2-hydroxy-5-octanoylbenzoic acid

Toxicity to reproduction

Administrative data

Endpoint:

screening for reproductive / developmental toxicity

Remarks:

based on test type (migrated information)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

07 July 2009 - 01 December 2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP study conducted according to OECD Guideline 421 with deviations: homogeneity analyses of the test solutions were not performed; food consumption was not measured for males post-mating

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 421 (Reproduction / Developmental Toxicity Screening Test)

Deviations:

yes

Remarks:

homogeneity analyses of the test solutions were not performed; food consumption was not measured for males post-mating

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

417-790-1

EC Name:

-

Cas Number:

78418-01-6

Molecular formula:

C15H20O4

IUPAC Name:

2-Hydroxy-5-(1-oxooctyl)benzoic acid

Constituent 2

Reference substance name:

MEXORYL SAB

IUPAC Name:

MEXORYL SAB

Details on test material:

- Name of test material (as cited in study report): Mexoryl SAB
- Physical state: Powder
- Analytical purity: 99.7 %
- Lot/batch No.: 0140799
- Date of receipt: 07 May 2009
- Expiration date of the lot/batch: March 2010
- Storage condition of test material: Ambient temperature

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: BIOAGRI Laboratorios, Brazil
- Age at study initiation: 10 weeks
- Weight at study initiation: Males: 335.45 g (295-384 g); Females: 205.97 g (178-231 g)
- Housing: Animals were housed 2 animals/sex/cage during acclimation and the premating period, 1 female with 1 male during the cohabitation period and individually after mating in polypropylene cages with wire lids and bedding material.
- Diet: Autoclaved Nuvilab CR-1 diet type for rats (Nuvital Nutrientes Ltda., Curitiba - PR, Brazil), ad libitum
- Water: Autoclaved drinking water, ad libitum
- Acclimation period: 9 days

ENVIRONMENTAL CONDITIONS
- Temperature: 19.2-25 °C
- Humidity: 30-70 %
- Air changes: 10-20 air changes per hour
- Photoperiod: 12 h dark / 12 h light

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

polyethylene glycol

Remarks:

PEG 300

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
- Test item, Mexoryl SAB, in solidified form (powder) at room temperature, was previously homogenized before use in this study.
- For each dosage group, the appropriate amount of the test item was weighed into a precalibrated beaker and the vehicle (PEG 300) was added in sufficient quantity to achieve the desired concentration. The prepared solutions were maintained at room temperature, protected from light and were stirred immedately before administration to animals.
- Test solutions were prepared daily and were used within 2 h after preparation.

STABILITY
- Stability of the test item in the vehicle at room temperature for a period of 5 days was verified. The test solutions were analysed immediately after preparation and also after 5 days of storage at room temperature.

DOSE VOLUME: 4 mL/kg bw/day

Details on mating procedure:

- M/F ratio per cage: 1:1
- Length of cohabitation: Until evidence of copulation or 2 weeks
- Proof of pregnancy: Presence of sperm in vaginal smear referred to as Day 0 of gestation.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

- Samples of each test item solution and control were drawn once during the study period for concentration analysis.

Results:
- Satisfactory agreement was observed between the nominal and actual concentration of the test item in the administered preparation except for the 10 mg/kg bw/day dose-level where the animals received slightly higher dose (difference of +13.26 %).

Duration of treatment / exposure:

Males:
- 2 weeks prior to mating, during the mating period and up to 5 weeks post-mating for a total of 50 days.

Females:
- 2 weeks prior to mating, during the mating period (up to 14 days), during gestation and at least 4 additional days during the lactation period for a total of 40 to 49 days.

Frequency of treatment:

Once daily

Details on study schedule:

- Acclimation 7 July 09
- Premating 16 july 09
- Mating 30 july 09 to 13 aug 09
- Delivery 22 aug 09 to 29 aug
- Necropsy:
Females 25 aug to 3 sep 09
Males 4 sep 09

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
10 mg/kg bw/day
Basis:
actual ingested

Doses / concentrations 2

Remarks:

Doses / Concentrations:
30 mg/kg bw/day
Basis:
actual ingested

Doses / concentrations 3

Remarks:

Doses / Concentrations:
100 mg/kg bw/day
Basis:
actual ingested

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: Dose levels were selected on the basis of the results of 4-week oral (gavage) toxicity study in rats where Mexoryl SAB was administered at 10, 30, 100 or 200/300 mg/kg bw/day. In this study, the high dose group was dropped from 300 to 200 mg/kg bw/day on Day 13 of the treatment period because of adverse clinical signs including death of 4 males and 1 female.
- Rationale for animal assignment: Allocation of the animals to groups (after acclimation) was made by randomization using the Statistical Analysis System.

