(3-fluoro-4'-propyl[biphenyl]-4-yl)boronic acid

Endpoint summary

Description of key information

A LLNA study according to OECD Guideline 429 under GLP conditions was conducted with a structural analogue substance. The structural analogue did not show any sensitizing potential to skin. Thus, the test item is not considered to be a skin sensitizer.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Reference 1

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2007-05-15 to 2007-05-30

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Version / remarks:

04-2002

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

Strain:

CBA

Remarks:

CBA/CaOlaHsd

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Netherlands B.V., NL 5960 AD Horst
- Age: 7-8 weeks at beginning of acclimatisation
- Weight at study initiation: 17.4 - 20 g
- Housing: single in Makrolon type-1 cages
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: not further specified

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3
- Humidity (%): 30-88
- Photoperiod (hrs dark / hrs light): 12 / 12

IN-LIFE DATES: Days 1 - 5

Vehicle:

dimethylformamide

Concentration:

pre test for signs of irritation: 2.5, 5, 10 and 25 %
main test: 5, 10 and 25 %

No. of animals per dose:

pre test: 2 f
main test: 5 f per group (3 test groups, 1 control group)

Details on study design:

RANGE FINDING TESTS
To determine the highest non-irritant test concentration or the highest technically applicable concentration, a pretest was performed in two mice with test item concentrations of 2.5, 5, 10 and 25 % on one ear each. No irritation effects were observed at these concentrations after a single application.

MAIN STUDY
Criteria used to consider a positive response: 3-fold greater response at one concentration in SI than control animals

TREATMENT PREPARATION AND ADMINISTRATION
Each test group of mice was treated by topical (epidermal) application to the dorsal surface of each ear lobe (left and right) with different test item concentrations of 5, 10 and 25% (w/v) in dimethylformamide. The application volume of 25 uL was spread over the entire dorsal surface (0 - 8 mm) of each ear lobe once daily for three consecutive days. A further group of mice was treated with an equivalent volume of the relevant vehicle alone (control animals).
Five days after the first topical application, all mice were administered with 250 uL of 78.8 uCi/mL 3H-methyl thymidine (3HTdR) by intravenous injection via a tail vein. Prior to the first application of the test item and prior to treatment with 3HTdR the ear thickness was determined using a micrometre.
The level of 3HTdR incorporation was then measured on a ß-scintillation counter. Similarly, background 3HTdR levels were also measured in two 1 mL-aliquots of 5 % trichloroacetic acid. The ß-scintillation counter expresses 3HTdR incorporation as the number of radioactive disintegrations per minute (DPM).
The validation/positive control experiment was performed with alpha-Hexylcinnamaldehyde in acetone:olive oil (4+1) in mice.

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Statistics:

Mean values and standard deviations were calculated in the body weight tables. A statistical analysis was conducted for assessment of the dose-response relationship, and the EC3 value was calculated according to the equation EC3 = (a-c) [(3-d)/(b-d)] + c, where EC3 is the estimated concentration of the test item required to produce a 3-fold
increase in draining lymph node cell proliferative activity; (a, b) and (c, d) are respectively the co-ordinates of the two pair of data lying immediately above and below the S.I. value of 3 on the local lymph node assay dose response plot.

Positive control results:

Conc. (%, w/v) SI
5 1.03
10 1.59
25 1.68

Key result

Parameter:

SI

Value:

1.03

Test group / Remarks:

5%

Key result

Parameter:

SI

Value:

1.59

Test group / Remarks:

10%

Key result

Parameter:

SI

Value:

1.68

Test group / Remarks:

25%

Key result

Parameter:

EC3

Remarks:

% (w/v)

Remarks on result:

not determinable

Remarks:

All SI were < 3

Interpretation of results:

GHS criteria not met

Conclusions:

The test item was not a skin sensitiser in this assay.

Reference 2

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

For this endpoint information from structural similar compounds is available. The studies for these similar compounds were performed according to GLP and the methods applied are fully compliant with OECD TG 429. See chapter 13 report for a more detailed justification.

Reason / purpose for cross-reference:

read-across source

Key result

Parameter:

SI

Value:

1.03

Test group / Remarks:

5 %

Key result

Parameter:

SI

Value:

1.59

Test group / Remarks:

10 %

Key result

Parameter:

SI

Value:

1.68

Test group / Remarks:

25 %

Key result

Parameter:

EC3

Remarks on result:

not determinable

Remarks:

All SI were < 3

Interpretation of results:

GHS criteria not met

Reference 3

Endpoint:

skin sensitisation: in vitro

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

an in vitro skin sensitisation study does not need to be conducted because adequate data from an in vivo skin sensitisation study are available

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Based on the data provided, the test item is not classified and labelled for Skin Sensitization according to Regulation (EC) No 1272/2008.