Summary
| Direction in Gulf War Illness | ↓ Reduced — lower than in the comparison group |
|---|---|
| Category | Exposure |
| Also described as | OP pesticide detoxification |
| Compared against | HGV (healthy Gulf War veteran controls) |
| Associated symptoms | Organophosphate sensitivity |
| Test type | Blood test (serum / plasma / whole blood) |
| Source | Gean et al. 2021 — doi:10.1016/j.lfs.2021.119456 |
| Condition atlas | Gulf War Illness Biomarker Atlas |
Related Exposure markers in Gulf War Illness
- PON1 Q192R polymorphism ↕
- Butyrylcholinesterase (BChE) ↕
- Acetylcholinesterase (AChE) ↕
- DNA adducts (pesticide-related) ↑
- Depleted uranium (urinary) ↕
- Sarin/cyclosarin exposure markers ↕
Full list: Gulf War Illness Biomarker Atlas.
Frequently asked questions
Is PON1 (paraoxonase 1) activity high or low in Gulf War Illness?
Reduced. Studies summarised in the OSMF atlas report lower PON1 (paraoxonase 1) activity in Gulf War Illness than in healthy Gulf War veteran controls. Source: Gean et al. 2021.
What symptoms is PON1 (paraoxonase 1) activity associated with in Gulf War Illness?
The cited literature associates this marker with Organophosphate sensitivity. These are population-level associations and do not mean the marker causes the symptoms.
Which test measures PON1 (paraoxonase 1) activity?
It is measured as a blood test (serum / plasma / whole blood). Many of the cited studies used research-grade assays, so clinical availability may vary.
Is one abnormal PON1 (paraoxonase 1) activity result diagnostic of Gulf War Illness?
No. No single biomarker is diagnostic of Gulf War Illness. PON1 (paraoxonase 1) activity findings come from group comparisons, overlap considerably between patients and controls, and vary with study design, timing and comparison group. A result should be interpreted by a clinician alongside symptoms, history and other tests.
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Last reviewed: 2026-06-29 · Page generated from gulf-war-illness.json · Browse: Gulf War Illness atlas · Biomarker Index · All marker pages
Disclaimer: This page is an educational synthesis of published, peer-reviewed research and is not medical advice. Biomarker findings vary across studies with case definitions, comparison groups, timing and assay methods. Direction of change reflects the predominant finding in the cited source and does not establish a diagnostic threshold. Discuss any test result with a qualified clinician.