Health Canada, pursuant to subsection 28(1) of the Pest Control Products Act, is proposing registration for the sale and use of S-3100 Technical (Rapidicil Technical), S-3100 0.46 EC Herbicide and V-10488 0.94 SE Herbicide, containing the active ingredient epyrifenacil. S-3100 0.46 EC Herbicide is to be applied pre-plant surface to canola, field corn, spring and winter wheat, and pre-plant surface and pre-emergence to soybean. V-10488 0.94 SE Herbicide is to be applied pre-plant surface to spring wheat and pre-emergence to soybean. Both products can also be used in fall burndown and fallow land programs, to maintain bare ground non-cropland, and for industrial vegetation management (IVM).
The co-active ingredient flumioxazin (in V-10488 0.94 SE Herbicide) is currently registered for the control of weeds in numerous crops and container-grown ornamentals. For details, see Evaluation Report ERC2010-05, Flumioxazin, Proposed Registration Decision PRD2013-20, Flumioxazin, and Registration Decision RD2014-11, Flumioxazin.
The co-active ingredient pyroxasulfone (in V-10488 0.94 SE Herbicide) is currently registered for the control of weeds in numerous crops. For details, see Proposed Registration Decision PRD2012-20, Pyroxasulfone, and Registration Decision RD2016-01, Pyroxasulfone.
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.
What is epyrifenacil?
Epyrifenacil is an inhibitor of protoporphyrinogen oxidase (PPO) in the chlorophyll biosynthetic pathway. Inhibiting PPO in plants leads to an accumulation of phototoxic chlorophyll precursors which, in the presence of light, produce activated oxygen species that disrupt cell membrane integrity and cause necrosis of plant tissues, leading to plant death. Epyrifenacil uses a novel binding mechanism and controls weed biotypes that are resistant to other chemical families classified as PPO inhibitor herbicides. Epyrifenacil is rapidly absorbed into foliage, and unlike other PPO inhibitor herbicides, it is translocated in the plant.
What is the value of S-3100 0.46 EC Herbicide and V-10488 0.94 SE Herbicide?
S-3100 0.46 EC Herbicide provides burndown control of both grass and broadleaf weeds in canola, field corn, soybean, and wheat. V-10488 0.94 SE Herbicide provides burndown control of the weeds controlled by S-3100 0.46 EC Herbicide, and residual control of the weeds controlled by flumioxazin and pyroxasulfone in soybean and wheat. Both products can also be used in fall burndown and fallow land programs, to maintain bare ground non-cropland, and for industrial vegetation management (IVM).
S-3100 0.46 EC Herbicide, a formulation of epyrifenacil, is to be applied pre-plant surface to canola, field corn, and spring and winter wheat and pre-plant surface and pre-emergence to soybean. It can also be used in fall burndown and fallow land programs, to maintain bare ground non-cropland, and as well for IVM.
It provides burndown control of both grass and broadleaf weeds at a rate range of 182–363 mL/ha in canola and fall burndown and fallow land programs, 363–726 mL/ha in field corn, soybean, spring and winter wheat, and 726–1452 mL/ha to maintain bare ground non-cropland and for IVM.
V-10488 0.94 SE Herbicide, a co-formulation of epyrifenacil with registered active ingredients flumioxazin and pyroxasulfone, is to be applied pre-plant surface to spring wheat and pre-emergence to soybean. It can also be used in fall burndown and fallow land programs, to maintain bare ground non-cropland, and for IVM. It provides burndown control of the weeds controlled by S-3100 0.46 EC Herbicide and residual control of the weeds controlled by flumioxazin and pyroxasulfone at 1.75–2.0 L/ha in soybean and in fall burndown and fallow land programs, 1.75 L/ha in spring wheat, and 1.75–3.5 L/ha to maintain bare ground non-cropland and for IVM.
S-3100 0.46 EC Herbicide and V-10488 0.94 SE Herbicide provide contact and systemic control of a broad-spectrum of grass and broadleaf weeds, including many that are considered to be the most damaging problematic weeds in conservation crop tillage systems. Although epyrifenacil is classified as a Group 14 mode of action herbicide, it has a unique binding mechanism, which controls weed biotypes that are resistant to other chemical families within the same mode of action group. The application of these herbicides reduces early-season weed competition to the emerging crop, allowing the crop to benefit from additional moisture, nutrients, and light that would otherwise be captured by the weeds. Weed management at this time is critical as the crop does not compete well with weeds until crop canopy closure. Starting with a clean field is one of the most important steps in conservation crop tillage weed control and cover crop management to ensure maximum yield.
Next steps
Before making a final registration decision on epyrifenacil, S-3100 0.46 EC Herbicide and V-10488 0.94 SE Herbicide, 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 PRD2026-13 up to 30 days from the date of publication (by 20 September 2026) of PRD2026-13. Please note that, to comply with Canada’s international trade obligations, consultation on the proposed MRLs will also be conducted internationally via a notification to the World Trade Organization. Please forward all comments to Pesticides 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.
