tert-butyl bromoacetate

Endpoint summary

Description of key information

Corrosive to the skin.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From June 05th to 19th, 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

adopted on 17th,07,1992

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: David Percival Ltd, Sandbach UK
- Age at study initiation: from 12 to 16 weeks old.
- Weight at study initiation: from 2.0 to 3.5 kg.
- Housing: individually in suspended metal cages.
- Diet:STANRAB SQC rabbit diet.
- Water: free access to tap water.
- Acclimation period: at least 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature: 17 - 23 °C
- Humidity: 30 - 70 %
- Air changes: at least 15 ACH
- Photoperiod: 12 hours dark

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 ml
- pH: the pH of the undiluted test material was determined prior to commencement of the study and was found to be 7.3.

Duration of treatment / exposure:

4 hours

Observation period:

1, 24, 48 and 72 hours after patches removal.
Additional observation made on day 7 to assess the reversibility.

Number of animals:

3 males

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm cotton gauze treated with test material.
- Type of wrap if used: elasticated corset.

REMOVAL OF TEST SUBSTANCE
- Washing: swabbing with cotton wool soaked with 74 % methylated spirits.
- Time after start of exposure: 4 hours

SCORING SYSTEM
Erythema and eschar formation
No erythema...................................................0
Very slight erythema (barely perceptible)......1
Well-defined erythema....................................2
Moderate to severe erythema.........................3
Severe erythema to slight eschar formation...4

Oedema formation
No oedema..............................................................................................................0
Very slight oedema (barely perceptible).................................................................1
Slight oedema (edges well-defined)........................................................................2
Moderate oedema (raised ca. 1 mm).......................................................................3
Severe oedema (raised more than 1 mm; extending beyond area of exposure)....4

Irritation parameter:

erythema score

Basis:

animal: 3/3

Time point:

24/48/72 h

Score:

4

Reversibility:

not reversible

Irritation parameter:

edema score

Basis:

animal: 3/3

Time point:

24/48/72 h

Score:

3.33

Reversibility:

not reversible

Irritant / corrosive response data:

Severe erythema and severe oedema were noted on all animals 1 and 24 hours after patch removal, with severe erythema and moderate oedema at 48 and 72 hours. Well-defined erythema extended approximately 5 cm beyond the treatment sites of all animals one hour after patch removal and at 24, 48 and 72 hours observation.
Dermal haemorrhage, resempbling a purble/black colored bruise, was noted at all treated skin sites one hour after removal and at the 24, 48 and 72 hours.
A hardened dark brown colored scab, undulating in appearance and preventing evaluation of erythema and oedema, was noted on all animals at the 7 day observation.

The reactions noted at all treated skin sites were indicative of dermal corrosion. All animals were killed for humane reasons immediately after the 7-day observation in accordanco with current UK Home Office guideline.

Calculation for CLP classification

Observation time	Rabbit no. 1		Rabbit no. 2		Rabbit no. 3
	Erythema	Oedema	Erythema	Oedema	Erythema	Oedema
24 h	4	4	4	4	4	4
48 h	4	3	4	3	4	3
72 h	4	3	4	3	4	3
Mean value	4	3.33	4	3.33	4	3.33

Individual skin reactions

Rabbit no.	Time after exposure
	1 hour		24 hours		48 hours		72 hours		7 days
	Erythema/eschar	Oedema	Erythema/eschar	Oedema	Erythema/eschar	Oedema	Erythema/eschar	Oedema	Erythema/eschar	Oedema
1	4 HdR	4	4 HdRLe	4 Oe	4 HdRLeLF	3 Oe	4 HdRLeLF	3	? eStSwK	? od
2	4 HdR	4	4 HdRLe	4 Oe	4 HdRLeLF	3 Oe	4 HdRLeLF	3	? eStSwK	? od
3	4 HdR	4	4 HdRLe	4 Oe	4 HdRLeLF	3 Oe	4 HdRLeLF	3	? eStSwK	? od

Hd = dermal haemorrhage resembling a purple/black colored bruise

R = well-defined erythema

Oe = severe oedema

Le = loss of skin elasticity

Lf = loss of skin flexibility

St = hardened dark brown/black colored scab

Sw ? scab ondulating

?e = adverse reactions prevented evaluation of erythema

?od = adverse reactions prevented evaluation of oedema

K = animal humanely killed immediately after observation

Interpretation of results:

other: Skin Corr. 1B (H314), according to the CLP Regulation (EC 1272/2008)

Conclusions:

Skin corrosive, Subcategory 1B.

Executive summary:

The test was performed according to OECD 404 (1992). Three New Zeland White rabbit were treated with a single 4 -hours semi-occluded application of test material. Reactions were scored at 1, 24, 48 and 72 hours after patches removal. Additional observation made on day 7 to assess the reversibility.

Severe erythema and severe oedema were noted on all treated animals after 4 hours of patch removal.

Conclusion

The substance is classified as Skin Corr. 1B.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (corrosive)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

SKIN IRRITATION

The skin irritation potential was tested according to OECD 404 (1992). Three New Zeland White rabbit were treated with a single 4 -hours semi-occluded application of test material. Severe erythema and severe oedema were noted on all animals 1 and 24 hours after patch removal, with severe erythema and moderate oedema at 48 and 72 hours. Well-defined erythema extended approximately 5 cm beyond the treatment sites of all animals one hour after patch removal and at 24, 48 and 72 hours observation. Dermal haemorrhage, resempbling a purble/black colored bruise, was noted at all treated skin sites one hour after removal and at the 24, 48 and 72 hours. A hardened dark brown colored scab, undulating in appearance and preventing evaluation of erythema and oedema, was noted on all animals at the 7 day observation.

The reactions noted at all treated skin sites were indicative of dermal corrosion. All animals were killed for humane reasons immediately after the 7-day observation in accordanco with current UK Home Office guideline.

Therefore, the substance is classified as skin corrosive, subcategory 1B, according to the CLP Regulation (EC 1272/2008).

EYE IRRITATION

Regarding the eye ittiration potential, no tests have been performed because of the substance resulted to be skin corrosive, so it is considered able to causes severe skin burns and eye damage.

Justification for classification or non-classification

The substance caused irreversible severe effects on the skin of tested rabbits, therefore the substance does meet the criteria for classification under the Regulation EC 1272/2008 (CLP) as Skin Corr. 1B.