Registration Dossier

Administrative data

Endpoint:
developmental toxicity
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study

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:
OECD Guideline 414 (Prenatal Developmental Toxicity Study)
Deviations:
yes
Remarks:
- Soft-tissue examinations only on 1/3 instead of 1/2 of the foetuses. Post-treatment period of five days prior to caesarean sect.: Acc. to OECD TG 414 (22 Jan. 2001), dosage should cover the whole pregnancy up to 1 d prior to scheduled caesarean sect.
Qualifier:
according to
Guideline:
EPA OPP 83-3 (Prenatal Developmental Toxicity Study)
GLP compliance:
yes
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
US Type P1/13 based on GC/MS (Selection of Key Compounds)

- Substance type: organic
- Physical state: liquid

Distilled Coal Tar, Complex Hydrocarbon Mixture

Component CAS-No. [%][US P1/13]

Naphthalene 91-20-3 9.0
1-Methylnaphthalene 90-12-0 2.3
2-Methylnaphthalene 91-57-6 5.1
Indene 95-13-6 0.9
Fluorene 86-73-7 4.2
Acenaphthylene 208-96-8 0.3
Acenaphthene 83-32-9 6.1
Phenanthrene 85-01-8 12.2
Anthracene 120-12-7 2.2
Fluoranthene 206-44-0 6.8
Pyrene 129-00-0 6.0
Benz[a]anthracene 56-55-3 0.5
Chrysene 218-01-9 1.5
Benzo(a)pyrene 50-32-8 0.5

Total of 5 remaining EPA-PAH: ca. 1.4

(Benzo[b]fluoranthene, 205-99-2 0.8
Benzo[k]fluoranthene, 207-08-9 0.3
Indeno[1,2,3-cd]pyrene, 193-39-5 0.1
Dibenzo[a,h]anthracene, 53-70-3 not identified
Benzo[ghi]perylene, 191-24-2 <0.1

Test animals

Species:
rat
Strain:
other: SD, Crl:CD® VAF/Plus®
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories, Portage, Michigan, USA
- Age at study initiation: Approx. 13 weeks
- Weight at study initiation:210 – 278 g

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on exposure:
VEHICLE

- Concentration in vehicle: 2.5, 7.5, 22.5 mg/ml
- Amount of vehicle (if gavage):10 ml/(kg bw*d)
Analytical verification of doses or concentrations:
no
Details on mating procedure:
Mating period: Until detection of copulatory plug (= day 0 of gestation)
Duration of treatment / exposure:
Day 6-15 of gestation
Frequency of treatment:
1x/d
Duration of test:
Duration of exposure: Day 6-15 of gestation
Postexposure period: Day 16-20 of gestation.
Doses / concentrations
Remarks:
Doses / Concentrations:
25, 50, 175 mg/(kg bw*d)
Basis:
actual ingested
No. of animals per sex per dose:
30 mated females
Control animals:
yes, concurrent vehicle
Details on study design:
--

Examinations

Maternal examinations:
CAGE SIDE OBSERVATIONS: No data

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Daily on days 6-20

BODY WEIGHT: Yes
- Time schedule for examinations: Days 0, 6, 9, 12, 16 and 20

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes, days 0, 6, 9, 12, 16 and 20
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes / No / No data

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study) No


POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day 20


Ovaries and uterine content:
The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: Yes
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: Yes
- Number of late resorptions: Yes
- Other: Number and location of viable and non-viable fetuses
Fetal examinations:
- External examinations: Yes
- Soft tissue examinations: Yes
- Skeletal examinations: Yes
- Head examinations: No data

Litter size, number of dead foetuses, foetal weight, sex ratio, external alterations
Statistics:
--
Indices:
--
Historical control data:
--

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:
Maternal toxic effects:yes

Details on maternal toxic effects:
175 mg/(kg*d) dosage level: weak maternal toxicity as evidenced by increased hair loss, body weight loss during the first subinterval of treatment (gestation days 6-9), inhibition in body weight gain during the treatment period (days 6-16) and throughout gestation (until day 20), and decreased food consumption. There was a decreasing trend only without clear statistical significance.
50 mg/(kg*d) dosage level or lower: No evidence of maternal toxicity.

Effect levels (maternal animals)

open allclose all
Dose descriptor:
NOAEL
Effect level:
50 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
other: maternal toxicity
Dose descriptor:
LOAEL
Effect level:
175 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
other: maternal toxicity

Results (fetuses)

Details on embryotoxic / teratogenic effects:
Embryotoxic / teratogenic effects:yes

Details on embryotoxic / teratogenic effects:
Developmental toxicity at the 175 mg/(kg*d) dosage level: Increased incidence in post-implantation loss (including three whole litter resorptions vs. one litter resorbed in the vehicle control and none in the other treated groups), and reduced number of live foetuses. No adverse effect was demonstrated for late intrauterine development of live foetuses at any dose.
No evidence of developmental toxicity was observed at the 50 mg/(kg*d) dosage level or lower.
One, six, seven, and seven foetuses showed malformations in one, three, six, and five litters for the control, low-, mid-, and high-dose groups, respectively. The incidences for the mid-, and high-dose levels were significantly higher than for the control group. Most of the observed malformations are fairly common in rats and the values obtained for the eye malformations in this study were within historical control range. After factoring out these common eye abnormalities, each type of the remaining malformations occurred in only one or two instances per group. Thus, the malformations were not considered to be test-article related.
Developmental variations that occurred did not follow a dose-related pattern.

