Iron orthophosphate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Between 24 November 2011 and 20 December 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 bis (Acute Oral Toxicity - Fixed Dose Procedure)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Iron orthophosphate

EC Number:

233-149-7

EC Name:

Iron orthophosphate

Cas Number:

10045-86-0

Molecular formula:

FePO4

IUPAC Name:

iron(3+) phosphate

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

Female Wistar (RccHan™:WIST) strain rats were supplied by Harlan Laboratories UK Ltd., Oxon, UK. On receipt the animals were randomly allocated to cages. The females were nulliparous and non-pregnant. After an acclimatisation period of at least five days the animals were selected at random and given a number unique within the study by indelible ink marking on the tail and a number written on a cage card. At the start of the study the animals were eight to twelve weeks of age. The bodyweight variation did not exceed ±20% of the bodyweight of the initially dosed animal.
The animals were housed in groups of up to four in suspended solid floor polypropylene cages furnished with woodflakes. With the exception of an overnight fast immediately before dosing and for approximately three to four hours after dosing, free access to mains drinking water and food (2014C Teklad Global Rodent diet supplied by Harlan Laboratories UK Ltd., Oxon, UK) was allowed throughout the study. The diet, drinking water and bedding were routinely analysed and were considered not to contain any contaminants that would reasonably be expected to affect the purpose or integrity of the study.
The temperature and relative humidity were set to achieve limits of 19 to 25°C and 30 to 70% respectively. Any occasional deviations from these targets were considered not to have affected the purpose or integrity of the study. The rate of air exchange was at least fifteen changes per hour and the lighting was controlled by a time switch to give twelve hours continuous light (06:00 to 18:00) and twelve hours darkness.
The animals were provided with environmental enrichment items which were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

All animals were dosed once only by gavage, using a metal cannula attached to a graduated syringe.

Doses:

300 mg/kg
2000 mg/kg

No. of animals per sex per dose:

1 female at 300 mg/kg
1 female at 2000 mg/kg
4 females at 2000 mg/kg

Control animals:

no

Details on study design:

All animals were dosed once only by gavage, using a metal cannula attached to a graduated syringe. The volume administered to each animal was calculated according to the fasted bodyweight at the time of dosing. Treatment of animals was sequential. Sufficient time was allowed between each dose level to confirm the survival of the previously dosed animals.
Clinical observations were made ½, 1, 2, and 4 hours after dosing and then daily for fourteen days. Morbidity and mortality checks were made twice daily.
Individual bodyweights were recorded on Day 0 (the day of dosing) and on Days 7 and 14.
At the end of the observation period the animals were killed by cervical dislocation. All animals were subjected to gross necropsy. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded. No tissues were retained.

Results and discussion

Preliminary study:

Dose Level - 300 mg/kg
Individual clinical observations and mortality data are given in Table 1.

Mortality
There was no mortality.

Clinical Observations
No signs of systemic toxicity were noted during the observation period.

Bodyweight
Individual bodyweights and bodyweight changes are given in Table 2.
The animal showed expected gains in bodyweight over the observation period.

Necropsy
Necropsy findings are given in Table 3.
No abnormalities were noted at necropsy.

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

Dose Level - 2000 mg/kg
Individual mortality data are given in Table 4.
There were no deaths.

Clinical signs:

other: Dose Level - 2000 mg/kg Individual clinical observations are given in Table 4. No signs of systemic toxicity were noted during the observation period.

Gross pathology:

Dose Level - 2000 mg/kg
Individual necropsy findings are given in Table 6.
No abnormalities were noted at necropsy.

Other findings:

None

Any other information on results incl. tables

Evaluation of Data

Data evaluations included the relationship, if any, between the animals' exposure to the test item and the incidence and severity of all abnormalities including behavioural and clinical observations, gross lesions, bodyweight changes, mortality and any other toxicological effects. If possible the signs of evident toxicity were also identified. Evident toxicity is defined as the toxic effects which are of a severity such that administration at the next highest level could result in mortality.

Using the mortality data obtained, an estimate of the acute oral median lethal dose (LD₅₀) of the test item was made.

Table 1              Individual Clinical Observations and Mortality Data - 300 mg/kg

Dose Level mg/kg	Animal Number and Sex	Effects Noted After Dosing (Hours)				Effects Noted During Period After Dosing (Days)
		½	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
300	1-0 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0=     No signs of systemic toxicity

Table 2              Individual Bodyweights and Bodyweight Changes - 300 mg/kg

Dose Level mg/kg	Animal Number and Sex	Bodyweight (g) at Day			Bodyweight Gain (g) During Week
		0	7	14	1	2
300	1-0 Female	160	167	194	7	27

Table 3              Necropsy Findings - 300 mg/kg

Dose Level mg/kg	Animal Number and Sex	Time of Death	Macroscopic Observations
300	1-0 Female	Killed Day 14	No abnormalities detected

Table 4              Individual Clinical Observations and Mortality Data - 2000 mg/kg

Dose Level mg/kg	Animal Number and Sex	Effects Noted After Dosing (Hours)				Effects Noted During Period After Dosing (Days)
		½	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	2-0 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-0 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-1 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-2 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-3 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0=     No signs of systemic toxicity

Table 5              Individual Bodyweights and Bodyweight Changes - 2000 mg/kg

Dose Level mg/kg	Animal Number and Sex	Bodyweight (g) at Day			Bodyweight Gain (g) During Week
		0	7	14	1	2
2000	2-0 Female	158	171	190	13	19
	3-0 Female	160	182	193	22	11
	3-1 Female	168	190	207	22	17
	3-2 Female	161	183	208	22	25
	3-3 Female	168	189	209	21	20

 Table 6             Individual Necropsy Findings - 2000 mg/kg

Dose Level mg/kg	Animal Number and Sex	Time of Death	Macroscopic Observations
2000	2-0 Female	Killed Day 14	No abnormalities detected
	3-0 Female	Killed Day 14	No abnormalities detected
	3-1 Female	Killed Day 14	No abnormalities detected
	3-2 Female	Killed Day 14	No abnormalities detected
	3-3 Female	Killed Day 14	No abnormalities detected

Applicant's summary and conclusion

Interpretation of results:

other: CLP/EU GHS criteria are not met, no classification required according to Regulations (EC) No 1272/2008

Conclusions:

The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg bodyweight (Globally Harmonised Classification System - Unclassified). This study is considered to be scientifically justified for use as a key study under Regulation (EC) No. 1907/2006 and the results are appropriate for the purposes of classification and labelling in accordance with Regulation (EC) No. 1272/2008 (EU CLP).

Executive summary:

Introduction. The study was performed to assess the acute oral toxicity of the test item in the Wistar strain rat. The method was designed to be compatible with the following:

OECD Guidelines for Testing of Chemicals No 420 “Acute Oral Toxicity - Fixed Dose Method” (2001)

Method B1bis Acute Toxicity (Oral) of Commission Regulation (EC) No. 440/2008

Method. Following a sighting test at dose levels of 300 mg/kg and 2000 mg/kg, a further group of four fasted females was given a single oral dose of test item, as a suspension in distilled water, at a dose level of 2000 mg/kg bodyweight. Clinical signs and bodyweight development were monitored during the study. All animals were subjected to gross necropsy.

Mortality. There were no deaths.

Clinical Observations. There were no signs of systemic toxicity.

Bodyweight. All animals showed expected gains in bodyweight.

Necropsy. No abnormalities were noted at necropsy.

Conclusion. The acute oral median lethal dose (LD₅₀) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg bodyweight (Globally Harmonised Classification System - Unclassified).