Registration Dossier

A Klimisch-2-rated study on acute oral toxicity with target chemical toluene-2,5-diamine revealed a LD50 of 102 mg/kg bw.

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1975-08-01 to 1975-10-07

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Huntingdon study, conducted in 1975, non GLP, report without many details, therefore considered as reliable with restrictions.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

not specified

Remarks:

study conducted in 1975

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

other: CFY

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS- Source: no data- Age at study initiation: no data- Weight at study initiation: 98 - 120 g- Fasting period before study: starved overnight before treatment- Housing: grouping of 5 animals per sex per dose- Diet (e.g. ad libitum): no data- Water (e.g. ad libitum): no data- Acclimation period: no dataENVIRONMENTAL CONDITIONS- Temperature (°C): no data- Humidity (%): no data- Air changes (per hr): no data - Photoperiod (hrs dark / hrs light): no dataIN-LIFE DATES: no data

Route of administration:

oral: gavage

Vehicle:

other: aquous solution of sodium sulphite (0.05%)

Details on oral exposure:

VEHICLE- Concentration in vehicle: 10% solution- Amount of vehicle (if gavage): 2.5 mL- Justification for choice of vehicle: no justification given- Lot/batch no. (if required): no data- Purity: no dataMAXIMUM DOSE VOLUME APPLIED: 2.5 mL

Doses:

0, 64, 100, 160, and 250 mg/kg

No. of animals per sex per dose:

5

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days - Frequency of observations and weighing: According to the original study report, "during the observation period of 14 days, a record was kept on all mortalities and signs of toxicity".- Necropsy of survivors performed: yes- Other examinations performed: clinical signs, body weight (gain)

Statistics:

95% confidence limits were calculated by the method of Weil C.S. (1952)

Preliminary study:

The results of preliminary range finding tests indicated that the median lethal oral dose (LD50) was in the region of 64 to 250 mg/kg bw.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

102 mg/kg bw

Based on:

test mat.

95% CL:

69 - 152

Mortality:

Males:0 mg/kg bw: 0 deaths / 5 test animals64 mg/kg bw: 3/5100 mg/kg bw: 4/5160 mg/kg bw: 0/5250 mg/kg bw: 5/5Females:0 mg/kg bw: 0 deaths / 5 test animals64 mg/kg bw: 0/5100 mg/kg bw: 3/5160 mg/kg bw: 5/5250 mg/kg bw: 4/5Deaths occured from 1 hour to 22 hours of treatment.

Clinical signs:

other: Lethargy, pilo erection, apraxia and increased salivation. Increase respiratory rate in rats treated at 100 mg/kg bw, and decreased respiratory rate in rats treated above 100 mg/kg bw.

Gross pathology:

Autopsy of dead animals revealed slight haemorrhage of lungs, pallor of the spleen, darkening of the liver, and injection of peritoneal blood vessels. for survivors after recovery, the terminal autopsy findings were normal.

Other findings:

none reported

Interpretation of results:

toxic

Remarks:

Migrated informationCriteria used for interpretation of results: OECD GHS

Conclusions:

With a LD50 = 102 mg/kg bw, test item toluene-2,5-diamine shall be classified as oral acute toxic category 3, (toxic if swallowed, H301) according to the GHS/CLP classification system.

Executive summary:

The purpose of this study was to evaluate the acute oral toxicity of test item toluene-2,5 -diamine. The study was conducted in 1975 under non GLP conditions, without many details on the methodology given in the study report. Still the procedure as described in the study report obviously was similar to the protocol as given by OECD Guideline 401, thus the study is considered as reliable.

With a LD50 = 102 mg/kg bw, test item toluene-2,5-diamine shall be classified as oral acute toxic category 3, (toxic if swallowed, H301) according to the GHS/CLP classification system. Within the former DSD classification system the classification as T; R25 (toxic if swallowed) applies. Both classifications are in line with the harmonised classification already given for the test item (Annex VI of CLP regulation, Index # 612 -125 -00 -3).

