Baby Safety / Compounds / Carboxymethylcellulose (CMC; Sodium CMC; E466)

Is Carboxymethylcellulose (CMC; Sodium CMC; E466) safe for babies and kids?

Moderate risk for kids

Infants are more vulnerable to Carboxymethylcellulose (CMC; Sodium CMC; E466) 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 carboxymethylcellulose (cmc; sodium cmc; e466)?

Also known as: Carboxymethylcellulose sodium salt, Carboxymethylcellulose sodium, Carmellose sodium, Carmethose.

CAS number
9004-32-4
Molecular formula
C8H16NaO8
Molecular weight
263.2 g/mol
SMILES
CC(=O)O.C(C(C(C(C(C=O)O)O)O)O)O.[Na]
PubChem CID
6328154

Risk for babies

Moderate risk

Infants are more vulnerable to Carboxymethylcellulose (CMC; Sodium CMC; E466) 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 Carboxymethylcellulose (CMC; Sodium CMC; E466), 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

3 regulatory and scientific bodies have classified Carboxymethylcellulose (CMC; Sodium CMC; E466). The classifications differ — that's the data.

AgencyYearClassificationNotes
IARC2023Not evaluated by IARC for carcinogenicity — Carboxymethylcellulose (CMC; sodium carboxymethylcellulose; E466; CAS 9004-32-4; semi-synthetic cellulose ether produced by reacting cellulose with chloroacetic acid under alkaline conditions) has no IARC, EPA, or EFSA carcinogenicity classification; however, CMC is among the most scientifically scrutinized food emulsifiers in recent years following publications by Chassaing et al. (2015, Nature; 2022, Cell Host & Microbe) demonstrating that CMC at concentrations achievable in food products disrupts gut microbiota, promotes intestinal inflammation, and increases gut bacterial translocation in mouse models; EFSA 2023 re-evaluation withdrew the previous ADI of 0-25 mg/kg/day and concluded that available data are insufficient to establish a new acceptable daily intake for carboxymethylcellulose; FDA has not issued corresponding restrictions; the compound remains widely used in processed foods at concentrations of 0.1-1.0% (1,000-10,000 mg/kg); the gut microbiome disruption finding represents a potentially significant emerging safety signal warranting continued monitoring
EPA CTX / Genetox—Genotoxicity: positive (Ames: positive, 7 positive / 0 negative reports)
EPA CTX / Genetox—Genotoxicity: positive (Ames: positive, 7 positive / 0 negative reports)

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 carboxymethylcellulose (cmc; sodium cmc; e466)

  • 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 Carboxymethylcellulose (CMC; Sodium CMC; E466):

  • Fragrance-free formulations
    Trade-offs: Consumer preference for scented products
    Relative cost: Lower (ingredient elimination)
  • Essential oil-based fragrances (with disclosure)
    Trade-offs: Natural does not mean safe — many essential oils are skin sensitizers
    Relative cost: 2-5× conventional

Frequently asked questions

Is carboxymethylcellulose (cmc; sodium cmc; e466) safe for kids?

Infants are more vulnerable to Carboxymethylcellulose (CMC; Sodium CMC; E466) 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 carboxymethylcellulose (cmc; sodium cmc; e466)?

Carboxymethylcellulose (CMC; Sodium CMC; E466) 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 carboxymethylcellulose (cmc; sodium cmc; e466)?

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 carboxymethylcellulose (cmc; sodium cmc; e466)?

Carboxymethylcellulose (CMC; Sodium CMC; E466) has been classified by 3 agencies including IARC, EPA CTX / Genetox, EPA CTX / Genetox, 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 Carboxymethylcellulose (CMC; Sodium CMC; E466) in the baby app

Look up products containing carboxymethylcellulose (cmc; sodium cmc; e466), compare to alternatives, and explore the full data record.

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Sources (1)
  1. Carboxymethylcellulose CMC E466 CAS 9004-32-4 Sodium CMC Cellulose Gum DS 0.6-0.95 MW 50k-700k Da; EFSA 2023 ADI Withdrawn Insufficient Data No NOAEL Gut Microbiota; Chassaing 2015 Nature doi:10.1038/nature14232 C57BL/6 Mice 1% Drinking Water 750mg/kg Gut Microbiota Altered Proteobacteria Mucus Penetration Low-Grade Colitis; IL-10-/- Mice Severe Colitis; Germ-Free Mice No Effect Microbiota-Dependent; Chassaing 2022 Cell Host Microbe doi:10.1016/j.chom.2021.12.001 Human Feeding Study n=16 Crossover E. coli Flagellated Proteobacteria; TLR5 TLR4 NF-kB Inflammatory Cascade Mucin Displacement; Ice Cream Ice Crystal Control Cream Cheese Dressings Beverages; Pharmaceutical Tablet Binder Disintegrant Laxative 1.5-6g/day; Prior ADI 0-25 mg/kg/day Withdrawn; FDA GRAS Not Re-Evaluated (2023) — 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 →