Phosphinic acid

Eye irritation

Administrative data

Endpoint:

eye irritation, other

Remarks:

other: alkaline reserve

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Test procedure in accordance with generally accepted scientific standards and described in sufficient detail.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Supplement of guidelines 404 and 405 recommends the sequential testing strategy (including pH and alkaline reserve measurements) prior to undertaking the in vivo tests corrosion/irritation of the substance.
The method used in the study which permits the measurement of pH and Alkaline reserve to identify chemicals potentially corrosive to the skin and to the eye was described in V.Froment (1993) and JF.Regnier & C. Imbert (1992), respectively.

Criteria for eye irritation:
The test item is considered at potentially severely irritant to the eye if at least 2 of the 3 following criteria are fulfilled:
- pH <= 2,5 / pH >= 9,5
- log R >= 0, with the R corresponding to the alkaline reserve
- I >= 9, with the I corresponding to the physicochemical index, defined as a weighting of the pH by the decimal logarithm of the Alkaline reserve
I = pH + log R for pH >= 7
I = (14 - pH) + log R for pH < 7

Criteria for skin corrosion :The test item is corrosive to the skin if at least 2 of the 3 following criteria are fulfilled:
- pH <= 2,5 or pH >= 9,5
- log R >= 0
- I >= 10

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Phosphinic acid

EC Number:

228-601-5

EC Name:

Phosphinic acid

Cas Number:

6303-21-5

Molecular formula:

H3O2P

IUPAC Name:

phosphinic acid

Test material form:

other: aqueous solution

Details on test material:

Sample designation:
- Name of test material: Phosphinic acid
- Physical state: clear liquid
- Date of reception in the test facility: 2009.12.23
- Expiration date of the test item: December 2011
- Batch number: 08-27
- Other characteristics:
relative density at 20°C: 1.2662
purity: 61%
water solubility: soluble (20°C) according to SDS

Certificate of analysis :
- Analysis number: 2009-03075-001

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

other: pH, alkaline reserve R, physicochemical index I

Basis:

other: pH, alkaline reserve R, physicochemical index I

Time point:

other: pH

Score:

0.71

Remarks on result:

other: for 100g/L solution in water

Results 2

Irritation parameter:

other: pH, alkaline reserve R, physicochemical index I

Basis:

other: pH, alkaline reserve R, physicochemical index I

Time point:

other: alkaline reserve R

Score:

38.015

Remarks on result:

other: log R = 1.580

Results 3

Irritation parameter:

other: pH, alkaline reserve R, physicochemical index I

Basis:

other: pH, alkaline reserve R, physicochemical index I

Time point:

other: physicochemical index I

Score:

14.87

Irritant / corrosive response data:

Under the test conditions, the aqueous phosphinic acid shows an acidic character demonstrated by a pH of 0.71 for a 100 g/L solution in water, analkaline reserve of 38,015 (i.e log R = 1,580) and a physicochemical index of 14,870.

According to the method, the test item is considered:
- as potentially corrosive to the skin as the 3 criteria are fullfilled.
pH <= 2,5 or pH >= 9,5
log R >= 0
I >= 10
- as potentially severely irritant to the eye as the 3 criteria are fullfilled.
pH <= 2,5 or pH >= 9,5;
log R >= 0
I >= 9

As the 3 criteria are fullfilled for both end-points, hypophosphorous acid can be considered as potentially corrosive to the skin and severely irritant to the eye.

Any other information on results incl. tables

Under the test conditions, the aqueous phosphinic acid shows an acidic character demonstrated by a pH of 0.71 for a 100 g/L solution in water, an alkaline reserve of 38.015 (i.e log R = 1.580) and a physicochemical index of 14.870.

Table 1 : Results of neutralization experiments

Replicate  Hypophorous acid 100 g/L, mL  NaOH 0,1 N, mL Initial pH  Final pH   R  Log (R)  I  1  10 95,110  0,71  7,01         38,015   1,580      14,870     2  10 95,160 0,71 7,04  3  10 95,190 0,71 7,01

Applicant's summary and conclusion

Interpretation of results:

highly irritating

Remarks:

Migrated information Criteria used for interpretation of results: expert judgment

Conclusions:

According to the method, the test item is considered:
- as potentially corrosive to the skin as the 3 criteria are fullfilled.
pH <= 2,5 or pH >= 9,5
log R >= 0
I >= 10
- as potentially severely irritant to the eye as the 3 criteria are fullfilled.
pH <= 2,5 or pH >= 9,5;
log R >= 0
I >= 9

As the 3 criteria are fullfilled for both end-points, phosphinic acid can be considered as potentially corrosive to the skin and severely irritant to the eye.

Executive summary:

The pH and Alkaline reserve of the test item phosphinic acid was measured according to the method described in the two following references JF.Regnier and C.Imbert (1992), and V.Froment (1993).

Criteria for eye irritation:

The test item is considered at potentially severely irritant to the eye if at least 2 of the 3 following criteria are fulfilled:

- pH <= 2,5 / pH >= 9,5

- log R >= 0, with the R corresponding to the alkaline reserve

- I >= 9, with the I corresponding to the physicochemical index, defined as a weighting of the pH by the decimal logarithm of the Alkaline reserve

I = pH + log R for pH >= 7

I = (14 - pH) + log R for pH < 7

Criteria for skin corrosion :

The test item is corrosive to the skin if at least 2 of the 3 following criteria are fulfilled:

- pH <= 2,5 or pH >= 9,5

- log R >= 0

- I >= 10

This method can be used at first step of stepwise strategy for assessing cutaneous and ocular irritation.

An amount of the test substance is added to distilled water in a beaker. The solution or suspension is maintained for 4 hours with agitation at 37° C. The pH is directly measured and the sample is then titrated with diluted sodium hydroxide or hydrochloric acid until neutrality is obtained. The acidic or alkaline reserve (R) is expressed as the number of grams of pure acid or base necessary to neutralise 100 g of product (%).

A preliminary titration was performed for a preliminary test to allows good conditions for the alkaline reserve (R) determination: 10 mL volume of a 100 g/L solution are neutralised by approximately 95 mL of 0.1 N NaOH. Then for a definitive test, the titration were performed three times more in the same conditions.

Under the test conditions, the aqueous phosphinic acid shows an acidic character demonstrated by a pH of 0.71 for a 100 g/L solution in water, an alkaline reserve of 38.015 (i.e log R = 1.580) and a physicochemical index of 14.870.

According to the method described, as all the criteria are fullfilled, Phosphinic acid can be considered as potentially corrosive to the skin and severely irritant to the eye.