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Toxicological information

Developmental toxicity / teratogenicity

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Administrative data

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Study period:
22 September 2009 -10 November 2009
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
This study was conducted in accordance with international guidelines in a GLP laboratory. All relevant validity criteria were met.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report Date:
2010

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)
Deviations:
no
GLP compliance:
yes
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Hexahydro-1,3,5-Trimethyl-S-Triazine- Substance type: Clear pale yellow liquid- Physical state: liquid- Stability under test conditions: Stable- Storage condition of test material: At room temperature in the dark

Test animals

Species:
rat
Strain:
other: Rat: Crl:WI(Han) (outbred, SPF-Quality).
Details on test animals and environmental conditions:
TEST ANIMALS- Source: Charles River Deutschland, Sulzfeld, Germany- Age at study initiation: Approximately 9-10 weeks- Fasting period before study: no- Housing: Pre-matingAnimals were housed in groups of 5 animals/sex/cage in Macrolon cages (MIV type, height 18 cm).MatingFemales were caged together with males on a one-to-one-basis in Macrolon cages (MIII type, height 18 cm).Post-matingMales were housed in their home cage (Macrolon cages, MIV type, height 18 cm) with a maximum of 5 animals/cage. Females were individually housed in Macrolon cages (MIII type, height 18 cm).LactationPups were kept with the dam until termination in Macrolon cages (MIII type, height 18 cm).GeneralSterilised sawdust as bedding material (Litalabo, S.P.P.S., Argenteuil, France) and paper as cage-enrichment (Enviro-dri, Wm. Lillico & Son (Wonham Mill Ltd), Surrey, United Kingdom) were supplied. Certificates of analysis were examined and then retained in the NOTOX archives. During activity monitoring, animals were housed individually in Macrolon cages (MIII type; height 15 cm) with sterilised sawdust as bedding material. No cageenrichment was provided during activity monitoring.- Diet (e.g. ad libitum): Free access to pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany). - Water (e.g. ad libitum): Free access to tap-water. - Acclimation period: At least 5 days prior to start of treatment.ENVIRONMENTAL CONDITIONS- Temperature (°C): 21 ± 3°C (actual range: 20.2 – 21.9°C)- Humidity (%): 40 - 70% (actual range: 28 - 76%) - Air changes (per hr): 15- Photoperiod (hrs dark / hrs light): 12/12IN-LIFE DATES: From: 22 September 2009 (allocation) To: 10 November 2009 (end of in-life phase)

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
propylene glycol
Details on exposure:
PREPARATION OF DOSING SOLUTIONS:Formulations (w/w) were prepared daily within 6 hours prior to dosing and were homogenised to a visually acceptable level. Adjustment was made for the density of the test substance (1.0202), the specific gravity of the vehicle (1.036) and the water content (66.44%).VEHICLE- Justification for use and choice of vehicle (if other than water): Based on trial formulations performed at NOTOX.- Concentration in vehicle: 2, 6 and 29 mg/mL (expressed as mas neat mg Hexahydro-1,3,5-Trimethyl-1,3,5-Triazine/kg b.w.- Amount of vehicle (if gavage): 5 mL/kg body weight. Actual dose volumes were calculated according to the latest body weight.
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Analyses were conducted on two occasions during the treatment phase (28 September and 08 October 2009), according to a validated method (NOTOX project 492054). Samples of formulations were analyzed for homogeneity (highest and lowest concentration) and accuracy of preparation (all concentrations). Stability in vehicle over 6 hours at room temperature was also determined (highest and lowest concentration).The accuracy of preparation was considered acceptable if the mean measured concentrations were 90-110% of the target concentration. Homogeneity was demonstrated if the coefficient of variation was ≤ 10%. Formulations were considered stable if the relative difference before and after storage was maximally 10%.
Details on mating procedure:
- M/F ratio per cage: 1/1- Length of cohabitation: A maximum of 13 days was allowed for mating.- Proof of pregnancy: sperm in the vaginal lavage or by the appearance of an intravaginal copulatory plug referred to as day 0 of pregnancy- Further matings after two unsuccessful attempts: no- After successful mating each pregnant female was caged (how): individually- Any other deviations from standard protocol: no
Duration of treatment / exposure:
Males were exposed for 28 days, i.e. 2 weeks prior to mating, during mating, and up to termination. Females were exposed for 41-48 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:
Once daily
Doses / concentrationsopen allclose all
Dose / conc.:
10 mg/kg bw/day (actual dose received)
Dose / conc.:
30 mg/kg bw/day (actual dose received)
Dose / conc.:
100 mg/kg bw/day (actual dose received)
No. of animals per sex per dose:
10
Control animals:
yes, concurrent vehicle
Details on study design:
- Dose selection rationale: Dose levels were based on results of the dose range finding study (NOTOX Project 491831)

