2,4,7,9-tetramethyldec-5-yne-4,7-diol

Toxicity to reproduction

Administrative data

Endpoint:

one-generation reproductive toxicity

Remarks:

other: one generation reproduction study preceeds OECD Guidelines

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1979

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:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 415 [One-Generation Reproduction Toxicity Study (before 9 October 2017)]

Deviations:

not applicable

Principles of method if other than guideline:

Design of Study I Single Generation Reproduction Study in the Rat (F0->F1a):
Design of study II Ninety One Day Feeding Study (F1a Rats):

Ten male and twenty female sexually mature rats per groups were exposed to the following levels of 2,4,7,9-Tetramethyl-5-decyne-4,7-diol:

1. Low Dose: 500 mg/kg/d
2. Mid Dose: 1,000 mg/kg/d
3. High Dose: 2,000 mg/kg/d

The animals were mated and the newborn raised to weanling age.
The weanlings were randomized to their respective groups according to SOPs and carried on the same levels to the termination of the experiment.
Body weight and feed consumption data as well as several reproductive parameters were taken from the Fo rats.
Body weight and consumption data were taken weekly from the F1a rats.
Certain hematological and urine analytical parameters were performed on five male and five female F1a rats per group after 45 days and after 91 days.
Certain clinical chemistry parameters were performed on five male and five female rats per group after 91 days on test.
Gross necropsy was performed on all rats.
Organ weights and organ-to-body weight ratios were done on ten male and ten female F1a rats per group.
Complete histopathology was done on ten male and ten female rats from the high dose and control group while the major organs were examined histopathologically from all remaining survivors.

GLP compliance:

no

Remarks:

study performed before implementation of GLP

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2,4,7,9-tetramethyldec-5-yne-4,7-diol

EC Number:

204-809-1

EC Name:

2,4,7,9-tetramethyldec-5-yne-4,7-diol

Cas Number:

126-86-3

Molecular formula:

C14 H26 O2

IUPAC Name:

2,4,7,9-tetramethyldec-5-yne-4,7-diol

Details on test material:

Lot Number: 2910-109
Purity: 100 %

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, Wilmington, Mass.
- Acclimation period: four weeks
- Housing: The animals were housed individually during quarantine in steel wire mesh suspended cages in a room by themselves with a constant temperature of 73° +/- 3° F (equal to 23° +/- 2° C), with a constant humidity of approximately 40 % to 70 % and with 100 % fresh air make-up, approximately eight to ten complete air changes per hour.
- Diet, Water: Feed and water were provided ad libitum.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 23° +/- 2° C
- Humidity (%): 40 % to 70 %
- Air changes (per hr): 8 - 10

Administration / exposure

Route of administration:

oral: feed

Vehicle:

other: diet: Charles River 19RF, Rat, Mouse, Hamster Meal

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:

DIET PREPARATION

- Rate of preparation of diet (frequency):
The test diets were prepared weekly by the respective study coordinator, based on the mean body weight and the mean feed consumption during the second previous week.

- Mixing appropriate amounts with (Type of food):
The basic feed supply for the duration of the experiment was "Charles River 19RF, Rat, Mouse, Hamster Meal" manufactured by Agway of syracuse, New York. Test diets were prepared weekly by mixing the appropriate amount of 2,4,7,9-Tetramethyl-5-decyne-4,7-diol with the appropriate amount of basic diet in a three cubic feet Patterson Kelley twin shell mixer, tumbling at a rate of 40 tumples per minute around a high speed coaxial mixing bar equipped with discs bearing slanted blades rotating at the rate of 2,000 rpm. Fresh diets were prepared weekly. Feed consumption was measured by weighing the feed containers full of feed at the beginning of the week (full weight) and the same feed containers with the remaining feed at the end of the week (empty weight). All feed remaining at the end of the week was disposed of.

