Proposed Registration Decision PRD2022-12, Attenuated Cucumber green mottle mosaic virus strain ON-BM3; Al- Bio10 and Cuc-GUARD

Pest Management Regulatory Agency
15 September 2022
ISSN: 1925-0886 (PDF version)
Catalogue number: H113-9/2022-12E-PDF (PDF version)

Table of contents

• Proposed registration decision for attenuated Cucumber green mottle mosaic virus strain ON-BM3; Al-Bio10
• What does Health Canada consider when making a registration decision?
• What is attenuated Cucumber green mottle mosaic virus strain ON-BM3; Al-Bio10?
• Health considerations
• Environmental considerations
• Value considerations
• Measures to minimize risk
• Next steps
• Other Information

Proposed registration decision for attenuated Cucumber green mottle mosaic virus strain ON-BM3; Al-Bio10

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 Attenuated CGMMV strain ON-BM3; Al-Bio10 Technical and Cuc-GUARD, containing the technical grade active ingredient attenuated Cucumber green mottle mosaic virus (CGMMV) strain ON-BM3; Al-Bio10, to protect cucumber plants from virulent forms of CGMMV.

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 Overview describes the key points of the evaluation, while the Science Evaluation of Proposed Registration Decision PRD2022-12, Attenuated Cucumber green mottle mosaic virus strain ON-BM3; Al-Bio10 and Cuc-GUARD provides detailed technical information on the human health, environmental and value assessments of attenuated CGMMV strain ON-BM3; Al-Bio10 and Cuc-GUARD.

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^{Footnote 1} 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^{Footnote 2} 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 attenuated CGMMV strain ON-BM3; Al-Bio10 and Cuc-GUARD, Health Canada's PMRA will consider any comments received from the public in response to this consultation document.^{Footnote 3} Health Canada will then publish a Registration Decision^{Footnote 4} on attenuated CGMMV strain ON-BM3; Al-Bio10 and Cuc-GUARD, 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 PRD2022-12.

What is attenuated Cucumber green mottle mosaic virus strain ON-BM3; Al-Bio10?

Attenuated CGMMV strain ON-BM3; Al-Bio10 is a modified form of CGMMV. This modified strain protects greenhouse cucumbers against aggressive forms of the virus through cross-protection, which is a plant defense mechanism against viral infection.

Health considerations

Can approved uses of attenuated CGMMV strain ON-BM3; Al-Bio10 affect human health?

Attenuated CGMMV strain ON-BM3; Al-Bio10 is unlikely to affect your health when Cuc-GUARD is used according to the label directions.

Potential exposure to attenuated CGMMV strain ON-BM3; Al-Bio10 may occur when handling and applying Cuc-GUARD. When assessing health risks, several key factors are considered:

• the microorganism's biological properties (for example, infection cycle);
• reports of any adverse incidents;
• its potential to cause disease or toxicity; and
• the level to which people may be exposed relative to exposures already encountered in nature to other isolates of this microorganism.

The 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 that are determined as having no health risks of concern are considered acceptable for registration.

Waiver rationales supported by published scientific literature were submitted in lieu of toxicity and pathogenicity testing. Attenuated CGMMV strain ON-BM3; Al-Bio10 Technical and Cuc-GUARD are considered to be of low toxicity via the oral, pulmonary, and dermal routes and the microbial pest control agent (MPCA) is not considered infective or pathogenic. The end-use product and technical grade active ingredient are considered to be irritating to the eyes and skin, and are considered potential sensitizers.

Residues in water and food

Dietary risks from food and water are acceptable.

Residues of attenuated CGMMV strain ON-BM3; Al-Bio10 on treated crops are possible at the time of harvest. However, the technical grade active ingredient and end-use product are considered to be of low toxicity and the MPCA is not considered infective or pathogenic. In addition, the likelihood of attenuated CGMMV strain ON-BM3; Al-Bio10 contaminating drinking water is expected to be low as the label has the necessary mitigation measures to limit contamination of drinking water from the proposed uses of Cuc-GUARD. Consequently, dietary risks are acceptable for all segments of the population, including infants, children, adults and seniors.

Occupational risks from handling Cuc-GUARD

Occupational risks are acceptable when Cuc-GUARD is used according to label directions, which include protective measures.