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

102 mg/kg bw

Quality of whole database:

reliability 2

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

calculation (if not (Q)SAR)

Remarks:

Migrated phrase: estimated by calculation

Adequacy of study:

key study

Study period:

2012

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable calculated/extrapolated data

Qualifier:

no guideline available

Principles of method if other than guideline:

To assess the acute inhalational toxicity of toluene-2,5-diamine, a kinetic based calculation was done. The kinetic data were derived from various kinetic studies, and the details of the test methods and the results are provided in this summary (refer to executive summary for details). The derived data were consistent with the determined acute toxicity values (derived by in-vivo studies) from p-phenylenediamine, the most appropriate analogue for toluene-2,5-diamine.

Test type:

other: Estimated data by calculation

Limit test:

no

Sex:

not specified

Dose descriptor:

LC50

Effect level:

0.99 mg/L air

Based on:

other: kinetic based calculation

Exp. duration:

4 h

Remarks on result:

other: The calculated inhalational LC50 of 0.99 mg/L for toluene-2,5-diamine is comparable to the determined value for p-phenylenediamine (0.92 mg/L)

Interpretation of results:

Toxicity Category IV

Remarks:

Migrated informationCriteria used for interpretation of results: EU

Conclusions:

Based on the available acute oral toxicity and kinetic data for toluene-2,5-diamine, the extrapolated acute inhalation toxicity (4 h, LC50) of toluene-2,5-diamine was 0.99 mg/L. This value is comparable to the determined value for p-phenylenediamine (0.92 mg/L).

Executive summary:

To assess the acute dermal and inhalational toxicity of toluene-2,5-diamine, a kinetic based calculation was done. The kinetic data were derived from various kinetic studies, and the details of the test methods and the results are provided in the SCCS Opinion1479/12, 26 – 27June 2012.In addition, the calculated data for toluene-2,5-diamine were compared with those of the most appropriate analogue, the p-phenylenediamine (refer to below table).

COLIPA Number

Chemical Name

CAS Number

Acute Toxicity

Oral

LD₅₀

Dermal

LD₅₀

Inhalation LC₅₀

Colipa No. A005

Toluene-2,5-Diamine

95-70-5 (free base)

102 mg/kg bw

(rat)

> 2000 mg/ kg bw

(rat, extrapolated)

0.99 mg/l,

(4h, rat, extrapolated)

Colipa No. A007

p-Phenylenediamine

106-50-3 (free base)

80-100 mg/kg bw

(rat)

> 7940 mg/kg bw

(male/female rabbit)

0.92 mg/l air

(4 h ,rat)

Studies used for the determination of acute toxicity of TOLUENE-2,5-DIAMINE:

Acute Oral Toxicity study result

LD₅₀oral: 102 mg/kg bw in the rat (CFY strain); “The acute median lethal oral dose was calculated to be 102 mg/kg bw (95% confidence limits of 69-152 mg/kg bw)”

Toxicokinetic study results in Sprague Dawley rats:

Dose levels:

IV: 2.5 mg/kg bw

Oral: 2.5, 25 mg/kg bw

Dermal:0.5 mg/cm² equal to 33.3 mg/kg bw

Bioavailability, assuming 100% bioavailability IV

Oral dosing: 69 %

Dermal dosing: 2 %

The studies are summarized as follows in SCCS 1479/12:

“In toxicokinetic studies with Sprague-Dawley rats the comparison of AUCs showed differences between oral (25 mg/kg bw: 112 mg_eqx h/l) and dermal application (33 mg/kg bw in formulation: 2.27 mg_eqx h/l). Following 2.5 mg/kg bw the AUC was 8.53 mg_eqx h/l. The bioavailability (derived from comparison to iv administration) after oral dosing of 10 mg/kg bw was 69% while 2% bioavailability was found after dermal administration in a formulation.”

This summary provides calculation ofextrapolation of the acute inhalation toxicity of toluene-2,5-diamine. The summary of calculation of extrapolation of the acute dermal toxicity is provided under section 7.2.3 of IUCLID.

