Benzenemethanaminium, N,N,N-trimethyl-, 2-hydroxy-2-methylpropanoate (1:1)

Endpoint summary

Description of key information

The acute oral LD50 in rat was higher than  50 mg/kg bw  (no mortality) and lower than  300 mg/kg bw (100% mortality) as investigated in a GLP and OECD 423 compliant study. Mortality occurred shortly after doing. No specific target organ for acute toxicity could be identified.

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:

03 May 2012 to 31 June 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2001

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Version / remarks:

1998

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Wiga GmbH, Sandhofer Weg 7, 97633 Sulzfeld, Germany
- Age at study initiation: Young adult animals (female animals approx. 10 – 11 weeks)
- Fasting period before study: Feed was withdrawn from the animals at least 16 hours before administration, but water was available ad libitum.
- Weight at study initiation: Animals of comparable weight

HOUSING and DIET
- Room temperature/relative humidity: The animals were housed in fully air-conditioned rooms. Central air-conditioning guaranteed a range of 22°C ± 3°C for temperature and of 30 – 70% for relative humidity. There were no deviations from these ranges, which influenced the results of the study.
- Air changes per hour: approx. 10
- Day / night rhythm: 12 h / 12 h (6.00 a.m. – 6.00 p.m. / 6.00 p.m. – 6.00 a.m.)
- Type of cage: Makrolon cage, type III
- Number of animals per cage: Single housing
- Feeding: VRF1(P); SDS Special Diets Services, 67122 Altrip, Germany)
- Drinking water: Tap water ad libitum
- Bedding: H 15005-29; Ssniff, Spezialitäten GmbH (Experimental Animal Diets Inc., 59494 Soest, Germany)
- Enrichment: NGM E-022; ABEDD® LAB & VET Service GmbH, Hasnerstraße 84/6; 1160 Wien – Austria

Route of administration:

oral: gavage

Vehicle:

olive oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 2000 mg/kg bw: 40 g/100 mL; 300 mg/kg bw: 6 g/100 mL; 50 mg/kg bw: 1 g/100 mL
- Amount of vehicle (if gavage): 5.00 mL/kg bw
- Justification for choice of vehicle: Good homogeneity in olive oil Ph.Eur.

DOSAGE PREPARATION: For better handling the test item was ground with a pestle and mortar. The test item preparation was produced for
each application group shortly before application by stirring with a high speed homogenizer (Ultra-Turrax) and a magnetic stirrer. Additionally the homogeneity of the test item preparation during application was ensured by stirring with a magnetic stirrer.

CLASS METHOD
- Rationale for the selection of the starting dose: By request of the sponsor a starting dose of 2000 mg/kg bw was chosen in the first step with 3 female animals. As all animals died, 300 mg/kg bw were administered to 3 female rats in the second step. After administration all animals died in the second step. Therefore 50 mg/kg were given to a further group of three fasted females in the third step. Because no mortality occurred, 50 mg/kg bw were administered to another group of 3 female animals in the fourth step.

Doses:

2000, 300, 50 mg/kg bw

No. of animals per sex per dose:

2000 mg/kg bw: 3 females
300 mg/kg bw: 3 females
50 mg/kg bw: 6 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Individual body weights shortly before administration (day 0), weekly thereafter and on the last day of observation.
- Necropsy of survivors performed: yes
- Pathology: Necropsy with gross-pathology examination on the last day of the observation period after sacrifice by CO2-inhalation in a chamber with increasing concentrations over time. Necropsy of all animals that died before as early as possible after death.
- Clinical signs: Recording of clinical signs several times on the day of administration, and at least once daily thereafter each workday for the individual animals.
- Mortality: A check for any dead or moribund animals was made at least once each workday, these records are archived by Bioassay.
- Histology: No histological examinations were performed.

Sex:

female

Dose descriptor:

LD50

Effect level:

> 50 - < 300 mg/kg bw

Based on:

test mat.

Remarks on result:

other: No mortality occurred at 50 mg/kg bw. No animal survived dosing with 300 mg/kg bw.

Mortality:

All animals died in the 2000 mg/kg bw and 300 mg/kg bw test groups within 1 hour after application.
No mortality occurred in the 50 mg/kg bw test groups

Clinical signs:

other: All animals of the 2000 mg/kg bw test group and 2 animals of the 300 mg/kg bw died immediately after administration. Therefore no clinical signs could be determined. One animal of the 300 mg/kg bw test group showed poor general state, dyspnoea, piloerecti

Gross pathology:

The three animals that died in the 2000 mg/kg bw test group showed liquid content in the stomach and black discoloration of liver. In two animals of the 300 mg/kg bw test group dark red spotted discoloration of the lung was noted at necropsy. One animal of this test group didn’t show any findings. In the 50 mg/kg bw test group no macroscopic pathological findings were noted in the animals sacrificed at the end of the observation period.

Interpretation of results:

toxic

Remarks:

Migrated information Criteria used for interpretation of results: EU

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

discriminating dose

Value:

50 mg/kg bw

Quality of whole database:

Valid without restriction

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Oral:

In an acute oral toxicity study performed according to the Acute Toxic Class method, doses of 2000, 300 and 50 mg/kg bw of the test item (preparations in olive oil Ph.Eur.) were administered to four test groups of three fasted Wistar rats each (2000 mg/kg bw in 3 females, 300 mg/kg bw in 3 females and 50 mg/kg bw in 6 females) by gavage in a sequential manner.

The following test substance-related clinical observations were recorded:

2000 mg/kg (single test group):

· Mortality in all animals

· No clinical findings could be determined because the animals died immediately after administration.

· Macroscopic pathological findings in the animals that died: 1) Liquid content in the stomach, 2) Black discoloration of the liver

300 mg/kg (single test group):

· Mortality in all animals

· Poor general state in one out of three animals

· Dyspnoea in one out of three animals

· Piloerection in one out of three animals

· Abdominal position in one out of three animals

· Chromodacryorrhea in one out of three animals

· No clinical findings in two animals because the animals died immediately after application

· Macroscopic pathological findings in two animals that died: Dark red spotted discoloration of lung

· No macroscopic pathological findings in one animal

50 mg/kg (two test groups):

· No mortality occurred.

· No clinical signs were observed.

The mean body weight of the surviving animals increased within the normal range throughout the study period.

There were no macroscopic pathological findings in the surviving animals sacrificed at the end of the observation period. The acute oral LD50 was calculated to be >50 < 300 mg/kg bw.

Justification for selection of acute toxicity – oral endpoint
GLP and guideline study

Justification for classification or non-classification

Based on available data, the test substance is classified as R25 “Toxic if swallowed” (Directive 67/548/EEC) and Cat. 3/ H301 “Toxic if swallowed” (Regulation (EC) No 1272/2008/EC including 2nd amendment).