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Sample records for human exposure study

  1. A radiopharmacological study without human radiation exposure

    International Nuclear Information System (INIS)

    Loew, D.; Graul, E.H.; Kunkel, R.

    1984-01-01

    The development, study and control of new drugs today is hardly conceivable without nuclear medicine studies. Nuclear physicians on ethical commissions bear great responsibility in the planning and execution of such studies. In order to protect subjects and patients those nuclear techniques are therefore to be welcome which do not include exposure to radiation. Nuclear techniques used in in-vitro diagnostics (RIA) and the determination of naturally occurring nuclides incorporated in the human body belong to this category. With the aid of a clinico-pharmacological study of a new combination of diuretics it is shown that both methods supply valuable pharmacodynamic evidence. (orig.) [de

  2. Consolidated Human Activity Database (CHAD) for use in human exposure and health studies and predictive models

    Science.gov (United States)

    EPA scientists have compiled detailed data on human behavior from 22 separate exposure and time-use studies into CHAD. The database includes more than 54,000 individual study days of detailed human behavior.

  3. Assessment of human exposures

    Energy Technology Data Exchange (ETDEWEB)

    Lebret, E [RIVM-National Inst. of Public Health and Environmental Protection (Netherlands)

    1996-12-31

    This article describes some of the features of the assessment of human exposure to environmental pollutants in epidemiological studies. Since exposure assessment in air pollution epidemiology studies typically involve professionals from various backgrounds, interpretation of a concepts like `exposure` may vary. A brief descriptions is therefore given by way of introduction

  4. Assessment of human exposures

    Energy Technology Data Exchange (ETDEWEB)

    Lebret, E. [RIVM-National Inst. of Public Health and Environmental Protection (Netherlands)

    1995-12-31

    This article describes some of the features of the assessment of human exposure to environmental pollutants in epidemiological studies. Since exposure assessment in air pollution epidemiology studies typically involve professionals from various backgrounds, interpretation of a concepts like `exposure` may vary. A brief descriptions is therefore given by way of introduction

  5. Human immunotoxicologic markers of chemical exposures: preliminary validation studies.

    Science.gov (United States)

    Wartenberg, D; Laskin, D; Kipen, H

    1993-01-01

    The circulating cells of the immune system are sensitive to environmental contaminants, and effects are often manifested as changes in the cell surface differentiation antigens of affected populations of cells, particularly lymphocytes. In this investigation, we explore the likelihood that variation in the expression of the surface markers of immune cells can be used as an index of exposure to toxic chemicals. We recruited 38 healthy New Jersey men to study pesticides effects: 19 orchard farmers (high exposure); 13 berry farmers (low exposure); and 6 hardware store owners (no exposure). Immunophenotyping was performed assaying the following cell surface antigens: CD2, CD4, CD8, CD14, CD20, CD26, CD29, CD45R, CD56, and PMN. Data were analyzed using univariate and multivariate methods. There were no significant differences among the groups with respect to routine medical histories, physical examinations, or routine laboratory parameters. No striking differences between groups were seen in univariate tests. Multivariate tests suggested some differences among groups and limited ability to correctly classify individuals based on immunophenotyping results. Immunophenotyping represents a fruitful area of research for improved exposure classification. Work is needed both on mechanistic understanding of the patterns observed and on the statistical interpretation of these patterns.

  6. Human volunteer study with PGME: Eye irritation during vapour exposure

    NARCIS (Netherlands)

    Emmen, H.H.; Muijser, H.; Arts, J.H.E.; Prinsen, M.K.

    2003-01-01

    The objective of this study was to establish the possible occurrence of eye irritation and subjective symptoms in human volunteers exposed to propylene glycol monomethyl ether (PGME) vapour at concentrations of 0, 100 and 150 ppm. Testing was conducted in 12 healthy male volunteers using a repeated

  7. Application of human volunteer studies in setting exposure limits

    International Nuclear Information System (INIS)

    Bailey, M.R.

    1989-01-01

    Human volunteer studies can provide many of the quantitative data on human radionuclide biokinetics needed to relate organ doses to intakes. They are best suited to characterising parameters that apply to a wide range of compounds, e.g. particle deposition in the respiratory tract, and the retention and excretion of elements after injection into the blood. Their application to quantifying particle clearance from the respiratory tract is discussed, with particular reference to recent findings and the NRPB's programme of volunteer investigations. Evidence to support the view that particle clearance rates are similar for different materials is summarised. Rates of particle clearance from the human lung to the GI tract are calculated from the results of two recent studies. The fraction of the remaining lung content cleared per day is estimated to decrease from ∼ 3 x 10 -3 d -1 at 25 days to ∼ 5 x 10 -4 d -1 at 350 days. There is a large degree of inter-subject variation, with most results conforming to a log-normal distribution with σ g of 1.6. There remains considerable uncertainty about subsequent clearance, and about sites of long-term lung retention. (author)

  8. The human placenta--an alternative for studying foetal exposure

    DEFF Research Database (Denmark)

    Myren, Maja; Mose, Tina; Mathiesen, Line

    2007-01-01

    Pregnant women are daily exposed to a wide selection of foreign substances. Sources are as different as lifestyle factors (smoking, daily care products, alcohol consumption, etc.), maternal medication or occupational/environmental exposures. The placenta provides the link between mother and foetus......, and though its main task is to act as a barrier and transport nutrients and oxygen to the foetus, many foreign compounds are transported across the placenta to some degree and may therefore influence the unborn child. Foetal exposures to environmental and medicinal products may have impact on the growth...... of the foetus (e.g. cigarette smoke) and development of the foetal organs (e.g. methylmercury and thalidomide). The scope of this review is to give insight to the placental anatomy, development and function. Furthermore, the compounds physical properties and the transfer mechanism across the placental barrier...

  9. Human Exposure and Health

    Science.gov (United States)

    The ROE is divided into 5 themes: Air, Water, Land, Human Exposure and Health and Ecological Condition. From these themes, the report indicators address fundamental questions that the ROE attempts to answer. For human health there are 3 questions.

  10. Human exposure to nickel

    Energy Technology Data Exchange (ETDEWEB)

    Grandjean, P

    1984-01-01

    In order of abundance in the earth's crust, nickel ranks as the 24th element and has been detected in different media in all parts of the biosphere. Thus, humans are constantly exposed to this ubiquitous element, though in variable amounts. Occupational exposures may lead to the retention of 100 micrograms of nickel per day. Environmental nickel levels depend particularly on natural sources, pollution from nickel-manufacturing industries and airborne particles from combustion of fossil fuels. Absorption from atmospheric nickel pollution is of minor concern. Vegetables usually contain more nickel than do other food items. Certain products, such as baking powder and cocoa powder, have been found to contain excessive amounts of nickel, perhaps related to nickel leaching during the manufacturing process. Soft drinking-water and acid beverages may dissolve nickel from pipes and containers. Scattered studies indicate a highly variable dietary intake of nickel, but most averages are about 200-300 micrograms/day. In addition, skin contact to a multitude of metal objects may be of significance to the large number of individuals suffering from contact dermatitis and nickel allergy. Finally, nickel alloys are often used in nails and prostheses for orthopaedic surgery, and various sources may contaminate intravenous fluids. Thus, human nickel exposure originates from a variety of sources and is highly variable. Occupational nickel exposure is of major significance, and leaching of nickel may add to dietary intakes and to cutaneous exposures. 79 references.

  11. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    International Nuclear Information System (INIS)

    Fabrikant, J.I.

    1981-05-01

    The current knowledge of the carcinogenic effect of radiation in man is considered. The discussion is restricted to dose-incidence data in humans, particularly to certain of those epidemiological studies of human populations that are used most frequently for risk estimation for low-dose radiation carcinogenesis in man. Emphasis is placed solely on those surveys concerned with nuclear explosions and medical exposures

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

    International Nuclear Information System (INIS)

    Legros, A.; Corbacio, M.; Prato, F.S.; Thomas, A.W.; Beuter, A.; Goulet, D.; Lambrozo, J.; Souques, M.; Plante, M.

    2010-01-01

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

  13. Neuromotor effects of acute ethanol inhalation exposure in humans: a preliminary study.

    Science.gov (United States)

    Nadeau, Véronique; Lamoureux, Daniel; Beuter, Anne; Charbonneau, Michel; Tardif, Robert

    2003-07-01

    Ethanol (ETOH) is added to unleaded gasoline to decrease environmental levels of carbon monoxide from automobiles emissions. Therefore, addition of ETOH in reformulated fuel will most likely increase and the involuntarily human exposure to this chemical will also increase. This preliminary study was undertaken to evaluate the possible neuromotor effects resulting from acute ETOH exposure by inhalation in humans. Five healthy non-smoking adult males, with no history of alcohol abuse, were exposed by inhalation, in a dynamic, controlled-environment exposure chamber, to various concentrations of ETOH (0, 250, 500 and 1,000 ppm in air) for six hours. Reaction time, body sway, hand tremor and rapid alternating movements were measured before and after each exposure session by using the CATSYS 7.0 system and a diadochokinesimeter. The concentrations of ETOH in blood and in alveolar air were also measured. ETOH was not detected in blood nor in alveolar air when volunteers were exposed to 250 and 500 ppm, but at the end of exposure to 1,000 ppm, blood and alveolar air concentrations were 0.443 mg/100ml and 253.1 ppm, respectively. The neuromotor tests did not show conclusively significant differences between the exposed and non-exposed conditions. In conclusion, this study suggests that acute exposure to ethanol at 1,000 ppm or lower or to concentrations that could be encountered upon refueling is not likely to cause any significant neuromotor alterations in healthy males.

  14. Ozone exposure and pulmonary effects in panel and human clinical studies: Considerations for design and interpretation.

    Science.gov (United States)

    Rohr, Annette C

    2018-04-01

    A wealth of literature exists regarding the pulmonary effects of ozone, a photochemical pollutant produced by the reaction of nitrogen oxide and volatile organic precursors in the presence of sunlight. This paper focuses on epidemiological panel studies and human clinical studies of ozone exposure, and discusses issues specific to this pollutant that may influence study design and interpretation as well as other, broader considerations relevant to ozone-health research. The issues are discussed using examples drawn from the wider literature. The recent panel and clinical literature is also reviewed. Health outcomes considered include lung function, symptoms, and pulmonary inflammation. Issues discussed include adversity, reversibility, adaptation, variability in ozone exposure metric used and health outcomes evaluated, co-pollutants in panel studies, influence of temperature in panel studies, and multiple comparisons. Improvements in and standardization of panel study approaches are recommended to facilitate comparisons between studies as well as meta-analyses. Additional clinical studies at or near the current National Ambient Air Quality Standard (NAAQS) of 70 ppb are recommended, as are clinical studies in sensitive subpopulations such as asthmatics. The pulmonary health impacts of ozone exposure have been well documented using both epidemiological and chamber study designs. However, there are a number of specific methodological and related issues that should be considered when interpreting the results of these studies and planning additional research, including the standardization of exposure and health metrics to facilitate comparisons among studies.

  15. Human exposure to aluminium.

    Science.gov (United States)

    Exley, Christopher

    2013-10-01

    Human activities have circumvented the efficient geochemical cycling of aluminium within the lithosphere and therewith opened a door, which was previously only ajar, onto the biotic cycle to instigate and promote the accumulation of aluminium in biota and especially humans. Neither these relatively recent activities nor the entry of aluminium into the living cycle are showing any signs of abating and it is thus now imperative that we understand as fully as possible how humans are exposed to aluminium and the future consequences of a burgeoning exposure and body burden. The aluminium age is upon us and there is now an urgent need to understand how to live safely and effectively with aluminium.

  16. Mercury Exposure in Ireland: Results of the DEMOCOPHES Human Biomonitoring Study

    Directory of Open Access Journals (Sweden)

    Elizabeth Cullen

    2014-09-01

    Full Text Available Background: Monitoring of human exposure to mercury is important due to its adverse health effects. This study aimed to determine the extent of mercury exposure among mothers and their children in Ireland, and to identify factors associated with elevated levels. It formed part of the Demonstration of a study to Coordinate and Perform Human Biomonitoring on a European Scale (DEMOCOPHES pilot biomonitoring study. Methods: Hair mercury concentrations were determined from a convenience sample of 120 mother/child pairs. Mothers also completed a questionnaire. Rigorous quality assurance within DEMOCOPHES guaranteed the accuracy and international comparability of results. Results: Mercury was detected in 79.2% of the samples from mothers, and 62.5% of children’s samples. Arithmetic mean levels in mothers (0.262 µg/g hair and children (0.149 µg /g hair did not exceed the US EPA guidance value. Levels were significantly higher for those with higher education, and those who consumed more fish. Conclusions: The study demonstrates the benefit of human biomonitoring for assessing and comparing internal exposure levels, both on a population and an individual basis. It enables the potential harmful impact of mercury to be minimised in those highly exposed, and can therefore significantly contribute to population health.

  17. Risk of human exposure to polycyclic aromatic hydrocarbons: A case study in Beijing, China

    International Nuclear Information System (INIS)

    Yu, Yanxin; Li, Qi; Wang, Hui; Wang, Bin; Wang, Xilong; Ren, Aiguo; Tao, Shu

    2015-01-01

    Polycyclic aromatic hydrocarbons (PAHs) can cause adverse effects on human health. The relative contributions of their two major intake routes (diet and inhalation) to population PAH exposure are still unclear. We modeled the contributions of diet and inhalation to the overall PAH exposure of the population of Beijing in China, and assessed their human incremental lifetime cancer risks (ILCR) using a Mont Carlo simulation approach. The results showed that diet accounted for about 85% of low-molecular-weight PAH (L-PAH) exposure, while inhalation accounted for approximately 57% of high-molecular-weight PAH (H-PAH) exposure of the Beijing population. Meat and cereals were the main contributors to dietary PAH exposure. Both gaseous- and particulate-phase PAHs contributed to L-PAH exposure through inhalation, whereas exposure to H-PAHs was mostly from the particulate-phase. To reduce the cancer incidence of the Beijing population, more attention should be given to inhaled particulate-phase PAHs with considerable carcinogenic potential. - Highlights: • We modeled the contributions of diet and inhalation to population PAH exposure. • Diet contributed 85% of population exposure to low molecular-weight PAHs. • Inhalation contributed 57% of population exposure to high molecular-weight PAHs. • The PAH exposure level with body-weight adjustment decreased with age increasing. • The population cancer risk of PAH exposure is lower than the serious risk level. - The exposure of the Beijing population to carcinogenic polycyclic aromatic hydrocarbons was mainly from inhaled particulate matter

  18. The use of biomonitoring data in exposure and human health risk assessment: benzene case study

    OpenAIRE

    Arnold, Scott M.; Angerer, Juergen; Boogaard, Peter J.; Hughes, Michael F.; O?Lone, Raegan B.; Robison, Steven H.; Robert Schnatter, A.

    2013-01-01

    A framework of ?Common Criteria? (i.e. a series of questions) has been developed to inform the use and evaluation of biomonitoring data in the context of human exposure and risk assessment. The data-rich chemical benzene was selected for use in a case study to assess whether refinement of the Common Criteria framework was necessary, and to gain additional perspective on approaches for integrating biomonitoring data into a risk-based context. The available data for benzene satisfied most of th...

  19. The ethics of human volunteer studies involving experimental exposure to pesticides: unanswered dilemmas

    Directory of Open Access Journals (Sweden)

    London Leslie

    2010-08-01

    Full Text Available Abstract The controversy about the use of data from human volunteer studies involving experimental exposure to pesticides as part of regulatory risk assessment has been widely discussed, but the complex and interrelated scientific and ethical issues remain largely unresolved. This discussion paper, generated by authors who comprised a workgroup of the ICOH Scientific Committee on Rural Health, reviews the use of human experimental studies in regulatory risk assessment for pesticides with a view to advancing the debate as to when, if ever, such studies might be ethically justifiable. The discussion is based on three elements: (a a review of discussion papers on the topic of human testing of pesticides and the positions adopted by regulatory agencies in developed countries; (b an analysis of published and unpublished studies involving human testing with pesticides, both in the peer-reviewed literature and in the JMPR database; and (c application of an ethical analysis to the problem. The paper identifies areas of agreement which include general principles that may provide a starting point on which to base criteria for judgements as to the ethical acceptability of such studies. However, the paper also highlights ongoing unresolved differences of opinion inherent in ethical analysis of contentious issues, which we propose should form a starting point for further debate and the development of guidelines to achieve better resolution of this matter.

  20. The ethics of human volunteer studies involving experimental exposure to pesticides: unanswered dilemmas.

    Science.gov (United States)

    London, Leslie; Coggon, David; Moretto, Angelo; Westerholm, Peter; Wilks, Martin F; Colosio, Claudio

    2010-08-18

    The controversy about the use of data from human volunteer studies involving experimental exposure to pesticides as part of regulatory risk assessment has been widely discussed, but the complex and interrelated scientific and ethical issues remain largely unresolved. This discussion paper, generated by authors who comprised a workgroup of the ICOH Scientific Committee on Rural Health, reviews the use of human experimental studies in regulatory risk assessment for pesticides with a view to advancing the debate as to when, if ever, such studies might be ethically justifiable. The discussion is based on three elements: (a) a review of discussion papers on the topic of human testing of pesticides and the positions adopted by regulatory agencies in developed countries; (b) an analysis of published and unpublished studies involving human testing with pesticides, both in the peer-reviewed literature and in the JMPR database; and (c) application of an ethical analysis to the problem. The paper identifies areas of agreement which include general principles that may provide a starting point on which to base criteria for judgements as to the ethical acceptability of such studies. However, the paper also highlights ongoing unresolved differences of opinion inherent in ethical analysis of contentious issues, which we propose should form a starting point for further debate and the development of guidelines to achieve better resolution of this matter.

  1. The ethics of human volunteer studies involving experimental exposure to pesticides: unanswered dilemmas

    Science.gov (United States)

    2010-01-01

    The controversy about the use of data from human volunteer studies involving experimental exposure to pesticides as part of regulatory risk assessment has been widely discussed, but the complex and interrelated scientific and ethical issues remain largely unresolved. This discussion paper, generated by authors who comprised a workgroup of the ICOH Scientific Committee on Rural Health, reviews the use of human experimental studies in regulatory risk assessment for pesticides with a view to advancing the debate as to when, if ever, such studies might be ethically justifiable. The discussion is based on three elements: (a) a review of discussion papers on the topic of human testing of pesticides and the positions adopted by regulatory agencies in developed countries; (b) an analysis of published and unpublished studies involving human testing with pesticides, both in the peer-reviewed literature and in the JMPR database; and (c) application of an ethical analysis to the problem. The paper identifies areas of agreement which include general principles that may provide a starting point on which to base criteria for judgements as to the ethical acceptability of such studies. However, the paper also highlights ongoing unresolved differences of opinion inherent in ethical analysis of contentious issues, which we propose should form a starting point for further debate and the development of guidelines to achieve better resolution of this matter. PMID:20718963

  2. Multi-platform metabolomics assays for human lung lavage fluids in an air pollution exposure study.

    Science.gov (United States)

    Surowiec, Izabella; Karimpour, Masoumeh; Gouveia-Figueira, Sandra; Wu, Junfang; Unosson, Jon; Bosson, Jenny A; Blomberg, Anders; Pourazar, Jamshid; Sandström, Thomas; Behndig, Annelie F; Trygg, Johan; Nording, Malin L

    2016-07-01

    Metabolomics protocols are used to comprehensively characterize the metabolite content of biological samples by exploiting cutting-edge analytical platforms, such as gas chromatography (GC) or liquid chromatography (LC) coupled to mass spectrometry (MS) assays, as well as nuclear magnetic resonance (NMR) assays. We have developed novel sample preparation procedures combined with GC-MS, LC-MS, and NMR metabolomics profiling for analyzing bronchial wash (BW) and bronchoalveolar lavage (BAL) fluid from 15 healthy volunteers following exposure to biodiesel exhaust and filtered air. Our aim was to investigate the responsiveness of metabolite profiles in the human lung to air pollution exposure derived from combustion of biofuels, such as rapeseed methyl ester biodiesel, which are increasingly being promoted as alternatives to conventional fossil fuels. Our multi-platform approach enabled us to detect the greatest number of unique metabolites yet reported in BW and BAL fluid (82 in total). All of the metabolomics assays indicated that the metabolite profiles of the BW and BAL fluids differed appreciably, with 46 metabolites showing significantly different levels in the corresponding lung compartments. Furthermore, the GC-MS assay revealed an effect of biodiesel exhaust exposure on the levels of 1-monostearylglycerol, sucrose, inosine, nonanoic acid, and ethanolamine (in BAL) and pentadecanoic acid (in BW), whereas the LC-MS assay indicated a shift in the levels of niacinamide (in BAL). The NMR assay only identified lactic acid (in BW) as being responsive to biodiesel exhaust exposure. Our findings demonstrate that the proposed multi-platform approach is useful for wide metabolomics screening of BW and BAL fluids and can facilitate elucidation of metabolites responsive to biodiesel exhaust exposure. Graphical Abstract Graphical abstract illustrating the study workflow. NMR Nuclear Magnetic Resonance, LC-TOFMS Liquid chromatography-Time Of Flight Mass Spectrometry, GC Gas

  3. Dietary exposure and human risk assessment of phthalate esters based on total diet study in Cambodia

    International Nuclear Information System (INIS)

    Cheng, Zhang; Li, Han-Han; Wang, Hong-sheng; Zhu, Xue-Mei; Sthiannopkao, Suthipong; Kim, Kyoung-Woong; Yasin, Mohamed Salleh Mohamed; Hashim, Jamal Hisham; Wong, Ming-Hung

    2016-01-01

    Phthalate esters are used in a wide variety of consumer products, and human exposure to this class of compounds is widespread. Nevertheless, studies on dietary exposure of human to phthalates are limited. In this study, to assess the daily intakes of phthalate esters and the possible adverse health impacts, different food samples were collected from three areas of Cambodia, one of the poorest countries in the world. The ∑phthalate ester concentrations in Kampong Cham, Kratie and Kandal provinces ranged from 0.05 to 2.34 (median 0.88) μg g −1 , 0.19–1.65 (median 0.86) μg g −1 and 0.24–3.05 (median 0.59) μg g −1 wet weight (ww), respectively. Di-2-Ethylhexyl phthalate (DEHP) and diisobutyl phthalate (DiBP) were the predominant compounds among all foodstuffs. The estimated daily intake (EDI) of phthalate esters for the general population in Kampong Cham, Kratie and Kandal was 34.3, 35.6 and 35.8 μg kg −1 bw d −1 , respectively. The dietary daily intake of DEHP, benzylbutyl phthalate (BBP) and di-n-butyl phthalate (DBP) in Kampong Cham, Kratie and Kandal were below the tolerable daily intakes (TDI) imposed by the European Food Safety Authority (EFSA) and reference doses (RfD) imposed by The United States Environmental Protection Agency (USEPA). Rice contributed the greatest quantity of DEHP to the daily intake in Cambodia so may deserve further exploration. To our knowledge, this is the first study to investigate the occurrence and the daily intakes of phthalate esters in Cambodia. - Highlights: • Phthalate esters concentration in daily foodstuffs collected from Cambodia. • Investigate the bioaccessbility of phthalate esters via the foodstuffs consumption. • Health risk evaluation of dietary exposure to phthalate esters.

  4. Dietary exposure and human risk assessment of phthalate esters based on total diet study in Cambodia

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Zhang; Li, Han-Han [College of Environment, Sichuan Agricultural University, Chengdu 611130 (China); Wang, Hong-sheng [Department of Microbial and Biochemical Pharmacy, School of Pharmaceutical Sciences, Sun Yat-sen University, No.132 Waihuandong Road, University Town, Guangzhou 510006 (China); Zhu, Xue-Mei [College of Environment, Sichuan Agricultural University, Chengdu 611130 (China); Sthiannopkao, Suthipong [Department of Environmental and Occupational Health, National Cheng Kung University, Tainan City, Taiwan (China); Kim, Kyoung-Woong [School of Environmental Science and Engineering, Gwangju Institute of Science and Technology, Gwangju (Korea, Republic of); Yasin, Mohamed Salleh Mohamed; Hashim, Jamal Hisham [United Nations University-International Institute for Global Health, Kuala Lumpur (Malaysia); Wong, Ming-Hung, E-mail: minghwong@ied.edu.hk [Consortium on Health, Environment, Education and Research (CHEER), and Department of Science and Environmental Studies, Hong Kong Institute of Education, Tai Po, Hong Kong (China); School of Environment, Jinan University, Guangzhou (China)

    2016-10-15

    Phthalate esters are used in a wide variety of consumer products, and human exposure to this class of compounds is widespread. Nevertheless, studies on dietary exposure of human to phthalates are limited. In this study, to assess the daily intakes of phthalate esters and the possible adverse health impacts, different food samples were collected from three areas of Cambodia, one of the poorest countries in the world. The ∑phthalate ester concentrations in Kampong Cham, Kratie and Kandal provinces ranged from 0.05 to 2.34 (median 0.88) μg g{sup −1}, 0.19–1.65 (median 0.86) μg g{sup −1} and 0.24–3.05 (median 0.59) μg g{sup −1} wet weight (ww), respectively. Di-2-Ethylhexyl phthalate (DEHP) and diisobutyl phthalate (DiBP) were the predominant compounds among all foodstuffs. The estimated daily intake (EDI) of phthalate esters for the general population in Kampong Cham, Kratie and Kandal was 34.3, 35.6 and 35.8 μg kg{sup −1} bw d{sup −1}, respectively. The dietary daily intake of DEHP, benzylbutyl phthalate (BBP) and di-n-butyl phthalate (DBP) in Kampong Cham, Kratie and Kandal were below the tolerable daily intakes (TDI) imposed by the European Food Safety Authority (EFSA) and reference doses (RfD) imposed by The United States Environmental Protection Agency (USEPA). Rice contributed the greatest quantity of DEHP to the daily intake in Cambodia so may deserve further exploration. To our knowledge, this is the first study to investigate the occurrence and the daily intakes of phthalate esters in Cambodia. - Highlights: • Phthalate esters concentration in daily foodstuffs collected from Cambodia. • Investigate the bioaccessbility of phthalate esters via the foodstuffs consumption. • Health risk evaluation of dietary exposure to phthalate esters.

  5. The use of biomonitoring data in exposure and human health risk assessment: benzene case study.

    Science.gov (United States)

    Arnold, Scott M; Angerer, Juergen; Boogaard, Peter J; Hughes, Michael F; O'Lone, Raegan B; Robison, Steven H; Schnatter, A Robert

    2013-02-01

    Abstract A framework of "Common Criteria" (i.e. a series of questions) has been developed to inform the use and evaluation of biomonitoring data in the context of human exposure and risk assessment. The data-rich chemical benzene was selected for use in a case study to assess whether refinement of the Common Criteria framework was necessary, and to gain additional perspective on approaches for integrating biomonitoring data into a risk-based context. The available data for benzene satisfied most of the Common Criteria and allowed for a risk-based evaluation of the benzene biomonitoring data. In general, biomarker (blood benzene, urinary benzene and urinary S-phenylmercapturic acid) central tendency (i.e. mean, median and geometric mean) concentrations for non-smokers are at or below the predicted blood or urine concentrations that would correspond to exposure at the US Environmental Protection Agency reference concentration (30 µg/m(3)), but greater than blood or urine concentrations relating to the air concentration at the 1 × 10(-5) excess cancer risk (2.9 µg/m(3)). Smokers clearly have higher levels of benzene exposure, and biomarker levels of benzene for non-smokers are generally consistent with ambient air monitoring results. While some biomarkers of benzene are specific indicators of exposure, the interpretation of benzene biomonitoring levels in a health-risk context are complicated by issues associated with short half-lives and gaps in knowledge regarding the relationship between the biomarkers and subsequent toxic effects.

  6. The use of biomonitoring data in exposure and human health risk assessment: benzene case study

    Science.gov (United States)

    Angerer, Juergen; Boogaard, Peter J.; Hughes, Michael F.; O’Lone, Raegan B.; Robison, Steven H.; Robert Schnatter, A.

    2013-01-01

    A framework of “Common Criteria” (i.e. a series of questions) has been developed to inform the use and evaluation of biomonitoring data in the context of human exposure and risk assessment. The data-rich chemical benzene was selected for use in a case study to assess whether refinement of the Common Criteria framework was necessary, and to gain additional perspective on approaches for integrating biomonitoring data into a risk-based context. The available data for benzene satisfied most of the Common Criteria and allowed for a risk-based evaluation of the benzene biomonitoring data. In general, biomarker (blood benzene, urinary benzene and urinary S-phenylmercapturic acid) central tendency (i.e. mean, median and geometric mean) concentrations for non-smokers are at or below the predicted blood or urine concentrations that would correspond to exposure at the US Environmental Protection Agency reference concentration (30 µg/m3), but greater than blood or urine concentrations relating to the air concentration at the 1 × 10−5 excess cancer risk (2.9 µg/m3). Smokers clearly have higher levels of benzene exposure, and biomarker levels of benzene for non-smokers are generally consistent with ambient air monitoring results. While some biomarkers of benzene are specific indicators of exposure, the interpretation of benzene biomonitoring levels in a health-risk context are complicated by issues associated with short half-lives and gaps in knowledge regarding the relationship between the biomarkers and subsequent toxic effects. PMID:23346981

  7. Mercury in human brain, blood, muscle and toenails in relation to exposure: an autopsy study

    Directory of Open Access Journals (Sweden)

    Morild Inge

    2007-10-01

    Full Text Available Abstract Background The main forms of mercury (Hg exposure in the general population are methylmercury (MeHg from seafood, inorganic mercury (I-Hg from food, and mercury vapor (Hg0 from dental amalgam restorations. While the distribution of MeHg in the body is described by a one compartment model, the distribution of I-Hg after exposure to elemental mercury is more complex, and there is no biomarker for I-Hg in the brain. The aim of this study was to elucidate the relationships between on the one hand MeHg and I-Hg in human brain and other tissues, including blood, and on the other Hg exposure via dental amalgam in a fish-eating population. In addition, the use of blood and toenails as biological indicator media for inorganic and organic mercury (MeHg in the tissues was evaluated. Methods Samples of blood, brain (occipital lobe cortex, pituitary, thyroid, abdominal muscle and toenails were collected at autopsy of 30 deceased individuals, age from 47 to 91 years of age. Concentrations of total-Hg and I-Hg in blood and brain cortex were determined by cold vapor atomic fluorescence spectrometry and total-Hg in other tissues by sector field inductively coupled plasma-mass spectrometry (ICP-SFMS. Results The median concentrations of MeHg (total-Hg minus I-Hg and I-Hg in blood were 2.2 and 1.0 μg/L, and in occipital lobe cortex 4 and 5 μg/kg, respectively. There was a significant correlation between MeHg in blood and occipital cortex. Also, total-Hg in toenails correlated with MeHg in both blood and occipital lobe. I-Hg in both blood and occipital cortex, as well as total-Hg in pituitary and thyroid were strongly associated with the number of dental amalgam surfaces at the time of death. Conclusion In a fish-eating population, intake of MeHg via the diet has a marked impact on the MeHg concentration in the brain, while exposure to dental amalgam restorations increases the I-Hg concentrations in the brain. Discrimination between mercury species is

  8. Studies on chromosome aberrations induced in human lymphocytes by very low-dose exposure to tritium

    International Nuclear Information System (INIS)

    Hori, T.; Moriya, Junko; Nakai, Sayaka

    1978-01-01

    Assessment of potential hazard from environmental tritium to man becomes very important with increasing the development of nuclear-power industry. However, little data are available as to the determination on the genetic effect of tritium especially at the low levels. The object of the present study is to obtain quantitative data for chromosome aberrations in human lymphocytes, as an indicator for genetic risk estimation, induced by tritium at very low dose levels. Leukocyte cultures of human peripheral blood were chronically exposed for 48h to tritiated water and 3 H-thymidine using a wide range of tritium doses, and aberrations in lymphocyte chromosomes at the first metaphases were examined. In the experimental conditions, the types of aberrations induced by radiation emitted from both tritiated water and 3 H-thymidine were mostly chromatid types, such as chromatid gaps and deletions. The dose-response relations for chromatid breaks per cell exhibited unusual dose-dependency in both cases. It was demonstrated that at higher dose range the yields of chromatid breaks increased linearly with dose, while those at lower dose range were significantly higher than would be expected by a downward extraporation from the linear relation. Partial-hit or partial-target kinetics events appeared at very low dose exposure. (author)

  9. [Study of work accidents related to human body fluids exposure among health workers at a university hospital].

    Science.gov (United States)

    Balsamo, Ana Cristina; Felli, Vanda Elisa Andres

    2006-01-01

    This descriptive and exploratory study from a quantitative approach aimed to characterize workers who were victims of work accidents related to human body fluids exposure and to evaluate the accident victim care protocol. The population consisted of 48 workers who were victims of work accidents involving exposure to human body fluids, from July 2000 to June 2001. Data were collected through a form and interviews. Results showed that nursing workers presented higher accident risk levels and that 87.50% involved piercing and cutting material, such as needles and butterflies (70%). As to the accident-related situation/activity, the workers indicated that 25% were due to an "inadequate act during the procedure"; 19.64% mentioned that "it happened" and 29.17% answered that they did not have any suggestion. This study provided important tools to review and elaborate strategies to prevent accidents involving exposure to human body fluids.

  10. Use of human metabolic studies and urinary arsenic speciation is assessing arsenic exposure

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L.R.; Farmer, J.G. (Memphis State Univ., TN (United States) Univ. of Edinburgh (United Kingdom))

    1991-01-01

    The use of hair and nail analyses to assess human exposure to the trace metalloid arsenic (As) is hindered by the possibility of external contamination. Even though urine represents the major excretory route, its use as an indicator of exposure is limited when no distinction is made between the nontoxic organoarsenical (arsenobetaine) excreted following the consumption of seafood and the toxic inorganic forms of As and related metabolites. The development of analytical techniques capable of separating the different chemical species of As in urine have shown that the ingestion of inorganic As (AsV or AsIII) by animals and man triggers an in vivo reduction/methylation process resulting in excretion of the less toxic species, monomethylarsonic acid (MMAA) and dimethylarsinic acid (DMAA). This paper establishes the uptake, bio-transformation and elimination patterns reflected in urinary As following carefully controlled experimental exposure.

  11. Identification of fipronil metabolites by time-of-flight mass spectrometry for application in a human exposure study.

    Science.gov (United States)

    McMahen, Rebecca L; Strynar, Mark J; Dagnino, Sonia; Herr, David W; Moser, Virginia C; Garantziotis, Stavros; Andersen, Erik M; Freeborn, Danielle L; McMillan, Larry; Lindstrom, Andrew B

    2015-05-01

    Fipronil is a phenylpyrazole insecticide commonly used in residential and agricultural applications. To understand more about the potential risks for human exposure associated with fipronil, urine and serum from dosed Long Evans adult rats (5 and 10mg/kg bw) were analyzed to identify metabolites as potential biomarkers for use in human biomonitoring studies. Urine from treated rats was found to contain seven unique metabolites, two of which had not been previously reported-M4 and M7 which were putatively identified as a nitroso compound and an imine, respectively. Fipronil sulfone was confirmed to be the primary metabolite in rat serum. The fipronil metabolites identified in the respective matrices were then evaluated in matched human urine (n=84) and serum (n=96) samples from volunteers with no known pesticide exposures. Although no fipronil or metabolites were detected in human urine, fipronil sulfone was present in the serum of approximately 25% of the individuals at concentrations ranging from 0.1 to 4ng/mL. These results indicate that many fipronil metabolites are produced following exposures in rats and that fipronil sulfone is a useful biomarker in human serum. Furthermore, human exposure to fipronil may occur regularly and require more extensive characterization. Published by Elsevier Ltd.

  12. Effect of low and chronic radiation exposure to human population: Kollam study

    International Nuclear Information System (INIS)

    Ghosh, Anu; Kumar, Vinay

    2018-01-01

    Understanding the cellular and biological processes with low-level chronic radiation provides a rational basis for limits of exposure for occupational workers and general public. There are several high level natural radiation areas (HLNRA) of the world where human population is continuously exposed to natural radiation higher than the global average of 2.4 mGy/y. These areas provide unique opportunities to conduct studies which can provide better understanding of radiation effects and underlying mechanisms. The ∼55 km long monazite bearing belt of Kerala on the south-west coast of India is one such area. Over the last few decades, Bhabha Atomic Research Centre (BARC) has conducted extensive research on the human population residing in these areas to understand effects of low dose at the organismal, cellular and molecular levels. More recently, high resolution quantitative proteomic analysis of PBMCs using iTRAQ based LC-MS/MS identified differential expression of 1570 proteins in HLNRA individuals relative to individuals from the adjoining Normal Level Natural Radiation Areas (NLNRA). Almost 215 biological processes were distinctly altered in HLNRA samples, which included several pro-survival stress activated protein kinases and DNA repair networks. Many of the changes seen at the proteomics level were confirmed at the gene level using microarray expression data. This suggests an enhanced level of basal repair mechanisms in HLNRA individuals. The scientific program at BARC thus, focuses on fundamental scientific understanding of the mechanisms cells use to sense, repair and adapt to low dose radiation. Implications of these cellular processes for low dose radiation risk estimation will be discussed. (author)

  13. Heavy Metal Exposure and Metabolic Syndrome: Evidence from Human and Model System Studies.

    Science.gov (United States)

    Planchart, Antonio; Green, Adrian; Hoyo, Cathrine; Mattingly, Carolyn J

    2018-03-01

    Metabolic syndrome (MS) describes the co-occurrence of conditions that increase one's risk for heart disease and other disorders such as diabetes and stroke. The worldwide increase in the prevalence of MS cannot be fully explained by lifestyle factors such as sedentary behavior and caloric intake alone. Environmental exposures, such as heavy metals, have been implicated, but results are conflicting and possible mechanisms remain unclear. To assess recent progress in determining a possible role between heavy metal exposure and MS, we reviewed epidemiological and model system data for cadmium (Cd), lead (Pb), and mercury (Hg) from the last decade. Data from 36 epidemiological studies involving 17 unique countries/regions and 13 studies leveraging model systems are included in this review. Epidemiological and model system studies support a possible association between heavy metal exposure and MS or comorbid conditions; however, results remain conflicting. Epidemiological studies were predominantly cross-sectional and collectively, they highlight a global interest in this question and reveal evidence of differential susceptibility by sex and age to heavy metal exposures. In vivo studies in rats and mice and in vitro cell-based assays provide insights into potential mechanisms of action relevant to MS including altered regulation of lipid and glucose homeostasis, adipogenesis, and oxidative stress. Heavy metal exposure may contribute to MS or comorbid conditions; however, available data are conflicting. Causal inference remains challenging as epidemiological data are largely cross-sectional; and variation in study design, including samples used for heavy metal measurements, age of subjects at which MS outcomes are measured; the scope and treatment of confounding factors; and the population demographics vary widely. Prospective studies, standardization or increased consistency across study designs and reporting, and consideration of molecular mechanisms informed by model

  14. Biomarkers of exposure in environment-wide association studies - Opportunities to decode the exposome using human biomonitoring data.

    Science.gov (United States)

    Steckling, Nadine; Gotti, Alberto; Bose-O'Reilly, Stephan; Chapizanis, Dimitris; Costopoulou, Danae; De Vocht, Frank; Garí, Mercè; Grimalt, Joan O; Heath, Ester; Hiscock, Rosemary; Jagodic, Marta; Karakitsios, Spyros P; Kedikoglou, Kleopatra; Kosjek, Tina; Leondiadis, Leondios; Maggos, Thomas; Mazej, Darja; Polańska, Kinga; Povey, Andrew; Rovira, Joaquim; Schoierer, Julia; Schuhmacher, Marta; Špirić, Zdravko; Stajnko, Anja; Stierum, Rob; Tratnik, Janja Snoj; Vassiliadou, Irene; Annesi-Maesano, Isabella; Horvat, Milena; Sarigiannis, Dimosthenis A

    2018-07-01

    The European Union's 7th Framework Programme (EU's FP7) project HEALS - Health and Environment-wide Associations based on Large Population Surveys - aims a refinement of the methodology to elucidate the human exposome. Human biomonitoring (HBM) provides a valuable tool for understanding the magnitude of human exposure from all pathways and sources. However, availability of specific biomarkers of exposure (BoE) is limited. The objective was to summarize the availability of BoEs for a broad range of environmental stressors and exposure determinants and corresponding reference and exposure limit values and biomonitoring equivalents useful for unraveling the exposome using the framework of environment-wide association studies (EWAS). In a face-to-face group discussion, scope, content, and structure of the HEALS deliverable "Guidelines for appropriate BoE selection for EWAS studies" were determined. An expert-driven, distributed, narrative review process involving around 30 individuals of the HEALS consortium made it possible to include extensive information targeted towards the specific characteristics of various environmental stressors and exposure determinants. From the resulting 265 page report, targeted information about BoE, corresponding reference values (e.g., 95th percentile or measures of central tendency), exposure limit values (e.g., the German HBM I and II values) and biomonitoring equivalents (BEs) were summarized and updated. 64 individual biological, chemical, physical, psychological and social environmental stressors or exposure determinants were included to fulfil the requirements of EWAS. The list of available BoEs is extensive with a number of 135; however, 12 of the stressors and exposure determinants considered do not leave any measurable specific substance in accessible body specimens. Opportunities to estimate the internal exposure stressors not (yet) detectable in human specimens were discussed. Data about internal exposures are useful to decode

  15. 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.

  16. A systematic review of Bisphenol A "low dose" studies in the context of human exposure: a case for establishing standards for reporting "low-dose" effects of chemicals.

    Science.gov (United States)

    Teeguarden, Justin G; Hanson-Drury, Sesha

    2013-12-01

    Human exposure to the chemical Bisphenol A is almost ubiquitous in surveyed industrialized societies. Structural features similar to estrogen confer the ability of Bisphenol A (BPA) to bind estrogen receptors, giving BPA membership in the group of environmental pollutants called endocrine disruptors. References by scientists, the media, political entities, and non-governmental organizations to many toxicity studies as "low dose" has led to the belief that exposure levels in these studies are similar to humans, implying that BPA is toxic to humans at current exposures. Through systematic, objective comparison of our current, and a previous compilation of the "low-dose" literature to multiple estimates of human external and internal exposure levels, we found that the "low-dose" moniker describes exposures covering 8-12 orders of magnitude, the majority (91-99% of exposures) being greater than the upper bound of human exposure in the general infant, child and adult U.S. Population. "low dose" is therefore a descriptor without specific meaning regarding human exposure. Where human exposure data are available, for BPA and other environmental chemicals, reference to toxicity study exposures by direct comparison to human exposure would be more informative, more objective, and less susceptible to misunderstanding. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Human exposure, health hazards, and environmental regulations

    International Nuclear Information System (INIS)

    Steinemann, Anne

    2004-01-01

    United States environmental regulations, intended to protect human health, generally fail to address major sources of pollutants that endanger human health. These sources are surprisingly close to us and within our control, such as consumer products and building materials that we use within our homes, workplaces, schools, and other indoor environments. Even though these indoor sources account for nearly 90% of our pollutant exposure, they are virtually unregulated by existing laws. Even pollutant levels found in typical homes, if found outdoors, would often violate federal environmental standards. This article examines the importance of human exposure as a way to understand and reduce effects of pollutants on human health. Results from exposure studies challenge traditional thinking about pollutant hazards, and reveal deficiencies in our patchwork of laws. And results from epidemiological studies, showing increases in exposure-related diseases, underscore the need for new protections. Because we cannot rely solely on regulations to protect us, and because health effects from exposures can develop insidiously, greater efforts are needed to reduce and prevent significant exposures before they occur. Recommendations include the development and use of safer alternatives to common products, public education on ways to reduce exposure, systematic monitoring of human exposure to pollutants, and a precautionary approach in decision-making

  18. A study of the comparison between human and animal excretion data following inhalation exposure to plutonium 238 oxide aerosols

    International Nuclear Information System (INIS)

    Moss, W.D.; Martinez, G.; Gautier, M.A.

    1985-01-01

    Bioassay urine samples obtained since 1971 from eight Los Alamos employees, accidentally exposed by inhalation to high-fired plutonium-238 oxide aerosols, were studied and compared with excretion data obtained from Beagle dogs exposed to /sup 238/PuO/sub 2/ aerosols. The early period Pu human excretion data from the inhalation exposure were unexpected and were unlike previously studied occupational exposure urinary data obtained at Los Alamos. The initial urine samples collected on day one were below the detection limits of the analytical method (0.01 pCi). Within thirty days, however, detectible concentrations of Pu were measured in the urine for several of the exposed personnel. The amounts of Pu excreted continued to increase in each of the cases throughout the first year and the individual patterns of Pu excretion were similar. The human urinary excretion data was compared with similar excretion data obtained from an animal study conducted by the Inhalation Toxicology Research Institute (Me81). In the animal study, Beagle dogs received inhalation exposure to one of three sizes of monodisperse of polydisperse aerosol of /sup 238/PuO/sub 2/. Periodic sacrifice of pairs of dogs during the 4 years after the inhalation exposure provided data on the retention, translocation and mode of excretion of /sup 238/Pu. The comparison of human and animal /sup 238/Pu excretion data supported the observation that the excretion data were similar between the two species and that the animal excretion models can be applied to predict the human /sup 238/Pu excretion following inhalation exposure to high-fired oxides of /sup 238/Pu

  19. Assessment of environmental exposure to mercury in selected human populations as studied by nuclear and other techniques

    International Nuclear Information System (INIS)

    1995-01-01

    A Co-ordinated Research Programme (CRP) on assessment of environmental exposure to mercury in selected human populations as studied by nuclear and other techniques was initiated by the IAEA in 1990. The purpose of this CRP is to promote national and regional studies to evaluate the exposure of selected population groups to mercury and methylmercury and to estimate potential risks in these groups. The programme is focused on the analysis of human head hair for the determination of mercury and methylmercury. The CRP has two main components: (i) identifying population groups that are at risk, and (ii) studying health effects in the exposed persons, particularly pregnant women and the babies born to them. This document reports the discussions held during the third Research Co-ordination Meeting (RCM) for the CRP which took place at the IAEA, Monaco Laboratory. (author)

  20. Gamma-ray energy absorption and exposure buildup factor studies in some human tissues with endometriosis

    Energy Technology Data Exchange (ETDEWEB)

    Kurudirek, Murat, E-mail: mkurudirek@gmail.co [Faculty of Science, Department of Physics, Ataturk University, 25240 Erzurum (Turkey); Dogan, Bekir [Faculty of Science, Department of Physics, Ataturk University, 25240 Erzurum (Turkey); Ingec, Metin [Faculty of Medicine, Department of Obstetrics and Gynecology, Ataturk University, 25240 Erzurum (Turkey); Ekinci, Neslihan; Ozdemir, Yueksel [Faculty of Science, Department of Physics, Ataturk University, 25240 Erzurum (Turkey)

    2011-02-15

    Human tissues with endometriosis have been analyzed in terms of energy absorption (EABF) and exposure (EBF) buildup factors using the five-parameter geometric progression (G-P) fitting formula in the energy region 0.015-15 MeV up to a penetration depth of 40 mfp (mean free path). Chemical compositions of the tissue samples were determined using a wavelength dispersive X-ray fluorescence spectrometer (WDXRFS). Possible conclusions were drawn due to significant variations in EABF and EBF for the selected tissues when photon energy, penetration depth and chemical composition changed. Buildup factors so obtained may be of use when the method of choice for treatment of endometriosis is radiotherapy.

  1. How Does Chronic Cigarette Smoke Exposure Affect Human Skin? A Global Proteomics Study in Primary Human Keratinocytes.

    Science.gov (United States)

    Rajagopalan, Pavithra; Nanjappa, Vishalakshi; Raja, Remya; Jain, Ankit P; Mangalaparthi, Kiran K; Sathe, Gajanan J; Babu, Niraj; Patel, Krishna; Cavusoglu, Nükhet; Soeur, Jeremie; Pandey, Akhilesh; Roy, Nita; Breton, Lionel; Chatterjee, Aditi; Misra, Namita; Gowda, Harsha

    2016-11-01

    Cigarette smoking has been associated with multiple negative effects on human skin. Long-term physiological effects of cigarette smoke are through chronic and not acute exposure. Molecular alterations due to chronic exposure to cigarette smoke remain unclear. Primary human skin keratinocytes chronically exposed to cigarette smoke condensate (CSC) showed a decreased wound-healing capacity with an increased expression of NRF2 and MMP9. Using quantitative proteomics, we identified 4728 proteins, of which 105 proteins were overexpressed (≥2-fold) and 41 proteins were downregulated (≤2-fold) in primary skin keratinocytes chronically exposed to CSC. We observed an alteration in the expression of several proteins involved in maintenance of epithelial barrier integrity, including keratin 80 (5.3 fold, p value 2.5 × 10 -7 ), cystatin A (3.6-fold, p value 3.2 × 10 -3 ), and periplakin (2.4-fold, p value 1.2 × 10 -8 ). Increased expression of proteins associated with skin hydration, including caspase 14 (2.2-fold, p value 4.7 × 10 -2 ) and filaggrin (3.6-fold, p value 5.4 × 10 -7 ), was also observed. In addition, we report differential expression of several proteins, including adipogenesis regulatory factor (2.5-fold, p value 1.3 × 10 -3 ) and histone H1.0 (2.5-fold, p value 6.3 × 10 -3 ) that have not been reported earlier. Bioinformatics analyses demonstrated that proteins differentially expressed in response to CSC are largely related to oxidative stress, maintenance of skin integrity, and anti-inflammatory responses. Importantly, treatment with vitamin E, a widely used antioxidant, could partially rescue adverse effects of CSC exposure in primary skin keratinocytes. The utility of antioxidant-based new dermatological formulations in delaying or preventing skin aging and oxidative damages caused by chronic cigarette smoke exposure warrants further clinical investigations and multi-omics research.

  2. Experimental study on human exposure to occupant generated pollutants in rooms with ductless personalized ventilation

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Bolashikov, Zhecho Dimitrov; Lu, Pengfei

    2014-01-01

    The performance of “ductless” personalized ventilation in conjunction with displacement ventilation with regard to exposure to different body bioeffluents was studied. Experiments were performed in a full-scale room furnished as a double office. Room air temperature was kept at 26 oC. Two breathing...... modes for the ductless personalized and displacement ventilation were tested. The location of the bioeffluent source affected the spread of body bioeffluents in the space. The ductless personalized ventilation provided cleaner air to both occupants than displacement ventilation alone. Occupants using...... the ”ductless” system will perceive the supplied air quality as superior compared to displacement ventilation alone....

  3. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    International Nuclear Information System (INIS)

    Fabrikant, J.I.

    1981-01-01

    The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain, for problems and difficulties in extrapolation from data obtained at high doses to low doses, and from animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy

  4. Exposure Setup and Dosimetry for a Study on Effects of Mobile Communication Signals on Human Hematopoietic Stem Cells in vitro

    Directory of Open Access Journals (Sweden)

    M. Rohland

    2017-09-01

    Full Text Available In this paper we describe the design of an exposure setup used to study possible non-thermal effects due to the exposure of human hematopoietic stem cells to GSM, UMTS and LTE mobile communication signals. The experiments are performed under fully blinded conditions in a TEM waveguide located inside an incubator to achieve defined environmental conditions as required for the living cells. Chamber slides containing the cells in culture medium are placed on the septum of the waveguide. The environmental and exposure parameters such as signal power, temperatures, relative humidity and CO2 content of the surrounding atmosphere are monitored permanently during the exposure experiment. The power of the exposure signals required to achieve specific absorption rates of 0.5, 1, 2 and 4 W kg−1 are determined by numerical calculation of the field distribution inside the cell culture medium at 900 MHz (GSM, 1950 MHz (UMTS and 2535 MHz (LTE. The dosimetry is verified both with scattering parameter measurements on the waveguide with and without containers filled with cell culture medium and with temperature measurements with non-metallic probes in separate heating experiments.

  5. Snake scales, partial exposure, and the Snake Detection Theory: A human event-related potentials study

    NARCIS (Netherlands)

    J.W. van Strien (Jan); L.A. Isbell (Lynne A.)

    2017-01-01

    textabstractStudies of event-related potentials in humans have established larger early posterior negativity (EPN) in response to pictures depicting snakes than to pictures depicting other creatures. Ethological research has recently shown that macaques and wild vervet monkeys respond strongly to

  6. Human responses to carbon dioxide, a follow-up study at recommended exposure limits in non-industrial environments

    DEFF Research Database (Denmark)

    Zhang, Xiaojing; Wargocki, Pawel; Lian, Zhiwei

    2016-01-01

    To extend the results of a previous study on the effects of carbon dioxide (CO2) and bioeffluents on humans, the new study reported in this paper was carried out. The purpose of this study was to examine, whether exposure to CO2 at 5000 ppm would cause sensory discomfort, evoke acute health...... no effect on perceived air quality or physiological responses except for end-tidal CO2 (ETCO2), which increased more (to 5.3 kPa) than it was in the reference condition (5.1 kPa). Other results indicate additionally that a 2.5-h exposure to CO2 up to 5000 ppm did not increase intensity of health symptoms...

  7. Radiation exposure and chromosome abnormalities. Human cytogenetic studies at the National Institute of Radiological Sciences, Japan, 1963-1988

    International Nuclear Information System (INIS)

    Ishihara, T.; Kohno, S.; Minamihisamatsu, M.

    1990-01-01

    The results of human cytogenetic studies performed at the National Institute of Radiological Sciences (NIRS), Chiba, Japan for about 25 years are described. The studies were pursued primarily under two major projects: one involving people exposed to radiation under various conditions and the other involving patients with malignant diseases, especially leukemias. Whereas chromosome abnormalities in radiation-exposed people are excellent indicators of radiation exposure, their behavior in bone marrow provide useful information for a better understanding of chromosome abnormalities in leukemias and related disorders. The role of chromosome abnormalities in the genesis and development of leukemia and related disorders is considered, suggesting a view for future studies in this field

  8. Development of a Biomarker for Penconazole: A Human Oral Dosing Study and a Survey of UK Residents’ Exposure

    Directory of Open Access Journals (Sweden)

    Craig Sams

    2016-05-01

    Full Text Available Penconazole is a widely used fungicide in the UK; however, to date, there have been no peer-reviewed publications reporting human metabolism, excretion or biological monitoring data. The objectives of this study were to i develop a robust analytical method, ii determine biomarker levels in volunteers exposed to penconazole, and, finally, to iii measure the metabolites in samples collected as part of a large investigation of rural residents’ exposure. An LC-MS/MS method was developed for penconazole and two oxidative metabolites. Three volunteers received a single oral dose of 0.03 mg/kg body weight and timed urine samples were collected and analysed. The volunteer study demonstrated that both penconazole-OH and penconazole-COOH are excreted in humans following an oral dose and are viable biomarkers. Excretion is rapid with a half-life of less than four hours. Mean recovery of the administered dose was 47% (range 33%–54% in urine treated with glucuronidase to hydrolyse any conjugates. The results from the residents’ study showed that levels of penconazole-COOH in this population were low with >80% below the limit of detection. Future sampling strategies that include both end of exposure and next day urine samples, as well as contextual data about the route and time of exposure, are recommended.

  9. Study of the uncertainty in estimation of the exposure of non-human biota to ionising radiation.

    Science.gov (United States)

    Avila, R; Beresford, N A; Agüero, A; Broed, R; Brown, J; Iospje, M; Robles, B; Suañez, A

    2004-12-01

    Uncertainty in estimations of the exposure of non-human biota to ionising radiation may arise from a number of sources including values of the model parameters, empirical data, measurement errors and biases in the sampling. The significance of the overall uncertainty of an exposure assessment will depend on how the estimated dose compares with reference doses used for risk characterisation. In this paper, we present the results of a study of the uncertainty in estimation of the exposure of non-human biota using some of the models and parameters recommended in the FASSET methodology. The study was carried out for semi-natural terrestrial, agricultural and marine ecosystems, and for four radionuclides (137Cs, 239Pu, 129I and 237Np). The parameters of the radionuclide transfer models showed the highest sensitivity and contributed the most to the uncertainty in the predictions of doses to biota. The most important ones were related to the bioavailability and mobility of radionuclides in the environment, for example soil-to-plant transfer factors, the bioaccumulation factors for marine biota and the gut uptake fraction for terrestrial mammals. In contrast, the dose conversion coefficients showed low sensitivity and contributed little to the overall uncertainty. Radiobiological effectiveness contributed to the overall uncertainty of the dose estimations for alpha emitters although to a lesser degree than a number of transfer model parameters.

  10. Human health effects of exposure to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Hallenbeck, W.H.

    1986-01-01

    The health effects of human exposure to cadmium are discussed with emphases on intake, absorption, body burden, and excretion; osteomalacia in Japan; hypertension; and proteinuria, emphysema, osteomalacia, and cancer in workers. Elevated blood pressure has not been observed as a result of excessive exposures to cadmium in Japan or the workplace. Renal tubular dysfunction and consequent proteinuria is generally accepted as the main effect following long-term, low-level exposure to cadmium. Studies of workers show that proteinuria may develop after the first year of exposure or many years after the last exposure. Proteinuria and deterioration of renal function may continue even after cessation of exposure. The immediate health significance of low-level proteinuria is still under debate. However, there is evidence that long-term renal tubular dysfunction may lead to abnormalities of calcium metabolism and osteomalacia. The few autopsy and cross-sectional studies of workers do not permit conclusions to be drawn regarding the relationship between cadmium exposure and emphysema. Retrospective and historical-prospective studies are needed to settle this important question. No conclusive evidence has been published regarding cadmium-induced cancer in humans. However, there is sufficient evidence to regard cadmium as a suspect renal and prostate carcinogen. Because of equivocal results and the absence of dose-response relationships, the studies reviewed should be used with caution in making regulatory decisions and low-dose risk assessments. 62 references.

  11. Human health effects of exposure to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Hallenbeck, W.H.

    1984-02-15

    The health effects of human exposure to cadmium are discussed with emphasis on intake, absorption, body burden, and excretion; osteomalacia in Japan; hypertension; and proteinuria, emphysema, osteomalacia, and cancer in workers. Elevated blood pressure has not been observed as a result of excessive exposures to cadmium in Japan or the workplace. Renal tubular dysfunction and consequent proteinuria is generally accepted as the main effect following long-term, low-level exposure to cadmium. Studies of workers show that proteinuria may develop after the first year of exposure or many years after the last exposure. Proteinuria and deterioration of renal function may continue even after cessation of exposure. The immediate health significance of low-level proteinuria is still under debate. However, there is evidence that long-term renal tubular dysfunction may lead to abnormalities of calcium metabolism and osteomalacia. The few autopsy and cross-sectional studies of workers do not permit conclusions to be drawn regarding the relationship between cadmium exposure and emphysema. Retrospective and historical-prospective studies are needed to settle this important question. No conclusive evidence has been published regarding cadmium-induced cancer in humans. However, there is sufficient evidence to regard cadmium as a suspect renal and prostate carcinogen. Because of equivocal results and the absence of dose-response relationships, the studies reviewed should be used with caution in making regulatory decisions and low-dose risk assessments.

  12. The characteristics of atmospheric phthalates in Shanghai: A haze case study and human exposure assessment

    Science.gov (United States)

    Li, Yingjie; Wang, Jiahui; Ren, Bainian; Wang, Hongli; Qiao, Liping; Zhu, Jiping; Li, Li

    2018-04-01

    While phthalates in indoor environments are extensively studied, reports on phthalates in outdoor air, particularly their associations with haze weather events are rare. Phthalates, especially dimethyl phthalate, are known to react with criteria air pollutants contributing to the formation of secondary organic aerosols. This study investigated phthalates levels in the atmosphere in Shanghai with a focus on their associations with different air quality weather events. The air quality during the study period was classified into three levels: non-haze, light pollution and moderate pollution. Phthalates levels were found to be lower in non-haze weather events (236 ng/m3) and higher in moderate pollution weather events (up to 700 ng/m3). Meteorological factors of relative humidity and wind speed had an inverse relationship with phthalates levels. Particulate matter had a positive correlation with phthalates levels. Hydroxyl radical initiated photo-reaction of dimethyl phthalate was evident by its inverse relationship with total atmospheric oxidant (O3 + NO2), indicating that dimethyl phthalate could be one of the precursors of secondary organic aerosol causing haze weather events. Daily intake of phthalates through exposure to outdoor air is estimated to be relatively minor; children intake remains higher on a body weight basis. This is the first study demonstrating the relationship of phthalates and different air quality conditions in haze weather events. The knowledge contributes to our understanding on the cause of haze weather events in China and elsewhere.

  13. A new approach towards biomarker selection in estimation of human exposure to chiral chemicals: a case study of mephedrone.

    Science.gov (United States)

    Castrignanò, Erika; Mardal, Marie; Rydevik, Axel; Miserez, Bram; Ramsey, John; Shine, Trevor; Pantoș, G Dan; Meyer, Markus R; Kasprzyk-Hordern, Barbara

    2017-11-02

    Wastewater-based epidemiology is an innovative approach to estimate public health status using biomarker analysis in wastewater. A new compound detected in wastewater can be a potential biomarker of an emerging trend in public health. However, it is currently difficult to select new biomarkers mainly due to limited human metabolism data. This manuscript presents a new framework, which enables the identification and selection of new biomarkers of human exposure to drugs with scarce or unknown human metabolism data. Mephedrone was targeted to elucidate the assessment of biomarkers for emerging drugs of abuse using a four-step analytical procedure. This framework consists of: (i) identification of possible metabolic biomarkers present in wastewater using an in-vivo study; (ii) verification of chiral signature of the target compound; (iii) confirmation of human metabolic residues in in-vivo/vitro studies and (iv) verification of stability of biomarkers in wastewater. Mephedrone was selected as a suitable biomarker due to its high stability profile in wastewater. Its enantiomeric profiling was studied for the first time in biological and environmental matrices, showing stereoselective metabolism of mephedrone in humans. Further biomarker candidates were also proposed for future investigation: 4'-carboxy-mephedrone, 4'-carboxy-normephedrone, 1-dihydro-mephedrone, 1-dihydro-normephedrone and 4'-hydroxy-normephedrone.

  14. Human Exposure Assessment for Air Pollution.

    Science.gov (United States)

    Han, Bin; Hu, Li-Wen; Bai, Zhipeng

    2017-01-01

    Assessment of human exposure to air pollution is a fundamental part of the more general process of health risk assessment. The measurement methods for exposure assessment now include personal exposure monitoring, indoor-outdoor sampling, mobile monitoring, and exposure assessment modeling (such as proximity models, interpolation model, air dispersion models, and land-use regression (LUR) models). Among these methods, personal exposure measurement is considered to be the most accurate method of pollutant exposure assessment until now, since it can better quantify observed differences and better reflect exposure among smaller groups of people at ground level. And since the great differences of geographical environment, source distribution, pollution characteristics, economic conditions, and living habits, there is a wide range of differences between indoor, outdoor, and individual air pollution exposure in different regions of China. In general, the indoor particles in most Chinese families comprise infiltrated outdoor particles, particles generated indoors, and a few secondary organic aerosol particles, and in most cases, outdoor particle pollution concentrations are a major contributor to indoor concentrations in China. Furthermore, since the time, energy, and expense are limited, it is difficult to measure the concentration of pollutants for each individual. In recent years, obtaining the concentration of air pollutants by using a variety of exposure assessment models is becoming a main method which could solve the problem of the increasing number of individuals in epidemiology studies.

  15. Human biological monitoring of occupational genotoxic exposures

    DEFF Research Database (Denmark)

    Knudsen, Lisbeth E.; Sorsa, M

    1993-01-01

    Human biological monitoring is a valuable tool for exposure assessment in groups of persons occupationally exposed to genotoxic agents. If the monitoring activity covers genetic material the term genetic monitoring is used. The methods used for genetic monitoring are either substance specific, e......) occupational exposure limit value of styrene in ambient air. The consideration of ethical issues in human genetic monitoring is an important but often overlooked aspect. This includes the scientific and preventional relevance of performing a test on individuals, pre- and post study information of donors...

  16. Carcinogen derived biomarkers: applications in studies of human exposure to secondhand tobacco smoke

    OpenAIRE

    Hecht, S

    2004-01-01

    Objective: To review the literature on carcinogen derived biomarkers of exposure to secondhand tobacco smoke (SHS). These biomarkers are specifically related to known carcinogens in tobacco smoke and include urinary metabolites, DNA adducts, and blood protein adducts.

  17. Study on indoor radon exposure and its effect on human health

    International Nuclear Information System (INIS)

    Lu Xinwei

    2005-01-01

    Radon and its daughters relate to people health. Radon widely exists in the nature. The paper discusses the source, exposure and activity level of indoor radon, systematically analyzes the hazards and dose-response of residential radon exposure, and at last indicates the concrete method of controlling residential radon concentration. By interdicting radon pollution source and ventilation might effectively reduce indoor radon concentration and improve environmental air quality. (authors)

  18. Snake scales, partial exposure, and the Snake Detection Theory: A human event-related potentials study

    Science.gov (United States)

    Van Strien, Jan W.; Isbell, Lynne A.

