

  8. Measurements for assessing the exposure from 3G femtocells.

    Science.gov (United States)

    Boursianis, Achilles; Vanias, Pantelis; Samaras, Theodoros

    2012-06-01

    Femtocells are low-power access points, which combine mobile and broadband technologies. The main operation of a femtocell is to function as a miniature base station unit in an indoor environment and to connect to the operator's network through a broadband phone line or a coaxial cable line. This study provides the first experimental measurements and results in Greece for the assessment of exposure to a femtocell access point (FAP) indoors. Using a mobile handset with the appropriate software, power level measurements of the transmitted (Tx) and the received by the mobile handset signal were performed in two different and typical (home and office) environments. Moreover, radiofrequency electric field strength and frequency selective measurements with a radiation meter (SRM-3000) were carried out in the proximity of the FAP installation point. The cumulative distribution functions of the Tx power at most cases (except one) show that in 90% of all points the power of the mobile phone was lower by at least 7 dB during FAP operation. At a distance of ∼1 m from the FAP (in its main beam), power flux density measurements show that there is very little difference between the two situations (FAP ON and OFF). As a conclusion, the use of femtocells indoors improves reception quality, reduces the Tx power of the user's mobile terminal and results in an indiscernible increase of the electromagnetic field in front of the unit, at values that are extremely low compared with reference levels of exposure guidelines.

  9. Measurement of 90Sr radioactivity in a rapid method of strontium estimation by solvent extraction with dicarbollides

    International Nuclear Information System (INIS)

    Svoboda, K.; Kyrs, M.

    1994-01-01

    The application of liquid scintillation counting to the measurement of 90 Sr radioactivity was studied, using a previously published rapid method of strontium separation, based on solvent extraction with a solution of cobalt dicarbollide and Slovafol 909 in a nitrobenzene-carbon tetrachloride mixture and subsequent stripping of strontium with a 0.15 M Chelaton IV (CDTA) solution at pH 10.2. With liquid scintillation counting, a more efficient elimination of the effect of 90 Y β-activity on 90 Sr counting is possible than when measuring the evaporated aliquot with the use of a solid scintillator. The adverse effect of traces of dicarbollide, nitrobenzene, and CCl 4 passed over in the aqueous 90 Sr solution prepared for counting, is caused by the (poorly reproducible) shift of the 90 Sr + 90 Y β-radiation spectral curve towards lower energies, the so-called quenching. The shift is independent of the aqueous phase concentration of the organic compounds mentioned. They can be removed by shaking the aqueous reextract with an equal volume of octanol or amyl acetate so that the undesirable spectral shift does not occur. No loss of strontium was found in this washing procedure. (author) 2 tabs., 6 figs., 5 refs

  10. Student's music exposure: Full-day personal dose measurements.

    Science.gov (United States)

    Washnik, Nilesh Jeevandas; Phillips, Susan L; Teglas, Sandra

    2016-01-01

    Previous studies have shown that collegiate level music students are exposed to potentially hazardous sound levels. Compared to professional musicians, collegiate level music students typically do not perform as frequently, but they are exposed to intense sounds during practice and rehearsal sessions. The purpose of the study was to determine the full-day exposure dose including individual practice and ensemble rehearsals for collegiate student musicians. Sixty-seven college students of classical music were recruited representing 17 primary instruments. Of these students, 57 completed 2 days of noise dose measurements using Cirrus doseBadge programed according to the National Institute for Occupational Safety and Health criterion. Sound exposure was measured for 2 days from morning to evening, ranging from 7 to 9 h. Twenty-eight out of 57 (49%) student musicians exceeded a 100% daily noise dose on at least 1 day of the two measurement days. Eleven student musicians (19%) exceeded 100% daily noise dose on both days. Fourteen students exceeded 100% dose during large ensemble rehearsals and eight students exceeded 100% dose during individual practice sessions. Approximately, half of the student musicians exceeded 100% noise dose on a typical college schedule. This finding indicates that a large proportion of collegiate student musicians are at risk of developing noise-induced hearing loss due to hazardous sound levels. Considering the current finding, there is a need to conduct hearing conservation programs in all music schools, and to educate student musicians about the use and importance of hearing protection devices for their hearing.

  11. Measurement of the oxidative potential of PM2.5 and its constituents : The effect of extraction solvent and filter type

    NARCIS (Netherlands)

    Yang, Aileen; Jedynska, Aleksandra; Hellack, Bryan; Rooter, Ingeborg; Hoek, Gerard; Brunekreef, Bert; Kuhlbusch, Thomas A. J.; Cassee, Flemming R.; Janssen, Nicole A. H.

    The capacity of Particulate Matter (PM) to oxidise target molecules, defined as its oxidative potential (OP), has been proposed as a biologically more relevant metric than PM mass. Different assays exist for measuring OP and their methodologies vary in the choice of extraction solvent and filter

  12. Ellipsometry-based combination of isothermal sorption-desorption measurement and temperature programmed desorption technique: A probe for interaction of thin polymer films with solvent vapor

    Science.gov (United States)

    Efremov, Mikhail Yu.; Nealey, Paul F.

    2018-05-01

    An environmental chamber equipped with an in situ spectroscopic ellipsometer, programmatic vapor pressure control, and variable temperature substrate holder has been designed for studying polymer coating behavior during an exposure to a solvent vapor and also for probing the residual solvent in the film afterwards. Both sorption-desorption cycle at a constant temperature and temperature programmed desorption (TPD) of the residual solvent manifest themselves as a change of the film thickness. Monitoring of ellipsometric angles of the coating allows us to determine the thickness as a function of the vapor pressure or sample temperature. The solvent vapor pressure is precisely regulated by a computer-controlled pneumatics. TPD spectra are recorded during heating of the film in an oil-free vacuum. The vapor pressure control system is described in detail. The system has been tested on 6-170 nm thick polystyrene, poly(methyl methacrylate), and poly(2-vinyl pyridine) films deposited on silicon substrates. Liquid toluene, water, ethanol, isopropanol, cyclohexane, 1,2-dichloroethane, and chlorobenzene were used to create a vapor atmosphere. Typical sorption-desorption and TPD curves are shown. The instrument achieves sub-monolayer sensitivity for adsorption studies on flat surfaces. Polymer-solvent vapor systems with strong interaction demonstrate characteristic absorption-desorption hysteresis spanning from vacuum to the glass transition pressure. Features on the TPD curves can be classified as either glass transition related film contraction or low temperature broad contraction peak. Typical absorption-desorption and TPD dependencies recorded for the 6 nm thick polystyrene film demonstrate the possibility to apply the presented technique for probing size effects in extremely thin coatings.

  13. Humidity correction in the standard measurement of exposure

    International Nuclear Information System (INIS)

    Ibaraki, Yasuyuki; Katoh, Akira

    1980-01-01

    This paper deals with the humidity correction to be made in the standard measurement of the exposure to the measured ionization current in the humid air for the purpose of excluding the influence of the water vapour that is not included in the definition of the exposure. First, formulae giving the humidity correction factors for a parallel plate free air chamber and a cavity chamber have been derived respectively in the case where the contributions of air and water vapour to the ionization are independent. Next, in the case where the contributions are not independent, i.e., the Jesse effect is taken into account, a formula to obtain the W-value for humid air has been derived on the basis of the Niatel's experimental result. Using this formula, formulae to obtain the humidity correction factors for the free air chamber and the cavity chamber are derived. The humidity calculated by the latter formulae show good agreements with the results by Niatel and Guiho, respectively. (author)

  14. Radiation exposure of patients due to medical measures

    International Nuclear Information System (INIS)

    Schwarz, E.R.; Tsavachidis, C.; Hinz, G.; Eigelsreiter, H.

    1987-01-01

    The main objective of this research project supported by the Federal Ministry of the Interior was to collect the data required as a basis for an up-to-date assessment of the radiation exposure of the population as a result of medical measures. Apart from the fact that this had to be done in order to fulfill a commitment required by the EURATOM principles, the report in hand also presents a useful survey of the improvements achieved over the last years in terms of radiation hygiene in the field of imaging technology applied for medical diagnostics. The data obtained from four hospital centers (2 university hospitals, 1 city hospital, and one county hospital) and from three medical practices (radiologist, internal specialist, orthopedics), the changes experienced in the selection of imaging methods for diagnostic purposes in the period 1976 to 1983 or 1985 are illustrated, and analyses show the developmental trends. The results show that there is reason to assume the radiation exposure of the population to be receding. (orig./MG) [de

  15. Ionic association and solvation of the ionic liquid 1-hexyl-3-methylimidazolium chloride in molecular solvents revealed by vapor pressure osmometry, conductometry, volumetry, and acoustic measurements.

    Science.gov (United States)

    Sadeghi, Rahmat; Ebrahimi, Nosaibah

    2011-11-17

    A systematic study of osmotic coefficient, conductivity, volumetric and acoustic properties of solutions of ionic liquid 1-hexyl-3-methylimidazolium chloride ([C(6)mim][Cl]) in various molecular solvents has been made at different temperatures in order to study of ionic association and solvation behavior of [C(6)mim][Cl] in different solutions. Precise measurements on electrical conductances of solutions of [C(6)mim][Cl] in water, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and acetonitrile at 293.15, 298.15, and 303.15 K are reported and analyzed with Barthel's low-concentration chemical model (lcCM) to obtain the limiting molar conductivities and association constants of this ionic liquid in the investigated solvents. Strong ion pairing was found for the ionic liquid in 2-propanol, 1-butanol, and 1-propanol, whereas ion association in acetonitrile, methanol and ethanol is rather weak and in water the ionic liquid is fully dissociated. In the second part of this work, the apparent molar volumes and isentropic compressibilities of [C(6)mim][Cl] in water, methanol, ethanol, acetonitrile, 1-propanol, 2-propanol, and 1-butanol are obtained at the 288.15-313.15 K temperature range at 5 K intervals at atmospheric pressure from the precise measurements of density and sound velocity. The infinite dilution apparent molar volume and isentropic compressibility values of the free ions and ion pairs of [C(6)mim][Cl] in the investigated solvents as well as the excess molar volume of the investigated solutions are determined and their variations with temperature and type of solvents are also studied. Finally, the experimental measurements of osmotic coefficient at 318.15 K for binary solutions of [C(6)mim][Cl] in water, methanol, ethanol, 2-propanol, and acetonitrile are taken using the vapor pressure osmometry (VPO) method and from which the values of the solvent activity, vapor pressure, activity coefficients, and Gibbs free energies are calculated. The results are

  16. Hair radioactivity as a measure of exposure to radioisotopes

    Science.gov (United States)

    Strain, W. H.; Pories, W. J.; Fratianne, R. B.; Flynn, A.

    1972-01-01

    Since many radioisotopes accumulate in hair, this tropism was investigated by comparing the radioactivity of shaved with plucked hair collected from rats at various time intervals up to 24 hrs after intravenous injection of the ecologically important radioisotopes, iodine-131, manganese-54, strontium-85, and zinc-65. The plucked hair includes the hair follicles where biochemical transformations are taking place. The data indicate a slight surge of each radioisotpe into the hair immediately after injection, a variation of content of each radionuclide in the hair, and a greater accumulation of radioactivity in plucked than in shaved hair. These results have application not only to hair as a measure of exposure to radioisotopes, but also to tissue damage and repair at the hair follicle.

  17. The Effect of Solvent, Hydrogen Peroxide and Dioxide Titanium on Degradation of PCBs, Using Microwave Radiation in Order to Reduce Occupational Exposure

    Directory of Open Access Journals (Sweden)

    Tajik Reza

    2014-07-01

    Full Text Available Polychlorinated biphenyls (PCBs are one group of persistent organic pollutants (POPs that are of international concern because of global distribution, persistence, and toxicity. Removal of these compounds from the environment remains a very difficult challenge because the compounds are highly hydrophobic and have very low solubility in water. A 900 W domestic microwave oven, pyrex vessel reactor, pyrex tube connector and condensing system were used in this experiment. Radiation was discontinuous and ray powers were 540, 720 and 900 W. The PCBS were analyzed by GC-ECD. The application of microwave radiation and H2O2/TiO2 agents for the degradation of polychlorinated biphenyl contaminated oil was explored in this study. PCB – contaminated oil was treated in a pyrex reactor by microwave irradiation at 2450 MHz with the addition of H2O2/TiO2. A novel grain TiO2 (GT01 was used. The determination of PCB residues in oil by gas chromatography (GC revealed that rates of PCB decomposition were highly dependent on microwave power, exposure time, ratio to solvent with transformer oil in 3:1, the optimal amount of GT01 (0.2 g and 0.116 mol of H2O2 were used in the study. It was suggested that microwave irradiation with the assistance of H2O2/TiO2 might be a potential technology for the degradation of PCB – contaminated oil. The experiments show that MW irradiation, H2O2 oxidant and TiO2 catalyst lead to a degradation efficiency of PCBs only in the presence of ethanol. The results showed that the addition of ethanol significantly enhanced degradation efficiency of PCBs.

  18. Measurement and correlation of solubility of xylitol in binary water+ethanol solvent mixtures between 278.00 K and 323.00K

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhanzhong; Wang, Qian; Liu, Xiangshan; Fang, Wenzhi; Li, Yan; Xiao, Huazhi [Tianjin University, Tianjin (China)

    2013-04-15

    The solubility of xylitol in ethanol+water solvent mixtures was measured at temperatures ranging from 278.00 K to 323.00 K at atmospheric pressure by using a laser technique. The results of these measurements were correlated by the combined nearly ideal binary solvent CNIBS/Redlich-Kister equation. The experimental solubility and correlation equation in this work can be used as essential data and models in the purification process of xylitol. The variant 2 in the CNIBS/R-K models was confirmed to be more adaptable to predict solubility of xylitol in binary ethanol+water system. Using the experimentally measured solubilities, the thermodynamic properties of dissolution of xylitol, such as Gibbs energy, molar enthalpy of dissolution, and molar entropy of dissolution, were calculated.

  19. A Comparison of Survey Measures and Biomarkers of Secondhand Tobacco Smoke Exposure among Nonsmokers.

    Science.gov (United States)

    Okoli, Chizimuzo

    2016-01-01

    Secondhand tobacco smoke (SHS) exposure causes several adverse physical health outcomes. Conceptual differences in survey measures of 'psychosocial' (SHS exposure from smokers in an individual's life) and 'physical' (environments where an individual is exposed to SHS) SHS exposure exist. Few studies have examined the association between psychosocial and physical SHS exposures measures in comparison to biomarkers of SHS exposure. A secondary analysis of cross-sectional data was examined among a convenience sample of 20 adults. Data included survey items on SHS exposure and hair nicotine and saliva cotinine levels. Spearman analysis was used to assess correlations among variables. Medium and strong correlations were found among SHS exposure measures with the exception of saliva cotinine levels. Strong correlations were found among and between psychosocial and physical SHS exposure measures. Hair nicotine levels had medium strength associations with only perceived frequency of SHS exposure. As psychosocial measures of exposure were associated with biomarkers, such measures (particularly perceived frequency of SHS exposure) should be added to surveys in addition to physical SHS exposure measures to enhance accuracy of SHS measurement. Future explorations with robust sample sizes should further examine the strength of relationship between psychosocial and physical SHS exposure measures. © 2015 Wiley Periodicals, Inc.

  20. The Nature Contact Questionnaire: a measure of healthy workplace exposure.

    Science.gov (United States)

    Largo-Wight, Erin; Chen, W William; Dodd, Virginia; Weiler, Robert

    2011-01-01

    Understanding and promoting healthy workplaces is an important and growing area of interest in occupational health. Nature contact is a central component to the study of and promotion of healthy places. Previous findings suggest that nature contact influences health via stress appraisal process. Currently, there are no known comprehensive valid and reliable measures of nature contact, which presents obstacles to research and worksite health promotion. This study was designed to develop and test an instrument to measure nature contact at work, entitled the Nature Contact Questionnaire (NCQ), 16-item self-reported checklist to measure actual exposure. A sample of 503 (30% response rate) office staff completed the questionnaire. Office staff were sent an email with a link to the electronic survey twice, two weeks apart. Content and construct validity (KMO=0.68), internal consistency (Alpha=0.64), and test-retest reliability (r=0.85, pnature contact, which allows research to compare forms of nature contact to best inform practice and design of healthy places.

  1. Ultraviolet Exposure, Measurement and Protection in Townsville, Australia

    International Nuclear Information System (INIS)

    Moise, A.F.

    2000-01-01

    This presentation summarises some of the main results from three different studies conducted in Townsville, Australia, investigating recent topics in personal exposure to solar UV radiation: exposure during early childhood, exposure during school hours, and the UV protection of various shade structures. (author)

  2. Measuring CO 2 and N 2 O Mass Transfer into GAP-1 CO 2 –Capture Solvents at Varied Water Loadings

    Energy Technology Data Exchange (ETDEWEB)

    Whyatt, Greg A.; Zwoster, Andy; Zheng, Feng; Perry, Robert J.; Wood, Benjamin R.; Spiry, Irina; Freeman, Charles J.; Heldebrant, David J.

    2017-04-12

    This paper investigates the CO2 and N2 O absorption behavior in the water-lean gamma amino propyl (GAP)-1/TEG solvent system using a wetted-wall contactor. Testing was performed on a blend of GAP-1 aminosilicone in triethylene glycol at varied water loadings in the solvent. Measurements were made with CO2 and N2 O at representative lean (0.04 mol CO2/mol alkalinity), middle (0.13 mol CO2 /mol alkalinity) and rich (0.46 mol CO2 /mol alkalinity) solvent loadings at 0, 5, 10 and 15 wt% water loadings at 40, 60 and 80C° and N2 O at (0.08-0.09 mol CO2 /mol alkalinity) at 5 wt% water at 40, 60 and 80C°. CO2 flux was found to be non-linear with respect to log mean pressure driving force (LMPD). Liquid-film mass transfer coefficients (k'g) were calculated by subtracting the gas film resistance (determined from a correlation from literature) from the overall mass transfer measurement. The resulting k'g values for CO2 and N2 O in GAP-1/TEG mixtures were found to be higher than that of 5M aqueous monoethanolamine under comparable driving force albeit at higher solvent viscosities. The k'g values for CO2 were also found to decrease with increasing solvent water content and increase with a decrease in temperature. These observations indicate that mass transfer of CO2 in GAP-1/TEG is linked to the physical solubility of CO2 , which is higher in organic solvents compared to water. This paper expands on the understanding of the unique mass transfer behavior and kinetics of CO2 capture in water-lean solvents.

  3. Exposure Research Going Mobile: A Smartphone-Based Measurement of Media Exposure to Political Information in a Convergent Media Environment

    DEFF Research Database (Denmark)

    Ohme, J.; Albaek, E.; H. de Vreese, C.

    2016-01-01

    platform modes. The study furthermore confirms limitations of mere usage time measurements of social media platforms in effects research and explores a range of actual content types that citizens encounter in social networks. It recommends more frequent use of mobile exposure measurements and argues...... for a content-related assessment of social media use in effects research. © 2016 Taylor & Francis.......In today’s convergent media environment, media exposure becomes increasingly channel-independent and social media-bound, and media content is more frequently accessed on mobile devices. This calls for new approaches to measuring media exposure. This study applies an innovative approach to survey (n...

  4. Exposure research going mobile: A smartphone-based measurement of media exposure to political information in a convergent media environment

    NARCIS (Netherlands)

    Ohme, J.; Albæk, E.; de Vreese, C.H.

    2016-01-01

    In today’s convergent media environment, media exposure becomes increasingly channel-independent and social media-bound, and media content is more frequently accessed on mobile devices. This calls for new approaches to measuring media exposure. This study applies an innovative approach to survey (n

  5. Radiation exposure in nuclear medicine: real-time measurement

    Directory of Open Access Journals (Sweden)

    Iara Sylvain

    2002-09-01

    Full Text Available French regulations have introduced the use of electronic dosimeters for personal monitoring of workers. In order to evaluate the exposure from diagnostic procedures to nuclear medicine staff, individual whole-body doses were measured daily with electronic (digital personal dosimeters during 20 consecutive weeks and correlated with the work load of each day. Personal doses remained always below 20 µSv/d under normal working conditions. Radiation exposure levels were highest to tech staff, nurses and stretcher-bearers. The extrapolated annual cumulative doses for all staff remained less than 10 % of the maximum legal limit for exposed workers (2 mSv/yr. Electronic dosimeters are not technically justified for routine survey of staff. The high sensitivity and immediate reading of electronic semiconductor dosimeters may become very useful for exposure control under risky working conditions. It may become an important help for optimising radiation protection.A legislação francesa introduziu o uso de dosímetros eletrônicos para monitoração da exposição do trabalhador. Afim de avaliar a exposição do trabalhador proveniente de exames diagnósticos em medicina nuclear, doses individuais do corpo inteiro foram medidas diariamente com dosímetros eletrônicos (digitais durante 20 semanas consecutivas e correlatas com as atividades de trabalho de cada dia. As doses foram sempre inferiores à 20 µSv por dia em condições normais de trabalho. Os níveis de exposição de radiação mais elevados foram para os enfermeiros, manipuladores e maqueiros. A extrapolação da dose anual para todos os trabalhadores foi menos que 10 % do limite máximo legal para os trabalhadores expostos (2 mSv/ano. Dosímetros eletrônicos não são tecnicamente justificados para a o controle de rotina da exposição dos trabalhadores, mas a alta sensibilidade e a leitura imediata desses dosímetros podem vir a serem muito úteis para o controle da exposição em condi

  6. LIMITATIONS ON THE USES OF MULTIMEDIA EXPOSURE MEASUREMENTS FOR MULTIPATHWAY EXPOSURE ASSESSMENT - PART II: EFFECTS OF MISSING DATA AND IMPRECISION

    Science.gov (United States)

    Multimedia data from two probability-based exposure studies were investigated in terms of how missing data and measurement-error imprecision affected estimation of population parameters and associations. Missing data resulted mainly from individuals' refusing to participate in c...

  7. Exposure of Finnish population to ultraviolet radiation and radiation measurements

    International Nuclear Information System (INIS)

    Hoikkala, M.; Lappalainen, J.; Leszczynski, K.; Paile, W.

    1990-01-01

    This report is based on a survey of the literature on radiation risks involved in sunbathing and the use of solaria. The purpose of the report is to provide background information for the development of regulations on solaria and for informing the public about the risks posed by solaria and the sun. The report gives an overview of the properties and biological effects of ultraviolet radiation. The most important regulations and recommendations issued in various countries are presented. The connection between ultraviolet radiation and the risks of skin cancer is examined both on a general level and in reference to information obtained from the Finnish Cancer Registry. In Finland, the incidence of melanomas nearly tripled between 1960 and 1980. The most important cause is considered to be the population's increased exposure to the su's ultraviolet radiation. There are no reliable data on the connection between the use of solaria and the risks of skin cancer. It is estimated, however, that solaria account for less than 10 per cent of the skin cancer risk of the whole population. There are some difficult physical problems associated with the measurement of ultraviolet radiation emitted by both natural sources and solaria. A preliminary study of these problems has been undertaken by means of a survey of the available literature, supplemented by a review of measurements performed by the Finnish Centre For Radiation and Nuclear Safety. The estimated inaccuracy of the Optronic 742 spectroradiometer used by the Centre in the measurement of ultraviolet radiation emitted by the sun and solaria is about +-14%

  8. Negative control exposure studies in the presence of measurement error: implications for attempted effect estimate calibration.

    Science.gov (United States)

    Sanderson, Eleanor; Macdonald-Wallis, Corrie; Davey Smith, George

    2018-04-01

    Negative control exposure studies are increasingly being used in epidemiological studies to strengthen causal inference regarding an exposure-outcome association when unobserved confounding is thought to be present. Negative control exposure studies contrast the magnitude of association of the negative control, which has no causal effect on the outcome but is associated with the unmeasured confounders in the same way as the exposure, with the magnitude of the association of the exposure with the outcome. A markedly larger effect of the exposure on the outcome than the negative control on the outcome strengthens inference that the exposure has a causal effect on the outcome. We investigate the effect of measurement error in the exposure and negative control variables on the results obtained from a negative control exposure study. We do this in models with continuous and binary exposure and negative control variables using analysis of the bias of the estimated coefficients and Monte Carlo simulations. Our results show that measurement error in either the exposure or negative control variables can bias the estimated results from the negative control exposure study. Measurement error is common in the variables used in epidemiological studies; these results show that negative control exposure studies cannot be used to precisely determine the size of the effect of the exposure variable, or adequately adjust for unobserved confounding; however, they can be used as part of a body of evidence to aid inference as to whether a causal effect of the exposure on the outcome is present.

  9. 15NH/D-SOLEXSY experiment for accurate measurement of amide solvent exchange rates: application to denatured drkN SH3

    International Nuclear Information System (INIS)

    Chevelkov, Veniamin; Xue, Yi; Krishna Rao, D.; Forman-Kay, Julie D.; Skrynnikov, Nikolai R.

    2010-01-01

    Amide solvent exchange rates are regarded as a valuable source of information on structure/dynamics of unfolded (disordered) proteins. Proton-based saturation transfer experiments, normally used to measure solvent exchange, are known to meet some serious difficulties. The problems mainly arise from the need to (1) manipulate water magnetization and (2) discriminate between multiple magnetization transfer pathways that occur within the proton pool. Some of these issues are specific to unfolded proteins. For example, the compensation scheme used to cancel the Overhauser effect in the popular CLEANEX experiment is not designed for use with unfolded proteins. In this report we describe an alternative experimental strategy, where amide 15 N is used as a probe of solvent exchange. The experiment is performed in 50% H 2 O-50% D 2 O solvent and is based on the (HACACO)NH pulse sequence. The resulting spectral map is fully equivalent to the conventional HSQC. To fulfill its purpose, the experiment monitors the conversion of deuterated species, 15 N D , into protonated species, 15 N H , as effected by the solvent exchange. Conceptually, this experiment is similar to EXSY which prompted the name of 15 N H/D -SOLEXSY (SOLvent EXchange SpectroscopY). Of note, our experimental scheme, which relies on nitrogen rather than proton to monitor solvent exchange, is free of the complications described above. The developed pulse sequence was used to measure solvent exchange rates in the chemically denatured state of the drkN SH3 domain. The results were found to correlate well with the CLEANEX-PM data, r = 0.97, thus providing a measure of validation for both techniques. When the experimentally measured exchange rates are converted into protection factors, most of the values fall in the range 0.5-2, consistent with random-coil behavior. However, elevated values, ca. 5, are obtained for residues R38 and A39, as well as the side-chain indole of W36. This is surprising, given that high

  10. Influence of solvent and salt concentration on the alignment properties of acrylamide copolymer gels for the measurement of RDC.

    Science.gov (United States)

    Trigo-Mouriño, Pablo; Navarro-Vázquez, Armando; Sánchez-Pedregal, Víctor M

    2012-12-01

    The dependence of molecular alignment with solvent nature and salt concentration has been investigated for mechanically stretched polyacrylamide copolymer gels. Residual dipolar couplings (RDCs) were recorded for D(2)O, DMSO-d(6), and DMSO-d(6)/D(2)O solutions containing different proportions of the solvents and different sodium chloride concentrations. Alignment tensors were determined by fitting the experimental RDCs to the DFT-computed structure of N-methylcodeinium ion. Analysis of the tensors shows that the degree of alignment decreases with the proportion of DMSO-d(6) as well as with the concentration of sodium chloride, most likely due to enhanced ion-pair aggregation. Furthermore, rotation of the alignment tensor is observed when increasing the salt concentration. Copyright © 2012 John Wiley & Sons, Ltd.

  11. 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

  12. Sample loading for C-14 measurement in the simulated organic solvent waste from a CANDU Nuclear Power Plant

    International Nuclear Information System (INIS)

    Dianu, Magdalena; Podina, C.; Nita, Valentina

    2005-01-01

    Full text: Sample preparation is a critical step in obtaining accurate results in scintillation counting. Standard (22 ml) glass and plastic vials were used in these experiments. The preliminary research was conducted using glass vials to allow visual verification that a homogeneous solution is obtained at the desired cocktail/sample ratio. Then, the research was moved into plastic vials to reduce backgrounds and improve the counting rate. Samples were counted in a Model 2100 TR Packard TRI-CARB liquid scintillation analyzer. The paper mainly contains: - Composition and data about liquid scintillation cocktails used (tables); - Characterization of radioactive waste - organic solvent contaminated with C-14; - Sample loading (tables); - Efficiency vs Sample Loading - for each cocktail used. Organic solvent sample volumes were added to the vials in 0.5 ml increments from 1 ml to 2 ml. Then, the liquid scintillation cocktail was added so that the sample-cocktail volume was 20 ml. Each vial was shaken vigorously for several seconds after each addition to ensure homogeneity and count. Blank vials were prepared using C-14-free organic solvent samples in the same sample-cocktail proportions. After at least two hours, the samples and blank vials were counted for ten minutes, using a Packard counter. (authors)

  13. Children's exposure assessment of radiofrequency fields: Comparison between spot and personal measurements.

    Science.gov (United States)

    Gallastegi, Mara; Huss, Anke; Santa-Marina, Loreto; Aurrekoetxea, Juan J; Guxens, Mònica; Birks, Laura Ellen; Ibarluzea, Jesús; Guerra, David; Röösli, Martin; Jiménez-Zabala, Ana

    2018-05-24

    Radiofrequency (RF) fields are widely used and, while it is still unknown whether children are more vulnerable to this type of exposure, it is essential to explore their level of exposure in order to conduct adequate epidemiological studies. Personal measurements provide individualized information, but they are costly in terms of time and resources, especially in large epidemiological studies. Other approaches, such as estimation of time-weighted averages (TWAs) based on spot measurements could simplify the work. The aims of this study were to assess RF exposure in the Spanish INMA birth cohort by spot measurements and by personal measurements in the settings where children tend to spend most of their time, i.e., homes, schools and parks; to identify the settings and sources that contribute most to that exposure; and to explore if exposure assessment based on spot measurements is a valid proxy for personal exposure. When children were 8 years old, spot measurements were conducted in the principal settings of 104 participants: homes (104), schools and their playgrounds (26) and parks (79). At the same time, personal measurements were taken for a subsample of 50 children during 3 days. Exposure assessment based on personal and on spot measurements were compared both in terms of mean exposures and in exposure-dependent categories by means of Bland-Altman plots, Cohen's kappa and McNemar test. Median exposure levels ranged from 29.73 (in children's bedrooms) to 200.10 μW/m 2 (in school playgrounds) for spot measurements and were higher outdoors than indoors. Median personal exposure was 52.13 μW/m 2 and median levels of assessments based on spot measurements ranged from 25.46 to 123.21 μW/m 2 . Based on spot measurements, the sources that contributed most to the exposure were FM radio, mobile phone downlink and Digital Video Broadcasting-Terrestrial, while indoor and personal sources contributed very little (altogether spot measurements, with the latter

  14. How to statistically analyze nano exposure measurement results: Using an ARIMA time series approach

    NARCIS (Netherlands)

    Klein Entink, R.H.; Fransman, W.; Brouwer, D.H.

    2011-01-01

    Measurement strategies for exposure to nano-sized particles differ from traditional integrated sampling methods for exposure assessment by the use of real-time instruments. The resulting measurement series is a time series, where typically the sequential measurements are not independent from each

  15. An evaluation of four measures of adolescents' exposure to cigarette marketing in stores.

    Science.gov (United States)

    Feighery, Ellen C; Henriksen, Lisa; Wang, Yun; Schleicher, Nina C; Fortmann, Stephen P

    2006-12-01

    This study evaluates four measures of exposure to retail cigarette marketing in relation to adolescent smoking behavior. The measures are (a) shopping frequency in types of stores known to carry more cigarette advertising than other store types, (b) shopping frequency in specific stores that sell cigarettes in the study community, (c) the amount of exposure to cigarette brand impressions in stores where students shopped, and (d) perceived exposure to cigarette advertising. The study combined data from classroom surveys administered to 6th-, 7th-, and 8th-grade students in three California middle schools, and direct store observations quantifying cigarette marketing materials and product placement in stores where students shopped. Logistic regression models were used to examine how each exposure measure related to the odds of ever smoking and susceptibility to smoke, controlling for grade, gender, ethnicity, school performance, unsupervised time, and exposure to household and friend smoking. Frequent exposure to retail cigarette marketing as defined by each of the four measures was independently associated with a significant increase in the odds of ever smoking. All but the measure of exposure to store types was associated with a significant increase in the odds of susceptibility to smoke. Four measures of exposure to retail cigarette marketing may serve equally well to predict adolescent smoking but may vary in cost, complexity, and meaning. Depending on the outcomes of interest, the most useful measure may be a combination of self-reported exposure to types of stores that contain cigarette marketing and perceived exposure to such messages.

  16. Influence of evaporation and solvent mixtures on the absorption of toluene and n-butanol in human skin in vitro.

    Science.gov (United States)

    Boman, A; Maibach, H I

    2000-03-01

    The influence of forced ventilation on the percutaneous absorption of butanol and toluene was studied in vitro. Human skin was exposed to the neat solvents and the solvents in binary mixtures with each other and in ternary mixtures with chloroform:methanol. The exposure was either unventilated or ventilated with various flow rates. At the ventilated exposure the skin absorption of all solvents and solvent mixtures was markedly reduced compared to unventilated exposure. Exposure with solvent mixtures increased the amounts of solvent absorbed as well as absorption rates. The absorption of the butanol component was most influenced. Increase in absorption was 11 to 9 times depending on whether toluene or chloroform/methanol was cosolvent. There was also an interindividual variation of absorption rate, varying with a factor of 3.5 for toluene and 4.3 for n-butanol within the 3 skin donors used. Skin absorption of volatile organic solvents at continuous ventilated conditions is related to their volatility and to the ventilation rate.A sufficient workplace ventilation is an important occupational hygienic measure not only to reduce exposure via respiration but to reduce absorption via the skin of volatile compounds as well.

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

    International Nuclear Information System (INIS)

    Mauro, F.; Lovisolo, G.A.; Raganella, L.

    1992-01-01

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

  18. Impaired colour vision in workers exposed to organic solvents: A systematic review.

    Science.gov (United States)

    Betancur-Sánchez, A M; Vásquez-Trespalacios, E M; Sardi-Correa, C

    2017-01-01

    To evaluate recent evidence concerning the relationship between the exposure to organic solvents and the impairment of colour vision. A bibliographic search was conducted for scientific papers published in the last 15 years, in the LILACS, PubMed, Science Direct, EBSCO, and Cochrane databases that included observational studies assessing the relationship between impairment in colour vision and exposure to organic solvents. Eleven studies were selected that were performed on an economically active population and used the Lanthony D-15 desaturated test (D-15d), measured the exposure to organic solvents, and included unexposed controls. It was found that there is a statistically significant relationship between the exposure to organic solvents and the presence of an impairment in colour vision. The results support the hypothesis that exposure to organic solvents could induce acquired dyschromatopsia. The evaluation of colour vision with the D-15d test is simple and sensitive for diagnosis. More studies need to be conducted on this subject in order to better understand the relationship between impaired colour vision and more severe side effects caused by this exposure. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Equilibrium disorders in workers exposed to mixed solvents.

    Science.gov (United States)

    Giorgianni, Concetto; Tanzariello, Mariagiuseppina; De Pasquale, Domenico; Brecciaroli, Renato; Spatari, Giovanna

    2018-02-06

    Organic solvents cause diseases of the vestibular system. However, little is known regarding the correlation between vestibular damage and exposure to organic solvents below threshold limit values. The best measure by which to evaluate vestibular disorders is static and dynamic posturography. The aim of this study was to evaluate equilibrium disorders via static and dynamic posturography in workers without clear symptoms and exposed to low doses of mixed solvents. 200 subjects were selected. Using an Otometrics device (Madsen, Denmark), all subjects endured static and dynamic posturography testing with both eyes-open and eyes-closed conditions. Results were compared with a control group of unexposed individuals. Based on the obtained data, the following results can be drawn: (a) subjects exposed to mixtures of solvents show highly significant differences regarding all static and dynamic posturography parameters in comparison to the control group; (b) posturography testing has proven to be a valid means by which to detect subliminal equilibrium disorders in subjects exposed to solvents. We can confirm that refinery workers exposed to mixtures of solvents can present subliminal equilibrium disorders. Early diagnosis of the latter is made possible by static and dynamic posturography.

  20. Multiple sclerosis and organic solvents

    DEFF Research Database (Denmark)

    Mortensen, J T; Brønnum-Hansen, Henrik; Rasmussen, K

    1998-01-01

    We investigated a possible causal relation between exposure to organic solvents in Danish workers (housepainters, typographers/printers, carpenters/cabinetmakers) and onset of multiple sclerosis. Data on men included in the Danish Multiple Sclerosis Register (3,241 men) were linked with data from......, and butchers. Over a follow-up period of 20 years, we observed no increase in the incidence of multiple sclerosis among men presumed to be exposed to organic solvents. It was not possible to obtain data on potential confounders, and the study design has some potential for selection bias. Nevertheless......, the study does not support existing hypotheses regarding an association between occupational exposure to organic solvents and multiple sclerosis....

  1. Neurologic effects of solvents in older adults. (UW retired worker study). Final performance report

    Energy Technology Data Exchange (ETDEWEB)

    Daniell, W.E.

    1993-11-12

    The possibility that previous occupational exposure to solvents might be associated with clinically significant neurological dysfunction in older adults was investigated in a cross-sectional study. Subjects included 67 painters, 22 aerospace painters and fuel cell sealers, and a comparison group of 126 carpenters. All subjects had retired from regular employment at least 1 year prior to the study. As measured by semiquantitative exposure index, the cumulative histories of lifetime occupational solvent exposure were on the average comparable in the two exposed study groups, painters and aerospace workers. The carpenters differed from the other groups in solvent exposure by several orders of magnitude. The painters had a significantly higher history of consuming alcoholic beverages than did the other two study groups. The painters had a significantly higher score on the Beck Depression Inventory, a measure of current depressive symptoms. The painters reported significantly more general neurologic symptoms than did the other two groups. The aerospace workers showed much greater evidence of possible adverse effects from former solvent exposure on current neuropsychological function than did the painters when determined by reasoning and memory tests, memory visual motor speed and motor tests. No evidence of persistent effects on liver or renal excretory function was seen in solvent exposed subjects.

  2. Consequences of exposure measurement error for confounder identification in environmental epidemiology

    DEFF Research Database (Denmark)

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

    2003-01-01

    Non-differential measurement error in the exposure variable is known to attenuate the dose-response relationship. The amount of attenuation introduced in a given situation is not only a function of the precision of the exposure measurement but also depends on the conditional variance of the true...... exposure given the other independent variables. In addition, confounder effects may also be affected by the exposure measurement error. These difficulties in statistical model development are illustrated by examples from a epidemiological study performed in the Faroe Islands to investigate the adverse...

  3. Occupational exposure to chrome VI compounds in French companies: results of a national campaign to measure exposure (2010-2013).

    Science.gov (United States)

    Vincent, Raymond; Gillet, Martine; Goutet, Pierre; Guichard, Christine; Hédouin-Langlet, Catherine; Frocaut, Anne Marie; Lambert, Pierre; Leray, Fabrice; Mardelle, Patricia; Dorotte, Michel; Rousset, Davy

    2015-01-01

    A campaign to measure exposure to hexavalent chromium compounds was carried out in France by the seven CARSAT chemistry laboratories, CRAMIF laboratory, and INRS over the 2010-2013 period. The survey included 99 companies involved in various activity sectors. The inhalable fraction of airborne particles was sampled, and exposure levels were determined using ion chromatography analysis combined with post-column derivatization and UV detection. The quality of the measurement results was guaranteed by an inter-laboratory comparison system involving all the laboratories participating in this study. Exposure levels frequently exceeded the French occupational exposure limit value (OELV) of 1 µg m(-3), in activities such as thermal metallization and manufacturing and application of paint in the aeronautics sector. The results also reveal a general trend for a greater proportion of soluble Chromium VI (Cr VI) compounds compared with insoluble compounds. Qualitative and quantitative information relating to the presence of other metallic compounds in the air of workplaces is also provided, for example for Cr III, Ni, Fe, etc. The sampling strategy used and the measurement method are easy to implement, making it possible to check occupational exposure with a view to comparing it to an 8 h-OELV of 1 µg m(-3). © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  4. Exposure estimates based on broadband elf magnetic field measurements versus the ICNIRP multiple frequency rule

    International Nuclear Information System (INIS)

    Paniagua, Jesus M.; Rufo, Montana; Jimenez, Antonio; Pachon, Fernando T.; Carrero, Julian

    2015-01-01

    The evaluation of exposure to extremely low-frequency (ELF) magnetic fields using broadband measurement techniques gives satisfactory results when the field has essentially a single frequency. Nevertheless, magnetic fields are in most cases distorted by harmonic components. This work analyses the harmonic components of the ELF magnetic field in an outdoor urban context and compares the evaluation of the exposure based on broadband measurements with that based on spectral analysis. The multiple frequency rule of the International Commission on Non-ionizing Radiation Protection (ICNIRP) regulatory guidelines was applied. With the 1998 ICNIRP guideline, harmonics dominated the exposure with a 55 % contribution. With the 2010 ICNIRP guideline, however, the primary frequency dominated the exposure with a 78 % contribution. Values of the exposure based on spectral analysis were significantly higher than those based on broadband measurements. Hence, it is clearly necessary to determine the harmonic components of the ELF magnetic field to assess exposure in urban contexts. (authors)

  5. Estimation methods with ordered exposure subject to measurement error and missingness in semi-ecological design

    Directory of Open Access Journals (Sweden)

    Kim Hyang-Mi

    2012-09-01

    Full Text Available Abstract Background In epidemiological studies, it is often not possible to measure accurately exposures of participants even if their response variable can be measured without error. When there are several groups of subjects, occupational epidemiologists employ group-based strategy (GBS for exposure assessment to reduce bias due to measurement errors: individuals of a group/job within study sample are assigned commonly to the sample mean of exposure measurements from their group in evaluating the effect of exposure on the response. Therefore, exposure is estimated on an ecological level while health outcomes are ascertained for each subject. Such study design leads to negligible bias in risk estimates when group means are estimated from ‘large’ samples. However, in many cases, only a small number of observations are available to estimate the group means, and this causes bias in the observed exposure-disease association. Also, the analysis in a semi-ecological design may involve exposure data with the majority missing and the rest observed with measurement errors and complete response data collected with ascertainment. Methods In workplaces groups/jobs are naturally ordered and this could be incorporated in estimation procedure by constrained estimation methods together with the expectation and maximization (EM algorithms for regression models having measurement error and missing values. Four methods were compared by a simulation study: naive complete-case analysis, GBS, the constrained GBS (CGBS, and the constrained expectation and maximization (CEM. We illustrated the methods in the analysis of decline in lung function due to exposures to carbon black. Results Naive and GBS approaches were shown to be inadequate when the number of exposure measurements is too small to accurately estimate group means. The CEM method appears to be best among them when within each exposure group at least a ’moderate’ number of individuals have their

  6. Measurement and correlation of solubility of trans-resveratrol in 11 solvents at T = (278.2, 288.2, 298.2, 308.2, and 318.2) K

    Energy Technology Data Exchange (ETDEWEB)

    Sun Xilan; Peng Bin [Department of Chemistry, Zhejiang University, Hangzhou 310027 (China); Yan Weidong [Department of Chemistry, Zhejiang University, Hangzhou 310027 (China)], E-mail: yanweidong@zju.edu.cn

    2008-04-15

    The solubilities of trans-resveratrol in methanol, ethanol, 1-propanol, 2- propanol, 1-butanol, 1-pentanol, 1-hexanol, ethyl acetate, tetrahydrofuran, acetone, and water (pH 6.0) solvents were measured at T = (278.2, 288.2, 298.2, 308.2, and 318.2) K. The solubilities of trans-resveratrol in selected solvents increase with temperature, but decrease with increasing the number of carbon in alcohol solvents. The experimental data were correlated using a thermodynamic equation.

  7. Measurement and correlation of solubility of trans-resveratrol in 11 solvents at T = (278.2, 288.2, 298.2, 308.2, and 318.2) K

    International Nuclear Information System (INIS)

    Sun Xilan; Peng Bin; Yan Weidong

    2008-01-01

    The solubilities of trans-resveratrol in methanol, ethanol, 1-propanol, 2- propanol, 1-butanol, 1-pentanol, 1-hexanol, ethyl acetate, tetrahydrofuran, acetone, and water (pH 6.0) solvents were measured at T = (278.2, 288.2, 298.2, 308.2, and 318.2) K. The solubilities of trans-resveratrol in selected solvents increase with temperature, but decrease with increasing the number of carbon in alcohol solvents. The experimental data were correlated using a thermodynamic equation

  8. The use of deuterated ethyl acetate in highly concentrated electrolyte as a low-cost solvent for in situ neutron diffraction measurements of Li-ion battery electrodes

    International Nuclear Information System (INIS)

    Petibon, R.; Li, Jing; Sharma, Neeraj; Pang, Wei Kong; Peterson, Vanessa K.; Dahn, J.R.

    2015-01-01

    A low-cost deuterated electrolyte suitable for in situ neutron diffraction measurements of normal and high voltage Li-ion battery electrodes is reported here. Li[Ni 0.4 Mn 0.4 Co 0.2 ]O 2 /graphite (NMC(442)/graphite) pouch cells filled with 1:0.1:2 (molar ratio) of lithium bis(fluorosulfonyl) imide (LiFSi):LiPF 6 : ethyl acetate (EA) and LiFSi:LiPF 6 :deuterated EA (d8-EA) electrolytes were successfully cycled between 2.8 V and 4.7 V at 40°C for 250 h without significant capacity loss, polarization growth, or gas production. The signal-to-noise ratio of neutron powder diffraction patterns taken on NMC(442) powder with a conventional deuterated organic carbonate-based electrolyte and filled with LiFSi:LiPF 6 :d8-EA electrolyte were virtually identical. Out of all the solvents widely available in deuterated form tested in highly-concentrated systems, EA was the only one providing a good balance between cost and charge-discharge capacity retention to 4.7 V. The use of such an electrolyte blend would half the cost of deuterated solvents needed for in situ neutron diffraction measurements of Li-ion batteries compared to conventional deuterated carbonate-based electrolytes

  9. For good measure: Origins and prospects of exposure science (2007 Wesolowski Award Lecture).

    Science.gov (United States)

    Fenske, Richard A

    2010-09-01

    Measurement is the foundation of exposure science. Associations between illness and environmental agents have been observed for millennia, but the ability to quantify exposure and dose has been possible only in the last century. Improved means of measurement and refined concepts of who, what, when, where, and why to measure have been the seminal contributions of exposure science to the study of disease causation and prevention. This paper examines critical advancements in exposure assessment associated with workplace health and safety, and the groundbreaking work of the US Public Health Service. Many of the key concepts of modern exposure science have their origin in these early studies. Occupational hygiene scientists have conducted receptor-based exposure analyses for more than 80 years, evaluating indoor air, defining microenvironments, and developing personal sampling techniques. Biological monitoring of community populations including children, dermal exposure monitoring, duplicate diet studies, and multi-pathway, aggregate exposure assessments can be traced to early public health studies. As we look to the future, we see that new technologies and techniques are expanding the scope of exposure science dramatically. We need to ensure that the highest of scientific standards are maintained, make a greater effort to include occupational hygiene scientists, microbiologists, and behavioral scientists in the field, and promote new sources of training and research support. Exposure science has a critical role to play in the prevention strategy that is central to public health.