Effect levels (fetuses)

open allclose all
Dose descriptor:
NOAEL
Effect level:
50 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
other: embryotoxicity
Dose descriptor:
LOAEL
Effect level:
175 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
other: embryotoxicity
Dose descriptor:
NOAEL
Effect level:
175 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
other: fetotoxicity
Dose descriptor:
LOAEL
Effect level:
> 175 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
other: fetotoxicity
Dose descriptor:
NOAEL
Effect level:
175 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
other: teratogenicity
Dose descriptor:
LOAEL
Effect level:
> 175 mg/kg bw/day (nominal)
Based on:
test mat.
Basis for effect level:
other: teratogenicity

Fetal abnormalities

Abnormalities:
not specified

Overall developmental toxicity

Developmental effects observed:
not specified

Any other information on results incl. tables

 Table forMaternal Effects

Parameter

Control data

25  

mg/(kg*d)

50

mg/(kg*d)

175

mg/(kg*d)

Dose-response
+ / –

historical

study

Number of dams examined

716

30

30

30

30

Pregnant females

27

20

23

23

Pregnancies [%]

90.0

66.0

76.0

76.0

Clinical findings during application of test substance

13

15

11

17

Mortality of dams [%]

0

0

0

0

0

Body weight gain

day 0-6

34

34

32

30

day 6-9

2

5

3

-2

day 9-12

12

12

13

12

day 12-16

28

21

25

21

day 16-20

57

65

64

51

day 6-16

42

38

40

31

day 0-20

143

133

137

136

112

Final dam weight change minus weight of uterus

62

64

67

66

61

Food consumption [g/animal/day]

day 0-6

21.2

21.0

20.2

20.5

day 6-9

14.6

16.7

14.4

12.9

day 9-12

14.1

15.5

14.1

13.6

day 12-16

17.9

15.0

12.6*

9.8**

+

day 16-20

25.5

28.6

29.5

30.4

day 6-16

15.7

15.7

13.6

11.9**

+

day 0-20

19.4

19.9

18.8

18.2

Necropsy findings in dams dead before end of test

No deaths occurred before end of test.

* Significantly different from controls, p ≤ 0.05
** Significantly different from controls, p ≤ 0.01

Table forDevelopmentalEffects

Litter response (Caesarean section data)

Parameter

Controldata

25 mg/kg/ day

50 mg/kg/ day

175 mg/kg/ day

Dose-response
+ / -

historical

study

Corpora lutea

mean/dam

16.8

16.6

16.0

16.3

16.0

Implantations

mean/dam

15.0

14.2

13.8

14.6

12.9

Resorptions

total/number of dams

850/708

31/27

17/20*

25/23

59/23*

+

Number of foetuses/dam

13.0

13.0

13.5

10.3

Pre-implantation loss [%]

11.6

13.8

10.6

12.2

Post-implantation loss [%]

7.3

8.1

6.2

7.4

19.9

+

Total number of litters

26

20

23

20

Foetuses / litter

13.0

13.0

13.5

10.3

Live foetuses / litter

ratio

13.9

13.0

13.0

13.5

10.3

Dead foetuses / litter ratio

0

0

0

0

Foetus weight (mean) [g]

3.4

3.3

3.5

3.3

3.2

Male foetuses

3.4

3.6

3.4

3.3*1)

+

Female foetuses

3.3

3.3

3.2

3.2

Uterine weight (mean) [g]

76.3

72.0

69.5

70.0

61.4

Crown-rump length (mean)[mm]

35

36

35

35

Foetal sex ratio [state ratio m/f]

0.982

1.108

0.904

1.006

1.135

* Significantly different from controls, p ≤ 0.05

1)questionable, no effect on crown length, see also female values, considered biologically irrelevant

   Table forMorphologicalEffects

Examination of the foetuses(Report, Tab. 9 + 10, p. 42/43)

Parameter

Controldata

25 mg/kg/ day

50 mg/kg/ day

175 mg/kg/ day

Dose-response
+ / -

historical

study

External malformations*[%]

0.20

0.00

0.77

2.891)

1.27

Skeletal malformations*[%]

0.93

0.00

0.81

4.351)

1.72

Visceral malformations*[%]

0.41

0.58

2.21

1.33

2.50

Fetuses with malformations [%]*

0.58

3.8

3.92)

5.5

External variations*[%]

0.01

0.00

0.00

0.00

0.00

Skeletal variations*[%]

34.4

36.7

50.4

49.7

43.1

Visceral variations*[%]

1.44

10.5

11.0

7.33

1.67

*Figures are not given in the original study but calculated from the number of observations and the number of examined foetuses in the respective category.

1)The relatively high incidences are only determined by an accumulation of 11 different skeletal and external malformations within one foetus from doe No. 56513 (Report, Appendix C, p. 100).

2)Because of multi-fold malformations observed in two foetuses (one with 4 and a second with 2 defects), the percentage of the number of animals with malformations is lower than the total percentage of malformations (comp. Report,Appendix C, p. 98ff). Four other foetuses carried only one structural defect as in the other dose groups.

Applicant's summary and conclusion