Reference summary — not medical advice or a personal risk estimate.
Radium-226 and its decay products
Quick answer
Classified as Group 1 — carcinogenic to humans, based on sufficient evidence in humans. Radiation exposure. Historical medical use, occupational (nuclear industry, radiology), or environmental contamination.
Summary
Classified by IARC as Group 1 — carcinogenic to humans. Strong evidence. (Vol 78, 100D, 2012)
What's not established
This classification is based on sufficient evidence in humans that this factor can cause cancer. It does not establish a safe exposure threshold, your personal risk, or how this factor's risk compares in size to other Group 1 agents — hazard classifications are not ranked by magnitude.
Regional relevance
global
Evidence sources
Every claim on this page traces back to one of these. Click through to read the primary document yourself.
Primary sources
IARC
IARC Monographs — Agents Classified Alphabetically (Vols 1–123)
Last reviewed: November 2026
Official reference list
A government list some readers use alongside the primary evidence. Meyron is not affiliated with it. A chemical being listed does not by itself describe a risk from any particular product.
- California Prop 65 list
State of California's list of chemicals known to cause cancer or reproductive harm.