Sodium hydrogen-5-sulphoisophthalate

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Link to relevant study records

Reference

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16 July 2012 to 27 September 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

other: US EPA OPPTS 870.3650, July 2000

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

other: CrI:WI(Han) (outbred, SPF-Quality)

Sex:

male/female

Details on test animals or test system and environmental conditions:

Refer to Section 7.5.1

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

Refer to Section 7.5.1

Details on mating procedure:

Females were caged together with males on a one-to-one-basis in Macrolon plastic cages (MIII type, height 18 cm).

Post-mating Males were housed in their home cage (Macrolon plastic cages, MIV type, height 18 cm) with a maximum of 5 animals/cage. Females were individually housed in Macrolon plastic cages (MIII type, height 18 cm).

Following a minimum of 14 days of exposure for the males and females, one female was cohabitated with one male of the same treatment group, avoiding sibling mating. Detection of mating was confirmed by evidence of sperm in the vaginal lavage or by the appearance of an intravaginal copulatory plug. This day was designated Day 0 post-coitum. Once mating occurred, the males and females were separated. A maximum of 14 days was allowed for mating, after which females who had not shown evidence of mating were separated from their males. Detection of mating was not confirmed for animal nos. 43 (Group 1), 58 (Group 2) and 62 (Group 3) which did deliver live offspring. The mating date of these animals were estimated at 21 days prior to the actual delivery dates. These days were designated Day 0 post-coitum.

The females were allowed to litter normally. Day 1 of lactation was defined as the day when a litter was found completed (i.e. membranes and placentas cleaned up, nest build up and/or feeding of pups started). Females that were littering were left undisturbed.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Refer to Section 7.5.1

Duration of treatment / exposure:

After acclimatization, four groups of ten male and ten female Wistar Han rats were exposed by oral gavage to the test substance at 0, 100, 300 and 1000 mg/kg/day. Males were exposed for 29 days, i.e. 2 weeks prior to mating, during mating, and up to termination. Females were exposed for 43 - 53 days, i.e. during 2 weeks prior to mating, during mating, during post-coitum, and during at least 4 days of lactation.

Frequency of treatment:

Refer to Section 7.5.1

Details on study schedule:

Males were exposed for 29 days, i.e. 2 weeks prior to mating, during mating, and up to the day prior to scheduled necropsy. Females were exposed for 43-53 days, i.e. during 2 weeks prior to mating, during mating, during post-coitum, and during at least 4 days of lactation (up to the day prior to scheduled necropsy). Female nos. 41, 43 (Group 1), 62 , 70 (Group 3) and 77 (group 4) were not dosed during littering.

Dose / conc.:

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

Remarks:

Low dose group

Dose / conc.:

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

Remarks:

Mid dose group

Dose / conc.:

1 000 mg/kg bw/day (actual dose received)

Remarks:

High dose group

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Details on study design:

PREPARATION OF DOSING SOLUTIONS:

Formulations (w/w) were prepared daily within 6 hours prior to dosing and were homogenized to a visually acceptable level. No adjustment was made for specific gravity/density of the test substance, vehicle, and/or formulation. No correction was made for the purity/composition of the test substance.

Doses were administered by plastic feeding tube.

Dose volume: 5 mL/kg

Positive control:

None

Parental animals: Observations and examinations:

Male number paired with, mating date, confirmation of pregnancy, and delivery day were recorded. Pregnant females were examined to detect signs of difficult or prolonged parturition, and cage debris of pregnant females was examined to detect signs of abortion or premature birth. Any deficiencies in maternal care (such as inadequate construction or cleaning of the nest, pups left scattered and cold, physical abuse of pups or apparently inadequate lactation or feeding) were examined.

Oestrous cyclicity (parental animals):

Not determined

Sperm parameters (parental animals):

Parameters examined in selected 5 male parental animals:

testis weight, epididymis weight, prostate weight (after at least 24 h fixation), and weight of seminal vesicles including the coagulating glands

Refer to Section 7.5.1 for all histopathological analyses conducted in this study.

Litter observations:

Each litter was examined for the following if practicle and possible:

Mortality / Viability
The numbers of live and dead pups on Day 1 of lactation and daily thereafter were determined. If possible, defects or cause of death were evaluated.

Clinical signs

At least once daily, detailed clinical observations were made for all animals.

Body weights
Live pups were weighed on Days 1 and 4 of lactation.

Sex
Sex was determined for all pups on Days 1 and 4 of lactation.

