WorldWideScience

Sample records for toxic exposure personnel

  1. Personnel exposures in industrial radiography

    International Nuclear Information System (INIS)

    Shenoy, K.S.; Patel, P.H.

    1979-01-01

    The manifold increase in production, and ease of availability of radioisotopes in India have been responsible for a tremendous increase in use of radioisotopes in industrial radiography during past fifteen years. Among various applications of radioisotopes the industrial radiography involves a large potential risk of occupational radiation exposures. The dose records of past fifteen years in respect of all radiation workers maintained by the Personnel Monitoring Group of Division of Radiological Protection of the Bhabha Atomic Research Centre, Bombay, have been analysed. Analysis of excessive exposure (exceeding 400 mrem/fortnight) reveals that this figure is increasing at an alarming rate among the radiation workers of this category. In spite of various regulatory controls the dose per person per week has remained higher as compared to the same in other categories. This combined with the increase in number of radiation workers every year would soon contribute significantly to the per capita dose for radiation workers. Use of adequately shielded fool-proof remote control equipment and training of all personnel in safe handling of radiation sources seem to be the only solution to arrest the rate of increase in personnel exposures of this category. (auth.)

  2. Occupational exposure of nuclear medicine personnel

    International Nuclear Information System (INIS)

    Roessler, M.

    1982-01-01

    The results are given of measurements of the radiation burden of personnel in departments of nuclear medicine in the years 1979 to 1981 using film dosemeters and ring thermoluminescence dosemeters evaluated by the national personnel dosemeter service. The relations are examined of the exposure of hands and the preparation of radiopharmaceuticals and especially their use for examinations. Certain organizational measures are indicated for reducina radiation burden in a laboratory for the preparation of radiopharmaceuticals. The results of measurements and evaluations of radiation burden of personnel of nuclear medicine departments are confronted with conclusions published in the literature. (author)

  3. Preschool Personnel Exposure to Occupational Noise

    Directory of Open Access Journals (Sweden)

    Kaļužnaja Darja

    2016-10-01

    Full Text Available Increased noise, which is also below the occupational exposure values and is “hearing safe” noise, affects the exposed person’s health as a non-specific stressor. Increased noise level also creates an environment for additional vocal apparatus load. The objective of this study was to determine preschool personnel occupational noise and its relationship with subjective health complaints. Data were obtained with survey assistance through subjective answers of respondents about health complaints and noise exposure among Rīga preschool personnel. Objective noise measurements were made to assess real noise levels in the preschool environment. Data from 155 respondents and objective measurements of 37 preschool classrooms were obtained. The results showed that the average 8-h noise exposure among Rīga preschool educational institutions was 70 dB(A, which did not exceed the Latvian work environment noise limits, but exceeded the 35–40 dB(A noise limit in the educational environment guidelines recommended by the WHO. The survey results showed that loud noise is one of the most important workplace environmental factors (~70% of respondents feel a necessity to increase voice because of noise. A constant feeling of fatigue, headache, irritable feeling, and a desire to isolate oneself from others more often occurred in respondents exposed to increased noise, compared with those who noted that they were not exposed to increased noise. In general, loud noise was associated with increased subjective health complaints in preschool education institution personnel.

  4. Asbestos exposure of building maintenance personnel.

    Science.gov (United States)

    Mlynarek, S; Corn, M; Blake, C

    1996-06-01

    The exposures of building maintenance personnel and occupants to airborne asbestos fibers, and the effects of operations and maintenance programs on those exposures, continue to be an important public health issue. The subject of this investigation was a large metropolitan county with numerous public buildings which routinely conducted air sampling for asbestos. A total of 302 personal air samples in nine task categories collected during maintenance worker activities in proximity to asbestos-containing materials were analyzed; 102 environmental air samples in four task categories were also analyzed. The arithmetic means of the 8-hr time weighted average exposures for personal sampling for each task category were all below the Occupational Safety and Health Administration permissible exposure level of 0.1 fibers (f)/cc > 5 microm. The highest mean 8-hr time weighted average exposure was 0.030 f/cc > 5 microm for ceiling tile replacement. The maximum asbestos concentration during sample collection for environmental samples was 0.027 f/cc > 5 microm. All asbestos-related maintenance work was done within the framework of an Operations and Maintenance Program (OMP) which utilized both personal protective equipment and controls against fiber release/dispersion. Results are presented in association with specific OMP procedures or controls. These results support the effectiveness of using Operations and Maintenance Programs to manage asbestos in buildings without incurring unacceptable risk to maintenance workers performing maintenance tasks.

  5. Personnel and population exposure regulation questions

    International Nuclear Information System (INIS)

    Nosovskij, A.V.

    2000-01-01

    ICRP Recommendations-1990, Notice 60 was used as a basis for new NRBU-97 norms in Ukraine and also for Russian NRB-96 and reviewed NRB-99. These recommendations caused negative treatment among rather authoritative organizations and individual scientists of France, USA, Russia and other countries. Till 1988, norms NRB-76/87 were operated in Ukraine. ICRP Recommendations-1976, Notice 26 was used under their development, and dosage limits included into them surely provided radiation protection for Nuclear Power Units personnel and population during long-term period. But some leaders being affected by Chernobyl syndrome and radio phobia put strong pressure upon ICRP that resulted in Notice 60 appearance where dosage limits for personnel and population were sufficiently understated without any scientific ground. According to literary sources survey, it is shown that usage of dose-effect non threshold linear dependence concept essentially exaggerates the real danger. According to the concept, principles of regulation the exposure standards are suggested, which considered to be actual as large-scale works on dismantling the reactors and ChNPP Units equipment are expected soon on the phase of their decommissioning and also the conducting of works on Unit 'Shelter' transformation into ecologically safe system

  6. Patient and personnel exposure during extracorporeal lithotripsy

    International Nuclear Information System (INIS)

    Glaze, S.; LeBlanc, A.D.; Bushong, S.C.; Griffith, D.P.

    1987-01-01

    Extracorporeal shock wave lithotripsy (ESWL) has provided a nonsurgical approach to treatment of renal stones. The Dornier lithotripter uses dual image intensified x-ray systems to center the stone before treatment. Three imaging modes are offered: a fluoroscopic mode and two video spot filming modes. The average entrance exposure to the stone side of the typical patient at our facility is 2.6 X 10(-3) C kg-1 (10 R) [range: 0.5-7.7 X 10(-3) C kg-1 (2-30 R)] which is comparable and often much less than that reported for percutaneous lithotripsy. Recommendations are made for minimizing patient exposure. Scattered radiation levels in the lithotripter room are presented. We have determined that Pb protective apparel is not required during this procedure provided x-ray operation is temporarily halted should personnel be required to lean directly over the tub to attend to the patient. If the walls of the ESWL room are greater than 1.83 m (6 feet) from the tub, shielding in addition to conventional construction is not required

  7. Patient and personnel exposure during extracorporeal lithotripsy

    Energy Technology Data Exchange (ETDEWEB)

    Glaze, S.; LeBlanc, A.D.; Bushong, S.C.; Griffith, D.P.

    1987-12-01

    Extracorporeal shock wave lithotripsy (ESWL) has provided a nonsurgical approach to treatment of renal stones. The Dornier lithotripter uses dual image intensified x-ray systems to center the stone before treatment. Three imaging modes are offered: a fluoroscopic mode and two video spot filming modes. The average entrance exposure to the stone side of the typical patient at our facility is 2.6 X 10(-3) C kg-1 (10 R) (range: 0.5-7.7 X 10(-3) C kg-1 (2-30 R)) which is comparable and often much less than that reported for percutaneous lithotripsy. Recommendations are made for minimizing patient exposure. Scattered radiation levels in the lithotripter room are presented. We have determined that Pb protective apparel is not required during this procedure provided x-ray operation is temporarily halted should personnel be required to lean directly over the tub to attend to the patient. If the walls of the ESWL room are greater than 1.83 m (6 feet) from the tub, shielding in addition to conventional construction is not required.

  8. Oral Chromium Exposure and Toxicity

    Science.gov (United States)

    Sun, Hong; Brocato, Jason

    2015-01-01

    Hexavalent chromium [Cr(VI)] is a known carcinogen when inhaled. However, inhalational exposure to Cr(VI) affects only a small portion of the population, mainly by occupational exposures. In contrast, oral exposure to Cr(VI) is widespread and affects many people throughout the globe. In 2008, the National Toxicology Program (NTP) released a 2-year study demonstrating that ingested Cr(VI) was carcinogenic in rats and mice. The effects of Cr(VI) oral exposure is mitigated by reduction in the gut, however a portion evades the reductive detoxification and reaches target tissues. Once Cr(VI) enters the cell, it ultimately gets reduced to Cr(III), which mediates its toxicity via induction of oxidative stress during the reduction while Cr intermediates react with protein and DNA. Cr(III) can form adducts with DNA that may lead to mutations. This review will discuss the potential adverse effects of oral exposure to Cr(VI) by presenting up-to-date human and animal studies, examining the underlying mechanisms that mediate Cr(VI) toxicity, as well as highlighting opportunities for future research. PMID:26231506

  9. Radiation exposure of nursing personnel to brachytherapy patients

    International Nuclear Information System (INIS)

    Cobb, P.D.; Kase, K.R.; Bjaerngard, B.E.

    1978-01-01

    The radiation exposure of nursing personnel to brachytherapy patients has been analyzed from data collected during the years 1973-1976, at four different hospitals. The average annual dose per exposed nurse ranged between 25 and 150 mrem. The radiation exposure per nurse was found to be proportional to the total potential exposure and was uncorrelated with the size of the nursing staff. (author)

  10. Evaluating chemical and other agent exposures for reproductive and developmental toxicity

    National Research Council Canada - National Science Library

    Subcommittee on Reproductive and Developmental Toxicity, Committee on Toxicology, Board on Environmental Studies and Toxicology, National Research Council

    2001-01-01

    .... As part of its efforts to reduce or eliminate exposure of Naval personnel and their families to reproductive and developmental toxicants, the Navy requested that the National Research Council (NRC...

  11. A Review of Mercury Exposure and Health of Dental Personnel

    Directory of Open Access Journals (Sweden)

    Natasha Nagpal

    2017-03-01

    Full Text Available Considerable effort has been made to address the issue of occupational health and environmental exposure to mercury. This review reports on the current literature of mercury exposure and health impacts on dental personnel. Citations were searched using four comprehensive electronic databases for articles published between 2002 and 2015. All original articles that evaluated an association between the use of dental amalgam and occupational mercury exposure in dental personnel were included. Fifteen publications from nine different countries met the selection criteria. The design and quality of the studies showed significant variation, particularly in the choice of biomarkers as an indicator of mercury exposure. In several countries, dental personnel had higher mercury levels in biological fluids and tissues than in control groups; some work practices increased mercury exposure but the exposure levels remained below recommended guidelines. Dental personnel reported more health conditions, often involving the central nervous system, than the control groups. Clinical symptoms reported by dental professionals may be associated with low-level, long-term exposure to occupational mercury, but may also be due to the effects of aging, occupational overuse, and stress. It is important that dental personnel, researchers, and educators continue to encourage and monitor good work practices by dental professionals.

  12. A relational database for personnel radiation exposure management

    International Nuclear Information System (INIS)

    David, W.; Miller, P.D.

    1993-01-01

    In-house utility personnel developed a relational data base for personnel radiation exposure management computer system during a 2 1/2 year period. The (PREM) Personnel Radiation Exposure Management System was designed to meet current Nuclear Regulatory Commission (NRC) requirements related to radiological access control, Radiation Work Permits (RWP) management, automated personnel dosimetry reporting, ALARA planning and repetitive job history dose archiving. The system has been operational for the past 18 months which includes a full refueling outage at Clinton Power Station. The Radiation Protection Department designed PREM to establish a software platform for implementing future revisions to 10CFR20 in 1993. Workers acceptance of the system has been excellent. Regulatory officials have given the system high marks as a radiological tool because of the system's ability to track the entire job from start to finish

  13. Personnel radiation exposure in HTGR plants

    International Nuclear Information System (INIS)

    Su, S.; Engholm, B.A.

    1981-01-01

    Occupational radiation exposures in high-temperature gas-cooled reactor (HTGR) plants were assessed. The expected rate of dose accumulations for a large HTGR steam cycle unit is 0.07 man-rem/MW(e)y, while the design basis is 0.17 man-rem/MW(e)y. The comparable figure for actual light water reactor experience is 1.3 man-rem/MW(e)y. The favorable HTGR occupational exposure is supported by results from the Peach Bottom Unit No. 1 HTGR and Fort St. Vrain HTGR plants and by operating experience at British gas-cooled reactor stations

  14. 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...

  15. Personnel exposure estimates associated with nuclear fuel reprocessing waste

    International Nuclear Information System (INIS)

    Boone, F.W.; Rogers, B.W.

    1983-08-01

    The operation design of the Barnwell Nuclear Fuel Plant (BNFP) calls for shipment of its wastes to either a low-level waste disposal site or to a Federal repository. This study analyzes the probable radiation dose accrued to the personnel involved in handling waste packages from all identified waste streams of the BNFP from generation to reception at destination and including transportation. The shielding characteristics of the transport packages were derived by assuming packaging in existing or prototyped casks. Possible combinations of waste forms and packages for which the projected dose exceeded DOT or NRC regulations for transport of radioactive materials were rejected. Legal weight truck and legal weight rail transport modes were assumed. Potential ways for reducing overall personnel exposure are considered, concentrating on the particular streams with the largest dose contributions. The personnel exposure estimates were determined using a computer program specifically designed for this purpose. This program is described in Appendix A. 9 references, 3 figures, 19 tables

  16. Computer code for calculating personnel doses due to tritium exposures

    International Nuclear Information System (INIS)

    Graham, C.L.; Parlagreco, J.R.

    1977-01-01

    This report describes a computer code written in LLL modified Fortran IV that can be used on a CDC 7600 for calculating personnel doses due to internal exposures to tritium. The code is capable of handling various exposure situations and is also capable of detecting a large variety of data input errors that would lead to errors in the dose assessment. The critical organ is the body water

  17. Personnel exposure: The last mSv (mrem)

    International Nuclear Information System (INIS)

    Mower, H.W.

    1996-01-01

    This paper very briefly presents the problems in determining personnel dose exposure history. Two scenarios are described: (1) a new employee, and (2) an employee who works for more than one employer. Several possible solutions are examined and determined to be unsuitable. It is recommended that the Conference of Radiation Control Program Directors evaluate this problem and provide suitable recommendations

  18. Development of personnel exposure management system with personal computer

    International Nuclear Information System (INIS)

    Yamato, Ichiro; Yamamoto, Toshiki

    1992-01-01

    In nuclear power plants, large scale personnel exposure management systems have been developed and established by utilities. Though being common in the base, the implementations are specific by plants. Contractors must control their workers' exposures by their own methods and systems. To comply with the utilities' parental systems, contractors' systems tend to differ by plants, thus make it difficult for contractors to design a standard system that is common to all relevant plants. Circumstances being as such, however, we have developed a system which is applicable to various customer utilities with minimal variations, using personal computers with database management and data communication softwares, with relatively low cost. We hope that this system will develop to the standard model for all Japanese contractors' personnel exposure management systems. (author)

  19. Corneal Toxicity Following Exposure to Asclepias Tuberosa.

    Science.gov (United States)

    Mikkelsen, Lauge Hjorth; Hamoudi, Hassan; Gül, Cigdem Altuntas; Heegaard, Steffen

    2017-01-01

    To present a case of corneal toxicity following exposure to milky plant latex from Asclepias tuberosa. A 70-year-old female presented with blurred vision and pain in her left eye after handling an Ascepias tuberosa . Clinical examination revealed a corneal stromal oedema with small epithelial defects. The corneal endothelium was intact and folds in Descemets membrane were observed. The oedema was treated with chloramphenicol, dexamethasone and scopolamine. The corneal oedema had appeared after corneal exposure to the plant, Asclepias tuberosa , whose latex contains cardenolides that inhibit the Na + / K + -ATPase in the corneal endothelium. The oedema resolved after 96 hours. After nine months the best corrected visual acuity was 20/20. Corneal toxicity has previously been reported for plants of the Asclepias family. This is a rare case describing severe corneal toxicity caused by exposure to latex from Asclepias tuberosa . Handling of plants of the Asclepias family should be kept as a differential diagnosis in cases of acute corneal toxicity.

  20. Glycopyrrolate in toxic exposure to ammonia gas

    Directory of Open Access Journals (Sweden)

    Bhalla A

    2011-01-01

    Full Text Available Ammonia (NH 3 is a highly water-soluble, colorless, irritant gas with a unique pungent odor. Liquid ammonia stored under high pressure is still widely used for refrigeration in cold stores used for storing grains. Severe toxicity may occur following accidental exposure. We report an interesting case of accidental exposure to ammonia treated with glycopyrrolate along with other supportive measures.

  1. Biological indicators of cadmium exposure and toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Shaikh, Z A; Smith, L M

    1986-01-01

    The increasing environmental and occupational exposure of populations to cadmium creates the need for biological indicators of cadmium exposure and toxicity. The advantages and disadvantages of monitoring blood cadmium, urinary, fecal, hair, and tissue cadmium, serum creatine, beta 2-microglobulin, alpha 1-anti-trypsin and other proteins, and urinary amino acids, enzymes, total proteins, glucose, beta 2-microglobulin, retinol-binding protein, lysozyme, and metallothionein are discussed. It is concluded that urinary cadmium, metallothionein and beta 2-microglubulin may be used together to assess cadmium exposure and toxicity. 66 references.

  2. Occupational Blood Exposure among Health Care Personnel and Hospital Trainees

    Directory of Open Access Journals (Sweden)

    M Hajjaji Darouiche

    2014-01-01

    Full Text Available Blood and body fluid Exposure is a major occupational safety problems for health care workers. Therefore, we conducted a descriptive and retrospective study to identify the characteristics of blood exposure accidents in health care settings which lasted five years (2005-2009 at the two university hospitals of Sfax. We have 593 blood exposure accidents in health care settings 152 (25.6% health personnel and 441 (74.4% trainees' doctors, nurses and health technicians. The mechanism of blood and body fluid exposure was accidental needle-stick injury in 78.9% of health staff, and 81% of trainees, accidental cut in 14.7% of health workers and 10.2% of trainees. The increasing severity of blood exposure accidents is linked to the lack of safe behavior against this risk.

  3. Occupational radiation exposure of the personnel due to interventional radiology

    International Nuclear Information System (INIS)

    Wucherer, M.; Schmidt, T.; Loose, R.

    2000-01-01

    Applications of interventional radiology continue to be on an upward trend, some countries reporting a 100% increase within 2-4 years, so that the resulting radiation exposure of both patients and personnel is an issue of increasing importance. Whereas those applications in general are of advantage for the patients, they mean just a further health hazard for the medical personnel. It is therefore necessary to exploit all available means to reduce the occupational doses. Modern interventional radiology systems offer a range of measures for this purpose, as e.g. last-image-hold, or pulsed modes. Special attention has to be given to the exposure of hand and head. Particularly the hand is closest to the useful beam, and it should be a mandatory requirement to wear film rings. (orig./CB) [de

  4. Minimizing employee exposure to toxic chemical releases

    International Nuclear Information System (INIS)

    Plummer, R.W.; Stobbe, T.J.; Mogensen, J.E.; Jeram, L.K.

    1987-01-01

    This book describes procedures for minimizing employee exposure to toxic chemical releases and suggested personal protective equipment (PPE) to be used in the event of such chemical release. How individuals, employees, supervisors, or companies perceive the risks of chemical exposure (risk meaning both probability of exposure and effect of exposure) determines to a great extent what precautions are taken to avoid risk. In Part I, the authors develop and approach which divides the project into three phases: kinds of procedures currently being used; the types of toxic chemical release accidents and injuries that occur; and, finally, integration of this information into a set of recommended procedures which should decrease the likelihood of a toxic chemical release and, if one does occur, will minimize the exposure and its severity to employees. Part II covers the use of personal protective equipment. It addresses the questions: what personal protective equipment ensembles are used in industry in situations where the release of a toxic or dangerous chemical may occur or has occurred; and what personal protective equipment ensembles should be used in these situations

  5. Radiation protection of aviation personnel at exposure by cosmic radiation

    International Nuclear Information System (INIS)

    Vicanova, M.; Pinter, I.; Liskova, A.

    2008-01-01

    For determination of radiation dose of aviation personnel we used the software EPCARD (European Program Package for the Calculation of Aviation Route Doses) developed by National Research Center for Environmental Health - Institute of Radiation Protection (Neuherberg, Germany) and the software CARI 6, developed by the FAA's Civil Aerospace Medical Institute (USA). Both codes are accomplished by the Joint Aviation Authorities. Experimental measurement and estimation of radiation doses of aviation personnel at exposure by cosmic radiation were realised in the period of lowered solar activity. All-year effective dose of pilots, which worked off at least 11 months exceeds the value 1 mSv in 2007. The mean all-year effective dose of member of aviation personnel at exposure by cosmic radiation is 2.5 mSv and maximal all-year effective dose, which we measured in 2007 was 4 mSv. We assumed that in the period of increased solar activity the all-year effective doses may by higher

  6. Corneal Toxicity Following Exposure to Asclepias Tuberosa

    DEFF Research Database (Denmark)

    Mikkelsen, Lauge Hjorth; Hamoudi, Hassan; Gül, Cigdem Altuntas

    2017-01-01

    PURPOSE: To present a case of corneal toxicity following exposure to milky plant latex from Asclepias tuberosa. METHODS: A 70-year-old female presented with blurred vision and pain in her left eye after handling an Ascepias tuberosa. Clinical examination revealed a corneal stromal oedema with small...... epithelial defects. The corneal endothelium was intact and folds in Descemets membrane were observed. The oedema was treated with chloramphenicol, dexamethasone and scopolamine. RESULTS: The corneal oedema had appeared after corneal exposure to the plant, Asclepias tuberosa, whose latex contains cardenolides...... that inhibit the Na+/ K+-ATPase in the corneal endothelium. The oedema resolved after 96 hours. After nine months the best corrected visual acuity was 20/20. CONCLUSION: Corneal toxicity has previously been reported for plants of the Asclepias family. This is a rare case describing severe corneal toxicity...

  7. Occupational overpressure exposure of breachers and military personnel

    Science.gov (United States)

    Kamimori, G. H.; Reilly, L. A.; LaValle, C. R.; Olaghere Da Silva, U. B.

    2017-11-01

    Military and law enforcement personnel may be routinely and repetitively exposed to low-level blast (LLB) overpressure during training and in operations. This repeated exposure has been associated with symptoms similar to that reported for sports concussion. This study reports LLB exposure for various military and law enforcement sources in operational training environments. Peak overpressure and impulse data are presented from indoor breaching, outdoor breaching, shotgun door breaching, small arms discharge, and mortar and artillery fire missions. Data were collected using the Black Box Biometrics (B3) Blast Gauge sensors. In all cases, sensors were attached to the operators and, where possible, also statically mounted to walls or other fixed structures. Peak overpressures from below 1 psi (7 kPa) to over 12 psi (83 kPa) were recorded; all values reported are uncorrected for incidence angle to the blast exposure source. The results of these studies indicate that the current minimum safe distance calculations are often inaccurate for both indoor and outdoor breaching scenarios as true environmental exposure can consistently exceed the 4 psi (28 kPa) incident safe threshold prescribed by U.S. Army doctrine. While ballistic (shotgun) door breaching and small arms firing only expose the operator to low peak exposure levels, the sheer number of rounds fired during training may result in an excessive cumulative exposure. Mortar and artillery crew members received significantly different overpressure and impulse exposures based on their position (job) relative to the weapon. As both the artillery and mortar crews commonly fire hundreds of rounds during a single training session they are also likely to receive high cumulative exposures. These studies serve to provide the research community with estimates for typical operator exposure across a range of operational scenarios or in the discharge of various weapons systems.

  8. Toxicity of middle distillates from dermal exposure.

    Science.gov (United States)

    Koschier, F J

    1999-02-01

    This report focuses on recent studies that investigated the effects of kerosine dermal exposure on neurotoxicity and reproductive/developmental toxicity. Background toxicity information will also be reviewed for kerosine range mid distillates. The kerosine range mid distillates have a carbon range of C9-C16 and have a boiling range of 302-554 degrees F (150-290 degrees C). This category includes kerosine, aviation fuels (e.g., Jet A, JP-5 and JP-8), no. 1 fuel oil and diesel fuel oil. In general, the kerosine range mid distillates demonstrate relatively low acute toxicity by any route of exposure. High inhalation exposures can induce central nervous system depression characterized by ataxia, hypoactivity and prostration. Kerosines are known to cause skin irritation and inflammation under conditions of acute and repeated exposure in animals and humans, but are only slightly irritating to the eye and are not skin sensitizers. In addition, the absorption of kerosine range mid distillates through the skin has been demonstrated to be fairly rapid, but limited to approximately 10-15% of the applied dose after 24 hours. The kerosine range mid distillates are generally inactive in genetic toxicity tests although positive studies have been reported. Positive results, while at times equivocal, have been reported for straight run kerosine and jet fuel A in the mouse lymphoma assay with metabolic activation, and hydrodesulfurized kerosine (mouse) and jet fuel A (rat) in the bone marrow cytogenetic assay. Effects on the nervous and reproductive systems have been reported in humans and experimental animals under conditions where inhalation and dermal exposure to specific kerosine type fuels are sometimes difficult to separate. Recent laboratory studies have addressed this point and examined the effects of dermal exposure. In these studies, rats were exposed to hydrodesulfurized kerosine by skin application to determine the potential of dermal contact to cause reproductive

  9. Characterization of inhalation exposure to jet fuel among U.S. Air Force personnel.

    Science.gov (United States)

    Merchant-Borna, Kian; Rodrigues, Ema G; Smith, Kristen W; Proctor, Susan P; McClean, Michael D

    2012-07-01

    Jet propulsion fuel-8 (JP-8) is the primary jet fuel used by the US military, collectively consuming ~2.5 billion gallons annually. Previous reports suggest that JP-8 is potentially toxic to the immune, respiratory, and nervous systems. The objectives of this study were to evaluate inhalation exposure to JP-8 constituents among active duty United States Air Force (USAF) personnel while performing job-related tasks, identify significant predictors of inhalation exposure to JP-8, and evaluate the extent to which surrogate exposure classifications were predictive of measured JP-8 exposures. Seventy-three full-time USAF personnel from three different air force bases were monitored during four consecutive workdays where personal air samples were collected and analyzed for benzene, ethylbenzene, toluene, xylenes, total hydrocarbons (THC), and naphthalene. The participants were categorized a priori into high- and low-exposure groups, based on their exposure to JP-8 during their typical workday. Additional JP-8 exposure categories included job title groups and self-reported exposure to JP-8. Linear mixed-effects models were used to evaluate predictors of personal air concentrations. The concentrations of THC in air were significantly different between a priori exposure groups (2.6 mg m(-3) in high group versus 0.5 mg m(-3) in low, P fuel distribution/maintenance, though self-reported exposure to JP-8 was an even stronger predictor of measured exposure in models that explained 72% (THC) and 67% (naphthalene) of between-worker variability. In fact, both self-report JP-8 exposure and a priori exposure groups explained more between-worker variability than job categories. Personal exposure to JP-8 varied by job and was positively associated with the relative humidity. However, self-reported exposure to JP-8 was an even stronger predictor of measured exposure than job title categories, suggesting that self-reported JP-8 exposure is a valid surrogate metric of exposure when

  10. Data processing of personnel exposure in TLD and film systems

    International Nuclear Information System (INIS)

    Lerner, A.; Liav, N.; Eisen, Y.

    1979-01-01

    The program for the processing and storage of data on the personnel irradiation exposure in Israel is built on the data base of the Weizmann Institute of Science; it is a general program suitable for both TLD and film dosimetry. The TSO system helped bring up-to-date the data of the various collections in an interactive way. The introduction of the TLD dosemeters in the badge service required certain changes in the thinking line - this because the TLD being a personal dosemeter is returned into service after having been deciphered. This demands following up the dosemeter when the worker moves from unit to unit or after he had finished his work. The program takes into account the internal exposures,too and conforms to the new recommendation published in ICRP-26. (B.G.)

  11. Situation of radiation exposure in medical personnel, (2)

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Minoru; Kumazaki, Hiroshi; Tsuchiya, Mitsuaki; Nakamura, Masamoto; Nonomura, Takuo [Tokyo Metropolitan Isotope Research Center (Japan)

    1982-09-01

    In connection with the radiation protection for medical personnel, the logarithmic normal distribution of their exposure doses has been examined, which is a prerequisite for the practice. The data were the doses measured by film badges from April, 1976, to March, 1981, for physicians, radiation technicians and nurses. The dose measurement by film badges was carried out monthly, 12 times a year; the values given were mrem/year. For the probability distribution of exposure doses, the following items were surveyed: comparison between three types of the profession and the kinds of film badges, i.e. for X-ray and ..gamma..-ray, the linearity of the logarithmic normal distribution for the types of medical institution, and comparison in the linearity between Japan and other countries. The fitting to linearity was found to be very good.

  12. Doses of emergency exposure to the USSR Navy personnel

    International Nuclear Information System (INIS)

    Skaletskiy, Yuriy

    2013-01-01

    Radiological consequences of the Soviet Navy accidents are significant and the number of acute radiation syndrome (ARS) cases is comparable to the number of ARS cases to Chernobyl catastrophe witness and clean-up workers in 1986. Results of a careful clinical-epidemiological examination of the personnel overexposed in the Navy accidents not only have value of radiobiology and radiation medicine specialists but can become a basis for the evaluation of the effectiveness of social protection strategy for the Chernobyl catastrophe clean-up workers. The officially registered exposure doses to persons affected by the Navy radiation accidents in some cases differ from the actual ones due to the imperfections of radiation monitoring facilities at the time of accidents. There was a tendency of clinical overstatement of the exposure doses resulting in diagnosis of 1st degree of ARS to persons who received external doses lower than 0.75. In some cases even 0.2 Gy was overstated as ARS severity for 2nd, 3rd, and 4th degrees. Exposure doses to the affected by the Navy accidents and their ARS severity degrees were evaluated with rather good accuracy. The use of modern method and approaches to the retrospective dose assessment allows more accurate evaluation of the submarine personnel exposure doses as well as verification of every ARS case, thus creating a necessary dosimetric basis for the organization of a correct radiation epidemiological investigation for persons of this contingent. Regretfully, tragic experience of nuclear power plants operation at the Navy vessels was not subject to analysis of specialists in order to improve nuclear safety, radiation protection, and emergency response organization in order to nuclear energy use in the USSR. (N.T.)

  13. Corneal Toxicity Following Exposure to Asclepias Tuberosa

    OpenAIRE

    Mikkelsen, Lauge Hjorth; Hamoudi, Hassan; G?l, Cigdem Altuntas; Heegaard, Steffen

    2017-01-01

    PURPOSE: To present a case of corneal toxicity following exposure to milky plant latex from Asclepias tuberosa.METHODS: A 70-year-old female presented with blurred vision and pain in her left eye after handling an Ascepias tuberosa. Clinical examination revealed a corneal stromal oedema with small epithelial defects. The corneal endothelium was intact and folds in Descemets membrane were observed. The oedema was treated with chloramphenicol, dexamethasone and scopolamine.RESULTS: The corneal ...

  14. Review of Phthalates Exposure and Toxicity

    Directory of Open Access Journals (Sweden)

    Samaneh Taghilou

    2015-12-01

    Full Text Available The dialkyl- or alkyl/aryl esters of 1, 2-benzenedicarboxylic acid, which are known as Phthalates, are high-production volume synthetic chemicals and considered as environmental pollutants, due to high production and uses in community, plastics industry and common consuming products. Di-(2-ethylhexyl phthalate (DEHP is the most abundant phthalate in the environment. Human exposure with DEHP could be done via different chemical compounds including food packaging, household furnishings, nutritional supplements, cleaning materials and insecticides. Besides, exposure of human with phthalates occurs through different pathways such as direct contact and using Phthalate-containing products, and indirectly through leaching into other products, or general environmental contaminations. Historically, the diet has been considered the major source of phthalate exposure in the general population, but in all sources, pathways, and their relative contributions to human exposures are not well understood. Medical devices are other source of significant exposure in human. Furthermore, cosmetics, personal care products, pharmaceuticals, nutritional supplements, herbal remedies and insecticides, may result in significant but poorly quantified human exposure with this compounds. In the present review article, we tried to discuss about metabolism of phthalates in human, toxicity, monitoring of phthalates in foods, environment, and cosmetic products and then metabolites of phthalates. Finally, evaluation of human exposure through biological control is discussed.

  15. The Association between Toxic Exposures and Chronic Multisymptom Illness in Veterans of the Wars of Iraq and Afghanistan

    Science.gov (United States)

    DeBeer, Bryann B.; Davidson, Dena; Meyer, Eric C.; Kimbrel, Nathan A.; Gulliver, Suzy B.; Morissette, Sandra B.

    2017-01-01

    Objective The purpose of this study was to determine if post-9/11 veterans deployed to the Iraq and Afghanistan conflicts experienced toxic exposures and whether they are related to symptoms of Chronic Multisymptom Illness (CMI). Methods Data from 224 post-9/11 veterans who self-reported exposure to hazards in theater were analyzed using hierarchical regression. Results Of the sample, 97.2% endorsed experiencing one or more potentially toxic exposure. In a regression model, toxic exposures and CMI symptoms were significantly associated above and beyond covariates. Follow-up analyses revealed that pesticide exposures, but not smoke inhalation was associated with CMI symptoms. Conclusions These findings suggest that toxic exposures were common among military personnel deployed to the most recent conflicts, and appear to be associated with CMI symptoms. Additional research on the impact of toxic exposures on returning Iraq and Afghanistan Veterans’ health is needed. PMID:28045798

  16. 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...

  17. [Tetrabromobisphenol A - Toxicity, environmental and occupational exposures].

    Science.gov (United States)

    Jarosiewicz, Monika; Bukowska, Bożena

    2017-02-28

    Brominated flame retardants (BFR), including tetrabromobisphenol A (TBBPA) represents 25% of the global market of flame retardants. Among them, TBBPA is used on the largest scale (approx. 60%) because of its firebreak properties and widespread occurrence in every day products such as furniture, upholstery, adhesives and electronic equipment. A broad application of TBBPA can contribute to environmental pollution. Tetrabromobisphenol A has been determined in soil, water, river sediments and the atmosphere. Tetrabromobisphenol A is characterized by a high value of coefficient n-octanol/water (log P = 4.5), low acidity, and it may exist in undissociated or dissociated form. Due to the high hydrophobicity, TBBPA may accumulate in living organisms, including humans at different food chain levels. The occurrence of TBBPA in humans, e.g., in blood, fat tissue and mother milk, has been reported. Tetrabromobisphenol A is classified as hazard statements (H) H400/H410, which means that it is toxic to aquatic biota, causing long-term changes in these organisms. Up to now, only a few studies have been conducted to assess potential toxicity of high doses of TBBPA to mammals. Although many people are occupationally exposed to TBBPA during production or processing of this substance in their workplaces, there are only a few studies that have assessed the real hazard associated with TBPPA exposure. The aim of the study was to discuss the latest literature (mainly from the years 2010-2016) referring to the presence of TBBPA in the environment and its effects to living organisms. Data concerning occupational exposure to TBBPA were also presented. Med Pr 2017;68(1):121-134. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  18. Radiation exposure of personnel in nuclear fuel facilities in fiscal 1981

    International Nuclear Information System (INIS)

    1983-01-01

    The owners of refining enterprises, fabrication enterprises and reprocessing enterprises and users are obligated by the law to keep the radiation exposure dose of personnel below the permissible level. In fiscal 1981 (from April, 1981, to March, 1982), the personnel exposure was far below this level. Exposure dose distribution, total exposure dose and average in the fiscal year are given for the personnel of the following enterprises and other personnel, respectively: refining enterprise - Power Reactor and Nuclear Fuel Development Corporation; fabrication enterprises - Mitsubishi Nuclear Fuel Co., Ltd., and four others; reprocessing enterprise - Power Reactor and Nuclear Fuel Development Corporation; users - Power Reactor and Nuclear Fuel Development Corporation, Japan Atomic Energy Research Institute, and four others. (Mori, K.)

  19. Personnel radiation exposure in the Asse saltmine repository during 1967 to 2008. Health monitoring Asse

    International Nuclear Information System (INIS)

    2011-02-01

    The health monitoring Asse includes the following chapters: Introduction, background information including handling of radioactive materials and radiation protection issues, data on radiation exposure (personnel dosimetry, incorporation surveillance, local dose rate measurements, exhaust monitoring, radioactivity in the salt mine air and in the brine, contamination), concept of the data base, interrogation of the personnel, quantification of the individual radiation doses, results of the radiation exposure quantification; significance of the results and perspectives.

  20. Radiation exposure of non-monitored hospital personnel

    International Nuclear Information System (INIS)

    Renaud, L.; Blanchette, J.; Galand, C.

    1993-02-01

    This addendum to report INFO--0437-1 reports the raw results of phase 2 of the survey of medical personnel exposed to nuclear medicine patients. It also presents floor plans of the three hospitals surveyed. (L.L.) (42 tabs., 36 figs.)

  1. Control in personnel exposure of RCD/FCD facility RLG during the period 2005 - 2008

    International Nuclear Information System (INIS)

    Murali, S.; Thanamani, S.; Sapkal, J.A.; Bairwa, Satya Manoj

    2010-01-01

    Full text: Radio Chemistry Wing, RLG, houses Radio Chemistry Division and Fuel Chemistry Division and certain common utility services. The personnel in the facility carry out radiochemical operations involving isotopes of Pu and other actinides. The HP Unit, Radio Chemistry Wing provides essential safety coverage to the personnel of the facility. The lab personnel of RCD/FCD facility at RLG carry out active operations, such operations held in suitable containment systems, under the HP supervision by RHC Unit advising safe work practices. The lab personnel are provided with monitoring programmes viz. TLD, Bio-assay and Lung counting periodically. Presently the dose limit for occupational exposure is 20 mSv per annum with 100 mSv for 5 consecutive calendar years. The present paper on TLD dose report enlists the details of the personnel exposure year wise and highlights the control in personnel exposure due to the safe procedures followed. The decreasing trend in the average personnel exposure over the period 2005 - 2008 validates the practice of adherence to safety procedures, though the amount of activity handled in the facility has increased by a few folds

  2. Control in personnel exposure at HIRUP facility during the period 2006-2010

    International Nuclear Information System (INIS)

    Ojha, Shashikala; Suman, Santosh Kumar; Murali, S.

    2012-01-01

    HIRUP facility is designed to handle MCi of 60 Co, fabrication of sealed source, is carried out in hot cell. The design safety features allow the handling of sealed sources and other gamma emitters under suitable containment systems. The NP Unit of the facility provides personnel monitoring programmes viz., TLD/DRD monitoring for the radiation workers. 60 Co and other gamma emitters pose mainly external hazard during the handling of sealed source in hot cell. TLD is processed to assess the external exposure of personnel. Air activity and gross bg contamination at the work place is periodically monitored and reported. The TLD users of HIRUP are periodically referred for internal monitoring - whole body counting and bio-assay to estimate internal exposure. There is no reported internal exposure so far. Personnel from IAD and BRIT facility are provided with personnel monitoring coverage by HP Unit; the TLD is issued with respective institution no. as - 0283, 4288. Each person gets identified by individual TLD number, renewed TLD issue on quarterly service period. Based on job requirement such as handling of high activity, additional Wrist TLDs are provided. The used TLD of IAD and BRIT are sent for processing. The dose report obtained, enlists personnel exposure details. HP Unit does the report making to the concerned agencies enlisting the operational status, total occupational exposure of the facility (person mSv), average exposure (mSv) and few other details. Details of exposure for 2006 - 2010 (non-zero exposure cases), indicate that for IAD collective exposure got reduced by 78.5 %, average exposure got reduced by 62.6 %; for BRIT collective exposure got reduced by 58.2 %, average exposure got reduced by 46.8 %, at HIRUP facility. There is a decreasing trend in personnel exposure over the period 2006-2010, is due to HP safety protocol, on job HP surveillance and related safety measures. The personnel exposure is controlled as per ALARA, decreasing trend in the

  3. Methodology of personnel exposure calculation and optimisation within the decommissioning planning code OMEGA

    International Nuclear Information System (INIS)

    Vasko, Marek; Daniska, Vladimir; Rehak, Ivan; Necas, Vladimir

    2011-01-01

    Calculation of personnel exposure is a one of the main parameters being evaluated within the pre-decommissioning plans together with other decommissioning drivers such as costs, manpower, amounts of RAW and conventional waste and amount of discharged gaseous and liquid effluents. Alongside with manpower, the exposure is an indicator of the decommissioning process for need of staff, and quantifies impact of decommissioning on personnel from the radio hygienic point of view. At the same time it indicates suitability of individual work procedures use for decommissioning activities. For this reason it is important to estimate as precise as possible demands on personnel exposure even during preparatory decommissioning phase to quantify impact of decommissioning on personnel and eventually optimize the decommissioning process, if needed. The most appropriate way of staff exposure estimation during decommissioning preparatory phases is its calculation based on radiological and physical characteristics of equipment to be decommissioned and also quantitative and qualitative characterisation of typical decommissioning activities. On one hand, the methodology of exposure calculation should allow as much as possible realistic description and algorithmisation of exposure ways during decommissioning activities. On the other hand the calculation have to be systematic, well-arranged and clearly definable by appropriate mathematic relations. Calculation can be made by various approaches using more or less sophisticated software solutions from classic MS Excel sheets up to the complex calculation codes. In this paper, a methodology used for personnel exposure calculation and optimization implemented within the complex computer code OMEGA developed at DECOM, a.s. is described. (author)

  4. Recovery of anaerobic digestion after exposure to toxicants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Yang, J.; Parkin, G.F.; Speece, R.E.

    1979-12-01

    The concept that methane fermentation cannot tolerate chronic or slug doses of toxicants has almost totally precluded methane fermentation as a viable contender for the treatment of industrial wastewaters. This study assayed a wide variety of toxicants, heavy metals, inorganic salts, organic chemicals, solvents, and antibiotics which are used in industrial processes and, therefore, appear in the industrial wastewaters therefrom. Toxicity was related to the reduction in methane production of a control containing no toxicant. The response of methane fermentation after exposure to a toxicant was assayed with unacclimated cultures as well as cultures which had been acclimated to increasing concentrations of the toxicant over long periods of time. The reversible nature of the toxicants was assayed by adding slug doses to plug flow anaerobic filters and recording gas production prior to, during, and after toxicant addition.

  5. Occupational exposure to the personnel regarded by NRB-76/87 to B category

    Energy Technology Data Exchange (ETDEWEB)

    Gubatova, D; Balode, G; Nemiro, E [Medical Institute, Riga (USSR)

    1990-01-01

    During the decades use of radioactive sources in all branches of national economy has increased. Due to this tendency the number of exposed individuals from artificial sources including those exposed only occasionally (the so-called B category) increases. For this category the personnel dosimetry is not obligatory, and radioactive monitoring of their working and living places would do. Nevertheless, the thermoluminescent personnel monitoring data derived by us show that occupational exposure of this category is near, and occasionally even higher than B category exposure limit. So, for example, anesthesiologists annual exposure makes 4.5 mSv, that of surgeons 6.5 mSv, of anesthetic nurses 4.0 mSv (Traumatological and Orthopedic Institute personnel). Annual exposure of 'Medtekhnika' factory electromechanics ought to repair, set up and check up X-ray devices in 1987 was 5 mSv. (author).

  6. Assessment of the occupational exposure of the INOR personnel

    International Nuclear Information System (INIS)

    Villa Zulueta, R.; Cardenas Herrera, J.

    1996-01-01

    The paper evaluate the levels of exposure to ionizing radiation and their influence on the health of occupationally exposed workers from the National Institute of Oncology and Radiobiology during the 1980.1988 period

  7. Study of the radio-exposure of the personnel in diagnostic and interventional radio-cardiology

    International Nuclear Information System (INIS)

    Musnier, J.

    1998-01-01

    The renewal of radiological materials has contributed to reduce significantly the doses received by the personnel. The installations of low shutters and lead windows give an important potential of reduction of doses received by the physicians. For the medical and para medical personnel, a modification of working habits must lead to an important exposure reduction. To summarize, the medical and para medical personnel in cardiology has at one s disposal all the means allowing to reach the objective of dose constraints. The radiation protection optimization now depends on every concerned actor. (N.C.)

  8. Developmental toxicity of prenatal exposure to toluene.

    Science.gov (United States)

    Bowen, Scott E; Hannigan, John H

    2006-01-01

    Organic solvents have become ubiquitous in our environment and are essential for industry. Many women of reproductive age are increasingly exposed to solvents such as toluene in occupational settings (ie, long-term, low-concentration exposures) or through inhalant abuse (eg, episodic, binge exposures to high concentrations). The risk for teratogenic outcome is much less with low to moderate occupational solvent exposure compared with the greater potential for adverse pregnancy outcomes, developmental delays, and neurobehavioral problems in children born to women exposed to high concentrations of abused organic solvents such as toluene, 1,1,1-trichloroethane, xylenes, and nitrous oxide. Yet the teratogenic effects of abuse patterns of exposure to toluene and other inhalants remain understudied. We briefly review how animal models can aid substantially in clarifying the developmental risk of exposure to solvents for adverse biobehavioral outcomes following abuse patterns of use and in the absence of associated health problems and co-drug abuse (eg, alcohol). Our studies also begin to establish the importance of dose (concentration) and critical perinatal periods of exposure to specific outcomes. The present results with our clinically relevant animal model of repeated, brief, high-concentration binge prenatal toluene exposure demonstrate the dose-dependent effect of toluene on prenatal development, early postnatal maturation, spontaneous exploration, and amphetamine-induced locomotor activity. The results imply that abuse patterns of toluene exposure may be more deleterious than typical occupational exposure on fetal development and suggest that animal models are effective in studying the mechanisms and risk factors of organic solvent teratogenicity.

  9. Noise exposure and cognitive performance: A study on personnel on board Royal Norwegian Navy vessels

    Directory of Open Access Journals (Sweden)

    Kaja Irgens-Hansen

    2015-01-01

    Full Text Available Prior research shows that work on board vessels of the Royal Norwegian Navy (RNoN is associated with noise exposure levels above recommended standards. Further, noise exposure has been found to impair cognitive performance in environmental, occupational, and experimental settings, although prior research in naval and maritime settings is sparse. The aim of this study was to evaluate cognitive performance after exposure to noise among personnel working on board vessels in the RNoN. Altogether 87 Navy personnel (80 men, 7 women; 31 ± 9 years from 24 RNoN vessels were included. Noise exposure was recorded by personal noise dosimeters at a minimum of 4 h prior to testing, and categorized into 4 groups for the analysis: 85.2 dB(A. The participants performed a visual attention test based on the Posner cue-target paradigm. Multivariable general linear model (GLM analyses were performed to analyze whether noise exposure was associated with response time (RT when adjusting for the covariates age, alertness, workload, noise exposure in test location, sleep the night before testing, use of hearing protection device (HPD, and percentage of errors. When adjusting for covariates, RT was significantly increased among personnel exposed to >85.2 dB(A and 77.1-85.2 dB(A compared to personnel exposed to <72.6 dB(A.

  10. Noise exposure and cognitive performance: A study on personnel on board Royal Norwegian Navy vessels.

    Science.gov (United States)

    Irgens-Hansen, Kaja; Gundersen, Hilde; Sunde, Erlend; Baste, Valborg; Harris, Anette; Bråtveit, Magne; Moen, Bente E

    2015-01-01

    Prior research shows that work on board vessels of the Royal Norwegian Navy (RNoN) is associated with noise exposure levels above recommended standards. Further, noise exposure has been found to impair cognitive performance in environmental, occupational, and experimental settings, although prior research in naval and maritime settings is sparse. The aim of this study was to evaluate cognitive performance after exposure to noise among personnel working on board vessels in the RNoN. Altogether 87 Navy personnel (80 men, 7 women; 31 ± 9 years) from 24 RNoN vessels were included. Noise exposure was recorded by personal noise dosimeters at a minimum of 4 h prior to testing, and categorized into 4 groups for the analysis: 85.2 dB(A). The participants performed a visual attention test based on the Posner cue-target paradigm. Multivariable general linear model (GLM) analyses were performed to analyze whether noise exposure was associated with response time (RT) when adjusting for the covariates age, alertness, workload, noise exposure in test location, sleep the night before testing, use of hearing protection device (HPD), and percentage of errors. When adjusting for covariates, RT was significantly increased among personnel exposed to >85.2 dB(A) and 77.1-85.2 dB(A) compared to personnel exposed to <72.6 dB(A).

  11. Guilt is more strongly associated with suicidal ideation among military personnel with direct combat exposure.

    Science.gov (United States)

    Bryan, Craig J; Ray-Sannerud, Bobbie; Morrow, Chad E; Etienne, Neysa

    2013-05-15

    Suicide rates in the U.S. military have been rising rapidly in the past decade. Research suggests guilt is a significant predictor of suicidal ideation among military personnel, and may be especially pronounced among those who have been exposure to combat-related traumas. The current study explored the interactive effect of direct combat exposure and guilt on suicidal ideation in a clinical sample of military personnel. Ninety-seven active duty U.S. Air Force personnel receiving outpatient mental health treatment at two military clinics completed self-report symptom measures of guilt, depression, hopelessness, perceived burdensomeness, posttraumatic stress disorder, and suicidal ideation. Generalized multiple regression analyses indicated a significant interaction of guilt and direct combat exposure (B=.124, SE=.053, p=.020), suggesting a stronger relationship of guilt with suicidal ideation among participants who had direct combat exposure as compared to those who had not. The interactions of direct combat exposure with depression (B=.004, SE=.040, p=.926), PTSD symptoms (B=.016, SE=.018, p=.382), perceived burdensomeness (B=.159, SE=.152, p=.300) and hopelessness (B=.069, SE=.036, p=.057) were nonsignificant. Although guilt is associated with more severe suicidal ideation in general among military personnel, it is especially pronounced among those who have had direct combat exposure. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Radiation exposure of non-monitored hospital personnel

    International Nuclear Information System (INIS)

    Renaud, L.; Blanchette, J.; Galand, C.

    1993-02-01

    This project investigated the radiological impact of nuclear medicine patients on non-monitored personnel in hospital environments. More than 800 workers and 135 specific areas in three Quebec hospitals were surveyed daily during a six-month period with Geiger counters, TLD badges, and TLD chips. Average dose rates of up to 2.2 μSv/h were measured in some waiting areas. The radiation level of a nursing unit is a direct function of the ambulatory radioactivity carried by nuclear medicine patients. Three percent of the workers surveyed had a work-related dose in excess of 0.3 mSv/6 months (maximum 1.4 mSv/6 months). Over 88 percent were in the range between local background and 0.3 mSv/6 months. Less than 4 percent belong to groups of workers who were exposed to a level indistinguishable from background. Thus many workers surveyed in this study receive a work-related dose similar to those of medical workers monitored by Health and Welfare Canada. The average annual dose for these workers was 104 person-millisieverts. The authors recommend: better management of radioactive patients; the provision of information and education for all hospital workers having regular contact with radioactive patients; and the facilitation of the identification of nuclear medicine patients within the hospital environment. (28 tabs., 23 figs.)

  13. ALARA and de minimis concepts in regulation of personnel exposure

    International Nuclear Information System (INIS)

    Baum, J.W.

    1987-01-01

    The ALARA process should not be limited by a de minimis level on either collective or individual dose, but should be limited or defined by an acceptable discount-rate on future costs and effects, and a monetary value for detriment, to be used in cost-effectiveness or cost-benefit calculations at dose levels well below the regulatory limits. This approach would provide the desired benefit of simplifying the decision process, it makes it more cost effective, and would avoid the inconsistencies of limits on only one of the four parameters of importance in the optimization process. These are average individual effective dose equivalent rate, number of individuals to be included in the summation, years of exposure, and costs, which include costs of analysis to reduce the exposure. This approach emphasizes that these doses to an individual may not be considered trivial by society when given to a very large population, especially if they could easily be avoided. 32 refs., 2 tabs

  14. Dosimetry of the Occupational Exposure Personnel and not exposure of the INNSZ

    International Nuclear Information System (INIS)

    Ruiz J, A.

    1999-01-01

    In this work, was measured the equivalent dose of all the personnel of Nuclear medicine and personnel of the Institute which by its activities remain in the Department, by time determined, through thermoluminescent dosemeters and the results were that the personnel presents variable equivalent dose and it is proportional to the time and radionuclide type which use for their work. By this it is allowed to secure what the work watched with respect to radiological protection to fulfil with the International Standards standing for personnel in the Institute. (Author)

  15. Study of morbidity of personnel with potential exposure to vinclozolin.

    Science.gov (United States)

    Zober, A; Hoffmann, G; Ott, M G; Will, W; Germann, C; van Ravenzwaay, B

    1995-01-01

    OBJECTIVES--To examine internal exposure and targeted health outcomes of employees exposed to 3-(3,5-dichlorophenyl)-5-methyl-5-vinyl-1,3-oxazolidine-2,4-dione; chemical abstracts service (CAS) number: 50471-44-8 (vinclozolin). METHODS--A cross sectional study of 67 men exposed to vinclozolin for one to 13 years during synthesis and formulation operations and 52 controls. Biomonitoring was based on determination of urinary metabolites that contained a 3,5-dichloroaniline (3,5-DCA) moiety. Targeted health endpoints were the same as in previous subchronic and chronic animal studies--namely, reversible changes in the concentrations of hormones of the adrenocorticotrophic and gonadotrophic feedback systems, signs of liver injury, haemolytic anaemia, cataract formation (uniquely in rats), and hormonally induced hyperplasia and tumours at high doses. The clinical investigation consisted of a medical and occupational history questionnaire, physical examination, laboratory determinations (including testosterone, LH, and FSH measurements), ultrasonography of the liver and prostate, a detailed eye examination, and routine spirometry. RESULTS--The mean 3,5-DCA concentration for two thirds of the study group exceeded an equivalent of the vinclozolin acceptable daily intake (ADI) used for consumer regulatory purposes. Even the highest concentrations were, however, at least 10 times below the no observable adverse effect level (NOAEL) based on animal studies. Analysis of physical examination and laboratory data provided no evidence of hormonal responses induced by vinclozolin. Furthermore, no evidence of liver injury, prostate changes, cataract formation, or haemolytic anaemia was found. CONCLUSION--There was no evidence of any health effects induced by vinclozolin among employees with potential long term exposure. In particular, no antiandrogenic effects were found. PMID:7795738

  16. Radiation exposure to patients and personnel during percutaneous renal calculus extraction

    International Nuclear Information System (INIS)

    Khandelwal, K.C.; Kooka, D.M.; Dagaonkar, S.S.; Supe, S.J.

    1990-01-01

    Radiation exposure to the patient, radiologist and other personnel was measured during 20 percutaneous renal calculus extractions. Thermoluminescent dosimeters were used. The average skin dose for patient at the level of the testis was 80 mrem, and at the level of the kidney, 17.2 rem. Radiation exposure to the personnel was measured at the levels of forehead, thyroid, chest and testis. The average dose to these regions ranged between 0.20 mrem and 2.5 mrem. The radiologist's hand received on average radiation of 88.8 mrems. The patient skin surface exposure at the nephrostomy site are comparable to skin doses from standard procedures. The exposure to the radiologist is similar to that from other interventional fluoroscopic procedures and is within acceptable limits. (author). 10 refs., 3 tabs

  17. Occupational exposure to ambient electromagnetic fields of technical operational personnel working for a mobile telephone operator

    International Nuclear Information System (INIS)

    Chauvin, S.; Gibergues, M. L.; Wuethrich, G.; Picard, D.; Desreumaux, J. P.; Bouillet, J. C.

    2009-01-01

    In order to investigate the exposure of operational personnel to radiofrequency electromagnetic fields when working for a mobile telephone operator, exposimeters were used to make individual records on 23 Technical Operations personnel (mobile telephone maintenance staff) and also on 22 Other Workers. The exposure densities, to which each of the 45 subjects was subjected, were quantified using 229 exposure indicators. Cluster analysis techniques were applied to the data, in an attempt to show that they would re-emerge as belonging to one of the two groups, i.e. the Technical Operational Personnel group or the Other Workers group. This exploratory investigation has shown that the cluster analysis does not reveal a sufficiently reliable emergence of the two groups, even though certain exposure indicators were significantly different for the two groups. In addition, the use of a Learning Group method does not lead to the discovery of a predictive law that could identify the Technical Operational Personnel as a sub-group within the overall group. (authors)

  18. Exposure of hospital operating room personnel to potentially harmful environmental agents

    International Nuclear Information System (INIS)

    Sass-Kortsak, A.M.; Purdham, J.T.; Bozek, P.R.; Murphy, J.H.

    1992-01-01

    Epidemiologic studies of risk to reproductive health arising from the operating room environment have been inconclusive and lack quantitative exposure information. This study was undertaken to quantify exposure of operating room (OR) personnel to anesthetic agents, x-radiation, methyl methacrylate, and ethylene oxide and to determine how exposure varies with different operating room factors. Exposures of anesthetists and nurses to these agents were determined in selected operating rooms over three consecutive days. Each subject was asked to wear an x-radiation dosimeter for 1 month. Exposure to anesthetic agents was found to be influenced by the age of the OR facility, type of surgical service, number of procedures carried out during the day, type of anesthetic circuitry, and method of anesthesia delivery. Anesthetists were found to have significantly greater exposures than OR nurses. Exposure of OR personnel to ethylene oxide, methyl methacrylate, and x-radiation were well within existing standards. Exposure of anesthetists and nurses to anesthetic agents, at times, was in excess of Ontario exposure guidelines, despite improvements in the control of anesthetic pollution

  19. Influence of exposure time on toxicity-An overview.

    Science.gov (United States)

    Connell, Des W; Yu, Qiming J; Verma, Vibha

    2016-04-29

    Data on toxicity of chemicals is usually reported as the LD50, or LC50, with the exposure time from experimental testing in the laboratory reported. But the exposure time is not considered to be a quantifiable variable which can be used to evaluate its importance in expressed toxicity, often described in general terms such as acute, chronic and so on. For the last hundred years Habers Rule has been successfully used to extrapolate from reported exposure times to other exposure times which may be needed for setting standards, health risk assessments and other applications. But it has limitations particularly in environmental applications where exposure levels are low and exposure times are relatively long. The Reduced Life Expectancy (RLE) model overcomes these problems and can be utilised under all exposure conditions. It can be expressed as ln(LT50)=-a (LC50)(ν)+b where the constants ν, a and b can be evaluated by fitting the model to experimental data on the LC50, and corresponding LT50, together with the Normal Life Expectancy (NLE) of the organism being considered as a data point when the LC50 is zero. The constant, ν, at a value of unity gives a linear relationship and where νmodel for fish, invertebrates and mammals involving 115 data sets and with a wide range of organic and inorganic toxicants the RLE model gave correlation coefficients of >0.8 with 107 sets of data. The RLE model can be used to extrapolate from a limited data set on exposure times and corresponding LT50 values to any exposure time and corresponding LT50 value. The discrepancy between Haber's Rule and RLE model increases as the exposure time increases. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  20. Pulmonary toxicity after exposure to military-relevant heavy metal tungsten alloy particles

    International Nuclear Information System (INIS)

    Roedel, Erik Q.; Cafasso, Danielle E.; Lee, Karen W.M.; Pierce, Lisa M.

    2012-01-01

    Significant controversy over the environmental and public health impact of depleted uranium use in the Gulf War and the war in the Balkans has prompted the investigation and use of other materials including heavy metal tungsten alloys (HMTAs) as nontoxic alternatives. Interest in the health effects of HMTAs has peaked since the recent discovery that rats intramuscularly implanted with pellets containing 91.1% tungsten/6% nickel/2.9% cobalt rapidly developed aggressive metastatic tumors at the implantation site. Very little is known, however, regarding the cellular and molecular mechanisms associated with the effects of inhalation exposure to HMTAs despite the recognized risk of this route of exposure to military personnel. In the current study military-relevant metal powder mixtures consisting of 92% tungsten/5% nickel/3% cobalt (WNiCo) and 92% tungsten/5% nickel/3% iron (WNiFe), pure metals, or vehicle (saline) were instilled intratracheally in rats. Pulmonary toxicity was assessed by cytologic analysis, lactate dehydrogenase activity, albumin content, and inflammatory cytokine levels in bronchoalveolar lavage fluid 24 h after instillation. The expression of 84 stress and toxicity-related genes was profiled in lung tissue and bronchoalveolar lavage cells using real-time quantitative PCR arrays, and in vitro assays were performed to measure the oxidative burst response and phagocytosis by lung macrophages. Results from this study determined that exposure to WNiCo and WNiFe induces pulmonary inflammation and altered expression of genes associated with oxidative and metabolic stress and toxicity. Inhalation exposure to both HMTAs likely causes lung injury by inducing macrophage activation, neutrophilia, and the generation of toxic oxygen radicals. -- Highlights: ► Intratracheal instillation of W–Ni–Co and W–Ni–Fe induces lung inflammation in rats. ► W–Ni–Co and W–Ni–Fe alter expression of oxidative stress and toxicity genes. ► W

  1. Nickel Nanoparticles Exposure and Reproductive Toxicity in Healthy Adult Rats

    Directory of Open Access Journals (Sweden)

    Lu Kong

    2014-11-01

    Full Text Available Nickel is associated with reproductive toxicity. However, the reproductive toxicity of nickel nanoparticles (Ni NPs is unclear. Our goal was to determine the association between nickel nanoparticle exposure and reproductive toxicity. According to the one-generation reproductive toxicity standard, rats were exposed to nickel nanoparticles by gavage and we selected indicators including sex hormone levels, sperm motility, histopathology, and reproductive outcome etc. Experimental results showed nickel nanoparticles increased follicle stimulating hormone (FSH and luteinizing hormone (LH, and lowered etradiol (E2 serum levels at a dose of 15 and 45 mg/kg in female rats. Ovarian lymphocytosis, vascular dilatation and congestion, inflammatory cell infiltration, and increase in apoptotic cells were found in ovary tissues in exposure groups. For male rats, the weights decreased gradually, the ratio of epididymis weight over body weight increased, the motility of rat sperm changed, and the levels of FSH and testosterone (T diminished. Pathological results showed the shedding of epithelial cells of raw seminiferous tubule, disordered arrangement of cells in the tube, and the appearance of cell apoptosis and death in the exposure group. At the same time, Ni NPs resulted in a change of the reproductive index and the offspring development of rats. Further research is needed to elucidate exposure to human populations and mechanism of actions.

  2. Nickel nanoparticles exposure and reproductive toxicity in healthy adult rats.

    Science.gov (United States)

    Kong, Lu; Tang, Meng; Zhang, Ting; Wang, Dayong; Hu, Ke; Lu, Weiqi; Wei, Chao; Liang, Geyu; Pu, Yuepu

    2014-11-17

    Nickel is associated with reproductive toxicity. However, the reproductive toxicity of nickel nanoparticles (Ni NPs) is unclear. Our goal was to determine the association between nickel nanoparticle exposure and reproductive toxicity. According to the one-generation reproductive toxicity standard, rats were exposed to nickel nanoparticles by gavage and we selected indicators including sex hormone levels, sperm motility, histopathology, and reproductive outcome etc. Experimental results showed nickel nanoparticles increased follicle stimulating hormone (FSH) and luteinizing hormone (LH), and lowered etradiol (E2) serum levels at a dose of 15 and 45 mg/kg in female rats. Ovarian lymphocytosis, vascular dilatation and congestion, inflammatory cell infiltration, and increase in apoptotic cells were found in ovary tissues in exposure groups. For male rats, the weights decreased gradually, the ratio of epididymis weight over body weight increased, the motility of rat sperm changed, and the levels of FSH and testosterone (T) diminished. Pathological results showed the shedding of epithelial cells of raw seminiferous tubule, disordered arrangement of cells in the tube, and the appearance of cell apoptosis and death in the exposure group. At the same time, Ni NPs resulted in a change of the reproductive index and the offspring development of rats. Further research is needed to elucidate exposure to human populations and mechanism of actions.

  3. Thermoregulatory responses to environmental toxicants: The interaction of thermal stress and toxicant exposure

    International Nuclear Information System (INIS)

    Leon, Lisa R.

    2008-01-01

    Thermal stress can have a profound impact on the physiological responses that are elicited following environmental toxicant exposure. The efficacy by which toxicants enter the body is directly influenced by thermoregulatory effector responses that are evoked in response to high ambient temperatures. In mammals, the thermoregulatory response to heat stress consists of an increase in skin blood flow and moistening of the skin surface to dissipate core heat to the environment. These physiological responses may exacerbate chemical toxicity due to increased permeability of the skin, which facilitates the cutaneous absorption of many environmental toxicants. The core temperature responses that are elicited in response to high ambient temperatures, toxicant exposure or both can also have a profound impact on the ability of an organism to survive the insult. In small rodents, the thermoregulatory response to thermal stress and many environmental toxicants (such as organophosphate compounds) is often biphasic in nature, consisting initially of a regulated reduction in core temperature (i.e., hypothermia) followed by fever. Hypothermia is an important thermoregulatory survival strategy that is used by small rodents to diminish the effect of severe environmental insults on tissue homeostasis. The protective effect of hypothermia is realized by its effects on chemical toxicity as molecular and cellular processes, such as lipid peroxidation and the formation of reactive oxygen species, are minimized at reduced core temperatures. The beneficial effects of fever are unknown under these conditions. Perspective is provided on the applicability of data obtained in rodent models to the human condition

  4. [Toxic nephropathy secondary to occupational exposure to metallic mercury].

    Science.gov (United States)

    Voitzuk, Ana; Greco, Vanina; Caputo, Daniel; Alvarez, Estela

    2014-01-01

    Toxic nephrophaties secondary to occupational exposure to metals have been widely studied, including membranous nephropathy by mercury, which is rare. Occupational poisoning by mercury is frequent, neurological symptoms are the main form of clinical presentation. Secondary renal involvement in chronic exposure to metallic mercury can cause glomerular disease by deposit of immune-complexes. Membranous glomerulopathy and minimal change disease are the most frequently reported forms. Here we describe the case of a patient with occupational exposure to metallic mercury, where nephrotic syndrome due to membranous glomerulonephritis responded favorably to both chelation and immunosuppressive therapy.

  5. Exploratory breath analyses for assessing toxic dermal exposures of firefighters during suppression of structural burns.

    Science.gov (United States)

    Pleil, Joachim D; Stiegel, Matthew A; Fent, Kenneth W

    2014-09-01

    Firefighters wear fireproof clothing and self-contained breathing apparatus (SCBA) during rescue and fire suppression activities to protect against acute effects from heat and toxic chemicals. Fire services are also concerned about long-term health outcomes from chemical exposures over a working lifetime, in particular about low-level exposures that might serve as initiating events for adverse outcome pathways (AOP) leading to cancer. As part of a larger US National Institute for Occupational Safety and Health (NIOSH) study of dermal exposure protection from safety gear used by the City of Chicago firefighters, we collected pre- and post-fire fighting breath samples and analyzed for single-ring and polycyclic aromatic hydrocarbons as bioindicators of occupational exposure to gas-phase toxicants. Under the assumption that SCBA protects completely against inhalation exposures, any changes in the exhaled profile of combustion products were attributed to dermal exposures from gas and particle penetration through the protective clothing. Two separate rounds of firefighting activity were performed each with 15 firefighters per round. Exhaled breath samples were collected onto adsorbent tubes and analyzed with gas-chromatography-mass spectrometry (GC-MS) with a targeted approach using selective ion monitoring. We found that single ring aromatics and some PAHs were statistically elevated in post-firefighting samples of some individuals, suggesting that fire protective gear may allow for dermal exposures to airborne contaminants. However, in comparison to a previous occupational study of Air Force maintenance personnel where similar compounds were measured, these exposures are much lower suggesting that firefighters' gear is very effective. This study suggests that exhaled breath sampling and analysis for specific targeted compounds is a suitable method for assessing systemic dermal exposure in a simple and non-invasive manner.

  6. Urinary biomarkers of occupational jet fuel exposure among Air Force personnel.

    Science.gov (United States)

    Smith, Kristen W; Proctor, Susan P; Ozonoff, A L; McClean, Michael D

    2012-01-01

    There is a potential for widespread occupational exposure to jet fuel among military and civilian personnel. Urinary metabolites of naphthalene have been suggested for use as short-term biomarkers of exposure to jet fuel (jet propulsion fuel 8 (JP8)). In this study, urinary biomarkers of JP8 were evaluated among US Air Force personnel. Personnel (n=24) were divided a priori into high, moderate, and low exposure groups. Pre- and post-shift urine samples were collected from each worker over three workdays and analyzed for metabolites of naphthalene (1- and 2-naphthol). Questionnaires and breathing-zone naphthalene samples were collected from each worker during the same workdays. Linear mixed-effects models were used to evaluate the exposure data. Post-shift levels of 1- and 2-naphthol varied significantly by a priori exposure group (levels in high group>moderate group>low group), and breathing-zone naphthalene was a significant predictor of post-shift levels of 1- and 2-naphthol, indicating that for every unit increase in breathing-zone naphthalene, there was an increase in naphthol levels. These results indicate that post-shift levels of urinary 1- and 2-naphthol reflect JP8 exposure during the work-shift and may be useful surrogates of JP8 exposure. Among the high exposed workers, significant job-related predictors of post-shift levels of 1- and 2-naphthol included entering the fuel tank, repairing leaks, direct skin contact with JP8, and not wearing gloves during the work-shift. The job-related predictors of 1- and 2-naphthol emphasize the importance of reducing inhalation and dermal exposure through the use of personal protective equipment while working in an environment with JP8.

  7. Inhalation Exposure to Jet Fuel (JP8) Among U.S. Air Force Personnel

    Science.gov (United States)

    2010-10-01

    are occupationally exposcd.(I) )nfonnation on the health consequences o f human exposure 10 JP8 is limited.(I·2) though there is some evidence that...JP8 may be toxic to the immune system. respirdtory trdCt, and nervous system at exposure concentrations ncar 350 mg/m·1.m The current ACG lH...Egeghy et al.(7) and to reflect a scheme that may be used in epidemiologic studies assessing exposure and hcalth outcomes . The high exposure group

  8. Development of automated equipment for reduction of personnel radiation exposure in nuclear power plants

    International Nuclear Information System (INIS)

    Ogushi, Akira; Fujii, Masaaki; Mizuno, Katsuhiro.

    1976-01-01

    Described are a mobile remote inspection system and an automatic analyzer for radioactive nuclides in reactor coolant now being developed as a means of reducing personnel radiation exposure in nuclear power plants. In the mobile remote inspection system ''TELEPAT'', a self-propelled vehicle equipped with a thermometer, accelerometer, microphone, ionization chamber, etc. is remote operated from the main control room to inspect the equipment in the reactor building. The automatic analyzer for radioactive nuclides in reactor coolant automates the series of operations ranging from sampling of reactor coolant to measurement of radioactivity and analyses of measured data, with a view to saving labor in radioactivity analysis work while reducing exposure of personnel to radiation. (auth.)

