Proposed Registration Decision PRD2020-09, Fluxapyroxad and Xzemplar

Pest Management Regulatory Agency
18 June 2020
ISSN: 1925-0886 (PDF version)
Catalogue number: H113-9/2020-9E-PDF (PDF version)

Summary

Table of Contents

• Proposed registration decision for fluxapyroxad
• What does Health Canada consider when making a registration decision?
• What is fluxapyroxad?
• Health considerations
• Environmental considerations
• Value considerations
• Measures to minimize risk
• Next steps
• Other information

Proposed registration decision for fluxapyroxad

Health Canada’s Pest Management Regulatory Agency (PMRA), under the authority of the Pest Control Products Act, is proposing registration for the sale and use of Xemium Technical Fungicide and Xzemplar, containing the technical grade active ingredient fluxapyroxad, to control dollar spot on golf course turf grass.

Fluxapyroxad is currently registered to control or supress various fungal diseases in numerous crops. For details, see Proposed Registration Decision PRD2012-09, Fluxapyroxad and Registration Decision RD2012-31, Fluxapyroxad.

An evaluation of available scientific information found that, under the approved conditions of use, the health and environmental risks and the value of the pest control products are acceptable.

This summary describes the key points of the evaluation, while the Science Evaluation of Proposed Registration Decision PRD2020-09, Fluxapyroxad and Xzemplar provides detailed technical information on the human health, environmental and value assessments of fluxapyroxad and Xzemplar.

What does Health Canada consider when making a registration decision?

The key objective of the Pest Control Products Act is to prevent unacceptable risks to people and the environment from the use of pest control products. Health or environmental risk is considered acceptable if there is reasonable certainty that no harm to human health, future generations or the environment will result from use or exposure to the product under its proposed conditions of registration. The Act also requires that products have value when used according to the label directions. Conditions of registration may include special precautionary measures on the product label to further reduce risk.

To reach its decisions, the PMRA applies modern, rigorous risk-assessment methods and policies. These methods consider the unique characteristics of sensitive subpopulations in humans (for example, children) as well as organisms in the environment. These methods and policies also consider the nature of the effects observed and the uncertainties when predicting the impact of pesticides. For more information please refer to the following:

• Protecting Your Health and the Environment
• Pesticide Registration Process
• Pesticide Risk Reduction Program.

Before making a final registration decision on fluxapyroxad and Xzemplar, Health Canada’s PMRA will consider any comments received from the public in response to PRD2020-09. Health Canada will then publish a Registration Decision on fluxapyroxad and Xzemplar, which will include the decision, the reasons for it, a summary of comments received on the proposed registration decision and Health Canada’s response to these comments.

For more details on the information presented in this summary, please refer to the Science Evaluation of PRD2020-09.

What is fluxapyroxad?

Fluxapyroxad is a broad-spectrum fungicide registered for use on various crops. It inhibits spore germination, mycelial growth, and sporulation of the fungus on the leaf surface. The current application is for disease management in golf course turf grass.

Health considerations

Can approved uses of fluxapyroxad affect human health?

Xzemplar, containing fluxapyroxad, is unlikely to affect your health when used according to label directions.

Potential exposure to fluxapyroxad may occur through the diet (drinking water), when handling and applying the end-use product, or when coming into contact with treated turf. 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 level at which 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 pesticide products are used according to label directions.

In laboratory animals, the technical grade active ingredient fluxapyroxad was of low acute toxicity by the oral, dermal and inhalation routes of exposure. Fluxapyroxad was non-irritating to the eyes and minimally irritating to the skin, and did not elicit an allergic skin reaction.

The acute toxicity of the end-use product Xzemplar, containing fluxapyroxad, was considered to be low via the oral, dermal and inhalation routes of exposure. It was minimally irritating to the skin, non-irritating to eyes and did not cause an allergic skin reaction.

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 fluxapyroxad to cause neurotoxicity, immunotoxicity, chronic toxicity, cancer, reproductive and developmental toxicity, and various other effects. The most sensitive endpoints for risk assessment were effects on body weight and changes to the liver and thyroid. Fluxapyroxad produced liver and thyroid tumours in rats. There was sufficient information available to determine that a threshold-based cancer risk assessment was appropriate. There was no evidence of increased sensitivity of the young compared to adult animals. The risk assessment protects against the effects noted above and other potential effects by ensuring that the level of exposure to humans is well below the lowest dose at which these effects occurred in animal tests.

Residues in food and drinking water

Dietary risks from food and drinking water are not of health concern.

No food residue data are required to support the registration of fluxapyroxad for use in/on turf grass on golf courses in Canada. However, due to the potential for residues to enter drinking water sources as a result of the turf grass use, an aggregate dietary assessment was conducted to assess health risks from overall exposure to potential food residues from existing dietary uses and the current proposed use.

Aggregate acute dietary (food plus drinking water) intake estimates for the general population and all population subgroups are expected to be less than 13% of the acute reference dose, and are not of health concern.

Aggregate chronic (cancer and non-cancer) dietary (food plus drinking water) intake estimates for the general population and all population subgroups indicated that drinking water was the major contributor to the dietary exposure, however, based on the conservatism included in the drinking water modelling, this exposure is expected to be over-estimated and, therefore, not of health concern.

As no food residue data are required to support the registration of fluxapyroxad for use in/on turf grass on golf courses in Canada, maximum residue limits (MRLs) are not required for this proposed use. For more details concerning the MRLs for fluxapyroxad on various food commodities, please refer to the Maximum Residue Limit Database in the Pesticides section of Canada.ca

Occupational risks from handling Xzemplar

Occupational risks are not of concern when Xzemplar is used according to the label directions, which include protective measures.

Workers who mix, load or apply Xzemplar, as well as workers entering freshly treated golf courses, can come in direct contact with fluxapyroxad residues on the skin. Therefore, the label specifies that workers must wear a long-sleeved shirt, long pants, chemical-resistant gloves, shoes and socks during mixing, loading, application, clean-up and repair. The label also requires that workers and the general public do not enter treated areas in golf courses until sprays have dried. Taking into consideration these label statements, the number of applications and the expectation of the exposure period for handlers and workers, the health risks to these individuals are not of concern.

Risks in residential and other non-occupational environments

Residential and non-occupational risks are not of health concern when Xzemplar is used according to the label directions.

Adults, youth and children may be exposed to fluxapyroxad while golfing on courses treated with Xzemplar. Based on the expected short- to intermediate-term duration of this activity, the health risk to children, youth and adults is not a concern. There are no residential turf uses of Xzemplar.

Risks to bystanders

Bystander risks are not of health concern when Xzemplar is used according to the label directions and spray drift restrictions are observed.

A standard label statement to protect against drift during application is required on the label. Therefore, health risks to bystanders are not of concern.

Environmental considerations

What happens when fluxapyroxad is introduced into the environment?

When fluxapyroxad is used according to label directions, the risks to the environment are considered to be acceptable.

Fluxapyroxad enters the environment when it is used outdoors as a fungicide. Once in the environment, fluxapyroxad is slowly broken down by microbes found in soil and water. Two major transformation products are formed in soil, M700F001 and M700F002. Given their properties, fluxapyroxad and M700F002 may leach through soil. Fluxapyroxad could also reach surface water through spray drift and through the movement of soil particles in surface runoff. Once in water, fluxapyroxad is expected to move to the sediment. When fluxapyroxad is used in accordance with the label and the required precautions, the resulting environmental risk is considered to be acceptable.

Value considerations

What is the value of Xzemplar?

Fluxapyroxad is the active ingredient in Xzemplar. The registration of Xzemplar will provide Canadian users with a new product to manage dollar spot, an important fungal disease on golf course turf grass.

Xzemplar contains fluxapyroxad as its active ingredient. Xzemplar, applied as a foliar spray, is effective against dollar spot, an economically important fungal disease of cool-season turf grass on golf courses.

Measures to minimize risk

Labels of registered pesticide products include specific instructions for use. Directions include risk-reduction measures to protect human and environmental health. These directions must be followed by law.

The key risk-reduction measures being proposed on the label of Xemium Technical Fungicide and Xzemplar to address the potential risks identified in this assessment are as follows.

Key risk-reduction measures

Human health

Because there is a concern with users coming into direct contact with fluxapyroxad on the skin or through inhalation of spray mists, any users must wear a long-sleeved shirt, long pants, chemical-resistant gloves, shoes and socks during mixing, loading, application, clean-up and repair.

The Xzemplar label also requires that workers and the general public do not enter treated areas in golf courses until sprays have dried. In addition, standard label statements to protect against drift during application are present on the label.

Environment

To protect the environment, the following proposed risk mitigation measures are required:

• Spray buffer zones of 1 metre for the protection of sensitive aquatic and terrestrial habitats.
• A statement indicating that fluxapyroxad may leach in soil.
• Advisory statements informing users of potential risk to non-target terrestrial plants and aquatic organisms.
• Recommendations to reduce runoff to further protect the aquatic environment.

Next steps

Before making a final registration decision on fluxapyroxad and Xzemplar, Health Canada’s PMRA will consider any comments received from the public in response to PRD2020-09. Health Canada will accept written comments on PRD2020-09 up to 45 days from the date of publication of this document. Please forward all comments to Publications. Health Canada will then publish a Registration Decision, which will include its decision, the reasons for it, a summary of comments received on the proposed decision and Health Canada’s response to these comments.

Other information

When the Health Canada makes its registration decision, it will publish a Registration Decision on fluxapyroxad and Xzemplar (based on the Science Evaluation of PRD2020-09). In addition, the test data referenced in PRD2020-09 will be available for public inspection, upon application, in the PMRA’s Reading Room (located in Ottawa).