Sodium N-lauroylsarcosinate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 Apr - 11 May 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1300 (Acute inhalation toxicity)

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Sodium N-lauroylsarcosinate

EC Number:

205-281-5

EC Name:

Sodium N-lauroylsarcosinate

Cas Number:

137-16-6

Molecular formula:

C15H29NO3.Na

IUPAC Name:

sodium [dodecanoyl(methyl)amino]acetate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld, Germany
- Age at study initiation: approximately 10-12 weeks
- Weight at study initiation: 324 g (males) and 209 (females)
- Fasting period before study: during exposure to the test substance
- Housing:
Before exposure:
Group housing of five animals per sex per cage in labelled Macrolon cages (type IV; height 18 cm) containing sterilised sawdust as bedding material and paper as cage-enrichment
After exposure: Group housing as described above, except that a paper sheet was introduced into the cage covering the bedding and cage enrichment to prevent suffocation in case of bad health condition. At the end of the Day of exposure the paper sheet was removed.
- Diet: pelleted rodent diet except during exposure to the test substance, ad libitum
- Water: tap water except during exposure to the test substance, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.0 ± 3.0 (actual range: 19.8 – 21.5)
- Humidity (%): 40-70 (actual range: 34 – 60)
- Air changes (per hr): approximately 15
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose only

Vehicle:

other: no vehicle

Details on inhalation exposure:

EXPOSURE CHAMBER:
The design of the exposure chamber is based on the flow past nose-only inhalation chamber. The chamber consisted of three or four animal sections with eight animal ports each. Each animal port had its own atmosphere inlet and exhaust outlet. The animals were placed in restraining tubes and connected to the animal ports. The number of animal sections and number of open inlets were adapted to the air flow in such a way that at each animal port the theoretical air flow was at least 1 L/min, which ensures an adequate oxygen supply to the animals. The main inlet of the test atmosphere was located at the top section and the main outlet was located at the bottom section. The direction of the flow of the test atmosphere guaranteed a freshly generated atmosphere for each individual animal.
All components of the exposure chamber in contact with the test material were made of stainless steel, glass, rubber or plastic. To avoid exposure of the personnel and contamination of the laboratory the exposure chamber was placed in a fume hood, which maintained at a slight negative pressure.

TEST ATMOSPHERE GENERATION:
The test substance was fed to a stream of pressurized air (mean air flow 27.6 l/min at 5 mg/L, 19.1 l/min at 1 mg/L, 38.6 l/min at 0.55 mg/L and 110.6 l/min at 0.055 mg/L) by means of a spiral feeder and a micronizing jet mill, which was subsequently was passed through a cyclone, allowing larger particles to settle, before it entered the exposure chamber. The rotation speed of the feeder was varied to obtain the desired exposure concentration.
From the exposure chamber the test atmosphere was passed through a filter before it was released to the exhaust of the fume hood.

TEST ATMOSPHERE CHARACTERISATION:
Nominal concentration:
The nominal concentration was calculated by dividing the amount of test substance used by the volume of pressurized air (average air flow times exposure time) entering the exposure chamber used for exposure of the animals.

Actual concentration:
The actual concentration was determined five times during exposure at 5 or 1 mg/L, nine times at 0.55 mg/L and seven times at 0.055 mg/L. Samples were drawn from the test atmosphere through a tube mounted in one of the free animal ports of one of the middle sections of the exposure chamber. Samples were drawn through a glass fiber filter. The collected amount of the test substance in the air sample was measured gravimetrically. Sample volumes were measured by means of a dry gas meter.

Subsequently the mean concentrations with the standard deviation were calculated.

Particle size characterisation:
The particle size distribution was representatively characterized twice during exposure. The samples were drawn (2 L/min) from the test atmosphere through a tube mounted in one of the free animal ports of one of the middle sections of the exposure chamber. The samples were collected with an 8 stage Marple personal cascade impactor containing fiber glass filters and a fiber glass back-up filter. Amounts of test substance collected were measured gravimetrically. Subsequently the Mass Median Aerodynamic Diameter (MMAD) and the Geometric Standard Deviation (GSD) were determined.

Stability monitoring:
The opacity of the test atmosphere at the highest concentrations was expected to exceed the maximum that could be monitored by means of an aerosol monitoring system. An indication of the stability of the test atmosphere was obtained from the concentration measurements, which were equally distributed over time. For the lowest concentration, the opacity of the test atmosphere was monitored by means of a real time aerosol monitoring system. Data obtained with this system were used to illustrate the stability of the aerosol during exposure of the animals.

Temperature and relative humidity:
The temperature and relative humidity were measured with a humidity and temperature indicator and were recorded after the animals were placed in the experimental set-up and at 30 minute intervals after initiation of the exposure. The probe was inserted in a tube mounted in one of the free animal ports of the middle section of the exposure chamber. The temperature of the atmosphere was between 18.1 and 21.3°C and relative humidity was between 23 and 41%. These conditions were considered appropriate for this relatively short 4 hours exposure duration.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

Initially, five animals of each sex were exposed for 4 hours to a target concentration of the test substance of 5 mg/L. Based on mortality, further animals were dosed at 1 mg/L (both sexes), and at 0.5 and 0.05 mg/L using the most sensitive sex (males) only.

