Baby Safety / Compounds / Thorium-232 (²³²Th)

Is Thorium-232 (²³²Th) safe for babies and kids?

Moderate risk for kids

Not medical or professional safety advice, and not a substitute for a qualified clinician — consult one. Full disclaimer →

Infants are more vulnerable to Thorium-232 (²³²Th) than children or adults due to immature hepatic/renal clearance, higher intake-to-body-weight ratio, rapid organ development, and increased gastrointestinal absorption.

What is thorium-232 (²³²th)?

The IUPAC name is thorium.

Also known as: thorium, 232Th, 60YU5MIG9W, 90Th.

IUPAC name
thorium
CAS number
7440-29-1
Molecular formula
Th
Molecular weight
232.038 g/mol
SMILES
[Th]
PubChem CID
23960

Risk for babies

Moderate risk

Infants are more vulnerable to Thorium-232 (²³²Th) than children or adults due to immature hepatic/renal clearance, higher intake-to-body-weight ratio, rapid organ development, and increased gastrointestinal absorption.

Neonates and infants up to 12 months have incomplete blood-brain barrier development, immature Phase I/II metabolic enzymes (particularly CYP3A4, UGT1A1), and higher gastrointestinal permeability. Equivalent doses produce higher internal concentrations and longer residence times.

What to do: Minimize infant exposure through source control. For breastfeeding mothers: reduce maternal exposure. For formula-fed infants: use certified low-migration bottles and verified water sources. Consult pediatrician regarding any concerns.

Risk for pregnant and nursing people

Context-dependent

Pregnancy alters the metabolism and distribution of Thorium-232 (²³²Th), potentially increasing fetal exposure. The developing embryo/fetus is vulnerable during organogenesis (weeks 3-8) and neurological development. Placental transfer should be assumed.

No specific reproductive toxicity data identified, but pregnancy-specific safety data is limited for most chemicals. Precautionary minimization of exposure is recommended.

What to do: Minimize exposure during pregnancy and lactation. Consult healthcare provider regarding specific risks. Consider alternative products with lower hazard profiles.

Regulatory consensus

2 regulatory and scientific bodies have classified Thorium-232 (²³²Th). The classifications differ — that's the data.

AgencyYearClassificationNotes
IARC—Group 1
EPA CTX / IARC—Group 1 - Carcinogenic to humans

Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.

Where kids encounter thorium-232 (²³²th)

  • Industrial Facilities — Manufacturing plants, Chemical storage areas, Waste treatment sites
  • Occupational Environments — Factories, Warehouses, Transportation vehicles

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Thorium-232 (²³²Th):

  • Shielding / distance / time (radiation protection)
    Trade-offs: Removes 95-99% of dissolved contaminants including metals, PFAS, nitrates; wastes 2-4 gallons per gallon produced (improving with newer systems); removes beneficial minerals; $0.05-0.25/gallon; requires pre-treatment for longevity.
    Relative cost: 1.2-2×

Frequently asked questions

Is thorium-232 (²³²th) safe for kids?

Infants are more vulnerable to Thorium-232 (²³²Th) than children or adults due to immature hepatic/renal clearance, higher intake-to-body-weight ratio, rapid organ development, and increased gastrointestinal absorption.

What products contain thorium-232 (²³²th)?

Thorium-232 (²³²Th) appears in: Manufacturing plants (Industrial facilities); Chemical storage areas (Industrial facilities); Factories (Occupational environments); Warehouses (Occupational environments).

What should I do if my child is exposed to thorium-232 (²³²th)?

Minimize infant exposure through source control. For breastfeeding mothers: reduce maternal exposure. For formula-fed infants: use certified low-migration bottles and verified water sources. Consult pediatrician regarding any concerns.

See Thorium-232 (²³²Th) in the baby app

Look up products containing thorium-232 (²³²th), compare to alternatives, and explore the full data record.

Open in baby View raw API data

Sources (6)
  1. IARC Monographs Volume 78 (2001): "Thorium-232 and its decay products, administered intravenously as a colloidal dispersion of 232-ThO2 (Thorotrast), are carcinogenic to humans (Group 1)" — liver cancer/angiosarcoma. INDIVIDUALLY evaluated (also Vol 100D). (2001) — regulatory
  2. UNSCEAR 2008 Report Vol I Annex B: Exposures of the Public and Workers from Various Sources of Radiation (natural radioactivity incl. thorium) (2008) — regulatory
  3. US EPA Radionuclide Basics: Thorium (incl. Th-232; alpha emitter; lung/bone cancer on inhalation) (2020) — regulatory
  4. ATSDR Toxicological Profile for Thorium (2019) — regulatory
  5. ICRP Publication 103 — 2007 Recommendations of the International Commission on Radiological Protection (2007) — regulatory
  6. US NRC 10 CFR 20 — Standards for Protection Against Radiation (2020) — regulatory

Reference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for medical, pediatric, legal, or regulatory advice. Why we built ALETHEIA →