Proposed Registration Decision PRD2026-07, AQUABAC II XT Biological Larvicide, containing Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144

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• Health Canada
• Healthy Environments and Consumer Safety Branch
• Pesticides Regulatory Directorate
• 20 April 2026
• ISSN: 1925-0886 (PDF version)
• Catalogue number: H113-9/2026-7E-PDF (PDF version)

Summary

Table of contents

• Proposed Registration Decision for Bacilllus thuringiensis israelensis serotype H-14, strain BMP-144
• What does Health Canada consider when making a registration decision?
• What is Bacillus thuringiensis subspecies israelensis, serotype H-14, strain BMP-144?
• Health considerations
• Environmental considerations
• Value considerations
• Measures to minimize risk
• Next steps
• Other information

Proposed Registration Decision for Bacilllus thuringiensis subsp. israelensis serotype H-14, strain BMP-144

Health Canada, pursuant to subsection 28(1) of the Pest Control Products Act, is proposing registration for the sale and use of AQUABAC II XT Biological Larvicide, containing Bacilllus thuringiensis subsp. israelensis serotype H-14, strain BMP-144, to control fungus gnats on greenhouse ornamentals (use-site category 6 – Greenhouse Non-Food). This evaluation was completed under the User Requested Minor Use Label Expansion program, which is a cooperative program between Agriculture and Agri-Food Canada and Health Canada and includes participation by sponsor groups, manufacturers, and both provincial and federal governments.

Bacilllus thuringiensis subsp. israelensis serotype H-14, strain BMP-144 is a microbial pest control agent (MPCA) registered against mosquito larvae in flood water, roadside ditches, storm water retention areas, etc., under use-site category 2 – Aquatic Non-Food. For details, see the Proposed Acceptability for Continuing Registration PACR2006-09, Re-evaluation of Bacillus thuringiensis and Re-evaluation Decision RVD2008-18, Re-evaluation Decision Bacillus thuringiensis.

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 product is acceptable.

This summary describes the key points of the evaluation, while the Science evaluation of Proposed Registration Decision PRD2026-07, AQUABAC II XT Biological Larvicide, containing Bacillus thuringiensis subsp. Israelensis serotype H-14, strain BMP-144 provides detailed technical information on the human health, environmental and value assessments of AQUABAC II XT Biological Larvicide, containing Bacilllus thuringiensis subsp. israelensis serotype H-14, strain BMP-144.

What does Health Canada consider when making a registration decision?

The primary 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, Health Canada 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 Health Canada regulates pesticides, the assessment process and risk-reduction programs, please visit the Pesticides and pest management portion of Canada.ca.

Before making a final registration decision on AQUABAC II XT Biological Larvicide, containing Bacilllus thuringiensis subsp. israelensis serotype H-14, strain BMP-144, Health Canada will consider any written comments received from the public directly related to the proposed decision in this consultation document.^{Footnote 3} Health Canada will then publish a Registration Decision^{Footnote 4} on AQUABAC II XT Biological Larvicide, containing Bacilllus thuringiensis subsp. israelensis serotype H-14, strain BMP-144, 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 PRD2026-07.

What is Bacillus thuringiensis subspecies israelensis, serotype H-14, strain BMP-144?

Bacillus thuringiensis subspecies israelensis, serotype H-14, strain BMP-144 is a bacterium that can be found in soil. Bacillus thuringiensis bacteria disrupt the digestive system in larvae of certain kinds of insects, causing death. The subspecies israelensis is specific to larvae of flies (members of the insect order Diptera) and is often used to control biting flies such as mosquitoes and black flies.

Health considerations

Can approved uses of Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144 affect human health?

Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144 is unlikely to affect human health when AQUABAC II XT Biological Larvicide is used according to label directions.

Potential exposure to Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144 may occur when handling and applying AQUABAC II XT Biological Larvicide.

When assessing health risks, several key factors are considered:

• the microorganism's biological properties (for example, production of toxic byproducts);
• 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.

Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144 and AQUABAC II XT Biological Larvicide were first registered as pest control products in 1982 and in 2006, respectively. Health Canada re-evaluated the products and approved both for re-registration. At that time, Health Canada published Proposed Acceptability for Continuous Registration PACR2006-09, Bacillus thuringiensis.

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 Bacillus thuringiensis was tested on laboratory animals, there was low toxicity following oral, pulmonary and dermal exposures, and no infectivity following oral, pulmonary or intraperitoneal exposures. Furthermore, there was no sign that the MPCA, Bacillus thuringiensis, caused any disease.

All microorganisms, including Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144, contain substances that are potential sensitizers and thus, sensitivity may develop in individuals exposed to potentially large quantities of Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144.

The end-use product, AQUABAC II XT Biological Larvicide (PCP Reg. No. 27376), is of low acute toxicity via the oral, dermal and inhalation routes of exposure and is classified as an eye irritant, a skin irritant and a potential sensitizer. AQUABAC II XT Biological Larvicide does not contain any formulants of human health concern.