Postmortem examinations (parental animals):

Refer to Section 7.5.1 of this IUCLID file

Postmortem examinations (offspring):

Necropsy

Pups surviving to planned termination were killed by decapitation on Days 5-7 of lactation. All pups were sexed and descriptions of all external abnormalities were recorded. The stomach was examined for the presence of milk. If possible, defects or cause of death were evaluated.

Statistics:

Refer to Section 7.5.1 of this IUCLID file

Reproductive indices:

Mating index (%): No. females mated / No. females paired x 100
Fertility index (%): No. pregnant females / No. of females placed x 100
Conception index (%): No. pregnant females / No. females mated x 100
Gestation index (%): No. females bearing live pups / No. pregnant females x 100
Duration ofgestation: No. days between confirmation of mating and the beginning of parturition.

Offspring viability indices:

Percentage live males at first litter check.
Percentage live females at first litter check.
Percentage of postnatal loss.
Viability index (%): No. live pups before necropsy / No. of pups born alive x 100

Clinical signs:

no effects observed

Description (incidence and severity):

Refer to Section 7.5.1 of this IUCLID file

Body weight and weight changes:

no effects observed

Description (incidence and severity):

Refer to Section 7.5.1 of this IUCLID file

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

Refer to Section 7.5.1 of this IUCLID file

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Refer to Section 7.5.1 of this IUCLID file

Other effects:

not examined

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Refer to Section 7.5.1 of this IUCLID file for a more complete description of results.

Reproductive results:

No reproduction toxicity was observed up to the highest dose level tested (1000 mg/kg). No treatment-related toxicologically relevant changes were noted in any of the reproductive parameters investigated in this study (i.e. mating, fertility and conception indices, precoital time, and numbers of corpora lutea and implantation sites).

Dose descriptor:

NOAEL

Effect level:

>= 1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Based on a lack of significant reproductive effects measured in the study.

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

no effects observed

At 1000 mg/kg bw/day, sex ratio of the pups indicated more female than male pups (62% female pups compared to 47% of the control group); this was statistically significantly different from controls.

No treatment-related changes were noted in any of the remaining developmental parameters investigated in this study (i.e. gestation index and duration, parturition, maternal care and early postnatal pup development consisting of mortality, clinical signs, body weight and macroscopy).

Key result

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Key result

Critical effects observed:

no

Key result

Reproductive effects observed:

no

Reproduction data summary

	Control	100 mg/kg	300 mg/kg	1000 mg/kg
Females paired	10	10	10	10
Females mated	10	9	10	9
Females non-mated	0	1	0	1
Pregnant females	9	9	10	9
Non-pregnant females	1	0	0	0
Females with living pups on Day 1	9	9	10	9
Mating index (%)	100.0	90.0	100.0	90.0
Fertility index (%)	90.0	90.0	100.0	90.0
Conception index (%)	90.0	100.0	100.0	100.0
Gestation index (%)	100.0	100.0	100.0	100.0

Conclusions:

A screening study for development and reproduction toxicity was performed according to OECD guideline 422 and GLP principles. No significant reproductive toxicity was noted up to a dose of 1000 mg/kg bw/d. The NOAEL for reproductive toxicity was concluded to be1000 mg/kg bw/day.

Executive summary:

A screening study for development and reproduction toxicity was performed according to OECD guideline 422 and GLP principles. No reproduction toxicity was observed up to the highest dose level tested (1000 mg/kg bw/day). No treatment-related toxicologically relevant changes were noted in any of the reproductive parameters investigated in this study (i.e. mating, fertility and conception indices, precoital time, and numbers of corpora lutea and implantation sites). The NOAEL for reproductive toxicity was concluded to be1000 mg/kg bw/day.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 000 mg/kg bw/day

Study duration:

subacute

Species:

rat

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

In an OECD 422 guideline study, the subject material was administered daily by gavage to groups of 10 each male and female rats at dose levels of 0 (control), 100, 300 or 1000 mg/kg bw/day. Males were exposed for 2 weeks prior to mating, during mating, and up to termination (for 28 days). Females were exposed for 2 weeks prior to mating, during mating, during post-coitum, and for at least 4 days of lactation (43 -53 days).

 

No reproduction toxicity was observed up to the highest dose level tested (1000 mg/kg). No treatment-related toxicologically relevant changes were noted in any of the reproductive parameters investigated in this study (i.e. mating, fertility and conception indices, precoital time, and numbers of corpora lutea and implantation sites).

Short description of key information:
An OECD 422 test (combined repeated dose toxicity with reproductive / developmental toxicity) conducted by oral gavage was conducted on the subject material.

Justification for selection of Effect on fertility via oral route:
Lack of significant reproductive effects were reported in a guideline study (OECD 422).