Examinations

Maternal examinations:
Parental animals: Observations and examinationsCAGE SIDE OBSERVATIONS: Yes - Time schedule: At least twice daily (early morning/late afternoon)DETAILED CLINICAL OBSERVATIONS: Yes - Time schedule: At least once daily, detailed clinical observations were made in all animals. Once prior to start of treatment and at weekly intervals this was also performed outside the home cage in a standard arena. Arena observations were not performed when the animals were mating, or housed individually.BODY WEIGHT: Yes- Time schedule for examinations: Males and females were weighed on the first day of exposure and weekly thereafter. Mated females were weighed on Days 0, 4, 7, 11, 14, 17 and 20 post-coitum, and during lactation on Days 1 and 4. FOOD CONSUMPTION: YesWeekly, for males and females. Food consumption was not recorded during the mating period. Food consumption of mated females was measured on Days 0, 4, 7, 11, 14, 17 and 20 post-coitum and during lactation on Days 1 and 4.WATER CONSUMPTION: No, Subjective appraisal was maintained during the study, but no quantitative investigation introduced as no effect was suspected.HAEMATOLOGY: Yes - Time schedule for collection of blood: immediately prior to scheduled post mortem examination, between 7.00 and 10.30 a.m. - Anaesthetic used for blood collection: Yes iso-flurane- Animals fasted: yes, but water was available - How many animals: 5 males/group (random) and all females with live pups- Parameters examined were: white blood cells, differential leucocyte count (neutrophils, lymphocytes, monocytes, eosinophils, basophils), red blood cells, reticulocytes, red blood cell distribution width, haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, platelets, prothrombin time, activated Partial thromboplastin time.CLINICAL CHEMISTRY: Yes - Time schedule for collection of blood: immediately prior to scheduled post mortem examination, between 7.00 and 10.30 a.m. - Animals fasted: yes, but water available- How many animals: 5 males/group (random) and all females with live pups- Parameters examined were: Alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total protein, albumin, total bilirubin, urea, creatinine, glucose, cholesterol, sodium, potassium, chloride, calcium, inorganic phosphate, bile acids.URINALYSIS: NoNEUROBEHAVIOURAL EXAMINATION: Yes - Time schedule for examinations: The selected males were tested during Week 4 of treatment and the selected females were tested during lactation (all before blood sampling). - Dose groups that were examined: all- Battery of functions tested: hearing ability, pupillary reflex, static righting reflex, grip strength and motor activity Estrous cyclicity (Parental animals)not determined (not required)Sperm parameters (Parental animals)Parameters examined in all male parental animals:testis weight, epididymis weight.in addition, for 5 males of the control and high dose group, slides of the testes were prepared to examine staging of spermatogenesis. Postmortem examinations (Parental animals)SACRIFICE- Male animals: All surviving animals following completion of the mating period (a minimum of 28 days of dose administration).- Maternal animals: All surviving animals on lactation Days 5-6.- Females which failed to deliver: Post-coitum Day 27 (evidence of mating) or 22 days after the last day of the mating period (without evidence of mating).GROSS NECROPSYAll animals were subjected to macroscopic examination of the cranial, thoracic and abdominal tissues and organs, with special attention being paid to the reproductive organs. The number of former implantation sites and corpora lutea was recorded for all paired females.From all animals, samples of the following tissues and organs were collected and fixed in 10% buffered formalin (neutral phosphate buffered 4% formaldehyde solution, Klinipath, Duiven, The Netherlands):Identification marks (not processed), Cervix, Clitoral gland, Epididymides*, Ovaries, Preputial gland, Prostate gland, Seminal vesicles including coagulating gland, Testes*, Uterus, Vagina, All gross lesions.From 5 males/group (random) and all females with live pups, samples