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# Extrapolation of dosimetric relationships for inhaled particles and gases by Symposium on Extrapolation Modeling of Inhaled Particles and Gases: Lung Dosimetry (1987 Duke University Medical Center)

Written in English

## Subjects:

• Aerosols -- Toxicity testing -- Congresses.,
• Toxicology, Experimental -- Congresses.,
• Chemical dosimetry -- Congresses.,
• Toxicology -- Animal models -- Congresses.,
• Air -- Pollution -- Research -- Methodology -- Congresses.

Edition Notes

## Book details

Classifications The Physical Object Statement edited by James D. Crapo ... [et al.]. Contributions Crapo, James D., Duke University. Center for Extrapolation Modeling. LC Classifications RA1270.A34 S96 1987 Pagination xiv, 377 p. : Number of Pages 377 Open Library OL2056329M ISBN 10 0121967808 LC Control Number 88034696

Extrapolation of dosimetric relationships for inhaled particles and gases. San Diego: Academic Press, © (OCoLC) Online version: Symposium on Extrapolation Modeling of Inhaled Particles and Gases: Lung Dosimetry ( Duke University Medical Center).

Extrapolation of dosimetric relationships for inhaled particles and gases. @article{osti_, title = {Extrapolation of domestic relationships for inhaled particles and gases}, author = {Crapo, J D and Smolko, E D and Miller, F J and Graham, J A and Hayes, A W}, abstractNote = {The environmental pollutants to which humans are exposed are rapidly increasing in terms of number, complexity, and concentration.

One of the great challenges in environmental. adshelp[at] The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86AAuthor: James H.

Vincent. Several extensive reviews are available for dosimetry modeling of inhaled particles (4)(5) (6) (7)(8)(9) and gas uptake. (4,5,(10)(11)(12)(13)(14)(15)(16) The degree of detail or sophistication in. Abstract Direct calculation of delivered dose in the species of interest potentially affects the magnitude of an uncertainty factor needed to address extrapolation of laboratory animal data to equivalent human exposure scenarios, thereby improving the accuracy of human health risk estimates.

Development of an inhalation reference concentration (RfC) typically involves extrapolation of an. Extrapolation of Dosimetric Relationships for Inhaled Particles and Gases by JD, Ed Crapo () 3 editions published in in English and held by 3 WorldCat member libraries worldwide.

inhaled particles and gases are provided in this section. cancer dose-response relationship. A recent evaluation of oral-to-inhalation extrapolation con-cluded that, as a general rule, the. In Extrapolation of Dosinietric Relationships for Inhaled Particles and Gases, JD Crapo, ED Smolko, FJ Miller, JA Graham, AW Hayes, eds.

San Diego: Academic Press,pp. – Mercer R, Crapo JD. “Anatomical Modeling of Microdosimetry of Inhaled Particles and Gases in the Lung.” In Extrapolation of Dosimetric Relationships for Inhaled Particles and Gases, JD Crapo, ED Smolko, FJ Miller, JA Graham, AW Hayes, eds.

New York: Academic Press,pp. 69– Author: Sukhendu Debbarma Publisher: Indus Publishing ISBN: Size: MB Format: PDF, ePub, Docs View: Get Books. Refining Dosimetric Extrapolation Modeling of Inhaled Nanoparticles for Deriving of Pulmonary Biopersistence of Inhaled Particles. Gener al labor a t or y se tup St a tic Flo w -thr ough particle clearance model for the gas exchange region of the human respiratory tract Clear.

Rate =. Extrapolation of dosimetric relationships for inhaled particles and gases: Edited by J. Crapo, E. Smolko, F. Miller, J. Graham and A.

Hayes. Academic Press, San Diego, California. ISBN. gases, inhaled particles, clearance and retention kinetics, interspecies extrapolation the dose-response relationship.(1–3) These effect levels can be estimated for either cancer or noncancer endpoints.