  10. Measurement of personal exposure to volatile organic compounds and particle associated PAH in three UK regions.

    Science.gov (United States)

    Saborit, Juana Mari Delgado; Aquilina, Noel J; Meddings, Claire; Baker, Stephen; Vardoulakis, Sotiris; Harrison, Roy M

    2009-06-15

    Personal exposures to 15 volatile organic compounds (VOC) and 16 polycyclic aromatic hydrocarbons (PAH) of 100 adult nonsmokers living in three UK areas, namely London, West Midlands, and rural South Wales, were measured using an actively pumped sampler carried around by the volunteers for 5/1 (VOC/PAH) consecutive 24-h periods, following their normal lifestyle. Results from personal exposure measurements categorized by geographical location, type of dwelling, and exposure to environmental tobacco smoke (ETS) are presented. The average personal exposure concentration to benzene, 1,3-butadiene, and benzo(a)pyrene representing the main carcinogenic components of the VOC and PAH mixture were 2.2 +/- 2.5 microg/m3, 0.4 +/- 0.7 microg/m3, and 0.3 +/- 0.7 ng/m3 respectively. The association of a number of generic factors with personal exposure concentrations was investigated, including first-line property, traffic, the presence of an integral garage, and ETS. Only living in houses with integral garages and being exposed to ETS were identified as unequivocal contributors to VOC personal exposure, while only ETS had a clear effect upon PAH personal exposures. The measurements of personal exposures were compared with health-based European and UK air quality guidelines, with some exceedences occurring. Activities contributing to high personal exposures included the use of a fireplace in the home, ETS exposure, DIY (i.e., construction and craftwork activities), and photocopying, among others.

  11. Measure of enzymatic activity coincident with 2450 MHz microwave exposure

    Energy Technology Data Exchange (ETDEWEB)

    Ward, T R; Allis, J W; Elder, J A

    1975-09-01

    Enzyme preparations were exposed to microwave radiation at 2450 MHz and enzymatic activity was simultaneously monitored spectrophotometrically with a crossed-beam exposure detection system. Enzymes studied were glucose 6-phosphate dehydrogenase from human red blood cells and yeast, adenylate kinase from rat liver mitochondria and rabbit muscle, and rat liver microsomal NADPH cytochrome c reductase. No difference was found between the specific activity at 25/sup 0/C of unirradiated controls and enzyme preparations irradiated at an absorbed dose rate of 42 W/kg.

  12. [Multiple mere exposure effect: category evaluation measured in the Go/No-go association task (GNAT)].

    Science.gov (United States)

    Kawakami, Naoaki; Yoshida, Fujio

    2011-12-01

    The effect on likability of multiple subliminal exposures to the same person was investigated. Past studies on the mere exposure effect indicated a correlation between the frequency of repeated exposure to the same stimulus and likability. We proposed that exposure to various stimuli of the same person would have a stronger effect on likability. Participants were subliminally exposed to photographs of a person's face taken from seven angles (multi-angle-exposure) three times each (Experiment 1), or photographs of a person with seven facial expressions (multi-expression-exposure) three times each (Experiment 2). Then, the likability toward the exposed person was measured using the Go/No-go Association Task. The results indicated that the effect of the multiple exposures from various angles was equivalent to exposure to only one full-face photograph shown 21 times (Experiment 1). Moreover, likability was significantly higher in the case of exposure to various facial expressions than for exposure to only a single facial expression (Experiment 2). The results suggest that exposure to various stimuli in a category is more effective than repeated exposure to a single stimulus for increasing likability.

  13. Measuring sun exposure in epidemiological studies: Matching the method to the research question.

    Science.gov (United States)

    King, Laura; Xiang, Fan; Swaminathan, Ashwin; Lucas, Robyn M

    2015-12-01

    Sun exposure has risks and benefits for health. Testing these associations requires tools for measuring sun exposure that are feasible and relevant to the time-course of the health outcome. Recent sun exposure, e.g. the last week, is best captured by dosimeters and sun diaries. These can also be used for medium-term sun exposure e.g. over several weeks, but incur a high participant burden. Self-reported data on "typical time outdoors" for working and non-working days, is less detailed and not influenced by day-to-day variation. Over a longer period, e.g. the lifetime, or for particular life stages, proxies of sun exposure, such as latitude of residence or ambient ultraviolet (UV) radiation levels (from satellites or ground-level monitoring) can be used, with additional detail provided by lifetime sun exposure calendars that include locations of residence, usual time outdoors, and detail of sunburn episodes. Objective measures of lifetime sun exposure include microtopography of sun-exposed skin (e.g. using silicone casts) or conjunctival UV autofluorescence. Potential modifiers of the association between sun exposure and the health outcome, such as clothing coverage and skin colour, may also need to be measured. We provide a systematic approach to selecting sun exposure measures for use in epidemiological health research. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Smoking in film in New Zealand: measuring risk exposure

    Directory of Open Access Journals (Sweden)

    Stockwell Alannah

    2006-10-01

    Full Text Available Abstract Background Smoking in film is a risk factor for smoking uptake in adolescence. This study aimed to quantify exposure to smoking in film received by New Zealand audiences, and evaluate potential interventions to reduce the quantity and impact of this exposure. Methods The ten highest-grossing films in New Zealand for 2003 were each analysed independently by two viewers for smoking, smoking references and related imagery. Potential interventions were explored by reviewing relevant New Zealand legislation, and scientific literature. Results Seven of the ten films contained at least one tobacco reference, similar to larger film samples. The majority of the 38 tobacco references involved characters smoking, most of whom were male. Smoking was associated with positive character traits, notably rebellion (which may appeal to adolescents. There appeared to be a low threshold for including smoking in film. Legislative or censorship approaches to smoking in film are currently unlikely to succeed. Anti-smoking advertising before films has promise, but experimental research is required to demonstrate cost effectiveness. Conclusion Smoking in film warrants concern from public health advocates. In New Zealand, pre-film anti-smoking advertising appears to be the most promising immediate policy response.

  15. Smoking in film in New Zealand: measuring risk exposure.

    Science.gov (United States)

    Gale, Jesse; Fry, Bridget; Smith, Tara; Okawa, Ken; Chakrabarti, Anannya; Ah-Yen, Damien; Yi, Jesse; Townsend, Simon; Carroll, Rebecca; Stockwell, Alannah; Sievwright, Andrea; Dew, Kevin; Thomson, George

    2006-10-04

    Smoking in film is a risk factor for smoking uptake in adolescence. This study aimed to quantify exposure to smoking in film received by New Zealand audiences, and evaluate potential interventions to reduce the quantity and impact of this exposure. The ten highest-grossing films in New Zealand for 2003 were each analysed independently by two viewers for smoking, smoking references and related imagery. Potential interventions were explored by reviewing relevant New Zealand legislation, and scientific literature. Seven of the ten films contained at least one tobacco reference, similar to larger film samples. The majority of the 38 tobacco references involved characters smoking, most of whom were male. Smoking was associated with positive character traits, notably rebellion (which may appeal to adolescents). There appeared to be a low threshold for including smoking in film. Legislative or censorship approaches to smoking in film are currently unlikely to succeed. Anti-smoking advertising before films has promise, but experimental research is required to demonstrate cost effectiveness. Smoking in film warrants concern from public health advocates. In New Zealand, pre-film anti-smoking advertising appears to be the most promising immediate policy response.

  16. The development of a high-throughput measurement method of octanol/water distribution coefficient based on hollow fiber membrane solvent microextraction technique.

    Science.gov (United States)

    Bao, James J; Liu, Xiaojing; Zhang, Yong; Li, Youxin

    2014-09-15

    This paper describes the development of a novel high-throughput hollow fiber membrane solvent microextraction technique for the simultaneous measurement of the octanol/water distribution coefficient (logD) for organic compounds such as drugs. The method is based on a designed system, which consists of a 96-well plate modified with 96 hollow fiber membrane tubes and a matching lid with 96 center holes and 96 side holes distributing in 96 grids. Each center hole was glued with a sealed on one end hollow fiber membrane tube, which is used to separate the aqueous phase from the octanol phase. A needle, such as microsyringe or automatic sampler, can be directly inserted into the membrane tube to deposit octanol as the accepted phase or take out the mixture of the octanol and the drug. Each side hole is filled with aqueous phase and could freely take in/out solvent as the donor phase from the outside of the hollow fiber membranes. The logD can be calculated by measuring the drug concentration in each phase after extraction equilibrium. After a comprehensive comparison, the polytetrafluoroethylene hollow fiber with the thickness of 210 μm, an extraction time of 300 min, a temperature of 25 °C and atmospheric pressure without stirring are selected for the high throughput measurement. The correlation coefficient of the linear fit of the logD values of five drugs determined by our system to reference values is 0.9954, showed a nice accurate. The -8.9% intra-day and -4.4% inter-day precision of logD for metronidazole indicates a good precision. In addition, the logD values of eight drugs were simultaneously and successfully measured, which indicated that the 96 throughput measure method of logD value was accurate, precise, reliable and useful for high throughput screening. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Measurement of Activity Coefficients of Solvents in Poly ( ethylene oxide ) Using Gas-Chromatographic Method and Correlation by Polymer-ASOG; Poriechirenokishido chu no yobai katsuryo keisu no gasukuromatogurafu ho ni yoru sokutei to Polymer-ASOG ni yoru sokan

    Energy Technology Data Exchange (ETDEWEB)

    Tochigi, K.; Kurita, S.; Ohashi, M. [Yuki Gosei Kogyo Co. LTd., (Japan); Kojima, K. [Nihon University, Tokyo (Japan). Department of Industrial Chemistry

    1997-09-01

    Infinite dilution activity coefficients (353.15-393.15 K) of six solvents (benzene, toluene, p-xylene, cyclohexane, acetone and methylethylketone) and activity coefficient at finite concentrations (353.15 K, 373.15 K) of these solvents in poly (ethylene oxide) are measured using gas-chromatographic method. The experimental data are then correlated by a polymer-ASOG model. 18 refs., 2 figs., 3 tabs.

  18. The primary exposure standard for Co-60 gamma radiation: characteristics and measurements procedures

    International Nuclear Information System (INIS)

    Laitano, R.F.; Toni, M.P.

    1983-01-01

    A description is given of a cavity ionization chamber used, as a primary exposure standard, at the Laboratorio di Metrologia delle Radiazioni Ionizzanti of the ENEA in Italy. The primary standard is designed to make absolute measurements of exposure due to the Co-60 gamma radiation. The procedures for the realizationof the exposure unit are also described. Finally results of some international comparisons are reported

  19. Measurement of Foreign Exchange Exposure on the Turkish Private Banks’ Stock Prices

    OpenAIRE

    Serpil Canbas; Murat Doganlar; Yildirim B.Onal

    2002-01-01

    All performance criteria of the banks are affected by the exchange rate fluctuations through foreign currency transactions and operations. However, exchange rate fluctuations -even without such activities can influence the banks through their affect on foreign competition, foreign loan demand and other banking conditions. Exchange rate exposure is classified as operation, transaction, and accounting exposures. Most of the studies, which measure these exposures, focused on the affect of the ex...

  20. Measurement of exposure dose rate by TLD in 60Co garden

    International Nuclear Information System (INIS)

    Fan Chengfang; Li Pinfang; Wu Maoliang; Zhao Quan

    1987-01-01

    The use of TLD method to measure exposure dose rate in 60 Co garden is described. As compared with chemical dosimetry, the relative deviation of measurement would not exceed 10%. The good repeatability has been proved by comparing the measurements of different times and distances with correction of decay law and 1/1 2 law. Besides, the distribution of exposure dose rate was influenced by scattering of the living plants

  1. Measuring Exposure to Protobacco Marketing and Media: A Field Study Using Ecological Momentary Assessment

    Science.gov (United States)

    Scharf, Deborah M.; Setodji, Claude M.; Shadel, William G.

    2012-01-01

    Introduction: The aims of this study were to validate ecological momentary assessment (EMA) as a method for measuring exposure to tobacco-related marketing and media and to use this method to provide detailed descriptive data on college students’ exposure to protobacco marketing and media. Methods: College students (n = 134; ages 18–24 years) recorded their exposures to protobacco marketing and media on handheld devices for 21 consecutive days. Participants also recalled exposures to various types of protobacco marketing and media at the end of the study period. Results: Retrospectively recalled and EMA-based estimates of protobacco marketing exposure captured different information. The correlation between retrospectively recalled and EMA-logged exposures to tobacco marketing and media was moderate (r = .37, p marketing through multiple channels in a relatively short period: Exposures (M = 8.24, SD = 7.85) occurred primarily in the afternoon (42%), on weekends (35%), and at point-of-purchase locations (68%) or in movies/TV (20%), and exposures to Marlboro, Newport, and Camel represented 56% of all exposures combined and 70% of branded exposures. Conclusions: Findings support the validity of EMA as a method for capturing detailed information about youth exposure to protobacco marketing and media that are not captured through other existing methods. Such data have the potential to highlight areas for policy change and prevention in order to reduce the impact of tobacco marketing on youth. PMID:22039076

  2. Measuring exposure to protobacco marketing and media: a field study using ecological momentary assessment.

    Science.gov (United States)

    Martino, Steven C; Scharf, Deborah M; Setodji, Claude M; Shadel, William G

    2012-04-01

    The aims of this study were to validate ecological momentary assessment (EMA) as a method for measuring exposure to tobacco-related marketing and media and to use this method to provide detailed descriptive data on college students' exposure to protobacco marketing and media. College students (n = 134; ages 18-24 years) recorded their exposures to protobacco marketing and media on handheld devices for 21 consecutive days. Participants also recalled exposures to various types of protobacco marketing and media at the end of the study period. Retrospectively recalled and EMA-based estimates of protobacco marketing exposure captured different information. The correlation between retrospectively recalled and EMA-logged exposures to tobacco marketing and media was moderate (r = .37, p marketing through multiple channels in a relatively short period: Exposures (M = 8.24, SD = 7.85) occurred primarily in the afternoon (42%), on weekends (35%), and at point-of-purchase locations (68%) or in movies/TV (20%), and exposures to Marlboro, Newport, and Camel represented 56% of all exposures combined and 70% of branded exposures. Findings support the validity of EMA as a method for capturing detailed information about youth exposure to protobacco marketing and media that are not captured through other existing methods. Such data have the potential to highlight areas for policy change and prevention in order to reduce the impact of tobacco marketing on youth.

  3. Assessment of Aircrew Radiation Exposure by further measurements and model development

    International Nuclear Information System (INIS)

    Lewis, B. J.; Desormeaux, M.; Green, A. R.; Bennett, L. G. I.; Butler, A.; McCall, M.; Saez Vergara, J. C.

    2004-01-01

    A methodology is presented for collecting and analysing exposure measurements from galactic cosmic radiation using a portable equipment suite and encapsulating these data into a semi-empirical model/Predictive Code for Aircrew Radiation Exposure (PCAIRE) for the assessment of aircrew radiation exposure on any flight over the solar cycle. The PCAIRE code has been validated against integral route dose measurements at commercial aircraft altitudes during experimental flights made by various research groups over the past 5 y with code predictions typically within ±20% of the measured data. An empirical correlation, based on ground-level neutron monitoring data, is detailed further for estimation of aircrew exposure from solar particle events. The semi-empirical models have been applied to predict the annual and career exposure of a flight crew member using actual flight roster data, accounting for contributions from galactic radiation and several solar energetic-particle events over the period 1973-2002. (authors)

  4. How to statistically analyze nano exposure measurement results: using an ARIMA time series approach

    International Nuclear Information System (INIS)

    Klein Entink, Rinke H.; Fransman, Wouter; Brouwer, Derk H.

    2011-01-01

    Measurement strategies for exposure to nano-sized particles differ from traditional integrated sampling methods for exposure assessment by the use of real-time instruments. The resulting measurement series is a time series, where typically the sequential measurements are not independent from each other but show a pattern of autocorrelation. This article addresses the statistical difficulties when analyzing real-time measurements for exposure assessment to manufactured nano objects. To account for autocorrelation patterns, Autoregressive Integrated Moving Average (ARIMA) models are proposed. A simulation study shows the pitfalls of using a standard t-test and the application of ARIMA models is illustrated with three real-data examples. Some practical suggestions for the data analysis of real-time exposure measurements conclude this article.

  5. 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...

  6. Bubble chamber film exposure for measurement by HPD

    International Nuclear Information System (INIS)

    Oxley, A.J.

    1978-03-01

    It is not easy for HPD measuring machines to detect tracks of low contrast in film from bubble chambers with bright-field illumination. Some of the basic aspects and limitations are considered in this paper. (author)

  7. Defining Neighbourhoods as a Measure of Exposure to the Food Environment

    Directory of Open Access Journals (Sweden)

    Anders K. Lyseen

    2015-07-01

    Full Text Available Neighbourhoods are frequently used as a measure for individuals’ exposure to the food environment. However, the definitions of neighbourhoods fluctuate and have not been applied consistently in previous studies. Neighbourhoods defined from a single fixed location fail to capture people’s complete exposure in multiple locations, but measuring behaviour using traditional methods can be challenging. This study compares the traditional methods of measuring exposure to the food environment to methods that use data from GPS tracking. For each of the 187 participants, 11 different neighbourhoods were created in which the exposure to supermarkets and fast food outlets were measured. ANOVA, Tukey’s Honestly Significant Difference (HSD test and t-tests were performed to compare the neighbourhoods. Significant differences were found between area sizes and the exposure to supermarkets and fast food outlets for different neighbourhood types. Second, significant differences in exposure to food outlets were found between the urban and rural neighbourhoods. Neighbourhoods are clearly a diffused and blurred concept that varies in meaning depending on each person’s perception and the conducted study. Complexity and heterogeneity of human mobility no longer appear to correspond to the use of residential neighbourhoods but rather emphasise the need for methods, concepts and measures of individual activity and exposure.

  8. Issues with using radiological exposures as a company performance measure in a low dose environment

    International Nuclear Information System (INIS)

    Wilkins, Richard I.

    2008-01-01

    Full text: Collective and maximum individual doses are two measures commonly used as an indicator for measuring Company performance. There is often an expectation for year on year improvements by optimisation of exposures through improved working methods and modernisation of facilities. Eventually a level of exposure can be reached that is no longer easy to measure which makes meaningful trend analysis difficult. The paper discusses the issues that arose at AWE where the majority of exposures are close the limit of detection for the TLD system used. It details the investigation that was carried out when recorded doses where observed to unexpectedly increase significantly. The paper shows the significant effect of a small change in the background radiation levels that are subtracted for each individual dose measurement. Also discussed is the effect of using TLD dosimeter readers that have undergone recent maintenance and are therefore assessing slightly increased exposures. Compounding the apparent increase in gamma dose a slight change in the manufacturing process for the plastic neutron film in the neutron dosimeters also gave an increased neutron exposure measurement which is detailed. The paper concludes with describing the changes that have been made to better ensure reproducibility of the exposure measurements so that any improvements in Company performance can be shown. It also questions the use of Collective Dose as a performance measure which is commonly misused across the industry. (author)

  9. A case of occupational bile duct carcinoma following exposure to a chlorinated organic solvent in the printing industry that was recognized as a work-related accident.

    Science.gov (United States)

    Fujiyoshi, Toshihisa; Hijioka, Susumu; Imaoka, Hiroshi; Hara, Kazuo; Mizuno, Nobumasa; Tanaka, Tsutomu; Tajika, Masahiro; Shimizu, Yasuhiro; Niwa, Yasumasa; Yamao, Kenji

    2014-12-01

    A man in his 40s presented with liver dysfunction on a screening examination. He was working in the printing industry and had been exposed to a chlorinated organic solvent for 12 years from the age of 20. Detailed examination revealed hilar bile duct cancer; proton radiotherapy was initiated. About three years after completing the proton radiotherapy, recurrence was suspected in hepatic hilar lymph nodes on radiological examination, and he was referred to our hospital. Endoscopic ultrasound-guided fine-needle aspiration of hepatic hilar lymph nodes revealed adenocarcinoma, and systemic chemotherapy was started. Two years later, the lymph nodes showed tumor regrowth, and surgical lymph node resection was performed. To date, 20 months after resection, no recurrence has been identified. We report a case of bile duct carcinoma that was recognized as a work-related accident in an individual working in the printing industry.

  10. Accurate assessment of exposure using tracer gas measurements

    DEFF Research Database (Denmark)

    Kierat, Wojciech; Bivolarova, Mariya; Zavrl, Eva

    2018-01-01

    analyzers with short and long response times, respectively. The tracer gas concentration was characterized by the mean, standard deviation and 95th percentile values. The results revealed that the measurement time needed to determine, with sufficient accuracy, these parameters decreased substantially...

  11. Non-ionizing radiation exposure: electric field strength measurement ...

    African Journals Online (AJOL)

    In this research, the measured values are compared with the international standard recommended by ICNIRP then were also compared with previous study from several locations around Malaysia. The result shows an increase in the values of electromagnetic field radiation. The result of this study could be used for health ...

  12. Organisational measures and medical care after indicents involving radiation exposure

    International Nuclear Information System (INIS)

    Kemmer, W.

    1980-01-01

    West Germany has emergency plans for all kinds of catastrophes, from conventional causes to nuclear accidents. Emergency provisions refer to organisational measures, technical equipment, and medical equipment for the treatment of radiation injuries. These provisions require constant training of responsible persons. Emergency plans and provisions in the Federal Republic of Germany have not been optimized yet. (DG) [de

  13. Accurate measurement of RF exposure from emerging wireless communication systems

    International Nuclear Information System (INIS)

    Letertre, Thierry; Toffano, Zeno; Monebhurrun, Vikass

    2013-01-01

    Isotropic broadband probes or spectrum analyzers (SAs) may be used for the measurement of rapidly varying electromagnetic fields generated by emerging wireless communication systems. In this paper this problematic is investigated by comparing the responses measured by two different isotropic broadband probes typically used to perform electric field (E-field) evaluations. The broadband probes are submitted to signals with variable duty cycles (DC) and crest factors (CF) either with or without Orthogonal Frequency Division Multiplexing (OFDM) modulation but with the same root-mean-square (RMS) power. The two probes do not provide accurate enough results for deterministic signals such as Worldwide Interoperability for Microwave Access (WIMAX) or Long Term Evolution (LTE) as well as for non-deterministic signals such as Wireless Fidelity (WiFi). The legacy measurement protocols should be adapted to cope for the emerging wireless communication technologies based on the OFDM modulation scheme. This is not easily achieved except when the statistics of the RF emission are well known. In this case the measurement errors are shown to be systematic and a correction factor or calibration can be applied to obtain a good approximation of the total RMS power.

  14. Exposure measuring techniques for wide band mobile radio-communications

    International Nuclear Information System (INIS)

    Trinchero, S.; Benedetto, A.; Anglesio, L.; D'Amore, G.; Trinchero, D.

    2004-01-01

    The paper illustrates the limits and performances of different experimental monitoring techniques, which are applied to digitally modulated radiofrequency electromagnetic fields used for mobile telecommunications. Different experimental set-ups have been developed, verified and applied for the analysis and characterisation of wide band probes and narrow band measuring procedures. (authors)

  15. Exposure measurement in the neighboring hospital beds during an x-ray procedure in hospitalization unit

    Energy Technology Data Exchange (ETDEWEB)

    Goto, Rafael E.; Capeleti, Felipe F.; Cabete, Henrique V., E-mail: rafael.goto@fcmsantacasasp.edu.br, E-mail: felipe.capeleti@fcmsantacasasp.edu.br, E-mail: henrique@gmpbrasil.com.br [Faculdade de Ciencias Medicas da Santa Casa Sao Paulo, SP (Brazil); GMP Consultoria em Radioprotecao e Fisica Medica e Assessoria LTDA, Sao Paulo, SP (Brazil)

    2017-11-01

    There are lots of discussion about the exposure in hospitalization units in Brazil, especially around labor legislation and economic advantages of unhealthiness. With the attention focused on hospitalized patients, there were measured the exposure in neighboring beds of the patient submitted to an X-ray procedure with a mobile X-ray system that could be used to illustrate the discussion with consistent values. The most common X-ray procedure made in hospitalization units are chests images with techniques between 70 to 120 kV and 5 to 20 mAs. The measurement was made during routine exposure and simulations using a scattering phantom with Radcal AccuPro electrometer and 1800cc ionization chamber in a private hospital and a philanthropic hospital, both in Sao Paulo, Brazil. The ionization chambers are placed at 2 meters distance of the patient exposed of both sides during the routine procedure. During the simulation, a nylon phantom of 20 centimeters thick and 30 x 30 cm² size was placed on the bed, a typical exposure technique was used and the exposure was measured surrounding the phantom at 0.6, 1.0 and 2.0 meters distance for scattered radiation characterization. Initial results showed that the neighboring exposure at about 2 meters distance from the exposed patient bed have low values, even when exposure is integrated during the length of hospital stay. Therefore, the exposure in hospitalization units are very low compared to the exams doses. (author). (author)

  16. Measurements of Small Exposures of Gamma Radiation with CaSO{sub 4}:Mn Radiothermoluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Bjaerngard, Bengt

    1963-08-15

    A system for measurements of small exposures of gamma radiation using CaSO{sub 4}:Mn thermoluminescence has been developed. The construction and performance of a read-out apparatus is described as well as the construction and characteristics of a simple dosimeter. The reproducibility of the method at various exposures is estimated. 20 {mu}R of 1 MeV gamma radiation can be measured with a reproducibility within {+-} 50 % (standard deviation)

  17. 29 CFR 1915.32 - Toxic cleaning solvents.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Toxic cleaning solvents. 1915.32 Section 1915.32 Labor... Preservation § 1915.32 Toxic cleaning solvents. (a) When toxic solvents are used, the employer shall employ one or more of the following measures to safeguard the health of employees exposed to these solvents. (1...

  18. Comparison of Measures of E-cigarette Advertising Exposure and Receptivity.

    Science.gov (United States)

    Pokhrel, Pallav; Fagan, Pebbles; Herzog, Thaddeus A; Schmid, Simone; Kawamoto, Crissy T; Unger, Jennifer B

    2017-10-01

    We tested how various measures of e-cigarette advertising exposure and receptivity are related to each other and compare to each other in their associations with e-cigarette use susceptibility and behavior. Cross-sectional data were collected from young adult college students (N = 470; M age = 20.9, SD = 2.1; 65% women). Measures of e-cigarette advertising exposure/receptivity compared included a cued recall measure, measures of marketing receptivity, perceived ad exposure, liking of e-cigarette ads, and frequency of convenience store visit, which is considered a measure of point-of-sale ad exposure. The cued-recall measure was associated with e-cigarette use experimentation but not current e-cigarette use. Marketing receptivity was associated with current e-cigarette use but not e-cigarette use experimentation. Liking of e-cigarette ads was the only measure associated with e-cigarette use susceptibility. Frequency of convenience store visit was associated with current e-cigarette use but not e-cigarette use experimentation or susceptibility. Inclusion of multiple measures of marketing exposure and receptivity is recommended for regulatory research concerning e-cigarette marketing. Marketing receptivity and cued recall measures are strong correlates of current and ever e-cigarette use, respectively.

  19. Measurement procedure to assess exposure to extremely low-frequency fields: A primary school case study

    International Nuclear Information System (INIS)

    Alonso, A.; Bahillo, A.; De la Rosa, R.; Carrera, A.; Duran, R. J.; Fernandez, P.

    2012-01-01

    How to correctly measure the exposure of general public to extremely low-frequency (ELF) radiation is a key issue for ELF epidemiological studies. This paper proposes a measurement procedure to accurately assess the exposure of people to electric and magnetic field in the frequency band from 5 Hz to 100 kHz in buildings and their premises. As ELF radiation could be particularly harmful to children, the measurement procedure is focused on exposure to ELF in schools. Thus, the students' exposure to ELF fields can be assessed by correlating the ELF measurements to the hours of school activity. In this paper, the measurement protocol was applied to study the ELF exposure on students from Garcia Quintana primary school in Valladolid, Spain. The campaign of measurements for ELF exposure assessment in this primary school was of great interest for the Regional Council of Public Health because of the social alarm generated by the presence of a significant number cancer cases in children. (authors)

  20. Residential characteristics and radiofrequency electromagnetic field exposures from bedroom measurements in Germany

    DEFF Research Database (Denmark)

    Breckenkamp, J; Blettner, M; Schüz, J

    2012-01-01

    The objectives of this study were to assess total exposure to radiofrequency electromagnetic fields (RF-EMF) in bedrooms and the contribution of different radioservices (FM radio, analogue TV and DVB-T, TETRA, GSM900 downlink, GSM1800 downlink, UMTS downlink, DECT, and wireless LAN and blue tooth......) to the total exposure. Additional aims were to describe the proportion of measuring values above the detection limit of the dosimeters and to characterize the differences in exposure patterns associated with self-reported residential characteristics. Exposure to RF sources in bedrooms was measured using...... Antennessa(®) EME Spy 120 dosimeters in 1,348 households in Germany; 280 measures were available for each frequency band per household. Mean electrical field strengths and power flux densities were calculated. Power flux densities allow the calculation of proportions of different radioservices on total...

  1. Solvents and solvent effects in organic chemistry

    National Research Council Canada - National Science Library

    Reichardt, C; Welton, T

    2011-01-01

    .../guest complexation equilibria and reactions in biphasic solvent systems and neoteric solvents, respectively. More than 900 new references have been added, giving preference to review articles, and many older ones have been deleted. New references either replace older ones or are added to the end of the respective reference list of each chapter. Th...

  2. Sample loading for C-14 measurement in the simulated organic solvent waste from a CANDU Nuclear Power Plant

    International Nuclear Information System (INIS)

    Dianu, Magdalena; Dobrin, Relu; Podina, Corneliu

    2005-01-01

    The paper evaluates the performance of two commercially available liquid scintillation cocktails designed for counting nonaqueous (organic) samples. To choose a suitable scintillation cocktail is not always easy because many cocktails are available on the market. The efficiency, sample loading, sample type are all important variables that help determine the suitability of a liquid scintillation cocktail for C-14 measurement. Samples were counted in a 2100 TRI-CARB Packard Model liquid scintillation analyzer. (authors)

  3. Shared and unshared exposure measurement error in occupational cohort studies and their effects on statistical inference in proportional hazards models

    Science.gov (United States)

    Laurier, Dominique; Rage, Estelle

    2018-01-01

    Exposure measurement error represents one of the most important sources of uncertainty in epidemiology. When exposure uncertainty is not or only poorly accounted for, it can lead to biased risk estimates and a distortion of the shape of the exposure-response relationship. In occupational cohort studies, the time-dependent nature of exposure and changes in the method of exposure assessment may create complex error structures. When a method of group-level exposure assessment is used, individual worker practices and the imprecision of the instrument used to measure the average exposure for a group of workers may give rise to errors that are shared between workers, within workers or both. In contrast to unshared measurement error, the effects of shared errors remain largely unknown. Moreover, exposure uncertainty and magnitude of exposure are typically highest for the earliest years of exposure. We conduct a simulation study based on exposure data of the French cohort of uranium miners to compare the effects of shared and unshared exposure uncertainty on risk estimation and on the shape of the exposure-response curve in proportional hazards models. Our results indicate that uncertainty components shared within workers cause more bias in risk estimation and a more severe attenuation of the exposure-response relationship than unshared exposure uncertainty or exposure uncertainty shared between individuals. These findings underline the importance of careful characterisation and modeling of exposure uncertainty in observational studies. PMID:29408862

  4. Care and supportive measures in school-aged children with prenatal substance exposure.

    Science.gov (United States)

    Sandtorv, Lisbeth B; Haugland, Siren; Elgen, Irene

    2017-12-01

    Prenatal exposure to substances, including alcohol, opiates, and a number of illicit drugs, may have a negative impact on fetal development. Studies have shown that substance exposure can influence a child's neurodevelopment and the need for care and supportive measures. In this study, we aimed to investigate the care status and the level of supportive measures in school-aged children prenatally exposed to alcohol and other substances. This study included children aged between 6 and 14 years who were referred to Haukeland University Hospital in Norway with developmental impairment and a history of prenatal substance exposure. Participants were classified according to their main prenatal exposure to either alcohol or other substances. Information on care status and supportive measures was obtained from medical records and participants' caregivers. We also compared the use of supportive measures for children placed into foster care before and after 1 year of age. A total of 111 (87% of 128 referrals) eligible children participated in the study. Of these 111 children, 96 (86%) were in foster care, of whom 29 (30%) were placed into foster care during their first year of life and 83 out of 90 (92%) had supportive measures, including reinforced foster care and school or social support. A high proportion of the sample lived in foster care and received supportive measures. Findings may reflect an increased need of care and support in school-aged children with prenatal substance exposure, highlighting the importance of awareness among caregivers and public agencies.

  5. Organic Solvent Tropical Report

    International Nuclear Information System (INIS)

    COWLEY, W.L.

    2000-01-01

    This report provides the basis for closing the organic solvent safety issue. Sufficient information is presented to conclude that risk posed by an unmitigated organic solvent fire is within risk evaluation guidelines

  6. Canyon solvent cleaning

    International Nuclear Information System (INIS)

    Reif, D.J.

    1986-01-01

    The HM Process at the Savannah River Plant (SRP) uses 7.5% tributylphosphate in n-paraffin as an extraction solvent. During use, the solvent is altered due to hydrolysis and radiolysis, forming materials that influence product losses, produce decontamination, and separation efficiencies. Laboratory studies to improve online solvent cleaning have shown the carbonate washing, although removing residual solvent activity does not remove binding ligands that hold fission products in the solvent. Treatment of solvent by an alumina adsorption process removes binding ligands and significantly improves recycle solvent performance. Both laboratory work defining a full-scale alumina adsorption process and the use of the process to clean HM Process first cycle solvent are presented

  7. Solvent wash solution

    International Nuclear Information System (INIS)

    Neace, J.C.

    1986-01-01

    This patent describes a process for removing diluent degradation products from a solvent extraction solution comprising an admixture of an organic extractant for uranium and plutonium and a non-polar organic liquid diluent, which has been used to recover uranium and plutonium from spent nuclear fuel. Comprising combining a wash solution consisting of: (a) water; and (b) a positive amount up to about, an including, 50 volume percent of at least one highly-polar water-miscible organic solvent, based on the total volume of the water and the highly-polar organic solvent, with the solvent extraction solution after uranium and plutonium values have been stripped from the solvent extraction solution, the diluent degradation products dissolving in the highly-polar organic solvent and the extractant and diluent of the extraction solution not dissolving in the highly-polar organic solvent, and separating the highly-polar organic solvent and the extraction solution to obtain a purified extraction solution

  8. Instruments to assess and measure personal and environmental radiofrequency-electromagnetic field exposures.

    Science.gov (United States)

    Bhatt, Chhavi Raj; Redmayne, Mary; Abramson, Michael J; Benke, Geza

    2016-03-01

    Radiofrequency-electromagnetic field (RF-EMF) exposure of human populations is increasing due to the widespread use of mobile phones and other telecommunication and broadcasting technologies. There are ongoing concerns about potential short- and long-term public health consequences from RF-EMF exposures. To elucidate the RF-EMF exposure-effect relationships, an objective evaluation of the exposures with robust assessment tools is necessary. This review discusses and compares currently available RF-EMF exposure assessment instruments, which can be used in human epidemiological studies. Quantitative assessment instruments are either mobile phone-based (apps/software-modified and hardware-modified) or exposimeters. Each of these tool has its usefulness and limitations. Our review suggests that assessment of RF-EMF exposures can be improved by using these tools compared to the proxy measures of exposure (e.g. questionnaires and billing records). This in turn, could be used to help increase knowledge about RF-EMF exposure induced health effects in human populations.

  9. Workplace air measurements and likelihood of exposure to manufactured nano-objects, agglomerates, and aggregates

    International Nuclear Information System (INIS)

    Brouwer, Derk H.; Duuren-Stuurman, Birgit van; Berges, Markus; Bard, Delphine; Jankowska, Elzbieta; Moehlmann, Carsten; Pelzer, Johannes; Mark, Dave

    2013-01-01

    Manufactured nano-objects, agglomerates, and aggregates (NOAA) may have adverse effect on human health, but little is known about occupational risks since actual estimates of exposure are lacking. In a large-scale workplace air-monitoring campaign, 19 enterprises were visited and 120 potential exposure scenarios were measured. A multi-metric exposure assessment approach was followed and a decision logic was developed to afford analysis of all results in concert. The overall evaluation was classified by categories of likelihood of exposure. At task level about 53 % showed increased particle number or surface area concentration compared to “background” level, whereas 72 % of the TEM samples revealed an indication that NOAA were present in the workplace. For 54 out of the 120 task-based exposure scenarios, an overall evaluation could be made based on all parameters of the decision logic. For only 1 exposure scenario (approximately 2 %), the highest level of potential likelihood was assigned, whereas in total in 56 % of the exposure scenarios the overall evaluation revealed the lowest level of likelihood. However, for the remaining 42 % exposure to NOAA could not be excluded

  10. Instruments to assess and measure personal and environmental radiofrequency-electromagnetic field exposures

    International Nuclear Information System (INIS)

    Bhatt, Chhavi R.; Redmayne, Mary; Abramson, Michael J.; Benke, Geza

    2016-01-01

    Radiofrequency-electromagnetic field (RF-EMF) exposure of human populations is increasing due to the widespread use of mobile phones and other telecommunication and broadcasting technologies. There are ongoing concerns about potential short- and long-term public health consequences from RF-EMF exposures. To elucidate the RF-EMF exposure-effect relationships, an objective evaluation of the exposures with robust assessment tools is necessary. This review discusses and compares currently available RF-EMF exposure assessment instruments, which can be used in human epidemiological studies. Quantitative assessment instruments are either mobile phone-based (apps/software-modified and hardware-modified) or exposimeters. Each of these tool has its usefulness and limitations. Our review suggests that assessment of RF-EMF exposures can be improved by using these tools compared to the proxy measures of exposure (e.g. questionnaires and billing records). This in turn, could be used to help increase knowledge about RF-EMF exposure induced health effects in human populations.

  11. Solar UV exposure among outdoor workers in Denmark measured with personal UV-B dosimeters

    DEFF Research Database (Denmark)

    Grandahl, Kasper; Mortensen, Ole Steen; Sherman, David Zim

    2017-01-01

    radiation exposure are needed to help resolve this problem. This can be done using personal ultraviolet radiation dosimeters. Methods: We consider technical and practical feasibility of measuring individual solar ultraviolet exposure at work and leisure in professions with different á priori temporal high......-level outdoor worktime, using aluminium gallium nitride (AlGaN) photodiode detector based personal UV-B dosimeters. Essential technical specifications including the spectral and angular responsivity of the dosimeters are described and pre-campaign dosimeter calibration applicability is verified. The scale...... with our specialist knowledge as occupational physicians. Conclusions: Large-scale use of personal UV-B dosimeters for measurement of solar ultraviolet radiation exposure at work and leisure in Denmark is indeed feasible from a technical and practical viewpoint. Samples of exposure data shown support...

  12. An industrial radiography exposure device based on measurement of transmitted gamma-ray intensity

    International Nuclear Information System (INIS)

    Polee, C; Chankow, N; Srisatit, S; Thong-Aram, D

    2015-01-01

    In film radiography, underexposure and overexposure may happen particularly when lacking information of specimen material and hollowness. This paper describes a method and a device for determining exposure in industrial gamma-ray radiography based on quick measurement of transmitted gamma-ray intensity with a small detector. Application software was developed for Android mobile phone to remotely control the device and to display counting data via Bluetooth communication. Prior to film exposure, the device is placed behind a specimen to measure transmitted intensity which is inversely proportional to the exposure. Unlike in using the conventional exposure curve, correction factors for source decay, source-to- film distance, specimen thickness and kind of material are not needed. The developed technique and device make radiographic process economic, convenient and more reliable. (paper)

  13. 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.

  14. Design And Measurement Of Radiation Exposure Rates At An X-Ray Diagnostic Radiological Unit

    International Nuclear Information System (INIS)

    Tito-Sutjipto

    2003-01-01

    Every radiation employees suffers radiation exposure risk while doing his job. It is important therefore to investigate the occupational health and safety of radiation employees on its relationship with the design and measurement of radiation exposure rates at an X-ray diagnostic radiological unit in this work, a case study was held on the radiological unit at BP-4 Yogyakarta for patient diagnostics, This research armed to investigate the relationship between the design of radiological unit for X-ray diagnostics and the location of the X-ray machine, based on the distance variable and radiation exposure rate during patient diagnostics. This was performed using radiological unit design data for X-ray diagnostics and the measurement of radiation exposure rates throughout patient diagnostics. The design data can then be used for determining the requirement of primary and secondary shielding materials for radiological unit as well as a calculation basis of radiation exposure rates during patient diagnostics. From the result of the research, it can be concluded that from the occupational health and safety point of view, radiation exposure around the X-ray machines are fairly good, both for the shielding materials in each X-ray room and the radiation exposures received by the workers, because they are far beyond the maximum permittable average limit (16.67 m R/days). (author)

  15. Predicting personal exposure to airborne carbonyls using residential measurements and time/activity data

    Science.gov (United States)

    Liu, Weili; Zhang, Junfeng (Jim); Korn, Leo R.; Zhang, Lin; Weisel, Clifford P.; Turpin, Barbara; Morandi, Maria; Stock, Tom; Colome, Steve

    As a part of the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study, 48 h integrated residential indoor, outdoor, and personal exposure concentrations of 10 carbonyls were simultaneously measured in 234 homes selected from three US cities using the Passive Aldehydes and Ketones Samplers (PAKS). In this paper, we examine the feasibility of using residential indoor concentrations to predict personal exposures to carbonyls. Based on paired t-tests, the means of indoor concentrations were not different from those of personal exposure concentrations for eight out of the 10 measured carbonyls, indicating indoor carbonyls concentrations, in general, well predicted the central tendency of personal exposure concentrations. In a linear regression model, indoor concentrations explained 47%, 55%, and 65% of personal exposure variance for formaldehyde, acetaldehyde, and hexaldehyde, respectively. The predictability of indoor concentrations on cross-individual variability in personal exposure for the other carbonyls was poorer, explainingexposure concentrations. It was found that activities related to driving a vehicle and performing yard work had significant impacts on personal exposures to a few carbonyls.

  16. [Chemical hazards when working with solvent glues].

    Science.gov (United States)

    Domański, Wojciech; Makles, Zbigniew

    2012-01-01

    Solvent glues are used in a wide variety of industries, e.g., textile, footwear and rubber. The problem of workers' exposure to solvent vapors is rarely tackled within the area of occupational safety and health in small and medium-sized enterprises. In order to assess exposure to solvents, organic solvents emitted by glues were identified in the samples of workplace air. The concentration of acetone, benzene, cyclohexane, ethylbenzene, n-hexane, methylcyclohexane, butyl acetate and toluene were determined. The obtained results evidenced the presence of cyclohexane, ethylbenzene, ethylcyclohexane, heptane, n-hexane, o-xylene, methylcyclohexane, methylcyclopentane, butyl acetate and toluene in workplace air. The concentration of those compounds in workplace air was low, usually below 0.15 of MAC. At some workstations the presence of benzene was also observed. Occupational risk was assessed at workstations where gluing took place. It showed that the risk at those workstations was medium or low.

  17. Broadband measurements of high-frequency electric field levels and exposure ratios determination

    Directory of Open Access Journals (Sweden)

    Vulević Branislav

    2017-01-01

    Full Text Available The exposure of people to high-frequency electromagnetic fields (over 100 kHz that emanate from modern wireless information transmission systems is inevitable in modern times. Due to the rapid development of new technologies, measuring devices and their connection to measuring systems, the first fifteen years of the 21st century are characterized by the appearance of different approaches to measurements. This prompts the need for the assessment of the exposure of people to these fields. The main purpose of this paper is to show how to determine the exposure ratios based on the results of broadband measurements of the high-frequency electric field in the range of 3 MHz to 18 GHz in the environment.

  18. Vitamin D Level in Summer and Winter Related to Measured UVR Exposure and Behavior

    DEFF Research Database (Denmark)

    Thieden, E.; Philipsen, P.A.; Heydenreich, J.

    2009-01-01

    , electronic wristwatch UVR dosimeters and sun exposure diaries. Constitutive and facultative skin pigmentation was measured in September. 25(OH) D was measured in September and February and was in mean 82 nmol/L +/- 25 (mean +/- SD) in September and 56 nmol/L +/- 19 (mean +/- SD) in February. The received...

  19. Instruments to measure radon activity concentration or exposure to radon. Interlaboratory comparison 2011

    International Nuclear Information System (INIS)

    Foerster, Elisabeth; Beck, Thomas; Buchroeder, Helmut; Doering, Joachim; Schmidt, Volkmar

    2011-10-01

    According to the Directive 96/29/EURATOM the monitoring of occupational radiation exposures shall base on individual measurements carried out by an approved dosimetric service. Pursuant to the European Directive an approved dosimetric service is a body responsible for the calibration, reading or interpretation of individual monitoring devices.., whose capacity to act in this respect is recognized by the competent authorities. This concept will also be applied to radon services issuing passive radon measurement devices. Passive radon measurement devices 1 using solid state nuclear track detectors or electrets are recommended for individual monitoring of exposures to radon. German regulations lay down that radon measuring devices are appropriate for purposes of occupational radiation monitoring if the devices are issued by recognized radon measurement services, and the measurement service submits devices of the same type issued for radon monitoring to regular intercomparisons conducted by BfS. A radon measuring service is recognized by the competent authority if it proves its organizational and technical competence, e. g. by accreditation. These regulations have been introduced in the area of occupational radiation exposures. Nevertheless, it is recommended that radon measuring services which carry out radon measurements in other areas (e.g. dwellings) should subject themselves to these measures voluntarily. The interlaboratory comparisons comprise the organization, exposure, and evaluation of measurements of radon activity concentration or exposure to radon. The comparisons only concern radon-222; radon-220 is not in the scope. Radon services being interested can get further information from the website www.bfs.de/de/ion/radon/fachinfomessung/vergleichspruefungen.html and from the European Information System on Proficiency Testing Schemes (eptis) available in the internet. (orig.)

  20. Instruments to measure radon-222 activity concentration or exposure to radon-222. Intercomparison 2014

    International Nuclear Information System (INIS)

    Foerster, Elisabeth; Beck, Thomas; Buchroeder, Helmut; Doering, Joachim; Schmidt, Volkmar

    2014-10-01

    According to the Directive 96/29/EURATOM the monitoring of occupational radiation exposures shall base on individual measurements carried out by an approved dosimetric service. Pursuant to the European Directive an approved dosimetric service is a body responsible for the calibration, reading or interpretation of individual monitoring devices.., whose capacity to act in this respect is recognized by the competent authorities. This concept will also be applied to radon services issuing passive radon measurement devices. Passive radon measurement devices 1 using solid state nuclear track detectors or electrets are recommended for individual monitoring of exposures to radon. German regulations lay down that radon measuring devices are appropriate for purposes of occupational radiation monitoring if the devices are issued by recognized radon measurement services, and the measurement service submits devices of the same type issued for radon monitoring to regular intercomparisons conducted by the Bundesamt fuer Strahlenschutz (BfS). A radon measuring service is recognized by the competent authority if it proves its organisational and technical competence, e. g. by accreditation. These regulations have been introduced in the area of occupational radiation exposures. Nevertheless, it is recommended that radon measuring services which carry out radon measurements in other areas (e.g. dwellings) should subject themselves to these measures voluntarily. The interlaboratory comparisons comprise the organization, exposure, and evaluation of measurements of radon activity concentration or exposure to radon. The comparisons only concern radon-222; radon-220 is not in the scope. Radon services being interested can get further information from the European Information System on Proficiency Testing Schemes (EPTIS) and from the BfS websites.

