Benzene-1,2:4,5-tetracarboxylic dianhydride

Endpoint summary

Description of key information

Skin sensitization (LLNA)

The study was performed in accordance with OECD-guideline no. 429 and EU-test method B.42. The Stimulation Index ranged from 8.62 to 9.12 for the three dose groups. In conclusion, the test material was considered to be a sensitiser under the conditions of the test.

Respiratory sensitization

Two respiratory sensitization studies are reported in the literature and submitted as supporting studies:

Study 1: Based on the results of this study, it is believed that PMDA could cause respiratory sensitization if the exposure concentration was higher and/or of a longer duration.

Study 2: Based on the results of this study, PMDA induces respiratory sensitization in the rat. There exists cross-sensitization reaction between PMDA and TMA, and the response appeared to be stronger when PMDA-exposed rats were challenged with a single exposure to TMA.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

June 2009

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)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Specific details on test material used for the study:

- Sponsor's identification: LZ6119
- Description: white powder
- Batch number: CSA 0901038
- Purity: >= 99.5% w/w
- Date received: 01 May 2009
- Storage conditions: room temperature in the dark

Species:

mouse

Strain:

CBA/Ca

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK, Limited, Bicester, Oxon, UK.
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 12 weeks
- Weight at study initiation: 15-23 g
- Housing: individual housing
- Diet (e.g. ad libitum): 2014 Teklad Global Rodent diet supplied by Harlan Teklad, Blackthorn, Bicester, Oxon, UK
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 5 days
- Indication of any skin lesions: no

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-25°C
- Humidity (%): 30-70%
- Air changes (per hr): 15 changes/hr
- Photoperiod (hrs dark / hrs light): 12 hrs continuous light (06.00 to 18.00) and twelve hrs darkness

Vehicle:

dimethylformamide

Concentration:

Groups of four mice were treated with the test material at concentrations of 25%, 10% or 5% w/w in dimethyl formamide. The preliminary screening test suggested that the test material would not produce systemic toxicity or excessive local irritation at the highest suitable concentration. A further group of four mice received the vehicle alone in the same manner.

No. of animals per dose:

Groups of four mice were treated with the test material at concentrations of 25%, 10% or 5% w/w. A further group of four mice received the vehicle alone in the same manner.

Details on study design:

The mice were treated by daily application of 25 ul of the appropriate concentration of the test material to the dorsal surface of each ear for three consecutive days (Days 1, 2, 3). The test material formulation was administered using an automatic micropipette and spread over the dorsal surface of the ear using the tip of the pipette.

Positive control substance(s):

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

Statistics:

None

Positive control results:

Methods:
A group of five animals was treated with 50 ul (25 ul per ear) of alpha-Hexylcinnamaldehyde as a solution in dimethylformamide at a concentration of 15% v/v. A further control group of five animals was treated with dimethyl formamide alone.

Results:
The Stimulation Index expressed as the mean radioactive incorporation for each treatment group divided by the mean radioactive incorporation of the vehicle control group are as follows:
- Concentration (% v/v) in DMF: 15%
- Stimulation Index: 4.24
- Result: 4.24

Conclusion:
alpha-Hexylcinnamaldehyde was considered to be a sensitiser under the conditions of the test

Key result

Parameter:

SI

Value:

9.12

Test group / Remarks:

Test item concentration 5%

Key result

Parameter:

SI

Value:

8.62

Test group / Remarks:

Test item concentration 10%

Key result

Parameter:

SI

Value:

9

Test group / Remarks:

Test item concentration 25%

Cellular proliferation data / Observations:

CLINICAL OBSERVATIONS:
There were no deaths. No signs of systemic toxicity were noted in the test or control animals during the test. White residual test material on the ears was noted post dose on Days 1 to 3 in animals treated with the test material at a concentration of 25% w/w in dimethyl formamide.

BODY WEIGHTS:
Body weight changes of the test animals between Day 1 and Day 6 were comparable to those observed in the corresponding control group animals over the same period.

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

The test material was considered to be a sensitiser under the conditions of this LLNA-study.

