Manganese alumina pink corundum

Endpoint summary

Description of key information

Acute oral lethal dose (LD 50): > 2200 mg/kg bw. 
Acute toxicity, inhalation:  LC50 > 6.2 mg/L (MMAD: 1.8 µm (GSD: = 3.0))

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Minor deviation from the guideline without an effect on the results: - According to the guideline, the surviving animals should be weighed and then sacrificed at the end of the test. In this study, the animals were weighed before a fasting period, which was carried out 16 h before scarification of the animales.

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

1987-02-24

Deviations:

yes

Remarks:

, see "rational for reliability"

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr. K. Thomae GmbH, D- W7950 Biberach, FRG
- Age at study initiation: Young adult animals
- Weight at study initiation: Mean weight males: 188 g (186 g - 192 g); mean weight females: 189 g (185 g - 194 g)
- Fasting period before study: The animals were given no feed at least 16 hours before administration, but water was available ad libitum.
- Housing: Single housing; Stainless steel wire mesh cages, Type DK-III (Becker & Co., Castrop-Rauxel, FRG); No bedding in the cages; Sawdust in the waste traye
- Diet (ad libitum): Kliba-Labordiaet 343, Klingentalmuehle AG, CH-4303 Kaiseraugst, Switzerland
- Water (ad libitum): Tap water
- Acclimation period: At least 1 week

ENVIRONMENTAL CONDITIONS
- Temperature: 20 - 24 °C
- Relative humidity: 30 - 70 %
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 22.000 g /100 ml
- Justification for choice of vehicle: Aqueous formulation corresponds to the physiological medium.

MAXIMUM DOSE VOLUME APPLIED: 10 ml/kg

- Rationale for the selection of the dose: Based on the physical and chemical characteristics of the test substance no pronounced acute oral toxicity was expected. Therefore a dose of 2200 mg/kg body weight has been chosen for the study.

Doses:

2200 mg/kg

No. of animals per sex per dose:

5 males / 5 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Individual body weights were determined shortly before application (Day 0), weekly thereafter and at the end of the study (before fasting period). Recording of signs and sympotms several times on the day of administration, at least once each workday for the individual animals.A check was made twice each workday and once on saturdays, sundays and on public holidays for general observations and for any dead or moribund animals.
- Necropsy of survivors performed: Yes
Necropsy at the last day of the observation period. Withdrawal of food at least 16 hours before killing with CO2; then necropsy with gross pathology examination. Necropsy of all animals that died before as early as possible.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 200 mg/kg bw

Based on:

test mat.

Remarks on result:

other: 1% significance level

Mortality:

No mortality occurred.

Clinical signs:

other: Signs of toxicity have not been noted.

Body weight:

other body weight observations

Remarks:

The expected body weight gain has been observed in the course of the study.

Gross pathology:

No abnormalities were noted at necropsy of animals sacrificed at the end of the study.

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of this study the acute oral median dose (LD50) of the test material was found to be greater than 2200 mg/kg body weight for the male and female animals.
According to the EC Regulation No. 1272/2008 and subsequent regulations, the test item is not classified as acute toxic by the oral route.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

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:

1991-08-15 to 1991-08-29

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Minor deviations from the guideline without effects on the results: - No acclimatisation period was stated. - According to the guideline, an inhalation equipment to substain a dynamic air flow of 12 to 15 air changes per hour should be used. In this report it was only stated that the air flow was 1, 500 l/h. - According to the guideline, the duration of the exposure should be at least 4 hours after equilibrium of the chamber concentration. In this study it was not stated if exposure started after an equilibration period. -According to the guideline the equipment for measuring temperature should be stated, which was not done in this study.

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Version / remarks:

1981-05-12

Deviations:

yes

Remarks:

see "rational for reliability"

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr. K. Thomae GmbH, D-W7950 Biberach, FRG)
- Age at study initiation: approx. 8 - 9 weeks
- Weight at study initiation: mean weight males: 271 +/- 7.8 g; mean weight females: 195 +/- 9.7 g
- Housing: Rats were housed singly in cages type DK III of becker, without bedding.
- Diet (ad libitum): KLIBA rat/mouse/hamster laboratory diet 24-343-4 10 mm pellets, Klingentalmühle AG, CH-4303 Kaiseraugst, Switzerland during the post-exposure observation period.
- Water (ad libitum): Drinking water during the post-exposure observation period.

ENVIRONMENTAL CONDITIONS
- Temperature: 20 - 24 °C
- Relative humidity: 30 - 70 %
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

inhalation: dust

Type of inhalation exposure:

nose/head only

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Head-nose inhalation system INA 20 (glass-steel construction, BASF Aktiengesellschaft, volume V approx. 55 l): the animals were restrained in tubes and their snouts projected into the inhalation chamber.

- System of generating particulates/aerosols: The aerosol was produced with a dosing-wheel dust generator (Gericke/BASF) and compressed air. A glass cyclonic separator (BASF) was connetced downstream with the generator. An air air flow (supply air) of 1,500 l/h was set. The exposure system was placed in air-conditioned laboratory.
By means of an exhaust air system to pressure ratios in the inhalation system were adjusted in such a way that the amount of exhaust air was about 10 % lower (excess pressure). This ensured that the mixture of test substance and air was not diluted with laboratory air in the breathing zones of the animals.

- Method of particle size determination: 30 minutes after the beginning of the test at the earliest, one sample was taken per test group for the particle size analysis.
Before the sampling, the impactor was equipped with glass-fiber collecting discs and a backup particle filter. The impactor was connected to the pump and the test apparatus, and one sample (9 l) was taken.
The impactor was taken apart, and the collecting discs and the backup particle filter were weighed.
The content of the pre-impactor as well as the amounts of the material adsorbed on the walls of the impactor and in the sampling probe (wall losses) were also determined quantitatively.
Equipment:
-Stack Sampler Mark III (Andersen)
- Vacuum Compressed Air Pump (Millipore)
-Sampling probe (internal diameter 6.9 mm)
- Balance: Sartorius M3P and Mettler AE 240
- Evaluation unit (IBM-PC with software PGA)

- Method of determination of the nominal concentration: The nominal concentration was calculated from the amount of substance consumed and the air flow.

- Temperature, humidity, pressure in air chamber: The humidity in the inhalation system was not measured due to technical reasons. It is assumed that deviations of humidity values from the guideline requirements (especially low humidity in dust aerosol) did not influence the test results, because of the relative short exposure time.
The temperature in the inhalation system was measured continuosly and recorded once.

TEST ATMOSPHERE
- Brief description of analytical method used: Gravimetric determination of the inhalation atmosphere concentration (Equipment: balance: Mettler AT 250). The preweighed filter was placed into the filtration equipment. By means of a vacuum compressed air pump a volume of the dust aerosol was drwan through the filter.
The dust concentration in mg/l was calculated from the difference between the preweight of the filter and the weight of the filter after sampling, with reference to the sample volume of the inhalation atmosphere.
- Samples taken from breathing zone: yes
Apparatus:
- Vacuum compressed air pump (Millipore)
- Filtration equipment with probe, internal diameter: 4 mm, (Millipore)
- Filter: MN 85/90 Bf (d = 4.7 cm)
- Sampling velocity: 1.25 m/s
- Sampling amount: 2 l
-Sampling frequency: 1 sample about hourly

TEST ATMOSPHERE:
- MMAD / GSD: 1.8 µm (GSD: = 3.0)

Analytical verification of test atmosphere concentrations:

yes

Remarks:

see "details on inhalation exposure" above

Duration of exposure:

4 h

Concentrations:

Nominal concentration: 57.4 mg/l
Actual concentration: 6.2 +/- 0.63 mg/l

No. of animals per sex per dose:

5 males / 5 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The body weight of the animals was checked before the beginning of the test, after 7 days and at the end of the observation period. Clinical findings were recorded for each animal separately several times during exposure and at least once on each workday in the observation period. A check for dead animals was made daily.
- Necropsy of survivors performed: Yes
At the end of the 14-day observation perid the animals were sacrificed with CO2 and were subjected to gross-pathological examination.

Statistics:

The statistical evaluation of the dose-response relationship was carried out using FORTRAN program AKPROZ: depending on the data of the dose-response relationship obtained by way of experiment, this program is used to estimate the LC50 or to perform a Probit analysis (FINNEY, D.J. (1971): "Probit Analysis", Cambridge University Press). Estimation of the LC50 will produce types LC50 greater, LC50 about, or LC50 smaller. if the results are Type LC50 greater or LC50 smaller, an additional binominal test is carried out (WITTING, H. (1974): "Mathematical Statistik" B.G. Teubner, Stuttgart, pp. 32 -35), in order to verify these statements statistically, if necessary.
The calculation of the particle size distribution was carried out in the Department of Toxicology of BASF Aktiengesellschaft on the basis of mathematical methods for evaluating particle measurements (DIN 66141: Darstellung von Korngrößenverteilungen, DIN 66151: Partikelgrößenanalyse (Beuth-Vertrieb GmbH, D-W1000 Berlin 30 and D-5000 Köln 1).

Key result

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 6.2 mg/L air (analytical)

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: The statistical reliability is 99 %.

Mortality:

No deaths occurred.

Clinical signs:

other: Clinical examination showed accelerated respiration in all animals during the exposure period. No abnormalities were detected post exposure besides a discolouration of the fur due to the test substance after exposure on exposure day.

Body weight:

Body weight gain was slightly retarded in male and female animals in the first post exposure week but recovered in the second.

Gross pathology:

During necropsy no pathologic findings were noted.

Interpretation of results:

GHS criteria not met

Conclusions:

No mortality occured at the limit concentration of 6.2 mg/l. Therefore the LC50 is > 6.2 mg/l.
According to the EC Regulation No. 1272/2008 and subsequent regulations, the test item is not classified as acute toxic by the inhalation route.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

One acute oral toxicity study according to OECD guideline 401 has been performed. This study indicates that oral LD50 is >2200 mg/Kg bw in rats.

 

For acute inhalation toxicity one animal study has been performed according to OECD TG 403 and which shows no signs of acute toxicity after inhalation exposure to manganese alumina-pink corundum, indicating a LC50 > 6.2 mg/L. No mortalities occured.

 

There are no reliable reports whatsoever on acute dermal toxicity in the public domain. However, the conduct of an acute dermal toxicity study is unjustified as inhalation of the substance is considered as major route of exposure and physicochemical properties of the substance do not suggest a significant rate of absorption through the skin (cf. Annex VIII section 8.5 Column 2 of regulation (EC) 1907/2006). This is underlined by the very low solubility and bioavailability (Herting, G. and Wallinder, O., 2010) of the elements out of this pigment, which can be considered as inert.

Justification for classification or non-classification

Acute toxicity oral:

Under the conditions of this study the acute oral median dose (LD50) of the test material was found to be greater than 2200 mg/kg body weight for the male and female animals. According to the EC Regulation No. 1272/2008 and subsequent regulations, the test item is not classified as acute toxic by the oral route.

 

Specific target organ toxicant (STOT) – single exposure: oral

The classification criteria acc. to regulation (EC) 1272/2008 as specific target organ toxicant (STOT) – single exposure, oral are not met since no reversible or irreversible adverse health effects were observed immediately or delayed after exposure and no effects were observed at the guidance value, oral for a Category 1 classification of 300 mg/kg bw and at the guidance value, oral for a Category 2 classification of 2000 mg/kg bw. No classification required.

 

Acute toxicity inhalation:

No mortality occured at the limit concentration of 6.2 mg/l. Therefore the LC50 is > 6.2 mg/l. According to the EC Regulation No. 1272/2008 and subsequent regulations, the test item is not classified as acute toxic by the inhalation route.

 

Specific target organ toxicant (STOT) – single exposure: inhalation

The classification criteria acc. to regulation (EC) 1272/2008 as specific target organ toxicant (STOT) – single exposure, inhalation dust/mist/fume are not met since no reversible or irreversible adverse health effects were observed immediately or delayed after exposure and no effects were observed at the guidance value, inhalation dust/mist/fume for a Category 1 classification of 1.0 mg/L/4h and at the guidance value, inhalation dust/mist/fume for a Category 2 classification of 5.0 mg/L/4h. Therefore, no classification is required.

Finally, any category 3 classification should primarily be based on human data. However, such classification is also not warranted, since observations on respiratory irritation in test animals (rats) were not observed.