Effects on developmental toxicity

Description of key information

An OECD 422 test (combined repeated dose toxicity with reproductive / developmental toxicity) conducted by oral gavage was conducted on the subject material.

Link to relevant study records

Reference

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16 July 2012 to 27 September 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

equivalent or similar to guideline

Guideline:

other: OECD 422, Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

other: CrI:WI(Han) (outbred, SPF-Quality)

Details on test animals or test system and environmental conditions:

Refer to Section 7.5.1 of this IUCLID file

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

Refer to Section 7.5.1 of this IUCLID file

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Refer to Section 7.5.1 of this IUCLID file

Details on mating procedure:

Refer to Section 7.5.1 and 7.8.1 of this IUCLID file

Duration of treatment / exposure:

Refer to Section 7.5.1 and 7.8.1 of this IUCLID file

Frequency of treatment:

Refer to Section 7.5.1 and 7.8.1 of this IUCLID file

Duration of test:

Refer to Section 7.5.1 and 7.8.1 of this IUCLID file

Dose / conc.:

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

Remarks:

Low dose group

Dose / conc.:

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

Remarks:

Mid dose group

Dose / conc.:

1 000 mg/kg bw/day (actual dose received)

Remarks:

High dose group

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Details on study design:

Refer to Section 7.5.1 and 7.8.1 of this IUCLID file

Maternal examinations:

Refer to Section 7.5.1 and 7.8.1 of this IUCLID file

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: No
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: No
- Number of late resorptions: No

Fetal examinations:

Not applicable

Statistics:

Refer to Section 7.5.1 and 7.8.1 of this IUCLID file

Indices:

Liters (total)
Duration of gestation
Dead pups at first litter check
Living pups at first litter check
Postnatal loss
Viability index (%)

Details on maternal toxic effects:

Maternal toxic effects:no effects. Remark: Refer to Section 7.5.1 of this IUCLID file

Dose descriptor:

NOAEL

Effect level:

300 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

other: developmental toxicity

Key result

Abnormalities:

no effects observed

Reduction in number of live offspring:

effects observed, non-treatment-related

Description (incidence and severity):

Three pups of the control group and one pup at 300 mg/kg were found dead on Day 1 or missing on Day 2 of lactation. Pups missing were most likely cannibalised. No toxicological relevance was attributed to these dead/missing pups since the mortality incidence did not show a dose-related trend and remained within the range considered normal for pups of this age.

Changes in sex ratio:

effects observed, treatment-related

Description (incidence and severity):

At 1000 mg/kg bw/day, sex ratio of the pups indicated more female than male pups (62% female pups compared to 47% of the control group); this was statistically significantly different from controls. The laboratory’s historical control data (97 screening studies, years 2008-2012) includes two studies in which a comparable percentage of female pups was noted. As these two historical studies show the ultimate limit of the historical control data range, a possible relationship to treatment could not be excluded for the changed sex ratio in the current study. This was strengthened by the fact that seven out of nine litters in this group showed more female than male pups. The change in sex ratio may be indicative of a decrease in anogenital distance for the male pups leading to a ‘misclassification’ into female pups, rather than a direct effect on sex ratio (sexing was done using anogenital distance).

Changes in litter size and weights:

no effects observed

Anogenital distance of all rodent fetuses:

effects observed, treatment-related

Description (incidence and severity):

See remark under "changes in sex ratio". The change in sex ratio may be indicative of a decrease in anogenital distance for the male pups leading to a ‘misclassification’ into female pups, rather than a direct effect on sex ratio.

Changes in postnatal survival:

no effects observed

External malformations:

no effects observed

Description (incidence and severity):

At macroscopic examination, no milk in the stomach was noted for three litters of the control group, one litter at 100 mg/kg bw/day and four litters (not all pups) at 300 mg/kg. This was not considered to be treatment related or toxicologically relevant since no dose response relationship was noted, it also occurred in the control group, and these pups survived until the scheduled necropsy, indicating they were all sufficiently fed during lactation. This finding for the animals surviving to the scheduled necropsy is likely secondary to the time when the actual necropsies were performed, and is not attributable to treatment.

Key result

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

changes in sex ratio

Key result

Abnormalities:

effects observed, treatment-related

Localisation:

external: anogenital distance

Description (incidence and severity):

A change in sex ratio was observed, which may be indicative of a decrease in anogenital distance for the male pups leading to a ‘misclassification’ into female pups (rather than a direct effect on sex ratio).

