Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Mecoprop-P n-octyl ester hydrolyses rapidly in natural water. Therefore, the hydrolysis product Mecoprop-P acid (MCPP-P acid) was used for further risk assessment of Mecoprop-P n-octyl ester in the environment.

Since Mecoprop-P acid (MCPP-P acid) is reviewed under Directive 91/414/ECC an extensive data package is available for this active substance. Therefore, only those data with the lowest effect value are described in this Chemical Safety Assessment. Anyhow, the results are scored to be reliable, and are taken into account for the evaluation of the hazardous potential of Mecoprop-P n-octyl ester in the environment.


The following endpoints were determined for the hydrolysis product Mecoprop-P acid (MCPP-P acid):

In a short-term toxicity test to fish a 96h-LC50 of 76 mg/L and a 96h-NOEC of 42 mg/L were determined.

The results for an acute toxicity test on Daphnia magna were a 48h-EC50 > 91 mg/L and a 48h-NOEC of 91 mg/L.

In a semi static test system a 21d-NOEC of 22.2 mg/L was determined related to reproduction on Daphnia magna.

A 72h-EC50 of 23.9 mg/L and a 72h-NOEC of 5.96 mg/L were determined on the alga Anabaena flos-aquae. Based on these results alga is considered as the most sensitive species for Mecoprop-P n-octyl ester and its hydrolysis product Mecoprop-P acid (MCPP-P acid).

The effect of Mecoprop-P acid (MCPP-P acid) to growth inhibition on Pseudomonas putida was investigated, and the effect values were a 17h-EC50 of 170 mg/L and a 17h-NOEC of 12 mg/L.