of the following tissues and organs were collected and fixed in addition to the abovementioned list:Adrenal glands, Aorta, Brain (cerebellum, mid-brain, cortex), Caecum, Colon, Duodenum, Eyes (including optic nerve and Harderian gland)*, Female mammary gland area, Femur including joint, Heart, Ileum, Jejunum, Kidneys, Lacrimal gland (exorbital), Larynx, Liver, Lung (infused with formalin), Lymph nodes (mandibular, mesenteric), Nasopharynx, Oesophagus, Pancreas, Peyer's patches (jejunum, ileum) if detectable, Pituitary gland, Rectum, Salivary glands (mandibular, sublingual), Sciatic nerve, Skeletal muscle, Skin, Spinal cord (cervical, midthoracic, lumbar), Spleen, Sternum with bone marrow, Stomach, Thymus, Thyroid including parathyroid (if detectable), Tongue, Trachea, Urinary bladder.*Fixed in modified Davidson's solution and transferred to formalin after fixation for at least 24 hours.ORGAN WEIGHTS: YesThe following organ weights and terminal body weight were recorded from 5 males/group (random) and all females with live pups on the scheduled day of necropsy:Adrenal glands, Brain, Epididymides (all males), Heart, Kidneys, Liver, Ovaries Spleen, Testes (all males), Thymus, Uterus (including cervix), Prostate*, Seminal vesicles including coagulating glands*, Thyroid including parathyroid** weighed when fixed for at least 24 hours.HISTOPATHOLOGY: Yes The following slides were examined by a pathologist:- The preserved organs and tissues of 5 selected animals/sex of Groups 1 and 4.- The additional slides of the testes of the selected 5 males of Groups 1 and 4 to examine staging of spermatogenesis.- All gross lesions of all animals (all dose groups).- The reproductive organs (cervix, clitoral gland, coagulation gland, epididymides, ovaries, preputial gland, prostate gland, seminal vesicles, testis, uterus, and vagina) of all animals that failed to mate, conceive, sire or deliver healthy pups.
Fetal examinations:
Litter observationsPARAMETERS EXAMINEDThe following parameters were examined in F1 offspring:number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross abnomalies, weight gain, physical or behavioural abnormalities.GROSS EXAMINATION OF DEAD PUPS: YesIf possible, defects or cause of death were evaluated.Postmortem examinations (Offspring)SACRIFICEPups surviving to planned termination were killed by decapitation on lactation Days 5-6.GROSS NECROPSYAll 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. Any abnormal pup, organ or tissue was preserved in 10% buffered formalin for possible further examination.HISTOPATHOLOGY / ORGAN WEIGTHSno
Statistics:
Reproductive indicesFor each group, the following calculations were performed:Percentage mated females: Number of females mated/Number of females paired x 100Fertility index: Number of pregnant females/Number of females paired x 100Conception index: Number of pregnant females/Number of females mated x 100Gestation index: Number of females bearing live pups/Number of pregnant females x 100Duration of gestation: Number of days between confirmation of mating and the beginning of parturitionFor each group, the following calculations were performed:Percentage mated females: Number of females mated/Number of females paired x 100Fertility index: Number of pregnant females/Number of females paired x 100Conception index: Number of pregnant females/Number of females mated x 100Gestation index: Number of females bearing live pups/Number of pregnant females x 100Duration of gestation: Number of days between confirmation of mating and the beginning of parturitionOffspring viability indicesPercentage live males at First Litter Check: Number of live male pups at First Litter Check/Number of live pups at First Litter Check x 100Percentage live females at First Litter Check: Number of live female pups at First Litter Check/Number of live pups at First Litter Check x 100Percentage of postnatal loss Days 0-4 of lactation: Number of dead pups on Day 4 of lactation/Number of live pups at First Litter Checkx 100Number of live pups at First Litter Check Viability index (%) Number of live pups on Day 4 of lactation x 100Number of pups born alive