Extrapolation of the acute inhalational toxicity of TOLUENE-2,5-DIAMINE:

Required maximum exposure concentration to test material (OECD 403): 5 mg/L

Assumed body weight of the rat for the calculation: 250 g

Respiratory volume of the rat: 0.074 L/min

Required duration (OECD 403): 4 h

0.074 L/min x 60 min x 4 hour = 17.76L

Toluene-2,5-diamine LD₅₀oral= 102 mg/kg bw in the rat

Calculation:

Maximum achievable exposure regarding required 5 mg/L for 4 hours (OECD 403:

17.76 L x 5 mg/L = 88.8 mg/rat

88.8 mg/0.250 kg bw = 355 mg/kg bw maximum achievable exposure

Oral Bioavailability = 69% (at 25 mg/kg bw, using the data from the toxicokinetic study in Sprague Dawley rats)

Inhalation Bioavailability: Assumed to be 100%

Determination of the correction factor oral vs. inhalation route:

69% oral vs. 100% inhalation = 0.69

LC_{50 calc}inhal.: 102 mg/kg bw x 0.250 kg bw x 0.69/17.76 L = 0.99 mg/L

LC₅₀inhal. forp-phenylenediamine = 0.92 mg/L

LC_{50 calc}inhal. for toluene-2,5-diamine = 0.99 mg/L

The calculated inhalational LC₅₀of 0.99 mg/L for toluene-2,5-diamine is comparable to the determined value forp-phenylenediamine (0.92 mg/L)

The calculated inhalation toxicity value for toluene-2,5-diamine is in the same order of magnitude (0.99 mg/l calculated versus 1.0-5.0 mg/l) as the official classification of Acute Tox Cat 4; H332 in Annex VI of the CLP regulation which is being applied in case of 1 mg/L<LC₅₀<5 mg/L (for dusts/mists).

ASSESSMENT OF VALIDITY:

Since theWeight of Evidence Approach (WoE)used was considered as sufficiently robust to determine the acute inhalation toxic potential of toluene-2,5-diamine, the performance of an animal test for hazard identification purposes was considered to be not justified

In addition the completion of acute toxicity studies ontoluene-2,5-diamine as an ingredient used in cosmetic products would not be considered to comply with the EU regulations regarding animal testing. Furthermore, applying WoE complies with the REACH regulation to avoid animal testing. The validity of the WoE/extrapolation approach used in order to estimate the acute toxicity potential of toluene-2,5-diamine by inhalation route was finally confirmed by the comparison of the extrapolated values on toluene-2,5-diamine with experimental values obtained on the primary member of thep-phenylenediamine family,p-phenylenediamine.

In conclusion, the extrapolated acute inhalation toxicity (4 h, LC50) of toluene-2,5-diamine was 0.99 mg/L. This value is comparable to the determined value for p-phenylenediamine (0.92 mg/L)

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LC50

Value:

990 mg/m³ air

Reference

Endpoint:

acute toxicity: dermal

Type of information:

calculation (if not (Q)SAR)

Remarks:

Migrated phrase: estimated by calculation

Adequacy of study:

key study

Study period:

2012

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable calculated/extrapolated data

Qualifier:

no guideline available

Principles of method if other than guideline:

To assess the acute dermal toxicity of toluene-2,5-diamine, a kinetic based calculation was done. The kinetic data were derived from various kinetic studies, and the details of the test methods and the results are provided in this summary (refer to executive summary for details). The derived data were consistent with the determined acute toxicity values (derived by in-vivo studies) from p-phenylenediamine, the most appropriate analogue for toluene-2,5-diamine.

Test type:

other: Estimated data by calculation

Limit test:

no

Sex:

not specified

Dose descriptor:

LD50

Effect level:

3 520 mg/kg bw

Based on:

other: kinetic based calculation

Remarks on result:

other: The calculated dermal LD50 for toluene-2,5-diamine can be assumed to be > 2000 mg/kg bw, which is consistent with the LD50 dermal for the analogue, p-phenylenediamine

Interpretation of results:

not classified

Remarks:

Migrated informationCriteria used for interpretation of results: EU

Conclusions:

Based on the available acute oral toxicity and kinetic data for toluene-2,5-diamine, the extrapolated acute dermal toxicity of toluene-2,5-diamine was 3520 mg/kg bw, while the determined LD50 dermal for p-phenylenediamine is > 7940 mg/kg bw. In conclusion, the LD50 dermal for toluene-2,5-diamine can be assumed to be > 2000 mg/kg bw, which is consistent with the LD50 dermal for the analogue, namely p-phenylenediamine

Executive summary:

To assess the acute dermal and inhalational toxicity of toluene-2,5-diamine, a kinetic based calculation was done. The kinetic data were derived from various kinetic studies, and the details of the test methods and the results are provided in the SCCS Opinion1479/12, 26 – 27June 2012.In addition, the calculated data for toluene-2,5-diamine were compared with those of the most appropriate analogue, the p-phenylenediamine (refer to below table).

