ColaLiquids DC5, DL, DM (Commercial names)Cocamide DIPA (INCI name)

Endpoint summary

Description of key information

The CIR review in 1986 of four cosmetic ingredients (Cocamide DEA, Lauramide DEA, Linoleamide DEA, and Oleamide DEA) concluded that 'generally, these products were mild skin irritants but not sensitizers or photosensitizers.'

Further assessment of cocamide DEA was carried out by the same panel in 1996 (Journul of the American College of Toxicology

15(6):527-542, 1996 Cosmetic Ingredient Review). Clarification of the original conclusion is based on the results of a skin irritation test in which 15 volunteers were tested with a surfactant solution containing 10% Cocamide DEA, the highest concentration tested in predictive patch tests.

On the basis of the animal and clinical data presented in the present report, the Expert Panel concluded that Cocamide DEA is safe as used in rinse-off products and safe at concentrations ~10% in leave-on cosmetic products.

(Cocamide DEA (Amides, coco, N,N-bis(hydroxyethyl) is the ethanol derivative rather than the propionate equivalent, which is the substance under review. It is essentially the same structural formula with an ethyl group instead of a propyl group and as such is assessed as being a good surrogate substance for read-across in the absence of actual oral toxicity data on the substance itself.)

It is not thought necessary to advise that further testing should be carried out since the level at which this substance is used in commercially available products (shampoos etc) is ca. 3%, well below the 10% that the CIR panel advused as being the safe limit.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Qualifier:

equivalent or similar to guideline

Guideline:

other: Repeat insult patch testing but In-use study

Deviations:

not applicable

Principles of method if other than guideline:

One hundred four women participated in an in-use study to determine the safety and efficacy of a shampoo containing 2% Cocamide DEA. Each panelist was patch tested on the upper arm with 2% aqueous shampoo, containnig other typical shampoo ingredients (preservative 15ppm and fragrance 5% in oil). The three occlusive patches were applied and scored for irritation 48 h later at the time of patch removal.
The subjects were then instructed to shampoo daily with the test product for 87 days.
Ten days after the final use of the shampoo, challenge patches were administered following the same procedure as the initial patches except the preservative concentration was increased to 50 ppm
and an additional scoring for reactions was made 24 h after patch removal. No reactions were observed to the preservative or fragrance patches.
Eleven subjects reacted to the 2% shampoo initial patch; eight had mild erythema (l+scores on a O-4 scale), one had intense erythema (2+), and two subjects had erythema and edema (3+). Twenty-four subjects had irritation scores of 1 + (18/24), 2+ (3/24), and 3+ (3/24) 48 h after challenge patch application of the shampoo. Thirty subjects had 1 + (25/30) or 2 + (5/30) irritation scores at the second
challenge reading.
All reactions were considered to be irritant in nature. The shampoo was an irritant but not a sensitizer.

GLP compliance:

not specified

Remarks:

data taken from a CIR review paper. Full details are not disclosed and the test was 1983 so GLP not necessarily required at that time.

Type of study:

patch test

Justification for non-LLNA method:

Because adequate data from an in vivo skin sensitisation study are available.

Specific details on test material used for the study:

2% patched as 2% aqueous solution, used full strength for 87 days

Species:

other: human

Sex:

female

Key result

Reading:

other: observations on human use

Hours after challenge:

240

Group:

test chemical

Dose level:

2%

No. with + reactions:

11

Total no. in group:

104

Clinical observations:

Eleven subjects reacted to the 2% shampoo initial patch; eight had mild erythema (l+ scores on a O-4 scale), one had intense erythema (2+), and two subjects had erythema and edema (3+). All reactions were considered to be irritant in nature

Remarks on result:

no indication of skin sensitisation

Interpretation of results:

GHS criteria not met

Conclusions:

On the basis of the animal and clinical data assessed, the CIR Expert Panel concluded that Cocamide DEA is safe as used in rinse-off products and safe at concentrations ~10% in leave-on cosmetic products. Cocamide DEA should not be used as an ingredient in cosmetic products in which N-nitroso compounds are formed.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)