Validation of a brief screening instrument for chemical intolerance in a large U.S. national sample

Raymond F. Palmer, Tatjana Walker, David Kattari, Rudy Rincon, Roger B. Perales, Carlos R. Jaén, Carl Grimes, Dana R. Sundblad, Claudia S. Miller

Research output: Contribution to journalArticlepeer-review


Background: Chemical intolerance (CI) is characterized by multisystem symptoms triggered by low levels of exposure to xenobiotics including chemicals, foods/food additives, and drugs/medications. Prior prevalence estimates vary from 8–33% worldwide. Clinicians and researchers need a brief, practical screening tool for identifying possible chemical intolerance. This large, population-based study describes the validation of a three-item screening questionnaire, the Brief Environmental Exposure and Sensitivity Inventory (BREESI), against the international reference standard used for assessing chemical intolerance, the Quick Environmental Exposure and Sensitivity Inventory (QEESI). Methods: More than 10,000 people in the U.S. responded to the BREESI and the QEESI in a population-based survey. We calculated the overall prevalence of CI in this sample, as well as by gender, age, and income. Common statistical metrics were used to evaluate the BREESI as a screener for CI against the QEESI. Results: The prevalence estimate for QEESI-defined chemical intolerance in the U.S. was 20.39% (95% CI 19.63%–21.15%). The BREESI had 91.26% sensitivity (95% CI: 89.20%–93.04%) and 92.89% specificity (95% CI: 91.77%–93.90%). The positive likelihood ratio was 12.83 (95% CI: 11.07–14.88), and the negative likelihood ratio was 0.09 (95% CI: 0.08–0.12). Logistic regression demonstrates that the predicted probability of CI increased sharply with each increase in the number of BREESI items endorsed (Odds Ratio: 5.3, 95% CI: 4.90–5.75). Conclusions: Chemical intolerance may affect one in five people in the U.S. The BREESI is a new, practical instrument for researchers, clinicians, and epidemiologists. As a screening tool, the BREESI offers a high degree of confidence in case ascertainment. We recommend: screen with the BREESI, confirm with the QEESI.

Original languageEnglish (US)
Article number8714
JournalInternational Journal of Environmental Research and Public Health
Issue number16
StatePublished - Aug 2 2021


  • Chemical intolerance
  • Drug intolerance
  • Food intolerance
  • Multiple chemical sensitivity
  • Prevalence
  • Toxicant-induced loss of tolerance

ASJC Scopus subject areas

  • Pollution
  • Public Health, Environmental and Occupational Health
  • Health, Toxicology and Mutagenesis


Dive into the research topics of 'Validation of a brief screening instrument for chemical intolerance in a large U.S. national sample'. Together they form a unique fingerprint.

Cite this