Media release
EPA approves herbicides to control aquatic pest plants
A decision-making Committee of the Environmental Protection Authority (EPA) has approved, with specific additional
controls, an application to allow a number of herbicides to be used to control aquatic pest plants.
The application by the Agricultural Reassessment Group (ARG) was made on behalf of 12 regional councils, as well as the
Department of Conservation, Ministry for Primary Industries, Land Information New Zealand and Mighty River Power. The
application related to herbicides containing one of four active ingredients: haloxyfop-R-methyl; imazapyr
isopropylamine; metsulfuron-methyl; or triclopyr triethylamine. These herbicides are approved for use on land in New
Zealand and are used by the applicant group to control a range of pest plant species. Many pest plants also inhabit
aquatic environments. The ARG sought approval for the application of these substances onto or into water for the control
of aquatic pest plants.
Twenty-eight submissions were received on the application, with eight submitters requesting to be heard. A hearing was
held before the Committee in Hamilton on 31 October.
After weighing the evidence of all submitters, the Committee decided that agrichemical control, using the substances in
the application, was more likely to achieve the benefits of controlling aquatic pest plants than other means of
controlling them, and concluded there would be significant benefits to New Zealand from the application of these
substances onto or into water, subject to controls.
The Committee noted in its decision that the information provided included a number of data gaps, meaning EPA staff were
unable to undertake a comprehensive assessment of the impacts of the application of these substances onto or into water.
The Committee therefore considered additional controls were necessary to manage potential risks to human health, the
environment and the relationship between Maori and the environment, and the uncertainty associated with the effects of
the application of the substances onto or into water.
These additional controls include:
• Setting exposure limits to control the amount of these substances entering the environment to limit the risk to
people and to organisms in the environment.
• Requiring users to obtain permission to use these substances to ensure relevant site-specific considerations are
addressed.
• Requiring these substances to be under the personal control of an approved handler during any application into
or onto water.
• Anyone applying the substances must ensure they are not applied in a manner that may cause harm to aquatic farms
where food is produced.
• Anyone applying the substances into or onto water must ensure they are not applied in a manner that may cause
harm to crops using water taken from that water body (irrigation water).
• Specific and detailed warning sign requirements in application areas.
• Notification of any potentially directed parties, including providing details of treatment dates, identify of
substance being used and relevant restrictions on water use at least five working days prior to each application of the
substance.
• Ensuring the substances are not applied onto or into bodies of water where whitebait or elvers may be present
during the Department of Conservation’s defined local whitebait season relevant to that region.
• Prohibiting the application onto or into water of any substance containing nonylphenol ethoxylates as part of
the formulation.
• Ensuring the substances are not applied in any single application onto more than 33% of the surface area of any
static body of water and restrictions related to cumulative use in static water.
• Incident reporting requirements.
• Annual reporting to the EPA covering all applications of these substances onto or into water.
More details about these controls are outlined in the full decision document. http://www.epa.govt.nz/search-databases/Pages/applications-details.aspx?appID=APP201365
ENDS