  9. Inhalation exposure to jet fuel (JP8) among U.S. Air Force personnel.

    Science.gov (United States)

    Smith, Kristen W; Proctor, Susan P; Ozonoff, Al; McClean, Michael D

    2010-10-01

    As jet fuel is a common occupational exposure among military and civilian populations, this study was conducted to characterize jet fuel (JP8) exposure among active duty U.S. Air Force personnel. Personnel (n = 24) were divided a priori into high, moderate, and low exposure groups. Questionnaires and personal air samples (breathing zone) were collected from each worker over 3 consecutive days (72 worker-days) and analyzed for total hydrocarbons (THC), benzene, toluene, ethylbenzene, xylenes, and naphthalene. Air samples were collected from inside the fuel tank and analyzed for the same analytes. Linear mixed-effects models were used to evaluate the exposure data. Our results show that the correlation of THC (a measure of overall JP8 inhalation exposure) with all other analytes was moderate to strong in the a priori high and moderate exposure groups combined. Inhalation exposure to all analytes varied significantly by self-reported JP8 exposure (THC levels higher among workers reporting JP8 exposure), a priori exposure group (THC levels in high group > moderate group > low group), and more specific job task groupings (THC levels among workers in fuel systems hangar group > refueling maintenance group > fuel systems office group > fuel handling group > clinic group), with task groupings explaining the most between-worker variability. Among highly exposed workers, statistically significant job task-related predictors of inhalation exposure to THC indicated that increased time in the hangar, working close to the fuel tank (inside > less than 25 ft > greater than 25 ft), primary job (entrant > attendant/runner/fireguard > outside hangar), and performing various tasks near the fuel tank, such as searching for a leak, resulted in higher JP8 exposure. This study shows that while a priori exposure groups were useful in distinguishing JP8 exposure levels, job task-based categories should be considered in epidemiologic study designs to improve exposure classification. Finally

  10. Poison exposures in young Israeli military personnel: a National Poison Center Data analysis.

    Science.gov (United States)

    Lavon, Ophir; Bentur, Yedidia

    2017-06-01

    To characterize poison exposures in young Israeli military personnel as reported to the national poison center. Retrospective poison center chart review over a 14-year period. Cases included were Israeli soldiers aged 18-21 years, the compulsory military service age required by the Israeli law. 1770 records of poison exposures in young military personnel were identified. Most exposed individuals involved males (n = 1268, 71.6%). Main routes of exposure were ingestion (n = 854, 48.3%), inhalation (n = 328, 18.6%) and ocular (n = 211, 11.9%). Accidents or misuse (n = 712, 40.2%) were the most frequently reported circumstances, followed by suicide attempts (370, 20.9%), and bites and stings (161, 9.1%). More than half of the cases involved chemicals (n = 939, 53.1%); hydrocarbons, gases and corrosives were the main causative agents. Pharmaceuticals (mainly analgesics) were involved in 519 (29.3%) cases, venomous animals (mainly scorpions, centipedes, and snakes) in 79 (4.5%). Clinical manifestations were reported in 666 (37.6%) cases, mostly gastrointestinal, neurologic, and respiratory. The vast majority of cases (1634, 92.3%) were asymptomatic or mildly affected; no fatalities were recorded. In 831 (46.9%) cases the clinical toxicologist recommended referral to an emergency department; ambulatory observation was recommended in 563 (31.8%) cases, and hospitalization in 86 (4.9%). Our data show that poison exposures among young soldiers involve mainly males, accidents, misuse and suicides, oral route and chemicals; most exposures were asymptomatic or with mild severity. Repeated evaluations of poison center data pertaining to military personnel is advised for identifying trends in poison exposure and characteristics in this particular population.

  11. Personnel monitoring

    International Nuclear Information System (INIS)

    1965-01-01

    This film stresses the need for personnel monitoring in work areas where there is a hazard of exposure to radiation. It illustrates the use of personnel monitoring devices (specially the film dosimeter), the assessment of exposure to radiation and the detailed recording of the results on personnel filing cards

  12. Personnel monitoring

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1966-12-31

    This film stresses the need for personnel monitoring in work areas where there is a hazard of exposure to radiation. It illustrates the use of personnel monitoring devices (specially the film dosimeter), the assessment of exposure to radiation and the detailed recording of the results on personnel filing cards

  13. Audience, consequence, and journal selection in toxic-exposure epidemiology.

    Science.gov (United States)

    Rier, David A

    2004-10-01

    Even preliminary toxic-exposure epidemiology papers can spark "media scares" and questionable reactions amongst the public. Concerns for the social consequences of publication can lead epidemiologists--despite the advantages of visible publication--to choose a more obscure outlet for potentially sensitive studies. Interviews with 61 US toxic-exposure epidemiologists indicate that investigators generally sought visible journals to transmit their work to the widest relevant audience. Yet up to 36-46% of this sample sometimes have sought or would seek to keep their research from a public who, they feared, might misuse their results. Implications for the boundaries between science and society (including evidence of hidden scientific activism and "inert" public activism) are discussed, and six hypotheses for further research are proposed.

  14. Internal exposure monitoring of personnel of a nuclear power plant with pressurized-water reactors

    International Nuclear Information System (INIS)

    Krueger, F.W.; Poulheim, K.F.; Rueger, G.; Schreiter, W.D.

    1982-01-01

    In the GDR a programme for monitoring the internal radiation exposure of personnel has been established in the Bruno Leuschner Nuclear Power Plant, Greifswald, which allows one to estimate the effective dose equivalent in the way recommended by the ICRP. The measuring equipment used, and the methods of calibration and of evaluation of results are described. At present about 400 persons are monthly monitored with a thorax monitor in the nuclear power plant. If an investigation level - corresponding to an effective dose equivalent of 0.3mSv/month - is exceeded, a more exact measurement is made in the whole-body counter at the National Board for Nuclear Safety and Radiation Protection of the GDR. In addition, a selected group of 50 persons is measured twice yearly in the whole-body counter. The measurements show the high effectiveness of the protective measures against radionuclide intake by workers in the nuclear power plant, resulting in a contribution of less than 1% to the collective dose of the personnel. A correlation has been found between external and internal exposure indicating that, in general, there will be a higher intake only under conditions resulting also in higher external exposures. The highest individual values of internal exposure found are below 0.5mSv/month and thus within the range of the lower detection limit of dosimeter films used for monitoring the external exposure. (author)

  15. 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

  16. Reduction in radiation exposure to nursing personnel with the use of remote afterloading brachytherapy devices

    International Nuclear Information System (INIS)

    Grigsby, P.W.; Perez, C.A.; Eichling, J.; Purdy, J.; Slessinger, E.

    1991-01-01

    The radiation exposure to nursing personnel from patients with brachytherapy implants on a large brachytherapy service were reviewed. Exposure to nurses, as determined by TLD monitors, indicates a 7-fold reduction in exposure after the implementation of the use of remote afterloading devices. Quarterly TLD monitor data for six quarters prior to the use of remote afterloading devices demonstrate an average projected annual dose equivalent to the nurses of 152 and 154 mrem (1.5 mSv). After the implementation of the remote afterloading devices, the quarterly TLD monitor data indicate an average dose equivalent per nurse of 23 and 19 mrem (0.2 mSv). This is an 87% reduction in exposure to nurses with the use of these devices (p less than 0.01)

  17. Proteome Profiling Reveals Potential Toxicity and Detoxification Pathways Following Exposure of BEAS-2B Cells to Engineered Nanoparticle Titanium Dioxide

    Science.gov (United States)

    Identification of toxicity pathways linked to chemical -exposure is critical for a better understanding of biological effects of the exposure, toxic mechanisms, and for enhancement of the prediction of chemical toxicity and adverse health outcomes. To identify toxicity pathways a...

  18. Exposure to the atmospheric ionizing radiation environment: a study on Italian civilian aviation flight personnel

    International Nuclear Information System (INIS)

    De Angelis, G.; Caldora, M.; Santaquilani, M.; Scipione, R.; Verdecchia, A.

    2003-01-01

    A study of the effects of high-LET, low-dose and low-dose-rate ionizing radiation and associated risk analysis is underway. This study involves analyzing the atmospheric ionizing radiation exposure (including high-energy neutrons) and associated effects for members of civilian aviation flight personnel, in an attempt to better understand low-dose long-term radiation effects on human subjects. The study population includes all Italian civilian airline flight personnel, both cockpit and cabin crew members, whose work history records and actual flights (route, aircraft type, and date for each individual flight for each person where possible) are available. The dose calculations are performed along specific flight legs, taking into account the actual flight profiles for all different routes and the variations with time of solar and geomagnetic parameters. Dose values for each flight are applied to the flight history of study participants in order to estimate the individual annual and lifetime occupational radiation dose. An update of the study of the physical atmospheric ionizing radiation exposure is given here, in terms of environmental modeling, flight routes, radiation dose evaluation along different flight paths, and exposure matrix construction. The exposure analysis is still in progress, and the first results are expected soon

  19. Toxicity assessment of unintentional exposure to multiple chemicals

    International Nuclear Information System (INIS)

    Mumtaz, M.M.; Ruiz, P.; De Rosa, C.T.

    2007-01-01

    Typically exposure to environmental chemicals is unintentional, and often the exposure is to chemical mixtures, either simultaneously or sequentially. When exposure occurs, in public health practice, it is prudent to ascertain if thresholds for harmful health effects are exceeded, whether by individual chemicals or by chemicals in combination. Three alternative approaches are available for assessing the toxicity of chemical mixtures. Each approach, however, has shortcomings. As the procedures of each approach are described in this paper, at various steps research needs are identified. Recently, reliance has increased on computational toxicology methods for predicting toxicological effects when data are limited. Advances in molecular biology, identification of biomarkers, and availability of accurate and sensitive methods allow us to more precisely define the relationships between multiple chemical exposures and health effects, both qualitatively and quantitatively. Key research needs are best fulfilled through collaborative research. It is through such collaborations that resources are most effectively leveraged to further develop and apply toxicity assessment methods that advance public health practices in vulnerable communities

  20. Determination of personnel exposures in the lower energy ranges of X-ray by photographic dosimeter

    International Nuclear Information System (INIS)

    Ha, C.W.; Kim, J.R.; Suk, K.W.

    1986-01-01

    This paper described an improved technical method required for proper evaluation of personnel exposures by means of the photographic dosimeter developed by KAERI in lower gamma or X-ray energy regions, with which response of the dosimeter varies significantly. With calibration of the dosimeter in the energy range from 30 to 300 keV, the beam spectrum was carefully selected and specified it adequately. The absorber combinations and absorber thickness used to obtain the specified X-ray spectra from a constant potential X-ray machine were determined theoretically and also experimentally. A correlation between the density and exposure for the four separate energies, such as 49 keV eff , 154 keV eff 250 keV eff and 662 keV, is experimentally determined. As a result, it can be directly evaluated the exposure from the measured response of dosimeter. (Author)

  1. Evaluation of secondary exposure doses to transportation and medical personnel in the radiation emergency medicine

    International Nuclear Information System (INIS)

    Kato, Hideki; Suzuki, Shoichi; Koga, Sukehiko; Mukoyama, Takashi; Tomatsu, Hirotaka; Suzuki, Yusuke

    2009-01-01

    Radionuclide contamination is one of the accidents that might occur while carrying out a periodical inspection of nuclear power stations during normal reactor operation. When such an accident occurs, rescue and medical personnel, involved in transporting and treating affected workers run the risk of exposure to secondary radiation. In this study, the ambient dose equivalent rate at a certain distance from the surface of the human body contaminated with typical radioactive corrosion products was calculated. Further, the relationships among the adhesion area, contamination density, and secondary exposure dose were clarified. The secondary exposure dose and permissible working hours in a radiation emergency medicine were estimated by presenting these relationships in the form of a chart and by specifying the contamination levels. (author)

  2. Critical incident exposure in South African emergency services personnel: prevalence and associated mental health issues

    Science.gov (United States)

    Ward, C L; Lombard, C J; Gwebushe, N

    2006-01-01

    Objectives To assess critical incident exposure among prehospital emergency services personnel in the developing world context of South Africa; and to assess associated mental health consequences. Methods We recruited a representative sample from emergency services in the Western Cape Province, South Africa, to participate in this cross sectional epidemiological study. Questionnaires covered critical incident exposure, general psychopathology, risky alcohol use, symptoms of post‐traumatic stress disorder (PTSD), and psychological and physical aggression between co‐workers. Open ended questions addressed additional stressors. Results Critical incident exposure and rates of general psychopathology were higher than in studies in the developed world. Exposure to critical incidents was associated with general psychopathology, symptoms of PTSD, and with aggression between co‐workers, but not with alcohol use. Ambulance, fire, and sea rescue services had lower general psychopathology scores than traffic police. The sea rescue service also scored lower than traffic police on PTSD and psychological aggression. The defence force had higher rates of exposure to physical assault, and in ambulance services, younger staff were more vulnerable to assault. Women had higher rates of general psychopathology and of exposure to psychological aggression. Other stressors identified included death notification, working conditions, and organisational problems. Conclusions Service organisations should be alert to the possibility that their personnel are experiencing work ‐related mental health and behavioural problems, and should provide appropriate support. Attention should also be given to organisational issues that may add to the stress of incidents. Workplace programmes should support vulnerable groups, and address death notification and appropriate expression of anger. PMID:16498167

  3. All-cause mortality and radar exposure among french navy personnel: a 30 years cohort study

    International Nuclear Information System (INIS)

    Dabouis, V.; Arvers, P.; Debouzy, J.C.; Perrin, A.; Hours, M.

    2006-01-01

    To improve operational performance in a modern navy force, radiofrequency (RF) and microwaves emitting devices are widely used. It has been suggested that exposure to electromagnetic fields could be associated with greater health hazards and higher mortality. The all-cause mortality of 39488 militaries of the French navy forces was studied over the period 1975-2001 with a cohort epidemiological study. They served from 1975 until 1995. In a first step, the mortality of radar exposed militaries was compared to a control group formed by militaries who served during the same period in the same environment but without radar exposure. Administrative procedures for identifying militaries and their vital status were equivalent in the radar and the control groups. The age standardized mortality ratio in the radar navy personnel was 0.70 (95% CI: 0.54-0.90). In professional militaries, no difference in mortality ratio was found according to duration of estimated exposure. During a 30 years period of observation, we found no increase in all-cause mortality in the French navy personnel who were close to radar equipments

  4. Assessment of radiation exposure of personnel during clinical application of radioactive iridium

    Energy Technology Data Exchange (ETDEWEB)

    Dworakowski, M; Krystman-Mazgajska, E; Wysopolski, J [Instytut Onkologii, Warsaw (Poland); Centralne Lab. Ochrony Radiologicznej, Warsaw (Poland))

    1975-01-01

    The authors describe the results of measurements of doses and the evaluation of radiation exposure of the personnel of the Department of General Oncology working with application of radioactive iridium for interstitial and superficial treatment of neoplasma. The doses were measured by the photographic method simultaneously at six sites of the body: on the forehead, left side of the chest, 4th fingers of both hands, and on the left and right sides of the trunk at the level of gonads. The authors believe that introduction of iridium in place of radium will improve the conditions of work from the standpoint of protection against radioactivity.

  5. Budd-Chiari syndrome secondary to toxic pyrrolizidine alkaloid exposure.

    Science.gov (United States)

    Wu, Janet S W; Poon, W T; Ma, C K; Chen, M L; Pang, K S; Mak, Tony W L; Chan, H B

    2013-12-01

    In this report, we describe a case of pyrrolizidine alkaloid-related Budd-Chiari syndrome in Hong Kong. A 10-month-old boy presented with ascites, right pleural effusion, and hepatomegaly after consumption of herbal drinks for 3 months. His clinical (including imaging) features were compatible with Budd-Chiari syndrome. Budd-Chiari syndrome is a rare disease entity in paediatric patients. In our case, extensive workup performed to look for the underlying cause of Budd-Chiari syndrome was unrevealing, except for toxic pyrrolizidine alkaloid exposure in his herbal drinks.

  6. Triclosan: environmental exposure, toxicity and mechanisms of action.

    Science.gov (United States)

    Dann, Andrea B; Hontela, Alice

    2011-05-01

    Triclosan [5-chloro-2-(2,4-dichlorophenoxy)phenol; TCS] is a broad spectrum antibacterial agent used in personal care, veterinary, industrial and household products. TCS is commonly detected in aquatic ecosystems, as it is only partially removed during the wastewater treatment process. Sorption, biodegradation and photolytic degradation mitigate the availability of TCS to aquatic biota; however the by-products such as methyltriclosan and other chlorinated phenols may be more resistant to degradation and have higher toxicity than the parent compound. The continuous exposure of aquatic organisms to TCS, coupled with its bioaccumulation potential, have led to detectable levels of the antimicrobial in a number of aquatic species. TCS has been also detected in breast milk, urine and plasma, with levels of TCS in the blood correlating with consumer use patterns of the antimicrobial. Mammalian systemic toxicity studies indicate that TCS is neither acutely toxic, mutagenic, carcinogenic, nor a developmental toxicant. Recently, however, concern has been raised over TCS's potential for endocrine disruption, as the antimicrobial has been shown to disrupt thyroid hormone homeostasis and possibly the reproductive axis. Moreover, there is strong evidence that aquatic species such as algae, invertebrates and certain types of fish are much more sensitive to TCS than mammals. TCS is highly toxic to algae and exerts reproductive and developmental effects in some fish. The potential for endocrine disruption and antibiotic cross-resistance highlights the importance of the judicious use of TCS, whereby the use of TCS should be limited to applications where it has been shown to be effective. Copyright © 2011 John Wiley & Sons, Ltd.

  7. A review of the radiation exposure of transport personnel during the radioactive waste sea disposal operations from 1977-1982

    International Nuclear Information System (INIS)

    Mairs, J.H.

    1985-06-01

    The period of the review was chosen to give an account of the recent radiation exposures of transport personnel, which may serve as an indicator of possible future exposures associated with sea disposal operations. The annual radiation exposure of transport personnel has shown a significant reduction during the period of the review. These dose savings have been achieved despite a general increase in the quantities of wastes dumped. This is probably due to the improved shielding of packages and radiologically improved working procedures. If ocean disposal of solid or solidified radioactive waste was to be resumed the exposure of transport personnel might be expected to be comparable to the low doses received in the early 1980s. However, changes in packaging, handling procedures and frequency of movements would have major effects on radiation exposure. (author)

  8. Workplace standards for exposure to toxicants during pregnancy.

    Science.gov (United States)

    Till, Christine; Koren, Gideon; Rovet, Joanne F

    2008-01-01

    Many women of childbearing age are exposed to reproductive toxicants in the workplace. This article highlights the need for an evaluation of current occupational exposure guidelines for pregnant women working with hazardous agents that have the potential of being reproductive toxins. Limited information regarding reproductive risks associated with many chemicals in the workplace presents challenges in the establishment of standards that are 'safe' for vulnerable populations, such as the fetus. The management of these risks must take into consideration the limitations of available knowledge as well as individual risk factors that may amplify the likelihood of adverse outcomes. In 1981, Quebec adopted a policy that provides "precautionary leave" or reassignment of pregnant workers to other jobs if they are exposed to a factor suspected to compromise their health or that of their fetus during pregnancy. The advantages and disadvantages of this approach to managing reproductive hazards are discussed. The existence of a regulatory safety net at the level of the workplace for minimizing the impact of toxicant exposure on reproductive health outcomes is stressed. Management options that can be implemented early to provide added protection when a hazard cannot be reduced or eliminated are recommended.

  9. Beta Radiation exposure of medical personnel during vascular brachytherapy with Re-188

    International Nuclear Information System (INIS)

    Moka, D.; Baer, F.; Barth, I.; Rimpler, A.

    2002-01-01

    Intracoronary radiation is currently considered a promising breakthrough approach for preventing restenosis after angioplasty and stenting in patients with severe coronary artery disease. For the therapy of in-stent-restenosis vascular irradiation using balloon catheters filled with liquid radioisotopes provide excellent homogeneity due to the artery stenosis morphology. The radionuclide normally used is a Re-188 solutions (E β ,max=2,12 MeV). To achieve a sufficient dose in the stenosed artery wall (30 Gy in 0.5 mm wall depth) in a tolerable time-scale very high specific activities (>5-10 GBq/ml) of the isotope are necessary. During the preparation of the radioactive solution and the application at the patient very short distances between the source of the radiation and the skin of the doctors for cardiology / nuclear medicine are possible, especially when manipulations at the balloon catheter during the radiation are necessary. In addition, a severe risk of contamination exists. A further problem is that in hospitals often no or insufficient dosimeters for beta radiation are available. Occupational radiation exposure of the personnel was determined at the preparation of the Re-188 solution, the therapy itself and the waste management. The partial body exposure, i. e. the dose of the skin at the hands due to beta radiation, was determined with very sensitive thin-layer thermoluminescence dosimeters (TLD). During a preparation, intracoronary radiation and waste management of the Re-188-perrhenate solution using normal radiation shielding first measurements resulted din more than 500 mSv per working day at the fingertips. This extreme high radiation exposure of the personnel were mainly due to direct radiation by touching the evacuated balloon catheter (only residual radionuclides left). to reduced radiation we performed several additional radiation protection measures. The consequent use of plastic shielding of the source, the use of a semiautomatic preparation

  10. Personnel Dosimetry for Radiation Accidents. Proceedings of a Symposium on Personnel Dosimetry for Accidental High-Level Exposure to External and Internal Radiation

    International Nuclear Information System (INIS)

    1965-01-01

    Accidents involving the exposure of persons to high levels of radiation have been few in number and meticulous precautions are taken in an effort to maintain this good record. When, however, such an accident does occur, a timely estimate of the dose received can be of considerable help to the physician in deciding whether a particular person requires medical treatment, and in selecting the most appropriate treatment. Individual dosimetry provides the physical basis for relating the observed effects to those in other accident cases, to other human data, and to data from animal experiments, thus providing an important aid to rational treatment and to the accumulation of a meaningful body of knowledge on the subject. It is most important therefore that, where there is a possibility of receiving high-level exposure, methods of personnel dosimetry should be available that would provide the dosimetric information most useful to the physician. Provision of good personnel dosimetry for accidental high-level exposure is in many cases an essential part of emergency planning because the information provided may influence emergency and rescue operations, and can lead to improved accident preparedness. Accordingly, the International Atomic Energy Agency and the World Health Organization jointly organized the Symposium on Personnel Dosimetry for Accidental High-Level Exposure to External and Internal Radiation for the discussion of such methods and for a critical review of the procedures adopted in some of the radiation accidents that have already occurred. The meeting was attended by 179 participants from 34 countries and from five other international organizations. The papers presented and the ensuing discussions are published in these Proceedings. It is hoped that the Proceedings will be of help to those concerned with the organization and development of wide-range personnel monitoring systems, and with the interpretation of the results provided

  11. Assessment of exposure-response functions for rocket-emission toxicants

    National Research Council Canada - National Science Library

    Subcommittee on Rocket-Emission Toxicants, National Research Council

    ... aborted launch that results in a rocket being destroyed near the ground. Assessment of Exposure-Response Functions for Rocket-Emmission Toxicants evaluates the model and the data used for three rocket emission toxicants...

  12. Risk assessments for exposure of deployed military personnel to insecticides and personal protective measures used for disease-vector management.

    Science.gov (United States)

    Macedo, Paula A; Peterson, Robert K D; Davis, Ryan S

    2007-10-01

    Infectious diseases are problematic for deployed military forces throughout the world, and, historically, more military service days have been lost to insect-vectored diseases than to combat. Because of the limitations in efficacy and availability of both vaccines and therapeutic drugs, vector management often is the best tool that military personnel have against most vector-borne pathogens. However, the use of insecticides may raise concerns about the safety of their effects on the health of the military personnel exposed to them. Therefore, our objective was to use risk assessment methodologies to evaluate health risks to deployed U.S. military personnel from vector management tactics. Our conservative tier-1, quantitative risk assessment focused on acute, subchronic, and chronic exposures and cancer risks to military personnel after insecticide application and use of personal protective measures in different scenarios. Exposures were estimated for every scenario, chemical, and pathway. Acute, subchronic, and chronic risks were assessed using a margin of exposure (MOE) approach. Our MOE was the ratio of a no-observed-adverse-effect level (NOAEL) to an estimated exposure. MOEs were greater than the levels of concern (LOCs) for all surface residual and indoor space spraying exposures, except acute dermal exposure to lambda-cyhalothrin. MOEs were greater than the LOCs for all chemicals in the truck-mounted ultra-low-volume (ULV) exposure scenario. The aggregate cancer risk for permethrin exceeded 1 x 10(-6), but more realistic exposure refinements would reduce the cancer risk below that value. Overall, results indicate that health risks from exposures to insecticides and personal protective measures used by military personnel are low.

  13. Tetrabromobisphenol A – Toxicity, environmental and occupational exposures

    Directory of Open Access Journals (Sweden)

    Monika Jarosiewicz

    2017-02-01

    Full Text Available Brominated flame retardants (BFR, including tetrabromobisphenol A (TBBPA represents 25% of the global market of flame retardants. Among them, TBBPA is used on the largest scale (approx. 60% because of its firebreak properties and widespread occurrence in every day products such as furniture, upholstery, adhesives and electronic equipment. A broad application of TBBPA can contribute to environmental pollution. Tetrabromobisphenol A has been determined in soil, water, river sediments and the atmosphere. Tetrabromobisphenol A is characterized by a high value of coefficient n-octanol/water (log P = 4.5, low acidity, and it may exist in undissociated or dissociated form. Due to the high hydrophobicity, TBBPA may accumulate in living organisms, including humans at different food chain levels. The occurrence of TBBPA in humans, e.g., in blood, fat tissue and mother milk, has been reported. Tetrabromobisphenol A is classified as hazard statements (H H400/H410, which means that it is toxic to aquatic biota, causing long-term changes in these organisms. Up to now, only a few studies have been conducted to assess potential toxicity of high doses of TBBPA to mammals. Although many people are occupationally exposed to TBBPA during production or processing of this substance in their workplaces, there are only a few studies that have assessed the real hazard associated with TBPPA exposure. The aim of the study was to discuss the latest literature (mainly from the years 2010–2016 referring to the presence of TBBPA in the environment and its effects to living organisms. Data concerning occupational exposure to TBBPA were also presented. Med Pr 2017;68(1:121–134

  14. Radiation exposure of holding personnel involved in veterinary X-ray diagnosis

    International Nuclear Information System (INIS)

    Rothe, W.

    1977-01-01

    An account is given of radiation protection in the context of X-ray examination of small and big animals on the premises of seven reviewed veterinary centres. Also reported are the dosimetric results obtained from holding personnel involved in X-ray diagnosis of 319 big and 4,047 small animals. Infringement of valid regulations was quite often observed, in that animals are held in position in an inadequate way and by unauthorised persons. The measured results, however, have shown that the radiation exposure of vocationally exposed persons can be kept far below the maximum permissible equivalent doses, provided that all applicable rules of radiation protection are observed by those on duty. (author)

  15. Occupational radiation exposure in Austria - results of personnel monitoring using thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Duftschmid, K.E.

    1979-01-01

    The Institut fuer Strahlenschutz, Seibersdorf, can look back on more than two years of experience with the automated TLD personnel monitoring system for routine control and dose record keeping of currently about 10.000 persons per month. For more than 100.000 entries on monthly received doses have been stored so far in the Master File of the Institute's computer centre. This paper presents a survey of the statistical dose distribution in the various sectors of employment such as industry, research establishments, medical establishments and nuclear facilities, including data on the mean annual doses and the collective doses for the various sectors; information is also given on the number of cases where a dose has been in excess of the set level, and on the measured data. The data stored in the dose record keeping system allow a detailed assessment to be made of the occupational radiation exposure in Austria. (orig.) [de

  16. Radiation exposure control of nuclear power plant personnel in the Federal Republic of Germany

    International Nuclear Information System (INIS)

    Mehl, J.

    1980-01-01

    The analysis of exposure records of all persons engaged in radiation work at nuclear power plants of the Federal Republic of Germany has shown that annual collective doses increase rapidly with time. The annual gross electrical energy generated from nuclear power also increases rapidly with time, corresponding to about 11% of the total gross electrical energy produced in 1977/78. Therefore, it is obvious that there is an increase of both the risk and the benefit from nuclear power production. Whether in the course of time the situation develops more towards the risk or the benefit side is learned from the history of the annual ratio of the collective dose per gross electrical energy generated. This ratio shows a significant decrease since 1972. The decrease is due to the experience gained from operation of the first-generation plants, which led to several administrative measures aimed at an improved control of the collective doses of power plant personnel in the Federal Republic of Germany. The administrative measures include, among others, the introduction of the following requirements: (a) Everyone who applies for a nuclear power plant construction licence has to provide evidence that, in the design of the plant, full use is made of the experience gained from plants in operation with respect to reduction of collective doses of the power plant personnel. (b) Everyone who engages his employees on radiation work within operations for which an operation licence is required, but which is held by others, requires a special 'contractor licence'. (c) Every person engaged in radiation work on the basis of a contractor licence must carry a special exposure record book which is registered by the competent national authority. (author)

  17. Advances in exposure and toxicity assessment of particulate matter: An overview of presentations at the 2009 Toxicology and Risk Assessment Conference

    International Nuclear Information System (INIS)

    Gunasekar, Palur G.; Stanek, Lindsay W.

    2011-01-01

    The 2009 Toxicology and Risk Assessment Conference (TRAC) session on 'Advances in Exposure and Toxicity Assessment of Particulate Matter' was held in April 2009 in West Chester, OH. The goal of this session was to bring together toxicology, geology and risk assessment experts from the Department of Defense and academia to examine issues in exposure assessment and report on recent epidemiological findings of health effects associated with particulate matter (PM) exposure. Important aspects of PM exposure research are to detect and monitor low levels of PM with various chemical compositions and to assess the health risks associated with these exposures. As part of the overall theme, some presenters discussed collection methods for sand and dust from Iraqi and Afghanistan regions, health issues among deployed personnel, and future directions for risk assessment research among these populations. The remaining speakers focused on the toxicity of ultrafine PM and the characterization of aerosols generated during ballistic impacts of tungsten heavy alloys.

  18. Review of the toxicologic and radiologic risks to military personnel from exposure to depleted uranium during and after combat

    National Research Council Canada - National Science Library

    National Academies Press (U.S.); National Research Council (U.S.). Board on Environmental Studies and Toxicology; National Research Council (U.S.) Committee on Toxicologic and Radiologic Effects from Exposure to Depleted Uranium During and After Combat

    2008-01-01

    .... Depleted uranium is a toxic heavy metal and is weakly radioactive. Concerns have been raised about the adverse health effects from exposure to depleted uranium that is aerosolized during combat...

  19. Comprehensive evaluation of occupational radiation exposure to intraoperative and perioperative personnel from 18F-FDG radioguided surgical procedures

    International Nuclear Information System (INIS)

    Povoski, Stephen P.; Martin, Edward W.; Sarikaya, Ismet; Hall, Nathan C.; Knopp, Michael V.; White, William C.; Marsh, Steven G.; Hinkle, George H.

    2008-01-01

    The purpose of the current study was to comprehensively evaluate occupational radiation exposure to all intraoperative and perioperative personnel involved in radioguided surgical procedures utilizing 18 F-fluorodeoxyglucose ( 18 F-FDG). Radiation exposure to surgeon, anesthetist, scrub technologist, circulating nurse, preoperative nurse, and postoperative nurse, using aluminum oxide dosimeters read by optically stimulated luminescence technology, was evaluated during ten actual radioguided surgical procedures involving administration of 18 F-FDG. Mean patient dosage of 18 F-FDG was 699 ± 181 MBq (range 451-984). Mean time from 18 F-FDG injection to initial exposure of personnel to the patient was shortest for the preoperative nurse (75 ± 63 min, range 0-182) followed by the circulating nurse, anesthetist, scrub technologist, surgeon, and postoperative nurse. Mean total time of exposure of the personnel to the patient was longest for the anesthetist (250 ± 128 min, range 69-492) followed by the circulating nurse, scrub technologist, surgeon, postoperative nurse, and preoperative nurse. Largest deep dose equivalent per case was received by the surgeon (164 ± 135 μSv, range 10-580) followed by the anesthetist, scrub technologist, postoperative nurse, circulating nurse, and preoperative nurse. Largest deep dose equivalent per hour of exposure was received by the preoperative nurse (83 ± 134 μSv/h, range 0-400) followed by the surgeon, anesthetist, postoperative nurse, scrub technologist, and circulating nurse. On a per case basis, occupational radiation exposure to intraoperative and perioperative personnel involved in 18 F-FDG radioguided surgical procedures is relatively small. Development of guidelines for monitoring occupational radiation exposure in 18 F-FDG cases will provide reassurance and afford a safe work environment for such personnel. (orig.)

  20. Radiation exposure to personnel involved in bone scans for horses with technetium 99m-diphosphonat

    International Nuclear Information System (INIS)

    Sommerfeld, Theresa Christine

    2016-01-01

    Key objective of this study has been the evaluation of radiation exposure of veterinarian personnel wearing dosimeters which were involved in equine scintigraphy. A survey, which was developed in parallel to this study, showed that personnel in equine horse clinics have often knowledge gaps about scintigraphy and the related radiation doses. The survey showed skepticism of the involved personnel towards the methods of bone scintigraphy as the impacts of expositions are barely known in common. The scintigraphic investigations and measurements were done at the horse clinic (department of surgery) in Giessen and were part of the routinely bone scanning of horses. A total of 33 bone scans were taken, covering either full- or half-body scintigraphies. Additional 10 bone scans covered measurements with and without the protection of a 0,5 mm lead-shield. The activity of involved personnel was monitored at four different positions: MP1 was associated with the position of the person preparing the radiopharmaceutical for injection, MP2 with the position at holding the horse during the bone scan, MP3 with the position at holding the horse's legs and to make sure that the horse was standing in the right position, MP4 with the position for the camera operator. Some more dose measurements were made from the horse body (MP5 and MP6) as well as in the control area (MP7). In order to analyze the patient's constitution, additional data like weight, size, body extent and length of the torso were additionally captured. The body data were collected to investigate exposure differences of rather big and heavy or small and thin horses. These data and the dosimeter at the horse body (MP5) enabled the correlation analysis between the horse body composition and the received dose rate of the personnel (MP2). MP1 received a mean dose of 11 μSv and a dose rate of 123 μSv/h, MP2 received 31 μSv for a whole-body and 23 μSv for a half-body bone scan. The dose rate of MP2 was 22 μSv/h. MP3 was

  1. Health physics experiences in achieving ALARA exposures to plant personnel at NAPS

    International Nuclear Information System (INIS)

    Ramakrishna, V.; Lal Chand

    2000-01-01

    Unit 1 of NAPS achieved first criticality on 12.3.1989 and Unit 2 achieved on 24.10.1991. Till the end of Feb-2000 these units have completed 1890 and 1811 full power days respectively. The performance of NAPS was expected to be better than the earlier Indian reactors in respect of safe production as well as cumulative radiation exposures. This is because of the major design improvements like: fully double containment system, elimination of 41 Ar by introducing light water in calandria vault, reduction of core based fuel failure rate, separation of high radiation equipment to no occupancy areas during normal operation, a separate purification building for the purification of both moderator and PHT systems, a better layout of equipment and plant areas, elimination of unnecessary equipment in various systems besides ensuring the reliability of equipment for safe operation, selection of materials with low corrosion and activation characteristics etc. In this paper, the operational health physics experiences at NAPS to achieve ALARA exposures to plant personnel are described briefly. (author)

  2. A re-circulated toxicity exposure chamber to evaluate hydrocarbon dispersions

    International Nuclear Information System (INIS)

    Fuller, C.B.; Bonner, J.S.; Bujnoch, J.D.; Ussery, S.F.; Arrambide, G.; Sterling, M.C.

    2002-01-01

    Traditional toxicology methods are not suitable for evaluating chemically dispersed oil which exists mostly as a colloidal suspension and as dissolved fractions. A new toxicity exposure chamber was designed with separate chambers for scaled mixing and organism exposure. The design of the chamber incorporates continuous recirculation between the mixing and exposure chamber and an upward flow in the exposure chamber. The toxicity exposure system incorporates scalable and quantitative mixing inputs with real time particle size analysis and traditional petrochemistry methods to characterize the exposure regime. Changes in dispersion were successfully translated to the organism exposure regime. The study determined the petroleum toxicity with a juvenile marine test species. Low control mortality demonstrated the usefulness of the method for testing toxicity of colloidal oil suspensions. 20 refs., 1 tab., 4 figs

  3. PRD3000: A novel Personnel Radiation Detector with Radiation Exposure Monitoring

    International Nuclear Information System (INIS)

    Fallu-Labruyere, A.; Micou, C.; Schulcz, F.; Fellinger, J.

    2015-01-01

    PRD3000 TM is a novel Personal Radiation Detector (PRD) with personnel radiation dose exposure monitoring. It is intended for First Responders, Law Enforcement, Customs Inspectors protecting critical infrastructures for detecting unexpected radioactive sources, who also need real time Hp(10) dose equivalent information. Traditional PRD devices use scintillator materials instrumented through either a photomultiplier tube or a photodiode photodetector. While the former is bulky and sensitive to magnetic fields, the latter has to compromise radiation sensitivity and energy threshold given its current noise per unit of photo-detection surface. Recently, solid state photodetectors (SiPM), based on arrays of Geiger operated diodes, have emerged as a scalable digital photodetector for photon counting. Their strong breakdown voltage temperature dependence (on the order of tens of milli-volts per K) has however limited their use for portable instruments where strong temperature gradients can be experienced, and limited power is available to temperature stabilize. The PRD3000 is based on the industry standard DMC3000 active dosimeter that complies with IEC 61526 Ed. 3 and ANSI 42.20 for direct reading personal dose equivalent meters and active personnel radiation monitors. An extension module is based on a CsI(Tl) scintillator readout by a temperature compensated SiPM. Preliminary nuclear tests combined with a measured continuous operation in excess of 240 hours from a single AAA battery cell indicate that the PRD3000 complies with the IEC 62401 Ed.2 and ANSI 42.32 without sacrificing battery life time. We present a summary of the device test results, starting with performance stability over a temperature range of - 20 deg. C to 50 deg. C, false alarm rates and dynamic response time. (authors)

  4. PRD3000: A novel Personnel Radiation Detector with Radiation Exposure Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Fallu-Labruyere, A.; Micou, C.; Schulcz, F.; Fellinger, J. [Mirion Technologies - MGPI SA (France)

    2015-07-01

    PRD3000{sup TM} is a novel Personal Radiation Detector (PRD) with personnel radiation dose exposure monitoring. It is intended for First Responders, Law Enforcement, Customs Inspectors protecting critical infrastructures for detecting unexpected radioactive sources, who also need real time Hp(10) dose equivalent information. Traditional PRD devices use scintillator materials instrumented through either a photomultiplier tube or a photodiode photodetector. While the former is bulky and sensitive to magnetic fields, the latter has to compromise radiation sensitivity and energy threshold given its current noise per unit of photo-detection surface. Recently, solid state photodetectors (SiPM), based on arrays of Geiger operated diodes, have emerged as a scalable digital photodetector for photon counting. Their strong breakdown voltage temperature dependence (on the order of tens of milli-volts per K) has however limited their use for portable instruments where strong temperature gradients can be experienced, and limited power is available to temperature stabilize. The PRD3000 is based on the industry standard DMC3000 active dosimeter that complies with IEC 61526 Ed. 3 and ANSI 42.20 for direct reading personal dose equivalent meters and active personnel radiation monitors. An extension module is based on a CsI(Tl) scintillator readout by a temperature compensated SiPM. Preliminary nuclear tests combined with a measured continuous operation in excess of 240 hours from a single AAA battery cell indicate that the PRD3000 complies with the IEC 62401 Ed.2 and ANSI 42.32 without sacrificing battery life time. We present a summary of the device test results, starting with performance stability over a temperature range of - 20 deg. C to 50 deg. C, false alarm rates and dynamic response time. (authors)

  5. Metabolic response to low-level toxicant exposure in a novel renal tubule epithelial cell system

    NARCIS (Netherlands)

    Ellis, James Keith; Athersuch, Toby James; Cavill, Rachel; Radford, Robert; Slattery, Craig; Jennings, Paul; McMorrow, Tara; Ryan, Michael P; Ebbels, Timothy Mark David; Keun, Hector Charles

    Toxicity testing is vital to protect human health from exposure to toxic chemicals in the environment. Furthermore, combining novel cellular models with molecular profiling technologies, such as metabolomics can add new insight into the molecular basis of toxicity and provide a rich source of

  6. Evaluation of radiation exposures to personnel during maintenance operations and fuel recharging at NPP with the WWER-440 reactor

    International Nuclear Information System (INIS)

    Beskrestnov, N.V.; Vasil'ev, Eh.S.; Kozlov, V.F.; Odinokov, Yu.Yu.; Romanov, V.P.; Tsypin, S.G.

    1983-01-01

    A unified data acquisition and analysis system is presented. The system is intended to assess radiation exposures to personnel and perform radiation monitoring during periodic maintenance operations sna fuel recharging at NPPs with WWER-440 reactors. The basic principles of developing this system, patterns of danita collection are considered, points of radiation motoring chosen with account of the NPP operating experience are pointed out

  7. Radiation exposure of patients and personnel in pediatric radiology. Strahlenexposition von Patienten und Personal in der Paediatrischen Radiologie

    Energy Technology Data Exchange (ETDEWEB)

    Wallbaum, F

    1980-01-01

    Skin, gonadal and eye lens exposure of children up to the age of 14, X-ray personnel and accompanying adults (mother and nurses) in gastroenterological and urological examinations are investigated. Particular interest is taken in combined examinations, i.e. radiography combined with radioscopy, as these are strongly dependent on the examiner.

  8. Radiation exposure of patients and personnel in pediatric radiology. Strahlenexposition von Patienten und Personal in der Paediatrischen Radiologie

    Energy Technology Data Exchange (ETDEWEB)

    Wallbaum, F

    1980-04-23

    Skin, gonadal and eye lens exposure of children up to the age of 14, X-ray personnel and accompanying adults (mother and nurses) in gastroenterological and urological examinations are investigated. Particular interest is taken in combined examinations, i.e. radiography combined with radioscopy, as these are strongly dependent on the examiner.

  9. Evaluation of effects of long term exposure on lethal toxicity with mammals

    International Nuclear Information System (INIS)

    Verma, Vibha; Yu, Qiming J.; Connell, Des W.

    2014-01-01

    The relationship between exposure time (LT 50 ) and lethal exposure concentration (LC 50 ) has been evaluated over relatively long exposure times using a novel parameter, Normal Life Expectancy (NLT), as a long term toxicity point. The model equation, ln(LT 50 ) = aLC 50 ν + b, where a, b and ν are constants, was evaluated by plotting lnLT 50 against LC 50 using available toxicity data based on inhalation exposure from 7 species of mammals. With each specific toxicant a single consistent relationship was observed for all mammals with ν always <1. Use of NLT as a long term toxicity point provided a valuable limiting point for long exposure times. With organic compounds, the Kow can be used to calculate the model constants a and v where these are unknown. The model can be used to characterise toxicity to specific mammals and then be extended to estimate toxicity at any exposure time with other mammals. -- Highlights: • Model introduces a new parameter, normal life expectancy, to explain changes in toxicity with time. • Model is innovatory as it can be used to calculate toxicity at any, particularly long exposure times. • Toxicity is influenced by normal life expectancy of the organism particularly longer exposure times. • The model was applicable to all the mammals (7 species) evaluated. • The model can be used to predict toxicity at different exposure times with untested mammals species. -- The RLE model provides a mathematical description of the change in toxicity over time for a particular chemical. This represents a major advance on the use of Haber's Rule in toxicology

  10. Study on cognitive behavioural coping of intervention and rescue personnel in toxic / flammable / explosive environments

    Directory of Open Access Journals (Sweden)

    Kovacs Izabella

    2017-01-01

    Full Text Available In any given field, the psychological examination represents a prerequisite for ensuring that the work process is properly and appropriately directed towards increasing its efficiency. An important aspect of the psychological examination is to identify risk and protective factors associated with developing and maintaining emotional and behavioural problems. Special conditions resulting from emergency situations are likely to lead to physical and emotional tensions. In some intervention and rescue personnel these are accompanied by mobilization of internal resource, while in others they can generate inadequacy phenomena and symptoms of mental distress. From this perspective, stress is regarded as a result of the marked disparity between environmental requirements and the individual’s response possibilities. To highlight both cognitive and behavioural coping strategies most often used by rescuers trained in NRDI INSEMEX we used two instruments, namely Strategic Approach to Coping Scale SACS and Cognitive Emotion Regulation Questionnaire CERQ. This paper displays the results of the project no. PN 16 43 01 12, study conducted through Nucleu program, implemented with the support of NASR.

  11. Toxicity assessment due to sub-chronic exposure to individual and mixtures of four toxic heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Cobbina, Samuel J.; Chen, Yao [School of the Environment, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013, Jiangsu (China); Zhou, Zhaoxiang; Wu, Xueshan; Zhao, Ting [School of Chemistry and Chemical Engineering, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013 (China); Zhang, Zhen [School of the Environment, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013, Jiangsu (China); Feng, Weiwei; Wang, Wei [School of Food and Biological Engineering, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013, Jiangsu (China); Li, Qian [School of Pharmacy, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013, Jiangsu (China); Wu, Xiangyang, E-mail: wuxy@ujs.edu.cn [School of the Environment, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013, Jiangsu (China); Yang, Liuqing, E-mail: yangliuqing@ujs.edu.cn [School of Chemistry and Chemical Engineering, Jiangsu University, Xuefu Rd. 301, Zhenjiang 212013 (China)

    2015-08-30

    Highlights: • Low dose single and mixtures of toxic metals had adverse effect on mice. • Metal mixtures exhibited higher toxicities compared to individual metals. • Mixtures of low dose Pb + Hg + Cd induced neuronal degeneration in brain of mice. • Exposure to Pb + Hg + As + Cd showed renal tubular necrosis in kidney. - Abstract: Humans are exposed to a cocktail of heavy metal toxicants in the environment. Though heavy metals are deleterious, there is a paucity of information on toxicity of low dose mixtures. In this study, lead (Pb) (0.01 mg/L), mercury (Hg) (0.001 mg/L), cadmium (Cd) (0.005 mg/L) and arsenic (As) (0.01 mg/L) were administered individually and as mixtures to 10 groups of 40 three-week old mice (20 males and 20 females), for 120 days. The study established that low dose exposures induced toxicity to the brain, liver, and kidney of mice. Metal mixtures showed higher toxicities compared to individual metals, as exposure to low dose Pb + Hg + Cd reduced brain weight and induced structural lesions, such as neuronal degeneration in 30-days. Pb + Hg + Cd and Pb + Hg + As + Cd exposure induced hepatocellular injury to mice evidenced by decreased antioxidant activities with marginal increases in MDA. These were accentuated by increases in ALT, AST and ALP. Interactions in metal mixtures were basically synergistic in nature and exposure to Pb + Hg + As + Cd induced renal tubular necrosis in kidneys of mice. This study underlines the importance of elucidating the toxicity of low dose metal mixtures so as to protect public health.

  12. "Making Do" Decisions: How Home Healthcare Personnel Manage Their Exposure to Home Hazards.

    Science.gov (United States)

    Wills, Celia E; Polivka, Barbara J; Darragh, Amy; Lavender, Steven; Sommerich, Carolyn; Stredney, Donald

    2016-04-01

    This study describes the decision-making processes home healthcare personnel (HHP) use to manage their personal health and safety when managing hazards in client homes. A professionally diverse national sample of 68 HHP participated in individual semi-structured interviews and focus group discussions, and described their decision making and strategies for hazard management in their work environments. HHP described 353 hazard management dilemmas within 394 specifically identified hazards, which were clustered within three broader categories: electrical/fire, slip/trip/lift, and environmental exposures. HHP described multiple types of "making do" decisions for hazard management solutions in which perceived and actual resource limitations constrained response options. A majority of hazard management decisions in the broader hazards categories (72.5%, 68.5%, and 63.5%, respectively) were classifiable as less than optimal. These findings stress the need for more support of HHPs, including comprehensive training, to improve HHP decision making and hazard management strategies, especially in context of resource constraints. © The Author(s) 2015.

  13. The state of radioactive waste management and personnel radiation exposure in commercial nuclear power plants in fiscal 1981

    International Nuclear Information System (INIS)

    1982-01-01

    Radioactive waste management: The owners of commercial nuclear power plants are obligated to control the release of gaseous and liquid radioactive wastes below the objective release levels, and to store solid wastes in containers on the site. As for the former, the released (radioactive) quantity in fiscal 1981 (from April, 1981, to March, 1982,) together with the objective levels are given for respective nuclear power stations; and as for the latter, the stored quantity and also the cumulative quantity up to the year are given. Radiation exposure: The owners of commercial nuclear power plants are obligated to control the personnel exposure below the permissible level. The personnel exposure dose in fiscal 1981 is given for respective nuclear power station. (Mori, K.)

  14. Tracking pyrethroid toxicity in surface water samples: Exposure dynamics and toxicity identification tools for laboratory tests with Hyalella azteca (Amphipoda).

    Science.gov (United States)

    Deanovic, Linda A; Stillway, Marie; Hammock, Bruce G; Fong, Stephanie; Werner, Inge

    2018-02-01

    Pyrethroid insecticides are commonly used in pest control and are present at toxic concentrations in surface waters of agricultural and urban areas worldwide. Monitoring is challenging as a result of their high hydrophobicity and low toxicity thresholds, which often fall below the analytical methods detection limits (MDLs). Standard daphnid bioassays used in surface water monitoring are not sensitive enough to protect more susceptible invertebrate species such as the amphipod Hyalella azteca and chemical loss during toxicity testing is of concern. In the present study, we quantified toxicity loss during storage and testing, using both natural and synthetic water, and presented a tool to enhance toxic signal strength for improved sensitivity of H. azteca toxicity tests. The average half-life during storage in low-density polyethylene (LDPE) cubitainers (Fisher Scientific) at 4 °C of 5 pyrethroids (permethrin, bifenthrin, lambda-cyhalothrin, cyfluthrin, and esfenvalerate) and one organophosphate (chlorpyrifos; used as reference) was 1.4 d, and piperonyl butoxide (PBO) proved an effective tool to potentiate toxicity. We conclude that toxicity tests on ambient water samples containing these hydrophobic insecticides are likely to underestimate toxicity present in the field, and mimic short pulse rather than continuous exposures. Where these chemicals are of concern, the addition of PBO during testing can yield valuable information on their presence or absence. Environ Toxicol Chem 2018;37:462-472. © 2017 SETAC. © 2017 SETAC.

  15. Exposure to suicide is associated with increased risk for suicidal thoughts and behaviors among National Guard military personnel.

    Science.gov (United States)

    Bryan, Craig J; Cerel, Julie; Bryan, AnnaBelle O

    2017-08-01

    Research suggests that individuals who know someone who died by suicide are at increased risk for posttraumatic stress disorder (PTSD), depression, and recent suicidal thoughts. Studies have not yet investigated the association of suicide exposure with suicide attempts, however, especially among high-risk subgroups of military personnel such as the National Guard. An anonymous online survey was completed by 971 military personnel assigned to the National Guard in Utah and Idaho. Weighted analyses were conducted to ensure demographic matching to the full population. Univariate and multivariate logistic regression was used to test the association of suicide exposure with psychiatric condition, suicide ideation, and suicide attempts. 65.4% of National Guard personnel reported knowing someone who had died by suicide. On average, participants knew 3.0 (SD=2.0) suicide decedents. Total number of known suicide decedents was associated with significantly increased risk for PTSD (OR=1.18, p=.008), depression (OR=1.19, p=.003), and suicide ideation (OR=2.48, p<.001), but not suicide attempt (OR=1.34, p=.472). Perceived closeness to the suicide decedent was associated with significantly increased risk for PTSD (OR=1.54, p<.001), depression (OR=1.36, p=.031), suicide ideation (OR=1.24, p=.039), and suicide attempt (OR=1.69, p=.026). The majority of participants who experienced suicidal thoughts and attempts after the suicide exposure had a previous history of suicide ideation. Suicide exposure is common among National Guard personnel, and is associated with increased risk for PTSD, depression, and suicidal thoughts and behaviors. Risk is highest for those personnel who know multiple suicide decedents and were closer to the suicide decedent. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Radiation exposure to nuclear medicine personnel handling positron emitters from 68Ge/68Ga generator

    International Nuclear Information System (INIS)

    Dwivedi, Durgesh Kumar; Snehlata; Kumar, Rakesh; Naswa, Niraj; Sharma, Punit; Malhotra, Arun; Bandopadhayaya, Guru Pad; Bal, Chandrashekhar; Dwivedi, Alok Kumar; Lochab, Satya Pal; Pant, Gauri Shankar

    2011-01-01

    To measure the radiation exposure to nuclear medicine personnel during synthesis and injection to the patients of 68 Ga 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid (DOTA)-1-Nal -octreotide (NOC)- (DOTA-NOC) using ring thermoluminescence dosimeters (TLDs). Synthesis of 68 Ga DOTA-NOC was done on a semi-automated system. Finger doses were measured during synthesis and injection of 68 Ga DOTA-NOC. The occupational workers wore TLDs at the base of ring finger of both hands. The finger doses of two radio chemists were measured during synthesis of 68 Ga DOTA-NOC while that of a physician during its injection to the patients. Duration of the study was eight months and a total of 20 samples were prepared. During synthesis, the mean dose to base of left ring finger was 3.02 ± 1.01 mSv and to base of right ring finger was 1.96 ±0.86 mSv. Mean dose to base of left ring finger was 1.26 ± 0.35 mSv while that to base of right ring finger was 1.03 ± 0.13 mSv during injection. The mean dose was observed to be higher during synthesis than injection. However, the difference was not significant (P = 0.27 and P = 0.18, respectively). Overall mean finger dose of left hand was 2.43 ±1.21 mSv, whereas for the right hand the same was 1.65±0.82 mSv. Finger doses to radio chemists during semi-automated synthesis of 68 Ga DOTA-NOC and that to the physician involved in injection of 68 Ga DOTA-NOC were found to be within permissible limits. Ring dosimeters must be worn for the safety of the nuclear medicine personnel involved in synthesis and injection of 68 Ga DOTA-NOC. (author)

  17. Integrated toxic evaluation of sulfamethazine on zebrafish: Including two lifespan stages (embryo-larval and adult) and three exposure periods (exposure, post-exposure and re-exposure).

    Science.gov (United States)

    Yan, Zhengyu; Yang, Qiulian; Jiang, Weili; Lu, Jilai; Xiang, Zhongrun; Guo, Ruixin; Chen, Jianqiu

    2018-03-01

    Persistence of antibiotics in aquatic environment may pose a risk to the non-target aquatic organisms. This study provided an integrated evaluation to analyze the toxic stress of sulfamethazine (SMZ) on zebrafish in two lifespan stages (embryo-larval and adult) and three exposure periods (exposure, post-exposure and re-exposure). Zebrafish embryos and adult zebrafish were exposed to SMZ at 0.2, 20 and 2000 μg/L, respectively. The results showed that SMZ at any given concentration inhibited the hatching of embryos at 58-96 hpf (hours post-fertilization). Our result also indicated that two major kinds of the malformation, which was induced by the antibiotic, were edema and spinal curvature. Additionally, the antibiotic stimulated the heartbeat while reduced the body length of the embryo at 72 hpf. Superoxide dismutase (SOD) activities and malondialdehyde (MDA) contents significantly increased at 120 hpf when the embryos were exposed to the lowest concentration (0.2 μg/L) of the antibiotic. On the other hand, the antibiotic induced SOD activities and MDA contents in adult zebrafish in the exposure and re-exposure periods. The MDA contents could recover while SOD activities still increased in 2 d after the exposure. Both SOD activities and MDA contents could recover in 7 d after the exposure. Levels of SOD and MDA in the re-exposure were higher than those in the first exposure. Our results suggested that SMZ had toxic effects on both embryos and adult zebrafish, and provided an integrated evaluation of the toxic effects of SMZ on zebrafish at a new perspective. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Evaluation of effects of long term exposure on lethal toxicity with mammals.

    Science.gov (United States)

    Verma, Vibha; Yu, Qiming J; Connell, Des W

    2014-02-01

    The relationship between exposure time (LT50) and lethal exposure concentration (LC50) has been evaluated over relatively long exposure times using a novel parameter, Normal Life Expectancy (NLT), as a long term toxicity point. The model equation, ln(LT50) = aLC50(ν) + b, where a, b and ν are constants, was evaluated by plotting lnLT50 against LC50 using available toxicity data based on inhalation exposure from 7 species of mammals. With each specific toxicant a single consistent relationship was observed for all mammals with ν always mammals and then be extended to estimate toxicity at any exposure time with other mammals. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  19. The state of radioactive waste management and of personnel radiation exposure in nuclear power generating facilities in fiscal 1983

    International Nuclear Information System (INIS)

    1985-01-01

    (1) The state of radioactive waste management in nuclear power generating facilities: In the nuclear power stations, the released quantities of radioactive gaseous and liquid wastes are all below the control objective levels. For the respective nuclear power stations, the released quantities of radioactive gaseous and liquid wastes in fiscal 1983 and the objective levels are given in table. And, the quantities of solid wastes taken into storage and the cumulative amounts are given. For reference, the results each year since fiscal 1974 are shown. (2) The state of personnel radiation exposure in nuclear power generating facilities: In the nuclear power stations, the personnel radiation exposures are all below the permissible levels. The dose distribution etc. in the respective nuclear power stations are given in table. For reference, the results each year since fiscal 1974 are shown. (Mori, K.)

  20. Distribution, exposure pathways, sources and toxicity of nonylphenol ...

    African Journals Online (AJOL)

    Water SA. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue ... of their toxicity, oestrogenic properties and widespread contamination. ... to provide better understanding of these emerging environmental contaminants.

  1. Chemical concentrations, exposures, health risks by census tract from National Scale Air Toxics Assessment (NATA)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Chemical concentrations, exposures, health risks by census tract for the United States from National Scale Air Toxics Assessment (NATA). This dataset is associated...

  2. Toxic Effects of a Whole-Body Inhalation Sarin (GR) Vapor Exposure in the Gottingen Minipig

    National Research Council Canada - National Science Library

    Hulet, S. W; Jakubowski, E. M; Dabisch, P. A; Foster, J. S; Miller, D. B; Benton, B. J; Muse, W. T; Way, R. A; Edwards, J. L; McGuire, J.M

    2004-01-01

    .... In order to assess the toxic hazards of such exposures and define chemical defense materiel requirements, it is essential to fill gaps in toxicological databases that define the physiological progression...

  3. Webinar Presentation: Epidemiologic Studies of the Effects of Toxic Exposures on Brain and Behavior: Neuropsychological Assessment

    Science.gov (United States)

    This presentation, Epidemiologic Studies of the Effects of Toxic Exposures on Brain and Behavior: Neuropsychological Assessment, was given at the NIEHS/EPA Children's Centers 2015 Webinar Series: Interdisciplinary Approaches to Neurodevelopment.

  4. DNA repair: As influenced by age, nutrition, and exposure to toxic substances

    International Nuclear Information System (INIS)

    Hart, R.; Chou, Ming; Feuers, R.; Leakey, J.; Duffy, P.; Lyn-Cook, B.; Lipman, J.; Makamura, Kenji; Turturro, A.; Allaben, W.

    1992-01-01

    In evaluating the risk associated with low levels of exposure to toxicants, it is clear that DNA repair, one of the main defenses against agent damage, is not a constant. It can be modified by age, time of day, and physiological state. Nutrition, especially caloric restriction (CR), can modify almost every step in the process of protecting genomic integrity. And history of exposure can modify DNA repair. Thus, the conditions of exposure are almost as important to toxicity as the exposure itself, even at the level of DNA repair. Extrapolation from high to low dose, to be consistent with what is known, should be less a mathematical exercise than an exercise in toxicological judgement, which puts the exposure in proper perspective. This appears to be true at almost every level in the process including a response with a toxic stimulus, even those thought to be very basic, such as DNA repair

  5. Toxicity of platinum, palladium and rhodium to Daphnia magna in single and binary metal exposure experiments.

    Science.gov (United States)

    Zimmermann, Sonja; Wolff, Carolina; Sures, Bernd

    2017-05-01

    Mainly due to automobile traffic, but also due to other sources, the platinum group elements (PGE) platinum (Pt), palladium (Pd) and rhodium (Rh) are introduced into aquatic biotopes where they accumulate in sediments of lakes and rivers. However, the toxicity of these noble metals to aquatic organisms is not well understood and especially toxicity studies under standardized condition are lacking. Thus, the toxicity of Pt, Pd and Rh to Daphnia magna was tested in single metal exposure experiments according to OECD guideline 202. Immobility and lethality was recorded after 24 h and 48 h of exposure and EC 50 and LC 50 , respectively, were determined. As the nominal exposure concentration of Pd differed significantly from the quantified concentration, the control of the real exposure concentration by chemical analysis is mandatory, especially for Pd. The toxicity decreased in the order Pd > Pt ≫ Rh with e.g. LC 50 (48 h) values of 14 μg/L for Pd, 157 μg/L for Pt and 56,800 μg/L for Rh. The exposure period had a clear effect on the toxicity of Pt, Pd and Rh. For Pt and Rh the endpoint immobility was more sensitive than the endpoint lethality whereas Pd toxicity was similar for both endpoints. The Hill slopes, which are a measure for the steepness of the concentration-response curves, showed no significant discrepancies between the different metals. The binary metal exposure to Pt and Pd revealed a more-than-additive, i.e. a synergistic toxicity using the toxic unit approach. The present study is a start to understand the toxicity of interacting PGE. The modes of action behind the synergistic effect are unclear. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. 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.

  7. Formal recycling of e-waste leads to increased exposure to toxic metals: an occupational exposure study from Sweden.

    Science.gov (United States)

    Julander, Anneli; Lundgren, Lennart; Skare, Lizbet; Grandér, Margaretha; Palm, Brita; Vahter, Marie; Lidén, Carola

    2014-12-01

    Electrical and electronic waste (e-waste) contains multiple toxic metals. However, there is currently a lack of exposure data for metals on workers in formal recycling plants. The objective of this study was to evaluate workers' exposure to metals, using biomarkers of exposure in combination with monitoring of personal air exposure. We assessed exposure to 20 potentially toxic metals among 55 recycling workers and 10 office workers at three formal e-waste recycling plants in Sweden. Workers at two of the plants were followed-up after 6 months. We collected the inhalable fraction and OFC (37-mm) fraction of particles, using personal samplers, as well as spot samples of blood and urine. We measured metal concentrations in whole blood, plasma, urine, and air filters using inductively coupled plasma-mass spectrometry following acid digestion. The air sampling indicated greater airborne exposure, 10 to 30 times higher, to most metals among the recycling workers handling e-waste than among the office workers. The exposure biomarkers showed significantly higher concentrations of chromium, cobalt, indium, lead, and mercury in blood, urine, and/or plasma of the recycling workers, compared with the office workers. Concentrations of antimony, indium, lead, mercury, and vanadium showed close to linear associations between the inhalable particle fraction and blood, plasma, or urine. In conclusion, our study of formal e-waste recycling shows that workers performing recycling tasks are exposed to multiple toxic metals. Copyright © 2014. Published by Elsevier Ltd.

  8. ExpoCast: Exposure Science for Prioritization and Toxicity Testing

    Science.gov (United States)

    The US EPA is completing the Phase I pilot for a chemical prioritization research program, called ToxCastTM. Here EPA is developing methods for using computational chemistry, high-throughput screening, and toxicogenomic technologies to predict potential toxicity and prioritize l...

  9. Urban land use, air toxics and public health: Assessing hazardous exposures at the neighborhood scale

    International Nuclear Information System (INIS)

    Corburn, Jason

    2007-01-01

    Land use data are increasingly understood as important indicators of potential environmental health risk in urban areas where micro-scale or neighborhood level hazard exposure data are not routinely collected. This paper aims to offer a method for estimating the distribution of air toxics in urban neighborhoods using land use information because actual air monitoring data rarely exist at this scale. Using Geographic Information System spatial modeling tools, we estimate air toxics concentrations across neighborhoods in New York City and statistically compare our model with the US Environmental Protection Agency's National Air Toxic Assessment and air monitoring data across three NYC neighborhoods. We conclude that land use data can act as a good proxy for estimating neighborhood scale air toxics, particularly in the absence of monitoring data. In addition, the paper suggests that land use data can expand the reach of environmental impact assessments that routinely exclude analyses of potential exposures to urban air toxics at the neighborhood scale

  10. Chronic Toxic Metal Exposure and Cardiovascular Disease: Mechanisms of Risk and Emerging Role of Chelation Therapy.

    Science.gov (United States)

    Aneni, Ehimen C; Escolar, Esteban; Lamas, Gervasio A

    2016-12-01

    Over the last few decades, there has been a growing body of epidemiologic evidence linking chronic toxic metal exposure to cardiovascular disease-related morbidity and mortality. The recent and unexpectedly positive findings from a randomized, double-blind, multicenter trial of metal chelation for the secondary prevention of atherosclerotic cardiovascular disease (Trial to Assess Chelation Therapy (TACT)) have focused the discussion on the role of chronic exposure to toxic metals in the development and propagation of cardiovascular disease and the role of toxic metal chelation therapy in the secondary prevention of cardiovascular disease. This review summarizes the most recent evidence linking chronic toxic metal exposure to cardiovascular disease and examines the findings of TACT.

  11. AGE-RELATED TOXICITY PATHWAY ANALYSIS IN BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    Science.gov (United States)

    The influence of aging on susceptibility to environmental exposures is poorly understood. To investigate-the contribution of different life stages on response to toxicants, we examined the effects of an acute exposure to the volatile organic compound, toluene (0.0 or 1.0 g/kg), i...

  12. The molecular basis of simple relationships between exposure concentration and toxic effects with time.

    Science.gov (United States)

    Tennekes, Henk A; Sánchez-Bayo, Francisco

    2013-07-05

    Understanding the toxicity of chemicals to organisms requires considering the molecular mechanisms involved as well as the relationships between exposure concentration and toxic effects with time. Our current knowledge about such relationships is mainly explained from a toxicodynamic and toxicokinetic perspective. This paper re-introduces an old approach that takes into account the biochemical mode of action and their resulting biological effects over time of exposure. Empirical evidence demonstrates that the Druckrey-Küpfmüller toxicity model, which was validated for chemical carcinogens in the early 1960s, is also applicable to a wide range of toxic compounds in ecotoxicology. According to this model, the character of a poison is primarily determined by the reversibility of critical receptor binding. Chemicals showing irreversible or slowly reversible binding to specific receptors will produce cumulative effects with time of exposure, and whenever the effects are also irreversible (e.g. death) they are reinforced over time; these chemicals have time-cumulative toxicity. Compounds having non-specific receptor binding, or involving slowly reversible binding to some receptors that do not contribute to toxicity, may also be time-dependent; however, their effects depend primarily on the exposure concentration, with time playing a minor role. Consequently, the mechanism of toxic action has important implications for risk assessment. Traditional risk approaches cannot predict the impacts of toxicants with time-cumulative toxicity in the environment. New assessment procedures are needed to evaluate the risk that the latter chemicals pose on humans and the environment. An example is shown to explain how the risk of time-dependent toxicants is underestimated when using current risk assessment protocols. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Birth outcomes among military personnel after exposure to documented open-air burn pits before and during pregnancy.

    Science.gov (United States)

    Conlin, Ava Marie S; DeScisciolo, Connie; Sevick, Carter J; Bukowinski, Anna T; Phillips, Christopher J; Smith, Tyler C

    2012-06-01

    To examine birth outcomes in military women and men with potential exposure to documented open-air burn pits before and during pregnancy. Electronic data from the Department of Defense Birth and Infant Health Registry and the Defense Manpower Data Center were used to examine the prevalence of birth defects and preterm birth among infants of active-duty women and men who were deployed within a 3-mile radius of a documented open-air burn pit before or during pregnancy. In general, burn pit exposure at various times in relation to pregnancy and for differing durations was not consistently associated with an increase in birth defects or preterm birth in infants of active-duty military personnel. These analyses offer reassurance to service members that burn pit exposure is not consistently associated with these select adverse infant health outcomes.

  14. Critical Duration of Exposure for Developmental Chlorpyrifos-Induced Neurobehavioral Toxicity

    OpenAIRE

    Sledge, Damiyon; Yen, Jerry; Morton, Terrell; Dishaw, Laura; Petro, Ann; Donerly, Susan; Linney, Elwood; Levin, Edward D.

    2011-01-01

    Developmental exposure of rats to the pesticide chlorpyrifos (CPF) causes persistent neurobehavioral impairment. In a parallel series of studies with zebrafish, we have also found persisting behavioral dysfunction after developmental CPF exposure. We have developed a battery of measures of zebrafish behavior, which are reliable and sensitive to toxicant-induced damage. This study determined the critical duration of developmental CPF exposure for causing persisting neurobehavioral effects. Tes...

  15. The interventional radiology: means of reduction and optimization of medical personnel exposure

    International Nuclear Information System (INIS)

    Maccia, C.; Vano, E.; Gonzalez, L.; Guibelalde, E.

    1998-01-01

    The measures envisaged to make an optimization of the radiation protection are in the use of materials adapted to the situation, the use of dosemeters devoted to the doses evaluation for particularly sensitive organs , the introduction of ophthalmic examinations and finally, the information and training of every category of personnel in radiation protection. (N.C.)

  16. Smoking among troops deployed in combat areas and its association with combat exposure among navy personnel in Sri Lanka

    Directory of Open Access Journals (Sweden)

    de Silva Varuni

    2012-07-01

    Full Text Available Abstract Background Among military personnel alcohol consumption and binge-drinking have increased but cigarette smoking has declined in the recent past. Although there is a strong association between smoking and PTSD the association between combat exposure and smoking is not clear. Methods This cross sectional study was carried out among representative samples of SLN Special Forces and regular forces deployed in combat areas. Both Special Forces and regular forces were selected using simple random sampling. Only personnel who had served continuously in combat areas during the one year period prior to end of combat operations were included in the study. Females were not included in the sample. The study assessed several mental health outcomes as well as alcohol use, smoking and cannabis use. Sample was classified according to smoking habits as never smokers, past smokers (those who had smoked in the past but not within the past year and current smokers (those smoking at least one cigarette within the past 12 months. Results Sample consisted of 259 Special Forces and 412 regular navy personnel. Prevalence of current smoking was 17.9% (95% CI 14.9-20.8. Of the sample 58.4% had never smoked and 23.7% were past smokers. Prevalence of current smoking was significantly higher among Special Forces personnel compared to regular forces. (OR 1.90 (95% CI 1.20-3.02. Personnel aged ≥35 years had the lowest prevalence of smoking (14.0%. Commissioned officers had a lower prevalence (12.1% than non commissioned officers or other ranks. After adjustment for demographic variables and service type there was significant association between smoking and combat experiences of seeing dead or wounded [OR 1.79 (95%CI 1.08-2.9], handling dead bodies [OR 2.47(95%CI 1.6-3.81], coming under small arms fire [OR 2.01(95%CI 1.28-3.15] and coming under mortar, missile and artillery fire [OR 2.02(95%CI 1.29-3.17]. There was significant association between the number of

  17. Extrapolation for exposure duration in oral toxicity: A quantitative analysis of historical toxicity data

    NARCIS (Netherlands)

    Groeneveld, C.N.; Hakkert, B.C.; Bos, P.M.J.; Heer, C.de

    2004-01-01

    For human risk assessment, experimental data often have to be extrapolated for exposure duration, which is generally done by means of default values. The purpose of the present study was twofold. First, to derive a statistical distribution for differences in exposure duration that can be used in a

  18. Sources of toxicity and exposure information for identifying chemicals of high concern to children

    International Nuclear Information System (INIS)

    Stone, Alex; Delistraty, Damon

    2010-01-01

    Due to the large number of chemicals in commerce without adequate toxicity characterization data, coupled with an ineffective federal policy for chemical management in the United States, many states are grappling with the challenge to identify toxic chemicals that may pose a risk to human health and the environment. Specific populations (e.g., children, elderly) are particularly sensitive to these toxic chemicals. In 2008, the Children's Safe Product Act (CSPA) was passed in Washington State. The CSPA included specific requirements to identify High Priority Chemicals (HPCs) and Chemicals of High Concern to Children (CHCCs). To implement this legislation, a methodology was developed to identify HPCs from authoritative scientific and regulatory sources on the basis of toxicity criteria. Another set of chemicals of concern was then identified from authoritative sources, based on their potential exposure to children. Exposure potential was evaluated by identifying chemicals detected in biomonitoring studies (i.e., human tissues), as well as those present in residential exposure media (e.g., indoor air, house dust, drinking water, consumer products). Accordingly, CHCCs were defined as HPCs that also appear in biomonitoring studies or relevant exposure media. For chemicals with unique Chemical Abstracts Service (CAS) numbers, we identified 2044 HPCs and 2219 chemicals with potential exposure to children, resulting in 476 CHCCs. The process of chemical identification is dynamic, so that chemicals may be added or subtracted as new information becomes available. Although beyond the scope of this paper, the 476 CHCCs will be prioritized in a more detailed assessment, based on the strength and weight of evidence of toxicity and exposure data. Our approach was developed to be flexible which allows the addition or removal of specific sources of toxicity or exposure information, as well as transparent to allow clear identification of inputs. Although the methodology was

  19. Environmental exposure of primary care personnel to ribavirin aerosol when supervising treatment of infants with respiratory syncytial virus infections.