    2017-01-01

    Studies of event-related potentials in humans have established larger early posterior negativity (EPN) in response to pictures depicting snakes than to pictures depicting other creatures. Ethological research has recently shown that macaques and wild vervet monkeys respond strongly to partially exposed snake models and scale patterns on the snake skin. Here, we examined whether snake skin patterns and partially exposed snakes elicit a larger EPN in humans. In Task 1, we employed pictures with close-ups of snake skins, lizard skins, and bird plumage. In task 2, we employed pictures of partially exposed snakes, lizards, and birds. Participants watched a random rapid serial visual presentation of these pictures. The EPN was scored as the mean activity (225–300 ms after picture onset) at occipital and parieto-occipital electrodes. Consistent with previous studies, and with the Snake Detection Theory, the EPN was significantly larger for snake skin pictures than for lizard skin and bird plumage pictures, and for lizard skin pictures than for bird plumage pictures. Likewise, the EPN was larger for partially exposed snakes than for partially exposed lizards and birds. The results suggest that the EPN snake effect is partly driven by snake skin scale patterns which are otherwise rare in nature. PMID:28387376

  19. Increase in oxidative stress levels following welding fume inhalation: a controlled human exposure study.

    Science.gov (United States)

    Graczyk, Halshka; Lewinski, Nastassja; Zhao, Jiayuan; Sauvain, Jean-Jacques; Suarez, Guillaume; Wild, Pascal; Danuser, Brigitta; Riediker, Michael

    2016-06-10

    Tungsten inert gas (TIG) welding represents one of the most widely used metal joining processes in industry. It has been shown to generate a large majority of particles at the nanoscale and to have low mass emission rates when compared to other types of welding. Despite evidence that TIG fume particles may produce reactive oxygen species (ROS), limited data is available for the time course changes of particle-associated oxidative stress in exposed TIG welders. Twenty non-smoking male welding apprentices were exposed to TIG welding fumes for 60 min under controlled, well-ventilated settings. Exhaled breathe condensate (EBC), blood and urine were collected before exposure, immediately after exposure, 1 h and 3 h post exposure. Volunteers participated in a control day to account for oxidative stress fluctuations due to circadian rhythm. Biological liquids were assessed for total reducing capacity, hydrogen peroxide (H2O2), malondialdehyde (MDA), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentrations at each time point. A linear mixed model was used to assess within day and between day differences. Significant increases in the measured biomarkers were found at 3 h post exposure. At 3 h post exposure, we found a 24 % increase in plasma-H2O2 concentrations ([95%CI: 4 % to 46 %], p = 0.01); a 91 % increase in urinary-H2O2 ([2 % to 258 %], p = 0.04); a 14 % increase in plasma-8-OHdG ([0 % to 31 %], p = 0.049); and a 45 % increase in urinary-8-OHdG ([3 % to 105 %], p = 0.03). Doubling particle number concentration (PNC) exposure was associated with a 22 % increase of plasma-8-OHdG at 3 h post exposure (p = 0.01). A 60-min exposure to TIG welding fume in a controlled, well-ventilated setting induced acute oxidative stress at 3 h post exposure in healthy, non-smoking apprentice welders not chronically exposed to welding fumes. As mass concentration of TIG welding fume particles is very low when compared to other types of welding, it is

  20. Human health and exposure to electromagnetic radiation

    International Nuclear Information System (INIS)

    Dennis, J.A.; Muirhead, C.R.; Ennis, J.R.

    1992-07-01

    This review consists of three main parts. In the first the general features of electromagnetic fields and their interactions with the human body are described. The second part deals with the epidemiological evidence for effects on general health and birth outcome. The third part describes the epidemiological evidence from occupational and residential studies of a possible association between electromagnetic field exposures and cancer. (author)

  1. Post exposure prophylaxis against human immunodeficiency virus ...

    African Journals Online (AJOL)

    Objective: To determine the level of awareness, knowledge and practice of human immunodeficiency virus post exposure prophylaxis (HIV PEP) among paediatricians in Nigeria. Methodology: The study was a cross sectional questionnairebased survey conducted among paediatrcians that attended the Paediatric ...

  2. Sampling strategy for estimating human exposure pathways to consumer chemicals

    NARCIS (Netherlands)

    Papadopoulou, Eleni; Padilla-Sanchez, Juan A.; Collins, Chris D.; Cousins, Ian T.; Covaci, Adrian; de Wit, Cynthia A.; Leonards, Pim E.G.; Voorspoels, Stefan; Thomsen, Cathrine; Harrad, Stuart; Haug, Line S.

    2016-01-01

    Human exposure to consumer chemicals has become a worldwide concern. In this work, a comprehensive sampling strategy is presented, to our knowledge being the first to study all relevant exposure pathways in a single cohort using multiple methods for assessment of exposure from each exposure pathway.

  3. Study of Physiological Responses to Acute Carbon Monoxide Exposure with a Human Patient Simulator

    Science.gov (United States)

    Cesari, Whitney A.; Caruso, Dominique M.; Zyka, Enela L.; Schroff, Stuart T.; Evans, Charles H., Jr.; Hyatt, Jon-Philippe K.

    2006-01-01

    Human patient simulators are widely used to train health professionals and students in a clinical setting, but they also can be used to enhance physiology education in a laboratory setting. Our course incorporates the human patient simulator for experiential learning in which undergraduate university juniors and seniors are instructed to design,…

  4. Human mutagens: evidence from paternal exposure

    International Nuclear Information System (INIS)

    Narod, S.A.; Douglas, G.R.; Nestmann, E.R.; Blakey, D.H.

    1988-01-01

    The importance of inherited mutations as a cause of human disease has been established clearly through examples of well-defined genetic anomalies, such as Down syndrome and retinoblastoma. Furthermore, it is suspected that environmental contaminants induce mutations resulting in increased risk for such defects in subsequent generations of persons exposed. The present lack of direct evidence for induced inherited genetic disorders in human beings hampers the development of risk estimation techniques for extrapolation from animal models. The most extensive prospective epidemiologic studies of inherited genetic effects have involved survivors of atomic bomb detonations and patients treated with cancer chemotherapy. In neither case has a significant elevation in inherited genetic effects or cancer been detected in the offspring of exposed individuals. Epidemiologic studies of subjects receiving chronic exposure may be confounded by the effect of maternal exposure during pregnancy. Consideration of only paternal exposure can minimize the confounding influence of teratogenicity, enhancing the resolving power of studies for inherited effects. Using this approach, retrospective (case-control) studies of childhood cancer patients have provided limited but suggestive evidence for inheritance of induced effects. Endpoints, such as congenital malformations and spontaneous abortion following paternal exposure, can also be considered as indicators of heritable mutagenic effects. For example, there is limited evidence suggesting that paternal exposure to anaesthetic gases may cause miscarriage and congenital abnormalities as a result of induced male germ cell mutations. 104 references

  5. A translatable predictor of human radiation exposure.

    Science.gov (United States)

    Lucas, Joseph; Dressman, Holly K; Suchindran, Sunil; Nakamura, Mai; Chao, Nelson J; Himburg, Heather; Minor, Kerry; Phillips, Gary; Ross, Joel; Abedi, Majid; Terbrueggen, Robert; Chute, John P

    2014-01-01

    Terrorism using radiological dirty bombs or improvised nuclear devices is recognized as a major threat to both public health and national security. In the event of a radiological or nuclear disaster, rapid and accurate biodosimetry of thousands of potentially affected individuals will be essential for effective medical management to occur. Currently, health care providers lack an accurate, high-throughput biodosimetric assay which is suitable for the triage of large numbers of radiation injury victims. Here, we describe the development of a biodosimetric assay based on the analysis of irradiated mice, ex vivo-irradiated human peripheral blood (PB) and humans treated with total body irradiation (TBI). Interestingly, a gene expression profile developed via analysis of murine PB radiation response alone was inaccurate in predicting human radiation injury. In contrast, generation of a gene expression profile which incorporated data from ex vivo irradiated human PB and human TBI patients yielded an 18-gene radiation classifier which was highly accurate at predicting human radiation status and discriminating medically relevant radiation dose levels in human samples. Although the patient population was relatively small, the accuracy of this classifier in discriminating radiation dose levels in human TBI patients was not substantially confounded by gender, diagnosis or prior exposure to chemotherapy. We have further incorporated genes from this human radiation signature into a rapid and high-throughput chemical ligation-dependent probe amplification assay (CLPA) which was able to discriminate radiation dose levels in a pilot study of ex vivo irradiated human blood and samples from human TBI patients. Our results illustrate the potential for translation of a human genetic signature for the diagnosis of human radiation exposure and suggest the basis for further testing of CLPA as a candidate biodosimetric assay.

  6. A translatable predictor of human radiation exposure.

    Directory of Open Access Journals (Sweden)

    Joseph Lucas

    Full Text Available Terrorism using radiological dirty bombs or improvised nuclear devices is recognized as a major threat to both public health and national security. In the event of a radiological or nuclear disaster, rapid and accurate biodosimetry of thousands of potentially affected individuals will be essential for effective medical management to occur. Currently, health care providers lack an accurate, high-throughput biodosimetric assay which is suitable for the triage of large numbers of radiation injury victims. Here, we describe the development of a biodosimetric assay based on the analysis of irradiated mice, ex vivo-irradiated human peripheral blood (PB and humans treated with total body irradiation (TBI. Interestingly, a gene expression profile developed via analysis of murine PB radiation response alone was inaccurate in predicting human radiation injury. In contrast, generation of a gene expression profile which incorporated data from ex vivo irradiated human PB and human TBI patients yielded an 18-gene radiation classifier which was highly accurate at predicting human radiation status and discriminating medically relevant radiation dose levels in human samples. Although the patient population was relatively small, the accuracy of this classifier in discriminating radiation dose levels in human TBI patients was not substantially confounded by gender, diagnosis or prior exposure to chemotherapy. We have further incorporated genes from this human radiation signature into a rapid and high-throughput chemical ligation-dependent probe amplification assay (CLPA which was able to discriminate radiation dose levels in a pilot study of ex vivo irradiated human blood and samples from human TBI patients. Our results illustrate the potential for translation of a human genetic signature for the diagnosis of human radiation exposure and suggest the basis for further testing of CLPA as a candidate biodosimetric assay.

  7. Study of spatiotemporal variation of atmospheric mercury and its human exposure around an integrated steel plant, India

    Science.gov (United States)

    Pervez, S.; Koshle, A.; Pervez, Y.

    2010-06-01

    Mercury release by coal combustion has been significantly increased in India. Mercury content in coal has been analyzed to 0.272 ppm by Central Pollution Control Board. Toxicological effects of elemental Hg (Hg0) exposure include respiratory and renal failures, cardiac arrest, and cerebral oedema, while subclinical exposure may induce kidney, behavioral, and cognitive dysfunctions. The present work is focused on dispersion pattern and inter-phase exchange phenomena of ambient mercury between air-particulate matter evaluations of alongwith dominance of various major routes of human exposure-dose response using regression analysis around an integrated steel plant in central India. Source-downwind type stratified random sampling plan using longitudinal study design has been adopted for ambient monitoring of total mercury, while representative sampling plant has been adopted for persona exposure-dose response study In space-time framework. Control sites and subjects have been chosen from uncontaminated area (100 km away from any industrial activities). 06 ambient air monitoring stations and 17 subjects from workers, non-workers but local residents' categories and from controlled sites have been chosen for the study. Samples of mercury biomarkers (blood, breast milk and urine) have also been collected from same subjects in each month during sampling period. The sampling period was March 2005 to February 2006 . Samples of 30% acidified KMnO4 for air-Hg absorption, PM10, RPM and biological samples were analyzed for total mercury by ICP-AES using standard methods. Local soils and ground water were also monitored for total mercury content during the sampling period. Results have shown that mercury concentration is very high compared to prescribed limits in all receptors. Results of exchange phenomenon have shown the higher transfer of mercury from air to particulate during combustion in steel plant environment due to presence of huge amount of iron particles, in contrast to

  8. Associations Between Exposure to and Expression of Negative Opinions About Human Papillomavirus Vaccines on Social Media: An Observational Study.

    Science.gov (United States)

    Dunn, Adam G; Leask, Julie; Zhou, Xujuan; Mandl, Kenneth D; Coiera, Enrico

    2015-06-10

    Groups and individuals that seek to negatively influence public opinion about the safety and value of vaccination are active in online and social media and may influence decision making within some communities. We sought to measure whether exposure to negative opinions about human papillomavirus (HPV) vaccines in Twitter communities is associated with the subsequent expression of negative opinions by explicitly measuring potential information exposure over the social structure of Twitter communities. We hypothesized that prior exposure to opinions rejecting the safety or value of HPV vaccines would be associated with an increased risk of posting similar opinions and tested this hypothesis by analyzing temporal sequences of messages posted on Twitter (tweets). The study design was a retrospective analysis of tweets related to HPV vaccines and the social connections between users. Between October 2013 and April 2014, we collected 83,551 English-language tweets that included terms related to HPV vaccines and the 957,865 social connections among 30,621 users posting or reposting the tweets. Tweets were classified as expressing negative or neutral/positive opinions using a machine learning classifier previously trained on a manually labeled sample. During the 6-month period, 25.13% (20,994/83,551) of tweets were classified as negative; among the 30,621 users that tweeted about HPV vaccines, 9046 (29.54%) were exposed to a majority of negative tweets. The likelihood of a user posting a negative tweet after exposure to a majority of negative opinions was 37.78% (2780/7361) compared to 10.92% (1234/11,296) for users who were exposed to a majority of positive and neutral tweets corresponding to a relative risk of 3.46 (95% CI 3.25-3.67, Prelation to HPV vaccines. We found that among users that tweeted about HPV vaccines, those who were more often exposed to negative opinions were more likely to subsequently post negative opinions. Although this research may be useful for

  9. ASSESSMENT OF HUMAN EXPOSURE TO TOLUENE DIISOCYANATE

    Directory of Open Access Journals (Sweden)

    OLIVIA ANCA RUSU

    2011-03-01

    Full Text Available Assessment of human exposure to toluene diisocyanate. Toluene diisocyanate (TDI, an aromatic compound, may be dangerous for human health. Diisocyanates have wide industrial use in the fabrication of flexible and rigid foams, fibers, elastomers, and coatings such as paints and varnishes. Isocyanates are known skin and respiratory sensitizers, and proper engineering controls should be in place to prevent exposure to isocyanate liquid and vapor; exposure to TDI vapors is well documented to increase asthma risk. The study focused on the exposure of workers and nearby populations to toluene diisocyanate in a Polyurethane Foam Factory located in Baia Mare, Romania. Workplace air measurements were performed in different departments of the plant, after sampling either in fixed points or as personal monitoring. Sampling in four different locations of Baia Mare town was carried out, - during and after the foaming process. TDI sampling was performed on silica cartridge followed by GC-MS analysis. TDI concentration at workplace was lower than 0,035 mg/m³, which represents the permissible exposure limit, while in the city the TDI concentration had shown values below 0,20 μg/m³. Health assessment of a group of 49 workers was based on questionnaire interview, determination of TDI antibodies and lung function tests. Data collected until this stage do not show any negative effects of TDI on the employees health. Since this plant had only recently begun operating, continuous workplace and ambient air TDI monitoring, along with workers health surveillance, is deemed necessary.

  10. Exposure to Hedione Increases Reciprocity in Humans

    Directory of Open Access Journals (Sweden)

    Sebastian Berger

    2017-05-01

    Full Text Available Cooperation among unrelated humans is frequently regarded as a defining feature in the evolutionary success of our species. Whereas, much research has addressed the strategic and cognitive mechanisms that underlie cooperation, investigations into chemosensory processes have received very limited research attention. To bridge that gap, we build on recent research that has identified the chemically synthesized odorant Hedione (HED as a ligand for the putative human pheromone receptor (VN1R1 expressed in the olfactory mucosa, and hypothesize that exposure to HED may increase reciprocity. Applying behavioral economics paradigms, the present research shows that exposure to the ligand causes differentiated behavioral effects in reciprocal punishments (Study 1 as well as rewards (Study 2, two types of behaviors that are frequently regarded as essential for the development and maintenance of cooperation.

  11. Exposure to Hedione Increases Reciprocity in Humans

    Science.gov (United States)

    Berger, Sebastian; Hatt, Hanns; Ockenfels, Axel

    2017-01-01

    Cooperation among unrelated humans is frequently regarded as a defining feature in the evolutionary success of our species. Whereas, much research has addressed the strategic and cognitive mechanisms that underlie cooperation, investigations into chemosensory processes have received very limited research attention. To bridge that gap, we build on recent research that has identified the chemically synthesized odorant Hedione (HED) as a ligand for the putative human pheromone receptor (VN1R1) expressed in the olfactory mucosa, and hypothesize that exposure to HED may increase reciprocity. Applying behavioral economics paradigms, the present research shows that exposure to the ligand causes differentiated behavioral effects in reciprocal punishments (Study 1) as well as rewards (Study 2), two types of behaviors that are frequently regarded as essential for the development and maintenance of cooperation. PMID:28512400

  12. Identification of fipronil metabolites in rodents by time-of-flight mass spectrometry for application in a human exposure study

    Science.gov (United States)

    Fipronil is a phenylpyrazole insecticide commonly used in residential and agricultural applications. To understand more about the potential risks associated with fipronil, dosed Long Evans rats were evaluated for metabolites to develop a set of biomarkers for use in human exposur...

  13. Effects of artificial light at night on human health: A literature review of observational and experimental studies applied to exposure assessment.

    Science.gov (United States)

    Cho, YongMin; Ryu, Seung-Hun; Lee, Byeo Ri; Kim, Kyung Hee; Lee, Eunil; Choi, Jaewook

    2015-01-01

    It has frequently been reported that exposure to artificial light at night (ALAN) may cause negative health effects, such as breast cancer, circadian phase disruption and sleep disorders. Here, we reviewed the literature assessing the effects of human exposure to ALAN in order to list the health effects of various aspects of ALAN. Several electronic databases were searched for articles, published through August 2014, related to assessing the effects of exposure to ALAN on human health; these also included the details of experiments on such exposure. A total of 85 articles were included in the review. Several observational studies showed that outdoor ALAN levels are a risk factor for breast cancer and reported that indoor light intensity and individual lighting habits were relevant to this risk. Exposure to artificial bright light during the nighttime suppresses melatonin secretion, increases sleep onset latency (SOL) and increases alertness. Circadian misalignment caused by chronic ALAN exposure may have negative effects on the psychological, cardiovascular and/or metabolic functions. ALAN also causes circadian phase disruption, which increases with longer duration of exposure and with exposure later in the evening. It has also been reported that shorter wavelengths of light preferentially disturb melatonin secretion and cause circadian phase shifts, even if the light is not bright. This literature review may be helpful to understand the health effects of ALAN exposure and suggests that it is necessary to consider various characteristics of artificial light, beyond mere intensity.

  14. Human exposure to thallium through tap water: A study from Valdicastello Carducci and Pietrasanta (northern Tuscany, Italy).

    Science.gov (United States)

    Campanella, Beatrice; Onor, Massimo; D'Ulivo, Alessandro; Giannecchini, Roberto; D'Orazio, Massimo; Petrini, Riccardo; Bramanti, Emilia

    2016-04-01

    A geological study evidenced the presence of thallium (Tl) at concentrations of concern in groundwaters near Valdicastello Carducci (Tuscany, Italy). The source of contamination has been identified in the Tl-bearing pyrite ores occurring in the abandoned mining sites of the area. The strongly acidic internal waters flowing in the mining tunnels can reach exceptional Tl concentrations, up to 9000μg/L. In September 2014 Tl contamination was also found in the tap water distributed in the same area (from 2 to 10μg/L). On October 3, 2014 the local authorities imposed a Do Not Drink order to the population. Here we report the results of the exposure study carried out from October 2014 to October 2015, and aimed at quantifying Tl levels in 150 urine and 318 hair samples from the population of Valdicastello Carducci and Pietrasanta. Thallium was quantified by inductively coupled plasma - mass spectrometry (ICP-MS). Urine and hair were chosen as model matrices indicative of different time periods of exposure (short-term and long-term, respectively). Thallium values found in biological samples were correlated with Tl concentrations found in tap water in the living area of each citizen, and with his/her habits. Thallium concentration range found in hair and urine was 1-498ng/g (values in unexposed subjects 0.1-6ng/g) and 0.046-5.44μg/L (reference value for the European population 0.006μg/L), respectively. Results show that Tl levels in biological samples were significantly associated with residency in zones containing elevated water Tl levels. The kinetics of decay of Tl concentration in urine samples was also investigated. At the best of our knowledge, this is the first study on human contamination by Tl through water involving such a high number of samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Common studied polymorphisms do not affect plasma cytokine levels upon endotoxin exposure in humans

    DEFF Research Database (Denmark)

    Taudorf, Sarah; Krabbe, K.S.; Berg, R.M.

    2008-01-01

    The aim of this study was to investigate to what extent single nucleotide polymorphisms (SNPs) in promoter regions of genes of Toll-like receptor (TLR)-4, tumour necrosis factor (TNF)-alpha, interleukin (IL)-18, interferon (IFN)-gamma, IL-6 and IL-10 affect the cytokine response during a controlled......-607, IFN-gamma+874, IL-6-174, IL-10-592 and IL-10-1082) and endotoxin-induced changes in plasma levels of TNF-alpha, IL-6 and IL-10. IL-18 levels were unaffected by endotoxin. In conclusion, the investigated SNPs did not affect endotoxin-induced low-grade cytokine production of TNF-alpha, IL-6, IL-18 or IL......-10 in healthy young men. Previous reports of a major heritability factor in the inflammatory response may be due to other target genes or effects in older age groups or women Udgivelsesdato: 2008/4...

  16. Human exposure to power frequency magnetic fields up to 7.6 mT: An integrated EEG/fMRI study.

    Science.gov (United States)

    Modolo, Julien; Thomas, Alex W; Legros, Alexandre

    2017-09-01

    We assessed the effects of power-line frequency (60 Hz in North America) magnetic fields (MF) in humans using simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). Twenty-five participants were enrolled in a pseudo-double-blind experiment involving "real" or "sham" exposure to sinusoidal 60 Hz MF exposures delivered using the gradient coil of an MRI scanner following two conditions: (i) 10 s exposures at 3 mT (10 repetitions); (ii) 2 s exposures at 7.6 mT (100 repetitions). Occipital EEG spectral power was computed in the alpha range (8-12 Hz, reportedly the most sensitive to MF exposure in the literature) with/without exposure. Brain functional activation was studied using fMRI blood oxygen level-dependent (BOLD, inversely correlated with EEG alpha power) maps. No significant effects were detected on occipital EEG alpha power during or post-exposure for any exposure condition. Consistent with EEG results, no effects were observed on fMRI BOLD maps in any brain region. Our results suggest that acute exposure (2-10 s) to 60 Hz MF from 3 to 7.6 mT (30,000 to 76,000 times higher than average public exposure levels for 60 Hz MF) does not induce detectable changes in EEG or BOLD signals. Combined with previous findings in which effects were observed on the BOLD signal after 1 h exposure to 3 mT, 60 Hz MF, this suggests that MF exposure in the low mT range (<10 mT) might require prolonged durations of exposure to induce detectable effects. Bioelectromagnetics. 38:425-435, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  17. Human exposure assessment to environmental chemicals using biomonitoring.

    Science.gov (United States)

    Calafat, Antonia M; Ye, Xiaoyun; Silva, Manori J; Kuklenyik, Zsuzsanna; Needham, Larry L

    2006-02-01

    In modern societies, humans may be exposed to a wide spectrum of environmental chemicals. Although the health significance of this exposure for many chemicals is unknown, studies to investigate the prevalence of exposure are warranted because of the chemicals' potential harmful health effects, as often indicated in animal studies. Three tools have been used to assess exposure: exposure history/questionnaire information, environmental monitoring, and biomonitoring (i.e. measuring concentrations of the chemicals, their metabolites, or their adducts in human specimens). We present an overview on the use of biomonitoring in exposure assessment using phthalates, bisphenol A and other environmental phenols, and perfluorinated chemicals as examples. We discuss some factors relevant for interpreting and understanding biomonitoring data, including selection of both biomarkers of exposure and human matrices, and toxicokinetic information. The use of biomonitoring in human risk assessment is not discussed.

  18. Human response to combined indoor environment exposures

    DEFF Research Database (Denmark)

    Toftum, Jørn

    2002-01-01

    Most thermal comfort standards and guidelines presume sedentary, light activity and a neutral overall thermal sensation when predicting local thermal discomfort. In addition, current standards specify criteria for separate aspects of the indoor environment, e.g. thermal climate, air quality...... or noise, with only little consideration of possible interactions between the different types of exposure. The studies summarized in this article found a clear impact of activity and overall thermal sensation on human sensitivity to air movement, whereas no interaction effects of exposure to several local...... thermal discomfort factors were observed. Limited evidence was found of significant interactions between different aspects of the indoor environment. Only for the effect of air temperature and air humidity on sensory air quality were well-estabished relationships available....

  19. Exposure to UV radiation and human health

    Science.gov (United States)

    Kimlin, Michael G.

    2005-08-01

    This paper will overview the significant issues facing researchers in relating the impact of exposure to sunlight and human health. Exposure to solar ultraviolet radiation is the major causative factor in most sun-related skin and eye disorders, however, very little is known quantitatively about human UV exposures. Interestingly, human exposure to sunlight also has a nutritional impact, namely the development of pre-Vitamin D, which is an important nutrient in bone health. New research suggest that low vitamin D status may be a causative factor in the development of selective types of cancer and autoimminue diseases, as well as a contributing factor in bone health. The 'health duality' aspect of sunlight exposure is an interesting and controversial topic that is a research focus of Kimlin's research group.

  20. Acrylonitrile exposure assessment in the emergency responders of a major train accident in Belgium: a human biomonitoring study.

    Science.gov (United States)

    Van Nieuwenhuyse, A; Fierens, S; De Smedt, T; De Cremer, K; Vleminckx, C; Mertens, B; Van Overmeire, I; Bader, M; De Paepe, P; Göen, T; Nemery, B; Schettgen, T; Stove, C; Van Oyen, H; Van Loco, J

    2014-12-15

    On May 4, 2013, a train transporting chemicals derailed in Wetteren, Belgium. Several tanks loaded with acrylonitrile (ACN) exploded, resulting in a fire and a leakage of ACN. To determine exposure to ACN and to assess discriminating factors for ACN exposure in the emergency responders involved in the on-site management of the train accident. The study population consisted of 841 emergency responders. Between May 21 and June 28, they gave blood for the determination of N-2-cyanoethylvaline (CEV) hemoglobin adducts and urine for the measurement of cotinine. They also filled in a short questionnaire. 163 (26%) non-smokers and 55 (27%) smokers showed CEV concentrations above the reference values of 10 and 200 pmol/g globin, respectively. The 95th percentile in the non-smokers was 73 pmol/g globin and the maximum was 452 pmol/g globin. ACN exposure among the non-smokers was predicted by (1) the distance to the accident, (2) the duration of exposure, and (3) the occupational function. Emergency responders involved in the on-site management of the train accident were clearly exposed to ACN from the accident. However, the extent of exposure remained relatively moderate with CEV concentrations staying within the ranges described in literature as background for a smoking population. Moreover, the exposure was less pronounced in the emergency responders as compared to that in the local population. Copyright © 2014. Published by Elsevier Ireland Ltd.

  1. Linking Meteorology, Air Quality Models and Observations to Characterize Human Exposures in Support of the Environmental Health Studies

    Science.gov (United States)

    Epidemiologic studies are critical in establishing the association between exposure to air pollutants and adverse health effects. Results of epidemiologic studies are used by U.S. EPA in developing air quality standards to protect the public from the health effects of air polluta...

  2. Challenging conventional risk assessment with respect to human exposure to multiple food contaminants in food: A case study using maize.

    Science.gov (United States)

    Clarke, R; Connolly, L; Frizzell, C; Elliott, C T

    2015-10-01

    Mycotoxins and heavy metals are ubiquitous in the environment and contaminate many foods. The widespread use of pesticides in crop production to control disease contributes further to the chemical contamination of foods. Thus multiple chemical contaminants threaten the safety of many food commodities; hence the present study used maize as a model crop to identify the severity in terms of human exposure when multiple contaminants are present. High Content Analysis (HCA) measuring multiple endpoints was used to determine cytotoxicity of complex mixtures of mycotoxins, heavy metals and pesticides. Endpoints included nuclear intensity (NI), nuclear area (NA), plasma membrane permeability (PMP), mitochondrial membrane potential (MMP) and mitochondrial mass (MM). At concentrations representing legal limits of each individual contaminant in maize (3ng/ml ochratoxin A (OTA), 1μg/ml fumonisin B1 (FB1), 2ng/ml aflatoxin B1 (AFB1), 100ng/ml cadmium (Cd), 150ng/ml arsenic (As), 50ng/ml chlorpyrifos (CP) and 5μg/ml pirimiphos methyl (PM), the mixtures (tertiary mycotoxins plus Cd/As) and (tertiary mycotoxins plus Cd/As/CP/PM) were cytotoxic for NA and MM endpoints with a difference of up to 13.6% (p≤0.0001) and 12% (p≤0.0001) respectively from control values. The most cytotoxic mixture was (tertiary mycotoxins plus Cd/As/CP/PM) across all 4 endpoints (NA, NI, MM and MMP) with increases up to 61.3%, 23.0%, 61.4% and 36.3% (p≤0.0001) respectively. Synergy was evident for two endpoints (NI and MM) at concentrations contaminating maize above legal limits, with differences between expected and measured values of (6.2-12.4% (p≤0.05-p≤0.001) and 4.5-12.3% (p≤0.05-p≤0.001) for NI and MM, respectively. The study introduces for the first time, a holistic approach to identify the impact in terms of toxicity to humans when multiple chemical contaminants are present in foodstuffs. Governmental regulatory bodies must begin to contemplate how to safeguard the population when

  3. Assessment of human hair as an indicator of exposure to organophosphate flame retardants. Case study on a Norwegian mother-child cohort.

    Science.gov (United States)

    Kucharska, Agnieszka; Cequier, Enrique; Thomsen, Cathrine; Becher, Georg; Covaci, Adrian; Voorspoels, Stefan

    2015-10-01

    A major challenge of non-invasive human biomonitoring using hair is to assess whether it can be used as an indicator of exposure to Flame Retardants, such as Organophosphate Flame Retardants (PFRs), since the contribution of atmospheric deposition (air and/or dust) cannot be neglected. Therefore, the aim of this study was to evaluate the suitability of using human hair more thoroughly by comparison of (i) levels of PFRs in human hair (from 48 mothers and 54 children), with levels measured in dust and air in their respective households; and (ii) levels of selected PFRs in hair with the levels of corresponding PFR metabolites in matching urine samples collected simultaneously. Most PFRs (tri-n-butyl phosphate (TNBP), 2-ethyl-hexyldiphenyl phosphate (EHDPHP), tri-phenyl phosphate (TPHP), tri-iso-butyl phosphate (TIBP), and tris(2-butoxyethyl) phosphate (TBOEP)) were detected in all human hair samples, tris(2-ethylhexyl) phosphate (TEHP) and tris(1,3-dichloro-iso-propyl) phosphate (TDCIPP) in 93%, tri-cresyl-phosphate (TCP) in 69% and tris(2-chloroethyl) phosphate (TCEP) in 21% of the samples. Levels of individual PFRs ranged between human hair and PFR levels in house dust and/or air were found, e.g. Spearman correlation (rS = 0.561, p exposure. To the best of our knowledge, this is the first study with such design and our findings might help to understand human exposure to and body burdens of PFRs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Institutional review board challenges related to community-based participatory research on human exposure to environmental toxins: A case study

    Directory of Open Access Journals (Sweden)

    Rudel Ruthann A

    2010-07-01

    Full Text Available Abstract Background We report on the challenges of obtaining Institutional Review Board (IRB coverage for a community-based participatory research (CBPR environmental justice project, which involved reporting biomonitoring and household exposure results to participants, and included lay participation in research. Methods We draw on our experiences guiding a multi-partner CBPR project through university and state Institutional Review Board reviews, and other CBPR colleagues' written accounts and conference presentations and discussions. We also interviewed academics involved in CBPR to learn of their challenges with Institutional Review Boards. Results We found that Institutional Review Boards are generally unfamiliar with CBPR, reluctant to oversee community partners, and resistant to ongoing researcher-participant interaction. Institutional Review Boards sometimes unintentionally violate the very principles of beneficence and justice which they are supposed to uphold. For example, some Institutional Review Boards refuse to allow report-back of individual data to participants, which contradicts the CBPR principles that guide a growing number of projects. This causes significant delays and may divert research and dissemination efforts. Our extensive education of our university Institutional Review Board convinced them to provide human subjects protection coverage for two community-based organizations in our partnership. Conclusions IRBs and funders should develop clear, routine review guidelines that respect the unique qualities of CBPR, while researchers and community partners can educate IRB staff and board members about the objectives, ethical frameworks, and research methods of CBPR. These strategies can better protect research participants from the harm of unnecessary delays and exclusion from the research process, while facilitating the ethical communication of study results to participants and communities.

  5. Exposure to power-frequency magnetic fields and the risk of infertility and adverse pregnancy outcomes: update on the human evidence and recommendations for future study designs

    Science.gov (United States)

    Lewis, Ryan C.; Hauser, Russ; Maynard, Andrew D.; Neitzel, Richard L.; Wang, Lu; Kavet, Robert; Meeker, John D.

    2016-01-01

    Infertility and adverse pregnancy outcomes are significant public health concerns with global prevalence. Over the past 35 years, research has addressed whether exposure to power-frequency magnetic fields is one of the etiologic factors attributed to these conditions. However, no apparent authoritative reviews on this topic have been published in the peer-reviewed literature for nearly 15 years. This review provides an overview and critical analysis of human studies that were published in the peer-reviewed literature between 2002 and July 2015. Using PubMed, 13 epidemiology studies published during this timeframe that concern exposure to magnetic fields and adverse prenatal (e.g., miscarriage), neonatal (e.g., preterm birth or birth defects), and male fertility (e.g., poor semen quality) outcomes were identified. Some of these studies reported associations whereas others did not, and study design limitations may explain these inconsistencies. Future investigations need to be designed with these limitations in mind to address existing research gaps. In particular, the following issues are discussed: 1) importance of selecting the appropriate study population, 2) need for addressing confounding due to unmeasured physical activity, 3) importance of minimizing information bias from exposure measurement error, 4) consideration of alternative magnetic field exposure metrics, and 5) implications and applications of personal exposure data that is correlated within female-male couples. Further epidemiologic research is needed given the near ubiquitous exposures to power-frequency magnetic fields in the general population. PMID:27030583

  6. Human exposure to dioxin from combustion sources

    International Nuclear Information System (INIS)

    Hattemer-Frey, H.A.; Travis, C.C.

    1988-01-01

    Because of their extreme toxicity, much concern and debate has arisen about the nature and extent of human exposure to dioxin. Since municipal solid waste (MSW) incinerators are known to emit polychorinated dibenzo-p-dioxins (PCDDs) and polycholorinated dibenzofurnas (PCDFs) many people who live near MSW incinerators fear that they will be exposed to high levels of dioxin and subsequently develop cancer. What is often overlooked in this debate, however, is the fact that the general population is continuously being exposed to trace amounts of dioxin as exemplified by the fact that virtually all human adipose tissue samples contain dioxin at levels of 3 parts per trillion (ppt) or greater. This paper provides a perspective on MSW incineration as a source of human exposure to dioxin by comparing this exposure source with exposure to background environmental contamination and evaluates some of the potential key sources of PCDD/PCDF input into the enviroment. 32 refs., 3 tabs

  7. Exposure to human-associated fecal indicators and self-reported illness among swimmers at recreational beaches: a cohort study.

    Science.gov (United States)

    Napier, Melanie D; Haugland, Richard; Poole, Charles; Dufour, Alfred P; Stewart, Jill R; Weber, David J; Varma, Manju; Lavender, Jennifer S; Wade, Timothy J

    2017-10-02

    Fecal indicator bacteria used to assess illness risks in recreational waters (e.g., Escherichia coli, Enterococci) cannot discriminate among pollution sources. To address this limitation, human-associated Bacteroides markers have been proposed, but the risk of illness associated with the presence of these markers in recreational waters is unclear. Our objective was to estimate associations between human-associated Bacteroides markers in water and self-reported illness among swimmers at 6 U.S. beaches spanning 2003-2007. We used data from a prospectively-enrolled cohort of 12,060 swimmers surveyed about beach activities and water exposure on the day of their beach visit. Ten to twelve days later, participants reported gastroinestinal, diarrheal, and respiratory illnesses experienced since the visit. Daily water samples were analyzed for the presence of human-associated Bacteroides genetic markers: HF183, BsteriF1, BuniF2, HumM2. We used model-based standardization to estimate risk differences (RD) and 95% confidence intervals (CI). We assessed whether the presence of Bacteroides markers were modifiers of the association between general Enterococcus and illness among swimmers using interaction contrast. Overall we observed inconsistent associations between the presence of Bacteroides markers and illness. There was a pattern of increased risks of gastrointestinal (RD = 1.9%; 95% CI: 0.1%, 3.7%), diarrheal (RD = 1.3%; 95% CI: -0.2%, 2.7%), and respiratory illnesses (RD = 1.1%; 95% CI: -0.2%, 2.5%) associated with BsteriF1. There was no evidence that Bacteroides markers acted as modifiers of Enterococcus and illness. Patterns were similar when stratified by water matrix. Quantitative measures of fecal pollution using Bacteroides, rather than presence-absence indicators, may be necessary to accurately assess human risk specific to the presence of human fecal pollution.

  8. Effects of Moxa (Folium Artemisiae argyi Smoke Exposure on Heart Rate and Heart Rate Variability in Healthy Young Adults: A Randomized, Controlled Human Study

    Directory of Open Access Journals (Sweden)

    Yingxue Cui

    2013-01-01

    Full Text Available Objective. To determine the effects of the moxa smoke on human heart rate (HR and heart rate variability (HRV. Methods. Fifty-five healthy young adults were randomly divided into experimental (n=28 and control (n=27 groups. Experimental subjects were exposed to moxa smoke (2.5 ± 0.5 mg/m3 twice for 25 minutes in one week. ECG monitoring was performed before, during, and after exposure. Control subjects were exposed to normal indoor air in a similar environment and similarly monitored. Followup was performed the following week. Short-term (5 min HRV parameters were analyzed with HRV analysis software. SPSS software was used for statistical analysis. Results. During and after the first exposure, comparison of percentage changes or changes in all parameters between groups showed no significant differences. During the second exposure, percentage decrease in HR, percentage increases in lnTP, lnHF, lnLF, and RMSSD, and increase in PNN50 were significantly greater in the experimental group than in control. Conclusion. No significant adverse HRV effects were associated with this clinically routine 25-minute exposure to moxa smoke, and the data suggests that short-term exposure to moxa smoke might have positive regulating effects on human autonomic function. Further studies are warranted to confirm these findings.

  9. EVALUATION OF A PERSONAL NEPHELOMETER FOR HUMAN EXPOSURE MONITORING

    Science.gov (United States)

    Current particulate matter (PM) exposure studies are using continuous personal nephelometers (pDR-1000, MIE, Inc.) to measure human exposure to PM. The personal nephelometer is a passive sampler which uses light scattering technology to measure particles ranging in size from 0....

  10. Knowledge of human immunodeficiency virus post-exposure ...

    African Journals Online (AJOL)

    2011-05-21

    May 21, 2011 ... Appropriate post-exposure prophylaxis is an integral part of prevention, control and workplace safety. This study was undertaken to assess the level of knowledge of post-exposure prophylaxis (PEP) against human immunodeficiency virus (HIV) among doctors in Federal Medical Centre, Gombe, Nigeria.

  11. Atmospheric Ionizing Radiation and Human Exposure

    Science.gov (United States)

    Wilson, John W.; Mertens, Christopher J.; Goldhagen, Paul; Friedberg, W.; DeAngelis, G.; Clem, J. M.; Copeland, K.; Bidasaria, H. B.

    2005-01-01

    Atmospheric ionizing radiation is of interest, apart from its main concern of aircraft exposures, because it is a principal source of human exposure to radiations with high linear energy transfer (LET). The ionizing radiations of the lower atmosphere near the Earth s surface tend to be dominated by the terrestrial radioisotopes. especially along the coastal plain and interior low lands, and have only minor contributions from neutrons (11 percent). The world average is substantially larger but the high altitude cities especially have substantial contributions from neutrons (25 to 45 percent). Understanding the world distribution of neutron exposures requires an improved understanding of the latitudinal, longitudinal, altitude and spectral distribution that depends on local terrain and time. These issues are being investigated in a combined experimental and theoretical program. This paper will give an overview of human exposures and describe the development of improved environmental models.

  12. Atmospheric Ionizing Radiation and Human Exposure

    Science.gov (United States)

    Wilson, J. W.; Goldhagen, P.; Friedberg, W.; DeAngelis, G.; Clem, J. M.; Copeland, K.; Bidasaria, H. B.

    2004-01-01

    Atmospheric ionizing radiation is of interest, apart from its main concern of aircraft exposures, because it is a principal source of human exposure to radiations with high linear energy transfer (LET). The ionizing radiations of the lower atmosphere near the Earth s surface tend to be dominated by the terrestrial radioisotopes especially along the coastal plain and interior low lands and have only minor contributions from neutrons (11 percent). The world average is substantially larger but the high altitude cities especially have substantial contributions from neutrons (25 to 45 percent). Understanding the world distribution of neutron exposures requires an improved understanding of the latitudinal, longitudinal, altitude and spectral distribution that depends on local terrain and time. These issues are being investigated in a combined experimental and theoretical program. This paper will give an overview of human exposures and describe the development of improved environmental models.

  13. Assessment of Human Exposure to ENMs.

    Science.gov (United States)

    Jiménez, Araceli Sánchez; van Tongeren, Martie

    2017-01-01

    Human exposure assessment of engineered nanomaterials (ENMs) is hampered, among other factors, by the difficulty to differentiate ENM from other nanomaterials (incidental to processes or naturally occurring) and the lack of a single metric that can be used for health risk assessment. It is important that the exposure assessment is carried out throughout the entire life-cycle as releases can occur at the different stages of the product life-cycle, from the synthesis, manufacture of the nano-enable product (occupational exposure) to the professional and consumer use of nano-enabled product (consumer exposure) and at the end of life.Occupational exposure surveys should follow a tiered approach, increasing in complexity in terms of instruments used and sampling strategy applied with higher tiers in order tailor the exposure assessment to the specific materials used and workplace exposure scenarios and to reduce uncertainty in assessment of exposure. Assessment of consumer exposure and of releases from end-of-life processes currently relies on release testing of nano-enabled products in laboratory settings.

  14. Variation in calculated human exposure. Comparison of calculations with seven European human exposure models

    NARCIS (Netherlands)

    Swartjes F; ECO

    2003-01-01

    Twenty scenarios, differing with respect to land use, soil type and contaminant, formed the basis for calculating human exposure from soil contaminants with the use of models contributed by seven European countries (one model per country). Here, the human exposures to children and children

  15. Wood smoke in a controlled exposure experiment with human volunteers

    DEFF Research Database (Denmark)

    Riddervold, Ingunn Skogstad; Bønløkke, Jakob Hjort; Mølhave, Lars

    2011-01-01

    Exposure to wood smoke in the general population is increasing and concurrently, also our awareness. This article describes a wood-smoke generating system for studying human exposure to wood smoke and symptoms related to this exposure. Twenty nonsmoking atopic human participants with normal lung...... function and normal bronchial reactivity were randomly exposed for 3h at three different exposure conditions; clean filtered air (control exposure) and wood smoke with a characteristic particulate matter (PM) concentration of 200 µg/m3 (low) and 400 µg/m3 (high) under controlled environmental conditions.......0007), “irritative body perceptions” (p = 0.0127), “psychological/neurological effects” (p = 0.0075) and “weak inflammatory responses” (p = 0.0003). Furthermore, significant effects (p = 0.0192) on self-reported general mucosa irritation were found. In conclusion, exposure to wood smoke affected symptom rating...

  16. Harmonizing human exposure and toxicity characterization

    DEFF Research Database (Denmark)

    Fantke, Peter; Jolliet, O.; McKone, T.E.

    2017-01-01

    The UNEP-SETAC Life Cycle Initiative has launched a project to provide global guidance and build consensus on environmental life cycle impact assessment (LCIA) indicators. Human health effects from exposure to toxic chemicals was selected as impact category due to high relevance of human toxicity...... and harmonizing human toxicity characterization in LCIA. Building on initial work for the far-field and indoor air environments, and combining it with latest work on near-field consumer and occupational exposure assessment, dose-response and severity data, we aim at providing revised guidance on the development...... and use of impact factors for toxic chemicals. We propose to couple fate processes in consumer and occupational environments with existing environmental compartments and processes via a consistent and mass balance-based set of transfer fractions to quantify overall aggregated exposure to toxic substances...

  17. Chromosomal aberrations in lymphocytes predict human cancer independently of exposure to carcinogens. European Study Group on Cytogenetic Biomarkers and Health

    DEFF Research Database (Denmark)

    Bonassi, S; Hagmar, L; Strömberg, U

    2000-01-01

    An increased risk of cancer in healthy individuals with high levels of chromosomal aberrations (CAs) in peripheral blood lymphocytes has been described in recent epidemiological studies. This association did not appear to be modified by sex, age, country, or time since CA test, whereas the role...... by country, sex, year of birth, and year of CA test were randomly selected. Occupational exposure and smoking habit were assessed by a collaborative group of occupational hygienists. Logistic regression models indicated a statistically significant increase in risk for subjects with a high level of CAs...... compared to those with a low level in the Nordic cohort (odds ratio, 2.35; 95% confidence interval, 1.31-4.23) and in the Italian cohort (odds ratio, 2.66; 95% confidence interval, 1.26-5.62). These estimates were not affected by the inclusion of occupational exposure level and smoking habit...

  18. Comparative Plasma Exposure and Lung Distribution of Two Human Use Commercial Azithromycin Formulations Assessed in Murine Model: A Preclinical Study

    OpenAIRE

    Rivulgo, Virginia Margarita; Sparo, Mónica; Ceci, Mónica; Fumuso, Elida; Confalonieri, Alejandra; Delpech, Gastón; Sanchez Bruni, Sergio Fabian

    2016-01-01

    Azithromycin(AZM)therapeutic failure and relapses of patients treated with generic -35 formulations have been observed in clinical practice.The main goal of this research was 36 to compare in a pre-clinical study the serum exposure and lung tissue concentrationof 37 two commercial formulations AZM-based in murine model. The current study involved 38 264 healthy Balb-C.Mice were divided in two groups (n=44): Animals of Group A 39 (Reference Formulation ?R-) were orally treated with AZM suspens...

  19. Human exposure to low level ionising radiation

    International Nuclear Information System (INIS)

    Paix, David

    1988-01-01

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

  20. The relationship between study sponsorship, risks of bias, and research outcomes in atrazine exposure studies conducted in non-human animals: Systematic review and meta-analysis.

    Science.gov (United States)

    Bero, L; Anglemyer, A; Vesterinen, H; Krauth, D

    2016-01-01

    A critical component of systematic review methodology is the assessment of the risks of bias of studies that are included in the review. There is controversy about whether funding source should be included in a risk of bias assessment of animal toxicology studies. To determine whether industry research sponsorship is associated with methodological biases, the results, or conclusions of animal studies examining the effect of exposure to atrazine on reproductive or developmental outcomes. We searched multiple electronic databases and the reference lists of relevant articles to identify original research studies examining the effect of any dose of atrazine exposure at any life stage on reproduction or development in non-human animals. We compared methodological risks of bias, the conclusions of the studies, the statistical significance of the findings, and the magnitude of effect estimates between industry sponsored and non-industry sponsored studies. Fifty-one studies met the inclusion criteria. There were no differences in methodological risks of bias in industry versus non-industry sponsored studies. 39 studies tested environmentally relevant concentrations of atrazine (11 industry sponsored, 24 non-industry sponsored, 4 with no funding disclosures). Non-industry sponsored studies (12/24, 50.0%) were more likely to conclude that atrazine was harmful compared to industry sponsored studies (2/11, 18.1%) (p value=0.07). A higher proportion of non-industry sponsored studies reported statistically significant harmful effects (8/24, 33.3%) compared to industry-sponsored studies (1/11; 9.1%) (p value=0.13). The association of industry sponsorship with decreased effect sizes for harm outcomes was inconclusive. Our findings support the inclusion of research sponsorship as a risk of bias criterion in tools used to assess risks of bias in animal studies for systematic reviews. The reporting of other empirically based risk of bias criteria for animal studies, such as blinded

  1. EFFECTS OF ARSENIC EXPOSURE IN HUMAN HEALTH

    Directory of Open Access Journals (Sweden)

    Aline Sueli de Lima Rodrigues

    2008-10-01

    Full Text Available In recent years, ingestion of inorganic arsenic from drinking water has emerged as an important public health concern. It enters drinking water supplies from natural deposits in the earth or from agricultural and industrial practices, mainly the mining. The health consequences of chronic arsenic exposure include increased risk for various forms of cancer and numerous pathologic effects, such as cutaneous effects (hyperpigmentation and hyperkeratoses, gastrointestinal effects, vascular effects, diabetes mellitus, and peripheral neuropathy. This way, this study presents through a critical revision of the literature, the more relevant current aspects on the immunological consequences, carcinogenic and resulting genetics of the human intoxication for arsenic. They were identified and analyzed 50 works published on the subject among the years of 1979 and 2008, being used as main sources LILACS-BIREME MEDLINE/Index Medicus, SciELO and PubMed. The specific Arsênio e saúde humana effects of the intoxication for arsenic about the human health are not still completely elucidated. Thus, is possible that this element affects functions still unknown, becoming important the scientificexploration on the subject.

  2. Carcinogen biomonitoring in human exposures and laboratory research: validation and application to human occupational exposures.

    Science.gov (United States)

    Talaska, Glenn; Maier, Andrew; Henn, Scott; Booth-Jones, Angela; Tsuneoka, Yutaka; Vermeulen, Roel; Schumann, Brenda L

    2002-08-05

    A multiple biomarker approach is required to integrate for metabolism, temporal response and exposure-response kinetics, biological relevance, and positive predictive value. Carcinogen DNA adduct analysis can be used in animal and in vitro studies to detect absorption permutations caused by mixture interactions, and to control metabolic variation when specific CYP450 genes (1A1 or 1A2) are knocked out. These enzymes are not critical to the metabolic activation of model Polycyclic Aromatic Compounds (PAC) and aromatic amines, respectively, as suggested by in vitro analysis. Several human studies have been carried out where multiple biomarkers have been measured. In a study of benzidine workers, the similarities in elimination kinetics between urinary metabolites and mutagenicity is likely responsible for a better correlation between these markers than to BZ-DNA adducts in exfoliated cells. In a study of rubber workers, the relationship between specific departments, urinary 1 HP and DNA adducts in exfoliated cells coincided with the historical urinary bladder cancer risk in these departments; the same relationship did not hold for urinary mutagenicity. In a study of automotive mechanics, biomarkers were used to monitor the effectiveness of exposure interventions. These data reinforce the notion that carcinogen biomarkers are useful to monitor exposure, but that a complementary approaches involving effect and perhaps susceptibility biomarkers is necessary to obtain the necessary information.

  3. Relative significance of natural irradiation vs all human exposures

    International Nuclear Information System (INIS)

    Jammet, H.

    1985-01-01

    A review is made of the fundamentals allowing to quantitatively express the importance of the various sources of human exposure by an individual or collective approach. Following a summary of the components of normal exposure to natural sources, the various human actions at the origin of enhanced exposure are studied: 1) those modifying the relationship between natural sources and man (dwelling conditions, coal burning, geothermal energy production, exploitation of phosphate rock); 2) those creating new artificial sources (nuclear explosions in the atmosphere, nuclear power production, medical use of radiation and radionuclides). The effective dose equivalent commitments for these sources are compared with those necessarily involved by continuous normal exposure to the natural sources of exposure [fr

  4. Early androgen exposure and human gender development.

    Science.gov (United States)

    Hines, Melissa; Constantinescu, Mihaela; Spencer, Debra

    2015-01-01

    During early development, testosterone plays an important role in sexual differentiation of the mammalian brain and has enduring influences on behavior. Testosterone exerts these influences at times when the testes are active, as evidenced by higher concentrations of testosterone in developing male than in developing female animals. This article critically reviews the available evidence regarding influences of testosterone on human gender-related development. In humans, testosterone is elevated in males from about weeks 8 to 24 of gestation and then again during early postnatal development. Individuals exposed to atypical concentrations of testosterone or other androgenic hormones prenatally, for example, because of genetic conditions or because their mothers were prescribed hormones during pregnancy, have been consistently found to show increased male-typical juvenile play behavior, alterations in sexual orientation and gender identity (the sense of self as male or female), and increased tendencies to engage in physically aggressive behavior. Studies of other behavioral outcomes following dramatic androgen abnormality prenatally are either too small in their numbers or too inconsistent in their results, to provide similarly conclusive evidence. Studies relating normal variability in testosterone prenatally to subsequent gender-related behavior have produced largely inconsistent results or have yet to be independently replicated. For studies of prenatal exposures in typically developing individuals, testosterone has been measured in single samples of maternal blood or amniotic fluid. These techniques may not be sufficiently powerful to consistently detect influences of testosterone on behavior, particularly in the relatively small samples that have generally been studied. The postnatal surge in testosterone in male infants, sometimes called mini-puberty, may provide a more accessible opportunity for measuring early androgen exposure during typical development. This

  5. Post-exposure rabies prophylaxis in humans exposed to animals in Lublin province (Eastern Poland) in 2012-2015 - A retrospective study.

    Science.gov (United States)

    Krzowska-Firych, Joanna; Tomasiewicz, Krzysztof; Kozøowska, Agata

    2017-06-03

    Rabies continues to be one of the most important viral diseases and remains a significant threat to public health across the globe. The post-exposure prophylaxis in humans can effectively prevent death after exposure to a potentially infected animal. In Poland, recommendations for rabies PEP followed the national guidelines which recommend that people should receive PEP when bitten by an animal suspected to be infected by rabies. PEP in humans includes cleansing and disinfecting the wound or point of contact, and administering anti-rabies immunization. Rabies vaccine should be given for contacts of category II and category III exposures. RIG should be given for category III contact. The vaccination schedule includes 5 doses given within a 30 day period (the Essen regimen). The aim of our study was to determine the frequency of post-exposure prophylaxis among patients exposed to animals and also to assess the animal species suspected as a source of rabies exposure. We have retrospectively analyzed medical records from the years 2012-2015 of all adult patients who were exposed to animals and consulted at the Dispensary of Rabies Prophylaxis in the Department of Infectious Diseases at the Medical University in Lublin, Poland. All consulted patients were asked to give an informed consent in case of decision to use collected data for future research work. Ethical approval was obtained from the Ethics Committee of the Medical University of Lublin, Poland, and all patients included in this study gave an informed consent during consultation after the exposure to animals. During the studied 4-year period, 511 persons exposed to animals were consulted and prophylactic procedure consisting of active immunization were applied in 54.2% of the total consulted. Dogs and cats were the most common animal species suspected as the source of the rabies exposure. Anti-rabies prophylaxis was applied in 45.8% of all vaccinated patients exposed to dogs, and in 24.2% exposed to cats. All

  6. Analysis of coupled model uncertainties in source-to-dose modeling of human exposures to ambient air pollution: A PM 2.5 case study

    Science.gov (United States)

    Özkaynak, Halûk; Frey, H. Christopher; Burke, Janet; Pinder, Robert W.

    Quantitative assessment of human exposures and health effects due to air pollution involve detailed characterization of impacts of air quality on exposure and dose. A key challenge is to integrate these three components on a consistent spatial and temporal basis taking into account linkages and feedbacks. The current state-of-practice for such assessments is to exercise emission, meteorology, air quality, exposure, and dose models separately, and to link them together by using the output of one model as input to the subsequent downstream model. Quantification of variability and uncertainty has been an important topic in the exposure assessment community for a number of years. Variability refers to differences in the value of a quantity (e.g., exposure) over time, space, or among individuals. Uncertainty refers to lack of knowledge regarding the true value of a quantity. An emerging challenge is how to quantify variability and uncertainty in integrated assessments over the source-to-dose continuum by considering contributions from individual as well as linked components. For a case study of fine particulate matter (PM 2.5) in North Carolina during July 2002, we characterize variability and uncertainty associated with each of the individual concentration, exposure and dose models that are linked, and use a conceptual framework to quantify and evaluate the implications of coupled model uncertainties. We find that the resulting overall uncertainties due to combined effects of both variability and uncertainty are smaller (usually by a factor of 3-4) than the crudely multiplied model-specific overall uncertainty ratios. Future research will need to examine the impact of potential dependencies among the model components by conducting a truly coupled modeling analysis.

  7. Study of the oncogenic expression in human fibroblast cells after exposure to very short pulsed laser radiations

    International Nuclear Information System (INIS)

    Dormont, D.; Freville, Th.; Raoul, H.; Courant, D.; Court, L.

    1992-01-01

    The aim of this study is to evaluate the capacity of a laser, delivering very short pulses in the near infrared spectrum with a high pulse ratio frequency, to induce genetic modification on biological tissues. The absence of dicentric among chromosomal aberrations on human lymphocytes suggests that a repetitive very short pulses irradiation has a relatively low capacity to induce genetic abnormalities. The studies of the radiation effects on the cellular growth and the oncogenic expression show that the modifications, induced at the cellular level, do not seem the origin of a cellular transformation and a possible mechanism of carcinogenesis. (author)

  8. In vivo x-ray fluorescence of bone lead in the study of human lead metabolism: Serum lead, whole blood lead, bone lead, and cumulative exposure

    International Nuclear Information System (INIS)

    Cake, K.M.; Chettle, D.R.; Webber, C.E.; Gordon, C.L.

    1995-01-01

    Traditionally, clinical studies of lead's effect on health have relied on blood lead levels to indicate lead exposure. However, this is unsatisfactory because blood lead levels have a half-life of approximately 5 weeks, and thus reflect recent exposure. Over 90% of the lead body burden is in bone, and it is thought to have a long residence time, thus implying that measurements of bone lead reflect cumulative exposure. So, measurements of bone lead are useful in understanding the long-term health effects of lead. Ahlgren reported the first noninvasive measurements of bone lead in humans, where γ-rays from 57 Co were used to excite the K series x-rays of lead. The lead detection system at McMaster University uses a 109 Cd source which is positioned at the center of the detector face (HPGe) and a near backscatter (∼160 degrees) geometry. This arrangement allows great flexibility, since one can sample lead in a range of different bone sites due to a robust normalization technique which eliminates the need to correct for bone geometry, thickness of overlying tissue, and other related factors. The effective radiation dose to an adult during an x-ray fluorescence bone lead measurement is extremely low, being 35 nSv. This paper addresses the issue of how bone, whole blood, and serum lead concentrations can be related in order to understand a person's lead exposure history

  9. Western Canada beef productivity study : a component of the western Canada study on animal and human health effects associated with exposure to emissions from oil and natural gas field facilities : study design

    International Nuclear Information System (INIS)

    2001-11-01

    A study was conducted to determine if exposure from oil and gas emissions has an impact on animal and human health in western Canada. The study design has been reviewed and endorsed by the Science Advisory Panel of the Western Interprovincial Scientific Studies Association which is composed of 10 internationally renowned scientists with experience in environmental and reproductive epidemiology, animal and human health, and toxicology. The research methodology includes a peer review process to ensure credibility. The five components of the study include: beef cattle productivity; assessment of the immune function in beef cattle; assessment of wildlife reproduction and immune function; exposure monitoring; and, human health. This study provides insight beyond that gained from previous studies. The association between flaring and reproductive outcomes in beef herds was examined. The association between herd location in high sulfur deposition areas and increased risk of reproductive failure was also evaluated. The study includes exposure markers for both sweet gas emissions and sour gas sources. Passive monitors measured volatile organic carbons such as benzene, toluene, ethylbenzene, and xylene. Monitoring was also conducted for other compounds including sulphur dioxide, hydrogen sulphide, particulate matter, and polycyclic aromatic hydrocarbons. Final analysis and assessment of the data should be complete by late 2003 with a report available for peer review at the beginning of 2004. refs

  10. Sampling strategy for estimating human exposure pathways to consumer chemicals

    Directory of Open Access Journals (Sweden)

    Eleni Papadopoulou

    2016-03-01

    Full Text Available Human exposure to consumer chemicals has become a worldwide concern. In this work, a comprehensive sampling strategy is presented, to our knowledge being the first to study all relevant exposure pathways in a single cohort using multiple methods for assessment of exposure from each exposure pathway. The selected groups of chemicals to be studied are consumer chemicals whose production and use are currently in a state of transition and are; per- and polyfluorinated alkyl substances (PFASs, traditional and “emerging” brominated flame retardants (BFRs and EBFRs, organophosphate esters (OPEs and phthalate esters (PEs. Information about human exposure to these contaminants is needed due to existing data gaps on human exposure intakes from multiple exposure pathways and relationships between internal and external exposure. Indoor environment, food and biological samples were collected from 61 participants and their households in the Oslo area (Norway on two consecutive days, during winter 2013-14. Air, dust, hand wipes, and duplicate diet (food and drink samples were collected as indicators of external exposure, and blood, urine, blood spots, hair, nails and saliva as indicators of internal exposure. A food diary, food frequency questionnaire (FFQ and indoor environment questionnaire were also implemented. Approximately 2000 samples were collected in total and participant views on their experiences of this campaign were collected via questionnaire. While 91% of our participants were positive about future participation in a similar project, some tasks were viewed as problematic. Completing the food diary and collection of duplicate food/drink portions were the tasks most frequent reported as “hard”/”very hard”. Nevertheless, a strong positive correlation between the reported total mass of food/drinks in the food record and the total weight of the food/drinks in the collection bottles was observed, being an indication of accurate performance

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

    International Nuclear Information System (INIS)

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

    1984-11-01

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

  12. Inhale while Dreaming: Human Exposure to Pollutants while Sleeping

    DEFF Research Database (Denmark)

    Corsi, Richard; Spilak, Michal; Boor, E., Brandon

    2012-01-01

    of indoor pollutants, e.g., flame retardants to isocyanates. As such, there is a need for increased dialogue on this subject, end-point relevant research, and action to reduce exposures to high-risk contaminants for most of humanity. This workshop will involve an opening 5–minute presentation related...... discussion related to practical implications of new findings as well as past studies, geographic variations in emissions from mattresses and beddings, methods for reducing population exposures, and suggestions for future research that has practical endpoints and that can lead to reduced exposures....

  13. Foetal exposure to food and environmental carcinogens in human beings.

    Science.gov (United States)

    Myöhänen, Kirsi; Vähäkangas, Kirsi

    2012-02-01

    Exposure to many different chemicals during pregnancy through maternal circulation is possible. Transplacental transfer of xenobiotics can be demonstrated using human placental perfusion. Also, placental perfusion can give information about the placental kinetics as well as metabolism and accumulation in the placenta because it retains the tissue structure and function. Although human placental perfusion has been used extensively to study the transplacental transfer of drugs, the information on food and environmental carcinogens is much more limited. This review deals with the foetal exposure to food and environmental carcinogens in human beings. In particular, human transplacental transfer of the food carcinogens such as acrylamide, glycidamide and nitrosodimethylamine are in focus. Because these carcinogens are genotoxic, the functional capacity of human placenta to induce DNA adduct formation or metabolize these above mentioned CYP2E1 substrates is of interest in this context. © 2011 The Authors. Basic & Clinical Pharmacology & Toxicology © 2011 Nordic Pharmacological Society.

  14. Human exposure limits to hypergolic fuels

    Science.gov (United States)

    Garcia, H. D.; James, J. T.; Limero, T. F.

    1992-01-01

    Over the past four decades, many studies have been conducted on the toxicities of the rocket propellants hydrazine (HZ) and monomethylhydrazine (MH). Numerous technical challenges have made it difficult to unambiguously interpret the results of these studies, and there is considerable divergence between results obtained by different investigators on the inhalation concentrations (MAC's) for each toxic effect inducible by exposure to hypergolic fuels in spacecraft atmospheres, NASA undertook a critical review of published and unpublished investigations on the toxicities of these compounds. The current state of the art practices for similar studies. While many questions remain unanswered, MAC's were determined using the best available data for a variety of toxic endpoints for potential continuous exposure durations ranging from 1 hour to 180 days. Spacecraft MAC's (SMAC's) were set for each compound based on the most sensitive toxic endpoint at each exposure duration.

  15. Assessment of human dietary exposure to arsenic through rice.

    Science.gov (United States)

    Davis, Matthew A; Signes-Pastor, Antonio J; Argos, Maria; Slaughter, Francis; Pendergrast, Claire; Punshon, Tracy; Gossai, Anala; Ahsan, Habibul; Karagas, Margaret R

    2017-05-15

    Rice accumulates 10-fold higher inorganic arsenic (i-As), an established human carcinogen, than other grains. This review summarizes epidemiologic studies that examined the association between rice consumption and biomarkers of arsenic exposure. After reviewing the literature we identified 20 studies, among them included 18 observational and 2 human experimental studies that reported on associations between rice consumption and an arsenic biomarker. Among individuals not exposed to contaminated water, rice is a source of i-As exposure - rice consumption has been consistently related to arsenic biomarkers, and the relationship has been clearly demonstrated in experimental studies. Early-life i-As exposure is of particular concern due to its association with lifelong adverse health outcomes. Maternal rice consumption during pregnancy also has been associated with infant toenail total arsenic concentrations indicating that dietary exposure during pregnancy results in fetal exposure. Thus, the collective evidence indicates that rice is an independent source of arsenic exposure in populations around the world and highlights the importance of investigating its affect on health. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  16. National Surveillance of Occupational Exposure to the Human Immunodeficiency Virus

    Directory of Open Access Journals (Sweden)

    Maura Ricketts

    1992-01-01

    Full Text Available In September 1985, a prospective study was initiated to monitor the occurrence of occupational exposures to human immunodeficiency virus (HIV-infected blood and body fluids in Canada. This program was coordinated by the Federal Centre for acquired immune deficiency syndrome (AIDS (now the Division of HIV/AIDS Epidemiology at the Laboratory Centre for Disease Control. The objective was to determine the risk to workers of acquiring HIV infection as a result of exposure to HIV-infected blood and other body fluids. To be eligible, a worker must have sustained a documented parenteral, mucous membrane or skin contact exposure to blood or body fluids from an HIV-infected person. A baseline specimen was collected within a week of the exposure and then at six weeks, 12 weeks, six months and 12 months. Information concerning the type of exposure, precautions used and post exposure treatment was submitted to the Federal Centre for AIDS on standard data collection forms. All information was anonymous, identified only by a code number. Guidelines for counselling an exposed employee were provided with enrollment material. As of July 29, 1991, 414 employees have been included in the study. Two hundred and thirty-seven of the 414 exposures (57% were needlestick injuries of which 167 (70% were sustained by nurses. Other exposures consisted of open wound contamination, eye splashes, scalpel wounds and skin contact with blood and body fluids. To date, there have been no seroconversions among workers enrolled in the surveillance program.

  17. 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...

  18. Effects of RF-EMF Exposure from GSM Mobile Phones on Proliferation Rate of Human Adipose-derived Stem Cells: An In-vitro Study

    Directory of Open Access Journals (Sweden)

    Shahbazi-Gahrouei D

    2016-12-01

    Full Text Available Background: As the use of mobile phones is increasing, public concern about the harmful effects of radiation emitted by these devices is also growing. In addition, protection questions and biological effects are among growing concerns which have remained largely unanswered. Stem cells are useful models to assess the effects of radiofrequency electromagnetic fields (RF-EMF on other cell lines. Stem cells are undifferentiated biological cells that can differentiate into specialized cells. Adipose tissue represents an abundant and accessible source of adult stem cells. The aim of this study is to investigate the effects of GSM 900 MHz on growth and proliferation of mesenchymal stem cells derived from adipose tissue within the specific distance and intensity. Materials and Methods: ADSCs were exposed to GSM mobile phones 900 MHz with intensity of 354.6 µW/cm2 square waves (217 Hz pulse frequency, 50% duty cycle, during different exposure times ranging from 6 to 21 min/day for 5 days at 20 cm distance from the antenna. MTT assay was used to determine the growth and metabolism of cells and trypan blue test was also done for cell viability. Statistical analyses were carried out using analysis of one way ANOVA. P<0.05 was considered to be statistically significant. Results: The proliferation rates of human ADSCs in all exposure groups were significantly lower than control groups (P<0.05 except in the group of 6 minutes/day which did not show any significant difference with control groups. Conclusion: The results show that 900 MHz RF signal radiation from antenna can reduce cell viability and proliferation rates of human ADSCs regarding the duration of exposure.

  19. Human reproductive system disturbances and pesticide exposure in Brazil

    Directory of Open Access Journals (Sweden)

    Koifman Sergio

    2002-01-01

    Full Text Available The observation of reproductive disturbances in humans and in the wildlife has been reported in the last decade in different countries. Exposure to different chemicals possibly acting in the endocrine system or endocrine disruptors, including pesticides, has been a hypothesis raised to explain the observed changes. This paper aimed to present results of an epidemiological ecologic study carried out to explore population data on pesticides exposure in selected Brazilian states in the eighties and human reproductive outcomes in the nineties. Pearson correlation coefficients were ascertained between available data pesticides sales in eleven states in Brazil in 1985 and selected further reproductive outcomes or their surrogates. Moderate to high correlations were observed to infertility, testis, breast, prostate and ovarian cancer mortality. Despite the restrains of ecologic studies to establish cause-effect relationships, the observed results are in agreement with evidence supporting a possible association between pesticides exposure and the analyzed reproductive outcomes.

  20. Assessment of Nicotine Exposure From Active Human Cigarette Smoking Time

    Directory of Open Access Journals (Sweden)

    Cahours Xavier

    2017-09-01

    Full Text Available The burning of a cigarette is a series of consecutive sequences of both passive and active burnings when a smoking cycle is applied to the cigarette. A previous study, using a smoking machine, showed that cigarette nicotine yields are dependent linearly on the difference between the time of smouldering (passive burning and the time of smoking (active burning. It is predicted that the smoker’s nicotine yield increases when the intensity of smoking increases, i.e., when the time to smoke a cigarette (smoking time decreases. Note that observations made on machines might not be comparable to human behaviours. The aim of this study was to determine whether nicotine mouth-level exposure could be predicted through measurement of human smoking time. A smoking behaviour study was conducted to compare human smoking nicotine yields obtained from both filter tip analysis and the cigarette burning time model. Results showed that smokers’ exposure to the smoke depends essentially on the speed at which the cigarette is smoked. An increase in human smoking intensity, resulting in a decrease in smoking time, generates an increase in smoke exposure, whatever the puff number, puff duration, puff volume and filter ventilation (open or blocked. The association of a machine smoking yield with a corresponding smoking time, and the time taken by a consumer to smoke the cigarette would provide information on the exposure to smoke constituents in a simple and effective manner.

  1. Quantifying human exposure to air pollution - moving from static monitoring to spatio-temporally resolved personal exposure assessment

    DEFF Research Database (Denmark)

    Steinle, Susanne; Reis, Stefan; Sabel, Clive E

    2013-01-01

    exposure studies to accurately assess human health risks. ? We discuss potential and shortcomings of methods and tools with a focus on how their development influences study design. ? We propose a novel conceptual model for integrated health impact assessment of human exposure to air pollutants. ? We......Quantifying human exposure to air pollutants is a challenging task. Ambient concentrations of air pollutants at potentially harmful levels are ubiquitous in urban areas and subject to high spatial and temporal variability. At the same time, every individual has unique activity-patterns. Exposure...... results from multifaceted relationships and interactions between environmental and human systems, adding complexity to the assessment process. Traditionally, approaches to quantify human exposure have relied on pollutant concentrations from fixed air quality network sites and static population...

  2. EVALUATION OF EMF EXPOSURE OF MOBILE PHONES ON HUMAN HEAD

    Directory of Open Access Journals (Sweden)

    N. I. Vtornikova

    2017-01-01

    Full Text Available Introduction. Mobile phones are worldwide spread nowadays. Smartphones penetration is growing year after year. Numerous studies indicate the negative effect of EMF exposure of these devices on humans. Therefore, it is important to study the peculiarities of their influence on the target organ-the brain. It is important for solving this problem to find out the real situation of the distribution of energy flux density (EFD of EMF exposure near the front panel of the apparatus.The aim of the study is to determine and compare EMF exposure from smartphones and classic mobile phones on human head.Material and methods. The original method patented in the Russian Federation was used in this study. The used original measuring setup is also patented, developed and assembled by the authors of the study. The object of the study was classical mobile phones and smartphones widespread at the time of work.Results. We got the graphic of matrices of distribution of energy flux density (EFD of EMF exposure in the plane against the front panel of 10 apparatus corresponding to the topography of a human head. The study revealed peculiarities of this distribution in smartphones and the classic mobile phones and got the values of energy flux density (EFD of EMF exposure in the investigated devices acting primarily on the brain.Conclusions. The design of smartphones and mobile phones determines the overall picture of distribution of EFD of EMF exposure in the plane against the front panel for devices of a particular type. This picture must be taken into account when planning epidemiological and experimental studies to obtain comparable results. Progress in the development of mobile communication technologies has led to an increase in the electromagnetic load on users of modern devices.

  3. Effects of tobacco smoke and electronic cigarette vapor exposure on the oral and gut microbiota in humans: a pilot study.

    Science.gov (United States)

    Stewart, Christopher J; Auchtung, Thomas A; Ajami, Nadim J; Velasquez, Kenia; Smith, Daniel P; De La Garza, Richard; Salas, Ramiro; Petrosino, Joseph F

    2018-01-01

    The use of electronic cigarettes (ECs) has increased drastically over the past five years, primarily as an alternative to smoking tobacco cigarettes. However, the adverse effects of acute and long-term use of ECs on the microbiota have not been explored. In this pilot study, we sought to determine if ECs or tobacco smoking alter the oral and gut microbiota in comparison to non-smoking controls. We examined a human cohort consisting of 30 individuals: 10 EC users, 10 tobacco smokers, and 10 controls. We collected cross-sectional fecal, buccal swabs, and saliva samples from each participant. All samples underwent V4 16S rRNA gene sequencing. Tobacco smoking had a significant effect on the bacterial profiles in all sample types when compared to controls, and in feces and buccal swabs when compared to EC users. The most significant associations were found in the gut, with an increased relative abundance of Prevotella ( P = 0.006) and decreased Bacteroides ( P = 0.036) in tobacco smokers. The Shannon diversity was also significantly reduced ( P = 0.009) in fecal samples collected from tobacco smokers compared to controls. No significant difference was found in the alpha diversity, beta-diversity or taxonomic relative abundances between EC users and controls. From a microbial ecology perspective, the current pilot data demonstrate that the use of ECs may represent a safer alternative compared to tobacco smoking. However, validation in larger cohorts and greater understanding of the short and long-term impact of EC use on microbiota composition and function is warranted.

  4. Effects of tobacco smoke and electronic cigarette vapor exposure on the oral and gut microbiota in humans: a pilot study

    Directory of Open Access Journals (Sweden)

    Christopher J. Stewart

    2018-04-01

    Full Text Available Background The use of electronic cigarettes (ECs has increased drastically over the past five years, primarily as an alternative to smoking tobacco cigarettes. However, the adverse effects of acute and long-term use of ECs on the microbiota have not been explored. In this pilot study, we sought to determine if ECs or tobacco smoking alter the oral and gut microbiota in comparison to non-smoking controls. Methods We examined a human cohort consisting of 30 individuals: 10 EC users, 10 tobacco smokers, and 10 controls. We collected cross-sectional fecal, buccal swabs, and saliva samples from each participant. All samples underwent V4 16S rRNA gene sequencing. Results Tobacco smoking had a significant effect on the bacterial profiles in all sample types when compared to controls, and in feces and buccal swabs when compared to EC users. The most significant associations were found in the gut, with an increased relative abundance of Prevotella (P = 0.006 and decreased Bacteroides (P = 0.036 in tobacco smokers. The Shannon diversity was also significantly reduced (P = 0.009 in fecal samples collected from tobacco smokers compared to controls. No significant difference was found in the alpha diversity, beta-diversity or taxonomic relative abundances between EC users and controls. Discussion From a microbial ecology perspective, the current pilot data demonstrate that the use of ECs may represent a safer alternative compared to tobacco smoking. However, validation in larger cohorts and greater understanding of the short and long-term impact of EC use on microbiota composition and function is warranted.

  5. Human Bisphenol A Exposure and the “Diabesity Phenotype”

    Science.gov (United States)

    Leone, Alessandro; Battezzati, Alberto

    2015-01-01

    Bisphenol A (BPA), a known endocrine disruptor, is a food contaminant suspected of being a contributing factor to the present-day increase in obesity, diabetes, and cardiovascular disease. This issue is of increasing interest in the field of diabetes research and has become a matter of concern for regulatory agencies and food industries. Recently, the number of studies involving BPA has increased exponentially, but there are still many gaps in the knowledge of the relationship between actual BPA exposure and cardiometabolic risk and of the modalities of food intake exposure, all of which prevents sound judgments concerning the risks to human health. This review focuses on the association between human exposure to BPA and obesity, thyroid function, diabetes, insulin resistance, metabolic syndrome, cardiovascular diseases, and BPA content in food. Many cross-sectional studies support, sometimes contradictorily, an adverse effect of BPA exposure on obesity, diabetes, and cardiovascular diseases. Few prospective studies support an adverse effect of BPA exposure on such pathologies. Moreover, no intervention studies have been conducted to evaluate the causality of such associations. This is mainly due to lack of an appropriate database of BPA content in foods, thus hindering any estimation of the usual dietary BPA intake. PMID:26858585

  6. Human exposure to emissions from building materials

    DEFF Research Database (Denmark)

    Kjærgaard, S.; Hauschildt, P.; Pejtersen, Jan

    1999-01-01

    found on peak flow, eye foam formation, tear fluid cells, or conjunctival epithelial damage. Among subjective evaluations only sound intensity rating was significant. A correlation was found between acute nose irritation rating and change in nasal volume.Conclusions. The findings indicate physiological......Objectives. Reactions to emissions from building matrials were studied in a climate chamber as part of an intervention study in an office building. New and existing flooring materials were compared with regard to comfort and health.Methods. Twenty subjects were exposed four times for six hours...... respectively to clean air, to emissions from linoleum, from carpet, and from an alternative new vinyl. Measurements of objective and subjective effects were made.Results. Tear film stability decreased after exposure to linoleum. The nasal volume decreased near-significantly for all exposures. No effects were...

  7. Novel brominated flame retardants in food composites and human milk from the Chinese Total Diet Study in 2011: Concentrations and a dietary exposure assessment.

    Science.gov (United States)

    Shi, Zhixiong; Zhang, Lei; Li, Jingguang; Zhao, Yunfeng; Sun, Zhiwei; Zhou, Xianqing; Wu, Yongning

    2016-11-01

    On the basis of the fifth Chinese total diet study (TDS) performed in 2011, the dietary exposure of the Chinese population to novel brominated flame retardants (NBFRs) was assessed. Six NBFRs were determined in 80 composite samples from four animal origin food groups and 29 pooled human milk samples. Based on gas chromatography-negative chemical ionization mass spectrometry (GC-NCI/MS) analysis, the levels of the total NBFRs ranged from human milk samples. Decabromodiphenyl ethane (DBDPE), with mean levels of 9.03ng/g lw in food composites and 8.06ng/g lw in human milk, was the most abundant compound in the total NBFRs. No obvious spatial distribution patterns in China were observed in food samples or human milk. The average estimated daily intake (EDI) of total NBFRs via food consumption for a "standard Chinese man" was 4.77ng/kg bodyweight (bw)/day, with a range of 0.681 to 18.9ng/kgbw/day. Meat and meat products were the main dietary source of NBFRs, although levels of NBFRs in aquatic food were found to be the highest among the four food groups. The average EDI of total NBFRs for nursing infants was 38.4ng/kgbw/day, with a range of 17.4 to 113ng/kgbw/day, which was approximately eight-fold higher than the EDI for adults, suggesting the heavy body burden of NBFRs on nursing infants. The levels and EDI of DBDPE in the present study were similar to or higher than those of legacy BFRs (i.e., PBDEs and HBCD) in the TDS 2007, indicating that DBDPE, as a main alternative to PBDEs, might have become the primary BFR used in China. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. HIV infection and domestic smoke exposure, but not human papillomavirus, are risk factors for esophageal squamous cell carcinoma in Zambia: a case–control study

    International Nuclear Information System (INIS)

    Kayamba, Violet; Bateman, Allen C; Asombang, Akwi W; Shibemba, Aaron; Zyambo, Kanekwa; Banda, Themba; Soko, Rose; Kelly, Paul

    2015-01-01

    There is emerging evidence that esophageal cancer occurs in younger adults in sub-Saharan Africa than in Europe or North America. The burden of human immunodeficiency virus (HIV) is also high in this region. We postulated that HIV and human papillomavirus (HPV) infections might contribute to esophageal squamous cell carcinoma (OSCC) risk. This was a case–control study based at the University Teaching Hospital in Lusaka, Zambia. Cases were patients with confirmed OSCC and controls had completely normal upper endoscopic evaluations. A total of 222 patients were included to analyze the influence of HIV infection; of these, 100 patients were used to analyze the influence of HPV infection, alcohol, smoking, and exposure to wood smoke. The presence of HIV infection was determined using antibody kits, and HPV infection was detected by polymerase chain reaction. HIV infection on its own conferred increased risk of developing OSCC (odds ratio [OR] 2.3; 95% confidence interval [CI] 1.0–5.1; P = 0.03). The OR was stronger when only people under 60 years were included (OR 4.3; 95% CI 1.5–13.2; P = 0.003). Cooking with charcoal or firewood, and cigarette smoking, both increased the odds of developing OSCC ([OR 3.5; 95% CI 1.4–9.3; P = 0.004] and [OR 9.1; 95% CI 3.0–30.4; P < 0.001], respectively). There was no significant difference in HPV detection or alcohol intake between cases and controls. We conclude that HIV infection and exposure to domestic and cigarette smoke are risk factors for OSCC, and HPV immunization unlikely to reduce OSCC incidence in Zambia

  9. Biocides Steering Group on human exposure assessment: a preliminary report.

    Science.gov (United States)

    van Hemmen, J J

    1999-06-30

    In a project granted by DG XI of the European Commission, it is attempted to collate experimental and theoretical data on human (workers and consumers) exposure assessment to biocidal products, and to outline the methodology for sampling and measurement. On the basis of the available evidence, approaches are presented for the exposure assessment to be used for estimation of risks in authorization procedures under the recently accepted Directive 98/8/EC. Gaps in knowledge are indicated, making it possible to study the issues involved in a comprehensive and cost-effective way. Some recommendations are given on how to best do this. The current project has been detailed in a final report.

  10. Identifying Housing and Meteorological Conditions Influencing Residential Air Exchange Rates in the DEARS and RIOPA Studies: Development of Distributions for Human Exposure Modeling

    Science.gov (United States)

    Appropriate prediction of residential air exchange rate (AER) is important for estimating human exposures in the residential microenvironment, as AER drives the infiltration of outdoor-generated air pollutants indoors. AER differences among homes may result from a number of fact...

  11. Silver percutaneous absorption after exposure to silver nanoparticles: a comparison study of three human skin graft samples used for clinical applications.

    Science.gov (United States)

    Bianco, C; Adami, G; Crosera, M; Larese, F; Casarin, S; Castagnoli, C; Stella, M; Maina, G

    2014-11-01

    Silver nanoparticles (AgNPs) are increasingly applied to a wide range of materials for biomedical use. These enable a close contact with human skin, thanks to the large release of silver ions that is responsible for a broad spectrum of antimicrobial activity. Silver can permeate the skin; however, there are no data available on silver permeation through skin grafts commonly used in burns recovery. The aim of our study was to evaluate silver penetration using fresh, cryopreserved, and glycerolized human skin grafts after exposure to a suspension of AgNPs in synthetic sweat using a Franz diffusion cell apparatus for 24 h. Silver permeation profiles revealed a significantly higher permeation through glycerolized skin compared with both fresh and cryopreserved skin: 24-h silver flux penetration was 0.2 ng cm(-2) h(-1) (lag time: 8.2 h) for fresh skin, 0.3 ng cm(-2) h(-1) (lag time: 10.9 h) for cryopreserved skin, and 3.8 ng cm(-2) h(-1) (lag time: 6.3 h) for glycerolized skin. Permeation through glycerolized skin is significantly higher compared to both fresh and cryopreserved skin. This result can generate relevant clinical implications for burns treatment with products containing AgNPs. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  12. Ozone exposure increases respiratory epithelial permeability in humans

    International Nuclear Information System (INIS)

    Kehrl, H.R.; Vincent, L.M.; Kowalsky, R.J.; Horstman, D.H.; O'Neil, J.J.; McCartney, W.H.; Bromberg, P.A.

    1987-01-01

    Ozone is a respiratory irritant that has been shown to cause an increase in the permeability of the respiratory epithelium in animals. We used inhaled aerosolized /sup 99m/Tc-labeled diethylene triamine pentacetic acid (/sup 99m/Tc-DTPA) to investigate whether human respiratory epithelial permeability is similarly affected by exposure to ozone. In a randomized, crossover double-blinded study, 8 healthy, nonsmoking young men were exposed for 2 h to purified air and 0.4 ppm ozone while performing intermittent high intensity treadmill exercise (minute ventilation = 66.8 L/min). SRaw and FVC were measured before and at the end of exposures. Seventy-five minutes after the exposures, the pulmonary clearance of /sup 99m/Tc-DTPA was measured by sequential posterior lung imaging with a computer-assisted gamma camera. Ozone exposure caused respiratory symptoms in all 8 subjects and was associated with a 14 +/- 2.8% (mean +/- SEM) decrement in FVC (p less than 0.001) and a 71 +/- 22% increase in SRaw (p = 0.04). Compared with the air exposure day, 7 of the 8 subjects showed increased /sup 99m/Tc-DTPA clearance after the ozone exposure, with the mean value increasing from 0.59 +/- 0.08 to 1.75 +/- 0.43%/min (p = 0.03). These data show that ozone exposure sufficient to produce decrements in the pulmonary function of human subjects also causes an increase in /sup 99m/Tc-DTPA clearance

  13. DIETARY CHARACTERIZATIONS IN A STUDY OF HUMAN EXPOSURES IN THE LOWER RIO GRANDE VALLEY: I. FOODS AND BEVERAGES

    Science.gov (United States)

    The Lower Rio Grande Valley Environmental Study (LRGVES), a cooperative effort between various federal and state agencies, responded to concerns of the local community about possible adverse health effects related to environmental conditions. The LRGVES pilot project, conducted d...

  14. [Effects of radiation exposure on human body].

    Science.gov (United States)

    Kamiya, Kenji; Sasatani, Megumi

    2012-03-01

    There are two types of radiation health effect; acute disorder and late on-set disorder. Acute disorder is a deterministic effect that the symptoms appear by exposure above a threshold. Tissues and cells that compose the human body have different radiation sensitivity respectively, and the symptoms appear in order, from highly radiosensitive tissues. The clinical symptoms of acute disorder begin with a decrease in lymphocytes, and then the symptoms appear such as alopecia, skin erythema, hematopoietic damage, gastrointestinal damage, central nervous system damage with increasing radiation dose. Regarding the late on-set disorder, a predominant health effect is the cancer among the symptoms of such as cancer, non-cancer disease and genetic effect. Cancer and genetic effect are recognized as stochastic effects without the threshold. When radiation dose is equal to or more than 100 mSv, it is observed that the cancer risk by radiation exposure increases linearly with an increase in dose. On the other hand, the risk of developing cancer through low-dose radiation exposure, less 100 mSv, has not yet been clarified scientifically. Although uncertainty still remains regarding low level risk estimation, ICRP propound LNT model and conduct radiation protection in accordance with LNT model in the low-dose and low-dose rate radiation from a position of radiation protection. Meanwhile, the mechanism of radiation damage has been gradually clarified. The initial event of radiation-induced diseases is thought to be the damage to genome such as radiation-induced DNA double-strand breaks. Recently, it is clarified that our cells could recognize genome damage and induce the diverse cell response to maintain genome integrity. This phenomenon is called DNA damage response which induces the cell cycle arrest, DNA repair, apoptosis, cell senescence and so on. These responses act in the direction to maintain genome integrity against genome damage, however, the death of large number of

  15. Naphthalene distributions and human exposure in Southern California

    Science.gov (United States)

    Lu, Rong; Wu, Jun; Turco, Richard P.; Winer, Arthur M.; Atkinson, Roger; Arey, Janet; Paulson, Suzanne E.; Lurmann, Fred W.; Miguel, Antonio H.; Eiguren-Fernandez, Arantzazu

    The regional distribution of, and human exposure to, naphthalene are investigated for Southern California. A comprehensive approach is taken in which advanced models are linked for the first time to quantify population exposure to the emissions of naphthalene throughout Southern California. Naphthalene is the simplest and most abundant of the polycyclic aromatic hydrocarbons found in polluted urban environments, and has been detected in both outdoor and indoor air samples. Exposure to high concentrations of naphthalene may have adverse health effects, possibly causing cancer in humans. Among the significant emission sources are volatilization from naphthalene-containing products, petroleum refining, and combustion of fossil fuels and wood. Gasoline and diesel engine exhaust, with related vaporization from fuels, are found to contribute roughly half of the daily total naphthalene burden in Southern California. As part of this study, the emission inventory for naphthalene has been verified against new field measurements of the naphthalene-to-benzene ratio in a busy traffic tunnel in Los Angeles, supporting the modeling work carried out here. The Surface Meteorology and Ozone Generation (SMOG) airshed model is used to compute the spatial and temporal distributions of naphthalene and its photooxidation products in Southern California. The present simulations reveal a high degree of spatial variability in the concentrations of naphthalene-related species, with large diurnal and seasonal variations as well. Peak naphthalene concentrations are estimated to occur in the early morning hours in the winter season. The naphthalene concentration estimates obtained from the SMOG model are employed in the Regional Human Exposure (REHEX) model to calculate population exposure statistics. Results show average hourly naphthalene exposures in Southern California under summer and winter conditions of 270 and 430 ng m -3, respectively. Exposure to significantly higher concentrations

  16. Polybrominated Diphenyl Ethers in Human Milk and Serum from the U.S. EPA MAMA Study: Modeled Predictions of Infant Exposure and Considerations for Risk Assessment

    Science.gov (United States)

    Marchitti, Satori A.; Fenton, Suzanne E.; Mendola, Pauline; Kenneke, John F.; Hines, Erin P.

    2016-01-01

    Background: Serum concentrations of polybrominated diphenyl ethers (PBDEs) in U.S. women are believed to be among the world’s highest; however, little information exists on the partitioning of PBDEs between serum and breast milk and how this may affect infant exposure. Objectives: Paired milk and serum samples were measured for PBDE concentrations in 34 women who participated in the U.S. EPA MAMA Study. Computational models for predicting milk PBDE concentrations from serum were evaluated. Methods: Samples were analyzed using gas chromatography isotope-dilution high-resolution mass spectrometry. Observed milk PBDE concentrations were compared with model predictions, and models were applied to NHANES serum data to predict milk PBDE concentrations and infant intakes for the U.S. population. Results: Serum and milk samples had detectable concentrations of most PBDEs. BDE-47 was found in the highest concentrations (median serum: 18.6; milk: 31.5 ng/g lipid) and BDE-28 had the highest milk:serum partitioning ratio (2.1 ± 0.2). No evidence of depuration was found. Models demonstrated high reliability and, as of 2007–2008, predicted U.S. milk concentrations of BDE-47, BDE-99, and BDE-100 appear to be declining but BDE-153 may be rising. Predicted infant intakes (ng/kg/day) were below threshold reference doses (RfDs) for BDE-99 and BDE-153 but above the suggested RfD for BDE-47. Conclusions: Concentrations and partitioning ratios of PBDEs in milk and serum from women in the U.S. EPA MAMA Study are presented for the first time; modeled predictions of milk PBDE concentrations using serum concentrations appear to be a valid method for estimating PBDE exposure in U.S. infants. Citation: Marchitti SA, Fenton SE, Mendola P, Kenneke JF, Hines EP. 2017. Polybrominated diphenyl ethers in human milk and serum from the U.S. EPA MAMA Study: modeled predictions of infant exposure and considerations for risk assessment. Environ Health Perspect 125:706–713; http://dx.doi.org/10

  17. Post exposure prophylaxis against human immunodeficiency virus ...

    African Journals Online (AJOL)

    2015-11-23

    Nov 23, 2015 ... Abstract: Objective: To deter- mine the level of awareness, knowledge and practice of human immunodeficiency virus post ex- posure prophylaxis (HIV PEP) among paediatricians in Nigeria. Methodology: The study was a cross sectional questionnaire- based survey conducted among paediatrcians that ...

  18. Human exposure to bovine polyomavirus: a zoonosis

    Energy Technology Data Exchange (ETDEWEB)

    Parry, J V; Gardner, S D

    1986-01-01

    A competitive-type solid phase radioimmunoassay (RIA) was developed for the detection of antibody to bovine polyomavirus. Comparison of RIA and counter-immunoelectrophoresis (CIE) results on 273 cattle sera indicated that both techniques were detecting antibody of like specificity. Human sera from 256 blood donors, 219 people recently vaccinated against polio, rubella or rabies, 50 immunosuppressed patients and 472 people with various occupational exposure to cattle were tested for antibody to bovine polyomavirus, the foetal rhesus monkey kidney strain, (anti-FRKV) by RIA. Apart from one blood donor and one of 108 rabies vaccinees only those in close contact with cattle possessed anti-FRKV. Compared with 62 per cent seropositive in the natural hosts, cattle, 71 per cent of veterinary surgeons, 50 per cent of cattle farmers, 40 per cent of abattoir workers, 16 per cent of veterinary institute technical staff and 10 per cent of veterinary students were anti-FRKV positive. Our findings indicate that the theoretical hazard of FRKV infection from undetected contamination of current tissue culture derived vaccines may, in practice, be remote. Proposed wider use of primate kidney cells as substrates for new vaccines may increase this risk.

  19. Exposure to perfluorinated compounds and human semen quality in Arctic and European populations

    DEFF Research Database (Denmark)

    Toft, G; Jönsson, B A G; Lindh, C H

    2012-01-01

    Perfluorinated compounds (PFCs) have been suspected to adversely affect human reproductive health. The aim of this study was to investigate the associations between PFC exposure and male semen quality.......Perfluorinated compounds (PFCs) have been suspected to adversely affect human reproductive health. The aim of this study was to investigate the associations between PFC exposure and male semen quality....

  20. Sun exposure and vitamin D supplementation in relation to vitamin D status of breastfeeding mothers and infants in the global exploration of human milk study.

    Science.gov (United States)

    Dawodu, Adekunle; Davidson, Barbara; Woo, Jessica G; Peng, Yong-Mei; Ruiz-Palacios, Guillermo M; de Lourdes Guerrero, Maria; Morrow, Ardythe L

    2015-02-05

    Although vitamin D (vD) deficiency is common in breastfed infants and their mothers during pregnancy and lactation, a standardized global comparison is lacking. We studied the prevalence and risk factors for vD deficiency using a standardized protocol in a cohort of breastfeeding mother-infant pairs, enrolled in the Global Exploration of Human Milk Study, designed to examine longitudinally the effect of environment, diet and culture. Mothers planned to provide breast milk for at least three months post-partum and were enrolled at four weeks postpartum in Shanghai, China (n=112), Cincinnati, Ohio (n=119), and Mexico City, Mexico (n=113). Maternal serum 25(OH)D was measured by radioimmunoassay (obesity (p=0.03), season (p=0.001) and sites (p<0.001) predicted maternal vD status. vD deficiency in order of magnitude was found in 62%, 28%, and 6% of Mexican, Cincinnati and Shanghai infants, respectively (p<0.001). Season (p=0.022), adding formula feeding (p<0.001) and a higher sun index (p=0.085) predicted higher infant vD status. vD deficiency appears to be a global problem in mothers and infants, though the prevalence in diverse populations may depend upon sun exposure behaviors and vD supplementation. Greater attention to maternal and infant vD status starting during pregnancy is warranted worldwide.

  1. Progress in human exposure assessment for biocidal products

    NARCIS (Netherlands)

    Hemmen, J.J. van

    2004-01-01

    An important shortcoming in our present knowledge required for risk assessment of biocidal products is the assessment of human exposure. This knowledge gap has been filled in a preliminary fashion with the TNsG on human exposure to biocidal products (available from the ECB website). Explicit User

  2. Human exposure assessment: Approaches for chemicals (REACH) and biocides (BPD)

    NARCIS (Netherlands)

    Hemmen, J.J. van; Gerritsen-Ebben, R.

    2008-01-01

    The approaches that are indicated in the various guidance documents for the assessment of human exposure for chemicals and biocides are summarised. This reflects the TNsG (Technical notes for Guidance) version 2: human exposure assessment for biocidal products (1) under the BPD (Biocidal Products

  3. A Margin-of-Exposure Approach to Assessment of Noncancer Risks of Dioxins Based on Human Exposure and Response Data

    OpenAIRE

    Aylward, Lesa L.; Goodman, Julie E.; Charnley, Gail; Rhomberg, Lorenz R.

    2008-01-01

    Background Risk assessment of human environmental exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDFs) and other dioxin-like compounds is complicated by several factors, including limitations in measuring intakes because of the low concentrations of these compounds in foods and the environment and interspecies differences in pharmacokinetics and responses. Objectives We examined the feasibility of relying directly on human studies of exposure and potential responses to...

  4. Human Exposure Risk Assessment Due to Heavy Metals in Groundwater by Pollution Index and Multivariate Statistical Methods: A Case Study from South Africa

    OpenAIRE

    Vetrimurugan Elumalai; K. Brindha; Elango Lakshmanan

    2017-01-01

    Heavy metals in surface and groundwater were analysed and their sources were identified using multivariate statistical tools for two towns in South Africa. Human exposure risk through the drinking water pathway was also assessed. Electrical conductivity values showed that groundwater is desirable to permissible for drinking except for six locations. Concentration of aluminium, lead and nickel were above the permissible limit for drinking at all locations. Boron, cadmium, iron and manganese ex...

  5. Cytogenetic adaptive response induced by pre-exposure in human lymphocytes and marrow cells of mice

    International Nuclear Information System (INIS)

    Zhang Lianzhen; Deng Zhicheng

    1993-01-01

    The cytogenetic adaptive response induced by pre-exposure in human lymphocytes and marrow cells of mice were studied. The results of this study showed that human lymphocytes in vitro and mouse marrow cells in vivo can become adapted to low-level irradiation from 3 H-TdR or exposure to a low dose of X-or γ-irradiation, so that they become less sensitive to the chromosomal damage effects of subsequent exposures. (4 tabs.)

  6. Comprehensive Study of Human External Exposure to Organophosphate Flame Retardants via Air, Dust, and Hand Wipes: The Importance of Sampling and Assessment Strategy.

    Science.gov (United States)

    Xu, Fuchao; Giovanoulis, Georgios; van Waes, Sofie; Padilla-Sanchez, Juan Antonio; Papadopoulou, Eleni; Magnér, Jorgen; Haug, Line Småstuen; Neels, Hugo; Covaci, Adrian

    2016-07-19

    We compared the human exposure to organophosphate flame retardants (PFRs) via inhalation, dust ingestion, and dermal absorption using different sampling and assessment strategies. Air (indoor stationary air and personal ambient air), dust (floor dust and surface dust), and hand wipes were sampled from 61 participants and their houses. We found that stationary air contains higher levels of ΣPFRs (median = 163 ng/m(3), IQR = 161 ng/m(3)) than personal air (median = 44 ng/m(3), IQR = 55 ng/m(3)), suggesting that the stationary air sample could generate a larger bias for inhalation exposure assessment. Tris(chloropropyl) phosphate isomers (ΣTCPP) accounted for over 80% of ΣPFRs in both stationary and personal air. PFRs were frequently detected in both surface dust (ΣPFRs median = 33 100 ng/g, IQR = 62 300 ng/g) and floor dust (ΣPFRs median = 20 500 ng/g, IQR = 30 300 ng/g). Tris(2-butoxylethyl) phosphate (TBOEP) accounted for 40% and 60% of ΣPFRs in surface and floor dust, respectively, followed by ΣTCPP (30% and 20%, respectively). TBOEP (median = 46 ng, IQR = 69 ng) and ΣTCPP (median = 37 ng, IQR = 49 ng) were also frequently detected in hand wipe samples. For the first time, a comprehensive assessment of human exposure to PFRs via inhalation, dust ingestion, and dermal absorption was conducted with individual personal data rather than reference factors of the general population. Inhalation seems to be the major exposure pathway for ΣTCPP and tris(2-chloroethyl) phosphate (TCEP), while participants had higher exposure to TBOEP and triphenyl phosphate (TPHP) via dust ingestion. Estimated exposure to ΣPFRs was the highest with stationary air inhalation (median =34 ng·kg bw(-1)·day(-1), IQR = 38 ng·kg bw(-1)·day(-1)), followed by surface dust ingestion (median = 13 ng·kg bw(-1)·day(-1), IQR = 28 ng·kg bw(-1)·day(-1)), floor dust ingestion and personal air inhalation. The median dermal exposure on hand wipes was 0.32 ng·kg bw(-1)·day(-1) (IQR

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-05-15

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

  8. Human Exposure Risk Assessment Due to Heavy Metals in Groundwater by Pollution Index and Multivariate Statistical Methods: A Case Study from South Africa

    Directory of Open Access Journals (Sweden)

    Vetrimurugan Elumalai

    2017-04-01

    Full Text Available Heavy metals in surface and groundwater were analysed and their sources were identified using multivariate statistical tools for two towns in South Africa. Human exposure risk through the drinking water pathway was also assessed. Electrical conductivity values showed that groundwater is desirable to permissible for drinking except for six locations. Concentration of aluminium, lead and nickel were above the permissible limit for drinking at all locations. Boron, cadmium, iron and manganese exceeded the limit at few locations. Heavy metal pollution index based on ten heavy metals indicated that 85% of the area had good quality water, but 15% was unsuitable. Human exposure dose through the drinking water pathway indicated no risk due to boron, nickel and zinc, moderate risk due to cadmium and lithium and high risk due to silver, copper, manganese and lead. Hazard quotients were high in all sampling locations for humans of all age groups, indicating that groundwater is unsuitable for drinking purposes. Highly polluted areas were located near the coast, close to industrial operations and at a landfill site representing human-induced pollution. Factor analysis identified the four major pollution sources as: (1 industries; (2 mining and related activities; (3 mixed sources- geogenic and anthropogenic and (4 fertilizer application.

  9. Major national human biomonitoring programs in chemical exposure assessment

    Directory of Open Access Journals (Sweden)

    Judy Choi

    2015-07-01

    Full Text Available Human biomonitoring (HBM programs have been established in several countries around the world in order to monitor the levels of chemical exposures in the general population and qualify health risk assessment of national and international interest. Study design, population, sample collection, and chemical analysis must be considered when comparing and interpreting the results. In this review, the objectives and brief descriptions of the major national HBM programs in North America, Europe, and Asia are provided. Similarities and differences observed from a comparative analysis among these programs, including the stratification of data according to age, sex, socioeconomic background, etc. as well as the identification of chemical exposure associated with food intake, are discussed. Overall, although there are some discrepancies in the study designs among the reviewed national HBM programs, results from the programs can provide useful information such as chemical levels found within the general population of a country that can be compared. Furthermore, the results can be used by regulatory authorities or the government to enforce legislations in order to reduce the exposure of chemicals into the human body.

  10. Pre-exposure Prophylaxis Against Human Immunodeficiency Virus

    Directory of Open Access Journals (Sweden)

    Güle ÇINAR

    2018-03-01

    Full Text Available According to the Center for Disease Control and Prevention (CDC, there were 2.1 million new human immunodeficiency virus (HIV cases reported worldwide in 2015, which shows that siginificant work needs to be done to prevent the transmission of HIV. Research to date has focused mainly on high-risk men who have sex with men, but many women around the world are also at a high risk for HIV transmissions. In studies conducted, the incidence of HIV infection in high-risk individuals decreases over 90% when high-risk individuals use pre-exposure prophylaxis (PreP HIV, tenofovir disoproxil fumarate-emtricitabine (TDF-FTC safely. Current data and studies on pre-exposure prophylaxis were discussed in this review.

  11. Human performance analysis of industrial radiography radiation exposure events

    International Nuclear Information System (INIS)

    Reece, W.J.; Hill, S.G.

    1995-01-01

    A set of radiation overexposure event reports were reviewed as part of a program to examine human performance in industrial radiography for the US Nuclear Regulatory Commission. Incident records for a seven year period were retrieved from an event database. Ninety-five exposure events were initially categorized and sorted for further analysis. Descriptive models were applied to a subset of severe overexposure events. Modeling included: (1) operational sequence tables to outline the key human actions and interactions with equipment, (2) human reliability event trees, (3) an application of an information processing failures model, and (4) an extrapolated use of the error influences and effects diagram. Results of the modeling analyses provided insights into the industrial radiography task and suggested areas for further action and study to decrease overexposures

  12. Respiratory effects of particulate matter air pollution: studies on diesel exhaust, road tunnel, subway and wood smoke exposure in human subjects

    Energy Technology Data Exchange (ETDEWEB)

    Sehlstedt, Maria

    2011-07-01

    Background: Ambient air pollution is associated with adverse health effects, but the sources and components, which cause these effects is still incompletely understood. The aim of this thesis was to investigate the pulmonary effects of a variety of common air pollutants, including diesel exhaust, biomass smoke, and road tunnel and subway station environments. Healthy non-smoking volunteers were exposed in random order to the specific air pollutants and air/control, during intermittent exercise, followed by bronchoscopy. Methods and results: In study I, exposures were performed with diesel exhaust (DE) generated at transient engine load and air for 1 hour with bronchoscopy at 6 hours post-exposure. Immunohistochemical analyses of bronchial mucosal biopsies showed that DE exposure significantly increased the endothelial adhesion molecule expression of p-selectin and VCAM-1, together with increased bronchoalveolar lavage (BAL) eosinophils. In study II, the subjects were exposed for 1 hour to DE generated during idling with bronchoscopy at 6 hours. The bronchial mucosal biopsies showed significant increases in neutrophils, mast cells and lymphocytes together with bronchial wash neutrophils. Additionally, DE exposure significantly increased the nuclear translocation of the aryl hydrocarbon receptor (AhR) and phosphorylated c-jun in the bronchial epithelium. In contrast, the phase II enzyme NAD(P)H-quinone oxidoreductase 1 (NQO1) decreased after DE. In study III, the 2-hour exposures took place in a road tunnel with bronchoscopy 14 hours later. The road tunnel exposure significantly increased the total numbers of lymphocytes and alveolar macrophages in BAL, whereas NK cell and CD56+/T cell numbers significantly decreased. Additionally, the nuclear expression of phosphorylated c-jun in the bronchial epithelium was significantly increased after road tunnel exposure. In study IV, the subjects were exposed to metal-rich particulate aerosol for 2 hours at a subway station

  13. Arsenic exposure and calpain-10 polymorphisms impair the function of pancreatic beta-cells in humans: a pilot study of risk factors for T2DM.

    Directory of Open Access Journals (Sweden)

    Andrea Díaz-Villaseñor

    Full Text Available The incidence of type 2 diabetes mellitus (T2DM is increasing worldwide and diverse environmental and genetic risk factors are well recognized. Single nucleotide polymorphisms (SNPs in the calpain-10 gene (CAPN-10, which encodes a protein involved in the secretion and action of insulin, and chronic exposure to inorganic arsenic (iAs through drinking water have been independently associated with an increase in the risk for T2DM. In the present work we evaluated if CAPN-10 SNPs and iAs exposure jointly contribute to the outcome of T2DM. Insulin secretion (beta-cell function and insulin sensitivity were evaluated indirectly through validated indexes (HOMA2 in subjects with and without T2DM who have been exposed to a gradient of iAs in their drinking water in northern Mexico. The results were analyzed taking into account the presence of the risk factor SNPs SNP-43 and -44 in CAPN-10. Subjects with T2DM had significantly lower beta-cell function and insulin sensitivity. An inverse association was found between beta-cell function and iAs exposure, the association being more pronounced in subjects with T2DM. Subjects without T2DM who were carriers of the at-risk genotype SNP-43 or -44, also had significantly lower beta-cell function. The association of SNP-43 with beta-cell function was dependent on iAs exposure, age, gender and BMI, whereas the association with SNP-44 was independent of all of these factors. Chronic exposure to iAs seems to be a risk factor for T2DM in humans through the reduction of beta-cell function, with an enhanced effect seen in the presence of the at-risk genotype of SNP-43 in CAPN-10. Carriers of CAPN-10 SNP-44 have also shown reduced beta-cell function.

  14. Autopsy tissues as biological monitors of human exposure to environmental pollutants. A case study: Concentrations of metals and PCDD/Fs in subjects living near a hazardous waste incinerator.

    Science.gov (United States)

    Domingo, José L; García, Francisco; Nadal, Martí; Schuhmacher, Marta

    2017-04-01

    Human biomonitoring is of tremendous importance to prevent potential adverse effects derived from human exposure to chemicals. Blood and urine are among the biological monitors more frequently used. However, biological matrices such as breast milk, hair, nails, saliva, feces, teeth, and expired air are also often used. In addition, and focused mainly on long-term exposure, adipose tissue and other human tissues like bone, liver, brain or kidney, are also used as biological monitors of certain substances, especially for long-term biomonitoring. However, for this kind of tissues sampling is always a limiting factor. In this paper, we have examined the role of autopsy tissues as biological monitors of human exposure to environmental pollutants. For it, we have used a case study conducted near a hazardous waste incinerator (HWI) in Catalonia (Spain), in which the concentrations of metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), have been periodically determined in autopsy tissues of subjects living in the area under potential influence of the facility. This case study does not show advantages -in comparison to other appropriate biomonitors such as blood- in using autopsy tissues in the monitoring of long-term exposure to metals and PCDD/Fs. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. TSPY4 is a novel sperm-specific biomarker of semen exposure in human cervicovaginal fluids; potential use in HIV prevention and contraception studies.

    Science.gov (United States)

    Jacot, Terry A; Zalenskaya, Irina; Mauck, Christine; Archer, David F; Doncel, Gustavo F

    2013-09-01

    Developing an objective, reliable method to determine semen exposure in cervicovaginal fluids is important for accurately studying the efficacy of vaginal microbicides and contraceptives. Y-chromosome biomarkers offer better stability, sensitivity, and specificity than protein biomarkers. TSPY4 belongs to the TSPY (testis-specific protein Y-encoded) family of homologous genes on the Y-chromosome. Using a multiplex PCR amplifying TSPY4, amelogenin, and Sex-determining region in the Y chromosome (SRY), our objective was to determine whether a gene in the TSPY family was a more sensitive marker of semen exposure in cervicovaginal fluids than SRY. The multiplex polymerase chain reaction (PCR) was developed using sperm and vaginal epithelial (female) DNA. Diluted sperm DNA and mixed male/female DNA was used to determine the sensitivity of the multiplex PCR. Potential interference of TSPY4 amplification by components in cervicovaginal and seminal fluids was determined. TSPY4 and SRY amplification was also investigated in women participating in a separate IRB-approved clinical study in which cervicovaginal swab DNA was collected before semen exposure and at various time points after exposure. TSPY4, SRY, and amelogenin were amplified in sperm DNA, but only amelogenin in female DNA. The limit of sperm DNA from which TSPY4 could be amplified was lower than SRY (4 pg vs 80 pg). TSPY4 could also be amplified from mixed male/female DNA. Amplification was not affected by cervicovaginal and seminal components. Using cervicovaginal swab DNA from three women before and after semen exposure, TSPY4 was detected up to 72 h post exposure while SRY detection was observed up to 24-48 h. TSPY4 was detected up to 7 days post exposure in one out of three women. We have demonstrated that TSPY4 is a new sensitive, and sperm-specific biomarker. The multiplex PCR incorporating this new biomarker has potential to be an objective measure for determining semen exposure in clinical trials of

  16. Environmental chemical exposures and human epigenetics

    Science.gov (United States)

    Hou, Lifang; Zhang, Xiao; Wang, Dong; Baccarelli, Andrea

    2012-01-01

    Every year more than 13 million deaths worldwide are due to environmental pollutants, and approximately 24% of diseases are caused by environmental exposures that might be averted through preventive measures. Rapidly growing evidence has linked environmental pollutants with epigenetic variations, including changes in DNA methylation, histone modifications and microRNAs. Environ mental chemicals and epigenetic changes All of these mechanisms are likely to play important roles in disease aetiology, and their modifications due to environmental pollutants might provide further understanding of disease aetiology, as well as biomarkers reflecting exposures to environmental pollutants and/or predicting the risk of future disease. We summarize the findings on epigenetic alterations related to environmental chemical exposures, and propose mechanisms of action by means of which the exposures may cause such epigenetic changes. We discuss opportunities, challenges and future directions for future epidemiology research in environmental epigenomics. Future investigations are needed to solve methodological and practical challenges, including uncertainties about stability over time of epigenomic changes induced by the environment, tissue specificity of epigenetic alterations, validation of laboratory methods, and adaptation of bioinformatic and biostatistical methods to high-throughput epigenomics. In addition, there are numerous reports of epigenetic modifications arising following exposure to environmental toxicants, but most have not been directly linked to disease endpoints. To complete our discussion, we also briefly summarize the diseases that have been linked to environmental chemicals-related epigenetic changes. PMID:22253299

  17. Relative biological effectiveness if alpha radiation for human lung exposure

    International Nuclear Information System (INIS)

    Yarmoshenko, I.; Kirdin, I.; Zhukovsky, M.

    2006-01-01

    Full text of publication follows: The concept of RBE, which introduced by ICRP and ICRU about 50 years ago to compare biological effects of ionizing radiation of different types, still continues to be the essential element of current and projected radiation protection systems in terms of deriving quantities (quality factor and radiation weighting factor). For example, RBE for the stochastic effects induction has to be considered for appropriate radiation weighting of the absorbed dose while estimating equivalent dose. Simulation of lung cancer radiation risk for the cases of inhalation of radon progeny and incorporation of plutonium in lung in comparison with external reference radiation allows assessment of RBE for alpha-radiation. Specific radiation risk models were developed by results of the direct epidemiological studies and used for such simulation. Simulation included published risk models for nuclear workers of the Mayak facilities in the former Soviet Union exposed to incorporated plutonium (Kreisheimer et al., 2003; Gilbert et al., 2004) and underground miners exposed to radon progenies (BEIR VI, 1999). Additionally lung cancer risk model was developed for a case of population indoor radon exposure. Lung cancer risk related to external exposure is estimated using the risk model develop ed using data of Life Span Study of Japanese atomic bomb survivors. By results of lifetime lung cancer risk simulation using Monte Carlo approach estimated median value of RBE in case of indoor radon exposure is 1.5 (with 90% range 0.4 to 7). In case of the two models developed by BEIR VI for lung cancer risk due to radon exposure in underground miners the median values of RBE are 2.1 and 4.4 (with 90% ranges 0.3 to 17 and 0.7 to 45) respectively.Two different models for lung cancer risk related to plutonium exposure resulted in close estimates of RBE: median value of 12 and 13 (with 90% range 4 to 104 and 4 to 136) respectively. Considerable discrepancy between RBE

  18. Use of human bronchial epithelial cells (BEAS-2B) to study immunological markers resulting from exposure to PM2.5 organic extract from Puerto Rico

    International Nuclear Information System (INIS)

    Fuentes-Mattei, Enrique; Rivera, Evasomary; Gioda, Adriana; Sanchez-Rivera, Diana; Roman-Velazquez, Felix R.; Jimenez-Velez, Braulio D.

    2010-01-01

    Fine particulate air pollutants, mainly their organic fraction, have been demonstrated to be associated with cardiovascular and respiratory health problems. Puerto Rico has been reported to have the highest prevalence of pulmonary diseases (e.g., asthma) in the United States. The aim of this study was to assess, for the first time, the immunological response of human bronchial epithelial cells (BEAS-2B) to organic extracts isolated from airborne particulate matter (PM 2.5 ) in Puerto Rico. Organic extracts from PM 2.5 collected throughout an 8-month period (2000-2001) were pooled (composite) in order to perform chemical analysis and biological activity testing. BEAS-2B cells were exposed to PM 2.5 organic extract to assess cytotoxicity, levels of cytokines and relative gene expression of MHC-II, hPXR and CYP3A5. Our findings show that organic PM 2.5 consist of toxic as well as bioactive components that can regulate the secretion of cytokines in BEAS-2B, which could modulate inflammatory response in the lung. Trace element analyses confirmed the presence of metals in organic extracts highlighting the relative high abundance of Cu and Zn in polar organic extracts. Polar organic extracts exhibited dose-dependant toxicity and were found to significantly induce the release of interleukin 6 (IL-6), IL-1β and IL-7 while significantly inhibiting the secretion of IL-8, G-CSF and MCP-1. Moreover, MHC-II transcriptional activity was up-regulated after 24 h of exposure, whereas PXR and CYP3A5 were down-regulated. This research provides a new insight into the effects of PM 2.5 organic fractions on specific effectors and their possible role in the development of respiratory inflammatory diseases in Puerto Rico.

  19. Quantifying human exposure to air pollution--moving from static monitoring to spatio-temporally resolved personal exposure assessment.

    Science.gov (United States)

    Steinle, Susanne; Reis, Stefan; Sabel, Clive Eric

    2013-01-15

    Quantifying human exposure to air pollutants is a challenging task. Ambient concentrations of air pollutants at potentially harmful levels are ubiquitous in urban areas and subject to high spatial and temporal variability. At the same time, every individual has unique activity-patterns. Exposure results from multifaceted relationships and interactions between environmental and human systems, adding complexity to the assessment process. Traditionally, approaches to quantify human exposure have relied on pollutant concentrations from fixed air quality network sites and static population distributions. New developments in sensor technology now enable us to monitor personal exposure to air pollutants directly while people are moving through their activity spaces and varying concentration fields. The literature review on which this paper is based on reflects recent developments in the assessment of human exposure to air pollution. This includes the discussion of methodologies and concepts, and the elaboration of approaches and study designs applied in the field. We identify shortcomings of current approaches and discuss future research needs. We close by proposing a novel conceptual model for the integrated assessment of human exposure to air pollutants taking into account latest technological capabilities and contextual information. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Human Health Effects Associated with Exposure to Toxic Cyanobacteria

    Science.gov (United States)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-08-15

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

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

    International Nuclear Information System (INIS)

    Zhao, Fei; Severson, Paul; Pacheco, Samantha; Futscher, Bernard W.; Klimecki, Walter T.

    2013-01-01

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

  3. Biomonitoring human exposure to environmental carcinogenic chemicals

    DEFF Research Database (Denmark)

    Farmer, P.B.; Sepai, O.; Lawrence, R.

    1996-01-01

    for detecting carcinogen-induced damage to DNA and proteins, and subsequent biological effects. These methods were validated with the occupational exposures, which showed evidence of DNA and/or protein and/or chromosome damage in workers in a coke oven plant, garage workers exposed to diesel exhaust and workers...

  4. Skin absorption and human exposure estimation of three widely discussed UV filters in sunscreens--In vitro study mimicking real-life consumer habits.

    Science.gov (United States)

    Klimová, Z; Hojerová, J; Beránková, M

    2015-09-01

    Due to health concerns about safety, three UV-filters (Benzophenone-3, BP3, 10%; Ethylhexyl Methoxycinnamate, EHMC, 10%; Butyl Methoxydibenzoylmethane, BMDBM; 5%) were examined in vitro for absorption on full-thickness pig-ear skin, mimicking human in-use conditions. Kinetic profiles confirmed the rapid permeation of BP3; after the first hour of skin (frozen-stored) exposure to 2 mg/cm(2) (W/O sunscreen; recommended but unrealistic amount), about 0.5% of the applied dose passed into the receptor fluid. The absorption rate of filters was higher from W/O than from O/W emulsions. The fresh/frozen-stored skin permeability coefficient (0.83-0.54) for each UV filter was taken into account. Systemic Exposure Dosage of BP3, EHMC, BMDBM for humans as a consequence of (i) whole-body and (ii) face treatment with 0.5 mg/cm(2) of W/O sunscreen for 6-h skin exposure followed by washing and subsequent 18-h permeation (a realistic scenario) were estimated to be (i) 4744, 1032 and 1036 μg/kg-bw/day, and (ii) 153, 33 and 34 μg/kg-bw/day, respectively. From Margin of Safety for BP3, EHMC and BMDBM (i) 42, 485 and 192 as well as (ii) 1307; 15,151 and 5882, respectively, only the value of 42 (<100) for BP3 indicated a possible health risk. Escalation of a phobia towards all organic UV filters is undesirable. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Y-12 Uranium Exposure Study

    Energy Technology Data Exchange (ETDEWEB)

    Eckerman, K.F.; Kerr, G.D.

    1999-08-05

    Following the recent restart of operations at the Y-12 Plant, the Radiological Control Organization (RCO) observed that the enriched uranium exposures appeared to involve insoluble rather than soluble uranium that presumably characterized most earlier Y-12 operations. These observations necessitated changes in the bioassay program, particularly the need for routine fecal sampling. In addition, it was not reasonable to interpret the bioassay data using metabolic parameter values established during earlier Y-12 operations. Thus, the recent urinary and fecal bioassay data were interpreted using the default guidance in Publication 54 of the International Commission on Radiological Protection (ICRP); that is, inhalation of Class Y uranium with an activity median aerodynamic diameter (AMAD) of 1 {micro}m. Faced with apparently new workplace conditions, these actions were appropriate and ensured a cautionary approach to worker protection. As additional bioassay data were accumulated, it became apparent that the data were not consistent with Publication 54. Therefore, this study was undertaken to examine the situation.

  6. Eco-toxicity and human estrogenic exposure risks from "·OH-initiated photochemical transformation of four phthalates in water: A computational study

    International Nuclear Information System (INIS)

    Gao, Yanpeng; An, Taicheng; Ji, Yuemeng; Li, Guiying; Zhao, Cunyuan

    2015-01-01

    Transformation products (TPs) of emerging organic contaminates (EOCs) in water are still rarely considered in environmental risk assessment, although some have been found to be concern. "·OH is believed as an important reactive species both in indirect phototransformation and advanced oxidation technology. Thus, eco-toxicity and human estrogenic exposure risks of four phthalates and TPs during the "·OH-initiated photochemical process were investigated using computational approach. Four phthalates can be degraded through "·OH-addition and H-transfer pathways. The "·OH-addition TPs were predominant for dimethyl phthalates, while H-transfer TPs were predominant for other three phthalates. Compared with phthalates, "·OH-addition TPs (o-OH-phthalates) were one level more toxic to aquatic organisms, and m-OH-phthalates exhibit higher estrogenic activity. Although H-transfer TPs were less harmful than "·OH-addition TPs, some of them still have aquatic toxicity and estrogenic activity. Therefore, more attentions should be paid to photochemical TPs and original EOCs, particularly those exhibiting high estrogenic activity to humans. - Highlights: • Phthalates can be degraded with "·OH-addition and H-transfer pathways. • "·OH-addition products are mainly formed during DMP transformation. • H-transfer products were predominant for the transformation of DEP, DPP and DBP. • o-"·OH-addition products have greater eco-toxicity than corresponding phthalates. • m-"·OH-addition products have higher estrogenic activity than corresponding phthalates. - Computational approach could provide valuable information on the mechanisms, kinetics, eco-toxicity as well as human estrogenic exposure risks of EOCs and their transformation products.

  7. Human Health and Exposure to Electromagnetic Radiation

    Science.gov (United States)

    1992-07-01

    passed through volunteers from electrodes attached to their heads and bodies while they were subjected to a series of psychological tests (Bonnell et...al, 1985; Stollery, 1986). The pattern of current was equivalent to that produced by exposure to a 36 kV m- 1 field at 50 Hz. The psychological tests ...Silverman, 1977; Lilienfeld et al, 1978; Stopps and Janischewsky, 1979; Knave et al, 1979; Robinette et al, 1980; Marsh et al, 1982; Silverman, 1985

  8. Natural radiation exposure modified by human activities

    International Nuclear Information System (INIS)

    Fujimoto, Kenzo

    1995-01-01

    We are now living in the radiation environment modified by our technology. It is usually called 'Technologically Enhanced Natural Radiation' and have been discussed in the UNSCEAR Reports as an important source of exposure. The terrestrial radionuclide concentrations as well as the intensity of cosmic rays are considered to have been constant after our ancestors came down from trees and started walking on their two feet. However, we have been changing our environment to be more comfortable for our life and consequently ambient radiation levels are nomore what used to be. In this paper exposures due to natural radiation modified by our following activities are discussed: housing, balneology, cave excursion, mountain climbing, skiing, swimming, smoking and usage of mineral water, well water, coal, natural gas, phosphate rocks and minerals. In the ICRP Publication No. 39, it is clearly mentioned that even natural radiation should be controlled as far as it is controllable. We have to pay more attention to our activities not to enhance the exposure due to unnecessary, avoidable radiation. (author)

  9. Biomonitoring Human Exposure to Household Air Pollution and Association with Self-reported Health Symptoms – A Stove Intervention Study in Peru

    Science.gov (United States)

    Li, Zheng; Commodore, Adwoa; Hartinger, Stella; Lewin, Michael; Sjödin, Andreas; Pittman, Erin; Trinidad, Debra; Hubbard, Kendra; Lanata, Claudio F.; Gil, Ana I.; Mäusezahl, Daniel; Naeher, Luke P.

    2016-01-01

    Background Household air pollution (HAP) from indoor biomass stoves contains harmful pollutants, such as polycyclic aromatic hydrocarbons (PAHs), and is a leading risk factor for global disease burden. We used biomonitoring to assess HAP exposure and association with self-reported symptoms in 334 non-smoking Peruvian women to evaluate the efficacy of a stove intervention program. Methods We conducted a cross-sectional study within the framework of a community randomized control trial. Using urinary PAH metabolites (OH-PAHs) as the exposure biomarkers, we investigated whether the intervention group (n = 155, with new chimney-equipped stoves) were less exposed to HAP compared to the control group (n = 179, with mostly open-fire stoves). We also estimated associations between the exposure biomarkers, risk factors, and self-reported health symptoms, such as recent eye conditions, respiratory conditions, and headache. Results We observed reduced headache and ocular symptoms in the intervention group than the control group. Urinary 2-naphthol, a suggested biomarker for inhalation PAH exposure, was significantly lower in the intervention group (GM with 95% CI: 13.4 [12.3, 14.6] μg/g creatinine) compared to control group (16.5 [15.0, 18.0] μg/g creatinine). Stove type and/or 2-naphthol was associated with a number of self-reported symptoms, such as red eye (adjusted OR with 95% CI: 3.80 [1.32, 10.9]) in the past 48 h. Conclusions Even with the improved stoves, the biomarker concentrations in this study far exceeded those of the general populations and were higher than a no-observed-genotoxic-effect-level, indicating high exposure and a potential for increased cancer risk in the population. PMID:27680405

  10. Assessing human variability in kinetics for exposures to multiple environmental chemicals: a physiologically based pharmacokinetic modeling case study with dichloromethane, benzene, toluene, ethylbenzene, and m-xylene.

    Science.gov (United States)

    Valcke, Mathieu; Haddad, Sami

    2015-01-01

    The objective of this study was to compare the magnitude of interindividual variability in internal dose for inhalation exposure to single versus multiple chemicals. Physiologically based pharmacokinetic models for adults (AD), neonates (NEO), toddlers (TODD), and pregnant women (PW) were used to simulate inhalation exposure to "low" (RfC-like) or "high" (AEGL-like) air concentrations of benzene (Bz) or dichloromethane (DCM), along with various levels of toluene alone or toluene with ethylbenzene and xylene. Monte Carlo simulations were performed and distributions of relevant internal dose metrics of either Bz or DCM were computed. Area under the blood concentration of parent compound versus time curve (AUC)-based variability in AD, TODD, and PW rose for Bz when concomitant "low" exposure to mixtures of increasing complexities occurred (coefficient of variation (CV) = 16-24%, vs. 12-15% for Bz alone), but remained unchanged considering DCM. Conversely, AUC-based CV in NEO fell (15 to 5% for Bz; 12 to 6% for DCM). Comparable trends were observed considering production of metabolites (AMET), except for NEO's CYP2E1-mediated metabolites of Bz, where an increased CV was observed (20 to 71%). For "high" exposure scenarios, Cmax-based variability of Bz and DCM remained unchanged in AD and PW, but decreased in NEO (CV= 11-16% to 2-6%) and TODD (CV= 12-13% to 7-9%). Conversely, AMET-based variability for both substrates rose in every subpopulation. This study analyzed for the first time the impact of multiple exposures on interindividual variability in toxicokinetics. Evidence indicates that this impact depends upon chemical concentrations and biochemical properties, as well as the subpopulation and internal dose metrics considered.

  11. Pesticide Flow Analysis to Assess Human Exposure in Greenhouse Flower Production in Colombia

    Directory of Open Access Journals (Sweden)

    Claudia R. Binder

    2013-03-01

    Full Text Available Human exposure assessment tools represent a means for understanding human exposure to pesticides in agricultural activities and managing possible health risks. This paper presents a pesticide flow analysis modeling approach developed to assess human exposure to pesticide use in greenhouse flower crops in Colombia, focusing on dermal and inhalation exposure. This approach is based on the material flow analysis methodology. The transfer coefficients were obtained using the whole body dosimetry method for dermal exposure and the button personal inhalable aerosol sampler for inhalation exposure, using the tracer uranine as a pesticide surrogate. The case study was a greenhouse rose farm in the Bogota Plateau in Colombia. The approach was applied to estimate the exposure to pesticides such as mancozeb, carbendazim, propamocarb hydrochloride, fosetyl, carboxin, thiram, dimethomorph and mandipropamide. We found dermal absorption estimations close to the AOEL reference values for the pesticides carbendazim, mancozeb, thiram and mandipropamide during the study period. In addition, high values of dermal exposure were found on the forearms, hands, chest and legs of study participants, indicating weaknesses in the overlapping areas of the personal protective equipment parts. These results show how the material flow analysis methodology can be applied in the field of human exposure for early recognition of the dispersion of pesticides and support the development of measures to improve operational safety during pesticide management. Furthermore, the model makes it possible to identify the status quo of the health risk faced by workers in the study area.

  12. Risk exposures for human ornithosis in a poultry processing plant modified by use of personal protective equipment: an analytical outbreak study.

    Science.gov (United States)

    Williams, C J; Sillis, M; Fearne, V; Pezzoli, L; Beasley, G; Bracebridge, S; Reacher, M; Nair, P

    2013-09-01

    Ornithosis outbreaks in poultry processing plants are well-described, but evidence for preventive measures is currently lacking. This study describes a case-control study into an outbreak of ornithosis at a poultry processing plant in the East of England, identified following three employees being admitted to hospital. Workers at the affected plant were recruited via their employer, with exposures assessed using a self-completed questionnaire. Cases were ascertained using serological methods or direct antigen detection in sputum. 63/225 (28%) staff participated, with 10% of participants showing evidence of recent infection. Exposure to the killing/defeathering and automated evisceration areas, and contact with viscera or blood were the main risk factors for infection. Personal protective equipment (goggles and FFP3 masks) reduced the effect of exposure to risk areas and to self-contamination with potentially infectious material. Our study provides some evidence of effectiveness for respiratory protective equipment in poultry processing plants where there is a known and current risk of ornithosis. Further studies are required to confirm this tentative finding, but in the meantime respiratory protective equipment is recommended as a precautionary measure in plants where outbreaks of ornithosis occur.