  1. On the use of mobile phones and wearable microphones for noise exposure measurements: Calibration and measurement accuracy

    Science.gov (United States)

    Dumoulin, Romain

    Despite the fact that noise-induced hearing loss remains the number one occupational disease in developed countries, individual noise exposure levels are still rarely known and infrequently tracked. Indeed, efforts to standardize noise exposure levels present disadvantages such as costly instrumentation and difficulties associated with on site implementation. Given their advanced technical capabilities and widespread daily usage, mobile phones could be used to measure noise levels and make noise monitoring more accessible. However, the use of mobile phones for measuring noise exposure is currently limited due to the lack of formal procedures for their calibration and challenges regarding the measurement procedure. Our research investigated the calibration of mobile phone-based solutions for measuring noise exposure using a mobile phone's built-in microphones and wearable external microphones. The proposed calibration approach integrated corrections that took into account microphone placement error. The corrections were of two types: frequency-dependent, using a digital filter and noise level-dependent, based on the difference between the C-weighted noise level minus A-weighted noise level of the noise measured by the phone. The electro-acoustical limitations and measurement calibration procedure of the mobile phone were investigated. The study also sought to quantify the effect of noise exposure characteristics on the accuracy of calibrated mobile phone measurements. Measurements were carried out in reverberant and semi-anechoic chambers with several mobiles phone units of the same model, two types of external devices (an earpiece and a headset with an in-line microphone) and an acoustical test fixture (ATF). The proposed calibration approach significantly improved the accuracy of the noise level measurements in diffuse and free fields, with better results in the diffuse field and with ATF positions causing little or no acoustic shadowing. Several sources of errors

  2. [Effects of mere exposure on category evaluation measured by the IAT and the GNAT].

    Science.gov (United States)

    Kawakami, Naoaki; Sato, Hirotsune; Yoshida, Fujio

    2010-12-01

    Based on mere exposure studies, we proposed that repeated exposure to stimuli belonging to a common category leads to a positive evaluation of that category. Furthermore, to investigate the implicit effects of mere exposure, indirect measures were used. In a series of experiments, participants were repeatedly exposed to mimetic words written in Japanese hiragana or katakana, or nothing (control). Then their evaluations of the category ("hiragana" or "katakana") were measured using indirect and direct measures. In Experiment 1 (Implicit Association Test; IAT), we adopted a traditional design using an exposure paradigm, such that the rating stimuli were identical to the exposed stimuli. Significant effects were observed for both measures. In Experiment 2 (IAT) and Experiment 3 (Go/No-go Association Task; GNAT), we used non-exposed stimuli that belonged to a common category as the rating stimuli. Significant effects were observed only for indirect measures. These results indicate that repeated exposure has unconscious positive effects on category evaluation. Theoretical and methodological implications of the findings are discussed.

  3. Sequential Measurement of Intermodal Variability in Public Transportation PM2.5 and CO Exposure Concentrations.

    Science.gov (United States)

    Che, W W; Frey, H Christopher; Lau, Alexis K H

    2016-08-16

    A sequential measurement method is demonstrated for quantifying the variability in exposure concentration during public transportation. This method was applied in Hong Kong by measuring PM2.5 and CO concentrations along a route connecting 13 transportation-related microenvironments within 3-4 h. The study design takes into account ventilation, proximity to local sources, area-wide air quality, and meteorological conditions. Portable instruments were compacted into a backpack to facilitate measurement under crowded transportation conditions and to quantify personal exposure by sampling at nose level. The route included stops next to three roadside monitors to enable comparison of fixed site and exposure concentrations. PM2.5 exposure concentrations were correlated with the roadside monitors, despite differences in averaging time, detection method, and sampling location. Although highly correlated in temporal trend, PM2.5 concentrations varied significantly among microenvironments, with mean concentration ratios versus roadside monitor ranging from 0.5 for MTR train to 1.3 for bus terminal. Measured inter-run variability provides insight regarding the sample size needed to discriminate between microenvironments with increased statistical significance. The study results illustrate the utility of sequential measurement of microenvironments and policy-relevant insights for exposure mitigation and management.

  4. Measurement and correlation of the solubility of 3,4-bis(3-nitrofurazan-4-yl)furoxan (DNTF) in different solvents

    International Nuclear Information System (INIS)

    Lan, Guan-Chao; Wang, Jian-Long; Chen, Li-Zhen; Hou, Huan; Li, Jing; Gao, Yu-Peng

    2015-01-01

    Highlights: • The laser monitoring system was used for measuring the solubilities of DNTF. • Three correlation equations were adopted to correlate the experimental values. • The three-dimensional figure between ln x i and 1/T, ln T was obtained. • Thermodynamic properties were calculated by the experimental solubilities. - Abstract: A knowledge of the solubility of 3,4-bis(3-nitrofurazan-4-yl)furoxan (DNTF) in different solvents is essential for crystallization and further theoretical studies. The laser monitoring system was used for measuring the solubility of DNTF in methanol, ethanol, acetic acid, benzene, toluene and n-butanol at temperatures ranging from (298.15 to 338.15) K. Polynomial empirical equation, ideal model and modified Apelblat equation were used to correlate the experimental values. The correlated results of three correlation equations present good consistency with the experimental values. In addition, the modified Apelblat equation produced higher accuracy than the polynomial empirical equation and the ideal equation. The standard dissolution enthalpy, standard dissolution entropy and the Gibbs energy were calculated from the experimental values. The solubility values of DNTF and correlation equations from this experiment would be invoked as basic data and models regarding the crystallization process of DNTF

  5. Understanding the exposure-time effect on speckle contrast measurements for laser displays

    Science.gov (United States)

    Suzuki, Koji; Kubota, Shigeo

    2018-02-01

    To evaluate the influence of exposure time on speckle noise for laser displays, speckle contrast measurement method was developed observable at a human eye response time using a high-sensitivity camera which has a signal multiplying function. The nonlinearity of camera light sensitivity was calibrated to measure accurate speckle contrasts, and the measuring lower limit noise of speckle contrast was improved by applying spatial-frequency low pass filter to the captured images. Three commercially available laser displays were measured over a wide range of exposure times from tens of milliseconds to several seconds without adjusting the brightness of laser displays. The speckle contrast of raster-scanned mobile projector without any speckle-reduction device was nearly constant over various exposure times. On the contrary to this, in full-frame projection type laser displays equipped with a temporally-averaging speckle-reduction device, some of their speckle contrasts close to the lower limits noise were slightly increased at the shorter exposure time due to the noise. As a result, the exposure-time effect of speckle contrast could not be observed in our measurements, although it is more reasonable to think that the speckle contrasts of laser displays, which are equipped with the temporally-averaging speckle-reduction device, are dependent on the exposure time. This discrepancy may be attributed to the underestimation of temporal averaging factor. We expected that this method is useful for evaluating various laser displays and clarify the relationship between the speckle noise and the exposure time for a further verification of speckle reduction.

  6. 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)

  7. Self-reported hearing performance in workers exposed to solvents

    Directory of Open Access Journals (Sweden)

    Adrian Fuente

    2013-02-01

    Full Text Available OBJECTIVE: To compare hearing performance relating to the peripheral and central auditory system between solvent-exposed and non-exposed workers. METHODS: Forty-eight workers exposed to a mixture of solvents and 48 non-exposed control subjects of matched age, gender and educational level were selected to participate in the study. The evaluation procedures included: pure-tone audiometry (500 - 8,000 Hz, to investigate the peripheral auditory system; the Random Gap Detection test, to assess the central auditory system; and the Amsterdam Inventory for Auditory Disability and Handicap, to investigate subjects' self-reported hearing performance in daily-life activities. A Student t test and analyses of covariance (ANCOVA were computed to determine possible significant differences between solvent-exposed and non-exposed subjects for the hearing level, Random Gap Detection test and Amsterdam Inventory for Auditory Disability and Handicap. Pearson correlations among the three measures were also calculated. RESULTS: Solvent-exposed subjects exhibited significantly poorer hearing thresholds for the right ear than non-exposed subjects. Also, solvent-exposed subjects exhibited poorer results for the Random Gap Detection test and self-reported poorer listening performance than non-exposed subjects. Results of the Amsterdam Inventory for Auditory Disability and Handicap were significantly correlated with the binaural average of subject pure-tone thresholds and Random Gap Detection test performance. CONCLUSIONS: Solvent exposure is associated with poorer hearing performance in daily life activities that relate to the function of the peripheral and central auditory system.

  8. Monitoring method for an ambient Gamma exposure rate and its measurement analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Mo Sung [Cheongju Univ., Cheongju (Korea, Republic of); Woo, Jong Kwan [University of Seoul, Seoul (Korea, Republic of)

    2006-12-15

    Daily and seasonal variations of the ambient gamma ray exposure rates were measured by using a pressurized ion chamber from January 2003 to December 2005 in the Cheongju Regional Radiation Monitoring Post and the patterns of the distributions were studied. The annual average of the daily variation of the exposure rate was {approx}0.17 {mu}R/h. The exposure rate was found to be maximum during 8:00 am to 9:00 am and minimum during 8:00 pm to 10:00 pm. For the annual data, the exposure rate was the minimum during the month of February. The exposure rate increased from February to mid-October (except during the period from May to July with no change) and decreased from October to February. The seasonal variation was found to be about 1 {mu}R/h. Most of the measured values (96%) of the exposure rates fell under the normal distribution with a deviation of less than 4.8% and the remaining 4% had large fluctuations caused mainly by the rainfalls.

  9. MEASUREMENT OF PYRETHROID RESIDUES IN ENVIRONMENTAL AND FOOD SAMPLES BY ENHANCED SOLVENT EXTRACTION/SUPERCRITICAL FLUID EXTRACTION COUPLED WITH GAS CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY

    Science.gov (United States)

    The abstract summarizes pyrethorid methods development research. It provides a summary of sample preparation and analytical techniques such as supercritical fluid extraction, enhance solvent extraction, gas chromatography and tandem mass spectrometry.

  10. Measurements of indoor and outdoor natural radiation exposure rates in model houses

    International Nuclear Information System (INIS)

    Matsuda, Hideharu; Fukaya, Mitsuharu; Minato, Susumu

    1990-01-01

    Natural gamma-ray and cosmic-ray exposure rates were measured indoors and outdoors for 94 model houses of four housing centers in Nagoya to obtain basic data for estimation of the population dose. Influence of the structure of houses on indoor exposure rates and relationship between indoor and outdoor natural gamma-ray exposure rates were studied. Exposure rates were measured with a 1.5'' φ x 4'' NaI (Tl) scintillation counter and a 6''φ spherical plastic scintillation counter. The mean indoor natural gamma-ray exposure rate in ferro-concrete buildings was about 40% higher than that in fireproof wooden houses, about 60% higher than that in light-weight steel-framed buildings, in fireproof wooden houses, it was also about 10% higher than in light-weight steel-framed building. The ratio of indoor to outdoor natural gamma-ray exposure rate was found to be about 0.95±0.15, 0.77±0.10, and 0.72±0.13 for ferro-concrete buildings, fireproof wooden houses and light-weight steel-framed buildings, respectively. The mean indoor cosmic-ray exposure rate in ferro-concrete buildings was 2.8 μR/h, about 18% lower than the outdoors. The indoor cosmic-ray exposure rate in fireproof wooden houses and light-weight steel-framed buildings were 3.2 μR/h, about 6% lower than the outdoors. (author)

  11. Measurements of natural radiation exposure rates in various living environment, (2)

    International Nuclear Information System (INIS)

    Matsuda, Hideharu

    1991-01-01

    Natural gamma-ray and cosmic-ray exposure rates were measured indoors and outdoors for 94 model houses of housing exhibition centers in Nagoya to obtain basic data for estimation of the population dose. Influence of the structure of houses on indoor exposure rates and relationship between indoor and outdoor natural gamma-ray exposure rates were studied. Exposure rates were measured with a 1.5''φ x 4''NaI(Tl) scintillation counter and a 6''φ spherical plastic scintillation counter. The mean indoor natural gamma-ray exposure rate in ferro-concrete buildings was about 40 % higher than that in fire-proof wooden houses and about 60 % higher than that in light weight steel framed buildings; that in fire-proof wooden houses was about 10 % higher than that in light weight steel framed buildings. The ratio of indoor to outdoor natural gamma-ray exposure rate was found to be 0.95 ± 0.15, 0.77 ± 0.10 and 0.72 ± 0.13 for ferro-concrete buildings, fire-proof wooden houses and light weight steel framed buildings, respectively. The mean indoor cosmic-ray exposure rate in ferro-concrete buildings was 2.8 μR/h, which was about 18 % lower than the outdoor value. The indoor cosmic-ray exposure rate both in fire-proof wooden houses and in light weight steel framed buildings were about 3.2 μR/h, which was 6 % lower than the outdoor value. (author)

  12. In vivo measurements of lead-210 for assessing cumulative radon exposure in uranium miners

    Energy Technology Data Exchange (ETDEWEB)

    Guilmette, R.A.; Laurer, G.R. [New York Univ. Inst. of Environmental Medicine, Tuxedo, NY (United States); Lambert, W.E.; Gilliland, F.D. [Univ. of New Mexico, Albuquerque, NM (United States)] [and others

    1995-12-01

    It has long been recognized that a major contributor to the uncertainty in risk analysis of lung cancer in uranium and other hard rock miners is the estimation of total radon progeny exposure of individual miners under study. These uncertainties arise from the fact that only a limited number of measurements of airborne {sup 222}Rn progeny concentrations were made in the mines during the times that the miners were being exposed, and that dosimeters capable of integrating the Rn progeny exposures of the miners did not exist. Historically, the cumulative exposures for individual uranium and other hard rock miners have been calculated by combining the employee`s work history, which may or may not have included time spent at different jobs within the mines and at different locations within the mines, with whatever periodic measurements of Rn and Rn progeny were available. The amount and quality of the measurement data varied enormously from mine to mine and from population to population. Because the quality of the exposure data collected during the period of active mining in the United STates cannot now be altered substantially, significant improvement in individual miner exposure estimates is only likely to be achieved if a new cumulative exposure metric is developed and implemented. The decay chain of Rn includes the production of {sup 210}Pb, which can accumulate in the skeleton in amounts proportional to the intake of Rn progeny. We hypothesize that the in vivo measurement of {sup 210}Pb in the skulls of miners will provide such a metric. In summary, the primary purpose of this pilot study to demonstrate the feasibility of measuring {sup 210}Pb in the heads of former uranium miners has been accomplished.

  13. In vivo measurements of lead-210 for assessing cumulative radon exposure in uranium miners

    International Nuclear Information System (INIS)

    Guilmette, R.A.; Laurer, G.R.; Lambert, W.E.; Gilliland, F.D.

    1995-01-01

    It has long been recognized that a major contributor to the uncertainty in risk analysis of lung cancer in uranium and other hard rock miners is the estimation of total radon progeny exposure of individual miners under study. These uncertainties arise from the fact that only a limited number of measurements of airborne 222 Rn progeny concentrations were made in the mines during the times that the miners were being exposed, and that dosimeters capable of integrating the Rn progeny exposures of the miners did not exist. Historically, the cumulative exposures for individual uranium and other hard rock miners have been calculated by combining the employee's work history, which may or may not have included time spent at different jobs within the mines and at different locations within the mines, with whatever periodic measurements of Rn and Rn progeny were available. The amount and quality of the measurement data varied enormously from mine to mine and from population to population. Because the quality of the exposure data collected during the period of active mining in the United STates cannot now be altered substantially, significant improvement in individual miner exposure estimates is only likely to be achieved if a new cumulative exposure metric is developed and implemented. The decay chain of Rn includes the production of 210 Pb, which can accumulate in the skeleton in amounts proportional to the intake of Rn progeny. We hypothesize that the in vivo measurement of 210 Pb in the skulls of miners will provide such a metric. In summary, the primary purpose of this pilot study to demonstrate the feasibility of measuring 210 Pb in the heads of former uranium miners has been accomplished

  14. Predicting Return of Fear Following Exposure Therapy With an Implicit Measure of Attitudes

    Science.gov (United States)

    Vasey, Michael W.; Harbaugh, Casaundra N.; Buffington, Adam G.; Jones, Christopher R.; Fazio, Russell H.

    2012-01-01

    We sought to advance understanding of the processes underlying the efficacy of exposure therapy and particularly the phenomenon of return of fear (ROF) following treatment by drawing on a social psychological view of phobias as attitudes. Specifically, a dual process theory of attitude-related behavior predicts that a positive response to exposure therapy may reflect change in either the automatic (the attitude representation itself) or controlled (skills and confidence at coping with the fear) responses to the phobic stimulus, or both. However, if the attitude representation remains negative following treatment, ROF should be more likely. We tested this hypothesis in a clinical sample of individuals with public speaking phobia using a single-session exposure therapy protocol previously shown to be efficacious but also associated with some ROF. Consistent with predictions, a post-treatment implicit measure of attitudes toward public speaking (the Personalized Implicit Association Test [PIAT]) predicted ROF at 1-month follow-up. These results suggest that change in the automatically activated attitude toward the phobic stimulus is an important goal of exposure therapy and that an implicit measure like the PIAT can provide a useful measure of such change by which to gauge the adequacy of exposure treatment and predict its long-term efficacy. PMID:23085186

  15. Measurement of environmental radiation exposure rates from Vernita, Hanford Reach, and Richland area shores. Addendum 1

    International Nuclear Information System (INIS)

    Cooper, A.T.

    1995-02-01

    Environmental radiation exposure rate measurements are taken on and around the Hanford Site for Pacific Northwest Laboratory's Hanford Site Surface Environmental Surveillance Project. In 1992, environmental radiation exposure rate measurements were taken from shoreline and island areas ranging from Vernita, along the Hanford Reach, down to the Richland Pumphouse. Measurements were taken primarily at locations known or expected to have elevated exposure rates as determined by examination of aerial photographs depicting radiation exposure measurements. Results from the 1992 survey indicated radiation exposure rates taken from the Hanford Reach area were elevated in comparison to the measurements taken from the Vernita area with ranges of 8 to 28 μR/hr and 4 to 11 μR/hr, respectively. In January 1994, additional shoreline radiation exposure rate measurements were taken from the Vernita, Hanford Reach, and Richland areas to determine the relationship of radiation exposure rates along the Richland area shores when compared to Vernita and Hanford Reach area exposure rates (measurements along the Richland area were not collected during the 1992 survey). This report discusses the 1994 results and is an addendum to the report that discussed the 1992 survey. An analysis of variance indicated a significant location interaction at a p-value of 0.0014. To determine differences between paried locations a post-hoc comparison of location means was performed on log transformed data using the Scheffacute e's F-test. This test indicated a significant difference between Hanford Reach and Richland area means with a mean difference of 0.075 /μR/hr and a p-value of 0.0014. No significant difference was found between Hanford Reach and Vernita area means: The mean difference was 0.031 μR/hr and the p-value was 0.3138. No significant difference was found between Vernita and Richland area means with a mean difference of 0.044 μR/hr and a p-value of 0.1155

  16. Solvent neurotoxicity in vehicle collision repair workers in New Zealand.

    Science.gov (United States)

    Keer, Samuel; Glass, Bill; Prezant, Bradley; McLean, David; Pearce, Neil; Harding, Elizabeth; Echeverria, Diana; McGlothlin, James; Babbage, Duncan R; Douwes, Jeroen

    2016-12-01

    To assess whether solvent use and workplace practices in the vehicle collision repair industry are associated with symptoms of neurotoxicity in spray painters and panel beaters (auto body repair workers). Neurobehavioural symptoms were assessed using a cross-sectional study design in 370 vehicle collision repair and 211 reference workers using the EUROQUEST questionnaire. Full-shift airborne solvent levels were measured in a subset (n=92) of collision repair workers. Solvent exposures were higher in spray painters than in panel beaters, but levels were below current international exposure standards. Collision repair workers were more likely to report symptoms of neurotoxicity than reference workers with ORs of 2.0, 2.4 and 6.4 (all p<0.05) for reporting ≥5, ≥10 and ≥15 symptoms respectively. This trend was generally strongest for panel beaters (ORs of 2.1, 3.3 and 8.2 for ≥5, ≥10 and ≥15 symptoms respectively). Associations with specific symptom domains showed increased risks for neurological (OR 4.2), psychosomatic (OR 3.2), mood (OR 2.1), memory (OR 2.9) and memory and concentration symptoms combined (OR 2.4; all p<0.05). Workers who had worked for 10-19 years or 20+ years in the collision repair industry reported consistently more symptoms than those who had only worked less than 10 years even after adjusting for age. However, those who worked more than 20 years generally reported fewer symptoms than those who worked 10-19 years, suggesting a possible healthy worker survivor bias. Despite low airborne solvent exposures, vehicle collision repair spray painters and panel beaters continue to be at risk of symptoms of neurotoxicity. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Combining Lead Exposure Measurements and Experts' Judgment Through a Bayesian Framework.

    Science.gov (United States)

    Koh, Dong-Hee; Park, Ju-Hyun; Lee, Sang-Gil; Kim, Hwan-Cheol; Choi, Sangjun; Jung, Hyejung; Park, Dong-Uk

    2017-11-10

    CARcinogen EXposure (CAREX) is a carcinogen-surveillance system employed in many countries. To develop Korean CAREX, the intensity of exposure to lead, as an example, was estimated across industries. Airborne-lead measurement records were extracted from the work-environment measurement database (WEMD), which is a nationwide workplace-monitoring database. Lead measurements were log-transformed; then, the log-transformed geometric means (LGMs) and log-transformed geometric standard deviations (LGSDs) were calculated for each industry. However, the data of many industries was limited. To address this shortcoming, experts' judgments of the lead exposure levels across industries were elicited. Experts provided their estimates of lead exposure levels as the boundary of the 5th and 95th percentiles, and it is assumed that these estimates are based on the log-normal distributions of exposure levels. Estimates of LGM and LGSD were extracted from each expert's response and then combined to quantify the experts' prior distribution. Then, the experts' prior distributions for each industry were updated with the corresponding LGMs and LGSDs calculated from the WEMD data through a Bayesian framework, yielding posterior distributions of the LGM and LGSD. The WEMD contains 83035 airborne-lead measurements that were collected between 2002 and 2007. A total of 17 occupational-hygiene professionals with >20 years of experience provided lead exposure estimates. In industries where measurement data were abundant, the measurement data dominated the posterior exposure estimates. For example, for one industry, 'Manufacture of Accumulator, Primary Cells, and Primary Batteries,' 1152 lead measurements [with a geometric mean (GM) of 14.42 µg m-3 and a geometric standard deviation (GSD) of 3.31] were available and 15 experts' responses (with a GM of 7.06 µg m-3 and a GSD of 4.15) were collected, resulting in a posterior exposure estimate of 14.41µg m-3 as the GM with a GSD of 3.31. For

  18. 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)

  19. In-situ real time measurements of net erosion rates of copper during hydrogen plasma exposure

    Science.gov (United States)

    Kesler, Leigh; Wright, Graham; Peterson, Ethan; Whyte, Dennis

    2013-10-01

    In order to properly understand the dynamics of net erosion/deposition in fusion reactors, such as tokamaks, a diagnostic measuring the real time rates of net erosion/deposition during plasma exposure is necessary. The DIONISOS experiment produces real time measurements of net erosion/deposition by using Rutherford backscattering spectroscopy (RBS) ion beam analysis simultaneously with plasma exposure from a helicon plasma source. This in-situ method improves on ex-situ weight loss measurements by allowing measurement of possible synergistic effects of high ion implantation rates and net erosion rate and by giving a real time response to changes in plasma parameters. Previous work has validated this new technique for measuring copper (Cu) erosion from helium (He) plasma ion bombardment. This technique is now extended to measure copper erosion due to deuterium and hydrogen plasma ion exposure. Targets used were a 1.5 μm Cu layer on an aluminum substrate. Cu layer thickness is tracked in real time using 1.2 MeV proton RBS. Measured erosion rates will be compared to results from literature and He erosion rates. Supported by US DoE award DE-SC00-02060.

  20. Harmonization of measurement strategies for exposure to manufactured nano-objects; Report of a workshop

    NARCIS (Netherlands)

    Brouwer, D.; Berges, M.; Virji, M.A.; Fransman, W.; Bello, D.; Hodson, L.; Gabriel, S.; Tielemans, E.

    2012-01-01

    The present paper summarizes the outcome of the discussions at the First International Scientific Workshop on Harmonization of Strategies to Measure and Analyze Exposure to (Manufactured) Nano-objects in Workplace Air that was organized and hosted by the Netherlands Organization for Applied

  1. Cosmic radiation exposure of aircraft crew: compilation of measured and calculated data

    Czech Academy of Sciences Publication Activity Database

    Lindborg, L.; Bartlett, D.; Beck, P.; McAulay, I.; Schnuer, K.; Schraube, H.; Spurný, František

    2004-01-01

    Roč. 110, 1-4 (2004), s. 417-422 ISSN 0144-8420 Grant - others:EC project(XE) FIGM-CT2000-00068 Institutional research plan: CEZ:AV0Z1048901 Keywords : cosmic radiation exposure * aircraft crew * measurement Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.617, year: 2003

  2. Bias and power in group-based epidemiologic studies of low-back pain exposure and outcome - Effects of study size and exposure measurement efforts

    NARCIS (Netherlands)

    Coenen, P.; Mathiassen, S.E.; Kingma, I.; Boot, C.R.L.; Bongers, P.M.; Dieën, J.H. van

    2015-01-01

    Objectives: Exposure-outcome studies, for instance on work-related low-back pain (LBP), often classify workers into groups for which exposures are estimated from measurements on a sample of workers within or outside the specific study. The present study investigated the influence on bias and power

  3. Background Noise Contributes to Organic Solvent Induced Brain Dysfunction

    Directory of Open Access Journals (Sweden)

    O’neil W. Guthrie

    2016-01-01

    Full Text Available Occupational exposure to complex blends of organic solvents is believed to alter brain functions among workers. However, work environments that contain organic solvents are also polluted with background noise which raises the issue of whether or not the noise contributed to brain alterations. The purpose of the current study was to determine whether or not repeated exposure to low intensity noise with and without exposure to a complex blend of organic solvents would alter brain activity. Female Fischer344 rats served as subjects in these experiments. Asynchronous volume conductance between the midbrain and cortex was evaluated with a slow vertex recording technique. Subtoxic solvent exposure, by itself, had no statistically significant effects. However, background noise significantly suppressed brain activity and this suppression was exacerbated with solvent exposure. Furthermore, combined exposure produced significantly slow neurotransmission. These abnormal neurophysiologic findings occurred in the absence of hearing loss and detectable damage to sensory cells. The observations from the current experiment raise concern for all occupations where workers are repeatedly exposed to background noise or noise combined with organic solvents. Noise levels and solvent concentrations that are currently considered safe may not actually be safe and existing safety regulations have failed to recognize the neurotoxic potential of combined exposures.

  4. Background Noise Contributes to Organic Solvent Induced Brain Dysfunction

    Science.gov (United States)

    Guthrie, O'neil W.; Wong, Brian A.; McInturf, Shawn M.; Reboulet, James E.; Ortiz, Pedro A.; Mattie, David R.

    2016-01-01

    Occupational exposure to complex blends of organic solvents is believed to alter brain functions among workers. However, work environments that contain organic solvents are also polluted with background noise which raises the issue of whether or not the noise contributed to brain alterations. The purpose of the current study was to determine whether or not repeated exposure to low intensity noise with and without exposure to a complex blend of organic solvents would alter brain activity. Female Fischer344 rats served as subjects in these experiments. Asynchronous volume conductance between the midbrain and cortex was evaluated with a slow vertex recording technique. Subtoxic solvent exposure, by itself, had no statistically significant effects. However, background noise significantly suppressed brain activity and this suppression was exacerbated with solvent exposure. Furthermore, combined exposure produced significantly slow neurotransmission. These abnormal neurophysiologic findings occurred in the absence of hearing loss and detectable damage to sensory cells. The observations from the current experiment raise concern for all occupations where workers are repeatedly exposed to background noise or noise combined with organic solvents. Noise levels and solvent concentrations that are currently considered safe may not actually be safe and existing safety regulations have failed to recognize the neurotoxic potential of combined exposures. PMID:26885406

  5. Background Noise Contributes to Organic Solvent Induced Brain Dysfunction.

    Science.gov (United States)

    Guthrie, O'neil W; Wong, Brian A; McInturf, Shawn M; Reboulet, James E; Ortiz, Pedro A; Mattie, David R

    2016-01-01

    Occupational exposure to complex blends of organic solvents is believed to alter brain functions among workers. However, work environments that contain organic solvents are also polluted with background noise which raises the issue of whether or not the noise contributed to brain alterations. The purpose of the current study was to determine whether or not repeated exposure to low intensity noise with and without exposure to a complex blend of organic solvents would alter brain activity. Female Fischer344 rats served as subjects in these experiments. Asynchronous volume conductance between the midbrain and cortex was evaluated with a slow vertex recording technique. Subtoxic solvent exposure, by itself, had no statistically significant effects. However, background noise significantly suppressed brain activity and this suppression was exacerbated with solvent exposure. Furthermore, combined exposure produced significantly slow neurotransmission. These abnormal neurophysiologic findings occurred in the absence of hearing loss and detectable damage to sensory cells. The observations from the current experiment raise concern for all occupations where workers are repeatedly exposed to background noise or noise combined with organic solvents. Noise levels and solvent concentrations that are currently considered safe may not actually be safe and existing safety regulations have failed to recognize the neurotoxic potential of combined exposures.

  6. An instantaneous spatiotemporal model to predict a bicyclist's Black Carbon exposure based on mobile noise measurements

    Science.gov (United States)

    Dekoninck, Luc; Botteldooren, Dick; Int Panis, Luc

    2013-11-01

    Several studies have shown that a significant amount of daily air pollution exposure, in particular Black Carbon (BC), is inhaled during trips. Assessing this contribution to exposure remains difficult because on the one hand local air pollution maps lack spatio-temporal resolution, at the other hand direct measurement of particulate matter concentration remains expensive. This paper proposes to use in-traffic noise measurements in combination with geographical and meteorological information for predicting BC exposure during commuting trips. Mobile noise measurements are cheaper and easier to perform than mobile air pollution measurements and can easily be used in participatory sensing campaigns. The uniqueness of the proposed model lies in the choice of noise indicators that goes beyond the traditional overall A-weighted noise level used in previous work. Noise and BC exposures are both related to the traffic intensity but also to traffic speed and traffic dynamics. Inspired by theoretical knowledge on the emission of noise and BC, the low frequency engine related noise and the difference between high frequency and low frequency noise that indicates the traffic speed, are introduced in the model. In addition, it is shown that splitting BC in a local and a background component significantly improves the model. The coefficients of the proposed model are extracted from 200 commuter bicycle trips. The predicted average exposure over a single trip correlates with measurements with a Pearson coefficient of 0.78 using only four parameters: the low frequency noise level, wind speed, the difference between high and low frequency noise and a street canyon index expressing local air pollution dispersion properties.

  7. Exhaled human breath measurement method for assessing exposure to halogenated volatile organic compounds.

    Science.gov (United States)

    Pleil, J D; Lindstrom, A B

    1997-05-01

    The organic constituents of exhaled human breath are representative of blood-borne concentrations through gas exchange in the blood/breath interface in the lungs. The presence of specific compounds can be an indicator of recent exposure or represent a biological response of the subject. For volatile organic compounds (VOCs), sampling and analysis of breath is preferred to direct measurement from blood samples because breath collection is noninvasive, potentially infectious waste is avoided, and the measurement of gas-phase analytes is much simpler in a gas matrix rather than in a complex biological tissue such as blood. To exploit these advantages, we have developed the "single breath canister" (SBC) technique, a simple direct collection method for individual alveolar breath samples, and adapted conventional gas chromatography-mass spectrometry analytical methods for trace-concentration VOC analysis. The focus of this paper is to describe briefly the techniques for making VOC measurements in breath, to present some specific applications for which these methods are relevant, and to demonstrate how to estimate exposure to example VOCs on the basis of breath elimination. We present data from three different exposure scenarios: (a) vinyl chloride and cis-1,2-dichloroethene from showering with contaminated water from a private well, (b) chloroform and bromodichloromethane from high-intensity swimming in chlorinated pool water, and (c) trichloroethene from a controlled exposure chamber experiment. In all cases, for all subjects, the experiment is the same: preexposure breath measurement, exposure to halogenated VOC, and a postexposure time-dependent series of breath measurements. Data are presented only to demonstrate the use of the method and how to interpret the analytical results.

  8. Oslo traffic study - part 2: quantifying effects of traffic measures using individual exposure modeling

    International Nuclear Information System (INIS)

    Clench-Aas, J.; Bartonova, A.; Klaeboe, R.; Kolbenstvedt, M.

    2000-01-01

    In quantifying the benefits of air pollution reduction measures, it is desirable to compare the size of the benefits with the effects of other individual confounding factors such as smoking or passive smoking. The effect of pollution is rarely very large and in order to quantify it, exposure estimating procedures must be as accurate as possible. Dispersion models, run for hourly time intervals and controlled by measurements, are therefore used to provide estimates for specific receptor points. Results of three consecutive cross-sectional investigations in an area of Oslo characterized by heavy traffic are presented. The study was designed to provide repeated information on the effects of traffic diversion measures on the self-reporting of symptoms of reduced health of 1100 adults living in Oslo. The principal source of air pollution in Oslo is vehicular traffic. The primary pollutants of interest are nitrogen dioxide (NO 2 ) and respirable particles (PM 2.5 and PM 10 ). The mean hourly concentration of exposure was estimated at each participant's home by means of a time-dependent finite dispersion model combined with subgrid models to describe the source contribution to the grid concentrations. The study controlled the confounding factors. Using the symptom fatigue, the study illustrates that by controlling the changes in population composition, estimated exposure-effect relationships for health symptoms allow the effect of the studied traffic measures on the population to be evaluated. Since the method is based on individual estimates of exposure to different pollutants, it allows standardizing the exposure to compare effects of different pollutants. The study offers a methodology that is useful in evaluating the benefits of measures by both being able to quantify and compare the effects of different compounds and effects on different population sub-groups. (author)

  9. Incorporating Measurement Error from Modeled Air Pollution Exposures into Epidemiological Analyses.

    Science.gov (United States)

    Samoli, Evangelia; Butland, Barbara K

    2017-12-01

    Outdoor air pollution exposures used in epidemiological studies are commonly predicted from spatiotemporal models incorporating limited measurements, temporal factors, geographic information system variables, and/or satellite data. Measurement error in these exposure estimates leads to imprecise estimation of health effects and their standard errors. We reviewed methods for measurement error correction that have been applied in epidemiological studies that use model-derived air pollution data. We identified seven cohort studies and one panel study that have employed measurement error correction methods. These methods included regression calibration, risk set regression calibration, regression calibration with instrumental variables, the simulation extrapolation approach (SIMEX), and methods under the non-parametric or parameter bootstrap. Corrections resulted in small increases in the absolute magnitude of the health effect estimate and its standard error under most scenarios. Limited application of measurement error correction methods in air pollution studies may be attributed to the absence of exposure validation data and the methodological complexity of the proposed methods. Future epidemiological studies should consider in their design phase the requirements for the measurement error correction method to be later applied, while methodological advances are needed under the multi-pollutants setting.

  10. Respiratory Health - Exposure Measurements and Modeling in the Fragrance and Flavour Industry.

    Science.gov (United States)

    Angelini, Eric; Camerini, Gerard; Diop, Malick; Roche, Patrice; Rodi, Thomas; Schippa, Christine; Thomas, Thierry

    2016-01-01

    Although the flavor and fragrance industry is about 150 years old, the use of synthetic materials started more than 100 years ago, and the awareness of the respiratory hazard presented by some flavoring substances emerged only recently. In 2001, the US National Institute of Occupational Safety and Health (NIOSH) identified for the first time inhalation exposure to flavoring substances in the workplace as a possible occupational hazard. As a consequence, manufacturers must comply with a variety of workplace safety requirements, and management has to ensure the improvement of health and safety of the employees exposed to hazardous volatile organic compounds. In this sensitive context, MANE opened its facilities to an intensive measuring campaign with the objective to better estimate the real level of hazardous respiratory exposure of workers. In this study, exposure to 27 hazardous volatile substances were measured during several types of handling operations (weighing-mixing, packaging, reconditioning-transferring), 430 measurement results were generated, and were exploited to propose an improved model derived from the well-known ECETOC-TRA model. The quantification of volatile substances in the working atmosphere involved three main steps: adsorption of the chemicals on a solid support, thermal desorption, followed by analysis by gas chromatography-mass spectrometry. Our approach was to examine experimental measures done in various manufacturing workplaces and to define correction factors to reflect more accurately working conditions and habits. Four correction factors were adjusted in the ECETOC-TRA to integrate important exposure variation factors: exposure duration, percentage of the substance in the composition, presence of collective protective equipment and wearing of personal protective equipment. Verification of the validity of the model is based on the comparison of the values obtained after adaptation of the ECETOC-TRA model, according to various exposure

  11. Respiratory Health – Exposure Measurements and Modeling in the Fragrance and Flavour Industry

    Science.gov (United States)

    Angelini, Eric; Camerini, Gerard; Diop, Malick; Roche, Patrice; Rodi, Thomas; Schippa, Christine; Thomas, Thierry

    2016-01-01

    Although the flavor and fragrance industry is about 150 years old, the use of synthetic materials started more than 100 years ago, and the awareness of the respiratory hazard presented by some flavoring substances emerged only recently. In 2001, the US National Institute of Occupational Safety and Health (NIOSH) identified for the first time inhalation exposure to flavoring substances in the workplace as a possible occupational hazard. As a consequence, manufacturers must comply with a variety of workplace safety requirements, and management has to ensure the improvement of health and safety of the employees exposed to hazardous volatile organic compounds. In this sensitive context, MANE opened its facilities to an intensive measuring campaign with the objective to better estimate the real level of hazardous respiratory exposure of workers. In this study, exposure to 27 hazardous volatile substances were measured during several types of handling operations (weighing-mixing, packaging, reconditioning-transferring), 430 measurement results were generated, and were exploited to propose an improved model derived from the well-known ECETOC-TRA model. The quantification of volatile substances in the working atmosphere involved three main steps: adsorption of the chemicals on a solid support, thermal desorption, followed by analysis by gas chromatography-mass spectrometry. Our approach was to examine experimental measures done in various manufacturing workplaces and to define correction factors to reflect more accurately working conditions and habits. Four correction factors were adjusted in the ECETOC-TRA to integrate important exposure variation factors: exposure duration, percentage of the substance in the composition, presence of collective protective equipment and wearing of personal protective equipment. Verification of the validity of the model is based on the comparison of the values obtained after adaptation of the ECETOC-TRA model, according to various exposure

  12. Respiratory Health - Exposure Measurements and Modeling in the Fragrance and Flavour Industry.

    Directory of Open Access Journals (Sweden)

    Eric Angelini

    Full Text Available Although the flavor and fragrance industry is about 150 years old, the use of synthetic materials started more than 100 years ago, and the awareness of the respiratory hazard presented by some flavoring substances emerged only recently. In 2001, the US National Institute of Occupational Safety and Health (NIOSH identified for the first time inhalation exposure to flavoring substances in the workplace as a possible occupational hazard. As a consequence, manufacturers must comply with a variety of workplace safety requirements, and management has to ensure the improvement of health and safety of the employees exposed to hazardous volatile organic compounds. In this sensitive context, MANE opened its facilities to an intensive measuring campaign with the objective to better estimate the real level of hazardous respiratory exposure of workers. In this study, exposure to 27 hazardous volatile substances were measured during several types of handling operations (weighing-mixing, packaging, reconditioning-transferring, 430 measurement results were generated, and were exploited to propose an improved model derived from the well-known ECETOC-TRA model. The quantification of volatile substances in the working atmosphere involved three main steps: adsorption of the chemicals on a solid support, thermal desorption, followed by analysis by gas chromatography-mass spectrometry. Our approach was to examine experimental measures done in various manufacturing workplaces and to define correction factors to reflect more accurately working conditions and habits. Four correction factors were adjusted in the ECETOC-TRA to integrate important exposure variation factors: exposure duration, percentage of the substance in the composition, presence of collective protective equipment and wearing of personal protective equipment. Verification of the validity of the model is based on the comparison of the values obtained after adaptation of the ECETOC-TRA model, according to

  13. Influence of Solvent-Solvent and Solute-Solvent Interaction Properties on Solvent-Mediated Potential

    International Nuclear Information System (INIS)

    Zhou Shiqi

    2005-01-01

    A recently proposed universal calculational recipe for solvent-mediated potential is applied to calculate excess potential of mean force between two large Lennard-Jones (LJ) or hard core attractive Yukawa particles immersed in small LJ solvent bath at supercritical state. Comparison between the present prediction with a hypernetted chain approximation adopted for solute-solute correlation at infinitely dilute limit and existing simulation data shows high accuracy for the region with large separation, and qualitative reliability for the solute particle contact region. The calculational simplicity of the present recipe allows for a detailed investigation on the effect of the solute-solvent and solvent-solvent interaction details on the excess potential of mean force. The resultant conclusion is that gathering of solvent particles near a solute particle leads to repulsive excess PMF, while depletion of solvent particles away from the solute particle leads to attractive excess PMF, and minor change of the solvent-solvent interaction range has large influence on the excess PMF.

  14. The primary exposure standard of ENEA for medium energy X-ray: characteristics and measurements procedures

    International Nuclear Information System (INIS)

    Laitano, R.F.; Toni, M.P.

    1983-01-01

    A description is given of a medium energy X-ray free-air chamber used, as primary exposure standard, at the Laboratorio di Metrologia delle Radiazioni Ionizzanti of the Enea in Italy. The main features of an X-ray facility for the production of radiation between 40 KeV and 400 KeV are also described. The measurements procedures are then analyzed with respect to the realization of the exposure unit in the relevant energy range. Finally the results of some international comparisons are reported

  15. Prenatal Triclosan Exposure and Anthropometric Measures Including Anogenital Distance in Danish Infants

    DEFF Research Database (Denmark)

    Lassen, Tina Harmer; Frederiksen, Hanne; Kyhl, Henriette Boye

    2016-01-01

    , Swan SH, Main KM, Andersson AM, Lind DV, Husby S, Wohlfahrt-Veje C, Skakkebæk NE, Jensen TK. 2016. Prenatal triclosan exposure and anthropometric measures including anogenital distance in Danish infants. Environ Health Perspect 124:1261-1268; http://dx.doi.org/10.1289/ehp.1409637.......BACKGROUND: Triclosan (TCS) is widely used as an antibacterial agent in consumer products such as hand soap and toothpaste, and human exposure is widespread. TCS is suspected of having endocrine-disrupting properties, but few human studies have examined the developmental effects of prenatal TCS...

  16. The Exposure Hierarchy as a Measure of Progress and Efficacy in the Treatment of Social Anxiety Disorder

    Science.gov (United States)

    Katerelos, Marina; Hawley, Lance L.; Antony, Martin M.; McCabe, Randi E.

    2008-01-01

    This study explored the psychometric properties and utility of the exposure hierarchy as a measure of treatment outcome for social anxiety disorder (SAD). An exposure hierarchy was created for each of 103 individuals with a diagnosis of SAD who completed a course of cognitive behavioral group therapy. Exposure hierarchy ratings were collected on a…

  17. CHILDREN'S RESIDENTIAL EXPOSURE TO CHLORPYRIFOS: APPLICATION OF CPPAES FIELD MEASUREMENTS OF CHLORPYRIFOS AND TCPY WITHIN MENTOR/SHEDS PESTICIDES MODEL

    Science.gov (United States)

    The comprehensive individual field-measurements on non-dietary exposure collected in the Children's-Post-Pesticide-Application-Exposure-Study (CPPAES) were used within MENTOR/SHEDS-Pesticides, a physically based stochastic human exposure and dose model. In this application, howev...

  18. Subjectively and objectively measured sleep with and without posttraumatic stress disorder and trauma exposure.

    Science.gov (United States)

    Kobayashi, Ihori; Huntley, Edward; Lavela, Joseph; Mellman, Thomas A

    2012-07-01

    Although reports of sleep disturbances are common among individuals with posttraumatic stress disorder (PTSD), results of polysomnographic (PSG) studies have inconsistently documented abnormalities and have therefore suggested "sleep state misperception." The authors' study objectives were to compare sleep parameters measured objectively and subjectively in the laboratory and at home in civilians with and without trauma exposure and PTSD. Cross-sectional study. PSG recordings in a sleep laboratory and actigraphic recordings in participants' homes. One hundred three urban-residing African Americans with and without trauma exposure and PTSD who participated in a larger study. N/A. Sleep parameters (total sleep time [TST], sleep onset latency [SOL], and wake after sleep onset [WASO]) were assessed using laboratory PSG and home actigraphy. A sleep diary was completed in the morning after PSG and actigraphy recordings. Habitual TST, SOL, and WASO were assessed using a sleep questionnaire. The Clinician Administered PTSD Scale was administered to assess participants' trauma exposure and PTSD diagnostic status. Participants, regardless of their trauma exposure/PTSD status, underestimated WASO in the diary and questionnaire relative to actigraphy and overestimated SOL in the diary relative to PSG. Among participants with current PTSD, TST diary estimates did not differ from the actigraphy measure in contrast with those without current PTSD who overestimated TST. No other significant group differences in discrepancies between subjective and objective sleep measures were found. Discrepancies between subjectively and objectively measured sleep parameters were not associated with trauma exposure or PTSD. This challenges prior assertions that individuals with PTSD overreport their sleep disturbances.

  19. Comparison of direct measurement methods for headset noise exposure in the workplace

    Directory of Open Access Journals (Sweden)

    Flora G Nassrallah

    2016-01-01

    Full Text Available The measurement of noise exposure from communication headsets poses a methodological challenge. Although several standards describe methods for general noise measurements in occupational settings, these are not directly applicable to noise assessments under communication headsets. For measurements under occluded ears, specialized methods have been specified by the International Standards Organization (ISO 11904 such as the microphone in a real ear and manikin techniques. Simpler methods have also been proposed in some national standards such as the use of general purpose artificial ears and simulators in conjunction with single number corrections to convert measurements to the equivalent diffuse field. However, little is known about the measurement agreement between these various methods and the acoustic manikin technique. Twelve experts positioned circum-aural, supra-aural and insert communication headsets on four different measurement setups (Type 1, Type 2, Type 3.3 artificial ears, and acoustic manikin. Fit-refit measurements of four audio communication signals were taken under quiet laboratory conditions. Data were transformed into equivalent diffuse-field sound levels using third-octave procedures. Results indicate that the Type 1 artificial ear is not suited for the measurement of sound exposure under communication headsets, while Type 2 and Type 3.3 artificial ears are in good agreement with the acoustic manikin technique. Single number corrections were found to introduce a large measurement uncertainty, making the use of the third-octave transformation preferable.

  20. Occupational exposure of phosphate mine workers: airborne radioactivity measurements and dose assessment

    International Nuclear Information System (INIS)

    Khater, Ashraf E.; Hussein, M.A.; Hussein, Mohamed I.

