Phosphonic acid, calcium salt (2:1)

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013, January

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Test material

Test material information

Constituent 1

Reference substance name:

Potassium Phosphonate KH2PO3/K2HPO3

IUPAC Name:

Potassium Phosphonate KH2PO3/K2HPO3

Details on test material:

Batch number :20111216-014Expiry date :16 December 2013Storage at RTC :Room temperatureCertificate of analysis:Supplied by the Sponsor and presented in Addendum ITest item characterisation :Not undertaken at the testing facility. The determination of the identity, strength, purity, composition, stability and method of synthesis and/or derivation of the test item was the responsibility of the SponsorSample archiving:Retained within RTC archives for a period of 10 years prior to disposal.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

Age and weight range :6 to 8 weeks old, 176 to 200 grams(at order)Supplier :Charles River Italia S.p.A., Calco (Lecco), ItalyBreeder :Charles River Italia S.p.A., Calco (Lecco), ItalyDate of arrival :17 January 2013Weight range at arrival:201 to 206 grams Acclimatisation period:At least 5 daysVeterinary health check:After arrivalCagingNo. of animals/cage:Individually caged (both during acclimatisation and study)Housing :Clear polysulphone H-Temp solid bottomed cages measuring 35.5x23.5x19 cm (during acclimatisation) an d 42.5x26.6x18.5 cm (during the study) with nesting material provided into suitable bedding bagsCage control :Daily inspected and changed as necessary (at least 3 times/week)Water and dietWater :Drinking water supplied to each cage via a water bottleWater supply :Ad libitumDiet :4 RF 18 (Mucedola S.r.l., Via G. Galilei, 4, 20019, Settimo Milanese (MI) Italy)Diet supply :Ad libitum throughout the study Records of analyses of water and diet are kept on file at RTC. Components present in the drinking water or diet are not at a level likely to interfere with the purpose or conduct of the study.Housing conditions (parameters set)Room lighting: :Artificial (fluorescent tubes), daily light/dark cycle of 12/12 hours Air changes: :Approximately 15 to 20 air changes per hourTemperature range::22°C ± 2°C Relative humidity range::55% ± 15%Actual conditions were monitored, recorded and records retained. No relevant deviations occurred

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

water

Details on dermal exposure:

Frequency of treatment:Once only, on the day of dosing (Day 1).Treatment area preparation:On the day before dosing (Day –1).A single area was clipped free of hair (by an electric clipper equipped with a suitable blade) on the dorsal surfaces of the trunk of each animal, (approximately 10% of body surface).Care was taken to avoid damage to the skin.Dose calculation:Aliquots were weighed according to the body weight of each animal measured prior to dosing and corrected for purity (50%).

Duration of exposure:

Exposure time :24 hoursWashing procedure:After exposure, the adhesive bandage and gauze patch were removed. The treatment area was cleaned by gentle swabbing of the skin with cotton wool soaked with lukewarm water.

Doses:

5000 mg/Kg bw

No. of animals per sex per dose:

A single group of 5 male and 5 female animals was dosed at a level of 5000 mg/kg

Details on study design:

In life observationsMortality and morbidity:Twice daily.Clinical signs :-Day of dosing (on dosing, approximately 1, 2 and 4 hours after dosing). -Daily thereafter (14 days).Body weight :Allocation (Day -1), Days 1, 8 and 15.Terminal studiesTermination :Day 15.Euthanasia method:Carbon dioxide narcosis.Necropsy procedure:Necropsy was carried out on all animals (gross necropsy examination for both external and internal abnormalities, with particular attention to the treatment site).

Results and discussion

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LD0

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Effect levels 2

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred and no clinical signs were observed in male or female animals following treatment

Gross pathology:

No abnormalities were found at necropsy examination performed on all animals at termination of the study

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

LD0 > 5000 mg/kg bw LD50 > 5000 mg/kg bw

Executive summary:

The acute toxicityof KH₂PO₃/K₂HPO₃was investigated following dermal administration of a single dose to the rat at 5000 mg/kg.

No mortality occurred following dosing and no signs of toxicity were observed.

These results indicate that the test item, KH₂PO₃/K₂HPO₃, has no toxic effect on the rat following dermal exposure over a 24 hour period at a level of 5000 mg/kg. The lack of mortality demonstrates the LD50 to be greater than 5000 mg/kg.