Reaction mass of 1,3-dioxan-5-ol and 1,3-dioxolan-4-ylmethanol

Toxicity to reproduction

Administrative data

Endpoint:

reproductive toxicity, other

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

From 01 December 1981 to 28 July 1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Principles of method if other than guideline:

- Principle of test: Females treated prior to mating, during mating and gestation until PND 20
- Short description of test conditions: Females are exposed to Glycerol formal for 14 days prior to mating, during mating and gestation. Males used during mating are not treated. Females are treated up to PND 20. Pups are then used for a 90-day oral toxicity study
- Parameters analysed / observed: clinical signs, bodyweight, number of metrial glands in dams, litter observations

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Glycerol formal

IUPAC Name:

Glycerol formal

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River France, 76410 Saint Aubin les Elbeuf, France
- Age at study initiation: (P) 16 wks
- Weight at study initiation: (P) Females: 214-247 g
- Fasting period before study: not specified
- Housing: Cages in an air-controlled room
- Diet: ad libitum; certified UAR"A 04"
- Water: ad libitum; tap water
- Acclimation period: not specified
ENVIRONMENTAL CONDITIONS
- Temperature (°C): not specified
- Humidity (%): not specified
- Air changes (per hr): not specified
- Photoperiod (hrs dark / hrs light): 12 hours dark/12 hours light
IN-LIFE DATES: From: 01 December 1981 To: 26 January - 03 February 1982

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: Solutions prepared daily, stability and concentration confirmed by chemical analysis

VEHICLE
- Amount of vehicle (if gavage): 5 ml/kg bw of solution (females)

Details on mating procedure:

- M/F ratio per cage: 1M/2F
- Length of cohabitation: females were sacrificed if they did not mate within an 8-day period.
- Proof of pregnancy: detection of spermatozoa in the daily vaginal lavage referred to as day 0 of pregnancy
- After successful mating each pregnant female was caged individually

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Concentration confirmed by chemcial analysis

Duration of treatment / exposure:

(P) males untreated
(P) females treated 14 days prior to mating, during mating and gestation until PND 20 of pups

Frequency of treatment:

Once daily

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

25 mg/kg bw/day (nominal)

Doses / concentrations 2

Dose / conc.:

5 mg/kg bw/day (nominal)

Doses / concentrations 3

Dose / conc.:

1 mg/kg bw/day (nominal)

Doses / concentrations 4

Dose / conc.:

0 mg/kg bw/day (nominal)

No. of animals per sex per dose:

20 females
10 untreated males

Control animals:

yes, concurrent vehicle

Examinations

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily but with less extensive examinations on week-end and holidays

BODY WEIGHT: Yes
- Time schedule for examinations: on days -15, -8, and -1 of prebreeding period, on days 1, 6, 14, 16, 18, 20 and 21 of gestation and on days 2, 7, 14 and 21 during lactation

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: yes
- If yes, maximum of 8 pups/litter (4/sex/litter as nearly as possible); excess pups were killed and discarded.

PARAMETERS EXAMINED
The following parameters were examined in F1 offspring: on day 1 postpartum, pups counted, examined externally and sexed. Pups examined daily and sexed again on days 14 and 21. At the end of the study, 3 to 4-week old pups were selected for continuation on a three-month oral toxicity study and male fertility study of Glycerol formal. Pups are examined daily and weighed on days 1, 7, 14 and 21 postpartum.

Statistics:

Statistical analyses of the following parameters: female body weight changes during pre-breeding, gestation, and lactation; time to mating; verified matings/number of females; number of pregnancies per number of verified matings; postimplantation survival rate; gestation length; number of dead pups per litter; average live pup weight per litter days 1, 7, 14, 21; and average number of dead pups on day 1, days 7 to 14, 14 to 21, and 1 to 21. The computer examined the data for normality using the Wilk and Shapiro statistic and for homogeneity of variances using the Levene test. Statistical significance at p = 0.05 based on an analysis of variances after normalizing for nonparametric data when necessary. In addition, effects of the number of live pups per litter and the average length of gestation on the average live Day 1 pup weight were analyzed by single covariance analysis and the data adjusted prior to further statistical manipulation.

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

Average body weight gain was slightly but significantly lower in females from the 25 mg/kg/day group compared to the control group during the Days -15 to -1 of the prebreeding period. The average body weight gain was significantly increased relative to the controls in this group on days 6 to 14 and 1 to 20 of gestation. Since these differences in mean weight gain between control and drug treated groups were very slight, and not consistent during the prebreeding and gestation and lactation periods, they were not considered treatment-related.
Table 1

Reproductive function / performance (P0)

Reproductive performance:

no effects observed

Description (incidence and severity):

There were no treatment-related effects on reproductive status, mating performance, length of gestation or post implantation survival rate of F0 females. Tables 2 and 3

Effect levels (P0)

Key result

Dose descriptor:

NOAEL

Effect level:

25 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

female

Basis for effect level:

clinical signs

mortality

body weight and weight gain

reproductive performance

Target system / organ toxicity (P0)

Key result

Critical effects observed:

no

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

mortality observed, non-treatment-related

Description (incidence and severity):

The number of dead pups from day 8 to day 14 postpartum was significantly higher in rats from the 1 mg/kg/day group than in other groups. There was no increase in mortality in this group on day 1 or day 21 postpartum and no treatment-related increase in dead pups was seen in the 5 or 25 mg/kg/day groups throughout the lactation period.

