Body & Beauty / Compounds / HEDP (Etidronic acid / 1-Hydroxyethylidene-1,1-diphosphonic acid / E1100ii)

HEDP (Etidronic acid / 1-Hydroxyethylidene-1,1-diphosphonic acid / E1100ii) on your skin: a safety profile

Low risk

(People-specific data is limited; this page draws from human adult context.) HEDP (Etidronic acid / 1-Hydroxyethylidene-1,1-diphosphonic acid / E1100ii) poses low risk to adults under normal use conditions.

What is hedp (etidronic acid / 1-hydroxyethylidene-1,1-diphosphonic acid / e1100ii)?

The IUPAC name is 2-ethoxybenzamide.

Also known as: 2-ETHOXYBENZAMIDE, ethenzamide, 938-73-8, o-Ethoxybenzamide.

IUPAC name
2-ethoxybenzamide
CAS number
2809-21-4
Molecular formula
C9H11NO2
Molecular weight
165.19 g/mol
SMILES
CCOC1=CC=CC=C1C(=O)N
PubChem CID
3282

Risk for people

Low risk

HEDP (Etidronic acid / 1-Hydroxyethylidene-1,1-diphosphonic acid / E1100ii) poses low risk to adults under normal use conditions.

Regulatory consensus

3 regulatory and scientific bodies have classified HEDP (Etidronic acid / 1-Hydroxyethylidene-1,1-diphosphonic acid / E1100ii). The classifications differ — that's the data.

AgencyYearClassificationNotes
EU—Annex III cosmetic ingredient; max 1.5% in hair products
ECHA—H302 harmful if swallowed; H314 severe skin burns/eye damage (concentrated)
FDA—Indirect food additive

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 you encounter hedp (etidronic acid / 1-hydroxyethylidene-1,1-diphosphonic acid / e1100ii)

  • Cleaning Products — bathroom cleaners, toilet bowl cleaners, rust removers, dishwasher detergent
  • Personal Care — hair dye stabilizer, hair bleach peroxide stabilizer
  • Water Treatment — cooling tower scale inhibitor, boiler water treatment, RO membrane antiscalant
  • Food Processing — E1100ii — sugar refining process aid

Safer alternatives

Lower-risk approaches that achieve a similar outcome to HEDP (Etidronic acid / 1-Hydroxyethylidene-1,1-diphosphonic acid / E1100ii):

  • Phosphino-carboxylic acid polymers
    Trade-offs: Requires R&D investment to redesign synthesis routes; may reduce yield or throughput initially; long-term benefits include reduced waste treatment costs, regulatory compliance, and worker safety; 12 Principles of Green Chemistry framework available.
  • Polyaspartic acid
    Trade-offs: Alternative chelating agent; stability constants for target metal ions differ; biodegradability varies (EDTA poorly biodegradable, citrate fully biodegradable); downstream water treatment impact should be assessed.

Frequently asked questions

What products contain hedp (etidronic acid / 1-hydroxyethylidene-1,1-diphosphonic acid / e1100ii)?

HEDP (Etidronic acid / 1-Hydroxyethylidene-1,1-diphosphonic acid / E1100ii) appears in: bathroom cleaners (cleaning products); toilet bowl cleaners (cleaning products); hair dye stabilizer (personal care); hair bleach peroxide stabilizer (personal care); cooling tower scale inhibitor (water treatment).

Why do regulators disagree about hedp (etidronic acid / 1-hydroxyethylidene-1,1-diphosphonic acid / e1100ii)?

HEDP (Etidronic acid / 1-Hydroxyethylidene-1,1-diphosphonic acid / E1100ii) has been classified by 3 agencies including EU, ECHA, FDA, 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 HEDP (Etidronic acid / 1-Hydroxyethylidene-1,1-diphosphonic acid / E1100ii) in the body app

Look up products containing hedp (etidronic acid / 1-hydroxyethylidene-1,1-diphosphonic acid / e1100ii), compare to alternatives, and explore the full data record.

Open in body View raw API data

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 →