Dicyclohexyl phthalate

Endpoint summary

Description of key information

Oral, LD50 > 2000 mg/kg bw , rat (OECD 423 )
Dermal, LD50 > 2000 mg/kg bw , rat (OECD 402 )
In accordance with column 2 of REACH Annex VIII, the acute toxicity by inhalation study (required in section 8.5.2) does not need to be conducted as acute toxicity studies are available for the oral and dermal routes of exposure.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 7th June to 24 th June 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study in compliance with international recognized guidelines

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Species:

rat

Strain:

other: Sprague Dawley SD

Sex:

female

Details on test animals or test system and environmental conditions:

Animal supply and acclimatisation

Species and strain: Rat, Sprague Dawley SD
Number and sex: Females (nulliparous and non-pregnant)
Age and weight range (at order): 6 to 7 weeks old, 150 to 174 grams
Supplier: Charles River Italia S.p.A., Calco (Lecco), Italy
Breeder: Charles River Italia S.p.A., Calco (Lecco), Italy
Date of arrival: 31 May 2012
Weight range at arrival: 160 to 171 grams
Acclimatisation period: At least 5 days
Veterinary health check: After arrival

Caging

No. of animals/cage: 3 during the study; up to 5 during acclimatisation
Housing: polisulphone solid bottomed cages measuring 42.5x26.6x18.5 cm (during acclimatisation) and 59x38.5x20 (during the study) cm with nesting material
Cage tray control: Daily inspected and changed as necessary (at least 3 times/week)

Water and diet

Water: Drinking water supplied to each cage via a water bottle
Water supply: Ad libitum
Diet: 4 RF 18 (Mucedola S.r.l., Via G. Galilei, 4, 20019, Settimo Milanese (MI) Italy)
Diet supply: Ad libitum throughout the study except for dosing procedure indicated in section 4.2.2


Housing conditions (parameters set)

Room lighting : Artificial (fluorescent tubes), daily light/dark cycle of 12/12 hours
Air changes : Approximately 15 to 20 air changes per hour
Temperature range: 22°C ± 2°C
Relative humidity range: 55% ± 15%
Actual conditions were monitored and recorded and records retained. No relevant deviations occurred.

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

The acute toxicity of DICYCLOHEXYL PHTHALATE was investigated following a single oral administration (10 mL/kg in corn oil) to the Sprague Dawley rat followed by a 14-day observation period.

Doses:

Frequency of treatment: Once only, on the day of dosing (Day 1).
Fasting procedure: Overnight prior to dosing (Day –1) up to 4 hours after dosing.
Dose calculation: Dose volume of 10 mL/kg of body weight for each animal.
Dosing method: By gavage, using a plastic feeding tube attached to a graded syringe.

No. of animals per sex per dose:

3 females per doses

Control animals:

no

Details on study design:

A first sub-group of 3 female animals was dosed at a level of 2000 mg/kg (Step 1). Mortality did not occur. A second sub-group, similarly composed, was then dosed at the same dose level (Step 2). No mortality occurred.
No further doses were investigated since the objective of the study had been achieved.

Statistics:

not applocable

Preliminary study:

not applicable

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred in the 6 animals dosed in two sub-groups treated at 2000 mg/kg (Steps 1 and 2).

Clinical signs:

other: No clinical signs were recorded in the 6 animals dosed in two sub-groups treated at 2000 mg/kg (Steps 1 and 2).

Gross pathology:

At necropsy examination, no abnormalities were observed in any animal of the study (Steps 1 and 2).

Interpretation of results:

other: not classified

Conclusions:

The acute toxicity of DICYCLOHEXYLPHTHALATE was investigated following a single oral administration (10 mL/kg in corn oil) to the Sprague Dawley rat followed by a 14-day observation period.
No mortality occurred and no signs of toxicity were observed in the 6 animals following dosing at 2000 mg/kg.
These results indicate that the test item DICYCLOHEXYLPHTHALATE did not induce effects of toxicological relevance in the rat following oral administration of a single dose at a level of 2000 mg/kg. The lack of mortality demonstrates the LD50 to be greater than 2000 mg/kg body weight.

Executive summary:

The acute toxicity of DICYCLOHEXYLPHTHALATE was investigated following a single oral administration to the Sprague Dawley rat. The test item (batch 031-12) was administered at 2000 mg/kg (dose volume of 10 mL/kg using corn oil as vehicle).

Animals were observed for a 14 day period, then subjected to necropsy examination.

A first sub-group of 3 female animals was initially dosed at 2000 mg/kg (Step 1). No mortality occurred and no clinical signs were observed.

A second sub-group of 3 female animals was then dosed at the same dose level (Step 2). No deaths occurred and no clinical signs were noted.

Body weight changes recorded during the study were within the expected range for this strain and age of animals.

No abnormalities were observed in any animal treated at necropsy examination performed at the end of the observation period.

These results indicate that the test item DICYCLOHEXYLPHTHALATE did not induce effects in the rat following oral administration of a single dose at a level of 2000 mg/kg. The lack of mortality demonstrates the LD50 to be greater than 2000 mg/kg body weight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 12 June to 27 June 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study in compliance with international recognized guidelines

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Species:

rat

Strain:

other: Sprague Dawley SD

Sex:

male/female

Details on test animals or test system and environmental conditions:

Animal supply and acclimatisation

Species and strain: Rat, Sprague Dawley SD
Sex: Males and females (nulliparous and non-pregnant)
Age and weight range (at order): 6 to 8 weeks old, 176 to 200 grams
Supplier :Charles River Italia S.p.A., Calco (Lecco), Italy
Breeder :Charles River Italia S.p.A., Calco (Lecco), Italy
Date of arrival :31 May 2012
Weight range at arrival: 197 to 203 grams
Acclimatisation period: At least 5 days
Veterinary health check: After arrival


Caging

No. of animals/cage: 5/cage (during acclimatisation ) and individually caged (during study)
Housing: Polycarbonate cages measuring 42.5x26.6x18 cm (during both acclimatisation and study periods) with stainless steel mesh lid and floor. Nesting material was provided inside suitable bedding bags.
Cage tray control: Daily inspected and changed as necessary (at least twice times/week)


Water and diet

Water : Drinking water supplied to each cage via a water bottle
Water supply :Ad libitum
Diet : 4 RF 18 (Mucedola S.r.l., Via G. Galilei, 4, 20019, Settimo Milanese (MI) Italy)
Diet supply : Ad libitum throughout the study


Housing conditions (parameters set)

Room lighting: :Artificial (fluorescent tubes), daily light/dark cycle of 12/12 hours
Air changes: : Approximately 15 to 20 air changes per hour
Temperature range: 22°C ± 2°C
Relative humidity range: 55% ± 15%
Actual conditions were monitored, recorded and records retained. No relevant deviations occurred.

Type of coverage:

occlusive

Vehicle:

corn oil

Details on dermal exposure:

A single group of 5 male and 5 female animals was dosed at a level of 2000 mg/kg.

Duration of exposure:

24 hours

Doses:

Frequency of treatment: Once only, on the day of dosing (Day 1).
Treatment area preparation: on the day before dosing (Day –1).
A single area was clipped free of hair (by an electric clipper equipped with a suitable blade) on the dorsal surfaces of the trunk of each animal (approximately 10% of body surface).
Care was taken to avoid damage to the skin.
Dose calculation: Aliquots were weighed according to the body weight of each animal measured prior to dosing.
Dosing procedure: An aliquot of the supplied test item was spread evenly over an area of approximately 10% of the body surface area. A patch of surgical gauze covered by a strip of synthetic film was placed over the treated site and the whole assembly held in place by encirclin g the trunk of the animal with a length of elastic adhesive bandage, this forming a semi-occlusive barrier.
Exposure time :24 hours
Washing procedure: After exposure, the adhesive bandage and gauze patch were removed. The treatment area was cleaned by gentle swabbing of the skin with cotton wool soaked with lukewarm water.

No. of animals per sex per dose:

5 animals/sex/group

Control animals:

no

Details on study design:

Dose level Animal number
mg/kg Males (even) Females (odd)

2000 2, 4, 6, 8, 10 1, 3, 5, 7, 9

Males and females were identified by even and odd numbers, respectively.

