Proposed Registration Decision PRD2022-07, 98Sumithrin, MGK 3145 MUP, and MGK Formula 31451

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The online consultation is now closed.

Pest Management Regulatory Agency
20 May 2022
ISSN: 1925-0886 (PDF version)
Catalogue number: H113-9/2022-7E-PDF (PDF version)

Summary

Table of contents

• Proposed registration decision for 98Sumithrin
• What does Health Canada consider when making a registration decision?
• What is 98Sumithrin?
• Health considerations
• Environmental considerations
• Value considerations
• Measures to minimize risk
• Next steps
• Other information

Proposed registration decision for 98Sumithrin

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 S1-183 Technical Grade, containing the technical grade active ingredient 98Sumithrin, and the manufacturing product MGK 3145 MUP and the end-use product MGK Formula 31451, containing the active ingredients 98Sumithrin and N-octyl bicycloheptene dicarboxide (MGK-264). MGK Formula 31451 is a pressurized spray that is applied indoors as a crack-and-crevice and spot treatment, and to furniture, including mattresses, to control bed bugs and bed bug eggs.

The co-active ingredient, MGK-264, is an insecticide synergist that is always co-formulated with one or more active ingredients belonging to the synthetic pyrethroids and pyrethrins group. It enhances the pesticide properties of other insecticides and is registered for a wide spectrum of insect pests in or on stored food and feed, structures, companion animals, human habitat and recreational areas, human skin, clothing and proximal sites, and outdoor residential areas. For details see the Re-evaluation Decision RVD2019-10, N-Octyl Bicycloheptene Dicarboximide (MGK-264) And Its Associated End-use Products and the Proposed Re-evaluation Decision PRVD2017-15, N-Octyl Bicycloheptene Dicarboximide (MGK-264) And Its Associated End-use Products.

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 PRD2022-07, 98Sumithrin, MGK 3145 MUP, and MGK Formula 31451 provides detailed technical information on the human health, environmental and value assessments of 98Sumithrin, MGK 3145 MUP and MGK Formula 31451.

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 98Sumithrin, MGK 3145 MUP and MGK Formula 31451, 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 98Sumithrin, MGK 3145 MUP and MGK Formula 31451, 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 PRD2022-07.

What is 98Sumithrin?

98Sumithrin is a pyrethroid insecticide used to kill bed bugs and bed bug eggs. It is combined with the synergist N-octyl bicycloheptene dicarboximide in the commercial-class product, MGK Formula 31451. 98Sumithrin affects the insect nervous system causing paralysis and death. 98Sumithrin is used to control bed bugs and bed bug eggs indoors including on mattresses and upholstered furniture.

Health considerations

Can approved uses of 98Sumithrin affect human health?

MGK 3145 MUP and MGK Formula 31451, containing 98Sumithrin and co-formulated with N-octyl bicycloheptene dicarboxide, are unlikely to affect your health when used according to proposed label directions.

Potential exposure to 98Sumithrin may occur when handling and applying the end-use product or when coming into contact with treated surfaces. When assessing health risks, two key factors are considered:

• the levels at which 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 dose levels more than 100-fold 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 98Sumithrin was of low acute toxicity by the oral, dermal, and inhalation routes of exposure. 98Sumithrin was non-irritating to the eyes and skin, and did not cause an allergic skin reaction.

The manufacturing concentrate MGK 3145 MUP was of low acute toxicity by the oral, dermal, and inhalation routes of exposure. MGK 3145 MUP was minimally irritating to the eyes; however, it was moderately irritating to the skin and caused an allergic skin reaction. Consequently, the signal word “WARNING” and the hazard statements “SKIN IRRITANT” and “POTENTIAL SKIN SENSITIZER” are required on the label.

The end-use product MGK Formula 31451 was considered to be of low acute toxicity by the oral, dermal, and inhalation routes of exposure. It was minimally irritating to the eyes but was considered mildly irritating to the skin; consequently, the signal word and hazard statement “CAUTION – SKIN IRRITANT” are required on the label. MGK Formula 31451 is not considered to 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 98Sumithrin 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 the liver, pituitary, adrenals, epididymides, and nasal cavity.

There was an indication that the young were more sensitive than the adult animal. 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 water and food

As MGK Formula 31451 is proposed to be applied indoors as a crack-and-crevice and spot treatment, and to furniture, including mattresses, to control bed bugs and bed bug eggs, dietary exposure to residues of 98Sumithrin in water and food is not expected.

Health risks to workers

Occupational risks are not of health concern when MGK Formula 31451is used according to the proposed label directions, which include protective measures.

Workers applying MGK Formula 31451 and entering recently treated sites can come in direct contact with 98Sumithrin residues. Therefore, the label specifies that anyone applying MGK Formula 31451 must wear a long-sleeved shirt, long pants, chemical-resistant gloves, socks and shoes. In addition, taking into consideration the label statements and the duration of exposure for handlers and postapplication workers, the risks to these individuals are not of health concern.

Health risks in residential and other non-occupational environments

Risks in residential and other non-occupational environments are not of health concern when MGK Formula 31451is used according to the proposed label directions and restrictions are observed.

Adults, youth and children may be exposed to 98Sumithrin by dermal contact, while performing activities in residential areas treated by commercial applicators. Children may also be exposed to 98Sumithrin when playing on treated surfaces, and subsequently ingesting the product as a result of hand- or object-to-mouth transfer. No risks of concern were identified.

Health risks to bystanders

Bystander risks are not of health concern when MGK Formula 31451 is used according to the proposed label directions and restrictions are observed.

With the restrictions on the label, that prohibit people (other than the applicator) and animals from being in treatment areas during application, bystander exposure is expected to be minimal. Therefore, health risks to bystanders are not of concern.

Environmental considerations

As MGK Formula 31451 is proposed to be applied indoors as a crack-and-crevice and spot treatment, and to furniture, including mattresses, to control bed bugs and bed bug eggs, an environmental assessment was not required.

Value considerations

What is the value of MGK Formula 31451?

MGK Formula 31451 has value in killing bed bugs and bed bug eggs when applied as a crack-and-crevice and spot treatment indoors, including to sites such as mattresses and upholstered furniture.

Bed bugs are a pest of public health concern that feed on the blood of humans and animals and can have substantial impacts on the well-being of Canadians. Bed bugs are difficult to control, and resistance to many registered control products is present in bed bug populations across Canada. MGK Formula 31451 will provide a new tool for use against bed bugs and bed bug eggs.

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 S1-183 Technical Grade, MGK 3145 MUP and MGK Formula 31451 to address the potential risks identified in this assessment are as follows.

Key risk-reduction measures

Human health

To reduce the potential of workers coming into direct contact with 98Sumithrin dermallyor through inhalation, workers applying MGK Formula 31451and performing cleaning and repair activities must wear a long-sleeved shirt, long pants, chemical-resistant gloves, socks and shoes. Risks to workers are not of health concern when MGK Formula 31451 is used according to the proposed label directions. Standard label statements are on the label to provide directions for proper ventilation prior to entering treated sites, and to minimize postapplication exposure to residents and domestic animals. Furthermore, label statements prohibiting people and animals from being in treatment areas during application are present on the label.

Next steps

Before making a final registration decision on 98Sumithrin, MGK 3145 MUP and MGK Formula 31451, Health Canada’s PMRA will consider any comments received from the public in response to PRD2022-07. Health Canada will accept written comments on PRD2022-07 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 Health Canada makes its registration decision, it will publish a Registration Decision on 98Sumithrin, MGK 3145 MUP and MGK Formula 31451 (based on the Science Evaluation of PRD2022-07). 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.