Baby Safety / Compounds / R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene)

Is R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene) safe for babies and kids?

Moderate risk for kids

Infants are more vulnerable to R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene) 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 r-1234ze(e) (trans-1,3,3,3-tetrafluoropropene)?

Also known as: Ethiocholanolone, TMS, 3A-Hydroxy-5B-androstan-17-one, bis-TMS.

CAS number
29118-25-0
Molecular formula
C3H2F4
Molecular weight
114.04 g/mol
SMILES
CC12CCC(CC1CCC3C2CCC4(C3CCC4O[Si](C)(C)C)C)O[Si](C)(C)C
PubChem CID
6431230

Risk for babies

Moderate risk

Infants are more vulnerable to R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene) 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 R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene), 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

4 regulatory and scientific bodies have classified R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene). The classifications differ — that's the data.

AgencyYearClassificationNotes
EU F GAS—Exempt from phase-down (GWP<150). Preferred replacement in commercial refrigeration
EPA SNAP—Listed as acceptable substitute in multiple end uses
ASHRAE 34—A2L safety classification
REACH—Registered under EU REACH

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 r-1234ze(e) (trans-1,3,3,3-tetrafluoropropene)

  • Commercial Chillers — Centrifugal and screw chillers for large buildings and data centers
  • Heat Pumps — High-temperature heat pumps for industrial and district heating
  • Foam Blowing — Replacement for HFC-134a and HFC-152a in spray foam insulation
  • Aerosol Propellant — Medical inhalers and consumer aerosols replacing HFC-134a
  • Vending Machines — Self-contained commercial refrigeration

Safer alternatives

Lower-risk approaches that achieve a similar outcome to R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene):

  • R-744 (CO2)
    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×
  • R-717 (Ammonia)
    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 r-1234ze(e) (trans-1,3,3,3-tetrafluoropropene) safe for kids?

Infants are more vulnerable to R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene) 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 r-1234ze(e) (trans-1,3,3,3-tetrafluoropropene)?

R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene) appears in: Centrifugal and screw chillers for large buildings and data centers (Commercial Chillers); High-temperature heat pumps for industrial and district heating (Heat Pumps); Replacement for HFC-134a and HFC-152a in spray foam insulation (Foam Blowing).

What should I do if my child is exposed to r-1234ze(e) (trans-1,3,3,3-tetrafluoropropene)?

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 r-1234ze(e) (trans-1,3,3,3-tetrafluoropropene)?

R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene) has been classified by 4 agencies including EU F GAS, EPA SNAP, ASHRAE 34, REACH, 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 R-1234ze(E) (trans-1,3,3,3-Tetrafluoropropene) in the baby app

Look up products containing r-1234ze(e) (trans-1,3,3,3-tetrafluoropropene), compare to alternatives, and explore the full data record.

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Sources (1)
  1. — expert_curation

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 →