Executive summary:

A study was performed to assess the skin sensitisation potential of the test material in the CBA/Ca strain mouse following topical application to the dorsal surface of the ear. The method was performed in accordance with OECD-guideline no. 429 and EU-test method B.42. Following a preliminary screening test in which no clinical signs of toxicity were noted at a concentration of 25% w/w, this concentration was selected as the highest dose investigated in the main test of the Local Lymph Node Assay. Three groups, each of four animals, were treated with the test materialcas a solution in dimethylformamide (DMF) at concentrations of 25%, 10% or 5% w/w. A further group of four animals was treated with DMF alone. The Stimulation Index ranged from 8.62 to 9.12 for the three dose groups. In conclusion, the test material was considered to be a sensitiser under the conditions of the test.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Respiratory sensitisation

Link to relevant study records

Reference

Reference 1

Endpoint:

respiratory sensitisation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

July-August 1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

no guideline available

GLP compliance:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Lot/batch No.of test material: identification no. 10820-33-D
- Expiration date of the lot/batch: no data

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature (approximately 20°C)
- Stability under test conditions: stable

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories. Inc., Portage. MI, USA
- Age at study initiation: 6 weeks
- Weight at study initiation: ca. 270-430 g
- Housing: gang housing
- Diet (e.g. ad libitum): Purina Rodent Chow 5001, Ralston Purina Co., St. Louis. MO, USA
- Water (e.g. ad libitum): supplied from a reverse-osmosis (RO) purifier by an automatic watering system
- Acclimation period: 2-week quarantine period
- Fasting period: 18 hours
- Indication of any skin lesions: no

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22°C
- Humidity (%): 40%
- Photoperiod (hrs dark / hrs light): 12 hours fluorescent lighting, 12 hours darkness

Route of induction exposure:

inhalation

Route of challenge exposure:

inhalation

Vehicle:

unchanged (no vehicle)

Concentration:

Induction and challenege exposure: 50 microgr/m3 of test article aerosol in air

No. of animals per dose:

10 rats/sex/group

Details on study design:

Following a 2-week quarantine period. three groups of rats (10 rats/sex/group = 60 total rats) were randomly selected from a pool of rats whose body weigllts did not deviate more than three standard deviation units from the population mean. One group was exposed to 50 ug/m3 of the test article aerosol in air and two groups were exposed in a cbamber to clean filtered air only. The duration of the exposures was 6 hours per day for 5 days.
Following a 3-week rest, the test article-exposed rats along with one filtered air control (F AC) group were cbal1eDged with 50 ug/m3 of test item for 6 hours. The third group of rats was designated as nonchallenged filtered air controL All rats were euthanized and necropsied approximately 18 hours after the final exposure.

Challenge controls:

None

Positive control substance(s):

none

Negative control substance(s):

none

Results:

The time-weighted average concentrations of the test item for the five exposures and one challenge were 56.5 and 48.6 ug/m3, respectively. No significant clinical signs were observed in any rat during the study. There were no statistically significant effects of treatment on body weight. lung foci or absolute and relative lung weight and volume. Serum IgG antibody levels_were significantly elevated in the PMDA-exposed male rats only. When antibody values for the males and females were combined, these values were also statistically significant from controls. The three test item exposed males which had the highest number of lung foci (i.e. 14, 20 and 24) also had the highest levels of serum IgG antibody. However, this observation did not hold true for other animals (Le. rats exhibiting low numbers of foci, or no foci at all. had higher levels of antibody than rats exhibiting more lung foci).
In conclusion, and based on the results of this study, it is believed that the test item could cause respiratory sensitization if the exposure concentration was higher and/or of a longer duration.

Positive control results:

Not tested

Negative control results:

Not tested

Interpretation of results:

Category 1 (respiratory sensitising) based on GHS criteria

Conclusions:

Based on the results of this study, it is believed that PMDA could cause respiratory sensitization if the exposure concentration was higher and/or of a longer duration.