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

Average live pup weight per litter was significantly higher in pups from the 1 mg/kg/day group on day 21 and in pups from the 25 mg/kg/day group on days 7 and 21 post partum compared to the control group. However, there were no significant differences (p> 0.05) in average pup weight in the 5 mg/kg/day group during the lactation period. In view of the magnitude of the differences in body weight in pups from the low and high dosage level groups and the lack of an apparent dose-response, these changes were considered as incidental.

Effect levels (F1)

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

25 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

clinical signs

mortality

body weight and weight gain

Target system / organ toxicity (F1)

Key result

Critical effects observed:

no

Overall reproductive toxicity

Key result

Reproductive effects observed:

no

Any other information on results incl. tables

Table 1: Average female body weight (grams)

	Control	Glycerol formal (mg/kg/day)
		1	5	25
Average body weight (g) during prebreeding
Day -15	238	240	236	241
Day -8	248	250	248	247
Day -1	255	258	254	255
Change
Days -15 to -8	10	10	10	6*
Days -8 to -1	7	8	6	8
Days -15 to -1	17	18	18	14*
Average body weight (g) during gestation
Day 1	265	272	267	269
Day 6	286	298	290	291
Day 14	324	340	331	335
Day 16	342	358	348	354
Day 18	368	386	374	384
Day 20	397	415	401	414
Change
Days 1 to 6	21	26*	23	22
Days 6 to 14	38	42	41	44*
Days 14 to 20	73	75	70	79
Days 1 to 20	132	143*	134	145*
Average body weight (g) during lactation
Day 2	310	327	320	317
Day 7	325	336	334	332
Day 14	347	356	351	353
Day 21	342	350	350	346
Change
Days 2 to 21	32	23	30	29

* = statistically significantly different from controls

Table 2: Reproductive status table (dams)

	Control	1 mg/kg/day	5 mg/kg/day	25 mg/kg/day
Total number of females	20	20	20	20
Live pregnant	16	18	16	17
Live not pregnant	2	1	1	0
Died pregnant	0	0	0	0
Died not pregnant	0	0	0	0
Sacrificed pregnant	0	0	1	0
Sacrificed not pregnant	0	0	0	0
Aborted	0	0	0	0
Died incomplete parturition	0	0	0	0
Sacrificed incomplete parturition	0	0	1	0
Died postpartum	0	0	0	0
Sacrificed postpartum	0	0	0	0
Not bred	2	1	1	3
Sacrificed	0	0	0	0
Died	0	0	0	0
Total number of identified matings/total number of females	18/20	19/20	19/20	17/20
Days 1 to 4 of breeding	17	18	18	14
Days 5 to 8 of breeding	1	1	1	3
Days 9 to 12 of breeding	0	0	0	0
Pregnancies/verified matings	16/18	18/19	18/19	17/17
Time to mating	1.0556	1.0526	1.0526	1.1765
Average length of gestation (hours)	13.3	18.2	17.7	16.9
Post implantation survival rate (%)	93.54	91.99	90.08	91.15

 

Table 3: Reproductive status table (pups)

	Control	1 mg/kg/day	5 mg/kg/day	25 mg/kg/day
Number of litters	16	18	16	17
Day 1 postpartum
Total no. of pups	216	239	203	243
Sex males/females (unknown)	85/131	124/115	108/95	123/118 (2)
No. live	214	237	202	239
No. live after reduction	128	144	123	136
No. dead	2	2	1	4
No. dead pups per litter	0.125	0.111	0.062	0.235
No. live per litter	13.4	13.2	12.6	14.0
No. live pup weight (g)/litter	6.07	6.40	6.28	6.43
Day 7 postpartum
No. live	123	136	121	135
No. dead pups days 2 to 7 (days 1 to 7)	5 (7)	8 (10)	2 (3)	1 (5)
Average live pup weight (g)/litter	11.90	12.70	12.71	13.06*
Day 14 postpartum
No. live	123	133	121	135
No. dead pups days 8 to 14 (days 8 to 14)	0 (7)	3* (13)	0 (3)	0 (5)
Average live pup weight (g)/litter (a)	25.25	27.15	26.14	26.98
Day 21 postpartum
No. live	123	133	121	134
No. dead pups days 15 to 21 (days 1 to 21)	0 (7)	0 (13)	0 (3)	1 (6)
Average live pup weight (g)/litter (a)	40.05	43.35*	41.79	43.47*

(a): statistical significance at p = 0.05 after adjustment for length of gestation

*: statistically significant different from control

Applicant's summary and conclusion

Conclusions:

No clinical signs were observed in females and no treatment-related effects were reported on reproductive status, mating performance, length of gestation, or postimplantation survival rate

Executive summary:

During this oral reproduction study, females rats were exposed to Glycerol formal for 14 days prior to mating (with unexposed males), during mating and gestation until PND 20 of pups. Female rats were treated by gavage with Glycerol formal at doses of 0, 1, 5 or 25 mg/kg/day. However, males were untreated.

Observations made include body weight, number of metrial glands, litter and reproductive parameters.

No treatment-related observations were noted.