Ethylene diformate

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:

2012

Report date:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

yes

Remarks:

(MMAD exceeds range given in test guideline (1-4 µm)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.2 (Acute Toxicity (Inhalation))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

The Department of Health of the Government of the United Kingdom

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Ethylene diformate

EC Number:

211-077-7

EC Name:

Ethylene diformate

Cas Number:

629-15-2

Molecular formula:

C4H6O4

IUPAC Name:

2-(formyloxy)ethyl formate

Details on test material:

- Name of test material (as cited in study report): Ethylene Glycol Diformate
- Physical state: pale yellow liquid
- Analytical purity: minimum 80% (w/w)
- Lot/batch No.: 13082
- Expiration date of the lot/batch: 28 June 2013
- Storage condition of test material: room temperature in the dark

Test animals

Species:

rat

Strain:

other: RccHan™:WIST

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK Ltd., Oxon, UK
- Age at study initiation: 8 to 12 weeks
- Weight at study initiation: 200-350 g
- Housing: animals were housed in groups of five by sex in solid-floor polypropylene cages with stainless steel lids, furnished with softwood flakes and provided with environmental enrichment items: wooden chew blocks and cardboard "fun tunnels" (Datesand Ltd., Cheshire, UK).
- Diet: Harlan 2014C Rodent Diet (Harlan Laboratories UK Ltd., Oxon, UK), ad libitum
- Water: main drinking water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-25
- Humidity (%): 30-70
- Air changes (per hr): at least 15
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose only

Vehicle:

clean air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: cylindrical exposure chamber
- Exposure chamber volume: 30 L (28 cm diameter x 50 cm high)
- Method of holding animals in test chamber: animals were individually held in a tapered, polycrbonate restraining tube fitted onto a single tier of the exposure chamber and sealed by means of a rubber "O" ring.
- Source and rate of air: compressed air was supplied by means of an oil free compressor and passed through a water trap and respiratory quality filters before it was introduced to the nebuliser. The chamber flow rate was maintained at 60 L/min providing 120 air changes per hour.
- System of generating aerosols: the test item was aerosolised using a glass concentric jet nebuliser (Radleys, Saffron Walden, UK).
- Method of particle size determination:the particle size of the generated atmosphere inside the exposure chamber was determined four times during the exposure period using a Marple Personal Cascade Impactor (Westech IS Ltd., Beds., UK).
- Temperature, humidity, pressure in air chamber: temperature, relative humidity and oxygen levels were measured by an electronic thermometer/humidity meter (Hanna Instruments Ltd, Beds, UK) or oxygen analyser (Servomex Ltd, Crowborough, UK) located in a vacant port in the animals’ breathing zone of the chamber. During exposure, temperature was always 20 °C, humidity was between 76 and 80% and oxygen concentration 20.8%. The chamber was maintained under negative pressure (not specified).

TEST ATMOSPHERE
- Brief description of analytical method used: the actual concentration of the test item was measured off-line by gas chromatography (GC).
- Samples taken from breathing zone: yes

TEST ATMOSPHERE
- Particle size distribution: Inhalable fraction (% < 4 µM) 44.1
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.): 4.6 µM / 2.57

Analytical verification of test atmosphere concentrations:

yes

Remarks:

GC

Duration of exposure:

4 h

Concentrations:

5.05 mg/L (mean achieved concentration)
18.2 mg/L (nominal concentration)

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: bodyweights were recorded on arrival, prior to treatment on the day of exposure and on Days 1, 3, 7 and 14.
- Necropsy of survivors performed: yes
- Other examinations performed: animals were observed for clinical signs and the respiratory tract was subjected to a detailed macroscopic examination for signs of irritancy or local toxicity.

Results and discussion

Preliminary study:

In a preliminary study, two rats (one male, one female) were exposed to an atmosphere of the test item at a mean achieved atmosphere concenration of 2.83 mg/L for approx. 4 hours. No significant effects were noted in either animal.

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 5.05 mg/L air (analytical)

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: No animal died at the limit dose of 5.05 mg/L. The concentration of particles < 4 µm (respirable fraction) was approx. 2.23 mg/L.

Mortality:

No mortality occurred during the study period.

Clinical signs:

other: The following abnormalities were detected (during exposure): increased respiratory rate; (one day after exposure): increased respiratory rate and hunched posture. All animals recovered during Days 3 to 4 after exposure. Hunched posture, pilo erection, re

Body weight:

Four males and four females exhibited weight losses on the first day post-exposure. With the exception of two female animals which showed no bodyweight gain from either days 1 to 3 or 3 to 7 post-exposure, reasonable bodyweight development was noted in all animals during the remainder of the recovery period.

Gross pathology:

No macroscopic abnormalities were detected in any animal at necropsy.

Any other information on results incl. tables

Table 1. Mean achieved atmosphere concentration

Atmosphere concentration
Mean achieved (mg/L)	Standard deviation	Nominal (mg/L)
5.05	0.15	18.2

 

Table 2. Characteristics of the achieved atmosphere

Mean achieved atmosphere concentration (mg/L)	Mass median aerodynamic diameter (µm)	Inhalable fraction (% < 4µm)	Geometric standard derivation
5.05	4.60	44.1	2.57

 

Table 3. Results of the acute inhalation study: Mortality

Mean achieved atmosphere concentration (mg/L)	Deaths
	Male	Female	Total
5.05	0/5	0/5	0/10

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

CLP: not classified
DSD: not classified