Statistics:

not applicable

Preliminary study:

not applicable

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred in male or female animals after treatment during the observation period.

Clinical signs:

other: Clinical signs were limited to scab on the neck seen in one animal from Day 8 to Day 15 (not confirmed at post mortem examination). This sign is not considered toxicologically relevant.

Gross pathology:

At necropsy examination, no abnormalities were found in any animals, including the examination of the treatment site.

Interpretation of results:

other: not classified

Conclusions:

The acute toxicity of DICYCLOHEXYLPHTHALATE was investigated following dermal administration of a single dose to the rat at 2000 mg/kg.
No mortality occurred following dosing and no toxicologically relevant signs of toxicity were observed.
These results indicate that the test item, DICYCLOHEXYLPHTHALATE, has no toxic effect on the rat following dermal exposure over a 24 hour period at a level of 2000 mg/kg. The lack of mortality demonstrates the LD50 to be greater than 2000 mg/kg

Executive summary:

The acute toxicity of DICYCLOHEXYLPHTHALATE was investigated following dermal administration of a single dose to the rat. A single dose of 2000 mg/kg was administered to a group of 5 male and 5 female animals for 24 hours. After 14 days all animals were killed and subjected to necropsy examination. No mortality occurred and no toxicologically relevant clinical signs were observed in male or female animals during the observation period.

The body weight changes observed during the study were within the expected range for this species and age of animals.

No abnormalities were found at necropsy in the animals at termination of the study. No abnormalities were observed at the treated site.

These results indicate that the test item, DICYCLOHEXYLPHTHALATE, has no toxic effect on the rat following dermal exposure over a 24 hour period at a level of 2000 mg/kg. The lack of mortality demonstrates the LD50 to be greater than 2000 mg/kg.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Additional information

The acute toxicity of dicyclohexylphthalate was evaluated in 1 key oral (gavage) study and a key dermal study.

The oral study was carried out accordin to OECD Guideline No. 423 while the dermal study was carried out according to OECD Guideline 402. Both the studies were compliant with Good Laboratory Practices (GLP).

In the oral test the acute toxicity of DICYCLOHEXYLPHTHALATE was investigated following a single oral administration (10 mL/kg in corn oil) to the Sprague Dawley rat followed by a 14-day observation period.

No mortality occurred and no signs of toxicity were observed in the 6 animals following dosing at 2000 mg/kg.

These results indicate that the test item DICYCLOHEXYLPHTHALATE did not induce effects of toxicological relevance in the rat following oral administration of a single dose at a level of 2000 mg/kg. The lack of mortality demonstrates the LD50 to be greater than 2000 mg/kg body weight.

In the dermal study the acute toxicity of DICYCLOHEXYLPHTHALATE was investigated following dermal administration of a single dose to the rat at 2000 mg/kg.

No mortality occurred following dosing and no toxicologically relevant signs of toxicity were observed.

These results indicate that the test item, DICYCLOHEXYLPHTHALATE, has no toxic effect on the rat following dermal exposure over a 24 hour period at a level of 2000 mg/kg. The lack of mortality demonstrates the LD50 to be greater than 2000 mg/kg.

Justification for selection of acute toxicity – oral endpoint
GLP study in compliance with international recognized guidelines

Justification for selection of acute toxicity – inhalation endpoint
In accordance with column 2 of REACH Annex VIII, the acute toxicity by inhalation study (required in section 8.5.2) does not need to be conducted as acute toxicity studies are available for the oral and dermal routes of exposure.

Justification for selection of acute toxicity – dermal endpoint
GLP study in compliance with international recognized guidelines

Justification for classification or non-classification

The submission substance has a rat acute oral LD50 of greater than 2000 mg/kg bw. As a result, the substance does not meet the criteria for classification according to Regulation (EC) No 1272/2008, Annex I section 3.1.

The submission substance has a rat acute dermal LD50 of greater than 2000 mg/kg bw. As a result, the substance does not meet the criteria for classification according to Regulation (EC) No 1272/2008, Annex I section 3.1.

No data is available to address acute dermal toxicity. As a result, the substance does not meet the criteria for classification according to Regulation (EC) No 1272/2008, Annex I section 3.1