Document Detail

Concentration-time-response modeling for acute and short-term exposures.
MedLine Citation:
PMID:  16111795     Owner:  NLM     Status:  MEDLINE    
Risk of health effects from acute and short-term exposure depends on exposure time as well as exposure concentration. A general approach to extending a concentration-response model to include time as a variable is described using mortality of rats exposed to hydrogen sulfide (H(2)S) as an example. This particular example resulted in a logit model with concentration-time (c-t) relationship linear in time and log-concentration. It provided an improved statistical fit, based on the Akaike information criterion in the observed time range, 30 m-360 m, over implementing the c-t relationship of [ten Berge, W.F., Zwart, A., Appelman, L.M., 1986. Concentration-time mortality response relationship of irritant and systemically acting vapours and gases. J. Hazard. Mater. 13, 301--309] as a default in the logit model. This approach also indicated that there might be a fundamental difference in the relationship between concentration, time, and response at short exposure times, somewhere less than 30 m, a hypothesis for further consideration from a biological perspective. In general, the proposed approach provides flexibility to develop a concentration-time-response model, and the associated concentration-time relationship, from the data. Interpretation and potential implications, however, need to be considered within the context of biological plausibility as well. Implementation of the proposed approach requires adequate data for separate concentration-response modeling at each of several exposure durations.
Kenneth G Brown; Gary L Foureman
Related Documents :
10660985 - Effect of different grouping strategies in developing estimates of personal exposures: ...
15986055 - Field test results of an automated exposure assessment tool, the local positioning syst...
19440405 - Application of bayesian methods to exposure assessment of area concentrations at a rubb...
12775065 - Selective remediation of contaminated sites using a two-level multiphase strategy and g...
15503675 - Modeling compositional heterogeneity.
19684205 - Kinematics, hydrodynamics and force production of pleopods suggest jet-assisted walking...
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  Regulatory toxicology and pharmacology : RTP     Volume:  43     ISSN:  0273-2300     ISO Abbreviation:  Regul. Toxicol. Pharmacol.     Publication Date:  2005 Oct 
Date Detail:
Created Date:  2005-09-12     Completed Date:  2006-07-12     Revised Date:  2007-11-15    
Medline Journal Info:
Nlm Unique ID:  8214983     Medline TA:  Regul Toxicol Pharmacol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  45-54     Citation Subset:  IM    
KBinc, Chapel Hill, NC 27516, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Air Pollutants / toxicity*
Databases, Factual
Dose-Response Relationship, Drug
Environmental Exposure*
Hydrogen Sulfide / toxicity*
Meta-Analysis as Topic
Models, Biological*
Time Factors
Reg. No./Substance:
0/Air Pollutants; 7783-06-4/Hydrogen Sulfide

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Depression, implicit memory, and self: a revised memory model of emotion.
Next Document:  Aberrant folate status in schizophrenic patients: what is the evidence?