Cocamidopropyl betaine (CAPB) is an amphoteric surfactant. The particular behaviour of amphoterics is related to their zwitterionic character; that means: both anionic and cationic structures are found in one molecule. Cocamidopropyl betaine is a high production volume chemical represented by the CAS Nos. 61789-40-0 and 70851-07-9. All relevant physicochemical, toxicological and ecotoxicological data, so far available (April 2005), are included in this document.
The usage of cocamidopropyl betaine in personal-care products has grown in recent years due to its relative mildness compared with other surface active compounds. In Western Europe 59000 metric tons cocamidopropyl betaines were produced in the year 2002 and they are predominately used as a cosmetic ingredient (50 % of the produced volume), such as shampoos, and as a detergent (50 % of the produced volume), such as hand washing agents. The concentration of cocamidopropyl betaine in cleaning and personal care products ranges up to 30% active matter.
The environmental risk assessment will be published in a single comprehensive document on a later date at www.heraproject.com.
Human health assessment
With dermal and oral LD50 values of > 2000 and e 4900 mg/kg bw, respectively, the acute toxicity of cocamidopropyl betaine is very low. About 30% active formulations are irritating to the skin and the eyes, while d 10 % active solutions caused only mild skin and eye reactions. From subacute and subchronic studies with rats a NOAEL of 1000 mg/kg bw/day for systemic toxicity of the 30% active CAPB was derived. Cocamidopropyl betaine gave no indication for genotoxic or teratogenic effects. Contact allergy to CAPB has been reported although extensive data now suggests that impurities in the final product are responsible for causing this skin sensitization.
Relevant consumer scenarios were described for the usage of household detergent products containing cocamidopropyl betaine and the resulting Margin of Exposures (MOE) were calculated comparing the systemic NOAEL to the estimated exposure values. For each scenario the MOE was above 104 (with the exception of one, which had a MOE of 7700 pre-treatment of clothes), which represents a very high safety margin. Also the estimation of the total consumer exposure resulted in a MOE of about 2800 which is also a high value. No risk is calculated for potential uptake via drinking water or food.
Acute toxic effects after unintentional oral exposure of a few millilitres of the formulations (1 30% concentration) are not to be expected.
Neat CAPB is an irritant to skin and eyes. The irritation potential of aqueous solutions of CAPB depends on concentration. Local effects of hand wash solutions containing CAPB do not cause concern given that the concentrations of CAPB in such solutions are well below 1% and therefore not expected to be irritating to eye or skin. Laundry pre-treatment tasks, which may translate into brief hand skin contact with higher concentrations of CAPB, may occasionally result in mild irritation easily avoided by prompt rinsing of the hands in water. Potential irritation of the respiratory tract is not a concern given the very low levels of airborne CAPB generated as a consequence of cleaning sprays aerosols. Immediate eye rinsing with water for several minutes is recommended after accidental splashing of CAPB solutions, as eye irritation reactions may occur.
In view of the available database on toxic effects, the low exposure values calculated and the resulting large Margin of Exposure described above, it can be concluded that use of CAPB in household laundry and cleaning products raises no safety concerns for the consumers.