Petroleum heavy cycle oil, co-processed (catalytic cracking) with renewable hydrocarbons of plant or animal origin

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / bone marrow chromosome aberration

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Near-guideline, GLP-compliant study. Adequate for assessment.

Justification for type of information:

Read across justification included in Section 13

Cross-reference

Reason / purpose for cross-reference:

read-across: supporting information

Reference

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / bone marrow chromosome aberration

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Near-guideline, GLP-compliant study. Adequate for assessment.

Justification for type of information:

Read across justification included in Section 13

Reason / purpose for cross-reference:

read-across source

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 475 (Mammalian Bone Marrow Chromosome Aberration Test)

Principles of method if other than guideline:

The frequency of chromosomal aberrations in rat bone marrow was determined following 5 consecutive daily treatments via oral gavage.

GLP compliance:

yes

Type of assay:

chromosome aberration assay

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories
- Group housed: 4/sex/cage
- Diet (Purina Laboratory Chow) and tap water available ad libitum
- No further details

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

5 consecutive daily exposures, 24 hr apart, administered by oral gavage in corn oil

Duration of treatment / exposure:

5 days

Frequency of treatment:

Daily

Post exposure period:

Animals sacrificed 6 hr after last treatment

Remarks:

Doses / Concentrations:
0.1, 0.3 and 1.0 g/Kg bw/d
Basis:
other: nominal in vehicle

No. of animals per sex per dose:

0.1 g/Kg/d, 0.3 g/Kg/d, positive controls, vehicle controls: 10 males and 10 females per treatment
1 g/Kg/d: 13 males and 13 females per treatment

Control animals:

yes, concurrent vehicle

Positive control(s):

triethylenemelamine, 1 mg/Kg bw, administered as single i.p. injection

Tissues and cell types examined:

Tibial bone marrow cells

Details of tissue and slide preparation:

CRITERIA FOR DOSE SELECTION:
Based on results of preliminary dose range findings investigation (survival following 5 consecutive daily gavage treatments of 0, 0.5, 1.5 or 3.0 g/kg bwt)

DETAILS OF SLIDE PREPARATION:
Tibial bone marrow cells washed, isolated (centrifugation) and fixed (methanol:acetic acid); air-dried spreads stained with 5% Giemsa (pH 6.8)

METHOD OF ANALYSIS:
Slides were coded and scored blind. 50 spreads per animal were subject to microscopic examination and scored for gaps, breaks, fragments and reunion figures. At least 500 cells per spread were evaluated.

Evaluation criteria:

Potential aberrations included: chromatid gap or break; chromosome gap or break; chromatid deletion; fragment or acentric fragment; transolcation; triradial; quadriradial; pulverised chromsome or cells; complex rearrangement; ring chromosome; dicentric chromosome; minute chromsome; greater than 10 aberrations; polyploid; hyperploid

Statistics:

Students T-test

Sex:

male/female

Genotoxicity:

negative

Toxicity:

yes

Remarks:

40-60% mortality at 1.5 g/Kg bw; 30-100% mortality at 3 g/Kg bw

Vehicle controls validity:

valid

Negative controls validity:

not examined

Positive controls validity:

valid

The test substance did not significantly increase the frequency of chromosomal aberrations, nor did it increase the mitotic index in male and female bone marrow cells at any dose.

The positive control group animals produced significant increases in chromosomal aberration frequencies.

 

Condition	Aberrations per cell		Percent cells with structural aberrations		Mitotic index %
	Structural	Numerical	1 or more	2 or more
Negative control (corn oil)	0.002 (m) 0.007 (f)	0.006 (m) 0.002 (f)	0.6 (m) 0.2 (f)	0 (m) 0 (f)	5.5 (m) 4.5 (f)
Positive control (TEM)	0.00	>4.8 (m) >2.5 (f)	69.7 (m) 43.9 (f)	62.6 (m) 32.8 (f)	0.8 (m) 1.0 (f)
0.1 g/Kg bw	0.002 (m) 0.007 (f)	0.006 (m) 0.016 (f)	0.2 (m) 0.7 (f)	0 (m) 0 (f)	5.4 (m) 4.1 (f)
0.3 g/Kg bw	0.004 (m) 0.008 (f)	0.014 (m) 0.008 (f)	0.4 (m) 0.8 (f)	0 (m) 0 (f)	5.0 (m) 4.0 (f)
1.0 g/Kg bw	0.004 (m) 0.010 (f)	0.002 (m) 0.004 (f)	0.4 (m) 1.0 (f)	0 (m) 0 (f)	6.0 (m) 3.3 (f)

Conclusions:

Interpretation of results (migrated information): negative
Not clastogenic to bone marrow in vivo.

Executive summary:

The clastogenic potential of catalytic cracked clarified oil towards rat bone marrow cells was invested in vivo in a near-guideline GLP-compliant investigation. Animals received 5 consecutive daily gavage treatments of 0 (corn oil), 0.1, 0.3 or 1.0 g/Kg bw/d prior to sacrifice, while positive controls were given a single i.p. injection of 0 or 1 mg/Kg triethylenemelamine. At least 500 cells from 50 Giemsa stained spreads per animal were examined microscopically and scored blind for the presence of structural and numerical aberrations.

There was no treatment-related alteration in chromosomal aberrations however a satisfactory response was obtained in the positive control group. The test substance was not clastogenic in this in vivo test.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 475 (Mammalian Bone Marrow Chromosome Aberration Test)

Principles of method if other than guideline:

The frequency of chromosomal aberrations in rat bone marrow was determined following 5 consecutive daily treatments via oral gavage.