Details on mating procedure:

- M/F ratio per cage: individual housing

Analytical verification of doses or concentrations:

not specified

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

500 mg/kg bw/day (nominal)

Remarks:

Basis:
nominal in diet

Doses / concentrations 2

Dose / conc.:

1 000 mg/kg bw/day (nominal)

Remarks:

Basis:
nominal in diet

Doses / concentrations 3

Dose / conc.:

2 000 mg/kg bw/day (nominal)

Remarks:

Basis:
nominal in diet

No. of animals per sex per dose:

10 male
20 female

Control animals:

yes

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Description (incidence and severity):

No rats expired in this phase of the experiment.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Only one pertinent finding: The mean body weight of the high dose female group after weaning its young was significantly lower than the corresponding control.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Only one pertinent finding: The mean body weight of the high dose female group after weaning its young was significantly lower than the corresponding control.

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Description (incidence and severity):

Histopathology examination of the reproductive organs from all Fo parents revealed no abnormalities.

Other effects:

effects observed, treatment-related

Description (incidence and severity):

Test substance intake: The feed consumption of the high dose female group after weaning its young was significantly lower than the control. There was no other pertinent findings.

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Details on results (P0)

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS): All rats survived for the duration of the study.

BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS): Only one pertinent finding: The mean body weight of the high dose female group after weaning its young was significantly lower than the corresponding control.

TEST SUBSTANCE INTAKE (PARENTAL ANIMALS): The feed consumption of the high dose female group after weaning its young was significantly lower than the control. There was no other pertinent findings.


GROSS PATHOLOGY (PARENTAL ANIMALS): No gross abnormalities were observed in any of the Fo parents, either male or female.

HISTOPATHOLOGY (PARENTAL ANIMALS): Histopathology examination of the reproductive organs from all Fo parents revealed no abnormalities.

OTHER FINDINGS (PARENTAL ANIMALS): None

Effect levels (P0)

Dose descriptor:

NOAEL

Effect level:

500 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

Target system / organ toxicity (P0)

Critical effects observed:

no

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Description (incidence and severity):

No abnormal clinical sign were observed in any of the rats, either test or control, during the entire study period.

Mortality / viability:

no mortality observed

Description (incidence and severity):

No rats expired in this phase of the experiment.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

There was persistent statistically significant decrease in the rate of mean weekly body weight gain in the high dose rats, goth male and female, througout the experiment, for most weeks in the mid dose rats, both male and female, and for ...

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

Increase of liver weight

Gross pathological findings:

no effects observed

Description (incidence and severity):

No pertinent gross pathology findings were observed in any of the F1a rats at terminal sacrifice.

Histopathological findings:

effects observed, treatment-related

Description (incidence and severity):

changes in the structure of the liver due to the chronic exposure to the test material

Details on results (F1)

VIABILITY (OFFSPRING): No rats expired in this phase of the experiment.

CLINICAL SIGNS (OFFSPRING): No abnormal clinical sign were observed in any of the rats, either test or control, during the entire study period.

BODY WEIGHT (OFFSPRING): There was persistent statistically significant decrease in the rate of mean weekly body weight gain in the high dose rats, goth male and female, througout the experiment, for most weeks in the mid dose rats, both male and female, and for a few weeks in the low dose male rats. The body weight in all the test groups was significantly lower from the corresponding control groups even during zero week due to the fact that these animals came from dams already on various levels of the compound. The rats in the various groups at zero week had widely variable initial body weights because the corresponding Fo dams conceived - and gave birth - at different times.The difference between either the low dose groups and the control groups or the mid dose groups and the control groups is less than 10 % of the corresponding control weight during the last six weeks on test while both high dose groups differed by mor than 10 % from the beginning. Because of this factor we do not consider the low dose and the mid dose difference to be biologically significant.

SEXUAL MATURATION (OFFSPRING)

ORGAN WEIGHTS (OFFSPRING):
Heart: The mean cardiac weight of the high dose male rats was significantly lower than the control. However, there was no morphologic abnormalities observerd microscopically.
Liver: The mean liver weight of the mid and high dose male rats, as well as of all test female rats was significantly higher than the corresponding control rats.
Kidneys: The mean renal weights were not remarkable.
Gonads: The mean testicular weights were not remarkable, while the ovarian weight of the mid dose female group was significantly less than the control group. There was no accompanying histopathology, however, of the ovaries of the mid dose rats.
Brain: The mean brain weight of all the male test groups and of the high dose female group was significantly lower than the corresponding control weight. We do not consider this, hoever, to be of any biological significance since there was no accompanying histopathology of the brain.

