Sodium N-(hydroxymethyl)glycinate

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Link to relevant study records

Reference

Endpoint:

toxicity to reproduction

Remarks:

other: 90-day oral toxicity study

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study according to internationally accepted guidelines.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: EPA OPP 82-1 (90-Day Oral Toxicity)

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Route of administration:

oral: gavage

Vehicle:

water

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

90 days

Frequency of treatment:

Daily

Remarks:

Doses / Concentrations:10, 40, 160 mg/kg bwBasis:actual ingested

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Parental animals: Observations and examinations:

CAGE SIDE/CLINICAL OBSERVATIONS: Yes - Time schedule: daily two mortality checks five hours apart, once daily for external signs of toxicity- Cage side observations checked in table were included (Appendix III of the study report).BODY WEIGHT and FOOD CONSUMPTION: Yes - Time schedule for examinations: measured prior to initiation of the study (day -1), weekly thereafter, and at the time of necropsy. - Food consumption: measured weekly. - Food efficiency: Yes OPHTHALMOSCOPIC EXAMINATION: Yes - Time schedule for examinations: on all rats prior to initiation of the study and on all rats after 13 weeks of dosing. - The eyes of all rats were examined by indirect ophthalmoscopy after pupil dilation with 1% Tropica-mide. CLINICAL LABORATORY STUDIES: Yes- Blood samples for hematology and clinical chemistry determinations and urine samples for urine analysis were collected after 6 and 13 weeks of dosing from all animals.- Blood was drawn from the periorbi tal plexus (orbital sinus puncture) under light ether anesthesia. - Animals were fasted overnight prior to blood collection.* HAEMATOLOGY: Yes- Parameters: hemoglobin; hematocrit; erythrocyte count; total and differential leucocyte counts platelet count. * CLINICAL CHEMISTRY: Yes- Parameters: urea nitrogen; glutamic pyruvic transaminase (GPT) glutamic oxaloacetic transaminase (GOT) calcium; phosphorus; chloride; sodium; potassium; glucose; total bilirubin; albumin; globulin; total protein ; creatinine * URINALYSIS: Yes - Parameters: appearance; specific gravity; occult blood; protein; pH; bilirubin; urobilinogen; ketones; glucose; microscopic examination of sediment

Oestrous cyclicity (parental animals):

Not examined

Sperm parameters (parental animals):

Not examined

Litter observations:

Not applicable

Postmortem examinations (parental animals):

SACRIFICE- Male animals: All surviving animals - Maternal animals: All surviving animals GROSS NECROPSY- Gross necropsy HISTOPATHOLOGY / ORGAN WEIGHTS- Microscopic examination of paraffin embedded hema-toxylin and eosin stained tissue sections (3-5 microns) was performed on the following organs and tissues from all rats in the high dosage and control groups which were sacrificed at termination and from one rat that died during the course of the study: ovaries testes thyroid (both lobes) and parathyroidsadrenal glands liver spleen aorta stomach uterus cerebellular cortexpancreas thymus esophagus pituitary gland brain-medulla/pons heart rectum urinary bladder intestine, small (duodenum, jejunum, ileum) salivary gland (submaxillary) intestine, large (cecum, colon) sciatic nerve all gross lesionkidneys lung with mainstem bronchi lymph node (mesenteric)

Postmortem examinations (offspring):

Not applicable

Statistics:

Continuous data (body weight, food consumption, clinical parameters, absolute and relative organ weights) were analyzed using analysis of variance (Snedecor and Cochran, 1967). Differences between groups were identified using the Least Significant Difference test. Pathology inci- dence data were analyzed using Fisher's Exact test. For all statistical analyses, significance was juagea at the level of pi 0.05.

Reproductive indices:

Not applicable

Offspring viability indices:

Not applicable

Clinical signs:

no effects observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Other effects:

not specified

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

not examined

Dose descriptor:

NOAEL

Effect level:

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

Based on:

act. ingr.

Sex:

male/female

Basis for effect level:

other: overall effects: clinical signs; mortality; body weight; food consumption; food efficiency; ophthalmoscopic examination; haematology; clinical chemistry; urinalysis; gross pathology; organ weights; histopathology

Remarks on result:

other: Generation: juvenile to adult in a 90-day study (migrated information)

Clinical signs:

not examined

Reproductive function: oestrous cycle:

not examined

Remarks on result:

not measured/tested

Clinical signs:

not examined

Mortality / viability:

not examined

Body weight and weight changes:

not examined

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

not examined

Histopathological findings:

not examined

Remarks on result:

not measured/tested

Remarks on result:

not measured/tested

Reproductive effects observed:

not specified

Conclusions:

Oral administration (via gavage) of Suttocide A for 90 consecutive days to Sprague-Dawley rats at levels of 10, 40 and 160 mg/kg body weight did not result in any significant toxicological or histopathological effects which were treatment related. This includes examination of both testes and uteri of exposed male and female rats, respectively.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

160 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

Weight of evidence.