    Science.gov (United States)

    Rodriguez, W J; Bui, R H; Connor, J D; Kim, H W; Brandt, C D; Parrott, R H; Burch, B; Mace, J

    1987-01-01

    The potential exposure to ribavirin aerosol in the environment was assessed in nurses caring for infants and children with severe lower respiratory tract infections due to respiratory syncytial virus. Ribavirin aerosol was administered via a ventilator, oxygen tent, or oxygen hood. Participants worked directly with infants receiving ribavirin for 20.0 to 35.0 h over a 3-day period. No toxic or adverse effects of ribavirin aerosol were observed in any of the 19 nurses studied, and ribavirin was not detected in erythrocytes, plasma, or urine collected after the potential exposure period. PMID:3662474

  20. Effects of subchronic oral toxic metal exposure on the intestinal microbiota of mice

    Institute of Scientific and Technical Information of China (English)

    Qixiao Zhai; Tianqi Li; Leilei Yu; Yue Xiao; Saisai Feng; Jiangping Wu; Jianxin Zhao; Hao Zhang; Wei Chen

    2017-01-01

    Oral exposure to toxic metals such as cadmium (Cd),lead (Pb),copper (Cu) and aluminum (Al) can induce various adverse health effects in humans and animals.However,the effects of these metals on the gut microbiota have received limited attention.The present study demonstrated that long-term toxic metal exposure altered the intestinal microbiota of mice in a metal-specific and time-dependent manner.Subchronic oral Cu exposure for eight weeks caused a profound decline in gut microbial diversity in mice,whereas no significant changes were observed in groups treated with other metals.Cd exposure significantly increased the relative abundances of organisms from the genera Alistipes and Odoribacter and caused marked decreases in Mollicutes and unclassified Ruminococcaceae.Pb exposure significantly decreased the abundances of eight genera:unclassified and uncultured Ruminococcaceae,unclassified Lachnospiraceae,Ruminiclostridium_9,Rikenellaceae_RC9_gut_group,Oscillibacter,Anaerotruncus and Lachnoclostridium.Cu exposure affected abundances of the genera Alistipes,Bacteroides,Ruminococcaceae_UCG-014,Allobaculum,Mollicutes_RFg_norank,Rikenellaceae_RC9_gut_group,Ruminococcaceae_unclassified and Turicibacter.Al exposure increased the abundance of Odoribacter and decreased that of Anaerotruncus.Exposure to any metal for eight weeks significantly decreased the abundance of Akkermansia.These results provide a new understanding regarding the role of toxic metals in the pathogenesis of intestinal and systemic disorders in the host within the gut microbiota framework.

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

    Directory of Open Access Journals (Sweden)

    Hayley Hughes

    2013-01-01

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

  2. Effective energies and exposure determinations of two different energy X-ray beams incident on a personnel monitor

    International Nuclear Information System (INIS)

    Okuno, E.; Cruz, M.T. da

    1984-01-01

    The effective energy of one X or gamma ray beam can be determined by means of two thermoluminescent (TL) dosemeters mounted between suitable filters. However, it has been observed that personnel monitors exposed to two different energy ionizing radiations provide different effective energies depeding on the type of TL phosphor used. This fact could be a powerful tool for identifying exposures to radiation with quite different effective energies which are very common in practice. Two types of TL dosemeters were used : pellets of cold pressed natural fluoride and NaCl developed in our own laboratory, and LiF, TLD-100 from Harshaw Chemical Co.. Experimental results obtained with these combined dosemeters after irradiation with different sets of exposures and energy values of ionizing radiations are also presented. (Author) [pt

  3. Host Response to Environmental Hazards: Using Literature, Bioinformatics, and Computation to Derive Candidate Biomarkers of Toxic Industrial Chemical Exposure

    Science.gov (United States)

    2015-10-01

    military threat chemicals with adverse health effects and clinical outcomes to improve diagnostic potential after exposure to toxic industrial...end organ injury following chemical exposures in the field. Markers of end-organ injury and toxicity and other health effects markers, particularly...Biomarkers of Toxic Industrial Chemical Exposure Major Jonathan D. Stallings *1 , Danielle L. Ippolito 1 , Anders Wallqvist 2 , B. Claire McDyre 3 , and

  4. Childhood trauma exposure and toxic stress: what the PNP needs to know.

    Science.gov (United States)

    Hornor, Gail

    2015-01-01

    Trauma exposure in childhood is a major public health problem that can result in lifelong mental and physical health consequences. Pediatric nurse practitioners must improve their skills in the identification of trauma exposure in children and their interventions with these children. This continuing education article will describe childhood trauma exposure (adverse childhood experiences) and toxic stress and their effects on the developing brain and body. Adverse childhood experiences include a unique set of trauma exposures. The adverse childhood experiences or trauma discussed in this continuing education offering will include childhood exposure to emotional abuse, physical abuse, sexual abuse, emotional neglect, physical neglect, domestic violence, household substance abuse, household mental illness, parental separation or divorce, and a criminal household member. Thorough and efficient methods of screening for trauma exposure will be discussed. Appropriate intervention after identification of trauma exposure will be explored. Copyright © 2015 National Association of Pediatric Nurse Practitioners. Published by Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    2014-09-12

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

  6. Investigating Epigenetic Effects of Prenatal Exposure to Toxic Metals in Newborns: Challenges and Benefits.

    Science.gov (United States)

    Nye, Monica D; Fry, Rebecca C; Hoyo, Cathrine; Murphy, Susan K

    2014-01-01

    Increasing evidence suggest that epigenetic alterations can greatly impact human health, and that epigenetic mechanisms (DNA methylation, histone modifications, and microRNAs) may be particularly relevant in responding to environmental toxicant exposure early in life. The epigenome plays a vital role in embryonic development, tissue differentiation and disease development by controlling gene expression. In this review we discuss what is currently known about epigenetic alterations in response to prenatal exposure to inorganic arsenic (iAs) and lead (Pb), focusing specifically on their effects on DNA methylation. We then describe how epigenetic alterations are being studied in newborns as potential biomarkers of in utero environmental toxicant exposure, and the benefits and challenges of this approach. In summary, the studies highlighted herein indicate how epigenetic mechanisms are impacted by early life exposure to iAs and Pb, and the research that is being done to move towards understanding the relationships between toxicant-induced epigenetic alterations and disease development. Although much remains unknown, several groups are working to understand the correlative and causal effects of early life toxic metal exposure on epigenetic changes and how these changes may result in later development of disease.

  7. 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.

  8. 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

  9. Annual course of retraining for the occupational exposure personnel of the laboratory of internal dosimetry

    International Nuclear Information System (INIS)

    Alfaro L, M.M.

    2002-09-01

    The general objective of this report is to instruct the personnel in the basic concepts of radiological protection and in the Manual of Procedures of Radiological Safety of the Laboratory of Internal Dosimetry. Also, to exchange experiences during the activities that are carried out in the laboratory and in the knowledge of abnormal situations. The referred Manual consists of 14 procedures and 5 instructions which are listed in annex of this document. The content of this course consists of three topics: 1. Basic principles of radiological protection to reduce the received dose equivalent. 2. Use of radiation measurer equipment. 3. Emergency procedures of the laboratory of internal dosimetry. (Author)

  10. An exposure-response database for detailed toxicity data

    International Nuclear Information System (INIS)

    Woodall, George M.

    2008-01-01

    Risk assessment for human health effects often depends on evaluation of toxicological literature from a variety of sources. Risk assessors have limited resources for obtaining raw data, performing follow-on analyses or initiating new studies. These constraints must be balanced against a need to improve scientific credibility through improved statistical and analytical methods that optimize the use of available information. Computerized databases are used in toxicological risk assessment both for storing data and performing predictive analyses. Many systems provide primarily either bibliographic information or summary factual data from toxicological studies; few provide adequate information to allow application of dose-response models. The Exposure-Response database (ERDB) described here fills this gap by allowing entry of sufficiently detailed information on experimental design and results for each study, while limiting data entry to the most relevant. ERDB was designed to contain information from the open literature to support dose-response assessment and allow a high level of automation in performance of various types of dose-response analyses. Specifically, ERDB supports emerging analytical approaches for dose-response assessment, while accommodating the diverse nature of published literature. Exposure and response data are accessible in a relational multi-table design, with closely controlled standard fields for recording values and free-text fields to describe unique aspects of the study. Additional comparative analyses are made possible through summary tables and graphic representations of the data contained within ERDB

  11. Development of pulmonary oxygen toxicity in rats after hyperoxic exposure

    Directory of Open Access Journals (Sweden)

    Siermontowski Piotr

    2014-06-01

    Full Text Available The aim of the study was to examine the effects of hyperbaric oxygen on lung aeration on an animal experimental model and compare the obtained results with the anticipated scope of damage to pulmonary parenchyma in humans under the same exposure conditions. The research was carried out on Black Hood rats that were kept in a hyperbaric chamber designed for animals in an atmosphere of pure oxygen and at overpressures of 0.15, 0.2, 0.3, 0.4, and 0.5 MPa for 1, 2 or 4 h. After sacrificing the animals, histopathological specimens were obtained encompassing cross-sections of entire lungs, which were subjected to qualitative and quantitative examination with the use of the 121-point Haug grid. A statistically significant decrease in pulmonary parenchyma was observed as a result of an increasing oxygen partial pressure as well as with prolonged exposure time. The intensification of changes observed was much higher than expected on the basis of calculations performed with the use of tables.

  12. Neurodevelopmental toxicity risks due to occupational exposure to industrial chemicals during pregnancy

    DEFF Research Database (Denmark)

    Julvez, Jordi; Grandjean, Philippe

    2009-01-01

    Exposure to neurotoxic chemicals is of particular concern when it occurs during early development. The immature brain is highly vulnerable prenatally and is therefore at risk due to occupational exposures incurred by pregnant women. A systematic search of the literature has been performed...... by occupational health researchers and practitioners from the need to protect pregnant workers. Due to the vulnerability of the brain during early development, a precautionary approach to neurodevelopmental toxicity needs to be applied in occupational health....

  13. Toxic effects of juvenile sablefish, Anoplopoma fimbria by ammonia exposure at different water temperature.

    Science.gov (United States)

    Kim, Jun-Hwan; Park, Hee-Ju; Hwang, In-Ki; Han, Jae-Min; Kim, Do-Hyung; Oh, Chul Woong; Lee, Jung-Sick; Kang, Ju-Chan

    2017-09-01

    Juvenile sablefish, Anoplopoma fimbria (mean length 17.1±2.4cm, and mean weight 75.6±5.7g) were used to evaluate toxic effects on antioxidant systems, immune responses, and stress indicators by ammonia exposure (0, 0.25, 0.75, and 1.25mg/L) at different water temperature (12 and 17°C) in 1 and 2 months. In antioxidant responses, superoxide dismutase (SOD) and catalase (CAT) were significantly increased by ammonia exposure, whereas glutathione (GSH) was decreased. In immune responses, lysozyme and phagocytosis activity were significantly increased by ammonia exposure. In stress indicators, plasma glucose, heat shock protein 70 (HSP 70), and cortisol were significantly increased. At high water temperature (17°C), alterations by ammonia exposure were more distinctly. The results of this study indicated that ammonia exposure can induce toxic effects in the sablefish, and high water temperature can affect the ammonia exposure toxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. A colorimetric sensor array for identification of toxic gases below permissible exposure limits†

    OpenAIRE

    Feng, Liang; Musto, Christopher J.; Kemling, Jonathan W.; Lim, Sung H.; Suslick, Kenneth S.

    2010-01-01

    A colorimetric sensor array has been developed for the rapid and sensitive detection of 20 toxic industrial chemicals (TICs) at their PELs (permissible exposure limits). The color changes in an array of chemically responsive nanoporous pigments provide facile identification of the TICs with an error rate below 0.7%.

  15. Response of the nonbiting midge Chironomus riparius to multigeneration toxicant exposure

    NARCIS (Netherlands)

    Marinković, M.; de Bruijn, K.; Asselman, M.; Bogaert, M.; Jonker, M.J.; Kraak, M.H.S.; Admiraal, W.

    2012-01-01

    The ability of the nonbiting midge Chironomus riparius to withstand long-term toxicant exposure has been attributed to genetic adaptation. Recently, however, evidence has arisen that supports phenotypic plasticity. Therefore, the present study aimed to investigate if Chironomus riparius indeed copes

  16. Sacrifice zones: the front lines of toxic chemical exposure in the United States

    National Research Council Canada - National Science Library

    Lerner, Steve

    2010-01-01

    ... States of America. Library of Congress Cataloging-in-Publication Data Lerner, Steve. Sacrifice zones: the front lines of toxic chemical exposure in the United States / Steve Lerner. p. cm. Includes bibliographical references and index. ISBN 978-0-262-01440-3 (hardcover : alk. paper) 1. Environmental toxicology- United States- Case studies. 2. Che...

  17. TOXICITY PATHWAY ANALYSIS IN AGING BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    Science.gov (United States)

    The influence of aging on susceptibility to environmental stressors is poorly understood. To investigate the contribution of different life stages on response to toxicants, we examined the effects of acute exposure by oral gavage of the volatile organic solvent toluene (0.00, 0.3...

  18. Transuranium element toxicity: dose-response relationships at low exposure levels. Summary and speculative interpretation relative to exposure limits

    International Nuclear Information System (INIS)

    Thompson, R.C.

    1975-01-01

    A summary is given of information on transuranium element toxicity and the correlation of this information with current established exposure limits. It is difficult to calculate a biologically relevant radiation dose from deposited plutonium; it is exposure that must be controlled in order to prevent biological effect, and if the relationship between exposure and effect is known, then radiation dose is of no concern. There are extensive data on the effects of plutonium in bone. Results of studies at the University of Utah indicate that plutonium in beagles may be as much as ten times more toxic than radium. It has been suggested that this toxicity ratio may be even higher in man than in the beagle dog because of differences in surface-to-volume ratios and differences in the rate of burial of surface-deposited plutonium. The present capabilities for extrapolating dose-effect relationships seem to be limited to the setting of upper limits, based on assumptions of linearity and considerations related to natural background

  19. Cumulative toxicity of neonicotinoid insecticide mixtures to Chironomus dilutus under acute exposure scenarios.

    Science.gov (United States)

    Maloney, Erin M; Morrissey, Christy A; Headley, John V; Peru, Kerry M; Liber, Karsten

    2017-11-01

    Extensive agricultural use of neonicotinoid insecticide products has resulted in the presence of neonicotinoid mixtures in surface waters worldwide. Although many aquatic insect species are known to be sensitive to neonicotinoids, the impact of neonicotinoid mixtures is poorly understood. In the present study, the cumulative toxicities of binary and ternary mixtures of select neonicotinoids (imidacloprid, clothianidin, and thiamethoxam) were characterized under acute (96-h) exposure scenarios using the larval midge Chironomus dilutus as a representative aquatic insect species. Using the MIXTOX approach, predictive parametric models were fitted and statistically compared with observed toxicity in subsequent mixture tests. Single-compound toxicity tests yielded median lethal concentration (LC50) values of 4.63, 5.93, and 55.34 μg/L for imidacloprid, clothianidin, and thiamethoxam, respectively. Because of the similar modes of action of neonicotinoids, concentration-additive cumulative mixture toxicity was the predicted model. However, we found that imidacloprid-clothianidin mixtures demonstrated response-additive dose-level-dependent synergism, clothianidin-thiamethoxam mixtures demonstrated concentration-additive synergism, and imidacloprid-thiamethoxam mixtures demonstrated response-additive dose-ratio-dependent synergism, with toxicity shifting from antagonism to synergism as the relative concentration of thiamethoxam increased. Imidacloprid-clothianidin-thiamethoxam ternary mixtures demonstrated response-additive synergism. These results indicate that, under acute exposure scenarios, the toxicity of neonicotinoid mixtures to C. dilutus cannot be predicted using the common assumption of additive joint activity. Indeed, the overarching trend of synergistic deviation emphasizes the need for further research into the ecotoxicological effects of neonicotinoid insecticide mixtures in field settings, the development of better toxicity models for neonicotinoid mixture

  20. In utero exposure to toxic air pollutants and risk of childhood autism.

    Science.gov (United States)

    von Ehrenstein, Ondine S; Aralis, Hilary; Cockburn, Myles; Ritz, Beate

    2014-11-01

    Genetic and environmental factors are believed to contribute to the development of autism, but relatively few studies have considered potential environmental risks. Here, we examine risks for autism in children related to in utero exposure to monitored ambient air toxics from urban emissions. Among the cohort of children born in Los Angeles County, California, 1995-2006, those whose mothers resided during pregnancy in a 5-km buffer around air toxics monitoring stations were included (n = 148,722). To identify autism cases in this cohort, birth records were linked to records of children diagnosed with primary autistic disorder at the California Department of Developmental Services between 1998 and 2009 (n = 768). We calculated monthly average exposures during pregnancy for 24 air toxics selected based on suspected or known neurotoxicity or neurodevelopmental toxicity. Factor analysis helped us identify the correlational structure among air toxics, and we estimated odds ratios (ORs) for autism from logistic regression analyses. Autism risks were increased per interquartile range increase in average concentrations during pregnancy of several correlated toxics mostly loading on 1 factor, including 1,3-butadiene (OR = 1.59 [95% confidence interval = 1.18-2.15]), meta/para-xylene (1.51 [1.26-1.82]), other aromatic solvents, lead (1.49 [1.23-1.81]), perchloroethylene (1.40 [1.09-1.80]), and formaldehyde (1.34 [1.17-1.52]), adjusting for maternal age, race/ethnicity, nativity, education, insurance type, parity, child sex, and birth year. Risks for autism in children may increase following in utero exposure to ambient air toxics from urban traffic and industry emissions, as measured by community-based air-monitoring stations.

  1. Heavy metals toxicity after acute exposure of cultured renal cells. Intracellular accumulation and repartition

    International Nuclear Information System (INIS)

    Khodja, Hicham; Carriere, Marie; Avoscan, Laure; Gouget, Barbara

    2005-01-01

    Lead (Pb), cadmium (Cd) and uranium (U) present no known biological function but are toxic in various concentration ranges. Pb and Cd lead generally to nephrotoxicity consisting in proximal renal tubular dysfunction and accumulation while U has been reported to induce chemical kidney toxicity, functional and histological damages being as well mainly observed in proximal tubule cells. This work address the question of Cd, Pb, and U cytotoxicity, intracellular accumulation and repartition after acute intoxication of renal proximal tubule epithelial cells. After cells exposure to different concentrations of metals for various times, morphological changes were observed and intracellular concentrations and distributions of toxic metals were specified by PIXE coupled to RBS. Cell viability, measured by biochemical tests, was used as toxicity indicator. A direct correlation between cytotoxicity and intracellular accumulation in renal epithelial cells have been established. Finally, intracellular Pb and U localizations were detected while Cd was found to be uniformly distributed in renal cells. (author)

  2. Interactive toxicity of chlorpyrifos and parathion in neonatal rats: Role of esterases in exposure sequence-dependent toxicity

    International Nuclear Information System (INIS)

    Kacham, R.; Karanth, S.; Baireddy, P.; Liu, J.; Pope, C.

    2006-01-01

    We previously reported that sequence of exposure to chlorpyrifos and parathion in adult rats can markedly influence toxic outcome. In the present study, we evaluated the interactive toxicity of chlorpyrifos (8 mg/kg, po) and parathion (0.5 mg/kg, po) in neonatal (7 days old) rats. Rats were exposed to the insecticides either concurrently or sequentially (separated by 4 h) and sacrificed at 4, 8, and 24 h after the first exposure for biochemical measurements (cholinesterase activity in brain, plasma, and diaphragm and carboxylesterase activity in plasma and liver). The concurrently-exposed group showed more cumulative lethality (15/24) than either of the sequential dosing groups. With sequential dosing, rats treated initially with chlorpyrifos prior to parathion (C/P) exhibited higher lethality (7/23) compared to those treated with parathion before chlorpyrifos (P/C; 1/24). At 8 h after initial dosing, brain cholinesterase inhibition was significantly greater in the C/P group (59%) compared to the P/C group (28%). Diaphragm and plasma cholinesterase activity also followed a relatively similar pattern of inhibition. Carboxylesterase inhibition in plasma and liver was relatively similar among the treatment groups across time-points. Similar sequence-dependent differences in brain cholinesterase inhibition were also noted with lower binary exposures to chlorpyrifos (2 mg/kg) and parathion (0.35 mg/kg). In vitro and ex vivo studies compared relative oxon detoxification of carboxylesterases (calcium-insensitive) and A-esterases (calcium-sensitive) in liver homogenates from untreated and insecticide pretreated rats. Using tissues from untreated rats, carboxylesterases detoxified both chlorpyrifos oxon and paraoxon, while A-esterases only detoxified chlorpyrifos oxon. With parathion pretreatment, A-esterases still detoxified chlorpyrifos oxon while liver from chlorpyrifos pretreated rats had little apparent effect on paraoxon. We conclude that while neonatal rats are less

  3. Diuron exposure induces systemic and organ-specific toxicity following acute and sub-chronic exposure in male Wistar rats.

    Science.gov (United States)

    Domingues, Alexandre; Barbisan, Luis Fernando; Martins, Priscila Raquel; Spinardi-Barbisan, Ana Lúcia Tozzi

    2011-05-01

    Diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] is a substitute urea herbicide widely used on agricultural crops with potential mutagenic, teratogenic, reproductive and carcinogenic effects. Nonetheless, its toxic potential on the immune system needs a detailed assessment. Thus, in order to evaluate the adverse effect of this herbicide on lymphohematopoietic organs and macrophage activity, male Wistar rats were orally treated with Diuron at 125, 1250 and 2500 ppm for 14, 28 or 90 days. General signs of toxicity were observed in Diuron-treated groups (1250 and 2500 ppm), including reduced food intake and body weight gain, as well as higher relative weights for spleen, kidneys and liver (28 and 90-day toxicity studies) and elevated serum levels of ALT, albumin, total protein, creatinine and urea (28-day toxicity study). Diuron exposure caused a severe depletion of splenic white pulp compartments and cellularity, followed by a decreased number of CD4(+) T lymphocytes, increased extramedullary hematopoiesis and deposition of hemosiderin in red pulp. Despite alteration in macrophage spreading, the macrophagic activity was not significantly affected by the herbicide. Under these experimental conditions, the results suggest that Diuron exerts systemic and target-organ toxicity, mainly at higher concentration. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Effect of nutritional state on Hsp60 levels in the rotifer Brachionus plicatilis following toxicant exposure.

    Science.gov (United States)

    Wheelock, C E; Baumgartner, T A; Newman, J W; Wolfe, M F; Tjeerdema, R S

    2002-11-13

    The nutritional state of an organism can affect the results of toxicity testing. Here we exemplified this fact by examining the effect of nutritional deprivation on heat shock protein 60 (hsp60) production in the rotifer Brachionus plicatilis following exposure to two proven inducers of hsp60, a water-accommodated fraction of crude oil (WAF) and a dispersed oil preparation (DO). Both DO and WAF exposures of unfed rotifers resulted in significantly greater hsp60 levels than that of fed DO and WAF exposed rotifers at 8 h: 870 and 3100% of control, respectively. Results clearly demonstrate that a poor nutritional state potentiates stress protein induction upon exposure to water-soluble petroleum products. It is therefore critical to define the organismal nutritional status when reporting toxic responses. Copyright 2002 Elsevier Science B.V.

  5. Calibration of personnel monitors by exposure to gamma radiation with energies up to 9 MeV

    International Nuclear Information System (INIS)

    Leao, J.L.B.; Cunha, P.G. da; Diz, R.; Oberhofer, M.

    Occupational exposure with photons of high energy (higher than those from 60 Co) might occur from nuclear reactors and accelerators. Radiation monitors for absorbed dose determination, however, often do not have a wall thickness sufficient to establish electronical equilibrium in that energy range. Using calibration factors determined for lower energies (calibration factors for 60 Co radiation) might cause a significant underestimation of the soft tissue absorbed dose. The calibration factor of the personnel monitors of the Eberline Instrument Co.based on TL dosimeters of LiF is reported. This monitor was calibrated with 9 MeV photons produced by thermal neutrons capture in a Nitarget, at an absorbed dose rate of 125 rads/h at the C.E.N. in France. The results are compared with the corresponding calibration factors for different energies up to 60 Co radiation determined in the IRD (Instituto de Radioprotecao e Dosimetria Rio de Janeiro). (Author) [pt

  6. Assessment of occupational exposure of medical personnel to inhalatory anesthetics in Poland

    Directory of Open Access Journals (Sweden)

    Małgorzata Kucharska

    2014-02-01

    Full Text Available Objectives: Despite common use of inhalatory anesthetics, such as nitrous oxide (N2O, halothane, sevoflurane, and the like, occupational exposure to these substances in operating theatres was not monitored in Poland until 2006. The situation changed when maximum admissible concentration (MAC values for anesthetics used in Poland were established in 2005 for N2O, and in 2007 for sevoflurane, desflurane and isoflurane. The aim of this work was to assess occupational exposure in operating rooms on the basis of reliable and uniform analytical procedures. Material and Methods: The method for the determination of all anesthetics used in Poland, i.e. nitrous oxide, sevoflurane, isoflurane, desflurane, and halothane, was developed and validated. The measurements were performed in 2006-2010 in 31 hospitals countrywide. The study covered 117 operating rooms; air samples were collected from the breathing zone of 146 anesthesiologists, and 154 nurses, mostly anaesthetic. The measurements were carried out during various surgical operations, mostly on adult patients but also in hospitals for children. Results: Time weighted average concentrations of the anesthetics varied considerably, and the greatest differences were noted for N2O (0.1-1438.5 mg/m3; 40% of the results exceeded the MAC value. Only 3% of halothane, and 2% of sevoflurane concentrations exceeded the respective MAC values. Conclusions: Working in operating theatres is dangerous to the health of the operating staff. The coefficient of combined exposure to anesthesiologists under study exceeded the admissible value in 130 cases, which makes over 40% of the whole study population. Most of the excessive exposure values were noted for nitrous oxide. Med Pr 2014;65(1:43–54

  7. Anesthetic exposure and health of dental personnel, 1 June 1978-30 November 1980

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, E.N.

    1980-01-01

    An epidemiologic survey was conducted to determine possible health hazards in the dental profession, with particular attention being given to the results of exposure to anesthetic gases. The survey contacted 30,650 dentists and 30,547 chairside assistants who were subsequently grouped according to exposure to inhalation anesthetics in the dental operatory during the course of their employment experience. An increase in liver disease 1.7 above that expected was noted in male dentists heavily exposed to anesthetics, combined with a 1.2 fold increase for kidney disease and 1.9-fold increase for neurological disease. The spontaneous abortion rate in wives of male dentists was 1.5-fold higher than expected. Occupational exposure to anesthetics, either direct or indirect, was associated with significant increases in spontaneous abortion over control levels during the first and second trimester of pregnancy. Women who smoked during pregnancy showed increased risk of spontaneous abortion, with a 27% increase occurring in dental assistants and a 21% increase in wives of dentists. A 34% increased risk of babies having congenital abnormalities was noted among smoking dental assistants.

  8. Estimating children's exposure to toxic elements in contaminated toys and children's jewelry via saliva mobilization.

    Science.gov (United States)

    Guney, Mert; Nguyen, Alain; Zagury, Gerald J

    2014-09-19

    Children's potential for exposure to potentially toxic elements in contaminated jewelry and toys via mouth contact has not yet been fully evaluated. Various toys and jewelry (metallic toys and jewelry [MJ], plastic toys, toys with paint or coating, and brittle/pliable toys; n = 32) were tested using the saliva extraction (mouthing) compartment of the DIN and RIVM bioaccessibility protocols to assess As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, Sb, and Se mobilization via saliva. Total concentrations of As, Cd, Cu, Ni, Pb, and Sb were found elevated in analyzed samples. Four metals were mobilized to saliva from 16 MJ in significant quantities (>1 μg for highly toxic Cd and Pb, >10 μg for Cu and Ni). Bioaccessible concentrations and hazard index values for Cd exceeded limit values, for young children between 6 mo- and 3 yr-old and according to both protocols. Total and bioaccessible metal concentrations were different and not always correlated, encouraging the use of bioaccessibility for more accurate hazard assessments. Bioaccessibility increased with increasing extraction time. Overall, the risk from exposure to toxic elements via mouthing was high only for Cd and for MJ. Further research on children's exposure to toxic elements following ingestion of toy or jewelry material is recommended.

  9. Toxicity assessment of Chlorella vulgaris and Chlorella protothecoides following exposure to Pb(II).

    Science.gov (United States)

    Zhang, Wei; Xiong, Bang; Chen, Lin; Lin, Kuangfei; Cui, Xinhong; Bi, Huasong; Guo, Meijin; Wang, Weiliang

    2013-07-01

    The short- and long-term toxic effects of Pb(II) exposure on Chlorella vulgaris (C. vulgaris) and Chlorella protothecoides (C. protothecoides) were not well understood. The lab study was performed to observe the Pb(II) exposure induced changes. Results of the observations show: (1) higher level of Pb(II) (50 or 80mgL(-1)) could significantly inhibit the growth and chlorophyll a synthesis of both algae in almost all the treatments and dose-response relationships could be clearly observed, (2) the range of EC50 values (24-120h, 67.73-172.45mgL(-1)) indicated that Pb(II) had a relatively limited short-term toxicity to the two algae, while long-term tests (7-28d, 50.41-63.91mgL(-1)) displayed higher toxicity and (3) SOD and CAT activities of both algae after exposed to medium level of Pb(II) were significantly promoted, and their response might be more susceptible in short-term exposure. This research provides a basic understanding of Pb(II) toxicity to aquatic organisms. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Evaluation of silica nanoparticle toxicity after topical exposure for 90 days

    Directory of Open Access Journals (Sweden)

    Ryu HJ

    2014-12-01

    Full Text Available Hwa Jung Ryu,1,* Nak-won Seong,2,* Byoung Joon So,1 Heung-sik Seo,2 Jun-ho Kim,2 Jeong-Sup Hong,2 Myeong-kyu Park,2 Min-Seok Kim,2 Yu-Ri Kim,3 Kyu-Bong Cho,4 Mu yeb Seo,2 Meyoung-Kon Kim,3 Eun Ho Maeng,2 Sang Wook Son1 1Department of Dermatology, Korea University College of Medicine, Seoul, South Korea; 2Korea Testing and Research Institute, Gyunggi-Do, South Korea; 3Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul, South Korea; 4Department of Clinical Laboratory Science, Shinheung College, Uijeongbu, South Korea *These authors contributed equally to this work Abstract: Silica is a very common material that can be found in both crystalline and amorphous forms. Well-known toxicities of the lung can occur after exposure to the crystalline form of silica. However, the toxicities of the amorphous form of silica have not been thoroughly studied. The majority of in vivo studies of amorphous silica nanoparticles (NPs were performed using an inhalation exposure method. Since silica NPs can be commonly administered through the skin, a study of dermal silica toxicity was necessary to determine any harmful effects from dermal exposures. The present study focused on the results of systemic toxicity after applying 20 nm colloidal silica NPs on rat skin for 90 days, in accordance with the Organization for Economic Cooperation and Development test guideline 411 with a good laboratory practice system. Unlike the inhalation route or gastrointestinal route, the contact of silica NPs through skin did not result in any toxicity or any change in internal organs up to a dose of 2,000 mg/kg in rats. Keywords: silica nanoparticles, toxicity, dermal route

  11. Salicylate Toxicity from Genital Exposure to a Methylsalicylate-Containing Rubefacient

    Science.gov (United States)

    Thompson, Trevonne M.; Toerne, Theodore; Erickson, Timothy B.

    2016-01-01

    Methylsalicylate-containing rubefacients have been reported to cause salicylate poisoning after ingestion, topical application to abnormal skin, and inappropriate topical application to normal skin. Many over-the-counter products contain methylsalicylate. Topical salicylates rarely produce systemic toxicity when used appropriately; however, methylsaliclyate can be absorbed through intact skin. Scrotal skin can have up to 40-fold greater absorption compared to other dermal regions. We report a unique case of salicylate poisoning resulting from the use of a methylsalicylate-containing rubefacient to facilitate masturbation in a male teenager. Saliclyate toxicity has not previously been reported from the genital exposure to methylsaliclyate. PMID:26973745

  12. Evaluation of exposure limits to toxic gases for nuclear reactor control room operators

    International Nuclear Information System (INIS)

    Mahlum, D.D.; Sasser, L.B.

    1991-07-01

    We have evaluated ammonia, chlorine, Halon (actually a generic name for several halogenated hydro-carbons), and sulfur dioxide for their possible effects during an acute two-minute exposure in order to derive recommendations for maximum exposure levels. To perform this evaluation, we conducted a search to find the most pertinent literature regarding toxicity in humans and in experimental animals. Much of the literature is at least a decade old, not an unexpected finding since acute exposures are less often performed now than they were a few years ago. In most cases, the studies did not specifically examine the effects of two-minute exposures; thus, extrapolations had to be made from studies of longer-exposure periods. Whenever possible, we gave the greatest weight to human data, with experimental animal data serving to strengthen the conclusion arrived at from consideration of the human data. Although certain individuals show hypersensitivity to materials like sulfur dioxide, we have not attempted to factor this information into the recommendations. After our evaluation of the data in the literature, we held a small workshop. Major participants in this workshop were three consultants, all of whom were Diplomates of the American Board of Toxicology, and staff from the Nuclear Regulatory Commission. Our preliminary recommendations for two-minute exposure limits and the rationale for them were discussed and consensus reached on final recommendations. These recommendations are: (1) ammonia-300 to 400-ppm; (2) chlorine-30 ppm; (3) Halon 1301-5%; Halon 1211-2%; and (4) sulfur dioxide-100 ppm. Control room operators should be able to tolerate two-minute exposures to these levels, don fresh-air masks, and continue to operate the reactor if the toxic material is eliminated, or safely shut down the reactor if the toxic gas remains. 96 refs., 9 tabs

  13. Anticoagulant rodenticide toxicity to non-target wildlife under controlled exposure conditions

    Science.gov (United States)

    Rattner, Barnett A.; Mastrota, F. Nicholas; van den Brink, Nico; Elliott, J.; Shore, R.; Rattner, B.

    2018-01-01

    Much of our understanding of anticoagulant rodenticide toxicity to non-target wildlife has been derived from molecular through whole animal research and registration studies in domesticated birds and mammals, and to a lesser degree from trials with captive wildlife. Using these data, an adverse outcome pathway identifying molecular initiating and anchoring events (inhibition of vitamin K epoxide reductase, failure to activate clotting factors), and established and plausible linkages (coagulopathy, hemorrhage, anemia, reduced fitness) associated with toxicity, is presented. Controlled exposure studies have demonstrated that second-generation anticoagulant rodenticides (e.g., brodifacoum) are more toxic than first- and intermediate-generation compounds (e.g., warfarin, diphacinone), however the difference in potency is diminished when first- and intermediate-generation compounds are administered on multiple days. Differences in species sensitivity are inconsistent among compounds. Numerous studies have compared mortality rate of predators fed prey or tissue containing anticoagulant rodenticides. In secondary exposure studies in birds, brodifacoum appears to pose the greatest risk, with bromadiolone, difenacoum, flocoumafen and difethialone being less hazardous than brodifacoum, and warfarin, coumatetralyl, coumafuryl, chlorophacinone and diphacinone being even less hazardous. In contrast, substantial mortality was noted in secondary exposure studies in mammals ingesting prey or tissue diets containing either second- or intermediate-generation compounds. Sublethal responses (e.g., prolonged clotting time, reduced hematocrit and anemia) have been used to study the sequelae of anticoagulant intoxication, and to some degree in the establishment of toxicity thresholds or toxicity reference values. Surprisingly few studies have undertaken histopathological evaluations to identify cellular lesions and hemorrhage associated with anticoagulant rodenticide exposure in non

  14. Developmental toxicity from exposure to various forms of mercury compounds in medaka fish (Oryzias latipes embryos

    Directory of Open Access Journals (Sweden)

    Wu Dong

    2016-08-01

    Full Text Available This study examined developmental toxicity of different mercury compounds, including some used in traditional medicines. Medaka (Oryzias latipes embryos were exposed to 0.001–10 µM concentrations of MeHg, HgCl2, α-HgS (Zhu Sha, and β-HgS (Zuotai from stage 10 (6–7 hpf to 10 days post fertilization (dpf. Of the forms of mercury in this study, the organic form (MeHg proved the most toxic followed by inorganic mercury (HgCl2, both producing embryo developmental toxicity. Altered phenotypes included pericardial edema with elongated or tube heart, reduction of eye pigmentation, and failure of swim bladder inflation. Both α-HgS and β-HgS were less toxic than MeHg and HgCl2. Total RNA was extracted from survivors three days after exposure to MeHg (0.1 µM, HgCl2 (1 µM, α-HgS (10 µM, or β-HgS (10 µM to examine toxicity-related gene expression. MeHg and HgCl2 markedly induced metallothionein (MT and heme oxygenase-1 (Ho-1, while α-HgS and β-HgS failed to induce either gene. Chemical forms of mercury compounds proved to be a major determinant in their developmental toxicity.

  15. Beta Radiation Exposure of Personnel in Radiosynovectomy and at the Production of Eye Application

    International Nuclear Information System (INIS)

    Mielcarek, J.; Barth, I.

    2001-01-01

    Full text: Beta radionuclides are increasingly used in nuclear medicine therapy. In a study of exposure at working places with supposed enhanced radiation risk the followings are monitored: 1. Production of eye applicators ( 106 Ru/ 106 Rh) for therapy of intraocular tumours. During the processes radionuclides are used in sealed and unsealed form. 2. Radiosynovectomy (RSO). This therapy is often used in treatment of inflammatory joint disease. The radionuclides 169 Er, 186 Re and 90 Y are applied in form of radioactive solutions. A complex of problems has to be solved here: Handling of high activities (several GBq per day), very small distances between source and skin, high risk of skin contamination, unsatisfactory dose measurement techniques. In our investigations high sensitive thin thermoluminescence dosimeters (LiF:Mg,Cu,P) were used to determine the skin dose of the hands especially fingertips during preparation and application of the radioactive substances at several institutions. During production of eye applicators we found hand doses essentially below the annual limit. But direct radiation at RSO caused more than 100 mSv at the fingertips per working day in some cases. Even higher doses (more than 50% of the annual limit for skin during a working day) were caused by contamination of the hands. By use of manipulators, wearing of appropriate protection gloves and by improvement of directions for work, the radiation exposure could be reduced dramatically. Consequences for individual beta dosimetry and with respect to license of use of beta radionuclides are discussed. (author)

  16. Feeding behavior of the invasive bivalve Limnoperna fortunei (Dunker, 1857 under exposure to toxic cyanobacteria Microcystis aeruginosa

    Directory of Open Access Journals (Sweden)

    V Gazulha

    Full Text Available The aim of this study was to test the effects of cyanobacteria toxicity on feeding behavior of the golden mussel Limnoperna fortunei. First, it was tested the hypothesis that L. fortunei preferentially graze on non-toxic phytoplankton and reject toxic cyanobacteria. Second, it was tested the hypothesis that toxic cyanobacteria negatively affect feeding and survival of L. fortunei. The present study is the first to evaluate the effects of toxic cyanobacteria on L. fortunei feeding and survival. In the short-term grazing, golden mussel filtration rates were evaluated in the presence of toxic and non-toxic strains of cyanobacteria Microcystis aeruginosa, and non-toxic phytoplankton Nitzschia palea. Highest filtration rates were registered when mussels fed on Nitzschia. Despite that, golden mussel expelled Nitzschia cells in large quantities and preferentially ingested Microcystis cells, both toxic and non-toxic strains. In the long-term grazing, mussels were exposed to toxic and non-toxic strains of Microcystis during 5 days. Filtration rates were not significantly different for toxic and non-toxic Microcystis throughout exposure period. The results have demonstrated cyanobacteria toxicity is not the main factor influencing L. fortunei feeding behavior. Survival of L. fortunei feeding on toxic cyanobacteria shows the potential of this invasive bivalve as a vector to the transference of cyanotoxins to higher trophic levels.

  17. Gloves, extra gloves or special types of gloves for preventing percutaneous exposure injuries in healthcare personnel.

    Science.gov (United States)

    Mischke, Christina; Verbeek, Jos H; Saarto, Annika; Lavoie, Marie-Claude; Pahwa, Manisha; Ijaz, Sharea

    2014-03-07

    Healthcare workers are at risk of acquiring viral diseases such as hepatitis B, hepatitis C and HIV through exposure to contaminated blood and body fluids at work. Most often infection occurs when a healthcare worker inadvertently punctures the skin of their hand with a sharp implement that has been used in the treatment of an infected patient, thus bringing the patient's blood into contact with their own. Such occurrences are commonly known as percutaneous exposure incidents. To determine the benefits and harms of extra gloves for preventing percutaneous exposure incidents among healthcare workers versus no intervention or alternative interventions. We searched CENTRAL, MEDLINE, EMBASE, NHSEED, Science Citation Index Expanded, CINAHL, NIOSHTIC, CISDOC, PsycINFO and LILACS until 26 June 2013. Randomised controlled trials (RCTs) with healthcare workers as the majority of participants, extra gloves or special types of gloves as the intervention, and exposure to blood or bodily fluids as the outcome. Two authors independently assessed study eligibility and risk of bias, and extracted data. We performed meta-analyses for seven different comparisons. We found 34 RCTs that included 6890 person-operations as participating units and reported on 46 intervention-control group comparisons. We grouped interventions as follows: increased layers of standard gloves, gloves manufactured with special protective materials or thicker gloves, and gloves with puncture indicator systems. Indicator gloves show a coloured spot when they are perforated. Participants were surgeons in all studies and they used at least one pair of standard gloves as the control intervention. Twenty-seven studies also included other surgical staff (e.g. nurses). All but one study used perforations in gloves as an indication of exposure. The median control group rate was 18.5 perforations per 100 person-operations. Seven studies reported blood stains on the skin and two studies reported self reported

  18. Determination of internal exposure doses of the personnel of uranium-mining company due to radon isotopes decay products

    International Nuclear Information System (INIS)

    Sevostyanov, V.N.

    2004-01-01

    This work carries out a determination of individual doses of internal exposure of the staff of the uranium-mining company in Kazakhstan due to radon decay products. The company extracts uranium by in-situ leaching. After leaching, uranium is sorbed from a solution in facilities where the staff is located. The state of three uranium mines was analyzed. The dose determination was conducted in tune with the proposed method by using integral alpha-tracking detectors to identify the content of 222 Rn and express appliances to identify the content of radio-active aerosols in air of the working area for determination the equilibrium coefficient. The measurements were performed within one year. The work produced the results in average annual values of radon and thoron decay products activity concentration and variation, equilibrium coefficient variation, and so-called expressive-to-integral value conversion factor. The obtained personnel's individual radiation doses due to radon exposure for this period lie within the range of < 1 mSv/year. (author)

  19. Evaluation of external radiation exposure of personnel involved in veterinary nuclear medicine

    International Nuclear Information System (INIS)

    Komatsubara, N.; Ito, N.; Natsuhori, M.; Sano, T.; Ishikawa, T.; Hatakeyama, S.; Futatsugawa, S.; Terasaki, K.; Hirayama, H.

    2005-01-01

    Veterinary nuclear medicine has been widely applied in the US and Europe, especially for dogs, cats, and horses. The needs of the nuclear medicine in veterinary practice are also growing in Japan. This study was performed in order to make a safety guideline for veterinary nuclear medicine in Japan. Two sorts of well often medically used radionuclide, 18 F and 99m Tc were chosen for evaluating the exposed doses of the veterinarian, the animal owner, and the general public. Air absorption doses around a physical phantom containing radioactive materials ( 18 F or 99m Tc) were measured by glass dosimeters. (Asahi Techno Glass Ltd.) It was verified that the measurement values were corresponding to the calculation values using EGS4. Then, canine pectoral and abdominal mathematical phantom was designed, external radiation exposure of the veterinarian, the animal owner and the public from the phantom containing radioactive materials were calculated by using EGS4. Calculated exposure doses were compared with the dose limit or the dose constraint. (20mSv/yr for the veterinarian: ICRP, 5mSv/yr for the animal owner: IAEA, and 1mSv/yr for the general public: ICRP 2 ). The future integration exposed doses of the animal owner and the public didn't exceed the dose constraint or the dose limit at the release after 24 hours of the radiopharmaceutical administering. In this study, all the calculation conditions were set up on the safety side. Therefore, it is thought that actual exposed doses lower considerably. The safety guideline for the veterinary nuclear medicine in Japan will be established by further application of this type of research. (author)

  20. Cancer risk of incremental exposure to polycyclic aromatic hydrocarbons in electrocautery smoke for mastectomy personnel.

    Science.gov (United States)

    Tseng, Hsin-Shun; Liu, Shi-Ping; Uang, Shi-Nian; Yang, Li-Ru; Lee, Shien-Chih; Liu, Yao-Jen; Chen, Dar-Ren

    2014-02-04

    Electrocautery applications in surgical operations produce evasive odorous smoke in the cleanest operation rooms. Because of the incomplete combustion of electrical current in the tissues and blood vessels during electrocautery applications, electrocautery smoke (ES) containing significant unknown chemicals and biological forms is released. The potential hazards and cancer risk should be further investigated from the perspective of the occupational health of surgical staff. The particle number concentration and the concentration of polycyclic aromatic hydrocarbons (PAHs) in ES were thoroughly investigated in 10 mastectomies to estimate the cancer risk for surgical staff. The particle number concentration and gaseous/particle PAHs at the surgeons' and anesthetic technologists' (AT) breathing heights were measured with a particle counter and filter/adsorbent samplers. PAHs were soxhlet-extracted, cleaned, and analyzed by gas chromatography/mass spectrometry. Abundant submicron particles and high PAH concentrations were found in ES during regular surgical mastectomies. Most particles in ES were in the size range of 0.3 to 0.5 μm, which may potentially penetrate through the medical masks into human respiration. The average particle/gaseous phase PAH concentrations at the surgeon's breathing height were 131 and 1,415 ng/m³, respectively, which is 20 to 30 times higher than those in regular outdoor environments. By using a toxicity equivalency factor, the cancer risk for the surgeons and anesthetic technologists was calculated to be 117 × 10(-6) and 270 × 10(-6), respectively; the higher cancer risk for anesthetic technologists arises due to the longer working hours in operation rooms. The carcinogenic effects of PAHs in ES on the occupational health of surgical staff should not be neglected. The use of an effective ES evacuator or smoke removal apparatus is strongly suggested to diminish the ES hazards to surgical staff.

  1. 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.

  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. Toxicants exposures as novel zoonoses: reflections on sustainable development, food safety and veterinary public health.

    Science.gov (United States)

    Frazzoli, C; Mantovani, A

    2010-12-01

    The modern concept of zoonosis considers any detriment to the health and/or quality of human life resulting from relationships with (other) vertebrate or edible or toxic invertebrate animals. Whereas exposure to toxicants through foods of animal origin (a.o.) is a well-established issue, hereby we discuss it as novel zoonoses, from the standpoints of health implications as well as similarities and differences with classical zoonoses caused by biological agents. Novel toxicant-related zoonoses are linked with new issues in food safety, such as the environment-feed-food chain. In fact, the potential effect of the combined and repeated exposure to dietary toxicants is generally long-term and not readily discernible. Endocrine disrupting chemicals in staple foods of a.o. are discussed as a telling example of a food safety issue summing up critical points covered by the definition of sustainable development, also implicating health risks for generations to come. We suggest some critical points to implement the veterinary public health action in sustainable food safety, such as enhancement of Hazard Analysis and Critical Control Points systems for toxicological risk management. © 2010 Blackwell Verlag GmbH.

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

    OpenAIRE

    M B Abubakar; W Z Abdullah; S A Sulaiman; F E Uboh; B S Ang

    2013-01-01

    Summary. Different health risks including haematotoxicity and weight loss have been reported for gasoline. Supplementation with antioxidants such as vitamins A, C, and E has been shown to ameliorate the toxicity effects of gasoline vapours exposure. Honey contains vitamins, and polyphenols that possess good antioxidant properties. The potential role of honey in preventing gasoline-induced haematotoxicity and weight loss was assessed in male rats. The rats were exposed to gasoline (11.13±1.1cm...

  5. Investigating Epigenetic Effects of Prenatal Exposure to Toxic Metals in Newborns: Challenges and Benefits

    OpenAIRE

    Nye, Monica D.; Fry, Rebecca C.; Hoyo, Cathrine; Murphy, Susan K.

    2014-01-01

    Increasing evidence suggest that epigenetic alterations can greatly impact human health, and that epigenetic mechanisms (DNA methylation, histone modifications, and microRNAs) may be particularly relevant in responding to environmental toxicant exposure early in life. The epigenome plays a vital role in embryonic development, tissue differentiation and disease development by controlling gene expression. In this review we discuss what is currently known about epigenetic alterations in response...

  6. Overlapping toxic effect of long term thallium exposure on white mustard (Sinapis alba L.) photosynthetic activity.

    Science.gov (United States)

    Mazur, Radosław; Sadowska, Monika; Kowalewska, Łucja; Abratowska, Agnieszka; Kalaji, Hazem M; Mostowska, Agnieszka; Garstka, Maciej; Krasnodębska-Ostręga, Beata

    2016-09-02

    Heavy metal exposure affect plant productivity by interfering, directly and indirectly, with photosynthetic reactions. The toxic effect of heavy metals on photosynthetic reactions has been reported in wide-ranging studies, however there is paucity of data in the literature concerning thallium (Tl) toxicity. Thallium is ubiquitous natural trace element and is considered the most toxic of heavy metals; however, some plant species, such as white mustard (Sinapis alba L.) are able to accumulate thallium at very high concentrations. In this study we identified the main sites of the photosynthetic process inhibited either directly or indirectly by thallium, and elucidated possible detoxification mechanisms in S. alba. We studied the toxicity of thallium in white mustard (S. alba) growing plants and demonstrated that tolerance of plants to thallium (the root test) decreased with the increasing Tl(I) ions concentration in culture media. The root growth of plants exposed to Tl at 100 μg L(-1) for 4 weeks was similar to that in control plants, while in plants grown with Tl at 1,000 μg L(-1) root growth was strongly inhibited. In leaves, toxic effect became gradually visible in response to increasing concentration of Tl (100 - 1,000 μg L(-1)) with discoloration spreading around main vascular bundles of the leaf blade; whereas leaf margins remained green. Subsequent structural analyses using chlorophyll fluorescence, microscopy, and pigment and protein analysis have revealed different effects of varying Tl concentrations on leaf tissue. At lower concentration partial rearrangement of the photosynthetic complexes was observed without significant changes in the chloroplast structure and the pigment and protein levels. At higher concentrations, the decrease of PSI and PSII quantum yields and massive oxidation of pigments was observed in discolored leaf areas, which contained high amount of Tl. Substantial decline of the photosystem core proteins and disorder of the

  7. Exposure dose estimation of nursing personnel and visitors following "1"2"5I brachytherapy

    International Nuclear Information System (INIS)

    Nakazato, Kazuhisa; Kikuchi, Hirosumi; Hotta, Harumi; Nishizawa, Kunihide

    2007-01-01

    An automated access management system to the controlled sickrooms for "1"2"5I brachytherapy was developed. The system consists of access control and video surveillance units. The patients implanted "1"2"5I seeds were isolated for about 20 h after surgery in the controlled sickrooms. The maximum doses and dose rates of the nurses and visitors were estimated by using the legal upper limit activity of 1,300 MBq, the measured longest staying time, and the shortest distance between the patients and individuals. Video analysis revealed activities of the nurses, patients, and visitors in the controlled sickroom, and relationships between the access frequency and staying time. The nurses' measured doses ranged from 1 to 3 μSv, and averaged 1.6 μSv. The nurses' maximum dose and dose rate were 16 μSv and 5.6 nSv·h"-"1·MBq"-"1. The visitors' maximum dose and dose rate were 6 μSv and 2.6 nSv·h"-"1·MBq"-"1. The nurses and visitors' exposure doses per patient were estimated to be negligible compared with the annual limit of the public. (author)

  8. ON THE ADVISABILITY OF REJECTION OF SUBTRACTION OF BACKGROUND DOSIMETERS INDICATION VALUES FROM THE MEASURED VALUES OF INDIVIDUAL DOSES OF OCCUPATIONAL EXPOSURE OF A-GROUP PERSONNEL

    Directory of Open Access Journals (Sweden)

    A. N. Barkovskiy

    2013-01-01

    Full Text Available An article contains substantiation of advisability of rejection of subtraction of background dosimeters indication values from the measured values of individual doses of occupational exposure of A-group personnel in the process of carrying out of individual dosimetry control of medical organizations stuff which was implemented in the Methodical Guideline 2.6.1.3015-12. It is shown that mentioned procedure is firstly incorrect when we deal with low doses, when the impact of natural exposure could be really considerable and secondary senseless when we deal with dose values close to the dose limit value for A-group personnel when the impact of natural exposure is much lower then the error of measurements. It is suggested to carry out the account of the impact of natural exposure into personnel average doses basing on the analysis of statistical distributions of personnel individual doses and on indications of background dosimeters. It is suggested to add the information about indications of background dosimeters into the Base of Federal Statistical Supervision № 1-DOS as it is prescribed in the Methodical Guideline 2.6.1.3015-12. This article is the respond to the article of A.I. Grigoriev published in the present issue of Journal, in which the author contests the reasonableness of this provision.

  9. Exposure to Prescription Drugs Labeled for Risk of Adverse Effects of Suicidal Behavior or Ideation among 100 Air Force Personnel Who Died by Suicide, 2006-2009

    Science.gov (United States)

    Lavigne, Jill E.; McCarthy, Michael; Chapman, Richard; Petrilla, Allison; Knox, Kerry L.

    2012-01-01

    Prescription drugs for many indications are labeled with warnings for potential risk of suicidal ideation or behavior. Exposures to prescription drugs labeled for adverse effects of suicidal behavior or ideation among 100 Air Force personnel who died by suicide between 2006 and 2009 are described. Air Force registry data were linked to…

  10. Occupational health of miners at altitude: adverse health effects, toxic exposures, pre-placement screening, acclimatization, and worker surveillance.

    Science.gov (United States)

    Vearrier, David; Greenberg, Michael I

    2011-08-01

    Mining operations conducted at high altitudes provide health challenges for workers as well as for medical personnel. To review the literature regarding adverse health effects and toxic exposures that may be associated with mining operations conducted at altitude and to discuss pre-placement screening, acclimatization issues, and on-site surveillance strategies. We used the Ovid ( http://ovidsp.tx.ovid.com ) search engine to conduct a MEDLINE search for "coal mining" or "mining" and "altitude sickness" or "altitude" and a second MEDLINE search for "occupational diseases" and "altitude sickness" or "altitude." The search identified 97 articles of which 76 were relevant. In addition, the references of these 76 articles were manually reviewed for relevant articles. CARDIOVASCULAR EFFECTS: High altitude is associated with increased sympathetic tone that may result in elevated blood pressure, particularly in workers with pre-existing hypertension. Workers with a history of coronary artery disease experience ischemia at lower work rates at high altitude, while those with a history of congestive heart failure have decreased exercise tolerance at high altitude as compared to healthy controls and are at higher risk of suffering an exacerbation of their heart failure. PULMONARY EFFECTS: High altitude is associated with various adverse pulmonary effects, including high-altitude pulmonary edema, pulmonary hypertension, subacute mountain sickness, and chronic mountain sickness. Mining at altitude has been reported to accelerate silicosis and other pneumoconioses. Miners with pre-existing pneumoconioses may experience an exacerbation of their condition at altitude. Persons traveling to high altitude have a higher incidence of Cheyne-Stokes respiration while sleeping than do persons native to high altitude. Obesity increases the risk of pulmonary hypertension, acute mountain sickness, and sleep-disordered breathing. NEUROLOGICAL EFFECTS: The most common adverse neurological

  11. Human skeletal muscle drug transporters determine local exposure and toxicity of statins.

    Science.gov (United States)

    Knauer, Michael J; Urquhart, Bradley L; Meyer zu Schwabedissen, Henriette E; Schwarz, Ute I; Lemke, Christopher J; Leake, Brenda F; Kim, Richard B; Tirona, Rommel G

    2010-02-05

    The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, or statins, are important drugs used in the treatment and prevention of cardiovascular disease. Although statins are well tolerated, many patients develop myopathy manifesting as muscle aches and pain. Rhabdomyolysis is a rare but severe toxicity of statins. Interindividual differences in the activities of hepatic membrane drug transporters and metabolic enzymes are known to influence statin plasma pharmacokinetics and risk for myopathy. Interestingly, little is known regarding the molecular determinants of statin distribution into skeletal muscle and its relevance to toxicity. We sought to identify statin transporters in human skeletal muscle and determine their impact on statin toxicity in vitro. We demonstrate that the uptake transporter OATP2B1 (human organic anion transporting polypeptide 2B1) and the efflux transporters, multidrug resistance-associated protein (MRP)1, MRP4, and MRP5 are expressed on the sarcolemmal membrane of human skeletal muscle fibers and that atorvastatin and rosuvastatin are substrates of these transporters when assessed using a heterologous expression system. In an in vitro model of differentiated, primary human skeletal muscle myoblast cells, we demonstrate basal membrane expression and drug efflux activity of MRP1, which contributes to reducing intracellular statin accumulation. Furthermore, we show that expression of human OATP2B1 in human skeletal muscle myoblast cells by adenoviral vectors increases intracellular accumulation and toxicity of statins and such effects were abrogated when cells overexpressed MRP1. These results identify key membrane transporters as modulators of skeletal muscle statin exposure and toxicity.

  12. Toxic industrial chemicals and chemical weapons: exposure, identification, and management by syndrome.

    Science.gov (United States)

    Tomassoni, Anthony J; French, Robert N E; Walter, Frank G

    2015-02-01

    Toxidromes aid emergency care providers in the context of the patient presenting with suspected poisoning, unexplained altered mental status, unknown hazardous materials or chemical weapons exposure, or the unknown overdose. The ability to capture an adequate chemical exposure history and to recognize toxidromes may reduce dependence on laboratory tests, speed time to delivery of specific antidote therapy, and improve selection of supportive care practices tailored to the etiologic agent. This article highlights elements of the exposure history and presents selected toxidromes that may be caused by toxic industrial chemicals and chemical weapons. Specific antidotes for toxidromes and points regarding their use, and special supportive measures, are presented. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. 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.

  14. Gene networks and toxicity pathways induced by acute cadmium exposure in adult largemouth bass (Micropterus salmoides).

    Science.gov (United States)

    Mehinto, Alvine C; Prucha, Melinda S; Colli-Dula, Reyna C; Kroll, Kevin J; Lavelle, Candice M; Barber, David S; Vulpe, Christopher D; Denslow, Nancy D

    2014-07-01

    Cadmium is a heavy metal that can accumulate to toxic levels in the environment leading to detrimental effects in animals and humans including kidney, liver and lung injuries. Using a transcriptomics approach, genes and cellular pathways affected by a low dose of cadmium were investigated. Adult largemouth bass were intraperitoneally injected with 20μg/kg of cadmium chloride (mean exposure level - 2.6μg of cadmium per fish) and microarray analyses were conducted in the liver and testis 48h after injection. Transcriptomic profiles identified in response to cadmium exposure were tissue-specific with the most differential expression changes found in the liver tissues, which also contained much higher levels of cadmium than the testis. Acute exposure to a low dose of cadmium induced oxidative stress response and oxidative damage pathways in the liver. The mRNA levels of antioxidants such as catalase increased and numerous transcripts related to DNA damage and DNA repair were significantly altered. Hepatic mRNA levels of metallothionein, a molecular marker of metal exposure, did not increase significantly after 48h exposure. Carbohydrate metabolic pathways were also disrupted with hepatic transcripts such as UDP-glucose, pyrophosphorylase 2, and sorbitol dehydrogenase highly induced. Both tissues exhibited a disruption of steroid signaling pathways. In the testis, estrogen receptor beta and transcripts linked to cholesterol metabolism were suppressed. On the contrary, genes involved in cholesterol metabolism were highly increased in the liver including genes encoding for the rate limiting steroidogenic acute regulatory protein and the catalytic enzyme 7-dehydrocholesterol reductase. Integration of the transcriptomic data using functional enrichment analyses revealed a number of enriched gene networks associated with previously reported adverse outcomes of cadmium exposure such as liver toxicity and impaired reproduction. Copyright © 2014 Elsevier B.V. All rights

  15. Water-Based Automobile Paints Potentially Reduce the Exposure of Refinish Painters to Toxic Metals

    Directory of Open Access Journals (Sweden)

    Der-Jen Hsu

    2018-05-01

    Full Text Available Exposure to lead-containing dusts is a global public health concern. This work addresses an important issue of whether eco-friendly water-based paints reduce the exposure potential of auto-repainting workers to metals. With this aim, metal levels in automobile paints and worker metal exposure were measured using both solvent- and water-based paints. The levels of metals, and particularly Pb, Cr (total, Fe, and Cu, in solvent-based paints varied greatly among colors and brands. Lead concentrations ranged from below the detection limit (~0.25 μg/g to 107,928 μg/g (dry film across all samples. In water-based paints, the concentrations of Pb and Cr (total were generally two to three orders of magnitude lower, but the concentrations of Al and Cu exceeded those in some solvent-based paints. The personal short-term exposure of workers who applied water-based paints of popular colors, such as black and white, were generally low, with Pb levels of less than <4 µg/m3 and Cr (total levels of less than 1 µg/m3. Conversely, mean short-term exposure to Pb during the painting of a yellow cab using solvent-based paints were 2028 µg/m3, which was ~14 times the Taiwan short-term permissible exposure limit, while the mean level of exposure to Cr (total was 290 µg/m3, which was well below the exposure limit. This study demonstrates that water-based paints reduce the exposure potential to lead, and highlights the importance of source control in limiting the toxic metals in paints.

  16. Repeated exposure to iron oxide nanoparticles causes testicular toxicity in mice.

    Science.gov (United States)

    Sundarraj, Kiruthika; Manickam, Vijayprakash; Raghunath, Azhwar; Periyasamy, Madhivadhani; Viswanathan, Mangala Priya; Perumal, Ekambaram

    2017-02-01

    The aim of this study was to determine whether repeated exposure to iron oxide nanoparticles (Fe 2 O 3 -NPs) could be toxic to mice testis. Fe 2 O 3 -NPs (25 and 50 mg/kg) were intraperitoneally administered into mice once a week for 4 weeks. Our study showed that Fe 2 O 3 -NPs have the ability to cross the blood-testis barrier to get into the testis. The findings showed that exposure resulted in the accumulation of Fe 2 O 3 -NPs which was evidenced from the iron content and accumulation in the testis. Furthermore, 25 and 50 mg/kg Fe 2 O 3 -NPs administration increased the reactive oxygen species, lipid peroxidation, protein carbonyl content, glutathione peroxidase activity, and nitric oxide levels with a concomitant decrease in the levels of antioxidants-superoxide dismutase, catalase, glutathione, and vitamin C. Increased expression of Bax, cleaved-caspase-3, and cleaved-PARP confirms apoptosis. Serum testosterone levels increased with increased concentration of Fe 2 O 3 -NPs exposure. In addition, the histopathological lesions like vacuolization, detachment, and sloughing of germ cells were also observed in response to Fe 2 O 3 -NPs treatment. The data from our study entailed that testicular toxicity caused by Fe 2 O 3 -NPs exposure may be associated with Fe 2 O 3 -NPs accumulation leading to oxidative stress and apoptosis. Therefore, precautions should be taken in the safe use of Fe 2 O 3 -NPs to avoid complications in the fertility of males. Further research will unravel the possible molecular mechanisms on testicular toxicity of Fe 2 O 3 -NPs. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 594-608, 2017. © 2016 Wiley Periodicals, Inc.

  17. Carcinogenic Air Toxics Exposure and Their Cancer-Related Health Impacts in the United States.

    Directory of Open Access Journals (Sweden)

    Ying Zhou

    Full Text Available Public health protection from air pollution can be achieved more effectively by shifting from a single-pollutant approach to a multi-pollutant approach. To develop such multi-pollutant approaches, identifying which air pollutants are present most frequently is essential. This study aims to determine the frequently found carcinogenic air toxics or hazardous air pollutants (HAPs combinations across the United States as well as to analyze the health impacts of developing cancer due to exposure to these HAPs. To identify the most commonly found carcinogenic air toxics combinations, we first identified HAPs with cancer risk greater than one in a million in more than 5% of the census tracts across the United States, based on the National-Scale Air Toxics Assessment (NATA by the U.S. EPA for year 2005. We then calculated the frequencies of their two-component (binary, and three-component (ternary combinations. To quantify the cancer-related health impacts, we focused on the 10 most frequently found HAPs with national average cancer risk greater than one in a million. Their cancer-related health impacts were calculated by converting lifetime cancer risk reported in NATA 2005 to years of healthy life lost or Disability-Adjusted Life Years (DALYs. We found that the most frequently found air toxics with cancer risk greater than one in a million are formaldehyde, carbon tetrachloride, acetaldehyde, and benzene. The most frequently occurring binary pairs and ternary mixtures are the various combinations of these four air toxics. Analysis of urban and rural HAPs did not reveal significant differences in the top combinations of these chemicals. The cumulative annual cancer-related health impacts of inhaling the top 10 carcinogenic air toxics included was about 1,600 DALYs in the United States or 0.6 DALYs per 100,000 people. Formaldehyde and benzene together contribute nearly 60 percent of the total cancer-related health impacts. Our study shows that although

  18. Carcinogenic Air Toxics Exposure and Their Cancer-Related Health Impacts in the United States.

    Science.gov (United States)

    Zhou, Ying; Li, Chaoyang; Huijbregts, Mark A J; Mumtaz, M Moiz

    2015-01-01

    Public health protection from air pollution can be achieved more effectively by shifting from a single-pollutant approach to a multi-pollutant approach. To develop such multi-pollutant approaches, identifying which air pollutants are present most frequently is essential. This study aims to determine the frequently found carcinogenic air toxics or hazardous air pollutants (HAPs) combinations across the United States as well as to analyze the health impacts of developing cancer due to exposure to these HAPs. To identify the most commonly found carcinogenic air toxics combinations, we first identified HAPs with cancer risk greater than one in a million in more than 5% of the census tracts across the United States, based on the National-Scale Air Toxics Assessment (NATA) by the U.S. EPA for year 2005. We then calculated the frequencies of their two-component (binary), and three-component (ternary) combinations. To quantify the cancer-related health impacts, we focused on the 10 most frequently found HAPs with national average cancer risk greater than one in a million. Their cancer-related health impacts were calculated by converting lifetime cancer risk reported in NATA 2005 to years of healthy life lost or Disability-Adjusted Life Years (DALYs). We found that the most frequently found air toxics with cancer risk greater than one in a million are formaldehyde, carbon tetrachloride, acetaldehyde, and benzene. The most frequently occurring binary pairs and ternary mixtures are the various combinations of these four air toxics. Analysis of urban and rural HAPs did not reveal significant differences in the top combinations of these chemicals. The cumulative annual cancer-related health impacts of inhaling the top 10 carcinogenic air toxics included was about 1,600 DALYs in the United States or 0.6 DALYs per 100,000 people. Formaldehyde and benzene together contribute nearly 60 percent of the total cancer-related health impacts. Our study shows that although there are many

  19. Pulmonary Toxicity and Modifications in Iron Homeostasis Following Libby Amphibole Asbestos Exposure in Rat Models of Cardiovascular Disease

    Science.gov (United States)

    Rationale: Individuals suffering from cardiovascular disease (CVD) develop iron dysregulation which may influence pulmonary toxicity and injury upon exposure to asbestos. We hypothesized spontaneously hypertensive (SH) and spontaneously hypertensive heart failure (SHHF) rats woul...

  20. Toxicity and Metabolites of 2,4,6- Trinitrotoluene (TNT) in Plants and Worms from Exposure to Aged Soil

    National Research Council Canada - National Science Library

    Best, Elly

    2004-01-01

    .... Short-term exposure tests were conducted to explore the acute toxicity for the test organisms of TNT-spiked artificial soils and of the aged TNT-contaminated soil to be included in the subsequent...

  1. Development and demonstration of surveillance and diagnostics of rotating machinery for reducing radiation exposure to nuclear power plant personnel: Appendices: Final report

    International Nuclear Information System (INIS)

    Allen, J.W.; Bohanick, J.S.

    1988-01-01

    This program was designed to reduce radiation exposure to power plant personnel resulting from inspection, maintenance, and repair of rotating equipment. The new rotating machinery monitoring system for this program was installed at GGNS during August 1983. The following nine appendices are presented: signals monitored at GGNS; definition of characterized spectral values; instructions for alignment and balance programs; machine diagrams; FFT program; software module descriptions; sample radiation survey forms used for exposure study; radiation exposure compared to other plants; and a technical section instruction for the vibration monitoring program at GGNS

  2. Mechanisms of the Testis Toxicity Induced by Chronic Exposure to Mequindox

    Directory of Open Access Journals (Sweden)

    Qianying Liu

    2017-09-01

    Full Text Available Mequindox (MEQ is a synthetic antimicrobial agent widely used in China since the 1980s. Although the toxicity of MEQ is well recognized, its testis toxicity has not been adequately investigated. In the present study, we provide evidence that MEQ triggers oxidative stress, mitochondrion dysfunction and spermatogenesis deficiency in mice after exposure to MEQ (0, 25, 55, and 110 mg/kg in the diet for up to 18 months. The genotoxicity and adrenal toxicity may contribute to sperm abnormalities caused by MEQ. Moreover, using LC/MS-IT-TOF analysis, two metabolites, 3-methyl-2-(1-hydroxyethyl quinoxaline-N4-monoxide (M4 and 3-methyl-2-(1-hydroxyethyl quinoxaline-N1-monoxide (M8, were detected in the serum of mice, which directly confirms the relationship between the N→O group reduction metabolism of MEQ and oxidative stress. Interestingly, only M4 was detected in the testes, suggesting that the higher reproductive toxicity of M4 than M8 might be due to the increased stability of M4-radical (M4-R compared to M8-radical (M8-R. Furthermore, the expression of the blood-testis barrier (BTB-associated junctions such as tight junctions, gap junctions and basal ectoplasmic specializations were also examined. The present study demonstrated for the first time the role of the M4 in testis toxicity, and illustrated that the oxidative stress, mitochondrion dysfunction and interference in spermatogenesis, as well as the altered expression of BTB related junctions, were involved in the reproductive toxicity mediated by MEQ in vivo.