  13. Weighing serological evidence of human exposure to animal influenza viruses − A literature review

    NARCIS (Netherlands)

    Sikkema, R.S. (Reina S.); G.S. Freidl (Gudrun); E.I. de Bruin (Esther); M.P.G. Koopmans D.V.M. (Marion)

    2016-01-01

    textabstractAssessing influenza A virus strains circulating in animals and their potential to cross the species barrier and cause human infections is important to improve human influenza surveillance and preparedness. We reviewed studies describing serological evidence of human exposure to animal

  14. Human Health Effects Associated with Exposure to Cyanobacteria and Cyanotoxins: What Do We Know?

    Science.gov (United States)

    The study of environmental health typically focuses on human populations. However, companion animals, livestock and wildlife also experience adverse health effects from environmental pollutants. Animals may experience direct exposure to pollutants unlike people in most ambient ex...

  15. Human population exposure to cosmic radiation

    International Nuclear Information System (INIS)

    Bouville, A.; Lowder, W.M.

    1988-01-01

    Critical evaluations of existing data on cosmic radiation in the atmosphere and in interplanetary space have been carried out in order to estimate the exposure of the world's population to this important component of natural background radiation. Data on population distribution and mean terrain heights on a 1 x 1 degree grid have been folded in to estimate regional and global dose distributions. The per caput annual dose equivalent at ground altitudes is estimated to be 270 μSv from charged particles and 50 μSv from neutrons. More than 100 million people receive more than 1 mSv in a year, and two million in excess of 5 mSv. Aircraft flight crews and frequent flyers receive an additional annual dose equivalent in the order of 1 mSv, though the global per caput annual dose equivalent from airplane flights is only about 1 μSv. Future space travellers on extended missions are likely to receive dose equivalents in the range 0.11 Sv, with the possibility of higher doses at relatively high dose rates from unusually large solar flares. These results indicate a critical need for a better understanding of the biological significance of chronic neutron and heavy charged particle exposure. (author)

  16. Exposure to Human Immunodeficiency Disease. What Precautions ...

    African Journals Online (AJOL)

    Background: The Human Immunodeficiency Virus (HIV) epidemic is more pronounced in sub-Saharan Africa. The ever-increasing prevalence of HIV infection and the continued improvement in clinical management has increased the likelihood of these patients being managed by healthcare workers. The aim of the review ...

  17. High Throughput Heuristics for Prioritizing Human Exposure to ...

    Science.gov (United States)

    The risk posed to human health by any of the thousands of untested anthropogenic chemicals in our environment is a function of both the potential hazard presented by the chemical, and the possibility of being exposed. Without the capacity to make quantitative, albeit uncertain, forecasts of exposure, the putative risk of adverse health effect from a chemical cannot be evaluated. We used Bayesian methodology to infer ranges of exposure intakes that are consistent with biomarkers of chemical exposures identified in urine samples from the U.S. population by the National Health and Nutrition Examination Survey (NHANES). We perform linear regression on inferred exposure for demographic subsets of NHANES demarked by age, gender, and weight using high throughput chemical descriptors gleaned from databases and chemical structure-based calculators. We find that five of these descriptors are capable of explaining roughly 50% of the variability across chemicals for all the demographic groups examined, including children aged 6-11. For the thousands of chemicals with no other source of information, this approach allows rapid and efficient prediction of average exposure intake of environmental chemicals. The methods described by this manuscript provide a highly improved methodology for HTS of human exposure to environmental chemicals. The manuscript includes a ranking of 7785 environmental chemicals with respect to potential human exposure, including most of the Tox21 in vit

  18. Human exposure to soil contaminants in subarctic Ontario, Canada

    Directory of Open Access Journals (Sweden)

    Ellen Stephanie Reyes

    2015-05-01

    Full Text Available Background: Chemical contaminants in the Canadian subarctic present a health risk with exposures primarily occurring via the food consumption. Objective: Characterization of soil contaminants is needed in northern Canada due to increased gardening and agricultural food security initiatives and the presence of known point sources of pollution. Design: A field study was conducted in the western James Bay Region of Ontario, Canada, to examine the concentrations of polychlorinated biphenyls, dichlorodiphenyltrichloroethane and its metabolites (ΣDDT, other organochlorines, and metals/metalloids in potentially contaminated agriculture sites. Methods: Exposure pathways were assessed by comparing the estimated daily intake to acceptable daily intake values. Ninety soil samples were collected at random (grid sampling from 3 plots (A, B, and C in Fort Albany (on the mainland, subarctic Ontario, Canada. The contaminated-soil samples were analysed by gas chromatography with an electron capture detector or inductively coupled plasma mass spectrometer. Results: The range of ΣDDT in 90 soil samples was below the limit of detection to 4.19 mg/kg. From the 3 soil plots analysed, Plot A had the highest ΣDDT mean concentration of 1.12 mg/kg, followed by Plot B and Plot C which had 0.09 and 0.01 mg/kg, respectively. Concentrations of other organic contaminants and metals in the soil samples were below the limit of detection or found in low concentrations in all plots and did not present a human health risk. Conclusions: Exposure analyses showed that the human risk was below regulatory thresholds. However, the ΣDDT concentration in Plot A exceeded soil guidelines set out by the Canadian Council of Ministers of the Environment of 0.7 mg/kg, and thus the land should not be used for agricultural or recreational purposes. Both Plots B and C were below threshold limits, and this land can be used for agricultural purposes.

  19. A margin-of-exposure approach to assessment of noncancer risks of dioxins based on human exposure and response data.

    Science.gov (United States)

    Aylward, Lesa L; Goodman, Julie E; Charnley, Gail; Rhomberg, Lorenz R

    2008-10-01

    Risk assessment of human environmental exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDFs) and other dioxin-like compounds is complicated by several factors, including limitations in measuring intakes because of the low concentrations of these compounds in foods and the environment and interspecies differences in pharmacokinetics and responses. We examined the feasibility of relying directly on human studies of exposure and potential responses to PCDD/PCDFs and related compounds in terms of measured lipid-adjusted concentrations to assess margin of exposure (MOE) in a quantitative, benchmark dose (BMD)-based framework using representative exposure and selected response data sets. We characterize estimated central tendency and upper-bound general U.S. population lipid-adjusted concentrations of PCDD/PCDFs from the 1970s and early 2000s based on available data sets. Estimates of benchmark concentrations for three example responses of interest (induction of cytochrome P4501A2 activity, dental anomalies, and neonatal thyroid hormone alterations) were derived based on selected human studies. The exposure data sets indicate that current serum lipid concentrations in young adults are approximately 6- to 7-fold lower than 1970s-era concentrations. Estimated MOEs for each end point based on current serum lipid concentrations range from 100 for dental anomalies-approximately 6-fold greater than would have existed during the 1970s. Human studies of dioxin exposure and outcomes can be used in a BMD framework for quantitative assessments of MOE. Incomplete exposure characterization can complicate the use of such studies in a BMD framework.

  20. Lack of Exposure in a First-in-Man Study Due to Aldehyde Oxidase Metabolism: Investigated by Use of 14C-microdose, Humanized Mice, Monkey Pharmacokinetics, and In Vitro Methods.

    Science.gov (United States)

    Jensen, Klaus Gjervig; Jacobsen, Anne-Marie; Bundgaard, Christoffer; Nilausen, Dorrit Østergaard; Thale, Zia; Chandrasena, Gamini; Jørgensen, Martin

    2017-01-01

    Inclusion of a microdose of 14 C-labeled drug in the first-in-man study of new investigational drugs and subsequent analysis by accelerator mass spectrometry has become an integrated part of drug development at Lundbeck. It has been found to be highly informative with regard to investigations of the routes and rates of excretion of the drug and the human metabolite profiles according to metabolites in safety testing guidance and also when additional metabolism-related issues needed to be addressed. In the first-in-man study with the NCE Lu AF09535, contrary to anticipated, surprisingly low exposure was observed when measuring the parent compound using conventional bioanalysis. Parallel accelerator mass spectrometry analysis revealed that the low exposure was almost exclusively attributable to extensive metabolism. The metabolism observed in humans was mediated via a human specific metabolic pathway, whereas an equivalent extent of metabolism was not observed in preclinical species. In vitro, incubation studies in human liver cytosol revealed involvement of aldehyde oxidase (AO) in the biotransformation of Lu AF09535. In vivo, substantially lower plasma exposure of Lu AF09535 was observed in chimeric mice with humanized livers compared with control animals. In addition, Lu AF09535 exhibited very low oral bioavailability in monkeys despite relatively low clearance after intravenous administration in contrast to the pharmacokinetics in rats and dogs, both showing low clearance and high bioavailability. The in vitro and in vivo methods applied were proved useful for identifying and evaluating AO-dependent metabolism. Different strategies to integrate these methods for prediction of in vivo human clearance of AO substrates were evaluated. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  1. The human milk study, HUMIS. Presentation of a birth cohort study which aims to collect milk samples from 6000 mothers, for the assessment of persistent organic pollutants (POPS), relating it to exposure factors and health outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Eggesboe, M.; Stigum, H.; Becher, G.; Magnus, P. [Norwegian Inst. of Public Health, Oslo (Norway); Polder, A.; Skaare, J.U. [The Norwegian School of Veterinay Science, Oslo (Norway); Lindstroem, G. [Orebro Univ., Orebro (Sweden)

    2004-09-15

    Although PCB has been forbidden for more than 20 years now, and its levels in human milk is declining, it remains among the chemicals in human milk causing most concern with regard to its possible detrimental effects on the fetus and the breastfed child. Due to our industry, amongst others, the Norwegian population has been rather heavily exposed to PCB. Furthermore, new environmental toxicants are steadily entering the scene, such as the Brominated flame retardants. The level of Brominated flame retardants in human milk has shown an exponential increase during the last ten years, and this group of chemicals, are causing increasingly more concern. Studies from Sweden has shown that the levels differ greatly between individuals, however, for reasons yet unknown. In Norway, the highest levels of Brominated flame retardants ever measured in the world was reported from fish in Mjoesa. Surprisingly few attempts has been made to identify dietary habits or other life style factors that are associated with the levels of these toxicants in human milk. Such knowledge is needed in order for accurate prophylactic measures to be taken by the population and of special importance to women before and during child bearing age, in order to keep the levels in human milk as low as possible. Furthermore, there is great need for more knowledge of the effects of these toxicants on child health. The need for more research in this field, especially the need for prospective exposure data and the need for interdisciplinary approaches has been specifically targeted. Therefore a research initiative was taken in Norway to establish a prospective birth cohort which aims to recruit 6000 mother/child pairs, in whom human milk samples are collected in infancy and information on health outcomes are collected throughout the child's first seven years of life. The aim of this presentation is to describe this project in more detail and to give some preliminary results.

  2. The Progression of Circadian Phase during Light Exposure in Animals and Humans

    NARCIS (Netherlands)

    Beersma, Domien G. M.; Comas, Marian; Hut, Roelof A.; Gordijn, Marijke C. M.; Rueger, Melanie; Daan, Serge

    Studies in humans and mice revealed that circadian phase shifting effects of light are larger at the beginning of a light exposure interval than during subsequent exposure. Little is known about the dynamics of this response reduction phenomenon. Here the authors propose a method to obtain

  3. Pilot study testing a European human biomonitoring framework for biomarkers of chemical exposure in children and their mothers: experiences in the UK.

    Science.gov (United States)

    Exley, Karen; Aerts, Dominique; Biot, Pierre; Casteleyn, Ludwine; Kolossa-Gehring, Marike; Schwedler, Gerda; Castaño, Argelia; Angerer, Jürgen; Koch, Holger M; Esteban, Marta; Schindler, Birgit K; Schoeters, Greet; Den Hond, Elly; Horvat, Milena; Bloemen, Louis; Knudsen, Lisbeth E; Joas, Reinhard; Joas, Anke; Sepai, Ovnair

    2015-10-01

    Exposure to a number of environmental chemicals in UK mothers and children has been assessed as part of the European biomonitoring pilot study, Demonstration of a Study to Coordinate and Perform Human Biomonitoring on a European Scale (DEMOCOPHES). For the European-funded project, 17 countries tested the biomonitoring guidelines and protocols developed by COPHES. The results from the pilot study in the UK are presented; 21 school children aged 6-11 years old and their mothers provided hair samples to measure mercury and urine samples, to measure cadmium, cotinine and several phthalate metabolites: mono(2-ethyl-5-hydroxyhexyl)phthalate (5OH-MEHP), mono(2-ethyl-5-oxo-hexyl)phthalate (5oxo-MEHP) and mono(2-ethylhexyl)phthalate (MEHP), mono-ethyl phthalate (MEP), mono-iso-butyl phthalate (MiBP), mono-benzyl phthalate (MBzP) and mono-n-butyl phthalate (MnBP). Questionnaire data was collected on environment, health and lifestyle. Mercury in hair was higher in children who reported frequent consumption of fish (geometric mean 0.35 μg/g) compared to those that ate fish less frequently (0.13 μg/g, p = 0.002). Cadmium accumulates with age as demonstrated by higher levels of urinary cadmium in the mothers (geometric mean 0.24 μg/L) than in the children(0.14 μg/L). None of the mothers reported being regular smokers, and this was evident with extremely low levels of cotinine measured (maximum value 3.6 μg/L in mothers, 2.4 μg/L in children). Very low levels of the phthalate metabolites were also measured in both mothers and children (geometric means in mothers: 5OH-MEHP 8.6 μg/L, 5oxo-MEHP 5.1 μg/L, MEHP 1.2 μg/L, MEP 26.8 μg/L, MiBP 17.0 μg/L, MBzP 1.6 μg/L and MnBP 13.5 μg/L; and in children: 5OH-MEHP 18.4 μg/L, 5oxo-MEHP 11.4 μg/L, MEHP 1.4 μg/L, MEP 14.3 μg/L, MiBP 25.8 μg/L, MBzP 3.5 μg/L and MnBP 22.6 μg/L). All measured biomarker levels were similar to or below population-based reference values published by the US National Health and Nutrition

  4. Human exposure to bisphenol A by biomonitoring: Methods, results and assessment of environmental exposures

    International Nuclear Information System (INIS)

    Dekant, Wolfgang; Voelkel, Wolfgang

    2008-01-01

    Human exposure to bisphenol A is controversially discussed. This review critically assesses methods for biomonitoring of bisphenol A exposures and reported concentrations of bisphenol A in blood and urine of non-occupationally ('environmentally') exposed humans. From the many methods published to assess bisphenol A concentrations in biological media, mass spectrometry-based methods are considered most appropriate due to high sensitivity, selectivity and precision. In human blood, based on the known toxicokinetics of bisphenol A in humans, the expected very low concentrations of bisphenol A due to rapid biotransformation and the very rapid excretion result in severe limitations in the use of reported blood levels of bisphenol A for exposure assessment. Due to the rapid and complete excretion of orally administered bisphenol A, urine samples are considered as the appropriate body fluid for bisphenol A exposure assessment. In urine samples from several cohorts, bisphenol A (as glucuronide) was present in average concentrations in the range of 1-3 μg/L suggesting that daily human exposure to bisphenol A is below 6 μg per person (< 0.1 μg/kg bw/day) for the majority of the population

  5. Developing human health exposure scenarios for petroleum substances under REACH

    Energy Technology Data Exchange (ETDEWEB)

    Carter, M.; De Wilde, P.; Maksimainen, K.; Margary, A.; Money, C.; Pizzella, G.; Svanehav, T.; Tsang, W.; Urbanus, J.; Rohde, A.

    2012-12-15

    This report describes the approaches that were adopted by CONCAWE to prepare the human exposure estimates in the chemical safety assessments of the REACH registration dossiers for petroleum substances based on all applicable regulatory guidance. Separate exposure estimates were developed for workers and for consumers and included inhalation and dermal routes. The complex nature of petroleum substances required various scientifically justified refinements of the regulatory guidance.

  6. Western Canada study on animal and human health effects associated with exposure to emissions from oil and natural gas field facilities

    International Nuclear Information System (INIS)

    2002-01-01

    A study was conducted to examine whether beef cattle exposed to emissions from oil and gas batteries and other field facility sites are at a greater risk of productivity failure and disease than cattle which are not exposed. The study examined beef cattle productivity; assessment of the immune function in beef cattle; assessment of wildlife reproduction and immune function; and, exposure monitoring. This study focused on the association between flaring and reproductive outcomes in beef herds. The association between herd location in high sulfur deposition areas and increased risk of reproductive failure was also evaluated. The study includes exposure markers for both sweet gas emissions and sour gas sources. Passive air and water pollution monitors measured volatile organic carbons such as benzene, toluene, ethylbenzene, and xylene. Water and air pollution monitoring was also conducted for other compounds including sulphur dioxide, hydrogen sulphide, particulate matter, and polycyclic aromatic hydrocarbons. Final analysis and assessment of the data should be complete by late 2003 with a report available for peer review at the beginning of 2004

  7. Perspectives for integrating human and environmental exposure assessments.

    Science.gov (United States)

    Ciffroy, P; Péry, A R R; Roth, N

    2016-10-15

    Integrated Risk Assessment (IRA) has been defined by the EU FP7 HEROIC Coordination action as "the mutual exploitation of Environmental Risk Assessment for Human Health Risk Assessment and vice versa in order to coherently and more efficiently characterize an overall risk to humans and the environment for better informing the risk analysis process" (Wilks et al., 2015). Since exposure assessment and hazard characterization are the pillars of risk assessment, integrating Environmental Exposure assessment (EEA) and Human Exposure assessment (HEA) is a major component of an IRA framework. EEA and HEA typically pursue different targets, protection goals and timeframe. However, human and wildlife species also share the same environment and they similarly inhale air and ingest water and food through often similar overlapping pathways of exposure. Fate models used in EEA and HEA to predict the chemicals distribution among physical and biological media are essentially based on common properties of chemicals, and internal concentration estimations are largely based on inter-species (i.e. biota-to-human) extrapolations. Also, both EEA and HEA are challenged by increasing scientific complexity and resources constraints. Altogether, these points create the need for a better exploitation of all currently existing data, experimental approaches and modeling tools and it is assumed that a more integrated approach of both EEA and HEA may be part of the solution. Based on the outcome of an Expert Workshop on Extrapolations in Integrated Exposure Assessment organized by the HEROIC project in January 2014, this paper identifies perspectives and recommendations to better harmonize and extrapolate exposure assessment data, models and methods between Human Health and Environmental Risk Assessments to support the further development and promotion of the concept of IRA. Ultimately, these recommendations may feed into guidance showing when and how to apply IRA in the regulatory decision

  8. Survival of human lymphocytes after exposure to densely ionizing radiations

    International Nuclear Information System (INIS)

    Madhvanath, U.; Raju, M.R.; Kelly, L.S.

    1976-01-01

    Interphase death of human blood lymphocytes cultured in vitro was studied after exposure to 60 Co gamma rays and to accelerated ions of 1 H, 4 He, 7 Li, 11 B, 12 C, 20 Ne, 40 Ar, and π - meson beam under aerobic conditions. Exposures were also conducted under hypoxic conditions with 60 Co gamma rays, 4 He, 7 Li, and 12 C ion beams. Time course of interphase death was followed for 6 days after irradiation. Percent survivals were determined by using the trypan blue exclusion method. Survival curves at 5 days postirradiation were exponential for all radiations studied. These observations indicate that the production of interphase death of lymphocytes by densely ionizing radiations follows a pattern similar to that observed with colony-forming mammalian cells. However, the reproductive capacity of the latter cells is impaired with maximum effectiveness at energy densities associated with 220 keV/μm for the beam conditions used in this investigation. The much lower energy densities required to kill a lymphocyte suggest that a sensitive structure other than DNA may be responsible for the production of lymphocyte death, perhaps the membranes. The calculated inactivation cross sections for high-LET radiations above 650 keV/μm yielded values larger than the actual cell dimensions. It appears that contributions from delta rays become appreciable in this system at these LET's

  9. A dermatotoxicokinetic model of human exposures to jet fuel.

    Science.gov (United States)

    Kim, David; Andersen, Melvin E; Nylander-French, Leena A

    2006-09-01

    Workers, both in the military and the commercial airline industry, are exposed to jet fuel by inhalation and dermal contact. We present a dermatotoxicokinetic (DTK) model that quantifies the absorption, distribution, and elimination of aromatic and aliphatic components of jet fuel following dermal exposures in humans. Kinetic data were obtained from 10 healthy volunteers following a single dose of JP-8 to the forearm over a surface area of 20 cm2. Blood samples were taken before exposure (t = 0 h), after exposure (t = 0.5 h), and every 0.5 h for up to 3.5 h postexposure. The DTK model that best fit the data included five compartments: (1) surface, (2) stratum corneum (SC), (3) viable epidermis, (4) blood, and (5) storage. The DTK model was used to predict blood concentrations of the components of JP-8 based on dermal-exposure measurements made in occupational-exposure settings in order to better understand the toxicokinetic behavior of these compounds. Monte Carlo simulations of dermal exposure and cumulative internal dose demonstrated no overlap among the low-, medium-, and high-exposure groups. The DTK model provides a quantitative understanding of the relationship between the mass of JP-8 components in the SC and the concentrations of each component in the systemic circulation. The model may be used for the development of a toxicokinetic modeling strategy for multiroute exposure to jet fuel.

  10. The involvement of oxidative stress in the mechanisms of damaging cadmium action in bone tissue: A study in a rat model of moderate and relatively high human exposure

    International Nuclear Information System (INIS)

    Brzoska, Malgorzata M.; Rogalska, Joanna; Kupraszewicz, Elzbieta

    2011-01-01

    It was investigated whether cadmium (Cd) may induce oxidative stress in the bone tissue in vivo and in this way contribute to skeleton damage. Total antioxidative status (TAS), antioxidative enzymes (glutathione peroxidase, superoxide dismutase, catalase), total oxidative status (TOS), hydrogen peroxide (H 2 O 2 ), lipid peroxides (LPO), total thiol groups (TSH) and protein carbonyl groups (PC) as well as Cd in the bone tissue at the distal femoral epiphysis and femoral diaphysis of the male rats that received drinking water containing 0, 5, or 50 mg Cd/l for 6 months were measured. Cd, depending on the level of exposure and bone location, decreased the bone antioxidative capacity and enhanced its oxidative status resulting in oxidative stress and oxidative protein and/or lipid modification. The treatment with 5 and 50 mg Cd/l decreased TAS and activities of antioxidative enzymes as well as increased TOS and concentrations of H 2 O 2 and PC at the distal femur. Moreover, at the higher exposure, the concentration of LPO increased and that of TSH decreased. The Cd-induced changes in the oxidative/antioxidative balance of the femoral diaphysis, abundant in cortical bone, were less advanced than at the distal femur, where trabecular bone predominates. The results provide evidence that, even moderate, exposure to Cd induces oxidative stress and oxidative modifications in the bone tissue. Numerous correlations noted between the indices of oxidative/antioxidative bone status, and Cd accumulation in the bone tissue as well as indices of bone turnover and bone mineral status, recently reported by us (Toxicology 2007, 237, 89-103) in these rats, allow for the hypothesis that oxidative stress is involved in the mechanisms of damaging Cd action in the skeleton. The paper is the first report from an in vivo study indicating that Cd may affect bone tissue through disorders in its oxidative/antioxidative balance resulting in oxidative stress.

  11. MANAGEMENT OF OCCUPATIONAL EXPOSURE TO THE HUMAN

    African Journals Online (AJOL)

    laboratory study that demonstrated that more blood is transferred by deeper ..... were routinely referred to the Nutritionist for advice on proper ... Ann Acc Med Singapore 1999; 28: 760. —767. 2. ...... intestinal bacteria, and its metabolism in the liver. Folic acid is ...... etiology by a number of studies4' 5 in Europe, India such as ...

  12. Indicative and complementary effects of human biological indicators for heavy metal exposure assessment.

    Science.gov (United States)

    Xing, Ruiya; Li, Yonghua; Zhang, Biao; Li, Hairong; Liao, Xiaoyong

    2017-10-01

    Although human biological indicators have been widely utilized for biomonitoring environmental pollutants in health exposure assessment, the relationship between internal and external exposure has not yet been adequately established. In this study, we collected and analyzed 61 rice, 56 pepper, and 58 soil samples, together with 107 hair, 107 blood, and 107 urine samples from residents living in selected intensive mining areas in China. Concentrations of most of the four elements considered (Pb, Cd, Hg, and Se) exceeded national standards, implying high exposure risk in the study areas. Regression analysis also revealed a correlation (0.33, P human hair (as well as in human blood); to some extent, Pb content in hair and blood could therefore be used to characterize external Pb exposure. The correlation between Hg in rice and in human hair (up to 0.5, P human hair for Hg exposure. A significant correlation was also noted between concentrations of some elements in different human samples, for example, between Hg in hair and blood (0.641, P assessing heavy metal exposure.

  13. Cadmium osteotoxicity in experimental animals: Mechanisms and relationship to human exposures

    International Nuclear Information System (INIS)

    Bhattacharyya, Maryka H.

    2009-01-01

    Extensive epidemiological studies have recently demonstrated increased cadmium exposure correlating significantly with decreased bone mineral density and increased fracture incidence in humans at lower exposure levels than ever before evaluated. Studies in experimental animals have addressed whether very low concentrations of dietary cadmium can negatively impact the skeleton. This overview evaluates results in experimental animals regarding mechanisms of action on bone and the application of these results to humans. Results demonstrate that long-term dietary exposures in rats, at levels corresponding to environmental exposures in humans, result in increased skeletal fragility and decreased mineral density. Cadmium-induced demineralization begins soon after exposure, within 24 h of an oral dose to mice. In bone culture systems, cadmium at low concentrations acts directly on bone cells to cause both decreases in bone formation and increases in bone resorption, independent of its effects on kidney, intestine, or circulating hormone concentrations. Results from gene expression microarray and gene knock-out mouse models provide insight into mechanisms by which cadmium may affect bone. Application of the results to humans is considered with respect to cigarette smoke exposure pathways and direct vs. indirect effects of cadmium. Clearly, understanding the mechanism(s) by which cadmium causes bone loss in experimental animals will provide insight into its diverse effects in humans. Preventing bone loss is critical to maintaining an active, independent lifestyle, particularly among elderly persons. Identifying environmental factors such as cadmium that contribute to increased fractures in humans is an important undertaking and a first step to prevention.

  14. Integrating population dynamics into mapping human exposure to seismic hazard

    Directory of Open Access Journals (Sweden)

    S. Freire

    2012-11-01

    Full Text Available Disaster risk is not fully characterized without taking into account vulnerability and population exposure. Assessment of earthquake risk in urban areas would benefit from considering the variation of population distribution at more detailed spatial and temporal scales, and from a more explicit integration of this improved demographic data with existing seismic hazard maps. In the present work, "intelligent" dasymetric mapping is used to model population dynamics at high spatial resolution in order to benefit the analysis of spatio-temporal exposure to earthquake hazard in a metropolitan area. These night- and daytime-specific population densities are then classified and combined with seismic intensity levels to derive new spatially-explicit four-class-composite maps of human exposure. The presented approach enables a more thorough assessment of population exposure to earthquake hazard. Results show that there are significantly more people potentially at risk in the daytime period, demonstrating the shifting nature of population exposure in the daily cycle and the need to move beyond conventional residence-based demographic data sources to improve risk analyses. The proposed fine-scale maps of human exposure to seismic intensity are mainly aimed at benefiting visualization and communication of earthquake risk, but can be valuable in all phases of the disaster management process where knowledge of population densities is relevant for decision-making.

  15. Human exposure to cyanotoxins and their effects on health.

    Science.gov (United States)

    Drobac, Damjana; Tokodi, Nada; Simeunović, Jelica; Baltić, Vladimir; Stanić, Dina; Svirčev, Zorica

    2013-06-01

    Cyanotoxins are secondary metabolites produced by cyanobacteria. They pose a threat to human health and the environment. This review summarises the existing data on human exposure to cyanotoxins through drinking water, recreational activities (e.g., swimming, canoeing or bathing), the aquatic food web, terrestrial plants, food supplements, and haemodialysis. Furthermore, it discusses the tolerable daily intake and guideline values for cyanotoxins (especially microcystins) as well as the need to implement risk management measures via national and international legislation.

  16. Multi-scale spatial modeling of human exposure from local sources to global intake

    DEFF Research Database (Denmark)

    Wannaz, Cedric; Fantke, Peter; Jolliet, Olivier

    2018-01-01

    Exposure studies, used in human health risk and impact assessments of chemicals are largely performed locally or regionally. It is usually not known how global impacts resulting from exposure to point source emissions compare to local impacts. To address this problem, we introduce Pangea......, an innovative multi-scale, spatial multimedia fate and exposure assessment model. We study local to global population exposure associated with emissions from 126 point sources matching locations of waste-to-energy plants across France. Results for three chemicals with distinct physicochemical properties...... occur within a 100 km radius from the source. This suggests that, by neglecting distant low-level exposure, local assessments might only account for fractions of global cumulative intakes. We also study ~10,000 emission locations covering France more densely to determine per chemical and exposure route...

  17. Wildfire smoke exposure and human health: Significant gaps in research for a growing public health issue.

    Science.gov (United States)

    Black, Carolyn; Tesfaigzi, Yohannes; Bassein, Jed A; Miller, Lisa A

    2017-10-01

    Understanding the effect of wildfire smoke exposure on human health represents a unique interdisciplinary challenge to the scientific community. Population health studies indicate that wildfire smoke is a risk to human health and increases the healthcare burden of smoke-impacted areas. However, wildfire smoke composition is complex and dynamic, making characterization and modeling difficult. Furthermore, current efforts to study the effect of wildfire smoke are limited by availability of air quality measures and inconsistent air quality reporting among researchers. To help address these issues, we conducted a substantive review of wildfire smoke effects on population health, wildfire smoke exposure in occupational health, and experimental wood smoke exposure. Our goal was to evaluate the current literature on wildfire smoke and highlight important gaps in research. In particular we emphasize long-term health effects of wildfire smoke, recovery following wildfire smoke exposure, and health consequences of exposure in children. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Nutrition: assessment of human exposure to environment

    International Nuclear Information System (INIS)

    Zaini Hamzah; Zuraidah Abdullah Munir; Suziana Ismail; Abd Khalik Wood; Suhaimi Hamzah; Syamsiah Abdul Rahman; Wee Boon Siong; Suhaimi Alias; Nazatul Ashita Abdullah Salim

    2004-01-01

    The objectives of the research are (I) to determine the essential and toxic elements in foodstuffs, (II) to study the sufficient elemental levels in foodstuff for the dietary intake, (III) to assess the relationship of the essential and toxic elements intake to the types of diet and (IV) to compare the food quality of Malaysian various cuisine on essential and toxic elements

  19. Assessing Sources of Human Methylmercury Exposure Using Stable Mercury Isotopes

    DEFF Research Database (Denmark)

    Li, Miling; Sherman, Laura S; Blum, Joel D

    2014-01-01

    Seafood consumption is the primary route of methylmercury (MeHg) exposure for most populations. Inherent uncertainties in dietary survey data point to the need for an empirical tool to confirm exposure sources. We therefore explore the utility of Hg stable isotope ratios in human hair as a new...... method for discerning MeHg exposure sources. We characterized Hg isotope fractionation between humans and their diets using hair samples from Faroese whalers exposed to MeHg predominantly from pilot whales. We observed an increase of 1.75‰ in δ(202)Hg values between pilot whale muscle tissue and Faroese...... whalers' hair but no mass-independent fractionation. We found a similar offset in δ(202)Hg between consumed seafood and hair samples from Gulf of Mexico recreational anglers who are exposed to lower levels of MeHg from a variety of seafood sources. An isotope mixing model was used to estimate individual...

  20. The causes and consequences of human exposure to ionising radiation

    International Nuclear Information System (INIS)

    Clarke, R.H.

    1991-01-01

    Few phenomena cause as much concern in developed countries as human exposure to artificial sources of radiation, and yet there are more potent threats to health: natural radiation is more pervasive and exposures more substantial; common practices such as smoking and drinking are more detrimental. Developing countries may be more anxious to establish radiological procedures than radiological protection. This paper gives the ranges of exposure to which people are subjected from natural and artificial sources which should help to put all doses in perspective. The relationship between dose and risk is established and used to show that exposures to radiation leak to low levels of risk. Finally, the new recommendations of ICRP for the control of radiation risk are presented. (Author)

  1. Traditional goat husbandry may substantially contribute to human toxoplasmosis exposure

    Science.gov (United States)

    Raising goats in settings that are highly contaminated with oocysts of Toxoplasma gondii may contribute significantly to human exposure to this zoonotic parasite. Increasing consumption of young goats in Romania, where goats are typically reared in backyards that are also home to cats (the definitiv...

  2. Spatial Analysis of Human Exposure and Vulnerability to Coastal ...

    African Journals Online (AJOL)

    Disasters in coastal cities have shown an ever-increasing frequency of occurrence. Population growth and urbanisation have increased the vulnerability of properties and societies in coastal flood-prone areas. Analysis of human exposure and vulnerability is one of the main strategies used to determine the necessary ...

  3. Radiation exposure and radiation hazards of human population. Pt. 1

    International Nuclear Information System (INIS)

    Jacobi, W.

    1982-01-01

    The present Part I provides a survey on the various sources of natural and artificial radiation exposure of human population. Furthermore, biological radiation effects and radiation damages are surveyed. In an appendix, radiation types, radiation doses, and radiation dose units are explained. (orig./GSCH) [de

  4. Human health risk assessment related to cyanotoxins exposure.

    Science.gov (United States)

    Funari, Enzo; Testai, Emanuela

    2008-01-01

    This review focuses on the risk assessment associated with human exposure to cyanotoxins, secondary metabolites of an ubiquitous group of photosynthetic procariota. Cyanobacteria occur especially in eutrophic inland and coastal surface waters, where under favorable conditions they attain high densities and may form blooms and scums. Cyanotoxins can be grouped according to their biological effects into hepatotoxins, neurotoxins, cytotoxins, and toxins with irritating potential, also acting on the gastrointestinal system. The chemical and toxicological properties of the main cyanotoxins, relevant for the evaluation of possible risks for human health, are presented. Humans may be exposed to cyanotoxins via several routes, with the oral one being by far the most important, occurring by ingesting contaminated drinking water, food, some dietary supplements, or water during recreational activities. Acute and short-term toxic effects have been associated in humans with exposure to high levels of cyanotoxins in drinking and bathing waters. However, the chronic exposure to low cyanotoxin levels remains a critical issue. This article identifies the actual risky exposure scenarios, provides toxicologically derived reference values, and discusses open issues and research needs.

  5. Biocides Steering Group on human exposure assessment: A preliminary report

    NARCIS (Netherlands)

    Hemmen, J.J. van

    1999-01-01

    In a project granted by DG XI of the European Commission, it is attempted to collate experimental and theoretical data on human (workers and consumers) exposure assessment to biocidal products, and to outline the methodology for sampling and measurement. On the basis of the available evidence,

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

    DEFF Research Database (Denmark)

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

    2008-01-01

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

  7. COMPARING THE UTILITY OF MULTIMEDIA MODELS FOR HUMAN AND ECOLOGICAL EXPOSURE ANALYSIS: TWO CASES

    Science.gov (United States)

    A number of models are available for exposure assessment; however, few are used as tools for both human and ecosystem risks. This discussion will consider two modeling frameworks that have recently been used to support human and ecological decision making. The study will compare ...

  8. Biomonitoring human exposure to environmental carcinogenic chemicals

    DEFF Research Database (Denmark)

    Farmer, P.B.; Sepai, O.; Lawrence, R.

    1996-01-01

    A coordinated study was carried out on the development, evaluation and application of biomonitoring procedures for populations exposed to environmental genotoxic pollutants. The procedures used involved both direct measurement of DNA or protein damage (adducts) and assessment of second biological...... spectrometry). The measurement of adducts was focused on those from genotoxicants that result from petrochemical combustion or processing, e.g. low-molecular-weight alkylating agents, PAHs and compounds that cause oxidative DNA damage. Cytogenetic analysis of lymphocytes was undertaken (micronuclei, chromosome...... aberrations and sister chromatid exchanges) and mutation frequency was estimated at a number of loci including the hprt gene and genes involving in cancer development. Blood and urine samples from individuals exposed to urban pollution were collected. Populations exposed through occupational or medical...

  9. A systematic review of the human body burden of e-waste exposure in China.

    Science.gov (United States)

    Song, Qingbin; Li, Jinhui

    2014-07-01

    As China is one of the countries facing the most serious pollution and human exposure effects of e-waste in the world, much of the population there is exposed to potentially hazardous substances due to informal e-waste recycling processes. This report reviews recent studies on human exposure to e-waste in China, with particular focus on exposure routes (e.g. dietary intake, inhalation, and soil/dust ingestion) and human body burden markers (e.g. placenta, umbilical cord blood, breast milk, blood, hair, and urine) and assesses the evidence for the association between such e-waste exposure and the human body burden in China. The results suggest that residents in the e-waste exposure areas, located mainly in the three traditional e-waste recycling sites (Taizhou, Guiyu, and Qingyuan), are faced with a potential higher daily intake of these pollutants than residents in the control areas, especially via food ingestion. Moreover, pollutants (PBBs, PBDEs, PCBs, PCDD/Fs, and heavy metals) from the e-waste recycling processes were all detectable in the tissue samples at high levels, showing that they had entered residents' bodies through the environment and dietary exposure. Children and neonates are the groups most sensitive to the human body effects of e-waste exposure. We also recorded plausible outcomes associated with exposure to e-waste, including 7 types of human body burden. Although the data suggest that exposure to e-waste is harmful to health, better designed epidemiological investigations in vulnerable populations, especially neonates and children, are needed to confirm these associations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Human exposure to polybrominated diphenyl ethers at production area, China.

    Science.gov (United States)

    Jin, Jun; Wang, Ying; Yang, Congqiao; Hu, Jicheng; Liu, Weizhi; Cui, Jian

    2010-05-01

    The concentrations of polybrominated diphenyl ethers (PBDEs) were detected in air and aquatic products in PBDEs production areas which are located at the south coast area of Laizhou Bay, Shandong province, China in this study. Concentrations of SigmaPBDEs in the air ranged from 0.47 ng/m3 to 161 ng/m3. In aquatic products, concentrations of SigmaPBDEs ranged from 2.7 ng/g wet weight to 42 ng/g wet weight. The mean dietary intake of SigmaPBDEs via aquatic products consumption in this study was 218 ng/day. Daily intake of SigmaPBDEs via inhalation in this study was 612 ng for men and 455 ng for women. With a contribution of 80%, BDE-209 was predominant in the total intake. Dietary intake and breathing inhalation contributed 29 and 71%, respectively, to the total PBDEs intake. The results indicate that breathing inhalation also plays a very significant pathway for the population of the PBDEs production area. Compared with similar studies in other countries, human exposure to PBDEs via diet and inhalation in this study was the highest in the world. Copyright (c) 2010 SETAC.

  11. Quantitative analysis of untreated human nails for monitoring human exposure to heavy metals

    International Nuclear Information System (INIS)

    Sera, Koichiro; Futatsugawa, Shouji; Murao, Satoshi; Clemente, E.

    2002-01-01

    In order to address global environmental issues, a standard-free method developed by ourselves has been successfully applied to various kinds of bio-samples. Especially, a method for untreated hairs has been applied in many polluted areas to study human exposure to toxic elements. In addition to hair, nail is expected to give us valuable information about human exposure to toxic elements. However, the analysis requires relatively large amounts of samples and laborious sample preparation techniques which necessitate internal standards. In this work, we have developed a quantitative method for untreated human-nail analysis based on the standard-free method. It requires neither large amounts of nails nor complicated target preparation procedure. Furthermore, it is perfectly free from any ambiguity in target preparation such as volatilization of certain elements and contamination of the sample during chemical ashing. The optimum conditions of irradiating nail samples are established, and accuracy and reproducibility of the present method are confirmed. It is found that ultrasonic washing in distilled water is effective for many nail samples preventing the loss of elements from the sample. It is also found that elemental concentration in nails strongly depends on their sampling positions. (author)

  12. ASSESSING CHILDREN'S EXPOSURES TO PESTICIDES: AN IMPORTANT APPLICATION OF THE STOCHASTIC HUMAN EXPOSURE AND DOSE SIMULATION MODEL (SHEDS)

    Science.gov (United States)

    Accurately quantifying human exposures and doses of various populations to environmental pollutants is critical for the Agency to assess and manage human health risks. For example, the Food Quality Protection Act of 1996 (FQPA) requires EPA to consider aggregate human exposure ...

  13. Human exposure to piroplasms in Central and Northern Italy

    Directory of Open Access Journals (Sweden)

    Simona Gabrielli

    2014-03-01

    Full Text Available A serosurvey has been conducted in Northern and Central Italy to investigate the presence in humans of antibodies against zoonotic Babesia and Theileria species. The study focused on a total of 432 volunteers, of which 290 were persistently exposed to tick bites because of their jobs (forester employees, livestock keepers, veterinary practitioners, farmers and hunters and 142 resident in the same area less frequently exposed. An indirect fluorescent antibody test (IFAT for humans was used to detect antibodies to Babesia microti, IFAT tests for veterinary use were modified to detect reactivity to Babesia bovis, Babesia canis and Theileria equi. A laboratory-derived ELISA was employed to detect antibodies to Babesia divergens. Both reactive and 10 negative sera were analysed against plasmodial antigens to evaluate possible aspecificity. A high reactivity to piroplasm antigens was found, showing significant difference between the sera of the two groups of volunteers (24% vs 7.0%; p<0.001. No cross-reactivity was observed, while each professional group showed reactivity that would fit with the professional risk exposure. In particular, a high reactivity to B. microti and B. divergens antigens was observed in foresters and hunters (32% and 12%, respectively. This is the first report on the human seroreactivity to piroplasms in Italy; it also provides additional epidemiological information on these tick-borne zoonoses in Europe. Our findings suggest the possible occurrence of piroplasm infections in Italy and alert physicians to consider these otherwise neglected parasitic diseases when dealing with any febrile illness, especially in subjects exposed to tick bites.

  14. Investigating Intergenerational Differences in Human PCB Exposure due to Variable Emissions and Reproductive Behaviors

    Science.gov (United States)

    Quinn, Cristina L.; Wania, Frank; Czub, Gertje; Breivik, Knut

    2011-01-01

    Background Reproductive behaviors—such as age of childbearing, parity, and breast-feeding prevalence—have changed over the same historical time period as emissions of polychlorinated biphenyls (PCB) and may produce intergenerational differences in human PCB exposure. Objectives Our goal in this study was to estimate prenatal, postnatal, and lifetime PCB exposures for women at different ages according to year of birth, and to evaluate the impact of reproductive characteristics on intergenerational differences in exposure. Methods We used the time-variant mechanistic model CoZMoMAN to calculate human bioaccumulation of PCBs, assuming both hypothetical constant and realistic time-variant emissions. Results Although exposure primarily depends on when an individual was born relative to the emission history of PCBs, reproductive behaviors can have a significant impact. Our model suggests that a mother’s reproductive history has a greater influence on the prenatal and postnatal exposures of her children than it does on her own cumulative lifetime exposure. In particular, a child’s birth order appears to have a strong influence on their prenatal exposure, whereas postnatal exposure is determined by the type of milk (formula or breast milk) fed to the infant. Conclusions Prenatal PCB exposure appears to be delayed relative to the time of PCB emissions, particularly among those born after the PCB production phaseout. Consequently, the health repercussions of environmental PCBs can be expected to persist for several decades, despite bans on their production for > 40 years. PMID:21156396

  15. Human Physiological Responses to Acute and Chronic Cold Exposure

    Science.gov (United States)

    Stocks, Jodie M.; Taylor, Nigel A. S.; Tipton, Michael J.; Greenleaf, John E.

    2001-01-01

    When inadequately protected humans are exposed to acute cold, excessive body heat is lost to the environment and unless heat production is increased and heat loss attenuated, body temperature will decrease. The primary physiological responses to counter the reduction in body temperature include marked cutaneous vasoconstriction and increased metabolism. These responses, and the hazards associated with such exposure, are mediated by a number of factors which contribute to heat production and loss. These include the severity and duration of the cold stimulus; exercise intensity; the magnitude of the metabolic response; and individual characteristics such as body composition, age, and gender. Chronic exposure to a cold environment, both natural and artificial, results in physiological alterations leading to adaptation. Three quite different, but not necessarily exclusive, patterns of human cold adaptation have been reported: metabolic, hypothermic, and insulative. Cold adaptation has also been associated with an habituation response, in which there is a desensitization, or damping, of the normal response to a cold stress. This review provides a comprehensive analysis of the human physiological and pathological responses to cold exposure. Particular attention is directed to the factors contributing to heat production and heat loss during acute cold stress, and the ability of humans to adapt to cold environments.

  16. Reconstruction of human exposure to heavy metals using synchrotron radiation microbeams in prehistoric and modern humans

    International Nuclear Information System (INIS)

    Koizumi, Akio; Azechi, Miki; Shirasawa, Koyo

    2009-01-01

    Teeth can serve as records of environmental exposure to heavy metals during their formation. We applied a new technology - synchrotron radiation microbeams (SRXRF) - for analysis of heavy metals in human permanent teeth in modern and historical samples. Each tooth was cut in half. A longitudinal section 200 μm in thickness was subjected to the determination of the heavy metal content by SRXRF or conventional analytical methods (ICP-MS analysis or reduction-aeration atomic absorption spectrometry). The relative concentrations of Pb, Hg, Cu and Zn measured by SRXRF were translated in concentrations (in g of heavy metal/g of enamel) using calibration curves by the two analytical methods. Concentrations in teeth in the modern females (n=5) were 1.2±0.5 μg/g (n=5) for Pb; 1.7±0.2 ng/g for Hg; 0.9±1.1 μg/g for Cu; 150±24.6 μg/g for Zn. The levels of Pb were highest in the teeth samples obtained from the humans of the Edo era (1603-1868 AD) (0.5-4.0 μg/g, n=4). No trend was observed in this study in the Hg content in teeth during 3,000 years. The concentrations of Cu were highest in teeth of two medieval craftsmen (57.0 and 220 μg/g). The levels of Zn were higher in modern subjects (P<0.05) than those in the Jomon (∼1000 BC) to Edo periods [113.2±27.4 (μg/g, n=11)]. Reconstruction of developmental exposure history to lead in a famous court painter of the Edo period (18th century) revealed high levels of Pb (7.1-22.0 μg/g) in his childhood. SRXRF is useful a method for reconstructing human exposures in very long trends. (author)

  17. Climate change impacts on human exposures to air pollution ...

    Science.gov (United States)

    This is an abstract for a presentations at the Annual Conference of the International Society on Exposure Science and Environmental Epidemiology. This presentation will serve as an introduction to the symposium. As we consider the potential health impacts of a warming planet, the relationships between climate change and air pollutants become increasingly important to understand. These relationships are complex and highly variable, causing a variety of environmental impacts at local, regional and global scales. Human exposures and health impacts for air pollutants have the potential to be altered by changes in climate through multiple factors that drive population exposures to these pollutants. Research on this topic will provide both state and local governments with the tools and scientific knowledge base to undertake any necessary adaptation of the air pollution regulations and/or public health management systems in the face of climate change.

  18. Using exposure prediction tools to link exposure and dosimetry for risk based decisions: a case study with phthalates

    Science.gov (United States)

    The Population Life-course Exposure to Health Effects Modeling (PLETHEM) platform being developed provides a tool that links results from emerging toxicity testing tools to exposure estimates for humans as defined by the USEPA. A reverse dosimetry case study using phthalates was ...

  19. Hair-to-blood ratio and biological half-life of mercury: experimental study of methylmercury exposure through fish consumption in humans.

    Science.gov (United States)

    Yaginuma-Sakurai, Kozue; Murata, Katsuyuki; Iwai-Shimada, Miyuki; Nakai, Kunihiko; Kurokawa, Naoyuki; Tatsuta, Nozomi; Satoh, Hiroshi

    2012-02-01

    The hair-to-blood ratio and biological half-life of methylmercury in a one-compartment model seem to differ between past and recent studies. To reevaluate them, 27 healthy volunteers were exposed to methylmercury at the provisional tolerable weekly intake (3.4 µg/kg body weight/week) for adults through fish consumption for 14 weeks, followed by a 15-week washout period after the cessation of exposure. Blood was collected every 1 or 2 weeks, and hair was cut every 4 weeks. Total mercury (T-Hg) concentrations were analyzed in blood and hair. The T-Hg levels of blood and hair changed with time (p < 0.001). The mean concentrations increased from 6.7 ng/g at week 0 to 26.9 ng/g at week 14 in blood, and from 2.3 to 8.8 µg/g in hair. The mean hair-to-blood ratio after the adjustment for the time lag from blood to hair was 344 ± 54 (S.D.) for the entire period. The half-lives of T-Hg were calculated from raw data to be 94 ± 23 days for blood and 102 ± 31 days for hair, but the half-lives recalculated after subtracting the background levels from the raw data were 57 ± 18 and 64 ± 22 days, respectively. In conclusion, the hair-to-blood ratio of methylmercury, based on past studies, appears to be underestimated in light of recent studies. The crude half-life may be preferred rather than the recalculated one because of the practicability and uncertainties of the background level, though the latter half-life may approximate the conventional one.

  20. Assessment of genetic risk for human exposure to radiation

    International Nuclear Information System (INIS)

    Sevcenko, V.A.; Rubanovic, A.V.

    2002-01-01

    Full text: The methodology of assessing the genetic risk of radiation exposure is based on the concept of 'hitting the target' in development of which N.V. Timofeeff-Ressovsky has played and important role. To predict genetic risk posed by irradiation, the U N Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has worked out direct and indirect methods of assessment, extrapolation, integral and palpitation criteria of risk analysis that together permit calculating the risk from human exposure on the basis of data obtained for mice. Based on the reports of UNSCEAR for the period from 1958 to 2001 the paper presents a retrospective analysis of the use of direct methods and the doubling dose method for quantitative determination of the genetic risk of human exposure expressed as different hereditary diseases. As early as 1962 UNSCEAR estimated the doubling dose (a dose causing as many mutations as those occurring spontaneously during one generation) at 1 Gy for cases of exposure to ionizing radiations with low LET at a low dose rate and this value was confirmed in the next UNSCEAR reports up to now. For cases of acute irradiation the doubling dose was estimated at 0,3-0,4 Gy for the period under review. The paper considers the evolution of the concepts of human natural hereditary variability which is a basis for assessing the risk of exposure by the doubling dose method. The level of human natural genetic variability per 1 000 000 newborns is estimated at 738 000 hereditary diseases including mendelian, chromosomal and multifactorial ones. The greatest difficulties in assessing the doubling dose value were found to occur in the case of multifactorial diseases the pheno typical expression of which depends on mutational events in polygenic systems and on numerous environmental factors. The introduction in calculations of the potential recoverability correction factor (RPCF) made it possible to assess the genetic risk taking into account this class of

  1. Assessment of the potential human health risks from exposure to complex substances in accordance with REACH requirements. "White spirit" as a case study.

    Science.gov (United States)

    McKee, Richard H; Tibaldi, Rosalie; Adenuga, Moyinoluwa D; Carrillo, Juan-Carlos; Margary, Alison

    2018-02-01

    The European chemical control regulation (REACH) requires that data on physical/chemical, toxicological and environmental hazards be compiled. Additionally, REACH requires formal assessments to ensure that substances can be safely used for their intended purposes. For health hazard assessments, reference values (Derived No Effect levels, DNELs) are calculated from toxicology data and compared to estimated exposure levels. If the ratio of the predicted exposure level to the DNEL, i.e. the Risk Characterization Ratio (RCR), is less than 1, the risk is considered controlled; otherwise, additional Risk Management Measures (RMM) must be applied. These requirements pose particular challenges for complex substances. Herein, "white spirit", a complex hydrocarbon solvent, is used as an example to illustrate how these procedures were applied. Hydrocarbon solvents were divided into categories of similar substances. Representative substances were identified for DNEL determinations. Adjustment factors were applied to the no effect levels to calculate the DNELs. Exposure assessments utilized a standardized set of generic exposure scenarios (GES) which incorporated exposure predictions for solvent handling activities. Computer-based tools were developed to automate RCR calculations and identify appropriate RMMs, allowing consistent communications to users via safety data sheets. Copyright © 2017 ExxonMobil Biomedical Sciences Inc. Published by Elsevier Inc. All rights reserved.

  2. Biomonitoring of the mycotoxin Zearalenone: current state-of-the art and application to human exposure assessment.

    Science.gov (United States)

    Mally, Angela; Solfrizzo, Michele; Degen, Gisela H

    2016-06-01

    Zearalenone (ZEN), a mycotoxin with high estrogenic activity in vitro and in vivo, is a widespread food contaminant that is commonly detected in maize, wheat, barley, sorghum, rye and other grains. Human exposure estimates based on analytical data on ZEN occurrence in various food categories and food consumption data suggest that human exposure to ZEN and modified forms of ZEN may be close to or even exceed the tolerable daily intake (TDI) derived by the European Food Safety Authority (EFSA) for some consumer groups. Considering the inherent uncertainties in estimating dietary intake of ZEN that may lead to an under- or overestimation of ZEN exposure and consequently human risk and current lack of data on vulnerable consumer groups, there is a clear need for more comprehensive and reliable exposure data to refine ZEN risk assessment. Human biomonitoring (HBM) is increasingly being recognized as an efficient and cost-effective way of assessing human exposure to food contaminants, including mycotoxins. Based on animal and (limited) human data on the toxicokinetics of ZEN, it appears that excretion of ZEN and its major metabolites may present suitable biomarkers of ZEN exposure. In view of the limitations of available dietary exposure data on ZEN and its modified forms, the purpose of this review is to provide an overview of recent studies utilizing HBM to monitor and assess human exposure to ZEN. Considerations are given to animal and human toxicokinetic data relevant to HBM, analytical methods, and available HBM data on urinary biomarkers of ZEN exposure in different cohorts.

  3. Ecological and human exposure assessment to PBDEs in Adige River.

    Science.gov (United States)

    Giulivo, Monica; Suciu, Nicoleta Alina; Eljarrat, Ethel; Gatti, Marina; Capri, Ettore; Barcelo, Damia

    2018-07-01

    The interest for environmental issues and the concern resulting from the potential exposure to contaminants were the starting point to develop methodologies in order to evaluate the consequences that those might have over both the environment and human health. Considering the feature of POPs, including PBDEs, such as bioaccumulation, biomagnification, long-range transport and adverse effects even long time after exposure, risk assessment of POPs requires specific approaches and tools. In this particular context, the MERLIN-Expo tool was used to assess the aquatic environmental exposure of Adige River to PBDEs and the accumulation of PBDEs in humans through the consumption of possible contaminated local aquatic food. The aquatic food web models provided as output of the deterministic simulation the time trend of concentrations for twenty years of BDE-47 and total PBDEs, expressed using the physico-chemical properties of BDE-47, in aquatic organisms of the food web of Adige River. For BDE-47, the highest accumulated concentrations were detected for two benthic species: Thymallus thymallus and Squalius cephalus whereas the lowest concentrations were obtained for the pelagic specie Salmo trutta marmoratus. The trend obtained for the total PBDEs, calculated using the physico-chemical properties of BDE-47, follows the one of BDE-47. For human exposure, different BDE-47 and total PBDEs concentration trends between children, adolescent, adults and elderly were observed, probably correlated with the human intake of fish products in the daily diet and the ability to metabolize these contaminants. In detail, for the adolescents, adults and elderly a continuous accumulation of the target contaminants during the simulation's years was observed, whereas for children a plateau at the end of the simulation period was perceived. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Human exposure to static magnetic fields and basic precautions

    International Nuclear Information System (INIS)

    Vulevic, B.

    1999-01-01

    The development of new technologies using the static magnetic fields and their application in the last several years has increased the possibility of higher human exposure to such fields what has raised an issue of potential adverse health effects. The object of this work is to point, on the basis of the past knowledge, to the significance of the problem and therefore to contribute to its popularization. (author)

  5. Biological effects on human health due to radiofrequency/microwave exposure

    DEFF Research Database (Denmark)

    Breckenkamp, Jürgen; Berg, Gabriele; Blettner, Maria

    2003-01-01

    We evaluated the methods and results of nine cohort studies dealing with the biological effects on human health from exposure to radiofrequencies/microwaves, published between 1980 and 2002. The size of the cohorts varied between 304 (3,362 person years) and nearly 200,000 persons (2.7 million......, however, inconsistent. The most important limitations of the studies were the lack of measurements referring to past and current exposures and, thus, the unknown details on actual exposure, the use of possibly biased data as well as the lack of adjustment for potential confounders and the use of indirect...

  6. Large-scale projects in the amazon and human exposure to mercury: The case-study of the Tucuruí Dam.

    Science.gov (United States)

    Arrifano, Gabriela P F; Martín-Doimeadios, Rosa C Rodríguez; Jiménez-Moreno, María; Ramírez-Mateos, Vanesa; da Silva, Núbia F S; Souza-Monteiro, José Rogério; Augusto-Oliveira, Marcus; Paraense, Ricardo S O; Macchi, Barbarella M; do Nascimento, José Luiz M; Crespo-Lopez, Maria Elena

    2018-01-01

    The Tucuruí Dam is one of the largest dams ever built in the Amazon. The area is not highly influenced by gold mining as a source of mercury contamination. Still, we recently noted that one of the most consumed fishes (Cichla sp.) is possibly contaminated with methylmercury. Therefore, this work evaluated the mercury content in the human population living near the Tucuruí Dam. Strict exclusion/inclusion criteria were applied for the selection of participants avoiding those with altered hepatic and/or renal functions. Methylmercury and total mercury contents were analyzed in hair samples. The median level of total mercury in hair was above the safe limit (10µg/g) recommended by the World Health Organization, with values up to 75µg/g (about 90% as methylmercury). A large percentage of the participants (57% and 30%) showed high concentrations of total mercury (≥ 10µg/g and ≥ 20µg/g, respectively), with a median value of 12.0µg/g. These are among the highest concentrations ever detected in populations living near Amazonian dams. Interestingly, the concentrations are relatively higher than those currently shown for human populations highly influenced by gold mining areas. Although additional studies are needed to confirm the possible biomagnification and bioaccumulation of mercury by the dams in the Amazon, our data already support the importance of adequate impact studies and continuous monitoring. More than 400 hydropower dams are operational or under construction in the Amazon, and an additional 334 dams are presently planned/proposed. Continuous monitoring of the populations will assist in the development of prevention strategies and government actions to face the problem of the impacts caused by the dams. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Human exposure to mercury in a compact fluorescent lamp manufacturing area: By food (rice and fish) consumption and occupational exposure

    International Nuclear Information System (INIS)

    Liang, Peng; Feng, Xinbin; Zhang, Chan; Zhang, Jin; Cao, Yucheng; You, Qiongzhi; Leung, Anna Oi Wah; Wong, Ming-Hung; Wu, Sheng-Chun

    2015-01-01

    To investigate human Hg exposure by food consumption and occupation exposure in a compact fluorescent lamp (CFL) manufacturing area, human hair and rice samples were collected from Gaohong town, Zhejiang Province, China. The mean values of total mercury (THg) and methylmercury (MeHg) concentrations in local cultivated rice samples were significantly higher than in commercial rice samples which indicated that CFL manufacturing activities resulted in Hg accumulation in local rice samples. For all of the study participants, significantly higher THg concentrations in human hair were observed in CFL workers compared with other residents. In comparison, MeHg concentrations in human hair of residents whose diet consisted of local cultivated rice were significantly higher than those who consumed commercial rice. These results demonstrated that CFL manufacturing activities resulted in THg accumulation in the hair of CFL workers. However, MeHg in hair were mainly affected by the sources of rice of the residents. - Highlights: • Rice samples were contaminated by Compact fluorescent lamp (CFL) manufacturing. • CFL manufacturing lead to THg accumulation in human hair. • MeHg in human hair were mainly affected by the sources of rice. • MeHg intake from fish consumption was lower than that from rice consumption. • PDI of MeHg by food consumption was below the guidelines for public health concern. - CFL manufacturing activities result in Hg accumulation in local rice samples and hair of CFL workers. However, MeHg in hair were mainly affected by sources of rice

  8. Probabilistic integrated risk assessment of human exposure risk to environmental bisphenol A pollution sources.

    Science.gov (United States)

    Fu, Keng-Yen; Cheng, Yi-Hsien; Chio, Chia-Pin; Liao, Chung-Min

    2016-10-01

    Environmental bisphenol A (BPA) exposure has been linked to a variety of adverse health effects such as developmental and reproductive issues. However, establishing a clear association between BPA and the likelihood of human health is complex yet fundamentally uncertain. The purpose of this study was to assess the potential exposure risks from environmental BPA among Chinese population based on five human health outcomes, namely immune response, uterotrophic assay, cardiovascular disease (CVD), diabetes, and behavior change. We addressed these health concerns by using a stochastic integrated risk assessment approach. The BPA dose-dependent likelihood of effects was reconstructed by a series of Hill models based on animal models or epidemiological data. We developed a physiologically based pharmacokinetic (PBPK) model that allows estimation of urinary BPA concentration from external exposures. Here we showed that the daily average exposure concentrations of BPA and urinary BPA estimates were consistent with the published data. We found that BPA exposures were less likely to pose significant risks for infants (0-1 year) and adults (male and female >20 years) with human long-term BPA susceptibility in relation to multiple exposure pathways, and for informing the public of the negligible magnitude of environmental BPA pollution impacts on human health.

  9. Human exposure, biomarkers, and fate of organotins in the environment.

    Science.gov (United States)

    Okoro, Hussein K; Fatoki, Olalekan S; Adekola, Folahan A; Ximba, Bhekumusa J; Snyman, Reinette G; Opeolu, Beatrice

    2011-01-01

    Organotin compounds result from the addition of organic moieties to inorganic tin.Thus, one or more tin-carbon bonds exist in each organotin molecule. The organo-tin compounds are ubiquitous in the environment. Organotin compounds have many uses, including those as fungicides and stabilizers in plastics, among others in industry. The widespread use of organotins as antifouling agents in boat paints has resulted in pollution of freshwater and marine ecosystems. The presence of organotin compounds in freshwater and marine ecosystems is now understood to be a threat, because of the amounts found in water and the toxicity of some organotin compounds to aquatic organisms, and perhaps to humans as well. Organotin com-pounds are regarded by many to be global pollutants of a stature similar to biphenyl,mercury, and the polychlorinated dibenzodioxins. This stature results from the high toxicity, persistence, bioaccumulation, and endocrine disruptive features of even very low levels of selected organotin compounds.Efforts by selected governmental agencies and others have been undertaken to find a global solution to organotin pollution. France was the first country to ban the use of the organotins in 1980. This occurred before the international maritime organization (IMO) called for a global treaty to ban the application of tributyltin (TBT)-based paints. In this chapter, we review the organotin compounds with emphasis on the human exposure, fate, and distribution of them in the environment. The widespread use of the organotins and their high stability have led to contamination of some aquatic ecosystems. As a result, residues of the organotins may reach humans via food consumption. Notwithstanding the risk of human exposure, only limited data are available on the levels at which the organotins exist in foodstuffs consumed by humans. Moreover, the response of marine species to the organotins, such as TBT, has not been thoroughly investigated. Therefore, more data on the

  10. Human health implications from co-exposure to aflatoxins and fumonisins in maize-based foods in Latin America: Guatemala as a case study

    Science.gov (United States)

    Co-occurence of fumonisin B1 (FB1) and aflatoxin B1 (AFB1) in maize has been demonstrated in many surveys. Combined-exposure to FB1 and AFB1 was of concern to the Joint FAO/WHO Expert Committee on Food Additives because of the known genotoxicity of AFB1 and the ability of FB1 to induce regenerative...