Additional information

Oral administration (via gavage) of Suttocide A for 90 consecutive days to Sprague-Dawley rats at levels of 10, 40 and 160 mg/kg body weight did not result in any significant toxicological or histopathological effects which were treatment related. This includes examination of both testes and uteri of exposed male and female rats, respectively.

Justification for selection of Effect on fertility via oral route:
The study consisted of ral administration (via gavage) of Suttocide A for 90 consecutive days to Sprague-Dawley rats at levels of 10, 40 and 160 mg/kg body weight and included histopathological examination of both testes and uteri of exposed male and female rats, respectively.

Effects on developmental toxicity

Link to relevant study records

Reference

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

June 19, 1990 through July 12, 1990 (in life)/ July 9, 1990 through July 12, 1990 (Cesarean Section)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study.

Qualifier:

according to guideline

Guideline:

EPA OPP 83-3 (Prenatal Developmental Toxicity Study)

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Details on test animals or test system and environmental conditions:

TEST ANIMALS- Source: Charles River Laboratories, Inc., Wilmington, Massachusetts - Age at study initiation: 101 days- Weight at study initiation: 238-296 grams- Fasting period before study: Not applicable- Housing: Rats were housed individually in stainless steel!" wire mesh cages sized in accordance with the "Guide for the Care and Use of Laboratory Animals" of the Institute of Laboratory Animal Resources, National Research Council. Nesting materials were not provided as sacrifice was scheduled prior to anticipated parturition. - Diet: Purina Certified Rodent Chow, Lot #0222901A, ad libitum. Feeders were designed to reduce soiling, bridging, and scattering. - Water: fresh tap water, ad libitum- Sanitization: Waste material was removed twice weekly. Cages and feeders were sanitized every two weeks. - Acclimation period: The rats were acclimated for eleven days. During this conditioning period the rats were weighed and observed for any clinical signs of disease or inadequate weight gain. All rats with any evidence of disease or physical abnormalities were discarded.ENVIRONMENTAL CONDITIONSLight cycle - 12 hours light, 12 hours dark. Temperature/Humidity - Every attempt was made to maintain a temperature of 22° C ± 3°C (66 °F to 77° F), and a hmnidity of 30 to 70%. :

Route of administration:

oral: gavage

Vehicle:

water

Remarks:

Deionized

Details on exposure:

The test article was prepared daily in the vehicle to obtain 5% w/v active aqueous solution. Human exposure is unlikely by the oral route. However, the oral route was chosen to maximize systemic exposure to the test article.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Samples of the test article vehicle mixtures and vehicle control were submitted to sponsor on June 25, 1990 (Day 6) and July 5, 1990 (Day 15).

Details on mating procedure:

Animals from respective groups were mated by placing one male and one or two females, selected at random in a breeding cage until females exhibited evidence of copulation. These females were then assigned to respective groups consecutively. Vaginal examinations and slides were made daily to determine if sperm were present. The day of observation of a vaginal plug and sperm or only sperm was designated as Day O of gestation.

Duration of treatment / exposure:

Once daily beginning after implantation (Day 6 of gestation) and continuing through gestation to Day 15 of pregnancy with Day 0 defined as the day a vaginal plug and/or sperm were found. Concurrently, another group of mated females received deionized water at a dose volume of 9 ml/kg/day and served as the vehicle control.

Frequency of treatment:

once daily

Duration of test:

20 days

Dose / conc.:

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

Dose / conc.:

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

Dose / conc.:

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

Dose / conc.:

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

No. of animals per sex per dose:

27 mated female Sprague Dawley rats to produce at least 20 litters per dose group.

Control animals:

yes, concurrent vehicle

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes - Time schedule: Throughout the test period, each animal was observed at least once daily- Cage side observations were included. Pertinent changes and signs of toxicity including mortality were recorded. BODY WEIGHT: Yes- Time schedule for examinations: The females were weighed the day copulation was confirmed (Day 0) and on Days 6, 9, 12, 15 and 20 of presumed gestation. The amount of test material administered to the individual females during the dosing period was based on the most recent body weights.FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes Food consumption was recorded for gestation Days 0-6, 6-9, 9-12, 12-15 and 15-20.WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): NoPOST-MORTEM EXAMINATIONS: Yes - Sacrifice on day 20- both actual and corrected body weights (subtract weight of gravid uterus) were recorded.- Necropsy was performed and the carcass discarded. All fetuses were individually weighed, sexed, numbered, tagged and examined for external malformations and variations.

Ovaries and uterine content:

The number and location of viable and non-viable fetuses, early and late resorptions, total implantations and corpora lutea were recorded on the log form for the individual dam.