COLIPA Number

Chemical Name

CAS Number

Acute Toxicity

Oral

LD₅₀

Dermal

LD₅₀

Inhalation LC₅₀

Colipa No. A005

Toluene-2,5-Diamine

95-70-5 (free base)

102 mg/kg bw

(rat)

> 2000 mg/ kg bw

(rat, extrapolated)

0.99 mg/l,

(4h, rat, extrapolated)

Colipa No. A007

p-phenylenediamine

106-50-3 (free base)

80-100 mg/kg bw

(rat)

> 7940 mg/kg bw

(male/female rabbit)

0.92 mg/L air

(4 h ,rat)

Studies used for the determination of acute toxicity of TOLUENE-2,5-DIAMINE:

Acute Oral Toxicity study result

LD₅₀oral: 102 mg/kg bw in the rat (CFY strain); “The acute median lethal oral dose was calculated to be 102 mg/kg bw (95% confidence limits of 69-152 mg/kg bw)”

Toxicokinetic study results in Sprague Dawley rats:

Dose levels:

IV: 2.5 mg/kg bw

Oral: 2.5, 25 mg/kg bw

Dermal:0.5 mg/cm² equal to 33.3 mg/kg bw

Bioavailability, assuming 100% bioavailability IV

Oral dosing: 69 %

Dermal dosing: 2 %

The studies are summarized as follows in SCCS 1479/12:

“In toxicokinetic studies with Sprague-Dawley rats the comparison of AUCs showed differences between oral (25 mg/kg bw: 112 mg_eqx h/l) and dermal application (33 mg/kg bw in formulation: 2.27 mg_eqx h/l). Following 2.5 mg/kg bw the AUC was 8.53 mg_eqx h/l. The bioavailability (derived from comparison to iv administration) after oral dosing of 10 mg/kg bw was 69% while 2% bioavailability was found after dermal administration in a formulation.”

This summary provides calculation ofextrapolation of the acute dermal toxicity of toluene-2,5-diamine. The summary of calculation of extrapolation of the acute inhalation toxicity is provided under section 7.2.2 of IUCLID.

Extrapolation of the acute dermal toxicity of TOLUENE-2,5-DIAMINE:

TOLUENE-2,5-DIAMINE LD₅₀oral = 102 mg/kg bw in the rat

Oral bioavailability = 69% (at 25.0 mg/kg bw, using the data from the toxicokinetic study in Sprague Dawley rats)

Dermal bioavailability =2% (at 33.3 mg/kg bw)

Calculation:

Determination of the correction factor oral vs. dermal route

69 % oral vs. 2 % dermal = 34.5 (69 : 2 = 34.5)

LD_{50 calc}dermal: 102 mg/kg bw x 34.5 = 3520 mg/kg bw

Thus, the calculated LD₅₀dermal for toluene-2,5-diamine is 3520 mg/kg bw, while the determined LD₅₀dermal for p-phenylenediamine is > 7940 mg/kg bw.

The calculated dermal toxicity is >2000 mg/kg and does not support the official classification of toluene-2,5-diamine as Acute Tox Cat 4; H312. The calculated classification as not harmful in contact with skin is the same as that determined for the analoguep-phenylenediamine based on a rat study. This is also in contrast to the official classification ofp-phenylenediamine as Acute Tox 3;H311 in Annex VI of the CLP regulation. However, the official classification fortoluene-2,5-diamine as laid down in Annex VI of the CLP regulation is not based on animal data, as stated by the ECHA

ASSESSMENT OF VALIDITY:

Since theWeight of Evidence Approach (WoE)used was considered as sufficiently robust to determine the acute dermal toxic potential of toluene-2,5-diamine, the performance of an animal test for hazard identification purposes was considered to be not justified.

Based on the REACH regulation “REACH VO - Annex VIII, 8.5.3., (3).), testing of the dermal route is only required, if there is a potential for a significant rate of absorption through the skin. The ADME data demonstrated, that the oral bioavailability of toluene-2,5-diaminein rats is 34.5 times higher than the dermal bioavailability

In addition, the completion of acute toxicity studies ontoluene-2,5-diamineas an ingredient used in cosmetic products would not be considered to comply with the EU regulations regarding animal testing. Furthermore, applying WoE complies with the REACH regulation to avoid animal testing. The validity of the WoE/extrapolation approach used in order to estimate the acute toxicity potential of toluene-2,5-diamineby dermal routes was finally confirmed by the comparison of the extrapolated values on toluene-2,5-diaminewith experimental values obtained on the primary member of thep-phenylenediamine family,p-phenylenediamine.

In conclusion, the LD₅₀dermal for toluene-2,5-diaminecan be assumed to be > 2000 mg/kg bw, which is consistent with the LD₅₀dermal for the analogue, namely p-phenylenediamine.

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

3 519 mg/kg bw

Quality of whole database:

reliability 2

Acute oral toxicity or LD50 value was determined by oral administration of test substance to five dose groups of rats. Subsequently, observations of effects such as clinical signs, cage side observation and mortality are made for 14 days. The test method employed in this study is comparable to OECD Guideline 401 (Acute Oral Toxicity). The LD 50 = 102 mg/kg bw that mean that the substance is harmful by ingestion or H301 toxic by ingestion according to CLP

Based on the available acute oral toxicity and kinetic data for toluene-2,5-diamine, the extrapolated acute dermal toxicity of toluene-2,5-diamine can be assumed to be around 3519 mg/kg bw for the free base. Not classified according to CLP but official classification is maintained H312, harmful effect.

Based on the available acute oral toxicity and kinetic data for toluene-2,5-diamine, the extrapolated acute inhalation toxicity (4 h, LC50) of toluene-2,5-diamine was 0.99 mg/L. This value is comparable to the determined value for p-phenylenediamine (0.92 mg/L). It indicate an toxic effect by inhalation H331, the official classifictaion indicated harmful effect H332.

Justification for selection of acute toxicity – oral endpoint
Acute oral toxicity or LD50 value was determined by oral administration of test substance toluene-2,5-diamine to five dose groups of rats. Subsequently, observations of effects such as clinical signs, cage side observation and mortality are made for 14 days. The test method employed in this study is comparable to OECD Guideline 401 (Acute Oral Toxicity)

Justification for selection of acute toxicity – inhalation endpoint
Based on the available acute oral toxicity and kinetic data for toluene-2,5-diamine, the extrapolated acute inhalation toxicity (4 h, LC50) of toluene-2,5-diamine was 0.99 mg/L. This value is comparable to the determined value for p-phenylenediamine (0.92 mg/L).

Justification for selection of acute toxicity – dermal endpoint
Based on the available acute oral toxicity and kinetic data for toluene-2,5-diamine, the extrapolated acute dermal toxicity of toluene-2,5-diamine can be assumed to be around 3519 mg/kg bw for the free base.

Acute oral toxicity or LD50 value was determined by oral administration of test substance to five dose groups of rats. Subsequently, observations of effects such as clinical signs, cage side observation and mortality are made for 14 days. The test method employed in this study is comparable to OECD Guideline 401 (Acute Oral Toxicity). The LD 50 = 102 mg/kg bw that mean that the subsnace is toxic cat 3 by ingestion according to CLP.

Based on the available acute oral toxicity and kinetic data for toluene-2,5-diamine, the extrapolated acute dermal toxicity of toluene-2,5-diamine can be assumed to be around 3519 mg/kg bw for the free base. But warning , cat 4 should be maintained according to official classification.

Based on the available acute oral toxicity and kinetic data for toluene-2,5-diamine, the extrapolated acute inhalation toxicity (4 h, LC50) of toluene-2,5-diamine was 0.99 mg/L. This value is comparable to the determined value for p-phenylenediamine (0.92 mg/L). It indicate a toxic effect by inhalation, toxic cat 3 according to CLP