23: 04: 2026
The MPS List of Prohibited Active Substances is a key component of the MPS-ABC and MPS-Compact certification standards. Its purpose is to progressively reduce the use of chemicals that
pose risks to human health and the environment, supporting a more sustainable ornamental horticulture sector.
This update highlights three important changes to the list that growers and certified participants should take note of.
New additions from P5 2026
As previously communicated, four new active substances will be added to the prohibited list starting from period P5 2026, effective 20 April 2026. From this date, audits will be conducted based on the updated list.
In the MPS record-keeping system, these substances will be flagged with a black dot whenever a product containing them is recorded.
The newly added substances are:
- tributyltin oxide
- dimoxystrobin
- ipconazole
- methoxychlor
Further additions from P5 2027
A second group of substances will be added to the prohibited list starting from P5 2027. These chemicals have been identified as hazardous based on their inclusion in at least two internationally recognised regulatory or advisory lists, including the Stockholm Convention on Persistent Organic Pollutants (POP), the Rotterdam Convention (PIC), PAN Dirty Dozen list, the US EPA restricted pesticides list, the EU pesticide database, and WHO Class Ia and Ib classifications.
The substances being added are:
| Active substance | Relevant listing | Main application |
| chloropicrin | EPA (RUP) and EU | Insecticide, nematicide |
| fonofos | EPA (RUP) and EU | Insecticide |
Growers currently using these substances are encouraged to begin phasing them out early. MPS will continue to support participants through guidance and updates to help achieve full compliance ahead of implementation. Please stay informed through official communications, including the digital newsletter.
Substances removed from the list
Based on updated assessments and new insights, the following substances have been removed from the MPS List of Prohibited Active Substances:
- brodifacoum
- bromadiolone
- coumatetralyl
- difenacoum
- difethialone
- flocoumafen
These substances may now be used again where permitted under national laws and regulations applicable in the country of operation.
Stay updated
The most recent version of the MPS List of Prohibited Active Substances is available on the official MPS website.