The site of the chemical spill on Highway 401 at Mallorytown has been contained.
All vehicles have been re-routed and anyone with potential exposure to the leaking chemical has been sent to hospital for medical attention.
The Township of Leeds and the Thousand Islands says there is no risk to the general public. The Ministry of Environment has been notified and clean-up crews are on site.
The OPP says Highway 401 will remain closed indefinitely between the Mallorytown and Lansdowne exits.
A map of detours around the closure can be found below.
