Proposed Registration Decision PRD2020-08, Pydiflumetofen and Saltro

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The online consultation is now closed.

Pest Management Regulatory Agency
15 June 2020
ISSN: 1925-0886 (PDF version)
Catalogue number: H113-9/2020-8E-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 Registration Decision PRD2020-08, Pydiflumetofen and Saltro please contact our publications office.

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

Summary

Table of Contents

Proposed registration decision for pydiflumetofen

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 Pydiflumetofen Technical and Saltro, containing the technical grade active ingredient pydiflumetofen, as a seed treatment fungicide to suppress seed-borne blackleg on rapeseed, including canola (Crop Subgroup 20A) and to control early season infection by Fusarium virguliforme on soybean.

Pydiflumetofen is currently registered as a foliar treatment on various field food and feed crops, greenhouse food and non-food crops, outdoor ornamentals and turf for the control and suppression of certain diseases. For details, see Proposed Registration Decision PRD2018-06, Pydiflumetofen, and Registration Decision RD2018-08, Pydiflumetofen.

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 PRD2020-08, Pydiflumetofen and Saltro provides detailed technical information on the human health, environmental and value assessments of pydiflumetofen and Saltro.

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:

Before making a final registration decision on pydiflumetofen and Saltro, Health Canada’s PMRA will consider any comments received from the public in response to PRD2020-08. Health Canada will then publish a Registration Decision on pydiflumetofen and Saltro, 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 PRD2020-08.

What is pydiflumetofen?

Pydiflumetofen is a broad-spectrum fungicide that is registered in Canada in several end-use products as the lone active ingredient or pre-mixed with other active ingredients. These products are applied as foliar treatments on various crops, ornamentals and turf grass to control or suppress certain diseases. Pydiflumetofen inhibits spore germination, mycelial growth and sporulation of the fungus on the leaf surface. The current application is for seed treatment use in rapeseed, including canola (Crop Subgroup 20A) and soybean.

Health considerations

Can approved uses of pydiflumetofen affect human health?

Saltro, containing pydiflumetofen, is unlikely to affect your health when used according to proposed label directions.

Potential exposure to pydiflumetofen may occur through the diet (food and drinking water), when handling and applying the end-use products, or when handling and planting treated seeds. When assessing health risks, two key factors are considered:

The dose levels used to assess risks are selected 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 dose levels 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, pydiflumetofen was of low acute toxicity by the oral, dermal, and inhalation routes of exposure. Pydiflumetofen was minimally irritating to the eyes and non-irritating to the skin. It did not cause an allergic skin reaction.

The acute toxicity of the end-use product Saltro containing pydiflumetofen, was low via the oral route of exposure and assumed to be low via the dermal route based on the results of the oral study. Saltro was of slight toxicity via the inhalation route of exposure; consequently, the signal word and hazard statement “CAUTION – POISON” are required on the label. It was non‑irritating to the eyes and skin, and did not cause an allergic skin reaction.

Registrant-supplied short- and long-term (lifetime) animal toxicity tests were assessed for the potential of pydiflumetofen to cause neurotoxicity, chronic toxicity, cancer, reproductive and developmental toxicity, genetic damage, and various other effects. The most sensitive endpoints for risk assessment were effects on body weight, liver, activity level, and behaviour. There was no evidence that pydiflumetofen damaged genetic material; however, it did cause liver tumours in mice. There was some evidence that the young animal was more sensitive to pydiflumetofen than the adult animal. The risk assessment protects against these and any other potential effects by ensuring that the level of exposure to humans is well below the lowest dose level at which these effects occurred in animal tests.

Residues in water and food

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

Acute dietary (food plus drinking water) intake estimates for the general population and all population subgroups were less than 8.5% of the acute reference dose, and are not of health concern. The highest exposed subpopulation was children 3–5 years old.

Aggregate dietary intake estimates (food plus drinking water) revealed that the general population and children (1–2 years old), the subpopulation which would ingest the most pydiflumetofen relative to body weight, are expected to be exposed to less than 30% of the acceptable daily intake. Based on these estimates, the chronic (cancer and non-cancer) dietary risk from pydiflumetofen is not of concern for all population sub-groups.

The Food and Drugs Act prohibits the sale of adulterated food, that is, food containing a pesticide residue that exceeds the established maximum residue limit (MRL). Pesticide MRLs are established for Food and Drugs Act purposes through the evaluation of scientific data under the Pest Control Products Act. Food containing a pesticide residue at the established MRL does not pose an unacceptable health risk.

Residue trials conducted throughout Canada and the United States using pydiflumetofen on soybeans and rapeseed (Crop Subgroup 20A) are acceptable. No changes are required to the established pydiflumetofen MRLs regulated under the Pest Control Products Act based on the review of the data.

Risks in residential and other non-occupational environments

A residential assessment was not required since these products are not permitted for use by residential handlers or for use in residential areas.

Occupational risks from handling Saltro

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

Workers in commercial seed treatment facilities, mobile treaters, on-farm treaters and planters and those planting and handling seed treated with Saltro can come into direct contact with pydiflumetofen through residues on the skin and through inhalation. Therefore, workers treating seeds in commercial seed treatment facilities or mobile treaters must use a closed-transfer system only, including closed mixing, loading, calibrating and closed treatment equipment. Workers cleaning or repairing seed treatment equipment must wear chemical-resistant coveralls over a long-sleeved shirt, long pants, chemical-resistant gloves, socks, chemical-resistant footwear and a dust mask. All other workers in a seed treatment facility must wear coveralls over a long-sleeved shirt, long pants, chemical-resistant gloves, socks, shoes and a dust mask. Workers completing on-farm seed treatment must wear a long-sleeved shirt, long pants, chemical-resistant gloves, socks and shoes. Workers planting treated seed must wear a long-sleeved shirt, long pants, chemical-resistant gloves, shoes and socks. Closed-cab planting is required for soybean seed.

For bystanders, exposure is expected to be much less than that for workers and is considered negligible. Therefore, health risks to bystanders are not of concern.

Environmental considerations

What happens when pydiflumetofen is introduced into the environment?

When pydiflumetofen is used according to the label directions, the risks to the environment are acceptable.

Pydiflumetofen can enter the environment when it is applied as a fungicide seed treatment product to control or suppress plant diseases. Birds and mammals may be exposed to pydiflumetofen when consuming treated seeds, while bees may be exposed to dust generated during the seeding process. When pydiflumetofen is used according to the label directions as a seed treatment on soybean and all crops within Crop Subgroup 20A, including canola, the risk to pollinators and birds are acceptable.

Pydiflumetofen applied as a seed treatment may pose a risk to non-target wild mammals. As such, the label will require a precautionary statement about the risk to wild mammals and that spilled and exposed seeds must be incorporated into the soil or cleaned up from the soil surface.

Value considerations

What is the value of Saltro?

Saltro will provide Canadian users with a new mode of action on rapeseed, including canola (Crop Subgroup 20A) and a new product on soybean to manage two important diseases.

Saltro is effective for suppressing seed-borne blackleg on rapeseed, including canola (Crop Subgroup 20A) and for controlling early season infection by Fusarium virguliforme (the pathogen of sudden death syndrome) on soybean.

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 Pydiflumetofen Technical and Saltro to address the potential risks identified in this assessment are as follows.

Key risk-reduction measures

Human health

As there can be direct contact with pydiflumetofen on the skin or through inhalation of dust, workers treating seed with pydiflumetofen in commercial facilities (including mobile treaters) or performing clean-up and repair activities must wear chemical-resistant coveralls over a long-sleeved shirt, long pants, chemical-resistant gloves, socks, and chemical-resistant footwear and a dust mask. Workers bagging, sewing or stacking seed treated with pydiflumetofen in commercial facilities must wear coveralls over a long-sleeved shirt, long pants, chemical-resistant gloves, socks, and shoes and a dust mask. On-farm treaters and planters must wear a long-sleeved shirt, long pants, shoes, socks and chemical-resistant gloves. Furthermore, commercial seed treatment is restricted to closed-transfer systems. Closed-cab tractors for planting soybean seed are required.

Environment

Standard label statements are required to inform users of the toxicity of pydiflumetofen to wild mammals.

Standard statements on the label and the treated seed tags are required to inform users that spilled or exposed seeds must be incorporated into the soil or cleaned up from soil surface.

Next steps

Before making a final registration decision on pydiflumetofen and Saltro, Health Canada’s PMRA will consider any comments received from the public in response to PRD2020-08. Health Canada will accept written comments on this proposal (PRD2020-08) up to 45 days from the date of its publication. Please forward all comments to PMRA 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 Pydiflumetofen and Saltro (based on the Science Evaluation of PRD2020-08). In addition, the test data referenced in PRD2020-08 will be available for public inspection, upon application, in the PMRA’s Reading Room (located in Ottawa).

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