Once the POD is identiﬁed, dosimetry models and meth- • Dosimetric adjustments are used to better account for our. Keywords: Inhalation aerosol; Lung deposition; Inertial impaction 1. Introduction The term 'respirable fraction' has been used extensively in the industrial hygiene and environmental medicine liter- ature to designate particles that, to various degrees, are capable of penetrating and depositing within the lungs [].

Gas filled Detectors Ionisation chamber Free air ion chamber Cavity chamber Cylindrical chambers Parallel chambers Extrapolation chambers Proportional counters GM counters Principle of Gas filled detector Basic structure of Response curve • Gas Multiplication: • Gas Multiplication is a consequence of increasing the electric field within.

The current RfC method provides guidelines for making the necessary dosimetric adjustments for gases and aerosols. Human equivalent concentrations for no-observed-adverse-effect levels in animals are determined by using mathematical relationships that adjust for regional deposition, solubility, ventilation rate, and blood:air partition.

EPA///F OCTOBER METHODS FOR DERIVATION OF INHALATION REFERENCE CONCENTRATIONS AND APPLICATION OF INHALATION DOSIMETRY Environmental Criteria and Assessment Office. NCRP, Deposition retention and dosimetry of inhaled radioactive substances, NCRP SC 2 Report, National Council on radiation Protection and Measurements, Bethesda, MD, Phalen, R.F.

The dose conversion coefficients (Dose/WLM) for miners and for adults and children exposed in the home and the corresponding values of the factor K are evaluated below. The factor K is referred to as the dosimetric risk extrapolation factor or, for convenience, as the K factor.

The variability of dose per WLM exposure and the K factor over a range of representative exposure scenarios in mines.

Attachment 1 of DPR () focused on inhaled gases and did not address dosimetric adjustment factors for inhaled particles or aerosols. For inhaled particles and aerosols, the committee recommends that DPR consider EPA () procedures to determine the appropriate dosimetric adjustment factor except for rat inhalation studies.

For rats, the. Several extensive reviews are available for dosimetry modeling of inhaled particles (4 – 9) and gas uptake. (4, 5, 10 – 16) The degree of detail or sophistication in the dosimetry estimation depends on the level of data available and the purpose of the risk assessment (e.g., screening assessment or full risk characterization).

Relationship of blood: gas and fat: blood partition coefficients to the attainment of periodic blood concentrations in the Fischer rat Example data array and inhalation.

The formula- tion of such a model for inhaled gases requires information on the physical, bio- logical, and chemical properties of the res- piratory tract, as discussed previously, as well as an understanding of the nature of gas transport in the lumen and air spaces (as discussed by Ultman, this volume).

Ingebrethsen ()in: Extrapolation of dosimetric relationships for inhaled particles and gases, (ed JD Crapo et al), Academic Press, pp. – Respiratory deposition model (ICRP 66) with deposition Minimum in – nm ( – µm) region. Smoke deposition efficiency is higher through deeper inhalation and pause.

Differences in the Chemical Composition of the Particulate Phase of Inhaled and Exhaled Cigarette Mainstream Smoke SC Moldoveanu 1 and FK St. Charles 2 1 R.J. Reynolds Tobacco Co., Reynolds Boulevard, Winston-Salem, NCUSA. Examples from inhalation toxicology including cadmium, diesel exhaust and asbestos will be used to demonstrate principles of lung dosimetry.

Future research needs include the incorporation of mechanistic data to develop mechanistically oriented dosimetric models for extrapolation modeling. To correct for intermolecular forces between gas particles, J.D.

van der Waals introduced a new term into the Ideal Gas Equation in By adding the term n 2 a/V 2 to pressure, van der Waals corrected for the slight reduction in pressure due to the interaction between gas particles: $P + \frac{an^2}{V^2}$.

Attachment 1 of DPR () focused on inhaled gases and did not address dosimetric adjustment factors for inhaled particles or aerosols. For inhaled particles and aerosols, the committee recommends that DPR consider EPA () procedures to determine the appropriate dosimetric adjustment factor except for rat inhalation studies.

