trans-dichloroethylene

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: This study was selected as the key study because the information provided for the hazard endpoint is sufficient for the purpose of classification and labelling and/or risk assessment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

no

Remarks:

The study was conducted according to the guideline in effect at the time of study conduct.

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1300 (Acute inhalation toxicity)

Deviations:

no

Remarks:

The study was conducted according to the guideline in effect at the time of study conduct.

Test guideline 3

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Remarks:

The study was conducted according to the guideline in effect at the time of study conduct.

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: MAFF Japan 59 NohSan No. 4200 Testing Guidelines for Toxicity Studies (1985)

Deviations:

no

Remarks:

The study was conducted according to the guideline in effect at the time of study conduct.

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

trans-dichloroethylene

EC Number:

205-860-2

EC Name:

trans-dichloroethylene

Cas Number:

156-60-5

Molecular formula:

C2H2Cl2

IUPAC Name:

(1E)-1,2-dichloroethene

Details on test material:

- Purity: 99.89%

Test animals

Species:

rat

Strain:

other: Crl:CD®(SD)IGS BR

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: approximately 8 or 9 weeks old
- Weight at study initiation: Males - 233 to 348 grams; Females - 184 to 235 grams
- Housing: Rats were housed either singly or in pairs (sexes separate) in suspended, stainless steel, wire-mesh cages.
- Diet: PMI Nutrition International, Inc. Certified Rodent LabDiet® 5002, ad libitum
- Water: tap water from United Water Delaware, ad libitum
- Acclimation period: 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): targeted to be within a temperature range of 23 ± 1°C
- Humidity (%): 50 ± 10%
- Photoperiod: 12-hour light/12-hour dark cycle

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

other: Houseline nitrogen and air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: stainless steel and glass (NYU style)
- Exposure chamber volume: 150 L
- Method of holding animals in test chamber: rats were placed within wire-mesh cages and exposed whole-body inside the exposure chamber
- Source and rate of air: 37 L/min
- System of generating vapour: Chamber atmospheres were generated by flash evaporation of liquid test substance in nitrogen (N2 flow = 3 L/min). For each exposure, the subject test substance was metered into a heated (90-171°C), glass mixing flask with a Cole Palmer Masterflex® Console Drive pump. Houseline nitrogen was introduced to the heated mixing flask to carry the vapour into the exposure chamber. Houseline air was introduced before the exposure chamber to dilute the atmosphere generated at the flask.
- Temperature and humidity in air chamber: 22 to 26°C and 32 to 55%, respectively

TEST ATMOSPHERE
- Brief description of analytical method used: Chamber atmosphere samples were directly injected into a Hewlett Packard model 6890 Plus Series Gas Chromatograph equipped with a flame ionization detector for analysis at approximately 15-minute intervals during each exposure. Vapour samples were drawn by vacuum pump from representative areas of the chamber where rats were exposed. All samples were chromatographed isothermally at 100°C on a Restek RTX-200 column.
- Samples taken from breathing zone: yes

VEHICLE
- Composition of vehicle (if applicable): Houseline nitrogen and air

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

0, 12300, 22500, 28100 and 34100 ppm

No. of animals per sex per dose:

5

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: Rats were observed for mortality and response to alerting stimuli during the exposure and observed for mortality and clinical signs of toxicity immediately after they were removed from the chambers following exposure. During a 14-day postexposure period, all surviving rats were observed each day for mortality, and were weighed and observed daily for clinical signs of toxicity.
- Necropsy of survivors performed: yes
- All rats were given a complete gross pathological examination of their internal organs including observation of the nasal passages. Representative samples of the liver, kidney, lung, and heart were saved at necropsy. All tissues were processed, embedded in paraffin, cut at a nominal thickness of 5 micrometers, stained with hematoxylin and eosin (H&E) and examined microscopically.

Statistics:

Probit Analysis

Results and discussion

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LC50

Effect level:

24 100 ppm

Based on:

test mat.

95% CL:

19 200 - 26 900

Exp. duration:

4 h

Remarks on result:

other: Diminished or a lack of response to an alerting stimulus observed during exposure at all doses

Effect levels 2

Sex:

male/female

Dose descriptor:

other: NOEL

Effect level:

34 100 ppm

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: for gross and microscopic pathology; highest concentration tested

Mortality:

See Table in Results below. All deaths occurred during exposures. In calculating the LC50, the male and female rat lethality data was combined because there was no apparent sex difference in the lethality response to the tested compound.

Clinical signs:

other: During exposure, rats were prostrate, many had their eyes open, and exhibited a diminished or a lack of response to an alerting stimulus. After the 12300 ppm exposure, rats appeared to recover and resume a normal appearance within about thirty minutes af

Body weight:

Rats that survived the 22500 ppm exposure showed slight weight loss for one day followed by a normal weight-gain rate. Rats exposed to 28100 ppm showed slight to severe weight loss for one day.

Gross pathology:

There were no test substance-related gross observations.

Any other information on results incl. tables

VAPOUR CONCENTRATION	MORTALITY (# deaths/# exposed)
ppm	MALES	FEMALES
Control	0/5	0/5
12300	0/5	0/5
22500	1/5	3/5
28100	3/5	4/5
34100	5/5	5/5

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

This study and the conclusions which are drawn from it fulfil the quality criteria (validity, reliability, repeatability).
LC50 = 24100 ppm

Executive summary:

Groups of 5 male and 5 female Crl:CD^®(SD)IGS BR rats were exposed whole-body to the test item for a single 4-hour exposure period. A control group was treated similarly except for exposure to the test substance. The test atmosphere was generated by flash evaporating the liquid test substance in nitrogen. The concentration was determined by gas chromatographic analysis.  During a 14-day recovery period, rats were weighed and observed for clinical signs of toxicity. All rats underwent gross pathologic examination immediately after death or at the end of the recovery period and the liver, kidney, heart, and lung were evaluated histologically. In calculating the LC₅₀, the male and female rat lethality data was combined because there was no apparent sex difference in the lethality response to the test compound. The LC₅₀ for the test item was 24100 ppm. All deaths occurred during exposures. During each exposure, the rats were prostrate, many had their eyes open, and showed a diminished or lack of response to an alerting stimulus.
After the 12300 ppm exposure, rats appeared to recover and resume a normal appearance within about thirty minutes after the end of the exposure. There were no effects on rat body weights at this concentration. Rats that survived the 22500 ppm exposure showed lethargy and irregular respiration immediately after exposure and showed slight weight loss for one day followed by a normal weight-gain rate. Rats exposed to 28100 ppm of showed weakness immediately after exposure and slight to severe weight loss for one day. There were no test substance-related gross or microscopic observations for the test substance.