Executive summary:

The purpose of this study was to determine the pulmonary sensitization potential of of the test item in male and female rats following multiple inhalation exposures. The time-weighted average concentrations of the test item for the five exposures and one challenge were 56.5 and 48.6 ug/m3, respectively. No significant clinical signs were observed in any rat during the study. There were no statistically significant effects of treatment on body weight. lung foci or absolute and relative lung weight and volume. Serum IgG antibody levels_were significantly elevated in the PMDA-exposed male rats only. When antibody values for the males and females were combined, these values were also statistically significant from controls. The three test item exposed males which had the highest number of lung foci (i.e. 14, 20 and 24) also had the highest levels of serum IgG antibody. However, this observation did not hold true for other animals (Le. rats exhibiting low numbers of foci, or no foci at all. had higher levels of antibody than rats exhibiting more lung foci).

In conclusion, and based on the results of this study, it is believed that the test item could cause respiratory sensitization if the exposure concentration was higher and/or of a longer duration.

Reference 2

Endpoint:

respiratory sensitisation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

September 1987 - January 1991

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

no guideline available

GLP compliance:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Lot/batch No.of test material: identification no. 10820-51-R2
- Expiration date of the lot/batch: no data

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature (approximately 20°C)
- Stability under test conditions: stable

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories. Inc., Portage. MI, USA

ENVIRONMENTAL CONDITIONS
- no data

Route of induction exposure:

inhalation

Route of challenge exposure:

inhalation

Vehicle:

unchanged (no vehicle)

Concentration:

Induction and challenge exposure: 500 microgr/m3 of test article aerosol in air

No. of animals per dose:

10 rats/sex/group

Details on study design:

Part 1:
The purpose of this experiment was to determine the respiratory sensitization potential of PMDA in rats.
Two groups of 10 male and 10 female Sprague-Dawley rats (Charles River Laboratories, Portage, Ml each were utilized in this part of the study. One group was exposed to a target concentration of 500 ug/m3 of PMDA, 6 hours/dayfor 5 days. The second group was not exposed. The PMDA-exposed rats were
rested for 2 weeks and then challenged with PMDA at the same target concentration for 6 hours. The treated rats along with the nonchallenged control
rats were fasted for 18 hours, euthanlzed and necropsied. The lungs from five male treated rats and three male control rats were processed and examined microscopically.

Part 2:
The purpose of this experiment was to determine if cross-sensitization between PMDA and Trimellitic Anhydride (TMA) can occur. Two groups of twelve male Sprague-Dawley rats (Charles River Laboratories, Portage, MI) were utilized in this part of the study. Both groups were expose to PMDA at a target concentration of 500 ug/m3, 6 hours/day for 5 days. The rats were rested 2 weeks and one group was challenged with TMA at 500 ug/m3 ·for 6 hours, while the other group was not challenged. All rats were euthanized and necropsied 18 hours following the challenge exposure. The lungs from five challenged and three nonchallenged rats were processed and examined microscopically.

Challenge controls:

None

Positive control substance(s):

none

Negative control substance(s):

none

Results:

The study consisted of two parts. The first part included two groups of 10 male and 10 female Sprague-Dawley rats each; one group was exposed to Pyromellitic Dianhydride (PMDA} as a particulate aerosol at a target concentration of 500 ug/m3, 6 hours/day for 5 days. The other group was a nonexposed control. Following a 2-week rest period, the PMDA-exposed group was challenged with the same concentration of PMDA for 6 hours.
In the second part of the study, two groups of 12 male rats each were exposed to 500 ug!m3 PMDA, 6 hours/day for 5 days. Following a 2-week rest period, one of the groups was challenged with a single inhalation exposure to 500 uglm3 of Trimellitic Anhydride (TMA}. The other group was not challenged.
The analytical time-weighted average concentrations of PMDA for the five part 1 exposures, five part 2 exposures and one challenge were 556, 521 and 639 ug/m3, respectively. The time-weighted average challenge concentration for TMA was 441 ug/m3.
None of the rats died during the study. In the PMDA-exposed / PMDA-challenged rats, significant increases in relative lung weight, number of foci/lung and PMDA specific serum IgG antibody were observed compared to nonchallenged controls. Females showed significantly higher serum IgG antibody levels than did males after PMDAchallenge. Microscopic lung lesions in the control group consisted of interstitial inflammation and parabronchiai lymphoid infiltrates of miminal to mild severity, while the lung lesions seen in the PMDA-exposed/PMDA-challenged rats included the same lesions cited above but in greater severity (i.e. mild to marked} as well as mild to marked alveolar hemorrhage and perivascular acute and chronic inflammation. Thus, significant increases in lung lesions and PMDA-speclfic serum IgG antibody levels indicated that PMDA induces respiratory sensitization in the rat. PMDA-exposed / TMA-challenged males had significantly increased absolute and relative lung weights and numbers of foci/lung compared to the PMDA-exposed / nonchallenged males. Both groups had serum IgG antibody levels comparable to those of the PMDA-exposed / challenged males of part 1, and they were all significantly increased compared to the part 1 male controls. TMA-challenged males had significantly more foci/lung than did PMDA-challenged males. Microscopic lung lesions were similar (i.e. chronic interstitial inflammation, parabronchial lymphoid infiltrates, alveolar hemorrhage and perivascular acute and chronic inflammation), but were of greater severity in the TMA-cballenged rats than in the PMDA-challenged rats. Thus, there exists cross-sensitization reaction between PMDA and TMA, and the response appeared to be stronger when PMDA-exposed rats were challenged with a single exposure to TMA.