Fetal examinations:

Approximately one-half of the fetuses were placed in Bouin's fluid for subsequent soft tissue examination by free-hand sectioning. The remaining fetuses were placed in ethyl alcohol (95%), later macerated with potassium hydroxide and stained with Alizarin Red S (Lot #126F-0315) for subsequent skeletal examination. Fetal alterations were classified as malformations or developmental variations.

Statistics:

Statistical analyses compared the treatment groups to the control group with the level of significance at p< 0.05 . Only gravid females were used in statistical analyses. Maternal body weight, body weight gain, food consmnption and the mean number of viable fetuses, non-viable fetuses, total implantations and corpora lutea were compared by analysis of variance (one-way classification), to judge significance of differences from the respective control mean. Non-parametric statistics were used where variances were significantly different between groups as per Bartlett's Test. The number of early resorptions, late resorptions, pre- and post-implantational losses and percentages of these resorptions and losses were compared by the Mann-Whitney U-Test to judge significance of differences. The male and female fetal sex distribution and the number of litters with malformations were compared using Chi-Square test. Statistics were calculated using Systat by Systat Inc., Evanston, IL (Pharmakon S.O.P. PH-083).

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

Six dams in the 150 mg/kg/day dose group exhibited post-dose salivation. The majority of the dams in the 300 and 450 mg/kg/day dose groups exhibited post-dose salivation. Additional signs noted in these dose groups included chromodacryorrhea, decreased activity, poor grooming, abnormal stance, abnormal gait and decreased body tone. These deaths were attributed to technical error (pulmonary intubation) and not the result of test article toxicity.

Mortality:

mortality observed, non-treatment-related

Description (incidence):

Two dams from the 150 mg/kg/day dose group died during the study. Necropsy revealed hydrothorax, dark red lungs, ascities and air filled red discolored intestines.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

450 mg/kg/day dose group: suppressed body weight gain but not statistically significant.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

450 mg/kg/day dose group: statistically significant reduced food consumption

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Number of abortions:

no effects observed

Description (incidence and severity):

No statistically significant differences were observed in the mean number of corpora lutea, implantations, viable fetuses, non-viable fetuses, late resorptions, early resorptions, fetal body weight, fetal sex distribution, or the number and percentage of pre- or post-implantation losses.

Pre- and post-implantation loss:

no effects observed

Total litter losses by resorption:

no effects observed

Early or late resorptions:

no effects observed

Dead fetuses:

no effects observed

Changes in pregnancy duration:

not examined

Description (incidence and severity):

Migrated Data from removed field(s)
Field "Effects on pregnancy duration" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsMaternalAnimals.MaternalDevelopmentalToxicity.EffectsOnPregnancyDuration): no effects observed

Changes in number of pregnant:

not specified

Other effects:

not specified

Details on maternal toxic effects:

Maternal toxic effects:yesDetails on maternal toxic effects:Maternal toxicity was observed in the 450 mg/kg/day dose group as evidence by suppressed body weight gain and reduced food consumption. All dams in the high dose group exhibited either decreased activity, post dose salivation or both.

Dose descriptor:

NOEL

Effect level:

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

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

Fetal body weight changes:

no effects observed

Description (incidence and severity):

Migrated Data from removed field(s)
Field "Fetal/pup body weight changes" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsFetuses.FetalPupBodyWeightChanges): not specified

Reduction in number of live offspring:

no effects observed

Description (incidence and severity):

There was one fetal death observed at cesarean section from the 300 mg/kg/day (mid dose) dose group. Necropsy revealed pale placenta, maceration, edema and lack of bone ossification. This death was judged coincidental and not related to treatment with the test article.

Changes in sex ratio:

no effects observed

Changes in litter size and weights:

not specified

Changes in postnatal survival:

no effects observed

External malformations:

no effects observed

Skeletal malformations:

effects observed, non-treatment-related

Description (incidence and severity):

Eight fetuses with skeletal malformations were detected during the study: seven low dose fetuses (2.1%) from one litter (4.2%) and one high dose fetus (0.3%) from one litter (3.8%). The first seven exhibited abnormally shaped scapula (broad and flat) and short appendicular bones (humerus, radius, ulna, femur, tibia and fibula). While this produced statistical significance in the total number of skeletal malformations in this low dose group compared to controls, litter incidence was not statistically significant. The one fetus from the high dose group exhibited unaligned vertebrae. All eight skeletal malformations were not observed dose dependent, were inconsistant in type and incidence and are considered spontaneous and not related to treatment with Suttocide A.