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:
effects observed, treatment-related
Description (incidence and severity):
At 100 mg/kg bw/d, salivation was noted for all animals from week 4 of treatment onwards. Rales (slight to moderate) were noted for two males and one female treated at 100 mg/kg bw/d for 2, 5 or 12 days. The male (no. 40) that showed rales for 12 days, also showed piloerection for 2 days.Rales (slight) were also noted for one male treated at 10 mg/kg bw/d for 2 days and one female treated at 30 mg/kg bw/d for 2 days. At this low incidence, these observations were not considered toxicologically significant.Alopecia was noted for three females. The finding occurred wthin the range of background findings to be expected for rats of this age and strain whcih are housed and treated under the conditions of the study.
Mortality:
mortality observed, non-treatment-related
Description (incidence):
One male at 100 mg/kg bw/d (no.33) died on the scheduled day of necropsy during the anaesthesia procedure before blood sampling. No cause of death could be established, but was however not considered treatment related.
Body weight and weight changes:
no effects observed
Food consumption and compound intake (if feeding study):
not specified
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
effects observed, treatment-related
Description (incidence and severity):
Eyes (females): Degeneration of the retina (atrophy) was recorded in 3/5 females (minimal-sight)
Haematological findings:
effects observed, non-treatment-related
Description (incidence and severity):
Minor statistically significant decreases arising between controls and animals receiving 100 mg/kg bw/d (decreased haemoglobin and decreased APTT for males and increased APTT for females) were considered not to represent a change of biological significance as the changes were slight and the values remained within the range considered normal for rats of this age and strain.Individual increases of neutrophil counts with concurrently reduced lymphocyte counts was noted for one male (no. 3) of the control group. This shift in type of white blood cells was considered to be a secondary non-specific response to stress and to be of no toxicological significance.
Clinical biochemistry findings:
effects observed, non-treatment-related
Description (incidence and severity):
At 100 mg/kg bw/d, total protein and albumin were slightly decreased for both sexes.Any statistically significant changes at 30 mg/kg bw/d (bile acids for males) and at 100 mg/kg bw/d (chloride for males) were considered to be of no toxicological significance as they occurred in the absence of a treatment-related distribution or remained within the range considered normal for rats of this age and strain.The increased values for bile acids (not statistically significant), noted for females of all dose groups were considered to have occured by chance and to be of no toxicological relevance as these changes were caused by individual animals only.
Urinalysis findings:
not examined
Behaviour (functional findings):
no effects observed
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
no effects observed
Gross pathological findings:
effects observed, non-treatment-related
Description (incidence and severity):
At 100 mg/kg bw/d, five males and eight females showed a thickened limiting ridge of the stomach.This finding was also noted for one female treated at 30 mg/kg bw/d. However, at this singlr occurrence and without microscopic correlate it was not considered to be toxicologically significant.For the male at 100 mg/kg bw/d (no.33) that dies on the day of scheduled necropsy, incomplete exsanguination was noted. One female (no. 42) of the control group showed one dead fetus in the right uterus horn. Other incidental findings are not summarised. The incidenced of all gross pathological findings were within the background range of findings that are encountered among rats of this age and strain, and did not show a dose-related incidence. All necropsy findings were considered to be of no toxicological significance.
Neuropathological findings:
no effects observed
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Description (incidence and severity):
Stomach: Lymphogranulocytic inflammation of the glandular stomach (minimal) was recorded in 5/5 males and 4/8 females. Hyperplasia of the epithelium of the limiting ridge was recorded in 2/5 males (minimal) and 6/8 females (minimal-slight). This was in most cases the microscopic correlate to the thickening of the limiting ridge recorded at necropsy.
Histopathological findings: neoplastic:
no effects observed
Other effects:
no effects observed