  3. Toxic effects of erythromycin, ciprofloxacin and sulfamethoxazole exposure to the antioxidant system in Pseudokirchneriella subcapitata

    International Nuclear Information System (INIS)

    Nie Xiangping; Liu Binyang; Yu Huijuan; Liu Weiqiu; Yang Yufeng

    2013-01-01

    We tested antioxidant responses of the green microalga Pseudokirchneriella subcapitata exposed to different concentrations of the three antibiotics erythromycin (ETM), ciprofloxacin (CPF) and sulfamethoxazole (SMZ). Measurements included the level of lipid peroxidation, the total antioxidative capacity and three major antioxidant mechanisms: the ascorbate–glutathione cycle, the xanthophyll cycle and the enzyme activities of catalase (CAT), superoxide dismutase (SOD), guaiacol glutathione peroxidase (GPX) and glutathione-S-transferase (GST). Three antibiotics significantly affect the antioxidant system of P. subcapitata, but in different ways the alga was more tolerant to CPF and SMZ exposures than to ETM exposure. ETM caused reductions in AsA and GSH biosynthesis, ascorbate–glutathione cycle, xanthophylls cycle and antioxidant enzyme activities. The toxicity of CPF seems to be mainly overcome via induction of the ascorbate–glutathione cycle and CAT, SOD and GPX activities, while the toxicity of SMZ on the photosynthetic apparatus is predominantly reduced by the xanthophyll cycle and GST activity. - Highlights: ► Antibiotics may affect the antioxidant system of Pseudokirchneriella subcapitata. ► Erythromycin decreased AsA, GSH biosynthesis and antioxidant enzyme activities. ► Ciprofloxacin and sulfamethoxazole were lower toxic than erythromycin. - Antibiotics (Erythromycin, ciprofloxacin and sulfamethoxazole) cause the change of antioxidant system and lead to oxidative stress to a green microalga, Pseudokirchneriella subcapitata.

  4. Dose-rate effects of ethylene oxide exposure on developmental toxicity.

    Science.gov (United States)

    Weller, E; Long, N; Smith, A; Williams, P; Ravi, S; Gill, J; Henessey, R; Skornik, W; Brain, J; Kimmel, C; Kimmel, G; Holmes, L; Ryan, L

    1999-08-01

    In risk assessment, evaluating a health effect at a duration of exposure that is untested involves assuming that equivalent multiples of concentration (C) and duration (T) of exposure have the same effect. The limitations of this approach (attributed to F. Haber, Zur Geschichte des Gaskrieges [On the history of gas warfare], in Funf Vortrage aus den Jahren 1920-1923 [Five lectures from the years 1920-1923], 1924, Springer, Berlin, pp. 76-92), have been noted in several studies. The study presented in this paper was designed to specifically look at dose-rate (C x T) effects, and it forms an ideal case study to implement statistical models and to examine the statistical issues in risk assessment. Pregnant female C57BL/6J mice were exposed, on gestational day 7, to ethylene oxide (EtO) via inhalation for 1.5, 3, or 6 h at exposures that result in C x T multiples of 2100 or 2700 ppm-h. EtO was selected because of its short half-life, documented developmental toxicity, and relevance to exposures that occur in occupational settings. Concurrent experiments were run with animals exposed to air for similar periods. Statistical analysis using models developed to assess dose-rate effects revealed significant effects with respect to fetal death and resorptions, malformations, crown-to-rump length, and fetal weight. Animals exposed to short, high exposures of EtO on day 7 of gestation were found to have more adverse effects than animals exposed to the same C x T multiple but at longer, lower exposures. The implication for risk assessment is that applying Haber's Law could potentially lead to an underestimation of risk at a shorter duration of exposure and an overestimation of risk at a longer duration of exposure. Further research, toxicological and statistical, are required to understand the mechanism of the dose-rate effects, and how to incorporate the mechanistic information into the risk assessment decision process.

  5. Comparative proteomic analysis reveals heart toxicity induced by chronic arsenic exposure in rats

    International Nuclear Information System (INIS)

    Huang, Qingyu; Xi, Guochen; Alamdar, Ambreen; Zhang, Jie; Shen, Heqing

    2017-01-01

    Arsenic is a widespread metalloid in the environment, which poses a broad spectrum of adverse effects on human health. However, a global view of arsenic-induced heart toxicity is still lacking, and the underlying molecular mechanisms remain unclear. By performing a comparative quantitative proteomic analysis, the present study aims to investigate the alterations of proteome profile in rat heart after long-term exposure to arsenic. As a result, we found that the abundance of 81 proteins were significantly altered by arsenic treatment (35 up-regulated and 46 down-regulated). Among these, 33 proteins were specifically associated with cardiovascular system development and function, including heart development, heart morphology, cardiac contraction and dilation, and other cardiovascular functions. It is further proposed that the aberrant regulation of 14 proteins induced by arsenic would disturb cardiac contraction and relaxation, impair heart morphogenesis and development, and induce thrombosis in rats, which is mediated by the Akt/p38 MAPK signaling pathway. Overall, these findings will augment our knowledge of the involved mechanisms and develop useful biomarkers for cardiotoxicity induced by environmental arsenic exposure. - Highlights: • Arsenic exposure has been associated with a number of adverse health effects. • The molecular mechanisms involved in arsenic-induced cardiotoxicity remain unclear. • Differential proteins were identified in arsenic-exposed rat heart by proteomics. • Arsenic induces heart toxicity through the Akt/p38 MAPK signaling pathway. - Label-free quantitative proteomic analysis of rat heart reveals putative mechanisms and biomarkers for arsenic-induced cardiotoxicity.

  6. A Review of Environmental Occurrence, Fate, Exposure, and Toxicity of Benzothiazoles.

    Science.gov (United States)

    Liao, Chunyang; Kim, Un-Jung; Kannan, Kurunthachalam

    2018-05-01

    Benzothiazole and its derivatives (BTs) are high production volume chemicals that have been used for several decades in a large number of industrial and consumer products, including vulcanization accelerators, corrosion inhibitors, fungicides, herbicides, algicides, and ultraviolet (UV) light stabilizers. Several benzothiazole derivatives are used commercially, and widespread use of these chemicals has led to ubiquitous occurrence in diverse environmental compartments. BTs have been reported to be dermal sensitizers, respiratory tract irritants, endocrine disruptors, carcinogens, and genotoxicants. This article reviews occurrence and fate of a select group of BTs in the environment, as well as human exposure and toxicity. BTs have frequently been found in various environmental matrices at concentrations ranging from sub-ng/L (surface water) to several tens of μg/g (indoor dust). The use of BTs in a number of consumer products, especially in rubber products, has resulted in widespread human exposure. BTs undergo chemical, biological, and photolytic degradation in the environment, creating several transformation products. Of these, 2-thiocyanomethylthio-benzothiazole (2-SCNMeS-BTH) has been shown to be the most toxic. Epidemiological studies have shown excess risks of cancers, including bladder cancer, lung cancer, and leukemia, among rubber factory workers, particularly those exposed to 2-mercapto-benzothiazole (2-SH-BTH). Human exposure to BTs continues to be a concern.

  7. Does a concomitant exposure to lead influence unfavorably the naphthalene subchronic toxicity and toxicokinetics?

    Science.gov (United States)

    Katsnelson, Boris A; Minigaliyeva, Ilzira A; Degtyareva, Tamara D; Privalova, Larisa I; Beresneva, Tatyana A

    2014-01-01

    Rats were given 20 times during 40 d either naphthalene per gavage or the same and lead acetate intraperitoneally in single doses corresponding to 5% of the respective 50% lethal doses. The concomitant exposure to lead not only added some typical indicators of lead toxicity to the moderate naphthalene intoxication picture but also exaggerated some less specific indices for intoxication. However, a number of such indices testified to attenuation of naphthalene's adverse effects under the impact of lead. Lead also lowered urinary excretion of both total and conjugated naphthalene, while the free- to total naphthalene ratio in urine sharply increased. These results corroborate implicitly the initial hypothesis that lead, being an inhibitor of cytochrome P450, hinders phase I of the naphthalene biotransformation and, thus, the formation of derivates which can be more toxic but are capable of entering into reactions of conjugation with resulting detoxication and elimination of naphthalene from the body. © 2013 SETAC.

  8. [Risk assessment and risk control for occupational exposure to chemical toxicants from an isophorone nitrile device].

    Science.gov (United States)

    Wang, Dejun; Fu, Xiaokuan; Kong, Fanling; Sui, Shaofeng; Jiang, Yuanyuan; Du, Yinglin; Zhou, Jingyang

    2014-06-01

    Risk assessment and risk control for occupational exposure to chemical toxicants were performed on an isophorone nitrile device with an annual production of 5,000 tons, based on improved Singaporean semi-quantitative risk assessment method, with consideration of actual situation in China and in the present project. With the use of engineering analysis and identification of occupational hazards in the improved Singaporean semi-quantitative risk assessment method, hazard rating (HR) and risk assessment were performed on chemical toxicants from an isophorone nitrile device with an annual production of 5,000 tons. The chemical toxicants in the isophorone nitrile device were mainly isophorone, hydrocyanic acid, methanol, phosphoric acid, sodium hydroxide, and sodium cyanide; the HR values were mild hazard (2), extreme hazard (5), mild hazard (2), mild hazard (2), moderate hazard (3), and extreme hazard (5), respectively, and the corresponding exposure rating (ER) values were 2.09, 2.72, 2.76, 1.68, 2.0, and 1.59, respectively. The risk of chemical toxicants in this project was assessed according to the formula Risk = [HR×ER](1/2). Hydrocyanic acid was determined as high risk, sodium hydroxide and sodium cyanide as medium risk, and isophorone, methanol, and phosphoric acid as low risk. Priority in handling of risks was determined by risk rating. The table of risk control measure was established for pre-assessment of occupational hazards. With risk assessment in this study, we concluded that the isophorone nitrile device with 5,000 ton annual production was a high-occupational hazard device. This device is a project of extreme occupational hazard. The improved Singaporean semi-quantitative risk assessment method is a scientific and applicable method, and is especially suitable for pre-evaluation of on-site project with no analogy.

  9. Modeling time-dependent toxicity to aquatic organisms from pulsed exposure of PAHs in urban road runoff

    International Nuclear Information System (INIS)

    Zhang Wei; Ye Youbin; Tong Yindong; Ou Langbo; Hu Dan; Wang Xuejun

    2011-01-01

    Understanding of the magnitude of urban runoff toxicity to aquatic organisms is important for effective management of runoff quality. In this paper, the aquatic toxicity of polycyclic aromatic hydrocarbons (PAHs) in urban road runoff was evaluated through a damage assessment model. Mortality probability of the organisms representative in aquatic environment was calculated using the monitored PAHs concentration in road runoff. The result showed that the toxicity of runoff in spring was higher than those in summer. Analysis of the time-dependent toxicity of series of runoff water samples illustrated that the toxicity of runoff water in the final phase of a runoff event may be as high as those in the initial phase. Therefore, the storm runoff treatment systems or strategies designed for capture and treatment of the initial portion of runoff may be inappropriate for control of runoff toxicity. - Research highlights: → Toxicity resulting from realistic exposure patterns of urban runoff is evaluated. → Toxicity of runoff water in the final phase is as high as the initial phase. → Treatment of the initial runoff portion is inappropriate to abate runoff toxicity. - Toxicity to aquatic organisms after sequential pulsed exposure to PAHs in urban road runoff is evaluated.

  10. Toxic metals in tissues of fishes from the Black Sea and associated human health risk exposure.

    Science.gov (United States)

    Plavan, Gabriel; Jitar, Oana; Teodosiu, Carmen; Nicoara, Mircea; Micu, Dragos; Strungaru, Stefan-Adrian

    2017-03-01

    The anthropogenic activities in the Black Sea area are responsible for toxic metal contamination of sea food products. In this study, several toxic metals: cadmium, lead, nickel, chromium, and copper were quantified in different tissues (digestive tract, muscle, skeleton, skin) of nine fish species (Neogobius melanostomus, Belone belone, Solea solea, Trachurus mediterraneus ponticus, Sardina pilchardus, Engraulis encrasicolus, Pomatomus saltatrix, Sprattus sprattus, Scorpaena porcus) by using atomic absorption spectrometer with a high-resolution continuum source and graphite furnace technique (HR-CS GF-AAS), and the risk of fish meat consumption by the young human population was evaluated. These metals are used in high amounts in industries located near the coastline such as shipyard construction and industrial plants. Toxic metal accumulation depends on fish feeding behavior, abiotic conditions, metal chemistry, and animal physiology. For instance, cadmium was measured in the muscle of the investigated species and average values of 0.0008-0.0338 mg kg -1 were obtained. The lowest average value of this metal was measured at benthic species N. melanostomus and the highest at the pelagic predator T. mediterraneus ponticus. Generally, the highest metal concentration was measured in the digestive tract that has the role of biofilter for these contaminants. The risk of contamination is significantly reduced by avoiding the consumption of certain fish tissues (digestive tract and skin for copper and skeleton for nickel). An estimation of the dietary metal intake to young consumers was realized for each of the studied species of fish from Romanian, Bulgarian, and Turkish waters, during the period 2001-2014 in order to evaluate the risks of chronic exposure in time due to metal toxicity. This estimation is important for the prevention of chronic exposure due to metal toxicity. Food exposure to studied metals showed a negative trend for Romania, Turkey, and Bulgaria based

  11. Gene networks and toxicity pathways induced by acute cadmium exposure in adult largemouth bass (Micropterus salmoides)

    International Nuclear Information System (INIS)

    Mehinto, Alvine C.; Prucha, Melinda S.; Colli-Dula, Reyna C.; Kroll, Kevin J.; Lavelle, Candice M.; Barber, David S.; Vulpe, Christopher D.; Denslow, Nancy D.

    2014-01-01

    Highlights: • Low-level acute cadmium exposure elicited tissue-specific gene expression changes. • Molecular initiating events included oxidative stress and disruption of DNA repair. • Metallothionein, a marker of metal exposure, was not significantly affected. • We report effects of cadmium on cholesterol metabolism and steroid synthesis. • Diabetic complications and impaired reproduction are potential adverse outcomes. - Abstract: Cadmium is a heavy metal that can accumulate to toxic levels in the environment leading to detrimental effects in animals and humans including kidney, liver and lung injuries. Using a transcriptomics approach, genes and cellular pathways affected by a low dose of cadmium were investigated. Adult largemouth bass were intraperitoneally injected with 20 μg/kg of cadmium chloride (mean exposure level – 2.6 μg of cadmium per fish) and microarray analyses were conducted in the liver and testis 48 h after injection. Transcriptomic profiles identified in response to cadmium exposure were tissue-specific with the most differential expression changes found in the liver tissues, which also contained much higher levels of cadmium than the testis. Acute exposure to a low dose of cadmium induced oxidative stress response and oxidative damage pathways in the liver. The mRNA levels of antioxidants such as catalase increased and numerous transcripts related to DNA damage and DNA repair were significantly altered. Hepatic mRNA levels of metallothionein, a molecular marker of metal exposure, did not increase significantly after 48 h exposure. Carbohydrate metabolic pathways were also disrupted with hepatic transcripts such as UDP-glucose, pyrophosphorylase 2, and sorbitol dehydrogenase highly induced. Both tissues exhibited a disruption of steroid signaling pathways. In the testis, estrogen receptor beta and transcripts linked to cholesterol metabolism were suppressed. On the contrary, genes involved in cholesterol metabolism were highly

  12. Gene networks and toxicity pathways induced by acute cadmium exposure in adult largemouth bass (Micropterus salmoides)

    Energy Technology Data Exchange (ETDEWEB)

    Mehinto, Alvine C., E-mail: alvinam@sccwrp.org [Southern California Coastal Water Research Project, Costa Mesa, CA 92626 (United States); Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Prucha, Melinda S. [Department of Human Genetics, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322 (United States); Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Colli-Dula, Reyna C.; Kroll, Kevin J.; Lavelle, Candice M.; Barber, David S. [Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Vulpe, Christopher D. [Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720 (United States); Denslow, Nancy D. [Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States)

    2014-07-01

    Highlights: • Low-level acute cadmium exposure elicited tissue-specific gene expression changes. • Molecular initiating events included oxidative stress and disruption of DNA repair. • Metallothionein, a marker of metal exposure, was not significantly affected. • We report effects of cadmium on cholesterol metabolism and steroid synthesis. • Diabetic complications and impaired reproduction are potential adverse outcomes. - Abstract: Cadmium is a heavy metal that can accumulate to toxic levels in the environment leading to detrimental effects in animals and humans including kidney, liver and lung injuries. Using a transcriptomics approach, genes and cellular pathways affected by a low dose of cadmium were investigated. Adult largemouth bass were intraperitoneally injected with 20 μg/kg of cadmium chloride (mean exposure level – 2.6 μg of cadmium per fish) and microarray analyses were conducted in the liver and testis 48 h after injection. Transcriptomic profiles identified in response to cadmium exposure were tissue-specific with the most differential expression changes found in the liver tissues, which also contained much higher levels of cadmium than the testis. Acute exposure to a low dose of cadmium induced oxidative stress response and oxidative damage pathways in the liver. The mRNA levels of antioxidants such as catalase increased and numerous transcripts related to DNA damage and DNA repair were significantly altered. Hepatic mRNA levels of metallothionein, a molecular marker of metal exposure, did not increase significantly after 48 h exposure. Carbohydrate metabolic pathways were also disrupted with hepatic transcripts such as UDP-glucose, pyrophosphorylase 2, and sorbitol dehydrogenase highly induced. Both tissues exhibited a disruption of steroid signaling pathways. In the testis, estrogen receptor beta and transcripts linked to cholesterol metabolism were suppressed. On the contrary, genes involved in cholesterol metabolism were highly

  13. Impact of repeated exposure on toxicity of perchloroethylene in Swiss Webster mice

    International Nuclear Information System (INIS)

    Philip, Binu K.; Mumtaz, Moiz M.; Latendresse, John R.; Mehendale, Harihara M.

    2007-01-01

    The aim was to study the subchronic toxicity of perchloroethylene (Perc) by measuring injury and repair in liver and kidney in relation to disposition of Perc and its major metabolites. Male SW mice (25-29 g) were given three dose levels of Perc (150, 500, and 1000 mg/kg day) via aqueous gavage for 30 days. Tissue injury was measured during the dosing regimen (0, 1, 7, 14, and 30 days) and over a time course of 24-96 h after the last dose (30 days). Perc produced significant liver injury (ALT) after single day exposure to all three doses. Liver injury was mild to moderate and regressed following repeated exposure for 30 days. Subchronic Perc exposure induced neither kidney injury nor dysfunction during the entire time course as evidenced by normal renal histology and BUN. TCA was the major metabolite detected in blood, liver, and kidney. Traces of DCA were also detected in blood at initial time points after single day exposure. With single day exposure, metabolism of Perc to TCA was saturated with all three doses. AUC/dose ratio for TCA was significantly decreased with a concomitant increase in AUC/dose of Perc levels in liver and kidney after 30 days as compared to 1 day exposures, indicating inhibition of metabolism upon repeated exposure to Perc. Hepatic CYP2E1 expression and activity were unchanged indicating that CYP2E1 is not the critical enzyme inhibited. Hepatic CYP4A expression, measured as a marker of peroxisome proliferation was increased transiently only on day 7 with the high dose, but was unchanged at later time points. Liver tissue repair peaked at 7 days, with all three doses and was sustained after medium and high dose exposure for 14 days. These data indicate that subchronic Perc exposure via aqueous gavage does not induce nephrotoxicity and sustained hepatotoxicity suggesting adaptive hepatic repair mechanisms. Enzymes other than CYP2E1, involved in the metabolism of Perc may play a critical role in the metabolism of Perc upon subchronic exposure

  14. Bioaccumulation and toxicity of selenium during a life-cycle exposure with desert pupfish (Cyprinodon macularius)

    Science.gov (United States)

    Besser, John M.; Brumbaugh, William G.; Papoulias, Diana M.; Ivey, Chris D.; Kunz, James L.; Annis, Mandy; Ingersoll, Christopher G.

    2012-01-01

    Populations of desert pupfish (Cyprinodon macularius; pupfish), a federally-listed endangered species, inhabit irrigation drains in the Imperial Valley agricultural area of southern California. These drains have varying degrees of selenium (Se) contamination of water, sediment, and aquatic biota. Published Se toxicity studies suggest that these levels of Se contamination may pose risk of chronic toxicity to Se-sensitive fish, but until recently there have been no studies of the chronic toxicity of Se to desert pupfish.A life-cycle Se exposure with pupfish was conducted to estimate dietary and tissue thresholds for toxic effects of Se on all life stages. The dietary exposure was based on live oligochaete worms (Lumbriculus variegatus) dosed with Se by a laboratory food chain based on selenized yeast. Oligochaetes readily accumulated Se from mixtures of selenized and control yeasts. The protocol for dosing oligochaetes for pupfish feeding studies included long-term (at least 28 days) feeding of a low-ration of yeast mixtures to large batches of oligochaetes. Oligochaetes were dosed at five Se levels in a 50-percent dilution series. Pupfish were simultaneously fed Se-dosed oligochaetes and exposed to a series of Se concentrations in water (consisting of 85 percent selenate and 15 percent selenite) to produce exposures that were consistent with Se concentrations and speciation in pupfish habitats. The nutritional characteristics of oligochaete diets were consistent across the range of oligochaete Se concentrations tested.The life-cycle exposure started with laboratory-cultured juvenile pupfish that were exposed to Se through sexual maturation and reproduction (150 days; F0 exposure). The Se exposure continued with eggs, larvae, and juveniles produced by Se-exposed parents (79 days; F1 exposure). Selenium exposure (water and diets), Se bioaccumulation (whole-body and eggs), and toxicity endpoints (juvenile and adult survival and growth; egg production and hatching

  15. Dosimetry of the Occupational Exposure Personnel and not exposure of the INNSZ; Dosimetria del Personal Ocupacionalmente Expuesto (POE) y no expuesto del INNSZ

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz J, A [Departamento de Medicina Nuclear, Instituto nacional de la nutricion Salvador Zubiran, Mexico D.F. C.P. 14100 (Mexico)

    1999-07-01

    In this work, was measured the equivalent dose of all the personnel of Nuclear medicine and personnel of the Institute which by its activities remain in the Department, by time determined, through thermoluminescent dosemeters and the results were that the personnel presents variable equivalent dose and it is proportional to the time and radionuclide type which use for their work. By this it is allowed to secure what the work watched with respect to radiological protection to fulfil with the International Standards standing for personnel in the Institute. (Author)

  16. Overview of the Benzene and Other Toxics Exposure (BEE-TEX) Field Study.

    Science.gov (United States)

    Olaguer, Eduardo P

    2015-01-01

    The Benzene and other Toxics Exposure (BEE-TEX) field study was an experimental campaign designed to demonstrate novel methods for measuring ambient concentrations of hazardous air pollutants (HAPs) in real time and to attribute these concentrations to quantified releases from specific emission points in industrial facilities while operating outside facility fence lines. BEE-TEX was conducted in February 2015 at three neighboring communities in the Houston Ship Channel of Texas, where a large number of petrochemical facilities are concentrated. The novel technologies deployed during BEE-TEX included: (1) tomographic remote sensing based on differential optical absorption spectroscopy; (2) real-time broadcasting of ambient air monitoring data over the World Wide Web; (3) real-time source attribution and quantification of HAP emissions based on either tomographic or mobile measurement platforms; and (4) the use of cultured human lung cells in vitro as portable indicators of HAP exposure.

  17. Can chronic exposure to imidacloprid, clothianidin, and thiamethoxam mixtures exert greater than additive toxicity in Chironomus dilutus?

    Science.gov (United States)

    Maloney, E M; Morrissey, C A; Headley, J V; Peru, K M; Liber, K

    2018-07-30

    Widespread agricultural use of neonicotinoid insecticides has resulted in frequent detection of mixtures of these compounds in global surface waters. Recent evidence suggests that neonicotinoid mixtures can elicit synergistic toxicity in aquatic insects under acute exposure conditions, however this has not been validated for longer exposures more commonly encountered in the environment. Therefore, we aimed to characterize the chronic (28-day) toxicity of imidacloprid, clothianidin, and thiamethoxam mixtures under different doses and mixture ratios to determine if the assumption of synergistic toxicity would hold under more environmentally realistic exposure settings. The sensitive aquatic insect Chironomus dilutus was used as a representative test species, and successful emergence was used as a chronic endpoint. Applying the MIXTOX modeling approach, predictive parametric models were fitted using single-compound toxicity data and statistically compared to observed toxicity in subsequent mixture tests. Imidacloprid-clothianidin, clothianidin-thiamethoxam and imidacloprid-clothianidin-thiamethoxam mixtures did not significantly deviate from concentration-additive toxicity. However, the cumulative toxicity of the imidacloprid-thiamethoxam mixture deviated from the concentration-additive reference model, displaying dose-ratio dependent synergism and resulting in up to a 10% greater reduction in emergence from that predicted by concentration addition. Furthermore, exposure to select neonicotinoid mixtures above 1.0 toxic unit tended to shift sex-ratios toward more male-dominated populations. Results indicate that, similar to acute exposures, the general assumption of joint additivity cannot adequately describe chronic cumulative toxicity of all neonicotinoid mixtures. Indeed, our observations of weak synergism and sex-ratio shifts elicited by some mixture combinations should be considered in water quality guideline development and environmental risk assessment practices

  18. Exposure to daily trauma: The experiences and coping mechanism of Emergency Medical Personnel. A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Llizane Minnie

    2015-03-01

    Conclusion: EMS personnel are exposed to critical incidents on a daily basis. Commonly used emotion-focused coping mechanisms are not effective in long-term coping. A key recommendation emanating from this finding is that integrated intervention programmes are needed to assist EMS personnel working in this sustained high-stress environment. The findings can assist health care educators in the design of co-curricular activities intended to help in the development of resilience and the psychological wellbeing of EMS personnel. Policy makers and EMS managers may find the results useful as they evaluate the effectiveness of their current debriefing and support structures.

  19. Toxicity of nitrogenous fertilizers to eggs of snapping turtles (Chelydra serpentina) in field and laboratory exposures.

    Science.gov (United States)

    de Solla, Shane Raymond; Martin, Pamela Anne

    2007-09-01

    Many reptiles oviposit in soil of agricultural landscapes. We evaluated the toxicity of two commonly used nitrogenous fertilizers, urea and ammonium nitrate, on the survivorship of exposed snapping turtle (Chelydra serpentina) eggs. Eggs were incubated in a community garden plot in which urea was applied to the soil at realistic rates of up to 200 kg/ha in 2004, and ammonium nitrate was applied at rates of up to 2,000 kg/ha in 2005. Otherwise, the eggs were unmanipulated and were subject to ambient temperature and weather conditions. Eggs were also exposed in the laboratory in covered bins so as to minimize loss of nitrogenous compounds through volatilization or leaching from the soil. Neither urea nor ammonium nitrate had any impact on hatching success or development when exposed in the garden plot, despite overt toxicity of ammonium nitrate to endogenous plants. Both laboratory exposures resulted in reduced hatching success, lower body mass at hatching, and reduced posthatching survival compared to controls. The lack of toxicity of these fertilizers in the field was probably due to leaching in the soil and through atmospheric loss. In general, we conclude that nitrogenous fertilizers probably have little direct impacts on turtle eggs deposited in agricultural landscapes.

  20. Isotopically modified silver nanoparticles to assess nanosilver bioavailability and toxicity at environmentally relevant exposures

    Science.gov (United States)

    Croteau, Marie-Noële; Dybowska, Agnieszka D.; Luoma, Samuel N.; Misra, Superb K.; Valsami-Jones, Eugenia

    2014-01-01

    A major challenge in understanding the environmental implications of nanotechnology lies in studying nanoparticle uptake in organisms at environmentally realistic exposure concentrations. Typically, high exposure concentrations are needed to trigger measurable effects and to detect accumulation above background. But application of tracer techniques can overcome these limitations. Here we synthesised, for the first time, citrate-coated Ag nanoparticles using Ag that was 99.7 % 109Ag. In addition to conducting reactivity and dissolution studies, we assessed the bioavailability and toxicity of these isotopically modified Ag nanoparticles (109Ag NPs) to a freshwater snail under conditions typical of nature. We showed that accumulation of 109Ag from 109Ag NPs is detectable in the tissues of Lymnaea stagnalis after 24-h exposure to aqueous concentrations as low as 6 ng L–1 as well as after 3 h of dietary exposure to concentrations as low as 0.07 μg g–1. Silver uptake from unlabelled Ag NPs would not have been detected under similar exposure conditions. Uptake rates of 109Ag from 109Ag NPs mixed with food or dispersed in water were largely linear over a wide range of concentrations. Particle dissolution was most important at low waterborne concentrations. We estimated that 70 % of the bioaccumulated 109Ag concentration in L. stagnalis at exposures –1 originated from the newly solubilised Ag. Above this concentration, we predicted that 80 % of the bioaccumulated 109Ag concentration originated from the 109Ag NPs. It was not clear if agglomeration had a major influence on uptake rates.

  1. St. John's wort significantly increased the systemic exposure and toxicity of methotrexate in rats

    International Nuclear Information System (INIS)

    Yang, Shih-Ying; Juang, Shin-Hun; Tsai, Shang-Yuan; Chao, Pei-Dawn Lee; Hou, Yu-Chi

    2012-01-01

    St. John's wort (SJW, Hypericum perforatum) is one of the popular nutraceuticals for treating depression. Methotrexate (MTX) is an immunosuppressant with narrow therapeutic window. This study investigated the effect of SJW on MTX pharmacokinetics in rats. Rats were orally given MTX alone and coadministered with 300 and 150 mg/kg of SJW, and 25 mg/kg of diclofenac, respectively. Blood was withdrawn at specific time points and serum MTX concentrations were assayed by a specific monoclonal fluorescence polarization immunoassay method. The results showed that 300 mg/kg of SJW significantly increased the AUC 0−t and C max of MTX by 163% and 60%, respectively, and 150 mg/kg of SJW significantly increased the AUC 0−t of MTX by 55%. In addition, diclofenac enhanced the C max of MTX by 110%. The mortality of rats treated with SJW was higher than that of controls. In conclusion, coadministration of SJW significantly increased the systemic exposure and toxicity of MTX. The combined use of MTX with SJW would need to be with caution. -- Highlights: ► St. John's wort significantly increased the AUC 0−t and C max of methotrexate. ► Coadministration of St. John's wort increased the exposure and toxicity of methotrexate. ► The combined use of methotrexate with St. John's wort will need to be with caution.

  2. A novel approach reveals that zinc oxide nanoparticles are bioavailable and toxic after dietary exposures

    Science.gov (United States)

    Croteau, M.-N.; Dybowska, A.D.; Luoma, S.N.; Valsami-Jones, E.

    2011-01-01

    If engineered nanomaterials are released into the environment, some are likely to end up associated with the food of animals due to aggregation and sorption processes. However, few studies have considered dietary exposure of nanomaterials. Here we show that zinc (Zn) from isotopically modified 67ZnO particles is efficiently assimilated by freshwater snails when ingested with food. The 67Zn from nano-sized 67ZnO appears as bioavailable as 67Zn internalized by diatoms. Apparent agglomeration of the zinc oxide (ZnO) particles did not reduce bioavailability, nor preclude toxicity. In the diet, ZnO nanoparticles damage digestion: snails ate less, defecated less and inefficiently processed the ingested food when exposed to high concentrations of ZnO. It was not clear whether the toxicity was due to the high Zn dose achieved with nanoparticles or to the ZnO nanoparticles themselves. Further study of exposure from nanoparticles in food would greatly benefit assessment of ecological and human health risks. ?? 2011 Informa UK, Ltd.

  3. Toxicity assessment of sodium fluoride in Drosophila melanogaster after chronic sub-lethal exposure.

    Science.gov (United States)

    Dutta, Moumita; Rajak, Prem; Khatun, Salma; Roy, Sumedha

    2017-01-01

    Sodium fluoride (NaF), one of the most frequently used fluoride compound is composed of Na + and F - . Apart from its use in water fluoridation, NaF also acts as a major component for different dental products like toothpastes, gels and mouth rinses etc. The present study was carried out to explore the toxic impact of chronic NaF exposure on a non-target organism, Drosophila melanogaster. The larvae exposed to different concentrations of NaF through food showed a significant increase in HSP70 expression both qualitatively and quantitatively. The altered tail length and tail intensity in Comet assay validate the increased DNA damage in treated larvae. The activity of AChE, oxidative stress marker enzymes, phase I and phase II detoxifying enzymes were found to be significantly inhibited in the treated larvae when compared to control though there was no evidence of dose dependent change in each case. The alterations in the mentioned parameters can be due to increased body Fluoride ion (F - ) concentration since the analysis with ion electrode analyzer revealed that F - concentration increased significantly with NaF treatment. Hence, the results suggest that D. melanogaster manifest prominent toxic response when subjected to chronic exposure to sub-lethal NaF concentrations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Modeling physiological processes that relate toxicant exposure and bacterial population dynamics.

    Directory of Open Access Journals (Sweden)

    Tin Klanjscek

    Full Text Available Quantifying effects of toxicant exposure on metabolic processes is crucial to predicting microbial growth patterns in different environments. Mechanistic models, such as those based on Dynamic Energy Budget (DEB theory, can link physiological processes to microbial growth.Here we expand the DEB framework to include explicit consideration of the role of reactive oxygen species (ROS. Extensions considered are: (i additional terms in the equation for the "hazard rate" that quantifies mortality risk; (ii a variable representing environmental degradation; (iii a mechanistic description of toxic effects linked to increase in ROS production and aging acceleration, and to non-competitive inhibition of transport channels; (iv a new representation of the "lag time" based on energy required for acclimation. We estimate model parameters using calibrated Pseudomonas aeruginosa optical density growth data for seven levels of cadmium exposure. The model reproduces growth patterns for all treatments with a single common parameter set, and bacterial growth for treatments of up to 150 mg(Cd/L can be predicted reasonably well using parameters estimated from cadmium treatments of 20 mg(Cd/L and lower. Our approach is an important step towards connecting levels of biological organization in ecotoxicology. The presented model reveals possible connections between processes that are not obvious from purely empirical considerations, enables validation and hypothesis testing by creating testable predictions, and identifies research required to further develop the theory.

  5. Comparative toxicity of low dose tributyltin chloride on serum, liver, lung and kidney following subchronic exposure.

    Science.gov (United States)

    Mitra, Sumonto; Gera, Ruchi; Singh, Vikas; Khandelwal, Shashi

    2014-02-01

    Tributyltin (TBT) pollution is rampant worldwide and is a growing threat due to its bio-accumulative property. Isolated studies of TBT toxicity on different organs are available but consolidated information is greatly lacking. We planned this study to delineate the effect of subchronic (1 month) exposure to low dose TBT-chloride (TBTC) (1 and 5 mg/kg) in male Wistar rats. Total tin concentration was found to be significantly increased in liver, kidney and blood, and marginally in lungs. Organo-somatic indices were seen to be altered with little effect on serum biochemical markers (liver and kidney function, and general parameters). Reactive oxygen species but not lipid peroxidation content was observed to be significantly elevated both in the tissues and serum. TBTC was found to act as a hyperlipidemic agent and it also affected heme biosynthetic pathway. Hematological analysis showed that TBTC exposure resulted in minor alterations in RBC parameters. Histological studies demonstrated marked tissue damage in all the 3 organs. Calcium inhibitors (BAPTA-AM, EGTA) and antioxidants (NAC, C-PC) significantly restored TBTC induced loss in cell viability, under ex-vivo conditions. Antioxidants were evidently more efficient in comparison to the calcium inhibitors, implying major role of oxidative stress pathways in TBTC toxicity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Exposure to Alumina Nanoparticles in Female Mice During Pregnancy Induces Neurodevelopmental Toxicity in the Offspring.

    Science.gov (United States)

    Zhang, Qinli; Ding, Yong; He, Kaihong; Li, Huan; Gao, Fuping; Moehling, Taylor J; Wu, Xiaohong; Duncan, Jeremy; Niu, Qiao

    2018-01-01

    Alumina nanoparticles (AlNP) have been shown to accumulate in organs and penetrate biological barriers which lead to toxic effects in many organ systems. However, it is not known whether AlNP exposure to female mice during pregnancy can affect the development of the central nervous system or induce neurodevelopmental toxicity in the offspring. The present study aims to examine the effect of AlNP on neurodevelopment and associated underlying mechanism. ICR strain adult female mice were randomly divided into four groups, which were treated with normal saline (control), 10 μm particle size of alumina (bulk-Al), and 50 and 13 nm AlNP during entire pregnancy period. Aluminum contents in the hippocampus of newborns were measured and neurodevelopmental behaviors were tracked in the offspring from birth to 1 month of age. Furthermore, oxidative stress and neurotransmitter levels were measured in the cerebral cortex of the adolescents. Our results showed that aluminum contents in the hippocampus of newborns in AlNP-treated groups were significantly higher than those in bulk-Al and controls. Moreover, the offspring delivered by AlNP-treated female mice displayed stunted neurodevelopmental behaviors. Finally, the offspring of AlNP-treated mice demonstrated significantly increased anxiety-like behavior with impaired learning and memory performance at 1 month of age. The underlying mechanism could be related to increased oxidative stress and decreased neurotransmitter levels in the cerebral cortex. We therefore conclude that AlNP exposure of female mice during pregnancy can induce neurodevelopmental toxicity in offspring.

  7. Toxicity of silicon carbide nanowires to sediment-dwelling invertebrates in water or sediment exposures

    Science.gov (United States)

    Mwangi, Joseph N.; Wang, Ning; Ritts, Andrew; Kunz, James L.; Ingersoll, Christopher G.; Li, Hao; Deng, Baolin

    2011-01-01

    Silicon carbide nanowires (SiCNW) are insoluble in water. When released into an aquatic environment, SiCNW would likely accumulate in sediment. The objective of this study was to assess the toxicity of SiCNW to four freshwater sediment-dwelling organisms: amphipods (Hyalella azteca), midges (Chironomus dilutus), oligochaetes (Lumbriculus variegatus), and mussels (Lampsilis siliquoidea). Amphipods were exposed to either sonicated or nonsonicated SiCNW in water (1.0 g/L) for 48 h. Midges, mussels, and oligochaetes were exposed only to sonicated SiCNW in water for 96 h. In addition, amphipods were exposed to sonicated SiCNW in whole sediment for 10 d (44% SiCNW on dry wt basis). Mean 48-h survival of amphipods exposed to nonsonicated SiCNW in water was not significantly different from the control, whereas mean survival of amphipods exposed to sonicated SiCNW in two 48-h exposures (0 or 15% survival) was significantly different from the control (90 or 98% survival). In contrast, no effect of sonicated SiCNW was observed on survival of midges, mussels, or oligochaetes. Survival of amphipods was not significantly reduced in 10-d exposures to sonicated SiCNW either mixed in the sediment or layered on the sediment surface. However, significant reduction in amphipod biomass was observed with the SiCNW either mixed in sediment or layered on the sediment surface, and the reduction was more pronounced for SiCNW layered on the sediment. These results indicated that, under the experimental conditions, nonsonicated SiCNW in water were not acutely toxic to amphipods, sonicated SiCNW in water were acutely toxic to the amphipods, but not to other organisms tested, and sonicated SiCNW in sediment affected the growth but not the survival of amphipods.

  8. Emission of parasitic X-rays from military radar transmitters and exposure of personnel: towards a retrospective assessment

    Energy Technology Data Exchange (ETDEWEB)

    Schirmer, A. [Arbeitsgruppe Aufklarung der Arbeitsplatzverhaltnisse Radar, Wehrbereichsverwaltung Nord, Bundeswehr, Munster (Germany)

    2006-07-01

    An overview of the investigation of parasitic-X-ray (Bremsstrahlung) from high-voltage electron vacuum tubes in military radar transmitters is given. From technical inspection, data evaluation and measurements maximum dose rates for work places of the personnel are calculated. With dedicated workplace surveys the maximum dose H{sup *}(10) per month for the personnel is estimated for the entire time of use of the different radar sets. (author)

  9. Emission of parasitic X-rays from military radar transmitters and exposure of personnel: towards a retrospective assessment

    International Nuclear Information System (INIS)

    Schirmer, A.

    2006-01-01

    An overview of the investigation of parasitic-X-ray (Bremsstrahlung) from high-voltage electron vacuum tubes in military radar transmitters is given. From technical inspection, data evaluation and measurements maximum dose rates for work places of the personnel are calculated. With dedicated workplace surveys the maximum dose H * (10) per month for the personnel is estimated for the entire time of use of the different radar sets. (author)

  10. Toxicity assessment of zebrafish following exposure to CdTe QDs

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei, E-mail: wzhang@ecust.edu.cn [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237 (China); School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237 (China); Lin, Kuangfei, E-mail: kflin@ecust.edu.cn [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237 (China); School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237 (China); Miao, Youna [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237 (China); School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237 (China); Dong, Qiaoxiang; Huang, Changjiang; Wang, Huili [Zhejiang Provincial Key Lab for Technology and Application of Model Organisms, Wenzhou Medical College, Wenzhou 325035 (China); Guo, Meijin [State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237 (China); Cui, Xinhong [Shanghai Institute of Landscape Gardening, Shanghai 200233 (China)

    2012-04-30

    Highlights: Black-Right-Pointing-Pointer The LC{sub 50} of TGA-CdTe for zebrafish at 120 hpf was 185.9 nM. Black-Right-Pointing-Pointer Zebrafish exposed to TGA-CdTe resulted in lower hatch rate and more malformation. Black-Right-Pointing-Pointer Body length and heart beat of zebrafish declined after exposure to TGA-CdTe. Black-Right-Pointing-Pointer Larvae exposure to TGA-CdTe elicited a higher basal swimming rate. Black-Right-Pointing-Pointer Abnormal vascular of FLI-1 transgenic zebrafish larvae exposed to TGA-CdTe occurred. - Abstract: CdTe quantum dots (QDs) are nanocrystals of unique composition and properties that have found many new commercial applications; therefore, their potential toxicity to aquatic organisms has become a hot research topic. The lab study was performed to determine the developmental and behavioral toxicities to zebrafish under continuous exposure to low concentrations of CdTe QDs (1-400 nM) coated with thioglycolic acid (TGA). The results show: (1) the 120 h LC{sub 50} of 185.9 nM, (2) the lower hatch rate and body length, more malformations, and less heart beat and swimming speed of the exposed zebrafish, (3) the brief burst and a higher basal swimming rate of the exposed zebrafish larvae during a rapid transition from light-to-dark, and (4) the vascular hyperplasia, vascular bifurcation, vascular crossing and turbulence of the exposed FLI-1 transgenic zebrafish larvae.

  11. In situ exposures using caged organisms: a multi-compartment approach to detect aquatic toxicity and bioaccumulation

    International Nuclear Information System (INIS)

    Burton, G. Allen; Greenberg, Marc S.; Rowland, Carolyn D.; Irvine, Cameron A.; Lavoie, Daniel R.; Brooker, John A.; Moore, Laurie; Raymer, Delia F.N.; McWilliam, Ruth A.

    2005-01-01

    An in situ toxicity and bioaccumulation assessment approach is described to assess stressor exposure and effects in surface waters (low and high flow), the sediment-water interface, surficial sediments and pore waters (including groundwater upwellings). This approach can be used for exposing species, representing major functional and taxonomic groups. Pimephales promelas, Daphnia magna, Ceriodaphnia dubia, Hyalella azteca, Hyalella sp., Chironomus tentans, Lumbriculus variegatus, Hydra attenuatta, Hexagenia sp. and Baetis tibialis were successfully used to measure effects on survival, growth, feeding, and/or uptake. Stressors identified included chemical toxicants, suspended solids, photo-induced toxicity, indigenous predators, and flow. Responses varied between laboratory and in situ exposures in many cases and were attributed to differing exposure dynamics and sample-processing artifacts. These in situ exposure approaches provide unique assessment information that is complementary to traditional laboratory-based toxicity and bioaccumulation testing and reduce the uncertainties of extrapolating from the laboratory to field responses. - In situ exposures provide unique information that is complementary to traditional lab-based toxicity results

  12. Role of oxidative stress in liver and kidney in uranium toxicity after chronic exposure

    International Nuclear Information System (INIS)

    Poisson - Moreau-De-Lizoreux, C.

    2013-01-01

    Uranium is a radioactive heavy metal found in the environment. Due to its natural presence and to civil and militaries activities, general population can be exposed to U throughout drinking water or contaminated food. The pro/anti-oxidative system is a defense system which is often implicated in case of acute exposure to U. The aim of this thesis is to study the role of the pro/anti-oxidative system after chronic exposure to U in the liver and the kidney. After chronic exposure of rats to different U concentrations, this radionuclide accumulated in the organs in proportion to U intake; until 6 μg.g -1 of kidney tissues. U is localized in nucleus of the proximal tubular cells of the kidney. No nephrotoxicity was described even for the higher U level in drinking water and a reinforcement of the pro/anti-oxidative system with an increase in glutathione is observed. The study of U internal contamination in Nrf2 deficient mice, a cytoprotective transcription factor involved in the anti-oxidative defense has been realized. U accumulate more in Nrf2 mice than in WT mice but the biologic effects of U on the pro/anti-oxidative system did not seem to implicate Nrf2. At the cell level, a correlation between U distribution in HepG2 cells and the biological effects on this system is observed after U exposure at low concentrations. Soluble distribution of U is observed in cell nucleus. The apparition of U precipitates is correlated to the establishment of the adaptive mechanisms overtime which are overwhelmed and lead to a cellular toxicity at higher U level. In conclusion, these results suggest that the reinforcement of pro/anti-oxidative system could be an adaptive mechanism after chronic exposure at low U concentration. (author) [fr

  13. Monitoring of the internal contamination of occupationally exposure personnel in services of nuclear medicine through the use of gamma cameras

    International Nuclear Information System (INIS)

    Teran, M.; Paolino, A.; Savio, E.; Hermida, J.C.; Dantas, B.M.

    2006-01-01

    The radionuclides incorporation can happen as a result of diverse activities; these include the work associated with the different stadiums of the nuclear fuel cycle, the use of radioactive sources in medicine, the scientific research, the agriculture and the industry. In Uruguay the main activities linked to the manipulation of open sources correspond those of Nuclear Medicine and from 2004, in the mark of the Project Arcal RLA 049 and being based on the Safety Guides of the IAEA it is implementing a program of internal monitoring in combined form the Nuclear Medicine Center of the Hospital of and the Radiochemistry class of the Faculty of Chemistry. In accordance with the publication of the ICRP 75 the emphasis of any monitoring program should be in the formal study of the doses in the workers to who are considered commendable of to receive in routine form an outstanding fraction of the dose limits or who work in areas where the exposures can be significant in the accident event. From April 2004, to the date has started a pilot plan by means of in that were established appropriate conditions of procedures and of safety in a reduced group of workers of the Nuclear Medicine area. In that period the first work limits, equipment adjustment, calibrations and registration systems were determined. The monitoring system implemented until the moment is carried out with a thyroid caption equipment. However these measurements are carried out in the university hospital embracing 40% of the involved workers of our country, with the purpose of reaching the covering of the biggest quantity of occupationally exposed personnel of private clinics. Also it was developed a new work proposal that allows to have an alternative measure method, in the event of not having the equipment habitually used. Among the conclusions of this work are that for the before exposed are considered the measure conditions but appropriate the following ones: Gamma Camera without collimator; Measurement

  14. Toxicity assessment of TiO{sub 2} nanoparticles in zebrafish embryos under different exposure conditions

    Energy Technology Data Exchange (ETDEWEB)

    Clemente, Z., E-mail: zairaclemente@yahoo.com.br [Laboratório de Ecotoxicologia e Biossegurança, Embrapa CNPMA, Jaguariúna, SP (Brazil); Programa de Pós-graduação em Biologia Funcional e Molecular, UNICAMP, Campinas, SP (Brazil); Castro, V.L.S.S. [Laboratório de Ecotoxicologia e Biossegurança, Embrapa CNPMA, Jaguariúna, SP (Brazil); Moura, M.A.M. [Laboratório da Ciência das Plantas Daninhas, Instituto Biológico, APTA/SAA, Campinas, SP (Brazil); Jonsson, C.M. [Laboratório de Ecotoxicologia e Biossegurança, Embrapa CNPMA, Jaguariúna, SP (Brazil); Fraceto, L.F. [Programa de Pós-graduação em Biologia Funcional e Molecular, UNICAMP, Campinas, SP (Brazil); Departamento de Engenharia Ambiental, UNESP, Sorocaba, SP (Brazil)

    2014-02-15

    Highlights: •Nano-TiO{sub 2} accelerated hatching of the larvae. •Exposure to anatase/rutile mixture under UV light altered the equilibrium and survival of the larvae. •Nano-TiO{sub 2} caused alterations in the activities of CAT and GST. -- Abstract: The popularity of TiO{sub 2} nanoparticles (nano-TiO{sub 2}) lies in their wide range of nanotechnological applications, together with low toxicity. Meanwhile, recent studies have shown that the photocatalytic properties of this material can result in alterations in their behavior in the environment, causing effects that have not yet been fully elucidated. The objective of this study was to evaluate the toxicity of two formulations of nano-TiO{sub 2} under different illumination conditions, using an experimental model coherent with the principle of the three Rs of alternative animal experimentation (reduction, refinement, and replacement). Embryos of the fish Danio rerio were exposed for 96 h to different concentrations of nano-TiO{sub 2} in the form of anatase (TA) or an anatase/rutile mixture (TM), under either visible light or a combination of visible and ultraviolet light (UV). The acute toxicity and sublethal parameters evaluated included survival rates, malformation, hatching, equilibrium, and overall length of the larvae, together with biochemical biomarkers (specific activities of catalase (CAT), glutathione S-transferase (GST), and acid phosphatase (AP)). Both TA and TM caused accelerated hatching of the larvae. Under UV irradiation, there was greater mortality of the larvae of the groups exposed to TM, compared to those exposed to TA. Exposure to TM under UV irradiation altered the equilibrium of the larvae. Alterations in the activities of CAT and GST were indicative of oxidative stress, although no clear dose-response relationship was observed. The effects of nano-TiO{sub 2} appeared to depend on both the type of formulation and the illumination condition. The findings contribute to elucidation of the

  15. Toxicity assessment of TiO2 nanoparticles in zebrafish embryos under different exposure conditions

    International Nuclear Information System (INIS)

    Clemente, Z.; Castro, V.L.S.S.; Moura, M.A.M.; Jonsson, C.M.; Fraceto, L.F.

    2014-01-01

    Highlights: •Nano-TiO 2 accelerated hatching of the larvae. •Exposure to anatase/rutile mixture under UV light altered the equilibrium and survival of the larvae. •Nano-TiO 2 caused alterations in the activities of CAT and GST. -- Abstract: The popularity of TiO 2 nanoparticles (nano-TiO 2 ) lies in their wide range of nanotechnological applications, together with low toxicity. Meanwhile, recent studies have shown that the photocatalytic properties of this material can result in alterations in their behavior in the environment, causing effects that have not yet been fully elucidated. The objective of this study was to evaluate the toxicity of two formulations of nano-TiO 2 under different illumination conditions, using an experimental model coherent with the principle of the three Rs of alternative animal experimentation (reduction, refinement, and replacement). Embryos of the fish Danio rerio were exposed for 96 h to different concentrations of nano-TiO 2 in the form of anatase (TA) or an anatase/rutile mixture (TM), under either visible light or a combination of visible and ultraviolet light (UV). The acute toxicity and sublethal parameters evaluated included survival rates, malformation, hatching, equilibrium, and overall length of the larvae, together with biochemical biomarkers (specific activities of catalase (CAT), glutathione S-transferase (GST), and acid phosphatase (AP)). Both TA and TM caused accelerated hatching of the larvae. Under UV irradiation, there was greater mortality of the larvae of the groups exposed to TM, compared to those exposed to TA. Exposure to TM under UV irradiation altered the equilibrium of the larvae. Alterations in the activities of CAT and GST were indicative of oxidative stress, although no clear dose-response relationship was observed. The effects of nano-TiO 2 appeared to depend on both the type of formulation and the illumination condition. The findings contribute to elucidation of the factors involved in the toxicity

  16. Environmentally toxicant exposures induced intragenerational transmission of liver abnormalities in mice

    Directory of Open Access Journals (Sweden)

    Mohamed A. Al-Griw

    2017-08-01

    Full Text Available Environmental toxicants such as chemicals, heavy metals, and pesticides have been shown to promote transgenerational inheritance of abnormal phenotypes and/or diseases to multiple subsequent generations following parental and/ or ancestral exposures. This study was designed to examine the potential transgenerational action of the environmental toxicant trichloroethane (TCE on transmission of liver abnormality, and to elucidate the molecular etiology of hepatocyte cell damage. A total of thirty two healthy immature female albino mice were randomly divided into three equal groups as follows: a sham group, which did not receive any treatment; a vehicle group, which received corn oil alone, and TCE treated group (3 weeks, 100 μg/kg i.p., every 4th day. The F0 and F1 generation control and TCE populations were sacrificed at the age of four months, and various abnormalities histpathologically investigated. Cell death and oxidative stress indices were also measured. The present study provides experimental evidence for the inheritance of environmentally induced liver abnormalities in mice. The results of this study show that exposure to the TCE promoted adult onset liver abnormalities in F0 female mice as well as unexposed F1 generation offspring. It is the first study to report a transgenerational liver abnormalities in the F1 generation mice through maternal line prior to gestation. This finding was based on careful evaluation of liver histopathological abnormalities, apoptosis of hepatocytes, and measurements of oxidative stress biomarkers (lipid peroxidation, protein carbonylation, and nitric oxide in control and TCE populations. There was an increase in liver histopathological abnormalities, cell death, and oxidative lipid damage in F0 and F1 hepatic tissues of TCE treated group. In conclusion, this study showed that the biological and health impacts of environmental toxicant TCE do not end in maternal adults, but are passed on to offspring

  17. Modeling U-Shaped Exposure-Response Relationships for Agents that Demonstrate Toxicity Due to Both Excess and Deficiency.

    Science.gov (United States)

    Milton, Brittany; Farrell, Patrick J; Birkett, Nicholas; Krewski, Daniel

    2017-02-01

    Essential elements such as copper and manganese may demonstrate U-shaped exposure-response relationships due to toxic responses occurring as a result of both excess and deficiency. Previous work on a copper toxicity database employed CatReg, a software program for categorical regression developed by the U.S. Environmental Protection Agency, to model copper excess and deficiency exposure-response relationships separately. This analysis involved the use of a severity scoring system to place diverse toxic responses on a common severity scale, thereby allowing their inclusion in the same CatReg model. In this article, we present methods for simultaneously fitting excess and deficiency data in the form of a single U-shaped exposure-response curve, the minimum of which occurs at the exposure level that minimizes the probability of an adverse outcome due to either excess or deficiency (or both). We also present a closed-form expression for the point at which the exposure-response curves for excess and deficiency cross, corresponding to the exposure level at which the risk of an adverse outcome due to excess is equal to that for deficiency. The application of these methods is illustrated using the same copper toxicity database noted above. The use of these methods permits the analysis of all available exposure-response data from multiple studies expressing multiple endpoints due to both excess and deficiency. The exposure level corresponding to the minimum of this U-shaped curve, and the confidence limits around this exposure level, may be useful in establishing an acceptable range of exposures that minimize the overall risk associated with the agent of interest. © 2016 Society for Risk Analysis.

  18. Current status of personnel exposure at nuclear power plants and other medical, industrial and educational facilities in JAPAN

    International Nuclear Information System (INIS)

    Sasaki, Fumiaki

    1991-01-01

    The state of radiation exposure of the workers engaging in radiation works in Japanese nuclear power stations, the factors of the radiation exposure of the workers engaging in radiation works, the countermeasures for reducing exposure in nuclear power stations, the state of radiation exposure of doctors, the workers engaging in radiation works, researchers and others in medical, industrial, research and educational and other facilities in Japan, the factors of their radiation exposure and the countermeasures for reducing the exposure, and the comparison of the exposure in nuclear power stations with that in medical, industrial, research and educational facilities are reported. (K.I.)

  19. Monitoring Exposure to Ebola and Health of U.S. Military Personnel Deployed in Support of Ebola Control Efforts - Liberia, October 25, 2014-February 27, 2015.

    Science.gov (United States)

    Cardile, Anthony P; Murray, Clinton K; Littell, Christopher T; Shah, Neel J; Fandre, Matthew N; Drinkwater, Dennis C; Markelz, Brian P; Vento, Todd J

    2015-07-03

    In response to the unprecedented Ebola virus disease (Ebola) outbreak in West Africa, the U.S. government deployed approximately 2,500 military personnel to support the government of Liberia. Their primary missions were to construct Ebola treatment units (ETUs), train health care workers to staff ETUs, and provide laboratory testing capacity for Ebola. Service members were explicitly prohibited from engaging in activities that could result in close contact with an Ebola-infected patient or coming in contact with the remains of persons who had died from unknown causes. Military units performed twice-daily monitoring of temperature and review of exposures and symptoms ("unit monitoring") on all persons throughout deployment, exit screening at the time of departure from Liberia, and post-deployment monitoring for 21 days at segregated, controlled monitoring areas on U.S. military installations. A total of 32 persons developed a fever during deployment from October 25, 2014, through February 27, 2015; none had a known Ebola exposure or developed Ebola infection. Monitoring of all deployed service members revealed no Ebola exposures or infections. Given their activity restrictions and comprehensive monitoring while deployed to Liberia, U.S. military personnel constitute a unique population with a lower risk for Ebola exposure compared with those working in the country without such measures.

  20. Comparative proteomic analysis reveals heart toxicity induced by chronic arsenic exposure in rats

    DEFF Research Database (Denmark)

    Huang, Qingyu; Xi, Guochen; Alamdar, Ambreen

    2017-01-01

    Arsenic is a widespread metalloid in the environment, which poses a broad spectrum of adverse effects on human health. However, a global view of arsenic-induced heart toxicity is still lacking, and the underlying molecular mechanisms remain unclear. By performing a comparative quantitative...... proteomic analysis, the present study aims to investigate the alterations of proteome profile in rat heart after long-term exposure to arsenic. As a result, we found that the abundance of 81 proteins were significantly altered by arsenic treatment (35 up-regulated and 46 down-regulated). Among these, 33...... proteins were specifically associated with cardiovascular system development and function, including heart development, heart morphology, cardiac contraction and dilation, and other cardiovascular functions. It is further proposed that the aberrant regulation of 14 proteins induced by arsenic would disturb...

  1. Problems with regard to occupational exposure of external personnel (section 15 of the German Radiation Protection Ordinance)

    International Nuclear Information System (INIS)

    Roth, W.

    2002-01-01

    The annual radiation dose to the group of external personnel working in nuclear facilities accounts for more than 39% of the total annual collective dose of all occupationally exposed persons in Germany. This is a fact causing problems for plant operators employing external personnel as well as the sending companies, with respect to compliance with the radiation protection regulations. The amended German Radiation Protection Ordinance does not really make things easier in this respect, but in fact is expected to aggravate the situation in the course of increasing globalisation in the industrial sector. (orig./CB) [de

  2. Metabolic responses of Eisenia fetida after sub-lethal exposure to organic contaminants with different toxic modes of action

    International Nuclear Information System (INIS)

    McKelvie, Jennifer R.; Wolfe, David M.; Celejewski, Magda A.; Alaee, Mehran; Simpson, Andre J.; Simpson, Myrna J.

    2011-01-01

    Nuclear magnetic resonance (NMR) - based metabolomics has the potential to identify toxic responses of contaminants within a mixture in contaminated soil. This study evaluated the metabolic response of Eisenia fetida after exposure to an array of organic compounds to determine whether contaminant-specific responses could be identified. The compounds investigated in contact tests included: two pesticides (carbaryl and chlorpyrifos), three pharmaceuticals (carbamazephine, estrone and caffeine), two persistent organohalogens (Aroclor 1254 and PBDE 209) and two industrial compounds (nonylphenol and dimethyl phthalate). Control and contaminant-exposed metabolic profiles were distinguished using principal component analysis and potential contaminant-specific biomarkers of exposure were found for several contaminants. These results suggest that NMR-based metabolomics offers considerable promise for differentiating between the different toxic modes of action (MOA) associated with sub-lethal toxicity to earthworms. - Highlights: → NMR-based earthworm metabolomic analysis of the toxic mode of action of various environmental contaminants. → Organic chemicals with different toxic modes of action resulted in varied metabolomic responses for E. fetida. → NMR-based metabolomics differentiates between the different modes of action associated with sub-lethal toxicity. - 1 H NMR metabolomics was used to identify potential biomarkers of organic contaminant exposure in Eisenia fetida earthworms.

  3. Metabolic responses of Eisenia fetida after sub-lethal exposure to organic contaminants with different toxic modes of action

    Energy Technology Data Exchange (ETDEWEB)

    McKelvie, Jennifer R.; Wolfe, David M.; Celejewski, Magda A. [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada); Alaee, Mehran [Environment Canada, 867 Lakeshore Rd., P.O. Box 5050, Burlington, ON L7R 4A6 (Canada); Simpson, Andre J. [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada); Simpson, Myrna J., E-mail: myrna.simpson@utoronto.ca [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada)

    2011-12-15

    Nuclear magnetic resonance (NMR) - based metabolomics has the potential to identify toxic responses of contaminants within a mixture in contaminated soil. This study evaluated the metabolic response of Eisenia fetida after exposure to an array of organic compounds to determine whether contaminant-specific responses could be identified. The compounds investigated in contact tests included: two pesticides (carbaryl and chlorpyrifos), three pharmaceuticals (carbamazephine, estrone and caffeine), two persistent organohalogens (Aroclor 1254 and PBDE 209) and two industrial compounds (nonylphenol and dimethyl phthalate). Control and contaminant-exposed metabolic profiles were distinguished using principal component analysis and potential contaminant-specific biomarkers of exposure were found for several contaminants. These results suggest that NMR-based metabolomics offers considerable promise for differentiating between the different toxic modes of action (MOA) associated with sub-lethal toxicity to earthworms. - Highlights: > NMR-based earthworm metabolomic analysis of the toxic mode of action of various environmental contaminants. > Organic chemicals with different toxic modes of action resulted in varied metabolomic responses for E. fetida. > NMR-based metabolomics differentiates between the different modes of action associated with sub-lethal toxicity. - {sup 1}H NMR metabolomics was used to identify potential biomarkers of organic contaminant exposure in Eisenia fetida earthworms.

  4. Epigenetics as a mechanism linking developmental exposures to long-term toxicity.

    Science.gov (United States)

    Barouki, R; Melén, E; Herceg, Z; Beckers, J; Chen, J; Karagas, M; Puga, A; Xia, Y; Chadwick, L; Yan, W; Audouze, K; Slama, R; Heindel, J; Grandjean, P; Kawamoto, T; Nohara, K

    2018-05-01

    A variety of experimental and epidemiological studies lend support to the Developmental Origin of Health and Disease (DOHaD) concept. Yet, the actual mechanisms accounting for mid- and long-term effects of early-life exposures remain unclear. Epigenetic alterations such as changes in DNA methylation, histone modifications and the expression of certain RNAs have been suggested as possible mediators of long-term health effects of environmental stressors. This report captures discussions and conclusions debated during the last Prenatal Programming and Toxicity meeting held in Japan. Its first aim is to propose a number of criteria that are critical to support the primary contribution of epigenetics in DOHaD and intergenerational transmission of environmental stressors effects. The main criteria are the full characterization of the stressors, the actual window of exposure, the target tissue and function, the specificity of the epigenetic changes and the biological plausibility of the linkage between those changes and health outcomes. The second aim is to discuss long-term effects of a number of stressors such as smoking, air pollution and endocrine disruptors in order to identify the arguments supporting the involvement of an epigenetic mechanism. Based on the developed criteria, missing evidence and suggestions for future research will be identified. The third aim is to critically analyze the evidence supporting the involvement of epigenetic mechanisms in intergenerational and transgenerational effects of environmental exposure and to particularly discuss the role of placenta and sperm. While the article is not a systematic review and is not meant to be exhaustive, it critically assesses the contribution of epigenetics in the long-term effects of environmental exposures as well as provides insight for future research. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Adolescent Exposure to Toxic Volatile Organic Chemicals From E-Cigarettes.

    Science.gov (United States)

    Rubinstein, Mark L; Delucchi, Kevin; Benowitz, Neal L; Ramo, Danielle E

    2018-04-01

    There is an urgent need to understand the safety of e-cigarettes with adolescents. We sought to identify the presence of chemical toxicants associated with e-cigarette use among adolescents. Adolescent e-cigarette users (≥1 use within the past 30 days, ≥10 lifetime e-cigarette use episodes) were divided into e-cigarette-only users (no cigarettes in the past 30 days, urine 4-[methylnitrosamino]-1-[3-pyridyl]-1-butanol [NNAL] level 30 pg/mL; n = 16), and never-using controls ( N = 20). Saliva was collected within 24 hours of the last e-cigarette use for analysis of cotinine and urine for analysis of NNAL and levels of 8 volatile organic chemical compounds. Bivariate analyses compared e-cigarette-only users with dual users, and regression analyses compared e-cigarette-only users with dual users and controls on levels of toxicants. The participants were 16.4 years old on average. Urine excretion of metabolites of benzene, ethylene oxide, acrylonitrile, acrolein, and acrylamide was significantly higher in dual users versus e-cigarette-only users (all P < .05). Excretion of metabolites of acrylonitrile, acrolein, propylene oxide, acrylamide, and crotonaldehyde were significantly higher in e-cigarette-only users compared with controls (all P < .05). Although e-cigarette vapor may be less hazardous than tobacco smoke, our findings can be used to challenge the idea that e-cigarette vapor is safe, because many of the volatile organic compounds we identified are carcinogenic. Messaging to teenagers should include warnings about the potential risk from toxic exposure to carcinogenic compounds generated by these products. Copyright © 2018 by the American Academy of Pediatrics.

  6. Toxicity and Immunogenicity in Murine Melanoma following Exposure to Physical Plasma-Derived Oxidants

    Directory of Open Access Journals (Sweden)

    Sander Bekeschus

    2017-01-01

    Full Text Available Metastatic melanoma is an aggressive and deadly disease. Therapeutic advance has been achieved by antitumor chemo- and radiotherapy. These modalities involve the generation of reactive oxygen and nitrogen species, affecting cellular viability, migration, and immunogenicity. Such species are also created by cold physical plasma, an ionized gas capable of redox modulating cells and tissues without thermal damage. Cold plasma has been suggested for anticancer therapy. Here, melanoma cell toxicity, motility, and immunogenicity of murine metastatic melanoma cells were investigated following plasma exposure in vitro. Cells were oxidized by plasma, leading to decreased metabolic activity and cell death. Moreover, plasma decelerated melanoma cell growth, viability, and cell cycling. This was accompanied by increased cellular stiffness and upregulation of zonula occludens 1 protein in the cell membrane. Importantly, expression levels of immunogenic cell surface molecules such as major histocompatibility complex I, calreticulin, and melanocortin receptor 1 were significantly increased in response to plasma. Finally, plasma treatment significantly decreased the release of vascular endothelial growth factor, a molecule with importance in angiogenesis. Altogether, these results suggest beneficial toxicity of cold plasma in murine melanomas with a concomitant immunogenicity of potential interest in oncology.

  7. [Evaluation of radiation exposure of personnel in an orthopaedic and trauma operation theatre using the new real-time dosimetry system "dose aware"].

    Science.gov (United States)

    Müller, M C; Strauss, A; Pflugmacher, R; Nähle, C P; Pennekamp, P H; Burger, C; Wirtz, D C

    2014-08-01

    There is a positive correlation between operation time and staff exposure to radiation during intraoperative use of C-arm fluoroscopy. Due to harmful effects of exposure to long-term low-dose radiation for both the patient and the operating team it should be kept to a minimum. AIM of this study was to evaluate a novel dosimeter system called Dose Aware® (DA) enabling radiation exposure feedback of the personal in an orthopaedic and trauma operation theatre in real-time. Within a prospective study over a period of four month, DA was applied by the operation team during 104 orthopaedic and trauma operations in which the C-arm fluoroscope was used in 2D-mode. During ten operation techniques, radiation exposure of the surgeon, the first assistant, the theatre nurse and the anaesthesiologist was evaluated. Seventy-three operations were analysed. The surgeon achieved the highest radiation exposure during dorsolumbar spinal osteosynthesis, kyphoplasty and screw fixation of sacral fractures. The first assistant received a higher radiation exposure compared to the surgeon during plate osteosynthesis of distal radius fractures (157 %), intramedullary nailing of pertrochanteric fractures (143 %) and dorsolumbar spinal osteosynthesis (240 %). During external fixation of ankle fractures (68 %) and screw fixation of sacral fractures (66 %) radiation exposure of the theatre nurse exceeded 50 % of the surgeon's radiation exposure. During plate osteosynthesis of distal radius fractures (157 %) and intramedullary splinting of clavicular fractures (115 %), the anaesthesiologist received a higher radiation exposure than the surgeon. The novel dosimeter system DA provides real-time radiation exposure feedback of the personnel in an orthopaedic and trauma operation theatre for the first time. Data of this study demonstrate that radiation exposure of the personnel depends on the operation type. The first assistant, the theatre nurse and the anaesthesiologist might be

  8. Effect of exposure routes on the relationships of lethal toxicity to rats from oral, intravenous, intraperitoneal and intramuscular routes.

    Science.gov (United States)

    Ning, Zhong H; Long, Shuang; Zhou, Yuan Y; Peng, Zi Y; Sun, Yi N; Chen, Si W; Su, Li M; Zhao, Yuan H

    2015-11-01

    The lethal toxicity values (log 1/LD(50)) of 527 aliphatic and aromatic compounds in oral, intravenous, intramuscular and intraperitoneal routes were used to investigate the relationships of log 1/LD(50) from different exposure routes. Regression analysis shows that the log 1/LD(50) values are well correlated between intravenous and intraperitoneal or intramuscular injections. However, the correlations between oral and intravenous or intraperitoneal routes are relatively poor. Comparison of the average residuals indicates that intravenous injection is the most sensitive exposure route and oral administration is the least sensitive exposure route. This is attributed to the difference in kinetic process of toxicity testing. The toxic effect of a chemical can be similar or significantly different between exposure routes, depending on the absorption rates of chemicals into blood. Inclusion of hydrophobic parameter and fractions of ionic forms can improve the correlations between intravenous and intraperitoneal or oral routes, but not between intraperitoneal and oral routes. This is due to the differences of absorption rate in different exposure environments from different routes. Several factors, such as experimental uncertainty, metabolism and toxic kinetics, can affect the correlations between intravenous and intraperitoneal or oral routes. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Relative toxicity of bifenthrin to Hyalella azteca in 10 day versus 28 day exposures.