Positive control:

Not applicable

Examinations

Parental animals: Observations and examinations:

CAGE SIDE AND CLINICAL OBSERVATIONS: Yes
Time schedule:
- Animals were observed twice daily for mortality, morbidity, pertinent behavioral changes, signs of difficult or prolonged parturition and all signs of overt toxicity, except on Saturdays and Sundays, when each animal was observed once daily.
- General clinical observations were made at least once a day.

BODY WEIGHT: Yes
Time schedule for examinations:
- Males were weighed on the first day of dosing and twice per week thereafter.
- Females were weighed on the first day of dosing, twice per week during the premating period, on Days 0, 3, 7, 10, 14, 17 and 20 of gestation and during lactation on the same days as the weighing of litters (on postnatal Days 0 and 4).
- Animals were not weighed during mating period.

FOOD CONSUMPTION:
Time schedule: Food consumption was determined weekly during the treatment period.

Oestrous cyclicity (parental animals):

None

Sperm parameters (parental animals):

None

Litter observations:

- Live pups were counted, sexed and weighed on postnatal Days 0 and 4.
- Pups were observed daily for mortality and clinical signs or abnormal behavior.
- External examination of the pups was performed.

Postmortem examinations (parental animals):

SACRIFICE AND GROSS NECROPSY:
- On completion of the treatment period, all parental animals were euthanized by CO2 inhalation and were examined macroscopically for any structural abnormalities or pathological changes.
- In all females, the number of implantation sites and corpora lutea was recorded (whenever possible).

ORGAN WEIGTHS
- Testes and epididymides of all males and uterus+cervix and ovaries of the females were weighed.

HISTOPATHOLOGY
- At scheduled necropsy, the following organs of all animals was preserved in 10 % buffered formalin: testes, epididymides, ovaries, prostate, seminal vesicle and coagulating gland, bulbourethral gland, uterus and organs showing alterations.
- Full histopathology of the ovaries, uterus, testes and epididymides were performed in high dose and control animals. These examinations were not extended to animals of other dosage groups, because treatment-related changes were not observed in the high dose group. All gross lesions were examined.

Postmortem examinations (offspring):

All pups were grossly examined for abnormalities of the thoracic and abdominal organs.

Statistics:

- Quantitative variables such as body weights, food consumption, organs weights, number of fetuses and corpora lutea were analyzed by One Way Analysis of Variance (ANOVA), followed by Dunnett's test if significance was detected, or by non- parametric test of Kruskal-Wallis, according to the results of tests for normality and homogeneity of variance.
- Chi-Square Test was used for statistical evaluation of clinical findings, macroscopic and microscopic findings, loss offspring and reproductive index.
- Level of significance was set at 5 %, and the statistical program used was SAS Software (SAS Institute Inc., Cary, USA).

Reproductive indices:

- Pre-implantation loss: [(Number of corpora lutea - Number of implantation sites) / Number of corpora lutea] X 100
- Post-implantation loss: [(Number of implantation sites - Number of live concepti) / Number of implantations] X 100
- Mating index: [Number of females paired / Number of females mated] X 100
- Fertility index: [Number of females that showed evidence of mating/ Number of females achieved gestation and delivered alive pups] X 100
- Gestation index: [Number of females with live born pups / Number of pregnant females] X 100

Offspring viability indices:

- Live birth index: [Number of live born pups / Number of delivered pups] X 100
- Viability index on Day 4 post-partum: [Number of surviving pups on Day 4 post-partum / Number of live born pups] X 100
- Mean sex ratio (male): (Male pups/ Total pups) X 100

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

no effects observed

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Other effects:

not specified

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)
- No mortality and no test item treatment-related clinical signs were noted during the study.
- Some clinical signs like hypotrichosis, alopecia, epistaxis and stertoreous breathing were observed in some control and/or treated animals, with similar incidence. These findings are commonly observed in laboratory rats, not dose related in incidence and were therefore considered not to be treatment related.

BODY WEIGHT (PARENTAL ANIMALS)
- Body weight and body weight gain were unaffected by treatment with the test item throughout the treatment period, both in males and females, with the exception of dams at the 10 mg/kg bw/day dose-level. At this dose-level, during gestation Days 17 to 20, body weight gains were statistically significantly increased compared to the control group. This finding was considered incidental.

FOOD CONSUMPTION (PARENTAL ANIMALS)
- Food consumption was considered unaffected by the test-item in females throughout the study.
- Food consumption was statistically higher (+ 8.4-10.1 %) during premating period for male groups at 10 and 30 mg/kg bw/day, when compared to control. These differences were of minimal amplitude, not dose related and are thus considered unrelated to treatment with test item.

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS)
Mating data:
- Mating index was 100 % at all dose-levels.
- One female, treated at 30 mg/kg bw/day, did not show evidence of mating but achieved pregnancy and delivered alive, healthy pup on the 8th day of the post mating period.
- Mean number of days of pairing before mating was comparable between the different dose-levels. Thus, there was no test item treatment-related difference between controls and test item-treated groups.

Fertility data:
- Fertility index was unaffected by the treatment with the test item (70, 80, 80 and 80 % at the dose-levels of 0, 10, 30 and 100 mg/kg bw/day, respectively).
- For the control group, 3/10 mated females were not pregnant, compared to 2/10, 2/10 and 2/10 at 10, 30 and 100 mg/kg bw/day, respectively.

Delivery data:
- Gestation index was 100 % in all groups.
- Mean duration of gestation was similar between groups, and was of 20.4, 20.4, 20.6 and 20.9 days at the dose-levels of 0, 10, 30 and 100 mg/kg bw/day, respectively.
- Duration of gestation for each female remained within the physiological range (i.e. 21 or 22 days after mating) except one female in the 100 mg/kg bw/day group which had a pregnancy of 23 days.
- Mean numbers of corpora lutea as well as the mean number of implantation sites were unaffected by the treatment with the test item. One female presented with corpora lutea, although it was not pregnant.
- Mean number of live pups per litter was similar among all groups.

ORGAN WEIGHTS (PARENTAL ANIMALS)
- No significant findings on absolute or relative organ weights were observed.
- Only statistically significant finding was for the right ovary of the dams at 30 mg/kg bw/day. Relative right ovary weights were 8 % lower than the control group. This finding of minimal amplitude was not considered treatment related because there was no associated microscopic changes and no dose response relationship.

GROSS PATHOLOGY (PARENTAL ANIMALS)
- No macroscopic findings related to the test item treatment were observed.

HISTOPATHOLOGY (PARENTAL ANIMALS)
- No histopathological findings related to the test item treatment were observed.
- Sporadic microscopic findings were observed in females only. These findings occurred with very low incidence, both in control and treated groups, and were therefore considered of no toxicological importance and unrelated to treatment with the test item.

Effect levels (P0)

Dose descriptor:

NOEL

Effect level:

100 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No substance-related adverse effects were observed at any of the dose levels.

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Sexual maturation:

no effects observed

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

Details on results (F1)

VIABILITY (OFFSPRING)
-Live birth index was 98.43, 100, 100 and 100 % at 0, 10, 30 and 100 mg/kg bw/day, respectively.
- Viability index on post natal Day 4 was 96.87, 98.92, 100 and 100 % at 0, 10, 30 and 100 mg/kg bw/day, respectively. The deaths in the control and low dose groups were considered incidental and not related to treatment.

CLINICAL SIGNS (OFFSPRING)
- No test item treatment-related clinical signs were noted in pups.

BODY WEIGHT (OFFSPRING)
- No differences were observed in mean pup body weight on postnatal Days 0 and 4 between the control and the test-item treated groups.
- Pups weight gain (Day 0 to 4) was therefore similar between the groups.

SEX RATIO (OFFSPRING)
- Sex ratio of the pups was unaffected by treatment with the test-item at any dose-level.

