Cracked exhaust manifold on 1997 Toyota Corolla

Shroud over exhaust manifold is cracked in several places. In addition, I can see several cracks in the manifold through the vents in the shroud. Car is a work car that is a gift; drive it roughly 160 mi per week primarily to work and back (22 mi round trip). What are the concerns to the vehicles operation as well as others in not repairing it?

Asked by for the 1997 Toyota Corolla
You will be breathing in poison. The fumes from an engine, especially as it gets colder can be deadly. Also, you may warp the valves as the cold air hits them when the engine is hot and you shut it off. You may also start a fire in your engine compartment as the EXTREMELY hot exhaust blasts against things that can burn like all the plastic under your hood. Your car will run poorly as it gets cold and you will be using MUCH more fuel as the Oxygen sensor gets hit with outside air. I would fix your car.