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Updated: Dec 18, 2025

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Comparison between Communicated and Calculated Exposure Estimates Obtained through Three Modeling Tools.

Andrea Spinazzè1, Francesca Borghi1, Daniele Magni1

  • 1Dipartimento di Scienza e Alta Tecnologia, Università degli Studi dell'Insubria, Via Valleggio 11, 22100 Como, Italy.

International Journal of Environmental Research and Public Health
|June 18, 2020
PubMed
Summary
This summary is machine-generated.

Generic REACH chemical risk assessments may not reflect actual workplace conditions. Studies show poor correlation between communicated and calculated exposures, leading to potentially unsafe "false safe" scenarios. Scenario-specific evaluations are recommended for accurate chemical risk assessment.

Keywords:
ECETOC TRAREACHSTOFFENMANAGER®advanced REACH tool (ART)exposure scenariooccupational exposure assessmentoccupational exposure modelsrisk characterization ratioscaling

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Area of Science:

  • Chemical safety and risk assessment
  • Industrial hygiene
  • Regulatory compliance

Background:

  • The Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) legislation mandates risk assessments for industrial chemicals.
  • Extended Safety Data Sheets (e-SDS) communicate estimated exposure scenarios (ES) and risk characterization ratios (RCRs).
  • Generic ES may not accurately represent actual workplace exposure conditions.

Purpose of the Study:

  • To evaluate the accuracy of REACH risk assessment approaches in industrial settings.
  • To compare communicated exposure estimates and RCRs with those calculated for actual, observed scenarios.
  • To identify factors causing bias between estimated and actual chemical exposures and risks.

Main Methods:

  • Compared communicated ES and RCRs with calculated values for 49 scenarios across three companies.
  • Utilized ECETOC TRA v.3.1, STOFFENMANAGER® v.8.0, and ART tools for exposure assessment.
  • Calculated RCRs by dividing estimated exposures by derived no-effect levels (DNELs).

Main Results:

  • Generally, calculated exposures and RCRs were lower than communicated values.
  • A poor correlation was observed between communicated and calculated exposures and RCRs.
  • Some observed scenarios yielded higher calculated exposures and RCRs than communicated, indicating 'false safe' situations.

Conclusions:

  • Generic ES provided in e-SDSs may not adequately represent actual working, exposure, and risk conditions.
  • The use of generic scenarios for risk assessment across all companies is questionable.
  • Downstream users should conduct scenario-specific evaluations for more representative chemical risk estimates.