GLP compliance:

yes

Type of assay:

chromosome aberration assay

Test material

Test material information

Constituent 1

Reference substance name:

64741-62-4

Cas Number:

64741-62-4

IUPAC Name:

64741-62-4

Test material form:

other: Viscous hydrocarbon liquid

Details on test material:

Catalytic cracked clarified oil (CCCO), API 81-15, CAS No. 64741-62-4.
Dark brown viscous liquid

Data below taken from American Petroleum Institute (1985d). In-vivo sister chromatid exchange (SCE) assay. Catalytic cracked clarified oil, API Sample 81-15, CAS No. 64741-62-4. Testing laboratory: Microbiological Associates Inc., 5221 River Road, Bethesda, MD 20816, USA. Owner company: American Petroleum Institute, 2101 L Street, Northwest, Washington, DC 20037, USA. Study number: 32-32754. Report date: 1985-11-25.

Gravity API: 0.1
Specific gravity: 1.0753
Viscosity in SUS @ 210 °F: 56.1
Flash Point °F: 396
Sulfur wt %: 1.1
Pour Pt °F: 35
Asphaltenes % (MN 596): 4.2
Carbon residue wt %: 4.6
Ash wt %: 0.05

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 Breeding Laboratories
- Group housed: 4/sex/cage
- Diet (Purina Laboratory Chow) and tap water available ad libitum
- No further details

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

5 consecutive daily exposures, 24 hr apart, administered by oral gavage in corn oil

Duration of treatment / exposure:

5 days

Frequency of treatment:

Daily

Post exposure period:

Animals sacrificed 6 hr after last treatment

Doses / concentrations

Remarks:

Doses / Concentrations:
0.1, 0.3 and 1.0 g/Kg bw/d
Basis:
other: nominal in vehicle

No. of animals per sex per dose:

0.1 g/Kg/d, 0.3 g/Kg/d, positive controls, vehicle controls: 10 males and 10 females per treatment
1 g/Kg/d: 13 males and 13 females per treatment

Control animals:

yes, concurrent vehicle

Positive control(s):

triethylenemelamine, 1 mg/Kg bw, administered as single i.p. injection

Examinations

Tissues and cell types examined:

Tibial bone marrow cells

Details of tissue and slide preparation:

CRITERIA FOR DOSE SELECTION:
Based on results of preliminary dose range findings investigation (survival following 5 consecutive daily gavage treatments of 0, 0.5, 1.5 or 3.0 g/kg bwt)

DETAILS OF SLIDE PREPARATION:
Tibial bone marrow cells washed, isolated (centrifugation) and fixed (methanol:acetic acid); air-dried spreads stained with 5% Giemsa (pH 6.8)

METHOD OF ANALYSIS:
Slides were coded and scored blind. 50 spreads per animal were subject to microscopic examination and scored for gaps, breaks, fragments and reunion figures. At least 500 cells per spread were evaluated.

Evaluation criteria:

Potential aberrations included: chromatid gap or break; chromosome gap or break; chromatid deletion; fragment or acentric fragment; transolcation; triradial; quadriradial; pulverised chromsome or cells; complex rearrangement; ring chromosome; dicentric chromosome; minute chromsome; greater than 10 aberrations; polyploid; hyperploid

Statistics:

Students T-test

Results and discussion

Test results

Sex:

male/female

Genotoxicity:

negative

Toxicity:

yes

Remarks:

40-60% mortality at 1.5 g/Kg bw; 30-100% mortality at 3 g/Kg bw

Vehicle controls validity:

valid

Negative controls validity:

not examined

Positive controls validity:

valid

Any other information on results incl. tables

The test substance did not significantly increase the frequency of chromosomal aberrations, nor did it increase the mitotic index in male and female bone marrow cells at any dose.

The positive control group animals produced significant increases in chromosomal aberration frequencies.

 

Condition	Aberrations per cell		Percent cells with structural aberrations		Mitotic index %
	Structural	Numerical	1 or more	2 or more
Negative control (corn oil)	0.002 (m) 0.007 (f)	0.006 (m) 0.002 (f)	0.6 (m) 0.2 (f)	0 (m) 0 (f)	5.5 (m) 4.5 (f)
Positive control (TEM)	0.00	>4.8 (m) >2.5 (f)	69.7 (m) 43.9 (f)	62.6 (m) 32.8 (f)	0.8 (m) 1.0 (f)
0.1 g/Kg bw	0.002 (m) 0.007 (f)	0.006 (m) 0.016 (f)	0.2 (m) 0.7 (f)	0 (m) 0 (f)	5.4 (m) 4.1 (f)
0.3 g/Kg bw	0.004 (m) 0.008 (f)	0.014 (m) 0.008 (f)	0.4 (m) 0.8 (f)	0 (m) 0 (f)	5.0 (m) 4.0 (f)
1.0 g/Kg bw	0.004 (m) 0.010 (f)	0.002 (m) 0.004 (f)	0.4 (m) 1.0 (f)	0 (m) 0 (f)	6.0 (m) 3.3 (f)

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative
Not clastogenic to bone marrow in vivo.

Executive summary:

The clastogenic potential of catalytic cracked clarified oil towards rat bone marrow cells was invested in vivo in a near-guideline GLP-compliant investigation. Animals received 5 consecutive daily gavage treatments of 0 (corn oil), 0.1, 0.3 or 1.0 g/Kg bw/d prior to sacrifice, while positive controls were given a single i.p. injection of 0 or 1 mg/Kg triethylenemelamine. At least 500 cells from 50 Giemsa stained spreads per animal were examined microscopically and scored blind for the presence of structural and numerical aberrations.

There was no treatment-related alteration in chromosomal aberrations however a satisfactory response was obtained in the positive control group. The test substance was not clastogenic in this in vivo test.