Registration Dossier

Administrative data

Endpoint:
toxicity to reproduction: other studies
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
19 June to 10 July 1995
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Similar to guideline study (with certain deviations), to GLP; on related material

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1996
Report Date:
1996

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
other: EPA OPPTS 870.3700 (Prenatal Developmental Toxicity Study)
Deviations:
yes
Remarks:
foetuses not examined, groups of 15 animals used (not the indicated 20)
GLP compliance:
yes
Type of method:
in vivo

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): trisodium EDDS (under code)
- Molecular formula (if other than submission substance): C10-H13-N2-O8. 3Na
- Molecular weight (if other than submission substance): 358
- Smiles notation (if other than submission substance): [Na+].[Na+].[Na+].OC(=O)[C@H](CC([O-])=O)NCCNC(CC([O-])=O)C([O-])=O
- Substance type: technical product
- Physical state: yellow liquid
- Purity test date: no data
- Lot/batch No.: .01
- Expiration date of the lot/batch: 1 January 1998
- Stability under test conditions: no data
- Storage condition of test material: room temperature

Test animals

Species:
rat
Strain:
other: Sprague-Dawley derived Crl:CD VAF/Plus
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories, Portage, Michigan, USA
- Age at study initiation: 12.5 weeks
- Weight at study initiation: 225-280 g
- Fasting period before study: no
- Housing: individually in stainless steel wire-mesh cages
- Diet (e.g. ad libitum): conventional, ad libitum
- Water (e.g. ad libitum): tap water, ad libitum
- Acclimation period: 10 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-22
- Humidity (%): 54-68
- Air changes (per hr): "environmentally controlled room"
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: From: 19 June 1995 To: to 10 July 1995

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
water
Details on exposure:
PREPARATION OF DOSING SOLUTIONS: the test substance was weighed into a beaker and dissolved in distilled water then made up to the required volume with distilled water.



Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Sent away for analysis; details of results are not included in the report
Duration of treatment / exposure:
day 6-15 of gestation
Frequency of treatment:
daily
Duration of test:
dosing occurred from gestation days 6-15 (study termination)
Doses / concentrations
Remarks:
Doses / Concentrations:
0, 50, 400 or 1000 mg/kg bw/day
Basis:
nominal conc.
No. of animals per sex per dose:
15 females
Control animals:
yes, concurrent vehicle
Details on study design:
Female rats were mated on a 1:1 basis with males of the same source and strain; the presence of a vaginal plug was taken as day 0 of pregnancy. The dams were then housed individually and on gestation days 6-15 dosed with the test substance by oral gavage at a constant volume of 10.0 mL/kg bw/day. The animals were observed twice daily for overt signs of toxicity. Body weights and food consumption were recorded on days 0, 6, 9, 12 and 15. About 2 and 4 h after the last dose, blood samples were taken from each animal and analysed for copper, iron and zinc levels. A complete gross necropsy was carried out on each dam.
Statistics:
Pairwise statistical analysis was used to compare the treatment groups with the control group. Parameters were analysed using one-way analysis of variance, which if significant were subjected to Dunnett's t-test for pairwise comparisons.

Results and discussion

Effect levels

Dose descriptor:
NOAEL
Effect level:
ca. 400 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
female
Basis for effect level:
other: maternal toxicity: soft feces, reduction in food consumption and weight gain at 1000 mg/kg bw/day

Observed effects

No deaths occurred during the study. Soft feces were observed in five animals at the high-dose. No other clinical observations were considered to be treatment-related. Body weight gain was slightly reduced in a dose-dependent manner during the dosing period (days 6-15) and during the study period (days 0-15). Food consumption was reduced for the first three days of dosing (days 6-9) in the high-dose group (p< 0.05).

A statistically significant (p

Applicant's summary and conclusion

Conclusions:
In a GLP study, conducted according to a protocol similar to EPA Guidelines (OPPTS 870.3700), trisodium EDDS caused a dose-related and statistically significant reduction in plasma levels of copper and zinc, but no such reductions in plasma iron levels were seen. Maternal toxicity, evident as soft faeces and a slight reduction in body weight gain, was seen at 1000 mg/kg bw/day (the highest tested dose), therefore 400 mg/kg bw/day considered the study NOAEL.
Executive summary:

In a GLP study, conducted according to a protocol similar to EPA Guidelines (OPPTS 870.3700), trisodium EDDS was assessed for its potential to cause maternal toxicity and alter plasma levels of copper, iron and zinc following oral administration in pregnant Charles River rats. Groups of 15 female rats were administered 0, 50, 400 or 1000 mg/kg bw/day of the test substance by oral gavage from gestation day 6 to 15. The animals were observed for signs of clinical toxicity throughout the study and at regular intervals body weights and food consumption were recorded. Blood samples were taken 2 and 4 h after the last dose on day 15 and analysed for plasma levels of copper, iron and zinc. The dams were examined for gross abnormalities of the major organs; no examination of the fetuses took place.

No deaths occurred during the study. Soft feces were observed in five animals at the high-dose but no other clinical observations were considered to be treatment-related. Body weight gain was slightly reduced in a dose-dependent manner and food consumption was reduced for the first three days of dosing in the high-dose group. A statistically significant, dose-related reduction in plasma zinc levels was evident in all treatment groups compared to the controls at both the 2 and 4 h sampling times. Plasma copper levels were reduced in all treatment groups, reaching significance at 4 h in the low-dose group and at both time points in the mid- and high-dose groups. No statistically significant or dose-related reductions in plasma iron levels were seen.

In conclusion, trisodium EDDS caused maternal toxicity, evident as soft faeces and a slight reduction in body weight gain at 1000 mg/kg bw/day, and caused a dose-related, statistically significant reduction in plasma levels of copper and zinc when given orally to pregnant rats on days 6-15 of gestation. No statistically significant or dose-related reductions in plasma iron levels were seen.

[Data on trisodium EDDS is considered relevant to use for understanding the potential toxicity of reproduction, mineral levels of EDDS acid, and is acceptable for using as read-across information.]