Safe use of products to kill fleas, flies and other insects

We have issued a caution notice to alert consumers to risks posed by over-the-counter products which contain synthetic pyrethroids to kill insects.

Caution notice

1 November 2018

The chemicals are used in a variety of settings, including in some fly sprays, insect repellents, automatic insect dispensers, bed bug treatments, and animal flea collars and treatments.

We are not aware of any specific incidents in New Zealand relating to the use of fly sprays or home-use insecticides. There may be some instances that go unreported. This caution notice aims to promote, maintain and enhance consumer safety.

Products containing synthetic pyrethroids are still safe to use as long as the instructions for use on the product's label are followed. It is always a good idea to keep children and pets away from areas where household insecticides are being used.

Good practice for safe use of these products Plus

Personal Protection

  • Wear non-absorbent gloves when handling the product. When you're finished, wash your hands and all areas of exposed skin with soap and water. Wash gloves thoroughly after each use.
  • Always wear the appropriate personal protective equipment which may include wearing clothes that fully cover arms and legs and using eye protection such as safety glasses.

First Aid

  • If the product is ingested, contact a doctor immediately and call the National Poisons Centre on 0800 764 766.
  • If product gets in your eyes, wash thoroughly with water; remove and wash any contaminated clothing.
  • Seek medical assistance if the symptoms persist.

Protecting non-target animals

  • Keep pets out of the room when using fly sprays and avoid using on furniture or surfaces that they are likely to come in contact with.
  • When using flea treatments on pets ensure you follow the label carefully.
  • Ensure fish tanks are covered when spraying fly sprays or insecticides.


  • Contain the spill using an absorbent material (such as sand or clay) and block off from entering any drains. Dispose of this by following the instructions on the label. Wash the affected area with water and detergent.


  • Dispose of empty containers according to the label directions.
Storage and use of synthetic pyrethroids Plus

To safely store and use synthetic pyrethroids, always: 

  • Follow the manufacturer’s directions for storage and use as stated on the packet. Store in clearly labelled, sealed containers, well out of the reach of children and pets, and not where food is stored.
  • Never transfer into empty food storage containers such as soft drink bottles or water bottles. Moving the substance into a different container means you’ll also lose the safety information printed on the label, which can include emergency numbers and important first aid information.
  • Keep children and pets away from areas where insecticides are being used. Never eat or drink when applying the insecticide. Wash hands and face thoroughly before eating or drinking.
  • Do not smoke while working as it may increase the chances of the product being ingested. Ensure sprays and automatic dispensers are used in well ventilated areas.
  • Use the least amount of spray possible, as all are toxic and can cause harm if used incorrectly.
Common questions about synthetic pyrethroids Plus

How can I send the EPA some information about synthetic pyrethroids?

A call for information is now open. You can provide feedback on how the products are used, the benefits associated with these products, manufacture and import volumes, any scientific and technical information, and any alternatives to these products.

Read about the call for information

How do I know if my product contains synthetic pyrethroids?

The active ingredient is always listed on the label of fly sprays and household insecticides. You can check this to find out if it contains one of these synthetic pyrethroids:

  • Bifenthrin
  • Bioresmethrin
  • Cyfluthrin
  • Cyhalothrin
  • Cyhalothrin, lambda
  • Cypermethrin
  • Cypermethrin, alpha
  • Deltamethrin
  • Fenvalerate
  • Permethrin
  • Tetramethrin

Why is the EPA taking a further look at synthetic pyrethroids?

Nine of these synthetic pyrethroids are on the priority chemical list and science-based evidence, research and understanding about chemicals increases every day. The latest information indicates these chemicals on our priority list require further review and scrutiny, to ensure any risks to people and the environment continue to be managed effectively.

What is a reassessment?

Reassessment is the formal legal process for us to evaluate any new information, and take action to prevent, manage, mitigate or reduce risks that may have come to light since an approval was first granted. The process is a two-step one.

Learn more about chemical reassessments