Mercury (Blood) · high result
What does a high Mercury (Blood) mean?
Short answer
High blood mercury in adults is nearly always dietary methylmercury from large predatory fish — tuna (especially bigeye and ahi), swordfish, king mackerel, shark, tilefish — with levels tracking the last month or two of intake. Occupational or dental amalgam exposure shows up mainly in urine, not blood. Above about 10 mcg/L warrants cutting high-mercury fish; above 50–100 needs medical evaluation. Mercury crosses the placenta, so pregnancy planning lowers the threshold for action.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
When does this result need same-day care?
- Blood mercury above ~100 mcg/L, or any level with tremor, gait problems or vision changes — prompt medical evaluation
What is the normal range for Mercury (Blood)?
- age 18+: 0.000 – 10.0 mcg/L
Often reflects high consumption of large predatory fish (tuna, swordfish, shark) or occupational exposure.
Full reference table, citations and testing options: Mercury (Blood) biomarker page.
What are the common causes of high Mercury (Blood)?
- Frequent consumption of large predatory fish (tuna, swordfish, shark, king mackerel, tilefish, marlin)
- Some traditional remedies and skin-lightening creams
- Occupational exposure to mercury vapor (dental, industrial) — mostly urinary
- Broken thermometers or fluorescent bulbs (acute, usually minor)
What symptoms go with high Mercury (Blood)?
- Often none
- Tingling around the mouth and in fingers and toes, tremor, poor coordination, vision or hearing changes at higher levels
- Fatigue, memory and mood changes
What do clinicians usually check next?
- Switch to low-mercury fish (salmon, sardines, shrimp, pollock, canned light tuna in moderation); retest in 3 months
- If pregnant or planning: follow FDA/EPA fish advice and retest
- Neurological review for symptoms; urine mercury if occupational exposure is possible
How do you recheck Mercury (Blood)?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Environmental Toxins Panel | Panel · 4 tests | $1049.99 | No | 7–14 business days |
| Heavy Metals Panel (Basic) | Test · 4 biomarkers | $84.99 | No | 5–7 business days |
Common questions
How much tuna is too much?
For most adults, more than two or three servings a week of albacore or ahi tuna over months can push blood mercury above 10 mcg/L. Canned light (skipjack) tuna carries roughly a third the mercury.
Do dental fillings raise blood mercury?
Amalgam releases small amounts of mercury vapor that show up in urine more than blood, at levels well below those associated with harm. Blood mercury mainly reflects fish intake.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.