Registration Dossier

Administrative data

Description of key information

Acute toxicity:
Oral: LD50 = > 2000 mg/kg bw
Dermal LD50 = > 2000 mg/kg bw

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 September 9, 2009 to October 2, 2009
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Well described GLP compliant study conducted to recognized international test guidelines
Qualifier:
according to
Guideline:
EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)
Deviations:
no
Qualifier:
according to
Guideline:
OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Test type:
acute toxic class method
Limit test:
no
Species:
rat
Strain:
Sprague-Dawley
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Harlan Italy S.r.l
- Breeder: Harlan Italy S.r.l., 33049 San Pietro al Natisone (UD), Italy
- Age at study initiation: 6/7 week old
- Weight at study initiation: 150-174 grams
- Housing: cage in Polycarbonate measuring 59x38.5x20 cm, with stainless steel mesh lid and floor
- Cage tray control: Daily inspected and changed as necessary (at least 3 times/week)
- Diet :ad libitum , (4 RF 18)
- Water :ad libitum
- Acclimation period:5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C):22°C +/-2
- Humidity (%):55% +/- 15%
- Air changes (per hr):15 to 25
- Photoperiod (hrs dark / hrs light):artificial (Fluorescent tubes) cycle dark/light 12/12

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on oral exposure:
VEHICLE
- Concentration in vehicle:200 mg/ml
- Amount of vehicle (if gavage):10 ml/kg of body weight

Doses:
2000 mg/kg
No. of animals per sex per dose:
2 groups of animals: 3 females per dose per group
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days, Termination Day 15.
- Frequency of observations and weighing:Observations - Daily; Weighing - Allocation (Day-1), Days 1, 2, 8 and 15.
- Terminal observations: Necropsy was carried out on all animals, (gross necropsy examination for both external and internal abnormalities, with particular attention to the gastro-intestinal tract). All abnormalities were recorded.

In life observations
- Mortality and morbidity:Twice daily.
- Clinical signs : Day of dosing (on dosing, approximately 0.5, 2 and 4 hours after dosing).
- Euthanasia method:Carbon dioxide narcosis.

Sex:
female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Mortality:
No mortality was observed .
Clinical signs:
Hunched posture and piloerection were seen in 3 animals on Days 2 and 3. Recovery occurred by Day 4. Brown staining around the left eye was noted in a single animal from Day 12 up to the end of the observation period (Day 15) and red staining on the muzzle was observed in one animal on Day 2 only
Body weight:
Changes in body weight gain observed during the study were within the expected range for this strain and age of animals.
Gross pathology:
No abnormalities observed
Interpretation of results:
GHS criteria not met
Conclusions:
The acute toxicity of Hexahydro-4 Methylphthalic Anhydride was investigated following a single oral administration to rats. No mortality occurred and no significant clinical signs were observed in the 6 animals following dosing at 2000 mg/kg.
These results indicate that the substance has no toxic effect on 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.

European Directives concerning the classification, packaging and labelling of dangerous substances and mixtures (Regulation (EC) Nos. 1907/2006, 1272/2008 and subsequent revisions) would indicate the following:

Classification : Not required
Signal word : None indicated
Hazard statement None indicated
Executive summary:

Acute oral toxicity following a single oral administration has been investigated in the rat in accordance with OECD/EU test methods. No mortality or significant clinical signs occurred indicating that 4-MHHPA has no toxic effect on 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
Dose descriptor:
LD50
Value:
2 000 mg/kg bw

