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Scientific reviews find Three Mile Island caused near-background radiation and minimal off-site health effects.

The Claim

Scientists in relevant fields widely agree that the health and environmental effects of the 1979 Three Mile Island nuclear accident were very low.

Verified by Lenz ·

The Short Version

The evidence strongly supports a broad scientific view that Three Mile Island caused very low off-site radiological health and environmental harm. Government reviews, academy assessments, and long-term epidemiology generally found exposures near background and no detectable population-level physical effects. A few studies raised limited cancer-signal concerns, and the claim is broad enough to understate psychosocial impacts, so some caution is warranted.

Caveats

  • This conclusion mainly concerns radiological physical health effects and environmental contamination, not psychological stress, social disruption, or economic impacts.
  • A small minority of epidemiological studies reported possible localized or subgroup cancer signals, but these did not overturn the dominant assessment of very low overall impact.
  • Several cited summaries come from industry-aligned organizations; the strongest support comes from government, National Academies, and peer-reviewed studies.

The Receipts

  1. Backgrounder on the Three Mile Island Accident

    U.S. Nuclear Regulatory Commission

  2. 5 Facts to Know About Three Mile Island

    U.S. Department of Energy

  3. Population dose and health impact of the accident at the Three Mile Island Nuclear Station. Preliminary estimates for the period March 28, 1979--April 7, 1979

    U.S. Department of Energy / OSTI

  4. Follow-up Studies on Biological and Health Effects Resulting from the Three Mile Island Nuclear Power Plant Accident of March 28, 1979

    National Academies Press

  5. Health Effects of Nuclear Reactor Accidents: TMI, Chernobyl, Fukushima (training slides)

    National Cancer Institute (DCEG)

  6. Three Mile Island Accident

    World Nuclear Association

  7. Investigations of Reported Plant and Animal Health Effects in the Three Mile Island Area (NUREG-0738, EPA 600/4-80-049)

    U.S. Environmental Protection Agency / U.S. Nuclear Regulatory Commission

  8. A reevaluation of cancer incidence near the Three Mile Island nuclear plant: the collision of evidence and assumptions

    American Journal of Public Health (via PubMed Central)

  9. Population exposure and health impact of the accident at the Three Mile Island Nuclear Station

    U.S. Department of Energy / OSTI

  10. Cancer mortality and morbidity following the Three Mile Island nuclear power plant accident: 1979–1998

    PubMed (Environmental Health Perspectives)

+ 7 more sources — see the full list on Lenz

Filed Under

Three Mile Island Accident