At the time of the authors’ evaluation of dosimetric approaches, the only model covering gases and particles and regarded as potentially suitable for interspecies extrapolations in the case of limited data was the EPA approach. The validity of this methodology, however, differed for gases and particles, and some changes are proposed in the.

Extrapolation of Dosimetric Relationships for Inhaled Particles and Gases / James D. Crapo (Editor) / Organisation of Nematodes / Neil Argo Croll / Human Ecology and Infectious Diseases / Neil Argo Croll / The U.S. EPA advocates the assessment of health-effects data and calculation of inhaled reference doses as benchmark values for gauging systemic toxicity to inhaled gases.

The assessment often requires an inter- or intra-species dose extrapolation from no observed adverse effect level (NOAEL) exposure concentrations in animals to human. Other chapters deal with deposition and clearance of inhaled radioactive particles, inhalation of radioactive gases, and application of the model to estimate respiratory tract doses.

The model provides most of the flexibility needed to calculate doses to the respiratory tract for a wide range of exposure conditions and for specific individuals.

The human nose, on the other hand, is much less efficient at filtering inhaled particles and gases, so higher concentrations are delivered to the lung airways, possibly presenting effects lower in the respiratory tract than can be observed in inhalation studies in rodents.

For oral breathing in humans, this effect is even greater. inhalation risks from fugitive dusts from surface soils. B.3 Conclusions and Recommendations Based on the results presented in this appendix, OERR reached several conclusions regarding route-to-route extrapolation of inhalation benchmarks for the development of generic inhalation SSLs.

MWCNT to reach the benchmark response (BMR), whereas Ni3S2 needed only to be inhaled at a very low concentration to reach its BMR at the 3-month timepoint. In order to extrapolate the rat to a human equivalent concentration (HEC), dosimetric extrapolation with rat-specific and human-specific particle deposition models should finally be carried out.

In Inhalation Toxicology - Extrapolation of dosimetric relationships for inhaled particles and gases, Dungworth D, Kimmerle-Lewkowski J, McClellan R & Stober W (eds), pp.

New York: Springer-Verlag, Purchase Inhaled Particles V - 1st Edition. Print Book & E-Book. ISBN   Publications. Showing all journal articles & 51 books available. Journal Articles. 7/16/ Driscoll KE, Borm PA, Chaudhuri I, Levy L, Yong M, Warheit D, McCunney R, Oberdörster G.

"Comment on Saber et al. (), "Commentary: the chronic inhalation study in rats for assessing lung cancer risk may be better than its reputation"." Particle and fibre toxicology. Jul 16; 17(1) In: Extrapolation of dosimetric relationships for inhaled particles and gases.

Academic Press, NY, pp. Also, while clearance is obviously slow for insoluble particles, at one point an equilibrium will exist. For example, coal miners will have about 5 to 15 mg of coal dust/g of lung despite chronic exposure. Extrapolation of Dosimetric Relationships for Inhaled Gases and Particles.

J Toxicol and Environ Health Symposium Proceedings (). Tepper, J.S., Costa, D.L., and Lehmann JR. Extrapolation of Animal Data to Humans: Homology of Pulmonary Physiological Responses with Ozone Exposure. Toxicology of the Lung.

Ed. 7. Ingebrethsen, B. J.: The Physical Properties of Mainstream Cigarette Smoke and their Relationship to Deposition in the Respiratory Tract; in: Extrapolation of Dosimetric Relationships for Inhaled Particles and Gases, edited by J.

D. Crapo, Academic Press. The dispersion of the powder into particles that enter into the inhaled fraction is produced by the formation of turbulent airflows inside the powder container, which break the powder agglomerations up into smaller-sized particles and separate the transport particles from the drug.

50 The particles that are generated have a final MMAD that.effectively absorbs water-soluble and reactive gases and va-pors, traps inhaled particles, and metabolizes airborne xeno-biotics(Brain,).Withitsroleasan“airconditioner”and a “defender” of the lower respiratory tract, the nose may also be vulnerable to acute or chronic injury caused by exposure.

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