No. of animals per sex per dose:

5 males and 5 females at 5.5 mg/L
5 males and 5 females at 1.1 mg/L
5 males at 0.5 and 0.05 mg/L

Control animals:

no

Details on study design:

- Other examinations performed:
Mortality/Viability: Twice daily. Animals showing pain, distress or discomfort, which was considered not transient in nature or was likely to become more severe, were sacrificed for humane reasons. The time of death was recorded as precisely as possible.

Clinical signs (During exposure): Three times during exposure for mortality, behavioural signs of distress and effects on respiration.

Clinical signs (After exposure): Twice (at 1 and at 3 h after exposure) on the day of dosing (Day 1) and once daily thereafter, until Day 15. The symptoms were graded according to fixed scales and the time of onset, degree and duration were recorded:
Maximum grade 4: grading slight (1) to very severe (4)
Maximum grade 3: grading slight (1) to severe (3)
Maximum grade 1: presence is scored (1).

Body weights: Days 1 (pre-administration), 2, 4, 8 and 15 and at death (if found dead or sacrificed after Day 1).

Necropsy: The moribund animals and animals surviving to the end of the observation period were sacrificed by an intraperitoneal injection with Euthasol ® (AST Farma BV, Oudewater, The Netherlands) and subsequently exsanguinated. All animals assigned to the study were subjected to necropsy and descriptions of all internal macroscopic abnormalities were recorded. Particular attention was given to any changes in the respiratory tract.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 0.05 - < 0.5 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Mortality:

5 mg/L: 5/5 males and 5/5 females died (at 1-2 h post-dose)
1 mg/L: 5/5 males and 5/5 females died (at 1-2 days post-dose)
0.5 mg/L: 4/5 males died (at 1-2 days post-dose)
0.05 mg/L: 0/5 males died

Clinical signs:

other: During exposure: 1 mg/L: most animals showed laboured respiration. No clinical signs were noted during exposure at 5, 0.5 and 0.05 mg/L. After exposure: 5 mg/L: No clinical signs noted prior to death/sacrifice. 1 mg/L: Lethargy, flat/hunched posture, la

Body weight:

Significant weight loss was observed for the single surviving male at 0.5 mg/L (No. 25) between Days 1 and 4. Body weight gain of males at 0.05 mg/L was within the range expected for rats of this strain and age used in this type of study.

Gross pathology:

5 mg/L : Red foci on the lungs, red contents of the small intestines/ileum, red discolouration of the thymus and or small intestines among most animals.
1 mg/L: Red foci on the lungs or red discolouration of the lungs in all animals.
0.5 mg/L: Red foci on the lungs and/or thymus and/or red discolouration of the lungs among most males.
0.05 mg/L: No abnormalities noted.

Other findings:

The concentration measurements, distributed over time, showed that the substance was sufficiently stable. At 0.05 mg/L data was obtained from the opacity monitor and showed that the aerosol was sufficiently stable. The short drops in opacity were caused by adjustments to the generation equipment and were considered not to have affected the exposure level.

Any other information on results incl. tables

Table 1. Test atmosphere characterisation.

Target concentration (mg/L)	Actual concentration (mg/L; mean ± sd)	Nominal concentration (mg/L; mean)	Generation efficiency (%)
5	5.4 ± 0.6	15.4	35
1	1.2 ± 0.1	4.2	29
0.5	0.6 ± 0.2	2.9	21
0.05	0.06 ± 0.01	0.05	83

Table 2. Particle Size.

Target concentration (mg/L)      (measurement no.)	MMAD	Gsd
5                             (1)	5.8	3.2
(2)	6.2	2.6
1                             (1)	3.5	4.4
(2)	3.8	4.0
0.5                          (1)	2.5	2.5
(2)	3.2	3.4
0.05                        (1)	4.1	2.4
(2)	4.6	2.9

MMAD: Mass Medium Aerodynamic Diameter

gsd: geometric standard deviation

Table 3. Table for acute inhalation toxicity.

Target concentration [mg/L air]	Toxicological results*	Duration of clinical signs	Time of death	Mortality (%)
Males
5	5/5/5	---	1-1.5 h after start of exposure	100
1	5/5/5		2 h after start of exposure	100
0.5	4/5/5		Day 1-2	80
0.05	0/0/5		-	0
Females
5	5/5/5	---	2 h after start of exposure	100
1	5/3/5		2-4.5 h after start of exposure	100
LC50 0.05-0.5 mg/L air

*first number = number of dead animals

second number = number of animals with clinical signs

third number = number of animals used

Applicant's summary and conclusion

Interpretation of results:

other: Acute tox. Inhalation 2, H330. Classification according to Regulation (EC) No 1272/2008 (CLP/EU GHS).

Conclusions:

CLP: Acute Tox. 2, H330