2,2',2''-nitrilotriethanol

Endpoint summary

Description of key information

No sensitisation potential was reported in guinea pigs upon dermal sensitisation and challenge. Although allergic reactions to TEA have been reported, the substance is judged to have a very low sensitisation potential.

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

Study period:

19.09-21.10.1988

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

Currently no LLNA study is available for assessment. The Guinea Pig Maximization Test (GPMT) has been carried out as an animal test to predict human sensitization for over a decade and is recommended by international test guidelines such as OECD.

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: sample 838, B 255 A (03.06.1988)
- Purity test date: 14.07.1988

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: 20°C
- Stability under test conditions: in the dark

Species:

guinea pig

Strain:

other: Pirbright-White

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: HOECHST AG, Kastengrund, SPF-Zucht
- Strain: Hoe: DHPK(SPFLac)
- Weight at study initiation: x = 313g (=100 %); xmin= 286g (- 8,6%); * xmax= 337g (+ 7,7%); n = 15
- Housing: 5/ cage
- Diet: ERKA-Mischfutter Nr. 8300 for guinea pigs and rabbits, ad libitum
- Water: Tap water ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3
- Humidity (%): 50 +/- 20- Air changes (per hr):
- Photoperiod (hrs dark / hrs light): 12/12

Route:

intradermal and epicutaneous

Vehicle:

physiological saline

Concentration / amount:

intradermal induction: 2 % dermal induction: unchanged dermal challenge: 10 %

Route:

epicutaneous, open

Vehicle:

physiological saline

Concentration / amount:

intradermal induction: 2 % dermal induction: unchanged dermal challenge: 10 %

No. of animals per dose:

pretest: 6 (determination of the non-irritating concentration determination of the intradermal tolerance: 3 control group 1: 5 control group 2: 5 treatment group: 10

Details on study design:

RANGE FINDING TESTS: (dermal occlusive on the flank skin): 100%, 10% and 1% in salineThe animal's fur was clipped and 0.5 mL of the test substance was applied on a patch that was fixed on the skin under occlusive condition for 24 hours. After 24 hours the patch was removed and the skin was assessed another 24 hours later for erythema and oedema reactions.To study the intradermal tolerance of the test substance, the substance was injected in concentrations of 0.2 %, 1 % and 5 % intradermally in the skin of the back, each concentration at two seperate areas.
MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 2 (intradermal) and 1 epicutaneous- Exposure period: 48 hours (epicutaneous)
- Test groups: 2x 0.1 mL at a concentration of 2 % in 50% Freunds adjuvans; 2x 0.1 mL at a concentration of 2 % in NaCl 0.9 %; 2x 0.1 mL of 50% Freunds adjuvans (intradermal) 0.5 mL of the test substance or vehicle was applied on a 2 x 4 cm patch which was applied for 48 hours to the animal's skin under occlusive conditions
- Control group: 2x 0.1 mL of 50% Freunds adjuvans; 2x 0.1 mL NaCl 0.9 %; 2x 0.1 mL of 50% Freunds adjuvans (intradermal- Site: skin of the back
B. CHALLENGE EXPOSURE
- No. of exposures: 1- Test groups: 0.5 mL of the 10 % test substance or vehicle was applied on a 2 x 2 cm patch which was applied for 24 hours to the animal's skin under occlusive conditions
- Control group: 0.5 mL of the 10 % test substance in saline
- Site: flank skin- Evaluation (hr after challenge): 48 hours, 72 hours

OTHER: Time scale:
day 0: determination of body weight
day 1: intradermal induction
day 9: dermal induction
day 11: evaluation of skin irritation
day 22: dermal challenge
day 23: removal of occlusive dressing
day 24: 1st evaluation
day 25: 2nd evaluation

Scoring:equivalent to Draize scores

Challenge controls:

yes

Positive control substance(s):

not specified

Key result

Reading:

1st reading

Hours after challenge:

48

Group:

test chemical

Dose level:

10 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

none

Key result

Reading:

2nd reading

Hours after challenge:

72

Group:

test chemical

Dose level:

10 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

none

Group:

positive control

Remarks on result:

not measured/tested

Group:

negative control

Remarks on result:

no indication of skin sensitisation

Body weight development:

mean body weight gain:

control group: 30.8 %

Treatment group: 35.7 %

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

The sensitising potential of TEA was investigated in a Guinea Pig Maximisation Test according to OECD TG 406 under GLP conditions (Hoechst, 1988). Based on the results of a pre-test, animals were dermally injected twice with 0.1 mL 2% TEA on day 1, followed by an epicutaneous induction (occlusive) with 0.5 mL undiluted TEA for 48 hours starting on day 9, and a dermal challenge (occlusive) with 0.5 mL 10% TEA for 24 hours on day 22. Dermal reactions were evaluated according to Draize 48 and 72 hours after the start of the dermal challenge. No clinical signs were noticed and all readings were negative.

Regarding the available human data, the positive reactions interpreted as allergic seem to be caused by exposure to TEA in cosmetics and/or topical therapeutic preparations possibly on damaged skin. The diagnosis of TEA contact sensitisation should therefore not be based on a positive patch test reaction alone but on a combination of history and - preferably -validation tests.

The negative experimental findings in animals and the level of exposure to TEA in the population, together with the low frequency of positive reactions to low TEA concentrations in patch-tested patients indicate a very low sensitisation potential in humans, and the risk of sensitisation to TEA on uncompromised skin seems to be very low (Lessmann, 2009).

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Classification, Labeling, and Packaging Regulation (EC) No 1272/2008

The available experimental test data are reliable and suitable for the purpose of classification under Regulation (EC) No 1272/2008.Based on these information the test item is not considered to be classified for skin sensitisation under Regulation (EC) No 1272/2008, as amended for the tenth time in Regulation (EU) No 2017/776.