Registration Dossier

Toxicological information

Acute Toxicity: inhalation

Currently viewing:

Administrative data

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1995-09-21 to 1995-12-29
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1995
Report date:
1995

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
EPA OPP 81-3 (Acute inhalation toxicity)
Version / remarks:
(November 1984)
Deviations:
no
Qualifier:
according to guideline
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
Version / remarks:
(May 12, 1981)
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method B.2 (Acute Toxicity (Inhalation))
Version / remarks:
(29 December 1992)
Deviations:
no
GLP compliance:
yes
Test type:
acute toxic class method
Limit test:
no

Test material

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories, Kingston, NY
- Age at study initiation: approximately 7 and 9 weeks
- Weight at study initiation: males: 216 ± 7.3 g; females 223 ± 8.6 g
- Fasting period before study: no
- Housing: individually in stainless steel suspended cages with Deosorb indirect bedding
- Diet: Purina Laboratory Rodent Chow 5001 ad libitum
- Water: fresh tap water ad libitum
- Acclimation period: 5 days prior to study start

ENVIRONMENTAL CONDITIONS
- Temperature: 20 to 20.5 °C on an average
- Humidity: 50 to 56 % R.H
- Air changes not indicated
- Photoperiod: 12 hours fluorescent light/12 hours dark

Administration / exposure

Route of administration:
inhalation: dust
Type of inhalation exposure:
nose only
Vehicle:
other: unchanged (no vehicle)
Details on inhalation exposure:
The test animals were exposed to disodium persulfate in a 11 litre ADG nose-only exposure chamber made of anodized aluminium and operated dynamically. The chamber air was exhausted from the bottom of the chamber and passed through an orifice tube system which continuously monitor airflow and then through a commercial filter box. The filter box was connected to a line leading to additional filters and an exhaust fan on the roof. The exhaust operated at a flow rate of 38.6 litres per minute, creating a slight negative pressure in the chamber. The calculated 99 % equilibrium time for the chamber at a flow rate of 38.6 litres per minute was 1.3 minutes (equivalent to 1 "air change" every 17 seconds). This chamber size and airflow rate is considered adequate to maintain the oxygen above 19 %. Chamber airflow measurements were recorded at 30 minute intervals. The entire exposure system and primary exhaust filter were contained in a fume hood.
The exposure was conducted for 4 hours. At the end of the exposure, the chamber was cleared for approximately 30 minutes by drawing room air through it at the same flow rate (38.6 litres per minute) prior to removing the animals.
The test animals were assigned to and housed in individual polycarbonate nose-only tubes during the exposure. The tube position assignment ensured equal distribution of both sexes around the chamber.
Analytical verification of test atmosphere concentrations:
yes
Duration of exposure:
4 h
Concentrations:
Gravimetric concentration: 5.10 mg/L
Nominal concentration: 19.0 mg/L
No. of animals per sex per dose:
5 males/5 females
Control animals:
no
Details on study design:
The test material was ground using a micro-mill to ensure the test material was respirable as possible to the test species.
The test material was packed into large dust cups and the desiccated overnight. The test atmosphere was generated using a BGI Wright Dust Feeder II. Breathing Grade compressed air was metered to the dust feeder through 1/4 inch Teflon tubing by a Matheson 605 rotameter. The dust feeder back pressure was monitored by a Marshalltown back pressure gauge. The test material was made airborne by compressed air dispersing the material into the exposure chamber. The concentration of the test atmosphere was controlled by the delivery rate setting of the Wright dust feeder.
Statistics:
Particle size distribution was determined by log-probability plotting of the data and subsequent determination of the mass median aerodynamic diameter, geometric standard deviation and other particle size parameters from the data plots. The LC50 and 95 % confidence limits was determined by a suitable logit or probit analysis.

Results and discussion

Effect levelsopen allclose all
Key result
Sex:
male/female
Dose descriptor:
LC50
Effect level:
> 5.1 mg/L air
Exp. duration:
4 h
Sex:
male
Dose descriptor:
LC0
Effect level:
5.1 mg/L air
Exp. duration:
4 h
Mortality:
All animals survived to study termination.
Clinical signs:
other: Clinical signs observed during the study included chromodacryorrhea, chromorhinorrhea, decreased faeces, decreased locomotion, dyspnoea, nasal discharge and oral discharge. All of these signs resolved by day 2 of the observation period.
Body weight:
All animals gained weight during the study.
Gross pathology:
No gross internal lesions were noted during necropsy.
Other findings:
None

Any other information on results incl. tables

The MMAD's ranged from 4.28 to 5.35 micrometers (µm) with a geometric standard deviation ranged from 2.61 to 2.38 µm. The fraction of particles less than or equal to 1 µm in mass aerodynamic diameter, based on the log-probability graphs, ranged from 0 % to 5.6 %. The fraction of particles less than or equal to 10 µm in mass aerodynamic diameter, based on the log probability graphs, ranged from 76.5 to 81.2 %.

Table 1: Particle size analysis:

Sample number: E03C;

Exposure time: 64 minutes;

Percent

Cutoff (microns)

 5.6

 1.00

 15.9

 1.64

 25.0

 2.25

 50.0

 4.28

 81.2

 10.00

 84.1

 11.16

 90.5

 15.00

 Geometric standard deviation: 2.61;

Table 2: Particle size analysis:

Sample number: E07C;

Exposure time: 190 minutes;

Percent

Cutoff (microns)

 -0.5

 1.00

 15.9

 2.25

 25.0

 2.98

 50.0

 5.35

 76.5

 10.00

 84.1

 12.70

 88.3

 15.00

 Geometric standard deviation: 2.38

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
LC50 and LC0 values of greater than 5.1 mg/L and 5.1 mg/L, respectively, were determined. Thus, the test material was not classified and labelled for acute toxicity via the inhalation route according to Regulation 1272/2008/EC (CLP).
Executive summary:

Disodium persulfate was tested for inhalation toxicity in the rat in a study performed according to EPA OPP 81-3 guideline. A group of five male and five female Sprague Dawley rats was exposed to disodium persulfate for 4 hours at a mean concentration of 5.1 mg/L in a dynamically-operated, nose-only inhalation exposure chamber. Gravimetric airborne test material samples were taken frequently during the exposure. Particle size samples were taken twice during the exposure. Observations for toxicity and mortality were performed frequently during the exposure and upon removal of the rats from the chamber, one hour post-exposure and daily thereafter for 14 days. All animals survived to study termination. Clinical signs observed during the study resolved by day 2 observations. All animals gained weight during the study. No gross internal lesions were noted during necropsy. Under the conditions of the study, LC50 and LC0 values of greater than 5.1 mg/L and 5.1 mg/L, respectively, were determined.