    Science.gov (United States)

    Anderson, Brian S; Phillips, Bryn M; Voorhees, Jennifer P; Petersen, Megan A; Jennings, Lydia L; Fojut, Tessa L; Vasquez, Martice E; Siegler, Catherine; Tjeerdema, Ronald S

    2015-04-01

    Many watersheds in the Central Valley region of California are listed as impaired due to pyrethroid-associated sediment toxicity. The Central Valley Regional Water Quality Control Board is developing numeric sediment quality criteria for pyrethroids, beginning with bifenthrin. Criteria are being developed using existing data, along with data from 10 d and 28 d toxicity tests with Hyalella azteca conducted as part of the current study. A single range-finder and 2 definitive tests were conducted for each test duration. Median lethal concentrations (LC50s), as well as LC20s and inhibition concentrations (IC20s) were calculated based on measured whole sediment bifenthrin concentrations and interstitial water concentrations. Sediment LC50s were also corrected for organic C content. Average LC50s were not significantly different in 10 d versus 28 d tests with H. azteca: 9.1 and 9.6 ng/g bifenthrin for 10 d and 28 d tests, respectively. Average LC20 values were also similar with concentrations at 7.1 and 7.0 for 10 d and 28 d tests, respectively. Bifenthrin inhibition concentrations (IC20s) based on amphipod growth were variable, particularly in the 28 d tests, where a clear dose-response relationship was observed in only 1 of the definitive experiments. Average amphipod growth IC20s were 3.9 and 9.0 ng/g for 10 d and 28 d tests, respectively. Amphipod growth calculated as biomass resulted in IC20s of 4.1 and 6.3 ng/g for the 10 d and 28 d tests, respectively. Lack of a clear growth effect in the longer term test may be related to the lack of food adjustment to account for amphipod mortality in whole sediment exposures. The average C-corrected LC50s were 1.03 and 1.09 μg/g OC for the 10 d and 28 d tests, respectively. Interstitial water LC50s were determined as the measured dissolved concentration of bifenthrin relative to interstitial water dissolved organic carbon. The average LC50s for dissolved interstitial water bifenthrin were

  10. [Behavioral-cognitive disorders due to chronic exposure to industrial and environmental toxic substances].

    Science.gov (United States)

    Mangone, Carlos A; Genovese, Osvaldo; Abel, Carlos

    2006-01-01

    A review of neurotoxics is made, given the low tendency to investigate for chronic exposure to environmental and industrial potential central nervous system toxic substances (heavy metals, insecticides, organic solvents and carbon monoxide) in the history of a patient consulting for behavioral - cognitive complains, and considering the potential overturn of the disease if a correct diagnosis and early treatment is made. to determine the onset of the cognitive - behavioral features, presentation pattern, diagnosis and treatment of such neurotoxics (NT). systematized search in Cochrane and Medline reviews, Embase and Lilacs. chronic exposure to neurotoxics can produce personality changes (sleeping problems, excitation, depression, delusions and hallucinations) as well as cognitive problems (memory, learning, language and cognitive reaction problems). NT may cause changes in the neuron morphology and its sub cellular structures, affecting its normal biochemistry and physiology (proteins and neurotransmitters synthesis). The clinical history, diagnosis and treatment of each neurotoxic are discussed. The NT must be taken in consideration among the possible different etiologies when a patient with a bizarre behavioral cognitive syndrome is examined.

  11. The absorption, distribution, excretion and toxicity of mesoporous silica nanoparticles in mice following different exposure routes.

    Science.gov (United States)

    Fu, Changhui; Liu, Tianlong; Li, Linlin; Liu, Huiyu; Chen, Dong; Tang, Fangqiong

    2013-03-01

    Mesoporous silica nanoparticles (MSNs) are emerging as one of the promising nanomaterials for biomedical applications, but the nanomaterials-body interaction exposed by different administration routes remained poorly understood. In the present study, a systematic investigation of the absorption, distribution, excretion and toxicity of silica nanoparticles (SNs) with the average size of 110 nm after four different exposure routes including intravenous, hypodermic, intramuscular injection and oral administration to mice were achieved. The results showed that a fraction of the SNs administrated by the intramuscular and hypodermic injection could cross different biological barriers into the liver but with a low absorption rate. Exposing by oral administration, SNs were absorbed into the intestinal tract and persisted in the liver. And SNs administrated by intravenous injection were mainly present in the liver and spleen. In addition, SNs could cause inflammatory response around the injection sites after intramuscular and hypodermic injection. It was also found that SNs were mainly excreted through urine and feces after different exposure routes. This study will be helpful for selecting the appropriate exposed routes for the development of nanomaterials-based drug delivery system for biomedical applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Oocyte toxicity: female germ-cell loss from radiation and chemical exposures

    International Nuclear Information System (INIS)

    Dobson, R.L.

    1984-01-01

    In some mammals, female germ cells are extraordinarily sensitive to killing by exposure to ionizing radiation, especially during development. Immature oocytes, which constitute the lifetime germ-cell pool of the female, have an LD 50 in juvenile mice of only 6 rad (compared with typical LD 50 s of 100-300 rad for most other cell types studied). Essentially, the entire germ-cell supply in female squirrel monkeys is destroyed prenatally by exposure of only 0.7 rad/day. Severe but lesser destruction has been found in other species. However, evidence suggests (though not ruled out for all developmental stages) that unusually high sensitivity probably does not occur in the human female. Germ cells can also be killed by certain chemicals, and similarities exist between chemical and radiation effects. More than 75 compounds have been quantitatively studied in mice, with determination of OTI values (OTI = oocyte toxicity index = mouse LD 50 /oocyte LD 50 ) to measure the degree of preferential oocyte killing. High sensitivity in mice does not mean necessarily high sensitivity in women. Of special interest is the recent discovery that the lethal target in the extremely sensitive mouse immature oocyte is probably the plasma membrane, not DNA. Since mouse data form the main basis from which human genetic hazard (for both radiation and chemicals) is estimated, this has important implications for the determination of genetic risk in women

  13. Comparative proteomic analysis reveals heart toxicity induced by chronic arsenic exposure in rats.

    Science.gov (United States)

    Huang, Qingyu; Xi, Guochen; Alamdar, Ambreen; Zhang, Jie; Shen, Heqing

    2017-10-01

    Arsenic is a widespread metalloid in the environment, which poses a broad spectrum of adverse effects on human health. However, a global view of arsenic-induced heart toxicity is still lacking, and the underlying molecular mechanisms remain unclear. By performing a comparative quantitative proteomic analysis, the present study aims to investigate the alterations of proteome profile in rat heart after long-term exposure to arsenic. As a result, we found that the abundance of 81 proteins were significantly altered by arsenic treatment (35 up-regulated and 46 down-regulated). Among these, 33 proteins were specifically associated with cardiovascular system development and function, including heart development, heart morphology, cardiac contraction and dilation, and other cardiovascular functions. It is further proposed that the aberrant regulation of 14 proteins induced by arsenic would disturb cardiac contraction and relaxation, impair heart morphogenesis and development, and induce thrombosis in rats, which is mediated by the Akt/p38 MAPK signaling pathway. Overall, these findings will augment our knowledge of the involved mechanisms and develop useful biomarkers for cardiotoxicity induced by environmental arsenic exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. [Occupational toxic exposure in the pregnant woman. 1: principles fo individual risk assessment ].

    Science.gov (United States)

    Testud, F; Lambert-Chhum, R; Bellemin, B; Descotes, J

    2001-12-01

    Many women of childbearing age are occupationally exposed to chemicals and concerned with the ensuing risk when pregnant. To describe the principles of individual risk assessment to be applied in pregnant women or women wishing to become pregnant that are exposed to chemicals at the workplace. Each request for risk assessment is based on a comprehensive review of the hazards of the handled products together with a thorough evaluation of the actual exposure at the workplace. A toxicological advice is then written to the gynecologist or the general practitioner in charge of the patient. When the exposure is estimated to be hazardous for the pregnancy, either total withdrawal, avoidance of certain activities or improvements of individual protective devices are recommended. The outcome of the pregnancy is systematically followed-up. An objective assessment of toxic risks in pregnant women exposed to chemicals at the workplace can be done. Thus, patients who must be withdrawn or benefit from improvements of their workstation can be selected.

  15. Evaluation of the toxicity data for peracetic acid in deriving occupational exposure limits: a minireview.

    Science.gov (United States)

    Pechacek, Nathan; Osorio, Magdalena; Caudill, Jeff; Peterson, Bridget

    2015-02-17

    Peracetic acid (PAA) is a peroxide-based chemistry that is highly reactive and can produce strong local effects upon direct contact with the eyes, skin and respiratory tract. Given its increasing prominence in industry, attention has focused on health hazards and associated risks for PAA in the workplace. Occupational exposure limits (OEL) are one means to mitigate risks associated with chemical hazards in the workplace. A mini-review of the toxicity data for PAA was conducted in order to determine if the data were sufficient to derive health-based OELs. The available data for PAA frequently come from unpublished studies that lack sufficient study details, suffer from gaps in available information and often follow unconventional testing methodology. Despite these limitations, animal and human data suggest sensory irritation as the most sensitive endpoint associated with inhalation of PAA. Rodent RD50 data (the concentration estimated to cause a 50% depression in respiratory rate) were selected as the critical studies in deriving OELs. Based on these data, a range of 0.36-0.51mg/m(3) (0.1-0.2ppm) was calculated for a time-weighted average (TWA), and 1.2-1.7mg/m(3) (0.4-0.5ppm) as a range for a short-term exposure limit (STEL). These ranges compare favorably to other published OELs for PAA. Considering the applicable health hazards for this chemistry, a joint TWA/STEL OEL approach for PAA is deemed the most appropriate in assessing workplace exposures to PAA, and the selection of specific values within these proposed ranges represents a risk management decision. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. Uncovering the exposure mechanisms of sunken heavy oil that makes it chronically toxic to early life stages of fish

    International Nuclear Information System (INIS)

    Martin, J.; Young, G.; Lemire, B.; Hodson, P.

    2010-01-01

    A train derailment in 2005 caused the release of 150,000 litres of No. 6 heavy fuel oil into a lake in Alberta. The oil is a residue of the crude oil refinement process and contains 3-4 ringed alkylated forms of polycyclic aromatic hydrocarbons (PAH) that are known to cause sub-lethal toxic responses during the early life stages of rainbow trout. Because the oil does not disperse well, oil patches still persist in near-shore sediments of the lake where fish spawn. This study assessed how the behaviour of heavy oil in water interacts with exposure and toxicity to the early life stages of fish. Daily renewal tests with heavy fuel oil coated on glass plate demonstrated higher levels of toxicity to trout embryos than oil that was mechanically or chemically dispersed. A flow-through oil gravel column was used to assess whether the toxic constituents of the heavy oil are transferred quickly enough to cause toxicity. The aim of the study was to develop exposure and toxicity test methods that accurately reflect the behaviour of heavy oil after a spill.

  17. Malingering in Toxic Exposure. Classification Accuracy of Reliable Digit Span and WAIS-III Digit Span Scaled Scores

    Science.gov (United States)

    Greve, Kevin W.; Springer, Steven; Bianchini, Kevin J.; Black, F. William; Heinly, Matthew T.; Love, Jeffrey M.; Swift, Douglas A.; Ciota, Megan A.

    2007-01-01

    This study examined the sensitivity and false-positive error rate of reliable digit span (RDS) and the WAIS-III Digit Span (DS) scaled score in persons alleging toxic exposure and determined whether error rates differed from published rates in traumatic brain injury (TBI) and chronic pain (CP). Data were obtained from the files of 123 persons…

  18. Extracorporeal Membrane Oxygenation (ECMO) for Severe Toxicological Exposures: Review of the Toxicology Investigators Consortium (ToxIC).

    Science.gov (United States)

    Wang, G S; Levitan, R; Wiegand, T J; Lowry, J; Schult, R F; Yin, S

    2016-03-01

    Although there have been many developments related to specific strategies for treating patients after poisoning exposures, the mainstay of therapy remains symptomatic and supportive care. One of the most aggressive supportive modalities is extracorporeal membrane oxygenation (ECMO). Our goal was to describe the use of ECMO for toxicological exposures reported to the American College of Medical Toxicology (ACMT) Toxicology Investigators Consortium (ToxIC). We performed a retrospective review of the ACMT ToxIC Registry from January 1, 2010 to December 31, 2013. Inclusion criteria included patients aged 0 to 89 years, evaluated between January 2010 through December 2013, and received ECMO for toxicological exposure. There were 26,271 exposures (60 % female) reported to the ToxIC Registry, 10 (0.0004 %) received ECMO: 4 pediatric (18 years). Time of initiation of ECMO ranged from 4 h to 4 days, with duration from 15 h to 12 days. Exposures included carbon monoxide/smoke inhalation (2), bitter almonds, methanol, and several medications including antihistamines (2), antipsychotic/antidepressant (2), cardiovascular drugs (2), analgesics (2), sedative/hypnotics (2), and antidiabetics (2). Four ECMO patients received cardiopulmonary resuscitation (CPR) during their hospital course, and the overall survival rate was 80 %. ECMO was rarely used for poisoning exposures in the ACMT ToxIC Registry. ECMO was utilized for a variety of ages and for pharmaceutical and non-pharmaceutical exposures. In most cases, ECMO was administered prior to cardiovascular failure, and survival rate was high. If available, ECMO may be a valid treatment modality.

  19. Reduction of systemic exposure and toxicity of cisplatin by encapsulation in poly-lactide-co-glycolide.

    Science.gov (United States)

    Verrijk, R; Smolders, I J; Bosnie, N; Begg, A C

    1992-12-01

    The tissue distribution and normal tissue toxicity of cisplatin (cDDP) administered as poly-lactide-co-glycolide (PLAGA) microspheres, developed for loco-regional administration of cDDP to the liver, were studied in Wag/Rij rats. Venoportal administration of this formulation resulted in a reduction in total systemic and renal toxicity, which correlated with a decrease in normal tissue exposure to cDDP while maintaining high liver platinum levels. Liver-to-kidney platinum level ratios were 28 times higher after 4 h and 19 times higher after 24 h with PLAGA-cDDP microspheres than with free cDDP. Liver-to-blood platinum ratios at these times were 38 times and 36 times higher using PLAGA-cDDP. In a CC531 colon carcinoma liver micrometastases model, cytotoxicity of microsphere-released cDDP was confirmed in vivo by equal inhibition of tumor growth by PLAGA-cDDP and free cDDP over a period of 26 days. Free cDDP, however, caused significantly more histological renal damage and total body weight loss. The results were supported by the finding of higher plasma creatinine and urea concentrations 26 days after administration of free cDDP. Kidney platinum levels were 7 times lower when PLAGA-cDDP was used. These findings indicate a sparing effect on normal tissues when cDDP is targeted to the liver by formulation in PLAGA. PLAGA-cDDP microspheres may, therefore, be a useful and effective addition to current techniques of loco-regional chemotherapy for disseminated hepatic tumors.

  20. Copper pellets simulating oral exposure to copper ammunition: Absence of toxicity in American kestrels (Falco sparverius)

    Science.gov (United States)

    Franson, J. Christian; Lahner, Lesanna L.; Meteyer, Carol U.; Rattner, Barnett A.

    2012-01-01

    To evaluate the potential toxicity of copper (Cu) in raptors that may consume Cu bullets, shotgun pellets containing Cu, or Cu fragments as they feed on wildlife carcasses, we studied the effects of metallic Cu exposure in a surrogate, the American kestrel (Falco sparverius). Sixteen kestrels were orally administered 5 mg Cu/g body mass in the form of Cu pellets (1.18–2.00 mm in diameter) nine times during 38 days and 10 controls were sham gavaged on the same schedule. With one exception, all birds retained the pellets for at least 1 h, but most (69%) regurgitated pellets during a 12-h monitoring period. Hepatic Cu concentrations were greater in kestrels administered Cu than in controls, but there was no difference in Cu concentrations in the blood between treated and control birds. Concentration of the metal-binding protein metallothionein was greater in male birds that received Cu than in controls, whereas concentrations in female birds that received Cu were similar to control female birds. Hepatic Cu and metallothionein concentrations in kestrels were significantly correlated. Histopathologic alterations were noted in the pancreas of four treated kestrels and two controls, but these changes were not associated with hepatic or renal Cu concentrations, and no lesions were seen in other tissues. No clinical signs were observed, and there was no treatment effect on body mass; concentrations of Cu, hemoglobin, or methemoglobin in the blood; or Cu concentrations in kidney, plasma biochemistries, or hematocrit. Based on the parameters we measured, ingested Cu pellets pose little threat to American kestrels (and presumably phylogenetically related species), although the retention time of pellets in the stomach was of relatively short duration. Birds expected to regurgitate Cu fragments with a frequency similar to kestrels are not likely to be adversely affected by Cu ingestion, but the results of our study do not completely rule out the potential for toxicity in

  1. Reproductive toxicity in rats after chronic oral exposure to low dose of depleted uranium

    International Nuclear Information System (INIS)

    Li Rong; Ai Guoping; Xu Hui; Su Yongping; Cheng Tianmin; Leng Yanbing

    2007-01-01

    Objective: To study the reproductive toxicity in rats induced by low dose of depleted uranium (DU). Methods: Male and female rats(F 0 generation) were exposed to DU in food at doses of 0, 0.4, 4 and 40 mg·kg -1 ·d -1 for 160 days, respectively. Then the activities of enzymes in testis and sexual hormone contents in serum were detected. Mature male rats were mated with female rats exposed to the same doses for 14 days. Pregnant rate and normal labor rate in F 0 rats were detected, as well as the survival rate and weight of F 1 rats within 21 d after birth. Results: No adverse effects of DU on fertility were evident at any dose in F 0 rats. Compared with control group, the rate of pregnancy, normal labor, survival of offspring birth and offspring nurture in F 1 generation of high-dose group reduced to 40.0%, 33.3%, 33.3%, and 33.3%, respectively. The sexual hormone contents in F 0 generation exposed increased, but those in Fl rats decreased significantly. The activities of lactate dehydrogenase-X (LDH-X) decreased in F 1 rats exposed to high-dose of DU, and those of sorbitol dehydrogenase (SDH), LDH and Na + -K + -ATPase decreased in F 1 rats exposed to DU. Conclusions: Reproduction function, growth and development of F 0 rats are not obviously affected after chronic oral exposure to DU, while the toxicity effects in F 1 generation was observed at any dose. (authors)

  2. [Exposure to toxic dose of adrenaline on the functional state of the liver].

    Science.gov (United States)

    Kopylova, S V; Vlasova, K M; Anashkina, A A

    2017-01-01

    The blood biochemical parameters characterizing the functional state of the liver, and the morphological profile of the body after a single exposure to a toxic dose of adrenaline were studied. Studies were conducted on 60 adult rats (female) weighing 0.15-0.2 kg, were divided into groups: intact animals; experience - animals, injected with epinephrine hydrochloride intraperitoneally in a dose of 0.5 mg/kg. All kinds of Biological material (blood, liver) were collected out through one and ten days after the start of the experiment. The degree of influence of high doses of epinephrine were evaluated in terms of lipid peroxidation (LPO) and protein (PSP) in liver homogenates, the concentration of average weight molecules (MSM), the activity of ALT, AST, alkaline phosphatase, LDH, total protein concentration, glucose and lactate in the blood plasma, as well as the determination of the prothrombin time (PTT) with the counting on the basis thereof of international normalized ration (INR). Histology of the liver was studied by light microscopy. It was found that throughout the experiment, there was an increased in the concentration of lipid peroxidation products and protein in liver homogenates, there was an increase in the concentration of MSM 1.7. Twenty-four hours after the administration of a toxic dose of adrenaline observed hyperenzymemia that manifested an increase in the activity of ALT and AST, was an increase in LDH. After 10-day five after the start of the experiment established the presence hyperenzymemia activity decreased ALT and AST, LDH activity remained elevated, total protein level was higher than in the group of animal in which investigations were conducted one day after the start of the experiment, PTV also continued to decline. In histological sections of the development of a pathological condition characterized by circulatory disturbance - plasmatization, both in central and in small vessels. From the hepatocytes both in the center and the periphery

  3. Exposure to toxicants in soil and bottom ash deposits in Agbogbloshie, Ghana: human health risk assessment.

    Science.gov (United States)

    Obiri, S; Ansa-Asare, O D; Mohammed, S; Darko, H F; Dartey, A G

    2016-10-01

    Recycling of e-waste using informal or crude techniques poses serious health risk not only to the workers but also to the environment as whole. It is against this background that this paper sought to measure health risk faced by informal e-waste workers from exposure to toxicants such as lead, cadmium, chromium, copper, arsenic, tin, zinc and cobalt via oral and dermal contact with bottom ash and soil. Using random sampling techniques, 3 separate sites each (where burning and manual dismantling of e-wastes are usually carried) were identified, and a total of 402 samples were collected. The samples were analysed using standard methods for chemical analysis prescribed by the American Water Works Association (AWWA). Concentrations of Pb, Cd, Cr, Cu, As, Sn, Zn and Co in bottom ash samples from location ASH1 are 5388 ± 0.02 mg/kg (Pb), 2.39 ± 0.01 mg/kg (Cd), 42 ± 0.05 mg/kg (Cr), 7940 ± 0.01 mg/kg (Cu), 20 ± 0.07 mg/kg (As), 225 ± 0.04 mg/kg (Sn), 276 ± 0.04 mg/kg (Zn) and 123 ± 0.04 mg/kg (Co), while concentrations of the aforementioned toxicants in soil samples at location ASG1 are as follows: 1685 ± 0.14 mg/kg (Pb), 26.89 ± 0.30 mg/kg (Cd), 36.86 ± 0.02 mg/kg (Cr), 1427 ± 0.08 mg/kg (Cu), 1622 ± 0.12 mg/kg (As), 234 ± 0.25 mg/kg (Sn), 783 ± 0.31 mg/kg (Zn) and 135 ± 0.01 mg/kg (Co); used as input parameters in assessing health risk faced by workers. The results of cancer health risk faced by e-waste workers due to accidental ingestion of As in bottom ash at ASH1 is 4.3 × 10 -3 (CTE) and 6.5 × 10 -2 (RME), i.e. approximately 4 out of 1000 e-waste workers are likely to suffer from cancer-related diseases via central tendency exposure (CTE parameters), and 7 out of every 100 e-waste worker is also likely to suffer from cancer cases by reasonable maximum exposure (RME) parameters, respectively. The cancer health risk results for the other sampling sites were found to have exceeded the acceptable

  4. The moderating impact of interacting with distressed families of decedents on trauma exposure in medical examiner personnel.

    Science.gov (United States)

    Coleman, Jennifer A; Delahanty, Douglas L; Schwartz, Joseph; Murani, Kristina; Brondolo, Elizabeth

    2016-11-01

    Prior research has examined the incidence of posttraumatic stress stemming from either direct or indirect trauma exposure in employees of high-risk occupations. However, few studies have examined the contribution of both direct and indirect trauma exposure in high-risk groups. One particularly salient indirect trauma often endorsed as the most stressful by many occupational groups is interacting with distressed family members of victims of crime, illness, or accidents. The present study examined the extent to which interacting with distressed families moderated the impact of cumulative potentially traumatic event (PTE) exposure on depression and posttraumatic stress disorder (PTSD) symptoms in 245 employees of medical examiner (ME) offices. Employees from 9 ME office sites in the United States participated in an online survey investigating the frequency of work place PTE exposures (direct and indirect) and mental health outcomes. Results revealed that cumulative PTE exposure was associated with higher PTSD symptoms (PTSS) for employees who had higher frequency of exposure to distressed family members. After controlling for cumulative and direct PTE exposure, gender, and office site, exposure to distressed families was significantly associated with depressive symptoms, but not PTSS. Findings of our research underscore the need for training employees in high-risk occupations to manage their reactions to exposure to distraught family members. Employee training may buffer risk for developing PTSD and depression. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  5. Impacts of triclosan exposure on zebrafish early-life stage: Toxicity and acclimation mechanisms.

    Science.gov (United States)

    Falisse, Elodie; Voisin, Anne-Sophie; Silvestre, Frédéric

    2017-08-01

    the acclimation process of larvae exposed to 100μg/L of TCS. Our integrative analysis revealed complex non-monotonic concentration-related effects on zebrafish early-life stages with increased resistance between 50 and 100μg/L exposures. This research highlighted oxidative stress and neurotoxicity as major toxicity mechanisms of TCS during development. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Toxic metals in cigarettes and human health risk assessment associated with inhalation exposure.

    Science.gov (United States)

    Benson, Nsikak U; Anake, Winifred U; Adedapo, Adebusayo E; Fred-Ahmadu, Omowunmi H; Ayejuyo, Olusegun O

    2017-11-08

    This study evaluated the concentrations of cadmium (Cd), copper (Cu), iron (Fe), manganese (Mn), lead (Pb), and zinc (Zn) in 10 branded cigarettes commonly consumed in Nigeria. Chemical sequential extraction method and pseudo-total metal digestion procedure were used for extraction of metals from filler tobacco and filter samples. Samples were analyzed using flame atomic absorption spectrometry (FAAS). The filler tobacco of cigarettes had Cd, Cu, Fe, Mn, Pb, and Zn concentrations in the ranges of 5.90-7.94, 18.26-34.94, 192.61-3494.05, 44.67-297.69, 17.21-74.78, and 47.02-167.31 μg/cigarette, respectively. The minimum and maximum concentrations in the filter samples were 8.67-12.34 μg/g of Cd, 1.77-36.48 μg/g of Cu, 1.83-15.27 μg/g of Fe, 3.82-7.44 μg/g of Mn, 4.09-13.78 μg/g of Pb, and 30.07-46.70 μg/g of Zn. The results of this study showed that the concentrations of heavy metals in the filler tobacco samples were consistently higher than those obtained for the cigarette filters except for Cd. Toxic metals were largely found in the most labile chemical fractions. Moderate to very high risks are found associated with potential exposure to Cd and Pb. The carcinogenic risks posed by Cd and Pb ranged between 1.87E-02 and 2.52E-02, 1.05E-03 and 4.76E-03, respectively, while the non-carcinogenic risk estimates for Cd and Pb were greater than 1.0 (HI > 1). Toxic metals in cigarette may have significant carcinogenic and non-carcinogenic health effects associated with inhalation exposure. Continuous monitoring and regulations of the ingredients of imported and locally produced tobacco products are advocated.

  7. Inhalation toxicity of methanol/gasoline in rats: effects of 13-week exposure.

    Science.gov (United States)

    Poon, R; Park, G; Viau, C; Chu, I; Potvin, M; Vincent, R; Valli, V

    1998-01-01

    The subchronic inhalation toxicity of a methanol/gasoline blend (85% methanol, 15% gasoline, v/v) was studied in rats. Sprague Dawley rats (10 animals per group) of both sexes were exposed to vapours of methanol/gasoline at 50/3, 500/30 and 5000/300ppm for 6 hours per day, 5 days per week, for 13 weeks. Control animals inhaled filtered room air only. Control recovery and high dose recovery groups were also included which inhaled room air for an extra 4 weeks following the treatment period. No clinical signs of toxicity were observed in the treatment group and their growth curves were not significantly different from the control. Except for decreased forelimb grip strength in high dose females, no treatment-related neurobehavioural effects (4-6 hours post inhalation) were observed using screening tests which included cage-side observations, righting reflex, open field activities, and forelimb and hindlimb grip strength. At necropsy, the organ to body weight ratios for the liver, spleen, testes, thymus and lungs were not significantly different from the control group. There were no treatment-related effects in the hematological endpoints and no elevation in serum formate levels. Minimal serum biochemical changes were observed with the only treatment-related change being the decreased creatinine in the females. A dose-related increase in urinary ascorbic acid was detected in males after 2, 4 and 8 weeks of exposure, but not after the 12th week, and in females only at week-2. Increased urinary albumin was observed in treated males starting at the lowest dose and at all exposure periods, but not in females. A treatment-related increase in urinary beta 2-microglobulin was detected in males at week-2 only. Except for mild to moderate mucous cell metaplasia in nasal septum B, which occurred more often and with a slightly higher degree of severity in the low dose groups of both sexes, and presence of a minimal degree of interstitial lymphocyte infiltration in the prostate

  8. Bioaccumulation and toxicity of CuO nanoparticles by a freshwater invertebrate after waterborne and dietborne exposures

    Science.gov (United States)

    Croteau, Marie-Noele; Misra, Superb K.; Luoma, Samuel N.; Valsami-Jones, Eugenia

    2014-01-01

    The incidental ingestion of engineered nanoparticles (NPs) can be an important route of uptake for aquatic organisms. Yet, knowledge of dietary bioavailability and toxicity of NPs is scarce. Here we used isotopically modified copper oxide (65CuO) NPs to characterize the processes governing their bioaccumulation in a freshwater snail after waterborne and dietborne exposures. Lymnaea stagnalis efficiently accumulated 65Cu after aqueous and dietary exposures to 65CuO NPs. Cu assimilation efficiency and feeding rates averaged 83% and 0.61 g g–1 d–1 at low exposure concentrations (–1), and declined by nearly 50% above this concentration. We estimated that 80–90% of the bioaccumulated 65Cu concentration in L. stagnalis originated from the 65CuO NPs, suggesting that dissolution had a negligible influence on Cu uptake from the NPs under our experimental conditions. The physiological loss of 65Cu incorporated into tissues after exposures to 65CuO NPs was rapid over the first days of depuration and not detectable thereafter. As a result, large Cu body concentrations are expected in L. stagnalis after exposure to CuO NPs. To the degree that there is a link between bioaccumulation and toxicity, dietborne exposures to CuO NPs are likely to elicit adverse effects more readily than waterborne exposures.

  9. A two-generation inhalation reproductive toxicity study upon the exposure to manganese chloride.

    Science.gov (United States)

    McGough, Doreen; Jardine, Lynne

    2017-01-01

    A number of published studies have suggested that high levels of exposure to manganese, especially those found in occupational settings, can adversely affect the reproductive system. The objective of this study was therefore to investigate if these findings can be replicated using the Sprague Dawley rat and, if so, to identify those parts of the reproductive system are more susceptible. Male and female rats were exposed to manganese dichloride (MnCl 2 ) via inhalation at concentrations of 0 (air-control); 5, 10 and 20μg/L air over 10 weeks (F0) and over 11 weeks (F1) prior to mating, and then throughout mating, gestation and lactation until termination after the F1 and F2 generation had reached Day 21 of lactation respectively. Animals were monitored for clinical signs of toxicity and for effects on body weight, food consumption, effects on the entire reproductive system including maternal care. The offspring were monitored for survival and growth up to weaning. Blood samples were taken from all adult animals for bioanalytical of manganese analysis prior to dosing, prior to mating and prior to weaning/necropsy. There were no deaths related to treatment, though respiratory tract effects were observed in F0 animals in the mid and high dose animals. Body weight and food consumption were affected at high dose in both generation. There were no treatment-related effects on the oestrous cycles, mating performance, sexual maturity, fertility or duration of gestation or litter size, the sperm motility, count of morphology (sperm) or the ovary follicle scoring in either generation. The No Observed Effect Level (NOEL) for reproductive performance was considered to be the target dose level of 20μg/L. Based on these findings, manganese chloride could not be considered a reprotoxicant under these conditions of exposure. Therefore, soluble and insoluble forms of inorganic manganese compounds by extrapolation cannot be considered as reprotoxicants. Copyright © 2016 Elsevier B

  10. Medical countermeasure against respiratory toxicity and acute lung injury following inhalation exposure to chemical warfare nerve agent VX

    International Nuclear Information System (INIS)

    Nambiar, Madhusoodana P.; Gordon, Richard K.; Rezk, Peter E.; Katos, Alexander M.; Wajda, Nikolai A.; Moran, Theodore S.; Steele, Keith E.; Doctor, Bhupendra P.; Sciuto, Alfred M.

    2007-01-01

    To develop therapeutics against lung injury and respiratory toxicity following nerve agent VX exposure, we evaluated the protective efficacy of a number of potential pulmonary therapeutics. Guinea pigs were exposed to 27.03 mg/m 3 of VX or saline using a microinstillation inhalation exposure technique for 4 min and then the toxicity was assessed. Exposure to this dose of VX resulted in a 24-h survival rate of 52%. There was a significant increase in bronchoalveolar lavage (BAL) protein, total cell number, and cell death. Surprisingly, direct pulmonary treatment with surfactant, liquivent, N-acetylcysteine, dexamethasone, or anti-sense syk oligonucleotides 2 min post-exposure did not significantly increase the survival rate of VX-exposed guinea pigs. Further blocking the nostrils, airway, and bronchioles, VX-induced viscous mucous secretions were exacerbated by these aerosolized treatments. To overcome these events, we developed a strategy to protect the animals by treatment with atropine. Atropine inhibits muscarinic stimulation and markedly reduces the copious airway secretion following nerve agent exposure. Indeed, post-exposure treatment with atropine methyl bromide, which does not cross the blood-brain barrier, resulted in 100% survival of VX-exposed animals. Bronchoalveolar lavage from VX-exposed and atropine-treated animals exhibited lower protein levels, cell number, and cell death compared to VX-exposed controls, indicating less lung injury. When pulmonary therapeutics were combined with atropine, significant protection to VX-exposure was observed. These results indicate that combinations of pulmonary therapeutics with atropine or drugs that inhibit mucous secretion are important for the treatment of respiratory toxicity and lung injury following VX exposure

  11. Human health effects associated with exposure to toxic Cyanobacteria – what is the evidence?

    Science.gov (United States)

    Reports of toxic cyanobacteria blooms are increasing worldwide, as warming water and eutrophic surface water systems support the development of blooms. As awareness of toxic cyanobacteria blooms increases, reports of associated human and animal illnesses have also increased, but ...

  12. Photo-induced toxicity in early life stage fiddler crab (Uca longisignalis) following exposure to Deepwater Horizon oil.

    Science.gov (United States)

    Damare, Leigh M; Bridges, Kristin N; Alloy, Matthew M; Curran, Thomas E; Soulen, Brianne K; Forth, Heather P; Lay, Claire R; Morris, Jeffrey M; Stoeckel, James A; Roberts, Aaron P

    2018-05-01

    The 2010 explosion of the Deepwater Horizon (DWH) oil rig led to the release of millions of barrels of oil in the Gulf of Mexico. Oil in aquatic ecosystems exerts toxicity through multiple mechanisms, including photo-induced toxicity following co-exposure with UV radiation. The timing and location of the spill coincided with both fiddler crab reproduction and peak yearly UV intensities, putting early life stage fiddler crabs at risk of injury due to photo-induced toxicity. The present study assessed sensitivity of fiddler crab larvae to photo-induced toxicity during co-exposure to a range of environmentally relevant dilutions of high-energy water accommodated fractions of DWH oil, and either dark recovery period (duration: 17-h) in between. Survival was significantly decreased in treatments the presence of >10% UV and relatively low concentrations of oil. Results of the present study indicate fiddler crab larvae are sensitive to photo-induced toxicity in the presence of DWH oil. These results are of concern, as fiddler crabs play an important role as ecosystem engineers, modulating sediment biogeochemical processes via burrowing action. Furthermore, they occupy an important place in the food web in the Gulf of Mexico.

  13. Molecular toxicity of cerium oxide nanoparticles to the freshwater alga Chlamydomonas reinhardtii is associated with supra-environmental exposure concentrations

    Science.gov (United States)

    Taylor, Nadine S.; Merrifield, Ruth; Williams, Tim D.; Chipman, J. Kevin; Lead, Jamie R.; Viant, Mark R.

    2016-01-01

    Abstract Ceria nanoparticles (NPs) are widely used as fuel catalysts and consequently are likely to enter the environment. Their potential impacts on. biota at environmentally relevant concentrations, including uptake and toxicity, remain to be elucidated and quantitative data on which to assess risk are sparse. Therefore, a definitive assessment of the molecular and phenotypic effects of ceria NPs was undertaken, using well-characterised mono-dispersed NPs as their toxicity is likely to be higher, enabling a conservative hazard assessment. Unbiased transcriptomics and metabolomics approaches were used to investigate the potential toxicity of tightly constrained 4–5 nm ceria NPs to the unicellular green alga, Chlamydomonas reinhardtii, a sentinel freshwater species. A wide range of exposure concentrations were investigated from predicted environmental levels, to support hazard assessment, to supra-environmental levels to provide insight into molecular toxicity pathways. Ceria NPs were internalised into intracellular vesicles within C. reinhardtii, yet caused no significant effect on algal growth at any exposure concentration. Molecular perturbations were only detected at supra-environmental ceria NP-concentrations, primarily down-regulation of photosynthesis and carbon fixation with associated effects on energy metabolism. For acute exposures to small mono-dispersed particles, it can be concluded there should be little concern regarding their dispersal into the environment for this trophic level. PMID:25740379

  14. Environmental levels, toxicity and human exposure to tributyltin (TBT)-contaminated marine environment. a review. b_antizar@hotmail.com.

    Science.gov (United States)

    Antizar-Ladislao, Blanca

    2008-02-01

    Tributyltin (TBT) is a toxic chemical used for various industrial purposes such as slime control in paper mills, disinfection of circulating industrial cooling waters, antifouling agents, and the preservation of wood. Due to its widespread use as an antifouling agent in boat paints, TBT is a common contaminant of marine and freshwater ecosystems exceeding acute and chronic toxicity levels. TBT is the most significant pesticide in marine and freshwaters in Europe and consequently its environmental level, fate, toxicity and human exposure are of current concern. Thus, the European Union has decided to specifically include TBT compounds in its list of priority compounds in water in order to control its fate in natural systems, due to their toxic, persistent, bioaccumulative and endocrine disruptive characteristics. Additionally, the International Maritime Organization has called for a global treaty that bans the application of TBT-based paints starting 1 of January 2003, and total prohibition by 1 of January 2008. This paper reviews the state of the science regarding TBT, with special attention paid to the environmental levels, toxicity, and human exposure. TBT compounds have been detected in a number of environmental samples. In humans, organotin compounds have been detected in blood and in the liver. As for other persistent organic pollutants, dietary intake is most probably the main route of exposure to TBT compounds for the general population. However, data concerning TBT levels in foodstuffs are scarce. It is concluded that investigations on experimental toxicity, dietary intake, potential human health effects and development of new sustainable technologies to remove TBT compounds are clearly necessary.

  15. Nitrous Oxide Exposure of Health Care Personnel in the Operating Rooms and Intensive Care Units in Hospitals in Macedonia

    Directory of Open Access Journals (Sweden)

    Biljana Eftimova

    2017-10-01

    CONCLUSIONS: Study indicated significant exposure of personal working in substandard ORs in CH – Shtip. Applying proper work practices and maintain control equipment (general ventilation and scavenging systems in operation, could provide for safe work environment.

  16. Bioavailability and Toxicity of Copper, Manganese, and Nickel in Paronychiurus kimi (Collembola), and Biomarker Discovery for Their Exposure.

    Science.gov (United States)

    Son, Jino; Lee, Yun-Sik; Lee, Sung-Eun; Shin, Key-Il; Cho, Kijong

    2017-01-01

    Bioavailability and toxicity of Cu, Mn, and Ni in Paronychiurus kimi were investigated after 28 days of exposure to OECD artificial soil spiked with these metals. Uptake and effect of Cu, Mn, and Ni on the reproduction of P. kimi were related to different metal fractions (water-soluble, 0.01 M CaCl 2 -extractable or porewater metal concentrations). Cu and Mn concentrations in P. kimi increased with increasing Cu and Mn concentrations in the soil, while Ni contents in P. kimi reached a plateau at a concentration higher than 200 mg/kg in soil. Both uptake and juvenile production related well to different metal fractions, suggesting that these metal fractions are suitable for assessing bioavailability and toxicity of metals in P. kimi. When toxicity for reproduction was compared, as reflected by EC 50 values, the order of metal toxicity varied depending upon how exposure concentration was expressed. Moreover, the results of proteomic analysis showed that several proteins involved in the immune system, neuronal outgrowth, and metal ion binding were up-regulated in P. kimi following short-term (7 days) exposure to sublethal level (corresponding to 50% of the EC 50 ) of Cu, Mn, or Ni, respectively. This suggests that the ecotoxicoproteomic approach seems to be a promising tool for early exposure warnings below which significant adverse effects are unlikely to occur. This study demonstrated that a combination of chemical and biological measures can provide information about metal bioavailability and toxicity to which P. kimi has been exposed.

  17. Exposure information in environmental health research: Current opportunities and future directions for particulate matter, ozone, and toxic air pollutants

    Energy Technology Data Exchange (ETDEWEB)

    McKone, Thomas E.; Ryan, P. Barry; Ozkaynak, Haluk

    2007-02-01

    Understanding and quantifying outdoor and indoor sources of human exposure are essential but often not adequately addressed in health-effects studies for air pollution. Air pollution epidemiology, risk assessment, health tracking and accountability assessments are examples of health-effects studies that require but often lack adequate exposure information. Recent advances in exposure modeling along with better information on time-activity and exposure factors data provide us with unique opportunities to improve the assignment of exposures for both future and ongoing studies linking air pollution to health impacts. In September 2006, scientists from the US Environmental Protection Agency (EPA) and the Centers for Disease Control and Prevention (CDC) along with scientists from the academic community and state health departments convened a symposium on air pollution exposure and health in order to identify, evaluate, and improve current approaches for linking air pollution exposures to disease. This manuscript presents the key issues, challenges and recommendations identified by the exposure working group, who used cases studies of particulate matter, ozone, and toxic air pollutant exposure to evaluate health-effects for air pollution. One of the over-arching lessons of this workshop is that obtaining better exposure information for these different health-effects studies requires both goal-setting for what is needed and mapping out the transition pathway from current capabilities to meeting these goals. Meeting our long-term goals requires definition of incremental steps that provide useful information for the interim and move us toward our long-term goals. Another over-arching theme among the three different pollutants and the different health study approaches is the need for integration among alternate exposure assessment approaches. For example, different groups may advocate exposure indicators, biomonitoring, mapping methods (GIS), modeling, environmental media

  18. Exposure of cultured human proximal tubular cells to cadmium, mercury, zinc and bismuth: toxicity and metallothionein induction.

    Science.gov (United States)

    Rodilla, V; Miles, A T; Jenner, W; Hawksworth, G M

    1998-08-14

    The kidney, in particular the proximal convoluted tubule, is a major target site for the toxic effects of various metals. However, little is known about the early effects of these metals after acute exposure in man. In the present study we have evaluated the toxicity of several inorganic metal compounds (CdCl2, HgCl2, ZnCl2, and Bi(NO3)3) and the induction of metallothionein by these compounds in cultured human proximal tubular (HPT) cells for up to 4 days. The results showed that bismuth was not toxic even at the highest dose (100 microM) used, while zinc, cadmium and mercury exhibited varying degrees of toxicity, zinc being the least toxic and mercury the most potent. A significant degree of interindividual variation between the different isolates used in these experiments was also observed. All metals used in the present study induced MT, as revealed by immunocytochemistry. All metals showed maximal induction between 1 and 3 days after treatment. Although a certain amount of constitutive MT was present in the cultures, the intensity of the staining varied with time in culture and between the different isolates studied. No correlation could be made between the intensity of the staining in control cultures (indicating total amount of constitutive MT) and the susceptibility of a given isolate to metal toxicity. Furthermore, no correlation could be made between metal-induced MT and the susceptibility of a given isolate to that particular metal.

  19. Neurophysiological Effects of Chronic Indoor Environmental Toxic Mold Exposure on Children

    Directory of Open Access Journals (Sweden)

    Ebere C. Anyanwu

    2003-01-01

    Full Text Available The phenomenon of building-related diseases is attracting much research interest in recent years because of the extent to which it affects people with compromised immune systems, especially children. In this study, we reported the neurological findings in children who attended our Center because of chronic exposure to toxic molds. Clinical neurological and neurobehavioral questionnaires were administered with the cooperation of the children�s parents. The children then underwent a series of neurophysiological tests including electroencephalogram (EEG, brainstem evoked potential (BAEP, visual evoked potential (VEP, and somatosensory evoked potential (SSEP. The results showed high levels of abnormalities in the analysis of the subjective responses derived from the questionnaires. The EEG examination was abnormal in seven out of ten of the patients compared to the controls with only one in ten with episodes of bihemispheric sharp activity. In all the patients, there was frontotemporal theta wave ativity that seemed to indicate diffuse changes characteristic of metabolic encephalopathies. Also, there was highly marked 1 to 3 Hz delta activity that was asymmetrical in the right hemisphere of the brain in three out of ten patients. The waveforms of BAEP showed abnormalities in 90% of the patients with both 15’ and 31’ check sizes compared to none in the controls. There were significant delays in waveform V in a majority of the patients representing dysfunctional cognitive process and conductive hearing loss in both ears. VEP showed clear abnormalities in four in ten of the patients with P100 amplitudes and latencies decreased bilaterally. In all the patients, there was slowing of conduction in the right tibial at an average of 36.9 ms and there was significant decrease in amplitude of response at the proximal stimulation site. Sensory latencies obtained in the median, ulnar, and sural nerves bilaterally showed abnormalities in five out of ten

  20. Personal and ambient exposures to air toxics in Camden, New Jersey.

    Science.gov (United States)

    Lioy, Paul J; Fan, Zhihua; Zhang, Junfeng; Georgopoulos, Panos; Wang, Sheng-Wei; Ohman-Strickland, Pamela; Wu, Xiangmei; Zhu, Xianlei; Harrington, Jason; Tang, Xiaogang; Meng, Qingyu; Jung, Kyung Hwa; Kwon, Jaymin; Hernandez, Marta; Bonnano, Linda; Held, Joann; Neal, John

    2011-08-01

    Personal exposures and ambient concentrations of air toxics were characterized in a pollution "hot spot" and an urban reference site, both in Camden, New Jersey. The hot spot was the city's Waterfront South neighborhood; the reference site was a neighborhood, about 1 km to the east, around the intersection of Copewood and Davis streets. Using personal exposure measurements, residential ambient air measurements, statistical analyses, and exposure modeling, we examined the impact of local industrial and mobile pollution sources, particularly diesel trucks, on personal exposures and ambient concentrations in the two neighborhoods. Presented in the report are details of our study design, sample and data collection methods, data- and model-analysis approaches, and results and key findings of the study. In summary, 107 participants were recruited from nonsmoking households, including 54 from Waterfront South and 53 from the Copewood-Davis area. Personal air samples were collected for 24 hr and measured for 32 target compounds--11 volatile organic compounds (VOCs*), four aldehydes, 16 polycyclic aromatic hydrocarbons (PAHs), and particulate matter (PM) with an aerodynamic diameter 0.6) was found between benzene and MTBE in both locations. These results suggest that automobile exhausts were the main contributors to benzene and MTBE air pollution in both neighborhoods. Formaldehyde and acetaldehyde concentrations were found to be high in both neighborhoods. Mean (+/- SD) concentrations of formaldehyde were 20.2 +/- 19.5 microg/m3 in Waterfront South and 24.8 +/- 20.8 microg/m3 in Copewood-Davis. A similar trend was observed for the two compounds during the saturation-sampling campaigns. The results indicate that mobile sources (i.e., diesel trucks) had a large impact on formaldehyde and acetaldehyde concentrations in both neighborhoods and that both are aldehyde hot spots. The study also showed that PM2.5, aldehydes, BTEX, and MTBE concentrations in both Waterfront South

  1. Chronic uranium exposure and growth toxicity for phytoplankton. Dose-effect relationship: first comparison of chemical and radiological toxicity

    International Nuclear Information System (INIS)

    Gilbin, R.; Pradines, C.; Garnier-Laplace, J.

    2004-01-01

    The bioavailability of uranium for freshwater organisms, as for other dissolved metals, is closely linked to chemical speciation in solution (U aqueous speciation undergoes tremendous changes in the presence of ligands commonly found in natural waters e.g. carbonate, phosphate, hydroxide and natural organic matter). For the studied chemical domain, short-term uranium uptake experiments have already shown that the free uranyl ion concentration [UO 2 2+ ] is a good predictor of uranium uptake by the green algae Chlamydomonas reinhardtii, as predicted by the Free Ion Activity Model. In agreement with these results, acidic pH and low ligands concentrations in water enhance uranium bioavailability and consequently its potential chronic effects on phytoplankton. Moreover, uranium is known to be both radio-toxic and chemo-toxic. The use of different isotopes of uranium allows to expose organisms to different radiological doses for the same molar concentration: e.g. for a given element concentration (chemical dose), replacing depleted U by U-233 obviously leads to an enhanced radiological delivered dose to organisms (x10 4 ). In this work we established relationships between uranium doses (depleted uranium and 233-U ) and effect on the growth rate of the green algae Chlamydomonas reinhardtii. Uranium bioaccumulation was also monitored. Growth rate was measured both in classical batch (0-72 hrs) and continuous (turbidostat) cultures, the latter protocol allowing medium renewal to diminish exudates accumulation and speciation changes in the medium. The differences in effects will be, if possible, related to the development of defence mechanisms against the formation of reactive oxygen species (forms of glutathione) and the production of phyto-chelatins (small peptides rich in cystein that play an important role in the homeostasis and the detoxication of metals in cells). (author)

  2. Radiation protection requirements for organizations practising mining activities which can bring about exposure of personnel, public, or the environment. Recommendations

    International Nuclear Information System (INIS)

    1999-01-01

    The publication consists of the following articles: (1) Scope of State Office for Nuclear Safety recommendations; (2) Glossary of terms; (3) Radiation protection quantities; (4) General requirements for radiation protection and responsibilities of organizations; (5) Exposure limits; (6) Organizational and technical provisions of radiation protection; (7) Monitoring, measurement, evaluation, and recording of radiation protection-related quantities, parameters, and facts; (8) Utilization of monitoring data. Provisions to keep professional and public exposure within tolerable limits; (9) Decommissioning of workplaces handling ionizing radiation sources; (10) Waste handling; and (11) Transport of material arising from mining activities. The text is supplemented with 5 tabular annexes. (P.A)

  3. Exposure to toxics during pregnancy and childhood and asthma in children: A pilot study

    Directory of Open Access Journals (Sweden)

    Souheil Hallit

    2017-09-01

    Full Text Available Environmental factors, pesticides, alcohol and smoking are linked to asthma in children. The association of toxic substances exposure with asthma has not been evaluated. Our objective is to assess such associations among children aged less than 16 years old. This is a cross-sectional study, conducted between January and May 2015, using a sample of Lebanese students from private schools in Beirut and Mount Lebanon. Out of 700 distributed questionnaires, 527 (75.2% were returned to us. Verbal informed consent was also obtained from all parents prior to participating in the study. A significant association was found between waterpipe smoking and diagnosed asthma (p = 0.003; ORa = 13.25; 95% CI 2.472–71.026. Alcohol during pregnancy, waterpipe smoking during pregnancy and parents respiratory problems significantly increased the risk of respiratory problems by approximately 5 times, 6 times and 2 times respectively (p = 0.016; ORa = 4.889; 95% CI 1.339–17.844, p = 0.021; ORa = 6.083; 95% CI 1.314–28.172, p = 0.004; ORa = 1.748; 95% CI 1.197–2.554 respectively. Waterpipe smoking, alcohol during pregnancy, recurrent otitis and humidity at home seem to be significantly correlated with asthma in children. Spreading awareness by health care professionals is needed to permit a reduction of the prevalence of these allergic diseases, especially asthma, in children.

  4. Exposure to potentially toxic hydrocarbons and halocarbons released from the dialyzer and tubing set during hemodialysis.

    Science.gov (United States)

    Lee, Hyun Ji Julie; Meinardi, Simone; Pahl, Madeleine V; Vaziri, Nostratola D; Blake, Donald R

    2012-10-01

    Although much is known about the effect of chronic kidney failure and dialysis on the composition of solutes in plasma, little is known about their impact on the composition of gaseous compounds in exhaled breath. This study was designed to explore the effect of uremia and the hemodialysis (HD) procedure on the composition of exhaled breath. Breath samples were collected from 10 dialysis patients immediately before, during, and after a dialysis session. To determine the potential introduction of gaseous compounds from dialysis components, gasses emitted from dialyzers, tubing set, dialysate, and water supplies were collected. Prospective cohort study. 10 HD patients and 10 age-matched healthy individuals. Predictors include the dialyzers, tubing set, dialysate, and water supplies before, during, and after dialysis. Changes in the composition of exhaled breath. A 5-column/detector gas chromatography system was used to measure hydrocarbon, halocarbon, oxygenate, and alkyl nitrate compounds. Concentrations of 14 hydrocarbons and halocarbons in patients' breath rapidly increased after the onset of the HD treatment. All 14 compounds and 5 others not found in patients' breath were emitted from the dialyzers and tubing sets. Contrary to earlier reports, exhaled breath ethane concentrations in our dialysis patients were virtually unchanged during the HD treatment. Single-center study with a small sample size may limit the generalizability of the findings. The study documented the release of several potentially toxic hydrocarbons and halocarbons to patients from the dialyzer and tubing sets during the HD procedure. Because long-term exposure to these compounds may contribute to the morbidity and mortality in dialysis population, this issue should be considered in the manufacturing of the new generation of dialyzers and dialysis tubing sets. Copyright © 2012 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  5. In Vivo acrylamide exposure may cause severe toxicity to mouse oocytes through its metabolite glycidamide.

    Directory of Open Access Journals (Sweden)

    Duru Aras

    Full Text Available High acrylamide (ACR content in heat-processed carbohydrate-rich foods, as well as roasted products such as coffee, almonds etc., has been found to be as a risk factor for carcinogenicity and genotoxicity by The World Health Organization. Glycidamide (GLY, the epoxide metabolite of ACR, is processed by the cytochrome P-450 enzyme system and has also been found to be a genotoxic agent. The aim of this study was to determine whether ACR and/or GLY have any detrimental effect on the meiotic cell division of oocytes. For this purpose, germinal vesicle-stage mouse oocytes were treated with 0, 100, 500, or 1000 μM ACR or 0, 25, or 250 μM GLY in vitro. In vivo experiments were performed after an intraperitoneal injection of 25 mg/kg/day ACR of female BALB/c mice for 7 days. The majority of in vitro ACR-treated oocytes reached the metaphase-II stage following 18 hours of incubation, which was not significantly different from the control group. Maturation of the oocytes derived from in vivo ACR-treated mice was impaired significantly. Oocytes, reaching the M-II stage in the in vivo ACR-treated group, were characterized by a decrease in meiotic spindle mass and an increase in chromosomal disruption. In vitro GLY treatment resulted in the degeneration of all oocytes, indicating that ACR toxicity on female germ cells may occur through its metabolite, GLY. Thus, ACR exposure must be considered, together with its metabolite GLY, when female fertility is concerned.

  6. The Toxic Exposure Surveillance System (TESS): Risk assessment and real-time toxicovigilance across United States poison centers

    International Nuclear Information System (INIS)

    Watson, William A.; Litovitz, Toby L.; Belson, Martin G.; Funk Wolkin, Amy B.; Patel, Manish; Schier, Joshua G.; Reid, Nicole E.; Kilbourne, Edwin; Rubin, Carol

    2005-01-01

    The Toxic Exposure Surveillance System (TESS) is a uniform data set of US poison centers cases. Categories of information include the patient, the caller, the exposure, the substance(s), clinical toxicity, treatment, and medical outcome. The TESS database was initiated in 1985, and provides a baseline of more than 36.2 million cases through 2003. The database has been utilized for a number of safety evaluations. Consideration of the strengths and limitations of TESS data must be incorporated into data interpretation. Real-time toxicovigilance was initiated in 2003 with continuous uploading of new cases from all poison centers to a central database. Real-time toxicovigilance utilizing general and specific approaches is systematically run against TESS, further increasing the potential utility of poison center experiences as a means of early identification of potential public health threats

  7. The Toxic Exposure Surveillance System (TESS): risk assessment and real-time toxicovigilance across United States poison centers.

    Science.gov (United States)

    Watson, William A; Litovitz, Toby L; Belson, Martin G; Wolkin, Amy B Funk; Patel, Manish; Schier, Joshua G; Reid, Nicole E; Kilbourne, Edwin; Rubin, Carol

    2005-09-01

    The Toxic Exposure Surveillance System (TESS) is a uniform data set of US poison centers cases. Categories of information include the patient, the caller, the exposure, the substance(s), clinical toxicity, treatment, and medical outcome. The TESS database was initiated in 1985, and provides a baseline of more than 36.2 million cases through 2003. The database has been utilized for a number of safety evaluations. Consideration of the strengths and limitations of TESS data must be incorporated into data interpretation. Real-time toxicovigilance was initiated in 2003 with continuous uploading of new cases from all poison centers to a central database. Real-time toxicovigilance utilizing general and specific approaches is systematically run against TESS, further increasing the potential utility of poison center experiences as a means of early identification of potential public health threats.

  8. Preliminary results from a survey of U.S. Forest Service wildfire managers' attitudes toward aviation personnel exposure and risk

    Science.gov (United States)

    Matthew Wibbenmeyer; Michael Hand; David Calkin

    2012-01-01

    The U.S. Department of Agriculture, Forest Service (USFS) has, in recent years, increasingly emphasized the importance of safety to its employees, but wildfire management remains a risky endeavor. While wildfire management decisions affecting safety and exposure of firefighters to the wildland fire environment may be aided by decision support tools such the Wildfire...

  9. Air Force Health Study. An Epidemiologic Investigation of Health Effects in Air Force Personnel Following Exposure to Herbicides. Volume 3

    Science.gov (United States)

    1991-03-01

    exposure. The perceived exposed cohort scored significantly higher on NLMPI scales F, hypochondriasis , depression, paranoia, psychasthenia...R variables, the Ranch Hands had marginally more abnormalities than the Comparisons for depression, somatization , and an index of the general severity...compulsive behavior, paranoid ideation, phobic anxiety, psychoticism, and somatization . Three global indices also were analyzed: the global severity index

  10. A Decade of War: Prospective Trajectories of Posttraumatic Stress Disorder Symptoms Among Deployed US Military Personnel and the Influence of Combat Exposure.

    Science.gov (United States)

    Donoho, Carrie J; Bonanno, George A; Porter, Ben; Kearney, Lauren; Powell, Teresa M

    2017-12-15

    Posttraumatic stress disorder (PTSD) is a common psychiatric disorder among service members and veterans. The clinical course of PTSD varies between individuals, and patterns of symptom development have yet to be clearly delineated. Previous studies have been limited by convenience sampling, short follow-up periods, and the inability to account for combat-related trauma. To determine the trajectories of PTSD symptoms among deployed military personnel with and without combat exposure, we used data from a population-based representative sample of 8,178 US service members who participated in the Millennium Cohort Study from 2001 to 2011. Using latent growth mixture modeling, trajectories of PTSD symptoms were determined in the total sample, as well as in individuals with and without combat exposure, respectively. Overall, 4 trajectories of PTSD were characterized: resilient, pre-existing, new-onset, and moderate stable. Across all trajectories, combat-deployed service members diverged from non-combat-deployed service members, even after a single deployment. The former also generally had higher PTSD symptoms. Based on the models, nearly 90% of those without combat exposure remained resilient over the 10-year period, compared with 80% of those with combat exposure. Findings demonstrate that although the clinical course of PTSD symptoms shows heterogeneous patterns of development, combat exposure is uniformly associated with poor mental health. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  11. Future research needs associated with the assessment of potential human health risks from exposure to toxic ambient air pollutants

    DEFF Research Database (Denmark)

    Möller, Lennart; Schuetzle, Dennis; Autrup, Herman

    1994-01-01

    of identification and quantification of toxics in source emissions and ambient air, atmospheric transport and chemistry, exposure level assessment, the development of improved in vitro bioassays, biomarker development, the development of more accurate epidemiological methodologies, and risk quantification...... techniques. Studies are described that will be necessary to assess and reduce the level of uncertainties associated with each step of the risk assessment process. International collaborative research efforts between industry and government organizations are recommended as the most effective way to carry out...

  12. Development and demonstration of surveillance and diagnostics of rotating machinery for reducing radiation exposure to nuclear power plant personnel: Final report

    International Nuclear Information System (INIS)

    Allen, J.W.; Bohanick, J.S.

    1988-01-01

    This program was designed to reduce radiation exposure to power plant personnel resulting from inspection, maintenance, and repair of rotating equipment. The new rotating machinery monitoring system for this program was installed at GGNS during August 1983. This document provides a functional description of the hardware and software that comprise the system and discusses the application of the monitoring system to achieving overall program goals. The analyses of the monitored rotating machinery during the plant startup phase and after the plant's first fuel cycle are presented in addition to the radiation dose reduction which occurred as a direct and indirect result of the RMSS. The dose reduction program at GGNS is reviewed and recommendations made to incorporate this program with the RMSS. 28 refs., 64 figs., 43 tabs

  13. Pulmonary toxicity following exposure to a tile coating product containing alkylsiloxanes

    DEFF Research Database (Denmark)

    Duch, P.; Nørgaard, A. W.; Hansen, J. S.

    2014-01-01

    Context. Coating products are widely used for making surfaces water and dirt repellent. However, on several occasions the use of these products has been associated with lung toxicity. Objective. In the present study, we evaluated the toxic effects of an aerosolized tile-coating product. Methods...

  14. Personnel dose assignment practices

    International Nuclear Information System (INIS)

    Fix, J.J.

    1993-04-01

    Implementation of DOE N 5480.6 Radiological Control Manual Article 511(3) requirements, to minimize the assignment of personnel dosimeters, should be done only under a broader context ensuring that capabilities are in place to monitor and record personnel exposure both for compliance and for potential litigation. As noted in NCRP Report No. 114, personnel dosimetry programs are conducted to meet four major objectives: radiation safety program control and evaluation; regulatory compliance; epidemiological research; and litigation. A change to Article 511(3) is proposed that would require that minimizing the assignment of personnel dosimeters take place only following full evaluation of overall capabilities (e.g., access control, area dosimetry, etc.) to meet the NCRP objectives

  15. Hanging drop: an in vitro air toxic exposure model using human lung cells in 2D and 3D structures.

    Science.gov (United States)

    Liu, Faye F; Peng, Cheng; Escher, Beate I; Fantino, Emmanuelle; Giles, Cindy; Were, Stephen; Duffy, Lesley; Ng, Jack C

    2013-10-15

    Using benzene as a candidate air toxicant and A549 cells as an in vitro cell model, we have developed and validated a hanging drop (HD) air exposure system that mimics an air liquid interface exposure to the lung for periods of 1h to over 20 days. Dose response curves were highly reproducible for 2D cultures but more variable for 3D cultures. By comparing the HD exposure method with other classically used air exposure systems, we found that the HD exposure method is more sensitive, more reliable and cheaper to run than medium diffusion methods and the CULTEX(®) system. The concentration causing 50% of reduction of cell viability (EC50) for benzene, toluene, p-xylene, m-xylene and o-xylene to A549 cells for 1h exposure in the HD system were similar to previous in vitro static air exposure. Not only cell viability could be assessed but also sub lethal biological endpoints such as DNA damage and interleukin expressions. An advantage of the HD exposure system is that bioavailability and cell concentrations can be derived from published physicochemical properties using a four compartment mass balance model. The modelled cellular effect concentrations EC50cell for 1h exposure were very similar for benzene, toluene and three xylenes and ranged from 5 to 15 mmol/kgdry weight, which corresponds to the intracellular concentration of narcotic chemicals in many aquatic species, confirming the high sensitivity of this exposure method. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Identifying inequitable exposure to toxic air pollution in racialized and low-income neighbourhoods to support pollution prevention

    Directory of Open Access Journals (Sweden)

    Suzanne Kershaw

    2013-05-01

    Full Text Available Numerous environmental justice studies have confirmed a relationship between population characteristics such as low-income or minority status and the location of environmental health hazards. However, studies of the health risks from exposure to harmful substances often do not consider their toxicological characteristics. We used two different methods, the unit-hazard and the distance-based approach, to evaluate demographic and socio-economic characteristics of the population residing near industrial facilities in the City of Toronto, Canada. In addition to the mass of air emissions obtained from the national pollutant release inventory (NPRI, we also considered their toxicity using toxic equivalency potential (TEP scores. Results from the unit-hazard approach indicate no significant difference in the proportion of low-income individuals living in host versus non-host census tracts (t(107 = 0.3, P = 0.735. However, using the distance-based approach, the proportion of low-income individuals was significantly higher (+5.1%, t(522 = 6.0, P <0.001 in host tracts, while the indicator for “racialized” communities (“visible minority” was 16.1% greater (t(521 = 7.2, P <0.001 within 2 km of a NPRI facility. When the most toxic facilities by non-carcinogenic TEP score were selected, the rate of visible minorities living near the most toxic NPRI facilities was significantly higher (+12.9%, t(352 = 3.5, P = 0.001 than near all other NPRI facilities. TEP scores were also used to identify areas in Toronto that face a double burden of poverty and air toxics exposure in order to prioritise pollution prevention.

  17. Subchronic toxicity of Nile tilapia with different exposure routes to Microcystis aeruginosa: Histopathology, liver functions, and oxidative stress biomarkers

    Directory of Open Access Journals (Sweden)

    H. M. R. Abdel-Latif

    2017-08-01

    Full Text Available Background: Toxic cyanobacterial blooms (Microcystis aeruginosa contains microcystins [MCs] have been reported to induce clinicopathological alterations as well as different oxidative stress in aquatic biota. Aim: Three-week subchronic exposure experiment was carried out on Nile tilapia, to determine their effects on fish behavior, tissues, liver functions, antioxidant enzymes, and lipid peroxidation. Materials and Methods: Fish were exposed to four main treatments; orally fed diet plus toxic cells of M. aeruginosa (containing 3500 μg/g MC-LR, immersion in 500 μg MC-LR/L, intraperitoneal injection of M. aeruginosa MC-LR with a dose of 0.1 ml of extracted toxin at a dose of 200 μg/kg bwt, and the fourth one served as a control group, then the fish were sacrificed at the end of 3rd week of exposure. Results: The results revealed no recorded mortality with obvious behavioral changes and an enlarged liver with the congested gall bladder. Histopathology demonstrated fragmentation, hyalinization, and necrosis of the subcutaneous musculature marked fatty degeneration, and vacuolation of hepatopancreatic cells with adhesion of the secondary gill lamellae associated with severe leukocytic infiltration. Furthermore, liver functions enzymes (aspartate aminotransferase and alanine aminotransferase, and the activities of glutathione peroxidase, glutathione reductase, lipid peroxidase, and catalase enzymes were significantly increased in all treatments starting from the 2nd week as compared to the control levels. Conclusion: In this context, the study addresses the possible toxicological impacts of toxic M. aeruginosa contain MC-LR to Nile tilapia, and the results investigated that MC-LR is toxic to Nile tilapia in different routes of exposure as well as different doses.

  18. Retinal toxicity associated with chronic exposure to hydroxychloroquine and its ocular screening. Review.

    Science.gov (United States)

    Geamănu Pancă, A; Popa-Cherecheanu, A; Marinescu, B; Geamănu, C D; Voinea, L M

    2014-09-15

    Hydroxychloroquine sulfate (HCQ, Plaquenil) is an analogue of chloroquine (CQ), an antimalarial agent, used for the treatment of systemic lupus erythematosus, rheumatoid arthritis and other autoimmune disorders. Its use has been associated with severe retinal toxicity, requiring a discontinuation of therapy. Because it presents potential secondary effects including irreversible maculopathy, knowledge of incidence, risk factors, drug toxicity and protocol screening of the patients it represents important data for the ophthalmologists. Thus, it is imperative that rheumatologists, medical internists and ophthalmologists are aware of the toxicity from hydroxychloroquine they should also be careful to minimize its occurrence and effects.

  19. Nuclear Test Personnel Review

    Science.gov (United States)

    FOIA Electronic Reading Room Privacy Impact Assessment DTRA No Fear Act Reporting Nuclear Test Personnel Review NTPR Fact Sheets NTPR Radiation Dose Assessment Documents US Atmospheric Nuclear Test History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak

  20. Lung toxicity determination by in vitro exposure at the air liquid interface with an integrated online dose measurement

    International Nuclear Information System (INIS)

    Muelhopt, Sonja; Paur, H-R; Diabate, S; Weiss, C; Krebs, T

    2009-01-01

    Epidemiological studies show an association between the concentration of ultrafine particles in the atmosphere and the rate of mortality or morbidity due to respiratory and cardiovascular diseases. For the quantitative assessment of the toxicity of airborne nanoparticles the dose-response relationship is tested in in vitro test systems using bioassays of cell cultures as sensor. For the air-liquid interface exposure of cell cultures towards aerosols the Karlsruhe exposure system was developed. The human lung cell cultures are exposed in VITROCELL (registered) system modules with a constant flow of the conditioned aerosol. After exposure the cells are analyzed to measure the biological responses such as viability, inflammatory or oxidative stress. For the determination of the dose response relationship the accurate knowledge of the deposited particle mass is essential. A new online method is developed in the Karlsruhe exposure system: the sensor of a quartz crystal microbalance is placed in an exposure chamber instead of the membrane insert and exposed to the aerosol in the same way as the cell cultures. The deposited mass per area unit is monitored as a function of exposure time showing a linear relationship for a constant aerosol flow with defined particle concentration. A comparison of this new dose signal to a dosimetry method using fluorescein sodium particles shows a very good correlation between the sensor signal of the quartz crystal microbalance and the deposited mass on the membranes shown by spectroscopy. This system for the first time provides an online dose measurement for in vitro experiments with nanoparticles.

  1. Toxic Exposure Surveillance System (TESS)-based characterization of U.S. non-native venomous snake exposures, 1995-2004.

    Science.gov (United States)

    Seifert, Steven A; Oakes, Jennifer A; Boyer, Leslie V

    2007-01-01

    Non-native (exotic) snake exposures in the United States have not been systematically characterized. The Toxic Exposure Surveillance System (TESS) database of the American Association of Poison Control Centers was analyzed to quantify the number and types, demographic associations, clinical presentations, managements and outcomes, and the health resource utilization of non-native snake exposures. From 1995 through 2004, there were 399 non-native exposures in the TESS database. Of these, 350 snakes (87%) were identified by genus and species, comprising at least 77 different varieties. Roughly equal percentages of snakes originated in Asia, Africa and Latin America, with a smaller number from the Middle-East, Australia, and Europe. Nearly half were viperids and a little more than a third were elapids. The vast majority of exposed individuals were adults. However, almost 15% were aged 17 years or less, and almost 7% were children aged 5 years or younger. Eighty-four percent were males. The vast majority of exposures occurred at the victim's own residence. Over 50% were evaluated at a healthcare facility, with 28.7% admitted to an ICU. Overall, 26% of patients were coded as receiving antivenom treatment. Coded outcomes were similar between viperid and elapid envenomations. There were three deaths, two involving viperid snakes and one elapid. Enhancements to the TESS database are required for better precision in and more complete characterization of non-native snake envenomations.

  2. Steroid Hydroxylase Activities as Noninvasive Biomarkers of Toxicant Exposure and Effect

    National Research Council Canada - National Science Library

    Leblanc, Gerald

    1997-01-01

    .... The overall goal of this research project was to test the hypothesis that changes in the metabolic elimination of the steroid hormone testosterone could serve as a non-invasive biomarker of toxicant...

  3. Effect of Prolonged Exposure Therapy Delivered Over 2 Weeks vs 8 Weeks vs Present-Centered Therapy on PTSD Symptom Severity in Military Personnel: A Randomized Clinical Trial.

