[4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium acetate

Toxicity to reproduction

Administrative data

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

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

Adequacy of study:

key study

Study period:

1983

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No GLP, no guidelines followed, poorly details on test conditions Read across from a similar substance which has the same main component and with a different counter ion that doesn't influence the characteristics related to the specific end-point

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1983

Report date:

1983

Materials and methods

Principles of method if other than guideline:

Malachite Green was administrated to Rabbits by oral gavage. Thalidomide was used as positive
control and untreated animals as untreated control.

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Malachite Green Oxalate

IUPAC Name:

Malachite Green Oxalate

Details on test material:

- Name of test material: Malachite Green Oxalate
- Source: Dansk Orredforder A/S, Brande, Danmark
- Structure: (C23H25N)2 (COO)2 X 2 (COOH)2
- Analytical purity: > 90% detected by TLC

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

female

Details on test animals or test system and environmental conditions:

ANIMALS TESTED
- Specie: Oryctolagus cuniculus
- Source: commercial laboratory supplier Scott Rabbit Products, Langley, Washington
- Age at study initiation: time-pregnant
- Housing: all animals were housed individually
- Diet: Purina Laboratory Rabbit Chow supplemented by fresh greens
- Water: water ad libitum
CONTROL
- Group: two control group were used: one untreated and one like positive control (treated by
Thalidomide, a known teratogen)

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

DIET
- Dose: 5, 10, 20 mg/kg
- Solution: Malachite Green was administrated as an aqueous solution.
- Administration: orally by gavage on days 6 through 18 of gestation
- N. initial animals: 20
POSITIVE CONTROL SOLUTION
- Solution: thalidomide was used as a positive control
- Preparation: Thalidomide was prepared as a suspension in corn oil
- Dose: 150 mg/kg

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

18 days of gestation; orally administration by gavage on days 6 through 18 of gestation

Frequency of treatment:

Frequency of treatment
Daily

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

5 mg/kg diet

Doses / concentrations 2

Dose / conc.:

10 mg/kg diet

Doses / concentrations 3

Dose / conc.:

20 mg/kg diet

No. of animals per sex per dose:

At dose 5 mg/kg 16 animals; at 10 mg/kg 21; at 20 mg/kg 16.

Control animals:

yes, concurrent vehicle

Details on study design:

PRELIMINARY TEST
Consequently, doses of 2, 50, and 75 mg/kg were selected to determine the maximum dose to be
used with rabbits. Three young, nonpregnant adult New Zealand white rabbits were dosed daily for
13 days in each treatment. Data from this limited study indicated that nonpregnant female rabbits co
uld tolerate 13 consecutive daily doses of 50 mg/kg of Malachite Green. Stanford Research Institute
experience has been that pregnant rabbits are much more sensitive to drugs than nonpregnant ones
so 20 mg/kg was selected as the maximum level to be used in the teratology study.

Examinations

Parental animals: Observations and examinations:

PRELIMINARY TEST
Consequently, doses of 2, 50, and 75 mg/kg were selected to determine the maximum dose to be
used with rabbits. Three young, nonpregnant adult New Zealand white rabbits were dosed daily for
13 days in each treatment. Data from this limited study indicated that nonpregnant female rabbits co
uld tolerate 13 consecutive daily doses of 50 mg/kg of Malachite Green. Stanford Research Institute
experience has been that pregnant rabbits are much more sensitive to drugs than nonpregnant ones
so 20 mg/kg was selected as the maximum level to be used in the teratology study.
OTHER:
Young were thoroughly examined at delivery, weighed and incubated for 24 hours. During incubation
they were observed hourly for viability during the first 4 hours and again at 24 hours

Litter observations:

yes

Postmortem examinations (parental animals):

yes

Postmortem examinations (offspring):

yes

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

Treated adult animals were consistently lower in average total body weight than the untreated controls
at the end of the study, but there were no overt signs of toxicity

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Effect levels (P0)

Dose descriptor:

NOEL

Effect level:

< 5 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

female

Basis for effect level:

clinical signs

body weight and weight gain

reproductive performance

Results: F1 generation

Effect levels (F1)

Dose descriptor:

NOEL

Generation:

F1

Effect level:

< 5 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

not specified

Basis for effect level:

viability

clinical signs

other: scheletal malformations

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

At all

three doses there were significant increases in preimplantation losses, primarily due to early resorption of fetuses

and decreases in the number of living fetuses.

Applicant's summary and conclusion

Conclusions:

At all
three doses there were significant increases in preimplantation losses, primarily due to early resorption of fetuses
and decreases in the number of living fetuses.