Proposed Registration Decision PRD2024-05, Lymantria dispar multicapsid nucleopolyhedrovirus strain LDP-67 and BoVir

Pest Management Regulatory Agency
29 April 2024
ISSN: 1925-0886 (PDF version)
Catalogue number: H113-9/2024-5E-PDF (PDF version)

Summary

Table of contents

• Proposed registration decision for Lymantria dispar multicapsid nucleopolyhedrovirus strain LDP-67
• What does Health Canada consider when making a registration decision?
• What is Lymantria dispar multicapsid nucleopolyhedrovirus?
• Health considerations
• Environmental considerations
• Value considerations
• Measures to minimize risk
• Next steps
• Other information

Proposed registration decision for Lymantria dispar multicapsid nucleopolyhedrovirus strain LDP-67

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 Disparvirus Technical and BoVir, containing the active ingredient Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67, to suppress spongy moth (Lymantria dispar) in residential areas.

Lymantria dispar multicapsid nucleopolyhedrovirus is currently registered for suppression of spongy moth (formerly referred to as gypsy moth) (Lymantria dispar) in forests and woodlots. For details, see Proposed Re-evaluation Decision PRVD2013-02, Nucleopolyhedrovirus for Gypsy Moth Larvae, and Re-evaluation Decision RVD2014-07, Nucleopolyhedrovirus for Gypsy Moth Larvae.

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 PRD2024-05, Lymantria dispar multicapsid nucleopolyhedrovirus strain LDP-67 and BoVir provides detailed technical information on the human health, environmental and value assessments of Lymantria dispar multicapsid nucleopolyhedrovirus strain LDP-67 and BoVir.

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 individuals 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 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). They also consider the unique characteristics of 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 on how the Health Canada regulates pesticides, the assessment process and risk-reduction programs, please visit the Pesticides and pest management section of the Canada.ca website.

Before making a final registration decision on Lymantria dispar multicapsid nucleopolyhedrovirus strain LDP-67 and BoVir, Health Canada's PMRA will consider any written comments received from the public in response to this consultation document.^{Footnote 3} Health Canada will then publish a Registration Decision^{Footnote 4} on Lymantria dispar multicapsid nucleopolyhedrovirus strain LDP-67 and BoVir, 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 the full version of PRD2024-05.

What is Lymantria dispar multicapsid nucleopolyhedrovirus?

Lymantria dispar multicapsid nucleopolyhedrovirus is a baculovirus. Viruses in family Baculoviridae infect only arthropods and normally kill their hosts. Lymantria dispar multicapsid nucleopolyhedrovirus is specific to the spongy moth (Lymantria dispar) and is the active ingredient in the end-use product, BoVir. BoVir is proposed for application to trees growing in residential areas such as parks, boulevards and other recreational greenspaces, which collectively is referred to as the urban forest.

Health considerations

Can approved uses of Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67 Affect Human Health?

Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67 is unlikely to affect your health when BoVir is used according to the label directions.

Potential exposure to Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67 may occur when handling and applying BoVir. 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 as determined in toxicological studies; 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.

Studies in laboratory animals describe potential health effects from large doses of exposure to a microorganism and identify any pathogenicity, infectivity and toxicity concerns.

When other baculoviruses were tested on laboratory animals and in tissue cultures, there were no signs of significant toxicity or disease. Furthermore, there have been no reported adverse effects despite the natural occurrence and prevalence of baculoviruses in the environment, and the limited host range associated with baculoviruses has been well documented. Disparvirus Technical is expected to be of low toxicity by the oral, pulmonary and dermal routes of exposure and is not a dermal irritant. The available information indicates that the MPCA is not infective or pathogenic. BoVir is of low toxicity by the oral, inhalation and dermal routes and is not a dermal irritant.

In the absence of eye irritation testing, the technical grade active ingredient and end-use product are assumed to be eye irritants.

All microorganisms, including Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67, contain substances that are potential sensitizers and thus, sensitivity may possibly develop in individuals exposed to potentially large quantities of Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67.

Residues in water and food

Dietary risks from food and water are acceptable.

No dietary exposure is anticipated from agricultural commodities as no food uses are proposed. In addition, the likelihood of residues of Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67 contaminating drinking water supplies is expected to be low as the label has the necessary mitigation measures to limit contamination of drinking water from the proposed residential uses of BoVir. Consequently, health risks from dietary exposure are acceptable for all segments of the population, including infants, children, adults and seniors.

Occupational risks from handling BoVir

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

The application methods, rates and frequency proposed for BoVir are consistent with the currently registered use pattern and are not expected to result in an increase in occupational exposure.

Workers handling BoVir can be exposed to Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67 through direct skin or eye contact or through inhalation. To protect workers from exposure to BoVir, the label states that workers must wear personal protective equipment, including a long-sleeved shirt, long pants, protective eyewear (goggles), waterproof gloves, socks and shoes, and a NIOSH-approved particulate filtering facepiece respirator with any R or P filter. The product label includes measures to restrict access to the treated area for four hours or until sprays have dried.

The health risks to workers 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.

BoVir is proposed for commercial and restricted use in residential areas such as urban forests (for example, parks). The label includes directions to reduce spray drift, and persons are not permitted to enter treated areas for four hours or until sprays have dried. Residential and non-occupational exposure to BoVir is, however, expected to be low when the label directions are observed. Consequently, the health risk to residents and the general public is acceptable.

Environmental considerations

What happens when Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67 is introduced into the environment?

Environmental risks are acceptable.

Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67 is a naturally occurring baculovirus that specifically infects lepidopteran insects. Baculoviruses are common and persistent in aquatic and terrestrial ecosystems. BoVir is proposed for use as an insecticide to supress spongy moth populations on trees in residential areas and is not intended for aquatic applications. The use of BoVir in residential areas is not expected to result in sustained increases of Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV) strain LDP-67 in terrestrial and aquatic environments beyond natural background levels.

Based on a critical review of animal studies, scientific rationales and information from public sources, no significant effects to birds, wild mammals, fish, terrestrial and aquatic non-target arthropods, and plants are expected when BoVir is applied according to directions on the label.

Value considerations

What is the value of BoVir?

BoVir is a pest control product that only affects the spongy moth.

Spongy moth can be a very serious pest of many different species of trees, especially oak trees, anywhere in the landscape. Because its active ingredient is specific to the spongy moth, BoVir can help manage this pest without affecting any non-target species.

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 Disparvirus Technical and BoVir to address the potential risks identified in this assessment are as follows.

Key risk-reduction measures – Human health

The signal words "POTENTIAL SENSITIZER" and "CAUTION EYE IRRITANT" appear on the primary display panel of the labels.

The end-use product and technical grade active ingredient are considered potential sensitizers. In turn, workers handling or applying BoVir 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 R or P filter. Furthermore, all unprotected workers or persons are restricted from entering treated areas during application and for four hours following application or until sprays have dried.

Key risk-reduction measures – Environment

The end-use product label will include environmental precautionary statements to reduce runoff and contamination of aquatic systems from the use of BoVir.

Next steps

Before making a final registration decision on Lymantria dispar multicapsid nucleopolyhedrovirus strain LDP-67 and BoVir, Health Canada's PMRA will consider any written comments received from the public in response to PRD2024-05 up to 45 days from the date of publication (29 April 2024) of PRD2024-05. 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 Lymantria dispar multicapsid nucleopolyhedrovirus strain LDP-67 and BoVir (based on the Science Evaluation of PRD2024-05). 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.