Neurobehavioral properties of chemical sensitivity syndromes.
Weiss, B · Neurotoxicology · 1998
Quick Summary
This review examines four conditions that involve chemical sensitivity and fatigue-like symptoms: Multiple Chemical Sensitivity Syndrome, Sick Building Syndrome, Chronic Fatigue Syndrome, and Gulf War Syndrome. The authors explore different theories about why people develop these conditions, including psychiatric factors, learned behavioral responses, changes in how the nervous system works, and problems with the immune system's stress response. The review suggests that laboratory studies and controlled clinical trials could help determine which explanations are correct.
Why It Matters
This review is valuable because it positions ME/CFS within a broader framework of chemically-sensitive syndromes and explores multiple biological and psychological mechanisms that could explain symptom development. Understanding these mechanisms may help researchers identify biomarkers and develop targeted treatments for ME/CFS patients, many of whom report chemical sensitivities.
Observed Findings
Multiple Chemical Sensitivity Syndrome, Sick Building Syndrome, Chronic Fatigue Syndrome, and Gulf War Syndrome share patterns of subjective neurobehavioral complaints.
Chemical exposures are inconsistently characterized across these syndromes, often at low environmental levels.
Conventional clinical signs are typically absent in these conditions despite patient symptom reports.
Proposed mechanisms span psychiatric, behavioral, neuropharmacological, and psychoneuroimmunological domains.
No single etiological pathway has been definitively established for any of these syndromes.
Inferred Conclusions
Chemical sensitivity syndromes share overlapping neurobehavioral features but heterogeneous etiological explanations.
Multiple mechanisms—psychiatric, behavioral, neurological, and immunological—may contribute to symptom development across these conditions.
Animal models and controlled clinical trials are necessary to test competing mechanistic hypotheses and differentiate real biological effects from behavioral sensitization.
The ambiguity in chemical causation and absence of objective clinical signs necessitate experimental approaches to clarify pathophysiology.
Remaining Questions
What This Study Does Not Prove
This review does not establish that chemical exposures cause ME/CFS, nor does it prove which proposed mechanism (psychiatric, behavioral, neurological, or immunological) is primary or correct. It is a narrative synthesis of existing literature without new empirical data, and therefore cannot definitively establish causation or validate any single explanatory model.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →