Proposed Re-evaluation Decision PRVD2017-06, Amitraz

Notice to the reader:

The online consultation is now closed.

Pest Management Regulatory Agency
30 June 2017
ISSN: 1925-0967 (PDF version)
Catalogue number: H113-27/2017-6E-PDF (PDF version)

This page is a summary of the consultation document. If you would like to comment, please request the full consultation document.

To obtain a full copy of Proposed Re-evaluation Decision PRVD2017-06, Amitraz please contact our publications office.

Should you require further information please contact the Pest Management Information Service.

Summary

Table of Contents

Executive Summary

Health Canada's Pest Management Regulatory Agency (PMRA)

Health Canada's primary objective in regulating pesticides is to protect Canadians' health and their environment. Pesticides must be registered by Health Canada's Pest Management Regulatory Agency before they can be imported, sold, or used in Canada. Pesticides must go through rigorous science-based assessments before being approved for sale in Canada.

All registered pesticides must be re-evaluated by the PMRA on a cyclical basis to make sure they continue to meet modern health and environment safety standards and continue to have value. This may happen even sooner if there have been changes in the required information or to the risk assessment methodology. Re-evaluations may result in:

  • changes to how products are used;
  • changes to product labels to meet current health and environmental standards; or,
  • removing products from the market to prevent future harm to health or the environment.

Re-evaluation of Amitraz for Pet Collar Use

Amitraz is an acaricide/insecticide registered to control American and brown dog ticks on dogs which are older than 12 weeks of age and with a neck size of up to 62 cm, in a slow release pet collar.

When conducting the re-evaluation of amitraz for pet collar use, the PMRA reviewed scientific information provided by pesticide manufacturers, as well as published scientific information. For the human health assessment, the following exposure scenarios were examined: exposure when applying the collar and postapplication exposure from coming into contact with the pesticide after the collar has been applied. Due to the nature of this use (that is, pet collar use), a dietary and environmental assessment were not required.

Amitraz is also registered for control of Varroa mite in honey bee colonies. However, as this use was registered in 2012, the risk assessment for this use in honey bee colonies is considered up to date and, thus, is not considered in this re-evaluation.

Key Findings

The human health risk assessment found that there are risks of concern from postapplication exposure following contact with dogs wearing amitraz-impregnated pet collars. Therefore, the cancellation of the use of amitraz in pet collars is proposed at this time.

Next Steps

The proposed re-evaluation decision is now open for public consultation for 90 days from the date of Proposed Re-evaluation Decision PRVD2017-06, Amitraz. PMRA is inviting the public to submit comments on the proposed re-evaluation decision for amitraz for use in pet collars, including proposals that may refine the risk assessment and risk management. Once PMRA considers the comments and any information that are received during the public consultation period, it will publish a final decision.

Overview

What is the Proposed Re-evaluation Decision for Amitraz Used in Pet Collars?

The evaluation determined that under the current conditions of use, the human health risks for pet collars containing amitraz do not meet current safety standards. Therefore, the PMRA is proposing to cancel the use of amitraz in pet collars.

Before making a final re-evaluation decision on the use of amitraz in pet collars, the PMRA will accept and consider written comments on Proposed Re-evaluation Decision PRVD2017-06, Amitraz received up to 90 days from the date of PRVD2017-06, Amitraz. Please forward all comments to Publications. The PMRA will consider any additional data/information submitted during the consultation period in the final decision.

What Does Health Canada Consider When Making a Re-evaluation Decision?

Under the Pest Control Products Act, all registered pesticides must be re-evaluated by the PMRA on a cyclical basis to make sure they continue to meet modern health and environmental safety standards and continue to have value. The re-evaluation considers data from pesticide manufacturers, published scientific reports, information from other regulatory agencies and other available, relevant information. To reach its decisions, the PMRA applies internationally accepted hazard and risk assessment methods and modern risk management approaches and policies.

For more information on how the PMRA regulates pesticides, as well as the assessment process, please visit the Pesticides and Pest Management portion of Health Canada's website.

What Is Amitraz?

Amitraz is an acaricide/insecticide currently registered for control of American and brown dog ticks on dogs that are older than 12 weeks of age and with a neck size of up to 62 cm, in a slow release pet collar. It is also registered for the control of Varroa mite in honey bee colonies.

Health Considerations

Can Approved Uses of Amitraz in Pet Collars Affect Human Health?

Risk concerns were identified for the product Preventic Tick Collar for Dogs, containing amitraz, when used according to label directions.

Potential exposure to amitraz may occur when handling and applying this collar, or when coming into contact with dogs wearing the collar. When assessing health risks, two key factors are considered:

  • the levels where no health effects occur and
  • the levels to which people may be exposed.

The dose levels used to assess risks are established to protect the most sensitive human population (for example, children and nursing mothers). As such, sex and gender are taken into account in the risk assessment. Only uses for which the exposure is well below levels that cause no effects in animal testing are considered acceptable for registration.

Toxicology studies in laboratory animals describe potential health effects from varying levels of exposure to a chemical and identify the dose where no effects are observed. The health effects noted in animals occur at doses more than 100-times higher (and often much higher) than levels to which humans are normally exposed when using pesticide products according to label directions.

In laboratory animals, the acute oral toxicity of the active ingredient amitraz varied widely among species, ranging from low to high toxicity. Amitraz was slightly acutely toxic via the dermal route, of low toxicity via the inhalation route, minimally irritating to the eyes and skin, and caused an allergic skin reaction. Consequently, following consultation on the proposed decision, if amitraz is deemed acceptable for continued registration in dog collars, the following signal words and hazard statements “DANGER POISON” and “POTENTIAL SKIN SENSITIZER” would be required on the label for this active ingredient.

Preventic Tick Collar for Dogs was of low acute toxicity via the oral and dermal routes, non-irritating to the skin, and did not cause an allergic skin reaction in laboratory animals. Based on the physical form of the product, which is a plastic collar impregnated with amitraz, it is not considered to pose an acute inhalation or an eye irritation hazard. With regards to safety to dogs wearing Preventic Tick Collar for Dogs, the level of concern was low on the basis of an overall assessment, which included a study in dogs wearing collars under conditions that simulated exaggerated exposure to amitraz.

Registrant-supplied short, and long term (lifetime) animal toxicity tests, as well as information from the published scientific literature, were assessed for the potential of amitraz to cause neurotoxicity, immunotoxicity, chronic toxicity, cancer, reproductive and developmental toxicity, and various other effects. The most sensitive endpoint used for risk assessment consisted of effects on the nervous system. There was evidence of sensitivity of the young animal compared to adult animals in the available studies. Information was lacking to adequately assess effects on the nervous system of the young. The risk assessment takes the above noted information into account in determining the allowable level of human exposure to amitraz.

Risks in Residential and Other Non-Occupational Environments

Residential risks of concern were identified for use of the Preventic Tick Collar for Dogs.

Exposure to amitraz can occur when adults handle the Preventic Tick Collar for Dogs and come in direct contact with amitraz residues on the skin. Adults, youth, and children can come in direct contact with amitraz residues on the skin when contacting treated pets. In addition, children can ingest residues by hand-to-mouth activity after contacting treated dogs.

Concern was identified for adults, youth, and children who come into contact with dogs wearing the Preventic Tick Collar for Dogs.

Environmental Considerations

The use of amitraz in dog collars does not pose a risk to the environment as environmental exposure is expected to be negligible.

Value Considerations

Amitraz for use in pest collars is registered to control American and brown dog ticks on dogs. Many ticks are known as vector-borne disease and products, such as pet collars, are one of the ways to help protect dogs from ticks. In addition, veterinary drugs are also available for control of ticks on dogs.

Proposed Measures to Minimize Risk

The PMRA has assessed the available information and concluded that the use of amitraz in pet collars and the associated end-use product used in accordance with the label poses potential risks of concern to human health. Specifically, potential health risk concerns were identified from postapplication exposure to amitraz. Therefore, the PMRA is proposing to cancel the use of amitraz in pet collars in Canada.

What Additional Scientific Information Is Requested?

As the PMRA is proposing cancellation of pet collar uses of amitraz, no additional data will be required.

Next Steps

During the consultation period, registrants and stakeholder organizations may submit further data that could be used to refine risk assessments (exposure or use information), which could result in revised risk-reduction measures. Stakeholders who are planning to provide information of this type are advised to contact the PMRA early in the consultation period, for advice on studies or information that could be submitted to help refine the relevant risk assessments.

Before making a final re-evaluation decision on amitraz, the PMRA will consider any comments received from the public in response to Proposed Re-evaluation Decision PRVD2017-06, Amitraz. The PMRA will then publish a Re-evaluation Decision that will include the decision, the reasons for it, a summary of comments received on the proposed decision and the PMRA's response to these comments.

Page details

Date modified: