Graphite, acid-treated

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13 October 2010 - 18 April 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study was generated according to internationally accepted guidelines.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: Commission Regulation (EC) No. 440/2008, L 142, Annex Part B, 30 May 2008

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: EPA Health Effects Test Guidelines, OPPTS 870.1000 “Acute toxicity testing background”, EPA 712-C-02-189, December 2002

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

GLP according to German Chemikaliengesetz and Directive 2004/9/EC

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Graphite, acid-treated

EC Number:

291-367-8

EC Name:

Graphite, acid-treated

Cas Number:

90387-90-9

Molecular formula:

C(Carbon) + acid + oxidant Not available by EC, (CnX mHX)

IUPAC Name:

carbon

Details on test material:

- Name of test material (as cited in study report): Graphite, acid treated
- Substance type: Inorganic
- Physical state: Solid
- Lot/batch No.: 1706
- Storage condition of test material: Room temperature
- Density: 2.2 g/cm³
- Particle size range: 80 % < 50 mesh

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Species/strain: healthy rats, WISTAR rats Crl: WI(Han) (full barrier)
- Source: Charles River, 97633 Sulzfeld, Germany
- Sex: female, non-pregnant, nulliparous
- Age at study initiation: 9 - 10 weeks old
- Weight at study initiation:
Step 1 / animals no. 1 - 3: 148 – 168 g
Step 2 / animals no. 4 - 6: 151 – 157 g
- Fasting period before study: 16 to 19 hours (access to water was permitted)

HOUSING AND FEEDING CONDITIONS
- Full barrier in an air-conditioned room
- Temperature: 22 +/- 3 °C
- Relative humidity: 55 +/- 10%
- Artificial light, sequence being 12 hours light, 12 hours dark
- Air change: 10 x / hour
- Free access to Altromin 1324 maintenance diet for rats and mice (lot no. 1307)
- Free access to tap water, sulphur acidified to a pH value of approx. 2.8 (drinking water, municipal residue control, microbiological controls at regular intervals)
- The animals were kept in groups in IVC cages, type III H, polysulphone cages on Altromin saw fibre bedding (lot no. 081110)
- Certificates of food, water and bedding are filed at BSL BIOSERVICE
- Adequate acclimatisation period (at least five days, for details see Schedule)

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

cotton seed oil

Remarks:

Sigma, lot no. MKBB7604, expiry date: 01/06/2011

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 2000 mg/kg body weight at a dose volume of 10 mL/kg body weight
- Amount of vehicle (if gavage): 10 mL/kg body weight
- Justification for choice of vehicle: The vehicle was chosen due to its non-toxic characteristics
- Lot/batch no. (if required): MKBB7604

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg body weight

CLASS METHOD
For animals no. 1 and no. 2 of the first step, 1 g of the test item was suspended in the vehicle to gain a final volume of 5 mL and to achieve a dose of 2000 mg/kg body weight at a dose volume of 10 mL/kg body weight.
For animal no. 3 of the first step and the three animals of the second step, 2 g of the test item were suspended in the vehicle to gain a final volume of 10 mL and to achieve a dose of 2000 mg/kg body weight at a dose volume of 10 mL/kg body weight.

Doses:

2000 mg/kg body weight

No. of animals per sex per dose:

3 per step - 2 steps performed

Control animals:

no

Details on study design:

- Duration of observation period following administration:
14 days

- Frequency of observations and weighing:
A careful clinical examination was made several times on the day of dosing (at least once during the first 30 minutes and with special attention given during the first 4 hours post-dose). As soon as symptoms were noticed they were recorded. Thereafter, the animals were observed for clinical signs once daily until the end of the observation period.
The animals were weighed on day 1 (prior to the administration) and on days 8 and 15.

- Necropsy of survivors performed:
yes

- Other examinations performed:
Cageside observations included changes in the skin and fur, eyes and mucous membranes. Also respiratory, circulatory, autonomic and central nervous systems and somatomotor activity and behaviour pattern were examined. Particular attention was directed to observations of tremor, convulsions, salivation, diarrhoea, lethargy, sleep and coma.

Statistics:

Not relevant due to no toxic effects observed in Limit test

Results and discussion

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occured.

Clinical signs:

other: No signs of toxicity have been observed.

Gross pathology:

No specific gross pathological changes were recorded for any animal (for individual data see Table 5).

Other findings:

No abnormalities or treatment related effects have been observed.

Any other information on results incl. tables

Table 1:   LD50 Cut-Off

Dose (unit)	Number of Animals Investigated	Number of Intercurrent Deaths	LD50 Cut-Off
2000 mg/kg bw	6	0	unclassified

Table 2:  Results per Step

Step	Sex/No.	Dose (mg/kg)	Number of Animals	Number of Intercurrent Deaths
1	female (1 -3)	2000	3	0
2	female (4 -6)	2000	3	0

Table 3:  Clinical Signs - Individual Data

Animal No. / Sex	Time of Observation Post-Dose	Observations
Step 1 (2000 mg/kg Body Weight)
1 / female	during the whole observation period	no signs of toxicity
2 / female	during the whole observation period	no signs of toxicity
3 / female	during the whole observation period	no signs of toxicity
Step 2 (2000 mg/kg Body Weight)
4 / female	during the whole observation period	no signs of toxicity
5 / female	during the whole observation period	no signs of toxicity
6 / female	during the whole observation period	no signs of toxicity

Table 4:   Absolute Body Weights in g and Body Weight Gain in %

Animal No. / Sex	g Day 1	g Day 8	g Day 15	% Day 1-15
Step 1 (2000 mg/kg Body Weight)
1 / female	168	200	215	28
2 / female	148	167	177	20
3 / female	149	179	198	33
Step 2 (2000 mg/kg Body Weight)
4 / female	157	180	199	27
5 / female	151	175	182	21
6 / female	151	178	196	30

Table 5:   Findings of the Necropsy - Individual Data

Animal No./ Sex	Organ	Macroscopic Findings
Step 1 (2000 mg/kg Body Weight)
1 / female	-	nsf
2 / female	-	nsf
3 / female	-	nsf
Step 2 (2000 mg/kg Body Weight)
4 / female	-	nsf
5 / female	-	nsf
6 /female	-	nsf

nsf = no specific findings

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of the present study, a single oral application of the test item Graphite, acid treated to rats at a dose of 2000 mg/kg body weight was associated with no signs of toxicity or mortality.

The median lethal dose of Graphite, acid treated after a single oral administration to female rats, observed over a period of 14 days is:
LD50 cut-off (rat): unclassified

In conformity with the criteria given in Annex VI to Commission Directive 2001/59/EC the test item Graphite, acid treated has no obligatory labelling requirement for toxicity.
According to Annex I of Regulation (EC) 1272/2008 the test item Graphite, acid treated has no obligatory labelling requirement for toxicity and is unclassified.
According to OECD-GHS (Globally Harmonised Classification System) the test item Graphite, acid treated has no obligatory labelling requirement for toxicity.

Executive summary:

Two groups, each of three female WISTAR Crl: WI (Han) rats, were treated with the test item by oral gavage administration at a dosage of 2000 mg/kg body weight. The test item was suspended in the vehicle cottonseed oil at a concentration of 0.2 g/mL and administered at a dose volume of 10 mL/kg.

All animals used in the study after their entrance at BSL were allowed to acclimatise to the laboratory conditions for at least 5 days. The animals were observed on delivery, on inclusion in the study and before administration for mortality/morbidity and other clinical signs. All animals were examined for clinical signs several times on the day of dosing and once daily until the end of the observation period. Their body weights were recorded on day 1 (prior to the administration) and on days 8 and 15. All animals were necropsied and examined macroscopically.

Table1:  Results per Step

Step	Sex/No.	Dose (mg/kg)	Number of Animals	Number of Intercurrent Deaths
1	female/1-3	2000	3	0
2	female/4-6	2000	3	0

All animals survived until the end of the study without showing any signs of toxicity.

Throughout the 14-day observation period, the body weight gain of the test animals was within the normal range of variation for this strain.

At necropsy, no macroscopic findings were observed in any animal of any step.

On the basis of the test results given below and in conformity with the criteria given in Annex VI to Commission Directive 2001/59/EC[7]as well as in Annex I of Regulation (EC) 1272/2008[8], the substance should be not classified.