GROSS PATHOLOGY (OFFSPRING)
- No external malformations were observed in pups found dead or euthanized on Day 4 post partum. Pale liver of reduced size was observed in only one fetus from the 30 mg/kg bw/day group and this finding was regarded as incidental.

Effect levels (F1)

Dose descriptor:

NOEL

Generation:

F1

Effect level:

100 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No substance-related adverse effects were observed at any of the dose levels.

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

Table 7.8.1/1: Summary of reproductive data

Reproductive data	Control	10 mg/kg bw/day	30 mg/kg bw/day	100 mg/kg bw/day
Pairs started (N)	10	10	10	10
Mated Females (N)	10	10	10	10
Mean days of pairing before mating	2.2	2.4	3.6	3.2
Conceiving days 1-5 (N)	10	10	7	9
Conceiving days 6-14(N)	0	0	2	1
Conceiving day unknown (N)*	0	0	1*	0
Females achieving Pregnancy (N)	7	8	8	8
Pregnancy ≤ 21 days (N)	6	8	7	7
Pregnancy = 22 days (N)	1	0	0	0
Pregnancy ≥ 22 days (N)	0	0	0	1
Pregnancy unknown duration (N)*	0	0	1*	0
Dams with live young born (N)	7	8	8	8
Dams with live young born at Day 4 (N)	7	8	8	8

 

* One female did not show evidence of mating but achieved pregnancy and delivered live pups.

Table 7.8.1/2: Summary of the offspring findings

Day 0	Control		10 mg/kg bw/day		30 mg/kg bw/day		100 mg/kg bw/day
Total number of live pups delivered	64		93		82		73
Live pups/dam (mean)	9.1		11.6		10.3		9.1
Live birth index (%)	98.43		100		100		100
Mean sex ratio (male)	N	Sex ratio	N	Sex ratio	N	Sex ratio	N	Sex ratio
	26	40.6	59	63.4	37	45.1	38	52.0
Day 4	Control		10 mg/kg bw/day		30 mg/kg bw/day		100 mg/kg bw/day
Total number of live pups	62		92		82		73
Live pups/dam (mean)	8.9		11.5		10.3		9.1
Viability index	96.87		98.92		100		100
Mean sex ratio (male)	N	Sex ratio	N	Sex ratio	N	Sex ratio	N	Sex ratio
	26	41.9	59	64.1	37	45.1	38	52.0

Applicant's summary and conclusion

Conclusions:

Under the test conditions, the No Observed Effect Level (NOEL) of Mexoryl SAB was higher to 100 mg/kg bw/day for parental toxicity, embryo-fetal developmental toxicity and pup development until Day 4 post-partum in Wistar Hannover rats.

Executive summary:

In a reproduction/developmental toxicity screening study performed according to OECD Guideline 421 and in compliance with GLP, Mexoryl SAB was administered by oral gavage to groups (10/sex/dose) of Wistar Hannover rats at the dose levels of 0, 10, 30 and 100 mg/kg bw/day as a solution in the vehicle (PEG300) with the dose volume of 4 mL/kg bw/day, for 2 weeks before mating, during mating, gestation and until day 4 post-partum for the females, and for 2 weeks before mating, during mating and 22-35 days after the last day of mating for males. Mortality, clinical signs, body weight change, food consumption, reproductive performance, organ weights, macroscopic and microscopic examination were examined in parental animals. The pups were observed daily for clinical signs, sexed and weighed on Days 0 and 4 post partum and sacrificed on Day 4 post partum and subjected for macroscopic examination.

No mortality and no clinical signs attributed to treatment with the test item were observed. No effects on body weight or food consumption were observed. The reproductive performance of males and females, mating, fertility, gestation and live birth indices were similar to that of the control group. No treatment-related effects were noted on weights of testes, epididymides, ovaries, uterus and cervix and no treatment-related findings were recorded at necropsy or microscopic examination. The test item treatment had no effects on the clinical condition of the pups, body weight or sex ratio. No macroscopic findings were observed in the pups sacrificed on Day 4 post-partum.

Under the test conditions, the No Observed Effect Level (NOEL) of Mexoryl SAB was considered to be 100 mg/kg bw/day for parental toxicity, embryo-fetal developmental toxicity and pup development until Day 4 post-partum in Wistar Hannover rats.