Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information

A skin sensitisation study was not conducted because phosphonic ester residue is classified as skin corrosive category 1A (H314).


However, according to GHS/CLP 1972/2008 section 3.4.3.3. phosphonic ester residue has to be classified as category 1B skin sensitizer (H317) since its component dimethyl phosphonate (CAS 868-85-9) is a classified category 1B skin sensitizer (H317) based on read across from diethyl phosphonate (CAS 762-04-9).

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion
Additional information:

There no data available on phosphonic ester residue with respect to skin sensitization .


Phosphonic ester residue contains monomethyl phosphonate, phosphonic acid, and Dimethylphosphonate, and and salt of pyrophosphoric acid. and phosphate which were not further specified


According to Regulation (EC) 1907/2006 (REACh) ANNEX VII section 8.3 column 2 a study needs not to be conducted because the available information indicates that the substance should be classified for corrosivity.


The only available information resulted fron read acrosss consideration for Dimethylhydrogenphosphite accounting for 11 % in phosphonic ester residue. The compound which was taken into account yielded sensitizing effects in a Guinea Pig Maximization Test. This result leads to the respective classification Category 1b for skin sensitizers H317= may cause an allergic skin reaction.


For all other ingredients there are no data available with respect to skin sensitization.


Based on the available data from dimethylhydrogenphosphite evaluation smf taking into account the requirements of GNS/CLP 1272/2008, phosphonic ester residue has to be regarded as skin sensitizer.

Short description of key information:
There is no study with phosphonic ester residue available with respect to skin sensitization. According to Regulation (EC) 1907/2006 (REACh) ANNEX VII section 8.3 column 2 a study needs not to be conducted because the available information indicates that the substance should be classified for corrosivity. However, based on the available data from dimethylhydrogenphosphite evaluation, phosphonic ester residue has to be regarded as skin sensitizer.

Justification for selection of skin sensitisation endpoint:
There is no study with phosphonic ester residue available with respect to skin sensitization. However, according to Regulation (EC) 1907/2006 (REACh) ANNEX VII section 8.3 column 2 a study needs not to be conducted because the available information indicates that the substance should be classified for corrosivity.

Justification for classification or non-classification

There no data available on phosphonic ester residue with respect to skin sensitization. Based on the available information on corrosive property no further testing is required. However, according to GHS/CLP 1972/2008 section 3.4.3.3. a mixture shall be classified as a skin sensitizer when at least one ingredient has been classified as skin sensitizer and is present at or above the 1% (generic concentration limit).


Dimethylphosphonate accounting for 11 % in phosphonic ester residue, is classified and labelled by the producer with Category 1b for skin sensitizers H317= may cause an allergic skin reaction.


Consequently, classification/labelling is required for phosphonic ester residue.