    2004-01-01

    Under the Egyptian program for radiation safety and control, airborne radioactivity measurements and radiological dose assessment were conducted in some phosphate and uranium mines. Abu-Tartor mine is one of the biggest underground phosphate mines in Egypt. Airborne radioactivity, radon ( 222 Rn) and its short-lived decay products (progenies) and thoron ( 220 Rn), were measured in selected locations along the mine. The environmental gamma and workers dose equivalent rate (mSv/y) were measured inside and outside the mine using thermo-luminescence dosimeters (TLD). The results were presented and discussed. The calculated annual effective dose due to airborne radioactivity is the main source of occupational exposure and exceeding the maximum recommended level by ICRP-60 inside the mine tunnels. A number of recommendations are suggested to control the occupational exposures

  1. Measurements of Solar Ultraviolet Radiation Exposure at Work and at Leisure in Danish Workers.

    Science.gov (United States)

    Grandahl, Kasper; Eriksen, Paul; Ibler, Kristina Sophie; Bonde, Jens Peter; Mortensen, Ole Steen

    2018-03-30

    Exposure to solar ultraviolet radiation is the main cause of skin cancer and may well present an occupational health and safety problem. In Denmark, skin cancer is a common disease in the general population, but detailed data on solar ultraviolet radiation exposure among outdoor workers are lacking. The aim of this study was to provide objective measurements of solar ultraviolet radiation exposure on working days and at leisure and compare levels of exposure between groups of mainly outdoor, equal-parts-outdoor-and-indoor and indoor workers. To this end, UV-B dosimeters with an aluminum gallium nitride (AlGaN) photodiode detector were used to measure the solar ultraviolet radiation exposure of 457 workers in the Danish summer season. Presented as semi-annual standard erythemal dose (SED) on working days, respectively, at leisure, the results are for mainly outdoor workers 214.2 SED and 64.8 SED, equal-parts-outdoor-and-indoor workers 131.4 SED and 64.8 SED, indoor workers 55.8 SED and 57.6 SED. The daily SED by month is significantly different (α = 0.05) between mainly outdoor, equal-parts-outdoor-and-indoor and indoor workers and across professional groups; some of which are exposed at very high levels that is roofers 361.8 SED. These findings substantiate that exposure to solar ultraviolet radiation is indeed an occupational health and safety problem in Denmark. © 2018 The Authors. Photochemistry and Photobiology published by Wiley Periodicals, Inc. on behalf of American Society for Photobiology.

  2. Measurement error in mobile source air pollution exposure estimates due to residential mobility during pregnancy.

    Science.gov (United States)

    Pennington, Audrey Flak; Strickland, Matthew J; Klein, Mitchel; Zhai, Xinxin; Russell, Armistead G; Hansen, Craig; Darrow, Lyndsey A

    2017-09-01

    Prenatal air pollution exposure is frequently estimated using maternal residential location at the time of delivery as a proxy for residence during pregnancy. We describe residential mobility during pregnancy among 19,951 children from the Kaiser Air Pollution and Pediatric Asthma Study, quantify measurement error in spatially resolved estimates of prenatal exposure to mobile source fine particulate matter (PM 2.5 ) due to ignoring this mobility, and simulate the impact of this error on estimates of epidemiologic associations. Two exposure estimates were compared, one calculated using complete residential histories during pregnancy (weighted average based on time spent at each address) and the second calculated using only residence at birth. Estimates were computed using annual averages of primary PM 2.5 from traffic emissions modeled using a Research LINE-source dispersion model for near-surface releases (RLINE) at 250 m resolution. In this cohort, 18.6% of children were born to mothers who moved at least once during pregnancy. Mobile source PM 2.5 exposure estimates calculated using complete residential histories during pregnancy and only residence at birth were highly correlated (r S >0.9). Simulations indicated that ignoring residential mobility resulted in modest bias of epidemiologic associations toward the null, but varied by maternal characteristics and prenatal exposure windows of interest (ranging from -2% to -10% bias).

  3. Online educative activities for solar ultraviolet radiation based on measurements of cloud amount and solar exposures.

    Science.gov (United States)

    Parisi, A V; Downs, N; Turner, J; Amar, A

    2016-09-01

    A set of online activities for children and the community that are based on an integrated real-time solar UV and cloud measurement system are described. These activities use the functionality of the internet to provide an educative tool for school children and the public on the influence of cloud and the angle of the sun above the horizon on the global erythemal UV or sunburning UV, the diffuse erythemal UV, the global UVA (320-400nm) and the vitamin D effective UV. Additionally, the units of UV exposure and UV irradiance are investigated, along with the meaning and calculation of the UV index (UVI). This research will help ensure that children and the general public are better informed about sun safety by improving their personal understanding of the daily and the atmospheric factors that influence solar UV radiation and the solar UV exposures of the various wavebands in the natural environment. The activities may correct common misconceptions of children and the public about UV irradiances and exposure, utilising the widespread reach of the internet to increase the public's awareness of the factors influencing UV irradiances and exposures in order to provide clear information for minimizing UV exposure, while maintaining healthy, outdoor lifestyles. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Performance of bias-correction methods for exposure measurement error using repeated measurements with and without missing data.

    Science.gov (United States)

    Batistatou, Evridiki; McNamee, Roseanne

    2012-12-10

    It is known that measurement error leads to bias in assessing exposure effects, which can however, be corrected if independent replicates are available. For expensive replicates, two-stage (2S) studies that produce data 'missing by design', may be preferred over a single-stage (1S) study, because in the second stage, measurement of replicates is restricted to a sample of first-stage subjects. Motivated by an occupational study on the acute effect of carbon black exposure on respiratory morbidity, we compare the performance of several bias-correction methods for both designs in a simulation study: an instrumental variable method (EVROS IV) based on grouping strategies, which had been recommended especially when measurement error is large, the regression calibration and the simulation extrapolation methods. For the 2S design, either the problem of 'missing' data was ignored or the 'missing' data were imputed using multiple imputations. Both in 1S and 2S designs, in the case of small or moderate measurement error, regression calibration was shown to be the preferred approach in terms of root mean square error. For 2S designs, regression calibration as implemented by Stata software is not recommended in contrast to our implementation of this method; the 'problematic' implementation of regression calibration although substantially improved with use of multiple imputations. The EVROS IV method, under a good/fairly good grouping, outperforms the regression calibration approach in both design scenarios when exposure mismeasurement is severe. Both in 1S and 2S designs with moderate or large measurement error, simulation extrapolation severely failed to correct for bias. Copyright © 2012 John Wiley & Sons, Ltd.

  5. Hazardous solvent substitution

    International Nuclear Information System (INIS)

    Twitchell, K.E.

    1995-01-01

    This article is an overview of efforts at INEL to reduce the generation of hazardous wastes through the elimination of hazardous solvents. To aid in their efforts, a number of databases have been developed and will become a part of an Integrated Solvent Substitution Data System. This latter data system will be accessible through Internet

  6. A novel dosimeter for measuring the amount of radiation exposure of surgeons during percutaneous nephrolithotomy: Instadose™

    Science.gov (United States)

    Yuruk, Emrah; Gureser, Gokhan; Tuken, Murat; Ertas, Kasim

    2016-01-01

    Introduction The aim of this study was to demonstrate the efficacy of Instadose™, a novel dosimeter designed for radiation workers to provide a measurement of the radiation dose at any time from any computer; to determine the amount of radiation exposure during percutaneous nephrolithotomy (PNL); and to evaluate the factors that affect the amount of radiation exposed. Material and methods Two experienced surgeons wore Instadose™ on the outer part of their lead aprons during the PNL procedures performed between December 2013 and July 2014. Patient demographics and stone characteristics were noted. Factors affecting radiation dose were determined. Fluoroscopic screening time was compared with the amount of radiation in order to validate the measurements of Instadose™. Results Overall, 51 patients with a mean age of 43.41 ±18.58 (range 1–75) years were enrolled. Male to female ratio was 35/16. The amount of radiation was greater than 0.01mSv in only 19 (37.25%) cases. Stone location complexity (p = 0.380), dilation type (p = 0.584), stone size (p = 0.565), dilation size (p = 0.891) and access number (p = 0.268) were not associated with increased radiation exposure. Instadose™ measurements were correlated with fluoroscopic screening time (r = 0.519, p = 0.001). Conclusions Instadose™ is a useful tool for the measurement of radiation exposure during PNL. The advantage of measuring the amount of radiation exposure after each PNL operation is that it may aid urologists in taking appropriate precautions to minimize the risk of radiation related complications. PMID:27551558

  7. High precision instrumentation for measuring the true exposure time in diagnostic X-ray examinations

    International Nuclear Information System (INIS)

    Silva, Danubia B.; Santos, Marcus A.P.; Barros, Fabio R.; Santos, Luiz A.P.

    2013-01-01

    One of the most important physical quantities to be evaluated in diagnostic radiology is the radiation exposure time experimented by the patient during the X-ray examination. IAEA and WHO organizations have suggested that any country must create a quality surveillance program to verify if each type of ionizing radiation equipment used in the hospitals and medical clinics are in conformity with the accepted uncertainties following the international standards. The purpose of this work is to present a new high precision methodology for measuring true exposure time in diagnostic X-ray examinations: pulsed, continuous or digital one. An electronic system named CronoX, which will be soon registered at the Brazilian Patent Office (INPI), is the equipment that provides such a high precision measurement. The principle of measurement is based on the electrical signal captured by a sensor that enters in a regeneration amplifier to transform it in a digital signal, which is treated by a microprocessor (uP). The signal treatment results in a two measured times: 1) T rx , the true X-ray exposure time; 2) T nx , the time in which the X-ray machine is repeatedly cut off during the pulsed irradiation and there is no delivery dose to the patient. Conventional Polymat X-ray equipment and dental X-ray machines were used to generate X-ray photons and take the measurements with the electronic systems. The results show that such a high precision instrumentation displays the true exposure time in diagnostic X-ray examinations and indicates a new method to be purposed for the quality surveillance programs in radiology. (author)

  8. Exposure rate measurements and radiation control in post therapy with I131

    International Nuclear Information System (INIS)

    Vazquez A, M.; Castillo D, C.; Flores U, H.; Cespedes C, L.; Morgan N, C.; Sifuentes D, Y.; Marin R, K.

    2015-10-01

    During hyperthyroidism treatment, 131 I activities from 111 MBq up to 296 MBq are used. In the aim to determine if the 131 I uptake by the patient is a radiological risk to family members and public around the patient exposure rate measurements were carried out, using a limit 1.8 m R/h. Measurements were carried out in the Nuclear Medicine department of Almenara hospital in Lima, Peru. The exposure rate was measured to 0.3, 0.6, and 1.0 m from the patient from 0 to 11 days after post-administrated dose (Pda). In this study measurements were carried out in 21 hyperthyroid patients. Measurements to 1 meter, along 2-4 (16/16), 5-7 (15/15), and 8-11 (14/14) days after Pda, indicate the dose rate around 100% of patients is ≤ 1.8 m R /h. Measurements to 0.6 meters along 2-4 (16/16), 5 -7 (15/15), and 8-11 (14/14) days after Pda, indicate that the dose rate around 44% (7/16), 93% (14/15), and 100% (14/14) of patients is ≤ 1.8 m R h. On the other hand, dose rate measurements to 0.3 meters, along 2-4 (16/16), 5-7 (15/15), and 8 -11 (14/14) days after Pda, indicate that de dose rate is 13% (2/16), 6% (1/15), and 43% (6/14) of patients is ≤ 1.8 m R/h. Measured exposure rates are alike to values reported in the literature, and were used to define radiation control recommendations. (Author)

  9. An Improved Apparatus for Vapour-Liquid Equilibria Measurement in Polymer + Solvent Systems at Higher Temperatures: a Study of the Water + Poly(ethylene glycol) System.

    Czech Academy of Sciences Publication Activity Database

    Pavlíček, Jan; Bogdanić, Grozdana; Wichterle, Ivan

    2017-01-01

    Roč. 454, 25 DEC (2017), s. 111-115 ISSN 0378-3812 R&D Projects: GA ČR GA15-19542S Institutional support: RVO:67985858 Keywords : correlation * experimental data * polymer-solvent system Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 2.473, year: 2016

  10. Seasonal variation in bioaerosol exposure during biowaste collection and measurements of leaked percolate

    DEFF Research Database (Denmark)

    Nielsen, Birgitte Herbert; Nielsen, Eva Møller; Breum, Niels O.

    2000-01-01

    The seasonal variation in waste collectors' exposure to microorganisms, endotoxin and dust was measured with personal sampling equipment. The measurement was carried out in three different combinations of storage and collection system for biowaste: container/compactor truck (CIC), paper sack....../compactor truck (P/C) and paper sack/platform truck (P/P). The maximum personal exposure was found to occur during the summer at the following median levels: total microorganisms 9.2 x 10(5) cells m(-3), culturable fungi (moulds) 7.8 x 10(4) cfu m(-3), Aspergillus fumigatus 2.9 x 10(-3) cfu m(3), mesophilic...... and endotoxin occurred in the CIC system (P trucks. Concentrations of endotoxin ranged from 3.9 to 6.1 x 10(5) EU ml(-1) (25 to 52 mu g ml(-1)) and the microflora of the percolate was dominated by bacteria (1...

  11. Radiation exposure of radiologists during angiography: Dose measurements outside the lead apron

    International Nuclear Information System (INIS)

    Fischer, H.; Przetak, C.; Teubert, G.; Ewen, K.; Moedder, U.

    1995-01-01

    The aim of this study was to provide practical information to angiographers concerning radiation exposure to body parts not covered by lead aprons. Individual doses to the neck and hands of radiologists measured in micro-Sieverts were obtained during the course of 80 angiographies of various types. The number of diagnostic and interventional procedures, which might lead to exceeding permissible doses, have been calculated. Possibilities of estimating doses during angiography by means of parameters such as screening times were examined statistically. Especially with regard to the hands, estimations of the doses are insufficient (correlation r=0.21). Radiologists who undertake much angiographic and particularly interventional work may reach exposure levels requiring protective measures in addition to lead aprons. (orig.) [de

  12. History of measures taken to reduce radiation exposure at Hamaoka Nuclear Power Station

    International Nuclear Information System (INIS)

    Kondou, Masashi; Takagi, Nobuyuki; Yabushita, Kazuo; Dekijima, Makoto

    2009-01-01

    Hamaoka Nuclear Power Station currently has five reactors, Units 1 to 5. Units 1 and 2 halted commercial operation in January 2009 and are now being prepared for decommissioning. Units 3 to 5 are operating at the rated thermal output with the gross electrical output of 3504 MWe. Hamaoka Nuclear Power Station has been operating for about 30 years since Unit 1 started up in 1976. Various measures have been taken to control water chemistry: for controlling SCC in the core internals and structural materials, hydrogen injection and noble metal injection were implemented; and to reduce radiation exposure for workers, condensate filter demineralizers were added, hollow fiber filters and pleated filters were installed in the condensate cleanup system, and zinc injection was performed. This paper describes measures taken at Hamaoka to reduce exposure in terms of water chemistry and techniques to monitor ion impurities in the reactor water. (author)

  13. Participatory measurements of individual exposure to air pollution in urban areas

    Science.gov (United States)

    Madelin, Malika; Duché, Sarah; Dupuis, Vincent

    2016-04-01

    Air pollution is a major environmental issue in urban areas. Chronic and high concentration exposure presents a health risk with cardiovascular and respiratory problems and longer term nervous, carcinogenic and endocrine problems. In addition to the estimations based on simulations of both background and regional pollution and of the pollution induced by the traffic, knowing exposure of each individual is a key issue. This exposure reflects the high variability of pollution at fine spatial and time scales, according to the proximity of emission sources and the urban morphology outside. The emergence of citizen science and the progress of miniaturized electronics, low-cost and accessible to (almost) everyone, offers new opportunities for the monitoring of air pollution, but also for the citizens' awareness of their individual exposure to air pollution. In this communication, we propose to present a participatory research project 'What is your air?' (project funded by the Île-de-France region), which aims at raising awareness on the theme of air quality, its monitoring with sensors assembled in a FabLab workshop and an online participatory mapping. Beyond the discussion on technical choices, the stages of manufacture or the sensor calibration procedures, we discuss the measurements made, in this case the fine particle concentration measurements, which are dated and georeferenced (communication via a mobile phone). They show high variability between the measurements (in part linked to the substrates, land use, traffic) and low daily contrasts. In addition to the analysis of the measurements and their comparison with the official data, we also discuss the choice of representation of information, including mapping, and therefore the message about pollution to communicate.

  14. 3D velocity measurements in fluid flows using multiple exposure holography

    International Nuclear Information System (INIS)

    Stanislas, M.; Rodriguez, O.; Dadi, M.; Beluche, F.

    1987-01-01

    An account is given of multiple exposure holography's application to the measurement of velocity in fluid flows. The method is nonintrusive, and yields access to the three components of the instantaneous velocity in three-dimensional domains. These characteristics render such holographic data complementary to classical LDV. Attention is given to solutions proposed for such limitations inherent in the method as the rather lengthy acquisition time; this difficulty is presently addressed by means of an automated evaluation methodology. 12 references

  15. A novel dosimeter for measuring the amount of radiation exposure of surgeons during percutaneous nephrolithotomy: Instadose?

    OpenAIRE

    Yuruk, Emrah; Gureser, Gokhan; Tuken, Murat; Ertas, Kasim; Serefoglu, Ege Can

    2016-01-01

    Introduction The aim of this study was to demonstrate the efficacy of Instadose?, a novel dosimeter designed for radiation workers to provide a measurement of the radiation dose at any time from any computer; to determine the amount of radiation exposure during percutaneous nephrolithotomy (PNL); and to evaluate the factors that affect the amount of radiation exposed. Material and methods Two experienced surgeons wore Instadose? on the outer part of their lead aprons during the PNL procedures...

  16. 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.

  17. 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

  18. 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

  19. Exposure rate measurements on TV monitors LiF:Mg, Cu, P (GR- 200A) chips

    International Nuclear Information System (INIS)

    Sanaye, S.S.; Sadagopan, Geetha; Bhatt, B.C.

    2004-01-01

    For measuring exposure rate on black and white TV monitor screen, LiF:Mg,Cu,P (GR-200A) TLD chips were used. The samples were kept on TV monitor screen and exposed for 560 hrs with TV in 'ON' condition. The exposure rate on TV monitor screen was determined from integrated TL measurements and it varied from 0.081μGy/hr to 0.106 μGy/hr. Thus it was observed that the exposure levels were well below the prescribed limits (i.e. 5 μGy/h at 5 cm from the surface). LiF:Mg,Cu,P (GR-200A) TLD discs were also used to estimate the dose level on the surface of two types of TV monitors. The samples were kept at five different locations on the two (14 C PT AND 20 C PT) models of TV monitors and exposed for 622 hrs. From the measurement of TL, integrated dose on the screen were in the range 3.86 mR to 12.34 mR, the corresponding dose rate being 6.206 mR/hr to 19.839 mR/hr. This ensures that doses were well below the recommended limit of 0.5 mR/hr at 5cm. (author)

  20. Estimating the acute health effects of coarse particulate matter accounting for exposure measurement error.

    Science.gov (United States)

    Chang, Howard H; Peng, Roger D; Dominici, Francesca

    2011-10-01

    In air pollution epidemiology, there is a growing interest in estimating the health effects of coarse particulate matter (PM) with aerodynamic diameter between 2.5 and 10 μm. Coarse PM concentrations can exhibit considerable spatial heterogeneity because the particles travel shorter distances and do not remain suspended in the atmosphere for an extended period of time. In this paper, we develop a modeling approach for estimating the short-term effects of air pollution in time series analysis when the ambient concentrations vary spatially within the study region. Specifically, our approach quantifies the error in the exposure variable by characterizing, on any given day, the disagreement in ambient concentrations measured across monitoring stations. This is accomplished by viewing monitor-level measurements as error-prone repeated measurements of the unobserved population average exposure. Inference is carried out in a Bayesian framework to fully account for uncertainty in the estimation of model parameters. Finally, by using different exposure indicators, we investigate the sensitivity of the association between coarse PM and daily hospital admissions based on a recent national multisite time series analysis. Among Medicare enrollees from 59 US counties between the period 1999 and 2005, we find a consistent positive association between coarse PM and same-day admission for cardiovascular diseases.

  1. Real-time measurement of dust in the workplace using video exposure monitoring: Farming to pharmaceuticals

    International Nuclear Information System (INIS)

    Walsh, P T; Forth, A R; Clark, R D R; Dowker, K P; Thorpe, A

    2009-01-01

    Real-time, photometric, portable dust monitors have been employed for video exposure monitoring (VEM) to measure and highlight dust levels generated by work activities, illustrate dust control techniques, and demonstrate good practice. Two workplaces, presenting different challenges for measurement, were used to illustrate the capabilities of VEM: (a) poultry farming activities and (b) powder transfer operations in a pharmaceutical company. For the poultry farm work, the real-time monitors were calibrated with respect to the respirable and inhalable dust concentrations using cyclone and IOM reference samplers respectively. Different rankings of exposure for typical activities were found on the small farm studied here compared to previous exposure measurements at larger poultry farms: these were mainly attributed to the different scales of operation. Large variations in the ratios of respirable, inhalable and real-time monitor TWA concentrations of poultry farm dust for various activities were found. This has implications for the calibration of light-scattering dust monitors with respect to inhalable dust concentration. In the pharmaceutical application, the effectiveness of a curtain barrier for dust control when dispensing powder in a downflow booth was rapidly demonstrated.

  2. Children’s Personal Exposure Measurements to Extremely Low Frequency Magnetic Fields in Italy

    Directory of Open Access Journals (Sweden)

    Ilaria Liorni

    2016-05-01

    Full Text Available Extremely low frequency magnetic fields (ELF-MFs exposure is still a topic of concern due to their possible impact on children’s health. Although epidemiological studies claimed an evidence of a possible association between ELF-MF above 0.4 μT and childhood leukemia, biological mechanisms able to support a causal relationship between ELF-MF and this disease were not found yet. To provide further knowledge about children’s ELF-MF exposure correlated to children’s daily activities, a measurement study was conducted in Milan (Italy. Eighty-six children were recruited, 52 of whom were specifically chosen with respect to the distance to power lines and built-in transformers to oversample potentially highly exposed children. Personal and bedroom measurements were performed for each child in two different seasons. The major outcomes of this study are: (1 median values over 24-h personal and bedroom measurements were <3 μT established by the Italian law as the quality target; (2 geometric mean values over 24-h bedroom measurements were mostly <0.4 μT; (3 seasonal variations did not significantly influence personal and bedroom measurements; (4 the highest average MF levels were mostly found at home during the day and outdoors; (5 no significant differences were found in the median and geometric mean values between personal and bedroom measurements, but were found in the arithmetic mean.

  3. Occupational exposure measurements of static and pulsed gradient magnetic fields in the vicinity of MRI scanners

    Energy Technology Data Exchange (ETDEWEB)

    Kaennaelae, Sami; Toivo, Tim; Jokela, Kari [STUK-Radiation and Nuclear Safety Authority, PO Box 14, 00881 Helsinki (Finland); Alanko, Tommi [Finnish Institute of Occupational Health, New Technologies and Risks, Topeliuksenkatu 41a A, 00250 Helsinki (Finland)], E-mail: sami.kannala@stuk.fi

    2009-04-07

    Recent advances in magnetic resonance imaging (MRI) have increased occupational exposure to magnetic fields. In this study, we examined the assessment of occupational exposure to gradient magnetic fields and time-varying magnetic fields generated by motion in non-homogeneous static magnetic fields of MRI scanners. These magnetic field components can be measured simultaneously with an induction coil setup that detects the time rate of change of magnetic flux density (dB/dt). The setup developed was used to measure the field components around two MRI units (1 T open and 3 T conventional). The measured values can be compared with dB/dt reference levels derived from magnetic flux density reference levels given by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The measured motion-induced dB/dt values were above the dB/dt reference levels for both MRI units. The measured values for the gradient fields (echo planar imaging (EPI) and fast field echo (FFE) sequences) also exceeded the dB/dt reference levels in positions where the medical staff may have access during interventional procedures. The highest motion-induced dB/dt values were 0.7 T s{sup -1} for the 1 T scanner and 3 T s{sup -1} for the 3 T scanner when only the static field was present. Even higher values (6.5 T s{sup -1}) were measured for simultaneous exposure to motion-induced and gradient fields in the vicinity of the 3 T scanner.

  4. Radon and radon-daughter exposure measurements by through-etched track registration in cellulose nitrate

    International Nuclear Information System (INIS)

    Knoefell, T.M.J.; Silva Estrada, J.J. da; Tavares, O.A.P.; Martins, J.B.

    1981-01-01

    The use of cellulose nitrate films LR-115 type II (Kodak-Pathe) as a practical, exposure integrating device to measure the level of exposure to alpha particles in atmospheres which contain radon and radon-daughter products is investigated. The analysis of a number of cellulose nitrate films that have been exposed to calibrated radon test-chamber atmospheres has indicated good correlations between through-etched track density p and integrated alpha-particle exposure Σa (Working-Level-Hour). It is shown that the response of the cellulose nitrate detector to radon-daughter alpha-particle exposures is linear, and that reliable conservative estimations of the Working-Level-Hour can be obtained from Σa = 3.0(p-b), where p is expressed in tracks/mm 2 (b is the background level). These results recommend the use of the special red cellulose nitrate films as a convenient dosimeter for monitoring radioactive contaminants in mine atmospheres. (Author) [pt

  5. An overview of measuring and modelling dose and risk from ionising radiation for medical exposures

    International Nuclear Information System (INIS)

    Tootell, Andrew; Szczepura, Katy; Hogg, Peter

    2014-01-01

    Purpose: This paper gives an overview of the methods that are used to calculate dose and risk from exposure to ionizing radiation as a support to other papers in this special issue. Background: The optimization of radiation dose is a legal requirement in medical exposures. This review paper aims to provide the reader with knowledge of dose by providing definitions and concepts of absorbed, effective and equivalent dose. Criticisms of the use of effective dose to infer the risk of an exposure to an individual will be discussed and an alternative approach considering the lifetime risks of cancer incidence will be considered. Prior to any dose or risk calculation, data concerning the dose absorbed by the patient needs to be collected. This paper will describe and discuss the main concepts and methods that can be utilised by a researcher in dose assessments. Concepts behind figures generated by imaging equipment such as dose-area-product, computed tomography dose index, dose length product and their use in effective dose calculations will be discussed. Processes, advantages and disadvantages in the simulation of exposures using the Monte Carlo method and direct measurement using digital dosimeters or thermoluminescent dosimeters will be considered. Beyond this special issue, it is proposed that this paper could serve as a teaching or CPD tool for personnel working or studying medical imaging

  6. Theoretical determination of spectrum-exposure rate conversion operator of HPGe detector and its application to the measurement of environmental gamma-ray exposure rate

    International Nuclear Information System (INIS)

    Park, Ch.M.; Choi, B.I.; Kwak, S.S.; Ji, P.K.; Kim, T.W.; Park, Y.W.; Yoon, B.K.

    1993-01-01

    A conversion operator between spectrum and exposure rate, using a portable HPGe detector for environmental radiation monitoring, was determined theoretically under the assumption of uniform distribution of radiation source on the ground surface. The measurement results were compared with those of a pressurized ionization chamber. The results obtained with the HPGe detector were slightly lower. The method can be easily applied to any gamma ray detector to obtain a spectrum - exposure-rate conversion factor for computing the exposure rate of environmental gamma radiation. (N.T.) 15 refs.; 6 figs.; 3 tabs

  7. Measuring the consequences of wildfires in a Bayesian network with vulnerability and exposure indicators

    Science.gov (United States)

    Papakosta, Panagiota; Botzler, Sebastian; Krug, Kai; Straub, Daniel

    2013-04-01

    Mediterranean climate type areas have always been experiencing fire events. However, population growth and expansion of urban centers into wildland areas during the 20th century (expansion of wildland-urban interface) has increased the threat to humans and their activities. Life and property losses, damage on infrastructure and crops, and forest degradation are some of the damages caused by wildfires. Although fires repeatedly occur along the Mediterranean basin, not all areas have experienced severe consequences. The extent of damage by wildfires is influenced by several factors, such as population density, vegetation type, topography, weather conditions and social preparedness [1]. Wildfire consequence estimation by means of vulnerability and exposure indicators is an essential part of wildfire risk analysis. Vulnerability indicators express the conditions that increase the susceptibility of a site to the impact of wildfires and exposure indicators describe the elements at risk [2],[3]. Appropriate indicators to measure wildfire vulnerability and exposure can vary with scale and site. The consequences can be classified into economic, social, environmental and safety, and they can be tangible (human life losses, buildings damaged) or intangible (damage of cultural heritage site). As a consequence, a variety of approaches exist and there is a lack of generalized unified easy-to-implement methodologies. In this study we present a methodology for measuring consequences of wildfires in a Mediterranean area in the mesoscale (1 km² spatial resolution). Vulnerability and exposure indicators covering all consequence levels are identified and their interrelations are stressed. Variables such as building materials, roofing type, and average building values are included in the economic vulnerability level. Safety exposure is expressed by population density, demographic structure, street density and distance to closest fire station. Environmental vulnerability of protected

  8. Upper arm elevation and repetitive shoulder movements: a general population job exposure matrix based on expert ratings and technical measurements.

    Science.gov (United States)

    Dalbøge, Annett; Hansson, Gert-Åke; Frost, Poul; Andersen, Johan Hviid; Heilskov-Hansen, Thomas; Svendsen, Susanne Wulff

    2016-08-01

    We recently constructed a general population job exposure matrix (JEM), The Shoulder JEM, based on expert ratings. The overall aim of this study was to convert expert-rated job exposures for upper arm elevation and repetitive shoulder movements to measurement scales. The Shoulder JEM covers all Danish occupational titles, divided into 172 job groups. For 36 of these job groups, we obtained technical measurements (inclinometry) of upper arm elevation and repetitive shoulder movements. To validate the expert-rated job exposures against the measured job exposures, we used Spearman rank correlations and the explained variance[Formula: see text] according to linear regression analyses (36 job groups). We used the linear regression equations to convert the expert-rated job exposures for all 172 job groups into predicted measured job exposures. Bland-Altman analyses were used to assess the agreement between the predicted and measured job exposures. The Spearman rank correlations were 0.63 for upper arm elevation and 0.64 for repetitive shoulder movements. The expert-rated job exposures explained 64% and 41% of the variance of the measured job exposures, respectively. The corresponding calibration equations were y=0.5%time+0.16×expert rating and y=27°/s+0.47×expert rating. The mean differences between predicted and measured job exposures were zero due to calibration; the 95% limits of agreement were ±2.9% time for upper arm elevation >90° and ±33°/s for repetitive shoulder movements. The updated Shoulder JEM can be used to present exposure-response relationships on measurement scales. 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/

  9. Surveillance indicators for potential reduced exposure products (PREPs): developing survey items to measure awareness

    Science.gov (United States)

    Bogen, Karen; Biener, Lois; Garrett, Catherine A; Allen, Jane; Cummings, K Michael; Hartman, Anne; Marcus, Stephen; McNeill, Ann; O'Connor, Richard J; Parascandola, Mark; Pederson, Linda

    2009-01-01

    Background Over the past decade, tobacco companies have introduced cigarettes and smokeless tobacco products (known as Potential Reduced Exposure Products, PREPs) with purportedly lower levels of some toxins than conventional cigarettes and smokeless products. It is essential that public health agencies monitor awareness, interest, use, and perceptions of these products so that their impact on population health can be detected at the earliest stages. Methods This paper reviews and critiques existing strategies for measuring awareness of PREPs from 16 published and unpublished studies. From these measures, we developed new surveillance items and subjected them to two rounds of cognitive testing, a common and accepted method for evaluating questionnaire wording. Results Our review suggests that high levels of awareness of PREPs reported in some studies are likely to be inaccurate. Two likely sources of inaccuracy in awareness measures were identified: 1) the tendency of respondents to misclassify "no additive" and "natural" cigarettes as PREPs and 2) the tendency of respondents to mistakenly report awareness as a result of confusion between PREPs brands and similarly named familiar products, for example, Eclipse chewing gum and Accord automobiles. Conclusion After evaluating new measures with cognitive interviews, we conclude that as of winter 2006, awareness of reduced exposure products among U.S. smokers was likely to be between 1% and 8%, with the higher estimates for some products occurring in test markets. Recommended measurement strategies for future surveys are presented. PMID:19840394

  10. Device for measuring the exposure time in dental X-ray - Cronox

    International Nuclear Information System (INIS)

    Menezes, Claudio J.M.; Santos, Luiz A.P. dos

    2009-01-01

    The Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE) developed a test device for monitoring the X-ray beam in dental equipment to its application in quality control programs. This device, called Odontologic Dosimetric Card (CDO of Cartao Dosimetrico Odontologico in Portuguese) uses thermoluminescent dosimeters (TLD) for the measurement of some parameters of the X-ray beam as the entrance surface dose, the peak tension and half value layer (HVL). Radiographic films record the size of the radiation field. However, the TLD does not allow the assessment of exposure time, a parameter that complements the requirements of the Diretrizes de Protecao Radiologica em Radiodiagnostico Medico e Odontologico of Department of Health in Brazil for such equipment. Thus was developed a system based on sensitivity to ionizing radiation of phototransistors for measurement of exposure time when a patient is put in a clinical dental radiography. The system, called CRONOX was sized to be inserted within the CDO. The results showed that the measuring error had developed for less than 3% when compared to reference values obtained with the Tektronix digital oscilloscope, TDS2022 model. The readings obtained with the CRONOX were also compared with the nominal values selected in the X-ray equipment and with the values measured with the instrument of trade PTW Diavolt Universal. The results showed that the measuring device developed showed a maximum deviation of 5.92% on the nominal value selected, while for the instrument of PTW was 17.86%. (author)

  11. Surveillance indicators for potential reduced exposure products (PREPs: developing survey items to measure awareness

    Directory of Open Access Journals (Sweden)

    McNeill Ann

    2009-10-01

    Full Text Available Abstract Background Over the past decade, tobacco companies have introduced cigarettes and smokeless tobacco products (known as Potential Reduced Exposure Products, PREPs with purportedly lower levels of some toxins than conventional cigarettes and smokeless products. It is essential that public health agencies monitor awareness, interest, use, and perceptions of these products so that their impact on population health can be detected at the earliest stages. Methods This paper reviews and critiques existing strategies for measuring awareness of PREPs from 16 published and unpublished studies. From these measures, we developed new surveillance items and subjected them to two rounds of cognitive testing, a common and accepted method for evaluating questionnaire wording. Results Our review suggests that high levels of awareness of PREPs reported in some studies are likely to be inaccurate. Two likely sources of inaccuracy in awareness measures were identified: 1 the tendency of respondents to misclassify "no additive" and "natural" cigarettes as PREPs and 2 the tendency of respondents to mistakenly report awareness as a result of confusion between PREPs brands and similarly named familiar products, for example, Eclipse chewing gum and Accord automobiles. Conclusion After evaluating new measures with cognitive interviews, we conclude that as of winter 2006, awareness of reduced exposure products among U.S. smokers was likely to be between 1% and 8%, with the higher estimates for some products occurring in test markets. Recommended measurement strategies for future surveys are presented.

  12. Exposure to electromagnetic fields from smart utility meters in GB; part I) laboratory measurements.

    Science.gov (United States)

    Peyman, Azadeh; Addison, Darren; Mee, Terry; Goiceanu, Cristian; Maslanyj, Myron; Mann, Simon

    2017-05-01

    Laboratory measurements of electric fields have been carried out around examples of smart meter devices used in Great Britain. The aim was to quantify exposure of people to radiofrequency signals emitted from smart meter devices operating at 2.4 GHz, and then to compare this with international (ICNIRP) health-related guidelines and with exposures from other telecommunication sources such as mobile phones and Wi-Fi devices. The angular distribution of the electric fields from a sample of 39 smart meter devices was measured in a controlled laboratory environment. The angular direction where the power density was greatest was identified and the equivalent isotropically radiated power was determined in the same direction. Finally, measurements were carried out as a function of distance at the angles where maximum field strengths were recorded around each device. The maximum equivalent power density measured during transmission around smart meter devices at 0.5 m and beyond was 15 mWm -2 , with an estimation of maximum duty factor of only 1%. One outlier device had a maximum power density of 91 mWm -2 . All power density measurements reported in this study were well below the 10 W m -2 ICNIRP reference level for the general public. Bioelectromagnetics. 2017;38:280-294. © 2017 Crown copyright. BIOELECTROMAGNETICS © 2017 Wiley Periodicals, Inc. © 2017 Crown copyright. BIOELECTROMAGNETICS © 2017 Wiley Periodicals, Inc.

  13. Structural transition of a homopolymer in solvents mixture

    Energy Technology Data Exchange (ETDEWEB)

    Guettari, Moez [Laboratoire de Physique de la Matiere Molle, Faculte des Sciences de Tunis, Campus Universitaire, 2092 Tunisia (Tunisia)], E-mail: gtarimoez@yahoo.fr; Aschi, Adel; Gomati, Riadh; Gharbi, Abdelhafidh [Laboratoire de Physique de la Matiere Molle, Faculte des Sciences de Tunis, Campus Universitaire, 2092 Tunisia (Tunisia)

    2008-07-01

    The present work is aimed at studying the thermodynamic behaviour of a polymer in solvents mixture. Dynamic light scattering is used to measure the hydrodynamic radius of polyvinylpyrrolidone (M{sub w} = 360,000 g/mol), in water/methanol solvents mixture, versus the mixed solvents composition at 25 deg. C. Then, we show that the polymer conformation adopts the Coil-Globule-Coil structure when the methanol molar fraction X{sub A} is varied. This transition is attributed to solvent quality change which result from water and methanol complex formation. The polymer contraction rate calculated for each composition takes its maximum value at X{sub A} = 0.17. Hildebrand theory assuming the solvents mixture as an equivalent solvent was used to analyze the change in mixed solvents quality. These changes can be attributed to dispersive forces in solvents mixture.

  14. Structural transition of a homopolymer in solvents mixture

    International Nuclear Information System (INIS)

    Guettari, Moez; Aschi, Adel; Gomati, Riadh; Gharbi, Abdelhafidh

    2008-01-01

    The present work is aimed at studying the thermodynamic behaviour of a polymer in solvents mixture. Dynamic light scattering is used to measure the hydrodynamic radius of polyvinylpyrrolidone (M w = 360,000 g/mol), in water/methanol solvents mixture, versus the mixed solvents composition at 25 deg. C. Then, we show that the polymer conformation adopts the Coil-Globule-Coil structure when the methanol molar fraction X A is varied. This transition is attributed to solvent quality change which result from water and methanol complex formation. The polymer contraction rate calculated for each composition takes its maximum value at X A = 0.17. Hildebrand theory assuming the solvents mixture as an equivalent solvent was used to analyze the change in mixed solvents quality. These changes can be attributed to dispersive forces in solvents mixture

  15. Radiation measurements in Egyptian pyramids and tombs -- occupational exposure of workers and the public

    Energy Technology Data Exchange (ETDEWEB)

    Bigu, J; Hussein, Mohamed I; Hussein, A Z

    2000-02-01

    A radiation survey of seven archaeological sites within Egyptian pyramids and tombs has been conducted in the Saggara area. Measurements were made of radon ({sup 222}Rn) and its short-lived decay products (progeny), as well as thoron ({sup 220}Rn) progeny and {gamma}-radiation. The results of these measurements have been used to calculate the maximum annual effective dose (MAD) and other important occupational radiation exposure variables. It was found that for the limited time to which occupational workers and visitors were exposed, their respective MAD values were lower than that recommended by the regulatory agency (i.e., 20 mSv per year for occupational workers and 1 mSv in a year for the public). However, it is shown that if the exposure times for occupational workers were to increase to 'normal' working schedules their MAD would be exceeded at three archaeological sites. Implementation of improved ventilation practices is recommended in those sites to reduce the exposure to occupational workers were their working schedules to be significantly increased. It is also recommended that further monitoring be conducted in the future to verify these results.

  16. Radiation measurements in Egyptian pyramids and tombs -- occupational exposure of workers and the public

    International Nuclear Information System (INIS)

    Bigu, J.; Hussein, Mohamed I.; Hussein, A.Z.

    2000-01-01

    A radiation survey of seven archaeological sites within Egyptian pyramids and tombs has been conducted in the Saggara area. Measurements were made of radon ( 222 Rn) and its short-lived decay products (progeny), as well as thoron ( 220 Rn) progeny and γ-radiation. The results of these measurements have been used to calculate the maximum annual effective dose (MAD) and other important occupational radiation exposure variables. It was found that for the limited time to which occupational workers and visitors were exposed, their respective MAD values were lower than that recommended by the regulatory agency (i.e., 20 mSv per year for occupational workers and 1 mSv in a year for the public). However, it is shown that if the exposure times for occupational workers were to increase to 'normal' working schedules their MAD would be exceeded at three archaeological sites. Implementation of improved ventilation practices is recommended in those sites to reduce the exposure to occupational workers were their working schedules to be significantly increased. It is also recommended that further monitoring be conducted in the future to verify these results

  17. A national prediction model for PM2.5 component exposures and measurement error-corrected health effect inference.

    Science.gov (United States)

    Bergen, Silas; Sheppard, Lianne; Sampson, Paul D; Kim, Sun-Young; Richards, Mark; Vedal, Sverre; Kaufman, Joel D; Szpiro, Adam A

    2013-09-01

    Studies estimating health effects of long-term air pollution exposure often use a two-stage approach: building exposure models to assign individual-level exposures, which are then used in regression analyses. This requires accurate exposure modeling and careful treatment of exposure measurement error. To illustrate the importance of accounting for exposure model characteristics in two-stage air pollution studies, we considered a case study based on data from the Multi-Ethnic Study of Atherosclerosis (MESA). We built national spatial exposure models that used partial least squares and universal kriging to estimate annual average concentrations of four PM2.5 components: elemental carbon (EC), organic carbon (OC), silicon (Si), and sulfur (S). We predicted PM2.5 component exposures for the MESA cohort and estimated cross-sectional associations with carotid intima-media thickness (CIMT), adjusting for subject-specific covariates. We corrected for measurement error using recently developed methods that account for the spatial structure of predicted exposures. Our models performed well, with cross-validated R2 values ranging from 0.62 to 0.95. Naïve analyses that did not account for measurement error indicated statistically significant associations between CIMT and exposure to OC, Si, and S. EC and OC exhibited little spatial correlation, and the corrected inference was unchanged from the naïve analysis. The Si and S exposure surfaces displayed notable spatial correlation, resulting in corrected confidence intervals (CIs) that were 50% wider than the naïve CIs, but that were still statistically significant. The impact of correcting for measurement error on health effect inference is concordant with the degree of spatial correlation in the exposure surfaces. Exposure model characteristics must be considered when performing two-stage air pollution epidemiologic analyses because naïve health effect inference may be inappropriate.

  18. Measurement and correlation of solubility of thiourea in two solvent mixtures from T = (283.15 to 313.15) K

    International Nuclear Information System (INIS)

    Wang, Yanmeng; Yin, Qiuxiang; Sun, Xiaowei; Bao, Ying; Gong, Junbo; Hou, Baohong; Wang, Yongli; Zhang, Meijing; Xie, Chuang; Hao, Hongxun

    2016-01-01

    Highlights: • Solubility of thiourea in methanol + ethanol and methanol + propanol was studied. • Experimental and calculated (NIBS/R-K) data are in a good agreement. • Interaction between solute and solvent are calculated by Molecular simulation. • Thermodynamic properties of both dissolving and mixing process are calculated. - Abstract: The solubility data of thiourea in methanol + ethanol mixtures and methanol + n-propanol mixtures were determined from T = (283.15 to 313.15) K by gravimetric method under atmospheric pressure. Effects of solvent composition and temperature on solubility of thiourea were discussed. Molecular simulation results indicate that solubility of thiourea will be influenced by interaction energy and a quantitative conclusion can be drawn from the modeling result. To extend the applicability of the solubility data, experimental solubility data in two kinds of binary solvent mixtures were correlated by the modified Apelblat equation, λ–h equation and (NIBS)/Redlich–Kister model. It was found that all the three models could satisfactorily correlate the experimental data and the (NIBS)/Redlich–Kister model could give better correlation results. Furthermore, thermodynamic properties of dissolving and mixing process of thiourea, including the enthalpy, the Gibbs energy and the entropy, were also calculated and analyzed.

  19. An introduction to the indirect exposure assessment approach: modeling human exposure using microenvironmental measurements and the recent National Human Activity Pattern Survey.

    Science.gov (United States)

    Klepeis, N E

    1999-01-01

    Indirect exposure approaches offer a feasible and accurate method for estimating population exposures to indoor pollutants, including environmental tobacco smoke (ETS). In an effort to make the indirect exposure assessment approach more accessible to people in the health and risk assessment fields, this paper provides examples using real data from (italic>a(/italic>) a week-long personal carbon monoxide monitoring survey conducted by the author; and (italic>b(/italic>) the 1992 to 1994 National Human Activity Pattern Survey (NHAPS) for the United States. The indirect approach uses measurements of exposures in specific microenvironments (e.g., homes, bars, offices), validated microenvironmental models (based on the mass balance equation), and human activity pattern data obtained from questionnaires to predict frequency distributions of exposure for entire populations. This approach requires fewer resources than the direct approach to exposure assessment, for which the distribution of monitors to a representative sample of a given population is necessary. In the indirect exposure assessment approach, average microenvironmental concentrations are multiplied by the total time spent in each microenvironment to give total integrated exposure. By assuming that the concentrations encountered in each of 10 location categories are the same for different members of the U.S. population (i.e., the NHAPS respondents), the hypothetical contribution that ETS makes to the average 24-hr respirable suspended particle exposure for Americans working their main job is calculated in this paper to be 18 microg/m3. This article is an illustrative review and does not contain an actual exposure assessment or model validation. Images Figure 3 Figure 4 PMID:10350522

  20. Solvent - solute interaction

    International Nuclear Information System (INIS)

    Urbanczyk, A.; Kalinowski, M.K.

    1983-01-01

    The electronic absorption spectrum of vanadyl acetylacetonate has been studied in 15 organic solvents. It has been found that wavenumbers and molar absorptivities of the long-wavelength bands (d-d transitions) can be well described by a complementary Lewis acid-base model including Gutmann's donor number [Gutmann V., Wychera E., Inorg. Nucl. Chem. Letters 2, 257 (1966)] and acceptor number [Mayer U., Gutmann V., Gerger W., Monatsh. Chem. 106, 1235 (1975)] of a solvent. This model describes also the solvent effect of the hyperfine splitting constant, Asub(iso)( 51 V), from e.s.r. spectra of VOacac 2 . These observations are discussed in terms of the donor-acceptor concept for solvent-solute interactions. (Author)

  1. Measuring youth exposure to alcohol marketing on social networking sites: challenges and prospects.

    Science.gov (United States)

    Jernigan, David H; Rushman, Anne E

    2014-02-01

    Youth exposure to alcohol marketing has been linked to increased alcohol consumption and problems. On relatively new and highly interactive social networking sites (SNS) that are popular with youth, tools for measuring youth exposure to alcohol marketing in traditional media are inadequate. We critically review the existing policies of Facebook, Twitter, and YouTube designed to keep branded alcohol content away from underage youth. Looking at brand and user activity on Facebook for the 15 alcohol brands most popular among US youth, we found activity has grown dramatically in the past 3 years, and underage users may be accounting for some of this activity. Surveys of youth and adult participation in alcohol marketing on SNS will be needed to inform debate over these marketing practices.

  2. Nickel concentrations in fingernails as a measure of occupational exposure to nickel

    DEFF Research Database (Denmark)

    Peters, K; Gammelgaard, Bente; Menné, T

    1991-01-01

    in nails (p less than 0.001). The difference between the 2 levels was also significant (p less than 0.001). No correlation between the nickel concentration in fingernails and the duration of exposure could be demonstrated. It was concluded that the higher the nickel level in the fingernails, the greater...... is the possibility that the person is occupationally exposed to nickel. Nail analysis is suggested as a measure of occupational exposure to nickel.......The nickel concentration in fingernails from 2 groups of people occupationally exposed to nickel was determined. In one group, comprising 83 persons moderately exposed to nickel, the mean +/- standard deviation (SD) was 29.2 micrograms/g +/- 56.7 micrograms/g and the median 13.8 micrograms/g (range...

  3. An Industrial Radipgraphy Exposure Device Based on Measurement of Transmitted Gamma-Ray Intensity

    International Nuclear Information System (INIS)

    Polee, C.; Chankow, N.; Srisatit, S.; Thong-Aram, D.

    2014-01-01

    In film radiography, underexposure and overexposure may happen particularly when lacking knowledge of specimen material and hollowness. This paper describes a method and a device for determining exposure in industrial gamma-ray radiography based on quick measurement of transmitted gamma-ray intensity with a D3372 Hamamatsu small GM tube. Application software is developed for Android mobile phone to remotely control the device and to display the counting data via Bluetooth. Prior to placing film, the device is placed behind the specimen to be radiographed to determine the exposure time from the transmitted intensity which is independent on source activity, source-to-film distance, specimen thickness and kind of material. The developed technique and device make radiographic process economic, convenient and more reliable.

  4. Carpet-dust chemicals as measures of exposure: Implications of variability

    Directory of Open Access Journals (Sweden)

    Whitehead Todd P

    2012-03-01

    Full Text Available Abstract Background There is increasing interest in using chemicals measured in carpet dust as indicators of chemical exposures. However, investigators have rarely sampled dust repeatedly from the same households and therefore little is known about the variability of chemical levels that exist within and between households in dust samples. Results We analyzed 9 polycyclic aromatic hydrocarbons, 6 polychlorinated biphenyls, and nicotine in 68 carpet-dust samples from 21 households in agricultural communities of Fresno County, California collected from 2003-2005. Chemical concentrations (ng per g dust ranged from Conclusions Our findings suggest that attenuation bias should be relatively modest when using these semi-volatile carpet-dust chemicals as exposure surrogates in epidemiologic studies.

  5. Neuropsychological performance in solvent-exposed vehicle collision repair workers in New Zealand

    OpenAIRE

    Keer, Samuel; Glass, Bill; McLean, Dave; Harding, Elizabeth; Babbage, Duncan; Leathem, Janet; Brinkmann, Yanis; Prezant, Bradley; Pearce, Neil; Douwes, Jeroen

    2017-01-01

    Objectives To assess whether contemporary solvent exposures in the vehicle collision repair industry are associated with objectively measured neuropsychological performance in collision repair workers. Methods The RBANS battery and additional tests were administered to 47 vehicle collision repair and 51 comparison workers randomly selected from a previous questionnaire study. Results Collision repair workers performed lower on tests of attention (digit span backwards: -1.5, 95% CI -2.4, -0.5;...

  6. Caustic-Side Solvent Extraction: Chemical and Physical Properties of the Optimized Solvent

    Energy Technology Data Exchange (ETDEWEB)

    Delmau, L.H.

    2002-10-08

    This work was undertaken to optimize the solvent used in the Caustic Side Solvent Extraction (CSSX) process and to measure key chemical and physical properties related to its performance in the removal of cesium from the alkaline high-level salt waste stored in tanks at the Savannah River Site. The need to adjust the solvent composition arose from the prior discovery that the previous baseline solvent was supersaturated with respect to the calixarene extractant. The following solvent-component concentrations in Isopar{reg_sign} L diluent are recommended: 0.007 M calix[4]arene-bis(tert-octylbenzo-crown-6) (BOBCalixC6) extractant, 0.75 M 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) phase modifier, and 0.003 M tri-n-octylamine (TOA) stripping aid. Criteria for this selection included BOBCalixC6 solubility, batch cesium distribution ratios (D{sub Cs}), calculated flowsheet robustness, third-phase formation, coalescence rate (dispersion numbers), and solvent density. Although minor compromises within acceptable limits were made in flowsheet robustness and solvent density, significant benefits were gained in lower risk of third-phase formation and lower solvent cost. Data are also reported for the optimized solvent regarding the temperature dependence of D{sub Cs} in extraction, scrubbing, and stripping (ESS); ESS performance on recycle; partitioning of BOBCalixC6, Cs-7SB, and TOA to aqueous process solutions; partitioning of organic anions; distribution of metals; solvent phase separation at low temperatures; solvent stability to elevated temperatures; and solvent density and viscosity. Overall, the technical risk of the CSSX process has been reduced by resolving previously identified issues and raising no new issues.

  7. Measurement of radioactive aerosol behavior during dismantling and reflection to the exposure dose evaluation - 16107

    International Nuclear Information System (INIS)

    Iguchi, Yukihiro; Kato, Masami

    2009-01-01

    Radioactive aerosol disperses slightly via contamination prevention systems such as control enclosures and filters when the nuclear installation is dismantled, and it might impact the environment. Therefore, when decommissioning is planned, it is necessary to assess the safety such as exposure dose evaluation to the public. For the radioactive aerosol, it is possible that the dispersion ratio is different according to the contamination condition, the dismantlement method of the material, nuclides (elements), etc. The radiation exposure evaluation for the decommissioning plan has been executed by operators in Japan based on a number of experiments (mostly cold tests) and overseas results. The decommissioning is now being carried out at the Tokai Power Station (GCR) and Fugen Decommissioning Engineering Center in Japan. In this study, the results data is acquired at the decommissioning sites, and the methodology and data for the exposure dose evaluation are verified and confirmed. These examination results will lead to the upgrading and improvement of the exposure evaluation methodology. In particular, the dismantlement work of connected piping of the heat exchanger (steam generator) was executed in the Tokai Power Station in 2008. In this study, we paid attention to the radionuclides of Co-60 and Cs-137 that adhered to piping, and the dispersion behavior of aerosol was measured and contamination prevention effect was assured. As a result, the data show that the cesium concentrates about four times higher than cobalt. Moreover, the effects of the prevention measures of contamination were confirmed and the behavior of the radioactive aerosol became clear and the effective findings about the dose evaluation of the dismantling were collected. (authors)

  8. Assessment of human body influence on exposure measurements of electric field in indoor enclosures.

    Science.gov (United States)

    de Miguel-Bilbao, Silvia; García, Jorge; Ramos, Victoria; Blas, Juan

    2015-02-01

    Personal exposure meters (PEMs) used for measuring exposure to electromagnetic fields (EMF) are typically used in epidemiological studies. As is well known, these measurement devices cause a perturbation of real EMF exposure levels due to the presence of the human body in the immediate proximity. This paper aims to model the alteration caused by the body shadow effect (BSE) in motion conditions and in indoor enclosures at the Wi-Fi frequency of 2.4 GHz. For this purpose, simulation techniques based on ray-tracing have been carried out, and their results have been verified experimentally. A good agreement exists between simulation and experimental results in terms of electric field (E-field) levels, and taking into account the cumulative distribution function (CDF) of the spatial distribution of amplitude. The Kolmogorov-Smirnov (KS) test provides a P-value greater than 0.05, in fact close to 1. It has been found that the influence of the presence of the human body can be characterized as an angle of shadow that depends on the dimensions of the indoor enclosure. The CDFs show that the E-field levels in indoor conditions follow a lognormal distribution in the absence of the human body and under the influence of BSE. In conclusion, the perturbation caused by BSE in PEMs readings cannot be compensated for by correction factors. Although the mean value is well adjusted, BSE causes changes in CDF that would require improvements in measurement protocols and in the design of measuring devices to subsequently avoid systematic errors. © 2014 Wiley Periodicals, Inc.

  9. Work ability score of solvent-exposed workers.

    Science.gov (United States)

    Furu, Heidi; Sainio, Markku; Hyvärinen, Hanna-Kaisa; Kaukiainen, Ari

    2018-03-28

    Occupational chronic solvent encephalopathy (CSE), characterized by neurocognitive dysfunction, often leads to early retirement. However, only the more severe cases are diagnosed with CSE, and little is known about the work ability of solvent-exposed workers in general. The aim was to study memory and concentration symptoms, work ability and the effect of both solvent-related and non-occupational factors on work ability, in an actively working solvent-exposed population. A questionnaire on exposure and health was sent to 3640 workers in four solvent-exposed fields, i.e. painters and floor-layers, boat builders, printers, and metal workers. The total number of responses was 1730. We determined the work ability score (WAS), a single question item of the Work Ability Index, and studied solvent exposure, demographic factors, Euroquest memory and concentration symptoms, chronic diseases, and employment status using univariate and multivariate analyses. The findings were compared to those of a corresponding national blue-collar reference population (n = 221), and a small cohort of workers with CSE (n = 18). The proportion of workers with memory and concentration symptoms was significantly associated with solvent exposure. The WAS of solvent-exposed workers was lower than that of the national blue-collar reference group, and the difference was significant in the oldest age group (those aged over 60). Solvent-exposed worker's WAS were higher than those of workers diagnosed with CSE. The WAS were lowest among painters and floor-layers, followed by metal workers and printers, and highest among boat builders. The strongest explanatory factors for poor work ability were the number of chronic diseases, age and employment status. Solvent exposure was a weak independent risk factor for reduced WAS, comparable to a level of high alcohol consumption. Even if memory and concentration symptoms were associated with higher solvent exposure, the effect of solvents on self

  10. Bias and power in group-based epidemiologic studies of low-back pain exposure and outcome--effects of study size and exposure measurement efforts.

    Science.gov (United States)

    Coenen, Pieter; Mathiassen, Svend Erik; Kingma, Idsart; Boot, Cécile R L; Bongers, Paulien M; van Dieën, Jaap H

    2015-05-01

    Exposure-outcome studies, for instance on work-related low-back pain (LBP), often classify workers into groups for which exposures are estimated from measurements on a sample of workers within or outside the specific study. The present study investigated the influence on bias and power in exposure-outcome associations of the sizes of the total study population and the sample used to estimate exposures. At baseline, lifting, trunk flexion, and trunk rotation were observed for 371 of 1131 workers allocated to 19 a-priori defined occupational groups. LBP (dichotomous) was reported by all workers during 3 years of follow-up. All three exposures were associated with LBP in this parent study (P power (P power >0.80 (P level = 0.05). A similar performance required n ≥ 30 workers for rotated trunk. Small numbers of observed workers (k) resulted in biased OR, while power was, in general, more sensitive to the total number of workers (n). In epidemiologic studies using a group-based exposure assessment strategy, statistical performance may be sufficient if outcome is obtained from a reasonably large number of workers, even if exposure is estimated from only few workers per group. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  11. VALIDITATION OF A LIGHT QUESTIONNAIRE WITH REAL-LIFE PHOTOPIC ILLUMINANCE MEASUREMENTS: THE HARVARD LIGHT EXPOSURE ASSESSMENT QUESTIONNAIRE

    Science.gov (United States)

    Bajaj, Archna; Rosner, Bernard; Lockley, Steven; Schernhammer, Eva S.

    2011-01-01

    Background Light exposure at night is now considered a probable carcinogen. To study the effects of light on chronic diseases like cancer, methods to measure light exposure in large observational studies are needed. We aimed to investigate the validity of self-reported current light exposure. Methods We developed a self-administered semiquantitative light questionnaire, the Harvard Light Exposure Assessment (H-LEA) questionnaire, and compared photopic scores derived from this questionnaire with actual photopic and circadian measures obtained from a real-life 7-day light meter application among 132 women (85 rotating night shift workers and 47 day workers) participating in the Nurses' Health Study II. Results After adjustment for age, BMI, collection day, and night work status, the overall partial Spearman correlation between self-report of light exposure and actual photopic light measurements was 0.72 (P<0.001; Kendall τ =0.57) and 0.73 (P<0.0001; Kendall τ =0.58) when correlating circadian light measurements. There were only minimal differences in accuracy of self-report of light exposure and photopic or circadian light measurement between day (r=0.77 and 0.78, respectively) and rotating night shift workers (r=0.68 and 0.69, respectively). Conclusions The results of this study provide evidence of the criterion validity of self-reported light exposure using the H-LEA questionnaire. Impact: This questionnaire is a practical method of assessing light exposure in large scale epidemiologic studies. PMID:21737411

  12. Measurement of neutron radiation exposure of commercial airline pilots using bubble detectors

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, B.J.; Kosierb, R. (Royal Military College of Canada, Kingston, Ontario (Canada). Dept. of Chemistry and Chemical Engineering); Cousins, T. (Defense Research Establishment Ottawa, Ontario (Canada). Space Systems and Technology Section); Hudson, D.F. (Air Canada Flight Operations, Vancouver, British Columbia (Canada)); Guery, G. (Air France-Direction des Operations Aeriennes, Roissy Charles de Gaulle (France))

    1994-06-01

    Neutron bubble detectors have been used over a 1-yr period by commercial airline pilots from Air Canada and Air France to measure the high-altitude neutron radiation exposure produced by galactic cosmic rays. The present work yielded measurements of the neutron flux of 1.0 to 4.6 n/cm[sup 2][center dot]s, and the neutron dose equivalent rates of 1.7 to 7.7 [mu]S[nu]/h. These measurements are in agreement with previous studies using high-altitude aircraft and conventional neutron instrumentation. The total dose equivalents for the Air Canada flights are also consistent with predictions of the CARI code. Considering that the neutron component contributes [approximately] 50% of the total dose equivalent, this study indicates that the annual dose for the air crew member would exceed the new recommendations of the International Commission on Radiological Protection (ICRP-60) for the general public.

  13. Measurement of neutron radiation exposure of commercial airline pilots using bubble detectors

    International Nuclear Information System (INIS)

    Lewis, B.J.; Kosierb, R.; Guery, G.

    1994-01-01

    Neutron bubble detectors have been used over a 1-yr period by commercial airline pilots from Air Canada and Air France to measure the high-altitude neutron radiation exposure produced by galactic cosmic rays. The present work yielded measurements of the neutron flux of 1.0 to 4.6 n/cm 2 ·s, and the neutron dose equivalent rates of 1.7 to 7.7 μSν/h. These measurements are in agreement with previous studies using high-altitude aircraft and conventional neutron instrumentation. The total dose equivalents for the Air Canada flights are also consistent with predictions of the CARI code. Considering that the neutron component contributes ∼ 50% of the total dose equivalent, this study indicates that the annual dose for the air crew member would exceed the new recommendations of the International Commission on Radiological Protection (ICRP-60) for the general public

  14. Evaluation of external exposures of the population of Ozyorsk, Russia, with luminescence measurements of bricks.

    Science.gov (United States)

    Woda, Clemens; Jacob, P; Ulanovsky, A; Fiedler, I; Mokrov, Y; Rovny, S

    2009-11-01

    Recently discovered historical documents indicate that large releases of noble gases (mainly (41)Ar and radioactive isotopes of Kr and Xe) from the Mayak Production Association (MPA) over the period from 1948 to 1956 may have caused considerable external exposures of both, inhabitants of Ozyorsk and former inhabitants of villages at the upper Techa River. To quantify this exposure, seven brick samples from three buildings in Ozyorsk, located 8-10 km north-northwest from the radioactive gas release points, were taken. The absorbed dose in brick was measured in a depth interval of 3-13 mm below the exposed surface of the bricks by means of the thermoluminescence (TL) and the optically stimulated luminescence (OSL) method. Generally, luminescence properties using TL were more favorable for precise dose determination than using OSL, but within their uncertainties the results from both methods agree well with each other. The absorbed dose due to natural radiation was assessed and subtracted under the assumption of the bricks to be completely dry. The weighted average of the anthropogenic dose for all samples measured by TL and OSL is 10 +/- 9 and 1 +/- 9 mGy, respectively. An upper limit for a possible anthropogenic dose in brick that would not be detected due to the measurement uncertainties is estimated at 24 mGy. This corresponds to an effective dose of about 21 mSv. A similar range of values is obtained in recently published dispersion calculations that were based on reconstructed MPA releases. It is concluded that the release of radioactive noble gases from the radiochemical and reactor plants at Mayak PA did not lead to a significant external exposure of the population of Ozyorsk. In addition, the study demonstrates the detection limit for anthropogenic doses in ca. 60-year-old bricks to be about 24 mGy, if luminescence methods are used.

  15. Measurements of radiation exposure of dentistry students during their radiological training using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Loya, M.; Sanín, L.H.; González, P.R.; Ávila, O.; Duarte, R.; Ojeda, S.L.; Montero-Cabrera, M.E.

    2016-01-01

    Exposure among dentistry students has not been assessed or regulated in Mexico. This work assessed the average exposure of 35 dentistry students during their training with the aid of LiF:Mg,Cu,P+PTFE thermoluminescent dosimeters. For the students in the roles of dentist and observers, maximum accumulated equivalent dose obtained was 2.59±0.11 and 4.64±0.39 mSv, respectively. Students in the role as patients received a maximum accumulated effective dose of 28.41±0.31 mSv. If compared to occupational dose limits, this latter value is 56% of the recommended value of 50 mSv in any year. It was found that in all cases, values of equivalent dose to the women breasts were equal to the background dose. Results are discussed and compared to previous published work. Suggested recommendations were given to authorities in order to minimize exposure of the students in the role as patients. - Highlights: • Dose of training dentistry students was estimated with LiF:Mg,Cu,P+PTFE dosimeters. • The average effective dose of students in the role of patient was also estimated. • The sum of organ doses from TL measurements is considered as the whole body dose. • The uncertainty in the results was less than 2%.

  16. Characterization, Exposure Measurement and Control for Nanoscale Particles in Workplaces and on the Road

    International Nuclear Information System (INIS)

    Wang Jing; Pui, David Y H

    2011-01-01

    The amount of engineered nanoparticles is increasing at a rapid rate and more concerns are being raised about the occupational health and safety of nanoparticles in the workplace, and implications of nanotechnology on the environment and living systems. At the same time, diesel engine emissions are one of the serious air pollution sources in urban area. Ultrafine particles on the road can result in harmful effects on the health of drivers and passengers. Research on characterization, exposure measurement and control is needed to address the environmental, health and safety issues of nanoscale particles. We present results of our studies on airborne particles in workplaces and on the road.

  17. Use of the Long Duration Exposure Facility's thermal measurement system for the verification of thermal models

    Science.gov (United States)

    Berrios, William M.

    1992-01-01

    The Long Duration Exposure Facility (LDEF) postflight thermal model predicted temperatures were matched to flight temperature data recorded by the Thermal Measurement System (THERM), LDEF experiment P0003. Flight temperatures, recorded at intervals of approximately 112 minutes for the first 390 days of LDEF's 2105 day mission were compared with predictions using the thermal mathematical model (TMM). This model was unverified prior to flight. The postflight analysis has reduced the thermal model uncertainty at the temperature sensor locations from +/- 40 F to +/- 18 F. The improved temperature predictions will be used by the LDEF's principal investigators to calculate improved flight temperatures experienced by 57 experiments located on 86 trays of the facility.

  18. Ionizing radiations and health. Exposures, epidemiological surveillance and sociological monitoring measurements

    International Nuclear Information System (INIS)

    Spira, Alfred; Boutou, Odile

    1999-01-01

    This paper draws attention to the epidemiological effect of natural and artificial ionizing radiation exposures on man. It describes ionizing radiation sources from nuclear facilities and medical establishments. The case here is in the region of La Hague in France where 4800 employees are exposed to ionizing radiations. The topic of leukemia research and thyroid studies for children in the region are discussed. The impact of radiations on fertility, life quality is covered. Finally, national propositions to establish a monitoring measurement system is also discussed including the personnel and the general population exposed

  19. Characterization, Exposure Measurement and Control for Nanoscale Particles in Workplaces and on the Road

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jing [Institute of Environmental Engineering, ETH Zuerich, 8093 (Switzerland); Pui, David Y H, E-mail: jing.wang@ifu.baug.ethz.ch [Particle Technology Laboratory, University of Minnesota, 55414 (United States)

    2011-07-06

    The amount of engineered nanoparticles is increasing at a rapid rate and more concerns are being raised about the occupational health and safety of nanoparticles in the workplace, and implications of nanotechnology on the environment and living systems. At the same time, diesel engine emissions are one of the serious air pollution sources in urban area. Ultrafine particles on the road can result in harmful effects on the health of drivers and passengers. Research on characterization, exposure measurement and control is needed to address the environmental, health and safety issues of nanoscale particles. We present results of our studies on airborne particles in workplaces and on the road.

  20. Correct measurement of RF-exposure, caused by modern broadband radio systems; Korrekte Erfassung der Immissionen von modernen, breitbandigen Funksystemen

    Energy Technology Data Exchange (ETDEWEB)

    Wuschek, M. [Fachhochschule Deggendorf (Germany)

    2004-07-01

    Correct measurement of exposure, caused by modern broadband radio systems (UMTS, DAB, DVB-T, WLAN) requires special measuring-techniques. Looking at UMTS mobile communication systems as example, in this article the minimum requirements on measuring equipment will be shown. Additional hints were given, in which way an extrapolation of measurement field-levels to maximum installation power is possible. (orig.)

  1. Computational strategy for quantifying human pesticide exposure based upon a saliva measurement

    Energy Technology Data Exchange (ETDEWEB)

    Timchalk, Charles; Weber, Thomas J.; Smith, Jordan N.

    2015-05-27

    The National Research Council of the National Academies report, Toxicity Testing in the 21st Century: A Vision and Strategy, highlighted the importance of quantitative exposure data for evaluating human toxicity risk and noted that biomonitoring is a critical tool for quantitatively evaluating exposure from both environmental and occupational settings. Direct measurement of chemical exposures using personal monitoring provides the most accurate estimation of a subject’s true exposure, and non-invasive methods have also been advocated for quantifying the pharmacokinetics and bioavailability of drugs and xenobiotics. In this regard, there is a need to identify chemicals that are readily cleared in saliva at concentrations that can be quantified to support the implementation of this approach.. The current manuscript describes the use of computational modeling approaches that are closely coupled to in vivo and in vitro experiments to predict salivary uptake and clearance of xenobiotics. The primary mechanism by which xenobiotics leave the blood and enter saliva is thought to involve paracellular transport, passive transcellular diffusion, or trancellular active transport with the majority of drugs and xenobiotics cleared from plasma into saliva by passive diffusion. The transcellular or paracellular diffusion of unbound chemicals in plasma to saliva has been computational modeled using a combination of compartmental and physiologically based approaches. Of key importance for determining the plasma:saliva partitioning was the utilization of a modified Schmitt algorithm that calculates partitioning based upon the tissue composition, pH, chemical pKa and plasma protein-binding. Sensitivity analysis of key model parameters specifically identified that both protein-binding and pKa (for weak acids and bases) had the most significant impact on the determination of partitioning and that there were clear species dependent differences based upon physiological variance between

  2. Food and beverage TV advertising to young children: Measuring exposure and potential impact.

    Science.gov (United States)

    Harris, Jennifer L; Kalnova, Svetlana S

    2018-04-01

    Children of all ages are vulnerable to influence from exposure to unhealthy food advertisements, but experts raise additional concerns about children under 6 due to their more limited cognitive abilities. Most companies in the U.S. Children's Food and Beverage Advertising Initiative (CFBAI) industry self-regulatory program pledge to not direct any advertising to children under 6. However, young children also watch programming primarily directed to older children and thus may view food-related advertising despite companies' pledges. Research is required to understand the amount and potential impact of this exposure on preschool-age children. Study 1 uses Nielsen advertising exposure data to compare preschoolers' (2-5 years) and older children's (6-11 years) exposure to food advertising in 2015. Preschoolers viewed on average 3.2 food ads daily on children's programming, just 6% fewer compared to 6- to 11-year-olds; over 60% were placed by CFBAI-participating companies. Study 2 exposed young children (N = 49) in a child-care setting to child-directed food ads, measured their attitudes about the ads and advertised brands, and compared responses by 4- to 5-year-olds and 6- to 7-year olds. Most children indicated that they liked the child-directed ads, with media experience associated with greater liking for both age groups. Ad liking and previous consumption independently predicted brand liking for both age groups, although previous consumption was a stronger predictor for older children. Despite pledges by food companies to not direct advertising to children under age 6, preschoolers continue to view advertisements placed by these companies daily, including on children's programming. This advertising likely increases children's preferences for nutritionally poor advertised brands. Food companies and media companies airing children's programming should do more to protect young children from advertising that takes advantage of their vulnerabilities. Copyright © 2017

  3. Real-time measurement of outdoor worker's exposure to solar ultraviolet radiation in Pretoria, South Africa

    Directory of Open Access Journals (Sweden)

    Mmathapelo Makgabutlane

    2015-05-01

    Full Text Available The city of Pretoria in South Africa receives considerable solar ultraviolet radiation (UVR because of its low latitude (22–35°S and relatively clear skies. Certain meteorological factors affect the amount of solar UVR that reaches the ground; the most dominant factors being stratospheric ozone, cloud cover and solar zenith angle. It is known that overexposure to solar UVR may lead to the development of adverse health conditions, the most significant being skin cancer. Outdoor workers spend a significant amount of time outside and are thus susceptible to this risk. In this case study, we estimated, for the first time, the real-time solar UVR exposure of an outdoor worker in Pretoria. Measurements were made on 27 and 28 May 2013 using a handheld ultraviolet index (UVI meter calibrated against a science-grade biometer at the South African Weather Service in Pretoria. Personal exposure estimation was used to discern the pattern in diurnal and annual sunburn risk for the outdoor worker. Ambient UVR levels ranged from 0 UVI to 4.66 UVI and the outdoor worker’s potential exposure estimates regularly exceeded 80% of these levels depending on the time of day. The risk of sunburn was evident; however, actual incidents would depend on individual skin photosensitivity and melanin content, as well as sun protection used. Further research is needed to determine the personal exposure estimations of outdoor workers in other provinces in which solar UVR levels may be equally high, or higher than those in Pretoria.

  4. Solar Flare Track Exposure Ages in Regolith Particles: A Calibration for Transmission Electron Microscope Measurements

    Science.gov (United States)

    Berger, Eve L.; Keller, Lindsay P.

    2015-01-01

    Mineral grains in lunar and asteroidal regolith samples provide a unique record of their interaction with the space environment. Space weathering effects result from multiple processes including: exposure to the solar wind, which results in ion damage and implantation effects that are preserved in the rims of grains (typically the outermost 100 nm); cosmic ray and solar flare activity, which result in track formation; and impact processes that result in the accumulation of vapor-deposited elements, impact melts and adhering grains on particle surfaces. Determining the rate at which these effects accumulate in the grains during their space exposure is critical to studies of the surface evolution of airless bodies. Solar flare energetic particles (mainly Fe-group nuclei) have a penetration depth of a few millimeters and leave a trail of ionization damage in insulating materials that is readily observable by transmission electron microscope (TEM) imaging. The density of solar flare particle tracks is used to infer the length of time an object was at or near the regolith surface (i.e., its exposure age). Track measurements by TEM methods are routine, yet track production rate calibrations have only been determined using chemical etching techniques [e.g., 1, and references therein]. We used focused ion beam-scanning electron microscope (FIB-SEM) sample preparation techniques combined with TEM imaging to determine the track density/exposure age relations for lunar rock 64455. The 64455 sample was used earlier by [2] to determine a track production rate by chemical etching of tracks in anorthite. Here, we show that combined FIB/TEM techniques provide a more accurate determination of a track production rate and also allow us to extend the calibration to solar flare tracks in olivine.

  5. Computational Strategy for Quantifying Human Pesticide Exposure based upon a Saliva Measurement

    Directory of Open Access Journals (Sweden)

    Charles eTimchalk

    2015-05-01

    Full Text Available Quantitative exposure data is important for evaluating toxicity risk and biomonitoring is a critical tool for evaluating human exposure. Direct personal monitoring provides the most accurate estimation of a subject’s true dose, and non-invasive methods are advocated for quantifying exposure to xenobiotics. In this regard, there is a need to identify chemicals that are cleared in saliva at concentrations that can be quantified to support the implementation of this approach. This manuscript reviews the computational modeling approaches that are coupled to in vivo and in vitro experiments to predict salivary uptake and clearance of xenobiotics and provides additional insight on species-dependent differences in partitioning that are of key importance for extrapolation. The primary mechanism by which xenobiotics leave the blood and enter saliva involves paracellular transport, passive transcellular diffusion, or trancellular active transport with the majority of xenobiotics transferred by passive diffusion. The transcellular or paracellular diffusion of unbound chemicals in plasma to saliva has been computationally modeled using compartmental and physiologically based approaches. Of key importance for determining the plasma:saliva partitioning was the utilization of the Schmitt algorithm that calculates partitioning based upon the tissue composition, pH, chemical pKa and plasma protein-binding. Sensitivity analysis identified that both protein-binding and pKa (for weak acids and bases have significant impact on determining partitioning and species dependent differences based upon physiological variance. Future strategies are focused on an in vitro salivary acinar cell based system to experimentally determine and computationally predict salivary gland uptake and clearance for xenobiotics. It is envisioned that a combination of salivary biomonitoring and computational modeling will enable the non-invasive measurement of chemical exposures in human

  6. Purex process solvent: literature review

    Energy Technology Data Exchange (ETDEWEB)

    Geier, R.G.

    1979-10-01

    This document summarizes the data on Purex process solvent presently published in a variety of sources. Extracts from these various sources are presented herein and contain the work done, the salient results obtained, and the original, unaltered conclusions of the author of each paper. Three major areas are addressed: solvent stability, solvent quality testing, and solvent treatment processes. 34 references, 44 tables.

  7. Purex process solvent: literature review

    International Nuclear Information System (INIS)

    Geier, R.G.

    1979-10-01

    This document summarizes the data on Purex process solvent presently published in a variety of sources. Extracts from these various sources are presented herein and contain the work done, the salient results obtained, and the original, unaltered conclusions of the author of each paper. Three major areas are addressed: solvent stability, solvent quality testing, and solvent treatment processes. 34 references, 44 tables

  8. The influence of solvent processing on polyester bioabsorbable polymers.

    Science.gov (United States)

    Manson, Joanne; Dixon, Dorian

    2012-01-01

    Solvent-based methods are commonly employed for the production of polyester-based samples and coatings in both medical device production and research. The influence of solvent casting and subsequent drying time was studied using thermal analysis, spectroscopy and weight measurement for four grades of 50 : 50 poly(lactic-co-glycolic acid) (PLGA) produced by using chloroform, dichloromethane, and acetone. The results demonstrate that solvent choice and PLGA molecular weight are critical factors in terms of solvent removal rate and maintaining sample integrity, respectively. The protocols widely employed result in high levels of residual solvent and a new protocol is presented together with solutions to commonly encountered problems.

  9. Can a rapid measure of self-exposure to drugs of abuse provide dimensional information on depression comorbidity?

    Science.gov (United States)

    Butelman, Eduardo Roque; Bacciardi, Silvia; Maremmani, Angelo Giovanni Icro; Darst-Campbell, Maya; Correa da Rosa, Joel; Kreek, Mary Jeanne

    2017-09-01

    Addictions to heroin or to cocaine are associated with substantial psychiatric comorbidity, including depression. Poly-drug self-exposure (eg, to heroin, cocaine, cannabis, or alcohol) is also common, and may further affect depression comorbidity. This case-control study examined the relationship of exposure to the above drugs and depression comorbidity. Participants were recruited from methadone maintenance clinics, and from the community. Adult male and female participants (n = 1,201) were ascertained consecutively by experienced licensed clinicians. The instruments used were the SCID-I, and Kreek-McHugh-Schluger-Kellogg (KMSK) scales, which provide a rapid dimensional measure of maximal lifetime self-exposure to each of the above drugs. This measure ranges from no exposure to high unit dose, high frequency, and long duration of exposure. A multiple logistic regression with stepwise variable selection revealed that increasing exposure to heroin or to cocaine was associated greater odds of depression, with all cases and controls combined. In cases with an opioid dependence diagnosis, increasing cocaine exposure was associated with a further increase in odds of depression. However, in cases with a cocaine dependence diagnosis, increasing exposure to either cannabis or alcohol, as well as heroin, was associated with a further increase in odds of depression. This dimensional analysis of exposure to specific drugs provides insights on depression comorbidity with addictive diseases, and the impact of poly-drug exposure. A rapid analysis of exposure to drugs of abuse reveals how specific patterns of drug and poly-drug exposure are associated with increasing odds of depression. This approach detected quantitatively how different patterns of poly-drug exposure can result in increased odds of depression comorbidity, in cases diagnosed with opioid versus cocaine dependence. (Am J Addict 2017;26:632-639). © 2017 American Academy of Addiction Psychiatry.

  10. Measuring personal exposure from 900MHz mobile phone base stations in Australia and Belgium using a novel personal distributed exposimeter

    NARCIS (Netherlands)

    Bhatt, Chhavi Raj; Thielens, Arno; Redmayne, Mary; Abramson, Michael J; Billah, Baki; Sim, Malcolm R; Vermeulen, Roel; Martens, Luc; Joseph, Wout; Benke, Geza

    2016-01-01

    The aims of this study were to: i) measure personal exposure in the Global System for Mobile communications (GSM) 900MHz downlink (DL) frequency band with two systems of exposimeters, a personal distributed exposimeter (PDE) and a pair of ExpoM-RFs, ii) compare the GSM 900MHz DL exposures across

  11. Measurement of the quantity of water in organic solvents by infrared absorption an measurement of the dielectric constants; Dosage de l'eau dans les solvants organiques par absorption infra-rouge et mesure des constantes dielectriques

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-06-15

    Some chemical methods for the analysis of the quantity of water in solvents are first described, their object being the determination of the maximum error for cases where the water content is less than 1 per cent. - The first part of the work consists in describing infrared spectrometry as applied to the analysis of water in carbon tetrachloride, chloroform aniline, acetone and dioxane. A method based on isotopic exchange between heavy and light water is used on the one hand for determining the solubility of water in carbon tetrachloride and on the other hand for establishing standard solutions (sensitivity of the method). - In the second part the dielectric constant of water solvent solutions is measured. A table is presented giving the precision obtained by the two principal methods. These are comparable and further than that the appearance of the spectra suggests an interpretation of the anomalies observed in calibration curves obtained by the dielectric constant method. (author) [French] Quelques methodes chimiques d'analyses de l'eau dissoute dans les solvants sont decrites tout d'abord en vue de determiner l'erreur maxima dans le cas ou la teneur en eau ne depasse pas 1 pour cent. - Une premiere partie du travail expose la technique utilisee en spectrometrie infrarouge pour doser l'eau dans le tetrachlorure de carbone, chloroforme, aniline, acetone et le dioxane. Une methode basee sur l'echange isotopique entre l'eau legere et l'eau lourde permet de determiner d'une part la solubilite de l'eau dans le tetrachlorure de carbone et le chloroforme et d'autre part le titre en valeur absolue des solutions etalons (sensibilite de la methode). - Dans une deuxieme partie, on mesure la constante dielectrique des solutions eau-solvant. On dresse un tableau des precisions obtenues par les deux methodes principales. Celles-ci sont comparables et en outre, l'aspect du spectre suggere une interpretation des anomalies observees dans les courbes d'etalonnage tracees par la

  12. Environmental tobacco smoke in designated smoking areas in the hospitality industry: exposure measurements, exposure modelling and policy assessment.

    Science.gov (United States)

    McNabola, A; Eyre, G J; Gill, L W

    2012-09-01

    Tobacco control policy has been enacted in many jurisdictions worldwide banning smoking in the workplace. In the hospitality sector many businesses such as bars, hotels and restaurants have installed designated smoking areas on their premises and allowance for such smoking areas has been made in the tobacco control legislation of many countries. An investigation was carried out into the level of exposure to environmental tobacco smoke (ETS) present in 8 pubs in Ireland which included designated smoking areas complying with two different definitions of a smoking area set out in Irish legislation. In addition, ETS exposure in a pub with a designated smoking area not in compliance with the legislation was also investigated. The results of this investigation showed that the two differing definitions of a smoking area present in pubs produced similar concentrations of benzene within smoking areas (5.1-5.4 μg/m(3)) but differing concentrations within the 'smoke-free' areas (1.42-3.01 μg/m(3)). Smoking areas in breach of legislative definitions were found to produce the highest levels of benzene in the smoking area (49.5 μg/m(3)) and 'smoke-free' area (7.68 μg/m(3)). 3D exposure modelling of hypothetical smoking areas showed that a wide range of ETS exposure concentrations were possible in smoking areas with the same floor area and same smoking rate but differing height to width and length to width ratios. The results of this investigation demonstrate that significant scope for improvement of ETS exposure concentrations in pubs and in smoking areas may exist by refining and improving the legislative definitions of smoking areas in law. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Exploratory study on a statistical method to analyse time resolved data obtained during nanomaterial exposure measurements

    International Nuclear Information System (INIS)

    Clerc, F; Njiki-Menga, G-H; Witschger, O

    2013-01-01

    Most of the measurement strategies that are suggested at the international level to assess workplace exposure to nanomaterials rely on devices measuring, in real time, airborne particles concentrations (according different metrics). Since none of the instruments to measure aerosols can distinguish a particle of interest to the background aerosol, the statistical analysis of time resolved data requires special attention. So far, very few approaches have been used for statistical analysis in the literature. This ranges from simple qualitative analysis of graphs to the implementation of more complex statistical models. To date, there is still no consensus on a particular approach and the current period is always looking for an appropriate and robust method. In this context, this exploratory study investigates a statistical method to analyse time resolved data based on a Bayesian probabilistic approach. To investigate and illustrate the use of the this statistical method, particle number concentration data from a workplace study that investigated the potential for exposure via inhalation from cleanout operations by sandpapering of a reactor producing nanocomposite thin films have been used. In this workplace study, the background issue has been addressed through the near-field and far-field approaches and several size integrated and time resolved devices have been used. The analysis of the results presented here focuses only on data obtained with two handheld condensation particle counters. While one was measuring at the source of the released particles, the other one was measuring in parallel far-field. The Bayesian probabilistic approach allows a probabilistic modelling of data series, and the observed task is modelled in the form of probability distributions. The probability distributions issuing from time resolved data obtained at the source can be compared with the probability distributions issuing from the time resolved data obtained far-field, leading in a

  14. Enhancement of catalytic efficiency of enzymes through exposure to anhydrous organic solvent at 70 degrees C. Three-dimensional structure of a treated serine proteinase at 2.2 A resolution.

    Science.gov (United States)

    Gupta, M N; Tyagi, R; Sharma, S; Karthikeyan, S; Singh, T P

    2000-05-15

    The enzyme behavior in anhydrous media has important applications in biotechnology. So far chemical modifications and protein engineering have been used to alter the catalytic power of the enzymes. For the first time, it is demonstrated that an exposure of enzyme to anhydrous organic solvents at optimized high temperature enhances its catalytic power through local changes at the binding region. Six enzymes: proteinase K, wheat germ acid phosphatase, alpha-amylase, beta-glucosidase, chymotrypsin and trypsin have been exposed to acetonitrile at 70 degrees C for three hours. The activities of these enzymes were found to be considerably enhanced. In order to understand the basis of this change in the activity of these enzymes, the structure of one of these treated enzymes, proteinase K has been analyzed in detail using X-ray diffraction method. The overall structure of the enzyme is similar to the native structure in aqueous environment. The hydrogen bonding system of the catalytic triad is intact after the treatment. However, the water structure in the substrate binding site undergoes some rearrangement as some of the water molecules are either displaced or completely absent. The most striking observation concerning the water structure pertains to the complete deletion of the water molecule which occupied the position at the so-called oxyanion hole in the active site of the native enzyme. Three acetonitrile molecules were found in the present structure. All the acetonitrile molecules are located in the recognition site. The sites occupied by acetonitrile molecules are independent of water molecules. The acetonitrile molecules are involved in extensive interactions with the protein atoms. All of them are interlinked through water molecules. The methyl group of one of the acetonitrile molecules (CCN1) interacts simultaneously with the hydrophobic side chains of Leu-96, Ile-107, and Leu-133. The development of such a hydrophobic environment at the recognition site

  15. Dosemetry for exposures to cosmic radiation in civilian aircraft - Part 1: Conceptual basis for measurements

    International Nuclear Information System (INIS)

    2006-01-01

    Aircraft crew are exposed to elevated levels of cosmic radiation of galactic and solar origin and secondary radiation produced in the atmosphere, the aircraft structure and its contents. Following recommendations of the International Commission on Radiological Protection in Publication 60, the European Union (EU) introduced a revised Basic Safety Standards Directive, which included exposure to natural sources of ionizing radiation, including cosmic radiation, as occupational exposure. The Directive requires account to be taken of the exposure of aircraft crew liable to receive more than 1 mSv per year. It then identifies the following four protection measures: (i) to assess the exposure of the crew concerned; (ii) to take into account the assessed exposure, when organizing working schedules with a view to reducing the doses of highly exposed crew; (iii) to inform the workers concerned of the health risks their work involves; and (iv) to apply the same special protection during pregnancy to female crew in respect of the 'child to be born' as to other female workers. The EU Council Directive has already been incorporated into laws and regulations of EU Member States and is being included in the aviation safety standards and procedures of the Joint Aviation Authorities and the European Air Safety Agency. For regulatory and legislative purposes, the radiation protection quantities of interest are equivalent dose (to the foetus) and effective dose. The cosmic radiation exposure of the body is essentially uniform and the maternal abdomen provides no effective shielding to the foetus. As a result, the magnitude of equivalent dose to the foetus can be put equal to that of the effective dose received by the mother. Doses on board aircraft are generally predictable, and events comparable to unplanned exposure in other radiological workplaces cannot normally occur (with the rare exceptions of extremely intense and energetic solar particle events). Personal dosemeters for

  16. High beta radiation exposure of medical staff measures for optimisation of radiation protection

    International Nuclear Information System (INIS)

    Barth, I.; Rimpler, A.

    2006-01-01

    Full text of publication follows: New therapies applying beta radionuclides have been introduced in medicine in recent years, especially in nuclear medicine, e. g. radio-synoviorthesis, radioimmunotherapy and palliative pain therapy. The preparation of radiopharmaceuticals, their dispensary as well as injection require the handling of vials and syringes with high activities of beta emitters at small distances to the skin. Thus the medical staff may be exposed to a high level of beta radiation. Hence the local skin dose, Hp(0,07), was measured at these workplaces with thin-layer thermoluminescent dosemeters TLD (LiF:Mg,P,Cu) fixed to the tip of the fingers at both hands of the personnel. In addition, official beta/photon ring dosemeters were worn at the first knuckle of the index finger. Very high local skin doses were measured at the tip of index finger and thumb. The findings indicate that the exposure of the staff can exceed the annual dose limit for skin of 500 mSv when working at a low protection standard. By the use of appropriate shieldings and tools (e.g. tweezers or forceps) the exposure was reduced of more than one order of magnitude. The German dosimetry services provide official beta/photon ring dosemeters for routine monitoring of the extremity exposure of occupationally exposed persons. But even monitoring with these official dosemeters does not provide suitable results to control compliance with the dose limit in the majority of cases because they can mostly not be worn at the spot of highest beta exposure (finger tip). Therefore, a study was performed to identify the difference of readings of official ring dosemeters and the maximum local skin dose at the finger tips. At workplaces of radio-synoviorthesis a correction factor of 3 was determined provided that the staff worked at high radiation protection standard and the ring dosemeters were worn at the first knuckle of the index finger. The correction factor increases significantly when the radiation

  17. Study of measurement methods of ultrafine aerosols surface-area for characterizing occupational exposure

    International Nuclear Information System (INIS)

    Bau, S.

    2008-12-01

    This work aims at improving knowledge on ultrafine aerosols surface-area measurement. Indeed, the development of nano-technologies may lead to occupational exposure to airborne nano-structured particles, which involves a new prevention issue. There is currently no consensus concerning what parameter (mass, surface-area, number) should be measured. However, surface-area could be a relevant metric, since it leads to a satisfying correlation with biological effects when nano-structured particles are inhaled. Hence, an original theoretical work was performed to position the parameter of surface-area in relation to other aerosol characteristics. To investigate measurement techniques of nano-structured aerosols surface-area, the experimental facility CAIMAN (Characterization of Instruments for the Measurement of Aerosols of Nano-particles) was designed and built. Within CAIMAN, it is possible to produce nano-structured aerosols with varying and controlled properties (size, concentration, chemical nature, morphology, state-of-charge), stable and reproducible in time. The generated aerosols were used to experimentally characterize the response of the instruments in study (NSAM and AeroTrak 9000 TSI, LQ1-DC Matter Engineering). The response functions measured with monodisperse aerosols show a good agreement with the corresponding theoretical curves in a large size range, from 15 to 520 nm. Furthermore, hypotheses have been formulated to explain the reasonable biases observed when measuring poly-disperse aerosols. (author)

  18. Measurements of national radiation exposure rates on train lines in Tokai area

    International Nuclear Information System (INIS)

    Matsuda, Hideharu

    1996-01-01

    For data accumulation of natural radiation exposure rate derived from gamma-ray and cosmic-ray to evaluate population dose, the author measured the rate in the running vehicles of 12 JR Tokai lines, 17 Nagoya Railway lines, 4 Kinkinippon Railway lines and 1 line of Nagoya City Bus. A portable gamma spectrometer equipped with 3' in diameter x 3' NaI (Tl) scintillation detector was placed on the seat of the vehicle for measurement in the period of December, 1992-August, 1995. Gamma-ray and cosmic-ray exposure rates in air were assessed separately as reported before and expressed in Gy/h. The average exposure rate of gamma-ray in JR Tokai lines was 19.8 nGy/h and of cosmic-ray, 28.5 nGy/h, both of which were markedly varied from line to line. The average rates of gamma-and cosmic-ray were 21.6 nGy/h and 29.0 nGy/h, respectively, in Nagoya Railway lines and 20.9 nGy/h and 28.7 nGy/h, respectively, in Kinkinippon lines. In the city bus, the respective rates were 27.2 nGy/h and 27.0 nGy/h. Thus, the average rates of gamma-ray (about 20 nGy/h) and cosmic-ray (about 29 nGy/h) were not so different between JR and other private railway lines. In the bus, the former rate was slightly lower and the latter, slightly higher. However, the total rates of both rays were in the range of about 50-55 nGy/h in all vehicles examined. (H.O.)

  19. Ultra-trace measurement of Dechloranes to investigate food as a route of human exposure.

    Science.gov (United States)

    L'Homme, Benjamin; Calaprice, Chiara; Calvano, Cosima Damiana; Zambonin, Carlo; Leardi, Riccardo; Focant, Jean-François

    2015-11-01

    Dechloranes, including Dechlorane Plus (syn- and anti-isomers), Dechlorane 602, Dechlorane 603, Dechlorane 604, Chlordene Plus, and Mirex are used as flame-retardants and were recently found in human serum of the European population. In order to investigate if food consumption would possibly be a significant route of exposure, we developed a method for the measurement of Dechloranes in food and feed. We showed that it was possible to extend the scope of the regular polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin like (DL-), and non-dioxin like (NDL-) regulated PCBs clean-up and fractionation procedure to Dechloranes and that no compound degradation occurred during the strong acidic treatments used for lipid digestion. Dechloranes were measured by gas chromatography coupled to triple quadrupole mass spectrometry (GC-QQQMS/MS). We optimized injection parameters by face centered experimental design (FCD). The electron ionization fragmentation was investigated to set appropriate multiple reaction monitoring (MRM) transitions. Instrumental and method limits of quantitation (iLOQs and mLOQs) were determined following EU guidelines for dioxin analyses in food. A total of 88 samples were analyzed to assess the prevalence of this route of exposure to humans. Average levels of the sum of Dechloranes ranged from 10 to 31pg/g fat, with the exception of fish, feed additives, and corn that were reported in pg/g wet weight at average levels of 9, 12, and 2pg/g ww. Based on Belgian food habits, a dietary intake was estimated to be 136pg/day. The relatively low reported levels indicate that other routes of human exposure should be considered. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Exposure to environmental tobacco smoke measured by cotinine 125I-radioimmunoassay

    International Nuclear Information System (INIS)

    Knight, G.J.; Palomaki, G.E.; Lea, D.H.; Haddow, J.E.