Residues in drinking water and food

Dietary risks from food and drinking water are acceptable.

AQUABAC II XT Biological Larvicide is not registered for food or feed uses and the proposed use expansion to greenhouse ornamentals does not include food crops.

Dietary exposure from 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 AQUABAC II XT Biological Larvicide. Health risks from residues of B. thuringiensis subsp. israelensis serotype H-14, strain BMP-144 in drinking water are acceptable due to the low toxicity/pathogenicity profile of Bacillus thuringiensis, and its limited exposure following applications of the end-use product.

Risks in residential and other non-occupational environments

Estimated risk for residential and other non-occupational exposure is acceptable.

AQUABAC II XT Biological Larvicide is registered as a commercial biological larvicide end-use product that is used to treat aquatic non-food areas for mosquitos. The new use will include treatment of greenhouse-grown ornamentals by soil drench for fungus gnats. There are no residential uses. The existing label includes measures to prevent bystander and residential exposure such as reducing spray drift. Residential and non-occupational exposure to AQUABAC II XT Biological Larvicide is expected to be low when label directions are observed.

Consequently, the health risk to residents and the general public is acceptable.

Occupational risks from handling AQUABAC II XT Biological Larvicide

Occupational risks are acceptable when AQUABAC II XT Biological Larvicide is used according to the label directions, which include protective measures.

Workers handling AQUABAC II XT Biological Larvicide can come into direct contact with Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144 through direct contact with skin or through inhalation when applying the product as a soil drench to greenhouse-grown ornamentals.

To protect workers from exposure to AQUABAC II XT Biological Larvicide when applied as a soil drench, the label states that workers must wear personal protective equipment, including a long-sleeved shirt, long pants, waterproof gloves, socks and shoes, and a NIOSH-approved particulate filtering facepiece respirator with any N, R or P filter. The label also includes measures to prevent exposure by reducing spray drift.

The proposed new use does not pose any additional occupational exposure concerns, therefore, the health risks to workers from the proposed use expansion are acceptable when the precautionary statements on the labels are observed.

Environmental considerations

What happens when Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144 is introduced into the environment?

Environmental risks are acceptable.

The proposed use expansion of Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144 to greenhouse ornamentals not expected to significantly increase environmental exposure to this microorganism.

As not all species of terrestrial arthropods have been directly assessed for effects at each life stage, the label will include a statement to mitigate the potential risk to beneficial arthropods which may be used in greenhouse IPM programs, as a best practice.

The label will also include a standard statement to manage greenhouse effluent.

Overall, the risks to the environment are acceptable.

Value considerations

What Is the Value of Aquabac II XT Biological Larvicide?

Aquabac II XT Biological Larvicide can control fungus gnats in greenhouse ornamentals.

In addition to its registered uses to control mosquito larvae, AQUABAC II XT Biological Larvicide can be applied as a soil drench on greenhouse-grown ornamentals to control larvae of fungus gnats. Fungus gnat larvae can damage the roots of plants and promote root rot, and emerging adults are a nuisance in retail stores and homes.

Measures to minimize risk

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

The key risk-reduction measures being proposed on the label of AQUABAC II XT Biological Larvicide to address the potential risks identified in this assessment are as follows.

Key risk-reduction measures - Human health

The signal words "CAUTION - EYE AND SKIN IRRITANT" and "POTENTIAL SENSITIZER" are on the principal display panel of the AQUABAC II XT Biological Larvicide label. A standard drift statement is required to mitigate exposure to residents and bystanders.

Key risk-reduction measures - Environment

The AQUABAC II XT Biological Larvicide label will include the following statements: "ENVIRONMENTAL PRECAUTIONS: May be harmful to beneficial insects. Avoid direct contact with beneficial insects when applying the product in the greenhouse."

"DO NOT allow releases, effluent or runoff from greenhouses containing this product to enter lakes, streams, ponds or other waters."

Next steps

Before making a final registration decision on AQUABAC II XT Biological Larvicide, containing Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144, Health Canada will consider any written comments received from the public that are directly related to this proposed decision, such as comments directed to the science evaluation, in response to PRD2026-07 up to 45 days from the date of publication (by 4 June 2026) of PRD2026-07. Please forward all comments to Pesticides Regulatory Directorate Publications Section, through the Public Engagement Portal (Public Engagement Portal forms – Consultation Comment). 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 Health Canada makes its registration decision, it will publish a Registration Decision on AQUABAC II XT Biological Larvicide, containing Bacillus thuringiensis subsp. israelensis serotype H-14, strain BMP-144 (based on the Science evaluation of PRD2026-07). In addition, the test data referenced in PRD2026-07 will be available for public inspection, upon application, in the Pesticides Regulatory Directorate's Reading Room. For more information or if you have questions, please contact the Pesticides Information Service.