Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
the study does not need to be conducted because the substance is classified as corrosive to the skin
Cross-reference
Reason / purpose:
data waiving: supporting information
Reference
Based on the results from the in vitro and read across in vivo irritation studies, the test substance  is considered to be corrosive to skin as well as eyes.
Endpoint conclusion:
adverse effect observed (corrosive)
Endpoint conclusion:
no study available
Endpoint conclusion:
no study available

Skin

Study 1: Anin vitrotranscutaneous electrical resistance (TER) assay was conducted to assess the skin corrosivity potential of the test substance, C16-18 TMAC (50% active ingredient) using skin discs obtained from the pelts of humanely killed young Crl (WI) BR Wistar rats. The test substance was applied to the epidermal surface of three skin discs per contact period, 1, 4, and 24 hours. At the end of the contact period the test substance was removed using a jet of warm tap water. Corrosive substances are found to produce an irreversible loss of normal stratum corneum integrity and function, which can be measured as a reduction in the inherent TER. A threshold value of 5 kΩ has been established below which substances are considered likely to be corrosivein vivo. The mean electrical resistance measured using low voltage alternating current electronic databridge after 1, 4 and 24 hours was 7, 2.6 and 2.2 kΩ. Under the study conditions, the test substance was considered to have the potential to be corrosive to skin (Sanders, 2002).

Study 2: A study was conducted to determine the skin irritation potential of the test substance, C16 -18 and C18 -unsatd. TMAC (50% active) in rabbits, according to a method similar to OECD Guideline 204. Six rabbits (both sexes) were treated with 0.5 mL of undiluted test substance (50% active ingredient) in an occlusive patch fixed with adhesive tape and wrapped with an impervious material, for 4 h. Observations were made at 4 h, 48 h and 10 days post-exposure. If the test substance appeared to be corrosive after 4 h, another study was conducted with a 1 h exposure period under similar test conditions. The Draize scoring criteria was used for evaluating the corrosion potential. At 4 h, very slight to well-defined erythema, very slight ischemia and very slight oedema were observed, with an average irritation score of 4/8. At 48 h, there was well-defined to moderate erythema, very slight to slight ischemia and very slight or slight oedema and the average irritation score was 5.4/8. After 10 days, slight to distinct incrustation and decreased hair growth was observed. After an exposure period of 1 h, very slight erythema was observed with an average irritation score of 0.85/8. After 48 h, there was very slight to moderate erythema and very slight or slight oedema and the average irritation score was 1.25/8. No skin effects were observed after 10 days. Under the study conditions, the undiluted test substance (50% active ingredient) was corrosive after 4 h of occlusive exposure.

Eye

In accordance with Annex VII, Section 8.2, Column 2, eye irritation studydoes not need to be conducted because the substance is classified as corrosive to the skin (Category 1C).


Based on the available results from in vitro and in vivo read across studies, the test substance warrants a corrosive, 'Skin Corr. 1C; H314: Causes severe skin burns and eye damage' as well as serious eye damage, 'Eye dam. 1; H31: Causes serious eye damage' classification according to the EU CLP criteria (Regulation EC 1272/2008). Labelling for this endpoint is covered by the above classifications for skin effects.

Data source

Materials and methods

Results and discussion

Applicant's summary and conclusion