Lunar & Mars dust
Also: Celestial dust risk
Hostile/Closed EnvironmentPulmonaryEVA & Surface OpsLunar surfaceMars transit & surfacePublicClinicianResearcher
- NASA has a lunar dust exposure limit of 0.3 mg/m³, based on rodent studies with real Apollo dust. ◆◆◆◇ Moderate · M E
- Human health effects of lunar dust are largely uncharacterized, and Mars dust even more so. ◆◇◇◇ Very low · E
Proposed certainty (◆ High → ◇ Very low) and evidence-type tags: F flight · A analog · M model/animal · C computational · E expert/operational/standards. AI-proposed, pending reviewer confirmation. How to read the grades.
NASA risk title (verbatim)
Risk of Adverse In-Mission Health and Performance Effects and Long-Term Health Effects Due to Celestial Dust Exposure
NASA short title: Dust · HRP element: Exploration Medical Capability (ExMC) · Status: Active [current research ongoing] [1]
What it is
Surface spacewalks bring dust into habitats. This risk covers harm to the lungs, heart, eyes and skin from breathing or touching lunar and Martian dust [1]. It doesn’t apply to missions in low Earth orbit [1].
Current evidence
- From rodent inhalation studies with real Apollo 14 lunar dust, plus expert review, NASA set an exposure standard of 0.3 mg/m³ for six months of episodic exposure. It is a permissible exposure limit (PEL) in NASA-STD-3001 Vol. 2 [1].
- The standard assumes dust settles deeper in the lungs in low gravity but that total dust load is lower. NASA says this assumption still needs research [1].
- Lunar polar ice and subsurface soil may contain volatile chemicals of toxicological concern, such as mercury, ammonia and hydrogen sulfide [1].
NASA’s risk posture
NASA scores each risk for each design reference mission (DRM) as likelihood × consequence (LxC). Both run from 1 (lowest) to 5 (highest) on the HSRB’s 5×5 matrix [1][3]. Each score comes with a disposition, such as “Accepted”, “Requires Characterization” or “Requires Mitigation”. These ratings were last approved by NASA’s Human System Risk Board (HSRB) in 3/2024 [1].
| Mission | Duration | In-mission (operations) | Long-term health |
|---|---|---|---|
| LEO | Short (under 30 d) | Not applicable | Not applicable |
| LEO | Long (30 d–1 yr) | Not applicable | Not applicable |
| Lunar orbit | Short | 1x2 · Accepted | 1x2 · Accepted |
| Lunar orbit | Long | 1x2 · Accepted | 1x2 · Accepted |
| Lunar orbit + surface | Short | 2x1 · Accepted with Monitoring | 2x2 · Accepted with Monitoring |
| Lunar orbit + surface | Long | 3x3 · Requires Mitigation | 3x4 · Requires Mitigation |
| Mars preparatory | Under 1 yr | Not applicable | Not applicable |
| Mars planetary | 730–1,224 d | 4x4 · Requires Characterization | 4x4 · Requires Characterization |
NASA marks low Earth orbit as not applicable because those missions don’t involve celestial dust [1].
Copied from the Human Research Roadmap on 2026-10-14. Ratings change. Check the live record before citing.
Open knowledge gaps
NASA lists 1 knowledge gaps for this risk, 1 of them open as of 2026-10-14 [1]. Each gap ID links to its page on the Human Research Roadmap (HRR).
Show NASA’s gap list (verbatim)
| Gap | NASA gap statement | Status |
|---|---|---|
| Dust-101 | We need to determine if there are significant differences in the acute and chronic toxicity of dusts from different exploration targets, and whether existing permissible exposure limits can be applied or if new PELs are needed. | Open |
See also Open questions.
Active countermeasure research
- Engineering controls. The lunar dust standard is being used to design controls that keep exposure below the limit [1].
- Current research. Work is focused on whether lunar dust can trigger allergies. Gap Dust-101 asks whether dusts from different destinations differ in toxicity and whether the existing limits still apply [1].
Project-level detail, including status, investigators and results, is in the NASA Task Book and on each HRR gap page.
Clinical articles
For practical, clinic-facing guidance, see:
Evidence profile
- Overall certainty
- ◆◆◇◇ Low (proposed)
- Evidence types
- M · Model / animalE · Expert / operational / standards
- Literature through
- 2026-10-14
- NASA source
- Human Research Roadmap risk page (last published 05/13/25; read 2026-10-14)
Requirements referenced 0
No NASA-STD-3001 requirement maps directly to this page. See the standards quick reference.
References 3
- NASA Human Research Roadmap. Risk record: “Risk of Adverse In-Mission Health and Performance Effects and Long-Term Health Effects Due to Celestial Dust Exposure”. Accessed 2026-10-14. humanresearchroadmap.nasa.gov/Risks/?i=82 NASA E
- NASA Human Research Program. Evidence report for the Celestial Dust risk (approved August 4, 2015). humanresearchroadmap.nasa.gov/evidence/reports/Dust.pdf NASA E
- Antonsen EL, et al. Updates to the NASA human system risk management process for space exploration. NPJ Microgravity. 2023;9:72. doi:10.1038/s41526-023-00305-z PMID:37679359 Peer-reviewed E
Machine-checked on 2026-10-14: each URL resolved, each DOI's title/journal/year matched via Crossref, and claims were checked against the source text (abstract or full NASA page). Human verification against full text is still required before review. NASA documents are U.S. Government works (public domain) and are summarized with attribution; journal articles are summarized, not reproduced.
Article info
- Authors
- Pending (AI-assisted draft)
- Reviewer
- Pending review
- Last reviewed
- Pending review
- Literature through
- 2026-10-14
- AI-assisted
- Yes (disclosed)
- COI
- Pending
- License
- CC BY-SA 4.0
- Use
- Educational only · Disclaimer
- Cite this version
- Pending first edition