Positive control results:

Not tested

Negative control results:

Not tested

Interpretation of results:

Category 1 (respiratory sensitising) based on GHS criteria

Conclusions:

Based on the results of this study, PMDA induces respiratory sensitization in the rat. There exists cross-sensitization reaction between PMDA and TMA, and the response appeared to be stronger when PMDA-exposed rats were challenged with a single exposure to TMA.

Executive summary:

The study consisted of two parts. The first part included two groups of 10 male and 10 female Sprague-Dawley rats each; one group was exposed to Pyromellitic Dianhydride (PMDA} as a particulate aerosol at a target concentration of 500 ug/m3, 6 hours/day for 5 days. The other group was a nonexposed control. Following a 2-week rest period, the PMDA-exposed group was challenged with the same concentration of PMDA for 6 hours.

In the second part of the study, two groups of 12 male rats each were exposed to 500 ug!m3 PMDA, 6 hours/day for 5 days. Following a 2-week rest period, one of the groups was challenged with a single inhalation exposure to 500 uglm3 of Trimellitic Anhydride (TMA}. The other group was not challenged.

The analytical time-weighted average concentrations of PMDA for the five part 1 exposures, five part 2 exposures and one challenge were 556, 521 and 639 ug/m3, respectively. The time-weighted average challenge concentration for TMA was 441 ug/m3.

None of the rats died during the study. In the PMDA-exposed / PMDA-challenged rats, significant increases in relative lung weight, number of foci/lung and PMDA specific serum IgG antibody were observed compared to nonchallenged controls. Females showed significantly higher serum IgG antibody levels than did males after PMDAchallenge. Microscopic lung lesions in the control group consisted of interstitial inflammation and parabronchiai lymphoid infiltrates of miminal to mild severity, while the lung lesions seen in the PMDA-exposed/PMDA-challenged rats included the same lesions cited above but in greater severity (i.e. mild to marked} as well as mild to marked alveolar hemorrhage and perivascular acute and chronic inflammation. Thus, significant increases in lung lesions and PMDA-speclfic serum IgG antibody levels indicated that PMDA induces respiratory sensitization in the rat. PMDA-exposed / TMA-challenged males had significantly increased absolute and relative lung weights and numbers of foci/lung compared to the PMDA-exposed / nonchallenged males. Both groups had serum IgG antibody levels comparable to those of the PMDA-exposed / challenged males of part 1, and they were all significantly increased compared to the part 1 male controls. TMA-challenged males had significantly more foci/lung than did PMDA-challenged males. Microscopic lung lesions were similar (i.e. chronic interstitial inflammation, parabronchial lymphoid infiltrates, alveolar hemorrhage and perivascular acute and chronic inflammation), but were of greater severity in the TMA-cballenged rats than in the PMDA-challenged rats. Thus, there exists cross-sensitization reaction between PMDA and TMA, and the response appeared to be stronger when PMDA-exposed rats were challenged with a single exposure to TMA.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Justification for classification or non-classification

The test material was considered to be a skin sensitiser under the conditions of the LLNA test and is therefore classified Category 1 and as respiratory sensitizer Cat .1 based on GHS criteria.