Visceral malformations:

no effects observed

Other effects:

no effects observed

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

reduction in number of live offspring

changes in sex ratio

changes in litter size and weights

changes in postnatal survival

external malformations

skeletal malformations

visceral malformations

Abnormalities:

not specified

Developmental effects observed:

not specified

Conclusions:

Based upon this study, the no-observed effect level for maternal toxicity is 300 mg/kg/day and the no-observed effect level for developmental toxicity is 450 mg/kg/day. Suttocide A, Lot #PLI-40 did not exhibit selective toxicity toward the developing conceptus.

Executive summary:

One hundred and eight female Sprague Dawley rats were mated for use in a study to determine the potential of Suttocide A, Lot #PLI-4D, to produce or alter the incidence of congenital malformations in offspring of pregnant female rats pretreated with the test article. The test article was administered orally by gavage, at doses of 150, 300 and 450 mg/kg/day from Day 6 through Day 15 of gestation. Two dams from the 150 mg/kg/day dose group died during the study. Each death was attributed to technical error and not the result of test article toxicity. All other dams survived the duration of the study. All dams in the high dose group exhibited either decreased activity, post-dose salivation or both. Post-dose salivation was also observed in females exposed to the mid-dose group. Although not statistically significant, the females in the 450 mg/kg/day dose group gained only 69% of control body weight (i.e. 31% reduction) during the Days 6 through 15 dosing interval. A significant decrease was also observed in the amount of feed consumed for the 450 mg/kg/day dose group during Days 6 through 9 and 9 through 12 of gestation. Therefore, maternal toxicity was observed in the 450 mg/kg/day dose group as evidence by suppressed body weight gain and reduced food consumption.

Based upon the number of gravid animals per group, there were no statistically significant differences in the total number of implantation sites, viable fetuses, non-viable fetuses, early resorptions, late resorptions, fetal sex distribution, fetal body weights, corpora lutea, the number and percentage of pre-implantation or post-implantation losses. There were no soft tissue malformations detected in the study but eight fetal skeletal malformations were present. Seven occured in one litter of the low dose and one occurred in one litter of the high dose group. However, each malformation was considered spontaneous. A variety of spontaneous developmental variations were also observed in the control and Suttocide A treated groups. There were no significant differences observed in the number of fetuses exhibiting these variations.

Based upon these findings the no-observed effect level for maternal toxicity is 300 mg/kg/day and the no-observed effect level for developmental toxicity is 450 mg/kg/day. Suttocide A, Lot #PLI-40 did not exhibit selective toxicity toward the developing conceptus.

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

450 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

One hundred and eight female Sprague Dawley rats were mated for use in a study to determine the potential of Suttocide A, Lot #PLI-4D, to produce or alter the incidence of congenital malformations in offspring of pregnant female rats pretreated with the test article. The test article was administered orally by gavage, at doses of 150, 300 and 450 mg/kg/day from Day 6 through Day 15 of gestation. Two dams from the 150 mg/kg/day dose group died during the study. Each death was attributed to technical error and not the result of test article toxicity. All other dams survived the duration of the study. All dams in the high dose group exhibited either decreased activity, post-dose salivation or both. Post-dose salivation was also observed in females exposed to the mid-dose group. Although not statistically significant, the females in the 450 mg/kg/day dose group gained only 69% of control body weight (i.e. 31% reduction) during the Days 6 through 15 dosing interval. A significant decrease was also observed in the amount of feed consumed for the 450 mg/kg/day dose group during Days 6 through 9 and 9 through 12 of gestation. Therefore, maternal toxicity was observed in the 450 mg/kg/day dose group as evidence by suppressed body weight gain and reduced food consumption.

Based upon the number of gravid animals per group, there were no statistically significant differences in the total number of implantation sites, viable fetuses, non-viable fetuses, early resorptions, late resorptions, fetal sex distribution, fetal body weights, corpora lutea, the number and percentage of pre-implantation or post-implantation losses. There were no soft tissue malformations detected in the study but eight fetal skeletal malformations were present. Seven occured in one litter of the low dose and one occurred in one litter of the high dose group. However, each malformation was considered spontaneous. A variety of spontaneous developmental variations were also observed in the control and Suttocide A treated groups. There were no significant differences observed in the number of fetuses exhibiting these variations.

Based upon these findings the no-observed effect level for maternal toxicity is 300 mg/kg/day and the no-observed effect level for developmental toxicity is 450 mg/kg/day. Suttocide A, Lot #PLI-40 did not exhibit selective toxicity toward the developing conceptus.

Justification for selection of Effect on developmental toxicity: via oral route:
GLP study according to an internationally accepted guideline.

Justification for classification or non-classification

Since the no-effect level for sub-chronic exposure on tissue of testes and uteri was 160 mg/kg bw/day and the no-effect level for

teratogenic effects is above the no-effect level for maternal toxicity, the substance does not comply with criteria for classification as reprotoxic or teratogenic.