  11. An incident study about acute and chronic human exposure to uranium by high-resolution inductively coupled plasma mass spectrometry (HR-ICPMS)

    NARCIS (Netherlands)

    Krystek, Petra; Ritsema, Rob

    2008-01-01

    From the year 2003 to 2005 around 1700 Dutch soldiers made a part of the international stabilisation force in Iraq. An incident happened as a group of four Dutch soldiers found a 30 mm bullet identified as containing depleted uranium (DU). The main pathway of the acute exposure is via inhalation of

  12. Human dermal absorption of chlorinated organophosphate flame retardants; implications for human exposure

    Energy Technology Data Exchange (ETDEWEB)

    Abou-Elwafa Abdallah, Mohamed, E-mail: mae_abdallah@yahoo.co.uk [Division of Environmental Health and Risk Management, School of Geography, Earth, and Environmental Sciences, University of Birmingham, Birmingham B15 2TT (United Kingdom); Department of Analytical Chemistry, Faculty of Pharmacy, Assiut University, 71526 Assiut (Egypt); Pawar, Gopal; Harrad, Stuart [Division of Environmental Health and Risk Management, School of Geography, Earth, and Environmental Sciences, University of Birmingham, Birmingham B15 2TT (United Kingdom)

    2016-01-15

    Tris-2-chloroethyl phosphate (TCEP), tris (1-chloro-2-propyl) phosphate (TCIPP) and tris-1,3-dichloropropyl phosphate (TDCIPP) are organophosphate flame retardants (PFRs) widely applied in a plethora of consumer products despite their carcinogenic potential. Human dermal absorption of these PFRs is investigated for the first time using human ex vivo skin and EPISKIN™ models. Results of human ex vivo skin experiments revealed 28%, 25% and 13% absorption of the applied dose (500 ng/cm{sup 2}, finite dose) of TCEP, TCIPP and TDCIPP, respectively after 24 h exposure. The EPISKIN™ model showed enhanced permeability values (i.e. weaker barrier), that were respectively 16%, 11% and 9% for TCEP, TCIPP and TDCIPP compared to human ex vivo skin. However, this difference was not significant (P > 0.05). Estimated permeability constants (K{sub p}, cm/h) showed a significant negative correlation with log K{sub ow} for the studied contaminants. The effect of hand-washing on dermal absorption of PFRs was investigated. Washing reduced overall dermal absorption, albeit to varying degrees depending on the physicochemical properties of the target PFRs. Moreover, slight variations of the absorbed dose were observed upon changing the dosing solution from acetone to 20% Tween 80 in water, indicating the potential influence of the dose vehicle on the dermal absorption of PFRs. Finally, estimated dermal uptake of the studied PFRs via contact with indoor dust was higher in UK toddlers (median ΣPFRs = 36 ng/kg bw day) than adults (median ΣPFRs = 4 ng/kg bw day). More research is required to fully elucidate the toxicological implications of such exposure. - Highlights: • Human dermal absorption of PFRs was studied using human ex vivo skin and EPISKIN™. • Absorbed fractions of TCEP, TCIPP and TDCIPP were 28%, 25% and 13% of applied dose. • Permeability constants showed significant negative correlation to log K{sub ow} of PFRs. • Skin washing reduced the overall dermal

  13. Human dermal absorption of chlorinated organophosphate flame retardants; implications for human exposure

    International Nuclear Information System (INIS)

    Abou-Elwafa Abdallah, Mohamed; Pawar, Gopal; Harrad, Stuart

    2016-01-01

    Tris-2-chloroethyl phosphate (TCEP), tris (1-chloro-2-propyl) phosphate (TCIPP) and tris-1,3-dichloropropyl phosphate (TDCIPP) are organophosphate flame retardants (PFRs) widely applied in a plethora of consumer products despite their carcinogenic potential. Human dermal absorption of these PFRs is investigated for the first time using human ex vivo skin and EPISKIN™ models. Results of human ex vivo skin experiments revealed 28%, 25% and 13% absorption of the applied dose (500 ng/cm 2 , finite dose) of TCEP, TCIPP and TDCIPP, respectively after 24 h exposure. The EPISKIN™ model showed enhanced permeability values (i.e. weaker barrier), that were respectively 16%, 11% and 9% for TCEP, TCIPP and TDCIPP compared to human ex vivo skin. However, this difference was not significant (P > 0.05). Estimated permeability constants (K p , cm/h) showed a significant negative correlation with log K ow for the studied contaminants. The effect of hand-washing on dermal absorption of PFRs was investigated. Washing reduced overall dermal absorption, albeit to varying degrees depending on the physicochemical properties of the target PFRs. Moreover, slight variations of the absorbed dose were observed upon changing the dosing solution from acetone to 20% Tween 80 in water, indicating the potential influence of the dose vehicle on the dermal absorption of PFRs. Finally, estimated dermal uptake of the studied PFRs via contact with indoor dust was higher in UK toddlers (median ΣPFRs = 36 ng/kg bw day) than adults (median ΣPFRs = 4 ng/kg bw day). More research is required to fully elucidate the toxicological implications of such exposure. - Highlights: • Human dermal absorption of PFRs was studied using human ex vivo skin and EPISKIN™. • Absorbed fractions of TCEP, TCIPP and TDCIPP were 28%, 25% and 13% of applied dose. • Permeability constants showed significant negative correlation to log K ow of PFRs. • Skin washing reduced the overall dermal absorption of target PFRs

  14. Human bromethalin exposures reported to a U.S. Statewide Poison Control System.

    Science.gov (United States)

    Huntington, Serena; Fenik, Yelena; Vohra, Rais; Geller, Richard J

    2016-03-01

    Bromethalin is an increasingly used alternative to long-acting anticoagulant and cholecalciferol rodenticides. There are few reports of human exposures, and no existing professional society guidelines on medical management of bromethalin ingestions. The aim of this retrospective data review is to characterize bromethalin exposures reported to the California Poison Control System (CPCS) between 1997 and 2014. This is an observational retrospective case review of our statewide poison control system's electronic medical records. Following Institutional Board Review and Research Committee approvals, poison center exposures related to bromethalin were extracted using substance code and free text search strategies. Case notes of bromethalin exposures were reviewed for demographic, clinical, laboratory, and outcome information; inclusion criteria for the study was single-substance, human exposure to bromethalin. There were 129 calls related to human bromethalin exposures (three cases met exclusion criteria). The age range of cases was 7 months-90 years old, with the majority of exposures (89 cases; 70.6%), occurring in children younger than 5 years of age (median age of 2 years). Most exposures occurred in the pediatric population as a result of exploratory oral exposure. One hundred and thirteen patients (89.7%) had no effects post exposure, while 10 patients (7.9%) had a minor outcome. Adverse effects were minor, self-limited, and mostly gastrointestinal upset. There were no moderate, major, or fatal effects in our study population. The approximate ingested dose, available in six cases, ranged from 0.067 mg/kg to 0.3 mg/kg (milligrams of bromethalin ingested per kilogram of body weight), and no dose-symptom threshold could be established from this series. Exposures were not confirmed through urine or serum laboratory testing. The prognosis for most accidental ingestions appears to be excellent. However, bromethalin exposures may result in a higher number of

  15. Mathematical Models of Human Hematopoiesis Following Acute Radiation Exposure

    Science.gov (United States)

    2014-05-01

    response of 11 subjects from Chernobyl 1986 . . . . . . 104 B.8 Chernobyl case studies: Platelet data . . . . . . . . . . . . . . . . . . . . . . 105 B...9 Chernobyl case studies: Granulocyte data . . . . . . . . . . . . . . . . . . . 106 B.10 Chernobyl case studies: Lymphocyte data...information for use in nuclear disaster preparedness planning. Understanding how biological systems change after radiation exposure provides insight on the

  16. Level changes and human dietary exposure assessment of halogenated flame retardant levels in free-range chicken eggs: A case study of a former e-waste recycling site, South China.

    Science.gov (United States)

    Huang, Chen-Chen; Zeng, Yan-Hong; Luo, Xiao-Jun; Tang, Bin; Liu, Yin-E; Ren, Zi-He; Mai, Bi-Xian

    2018-04-06

    To assess the impacts of e-waste regulations on environmental pollution, we built on a previous study from 2010 to investigate the levels and human dietary exposure of halogenated flame retardants (HFRs) in free-range chicken eggs from Baihe village in 2013 and 2016. The concentrations of PBDEs, PBBs, HBCDs, and DBDPE showed a significant decrease (pexposure estimates suggested high dietary intake of HFRs via home-produced eggs. As for PBDEs, considering the worst situation (highly polluted eggs were consumed), the margin of exposure (MOE) of BDE99 for both adults and children were 1.5 and 0.3 in 2013, and 1.1 and 0.2 in 2016, respectively, which were below 2.5. According to the CONTAM panel, an MOE larger than 2.5 indicates no health concern. Therefore, these MOE values represent a significant potential health concern due to the adverse impacts of PBDEs on human neurodevelopment and fertility. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Considerations for the design and technical setup of a human whole-body exposure chamber.

    Science.gov (United States)

    Monsé, Christian; Sucker, Kirsten; van Thriel, Christoph; Broding, Horst Christoph; Jettkant, Birger; Berresheim, Hans; Wiethege, Thorsten; Käfferlein, Heiko; Merget, Rolf; Bünger, Jürgen; Brüning, Thomas

    2012-01-01

    Exposures to air contaminants, such as chemical vapors and particulate matter, pose important health hazards at workplaces. Short-term experimental exposures to chemical vapors and particles in humans are a promising attempt to investigate acute effects of such hazards. However, a significant challenge in this field is the determination of effects of co-exposures to more than one chemical or mixtures of chemical vapors and/or particles. To overcome such a challenge, studies have to be conducted under standardized exposure characterization and real time measurements, if possible. A new exposure laboratory (ExpoLab) was installed at IPA, combining sophisticated engineering designs with new analytical techniques, to fulfill these requirements. Low-dose as well as high-dose exposure scenarios are achieved by means of a calibration-gas-generator. Exposure monitoring can be carried out with a high performance real time mass spectrometer and other suitable analyzers (e.g. gas chromatograph). Numerous automated security facilities guarantee the physical integrity of the volunteers, and the waste atmosphere is removed using either charcoal filtration or catalytic post-combustion. Measurements of sulfur hexafluoride, carbon dioxide, aniline and carbon black are presented to demonstrate the performance of the exposure unit with respect to the temporal and spatial stability of generated atmospheres. The variations of generated contents in the atmospheres at steady state are slightly higher than the measurement precision of the analyzers (the typical standard deviation of generated atmospheres is standards in validity and reliability of generating and measuring exposure atmospheres.

  18. Automated scoring of lymphocyte micronuclei by the MetaSystems Metafer image cytometry system and its application in studies of human mutagen sensitivity and biodosimetry of genotoxin exposure

    Czech Academy of Sciences Publication Activity Database

    Rössnerová, Andrea; Špátová, Milada; Schunck, CH.; Šrám, Radim

    2011-01-01

    Roč. 26, č. 1 (2011), s. 169-175 ISSN 0267-8357 R&D Projects: GA MŽP(CZ) SP/1B3/8/08; GA AV ČR 1QS500390506 Institutional research plan: CEZ:AV0Z50390512 Keywords : automated micronucleus assay * environmental exposure * Metasystems Metafer image cytometry system Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 3.183, year: 2011

  19. The Human Exposure Potential from Propylene Releases to the Environment

    Directory of Open Access Journals (Sweden)

    David A. Morgott

    2018-01-01

    Full Text Available A detailed literature search was performed to assess the sources, magnitudes and extent of human inhalation exposure to propylene. Exposure evaluations were performed at both the community and occupational levels for those living or working in different environments. The results revealed a multitude of pyrogenic, biogenic and anthropogenic emission sources. Pyrogenic sources, including biomass burning and fossil fuel combustion, appear to be the primary contributors to atmospheric propylene. Despite a very short atmospheric lifetime, measurable levels could be detected in highly remote locations as a result of biogenic release. The indoor/outdoor ratio for propylene has been shown to range from about 2 to 3 in non-smoking homes, which indicates that residential sources may be the largest contributor to the overall exposure for those not occupationally exposed. In homes where smoking takes place, the levels may be up to thirty times higher than non-smoking residences. Atmospheric levels in most rural regions are typically below 2 ppbv, whereas the values in urban levels are much more variable ranging as high as 10 ppbv. Somewhat elevated propylene exposures may also occur in the workplace; especially for firefighters or refinery plant operators who may encounter levels up to about 10 ppmv.

  20. Development of human exposure standards for radio frequency fields

    International Nuclear Information System (INIS)

    Lin, James C.

    2000-01-01

    Historical aspects of the problem of developing human exposure standards for radio frequency (RF) electromagnetic fields are discussed. It is shown that biological effects and health implications of radiofrequency (RF) electromagnetic fields have been a subject of scientific investigation for more than 50 years. It has become a focus of attention because of the expanded use of RF radiation in the frequency range between 300 MHz and 6 GHz for wireless communication over the past decade. Another cause for the attention is the uncertainty of some observed responses and lack of understanding of the mechanism of interaction of RF electromagnetic fields with biological systems. At present, considerable efforts are devoted to developing and revising RF exposure standards. Each of these efforts should aim to make explicit the philosophy and process by which they reason and decide guidelines for deeming exposure as safe. Furthermore, the reconciliation of philosophies of protection will definitely be an asset, in practice, to those interested in international harmonization of RF exposure standards [ru

  1. Analysis of Cigarette Smoke Deposition Within an In Vitro Exposure System for Simulating Exposure in the Human Respiratory Tract

    Directory of Open Access Journals (Sweden)

    Ishikawa Shinkichi

    2016-01-01

    Full Text Available For the risk assessment of airborne chemicals, a variety of in vitro direct exposure systems have been developed to replicate airborne chemical exposure in vivo. Since cells at the air-liquid interface are exposed to cigarette smoke as an aerosol in direct exposure systems, it is possible to reproduce the situation of cigarette smoke exposure in the human respiratory system using this device. However it is difficult to know whether the exposed cigarette smoke in this system is consistent with the smoke retained in the human respiratory tract. The purpose of this study is to clarify this point using the CULTEX® RFS module which is a recently developed direct exposure system. For this purpose, solanesol and acetaldehyde were respectively chosen as the particulate and gas/vapor phase representatives of smoke constituents, and their deposition and balance per unit area of cell culture surface of the RFS module were measured (dosimetry. We also conducted human retention studies to compare with the dosimetry data. By comparing inhaled smoke and exhaled smoke under three inhalation conditions, we estimated the regional retention and balance of each representative per unit surface area of the respiratory tract (mouth, bronchi, and alveoli separately. The deposition of solanesol and acetaldehyde per unit area of cell culture surface in the RFS module decreased dependent on the dilution flow rate and ranged from 0.26-0.0076%/cm2 in our experimental conditions. The ratio of deposited acetaldehyde to deposited solanesol ranged from 0.96-1.96 in the RFS module. The retention of solanesol and acetaldehyde per unit surface area in the mouth and the bronchi ranged from 0.095-0.0083%/cm2 in this study. The retention per unit surface area of alveoli was far lower than in the other two regions (0.0000063%/cm2. The ratio of retained acetaldehyde to retained solanesol ranged from 0.54-1.97. From these results, we concluded that the CULTEX® RFS module can simulate

  2. Dose-rate models for human survival after exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Jones, T.D.; Morris, M.D.; Young, R.W.

    1987-01-01

    This paper reviews new estimates of the LD 50 in man by Mole and by Rotblat, the biological processes contributing to hematologic death, the collection of animal experiments dealing with hematologic death, and the use of regression analysis to make new estimates of human mortality based on all relevant animal studies. Regression analysis of animal mortality data has shown that mortality is dependent strongly on dose rate, species, body weight, and time interval over which the exposure is delivered. The model has predicted human LD 50 s of 194, 250, 310, and 360 rad to marrow when the exposure time is a minute, an hour, a day, and a week, respectively

  3. Dose-rate models for human survival after exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Jones, T.D.; Morris, M.D.; Young, R.W.

    1986-01-01

    This paper reviews new estimates of the L 50 in man by Mole and by Rotblat, the biological processes contributing to hematologic death, the collection of animal experiments dealing with hematologic death, and the use of regression analysis to make new estimates of human mortality based on all relevant animal studies. Regression analysis of animal mortality data has shown that mortality is dependent strongly on dose rate, species, body weight, and time interval over which the exposure is delivered. The model has predicted human LD 50 s of 194, 250, 310, and 360 rad to marrow when the exposure time is a minute, an hour, a day, and a week, respectively

  4. Human convective boundary layer and its impact on personal exposure

    DEFF Research Database (Denmark)

    Licina, Dusan

    generated by heat sources are gaining more prominent influence in space airflow formation and on the indoor environment overall. In such spaces with low air supply velocity, air mixing is minimized and the pollution emitted from localized indoor sources is non-uniformly distributed. The large spatial......People spend most of their time indoors and they are constantly exposed to pollution that affects their health, comfort and productivity. Due to strong economic and environmental pressures to reduce building energy consumption, low air velocity design is gaining popularity; hence buoyancy flows...... in inaccurate exposure prediction. This highlights the importance of a detailed understanding of the complex air movements that take place in the vicinity of the human body and their impact on personal exposure. The two objectives of the present work are: (i) to examine the extent to which the room air...

  5. Dosimetry Methods for Human Exposure to Non-Ionising Radiation

    International Nuclear Information System (INIS)

    Poljak, D.; Sarolic, A.; Doric, V.; Peratta, C.; Peratta, A.

    2011-01-01

    The paper deals with human exposure to electromagnetic fields from extremely low frequencies (ELF) to GSM frequencies. The problem requires (1) the assessment of external field generated by electromagnetic interference (EMI) source at a given frequency (incident field dosimetry) and then (2) the assessment of corresponding fields induced inside the human body (internal field dosimetry). Several methods used in theoretical and experimental dosimetry are discussed within this work. Theoretical dosimetry models at low frequencies are based on quasistatic approaches, while analyses at higher frequencies use the full-wave models. Experimental techniques involve near and far field measurement. Human exposure to power lines, transformer substations, power line communication (PLC) systems, Radio Frequency Identification (RFID) antennas and GSM base station antenna systems is analyzed. The results o are compared to the exposure limits proposed by relevant safety guidelines. Theoretical incident dosimetry used in this paper is based on the set of Pocklington integro-differential equations for the calculation of the current distribution and subsequently radiated field from power lines. Experimental incident dosimetry techniques involve measurement techniques of fields radiated by RFID antennas and GSM base station antennas. First example set of numerical results is related to the internal dosimetry of realistic well-grounded body model exposed to vertical component of the electric field E = 10 kV/m generated by high voltage power line. The results obtained via the HNA model exceed the ICNIRP basic restrictions for public exposure (2 mA/m 2 ) in knee (8.6 mA/m 2 ) and neck (9.8 mA/m 2 ) and for occupational exposure (10 mA/m 2 ) in ankle (32 mA/m 2 ). In the case of a conceptual model of a realistic human body inside a transformer substation room touching a control panel at the potential φ0 = 400 V and with two scenarios for dry-air between worker's hand and panel, the values

  6. Human Exposure and Health Effects of Inorganic and Elemental Mercury

    Science.gov (United States)

    Zheng, Wei

    2012-01-01

    Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety. PMID:23230464

  7. A comprehensive assessment of human exposure to phthalates from environmental media and food in Tianjin, China.

    Science.gov (United States)

    Ji, Yaqin; Wang, Fumei; Zhang, Leibo; Shan, Chunyan; Bai, Zhipeng; Sun, Zengrong; Liu, Lingling; Shen, Boxiong

    2014-08-30

    A total of 448 samples including foodstuffs (rice, steamed bun, vegetables, meat, poultry, fish, milk and fruits), ambient PM10, drinking water, soil, indoor PM10 and indoor dust samples from Tianjin were obtained to determine the distribution of six priority phthalates (PAEs) and assess the human exposure to them. The results indicated that DBP and DEHP were the most frequently detected PAEs in these samples. The concentrations of PAEs in environmental media were higher than those in food. We estimated the daily intake (DI) of PAEs via ingestion, inhalation and dermal absorption from five sources (food, water, air, dust and soil). Dietary intake was the main exposure source to DEP, BBP, DEHP and DOP, whereas water ingestion/absorption was the major source of exposure to DBP, DEHP and DOP. Although food and water were the overwhelmingly predominant sources of PAEs intake by Tianjin population, contaminated air was another important source of DMP, DEP and DBP contributing to up to 45% of the exposure. The results of this study will help in understanding the major pathways of human exposure to PAEs. These findings also suggest that human exposure to phthalate esters via the environment should not be overlooked. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Case definitions for human poisonings postulated to palytoxins exposure.

    Science.gov (United States)

    Tubaro, A; Durando, P; Del Favero, G; Ansaldi, F; Icardi, G; Deeds, J R; Sosa, S

    2011-03-01

    A series of case reports and anecdotal references describe the adverse effects on human health ascribed to the marine toxin palytoxin (PLTX) after different exposure routes. They include poisonings after oral intake of contaminated seafood, but also inhalation and cutaneous/systemic exposures after direct contact with aerosolized seawater during Ostreopsis blooms and/or through maintaining aquaria containing cnidarian zoanthids. The symptoms commonly recorded during PLTX intoxication are general malaise and weakness, associated with myalgia, respiratory effects, impairment of the neuromuscular apparatus and abnormalities in cardiac function. Systemic symptoms are often recorded together with local damages whose intensity varies according to the route and length of exposure. Gastrointestinal malaise or respiratory distress is common for oral and inhalational exposure, respectively. In addition, irritant properties of PLTX probably account for the inflammatory reactions typical of cutaneous and inhalational contact. Unfortunately, the toxin identification and/or quantification are often incomplete or missing and cases of poisoning are indirectly ascribed to PLTXs, according only to symptoms, anamnesis and environmental/epidemiological investigations (i.e. zoanthid handling or ingestion of particular seafood). Based on the available literature, we suggest a "case definition of PLTX poisonings" according to the main exposure routes, and, we propose the main symptoms to be checked, as well as, hemato-clinical analysis to be carried out. We also suggest the performance of specific analyses both on biological specimens of patients, as well as, on the contaminated materials responsible for the poisoning. A standardized protocol for data collection could provide a more rapid and reliable diagnosis of palytoxin-poisoning, but also the collection of necessary data for the risk assessment for this family of toxins. Copyright © 2011 Elsevier Ltd. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-31

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-31

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

  11. Prenatal Exposure to Progesterone Affects Sexual Orientation in Humans.

    Science.gov (United States)

    Reinisch, June M; Mortensen, Erik Lykke; Sanders, Stephanie A

    2017-07-01

    Prenatal sex hormone levels affect physical and behavioral sexual differentiation in animals and humans. Although prenatal hormones are theorized to influence sexual orientation in humans, evidence is sparse. Sexual orientation variables for 34 prenatally progesterone-exposed subjects (17 males and 17 females) were compared to matched controls (M age = 23.2 years). A case-control double-blind design was used drawing on existing data from the US/Denmark Prenatal Development Project. Index cases were exposed to lutocyclin (bioidentical progesterone = C 21 H 30 O 2 ; M W : 314.46) and no other hormonal preparation. Controls were matched on 14 physical, medical, and socioeconomic variables. A structured interview conducted by a psychologist and self-administered questionnaires were used to collect data on sexual orientation, self-identification, attraction to the same and other sex, and history of sexual behavior with each sex. Compared to the unexposed, fewer exposed males and females identified as heterosexual and more of them reported histories of same-sex sexual behavior, attraction to the same or both sexes, and scored higher on attraction to males. Measures of heterosexual behavior and scores on attraction to females did not differ significantly by exposure. We conclude that, regardless of sex, exposure appeared to be associated with higher rates of bisexuality. Prenatal progesterone may be an underappreciated epigenetic factor in human sexual and psychosexual development and, in light of the current prevalence of progesterone treatment during pregnancy for a variety of pregnancy complications, warrants further investigation. These data on the effects of prenatal exposure to exogenous progesterone also suggest a potential role for natural early perturbations in progesterone levels in the development of sexual orientation.

  12. Soil is an important pathway of human lead exposure.

    OpenAIRE

    Mielke, H W; Reagan, P L

    1998-01-01

    This review shows the equal or greater importance of leaded gasoline-contaminated dust compared to lead-based paint to the child lead problem, and that soil lead, resulting from leaded gasoline and pulverized lead-based paint, is at least or more important than lead-based paint (intact and not pulverized) as a pathway of human lead exposure. Because lead-based paint is a high-dose source, the biologically relevant dosage is similar to lead in soil. Both lead-based paint and soil lead are asso...

  13. Quantitative assessment of human and pet exposure to Salmonella associated with dry pet foods.

    Science.gov (United States)

    Lambertini, Elisabetta; Buchanan, Robert L; Narrod, Clare; Ford, Randall M; Baker, Robert C; Pradhan, Abani K

    2016-01-04

    Recent Salmonella outbreaks associated with dry pet foods and treats highlight the importance of these foods as previously overlooked exposure vehicles for both pets and humans. In the last decade efforts have been made to raise the safety of this class of products, for instance by upgrading production equipment, cleaning protocols, and finished product testing. However, no comprehensive or quantitative risk profile is available for pet foods, thus limiting the ability to establish safety standards and assess the effectiveness of current and proposed Salmonella control measures. This study sought to develop an ingredients-to-consumer quantitative microbial exposure assessment model to: 1) estimate pet and human exposure to Salmonella via dry pet food, and 2) assess the impact of industry and household-level mitigation strategies on exposure. Data on prevalence and concentration of Salmonella in pet food ingredients, production process parameters, bacterial ecology, and contact transfer in the household were obtained through literature review, industry data, and targeted research. A probabilistic Monte Carlo modeling framework was developed to simulate the production process and basic household exposure routes. Under the range of assumptions adopted in this model, human exposure due to handling pet food is null to minimal if contamination occurs exclusively before extrusion. Exposure increases considerably if recontamination occurs post-extrusion during coating with fat, although mean ingested doses remain modest even at high fat contamination levels, due to the low percent of fat in the finished product. Exposure is highly variable, with the distribution of doses ingested by adult pet owners spanning 3Log CFU per exposure event. Child exposure due to ingestion of 1g of pet food leads to significantly higher doses than adult doses associated with handling the food. Recontamination after extrusion and coating, e.g., via dust or equipment surfaces, may also lead to

  14. TOWARDS RELIABLE AND COST-EFFECTIVE OZONE EXPOSURE ASSESSMENT: PARAMETER EVALUATION AND MODEL VALIDATION USING THE HARVARD SOUTHERN CALIFORNIA CHRONIC OZONE EXPOSURE STUDY DATA

    Science.gov (United States)

    Accurate assessment of chronic human exposure to atmospheric criteria pollutants, such as ozone, is critical for understanding human health risks associated with living in environments with elevated ambient pollutant concentrations. In this study, we analyzed a data set from a...

  15. Dynamics of the transcriptome response of cultured human embryonic stem cells to ionizing radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Sokolov, Mykyta V., E-mail: sokolovm@mail.nih.gov [Nuclear Medicine Division, Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892 (United States); Panyutin, Irina V., E-mail: ipanyutinv@mail.nih.gov [Nuclear Medicine Division, Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892 (United States); Panyutin, Igor G., E-mail: igorp@helix.nih.gov [Nuclear Medicine Division, Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892 (United States); Neumann, Ronald D., E-mail: rneumann@mail.nih.gov [Nuclear Medicine Division, Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892 (United States)

    2011-05-10

    One of the key consequences of exposure of human cells to genotoxic agents is the activation of DNA damage responses (DDR). While the mechanisms underpinning DDR in fully differentiated somatic human cells have been studied extensively, molecular signaling events and pathways involved in DDR in pluripotent human embryonic stem cells (hESC) remain largely unexplored. We studied changes in the human genome-wide transcriptome of H9 hESC line following exposures to 1 Gy of gamma-radiation at 2 h and 16 h post-irradiation. Quantitative real-time PCR was performed to verify the expression data for a subset of genes. In parallel, the cell growth, DDR kinetics, and expression of pluripotency markers in irradiated hESC were monitored. The changes in gene expression in hESC after exposure to ionizing radiation (IR) are substantially different from those observed in somatic human cell lines. Gene expression patterns at 2 h post-IR showed almost an exclusively p53-dependent, predominantly pro-apoptotic, signature with a total of only 30 up-regulated genes. In contrast, the gene expression patterns at 16 h post-IR showed 354 differentially expressed genes, mostly involved in pro-survival pathways, such as increased expression of metallothioneins, ubiquitin cycle, and general metabolism signaling. Cell growth data paralleled trends in gene expression changes. DDR in hESC followed the kinetics reported for human somatic differentiated cells. The expression of pluripotency markers characteristic of undifferentiated hESC was not affected by exposure to IR during the time course of our analysis. Our data on dynamics of transcriptome response of irradiated hESCs may provide a valuable tool to screen for markers of IR exposure of human cells in their most naive state; thus unmasking the key elements of DDR; at the same time, avoiding the complexity of interpreting distinct cell type-dependent genotoxic stress responses of terminally differentiated cells.

  16. Dynamics of the transcriptome response of cultured human embryonic stem cells to ionizing radiation exposure

    International Nuclear Information System (INIS)

    Sokolov, Mykyta V.; Panyutin, Irina V.; Panyutin, Igor G.; Neumann, Ronald D.

    2011-01-01

    One of the key consequences of exposure of human cells to genotoxic agents is the activation of DNA damage responses (DDR). While the mechanisms underpinning DDR in fully differentiated somatic human cells have been studied extensively, molecular signaling events and pathways involved in DDR in pluripotent human embryonic stem cells (hESC) remain largely unexplored. We studied changes in the human genome-wide transcriptome of H9 hESC line following exposures to 1 Gy of gamma-radiation at 2 h and 16 h post-irradiation. Quantitative real-time PCR was performed to verify the expression data for a subset of genes. In parallel, the cell growth, DDR kinetics, and expression of pluripotency markers in irradiated hESC were monitored. The changes in gene expression in hESC after exposure to ionizing radiation (IR) are substantially different from those observed in somatic human cell lines. Gene expression patterns at 2 h post-IR showed almost an exclusively p53-dependent, predominantly pro-apoptotic, signature with a total of only 30 up-regulated genes. In contrast, the gene expression patterns at 16 h post-IR showed 354 differentially expressed genes, mostly involved in pro-survival pathways, such as increased expression of metallothioneins, ubiquitin cycle, and general metabolism signaling. Cell growth data paralleled trends in gene expression changes. DDR in hESC followed the kinetics reported for human somatic differentiated cells. The expression of pluripotency markers characteristic of undifferentiated hESC was not affected by exposure to IR during the time course of our analysis. Our data on dynamics of transcriptome response of irradiated hESCs may provide a valuable tool to screen for markers of IR exposure of human cells in their most naive state; thus unmasking the key elements of DDR; at the same time, avoiding the complexity of interpreting distinct cell type-dependent genotoxic stress responses of terminally differentiated cells.

  17. Occurrence, sources and human exposure assessment of SCCPs in indoor dust of northeast China.

    Science.gov (United States)

    Liu, Li-Hua; Ma, Wan-Li; Liu, Li-Yan; Huo, Chun-Yan; Li, Wen-Long; Gao, Chong-Jing; Li, Hai-Ling; Li, Yi-Fan; Chan, Hing Man

    2017-06-01

    Short-chain chlorinated paraffins (SCCPs) are widely used chemicals in household products and might cause adverse human health effects. However, limited information is available on the occurrence of SCCPs in indoor environments and their exposure risks on humans. In this study the concentrations, profiles and human exposure of SCCPs in indoor dust from five different indoor environments, including commercial stores, residential apartments, dormitories, offices and laboratories were characterized. The SCCPs levels ranged from 10.1 to 173.0 μg/g, with the median and mean concentration of 47.2 and 53.6 μg/g, respectively. No significant difference was found on concentrations among the five microenvironments. The most abundant compounds in indoor dust samples were homologues of C 13 group, Cl 7 group and N 20 (N is the total number of C and Cl) group. In the five microenvironments, commercial stores were more frequently exposed to shorter carbon chained and higher chlorinated homologues. Three potential sources for SCCPs were identified by the multiple linear regression of factor score model and correspondence analysis. The major sources of SCCPs in indoor dust were technical mixtures of CP-42 (42% chlorine, w/w) and CP-52 b (52% chlorine, w/w). The total daily exposure doses and hazard quotients (HQ) were calculated by the human exposure models, and they were all below the reference doses and threshold values, respectively. Monte Carlo simulation was applied to predict the human exposure risk of SCCPs. Infants and toddlers were at risk of SCCPs based on predicted HQ values, which were exceeded the threshold for neoplastic effects in the worst case. Our results on the occurrences, sources and human exposures of SCCPs will be useful to provide a better understanding of SCCPs behaviors in indoor environment in China, and to support environmental risk evaluation and regulation of SCCPs in the world. Copyright © 2017. Published by Elsevier Ltd.

  18. Oral bioaccessibility and human exposure to anthropogenic and geogenic mercury in urban, industrial and mining areas

    NARCIS (Netherlands)

    Rodrigues, S.M.; Coelho, C.; Cruz, N.; Monteiro, R.J.R.; Henriques, B.; Duarte, A.C.; Romkens, P.F.A.M.; Pereira, E.

    2014-01-01

    The objective of this study was to characterize the link between bioaccessibility and fractionation of mercury (Hg) in soils and to provide insight into human exposure to Hg due to inhalation of airborne soil particles and hand-to-mouth ingestion of Hg-bearing soil. Mercury in soils from mining,

  19. Exposure to perfluorinated compounds and human semen quality in arctic and European populations

    NARCIS (Netherlands)

    Toft, G.; Jönsson, B.A.G.; Lindh, C.H.; Giwercman, A.; Spano, M.; Heederik, D.J.J.; Lenters, V.C.; Vermeulen, R.C.H.; Rylander, L.; Pedersen, H.S.; Ludwicki, J.K.; Zviezdai, V.; Bonde, J.P.

    2012-01-01

    BACKGROUND Perfluorinated compounds (PFCs) have been suspected to adversely affect human reproductive health. The aim of this study was to investigate the associations between PFC exposure and male semen quality. METHODS PFCs were measured in serum from 588 partners of pregnant women from Greenland,

  20. Truncated Levy flights and agenda-based mobility are useful for the assessment of personal human exposure

    International Nuclear Information System (INIS)

    Schlink, Uwe; Ragas, Ad M.J.

    2011-01-01

    Receptor-oriented approaches can assess the individual-specific exposure to air pollution. In such an individual-based model we analyse the impact of human mobility to the personal exposure that is perceived by individuals simulated in an exemplified urban area. The mobility models comprise random walk (reference point mobility, RPM), truncated Levy flights (TLF), and agenda-based walk (RPMA). We describe and review the general concepts and provide an inter-comparison of these concepts. Stationary and ergodic behaviour are explained and applied as well as performance criteria for a comparative evaluation of the investigated algorithms. We find that none of the studied algorithm results in purely random trajectories. TLF and RPMA prove to be suitable for human mobility modelling, because they provide conditions for very individual-specific trajectories and exposure. Suggesting these models we demonstrate the plausibility of their results for exposure to air-borne benzene and the combined exposure to benzene and nonane. - Highlights: → Human exposure to air pollutants is influenced by a person's movement in the urban area. → We provide a simulation study of approaches to modelling personal exposure. → Agenda-based models and truncated Levy flights are recommended for exposure assessment. → The procedure is demonstrated for benzene exposure in an urban region. - Truncated Levy flights and agenda-based mobility are useful for the assessment of personal human exposure.

  1. Mechanism-based drug exposure classification in pharmacoepidemiological studies

    NARCIS (Netherlands)

    Verdel, B.M.

    2010-01-01

    Mechanism-based classification of drug exposure in pharmacoepidemiological studies In pharmacoepidemiology and pharmacovigilance, the relation between drug exposure and clinical outcomes is crucial. Exposure classification in pharmacoepidemiological studies is traditionally based on

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

    Directory of Open Access Journals (Sweden)

    Johan Högberg

    2011-02-01

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

  3. Brief oral stimulation, but especially oral fat exposure, elevates serum triglycerides in humans

    Science.gov (United States)

    Mattes, Richard D.

    2009-01-01

    Oral exposure to dietary fat results in an early initial spike, followed by a prolonged elevation, of serum triglycerides in humans. The physiological and pathophysiological implications remain unknown. This study sought to determine the incidence of the effect, the required fat exposure duration, and its reliability. Thirty-four healthy adults participated in four to six response-driven trials held at least a week apart. They reported to the laboratory after an overnight fast, a catheter was placed in an antecubital vein, and a blood sample was obtained. Participants then ingested 50 g of safflower oil in capsules with 500 ml of water within 15 min to mimic a high fat meal but without oral fat exposure. Blood was collected 0, 10, 20, 30, 40, 50, 60, 120, 240, 360, and 480 min after capsule ingestion with different forms (full fat, nonfat, none) and durations of oral fat exposures (10 s, 5 min, 20 min, and/or 2 h). A triglyceride response (increase of triglyceride >10 mg/dl within 30 min) was observed in 88.2%, 70.5%, and 50% of participants with full-fat, nonfat, and no oral exposure, respectively. Test-retest reliability was 75% with full-fat exposure but only 45.4% with nonfat exposure. Full-fat and nonfat exposures led to comparable significant elevations of triglyceride over no oral stimulation with 10-s exposures, but full fat led to a greater rise than nonfat with 20 min of exposure. These data indicate that nutritionally relevant oral fat exposures reliably elevate serum triglyceride concentrations in most people. PMID:19074638

  4. Assessment of indirect human exposure to environmental sources of nickel: oral exposure and risk characterization for systemic effects.

    Science.gov (United States)

    De Brouwere, Katleen; Buekers, Jurgen; Cornelis, Christa; Schlekat, Christian E; Oller, Adriana R

    2012-03-01

    This paper describes the indirect human exposure to Ni via the oral route for the regional scale in the EU, together with a method to assess additional local exposure from industrial emissions. The approach fills a gap in the generic REACH guidance which is inadequate for assessing indirect environmental exposure of metals. Estimates of regional scale Ni dietary intake were derived from Ni dietary studies performed in the EU. Typical and Reasonable Worst Case dietary Ni intakes for the general population in the EU were below the oral Derived No Effect Level (DNEL) of Ni sulfate for systemic effects. Estimates for the Ni dietary intake at the local scale take into account the influence of aerial Ni deposition and transfer from soil to crops grown near industrial plants emitting Ni. The additional dietary exposure via this local contribution was small. Despite the use of conservative parameters for these processes, this method may underestimate dietary exposure around older industrial sites because REACH guidance does not account for historical soil contamination. Nevertheless, the method developed here can also be used as a screening tool for community-based risk assessment, as it accounts for historical soil pollution. Nickel exposure via drinking water was derived from databases on Ni tap water quality. A small proportion of the EU population (<5%) is likely to be exposed to tap water exceeding the EU standard (20 μg Ni/l). Taking into account the relative gastrointestinal absorption of Ni from water (30%) versus from solid matrices (5%), water intake constitutes, after dietary intake, the second most important pathway for oral Ni intake. Incidental ingestion of Ni from soil/dust at the regional scale, and also at the local scale, was low in comparison with dietary intake. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Source attribution of human campylobacteriosis at the point of exposure by combining comparative exposure assessment and subtype comparison based on comparative genomic fingerprinting.

    Directory of Open Access Journals (Sweden)

    André Ravel

    Full Text Available Human campylobacteriosis is a common zoonosis with a significant burden in many countries. Its prevention is difficult because humans can be exposed to Campylobacter through various exposures: foodborne, waterborne or by contact with animals. This study aimed at attributing campylobacteriosis to sources at the point of exposure. It combined comparative exposure assessment and microbial subtype comparison with subtypes defined by comparative genomic fingerprinting (CGF. It used isolates from clinical cases and from eight potential exposure sources (chicken, cattle and pig manure, retail chicken, beef, pork and turkey meat, and surface water collected within a single sentinel site of an integrated surveillance system for enteric pathogens in Canada. Overall, 1518 non-human isolates and 250 isolates from domestically-acquired human cases were subtyped and their subtype profiles analyzed for source attribution using two attribution models modified to include exposure. Exposure values were obtained from a concurrent comparative exposure assessment study undertaken in the same area. Based on CGF profiles, attribution was possible for 198 (79% human cases. Both models provide comparable figures: chicken meat was the most important source (65-69% of attributable cases whereas exposure to cattle (manure ranked second (14-19% of attributable cases, the other sources being minor (including beef meat. In comparison with other attributions conducted at the point of production, the study highlights the fact that Campylobacter transmission from cattle to humans is rarely meat borne, calling for a closer look at local transmission from cattle to prevent campylobacteriosis, in addition to increasing safety along the chicken supply chain.

  6. Source attribution of human campylobacteriosis at the point of exposure by combining comparative exposure assessment and subtype comparison based on comparative genomic fingerprinting.

    Science.gov (United States)

    Ravel, André; Hurst, Matt; Petrica, Nicoleta; David, Julie; Mutschall, Steven K; Pintar, Katarina; Taboada, Eduardo N; Pollari, Frank

    2017-01-01

    Human campylobacteriosis is a common zoonosis with a significant burden in many countries. Its prevention is difficult because humans can be exposed to Campylobacter through various exposures: foodborne, waterborne or by contact with animals. This study aimed at attributing campylobacteriosis to sources at the point of exposure. It combined comparative exposure assessment and microbial subtype comparison with subtypes defined by comparative genomic fingerprinting (CGF). It used isolates from clinical cases and from eight potential exposure sources (chicken, cattle and pig manure, retail chicken, beef, pork and turkey meat, and surface water) collected within a single sentinel site of an integrated surveillance system for enteric pathogens in Canada. Overall, 1518 non-human isolates and 250 isolates from domestically-acquired human cases were subtyped and their subtype profiles analyzed for source attribution using two attribution models modified to include exposure. Exposure values were obtained from a concurrent comparative exposure assessment study undertaken in the same area. Based on CGF profiles, attribution was possible for 198 (79%) human cases. Both models provide comparable figures: chicken meat was the most important source (65-69% of attributable cases) whereas exposure to cattle (manure) ranked second (14-19% of attributable cases), the other sources being minor (including beef meat). In comparison with other attributions conducted at the point of production, the study highlights the fact that Campylobacter transmission from cattle to humans is rarely meat borne, calling for a closer look at local transmission from cattle to prevent campylobacteriosis, in addition to increasing safety along the chicken supply chain.

  7. Natural and anthropogenic radiation exposure of humans in Germany

    International Nuclear Information System (INIS)

    Koelzer, Winfried

    2016-12-01

    The contribution on natural and anthropogenic radiation exposure in Germany covers the following issues: (1) natural radiation exposure: external radiation exposure - cosmic and terrestric radiation, internal radiation exposure - primordial and cosmogenic radionuclides; radiation exposure due to sola neutrinos and geo-neutrinos. (2) Anthropogenic radiation exposure: radiation exposure in medicine, radioactivity in industrial products, radiation exposure during flights, radiation exposure due to nuclear facilities, radiation exposure due to fossil energy carriers in power generation, radiation exposure due to nuclear explosions, radiation exposure due to nuclear accidents. (3) Occupational radiation exposure in Germany: radiation monitoring with personal dosimeters in medicine and industry, dose surveillance of the aviation personal, working places with increases radiation exposure by natural radiation sources.

  8. Military-Specific Exposure Factors Study

    National Research Council Canada - National Science Library

    Lurker, Peter

    1998-01-01

    ...) provides many factors needed in the assessment of human health risk that were derived from general population studies or studies involving relatively small groups that may not be representative of military populations...

  9. Particle size: a missing factor in risk assessment of human exposure to toxic chemicals in settled indoor dust.

    Science.gov (United States)

    Cao, Zhi-Guo; Yu, Gang; Chen, Yong-Shan; Cao, Qi-Ming; Fiedler, Heidelore; Deng, Shu-Bo; Huang, Jun; Wang, Bin

    2012-11-15

    For researches on toxic chemicals in settled indoor dust, selection of dust fraction is a critical influencing factor to the accuracy of human exposure risk assessment results. However, analysis of the selection of dust fraction in recent studies revealed that there is no consensus. This study classified and presented researches on distribution of toxic chemicals according to dust particle size and on relationship between dust particle size and human exposure possibility. According to the literature, beyond the fact that there were no consistent conclusions on particle size distribution of adherent fraction, dust with particle size less than 100 μm should be paid more attention and that larger than 250 μm is neither adherent nor proper for human exposure risk assessment. Calculation results based on literature data show that with different selections of dust fractions, analytical results of toxic chemicals would vary up to 10-fold, which means that selecting dust fractions arbitrarily will lead to large errors in risk assessment of human exposure to toxic chemicals in settled dust. Taking into account the influence of dust particle size on risk assessment of human exposure to toxic chemicals, a new methodology for risk assessment of human exposure to toxic chemicals in settled indoor dust is proposed and human exposure parameter systems to settled indoor dust are advised to be established at national and regional scales all over the world. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Digital music exposure reliably induces temporary threshold shift (TTS) in normal hearing human subjects

    Science.gov (United States)

    Le Prell, C. G.; Dell, S.; Hensley, B.; Hall, J. W.; Campbell, K. C. M.; Antonelli, P. J.; Green, G. E.; Miller, J. M.; Guire, K.

    2012-01-01

    Objectives One of the challenges for evaluating new otoprotective agents for potential benefit in human populations is availability of an established clinical paradigm with real world relevance. These studies were explicitly designed to develop a real-world digital music exposure that reliably induces temporary threshold shift (TTS) in normal hearing human subjects. Design Thirty-three subjects participated in studies that measured effects of digital music player use on hearing. Subjects selected either rock or pop music, which was then presented at 93–95 (n=10), 98–100 (n=11), or 100–102 (n=12) dBA in-ear exposure level for a period of four hours. Audiograms and distortion product otoacoustic emissions (DPOAEs) were measured prior to and after music exposure. Post-music tests were initiated 15 min, 1 hr 15 min, 2 hr 15 min, and 3 hr 15 min after the exposure ended. Additional tests were conducted the following day and one week later. Results Changes in thresholds after the lowest level exposure were difficult to distinguish from test-retest variability; however, TTS was reliably detected after higher levels of sound exposure. Changes in audiometric thresholds had a “notch” configuration, with the largest changes observed at 4 kHz (mean=6.3±3.9dB; range=0–13 dB). Recovery was largely complete within the first 4 hours post-exposure, and all subjects showed complete recovery of both thresholds and DPOAE measures when tested 1-week post-exposure. Conclusions These data provide insight into the variability of TTS induced by music player use in a healthy, normal-hearing, young adult population, with music playlist, level, and duration carefully controlled. These data confirm the likelihood of temporary changes in auditory function following digital music player use. Such data are essential for the development of a human clinical trial protocol that provides a highly powered design for evaluating novel therapeutics in human clinical trials. Care must be

  11. Toxicity levels to humans during acute exposure to hydrogen fluoride - An update

    Energy Technology Data Exchange (ETDEWEB)

    Halton, D M

    1995-09-01

    In March 1993, the Atomic Energy Control Board (AECB) commissioned and update of a 1984 review on the acute toxicity of hydrogen fluoride (HF). The study places particular emphasis on the effects of inhalation of gaseous HF and is divided into two main parts: a literature review and a lethal concentration (LC) estimation. The literature review summarizes data under four categories: animal studies, controlled human studies, community exposure, and industrial exposure. Data in these areas were critically reviewed for their relevance to lethal concentrations at LC{sub LO}, LC{sub 10} and LC{sub 50} levels that were derived in the 1984 report. In the last ten years, only one relevant animal study has been published. No new controlled human studies were found but a community exposure incident was reported. There were three new industrial/accidental exposures reported since 1984. Evaluation of new data does not change the lethal concentration estimates made in the 1984 report, but does indicate the absence of appropriate models to estimate the lethality of irritant and corrosive gases. In the last 10 years, much literature on the evaluation of major hazards has been published and suggests that such assessments are of growing political, economic and social importance. Numerous articles have been published on the acute toxicity of HF from skin contact and chronic toxicity from repeated airborne exposure. These publications offer important insights into the nature of HF toxicity. Several avenues of investigative research are suggested. (author). 55 refs., 4 tabs.

  12. Toxicity levels to humans during acute exposure to hydrogen fluoride - An update

    International Nuclear Information System (INIS)

    Halton, D.M.

    1995-09-01

    In March 1993, the Atomic Energy Control Board (AECB) commissioned and update of a 1984 review on the acute toxicity of hydrogen fluoride (HF). The study places particular emphasis on the effects of inhalation of gaseous HF and is divided into two main parts: a literature review and a lethal concentration (LC) estimation. The literature review summarizes data under four categories: animal studies, controlled human studies, community exposure, and industrial exposure. Data in these areas were critically reviewed for their relevance to lethal concentrations at LC LO , LC 10 and LC 50 levels that were derived in the 1984 report. In the last ten years, only one relevant animal study has been published. No new controlled human studies were found but a community exposure incident was reported. There were three new industrial/accidental exposures reported since 1984. Evaluation of new data does not change the lethal concentration estimates made in the 1984 report, but does indicate the absence of appropriate models to estimate the lethality of irritant and corrosive gases. In the last 10 years, much literature on the evaluation of major hazards has been published and suggests that such assessments are of growing political, economic and social importance. Numerous articles have been published on the acute toxicity of HF from skin contact and chronic toxicity from repeated airborne exposure. These publications offer important insights into the nature of HF toxicity. Several avenues of investigative research are suggested. (author). 55 refs., 4 tabs

  13. Concentrations of environmental organic contaminants in meat and meat products and human dietary exposure: A review.

    Science.gov (United States)

    Domingo, José L

    2017-09-01

    Meat and meat products is one of the most relevant food groups in an important number of human diets. Recently, the IARC, based on results of a number of epidemiological studies, classified the consumptions of red meat and processed meat as "probably carcinogenic to humans" and as "carcinogenic to humans", respectively. It was suggested that the substances responsible of the potential carcinogenicity would be mainly generated during meat processing, such as curing and smoking, or when meat is heated at high temperatures. However, the exposure to environmental pollutants through meat consumption was not discussed. The purpose of the present paper was to review recent studies reporting the concentrations of PCDD/Fs, DL-PCBs and PAHs in meat and meat products, as well as the human exposure to these pollutants through the diet. It is concluded that the health risks derived from exposure to carcinogenic environmental contaminants must be considered in the context of each specific diet, which besides meat and meat products, includes other foodstuffs containing also chemical pollutants, some of them with carcinogenic potential. Anyhow, meat and meat products are not the main food group responsible of the dietary exposure to carcinogenic (or probably carcinogenic) environmental organic pollutants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Human exposure to endocrine disrupting chemicals: effects on the male and female reproductive systems.

    Science.gov (United States)

    Sifakis, Stavros; Androutsopoulos, Vasilis P; Tsatsakis, Aristeidis M; Spandidos, Demetrios A

    2017-04-01

    Endocrine disrupting chemicals (EDCs) comprise a group of chemical compounds that have been examined extensively due to the potential harmful effects in the health of human populations. During the past decades, particular focus has been given to the harmful effects of EDCs to the reproductive system. The estimation of human exposure to EDCs can be broadly categorized into occupational and environmental exposure, and has been a major challenge due to the structural diversity of the chemicals that are derived by many different sources at doses below the limit of detection used by conventional methodologies. Animal and in vitro studies have supported the conclusion that endocrine disrupting chemicals affect the hormone dependent pathways responsible for male and female gonadal development, either through direct interaction with hormone receptors or via epigenetic and cell-cycle regulatory modes of action. In human populations, the majority of the studies point towards an association between exposure to EDCs and male and/or female reproduction system disorders, such as infertility, endometriosis, breast cancer, testicular cancer, poor sperm quality and/or function. Despite promising discoveries, a causal relationship between the reproductive disorders and exposure to specific toxicants is yet to be established, due to the complexity of the clinical protocols used, the degree of occupational or environmental exposure, the determination of the variables measured and the sample size of the subjects examined. Future studies should focus on a uniform system of examining human populations with regard to the exposure to specific EDCs and the direct effect on the reproductive system. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Assessment of human exposure to environmental sources of nickel in Europe: Inhalation exposure.

    Science.gov (United States)

    Buekers, Jurgen; De Brouwere, Katleen; Lefebvre, Wouter; Willems, Hanny; Vandenbroele, Marleen; Van Sprang, Patrick; Eliat-Eliat, Maxime; Hicks, Keegan; Schlekat, Christian E; Oller, Adriana R

    2015-07-15

    The paper describes the inhalation nickel (Ni) exposure of humans via the environment for the regional scale in the EU, together with a tiered approach for assessing additional local exposure from industrial emissions. The approach was designed, in the context of REACH, for the purpose of assessing and controlling emissions and air quality in the neighbourhood of Ni producers and downstream users. Two Derived No Effect Level (DNEL) values for chronic inhalation exposure to total Ni in PM10 (20 and 60ngNi/m(3)) were considered. The value of 20ngNi/m(3) is the current EU air quality guidance value. The value of 60ngNi/m(3) is derived here based on recently published Ni data (Oller et al., 2014). Both values are protective for respiratory toxicity and carcinogenicity but differ in the application of toxicokinetic adjustments and cancer threshold considerations. Estimates of air Ni concentrations at the European regional scale were derived from the database of the European Environment Agency. The 50th and 90th percentile regional exposures were below both DNEL values. To assess REACH compliance at the local scale, measured ambient air data are preferred but are often unavailable. A tiered approach for the use of modelled ambient air concentrations was developed, starting with the application of the default EUSES model and progressing to more sophisticated models. As an example, the tiered approach was applied to 33 EU Ni sulphate producers' and downstream users' sites. Applying the EUSES model demonstrates compliance with a DNEL of 60ngNi/m(3) for the majority of sites, while the value of the refined modelling is demonstrated when a DNEL of 20ngNi/m(3) is considered. The proposed approach, applicable to metals in general, can be used in the context of REACH, for refining the risk characterisation and guiding the selection of risk management measures. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Human exploration mission studies

    Science.gov (United States)

    Cataldo, Robert L.

    1989-01-01

    The Office of Exploration has established a process whereby all NASA field centers and other NASA Headquarters offices participate in the formulation and analysis of a wide range of mission strategies. These strategies were manifested into specific scenarios or candidate case studies. The case studies provided a systematic approach into analyzing each mission element. First, each case study must address several major themes and rationale including: national pride and international prestige, advancement of scientific knowledge, a catalyst for technology, economic benefits, space enterprise, international cooperation, and education and excellence. Second, the set of candidate case studies are formulated to encompass the technology requirement limits in the life sciences, launch capabilities, space transfer, automation, and robotics in space operations, power, and propulsion. The first set of reference case studies identify three major strategies: human expeditions, science outposts, and evolutionary expansion. During the past year, four case studies were examined to explore these strategies. The expeditionary missions include the Human Expedition to Phobos and Human Expedition to Mars case studies. The Lunar Observatory and Lunar Outpost to Early Mars Evolution case studies examined the later two strategies. This set of case studies established the framework to perform detailed mission analysis and system engineering to define a host of concepts and requirements for various space systems and advanced technologies. The details of each mission are described and, specifically, the results affecting the advanced technologies required to accomplish each mission scenario are presented.

  17. GLI3 Links Environmental Arsenic Exposure and Human Fetal Growth

    Directory of Open Access Journals (Sweden)

    Emily F. Winterbottom

    2015-06-01

    Full Text Available Although considerable evidence suggests that in utero arsenic exposure affects children's health, these data are mainly from areas of the world where groundwater arsenic levels far exceed the World Health Organization limit of 10 μg/L. We, and others, have found that more common levels of in utero arsenic exposure may also impact children's health. However, the underlying molecular mechanisms are poorly understood. To address this issue, we analyzed the expression of key developmental genes in fetal placenta in a birth cohort of women using unregulated water supplies in a US region with elevated groundwater arsenic. We identified several genes whose expression associated with maternal arsenic exposure in a fetal sex-specific manner. In particular, expression of the HEDGEHOG pathway component, GLI3, in female placentae was both negatively associated with arsenic exposure and positively associated with infant birth weight. This suggests that modulation of GLI3 in the fetal placenta, and perhaps in other fetal tissues, contributes to arsenic's detrimental effects on fetal growth. We showed previously that arsenic-exposed NIH3T3 cells have reduced GLI3 repressor protein. Together, these studies identify GLI3 as a key signaling node that is affected by arsenic, mediating a subset of its effects on developmental signaling and fetal health.

  18. Antiretroviral pre-exposure prophylaxis prevents vaginal transmission of HIV-1 in humanized BLT mice.

    Directory of Open Access Journals (Sweden)

    Paul W Denton

    2008-01-01

    Full Text Available Worldwide, vaginal transmission now accounts for more than half of newly acquired HIV-1 infections. Despite the urgency to develop and implement novel approaches capable of preventing HIV transmission, this process has been hindered by the lack of adequate small animal models for preclinical efficacy and safety testing. Given the importance of this route of transmission, we investigated the susceptibility of humanized mice to intravaginal HIV-1 infection.We show that the female reproductive tract of humanized bone marrow-liver-thymus (BLT mice is reconstituted with human CD4+ T and other relevant human cells, rendering these humanized mice susceptible to intravaginal infection by HIV-1. Effects of HIV-1 infection include CD4+ T cell depletion in gut-associated lymphoid tissue (GALT that closely mimics what is observed in HIV-1-infected humans. We also show that pre-exposure prophylaxis with antiretroviral drugs is a highly effective method for preventing vaginal HIV-1 transmission. Whereas 88% (7/8 of BLT mice inoculated vaginally with HIV-1 became infected, none of the animals (0/5 given pre-exposure prophylaxis of emtricitabine (FTC/tenofovir disoproxil fumarate (TDF showed evidence of infection (Chi square = 7.5, df = 1, p = 0.006.The fact that humanized BLT mice are susceptible to intravaginal infection makes this system an excellent candidate for preclinical evaluation of both microbicides and pre-exposure prophylactic regimens. The utility of humanized mice to study intravaginal HIV-1 transmission is particularly highlighted by the demonstration that pre-exposure prophylaxis can prevent intravaginal HIV-1 transmission in the BLT mouse model.

  19. A Realistic Human Exposure Assessment of Indoor Radon released from Groundwater

    International Nuclear Information System (INIS)

    Yu, Dong Han; Han, Moon Hee

    2002-01-01

    The work presents a realistic human exposure assessment of indoor radon released from groundwater in a house. At first, a two-compartment model is developed to describe the generation and transfer of radon in indoor air from groundwater. The model is used to estimate radon concentrations profile of indoor air in a house using by showering, washing clothes, and flushing toilets. Then, the study performs an uncertainty analysis of model input parameters to quantify the uncertainty in radon concentration profile. In order to estimate a daily internal dose of a specific tissue group in an adult through the inhalation of such indoor radon, a PBPK(Physiologically-Based Pharmaco-Kinetic) model is developed. Combining indoor radon profile and PBPK model is used to a realistic human assessment for such exposure. The results obtained from this study would be used to the evaluation of human risk by inhalation associated with the indoor radon released from groundwater

  20. Development of a ECOREA-II code for human exposures from radionuclides through food chain

    International Nuclear Information System (INIS)

    Yoo, D. H.; Choi, Y. H.

    2001-01-01

    The release of radionuclides from nuclear facilities following an accident into air results in human exposures through two pathways. One is direct human exposures by inhalation or dermal absorption of these radionucles. Another is indirect human exposures through food chain which includes intakes of plant products such as rice, vegetables from contaiminated soil and animal products such as meet, milk and eggs feeded by contaminated grasses or plants on the terrestial surface. This study presents efforts of the development of a computer code for the assessment of the indirect human exposure through such food chains. The purpose of ECOREA-II code is to develop appropriate models suitable for a specific soil condition in Korea based on previous experimental efforts and to provide a more user-friendly environment such as GUI for the use of the code. Therefore, the current code, when more fully developed, is expected to increase the understanding of environmental safety assessment of nuclear facilities following an accident and provide a reasonable regulatory guideline with respecte to food safety issues

  1. Human Exposure Model (HEM): A modular, web-based application to characterize near-field chemical exposures and releases

    Science.gov (United States)

    The U.S. EPA’s Chemical Safety and Sustainability research program is developing the Human Exposure Model (HEM) to assess near-field exposures to chemicals that occur in various populations over the entire life cycle of a consumer product. The model will be implemented as a...

  2. Intermittent, low dose carbon monoxide exposure enhances survival and dopaminergic differentiation of human neural stem cells

    DEFF Research Database (Denmark)

    Dreyer-Andersen, Nanna; Almeida, Ana Sofia; Jensen, Pia

    2018-01-01

    Exploratory studies using human fetal tissue have suggested that intrastriatal transplantation of dopaminergic neurons may become a future treatment for patients with Parkinson's disease. However, the use of human fetal tissue is compromised by ethical, regulatory and practical concerns. Human stem...... cells constitute an alternative source of cells for transplantation in Parkinson's disease, but efficient protocols for controlled dopaminergic differentiation need to be developed. Short-term, low-level carbon monoxide (CO) exposure has been shown to affect signaling in several tissues, resulting...... in Parkinson's disease....

  3. Chronic Exposure to Particulate Nickel Induces Neoplastic Transformation in Human Lung Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Amie L. Holmes

    2013-11-01

    Full Text Available Nickel is a well-known human lung carcinogen with the particulate form being the most potent; however, the carcinogenic mechanism remains largely unknown. Few studies have investigated the genotoxicity and carcinogenicity of nickel in its target cell, human bronchial epithelial cells. Thus, the goal of this study was to investigate the effects of particulate nickel in human lung epithelial cells. We found that nickel subsulfide induced concentration- and time-dependent increases in both cytotoxicity and genotoxicity in human lung epithelial cells (BEP2D. Chronic exposure to nickel subsulfide readily induced cellular transformation, inducing 2.55, 2.9 and 2.35 foci per dish after exposure to 1, 2.5 and 5 μg/cm2 nickel subsulfide, respectively. Sixty-one, 100 and 70 percent of the foci isolated from 1, 2.5, and 5 μg/cm2 nickel subsulfide treatments formed colonies in soft agar and the degree of soft agar colony growth increased in a concentration-dependent manner. Thus, chronic exposure to particulate nickel induces genotoxicity and cellular transformation in human lung epithelial cells.

  4. Human exposure to ionizing radiation for medical reasons

    International Nuclear Information System (INIS)

    Thomas, R.H.; Busick, D.D.

    1977-01-01

    The central issue in this debate is not whether there is a threshold dose below which deleterious effects in humans occur nor whether the dose-effect relationship is linear or curvilinear. The central issue is whether there is merit in a continuing effort to reduce radiation exposures to patients no matter at what level. This should be determined by a careful balancing of potential risks against expected benefits. It is this element of risk-benefit analysis that is absent in Morgan's philosophy. A good example of the changing nature on the risk-benefit balance is that of the use of mass radiography programs to diagnose tuberculosis. Before the Second World War this disease was a terrible scourge of the poor who could ill-afford adequate medical care. The use of mass radiography programs have played a large part in the elimination of this disease

  5. A model of human nasal epithelial cells adapted for direct and repeated exposure to airborne pollutants.

    Science.gov (United States)

    Bardet, Gaëlle; Achard, Sophie; Loret, Thomas; Desauziers, Valérie; Momas, Isabelle; Seta, Nathalie

    2014-08-17

    Airway epithelium lining the nasal cavity plays a pivotal role in respiratory tract defense and protection mechanisms. Air pollution induces alterations linked to airway diseases such as asthma. Only very few in vitro studies to date have succeeded in reproducing physiological conditions relevant to cellular type and chronic atmospheric pollution exposure. We therefore, set up an in vitro model of human Airway Epithelial Cells of Nasal origin (hAECN) close to real human cell functionality, specifically adapted to study the biological effects of exposure to indoor gaseous pollution at the environmental level. hAECN were exposed under air-liquid interface, one, two, or three-times at 24 h intervals for 1 h, to air or formaldehyde (200 μg/m(3)), an indoor air gaseous pollutant. All experiments were ended at day 4, when both cellular viability and cytokine production were assessed. Optimal adherence and confluence of cells were obtained 96 h after cell seeding onto collagen IV-precoated insert. Direct and repeated exposure to formaldehyde did not produce any cellular damage or IL-6 production change, although weak lower IL-8 production was observed only after the third exposure. Our model is significantly better than previous ones due to cell type and the repeated exposure protocol. Copyright © 2014. Published by Elsevier Ireland Ltd.

  6. Alcohol, Methamphetamine, and Marijuana Exposure Have Distinct Effects on the Human Placenta.

    Science.gov (United States)

    Carter, R Colin; Wainwright, Helen; Molteno, Christopher D; Georgieff, Michael K; Dodge, Neil C; Warton, Fleur; Meintjes, Ernesta M; Jacobson, Joseph L; Jacobson, Sandra W

    2016-04-01

    Animal studies have demonstrated adverse effects of prenatal alcohol exposure on placental development, but few studies have examined these effects in humans. Little is known about effects of prenatal exposure to methamphetamine, marijuana, and cigarette smoking on placental development. Placentas were collected from 103 Cape Coloured (mixed ancestry) pregnant women recruited at their first antenatal clinic visit in Cape Town, South Africa. Sixty-six heavy drinkers and 37 nondrinkers were interviewed about their alcohol, cigarette smoking, and drug use at 3 antenatal visits. A senior pathologist, blinded to exposure status, performed comprehensive pathology examinations on each placenta using a standardized protocol. In multivariable regression models, effects of prenatal exposure were examined on placental size, structure, and presence of infections and meconium. Drinkers reported a binge pattern of heavy drinking, averaging 8.0 drinks/occasion across pregnancy on 1.4 d/wk. 79.6% smoked cigarettes; 22.3% used marijuana; and 17.5% used methamphetamine. Alcohol exposure was related to decreased placental weight and a smaller placenta-to-birthweight ratio. By contrast, methamphetamine was associated with larger placental weight and a larger placenta-to-birthweight ratio. Marijuana was also associated with larger placental weight. Alcohol exposure was associated with increased risk of placental hemorrhage. Prenatal alcohol, drug, and cigarette use were not associated with chorioamnionitis, villitis, deciduitis, or maternal vascular underperfusion. Alcohol and cigarette smoking were associated with a decreased risk of intrauterine passing of meconium, a sign of acute fetal stress and/or hypoxia; methamphetamine, with an increased risk. This is the first human study to show that alcohol, methamphetamine, and marijuana were associated with distinct patterns of pathology, suggesting different mechanisms mediating their effects on placental development. Given the growing

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

    Science.gov (United States)

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

    2015-01-01

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

  8. Risk Communication in EPA's Controlled Inhalation Exposure Studies and in Support.

    Science.gov (United States)

    Resnik, David

    2017-01-01

    On March 28, 2017, the National Academy of Sciences, Engineering, and Medicine (NASEM) released a much-anticipated report on the Environmental Protection Agency's controlled human inhalation exposure studies. This essay reviews the ethical controversies that led to the genesis of the report, summarizes its key findings, and comments on its approach to informing human subjects about the risks of inhalation exposure studies. NASEM's report makes a valuable contribution to our understanding of the scientific and ethical issues involved in conducting human inhalation exposure studies. Its definition of "reasonably foreseeable risks" provides useful guidance to investigators, research participants, and institutional review board members.

