The Health and Safety Executive (HSE) has recently published its conclusion regarding the herbicidal active substance prosulfuron, which is widely used for controlling a range of broadleaf and grass weeds in maize and sweetcorn. Following an extensive risk assessment and public consultation, an important amendment has been made to its approval restrictions.
Applicant and Substance
Syngenta Crop Protection AG submitted the application for this amendment. Prosulfuron, a key herbicide in weed management, has proven effective in various crops, particularly maize and sweetcorn, by controlling both broadleaf and grass weeds.
HSE’s Conclusion
On 30 August 2024, HSE published its conclusion, stating that the restriction on prosulfuron, which previously limited its use to one application every three years on the same field at a maximum dose of 20g active substance per hectare, could be lifted. This decision was based on an updated risk assessment, which had undergone public consultation. The published conclusion can be accessed on the HSE website under the active substance amendments section.
Previous Restrictions and Risk Assessment
The previous restrictions were in place to manage environmental risks, particularly regarding groundwater contamination. However, the updated studies and risk assessments demonstrated that prosulfuron’s environmental impact, under current conditions, does not warrant these limitations. The substance's behaviour in the soil and its degradation were key factors in this decision.
Next Steps
HSE has referred its conclusion to the competent authorities in Great Britain (GB) as part of the Agency Agreements between HSE, Defra, and the devolved governments. The final decision on the approval of prosulfuron without the restriction will be made by these authorities. Users are advised to monitor updates through official channels.
Public and Environmental Health Considerations
While the restriction has been removed, HSE’s risk assessment confirmed that prosulfuron, when applied under the new guidelines, does not pose significant risks to public or environmental health. Detailed studies on the substance’s metabolites in groundwater have ensured that any safety concerns have been thoroughly addressed.
The amendment to prosulfuron’s approval marks a significant change in its regulatory framework in Great Britain. It provides more flexibility for agricultural use while ensuring that environmental and public health standards are upheld. Further details on the conclusion and updated guidelines can be found on the HSE website.
