Ethyldiisopropylamine

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

yes

Remarks:

Due to failure of the TSE temperature-humidity sensor in the exposure system, the humidity was not measured during the animal exposures.

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Ethyldiisopropylamine

EC Number:

230-392-0

EC Name:

Ethyldiisopropylamine

Cas Number:

7087-68-5

Molecular formula:

C8H19N

IUPAC Name:

ethylbis(propan-2-yl)amine

Test material form:

other: Colorless liquid

Details on test material:

- Name: Ethyldiisopropylamine
- Batch number: A215TC010101
- Chemical name: N-ethyl-N-propan-2-ylpropan-2-amine
- Molecular formula: C8H19N
- CAS number: 7087-68-5
- EC number: 230-392-0
- Purity: 99.79%
- Manufacture date: 11 July 2012
- Date of expiry: 11 July 2014
- Storage conditions: Room temperature, protected from light and humidity, under inert gas (nitrogen)

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Research Models and Services, Germany GmbH, Sandhofer Weg 7, D-97633 Sulzfeld
- Age at study initiation: 8-9 weeks old
- Weight at study initiation: 215 to 375 g (¿: 328-375g; ¿: 215-242g)
- Fasting period before study:
- Housing: Group of 5 (by sex) in type III solid floor cages with stainless steel mesh lids
- Diet: ssniff SM R/M-Z “Autoclavable Complete Feed for Rats and Mice – Breeding and Maintenance” (ssniff Spezialdiäten GmbH, D-59494 Soest Germany; Batch: 445 8440, Expiry: May 2013), ad libitum
- Water: tap water, ad libitum
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 30 – 70
- Air changes (per hr): 15-20
- Photoperiod (hrs dark / hrs light): 12/12h

IN-LIFE DATES: From: To: 12 March 2013-03 April 2013

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

nose only

Vehicle:

clean air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: TSE Rodent Exposure System (TSE Systems GmbH, Bad Homburg, Germany). This system comprises of two, concentric anodised aluminium chambers and a computer control system incorporating pressure detectors and mass flow controllers.
- Method of holding animals in test chamber: The animals were held in polycarbonate restraint tubes located around the chamber which allowed only the animal’s nares to enter the exposure port.
- Source and rate of air: The flow of air through each port was at least 0.7 L/min. This flow rate was considered adequate to minimise re-breathing of the test atmosphere as it is about twice the respiratory minute volume of a rat.
- System of generating particulates/aerosols: The test item was aerosolised using a stainless steel concentric jet nebuliser (TSE Systems GmbH, Bad Homburg, Germany) located at the top of the exposure chamber. The rate of formulation use was controlled by a syringe pump. Compressed air was supplied by means of an oil-free compressor passed through a suitable filter system prior to introduction to the nebuliser.
- Method of particle size determination: The particle size of the test atmosphere was not determined due to the test item was evaporated and were non-condensing.
- Treatment of exhaust air:
- Temperature, humidity, O2 and CO2 in air chamber: monitored continuously and recorded every minute during each exposure period by the TSE-DACO monitoring system

TEST ATMOSPHERE
- Brief description of analytical method used: The test atmosphere was sampled at regular intervals during the exposure period. Samples were taken from an unoccupied exposure port (representing the animal’s breathing zone) by pulling a suitable, known volume (56 ml injected sample or 60 L direct sample) of test atmosphere by a 60 ml syringe and then the samples were analyzed using a calibrated Miran 1A CVF gas analyser containing a 5.64 L measuring loop and recorded by a TESTO 175-S2 Data Logger.
- Samples taken from breathing zone: yes

TEST ATMOSPHERE (if not tabulated)
- Particle size distribution: not relevant for vapours
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.): not relevant for vapours

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

0.48±00.7, 2.07±0.18, 4.34±0.52 and 9.16±0.72 mg/l (analytical conc.)

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

Morbidity/Mortality:
Animals were checked hourly during exposure, one hour after exposure and twice daily (early and late in the working day) during the 14-day observation period for morbidity and/or mortality.

Clinical Signs:
All animals were observed for clinical signs at hourly intervals during exposure, as soon as practically possible following removal from restraint at the end of exposure, one hour after exposure and subsequently once daily for fourteen days.

Bodyweight:
Individual bodyweights were recorded prior to treatment on the day of exposure (Day 0), on Days 1, 3, 7, 14 and at unscheduled deaths.

Necropsy:
At the end of the fourteen day observation period, the animals were euthanised by exsanguination under anaesthesia (RELEASE 300mg/ml) and gross macroscopic examination was performed. All animals were subject to a gross necropsy which included a detailed examination of the abdominal and thoracic cavities. Special attention was given to the respiratory tract for macroscopic signs of irritancy or local toxicity.

Statistics:

The four-hour LC50 values were calculated using SPSS software and a log/probit method.

Results and discussion

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LC50

Effect level:

2.63 mg/L air (analytical)

Based on:

test mat.