Key result

Developmental effects observed:

yes

Lowest effective dose / conc.:

1 000 mg/kg bw/day (actual dose received)

Treatment related:

yes

Relation to maternal toxicity:

developmental effects in the absence of maternal toxicity effects

Dose response relationship:

no

Relevant for humans:

yes

Developmental data summary

	Control	100 mg/kg	300 mg/kg	1000 mg/kg
Litters
Total	9	9	10	9
Dration of gestation
Mean	21.3	21.1	21.3	21.3
St Dev	0.5	0.6	0.5	0.5
N	9	9	10	9
Dead pups at first litter check
Litters affected (%)	1	0	0	0
Total	1	0	0	0
Mean	0.1	0	0	0
St Dev	0.3	0.0	0.0	0.0
N	9	9	10	9
Living pups at first litter check
% males/%females	53/47	53/47	54/46	38/62#
Total	93	104	92	102
Mean	10.3	11.6	9.2	11.3
St Dev	2.5	3.2	3.7	2.9
N	9	9	10	9
Postnatal loss
% of living pups	2.2	0.0	1.1	0.0
Litters affected (No.)	1	0	1	0
Total (No.)	2	0	1	0
Mean	0.2	0.0	0.1	0.0
St Dev	0.7	0.0	0.3	0.0
N	9	9	10	9
Viability Index (No.)	97.8	100.0	98.9	100.0

# Fischer's exact test significance at 5%

Conclusions:

A screening study for development and reproduction toxicity was performed according to OECD guideline 422 and GLP principles. Developmental toxicity was observed at 1000 mg/kg bw/day as a possible relationship to treatment could not be excluded for the change in sex ratio. The NOAEL for developmental effects was 300 mg/kg bw/day.

Executive summary:

A screening study for development and reproduction toxicity was performed according to OECD guideline 422 and GLP principles. At 1000 mg/kg, sex ratio of the pups indicated more female than male pups (62% female pups compared to 47% of the control group); this was statistically significantly different from controls. The laboratory’s historical control data (97 screening studies, years 2008-2012) includes two studies in which a comparable percentage of female pups was noted. As these two historical studies show the ultimate limit of the historical control data range, a possible relationship to treatment could not be excluded for the changed sex ratio in the current study. This was strengthened by the fact that seven out of nine litters in this group showed more female than male pups.

It should be noted that this change in sex ratio may be indicative of a decrease in anogenital distance for the male pups leading to a ‘misclassification’ into female pups, rather than a direct effect on sex ratio.

No treatment-related changes were noted in any of the remaining developmental parameters investigated in this study (i.e. gestation index and duration, parturition, maternal care and early postnatal pup development consisting of mortality, clinical signs, body weight and macroscopy).

Effect on developmental toxicity: via oral route

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

300 mg/kg bw/day

Study duration:

subacute

Species:

rat

Effect on developmental toxicity: via inhalation route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via dermal route

Endpoint conclusion:

no study available

Additional information

In an OECD 422 guideline study, the subject material was administered daily by gavage to groups of 10 each male and female rats at dose levels of 0 (control), 100, 300 or 1000 mg/kg bw/day. Males were exposed for 2 weeks prior to mating, during mating, and up to termination (for 28 days). Females were exposed for 2 weeks prior to mating, during mating, during post-coitum, and for at least 4 days of lactation (43 -53 days).

 

At 1000 mg/kg, the sex ratio of the pups indicated more female than male pups (62% female pups compared to 47% of the control group); this was statistically significantly different from controls. The laboratory’s historical control data (97 screening studies, years 2008-2012) includes two studies in which a comparable percentage of female pups was noted. As these two historical studies show the ultimate limit of the historical control data range, a possible relationship to treatment could not be excluded for the changed sex ratio in the current study. This was strengthened by the fact that seven out of nine litters in this group showed more female than male pups.

It should be noted that this change in sex ratio may be indicative of a decrease in anogenital distance for the male pups leading to a ‘misclassification’ into female pups, rather than a direct effect on the sex ratio.

No treatment-related changes were noted in any of the remaining developmental parameters investigated in this study (i.e. gestation index and duration, parturition, maternal care and early postnatal pup development consisting of mortality, clinical signs, body weight and macroscopy).

Justification for selection of Effect on developmental toxicity: via oral route:
Significant developmental effects were reported in a guideline study (OECD 422).

Justification for classification or non-classification

Based on a lack of significant reproductive effects noted in an OECD 422 study in rats, no classification of the test material for reproductive effects is warranted.

Based on significant developmental effects noted in an OECD 422 study in rats, the subject material receives a classification under the EU Dangerous Substance Directive (67/548/EEC) of Repr. Cat. 3; R63 (Possible risk of harm to the unborn child). Classification under the EU Regulation 1272/2008 results in a Repr. Cat. 2 (H361: Suspected of damaging fertility or the unborn child).