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:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Study period:
from 1993-08-04 to 1993-08-18
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Justification for type of information:
HYPOTHESIS FOR THE ANALOGUE APPROACH AND JUSTIFICATION
The registered substance is regarded as possessing a functional group common to a number of other substances, all consisting of a (bi)cyclic ring structure with a carboxylic acid anhydride group as the single reactive and toxic functional moiety. For the target substance (MHHPA) the bicyclic ring structures are saturated and contain a substituted methyl group. One of the source substances also contains a saturated bicyclic ring structure (HHPA) while another contains an unsaturated bicyclic ring structure (PA). One of the source substances (MTHPA) contains a both substituted methyl group and a partially unsaturated bicyclic ring structure.
It is the reactive anhydride moiety which is deemed mainly responsible for the (eco)toxicological properties of the cyclic anhydrides, this rapidly hydrolyses to form the di-acid particularly on contact with an aqueous medium. The di-acids exert pH effects typical of acids which are well characterized.
Reason / purpose:
reference to other study
Reason / purpose:
read-across source
Qualifier:
according to
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Version / remarks:
1981
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.3 (Acute Toxicity (Dermal))
Version / remarks:
84/449/EEC
Deviations:
no
GLP compliance:
yes (incl. certificate)
Test type:
standard acute method
Limit test:
yes
Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
Five male and five female Sprague-Dawley strain rats were supplied by Charles River (UK) Ltd., Manston, Kent, U.K. At the start of the study the males weighed 234-255 g and the females 207-237 g, and were ten to fourteen weeks of age. After a minimal acclimatisation period of at least five days the animals were selected at random and given a unique number within the study by indelible ink marking on the tail and a number written on a cage card.
The animals were housed in suspended polypropylene cages furnished with softwood sawdust. The animals were housed individually during the 24-hour exposure period and in groups of up to five, by sex, for the remainder of the study. Free access to mains drinking water and food (Rat and Mouse Expanded Diet No. 1, Special Diet Services Limited, Witham, Essex, U.K.) was allowed throughout the study. The animal room was maintained at a temperature of 19-22°C and relative humidity of 50-56 %. The rate of air exchange was approximately 15 changes per hour and the lightening was controlled by a time switch to give 12 hours continuous light and 12 hours darkness.
Type of coverage:
semiocclusive
Vehicle:
unchanged (no vehicle)
Details on dermal exposure:
On the day before treatment the back and flanks of each animal were clipped free of hair using veterinary clippers to expose a skin area of approximately 5 cm x 4 cm. The calculated volume (1.68 mL/kg) of the undiluted test material, as received, was applied uniformly to an area of shorn skin (approximately to 10 % of the total body surface area) using a graduated syringe. A piece of surgical gauze measuring 7 cm x 4 cm was placed over the treatment area and semioccluded with a piece of self-adhesive bandage (HYPERTIE). The bandage was further secured with a piece of BLENDERM wrapped around each end. The animals were caged individually for the 24-hour exposure period. Shortly after dosing the dressings were examined to ensure that they were securely in place. After the 24-hour contact period the bandage was carefully removed and the treated skin and surrounding hair wiped with cotton wool moistened with distilled water to remove any residual test material. The animals were returned to group housing for the remainder of the study period.
Duration of exposure:
24 h
Doses:
2000 mg/kg bw (1.68 mL/kg bw)
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
The animals were observed for deaths or overt signs of toxicity 0.5, 1, 2 and 4 hours after dosing and subsequently once daily for 14 days. The animals were also observed for any dermal reactions after removal of the dressings and subsequently once daily for the remainder of the study. Individual bodyweights were recorded prior to application of the test material on Day 0 and on Days 7 and 14.
At the end of the study the animals were killed by cervical dislocation and subjected to gross pathological examination. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded. No tissues were retained.
Statistics:
Data evaluations included the relationship, if any, between the animals' exposure to the test material and the incidence and severity of all abnormalities including behavioural and clinical observations, gross lesions, bodyweight changes, mortality and any other toxicological effects.
Using the mortality data obtained, an estimate of the acute dermal median lethal dose (LD50) of the test material was made.
Preliminary study:
no preliminary study
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Sex:
male/female
Dose descriptor:
LD0
Effect level:
2 000 mg/kg bw
Mortality:
There were no deaths.
Clinical signs:
No signs of systemic toxicity were noted during the study.

Dermal Reactions:
Very slight to well-defined erythema was noted at the treatment sites of all animals one day after dosing with very slight erythema in all females two days after dosing. Haemorrhage of the dermal capillaries was noted in all animals one day after dosing and persisted in all females two days after dosing. Crust formation was noted at the treatment sites of two females three and four days after dosing. Treatment sites appeared normal two to five days after dosing.
Body weight:
All animals showed expected gain in bodyweight during the study.
Gross pathology:
No abnormalities were noted at necropsy.
Other findings:
none
Interpretation of results:
GHS criteria not met
Conclusions:
The acute dermal median lethal dose (LD50) of the tested (source) material, tetrahydromethylphthalic anhydride, in the Sprague-Dawley strain rat was found to be greater than 2000 mg/kg bw.
Executive summary:

A study was performed on the (source) substance, tetrahydromethylphthalic anhydride, to assess the acute dermal toxicity of the test material in the Sprague-Dawley strain rat. The method used followed that described in the OECD Guidelines for Testing of Chemicals (1981) No. 402 "Acute Dermal Toxicity" referenced as Method B.3 in Commission Directive 84/449/EEC (which constitutes Annex V of Council Directive 67/548/EEC).

A group of ten animals (five males and five females) was given a single 24-hour, semi-occluded dermal application to intact skin at a dose level of 2000 mg/kg bw. The animals were observed for fourteen days after the day of treatment and were then killed for gross pathological examination. There were no deaths. No signs of systemic toxicity were noted during the study. Very slight to well-defined erythema was noted at the treatment sites of all animals. Other skin reactions noted were haemorrhage of the dermal capillaries and crust formation. Treatment sites appeared normal two to five days after dosing. All animals showed expected gain in bodyweight during the study. No abnormalities were noted at necropsy.

The acute dermal median lethal dose (LD50) of the tested material in the Sprague-Dawley strain rat was found to be greater than 2000 mg/kg bodyweight and a similar outrcome is expected for the target substance, 4 -methylhexahydrophthalic anhydride.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
Value:
2 000 mg/kg bw

Additional information

Acute oral toxicity following a single oral administration has been investigated in the rat in accordance with OECD/EU test methods. No mortality or significant clinical signs occurred indicating that 4-MHHPA has no toxic effect on 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.

Acute dermal toxicity of HHPA and MTHPA, both analogues of 4 -MHHPA, has been investigated in the rabbit and rat. These substances were not toxic by the dermal route.

Justification for classification or non-classification

Non classification is justified by the lack of observed toxicity in acute studies by the oral and dermal routes of administration.