Methyl hydrogen octadecylphosphonate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March 31, 2004 - April 22, 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 425 (Acute Oral Toxicity: Up-and-Down Procedure)

Deviations:

yes

Remarks:

The dose preparations were not analysed to confirm test article concentration, stability or homogeneity. This deviation is not considered to adversely effect the outcome of this study

GLP compliance:

yes

Test type:

up-and-down procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Methyl hydrogen octadecylphosphonate

EC Number:

246-905-6

EC Name:

Methyl hydrogen octadecylphosphonate

Cas Number:

25371-55-5

Molecular formula:

C19H41O3P

IUPAC Name:

methoxy(octadecyl)phosphinic acid

impurity 1

Reference substance name:

Octadecylphosphonic acid

EC Number:

225-216-4

EC Name:

Octadecylphosphonic acid

Cas Number:

4724-47-4

Molecular formula:

C18H39O3P

IUPAC Name:

octadecylphosphonic acid

impurity 2

Reference substance name:

Dimethyl octadecylphosphonate

EC Number:

246-904-0

EC Name:

Dimethyl octadecylphosphonate

Cas Number:

25371-54-4

Molecular formula:

C20H43O3P

IUPAC Name:

dimethyl octadecylphosphonate

Test material form:

solid

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

Animals were housed individually in suspended stainless steel cages. All housing and care were based on the standards recommended by the Guide for the Care and Use of Laboratory AnimalsEnvironmental ConditionsRoom temperature: 20-23°CRelative Humidity: 39-59%Light cycle: 12-hour light/ 12-hour dark cycleRoom ventilation: 10-15 air changes/hour

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

On day -1, the animals chosen for the limit test were weighed and fasted overnight. Pnr day 0, the test article was administered orally as a single dose using a ball tipped stainless steel gavage needle attached to a syringe

Doses:

2000 mg/kg

No. of animals per sex per dose:

5 females/ dose group

Control animals:

no

Details on study design:

A limit test was performed in which one female rat was initially dosed a single oral administration fo the test article at a dose of 2000 mg/kg body weight. Two further female rats received a single oral administration of the test article at the same dose level. The study was then completed with two additional females. Following dosing, the rats were observed daily and weighed weekly. A gross necropsy examination was performed on all animals at the time of scheduledd euthanasia (day 14).

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred during the study.

Clinical signs:

Clinical signs of toxicity oberved during th study included transient incidences of congested breathing, few feces, soft stools, mucoid stools, feces small in size, rough coat and fecal stain.

Body weight:

Slight body weight loss was noted in one female furing the study day 7 to 14 body weight interval. Body weight gain was noted for all other animals during the test period.

Gross pathology:

No gross internal findings were observed at necropsy on study day 14.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the results of this study the LD50 value of Phosphonic acid, octadecyl,-monomethyl ester is considered to be > 2000 mg/kg body weight

Executive summary:

A limit test was performed in which one female was initially dosed a single oral administration of test article at a dose of 2000 mg/kg body weight. Since there were no clinical observations, two additional female rats received a single oral administration of the test article at the same dose level. The study was then completed with additional females. No mortality occured during the study. Clinical signs of toxicity were limited to transient incidences of congested breathing, few feces, soft stools, feces small in size, rough coat and fecal stain. Slight body weight loss was noted in one female during study day 7 to 14. No gross internal findings were observed at necropsy on study day 14.

Under the conditions of this test, the acute oral LD50 of Phosphonic acid, octadecyl,-monomethyl ester is considered to be > 2000 mg/kg body weight.