GROSS PATHOLOGY (OFFSPRING): No pertinent gross pathology findings were observed in any of the Fla rats at terminal sacrifice.

HISTOPATHOLOGY (OFFSPRING): The most frequent finding was lymphocytosis of the lungs, either peribronchial or perivascular. This condition, endemic in this strain of rat, was seen in the control as well as in the test animals. The most significant finding, however, was the cloudy swelling of the liver seen in a dose dependent way in the mid dose and high dose rats, both male and female. This most likely implies an adaptive hyperplasia of the sub-cellular endoplasmic reticulum of the hepatic cells of the affected test groups.

OTHER FINDINGS (OFFSPRING):

Organ-to-body weight ratios:
Heart-to-body weight ratios: These were not remarkable.
Liver-to-body weight ratios: The ratios for both male and female test groups were considerably higher than the corresponding control values with a dose dependent pattern. The female ratios were slightly higher the the male ones.
Kidneys-to-body weight ratios: These were not remarkable.
Gonads-to-body weight ratios: These were not remarkable.
Brain-to-body weight ratios: These were not remarkable.

Clinical Chemistry:
FBS: Low dose female rat #1070 had an FBS of 260 mg/dl; histopathologically this rat was not remarkable.
BUN: All values, individual as well as mean, were normal.
SGOT: All values, individual as well as mean, were normal.
SGPT: The mean mid dose female and doth high dose male and female values were significantly higher than control. These differences are of no biological significance, however, since all mean as well as individual values except one were normal; high dose male rate #1117 had an SGPT value of 105. Histopathologically this rat exhibited mild pulmonary lymphocytosis.
GGTP: All values, individual as well as mean, were normal.
Total Protein: The mean value for the mid dose groups, male and female, as well as for the high dose groups, both male and female, was significantly higher than control. All mean as well as individual values except one were normal; mid dose female rat #1028 had a Total Protein value of 8.52 g/dl. Histopathologically this rat exhibited pulmonary lymphocytosis.

Hematology:
Hematological Value at 45 Days:
RBC: The mean total RBC counts in the mid dose and the high dose male test groups were significantly lower than the control. All values, however, mean as well as individual, were within our normal range.
HGB: The mean hemoglobin values of the mid dose and high dose male rats were significantly lower than the control, while the same value was higher than the control in the high dose female rats. All values, however, mean as well as individual, were within our established normal range.
HMCT: The mean HMCT values for the low and high dose group of male rats were statistically lower than the control, while the mean HMCT value for the high dose female group was statistically higher than the control. All values, however, mean as well as individual, were within normal range.
WBC Diff: All rats examined displayed normal differential counts.
Plat. Est.: The platelets of all rats examined were deemed to have been adequate.

Hematological Values at 91 Days:
RBC: All total RBC counts, as well as individual, were within normal range.
HGB: All HGB values, mean as well as individual, except one were within normal range; high dose female rat #1122 had a HGB of 11.6 g/dl; histologically this rat exhibited mild pulmonary lymphocytosis.
HMCT: All HMCT values, mean as well as individual, were within normal range.
WBC: The mean total WBC counts of the low and high dose groups were significantly higher than the control groups. All total WBC counts, however, mean as well as individual, were within normal range.
WBC Diff: All rats examined displayed a normal differential counts.
Plat. Est.: The platelet estimate of all rats examined were deemed to have been adequate.

Urinalysis:
Urinalysis at 45 days: There were no significant differences between the test and control groups, male or female, in any urinalysis parameters.
Urinalysis at 91 days: There were no significant differences between the test and control groups, male or female, in any urinalysis parameters.