Workers handling Cuc-GUARD can come into direct contact with attenuated CGMMV strain ON-BM3; Al-Bio10 on the skin, by inhalation, or in the eyes. To protect workers from exposure to Cuc-GUARD, the label states that workers must wear personal protective equipment, including long-sleeved shirt, long pants, protective eyewear (goggles), waterproof gloves, socks and shoes and a NIOSH-approved particulate filtering facepiece respirator with any N, R or P filter. The product label includes measures to restrict access to the treated area for 4 hours or until sprays have settled. The occupational risks are acceptable when the precautionary statements on the label are observed.

Risks in residential and other non-occupational environments

Estimated risk for non-occupational exposure is acceptable.

Cuc-GUARD is proposed for commercial use as a high-pressure spray in greenhouses only. Residential and non-occupational exposure to Cuc-GUARD is therefore expected to be low when label directions are observed. Consequently, the risk to residents and the general public is acceptable.

Environmental considerations

What happens when attenuated CGMMV strain ON-BM3; Al-Bio10 is introduced into the environment?

Environmental risks are acceptable.

Cucumber green mottle mosaic virus is a plant pathogen that causes disease in cucumber and other cucurbit crops. The virus belongs to the genus Tobamovirus in the family Virgaviridae. Since first described in 1935 in England, CGMMV has spread worldwide to other areas of Europe, Asia, Australia, Africa, and North America. Cucumber green mottle mosaic virus can spread readily by contact as its virions are stable and have been shown to remain infectious on contaminated surfaces for long periods.

Minimal environmental exposure to attenuated CGMMV strain ON-BM3; Al-Bio10 is expected following the proposed use in greenhouses.

Waiver rationales supported by published scientific literature were submitted in lieu of toxicity and pathogenicity testing on birds, wild mammals, fish, terrestrial and aquatic arthropods, honeybees, non-arthropod invertebrates, microorganisms, and terrestrial and aquatic plants. While the MPCA may be infective to certain non-target plants, it is not expected to cause significant disease in these plants. The technical grade active ingredient and end-use product are considered to be of low toxicity and not pathogenic or infective to other non-target organisms. Furthermore, exposure to outdoor environments is expected to be minimal since the use is restricted to greenhouses, therefore, significant adverse effects to non-target organisms are not expected.

Based on a critical review of data and published scientific literature submitted by the applicant, the risks to birds, wild mammals, fish, terrestrial and aquatic arthropods, honeybees, non-arthropod invertebrates, microorganisms, and terrestrial and aquatic plants are acceptable when Cuc-GUARD is applied according to directions on the label.

Value considerations

What is the value of Cuc-GUARD?

Cuc-GUARD protects greenhouse cucumbers against aggressive strains of CGMMV.

Cucumber green mottle mosaic virus is a pathogen that causes a serious disease of greenhouse-grown cucumbers. Cucumber green mottle mosaic virus is a relatively recent and rapidly spreading pathogen in Canada that results in reduced crop yield, quality and marketability. There are no products available to control this disease and growers rely on greenhouse sanitation practices to exclude the virus and prevent infection of cucumber plants. Cuc-GUARD is compatible with current greenhouse integrated pest management practices.

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 labels of Attenuated CGMMV strain ON-BM3; Al-Bio10 Technical and the end-use product, Cuc-GUARD to address the potential risks identified in this assessment are as follows.

Key risk-reduction measures – Human Health

The signal words 'POTENTIAL SENSITIZER', 'CAUTION EYE IRRITANT', and 'CAUTION SKIN IRRITANT' will appear on the primary display panel of the labels. Also, workers handling or applying Cuc-GUARD must wear a long-sleeved shirt, long pants, protective eyewear (goggles), waterproof gloves, socks and shoes and a NIOSH-approved particulate filtering facepiece respirator with any N, R or P filter.Furthermore, all unprotected workers are restricted from entering treated areas during application and for 4 hours following application or until sprays have settled.

Key risk-reduction measures – Environment

The end-use product label will include environmental precaution statements to reduce the potential for contamination of aquatic systems from the use of Cuc-GUARD.

Next steps

Before making a final registration decision on attenuated CGMMV strain ON-BM3; Al-Bio10 and Cuc-GUARD, Health Canada's PMRA will consider any comments received from the public in response to PRD2022-12. Health Canada will accept written comments on this proposal up to 45 days from the date of publication of PRD2022-12. 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 attenuated CGMMV strain ON-BM3; Al-Bio10 and Cuc-GUARD (based on the Science Evaluation of PRD2022-12). In addition, the test data referenced in this consultation document will be available for public inspection, upon application, in the PMRA's Reading Room. For more information, please contact the PMRA's Pest Management Information Service.