Metrolinx is calling a near-miss incident that occurred in Toronto last week "extremely concerning" after a GO train and a truck laden with chemicals almost collided at a rail crossing.

The transit agency announced on Monday that it had implemented new safety measures on the Lakeshore East Line following the near-miss at the Manse Road rail crossing in Scarborough.

According to Metrolinx, a truck transporting chemicals to the Dow Chemical Company facility on Manse Road nearly collided with a GO train at a level rail crossing just outside of the chemical plant.

The crossing is located roughly 75 metres from the closest residence.

The incident triggered a full-scale safety assessment, and the transit operator has made swift changes to prevent such incidents from occurring in the future.

As a result of this incident, riders on the Lakeshore East Line will notice slower speeds when crossing this stretch of track. Metrolinx has limited train speeds to no more than 50 miles per hour when entering the crossing in both directions.

In addition to reduced speeds, a previously scrapped requirement for train whistles has been reinstated at this crossing. The use of train whistles at this crossing was halted after locals complained about constant noise, though it looks like locals will once again be dealing with this frequent disturbance.

This move to reinstate this loud safety measure is in accordance with Transport Canada requirements for the implementation of whistles in any situation where unsafe conditions affect the rail corridor.

Along with these new measures at the crossing, Metrolinx has vowed to continue working alongside Dow Chemical to "ensure the safety of passengers, train crews and the public."

Manse Road is one of just a handful of remaining level rail crossings in Toronto. Most have been phased out for safer grade-separated crossings over the years, though many remain in areas with less traffic, like the sparsely built-out area where Manse Road crosses the rail tracks.