    1989-01-01

    We describe a polyclonal-antiserum-based 125 I-radioimmunoassay for cotinine that is suitable for measuring nonsmokers' passive exposure to tobacco smoke in the environment. The standard curve ranged from 0.25 to 12.0 micrograms/L, with an estimated lower limit of sensitivity of 0.2 microgram/L (95% B/Bo = 0.2 microgram/L; 50% B/Bo = 4.0 micrograms/L). The median within-assay CVs for patients' samples with cotinine values from 0.4 to 1.3, 1.4 to 2.4, 2.5 to 4.6, and 4.7 to 15.6 micrograms/L were 13.9%, 7.2%, 5.1%, and 5.7%, respectively. Between-assay CVs for two quality-control sera with average values of 1.53 and 3.68 micrograms/L were 14.3% and 7.8%, respectively. Analytical recoveries of cotinine from smokers' sera diluted in zero calibrant ranged from 91% to 116%. Cotinine values determined on 79 paired sera and urines from nonsmokers showed significant correlation with self-reported exposure to environmental tobacco smoke (r = 0.49, P less than 0.001 for sera; r = 0.57, P less than 0.001 for urine). The log of the values for serum and urine cotinine were also significantly correlated (r = 0.85, P less than 0.001). Evidently, polyclonal antiserum can be used to develop a cotinine assay for measuring exposure to environmental tobacco smoke that compares well with that described for monoclonal-based assays

  1. Measuring adolescents’ exposure to victimization: The Environmental Risk (E-Risk) Longitudinal Twin Study

    Science.gov (United States)

    Fisher, Helen L.; Caspi, Avshalom; Moffitt, Terrie E.; Wertz, Jasmin; Gray, Rebecca; Newbury, Joanne; Ambler, Antony; Zavos, Helena; Danese, Andrea; Mill, Jonathan; Odgers, Candice L.; Pariante, Carmine; Wong, Chloe C.; Arseneault, Louise

    2016-01-01

    This paper presents mutlilevel findings on adolescents’ victimization exposure from a large longitudinal cohort of twins. Data were obtained from the Environmental Risk (E-Risk) Longitudinal Twin Study, an epidemiological study of 2,232 children (1,116 twin pairs) followed to 18 years of age (with 93% retention). To assess adolescent victimization we combined best practices in survey research on victimization with optimal approaches to measuring life stress and traumatic experiences, and introduce a reliable system for coding severe victimization. One in three children experienced at least one type of severe victimization during adolescence (crime victimization, peer/sibling victimization, internet/mobile phone victimization, sexual victimization, family violence, maltreatment, or neglect), and most types of victimization were more prevalent amongst children from low socioeconomic backgrounds. Exposure to multiple victimization types was common, as was re-victimization; over half of those physically maltreated in childhood were also exposed to severe physical violence in adolescence. Biometric twin analyses revealed that environmental factors had the greatest influence on most types of victimization, while severe physical maltreatment from caregivers during adolescence was predominantly influenced by heritable factors. The findings from this study showcase how distinct levels of victimization measurement can be harmonized in large-scale studies of health and development. PMID:26535933

  2. Risk assessment of exposure to mechanical vibrations: comparison between field measurements and use of databases

    International Nuclear Information System (INIS)

    Monica, L.; Nataletti, P.; Vignali, G.

    2008-01-01

    Despite continuous technological progress with a view to guaranteeing workers' safety and health, there are still many hazardous situations to workers' health when using industrial equipment; exposure to mechanical vibrations may definitely be included among these situations. Many researches have shown that the widespread use of various vibrating tools in the industrial, agricultural and forestry fields, such as vehicles and machinery in the workplace, are a source of vibration disorders or the worsening of pre-existing symptoms.The aim of this paper is to present a comparison between the two types of risk assessment currently provided for by the law: direct field measurements and database support. We will identify the advantages and operational limitations involved in the use of databases through the results of direct field measurements assessing the risk derived from vibrations in a typical engineering company in the mineral waters and beverages industry. As a result, this research can represent a functional reference for risk assessments of vibration exposure in individual companies

  3. Comparison of gamma-ray exposure rate measurements at Bikini Atoll

    International Nuclear Information System (INIS)

    Gudiksen, P.H.; Crites, T.R.

    1975-01-01

    A radiological survey of Bikini and Eneu Islands of the Bikini Atoll was conducted during June 1975 to assess the potential radiation doses that may be received by the returning Bikinians. Bikini Atoll was one of the U.S. nuclear weapons testing sites in the Pacific. An integral part of the survey included measurements of the gamma-ray exposure rates at 1 m above the ground with portable NaI instruments at nearly 2700 locations on the two islands. For comparison purposes, similar measurements were made with a pressurized ion chamber at approximately 200 locations, and with LiF and CaF 2 :Dy thermoluminescent dosimeters (TLDs) at 80 locations. The results indicate that the NaI scintillators overresponded because of their nonlinear energy characteristics. The responses of the LiF dosimeters and the pressurized ion chamber agreed to within 13 percent. Attenuation studies with LiF TLDs indicated that roughly 25 percent of the total free air exposure rate at 1 m was due to beta radiation

  4. Radioactivity measurements in Egyptian phosphate mines and their significance in the occupational exposure of mine workers

    International Nuclear Information System (INIS)

    Bigu, J.; Hussein, Mohamed I.; Hussein, A.Z.

    2000-01-01

    Radioactivity measurements have been conducted in nine underground phosphate mines in the Egyptian Eastern Desert in order to estimate the occupational radiation exposure of mine workers in those mining sites. Measurements were carried out of airborne radon ( 222 Rn) and its short-lived decay products (progeny) and thoron ( 220 Rn) progeny, as well as γ-radiation from mine walls, ceilings and floors. Comparison of experimental data and theoretical predictions showed partial agreement between these two sets of data. This result is partly attributed to the complex layout of these mines which causes undesirable ventilation conditions, such as recirculation airflow patterns which could not be adequately identified or quantified. The radiation data obtained were used to estimate the Maximum Annual Dose (MAD), and other important occupational radiation exposure variables. These calculations indicate that in eight out of the nine mines surveyed, the MAD exceeded (by a factor of up to 7) the maximum recommended level by ICRP-60. A number of suggestions are made in order to reduce the MAD in the affected mines

  5. Toenail as Non-invasive Biomarker in Metal Toxicity Measurement of Welding Fumes Exposure - A Review

    Science.gov (United States)

    Bakri, S. F. Z.; Hariri, A.; Ma'arop, N. F.; Hussin, N. S. A. W.

    2017-01-01

    Workers are exposed to a variety of heavy metal pollutants that are released into the environment as a consequence of workplace activities. This chemical pollutants are incorporated into the human by varies of routes entry and can then be stored and distributed in different tissues, consequently have a potential to lead an adverse health effects and/or diseases. As to minimize the impact, a control measures should be taken to avoid these effects and human biological marker is a very effective tool in the assessment of occupational exposure and potential related risk as the results is normally accurate and reproducible. Toenail is the ideal matrix for most common heavy metals due to its reliability and practicality compared to other biological samples as well as it is a non-invasive and this appears as a huge advantage of toenail as a biomarker. This paper reviews studies that measure the heavy metals concentration in toenail as non-invasive matrix which later may adapt in the investigation of metal fume emitted from welding process. The development of new methodology and modern analytical techniques has allowed the use of toenail as non-invasive approach. The presence of a heavy metal in this matrix reflects an exposure but the correlations between heavy metal levels in the toenail must be established to ensure that these levels are related to the total body burden. These findings suggest that further studies on interactions of these heavy metals in metal fumes utilizing toenail biomarker endpoints are highly warranted especially among welders.

  6. Solubility measurement and correlation of the form A of ibrutinib in organic solvents from 278.15 to 323.15 K

    International Nuclear Information System (INIS)

    Chen, Zhenzhen; Zhai, Jinghuan; Liu, Xijian; Mao, Shimin; Zhang, Lijuan; Rohani, Sohrab; Lu, Jie

    2016-01-01

    Highlights: • The solubility of ibrutinib (form A) in organic solvents was firstly reported. • Apelblat, λh, empirical polynomial equations were used to correlate the solubility. • The solubility order: MEK > acetone > EA > 1-butanol > acetonitrile ≈ IPA > MTBE. - Abstract: In this work, the solubility of the form A of ibrutinib in isopropanol (IPA), 1-butanol, ethyl acetate (EA), acetonitrile, acetone, methyl ethyl ketone (MEK) and methyl tertiary butyl ether (MTBE) was firstly experimentally determined by a gravimetric method in the temperature range from 278.15 to 323.15 K at atmospheric pressure. The experimental solubility data were correlated by several commonly used models including the modified Apelblat equation, the Buchowski-Ksiazczak λh equation and an empirical quartic polynomial equation. The results showed that, in the temperature range investigated, the solubility of ibrutinib generally increased with the increasing temperature, and the solubility order at the room temperature in the studied solvents was: MEK > acetone > ethyl acetate > 1-butanol > acetonitrile ≈ isopropanol > MTBE. In addition, all the models gave satisfactory correlation results, in which the empirical quartic polynomial equation stood out to be more suitable with a higher accuracy than the other two equations.

  7. How to quantify exposure to traumatic stress? Reliability and predictive validity of measures for cumulative trauma exposure in a post-conflict population.

    Science.gov (United States)

    Wilker, Sarah; Pfeiffer, Anett; Kolassa, Stephan; Koslowski, Daniela; Elbert, Thomas; Kolassa, Iris-Tatjana

    2015-01-01

    While studies with survivors of single traumatic experiences highlight individual response variation following trauma, research from conflict regions shows that almost everyone develops posttraumatic stress disorder (PTSD) if trauma exposure reaches extreme levels. Therefore, evaluating the effects of cumulative trauma exposure is of utmost importance in studies investigating risk factors for PTSD. Yet, little research has been devoted to evaluate how this important environmental risk factor can be best quantified. We investigated the retest reliability and predictive validity of different trauma measures in a sample of 227 Ugandan rebel war survivors. Trauma exposure was modeled as the number of traumatic event types experienced or as a score considering traumatic event frequencies. In addition, we investigated whether age at trauma exposure can be reliably measured and improves PTSD risk prediction. All trauma measures showed good reliability. While prediction of lifetime PTSD was most accurate from the number of different traumatic event types experienced, inclusion of event frequencies slightly improved the prediction of current PTSD. As assessing the number of traumatic events experienced is the least stressful and time-consuming assessment and leads to the best prediction of lifetime PTSD, we recommend this measure for research on PTSD etiology.

  8. How to quantify exposure to traumatic stress? Reliability and predictive validity of measures for cumulative trauma exposure in a post-conflict population

    Directory of Open Access Journals (Sweden)

    Sarah Wilker

    2015-11-01

    Full Text Available Background: While studies with survivors of single traumatic experiences highlight individual response variation following trauma, research from conflict regions shows that almost everyone develops posttraumatic stress disorder (PTSD if trauma exposure reaches extreme levels. Therefore, evaluating the effects of cumulative trauma exposure is of utmost importance in studies investigating risk factors for PTSD. Yet, little research has been devoted to evaluate how this important environmental risk factor can be best quantified. Methods: We investigated the retest reliability and predictive validity of different trauma measures in a sample of 227 Ugandan rebel war survivors. Trauma exposure was modeled as the number of traumatic event types experienced or as a score considering traumatic event frequencies. In addition, we investigated whether age at trauma exposure can be reliably measured and improves PTSD risk prediction. Results: All trauma measures showed good reliability. While prediction of lifetime PTSD was most accurate from the number of different traumatic event types experienced, inclusion of event frequencies slightly improved the prediction of current PTSD. Conclusions: As assessing the number of traumatic events experienced is the least stressful and time-consuming assessment and leads to the best prediction of lifetime PTSD, we recommend this measure for research on PTSD etiology.

  9. Measurements of radiation exposure on commercial aircraft with the LIULIN-3M instrument

    International Nuclear Information System (INIS)

    Stassinopoulos, E.G.; Stauffer, C.A.; Dachev, T.P.; Tomov, B.T.; Dimitrov, P.G.; Brucker, G.J.

    1999-01-01

    The LIULIN-3M evolved from an international cooperative project by a group of Bulgarian, Russian, German, and American scientists. The radiometer is a low power, small size, light weight, and low cost instrument composed of a solid state detector (SSD) with supporting electronics that enable it to operate as a pulse height analyzer of energy deposited in the detector, and to obtain from these measurements the total dose or the dose rate produced by charged particles. The instrument has also been used as a low-LET radiation spectrometer for measuring biological doses of potential human exposures. A flash memory allows self-storage of data during flights and post flight retrieval. Results will be presented and discussed. (author)

  10. Solvents, Ethanol, Car Crashes and Tolerance: How Risky is Inhalation of Organic Solvents?

    Science.gov (United States)

    A research program in the National Health and Environmental Effects Research Laboratory of the U.S. EPA has led to some surprising considerations regarding the potential hazard of exposure to low concentrations of solvent vapors. This program involved conducting experiments to ch...

  11. Elemental properties of copper slag and measured airborne exposures at a copper slag processing facility.

    Science.gov (United States)

    Mugford, Christopher; Gibbs, Jenna L; Boylstein, Randy

    2017-08-01

    measures are not taken. To our knowledge, this is the first attempt to characterize exposures associated with copper slag processing. More in-depth air monitoring and health surveillance is needed to understand occupational exposures and health outcomes in this industry.

  12. Evaluation of Toluene Exposure in Workers at Industrial Area of Sidoarjo, Indonesia by Measurement of Urinary Hippuric Acid

    Directory of Open Access Journals (Sweden)

    Moch Sahri

    2013-12-01

    How to cite this article: Sahri M, Widajati N. Evaluation of Toluene Exposure in Workers at Industrial Area of Sidoarjo, Indonesia by Measurement of Urinary Hippuric Acid. Asia Pac J Med Toxicol 2013;2:145-9.

  13. Separation by solvent extraction

    International Nuclear Information System (INIS)

    Holt, C.H. Jr.

    1976-01-01

    In a process for separating fission product values from U and Pu values contained in an aqueous solution, an oxidizing agent is added to the solution to secure U and Pu in their hexavalent state. The aqueous solution is contacted with a substantially water-immiscible organic solvent with agitation while the temperature is maintained at from -1 to -2 0 C until the major part of the water present is frozen. The solid ice phase is continuously separated as it is formed and a remaining aqueous liquid phase containing fission product values and a solvent phase containing Pu and U values are separated from each other. The last obtained part of the ice phase is melted and added to the separated liquid phase. The resulting liquid is treated with a new supply of solvent whereby it is practically depleted of U and Pu

  14. Measurements for assessing the exposure from 3G femto-cells

    International Nuclear Information System (INIS)

    Boursianis, A.; Vanias, P.; Samaras, T.

    2012-01-01

    Femto-cells are low-power access points, which combine mobile and broadband technologies. The main operation of a femto-cell is to function as a miniature base station unit in an indoor environment and to connect to the operator's network through a broadband phone line or a coaxial cable line. This study provides the first experimental measurements and results in Greece for the assessment of exposure to a femto-cell access point (FAP) indoors. Using a mobile handset with the appropriate software, power level measurements of the transmitted (Tx) and the received by the mobile handset signal were performed in two different and typical (home and office) environments. Moreover, radiofrequency electric field strength and frequency selective measurements with a radiation meter (SRM-3000) were carried out in the proximity of the FAP installation point. The cumulative distribution functions of the Tx power at most cases (except one) show that in 90% of all points the power of the mobile phone was lower by at least 7 dB during FAP operation. At a distance of ∼1 m from the FAP (in its main beam), power flux density measurements show that there is very little difference between the two situations (FAP ON and OFF). As a conclusion, the use of femto-cells indoors improves reception quality, reduces the Tx power of the user's mobile terminal and results in an indiscernible increase of the electromagnetic field in front of the unit, at values that are extremely low compared with reference levels of exposure guidelines. (authors)

  15. Determination of Measurement Points in Urban Environments for Assessment of Maximum Exposure to EMF Associated with a Base Station

    Directory of Open Access Journals (Sweden)

    Agostinho Linhares

    2014-01-01

    Full Text Available A base station (BS antenna operates in accordance with the established exposure limits if the values of electromagnetic fields (EMF measured in points of maximum exposure are below these limits. In the case of BS in open areas, the maximum exposure to EMF probably occurs in the antenna’s boresight direction, from a few tens to a few hundred meters away. This is not a typical scenery for urban environments. However, in the line of sight (LOS situation, the region of maximum exposure can still be analytically estimated with good results. This paper presents a methodology for the choice of measurement points in urban areas in order to assess compliance with the limits for exposure to EMF.

  16. Assessing color vision loss among solvent-exposed workers.

    Science.gov (United States)

    Mergler, D; Blain, L

    1987-01-01

    Acquired color vision loss has been associated with exposure to organic solvents in the workplace. However, not all tests of chromatic discrimination loss are designed to detect acquired, as opposed to congenital, loss. The Lanthony D-15 desaturated panel (D-15-d), a simple 15 cap color arrangement test, designed to identify mild acquired dyschromatopsia, can be administered rapidly in the field, under standard conditions. The objective of the present study was to evaluate the D-15-d among 23 solvent-exposed workers of a paint manufacturing plant, by comparing the results obtained with the D-15-d to those obtained with the Farnsworth-Munsell 100 Hue (FM-100), a highly sensitive measure of color vision loss. The D-15-d revealed a significantly higher prevalence of dyschromatopsia among the ten highly exposed workers (80%) as compared to the 13 moderately exposed workers (30.8%); FM-100 results revealed one false positive. All dyschromatopic workers presented blue-yellow loss; the FM-100 detected eight complex patterns, while the D-15-d identified 5. Comparison of D-15-d and FM-100 scores were highly correlated (corr. coeff. 0.87; p less than 0.001). Multiple regression analyses showed both scores to be significantly related to age and exposure level. The findings of this study indicate that the D-15-d is an adequate instrument for field study batteries. However, the FM-100 should be used for more detailed assessment.

  17. Birth outcome measures and prenatal exposure to 4-tert-octylphenol

    International Nuclear Information System (INIS)

    Lv, Shenliang; Wu, Chunhua; Lu, Dasheng; Qi, Xiaojuan; Xu, Hao; Guo, Jianqiu; Liang, Weijiu; Chang, XiuLi

    2016-01-01

    Exposure to 4-tert-octylphenol (tOP) has been linked with adverse health outcomes in animals and humans, while epidemiological studies about associations between prenatal exposure to tOP and fetal growth are extremely limited. We measured urinary tOP concentrations in 1100 pregnant women before their delivery, and examined whether tOP levels were associated with birth outcomes, including weight, length, head circumference and ponderal index at birth. tOP could be detected in all samples, and the median uncorrected and creatinine-corrected tOP concentrations were 0.90 μg/L (range from 0.25 to 20.05 μg/L) and 1.33 μg/g creatinine (range from 0.15 to 42.49 μg/g creatinine), respectively. Maternal urinary log-transformed tOP concentrations were significantly negatively associated with adjusted birth weight [β (g) = −126; 95% confidence interval (CI): −197, −55], birth length [β (cm) = −0.53; 95% CI:−0.93, −0.14], and head circumference [β (cm) = −0.30; 95% CI: −0.54, −0.07], respectively. Additionally, considering sex difference, these significant negative associations were also found among male neonates, while only higher maternal tOP concentrations were associated with a significant decrease in birth weight among female neonates. This study suggested significant negative associations between maternal urinary tOP concentrations and neonatal sizes at birth, and they differed by neonatal sex. Further epidemiological studies are required to more fully elaborate the associations between prenatal tOP exposure and birth outcomes. - Highlights: • We measured 4-tert-octylphenol (tOP) in urine from 1100 Chinese pregnant women. • The associations between maternal tOP levels and birth outcomes were investigated. • Prenatal exposure to tOP in the selected area was widespread at higher levels. • Maternal tOP levels were significantly negatively associated with birth sizes. • The associations between tOP and birth outcomes might

  18. Measurements of children's exposures to particles and nitrogen dioxide in Santiago, Chile

    International Nuclear Information System (INIS)

    Rojas-Bracho, Leonora; Suh, Helen H.; Koutrakis, Petros; Oyola, Pedro

    2002-01-01

    An exposure study of children (aged 10-12 years) living in Santiago, Chile, was conducted. Personal, indoor and outdoor fine and inhalable particulate matter ( 2.5 and 10 , respectively), and nitrogen dioxide (NO 2 ) were measured during pilot (N=8) and main (N=20) studies, which were conducted during the winters of 1998 and 1999, respectively. For the main study, personal indoor and outdoor 24-h samples were collected for five consecutive days. Similar mean personal, indoor and outdoor PM 2.5 concentrations (69.5, 68.5 and 68.1 μg m -3 , respectively) were found. However, for coarse particles (calculated as the difference between measured PM 10 and PM 2.5 , PM 2.5-10 ) indoor and outdoor levels (35.4 and 47.4 μg m -3 ) were lower than their corresponding personal exposures (76.3 μg m -3 ). Indoor and outdoor NO 2 concentrations were comparable (35.8 and 36.9 ppb) and higher than personal exposures (25.9 ppb). Very low ambient indoor and personal O 3 levels were found, which were mostly below the method's limit of detection (LOD). Outdoor particles contributed significantly to indoor concentrations, with effective penetration efficiencies of 0.61 and 0.30 for PM 2.5 and PM 2.5-10 , respectively. Personal exposures were strongly associated with indoor and outdoor concentrations for PM 2.5 , but weakly associated for PM 2.5-10 . For NO 2 , weak associations were obtained for indoor-outdoor and personal-outdoor relationships. This is probably a result of the presence of gas cooking stoves in all the homes. Median I/O, P/I and P/O ratios for PM 2.5 were close to unity, and for NO 2 they ranged between 0.64 and 0.95. These ratios were probably due to high ambient PM 2.5 and NO 2 levels in Santiago, which diminished the relative contribution of indoor sources and subjects' activities to indoor and personal PM 2.5 and NO 2 levels

  19. Measurements of children's exposures to particles and nitrogen dioxide in Santiago, Chile

    Energy Technology Data Exchange (ETDEWEB)

    Rojas-Bracho, Leonora; Suh, Helen H.; Koutrakis, Petros [Harvard University, School of Public Health, 665 Huntington Avenue, 02115 Boston, MA (United States); Oyola, Pedro [Comision Nacional del Medio Ambiente CONAMA, Santiago (Chile)

    2002-03-27

    An exposure study of children (aged 10-12 years) living in Santiago, Chile, was conducted. Personal, indoor and outdoor fine and inhalable particulate matter (<2.5 {mu}m in diameter, PM{sub 2.5} and <10 {mu}m in diameter, PM{sub 10}, respectively), and nitrogen dioxide (NO{sub 2}) were measured during pilot (N=8) and main (N=20) studies, which were conducted during the winters of 1998 and 1999, respectively. For the main study, personal indoor and outdoor 24-h samples were collected for five consecutive days. Similar mean personal, indoor and outdoor PM{sub 2.5} concentrations (69.5, 68.5 and 68.1 {mu}g m{sup -3}, respectively) were found. However, for coarse particles (calculated as the difference between measured PM{sub 10} and PM{sub 2.5}, PM{sub 2.5-10}) indoor and outdoor levels (35.4 and 47.4 {mu}g m{sup -3}) were lower than their corresponding personal exposures (76.3 {mu}g m{sup -3}). Indoor and outdoor NO{sub 2} concentrations were comparable (35.8 and 36.9 ppb) and higher than personal exposures (25.9 ppb). Very low ambient indoor and personal O{sub 3} levels were found, which were mostly below the method's limit of detection (LOD). Outdoor particles contributed significantly to indoor concentrations, with effective penetration efficiencies of 0.61 and 0.30 for PM{sub 2.5} and PM{sub 2.5-10}, respectively. Personal exposures were strongly associated with indoor and outdoor concentrations for PM{sub 2.5}, but weakly associated for PM{sub 2.5-10}. For NO{sub 2}, weak associations were obtained for indoor-outdoor and personal-outdoor relationships. This is probably a result of the presence of gas cooking stoves in all the homes. Median I/O, P/I and P/O ratios for PM{sub 2.5} were close to unity, and for NO{sub 2} they ranged between 0.64 and 0.95. These ratios were probably due to high ambient PM{sub 2.5} and NO{sub 2} levels in Santiago, which diminished the relative contribution of indoor sources and subjects' activities to indoor and personal PM

  20. Current status of programmes to measure and reduce radon exposure in Irish workplaces

    International Nuclear Information System (INIS)

    Colgan, P A; Madden, J S; Synnott, H; Fennell, S; Pollard, D; Fenton, D

    2004-01-01

    National legislation, which implements European Council Directive 96/29/EURATOM in Ireland, sets a reference level of 400 Bq m -3 averaged over any 3 month period for radon exposure in the workplace and also empowers the Radiological Protection Institute of Ireland to direct employers to have radon measurements carried out. This legislation came into effect in May 2000. Radon measurements have already been completed in show caves and other underground workplaces. Between 1998 and 2001, over 33 800 individual radon measurements were carried out in all ground floor offices and classrooms in 3444 schools nationwide as part of a programme undertaken jointly with the Department of Education and Science. Where the average indoor radon concentration in one or more rooms exceeded 200 Bq m -3 , remedial measures were implemented. For concentrations up to 400 Bq m -3 this involved increased ventilation while for higher concentrations an active sump was normally installed. The results of the survey, as well as the effectiveness of the different remedial strategies, are discussed. In the case of other above ground workplaces, different approaches have been adopted. As a first step, workplaces in two known high radon areas were directed to have radon measurements carried out. This programme had limited success because of problems in obtaining accurate workplace databases and a general lack of awareness on the part of employers of the issues involved. From a sample of 2610 employers directed to measure radon, only 408 actually completed measurements and 37 workplaces were identified as having average 3 month average radon concentrations above 400 Bq m -3 . A total of 1356 employers ignored all correspondence, some of which was sent by registered post and signed for on receipt. Current initiatives are focused on the provision of information and include newspaper advertising as well as publications aimed specifically at both employer and employee representative groups. The ability

  1. [Second-hand smoke exposure in hospitality venues in Barcelona: measurement of respirable particles].

    Science.gov (United States)

    Villarroel, Nazmy; López, María José; Sánchez-Martínez, Francesca; Fernández, Esteve; Nebot, Manel

    2011-01-01

    To quantify the concentration of respirable particles equal to or smaller than 2.5μm (PM(2.5)) as a marker of second-hand smoke (SHS) exposure in a sample of hospitality venues in Barcelona 2 years after the Spanish smoking law came into effect. We performed a cross-sectional descriptive study from October to December 2007. The study population consisted of 40 hospitality venues in Barcelona selected by a random route sampling, with representation of the different types of smoking regulation included in the law (smoking allowed, smoking ban and venues with smoking areas). SHS levels were quantified by measuring PM(2.5) concentrations, which were measured using a laser photometer (Side Pack AM 510 Personal Aerosol Monitor). The measurements were carried out for 5 minutes outside the venue and for 30 minutes inside the venue. In addition, observational variables related to the characteristics of the venue and signs of tobacco consumption were recorded. The concentration of PM(2.5) in venues where smoking was still allowed was five times higher than that in venues where smoking was banned (182μg/m(3) and 34μg/m(3), respectively) and exceeded the concentration established by the US Environmental Protection Agency (EPA) as harmful (35μg/m(3)). However, in venues where smoking was banned, the concentration was lower than the EPA standard and there were no significant differences with the outdoor PM(2.5) concentration. Two years after the introduction of the Spanish smoking law, SHS exposure in venues where smoking was allowed was q still very high, representing a significant health risk for hospitality workers. Copyright © 2010 SESPAS. Published by Elsevier Espana. All rights reserved.

  2. Measurements of surgeons' exposure to ionizing radiation dose during intraoperative use of C-arm fluoroscopy.

    Science.gov (United States)

    Lee, Kisung; Lee, Kyoung Min; Park, Moon Seok; Lee, Boram; Kwon, Dae Gyu; Chung, Chin Youb

    2012-06-15

    Measurement of radiation dose from C-arm fluoroscopy during a simulated intraoperative use in spine surgery. OBJECTIVE.: To investigate scatter radiation doses to specific organs of surgeons during intraoperative use of C-arm fluoroscopy in spine surgery and to provide practical intraoperative guidelines. There have been studies that reported the radiation dose of C-arm fluoroscopy in various procedures. However, radiation doses to surgeons' specific organs during spine surgery have not been sufficiently examined, and the practical intraoperative radioprotective guidelines have not been suggested. Scatter radiation dose (air kerma rate) was measured during the use of a C-arm on an anthropomorphic chest phantom on an operating table. Then, a whole body anthropomorphic phantom was located besides the chest phantom to simulate a surgeon, and scatter radiation doses to specific organs (eye, thyroid, breast, and gonads) and direct radiation dose to the surgeon's hand were measured using 4 C-arm configurations (standard, inverted, translateral, and tube translateral). The effects of rotating the surgeon's head away from the patient and of a thyroid shield were also evaluated. Scatter radiation doses decreased as distance from the patient increased during C-arm fluoroscopy use. The standard and translateral C-arm configurations caused lower scatter doses to sensitive organs than inverted and tube translateral configurations. Scatter doses were highest for breast and lowest for gonads. The use of a thyroid shield and rotating the surgeon's head away from the patient reduced scatter radiation dose to the surgeon's thyroid and eyes. The direct radiation dose was at least 20 times greater than scatter doses to sensitive organs. The following factors could reduce radiation exposure during intraoperative use of C-arm; (1) distance from the patient, (2) C-arm configuration, (3) radioprotective equipments, (4) rotating the surgeons' eyes away from the patient, and (5) avoiding

  3. Measurement of exposure buildup factors: The influence of scattered photons on gamma-ray attenuation coefficients

    Science.gov (United States)

    Mann, Kulwinder Singh

    2018-01-01

    Scattered photon's influence on measured values of attenuation coefficients (μm, cm2g-1) for six low-Z (effective atomic number) building materials, at three photon energies has been estimated. Narrow-beam transmission geometry has been used for the measurements. Samples of commonly used engineering materials (Cements, Clay, Lime-Stone, Plaster of Paris) have been selected for the present study. Standard radioactive sources Cs137 and Co60 have been used for obtaining γ-ray energies 661.66, 1173.24 and 1332.50 keV. The optical thickness (OT) of 0.5 mfp (mean free path) has been found the optimum optical thickness (OOT) for μm-measurement in the selected energy range (661.66-1332.50 keV). The aim of this investigation is to provide neglected information regarding subsistence of scattered photons in narrow beam geometry measurements for low-Z materials. The measurements have been performed for a wide range of sample-thickness (2-26 cm) such that their OT varies between 0.2-3.5 mfp in selected energy range. A computer program (GRIC2-toolkit) has been used for various theoretical computations required in this investigation. It has been concluded that in selected energy-range, good accuracy in μm-measurement of low-Z materials can be achieved by keeping their sample's OT below 0.5 mfp. The exposure buildup factors have been measured with the help of mathematical-model developed in this investigation.

  4. Study on the measurements and evaluation of environmental external exposure after a nuclear accident

    International Nuclear Information System (INIS)

    Sakamoto, R.; Saito, K.; Tsutsumi, M.

    2001-01-01

    Several important issues which affect external exposure in contaminated Chernobyl areas have been investigated using field measurements and computational simulations since 1992. The objectives of the study were: 1) the development of a mobile survey method to collect radiation data over the contaminated wide areas in a shot time; 2) the verification of a method to infer external dose to the population; 3) the provision of basic data used for evaluation of external dose due to gamma ray using a Monte Carlo simulation method. To develop a method to rapidly measure radiation over wide areas and map the extend of fallout, a mobile survey system was constructed and tested; the conversion factors to convert the measured data to required quantities were examined; and finally a detailed contamination map was created. The field surveys were implemented by using a land rover and a helicopter. To infer external dose to inhabitants, radiation measurements were carried out in the living environments using accurate dose meters in addition to individual dose measurements using glass dosimeters. Individual doses were inferred from occupancy factors and dose rate data measured with portable dose rate meters in and around houses. The evaluated doses were compared to directly measured individual doses with glass dosimeters in the seven settlements. A good agreement was observed with an error margin of approximate 20%. Basic data used for the evaluation of environmental gamma-ray dose rate were calculated using a Monte Carlo method. The following two kinds of data have been provided from the calculation: a) conversion factors from the nuclide concentration in the ground to the air kerma rate at 1 m height; and b) shielding factors of a typical Chernobyl house for gamma radiation. (M. Suetake)

  5. National campaign of measurement of domestic exposure to radon IPSN-DGS

    International Nuclear Information System (INIS)

    Gailliez, E.

    2000-10-01

    The radon atlas in accommodation, published by the Institute of Nuclear Protection and Safety (I.P.S.N.) and the General Direction of Health (D.G.S.), and available from http://www.ipsn.fr, presents maps and statistical elements from 12 641 measures made in 10013 communes, from 1982 up to and including 1999. The objective pursued is to estimate in an overall way the French population exposure to domestic radon. An update is planned regularly (every two years). In its present version, the modesty of the measures number and the local strong disparities make very difficult the identification of risk areas at the communal level: high voluminal activities can be noticed in any commune; whereas a housing situated in a commune classified in the highest group will not show inescapably a strong concentration in radon leading to take rapid measures. The average value of radon voluminal activity measured in France is 90 Bq. by m 3 . For the risk management, the authorities have kept the value of 400 Bq. by m 3 as caution objective and this one of 1000 Bq. by m 3 as alert threshold, in yearly average value. (N.C.)

  6. Recommendations for Guidelines for EMF Personal Exposure Measurements, Rapid Project #4

    Energy Technology Data Exchange (ETDEWEB)

    T. Dan Bracken, Inc.

    1997-08-01

    The purpose of developing guidelines for electric and magnetic field (EMF) personal exposure measurements (lF'EM) is to ensure reliable and comparable data across I?EM studies. Study techniques may vary due to different populations or objectives, but the resulting data should be consistently reported and comparable, to the extent possible. Any guideline must allow creativity by the research-oriented investigator and provide specific guidance to industrial hygienists or other results-oriented investigators, requiring a standard protocol. Recognizing measurement studies with different purposes is an important aspect of these recommendations. The guidelines presented here intend to produce comparable data across studies while remaining flexible. The recommendations for designing and implementing an EMF PEM program describe a three-stage process. The first step is to clearly state the purpose of the PEM program. The next stage addresses the fundamental elements of an EMF PEM study, including an assessment of the scientific and organizational resources that will be required. This process is codified in a written study plan. These stages are described in 1 Section 5 of this report. The third stage of a PEM study involves the design, implementation and documentation of specific procedures and protocols fo~ sampling strategies, selection of measurement parameters; instrumentation, measurement and data collection, data management, data analysis, quality assurance, uncertainty evaluation, and archiving the study methods and results. The methods for designing these elements of an EMF PEM study are described in Section 6: Specific Guidelines for EMF I?EM Study Design.

  7. Urinary nickel: measurement of exposure by inductively coupled plasma argon emission spectrometry.

    Science.gov (United States)

    Koizumi, Chisato; Usuda, Kan; Hayashi, Satsuki; Dote, Tomotaro; Kono, Koichi

    2004-09-01

    Nickel is a rare earth metal and is widely used in modern industry. Its overexposure in human beings can provoke significant effects including lung, cardiovascular and kidney diseases. As an index of occupational exposure, urine is widely used for the monitoring of nickel concentration because it is a minimally invasive method. Recent studies have used atomic absorption spectrometry to measure nickel concentration. In this study, we introduced novel inductively coupled plasma argon emission spectrometry (ICPAES) which enables us to measure multiple elements simultaneously with smaller volume and with lower detection limits compared to conventional atomic absorption emission spectrometry, and we established the new measuring method by determining the appropriate wavelengths for nickel concentration. Furthermore, using the established new measuring method, we investigated the correlation between a single oral administration of nickel and urine elimination in rats. As a result, different concentrations of nickel standard solutions were measured by ICPAES, and among five specific wavelengths of nickel, 221.647 and 231.604 nm were chosen because they had the highest inclines of both signal to background ratio and emission intensity in simple linear regression analysis. Next, by using healthy human urine samples that had not been exposed to nickel, 231.604 nm was determined to be the most appropriate wavelength because it did not present abnormal intensity due to obstacle wavelength. Male Wistar rats received an oral administration of nickel ranging from 0.025 to 250 mg/kg, which is equivalent to 0.0015 - 15% of LD50, and during the following 24 h, urine samples were collected and the nickel concentration was measured by ICPAES. With a single oral administration of nickel, there was an increase in urine nickel concentration in a dose-dependent manner and the appropriate equation was developed. Acute renal failure was not observed in this dosage of oral nickel

  8. Radiation protection at workplaces with increased natural radiation exposure in Greece: recording, monitoring and protection measures

    International Nuclear Information System (INIS)

    Potiriadis, C.; Koukoliou, V.

    2002-01-01

    Greek Atomic Energy Commission (GAEC) is the regulatory, advisory and competent authority on radiation protection matters. It is the authority responsible for the introduction of Radiation Protection regulations and monitoring of their implementation. In 1997, within the frame of its responsibilities the Board of the GAEC appointed a task group of experts to revise and bring the present Radiation Protection Regulations into line with the Basic Safety Standards (BSS) 96/29/Euratom Directive and the 97/43/Euratom Directive (on health protection of individuals against the dangers of ionising radiation in relation to medical exposure). Concerning the Title 7. of the new European BSS Directive, which refers to the Radiation Protection at work places with increased levels of natural radiation exposure, the Radiation Protection Regulations provides that the authority responsible for recording, monitoring and introducing protection measures at these places is the GAEC. Practices where effective doses to the workers due to increased natural radiation levels, may exceed 1mSv/y, have to be specified and authorised by the GAEC. The identification procedure is ongoing

  9. Organic solvent topical report

    Energy Technology Data Exchange (ETDEWEB)

    COWLEY, W.L.

    1999-05-13

    This report provides the basis for closing the organic solvent safety issue. Sufficient information is presented to conclude that risk posed by an organic solvent fire is within risk evaluation guidelines. This report updates information contained in Analysis of Consequences of Postulated Solvent Fires in Hanford Site Waste Tanks. WHC-SD-WM-CN-032. Rev. 0A (Cowley et al. 1996). However, this document will not replace Cowley et al (1996) as the primary reference for the Basis for Interim Operation (BIO) until the recently submitted BIO amendment (Hanson 1999) is approved by the US Department of Energy. This conclusion depends on the use of controls for preventing vehicle fuel fires and for limiting the use of flame cutting in areas where hot metal can fall on the waste surface.The required controls are given in the Tank Waste Remediation System Technical Safety Requirements (Noorani 1997b). This is a significant change from the conclusions presented in Revision 0 of this report. Revision 0 of this calcnote concluded that some organic solvent fire scenarios exceeded risk evaluation guidelines, even with controls imposed.

  10. Organic solvent topical report

    Energy Technology Data Exchange (ETDEWEB)

    Cowley, W.L.

    1998-04-30

    This report is the technical basis for the accident and consequence analyses used in the Hanford Tank Farms Basis for Interim Operation. The report also contains the scientific and engineering information and reference material needed to understand the organic solvent safety issue. This report includes comments received from the Chemical Reactions Subcommittee of the Tank Advisory Panel.

  11. Organic solvent topical report

    International Nuclear Information System (INIS)

    COWLEY, W.L.

    1999-01-01

    This report provides the basis for closing the organic solvent safety issue. Sufficient information is presented to conclude that risk posed by an organic solvent fire is within risk evaluation guidelines. This report updates information contained in Analysis of Consequences of Postulated Solvent Fires in Hanford Site Waste Tanks. WHC-SD-WM-CN-032. Rev. 0A (Cowley et al. 1996). However, this document will not replace Cowley et al (1996) as the primary reference for the Basis for Interim Operation (BIO) until the recently submitted BIO amendment (Hanson 1999) is approved by the US Department of Energy. This conclusion depends on the use of controls for preventing vehicle fuel fires and for limiting the use of flame cutting in areas where hot metal can fall on the waste surface.The required controls are given in the Tank Waste Remediation System Technical Safety Requirements (Noorani 1997b). This is a significant change from the conclusions presented in Revision 0 of this report. Revision 0 of this calcnote concluded that some organic solvent fire scenarios exceeded risk evaluation guidelines, even with controls imposed

  12. Organic solvent topical report

    International Nuclear Information System (INIS)

    Cowley, W.L.

    1998-01-01

    This report is the technical basis for the accident and consequence analyses used in the Hanford Tank Farms Basis for Interim Operation. The report also contains the scientific and engineering information and reference material needed to understand the organic solvent safety issue. This report includes comments received from the Chemical Reactions Subcommittee of the Tank Advisory Panel

  13. DESIGNING GREENER SOLVENTS

    Science.gov (United States)

    Computer-aided design of chemicals and chemical mixtures provides a powerful tool to help engineers identify cleaner process designs and more-benign alternatives to toxic industrial solvents. Three software programs are discussed: (1) PARIS II (Program for Assisting the Replaceme...

  14. Measuring personal exposure from 900MHz mobile phone base stations in Australia and Belgium using a novel personal distributed exposimeter.

    Science.gov (United States)

    Bhatt, Chhavi Raj; Thielens, Arno; Redmayne, Mary; Abramson, Michael J; Billah, Baki; Sim, Malcolm R; Vermeulen, Roel; Martens, Luc; Joseph, Wout; Benke, Geza

    2016-01-01

    The aims of this study were to: i) measure personal exposure in the Global System for Mobile communications (GSM) 900MHz downlink (DL) frequency band with two systems of exposimeters, a personal distributed exposimeter (PDE) and a pair of ExpoM-RFs, ii) compare the GSM 900MHz DL exposures across various microenvironments in Australia and Belgium, and iii) evaluate the correlation between the PDE and ExpoM-RFs measurements. Personal exposure data were collected using the PDE and two ExpoM-RFs simultaneously across 34 microenvironments (17 each in Australia and Belgium) located in urban, suburban and rural areas. Summary statistics of the electric field strengths (V/m) were computed and compared across similar microenvironments in Australia and Belgium. The personal exposures across urban microenvironments were higher than those in the rural or suburban microenvironments. Likewise, the exposure levels across the outdoor were higher than those for indoor microenvironments. The five highest median exposure levels were: city centre (0.248V/m), bus (0.124V/m), railway station (0.105V/m), mountain/forest (rural) (0.057V/m), and train (0.055V/m) [Australia]; and bicycle (urban) (0.238V/m), tram station (0.238V/m), city centre (0.156V/m), residential outdoor (urban) (0.139V/m) and park (0.124V/m) [Belgium]. Exposures in the GSM900 MHz frequency band across most of the microenvironments in Australia were significantly lower than the exposures across the microenvironments in Belgium. Overall correlations between the PDE and the ExpoM-RFs measurements were high. The measured exposure levels were far below the general public reference levels recommended in the guidelines of the ICNIRP and the ARPANSA. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. In-vivo measurements of Pb-210 to determine cumulative exposure to radon daughters: A pilot study

    International Nuclear Information System (INIS)

    Laurer, G.R.; Cohen, N.; Stark, A.; Ju, C.

    1991-05-01

    The objective of this study is to demonstrate the feasibility of estimating cumulative exposure of individuals to low concentrations of radon by measuring the amount of Pb-A-10 in their skeletons. This report presents progress to date establishing the validity of an vivo technique to measure skeletal burdens of Pb-210, accumulated from exposure to radon and radon progeny. With the skeletal content of Pb--210 and a model for Pb metabolism, cumulative exposure to radon and its short-lived daughters (radon/daughters) may be calculated for use in deriving a dose-response relationship between lung cancer and exposure to radon/daughters. Data are presented for 29 subjects exposed to ''above-average'' radon concentrations in their homes, showing the correlation between measured Pb--210 burdens, and measured pCi/l and WLM exposure estimates. Their results are compared to measurements of a population of 24 subject's presumed exposed to average concentrations. Measurements of a Pennsylvania family exposed for a year in a home with an extremely high radon content are also presented. Update of results of an ongoing study of the biological half-time of Pb--210 in man involving measurements, of a retired radiation worker with a 40 year old skeletal burden of Pb-210

  16. An exposure system for measuring nasal and lung uptake of vapors in rats

    Energy Technology Data Exchange (ETDEWEB)

    Dahl, A.R.; Brookins, L.K.; Gerde, P. [National Inst. for Working Life, Solna (Sweden)

    1995-12-01

    Inhaled gases and vapors often produce biological damage in the nasal cavity and lower respiratory tract. The specific site within the respirator tract at which a gas or vapor is absorbed strongly influences the tissues at risk to potential toxic effects; to predict or to explain tissue or cell specific toxicity of inhaled gases or vapors, the sites at which they are absorbed must be known. The purpose of the work reported here was to develop a system for determining nose and lung absorption of vapors in rats, an animal commonly used in inhalation toxicity studies. In summary, the exposure system described allows us to measure in the rate: (1) nasal absorption and desorption of vapors; (2) net lung uptake of vapors; and (3) the effects of changed breathing parameters on vapor uptake.

  17. Measuring radiation exposure during percutaneous drainages: can shoulder dosemeters be used to estimate finger doses?

    International Nuclear Information System (INIS)

    Vehmas, Tapio; Tikkanen, Heikki

    1992-01-01

    To assess the need for extra finger dosemeters, radiologists' and assistants' radiation exposure at both shoulders and at the third fingers of both hands were recorded using thermoluminescent dosemeters during 27 interventional drainage procedures. Under couch screening was used. Mean dose rates were calculated by dividing dose by screening time. The radiologists' bilateral finger dose rates did not correlate with each other; nor did dose rates between the left shoulder and the right hand. The radiologists' dose rates at both shoulders, correlated with each other, as did shoulder dose rates with dose rates at the ispilateral hand. The right shoulder dose rates correlated with the left hand dose rates. The assistants' dose rates at places of measurement showed significant correlations with each other. (Author)

  18. Measurement of exposures to radioactivity and monitoring of effects on health

    International Nuclear Information System (INIS)

    Spira, Alfred; Boutou, Odile

    1999-01-01

    On the request of the French ministries of Health and of the Environment, the author reports thoughts and proposals regarding epidemiological problems related to natural and artificial radioactive emissions. He first reports an analysis of the present context (assessment of health risks, ionizing radiation in France, radiation protection, nuclear operators, relationship between ionizing radiation and health, epidemiology) and knowledge (about nuclear and health, available results, current investigations). He outlines the benefits of an epidemiological monitoring and its requirements, and identifies the various components of this monitoring. While presenting current works, biological and epidemiological studies performed in the northern Cotentin area, he makes some specific proposals for this area and notably for the workers of La Hague. He proposes the implementation of a national arrangement comprising a measurement of exposures, an epidemiological monitoring, and a sociological survey. He discusses the associated administrative organisation and needs

  19. Baseline repeated measures from controlled human exposure studies: associations between ambient air pollution exposure and the systemic inflammatory biomarkers IL-6 and fibrinogen.

    Science.gov (United States)

    Thompson, Aaron M S; Zanobetti, Antonella; Silverman, Frances; Schwartz, Joel; Coull, Brent; Urch, Bruce; Speck, Mary; Brook, Jeffrey R; Manno, Michael; Gold, Diane R

    2010-01-01

    Systemic inflammation may be one of the mechanisms mediating the association between ambient air pollution and cardiovascular morbidity and mortality. Interleukin-6 (IL-6) and fibrinogen are biomarkers of systemic inflammation that are independent risk factors for cardio-vascular disease. We investigated the association between ambient air pollution and systemic inflammation using baseline measurements of IL-6 and fibrinogen from controlled human exposure studies. In this retrospective analysis we used repeated-measures data in 45 nonsmoking subjects. Hourly and daily moving averages were calculated for ozone, nitrogen dioxide, sulfur dioxide, and particulate matter pollutants on systemic IL-6 and fibrinogen. Effect modification by season was considered. We observed a positive association between IL-6 and O3 [0.31 SD per O3 interquartile range (IQR); 95% confidence interval (CI), 0.080.54] and between IL-6 and SO2 (0.25 SD per SO2 IQR; 95% CI, 0.060.43). We observed the strongest effects using 4-day moving averages. Responses to pollutants varied by season and tended to be higher in the summer, particularly for O3 and PM2.5. Fibrinogen was not associated with pollution. This study demonstrates a significant association between ambient pollutant levels and baseline levels of systemic IL-6. These findings have potential implications for controlled human exposure studies. Future research should consider whether ambient pollution exposure before chamber exposure modifies IL-6 response.

  20. Commentary: variability in workplace exposures and the design of efficient measurement and control strategies

    NARCIS (Netherlands)

    A. Burdorf (Alex); M. van Tongeren

    2003-01-01

    textabstractKromhout et al.'s (1993) well-cited publication presented detailed information on statistical procedures to estimate the magnitude of exposure variability within and between workers, drawing from a large database on chemical exposures throughout industry. It

  1. Conjunctival Ultraviolet Autofluorescence as a Measure of Past Sun Exposure in Children.

    Science.gov (United States)

    Sun, Cong; Pezic, Angela; Mackey, David A; Carlin, John B; Kemp, Andrew; Ellis, Justine A; Cameron, Fergus J; Rodda, Christine P; Dwyer, Terence; Coroneo, Minas T; Ponsonby, Anne-Louise

    2017-07-01

    Background: Conjunctival ultraviolet autofluorescence (CUVAF) area detected from UVAF photographs is a recently developed potential marker for past sun exposure, but its relationship with sun-related factors has not been fully investigated. Methods: The study included 339 healthy children ages 5 to 15 years in Melbourne, Australia. Data were collected by questionnaire and examination at school. CUVAF area was measured using a computer program and analyzed as a continuous and dichotomous outcome (any/none). Results: Fifty-three children (15.6%) had detectable CUVAF, and the youngest age at which a child showed sun damage was 8 years. Compared with silicone skin cast score, there was good inter-grader agreement on CUVAF grading, with Cohen kappa 0.85 [95% confidence interval (CI), 0.65-1.00] for total CUVAF area using both eye photographs. Perfect intra-grader agreement was achieved. Fairer pigmentation, including medium/fair skin color [adjusted odds ratio (AOR), 3.42; 95% CI, 1.02-11.48 vs. dark/olive] and blue/gray eye color (AOR, 4.07; 95% CI, 1.73-9.55 vs. brown) was associated with increased odds of CUVAF. Increasing lifetime sunburn number (e.g., AOR, 2.89; 95% CI, 1.14-7.35 and 4.29; 1.04-17.76 for sunburns 2 to 4 and ≥ 5 times, respectively, vs. no sunburns, trend P = 0.004) and freckling by the end of last summer were associated with increased odds of CUVAF. Conclusions: CUVAF area can be an a priori objective measure of past sun exposure in pediatric populations for future research. Impact: To our knowledge, this is the first pediatric study that evaluated associations of sun-related risk factors with CUVAF. Cancer Epidemiol Biomarkers Prev; 26(7); 1146-53. ©2017 AACR . ©2017 American Association for Cancer Research.

  2. [Effects of subliminal mere exposure to group members on intergroup evaluation: category evaluation measured in the Implicit Association Test (IAT)].

    Science.gov (United States)

    Kawakami, Naoaki; Yoshida, Fujio

    2010-10-01

    This study investigated the effects of subliminal mere exposure to ingroup or outgroup members on intergroup evaluation as measured in the Implicit Association Test (IAT). Participants first memorized the members of two groups. Then, they were assigned to either group by lot, and completed the IAT for intergroup evaluation (Time 1). In the next phase, half the participants were subliminally exposed to ingroup members and half to outgroup members. Upon completion of the exposure, the same IAT was administered at Time 2. The results showed that participants who were exposed to ingroup members evaluated the ingroup more positively at Time 2 than at Time 1. Participants who were exposed to outgroup members did not show an effect toward the outgroup. The finding that the mere exposure effect occurred only for the ingroup exposure condition suggests that unconscious awareness of the ingroup enhances the mere exposure effect.

  3. Head impact exposure measured in a single youth football team during practice drills.

    Science.gov (United States)

    Kelley, Mireille E; Kane, Joeline M; Espeland, Mark A; Miller, Logan E; Powers, Alexander K; Stitzel, Joel D; Urban, Jillian E

    2017-11-01

    OBJECTIVE This study evaluated the frequency, magnitude, and location of head impacts in practice drills within a youth football team to determine how head impact exposure varies among different types of drills. METHODS On-field head impact data were collected from athletes participating in a youth football team for a single season. Each athlete wore a helmet instrumented with a Head Impact Telemetry (HIT) System head acceleration measurement device during all preseason, regular season, and playoff practices. Video was recorded for all practices, and video analysis was performed to verify head impacts and assign each head impact to a specific drill. Eleven drills were identified: dummy/sled tackling, install, special teams, Oklahoma, one-on-one, open-field tackling, passing, position skill work, multiplayer tackle, scrimmage, and tackling drill stations. Generalized linear models were fitted to log-transformed data, and Wald tests were used to assess differences in head accelerations and impact rates. RESULTS A total of 2125 impacts were measured during 30 contact practices in 9 athletes (mean age 11.1 ± 0.6 years, mean mass 44.9 ± 4.1 kg). Open-field tackling had the highest median and 95th percentile linear accelerations (24.7 g and 97.8 g, respectively) and resulted in significantly higher mean head accelerations than several other drills. The multiplayer tackle drill resulted in the highest head impact frequency, with an average of 0.59 impacts per minute per athlete, but the lowest 95th percentile linear accelerations of all drills. The front of the head was the most common impact location for all drills except dummy/sled tackling. CONCLUSIONS Head impact exposure varies significantly in youth football practice drills, with several drills exposing athletes to high-magnitude and/or high-frequency head impacts. These data suggest that further study of practice drills is an important step in developing evidence-based recommendations for modifying or eliminating

  4. Influence of race on prenatal phthalate exposure and anogenital measurements among boys and girls.

    Science.gov (United States)

    Wenzel, Abby G; Bloom, Michael S; Butts, Celeste D; Wineland, Rebecca J; Brock, John W; Cruze, Lori; Unal, Elizabeth R; Kucklick, John R; Somerville, Stephen E; Newman, Roger B

    2018-01-01

    Select phthalates have antiandrogenic activity, which raises concern for adverse developmental outcomes given widespread exposure of pregnant women. Investigators have reported associations between maternal urinary phthalates and altered anogenital distance (AGD), a marker of in utero androgen activity, among offspring. However, data assessing the impact of race on these associations is sparse. To evaluate associations between prenatal phthalate exposure and AGD in a racially diverse newborn population. We prospectively collected second trimester urine from 187 African American and 193 white mothers, and used liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) to measure eight phthalate metabolites and calculate molar sums. We measured anopenile (APD) and anoscrotal (ASD) distances of 171 boys and anoclitoral (ACD) and anofourchette (AFD) distances of 128 girls at delivery. We collected sociodemographic and clinical data from questionnaires and delivery records. We identified a statistically significant inverse association for mono-2-ethylhexyl phthalate (MEHP) and APD in boys (B=-1.57mm, p=0.02), which was stronger for African Americans (B=-2.07mm, p=0.04) than for whites (B=-1.23mm, p=0.22), although the racial interaction was not statistically significant (p=0.56). We found a longer ASD for higher molar sums of dibutyl phthalate (∑DBP; B=0.99mm, p=0.04), with stronger associations for whites (B=1.30mm, p=0.04) than for African Americans (B=0.39mm, p=0.59), again without a statistically significant racial interaction (p=0.34). Among girls, we found inverse associations for tertiles of MEHP with AFD and ACD, and statistically significant race-based interactions, in which ACD was longer for whites and shorter for African Americans, following exposure to monoethyl phthalate (MEP; p=0.01) and ∑DBP (p=0.08). Our findings suggest race and sex play important roles in phthalate-associated reproductive developmental toxicity, with important

  5. Risk of whole body radiation exposure and protective measures in fluoroscopically guided interventional techniques: a prospective evaluation

    Directory of Open Access Journals (Sweden)

    Rivera Jose

    2003-08-01

    REM per procedure. In Group III the scatter radiation exposure was 1152 mREM with 1.3930 mREM per procedure. Conclusion Results of this study showed that scatter radiation exposure to both the upper and lower parts of the physician's body is present. Protection was offered by traditional measures to the upper body only.

  6. Food environments and dietary intakes among adults: does the type of spatial exposure measurement matter? A systematic review.

    Science.gov (United States)

    Bivoltsis, Alexia; Cervigni, Eleanor; Trapp, Gina; Knuiman, Matthew; Hooper, Paula; Ambrosini, Gina Leslie

    2018-06-09

    The relationships between food environments and dietary intake have been assessed via a range of methodologically diverse measures of spatial exposure to food outlets, resulting in a largely inconclusive body of evidence, limiting informed policy intervention. This systematic review aims to evaluate the influence of methodological choice on study outcomes by examining the within-study effect of availability (e.g., counts) versus accessibility (e.g., proximity) spatial exposure measures on associations with diet. (PROSPERO registration: CRD42018085250). PubMed, Web of Science, Scopus and ScienceDirect databases were searched for empirical studies from 1980 to 2017, in the English language, involving adults and reporting on the statistical association between a dietary outcome and spatial exposure measures of both availability and accessibility. Studies were appraised using an eight-point quality criteria with a narrative synthesis of results. A total of 205 associations and 44 relationships (i.e., multiple measures of spatial exposure relating to a particular food outlet type and dietary outcome) were extracted from 14 eligible articles. Comparative measures were dominated by counts (availability) and proximity (accessibility). Few studies compared more complex measures and all counts were derived from place-based measures of exposure. Sixteen of the 44 relationships had a significant effect involving an availability measure whilst only 8 had a significant effect from an accessibility measure. The largest effect sizes in relationships were mostly for availability measures. After stratification by scale, availability measure had the greatest effect size in 139 of the 176 pairwise comparisons. Of the 33% (68/205) of associations that reached significance, 53/68 (78%) were from availability measures. There was no relationship between study quality and reported study outcomes. The limited evidence suggests that availability measures may produce significant and greater

  7. Permeability of commercial solvents through living human skin

    DEFF Research Database (Denmark)

    Ursin, C; Hansen, C M; Van Dyk, J W

    1995-01-01

    A procedure has been developed for measuring the steady state rate of permeation of commercial solvents through living human skin. To get the most consistent results, it was necessary with some solvents to normalize the solvent permeation rate of a given skin sample with its [3H]water permeation...... rate. For other solvents this was not necessary, so the un-normalized data were used. High [3H]water permeation rate also was used as a criterion for "defective" skin samples that gave erroneous permeability rates, especially for solvents having slow permeability. The linearity of the steady state data...... was characterized by calculation of the "percent error of the slope." The following permeability rates (g/m2h) of single solvents were measured: dimethyl sulfoxide (DMSO), 176; N-methyl-2-pyrrolidone, 171; dimethyl acetamide, 107; methyl ethyl ketone, 53; methylene chloride, 24; [3H]water, 14.8; ethanol, 11...

  8. Solubility of daidzin in different organic solvents and (ethyl alcohol + water) mixed solvents

    International Nuclear Information System (INIS)

    Fan, Jie-Ping; Yang, Dan; Xu, Xiao-Kang; Guo, Xiao-Jie; Zhang, Xue-Hong

    2015-01-01

    Highlights: • The solubilities of daidzin were measured in various solvents. • The solubility data were correlated by three models. • The thermodynamic properties of the dissolution process were also determined. - Abstract: The solubility of daidzin in different organic solvents and (ethyl alcohol + water) mixed solvents was measured by high performance liquid chromatography (HPLC) analysis method from T = (283.2 to 323.2) K at atmosphere pressure. The results show that at higher temperature more daidzin dissolves, and moreover, the solubility increases with the ethyl alcohol mole fraction increase in the (ethyl alcohol + water) mixed solvents. The experimental solubility values were correlated by a simplified thermodynamic equation, λh equation and modified Apelblat equation. Based on the solubility of daidzin, the enthalpy and entropy of solution were also evaluated by van’t Hoff equation. The results illustrated that the dissolution process of daidzin is endothermic and entropy driven

  9. Assessment of uncertainty associated with measuring exposure to radon and decay products in the French uranium miners cohort

    International Nuclear Information System (INIS)

    Allodji, Rodrigue S; Leuraud, Klervi; Laurier, Dominique; Bernhard, Sylvain; Henry, Stéphane; Bénichou, Jacques

    2012-01-01

    The reliability of exposure data directly affects the reliability of the risk estimates derived from epidemiological studies. Measurement uncertainty must be known and understood before it can be corrected. The literature on occupational exposure to radon ( 222 Rn) and its decay products reveals only a few epidemiological studies in which uncertainty has been accounted for explicitly. This work examined the sources, nature, distribution and magnitude of uncertainty of the exposure of French uranium miners to radon ( 222 Rn) and its decay products. We estimated the total size of uncertainty for this exposure with the root sum square (RSS) method, which may be an alternative when repeated measures are not available. As a result, we identified six main sources of uncertainty. The total size of the uncertainty decreased from about 47% in the period 1956–1974 to 10% after 1982, illustrating the improvement in the radiological monitoring system over time.

  10. [Occupational exposure investigation and protective measures in a tertiary infectious disease hospital].

    Science.gov (United States)

    Ding, H M; Zhou, X P; Huang, J Z

    2018-02-20

    Objective: To investigate the cause of occupational exposure among 136 nurses in a tertiary infectious disease hospital, and puts forward the prevention strategy. Methods: A total of 136 nurses exposed to occupational exposure between 2014 and 2016 were included in the study. Analysis was conducted from the years of work of nurses, exposure routes, and the pathogens. Results: The nurses suffer from the highest risk of occupational exposures (73.91%) .Nurses working for less than 5 years and interns are most likely to suffer occupational exposure (45.59% and 35.29% respectively) . Occupational exposure was mainly caused by needle injuries, in which infusion was the main route of occupational exposure (36.76%) . The improper treatment of needle pulling after infusion is the main link of needle puncture (36.76%) . Occupational exposure pathogens were mainly HBV (63.24%) . Conclusion: Nursing staff is the high-risk group of occupational exposure. Irregular operation, lack of awareness of protection, improper disposal after the needle withdrawal and poor safety assessment of the operating environment are the main causes of occupational exposure. It is suggested to strengthen the training of occupational safety and protection, enhance clinical nurses occupational safety protection consciousness, standardize medical operation, so as to prevent the occurrence of occupational exposure.

  11. Current status of programmes to measure and reduce radon exposure in Irish workplaces

    Energy Technology Data Exchange (ETDEWEB)

    Colgan, P A; Madden, J S; Synnott, H; Fennell, S; Pollard, D; Fenton, D [Radiological Protection Institute of Ireland, 3 Clonskeagh Square, Dublin 14(Ireland)

    2004-06-01

    National legislation, which implements European Council Directive 96/29/EURATOM in Ireland, sets a reference level of 400 Bq m{sup -3} averaged over any 3 month period for radon exposure in the workplace and also empowers the Radiological Protection Institute of Ireland to direct employers to have radon measurements carried out. This legislation came into effect in May 2000. Radon measurements have already been completed in show caves and other underground workplaces. Between 1998 and 2001, over 33 800 individual radon measurements were carried out in all ground floor offices and classrooms in 3444 schools nationwide as part of a programme undertaken jointly with the Department of Education and Science. Where the average indoor radon concentration in one or more rooms exceeded 200 Bq m{sup -3}, remedial measures were implemented. For concentrations up to 400 Bq m{sup -3} this involved increased ventilation while for higher concentrations an active sump was normally installed. The results of the survey, as well as the effectiveness of the different remedial strategies, are discussed. In the case of other above ground workplaces, different approaches have been adopted. As a first step, workplaces in two known high radon areas were directed to have radon measurements carried out. This programme had limited success because of problems in obtaining accurate workplace databases and a general lack of awareness on the part of employers of the issues involved. From a sample of 2610 employers directed to measure radon, only 408 actually completed measurements and 37 workplaces were identified as having average 3 month average radon concentrations above 400 Bq m{sup -3}. A total of 1356 employers ignored all correspondence, some of which was sent by registered post and signed for on receipt. Current initiatives are focused on the provision of information and include newspaper advertising as well as publications aimed specifically at both employer and employee representative

  12. Secondhand tobacco smoke exposure and heart rate variability and inflammation among non-smoking construction workers: a repeated measures study.

    Science.gov (United States)

    Zhang, Jinming; Fang, Shona C; Mittleman, Murray A; Christiani, David C; Cavallari, Jennifer M

    2013-10-02

    Although it has been well recognized that exposure to secondhand tobacco smoke (SHS) is associated with cardiovascular mortality, the mechanisms and time course by which SHS exposure may lead to cardiovascular effects are still being explored. Non-smoking workers were recruited from a local union and monitored inside a union hall while exposed to SHS over approximately 6 hours. Participants were fitted with a continuous electrocardiographic monitor upon enrollment which was removed at the end of a 24-hr monitoring period. A repeated measures study design was used where resting ECGs and blood samples were taken from individuals before SHS exposure (baseline), immediately following SHS exposure (post) and the morning following SHS exposure (next-morning).Inflammatory markers, including high sensitivity C-reactive protein (CRP) and white blood cell count (WBC) were analyzed. Heart rate variability (HRV) was analyzed from the ECG recordings in time (SDNN, rMSSD) and frequency (LF, HF) domain parameters over 5-minute periods. SHS exposure was quantified using a personal fine particulate matter (PM2.5) monitor.Linear mixed effects regression models were used to examine within-person changes in inflammatory and HRV parameters across the 3 time periods. Exposure-response relationships with PM2.5 were examined using mixed effects models. All models were adjusted for age, BMI and circadian variation. A total of 32 male non-smokers were monitored between June 2010 and June 2012. The mean PM2.5 from SHS exposure was 132 μg/m3. Immediately following SHS exposure, a 100 μg/m3 increase in PM2.5 was associated with declines in HRV (7.8% [standard error (SE) =3%] SDNN, 8.0% (SE = 3.9%) rMSSD, 17.2% (SE = 6.3%) LF, 29.0% (SE = 10.1%) HF) and increases in WBC count 0.42 (SE = 0.14) k/μl. Eighteen hours following SHS exposure, a 100 μg/m3 increase in PM2.5 was associated with 24.2% higher CRP levels. Our study suggest that short-term SHS exposure is associated

  13. Home outdoor models for traffic-related air pollutants do not represent personal exposure measurements in Southern California

    International Nuclear Information System (INIS)

    Ducret-Stich, R; Gemperli, A; Ineichen, A; Phuleria, H C; Delfino, R J; Tjoa, T; Wu, J; Liu, L-J S

    2009-01-01

    Recent studies have used measurements or estimates of traffic-related air pollutants at home or school locations to link associations between exposure and health. However, little is known about the validity of these outdoor concentrations as an estimate for personal exposure to traffic. This paper compares modelled outdoor concentrations at home with personal exposure to traffic air pollution of 63 children in two areas in Los Angeles in 2003/2004. Exposure monitoring consisted of sixteen 10-day monitoring runs, with each run monitoring 4 subjects concurrently with the active personal DataRAM for particulate matter 25 ), elemental carbon (EC) and organic carbon (OC). One child per run had concurrent indoor/outdoor home monitoring. Measurements at central sites (24-hr PM 25 , EC, OC) were taken daily and concentrations of PM 25 , EC, and OC from traffic sources were calculated using the CALINE4 model for individual residences. We modelled outdoor concentrations of PM 2 5 , EC and OC with multilinear regression including GIS and meteorological parameters and adjusted for auto-correlation between repeated measurements. The model fit (R 2 ) for home outdoor estimates was 0.94, 0.74 and 0.80 for PM 25 , EC and OC, respectively. Comparisons between these outdoor estimates and the personal measurements showed a good agreement for PM 25 (R 2 =0.65-0.70) with a mean bias of -0.7±11.8|ag for the smog receptor area, and 18.9±16.2|ag for the traffic impacted area. However the outdoor estimates were not related to personal exposure for EC (R 2 =0.01-0.29) and OC (R 2 =0.03- 0.14). Conclusions: Predictions of outdoor concentrations can be used as approximations of personal exposure to PM 25 . However, they are not appropriate for estimating personal exposure to traffic-related air pollutants including EC and OC in studies of acute exposure-response relationships.

  14. Improvement in radiation exposure measurements at Rocky Flats over the past 30 years and its possible impact on epidemiological studies

    International Nuclear Information System (INIS)

    Lagerquist, C.R.; Putzier, E.A.

    1983-01-01

    The precision of measuring radaition exposures has steadily improved since the Rocky Flats Plant became operational in 1952. These improvements raise questions for the epidemiologists who are trying to relate possible radiation-induced effects to total radiation exposure. The effect of these changes on total dose is discussed. The practice of estimating systemic depositions of plutonium 3 to 5 times higher than the amounts found at autopsy is also discussed in the context of possible effects on epidemiological studies

  15. Do hunger and exposure to food affect scores on a measure of hedonic hunger? An experimental study.

    Science.gov (United States)

    Witt, Ashley A; Raggio, Greer A; Butryn, Meghan L; Lowe, Michael R

    2014-03-01

    Research suggests that visceral bodily states, such as hunger, can affect participants' responses on self-report measures of eating behavior. The present study evaluated the influence of hunger and exposure to palatable food on self-reported hedonic appetite, measured using the Power of Food Scale (PFS). A secondary aim was to evaluate the effects of these manipulations on self-reported external eating and disinhibition. Participants (N=67) ate a standardized meal followed by a 4-h fast. Participants were randomized to one of four groups (Fasted/Food Absence, Fasted/Food Exposure, Fed/Food Absence, or Fed/Food Exposure). In Phase I of the experiment (Hunger Manipulation), participants randomized to the "Fed" group drank a protein shake, while those in the "Fasted" group did not receive a shake. In Phase II (Palatable Food Exposure), participants in the "Food Exposure" group were visually exposed to palatable food items, while "Food Absence" participants were not. All participants completed the PFS, Dutch Eating Behavior Questionnaire External Eating subscale, and the Disinhibition subscale from the Eating Inventory during Phase II. Results showed no significant main or interactive effects of Hunger condition or Food Exposure condition on PFS, External Eating, or Disinhibition scores (all p'shunger and exposure interventions were successful. Results suggest that relatively short fasting periods (e.g., 4h) analogous to typical breaks between meals are not associated with changes in scores on the PFS, External Eating, or Disinhibition scales. Hedonic hunger, at least as measured by the PFS, may represent a relatively stable construct that is not substantially affected by daily variations in hunger. In addition, individual differences in exposure to food in the immediate environment are unlikely to confound research using these measures. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Solar UV exposure among outdoor workers in Denmark measured with personal UV-B dosimeters: technical and practical feasibility.

    Science.gov (United States)

    Grandahl, Kasper; Mortensen, Ole Steen; Sherman, David Zim; Køster, Brian; Lund, Paul-Anker; Ibler, Kristina Sophie; Eriksen, Paul

    2017-10-10

    Exposure to solar ultraviolet radiation is a well-known cause of skin cancer. This is problematic for outdoor workers. In Denmark alone, occupational skin cancer poses a significant health and safety risk for around 400,000 outdoor workers. Objective measures of solar ultraviolet radiation exposure are needed to help resolve this problem. This can be done using personal ultraviolet radiation dosimeters. We consider technical and practical feasibility of measuring individual solar ultraviolet exposure at work and leisure in professions with different á priori temporal high-level outdoor worktime, using aluminium gallium nitride (AlGaN) photodiode detector based personal UV-B dosimeters. Essential technical specifications including the spectral and angular responsivity of the dosimeters are described and pre-campaign dosimeter calibration applicability is verified. The scale and conduct of dosimeter deployment and campaign in-field measurements including failures and shortcomings affecting overall data collection are presented. Nationwide measurements for more than three hundred and fifty workers from several different professions were collected in the summer of 2016. On average, each worker's exposure was measured for a 2-week period, which included both work and leisure. Data samples of exposure at work during a Midsummer day show differences across professions. A construction worker received high-level occupational UV exposure most of the working day, except during lunch hour, accumulating to 5.1 SED. A postal service worker was exposed intermittently around noon and in the afternoon, preceded by no exposure forenoon when packing mail, accumulating to 1.6 SED. A crane fitter was exposed only during lunch hour, accumulating to 0.7 SED. These findings are in line with our specialist knowledge as occupational physicians. Large-scale use of personal UV-B dosimeters for measurement of solar ultraviolet radiation exposure at work and leisure in Denmark is indeed

  17. Advances in the sample preparation and the detector for a combined solvent extraction-liquid scintillation method of low-level plutonium measurement

    International Nuclear Information System (INIS)

    Perdue, P.T.; Christian, D.J.; Thorngate, J.H.; McDowell, W.J.; Case, G.N.

    1976-07-01

    A combined solvent extraction-liquid scintillation technique, developed at Oak Ridge National Laboratory (ORNL), has many possible applications to the determination of low levels of plutonium and other alpha-emitting nuclides. Using these procedures, plutonium can be extracted from biological or environmental samples and introduced directly into a liquid scintillator. Quenching of the scintillator is thus minimized so that spectroscopic techniques may be employed. Existing chemical procedures and counting equipment were reviewed and improved. Purification of the di(2-ethylhexyl)phosphoric acid (used as the actinide extractant) was found necessary. Destruction of organic material in the sample and control of the valence state of plutonium were found to be major sources of irreproducibility. Methods were developed to allow samples separated with commonly used ion exchange techniques to be extracted into the scintillator. Comparisons were made of a wide variety of the components and parameters of the detector system to find the best combination of pulse-height resolution and pulse-shape discrimination. When a single phototube was used, optimum performance was obtained using a hemispherical reflector-sample holder viewed sideways by an RCA 8575 photomultiplier tube used in conjunction with a special integrating preamplifier and a good quality linear amplifier that used delay lines to shape the pulses

  18. Solvent selection methodology for pharmaceutical processes: Solvent swap

    DEFF Research Database (Denmark)

    Papadakis, Emmanouil; Kumar Tula, Anjan; Gani, Rafiqul

    2016-01-01

    A method for the selection of appropriate solvents for the solvent swap task in pharmaceutical processes has been developed. This solvent swap method is based on the solvent selection method of Gani et al. (2006) and considers additional selection criteria such as boiling point difference...... in pharmaceutical processes as well as new solvent swap alternatives. The method takes into account process considerations such as batch distillation and crystallization to achieve the swap task. Rigorous model based simulations of the swap operation are performed to evaluate and compare the performance...

  19. Solvent distillation studies for a purex reprocessing plant

    International Nuclear Information System (INIS)

    Ginisty, C.; Guillaume, B.

    1990-01-01

    A distillation system has been developed for regeneration of Purex solvent and will be implemented for the first time in a reprocessing plant. The results are described and analyzed, with emphasis on laboratory experiments which were made with a radioactive plant solvent. Particularly the distillation provides a good separation of solvent degradation products, which was verified by measurements of interfacial tension and plutonium or ruthenium retention. 16 refs., 3 figs., 5 tabs

  20. Improvements in solvent extraction columns

    International Nuclear Information System (INIS)

    Aughwane, K.R.

    1987-01-01

    Solvent extraction columns are used in the reprocessing of irradiated nuclear fuel. For an effective reprocessing operation a solvent extraction column is required which is capable of distributing the feed over most of the column. The patent describes improvements in solvent extractions columns which allows the feed to be distributed over an increased length of column than was previously possible. (U.K.)

  1. Radiation Exposure During Uterine Artery Embolization: Effective Measures to Minimize Dose to the Patient

    Energy Technology Data Exchange (ETDEWEB)

    Scheurig-Muenkler, Christian, E-mail: christian.scheurig@charite.de [Charité Universitaetsmedizin Berlin, Department of Diagnostic and Interventional Radiology (Germany); Powerski, Maciej J., E-mail: maciej.powerski@med.ovgu.de [University of Magdeburg, Department of Radiology and Nuclear Medicine (Germany); Mueller, Johann-Christoph, E-mail: johann-christoph.mueller@charite.de [Charité Universitaetsmedizin Berlin, Department of Diagnostic and Interventional Radiology (Germany); Kroencke, Thomas J., E-mail: Thomas.Kroencke@klinikum-augsburg.de [Klinikum Augsburg, Department of Radiology (Germany)

    2015-06-15

    PurposeEvaluation of patient radiation exposure during uterine artery embolization (UAE) and literature review to identify techniques minimizing required dose.MethodsA total of 224 of all included 286 (78 %) women underwent UAE according to a standard UAE-protocol (bilateral UAE from unilateral approach using a Rösch inferior mesenteric and a microcatheter, no aortography, no ovarian artery catheterization or embolization) and were analyzed for radiation exposure. Treatment was performed on three different generations of angiography systems: (I) new generation flat-panel detector (N = 108/151); (II) classical image amplifier and pulsed fluoroscopy (N = 79/98); (III) classical image amplifier and continuous fluoroscopy (N = 37/37). Fluoroscopy time (FT) and dose-area product (DAP) were documented. Whenever possible, the following dose-saving measures were applied: optimized source-object, source-image, and object-image distances, pulsed fluoroscopy, angiographic runs in posterior-anterior direction with 0.5 frames per second, no magnification, tight collimation, no additional aortography.ResultsIn a standard bilateral UAE, the use of the new generation flat-panel detector in group I led to a significantly lower DAP of 3,156 cGy × cm{sup 2} (544–45,980) compared with 4,000 cGy × cm{sup 2} (1,400–13,000) in group II (P = 0.033). Both doses were significantly lower than those of group III with 8,547 cGy × cm{sup 2} (3,324–35,729; P < 0.001). Other reasons for dose escalation were longer FT due to difficult anatomy or a large leiomyoma load, additional angiographic runs, supplementary ovarian artery embolization, and obesity.ConclusionsThe use of modern angiographic units with flat panel detectors and strict application of methods of radiation reduction lead to a significantly lower radiation exposure. Target DAP for UAE should be kept below 5,000 cGy × cm{sup 2}.

  2. Comparison of Model Calculations of Biological Damage from Exposure to Heavy Ions with Measurements

    Science.gov (United States)

    Kim, Myung-Hee Y.; Hada, Megumi; Cucinotta, Francis A.; Wu, Honglu

    2014-01-01

    The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the major protection to astronauts from harmful exposure. Unlike low-LET gamma or X rays, the presence of shielding does not always reduce the radiation risks for energetic charged-particle exposure. Dose delivered by the charged particle increases sharply at the Bragg peak. However, the Bragg curve does not necessarily represent the biological damage along the particle path since biological effects are influenced by the track structures of both primary and secondary particles. Therefore, the ''biological Bragg curve'' is dependent on the energy and the type of the primary particle and may vary for different biological end points. Measurements of the induction of micronuclei (MN) have made across the Bragg curve in human fibroblasts exposed to energetic silicon and iron ions in vitro at two different energies, 300 MeV/nucleon and 1 GeV/nucleon. Although the data did not reveal an increased yield of MN at the location of the Bragg peak, the increased inhibition of cell progression, which is related to cell death, was found at the Bragg peak location. These results are compared to the calculations of biological damage using a stochastic Monte-Carlo track structure model, Galactic Cosmic Ray Event-based Risk Model (GERM) code (Cucinotta, et al., 2011). The GERM code estimates the basic physical properties along the passage of heavy ions in tissue and shielding materials, by which the experimental set-up can be interpreted. The code can also be used to describe the biophysical events of interest in radiobiology, cancer therapy, and space exploration. The calculation has shown that the severely damaged cells at the Bragg peak are more likely to go through reproductive death, the so called "overkill".

  3. Measuring attitudes about women's recourse after exposure to intimate partner violence: the ATT-RECOURSE scale.

    Science.gov (United States)

    Yount, Kathryn M; VanderEnde, Kristin; Zureick-Brown, Sarah; Minh, Tran Hung; Schuler, Sidney Ruth; Anh, Hoang Tu

    2014-06-01

    Attitudes about intimate partner violence (IPV) against women are widely surveyed, but attitudes about women's recourse after exposure to IPV are understudied, despite their importance for intervention. Designed through qualitative research and administered in a probability sample of 1,054 married men and women 18 to 50 years in My Hao District, Vietnam, the ATT-RECOURSE scale measures men's and women's attitudes about a wife's recourse after exposure to physical IPV. Data were initially collected for nine items. Exploratory factor analysis (EFA) with one random split-half sample (N 1 = 526) revealed a one-factor model with significant loadings (0.316-0.686) for six items capturing a wife's silence, informal recourse, and formal recourse. A confirmatory factor analysis (CFA) with the other random split-half sample (N 2 = 528) showed adequate fit for the six-item model and significant factor loadings of similar magnitude to the EFA results (0.412-0.669). For the six items retained, men consistently favored recourse more often than did women (52.4%-66.0% of men vs. 41.9%-55.2% of women). Tests for uniform differential item functioning (DIF) by gender revealed one item with significant uniform DIF, and adjusting for this revealed an even larger gap in men's and women's attitudes, with men favoring recourse, on average, more than women. The six-item ATT-RECOURSE scale is reliable across independent samples and exhibits little uniform DIF by gender, supporting its use in surveys of men and women. Further methodological research is discussed. Research is needed in Vietnam about why women report less favorable attitudes than men regarding women's recourse after physical IPV.

  4. Exposure levels to radiation in a nuclear medicine laboratory: measurements with thermoluminescence dosemeters

    International Nuclear Information System (INIS)

    Ruiz J, A.

    2000-01-01

    Since 1996 in the Nuclear medicine Department and another routine and research departments of the National Institute of Medical and Nutrition Sciences (INCMNSZ) are working at least with 12 radioactive sources opened and sealed. However, it was unknown if with the Tl personal dosemeters with lithium fluoride crystals (LiF), could be possible to receive information about the equivalent dose for each radionuclide or if there was some radionuclide that by being low energy emissor or beta energy emissor, it did not represent an ionization power sufficient to excite the crystals of the thermoluminescent dosemeters (DTL). In this work the obtained results with control dosemeters of diverse source opened or sealed are shown, which were put at 1 cm of the LiF crystals during a time exposure 18 hours. Therefore the objective of this work is to verify which sources excite or not to DTL crystals and taking the pertinent safety measures for each radionuclide. The conclusion is that the majority of dosemeters were excited by beta or gamma radiation of the radionuclides and that LiF crystals are able to receive equivalent doses until 1200 mSv, being this a guarantee for the staff, that in an any moment could be exposed to high dose in his working day. Also it was corroborated that the radionuclides more energizer are: iodine-131, iodine-125 and sodium-22 while the phosphorus-32 must be managed with careful, since the exposure to hands can result significant, just like the technetium-99m ( 99m Tc). (Author)

  5. Solvent extraction columns

    International Nuclear Information System (INIS)

    Middleton, P.; Smith, J.R.

    1979-01-01

    In pulsed columns for use in solvent extraction processes, e.g. the reprocessing of nuclear fuel, the horizontal perforated plates inside the column are separated by interplate spacers manufactured from metallic neutron absorbing material. The spacer may be in the form of a spiral or concentric circles separated by radial limbs, or may be of egg-box construction. Suitable neutron absorbing materials include stainless steel containing boron or gadolinium, hafnium metal or alloys of hafnium. (UK)

  6. Soft, stretchable, epidermal sensor with integrated electronics and photochemistry for measuring personal UV exposures.

    Directory of Open Access Journals (Sweden)

    Yunzhou Shi

    Full Text Available Excessive ultraviolet (UV radiation induces acute and chronic effects on the skin, eye and immune system. Personalized monitoring of UV radiation is thus paramount to measure the extent of personal sun exposure, which could vary with environment, lifestyle, and sunscreen use. Here, we demonstrate an ultralow modulus, stretchable, skin-mounted UV patch that measures personal UV doses. The patch contains functional layers of ultrathin stretchable electronics and a photosensitive patterned dye that reacts to UV radiation. Color changes in the photosensitive dyes correspond to UV radiation intensity and are analyzed with a smartphone camera. A software application has feature recognition, lighting condition correction, and quantification algorithms that detect and quantify changes in color. These color changes are then correlated with corresponding shifts in UV dose, and compared to existing UV dose risk levels. The soft mechanics of the UV patch allow for multi-day wear in the presence of sunscreen and water. Two evaluation studies serve to demonstrate the utility of the UV patch during daily activities with and without sunscreen application.

  7. Measurement of radiation exposure in attendants of thyroid cancer patients treated with 131I

    International Nuclear Information System (INIS)

    Ramirez G, Y. T.

    2012-01-01

    Patients treated with 131 I for differentiated thyroid cancer present radiological risk to relatives, occupational exposed workers and general public. Recently, the IAEA issued document K-9010241, 2010, which recommends that patient discharge from hospital must be based on the particular status of each patient, unlike the current criteria applied in Mexico based on the exposure rate at a 1 m distance. In this work thermoluminescent dosimeters were used during a 15 day period to measure the effective dose received by 40 family caregivers of patients treated with 131 I, after their release from hospital 'Instituto Nacional de Cancerologia', Mexico. Relatives were classified in two groups, ambulatory (outpatients) and hospitalized (inpatients), according to the release mode of the patient. Measurements were performed for 20 family caregivers in each group. The effective dose received by all family members of outpatient and inpatient groups was found to be smaller that 5 mSv. In addition, 70 and 90% of inpatient and outpatient groups, respectively, received doses lower than 1 mSv. These data provide information which allow to give recommendations of possible modifications to current regulations in Mexico regarding discharge from hospital of patients treated with radiopharmaceuticals. (Author)

  8. Soft, stretchable, epidermal sensor with integrated electronics and photochemistry for measuring personal UV exposures.

    Science.gov (United States)

    Shi, Yunzhou; Manco, Megan; Moyal, Dominique; Huppert, Gil; Araki, Hitoshi; Banks, Anthony; Joshi, Hemant; McKenzie, Richard; Seewald, Alex; Griffin, Guy; Sen-Gupta, Ellora; Wright, Donald; Bastien, Philippe; Valceschini, Florent; Seité, Sophie; Wright, John A; Ghaffari, Roozbeh; Rogers, John; Balooch, Guive; Pielak, Rafal M

    2018-01-01

    Excessive ultraviolet (UV) radiation induces acute and chronic effects on the skin, eye and immune system. Personalized monitoring of UV radiation is thus paramount to measure the extent of personal sun exposure, which could vary with environment, lifestyle, and sunscreen use. Here, we demonstrate an ultralow modulus, stretchable, skin-mounted UV patch that measures personal UV doses. The patch contains functional layers of ultrathin stretchable electronics and a photosensitive patterned dye that reacts to UV radiation. Color changes in the photosensitive dyes correspond to UV radiation intensity and are analyzed with a smartphone camera. A software application has feature recognition, lighting condition correction, and quantification algorithms that detect and quantify changes in color. These color changes are then correlated with corresponding shifts in UV dose, and compared to existing UV dose risk levels. The soft mechanics of the UV patch allow for multi-day wear in the presence of sunscreen and water. Two evaluation studies serve to demonstrate the utility of the UV patch during daily activities with and without sunscreen application.

  9. Soft, stretchable, epidermal sensor with integrated electronics and photochemistry for measuring personal UV exposures

    Science.gov (United States)

    Shi, Yunzhou; Manco, Megan; Moyal, Dominique; Huppert, Gil; Araki, Hitoshi; Banks, Anthony; Joshi, Hemant; McKenzie, Richard; Seewald, Alex; Griffin, Guy; Sen-Gupta, Ellora; Wright, Donald; Bastien, Philippe; Valceschini, Florent; Seité, Sophie; Wright, John A.; Ghaffari, Roozbeh; Rogers, John; Balooch, Guive

    2018-01-01

    Excessive ultraviolet (UV) radiation induces acute and chronic effects on the skin, eye and immune system. Personalized monitoring of UV radiation is thus paramount to measure the extent of personal sun exposure, which could vary with environment, lifestyle, and sunscreen use. Here, we demonstrate an ultralow modulus, stretchable, skin-mounted UV patch that measures personal UV doses. The patch contains functional layers of ultrathin stretchable electronics and a photosensitive patterned dye that reacts to UV radiation. Color changes in the photosensitive dyes correspond to UV radiation intensity and are analyzed with a smartphone camera. A software application has feature recognition, lighting condition correction, and quantification algorithms that detect and quantify changes in color. These color changes are then correlated with corresponding shifts in UV dose, and compared to existing UV dose risk levels. The soft mechanics of the UV patch allow for multi-day wear in the presence of sunscreen and water. Two evaluation studies serve to demonstrate the utility of the UV patch during daily activities with and without sunscreen application. PMID:29293664

  10. Hazardous solvent substitution

    International Nuclear Information System (INIS)

    Twitchell, K.E.

    1995-01-01

    Eliminating hazardous solvents is good for the environment, worker safety, and the bottom line. However, even though we are motivated to find replacements, the big question is 'What can we use as replacements for hazardous solvents?'You, too, can find replacements for your hazardous solvents. All you have to do is search for them. Search through the vendor literature of hundreds of companies with thousands of products. Ponder the associated material safety data sheets, assuming of course that you can obtain them and, having obtained them, that you can read them. You will want to search the trade magazines and other sources for product reviews. You will want to talk to users about how well the product actually works. You may also want to check US Environmental Protection Agency (EPA) and other government reports for toxicity and other safety information. And, of course, you will want to compare the product's constituent chemicals with the many hazardous constituency lists to ensure the safe and legal use of the product in your workplace

  11. Risk assessments for exposure of deployed military personnel to insecticides and personal protective measures used for disease-vector management.

    Science.gov (United States)

    Macedo, Paula A; Peterson, Robert K D; Davis, Ryan S

    2007-10-01

    Infectious diseases are problematic for deployed military forces throughout the world, and, historically, more military service days have been lost to insect-vectored diseases than to combat. Because of the limitations in efficacy and availability of both vaccines and therapeutic drugs, vector management often is the best tool that military personnel have against most vector-borne pathogens. However, the use of insecticides may raise concerns about the safety of their effects on the health of the military personnel exposed to them. Therefore, our objective was to use risk assessment methodologies to evaluate health risks to deployed U.S. military personnel from vector management tactics. Our conservative tier-1, quantitative risk assessment focused on acute, subchronic, and chronic exposures and cancer risks to military personnel after insecticide application and use of personal protective measures in different scenarios. Exposures were estimated for every scenario, chemical, and pathway. Acute, subchronic, and chronic risks were assessed using a margin of exposure (MOE) approach. Our MOE was the ratio of a no-observed-adverse-effect level (NOAEL) to an estimated exposure. MOEs were greater than the levels of concern (LOCs) for all surface residual and indoor space spraying exposures, except acute dermal exposure to lambda-cyhalothrin. MOEs were greater than the LOCs for all chemicals in the truck-mounted ultra-low-volume (ULV) exposure scenario. The aggregate cancer risk for permethrin exceeded 1 x 10(-6), but more realistic exposure refinements would reduce the cancer risk below that value. Overall, results indicate that health risks from exposures to insecticides and personal protective measures used by military personnel are low.

  12. Media Exposure in Low-Income Preschool-Aged Children Is Associated with Multiple Measures of Self-Regulatory Behavior.

    Science.gov (United States)

    Munzer, Tiffany G; Miller, Alison L; Peterson, Karen E; Brophy-Herb, Holly E; Horodynski, Mildred A; Contreras, Dawn; Sturza, Julie; Lumeng, Julie C; Radesky, Jenny

    2018-05-01

    Excessive screen media exposure in childhood is associated with parent-reported self-regulation difficulties. No studies have used laboratory-based or teacher-reported measures of child self-regulatory behaviors. This study examines cross-sectional associations between preschooler screen media exposure and multiple measures of self-regulatory behaviors. Preintervention data were used from 541 preschoolers in the Growing Healthy study, an obesity prevention trial (2011-2015). Screen media exposure was measured by daily screen media exposure (hr/d), television (TV) in the bedroom, frequency of background TV, and TV with meals (1 = rarely/never, 4 = frequently). Child self-regulatory behaviors were measured by the following: child ability to delay gratification, a standardized waiting paradigm; teacher-reported Social Competence and Behavior Evaluation; and parent-reported difficult temperament on the Child Behavior Questionnaire (CBQ). Multivariate regression analyses modeled screen media exposure predicting each self-regulatory measure, adjusting for child age, sex, parent age, education, marital status, income-to-needs ratio, number of adults in household, parent depressive symptoms, and sensitivity. Children were aged 4.1 years (SD = 0.5), parents were aged 29.6 years (SD = 6.8), 48% had high school education or less, and 67% were married. Daily screen media exposure and background TV were associated with weaker observed self-regulation (β: -10.30 seconds for each hr/d media, -12.63 seconds for 1-point increase, respectively). Background TV and TV with meals were associated with greater parent-reported difficult temperament (β: 0.04 and 0.05 CBQ, respectively, for 1-point increase). Greater screen media exposure had small but significant associations with weaker observed and parent-reported, but not teacher-reported, self-regulatory behaviors. Longitudinal studies are needed to determine the directionality of associations.

  13. Measuring combined exposure to environmental pressures in urban areas: an air quality and noise pollution assessment approach.

    Science.gov (United States)

    Vlachokostas, Ch; Achillas, Ch; Michailidou, A V; Moussiopoulos, Nu

    2012-02-01

    This study presents a methodological scheme developed to provide a combined air and noise pollution exposure assessment based on measurements from personal portable monitors. Provided that air and noise pollution are considered in a co-exposure approach, they represent a significant environmental hazard to public health. The methodology is demonstrated for the city of Thessaloniki, Greece. The results of an extensive field campaign are presented and the variations in personal exposure between modes of transport, routes, streets and transport microenvironments are evaluated. Air pollution and noise measurements were performed simultaneously along several commuting routes, during the morning and evening rush hours. Combined exposure to environmental pollutants is highlighted based on the Combined Exposure Factor (CEF) and Combined Dose and Exposure Factor (CDEF). The CDEF takes into account the potential relative uptake of each pollutant by considering the physical activities of each citizen. Rather than viewing environmental pollutants separately for planning and environmental sustainability considerations, the possibility of an easy-to-comprehend co-exposure approach based on these two indices is demonstrated. Furthermore, they provide for the first time a combined exposure assessment to these environmental pollutants for Thessaloniki and in this sense they could be of importance for local public authorities and decision makers. A considerable environmental burden for the citizens of Thessaloniki, especially for VOCs and noise pollution levels is observed. The material herein points out the importance of measuring public health stressors and the necessity of considering urban environmental pollution in a holistic way. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. 19F NMR spectroscopy in monitoring fluorinated-solvent regeneration

    International Nuclear Information System (INIS)

    Ogorodnikov, V.D.; Bordunov, V.V.

