Yes
if it is the exhaust manifold ,yes. if your breathing in those exhaust fumes you can get carbon monoxide poisoning
Sterno fumes can certainly cause eye irritation. The fumes can also cause irritation in the lungs after significant exposure.
No. The exhaust manifold only carries burned exhaust fumes from the engine to the rear of the vehicle. It has nothing to do with the oil or fuel system. It also cannot prevent the engine from starting. However a clogged catalytic converter can cause the engine not to start. Fuel in the oil is caused by a leaking injector on a FI engine or a bad needle valve and seat of an carburetor engine.
Oil fumes in the crankcase are common. Excessive oil fumes can be an indication of a broken or worn piston ring.
Diffusion occurs naturally, and technically they are not fumes. Fumes are the condensates of metals. Ammonia vapors are what you smell.
Air pressure difference between the heat at the manifold and the relative cold outside. The manifold can get very hot, which increases pressure towards to outer, cooler, opening. Also, the pressure of more exhaust gas being pump into the manifold from continued combustion from the engine.
A manifold leak is usually in reference to a failure of the intake manifold gasket. It can leak air, oil or coolant. It can leak to the outside of the engine or internally into the engine. A manifold leak may also refer to the Exhaust manifold that is leaking exhaust fumes from a bad gasket or a crack in the manifold.
Car fumes are not very good for the environment and can cause global warming.
Death!
Moth ball fumes do not cause memory loss, but they have been reported to cause dazedness, erratic behavior, and other odd symptoms.
Paint fumes (depending on what kind) can cause damage to any human. Its often a good idea to refrain from breathing in paint fumes whether or not you have an aortic valve replacement. Paint fumes when inhaled can cause damage to and kill brain cells (which you have a limited supply of).
If the car is filling with exhaust fumes, that is a health hazard, and is almost certainly caused by a broken or leaky exhaust pipe.