Diisotridecyl phosphonate

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Remarks:

combined repeated dose and reproduction / developmental screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

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

Deviations:

yes

Remarks:

This protocol exceeded the OECD 422 study design by following the F1 offspring to adulthood, with continued exposure and assessments of neurologic, immunologic and reproductive structures and functions. The protocol also assessed F0 recovery males, 28-day

Principles of method if other than guideline:

Method: Modified

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Triisodecyl phosphite

EC Number:

246-998-3

EC Name:

Triisodecyl phosphite

Cas Number:

25448-25-3

IUPAC Name:

tris(8-methylnonyl) phosphite

Details on test material:

- Name of test material (as cited in study report): TDP
- Analytical purity: > 99%
- Lot/batch No.: Doverphos 6, Batch 162T041801

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

Male and female CD (Sprague-Dawley(SD)) F0 rats were administered TDP orally by gavage at 0, 50, 250 and 1000 mg/kg/day at a dose volume of 5 ml/kg/day in Mazola® corn oil, 10 animals/sex/dose, for 2 weeks of prebreed exposure (males and females), 2 weeks of mating (males and females) and 3 weeks of gestation and lactation each (F0 females).

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Homogeneity and stability studies were run on TDP in corn oil at concentrations of 10, 50, and 200 mg/mL (TDP in corn oil). The 50 and 200 mg/mL concentrations were prepared weekly as they were found to be stable. The 10 mg/mL concentration was prepared daily due to stability concerns.

Duration of treatment / exposure:

8 weeks

Frequency of treatment:

once per day

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 50, 250 and 1000 mg/kg/day
Basis:
actual ingested

No. of animals per sex per dose:

10

Control animals:

yes

Details on study design:

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: at least once daily for F0 males and females until necropsy.

BODY WEIGHT: Yes
- Time schedule for examinations: F0 males and females weekly during the prebreed period for both sexes and for F0 females during gestation and lactation.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes
- F0 males and females weekly during the prebreed period for both sexes and for F0 females during gestation and lactation.

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food efficiency:

no effects observed

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

no effects observed

Behaviour (functional findings):

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Effect levels

Key result

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

TDP administered by gavage once daily at 0, 50, 250 and 1000 mg/kg/day to parental F0 CD (SD) rats, 10/sex/group through prebreed, mating, gestation and F1 lactation resulted in essentially no treatment or dose related adult F0 parental toxicity at any dose at any time. Reproductive toxicity was not present in F0 males or females. There was also no F1offspring toxicity observed postnatally through the weanling necropsy. Therefore, the F0 male and female systemic no observable adverse effect level (NOAEL) was at or above 1000mg/kg/day for males and females. The NOAELs for F0 reproductive toxicity were observed at or above 1000 mg/kg/day for males and females. The NOAELs for F1 offspring toxicity during lactation were also at or above 1000 mg/kg/day for males and females. (Author)

Executive summary:

TDP administered by gavage once daily at 0, 50, 250 and 1000 mg/kg/day to parental F0 CD (SD) rats, 10/sex/group through prebreed, mating, gestation and F1 lactation resulted in essentially no treatment or dose related adult F0 parental toxicity at any dose at any time. Reproductive toxicity was not present in F0 males or females. There was also no F1offspring toxicity observed postnatally through the weanling necropsy. Therefore, the F0 male and female systemic no observable adverse effect level (NOAEL) was at or above 1000mg/kg/day for males and females. The NOAELs for F0 reproductive toxicity were observed at or above 1000 mg/kg/day for males and females. The NOAELs for F1 offspring toxicity during lactation were also at or above 1000 mg/kg/day for males and females.