Baby Safety / Compounds / Diethylstilbestrol (DES)

Is Diethylstilbestrol (DES) safe for babies and kids?

Extreme risk for kids

Infants have immature drug-metabolizing enzymes (CYP450 ontogeny), reduced renal clearance, and different volume of distribution. Accidental exposure or breast milk transfer of Diethylstilbestrol (DES) poses heightened risk.

What is diethylstilbestrol (des)?

The IUPAC name is 4-[(E)-4-(4-hydroxyphenyl)hex-3-en-3-yl]phenol.

Also known as: 4-[(E)-4-(4-hydroxyphenyl)hex-3-en-3-yl]phenol, diethylstilbestrol, Stilboestrol, Distilbene.

IUPAC name
4-[(E)-4-(4-hydroxyphenyl)hex-3-en-3-yl]phenol
CAS number
56-53-1
Molecular formula
C18H20O2
Molecular weight
268.3 g/mol
SMILES
CCC(=C(CC)C1=CC=C(C=C1)O)C2=CC=C(C=C2)O
PubChem CID
448537

Risk for babies

Extreme risk

Infants have immature drug-metabolizing enzymes (CYP450 ontogeny), reduced renal clearance, and different volume of distribution. Accidental exposure or breast milk transfer of Diethylstilbestrol (DES) poses heightened risk.

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

Very high risk

Diethylstilbestrol (DES) poses pregnancy risk through potential teratogenicity, altered pharmacokinetics (increased blood volume, changed CYP activity), and placental transfer. FDA pregnancy category should be evaluated.

Suspected reproductive toxicant (GHS H361) or suspected endocrine disruptor. Precautionary approach warranted. Animal studies or limited human data suggest developmental toxicity potential.

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

Regulatory consensus

8 regulatory and scientific bodies have classified Diethylstilbestrol (DES). The classifications differ — that's the data.

AgencyYearClassificationNotes
IARC2012Group 1
US EPA2000carcinogenic to humans
EPA CTX / NTP RoCKnown Human Carcinogen
EPA CTX / IARCGroup 1 - Carcinogenic to humans
EPA CTX / CalEPAKnown human carcinogen
EPA CTX / GenetoxGenotoxicity: positive (Ames: negative, 10 positive / 7 negative reports)
EPA CTX / GenetoxGenotoxicity: positive (Ames: negative, 10 positive / 7 negative reports)
EPA CTX / Skin-EyeSkin Sensitization: SkinSens1 (score: high)

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 diethylstilbestrol (des)

  • Industrial FacilitiesManufacturing plants, Chemical storage areas, Waste treatment sites
  • Occupational EnvironmentsFactories, Warehouses, Transportation vehicles

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Diethylstilbestrol (DES):

  • Alternative drug class; Non-pharmacological therapy; Lowest effective dose
    Trade-offs: Direct chemical substitution requires verification that the replacement does not introduce new hazards (regrettable substitution). Conduct full hazard assessment of proposed alternative before adoption.
    Relative cost: 1.2-2×

Frequently asked questions

Is diethylstilbestrol (des) safe for kids?

Infants have immature drug-metabolizing enzymes (CYP450 ontogeny), reduced renal clearance, and different volume of distribution. Accidental exposure or breast milk transfer of Diethylstilbestrol (DES) poses heightened risk.

What products contain diethylstilbestrol (des)?

Diethylstilbestrol (DES) 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 diethylstilbestrol (des)?

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.

Why do regulators disagree about diethylstilbestrol (des)?

Diethylstilbestrol (DES) has been classified by 8 agencies including IARC, US EPA, EPA CTX / NTP RoC, EPA CTX / IARC, EPA CTX / CalEPA, with differing conclusions. 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. See the regulatory consensus table on this page for the full picture.

See Diethylstilbestrol (DES) in the baby app

Look up products containing diethylstilbestrol (des), compare to alternatives, and explore the full data record.

Open in baby View raw API data

Sources (2)

  1. IARC Monographs Volume 100A: Pharmaceuticals — DES Group 1; Transplacental CCAV in DES Daughters; Breast Cancer in DES Mothers; Herbst 1971 Landmark Paper; Reproductive Tract Abnormalities; Growth Promotion Livestock Use Banned 1979 (2012) — iarc_monograph
  2. US EPA Diethylstilbestrol: Carcinogenic to Humans; Paradigmatic Transplacental Carcinogen; 1971 Pregnancy Ban; DES Daughters Follow-Up Study; Aquatic Estrogenic Potency; Feedlot Runoff Legacy Contamination; Fish Feminization (2000) — regulatory

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