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Health risk assessment of fluctuating concentrations using lognormal models
1Department of Environmental Health, University of Cincinnati, Ohio, USA. Bernard.Saltzman@uc.edu
Journal of the Air & Waste Management Association (1995)
|December 12, 1997
Summary
This study introduces a mathematical model to assess health risks from fluctuating environmental concentrations. The model uses log-normal distributions to quantify risk by analyzing the overlap between concentration and dose-response patterns.
Area of Science:
- Environmental Health
- Toxicology
- Mathematical Modeling
Background:
- Assessing health risks from fluctuating environmental concentrations is complex.
- Existing models may not fully capture the variability in both exposure levels and individual responses.
- Understanding the interplay between concentration patterns and dose-response curves is crucial for accurate risk assessment.
Purpose of the Study:
- To develop a mathematical model for quantifying health risk rates associated with fluctuating environmental concentrations.
- To theoretically derive and validate the log-normal distribution patterns for both concentration and dose-response.
- To provide a method for calculating health risks based on population diversity and emission variability.
Main Methods:
- Proposed a mathematical model integrating time-averaged concentrations as doses.
- Derived dose-response patterns as cumulative log-normal curves due to individual diversity.
- Modeled concentration patterns as log-normal distributions reflecting emission and dispersion variability.
- Utilized numerical integration with two generalized parameters to evaluate joint probabilities.
Main Results:
- Health risk is determined by the overlap between the concentration distribution's right tail and the dose-response curve's left tail.
- Two generalized parameters quantify this overlap: relative geometric standard deviation and distance between geometric mean concentration and 50% adverse response concentration.
- Results are presented graphically and in tabular form for practical application.
Conclusions:
- The developed mathematical model offers a convenient method for calculating health risks from fluctuating concentrations.
- Accurate risk assessment is achievable when dose-response parameters are known, allowing calculation for various concentration patterns.
- The model accounts for population diversity and emission source variability, enhancing risk assessment accuracy.
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