    1987-01-01

    Extensive use is made of solvents such as trichloroethylene, freon-133, and perchloroethylene because they are good solvents for inorganic, plant, and animal greases, while the solvents can be recovered and there is no fire hazard. In this paper, the authors examined methods to monitor spent solution regeneration rapidly and with high accuracy. The authors tested perfluorinated telomeric alcohols as solvents for cleaning engineering components which have melting points of 60-120 degrees celsius. The higher working temperatures and the increased energy consumption are disadvantages of these solvents, but these are compensated for by the scope for using them virtually in the solid, liquid, and vapor states. The authors' proposed technology is based on solvents with melting points over 40 degrees celsius which produce virtually no wastes. The telomeric alcohols are recovered after cooling to normal conditions by separation from the oil by filtration and centrifugation, and they can be used in the next purification cycle. When the solvents have been regenerated, the petroleum products such as industrial oils can be reused for their original purpose. However, quantitative data are required on the solvent contents in the oil and the oil contents in the solvent in order to determine the degree of regeneration and the modes to be used. The authors have also proposed a quantitative method of determining traces of these alcohols in oils and residual oils in the solvent by fluorine NMR. All measurements were made with a BS497 NMR spectrometer

  15. Neurobehavioral evaluation of Venezuelan workers exposed to organic solvent mixtures.

    Science.gov (United States)

    Escalona, E; Yanes, L; Feo, O; Maizlish, N

    1995-01-01

    To assess the applicability of the World Health Organization (WHO) Neurobehavioral Core Test Battery (NCTB), we evaluated 53 male and 29 female Venezuelan workers exposed to mixtures of organic solvents in an adhesive factory, and 56 male and 11 female workers unexposed to any type of neurotoxic chemical. The average age of unexposed workers was 30 years and 33 years for those exposed, average schooling for both groups was 8 years, and the mean duration of exposure was 7 years. The NCTB, which assesses central nervous system functions, is composed of seven tests that measure simple motor function, short-term memory, eye-hand coordination, affective behavior, and psychomotor perception and speed. The battery includes: profile of mood states (POMS); Simple Reaction Time for attention and response speed; Digit Span for auditory memory; Santa Ana manual dexterity; Digit-Symbol for perceptual motor speed; the Benton visual retention for visual perception and memory; and Pursuit Aiming II for motor steadiness. In each of 13 subtests, the exposed group had a poorer performance than the nonexposed group. The range of differences in mean performance was between 5% and 89%, particularly in POMS (tension-anxiety, anger-hostility, depression-rejection, fatigue-inertia, confusion-bewilderment), Simple Reaction Time, Digit-Symbol, and Santa Ana Pegboard (p memory, confusion, paresthesias in upper and lower extremities, and sleep disturbances. We conclude that the methodology is applicable to the population studied. The tests of the NCTB were accepted by the subjects and were administered satisfactorily, except for occasional difficulties in verbal comprehension in subtests of POMS, which is the only test that requires more demanding verbal skills. The magnitude of the behavioral deficits is consistent with the probable high level of exposure and with the range of deficits previously reported in workers with long-term solvent exposures.

  16. Solvent mimicry with methylene carbene to probe protein topography.

    Science.gov (United States)

    Gómez, Gabriela Elena; Monti, José Luis E; Mundo, Mariana Rocío; Delfino, José María

    2015-10-06

    The solvent accessible surface area (SASA) of the polypeptide chain plays a key role in protein folding, conformational change, and interaction. This fundamental biophysical parameter is elusive in experimental measurement. Our approach to this problem relies on the reaction of the minimal photochemical reagent diazirine (DZN) with polypeptides. This reagent (i) exerts solvent mimicry because its size is comparable to water and (ii) shows scant chemical selectivity because it generates extremely reactive methylene carbene. Methylation gives rise to the EM (extent of modification) signal, which is useful for scrutinizing the conformational change triggered by Ca(2+) binding to calmodulin (CaM). The increased EM observed for the full protein is dominated by the enhanced exposure of hydrophobic area in Ca(2+)-CaM. Fragmentation allowed us to quantify the methylene incorporation at specific sites. Peptide 91-106 reveals a major reorganization around the calcium 151 binding site, resulting in local ordering and a greater exposure of the hydrophobic surface. Additionally, this technique shows a high sensitivity to probe recognition between CaM and melittin (Mel). The large decrease in EM indicates the occlusion of a significant hydrophobic area upon complexation. Protection from labeling reveals a larger involvement of the N-terminal and central regions of CaM in this interaction. Despite its smaller size, Mel's differential exposure can also be quantified. Moreover, MS/MS fragmentation realizes the goal of extending the resolution of labeled sites at the amino acid level. Overall, DZN labeling emerges as a useful footprinting method capable of shedding light on physiological conformational changes and interactions.

  17. Measures to reduce occupational radiation exposure in PET facilities from nurses' point of view

    International Nuclear Information System (INIS)

    Miyazawa, Keiko; Takahashi, Juri; Mochiduki, Yoshikazu

    2006-01-01

    In parallel with the increase in the number of institutions having PET facilities, the number of nurse working in these facilities has also increased, and the issue of occupational radiation exposure has assumed ever greater importance. In our clinic, since nurses have started to administer FDG intravenous injections, their annual radiation exposure has amounted to 4.8 - 7.1 mSv. To reduce their annual radiation exposure to less than 5 mSv, we identified sources of increased exposure and considered countermeasures based on this information. By implementing countermeasures such as improvements in daily working conditions and ways to avoid various troubles, it was possible to reduce the annual radiation exposure of all nurses to less than 5 mSv. Our experience demonstrates that to provide a working environment with a minimum of occupational radiation exposure, educational training and enhancement of knowledge and technical skills are vital. (author)

  18. SOLVENT FIRE BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Walker, D; Samuel Fink, S

    2006-05-22

    Southwest Research Institute (SwRI) conducted a burn test of the Caustic-Side Solvent Extraction (CSSX) solvent to determine the combustion products. The testing showed hydrogen fluoride gas is not a combustion product from a solvent fire when up to 70% of the solvent is consumed. The absence of HF in the combustion gases may reflect concentration of the modifier containing the fluoride groups in the unburned portion. SwRI reported results for other gases (CO, HCN, NOx, formaldehyde, and hydrocarbons). The results, with other supporting information, can be used for evaluating the consequences of a facility fire involving the CSSX solvent inventory.

  19. How Questionnaires and Multimedia Measurements collected in the U.S. EPA’s Observational Human Exposure Measurement Studies Inform Exposures

    Science.gov (United States)

    In the last decade, the U.S. EPA has conducted and/or funded numerous observational humanexposure measurement studies where questionnaires were administered to the study participants in addition tothe collection of multimedia measurements. Questionnaire responses provide ancillar...

  20. MR signal-fat-fraction analysis and T2* weighted imaging measure BAT reliably on humans without cold exposure.

    Science.gov (United States)

    Holstila, Milja; Pesola, Marko; Saari, Teemu; Koskensalo, Kalle; Raiko, Juho; Borra, Ronald J H; Nuutila, Pirjo; Parkkola, Riitta; Virtanen, Kirsi A

    2017-05-01

    Brown adipose tissue (BAT) is compositionally distinct from white adipose tissue (WAT) in terms of triglyceride and water content. In adult humans, the most significant BAT depot is localized in the supraclavicular area. Our aim is to differentiate brown adipose tissue from white adipose tissue using fat T2* relaxation time mapping and signal-fat-fraction (SFF) analysis based on a commercially available modified 2-point-Dixon (mDixon) water-fat separation method. We hypothesize that magnetic resonance (MR) imaging can reliably measure BAT regardless of the cold-induced metabolic activation, with BAT having a significantly higher water and iron content compared to WAT. The supraclavicular area of 13 volunteers was studied on 3T PET-MRI scanner using T2* relaxation time and SFF mapping both during cold exposure and at ambient temperature; and 18 F-FDG PET during cold exposure. Volumes of interest (VOIs) were defined semiautomatically in the supraclavicular fat depot, subcutaneous WAT and muscle. The supraclavicular fat depot (assumed to contain BAT) had a significantly lower SFF and fat T2* relaxation time compared to subcutaneous WAT. Cold exposure did not significantly affect MR-based measurements. SFF and T2* values measured during cold exposure and at ambient temperature correlated inversely with the glucose uptake measured by 18 F-FDG PET. Human BAT can be reliably and safely assessed using MRI without cold activation and PET-related radiation exposure. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. A Pilot Study Comparing Observational and Questionnaire Surrogate Measures of Pesticide Exposure Among Residents Impacted by the Ecuadorian Flower Industry.

    Science.gov (United States)

    Handal, Alexis J; McGough-Maduena, Alison; Páez, Maritza; Skipper, Betty; Rowland, Andrew S; Fenske, Richard A; Harlow, Siobán D

    2015-01-01

    Self-reported measures of residential pesticide exposure are commonly used in epidemiological studies, especially when financial and logistical resources are limited. However, self-reporting is prone to misclassification bias. This pilot study assesses the agreement between self-report of residential pesticide exposure with direct observation measures, in an agricultural region of Ecuador, as a cross-validation method in 26 participants (16 rose workers and 10 controls), with percent agreement and kappa statistics calculated. Proximity of homes to nearby flower farms was found to have only fair agreement (kappa =.35). The use of discarded plastics (kappa =.06) and wood (kappa =.13) were found to have little agreement. Results indicate that direct observation or measurement may provide more accurate appraisals of residential exposures, such as proximity to industrial farmland and the use of discarded materials obtained from the flower farms.

  2. Dermal Exposure Associated with Occupational End Use of Pesticides and the Role of Protective Measures

    Directory of Open Access Journals (Sweden)

    Ewan MacFarlane

    2013-09-01

    Conclusions: Although international and national efforts to reduce pesticide exposure through regulatory means should continue, it is difficult in the agricultural sector to implement engineering or system controls. It is clear that use of PPE does reduce dermal pesticide exposure but compliance among the majority of occupationally exposed pesticide end users appears to be poor. More research is needed on higher-order controls to reduce pesticide exposure and to understand the reasons for poor compliance with PPE and identify effective training methods.

  3. Effect of Organic Solvents on Microalgae Growth, Metabolism and Industrial Bioproduct Extraction: A Review.

    Science.gov (United States)

    Miazek, Krystian; Kratky, Lukas; Sulc, Radek; Jirout, Tomas; Aguedo, Mario; Richel, Aurore; Goffin, Dorothee

    2017-07-04

    In this review, the effect of organic solvents on microalgae cultures from molecular to industrial scale is presented. Traditional organic solvents and solvents of new generation-ionic liquids (ILs), are considered. Alterations in microalgal cell metabolism and synthesis of target products (pigments, proteins, lipids), as a result of exposure to organic solvents, are summarized. Applications of organic solvents as a carbon source for microalgal growth and production of target molecules are discussed. Possible implementation of various industrial effluents containing organic solvents into microalgal cultivation media, is evaluated. The effect of organic solvents on extraction of target compounds from microalgae is also considered. Techniques for lipid and carotenoid extraction from viable microalgal biomass (milking methods) and dead microalgal biomass (classical methods) are depicted. Moreover, the economic survey of lipid and carotenoid extraction from microalgae biomass, by means of different techniques and solvents, is conducted.

  4. Measuring lifetime stress exposure and protective factors in life course research on racial inequality and birth outcomes.

    Science.gov (United States)

    Malat, Jennifer; Jacquez, Farrah; Slavich, George M

    2017-07-01

    There has been a long-standing interest in better understanding how social factors contribute to racial disparities in health, including birth outcomes. A recent emphasis in this context has been on identifying the effects of stress exposure and protective factors experienced over the entire lifetime. Yet despite repeated calls for a life course approach to research on this topic, very few studies have actually assessed how stressors and protective factors occurring over women's lives relate to birth outcomes. We discuss this issue here by describing how challenges in the measurement of lifetime stress exposure and protective factors have prevented researchers from developing an empirically-based life course perspective on health. First, we summarize prevailing views on racial inequality and birth outcomes; second, we discuss measurement challenges that exist in this context; and finally, we describe both new tools and needed tools for assessing lifetime stress exposure and suggest opportunities for integrating information on stress exposure and psychosocial protective factors. We conclude that more studies are needed that integrate information about lifetime stress exposures and the protective factors that promote resilience against such exposures to inform policy and practice recommendations to reduce racial disparities in birth outcomes.

  5. Lung toxicity determination by in vitro exposure at the air liquid interface with an integrated online dose measurement

    International Nuclear Information System (INIS)

    Muelhopt, Sonja; Paur, H-R; Diabate, S; Weiss, C; Krebs, T

    2009-01-01

    Epidemiological studies show an association between the concentration of ultrafine particles in the atmosphere and the rate of mortality or morbidity due to respiratory and cardiovascular diseases. For the quantitative assessment of the toxicity of airborne nanoparticles the dose-response relationship is tested in in vitro test systems using bioassays of cell cultures as sensor. For the air-liquid interface exposure of cell cultures towards aerosols the Karlsruhe exposure system was developed. The human lung cell cultures are exposed in VITROCELL (registered) system modules with a constant flow of the conditioned aerosol. After exposure the cells are analyzed to measure the biological responses such as viability, inflammatory or oxidative stress. For the determination of the dose response relationship the accurate knowledge of the deposited particle mass is essential. A new online method is developed in the Karlsruhe exposure system: the sensor of a quartz crystal microbalance is placed in an exposure chamber instead of the membrane insert and exposed to the aerosol in the same way as the cell cultures. The deposited mass per area unit is monitored as a function of exposure time showing a linear relationship for a constant aerosol flow with defined particle concentration. A comparison of this new dose signal to a dosimetry method using fluorescein sodium particles shows a very good correlation between the sensor signal of the quartz crystal microbalance and the deposited mass on the membranes shown by spectroscopy. This system for the first time provides an online dose measurement for in vitro experiments with nanoparticles.

  6. Theoretical and experimental study of mixed solvent electrolytes

    International Nuclear Information System (INIS)

    Cummings, P.T.; O'Connell, J.P.

    1990-01-01

    In the original proposal to study mixed solvent electrolyte solutions, four major goals were formulated: fundamental modeling of mixed solvent electrolytes using numerically solved integral equation approximation theories; evaluation of intermolecular pair potential models by computer simulation of selected systems for comparison with experiment and the numerical integral equation studies; development of fundamentally based correlations for the thermodynamic properties of mixed solvent electrolyte solutions using analytically solvable statistical mechanical models; and extension of experimental database on mixed solvent electrolytes by performing vapor-liquid equilibrium measurements on selected systems. This paper discusses the progress on these goals

  7. A panel study of airborne particulate matter concentration and impaired cardiopulmonary function in young adults by two different exposure measurement

    Science.gov (United States)

    Hu, Li-Wen; Qian, Zhengmin (Min); Bloom, Michael S.; Nelson, Erik J.; Liu, Echu; Han, Bin; Zhang, Nan; Liu, Yimin; Ma, Huimin; Chen, Duo-Hong; Yang, Bo-Yi; Zeng, Xiao-Wen; Chen, Wen; Komppula, Mika; Leskinen, Ari; Hirvonen, Maija-Riitta; Roponen, Marjut; Jalava, Pasi; Bai, Zhipeng; Dong, Guang-Hui

    2018-05-01

    This study sought to clarify the correlation of individual exposure measurements and PM2.5 measurements collected at regulatory monitoring sites in short-term panel study settings. To achieve this goal, 30 young, healthy adult participants were assigned to three groups with 4 samplers in each group to collect individual exposures during four weekends in March 2016. Participants also completed cardiopulmonary function tests during the same periods. For comparison, ambient air pollution data were obtained from the Air Pollution Surveillance Network in Guangzhou, China. The 8-h ambient pollutant averages and group sampler concentrations were used as separate indicators of air pollution exposure. Results showed that the 8-h mean concentration of personal PM2.5 exposure was 65.09 ± 22.18 μg/m3, which was 24.34 μg/m3 statistically higher than the ambient concentrations over the same period (p < 0.05). However, these concentrations were strongly correlated (Spearman's r = 0.937, p < 0.01). Separate mixed-effect models were fit for ambient and personal exposures to estimate their associations with cardiopulmonary outcomes. Higher PM2.5 and PM10 exposures were related to lower lung function of maximal mid-expiratory flow (MMEF). A 10 μg/m3 higher PM was associated with 0.11 L/S to 0.52 L/S lower MMEF. No effects on cardiovascular function were found. In conclusion, personal PM2.5 exposure might be higher than ambient concentrations. Young, healthy adults in urban areas may experience reduced lung function (lower MMEF), even after just 8 h of exposure to PM2.5 and PM10.

  8. Electrothermal piezoresistive cantilever resonators for personal measurements of nanoparticles in workplace exposure

    Science.gov (United States)

    Wasisto, Hutomo Suryo; Wu, Wenze; Uhde, Erik; Waag, Andreas; Peiner, Erwin

    2015-05-01

    Low-cost and low-power piezoresistive cantilever resonators with integrated electrothermal heaters are developed to support the sensing module enhancement of the second generation of handheld cantilever-based airborne nanoparticle (NP) detector (CANTOR-2). These sensors are used for direct-reading of exposure to carbon engineered nanoparticles (ENPs) at indoor workplaces. The cantilever structures having various shapes of free ends are created using silicon bulk micromachining technologies (i.e, rectangular, hammer-head, triangular, and U-shaped cantilevers). For a complete wearable CANTOR-2, all components of the proposed detector can be grouped into two main units depending on their packaging placements (i.e., the NP sampler head and the electronics mounted in a handy-format housing). In the NP sampler head, a miniaturized electrophoretic aerosol sampler and a resonant silicon cantilever mass sensor are employed to collect the ENPs from the air stream to the cantilever surfaces and measuring their mass concentration, respectively. After calibration, the detected ENP mass concentrations of CANTOR-2 show a standard deviation from fast mobility particle sizer (FMPS, TSI 3091) of 8-14%.

  9. Differences in Lipid Measurements by Antiretroviral Regimen Exposure in Cohorts from Asia and Australia

    Directory of Open Access Journals (Sweden)

    Amit C. Achhra

    2012-01-01

    Full Text Available We explored the mean differences in routinely measured lipids (total cholesterol, triglycerides, and high-density lipoprotein cholesterol according to exposure to different combination antiretroviral regimens in Asian (n=2051 and Australian (predominantly Caucasian, n=794 cohorts. The regimen was defined as at least 3 antiretroviral drugs with at least 2 nucleoside-reverse transcriptases (NRTIs and either of at least one protease inhibitor (PI or non-nucleoside-reverse transcriptases (NNRTIs. We categorised cART regimens as: NRTIs as tenofovir based or not; NNRTIs as nevirapine or efavirenz (but not both; and PI as atazanavir based or not. We found that the impact of various antiretroviral regimens on lipids in Asian and Australian cohorts was only different by cohort for total cholesterol (P for interaction between regimen and cohort: 0.05. The differences in total cholesterol were however small and unlikely to be of clinical significance. Overall, tenofovir with nevirapine or atazanavir was associated with the most favorable lipids, while the PI regimens without tenofovir and atazanavir were associated with least favorable lipids. We conclude that the impact of various ART regimens on lipids is largely similar in Asian and Australian cohorts and that the newer drugs such as tenofovir and atazanavir are likely to provide similar benefit in terms of lipid profiles in both populations.

  10. A Comparison of Exposure Control Procedures in CAT Systems Based on Different Measurement Models for Testlets

    Science.gov (United States)

    Boyd, Aimee M.; Dodd, Barbara; Fitzpatrick, Steven

    2013-01-01

    This study compared several exposure control procedures for CAT systems based on the three-parameter logistic testlet response theory model (Wang, Bradlow, & Wainer, 2002) and Masters' (1982) partial credit model when applied to a pool consisting entirely of testlets. The exposure control procedures studied were the modified within 0.10 logits…

  11. Freezing Point Depressions of Phase Change CO2 Solvents

    DEFF Research Database (Denmark)

    Arshad, Muhammad Waseem; Fosbøl, Philip Loldrup; von Solms, Nicolas

    2013-01-01

    Freezing point depressions (FPD) in phase change solvents containing 2-(diethylamino)ethanol (DEEA) and 3-(methylamino)propylamine (MAPA) were measured using a modified Beckmann apparatus. The measurements were performed for the binary aqueous DEEA and MAPA solutions, respectively...

  12. Children's residential exposure to chlorpyrifos: Application of CPPAES field measurements of chlorpyrifos and TCPy within MENTOR/SHEDS-Pesticides model

    International Nuclear Information System (INIS)

    Hore, Paromita; Zartarian, Valerie; Xue Jianping; Ozkaynak, Haluk; Wang, S.-W.; Yang, Y.-C.; Chu, P.-Ling; Sheldon, Linda; Robson, Mark; Needham, Larry; Barr, Dana; Freeman, Natalie; Georgopoulos, Panos; Lioy, Paul J.

    2006-01-01

    The comprehensive individual field-measurements on non-dietary exposure collected in the Children's-Post-Pesticide-Application-Exposure-Study (CPPAES) were used within MENTOR/SHEDS-Pesticides, a physically based stochastic human exposure and dose model. In this application, however, the model was run deterministically. The MENTOR/SHEDS-Pesticides employed the CPPAES as input variables to simulate the exposure and the dose profiles for seven children over a 2-week post-application period following a routine residential and professional indoor crack-and-crevice chlorpyrifos application. The input variables were obtained from a personal activity diary, microenvironmental measurements and personal biomonitoring data obtained from CPPAES samples collected from the individual children and in their homes. Simulation results were compared with CPPAES field measured values obtained from the children's homes to assess the utility of the different microenvironmental data collected in CPPAES, i.e. indicator toys and wipe samplers to estimate aggregate exposures that can be result from one or more exposure pathways and routes. The final analyses of the database involved comparisons of the actual data obtained from the individual biomarker samples of a urinary metabolite of chlorpyrifos (TCPy) and the values predicted by MENTOR/SHEDS-Pesticides using the CPPAES-derived variables. Because duplicate diet samples were not part of the CPPAES study design, SHEDs-Pesticides simulated dose profiles did not account for the dietary route. The research provided more confidence in the types of data that can be used in the inhalation and dermal contact modules of MENTOR/SHEDS-Pesticides to predict the pesticide dose received by a child. It was determined that we still need additional understanding about: (1) the types of activities and durations of activities that result in non-dietary ingestion of pesticides and (2) the influence of dietary exposures on the levels of TCPy found in the

  13. Solvent effects in chemistry

    CERN Document Server

    Buncel, Erwin

    2015-01-01

    This book introduces the concepts, theory and experimental knowledge concerning solvent effects on the rate and equilibrium of chemical reactions of all kinds.  It begins with basic thermodynamics and kinetics, building on this foundation to demonstrate how a more detailed understanding of these effects may be used to aid in determination of reaction mechanisms, and to aid in planning syntheses. Consideration is given to theoretical calculations (quantum chemistry, molecular dynamics, etc.), to statistical methods (chemometrics), and to modern day concerns such as ""green"" chemistry, where ut

  14. Developing a method for the retrospective estimation of radon exposure from in vivo measurements of 210Pb activity in bone

    International Nuclear Information System (INIS)

    McKenzie, R.J.; Johnston, P.N.

    1999-01-01

    Radon is a naturally occurring radioactive gas which has been linked to lung cancer in occupationally exposed uranium mine workers. Where monitoring of an individual's exposure to radon and radon progeny has not occurred or is incomplete, it may be possible to determine this exposure retrospectively by the measurement of the long lived decay product 210 Pb which accumulates in the bones of exposed individuals. This paper describes a method being developed at the whole body monitor (WBM) facility of the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) to estimate the time integrated exposure to radon over a period of up to several decades from the in vivo measurements of 210 Pb activity in the knee of human subjects. Initial work has concentrated on characterising the WBM facility for this work using artificial bone phantoms. This project will serve as a test of the feasibility of the method before undertaking further studies on human subjects

  15. Measurement and simulation of the in-flight radiation exposure on different air routes

    International Nuclear Information System (INIS)

    Hajek, M.; Berger, T.; Vana, N.

    2003-01-01

    The exposure of air-crew personnel to cosmic radiation is considered to be occupational exposure and requirements for dose assessment are given in the European Council Directive 96/29/EURATOM. The High-Temperature Ratio (HTR) Method for LiF: Mg, Ti TLDs utilizes the well-investigated relative intensity of the combined high-temperature glow peaks 6 and 7 compared with the dominant peak 5 (left-hand side of Figure 1) as an indication of the dose-average LET of a mixed radiation field of unknown composition. The difference in the peak-5 readings of the neutron-sensitive TLD-600 ( 6 LiF: Mg, Ti) and the neutron-insensitive TLD-700 ( 7 LiF: Mg, Ti) can be utilized to assess the neutron dose equivalent accumulated in-flight. For this purpose, the dosemeter crystals were calibrated individually in the CERN-EU High Energy Reference Field (CERF) [8] which simulates the cosmic-ray induced neutron spectrum in good detail. The experiments conducted onboard passenger aircraft on different north-bound and trans-equatorial flight routes were aimed at the following: to measure the total dose equivalent accumulated during the flight, to assess the contribution of neutrons, and to compare the results with calculations by means of the well-known CARI computer code. Measurements were performed on a series of eight north-bound flights between Cologne and Washington as well as on the routes Vienna-Atlanta, Vienna-Sydney and Vienna-Tokyo during different solar activity conditions. Precise altitude and route profiles were recorded by the pilots. The experimental results were compared with model calculations using the latest release 6M of the CARI code. Precise altitude and route data on a ten-minute to one-hour scale were taken as input. The calculated dose values indicate that the algorithms employed for the computational assessment of route doses have been significantly improved during the last decade. The CARI results generally tend to be in reasonable agreement with the measured

  16. Solvent effects in the synergistic solvent extraction of Co2+

    International Nuclear Information System (INIS)

    Kandil, A.T.; Ramadan, A.

    1979-01-01

    The extraction of Co 2+ from a 0.1M ionic strength aqueous phase (Na + , CH 3 COOH) of pH = 5.1 was studied using thenoyltrifluoroacetone, HTTA, in eight different solvents and HTTA + trioctylphosphine oxide, TOPO, in the same solvents. A comparison of the effect of solvent dielectric constant on the equilibrium constant shows a synergism as a result of the increased hydrophobic character imparted to the metal complex due to the formation of the TOPO adduct. (author)

  17. Evaluation of occupational exposure in a underground coal mine by environmental measures of 222Rn and in vivo measurements of 210Pb in bones

    International Nuclear Information System (INIS)

    Dantas, A.L.A.; Veiga, L.H.S.; Dantas, B.M.; Melo, V.P.

    2005-01-01

    A radiological survey performed in an underground coal mining in the State of Parana, southern Brazil, has indicated the occurrence of high levels of concentration of radon and its decay products. The levels of 222 Rn concentration measured in the basement of this mine, in the period from 1999 to 2003 ranged from 2000 to 7000 Bq m -3 . It is estimated, for these workers, an average annual exposure of 2.1 WLM ranging from 0.2 to 7.2 WLM. A retrospective mortality study conducted with 2856 miners of this mining indicated a risk of lung cancer mortality greater than the one expected for the male population of the State. In this study the cumulative exposure to radon cannot be estimated since there was no radon measures in other periods. In this way, the cumulative exposure can be evaluated by through 210 Pb activities monitored in the skeleton. The measures of 210 Pb in skeleton ranged from 83 to 164 Bq, indicating that these workers were significantly exposed to 222 Rn. These results show that cumulative exposure to radon has been higher than estimated based on recent measures of the activity concentration of radon in the workplace and is compatible with the risk determined in the epidemiological study

  18. Spatial measurement error and correction by spatial SIMEX in linear regression models when using predicted air pollution exposures.

    Science.gov (United States)

    Alexeeff, Stacey E; Carroll, Raymond J; Coull, Brent

    2016-04-01

    Spatial modeling of air pollution exposures is widespread in air pollution epidemiology research as a way to improve exposure assessment. However, there are key sources of exposure model uncertainty when air pollution is modeled, including estimation error and model misspecification. We examine the use of predicted air pollution levels in linear health effect models under a measurement error framework. For the prediction of air pollution exposures, we consider a universal Kriging framework, which may include land-use regression terms in the mean function and a spatial covariance structure for the residuals. We derive the bias induced by estimation error and by model misspecification in the exposure model, and we find that a misspecified exposure model can induce asymptotic bias in the effect estimate of air pollution on health. We propose a new spatial simulation extrapolation (SIMEX) procedure, and we demonstrate that the procedure has good performance in correcting this asymptotic bias. We illustrate spatial SIMEX in a study of air pollution and birthweight in Massachusetts. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Lessons learnt on biases and uncertainties in personal exposure measurement surveys of radiofrequency electromagnetic fields with exposimeters.

    Science.gov (United States)

    Bolte, John F B

    2016-09-01

    Personal exposure measurements of radio frequency electromagnetic fields are important for epidemiological studies and developing prediction models. Minimizing biases and uncertainties and handling spatial and temporal variability are important aspects of these measurements. This paper reviews the lessons learnt from testing the different types of exposimeters and from personal exposure measurement surveys performed between 2005 and 2015. Applying them will improve the comparability and ranking of exposure levels for different microenvironments, activities or (groups of) people, such that epidemiological studies are better capable of finding potential weak correlations with health effects. Over 20 papers have been published on how to prevent biases and minimize uncertainties due to: mechanical errors; design of hardware and software filters; anisotropy; and influence of the body. A number of biases can be corrected for by determining multiplicative correction factors. In addition a good protocol on how to wear the exposimeter, a sufficiently small sampling interval and sufficiently long measurement duration will minimize biases. Corrections to biases are possible for: non-detects through detection limit, erroneous manufacturer calibration and temporal drift. Corrections not deemed necessary, because no significant biases have been observed, are: linearity in response and resolution. Corrections difficult to perform after measurements are for: modulation/duty cycle sensitivity; out of band response aka cross talk; temperature and humidity sensitivity. Corrections not possible to perform after measurements are for: multiple signals detection in one band; flatness of response within a frequency band; anisotropy to waves of different elevation angle. An analysis of 20 microenvironmental surveys showed that early studies using exposimeters with logarithmic detectors, overestimated exposure to signals with bursts, such as in uplink signals from mobile phones and Wi

  20. Solvent extraction of zirconium

    International Nuclear Information System (INIS)

    Kim, S.S.; Yoon, J.H.

    1981-01-01

    The extraction of zirconium(VI) from an aqueous solution of constant ionic strength with versatic acid-10 dissolved in benzen was studied as a function of pH and the concentration of zirconium(VI) and organic acid. The effects of sulphate and chlorine ions on the extraction of the zirconium(VI) were briefly examined. It was revealed that (ZrOR 2 .2RH) is the predominant species of extracted zirconium(VI) in the versatic acid-10. The chemical equation and the apparent equilibrium constants thereof have been determined as follows. (ZrOsup(2+))aq+ 2(R 2 H 2 )sub(org) = (ZrOR 2 .2RH)sub(org)+2(H + )aq Ksub(Zr) = (ZrOR 2 .2RH)sub(org)(H + ) 2 /(ZrOsup(2+))sub(aq)(R 2 H 2 )sup(2)sub(org) = 3.3 x 10 -7 . The synergistic effects of TBP and D2EHPA were also studied. In the mixed solvent with 0.1M TBP, the synergistic effect was observed, while the mixed solvent with D2EHPA showed the antisynergistic effect. (Author)

  1. 75 FR 58387 - Notice of Issuance of Exposure Draft of a Concepts Statement on Measurement of the Elements of...

    Science.gov (United States)

    2010-09-24

    ... FEDERAL ACCOUNTING STANDARDS ADVISORY BOARD Notice of Issuance of Exposure Draft of a Concepts Statement on Measurement of the Elements of Accrual-Basis Financial Statements in Periods After Initial Recording AGENCY: Federal Accounting Standards Advisory Board. ACTION: Notice. Board Action: Pursuant to 31...

  2. Perspectives on repeated low-level blast and the measurement of neurotrauma in humans as an occupational exposure risk

    Science.gov (United States)

    Carr, W.; Dell, K. C.; Yanagi, M. A.; Hassan, D. M.; LoPresti, M. L.

    2017-11-01

    A pressing question in military medical research is the nature and degree of effects on the human brain from occupational repeated exposure to low-level explosive blast, but reliable and effective means to objectively measure such effects remain elusive. In survey results, headache, difficulty sleeping, irritability, cognitive impairment, and a variety of other symptoms consistent with post-concussive syndrome have been reported by those exposed to blast and there was positive correlation between degree of blast exposure and degree of symptomology, but an important goal is to obtain more objective evidence of an effect than self-report alone. This review reflects recent efforts to measure and evaluate such hypothesized effects and current recommendations for ongoing study. Optimal measures are likely those with sensitivity and specificity to systemic effects in mild neurotrauma, that have minimal to no volitional component, and that can be sampled relatively quickly with minimal intrusion in prospective, observational field studies during routine training with explosives. An understanding of an association between parameters of exposure to repeated low-level blast and negative neurologic effects would support the evaluation of clinical implications and development of protective equipment and surveillance protocols where warranted. At present, low-level blast exposure surveillance measurements do not exist as a systematic record for any professional community.

  3. Measuring tobacco smoke exposure: quantifying nicotine/cotinine concentration in biological samples by colorimetry, chromatography and immunoassay methods.

    Science.gov (United States)

    Dhar, Preeti

    2004-04-01

    Procedures to assess tobacco smoke exposure are reviewed and biomarkers used for determining the smoking status of an individual are compared. Methods used to extract these biomarkers from saliva, urine, and blood and the advantages and disadvantages of the assays are discussed. Finally, the procedures used to measure the levels of cortisol, a stress hormone speculated to be linked to nicotine metabolism, are discussed.

  4. Development and application of a radiometric method of measurement (Heger probe) for characterizing clastic rock strata in exposures

    International Nuclear Information System (INIS)

    Koch, G.

    1984-01-01

    The radiometric image of a stratigraphic exposure profile was to be logged. The method of measurement was tested on clastic sediments of the Tertiary (Saudi Arabia) and Bunter (Northern Germany). The well-tried scintillometer technique was supplemented by modern technological means supplied by a prospecting company (Gewerkschaft Brunhilde). The probe applied was specifically developped for stratigraphic purposes. (orig./HP) [de

  5. Lithographic measurement of EUV flare in the 0.3-NA Micro Exposure Tool optic at the Advanced Light Source

    International Nuclear Information System (INIS)

    Cain, Jason P.; Naulleau, Patrick; Spanos, Costas J.

    2005-01-01

    The level of flare present in a 0.3-NA EUV optic (the MET optic) at the Advanced Light Source at Lawrence Berkeley National Laboratory is measured using a lithographic method. Photoresist behavior at high exposure doses makes analysis difficult. Flare measurement analysis under scanning electron microscopy (SEM) and optical microscopy is compared, and optical microscopy is found to be a more reliable technique. In addition, the measured results are compared with predictions based on surface roughness measurement of the MET optical elements. When the fields in the exposure matrix are spaced far enough apart to avoid influence from surrounding fields and the data is corrected for imperfect mask contrast and aerial image proximity effects, the results match predicted values quite well. The amount of flare present in this optic ranges from 4.7% for 2 (micro)m features to 6.8% for 500 nm features

  6. Use of chromosome translocations for measuring prior environment exposures in humans

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, J. D.

    1997-05-01

    Recent advances in cytogenetic methodology are beginning to have a major impact upon our ability to provide assessments of environmental exposure in humans. The advent of fluorescent-based techniques for `painting` whole chromosomes has made the analysis of chromosome translocations rapid, specific, sensitive and routine. Chromosome painting has been used to address a wide variety of scientific questions, resulting in an increased understanding of the biological consequences of adverse environmental exposure. This paper describes the use of chromosome translocations as a biological marker of exposure and effect in humans. The relevance of translocations is discussed, as are the advantages and disadvantages of painting compared to classical cytogenetic methods for translocation evaluation. The factors to consider in the use of translocations as a retrospective indicator of exposure are then described. Several theoretical parameters that are important to the use of translocations are provided, and the paper concludes with a vision for the future of cytogenetic methodology.

  7. Measuring the Storm: Methods of Quantifying Hurricane Exposure in Public Health

    Science.gov (United States)

    Increasing coastal populations and storm intensity may lead to more adverse health effects from tropical storms and hurricanes. Exposure during pregnancy can influence birth outcomes through mechanisms related to healthcare, infrastructure disruption, stress, nutrition, and inju...

  8. Overview on measures concerning the radiation exposure reduction following events with serious radiological consequences (catalogue of measures) Pt. 2. Background information, theory and examples of use

    International Nuclear Information System (INIS)

    Genkel, Simone; Schnadt, Horst

    2010-01-01

    The report edited by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety includes the following chapters: Summary of materials: international nuclear and radiological event scale (INES), nuclear power plants in Europe, significance of the reference nuclide I-131, emergency protection measures, radiation protection measures, contaminated surface waters, contaminated matter disposal, prevention of radiation exposure by inhalation, decision making concerning agriculture and food, radiation protection during disposal procedures. Theoretical fundamentals: decontamination, dose rate, contaminated soils, inhalation dose, contaminated articles, contaminated surface waters, contaminated skin, contamination by ingestion, conversion factors, calculation procedures for appropriate measures. Examples for use of the catalogue of measures.

  9. Assessment of the Real Life Exposure to 2G and 3G Base Stations Over a Day from Instantaneous Measurement

    OpenAIRE

    Mahfouz , Zaher; Gati , Azeddine; Lautru , David; Wiart , Joe; Hanna , Victor Fouad

    2011-01-01

    International audience; In this paper, the general public daily exposure to mobile telephony is investigated. The considered signals are GSM900, GSM1800, UMTS and HSDPA. The study focus on the assessment of the maximal real electric field received over the day from an instantaneous measurement performed any time during the day. An extrapolation factor is presented to extrapolate an instantaneous measurement for any signal to the maximal possible value received by this signal over the day. Thi...

  10. Prevalence of Hand-transmitted Vibration Exposure among Grass-cutting Workers using Objective and Subjective Measures

    Science.gov (United States)

    Azmir, N. A.; Yahya, M. N.

    2017-01-01

    Extended exposure to hand-transmitted vibration from vibrating machine is associated with an increased occurrence of symptoms of occupational disease related to hand disorder. The present case study is to determine the prevalence and correlation of significant subjective as well as objective variables that induce to hand arm vibration syndrome (HAVS) among hand-held grass-cutting workers in Malaysia. Thus, recommendations are made for grass-cutting workers and grass maintenance service management based on findings. A cross sectional study using adopted subjective Hand Arm Vibration Exposure Risk Assessment (HAVERA) questionnaire from Vibration Injury Network on hand disorder signs and symptoms was distributed to a sample of one hundred and sixty eight male workers from grass and turf maintenance industry that use vibrating machine as part of their work. For objective measure, hand-transmitted vibration measurement was collected on site during operation by the following ISO 5349-1, 2001. Two groups were identified in this research comprising of high exposure group and low-moderate exposure group. Workers also gave information about their personal identification, social history, workers’ health, occupational history and machine safety inspection. There was positive HAVS symptoms relationship between the low-moderate exposure group and high exposure group among hand-held grass-cutting workers. The prevalence ratio (PR) was considered high for experiencing white colour change at fingers and fingers go numb which are 3.63 (1.41 to 9.39) and 4.24 (2.18 to 8.27), respectively. The estimated daily vibration exposure, A(8) differs between 2.1 to 20.7 ms-2 for right hand while 2.7 to 29.1 ms-2 for left hand. The subjects claimed that the feel of numbness at left hand is much stronger compared to right hand. The results suggest that HAVS is diagnosed in Malaysia especially in agriculture sector. The A(8) indicates that the exposure value is more than exposure limit value

  11. Evaluation of the contribution of contamination of radiotherapy room surfaces in the measure of exposure rate of radioiodine therapy patients

    International Nuclear Information System (INIS)

    Campos, Rafael Ferreira

    2015-01-01

    The contamination of radiotherapy room surfaces is significant and the measures of patient exposure rate are held on the fourth dependencies, relevant questions are raised: the background radiation of the room stay high due to surface contamination, may interfere with the rate of patient exposure at the time of its release? The monitoring site is important to determine whether the patient will be released? The value of the deal activity and the clinical condition of the patient may increase the contamination, influencing the monitoring results? This paper aims to conduct a quantitative analysis of surface contamination of the contribution of therapeutic room at the time is monitored exposure rate from inpatient. Measurements were made regarding the hospitalization of 32 patients with different doses administered activity, age and of both genders. The measurements were performed in the therapeutic rooms at the hospital Brotherhood Santa Casa de Misericordia de Sao Paulo. Exposure rate measurements were performed at the center of the room at 1 meter of the patient on the day of its release. After his release and prior to decontamination, measurements were performed at predetermined landmarks within the therapeutic room. The results revealed that on average background radiation, high due to surface contamination contributes only 2% of the patient dose rate. It can be considered that even with influence of contamination of surfaces, this is insignificant to determine if the patient may or may not be released. This study suggests that the site in which monitoring occurs exposure rate of the patient should not be decisive for liberation thereof. (author)

  12. Measurement of radiation exposure in relatives of thyroid cancer patients treated with (131)I.

    Science.gov (United States)

    Ramírez-Garzón, Y T; Ávila, O; Medina, L A; Gamboa-deBuen, I; Rodríguez-Laguna, A; Buenfil, A E; Ruíz-Trejo, C; Estrada, E; Brandan, M E

    2014-11-01

    This work evaluates the radiological risk that patients treated with I for differentiated thyroid cancer could present to relatives and occupationally exposed workers. Recently, the International Atomic Energy Agency issued document K9010241, which recommends that patient discharge from the hospital must be based on the particular status of each patient. This work measures effective dose received by caregivers of patients treated with I at the Instituto Nacional de Cancerología, Mexico City. Thermoluminescent dosimeters were carried during a 15-d period by 40 family caregivers after patient release from hospital. Relatives were classified into two groups, ambulatory and hospitalized, according to the release mode of the patient, and three categories according to the individual patient home and transport facilities. Categories A, B, and C were defined going from most to least adequate concerning public exposure risk. Measurements were performed for 20 family caregivers in each group. The effective dose received by all caregivers participating in this study was found to be less than 5 mSv, the recommended limit per event for caregivers suggested by ICRP 103. In addition, 70 and 90% of ambulatory and hospitalized groups, respectively, received doses lower than 1 mSv. Caregivers belonging to category C, with home situations that are not appropriate for immediate release, received the highest average doses; i.e., 2.2 ± 1.3 and 3.1 ± 1.0 mSv for hospitalized and ambulatory patients, respectively. Results of this work have shown that the proper implementation of radiation protection instructions for relatives and patients can reduce significantly the risk that differentiated thyroid cancer patients treated with I can represent for surrounding individuals. The results also stress the relevance of the patient's particular lifestyle and transport conditions as the prevailing factors related to the dose received by the caregiver. Therefore, the patient's status should be

  13. The measurement of exposure rate and absorbed dose for photons of 6 to 7 MeV

    International Nuclear Information System (INIS)

    Birchall, I.

    1978-01-01

    Using the 16 N source at the Universities Reactor Centre, which provides a source of high energy photons of 6 and 7 MeV, experiments have been carried out to provide a calibration point for secondary standard and general survey instruments. The source was designed primarily for shielding experiments and suffers from a number of disadvantages if precise dose or exposure data are required. In particular the exposure rate is low, the source is physically large and the energy spectrum is contaminated with lower energy photons. A summary of the basic techniques is given because of the inherent difficulties in dose measurements particularly for high energy photons. (author)

  14. Lead exposure in young children over a 5-year period from urban environments using alternative exposure measures with the US EPA IEUBK model - A trial.

    Science.gov (United States)

    Gulson, Brian; Taylor, Alan; Stifelman, Marc

    2018-02-01

    The US Environmental Protection Agency (EPA) Integrated Exposure Uptake Biokinetic (IEUBK) model has been widely used to predict blood lead (PbB) levels in children especially around industrial sites. Exposure variables have strongly focussed on the major contribution of lead (Pb) in soil and interior dust to total intake and, in many studies, site-specific data for air, water, diet and measured PbB were not available. We have applied the IEUBK model to a comprehensive data set, including measured PbB, for 108 children monitored over a 5-year period in Sydney, New South Wales, Australia. To use this data set, we have substituted available data (with or without modification) for standard inputs as needed. For example, as an alternative measure for soil Pb concentration (μg/g), we have substituted exterior dust sweepings Pb concentration (μg/g). As alternative measures for interior dust Pb concentration (μg/g) we have used 1) 30-day cumulative petri dish deposition data (PDD) (as µg Pb/m 2 /30days), or 2) hand wipe data (as μg Pb/hand). For comparison, simulations were also undertaken with estimates of dust Pb concentration derived from a prior regression of dust Pb concentration (μg/g) on dust Pb loading (μg/ft 2 ) as concentration is the unit specified for the Model. Simulations for each subject using observed data aggregated over the 5-year interval of the study, the most usual application of the IEUBK model, showed using Wilcoxon tests that there was a significant difference between the observed values and the values predicted by the Model containing soil with hand wipes (p < 0.001), and soil and PDD (p = 0.026) but not those for the other two sets of predictors, based on sweepings and PDD or sweepings and wipes. Overall, simulations of the Model using alternative exposure measures of petri dish dust (and possibly hand wipes) instead of vacuum cleaner dust and dust sweepings instead of soil provide predicted PbB which are generally consistent with each

  15. Qualitative and quantitative evaluation of solvent systems for countercurrent separation.

    Science.gov (United States)

    Friesen, J Brent; Ahmed, Sana; Pauli, Guido F

    2015-01-16

    Rational solvent system selection for countercurrent chromatography and centrifugal partition chromatography technology (collectively known as countercurrent separation) studies continues to be a scientific challenge as the fundamental questions of comparing polarity range and selectivity within a solvent system family and between putative orthogonal solvent systems remain unanswered. The current emphasis on metabolomic investigations and analysis of complex mixtures necessitates the use of successive orthogonal countercurrent separation (CS) steps as part of complex fractionation protocols. Addressing the broad range of metabolite polarities demands development of new CS solvent systems with appropriate composition, polarity (π), selectivity (σ), and suitability. In this study, a mixture of twenty commercially available natural products, called the GUESSmix, was utilized to evaluate both solvent system polarity and selectively characteristics. Comparisons of GUESSmix analyte partition coefficient (K) values give rise to a measure of solvent system polarity range called the GUESSmix polarity index (GUPI). Solvatochromic dye and electrical permittivity measurements were also evaluated in quantitatively assessing solvent system polarity. The relative selectivity of solvent systems were evaluated with the GUESSmix by calculating the pairwise resolution (αip), the number of analytes found in the sweet spot (Nsw), and the pairwise resolution of those sweet spot analytes (αsw). The combination of these parameters allowed for both intra- and inter-family comparison of solvent system selectivity. Finally, 2-dimensional reciprocal shifted symmetry plots (ReSS(2)) were created to visually compare both the polarities and selectivities of solvent system pairs. This study helps to pave the way to the development of new solvent systems that are amenable to successive orthogonal CS protocols employed in metabolomic studies. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Measurement of genotoxic air pollutant exposures in street vendors and school children in and near Bangkok

    International Nuclear Information S