    Science.gov (United States)

    Foa, Edna B; McLean, Carmen P; Zang, Yinyin; Rosenfield, David; Yadin, Elna; Yarvis, Jeffrey S; Mintz, Jim; Young-McCaughan, Stacey; Borah, Elisa V; Dondanville, Katherine A; Fina, Brooke A; Hall-Clark, Brittany N; Lichner, Tracey; Litz, Brett T; Roache, John; Wright, Edward C; Peterson, Alan L

    2018-01-23

    Effective and efficient treatment is needed for posttraumatic stress disorder (PTSD) in active duty military personnel. To examine the effects of massed prolonged exposure therapy (massed therapy), spaced prolonged exposure therapy (spaced therapy), present-centered therapy (PCT), and a minimal-contact control (MCC) on PTSD severity. Randomized clinical trial conducted at Fort Hood, Texas, from January 2011 through July 2016 and enrolling 370 military personnel with PTSD who had returned from Iraq, Afghanistan, or both. Final follow-up was July 11, 2016. Prolonged exposure therapy, cognitive behavioral therapy involving exposure to trauma memories/reminders, administered as massed therapy (n = 110; 10 sessions over 2 weeks) or spaced therapy (n = 109; 10 sessions over 8 weeks); PCT, a non-trauma-focused therapy involving identifying/discussing daily stressors (n = 107; 10 sessions over 8 weeks); or MCC, telephone calls from therapists (n = 40; once weekly for 4 weeks). Outcomes were assessed before and after treatment and at 2-week, 12-week, and 6-month follow-up. Primary outcome was interviewer-assessed PTSD symptom severity, measured by the PTSD Symptom Scale-Interview (PSS-I; range, 0-51; higher scores indicate greater PTSD severity; MCID, 3.18), used to assess efficacy of massed therapy at 2 weeks posttreatment vs MCC at week 4; noninferiority of massed therapy vs spaced therapy at 2 weeks and 12 weeks posttreatment (noninferiority margin, 50% [2.3 points on PSS-I, with 1-sided α = .05]); and efficacy of spaced therapy vs PCT at posttreatment. Among 370 randomized participants, data were analyzed for 366 (mean age, 32.7 [SD, 7.3] years; 44 women [12.0%]; mean baseline PSS-I score, 25.49 [6.36]), and 216 (59.0%) completed the study. At 2 weeks posttreatment, mean PSS-I score was 17.62 (mean decrease from baseline, 7.13) for massed therapy and 21.41 (mean decrease, 3.43) for MCC (difference in decrease, 3.70 [95% CI,0.72 to 6.68]; P = .02

  4. Plant exposure chambers for study of toxic chemical-plant interactions (journal version)

    International Nuclear Information System (INIS)

    McFarlane, J.C.; Pfleeger, T.

    1987-01-01

    Chambers for the study of plant uptake and phytotoxicity of toxic, radio-labeled chemicals are described. The chambers are designed to meet the criteria of continuously stirred tank reactors while providing containment for toxic chemicals. They are computer managed and operated within a controlled-environment room. Besides providing controlled conditions within the contained spaces, continuous measurements are made of various environmental parameters and plant transpiration, net photosynthesis, and dark respiration in up to 18 separate chambers

  5. Mechanistic Approach to Understanding the Toxicity of the Azole Fungicide Triadimefon to a Nontarget Aquatic Insect and Implications for Exposure Assessment

    Science.gov (United States)

    We utilized mechanistic and stereoselective based in vitro metabolism assays and sublethal exposures of triadimefon to gain insight into the extent of carbonyl reduction and the toxic mode of action of triadimefon with black fly (Diptera: Simuliidae) larvae.

  6. Parental exposure to heavy fuel oil induces developmental toxicity in offspring of the sea urchin Strongylocentrotus intermedius.

    Science.gov (United States)

    Duan, Meina; Xiong, Deqi; Yang, Mengye; Xiong, Yijun; Ding, Guanghui

    2018-05-03

    The present study investigated the toxic effects of parental (maternal/paternal) exposure to heavy fuel oil (HFO) on the adult reproductive state, gamete quality and development of the offspring of the sea urchin Strongylocentrotus intermedius. Adult sea urchins were exposed to effluents from HFO-oiled gravel columns for 7 days to simulate an oil-contaminated gravel shore, and then gametes of adult sea urchins were used to produce embryos to determine developmental toxicity. For adult sea urchins, no significant difference in the somatic size and weight was found between the various oil loadings tested, while the gonad weight and gonad index were significantly decreased at higher oil loadings. The spawning ability of adults and fecundity of females significantly decreased. For gametes, no effect was observed on the egg size and fertilization success in any of the groups. However, a significant increase in the percentage of anomalies in the offspring was observed and then quantified by an integrative toxicity index (ITI) at 24 and 48 h post fertilization. The offspring from exposed parents showed higher ITI values with more malformed embryos. The results confirmed that parental exposure to HFO can cause adverse effects on the offspring and consequently affect the recruitment and population maintenance of sea urchins. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. [The umbilical blood levels of lead and some other toxic metals as a biomarker of environment-induced exposure].

    Science.gov (United States)

    Privalova, L I; Malykh, O L; Matiukhina, G V; Gnezdilova, S V

    2007-01-01

    Groups of pregnant women, which made up in Revda, Pervouralsk, Krasnouralsk, and Verkh-Isetsky District of Yekaterinburg, were studied. Tests of umbilical blood samples (UB) for the levels of calcium, iron, chromium, manganese, zinc, nickel, cadmium, lead, arsenic, copper, and mercury have established that the mean concentration of lead and the proportion of samples with elevated UB lead concentrations depend on how close the residential area is located to the major industrial source of emission of this toxic metal into ambient air. This correlation is less marked for other metals or it is not found. The particular position of lead is likely to be explained by the fact that it is entirely foreign to an organism and by the comparative unimportance of a contribution of the sources of exposure to this metal, which are unassociated with man-caused environmental and food pollution. As far as other metals are concerned, the situation is complicated by the fact that they are not only toxic, but when upon minor exposures, also essential biotrace elements with controlled and interdependent toxic kinetics. It is also shown that when a pregnant woman takes a complex of biological protectors promoting a reduction in her body's levels of lead, its concentrations in her body, its UB concentration is much lower than such a bioprophylactic effect is absent.

  8. Differential protein expression of hepatic cells associated with MeHg exposure: deepening into the molecular mechanisms of toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Cuello, Susana; Madrid, Yolanda; Luque-Garcia, Jose L.; Camara, Carmen [Complutense University of Madrid, Department of Analytical Chemistry, Faculty of Chemistry, Madrid (Spain); Ramos, Sonia [Institute of Food Science, Technology and Nutrition, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain)

    2012-08-15

    Understanding the molecular mechanisms underlying MeHg toxicity and the way in which this molecule interacts with living organisms is a critical point since MeHg represents a well-known risk to ecosystems and human health. We used a quantitative proteomic approach based on stable isotopic labeling by amino acids in cell culture in combination with SDS-PAGE and nanoflow LC-ESI-LTQ for analyzing the differential protein expression of hepatic cells associated to MeHg exposure. Seventy-eight proteins were found de-regulated by more than 1.5-fold. We identified a number of proteins involved in different essential biological processes including apoptosis, mitochondrial dysfunction, cellular trafficking and energy production. Among these proteins, we found several molecules whose de-regulation has been already related to MeHg exposure, thus confirming the usefulness of our discovery approach, and new ones that helped to gain a deeper insight into the biomolecular mechanisms related to MeHg-induced toxicity. Overexpression of several HSPs and the proteasome 26S subunit itself showed the proteasome system as a molecular target of toxic MeHg. As for the interaction networks, the top ranked was the nucleic acid metabolism, where many of the identified de-regulated proteins are involved. (orig.)

  9. Personnel Preparation.

    Science.gov (United States)

    Fair, George, Ed.; Stodden, Robert, Ed.

    1981-01-01

    Three articles comprise a section on personnel preparation in vocational education. Articles deal with two inservice programs in career/vocational education for the handicapped and a project to train paraprofessionals to assist special educators in vocational education. (CL)

  10. Maintaining radiation exposures as low as reasonably achievable (ALARA) for dental personnel operating portable hand-held x-ray equipment.

    Science.gov (United States)

    McGiff, Thomas J; Danforth, Robert A; Herschaft, Edward E

    2012-08-01

    Clinical experience indicates that newly available portable hand-held x-ray units provide advantages compared to traditional fixed properly installed and operated x-ray units in dental radiography. However, concern that hand-held x-ray units produce higher operator doses than fixed x-ray units has caused regulatory agencies to mandate requirements for use of hand-held units that go beyond those recommended by the manufacturer and can discourage the use of this technology. To assess the need for additional requirements, a hand-held x-ray unit and a pair of manikins were used to measure the dose to a simulated operator under two conditions: exposures made according to the manufacturer's recommendations and exposures made according to manufacturer's recommendation except for the removal of the x-ray unit's protective backscatter shield. Dose to the simulated operator was determined using an array of personal dosimeters and a pair of pressurized ion chambers. The results indicate that the dose to an operator of this equipment will be less than 0.6 mSv y⁻¹ if the device is used according to the manufacturer's recommendations. This suggests that doses to properly trained operators of well-designed, hand-held dental x-ray units will be below 1.0 mSv y⁻¹ (2% of the annual occupational dose limit) even if additional no additional operational requirements are established by regulatory agencies. This level of annual dose is similar to those reported as typical dental personnel using fixed x-ray units and appears to satisfy the ALARA principal for this class of occupational exposures.

  11. Assessment of mechanisms of metal-induced reproductive toxicity in aquatic species as a biomarker of exposure

    International Nuclear Information System (INIS)

    Anderson, M.; George, W.; Sikka, S.; Kamath, B.; Preslan, J.; Agrawal, K.; Rege, A.

    1993-01-01

    This project is designed to identify heavy metals and organic contaminants of concern which could impact on the biota in the Louisiana wetlands by assessment of uptake and bioaccumulation of contaminants and their effects on reproductive processes as biomarkers of exposure. Heavy metals (lead, cadmium, cobalt, and mercury) have been demonstrated to have toxic effects on reproduction in mammals and several aquatic species. Hexachlorobenzene (HCB) is an persistent environmental contaminant which has been measured in human serum, fat, semen, and follicular fluid. HCB has been shown to be a reproductive toxin in rats and primates. Polychlorinated biphenyls (PCBs) are prevalent chlorinated hydrocarbons currently contaminating our environment. PCBs resist degradation and are insoluble in water; however, they bioaccumulate in aquatic species. Disturbances of the reproductive systems are not only sensitive indicators of toxicity but threatens the propagation of a species

  12. Safety Evaluation of Potential Toxic Metals Exposure from Street Foods Consumed in Mid-West Nigeria

    Directory of Open Access Journals (Sweden)

    O. C. Ekhator

    2017-01-01

    Full Text Available Objective. Street-vended foods offer numerous advantages to food security; nevertheless, the safety of street food should be considered. This study has investigated the level of potential toxic metal (Pb, Cd, Hg, Sb, Mn, and Al contamination among street-vended foods in Benin City and Umunede. Methods. Twenty street food samples were purchased from vendors at bus stops. Metals were analyzed with atomic absorption spectrophotometry. The methods developed by the US EPA were employed to evaluate the potential health risk of toxic metals. Results. The concentrations of the toxic metals in mg/kg were in the range of Pb (0.014–1.37, Cd (0.00–0.00017, Hg (0.00–0.00014, Sb (0.00–0.021, Mn (0.00–0.012, and Al (0.00–0.22. All the toxic metals except Pb were below permissible limit set by WHO, EU, and USEPA. The daily intake, hazard quotient, and hazard index of all toxic metals except for Pb in some street foods were below the tolerable daily intake and threshold value of 1, indicating an insignificant health risk. Total cancer risk was within the priority risk level of 1.0E-04 but higher than the acceptable risk level of 1E-06. Conclusion. Consumption of some of these street foods is of public health concern.

  13. Exposure to sennoside-digoxin interaction and risk of digoxin toxicity: a population-based nested case-control study.

    Science.gov (United States)

    Wang, Meng-Ting; Li, I-Hsun; Lee, Wan-Ju; Huang, Tien-Yu; Leu, Hsin-Bang; Chan, Agnes L F

    2011-11-01

    Digoxin is an important medication for heart failure (HF) patients and sennosides are widely used to treat constipation. Recently, safety concerns have been raised about a possible interaction between sennosides and digoxin, an issue that has not been studied empirically. This study therefore aimed to evaluate whether exposure to sennoside-digoxin interaction is associated with an increased risk of digoxin toxicity. This was a population-based nested case-control study that analysed data obtained from the Taiwan National Health Insurance Research Database between 1 January 2001 and 31 December 2004. All HF patients treated with digoxin for the first time were included as the study cohort. Of these, cases were identified as subjects hospitalized for digoxin toxicity (International Classification of Diseases, Ninth Revision, Clinical Modification, ICD-9-CM 972.1), and matched to randomly selected controls. Use of sennosides was compared between the two groups. Odds ratios (ORs) were employed to quantify the risk associated with exposure to sennoside-digoxin interaction by conditional logistic regression. The study cohort comprised 222,527 HF patients, of whom 524 were identified as cases and 2,502 as matched controls. Use of sennosides during the 14 days preceding the index date was found to be associated with a 1.61-fold increased risk of digoxin toxicity [95% confidence interval (CI) = 1.15, 2.25]. Additionally, a greater risk was observed for sennosides prescribed at an average daily dose ≥ 24 mg (adjusted OR = 1.93; 95% CI = 1.27, 2.94). The combined use of sennosides and digoxin was found to be associated with a modest increased risk of digoxin toxicity in HF patients.

  14. Comparison between two clones of Daphnia magna: effects of multigenerational cadmium exposure on toxicity, individual fitness, and biokinetics.

    Science.gov (United States)

    Guan, Rui; Wang, Wen-Xiong

    2006-03-10

    We investigated the effects of genotype (two different clones) and multigenerational Cd-exposure history on Cd toxicity, individual fitness, and biokinetics in populations of a freshwater cladoceran Daphnia magna. The adults of the tolerant (T) clone had longer mean-survival-time than the sensitive (S) clone in both control groups (without Cd-exposure) and continuous Cd-exposure groups, but the two clones showed comparable resistances to acute Cd stress in the recovery groups. The body concentration of metallothionein (MT) played a critical role in handling Cd stress, which mainly accounted for the significant difference between the two clones in terms of survival distribution. High comparability of these two clones in individual fitness parameters and biokinetics suggested that these parameters are unlikely driven by genetic variation. For each specific clone, continuous Cd-exposure inhibited the animal growth, elevated the MT induction, and increased the Cd uptake rate (ingestion rate, assimilation efficiency from dietary phase, and uptake rate from dissolved phase), all of which enhanced the weight-specific Cd accumulation in daphnids' bodies. The strong dependence of biokinetic parameters on environmental factors (e.g., food concentrations, pH, dissolved or dietary metal concentration, and metal exposure histories) rather than on genotypes implied the great potential of using biokinetics in inter-lab comparisons and environmental risk assessments.

  15. Comparison between two clones of Daphnia magna: Effects of multigenerational cadmium exposure on toxicity, individual fitness, and biokinetics

    International Nuclear Information System (INIS)

    Guan Rui; Wang Wenxiong

    2006-01-01

    We investigated the effects of genotype (two different clones) and multigenerational Cd-exposure history on Cd toxicity, individual fitness, and biokinetics in populations of a freshwater cladoceran Daphnia magna. The adults of the tolerant (T) clone had longer mean-survival-time than the sensitive (S) clone in both control groups (without Cd-exposure) and continuous Cd-exposure groups, but the two clones showed comparable resistances to acute Cd stress in the recovery groups. The body concentration of metallothionein (MT) played a critical role in handling Cd stress, which mainly accounted for the significant difference between the two clones in terms of survival distribution. High comparability of these two clones in individual fitness parameters and biokinetics suggested that these parameters are unlikely driven by genetic variation. For each specific clone, continuous Cd-exposure inhibited the animal growth, elevated the MT induction, and increased the Cd uptake rate (ingestion rate, assimilation efficiency from dietary phase, and uptake rate from dissolved phase), all of which enhanced the weight-specific Cd accumulation in daphnids' bodies. The strong dependence of biokinetic parameters on environmental factors (e.g., food concentrations, pH, dissolved or dietary metal concentration, and metal exposure histories) rather than on genotypes implied the great potential of using biokinetics in inter-lab comparisons and environmental risk assessments

  16. Suspended particles only marginally reduce pyrethroid toxicity to the freshwater invertebrate Gammarus pulex (L.) during pulse exposure.

    Science.gov (United States)

    Rasmussen, Jes Jessen; Cedergreen, Nina; Kronvang, Brian; Andersen, Maj-Britt Bjergager; Nørum, Ulrik; Kretschmann, Andreas; Strobel, Bjarne Westergaard; Hansen, Hans Christian Bruun

    2016-04-01

    Current ecotoxicological research on particle-associated pyrethroids in freshwater systems focuses almost exclusively on sediment-exposure scenarios and sediment-dwelling macroinvertebrates. We studied how suspended particles influence acute effects of lambda-cyhalothrin and bifenthrin on the epibenthic freshwater amphipod Gammarus pulex (L.) using brief pulse exposures followed by a 144 h post exposure recovery phase. Humic acid (HA) and the clay mineral montmorillonite (MM) were used as model sorbents in environmentally realistic concentrations (5, 25 and 125 mg L(-1)). Mortality of G. pulex was recorded during the post exposure recovery phase and locomotor behavior was measured during exposure to lambda-cyhalothrin. We found that HA in concentrations ≥25 mg L(-1) adsorbed the majority of pyrethroids but only reduced mortality of G. pulex up to a factor of four compared to pyrethroid-only treatments. MM suspensions adsorbed a variable fraction of pyrethroids (10% for bifenthrin and 70% for lambda-cyhalothrin) but did not significantly change the concentration-response relationship compared to pure pyrethroid treatments. Behavioral responses and immobilisation rate of G. pulex were reduced in the presence of HA, whereas behavioral responses and immobilisation rate were increased in the presence of MM. This indicates that G. pulex was capable of sensing the bioavailable fraction of lambda-cyhalothrin. Our results imply that suspended particles reduce to only a limited extent the toxicity of pyrethroids to G. pulex and that passive uptake of pyrethroids can be significant even when pyrethroids are adsorbed to suspended particles.

  17. Early sorafenib-induced toxicity is associated with drug exposure and UGTIA9 genetic polymorphism in patients with solid tumors: a preliminary study.

    Directory of Open Access Journals (Sweden)

    Pascaline Boudou-Rouquette

    Full Text Available BACKGROUND: Identifying predictive biomarkers of drug response is of key importance to improve therapy management and drug selection in cancer therapy. To date, the influence of drug exposure and pharmacogenetic variants on sorafenib-induced toxicity remains poorly documented. The aim of this pharmacokinetic/pharmacodynamic (PK/PD study was to investigate the relationship between early toxicity and drug exposure or pharmacogenetic variants in unselected adult outpatients treated with single-agent sorafenib for advanced solid tumors. METHODS: Toxicity was recorded in 54 patients on days 15 and 30 after treatment initiation and sorafenib exposure was assessed in 51 patients. The influence of polymorphisms in CYP3A5, UGT1A9, ABCB1 and ABCG2 was examined in relation to sorafenib exposure and toxicity. Clinical characteristics, drug exposure and pharmacogenetic variants were tested univariately for association with toxicities. Candidate variables with p<0.1 were analyzed in a multivariate analysis. RESULTS: Gender was the sole parameter independently associated with sorafenib exposure (p = 0.0008. Multivariate analysis showed that increased cumulated sorafenib (AUC(cum was independently associated with any grade ≥ 3 toxicity (p = 0.037; UGT1A9 polymorphism (rs17868320 with grade ≥ 2 diarrhea (p = 0.015 and female gender with grade ≥ 2 hand-foot skin reaction (p = 0.018. Using ROC curve, the threshold AUC(cum value of 3,161 mg/L.h was associated with the highest risk to develop any grade ≥ 3 toxicity (p = 0.018. CONCLUSION: In this preliminary study, increased cumulated drug exposure and UGT1A9 polymorphism (rs17868320 identified patients at high risk for early sorafenib-induced severe toxicity. Further PK/PD studies on larger population are warranted to confirm these preliminary results.

  18. Introducing Toxics

    OpenAIRE

    David C. Bellinger

    2013-01-01

    With this inaugural issue, Toxics begins its life as a peer-reviewed, open access journal focusing on all aspects of toxic chemicals. We are interested in publishing papers that present a wide range of perspectives on toxicants and naturally occurring toxins, including exposure, biomarkers, kinetics, biological effects, fate and transport, treatment, and remediation. Toxics differs from many other journals in the absence of a page or word limit on contributions, permitting authors to present ...

  19. NTP Toxicity Study Report on the atmospheric characterization, particle size, chemical composition, and workplace exposure assessment of cellulose insulation (CELLULOSEINS).

    Science.gov (United States)

    Morgan, Daniel L

    2006-08-01

    Cellulose insulation (CI) is a type of thermal insulation produced primarily from recycled newspapers. The newspapers are shredded, milled, and treated with fire-retardant chemicals. The blowing process for installing CI generates a significant quantity of airborne material that presents a potential inhalation hazard to workers. CI was selected for study based upon the high production volume, the potential for widespread human exposure, and a lack of toxicity data; insufficient information was available to determine whether inhalation studies in laboratory animals were technically feasible or necessary. Studies were conducted to characterize the chemical and physical properties of CI aerosols, to evaluate the potential acute pulmonary toxicity of CI, and to assess occupational exposure of CI installers. Workplace exposure assessments were conducted in collaboration with the National Institute for Occupational Safety and Health (NIOSH, 2001). Chemical analyses were performed on samples of bulk CI from four major United States manufacturers. All samples of the bulk CI were found to contain primarily amorphous cellulose (60% to 65%) with a smaller crystalline component (35% to 40%). The crystalline phase was primarily native cellulose (75% to 85%) with a minor amount of cellulose nitrate (15% to 25%). Elemental analyses of acid digests of CI materials indicated that the major components (>0.1% by weight) included aluminum, boron, calcium, sodium, and sulfur. An acid-insoluble residue present in all four materials (3% to 5% of original sample weight) was found to consist primarily of aluminum silicate hydroxide (kaolinite; approximately 85%) with minor amounts (application and that the acute pulmonary toxicity is minimal. The CI exposure assessment was conducted with 10 contractors located across the United States. Air samples of total dust and respirable dust were collected for scanning electron microscopy (SEM) to characterize any fibers in the dust. Two SEM air

  20. Future research needs associated with the assessment of potential human health risks from exposure to toxic ambient air pollutants

    DEFF Research Database (Denmark)

    Möller, Lennart; Schuetzle, Dennis; Autrup, Herman

    1994-01-01

    of identification and quantification of toxics in source emissions and ambient air, atmospheric transport and chemistry, exposure level assessment, the development of improved in vitro bioassays, biomarker development, the development of more accurate epidemiological methodologies, and risk quantification......This paper presents key conclusions and future research needs from a Workshop on the Risk Assessment of Urban Air, Emissions, Exposure, Risk Identification, and Quantification, which was held in Stockholm during June 1992 by 41 participants from 13 countries. Research is recommended in the areas...... techniques. Studies are described that will be necessary to assess and reduce the level of uncertainties associated with each step of the risk assessment process. International collaborative research efforts between industry and government organizations are recommended as the most effective way to carry out...

  1. ExpoCast: Exposure Science for Prioritization and Toxicity Testing (S)

    Science.gov (United States)

    The US EPA is completing the Phase I pilot for a chemical prioritization research program, called ToxCast. Here EPA is developing methods for using computational chemistry, high-throughput screening, and toxicogenomic technologies to predict potential toxicity and prioritize limi...

  2. The pT-value as environmental policy indicator for the exposure to toxic substances

    NARCIS (Netherlands)

    Slooff W; de Zwart D

    1991-01-01

    This report contains a proposal for an indicator to measure the effectivity of the environmental policy with regard to the theme "Verspreiding" of the Directorate-General for Environmental Protection. It is recommended to use a method which indicates the toxicity of organic pollutants as

  3. Controlling silver nanoparticle exposure in algal toxicity testing - A matter of timing

    DEFF Research Database (Denmark)

    Sørensen, Sara Nørgaard; Baun, Anders

    2015-01-01

    ) in a standard algal growth inhibition test (ISO 8692:2004) for 48 h and a short-term (2 h) 14C-assimilation test. For AgNO3, similar responses were obtained in the two tests, whereas freshly prepared suspensions of citrate stabilized AgNPs were less toxic in the 2-h tests compared to the 48-h tests. The 2-h...... test was found applicable for dissolved silver, but yielded non-monotonous concentration–response relationships and poor reproducibility for freshly prepared AgNP suspensions. However, when aging AgNPs in algal medium 24 h prior to testing, clear concentration–response patterns emerged...... and reproducibility increased. Prolonged aging to 48 h increased toxicity in the 2-h tests whereas aging beyond 48 h reduced toxicity. Our results demonstrate that the outcome of algal toxicity testing of AgNPs is highly influenced not only by the test duration, but also by the time passed from the moment Ag...

  4. Toxicity bioassay and effects of sub-lethal exposure of malathion on ...

    African Journals Online (AJOL)

    Ksu-network

    2012-04-26

    Apr 26, 2012 ... glutamate pyruvic transaminase. Non-target animals including fish are greatly affected by the indiscriminate use of these pesticides. Fish appear to posses the same biochemical pathways to deal with the toxic effects of endogenous and exogenous agents as mammalian species does (Lackner, 1998).

  5. Effects of Cr III and Pb on the bioaccumulation and toxicity of Cd in tropical periphyton communities: Implications of pulsed metal exposures

    International Nuclear Information System (INIS)

    Bere, Taurai; Chia, Mathias Ahii; Tundisi, José Galizia

    2012-01-01

    Metal exposure pattern, timing, frequency, duration, recovery period, metal type and interactions, has obscured effects on periphyton communities in lotic systems. The objective of this study was to investigate the effects of intermittent exposures of Cr III and Pb on Cd toxicity and bioaccumulation in tropical periphyton communities. Natural periphyton communities were transferred to artificial stream chambers and exposed to metal mixtures at different pulse timing, duration, frequency and recovery periods. Chlorophyll a, dry mass and metal accumulation kinetics were recorded. Cr and Pb decrease the toxic effects of Cd on periphyton communities. Periphyton has high Cd, Cr and Pb accumulation capacity. Cr and Pb reduced the levels of Cd sequestrated by periphyton communities. The closer the frequency and duration of the pulse is to a continuous exposure, the greater the effects of the contaminant on periphyton growth and metal bioaccumulation. Light increased toxic and accumulative effects of metals on the periphyton community. - Highlights: ► We investigated toxicity effects of pulsed metal exposures on bioaccumulation and toxicity in periphyton. ► High frequency of short duration pulses has effects equal to long duration exposures. ► Important role of light in modulating metal toxicity on periphyton demonstrated. ► Factors other than magnitude and duration must be considered in water quality criteria. ► Accurate prediction of metal effects on biofilms requires data on effluent variability. - The study highlights the importance of pulse timing, frequency, duration, recovery period and chemical type on aquatic life.

  6. Cutaneous exposure to vesicant phosgene oxime: Acute effects on the skin and systemic toxicity

    International Nuclear Information System (INIS)

    Tewari-Singh, Neera; Goswami, Dinesh G; Kant, Rama; Croutch, Claire R; Casillas, Robert P; Orlicky, David J; Agarwal, Rajesh

    2017-01-01

    Phosgene Oxime (CX), an urticant or nettle agent categorized as a vesicant, is a potential chemical warfare and terrorist weapon. Its exposure can result in widespread and devastating effects including high mortality due to its fast penetration and ability to cause immediate severe cutaneous injury. It is one of the least studied chemical warfare agents with no effective therapy available. Thus, our goal was to examine the acute effects of CX following its cutaneous exposure in SKH-1 hairless mice to help establish a relevant injury model. Results from our study show that topical cutaneous exposure to CX vapor causes blanching of exposed skin with an erythematous ring, necrosis, edema, mild urticaria and erythema within minutes after exposure out to 8 h post-exposure. These clinical skin manifestations were accompanied with increases in skin thickness, apoptotic cell death, mast cell degranulation, myeloperoxidase activity indicating neutrophil infiltration, p53 phosphorylation and accumulation, and an increase in COX-2 and TNFα levels. Topical CX-exposure also resulted in the dilatation of the peripheral vessels with a robust increase in RBCs in vessels of the liver, spleen, kidney, lungs and heart tissues. These events could cause a drop in blood pressure leading to shock, hypoxia and death. Together, this is the first report on effects of CX cutaneous exposure, which could help design further comprehensive studies evaluating the acute and chronic skin injuries from CX topical exposure and elucidate the related mechanism of action to aid in the identification of therapeutic targets and mitigation of injury. - Highlights: • Phosgene oxime cutaneous exposure causes skin blanching, edema and urticaria. • Penetration of phosgene oxime causes dilation of vasculature in internal organs. • Mast cells could play an important role in phosgene oxime-induced skin injury. • Phosgene oxime could induce low blood pressure and hypoxia leading to mortality. • Data is

  7. Cutaneous exposure to vesicant phosgene oxime: Acute effects on the skin and systemic toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Tewari-Singh, Neera, E-mail: Neera.tewari-singh@ucdenver.edu [Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045 (United States); Goswami, Dinesh G; Kant, Rama [Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045 (United States); Croutch, Claire R; Casillas, Robert P [MRIGlobal, Kansas City, MO 64110 (United States); Orlicky, David J [Department of Pathology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045 (United States); Agarwal, Rajesh [Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045 (United States)

    2017-02-15

    Phosgene Oxime (CX), an urticant or nettle agent categorized as a vesicant, is a potential chemical warfare and terrorist weapon. Its exposure can result in widespread and devastating effects including high mortality due to its fast penetration and ability to cause immediate severe cutaneous injury. It is one of the least studied chemical warfare agents with no effective therapy available. Thus, our goal was to examine the acute effects of CX following its cutaneous exposure in SKH-1 hairless mice to help establish a relevant injury model. Results from our study show that topical cutaneous exposure to CX vapor causes blanching of exposed skin with an erythematous ring, necrosis, edema, mild urticaria and erythema within minutes after exposure out to 8 h post-exposure. These clinical skin manifestations were accompanied with increases in skin thickness, apoptotic cell death, mast cell degranulation, myeloperoxidase activity indicating neutrophil infiltration, p53 phosphorylation and accumulation, and an increase in COX-2 and TNFα levels. Topical CX-exposure also resulted in the dilatation of the peripheral vessels with a robust increase in RBCs in vessels of the liver, spleen, kidney, lungs and heart tissues. These events could cause a drop in blood pressure leading to shock, hypoxia and death. Together, this is the first report on effects of CX cutaneous exposure, which could help design further comprehensive studies evaluating the acute and chronic skin injuries from CX topical exposure and elucidate the related mechanism of action to aid in the identification of therapeutic targets and mitigation of injury. - Highlights: • Phosgene oxime cutaneous exposure causes skin blanching, edema and urticaria. • Penetration of phosgene oxime causes dilation of vasculature in internal organs. • Mast cells could play an important role in phosgene oxime-induced skin injury. • Phosgene oxime could induce low blood pressure and hypoxia leading to mortality. • Data is

  8. Use of an oiled gravel column dosing system to characterize exposure and toxicity of fish to sunken heavy oil on spawning substrates

    International Nuclear Information System (INIS)

    Martin, J.; Hodson, P.

    2010-01-01

    In August 2005, a freight train derailment near the shore of Lake Wabamun near Edmonton, Alberta resulted in the release of nearly 150,000 litres of Bunker C oil on the lakeshore. The purpose of this study was to define the toxic load of oil in sediments to better describe the exposure and toxicity of fish to sunken heavy oil on spawning substrates. Heavy Bunker C fuel contains a complex mixture of polycyclic aromatic hydrocarbons (PAH), particularly the 3-4 ringed alkylated forms that cause sublethal toxic responses in early life stages of rainbow trout (Oncorhynchus mykiss). Oil patches still persist in near-shore sediments where fish spawn. This study evaluated how the behaviour of heavy oil in water interacts with exposure and toxicity to trout embryo. Flow-through oiled gravel columns were used to determine whether the toxic constituents of heavy oil are transferred to water quickly enough to cause toxicity. Embryonic trout exposed to the outflow of these columns showed signs of sublethal toxicity and dose-dependent mortality. In addition, column output of hydrocarbons and CYP1A induction in fish were flow-dependent. The desorption kinetics of the gravel column dosing was characterized in order to evaluate the toxicity of oil on these substrates and relate it back to toxicity of oil in sediments. The time to steady-state desorption of oil constituents in water was first determined, and then the rate at which different classes of oil constituents partition into water were identified.

  9. Toxic Shock Syndrome Toxin-1-Mediated Toxicity Inhibited by Neutralizing Antibodies Late in the Course of Continual in Vivo and in Vitro Exposure

    Directory of Open Access Journals (Sweden)

    Norbert Stich

    2014-05-01

    Full Text Available Toxic shock syndrome (TSS results from the host’s overwhelming inflammatory response and cytokine storm mainly due to superantigens (SAgs. There is no effective specific therapy. Application of immunoglobulins has been shown to improve the outcome of the disease and to neutralize SAgs both in vivo and in vitro. However, in most experiments that have been performed, antiserum was either pre-incubated with SAg, or both were applied simultaneously. To mirror more closely the clinical situation, we applied a multiple dose (over five days lethal challenge in a rabbit model. Treatment with toxic shock syndrome toxin 1 (TSST-1 neutralizing antibody was fully protective, even when administered late in the course of the challenge. Kinetic studies on the effect of superantigen toxins are scarce. We performed in vitro kinetic studies by neutralizing the toxin with antibodies at well-defined time points. T-cell activation was determined by assessing T-cell proliferation (3H-thymidine incorporation, determination of IL-2 release in the cell supernatant (ELISA, and IL-2 gene activation (real-time PCR (RT-PCR. Here we show that T-cell activation occurs continuously. The application of TSST-1 neutralizing antiserum reduced IL-2 and TNFα release into the cell supernatant, even if added at later time points. Interference with the prolonged stimulation of proinflammatory cytokines is likely to be in vivo relevant, as postexposure treatment protected rabbits against the multiple dose lethal SAg challenge. Our results shed new light on the treatment of TSS by specific antibodies even at late stages of exposure.

  10. Comparison of waterborne and intraperitoneal exposure to fipronil in the Caspian white fish (Rutilus frisii on acute toxicity and histopathology

    Directory of Open Access Journals (Sweden)

    Rashid Alijani Ardeshir

    Full Text Available Fipronil is an effective insecticide widely used in agriculture with potential ecotoxicological consequences. The median lethal dose (LD50 and concentration (LC50 of fipronil in 16.3 g Caspian white fish, Rutilus frisii kutum fingerlings were determined. To determine the LD50, a total of 133 fish were assigned to 19 tanks (7 fish/tank including one control and 6 treatment groups (300, 450, 550, 650, 750, 850 mg/kg. Fish were injected intraperitoneally and monitored at 96 h. The LD50 of fipronil was 632 mg/kg suggesting it was slightly toxic to the Caspian white fish. To determine LC50, 114 fish were assigned to 19 tanks (6 fish/tank including one control and 6 treatment groups (300, 400, 500, 600, 700, 800 μg/L. The LC50 of fipronil was 572 μg/L, which was highly toxic to the fish. The degree of tissue change (DTC in vital organs from moribund fish exposed via waterborne exposure showed severe damage (DTC: 71 ± 52 for 700 μg/L in the gill, including aneurisms, extensive fusion and necrosis. The fish exposed through the intraperitoneal route seemed to have severe lesions (DTC: 66 ± 50 for 750 mg/kg in the kidney, involving hemorrhage, tubular degeneration and necrosis. The liver had no significant differences in DTC values between the two routes and showed pyknosis and sinusoid dilation. Hematoxylin and eosin staining did not show any histological alterations in the brain but nissl staining showed some alterations in distribution of purkinje cells. Generally, this study showed that the route of exposure to fipronil not only affects its acute toxicity but also determines the main target organs of toxicity and histopathological alterations in Caspian white fish. Keywords: Fipronil, Caspian white fish, Acute toxicity, Administration route

  11. Implications of exposure to dextran-coated and uncoated iron oxide nanoparticles to developmental toxicity in zebrafish

    Science.gov (United States)

    de Oliveira, Giovanna Medeiros Tavares; de Oliveira, Elisa Magno Nunes; Pereira, Talita Carneiro Brandão; Papaléo, Ricardo Meurer; Bogo, Maurício Reis

    2017-12-01

    Iron oxide nanoparticles (IONPS) have been widely investigated as a platform for a new class of multifunctional theranostic agents. They are considered biocompatible, and some formulations are already available in the market for clinical use. However, contradictory results regarding toxicity of IONPs raise a concern about the potential harm of these nanoparticles. Changes in the nanoparticle (NP) physicochemical properties or exposure media can significantly alter their behavior and, as a consequence, their toxic effects. Here, behavior and two-step RT-qPCR were employed to access the potential toxicological effects of dextran-coated IONPs (CLIO-NH2) and uncoated IONPs (UCIO) in zebrafish larvae. Animals were exposed for 7 days to NP solutions ranging from 0.1-100 μg/mL directly mixed to the system water. UCIO showed high decantation and instability in solution, altering zebrafish mortality but showing no alterations in behavior and molecular expression analysis. CLIO-NH2 exposure did not cause significant mortality or changes in hatching rate of zebrafish larvae; however, behavior and expression profiles of the group exposed to lower concentration (1 μg/mL) presented a tendency to decrease the locomotor activity and apoptotic pathway activation.

  12. Changes of lead speciation and microbial toxicity in soil treated with repeated Pb exposure in the presence of BDE209.

    Science.gov (United States)

    Zhang, Rong; Zhang, Wei; Liu, Gao; Lin, Kuangfei; Fu, Rongbing

    2016-03-01

    Lead (Pb) and decabromodiphenyl ether (BDE209) are main pollutants at electric waste (e-waste) recycling sites (EWRSs), and their joint toxicological effects have received extensive attention. Frequently, soil pollution at EWRSs usually results from the occurrence of repeated single or multiple pollution events, with continuous impacts on soil microorganisms. Therefore, a laboratory incubation study was conducted to determine Pb bioavailability and microbial toxicity in repeated Pb-polluted soil in the presence of BDE209 for the first time. We evaluated the impacts of repetitive exposure trials on chemical fractions of Pb, and the results showed that repeated single Pb pollution event resulted in an increase of carbonates fraction of Pb, which was different from one-off single Pb exposure. Moreover, one-off Pb-treated groups exhibited higher I R (reduced partition index) values on day 30 and all treatments remained the same I R level at the end of incubation period. The parameters of microbial toxicity were well reflected by soil enzymes. During the entire incubation, the dehydrogenase and urease activities were significantly inhibited by Pb (P soil enzymes were clearly observed (P < 0.05 or 0.01). Such observations would provide useful information for ecological effects of Pb and BDE209 at EWRSs.

  13. Dietary exposure to essential and potentially toxic elements for the population of Hanoi, Vietnam

    DEFF Research Database (Denmark)

    Marcussen, H.; Jensen, Bodil Hamborg; Petersen, Annette

    2013-01-01

    Knowledge of the dietary intake of essential and toxic elements in fast-developing Southeast Asian countries such as Vietnam is limited. Iron and Zn deficiency in Asia is a well-known problem and is partly due to rice constituting a major part of the diet. Dietary habits are changing...... and there is a need to build more knowledge so that authorities can give dietary recommendations. The aim of this study was to determine the total dietary intake of essential and potentially toxic elements and to assess the nutritional quality and food safety risks of the average Hanoi diet. 22 foods or food groups...... were identified and 14 samples of each food group were collected from markets and/or supermarkets in the period 2007-2009. Water spinach, water dropwort, watercress, water mimosa and pond fish are typically produced in wastewater-fed systems. Therefore, these samples were collected both at markets...

  14. Hepatic toxicity assessment of cationic liposome exposure in healthy and chronic alcohol fed mice

    DEFF Research Database (Denmark)

    Kermanizadeh, Ali; Jacobsen, Nicklas R.; Roursgaard, Martin

    2017-01-01

    or chronically alcohol fed mice. Additionally, the in vitro material-induced adverse effects (cytotoxicity, inflammation or albumin secretion) were all also minimal. The data from this study demonstrated that the intravenous injection of cationic liposomes does not cause hepatic toxicity. This investigation......, the question of potential toxicological effects needs to be addressed. In the present investigation, a cationic liposome with prospective for medical applications was constructed and thoroughly assessed for any material-induced hepatic adverse effects in vivo − in healthy and alcoholic hepatic disease models...... is important as it investigates the toxicity of a nano-sized material in a model of alcoholic hepatic disease in vitro and in vivo. This is an area of research in the field of nanotoxicology that is currently almost entirely overlooked....

  15. Concentrations, sources and human health risk of inhalation exposure to air toxics in Edmonton, Canada.

    Science.gov (United States)

    Bari, Md Aynul; Kindzierski, Warren B

    2017-04-01

    With concern about levels of air pollutants in recent years in the Capital Region of Alberta, an investigation of ambient concentrations, sources and potential human health risk of hazardous air pollutants (HAPs) or air toxics was undertaken in the City of Edmonton over a 5-year period (2009-2013). Mean concentrations of individual HAPs in ambient air including volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs) and trace metals ranged from 0.04 to 1.73 μg/m 3 , 0.01-0.54 ng/m 3 , and 0.05-3.58 ng/m 3 , respectively. Concentrations of benzene, naphthalene, benzo(a)pyrene (BaP), arsenic, manganese and nickel were far below respective annual Alberta Ambient Air Quality Objectives. Carcinogenic and non-carcinogenic risk of air toxics were also compared with risk levels recommended by regulatory agencies. Positive matrix factorization identified six air toxics sources with traffic as the dominant contributor to total HAPs (4.33 μg/m 3 , 42%), followed by background/secondary organic aerosol (SOA) (1.92 μg/m 3 , 25%), fossil fuel combustion (0.92 μg/m 3 , 11%). On high particulate air pollution event days, local traffic was identified as the major contributor to total HAPs compared to background/SOA and fossil fuel combustion. Carcinogenic risk values of traffic, background/SOA and metals industry emissions were above the USEPA acceptable level (1 × 10 -6 ), but below a tolerable risk (1 × 10 -4 ) and Alberta benchmark (1 × 10 -5 ). These findings offer useful preliminary information about current ambient air toxics levels, dominant sources and their potential risk to public health; and this information can support policy makers in the development of appropriate control strategies if required. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Potential citric acid exposure and toxicity to Hawaiian hoary bats (Lasiurus cinereus semotus) associated with Eleutherodactylus frog control.

    Science.gov (United States)

    Pitt, William C; Witmer, Gary W; Jojola, Susan M; Sin, Hans

    2014-04-01

    We examined potential exposure of Hawaiian hoary bats (Lasiurus cinereus semotus) to citric acid, a minimum risk pesticide registered for control of invasive Eleutherodactylus frog populations. Hoary bats are nocturnal insectivores that roost solitarily in foliage, federally listed as endangered, and are endemic to Hawaii. Oral ingestion during grooming of contaminated fur appears to be the principal route by which these bats might be exposed to citric acid. We made assessments of oral toxicity, citric acid consumption, retention of material on fur, and grooming using big brown bats (Eptesicus fuscus) as a surrogate species. We evaluated both ground application and aerial application of 16 % solutions of citric acid during frog control operations. Absorbent bat effigies exposed to ground and aerial operational spray applications retained means of 1.54 and 0.02 g, respectively, of dry citric acid, although retention by the effigies was much higher than bat carcasses drenched in citric acid solutions. A high dose delivered orally (2,811 mg/kg) was toxic to the big brown bats and emesis occurred in 1 bat dosed as low as the 759 mg/kg level. No effect was observed with the lower doses examined (≤ 542 mg/kg). Bats sprayed with 5 ml of 16 % (w/w) citric acid solution showed no evidence of intoxication. In field situations, it is unlikely that bats would be sprayed directly or ingest much citric acid retained by fur. Based on our observations, we believe Hawaiian hoary bats to be at very low risk from harmful exposure to a toxic dose of citric acid during frog control operations.

  17. Toxicity of thiamethoxam to Tetranychus urticae Koch and Phytoseiulus persimilis Athias-Henriot (Acari Tetranychidae, Phytoseiidae) through different routes of exposure.

    Science.gov (United States)

    Pozzebon, Alberto; Duso, Carlo; Tirello, Paola; Ortiz, Paulina Bermudez

    2011-03-01

    Knowledge of the impact of insecticides on Tetranychus urticae Koch and its predator Phytoseiulus persimilis Athias-Henriot is crucial for IPM. This study evaluates the effect of thiamethoxam on T. urticae and its predator by considering different routes of exposure (topical, residual and contaminated food exposures) and their combinations. Thiamethoxam effects on T. urticae were higher when residual and contaminated food exposures were considered. The total effect was higher than 90% where contaminated food exposure was involved. On P. persimilis, the total effect was higher in residual and contaminated prey exposures compared with topical exposure, and all combinations of routes of exposure attained a total effect higher than 90%. Thiamethoxam was found to be toxic to T. urticae and P. persimilis; however, the impact of the insecticide depended on the routes of exposure and their combinations. Lethal and sublethal effects occurred in residual and contaminated food exposures, while only sublethal effects occurred in topical exposure of predators and prey. The toxicity of thiamethoxam on prey and predator increased with the number of exposure routes involved. By limiting exposure to thiamethoxam to ingestion of contaminated food only, the impact of the pesticide was more favourable to P. persimilis than to its prey. Copyright © 2010 Society of Chemical Industry.

  18. Enhancement of parathion toxicity to quail by heat and cold exposure

    Science.gov (United States)

    Rattner, B.A.; Becker, J.M.; Nakatsugawa, T.

    1987-01-01

    Effects of ambient temperature on the acute oral toxicity of parathion were investigated in Japanese quail (Coturnix japonica) maintained at thermoneutral temperature (26.degree. C) or exposed to elevated (37.degree. C) or reduced (4.degree. C) temperatures commonly encountered by free-ranging wild birds. Based upon estimates of the median lethal dosage, there was up to a two-fold enhancement of parathion toxicity in birds chronically exposed to heat or cold. Twenty-four hours after administration of a low dosage (4 mg/kg body wt, po), there was markedly greater cholinesterase inhibition in surviving heat-exposed quail compared with those reared at 26.degree. C (e.g., brain acetylcholinesterase depression of 42% versus 12%). There were no differences in hepatic activities of parathion oxidase, paraoxonase, or paraoxon deethylase which could account for greater toxicity to chronically heat-exposed birds. In contrast, 4 mg parathion/kg wt elicited less plasma cholinesterase inhibition in cold-exposed quail compared to thermoneutral controls (e.g., birds is substantially influenced by environmental temperature.

  19. Human contamination by persistent toxic substances: the rationale to improve exposure assessment.

    Science.gov (United States)

    Porta, Miquel

    2015-10-01

    We know quite a lot about the generalized human contamination by environmental chemical agents; this statement is fully compatible with the view that most countries lack the necessary monitoring systems. We also know quite a lot about the toxic effects of environmental pollutants; this statement is fully compatible with the proposal that we need both more research and more energetic policies to decrease human contamination by such pollutants. Unsurprisingly, we know too little about the (environmental and social) causes and the etiopathogenesis (mechanisms) of the most prevalent diseases, and we will continue to miss relevant causes and mechanisms if we neglect the toxic chemicals that commonly contaminate humans, worldwide. Basic, clinical end environmental-epidemiological research on human health should more often consider integrating biomarkers of internal dose of environmental chemical pollutants. When we act in more responsible, rational, and scientific ways; when we become less dismissive towards environmental hazards; and when we thus neglect less the generalized human contamination by environmental chemical agents and their toxic effects, we will expand mechanistic biologic knowledge, and we shall as well increase the effectiveness of interventions and policies that enable the primary prevention of human diseases which cause huge amounts of economic burden and human suffering.

  20. Mortality among population with exposure to industrial air pollution containing nickel and other toxic metals.

    Science.gov (United States)

    Pasanen, Kari; Pukkala, Eero; Turunen, Anu W; Patama, Toni; Jussila, Ilkka; Makkonen, Sari; Salonen, Raimo O; Verkasalo, Pia K

    2012-05-01

    To assess disease mortality among people with exposure to metal-rich particulate air pollution. We conducted a cohort study on mortality from 1981 to 2005 among 33,573 people living near a nickel/copper smelter in Harjavalta, Finland. Nickel concentration in soil humus was selected as an indicator for long-term exposure. Relative risks--adjusted for age, socioeconomic status, and calendar period--were calculated for three exposure zones. The relative risks for diseases of the circulatory system by increasing exposure were 0.93 (95% confidence interval = 0.79 to 1.09), 1.20 (1.04 to 1.39), and 1.18 (1.00 to 1.39) among men and 1.01 (0.88 to 1.17), 1.20 (1.04 to 1.38), and 1.14 (0.97 to 1.33) among women. Exclusion of smelter workers from the cohort did not materially change the results. Long-term environmental exposure to metal-rich air pollution was associated with increased mortality from circulatory diseases.

  1. Review of refractory ceramic fiber (RCF) toxicity, epidemiology and occupational exposure.

    Science.gov (United States)

    Maxim, L Daniel; Utell, Mark J

    2018-02-01

    This literature review on refractory ceramic fibers (RCF) summarizes relevant information on manufacturing, processing, applications, occupational exposure, toxicology and epidemiology studies. Rodent toxicology studies conducted in the 1980s showed that RCF caused fibrosis, lung cancer and mesothelioma. Interpretation of these studies was difficult for various reasons (e.g. overload in chronic inhalation bioassays), but spurred the development of a comprehensive product stewardship program under EPA and later OSHA oversight. Epidemiology studies (both morbidity and mortality) were undertaken to learn more about possible health effects resulting from occupational exposure. No chronic animal bioassay studies on RCF have been conducted since the 1980s. The results of the ongoing epidemiology studies confirm that occupational exposure to RCF is associated with the development of pleural plaques and minor decrements in lung function, but no interstitial fibrosis or incremental lung cancer. Evidence supporting a finding that urinary tumors are associated with RCF exposure remains, but is weaker. One reported, but unconfirmed, mesothelioma was found in an individual with prior occupational asbestos exposure. An elevated SMR for leukemia was found, but was absent in the highly exposed group and has not been observed in studies of other mineral fibers. The industry will continue the product stewardship program including the mortality study.

  2. Co-exposure to titanium dioxide nanoparticles does not affect cadmium toxicity in radish seeds (Raphanus sativus).

    Science.gov (United States)

    Manesh, R Roshan; Grassi, G; Bergami, E; Marques-Santos, L F; Faleri, C; Liberatori, G; Corsi, I

    2018-02-01

    Recent developments on environmental fate models indicate that as nano waste, engineered nanomaterials (ENMs) could reach terrestrial ecosystems thus potentially affecting environmental and human health. Plants can be therefore exposed to ENMs but controversial data in terms of fate and toxicity are currently available. Furthermore, there is a current lack of information on complex interactions/transformations to which ENMs undergo in the natural environment as for instance interacting with existing toxic compounds. The aim of the present study was to assess the behavior and biological effects of titanium dioxide nanoparticles (n-TiO 2 ) (Aeroxide P25, Degussa Evonik) and its interaction with cadmium (CdCl 2 ) in plants using radish seeds (Raphanus sativus L. Parvus) as model species. Radish seeds were exposed to n-TiO 2 (1-1000mg/L) and CdCl 2 (1-250mg/L) alone and in combination using a seed germination and seedling growth toxicity test OECD 208. Percentage of seed germination, germination index (GI) and root elongation were calculated. Cell morphology and oxidative stress parameters as glutathione-S-transferase (GST) and catalase activities (CAT) were measured in radish seeds after 5 days of exposure. Z-Average, PdI and Z-potential of n-TiO 2 in Milli-Q water as exposure medium were also determined. DLS analysis showed small aggregates of n-TiO 2 , negative Z-potential and stable PdI in seed's exposure media. Germination percentage, GI and root length resulted affected by n-TiO 2 exposure compared to controls. In particular, n-TiO 2 at 1mg/L and 100mg/L did not affect radish seeds germination (100%) while at concentration of 10mg/L, 200mg/L, 500mg/L, and 1000mg/L a slight but not significant decrease of germination % was observed. Similarly root length and GI resulted significantly higher in seeds exposed to 10mg/L and 200mg/L compared to 1mg/L, 100mg/L, 500mg/L, 1000mg/L and control (p germination % and GI compared to control seeds and a concentration dependent

  3. Epigenetics as a mechanism linking developmental exposures to long-term toxicity

    DEFF Research Database (Denmark)

    Barouki, R; Melén, E; Herceg, Z

    2018-01-01

    A variety of experimental and epidemiological studies lend support to the Developmental Origin of Health and Disease (DOHaD) concept. Yet, the actual mechanisms accounting for mid- and long-term effects of early-life exposures remain unclear. Epigenetic alterations such as changes in DNA methylat......A variety of experimental and epidemiological studies lend support to the Developmental Origin of Health and Disease (DOHaD) concept. Yet, the actual mechanisms accounting for mid- and long-term effects of early-life exposures remain unclear. Epigenetic alterations such as changes in DNA...

  4. Sensitivity of ecological soil-screening levels for metals to exposure model parameterization and toxicity reference values.

    Science.gov (United States)

    Sample, Bradley E; Fairbrother, Anne; Kaiser, Ashley; Law, Sheryl; Adams, Bill

    2014-10-01

    Ecological soil-screening levels (Eco-SSLs) were developed by the United States Environmental Protection Agency (USEPA) for the purposes of setting conservative soil screening values that can be used to eliminate the need for further ecological assessment for specific analytes at a given site. Ecological soil-screening levels for wildlife represent a simplified dietary exposure model solved in terms of soil concentrations to produce exposure equal to a no-observed-adverse-effect toxicity reference value (TRV). Sensitivity analyses were performed for 6 avian and mammalian model species, and 16 metals/metalloids for which Eco-SSLs have been developed. The relative influence of model parameters was expressed as the absolute value of the range of variation observed in the resulting soil concentration when exposure is equal to the TRV. Rank analysis of variance was used to identify parameters with greatest influence on model output. For both birds and mammals, soil ingestion displayed the broadest overall range (variability), although TRVs consistently had the greatest influence on calculated soil concentrations; bioavailability in food was consistently the least influential parameter, although an important site-specific variable. Relative importance of parameters differed by trophic group. Soil ingestion ranked 2nd for carnivores and herbivores, but was 4th for invertivores. Different patterns were exhibited, depending on which parameter, trophic group, and analyte combination was considered. The approach for TRV selection was also examined in detail, with Cu as the representative analyte. The underlying assumption that generic body-weight-normalized TRVs can be used to derive protective levels for any species is not supported by the data. Whereas the use of site-, species-, and analyte-specific exposure parameters is recommended to reduce variation in exposure estimates (soil protection level), improvement of TRVs is more problematic. © 2014 The Authors

  5. Leg loss in Lutzomyia longipalpis (Diptera: Psychodidae) due to pyrethroid exposure: Toxic effect or defense by autotomy?

    Science.gov (United States)

    Santamaría, E; Cabrera, O L; Avendaño, J; Pardo, R H

    2016-01-01

    Phlebotomine sandflies lose their legs after exposure to pyrethroids. In some insects leg loss helps to defend them from intoxication and predation, a phenomenon known as autotomy. A field observation has shown that sandflies that have lost some legs are still able to blood-feed. The aims of the study were to determine whether leg loss in sandflies, after exposure to deltamethrin, is due to autotomy and to establish the effect of the leg loss on blood-feeding. Two experiments were carried out with Lutzomyia longipalpis: (i) Females were individually exposed to a sublethal time of deltamethrin and mortality and the number of leg loss were recorded; and (ii) Groups of females with complete legs or with 1-3 legs lost due to pyrethroid exposure were offered a blood meal and percentages of blood-fed and fully-fed females were recorded. Most females lost a median of 1 leg within 1-48 h post-exposure to deltamethrin. Mortality (after 24 h) was significantly higher for exposed females with lost legs (31.1%), compared to exposed females with complete legs (7.3%), and there were no differences in mortality between females with complete legs and the control (unexposed females). There were no differences between the three treatments in the percentages of blood-fed and fully-fed females. Leg loss in sandflies is a toxic effect of pyrethroids and there was no evidence of autotomy. The loss of up to three legs after exposure to pyrethroids does not affect blood-feeding behaviour in laboratory and probably also in wild conditions.

  6. In-Home Toxic Exposures and the Community of Individuals Who Are Developmentally Disabled

    Science.gov (United States)

    Trousdale, Kristie A.; Martin, Joyce; Abulafia, Laura; Del Bene Davis, Allison

    2010-01-01

    Chemicals are ubiquitous in the environment, and human exposure to them is inevitable. A benchmark investigation of industrial chemicals, pollutants, and pesticides in umbilical cord blood indicated that humans are born with an average of 200 pollutants already present in their bodies. The study found a total of 287 chemicals, of which, 180 are…

  7. Neurobehavioral deficits at age 7years associated with prenatal exposure to toxicants from maternal seafood diet

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Weihe, Pal; Nielsen, Flemming

    2012-01-01

    To determine the possible neurotoxic impact of prenatal exposure to polychlorinated biphenyls (PCBs), we analyzed banked cord blood from a Faroese birth cohort for PCBs. The subjects were born in 1986-1987, and 917 cohort members had completed a series of neuropsychological tests at age 7years. M...

  8. Structural, Morphological, and Functional Correlates of Corneal Endothelial Toxicity Following Corneal Exposure to Sulfur Mustard Vapor

    Science.gov (United States)

    2013-10-01

    States Depart- ment of Agriculture certificate No. 51-F-0006). All procedures were in compliance with the ARVO Statement for the Use of Animals in...exposure: pathological mechanism and poten- tial therapy. Toxicology. 2009;263:59–69. 9. Gordon MK, Desantis A, Deshmukh M, et al. Doxycycline hydrogels

  9. [Occupational toxic exposure and the pregnant woman. 2: results of a prospective study of 100 pregnancies].

    Science.gov (United States)

    Testud, F; Lambert-Chhum, R; Bellemin, B; Descotes, J

    2001-12-01

    Many women of childbearing age are occupationally exposed to chemicals and concerned with the ensuing risk when pregnant. To present the results of a prospective follow-up study of 100 pregnant women and to discuss them after a brief overview of the published data on this topic. Since January 1996 the Lyon Poison Center has been conducting a prospective follow-up of all request concerning pregnant women occupationally exposed to chemicals. A thorough evaluation of the hazards of the handled products and of the actual exposure at the workplace is done for each patient. A toxicological advice is given and the outcome of the pregnancy is followed-up. One hundred pregnant women were included between January 1996 and December 2000. Based on the nature of the handled products, two groups have been identified: the first included 73 women exposed to organic solvents and the second 27 women exposed to miscellaneous. When the exposure was considered potentially hazardous for the pregnancy, either withdrawal from the workstation (19 cases), avoidance of certain activities (9 cases) or improvement of individual protective measures (29 cases) was recommended. In 43% of the cases, the occupational exposure was not considered hazardous to the outcome of the pregnancy. No increase of adverse outcome was identified: 4 miscarriages and 96 living births were observed, with 2 major malformations and 1 minor malformation. Occupational exposure to chemicals was not found to affect adversely the outcome of these 100 pregnancies.

  10. InP/ZnS QDs exposure induces developmental toxicity in rare minnow (Gobiocypris rarus) embryos.

    Science.gov (United States)

    Chen, Yao; Yang, Yang; Ou, Fang; Liu, Li; Liu, Xiao-Hong; Wang, Zhi-Jian; Jin, Li

    2018-04-05

    We investigated the in vivo toxicity of InP/ZnS quantum dots (QDs) in Chinese rare minnow (Gobiocypris rarus) embryos. The 72 h post-fertilization (hpf) LC 50 (median lethal concentration) was 1678.007 nmol/L. Rare minnows exposed to InP/ZnS QDs exhibited decreased spontaneous movement, decreased survival and hatchability rates, and an increased malformation rate. Pericardial edema, spinal curvature, bent tails and vitelline cysts were observed. Embryonic Wnt8a and Mstn mRNA levels were significantly up-regulated after InP/ZnS QDs treatment at 48 hpf (200 nmol/L) (p InP/ZnS QDs treatments did not significantly change the Olive tail moments (p > 0.05). Thus, InP/ZnS QDs caused teratogenic effects and death during the development of Chinese rare minnow embryos, but InP/ZnS QDs did not cause significant genetic toxicity during Chinese rare minnow development. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Effect of pH and ionic strength on exposure and toxicity of encapsulated lambda-cyhalothrin to Daphnia magna.

    Science.gov (United States)

    Son, Jino; Hooven, Louisa A; Harper, Bryan; Harper, Stacey L

    2015-12-15

    Encapsulation of pesticide active ingredients in polymers has been widely employed to control the release of poorly water-soluble active ingredients. Given the high dispersibility of these encapsulated pesticides in water, they are expected to behave differently compared to their active ingredients; however, our current understanding of the fate and effects of encapsulated pesticides is still limited. In this study, we employed a central composite design (CCD) to investigate how pH and ionic strength (IS) affect the hydrodynamic diameter (HDD) and zeta potential of encapsulated λ-cyhalothrin and how those changes affect the exposure and toxicity to Daphnia magna. R(2) values greater than 0.82 and 0.84 for HDD and zeta potential, respectively, irrespective of incubation time suggest those changes could be predicted as a function of pH and IS. For HDD, the linear factor of pH and quadratic factor of pH×pH were found to be the most significant factors affecting the change of HDD at the beginning of incubation, whereas the effects of IS and IS×IS became significant as incubation time increased. For zeta potential, the linear factor of IS and quadratic factor of IS×IS were found to be the most dominant factors affecting the change of zeta potential of encapsulated λ-cyhalothrin, irrespective of incubation time. The toxicity tests with D. magna under exposure conditions in which HDD or zeta potential of encapsulated λ-cyhalothrin was maximized or minimized in the overlying water also clearly showed the worst-case exposure condition to D. magna was when the encapsulated λ-cyhalothrin is either stable or small in the overlying water. Our results show that water quality could modify the fate and toxicity of encapsulated λ-cyhalothrin in aquatic environments, suggesting understanding their aquatic interactions are critical in environmental risk assessment. Herein, we discuss the implications of our findings for risk assessment. Copyright © 2015 Elsevier B.V. All

  12. Acclimation-induced changes in toxicity and induction of metallothionein-like proteins in the fathead minnow following sublethal exposure to cobalt, silver, and zinc

    International Nuclear Information System (INIS)

    Hobson, J.F.

    1986-01-01

    Increases in tolerance and resistance to metal toxicity by aquatic organisms have been linked to elevated levels of low-molecular-weight metal-binding proteins (e.g., metallothioneins). Acclimation-induced changes in toxic response and the concentration of metallothionein-like proteins (MTP) were studied in laboratory populations of the fathead minnow, Pimephales promelas, following sublethal exposure to Co, Ag, and Zn. Following 7 and 14 days of sublethal exposure, tolerance and resistance, as measured by acute toxicity values, were altered in a dose dependent fashion. Acute toxicity values returned to control levels after 21 days of continuous exposure. Tolerance and resistance of Co- and Zn-acclimated animals were depressed after a 7-day post-acclimation period in control water. Tolerance and resistance of Ag-acclimated animals were temporarily enhanced after 7 days post-acclimation and returned to control levels after 14 days. Accumulation of Co, Ag, and Zn measured as wholebody residues appeared to be regulated in 4 of 6 exposure regimes with residues reaching stable levels after 7 to 14 days of exposure. MTP was induced by exposure to 1.8 mg Zn/L and 0.01 mg Ag/L, however, no sustained (i.e., post 21 days) tolerance or resistance were observed at these dose levels indicating that these two biological responses may not be directly related

  13. Stress exposure and the risk for the onset of alcohol use disorders and nicotine dependence in deployed military personnel: the role of prior internalizing disorders.

    Science.gov (United States)

    Trautmann, Sebastian; Schönfeld, Sabine; Behrendt, Silke; Heinrich, Anke; Höfler, Michael; Siegel, Stefan; Zimmermann, Peter; Wittchen, Hans-Ulrich

    2015-04-01

    This prospective study aimed to investigate whether prior internalizing disorders (PIDs) moderate the relationship between stress exposure (SE) and the onset of alcohol use disorders (AUDs) and nicotine dependence (ND) in deployed military personnel. 358 male soldiers were examined directly before and 12months after return from deployment using standardized interviews. Combat experiences, concerns about family disruptions, and difficult living and working environment were assessed as different aspects of SE. PID diagnoses (mood disorders (PMDs), anxiety disorders (PADs)) and substance use disorders were defined according to the DSM-IV-TR. PMDs were related to a stronger association between concerns about family disruptions and the risk of AUD onset (OR=7.7, 95% CI 1.8-32.8, p=0.006). The number of PID diagnoses (OR per diagnosis: 1.7, 95% CI 1.0-2.8, p=0.036) and PADs (OR: 2.6, 95% CI 1.1-6.3, p=0.038) were further related to a stronger association between difficult living and working environment and the risk of AUD onset. With regard to ND, PMDs were related to a weaker association between difficult living and working environment and the risk of ND onset (OR=0.4, 95% CI 0.2-0.8, p=0.013). PIDs might be related to an increased risk for the onset of AUDs but not ND following SE. This effect is probably restricted to specific constellations of PADs, PMDs, comorbid PIDs and specific aspects of SE. These critical constellations of PIDs and SE might be a promising target for future research and could contribute to the development of preventive measures to reduce the risk of AUDs following SE. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Radiation exposure of the personnel during dismantling and cutting of the primary system of the Karlsruhe Multi-purpose Research Reactor (MZFR)

    International Nuclear Information System (INIS)

    Hesse, H.; Demant, W.; Reichert, A.; Willmann, F.

    2000-10-01

    The heavy water (D 2 O) cooled and moderated pressurized water reactor MZFR with a thermal power of 200 MW will be dismantled step-by-step within the framework of sectional decommissioning licenses. The past decommissioning step (6 th sectional license) in general covered the removal of the primary systems and of all reactor support systems inside the reactor building. The measures for radiation protection during dismantling and handling of the large components of the primary system, such as the fuel element loading machine, fuel element transfer system, steam generator and pressurizer shall be pointed out. The measures taken for the reduction of the dose rate during dismantling and cutting of the components for the purpose of conditioning or unrestricted reuse at the central decontamination department (HDB) shall be described. Chemical decontamination of the primary circuit and its components, which had to be executed in order to reduce the dose rates for subsequent manual dismantling, shall be presented. The efforts undertaken for the protection of individuals in view of the difficult radiological boundary conditions (high concentrations of tritium in all systems as well as very high alpha contamination) will be explained. Moreover, dose-minimizing measures during cutting of the primary circuit and its components at HDB shall be described by the example of the cutting of a steam generator. It shall be demonstrated that cutting and dismantling of highly contaminated and activated parts with high dose rates can be executed safely in terms of both the radiation exposure of the personnel and the technical, financial and time expenditure. (orig.)

  15. Lead toxicity on hematological parameters in workers with occupational exposure to lead

    International Nuclear Information System (INIS)

    Dursun, N.; Koese, K.

    1998-01-01

    The effects of lead on hematological parameters were studied in lead exposed male workers occupied for 17.84+-4.22 years in a metal powder producing factory in Kayseri, Turkey and control male workers in same city. Blood lead and plasma zinc levels were measured by Atomic Absorption Spectrophotometry (AAS) and hematological parameters by Culture Counter S. The lead exposure workers had higher lead levels (13.81+- 9.21 mug/dl) as compared to control subjects (2.37+-0.10 mug/dl). No difference was observed in the plasma zinc levels of both groups. As indices of lead exposure, red blood cell (RBC) counts, hemoglobin (Hb), and hematocrit (Hct) values significantly decreased. Mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular haemoglobin concentration (MCHC) significantly increased except MCV. There was also an increase in MCV, but it was not significant. (author)

  16. Exposure pathways and health effects associated with chemical and radiological toxicity of natural uranium: a review.

    Science.gov (United States)

    Brugge, Doug; de Lemos, Jamie L; Oldmixon, Beth

    2005-01-01

    Natural uranium exposure derives from the mining, milling, and processing of uranium ore, as well as from ingestion of groundwater that is naturally contaminated with uranium. Ingestion and inhalation are the primary routes of entry into the body. Absorption of uranium from the lungs or digestive track is typically low but can vary depending on compound specific solubility. From the blood, two-thirds of the uranium is excreted in urine over the first 24 hours and up to 80% to 90% of uranium deposited in the bone leaves the body within 1.5 years. The primary health outcomes of concern documented with respect to uranium are renal, developmental, reproductive, diminished bone growth, and DNA damage. The reported health effects derive from experimental animal studies and human epidemiology. The Lowest Observed Adverse Effect Level (LOAEL) derived from animal studies is 50 microg/m3 for inhalation and 60 ug/kg body weight/day for ingestion. The current respiratory standard of the Occupational Safety and Health Administration (OSHA), 50 microg/m3, affords no margin of safety. Considering the safety factors for species and individual variation, the ingestion LOAEL corresponds to the daily consumption set by the World Health Organization Drinking Water Standard at 2 microg/L. Based on economic considerations, the United States Environmental Protection Agency maximum contaminant level is 30 microg/L. Further research is needed, with particular attention on the impact of uranium on indigenous populations, on routes of exposure in communities near uranium sites, on the combined exposures present at many uranium sites, on human developmental defects, and on health effects at or below established exposure standards.

  17. Antioxidant status in oral subchronic toxicity of fipronil and fluoride co-exposure in buffalo calves.

    Science.gov (United States)

    Gill, Kamalpreet Kaur; Dumka, Vinod Kumar

    2016-02-01

    The effects of fipronil and fluoride co-exposure were investigated on antioxidant status of buffalo calves. A total of 24 healthy male buffalo calves divided into 4 groups were treated for 98 consecutive days. Group I, receiving no treatment, served as the control. Animals of groups II and III were orally administered with fipronil at the dosage of 0.5 mg/kg/day and sodium fluoride (NaF) at the dosage of 6.67 mg/kg/day, respectively, for 98 days. Group IV was coadministered with fipronil and NaF at the same dosages as groups II and III. Administration of fipronil alone produced significant elevation in lipid peroxidation (LPO) and decrease in the levels of nonenzymatic antioxidant glutathione (GSH). However, it did not produce any significant effect on the activities of enzymatic antioxidants including glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD). NaF exposure led to enhanced oxidative stress as shown by significant increase in the LPO and SOD activities while GPx and CAT activities and GSH levels were significantly decreased. Co-exposure to fipronil and NaF showed additive effects on LPO, GPx activity, and GSH levels. © The Author(s) 2013.

  18. Using equilibrium passive dosing to maintain stable exposure concentrations of triclosan in a 6-week toxicity test

    DEFF Research Database (Denmark)

    Sobek, A.; Ribbenstedt, A.; Mustajärvi, L.

    2015-01-01

    toxicity tests. Yet, the European Commission’s criteria for chemicals’ risk assessments aim at protecting higher levels in the environment. To achieve protection of populations and ecosystems, reliable long-term ecotoxicologial tests are needed. In this study, we used equilibrium passive dosing to maintain...... stable exposure concentrations of triclosan (log Kow 4.8) in a 6-week multigeneration test with the benthic copepod Nitocra spinipes. The tests were performed in 10 mL vials casted with 1000 mg of silicone (DC 1-2577). Based on a previous pilot study, three triclosan concentrations were selected...... and tested (15 μg L-1; 30 μg L-1; 60 μg L-1) as well as a control (no triclosan). At test beginning, each vial contained 12 individuals consisting of 3 individuals from four different life stages. The test includes feeding with phytoplankton three times a week, which can lead to declining freely dissolved...

  19. Acute pulmonary toxicity following occupational exposure to a floor stain protector in the building industry in Switzerland.

    Science.gov (United States)

    Lazor-Blanchet, Catherine; Rusca, Sophie; Vernez, David; Berry, Raymond; Albrecht, Eric; Droz, Pierre-Olivier; Boillat, Marcel-André

    2004-05-01

    Waterproofing agents are widely applied to leather and textile garments; they are also used as floor stain protectors by professionals. Acute respiratory injury is described in three cases of young healthy adults following occupational inhalation of a new waterproofing formulation containing an acrylate fluoropolymer. Within 1 or 2 h after exposure they developed a rapidly progressive dyspnoea; two of them had hypoxaemia and flu-like reactions. All patients improved with supportive treatment in a few days. The mechanism of toxicity is still under investigation, but experimental data suggest the role of this new acrylate fluoropolymer. Tilers should be warned against spraying floor stain repellents; there is also a need to make consumers aware that the spraying of waterproofing agents in a closed environment and concomitant smoking should be avoided.