Maternal developmental toxicity

Number of abortions:
no effects observed
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:
no effects observed
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:
no effects observed
Other effects:
no effects observed

Effect levels (maternal animals)

Key result
Dose descriptor:
NOAEL
Effect level:
ca. 30 mg/kg bw/day (actual dose received)
Based on:
test mat.
Basis for effect level:
other: other:

Results (fetuses)

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): no effects observed
Reduction in number of live offspring:
no effects observed
Changes in sex ratio:
not specified
Changes in litter size and weights:
not specified
Changes in postnatal survival:
no effects observed
External malformations:
no effects observed
Skeletal malformations:
no effects observed
Visceral malformations:
no effects observed
Other effects:
no effects observed

Effect levels (fetuses)

Dose descriptor:
NOAEL
Effect level:
>= 100 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: No reproductive/developmental toxicity was observed at any dose level

Fetal abnormalities

Abnormalities:
not specified

Overall developmental toxicity

Developmental effects observed:
not specified

Any other information on results incl. tables

Results of examinations: parental animals

Clinical signs (parental animals)

yes

Body weight and food consumption (parental animals)

no effects

Test substance intake (parental animals)

not examined

Reproductive function: estrous cycle (parental animals)

no effects

Reproductive function: sperm measures (parental animals)

no effects

Reproductive performance (parental animals)

no effects

Organ weights (parental animals)

no effects

Gross pathology (parental animals)

yes

Histopathology (parental animals)

yes

Details on results (parental animals)

CLINICAL SIGNS AND MORTALITY: No mortality occurred during the study period that was considered to be related to treatment with the test substance. One male at 100 mg/kg/day died on the scheduled day of necropsy during the anaesthesia procedure before blood sampling. No cause of death could be established, but was however not considered treatment related. At 100 mg/kg body weight/day, salivation was noted for all animals from Week 4 of treatment onwards. Rales (slight to moderate) were noted for two males and one female treated at 100 mg/kg for 2, 5 or 12 days. The male that showed rales for 12 days, also showed piloerection for 2 days. Rales (slight) were also noted for one male treated at 10 mg/kg for 2 days and one female treated at 30 mg/kg for 2 days. At this low incidence, these observations were not considered toxicologically significant. Alopecia was noted for three females. This finding occurred within the range of background findings to be expected for rats of this age and strain which are housed and treated under the conditions in this study.

BODY WEIGHT AND WEIGHT GAIN Mean body weights and body weight gain of treated animals remained in the same range as controls over the treatment period.

FOOD CONSUMPTION Food consumption before or after allowance for body weight was similar between treated and control animals.

NEUROBEHAVIOUR: No toxicologically significant effects on hearing ability, pupillary reflex, static righting reflex and grip strength were observed. The variation in motor activity did not indicate a relation with treatment.

REPRODUCTIVE FUNCTION: SPERM MEASURES (PARENTAL ANIMALS) No toxicologically significant changes.

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS) No toxicologically significant effects on reproductive parameters were noted.

ORGAN WEIGHTS No toxicologically significant changes were noted in organ weights and organ to body weight ratios up to 100 mg/kg body weight/day. The statistical significant decreased values for testes and epididymides weights (absolute and relative) at the high dose group were not considered toxicologically significant as the changes were very slight, no corroborative findings were noted at microscopic examination, and reproduction was unaffected.