  9. Lead Exposure Induces Telomere Instability in Human Cells.

    Directory of Open Access Journals (Sweden)

    Géraldine Pottier

    Full Text Available Lead (Pb is an important environmental contaminant due to its widespread use over many centuries. While it affects primarily every organ system of the body, the most pernicious effects of Pb are on the central nervous system leading to cognitive and behavioral modification. Despite decades of research, the mechanisms responsible for Pb toxicity remain poorly understood. Recent work has suggested that Pb exposure may have consequences on chromosomal integrity as it was shown that Pb exposure leads to the generation of γH2Ax foci, a well-established biomarker for DNA double stranded break (DSB formation. As the chromosomal localization of γH2Ax foci plays an important role in determining the molecular mechanism responsible for their formation, we examined the localization of Pb-induced foci with respect to telomeres. Indeed, short or dysfunctional telomeres (uncapped or damaged telomeres may be recognized as DSB by the DNA repair machinery, leading to "telomere-Induced Foci" (TIFs. In the current study, we show that while Pb exposure did not increase intra-chromosomal foci, it significantly induced TIFs, leading in some cases, to chromosomal abnormalities including telomere loss. The evidence suggests that these chromosomal abnormalities are likely due to perturbation of telomere replication, in particular on the lagging DNA strand. We propose a mechanism by which Pb exposure leads to the loss of telomere maintenance. As numerous studies have demonstrated a role for telomere maintenance in brain development and tissue homeostasis, our results suggest a possible mechanism for lead-induced neurotoxicity.

  10. Exposure to ozone modulates human airway protease/antiprotease balance contributing to increased influenza A infection.

    Directory of Open Access Journals (Sweden)

    Matthew J Kesic

    Full Text Available Exposure to oxidant air pollution is associated with increased respiratory morbidities and susceptibility to infections. Ozone is a commonly encountered oxidant air pollutant, yet its effects on influenza infections in humans are not known. The greater Mexico City area was the primary site for the spring 2009 influenza A H1N1 pandemic, which also coincided with high levels of environmental ozone. Proteolytic cleavage of the viral membrane protein hemagglutinin (HA is essential for influenza virus infectivity. Recent studies suggest that HA cleavage might be cell-associated and facilitated by the type II transmembrane serine proteases (TTSPs human airway trypsin-like protease (HAT and transmembrane protease, serine 2 (TMPRSS2, whose activities are regulated by antiproteases, such as secretory leukocyte protease inhibitor (SLPI. Based on these observations, we sought to determine how acute exposure to ozone may modulate cellular protease/antiprotease expression and function, and to define their roles in a viral infection. We utilized our in vitro model of differentiated human nasal epithelial cells (NECs to determine the effects of ozone on influenza cleavage, entry, and replication. We show that ozone exposure disrupts the protease/antiprotease balance within the airway liquid. We also determined that functional forms of HAT, TMPRSS2, and SLPI are secreted from human airway epithelium, and acute exposure to ozone inversely alters their expression levels. We also show that addition of antioxidants significantly reduces virus replication through the induction of SLPI. In addition, we determined that ozone-induced cleavage of the viral HA protein is not cell-associated and that secreted endogenous proteases are sufficient to activate HA leading to a significant increase in viral replication. Our data indicate that pre-exposure to ozone disrupts the protease/antiprotease balance found in the human airway, leading to increased influenza susceptibility.

  11. Human biomonitoring pilot study DEMOCOPHES in Germany

    DEFF Research Database (Denmark)

    Schwedler, Gerda; Seiwert, Margarete; Fiddicke, Ulrike

    2017-01-01

    , cadmium, cotinine and several phthalate metabolites in urine of 6–11 year old children and their mothers in an urban and a rural region. Seventeen European countries simultaneously conducted this cross-sectional DEMOCOPHES feasibility study. The German study population was taken in the city of Bochum...... and in the Higher Sauerland District, comprising 120 mother-child pairs. In the present paper features of the study implementation are presented. German exposure concentrations of the pollutants are reported and compared with European average concentrations from DEMOCOPHES and with those measured......Human biomonitoring (HBM) is an effective tool to assess human exposure to environmental pollutants, but comparable HBM data in Europe are lacking. In order to expedite harmonization of HBM studies on a European scale, the twin projects COPHES (Consortium to Perform Human Biomonitoring...

  12. Modelling ecological and human exposure to POPs in Venice lagoon - Part II: Quantitative uncertainty and sensitivity analysis in coupled exposure models.

    Science.gov (United States)

    Radomyski, Artur; Giubilato, Elisa; Ciffroy, Philippe; Critto, Andrea; Brochot, Céline; Marcomini, Antonio

    2016-11-01

    The study is focused on applying uncertainty and sensitivity analysis to support the application and evaluation of large exposure models where a significant number of parameters and complex exposure scenarios might be involved. The recently developed MERLIN-Expo exposure modelling tool was applied to probabilistically assess the ecological and human exposure to PCB 126 and 2,3,7,8-TCDD in the Venice lagoon (Italy). The 'Phytoplankton', 'Aquatic Invertebrate', 'Fish', 'Human intake' and PBPK models available in MERLIN-Expo library were integrated to create a specific food web to dynamically simulate bioaccumulation in various aquatic species and in the human body over individual lifetimes from 1932 until 1998. MERLIN-Expo is a high tier exposure modelling tool allowing propagation of uncertainty on the model predictions through Monte Carlo simulation. Uncertainty in model output can be further apportioned between parameters by applying built-in sensitivity analysis tools. In this study, uncertainty has been extensively addressed in the distribution functions to describe the data input and the effect on model results by applying sensitivity analysis techniques (screening Morris method, regression analysis, and variance-based method EFAST). In the exposure scenario developed for the Lagoon of Venice, the concentrations of 2,3,7,8-TCDD and PCB 126 in human blood turned out to be mainly influenced by a combination of parameters (half-lives of the chemicals, body weight variability, lipid fraction, food assimilation efficiency), physiological processes (uptake/elimination rates), environmental exposure concentrations (sediment, water, food) and eating behaviours (amount of food eaten). In conclusion, this case study demonstrated feasibility of MERLIN-Expo to be successfully employed in integrated, high tier exposure assessment. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Exposure to CB-153 and p,p'-DDE and human sperm chromatin integrity

    Energy Technology Data Exchange (ETDEWEB)

    Rignell-Hydbom, A; Rylander, L; Joensson, B A.G.; Hagmar, L [Dept. of Occupational and Environmental Medicine, Lund Univ. Hospital (Sweden); Giwercman, A [Fertility Centre, Malmoe Univ. hospital (Sweden); Spano, M [Section of Toxicology and Biomedical Sciences, ENEA Casaccia Research Centre, Rome (Italy)

    2004-09-15

    In Sweden, the consumption of fatty fish from the Baltic Sea (off the Swedish east coast) is the single most important source of exposure to persistent organochlorine pollutants (POPs). Fishermen from the east coast have averagely higher plasma levels of polychlorinated biphenyls (PCBs) and total POP derived TEQ in plasma than both west coast fishermen and men from the general population. Dichlorodiphenyl dichloroethene (p,p'-DDE), a relevant biomarker for POP is still present in relatively high serum concentrations in men consuming fish from the Baltic Sea. Several studies have shown that POPs are capable of interfering with reproductive and endocrine function in animals. Human studies have shown that exposure to PCBs and polychlorinated dibenzofurans (PCDFs) has a negative effect on male reproductive function, and especially sperm motility seems vulnerable. However, studies relating to human sperm genetic integrity are few. The aim of the study was to investigate whether exposure to POP using 2,2',4,4',5,5'- hexachlorobiphenyl (CB-153) and p,p'-DDE as biomarkers, are associated with sperm chromatin integrity. In order to ensure a sufficient variation in POP exposure fishermen from both the Swedish east (''more exposed'') and west coasts (''less exposed'') formed the study base.

  14. Exposure to CB-153 and p,p'-DDE and human sperm chromatin integrity

    Energy Technology Data Exchange (ETDEWEB)

    Rignell-Hydbom, A.; Rylander, L.; Joensson, B.A.G.; Hagmar, L. [Dept. of Occupational and Environmental Medicine, Lund Univ. Hospital (Sweden); Giwercman, A. [Fertility Centre, Malmoe Univ. hospital (Sweden); Spano, M. [Section of Toxicology and Biomedical Sciences, ENEA Casaccia Research Centre, Rome (Italy)

    2004-09-15

    In Sweden, the consumption of fatty fish from the Baltic Sea (off the Swedish east coast) is the single most important source of exposure to persistent organochlorine pollutants (POPs). Fishermen from the east coast have averagely higher plasma levels of polychlorinated biphenyls (PCBs) and total POP derived TEQ in plasma than both west coast fishermen and men from the general population. Dichlorodiphenyl dichloroethene (p,p'-DDE), a relevant biomarker for POP is still present in relatively high serum concentrations in men consuming fish from the Baltic Sea. Several studies have shown that POPs are capable of interfering with reproductive and endocrine function in animals. Human studies have shown that exposure to PCBs and polychlorinated dibenzofurans (PCDFs) has a negative effect on male reproductive function, and especially sperm motility seems vulnerable. However, studies relating to human sperm genetic integrity are few. The aim of the study was to investigate whether exposure to POP using 2,2',4,4',5,5'- hexachlorobiphenyl (CB-153) and p,p'-DDE as biomarkers, are associated with sperm chromatin integrity. In order to ensure a sufficient variation in POP exposure fishermen from both the Swedish east (''more exposed'') and west coasts (''less exposed'') formed the study base.

  15. Using Information on Exposure to Characterizing Risks to Human Health from Concurrent Exposures to Multiple Chemicals

    NARCIS (Netherlands)

    Mr Price, PSP

    2012-01-01

    This thesis explores the concept of using exposure information to understand, organize, and manage the risks associated with cumulative exposures to chemicals (exposures to multiple chemicals from multiple sources). The issue of cumulative exposures was identified in more than 30 years ago, but in

  16. Weighing serological evidence of human exposure to animal influenza viruses - a literature review.

    Science.gov (United States)

    Sikkema, Reina Saapke; Freidl, Gudrun Stephanie; de Bruin, Erwin; Koopmans, Marion

    2016-11-03

    Assessing influenza A virus strains circulating in animals and their potential to cross the species barrier and cause human infections is important to improve human influenza surveillance and preparedness. We reviewed studies describing serological evidence of human exposure to animal influenza viruses. Comparing serological data is difficult due to a lack of standardisation in study designs and in laboratory methods used in published reports. Therefore, we designed a scoring system to assess and weigh specificity of obtained serology results in the selected articles. Many studies report reliable evidence of antibodies to swine influenza viruses among persons occupationally exposed to pigs. Most avian influenza studies target H5, H7 and H9 subtypes and most serological evidence of human exposure to avian influenza viruses is reported for these subtypes. Avian influenza studies receiving a low grade in this review often reported higher seroprevalences in humans compared with studies with a high grade. Official surveillance systems mainly focus on avian H5 and H7 viruses. Swine influenza viruses and avian subtypes other than H5 and H7 (emphasising H9) should be additionally included in official surveillance systems. Surveillance efforts should also be directed towards understudied geographical areas, such as Africa and South America. This article is copyright of The Authors, 2016.

  17. Weighing serological evidence of human exposure to animal influenza viruses − a literature review

    Science.gov (United States)

    Sikkema, Reina Saapke; Freidl, Gudrun Stephanie; de Bruin, Erwin; Koopmans, Marion

    2016-01-01

    Assessing influenza A virus strains circulating in animals and their potential to cross the species barrier and cause human infections is important to improve human influenza surveillance and preparedness. We reviewed studies describing serological evidence of human exposure to animal influenza viruses. Comparing serological data is difficult due to a lack of standardisation in study designs and in laboratory methods used in published reports. Therefore, we designed a scoring system to assess and weigh specificity of obtained serology results in the selected articles. Many studies report reliable evidence of antibodies to swine influenza viruses among persons occupationally exposed to pigs. Most avian influenza studies target H5, H7 and H9 subtypes and most serological evidence of human exposure to avian influenza viruses is reported for these subtypes. Avian influenza studies receiving a low grade in this review often reported higher seroprevalences in humans compared with studies with a high grade. Official surveillance systems mainly focus on avian H5 and H7 viruses. Swine influenza viruses and avian subtypes other than H5 and H7 (emphasising H9) should be additionally included in official surveillance systems. Surveillance efforts should also be directed towards understudied geographical areas, such as Africa and South America. PMID:27874827

  18. Long-term human exposure to lead from different media and intake pathways.

    Science.gov (United States)

    Pizzol, Massimo; Thomsen, Marianne; Andersen, Mikael Skou

    2010-10-15

    Lead (Pb) is well known as an environmental pollutant: it can accumulate in various media, so actual lead exposure reflects both historical and present contaminations. Two main challenges then emerge: obtaining updated information to gain an overall picture of the sources of exposure, and predicting the resulting internal body exposure levels and effects that occur under long-term exposure conditions. In this paper, a modeling approach is used to meet these challenges with reference to Danish exposure conditions. Levels of lead content in various media have been coupled with data for lead intake and absorption in the human body, for both children and adults. An age-dependent biokinetic model allows then for determination of the blood lead levels resulting from chronic exposure. The study shows that the actual intake of lead is up to 27% of the Provisional Tolerable Daily Intake (PTDI) for children and around 8% for adults. It is confirmed that the critical route of exposure is via ingestion, accounting for 99% of total lead intake, while inhalation contributes only to 1% of total lead intake. The resulting lead levels in the blood after 2 years of exposure to actual contamination conditions have been estimated as up to 2.2μg/dl in children and almost 1μg/dl in adults. Impacts from lead can occur even at such levels. The role of historical and present sources to lead in the environment is discussed, and, for specific child and adult exposure scenarios, external-internal concentration relationships for the direct linkage between lead in environmental media and resulting concentrations of lead in blood are then presented. Copyright © 2010 Elsevier B.V. All rights reserved.

  19. Estimating the human exposure to chemical substances and radiation. Definition report

    International Nuclear Information System (INIS)

    Vermeire, T.G.; Van Veen, M.P.

    1995-06-01

    This report aims at boosting the human exposure assessment activities of the RIVM with regard to chemical substances and radiation. It is the result of thorough discussions with RIVM-experts. The report starts with an overview of past developments in the area of human exposure assessment at the RIVM and continues describing recent projects. Major developments outside the Institute are also discussed. An attempt is made to harmonize definitions which are relevant for exposure assessment, i.e. definitions on exposure, intake, uptake and dose. Important gaps in the human exposure assessment work at the RIVM are identified, leading to proposals for future work. 2 figs., 31 refs., 3 appendices

  20. The recovery of the human organism after radiation exposure

    International Nuclear Information System (INIS)

    Gerber, G.B.

    1976-01-01

    The repair of radiation damage in the human organism is reviewed. A distinction is made between the single repair steps, first the molecular repair of sublethal damage during the periods of 30 min to 2 h and several days to months, second the substitution of the whole cells during a period of reproduction which is specific for the kind and persistence of the cells. One example is the radiosensitive stem cell with a reproduction rate of 40% and a redoublication time of 10 d at 100 rads and the very low reproduction rate of 1% with redoublication time of 7 d after a dose of 400 rads. 5 rads seems to be acceptable for systems with recovery and repeated exposure, single doses normally should not exceed 25 rads, not 100 rads/d for to save human life, and not a total dose of 500 rads. About 20% of irradiation damage is not repaired and leads to late effects, for example the induction of tumors, the shortening of life span and an increase in embryonic mortality. The author recommends the acceptance of a radiation dose leading to 20 additional cases of leucemia in the whole population of Germany and an increase of tumor frequency of 1%. The shortening of life span should not exceed 0,5%. The equivalent residual dose (ERD) can be calculated by the following equation: ERD = last effective dose minus 5 rads x number of days. (AJ) [de

  1. Digital music exposure reliably induces temporary threshold shift in normal-hearing human subjects.

    Science.gov (United States)

    Le Prell, Colleen G; Dell, Shawna; Hensley, Brittany; Hall, James W; Campbell, Kathleen C M; Antonelli, Patrick J; Green, Glenn E; Miller, James M; Guire, Kenneth

    2012-01-01

    One of the challenges for evaluating new otoprotective agents for potential benefit in human populations is the availability of an established clinical paradigm with real-world relevance. These studies were explicitly designed to develop a real-world digital music exposure that reliably induces temporary threshold shift (TTS) in normal-hearing human subjects. Thirty-three subjects participated in studies that measured effects of digital music player use on hearing. Subjects selected either rock or pop music, which was then presented at 93 to 95 (n = 10), 98 to 100 (n = 11), or 100 to 102 (n = 12) dBA in-ear exposure level for a period of 4 hr. Audiograms and distortion product otoacoustic emissions (DPOAEs) were measured before and after music exposure. Postmusic tests were initiated 15 min, 1 hr 15 min, 2 hr 15 min, and 3 hr 15 min after the exposure ended. Additional tests were conducted the following day and 1 week later. Changes in thresholds after the lowest-level exposure were difficult to distinguish from test-retest variability; however, TTS was reliably detected after higher levels of sound exposure. Changes in audiometric thresholds had a "notch" configuration, with the largest changes observed at 4 kHz (mean = 6.3 ± 3.9 dB; range = 0-14 dB). Recovery was largely complete within the first 4 hr postexposure, and all subjects showed complete recovery of both thresholds and DPOAE measures when tested 1 week postexposure. These data provide insight into the variability of TTS induced by music-player use in a healthy, normal-hearing, young adult population, with music playlist, level, and duration carefully controlled. These data confirm the likelihood of temporary changes in auditory function after digital music-player use. Such data are essential for the development of a human clinical trial protocol that provides a highly powered design for evaluating novel therapeutics in human clinical trials. Care must be taken to fully inform potential subjects in

  2. Novel Human Radiation Exposure Biomarker Panel Applicable for Population Triage

    Energy Technology Data Exchange (ETDEWEB)

    Bazan, Jose G. [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Chang, Polly; Balog, Robert; D' Andrea, Annalisa; Shaler, Thomas; Lin, Hua; Lee, Shirley; Harrison, Travis [SRI International, Menlo Park, California (United States); Shura, Lei; Schoen, Lucy; Knox, Susan J. [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Cooper, David E., E-mail: david.cooper@sri.com [SRI International, Menlo Park, California (United States)

    2014-11-01

    Purpose: To identify a panel of radiation-responsive plasma proteins that could be used in a point-of-care biologic dosimeter to detect clinically significant levels of ionizing radiation exposure. Methods and Materials: Patients undergoing preparation for hematopoietic cell transplantation using radiation therapy (RT) with either total lymphoid irradiation or fractionated total body irradiation were eligible. Plasma was examined from patients with potentially confounding conditions and from normal individuals. Each plasma sample was analyzed for a panel of 17 proteins before RT was begun and at several time points after RT exposure. Paired and unpaired t tests between the dose and control groups were performed. Conditional inference trees were constructed based on panels of proteins to compare the non-RT group with the RT group. Results: A total of 151 patients (62 RT, 41 infection, 48 trauma) were enrolled on the study, and the plasma from an additional 24 healthy control individuals was analyzed. In comparison with to control individuals, tenascin-C was upregulated and clusterin was downregulated in patients receiving RT. Salivary amylase was strongly radiation responsive, with upregulation in total body irradiation patients and slight downregulation in total lymphoid irradiation patients compared with control individuals. A panel consisting of these 3 proteins accurately distinguished between irradiated patients and healthy control individuals within 3 days after exposure: 97% accuracy, 0.5% false negative rate, 2% false positive rate. The accuracy was diminished when patients with trauma, infection, or both were included (accuracy, 74%-84%; false positive rate, 14%-33%, false negative rate: 8%-40%). Conclusions: A panel of 3 proteins accurately distinguishes unirradiated healthy donors from those exposed to RT (0.8-9.6 Gy) within 3 days of exposure. These findings have significant implications in terms of triaging individuals in the case of nuclear or other

  3. Effect of Exposure to Non-ionizing Radiation (Electromagnetic Fields on Human System: A Literature Review

    Directory of Open Access Journals (Sweden)

    Paula Rubya Souza C and acirc;mara

    2014-08-01

    Full Text Available The indiscriminate presence of radio base stations, which emit non-ionizing radiation (NIR, as well as the frequent use of mobile phones, can cause increased susceptibility of populations to the emergence of diseases such as cancers of the head and neck, biochemical, hematopoietic and hepatic changes, among others. Exposure to physical contamination, including NIR, has been implicated in numerous diseases, raising concerns about the widespread sources of exposure to this type of radiation. This paper reviews studies that have assessed associations between likely exposure to electromagnetic fields, such as radiofrequency transmissions, and many kinds of human diseases including cancer, as well as alerts to the current knowledge on the association between environmental exposure to NIR and the risk of development of adverse human health effects. This way, there appears to be an urgent need to reconsider exposure limits for low frequency and static magnetic fields, based on combined experimental and epidemiological research. [J Interdiscipl Histopathol 2014; 2(4.000: 187-190

  4. Studies of effects of radiation exposure on children

    International Nuclear Information System (INIS)

    Kakinuma, Shizuko; Imaoka, Tatsuhiko; Nishimura, Mayumi; Shimada, Yoshiya

    2014-01-01

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

  5. Assessment of genetic risk for human exposure to radiation. State of the art

    International Nuclear Information System (INIS)

    Shevchenko, V.A.

    2000-01-01

    Historical aspects of the conception of genetic risk of human irradiation for recent 40 years. Methodology of assessing the genetic risk of radiation exposure is based on the concept of hitting the target. To predict genetic risk of irradiation, the direct and indirect methods of assessment, extrapolation, integral and populational criteria of risk analysis is widely used. Combination of these methods permits to calculate the risk from human exposure on the basis of data obtained for mice. Method of doubling dose based on determination of the dose doubling the level of natural mutational process in humans is the main one used to predict the genetic risk. Till 1972 the main model for assessing the genetic risk was the human/mouse model (the use of data on the spontaneous human variability and data on the frequency of induced mutations in mice). In the period from 1972 till 1994 the mouse/mouse model was intensively elaborated in many laboratories. This model was also used in this period to analyse the genetic risk of human irradiation. Recent achievements associated with the study of molecular nature of many hereditary human diseases as well as the criticism of a fundamental principles of the mouse/mouse model for estimating the genetic risk on a new basis. Estimates of risk for the different classes of genetic diseases have been obtained using the doubling-dose method [ru

  6. INFLUENCE OF EXPOSURE ASSESSMENT METHOD IN AN EPIDEMIOLOGIC STUDY OF TRIHALOMETHANE EXPOSURE AND SPONTANEOUS ABORTION

    Science.gov (United States)

    Trihalomethanes are common contaminants of chlorinated drinking water. Studies of their health effects have been hampered by exposure misclassification, due in part to limitations inherent in using utility sampling records. We used two exposure assessment methods, one based on ut...

  7. Human exposure assessment to antibiotic-resistant Escherichia coli through drinking water.

    Science.gov (United States)

    O'Flaherty, E; Borrego, C M; Balcázar, J L; Cummins, E

    2018-03-01

    Antibiotic-resistant bacteria (ARB) are a potential threat to human health through drinking water with strong evidence of ARB presence in post treated tap water around the world. This study examines potential human exposure to antibiotic-resistant (AR) Escherichia coli (E. coli) through drinking water, the effect of different drinking water treatments on AR E. coli and the concentration of AR E. coli required in the source water for the EU Drinking Water Directive (DWD) (Council Directive 98/83/EC, 0CFU/100ml of E. coli in drinking water) to be exceeded. A number of scenarios were evaluated to examine different water treatment combinations and to reflect site specific conditions at a study site in Europe. A literature search was carried out to collate data on the effect of environmental conditions on AR E. coli, the effect of different water treatments on AR E. coli and typical human consumption levels of tap water. A human exposure assessment model was developed with probability distributions used to characterise uncertainty and variability in the input data. Overall results show the mean adult human exposure to AR E. coli from tap water consumption ranged between 3.44×10 -7 and 2.95×10 -1 cfu/day for the scenarios tested and varied depending on the water treatments used. The level of AR E. coli required in the source water pre-treatment to exceed the DWD varied between 1 and 5logcfu/ml, depending on the water treatments used. This can be used to set possible monitoring criteria in pre-treated water for potential ARB exposure in drinking water. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Mobile phone radiofrequency exposure has no effect on DNA double strand breaks (DSB) in human lymphocytes.

    Science.gov (United States)

    Danese, Elisa; Lippi, Giuseppe; Buonocore, Ruggero; Benati, Marco; Bovo, Chiara; Bonaguri, Chiara; Salvagno, Gian Luca; Brocco, Giorgio; Roggenbuck, Dirk; Montagnana, Martina

    2017-07-01

    The use of mobile phones has been associated with an increased risk of developing certain type of cancer, especially in long term users. Therefore, this study was aimed to investigate the potential genotoxic effect of mobile phone radiofrequency exposure on human peripheral blood mononuclear cells in vitro. The study population consisted in 14 healthy volunteers. After collection of two whole blood samples, the former was placed in a plastic rack, 1 cm from the chassis of a commercial mobile phone (900 MHz carrier frequency), which was activated by a 30-min call. The second blood sample was instead maintained far from mobile phones or other RF sources. The influence of mobile phone RF on DNA integrity was assessed by analyzing γ-H2AX foci in lymphocytes using immunofluorescence staining kit on AKLIDES. No measure of γ-H2AX foci was significantly influenced by mobile phone RF exposure, nor mobile phone exposure was associated with significant risk of genetic damages in vitro (odds ratio comprised between 0.27 and 1.00). The results of this experimental study demonstrate that exposure of human lymphocytes to a conventional 900 MHz RF emitted by a commercial mobile phone for 30 min does not significantly impact DNA integrity.

  9. European studies on occupational radiation exposure - ESOREX

    International Nuclear Information System (INIS)

    Petrova, K.; Frasch, G.

    2005-01-01

    Full text: The ESOREX project was initiated by the European Commission in 1997. The objectives of this European study are: to provide the European Commission and the national competent radiation protection authorities with reliable information on how personal radiation monitoring, reporting and recording of dosimetric results is organized in European countries; to collect reliable and directly comparable data on individual and collective radiation exposure in all occupational sectors where radiation workers are employed. The information about the monitoring of occupational radiation exposure, the levels of individual personal doses of workers in the different work sectors, the changes and trends of these doses over a period of several years and the international comparison of these data are useful information for many stakeholders. The survey consists of two parts. Part I surveys how radiation protection monitoring, recording and reporting is arranged within each of the 30 European countries. Part II collects doses from occupational exposure of classified workers in the participating countries. For each country, information is provided on the number of workers in defined work categories and how annual individual personal doses are distributed. The summary and the conclusions provide tentative recommendations for harmonizing modifications of some of the national monitoring, reporting and recording arrangements. In all ESOREX studies a beneficial, effective and extensive information base about thirty European states has been created. The studies resulted in country reports describing the legislative, administrative, organizational and technical aspects of the national dose monitoring and recording systems for occupationally radiation exposed workers. These reports are standardized, i.e. they have as far as possible an internationally comparable structure. The dose distributions of the radiation workers and the annual average and collective doses in the various work

  10. Considering human exposure to pesticides in food products: Importance of dissipation dynamics

    DEFF Research Database (Denmark)

    Fantke, Peter; Juraske, Ronnie; Jolliet, Olivier

    2014-01-01

    The general public is continuously concerned about effects from pesticide exposure via residues in food crops. However, impacts from pesticide exposure are mostly neglected in food product-related LCAs. Time-to-harvest and dissipation from crops mainly drive residue dynamics with dissipation...... as most uncertain aspect in characterization modeling. We analyzed measured half-lives (n=4513) with 95% falling between 0.6 and 29 days. With ~500 pesticides authorized alone in the EU for several hundred crops, however, experimental stud-ies only cover few possible pesticide-crop combinations. Therefore......, we estimated dissipation from measured data and provide reference half-lives for 333 pesticides applied at 20°C under field conditions. Our framework allows for detailed explorations of dietary choices in LCA with respect to human health impacts from pesticide exposure via crop consumption. The next...

  11. ASSESSING HUMAN EXPOSURE TO GRASS POLLEN IN DENMARK

    DEFF Research Database (Denmark)

    Peel, Robert George; Hertel, Ole; Herbert, Rob

    Objectives: Exposure to pollen is typically assessed using data collected at fixed roof-top monitoring stations, which give a general picture of airborne pollen concentrations over a wide region. Actual exposure levels can be obtained through personal exposure monitoring. This is typically done u...

  12. Human Bronchial Epithelial Cell Response to Heavy Particle Exposure

    Science.gov (United States)

    Story, Michael; Ding, Liang-Hao; Minna, John; Park, Seong-mi; Peyton, Michael; Larsen, Jill

    2012-07-01

    A battery of non-oncogenically immortalized human bronchial epithelial cells (HBECs) are being used to examine the molecular changes that lead to lung carcinogenesis after exposure to heavy particles found in the free space environment. The goal is to ultimately identify biomarkers of radioresponse that can be used for prediction of carcinogenic risk for fatal lung cancer. Our initial studies have focused on the cell line HBEC3 KT and the isogenic variant HBEC3 KTR53, which overexpresses the RASv12 mutant and where p53 has been knocked down by shRNA, and is considered to be a more oncogenically progressed variant. We have previously described the response of HBEC3 KT at the cellular and molecular level, however, the focus here is on the rate of cellular transformation after HZE radiation exposure and the molecular changes in transformed cells. When comparing the two cell lines we find that there is a maximum rate of cellular transformation at 0.25 Gy when cells are exposed to 1 GeV Fe particles, and, for the HBEC3 KTR53 there are multiple pathways upregulated that promote anchorage independent growth including the mTOR pathway, the TGF-1 pathway, RhoA signaling and the ERK/MAPK pathway as early as 2 weeks after radiation. This does not occur in the HBEC3 KT cell line. Transformed HBEC3 KT cells do not show any morphologic or phenotypic changes when grown as cell cultures. HBEC3 KTR53 cells on the other hand show substantial changes in morphology from a cobblestone epithelial appearance to a mesenchymal appearance with a lack of contact inhibition. This epithelial to mesenchymal change in morphology is accompanied by the expression of vimentin and a reduction in the expression of E-cadherin, which are hallmarks of epithelial to mesenchymal transition. Interestingly, for HBEC3 KT transformed cells there are no mutations in the p53 gene, 2 of 15 clones were found to be heterozygous for the RASV12 mutation, and 3 of 15 clones expressed high levels of BigH3, a TGFB

  13. Environmental exposure to human carcinogens in teenagers and the association with DNA damage

    International Nuclear Information System (INIS)

    Franken, Carmen; Koppen, Gudrun; Lambrechts, Nathalie; Govarts, Eva; Bruckers, Liesbeth; Den Hond, Elly; Loots, Ilse; Nelen, Vera; Sioen, Isabelle; Nawrot, Tim S.; Baeyens, Willy; Van Larebeke, Nicolas; Boonen, Francis; Ooms, Daniëlla; Wevers, Mai; Jacobs, Griet; Covaci, Adrian; Schettgen, Thomas; Schoeters, Greet

    2017-01-01

    and t,t-muconic acid were inversely associated with the alkaline comet assay. Conclusion: This cross-sectional study found associations between current environmental exposure to (potential) human carcinogens in 14–15-year-old Flemish adolescents and short-term (oxidative) damage to DNA. Prospective follow-up will be required to investigate whether long-term effects may occur due to complex environmental exposures. - Highlights: • Exposure to (potential) carcinogens is associated with (oxidative) damage to DNA. • Most associations of exposures are with urinary 8-OHdG. • 1-Hydroxypyrene and chromium are associated with the comet assay and 8-OHdG. • PFOA is associated with higher levels of DNA damage in the alkaline comet assay.

  14. Environmental exposure to human carcinogens in teenagers and the association with DNA damage

    Energy Technology Data Exchange (ETDEWEB)

    Franken, Carmen, E-mail: carmen.franken@vito.be [Flemish Institute for Technological Research (VITO), Mol (Belgium); Department of Biomedical Sciences, University of Antwerp, Antwerp (Belgium); Koppen, Gudrun; Lambrechts, Nathalie; Govarts, Eva [Flemish Institute for Technological Research (VITO), Mol (Belgium); Bruckers, Liesbeth [Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, Hasselt (Belgium); Den Hond, Elly [Flemish Institute for Technological Research (VITO), Mol (Belgium); Loots, Ilse [Political and Social Sciences, University of Antwerp, Antwerp (Belgium); Nelen, Vera [Provincial Institute for Hygiene, Antwerp (Belgium); Sioen, Isabelle [Department of Public Health, Ghent University, Ghent (Belgium); Department of Food Safety and Food Quality, Ghent University, Ghent (Belgium); Nawrot, Tim S. [Centre for Environmental Sciences, Hasselt University, Diepenbeek (Belgium); Department of Public Health & Primary Care, Leuven University, Leuven (Belgium); Baeyens, Willy [Department of Analytical and Environmental Chemistry, Vrije Universiteit Brussel, Brussels (Belgium); Van Larebeke, Nicolas [Department of Analytical and Environmental Chemistry, Vrije Universiteit Brussel, Brussels (Belgium); Department of Radiotherapy and Experimental Cancerology, Ghent University, Ghent (Belgium); Boonen, Francis; Ooms, Daniëlla; Wevers, Mai; Jacobs, Griet [Flemish Institute for Technological Research (VITO), Mol (Belgium); Covaci, Adrian [Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Antwerp (Belgium); Schettgen, Thomas [Department of Occupational and Social Medicine, RWTH Aachen University, Aachen (Germany); Schoeters, Greet [Flemish Institute for Technological Research (VITO), Mol (Belgium); Department of Biomedical Sciences, University of Antwerp, Antwerp (Belgium); University of Southern Denmark, Institute of Public Health, Department of Environmental Medicine, Odense (Denmark)

    2017-01-15

    and t,t-muconic acid were inversely associated with the alkaline comet assay. Conclusion: This cross-sectional study found associations between current environmental exposure to (potential) human carcinogens in 14–15-year-old Flemish adolescents and short-term (oxidative) damage to DNA. Prospective follow-up will be required to investigate whether long-term effects may occur due to complex environmental exposures. - Highlights: • Exposure to (potential) carcinogens is associated with (oxidative) damage to DNA. • Most associations of exposures are with urinary 8-OHdG. • 1-Hydroxypyrene and chromium are associated with the comet assay and 8-OHdG. • PFOA is associated with higher levels of DNA damage in the alkaline comet assay.

  15. A changing climate: impacts on human exposures to O3 using an integrated modeling methodology

    Science.gov (United States)

    Predicting the impacts of changing climate on human exposure to air pollution requires future scenarios that account for changes in ambient pollutant concentrations, population sizes and distributions, and housing stocks. An integrated methodology to model changes in human exposu...

  16. A short review on human exposure to and tissue distribution of per- and polyfluoroalkyl substances (PFASs).

    Science.gov (United States)

    Jian, Jun-Meng; Chen, Da; Han, Fu-Juan; Guo, Ying; Zeng, Lixi; Lu, Xingwen; Wang, Fei

    2018-09-15

    PFASs are widely distributed in natural and living environment and can enter human bodies via different routes. Many studies have reported that PFASs may be associated with human diseases, such as urine acid and thyroid diseases. In this study, we reviewed PFAS levels in human bodies reported in past seven years, including blood, urine, milk, and tissues (hair and nails). Most studies focused on human blood. Blood type, spatiality, human age, and gender were found to have a strong relationship with PFAS levels in blood samples. The PFAS distribution in urine samples was reported to be associated with the chain length of PFASs and human gender. Urinary excretion was found to be an important pathway of PFAS elimination. PFAS levels in human milk might be affected by various factors, such as mothers' age, dietary habit, parity of mothers and the interval of interpregnancy. Data in hair and nails remain very limited, but these matrices offer a non-invasive approach to evaluate human exposure to PFASs. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Metabolic profiling detects early effects of environmental and lifestyle exposure to cadmium in a human population

    Directory of Open Access Journals (Sweden)

    Ellis James K

    2012-06-01

    Full Text Available Abstract Background The 'exposome' represents the accumulation of all environmental exposures across a lifetime. Top-down strategies are required to assess something this comprehensive, and could transform our understanding of how environmental factors affect human health. Metabolic profiling (metabonomics/metabolomics defines an individual's metabolic phenotype, which is influenced by genotype, diet, lifestyle, health and xenobiotic exposure, and could also reveal intermediate biomarkers for disease risk that reflect adaptive response to exposure. We investigated changes in metabolism in volunteers living near a point source of environmental pollution: a closed zinc smelter with associated elevated levels of environmental cadmium. Methods High-resolution 1H NMR spectroscopy (metabonomics was used to acquire urinary metabolic profiles from 178 human volunteers. The spectral data were subjected to multivariate and univariate analysis to identify metabolites that were correlated with lifestyle or biological factors. Urinary levels of 8-oxo-deoxyguanosine were also measured, using mass spectrometry, as a marker of systemic oxidative stress. Results Six urinary metabolites, either associated with mitochondrial metabolism (citrate, 3-hydroxyisovalerate, 4-deoxy-erythronic acid or one-carbon metabolism (dimethylglycine, creatinine, creatine, were associated with cadmium exposure. In particular, citrate levels retained a significant correlation to urinary cadmium and smoking status after controlling for age and sex. Oxidative stress (as determined by urinary 8-oxo-deoxyguanosine levels was elevated in individuals with high cadmium exposure, supporting the hypothesis that heavy metal accumulation was causing mitochondrial dysfunction. Conclusions This study shows evidence that an NMR-based metabolic profiling study in an uncontrolled human population is capable of identifying intermediate biomarkers of response to toxicants at true environmental

  18. Multi-pathway human exposure assessment of phthalate esters and DINCH.

    Science.gov (United States)

    Giovanoulis, Georgios; Bui, Thuy; Xu, Fuchao; Papadopoulou, Eleni; Padilla-Sanchez, Juan A; Covaci, Adrian; Haug, Line S; Cousins, Anna Palm; Magnér, Jörgen; Cousins, Ian T; de Wit, Cynthia A

    2018-03-01

    Phthalate esters are substances mainly used as plasticizers in various applications. Some have been restricted and phased out due to their adverse health effects and ubiquitous presence, leading to the introduction of alternative plasticizers, such as DINCH. Using a comprehensive dataset from a Norwegian study population, human exposure to DMP, DEP, DnBP, DiBP, BBzP, DEHP, DINP, DIDP, DPHP and DINCH was assessed by measuring their presence in external exposure media, allowing an estimation of the total intake, as well as the relative importance of different uptake pathways. Intake via different uptake routes, in particular inhalation, dermal absorption, and oral uptake was estimated and total intake based on all uptake pathways was compared to the calculated intake from biomonitoring data. Hand wipe results were used to determine dermal uptake and compared to other exposure sources such as air, dust and personal care products. Results showed that the calculated total intakes were similar, but slightly higher than those based on biomonitoring methods by 1.1 to 3 times (median), indicating a good understanding of important uptake pathways. The relative importance of different uptake pathways was comparable to other studies, where inhalation was important for lower molecular weight phthalates, and negligible for the higher molecular weight phthalates and DINCH. Dietary intake was the predominant exposure route for all analyzed substances. Dermal uptake based on hand wipes was much lower (median up to 2000 times) than the total dermal uptake via air, dust and personal care products. Still, dermal uptake is not a well-studied exposure pathway and several research gaps (e.g. absorption fractions) remain. Based on calculated intakes, the exposure for the Norwegian participants to the phthalates and DINCH was lower than health based limit values. Nevertheless, exposure to alternative plasticizers, such as DPHP and DINCH, is expected to increase in the future and continuous

  19. Radiation exposure of fertile women in medical research studies

    International Nuclear Information System (INIS)

    Vetter, R.J.

    1988-01-01

    Fertile women may be exposed to ionizing radiation as human subjects in medical research studies. If the woman is pregnant, such exposures may result in risk to an embryo/fetus. Fertile women may be screened for pregnancy before exposure to ionizing radiation by interview, general examination, or pregnancy test. Use of the sensitive serum pregnancy test has become common because it offers concrete evidence that the woman is not pregnant (more specifically, that an embryo is not implanted). Evidence suggests that risk to the embryo from radiation exposure before organogenesis is extremely low or nonexistent. Further, demonstrated effects on organogenesis are rare or inconclusive at fetal doses below 50 mSv (5 rem). Therefore, there may be some level of radiation exposure below which risk to the fetus may be considered essentially zero, and a serum pregnancy test is unnecessary. This paper reviews the fetal risks and suggests that consideration be given to establishing a limit to the fetus of 0.5 mSv (50 mrem), below which pregnancy screening need not include the use of a serum pregnancy test

  20. Dose-rate models for human survival after exposure to ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Jones, T.D.; Morris, M.D.; Young, R.W.

    1986-01-01

    This paper reviews new estimates of the L/sub 50/ in man by Mole and by Rotblat, the biological processes contributing to hematologic death, the collection of animal experiments dealing with hematologic death, and the use of regression analysis to make new estimates of human mortality based on all relevant animal studies. Regression analysis of animal mortality data has shown that mortality is dependent strongly on dose rate, species, body weight, and time interval over which the exposure is delivered. The model has predicted human LD/sub 50/s of 194, 250, 310, and 360 rad to marrow when the exposure time is a minute, an hour, a day, and a week, respectively.

  1. Human brain wave activity during exposure to radiofrequency field emissions from mobile phones

    International Nuclear Information System (INIS)

    D'Costa, H.; Cosic, I.

    2003-01-01

    The aim of this study was to determine whether there is an effect of mobile phone electromagnetic field emissions on the human electroencephalograph (EEG). EEG recordings from ten awake subjects were taken during exposure to radiofrequency (RF) emissions from a mobile phone positioned behind the head. Two experimental trials were conducted. In the first trial, RF exposures were generated by a GSM mobile phone with the speaker disabled and configured to transmit at full-radiated power. During the second trial, exposures were generated by a non-modified GSM mobile phone in active standby mode. For each trial, subjects were exposed in five minute intervals to a randomized, interrupted sequence of five active and five sham exposures. The experiment was conducted under single-blind conditions. The average EEG band power in active exposure recordings was compared to corresponding sham recordings. Statistical tests indicated significant difference in the full-power mode trial within the EEG alpha (8-13 Hz) and beta (13-32 Hz) bands. A subsequent statistical analysis of median spectral power in discrete EEG rhythms revealed significant differences in 7 of the 32 distinct frequencies overall. In conclusion, the results of this study lend support to EEG effects from mobile phones activated in talk-mode. Copyright (2003) Australasian College of Physical Scientists and Engineers in Medicine

  2. Leptospira Exposure and Gardeners: A Case-Control Seroprevalence Study

    Science.gov (United States)

    Alvarado-Esquivel, Cosme; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Guido-Arreola, Carlos Alberto

    2016-01-01

    Background Leptospira can be found in soil. However, it is unclear whether occupational exposure to soil may represent a risk for Leptospira infection in humans. Therefore, we sought to determine the association of Leptospira IgG seroprevalence with the occupation of gardener, and to determine the epidemiological characteristics of gardeners associated with Leptospira exposure. Methods We performed a case-control study in 168 gardeners and 168 age- and gender-matched control subjects without gardening occupation in Durango City, Mexico. The seroprevalence of anti-Leptospira IgG antibodies in cases and controls was determined using an enzyme immunoassay. Bivariate and multivariate analyses were used to assess the association of Leptospira exposure and the characteristics of the gardeners. Results Anti-Leptospira IgG antibodies were found in 10 (6%) of 168 gardeners and in 15 (8.9%) of 168 control subjects (odds ratio (OR): 0.64; 95% confidence interval (CI): 0.28 - 1.48; P = 0.40). Multivariate analysis showed that Leptospira seropositivity was positively associated with female gender (OR: 5.82; 95% CI: 1.11 - 30.46; P = 0.03), and negatively associated with eating while working (OR: 0.21; 95% CI: 0.05 - 0.87; P = 0.03). In addition, multivariate analysis showed that high anti-Leptospira levels were associated with consumption of boar meat (OR: 28.00; 95% CI: 1.20 - 648.80; P = 0.03). Conclusions This is the first case-control study of Leptospira exposure in gardeners. Results do not support an association of Leptospira exposure with the occupation of gardener. However, further studies to confirm the lack of this association are needed. The potential role of consumption of boar meat in Leptospira infection deserves further investigation. PMID:26668679

  3. Hazard and risk assessment of human exposure to toxic metals using in vitro digestion assay

    Directory of Open Access Journals (Sweden)

    Hani A. Alhadrami

    2016-10-01

    Full Text Available Clean-up targets for toxic metals require that the site be “fit for purpose”. This means that targets are set with respect to defined receptors that reflect intended land-use. In this study, the likely threat of human exposure to toxic metals has been evaluated by simulating the human digestion process in vitro. The effects of key attributes (i.e. sample fraction size, pH, Kd and total metal concentrations on the bioavailability of Cu and Ni were also investigated. Total metal concentration was the key explanatory factor for Cu and Ni bioavailability. A comparative ranking of metal concentrations in the context of tolerable daily intakes for Cu and Ni confirmed that the pH has the greatest impact on metals bioavailability. Rapid screening of key attributes and total toxic metal doses can reveal the relative hazard imposed on human, and this approach should be considered when defining threshold values for human protection.

  4. Human health risks and socio-economic perspectives of arsenic exposure in Bangladesh: A scoping review.

    Science.gov (United States)

    Rahman, M Azizur; Rahman, A; Khan, M Zaved Kaiser; Renzaho, Andre M N

    2018-04-15

    Arsenic contamination of drinking water, which can occur naturally or because of human activities such as mining, is the single most important public health issue in Bangladesh. Fifty out of the 64 districts in the country have arsenic concentration of groundwater exceeding 50µgL -1 , the Bangladeshi threshold, affecting 35-77 million people or 21-48% of the total population. Chronic arsenic exposure through drinking water and other dietary sources is an important public health issue worldwide affecting hundreds of millions of people. Consequently, arsenic poisoning has attracted the attention of researchers and has been profiled extensively in the literature. Most of the literature has focused on characterising arsenic poisoning and factors associated with it. However, studies examining the socio-economic aspects of chronic exposure of arsenic through either drinking water or foods remain underexplored. The objectives of this paper are (i) to review arsenic exposure pathways to humans; (ii) to summarise public health impacts of chronic arsenic exposure; and (iii) to examine socio-economic implications and consequences of arsenicosis with a focus on Bangladesh. This scoping review evaluates the contributions of different exposure pathways by analysing arsenic concentrations in dietary and non-dietary sources. The socio-economic consequences of arsenicosis disease in Bangladesh are discussed in this review by considering food habits, nutritional status, socio-economic conditions, and socio-cultural behaviours of the people of the country. The pathways of arsenic exposure in Bangladesh include drinking water, various plant foods and non-dietary sources such as soil. Arsenic affected people are often abandoned by the society, lose their jobs and get divorced and are forced to live a sub-standard life. The fragile public health system in Bangladesh has been burdened by the management of thousands of arsenicosis victims in Bangladesh. Copyright © 2017 Elsevier Inc

  5. Relative source contributions for perchlorate exposures in a lactating human cohort

    Energy Technology Data Exchange (ETDEWEB)

    Kirk, Andrea B. [University of North Texas Health Sciences Center (United States); Dyke, Jason V. [University of Texas at Arlington (United States); Ohira, Shin-Ichi [Kumamoto University (Japan); Dasgupta, Purnendu K., E-mail: Dasgupta@uta.edu [University of Texas at Arlington (United States)

    2013-01-15

    Perchlorate is an iodine-uptake inhibitor and common contaminant of food and drinking water. Understanding the amount of perchlorate exposure occurring through non-water sources is essential for accurate estimates of human exposure levels, and establishment of drinking water limits for this pervasive contaminant. The study objective was to determine the amount of perchlorate intake derived from diet rather than water. Subjects provided drinking water samples, detailed fluid-intake records, 24 h urine collections and four milk samples for nine days. Samples were analyzed for perchlorate by isotope dilution ion chromatography–tandem mass spectrometry. Amounts of perchlorate derived from drinking water and dietary sources were calculated for each individual. Water of local origin was found to contribute a minor fraction of perchlorate intake. Estimated fraction intake from drinking water ranged from 0 to 36%. The mean and median dose of perchlorate derived from non-water sources by lactating women was 0.18 μg/kg/day (range: 0.06 to 0.36 μg/kg/day.) Lactating women consumed more fluid (mean 2.424 L/day) than has been assumed in recent risk assessments for perchlorate. The data reported here indicate that lactating women may be exposed to perchlorate through dietary sources at markedly higher levels than estimated previously. Exposures to perchlorate from non-water sources may be higher than recent estimates, including those used to develop drinking water standards. - Highlights: ► Residence in an area with perchlorate-contaminated water may be a poor predictor of exposure. ► Exposures to perchlorate from food are likely underestimated. ► The relative contributions for human perchlorate exposures should be weighted more heavily towards non-water sources.

  6. Detection of fluorotelomer alcohols in indoor environments and their relevance for human exposure.

    Science.gov (United States)

    Schlummer, Martin; Gruber, Ludwig; Fiedler, Dominik; Kizlauskas, Markus; Müller, Josef

    2013-07-01

    Fluorotelomer alcohols (FTOH) are important precursors of perfluorinated carboxylic acids (PFCA). These neutral and volatile compounds are frequently found in indoor air and may contribute to the overall human exposure to per- and polyfluorinated alkyl substances (PFAS). In this study air samples of ten workplace environments and a car interior were analysed. In addition, extracts and emissions from selected outdoor textiles were analysed in order to establish their potential contribution to the indoor levels of the above-mentioned compounds. Concentrations of FTOHs measured in air ranged from 0.15 to 46.8, 0.25 to 286, and 0.11 to 57.5ng/m(3) for 6:2, 8:2 and 10:2 FTOHs, respectively. The highest concentrations in air were identified in shops selling outdoor clothing, indicating outdoor textiles to be a relevant source of FTOH in indoor workplace environments. Total amounts of FTOH in materials of outdoor textiles accounted for selling outdoor textiles contains the highest levels of FTOH. Exposure of humans to perfluorooctanoic acid (PFOA) through absorption of FTOH and subsequent degradation is discussed on the basis of indoor air levels. Calculation of indoor air-related exposure using the median of the measured air levels revealed that exposure is on the same order of magnitude as the recently reported dietary intakes for a background-exposed population. On the basis of the 95th percentile, indoor air exposure to PFOA was estimated to exceed dietary exposure. However, indoor air-related intakes of FTOH are far below the tolerable daily intake (TDI) of PFOA, indicating that there is no risk to health, even when assuming an unrealistic complete degradation of FTOH into PFOA. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. In vitro atrazine-exposure inhibits human natural killer cell lytic granule release

    International Nuclear Information System (INIS)

    Rowe, Alexander M.; Brundage, Kathleen M.; Barnett, John B.

    2007-01-01

    The herbicide atrazine is a known immunotoxicant and an inhibitor of human natural killer (NK) cell lytic function. The precise changes in NK cell lytic function following atrazine exposure have not been fully elucidated. The current study identifies the point at which atrazine exerts its affect on the stepwise process of human NK cell-mediated lyses of the K562 target cell line. Using intracellular staining of human peripheral blood lymphocytes, it was determined that a 24-h in vitro exposure to atrazine did not decrease the level of NK cell lytic proteins granzyme A, granzyme B or perforin. Thus, it was hypothesized that atrazine exposure was inhibiting the ability of the NK cells to bind to the target cell and subsequently inhibit the release of lytic protein from the NK cell. To test this hypothesis, flow cytometry and fluorescent microscopy were employed to analyze NK cell-target cell co-cultures following atrazine exposure. These assays demonstrated no significant decrease in the level of target cell binding. However, the levels of NK intracellular lytic protein retained and the amount of lytic protein released were assessed following a 4-h incubation with K562 target cells. The relative level of intracellular lytic protein was 25-50% higher, and the amount of lytic protein released was 55-65% less in atrazine-treated cells than vehicle-treated cells following incubation with the target cells. These results indicate that ATR exposure inhibits the ability of NK cells to lyse target cells by blocking lytic granule release without affecting the ability of the NK cell to form stable conjugates with target cells

  8. HExpoChem: a systems biology resource to explore human exposure to chemicals

    DEFF Research Database (Denmark)

    Taboureau, Olivier; Jacobsen, Ulrik Plesner; Kalhauge, Christian Gram

    2013-01-01

    of computational biology approaches are needed to assess the health risks of chemical exposure. Here we present HExpoChem, a tool based on environmental chemicals and their bioactivities on human proteins with the objective of aiding the qualitative exploration of human exposure to chemicals. The chemical...

  9. Development of a physiologically based pharmacokinetic model for assessment of human exposure to bisphenol A

    International Nuclear Information System (INIS)

    Yang, Xiaoxia; Doerge, Daniel R.; Teeguarden, Justin G.; Fisher, Jeffrey W.

    2015-01-01

    A previously developed physiologically based pharmacokinetic (PBPK) model for bisphenol A (BPA) in adult rhesus monkeys was modified to characterize the pharmacokinetics of BPA and its phase II conjugates in adult humans following oral ingestion. Coupled with in vitro studies on BPA metabolism in the liver and the small intestine, the PBPK model was parameterized using oral pharmacokinetic data with deuterated-BPA (d 6 -BPA) delivered in cookies to adult humans after overnight fasting. The availability of the serum concentration time course of unconjugated d 6 -BPA offered direct empirical evidence for the calibration of BPA model parameters. The recalibrated PBPK adult human model for BPA was then evaluated against published human pharmacokinetic studies with BPA. A hypothesis of decreased oral uptake was needed to account for the reduced peak levels observed in adult humans, where d 6 -BPA was delivered in soup and food was provided prior to BPA ingestion, suggesting the potential impact of dosing vehicles and/or fasting on BPA disposition. With the incorporation of Monte Carlo analysis, the recalibrated adult human model was used to address the inter-individual variability in the internal dose metrics of BPA for the U.S. general population. Model-predicted peak BPA serum levels were in the range of pM, with 95% of human variability falling within an order of magnitude. This recalibrated PBPK model for BPA in adult humans provides a scientific basis for assessing human exposure to BPA that can serve to minimize uncertainties incurred during extrapolations across doses and species. - Highlights: • A PBPK model predicts the kinetics of bisphenol A (BPA) in adult humans. • Serum concentrations of aglycone BPA are available for model calibration. • Model predicted peak BPA serum levels for adult humans were in the range of pM. • Model predicted 95% of human variability fell within an order of magnitude.

  10. Development of a physiologically based pharmacokinetic model for assessment of human exposure to bisphenol A

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiaoxia, E-mail: xiaoxia.yang@fda.hhs.gov [Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Doerge, Daniel R. [Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States); Teeguarden, Justin G. [Health Effects and Exposure Science, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States); Fisher, Jeffrey W. [Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079 (United States)

    2015-12-15

    A previously developed physiologically based pharmacokinetic (PBPK) model for bisphenol A (BPA) in adult rhesus monkeys was modified to characterize the pharmacokinetics of BPA and its phase II conjugates in adult humans following oral ingestion. Coupled with in vitro studies on BPA metabolism in the liver and the small intestine, the PBPK model was parameterized using oral pharmacokinetic data with deuterated-BPA (d{sub 6}-BPA) delivered in cookies to adult humans after overnight fasting. The availability of the serum concentration time course of unconjugated d{sub 6}-BPA offered direct empirical evidence for the calibration of BPA model parameters. The recalibrated PBPK adult human model for BPA was then evaluated against published human pharmacokinetic studies with BPA. A hypothesis of decreased oral uptake was needed to account for the reduced peak levels observed in adult humans, where d{sub 6}-BPA was delivered in soup and food was provided prior to BPA ingestion, suggesting the potential impact of dosing vehicles and/or fasting on BPA disposition. With the incorporation of Monte Carlo analysis, the recalibrated adult human model was used to address the inter-individual variability in the internal dose metrics of BPA for the U.S. general population. Model-predicted peak BPA serum levels were in the range of pM, with 95% of human variability falling within an order of magnitude. This recalibrated PBPK model for BPA in adult humans provides a scientific basis for assessing human exposure to BPA that can serve to minimize uncertainties incurred during extrapolations across doses and species. - Highlights: • A PBPK model predicts the kinetics of bisphenol A (BPA) in adult humans. • Serum concentrations of aglycone BPA are available for model calibration. • Model predicted peak BPA serum levels for adult humans were in the range of pM. • Model predicted 95% of human variability fell within an order of magnitude.

  11. Mutagenic potential assessment associated with human exposure to natural radioactivity.

    Science.gov (United States)

    Marcon, Alexandre Endres; Navoni, Julio Alejandro; de Oliveira Galvão, Marcos Felipe; Garcia, Anuska Conde Fagundes Soares; do Amaral, Viviane Souza; Petta, Reinaldo Antônio; Campos, Thomas Ferreira da Costa; Panosso, Renata; Quinelato, Antônio Luiz; de Medeiros, Sílvia Regina Batistuzzo

    2017-01-01

    Lucrécia city, known to harbor a high cancer rate, is located in a semiarid region characterized by the presence of mineral reservoirs, facing a high exposure to metal and natural radioactivity. The present study aimed to assess the environmental scenario at a semiarid region located in Northeastern Brazil. Metal concentration, alpha and beta radiation, and cyanobacteria content in tap water along with indoor radon and gamma emitters (U, K and Th) concentrations were measured. In addition, mutagenic and nuclear instability effects were assessed using buccal micronucleus cytome assay. The study included five samplings corresponding to a period between 2007 and 2009. Drinking water from Lucrécia city presented levels of Mn, Ni and Cr along with cyanobacteria in concentrations one to four times higher than regulatory guidelines considered. Furthermore, high levels of all the tested radionuclides were found. A high percentage of the houses included in this study presented indoor radon concentrations over 100 Bq m -3 . The mean annual effective dose from Lucrécia houses was six times higher than observed in a control region. The levels of exposure in most of the Lucrécia houses were classified as middle to high. A significant mutagenic effect, represented as an increase of micronuclei (MN) frequency and nuclear abnormalities as nuclear buds (NB), binucleated cells (BN), and pyknotic cells (PYC) were found. The results obtained highlight the role of high background radioactivity on the observed mutagenic effect and could help to explain the exacerbated cancer rate reported in this locality. Copyright © 2016. Published by Elsevier Ltd.

  12. Urinary bisphenol A concentrations and their implications for human exposure in several Asian countries.

    Science.gov (United States)

    Zhang, Zifeng; Alomirah, Husam; Cho, Hyeon-Seo; Li, Yi-Fan; Liao, Chunyang; Minh, Tu Binh; Mohd, Mustafa Ali; Nakata, Haruhiko; Ren, Nanqi; Kannan, Kurunthachalam

    2011-08-15

    Bisphenol A (BPA) is an industrial chemical used in the manufacture of polycarbonate plastics and epoxy resins. Due to the potential of this compound to disrupt normal endocrinal functions, concerns over human exposure to BPA have been raised. Although several studies have reported human exposure to BPA in Western nations, little is known about exposure in Asian countries. In this study, we determined total urinary BPA concentrations (free plus conjugated) in 296 urine samples (male/female: 153/143) collected from the general population in seven Asian countries, China, India, Japan, Korea, Kuwait, Malaysia, and Vietnam, using high-performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS). On the basis of urinary BPA concentrations, we estimated the total daily intake. The results indicated that BPA was detected in 94.3% of the samples analyzed, at concentrations ranging from Malaysia (1.06 ng/mL, 2.31 μg/g), and Japan (0.95 ng/mL, 0.58 μg/g). Among the five age groups studied (≤ 19, 20-29, 30-39, 40-49, and ≥ 50 years), the highest median concentration of BPA was found in urine samples from the age group of ≤ 19 years. There was no significant difference in BPA concentrations between genders (male and female) or domicile of residence (rural and urban). The estimated median daily intakes of BPA for the populations in Kuwait, Korea, India, China, Vietnam, Malaysia, and Japan were 5.19, 3.69, 2.90, 2.13, 2.01, 1.80, and 1.61 μg/day, respectively. The estimated daily intake of BPA in the seven Asian countries was significantly lower than the tolerable daily intake recommended by the U.S. Environmental Protection Agency. This is the first study to document the occurrence of and human exposure to BPA in several Asian countries.

  13. Particle size fractionation and human exposure of polybrominated diphenyl ethers in indoor dust from Chicago.

    Science.gov (United States)

    Wei, Hua; Turyk, Mary; Cali, Salvatore; Dorevitch, Samuel; Erdal, Serap; Li, An

    2009-11-01

    The objective of this study was to investigate the concentration level, the mass distribution based on dust particle size, and the associated human exposure of polybrominated diphenyl ethers (PBDEs) in indoor dust. The total concentration of 13 PBDEs Sigma(13)(BDEs) was found to be 500-6,944 ng/g in indoor dusts, 4,000 ng/g in car interior dust, 260-300 ng/g in outdoor ambient air particles, 30 ng/g in carpet fibers, and as high as 0.5% in carpet padding. Selected dust samples were fractionated based on particle size, and over 80% of the Sigma(13)BDEs were associated with particles exposure of Americans to PBDEs via hand-to-mouth transfer of house dust was estimated under the central tendency exposure and reasonable maximum exposure scenarios. The results suggest that ingestion of PBDE-laden house dust via hand-to-mouth contact is likely a significant exposure pathway, especially for children.

  14. Human Rights Engagement and Exposure: New Scales to Challenge Social Work Education

    Science.gov (United States)

    McPherson, Jane; Abell, Neil

    2012-01-01

    Objectives: Advancing human rights is a core competency of U.S. social work education; yet, human rights attitudes and behaviors have never been measured in the social work literature. Thus, this article describes the development and initial validation of two scales, Human Rights Engagement in Social Work (HRESW) and Human Rights Exposure in…

  15. Human mercury exposure associated with small-scale gold mining in Burkina Faso.

    Science.gov (United States)

    Tomicic, Catherine; Vernez, David; Belem, Tounaba; Berode, Michèle

    2011-06-01

    In Burkina Faso, gold ore is one of the main sources of income for an important part of the active population. Artisan gold miners use mercury in the extraction, a toxic metal whose human health risks are well known. The aim of the present study was to assess mercury exposure as well as to understand the exposure determinants of gold miners in Burkinabe small-scale mines. The examined gold miners' population on the different selected gold mining sites was composed by persons who were directly and indirectly related to gold mining activities. But measurement of urinary mercury was performed on workers most susceptible to be exposed to mercury. Thus, occupational exposure to mercury was evaluated among ninety-three workers belonging to eight different gold mining sites spread in six regions of Burkina Faso. Among others, work-related exposure determinants were taken into account for each person during urine sampling as for example amalgamating or heating mercury. All participants were medically examined by a local medical team in order to identify possible symptoms related to the toxic effect of mercury. Mercury levels were high, showing that 69% of the measurements exceeded the ACGIH (American Conference of Industrial Hygienists) biological exposure indice (BEI) of 35 μg per g of creatinine (μg/g-Cr) (prior to shift) while 16% even exceeded 350 μg/g-Cr. Basically, unspecific but also specific symptoms related to mercury toxicity could be underlined among the persons who were directly related to gold mining activities. Only one-third among the studied subpopulation reported about less than three symptoms possibly associated to mercury exposure and nearly half of them suffered from at least five of these symptoms. Ore washers were more involved in the direct handling of mercury while gold dealers in the final gold recovery activities. These differences may explain the overexposure observed in gold dealers and indicate that the refining process is the major source

  16. Relationship between vapor intrusion and human exposure to trichloroethylene.

    Science.gov (United States)

    Archer, Natalie P; Bradford, Carrie M; Villanacci, John F; Crain, Neil E; Corsi, Richard L; Chambers, David M; Burk, Tonia; Blount, Benjamin C

    2015-01-01

    Trichloroethylene (TCE) in groundwater has the potential to volatilize through soil into indoor air where it can be inhaled. The purpose of this study was to determine whether individuals living above TCE-contaminated groundwater are exposed to TCE through vapor intrusion. We examined associations between TCE concentrations in various environmental media and TCE concentrations in residents. For this assessment, indoor air, outdoor air, soil gas, and tap water samples were collected in and around 36 randomly selected homes; blood samples were collected from 63 residents of these homes. Additionally, a completed exposure survey was collected from each participant. Environmental and blood samples were analyzed for TCE. Mixed model multiple linear regression analyses were performed to determine associations between TCE in residents' blood and TCE in indoor air, outdoor air, and soil gas. Blood TCE concentrations were above the limit of quantitation (LOQ; ≥ 0.012 µg L(-1)) in 17.5% of the blood samples. Of the 36 homes, 54.3%, 47.2%, and >84% had detectable concentrations of TCE in indoor air, outdoor air, and soil gas, respectively. Both indoor air and soil gas concentrations were statistically significantly positively associated with participants' blood concentrations (P = 0.0002 and P = 0.04, respectively). Geometric mean blood concentrations of residents from homes with indoor air concentrations of >1.6 µg m(-3) were approximately 50 times higher than geometric mean blood TCE concentrations in participants from homes with no detectable TCE in indoor air (P < .0001; 95% CI 10.4-236.4). This study confirms the occurrence of vapor intrusion and demonstrates the magnitude of exposure from vapor intrusion of TCE in a residential setting.

  17. Human exposure to PCDDs, PCDFs, and dioxin like PCBs in Japan, 2001

    Energy Technology Data Exchange (ETDEWEB)

    Mato, Y.; Nakayama, S. [Japan Environmental Sanitation Center, Kawasaki (Japan); Suzuki, N.; Morita, M. [National Inst. for Environmental Studies, Tsukuba (Japan); Kadokami, K. [Kitakyushu City Inst. of Environmental Sciences, Kitakyushu (Japan); Katatani, N. [Univ. of Yamanashi, Kofu (Japan); Nakano, T. [Hyogo Prefectural Inst. of Public Health and Environmental Sciences, Kobe (Japan); Matsuoka, T.; Takei, T. [Ministry of the Environment, Tokyo (Japan); Uchiyama, I. [Kyoto Univ. (Japan); Miyata, H. [Setsunan Univ., Hirakata (Japan); Toyoda, M. [Jissen Women' s Univ., Tokyo (Japan)

    2004-09-15

    In our previous study, we have estimated the level of human exposure to dioxins (PCDDs, PCDFs, and Dioxin like PCBs) in Japan based on dioxins monitoring data and results of total diet studies (TDS) in fiscal 2000 (April 2000- March 2001). It has been reported that the national PCDDs/DFs emission in 2001 against the 1997 level has been reduced by approximately 77% In addition, reduction of environmental levels was reported. The enforcement of Japan's Law Concerning Special Measures against Dioxins has significant impact on the reduction of the average dioxins concentrations in the ambient air. Therefore, the transitions of Japanese dioxins exposure levels in recent years are worthy of attention. In order to determine exposure level in fiscal 2001, collection and compilation for surveillance results derived from the regular environmental monitoring under the law as well as other dioxins surveys by national and local governmental bodies were continued, and the data were analyzed. The exposure level in fiscal 2001 was estimated by a ''point'' estimate (i.e., a single value derived from arithmetic means) approach based on the collected data. Because dioxins exposure is not clearly below the level of concern, an emphasis is placed on the importance of quantitatively characterizing the variability in exposure assessments. Therefore, the ''probabilistic'' approach using a Monte Carlo simulation was also conducted. However, elaboration in curve fitting to the distribution of dioxins intake through diet wasn't completely achieved due to the limitation of TDS data size in fiscal 2000 (n=16) in our previous study. In the present study, the curve fitting to diet were updated and elaborated, based on larger size of TDS data (n=54) by combining all the data in fiscal 1998-2001.