95% CL:

2.17 - 5.23

Exp. duration:

4 h

Effect levels 2

Sex:

male/female

Dose descriptor:

other: LOAEC

Effect level:

480 mg/m³ air (analytical)

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: Clinical signs of respiratory tract irritation, reversible within 24h and a slight body weight loss 24 hours after exposure

Mortality:

A single four hours nose-only exposure of Ethyldiisopropylamine to CRL: (WI) rats strain rat led to the death of 0/10, 1/10, 10/10 and 4/4 rats dosed at a concentration of 0.48, 2.07, 4.15 and 9.16 mg/L, respectively.

Clinical signs:

other: Wet fur was recorded both during and for several hours after exposure whilst fur staining on whole body was recorded on removal from restraint and persisted for several days. In addition, fur staining by the test item was detected during exposure and pers

Body weight:

In all surviving animals of groups 1 and 2, a slight to moderate body weight loss was observed 24 hours after exposure (-9.6% in males and -4.4% in females of group 1 and -25% in males and -14% in females of group 2). Normal bodyweight gain was noted thereafter during the observation period for the surviving animals, with the exception of one male and one female in group 2 where slight bodyweight loss was noted during the first week of the observation period.

Gross pathology:

Dark/red discoloration of the lungs recorded for 10/10 found dead rats at a concentration 4.15 mg/L, was considered to be potentially related to the administration of the test item.
In surviving animals dosed at 0.48 and 2.07 mg/L no macroscopic observations were seen at the termination on Day 14.

Any other information on results incl. tables

The mortality data are summarised as follows:

Group Number	Mean Achieved (mg/L)	Male Deaths	Female Deaths	Total Deaths
0.1	9.19	2/2	2/2	4/4
1	0.48	0/5	0/5	0/10
2	2.07	0/5	1/5	1/10
3	4.15	5/5	5/5	10/10

Applicant's summary and conclusion

Interpretation of results:

Category 3 based on GHS criteria

Conclusions:

The acute inhalation median lethal concentrations (4hr LC50) (and 95% confidence limits) of Ethyldiisopropylamine, in Wistar CRL:(WI) strain rats, were calculated to be 2.63 (2.17 – 5.23) mg/L (all animals).

Executive summary:

This study was performed to assess the acute inhalation toxicity of ethyldiisopropylamine. The method used was designed to meet OECD guideline 403 (07 September 2009). Group 0.1 of two male and two female and groups 1 to 3 each of five female and five male CRL: (WI) Wistar rats were exposed for four hours using a nose-only exposure system to vapours of ethyldiisopropylamine. The exposure was followed by a fourteen day observation period. Vapour concentrations were measured using a calibrated Miran 1A CVF gas analyzer. Clinical observations and bodyweights were recorded throughout the study. At deaths and the end of the scheduled period the animals were sacrificed and subjected to a gross examinationpost mortem. No control group was used in this study. The exposure of rats to 0.48, 2.07, 4.15 and 9.19 mg/L Ethyldiisopropylamine led to the death of 0/10, 1/10, 10/10 and 4/4 rats, respectively. Wet fur and fur staining were commonly recorded on the day of exposure. These observations were considered to be related to the restraint and exposure procedures and, in isolation, were considered not to be biologically significant. Slight to severe laboured respiration was noted on day of exposure in the animals exposed to 0.48 mg/L. No clinical signs were recorded in these animals from the following day after exposure. At the concentration of 2.07 mg/L, one female died during the exposure. Slight to severe laboured and noisy respiration were noted for the exposed animals on day of exposure. In addition, sneezing, decreased activity, weak condition and eyes partially closed were observed in animals during and/or shortly after the exposure. In females, slight continues tremors and prostration were noted on Day 0. All clinical signs ceased in surviving animals from Day 3. All animals exposed to 4.15 and 9.19 mg/L died during the first two hours and the first hour of the exposure, respectively. In all surviving animals exposed to 0.48 and 2.07 mg/L, a slight to moderate body weight loss was observed 24 hours after exposure (-9.6% in males and -4.4% in females at 0.48mg/L and -25% in males and -14% in females at 2.07 mg/L). Normal bodyweight gain was noted thereafter during the observation period for the surviving animals, with the exception of one male and one female exposed to 2.07 mg/L, where slight bodyweight loss was noted during the first week of the observation period. Non collapsed lung was observed in dead animals from the sighting exposure dosed at 9.16 mg/L. Dark/red discoloration of the lungs recorded for 10/10 found dead rats at a concentration 4.15 mg/L, was considered to be potentially related to the administration of the test item. In surviving animals dosed at 0.48 and 2.07 mg/L no macroscopic observations were seen at the termination on Day 14. The acute inhalation median lethal concentrations (4hr LC50) (and 95% confidence limits) of ethyldiisopropylamine, in Wistar CRL:(WI) strain rats, were calculated to be:

All animals:            2.63 (2.17 – 5.23) mg/L

Male only:              2.96 (1.64 – 9.05) mg/L

Female only:           2.46 mg/L