Reassessment of paraquat

Decision Date: 11 December 2019

The reassessment application for paraquat has been decided and the decision is published.

Reassessment decision

We have reassessed the use of the herbicide paraquat.

An EPA Decision-making Committee (DMC) has placed greater controls on approved paraquat herbicides. The key controls are:

  • Paraquat is restricted to horticultural and agricultural use only, and some biosecurity use is allowed with permission.
  • Restrictions on the rate that paraquat can be applied, and restrictions to spray droplet size.
  • Revised downwind buffer zones to protect aquatic environments and plants.

Product manufacturers and importers must develop and provide improved safety information for users. The information must detail how to safely handle paraquat herbicides, from storage, through to disposal, and keeping the environment safe when applying them.

Manufacturers, importers, suppliers and certified handlers have a period of time to ensure the new controls and restrictions take effect. The key changes will be phased in over the next 12 months, with labels to be updated within 24 months.

The committee has also decided that as of December 2020, Uniquat 250, Parable 250, Gramoxone Inteon and Preeglone Inteon can no longer be sold or used in New Zealand.

Read the full paraquat reassessment decision (pdf 1.5MB)


Paraquat is included in our priority chemicals list, which was unveiled in October 2018 as part of our revamped reassessments programme. It is the first active ingredient from the priority chemicals list to be reassessed.

Grounds to reassess paraquat were granted in July 2017, based on new information obtained in an application for a paraquat-containing formulation that was declined in 2016.

The public was invited to participate in the call for information period from 1 July to 31 August 2017.

An application for reassessment was then made which contained further refined human health and environmental risk assessments, as well as an economic benefits assessment. Proposals were made relating to the fate of paraquat-related approvals. The reassessment application was open for public submission between 28 February and 30 April 2019. 

Information provided by submitters in the consultation process was used to inform the revised assessments and proposals which is presented in the update report.

The hearing for the paraquat reassessment was held in Wellington on 11 and 12 September 2019. The hearing was adjourned on 12 September 2019 and officially closed on 14 October 2019.

The application documents

The documents related to the paraquat reassessment application are available below. These are listed by the phase of the application they relate to. The phases are listed chronologically – the most recent phase is shown first.


Read the decision document of Paraquat (pdf 1.5MB)

The approval documents for reapproved paraquat substances:

Read the approval document for HSR000447 (pdf 838KB)

Read the approval document for HSR000828 (pdf 821KB)

Read the approval document for HSR003041 (pdf 404KB)


The hearing was transcribed:

Read the transcript of the hearing on 11 September 2019 (pdf 554KB)

Read the transcript of the hearing on 12 September 2019 (pdf 296KB)

EPA staff and submitters presented slides during the hearing:

View the EPA staff and submitter hearing presentation slides

A submitter raised some queries via email following the adjournment of the hearing on 12 September, which we responded to on 14 October:

Read our response to a submitter's queries (pdf 307KB)

The Decision-making Committee issued a direction and minute to acknowledge the submitter's queries, and to formally close the hearing:

Read the Decision-making Committee's direction and minute (pdf 232KB)

Update report

The update report contains our updated proposals, revised from those presented in the application form and informed by the information provided in the submission period.

Read the update report for reassessment of paraquat (pdf 1.2MB)


There are a number of appendices supporting the update report:

Information request

Following the submission period, we requested information from Biosecurity New Zealand regarding paraquat use in biosecurity.

Read our information request to Biosecurity New Zealand (pdf 710KB)

View Biosecurity New Zealand’s response to our enquiry (pdf 208KB)


We received 18 submissions during the public submission period. 

View the submissions

Reassessment application form

The application form contains our initial proposals for paraquat and paraquat-containing substances.

Read the paraquat reassessment application form (pdf 1.5MB)


There are a number of appendices supporting the reassessment application form:

Background documents

Read the documents for the application for grounds for reassessment

Read the documents for the declined application