  18. Forecasting human exposure to atmospheric pollutants in Portugal - A modelling approach

    Science.gov (United States)

    Borrego, C.; Sá, E.; Monteiro, A.; Ferreira, J.; Miranda, A. I.

    2009-12-01

    Air pollution has become one main environmental concern because of its known impact on human health. Aiming to inform the population about the air they are breathing, several air quality modelling systems have been developed and tested allowing the assessment and forecast of air pollution ambient levels in many countries. However, every day, an individual is exposed to different concentrations of atmospheric pollutants as he/she moves from and to different outdoor and indoor places (the so-called microenvironments). Therefore, a more efficient way to prevent the population from the health risks caused by air pollution should be based on exposure rather than air concentrations estimations. The objective of the present study is to develop a methodology to forecast the human exposure of the Portuguese population based on the air quality forecasting system available and validated for Portugal since 2005. Besides that, a long-term evaluation of human exposure estimates aims to be obtained using one-year of this forecasting system application. Additionally, a hypothetical 50% emission reduction scenario has been designed and studied as a contribution to study emission reduction strategies impact on human exposure. To estimate the population exposure the forecasting results of the air quality modelling system MM5-CHIMERE have been combined with the population spatial distribution over Portugal and their time-activity patterns, i.e. the fraction of the day time spent in specific indoor and outdoor places. The population characterization concerning age, work, type of occupation and related time spent was obtained from national census and available enquiries performed by the National Institute of Statistics. A daily exposure estimation module has been developed gathering all these data and considering empirical indoor/outdoor relations from literature to calculate the indoor concentrations in each one of the microenvironments considered, namely home, office/school, and other

  19. Numerical evaluation of human exposure to WiMax patch antenna in tablet or laptop.

    Science.gov (United States)

    Siervo, Beatrice; Morelli, Maria Sole; Landini, Luigi; Hartwig, Valentina

    2018-04-30

    The use of wireless communication devices, such as tablets or laptops, is increasing among children. Only a few studies assess specific energy absorption rate (SAR) due to exposure from wireless-enabled tablets and laptops, in particular with Worldwide Interoperability for Microwave Access (WiMax) technology. This paper reports the estimation of the interaction between an E-shaped patch antenna (3.5 GHz) and human models, by means of finite-difference time-domain (FDTD) method. Specifically, four different human models (young adult male, young adult female, pre-teenager female, male child) in different exposure conditions (antenna at different distances from the human model, in different positions, and orientations) were considered and whole-body, 10 and 1 g local SAR and magnetic field value (Bmax) were evaluated. From our results, in some worst-case scenarios involving male and female children's exposure, the maximum radiofrequency energy absorption (hot spots) is located in more sensitive organs such as eye, genitals, and breast. Bioelectromagnetics. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  20. Developing and evaluating distributions for probabilistic human exposure assessments

    Energy Technology Data Exchange (ETDEWEB)

    Maddalena, Randy L.; McKone, Thomas E.

    2002-08-01

    reviewing it. For deterministic risk assessments, the use of default inputs has improved the ease and the consistency of both performing and reviewing assessments. By analogy, it is expected that similar advantage will be seen in the field of probabilistic risk assessment through the introduction of default distributions. In Part 2 of this report, we consider when a default distribution might be appropriate for use in PRA and work towards development of recommended task-specific distributions for several frequently used exposure factors. An approach that we develop using body weight and exposure duration as case studies offers a transparent way for developing task-specific exposure factor distributions. A third case study using water intake highlights the need for further study aimed at improving the relevance of ''short-term'' data before recommendations on task-specific distributions of water intake can be made.

  1. [Indoor dust as a pathway of human exposure to polybrominated diphenyl ethers (PBDEs)].

    Science.gov (United States)

    Góralczyk, Katarzyna; Struciński, Paweł; Hernik, Agnieszka; Czaja, Katarzyna; Korcz, Wojciech; Minorczyk, Maria; Ludwicki, Jan K

    2012-01-01

    The brominated diphenyl ethers (PBDEs) belong to a class of synthetic, additive brominated flame retardants (BFRs). PBDEs are used to reduce the flammability of commercial and household products such as textiles, various plastic polymers, furnishing foam, and electronic equipment. People spend a large percentage of their life-time indoors at home, in offices and cars, etc, providing many opportunities for lengthy exposure to PBDEs from residential settings and commercial products in an indoor environment. In recent time, the foodstuffs, mainly food of animal origin, have been indicated as the main pathway of human exposure to PBDEs. However, many studies have shown that the indoor environment, mainly indoor dust, can be also a significant source of exposure to PBDEs, especially for younger children (toddlers) because of their behavioral patterns, eg. putting fingers, toys, and other items in their mouth. Numerous studies show that the median intakes of PBDEs via dust for adult range from 1.41 to 277 ng x day(-1) is lower than that via food which range from 135 to 333 ng x day-', while the median intake of these compounds via indoor dust for children range from 101 to 404 ng x day(-1) is much higher than via food: 77-190 ng x day(-1). The congener pattern observed in the indoor dust is different to that found in food. The indoor dust is dominated by the congener BDE-209 vs. food where the most dominated congeners are BDE-47 and BDE-99. Human exposure to PBDEs and other brominated flame retardants (BFRs) is widely widespread throughout the world and it depends on a country range of usage, production and legislation concerning these chemicals as well as a citizen's behavior. Generally, human exposure has been found higher in North America than in Europe and Asia. Within European countries the significant highest concentrations in dust have been found in the United Kingdom. It should be noted that many uncertainty factors such as personal habits, dietary preferences

  2. Mixtures of endocrine disrupting contaminants modelled on human high end exposures

    DEFF Research Database (Denmark)

    Christiansen, Sofie; Kortenkamp, A.; Petersen, Marta Axelstad

    2012-01-01

    exceeding 1 is expected to lead to effects in the rat, a total dose more than 62 times higher than human exposures should lead to responses. Considering the high uncertainty of this estimate, experience on lowest‐observed‐adverse‐effect‐level (LOAEL)/NOAEL ratios and statistical power of rat studies, we...... expected that combined doses 150 times higher than high end human intake estimates should give no, or only borderline effects, whereas doses 450 times higher should produce significant responses. Experiments indeed showed clear developmental toxicity of the 450‐fold dose in terms of increased nipple...... though each individual chemical is present at low, ineffective doses, but the effects of mixtures modelled based on human intakes have not previously been investigated. To address this issue for the first time, we selected 13 chemicals for a developmental mixture toxicity study in rats where data about...

  3. Physiological responses to exposure to carbon dioxide and human bioeffluents

    DEFF Research Database (Denmark)

    Zhang, Xiaojing; Wargocki, Pawel; Lian, Zhiwei

    2015-01-01

    Present paper describes physiological responses as a result of exposures to CO2 (between 500 ppm to 3,000 ppm) with and without bioeffluents. Twenty-five subjects participated. They were exposed in the climate chamber for 255 minutes in groups of five at a time. During exposure, they performed di...

  4. Human Mercury Exposure in Yanomami Indigenous Villages from the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Claudia M. Vega

    2018-05-01

    Full Text Available In the Brazilian Amazon, where the majority of Yanomami villages are settled, mercury (Hg exposure due to artisanal small-scale gold mining (ASGM has been reported since the 1980s. This study assessed mercury exposure in the Yanomami reserve and whether the level of contamination was related to the ASGM geographical location. It was conducted using a cross-sectional study of 19 villages. Direct interviews were performed and hair samples were used as a bioindicator of Hg exposure. The Prevalence-Ratio (PR was estimated as an indicator of association between ASGM geographical locations and human exposure to mercury. Mercury levels (239 hair samples ranged between 0.4 and 22.1 μg·g−1 and presented substantial differences amongst the villages. In the Waikas-Aracaça region, where current ASGM was reported, we observed the highest Hg concentrations (median = 15.5 μg·g−1. Almost all participants presented with hair-Hg levels >6 μg·g−1 (prevalence = 92.3%. In the Paapiu region, we observed the lowest concentrations (median = 3.2 μg·g−1; prevalence = 6.7%. Our findings showed that the Waikas Ye’kuana and Waikas Aracaca villages presented with 4.4 (PR = 4.4; Confidence Interval (CI 95% = 2.2–9.0 and 14.0 (PR = 14.0; CI 95% = 7.9–24.9 times higher prevalence of hair-Hg concentration, respectively, compared with Paapiu. Considering seasonal variation of Hg-exposure, the lowest concentrations were observed during the wet season (June–September and the highest in the dry season (December–April. Our study suggests that there is an association between mercury exposure and ASGM geographical locations.

  5. Human Mercury Exposure in Yanomami Indigenous Villages from the Brazilian Amazon.

    Science.gov (United States)

    Vega, Claudia M; Orellana, Jesem D Y; Oliveira, Marcos W; Hacon, Sandra S; Basta, Paulo C

    2018-05-23

    In the Brazilian Amazon, where the majority of Yanomami villages are settled, mercury (Hg) exposure due to artisanal small-scale gold mining (ASGM) has been reported since the 1980s. This study assessed mercury exposure in the Yanomami reserve and whether the level of contamination was related to the ASGM geographical location. It was conducted using a cross-sectional study of 19 villages. Direct interviews were performed and hair samples were used as a bioindicator of Hg exposure. The Prevalence-Ratio (PR) was estimated as an indicator of association between ASGM geographical locations and human exposure to mercury. Mercury levels (239 hair samples) ranged between 0.4 and 22.1 μg·g -1 and presented substantial differences amongst the villages. In the Waikas-Aracaça region, where current ASGM was reported, we observed the highest Hg concentrations (median = 15.5 μg·g -1 ). Almost all participants presented with hair-Hg levels >6 μg·g -1 (prevalence = 92.3%). In the Paapiu region, we observed the lowest concentrations (median = 3.2 μg·g -1 ; prevalence = 6.7%). Our findings showed that the Waikas Ye'kuana and Waikas Aracaca villages presented with 4.4 (PR = 4.4; Confidence Interval (CI) 95% = 2.2⁻9.0) and 14.0 (PR = 14.0; CI 95% = 7.9⁻24.9) times higher prevalence of hair-Hg concentration, respectively, compared with Paapiu. Considering seasonal variation of Hg-exposure, the lowest concentrations were observed during the wet season (June⁻September) and the highest in the dry season (December⁻April). Our study suggests that there is an association between mercury exposure and ASGM geographical locations.

  6. Exposure to 60-Hz magnetic fields and proliferation of human astrocytoma cells in vitro.

    Science.gov (United States)

    Wei, M; Guizzetti, M; Yost, M; Costa, L G

    2000-02-01

    Epidemiological studies have suggested that exposure to electric and magnetic fields (EMF) may be associated with an increased incidence of brain tumors, most notably astrocytomas. However, potential cellular or molecular mechanisms involved in these effects of EMF are not known. In this study we investigated whether exposure to 60-Hz sinusoidal magnetic fields (0.3-1.2 G for 3-72 h) would cause proliferation of human astrocytoma cells. Sixty-Hertz magnetic fields (MF) caused a time- and dose-dependent increase in proliferation of astrocytoma cells, measured by (3)H-thymidine incorporation and by flow cytometry, and strongly potentiated the effect of two agonists (the muscarinic agonist carbachol and the phorbol ester PMA). However, MF had no effect on DNA synthesis of rat cortical astrocytes, i.e., of similar, nontransformed cells. To determine the amount of heating induced by MF, temperatures were also recorded in the medium. Both 1.2 G MF and a sham exposure caused a 0.7 degrees C temperature increase in the medium; however, (3)H-thymidine incorporation induced by sham exposure was significantly less than that caused by MF. GF 109203X, a rather specific protein kinase C (PKC) inhibitor, and down-regulation of PKC inhibited the effect of MF on basal and on agonist-stimulated (3)H-thymidine incorporation. These data indicate that MF can increase the proliferation of human astrocytoma cells and strongly potentiate the effects of two agonists. These findings may provide a biological basis for the observed epidemiological associations between MF exposure and brain tumors. Copyright 2000 Academic Press.

  7. [DNA damage in human pleural mesothelial cells induced by exposure to carbon nanotubes].

    Science.gov (United States)

    Ogasawara, Yuki; Umezu, Noriaki; Ishii, Kazuyuki

    2012-01-01

    Nanomaterials are currently used in electronics, industrial materials, cosmetics, and medicine because they have useful physicochemical properties, such as strength, conductivity, durability, and chemical stability. As these materials have become widespread, many questions have arisen regarding their effects on health and the environment. In particular, recent studies have demonstrated that carbon nanotubes (CNTs) cause significant inflammation and mesothelioma in vivo. In this study, we investigated the potential risk posed by singlewalled carbon nanotube (SWCNT) and multiwalled carbon nanotube (MWCNT) exposure in human pleural mesothelial cells. CNT cytotoxicity was determined by a trypan blue exclusion assay, and DNA damage was detected by an alkaline comet assay. The concentration of 8-oxodeoxyguanosine (8-OHdG) in DNA was measured by high perhormance liquid chromatography with electrochemical detection. The expression of base excision repair enzymes in the cell was estimated by immunoblot analysis. We observed inhibitory effects on cell proliferation and the induction of DNA damage following exposure of cells to purified CNTs that were suspended in dispersion medium. However, accumulation of 8-OHdG in DNA was not found. In addition, the expression levels of base excision enzymes that are involved in hOGG1, hMTH1, and MYH in MeT-5A cells remained unchanged for 24 h after carbon nanotube exposure. CNTs significantly inhibit cell proliferation and decrease DNA damage in human pleural mesothelial cells. Our results indicate that the mechanism of CNT-induced genotoxicity is different from that following exposure to reactive oxygen species, which causes oxidative DNA modifications and 8-OHdG production. Further investigation is required to characterize the specific DNA mutations that occur following CNT exposure.

  8. Risk Assessment and Implication of Human Exposure to Road Dust Heavy Metals in Jeddah, Saudi Arabia.

    Science.gov (United States)

    Shabbaj, Ibrahim I; Alghamdi, Mansour A; Shamy, Magdy; Hassan, Salwa K; Alsharif, Musaab M; Khoder, Mamdouh I

    2017-12-26

    Data dealing with the assessment of heavy metal pollution in road dusts in Jeddah, Saudi Arabia and its implication to human health risk of human exposure to heavy metals, are scarce. Road dusts were collected from five different functional areas (traffic areas (TA), parking areas (PA), residential areas (RA), mixed residential commercial areas (MCRA) and suburban areas (SA)) in Jeddah and one in a rural area (RUA) in Hada Al Sham. We aimed to measure the pollution levels of heavy metals and estimate their health risk of human exposure applying risk assessment models described by United States Environmental Protection Agency (USEPA). Using geo-accumulation index (I geo ), the pollution level of heavy metals in urban road dusts was in the following order Cd > As > Pb > Zn > Cu > Ni > Cr > V > Mn > Co > Fe. Urban road dust was found to be moderately to heavily contaminated with As, Pb and Zn, and heavily to extremely contaminated with Cd. Calculation of enrichment factor (EF) revealed that heavy metals in TA had the highest values compared to that of the other functional areas. Cd, As, Pb, Zn and Cu were severely enriched, while Mn, V, Co, Ni and Cr were moderately enriched. Fe was considered as a natural element and consequently excluded. The concentrations of heavy metals in road dusts of functional areas were in the following order: TA > PA > MCRA > SA > RA > RUA. The study revealed that both children and adults in all studied areas having health quotient (HQ) exposure route was ingestion. The cancer risk for children and adults from exposure to Pb, Cd, Co, Ni, and Cr was found to be negligible (≤1 × 10 -6 ).

  9. Secretion of interferon gamma from human immune cells is altered by exposure to tributyltin and dibutyltin.

    Science.gov (United States)

    Lawrence, Shanieek; Reid, Jacqueline; Whalen, Margaret

    2015-05-01

    Tributyltin (TBT) and dibutyltin (DBT) are widespread environmental contaminants found in food, beverages, and human blood samples. Both of these butyltins (BTs) interfere with the ability of human natural killer (NK) cells to lyse target cells and alter secretion of the pro-inflammatory cytokine tumor necrosis factor alpha (TNFα) from human immune cells in vitro. The capacity of BTs to interfere with secretion of other pro-inflammatory cytokines has not been examined. Interferon gamma (IFNγ) is a modulator of adaptive and innate immune responses, playing an important role in overall immune competence. This study shows that both TBT and DBT alter secretion of IFNγ from human immune cells. Peripheral blood cell preparations that were increasingly reconstituted were used to determine if exposures to either TBT or DBT affected IFNγ secretion and how the makeup of the cell preparation influenced that effect. IFNγ secretion was examined after 24 h, 48 h, and 6 day exposures to TBT (200 - 2.5 nM) and DBT (5 - 0.05 µM) in highly enriched human NK cells, a monocyte-depleted preparation of PBMCs, and monocyte-containing PBMCs. Both BTs altered IFNγ secretion from immune cells at most of the conditions tested (either increasing or decreasing secretion). However, there was significant variability among donors as to the concentrations and time points that showed changes as well as the baseline secretion of IFNγ. The majority of donors showed an increase in IFNγ secretion in response to at least one concentration of TBT or DBT at a minimum of one length of exposure. © 2013 Wiley Periodicals, Inc.

  10. Pulmonary Inflammatory Responses to Acute Meteorite Dust Exposures - Implications for Human Space Exploration

    Science.gov (United States)

    Harrington, A. D.; McCubbin, F. M.; Vander Kaaden, K. E.; Kaur, J.; Smirnov, A.; Galdanes, K.; Schoonen, M. A. A.; Chen, L. C.; Tsirka, S. E.; Gordon, T.

    2018-01-01

    New initiatives to send humans to Mars within the next few decades are illustrative of the resurgence of interest in space travel. However, as with all exploration, there are risks. The Human Research Roadmap developed by NASA identifies the Risk of Adverse Health and Performance Effects of Celestial Dust Exposure as an area of concern. Extended human exploration will further increase the probability of inadvertent and repeated exposures to celestial dusts.

  11. Does D-cycloserine enhance exposure therapy for anxiety disorders in humans? A meta-analysis.

    Directory of Open Access Journals (Sweden)

    Helga Rodrigues

    Full Text Available The treatment of anxiety is on the edge of a new era of combinations of pharmacologic and psychosocial interventions. A new wave of translational research has focused on the use of pharmacological agents as psychotherapy adjuvants using neurobiological insights into the mechanism of the action of certain psychological treatments such as exposure therapy. Recently, d-cycloserine (DCS an antibiotic used to treat tuberculosis has been applied to enhance exposure-based treatment for anxiety and has proved to be a promising, but as yet unproven intervention. The present study aimed to evaluate the efficacy of DCS in the enhancement of exposure therapy in anxiety disorders. A systematic review/meta-analysis was conducted. Electronic searches were conducted in the databases ISI-Web of Science, Pubmed and PsycINFO. We included only randomized, double-blind, placebo-controlled trials with humans, focusing on the role of DCS in enhancing the action of exposure therapy for anxiety disorders. We identified 328 references, 13 studies were included in our final sample: 4 on obsessive-compulsive disorder, 2 on panic disorder, 2 on social anxiety disorder, 2 on posttraumatic stress disorder, one on acrophobia, and 2 on snake phobia. The results of the present meta-analysis show that DCS enhances exposure therapy in the treatment of anxiety disorders (Cohen d =  -0.34; CI: -0.54 to -0.14, facilitating the specific process of extinction of fear. DCS seems to be effective when administered at a time close to the exposure therapy, at low doses and a limited number of times. DCS emerges as a potential new therapeutic approach for patients with refractory anxiety disorders that are unresponsive to the conventional treatments available. When administered correctly, DCS is a promising strategy for augmentation of CBT and could reduce health care costs, drop-out rates and bring faster relief to patients.

  12. Data sources and methods for ascertaining human exposure to drugs.

    Science.gov (United States)

    Jones, J K; Kennedy, D L

    Estimates of population exposure based on drug use data are critical elements in the post marketing surveillance of drugs and provide a context for assessing the various risks and benefits associated with drug treatment. Such information is important in predicting morbidity and planning public health protection strategies, indepth studies, and regulatory actions. Knowledge that a population of one thousand instead of one million may potentially be exposed to a drug can help determine how a particular regulatory problem will be handled and would obviously be a major determinant in designing a case-control or cohort study. National estimates of drug use give an overview of the most commonly used drug therapies in current practice. They also furnish valuable comparison data for specific studies of drug use limited to one group of drugs, one geographic region, or one medical care setting. The FDA has access to several different national drug use data bases, each measuring a different point in the drug distribution channels. None covers the entire spectrum of drug exposures. The major "holes" in this patchwork of data bases are the inability to measure OTC drug use with any accuracy and the lack of qualitative information on drug use in hospitals. In addition, there is no patient linkage with the data. The data can only show trends in drug use. They impart no sense of the longitudinal use of drugs for individual patients. There is no direct connection between the different data bases, all of which have their own sampling frames and their own projection methodologies. The market research companies have complete control over these methodologies and they are subject to periodic changes, a situation not entirely satisfactory for epidemiologic research. Sometimes it is a struggle to keep up with these changes. Over the past two years, every one of these data bases has undergone some type of sampling or projection methodology change. One important limitation to the use of all

  13. A flexible matrix-based human exposure assessment framework suitable for LCA and CAA

    DEFF Research Database (Denmark)

    Jolliet, Olivier; Ernstoff, Alexi; Huang, Lei

    2016-01-01

    are not applicable to all types of near-field chemical releases from consumer products, e.g. direct dermal application. A consistent near-and far-field framework is needed for life cycle assessment (LCA) and chemical alternative assessment (CAA) to inform mitigation of human exposure to harmful chemicals. To close......Humans can be exposed to chemicals via near-field exposure pathways (e.g. through consumer product use) and far-field exposure pathways (e.g. through environmental emissions along product life cycles). Pathways are often complex where chemicals can transfer directly from products to humans during...... use or exchange between near-and far-field compartments until sub -fractions reach humans via inhalation, ingestion or dermal uptake. Currently, however, multimedia exposure models mainly focus on far-field exposure pathways. Metrics and modeling approaches used in far-field, emission-based models...

  14. The U.S. National Health and Nutrition Examination Survey and human exposure to environmental chemicals.

    Science.gov (United States)

    Calafat, Antonia M

    2012-02-01

    Researchers are increasingly interested in using human biomonitoring - the measurement of chemicals, their metabolites or specific reaction products in biological specimens/body fluids - for investigating exposure to environmental chemicals. General population human biomonitoring programs are useful for investigating human exposure to environmental chemicals and an important tool for integrating environment and health. One of these programs, the National Health and Nutrition Examination Survey (NHANES), conducted in the United States is designed to collect data on the health and nutritional status of the noninstitutionalized, civilian U.S. population. NHANES includes a physical examination, collecting a detailed medical history, and collecting biological specimens (i.e., blood and urine). These biological specimens can be used to assess exposure to environmental chemicals. NHANES human biomonitoring data can be used to establish reference ranges for selected chemicals, provide exposure data for risk assessment, and monitor exposure trends. Published by Elsevier GmbH.

  15. Assessing human exposure risk to cadmium through inhalation and seafood consumption

    International Nuclear Information System (INIS)

    Ju, Yun-Ru; Chen, Wei-Yu; Liao, Chung-Min

    2012-01-01

    Highlights: ► Trophically available fraction in seafood and bioaccessibility is linked. ► Human health risk to Cd can via inhalation and seafood consumption. ► Female had the higher Cd accumulation in urine and blood than male. ► Cigarette smoking is a major determinant of human Cd intake. - Abstract: The role of cadmium (Cd) bioaccessibility in risk assessment is less well studied. The aim of this study was to assess human health risk to Cd through inhalation and seafood consumption by incorporating bioaccessibility. The relationships between trophically available Cd and bioaccessibility were constructed based on available experimental data. We estimated Cd concentrations in human urine and blood via daily intake from seafood consumption and inhalation based on a physiologically-based pharmacokinetic (PBPK) model. A Hill-based dose–response model was used to assess human renal dysfunction and peripheral arterial disease risks for long-term Cd exposure. Here we showed that fish had higher bioaccessibility (∼83.7%) than that of shellfish (∼73.2%) for human ingestion. Our results indicated that glomerular and tubular damage among different genders and smokers ranged from 18.03 to 18.18%. Our analysis showed that nonsmokers had 50% probability of peripheral arterial disease level exceeding from 3.28 to 8.80%. Smoking populations had 2–3 folds higher morbidity risk of peripheral arterial disease than those of nonsmokers. Our study concluded that the adverse effects of Cd exposure are exacerbated when high seafood consumption coincides with cigarette smoking. Our work provides a framework that could more accurately address risk dose dependency of Cd hazard.

  16. Abundant Rodent Furan-Derived Urinary Metabolites Are Associated with Tobacco Smoke Exposure in Humans.

    Science.gov (United States)

    Grill, Alex E; Schmitt, Thaddeus; Gates, Leah A; Lu, Ding; Bandyopadhyay, Dipankar; Yuan, Jian-Min; Murphy, Sharon E; Peterson, Lisa A

    2015-07-20

    Furan, a possible human carcinogen, is found in heat treated foods and tobacco smoke. Previous studies have shown that humans are capable of converting furan to its reactive metabolite, cis-2-butene-1,4-dial (BDA), and therefore may be susceptible to furan toxicity. Human risk assessment of furan exposure has been stymied because of the lack of mechanism-based exposure biomarkers. Therefore, a sensitive LC-MS/MS assay for six furan metabolites was applied to measure their levels in urine from furan-exposed rodents as well as in human urine from smokers and nonsmokers. The metabolites that result from direct reaction of BDA with lysine (BDA-N(α)-acetyllysine) and from cysteine-BDA-lysine cross-links (N-acetylcysteine-BDA-lysine, N-acetylcysteine-BDA-N(α)-acetyllysine, and their sulfoxides) were targeted in this study. Five of the six metabolites were identified in urine from rodents treated with furan by gavage. BDA-N(α)-acetyllysine, N-acetylcysteine-BDA-lysine, and its sulfoxide were detected in most human urine samples from three different groups. The levels of N-acetylcysteine-BDA-lysine sulfoxide were more than 10 times higher than that of the corresponding sulfide in many samples. The amount of this metabolite was higher in smokers relative to that in nonsmokers and was significantly reduced following smoking cessation. Our results indicate a strong relationship between BDA-derived metabolites and smoking. Future studies will determine if levels of these biomarkers are associated with adverse health effects in humans.

  17. Mitochondrial function in human skeletal muscle following high-altitude exposure

    DEFF Research Database (Denmark)

    Jacobs, Robert A; Boushel, Robert; Wright-Paradis, Cynthia

    2013-01-01

    Studies regarding mitochondrial modifications in human skeletal muscle following acclimatization to high altitude are conflicting, and these inconsistencies may be due to the prevalence of representing mitochondrial function through static and isolated measurements of specific mitochondrial...... characteristics. The aim of this study, therefore, was to investigate mitochondrial function in response to high-altitude acclimatization through measurements of respiratory control in the vastus lateralis muscle. Skeletal muscle biopsies were obtained from 10 lowland natives prior to and again after a total of 9......-11 days of exposure to 4559 m. High-resolution respirometry was performed on the muscle samples to compare respiratory chain function and respiratory capacities. Respirometric analysis revealed that mitochondrial function was largely unaffected, because high-altitude exposure did not affect the capacity...

  18. Understanding and characterisation of the risks to human health from exposure to low levels of radiation

    International Nuclear Information System (INIS)

    Goodhead, D. T.

    2009-01-01

    Exposure to ionising radiation can lead to a wide variety of health effects. Cancer is judged to be the main risk from radiation at low doses and low dose rates, and controlling this risk has been the main factor in developing radiation protection practice. Conventional paradigms of radiobiology and radiation carcinogenesis have served to guide extrapolations of epidemiological data on exposed human populations, so as to estimate risks at low doses and low dose rates, to other types of ionising radiation and to non-uniform exposures. These paradigms are founded on a century of experimental and theoretical studies, but nevertheless there remain many uncertainties. Major assumptions and simplifications have been introduced to achieve a practical system of additive doses (and implied risks) for radiation protection. Advancing epidemiological studies and experimental research continue to reduce uncertainties in some areas while, in others, they raise new challenges to the generality and applicability of the conventional paradigms. (authors)

  19. Bisphenol A in supermarket receipts and its exposure to human in Shenzhen, China.

    Science.gov (United States)

    Lu, Shao-You; Chang, Wen-Jing; Sojinu, Samuel O; Ni, Hong-Gang

    2013-08-01

    Paper receipt has been documented as one major source of bisphenol A (BPA) for human exposure but little has been done by researchers to elaborate the potential health risk caused by handling paper receipt up to date. In the present study, BPA was analyzed in 42 supermarket receipts collected from Shenzhen, China. BPA was detected in all samples at concentrations ranging from 2.58 to 14.7mgg(-1). In most cases, the total amount of BPA on the receipt was at least one thousand times the amount found in the epoxy lining of a food can, another controversial use of the chemical. The estimated daily intakes (EDI) of BPA via handling of supermarket receipt ranged from 2 to 347μgday(-1) (mean, 40.4μgday(-1)) for a supermarket cashier and from 0.24 to 3.98μgday(-1) (mean, 0.69μgday(-1)) for general population. Based on the cumulative probability distribution of the calculated daily exposure to BPA via handling supermarket receipt, the EDI at the 0.1th and 1th percentile for supermarket cashier and general population, were already larger than 100ng (kgbw)(-1)day(-1), while at the 0.2th and 71th percentile, the EDI for both populations reached 1000ng (kgbw)(-1)day(-1). Considering the adverse endocrine disruptive effects of BPA and the dosage exposure level (from tens to hundreds ng (kgbw)(-1)day(-1)), human exposure to BPA in Shenzhen deserves more attention. Sensitivity analysis result showed that the handling time and frequency of supermarket receipts are the most important variables that contributed to most of the total variance of exposure. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Critical evaluation of key evidence on the human health hazards of exposure to bisphenol A

    Science.gov (United States)

    Hengstler, JG; Foth, H; Gebel, T; Kramer, P-J; Lilienblum, W; Schweinfurth, H; Völkel, W; Wollin, K-M; Gundert-Remy, U

    2011-01-01

    Despite the fact that more than 5000 safety-related studies have been published on bisphenol A (BPA), there seems to be no resolution of the apparently deadlocked controversy as to whether exposure of the general population to BPA causes adverse effects due to its estrogenicity. Therefore, the Advisory Committee of the German Society of Toxicology reviewed the background and cutting-edge topics of this BPA controversy. The current tolerable daily intake value (TDI) of 0.05 mg/kg body weight [bw]/day, derived by the European Food Safety Authority (EFSA), is mainly based on body weight changes in two- and three-generation studies in mice and rats. Recently, these studies and the derivation of the TDI have been criticized. After having carefully considered all arguments, the Committee had to conclude that the criticism was scientifically not justified; moreover, recently published additional data further support the reliability of the two-and three-generation studies demonstrating a lack of estrogen-dependent effects at and below doses on which the current TDI is based. A frequently discussed topic is whether doses below 5 mg/ kg bw/day may cause adverse health effects in laboratory animals. Meanwhile, it has become clear that positive results from some explorative studies have not been confirmed in subsequent studies with higher numbers of animals or a priori defined hypotheses. Particularly relevant are some recent studies with negative outcomes that addressed effects of BPA on the brain, behavior, and the prostate in rodents for extrapolation to the human situation. The Committee came to the conclusion that rodent data can well be used as a basis for human risk evaluation. Currently published conjectures that rats are insensitive to estrogens compared to humans can be refuted. Data from toxicokinetics studies show that the half-life of BPA in adult human subjects is less than 2 hours and BPA is completely recovered in urine as BPA-conjugates. Tissue deconjugation

  1. Perfluoroalkyl substances exposure and thyroid hormones in humans: epidemiological observations and implications

    Directory of Open Access Journals (Sweden)

    Jung Eun Lee

    2017-03-01

    Full Text Available Thyroid hormones play crucial roles in normal neurodevelopment of fetus and child. Many chemicals can affect control and homeostasis of thyroid hormones, and eventually lead to various adverse health effects including neurodevelopmental disorders. Perfluoroalkyl substances (PFASs are among the thyroid disrupting chemicals that can be encountered among general human population. Due to their unique physicochemical characteristics, PFASs have been used as surfactants and surface coating materials in many applications. Therefore, PFASs have been frequently detected in humans and environment worldwide. In cross-sectional studies using nationally representative general human populations of United States, several PFASs have shown significant associations with thyroid hormones. Moreover, among pregnant women and their infants, not only major PFASs such as perfluorooctane sulfonic acid and perfluorooctanoic acid, but also those with shorter or longer carbon chains showed significant associations with thyroid hormones. Often demographic characteristics such as sex, age, and disease status appear to influence the associations between PFASs exposure and thyroid hormones. In general, major PFASs showed hypothyroidism effects among pregnant women and infants. As 8 carbon based PFASs have been phased out, those with shorter or longer carbon chains have been used in growing amount as replacement. However, only limited information is available for their occurrences and toxicity among humans. Further investigations on these substituting PFASs are required. In addition, efforts are warranted to identify sources of and mitigate exposure to these thyroid disrupting chemicals especially during pregnancy and early stages of life.

  2. Implications of human tissue studies

    International Nuclear Information System (INIS)

    Kathren, R.L.

    1986-10-01

    Through radiochemical analysis of voluntary tissue donations, the United States Transuranium and Uranium Registries are gaining improved understanding of the distribution and biokinetics of actinide elements in occupationally exposed persons. Evaluation of the first two whole body contributions to the Transuranium Registry revealed an inverse proportionality between actinide concentration and bone ash fraction. The analysis of a whole body with a documented 241 Am deposition indicated a significantly shorter half-time in liver and a greater fraction resident in the skeleton than predicted by existing models. Other studies of the Registries are designed to evaluate in vivo estimates of actinide deposition with those derived from postmortem tissue analysis, compare results of animal experiments with human data, and reviw histopathologic slides for tissue toxicity that might be attributable to exposure to uranium and the transuranic elements. The implications of these recent findings and other work of the Registries are discussed from the standpoint of their potential impact on biokinetic modeling, internal dose assessment, safety standards, and operational health physics practices

  3. Climate change impacts on human exposures to air pollution

    Science.gov (United States)

    This is an abstract for a presentations at the Annual Conference of the International Society on Exposure Science and Environmental Epidemiology. This presentation will serve as an introduction to the symposium.

  4. Campylobacter fetus infections in humans : exposure and disease

    NARCIS (Netherlands)

    Wagenaar, Jaap A; van Bergen, Marcel A P; Blaser, Martin J; Tauxe, Robert V; Newell, Diane G; van Putten, Jos P M

    Campylobacter fetus can cause intestinal illness and, occasionally, severe systemic infections. Infections mainly affect persons at higher risk, including elderly and immunocompromised individuals and those with occupational exposure to infected animals. Outbreaks are infrequent but have provided

  5. Dosimetric significance of cytogenetic examinations in human accidental over exposures

    International Nuclear Information System (INIS)

    Doloy-Biola, M.T.; Lego, R.; Ducatez, G.; Lepetit, J.; Bourguignon, M.

    1975-01-01

    The damage to 13 workers following accidental exposures was assessed from lymphocyte chromosomal aberrations, and the results compared with those supplied by physical dosimetry and the clinical syndromes [fr

  6. The Australian Work Exposures Study: Prevalence of Occupational Exposure to Formaldehyde.

    Science.gov (United States)

    Driscoll, Timothy R; Carey, Renee N; Peters, Susan; Glass, Deborah C; Benke, Geza; Reid, Alison; Fritschi, Lin

    2016-01-01

    The aims of this study were to produce a population-based estimate of the prevalence of work-related exposure to formaldehyde, to identify the main circumstances of exposure and to describe the use of workplace control measures designed to decrease those exposures. The analysis used data from the Australian Workplace Exposures Study, a nationwide telephone survey, which investigated the current prevalence and exposure circumstances of work-related exposure to 38 known or suspected carcinogens, including formaldehyde, among Australian workers aged 18-65 years. Using the web-based tool OccIDEAS, semi-quantitative information was collected about exposures in the current job held by the respondent. Questions were addressed primarily at tasks undertaken rather than about self-reported exposures. Of the 4993 included respondents, 124 (2.5%) were identified as probably being exposed to formaldehyde in the course of their work [extrapolated to 2.6% of the Australian working population-265 000 (95% confidence interval 221 000-316 000) workers]. Most (87.1%) were male. About half worked in technical and trades occupations. In terms of industry, about half worked in the construction industry. The main circumstances of exposure were working with particle board or plywood typically through carpentry work, building maintenance, or sanding prior to painting; with the more common of other exposures circumstances being firefighters involved in fighting fires, fire overhaul, and clean-up or back-burning; and health workers using formaldehyde when sterilizing equipment or in a pathology laboratory setting. The use of control measures was inconsistent. Workers are exposed to formaldehyde in many different occupational circumstances. Information on the exposure circumstances can be used to support decisions on appropriate priorities for intervention and control of occupational exposure to formaldehyde, and estimates of burden of cancer arising from occupational exposure to formaldehyde

  7. 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)

  8. The basal kinetic parameters of glycogen synthase in human myotube cultures are not affected by chronic high insulin exposure

    DEFF Research Database (Denmark)

    Gaster, M; Schrøder, H D; Handberg, A

    2001-01-01

    results show that chronic exposure of human myotubes to high insulin with or without high glucose did not affect the basal kinetic parameters but abolished the reactivity of GS to acute insulin stimulation. We suggest that insulin induced insulin resistance of GS is caused by a failure of acute insulin......There is no consensus regarding the results from in vivo and in vitro studies on the impact of chronic high insulin and/or high glucose exposure on acute insulin stimulation of glycogen synthase (GS) kinetic parameters in human skeletal muscle. The aim of this study was to evaluate the kinetic...... parameters of glycogen synthase activity in human myotube cultures at conditions of chronic high insulin combined or not with high glucose exposure, before and after a subsequent acute insulin stimulation. Acute insulin stimulation significantly increased the fractional activity (FV(0.1)) of GS, increased...

  9. Air Pollution Exposure Modeling for Health Studies | Science ...

    Science.gov (United States)

    Dr. Michael Breen is leading the development of air pollution exposure models, integrated with novel personal sensor technologies, to improve exposure and risk assessments for individuals in health studies. He is co-investigator for multiple health studies assessing the exposure and effects of air pollutants. These health studies include participants with asthma, diabetes, and coronary artery disease living in various U.S. cities. He has developed, evaluated, and applied novel exposure modeling and time-activity tools, which includes the Exposure Model for Individuals (EMI), GPS-based Microenvironment Tracker (MicroTrac) and Exposure Tracker models. At this seminar, Dr. Breen will present the development and application of these models to predict individual-level personal exposures to particulate matter (PM) for two health studies in central North Carolina. These health studies examine the association between PM and adverse health outcomes for susceptible individuals. During Dr. Breen’s visit, he will also have the opportunity to establish additional collaborations with researchers at Harvard University that may benefit from the use of exposure models for cohort health studies. These research projects that link air pollution exposure with adverse health outcomes benefit EPA by developing model-predicted exposure-dose metrics for individuals in health studies to improve the understanding of exposure-response behavior of air pollutants, and to reduce participant

  10. Risk assessment of human health from exposure to the discharged ballast water after full-scale electrolysis treatment.

    Science.gov (United States)

    Zhang, Nahui; Wang, Yidan; Xue, Junzeng; Yuan, Lin; Wang, Qiong; Liu, Liang; Wu, Huixian; Hu, Kefeng

    2016-06-01

    The presence of disinfection by-products (DBPs) releasing from ballast water management systems (BWMS) can cause a possible adverse effects on humans. The objectives of this study were to compute the Derived No Effect Levels (DNELs) for different exposure scenarios and to compare these levels with the exposure levels from the measured DBPs in treated ballast water. The risk assessment showed that when using animal toxicity data, all the DNELs values were approximately 10(3)-10(12) times higher than the exposure levels of occupational and general public exposure scenarios, indicating the level of risk was low (risk characterization ratios (RCRs) < 1). However, when using human data, the RCRs were higher than 1 for dichlorobromomethane and trichloromethane, indicating that the risk of adverse effects on human were significant. This implies that there are apparent discrepancies between risk characterization from animal and human data, which may affect the overall results. We therefore recommend that when appropriate, human data should be used in risk assessment as much as possible, although human data are very limited. Moreover, more appropriate assessment factors can be considered to be employed in estimating the DNELs for human when the animal data is selected as the dose descriptors. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. The EPA's human exposure research program for assessing cumulative risk in communities.

    Science.gov (United States)

    Zartarian, Valerie G; Schultz, Bradley D

    2010-06-01

    Communities are faced with challenges in identifying and prioritizing environmental issues, taking actions to reduce their exposures, and determining their effectiveness for reducing human health risks. Additional challenges include determining what scientific tools are available and most relevant, and understanding how to use those tools; given these barriers, community groups tend to rely more on risk perception than science. The U.S. Environmental Protection Agency's Office of Research and Development, National Exposure Research Laboratory (NERL) and collaborators are developing and applying tools (models, data, methods) for enhancing cumulative risk assessments. The NERL's "Cumulative Communities Research Program" focuses on key science questions: (1) How to systematically identify and prioritize key chemical stressors within a given community?; (2) How to develop estimates of exposure to multiple stressors for individuals in epidemiologic studies?; and (3) What tools can be used to assess community-level distributions of exposures for the development and evaluation of the effectiveness of risk reduction strategies? This paper provides community partners and scientific researchers with an understanding of the NERL research program and other efforts to address cumulative community risks; and key research needs and opportunities. Some initial findings include the following: (1) Many useful tools exist for components of risk assessment, but need to be developed collaboratively with end users and made more comprehensive and user-friendly for practical application; (2) Tools for quantifying cumulative risks and impact of community risk reduction activities are also needed; (3) More data are needed to assess community- and individual-level exposures, and to link exposure-related information with health effects; and (4) Additional research is needed to incorporate risk-modifying factors ("non-chemical stressors") into cumulative risk assessments. The products of this

  12. 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

  13. Polycyclic Aromatic Hydrocarbon (PAH Exposure and DNA Adduct Semi-Quantitation in Archived Human Tissues

    Directory of Open Access Journals (Sweden)

    M. Margaret Pratt

    2011-06-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs are combustion products of organic materials, mixtures of which contain multiple known and probable human carcinogens. PAHs occur in indoor and outdoor air, as well as in char-broiled meats and fish. Human exposure to PAHs occurs by inhalation, ingestion and topical absorption, and subsequently formed metabolites are either rendered hydrophilic and excreted, or bioactivated and bound to cellular macromolecules. The formation of PAH-DNA adducts (DNA binding products, considered a necessary step in PAH-initiated carcinogenesis, has been widely studied in experimental models and has been documented in human tissues. This review describes immunohistochemistry (IHC studies, which reveal localization of PAH-DNA adducts in human tissues, and semi-quantify PAH-DNA adduct levels using the Automated Cellular Imaging System (ACIS. These studies have shown that PAH-DNA adducts concentrate in: basal and supra-basal epithelium of the esophagus, cervix and vulva; glandular epithelium of the prostate; and cytotrophoblast cells and syncitiotrophoblast knots of the placenta. The IHC photomicrographs reveal the ubiquitous nature of PAH-DNA adduct formation in human tissues as well as PAH-DNA adduct accumulation in specific, vulnerable, cell types. This semi-quantative method for PAH-DNA adduct measurement could potentially see widespread use in molecular epidemiology studies.

  14. Characterizing the impact of projected changes in climate and air quality on human exposures to ozone.

    Science.gov (United States)

    Dionisio, Kathie L; Nolte, Christopher G; Spero, Tanya L; Graham, Stephen; Caraway, Nina; Foley, Kristen M; Isaacs, Kristin K

    2017-05-01

    The impact of climate change on human and environmental health is of critical concern. Population exposures to air pollutants both indoors and outdoors are influenced by a wide range of air quality, meteorological, behavioral, and housing-related factors, many of which are also impacted by climate change. An integrated methodology for modeling changes in human exposures to tropospheric ozone (O 3 ) owing to potential future changes in climate and demographics was implemented by linking existing modeling tools for climate, weather, air quality, population distribution, and human exposure. Human exposure results from the Air Pollutants Exposure Model (APEX) for 12 US cities show differences in daily maximum 8-h (DM8H) exposure patterns and levels by sex, age, and city for all scenarios. When climate is held constant and population demographics are varied, minimal difference in O 3 exposures is predicted even with the most extreme demographic change scenario. In contrast, when population is held constant, we see evidence of substantial changes in O 3 exposure for the most extreme change in climate. Similarly, we see increases in the percentage of the population in each city with at least one O 3 exposure exceedance above 60 p.p.b and 70 p.p.b thresholds for future changes in climate. For these climate and population scenarios, the impact of projected changes in climate and air quality on human exposure to O 3 are much larger than the impacts of changing demographics. These results indicate the potential for future changes in O 3 exposure as a result of changes in climate that could impact human health.

  15. Medical exposure to children - a pilot study

    International Nuclear Information System (INIS)

    Ingilizova, K.; Borisova, R.

    2008-01-01

    Patient dose assessment during medical exposure in paediatric diagnostic radiology is of highest importance in view of the greater radiation hazard to children compared to adults. It is conditioned by their higher sensitivity to ionizing radiation and their greater life expectancy. The risk of stochastic effects is several times greater for children than for adults. The attributive risk to children exposed to ionizing radiation during the first 10 years is 3 to 5 times greater than the risk to adults exposed between 30 and 40 years of age, and 6 to 7 times greater compared to the risk to adults exposed after their 50 year. The children dose distribution studies are carried out in order to elaborate national diagnostic reference levels. The dose assessment is complicated by the great variation in body size and anatomical features of children belonging to different age groups. There is a series of difficulties in the definition of image quality criteria and guidelines for good practice due to the dynamically changing body proportions and the anatomical features as a result of the active growth process from infancy through early childhood to adolescence. (author)

  16. Reconstruction of Exposure to m-Xylene from Human Biomonitoring Data Using PBPK Modelling, Bayesian Inference, and Markov Chain Monte Carlo Simulation

    Science.gov (United States)

    McNally, Kevin; Cotton, Richard; Cocker, John; Jones, Kate; Bartels, Mike; Rick, David; Price, Paul; Loizou, George

    2012-01-01

    There are numerous biomonitoring programs, both recent and ongoing, to evaluate environmental exposure of humans to chemicals. Due to the lack of exposure and kinetic data, the correlation of biomarker levels with exposure concentrations leads to difficulty in utilizing biomonitoring data for biological guidance values. Exposure reconstruction or reverse dosimetry is the retrospective interpretation of external exposure consistent with biomonitoring data. We investigated the integration of physiologically based pharmacokinetic modelling, global sensitivity analysis, Bayesian inference, and Markov chain Monte Carlo simulation to obtain a population estimate of inhalation exposure to m-xylene. We used exhaled breath and venous blood m-xylene and urinary 3-methylhippuric acid measurements from a controlled human volunteer study in order to evaluate the ability of our computational framework to predict known inhalation exposures. We also investigated the importance of model structure and dimensionality with respect to its ability to reconstruct exposure. PMID:22719759

  17. Reconstruction of Exposure to m-Xylene from Human Biomonitoring Data Using PBPK Modelling, Bayesian Inference, and Markov Chain Monte Carlo Simulation

    Directory of Open Access Journals (Sweden)

    Kevin McNally

    2012-01-01

    Full Text Available There are numerous biomonitoring programs, both recent and ongoing, to evaluate environmental exposure of humans to chemicals. Due to the lack of exposure and kinetic data, the correlation of biomarker levels with exposure concentrations leads to difficulty in utilizing biomonitoring data for biological guidance values. Exposure reconstruction or reverse dosimetry is the retrospective interpretation of external exposure consistent with biomonitoring data. We investigated the integration of physiologically based pharmacokinetic modelling, global sensitivity analysis, Bayesian inference, and Markov chain Monte Carlo simulation to obtain a population estimate of inhalation exposure to m-xylene. We used exhaled breath and venous blood m-xylene and urinary 3-methylhippuric acid measurements from a controlled human volunteer study in order to evaluate the ability of our computational framework to predict known inhalation exposures. We also investigated the importance of model structure and dimensionality with respect to its ability to reconstruct exposure.

  18. Analyses of human exposures to alpha-emitting radionuclides from nuclear fuel cycles

    International Nuclear Information System (INIS)

    Cuddihy, R.G.; McClellan, R.O.; Griffith, W.C.; Hoover, M.D.

    1977-01-01

    Human populations may potentially be exposed to alpha-emitting radionuclides released to the environment from a variety of activities associated with nuclear fuel cycles. Generally, the most important exposure pathway is by way of inhalation. This can occur soon after release of these substances or after they have been deposited on ground surfaces and resuspended with soil particles. Estimating the potential magnitude of these exposures is usually done through the use of mathematical models accounting for the dispersion of the released material through the environment and its uptake by people living near the nuclear facilities. Studies described in this paper suggest that these exposures can probably be estimated within a factor of 10 based upon our previous experience with measured human organ levels of other trace metals taken up from the environment. It should also be noted that variability among individuals within the population may result in a few percent accumulating more than 10 times the geometric mean of the internal organ radionuclide burdens

  19. Human exposure to environmental health concern by types of urban environment: The case of Tel Aviv

    International Nuclear Information System (INIS)

    Schnell, Izhak; Potchter, Oded; Yaakov, Yaron; Epstein, Yoram

    2016-01-01

    This study classifies urban environments into types characterized by different exposure to environmental risk factors measured by general sense of discomfort and Heart Rate Variability (HRV). We hypothesize that a set of environmental factors (micro-climatic, CO, noise and individual heart rate) that were measured simultaneously in random locations can provide a better understanding of the distribution of human exposure to environmental loads throughout the urban space than results calculated based on measurements from close fixed stations. We measured micro-climatic and thermal load, CO and noise, individual Heart Rate, Subjective Social Load and Sense of Discomfort (SD) were tested by questionnaire survey. The results demonstrate significant differences in exposure to environmental factors among 8 types of urban environments. It appears that noise and social load are the more significant environmental factors to enhance health risks and general sense of discomfort. - Highlights: • Indoor and outdoor environments were classified by exposure to health concern. • Measurements taken by people provide better knowledge than fixed stations. • Social stress and noise are more stressing factors than Thermal load and CO. • The most stressful places are crowded ones like markets etc. • Short visit in green spaces are effective in reducing levels of stress.

  20. [Difficulties of the methods for studying environmental exposure and neural tube defects].

    Science.gov (United States)

    Borja-Aburto, V H; Bermúdez-Castro, O; Lacasaña-Navarro, M; Kuri, P; Bustamante-Montes, P; Torres-Meza, V

    1999-01-01

    To discuss the attitudes in the assessment of environmental exposures as risk factors associated with neural tube defects, and to present the main risk factors studied to date. Environmental exposures have been suggested to have a roll in the genesis of birth defects. However, studies conducted in human populations have found difficulties in the design and conduction to show such an association for neural tube defects (anencephaly, espina bifida and encephalocele) because of problems raised from: a) the frequency measures used to compare time trends and communities, b) the classification of heterogeneous malformations, c) the inclusion of maternal, paternal and fetal factors as an integrated process and, d) the assessment of environmental exposures. Hypothetically both maternal and paternal environmental exposures can produce damage before and after conception by direct action on the embryo and the fetus-placenta complex. Therefore, in the assessment of environmental exposures we need to take into account: a) both paternal and maternal exposures; b) the critical exposure period, three months before conception for paternal exposures and one month around the conceptional period for maternal exposures; c) quantitatively evaluate environmental exposures when possible, avoiding a dichotomous classification; d) the use of biological markers of exposure is highly recommended as well as markers of genetic susceptibility.

  1. Lactate and pH evaluation in exhausted humans with prolonged TASER X26 exposure or continued exertion.

    Science.gov (United States)

    Ho, Jeffrey D; Dawes, Donald M; Cole, Jon B; Hottinger, Julie C; Overton, Kenneth G; Miner, James R

    2009-09-10

    Safety concerns about TASER Conducted Electrical Weapon (CEW) use and media reports of deaths after exposure have been expressed. CEWs are sometimes used on exhausted subjects to end resistance. The alternative is often a continued struggle. It is unclear if CEW use is metabolically different than allowing a continued struggle. We sought to determine if CEW exposure on exhausted humans caused worsening acidosis when compared with continued exertion. This was a prospective study of human volunteers recruited during a CEW training course. Volunteers were from several different occupations and represented a wide range of ages and body mass index characteristics. Medical histories, baseline pH and lactate values were obtained. Patients were assigned to one of four groups: 2 control groups consisting of Exertion only and CEW Exposure only, and the 2 experimental groups that were Exertion plus CEW Exposure and Exertion plus additional Exertion. Blood sampling occurred after Exertion and after any CEW exposure. This was repeated every 2-min until 20 min after protocol completion. Descriptive statistics were used to compare the four groups. The experimental groups and the control groups were compared individually at each time point using Wilcoxon rank sum tests. Lactate and pH association was assessed using multiple linear regression. Forty subjects were enrolled. There were no median pH or lactate differences between CEW Exposure groups at baseline, or between Exertion protocol groups immediately after completion. The CEW Exposure only group had higher pH and lower lactate values at all time points after exposure than the Exertion only group. After completing the Exertion protocol, there was no difference in the pH or lactate values between the continued Exertion group and the CEW Exposure group at any time points. Subjects who had CEW Exposure only had higher pH and lower lactate values than subjects who completed the Exertion protocol only. CEW exposure does not appear

  2. Intermittent, low dose carbon monoxide exposure enhances survival and dopaminergic differentiation of human neural stem cells

    DEFF Research Database (Denmark)

    Dreyer-Andersen, Nanna; Almeida, Ana Sofia; Jensen, Pia

    2018-01-01

    cells constitute an alternative source of cells for transplantation in Parkinson's disease, but efficient protocols for controlled dopaminergic differentiation need to be developed. Short-term, low-level carbon monoxide (CO) exposure has been shown to affect signaling in several tissues, resulting...... in both protection and generation of reactive oxygen species. The present study investigated the effect of CO produced by a novel CO-releasing molecule on dopaminergic differentiation of human neural stem cells. Short-term exposure to 25 ppm CO at days 0 and 4 significantly increased the relative content...... of β-tubulin III-immunoreactive immature neurons and tyrosine hydroxylase expressing catecholaminergic neurons, as assessed 6 days after differentiation. Also the number of microtubule associated protein 2-positive mature neurons had increased significantly. Moreover, the content of apoptotic cells...

  3. Genetic Polymorphisms in Organic Cation Transporter 1 Attenuates Hepatic Metformin Exposure in Humans

    DEFF Research Database (Denmark)

    Sundelin, E. I.O.; Gormsen, Lars C; Jensen, J. B.

    2017-01-01

    the transporter protein OCT1, affect the hepatic distribution of metformin in humans. We performed noninvasive 11C-metformin positron emission tomography (PET)/computed tomography (CT) to determine hepatic exposure in 12 subjects genotyped for variants in SLC22A1. Hepatic distribution of metformin...... was significantly reduced after oral intake in carriers of M420del and R61C variants in SLC22A1 without being associated with changes in circulating levels of metformin. Our data show that genetic polymorphisms in transporter proteins cause variation in hepatic exposure to metformin, and it demonstrates......Metformin has been used successfully to treat type 2 diabetes for decades. However, the efficacy of the drug varies considerably from patient to patient and this may in part be due to its pharmacokinetic properties. The aim of this study was to examine if common polymorphisms in SLC22A1, encoding...

  4. Human B cells fail to secrete type I interferons upon cytoplasmic DNA exposure.

    Science.gov (United States)

    Gram, Anna M; Sun, Chenglong; Landman, Sanne L; Oosenbrug, Timo; Koppejan, Hester J; Kwakkenbos, Mark J; Hoeben, Rob C; Paludan, Søren R; Ressing, Maaike E

    2017-11-01

    Most cells are believed to be capable of producing type I interferons (IFN I) as part of an innate immune response against, for instance, viral infections. In macrophages, IFN I is potently induced upon cytoplasmic exposure to foreign nucleic acids. Infection of these cells with herpesviruses leads to triggering of the DNA sensors interferon-inducible protein 16 (IFI16) and cyclic GMP-AMP (cGAMP) synthase (cGAS). Thereby, the stimulator of interferon genes (STING) and the downstream molecules TANK-binding kinase 1 (TBK1) and interferon regulatory factor 3 (IRF3) are sequentially activated culminating in IFN I secretion. Human gamma-herpesviruses, such as Epstein-Barr virus (EBV), exploit B cells as a reservoir for persistent infection. In this study, we investigated whether human B cells, similar to macrophages, engage the cytoplasmic DNA sensing pathway to induce an innate immune response. We found that the B cells fail to secrete IFN I upon cytoplasmic DNA exposure, although they express the DNA sensors cGAS and IFI16 and the signaling components TBK1 and IRF3. In primary human B lymphocytes and EBV-negative B cell lines, this deficiency is explained by a lack of detectable levels of the central adaptor protein STING. In contrast, EBV-transformed B cell lines did express STING, yet both these lines as well as STING-reconstituted EBV-negative B cells did not produce IFN I upon dsDNA or cGAMP stimulation. Our combined data show that the cytoplasmic DNA sensing pathway is dysfunctional in human B cells. This exemplifies that certain cell types cannot induce IFN I in response to cytoplasmic DNA exposure providing a potential niche for viral persistence. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Human recreational exposure to antibiotic resistant bacteria in coastal bathing waters.

    Science.gov (United States)

    Leonard, Anne F C; Zhang, Lihong; Balfour, Andrew J; Garside, Ruth; Gaze, William H

    2015-09-01

    large proportion of the population enjoys water sports. Millions of water sport sessions occurred in 2012 that were likely to have resulted in people ingesting E. coli resistant to a single class of antibiotics (3GCs). However, this is expected to be a significant underestimate of recreational exposure to all ARB in seawater. This is the first study to use volumes of water ingested during different water sports to estimate human exposure to ARB. Further work needs to be done to elucidate the health implications and clinical relevance of exposure to ARB in both marine and fresh waters in order to fully understand the risk to public health. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Human Exposure to Electromagnetic Fields from Parallel Wireless Power Transfer Systems.

    Science.gov (United States)

    Wen, Feng; Huang, Xueliang

    2017-02-08

    The scenario of multiple wireless power transfer (WPT) systems working closely, synchronously or asynchronously with phase difference often occurs in power supply for household appliances and electric vehicles in parking lots. Magnetic field leakage from the WPT systems is also varied due to unpredictable asynchronous working conditions. In this study, the magnetic field leakage from parallel WPT systems working with phase difference is predicted, and the induced electric field and specific absorption rate (SAR) in a human body standing in the vicinity are also evaluated. Computational results are compared with the restrictions prescribed in the regulations established to limit human exposure to time-varying electromagnetic fields (EMFs). The results show that the middle region between the two WPT coils is safer for the two WPT systems working in-phase, and the peripheral regions are safer around the WPT systems working anti-phase. Thin metallic plates larger than the WPT coils can shield the magnetic field leakage well, while smaller ones may worsen the situation. The orientation of the human body will influence the maximum magnitude of induced electric field and its distribution within the human body. The induced electric field centralizes in the trunk, groin, and genitals with only one exception: when the human body is standing right at the middle of the two WPT coils working in-phase, the induced electric field focuses on lower limbs. The SAR value in the lungs always seems to be greater than in other organs, while the value in the liver is minimal. Human exposure to EMFs meets the guidelines of the International Committee on Non-Ionizing Radiation Protection (ICNIRP), specifically reference levels with respect to magnetic field and basic restrictions on induced electric fields and SAR, as the charging power is lower than 3.1 kW and 55.5 kW, respectively. These results are positive with respect to the safe applications of parallel WPT systems working

  7. Human Exposure to Electromagnetic Fields from Parallel Wireless Power Transfer Systems

    Science.gov (United States)

    Wen, Feng; Huang, Xueliang

    2017-01-01

    The scenario of multiple wireless power transfer (WPT) systems working closely, synchronously or asynchronously with phase difference often occurs in power supply for household appliances and electric vehicles in parking lots. Magnetic field leakage from the WPT systems is also varied due to unpredictable asynchronous working conditions. In this study, the magnetic field leakage from parallel WPT systems working with phase difference is predicted, and the induced electric field and specific absorption rate (SAR) in a human body standing in the vicinity are also evaluated. Computational results are compared with the restrictions prescribed in the regulations established to limit human exposure to time-varying electromagnetic fields (EMFs). The results show that the middle region between the two WPT coils is safer for the two WPT systems working in-phase, and the peripheral regions are safer around the WPT systems working anti-phase. Thin metallic plates larger than the WPT coils can shield the magnetic field leakage well, while smaller ones may worsen the situation. The orientation of the human body will influence the maximum magnitude of induced electric field and its distribution within the human body. The induced electric field centralizes in the trunk, groin, and genitals with only one exception: when the human body is standing right at the middle of the two WPT coils working in-phase, the induced electric field focuses on lower limbs. The SAR value in the lungs always seems to be greater than in other organs, while the value in the liver is minimal. Human exposure to EMFs meets the guidelines of the International Committee on Non-Ionizing Radiation Protection (ICNIRP), specifically reference levels with respect to magnetic field and basic restrictions on induced electric fields and SAR, as the charging power is lower than 3.1 kW and 55.5 kW, respectively. These results are positive with respect to the safe applications of parallel WPT systems working

  8. Human Exposure to Electromagnetic Fields from Parallel Wireless Power Transfer Systems

    Directory of Open Access Journals (Sweden)

    Feng Wen

    2017-02-01

    Full Text Available The scenario of multiple wireless power transfer (WPT systems working closely, synchronously or asynchronously with phase difference often occurs in power supply for household appliances and electric vehicles in parking lots. Magnetic field leakage from the WPT systems is also varied due to unpredictable asynchronous working conditions. In this study, the magnetic field leakage from parallel WPT systems working with phase difference is predicted, and the induced electric field and specific absorption rate (SAR in a human body standing in the vicinity are also evaluated. Computational results are compared with the restrictions prescribed in the regulations established to limit human exposure to time-varying electromagnetic fields (EMFs. The results show that the middle region between the two WPT coils is safer for the two WPT systems working in-phase, and the peripheral regions are safer around the WPT systems working anti-phase. Thin metallic plates larger than the WPT coils can shield the magnetic field leakage well, while smaller ones may worsen the situation. The orientation of the human body will influence the maximum magnitude of induced electric field and its distribution within the human body. The induced electric field centralizes in the trunk, groin, and genitals with only one exception: when the human body is standing right at the middle of the two WPT coils working in-phase, the induced electric field focuses on lower limbs. The SAR value in the lungs always seems to be greater than in other organs, while the value in the liver is minimal. Human exposure to EMFs meets the guidelines of the International Committee on Non-Ionizing Radiation Protection (ICNIRP, specifically reference levels with respect to magnetic field and basic restrictions on induced electric fields and SAR, as the charging power is lower than 3.1 kW and 55.5 kW, respectively. These results are positive with respect to the safe applications of parallel WPT systems

  9. The diesel exhaust in miners study: II. Exposure monitoring surveys and development of exposure groups.

    NARCIS (Netherlands)

    Coble, J.B.; Stewart, P.A.; Vermeulen, R.; Yereb, D.; Stanevich, R.; Blair, A.; Silverman, D.T.; Attfield, M.

    2010-01-01

    Air monitoring surveys were conducted between 1998 and 2001 at seven non-metal mining facilities to assess exposure to respirable elemental carbon (REC), a component of diesel exhaust (DE), for an epidemiologic study of miners exposed to DE. Personal exposure measurements were taken on workers in a

  10. Impact assessment on the human exposure to environmental radiation

    International Nuclear Information System (INIS)

    Kim, Y.J.; Lee, K.S.; Kim, J.B.; Chun, K.J.; Kim, S.R.; Chung, K.H.

    1983-01-01

    1. The Terrestrial Ecosystem in the Vicinity of Kori Nuclear Power Plant. In order to evaluate the effects of radiation or radionuclides released from the nuclear power plants on human population, field surveys on the terrestrial ecosystem such as the fauna and flora in the vicinity within 15 km from the Kori nuclear power plant were carried out. 2. Level of radionuclides, Metabolism and Chromosome Aberration. The present study was undertaken with the purpose for evaluating 1) the level of Sr-90 in the Korean vertebra, 2) the metabolism of Sr-90 in the rats, 3) the levels of Sr-90 and Cs-137 in the pine needles (Pinus densiflora), 4) the level of Sr-90 in the frogs (Rana nigromaculata) and 5) the radiation effects by internal Sr-90 on the bone marrow. (Author)

  11. Evaluation of AirGIS: a GIS-based air pollution and human exposure modelling system

    DEFF Research Database (Denmark)

    Ketzel, Matthias; Berkowicz, Ruwim; Hvidberg, Martin

    2011-01-01

    This study describes in brief the latest extensions of the Danish Geographic Information System (GIS)-based air pollution and human exposure modelling system (AirGIS), which has been developed in Denmark since 2001 and gives results of an evaluation with measured air pollution data. The system...... shows, in general, a good performance for both long-term averages (annual and monthly averages), short-term averages (hourly and daily) as well as when reproducing spatial variation in air pollution concentrations. Some shortcomings and future perspectives of the system are discussed too....