  20. The toxic exposure of flamingos to per- and Polyfluoroalkyl substances (PFAS) from firefighting foam applications in Bonaire.

    Science.gov (United States)

    de Vries, Pepijn; Slijkerman, Diana M E; Kwadijk, Christiaan J A F; Kotterman, Michiel J J; Posthuma, Leo; de Zwart, Dick; Murk, Albertinka J; Foekema, Edwin M

    2017-11-15

    In 2010 an oil terminal next to nature reservation Saliña Goto (Bonaire) caught fire. Firefighting resulted in elevated per- and polyfluoroalkyl substances (PFAS) concentrations in the salt lake. Within months flamingo abundance in Goto dropped to near complete absence. After statistical analysis, rainfall was deemed an unlikely cause for this decline. Toxicological effects on abundance of prey are likely the main cause for the flamingo absence. This reduced PFAS exposure via food and thus risk towards flamingos during the first years after the fires. Although the sediment is still polluted with persistent PFAS, flamingos returned, and started to feed on organisms with PFAS levels that exceed safety thresholds, placing the birds and other wildlife at risk. Monitoring bird populations is advised to assess potential toxic effects on birds and their offspring. This case suggests that applying persistent chemicals to reduce incident impacts may be more harmful than the incident itself. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Exposure to different toxic chemicals: a threat to environment and human health in mining sites in Tanzania

    International Nuclear Information System (INIS)

    Magduala, J.J.

    2009-01-01

    The mining activities in Tanzania have been existed since time immemorial whereby traditional mining was practiced. However until now the country is still endowed with abundant mineral resources including gold, tanzanite diamonds, iron ore, salt, gypsum, gemstones, natural gas, phosphate, coal, cobalt and nickel. The country's major gold fields are located in Geita, Musoma, Tarime, Chunya and Mpanda. During the last decade, local and foreign investors intensified their mining activities in Tanzania. This resulted in increased use of hazardous chemicals like mercury and cyanide which are harmful and toxic. In this report, the extent and impact to long term exposure of such chemicals to both natural environment and animals including human beings will be discussed. Recommendations to local and international investors and policy markers regarding the safe and sustainable use of harmful chemicals will also be discussed.(author)

  2. Proteome Profiling Reveals Potential Toxicity and Detoxification Pathways Following Exposure of BEAS-2B Cells to Engineered Titanium Dioxide Nanoparticles

    Science.gov (United States)

    Oxidative stress is known to play important roles in engineered nanomaterial induced cellular toxicity. However, the proteins and signaling pathways associated with the engineered nanomaterial mediated oxidative stress and toxicity are largely unknown. To identify these toxicity ...

  3. Use of human milk in the assessment of toxic metal exposure and essential element status in breastfeeding women and their infants in coastal Croatia.

    Science.gov (United States)

    Grzunov Letinić, Judita; Matek Sarić, Marijana; Piasek, Martina; Jurasović, Jasna; Varnai, Veda Marija; Sulimanec Grgec, Antonija; Orct, Tatjana

    2016-12-01

    Pregnant and lactating women and infants are vulnerable population groups for adverse effects of toxic metals due to their high nutritional needs and the resultant increased gastrointestinal absorption of both, essential and toxic elements. Although breastfeeding is recommended for infants worldwide, as human milk is the best source of nutrients and other required bioactive factors, it is also a pathway of maternal excretion of toxic substances including toxic metals and thus a source of infant exposure. The aim of this research was to assess health risks in breastfeeding women in the coastal area of the Republic of Croatia and their infants (N=107) due to maternal exposure to Cd and Pb via cigarette smoking, and Hg via seafood and dental amalgam fillings, and their interaction with essential elements. Biological markers of exposure were the concentrations of main toxic metals Pb, Cd and Hg in maternal blood and three types of breast milk throughout lactation stages. Biological markers of effects were the levels of essential elements Ca, Fe, Cu, Zn and Se in maternal serum and breast milk. With regard to cigarette smoking as a source of exposure to Cd and Pb, there were effects of smoking on Cd concentration in blood and correlations between the smoking index and Cd concentrations in maternal blood (ρ=0.593; Pexposure in both breastfeeding women and their infants. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. In vitro assessment of reproductive toxicity of cigarette smoke and deleterious consequences of maternal exposure to its constituents

    Directory of Open Access Journals (Sweden)

    Shao-Chin Wu

    2012-01-01

    Full Text Available Cigarette smoke is known to be a serious health risk factor and considered reproductively toxic. In the current study, we investigated whether constituents of cigarette smoke, pyrazine, 2-ethylpyridine, and 3-ethylpyridine, adversely affect reproductive functioning such as oocyte maturation and sperm capacitation. Our findings indicated that three smoke components were involved in retardation of oocyte maturation in a dose-dependent manner and the lowest-observed-adverse-effect level (LOAEL was determined to be 10-10M. However, individual smoke components administrated at the LOAEL did not attenuate oocyte maturation, demonstrating that all three toxicants were equally required for the observed growth impairment. When exposed to all three components at 10-10M during in vitro capacitation, murine sperm lost forward progression and were unable to show adequate hyperactivation, which is indicative of the incompletion of the capacitation process. Only sperm administrated with 3-ethylpyridine alone showed significant reduction in capacitation status, suggesting the chemical is the one responsible for disrupting sperm capacitation. Taken together, this is the first report that documents the effect of cigarette smoke components on oocyte maturation and sperm capacitation. The present findings demonstrate the adverse effects of smoke constituents of mammalian reproduction and the differences in sensitivity to smoke components between male and female gametes. Since both processes take place in the female reproductive system, our data provide new insights into deleterious consequences of maternal exposure to cigarette smoke.

  5. Exposure to Environmental Toxicants and Pathogenesis of Amyotrophic Lateral Sclerosis: State of the Art and Research Perspectives

    Directory of Open Access Journals (Sweden)

    Maria Rosaria Monsurrò

    2013-07-01

    Full Text Available There is a broad scientific consensus that amyotrophic lateral sclerosis (ALS, a fatal neuromuscular disease, is caused by gene-environment interactions. In fact, given that only about 10% of all ALS diagnosis has a genetic basis, gene-environmental interaction may give account for the remaining percentage of cases. However, relatively little attention has been paid to environmental and lifestyle factors that may trigger the cascade of motor neuron degeneration leading to ALS, although exposure to chemicals—including lead and pesticides—agricultural environments, smoking, intense physical activity, trauma and electromagnetic fields have been associated with an increased risk of ALS. This review provides an overview of our current knowledge of potential toxic etiologies of ALS with emphasis on the role of cyanobacteria, heavy metals and pesticides as potential risk factors for developing ALS. We will summarize the most recent evidence from epidemiological studies and experimental findings from animal and cellular models, revealing that potential causal links between environmental toxicants and ALS pathogenesis have not been fully ascertained, thus justifying the need for further research.

  6. Short - Term Exposure To Visible And Ultraviolet Light Modulates Dacarbazine Toxicity To Human Blood Cells In Vitro

    International Nuclear Information System (INIS)

    Kopjar, N.; Zunec, S.; Lucic Vrdoljak, A.; Zeljezic, D.; Mladinic, M.

    2015-01-01

    Dacarbazine (DTIC), i.e. 5-(3,3-dimethyltriazeno)imidazol-4-carboxamide, is an alkylating cytostatic used in the treatment of various types of human cancer. It is prone to photodegradation, the products of which cause adverse effects in treated patients. In the present study, we evaluated the relationships between photo genotoxicity, cytotoxicity, lipid peroxidation and AChE activity in in vitro DTIC - treated human blood after illumination with visible and ultraviolet light for 30 and 60 minutes. AChE activity was measured in erythrocytes. The extent of lipid peroxidation was measured in plasma. Cell death and morphological changes in the nuclei were studied in isolated peripheral blood lymphocytes using the fluorescent dye exclusion method. Primary DNA damage in lymphocytes was studied by alkaline comet assay immediately after treatment and 60 minutes later. The obtained results suggest that short-term exposure to UV and visible light modulated DTIC toxicity. Most of the effects were dose-dependent. We assume that photodegradation products, together with the parent compound, were responsible for increased LPO in plasma, along with cytotoxicity and infliction of primary DNA damage in lymphocytes. Erythrocyte AChE activity, on the other hand, was strongly impaired by the parent drug. Our findings suggest the need for a simultaneous evaluation of cyto-/genotoxicity and biochemical markers, as such an approach would provide much better insight into the mechanisms underlying drug toxicity in general. (author).

  7. Pyrrolizidine Alkaloid-Protein Adducts: Potential Non-invasive Biomarkers of Pyrrolizidine Alkaloid-Induced Liver Toxicity and Exposure.

    Science.gov (United States)

    Xia, Qingsu; Zhao, Yuewei; Lin, Ge; Beland, Frederick A; Cai, Lining; Fu, Peter P

    2016-08-15

    Pyrrolizidine alkaloids (PAs) are phytochemicals present in hundreds of plant species from different families widely distributed in many geographical regions around the world. PA-containing plants are probably the most common type of poisonous plants affecting livestock, wildlife, and humans. There have been many large-scale human poisonings caused by the consumption of food contaminated with toxic PAs. PAs require metabolic activation to generate pyrrolic metabolites to exert their toxicity. In this study, we developed a novel method to quantify pyrrole-protein adducts present in the blood. This method involves the use of AgNO3 in acidic ethanol to cleave the thiol linkage of pyrrole-protein (DHP-protein) adducts, and the resulting 7,9-di-C2H5O-DHP is quantified by HPLC-ES-MS/MS multiple reaction monitoring analysis in the presence of a known quantity of isotopically labeled 7,9-di-C2D5O-DHP internal standard. Using this method, we determined that diester-type PAs administered to rats produced higher levels of DHP-protein adducts than other types of PAs. The results suggest that DHP-protein adducts can potentially serve as minimally invasive biomarkers of PA exposure.

  8. St. John's wort significantly increased the systemic exposure and toxicity of methotrexate in rats

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Shih-Ying [Graduate Institute of Pharmaceutical Chemistry, China Medical University, Taichung, Taiwan (China); Juang, Shin-Hun [Graduate Institute of Pharmaceutical Chemistry, China Medical University, Taichung, Taiwan (China); Department of Medical Research, China Medical University Hospital, Taichung, Taiwan (China); Tsai, Shang-Yuan; Chao, Pei-Dawn Lee [School of Pharmacy, China Medical University, Taichung, Taiwan (China); Hou, Yu-Chi, E-mail: hou5133@gmail.com [School of Pharmacy, China Medical University, Taichung, Taiwan (China); Department of Medical Research, China Medical University Hospital, Taichung, Taiwan (China)

    2012-08-15

    St. John's wort (SJW, Hypericum perforatum) is one of the popular nutraceuticals for treating depression. Methotrexate (MTX) is an immunosuppressant with narrow therapeutic window. This study investigated the effect of SJW on MTX pharmacokinetics in rats. Rats were orally given MTX alone and coadministered with 300 and 150 mg/kg of SJW, and 25 mg/kg of diclofenac, respectively. Blood was withdrawn at specific time points and serum MTX concentrations were assayed by a specific monoclonal fluorescence polarization immunoassay method. The results showed that 300 mg/kg of SJW significantly increased the AUC{sub 0−t} and C{sub max} of MTX by 163% and 60%, respectively, and 150 mg/kg of SJW significantly increased the AUC{sub 0−t} of MTX by 55%. In addition, diclofenac enhanced the C{sub max} of MTX by 110%. The mortality of rats treated with SJW was higher than that of controls. In conclusion, coadministration of SJW significantly increased the systemic exposure and toxicity of MTX. The combined use of MTX with SJW would need to be with caution. -- Highlights: ► St. John's wort significantly increased the AUC{sub 0−t} and C{sub max} of methotrexate. ► Coadministration of St. John's wort increased the exposure and toxicity of methotrexate. ► The combined use of methotrexate with St. John's wort will need to be with caution.

  9. Toxicity and trophic transfer of P25 TiO2 NPs from Dunaliella salina to Artemia salina: Effect of dietary and waterborne exposure.

    Science.gov (United States)

    Bhuvaneshwari, M; Thiagarajan, Vignesh; Nemade, Prateek; Chandrasekaran, N; Mukherjee, Amitava

    2018-01-01

    The recent increase in nanoparticle (P25 TiO 2 NPs) usage has led to concerns regarding their potential implications on environment and human health. The food chain is the central pathway for nanoparticle transfer from lower to high trophic level organisms. The current study relies on the investigation of toxicity and trophic transfer potential of TiO 2 NPs from marine algae Dunaliella salina to marine crustacean Artemia salina. Toxicity was measured in two different modes of exposure such as waterborne (exposure of TiO 2 NPs to Artemia) and dietary exposure (NP-accumulated algal cells are used to feed the Artemia). The toxicity and accumulation of TiO 2 NPs in marine algae D. salina were also studied. Artemia was found to be more sensitive to TiO 2 NPs (48h LC 50 of 4.21mgL -1 ) as compared to marine algae, D. salina (48h LC 50 of 11.35mgL -1 ). The toxicity, uptake, and accumulation of TiO 2 NPs were observed to be more in waterborne exposure as compared to dietary exposure. Waterborne exposure seemed to cause higher ROS production and antioxidant enzyme (SOD and CAT) activity as compared to dietary exposure of TiO 2 NPs in Artemia. There were no observed biomagnification (BMF) and trophic transfer from algae to Artemia through dietary exposure. Histopathological studies confirmed the morphological and internal damages in Artemia. This study reiterates the possible effects of the different modes of exposure on trophic transfer potential of TiO 2 NPs and eventually the consequences on aquatic environment. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Emissions from Electronic Cigarettes: Assessing Vapers' Intake of Toxic Compounds, Secondhand Exposures, and the Associated Health Impacts.

    Science.gov (United States)

    Logue, Jennifer M; Sleiman, Mohamad; Montesinos, V Nahuel; Russell, Marion L; Litter, Marta I; Benowitz, Neal L; Gundel, Lara A; Destaillats, Hugo

    2017-08-15

    E-cigarettes likely represent a lower risk to health than traditional combustion cigarettes, but they are not innocuous. Recently reported emission rates of potentially harmful compounds were used to assess intake and predict health impacts for vapers and bystanders exposed passively. Vapers' toxicant intake was calculated for scenarios in which different e-liquids were used with various vaporizers, battery power settings and vaping regimes. For a high rate of 250 puff day -1 using a typical vaping regime and popular tank devices with battery voltages from 3.8 to 4.8 V, users were predicted to inhale formaldehyde (up to 49 mg day -1 ), acrolein (up to 10 mg day -1 ) and diacetyl (up to 0.5 mg day -1 ), at levels that exceeded U.S. occupational limits. Formaldehyde intake from 100 daily puffs was higher than the amount inhaled by a smoker consuming 10 conventional cigarettes per day. Secondhand exposures were predicted for two typical indoor scenarios: a home and a bar. Contributions from vaping to air pollutant concentrations in the home did not exceed the California OEHHA 8-h reference exposure levels (RELs), except when a high emitting device was used at 4.8 V. In that extreme scenario, the contributions from vaping amounted to as much as 12 μg m -3 formaldehyde and 2.6 μg m -3 acrolein. Pollutant concentrations in bars were modeled using indoor volumes, air exchange rates and the number of hourly users reported in the literature for U.S. bars in which smoking was allowed. Predicted contributions to indoor air levels were higher than those in the residential scenario. Formaldehyde (on average 135 μg m -3 ) and acrolein (28 μg m -3 ) exceeded the acute 1-h exposure REL for the highest emitting vaporizer/voltage combination. Predictions for these compounds also exceeded the 8-h REL in several bars when less intense vaping conditions were considered. Benzene concentrations in a few bars approached the 8-h REL, and diacetyl levels were close to the lower limit

  11. Toxic Elements

    DEFF Research Database (Denmark)

    Hajeb, Parvaneh; Shakibazadeh, Shahram; Sloth, Jens Jørgen

    2016-01-01

    Food is considered the main source of toxic element (arsenic, cadmium, lead, and mercury) exposure to humans, and they can cause major public health effects. In this chapter, we discuss the most important sources for toxic element in food and the foodstuffs which are significant contributors to h...

  12. Antimony Toxicity

    OpenAIRE

    Sundar, Shyam; Chakravarty, Jaya

    2010-01-01

    Antimony toxicity occurs either due to occupational exposure or during therapy. Occupational exposure may cause respiratory irritation, pneumoconiosis, antimony spots on the skin and gastrointestinal symptoms. In addition antimony trioxide is possibly carcinogenic to humans. Improvements in working conditions have remarkably decreased the incidence of antimony toxicity in the workplace. As a therapeutic, antimony has been mostly used for the treatment of leishmaniasis and schistosomiasis. The...

  13. Toenail as Non-invasive Biomarker in Metal Toxicity Measurement of Welding Fumes Exposure - A Review

    Science.gov (United States)

    Bakri, S. F. Z.; Hariri, A.; Ma'arop, N. F.; Hussin, N. S. A. W.

    2017-01-01

    Workers are exposed to a variety of heavy metal pollutants that are released into the environment as a consequence of workplace activities. This chemical pollutants are incorporated into the human by varies of routes entry and can then be stored and distributed in different tissues, consequently have a potential to lead an adverse health effects and/or diseases. As to minimize the impact, a control measures should be taken to avoid these effects and human biological marker is a very effective tool in the assessment of occupational exposure and potential related risk as the results is normally accurate and reproducible. Toenail is the ideal matrix for most common heavy metals due to its reliability and practicality compared to other biological samples as well as it is a non-invasive and this appears as a huge advantage of toenail as a biomarker. This paper reviews studies that measure the heavy metals concentration in toenail as non-invasive matrix which later may adapt in the investigation of metal fume emitted from welding process. The development of new methodology and modern analytical techniques has allowed the use of toenail as non-invasive approach. The presence of a heavy metal in this matrix reflects an exposure but the correlations between heavy metal levels in the toenail must be established to ensure that these levels are related to the total body burden. These findings suggest that further studies on interactions of these heavy metals in metal fumes utilizing toenail biomarker endpoints are highly warranted especially among welders.

  14. Evaluation of potential toxicity from co-exposure to three CNS depressants (toluene, ethylbenzene, and xylene) under resting and working conditions using PBPK modeling.

    Science.gov (United States)

    Dennison, James E; Bigelow, Philip L; Mumtaz, Moiz M; Andersen, Melvin E; Dobrev, Ivan D; Yang, Raymond S H

    2005-03-01

    Under OSHA and American Conference of Governmental Industrial Hygienists (ACGIH) guidelines, the mixture formula (unity calculation) provides a method for evaluating exposures to mixtures of chemicals that cause similar toxicities. According to the formula, if exposures are reduced in proportion to the number of chemicals and their respective exposure limits, the overall exposure is acceptable. This approach assumes that responses are additive, which is not the case when pharmacokinetic interactions occur. To determine the validity of the additivity assumption, we performed unity calculations for a variety of exposures to toluene, ethylbenzene, and/or xylene using the concentration of each chemical in blood in the calculation instead of the inhaled concentration. The blood concentrations were predicted using a validated physiologically based pharmacokinetic (PBPK) model to allow exploration of a variety of exposure scenarios. In addition, the Occupational Safety and Health Administration and ACGIH occupational exposure limits were largely based on studies of humans or animals that were resting during exposure. The PBPK model was also used to determine the increased concentration of chemicals in the blood when employees were exercising or performing manual work. At rest, a modest overexposure occurs due to pharmacokinetic interactions when exposure is equal to levels where a unity calculation is 1.0 based on threshold limit values (TLVs). Under work load, however, internal exposure was 87%higher than provided by the TLVs. When exposures were controlled by a unity calculation based on permissible exposure limits (PELs), internal exposure was 2.9 and 4.6 times the exposures at the TLVs at rest and workload, respectively. If exposure was equal to PELs outright, internal exposure was 12.5 and 16 times the exposure at the TLVs at rest and workload, respectively. These analyses indicate the importance of (1) selecting appropriate exposure limits, (2) performing unity

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

    Directory of Open Access Journals (Sweden)

    2011-05-01

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

  16. Gestational exposure to BDE-99 produces toxicity through upregulation of CYP isoforms and ROS production in the fetal rat liver.

    Science.gov (United States)

    Blanco, Jordi; Mulero, Miquel; Domingo, José L; Sánchez, Domènec J

    2012-05-01

    On gestation day (GD) 6 to GD 19, pregnant Sprague Dawley rats were orally exposed to 0, 0.5, 1, and 2 mg/kg/day to one of the most prevalent polybrominated diphenyl ethers congeners found in humans, 2,2',4,4',5-pentaBDE (BDE-99). All dams were euthanized on GD 20, and live fetuses were evaluated for sex, body weight, and external, internal, and skeletal malformations and developmental variations. The liver from one fetus of each litter was excised for the evaluation of oxidative stress markers and the messenger RNA expression of multiple cytochrome P450 (CYP) isoforms. Exposure to BDE-99 during the gestational period produced delayed ossification, slight hypertrophy of the heart, and enlargement of the liver in fetuses. A transplacental effect of BDE-99, evidenced by the activation of nuclear hormones receptors that induce the upregulation of CYP1A1, CYP1A2, CYP2B1, and CYP3A2 isoforms, was also found in fetal liver. These isoforms are correlated with the activity level of the enzyme catalase and the levels of thiobarbituric acid reactive substances. However, teratogenic effects from BDE-99 exposure were not observed. Clear signs of embryo/fetal toxicity, due to a possible hormonal disruption, were evidenced by a large increase in the CYP system and the production of reactive oxygen species in fetal liver.

  17. Nickel toxicity to benthic organisms: The role of dissolved organic carbon, suspended solids, and route of exposure.

    Science.gov (United States)

    Custer, Kevin W; Hammerschmidt, Chad R; Burton, G Allen

    2016-01-01

    Nickel bioavailability is reduced in the presence of dissolved organic carbon (DOC), suspended solids (TSS), and other complexing ligands; however, no studies have examined the relative importance of Ni exposure through different compartments (water, sediment, food). Hyalella azteca and Lymnaea stagnalis were exposed to Ni-amended water, sediment, and food, either separately or in combination. Both organisms experienced survival and growth effects in several Ni compartment tests. The DOC amendments attenuated L. stagnalis Ni effects (survival, growth, and (62)Ni bioaccumulation), and presence of TSS exposures demonstrated both protective and synergistic effects on H. azteca and L. stagnalis. (62)Ni trophic transfer from food to H. azteca and L. stagnalis was negligible; however, bioaccumulating (62)Ni was attributed to (62)Ni-water ((62)Ni flux from food), (62)Ni-TSS, and (62)Ni-food. Overall, H. azteca and L. stagnalis Ni compartment toxicity increased in the following order: Ni-water > Ni-sediment > Ni-all (water, sediment, food) > Ni-food. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Critical comparison of intravenous injection of TiO2 nanoparticles with waterborne and dietary exposures concludes minimal environmentally-relevant toxicity in juvenile rainbow trout Oncorhynchus mykiss

    International Nuclear Information System (INIS)

    Boyle, David; Al-Bairuty, Genan A.; Henry, Theodore B.; Handy, Richard D.

    2013-01-01

    A critical comparison of studies that have investigated tissue accumulation and toxicity of TiO 2 -NPs in fish is necessary to resolve inconsistencies. The present study used identical TiO 2 -NPs, toxicological endpoints, and fish (juvenile rainbow trout Oncorhynchus mykiss) as previous studies that investigated waterborne and dietary toxicity of TiO 2 -NPs, and conducted a critical comparison of results after intravenous caudal-vein injection of 50 μg of TiO 2 -NPs and bulk TiO 2 . Injected TiO 2 -NPs accumulated only in kidney (94% of measured Ti) and to a lesser extent in spleen; and injected bulk TiO 2 was found only in kidney. No toxicity of TiO 2 was observed in kidney, spleen, or other tissues. Critical comparison of these data with previous studies indicates that dietary and waterborne exposures to TiO 2 -NPs do not lead to Ti accumulation in internal tissues, and previous reports of minor toxicity are inconsistent or attributable to respiratory distress resulting from gill occlusion during waterborne exposure. -- Highlights: •Critical comparison of TiO 2 -NP toxicity studies in rainbow trout. •No evidence of TiO 2 -NP absorption in internal tissues. •Conclude minimal environmentally relevant toxicity of TiO 2 -NPs in rainbow trout. -- Critical evaluation of directly comparable investigations of TiO 2 -NP toxicity by waterborne, dietary, and intravenous injection exposures conclude minimal toxicity in juvenile rainbow trout

  19. Availability of treatment resources for the management of acute toxic exposures and poisonings in emergency departments among various types of hospitals in Palestine: a cross-sectional study

    OpenAIRE

    Zyoud, Sa’ed H; Al-Jabi, Samah W; Bali, Yara I; Al-Sayed, Afnan M; Sweileh, Waleed M; Awang, Rahmat

    2014-01-01

    Background Poisoning exposures continue to be a significant cause of morbidity and mortality worldwide. The lack of facilities, treatment resources, and antidotes in hospitals may affect the treatments provided and outcomes. This study aimed to determine the availability of gastrointestinal (GI) decontamination, stabilisation, elimination enhancement resources, and antidotes for the management of acute toxic exposures and poisonings in emergency departments (EDs) among various types of govern...

  20. Developmental toxicity in white leghorn chickens following in ovo exposure to perfluorooctane sulfonate (PFOS)

    Science.gov (United States)

    Peden-Adams, M. M.; Stuckey, Joyce E.; Gaworecki, K.M.; Berger-Ritchie, J.; Bryant, K.; Jodice, P.G.; Scott, T.R.; Ferrario, J.B.; Guan, B.; Vigo, C.; Boone, J.S.; McGuinn, W.D.; DeWitt, J.C.; Keil, D.E.

    2009-01-01

    Studies show that perfluorinated compounds cause various toxicological effects; nevertheless, effects on immune function and developmental endpoints have not been addressed at length. This study examined the effects of perfluorooctane sulfonate (PFOS) in white leghorn hatchlings on various developmental, immunological, and clinical health parameters. In addition, serum PFOS concentrations were determined by LC/MS/MS. Embryonic day (ED) 0 eggs were injected with either safflower oil/10% DMSO (control, 0 mg/kg egg wt) or PFOS in safflower oil/10% DMSO at 1, 2.5, or 5 mg/kg egg wt, and the chicks were grown to post-hatch day (PHD) 14. Treatment with PFOS did not affect hatch rate. Following in ovo exposure chicks exhibited increases in spleen mass at all treatment levels, in liver mass at 2.5 and 5 mg/kg egg wt, and in body length (crown-rump length) at the 5 mg/kg treatment. Right wings were shorter in all treatments compared to control. Increases in the frequency of brain asymmetry were evident in all treatment groups. SRBC-specific immunoglobulin (IgM and IgY combined) titers were decreased significantly at all treatment levels, while plasma lysozyme activity was increased at all treatment levels. The PHA skin test response decreased in relation to increasing PFOS dose. Serum concentrations where significant immunological, morphological, and neurological effects were observed at the lowest dose (1 mg/kg egg wt) averaged 154 ng PFOS/g serum. These concentrations fall within environmental ranges reported in blood samples from wild caught avian species; thereby, verifying that the environmental egg concentrations used for the injections do indeed relate to serum levels in hatchlings that are also environmentally relevant. These data indicate that immune alterations and brain asymmetry can occur in birds following in ovo exposure to environmentally relevant concentrations of PFOS and demonstrates the need for further research on the developmental effects of

  1. Cadmium toxicity studies under long term-low level exposure (LLE) conditions. I

    International Nuclear Information System (INIS)

    Sabbioni, E.; Marafante, E.; Amantini, L.; Ubertalli, L.; Pietra, R.

    1978-01-01

    A long term-low level exposure (LLE) experiment was conducted on rats to determine the metabolic patterns for realistic dietary levels of cadmium. Male rats fed with 61 ppb of cadmium ad libitum, 50 labelled with 109 Cd radiotracer as cadmium chloride via drinking mineral water and 11 unlabelled via food for 2 years. The diet was characterized in its metal content by neutron activation analysis to obtain the total dietary intake of different elements. The kidney was found to be the tissue with the major concentration of cadmium which accumulated continuously during the experiment. The variation of the accumulation pattern of Cd concentration in the liver and intestine indicated an initial rapid increase of Cd during the first 100 days. After this period an apparent equilibrium was attained in both these tissues until the end of the study. The intracellular distribution of cadmium in kidneys, liver, intestine and pancreas were similar, the cytosol fractions containing about 80% of the cellular cadmium. Dialysis experiments indicated that significant amounts of cadmium were able to be associated with cellular organelles, the mitochondria representing the most important organelle capable of binding cadmium. The cytoplasmatic Cd-profiles obtained at various stages of the experiment showed that the metal was only bound to a low-molecular-weight component, cadmium-binding protein (CdBP), which represents the specific cellular-binding component for cadmium under the long term-low level exposure (LLE) conditions. No significant variations in the concentrations of the elements in different organs were observed in animals supplemented with 109 Cd in respect to 109 Cd untreated controls. (Auth.)

  2. N-Acetyl Cysteine does not prevent liver toxicity from chronic low dose plus sub-acute high dose paracetamol exposure in young or old mice

    Science.gov (United States)

    Kane, Alice-Elizabeth; Huizer-Pajkos, Aniko; Mach, John; McKenzie, Catriona; Mitchell, Sarah-Jayne; de Cabo, Rafael; Jones, Brett; Cogger, Victoria; Le Couteur, David G; Hilmer, Sarah-Nicole

    2016-01-01

    Paracetamol is an analgesic commonly used by people of all ages, which is well documented to cause severe hepatotoxicity with acute over-exposures. The risk of hepatotoxicity from non-acute paracetamol exposures is less extensively studied, and this is the exposure most common in older adults. Evidence on the effectiveness of N-acetyl cysteine (NAC) for non-acute paracetamol exposures, in any age group, is lacking. This study aimed to examine the effect of long-term exposure to therapeutic doses of paracetamol and sub-acute paracetamol over-exposure, in young and old mice, and to investigate whether NAC was effective at preventing paracetamol hepatotoxicity induced by these exposures. Young and old male C57BL/6 mice were fed a paracetamol-containing (1.33g/kg food) or control diet for 6 weeks. Mice were then dosed orally 8 times over 3 days with additional paracetamol (250mg/kg) or saline, followed by either one or two doses of oral NAC (1200mg/kg) or saline. Chronic low-dose paracetamol exposure did not cause hepatotoxicity in young or old mice, measured by serum alanine aminotransferase (ALT) elevation, and confirmed by histology and a DNA fragmentation assay. Sub-acute paracetamol exposure caused significant hepatotoxicity in young and old mice, measured by biochemistry (ALT) and histology. Neither a single nor double dose of NAC protected against this toxicity from sub-acute paracetamol in young or old mice. This finding has important clinical implications for treating toxicity due to different paracetamol exposure types in patients of all ages, and implies a need to develop new treatments for sub-acute paracetamol toxicity. PMID:26821200

  3. Exposure of sea bream (Sparus aurata) to toxic concentrations of benzo[a]pyrene: possible human health effect.

    Science.gov (United States)

    Zena, R; Speciale, A; Calabrò, C; Calò, M; Palombieri, D; Saija, A; Cimino, F; Trombetta, D; Lo Cascio, P

    2015-12-01

    Polycyclic aromatic hydrocarbons (PAHs) can accumulate in the food chain, due to their lipophilic properties. Fish can accumulate contaminants including PAHs and frequent consumption of such contaminated fish can pose risk to human health. The aim of this study was to clarify if acute exposure of sea bream (Sparus aurata, a fish species of great economic importance in the Atlantic and Mediterranean areas) to a PAH, benzo[a]pyrene (B[a]P), at a dose that can induce CYP1A and pathological changes in fish gills, liver and muscle, can induce accumulation in muscle. We investigated the cytotoxic effects (as changes in cell viability, DNA laddering and glutathione content) of in vitro exposure of human peripheral blood mononuclear cells (PBMCs) to organic extracts obtained from muscle of sea breams previously exposed via water to B[a]P (2mg/l, for 12, 24 and 72 h). At this level of exposure, B[a]P caused morphological changes, inflammatory response and CYP1A induction not only in sea bream gills and liver but also in muscle; furthermore, in fish muscle we observed a substantial B[a]P accumulation, which may be associated with the increased CYP1A activity in liver and especially in muscle. However, when PBMCs were exposed to organic extracts obtained from sea bream muscle contaminated with B[a]P, a toxic, although modest effect was revealed, consisting in a significant decrease in cell glutathione levels without alterations in cell viability and DNA laddering. This suggests that consumption of sea breams from B[a]P contaminated waters might represent a risk for human health. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Reference manual for toxicity and exposure assessment and risk characterization. CERCLA Baseline Risk Assessment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, 1980) (CERCLA or Superfund) was enacted to provide a program for identifying and responding to releases of hazardous substances into the environment. The Superfund Amendments and Reauthorization Act (SARA, 1986) was enacted to strengthen CERCLA by requiring that site clean-ups be permanent, and that they use treatments that significantly reduce the volume, toxicity, or mobility of hazardous pollutants. The National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (USEPA, 1985; USEPA, 1990) implements the CERCLA statute, presenting a process for (1) identifying and prioritizing sites requiring remediation and (2) assessing the extent of remedial action required at each site. The process includes performing two studies: a Remedial Investigation (RI) to evaluate the nature, extent, and expected consequences of site contamination, and a Feasibility Study (FS) to select an appropriate remedial alternative adequate to reduce such risks to acceptable levels. An integral part of the RI is the evaluation of human health risks posed by hazardous substance releases. This risk evaluation serves a number of purposes within the overall context of the RI/FS process, the most essential of which is to provide an understanding of ``baseline`` risks posed by a given site. Baseline risks are those risks that would exist if no remediation or institutional controls are applied at a site. This document was written to (1) guide risk assessors through the process of interpreting EPA BRA policy and (2) help risk assessors to discuss EPA policy with regulators, decision makers, and stakeholders as it relates to conditions at a particular DOE site.

  5. Reference manual for toxicity and exposure assessment and risk characterization. CERCLA Baseline Risk Assessment

    International Nuclear Information System (INIS)

    1995-03-01

    The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, 1980) (CERCLA or Superfund) was enacted to provide a program for identifying and responding to releases of hazardous substances into the environment. The Superfund Amendments and Reauthorization Act (SARA, 1986) was enacted to strengthen CERCLA by requiring that site clean-ups be permanent, and that they use treatments that significantly reduce the volume, toxicity, or mobility of hazardous pollutants. The National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (USEPA, 1985; USEPA, 1990) implements the CERCLA statute, presenting a process for (1) identifying and prioritizing sites requiring remediation and (2) assessing the extent of remedial action required at each site. The process includes performing two studies: a Remedial Investigation (RI) to evaluate the nature, extent, and expected consequences of site contamination, and a Feasibility Study (FS) to select an appropriate remedial alternative adequate to reduce such risks to acceptable levels. An integral part of the RI is the evaluation of human health risks posed by hazardous substance releases. This risk evaluation serves a number of purposes within the overall context of the RI/FS process, the most essential of which is to provide an understanding of ''baseline'' risks posed by a given site. Baseline risks are those risks that would exist if no remediation or institutional controls are applied at a site. This document was written to (1) guide risk assessors through the process of interpreting EPA BRA policy and (2) help risk assessors to discuss EPA policy with regulators, decision makers, and stakeholders as it relates to conditions at a particular DOE site

  6. Prediction of paraquat exposure and toxicity in clinically ill poisoned patients: a model based approach.

    Science.gov (United States)

    Wunnapuk, Klintean; Mohammed, Fahim; Gawarammana, Indika; Liu, Xin; Verbeeck, Roger K; Buckley, Nicholas A; Roberts, Michael S; Musuamba, Flora T

    2014-10-01

    Paraquat poisoning is a medical problem in many parts of Asia and the Pacific. The mortality rate is extremely high as there is no effective treatment. We analyzed data collected during an ongoing cohort study on self-poisoning and from a randomized controlled trial assessing the efficacy of immunosuppressive therapy in hospitalized paraquat-intoxicated patients. The aim of this analysis was to characterize the toxicokinetics and toxicodynamics of paraquat in this population. A non-linear mixed effects approach was used to perform a toxicokinetic/toxicodynamic population analysis in a cohort of 78 patients. The paraquat plasma concentrations were best fitted by a two compartment toxicokinetic structural model with first order absorption and first order elimination. Changes in renal function were used for the assessment of paraquat toxicodynamics. The estimates of toxicokinetic parameters for the apparent clearance, the apparent volume of distribution and elimination half-life were 1.17 l h(-1) , 2.4 l kg(-1) and 87 h, respectively. Renal function, namely creatinine clearance, was the most significant covariate to explain between patient variability in paraquat clearance.This model suggested that a reduction in paraquat clearance occurred within 24 to 48 h after poison ingestion, and afterwards the clearance was constant over time. The model estimated that a paraquat concentration of 429 μg l(-1) caused 50% of maximum renal toxicity. The immunosuppressive therapy tested during this study was associated with only 8% improvement of renal function. The developed models may be useful as prognostic tools to predict patient outcome based on patient characteristics on admission and to assess drug effectiveness during antidote drug development. © 2014 The British Pharmacological Society.

  7. Exposure to Enriched Environment Decreases Neurobehavioral Deficits Induced by Neonatal Glutamate Toxicity

    Directory of Open Access Journals (Sweden)

    Peter Kiss

    2013-09-01

    Full Text Available Environmental enrichment is a popular strategy to enhance motor and cognitive performance and to counteract the effects of various harmful stimuli. The protective effects of enriched environment have been shown in traumatic, ischemic and toxic nervous system lesions. Monosodium glutamate (MSG is a commonly used taste enhancer causing excitotoxic effects when given in newborn animals. We have previously demonstrated that MSG leads to a delay in neurobehavioral development, as shown by the delayed appearance of neurological reflexes and maturation of motor coordination. In the present study we aimed at investigating whether environmental enrichment is able to decrease the neurobehavioral delay caused by neonatal MSG treatment. Newborn pups were treated with MSG subcutaneously on postnatal days 1, 5 and 9. For environmental enrichment, we placed rats in larger cages, supplemented with different toys that were altered daily. Normal control and enriched control rats received saline treatment only. Physical parameters such as weight, day of eye opening, incisor eruption and ear unfolding were recorded. Animals were observed for appearance of reflexes such as negative geotaxis, righting reflexes, fore- and hindlimb grasp, fore- and hindlimb placing, sensory reflexes and gait. In cases of negative geotaxis, surface righting and gait, the time to perform the reflex was also recorded daily. For examining motor coordination, we performed grid walking, footfault, rope suspension, rota-rod, inclined board and walk initiation tests. We found that enriched environment alone did not lead to marked alterations in the course of development. On the other hand, MSG treatment caused a slight delay in reflex development and a pronounced delay in weight gain and motor coordination maturation. This delay in most signs and tests could be reversed by enriched environment: MSG-treated pups kept under enriched conditions showed no weight retardation, no reflex delay in

  8. Pharmacokinetic drivers of toxicity for basic molecules: Strategy to lower pKa results in decreased tissue exposure and toxicity for a small molecule Met inhibitor

    International Nuclear Information System (INIS)

    Diaz, Dolores; Ford, Kevin A.; Hartley, Dylan P.; Harstad, Eric B.; Cain, Gary R.; Achilles-Poon, Kirsten; Nguyen, Trung; Peng, Jing; Zheng, Zhong; Merchant, Mark; Sutherlin, Daniel P.; Gaudino, John J.; Kaus, Robert; Lewin-Koh, Sock C.; Choo, Edna F.; Liederer, Bianca M.; Dambach, Donna M.

    2013-01-01

    Several toxicities are clearly driven by free drug concentrations in plasma, such as toxicities related to on-target exaggerated pharmacology or off-target pharmacological activity associated with receptors, enzymes or ion channels. However, there are examples in which organ toxicities appear to correlate better with total drug concentrations in the target tissues, rather than with free drug concentrations in plasma. Here we present a case study in which a small molecule Met inhibitor, GEN-203, with significant liver and bone marrow toxicity in preclinical species was modified with the intention of increasing the safety margin. GEN-203 is a lipophilic weak base as demonstrated by its physicochemical and structural properties: high LogD (distribution coefficient) (4.3) and high measured pKa (7.45) due to the basic amine (N-ethyl-3-fluoro-4-aminopiperidine). The physicochemical properties of GEN-203 were hypothesized to drive the high distribution of this compound to tissues as evidenced by a moderately-high volume of distribution (Vd > 3 l/kg) in mouse and subsequent toxicities of the compound. Specifically, the basicity of GEN-203 was decreased through addition of a second fluorine in the 3-position of the aminopiperidine to yield GEN-890 (N-ethyl-3,3-difluoro-4-aminopiperidine), which decreased the volume of distribution of the compound in mouse (Vd = 1.0 l/kg), decreased its tissue drug concentrations and led to decreased toxicity in mice. This strategy suggests that when toxicity is driven by tissue drug concentrations, optimization of the physicochemical parameters that drive tissue distribution can result in decreased drug concentrations in tissues, resulting in lower toxicity and improved safety margins. -- Highlights: ► Lower pKa for a small molecule: reduced tissue drug levels and toxicity. ► New analysis tools to assess electrostatic effects and ionization are presented. ► Chemical and PK drivers of toxicity can be leveraged to improve safety.

  9. Evaluation of occupational exposure to toxic metals released in the process of aluminum welding.

    Science.gov (United States)

    Matczak, Wanda; Gromiec, Jan

    2002-04-01

    The objective of this study was to evaluate occupational exposure to welding fumes and its elements on aluminum welders in Polish industry. The study included 52 MIG/Al fume samples and 18 TIG/Al samples in 3 plants. Air samples were collected in the breathing zone of welders (total and respirable dust). Dust concentration was determined gravimetrically, and the elements in the collected dust were determined by AAS. Mean time-weighted average (TWA) concentrations of the welding dusts/fumes and their components in the breathing zone obtained for different welding processes were, in mg/m3: MIG/Al fumes mean 6.0 (0.8-17.8), Al 2.1 (0.1-7.7), Mg 0.2 (TIG/Al fumes 0.7 (0.3-1.4), Al 0.17 (0.07-0.50). A correlation has been found between the concentration of the main components and the fume/dust concentrations in MIG/Al and TIG/Al fumes. Mean percentages of the individual components in MIG/Al fumes/dusts were Al: 30 (9-56) percent; Mg: 3 (1-5.6) percent; Mn: 0.2 (0.1-0.3) percent; Cu: 0.2 (welding methods, the nature of welding-related operations, and work environment conditions.

  10. Investigations of putative reproductive toxicity of low-dose exposures to vinclozolin in Wistar rats.

    Science.gov (United States)

    Flick, Burkhard; Schneider, Steffen; Melching-Kollmuss, Stephanie; Fussell, Karma C; Gröters, Sibylle; Buesen, Roland; Strauss, Volker; van Ravenzwaay, Bennard

    2017-04-01

    The current investigation examines whether the fungicide vinclozolin, which has an anti-androgenic mode of action, is capable of disrupting endocrine homeostasis at very low doses. The data generated clarify whether a non-monotonic dose-response relationship exists to enhance the current debate about the regulation of endocrine disruptors. Moreover, it is part of a series of investigations assessing the dose-response relationship of single and combined administration of anti-androgenic substances. A pre-postnatal in vivo study design was chosen which was compliant with regulatory testing protocols. The test design was improved by additional endpoints addressing hormone levels, morphology and histopathological examinations. Doses were chosen to represent an effect level (20 mg/kg bw/d), the current NOAEL (4 mg/kg bw/d), and a dose close to the "ADI" (0.005 mg/kg bw/d) for the detection of a possible non-monotonic dose-response curve. Anti-androgenic changes were observable at the effect level but not at lower exposures. Nipple/areola counts appeared to be the most sensitive measure of effect, followed by male sex organ weights at sexual maturation, and finally gross and histopathological findings. The results indicate the absence of evidence for effects at low or very low dose levels. A non-monotonic dose-response relationship was not evident.

  11. Exposure to Nicotine and Selected Toxicants in Cigarette Smokers Who Switched to Electronic Cigarettes: A Longitudinal Within-Subjects Observational Study

    Science.gov (United States)

    Gawron, Michal; Smith, Danielle M.; Peng, Margaret; Jacob, Peyton; Benowitz, Neal L.

    2017-01-01

    Introduction: Electronic cigarettes (e-cigarettes) are purported to deliver nicotine aerosol without any toxic combustion products present in tobacco smoke. In this longitudinal within-subjects observational study, we evaluated the effects of e-cigarettes on nicotine delivery and exposure to selected carcinogens and toxicants. Methods: We measured seven nicotine metabolites and 17 tobacco smoke exposure biomarkers in the urine samples of 20 smokers collected before and after switching to pen-style M201 e-cigarettes for 2 weeks. Biomarkers were metabolites of 13 major carcinogens and toxicants in cigarette smoke: one tobacco-specific nitrosamine (NNK), eight volatile organic compounds (1,3-butadiene, crotonaldehyde, acrolein, benzene, acrylamide, acrylonitrile, ethylene oxide, and propylene oxide), and four polycyclic aromatic hydrocarbons (naphthalene, fluorene, phenanthrene, and pyrene). Changes in urine biomarkers concentration were tested using repeated measures analysis of variance. Results: In total, 45% of participants reported complete abstinence from cigarette smoking at 2 weeks, while 55% reported continued smoking. Levels of total nicotine and some polycyclic aromatic hydrocarbon metabolites did not change after switching from tobacco to e-cigarettes. All other biomarkers significantly decreased after 1 week of using e-cigarettes (p e-cigarette may reduce user exposure to numerous toxicants and carcinogens otherwise present in tobacco cigarettes. Data on reduced exposure to harmful constituents that are present in tobacco cigarettes and e-cigarettes can aid in evaluating e-cigarettes as a potential harm reduction device. PMID:27613896

  12. Evaluation of a subchronic (13-week) oral toxicity study, preceded by an in utero exposure phase, with arachidonic acid oil derived from Mortierella alpina in rats

    NARCIS (Netherlands)

    Hempenius, R.A.; Lina, B.A.R.; Haggitt, R.C.

    2000-01-01

    Arachidonic acid oil (ARA-oil) derived from the fungus Mortierella alpina for use in infant nutrition was tested in a subchronic (13-week) oral toxicity study in rats, preceded by an in utero exposure phase. The ARA-oil was administered as admixture to the rodent diet at dose levels of 3000 ppm,

  13. Use of a custom RT-PCR array to analyze toxicity pathways at different life stages in Brown Norway Rat Brain following acute Toluene exposure.

    Science.gov (United States)

    To investigate the contribution of different life stages on response to toxicants, we utilized a custom designed RT-PCR array to examine the effects of acute exposure by oral gavage of the volatile organic solvent toluene (0.00, 0.65 or 1.0 glkg) in the brains of ma1e Brown Norwa...

  14. Identification of genomic biomarkers for anthracycline-induced cardiotoxicity in human iPSC-derived cardiomyocytes: an in vitro repeated exposure toxicity approach for safety assessment

    NARCIS (Netherlands)

    Chaudhari, U.; Nemade, H.; Wagh, V.; Ellis, J.K.; Srinivasan, S.; Louisse, J.

    2016-01-01

    The currently available techniques for the safety evaluation of candidate drugs are usually cost-intensive and time-consuming and are often insufficient to predict human relevant cardiotoxicity. The purpose of this study was to develop an in vitro repeated exposure toxicity methodology allowing the

  15. Linking embryo toxicity with genotoxic responses in the freshwater snail Physa acuta: single exposure to benzo(a)pyrene, fluoxetine, bisphenol A, vinclozolin and exposure to binary mixtures with benzo(a)pyrene.

    Science.gov (United States)

    Sánchez-Argüello, Paloma; Aparicio, Natalia; Fernández, Carlos

    2012-06-01

    Genotoxic effects on fauna after waterborne pollutant exposure have been demonstrated by numerous research programmes. Less effort has been focused on establishing relationship between genotoxicity and long-term responses at higher levels of biological organization. Taking into account that embryos may be more sensitive indicators of reproductive impairment than alterations in fertility, we have developed two assays in multiwell plates to address correlations between embryo toxicity and genotoxicity. The potential teratogenicity was assessed by analyzing abnormal development and mortality of Physa acuta at embryonic stage. Genotoxicity was measured by the micronucleus (MN) test using embryonic cells. Our results showed that linkage between genotoxicity and embryo toxicity depends on mechanisms of action of compounds under study. Embryo toxic responses showed a clear dose-related tendency whereas no clear dose-dependent effect was observed in micronucleus induction. The higher embryo toxicity was produced by benzo(a)pyrene exposure followed by fluoxetine and bisphenol A. Vinclozolin was the lower embryo toxic compound. Binary mixtures with BaP always resulted in higher embryo toxicity than single exposures but antagonistic effects were observed for MN induction. Benzo(a)pyrene produced the higher MN induction at 0.04 mg/L, which also produced clear embryo toxic effects. Fluoxetine did not induce cytogenetic effects but 0.25mg/L altered embryonic development. Bisphenol A significantly reduced hatchability at 0.5mg/L while MN induction appeared with higher treatments than those that start causing teratogenicity. Much higher concentration of vinclozolin (5mg/L) reduced hatchability and induced maximum MN formation. In conclusion, while validating one biomarker of genotoxicity and employing one ecologically relevant effect, we have evaluated the relative sensitivity of a freshwater mollusc for a range of chemicals. The embryo toxicity test is a starting point for the

  16. Mixtures of benzo(a)pyrene, dichlorodiphenyltrichloroethane and tributyltin are more toxic to neotropical fish Rhamdia quelen than isolated exposures.

    Science.gov (United States)

    Oliveira, Heloísa H P; Liebel, Samuel; Rossi, Stéfani C; Azevedo, Ana C B; Barrera, Ellie A L; Garcia, Juan Ramon Esquivel; Grötzner, Sônia Regina; Neto, Francisco Filipak; Randi, Marco A F; Ribeiro, Ciro A O

    2015-12-01

    activation of cell defenses after the sub-chronic exposure. TBT increased melanomacrophages counting in the 5-day experiment and the mixtures increased it in the 5 and 15-day experiments. Overall, the majority of the biomarkers pointed to a more toxic effect when these contaminants were combined, leading to unexpected toxicities compared to individual exposure scenarios. These findings are relevant considering environmental exposure conditions, since organisms are often exposed to different combinations of contaminants. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Lithium Improves Survival of PC12 Pheochromocytoma Cells in High-Density Cultures and after Exposure to Toxic Compounds

    Directory of Open Access Journals (Sweden)

    Cinzia Fabrizi

    2014-01-01

    Full Text Available Autophagy is an evolutionary conserved mechanism that allows for the degradation of long-lived proteins and entire organelles which are driven to lysosomes for digestion. Different kinds of stressful conditions such as starvation are able to induce autophagy. Lithium and rapamycin are potent autophagy inducers with different molecular targets. Lithium stimulates autophagy by decreasing the intracellular myo-inositol-1,4,5-triphosphate levels, while rapamycin acts through the inhibition of the mammalian target of rapamycin (mTOR. The correlation between autophagy and cell death is still a matter of debate especially in transformed cells. In fact, the execution of autophagy can protect cells from death by promptly removing damaged organelles such as mitochondria. Nevertheless, an excessive use of the autophagic machinery can drive cells to death via a sort of self-cannibalism. Our data show that lithium (used within its therapeutic window stimulates the overgrowth of the rat Pheochromocytoma cell line PC12. Besides, lithium and rapamycin protect PC12 cells from toxic compounds such as thapsigargin and trimethyltin. Taken together these data indicate that pharmacological activation of autophagy allows for the survival of Pheochromocytoma cells in stressful conditions such as high-density cultures and exposure to toxins.

  18. Evaluation of pulmonary and systemic toxicity following lung exposure to graphite nanoplates: a member of the graphene-based nanomaterial family.

    Science.gov (United States)

    Roberts, Jenny R; Mercer, Robert R; Stefaniak, Aleksandr B; Seehra, Mohindar S; Geddam, Usha K; Chaudhuri, Ishrat S; Kyrlidis, Angelos; Kodali, Vamsi K; Sager, Tina; Kenyon, Allison; Bilgesu, Suzan A; Eye, Tracy; Scabilloni, James F; Leonard, Stephen S; Fix, Natalie R; Schwegler-Berry, Diane; Farris, Breanne Y; Wolfarth, Michael G; Porter, Dale W; Castranova, Vincent; Erdely, Aaron

    2016-06-21

    Graphene, a monolayer of carbon, is an engineered nanomaterial (ENM) with physical and chemical properties that may offer application advantages over other carbonaceous ENMs, such as carbon nanotubes (CNT). The goal of this study was to comparatively assess pulmonary and systemic toxicity of graphite nanoplates, a member of the graphene-based nanomaterial family, with respect to nanoplate size. Three sizes of graphite nanoplates [20 μm lateral (Gr20), 5 μm lateral (Gr5), and m(2). At the low dose, none of the Gr materials induced toxicity. At the high dose, Gr20 and Gr5 exposure increased indices of lung inflammation and injury in lavage fluid and tissue gene expression to a greater degree and duration than Gr1 and CB. Gr5 and Gr20 showed no or minimal lung epithelial hypertrophy and hyperplasia, and no development of fibrosis by 2 months post-exposure. In addition, the aorta and liver inflammatory and acute phase genes were transiently elevated in Gr5 and Gr20, relative to Gr1. Pulmonary and systemic toxicity of graphite nanoplates may be dependent on lateral size and/or surface reactivity, with the graphite nanoplates > 5 μm laterally inducing greater toxicity which peaked at the early time points post-exposure relative to the 1-2 μm graphite nanoplate.

  19. Evaluation of the use of human hair for biomonitoring the deficiency of essential and exposure to toxic elements

    International Nuclear Information System (INIS)

    Rodrigues, Jairo L.; Batista, Bruno L.; Nunes, Juliana A.; Passos, Carlos J.S.; Barbosa, Fernando

    2008-01-01

    Monitoring the nutritional status of essential elements and assessing exposure of individuals to toxic elements is of great importance for human health. Thus, the appropriate selection and measurement of biomarkers of internal dose is of critical importance. Due to their many advantages, hair samples have been widely used to assess human exposure to different contaminants. However, the validity of this biomarker in evaluating the level of trace elements in the human body is debatable. In the present study, we evaluated the relationship between levels of trace elements in hair and whole blood or plasma in a Brazilian population. Hair, blood and plasma were collected from 280 adult volunteers for metal determination. An ICP-MS was used for sample analysis. Manganese, copper, lead and strontium levels in blood varied from 5.1 to 14.7, from 494.8 to 2383.8, from 5.9 to 330.1 and from 11.6 to 87.3 μg/L, respectively. Corresponding levels in hair varied from 0.05 to 6.71, from 0.02 to 37.59, from 0.02 to 30.63 and from 0.9 to 12.6 μg/g. Trace element levels in plasma varied from 0.07 to 8.62, from 118.2 to 1577.7 and from 2.31 to 34.2 μg/L for Mn, Cu and Sr, respectively. There was a weak correlation (r = 0.22, p < 0.001) between lead levels in hair and blood. Moreover, copper and strontium levels in blood correlate with those levels in plasma (r = 0.64 , p < 0.001 for Cu) and (r = 0.22, p < 0.05 for Sr). However, for Cu, Mn and Sr there was no correlation between levels in hair and blood. Our findings suggest that while the idea of measuring trace elements in hair is attractive, hair is not an appropriate biomarker for evaluating Cu, Mn and Sr deficiency or Pb exposure

  20. Evaluation of the use of human hair for biomonitoring the deficiency of essential and exposure to toxic elements

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Jairo L.; Batista, Bruno L.; Nunes, Juliana A.; Passos, Carlos J.S. [Laboratorio de Toxicologia e Essencialidade de Metais, Depto. de Analises Clinicas, Toxicologicas e Bromatologicas, Faculdade de Ciencias Farmaceuticas de Ribeirao Preto-USP, Avenida do Cafe s/n, Monte Alegre, 14040-903, Ribeirao Preto-SP (Brazil); Barbosa, Fernando [Laboratorio de Toxicologia e Essencialidade de Metais, Depto. de Analises Clinicas, Toxicologicas e Bromatologicas, Faculdade de Ciencias Farmaceuticas de Ribeirao Preto-USP, Avenida do Cafe s/n, Monte Alegre, 14040-903, Ribeirao Preto-SP (Brazil)], E-mail: fbarbosa@fcfrp.usp.br

    2008-11-01

    Monitoring the nutritional status of essential elements and assessing exposure of individuals to toxic elements is of great importance for human health. Thus, the appropriate selection and measurement of biomarkers of internal dose is of critical importance. Due to their many advantages, hair samples have been widely used to assess human exposure to different contaminants. However, the validity of this biomarker in evaluating the level of trace elements in the human body is debatable. In the present study, we evaluated the relationship between levels of trace elements in hair and whole blood or plasma in a Brazilian population. Hair, blood and plasma were collected from 280 adult volunteers for metal determination. An ICP-MS was used for sample analysis. Manganese, copper, lead and strontium levels in blood varied from 5.1 to 14.7, from 494.8 to 2383.8, from 5.9 to 330.1 and from 11.6 to 87.3 {mu}g/L, respectively. Corresponding levels in hair varied from 0.05 to 6.71, from 0.02 to 37.59, from 0.02 to 30.63 and from 0.9 to 12.6 {mu}g/g. Trace element levels in plasma varied from 0.07 to 8.62, from 118.2 to 1577.7 and from 2.31 to 34.2 {mu}g/L for Mn, Cu and Sr, respectively. There was a weak correlation (r = 0.22, p < 0.001) between lead levels in hair and blood. Moreover, copper and strontium levels in blood correlate with those levels in plasma (r = 0.64 , p < 0.001 for Cu) and (r = 0.22, p < 0.05 for Sr). However, for Cu, Mn and Sr there was no correlation between levels in hair and blood. Our findings suggest that while the idea of measuring trace elements in hair is attractive, hair is not an appropriate biomarker for evaluating Cu, Mn and Sr deficiency or Pb exposure.

  1. Effect of concentration, exposure time, temperature, and relative humidity on the toxicity of sulfur dioxide to the spores of Botrytis cinerea

    Energy Technology Data Exchange (ETDEWEB)

    Couey, H.M.; Uota, M.

    1961-12-01

    When spores of Botrytis cinerea are exposed to SO/sub 2/ gas, the subsequent reduction in spore germination is quantitatively proportional to the SO/sub 2/ concentration and the exposure time. The toxicity of SO/sub 2/ increases with increasing relative humidity. In an atmosphere of 96% RH, SO/sub 2/ is more than 20 times as effective as at 75% RH. The toxicity also increases about 1.5 times for each 10/sup 0/C rise in temperature between 0/sup 0/ and 30/sup 0/C. 8 references, 4 figures, 1 table.

  2. A comparison of Reduced Life Expectancy (RLE) model with Haber's Rule to describe effects of exposure time on toxicity

    International Nuclear Information System (INIS)

    Verma, Vibha; Yu, Qiming J.; Connell, Des W.

    2015-01-01

    The Reduced Life Expectancy (RLE) Model (LC 50  = [ln(NLE) – ln(LT 50 )]/d) has been proposed as an alternative to Haber's Rule. The model is based on a linear relationship between LC 50 (Lethal Exposure Concentration) and lnLT 50 (Lethal Exposure Time) and uses NLE (Normal Life Expectancy) as a limiting point as well as a long term data point (where d is a constant). The purposes of this paper were to compare the RLE Model with Haber's Rule with available toxicity data and to evaluate the strengths and weaknesses of each approach. When LT 50 is relatively short and LC 50 is high, Haber's Rule is consistent with the RLE model. But the difference between the two was evident in the situation when LT 50 is relatively long and LC 50 is low where the RLE model is a marked departure from Haber's Rule. The RLE Model can be used to appropriately evaluate long term effects of exposure. - Highlights: • The strength and weakness of Haber's Rule in relation to the RLE model is needed. • Haber's Rule now used universally is quite inappropriate for environmental toxicity. • Normal life expectancy, a new parameter l is used to evaluate effects of exposure time on toxicity. • According to RLE model when LC 50 approaches zero, then LT 50  = Normal Life Expectancy. • The RLE model can be used to evaluate long term effects of exposure-accurately and easily. - The RLE approach is a more appropriate alternative particularly to evaluate long term effects of exposure. It can be easily used to estimate long term effects of exposure

  3. Accumulation and Toxicity of CuO and ZnO Nanoparticles through Waterborne and Dietary Exposure of Goldfish (Carassius auratus)

    Science.gov (United States)

    Ates, Mehmet; Arslan, Zikri; Demir, Veysel; Daniels, James; Farah, Ibrahim O.

    2014-01-01

    Dietary and waterborne exposure to CuO and ZnO nanoparticles (NPs) was conducted using a simplified model of an aquatic food chain consisting of zooplankton (Artemia salina) and goldfish (Carassius auratus) to determine bioaccumulation, toxic effects and particle transport through trophic levels. Artemia contaminated with NPs were used as food in dietary exposure. Fish were exposed to suspensions of the NPs in waterborne exposure. ICP-MS analysis showed that accumulation primarily occurred in the intestine, followed by the gills and liver. Dietary uptake was lower, but was found to be a potential pathway for transport of NPs to higher organisms. Waterborne exposure resulted in about a tenfold higher accumulation in the intestine. The heart, brain and muscle tissue had no significant Cu or Zn. However, concentrations in muscle increased with NP concentration, which was ascribed to bioaccumulation of Cu and Zn released from NPs. Free Cu concentration in the medium was always higher than that of Zn, indicating CuO NPs dissolved more readily. ZnO NPs were relatively benign, even in waterborne exposure (p≥0.05). In contrast, CuO NPs were toxic. Malondialdehyde levels in the liver and gills increased substantially (p<0.05). Despite lower Cu accumulation, the liver exhibited significant oxidative stress, which could be from chronic exposure to Cu ions. PMID:24860999

  4. Personnel monitoring for beta rays

    International Nuclear Information System (INIS)

    Piesch, E.; Johns, T.F.

    1983-01-01

    The practical considerations which have to be taken into account in the design of personnel monitors intended to measure doses resulting from exposure to beta rays are discussed. These include the measurement of doses in situations involving either fairly uniform or non-uniform irradiation and of doses to the male gonads. (UK)

  5. The margin of internal exposure (MOIE) concept for dermal risk assessment based on oral toxicity data - A case study with caffeine.

    Science.gov (United States)

    Bessems, Jos G M; Paini, Alicia; Gajewska, Monika; Worth, Andrew

    2017-12-01

    Route-to-route extrapolation is a common part of human risk assessment. Data from oral animal toxicity studies are commonly used to assess the safety of various but specific human dermal exposure scenarios. Using theoretical examples of various user scenarios, it was concluded that delineation of a generally applicable human dermal limit value is not a practicable approach, due to the wide variety of possible human exposure scenarios, including its consequences for internal exposure. This paper uses physiologically based kinetic (PBK) modelling approaches to predict animal as well as human internal exposure dose metrics and for the first time, introduces the concept of Margin of Internal Exposure (MOIE) based on these internal dose metrics. Caffeine was chosen to illustrate this approach. It is a substance that is often found in cosmetics and for which oral repeated dose toxicity data were available. A rat PBK model was constructed in order to convert the oral NOAEL to rat internal exposure dose metrics, i.e. the area under the curve (AUC) and the maximum concentration (C max ), both in plasma. A human oral PBK model was constructed and calibrated using human volunteer data and adapted to accommodate dermal absorption following human dermal exposure. Use of the MOIE approach based on internal dose metrics predictions provides excellent opportunities to investigate the consequences of variations in human dermal exposure scenarios. It can accommodate within-day variation in plasma concentrations and is scientifically more robust than assuming just an exposure in mg/kg bw/day. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Effects of human performance methods of the radiation exposure of the task personnel during the inspection of steam generator heat tubes

    International Nuclear Information System (INIS)

    Wilkes, Bernd; Bienentreu, Robert

    2008-01-01

    Westinghouse has implemented the so called human performance philosophy for specific scopes of work. Human performance is supposed to establish and support personnel behavior aimed to a safe and reliable operation of the plant. The overall goal is the prevention of errors. Every action deviating from the expected behavior is defined as an error, independent of the consequences. The accident statistics has shown that every severe accident was preceded by hundreds of events without consequences. The implementation of these techniques is demonstrated using the process of steam generator heat tube inspection. According to the ALARA principle a lot of effort was concentrated on dose reduction for the personnel, including constructive (improved testing probes, improved manipulator, etc.) and administrative measures.

  7. Antimony Toxicity

    Directory of Open Access Journals (Sweden)

    Shyam Sundar

    2010-12-01

    Full Text Available Antimony toxicity occurs either due to occupational exposure or during therapy. Occupational exposure may cause respiratory irritation, pneumoconiosis, antimony spots on the skin and gastrointestinal symptoms. In addition antimony trioxide is possibly carcinogenic to humans. Improvements in working conditions have remarkably decreased the incidence of antimony toxicity in the workplace. As a therapeutic, antimony has been mostly used for the treatment of leishmaniasis and schistosomiasis. The major toxic side-effects of antimonials as a result of therapy are cardiotoxicity (~9% of patients and pancreatitis, which is seen commonly in HIV and visceral leishmaniasis co-infections. Quality control of each batch of drugs produced and regular monitoring for toxicity is required when antimonials are used therapeutically.

  8. Toxic effects of maternal zearalenone exposure on intestinal oxidative stress, barrier function, immunological and morphological changes in rats.

    Directory of Open Access Journals (Sweden)

    Min Liu

    Full Text Available The present study was conducted to investigate the effects of maternal zearalenone (ZEN exposure on the intestine of pregnant Sprague-Dawley (SD rats and its offspring. Ninety-six pregnant SD rats were randomly divided into four groups and were fed with diets containing ZEN at concentrations of 0.3 mg/kg, 48.5 mg/kg, 97.6 mg/kg or 146.0 mg/kg from gestation days (GD 1 to 7. All rats were fed with mycotoxin-free diet until their offspring were weaned at three weeks of age. The small intestinal fragments from pregnant rats at GD8, weaned dams and pups were collected and studied for toxic effects of ZEN on antioxidant status, immune response, expression of junction proteins, and morphology. The results showed that ZEN induced oxidative stress, affected the villous structure and reduced the expression of junction proteins claudin-4, occludin and connexin43 (Cx43 in a dose-dependent manner in pregnant rats. Different effects on the expression of cytokines were also observed both in mRNA and protein levels in these pregnant groups. Ingestion of high levels of ZEN caused irreversible damage in weaned dams, such as oxidative stress, decreased villi hight and low expression of junction proteins and cytokines. Decreased expression of jejunal interleukin-8 (IL-8 and increased expression of gastrointestinal glutathione peroxidase (GPx2 mRNA were detected in weaned offspring, indicating long-term damage caused by maternal ZEN. We also found that the Nrf2 expression both in mRNA and protein levels were up-regulated in the ZEN-treated groups of pregnant dams and the high-dose of ZEN group of weaned dams. The data indicate that modulation of Nrf2-mediated pathway is one of mechanism via which ZEN affects gut wall antioxidant and inflammatory responses.

  9. Alcohol-antiretroviral interactive toxicity beliefs as a potential barrier to HIV pre-exposure prophylaxis among men who have sex with men

    OpenAIRE

    Seth C Kalichman; Lisa Eaton

    2017-01-01

    Abstract Introduction: Pre-exposure prophylaxis (PrEP) offers as much as 90% protection against HIV transmission. However, the effectiveness of PrEP depends on uptake and adherence to even intermittent dosing. Along with intoxication leading to unintentional non-adherence, believing that alcohol mixed with pharmaceuticals is harmful (i.e., interactive toxicity beliefs) may lead to poor uptake and intentional non-adherence. Methods: HIV-negative sexually active men who have sex with men (N?=?2...

  10. Exposure to Nicotine and Selected Toxicants in Cigarette Smokers Who Switched to Electronic Cigarettes: A Longitudinal Within-Subjects Observational Study.

    Science.gov (United States)

    Goniewicz, Maciej L; Gawron, Michal; Smith, Danielle M; Peng, Margaret; Jacob, Peyton; Benowitz, Neal L

    2017-02-01

    Electronic cigarettes (e-cigarettes) are purported to deliver nicotine aerosol without any toxic combustion products present in tobacco smoke. In this longitudinal within-subjects observational study, we evaluated the effects of e-cigarettes on nicotine delivery and exposure to selected carcinogens and toxicants. We measured seven nicotine metabolites and 17 tobacco smoke exposure biomarkers in the urine samples of 20 smokers collected before and after switching to pen-style M201 e-cigarettes for 2 weeks. Biomarkers were metabolites of 13 major carcinogens and toxicants in cigarette smoke: one tobacco-specific nitrosamine (NNK), eight volatile organic compounds (1,3-butadiene, crotonaldehyde, acrolein, benzene, acrylamide, acrylonitrile, ethylene oxide, and propylene oxide), and four polycyclic aromatic hydrocarbons (naphthalene, fluorene, phenanthrene, and pyrene). Changes in urine biomarkers concentration were tested using repeated measures analysis of variance. In total, 45% of participants reported complete abstinence from cigarette smoking at 2 weeks, while 55% reported continued smoking. Levels of total nicotine and some polycyclic aromatic hydrocarbon metabolites did not change after switching from tobacco to e-cigarettes. All other biomarkers significantly decreased after 1 week of using e-cigarettes (p knowledge, this is the first study that demonstrates that substituting tobacco cigarettes with an e-cigarette may reduce user exposure to numerous toxicants and carcinogens otherwise present in tobacco cigarettes. Data on reduced exposure to harmful constituents that are present in tobacco cigarettes and e-cigarettes can aid in evaluating e-cigarettes as a potential harm reduction device. © The Author 2016. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Annual course of retraining for the occupational exposure personnel of the laboratory of internal dosimetry; Curso anual de reentrenamiento para el POE del laboratorio de dosimetria interna

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro L, M.M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2002-09-15

    The general objective of this report is to instruct the personnel in the basic concepts of radiological protection and in the Manual of Procedures of Radiological Safety of the Laboratory of Internal Dosimetry. Also, to exchange experiences during the activities that are carried out in the laboratory and in the knowledge of abnormal situations. The referred Manual consists of 14 procedures and 5 instructions which are listed in annex of this document. The content of this course consists of three topics: 1. Basic principles of radiological protection to reduce the received dose equivalent. 2. Use of radiation measurer equipment. 3. Emergency procedures of the laboratory of internal dosimetry. (Author)

  12. Alcohol-antiretroviral interactive toxicity beliefs as a potential barrier to HIV pre-exposure prophylaxis among men who have sex with men.

    Science.gov (United States)

    Kalichman, Seth C; Eaton, Lisa

    2017-07-17

    Pre-exposure prophylaxis (PrEP) offers as much as 90% protection against HIV transmission. However, the effectiveness of PrEP depends on uptake and adherence to even intermittent dosing. Along with intoxication leading to unintentional non-adherence, believing that alcohol mixed with pharmaceuticals is harmful (i.e., interactive toxicity beliefs) may lead to poor uptake and intentional non-adherence. HIV-negative sexually active men who have sex with men ( N  = 272) at a large Gay Pride event in Atlanta, GA, completed anonymous surveys of demographic characteristics, sexual behaviour, alcohol use and PrEP-related alcohol interactive toxicity beliefs. A total of 118 (43%) men surveyed had two or more male sex partners and condomless anal sex in the previous six months. Alcohol use was reported by over 90% of men and it was common for participants to believe that mixing alcohol and antiretrovirals is toxic; 75% endorsed at least one interactive toxicity belief. Among the 118 men who had engaged in condomless anal sex and had multiple sex partners, one in three stated that they were not interested in PrEP and men not interested in PrEP were significantly more likely to binge drink and hold interactive toxicity beliefs. These results mirror studies that find interactive toxicity beliefs are a potent predictor of intentional antiretroviral non-adherence among people living with HIV and suggest interactive toxicity beliefs may impede PrEP uptake and adherence. Messages to increase PrEP awareness and adherence may also take steps to counter erroneous beliefs about mixing alcohol with antiretrovirals in the context of PrEP.

  13. Increased Suicide Risk among Workers following Toxic Metal Exposure at the Paducah Gaseous Diffusion Plant From 1952 to 2003: A Cohort Study

    Directory of Open Access Journals (Sweden)

    LW Figgs

    2011-09-01

    Full Text Available Background: Suicide is a problem worldwide and occupation is an important risk factor. In the last decade, 55 200 deaths in the US were attributed to occupational risk factors. Objective: To determine if toxic metal exposure was associated with suicide risk among Paducah gaseous diffusion plant (PGDP workers. Methods: We assembled a cohort of 6820 nuclear industry workers employed from 1952 to 2003. A job-specific exposure matrix (JEM was used to determine metal exposure likelihood. Uranium exposure was also assessed by urinalysis. All suicide/self-injury International Classification for Disease (ICD codes were used to identify suicides. Standardized mortality ratios (SMR, odds ratios (OR, and hazard ratios (HR were used to estimate suicide risk. Results: PGDP suicide victims typically were younger white men. Within exposure likelihood categories, several suicide SMRs were typically elevated for several metals. Only beryllium exposure likelihood was associated with an increased HR. Uranium urine concentration was associated with an elevated suicide risk after stratification by urinalysis frequency. Conclusion: Suicide risk is associated with uranium exposure.

  14. An Epidemiologic Investigation of Health Effects in Air Force Personnel Following Exposure to Herbicides. Volume I: 1997 Follow-up Examination Results

    National Research Council Canada - National Science Library

    Michalek, J

    2000-01-01

    ... attributable to exposure to herbicides exist in veterans of Operation Ranch Hand Operation. Ranch Hand was the unit responsible for the aerial spraying of herbicides, including Herbicide Orange, in Vietnam from 1961 to 1971...

  15. Personnel training and certification

    International Nuclear Information System (INIS)

    Whittemore, W.L.

    1976-01-01

    In order to make the full benefits of neutron radiography available in the nondestructive test (NDT) field, it has been necessary to formalize its application. A group under the Penetrating Radiation Committee of the American Society for Nondestructive Testing (ASNT) was organized to prepare a recommended practice for neutron radiography. The recommended practices require the establishment of an appropriate certification program. The requirements on the employer to establish and maintain a qualification and certification program are outlined. To conduct a program of nondestructive testing using neutron radiography requires the usual three levels of qualified and certified personnel. The program is administered by a Level III person. Routine exposure, reviews, and reporting of test results are the responsibilities of Level I and Level II personnal. The amount of training and nature of the required practical examination are also specified. The recommended practices document assures users that NDT work in the field of neutron radiography is performed by qualified personnel. Although no training courses are available to provide experience in the depth required by the recommended practices document, SNT-TC-1A, short courses are provided at a number of locations to familarize user's representatives with the interpretation of neutron radiographs and capabilities and limitations of the technique

  16. 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.

  17. Evaluating X-ray absorption of nano-bismuth oxide ointment for decreasing risks associated with X-ray exposure among operating room personnel and radiology experts

    Directory of Open Access Journals (Sweden)

    M. Rashidi

    2015-12-01

      Conclusion: It seems that due to higher atomic number and lower toxicity, Bi2O3 nanoparticles have better efficiency in X-ray absorbtion, comparing to the lead. Cream and ointment of bismuth oxide nanoparticles can be used as X-ray absorbant for different professions such as physicians, dentists, radiology experts, and operating room staff and consequently increase health and safety of these employees.

  18. Increased risk for congenital heart defects in children carrying the ABCB1 Gene C3435T polymorphism and maternal periconceptional toxicants exposure.

    Directory of Open Access Journals (Sweden)

    Chuan Wang

    Full Text Available BACKGROUNDS: The etiology of congenital heart defect (CHD is commonly believed to involve the interaction of multiple environmental and genetic factors. This study aimed to explore the joint effects of the ABCB1 gene C3435T polymorphism and maternal periconceptional toxicants exposure on the CHD risk in a Han Chinese population. METHODS: An age and gender matched case-control study with standardized data collection involving 201 pairs was conducted. Periconceptional toxicants exposure was obtained through a structured questionnaire. A job exposure matrix (JEM was used for toxicants exposure assessment. Genotyping of the ABCB1 C3435T polymorphism was performed by sequencing. Logistic regression analysis was performed to assess the joint effects of the ABCB1 gene C3435T polymorphism and toxicants exposure on the risk of CHD. Placenta tissues and umbilical cords were collected to investigate the impact of C3435T polymorphism on the transcription and translation activities of ABCB1 gene. RESULTS: MATERNAL PERICONCEPTIONAL EXPOSURES TO PHTHALATES (ADJUSTED OR: 1.6; 95%CI: 1.0-2.6 and alkylphenolic compounds (adjusted OR:1.8; 95%CI:1.1-3.0 were associated with a higher incidence of CHDs in general. More cases were carriers of the ABCB1 CC/CT genotypes (OR: 2.0, 95%CI: 1.1-3.5, P-value: 0.021. Children carrying the CC/CT genotype and periconceptionally exposed to phthalates and alkylphenolic compounds suffered almost 3.5-fold increased risk of having CHD than non-exposed children with TT genotype (adjusted OR: 3.5, 95%CI: 1.5-7.9, P-value: 0.003, and the OR changed to 4.4 for septal defects (adjusted OR: 4.4,95%CI:1.8-10.9,P-value:0.001. The ABCB1 mRNA expression of the TT genotype was significantly higher than that of the CC genotype (P = 0.03. Compared with TT genotype, lower P-glycoprotein expression was observed for the CC/CT genotypes. CONCLUSION: The C3435T polymorphism in the ABCB1 gene of fetus increases the risks of CHD in a Han Chinese

  19. The toxicity and anesthetic effect of sodium hydroxybutyrate and ketamine at different periods of the combined radiation injuy , burn trauma and x-ray exposure

    International Nuclear Information System (INIS)

    Il'yuchenok, T.Yu.; Rasulev, B.K.; Moiseeva, L.A.

    1985-01-01

    Mongreal mice have been used to study animal sensitivity under the conditions of combined radiation injury (CRI), separate burn and X-ray effect to sodium hydroxybutyrate and ketamine. It is shown that while administering these anes thetics the differences in the organism reaction depend on the stage of injury and form of exposure. The changes in anesthesia duration in the first days (1-st - 4-th) after radiation exposure are contrary to those at combined radiation-thermal injury and separate burn trauma. The anesthetic effect of ketamine increases under the conditions of combined radiation-thermal injury and is not changed at separate exposures; its toxicity, on the contrary, on the 30-th day after burn and irradiation is increased

  20. HABIT, Toxic and Radioactive Release Hazards in Reactor Control Room

    International Nuclear Information System (INIS)

    Stage, S.A.

    2005-01-01

    1 - Description of program or function: HABIT is a package of computer codes designed to be used for the evaluation of control room habitability in the event of an accidental release of toxic chemicals or radioactive materials. 2 - Methods: Given information about the design of a nuclear power plant, a scenario for the release of toxic or radionuclides, and information about the air flows and protection systems of the control room, HABIT can be used to estimate the chemical exposure or radiological dose to control room personnel

  1. Recent research on Gulf War illness and other health problems in veterans of the 1991 Gulf War: Effects of toxicant exposures during deployment

    Science.gov (United States)

    White, Roberta F.; Steele, Lea; O’Callaghan, James P.; Sullivan, Kimberly; Binns, James H.; Golomb, Beatrice A.; Bloom, Floyd E.; Bunker, James A.; Crawford, Fiona; Graves, Joel C.; Hardie, Anthony; Klimas, Nancy; Knox, Marguerite; Meggs, William J.; Melling, Jack; Philbert, Martin A.; Grashow, Rachel

    2015-01-01

    Veterans of Operation Desert Storm/Desert Shield – the 1991 Gulf War (GW) – are a unique population who returned from theater with multiple health complaints and disorders. Studies in the U.S. and elsewhere have consistently concluded that approximately 25–32% of this population suffers from a disorder characterized by symptoms that vary somewhat among individuals and include fatigue, headaches, cognitive dysfunction, musculoskeletal pain, and respiratory, gastrointestinal and dermatologic complaints. Gulf War illness (GWI) is the term used to describe this disorder. In addition, brain cancer occurs at increased rates in subgroups of GW veterans, as do neuropsychological and brain imaging abnormalities. Chemical exposures have become the focus of etiologic GWI research because nervous system symptoms are prominent and many neurotoxicants were present in theater, including organophosphates (OPs), carbamates, and other pesticides; sarin/cyclosarin nerve agents, and pyridostigmine bromide (PB) medications used as prophylaxis against chemical warfare attacks. Psychiatric etiologies have been ruled out. This paper reviews the recent literature on the health of 1991 GW veterans, focusing particularly on the central nervous system and on effects of toxicant exposures. In addition, it emphasizes research published since 2008, following on an exhaustive review that was published in that year that summarizes the prior literature (RACGWI, 2008). We conclude that exposure to pesticides and/or to PB are causally associated with GWI and the neurological dysfunction in GW veterans. Exposure to sarin and cyclosarin and to oil well fire emissions are also associated with neurologically based health effects, though their contribution to development of the disorder known as GWI is less clear. Gene-environment interactions are likely to have contributed to development of GWI in deployed veterans. The health consequences of chemical exposures in the GW and other conflicts have

  2. In-vitro Cell Exposure Studies for the Assessment of Nanoparticle Toxicity in the Lung - A Dialogue between Aerosol Science and Biology

    Energy Technology Data Exchange (ETDEWEB)

    Hanns-Rudolf, Paur; Cassee, Flemming R.; Teeguarden, Justin G.; Fissan, Heinz; Diabate, Silvia; Aufderheide, M.; Kreyling, Wolfgang G.; Hanninen, Otto; Kasper, G.; Riediker, Michael; Rothen-Rutishauser, Barbara; Schmid, Otmar

    2011-10-01

    The rapid introduction of engineered nanostructured materials into numerous industrial and consumer products will result in enhanced exposure to engineered nanoparticles. Workplace exposure has been identified as the most likely source of uncontrolled inhalation of engineered aerosolized nanoparticles, but release of engineered nanoparticles may occur at any stage of the lifecycle of consumer products. The dynamic development of new nanomaterials with possibly unknown toxicological effects poses a challenge for the assessment of nanoparticle induced toxicity and safety. In this consensus document from a workshop on in-vitro cell systems for nanotoxicity testing an overview is given of the main issues concerning inhalation exposure to nanoparticles, lung physiology, nanoparticle-related biological mechanisms, in-vitro cell exposure systems for nanoparticles and social aspects of nanotechnology. The workshop participants recognized the large potential of in-vitro cell exposure systems for reliable, high-throughput screening of nanotoxicity. For the investigation of pulmonary nanotoxicity, a strong preference was expressed for air-liquid interface (ALI) cell exposure systems (rather than submerged cell exposure systems) as they closely resemble in-vivo conditions in the lungs and they allow for unaltered and dosimetrically accurate delivery of aerosolized nanoparticles to the cells. The members of the workshop believe that further advances in in-vitro cell exposure studies would be greatly facilitated by a more active role of the aerosol scientists. The technical know-how for developing and running ALI in-vitro exposure systems is available in the aerosol community and at the same time biologists/toxicologists are required for proper assessment of the biological impact of nanoparticles.

  3. In-vitro Cell Exposure Studies for the Assessment of Nanoparticle Toxicity in the Lung - A Dialogue between Aerosol Science and Biology

    International Nuclear Information System (INIS)

    Hanns-Rudolf, Paur; Cassee, Flemming R.; Teeguarden, Justin G.; Fissan, Heinz; Diabate, Silvia; Aufderheide, M.; Kreyling, Wolfgang G.; Hanninen, Otto; Kasper, G.; Riediker, Michael; Rothen-Rutishauser, Barbara; Schmid, Otmar

    2011-01-01

    The rapid introduction of engineered nanostructured materials into numerous industrial and consumer products will result in enhanced exposure to engineered nanoparticles. Workplace exposure has been identified as the most likely source of uncontrolled inhalation of engineered aerosolized nanoparticles, but release of engineered nanoparticles may occur at any stage of the lifecycle of consumer products. The dynamic development of new nanomaterials with possibly unknown toxicological effects poses a challenge for the assessment of nanoparticle induced toxicity and safety. In this consensus document from a workshop on in-vitro cell systems for nanotoxicity testing an overview is given of the main issues concerning inhalation exposure to nanoparticles, lung physiology, nanoparticle-related biological mechanisms, in-vitro cell exposure systems for nanoparticles and social aspects of nanotechnology. The workshop participants recognized the large potential of in-vitro cell exposure systems for reliable, high-throughput screening of nanotoxicity. For the investigation of pulmonary nanotoxicity, a strong preference was expressed for air-liquid interface (ALI) cell exposure systems (rather than submerged cell exposure systems) as they closely resemble in-vivo conditions in the lungs and they allow for unaltered and dosimetrically accurate delivery of aerosolized nanoparticles to the cells. The members of the workshop believe that further advances in in-vitro cell exposure studies would be greatly facilitated by a more active role of the aerosol scientists. The technical know-how for developing and running ALI in-vitro exposure systems is available in the aerosol community and at the same time biologists/toxicologists are required for proper assessment of the biological impact of nanoparticles.

  4. Evaluation of the Possible Sources and Controlling Factors of Toxic Metals/Metalloids in the Florida Everglades and Their Potential Risk of Exposure.

    Science.gov (United States)

    Li, Yanbin; Duan, Zhiwei; Liu, Guangliang; Kalla, Peter; Scheidt, Daniel; Cai, Yong

    2015-08-18

    The Florida Everglades is an environmentally sensitive wetland ecosystem with a number of threatened and endangered fauna species susceptible to the deterioration of water quality. Several potential toxic metal sources exist in the Everglades, including farming, atmospheric deposition, and human activities in urban areas, causing concerns of potential metal exposure risks. However, little is known about the pollution status of toxic metals/metalloids of potential concern, except for Hg. In this study, eight toxic metals/metalloids (Cd, Cr, Pb, Ni, Cu, Zn, As, and Hg) in Everglades soils were investigated in both dry and wet seasons. Pb, Cr, As, Cu, Cd, and Ni were identified to be above Florida SQGs (sediment quality guidelines) at a number of sampling sites, particularly Pb, which had a level of potential risk to organisms similar to that of Hg. In addition, a method was developed for quantitative source identification and controlling factor elucidation of toxic metals/metalloids by introducing an index, enrichment factor (EF), in the conventional multiple regression analysis. EFs represent the effects of anthropogenic sources on metals/metalloids in soils. Multiple regression analysis showed that Cr and Ni were mainly controlled by anthropogenic loading, whereas soil characteristics, in particular natural organic matter (NOM), played a more important role for Hg, As, Cd, and Zn. NOM may control the distribution of these toxic metals/metalloids by affecting their mobility in soils. For Cu and Pb, the effects of EFs and environmental factors are comparable, suggesting combined effects of loading and soil characteristics. This study is the first comprehensive research with a vast amount of sampling sites on the distribution and potential risks of toxic metals/metalloids in the Everglades. The finding suggests that in addition to Hg other metals/metalloids could also potentially be an environmental problem in this wetland ecosystem.

  5. E-cigarette puffing patterns associated with high and low nicotine e-liquid strength: effects on toxicant and carcinogen exposure.

    Science.gov (United States)

    Cox, Sharon; Kośmider, Leon; McRobbie, Hayden; Goniewicz, Maciej; Kimber, Catherine; Doig, Mira; Dawkins, Lynne

    2016-09-20

    Contrary to intuition, use of lower strength nicotine e-liquids might not offer reduced health risk if compensatory puffing behaviour occurs. Compensatory puffing (e.g. more frequent, longer puffs) or user behaviour (increasing the wattage) can lead to higher temperatures at which glycerine and propylene glycol (solvents used in e-liquids) undergo decomposition to carbonyl compounds, including the carcinogens formaldehyde and acetaldehyde. This study aims to document puffing patterns and user behaviour associated with using high and low strength nicotine e-liquid and associated toxicant/carcinogen exposure in experienced e-cigarette users (known as vapers herein). A counterbalanced repeated measures design. Non-tobacco smoking vapers; have used an e-cigarette for ≥3 months; currently using nicotine strength e-liquid ≥12mg/mL and a second or third generation device. This study will measure puffing patterns in vapers whilst they use high and low strength nicotine e-liquid under fixed and user-defined settings, each for a week. The 4 counterbalanced conditions are: i) low strength (6mg/mL), fixed settings; ii) low strength user-defined settings; iii) high strength (18mg/mL) fixed settings; iv) high strength user-defined settings. Biomarkers of exposure to toxicants and carcinogens will be measured in urine. In the second phase of this study, toxicant yields will be measured in aerosol generated using a smoking machine operated to replicate the puffing behaviours of each participant. i) Puffing patterns (mean puff number, puff duration, inter-puff interval and mL of liquid consumed) and user behaviour (changes to device settings: voltage and air-flow) associated with using high and low strength nicotine e-liquid. ii) Toxicant/carcinogen exposure associated with the puffing patterns/device settings used by our participants. i) Subjective effects. ii) comparisons with toxicant exposure from tobacco smoke (using documented evidence) and with recommended safety limits

  6. E-cigarette puffing patterns associated with high and low nicotine e-liquid strength: effects on toxicant and carcinogen exposure

    Directory of Open Access Journals (Sweden)

    Sharon Cox

    2016-09-01

    Full Text Available Abstract Background Contrary to intuition, use of lower strength nicotine e-liquids might not offer reduced health risk if compensatory puffing behaviour occurs. Compensatory puffing (e.g. more frequent, longer puffs or user behaviour (increasing the wattage can lead to higher temperatures at which glycerine and propylene glycol (solvents used in e-liquids undergo decomposition to carbonyl compounds, including the carcinogens formaldehyde and acetaldehyde. This study aims to document puffing patterns and user behaviour associated with using high and low strength nicotine e-liquid and associated toxicant/carcinogen exposure in experienced e-cigarette users (known as vapers herein. Methods/design A counterbalanced repeated measures design. Participants: Non-tobacco smoking vapers; have used an e-cigarette for ≥3 months; currently using nicotine strength e-liquid ≥12mg/mL and a second or third generation device. Intervention: This study will measure puffing patterns in vapers whilst they use high and low strength nicotine e-liquid under fixed and user-defined settings, each for a week. The 4 counterbalanced conditions are: i low strength (6mg/mL, fixed settings; ii low strength user-defined settings; iii high strength (18mg/mL fixed settings; iv high strength user-defined settings. Biomarkers of exposure to toxicants and carcinogens will be measured in urine. In the second phase of this study, toxicant yields will be measured in aerosol generated using a smoking machine operated to replicate the puffing behaviours of each participant. Primary outcomes: i Puffing patterns (mean puff number, puff duration, inter-puff interval and mL of liquid consumed and user behaviour (changes to device settings: voltage and air-flow associated with using high and low strength nicotine e-liquid. ii Toxicant/carcinogen exposure associated with the puffing patterns/device settings used by our participants. Secondary outcomes: i Subjective effects. ii comparisons

  7. Developmental toxicity and molecular responses of marine medaka (Oryzias melastigma) embryos to ciguatoxin P-CTX-1 exposure.

    Science.gov (United States)

    Yan, Meng; Leung, Priscilla T Y; Ip, Jack C H; Cheng, Jin-Ping; Wu, Jia-Jun; Gu, Jia-Rui; Lam, Paul K S

    2017-04-01

    Ciguatoxins are produced by toxic benthic dinoflagellates and cause ciguatera fish poisoning worldwide, but the toxic effects on developing marine fish have not been well investigated. The Pacific ciguatoxin (P-CTX-1), is a potent sodium channel agonist, which is one of the most toxic members among all CTXs. This study evaluated the toxic effects of microinjecting purified Pacific ciguatoxin-1 (P-CTX-1) on embryonic development of marine medaka Oryzias melastigma. A lower 96h-LD 50 value was estimated for eleuthero-embryos (1.32ngg -1 ) than that for embryos (1.71ngg -1 ), indicating that P-CTX-1 is more lethal to newly hatched medaka larvae. P-CTX-1 induced detrimental effects during embryonic development, including hatching failure, abnormalities in physical development (caudal fin malformation and spinal deformities), internal damage (green coloration of the gall bladder and hemorrhaging), immune dysfunction, and altered muscle physiology (bradycardia and hyperkinetic twitching). The results of a transcriptional expression analysis of genes related to the stress/immune responses, cardiac and bone development, and apoptosis supported the observed developmental abnormalities. This study advanced the understanding of P-CTX-1 mediated toxic mechanisms in the development of early life stages of a fish, and thus contributed to the toxicity assessment of CTXs in marine ecosystems. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Bioavailability and toxicity of metals from a contaminated sediment by acid mine drainage: linking exposure-response relationships of the freshwater bivalve Corbicula fluminea to contaminated sediment.

    Science.gov (United States)

    Sarmiento, Aguasanta M; Bonnail, Estefanía; Nieto, José Miguel; DelValls, Ángel

    2016-11-01

    Streams and rivers strongly affected by acid mine drainage (AMD) have legal vacuum in terms of assessing the water toxicity, since the use of conventional environmental quality biomarkers is not possible due to the absence of macroinvertebrate organisms. The Asian clam Corbicula fluminea has been widely used as a biomonitor of metal contamination by AMD in freshwater systems. However, these clams are considered an invasive species in Spain and the transplantation in the field study is not allowed by the Environmental Protection Agency. To evaluate the use of the freshwater bivalve C. fluminea as a potential biomonitor for sediments contaminated by AMD, the metal bioavailability and toxicity were investigated in laboratory by exposure of clams to polluted sediments for 14 days. The studied sediments were classified as slightly contaminated with As, Cr, and Ni; moderately contaminated with Co; considerably contaminated with Pb; and heavily contaminated with Cd, Zn, and specially Cu, being reported as very toxic to Microtox. On the fourth day of the exposure, the clams exhibited an increase in concentration of Ga, Ba, Sb, and Bi (more than 100 %), followed by Co, Ni, and Pb (more than 60 %). After the fourth day, a decrease in concentration was observed for almost all metals studied except Ni. An allometric function was used to determine the relationship between the increases in metal concentration in soft tissue and the increasing bioavailable metal concentrations in sediments.

  9. Cytogenic Investigations in Flight Personnel

    International Nuclear Information System (INIS)

    Wolf, G.; Obe, G.; Bergau, L.

    1999-01-01

    During long-distance flights at high altitudes flight personnel are exposed to cosmic radiation. In order to determine whether there are biological effects of such low dose radiation exposure in aircrew, chromosomal aberrations were investigated in 59 female cabin attendants and a matched control group of 31 members of station personnel. The mean number of dicentric chromosomes amounts to 1.3 (95% CI 1.0-1.6) per 1,000 cells in cabin attendants and 1.4 (95% CI 1.0-1.9) per 1,000 cells in controls. In an additional control group of 56 female clerks from Berlin the mean frequency of dicentric chromosomes was 1.3 (95% CI 1.0-1.6). Neither in dicentric frequency and distribution nor in other aberrations was a significant difference between the groups of flight and station personnel found. The high frequency of multi-aberrant cells was remarkable in flight personnel as well as in station personnel. The reason for this phenomenon is unknown and needs further investigation. (author)

  10. Personnel monitoring system by thermoluminescence dosimeter - a study and review

    International Nuclear Information System (INIS)

    Iyer, V.S.; Alok, M.; Chandel, B.S.

    2018-01-01

    The principle objective of personnel monitoring system is to prevent overexposure and avoid unnecessary exposure of personnel working with various sources of radiation. The adequate system of personnel monitoring must provide for the measurement. evaluation and recording of significant doses accumulated by individuals together with a recording of conditions under which these doses are received

  11. Introducing Toxics

    Directory of Open Access Journals (Sweden)

    David C. Bellinger

    2013-04-01

    Full Text Available With this inaugural issue, Toxics begins its life as a peer-reviewed, open access journal focusing on all aspects of toxic chemicals. We are interested in publishing papers that present a wide range of perspectives on toxicants and naturally occurring toxins, including exposure, biomarkers, kinetics, biological effects, fate and transport, treatment, and remediation. Toxics differs from many other journals in the absence of a page or word limit on contributions, permitting authors to present their work in as much detail as they wish. Toxics will publish original research papers, conventional reviews, meta-analyses, short communications, theoretical papers, case reports, commentaries and policy perspectives, and book reviews (Book reviews will be solicited and should not be submitted without invitation. Toxins and toxicants concern individuals from a wide range of disciplines, and Toxics is interested in receiving papers that represent the full range of approaches applied to their study, including in vitro studies, studies that use experimental animal or non-animal models, studies of humans or other biological populations, and mathematical modeling. We are excited to get underway and look forward to working with authors in the scientific and medical communities and providing them with a novel venue for sharing their work. [...

  12. Paraquat and Maneb Exposure Alters Rat Neural Stem Cell Proliferation by Inducing Oxidative Stress: New Insights on Pesticide-Induced Neurodevelopmental Toxicity.

    Science.gov (United States)

    Colle, Dirleise; Farina, Marcelo; Ceccatelli, Sandra; Raciti, Marilena

    2018-06-01

    Pesticide exposure has been linked to the pathogenesis of neurodevelopmental and neurodegenerative disorders including autism spectrum disorders, attention deficit/hyperactivity, and Parkinson's disease (PD). Developmental exposure to pesticides, even at low concentrations not harmful for the adult brain, can lead to neuronal loss and functional deficits. It has been shown that prenatal or early postnatal exposure to the herbicide paraquat (PQ) and the fungicide maneb (MB), alone or in combination, causes permanent toxicity in the nigrostriatal dopamine system, supporting the idea that early exposure to these pesticides may contribute to the pathophysiology of PD. However, the mechanisms mediating PQ and MB developmental neurotoxicity are not yet understood. Therefore, we investigated the neurotoxic effect of low concentrations of PQ and MB in primary cultures of rat embryonic neural stem cells (NSCs), with particular focus on cell proliferation and oxidative stress. Exposure to PQ alone or in combination with MB (PQ + MB) led to a significant decrease in cell proliferation, while the cell death rate was not affected. Consistently, PQ + MB exposure altered the expression of major genes regulating the cell cycle, namely cyclin D1, cyclin D2, Rb1, and p19. Moreover, PQ and PQ + MB exposures increased the reactive oxygen species (ROS) production that could be neutralized upon N-acetylcysteine (NAC) treatment. Notably, in the presence of NAC, Rb1 expression was normalized and a normal cell proliferation pattern could be restored. These findings suggest that exposure to PQ + MB impairs NSCs proliferation by mechanisms involving alterations in the redox state.

  13. Environmental Exposure of Children to Toxic Trace Elements (Hg, Cr, As) in an Urban Area of Yucatan, Mexico: Water, Blood, and Urine Levels.

    Science.gov (United States)

    Arcega-Cabrera, F; Fargher, L; Quesadas-Rojas, M; Moo-Puc, R; Oceguera-Vargas, I; Noreña-Barroso, E; Yáñez-Estrada, L; Alvarado, J; González, L; Pérez-Herrera, N; Pérez-Medina, S

    2018-05-01

    Merida is the largest urban center in the Mexican State of Yucatan. Here domestic sewage is deposited in poorly built septic tanks and is not adequately treated. Because of contamination from such waste, water from the top 20 m of the aquifer is unsuitable for human consumption. Given this situation and because children are highly vulnerable to environmental pollution, including exposure to toxic trace elements, this study focused on evaluating the exposure of children to arsenic (As), chromium (Cr), and mercury (Hg) in water. It also evaluated the relationship between the levels of these elements in water and their concentrations in urine and blood. Among the 33 children monitored in the study, arsenic surpassed WHO limits for blood in 37% of the cases, which could result from the ingestion of poultry contaminated with organoarsenic compounds. In the case of WHO limits for Mercury, 65% of the water samples analyzed, 28% of urine samples, and 12% of blood samples exceeded them. Mercury exposure was correlated with biological sex, some lifestyle factors, and the zone in Merida in which children live. These data suggest that the levels of some toxic metals in children may be affected by water source, socioeconomic factors, and individual behavior.

  14. Bisphenol A accelerates toxic amyloid formation of human islet amyloid polypeptide: a possible link between bisphenol A exposure and type 2 diabetes.

    Directory of Open Access Journals (Sweden)

    Hao Gong

    Full Text Available Bisphenol A (BPA is a chemical compound widely used in manufacturing plastic products. Recent epidemiological studies suggest BPA exposure is positively associated with the incidence of type 2 diabetes mellitus (T2DM, however the mechanisms underlying this link remain unclear. Human islet amyloid polypeptide (hIAPP is a hormone synthesized and secreted by the pancreatic β-cells. Misfolding of hIAPP into toxic oligomers and mature fibrils can disrupt cell membrane and lead to β-cell death, which is regarded as one of the causative factors of T2DM. To test whether there are any connections between BPA exposure and hIAPP misfolding, we investigated the effects of BPA on hIAPP aggregation using thioflavin-T based fluorescence, transmission electronic microscopy, circular dichroism, dynamic light scattering, size-exclusion chromatography, fluorescence-dye leakage assay in an artificial micelle system and the generation of reactive oxygen species in INS-1 cells. We demonstrated that BPA not only dose-dependently promotes the aggregation of hIAPP and enhances the membrane disruption effects of hIAPP, but also promotes the extent of hIAPP aggregation related oxidative stress. Taken together, our results suggest that BPA exposure increased T2DM risk may involve the exacerbated toxic aggregation of hIAPP.

  15. Intravenous injection of unfunctionalized carbon-based nanomaterials confirms the minimal toxicity observed in aqueous and dietary exposures in juvenile rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Boyle, David; Sutton, Paul A; Handy, Richard D; Henry, Theodore B

    2018-01-01

    Numerous ecotoxicology studies of carbon-based nanomaterials (CNMs) have been conducted in fishes; however, different approaches have been used to make CNM dispersions and dose tanks for aqueous exposures, and to prepare food containing CNMs for dietary studies. This diversity of experimental methods has led to conflicting results and difficulties in comparing studies. The objective of the present study was to evaluate intravenous injection of unfunctionalized CNMs in rainbow trout (Oncorhynchus mykiss), as a means of delivering a known internal dose, on tissue biochemistry and histopathological lesions; then, subsequently, to compare the results with our previous work on aqueous and dietary exposures of rainbow trout to CNMs. Rainbow trout were injected in the caudal vein with corn oil dispersions of 200 μg (approximately 1 μg g -1 ) of either the fullerene C 60 , single-walled carbon nanotubes (SWCNTs), or amorphous carbon black. After 96 h, injected fish were euthanized and tissue samples collected for biochemistry and histology. Histological examination of the kidney of fish injected intravenously indicated the presence of black material consistent with the injected carbon treatments. However, there were no additional lesions associated with CNM exposure compared to controls. There were also no significant changes in haematology, or ionoregulatory disturbance in blood plasma among the intravenously injected fish. Significant elevation in lipid peroxidation (thiobarbituric acid reactive substances TBARS) was detected only in kidney and spleen of fish injected with SWCNTs, but not the other carbon treatments. The elevated TBARS following injection contrasted with CNMs delivered via aqueous or dietary routes in our previous studies, suggesting that the latter exposure routes may not lead to absorption and toxicity in the internal tissues. Comparison of the effects of injected CNMs with aqueous and dietary CNMs exposures indicates that these materials are of

  16. Modern methods of personnel dosimetry

    International Nuclear Information System (INIS)

    Kraus, W.; Herrmann, D.; Kiesewetter, W.

    The physical properties of radiation detectors for personnel dosimetry are described and compared. The suitability of different types of dosimeters for operational and central monitoring of normal occupational exposure, for accident and catastrophe dosimetry and for background and space-flight dosimetry is discussed. The difficulties in interpreting the dosimeter reading with respect to the dose in individual body organs are discussed briefly. 430 literature citations (up to Spring 1966) are given

  17. CAirTOX: A compartment model for assessing the fate of and human exposure to toxic-chemical emissions to air

    Energy Technology Data Exchange (ETDEWEB)

    McKone, T.E.

    1993-10-01

    CAirTOX has been developed as a spreadsheet model to assist in making a risk assessment of toxic air emissions. With CAirTOX, one can address how contaminants released to an air basin can lead to contamination of soil, food, surface water, and sediments. The modeling effort includes a multimedia transport and transformation model, exposure scenario models, and efforts to quantify uncertainty in multimedia, multiple-pathway exposure assessments. The multimedia transport and transformation model is a steady-state, but non-equilibrium model that can be used to assess concentrations of contaminants released continuously to air. In Part 1, the authors describe the multimedia transport and transformation model used to determine the fate of air emissions. In Part 2, they describe inputs and data needs for CAirTOX and the development of a set of landscape factors, which can be used to represent regional air basin/water-shed systems in California. In Part 3, they describe the multiple-pathway exposure scenarios and exposure algorithms. In Part 4, they compare the HRA approach and results and the CAirTOX exposure equations. In Part 5, they consider model sensitivity and uncertainty to determine how variability and uncertainty in model inputs affects the precision, accuracy, and credibility of the model output.

  18. A Decade of War: Prospective Trajectories of Posttraumatic Stress Disorder Symptoms Among Deployed US Military Personnel and the Influence of Combat Exposure (Publisher’s Version)

    Science.gov (United States)

    2017-09-27

    physical health (5) of service mem- bers. In addition, previous research indicates that exposure to combat may increase the likelihood of negative health ... physical , and behavioral health , studies have shown few negative effects of deployment with respect to posttraumatic stress disorder (PTSD) (10...American Journal of Epidemiology Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2017. This

  19. Fast algal eco-toxicity assessment: Influence of light intensity and exposure time on Chlorella vulgaris inhibition by atrazine and DCMU.

    Science.gov (United States)

    Camuel, Alexandre; Guieysse, Benoit; Alcántara, Cynthia; Béchet, Quentin

    2017-06-01

    In order to develop a rapid assay suitable for algal eco-toxicity assessments under conditions representative of natural ecosystems, this study evaluated the short-term (Chlorella vulgaris was exposed to these herbicides under 'standard' low light intensity (as prescribed by OECD201 guideline), the 20min-EC 50 values recorded via oxygen productivity (atrazine: 1.32±0.07μM; DCMU: 0.31±0.005μM) were similar the 96-h EC 50 recorded via algal growth (atrazine: 0.56μM; DCMU: 0.41μM), and within the range of values reported in the literature. 20min-EC50 values increased by factors of 3.0 and 2.1 for atrazine and DCMU, respectively, when light intensity increased from 60 to 1400μmolm -2 s -1 of photosynthetically active radiation, or PAR. Further investigation showed that exposure time significantly also impacted the sensitivity of C. vulgaris under high light intensity (>840μmolm -2 s -1 as PAR) as the EC 50 for atrazine and DCMU decreased by up to 6.2 and 2.1 folds, respectively, after 50min of exposure at a light irradiance of 1400μmolm -2 s -1 as PAR. This decrease was particularly marked at high light intensities and low algae concentrations and is explained by the herbicide disruption of the electron transfer chain triggering photo-inhibition at high light intensities. Eco-toxicity assessments aiming to understand the potential impact of toxic compounds on natural ecosystems should therefore be performed over sufficient exposure times (>20min for C. vulgaris) and under light intensities relevant to these ecosystems. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Availability of treatment resources for the management of acute toxic exposures and poisonings in emergency departments among various types of hospitals in Palestine: a cross-sectional study.

    Science.gov (United States)

    Zyoud, Sa'ed H; Al-Jabi, Samah W; Bali, Yara I; Al-Sayed, Afnan M; Sweileh, Waleed M; Awang, Rahmat

    2014-02-21

    Poisoning exposures continue to be a significant cause of morbidity and mortality worldwide. The lack of facilities, treatment resources, and antidotes in hospitals may affect the treatments provided and outcomes. This study aimed to determine the availability of gastrointestinal (GI) decontamination, stabilisation, elimination enhancement resources, and antidotes for the management of acute toxic exposures and poisonings in emergency departments (EDs) among various types of governmental and private hospitals in Palestine. A cross-sectional study using semi-structured questionnaire was performed. Data were collected based on hospital resources; GI decontamination, stabilisation, elimination enhancement resources and antidotes from Palestinian hospitals. Eighteen hospitals (94.7%) have responded. Among them, paracetamol poisoning was the most frequently reported cases by EDs (mean frequency score = 7.6 ± 2.1), followed by bee stings (mean = 6.9 ± 2.7) and organophosphate poisoning (mean = 6.7 ± 2.7). The availabilities of most resources related to GI decontamination items varied substantially with hospital type, but these differences were not statistical significant. The availability of stabilisation resources was not significantly different between hospitals types. For the availability of techniques used to enhance the elimination of toxic substances, there were variations between the hospitals types. However, these differences were not statistical significant, except for haemodialysis (p = 0.003) which was more available in governmental hospitals. For the availability of antidotes, none of the hospitals had sufficient stock of all antidotes listed. In relation to hospital type, there was variability in the availability of antidotes, but this did not reach statistical significance, except for deferoxamine (p management of acute toxic exposure and poisoning. The implementation of a minimum list of antidotes and treatment resources would be useful to increase the

  1. Physiologically based pharmacokinetic rat model for methyl tertiary-butyl ether; comparison of selected dose metrics following various MTBE exposure scenarios used for toxicity and carcinogenicity evaluation

    International Nuclear Information System (INIS)

    Borghoff, Susan J.; Parkinson, Horace; Leavens, Teresa L.

    2010-01-01

    There are a number of cancer and toxicity studies that have been carried out to assess hazard from methyl tertiary-butyl ether (MTBE) exposure via inhalation and oral administration. MTBE has been detected in surface as well as ground water supplies which emphasized the need to assess the risk from exposure via drinking water contamination. This model can now be used to evaluate route-to-route extrapolation issues concerning MTBE exposures but also as a means of comparing potential dose metrics that may provide insight to differences in biological responses observed in rats following different routes of MTBE exposure. Recently an updated rat physiologically based pharmacokinetic (PBPK) model was published that relied on a description of MTBE and its metabolite tertiary-butyl alcohol (TBA) binding to α2u-globulin, a male rat-specific protein. This model was used to predict concentrations of MTBE and TBA in the kidney, a target tissue in the male rat. The objective of this study was to use this model to evaluate the dosimetry of MTBE and TBA in rats following different exposure scenarios, used to evaluate the toxicity and carcinogenicity of MTBE, and compare various dose metrics under these different conditions. Model simulations suggested that although inhalation and drinking water exposures show a similar pattern of MTBE and TBA exposure in the blood and kidney (i.e. concentration-time profiles), the total blood and kidney levels following exposure of MTBE to 7.5 mg/ml MTBE in the drinking water for 90 days is in the same range as administration of an oral dose of 1000 mg/kg MTBE. Evaluation of the dose metrics also supports that a high oral bolus dose (i.e. 1000 mg/kg MTBE) results in a greater percentage of the dose exhaled as MTBE with a lower percent metabolized to TBA as compared to dose of MTBE that is delivered over a longer period of time as in the case of drinking water.

  2. Mercapturic acids: recent advances in their determination by liquid chromatography/mass spectrometry and their use in toxicant metabolism studies and in occupational and environmental exposure studies

    Science.gov (United States)

    Mathias, Patricia I.; B’Hymer, Clayton

    2016-01-01

    This review describes recent selected HPLC/MS methods for the determination of urinary mercapturates that are useful as non-invasive biomarkers in characterizing human exposure to electrophilic industrial chemicals in occupational and environmental studies. High performance liquid chromatography/mass spectrometry is a sensitive and specific method for analysis of small molecules found in biological fluids. In this review, recent selected mercapturate quantification methods are summarized and specific cases are presented. The biological formation of mercapturates is introduced and their use indicators of metabolic processing of reactive toxicants is discussed, as well as future trends and limitations in this area of research. PMID:26900903

  3. Neutron personnel dosimetry

    International Nuclear Information System (INIS)

    Griffith, R.V.

    1981-01-01

    The current state-of-the-art in neutron personnel dosimetry is reviewed. Topics covered include dosimetry needs and alternatives, current dosimetry approaches, personnel monitoring devices, calibration strategies, and future developments

  4. Personnel Monitoring Department - DEMIN

    International Nuclear Information System (INIS)

    1989-01-01

    The activities and purposes of the Personnel Monitoring Dept. of the Institute of Radioprotection and Dosimetry of the Brazilian CNEN are presented. A summary of the personnel monitoring service is given, such as dosemeters supply, laboratorial inspections, and so on. The programs of working, publishing, courses and personnel interchange are also presented. (J.A.M.M.)

  5. Deciphering mechanisms of malathion toxicity under pulse exposure of the freshwater cladoceran Daphnia magna

    DEFF Research Database (Denmark)

    Trác, Ngoc Lâm; Andersen, Ole; Palmqvist, Annemette

    2016-01-01

    ; enzyme activities of acetylcholinesterase (AChE), carboxylesterase (CbE), and glutathione S-transferase (GST); and AChE gene expression. The results showed no difference in survival among equivalent integrated doses. Adverse sublethal effects were driven by exposure concentration rather than pulse...... duration. Specifically, short pulse exposure to a high concentration of malathion resulted in more immobilized daphnids, lower AChE and CbE activities, and a higher transcript level ofAChE gene compared with long pulse exposure to low concentration. The expression of the AChE gene was up...

  6. School Personnel Responses to Children Exposed to Violence

    Science.gov (United States)

    Kenemore, Thomas; Lynch, John; Mann, Kimberly; Steinhaus, Patricia; Thompson, Theodore

    2010-01-01

    Authors explored the experiences of school personnel in their responses to children's exposure to violence. Thirty-one school personnel, including administrators, teachers, counselors, school social workers, and psychologists, were interviewed to obtain data on their experiences related to violence exposure in their schools and the surrounding…

  7. Radiation exposure to personnel involved in bone scans for horses with technetium 99m-diphosphonat; Strahlenexposition des Personals bei der Skelettszintigrafie mit Technetium-99m-Diphosphonat beim Pferd

    Energy Technology Data Exchange (ETDEWEB)

    Sommerfeld, Theresa Christine

    2016-07-01

    Key objective of this study has been the evaluation of radiation exposure of veterinarian personnel wearing dosimeters which were involved in equine scintigraphy. A survey, which was developed in parallel to this study, showed that personnel in equine horse clinics have often knowledge gaps about scintigraphy and the related radiation doses. The survey showed skepticism of the involved personnel towards the methods of bone scintigraphy as the impacts of expositions are barely known in common. The scintigraphic investigations and measurements were done at the horse clinic (department of surgery) in Giessen and were part of the routinely bone scanning of horses. A total of 33 bone scans were taken, covering either full- or half-body scintigraphies. Additional 10 bone scans covered measurements with and without the protection of a 0,5 mm lead-shield. The activity of involved personnel was monitored at four different positions: MP1 was associated with the position of the person preparing the radiopharmaceutical for injection, MP2 with the position at holding the horse during the bone scan, MP3 with the position at holding the horse's legs and to make sure that the horse was standing in the right position, MP4 with the position for the camera operator. Some more dose measurements were made from the horse body (MP5 and MP6) as well as in the control area (MP7). In order to analyze the patient's constitution, additional data like weight, size, body extent and length of the torso were additionally captured. The body data were collected to investigate exposure differences of rather big and heavy or small and thin horses. These data and the dosimeter at the horse body (MP5) enabled the correlation analysis between the horse body composition and the received dose rate of the personnel (MP2). MP1 received a mean dose of 11 μSv and a dose rate of 123 μSv/h, MP2 received 31 μSv for a whole-body and 23 μSv for a half-body bone scan. The dose rate of MP2 was 22

  8. Personnel preferences in personnel planning and scheduling

    OpenAIRE

    van der Veen, Egbert

    2013-01-01

    Summary The personnel of an organization often has two conflicting goals. Individual employees like to have a good work-life balance, by having personal preferences taken into account, whereas there is also the common goal to work efficiently. By applying techniques and methods from Operations Research, a subfield of applied mathematics, we show that operational efficiency can be achieved while taking personnel preferences into account. In the design of optimization methods, we explicitly con...

  9. Response of DNA, proteins, lipids and antioxidant enzymes as measure of toxicity to mercury exposures in green mussel Perna viridis

    Digital Repository Service at National Institute of Oceanography (India)

    Verlecar, X.N.; Jena, K.B.; Chainy, G.B.N.

    Studies on exposures of gills of green-lipped mussel Perna viridis to sublethal levels of mercury (Hg) indicates that oxidative stress marker like lipids peroxidation and protein carbonyl content increase. With the exception of superoxide dismutase...

  10. Linking high resolution mass spectrometry data with exposure and toxicity forecasts to advance high-throughput environmental monitoring

    Data.gov (United States)

    U.S. Environmental Protection Agency — There is a growing need in the field of exposure science for monitoring methods that rapidly screen environmental media for suspect contaminants. Measurement and...

  11. Short- and Long-Term Effects of Prenatal Exposure to Iron Oxide Nanoparticles: Influence of Surface Charge and Dose on Developmental and Reproductive Toxicity

    Directory of Open Access Journals (Sweden)

    Kristin R. Di Bona

    2015-12-01

    Full Text Available Iron oxide nanoparticles (NPs are commonly utilized for biomedical, industrial, and commercial applications due to their unique properties and potential biocompatibility. However, little is known about how exposure to iron oxide NPs may affect susceptible populations such as pregnant women and developing fetuses. To examine the influence of NP surface-charge and dose on the developmental toxicity of iron oxide NPs, Crl:CD1(ICR (CD-1 mice were exposed to a single, low (10 mg/kg or high (100 mg/kg dose of positively-charged polyethyleneimine-Fe2O3-NPs (PEI-NPs, or negatively-charged poly(acrylic acid-Fe2O3-NPs (PAA-NPs during critical windows of organogenesis (gestation day (GD 8, 9, or 10. A low dose of NPs, regardless of charge, did not induce toxicity. However, a high exposure led to charge-dependent fetal loss as well as morphological alterations of the uteri (both charges and testes (positive only of surviving offspring. Positively-charged PEI-NPs given later in organogenesis resulted in a combination of short-term fetal loss (42% and long-term alterations in reproduction, including increased fetal loss for second generation matings (mice exposed in utero. Alternatively, negatively-charged PAA-NPs induced fetal loss (22% earlier in organogenesis to a lesser degree than PEI-NPs with only mild alterations in offspring uterine histology observed in the long-term.

  12. Exposure to Inorganic Nanoparticles: Routes of Entry, Immune Response, Biodistribution and In Vitro/In Vivo Toxicity Evaluation

    Directory of Open Access Journals (Sweden)

    Valeria De Matteis

    2017-10-01

    Full Text Available The development of different kinds of nanoparticles, showing different physico-chemical properties, has fostered their large use in many fields, including medicine. As a consequence, inorganic nanoparticles (e.g., metals or semiconductors, have raised issues about their potential toxicity. The scientific community is investigating the toxicity mechanisms of these materials, in vitro and in vivo, in order to provide accurate references concerning their use. This review will give the readers a thorough exploration on the entry mechanisms of inorganic nanoparticles in the human body, such as titanium dioxide nanoparticles (TiO2NPs, silicon dioxide nanoparticles (SiO2NPs, zinc oxide nanoparticles (ZnONPs, silver nanoparticles (AgNPs, gold nanoparticles (AuNPs and quantum dots (QDsNPs. In addition, biodistribution, the current trends and novelties of in vitro and in vivo toxicology studies will be discussed, with a particular focus on immune response.

  13. Acetylated H4K16 by MYST1 protects UROtsa cells from arsenic toxicity and is decreased following chronic arsenic exposure

    International Nuclear Information System (INIS)

    Jo, William Jaime; Ren, Xuefeng; Chu, Feixia; Aleshin, Maria; Wintz, Henri; Burlingame, Alma; Smith, Martyn Thomas; Vulpe, Chris Dillon; Zhang Luoping

    2009-01-01

    Arsenic, a human carcinogen that is associated with an increased risk of bladder cancer, is commonly found in drinking water. An important mechanism by which arsenic is thought to be carcinogenic is through the induction of epigenetic changes that lead to aberrant gene expression. Previously, we reported that the SAS2 gene is required for optimal growth of yeast in the presence of arsenite (As III ). Yeast Sas2p is orthologous to human MYST1, a histone 4 lysine 16 (H4K16) acetyltransferase. Here, we show that H4K16 acetylation is necessary for the resistance of yeast to As III through the modulation of chromatin state. We further explored the role of MYST1 and H4K16 acetylation in arsenic toxicity and carcinogenesis in human bladder epithelial cells. The expression of MYST1 was knocked down in UROtsa cells, a model of bladder epithelium that has been used to study arsenic-induced carcinogenesis. Silencing of MYST1 reduced acetylation of H4K16 and induced sensitivity to As III and to its more toxic metabolite monomethylarsonous acid (MMA III ) at doses relevant to high environmental human exposures. In addition, both As III and MMA III treatments decreased global H4K16 acetylation levels in a dose- and time-dependent manner. This indicates that acetylated H4K16 is required for resistance to arsenic and that a reduction in its levels as a consequence of arsenic exposure may contribute to toxicity in UROtsa cells. Based on these findings, we propose a novel role for the MYST1 gene in human sensitivity to arsenic.

  14. Recent research on Gulf War illness and other health problems in veterans of the 1991 Gulf War: Effects of toxicant exposures during deployment.

    Science.gov (United States)

    White, Roberta F; Steele, Lea; O'Callaghan, James P; Sullivan, Kimberly; Binns, James H; Golomb, Beatrice A; Bloom, Floyd E; Bunker, James A; Crawford, Fiona; Graves, Joel C; Hardie, Anthony; Klimas, Nancy; Knox, Marguerite; Meggs, William J; Melling, Jack; Philbert, Martin A; Grashow, Rachel

    2016-01-01

    Veterans of Operation Desert Storm/Desert Shield - the 1991 Gulf War (GW) - are a unique population who returned from theater with multiple health complaints and disorders. Studies in the U.S. and elsewhere have consistently concluded that approximately 25-32% of this population suffers from a disorder characterized by symptoms that vary somewhat among individuals and include fatigue, headaches, cognitive dysfunction, musculoskeletal pain, and respiratory, gastrointestinal and dermatologic complaints. Gulf War illness (GWI) is the term used to describe this disorder. In addition, brain cancer occurs at increased rates in subgroups of GW veterans, as do neuropsychological and brain imaging abnormalities. Chemical exposures have become the focus of etiologic GWI research because nervous system symptoms are prominent and many neurotoxicants were present in theater, including organophosphates (OPs), carbamates, and other pesticides; sarin/cyclosarin nerve agents, and pyridostigmine bromide (PB) medications used as prophylaxis against chemical warfare attacks. Psychiatric etiologies have been ruled out. This paper reviews the recent literature on the health of 1991 GW veterans, focusing particularly on the central nervous system and on effects of toxicant exposures. In addition, it emphasizes research published since 2008, following on an exhaustive review that was published in that year that summarizes the prior literature (RACGWI, 2008). We conclude that exposure to pesticides and/or to PB are causally associated with GWI and the neurological dysfunction in GW veterans. Exposure to sarin and cyclosarin and to oil well fire emissions are also associated with neurologically based health effects, though their contribution to development of the disorder known as GWI is less clear. Gene-environment interactions are likely to have contributed to development of GWI in deployed veterans. The health consequences of chemical exposures in the GW and other conflicts have been

  15. Toxicity and carcinogenicity of methyl isobutyl ketone in F344N rats and B6C3F1 mice following 2-year inhalation exposure

    International Nuclear Information System (INIS)

    Stout, Matthew D.; Herbert, Ronald A.; Kissling, Grace E.; Suarez, Fernando; Roycroft, Joseph H.; Chhabra, Rajendra S.; Bucher, John R.

    2008-01-01

    Methyl isobutyl ketone (MIBK) is primarily used as a denaturant for rubbing alcohol, as a solvent and in the manufacture of methyl amyl alcohol. Inhalation of vapors is the most likely route of exposure in the work place. In order to evaluate the potential of MIBK to induce toxic and carcinogenic effects following chronic exposure, groups of 50 male and 50 female F344/N rats and B6C3F1 mice were exposed to MIBK at concentrations of 0, 450, 900, or 1800 ppm by inhalation, 6 h/day, 5 days per week for 2 years. Survival was decreased in male rats at 1800 ppm. Body weight gains were decreased in male rats at 900 and 1800 ppm and in female mice at 1800 ppm. The primary targets of MIBK toxicity and carcinogenicity were the kidney in rats and the liver in mice. In male rats, there was increased mineralization of the renal papilla at all exposure concentrations. The incidence of chronic progressive nephropathy (CPN) was increased at 1800 ppm and the severity was increased in all exposed groups. There were also increases in renal tubule hyperplasia at all exposure concentrations, and in adenoma and adenoma or carcinoma (combined) at 1800 ppm; these lesions are thought to represent a continuum in the progression of proliferative lesions in renal tubule epithelium. These increases may have resulted from the increased severity of CPN, either through α2μ-globulin-dependent or -independent mechanisms. An increase in mononuclear cell leukemia at 1800 ppm was an uncertain finding. Adrenal medulla hyperplasia was increased at 1800 ppm, and there was a positive trend for increases in benign or malignant pheochromocytomas (combined). In female rats, there were increases in the incidence of CPN in all exposure concentrations and in the severity at 1800 ppm, indicating that CPN was increased by mechanisms in addition to those related to α2μ-globulin. There were renal mesenchymal tumors, which have not been observed in historical control animals, in two female rats at 1800 ppm. The

  16. Evaluation of Pulmonary and Systemic Toxicity of Oil Dispersant (COREXIT EC9500A(®)) Following Acute Repeated Inhalation Exposure.

    Science.gov (United States)

    Roberts, Jenny R; Anderson, Stacey E; Kan, Hong; Krajnak, Kristine; Thompson, Janet A; Kenyon, Allison; Goldsmith, William T; McKinney, Walter; Frazer, David G; Jackson, Mark; Fedan, Jeffrey S

    2014-01-01

    Oil spill cleanup workers come into contact with numerous potentially hazardous chemicals derived from the oil spills, as well as chemicals applied for mitigation of the spill, including oil dispersants. In response to the Deepwater Horizon Macondo well oil spill in the Gulf of Mexico in 2010, a record volume of the oil dispersant, COREXIT EC9500A, was delivered via aerial applications, raising concern regarding potential health effects that may result from pulmonary exposure to the dispersant. The current study examined the effects on pulmonary functions, cardiovascular functions, and systemic immune responses in rats to acute repeated inhalation exposure of COREXIT EC9500A at 25 mg/m(3), five hours per day, over nine work days, or filtered air (control). At one and seven days following the last exposure, a battery of parameters was measured to evaluate lung function, injury, and inflammation; cardiovascular function; peripheral vascular responses; and systemic immune responses. No significant alterations in airway reactivity were observed at one or seven days after exposure either in baseline values or following methacholine (MCh) inhalation challenge. Although there was a trend for an increase in lung neutrophils and phagocyte oxidant production at one-day post exposure, there were no significant differences in parameters of lung inflammation. In addition, increased blood monocytes and neutrophils, and decreased lymphocyte numbers at one-day post exposure also did not differ significantly from air controls, and no alterations in splenocyte populations, or serum or spleen immunoglobulin M (IgM) to antigen were observed. There were no significant differences in peripheral vascular responsiveness to vasoconstrictor and vasodilator agonists or in blood pressure (BP) responses to these agents; however, the baseline heart rate (HR) and HR responses to isoproterenol (ISO) were significantly elevated at one-day post exposure, with resolution by day 7. In summary, acute

  17. Evaluation of Pulmonary and Systemic Toxicity of Oil Dispersant (COREXIT EC9500A following Acute Repeated Inhalation Exposure

    Directory of Open Access Journals (Sweden)

    Jenny R. Roberts

    2014-01-01

    Full Text Available Introduction Oil spill cleanup workers come into contact with numerous potentially hazardous chemicals derived from the oil spills, as well as chemicals applied for mitigation of the spill, including oil dispersants. In response to the Deepwater Horizon Macondo well oil spill in the Gulf of Mexico in 2010, a record volume of the oil dispersant, COREXIT EC9500A, was delivered via aerial applications, raising concern regarding potential health effects that may result from pulmonary exposure to the dispersant. Methods The current study examined the effects on pulmonary functions, cardiovascular functions, and systemic immune responses in rats to acute repeated inhalation exposure of COREXIT EC9500A at 25 mg/m 3 , five hours per day, over nine work days, or filtered air (control. At one and seven days following the last exposure, a battery of parameters was measured to evaluate lung function, injury, and inflammation; cardiovascular function; peripheral vascular responses; and systemic immune responses. Results No significant alterations in airway reactivity were observed at one or seven days after exposure either in baseline values or following metha-choline (MCh inhalation challenge. Although there was a trend for an increase in lung neutrophils and phagocyte oxidant production at one-day post exposure, there were no significant differences in parameters of lung inflammation. In addition, increased blood monocytes and neutrophils, and decreased lymphocyte numbers at one-day post exposure also did not differ significantly from air controls, and no alterations in splenocyte populations, or serum or spleen immunoglobulin M (IgM to antigen were observed. There were no significant differences in peripheral vascular responsiveness to vasoconstrictor and vasodilator agonists or in blood pressure (BP responses to these agents; however, the baseline heart rate (HR and HR responses to isoproterenol (ISO were significantly elevated at one-day post exposure

  18. Neutron personnel dosimetry

    International Nuclear Information System (INIS)

    Griffith, R.V.

    1982-01-01

    The measurement of neutron exposures to personnel is an issue that has received increased attention in the last few years. It is important to consider key aspects of the whole dosimetry system when developing dose estimates. This begins with selection of proper dosimeters and survey instruments, and extends through the calibration methods. One must match the spectral response and sensitivity of the dosimeter to the spectral characteristics of the neutron fields. Threshold detectors that are insensitive to large fractions of neutrons in the lower energy portion of reactor spectra should be avoided. Use of two or more detectors with responses that complement each other will improve measurement quality. It is important to understand the spectral response of survey instruments, so that spectra which result in significant overresponse do not lead to overestimation of dose. Calibration sources that do not match operational field spectra can contribute to highly erroneous results. In those situations, in-field calibration techniques should be employed. Although some detection developments have been made in recent years, a lot can be done with existing technology until fully satisfactory, long term solutions are obtained

  19. Toxic substances alert program

    Science.gov (United States)

    Junod, T. L.

    1978-01-01

    A toxicity profile is provided, of 187 toxic substances procured by NASA Lewis Research Center during a 3 1/2 year period, including 27 known or suspected carcinogens. The goal of the program is to assure that the center's health and safety personnel are aware of the procurement and use of toxic substances and to alert and inform the users of these materials as to the toxic characteristics and the control measures needed to ensure their safe use. The program also provides a continuing record of the toxic substances procured, who procured them, what other toxic substances the user has obtained in the past, and where similar materials have been used elsewhere at the center.

  20. Toxicity of chromium (VI) to two mussels and an amphipod in water-only exposures with or without a co-stressor of elevated temperature, zinc, or nitrate

    Science.gov (United States)

    Wang, Ning; Kunz, James L.; Ivey, Chris D.; Ingersoll, Christopher G.; Barnhart, M. Christopher; Glidewell, Elizabeth A.

    2017-01-01

    The objectives of the present study were to develop methods for propagating western pearlshell (Margaritifera falcata) for laboratory toxicity testing and evaluate acute and chronic toxicity of chromium VI [Cr(VI)] to the pearlshell and a commonly tested mussel (fatmucket, Lampsilis siliquoidea at 20 °C or in association with a co-stressor of elevated temperature (27 °C), zinc (50 µg Zn/L), or nitrate (35 mg NO3/L). A commonly tested invertebrate (amphipod, Hyalella azteca) also was tested in chronic exposures. Newly transformed pearlshell (~1 week old) were successfully cultured and tested in acute 96 h Cr exposures (control survival 100%). However, the grow-out of juveniles in culture for chronic toxicity testing was less successful and chronic 28-day Cr toxicity tests started with 4 month-old pearlshell failed due to low control survival (39–68%). Acute median effect concentration (EC50) for the pearlshell (919 µg Cr/L) and fatmucket (456 µg Cr/L) tested at 20 °C without a co-stressor decreased by a factor of > 2 at elevated temperature but did not decrease at elevated Zn or elevated NO3. Chronic 28-day Cr tests were completed successfully with the fatmucket and amphipod (control survival 83–98%). Chronic maximum acceptable toxicant concentration (MATC) for fatmucket at 20 °C (26 µg Cr/L) decreased by a factor of 2 at elevated temperature or NO3 but did not decrease at elevated Zn. However, chronic MATC for amphipod at 20 °C (13 µg Cr/L) did not decrease at elevated temperature, Zn, or NO3. Acute EC50s for both mussels tested with or without a co-stressor were above the final acute value used to derive United States Environmental Protection Agency acute water quality criterion (WQC) for Cr(VI); however, chronic MATCs for fatmucket at elevated temperature or NO3 and chronic MATCs for the amphipod at 20 °C with or without elevated Zn or NO3 were about equal to the chronic WQC. The results indicate that (1) the elevated temperature

  1. Assessment of lung cell toxicity of various gasoline engine exhausts using a versatile in vitro exposure system.

    Science.gov (United States)

    Bisig, Christoph; Comte, Pierre; Güdel, Martin; Czerwinski, Jan; Mayer, Andreas; Müller, Loretta; Petri-Fink, Alke; Rothen-Rutishauser, Barbara

    2018-04-01

    Adverse effect studies of gasoline exhaust are scarce, even though gasoline direct injection (GDI) vehicles can emit a high number of particles. The aim of this study was to conduct an in vitro hazard assessment of different GDI exhausts using two different cell culture models mimicking the human airway. In addition to gasoline particle filters (GPF), the effects of two lubrication oils with low and high ash content were assessed, since it is known that oils are important contributors to exhaust emissions. Complete exhausts from two gasoline driven cars (GDI1 and GDI2) were applied for 6 h (acute exposure) to a multi-cellular human lung model (16HBE14o-cell line, macrophages, and dendritic cells) and a primary human airway model (MucilAir™). GDI1 vehicle was driven unfiltered and filtered with an uncoated and a coated GPF. GDI2 vehicle was driven under four settings with different fuels: normal unleaded gasoline, 2% high and low ash oil in gasoline, and 2% high ash oil in gasoline with a GPF. GDI1 unfiltered was also used for a repeated exposure (3 times 6 h) to assess possible adverse effects. After 6 h exposure, no genes or proteins for oxidative stress or pro-inflammation were upregulated compared to the filtered air control in both cell systems, neither in GDI1 with GPFs nor in GDI2 with the different fuels. However, the repeated exposure led to a significant increase in HMOX1 and TNFa gene expression in the multi-cellular model, showing the responsiveness of the system towards gasoline engine exhaust upon prolonged exposure. The reduction of particles by GPFs is significant and no adverse effects were observed in vitro during a short-term exposure. On the other hand, more data comparing different lubrication oils and their possible adverse effects are needed. Future experiments also should, as shown here, focus on repeated exposures. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Vitamin C attenuates biochemical and genotoxic damage in common carp (Cyprinus carpio) upon joint exposure to combined toxic doses of fipronil and buprofezin insecticides.

    Science.gov (United States)

    Ghazanfar, Madiha; Shahid, Sana; Qureshi, Irfan Zia

    2018-03-01

    In the present study, potential protective role of Vitamin C (l-ascorbic acid) was investigated in aquaria acclimated common carp (Cyprinus carpio) following exposure for 96 h to combined toxic doses of fipronil (FP) and buprofezin (BPFN) insecticides in combination (FP: 200 μg/L; 4.57 × 10 -7  mol/L and BPFN: 50 mg/L; 1.64 × 10 -4  mol/L). At end of 96 h exposure, fish were supplemented with low (25 mg/L) and high (50 mg/L) doses of Vitamin C, added once daily to aquaria water for continuous three weeks. Appropriate control groups were run in parallel. Fish behavior was monitored throughout for signs of toxicity. At completion of experiments, liver, kidney, brain and gills were excised for toxicity assessment and possible remediation by the Vitamin C through biochemical determination of reactive oxygen species (ROS), thiobarbituric acid reactive substances or TBARS, reduced glutathione (GSH) and total protein content, levels of catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD), and the Comet assay. Hepatosomatic index (HSI), condition factor (CF), survival rate (SR), and combination index (CI) were also determined. Data were compared statistically at p < 0.05. Results showed significant behavioral and biochemical alterations, and DNA damage in the fish group exposed to FP and BPFN in combination. In fish groups supplemented with Vitamin C following FP and BPFN treatment, significant alleviation in tissue damage and toxic effects was represented by substantial decreases in ROS and TBARS production (p < 0.001), along with a concomitant significant increase in the survival rate, GSH and total protein content, HSI, CF, and activities of SOD, CAT and POD enzymes (p < 0.001). Mean tail length of comet and percent tail DNA decreased significantly (p < 0.001), which indicated amelioration of DNA damage. The study concludes that Vitamin C is an effective remedial treatment against FP and BPFN-induced damage in

  3. Novel route of toxicant exposure in an ancient extant vertebrate: nickel uptake by hagfish skin and the modifying effects of slime.

    Science.gov (United States)

    Glover, Chris N; Blewett, Tamzin A; Wood, Chris M

    2015-02-03

    Utilizing an in vitro technique, the skin of Pacific hagfish (Eptatretus stouti) was shown to take up nickel from the water via a high affinity, low capacity transport pathway. Uptake was biphasic, with saturation occurring at low nickel exposure concentrations, superseded by linear, diffusive uptake at levels greater than 50 μM. In vivo exposures showed that nickel accumulated mainly in the gill, heart, and brain, representing a tissue distribution distinct from that found in teleosts. Slime on the epidermal surface was shown to significantly reduce the uptake of low concentrations (10 μM) of the metals zinc and nickel, but slime had no effect on organic nutrient (the amino acid l-alanine) absorption. At a higher metal exposure concentration (1 mM), slime was no longer protective, indicating saturation of metal-binding sites. This is the first study to show that metals can be taken up by the integument of hagfish. The ability of the skin to act as a transport epithelium may be of particular importance for a burrowing, benthic scavenger, such as hagfish, which are likely to be exposed to relatively enriched levels of metal toxicants through their habitat and lifestyle, and this may have consequences for human health through hagfish consumption.

  4. Impact of Indocyanine Green Concentration, Exposure Time, and Degree of Dissolution in Creating Toxic Anterior Segment Syndrome: Evaluation in a Rabbit Model

    Directory of Open Access Journals (Sweden)

    Tamer Tandogan

    2016-01-01

    Full Text Available Purpose. To investigate the role of indocyanine green (ICG dye as a causative material of toxic anterior segment syndrome (TASS in an experimental rabbit model. Method. Eight eyes of four rabbits were allocated to this study. Capsular staining was performed using ICG dye, after which the anterior chamber was irrigated with a balanced salt solution. The effects of different concentrations (control, 0.25, 0.5, and 1.0%, exposure times (10 and 60 seconds, and the degree of dissolution (differently vortexed were investigated. The analysis involved anterior segment photography, ultrasound pachymetry, prostaglandin assay (PGE2 Parameter Assay, R&D systems, Inc., and scanning electron microscopy of each iris. Result. There was no reaction in the control eye. A higher aqueous level of PGE2 and more severe inflammatory reaction were observed in cases of eyes with higher concentration, longer exposure time, and poorly dissolved dye. Additionally, scanning electron microscopy revealed larger and coarser ICG particles. Conclusion. TASS occurrence may be associated with the concentration, exposure time, and degree of dissolution of ICG dye during cataract surgery.

  5. Subchronic 13-week inhalation exposure of rats to multiwalled carbon nanotubes: toxic effects are determined by density of agglomerate structures, not fibrillar structures.

    Science.gov (United States)

    Pauluhn, Jürgen

    2010-01-01

    Wistar rats were nose-only exposed to multiwalled carbon nanotubes (MWCNT, Baytubes) in a subchronic 13-week inhalation study. The focus of study was on respiratory tract and systemic toxicity, including analysis of MWCNT biokinetics in the lungs and lung-associated lymph nodes (LALNs). The time course and concentration dependence of pulmonary effects were examined by bronchoalveolar lavage (BAL) and histopathology up to 6 months postexposure. Particular emphasis was directed to the comparative characterization of MWCNT structures prior to and after micronization and dry powder dispersion into inhalation chambers. These determinations were complemented by additional analyses in digested BAL cells. Animals were exposed on 6 h/day, 5 days per week for 13 consecutive weeks to 0, 0.1, 0.4, 1.5, and 6 mg/m(3). The subchronic exposure to respirable solid aerosols of MWCNT was tolerated without effects suggestive of systemic toxicity. Kinetic analyses demonstrated a markedly delayed clearance of MWCNT from lungs at overload conditions. Translocation into LALNs occurred at 1.5 and 6 mg/m(3) and required at least 13 weeks of study to become detectable. At these exposure levels, the lung and LALN weights were significantly increased. Sustained elevations in BAL polymorphonuclear neutrophils and soluble collagen occurred at these concentrations with borderline effects at 0.4 mg/m(3). Histopathology revealed principal exposure-related lesions at 0.4 mg/m(3) and above in the upper respiratory tract (goblet cell hyper- and/or metaplasia, eosinophilic globules, and focal turbinate remodeling) and the lower respiratory tract (inflammatory changes in the bronchioloalveolar region and increased interstitial collagen staining). Granulomatous changes and a time-dependent increase of a bronchioloalveolar hyperplasia occurred at 6 mg/m(3). All end points examined were unremarkable at 0.1 mg/m(3) (no-observed-adverse-effect-level). In summary, this study demonstrates that the induced

  6. Molecular and cellular determinants of the cyto-toxicity in combined ionizing radiations and anti-tumoral drugs exposure

    International Nuclear Information System (INIS)

    Hennequin, Ch.

    1998-01-01

    The radio-chemo-therapy combinations represent a major research way in oncology. The knowledge of the interaction mechanisms can contribute to an improvement of the clinical protocols and to a knowledge of the action processes of drugs and radiations. Three different drugs have been studied - etoposide, camptothecine and taxoids (paclitaxel, docetaxel) - on different in vitro cell descendants (V79, HeLa and SQ-20B). For etoposide, the isobolic analysis shows an additive interaction in slightly deferred exposure but a strong supra-additive interaction in concomitant exposure. A sensitization to the drug effect inside the radio-induced G2 block is also noticed. The supra-additivity in concomitant exposure is linked with the alteration of the sub-lethal lesions repair. For camptothecine, the analysis of survival curves shows a strictly additive interaction (mode II) in concomitant exposure. However, the association becomes additive at low radiation dose rates (1 Gy/h). This synergy is the result of a cyto-kinetic effect corresponding to the radio-induced accumulation of cells inside the most drug sensible compartment. With taxoids, it is shown that all kinds of interactions are possible, from a pronounced antagonism to a significant synergy. The effect depends on drugs and radiation doses and on the cells descendants. Paclitaxel and docetaxel present major differences of phase specif