Skip to content

The regulation of inhibitors used in agriculture

UPDATE – 18 May 2022

Policy proposals approved to regulate inhibitors under the ACVM Act 1997

In March 2021, Cabinet:

  • agreed to strengthen the regulation of inhibitors used in agriculture by defining inhibitors as agricultural compounds, causing them to be regulated under the ACVM Act.
  • noted that agrichemical companies need time to register inhibitors under the ACVM Act, which led to a 2-year transitional period.

Cabinet paper: Proposals to strengthen regulatory oversight of inhibitors used in agriculture [PDF, 4 MB]

Bringing Inhibitors under the ACVM Act

To bring inhibitors under the ACVM  Act requires an interim measure and a permanent solution.

Subject to Cabinet decisions, the interim measure:

  • declares listed inhibitors as agricultural compounds by an Order in Council
  • creates a 2-year transitional period for product registration for those currently for sale in New Zealand
  • is intended to come into effect in July 2022.

Listed inhibitors would be eligible for registration under the ACVM Act. If products are currently for sale in New Zealand, they can continue to be sold during the transitional period while product registration is sought.

The permanent solution is to amend the definition of agricultural compound in the ACVM Act to include inhibitors. This will ensure that all inhibitors will be regulated under the ACVM Act and be eligible for registration. More information on this will be available soon.

Find out more

Regulation of inhibitors under the ACVM Act – FAQ [PDF, 229 KB]

For enquiries about this work, email

For enquiries about the registration process, email the ACVM Team at

About this consultation

The Ministry for Primary Industries (MPI) sought feedback on options to change the way inhibitors used in agriculture are managed. The discussion paper identified 3 options for managing the regulatory oversight of inhibitors to make sure the primary sector could safely and effectively use inhibitors to mitigate environmental, sustainability and climate change issues. It also sought feedback on key details – for example, the definition of inhibitor, should the level of regulatory oversight of inhibitors increase.

What are inhibitors?

The consultation ran from 13 February to 5 April 2020.

Discussion paper

The regulation of inhibitors used in agriculture [PDF, 1021 KB]

Related information

One page summary of the discussion paper [PDF, 129 KB] 

Media release about this consultation

Questions and answers about this consultation [PDF, 71 KB]

What was proposed?

MPI identified and is sought feedback on 3 options for managing inhibitors used in agriculture.

Option 1: Maintain the status quo

No change to how inhibitors are regulated. Involves the least compliance cost to industry and maintains current access to inhibitors. 

Option 2: Increase industry management of inhibitors

A non-regulatory option. This would require those involved in selling inhibitors working with users to ensure there is sufficient information provided to manage risks to animal and plant health, food safety, and trade.   

Option 3: Change the regulation of inhibitors

Legal obligations would apply. Inhibitors could be identified as agricultural compounds and the risks managed by assessments under the Agricultural Compounds and Veterinary Medicines Act 1997.

Questions we asked you

We asked for feedback on these questions:

  • Should regulatory oversight of inhibitors be increased?
  • What is the most appropriate of the 3 options identified (or is there a better alternative)?
  • What are the key regulatory settings should oversight increase?
  • What are the impacts of the identified options?
  • Are there any potential unintended consequences of the proposed options?

Submissions are public information

Note, that any submission you make becomes public information. People can ask for copies of submissions under the Official Information Act 1982 (OIA). The OIA says we have to make submissions available unless we have good reasons for withholding them. That is explained in sections 6 and 9 of the OIA.

Tell us if you think there are grounds to withhold specific information in your submission. Reasons might include that it is commercially sensitive or it's personal information. However, any decision MPI makes to withhold information can be reviewed by the Ombudsman, who may tell us to release it.

MPI may post all or parts of any written submission on its website. We'll consider that you have consented to its publication unless clearly stated otherwise in your submission.  

What are inhibitors?

Inhibitors are potentially important tools for primary producers to improve environmental sustainability. While there is no legislated definition of inhibitor in New Zealand, they are commonly considered to be compounds that can be applied directly or indirectly to animals or a place to inhibit the production of greenhouse gases or to reduce nutrient leaching in some way. Inhibitors vary widely in how and what they inhibit. Common types of application include as feed additives, coatings on fertilisers, or vaccines.

There is growing interest by farmers and growers in the use of these tools to reduce nitrate leaching and the effects of climate change. While this technology has some exciting potential, we need to make sure that any use of inhibitors is managed well so that any potential risks to food safety, plant and animal health and trade are minimised. As well as making sure there are no negative impacts from using inhibitors, the primary sector wants assurance that products on the market that claim to be inhibitors are effective.