Reaction mass of 4,4'-isopropylidenediphenol and phenol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

Principles of method if other than guideline:

Lymph node stimulation was measured by cell counts instead of radioactive labelling, as authorised in OECD Guideline No. 429.

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

4,4'-isopropylidenediphenol

EC Number:

201-245-8

EC Name:

4,4'-isopropylidenediphenol

Cas Number:

80-05-7

Molecular formula:

C15H16O2

IUPAC Name:

2,2-bis(4-hydroxyphenyl)propane

Details on test material:

Solid white powder, 99.36 % pure.

In vivo test system

Test animals

Species:

mouse

Strain:

NMRI

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Animal strain: Specific pathogen-free female NMRI mice of the strain Hsd Win:NMRI were obtained from Harlan Winkelmann GmbH, 33176 Borchen, Germany.
- Housing: During the adaptation period, animals were housed in conventional Makrolon type III cages with up to 10 mice per cage. During the study period, animals were housed in type II cages with one mouse per cage. The cages were changed at least twice a week. Low-dust wood granulate type S 8/15 from J. Rettenmaier & Sohne Fullstoff-Fabriken, 7092 Ellwangen-Holzmuhle, was used as bedding. The wood granulate was analysed at random for contaminants.
-Diet: Ad libitum. Feed was PROVIMI KLIBA SA 3883 maintenance diet for rats and mice (from Provimi Kliba SA, CH-4303 Kaiseraugst, Switzerland). Contaminant content and nutritive composition was analysed routinely in random samples.
-Drinking water. Ad libitum. Tap water of drinking water quality was provided in polycarbonate bottles.
-Acclimation period: At least 7 days, during which the state of health of the animals was monitored.

ENVIRONMENTAL CONDITIONS
-Temperature: 20-24 degrees C
-Relative humidity: About 30%
-Photoperiod: 12 hours light/12 hours dark

Study design: in vivo (LLNA)

Vehicle:

other: DAE 433

Concentration:

25 µl of a 0%, 3%, 10%, or 30% solution of BPA in DAE 433

No. of animals per dose:

6

Details on study design:

Female NMRI mice were treated epicutaneously on the dorsal part of both ears with 25 µl per ear of a solution containing 0%, 3%, 10%, or 30% BPA in DAE 433 (6 animals per dose group). Treatments were given once per day for three consecutive days (day 0, day 1, and day 2). On day 0 and day 3 (one day after last application), the ear swelling of the animals was measured using a spring-loaded micrometer and mean ear swelling was calculated. Ear weight was measured on day 3 using a punch to cut off a piece of each ear with an 8 mm diameter. Also on day 3, animals were sacrificed by inhalation of carbon dioxide and lymphatic organs (the auricular lymph nodes) were transferred to PBS. Lymph nodes (LNs) were weighed and then crushed through a plastic sieve into 12-well plates and cell counts per ml were determined using a Coulter counter. The stimulation index was calculated by dividing the absolute number of the weight or cell counts of the treated lymph nodes by the vehicle lymph nodes.

Statistics:

When statistically reasonable, the values from treated groups were compared with those from controls by the Mann-Whitney or the Wilcoxon significance test (Rank Sum Test or One-Way ANOVA or Kruskal-Wallis ANOVA) at significance levels of 5% (one-tailed for LLNA/ear swelling). Outlying values in the LN/ear weights or LN cell counts were eliminated at a probability level of 99% by Nalimov's method. For the LLNA/ear swelling, the smallest significant differences in the means were calculated by Scheffe's method. For indices, only the standard deviations between groups and difference analysis of the mean values (Scheffe's method) were used in the evaluation of the biological relevance.

Results and discussion

Positive control results:

No positive control was used.

In vivo (LLNA)

Results

Results 1

Parameter:

other: Lymph node weight index

Value:

0.85

Test group / Remarks:

3%

Results 2

Parameter:

other: Lymph node weight index

Value:

1.07

Test group / Remarks:

10%

Results 3

Parameter:

other: Lymph node weight index

Value:

0.93

Test group / Remarks:

30%

Results 4

Parameter:

other: ear swelling index

Value:

1.02

Test group / Remarks:

3%

Results 5

Parameter:

other: ear swelling index

Value:

1.04

Test group / Remarks:

10%

Results 6

Parameter:

other: ear swelling index

Value:

0.95

Test group / Remarks:

30%

Results 7

Parameter:

SI

Remarks:

cell count index

Value:

1.25

Test group / Remarks:

3%

Results 8

Parameter:

SI

Remarks:

cell sount index

Value:

1.35

Test group / Remarks:

10%

Results 9

Parameter:

SI

Remarks:

cell count index

Value:

1.24

Test group / Remarks:

30%

Any other information on results incl. tables

The authors stated that compared to vehicle-treated animals, none of the measured parameters reached or exceeded the "positive levels" defined for the assay.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The authors concluded that BPA has neither an irritating nor a sensitising potential in mice after dermal application.

Executive summary:

Female NMRI mice were treated epicutaneously on the dorsal part of both ears with 25 µl per ear of a solution containing 0%, 3%, 10%, or 30% BPA in DAE 433 (6 animals per dose group). Treatments were given once per day for three consecutive days (day 0, day 1, and day 2). On day 0 and day 3 (one day after last application), the ear swelling of the animals was measured using a spring-loaded micrometer and mean ear swelling was calculated. Ear weight was measured on day 3 using a punch to cut off a piece of each ear with an 8 mm diameter. Also on day 3, animals were sacrificed by inhalation of carbon dioxide and lymphatic organs (the auricular lymph nodes) were transferred to PBS. Lymph nodes (LNs) were weighed and then crushed through a plastic sieve into 12-well plates and cell counts per ml were determined using a Coulter counter. The stimulation index was calculated by dividing the absolute number of the weight or cell counts of the treated lymph nodes by the vehicle lymph nodes. Compared to vehicle-treated animals, none of the measured parameters reached or exceeded the "positive levels" defined for the assay. The authors concluded that BPA has neither an irritating nor a sensitising potential in mice after dermal application.