  12. 77 FR 52025 - Notification of a Public Teleconference of the Science Advisory Board; Exposure and Human Health...

    Science.gov (United States)

    2012-08-28

    ... Science Advisory Board; Exposure and Human Health Committee AGENCY: Environmental Protection Agency (EPA... Office announces a public teleconference of the SAB Exposure and Human Health Committee to discuss its... hereby given that the SAB Exposure and Human Health Committee (EHHC) will hold a public teleconference to...

  13. Co-ordinated research programme on assessment of environmental exposure to mercury in selected human populations as studied by nuclear and other techniques. Report on the second research co-ordination meeting held in Kuala Lumpur, Malaysia, 24-28 August 1992

    International Nuclear Information System (INIS)

    1992-01-01

    A Coordinated Research Programme (CRP) on assessment of environmental exposure to mercury in selected human populations as studied by nuclear and other techniques was initiated by the IAEA in 1990 in collaboration with WHO. The purpose of this CRP is to promote national and regional studies to evaluate the exposure of selected population groups to mercury and methylmercury and to estimate potential health risks in these groups. The programme is focused on the analysis of human head hair for the determination of mercury and methylmercury. This CRP has two main components: (i) identifying population groups that are at risk, and (ii) studying health effects in the exposed persons, particularly pregnant women and the babies born to them. This report contains the discussions held during the second Research Co-ordination Meeting (RCM) for the CRP which took place in Kuala Lumpur, Malaysia, under the sponsorship of the University Kebangsaan Malaysia and papers presented at this meeting. Refs, figs and tabs

  14. Global Gene Expression Profiling of Human Genome Following Exposure to Sarin and Soman

    International Nuclear Information System (INIS)

    Gopalakrishnakone, P.; Pachiappan, A.; Srinivasan, K. N.; Loke, W. K.; Lee, F. K.

    2007-01-01

    Toxicogenomics merges genomics with toxicology is a rapidly expanding field on the assumption that the transcriptional responses of cells to different toxic exposure are sufficiently distinct robust and reproducible to discriminate toxin from different families/classes which can be called as 'fingerprints' or 'Atlases'. In this study chemical weapons sarin was studied in a time and dose dependent manner after exposure to human neuroblastoma cell line. (Sarin or GB) exerts its effect through inhibition of acetylcholinesterase activity and induction of delayed neurotoxicity in a dose [EC 50 50 ppm, (around 372.4 μM)] and time-dependent manner. The effect and/or the mechanism of single or repeated exposures to GB, however, are less clear and yet to be explored at cellular level. The present study aims to scrutinize, the global gene expression profile following sarin toxicity in neuronal cells using Affymetrix-GeneChips. A tim-course study on the effect of a single (3 or 24h) or repeated (24 or 48h) doses of sarin (5ppm) on SHSY5Y cells was carried out. Using GeneSpring (PCA) analysis, 550 genes whose expression was significantly (p less than 0.01) altered by at least 2.5-fold, were selected. The results indicate that the low-level single dose exposure do not always parallel acute toxicity, but can cause a reversible down-regulation of genes and a range of anti-cholinesterase effects. In contrast, repeated doses produced persistent irreversible down-regulation of genes related to neurodegenerative mechanism at 48h. Real-time PCR and western blot analysis confirmed the reduced expression of presenilin 1 (TMP21), 2 and dopa.decarboxylase (DDC) mRNA and proteins. Besides providing an in vitro experimental model for studies on the neuropathophysiology and brain cells this investigation indicate possible mechanisms by which sarin could mediate neuro-degeneration. A comparison will be made with similar study with soman. (author)

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

    NARCIS (Netherlands)

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

    2010-01-01

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

  16. In vivo plasma concentration for lindane after 6 hour exposure in human skin

    Data.gov (United States)

    U.S. Environmental Protection Agency — Dataset is a time course description of lindane disappearance in blood plasma after dermal exposure in human volunteers. This dataset is associated with the...

  17. Probabilistic estimation of residential air exchange rates for population-based human exposure modeling

    Science.gov (United States)

    Residential air exchange rates (AERs) are a key determinant in the infiltration of ambient air pollution indoors. Population-based human exposure models using probabilistic approaches to estimate personal exposure to air pollutants have relied on input distributions from AER meas...

  18. A Quantitative ADME-base Tool for Exploring Human Exposure to Consumer Product Ingredients

    Science.gov (United States)

    Exposure to a wide range of chemicals through our daily habits and routines is ubiquitous and largely unavoidable within modern society. The potential for human exposure, however, has not been quantified for the vast majority of chemicals with wide commercial use. Creative advanc...

  19. In Vivo Lipopolysaccharide Exposure of Human Blood Leukocytes Induces Cross-Tolerance to Multiple TLR Ligands

    NARCIS (Netherlands)

    de Vos, Alex F.; Pater, Jennie M.; van den Pangaart, Petra S.; de Kruif, Martijn D.; van 't Veer, Cornelis; van der Poll, Tom

    2009-01-01

    In vitro and in vivo experiments in mice have shown that exposure of cells to the TLR4 ligand LPS induces tolerance toward a second exposure to LPS and induces cross-tolerance to certain other TLR ligands. Recently, we found that LPS tolerance in experimental human endotoxemia and Gram-negative

  20. Human Embryonic Stem Cell Responses to Ionizing Radiation Exposures: Current State of Knowledge and Future Challenges

    Directory of Open Access Journals (Sweden)

    Mykyta V. Sokolov

    2012-01-01

    Full Text Available Human embryonic stem cells, which are derived from the inner cell mass of the blastocyst, have become an object of intense study over the last decade. They possess two unique properties that distinguish them from many other cell types: (i the ability to self-renew indefinitely in culture under permissive conditions, and (ii the pluripotency, defined as the capability of giving rise to all cell types of embryonic lineage under the guidance of the appropriate developmental cues. The focus of many recent efforts has been on the elucidating the signaling pathways and molecular networks operating in human embryonic stem cells. These cells hold great promise in cell-based regenerative therapies, disease modeling, drug screening and testing, assessing genotoxic and mutagenic risks associated with exposures to a variety of environmental factors, and so forth. Ionizing radiation is ubiquitous in nature, and it is widely used in diagnostic and therapeutic procedures in medicine. In this paper, our goal is to summarize the recent progress in understanding how human embryonic stem cells respond to ionizing radiation exposures, using novel methodologies based on “omics” approaches, and to provide a critical discussion of what remains unknown; thus proposing a roadmap for the future research in this area.

  1. Exposure of Extremely-Low Frequency (ELF magnetic field may cause human cancer

    Directory of Open Access Journals (Sweden)

    Daryoush Shahbazi-Gahrouei

    2017-01-01

    Full Text Available Introduction: Chronic exposure of non-ionizing extremely low-frequency magnetic fields (ELF-EMF is considered as a health hazard due to its adverse effects on human body such as generation of any type of cancer. Stem cells are appropriate models to assess the effects of ELF-EMF on other cell lines and human beings. Materials and methods: Adipose tissue has been known as source of multi potent stromal human mesenchymal stem cells (MSCs which can be obtained in less invasive method and in large amounts; so adipose-derived stem cells (ADSCs were used in this study. Effect of ELF-EMF (intensities of 0.5 and 1 mT and 50 Hz on proliferation rate of hADSCs was assessed in 20 and 40 min per day for 7 days. Trypan blue assay was performed to assess cell proliferation rate. Result: The results shown that 0.5 and 1 mT magnetic fields can promote the proliferation rate of adipose derived hMSCs according to the duration of exposure. Conclusion: These outcomes could approve the effect of ELF-EMF on cancer induction; although the effective mechanisms in this process are still unknown.

  2. Separation of uncertainty and interindividual variability in human exposure modeling.

    NARCIS (Netherlands)

    Ragas, A.M.J.; Brouwer, F.P.E.; Buchner, F.L.; Hendriks, H.W.; Huijbregts, M.A.J.

    2009-01-01

    The NORMTOX model predicts the lifetime-averaged exposure to contaminants through multiple environmental media, that is, food, air, soil, drinking and surface water. The model was developed to test the coherence of Dutch environmental quality objectives (EQOs). A set of EQOs is called coherent if

  3. Aquatic Sentinels Forecasting Human Exposure To Emerging Contaminants

    Science.gov (United States)

    Most of us have heard the axiom, “canary in the coal mine”. These melodious exposure indicators - a necessity in U.K. mines well into the 20th century - were especially sensitive to methane and carbon monoxide gases, and would cease singing (and oftentimes die) at le...

  4. Strategies for estimating human exposure to mycotoxins via food

    NARCIS (Netherlands)

    Nijs, De M.; Mengelers, M.J.B.; Boon, P.E.; Heyndrickx, E.; Hoogenboom, L.A.P.; Lopez, P.; Mol, H.G.J.

    2016-01-01

    In this review, five strategies to estimate mycotoxin exposure of a (sub-)population via food, including data collection, are discussed with the aim to identify the added values and limitations of each strategy for risk assessment of these chemicals. The well-established point estimate, observed

  5. Human health effects of dust exposure in anmial confinement buildings

    NARCIS (Netherlands)

    Iversen, M.; Kirychuk, S.; Drost, H.; Jacobson, L.

    2001-01-01

    Work in swine and poultry units is associated with exposure to significant levels of organic dust and endotoxins with the highest concentrations found in poultry houses, whereas values found in dairy and in cattle farming are much lower. Corresponding to this is an excess of work-related respiratory

  6. FDTD assessment of human exposure to electromagnetic fields from WiFi and bluetooth devices in some operating situations.

    Science.gov (United States)

    Martínez-Búrdalo, M; Martín, A; Sanchis, A; Villar, R

    2009-02-01

    In this work, the numerical dosimetry in human exposure to the electromagnetic fields from antennas of wireless devices, such as those of wireless local area networks (WLAN) access points or phone and computer peripherals with Bluetooth antennas, is analyzed with the objective of assessing guidelines compliance. Several geometrical configurations are considered to simulate possible exposure situations of a person to the fields from WLAN or Bluetooth antennas operating at 2400 MHz. The exposure to radiation from two sources of different frequencies when using a 1800 MHz GSM mobile phone connected via Bluetooth with a hands-free car kit is also considered. The finite-difference time-domain (FDTD) method is used to calculate electric and magnetic field values in the vicinity of the antennas and specific absorption rates (SAR) in a high-resolution model of the human head and torso, to be compared with the limits from the guidelines (reference levels and basic restrictions, respectively). Results show that the exposure levels in worst-case situations studied are lower than those obtained when analyzing the exposure to mobile phones, as could be expected because of the low power of the signals and the distance between the human and the antennas, with both field and SAR values being far below the limits established by the guidelines, even when considering the combined exposure to both a GSM and a Bluetooth antenna. Copyright 2008 Wiley-Liss, Inc.

  7. Modeling human exposure to hazardous-waste sites: a question of completeness

    International Nuclear Information System (INIS)

    Daniels, J.I.; McKone, T.E.

    1991-01-01

    In risk analysis, we use human-exposure assessments to translate contaminant sources into quantitative estimates of the amount of contaminant that comes in contact with human-environment boundaries, that is, the lungs, the gastrointestinal tract, and the skin surface of individuals within a specified population. An assessment of intake requires that we determine how much crosses these boundaries. Exposure assessments often rely implicitly in the assumption that exposure can be linked by simple parameters to ambient concentration in air, water, and soil. However, more realistic exposure models require that we abandon such simple assumptions. To link contaminant concentrations in water, air, or soil with potential human intakes, we constrict pathway-exposure factors (PEFs). For each PEF we combine information in environmental partitioning as well as human anatomy, physiology, and patterns into an algebraic term that converts concentrations of contaminants (in mg/L water, mg/m 3 air, and mg/kg soil) into a daily intake per unit body weight in mg/kg-d for a specific rout of exposure such as inhalation, ingestion, or dermal uptake. Using examples involving human exposure to either a radionuclide (tritium, 3 H) or a toxic organic chemical (tetrachloroethylene, PCE) in soil, water, and air, we illustrate the use of PEFs and consider the implications for risk assessment. (au)

  8. Effects of butyltin exposures on MAP kinase dependent transcription regulators in human natural killer cells

    Science.gov (United States)

    Person, Rachel J.; Whalen, Margaret M.

    2010-01-01

    Natural Killer (NK) cells are a major immune defense mechanism against cancer development and viral infection. The butyltins (BTs), tributyltin (TBT) and dibutyltin (DBT) have been widely used in industrial and other applications and significantly contaminate the environment. Both TBT and DBT have been detected in human blood. These compounds inhibit the lytic and binding function of human NK cells and thus could increase the incidence of cancer and viral infections. Butyltin (BT)-induced loss of NK function is accompanied by activation of mitogen activated protein kinases (MAPKs) and decreases in expression of cell-surface and cytolytic proteins. MAPKs activate components of the transcription regulator AP-1 and activate the transcription regulator Elk-1. Based on the fact that BTs activate MAPKs and alter protein expression, the current study examined the effect of BT exposures on the levels and phosphorylation states of the components of AP-1 and the phosphorylation state of Elk-1. Exposure to 300 nM TBT for 10 min increased the phosphorylation of c-Jun in NK cells. 1 h exposures to 300 nM and 200 nM TBT increased the phosphorylation and overall level of c-Jun. During a 300 nM treatment with TBT for 1 h the binding activity of AP-1 was significantly decreased. There were no significant alterations of AP-1 components or of Elk-1 with DBT exposures. Thus, it appears that TBT-induced alterations on phosphorylation, total levels and binding activity of c-Jun might contribute to, but are not fully responsible for, TBT-induced alterations of NK protein expression. PMID:20370538

  9. Limited infection upon human exposure to a recombinant raccoon pox vaccine vector

    Science.gov (United States)

    Rocke, T.E.; Dein, F.J.; Fuchsberger, M.; Fox, B.C.; Stinchcomb, D.T.; Osorio, J.G.

    2004-01-01

    A laboratory accident resulted in human exposure to a recombinant raccoon poxvirus (RCN) developed as a vaccine vector for antigens of Yersinia pestis for protection of wild rodents (and other animals) against plague. Within 9 days, the patient developed a small blister that healed within 4 weeks. Raccoon poxvirus was cultured from the lesion, and the patient developed antibody to plague antigen (F1) and RCN. This is the first documented case of human exposure to RCN.

  10. Limited infection upon human exposure to a recombinant raccoon pox vaccine vector.

    Science.gov (United States)

    Rocke, Tonie E; Dein, F Joshua; Fuchsberger, Martina; Fox, Barry C; Stinchcomb, Dan T; Osorio, Jorge E

    2004-07-29

    A laboratory accident resulted in human exposure to a recombinant raccoon poxvirus (RCN) developed as a vaccine vector for antigens of Yersinia pestis for protection of wild rodents (and other animals) against plague. Within 9 days, the patient developed a small blister that healed within 4 weeks. Raccoon poxvirus was cultured from the lesion, and the patient developed antibody to plague antigen (F1) and RCN. This is the first documented case of human exposure to RCN.

  11. CONTROLLED EXPOSURES OF HUMAN VOLUNTEERS TO DIESEL ENGINE EXHAUST: BIOMARKERS OF EXPOSURE AND HEALTH OUTCOMES

    Science.gov (United States)

    Combustion of diesel fuel contributes to ambient air pollutant fine particulate matter (PM) and gases. Fine PM exposure has been associated with increased mortality due to adverse cardiac events, and morbidity, such as increased hospitalization for asthma symptoms and lung infect...

  12. Estimation of dose and exposure at sentinel node study

    International Nuclear Information System (INIS)

    Skopljak, A.; Kucukalic-Selimovic, E.; Beslic, N.; Begic, A.; Begovic-Hadzimuratovic, S.; Drazeta, Z.; Beganovic, A.

    2005-01-01

    The purpose of this study was to estimate the dose end exposure in staff involved in sentinel node procedure for breast cancer patients. The Institute of Nuclear Medicine in Sarajevo uses a protocol for lymphoscintigraphy of the sentinel node whereby 13 MBq of 9 9mT c nanocoll are used. In this study, we measured radiation doses and exposure of a nuclear medicine physician and a technologist, as well as a surgeon performing sentinel node lymphoscintigraphy and biopsy. Dose and exposure were calculated using the equation in which we have gamma constant for 9 9mT c. Calculations were made for different times of exposure and distance. In Table 1. we estimated the dose and exposure during sentinel node study. Radiation levels were very low and the most exposed hospital staff performing sentinel node study were nuclear medicine physicians. The doses on the hands of surgeons were negligible 8 hours after exposure.(author)

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

    International Nuclear Information System (INIS)

    Eggink, G.J.; Slaper, H.

    1992-01-01

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

  14. Assessment of human exposure to fumonisin B1

    NARCIS (Netherlands)

    Nijs, M. de; Egmond, H.P. van; Nauta, M.; Rombouts, F.M.; Notermans, S.H.W.

    1998-01-01

    Fumonisin B1 is currently regarded as the most significant mycotoxin produced by Fusarium spp. It has carcinogenic properties and may play a role in the etiology of human esophageal cancer. The human population is exposed to fumonisin B1 primarily by intake of fumonisin B1-contaminated maize. Maize

  15. Individual differences in the effects of mobile phone exposure on human sleep: rethinking the problem.

    Science.gov (United States)

    Loughran, Sarah P; McKenzie, Raymond J; Jackson, Melinda L; Howard, Mark E; Croft, Rodney J

    2012-01-01

    Mobile phone exposure-related effects on the human electroencephalogram (EEG) have been shown during both waking and sleep states, albeit with slight differences in the frequency affected. This discrepancy, combined with studies that failed to find effects, has led many to conclude that no consistent effects exist. We hypothesised that these differences might partly be due to individual variability in response, and that mobile phone emissions may in fact have large but differential effects on human brain activity. Twenty volunteers from our previous study underwent an adaptation night followed by two experimental nights in which they were randomly exposed to two conditions (Active and Sham), followed by a full-night sleep episode. The EEG spectral power was increased in the sleep spindle frequency range in the first 30 min of non-rapid eye movement (non-REM) sleep following Active exposure. This increase was more prominent in the participants that showed an increase in the original study. These results confirm previous findings of mobile phone-like emissions affecting the EEG during non-REM sleep. Importantly, this low-level effect was also shown to be sensitive to individual variability. Furthermore, this indicates that previous negative results are not strong evidence for a lack of an effect and, given the far-reaching implications of mobile phone research, we may need to rethink the interpretation of results and the manner in which research is conducted in this field. Copyright © 2011 Wiley Periodicals, Inc.

  16. 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.

  17. A biokinetic model of inhaled Cm compounds in dogs: Application to human exposure data

    International Nuclear Information System (INIS)

    Guilmette, R.A.; Mewhinney, J.A.

    1989-01-01

    Curium isotopes are major by-products in irradiated nuclear reactor fuel and comprise a significant fraction of the alpha-emitting radionuclide inventory. Although little use is currently being made of purified Cm sources, such usage is possible if reprocessing of spent fuel becomes feasible. Because little information is available on the biokinetics and dosimetry of inhaled Cm compounds, a study was conducted in which adult beagle dogs received a single inhalation exposure to either a monodisperse aerosol of 244Cm2O3 (1.4 micron activity median aerodynamic diameter [AMAD]; sigma g = 1.16) or a polydisperse aerosol of 244Cm (NO3)3 (1.1 micron AMAD; sigma g = 1.74). At times ranging from 4 h to 2 y after exposure, animals were sacrificed and their tissues analyzed for Cm content. The data describing the uptake and retention of 244Cm in the different organs and tissues and the measured rates of excretion of these dogs formed the basis on which a biokinetic model of Cm metabolism was constructed. This Cm model was based on a previously published model of the biokinetics of 241Am that was shown to be applicable to data from human cases of inhalation exposure to 241Am aerosols. This Cm model was found to be adequate to describe the biological distribution of Cm in dogs and was also applied to the sparse data from humans. Reasonable agreement was found between the model predictions for lung retention of Cm and for urinary excretion patterns in humans

  18. Activity Patterns and Pollution Exposure. A Case Study of Melbourne

    International Nuclear Information System (INIS)

    Marquez, L.; Smith, N.; Trinidad, G.; Guo, J.

    2001-01-01

    In recent times there has been increasing interest in modelling policies to limit impacts of air pollution due to motor vehicles. Impacts of air pollution on human health and comfort depend on the relationship between the distribution of pollutants and the spatial distribution of the urban population. As emissions, weather conditions and the location of the population vary with time of day, day of month and season of the year, the problem is complex. Travel demand models with activity-based approaches and a focus on the overall structure of activity/travel relations, not only spatially, but temporally can make a valuable contribution. They are often used to estimate emissions due to the travel patterns of city populations but may equally be used to provide distributions of urban populations during the day. A case study for Melbourne, Australia demonstrates the use of activity data in the estimation of population exposure. Additionally the study shows some marked differences in activity between seasons and even greater the differences in effect of that activity on exposure to air pollution. Numbers of cities will have seasonal pollutant patterns similar to Melbourne and others will benefit from exploring such patterns

  19. Influence of radiation exposure on our society and epidemiological study

    International Nuclear Information System (INIS)

    Yoshimoto, Yasuhiko

    1997-01-01

    A brief epidemiological review of risk assessment of radiation was discussed with respect to two periods; before and after the establishment of the United Nations Scientific Committee on the Effects of Atomic Radiation. Selected topics were the studies of atomic bomb survivors and people living in the contaminated areas due to Chernobyl nuclear power plant accident. An ethical view to ensure that potential social benefits of epidemiology are maximized was emphasized as well as a scientific view. On the other hand it should be recognized that there are the limitations of epidemiological studies on the basis of the observations on man in which the animal-experimental setting generally cannot be controlled over. Informing people about the professional confidence and caution of radiation exposure is needed to resolve social concern associated with low dose, low dose rate of radiation. Also there are guidelines for the investigation of clusters of adverse health events. In the future an appropriate strategy for decontamination might be expected to unusual radiation exposure as a consequence of a nuclear power plant accident. Justification for the implementations can be determined only through the assessment of the effects both on the environment and health of humans after the accident. (author)

  20. Co-exposure to nickel and cobalt chloride enhances cytotoxicity and oxidative stress in human lung epithelial cells.

    Science.gov (United States)

    Patel, Eshan; Lynch, Christine; Ruff, Victoria; Reynolds, Mindy

    2012-02-01

    Nickel and cobalt are heavy metals found in land, water, and air that can enter the body primarily through the respiratory tract and accumulate to toxic levels. Nickel compounds are known to be carcinogenic to humans and animals, while cobalt compounds produce tumors in animals and are probably carcinogenic to humans. People working in industrial and manufacturing settings have an increased risk of exposure to these metals. The cytotoxicity of nickel and cobalt has individually been demonstrated; however, the underlying mechanisms of co-exposure to these heavy metals have not been explored. In this study, we investigated the effect of exposure of H460 human lung epithelial cells to nickel and cobalt, both alone and in combination, on cell survival, apoptotic mechanisms, and the generation of reactive oxygen species and double strand breaks. For simultaneous exposure, cells were exposed to a constant dose of 150 μM cobalt or nickel, which was found to be relatively nontoxic in single exposure experiments. We demonstrated that cells exposed simultaneously to cobalt and nickel exhibit a dose-dependent decrease in survival compared to the cells exposed to a single metal. The decrease in survival was the result of enhanced caspase 3 and 7 activation and cleavage of poly (ADP-ribose) polymerase. Co-exposure increased the production of ROS and the formation of double strand breaks. Pretreatment with N-acetyl cysteine alleviated the toxic responses. Collectively, this study demonstrates that co-exposure to cobalt and nickel is significantly more toxic than single exposure and that toxicity is related to the formation of ROS and DSB. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Human exposure to herpesvirus B-seropositive macaques, Bali, Indonesia.

    Science.gov (United States)

    Engel, Gregory A; Jones-Engel, Lisa; Schillaci, Michael A; Suaryana, Komang Gde; Putra, Artha; Fuentes, Agustin; Henkel, Richard

    2002-08-01

    Herpesvirus B (Cercopithecine herpesvirus 1) has been implicated as the cause of approximately 40 cases of meningoencephalitis affecting persons in direct or indirect contact with laboratory macaques. However, the threat of herpesvirus B in nonlaboratory settings worldwide remains to be addressed. We investigated the potential for exposure to herpesvirus B in workers at a "monkey forest" (a temple that has become a tourist attraction because of its monkeys) in Bali, Indonesia. In July 2000, 105 workers at the Sangeh Monkey Forest in Central Bali were surveyed about contact with macaques (Macaca fascicularis). Nearly half of those interviewed had either been bitten or scratched by a macaque. Prevalence of injury was higher in those who fed macaques. Serum from 31 of 38 Sangeh macaques contained antibodies to herpesvirus B. We conclude that workers coming into contact with macaques at the Sangeh Monkey Forest are at risk for exposure to herpesvirus B.

  2. Controlled human exposure to indoor air, dust, and ozone; XDOZ

    DEFF Research Database (Denmark)

    Elholm, Grethe; Bønløkke, Jakob; Schlünssen, Vivi

    2017-01-01

    . All participants were subjected to four different exposure scenarios in the climate chamber.Exp. 1: Dust (250 – 300 µg/m3)Exp. 2: Ozone (100 ppb)Exp. 3: Dust (250 – 300 µg/m3) + ozone (100 ppb)Exp. 4: Filtered air (<20µg/m3)The exposure time was 5½ hours for each session.The health effects were...... evaluated at baseline and specific follow-up times in relation to selected respiratory and cardiovascular outcomes, such as; nasal volume, exhaled nitric oxide (FENO), spirometry (FEV1 and FVC), exhaled breath condensate (EBC), nasal lavage, blood samples, EndoPat. Questionnaires were used for assessment...

  3. Low dose perfluorooctanoate exposure promotes cell proliferation in a human non-tumor liver cell line

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongxia; Cui, Ruina [Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 (China); Guo, Xuejiang [State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 210029 (China); Hu, Jiayue [Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 (China); Dai, Jiayin, E-mail: daijy@ioz.ac.cn [Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 (China)

    2016-08-05

    Highlights: • Differential expression of proteins induced by PFOA in HL-7702 was identified. • Most of the differentially expressed proteins are related to cell proliferation. • A low dose of PFOA stimulates HL-7702 cell proliferation. • A high dose of PFOA inhibits HL-7702 cell proliferation. - Abstract: Perfluorooctanoate (PFOA) is a well-known persistent organic pollutant widely found in the environment, wildlife and humans. Medical surveillance and experimental studies have investigated the potential effects of PFOA on human livers, but the hepatotoxicity of PFOA on humans and its underlying mechanism remain to be clarified. We exposed a human liver cell line (HL-7702) to 50 μM PFOA for 48 h and 96 h, and identified 111 significantly differentially expressed proteins by iTRAQ analysis. A total of 46 proteins were related to cell proliferation and apoptosis. Through further analysis of the cell cycle, apoptosis and their related proteins, we found that low doses of PFOA (50–100 μM) promoted cell proliferation and numbers by promoting cells from the G1 to S phases, whereas high doses of PFOA (200–400 μM) led to reduced HL-7702 cell numbers compared with that of the control mainly due to cell cycle arrest in the G0/G1 phase. To our knowledge, this is the first report on the promotion of cell cycle progression in human cells following PFOA exposure.

  4. Low dose perfluorooctanoate exposure promotes cell proliferation in a human non-tumor liver cell line

    International Nuclear Information System (INIS)

    Zhang, Hongxia; Cui, Ruina; Guo, Xuejiang; Hu, Jiayue; Dai, Jiayin

    2016-01-01

    Highlights: • Differential expression of proteins induced by PFOA in HL-7702 was identified. • Most of the differentially expressed proteins are related to cell proliferation. • A low dose of PFOA stimulates HL-7702 cell proliferation. • A high dose of PFOA inhibits HL-7702 cell proliferation. - Abstract: Perfluorooctanoate (PFOA) is a well-known persistent organic pollutant widely found in the environment, wildlife and humans. Medical surveillance and experimental studies have investigated the potential effects of PFOA on human livers, but the hepatotoxicity of PFOA on humans and its underlying mechanism remain to be clarified. We exposed a human liver cell line (HL-7702) to 50 μM PFOA for 48 h and 96 h, and identified 111 significantly differentially expressed proteins by iTRAQ analysis. A total of 46 proteins were related to cell proliferation and apoptosis. Through further analysis of the cell cycle, apoptosis and their related proteins, we found that low doses of PFOA (50–100 μM) promoted cell proliferation and numbers by promoting cells from the G1 to S phases, whereas high doses of PFOA (200–400 μM) led to reduced HL-7702 cell numbers compared with that of the control mainly due to cell cycle arrest in the G0/G1 phase. To our knowledge, this is the first report on the promotion of cell cycle progression in human cells following PFOA exposure.

  5. Critical elements for human health risk assessment of less than lifetime exposures.

    Science.gov (United States)

    Geraets, Liesbeth; Nijkamp, Monique M; Ter Burg, Wouter

    2016-11-01

    Less than lifetime exposure has confronted risk assessors as to how to interpret the risks for human health in case a chronic health-based limit is exceeded. Intermittent, fluctuating and peak exposures do not match with the basis of the chronic limit values possibly leading to conservative outcomes. This paper presents guidance on how to deal with human risk assessment of less than lifetime exposure. Important steps to be considered are characterization of the human exposure situation, evaluation whether the human less than lifetime exposure scenario corresponds to a non-chronic internal exposure: toxicokinetic and toxicodynamic considerations, and, finally, re-evaluation of the risk assessment. Critical elements for these steps are the mode of action, Haber's rule, and toxicokinetics (ADME) amongst others. Previous work for the endpoints non-genotoxic carcinogenicity and developmental toxicity is included in the guidance. The guidance provides a way to consider the critical elements, without setting default factors to correct for the less than lifetime exposure in risk assessment. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Comparison of skin decontamination efficacy of commercial decontamination products following exposure to VX on human skin.

    Science.gov (United States)

    Thors, L; Koch, M; Wigenstam, E; Koch, B; Hägglund, L; Bucht, A

    2017-08-01

    The decontamination efficacy of four commercially available skin decontamination products following exposure to the nerve agent VX was evaluated in vitro utilizing a diffusion cell and dermatomed human skin. The products included were Reactive Skin Decontamination Lotion (RSDL), the Swedish decontamination powder 104 (PS104), the absorbent Fuller's Earth and the aqueous solution alldecontMED. In addition, various decontamination procedures were assessed to further investigate important mechanisms involved in the specific products, e.g. decontamination removal from skin, physical removal by sponge swabbing and activation of degradation mechanisms. The efficacy of each decontamination product was evaluated 5 or 30 min after dermal application of VX (neat or diluted to 20% in water). The RSDL-lotion was superior in reducing the penetration of VX through human skin, both when exposed as neat agent and when diluted to 20% in water. Swabbing with the RSDL-sponge during 2 min revealed decreased efficacy compared to applying the RSDL-lotion directly on the skin for 30 min. Decontamination with Fuller's Earth and alldecontMED significantly reduced the penetration of neat concentration of VX through human skin. PS104-powder was insufficient for decontamination of VX at both time-points, independently of the skin contact time of PS104. The PS104-slurry (a mixture of PS104-powder and water), slightly improved the decontamination efficacy. Comparing the time-points for initiated decontamination revealed less penetrated VX for RSDL and Fuller's Earth when decontamination was initiated after 5 min compared to 30 min post-exposure, while alldecontMED displayed similar efficacy at both time-points. Decontamination by washing with water only resulted in a significant reduction of penetrated VX when washing was performed 5 min after exposure, but not when decontamination was delayed to 30 min post-exposure of neat VX. In conclusion, early initiated decontamination with the

  7. HUMAN EXPOSURE TO THE ARTIFICIAL RADIONUCLIDES IN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Ivana Vukanac

    2012-09-01

    Full Text Available Artificial radionuclides are product of different human activities and their presence in the environment is negative side effect of civilization progress. They have been spread in the environment by events such as nuclear weapon tests, nuclear accidents and by deliberate and negligent discharge of radioactive waste from nuclear and other installation. Once released in to the nature, the artificial radionuclides start to circle in the same manner as naturally occurring ones, and finally they fall out from air and water onto the ground and build into the foodstuff and drinking water resulting in radiation doses to human beings. The short overview of presence of artificial radioactivity in human environment and its impact on human life is presented in this paper.

  8. HUMAN EXPOSURE TO THE ARTIFICIAL RADIONUCLIDES IN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Ivana Vukanac

    2012-09-01

    Full Text Available Artificial radionuclides are product of different human activities and their presence in the environment is negative side effect of civilization progress. They have been spread in the environment by events such as nuclear weapon tests, nuclear accidents and by deliberate and negligent discharge of radioactive waste from nuclear and other installation. Once released in to the nature, the artificial radionuclides start to circle in the same manner as naturally occurring ones, and finally they fall out from air and water onto the ground and build into the foodstuff and drinking water resulting in radiation doses to human beings. The short overview of presence of artificial radioactivity in human environment and its impact on human life is presented in this paper

  9. Molecular effects of 1-naphthyl-methylcarbamate and solar radiation exposures on human melanocytes.

    Science.gov (United States)

    Ferrucio, Bianca; Tiago, Manoela; Fannin, Richard D; Liu, Liwen; Gerrish, Kevin; Maria-Engler, Silvya Stuchi; Paules, Richard S; Barros, Silvia Berlanga de Moraes

    2017-02-01

    Carbaryl (1-naphthyl-methylcarbamate), a broad-spectrum insecticide, has recently been associated with the development of cutaneous melanoma in an epidemiological cohort study with U.S. farm workers also exposed to ultraviolet radiation, the main etiologic factor for skin carcinogenesis. We hypothesized that carbaryl exposure may increase deleterious effects of UV solar radiation on skin melanocytes. This study aimed to characterize human melanocytes after individual or combined exposure to carbaryl (100μM) and solar radiation (375mJ/cm 2 ). In a microarray analysis, carbaryl, but not solar radiation, induced an oxidative stress response, evidenced by the upregulation of antioxidant genes, such as Hemeoxygenase-1 (HMOX1), and downregulation of Microphtalmia-associated Transcription Factor (MITF), the main regulator of melanocytic activity; results were confirmed by qRT-PCR. Carbaryl and solar radiation induced a gene response suggestive of DNA damage and cell cycle alteration. The expression of CDKN1A, BRCA1/2 and MDM2 genes was notably more intense in the combined treatment group, in a synergistic manner. Flow cytometry assays demonstrated S-phase cell cycle arrest, reduced apoptosis levels and faster induction of cyclobutane pyrimidine dimers (CPD) lesions in carbaryl treated groups. Our data suggests that carbaryl is genotoxic to human melanocytes, especially when associated with solar radiation. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Human fetuses do not register chromosome damage inflicted by radiation exposure in lymphoid precursor cells

    International Nuclear Information System (INIS)

    Nakamura, N.; Ohtaki, K.; Kodama, Y.; Nakano, M.; Itoh, M.; Awa, A.A.; Cologne, J.B.

    2003-01-01

    Human fetuses are generally thought to be highly sensitive to radiation exposure since diagnostic, low-dose X rays (5-50 mSv) have been suggested to increase the risk of childhood leukemia by about 50%. In contrast, animal studies generally did not demonstrate a high radiosensitivity of fetuses and the underlying causes for the discrepancy are not understood. Here, we examined atomic-bomb survivors exposed in utero for translocation frequency in blood lymphocytes at 40 years of age. Contrary to our expectation of higher radiosensitivity in fetuses than in adults, the frequency did not increase with dose except for a small, but statistically significant increase (<1%) at doses below 0.1 Sv. Although an upward convex, humped dose response has been observed in other instances, the peak usually lies at doses above a few Gy, and few examples are known showing the peak response at such low doses. We interpret the results as indicating that fetal lymphoid and/or their precursor cells are sensitive to elimination through apoptosis when damaged. Our results provide a biological basis to resolve the long-standing controversy that substantial risk of childhood leukemia is implicated in human fetuses exposed to low-dose diagnostic X rays whereas animal studies composed mainly of exposures to higher doses consistently fail to confirm it

  11. An approach for assessing human exposures to chemical mixtures in the environment

    International Nuclear Information System (INIS)

    Rice, Glenn; MacDonell, Margaret; Hertzberg, Richard C.; Teuschler, Linda; Picel, Kurt; Butler, Jim; Chang, Young-Soo; Hartmann, Heidi

    2008-01-01

    Humans are exposed daily to multiple chemicals, including incidental exposures to complex chemical mixtures released into the environment and to combinations of chemicals that already co-exist in the environment because of previous releases from various sources. Exposures to chemical mixtures can occur through multiple pathways and across multiple routes. In this paper, we propose an iterative approach for assessing exposures to environmental chemical mixtures; it is similar to single-chemical approaches. Our approach encompasses two elements of the Risk Assessment Paradigm: Problem Formulation and Exposure Assessment. Multiple phases of the assessment occur in each element of the paradigm. During Problem Formulation, analysts identify and characterize the source(s) of the chemical mixture, ensure that dose-response and exposure assessment measures are concordant, and develop a preliminary evaluation of the mixture's fate. During Exposure Assessment, analysts evaluate the fate of the chemicals comprising the mixture using appropriate models and measurement data, characterize the exposure scenario, and estimate human exposure to the mixture. We also describe the utility of grouping the chemicals to be analyzed based on both physical-chemical properties and an understanding of environmental fate. In the article, we also highlight the need for understanding of changes in the mixture composition in the environment due to differential transport, differential degradation, and differential partitioning to other media. The section describes the application of the method to various chemical mixtures, highlighting issues associated with assessing exposures to chemical mixtures in the environment

  12. Negative Effects of High Glucose Exposure in Human Gonadotropin-Releasing Hormone Neurons

    Directory of Open Access Journals (Sweden)

    Annamaria Morelli

    2013-01-01

    Full Text Available Metabolic disorders are often associated with male hypogonadotropic hypogonadism, suggesting that hypothalamic defects involving GnRH neurons may impair the reproductive function. Among metabolic factors hyperglycemia has been implicated in the control of the reproductive axis at central level, both in humans and in animal models. To date, little is known about the direct effects of pathological high glucose concentrations on human GnRH neurons. In this study, we investigated the high glucose effects in the human GnRH-secreting FNC-B4 cells. Gene expression profiling by qRT-PCR, confirmed that FNC-B4 cells express GnRH and several genes relevant for GnRH neuron function (KISS1R, KISS1, sex steroid and leptin receptors, FGFR1, neuropilin 2, and semaphorins, along with glucose transporters (GLUT1, GLUT3, and GLUT4. High glucose exposure (22 mM; 40 mM significantly reduced gene and protein expression of GnRH, KISS1R, KISS1, and leptin receptor, as compared to normal glucose (5 mM. Consistent with previous studies, leptin treatment significantly induced GnRH mRNA expression at 5 mM glucose, but not in the presence of high glucose concentrations. In conclusion, our findings demonstrate a deleterious direct contribution of high glucose on human GnRH neurons, thus providing new insights into pathogenic mechanisms linking metabolic disorders to reproductive dysfunctions.

  13. Children's advertising exposure and materialistic orientations: A longitudinal study

    NARCIS (Netherlands)

    Opree, S.J.; Valkenburg, P.M.; Reijmersdal, E.A. van; Buijzen, M.A.

    2012-01-01

    As many as nine out of 10 parents worry that children's frequent exposure to advertising makes them materialistic. In this study we not only aim to investigate if children's advertising exposure indeed affects their materialism, but also how it affects their materialism (i.e., by studying the

  14. Recruitment and Retention Strategies for Environmental Exposure Studies: Lessons from the Detroit Exposure and Aerosol Research Study

    Science.gov (United States)

    The Environmental Protection Agency’s Detroit Exposure and Aerosol Research Study (DEARS) was a complex 3-year personal exposure study. The six geographically defined areas in the Detroit (Wayne County), Michigan, area used as study locations are ethnically diverse; the majority ...

  15. Environmental chemicals in human milk: a review of levels, infant exposures and health, and guidance for future research

    International Nuclear Information System (INIS)

    LaKind, Judy S.; Amina Wilkins, A.; Berlin, Cheston M.

    2004-01-01

    The aim of this review is to introduce the reader to various science and policy aspects of the topic of environmental chemicals in human milk. Although information on environmental chemicals in human milk has been available since the 1950s, it is only relatively recently that public awareness of the issue has grown. This review on environmental chemicals in human milk provides a resource summarizing what is currently known about levels and trends of environmental chemicals in human milk, potential infant exposures, and benefits of breast-feeding relative to the risks of exposures to environmental chemicals. The term 'environmental chemicals', as it pertains to human milk, refers to many classes of exogenous chemicals that may be detected in human milk. For example, pharmaceutical agents and alcohol are environmental chemicals that have been found in human milk. Other chemicals, such as heavy metals and volatile organic compounds, have also been detected in human milk. Most research on environmental chemicals in human milk has concentrated on persistent, bioaccumulative, and toxic (PBT) chemicals. In this review, a description of human milk is provided, including a brief review of endogenous substances in human milk. Determinants of levels of PBTs are discussed, as are models that have been developed to predict levels of PBTs in human milk and associated body burdens in breast-feeding infants. Methodologies for human milk sampling and analysis, and concepts for consideration in interpretation and communication of study results, as developed by the Technical Workshop on Human Milk Surveillance and Research for Environmental Chemicals in the United States are described. Studies which have compared the health risks and benefits associated with breast-feeding and formula-feeding are discussed

  16. Effects of Long-Term Dust Exposure on Human Respiratory System Health in Minqin County, China.

    Science.gov (United States)

    Wang, Jinyu; Li, Sheng; Wang, Shigong; Shang, Kezheng

    2015-01-01

    The aim of this study was to assess the effects of long-term sand dust exposure on human respiratory health. Dust events break out frequently in Minqin County, northwest China, whereas Pingliang City, northwest China, is rarely influenced by dust events. Therefore, Minqin and Pingliang were selected as sand dust exposure region and control area, respectively. The incidence of respiratory system diseases and symptoms was determined through a structured respiratory health questionnaire (ATS-DLD-78-A) and personal interviews. The subjects comprised 728 farmers (Minqin, 424; Pingliang, 304) aged 40 years or older, who had nondocumented occupational history to industrial dust exposure. Prevalences (odds ratio [OR], 95% confidence interval [CI]) of chronic rhinitis, chronic bronchitis, and chronic cough increased 9.6% (3.141, 1.776-5.555), 7.5% (2.468, 1.421-4.286), and 10.2% (1.787, 1.246-2.563) in Minqin comparison with Pingliang, respectively, and the differences were significant (p <.01).

  17. Biomonitoring of Human Exposure to Prestige Oil: Effects on DNA and Endocrine Parameters

    Directory of Open Access Journals (Sweden)

    Beatriz Pérez-Cadahía

    2008-01-01

    Full Text Available Since 1960, about 400 tankers spilled more than 377765 tons of oil, with the Prestige accident (Galician coast, NW Spain, November 2002 the most recent. Taking into account the consistent large number of individuals exposed to oil that exists all over the world, it seems surprising the absence in the literature of studies focused on the chronic effects of this exposure on human health. In this work we evaluated the level of DNA damage by means of comet assay, and the potential endocrine alterations (prolactin and cortisol caused by Prestige oil exposure in a population of 180 individuals, classified in 3 groups according to the tasks performed, and 60 controls. Heavy metals in blood were determined as exposure biomarkers, obtaining significant increases of aluminum, nickel and lead in the exposed groups as compared to controls. Higher levels of genetic damage and endocrine alterations were also observed in the exposed population. DNA damage levels were influenced by age, sex, and the use of protective clothes, and prolactin concentrations by the last two factors. Surprisingly, the use of mask did not seem to protect individuals from genetic or endocrine alterations. Moreover, polymorphisms in genes encoding for the main enzymes involved in the metabolism of oil components were analyzed as susceptibility biomarkers. CYP1A1-3’UTR and EPHX1 codons 113 and 139 variant alleles were related to higher damage levels, while lower DNA damage was observed in GSTM1 and GSTT1 null individuals.

  18. The role of dietary habits in human internal exposure

    International Nuclear Information System (INIS)

    Travnikova, I.G.; Balonov, M.I.; Bruck, G.J.; Shutov, V.N.

    2002-01-01

    The diversity of the dietary habits of the inhabitants living in the areas contaminated with long-lived radionuclides is an important factor for finding out the ways and specific features of internal dose formation of the population. The diet and structure of food consumption of different contingents of the population in several regions subjected to the radioactive accidents were studied. Using the specially developed questionnaire, we surveyed in Russia over 3000 inhabitants of the Bryansk region, and found out their food rations before the Chernobyl accident and during different time periods after it. In the Urals, we surveyed 102 inhabitants of the village Muslyumovo located on the bank of the Techa river that was contaminated as a result of releases of products of processing nuclear fuel and also more than 136 people residing in the area of the East Ural Radioactive Trace. In the North of the European part of Russia we investigated 310 local inhabitants including 114 reindeer herders. In Kazakhstan, we polled over 114 residents of the Semipalatinsk nuclear test site area, including 23 herdsmen and members of their families. The dietary habits of all investigated groups of the population strongly differ both due to climatic conditions and national and confessional traditions. Besides that, they are strongly influenced by the sources of the contamination of local food products that also differ both by radionuclide composition and by the time period elapsed since contamination of the considered areas. On the basis of the obtained results, we calculated the internal doses for the population of mentioned regions, which are in good coincidence with the data of direct measurements of radionuclides content in human body. We have determined, which products have the leading role in internal dose formation during different time periods after depositions

  19. A Review of Human Health and Ecological Risks due to CO2 Exposure

    Science.gov (United States)

    Hepple, R. P.; Benson, S. M.

    2001-05-01

    Nyos in Cameroon, Mammoth Mountain in California, Dieng Volcanic Complex in Java, Indonesia, and industrial accidents with CO2 fire suppression systems teach that slow leakage rates and effective dilution must be proven to ensure human and environmental safety. Monitoring CO2 levels in occupational settings is done with reliable IR sensors. Remote sensing of low levels of CO2 over long distances cannot be done easily yet, although LIDAR, an airborne laser technique under development, may have good potential. The environmental impacts of elevated CO2 levels on vegetation are being investigated now in free-air CO2 enrichment studies. In general, persistent elevated CO2 levels cause a change in species composition, favoring C3 plants over C4 or CAM. The ecological effects of catastrophic releases are severe but depend upon (a) release rate and amount, (b) surface topography and rate of atmospheric mixing (c) exposure concentrations and duration, (d) the respiratory mechanism of the form of life under discussion, (e) its tolerance for oxygen deprivation, and (f) its ability to maintain homeostatic pH levels. Suppression of root respiration due to elevated soil-gas CO2 concentrations and acidifiction of the root zone are known mechanisms of tree-kill. Soil-gas CO2 in the tree-kill areas at Mammoth Mountain exceeded 20-30% at 15 cm depth. Surface masses of concentrated CO2 probably smother the canopy through oxygen deprivation, but the precise mechanism is not known. Lake Nyos and Mammoth Mountain reveal that catastrophic releases can result in complete dead zones.

  20. Temperature elevation in the eye of anatomically based human head models for plane-wave exposures

    International Nuclear Information System (INIS)

    Hirata, A; Watanabe, S; Fujiwara, O; Kojima, M; Sasaki, K; Shiozawa, T

    2007-01-01

    This study investigated the temperature elevation in the eye of anatomically based human head models for plane-wave exposures. The finite-difference time-domain method is used for analyzing electromagnetic absorption and temperature elevation. The eyes in the anatomic models have average dimensions and weight. Computational results show that the ratio of maximum temperature in the lens to the eye-average SAR (named 'heating factor for the lens') is almost uniform (0.112-0.147 deg. C kg W -1 ) in the frequency region below 3 GHz. Above 3 GHz, this ratio increases gradually with an increase of frequency, which is attributed to the penetration depth of an electromagnetic wave. Particular attention is paid to the difference in the heating factor for the lens between this study and earlier works. Considering causes clarified in this study, compensated heating factors in all these studies are found to be in good agreement

  1. Personal exposure to particulate PAHs and anthraquinone and oxidative DNA damages in humans.

    Science.gov (United States)

    Wei, Yongjie; Han, In-Kyu; Hu, Min; Shao, Min; Zhang, Junfeng Jim; Tang, Xiaoyan

    2010-11-01

    Recent studies suggest that DNA oxidative damage be related to the chemical constituents of ambient particles. The purpose of this study was to examine whether particulate polycyclic aromatic hydrocarbons (PAHs) and quinone-structure chemicals increase body burden of oxidative stress in human exposed to heavy traffic volume. We recruited two nonsmoking security guards who worked at a university campus gate near a heavily trafficked road. Each subject wore a personal air sampler for 24h per day to estimate exposures to 24 PAHs and anthraquinone (AnQ) in PM(2.5). Daily pre- and post-work shift spot urines were collected for 29d from each subject. Urine samples were analyzed for 8-hydroxy-2'-deoxyguanosine (8-OHdG). Additionally, using 19 organic tracers other than 24 PAHs and AnQ, a receptor source apportionment model of chemical mass balance was applied to determine the contributions of sources on the PM: gasoline vehicle, diesel vehicle, coal burning, vegetable debris, cooking, natural gas and biomass burning. The relationship among urinary 8-OHdG, individual PAH, and AnQ was demonstrated as follows: the average urinary concentration of 8-OHdG was increased more than three times after 8-h work-shift than those before the work shift. All the 24 PAH and AnQ levels were positively and significantly associated with the post-work urinary 8-OHdG. The results from source apportionment suggest vehicular emission to be the dominant source of personal exposure to PM(2.5). Our finding indicates that personal air exposures to 24 individual PAHs and AnQ originating from traffic emissions are important in increasing oxidative burdens in human body. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Proposed retention model for human inhalation exposure to 241AmO2

    International Nuclear Information System (INIS)

    Mewhinney, J.A.; Griffith, W.C.; Muggenburg, B.A.

    1980-01-01

    A dosimetry model based on a four-year study in Beagle dogs was developed to predict patterns of absorbed radiation doses for people exposed by inhalation to 241 AmO 2 . Following a single inhalation exposure to one of three sizes of monodisperse or a polydisperse aerosol of 241 AmO 2 , pairs of dogs were sacrificed at 8, 32, 64 and 256 days, and 2 and 4 years. For about 80% of the initial lung burden, the retention halftimes were 11, 18, 26 and 27 days for the 0.75, 1.5 and 3.0 μm aerodynamic diameter and the 1.8 μm activity median aerodynamic diameter aerosols, respectively. For the remaining 20% of the initial lung burden, the retention halftimes were between 200 to 300 days with no apparent particle size influence. Additional 241 Am metabolic studies reported in the literature using inhalation exposure or injection of the citrate complex were synthesized in the model as were eleven reported cases of human inhalation exposure. This model is compared to the ICRP II and TGLD lung models, both developed by analogy to Pu metabolism. The proposed model differs from these latter models in two important areas: (a) lung retention of 241 AmO 2 could not be adapted to the classifications used in these models, and (b) the fractional translocation from lung to other organs is 2 to 8 times larger. These factors considerably alter the predicted radiation dose distribution among organs and lead to the conclusion that derived radiation protection standards for 241 AmO 2 inhalation exposure should be modified. (author)

  3. Carcinogenesis--a synopsis of human experience with external exposure in medicine

    International Nuclear Information System (INIS)

    Boice, J.D. Jr.

    1988-01-01

    Studies in the 1980s of medically irradiated populations have increased our knowledge of radiation carcinogenesis. (1) Investigations of prenatal x-ray exposures, especially in twins, provide evidence that very low doses of ionizing radiation may cause cancer in humans. (2) Fractionated doses appear as effective as single exposures of the same total dose in causing breast cancer, but seem less effective for lung cancer. (3) Excess breast cancers can occur among women exposed under age 10, indicating that the immature breast is susceptible to the carcinogenic action of radiation. (4) Moderate doses on the order of 1 Gy to the brains of children can cause tumors later in life; moderately high doses to the skin can cause cancer when followed by frequent exposure to ultraviolet light. (5) Radiotherapy for cervical cancer can increase the rate of subsequent leukemia with the best fitting dose-response functions including a negative exponential term to account for cell-killing. (6) Low-dose exposures of about 10 cGy may increase the risk of thyroid cancer. (7) Second cancers following radiotherapy for a variety of cancers occur primarily among long-term survivors. (8) Radiotherapy may not significantly increase the risk of leukemia following childhood cancer, whereas chemotherapy with alkylating agents is a major risk factor. (9) Bone cancer occurs after high-dose radiotherapy for childhood cancer, but children with retinoblastoma are not more susceptible to radiation-induced disease than children with other malignancies. (10) High-dose external beam therapy can cause thyroid cancer. (11) Studies of cervical cancer patients indicate that the risk of radiation-induced second malignancies follows a time-response model consistent with a constant multiplication of the underlying background incidence. 83 references

  4. Human Infection with MERS coronavirus after exposure to infected camels, Saudi Arabia, 2013

    NARCIS (Netherlands)

    Memish, Ziad A.; Cotten, Matthew; Meyer, Benjamin; Watson, Simon J.; Alsahafi, Abdullah J.; Al Rabeeah, Abdullah A.; Corman, Victor Max; Sieberg, Andrea; Makhdoom, Hatem Q.; Assiri, Abdullah; Al Masri, Malaki; Aldabbagh, Souhaib; Bosch, Berend Jan|info:eu-repo/dai/nl/273306049; Beer, Martin; Müller, Marcel A.; Kellam, Paul; Drosten, Christian

    2014-01-01

    We investigated a case of human infection with Middle East respiratory syndrome coronavirus (MERS-CoV) after exposure to infected camels. Analysis of the whole human-derived virus and 15% of the camel-derived virus sequence yielded nucleotide polymorphism signatures suggestive of cross-species

  5. Influence of occupational exposure to pesticides on lymphocytes responses to environment and UV. Report from the EC Project ERBIC 15CT 960300 'Pesticide Effects on Humans'

    International Nuclear Information System (INIS)

    2000-01-01

    The report presented studies of the genotoxic influence of occupational exposure to pesticides on human lymphocytes. The susceptibility of the cells to UV-C radiation and repair capacities of DNA damages were examined

  6. A COMPARATIVE STUDY OF WHOLE-BODY VIBRATION EXPOSURE IN TRAIN AND CAR PASSENGERS: A CASE STUDY IN MALAYSIA

    Directory of Open Access Journals (Sweden)

    M.M. Rahman

    2011-12-01

    Full Text Available Trains and cars are the most important modes of transportation throughout the world. In highly developed countries, trains have become essential for human use as the most well-known form of public transportation, whereas the car plays a significant role in prompt human travel from one place to another. The high magnitude of vibration caused by trains and cars may cause health problems in humans, especially low back pain. The aim of this study was to evaluate and validate the values of daily exposure to vibration A(8 and the vibration dose value (VDV in passengers travelling by train and car and to assess the effects produced by this exposure on the human body. Moreover, this study introduces a newly developed whole-body vibration measurement instrumentation system. One train travelling from the east coast to the south of Malaysia was chosen to conduct the study. Whole-body vibration exposure was measured over 8 hours, which is equal to the duration of normal occupational exposure. One car was chosen randomly and whole-body vibration exposure was measured for 5 min and 10 min. All the data were computed using an IEPE(ICPTM accelerometer sensor connected to a DT9837 device which is capable of effectively measuring and analysing vibration. The vibration results were displayed on a personal computer using a custom graphical user interface (GUI. Matlab software was used to interpret the data. From the results, the whole-body vibration exposure level could be determined. It can be concluded that the whole-body vibration absorbed by the human body is enhanced when the magnitude of the vibration exposure experienced by the passengers increased. This was shown by the increased values of daily exposure to vibration A(8 and VDV calculated in the study.

  7. Limiting criteria for human exposure to low humidity indoors

    DEFF Research Database (Denmark)

    Wyon, David; Fang, Lei; Meyer, H.

    2002-01-01

    Thirty subjects (17 female) were exposed for 5 hours to clean air at 5%, 15%, 25% and 35% RH at 22 deg.C. Another 30 subjects (15 female) were similarly exposed to air polluted by carpet and linoleum at 18, 22 and 26 deg.C with humidity 2.4 g/kg dry air (=15% RH at 22 deg.C), and at 22 deg.C, 35......% RH. The subjects performed simulated office work throughout each exposure. Building Related Symptom (BRS) intensity was reported on visual-analogue scales. Tests of eye, nose and skin function were applied. In these short exposures subjective discomfort, though significantly increased by low humidity......, was very moderate even at 5% RH. However, tear film quality as indicated by the Mucous Ferning Test deteriorated significantly at RH22 deg.C, significantly more rapid blink rates were observed at 5% than at 35% RH, and skin became significantly more dry at 15% than at 35% RH....

  8. Environmental and human exposure as a result of radioactive discharges

    International Nuclear Information System (INIS)

    2010-02-01

    Nuclear accidents can lead to the discharge of radioactive particulates, gases, and liquid effluents into the environment. Effluents are characterized by their composition, duration and by other characteristics which can influence the dispersion of radioactivity in the environment. Populations can be exposed directly or through the contamination of the terrestrial and aquatic environments. Therefore, it is necessary to take into consideration both the environmental contamination pathways and the human contamination pathways through the environment. This document summarizes these different pathways: contamination by atmospheric discharge (surface contamination, surface waters, terrestrial fauna and flora); contamination by liquid discharge; spreading of contaminated areas; human contamination pathways (external irradiation, internal contamination, skin contamination). (J.S.)

  9. Exposure, uptake, distribution and toxicity of nanomaterials in humans.

    Science.gov (United States)

    Holgate, Stephen T

    2010-02-01

    The last decade has witnessed an unprecedented explosion in nanotechnology to take advantage of the unique physicochemical properties that emerge at the nanoscale including quantum effects. However, the excitement generated by new applications of nanotechnology in products has not been matched by a parallel appreciation or understanding of their potential toxic effects in humans and the wider ecology. This review draws some parallels to what we already know about the toxicity of particles in the workplace and in association with air pollution, and then discusses what is known about the toxicology of nanomaterials in mammals including humans. The review identifies substantial gaps in knowledge and makes some recommendations for future research.

  10. Sun Exposure and Its Effects on Human Health: Mechanisms through Which Sun Exposure Could Reduce the Risk of Developing Obesity and Cardiometabolic Dysfunction

    Science.gov (United States)

    Fleury, Naomi; Geldenhuys, Sian; Gorman, Shelley

    2016-01-01

    Obesity is a significant burden on global healthcare due to its high prevalence and associations with chronic health conditions. In our animal studies, ongoing exposure to low dose ultraviolet radiation (UVR, found in sunlight) reduced weight gain and the development of signs of cardiometabolic dysfunction in mice fed a high fat diet. These observations suggest that regular exposure to safe levels of sunlight could be an effective means of reducing the burden of obesity. However, there is limited knowledge around the nature of associations between sun exposure and the development of obesity and cardiometabolic dysfunction, and we do not know if sun exposure (independent of outdoor activity) affects the metabolic processes that determine obesity in humans. In addition, excessive sun exposure has strong associations with a number of negative health consequences such as skin cancer. This means it is very important to “get the balance right” to ensure that we receive benefits without increasing harm. In this review, we detail the evidence around the cardiometabolic protective effects of UVR and suggest mechanistic pathways through which UVR could be beneficial. PMID:27727191

  11. Human exposure to airborne fungi from genera used as biocontrol agents in plant production.

    Science.gov (United States)

    Madsen, Anne Mette; Hansen, Vinni Mona; Meyling, Nicolai Vitt; Eilenberg, Jørgen

    2007-01-01

    The fungi Trichoderma harzianum, T. polysporum, T. viride, Paeciliomyces fumosoroseus, P. lilacinus, Verticillium/lecanicillium lecanii, Ulocladium oudemansii, U. atrum and Beauveria bassiana are used or considered to be used for biocontrol of pests and plant diseases. Human exposure to these fungi in environments where they may naturally occur or are used as biocontrol agents has not been directly investigated to date. This review aims to provide an overview of the current knowledge of human exposure to fungi from the relevant genera. The subject of fungal taxonomy due to the rapid development of this issue is also discussed. B. bassiana, V. lecanii, T. harzianum, T. polysporum, P. lilacinus and U. oudemansii were infrequently present in the air and thus people in general seem to be seldom exposed to these fungi. However, when V. lecanii was present, high concentrations were measured. Fungi from the genera Trichoderma, Paecilomyces and Ulocladium were rarely identified to the species level and sometimes high concentrations were reported. T. viride and U. atrum were detected frequently in different environments and sometimes with a high frequency of presence in samples. Thus, people seem to be frequently exposed to these fungi. Sequence data have led to recent revisions of fungal taxonomy, and in future studies it is important to specify the taxonomy used for identification, thus making comparisons possible.

  12. Assessment of human exposure to pesticides by hair analysis: The case of vegetable-producing areas in Burkina Faso.

    Science.gov (United States)

    Lehmann, Edouard; Oltramare, Christelle; Nfon Dibié, Jean-Jacques; Konaté, Yacouba; de Alencastro, Luiz Felippe

    2018-02-01

    The present work assesses human exposure to pesticides in vegetable-producing areas in Burkina Faso, using hair as an indicator. The study design includes a comparison between operators who are occupationally exposed while working in the fields and a reference population (i.e. not occupationally exposed) to evaluate both occupational and indirect exposures. Hair samples from volunteers (n=101) were positive for 17 pesticides (38 analyzed). Acetamiprid, desethylatrazine, carbofuran, and deltamethrin were detected for the first time in field samples. With a maximum of 9 residues per sample, pesticide exposure was ubiquitous in both populations. Contamination by acetamiprid, cypermethrin, and lambda-cyhalothrin (used in vegetable production) prevailed in operator samples. For other pesticides, such as imidacloprid and deltamethrin, no significant difference was found. This indicates a potentially large environmental exposure (dietary intake or atmospheric contamination) or the prevalence of other contamination sources. The present findings are concerning, as detected levels are globally higher than those previously reported, and indicate exposure to endocrine disrupting chemicals and probable carcinogens. Hair was found to be a suitable matrix for biomonitoring human exposure to pesticides and assessing dominant factors (i.e. sex, age, and protective equipment) in subgroups, as well as identifying geographical contamination patterns. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. 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

  14. Human exposure to high natural background radiation: what can it teach us about radiation risks?

    International Nuclear Information System (INIS)

    Hendry, Jolyon H; Sohrabi, Mehdi; Burkart, Werner; Simon, Steven L; Wojcik, Andrzej; Cardis, Elisabeth; Laurier, Dominique; Tirmarche, Margot; Hayata, Isamu

    2009-01-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of 222 Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case-control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case-control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors.

  15. Human exposure to high natural background radiation: what can it teach us about radiation risks?

    Energy Technology Data Exchange (ETDEWEB)

    Hendry, Jolyon H; Sohrabi, Mehdi; Burkart, Werner [Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Vienna (Austria); Simon, Steven L [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD (United States); Wojcik, Andrzej [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Cardis, Elisabeth [Centre for Research in Environmental Epidemiology (CREAL), Municipal Institute of Medical Research (IMIM-Hospital del Mar) and CIBER Epidemiologia y Salud Publica - CIBERESP, Barcelona (Spain); Laurier, Dominique; Tirmarche, Margot [Radiobiology and Epidemiology Department, Radiological and Human Health Division, Institute for Radiological Protection and Nuclear Safety, Fontenay-aux-Roses (France); Hayata, Isamu [National Institute of Radiological Sciences, Chiba (Japan)], E-mail: jhendry2002uk@yahoo.com

    2009-06-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of {sup 222}Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case-control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case-control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors.

  16. Human exposure to high natural background radiation: what can it teach us about radiation risks?

    Science.gov (United States)

    Hendry, Jolyon H; Simon, Steven L; Wojcik, Andrzej; Sohrabi, Mehdi; Burkart, Werner; Cardis, Elisabeth; Laurier, Dominique; Tirmarche, Margot; Hayata, Isamu

    2014-01-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of 222Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case–control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case–control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors. PMID:19454802

  17. High Throughput Heuristics for Prioritizing Human Exposure to Environmental Chemicals

    Science.gov (United States)

    The risk posed to human health by any of the thousands of untested anthropogenic chemicals in our environment is a function of both the potential hazard presented by the chemical, and the possibility of being exposed. Without the capacity to make quantitative, albeit uncertain, f...

  18. Factors affecting outdoor exposure in winter: population-based study

    Science.gov (United States)

    Mäkinen, Tiina M.; Raatikka, Veli-Pekka; Rytkönen, Mika; Jokelainen, Jari; Rintamäki, Hannu; Ruuhela, Reija; Näyhä, Simo; Hassi, Juhani

    2006-09-01

    The extent of outdoor exposure during winter and factors affecting it were examined in a cross-sectional population study in Finland. Men and women aged 25-74 years from the National FINRISK 2002 sub-study ( n=6,591) were queried about their average weekly occupational, leisure-time and total cold exposure during the past winter. The effects of gender, age, area of residence, occupation, ambient temperature, self-rated health, physical activity and education on cold exposure were analysed. The self-reported median total cold exposure time was 7 h/week (8 h men, 6 h women),employed in agriculture, forestry and industry/mining/construction or related occupations, being less educated and being aged 55-64 years. Factors associated with increased leisure-time cold exposure among men were: employment in industry/mining/construction or related occupations, being a pensioner or unemployed,