GROSS PATHOLOGY At 100 mg/kg, five males and eight females showed a thickened limiting ridge of the stomach. This finding was also noted for one female treated at 30 mg/kg body weight/day. However, at this single occurrence and without microscopic correlate it was not considered toxicologically significant. For the male at 100 mg/kg/day that died on the scheduled day of necropsy during the anaesthesia procedure before blood sampling, incomplete exsanguination was noted. One female of the control group showed one dead fetus in the right uterus horn. Other incidental findings included soft yellowish or greenish nodule at the epididymides, isolated reddish or dark red foci at the glandular mucosa of the stomach, reddish discolouration of the Peyers patches of the jejunum, reddish discolouration of the thymus or mandibular lymph nodes, exophthalmus of the left eye, red-brown foci at the preputial glands or clitoral glands, watery-clear cyst at the uterus or ovaries, greenish foci at the clitoral glands, alopecia, dark red foci at the thymus, and the uterus containing fluid. The incidence of these findings was within the background range of findings that are encountered among rats of this age and strain, and did not show a dose-related incidence trend. These necropsy findings were therefore considered to be of no toxicological significance.

HISTOPATHOLOGY: NON-NEOPLASTIC Treatment-related microscopic findings were present in stomach (males and females) and eyes (females) at 100 mg/kg:

- Stomach: Lymphogranulocytic inflammation of the glandular stomach (minimal) was recorded in 5/5 males and 4/8 females. Hyperplasia of the epithelium of the limiting ridge was recorded in 2/5 males (minimal) and 6/8 females (minimal-slight). This was in most cases the microscopic correlate to the thickening of the limiting ridge recorded at necropsy.

- Eyes (females): Degeneration of the retina (atrophy) was recorded in 3/5 females (minimal-slight). All remaining microscopic findings recorded were considered to be within the normal range of background pathology encountered in Wistar Han rats of this age and strain. No abnormalities were seen in the reproductive organs of all animals that failed to mate, conceive, sire or deliver healthy offspring which could account for infertility. The assessment of the integrity of the spermatogenetic cycle did not provide any evidence of impaired spermatogenesis.

Results of examinations: offspring

Viability (offspring)

no effects

Clinical signs (offspring)

no effects

Body weight (offspring)

no effects

Sexual maturation (offspring)

not examined

Organ weights (offspring)

not examined

Gross pathology (offspring)

no effects

Histopathology (offspring)

not examined

Details on results (offspring) No toxicologically significant effects on developmental parameters were observed. No deficiencies in maternal care were observed. Examination of cage debris of pregnant females revealed no signs of abortion or premature birth. No signs of difficult or prolonged parturition were noted among the pregnant females Gestation index, duration of gestation, number of dead and living pups at first litter check, sex ratio, postnatal loss, viability index, and early postnatal pup development (mortality, clinical signs, body weight and external macroscopy) were unaffected by treatment. One pup of Group 2 was found dead on Day 2 of lactation. This single occurrence was considered to have occurred by chance. Incidental clinical symptoms consisted of small size, blue spot on the neck, pale appearance and broken tail. Incidental macroscopic findings included small size and scab on the apex of the tail. No relationship with treatment was established for these observations and they were considered to be of no toxicological significance.

Applicant's summary and conclusion

Conclusions:
Treatment with Hexahydro-1,3,5-Trimethyl-S-Triazine by oral gavage in male and female Wistar Han rats at dose levels of 10, 30 and 100 mg/kg body weight/day revealed parental toxicity at 100 mg/kg body weight/day. No reproduction and developmental toxicity was observed for treatment up to 100 mg/kg body weight/day. Based on the results, the following No Observed Adverse Effect Levels (NOAEL) were derived:Parental NOAEL: 30 mg/kg/dayReproductive NOAEL: ≥100 mg/kg/dayDevelopmental NOAEL: ≥100 mg/kg/day