Effect levels (F1)

Key result

Dose descriptor:

NOEL

Generation:

F1

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

haematology

histopathology: non-neoplastic

Target system / organ toxicity (F1)

Critical effects observed:

no

Overall reproductive toxicity

Reproductive effects observed:

no

Any other information on results incl. tables

The only pertinent findings observed in the F0 parents were:
a slight decrease in the mean weaning weight of both male and female pups of the high-dose group, a slight decrease in lactation indices of the high-dose group, decreased body weight and feed consumption of the high-dose female group and normal histology of the reproductive organs in the F0 parents. Fertility, viability and gestation indices were not affected.  In the reproduction phase of this experiment
there was a toxic effect at the 2,000 mg/kg/day level, a borderline effect at the 1,000 mg/kg/day level and no effect at 500 mg/kg/day.

Test item: Summary of F0/F1a Reproduction Data

Dose Group         Number of Dams                  Total Number of Pups
(mg/kg/day)        Mated        Conceived        Live-         Still   Day 4        Culled  
Day 21                     
                                        born    born        
   Day 4*
0                 20          20                 235          4        226          43          180
500                 20          20                 252          2        247          51          195
1000                 20          20                 229          0        220          37          173
2000                 20          19                 225          4        214          27          164
* Litters with more than 10 pups were culled to 10

Surfynol 104: Summary of F0/F1a Reproduction Data
(continued)
Dose Group    Avg. # of Pups/Litter          Avg. Pup
Weaning Weight (g)
(mg/kg/day)   Day 4           Weaned 
              M      F            M      F              Male        Female
0             6.0    5.4            4.6          4.5              45.7        44.2
500             6.6    5.8            5.0          4.8              42.0        40.9
1000             5.8    5.3            4.6          4.1              36.6        35.8
2000             5.5    5.8            4.1          4.6              28.8        25.7
The following pertinent findings were observed in the F1a rats: slight decrease in the mean rate of body weight gain in both sexes at the mid- and high-dose (there was also a significant decrease in this parameter in the low-dose male group during the first eight weeks), normal mean hematological findings, clinical chemistry findings, and urinalysis findings after 91 days on test, significant increase in the absolute and relative liver weights of both sexes at the mid- and high-dose, corresponding histopathology of the liver showing mild to moderate centrilobular cloudy swelling of hepatocytes of the mid- and high-dose rats.  Surfynol 104, when fed to rats under the conditions of this experiment, showed no effect at
500mg/kg/day but did have a toxic effect in the Fla generation at >1,000 mg/kg/day.

Applicant's summary and conclusion

Conclusions:

2,4,7,9-Tetramethyl-5-decyne-4,7-diol, when fed to rats under the conditions of an one generation reproductive toxicity study, showed no effect at 500 mg/kg/day.
At dose levels at greater than or equal to 1,000 mg/kg/day slightly decreased mean weaning weights, lacation indices and body weight gain were observed in the F1a generation.
There were no significant effects on the reproductive performance reported.

Executive summary:

The purpose of this study was to evaluate the possible toxicity of the test item, when fed to the rat during a single generation reproduction study and for ninety one days to the F1a weanlings. The test material was mixed into the rats’ feed to provide dose levels of 0, 500, 1000, and 2000 mg/kg/day. Sexually mature Sprague-Dawley albino rats were divided into four groups, each consisting of ten male and twenty female rats. All F0 male rats, both test and control, were fed their respective diets until their litters reached the age of 21 days for weaning, when the F0 dams were sacrificed. The weanlings were randomized to their respective groups and carried on the same dose levels to the termination of the experiment. The only pertinent findings observed in the F0 parents were: 1. Slight decrease in the mean weaning weight of both male and female pups of the high-dose group, 2. Slight decrease in lactation indices of the high-dose group, 3. Decreased body weight and feed consumption of the high-dose female group, 4. Normal histology of the reproductive organs in the F0 parents. The following pertinent findings were observed in the F1a rats: 1. Slight decrease in the mean rate of body weight gain in the mid- and high-dose male and female rats; there was also significant decrease in this parameter in the low-dose male group during the first eight weeks, 2. Normal mean hematological findings, clinical chemistry findings, and urinalysis findings after 91 days on test, 3. Significant increase in the liver weight of the mid- and high-dose male and female test groups with corresponding increase in the liver-to-body weight ratios, 4. Corresponding histopathology of the liver of the mid- and high-dose male and female rats, showing mild to moderate centrilobular cloudy swelling of hepatocytes.