Registration Dossier

Administrative data

Description of key information

LC50, Inhalation, 4 hours (rat) = 11726 ppm

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via inhalation route

Link to relevant study records
Reference
Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
15 August 2002 - 14 January 2004
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to OECD and US EPA test guidelines, and in compliance with GLP; on this basis the result is considered reliable without restriction.
Qualifier:
according to
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
Qualifier:
according to
Guideline:
EPA OPPTS 870.1300 (Acute inhalation toxicity)
GLP compliance:
yes (incl. certificate)
Test type:
standard acute method
Limit test:
no
Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Route of administration:
inhalation: vapour
Type of inhalation exposure:
nose only
Vehicle:
air
Analytical verification of test atmosphere concentrations:
yes
Duration of exposure:
4 h
Concentrations:
Group 1: Target 25,000 ppm, Analytical 26,580 ppm, Nominal 29,400 ppm
Group 4: Target 5,000 ppm, Analytical 5,173 ppm, Nominal 6,220 ppm
No. of animals per sex per dose:
5 males and 5 females per dose
Control animals:
no
Sex:
male/female
Dose descriptor:
LC50
Effect level:
11 726 ppm
Based on:
test mat.
95% CL:
9 054 - 15 186
Exp. duration:
4 h
Mortality:
26,580 ppm: 10/10 died
5,173 ppm: 0/10 died
Clinical signs:
other: During exposure, labored breathing or gasping was reported during the last hour of each exposure. Immediately following the exposures, clear or red nasal discharge, excessive salivation, labored breathing and mosit rales were observed. The severity and
Body weight:
All surviving animals gained weight (or did not lose weight) during both weeks of observation.
Gross pathology:
One or more rats from both exposure levels had red discoloration of the lungs. Fluid was present in the lungs of one male fromt he higher level exposure of 26,580 ppm. Microscopically, in the unscheduled deaths, the discoloration was due to vascular congestion which is commonly seen in rats not found dead or moribund rior to post mortem examination. The scattered red foci were agonal hemorrhages. All of the rats in the 26, 580 ppm group had bronchiolar lesions consisting of desquamated epithelium, bronchiolar/peribronchiolar acute/subacute inflammation and/or intraluminal debris; the severity of the findings ranged from slight to moderate. Alveolar/intralveolar macrophages (minimal to moderate) normally present in lungs, were most numerous in several of these rats. Other findings in the lungs ocurred sporadically and were not considered to be test substance related. these findings have been seen in rats of this strain and age used in similar studies conducted at this facility.
Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
The 4-hr acute inhalation toxicity in rats was 11,726 ppm.
Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LC50
Value:
83 900 mg/m³
Quality of whole database:
The key study, referred to above, was considered reliable without restriction; the overall database is therefore considered to be of acceptable quality.

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

An acute inhalation toxicity study was conducted (Huntingdon Life Sciences, 2004) to assess the toxicity of 2-Bromo-3,3,3-trifluoropropene following a single 4-hour exposure by the inhaled route. The study was performed according to OECD guideline 403 and US EPA OPPTS 870.1300, and in compliance with GLP.

Ten rats (5 rats per sex) were initially exposed at a target concentration of 25000 ppm (analytical concentration = 26580 ppm); a subsequent group of ten rats were exposed to a target concentration of 5000 ppm (analytical concentration = 5173 ppm). All animals exposed at 26580 ppm were found dead or were euthanized due to poor condition on the day after exposure. All animals exposed at 5173 ppm survived to the end of the 14-day post-exposure observation period.

The LC50 for 2-Bromo-3,3,3-trifluoropropene following a 4-hour inhalation exposure was determined to be 11726 ppm.

Note: Inhalation LC50= 11726 ppm = 83.9 mg/L (83,900 mg/m3) (assuming volume of 1 mole of gas = 24.45 at 25°C and 1 atm, and molecular weight = 174.947).

Acute toxicity testing was not performed by the oral or dermal exposure routes. On the basis that the substance has a boiling point close to (but slightly lower than) body temperature it was considered that oral administration could result in rapid evaporation or boiling of the substance shortly after ingestion which could cause physical damage to the test animals without giving a useful indication of any toxic (local or systemic) effects; the study was therefore waived on ethical grounds. It was considered that the substance would rapidly evaporate following dermal contact and as such it was considered that consistent test material concentrations could not be maintained during the typical dermal exposure period (24 hours). The test was therefore waived on scientific grounds.

Justification for selection of acute toxicity – inhalation endpoint

Selected study was conducted according to modern test guidelines (OECD and US EPA) and in compliance with GLP, so is considered reliable.  A second (supporting) study was available, but only considered exposure over 30 minutes which is significantly less than the exposure duration for this endpoint.

Justification for classification or non-classification

No information regarding oral or dermal administration of the substance are available. Due to the physical nature of the substance (a highly volatile liquid) it is expected that no significant exposure will occur by either of these routes.

2-Bromo-3,3,3-trifluoropropene is a liquid at room temperature, boiling at approximately 34°C; it is anticipated that under any forseeable use conditions that inhaled exposure will involve the substance in a vapour state. The LC50 of 2-bromo-3,3,3-triflouoropropene is 83.9 mg/L; acute toxicity category 4 for vapours applies where the LC50 is 20 mg/L or lower; on this basis the substance does not meet the classification criteria for acute toxicity according to the CLP Regulation.

Exposure to 2-bromo-3,3,3-triflouropropene appears to induce temporary depression of the central nervous system (note decreased activity seen after exposure to the higher test concentration in Huntingdon Life Sciences study (2004), and temporary anaesthesia seen following the 30-minute exposure study (Lovelace, 1999). On the basis of this sub-lethal effect it is considered that a classification for Specific Target Organ Toxicity (Single Exposure), Category 3 should be applied. The appropriate hazard phrase is H336 "May cause drowsiness or dizziness".